Background and objectiveThe global HIV epidemic has evolved in the past 30 years with a decline in mortality and morbidity and improved survival since the introduction of antiretroviral therapy (ART). However, this has brought on new challenges through the emergence of non-communicable disease (NCD) as a pandemic at par with, if not more serious than, HIV, and patients well maintained on ART are now faced with the increased risk of developing NCDs such as hypertension, which also require lifelong therapy. This study was designed to determine the burden of hypertension in patients under HIV care in Masvingo province, Zimbabwe.MethodsA retrospective cohort study was conducted in six districts of Masvingo province based on the data collected from the electronic Patient Monitoring System (ePMS), along with an analysis of secondary data. Of the 94,821 records gathered, 877 met the inclusion criteria to be included in the study. Data were analyzed using Microsoft Excel and Stata statistical software and statistical analysis was performed using the χ2 test.ResultsThe study revealed a hypertension prevalence of 7.64% among the 877 patients analyzed and the independent risk factors for the development of hypertension were determined to be the age of patients, with a one-year increase in age resulting in an 8% increase in the risk of developing hypertension, and the duration on ART, with a one-year increase on ART duration increasing the risk of hypertension by 27%, and an increase in BMI by a factor of 1 increasing the risk of getting hypertension by 9%.ConclusionOur findings showed that there are patients who have both hypertension and HIV on ART care, and they would need to be managed for both. There is a need for improved data collection of important variables that improve the quality of care of clients. Clinical management of HIV needs to evolve with the evolving needs of patients and NCD care has to be factored in. HIV remains a major global public health problem. According to the World Health Organization (WHO), an estimated 36.7 million adults are living with HIV while 1.3 million acquired it in 2021 alone globally [A concerning prevalence of non-communicable diseases (NCDs), such as diabetes mellitus, cardiovascular diseases, and hypertension among ALWHIV has been reported in several studies -7. WhileHypertension is defined by WHO as an elevated systolic blood pressure ≥140 mmHg and diastolic blood pressure ≥ 90 mmHg, and it is a major cause of premature death . WHO estThis study aimed to determine the burden of hypertension and its known risk factors like BMI, diabetes mellitus, renal and liver diseases, and the ART regimen in ALWHIV on ART and which of the risk factors contribute to the burden of hypertension. The primary objective was to determine the burden of hypertension in HIV-infected adults on ART in Masvingo province, Zimbabwe. The secondary objectives were to determine the prevalence of Hypertension in HIV-infected adults on ART, to describe the demographic characteristics of the HIV-infected adults on ART, and to analyze the factors (correlates) that predispose HIV-infected adults to hypertension.Ethical approval and study settingWe obtained approval from the Ethical Board of the Provincial Medical Directorate for Masvingo province. This study utilized secondary data and a retrospective cohort analysis was carried out. The setting was Masvingo province, which has 165 medical facilities that offer ART in the public health system.Study designThe study involved a retrospective cohort analysis of data collected in the electronic Patient Monitoring System (ePMS). The sampling frame was all adults in the ePMS receiving HIV care and treatment in Masvingo province’s six districts, which totaled 96,821 individuals. The study population comprised adults in Masvingo province diagnosed with HIV and who started ART between the 1st of January 2014 and the 31st of December 2022 and whose treatment data including blood pressure values were recorded in ePMS. The resultant sample after excluding all records without BP values amounted to 877 records. The inclusion and exclusion criteria are detailed below:Inclusion criteriaThe inclusion criteria were as follows: all HIV-positive patients who have commenced treatment and are at least 18 years of age, ART patients currently receiving active treatment, and patients with data including BP values and duration on ART recorded in the ePMS database.Exclusion criteriaThe exclusion criteria were as follows: ART patients below the age of 18 years, HIV-positive patients who have not started ART treatment, and patients whose data including BP values and duration on ART were not recorded in the ePMS database.As shown in Table Data management and analysisData were retrieved from ePMS and refined using Excel and STATA. Available case analyses were used to account for the missing data. The major variables that were used in analyses were time spent on ART and hypertension status. Any record that did not have these two was not used in the analyses. Categorical variables were compared by using the χ2 test. Multiple logistic regression analysis was performed to enable the researcher to identify the significant covariates that had a bearing on explaining the association of hypertension among people on ART.Effect modification was checked for all the covariates that were used in the model since the model had a few variables of interest that the researcher had obtained from the ePMS database. This was done by including product terms of each combination of the variables present in the logistic regression model. Upon variable selection (by backward selection method), marital status was dropped and hence not included in the final logistic regression model and subsequently not tested for effect modification. No effect modifiers were observed, and hence the model was reduced to once without any product terms. Descriptive analyses for main study variables, CHI square tests, and logistic regression analysis were carried out by using STATA.A total of 877 records were included in the analysis. The descriptive statistics of patients on active ART treatment based on covariates are presented in Table Among the 877 patients with full information on hypertension status and time lived on ART, the majority were from the Masvingo district (33.3%) followed by the Chiredzi district (26.45%), with the least number of patients hailing from the Mwenezi district (4.1%). The minimum age among the patients in the study was 18 years while the maximum was 81 years. The interquartile range (IQR) for age was 14 with the age distribution symmetric with the mean median and mode all being 40 years of age. The majority of the patients were in the age group 36-45 years (37.4%) followed by those in the 26-35-year age group (25.31%), while the least number was in the age group above 65 years (2.96%).There were more females (63.17%) than males (36.83%) in the analyzed sample. The majority of the clients were married (65.68%) followed by those that are divorced (14.37%) and those that were widowed (10.49%), and only 9.46% of the patients were single. The BMI of the patients was classified as follows: <18.5: underweight; between 18.5 and <25: normal; between 15 and <30: overweight; 30 and above: obese.The majority of patients had a normal BMI (50.5%), with 29.99% being overweight, 8.67% being obese, and 6.84% being underweight. The duration of ART ranged from 0.2 years to nine years in the patients analyzed with a mean of 5.3 years, median of 5.6 years, and the mode being with an interquartile range of three years. Most of the patients in the study had spent six to nine years (43.79%) on ART, followed by those who had spent 4-<6 years (31.13%) and those who had spent from 2 up to <4 years (16.08%); only 9.01% had spent <2 years on ART. The prevalence of hypertension among people living with HIV and on ART in this sample was 7.64% . BMI was found to be associated with a higher risk of hypertension and the observed prevalence was three times higher in obese patients compared to those with normal weight. The prevalence of hypertension was 18.2% in obese patients compared to 6.2% in patients with normal weight. Moreover, there was an increased prevalence of hypertension in patients who had spent more time on ART. The prevalence was found to be 9.52% and 9.90% in patients on ART for five to six and seven to nine years respectively.Logistic regressionBefore the forward selection method on the initial regression model in which all variables with p<0.25 were retained, in the final multivariate regression model, only marital status was dropped while sex, age, BMI, and district were retained. The researchers also included time spent on ART in the final model as it was one of the variables of interest for the topic.The final multivariate logistic regression model identified age as a highly significant risk factor for hypertension among people on ART . The risk of hypertension increases by approximately 8% with a one-year increase in age. BMI , and an increase in BMI by a factor of 1 increasing the risk of getting hypertension by 9%. Time spent on ART treatment was also found to be significantly associated with hypertension . This means that an increase in one year spent on ART was found to be associated with a 21% increase in the risk of hypertension. Sex and district were found not to be significantly associated with hypertension after controlling for other covariates in the model.The prevalence of hypertension among ALWHIV is not well documented but believed to be higher than among those who are not infected by HIV because of the effects of HIV infection and the adverse effects of ART . A revieIn Zimbabwe, there have been only a few studies to estimate the prevalence of hypertension or NCDs among HIV-infected adults resulting in a paucity of data on the actual burden of NCDs and HIV comorbidity, similar to many other low to medium-income countries ,19. A stA literature review on hypertension in HIV-infected adults by Fahme et al. demonstrated that ART may mediate hypertension in ALWHIV; for instance, protease Inhibitors (PIs) can result in peripheral and central adiposity accumulation and lipodystrophy linked to hypertension . LipoatrThis study aimed to determine the burden of hypertension in HIV-infected clients on ART. The prevalence of hypertension in people on ART is comparable to the overall prevalence of hypertension among the general population in Zimbabwe . The resAn increase in age was found to be a risk factor for hypertension among people on ART treatment. The steady increase observed in the prevalence of hypertension in those who are 65 years and above, i.e., 30.77% from a prevalence of 1.33% in those 18-25 years of age, is consistent with the findings from studies in other parts of the world: a study from the United States has reported that the prevalence of hypertension is 7% in those 18-39 years of age and rises to about 65% in those who are 60 years old and above . A studyIt is well known that the socioeconomic situation in Zimbabwe has also resulted in a significant brain drain in the health sector due to experienced nurses leaving the country in large numbers, thereby resulting in a shortage of nurses in the health facilities with a consequent increase in workload. This results in poor documentation, primarily due to the lack of experience among the available staff as well as the pressure of work as, in the public health system, the primary source documents are the patient files and not the ePMS system, and most nurses and clinicians hold the belief that this represents extra work. This situation has been worsened by the recent introduction of the Electronic Health Records system, which is further aggravating the workload. It is a separate system that the government is introducing with a view to improving patient monitoring and clinical efficiency. The ePMS system does not function properly all the time and depends on the availability of trained staff, electricity, and functional laptops; thus, the information available is frequently complete and there have been instances of data being not captured for long periods, resulting in a need for back-capturing of data, which makes it difficult to have the accurate and correct information.Studies on ART patients noting their cardiometabolic risk have reported an increased risk of hypertension with an increase in the duration of ART. This has been attributed to the elevation of metabolic agents such as total cholesterol, low-density lipoproteins, and high-density lipoproteins. However, it has also been noted that certain antiretrovirals like PIs reduce the risk of hypertension and more time spent on these would also reduce the risk of developing hypertension, which contrasts with some other studies reporting that being on PIs increases lipodystrophy which would, in turn, increase the risk of hypertension. Because patients can be on different medications, due to factors such as availability, patient toxicities, or even for the purpose of controlling control viremia, it is important that clinicians know what medications their clients are on as they may increase the risk of hypertension as well as cardiovascular risk factors.Several studies have found that there is a significant difference in the prevalence of hypertension between males and females with males having a higher prevalence than females overall; however, in this study, there was no significant difference between the prevalence of hypertension between males and females. In a study conducted at Parirenyatwa Hospital in Zimbabwe, there was a higher prevalence of hypertension in males (31.6%) than in females (28.1%) though the difference was not statistically significant ,25,26.Obesity is a recognized independent risk factor for the development of hypertension and cardiovascular disease, and this has been reinforced in our study where, on univariate and multivariate analyses, obesity remained a significant risk factor for hypertension . ObesityAn increase in BMI was also found to be associated with an increased risk of hypertension among people on ART treatment. Significantly, upon a separate analysis, an increase in BMI from lower to higher categories was also found to be associated with an increase in years lived on ART, especially among patients with a good adherence history. This is a point worth noting because overweight and obesity are known risk factors for hypertension. Thus, if chronic ART intake is associated with a BMI category increase, it follows that chronic ART intake is also indirectly associated with hypertension. This could be crucial for hypertension prevention and management among ART patients, especially with regard to program planning and implementation .StrengthsThe study adds to the body of knowledge on hypertension in HIV care. The sample size of 877 was large enough to produce valid results and thus the findings of this study can be used to devise policies on HIV care and management and improve the quality of care of patients in the public healthcare system.LimitationsSome biases may have crept in due to the retrospective nature of the study design. An effort to reduce some of the biases was made by excluding patients with incomplete demographic, treatment, and clinical data or any other data that we deemed vital for the study. We also excluded patients who were no longer receiving active ART. A small number of patients with missing records were not included in the study. The other major limitation pertains to the data availability in the ePMS database. There are very few variables recorded in the surveillance system, and hence we could not assess some of the factors that have been hypothesized by other researchers to be associated with hypertension among people actively on ART.RecommendationsThis research project identified the prevalence of hypertension among the patients related to certain covariates such as age, duration on ART, and BMI; however, we could not analyze certain other variables due to the unavailability of the data. Hence, a further study would be required to look into these other variables to ensure a holistic approach to the management of risk factors for hypertension in HIV care. More studies involving the analysis and measurement of the incidence of hypertension are required as these will aid with meaningful policy analysis and review.There is a need for data quality standard operating procedures to ensure that all critical variables that affect the quality of care in HIV clients are captured and accounted for. This should be followed up by the set-up of data quality indicators to monitor the data-capturing process. HIV care in Zimbabwe includes a feedback loop with the clients themselves that assesses the care that they are receiving; based on this data, while the researcher thinks that even though clients have rights and that they should advocate for improved care, they are simply unaware that they need to have NCD checks regularly as they also affect their quality of life ,18. A siPublic health implications of the studyThe findings from this study can be used to improve the management of HIV-related NCDs in Zimbabwe and throughout the sub-Saharan Africa region, which bears the major brunt of the HIV pandemic ,3,16. PaThe study demonstrated that there is a significant prevalence of hypertension in HIV-positive patients on ART and factors of age and obesity are independent risk factors along with the duration of ART. The secondary data analysis showed that there are gaps in the data collected by the facilities and could have hindered the assessment of overall prevalence rates; however, the study did present important outcomes while also highlighting that more needs to be done on data quality management as well as on improving the quality of HIV care as data on some important variables are not being collected. Lifestyle interventions to manage NCD prevalence need to be supported with the provision of resources as they are critical for the improved care of HIV patients.


The field of submicrometer polymeric production currently has a predominant research focus on morphology and application. In comparison, the sustainability of the manufacture of submicrometer polymeric fibers, specifically the energy efficiency, is less explored. The principles of Green Chemistry and Green Engineering outline frameworks for the manufacture of “greener” products, where the most significant principles in the two frameworks are shown to be centered on energy efficiency, material wastage, and the use of non‐hazardous materials. This study examines the power consumption during the production of Polyethylene oxide (PEO) and Polyvinylpyrrolidone (PVP) submicrometer fibers under magnitudes of the key forming parameters to generate fibers via pressure spinning. The energy consumption, along with the fiber diameter, and production rate during the manufacture of fibers is predominantly attributed to the characteristics of polymeric solutions utilized. Polymeric fibers are key engineering materials, however, they present environmental challenges. The study investigates sustainable production using Polyethylene oxide (PEO) and Polyvinylpyrrolidone (PVP), emphasizing green engineering principles. PVP exhibited better energy efficiency and higher production rates, however PEO generated smaller diameter fibers, with optimal control achieved at 35% concentration and 0.2 MPa pressure for both polymers produced via pressurized gyration. There have been several attempts to enhance the sustainability of polymeric fibers, such as the use of natural polymers and biodegradable polymers to minimize environmental impact. However, these do not usually account for potential environmental effects during the manufacturing stage of polymeric submicrometer fibers. The subject of sustainability has advanced to a stage where virtually every field of manufacturing has sustainability initiatives. Sustainability is also seen as a business approach, which enhances value for an organization whilst improving its environmental impact, along with the public and economy. Businesses have also increasingly acknowledged the merit of sustainability, such as in elevated publicity along with reduced manufacturing cost, energy, hazards, and risk. This can also be reflected in the field of biomaterials and industries that make use of submicrometer polymeric fibers such as the healthcare sector. There is a strong focus on the use of more sustainable materials in the production of polymeric submicrometer fibers, such as the use of biomaterials and non‐hazardous solvents. However, there seems to be a lack of emphasis on sustainability during the actual manufacture of submicrometer polymeric fibers.Polymeric fibers are used in many applications, for instance, in increasing quantities in the biomedical industry due to their resemblance with the extracellular matrix and along with their versatility.1 Meth In the case of polymeric nanofiber manufacture, the energy efficiency and safety factor are generally less discussed. Methods such as phase separation and self‐assembly can be inefficient in terms of energy consumption, whilst there are safety concerns such as the use of large voltages in electrospinning. In comparison, pressurized gyration is an energy‐efficient and safer process of producing polymeric fibers. This is due to its simplicity and production efficiency in comparison to some of the other popular polymeric nanofiber production methods, such as phase separation and template synthesis. The application of sustainable manufacturing has the potential to amplify an already sustainable process to produce the “greenest” submicrometer polymeric fibers.Sustainable manufacturing is the making of products via economically sound methods which promote minimal environmental impacts, energy efficiency, and the use of natural resources. Sustainable manufacturing also increases employee, public, and product safety, which subsequently increases operational efficiency, brand/product reputation, and competitive advantage.6 In t As a developed and highly adaptable field, the polymer industry plays an important role, as polymers are ubiquitous in modern society. However, drawbacks such as the large‐scale use of petroleum‐based raw materials and vast quantities of reagents that are of environmental threat, along with the build‐up of polymeric matter in the environment, bestows engineers and researchers the liability to re‐evaluate the manufacture of polymers with regards to the 12 principles of Green Chemistry  and Polyvinylpyrrolidone (PVP) to produce fibers via pressurized gyration. Both PEO and PVP are polymers with very low toxicity in comparison to other synthetic polymers and water‐soluble which as a consequence compliments the principles of Green Chemistry. Natural polymers are more “greener” however, synthetic polymers are functionally superior to natural polymers. Therefore, PEO and PVP was selected as a middle ground for this study as the polymers are both functional and less hazardous. Polymeric fibers with smaller diameters are idealized in many applications as they allow for enhanced surface‐to‐volume ratio, low density, high porosity, and high flexibility. For instance, in filtration‐related applications a higher surface‐to‐volume ratio promotes particle capture of a smaller scale and hence increases filtration efficiency. The paper investigates the energy consumption during the production of submicrometer polymeric PEO and PVP polymeric fibers using pressure spinning, which is a leading contender in the quest for reducing environmental impact of polymer fiber manufacture. Process control parameters were varied and the resulting energy consumption along with other output properties are calculated. Statistical analysis was used to recognize the main factors that influence energy consumption. The necessity of a full life cycle analysis to achieve optimal sustainability is proposed.Green engineering involves the development, marketing, and utilization of methods and goods with the aim of decreasing pollution, fostering sustainability, and mitigating potential harm to human health and the environment, all while maintaining economic feasibility and effectiveness.10 The1.1 The simplest model of the pressurized gyration method used in this study has polymeric solution placed inside a rotating vessel before being spun at high speeds along with the application of pressure into the vessel if necessary. The centrifugal forces generated from the spinning of the vessel along with the additional pressure difference compels the solution to jet out through orifices in thin streams and the solvent to subsequently evaporate in the process leaving behind polymer fibers. The fibers are gathered in a collector around the vessel which is positioned at a selected distance from the wall of the vessel. A schematic of this method is shown in Figure The manufacturing process of pressurized gyration is predominantly undertaken at ambient temperatures. The method is less complex and more straightforward in comparison to many other submicrometer polymeric fiber‐manufacturing methods.13 The The correct magnitudes applied to each parameter determines if any fibers are formed along with the properties of the fibers generated. Understanding how the magnitudes affect fiber production in terms of green manufacturing can be crucial to produce the “greenest” product.Various process control parameters affect the overall result of the substance that is jetted out from the orifices of the vessel.14 TheChanges in parameters will affect the properties of fiber such as its diameter and morphology, along with other properties such as the internal structure of the fiber. At present, there has been a strong focus on research on these physical and chemical properties such as the diameter and morphology of submicrometer polymeric fibers along with their applications. However, the sustainability aspect such as the energy consumption to produce these fibers are less discussed. In the case of infusion‐based gyration methods, the infusion rate also plays a significant part in the characteristics of resulting fibers. This is also the case in pressurized melt gyration where the polymer is melted  and hence the temperature applied is another important parameter. Other parameters such as collector distance and environmental conditions dictate the properties of the fibers. For instance, relative humidity plays a major role in the making of fibers that use a water‐based solvent or a water‐soluble polymer due to the low vapor pressure of water. However, this along with temperature can be maintained. To understand this, a study was undertaken with a focus on how the variation of rotary speed, pressure, and concentration affects energy consumption, along with fiber diameter and production rate during the pressurized gyration process as portrayed in Figure Previous studies indicate that the rotation of the vessel, along with the pressure and concentration of the polymeric solution are the primary parameters that contribute to the forming of fibers in pressurized gyration.14 In 22.1Polyvinylpyrrolidone , and polyethylene oxide  were obtained from Sigma‐Aldrich  and used as received. The solvent used was distilled water.2.2Table PEO and PVP were dissolved separately in distilled water to produce polymer solutions of concentrations of 30, 35, 40, and 50 wt.%. Homogeneity was achieved by magnetically stirring all eight solutions for 24 h at the ambient temperature (°C) and relative humidity (%). The PEO‐H2O and PVP‐H2O solution viscosities used in this study were characterized using a calibrated Brookfield Viscosity‐meter where the results are displayed in 2.3Figure The pressurized gyration device shown in Figure The collector distance was set at 100 mm where the laser tachometer readings show that the vessel reached average rotatory speeds of 12 000, 11 400, and 10 900 RPM at applied pressures of 0, 0.1, and 0.2 MPa, respectively.The production rate of the resulting fibers were calculated by measuring the mass of the fibers produced using a very sensitive scale and evaluating the time the fibers took to spin by reviewing video footage. The fiber diameter was evaluated using a scanning electron microscope (SEM). The micrographs acquired via SEM imaging were analyzed using Image J software to obtain the average fiber diameter. Energy consumption was calculated using a power meter connected to the power socket which displays the power drawn by the motor when used. The time taken to spin the fibers along with the average power meter reading was used to estimate the energy consumption.3A notable change in the rotary speed of the vessel was not identified with the use of the different concentrations of PEO and PVP. On average, under the same effecting parameters , the power consumption was very similar, where an average reading of 31.5 W is shown at 0 MPa for each sample, which increased by 5 W to an average of 36.4 W when a pressure of 0.1 MPa is applied and an average of 37.8 W at an applied pressure of 0.2 MPa. However, the actual power readings for each sample is utilized in this study as shown in Table Under the same magnitudes of affecting parameters, the energy consumption to produce PVP fibers is shown to be lower than the energy consumption to produce PEO as shown in Table Figure Figure PEO fibers were shown to have a relatively smaller diameter in comparison to PVP fibers under the same magnitudes of the three effecting parameters taken into consideration in this study . For instance, at a concentration 40% under an applied pressure of 0.1 MPa, PEO fibers resulted in an average diameter of 0.631 µm, whereas PVP fibers resulted in an average diameter of 0.941 µm as depicted in The results in Table Figure −1 at 0.1 MPa pressure, while the PVP fibers had a production rate of 26.7 g hr−1 under the same conditions. This is attributed to the differences in the solution properties of the two polymers as seen in Table Figure Although the magnitudes of the power consumption were comparable at the same magnitudes of the effecting parameters, a notable difference in the total energy to produce both PVP and PEO fibers is comprehended Figure 9. The eFigure The increase of applied pressure from 0.1 to 0.2 MPa does not show a better performance in energy consumption to produce PEO and PVP fibers in comparison to an increase in applied pressure from 0 to 0.1 MPa. This is due to the result of an application of pressure of 0.2 MPa which did not show a perceptible improvement in the time taken to form fibers but increased the power consumption to an average of 37.4 W across all samples as seen in Table Overall, it can be established that to result in optimum efficiency to produce PVP and PEO fibers, utilizing a pressure magnitude of 0.1 MPa is ideal taking into consideration the magnitudes of affecting parameters used in this study. Optimum efficiency considers the highest production rate and lowest fiber diameter (depending on applications) using the lowest energy consumption.Figure  Furthermore, highly viscous solutions also require more power to overcome the increased resistance to flow through the spinning equipment.4Overall, the results show that PVP performed better than PEO in terms of energy efficiency and production rate under the same magnitudes of effecting parameters. However, PEO was superior in terms of obtaining lower fiber dimeters under the same magnitudes of effecting parameters. Hence, it is inconclusive if PEO or PVP is preferable over the other to produce fibers via pressurized gyration considering both efficiency and application.−1 less than highest production reached at a value of 13.98 g hr−1 at a concentration of 50% and applied pressure of 0.2 MPa. The energy consumption under for PEO 35% at an applied pressure of 0.2 MPa was calculated to be 1484 J which is less than the median value for energy to produce PEO fibers in this study. In the case of PVP fibers at an applied pressure of 0.2 MPa and concentration of 35%, the diameter of the fibers and the energy to produce them were only 50 nm and 9 J respectively, more than the value of the fiber produced at a concentration of 30% under 0.2 MPa. The production rate was calculated to be 22.05 g hr−1 was over the median value for PVP fibers.With respects to the resulting production rate, energy consumption and fiber diameter due to the range of magnitudes of the affecting parameters in this study, it can be judged that both PEO and PVP performed best under an applied pressure of 0.2 MPA at a concentration of 35%. PEO fibers produced under these magnitudes of the affecting parameters the fiber diameter were only 5 nm larger from value of the smallest PEO fiber diameters produced in this study, whereas the production rate was only 1.5 g hr There has been a focus on how various rotational speeds affect fibers when using pressurized gyration, where higher speeds are associated with lower diameters of fibers which are idealized for many applications due to the resulting higher surface area to volume ratio. High rotational speeds supplemented with high applied pressure aid the extrusion process of fibers by producing higher centrifugal force along with force due to applied pressure to obtain diameters in the nanoscale. However, higher speeds may not be as energy efficient, due to the requirements of motors to draw in larger currents to reach such speeds and hence larger output power magnitudes. In comparison, this study shows that increasing the pressure does not drastically increase the power consumption of the motor. However, it was also summarized that increasing the pressure from 0.1 to 0.2 MPa did not result in a significant decrease in fiber diameter and increase in production rate, in comparison to increasing the pressure from 0 to 0.1 MPa. Regardless, the effects of higher magnitudes of applied pressure over 0.2 MPa can be explored and may be an effective approach to obtain fibers of lower diameters and higher production rates more energy efficiently.It has been concluded in previous literature that the rotary speed of the gyrating vessel along with the applied pressure are the primary parameters that dictate the morphology such as the fiber diameter of resulting fibers in the pressurized gyration method.14 The However, this study used water which is considered the “greenest” solvent. The surface tension of water is ≈72.8 mN m−1at room temperature which is high in comparison to other commonly used solvents such as acetone which has a surface tension of 24.5 mN m−1. Hence, the effects of applied gas pressure magnitudes and the rapid loss of solvents when using water as the solvent is comparatively insignificant.Furthermore, the results of this study proves that the viscosity of the polymeric solution is directly proportional to energy consumption to form fibers using the pressurized gyration method. Nevertheless, there is a need to also consider the surface tension of the solvent in the polymeric solution as gas pressure acting as the primary driving force can cause a rapid loss of solvent from the polymeric solution.19 How This can be further improved by adjusting the magnitude of infusion concerning parameters such as the rotational speed of the vessel and the concentration of polymeric solution utilized. Identifying exactly when a specific polymeric solution needs to be within the vessel once the motor has started  and having the polymeric solution enter the vessel at this precise time can ensure minimal wastage. It can also be estimated how long the motor is required to run for solutions to be infused into the vessel and converted into fibers. Using the volume of the solution along with the flow rate of infusion, the exact time the motor is required to stop to avoid unnecessary use of the motor (when there is no solution in the vessel) can conserve energy.During the study, it was observed that increasing the pressure immediately caused solution and polymers to spray out of the orifices rather than in fiber form, in comparison to applying pressure more gradually to the required magnitude once the rotary speed of the vessel is about to reach its critical speed for fiber formation. To abide by the principles of green engineering, more timed control of the application of pressure promotes less wastage of solution to optimize fiber yield as an immediate application of applied pressure causes the polymeric solution to spray or jet out of the orifices. Minimal wastage of polymeric solution subsequently increases the production rate of the system as the mass of fibers formed will be optimal. The experimental setup for pressurized gyration used in this research did not include infusion of the polymeric solution. However, infusion‐based gyration methods such as pressure coupled‐infusion gyration can promote less wastage, optimize production rates, and control fiber diameter.21 Thi When the motor is run under load, the power drawn will be higher than the rated power of the motor. However, lesser loads on the motor will show that the power drawn will be closer to the rated power of the motor.It is comprehended that the overall load on the motor dictates the power drawn by the motor. This is not only seen in the application of pressure but also when the motor is turned on when it is loaded with the vessel and when the motor is turned on when unloaded. The power drawn when the motor is turned when unloaded is equal to the power rating for the Nichibo motor used in this study, which is 21.2 W.22 Whe However, the plastic vessel cannot be used with solvents that may cause undesirable interactions with plastic surfaces. Carbon fiber can be a suitable material substitute as carbon fiber (in its rigid form) is usually used simultaneously with a polymer matrix to produce lightweight components. The epoxy resin used in carbon fiber makes the material chemically resistant to most alcohols, acids, and other chemical compounds. Along with this, the low thermal expansion of carbon fiber is ideal for vessels used in gyration‐based polymeric fiber manufacturing methods as they can withstand extreme heat.In general, metal vessels are popularly used for pressurized gyration systems. However, plastic vessels have also been used, where the plastic vessel has less load on the motor in comparison to the heavier metal vessel which therefore promotes better energy efficiency.23 How It is beneficial to visualize these principles as parameters where the application of one parameter may enhance one or more other principles of green engineering and/or green chemistry. Regardless, two of the most important concepts that designers are pushed to endeavor are considering the lifecycle and the first principle of green engineering, which promotes the minimal use of hazardous materials and energy obtained from hazardous means.It can be argued that the design of current submicrometer polymeric fiber manufacturing methods has been focused on quality and safety specifications. Consideration of green engineering principles and green chemistry principles in the design of polymeric fiber manufacturing methods can be utilized to enhance or consider environmental, social, and economic factors.10 It A life cycle analysis (LCA) is a method that can be used to evaluate environmental impacts such as energy consumption at all stages of polymeric fiber. The materials and energy inputs at every section of the life cycle of a specific product and process fully captures their life cycle. If a product is environmentally friendly but is made using hazardous or non‐renewable materials, the impacts are merely transferred to another part of the overall life cycle. Polymer and solvent selection are vital when considering the lifecycle. In the case of pressurized gyration, regardless of the method's energy efficiency in comparison to other processes, if the extraction and manufacture of certain polymers and solvents offset any energy savings, there is no net sustainable advantage. This study evaluated how the environmental impact can be improved in terms of energy used in the “manufacture” stage of the LCA of PEO and PVP polymeric nanofibers produced using pressurized gyration.Synthetic polymers are produced via polymerization, which is an exothermic process and is derived from fossil fuels. Therefore, it is useful to not only consider the functional and safety aspect of polymers but also the life cycle of the polymer material itself. Similarly, for the solvent used (distilled water), the distillation process of water requires the liquid to be heated until evaporation, along with nitrogen gas compression methods and energy to produce various concentrations of polymeric solutions can compromise overall energy efficiency. However, natural water is likely to suffice equally well in case commercial manufacturing is pursued. This study also proved that highly viscous polymeric solutions consumed more energy to produce polymeric fibers. This is also the case during the preparation of polymeric solutions of the same volume, where the high viscous solutions used in this study require more time to reach homogeneity on the magnetic stirrer. Hence, it is necessary to undertake a full life cycle analysis, including energy consumption during the application or use of polymeric fibers along with the distribution and end of life. However, the scope for this is too wide when considering the range of polymers, solvents, and the number of applications polymeric fibers are utilized for. An approach may be to identify the most popular application and most popular polymer used to produce fibers for this application and evaluate its life cycle considering the most efficient method of manufacture.5Based on the findings of this study, there were notable differences between the performance of PEO and PVP used in the pressurized gyration process. Overall, these differences highlight the importance of selecting the appropriate polymer for a given application in the pressurized gyration manufacturing. Both PVP and PEO performed best under an applied pressure magnitude of 0.2 MPa and a concentration of 35% and it is notable that these findings are in keeping with the magnitudes of the affecting parameters considered in this study.The choice of polymer can affect the production rate, fiber diameter, and energy consumption of the process, which can in turn impact the quality and cost of the final product. An increase in concentration or viscosity of PEO and PVP solutions subsequently increased the diameter of the fibers produced and production rate, along with an increase in total energy consumption to manufacture these fibers. An increase in applied pressure increased production rate and a decrease in fiber diameter. Improvements in the effects of the application of increasing pressure on energy consumption cannot be legitimately concluded for both PEO and PVP. However, energy consumption was seen to be lower with the application of 0.1 MPa of pressure, relative to no applied pressure. There may be potential for higher magnitudes of applied pressure over 0.2 MPa to improve energy consumption in the production of PEO and PVP fibers. Promoting energy efficiency was seen to be an important parameter in the principles of both Green Engineering and Green Chemistry. It is acknowledged that it is a significant challenge to incorporate all principles, however, practicing all 12 Green Chemistry and Green Engineering principles must become an aspiration for all polymer scientists and engineers. In this way, the inevitable and necessary transformation of polymer production toward a more sustainable future will be significantly supplemented.The authors declare no conflict of interest.


