Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed ...Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.展开更多
At present, China＇s basic old-age insurance system has been established and develop gradually. To learn advanced endowment service concept and method, meet the demand of higher level of pension services has become th...At present, China＇s basic old-age insurance system has been established and develop gradually. To learn advanced endowment service concept and method, meet the demand of higher level of pension services has become the new target and task of the urban pension service system development. The appearance of Wisdom endowment concept is to resolve the diverse endowment risk of the elderly, and meet a higher level elderly pension service demand. However, wisdom pension in our country is still in its infancy, its further development is facing many difficulties. As to these difficulties, the author of this paper will analyze from four aspects, the system, the object, technology, talent, and put forward some suggestions for promoting the development of the wisdom of endowment respectively, and make wise pension industry in China can better meet the diverse needs of the elderly for pension, and construct a harmonious society of＂sense of security＂.展开更多
Entrepreneurship quality education is not only the standpoint and focus of entrepreneurship education, but also the key point in entrepreneurship education. In this paper, based on three aspects （the educated, the su...Entrepreneurship quality education is not only the standpoint and focus of entrepreneurship education, but also the key point in entrepreneurship education. In this paper, based on three aspects （the educated, the subjects implementing education, and external environment）, the main factors restricting the entrepreneurship quality education for the young peasant workers back to hometown in Yunnan province are analyzed, and also the governmental strategies of a clear purpose and a powerful applicability are further explored.展开更多
＂Environmental Impact Assessment Law of P. R. China＂ was promulgated on Oct. 28^th, 2002 and has been put into effect on Sep 1^th, 2003. This paper puts forward some important factors which restrict the development ...＂Environmental Impact Assessment Law of P. R. China＂ was promulgated on Oct. 28^th, 2002 and has been put into effect on Sep 1^th, 2003. This paper puts forward some important factors which restrict the development of Strategic Environmental Assessment according to the preliminary practices of SEA in China. These restricting factors are： （1） potential resistance from some departments; （2） poor cooperation between different departments; （3） limited availability of information resources （4） lack of well-developed SEA methods; （5） difficulties in public participation. The primary thought to solve these problems were proposed at policy and technique level.展开更多
Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically...Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.展开更多
For s∈[0,1],b∈R and p∈[1,∞),let˙B_ (p,∞)^(s,b)(R^(n))be the logarithmic-Gagliardo–Lipschitz space,which arises as a limiting interpolation space and coincides to the classical Besov space when b=0 and s∈(0,1)....For s∈[0,1],b∈R and p∈[1,∞),let˙B_ (p,∞)^(s,b)(R^(n))be the logarithmic-Gagliardo–Lipschitz space,which arises as a limiting interpolation space and coincides to the classical Besov space when b=0 and s∈(0,1).In this paper,the authors study restricting principles of the Riesz potential space I_(α)(˙B _(p,∞)^(s,b)(R^(n)))into certain Radon–Campanato space.展开更多
To realize highly sensitive and specific sensing toward sarin,an Eu(III)based metal-organic framework(Eu-CTTB-MOF),encompassing aπ-conjugated organic ligand H4 CTTB(4,4',4'',4'''-(9H-carbazole...To realize highly sensitive and specific sensing toward sarin,an Eu(III)based metal-organic framework(Eu-CTTB-MOF),encompassing aπ-conjugated organic ligand H4 CTTB(4,4',4'',4'''-(9H-carbazole-1,3,6,8-tetrayl)tetrabenzoic acid)was explored for ratiometric fluorescent sensing.An unprecedented specific recognition of nerve-agent sarin mimic diethyl chlorophosphate(DCP)in the presence of HCl interferent and a low limit of detection(LOD,20.97 nM)were achieved.This excellent detection performance is driven by the dual hydrogen bonding and hydrophobic interaction between the CTTB organic ligand and DCP,which would cause a dramatic change in the molecular configuration of the CTTB ligand.Density functional theory(DFT)calculations further verify the recognition of DCP by Eu-CTTB-MOF could suppress the rotations of the aromatic rings in CTTB ligand,significantly reducing the nonradiative decay pathways and subsequently enhancing the fluorescent intensity of the CTTB ligand.Especially,the Eu-CTTB-MOF enables the immediate response to DCP vapor and excellent specificity towards DCP even in the presence of 18 types of interferents,including HCl vapor,structural analogs,and volatile organic solvent,and a gas detector with accurate detection of DCP in simulated scenarios,positioning the designed MOF as a promising sensing material for practical scenarios.We expect that the present sensing strategy will shine a light on the development of brand-new sensing materials for on-site detection applications.展开更多
Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecu...Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.展开更多
BACKGROUND Anxiety and depression are prevalent among patients with chronic heart failure(CHF)and can adversely contribute to treatment adherence and clinical outcomes.Poor fluid restriction adherence is a widespread ...BACKGROUND Anxiety and depression are prevalent among patients with chronic heart failure(CHF)and can adversely contribute to treatment adherence and clinical outcomes.Poor fluid restriction adherence is a widespread challenge in the management of CHF.To effectively manage disease progression and alleviate symptoms,it is crucial to identify key influencing factors to facilitate the implementation of targeted interventions.AIM To investigate the status of anxiety and depression among patients with CHF and determine the factors contributing to poor fluid restriction adherence.METHODS Three hundred CHF patients seeking medical treatment at The First Hospital of Hunan University of Traditional Chinese Medicine between June 2021 and June 2023 were included in the study.Questionnaires,including the Psychosomatic Symptom Scale,Self-Rating Anxiety Scale,Self-Rating Depression Scale,and Fluid Restriction Adherence Questionnaire were administered to patients.Based on their anxiety and depression scores,patients were categorized into anxiety/depression and non-anxiety/depression groups,as well as fluid restriction adherence and fluid restriction non-adherence groups.General patient data were collected,and univariate and logistic regression analyses were conducted to determine the occurrence of depression and anxiety.Logistic regression analysis was used to identify independent factors influencing fluid restriction adherence.RESULTS Statistically significant differences in age,New York Heart Association(NYHA)grading,marital status,educational attainment,and family support were observed between depressed and non-depressed CHF patients(P<0.05).Age,NYHA grading,marital status,educational attainment,and family support were identified as factors influencing the development of depression.The anxiety and non-anxiety groups differed statistically in terms of gender,age,NYHA grading,smoking history,alcohol consumption history,monthly income,educational attainment,and family support(P<0.05).Gender,smoking,alcohol consumption,monthly income,and educational attainment affected anxiety in these patients.The fluid restriction adherence rate was 28.0%,and thirst sensation,anxiety,and depression were identified as independent influencing factors.CONCLUSION CHF patients are susceptible to anxiety and depression,with multiple associated influencing factors.Moreover,anxiety and depression are independent factors that can influence fluid restriction adherence in these patients.展开更多
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ...Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.展开更多
This paper studies evaluation system of restricting factors in training students’ qualities by modern mathematical method of analysis hierarchy process and principal factor analysis, and to build up a mathematical mo...This paper studies evaluation system of restricting factors in training students’ qualities by modern mathematical method of analysis hierarchy process and principal factor analysis, and to build up a mathematical model of evaluation system.展开更多
BACKGROUND Silver-Russell syndrome(SRS)is a clinically heterogeneous entity characterized by intrauterine and postnatal growth restriction,relative macrocephaly at birth,distinct facial features,and body asymmetry com...BACKGROUND Silver-Russell syndrome(SRS)is a clinically heterogeneous entity characterized by intrauterine and postnatal growth restriction,relative macrocephaly at birth,distinct facial features,and body asymmetry combined with other malformations.CASE SUMMARY Herein,we describe four individuals with SRS,focusing on their prenatal phenotype,postnatal presentation,diagnosis,and management.All cases had a typical phenotype,including postnatal growth failure,short stature(chronic malnutrition),and protruding forehead.Individually,they presented with feeding difficulties,leg length discrepancy,triangular face,or relative macrocephaly at birth,and each one exhibited distinct SRS features,including motor and/or speech delay,experiencing frequent hypoglycemic episodes.The fact that each patient exhibited a different combination of clinical findings underlines the heterogeneity of the syndrome.CONCLUSION SRS is diagnosed clinically.However,only 60%of cases are genetically confirmed,while most are sporadic.Although SRS is a well-described syndrome,a delayed diagnosis can have grave consequences on a child’s growth.Recombinant human growth hormone treatment is often initiated shortly after the diagnosis.The follow-up requires a multidisciplinary approach.展开更多
This article is based on a recent bibliometric analysis of research progress on liver aging.The liver is notable for its extraordinary ability to rejuvenate,thereby safeguarding and maintaining the organism’s integri...This article is based on a recent bibliometric analysis of research progress on liver aging.The liver is notable for its extraordinary ability to rejuvenate,thereby safeguarding and maintaining the organism’s integrity.With advancing age,there is a noteworthy reduction in both the liver’s size and blood circulation.Furthermore,the wide range of physiological alterations driven on by aging may foster the development of illnesses.Previous studies indicate that liver aging is linked to impaired lipid metabolism and abnormal gene expression associated with chronic inflammation.Factors such as mitochondrial dysfunction and telomere shortening accumulate,which may result in increased hepatic steatosis,which impacts liver regeneration,metabolism,and other functions.Knowing the structural and functional changes could help elderly adults delay liver aging.Increasing public awareness of anti-aging interventions is essential.Besides the use of dietary supplements,alterations in lifestyle,including changes in dietary habits and physical exercise routines,are the most efficacious means to decelerate the aging process of the liver.This article highlights recent advances in the mechanism research of liver aging and summarizes the promising intervention options to delay liver aging for preventing related diseases.展开更多
The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich inf...The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich information about the surrounding microenvironment.MR methods to measure time-dependent diffusion quantitatively,however,require either non-standard pulse sequences,such as oscillating gradients,or make non-physical assumptions,such as infinitely narrow gradient pulses.Here,we argue that standard spin echo and stimulated echo MR sequences can be used to probe directly.In particular,we propose a framework in which the log-signal ratio obtained from a pair of measurements with different inter-pulse spacingΔis proportional to the MSD between these twoΔvalues along the gradient direction x:-.The framework is quantitative for short,finite-duration gradient pulses and under the Gaussian phase approximation(GPA).To validate the framework,we consider onedimensional diffusion between impermeable,parallel planes,as well as periodicallyspaced,permeable planes.Excellent agreement is obtained between the estimation and the ground truth in the regime where the GPA is expected to hold.Importantly,the GPA can be made to hold for any underlying microstructure,making the proposed framework widely applicable.展开更多
The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phy...The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phytoseidae),the plasticity of life history traits,such as developmental time and size at maturity,is influenced by the quality and quantity of food.This study aimed to investigate the effects of dietary restriction at different life stages(i.e.,juvenile,early adulthood,and later adulthood)on the lifespan and fecundity of P persimilis.We found that reduced dietary intake during early adulthood resulted in a shorter lifespan for both male and female P persimilis.Furthermore,this study demonstrated a sex-specific response to dietary restriction:it extended the lifespan of males but reduced that of females during later adulthood.Diet restriction during the postovipositional period of females showed the most variable life history trait response.Our results showed that the impact of diet restriction at different life stages can have combined influences on the postovipositional duration of P persimilis,where the individuals receiving diet restriction during immature development and early adulthood had a greater reduction in ovipositional duration as those experiencing diet restriction during late adulthood.In addition,we observed a positive correlation between the lifespan and fecundity of females,with higher prey availability increasing both.The insights obtained from our research contribute to a better understanding of the aging process and dietary requirements of P persimilis,which can facilitate the development of more effective biological control strategies using this predator for spider mites in agriculture.展开更多
Under natural conditions, organisms regularly experience seasonal or unpredictable fluctuations in their diet that may shape the quantity and quality of their reproduction. While these dietary shifts are known to infl...Under natural conditions, organisms regularly experience seasonal or unpredictable fluctuations in their diet that may shape the quantity and quality of their reproduction. While these dietary shifts are known to influence overall reproductive output, their specific effects on the proportional composition of egg components remain unexplored. To partially simulate the natural conditions, we conducted two trials using adult Japanese Quails (Coturnix japonica) to examine how dietary restriction and unpredictable feeding influence the proportional composition of egg components. In the first trial, quails were assigned to one of four treatments: full-fed (control) or restricted feeding at 20% (DR20), 30% (DR30), and 40% (DR40) below daily intake. In the second trial, quails were assigned to one of three treatments: full feeding (control), constant 40% restriction (DR40), or unpredictable feeding schedule (UNPR). Each trial lasted for 14 days, and birds were housed individually. Severe dietary restrictions (DR30, DR40) reduced albumen and shell mass, shell thickness, and egg volume. However, yolk mass, yolk color, egg shape index, and shell density remained unaffected across all dietary levels. Severe restrictions also increased the yolk ratio while reducing the albumen ratio, suggesting that birds may evolutionarily prioritize yolk deposition to sustain reproductive functions. However, reduced albumen content due to maternal nutritional stress may also limit essential nutrients, and disrupt the embryo's osmoregulation, which ultimately affects offspring quality. Reduced shell contents at the severe restriction levels can affect the egg's ability to provide physical protection, regulate gas exchange and control water loss, thereby influencing embryonic development. In contrast, moderate restriction (DR20) and unpredictable feeding (UNPR) had no effect on any of the egg traits. These findings suggest that quails strategically allocate resources among egg components under dietary constraints, indicating potential trade-offs in reproductive investment. The resilience observed under moderate restriction and unpredictability underscores the species' adaptive capacity in fluctuating environments.展开更多
Background: Exercise has positive impacts on metabolic health, whereas sleep loss has potentially negative impacts. This systematic literature review investigates whether acute and short-term exercise interventions ca...Background: Exercise has positive impacts on metabolic health, whereas sleep loss has potentially negative impacts. This systematic literature review investigates whether acute and short-term exercise interventions can mitigate negative effects of experimentally-induced sleep loss on metabolic markers in humans.Methods: A systematic search(PubMed/Medline, Web of Science, Scopus, Embase, SPORTDiscus, and Cochrane) following Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines was conducted up to June 2024 for studies that compared glucose and insulin concentrations, insulin sensitivity, skeletal muscle gene expression, and other molecular markers following an acute or short-term(<14 days) exercise intervention during experimentally-induced sleep loss in adult humans. Articles were considered for inclusion and assessed for eligibility using the Population, Intervention, Comparison, Outcomes, and Study design(PICOS) framework, and critically appraised with the Cochrane Risk of Bias 2.0 tool.Results: Of the identified records, 4026 records were screened, with 12 studies meeting all the inclusion criteria and including 177 participants.Sleep intervention varied from a single night of total sleep deprivation to 5 consecutive nights of 4-h sleep opportunity(e.g., early or late sleep restriction), while exercise intervention varied in terms of model(walking/running, cycling, and resistance exercise), volume(e.g., minute to hour), and intensity(e.g., maximum efforts to low-intensity exercise). Most studies indicated a negative effect of insufficient sleep on glucose and insulin concentration as well as mitochondrial adaptations, whereas exercise had a positive impact, mitigating the negative effects on the aforementioned parameters.Conclusion: Exercise is likely to be effective as a therapeutic intervention for mitigating the negative effects of sleep loss on metabolic markers,at least in short-term intervention studies.展开更多
To evaluate the impact of behavioral restrictions on perinatal care caused by the COVID-19 pandemic, we conducted a questionnaire survey of 1976 medical institutions handling deliveries across Japan. The survey examin...To evaluate the impact of behavioral restrictions on perinatal care caused by the COVID-19 pandemic, we conducted a questionnaire survey of 1976 medical institutions handling deliveries across Japan. The survey examined changes in the number of antenatal checkups due to behavioral restrictions, visit restrictions at medical institutions, and the acceptance of COVID-19-infected pregnant and nursing mothers. An increased burden was observed at delivery hospitals, irrespective of whether they accepted infected pregnant and nursing mothers. Some medical institutions were unable to manage infected pregnant women and transferred them to other facilities, highlighting the need for role-sharing among institutions. The number of antenatal checkups showed a decreasing trend, indicating that the pandemic negatively affected checkup attendance. However, no clear increase in perinatal deaths was observed during the observation period, despite the reduction in the number of checkups.展开更多
Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of...Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of compacted sand-bentonite mixtures due to semipermeable membrane behavior has also been demonstrated.However,the extent to which membrane behavior persists in the presence of highly concentrated chemical solutions,which have been shown to degrade membrane behavior in bentonite-based barriers,remains largely unknown.Moreover,the limiting(threshold)salt concentrations at which membrane behavior of compacted sand-bentonite mixtures is effectively destroyed have not been evaluated.Accordingly,this study quantified the limiting membrane behavior of two duplicated specimens of compacted sand-bentonite mixture comprising 15%sodium bentonite(by dry mass)by determining the limiting salt concentrations at which measurable membrane behavior was eliminated.The specimens were exposed to increasingly higher source concentrations,Cot,of boundary monovalent salt solutions(KCl and NaCl)until measured values of the membrane efficiency coefficient,ω,were effectively zero.Overall,ωdecreased from an average of 0.032 to zero as Cot increased from 160 mmol/L KCl to 3.27 mol/L NaCl,resulting in limiting threshold salt concentrations for the two tests between 1.63 mol/L and 3.27 mol/L NaCl,which are significantly higher than those at which measurable membrane behavior has previously been demonstrated.展开更多
Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental grad...Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.展开更多
基金supported by the Postdoctoral Research Funds of Hebei Medical University(30705010016-3759)Natural Science Foundation of China(32272328)+4 种基金Natural Science Foundation of Hebei Province(B2022321001)National Key Research Project of Hebei Province(20375502D)Postdoctoral Research Project of Hebei Province(B2022003031)Science and Technology Research Program of Hebei Provincial Colleges(QN2023229)Hebei Provincial Key Laboratory of Nutrition and Health(2023YDYY-KF05)。
文摘Intermittent fasting can benefit breast cancer patients undergoing chemotherapy or immunotherapy.However,it is still uncertain how to select immunotherapy drugs to combine with intermittent fasting.Herein we observed that two cycles of fasting treatment significantly inhibited breast tumor growth and lung tissue metastasis,as well as prolonged overall survival in mice bearing 4T1 and 4T07 breast cancer.During this process,both the immunosuppressive monocytic-(M-)and granulocytic-(G-)myeloid-derived suppressor cell(MDSC)decreased,accompanied by an increase in interleukin(IL)7R^(+)and granzyme B^(+)T cells in the tumor microenvironment.Interestingly,we observed that Ly6G^(low)G-MDSC sharply decreased after fasting treatment,and the cell surface markers and protein mass spectrometry data showed potential therapeutic targets.Mechanistic investigation revealed that glucose metabolism restriction suppressed the splenic granulocytemonocyte progenitor and the generation of colony-stimulating factors and IL-6,which both contributed to the accumulation of G-MDSC.On the other hand,glucose metabolism restriction can directly induce the apoptosis of Ly6G^(low)G-MDSC,but not Ly6G^(high)subsets.In summary,these results suggest that glucose metabolism restriction induced by fasting treatment attenuates the immune-suppressive milieu and enhances the activation of CD3^(+)T cells,providing potential solutions for enhancing immune-based cancer interventions.
文摘At present, China＇s basic old-age insurance system has been established and develop gradually. To learn advanced endowment service concept and method, meet the demand of higher level of pension services has become the new target and task of the urban pension service system development. The appearance of Wisdom endowment concept is to resolve the diverse endowment risk of the elderly, and meet a higher level elderly pension service demand. However, wisdom pension in our country is still in its infancy, its further development is facing many difficulties. As to these difficulties, the author of this paper will analyze from four aspects, the system, the object, technology, talent, and put forward some suggestions for promoting the development of the wisdom of endowment respectively, and make wise pension industry in China can better meet the diverse needs of the elderly for pension, and construct a harmonious society of＂sense of security＂.
文摘Entrepreneurship quality education is not only the standpoint and focus of entrepreneurship education, but also the key point in entrepreneurship education. In this paper, based on three aspects （the educated, the subjects implementing education, and external environment）, the main factors restricting the entrepreneurship quality education for the young peasant workers back to hometown in Yunnan province are analyzed, and also the governmental strategies of a clear purpose and a powerful applicability are further explored.
文摘＂Environmental Impact Assessment Law of P. R. China＂ was promulgated on Oct. 28^th, 2002 and has been put into effect on Sep 1^th, 2003. This paper puts forward some important factors which restrict the development of Strategic Environmental Assessment according to the preliminary practices of SEA in China. These restricting factors are： （1） potential resistance from some departments; （2） poor cooperation between different departments; （3） limited availability of information resources （4） lack of well-developed SEA methods; （5） difficulties in public participation. The primary thought to solve these problems were proposed at policy and technique level.
文摘Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.
基金Supported by the National Natural Science Foundation of China (Grant No. 12371102)。
文摘For s∈[0,1],b∈R and p∈[1,∞),let˙B_ (p,∞)^(s,b)(R^(n))be the logarithmic-Gagliardo–Lipschitz space,which arises as a limiting interpolation space and coincides to the classical Besov space when b=0 and s∈(0,1).In this paper,the authors study restricting principles of the Riesz potential space I_(α)(˙B _(p,∞)^(s,b)(R^(n)))into certain Radon–Campanato space.
基金supported by the National Key Research and Development Program of China(2022YFA1205500)National Natural Science Foundation of China(22374161)+1 种基金Tianshan Innovation Team Plan(2022TSYCTD0020)the Youth Innovation Promotion Association,CAS(Y2022106).
文摘To realize highly sensitive and specific sensing toward sarin,an Eu(III)based metal-organic framework(Eu-CTTB-MOF),encompassing aπ-conjugated organic ligand H4 CTTB(4,4',4'',4'''-(9H-carbazole-1,3,6,8-tetrayl)tetrabenzoic acid)was explored for ratiometric fluorescent sensing.An unprecedented specific recognition of nerve-agent sarin mimic diethyl chlorophosphate(DCP)in the presence of HCl interferent and a low limit of detection(LOD,20.97 nM)were achieved.This excellent detection performance is driven by the dual hydrogen bonding and hydrophobic interaction between the CTTB organic ligand and DCP,which would cause a dramatic change in the molecular configuration of the CTTB ligand.Density functional theory(DFT)calculations further verify the recognition of DCP by Eu-CTTB-MOF could suppress the rotations of the aromatic rings in CTTB ligand,significantly reducing the nonradiative decay pathways and subsequently enhancing the fluorescent intensity of the CTTB ligand.Especially,the Eu-CTTB-MOF enables the immediate response to DCP vapor and excellent specificity towards DCP even in the presence of 18 types of interferents,including HCl vapor,structural analogs,and volatile organic solvent,and a gas detector with accurate detection of DCP in simulated scenarios,positioning the designed MOF as a promising sensing material for practical scenarios.We expect that the present sensing strategy will shine a light on the development of brand-new sensing materials for on-site detection applications.
基金supported by the Start-up Fund for new faculty from the Hong Kong Polytechnic University(PolyU)(A0043215)(to SA)the General Research Fund and Research Impact Fund from the Hong Kong Research Grants Council(15106018,R5032-18)(to DYT)+1 种基金the Research Center for SHARP Vision in PolyU(P0045843)(to SA)the InnoHK scheme from the Hong Kong Special Administrative Region Government(to DYT).
文摘Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.
基金Huxiang TCM Physique Intervention Clinical Research Center,No.2023SK4061Traditional Chinese Medicine Research Project of Hunan Province,No.B2023065+4 种基金Hunan Province"14th Five-Year Plan"key specialty of TCM,No.[2023]4Hunan University of Chinese Medicine and Hospital Joint Foundation,No.2023XYLH019 and 2024XYLH365R&D Plan for Key Areas of Hunan Provincial Department of Science and Technology,No.2019SK2321Excellent Youth Program of Hunan Education Department,No.24B0346Hunan Provincial Natural Science Foundation for Young Scientists,No.2025JJ60626.
文摘BACKGROUND Anxiety and depression are prevalent among patients with chronic heart failure(CHF)and can adversely contribute to treatment adherence and clinical outcomes.Poor fluid restriction adherence is a widespread challenge in the management of CHF.To effectively manage disease progression and alleviate symptoms,it is crucial to identify key influencing factors to facilitate the implementation of targeted interventions.AIM To investigate the status of anxiety and depression among patients with CHF and determine the factors contributing to poor fluid restriction adherence.METHODS Three hundred CHF patients seeking medical treatment at The First Hospital of Hunan University of Traditional Chinese Medicine between June 2021 and June 2023 were included in the study.Questionnaires,including the Psychosomatic Symptom Scale,Self-Rating Anxiety Scale,Self-Rating Depression Scale,and Fluid Restriction Adherence Questionnaire were administered to patients.Based on their anxiety and depression scores,patients were categorized into anxiety/depression and non-anxiety/depression groups,as well as fluid restriction adherence and fluid restriction non-adherence groups.General patient data were collected,and univariate and logistic regression analyses were conducted to determine the occurrence of depression and anxiety.Logistic regression analysis was used to identify independent factors influencing fluid restriction adherence.RESULTS Statistically significant differences in age,New York Heart Association(NYHA)grading,marital status,educational attainment,and family support were observed between depressed and non-depressed CHF patients(P<0.05).Age,NYHA grading,marital status,educational attainment,and family support were identified as factors influencing the development of depression.The anxiety and non-anxiety groups differed statistically in terms of gender,age,NYHA grading,smoking history,alcohol consumption history,monthly income,educational attainment,and family support(P<0.05).Gender,smoking,alcohol consumption,monthly income,and educational attainment affected anxiety in these patients.The fluid restriction adherence rate was 28.0%,and thirst sensation,anxiety,and depression were identified as independent influencing factors.CONCLUSION CHF patients are susceptible to anxiety and depression,with multiple associated influencing factors.Moreover,anxiety and depression are independent factors that can influence fluid restriction adherence in these patients.
基金supported by the National Natural Science Foundation of China,Nos.82071426,81873784Clinical Cohort Construction Program of Peking University Third Hospital,No.BYSYDL2019002(all to DF)。
文摘Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.
文摘This paper studies evaluation system of restricting factors in training students’ qualities by modern mathematical method of analysis hierarchy process and principal factor analysis, and to build up a mathematical model of evaluation system.
文摘BACKGROUND Silver-Russell syndrome(SRS)is a clinically heterogeneous entity characterized by intrauterine and postnatal growth restriction,relative macrocephaly at birth,distinct facial features,and body asymmetry combined with other malformations.CASE SUMMARY Herein,we describe four individuals with SRS,focusing on their prenatal phenotype,postnatal presentation,diagnosis,and management.All cases had a typical phenotype,including postnatal growth failure,short stature(chronic malnutrition),and protruding forehead.Individually,they presented with feeding difficulties,leg length discrepancy,triangular face,or relative macrocephaly at birth,and each one exhibited distinct SRS features,including motor and/or speech delay,experiencing frequent hypoglycemic episodes.The fact that each patient exhibited a different combination of clinical findings underlines the heterogeneity of the syndrome.CONCLUSION SRS is diagnosed clinically.However,only 60%of cases are genetically confirmed,while most are sporadic.Although SRS is a well-described syndrome,a delayed diagnosis can have grave consequences on a child’s growth.Recombinant human growth hormone treatment is often initiated shortly after the diagnosis.The follow-up requires a multidisciplinary approach.
基金Supported by the National Natural Science Foundation of China,No.82104525Open Foundation of Key Laboratory of Tropical Plant Resource Chemistry of Hainan Province,No.rdzw2024s01.
文摘This article is based on a recent bibliometric analysis of research progress on liver aging.The liver is notable for its extraordinary ability to rejuvenate,thereby safeguarding and maintaining the organism’s integrity.With advancing age,there is a noteworthy reduction in both the liver’s size and blood circulation.Furthermore,the wide range of physiological alterations driven on by aging may foster the development of illnesses.Previous studies indicate that liver aging is linked to impaired lipid metabolism and abnormal gene expression associated with chronic inflammation.Factors such as mitochondrial dysfunction and telomere shortening accumulate,which may result in increased hepatic steatosis,which impacts liver regeneration,metabolism,and other functions.Knowing the structural and functional changes could help elderly adults delay liver aging.Increasing public awareness of anti-aging interventions is essential.Besides the use of dietary supplements,alterations in lifestyle,including changes in dietary habits and physical exercise routines,are the most efficacious means to decelerate the aging process of the liver.This article highlights recent advances in the mechanism research of liver aging and summarizes the promising intervention options to delay liver aging for preventing related diseases.
基金supported by the intramural research program(IRP)of the Eunice Kennedy Shriver National Institute of Child Health and Human Development。
文摘The field of diffusion micro structural magnetic resonance(MR)aims to probe timedependent diffusion,i.e.,an ensemble-averaged mean-squared displacement that is not linear in time.This time-dependence contains rich information about the surrounding microenvironment.MR methods to measure time-dependent diffusion quantitatively,however,require either non-standard pulse sequences,such as oscillating gradients,or make non-physical assumptions,such as infinitely narrow gradient pulses.Here,we argue that standard spin echo and stimulated echo MR sequences can be used to probe directly.In particular,we propose a framework in which the log-signal ratio obtained from a pair of measurements with different inter-pulse spacingΔis proportional to the MSD between these twoΔvalues along the gradient direction x:-.The framework is quantitative for short,finite-duration gradient pulses and under the Gaussian phase approximation(GPA).To validate the framework,we consider onedimensional diffusion between impermeable,parallel planes,as well as periodicallyspaced,permeable planes.Excellent agreement is obtained between the estimation and the ground truth in the regime where the GPA is expected to hold.Importantly,the GPA can be made to hold for any underlying microstructure,making the proposed framework widely applicable.
基金supported in part by New Zealand Government core funding for Crown Research Institutes from the Ministry of Business,Innovation,and Employment's Science and Innovation Group.
文摘The nutritional status of an individual can significantly influence its life history traits,including development,growth,reproduction,and survival.In the predatory mite Phytoseiulus persimilis Athias-Henriot(Acari:Phytoseidae),the plasticity of life history traits,such as developmental time and size at maturity,is influenced by the quality and quantity of food.This study aimed to investigate the effects of dietary restriction at different life stages(i.e.,juvenile,early adulthood,and later adulthood)on the lifespan and fecundity of P persimilis.We found that reduced dietary intake during early adulthood resulted in a shorter lifespan for both male and female P persimilis.Furthermore,this study demonstrated a sex-specific response to dietary restriction:it extended the lifespan of males but reduced that of females during later adulthood.Diet restriction during the postovipositional period of females showed the most variable life history trait response.Our results showed that the impact of diet restriction at different life stages can have combined influences on the postovipositional duration of P persimilis,where the individuals receiving diet restriction during immature development and early adulthood had a greater reduction in ovipositional duration as those experiencing diet restriction during late adulthood.In addition,we observed a positive correlation between the lifespan and fecundity of females,with higher prey availability increasing both.The insights obtained from our research contribute to a better understanding of the aging process and dietary requirements of P persimilis,which can facilitate the development of more effective biological control strategies using this predator for spider mites in agriculture.
基金funded by the National Research, Development and Innovation Office, Hungary (OTKA K139021 to AZL and LC)A Stipendium Hungaricum Scholarship and dissertation scholarship from Tempus Public Foundation
文摘Under natural conditions, organisms regularly experience seasonal or unpredictable fluctuations in their diet that may shape the quantity and quality of their reproduction. While these dietary shifts are known to influence overall reproductive output, their specific effects on the proportional composition of egg components remain unexplored. To partially simulate the natural conditions, we conducted two trials using adult Japanese Quails (Coturnix japonica) to examine how dietary restriction and unpredictable feeding influence the proportional composition of egg components. In the first trial, quails were assigned to one of four treatments: full-fed (control) or restricted feeding at 20% (DR20), 30% (DR30), and 40% (DR40) below daily intake. In the second trial, quails were assigned to one of three treatments: full feeding (control), constant 40% restriction (DR40), or unpredictable feeding schedule (UNPR). Each trial lasted for 14 days, and birds were housed individually. Severe dietary restrictions (DR30, DR40) reduced albumen and shell mass, shell thickness, and egg volume. However, yolk mass, yolk color, egg shape index, and shell density remained unaffected across all dietary levels. Severe restrictions also increased the yolk ratio while reducing the albumen ratio, suggesting that birds may evolutionarily prioritize yolk deposition to sustain reproductive functions. However, reduced albumen content due to maternal nutritional stress may also limit essential nutrients, and disrupt the embryo's osmoregulation, which ultimately affects offspring quality. Reduced shell contents at the severe restriction levels can affect the egg's ability to provide physical protection, regulate gas exchange and control water loss, thereby influencing embryonic development. In contrast, moderate restriction (DR20) and unpredictable feeding (UNPR) had no effect on any of the egg traits. These findings suggest that quails strategically allocate resources among egg components under dietary constraints, indicating potential trade-offs in reproductive investment. The resilience observed under moderate restriction and unpredictability underscores the species' adaptive capacity in fluctuating environments.
文摘Background: Exercise has positive impacts on metabolic health, whereas sleep loss has potentially negative impacts. This systematic literature review investigates whether acute and short-term exercise interventions can mitigate negative effects of experimentally-induced sleep loss on metabolic markers in humans.Methods: A systematic search(PubMed/Medline, Web of Science, Scopus, Embase, SPORTDiscus, and Cochrane) following Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines was conducted up to June 2024 for studies that compared glucose and insulin concentrations, insulin sensitivity, skeletal muscle gene expression, and other molecular markers following an acute or short-term(<14 days) exercise intervention during experimentally-induced sleep loss in adult humans. Articles were considered for inclusion and assessed for eligibility using the Population, Intervention, Comparison, Outcomes, and Study design(PICOS) framework, and critically appraised with the Cochrane Risk of Bias 2.0 tool.Results: Of the identified records, 4026 records were screened, with 12 studies meeting all the inclusion criteria and including 177 participants.Sleep intervention varied from a single night of total sleep deprivation to 5 consecutive nights of 4-h sleep opportunity(e.g., early or late sleep restriction), while exercise intervention varied in terms of model(walking/running, cycling, and resistance exercise), volume(e.g., minute to hour), and intensity(e.g., maximum efforts to low-intensity exercise). Most studies indicated a negative effect of insufficient sleep on glucose and insulin concentration as well as mitochondrial adaptations, whereas exercise had a positive impact, mitigating the negative effects on the aforementioned parameters.Conclusion: Exercise is likely to be effective as a therapeutic intervention for mitigating the negative effects of sleep loss on metabolic markers,at least in short-term intervention studies.
文摘To evaluate the impact of behavioral restrictions on perinatal care caused by the COVID-19 pandemic, we conducted a questionnaire survey of 1976 medical institutions handling deliveries across Japan. The survey examined changes in the number of antenatal checkups due to behavioral restrictions, visit restrictions at medical institutions, and the acceptance of COVID-19-infected pregnant and nursing mothers. An increased burden was observed at delivery hospitals, irrespective of whether they accepted infected pregnant and nursing mothers. Some medical institutions were unable to manage infected pregnant women and transferred them to other facilities, highlighting the need for role-sharing among institutions. The number of antenatal checkups showed a decreasing trend, indicating that the pandemic negatively affected checkup attendance. However, no clear increase in perinatal deaths was observed during the observation period, despite the reduction in the number of checkups.
文摘Compacted sand-bentonite mixtures are used as waste containment barriers(e.g.landfill liners and bentonite buffers for nuclear waste)to restrict contaminant transport.The potential for enhanced chemical containment of compacted sand-bentonite mixtures due to semipermeable membrane behavior has also been demonstrated.However,the extent to which membrane behavior persists in the presence of highly concentrated chemical solutions,which have been shown to degrade membrane behavior in bentonite-based barriers,remains largely unknown.Moreover,the limiting(threshold)salt concentrations at which membrane behavior of compacted sand-bentonite mixtures is effectively destroyed have not been evaluated.Accordingly,this study quantified the limiting membrane behavior of two duplicated specimens of compacted sand-bentonite mixture comprising 15%sodium bentonite(by dry mass)by determining the limiting salt concentrations at which measurable membrane behavior was eliminated.The specimens were exposed to increasingly higher source concentrations,Cot,of boundary monovalent salt solutions(KCl and NaCl)until measured values of the membrane efficiency coefficient,ω,were effectively zero.Overall,ωdecreased from an average of 0.032 to zero as Cot increased from 160 mmol/L KCl to 3.27 mol/L NaCl,resulting in limiting threshold salt concentrations for the two tests between 1.63 mol/L and 3.27 mol/L NaCl,which are significantly higher than those at which measurable membrane behavior has previously been demonstrated.
基金funded by the Empresas Públicas de Medellín and Universidad de Antioquia.
文摘Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors (TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.
