Duration Of Reproductive Period Research Articles

Reproductive period duration and cognitive function in postmenopausal Latina women in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

A shorter reproductive period, a marker of estrogen exposure, has been related to cognitive impairment among older (>65years) non-Hispanic White women. We explored whether reproductive period duration, age at menarche, and age at menopause are related to cognitive function among postmenopausal Hispanic/Latina women. This cross-sectional analysis used baseline (Visit 1: 2008-2011) data from 3630 postmenopausal women in the Hispanic Community Health Study/Study of Latinos. Reproductive period duration, age at menarche, and age at menopause were assessed by self-report. Cognitive function variables included global cognition, verbal learning, memory, verbal fluency, and processing speed. Associations between each reproductive event and cognitive function were examined using multivariable linear and logistic regression analyses accounting for the complex survey design of the study and adjusting for socio-demographics, parity, and cardiovascular risk factors. We assessed whether associations differed by type of menopause (natural versus surgical) and hormone therapy use. The study population was on average aged 59years, with a mean reproductive period duration of 35years. Older age at menopause and a longer reproductive period were related to higher verbal learning (β=0.04, SE=0.02; p<0.05) and processing speed (ß=0.16, SE=0.04; p<0.001); associations were more pronounced for women with natural menopause. Older age at menarche was associated with lower scores on the digit symbol substitution test (ß=-0.62, SE=0.15; p<0.0001). There were no associations with global cognition. Among postmenopausal Hispanic/Latinas, a longer reproductive period was related to more favorable cognitive measures of verbal learning and processing speed. Our findings support the hypothesis that greater lifetime exposure to estrogens may be associated with higher cognitive performance.

Age-related dynamics of reproductive activity and physical conditions in Cricetidae of different ecological speciation (Rodentia)

To understand the evolutionary preconditions of extended longevity, one can compare the key life-history events and age related changes in body conditions in related species with different ecological speciation. Cricetid rodents possessing a wide spectrum of adaptive forms with different life history strategies are an excellent model for this purpose. We compared median and maximum longevity, life expectancy, temporal distribution of reproductive efforts, and age related dynamic of several physical condition indexes: body mass, muscle strength, locomotor activity and frequency of vertical postures in open field tests in five species of this family. Studied species vary both in maximum (from three years in steppe lemmings (Lagurus lagurus) to more than six years in mole voles (Ellobius talpinus) and rock voles (Alticola strelzovi) and median longevity (from less than one year in Lagurus lagurus to 2.8 years in rock vole Alticola tuvinicus). Both species with high maximum longevity – Ellobius talpinus and Alticola strelzovi face chronic hypoxia in their native environment. The total amount of litters born varied from three in A. strelzovi to 13 in Phodopus sungorus. Species under study also differed in age-related dynamics of physical conditions. Among the studied species, the subterranean E. talpinus has the highest maximum longevity with relatively long duration of reproductive period and only weak age-related deterioration in body conditions, i.e. shares many aspects of the life history strategy of such a specialized group as the Bathyergidae family.

Mutant Tof11 alleles are highly accumulated in early planting-adaptable Japanese summer type soybeans.

To avoid crop failure because of climate change, soybean (Glycine max (L.) Merrill) cultivars adaptable to early planting are required in western Japan. Because current Japanese cultivars may not be adaptable, genetic resources with high early-planting adaptability, and their genetic information must be developed. In the present study, summer type (ST) soybeans developed for early planting were used as plant materials. We examined their phenological characteristics and short reproductive period as an indicator of early planting adaptability and performed genetic studies. Biparental quantitative trait loci (QTL) analysis of a representative ST cultivar revealed a principal QTL for the reproductive period duration on chromosome 11. The results of resequencing analysis suggested that circadian clock-related Tof11 (soybean orthologue of PRR3) is a candidate QTL. Additionally, all 25 early planting-adaptable germplasms evaluated in this study possessed mutant alleles in Tof11, whereas 15 conventional cultivars only had wild-type alleles. These results suggest that mutant alleles in Tof11 are important genetic factors in the high adaptability to early planting of these soybeans, and thus, these alleles were acquired and accumulated in the ST soybean population.

Maximization of fitness by phenological and phenotypic plasticity in range expanding rabbitfishes (Siganidae).

Global warming is modifying the phenology, life‐history traits and biogeography of species around the world. Evidence of these effects have increased over recent decades; however, we still have a poor understanding of the possible outcomes of their interplay across global climatic gradients, hindering our ability to accurately predict the consequences of climate change in populations and ecosystems.We examined the effect that changes in biogeography can have on the life‐history traits of two of the most successful range‐extending fish species in the world: the tropical rabbitfishes Siganus fuscescens and Siganus rivulatus. Both species have established abundant populations at higher latitudes in the northern and southern hemispheres and have been identified as important ecological engineers with the potential to alter the community structure of seaweed forests (Laminariales and Fucales) in temperate regions.Life‐history trait information from across their global distribution was compiled from the published literature and meta‐analyses were conducted to assess changes in (i) the onset and duration of reproductive periods, (ii) size at maturity, (iii) fecundity, (iv) growth rates, (v) maximum body sizes and (vi) longevity in populations at the leading edge of range expansion in relation to sea surface temperature and primary productivity (a common proxy for nutritional resource levels).Populations at highest latitudes had shortened their reproductive periods and reduced growth rates, taking longer to reach sexual maturity and maximum sizes, but compensated this with higher fecundity per length class and longer lifespans than populations in warmer environments. Low primary productivity and temperature in the Mediterranean Sea resulted in lower growth rates and body sizes for S. rivulatus, but also lower length at maturity, increasing life‐time reproductive output.The results suggest that plasticity in the phenology and life‐history traits of range‐expanding species would be important to enhance their fitness in high latitude environments, facilitating their persistence and possible further poleward expansions. Quantifying the magnitude and direction of these responses can improve our understanding and ability to forecast species redistributions and its repercussions in the functioning of temperate ecosystems.

Duration of Reproductive Period and Risk of Transitioning to Mild Cognitive Impairment and Dementia

Decreasing estrogen levels have been hypothesized to be associated with increased risk of dementia, yet the current literature reveals conflicting results. This study aimed to determine whether a longer reproductive period, as an indicator of longer exposure to endogenous estrogens, is associated with risk of transitioning to MCI and dementia. Women 65 and over (N=1507) from the Rush Memory and Aging Project met eligibility for the current analysis. The average length of reproductive period (menopause age minus menarche age) was 35 years (range=16-68 years), and 64% had natural menopause. Multistate survival modeling (MSM) was used to estimate the influence of reproductive period on risk of transitioning through cognitive states including mild cognitive impairment (MCI) and clinically diagnosed dementia, as well as death. Multinomial regression models estimated total and cognitively unimpaired life expectancies based on the transition probabilities estimated by the MSM. Results suggest that women with more reproductive years were less likely to transition from no cognitive impairment (NCI) to MCI, and were more likely to return to NCI from MCI. Analyses also suggest two additional years free of cognitive impairment for women with 45 vs 25 years of reproduction, though reproduction period did not significantly impact overall life expectancy. This study suggests that the number of years of reproductive duration is not associated with the transition to dementia, but is possibly associated with delayed cognitive decline, reduced risk of MCI, increased likelihood of returning to NCI from MCI, and increased lifespan free of cognitive impairment.

Timing Is Everything. Temporal and Spatial Niche Segregation in Curculio spp. (Coleoptera: Curculionidae) Associated with Oak Trees.

Simple SummaryAcorn weevils from the genus Curculio (Curculionini) represent a group of species developing in fructifications of plants. In Poland, three different species of those beetles develop on the same host plant and use the same resources, which can lead to increased competition. We tested preferences of weevil females towards acorn size chosen for oviposition as well as reproduction time and other characteristics of their breeding behavior. The results clearly indicate that particular species prefer acorns of different masses and breeds in different periods corresponding to different stages of fruit growth. In other words, this enables weevils to pass each other during reproduction. Furthermore, one of the studied species varies distinctly also in terms of the number of laid eggs and the manner of locating them within the acorn tissues. Our observations support the hypothesis that niche partitioning among the species appears to be occurring when the resources—acorns, are limited. The work helps to understand how multi-species communities of insects cope in order to survive in a shared habitat.Oak seed predatory weevils occurring in Poland are prone to increased interspecific competition due to the limited number of Quercus species, compared to southern Europe, in which they can develop. Therefore, analyses on the preferences of three weevil species for acorn sizes chosen for reproduction, as well as on reproductive period duration, were performed. Cafeteria-type experiments were set for females of three species associated with one oak species. Females were allowed to choose and oviposit in acorns of different sizes and growth stages. Research revealed statistically significant differences between the masses of acorns chosen for oviposition by females of Curculio glandium (the biggest), C. pellitus (medium), and C. venosus (the smallest). Studied weevils also differed in terms of the beginning of the reproductive period, which corresponded with the increasing mass of growing acorns. Moreover, C. glandium was observed to be the only species to perform radial egg galleries and lay a considerably higher and varied number of eggs. The results support the hypothesis of a strategy aimed at reducing interspecific competition between Curculio spp. in terms of limited host plant species number.

Transcriptomic analysis reveals the inhibition of reproduction in rice brown planthopper, Nilaparvata lugens, after silencing the gene of MagR (IscA1).

MagR (IscA1) is a member of the iron-sulphur cluster assembly proteins, which plays vital roles in many physiological processes, such as energy metabolism, electron transfer, iron homeostasis, heme biosynthesis and physiologically magnetic response. Its deletion leads to the loss of mitochondrial DNA, inactivation of iron-sulphur proteins and abnormal embryonic development in organisms. However, the physiological roles of MagR in insects are unclear. This study characterized the effects and molecular regulatory mechanism of MagR gene silencing on the reproduction of brachypterous female adults of Nilaparvata lugens. After silencing the MagR gene using RNAi approach, the duration of reproductive period was shortened and the fecundity and hatchability reduced significantly. A total of 479 differentially expressed genes (DEGs) were identified for female adults after 2 days of dsRNA injection through RNA-sequencing technology, including 352 significantly upregulated DEGs and 127 significantly downregulated DEGs, among which 44 DEGs were considered the key genes involved in the effects of NlMagR silencing on the reproduction, revealing the regulatory mechanism of MagR at RNA transcription level and providing a new strategy for the control of N. lugens.

Variation in susceptibility of rapeseed cultivars to the peach potato aphid

Considering the need for reduction in insecticide use, we studied the potential for antibiosis and the potential for antixenosis in seven highly yielding winter Brassica napus L. cultivars against Myzus persicae (Sulz.). We found evidence for antixenosis, i.e., disruption in probing in non-phloem tissues and a failure in reaching sieve elements in cultivar ‘Alister’. We found evidence for antibiosis, i.e., reduced ability of the plant to serve as a host, in cultivar ‘Florida’. On ‘Alister’ and ‘Florida’, net reproduction and reproductive period duration of M. persicae were the lowest of all studied cultivars. ‘Adriana’, ‘Andromeda’, ‘Gladius’, and ‘Kolumb’ are intermediately susceptible to M. persicae infestation with medium values of net reproduction and reproduction period duration, and slight disturbances in aphid probing and feeding. ‘Artoga’ is highly susceptible. On ‘Artoga’, reproduction period was the longest, daily fecundity and net reproduction of M. persicae were highest, and probing and feeding behaviors were unaltered. Glucoallysin, glucobrassicanapin, gluconapin, gluconapoliferin, progoitrin, glucobrassicin, and 4-OH-glucobrassicin occurred in the leaves of all rapeseed cultivars in similar quantities and proportions and did not affect aphid performance and phloem sap ingestion by M. persicae.

Bone marrow adiposity is inversely associated with bone mineral density in postmenopausal females.

Aim To evaluate vertebral bone marrow adiposity (BMA) using magnetic resonance spectroscopy (MRS) in postmenopausal women and to determine an association of bone density with bone marrow fat content. Methods This cross-sectional study included 120 postmenopausal women referred for osteoporosis screening. All women underwent assessment of bone mineral density by dual X-ray absorptiometry (DXA), who were divided based on T scores into osteoporosis (OST; n=60) and control group (CG; n=60). MRS was used to measure fat fraction (FF), lipid/water ratio (LWR) and fat content (FC) at vertebral spine (L1-L4). Results Mean age, menopause or reproductive period duration was not significantly different between women in OST and control group. Median LWR in OST group was significantly higher compared to CG, 31.5 (22.9-38.8) vs. 28.7 (13.7-37.3) (p=0.039). Median FC was significantly higher in OST compared to the control group, 47.0 (46.3-78.8) and 46.4 (44.3-48.6), respectively (p=0.011). FC was significantly negatively associated with BMD at lumbar spine (Rho=-0.042; p<0.001) and with BMD at hip (Rho=-0.64; p<0.001). In logistic regression model, FC remained independently associated with osteoporosis after controlling for confounders (age, menopause duration, reproductive period duration and body mass index) (OR=1.3; 95% CI 1.1-1.6). Conclusion Bone marrow adiposity is an independent predictor of low bone mass in postmenopausal women suggesting its role as a therapeutic target in postmenopausal osteoporosis management.

Life-long endogenous estrogen exposure is associated with prevalence of allergic rhinitis in postmenopausal women.

The aim of the study was to investigate the influence of life-long endogenous estrogen exposure on prevalence of chronic rhinitis including allergic rhinitis (AR) in the postmenopausal period. In this cross-sectional study, a total of 3,043 postmenopausal women who participated in the Korea National Health and Nutrition Examination Survey V were included. Participants with symptoms including sneezing, rhinorrhea, nasal obstruction, or nasal itching were considered to have chronic rhinitis. In subgroup analysis, the AR group comprised participants with rhinitis with positive findings in at least one of three specific immunoglobulin E. Univariable and multivariable logistic analyses were performed to evaluate the relationship between rhinitis and estrogen-related factors including age at menarche, age at menopause, age at first delivery, parity, and duration of breast-feeding. Participants with chronic rhinitis (17.6%) had higher parity (odd ratio [OR] = 1.17, P = 0.0135) and shorter duration of breast-feeding (OR = 0.98, P = 0.0388) than controls. In subgroup analysis, participants with AR (7.1%) had younger age at menarche (OR = 0.56, P = 0.0028) and older age at menopause (OR = 1.42, P = 0.0060) after adjustment of confounding factors. There was a positive association between age at menopause and specific immunoglobulin E for both cockroach (OR = 1.38, P = 0.0132) and dogs (OR = 1.38, P = 0.0302). Longer postmenopausal duration was positively associated with cockroach allergen sensitization (OR = 1.25, P = 0.201). Longer duration of reproductive period was associated with higher prevalence of AR and aeroallergen sensitization in the postmenopausal period. Moreover, cockroach allergen sensitization was associated with a longer postmenopausal period.

Intraspecific morphological variation of the sperm storing organ in two hermaphroditic land snail species

BackgroundPostcopulatory sexual selection is very important in species with reproductive strategies that involve multiple mating and prolonged sperm storage. The sperm storage organ has been hypothesized to evolve in response to different levels of sperm competition in several species while population density has been considered as a factor that approximates sperm competition risk and intensity in the field. Apart from population density, local microclimatic conditions may also play a role in determining sperm competition levels in natural populations of land snails by affecting their chances of encountering mates. The goal of this study was to investigate the variation of the structure of the sperm storage organ in the simultaneously hermaphroditic land snails Helix lucorum and Cepaea vindobonensis occurring sympatrically in two sites which differed in habitat humidity. The populations of both species from the two sites, also differed in density and in duration of reproductive period. Multiple samples were taken from each population in order to test for temporal variation.ResultsIn both species, the spermatheca consisted of a simple fertilization chamber and a variable number of lateral tubules. The length of the spermatheca showed no temporal or spatial differentiation nor did it show any correlation with snail size. The number of tubules in Helix lucorum ranged from five to sixteen and in Cepaea vindobonensis from one to eight and in both species a significant difference of this trait between the two study sites was detected. In Cepaea vindobonensis, the difference in tubule number led to difference of the total tubule length which reflects sperm storage capacity of the spermatheca but this was not the case with H. lucorum in which no increase in total tubule length was detected.ConclusionsIntraspecific variation in the spermatheca was observed in both snail species studied. The variation observed was independent of snail size, and reproduction status, while the two species responded differently to higher sperm competition levels.

Effects of reproductive period duration and number of pregnancies on midlife ECG indices: a secondary analysis from the Women’s Health Initiative Clinical Trial

ObjectivesPregnancy, menses and menopause are related to fluctuations in endogenous sex hormones in women, which cumulatively may alter cardiac electrical conduction. Therefore, we sought to study the association between number...

The relation of age at menarche with age at natural menopause: a population study of 336 788 women in Norway.

STUDY QUESTIONIs age at menarche associated with age at menopause or with duration of the reproductive period (interval between menarche and menopause)?SUMMARY ANSWERThe association of age at menarche with age at menopause was weak and non-linear, and the duration of the reproductive period decreased by increasing age at menarche.WHAT IS KNOWN ALREADYIt remains uncertain whether age at menarche is associated with age at menopause. Some studies report that women with early menarche also have early menopause. Other studies report that women with early menarche have late menopause, or they report no association. The duration of the reproductive period may be an indicator of the cumulative endogenous exposure to estrogens and progestogens during life course and is associated with risk of breast cancer and endometrial cancer.STUDY DESIGN, SIZE, DURATIONA retrospective cohort study of 336 788 women, aged 48–71 years, in the BreastScreen Norway during the years 2006–2014 was performed.PARTICIPANTS/MATERIALS, SETTING, METHODSInformation about age at menarche and menopausal status was obtained by self-administered questionnaires. We used time to event approaches to estimate the associations.MAIN RESULTS AND THE ROLE OF CHANCEMedian age at menopause was 51 years in most menarche groups. Women with menarche at age 16 years or age ≥ 17 years had menopause 1 year later [median: 52 years, interquartile range (IQR): 49–54 years] than women with menarche at age 13 years (median: 51 years, IQR: 49–54 years, reference) (crude hazard ratio (HR) = 0.95; 95% CI: 0.93–0.97 and 0.95; 95% CI: 0.92–0.99, Pnon-linearity < 0.001). The reproductive period decreased with increasing age at menarche (Pnon-linearity < 0.001), and women with menarche at age ≤ 9 years had 9 years longer median reproductive period than women with menarche at age ≥ 17 years (median: 43 versus 34 years). Adjustment for year of birth did not change the HR estimates notably.LARGE SCALE DATANot applicable.LIMITATIONS, REASONS FOR CAUTIONInformation about age at menarche and age at menopause was based on self-reports. Particularly for age at menarche, the long time interval between the event and data collection may have caused imprecise reporting.WIDER IMPLICATIONS OF THE FINDINGSOur study suggests that age at menarche is a strong indicator for the duration of women’s reproductive period. Our findings should encourage studies of the independent role of duration of the reproductive period on the risk of breast cancer and endometrial cancer, since these cancers have been associated with exposure to estrogens and progestogens.STUDY FUNDING/COMPETING INTEREST(S)The present study was funded by the Norwegian Cancer Society [Grant number 6863294-2015]. The authors declare no conflicts of interest.

Многолетняя динамика репродуктивных показателей европейского анчоуса Engraulis encrasicolus (L., 1758) и их связь с температурными условиями

Европейский анчоус, или хамса (Engraulis encrasicolus L.), — один из наиболее массовых видов рыб в Азово-Черноморском бассейне. Является основным промысловым объектом: доля его вылова составляет около 80 %. Оценка состояния популяции хамсы и её динамики в условиях климатического потепления — одна из актуальных задач современных исследований. Данная статья посвящена изучению многолетней динамики ряда популяционных репродуктивных показателей хамсы и их связи с температурой воды с целью возможного использования для прогноза состояния популяции при изменении условий среды. В основе работы – полученные в 2000–2015 гг. результаты собственных исследований, выполненных в прибрежной акватории Чёрного моря, прилегающей к юго-западному побережью Крыма (район Севастополя — Балаклавы). Для сбора икры хамсы использовали планктонную сеть Богорова — Расса (БР-80/113) в режиме вертикального лова в слое 0–10 м. Взрослые экземпляры получены из ставных неводов. Проанализированы 702 ихтиопланктонные пробы и 941 экз. нерестовых самок (на стадиях зрелости V, VI–IV и VI–V). Среди популяционных репродуктивных показателей были изучены календарные сроки и продолжительность нерестового периода, интенсивность и эффективность нереста, внутривидовой состав родительского стада. Календарные сроки нереста хамсы в 2000–2014 гг. у юго-западного побережья Крыма варьировали от второй декады мая (ранний нерест) до третьей декады июня (поздний нерест); сроки окончания — от третьей декады августа до третьей декады сентября. Общая продолжительность репродуктивного периода составляла 8–14 недель, средняя — 11 недель. В многолетнем плане установлен сдвиг начала нереста на более ранние календарные сроки. Максимальные (пиковые) среднемесячные значения интенсивности нереста в 2012–2013 гг. варьировали от 33.6 до 78.7 % (среднее 51.2 %). Пик популяционного нереста приходится на июль и август; его повторяемость в июле составила 25.0 %, в августе — 66.7 %. В многолетнем плане установлен сдвиг пика нереста на более ранние сроки: в 2000–2005 гг. повторяемость пика нереста в августе составляла 100 %, в 2007–2013 гг. — только 50 %. Абсолютная численность икры (эффективность нереста) в 2000–2014 гг. изменялась от 1.6 до 29.9 экз.·м-2, составив в среднем 10.3 экз.·м-2. Условно выделены низко-, средне- и высокоурожайные годы с численностью икры менее 10, 10–20 и более 20 экз.·м-2 соответственно и со средней эффективностью нереста 5.1, 14.5 и 25.0 экз.·м-2. Эффективность нереста высокоурожайных лет в 1.7 и 4.9 раза превышает таковую средне- и низкоурожайных лет. Установлен многолетний положительный тренд эффективности нереста. В 2000–2011 гг. произошла перестройка внутривидовой структуры хамсы, которая сопровождалась перераспределением численного соотношения в составе нерестовой части популяции представителей азовского и черноморского подвидов в пользу последнего. До 2004 г. относительная численность черноморской хамсы составляла 33.3 %, после 2004 г. — 76.7 %. Одновременно произошло заметное увеличение её вылова. Коэффициент корреляции между относительной численностью черноморской хамсы и выловом составил 0.92. Календарные сроки начала нереста, его интенсивность и эффективность тесно связаны с температурой воды. Нижней температурной границей массового нереста является 17.5 °С. Область «максимально благоприятной нерестовой температуры» находится выше 23 °С. В её пределах реализуется около 2/3 репродуктивного потенциала популяции.

Age at menopause and duration of reproductive period in association with dementia and cognitive function: A systematic review and meta-analysis

IntroductionThe preponderance of dementia among postmenopausal women compared with same-age men and the female sex hormones neuroprotective properties support a tentative role of their deficiency in the dementia pathogenesis. MethodsPairs of independent reviewers screened 12,323 publications derived from a search strategy for MEDLINE to identify articles investigating the association of age at menopause/reproductive period with (i) dementia and (ii) cognitive function; a snowball of eligible articles and reviews was conducted and authors were contacted for additional information. Random-effect models were used for the meta-analysis. ResultsAge at menopause (13 studies; 19,449 participants) and reproductive period (4 studies; 9916 participants) in the highest categories were not associated with odds of dementia (effect size [ES]: 0.97 [0.78–1.21]) and Alzheimer’s disease (ES: 1.06 [0.71–1.58]). Significant heterogeneity was however noted in both analyses (I2: 63.3%, p=0.003 and I2: 72.6%, p=0.01, respectively). Subgroup analyses by outcome assessment, study design, level of adjustment and study quality did not materially change the findings. In 9/13 studies assessing cognitive function, advanced age at menopause/longer reproductive period was significantly associated with better cognitive performance/lower decline. Due to statistical differences, no meta-analysis was possible for cognitive function. ConclusionsExisting evidence does not support an association between indices of prolonged exposure to female hormones and lower dementia risk. There are indications, however, for better cognitive performance and delayed cognitive decline, supporting a link between female hormone deficiency and cognitive aging. Current literature limitations, indicated by the heterogeneous study-set, point towards research priorities in this clinically relevant area.

Does menopausal transition really influence mental health? Findings from the prospective long-term Zurich study.

In the prospective long-term Zurich study, we re-examined the hypothesized association between mental health problems in women and the transition through menopausal stages. One hundred sixty-eight women from a population-based Swiss community cohort were prospectively followed up from age 21 to 50. At age 50, the occurrence of hot flushes/night sweats and sleep disturbances was significantly more frequent in peri- and post-menopausal women. Irritability/nervousness was increased only in peri-menopausal women, but that association was accounted for by neuroticism trait scores at age 30. Transitions to peri- or post-menopause were not related to changes in either the prevalence rates of DSM major depressive episode or anxiety disorders, or the course of psychopathological syndromes as assessed by the Symptom Checklist 90 - Revised. The null associations held when adjusting for duration of reproductive period or age at menopause. Preceding mental health problems between ages 21 and 41, increased neuroticism trait scores at age 30, and concurrent psychosocial distress were significantly related to mental health problems occurring between ages 41 and 50. Depending upon the cut-off point that was chosen, the arbitrary dichotomization of a continuous depression outcome produced spurious associations with the menopausal transition. We conclude that mental health problems between ages 41 and 50 are probably not directly related to the menopausal transition, and that previously reported associations could be false positives due to inadequate dichotomizations, reporting bias, undisclosed multiple adjustments or overfitting.

Association of Age at Menopause and Duration of Reproductive Period With Depression After Menopause: A Systematic Review and Meta-analysis.

Estrogens have neuroprotective and antidepressive effects; however, associations between indices of reduced endogenous estrogens and risk for postmenopausal depression have not been systematically explored. To investigate the association of age at menopause and the duration of the reproductive period with the risk for depression among postmenopausal women with naturally occurring menopause. A search strategy for use of MEDLINE was developed (through January 1, 2015) using the key terms menopause, climacteric, reproductive period, depression, and mood disorders. References of included studies and reviews were also screened; authors were contacted to maximize synthesized evidence. A total of 12,323 articles, without language restriction, were screened by pairs of reviewers to identify observational studies related to the study hypothesis; 14 studies were eligible for meta-analysis. Pairs of reviewers independently extracted information on study design and type of analysis by participants' characteristics and methods of depression ascertainment. Study quality was assessed using the Newcastle-Ottawa Scale, and fixed- or random-effects models were implemented. Pooled-effect estimates for depression, defined by psychiatric evaluation or validated instruments, by age at menopause and duration of the reproductive period. The 14 studies included in the meta-analysis represented 67,714 women. An inverse association (reported as odds ratio [OR]; 95% CI of 2-year increments) with depression in postmenopausal women was shown for increasing age at menopause (0.98; 0.96-0.99 [67,434 unique participants; 13 studies]) and duration of the reproductive period (0.98; 0.96-0.99 [54,715 unique participants; 5 studies]). Menopause at age 40 or more years compared with premature menopause was associated with a 50% decreased risk for depression (3033 unique participants; 4 studies). Pooling of studies examining severe depression showed a 5% decrease in risk of severe depression with increasing (2-year increment) age at menopause (52,736 unique participants; 3 studies); sensitivity analysis of studies controlling for past depression revealed similar results for age at menopause (0.98; 0.96-1.00 [48,894 unique participants; 3 studies). No heterogeneity or publication bias was evident in the main analyses. Longer exposure to endogenous estrogens, expressed as older age at menopause and longer reproductive period, is associated with a lower risk of depression in later life. Identifying women at higher risk for depression due to early menopause who could benefit from psychiatric intervention or estrogen-based therapies could be useful in the clinical setting.

Darwin was right: inbreeding depression on male fertility in the Darwin family

Charles Darwin, who was married to his first cousin Emma Wedgwood, was the first experimentalist to demonstrate the adverse effects of inbreeding. He documented the deleterious consequences of self-fertilization on progeny in numerous plant species, and this research led him to suspect that the health problems of his 10 children, who were very often ill, might have been a consequence of his marriage to his first cousin. Because Darwin's concerns regarding the consequences of cousin marriage on his children even nowadays are considered controversial, we analyzed the potential effects of inbreeding on fertility in 30 marriages of the Darwin-Wedgwood dynasty, including the marriages of Darwin's children, which correspond to the offspring of four cousin marriages and three marriages between unrelated individuals. Analysis of the number of children per woman through zero-inflated regression models showed a significantly adverse effect of the husband inbreeding coefficient on family size. Furthermore, a statistically significant adverse effect of the husband inbreeding coefficient on reproductive period duration was also detected. To our knowledge, this is the first time that inbreeding depression on male fertility has been detected in humans. Because Darwin's sons had fewer children in comparison to non-inbred men of the dynasty, our findings give empirical support to Darwin's concerns on the consequences of consanguineous marriage in his own progeny.

Plant phenology as affected by land degradation in the arid Patagonian Monte, Argentina: A multivariate approach

In recent years, there has been an increasing interest in the study of climate change effects on plant phenology. However, the effects of other more localized components of global change such as land degradation have been almost completely ignored. In this paper we evaluate the phenological patterns of 10 plant species at three sites with contrasting levels of land degradation due to overgrazing in the Patagonian Monte, Argentina, and their relationship with plant morphology, browsing intensity, and plant competition.Plant phenology differed among sites in eight species, but plant responses were species-specific. In six species the dormancy and senescence periods were shorter indicating longer growing cycles at high degradation than at low degradation site. Generally, plants growing at high degradation site present longer and frequently incomplete vegetative periods and shorter and less dominant reproductive periods than those at low degradation site. However, in some species the duration of reproductive periods was greater in the high degradation site. Plant size (i.e. height, area, and/or internal cover) affected plant phenology in seven species. In contrast, browsing and neighbor's cover were rarely related to plant phenology. Our results suggest that other global change components such as land degradation may affect plant phenology.

Climate change, wheat productivity and water use in the North China Plain: A new super-ensemble-based probabilistic projection

Ensemble-based probabilistic projection is an effective approach to deal with the uncertainties in climate change impact assessments and to inform adaptations. Here, the crop model MCWLA-Wheat was firstly developed by adapting the process-based general crop model, MCWLA [Tao, F., