Introduction: Limited self-report data suggest that South Asian (SA) women fail to meet physical activity (PA) recommendations. Recent research using objective measures reveals SA women living in the UK have higher PA levels than previously reported, and a pattern of under-reporting PA and sedentary time (ST). There is limited research on SA women’s understanding and experiences of PA/ST, and the cultural contexts and conditions within which they occur. Therefore the aims of this mixed-methods study were to compare perceived PA and ST to objectively measured data and explore PA- and ST-specific contexts, experiences, and sources of PA and ST amongst SA women in the UK. Methods: 24 women were purposively sampled to participate in a semi-structured interview from a larger study of 140 women who wore an accelerometer for 7 days. Demographic and anthropometric data were also collected. Results: Notable qualitative themes on contextualisation were of adequate PA as “keeping busy” or “being healthy”, and of ST as “lazy” or “resting in old age”. Few participants reported being sedentary, and most believed they were sufficiently physically active. Objectively measured PA/ST indicated that 66% women were less active than perceived (with regard to duration and intensity), with none able to estimate duration of ST. Discussion: Findings suggest that overall, SA women have contextualisations of PA/ST that may not coincide with those of researchers, health professionals and policy makers, and lack awareness of the intensity of PA in which they engage and the health risks of high levels of ST. These findings highlight the need for objective measures of PA and ST in this population combined with in-depth qualitative assessments to provide more accurate assessments of these behaviours. This information can subsequently be used to develop health promotion messages and interventions focusing on increasing duration and/or intensity levels of daily activities  and reducing ST in this population. Physical activity (PA), defined as bodily movement that expends energy using the skeletal muscles , and sedA recent systematic review highlighted that 26 quantitative studies  and only 12 qualitative studies have been published to date investigating PA among SA women, with none investigating ST . This reDue to the limited evidence currently available about the levels, experiences and perceptions of PA and ST among SA women, the aim of this mixed-methods study was to use semi-structured interviews and accelerometry to: (1) compare perceived PA and ST to objectively measured data; and (2) explore PA- and ST-specific contexts, experiences, and preferred sources of PA and ST amongst SA women in the UK.The overarching framework guiding this research was an ecological model of PA and ST that recognises the determinants of PA and ST behaviours being a result of interactions between personal experiences, as well as the social and environmental contexts in which people live ,10. ThisParticipants in the current study were recruited from a larger study conducted in Cardiff, Wales, examining PA and ST among 140 SA women (Bangladeshi and Pakistani women) in the UK. from January 2012 to March 2013   were used to objectively measure PA and ST. Accelerometers are small, non-invasive devices that measure frequency, duration and intensity of bodily movement . A recenSemi-structured interviews were used to collect data on contextualisation, barriers, facilitators, and experiences of SA women’s PA and ST. The interview guide consisted of 15 questions, with additional probing questions. Questions on the contextualisation of PA and ST included: “What do you think it means to be physically active?” and “What do you think it means to be sedentary?” Women were asked if there were other terms they or others might use instead of “physically active” or “sedentary”. Other questions included those on anything happening at home, in the neighbourhood or community that make it easier or harder to be physically active, what a typical weekday and weekend day is like, and how they and their family/peers view PA/ST. They were asked to recount their daily weekday and weekend schedules. Additionally, questions on PA and ST participation were included, such as: “are you physically active and if so, what activities do you do and how often?” and “are you sedentary and if so, what do you do during those times and for how long?” The interview guide was in English but was orally translated as needed by trained community worker interpreters into Sylheti, Bangla, Urdu, or Punjabi. To verify accuracy of translation, interpreters back translated five interviews from recordings.Self-reported PA and ST levels were also assessed in the larger study with a sub-sample of 50 women using the short version of the International Physical Activity Questionnaire  13]. A. A13]. ADetails on accelerometer data collection and processing from the larger accelerometer study are reported elsewhere . BrieflyAccelerometer data were downloaded using Actilife 6 software  and data reduction conducted using Kinesoft software . In order to capture routine activity and variations in activity, three valid days (including at least one weekend day) were included for analysis. A valid day was defined as a minimum of 600 min of registered wear time. Non-wear time was defined as over 60 min of zero counts . Cut poin = 6) to check for agreement in coding. A final coding matrix was then developed and all data reviewed again and coded based on the final agreed categories and subcategories. Perceived PA and ST levels were estimated based on frequency, duration, intensity and mode of various activities reported during the semi-structured interviews.All audio recordings of interviews were transcribed verbatim for analysis by a researcher (WBC) and then checked for accuracy by a research assistant. Deductive content analysis  was used2, mean body fat percentage was 49.3 ± 17.7%, and mean waist circumference was 98.8 ± 13.0 cm. This sample engaged in an average of 553.2 ± 59.4 min of ST per day and 34.6 ± 21.5 of MVPA per day. When compared to the larger study sample of 140 women, those participating in interviews were, on average, 6 years older but similar in BMI, body fat percentage, waist circumference, and level of deprivation …things you can find to do…in the house. There’s always, you know, if it’s not washing, it’s ironing…”“Since few women were able to report their levels of ST during the week, a comparison of their description of activities done during ST was made between women who achieved the highest and lowest levels of objectively measured ST to identify any patterns. When comparing the participant who accumulated the highest ST with the participant who accumulated the least, differences in daily patterns emerged. Participant B had the highest levels of objectively measured ST in the sample. She accumulated less ST around what might be considered traditional times . This could be a time when she was cooking and therefore not sitting down to accumulate as much ST as other times during the day. Participant B says:…you know, you gotta face the evenings and that’s the worst part of it you know, sitting home and doing nothing.”“She also commented on being sedentary in the evenings:Evening times especially [I am sedentary]. Because I get up early [in] the morning and I’m tired by evening… [I] lie down on the sofa.”“Participant G had the lowest levels of objectively measured ST of the sample. Her levels of ST were lower in the morning from 7:00 to 9:00 and then still relatively low, compared to the total sample, from 12:00 to around 18:00. The interview with this participant revealed that she did housework in the mornings, looked after her 3-month-old granddaughter during the day, and by the evening she was able to sit and relax. After a long day of being busy she notes that:…Physically active to me means doing things. Being busy with life, housework, cooking, cleaning and going out and about.”“Often the terms PA and exercise are used interchangeably in the literature to indicate bodily movement above rest that results in energy expenditure . TherefoExercise probably means a bit more in depth, like doing a lot more…Whereas physical activities I just consider like, walking, you know.”“The majority of women (58%) responded that walking was a form of PA and that they did not need to go to the gym to keep active. Some women also responded that being physically active meant to do exercise. Examples of this were going to the gym, doing aerobics, and taking yoga. Women conceptualised the term “exercise” similarly to that of PA, and thus used the terms PA and exercise interchangeably. Many responses included references to walking and housework as PA. Most structured activities such as aerobics, yoga, swimming and going to the gym were repeatedly mentioned as activities that would be considered as exercise. Some women expressed the belief that exercise required “extra effort” and would be “harder” than PA. One Pakistani 52 year-old woman (P) explained:I think it’s good to be active. It’s good for your health. Um, otherwise you’ve got all these other illnesses that come along.” “Another major theme was the idea that PA equates to being healthy. Nearly all women (92%) indicated that being physically active meant being healthy. Particularly, they felt that being active helped keep illnesses away, helped with depression, can lead to weight loss, maintains healthy joints and helps with stress relief. A 39 year-old Pakistani woman (V), when asked what she thought it meant to be physically active, commented that:Good health. Good mind. Help stay away from illnesses.”“Similarly a 60 year-old Pakistani woman (L) responded that it meant:n = 9) of the sample was the idea that being physically active would help women maintain their independence as they age, and would allow them to be free from relying on others to take care of them by preventing ill health. One 46 year-old Bangladeshi woman (N) stated:…you know, it’s really important to keep yourself healthy because you’ve got to think as well…who’s going to look after you?”““Good health” was a common response when discussing concepts around PA, and there seemed to be an innate link between PA and health for them. Of particular importance for 38%  also commented on keeping her independence:Physically active means whatever you want to do, you are able to do it without ah, feeling you’re ah, you know, you’re in pain or anything like that.”