Isolated Patellar Aplasia Hypoplasia is a very rare autosomal dominant disorder. Its treatment depends on the clinical manifestations that can vary widely. The lack of active extension, which can be responsible for frequent falls due to a knee instability, is the most frequent and disabling manifestation. We report an original technique that is a modification of the Galeazzi technique for recurrent dislocation of the patella to gain active extension in case of PTLAH.A 7-year-old Caucasian boy with isolated Patellar Aplasia Hypoplasia and an extension lag of the right knee has been treated by a modified Galeazzi technique. The tendons of the semi-tendinous and gracilis muscles have been harvested and their distal insertion was kept intact. Both tendons were fixed over the top of the patella to restore knee active extension. After 6 years of follow up the patient is symptom free with a strong active extension of the operated knee.Reconstruction of isolated hypoplasia of the patella by a modified Galeazzi procedure is a safe and reliable technique for skeletally immature patients offering satisfying long-term outcomes. The Patellar Aplasia/hypoplasia (PTLAH) is a symptom present in several syndromes  like NaiWe report an original technique that is a modification of the Galeazzi technique  for recuA 7-year-old Caucasian boy was referred to our outpatient clinic for frequent falls due to both knees instability that was more pronounced in the right side. The family history revealed the presence of the same symptoms in his father.On examination, full range of motion of both knees was noted with an extension lag on active motion of 120° for the right side and 40° for the left side.The patella was not palpated into the patellofemoral groove with a protrusion of the femoral condyles. We could palpate a very small patella on the anterior aspect of the distal third of the thigh well above the patellofemoral groove. No palpable patella at all even on an ectopic position could be identified on the left knee. In both knees the patellar tendon could not be palpated. The patient was not able to hop on either leg. The rest of the clinical examination did not find any other orthopedic anomaly. The fingernails and toenails were normal. The psychomotor development of the child was normal.The patella was not visible on plain AP and lateral radiographs of both knees Fig. . Fig. 1AThe MRI found an ectopic small patella in the right knee but no patella on the left side. The radiographs of the child’s father who was 40 years old showed a bilateral small laterally dislocated patella Fig. .Fig. 2APRegarding the importance of the gait instability, it has been decided to surgically reconstruct the extensor mechanism of the right knee to regain active extension.The surgery was performed with the child in the supine position under a tourniquet hemostasis. With a small oblique incision on the medial aspect of the proximal tibia, we were able to identified the tendons of the semi-tendinous and gracilis muscles. With a tendon stripper we harvested both tendons at the musculotendinous junction and kept their tibial insertion intact.We then performed an anterior approach of the knee starting from above the small patella in the distal thigh, extending distally to the patellofemoral groove. The patella appeared small and the vestigial patellar tendon consisted of fibrotic bundle. The semi-tendinous and gracilis tendons were subcutaneously tunneled form their tibial insertion Fig.  exited tAfter closing the two wounds the knee was immobilized in extension with an above the knee cast for a 6 weeks period. After removal of the cast, the child was allowed to weight-bear and a passive and active physiotherapy performed with full flexion reached over a period of three months. At 6 years follow up, the child is reporting an improvement of the gait with a complete resolution of the right knee instability. On clinical examination, active range of motion was satisfying despite a persistent extension lag of 15° in the right knee Fig.  and stanThe clinical manifestations of the isolated PTLAH are very variable ranging from no complaint at all to flexion contractures of the knees in the neonatal period that impair the standing and walking ability of the patients . In mostThe goal of the treatment in our patient was to obtain a strong active extension of the right knee by reconstructing the patellar tendon which was found to be replaced by a loose fibrous streak. Several different tendinous transfers have been described in the literature, the most common one being the semi-tendinous transfer –7. We chReconstruction of isolated hypoplasia of the patella by a modified Galeazzi procedure is a safe and reliable technique for skeletally immature patients offering satisfying long-term outcomes.


In a natural acoustic environment, a preceding sound can suppress the perception of a succeeding sound which can lead to auditory phenomena such as forward masking and the precedence effect. The degree of suppression is dependent on the relationship between the sounds in sound quality, timing, and location. Correlates of such phenomena exist in sound-elicited activities of neurons in hearing-related brain structures. The present study recorded responses to pairs of leading-trailing sounds from ensembles of neurons in the rat’s inferior colliculus. Results indicated that a leading sound produced a suppressive aftereffect on the response to a trailing sound when the two sounds were colocalized at the ear contralateral to the site of recording . The degree of suppression was reduced when the time gap between the two sounds was increased or when the leading sound was relocated to an azimuth at or close to the ipsilateral ear. Local blockage of the type-A γ-aminobutyric acid receptor partially reduced the suppressive aftereffect when a leading sound was at the contralateral ear but not at the ipsilateral ear. Local blockage of the glycine receptor partially reduced the suppressive aftereffect regardless of the location of the leading sound. Results suggest that a sound-elicited suppressive aftereffect in the inferior colliculus is partly dependent on local interaction between excitatory and inhibitory inputs which likely involves those from brainstem structures such as the superior paraolivary nucleus. These results are important for understanding neural mechanisms underlying hearing in a multiple-sound environment. A natural acoustic environment typically contains multiple qualitatively different sounds that are generated at different time and locations. The perception of one sound can be affected by another sound, with the effect being dependent on the temporal and spatial relationships as well as the qualitative difference between the sounds . For insResponses to multiple sounds have been recorded in brain structures to study neural bases of auditory perception in a natural acoustic environment. In the inferior colliculus , neurons display two-tone suppression when two tone bursts are simultaneously presented . Action-The strength of the sound-driven response of an auditory neuron is dependent on excitatory/inhibitory inputs received by the neuron. For most IC neurons, major excitatory inputs are from the contralateral cochlear nucleus and lateral superior olivary nucleus (LSO), and the ipsilateral medial superior olivary nucleus . Major iThe dependence of sound-driven responses of IC neurons on excitatory/inhibitory inputs is supported by neurophysiological results . CharactA and glycine receptors in the IC to study how local inhibition contributed to the suppressive aftereffect.In the present study, we used a pair of leading and trailing sounds to elicit local-field potentials (LFPs) in the IC. We studied how the suppressive aftereffect produced by a leading sound was dependent on the temporal and spatial separations between the two sounds. We used pharmacological agents to block GABARattus norvegicus) were obtained from Charles River Canada Inc. . They were 210–600 g when experiments were conducted. Surgical anesthesia was induced by ketamine hydrochloride  and xylazine hydrochloride  and maintained by ketamine hydrochloride  and xylazine hydrochloride .Eighteen adult male Wistar albino rats . The rat, along with the head-holding and electrode positioning instruments, was placed in a Model CL-15A LP acoustic chamber  when sound-driven responses were recorded. Instruments were positioned in such a way that acoustic shadows and reflections were minimized. All procedures were approved by the University of Windsor Animal Care Committee in accordance with the guidelines of the Canadian Council on Animal Care.Sound waveforms were generated using a System 3 real-time signal processing system controlled by a personal computer running the OpenEx software . Sounds were presented using two FF1 free-field speakers  that could be positioned at any azimuthal location that was 50 cm away from the midpoint of the interaural line of a rat. Each speaker was calibrated over the range between 100 and 40,000 Hz using a model 2608 measuring amplifier and a model 4135 microphone . The microphone was positioned at the location where the midpoint of the interaural line would be. Calibration was conducted with the speaker at each of the five locations used in the present study, which included the midline of the frontal field and 90° and 45° on the contra- and ipsilateral side of the recording site . The central barrel was filled with physiological saline for the balance of electrical current.A “piggy-back” multi-barrel electrode assembly was used to record an LFP from an ensemble of neurons in the IC and to release neuropharmacological agents at the site of recording . The eleSignals registered by the recording pipette were amplified by 1,000 times and bandpass filtered (0.3–300 Hz) by a model 2,400A preamplifier . The signals were sampled at 3.1 kHz using the System 3 real-time signal processing system. The five barrels of the drug-release electrode were connected to a BH-2 Neurophore microiontophoretic system . To prevent drug leakage, a current around −20 nA was applied to each of the side barrels when a pharmacological agent was not being released.An electrode assembly was inserted into the right IC while Gaussian noise bursts at 60 dB SPL were presented from a loudspeaker at c90° to search for a site of recording. Recordings were conducted only on one side of the IC to minimize the utilization of electrode holding devices and avoid repositioning of holding devices, which helped maintain the consistency of an acoustic field. Upon identification of a recording site, the CF and the threshold at CF were determined for the site using tone bursts presented at c90°. These tone bursts had an 8-ms duration .L and TH. The frequencies of TL and TH were fL (lower than CF) and fH (higher than CF) and were calculated based on the CF of the recording site. The center frequency of fL and fH  was at CF while the frequency difference between fL and fH was 10% of the center frequency . A trailing sound was a tone burst with a frequency at the CF of the recording site. The leading and trailing sounds had the same intensity, which was typically 30 dB above the threshold at CF. The interval between onsets of the two sounds  could be varied systematically. Each train had 60 pairs of leading-trailing tone bursts. The interval between the offset of a trailing sound of one pair and the onset of a leading sound of a subsequent pair was 1,500 ms.A train of leading-trailing tone-burst pairs see  was creaResponses to a train of leading-trailing sound pairs were first recorded when the two sounds were colocalized at c90°  at the recording site to study whether/how the suppressive effect generated by a leading sound was dependent on local inhibition in the IC. The effect of a pharmacological agent was monitored by repeatedly recording responses to a leading and/or a trailing sound presented individually at c90°. For this purpose, a tone burst was presented at multiple  intensities ranging from slightly below the threshold at the CF to well above the threshold (including the intensity used for creating a sound pair). At each intensity a tone burst was presented 20 times; and all presentations  had a random order. The rate of sound presentation was 1/sec. Responses elicited at different intensities were used to create an amplitude-intensity function  and a latency-intensity function. When the effect of a drug on responses to individual sounds reached a stabilized level, responses to a train of sound pairs were recorded at various ISIs and angles of separation. AIFs for responses to the leading and the trailing sounds were also recorded. Following the evaluation of the effect of a drug, the injection current was terminated and a retention current was reapplied. Recovery was monitored by repeatedly recording responses to a leading or a trailing sound presented individually at c90°.Recording electrode and procedures”) were averaged separately to obtain mean waveforms for LFPs elicited at these intensities, respectively. In agreement with our previous result  in a sound pair was affected by the other sound in the pair and how the response was dependent on the spatial location of a leading sound as well as the temporal separation between leading and trailing sounds. An index of the normalized amplitude of response (NAR) was calculated for these purposes:paired  is the amplitude of the response to the sound under evaluation obtained when the sound was presented in a sound pair, with the leading and trailing sounds being at azimuth θ and c90°, respectively, and the interval between the two sounds being at Δt. Aalone (c90°) is the amplitude of the response to the sound under evaluation obtained when the sound was presented alone at c90°. A NAR value of 0 indicates that the response to a sound was completely suppressed in comparison to the response to the same sound presented alone at c90°, while a NAR value of 1 indicates that the response to a sound was not affected.Where AData analysis”). AIFs obtained before and during the application of the drug were compared. When a change in AIF produced by a drug stabilized, NAR values were calculated for responses elicited by leading and trailing sounds in a sound pair at each combination of temporal and angular separations. NAR values for responses to a trailing sound obtained before and during drug application were compared to find how the drug influenced a suppressive aftereffect.To determine whether a pharmacological agent affected local inhibition at the site of recording, an AIF was created using amplitudes of responses elicited by a single sound presented at a single azimuth but various intensities  software .L presented as a leading sound in one group (n = 9) while TH presented as a leading sound in another group (n = 9). Data obtained from the two groups were not different from each other (not shown). Thus, the data are combined in this article.LFPs elicited by single tone bursts and pairs of leading-trailing tone bursts were recorded in the right IC in each of the 18 rats used in the present study. The rats formed two groups, with TF = 0.410, p = 0.894 for amplitude, and F = 0.111, p = 0.998 for latency, respectively). Thus, over a train of leading-trailing sound pairs the response to a leading sound was not affected by preceding presentations of a trailing sound.Shown in 0.7, was used in the article to reflect the duration of suppression. When the ISI was 264 ms, the response to a trailing sound was almost identical to that elicited by the sound presented alone. The latency of the response to a trailing sound was not affected by a leading sound at any ISIs .The response to a trailing tone burst at c90° was greatly suppressed by a colocalized leading tone burst when the two sounds were separated by a small ISI . The Tukey’s test revealed that the NAR value for the response to a leading sound was significantly reduced when the sound was relocated from c90° to i45° (p = 0.001) or i90° (p < 0.001). The same test revealed that the NAR value for the response to a trailing sound was significantly increased when the leading sound was relocated from c90° to i90° (p = 0.021). Latencies of responses to leading and trailing sounds were not changed by the relocation of a leading sound . A post-hoc t-test indicated that the difference was significant at all ISIs between 12 and 72 ms . The latency of the response to a trailing sound was not affected by the ISI and the location of a leading sound .Time courses of suppression produced by a leading sound at c90° and i90° were compared in each animal. Shown in Gabazine released at the site of recording enhanced both LFPs elicited by a leading and a trailing sound when they were presented in a pair . It alson = 8) support that gabazine changed the degree of suppression when a leading sound was at c90° . A post-hoc t-test indicated that the reduction was significant at the level of p < 0.1 when the ISI was at 40 ms (p = 0.063). An increase of NAR value at short ISIs was accompanied by a decrease of ISI0.7 value at a statistical significance level at p < 0.1 . When a leading sound was at i90°, gabazine did not change the degree of suppression . It did not change the ISI70, either .Group results (Strychnine increased amplitudes of both responses to a leading and a trailing sound no matter whether the sounds were presented in a pair  or indivn = 7) indicate that strychnine reduced the degree of suppression generated by a leading sound when the sound was at c90°  and when it was at i90° . A significant drug-induced change was observed at all ISIs between 16 and 264 ms when a leading sound was at c90° and at ISIs at 24 and 40 ms when a leading sound was at i90°  and i90° .Group results , both ears are stimulated which leads to the activation of neurons in all structures that provide inputs to the IC. These source structures include those driven by the contralateral ear only and those driven by both ears . When a The time course of a suppressive aftereffect may also be dependent on the type of neurophysiological signal that is used to reflect the aftereffect. In the present study, LFPs generated by a population of neurons rather than action potential discharges generated by single neurons were registered. It is generally believed that the generation of an LFP depends on current dipoles produced nearby a recording electrode, which primarily reflect postsynaptic potentials created by neurons . It is cAmong the major findings of the present study was the directional dependence of the suppressive aftereffect generated by a sound. Such an effect was the strongest when a sound was presented at the ear contralateral to the IC –6. This The peak latency of an LFP elicited by a trailing sound was not substantially affected by the temporal and spatial relationship between a leading and a trailing sound. This might be because the latency was primarily dependent on the excitatory inputs that drove the LFP response  . LatenciLocal application of Gabazine or strychnine reduced the suppressive aftereffect produced by a leading sound –10. DuriGABAergic innervations received by the IC include those from the ipsilateral SPN, which is driven by excitatory inputs from the contralateral cochlear nucleus . This paA receptors (Major glycinergic inputs to the IC are from the ipsilateral LSO and VNLL . Neuronseceptors . If theseceptors , 10 likeThe effect of a pharmacological agent on an LFP is dependent on both the area over which the agent spreads and the area within which neurons contribute to the LFP. Currently, there are no effective methods that can be used to evaluate the sizes of these areas. Some existing results from the IC suggest that a drug released microiontophoretically can reach neurons that are a few hundred micrometers away . Thus, iPrevious findings indicate that a sound can produce suppressive aftereffects in lower auditory brain structures including the 8th nerve fibers and brainstem nuclei . Such efA and glycine receptors on the suppressive effect indicates that local inhibitory neurotransmission contributes to the suppressive aftereffect displayed by neural responses in the IC. It implies that such neurotransmission contributes to behavioral/psychoacoustic phenomena of forward masking and the precedence effect.Previous studies based on activities of individual neurons have suggested that a sound-elicited suppressive aftereffect in the IC is involved in generating hearing phenomena such as forward masking  and the A sound-elicited suppressive aftereffect may also contribute to other aspects of spatial hearing. To understand how the detection of a recurring sound is affected by another independently recurring sound, we previously used two tone bursts to create a train of stimuli with a random order , 2020. SIn general, a sound-elicited suppressive aftereffect on neural responses in the IC is important for hearing in a natural acoustic environment in which qualitatively different sounds occurs at different time and locations. Local neural mechanisms including excitatory/inhibitory interactions contribute to the generation of such an aftereffect.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.This animal study was reviewed and approved by University of Windsor Animal Care Committee.HZ conceived and designed the experiments. SA, ST, NR, and OS performed the experiments. SA and HZ analyzed the data and contributed to the writing of the manuscript. All authors contributed to the article and approved the submitted version.


The capital shortage for marine ranch construction will reduce their economic, ecological, and social benefits. By constructing the supply chain decision model to solve and analyze the results, we found that the change of the products’ environmental friendliness and the environmental enrichment degree of the marine ranching companies will affect the marine ranching construction level, and they are positively correlated. In addition, the enhancement of the guiding effect of government guidance fund can break through the dilemma of enterprise capital shortage and optimize the establishment and development level of marine ranching.The construction of marine ranching is a concrete practice to fulfil the strategic objective of China’s maritime power. The shortage of funds has turned into an important issue to be resolved urgently in the modernization of marine ranching. This study constructs a supply chain system, involving a leading enterprise of marine ranching with short funds and a retailer, and introduces the government guidance fund to solve the issue of capital shortage. Then, we discuss the supply chain financing decision under two different power structure modes, and analyze the product environmental attribute  and the guiding effect of government investment on the operation of different modes. The research shows that: (1) The wholesale price of products is mainly influenced by the dominant position of the marine ranching leading enterprise. Furthermore, the wholesale price and the marine ranching company’s profits increase with the growth of the product environmental attribute. (2) The retailer’s profit and the supply chain system’s profit are mainly affected by the dominant power of the retailer and are positively correlated with the product environmental attribute. In addition, the supply chain system’s overall profits are negatively related to the guiding effect of government investment.  The waste of ocean resources and the disruption of the ocean environment make traditional fisheries face the dual constraints of resources and environment . Marine In view of the fund shortage for marine ranching establishment, the leading enterprises can adopt a variety of ways and channels to grow capitals. Enterprises can adopt supply chain finance (SCF) to ease the fund shortage. In the past few years, academic circles have paid more attention to SCF ,6 and SCThere can be many diverse structures in the supply chain model. For the study of different power structures in a supply chain, scholars have conducted extensive discussions. For example, Luo et al.  construc(i).The government guidance fund is applied to the marine ranching to study the influence of different power structures on supply chain operation. It broadens the research boundary of the government guidance fund.(ii).Environmental enrichment and product’s environmental friendliness constitute the product environmental attribute of the marine ranching leading enterprise. The impact of this variable on the operation of the supply chain is analyzed.(iii).Through parameter sensitivity analysis and comparative analysis of the two modes, relevant management suggestions are put forward from the perspective of the marine ranching leading company and the retailer, respectively.According to the above analysis, the contribution of this paper can be divided into the following three points:This part expounds four kinds of literature flows based on the research themes and objectives: (1) marine ranching, (2) government guidance fund, (3) supply chain financing decision, and (4) environmental enrichment.The notion of marine ranching comes from the practical experience of the scientific utilization of the ocean, and has steadily improved with the growth of fisheries. Marine ranching was first proposed by Japanese scholars in 1971, and it was defined as a system that can continuously produce food from marine biological resources. In 1979, Zeng Chengkui put forward “marine farming, marine pasture”, from which the notion of marine ranching in China originated . The 230The problem of fund shortages in marine ranching leading enterprises has many ways and channels to solve. SCF and other financing methods can raise more funds for enterprises . The SCFThere are two ways for the government to ease the dilemma of company capital shortage: direct government subsidy and a government guidance fund . On the SCF is an effective way for companies to obtain operating capital by using supply chain cooperation relationships . How decEnvironmental enrichment, which refers to a method of improving animal welfare and biological functions through a deliberate increase in environmental heterogeneity and complexity , has shoIn summary, based on the existing literature, this study introduced the government guidance fund to deal with the financing problem of marine ranching. Then, the effect of diverse power structures on supply chain operation were studied, which broadens the research boundary of the government guidance fund. In addition, the environmental enrichment variable is introduced into the study of the model to discuss the effect of this variable on the optimal decision results. Finally, the corresponding management enlightenment is put forward from the view of leading enterprises in marine ranching and retailers.The construction of marine ranching can not only develop and utilize marine biological resources reasonably and effectively, but also bring great social, economic, and ecological value. However, the marine ranching leading enterprises will face the shortage of funds in the progress of management and growth. As start-ups, the shortage of funds limits the operation and scale expansion of leading enterprises in marine ranching. The government, as a promoter of economic development, can take shares in marine ranching through government guidance funds, alleviate the constraints of the enterprise capital shortage, and then promote the continuous growth of marine ranching. Meanwhile, the government also promotes social capital into the marine ranching through its guiding effect, and then jointly solves the capital shortages of leading enterprises in marine ranching. Based on the description of the problem, this study constructs a supply chain system including a leading enterprise in marine ranching and a retailer. After the production process of the leading enterprise is completed, the enterprise sells the products related to marine living resources such as fish, shrimp, and shellfish to the retailer at a wholesale price According to the difference of dominant power between the leading enterprise and the retailer in the supply chain system, two different modes are formed. In the two modes, there is a game relationship between the two sides. In the process of game, both sides constantly adjust their own strategies to seek optimal decisions. To facilitate analysis, the following hypothesis are put forward.Hypothesis 1.The private capital of the leading enterprise in marine ranching is , the government investment is , and the initial investment of social capital is . Considering the guiding role of government investment, the final investment of social capital is , where is the guiding role of government investment. Considering that the government can drive social capital into the marine ranching leading enterprises through its guiding effect, the guiding role of government investment should meet Hypothesis 2.The product demand of the leading enterprise in marine ranching is , in which the market capacity is , is product price, and , are both >0. is the product price coefficient, and ; is the product environmental attribute, which are influenced by the product’s environmental friendliness  and the  ; is the influence coefficient of the product environmental attribute on demand, ; when the product’s environmental friendliness and the marine ranching enterprise’s environmental enrichment are improved, consumers will increase their purchase of the product. Considering the product demand should be greater than 0, so the product demand should meet Hypothesis 3.The production cost per unit product of the leading enterprise in marine ranching is , the financing cost is , and , Hypothesis 4.The proportion of government-owned marine ranching leading enterprise is , the proportion of social capital-owned marine ranching leading enterprise is , and the private capital ratio of the marine ranching leading enterprise is ,62. Ther , . Where represents the maximum proportion of equity that two entities can have. In order to ensure that both parties do not lose their control rights, it is necessary to meet the condition , namely , Hypothesis 5.The marine ranching company and the retailer are both risk-neutral. They all make their own deci-sions with the aim of maximizing their own benefits.Then, for the convenience of analysis, all the notations and the definition of the corresponding notations are listed in According to the above hypotheses, the profit of the leading enterprise and the retailer can be expressed, respectively:The profit of the supply chain system can be expressed as:In the Stackelberg game model, the latter player can choose his own strategy according to the strategy of the first player, and the latter player’s strategy will also respond to the first player . In the The backward induction is a method to solve the dynamic game equilibrium, which means that the actions of the participants in the game have a sequence, and the latter party can observe the actions of the former . BecauseIn this mode, the leading company of marine ranching occupies a dominant position. Then, the marine ranching leading enterprise first decides the product wholesale price Based on the backward induction method, the optimal decision-making problem of the marine ranching leading company and the retailer under this mode is solved. From Equation (1) and Similarly, the profit of the retailer can be expressed as:From Equation (5), the first and the second partial derivative of Substitute Equation (6) into By substituting Equation (6) into Equation (4), the profit function of the leading enterprise in marine ranching is:From Equation (8), first order partial derivative and second order partial derivative of Substituting Equation (9) into Equation (7), the optimal of product’s retail price can be obtained:Substituting Equation (10) into Equations (9) and (10) are substituted into Equations (4) and (5), respectively, to solve the optimal profits of the leading company and the retailer.In this mode, the sales dominance is in the hands of the retailer, who occupies a dominant position in the supply chain system. The retailer’s position is higher than that of the marine ranching leading enterprise, and it occupyies a dominant position in the supply chain system. Meanwhile, the retailer first decides the product’s retail price Then, the optimal decisions of the leading enterprise and the retailer under this mode are solved by the backward induction method. For simplicity of calculation, we assume that the expected return of the retailer is By substituting the Equation (12) into the Equations (4) and (5), the profit of the leading enterprise and the retailer can be expressed, respectively:According to Equation (13), the first order partial derivative and the second order partial derivative of Substituting Equation (15) into Equation (14), we can obtain:Based on Equation (16), the first order partial derivative and the second order partial derivative of Substituting Equation (17) into Equation (15), the optimal wholesale price of product is:Substituting Equations (17) and (19) into Equation (12), the optimal retail price of product is:Substituting Equation (19) into Equations (17) and (18) are substituted into Equations (13) and (14), respectively, to solve the optimal profits of the leading company and the retailer.According to Conclusion 1.In the mode dominated by the marine ranching leading company:The optimal product demand is The optimal retail price of the product is The optimal wholesale price of the product is The optimal profits of the retailer is The optimal profits of the leading enterprise in marine ranching is The overall optimal profits of the supply chain system is Conclusion 2.In the mode dominated by the retailer:The optimal product demand is The optimal retail price of the product is The optimal wholesale price of the product is The optimal profits of the retailer is The optimal profits of the leading enterprise in marine ranching is The overall optimal profits of the supply chain system is In order to facilitate the comparative analysis of diverse dominant modes, we list the equilibrium results for the two dominant modes in This part compares and analyzes the optimal solutions of the two modes (Conclusion 1 and Conclusion 2) in the supply chain system, and draws Conclusions 3–8.Conclusion 3.In the two modes, the wholesale price of product has a relationship of ; , increase with the growth of Proof. From In addition, the first partial derivatives of As seen in Conclusion 3, the products’ wholesale price is mainly influenced by the dominant position of the marine ranching leading company in the supply chain system.By comparing the mode dominated by the leading enterprise and the mode dominated by the retailer, we can see that when the leading enterprise dominates the supply chain system, to effectively guarantee its own profits maximization, the wholesale price set in the decision-making is higher. Under the retailer-led model, the retailer makes its own best decisions to make the profits optimal, which will decrease the product’s wholesale price as a retailer’s cost.Under the two modes, with the growth of the product environmental attribute, the marine ranching leading company will increase wholesale price accordingly. This is because with the growth of Conclusion 4.In the two modes, the retail price of product has a relationship of ; , increase with the growth of Proof. From Equations (10) and (19), we can obtain:In addition, the first partial derivatives of From Conclusion 4, it can be concluded that the retail price of products has nothing to do with the dominant position of all participants in different supply chain modes. Under the mode dominated by the marine ranching leading company and the mode dominated by the retailer, the retail price of products set by the retailer is the same. This indicates that regardless of the retailer’s position in the supply chain system, it will not affect the product retail price. In these two modes, the price formulated by the retailer is related to Conclusion 5.In the two modes, product demand has a relationship of ; , increase with the growth of Proof. From Equations (11) and (20), we can obtain:In addition, the first partial derivatives of As with Conclusion 4, the product demand has nothing to do with the dominant position of all participants in diverse supply chain modes.As shown in the two different modes, no matter which subject is dominant in the supply chain system, the product demand in optimal decision-making is always the same. This is because, in these two modes, the retail price of the product remains consistent  As far as the marine ranching leading companies are concerned, the wholesale price is mainly impacted by the dominance of the marine ranching leading company in the supply chain system. Generally speaking, there is a positive correlation between wholesale price and its dominant position. The products’ wholesale price is higher in the mode dominated by the marine ranching enterprise and lower in the mode dominated by the retailer. In addition, the optimal profits of the leading company are also related to its dominant position, and they are positively correlated. The marine ranching leading enterprises’ profits show the same trend with the environmental attributes of their products and decreases with the growth in the guiding role of government investment.(2) For retailers, the products’ retail price is not significantly affected by the retailer’s dominant power. The product demand and the retail price are one-to-one correspondence in these two modes. The retail price is consistent in the two modes, and the demand also has an equal relationship in the two modes. The retailer’s optimal profits are positively related to its dominance in the supply chain system, which is higher in the mode dominated by the retailer and lower in the mode dominated by the marine ranching leading company. The product retail price, demand, and retailer’s profits will increase with the growth of the product environmental attribute. In addition, the overall profits of the supply chain system will also be affected by the retailer’s dominance. They are positively related to the environmental attribute of products and negatively related to the guiding role of government investment.According to the conclusions of the last section, this section puts forward corresponding management enlightenment from the perspective of the marine leading companies and retailers. First, on the one hand, the leading companies of marine ranching can effectively integrate the concept of environmental friendliness into the whole process of the product production line by using green environmental protection materials  and thenSecond, retailers, as the downstream enterprises of the supply chain system, can stimulate consumers’ demand for highly environmental friendliness marine-related products by designing efficient marketing strategies to encourage consumers to purchase. In addition, retailers can also carry out product brand publicity activities through a variety of channels to convey information on the environmental friendliness of marine products and their environmental enrichment to potential consumers, and to enhance the brand image of products, so that consumers have a sense of identity and belonging to such products, and then the retailer’s own profits reach a high level.Third, government, as a policy maker, can formulate relevant policies to enhance consumers’ awareness of purchasing environmental products. Moreover, the government can also establish an effective supervision mechanism and use public opinion to enhance consumers’ demand for environmental friendliness products produced by marine ranching leading enterprises, thereby enhancing the overall profit level of the leading enterprises, retailers, and supply chain systems. In addition, the government should effectively use the amplification effect of financial leverage and guide social capital to jointly invest in the start-up marine ranching leading companies so as to promote the operation of enterprises.This study discusses decision-making under different dominant modes, the action mechanism of product environmental attribute on the decision-making of the marine ranching leading company, and the guiding role of government investment in decision-making. The application of this model will help study the establishment and development of marine ranching from a multi-disciplinary perspective. However, this research can be further developed. Firstly, in this model, we only consider the influence of the product environmental attribute of the leading enterprise in marine ranching on the decision-making of the supply chain system. In the progress of actual management operations, in addition to the impact of the product environmental attribute on decision-making, other elements (such as advertising and public opinion) will also affect the decision-making system . Secondl