In this study, the role of sac section area and parent vessel diameter on the hemodynamic feature of the blood flow in selected internal carotid artery (ICA) aneurysms is comprehensively investigated. The changes of wall shear stress, pressure, and oscillatory shear index (OSI) of blood stream on the vessel for various aneurysms with coiling treatment. To attain hemodynamic factors, computational technique is used for the modeling of non-Newtonian transient blood flow inside the three different ICA aneurysms. Three different saccular models with various Parent vessel mean Diameter is investigated in this study. The achieved outcomes show that increasing the diameter of the parent vessel directly decreases the OSI value on the sac surface. In addition, the mean wall shear stress decreases with the increase of the parent vessel diameter. These aneurysms pose a significant risk of rupture, leading to potentially life-threatening hemorrhages. The rupture of an intracranial aneurysm remains a critical challenge in neurosurgery, and understanding the underlying hemodynamic factors contributing to aneurysm rupture is crucial for developing effective treatment strategies5. There are several papers related to biomedical study via theoretical techniques11. The focused on different aspects of biomedical science17.Hemodynamics, which refers to the study of blood flow patterns and forces within blood vessels, plays a vital role in the initiation, growth, and rupture of intracranial aneurysms. Various hemodynamic factors, such as wall shear stress, flow velocity, and pressure distribution, influence the structural integrity of an aneurysm. For instance, elevated wall shear stress and flow impingement on the aneurysm wall can lead to progressive weakening and eventual rupture20. Coiling involves the placement of a small metal coil into the aneurysm sac to promote thrombosis and reduce blood flow into the aneurysm. However, the precise hemodynamic alterations induced by coiling and their impact on the risk of aneurysm rupture are not yet fully understood. There are various treatments for the problem related to human’s health27To mitigate the risk of rupture, endovascular techniques, such as coiling, have emerged as an effective treatment option30.Computational fluid dynamics (CFD) has emerged as a valuable tool for investigating the hemodynamics of intracranial aneurysms and evaluating the effectiveness of treatment strategies. By simulating blood flow within patient-specific vascular geometries, CFD allows researchers to quantify key hemodynamic parameters and analyze their relationship with aneurysm rupture risk. This approach provides valuable insights into the complex flow patterns, wall shear stress distribution, and pressure gradients within the aneurysm31.The findings of this study have the potential to enhance our knowledge of the hemodynamic mechanisms underlying aneurysm rupture and the efficacy of coiling as a treatment strategy. Ultimately, this research may contribute to the development of improved clinical decision-making tools and personalized treatment approaches for patients with ICA aneurysms, with the goal of minimizing the risk of rupture and optimizing patient outcomes33. These parameters provide insights into the flow patterns and forces acting on the aneurysm wall, which can play a crucial role in aneurysm initiation, growth, and rupture. Some of the key hemodynamic parameters will be explained. Wall Shear Stress (WSS) is the tangential force exerted by flowing blood on the vessel wall. Elevated WSS has been associated with increased aneurysm rupture risk. High WSS can lead to endothelial dysfunction, inflammation, and remodeling of the vessel wall, potentially weakening it over time. Flow velocity refers to the speed at which blood flows through the aneurysm and adjacent vessels. Disturbed flow patterns, characterized by high-velocity jets, vortices, and flow impingement on the aneurysm wall, have been linked to an increased risk of aneurysm rupture. Pressure distribution within the aneurysm sac and surrounding vessels can influence the mechanical stress on the aneurysm wall. High-pressure gradients and localized pressure peaks within the aneurysm may contribute to wall degeneration and rupture35.Several key hemodynamic parameters are commonly studied in relation to aneurysm rupture risk36. Higher energy loss has been associated with increased rupture risk, as it indicates inefficient flow patterns and flow disturbances that can weaken the aneurysm wall. Oscillatory Shear Index (OSI) measures the degree of oscillatory flow and changes in the direction of shear stress. High OSI values have been correlated with aneurysm initiation and progression, suggesting a potential role in rupture risk assessment. By studying these and other hemodynamic parameters, researchers can gain valuable insights into the complex interplay between blood flow dynamics and aneurysm rupture. Computational fluid dynamics (CFD) simulations and advanced imaging techniques play a crucial role in quantifying these parameters and investigating their relationship with aneurysm behavior, providing a foundation for improved risk prediction and treatment strategies.The complex flow patterns within the aneurysm, such as recirculation zones and flow impingement, are of interest in understanding the hemodynamics of aneurysms. Disturbed flow patterns can result in regions of low wall shear stress or high pressure, which may promote aneurysm growth and rupture. Energy loss quantifies the dissipation of kinetic energy within the aneurysmIn this study, we aim to explore the role of hemodynamic factors on the risk of rupture in ICA aneurysms and investigate how the coiling technique influences these factors using a computational fluid dynamics approach. By integrating patient-specific vascular geometries, physiological flow conditions, and accurate modeling of coiling procedures, we can gain a deeper understanding of the hemodynamic modifications induced by coiling and their implications for aneurysm rupture risk reduction.Although several investigations have analyzed the aneurysm feature on the risk of bleeding, limited research has presented valuable information on the role of parent vessel mean diameter on the hemodynamic characteristics of blood flow inside the ICA aneurysms. This work tries to investigate the role of Parent vessel mean diameter on the hemodynamic factors related to the bleeding of the saccular ICA aneurysms. Computational fluid dynamic is used to visualize the blood stream inside real three-dimensional ICA aneurysms. Wall shear stress and OSI value in various stages of the cardiac cycle.37 and their geometrical features are compared based on the sac section area and parent mean diameter. It is confirming that all methods were carried out in accordance with relevant guidelines and regulations. Besides, all experimental protocols were approved by of the Ca’ Granda Niguarda Hospital and it is confirmed that informed consent was obtained from all subjects and/or their legal guardian(s).For the selection of the ICA aneurysms, more than 100 aneurysms with different geometrical sizes are obtained from AneuriskAmong these cases, three cases are chosen Fig. , and det40. One-way FSI approach is considered for the interaction of the vessel and aneurysm wall with blood flow41. Due to non-Newtonian blood characteristics, the Casson model is conventionally applied to calculate the viscosity of the blood within the vessel42. The flow is assumed laminar since the velocity of the blood is not high. ANSYS-FLUENT is used for the modeling of the blood flow within saccular aneurysms43. This software used for different engineering applications49The study of the blood stream moves inside the parent vessel and saccular aneurysm requires specific considerations. Transient Navier Stokes equations are used for the modeling of the blood flow inside the aneurysmsSince the blood flow inside the aneurysms and parent vessel is transient, mass flow rate and pressure outlet are applied at the inlet and outlet, respectively. Figure The hemodynamic results of the simulation of the blood inside the selected aneurysm are presented in Table 2. Considerable reduction in this change may related to the high increase of incoming blood flow by increasing of sac section area. In Fig. Figure The variation of the mean sac wall pressure of the selected aneurysm in a diverse range of parent vessel means diameter at peak systolic stage is demonstrated in Fig. The variation of the mean oscillatory shear index (OSI) at early diastolic for various parent vessel mean diameters is demonstrated in Fig. Figure The present study investigates the influence of sac section area and parent vessel diameter on the hemodynamic feature of the blood flow in selected aneurysms. Computational fluid dynamic is applied for the modeling of the transient blood stream in the cardiac cycle. The selected aneurysms are treated and filled by the porous media. The variation of the mean OSI shows that increasing the diameter of the parent vessel directly decreases the OSI value on the sac surface. In addition, the mean WSS decreases with the increase of the parent vessel diameter.


Adolescence phase has high intrinsic and instrumental relevance. The Transformative Action for Rural Adolescents intervention delivered PACE++ curriculum with innovations to introduce a) health and nutrition sessions and b) delivery of the content in community settings of rural Bihar. This paper examines impact of the intervention showcasing establishment of intergenerational community connect for empowering and invigorating adolescent girls on gender attitude, empowerment and adolescent health and nutrition. The impact evaluation is based on a two-arm (intervention and comparison groups) cluster randomized controlled design with two rounds of representative cross-sectional surveys. The baseline and endline sample comprised of 2327 and 2033 adolescent girls (15–19 years), respectively. Descriptive statistical, difference-in-differences and propensity score matching methods are used to confirm the program impact. The DID and PSM analyses confirm high significance of impact on gender equity norms, diets and nutritional knowledge and understanding of employee related rights and responsibilities. School-going adolescent girls performed better than those who have discontinued formal education. The intervention showcases the importance of delivering the modified PACE curriculum in rural settings through leveraging community platforms. The findings call for greater policy attention on scaling up of similar initiatives for empowerment and social capital development of adolescent girls. Unequal opportunities and constricting sociocultural norms are inimical to gender equity and development. Curbs and controls at household and community level often disallow women to pursuit their goals for a healthy and dignified living , 2. ThesBoosting investments in social sector  and physical infrastructure such as roads, information technology, water and sanitation etc. are important for increasing female participation in economic activities , 6. ThesIn view of such intricacies, various national and international organizations are piloting alternative strategies to promote gender equity and empowerment across socio-economically diverse and resource-poor settings . Some ofNotable is the case of the Personal Advancement & Career Enhancement (P.A.C.E.) curriculum designed by Gap Inc. in 2007 –a widely referred PYD model across settings . P.A.C.EThe PACE curriculum, however, offers considerable scope for adaptations to meet the wide range of skill development requirements for youth and adolescents in developing countries . ProjectThe intervention was piloted during 2019–21. As part of the initiative, adolescent girls were mobilized in small groups and were trained on various life skills in domains related to women empowerment, employability skills, and adolescent health and nutrition. The pilot focused on strengthening self-reliance of vulnerable adolescent girls so as to enable them to enter the workforce with strong life skills. Against this background, this paper specifically evaluates the impact of the TARA initiative on improving indicators related to self-efficacy and empowerment of adolescent girls for realizing their goals and aspirations. The analyses are based on data from a two-arm cluster randomized controlled design. Before proceeding with the analysis, a brief note on the TARA initiative is in order.Hindi with minor modification of games and methodologies to suit project implementation in Bihar. The core capacities of PCI in domains of family planning, women’s health and nutrition were instrumental in this process. Also, the modules were adapted for a community-based outreach format. It is worth noting that the PACE curriculum is essentially designed for schools whereas the TARA project aimed at engagement with adolescent girls in community settings. The PACE curriculum in India was previously administered in school settings but absenteeism and time-constraints in school-based engagement required a community centric approach for delivery of PACE model for wider outreach among adolescents. Accordingly, the 16 sessions under the PACE modules  were tailored and contextualized for the target group. The pilot also relied on field visits and interactions to ease the curriculum adoption participatory process for involving adolescent girls. This helped in improving the language and comprehension necessary for elaborating the concepts used in the tools and also aided in conducting effective training sessions with adolescent groups.Transformative Action for Rural Adolescents (TARA) pilot is an 18-month intervention launched in November 2019 in Rohtas district of Bihar with funding support from Bill and Melinda Gates Foundation (BMGF) and GAP Inc. PCI in coordination with ICRW and Gap Inc. customized the PACE curriculum for the intervention to be consistent with local context and needs of the focus group. The initial contextualizing of PACE++ curriculum and training material on life skills including gender and empowerment, self-efficacy, employability, entrepreneurship, and health and nutrition was done by PCI. The process entailed redesigning of the modules in a simple and easy way to understand The TARA pilot was implemented in two selected blocks of Rohtas district in Bihar. The pilot mobilized a total of 1205 adolescent girls  and trained them on various aspects such as empowerment, employability, adolescent health and nutrition. The average attendance of adolescents in the PACE++ sessions was 86%. Prior to community roll-out, the training facilitators and supervisors also went through an induction training for improving their understanding about the project and also their ability to deliver the PACE++ curriculum. The training involved both classroom teaching (theory and practice) as well as field-based learning for comprehending session delivery in community settings. The introductory module relied on description of the core concept and encouraged discussion on the subject through use of videos on stories and stereotypes. This served as ice-breaking sessions to allow greater interaction between the adolescent girls and the community facilitators. For mobilization purposes, the PCI team made household visits for rapport building and information sharing about the TARA program. Each module was delivered only after trainings of the community facilitators which included theory sessions, group practice sessions and also field based piloting and learning for appropriate delivery of the sessions. The sessions were primarily conducted during the weekends at convenient timings to facilitate greater participation. Overall, the intervention aimed at 100 hours of direct and indirect contact with the adolescents through module sessions, club activities including sharing of information and materials on the various modules. The monitoring of the intervention was done by the project team at the district and the block level with a quality assurance checklist developed to review the conduct of the session. Feedback to community facilitators was also provided based on the monitoring to enhance efficiency of the facilitators and consequently improve training outcomes.Sakhi Saheli (friends) forums to boost participation. This was further instrumental as adolescent girls were encouraged to join the TARA club that sought greater linkages with the SHG groups under JEEViKA initiative of the state government. The TARA program also did a mapping of the skill learning preferences of adolescents and all adults were accordingly linked to Rural Self-Employment Training Institute (RSETI) of the Government of India as well as other skill development centers.The village-level organizations (VO) and self-help group (SHG) forums  in Bihar) were also involved in this initiative. Given the vast network of SRLM, there was a high probability of engaging adolescents through active engagement with the SRLM network. In particular, the JEEViKA staff and cadres were oriented along with village organizations referred to as the Social Action Committee (SAC) regarding the rationale and objectives of the TARA project. The self-help group members as part of the JEEViKA were sensitized for gender equity and women empowerment concerns to motivate greater participation of adolescents from their household and neighborhood. The out-of-school adolescents were also approached through Nonetheless, it is worth mentioning that the TARA pilot was not devoid of the disruptions caused due to the COVID-19 pandemic. This affected the planned activities and necessitated some re-designing of the project strategy to connect with the adolescent groups. In particular, the size of the adolescent groups was reduced from 20–25 members to 10–15 members per group. This implied requirements of additional time and human resources to ensure delivery of the adapted PACE curriculum. Also, there was continuous effort to provide support and motivation, through online channels, to enable the adolescent groups to face the challenges posed by the pandemic. PCI initiated several activities  for de-stressing and prevention from COVID-19.th day of October), international women’s day (8th day of March) and cluster-level events such as “betiyon ki awaz” (translated as voice of the daughters). However, in April 2021 the second wave of COVID-19 further affected the program activities. During this period, PCI initiated responsive support to the girls on COVID-19 through alternative mediums and provided appropriate information to the girls on ‘COVID appropriate behavior’ and also motivated them to be messengers for COVID-19 vaccination.With some improvements in COVID-19 situation and lockdown relaxation, the TARA pilot field activities were re-started in October 2020. During the post-COVID period, participation and leadership abilities among adolescent girls was encouraged through celebration of international girl child day  cluster randomized controlled design was used based on two rounds of representative quantitative cross-sectional surveys with adolescent girls (15–19 years). The baseline survey was conducted during November 2020 to January 2021 whereas the end of the project survey was carried out during January 2022. The sample size for the evaluation is derived based on the assumption of observing a 10-percentage point change in critical indicators between intervention and comparison arms after the intervention with 80% power and 95% confidence of interval. The basic sample size for each arm is calculated to be 385 which further adjusted for the cluster design approach. In particular, 24 clusters per arm is required based on the assumption of a between-cluster variation of 0.25 along with the intent to interview 48 respondents per cluster. Accordingly, a total sample of 2304 adolescent girls (1152 each in intervention and comparison group) for the baseline and endline survey is finalized.All the inhabited villages (128) under the two selected blocks of the district are included for randomization. However, villages with less than 100 households or with high school are removed before randomization for ensuring adequacy of eligible sample. A total of 12 villages from each Block are randomly assigned to the two arms (intervention and comparison). The sampling frame for adolescent girls was developed based on mapping and listing operations for identifying eligible in the selected villages. The exercise is repeated for endline survey. Further, from each village a sample of 48 adolescent girls is randomly selected for both baseline and endline surveys. The baseline sample comprised of 2327 adolescent girls  and endline sample of 2033 adolescent girls . However, within the intervention area, 618 adolescent girls reported regular participation in TARA project activities and they constitute the final analytical sample for the intervention group.The survey was conducted by a team of trained field investigators  using structured interview schedules that was pre-tested in a different district of the state. The inclusion criteria is as follows: unmarried adolescent girls (15–19 years) who are usual residents of the village and are willing to participate in the survey. Parental consent  was also sought before approaching the adolescent girls for the interview. The interview schedule collected information on socioeconomic background of the respondents along with information on the core domains related to empowerment, employment, gender equity and health and nutrition. However, the data does not include any information which could reveal the identity of the participant.Core to the TARA’s programmatic approach is an evidence-based, gender-integrated life skills training and mentoring program, called Personal Advancement & Career Enhancement (P.A.C.E.) that addresses five core domains. The impact across these five domains of empowerment, employment and adolescent health and nutrition is assessed through the following measures: a) gender equity attitudes, b) diet and nutrition, c) self-esteem, d) self-efficacy and e) employee roles and responsibilities. The items used for each domain measures are available in S1 Table in pucca house build from durable materials or not), cooking fuel (clean fuel or not), family income (BPL/APL–below poverty line or above poverty line as per state government food ration cards) occupation , maternal education , paternal education , currently in school (yes or no).Participation of the adolescent girls in the community activities under the TARA intervention is the main explanatory variable  and its impact on the five outcome measures. First, we create binary variable categories for the domain scores (top two quintile scores vs bottom three quintile scores) and apply logistic regression model to understand the association of program exposure with the likelihood of being in upper quintiles of domain scores. Second, as the five domain scales also resemble the properties of count data, we apply Poisson regression model to understand the change in expected scores that can be associated with program participation. Finally, two prominent econometric approaches for impact evaluation–viz. difference-in-differences (DID) and propensity score matching (PSM)—are applied for confirming the impact of program exposure on the selected domains. The DID method compares the outcome measures of intervention and comparison group across baseline and endline period [Descriptive statistics is provided for the outcome measures and the key explanatory variables . Cronbacspective , 30. Cohe period . The DIDe period . The proThe background characteristics of the intervention and comparison group across baseline and endline period is similar . Over 80The mean domain specific scores for the comparison and intervention group have increased between the baseline and endline period . The aveFurther, the average knowledge score regarding employee rights and responsibilities (maximum score 13) is low but show increments for the adolescents in the intervention group . Small increments in scores are apparent in self-esteem and self-efficacy scores. The average score for the former increased from 25.7 in baseline to 27.6 during endline whereas for the latter it increased from 27.5 in baseline to 29.3 in endline.d value to provide insights on the effect size. This statistic describes the magnitude of the program impact for the intervention group and—as a general rule of thumb–effect size greater than 0.2 is considered to be of policy interest. The higher values can be further categorized to be of small (0.2 to 0.5), medium (0.5 to 0.8) or large (0.8 and above) impact. The program impact based on Cohen’s d is inferred to be of medium size for two domains of gender equitable roles  and diet and nutrition  and small size for three domains of self-esteem , self-efficacy  and employee rights / responsibilities .Logistic regression analysis is applied to examine the likelihood of better performance among the program participants . PCA basThe bottom panel of The results for the socioeconomic correlates from the adjusted logistic and Poisson regression are reported in S4, S5 Tables in The DID analysis confirms a significant impact of the program on the exposed participants . The unaThis study evaluates the impact of delivering PACE++ curriculum for adolescent girls in community settings of rural Bihar. Based on the quasi-experimental study design, the study focused on domains related to gender attitudes, empowerment and dietary practices. The five salient findings of the study are as follows. First, TARA intervention had a positive impact on domain scores of intervention group comprising of adolescent girls who participated in all or most of program meetings and events. Second, the DID and PSM analyses confirm that the impact are specifically significant for the domains of attitudes toward gender equity norms, nutritional knowledge and understanding of employee related rights and responsibilities. Third, the effect size–as discerned through Cohen’s d–is of policy interest as all the domain scores show small to medium size program impact on the intervention group. Fourth, the intervention group demonstrated a positive change in dietary diversity practices whereby consumption from five or more food groups increased significantly over the intervention period. Fourth, maternal education and household wealth status have an independent influence on domain scores. In particular, maternal education is found to have significant association with empowerment related scales of self-esteem and self-efficacy. Household wealth status has a positive bearing on expected score of dietary practices. Finally, the expected domain scores of school-going adolescent girls is higher than those who have discontinued formal education.The study, however, is not devoid of limitations. First, during endline about two-third of the intervention area sample reported greater exposure to the program and was treated as the intervention group. This exposure-based attrition of sample may bias significance of program impact across domain scores. The adopted sampling approach, however, was necessary to check for overall program participation and to ensure that the sample was drawn randomly from the community and was not necessarily restricted to the program participants to discern broader implications of the program. Nevertheless, the analysis focused only on regular participants to estimate the magnitude of the impact. Second, the construction of the domain scores relied on established scales for the domains related to gender equity  and empowerment . The scale for diet and nutrition apply well-established dietary diversity indicators and knowledge of most widely prevalence micronutrient deficiency (anemia). Whereas in the absence of relevant scale for employment related indicators, the items reflecting employee rights and responsibilities was utilized that provide a balance between awareness of employee duties and being informed regarding basic rights to safeguard employees from exploitation. This also suggests a need for developing valid and reliable scale for adolescents to assess the effect of like-skills training on employability in developing country contexts . Third, Life skills–particularly soft skills related to self-efficacy, communication and leadership—are inextricably linked to equity and empowerment whose relevance increases manifold for women and girls across the developing world , 35. HowThe TARA intervention aimed at leveraging the PACE curriculum and delivering it in a rural community setting that has wide policy relevance in the Indian context. Given the large scale of the informal sector, there might be limited work platforms to provide such training modules for adolescent girls. The SHG platforms that are supported by the government provide an important avenue to empower adolescent girls, develop their resilience and support their aims and aspirations . In partThe program impact size of the intervention is of policy interest as it demonstrates possibility of improving adolescent well-being through outreach based on community platforms. The effect size as discerned by Cohen’s d is encouraging enough to be considered for wider scale up of such initiatives using existing platforms such as JEEViKA and other self-help group and adolescent forums. The effect size is also comparable to similar to other adolescent girl programmes delivered through school-based initiatives . The booThe program impact of TARA intervention is driven by a sound theory of change rooted in the positive youth development framework , 14, 15.It is worth noting that the impact of the intervention on domain scores pertaining to self-esteem and self-efficacy is relatively small. This finding is partly associated with higher baseline scores on these indicators whereas greater improvements in self-esteem are noted especially when the initial scores are lower . Such paBefore concluding, it is also important to outline the lessons learnt from program intervention during the pandemic period. The direct engagement with TARA groups immediately alerted the wide sense of fear and anxiety among adolescents that manifested in psychosocial and mental health concerns. The impact could be disproportionately on adolescent girls from economically unprivileged background. The COVID-19 protocols also implied that all efforts were counselling and information sharing were to be through digital mediums and its efficacy can be a challenge for those lacking access to mobile devices and internet. This also curtailed the program effect as the results demonstrate greater benefits for those who were regular participants. Such impact, however, was unavoidable and similar concerns are widespread across other remote and rural settings of India that have weak IT infrastructure as well as poor means for digital communication . This alThe TARA intervention contributed to the development of the strategies for engaging and empowering adolescent girls through augmenting health and nutrition issues in the widely used PACE curriculum and also implementing this in community-based settings. Both the changes are extremely important as adolescent well-being cannot be discussed in isolation with health and nutrition concerns and also that reaching out to these in rural settings warrants a community centric platform as school settings may have both time and participation constraints. It is encouraging that the intervention shows a discernible impact of PACE++ curriculum training on a range of indicators associated with women empowerment and adolescent health and nutrition. The intervention also highlights the feasibility of delivering the modified PACE curriculum in rural settings and the scope for leveraging community platforms such as SHGs for program roll out. This provides further opportunities to scale up these through government initiatives such as SRLM and JEEViKA. The findings overall are encouraging but they also reveal new challenges such as dietary practices among adolescent girls that has huge implications on population health and well-being. Notwithstanding program impact and effect size, greater caution is warranted while scaling up of such models. In particular, appropriate contextualization of the session tools and implementation techniques has an instrumental role to play. Before concluding, it is worth reiterating the adverse effects that adversities such as pandemics can have on adolescent lives. During such testing times the social capital of adolescent group forums and platforms can be of high relevance and support. To conclude, the TARA intervention showcases the importance of delivering the modified PACE++ curriculum in rural settings through leveraging community platforms. The linkages of the program with established government institutions and initiatives boost the sustainability prospects of the initiative. The pilot, therefore, provides robust evidence for upscaling, replicating and promoting similar programs to reach out to all adolescent girls in India and elsewhere.S1 Checklist(DOC)Click here for additional data file.S1 Data(ZIP)Click here for additional data file.S1 File(DOCX)Click here for additional data file.


These results are discussed inrelation to the trans–cis photoisomerization of xanthophylls observed in the human retina.It can be concluded that photoisomerization of xanthophylls is a regulatorymechanism that is important for both the modulation of light filtrationthrough the macula and photoprotection by quenching singlet oxygenand creating a barrier to oxygen permeation to membranes.Here, we address the problem of the antioxidant activityof carotenoidsin biomembranes. The activity of lutein and zeaxanthin in the quenchingof singlet oxygen generated by photosensitization was monitored inlipid vesicles using a singlet oxygen-sensitive fluorescent probeand with the application of fluorescence lifetime imaging microscopy.The antioxidant activity of xanthophylls was interpreted on the basisof electron paramagnetic resonance oximetry results showing that xanthophyllsconstitute a barrier to the penetration of molecular oxygen into lipidmembranes: to a greater extent in the 13- Singlet oxygen was generated via photosensitizationin the surrounding water phase and in the lipid membrane and monitoredby a specific, singlet-oxygen-sensitive fluorescence probe presentin the lipid vesicles.9 The use of fluorescencelifetime imaging microscopy (FLIM) enabled the imaging and analysisof the generation and diffusion of singlet oxygen in a single lipidvesicle. These studies were combined with nanooxymetry based on electronparamagnetic resonance (EPR) spectroscopy, which created the opportunityto gain a unique and precise insight into the antioxidant propertiesof xanthophylls in the environment of lipid membranes.Lutein and zeaxanthin belongto a group of polar carotenoid pigments  presentin both the animal and plant kingdoms and play diverse biologicalfunctions, including protection against oxidative damage.10 orwith additional illumination with a 630 nm laser that emits red lightabsorbed by the toluidine blue (TB) dye, an efficient singlet-oxygen-generatingphotosensitizer.9 Fluorescence emissionwas analyzed separately in two channels: one selective for SOS andthe other selective for TB (see our previous study for a detailedspectroscopic characterization of the system9). As seen from the comparison of the fluorescence intensity of theSOS probe, singlet oxygen is efficiently generated in a system containingTB photosensitizer molecules excited with red light to a much greaterextent than in the case of excitation with a blue light laser preferentiallyabsorbed by the SOS probe. The fluorescence intensity on the images,recorded in both the TB and SOS channels, shows that singlet oxygenis generated efficiently and concentrated predominantly in the lipidmembranes and, to a lesser degree, present also in the water phaseinside and outside vesicles (see sn-glycero-3-phosphocholine (POPC) or POPC containing all-trans zeaxanthin as an additional lipid membrane component. As seen, thepresence of xanthophyll in the membranes significantly reduces thepresence of singlet oxygen in the entire system. cis xanthophylls were found to be significantlymore effective in antioxidant activity compared to the all-trans molecular configuration. To understand such an effect,we used a nanoscale oximetry approach based on the EPR spin labeltechnique.cles see 1. The ra13 It should be noted here that the onset of OTP is not related toactive transport across or within the lipid membrane but is a usefulmonitor of membrane fluidity that reports on the translational diffusionof small molecules, such as oxygen. trans or 13-cis. As seen, boththe all-trans xanthophylls effectively decrease theOTP within the hydrophobic core of the lipid bilayer, in accordancewith the original observation of Subczynski et al. for dimyristoylphosphatidycholine(DMPC) and egg yolk phosphatidycholine (EYPC) membranes containing10 mol % carotenoids.14 Importantly, asrevealed in the present study, this effect is pronounced at a relativelylow concentration of 1 mol % xanthophyll with respect to lipids (POPC).It is very likely that an overall effect of xanthophylls on the localdiffusion-concentration product of the diffusing molecular oxygenis associated with the effect of carotenoids on the structural anddynamic properties of lipid membranes.15 Lutein and zeaxanthin are localized in the hydrophobic core of thelipid bilayer,16 and their orientationwith respect to the membrane plane depends upon a molecular configuration:all-trans xanthophylls span the membrane, while the13-cis xanthophylls are oriented in the membraneplane.8 On the other hand, the fact thatthe order parameter determined in the lipid bilayer does not changesignificantly with such a low xanthophyll concentration  suggestsa direct and specific role of lutein and zeaxanthin on the oxidationof OTP in membranes. Although the polyene chain is hydrophobic, itis possible that the incorporation of a xanthophyll molecule intothe lipid bilayer modifies the hydrophobic properties of the membranecore and reduces the penetration of oxygen molecules into the membrane.Importantly, the effect of xanthophylls in the 13-cis molecular configuration is much greater than in the case of all-trans, in the case of both zeaxanthin . Thus, a chemical reaction,such as lipid peroxidation, would be expected to occur more readilyin the center of the lipid bilayer. In general, our results indicatethat both the tested xanthophylls and both of their isomeric formsreduce the OTP in the center of the POPC bilayer  is comparable to the distance of polar groups localized ontwo opposite ends of the xanthophyll molecule in molecular configuration13-cis.18 This may suggestthat some fraction of the cis xanthophyll is orientedin the plane of the DMPC membrane or that the cis molecular configuration assures a monomeric state for membrane-boundxanthophylls as a result of a much higher aggregation threshold inthe lipid phase compared to trans carotenoids.20 Despite uncertainty about the exact mechanismunderlying this effect, it is important to note that 13-cis macular xanthophylls reduce the level of OTP in the hydrophobiccore of lipid membranes to a much greater extent than the all-trans form. It can therefore be stated that photoisomerizationof xanthophylls, observed in the retina under strong light conditions,acts as a regulatory mechanism preparing the entire system for protectionagainst photooxidative damage to photoreceptors and nerve cells. Inlight of the current and previous findings, it can be concluded thatthe photoisomerization of macular xanthophylls from the all-trans to 13-cis molecular configurationserves as a central regulatory mechanism important for not only theblue light filtration but also photoprotection manifested throughthe antioxidant activity realized by both quenching of singlet oxygenand creating a barrier for the penetration of molecular oxygen intothe membranes.The saturation recovery EPR technique can be appliedto monitorthe bimolecular collision rate between oxygen and the spin label byoxygen transport parameter (OTP) measurements. bilayer 4 and 5 a


Farming is essential work, but it suffers from very high injury and fatality rates. Machinery, including tractors, are a leading cause of serious injuries and fatalities to farmers and farm workers in many countries. Herein, we document the systematic development of an evidence-based, theory-informed behaviour change intervention to increase machine-related safety on farms. Intervention development progressed through four phases. Phase 1 defined the problem in behavioural terms based a review of the literature, Phase 2 identified candidate intervention targets through a series of focus groups guided by the Capability–Opportunity–Motivation–Behaviour (COM-B) model and Phase 3 employed expert and stakeholder consultation guided by the Behaviour Change Wheel (BCW) to consider potential target behaviours and intervention components and finalise the intervention content. Phase 4 finalised the evaluation strategies with a team of agricultural advisors who supported the rollout and identified outcome measures for the first trial. The target intervention was the identification of blind spots of farm tractors, and three priority target behaviours (farm safety practices) were identified. Following Phase 3, the intervention comprised four components that are delivered in a group-based, face-to-face session with farmers. In Phase 4, the acceptability, feasibility, and fidelity of these components were identified as the outcome measures for the first trial of the intervention. The four-phase systematic method detailed here constitutes an initial template for developing theory-based, stakeholder-driven, behaviour-change-based interventions targeting farmers and reporting such developments. Despite the global effort to improve farm safety, injury and fatality rates remain high in the agricultural sector ,2,3,4. FThe Medical Research Council (MRC) guidance for developing and evaluating complex interventions advocates for a systematic approach involving the best available evidence and appropriate theories . DespiteA recent systematic review by the authors indicated that there are growing numbers of studies utilising behaviour change theories such as the Theory of Planned Behaviour  and the Recent advancements in behavioural science have resulted in tools and techniques to develop interventions in a more systematic, evidence-based, theoretically informed way . The objThis study is part of a larger, multi-phase BeSafe project aimed at addressing the limitations of previous safety interventions targeting machine safety on farms. The study aimed to address gaps in the literature by developing an intervention using a systematic approach informed by the most relevant evidence, appropriate theories and stakeholder engagement.Previous studies exploring farmers’ safety behaviour employed behaviour models such as the Theory of Planned Behaviour (TPB), Capability, Opportunity, Motivation–Behaviour (COM-B) model and Health Belief Models to explain how farmers’ intentions, beliefs and attitudes are developed and evolve through the interactions between internal and external factors ,30,31,32As illustrated in This paper outlines the systematic process used to develop the BeSafe intervention and constitutes a template for developing similar interventions and reporting development decisions. This paper describes (a) the intervention development process (b) the relevant output of phase 1–3 and how it was methodically mapped to the BCW framework, and (3) the content of the resulting intervention. It will not discuss in detail the evaluation strategies and outcomes of the evaluations as they are outside the scope of the current paper and will be published separately in detail.Reporting of the intervention is in accordance with the TIDieR (Template for intervention description and replication) guidelines  and is aThe BeSafe project is a research programme funded by the Department of Agriculture, Ireland, and supported by the Health and Safety Authority (HSA) and Teagasc  to develop safety interventions to bring long-term changes to machine-related safety on farms. The current study commenced in October 2019. The research team consisted of a doctoral student (AS), two behavioural researchers (DOH. and JMS) and a Teagasc advisory team . The development of the BeSafe intervention involved four key phases, as illustrated in Intervention development was an iterative process guided by the intervention development guidelines provided by the BCW framework , includiEthical approval was obtained from the Research Ethics committee (REC) of the National University of Ireland, Galway (NUIG), before the commencement of focus groups (#2020.10.022) and co-design workshops (#2021.01.013). Written/verbal consent was obtained from all the participants involved in the study.The current paper was built on the evidence generated from the first three phases and described how the findings from these phases were methodically mapped onto the BCW framework and BCTTv1 to create lists of potential target behaviours and intervention components to address them. In this paper, the authors will explain how a behavioural change-based intervention to adopt preventive safety behaviours to address tractor-related blind spots at farms and improve farm safety was developed.What interventions have been employed to reduce machine-related incidents, injuries and fatalities among farmers?How effective are interventions designed to improve machine-related safety on farms?What BCTs and intervention functions comprise these interventions?What are the gaps in the current interventions?The first phase involved identifying and analysing the existing relevant evidence base, and examining the injury and fatality reports  to underA systematic review protocol was developed per the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines and registered (Registration number: CRD42020173834) on PROSPERO, the International Prospective Register of Systematic Reviews [In the review, as the first step, the general intervention categories were identified, such as safety education, financial assistance, regulations, etc. On further analysis, the behaviour change components targeting machine safety present in these interventions were identified and coded. Following the mapping of the components, the BCT used to implement these intervention functions was coded using the BCT taxonomy V1 . A narraReports of farm injuries and practices from HSA were examined to identify the potential broad categories of target population and behaviours for the intervention . Reviewi5.Explore participants’ experiences of tractor and quad bike safety.6.Identify the potential barriers and facilitators to safety behaviours.7.Identify potential active components to address these behaviours.In the next phase, between January and February 2021, we conducted a qualitative study involving four semi-structured focus groups with Irish farmers above 60 years of age. Purposive sampling  was adopA series of four focus group discussions conducted online via Skype ,46 by thBefore the commencement of this phase, the research team met to review Phase 1 and 2 findings and summarise the relevant findings. Subsequently, the potential target behaviours identified by the farmers were analysed and grouped into nine categories. The categorisation was guided by the findings from the review, survey reports  and safeThe current phase involves two steps: 1. Two co-design workshops with safety experts and stakeholders and 2. Feasibility screening with Teagasc advisory team.8.Identify potential target behaviours for the intervention.9.Identify barriers and enablers that are likely to influence these target behaviours. 10.Identify the potential intervention components and delivery methods.The current phase involved two stages involving one co-design workshop each, facilitated by AS, DOH and JMS. The session was conducted and recorded via the video conferencing tool, Zoom , with fiAs a first step, international farm safety experts with expertise in farm safety and farmer behaviours and stakeholders such as safety inspectors, farm representatives, tractor dealers and other farm organisation representatives were invited to participate in the workshops. They were assigned to one of the two sessions based on their expertise and availability. Identification of target behaviours11.Relevance to older Irish farmers.12.Effectively addressable through behavioural interventions.13.Feasibility to address them within the project constraints such as funding and available time. 14.Significant influence on risky farm practices.15.Influence more than one risky farm practices.The research team created a web-based rank order survey using the Gorilla survey builder . The surFor example, extensive paperwork as a barrier was given low priority since that is more relevant to policy-based or organisational-level intervention than behaviour-based intervention. Likewise, whenever a participant suggested a barrier or facilitator, facilitators encouraged them to discuss its impact on the older farmers, how it impacts them and whether it influences more than one safety behaviour. For example, farmers indicated that having a succession plan not only reduces the workload but also motivates investment in safety. However, regardless of meeting the criteria, all the barriers and facilitators identified by the workshop will be made available separately for future reference.Identification of potential intervention strategies and delivery methods.After the first workshop, the research team met to analyse and summarise the relevant findings. The second workshop had a different set of participants but with similar expertise and knowledge. The key evidence from previous phases, along with the recommendations formulated based on the BCW framework, was presented to the workshop participants. Participants were then asked to narrow down the potential barriers and facilitators to be addressed by the intervention and identify the potential intervention strategies and delivery methods to address them. The objectives of the screening were to finalise the selection of target behaviours, behaviour change techniques and modes of delivery.Once the key recommendations from the previous phases were consolidated  and mapped to the BCW framework, the research team added their ideas to the list of potential modes of delivery for each BCT. 16.Availability of evidence on the influence of the target behaviour on fatal incidents.17.Potentially modifiable at the farmer level.18.Farmers’ ability to carry out regardless of their age.19.Part of the recommended safer practices guidelines for operating the tractor safely.20.Relevant to every tractor-operating farmer regardless of age and farm type.From the selected target behaviours, specific target behaviours were selected and finalised for the intervention based on the following criteria:Once the target behaviours were finalised see , the focAcceptability: How likely will the farmers engage with the activity and were these intervention techniques familiar to them?Practicability: How likely is it to be completed in the allocated time, how much training is required, is it safe to perform, how many facilitators are required and can this be transitioned well for the large-scale rollout in the future?Affordability: How likely the interventions can be implemented within the allocated budget.Effectiveness: What are the expected outcomes of the trial? Do these intervention components effectively educate the participants on completing the target behaviours at home?Side effects/Safety: What are the other farm practices likely to be influenced by these interventions? Are there any negative effects expected to arise from the intervention?Equity: How far the intervention or part of the intervention likely to affect equity of access?After reaching a consensus on the finalised intervention components and implementation strategy within the BeSafe study team, the potential evaluation strategies were discussed. These discussions also determined the resources and funds available for the implementation and identified the ethical and bureaucratic approvals required for it. While the systematic and transparent reporting of methodology serves as a guide for developing interventions, a comprehensive evaluation is necessary to examine the feasibility and efficacy of the proposed behaviour change components. The systematic and transparent results presented in this paper will aid in conducting a thorough evaluation of the key components and their effectiveness. It was determined that the focus of the first trial would be on assessing the feasibility, fidelity and acceptability of the intervention components and their delivery. An intervention checklist, Direct observation, Audio recording of the study, Reported experience of the facilitators, Exit survey, SMS survey, Personal interviews. At the final stage, the outcome measures to evaluate the feasibility and determine the behaviour change, which included the completion of target behaviours, were determined. The finalisation of the evaluation was guided by a pre-determined feasibility checklist, fidelity framework and theoretical framework of acceptability, respectively, to ensure a systematic evaluation of the intervention. The following outcome measures were proposed:Evaluation strategies were identified for their potential to measure the feasibility, fidelity and acceptability of the active ingredients of the intervention, their delivery methods as well as the intervention as a whole. The tools for measurement were selected based on reliability, validity, availability and relevance. The potential list of recommended strategies was also judged against the subset of APEASE criteria considered previously. Other considerations were the suitability of digital tools such as online surveys for older participants and high attrition rates reported in farm interventions. Based on the findings from the study, a large-scale effectiveness trial will be recommended for the future stages of the intervention evaluation. 21.Studies often attempted to address a variety of farm risks via a single intervention.22.Multi-faceted interventions often underreported the intervention details, making it difficult to isolate the mechanism of change. 23.Very few interventions prioritised high accident-prone areas such as machines and livestock.24.Regardless of the significant role played by demographic factors such as age and farm types and the poor participation of vulnerable groups such as older farmers, interventions rarely focused on them ,52.25.Limited interventions reported the inclusion of stakeholders’ insights in the intervention development phase.The systematic review reiterated the findings of the previous reviews on the lack of theoretically informed behaviour change interventions, limiting the sustainability and efficacy of interventions ,12. AlthFindings from the review highlighted the need for tailored interventions that address vulnerable populations and more narrowly targeted interventions for specific farm safety practices. Ireland has an ageing workforce, with the average age of a farmer being fifty-seven. The Irish farm safety reports that 45% of the fatal incidents on the farms involve farmers 65 years of age or older and they are reported to be eight times more vulnerable to fatal injuries than other working sectors . While rWhile a few studies employed behaviour change theories to develop interventions, most of the studies failed to report the intervention development process and components in detail. In addition, even while the intervention details were available, they were not described using the behavioural change terminologies. Hence, the authors identified the specific intervention components targeted at machine safety, analysed their descriptions, and then retrospectively coded them using the BCT taxonomy. Farmers identified the risky practices prevalent in the Irish farming communities along with the prevalent and potential safety practices. They discussed the types of facilitators and barriers influencing the adoption of these practices. Some of these factors were specific to certain practices, and some were related to farm safety in general. Several inductive themes related to the challenges of adopting and adhering to safety practices were identified. They were further analysed in the context of the COM-B sub-domains .Several of these barriers were consistent with the findings from the literature. For example, participants repeatedly highlighted rushing and lack of situational awareness as major contributors to farm incidents. On further exploration, some common risky practices associated with them were identified, such as poor maintenance of the power take-off (PTO) shaft and its protective covers, operating the tractor without checking the perimeter and climbing off the tractor without engaging the break. However, older farmers also talked about how the factors such as their perceived self-efficacy and perceived risk associated with the tasks influenced their decision to continue or modify their farm practices as they grew older. Several participants discussed discontinuing using quad bikes since they perceived them as dangerous machinery and found them challenging to operate. The study also explored the farmers’ attitudes towards the potential BCTs identified in the systematic review. For example, the participants were asked about their attitudes towards mentoring programs and farm discussion groups, and they shared their recommendations for potential intervention strategies. The research team met to review the focus group findings and summarised the relevant findings from phases 1 and 2. Identifying specific barriers and facilitators and mapping them to the theoretical domain informed the identification of potentially effective intervention functions and behaviour change components. The focus group participants also suggested a few target behaviours and intervention strategies to address them, and the research team mapped them to the BCW intervention functions and BCTs using the BCW framework and BCT taxonomy V1, respectively .Identification of target behavioursThe relevant findings from the previous phases and the web-based survey on target behaviour categories were shared among all participants a week before the first session. Once the participants provided their consent and completed the survey by ranking the candidate behavioural change categories in terms of their relative priority, the top two were identified. Eleven participants completed the survey and selected the following two categories as the most appropriate ones: (1) allocating attention to machinery operation and the local environment and (2) installing and using appropriate safety devices on machinery.After participants prioritised the appropriate target behaviours for the intervention via survey, the workshop started by exploring specific target behaviours under the shortlisted categories that could be potentially improved through behaviour-based interventions. While considering the specific target behaviours to be considered under the first category, participants highlighted the importance of self-evaluation of risks by farmers. They discussed increasing the habitual risk assessment in the immediate surroundings to ensure the tractor is in working order and that older people and children are not in the working area. While discussing the second category, participants discussed fitting the tractor with appropriate safety devices such as cameras and mirrors to improve visibility and awareness. They have also noted the significance of choosing appropriate and fitting implements and safety devices for farm operations; for example, the right-sized trailer and well-fitted protection covers and PPEs. After identifying the potential specific target behaviours, associated barriers and facilitators that can potentially be addressed by behaviour change-based interventions were discussed. Current participants reiterated the findings from the focus group on the prevalence of rushing and how it prompts the farmers to overlook the immediate dangers such as maintaining good conditions of equipment and a sensible pace for tractor operations. They also pointed out that raising awareness about specific risks associated with each task can encourage participants to be more alert. Likewise, the focus group participants also highlighted how the financial and time constraints along with the voluntary nature of the current safety regulations often encourage the farmers to prioritise productivity over safety. These behavioural determinants were identified as relevant for both categories.While discussing the heterogeneous and seasonal nature of tasks, the participants raised the importance of seasonal safety messages and campaigns. Beyond the messages from the safety authorities, they described how personal stories and farm visits by friends highly resonate with their fellow farmers. Identification of potential intervention strategies and delivery methods.The summarised findings and recommendations that emerged from the previous phases were shared among the participants before the online session. The first half of the discussion focused on identifying potential barriers and facilitators that can be effectively addressed through behaviour-based interventions. While the financial constraints and voluntary nature of the regulations were major concerns, the consensus was that they were more effectively addressable by financial and regulatory-based interventions. Participants agreed that a lack of knowledge is a major barrier and can be effectively tackled through targeted safety messages. While a few participants recommended peer-to-peer learning and buddy systems as effective strategies, others proposed marketing campaigns. One of the safety researchers explained her experience with implementing personalised safety messages through marketing campaigns. However, a few participants did raise concerns about the effectiveness of individual-level behaviour change strategies given the isolated nature of the farms and frequently reported risk habituation among farmers . In the The sample presentations and surveys used for the workshops are available under the BeSafe profile in the OSF . 26.The length of the intervention program will be less than four hours.27.Participants from all four major farm types will be invited to the program.28.The ratio of older and younger farmers will be 50:50.As the final step of the intervention design, multiple follow-up meetings were conducted among the authors. The intervention was designed for older farmers, but Teagasc brought up the possibility of including the younger adults in the first trial. It was agreed that, by including younger farmers, the trial could examine whether the intervention was suitable for a wider age range and whether the outcomes achieved among older farmers can be generalizable to younger farmers as well. The different perspectives and experiences of younger and older farmers regarding their health and wellbeing will be investigated since they may reveal new insights and possibilities for tailoring the intervention to meet the needs of different age groups. Hence, under the guidance of the Teagasc advisory team, it was decided that, for the first trial:As summarised in The summary of the findings regarding the barriers and facilitators considered at various stages is illustrated in Based on the findings from the first three phases, intervention functions, education, training, enablement and persuasion were finalised for the interventions. As noted in As detailed in The detailed description of the trial design, evaluation strategies and data collection tools are available in the study protocol (pre-print)  and therThis paper describes the systematic development of an intervention to improve tractor-related safety on farms and aims to fill the lack of theoretically based and adequately described behaviour change-based interventions in the relevant literature ,12,60. TEvidence suggests that by targeting specific behaviour change mediators, the potential effectiveness of the intervention is likely to be increased . TherefoThe decision processes, behaviours and environmental conditions leading up to a specific farm fatal incident are complex. Hence, it is unlikely that adding one safety pre-check practice to farmers’ habits is not enough to reduce the potential dangers associated with blind spots. A combination of activities involving environment re-structuring, and raising the awareness of farmers and others farm workers and family members are required to improve the safety odds. That is why, while one of the target behaviours focused on improving the adoption of a safety pre-check into their daily practices, the other two target behaviours focused on setting up the no-visibility zone and performing the blind spot demonstration at their farms with family members or friends. While reviewing the existing interventions, it was noted that education and training-based interventions often target farmers alone, even though farm surveys  indicateBefore evaluating the effectiveness of a new intervention or piloting on a larger scale, it is recommended to assess the feasibility, fidelity and acceptability of the intervention . A feasiThe key findings and recommendations that will be published separately can inform future studies on the potential target behaviours, specific barriers and facilitators influencing them and potential BCTs that can be used to address and promote them effectively. The main strength of the study is the systematic development of intervention through evidence-based, theoretically informed phases and strong stakeholder engagement. This enabled transparent reporting and may enable the replication or adoption of the intervention or one of its ingredients in future studies. This is one of the few studies that addressed the older farmers’ needs while designing the intervention and ensured the participation of farmers from different age groups, thus making it suitable for both young and older farmers. Educational interventions are one of the most common strategies used by farm safety programmes; however, for the current study, the choices of the intervention components and their delivery modes were informed by the theoretical framework underpinned by behavioural models, local contexts and target population. Rothman  observedThe intervention focuses on a selected few target behaviours targeting the safety related to blind spots hence addressing the influencing factors associated with it. However, by describing the process in a systematic manner and reporting the findings in detail through multiple papers, the study added detailed context-specific information on prevailing machine operation and safety-related practices, factors influencing them and guidance on developing similar interventions based on the findings of the current study.While the BCW framework gained popularity in public health research, there is limited information available on its adoption of it in the farm literature. Hence, there was a lack of available evidence to decide on the best approach to select the best target behaviours and operationalise the BCTs from the potential list of farm practices and intervention strategies identified through literature and interactions with experts and stakeholders. Therefore, the final draft of the target behaviours, selection, operationalisation and packing of intervention components were based on the researchers’ experience, feedback from the advisory team and what is likely feasible within the current research context. As observed by Cadogan et al. , these bAll the participants who contributed to the various stages of the studies attended them voluntarily. Previous studies reported that the voluntary nature of these studies often encourages only the already safety-conscious farmers to participate . As a reThe study demonstrated the integration of various available evidence, such as reviews, field reports, stakeholder perspectives, and behaviour change theories, within an appropriate framework to provide a structure for integrating evidence and identifying and implementing the most appropriate behaviour change strategies. Detailed reporting of the intervention development can encourage future farm researchers to better document and report their own development process along with their key findings, thus generating a body of evidence that can be adopted as a whole or in parts by the safety agencies and researchers for developing farm safety programmes. The ongoing feasibility study will assess the potential of the intervention and modification required before progressing to a large-scale effectiveness study.


Background: The COVID-19 pandemic has led to millions of documented deaths worldwide, with diverse distribution among countries. Surprisingly, Bulgaria, a middle-income European Union member state, ranked highest in COVID-19 mortality. This study aims to assess whether Bulgarian cancer patients experienced a higher relative risk (RR) of death compared to the general Bulgarian population during the pandemic. Materials and Methods: Data from the Bulgarian National Statistical Institute and the Bulgarian National Cancer Registry were analyzed to estimate monthly RR of death in cancer patients compared to the general population before and during the first two years of the pandemic. The impact of the COVID-19 waves and predominant SARS-CoV-2 variants on RR was evaluated on various cancer types and age groups using a multiple linear regression approach. Results: During the COVID-19 waves, both the general population and cancer patients experienced a significant increase in mortality rates. Surprisingly, the RR of death in cancer patients was lower during pandemic waves. The results from the statistical modeling revealed a significant association between the COVID-19 waves and reduced RR for all cancer patients. Notably, the effect was more pronounced during waves associated with the Alpha and Delta variants. The results also showed varying impacts of the COVID-19 waves on RR when we analyzed subsamples of data grouped depending on the cancer type, age and sex. Conclusions: Despite increased overall mortality in Bulgarian cancer patients during the pandemic, the RR of death was lower compared to the Bulgarian general population, indicating that protective measures were relatively effective in this vulnerable group. This study underscores the importance of implementing and encouraging preventive measures, especially in cancer patients, to mitigate the impact of future viral pandemics and reduce excess mortality. It was initially perceived that at an individual level mortality would be highly dependent on socio-demographic factors [https://coronavirus.jhu.edu/data/mortality, accessed on 2 September 2023). Bulgaria was also shown to be one of the countries with highest number of excess death cases during the first two years of COVID-19 pandemic with 647.3 excess deaths per 100,000 inhabitants [https://ecis.jrc.ec.europa.eu/, accessed on 10 September 2023) the age-adjusted cancer incidence and mortality in Bulgaria in 2020 were 458.0 and 258.4 per 100,000 inhabitants, respectively. These rates are lower than the European average but the same report showed that the 5 year relative survival of cancer patients is between 5% and 15% lower than the European average depending on sex and age group. Therefore, given the fact that cancer patients have been shown to be at increased risk for poor outcomes from COVID-19 [As of the end of May 2023 the COVID-19 pandemic led to almost 7,000,000 documented deaths worldwide  of death in Bulgarian cancer patients immediately before and during the first two years of the COVID-19 pandemic. For the purpose of those analyses, we used publicly available data from the Bulgarian National Statistical Institute (NSI) and the Bulgarian National Cancer Registry (BNCR).https://infostat.nsi.bg/infostat/pages/external/login.jsf) (accessed on 1 February 2023). Monthly aggregate data regarding the newly diagnosed and dead cancer patients were obtained from the Bulgarian National Cancer Registry (BNCR)  covering the abovementioned period (last updated 1 February 2023). Data from the BNCR were stratified by age at diagnosis, sex and major entities. As BNCR was not able to provide the age at death or last follow-up we defined overlapping age groups at diagnosis as: all ages (designated as 0+), older than 19 years (designated as 19+), older than 39 years (designated as 19+) and older than 59 years (designated as 59+). The main entities groups were defined based on ICO-0-2 codes as follows: colorectal cancer (CRC) (C18–C21); acute myeloid leukemia (AML) ; lung cancer (LC) (C34); multiple myeloma (MM) (C90); ovarian cancer (OC) (C56); breast cancer (BC) (C50); prostate cancer (PC) (C61); endometrial cancer (EC) (C54.1); cervical cancer (CC) (C53); malignant lymphoma (ML) ; and chronic myeloid leukemia (CML) (C92.1).We obtained data regarding monthly and annual mortality for both sexes and all ages in Bulgaria between 1 January 2016 and 31 December 2021 from the data portal of the Bulgarian National Statistical Institute  per age and sex group was directly obtained from the NSI data portal. Monthly mortality in cancer patients required additional manipulations of the raw data provided by the BNCR which consist of the raw counts of registered cases and the number of deaths per month for each gender, age group and ICO-O-2 code described above. We started with the calculation of the average number of the registered patients in each patients’ subgroup formed by the cancer type, sex and age. Subsequently, the number of death cases per month was divided by the average number of the registered patients per group, adjusted for the length of the month and year (in days) and multiplied by 1000 to obtain the monthly mortality in the different cancer patients’ groups. The relative risk of death in every cancer patients’ group compared to the general population for a given month was calculated as the ratio of the proportions of the death cases  in both cohorts of individuals  . For theforestmodel and ggpubr.We modeled the relative risk of death in cancer patients compared to the general population using multiple linear regressions. The predictors are the presence or absence of a COVID-19 wave, the predominant SARS-CoV-2 variant in Bulgaria and the month of the year, all these variables were considered as categorical. This approach allows for analysis of the seasonality in the data assuming the month of the year as a fixed effect . InformaWe initially estimated and plotted the monthly death rates in Bulgaria for the general population and for the registered cancer patients merged and split by gender . As showp-value = 0.022) and the effect was also significant for Alpha and Delta variant-associated waves . We defined several groups with different lineage origins and distinct clinical courses. We observed an increase in the mortality rate in lymphoma patients during the COVID-19 waves and minor effect in MM patients whereas for CML and AML there was no obvious effect on mortality rate .Statistical analyses confirmed the observation from the graphics that the relative risk is not affected by the presence of a COVID-19 wave . There wBulgaria had one of the leading positions in the ranking of the highest mortality from COVID-19 worldwide. We investigated if the mortality in one subgroup of the general Bulgarian population, namely the cancer patients, was proportional to the mortality in the general population before and during the first two years of COVID-19 (the period studied is from the beginning of 2016 till the end of 2022). In this study we analyzed data from the Bulgarian National Statistical Institute and the Bulgarian National Cancer Registry in order to estimate the monthly RR of death in cancer patients compared to the Bulgarian general population. Using multiple linear regression models for different subsamples of cancer patients depending on their cancer type, age and sex, we estimated the effects of the presence of a COVID-19 wave and the predominant SARS-CoV-2 variant in Bulgaria, controlling for the seasonal effect on mortality.Mortality in the general population has a clear seasonality pattern with significant increase during the cold months of the year . This miWe focused our study on Bulgarian cancer patients with the main goal to evaluate the dynamics of the relative risk of death among them before and during the first two years of the COVID-19 pandemic. Bulgaria was unique case for the management of the COVID-19 pandemic with suppression of the initial spread and waves with very restrictive measures including complete lockdown in March–May 2020 . HoweverBased on that and the limited resources for oncology care in the country we questioned whether the relative risk of death in cancer patients was identical or even higher than in the general population. Surprisingly, we observed a statistically significant lower RR of death in the cancer patients for all age groups and for both sexes during the COVID-19 waves in the country. Indeed, the RR of death in cancer patients was lower in the winter months even before the pandemic. This suggested that even though there was excess mortality in cancer patients during those periods it was not proportionate to the mortality in the general population. This observation directly suggests that cancer patients were more protected than the general population. There is no reliable data source which can provide information regarding the incidence of COVID-19 in cancer patients. Lower incidence of COVID-19 in those patients because of stricter adherence to general preventive measures may have accounted for a lower RR of death in 2020. On the other hand, the more rapid dissemination of vaccination and less vaccine hesitancy among cancer patients in 2021 might have contributed to the prevention of COVID-19 deaths in 2021. In support of that hypothesis we observed a tendency for a lower relative risk of death in cancer patients during the Delta variant-dominated waves in the second half of 2021 in comparison to Alpha variant-dominated ones in the first half of 2021.Expectedly, the effect of the COVID-19 waves on mortality differed between cancer types. It was most pronounced in male lung cancer patients suggesting that those patients were probably better protected during the waves. Less aggressive cancer such as colorectal cancer was associated with lower relative risk of death during the waves. Breast and ovarian cancers showed a similar pattern of relative risk reduction especially with later waves, which was more pronounced for BC patients. One cannot exclude the possibility that long-term usage of selective estrogen receptors (SERMs) has played a protective role in BC survivors suffering from COVID-19 ,27,28. OInterestingly, males with prostate cancer who oftentimes require chronic long-term hormonal therapy had a significantly lower relative risk of death during the COVID-19 waves. Indeed it was proposed that androgens may play a role in COVID-19 pathogenesis through the androgen-regulated transmembrane protease, serine 2 (TMPRSS2), which also plays a critical role in SARS-CoV-2-host cell membrane fusion . AndrogeIn general, patients with hematological malignancies have the highest levels of immune suppression because of the nature of the diseases directly affecting the immune system as well as because of the usage of highly myelosuppressive therapies. We analyzed four groups of patients with hematological malignancies as they differ by the natural course of the disease and available therapeutic approaches . CML patients, for example, showed a similar pattern to the one observed for endometrial cancer patients without any effect of the COVID-19 waves on the RR of death. This is because CML patients have a near-normal quality of life on chronic therapy with tyrosine kinase inhibitors  and are Our study has some limitations based on the type of source data obtained. We only had aggregate data and no individual data available, such as actual age at death, the cause of death or vaccination status of patients. We compensated for the inability to perform an age-adjusted calculation of mortality and relative risk by analyzing overlapping groups based on their age at diagnosis. One can also speculate that delayed diagnosis and registry reporting of new cases might have affected the overall number of cancer cases during that period. Delayed diagnosis and reporting might be a real phenomenon, however, we analyzed a relatively long period and used an average number of registered cancer patients over the year which would compensate partly for delayed registration. Besides, all cases registered based on death certificates are captured in a timely manner and therefore the chance of under-estimation of the relative risk is avoided. Of course, if we had individual data available from cancer patients with their vaccination status and cause of death we could have directly assessed the effect of vaccination on COVID-19 and other causes mortality but this was obviously impossible and remained beyond the scope of this work.The study raises the interesting question of whether any specific protective measures were more efficient among cancer patients. As described above this question could not be addressed directly as we did not have specific data regarding the adherence of cancer patients to specific measures. It is rational to speculate that as the relative risk of death was lower with the later COVID-19 waves it was a combination of measures that contributed to this outcome. Firstly, by the second half of 2020 the vaccination coverage might have been higher among cancer patients and therefore the disease would have been less frequent and less severe in that group. Secondly, cancer patients might have more strictly followed the principles of personal protection than the people in the general population even when the latter had poorer adherence to those measures, thereby reducing the overall number of cases and deaths. Finally, cancer patients might have been hospitalized earlier than otherwise healthy individuals, which could also contribute to a lower relative risk of death. Assessment of all these explanations requires more granular individual level data for death cases in the general population and the group of cancer patients.In conclusion, our comprehensive analysis highlights that cancer patients in Bulgaria faced increased overall mortality during the initial two years of the COVID-19 pandemic. However, the intriguing finding is that the relative risk of death in cancer patients was surprisingly lower compared to the general population and the same analyses applied to different subgroups categorized by cancer type, age and sex showed similar findings for some of the cohorts considered. This observation strongly suggests that a substantial proportion of Bulgarian cancer patients diligently followed and adhered to general protective measures, including vaccination.Regrettably, this lower RR in cancer patients implies that a significant portion of the excessive mortality in the Bulgarian general population could have been mitigated if similar protective measures were widely embraced and implemented. The results underscore the critical importance of public health initiatives that prioritize the protection of vulnerable groups, such as cancer patients, during future health crises and pandemics.Moving forward, targeted efforts and tailored interventions should be put in place to ensure that high-risk populations receive adequate support and protection during any public health emergency. This includes not only emphasizing general preventive measures but also streamlining vaccination strategies and promoting healthcare access for vulnerable individuals. By proactively safeguarding those at higher risk, we can strive to reduce overall mortality rates and enhance the resilience of our healthcare systems in the face of future challenges.


Advances in modern medicine coupled with the advent of smart technologies are allowing people throughout the world to live longer, contributing towards an aged society. At the biological level, aging involves the accumulation of a wide variety of molecular and cellular damage over time. These changes predispose the elderly to irreversible aging-associated conditions such as cancers, neurodegenerative diseases, bone disorders, heart disorders, diabetes, etc .Adult stem cells (ASCs) present in various tissues play a crucial role in maintaining tissue homeostasis. One of the primary reasons for the functional decline of tissue homeostasis that accompanies aging is the depletion of the stem cell pool in the adult tissue and the simultaneous changes in the stem cell niche and the systemic microenvironment. Together these changes impair the regenerative capacity of ASCs . Hence, Farahzadi et al. have discussed the various niche-targeting strategies for promoting the rejuvenation of aged stem cells. They start by underscoring the importance of the stem cell niche in regulating the fate and behaviour of the stem cells that impacts tissue homeostasis, aging, and disease onset and progression. Finally, they advocate targeting the stem cell niche for developing future therapeutic applications in stem cell transplantation and regenerative medicine.The extracellular matrix, signaling pathways, various soluble factors, and biochemical elements present in the microenvironment of ASCs are altered by aging. The interaction of ASCs with such an altered microenvironment leads to impaired stem cell functionality and loss of tissue homeostasis. In this review article, Sapède et al. have shown that the regeneration of chondrocytes is mediated via the Nrg1/ErbB signaling pathway. Upon knockdown of Nrg1 and inhibition of ErbB3/2 receptors, the chondrocytes lose their regenerative potential suggesting that the Nrg1/ErbB pathway could be explored as an alternative target for enhancing the regenerative potential of cartilage in other species as well.Irreversible cartilage deterioration and incapacitating joint diseases are commonly associated with aging. Since cartilage has a limited potential to repair itself, promoting the growth of cartilage in patients is a major challenge in regenerative medicine. Using zebrafish as a model system, De La Torre et al. demonstrate the regenerative potential of decidua-derived mesenchymal stromal cells (DMSCs) using the rat SUI model. When DMSCs are cocultured in vitro with the patient-derived myofibroblasts, there is decreased expression of inflammatory cytokines and senescence-related proteins in the myofibroblasts, suggesting DMSCs as a potential therapeutic against SUI.Aging alters the structure of the extracellular matrix in the anterior wall of the pelvic tissues, thereby inducing stress urinary incontinence (SUI). In this original research article, Kulkarni et al. states that early growth response factor 1 (Egr1) is one of the key transcription factors regulating HSC proliferation and their localization in the bone marrow niche. Downregulation of Egr1 improves the proliferation and differentiation of HSCs whereas overexpression of Egr1 leads to inflammation-mediated aging in HSCs. Dysregulation of Egr1 is however associated with hematological malignancies such as acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and chronic myelogenous leukemia (CML). Targeting EGR1 is an encouraging alternative strategy for the rejuvenation of aged HSCs.Age-mediated changes in the hematopoietic stem cells (HSCs) microenvironment alter the interaction between the HSCs and the bone marrow niche, thereby affecting the functionality of HSCs. Vitale et al. have reported the role of CMA in promoting the self-renewal and differentiation potential of embryonic stem cells, its role in the rejuvenation of aged HSCs, and in the regulation of immunosuppressive and differentiation properties of MSCs. They further discuss the significance of CMA to rejuvenate aged stem cells and their application in regenerative medicine.Chaperone-mediated autophagy (CMA) has emerged as a key mechanism for improving the regenerative potential of stem cells by regulating epigenetic, transcriptional, and differentiation factors in them. Here Nugud et al. have classified biomaterials based on their source, bioactivity, different biological effects, and their role in improving the rejuvenation and differentiation potential of ASCs. Such an approach would help in developing biological substitutes or functional constructs to fix defects in tissues or organs. This review highlights the significance of using biomaterials for stem cell differentiation strategies, thereby enhancing the field of regenerative medicine.Numerous biomaterials have been explored to improve the ability of stem cells to expand and differentiate into various lineages.