“Remaining free from pain and stiffness was a major concern for the older women who were interviewed. They expressed concern that they would not be able to enjoy doing the things they wanted to without staying active. For example, a 58 year-old Pakistani woman (K) said:I have um, something…to do all the time. Either cleaning the house or like you know…Well in the evening I do take rest. I just um, I lay down and then I do nothing. But um, I think that I deserve [to rest] after the whole day.”“The concept of “being sedentary” was explored before asking participants how much ST they engaged in. Twenty-one women (87.5%) did not know what the word sedentary meant and required an explanation by the interviewer. Once defined (as spending free time sitting or laying down), participants expressed the concept of being sedentary as falling into two main categories. Firstly, it was seen as resting or “taking it easy.” Nearly all women who referred to being sedentary as resting commented on a sense of deserving a rest after a long and busy day. Many women wanted to relax after doing their housework. One 61 year-old Pakistani woman (R) said:…problem becomes when woman becomes mother-in-law and comes home and that’s it. It’s my time to sit now. She [daughter-in-law] will do everything. It’s her responsibility. I done my job. Even mother-in-law may still be in early forties. So that’s where the thing goes wrong. Personally that’s my view.”“Other women referred to being sedentary as being lazy. These women conceptualised being sedentary as not keeping busy, not keeping up with their housework and being a “lady of leisure.” Importantly, both younger and older women remarked that after a woman becomes a grandmother (around the age of 40 years), she becomes very sedentary and stop doing things for herself. This was reported as being a widespread phenomenon in the community. The daughter-in-law was identified as being primarily responsible for taking care of the older woman and what used to be her household duties. One older (60 year-old) Pakistani woman (L) commented:They [daughters-in-law] have to encourage their mother-in-law to do a little bit of housework. Um, I know like within Asian culture it’s rude to ask somebody to do that.”“One younger (36 year old) Bangladeshi woman (X) agreed, and expressed the difficulty in changing this cultural norm:n = 18) stated that being sedentary either exacerbated their current illnesses and injuries or could bring about new ones. Obesity, diabetes, depression, and limb pain were the most common conditions mentioned in interviews.Additionally, 75% of women (n = 18) said that they did so by doing housework throughout the day. This included tasks such as cooking, cleaning, vacuuming, and ironing. None reported a specific amount of time spent on housework, but broadly indicated that it was done throughout the day and in between prayer and meal times. Younger women who were not yet grandmothers reported that they were able to stay active because they were busy taking care of their children in addition to housework. One 38 year-old Bangladeshi woman (O) recounted her busy day:Ok. I wake up in the morning and get the kids ready, make their breakfasts. Um, then when I take them to school, come back home, clean the house, do the cooking. Um, after that you know, when the cooking is done, by that time the kids are home. I pick ‘em up. I drop them off. I pick them up. Getting them ready again to go to the mosque. Feeding them. And then when it’s evening time um, when they’re in the mosque, the little ones are there so I’m either doing ironing, or something, I’ll be doing. Just to get all the housework out of the way. And um, and when the kids come home, bedtime, getting them ready, bathing them and bedtime. And um, in the mornings, sorry sometimes when I don’t have housework and um, I don’t have um, what’s it called, um, cooking to do then I’ll do my business. Sit down and do some calls. So I am active every day. And when they go to bed I’m like too tired now and I want to go to bed (laughs).”“Twenty-one (87.5%) women reported being physically active. Of these women, 85.7%  of women reported being active through caring for another family member. This often included a mother-in-law, father-in-law, and/or grandchildren. One 52 year-old Pakistani woman (P) spoke about her many responsibilities:I’m a housewife. So [I’m] busy in the home. Because we are Asian, Pakistani. I have three sons grown up. And um, husband has not been very well. He was engineer but he can’t work because he’s so ill. Um, and I have a mother-in-law. Ya, she’s old. She’s over 70. My father-in-law passed away about seven years ago so then I look after my mother-in-law. And my children, my husband.”“Taking care of children was not the only source of activity for women; 29.2%  women reported that they currently walk for PA. As previously described, only three women were able to recall the length of time they walked. One woman reported walking for 15–20 min per day, one stated she walked for at least 45 min per day, and another stated she walked for 1 h per day. Four women reported that they were active when they went shopping during the day, but did not report the length of time or intensity for this activity or how many days per week they engaged in shopping. Three women cited group exercise classes as another way of staying active. These classes included Extend (seated or standing light exercise class), Zumba (or other dance class), and yoga. One 36 year-old Bangladeshi woman (S) recalled:None reported the duration of the classes, although based on observations of classes held in community centres in the area, these classes typically last for approximately 1 h. One woman stated that she took a class two days per week, while the others did not specify frequency. Three women recalled that they went to the gym to stay active, although none specified what types of activities they engaged in at the gym. One woman, the same woman who recalled two days of group classes, reported 1 day per week of going to the gym.…these days um, everybody, every community has their own channel [referring to South Asian TV channels in native languages]. Which means they are being lazy. Because um, there’s no um, language barrier and they just watch their language channels. They understand them. They enjoy it. So that means um, after lunch or after… they just sit there and…as a family and watch TV. Which is again, not good.” “Two women (8.3%) in the sample reported being sedentary. The favoured activity of women who reported being sedentary was watching television. This most commonly took place in the evenings, after dinnertime. Few participants (17%) reported how long they watched television per day. One 38 year-old Bangladeshi woman (W) describes why television may be so attractive to SA women:Other popular activities done while sedentary were reading and attending prayer groups with friends. During these times women were engaging in religious readings or prayer by themselves or with friends. Women did not report the duration of these activities but broadly indicated that they were afternoons away from the home or during quiet times in the evenings. Results from objective measures conducted with this sample of 24 women indicate that on average this sample of women engaged in 553.2 ± 59.4 min of ST per day (range = 437.4–678.9 min per day). Individual results for the women who participated in the interviews are reported in This mixed-methods study offers useful insights into the perceptions, contextualisations, and sources of PA and ST amongst a small sample of SA women in the UK. It is important to emphasise that because the sampling strategy was designed to recruit a similar percentage of women who were normal weight, overweight and obese as found in the larger study (and as defined by the WHO for SA adults ), this rn = 5) of women actually met recommended guidelines for PA adequate to achieve health benefits. Of the six women who were able to quantify their daily PA, two women’s perceived PA matched the MPVA data obtained from objective measures. However, when examining levels of light intensity PA, all six women were as active as they perceived. This finding highlights the importance of clearly defining and emphasising the intensity level of PA needed to achieve health benefits. SA women may perceive themselves as adequately physically active, but may not be meeting recommendations due to their engaging in a lower than adequate level of activity intensity. As most of these women lead busy lives, and they equate this “busy-ness” to being sufficiently physically active. This finding, in addition to perceiving that engaging in housework is sufficient to meet PA guidelines, identifying lack of time for PA due to prioritisation of household and family obligations, and concerns about personal safety are consistent with studies on SA women and research with other ethnic minority women [(1)prioritising traditionally cooked meals from scratch each day, which takes 2 to 3 h on average;(2)perceiving prayer time  as adequate duration and intensity of PA;(3)abrupt shift in how time is spent once a woman becomes a mother-in-law; and(4)engaging in sufficient duration of PA with little experience or insight into how to exercise at an intensity that is moderate or vigorous.Although the interview data indicated that participants assumed they were sufficiently active (via regular housework and domestic responsibilities), only 20.8%  and older (mothers-in-law) women conceded that this habit was not healthy to engage in. All women recognised that there are health risks that result from leading a sedentary lifestyle. The important influence of family traditions has been found in other studies on SA women ,23,30. TThese concepts and contextualisations have important implications for the use of self-report methods in assessing PA and ST among SA women. Previous research indicates there may be issues with SA women’s interpretation of certain terms and concepts from self-report questionnaires, such as what is actually being captured within the item content of the International Physical Activity Questionnaire (IPAQ) . The finOne major strength of this study is the measurement of both objective measures of PA and ST and participants’ perceived levels from interviews. This approach allows for comparisons and convergence of the two methods. It provides detailed insights into cultural contextualisations of behavioural patterns of PA/ST throughout the day that objective measurement neglects. This includes insights into SA women’s understanding and description of PA/ST in their lives, of which objective measures cannot provide. The use of interviews rather than highly structured questionnaires as a method of collecting PA/ST data allowed for an in-depth exploration of SA women’s own understanding of their activity levels. This study demonstrates not only that SA women may not accurately recall their levels of PA or ST, but provides insights into why this might be the case. Inaccurate recall of PA and ST levels has also been reported in other studies with both ethnic minority groups and the general population ,32. WhilAnother advantage of the comparison of perceived and objectively measured PA/ST performed in this study is that it results in a more in-depth understanding of the types and levels of intensity of activities that SA women currently engage in. The commonly held belief that housework is an activity that helps a person to achieve an appropriate level of PA for health benefits may not be the case if it is not performed at a moderate-to-vigorous intensity level for sufficient periods of time. SA women may believe that they are sufficiently physically active due to their busy schedules and their engagement in light intensity PA, and hence may not recognise the importance of doing additional or higher intensity activity. Health promotion intervention developers can benefit from this insight and build upon the light intensity activities that women currently engage in to promote increasing the intensity of activities performed to achieve the recommended levels of MVPA. A further strength of this study was the inclusion of non-English speaking participants, as these individuals are often identified as “hard to reach”, can be viewed as difficult to recruit, and as a result are excluded from research.This study is not without limitations. By design, the sample is small and is not representative; therefore generalisations about these findings must be made with caution. Purposive sampling was used in order to gain a range of perspectives among SA women since it was not possible to collect and analyse data from a much larger sample within the scope and timeframe of this study. The majority of the women who participated in this study were obese, and were recruited from community centres where many activities are offered for SA women. Consequently, the views of women of normal weight were not fully represented. Additionally, participants were more likely to know what is available in their local area, as well as potentially more likely to know about and participate in PA, than SA women in the general community. Although the high number of obese women interviewed can be viewed as a limitation, we feel this might also be considered a strength, as this is the group that is the highest priority to target for intervention and are considered “hard to reach”. Interview questions about PA and ST patterns did not probe specifically into intensity and duration; however, a comparison of objective PA and ST data with self-reported data using the IPAQ-SF from the larger study in this population indicated that participants significantly under-report both their PA and ST . The resIt is also important to recognise the role of the researchers in interpreting the accounts of the SA women in this study. Researchers bring their own presuppositions and distinctive perspectives into their research, and it is necessary to acknowledge that these can have an influence on the interpretation and understanding of data, results and conclusion . The resFindings from this study suggest that self-report methods of measuring PA and ST among SA women may not produce accurate data due to participants’ misunderstanding of those terms. Therefore it is recommended that objective measurement of PA and ST be used more widely in this group. Since this is not always possible due to cost and time constraints, it is suggested that a more culturally appropriate self-report questionnaire be developed to improve the accuracy of PA and ST data ,37. Whil


The properties of biomolecules depend both on physics and on the evolutionary process that formed them. These two points of view produce a powerful synergism. Physics sets the stage and the constraints that molecular evolution has to obey, and evolutionary theory helps in rationalizing the physical properties of biomolecules, including protein folding thermodynamics. To complete the parallelism, protein thermodynamics is founded on the statistical mechanics in the space of protein structures, and molecular evolution can be viewed as statistical mechanics in the space of protein sequences. In this review, we will integrate both points of view, applying them to detecting selection on the stability of the folded state of proteins. We will start discussing positive design, which strengthens the stability of the folded against the unfolded state of proteins. Positive design justifies why statistical potentials for protein folding can be obtained from the frequencies of structural motifs. Stability against unfolding is easier to achieve for longer proteins. On the contrary, negative design, which consists in destabilizing frequently formed misfolded conformations, is more difficult to achieve for longer proteins. The folding rate can be enhanced by strengthening short-range native interactions, but this requirement contrasts with negative design, and evolution has to trade-off between them. Finally, selection can accelerate functional movements by favoring low frequency normal modes of the dynamics of the native state that strongly correlate with the functional conformation change. On the one hand, they are amazing molecular machines that obey the laws of statistical mechanics. On the other hand, they are evolving machines that are shaped by selective and mutational forces acting on the populations in which they evolve. Simple models of protein folding thermodynamics allow the identification of these evolutionary forces and to better understand and model molecular evolution. In turn, modeling evolution allows a better understanding of the properties and constraints acting on protein thermodynamics. This article aims to review the mutual relationship between models of protein folding and models of protein evolution, in particular how we can use evolutionary reasoning for detecting selective forces that target protein folding thermodynamics and the intrinsic dynamics of protein native states. It does not pretend to be exhaustive, but rather, it will focus on a simple, contact-based model of protein folding and on the results that I and collaborators have gathered with the help of this model.2.i and j along the polypeptidic chain, ijC equals one if the residues are in contact and zero otherwise. We define two residues to be in contact if a pair of heavy atoms belonging to the two residues are closer than 4.5 Å. Since contacts with |i − j| ≤ 2 are formed in almost all structures, they do not contribute to the free energy difference between the native and the misfolded ensemble, and we set ijC = 0 if |i − j| ≤ 2. This representation has some important weak points: it is not continuous; it does not include any repulsion term; and it does not allow angular dependencies, such as those that occur in hydrogen bonds and aromatic interactions. However, its discreteness simplifies the computations and facilitates obtaining analytic insight.Proteins are complex molecules, formed by thousands of atoms kept together by quantum mechanical interactions. The solvent in which they reside, water molecules and ions, plays a key role in determining their statistical mechanical properties. This complexity needs to be reduced to a simple representation, if we want to make quantitative predictions. The representation adopted in this work is based on contact matrices : for eacijC, represents a mesoscopic state in which the degrees of freedom, such as the solvent, exact side chain positions, etc. are averaged out. We model its free energy as the sum of contact interactions, E = ∑i<j CijU, which depends on the nature of the amino acids in contact, iA and jA, and on 210 contact interaction parameters, U, that express the average interaction between amino acids a and b at a given temperature, such as those determined as a statistical potential by Miazawa and Jernigan [A contact matrix, Jernigan ,4,5.S(ijC), decreases with the number of contacts, since mesoscopic structures with more contacts have more constraints. This conformational entropy is difficult to evaluate analytically, and it is almost always neglected in the calculations. Karplus and coworkers showed through normal modes calculations and quantum mechanical calculations that the conformational entropy of a folded protein is large ) per residue, but its contribution to protein denaturation can be neglected, since the conformational entropy of the denatured state can be modeled as the sum of the entropy, due to the existence of different conformations  per residue) plus the weighted sum of the vibrational entropy in each conformation; the latter term almost exactly balances the entropy in the native state, although differences in these terms may have relevant consequences for ligand binding and for the thermodynamic effect of mutations [We have to keep in mind that the conformational entropy associated with a contact matrix, utations , estimatutations ,9,10,11.A protein may exist in several mascroscopic states separated by free energy barriers, the most studied ones being: (1) the native state where it performs its biological function; in this state, the protein is usually folded into a well-defined three-dimensional structure, except for the important case of natively unfolded proteins , which wUG ≈ −UTLS, where T is the temperature in units in which Bk = 1, L is chain length and US is the conformational entropy per residue of an unfolded chain. It has been proposed that the misfolded state, consisting in the ensemble of compact, but wrongly folded conformations, is described by the Random Energy Model (REM) [CLS is the logarithm of the number of compact contact matrices, 〈.〉 represents the average over the set of alternative compact contact matrices of L residues  and a heteropolymer contribution, writing exp(−G/T) = ∑CN exp (− 〈E〉 /T + S(CN)) ∑CC:N exp(−βz), with z = , is approximately the same for all compact structures, and it can be neglected for computing free energy differences.For the sake of simplicity, we neglect the conformational entropy of the folded native state, estimating its free energy as el (REM) , which ael (REM) ,22,23. Iel (REM) :(1)GmiscT, at which the conformational entropy vanishes: cT, the ensemble freezes into a finite number of thermodynamically relevant contact matrices, and the free energy maintains the same value as at T = cT. If the third centered moment of the energy, 〈2〉 , and theG = Gnat − Gmisfolded − Gunfolded, as:ijklmmF = 〈(ijC − 〈ijC〉 (klC − 〈klC〉 (mnC − 〈mnC〉)〉 [Putting together these free energy estimates, we obtain the free energy difference between the native and the non-native states above the freezing temperature, Δ 〈Cmn〉)〉 . The freIn this work, we use the contact interactions parameters that were determined in ,26 by re3.Traditionally, molecular evolution studies have examined the rate of substitution of amino acids in protein sequences without considering their structural context. This situation has become, since less than two decades ago ,42,43,44Following Goldstein and other researchers  is a macroscopic event. Two main factors influence the evolutionary process and, consequently, the stability that an evolving biomolecule can achieve: the effective population size and the mutational process, in particular mutation rates and mutation bias. As reviewed below, we found that population size and mutation bias have an important effect on protein folding thermodynamics. Recombination can be very important as a source of evolutionary innovation, as well, but we do not consider it here, because it is more complex to analyze.G < 0 and zero when ΔG > 0, i.e., it tends to a binary value in which a protein is either non-viable or equally fit as other viable proteins. In this neutral regime, the stability achieved by the protein is almost independent of population size as in the neutral model by Kimura. In Kimura's model, the rate at which neutral substitutions are fixed in a population of N individuals evolving with neutral mutation rate μ is independent of population size, since Nμ neutral mutations arise in a time unit, and the probability that one of them is fixed is 1/N [f ≈ 1), i.e., ΔG ≈ 0, since ΔG ≈ 0 is the most probable stability of viable proteins in sequence space. They proposed that this property of the neutral regime explains why natural proteins are only marginally stable, despite it not being difficult to engineer mutations that increase their stabilityAn important property of the above fitness function is that it presents a neutral regime at low temperature. In this case, the fitness takes approximately the value one when Δd is 1/N . Tavernad is 1/N  showed tA, is proportional to the exponential of its logarithmic fitness φ = log(f), P(A) ∝ exp(φN(A)), i.e., there is a perfect analogy between molecular evolution and statistical mechanics with the effective population size, N, playing the role of the inverse of temperature [φ(A) = − log(1 + exp(ΔG(A)/BTk)), and the distribution of stability in the space of the protein sequences that are visited by evolution is:BTk = 1. Note that the approximation P(ΔG) ∝ exp(−NΔG/kT) is only valid in the first steps of evolution when the protein is unstable, whereas when ΔG/kT becomes very negative, either because the temperature is low or because evolution optimized protein stability, the fitness saturates to its maximum possible value f = 1 and becomes almost independent of ΔG, and we enter a neutral regime in which protein stability is almost independent of population size. The above equation has to be corrected to take into account the mutation process, in particular the bias to mutate to hydrophobic or polar amino acids, which influences the fitness attained in evolution and the corresponding protein stability, see below.At high enough temperature, however, the fitness function perature . In thisG from the protein sequence, A, and the target native structure, Cnat, we can map the genotype into the phenotype of the model protein and perform quantitative studies and simulations of molecular evolution. This mapping is not accurate enough to reliably predict the effect of individual mutations, but there is a good correlation between the effect of mutations predicted through this model and those experimentally measured  tend to be very small and that the evolutionary rate dN/dS  are high and almost independent of population size, as expected in neutral evolution [Despite the success of these models, it is well known in the field that a fitness function only based on folding stability is a poor approximation of the real selection process, which acts on protein “function” (whatever it means). In particular, the ability of proteins to establish specific molecular interactions and their native dynamics may be important targets for selection (see the last section of this review), even more than the stability of the folded state, which has little relevance for the important class of natively unfolded proteins . Anothervolution .i.e., f ≈ 1 if ΔG < 0 and f ≈ 0 if ΔG > 0, yielding a neutral fitness landscape in which the evolution is almost independent of population size and the selective coefficients for viable proteins (ΔG < 0) are very small: Δ log f ≈ exp(ΔG/kT)ΔΔG/kT ≈ 0, where ΔΔG is the thermodynamic effect of mutations. Nevertheless, if the temperature is high, these models are much less neutral, and the properties of evolved proteins depend on population size, as was found, for instance, in the simulations reported below.An important remark with respect to this observation is that the neutrality of these models depends on temperature, as noted above: the fitness function 5.The strategy that we follow here for detecting selection on some protein property relies on comparing two physically-based models, one that includes the effect of selection on the target property and another one that only considers selection on a lower order property (null model). For instance, when we investigate selection on stability with respect to misfolded states , we compare the predictions based on misfolding stability with the predictions of a null model that only considers the stability of the native state with respect to the unfolded state. The model based on misfolding stability predicts that the average interaction energies of contacts that are frequent in the misfolded ensembles should be higher, whereas the null model predicts that the average energies of native contacts should be low. To compare these predictions, we divide pairs of residues into four classes: (A) native and frequent, (B) native and infrequent, (C) non-native and frequent and (D) non-native and infrequent. According to the null model, no difference is expected between class A and B and between class C and D, whereas observed interaction energies show significant differences.dS, is higher than the non-synonymous rate, dN. Genes showing values of dN/dS larger than typical values, but smaller than one, are usually interpreted as a hint that the gene is under relaxed selection, either because the effective size of the population in which it evolves is small or because the phenotypic consequences of its incorrect functioning are not severe. Values of dN/dS > 1, i.e., accelerated evolution at the amino acid level, are usually interpreted as an indication that the gene is under positive selection, for instance due to a change in its function or a change in the environment. Since the dN/dS > 1 criterion is a very strong requirement, more sensitive tests have been developed, such as the McDonald and Kreitman test [dN/dS to the analogous value for intraspecies polymorphisms. However, this test has been criticized for not being able to separate adaptation events from compensatory substitutions, which should be frequent in evolution: the model described by This procedure for detecting stability based on the predictions of physical models can be complemented with methods based on biological models that focus on substitution rates and intrapopulation variability. Nucleotide sequences can be used to infer rates for synonymous  and non-synonymous substitutions separately , althougman test , which c6.i.e., the evolutionary forces that strengthen the interactions formed in the native state.In the previous sections, I briefly presented the models of protein folding stability  and protein evolution  on which this work is based. I will now show that these models allow one to quantify how natural selection acted on several aspects of protein folding, starting from positive design, U, by measuring how the frequency of pairs of amino acids of type a and b that are in contact in structures from the PDB deviates from a null model that assumes the absence of interactions: contact parameters are estimated as Ustat = log /Pnull(ijC)) [P(A1 ⋯ LA) ≈ ∏ij Pij , and determining the distribution of maximal entropy with the constraint of fixed average native energy E̅ = ∑A P(A1 ⋯ LA) ∑ij CijU, i.e., considering only positive design . The contact interaction parameters, Ustat, extracted with the above Boltzmann-like formula present a very strong correlation with the U parameters used in this review [r = 0.97, Minning, Bastolla and Porto, Pairwise amino-acid distributions from structurally constrained protein evolution, preprint) support the view that statistical potentials derived from database analysis or optimization criteria reflect relevant physical interactions underlying protein evolution.As first realized several years ago by Finkelstein and coworkers , the disll(Cij)) ,61. Diffs review , which wet al. [A further interesting support to this view comes from the recent work by Lui and Tiana , who appet al.  to obtaiet al. . Further7.P(1A ⋯ LA) as the product of single site distributions, P(A1 ⋯ LA) ≈ Πi Pi (iA), we can compute iP(iA) as the distributions that maximize the entropy in sequence space for a given value of stability, ΔG. To simplify this computation, I and coworkers adopted the hydrophobic approximation, which consists in approximating the contact interaction parameters with their main spectral component, which is related to hydrophobicity [ϵ < 0 and h(a) is correlated with several empirical hydrophobicity scales [E = ϵ∑ij Cijhihj, with ih = h(iA), and we can analytically determine the sequence that minimizes the energy for a fixed value of ih (a sequence signature), is proportional to the effective connectivity (EC), ic [iP(a), can then be computed as the distribution of maximal entropy subject to the constraint on its mean value. The result is a Boltzmann-like distribution, iP(a) ∝ exp(−ihβ (a)). In the absence of selection, iP(a) would be the distribution given by the mutational process. Therefore, iP(a) is the distribution with minimum Kullback–Leibler divergence from the mutational distribution, Pmut(a), i.e., iP(a) ∝ Pmut(a) exp(−ihβ(a)), where the selection coefficient, iβ, expresses the strength of natural selection at each position , and it can be determined by imposing the constraint ∑a h(a)iP(a) = iαc + b. We have verified that this distribution is in very good agreement with the site-specific distributions obtained through simulated evolution with stability constraints [if(a), to the above equation allows for the determining of the 21 parameters, Pmut(a) , α and b, and to compute the exponent, iβ. Note that iβ depends on the mutational distribution, Pmut(a). For instance, if mutations favor hydrophobic amino acids, selection will be stronger at exposed positions where selection favors hydrophilic residues. Conversely, if mutations favor hydrophilic amino acids, selection will be stronger at bulk positions, where hydrophobic residues are preferred [A similar reasoning allows one to analytically compute site-specific distributions (profiles) of amino acids at different positions in a protein family. If we approximate hobicity :(6)U, ci , a struc(EC), ci . The constraints ,41, and straints . For a greferred .7.1.L−1/3. Therefore, longer proteins tend to have more contacts per residue: cN/L ≈ c (1 − bL−1/3)  see , and theG is very negative, so that the fitness, f, is close to saturation, there is a neutral evolutionary regime in which we expect that proteins achieve only the marginal stability that allows their functioning. In this regime, we expect that the absolute value of cN/L or, which is the same, with chain length; in other words, individual native contacts are expected to be weaker for longer proteins. This prediction has been verified for a representative set of of proteins in the PDB [cN/L, i.e., native interactions are less optimized; see h〉, first increases with chain length, since the number of bulk versus surface residues increases, but then it reaches a maximum and decreases, i.e., very long proteins tend to be less hydrophobic [As we have seen above, when the physical temperature is low or Δ the PDB ; see Figrophobic , which h8.Negative design, named in this way by Berezovsky and coworkers  and HoroTo investigate selection on sequence composition, we divide amino acids into three classes: hydrophobic {L, I, V, F, Y, C, W, M}, polar and charged {D, E, G, S, N, K, R} and others {A, T, H, Q, P}, and we compared observed frequencies to a null model that takes into account that the sum of frequencies is one . We founijC, is a decreasing function of the contact range l = |i − j|, short-range contacts occur more frequently, and they are weakened by a negative design. However, to observe this effect, we have to discount the effect of positive design by separating contacts that occur in the native state from those that do not. We define the contact frequency energy score (CFES) as the correlation between contact frequency, 〈ijC〉, and contact energy, U, distinguishing the set of native and non-native contacts. We observe that the CFESs are positive, i.e., native contacts that are short range are associated with energies that are, in general, higher than for long-range native contacts [i.e., the values of the CFESs are strongly significant, which suggests that they are due to selection for negative design , three  and four different indexes, and measured the correlation coefficient between contact correlations 〈ijCklC〉 − 〈ijC〉 〈klC〉 and energy products UU, which we call the contact correlation energy score . Also in this case, we have to distinguish native and non-native contacts. All the CCESs are positive and significantly higher than their reshuffled version, which indicates that the second moment of the energy of misfolded conformations is higher than expected based on composition and native contacts alone, suggesting that natural selection is able to improve negative design by acting on contact correlations, as well [Negative design also acts on contact correlations. We distinguished pairs of contacts,  as well .Zscores of the CFES and CCES with respect to shuffled sequences are significantly larger for native contacts, which are fewer and stronger, than for non-native contacts. These Z scores are larger for proteins with more negative interaction energy , as well as for longer proteins, in agreement with the expectation that these proteins experience stronger selection for negative design [The e design .9.i.e., |i − j| is small), and, therefore, are more easily formed, interact more strongly, i.e., U is more negative [i − j| and their interaction energy, U. However, we have seen in the previous section that negative design promotes a negative correlation between |i − j| and U, since increasing the energy of frequent contacts with small |i − j| destabilizes misfolded conformations. These two design principles cannot be achieved at the same time, which induces frustration in protein evolution. Nevertheless, despite the signal for negative design being stronger, the signal for selection on the protein folding rate can be detected from a statistical analysis of the PDB [i − j| ≈ 8. For longer ranges, the energy increases with |i − j|. This trend cannot be attributed either to positive or to negative design. If we adopt a method similar to the one described above and described in more detail in [Plotkin and coworkers developed a model that predicts that the protein folding rate increases when contacts that are short range along the sequence , tend to be hydrophobic, while proteins coded by genes rich in guanine and cytosine tend to be hydrophilic . This particularity establishes a deep relationship between the mutation process and protein folding thermodynamics. We tested this relationship with simulations of protein evolution subject to different mutation biases, finding that mutation bias towards AT produces proteins that are less stable against misfolding, but more stable against unfolding  see Fig.We tested this relationship through a statistical analysis of the predicted folding thermodynamics properties of orthologous proteins present in the genome of different bacteria . IntraceUx  and Mx , which we normalize with respect to the sequence in the PDB. This setting allows for highlighting the fact that these two kinds of stabilities respond differently to mutation bias and population size. For this study, we use the following fitness function:S, has the role of a neutrality parameter: if it is large, the fitness tends to a binary variable, and the value of fitness attained in evolution is independent of population size . To gain insight into the interplay between these two properties, we simulated protein evolution with a fitness function that separates stability with respect to the unfolded ensemble and with respect to the misfolded ensemble. We evaluate these two kinds of stability through the variables, size see .This model shows that the fitness attained in evolution depends not only on population size, as it was known, but also on mutation bias . Namely,11.The previous part of this review concerns protein folding stability, modeling proteins as static entities and representing the native state as an individual contact matrix. However, proteins are extremely dynamic, and even in the native state, they explore a fairly large amount of configuration space. As mentioned above, it is often assumed that this configuration entropy can be ignored, since it is expected to have similar values in all compact conformations, both native and non-native, so that its contribution to stability is negligible . Neverthi.e., all native interactions are stabilizing and all non-native interactions can be neglected. The ENM force field is defined as:ijC is the contact matrix, ijr is the distance between atoms i and j and f describes a pairwise interaction that attains its minimum when f does not depend on the type of atoms, but only on the distance, ij. The statistical mechanics of this model can be exactly computed through normal mode analysis. Normal modes are independent perturbations of the equilibrium configuration that constitute a complete set of vectors. They can be computed by diagonalizing the Hessian matrix of the second derivatives of the energy with respect to the coordinate systems. If we use degrees of freedom that are not Cartesian, such as internal coordinates, we have to consider the generalized eigenvalue equation H is the Hessian matrix in internal coordinates, T is the kinetic energy matrix and αω is the frequency of normal mode α. By the equipartition theorem, the average energy of the system distributes uniformly across all normal modes. Since the energy associated with a normal mode is the product of its squared frequency times its mean square displacements, the contribution of a normal mode to the intrinsic motion of the molecule decreases with its frequency, i.e., low energy normal modes generate larger internal fluctuations.The simplest model that can analytically predict the intrinsic dynamics of proteins in the native state is the elastic network model (ENM) , proposeα, to a generic conformation change, Surprisingly, despite normal modes being only valid for very small displacements, it has been observed that low frequency normal modes that describe the collective motions of proteins, such as inter-domain motion, correlate very well with observed functional conformation changes ,85. In pmodel in , findingρ is significantly positive, low-frequency normal modes contribute to the conformation change more than expected based on the null model. In turn, this has the effect of reducing the harmonic energy barrier with respect to a conformation change that obeys the null model and has the same RMSD. On the contrary, if ρ is significantly negative, low-frequency normal modes are underrepresented with respect to the null model, and the harmonic energy barrier is larger than expected. Therefore, significant ρ > 0 suggests that natural selection acted on the intrinsic dynamics of the native state in such a way as to favor functional motions. We found that most conformation changes in the PDB are well described by the null model, but a large number of conformation changes has significant ρ > 0, in particular those involving the formation of homo-oligomeric protein complexes, proteins that transport ligands and phosphorylated proteins [ρ can be interpreted as the result of natural selection to avoid a particular conformation change from happening spontaneously. Notably, we find some examples of ρ < 0 in regulatory proteins, for instance for conformation changes upon phosphorylation [Based on this null model, we can then measure excess correlations between proteins . Conversrylation .12.Simple models of protein folding and dynamics allow one to propose a hypothesis on which quantities may be the target of natural selection acting on protein stability and dynamics. These hypothesis can be tested by comparing statistical observations made on representative sets of natural proteins with suitably built null models. As a result, we can ultimately detect the fingerprint of natural selection acting on the positive and negative design of protein folding stability, protein folding rates and the intrinsic motion of proteins. Through these studies, a synergy between physics and biology is created: evolutionary arguments allow one to test and better understand protein folding, and protein folding models allow one to better understand and model evolution.


Introduction. There are not enough studies about the barriers to lose weight from the perspective of children and their parents. Methods. Children and adolescents diagnosed with overweight/obesity in the Department of Endocrinology and their parents were invited to participate in a series of focus group discussions (FGD). Twenty-nine children 10–16 years old and 22 parents participated in 7 focus groups; 2 mothers and 2 adolescents participated in depth interviews. All interviews were recorded, transcribed, and analyzed through grounded theory. Results. Parents went to the hospital only when their children presented any obesity complication; for them, overweight was not a health problem. Parents referred to lack of time to supervise about a healthy diet and exercise; besides, the same parents, relatives, friends, and the mass media encourage the consumption of junk food. Children accepted eating a lot, not doing exercise, skipping meals, and not understanding overweight consequences. Both, parents and children, demanded support to do the time recommended for exercise inside the schools. They also suggested getting information from schools and mass media (TV) about overweight consequences, exercise, and healthy food by health workers; they recommended prohibiting announcements about junk food and its sale. Conclusions. The barriers detected were lack of perception of being overweight, its identification as a disease and its consequences, lack of time to supervise a healthy lifestyle, and a big social influence to eat junk food. Rates of severe childhood obesity have tripled in the last 25 years, with significant differences by race, gender, and poverty . In 2006Qualitative research has the goal of explaining the sociocultural world through self-experience of each person acting as theoretical and methodological livelihood; use techniques and designs to get, analyze, and interpret information ; the results are not expressed numerically , 11. PreThe aim of this study was to identify the barriers to lose weight, including the weight status perception, beliefs, habits, opinion of social support, and recommendations from the perspective of children being overweight or obese and their parents, in order to improve the interventions of overweight/obesity in children considering this information.Participants (children and parents) were recruited from a Pediatric Endocrinology Unit by a pediatrician who contacted them in the waiting area or by phone since a record of children with the diagnosis of overweight or obesity. Eligibility criteria included age (10–18 years old), male or female, overweight (body mass index (BMI) ≥ 85th percentile for age and gender) or obese (BMI ≥ 95th percentile for age and gender), and parents with a child diagnosed with overweight or obesity. The study was approved by the Research and Ethic Committee of Children's Mexico Hospital Federico Gomez and written informed consent was obtained from all parents and children.A focus group is a technique of the qualitative method to describe and understand interpretations, perceptions, and beliefs of a group (6–10 persons) with a common problem , 19. TheFocus groups were formed by a moderator-social psychologist, an observant—a physician, and 6–8 children or parents. The observant was a pediatric endocrinologist independent of his/her assigned doctors. There were 4 groups of children, 2 of girls (10–14 and 15–18 years old) and 2 of boys (10–14 and 15–18 years old), and 3 groups of parents, 2 of mothers (younger than 40 years old and older than 40 years) and 1 of fathers (every age). Four interviews were made in depth to complement the information: 2 mothers (28 and 45 years old) and 2 adolescents (girl of 13 years old and boy of 15 years old).The guide for interview was made by literature review –9, 12–15Example of Coding Scheme for Themeweight status perception,weight status perception in children,reasons to buy fast food,limited time to prepare healthy food,limited time to be with children,economical limitations,poor understanding of healthy diet and habits,poor understanding of consequences of overweight.Limitations to lose weight are as follows:Twenty-nine children and 22 parents participated in this study. The 51.7% were female and the median age was 15 years (10–17 years old). All children presented body mass index (BMI) in percentile 85 or higher. 82% of parents had overweight or obesity and only 22.7% of the children had parent participants in the focus groups. The mothers interviewed in depth were 38 and 45 years old, respectively, the girl 12 and the boy 15 years old.We identify 4 principal themes : limitat(1) Lack of Overweight/Obesity Perception. Almost all parents did not perceive overweight or obesity in their children; they went to the hospital for acanthosis nigricans, hypertension, asthma, or other health conditions but not for the weight of their children:I never imagined that she was overweight… when we saw the problem of her skin… consulted a dermatologist and because of the dark neck, told us that she had to go with an endocrinologist… .(2) Guilt about Abandoning Their Children. Parents expressed feelings of guilt about leaving their children for a long time for their work and compensating them with a lot of food that they like, videogames, or anything that children demand:… His dad thinks that it is giving back to the girl, the fact that it is not a lot of time with her: - Daugther [sic], these are for you, some cookies, small cakes, pizza, Chicken Happy- . (3) Lack of Time to Supervise the Children. Mothers do not have time to supervise diet and exercise of their children; some of the mothers offer their children fruits and vegetables but they do not eat them:… I cannot leave work… I want to be all the time with her and really be supervising it .I find the rotting fruit of a very long time… .(4) Economical Limitations. The parents do not have enough money to buy fruit or healthier food for each member of the family:What concerns me more is the economic part I think that's why I cannot give everyone all the fruits required… it does not reach… are five meals,… three or more fruits and vegetables… . (5) Lack of Information about Healthier Food and Overweight/Obesity Consequences. Parents and children did not have an understanding of healthy diet and consequences of overweight because they did not receive a complete explanation about it in the past:I had been carrying with several doctors and did not allow him to be a diet so well what it is like now that you say, such a thing is worth so many calories and you can eat as many servings… (Father interviewed).1) Skipping Breakfast or Any Other Time of Food. Most of the children participants did not have breakfast due to lack of time or appetite, as well as lunch or dinner:… I only had time wash up, I did not have time for breakfast and in my school I did not eat, until I were returning home on the night I took dinner . (2) Insufficient Rest (Short Sleep). Children go to bed very late because they arrive late at home, do homework, use the computer, play videogames, watch TV, or wait for their parents to come back from their job.(3) Disorder on Weekends. Children and even parents wake up almost at noon, do not respect schedules or quality of their food, do not combine correctly the food groups or their quantities, and usually underestimate the amount of food:The only thing that I eat in the evening it is one liter of milk and two loaves of bread .(4) Lack of Security, Money, and Time to Do Exercise. For parents it is better that the children are entertained watching TV than in the street exposed to danger; this way, the parents are able to finish work at home. Children mentioned lack of time, nearer places, and money:… Is the lack of time… and the other is the insecurity… if you are not with the children is very dangerous, it is the main factor in that the children are locked up (Father interviewed).Comfort for ourselves, if they are entertained watching TV, they are not giving us problems; and we can finish our tasks home… .I practiced Zumba, arabic dance and hawaiian… but the teachers are no longer going, I was in karate, but by issues of money, I couldn't continue. I was swimming but now for my school I do not have time to go .(5) Practicality and Rejection of the Natural Water. Several parents said that buying a soda is cheaper and faster than preparing water with fruit. Natural water is unacceptable for several people. “… my husband tells me that doing water with fruits is more expensive that buying soda… the water, sugar, fruits.” “At home it is a sin eating accompanied with natural water, poor children, how is possible they drink natural water with the food…” (Focus group of mothers younger than 40 years old).(6) Refusal to Eat Vegetables. The belief “vegetables for animals” was not present in adolescents participants, but some of them have heard it from grandparents, parents, or friends of their parents. “A friend of mom, was eating and told than the lettuce is for animals” .(7) “Children in Growth Should Not Restrict Their Food.” Some mothers expressed the idea that children should eat a lot because they are growing. In fact, they expressed that thinness indicates disease and overweight means good health. Adolescents do not share this belief but do not want to be too thin.It was normal to listen-Pretty child, he is cute so chubby-…. When children are heavy, we are happy… when people saw my daughter so small and thin, they told me - your child is underweight, she looks sick… .… I would like to be thin, but not too much .(1) Giving Junk Food in Excess as a Display of Affection. Fathers, friends, and mass media improve excessive junk food consumption as a display of affection. “… my daughter received a box of chocolate candies when she was operated….” “When we lived in the house of my parents, they told us - How is possible that my grand-daughter does not eat sweets, this is traumatic”  (Focus group of mothers ≥ 40 years old).… because my sons watch toys in the announcement TV of any food and they tell me buy me it or that….. With this type of announcementes [sic] call children, with offerings such as buy 1 and take 2, my son tell me—it is cheap - (Mothers < 40 years old). (2) Poor Support from Schools. In several schools fast food is sold; in fact, there are no options to eat healthy food. “… In the school, there is a specific place to sell maruchan soup and it is the first to be sold, fruits and vegetables are not sold, only maruchan soup, cookies, snacks and sweets” .(3) Lack of Clear Information about Obesity Consequences and Healthy Diet. Physicians do not explain enough the consequences of obesity and the meaning of a healthy diet. In addition, they scold mothers if their children do not lose weight, although some teens prefer that their doctors speak hardly about consequences in order to understand why they need to change. “… physicians do not explain us the things… a pediatrician told me the true but very kindly, the other pediatrician told me very serious the true and now I am changing” .(1) Support from TV and Mass Media to Disseminate Information and Regulate Publicity of Junk Food. Children and parents recommended TV programs about healthy diet and consequences of overweight because all people watch TV. “… more information in TV because it is the principal mass media, in TV, the experts must explain about diseases caused by the overweight…” .(2) Real Support from Schools. Parents considered that the school must also educate children about healthy lifestyle because children stay there most of their time. Children also were interested to learn about healthy food and overweight consequences in the school, by health workers. They recommended prohibiting the selling of fast and junk food and placing dining rooms offering healthy food. They also suggested that children do exercise on recommended time inside schools: “The actions should be directed in the schools because it is where children are the greatest time…” (Focus group of fathers).(3) Example from Parents. Parents realize they must practice being a good example. “I feel that if I lose weight, it would be the best motivation for my son” . encourages the change toward healthy habits in children , 28. In Another important barrier is the lack of understanding about overweight consequences. In fact, all parents and children participants, especially, the oldest, demanded a clear explanation about it. This clear explanation would be the best strategy to motivate parents and children to lose weight  and to fParents feel guilty leaving their children alone for their jobs and, as compensation, they buy them junk food. In addition, this sense of guilt also limits their authority even more if the same parents are unable to follow a healthy lifestyle , 30. ParSeveral authors have reported, from the perspective of physicians interviewed, that the therapeutic success is low because patients and relatives do not have motivation, there is no family support, the mass media influence their elections of food, and there are no brochures more comprehensive and practical on healthy eating and exercise –37, and n = 816) or serve as a control (n = 408). The intervention was carried out in primary schools and it consisted of education on healthy habits, modification of distributed food, and physical activity. Until after three years, intervention resulted in a lower increase of BMI  and a decreased consumption of total calories, bread, fat, and sugar consumption in the schools [Interventions in secondary schools have improved the sale of food , 38–40,  schools . On the  schools . In fact schools .The principal limitation of this study was at the same time a stronghold because our participants were already alive to the problem. In the past, they did not perceive the overweight in their children, did not identify it as a disease, and ignored the consequences and the best way to eat; now, they had more knowledge to give recommendations in order to decrease the weight. However, the perspective could be a little different, interviewing people without the perception of overweight/obesity in children and their parents.In conclusion, the barriers detected in this study have similitude and differences with other big cities. The intervention programs must consider the lack of perception of being overweight/obese, its identification as a disease, and its consequences; the lack of time of parents to supervise diet and exercise of their children; the great influence of relatives, friends, school, and mass media to eat junk food and the possibility to educate about it from schools and mass media  by health personnel.


Violence against indigenous women and girls is endemic, yet the absence of research on the consequences of this violence from the perspectives of women presents a profound barrier to the development of knowledge, along with violence prevention and mitigation. Although family is central to many indigenous communities, existing research typically examines the consequences of intimate partner violence (IPV) on women or children in isolation, rather than examining its consequences holistically.The purpose of this article is to identify US indigenous women's perspectives about the impact of IPV on women, children, and families.Data were collected with 29 indigenous women affected by violence from a Southeastern tribe in the United States. As part of a larger critical ethnography, pragmatic horizon analysis of life history interviews revealed the consequences of IPV across multiple levels.Women reported profound psychological consequences resulting from IPV. The majority of women had witnessed IPV in their childhood, providing support for an intergenerational cycle of violence. Women reported psychological consequences on children, which paralleled those reported by women, leaving deep impressions on children across their life course. Consequences on children and whole families were extensive, indicating the negative ramifications of IPV transcended personal boundaries and affected children and families across multiple generations.Given the tight-knit nature of indigenous families and communities, the consequences across individuals and families were noteworthy. However, a dearth in research examining consequences of IPV across levels fails to capture the interconnections of consequences for women, children, and families. Given the centrality of family in many indigenous communities, examining IPV from a holistic perspective that incorporates multiple levels is recommended for IPV research and intervention development. However, the absence of research on the experiences of indigenous women and girls specifically, presents a profound barrier to knowledge development and violence prevention and mitigation (United Nations, Given the centrality of tight-knit families in many indigenous communities (Burnette, Despite the paucity of research on IPV among indigenous women in the United States Bohn, , researcThe psychological consequences of IPV are significant. Victims of IPV are more likely to report depressive symptoms, substance abuse, and chronic mental illness than non-victims (Coker et al., Another major impact of IPV is their attendant negative effects on children (Graham-Bermann & Perkins, In addition to negative consequences from IPV for partners and children, Sturge-Apple et al.  reportedThe literature on effects of IPV on women, children, and families is predominantly quantitative studies, which produce a broad understanding; however, qualitative studies are necessary to understand the particular complexities of IPV and its consequences across multiple dimensions. Given the aforementioned gender differences (Moretti et al., As part of a larger critical ethnography (Burnette, The centrality of family in indigenous communities tends to be paramount (Burnette & Sanders, extended families, which can include family members related by blood, along with clan, tribe, and adopted family relationships (Waller, Okamoto, Miles, & Hurdle, Life history interviews followed a semi-structured interview guide to answer the research question: What are indigenous women's perceptions of the consequences of IPV on women, children, and families? We define families to include pragmatic horizon analysis, which enables explicit and implicit meaning of data to be uncovered (For a comprehensive description of this analysis as applied to this research, see Burnette, Data were analyzed using the method outlined by Carspecken  pragmatiParticipants, aged 22–74, all had a high school diploma, and 33% held a bachelor's degree or above (see Burnette, She went through getting hit on the back of the head with a crowbar. She lost all her top teeth, as a result, for one domestic issue. I think he even attacked her with a knife and caused some damage to her hands. She is in very poor health now.Among participants, 65% of women spoke about personal consequences of IPV. Women tended to report severe and often life-threatening forms of abuse. One woman spoke about family members’ experiences with IPV:Indeed, women's experiences of IPV often resulted in trips to the hospital for medical treatment. A woman recalled, “He started hitting me, and I remember him knocking me down, and I guess he kicked me on the back of my head; and next thing I know, I was in hospital.”Women reported psychological consequences, including PTSD, depression, and suicidal symptoms. Suicidal thoughts were frequently reported as consequences of IPV. One woman stated, “I was so tired that I even contemplated on suicide.” A woman recalled the aftermath of IPV for her family member, stating, “Twice she had attempted suicide. … she tried to overdose some medicine, some pills.” Other women reported significant depression. As a woman recalled, “I went through some depression. … I tried to go back to work, I just couldn't—I couldn't function.” One woman recalled the severity of her mother's depression after experiencing chronic IPV, “She holds on to it and it—it destroys her.” She added, “She has been admitted into a mental hospital like about three, four times. She has been through electric shock therapy.”I couldn't get enough sleep because I was always having nightmares that he was coming to get me. And whenever I heard a noise around the house I kept thinking, you know, “He is here, and he has found me.”Posttraumatic stress symptomatology was frequently reported by women who experienced terror and fear of the perpetrator, even after the relationships ended. As a woman remembered, “It's horrible to go through that abuse, to be fearful all the time. What's going to happen next? What's going to happen when I leave home?” As another woman explained, “Psychologically he was in my head like all the time; every time I heard a noise, I thought he was coming to get me. I had nightmares that he was coming to get me.” This could lead to insomnia, as she added,It was always something wrong with my decision or my choice, and of course, he [perpetrator] always had a better choice … Now I find myself [when her current partner asks], “Where do you want to go out” [she replies] “It doesn't matter.”As indicated, the consequences of IPV often persisted beyond the boundaries of the violent relationships, and women reported the ways it affected their relationships with others. A woman commented on her inability to trust after experiencing life-threatening IPV, stating, “I try not to get close to anybody as far as having feelings and trusting them.” Other women spoke about difficulty making decisions on their own. One woman stated, after her partner had controlled every aspect of her life, “Even in terms of small decisions like … what brand of toilet paper do you use?” She remembered,This was a change from describing herself as “sure of myself” prior to the violent relationship. Another change she noted, “I would have accepted responsibility for everything [in the relationship] and … minimize his responsibility in the relationship, whereas I was not like that before.” By these results, it appeared that some women became conditioned to survive in the abusive situation by accommodating the partner, and this patterning affected their’ subsequent relationships.We have children who witnessed neglect, who witnessed abuse, who witnessed IPV in their home. And it will always continue unless we can change something. And just like the boys, you hear them make the remarks, “I am never going to do what Daddy does to Mom,” but they do; because they have been conditioned that, this is acceptable. I mean, even though they may not accept it in their mind, it's a way of life.This psychological conditioning aspect was apparent in the ways children were affected by exposure to IPV, and 64% of women spoke about consequences of this exposure. As one woman explained,I actually saw him [father] take a pistol and hit her on side of the head, which caused her to go to the hospital … so it [the IPV I witnessed as a child] kind of applied to my marriage. Even though she was in the hospital with the injuries she had, he went to hospital and tried to finish her off over there, they had to call the cops.Many of women's earliest memories were of traumatic IPV. As a woman recalled, “The first memory I really had is of him [father] beating her [mother].” She added, “He beat her and we hid under the bed.” Another woman elaborated on the intergenerational cycle of witnessing IPV and experiencing it as an adult:Some children were caught in the crossfire of IPV, as explained, “I remember my sister yelling at my dad and telling him that it's his fault for going and screwing another woman, and because of that, he started yelling and trying to hit her.”He [father/perpetrator] is holding her [mother] down … and he is literally this [motions] close to her face and he is screaming, screaming, and screaming. … I'm just kind of standing there watching … so when she is coming through the door, he shuts the door to where literally half of her is in the room … and he is pushing it and pushing it, and pushing it.Women spoke about the consequences of children witnessing IPV. A woman recalled traumatic symptomology and felt frozen when witnessing IPV. She recalled,Numerous times, this woman mentions watching in a frozen state in relationship to the trauma, as she described, “It was pretty much violence every day. Whenever they are fighting I kind of go back to that place where I'm just watching.”One woman remarked on the psychological consequences of her children witnessing the IPV she experienced. Her children reportedly identified with the perpetrator after the relationship ended, as she explained, “They [children] were still telling my ex, where I was going, where I was staying, who I was seeing.” Likewise, a woman spoke of how a family member's children taunted their mother as her perpetrator did. This woman had made several attempts at suicide and her child would call her names, saying, “Shut-up, ‘Suicidal’.” Still another of her children demonstrated profound suicidal and aggressive behaviors, as she stated, “He tied up somebody else and had a knife on him.” This adolescent may have been reenacting the IPV he witnessed throughout his upbringing or dealing with his emotions in the way that was modeled to him.Some women spoke of mental health consequences of their exposure to IPV as children including “bipolar” disorder, “depression,” “insomnia”, and “adult ADHD [attention deficit hyperactivity disorder].” One women stated, “I have actually been in the hospital four or five times … I was very suicidal.” Although her children provide her purpose to maintain focus in her life, suicidal thoughts have recurred, as she stated, “I think about death a lot. … I have like no desire to live.”I think she is the one that wanted a father the most and it hurt her the most. The way he treated her, the way he wasn't there for her when she would beg him to take her fishing … he was “too busy” to do that.Children were not only directly affected by witnessing IPV, but were also indirectly affected by the concomitant unmet need for love and nurturance. One woman described her child, as stated,This child resorted to self-harm to cope with her pain. Another woman who witnessed IPV as a child described resultant depression and how she, “turned into a cutter for a while, I used to cut until probably I was 17.” She tried to fill her need for a nurturing father by picking partners that resembled him and, “looking for that love, that acceptance.” She remembered thinking, “He has got to love me somewhere deep down inside.” These attempts to recreate an experience where she felt the love she desired were relevant to her re-victimization, as she reported experiencing child sexual abuse and rape.Often women recounted families and friends being significantly affected by their loved ones’ experiences of IPV, and 52% of women spoke of this. IPV tended to affect multiple family members intergenerationally. One woman spoke about IPV affecting not only her mother but her own life and the lives of her siblings. She recalled, “My brothers, they've done the same thing to their girlfriends or their wife. … My husband at one point had done the same thing to me.” Still another woman recalled how this violence was normalized, “My brother, he was very, very abusive to his wife, I mean, where he would literally pull her by the hair, and to him, it seems like it was okay.” Another woman understood the tolerance of IPV to be due, in part, to many family members experiencing it and it being normalized within the family. She stated, “With my family, especially with my grandmother and my aunt there. To them it was very acceptable for it to happen, they would never be angry at him for doing anything that he did.” She explained, “His sister was beat by her husband, my grandmother was beat by my grandfather, so to them it was very acceptable.”I spent some time at their house. I remember one morning, I just heard him [perpetrator] saying, “Get back in here”. … And just like that, he snapped and just started beating up on her right there.Because many families were multi-family households, at least temporarily, if one family was affected by IPV, all members of the household were affected. One woman recalled witnessing her family member's experiences of IPV, remembering,Multiple participants had been affected by loved ones being killed through IPV. The profound effects of these deaths transcended the boundaries of blood-relation family members and into adopted friends as family members (Waller et al., Results indicated insidious consequences of IPV on indigenous women's lives across multiple dimensions. Women's experiences with IPV had lasting effects across their lives–not only on their mental health–but on their quality of life and personal relationships. Given the tight-knit nature of the indigenous communities and families, the majority of women, not only experienced IPV, they were exposed to it as children and through friends or family members. Thus, even if a woman escaped personally experiencing IPV as an adult, she was likely affected by loved ones’ experiences of IPV. Women who experienced IPV tended to experience especially severe and life-threatening abuse, a finding supported by existing research (Bachman et al., Consequences of IPV on children were also extensive. Lending support for social learning theory, women expressed the intergenerational nature of violence, where exposure to IPV normalized it as a coping mechanism for conflict resolution resulting in an increased risk for being a victim or perpetrator of IPV (Cannon et al., Finally, the consequences of IPV on family included what appeared to be secondary trauma and fear that their loved one would be severely hurt or killed. Women who witnessed IPV in their upbringing described family members being victims and perpetrators of IPV, further supporting the intergenerational transmission of violence (Cannon et al., This culturally sensitive research highlighted the voices of women who were directly and indirectly exposed to violence as children, adults, and family members, using a culturally congruent and rigorous ethnographic method with extensive validity requirements added to its credibility and trustworthiness. Women's recollections brought their lived-experiences of IPV and witnessing IPV to the forefront in a way that is absent in existing research. In addition to psychological consequences, this research added understanding to the consequences on women's subsequent intimate relationships, such as decision making and responsibility, and this information may explain how experiencing IPV places women at risk for subsequent abuse. The profound consequences of experiencing IPV or witnessing parents’ violence provided insight into some of the ways witnessing IPV may affect children's psychological development across the lifespan. Few studies examine the ripple effects of IPV on family, and this investigation documented the extensive consequences on family members. This research has also demonstrated the importance of qualitative research in the study of effects of IPV on women, children, and families by bringing to the fore the complex experiences and consequences of suffering IPV.Limitations of this research included information being based on self-report from adult women. Despite themes being strikingly consistent across women, the reliability of self-report data can vary. Because some women recalled memories from the past, this information may differ from recollections of those who currently witness or experience IPV. Qualitative results cannot be generalized to other indigenous communities, but many factors may translate to other communities. This is especially the case given the close-knit nature of many indigenous communities. Although there may be variances across indigenous populations, family has been a central theme and may serve as a protective or risk factor, depending on the circumstances (Burnette, Sanders, Butcher, & Rand, Although this research is specific to indigenous communities in the United States, results likely translate to other tight-knit families across international contexts. These findings highlight the interconnected consequences of IPV across individual and familial levels, and reveal a gap in knowledge about these likely interconnections among the general population. Thus, these qualitative findings can be incorporated into future qualitative and quantitative research to evaluate their relevance across contexts. Distinct factors that emerged within results, such as the consequences of IPV on women's decision making, future relationships, and family processes; these factors can be incorporated into survey-research or in-depth qualitative research to explain their underlying mechanisms related to IPV. Future research on the perspectives of perpetrators, children, families, and professionals would add important information to existing knowledge. Comparing across indigenous communities with more localized examinations of the consequences of IPV on indigenous populations is needed, given contextual variability. Finally, culturally specific interventions incorporating the whole family are needed, given the ramifications of IPV throughout the family and across generations.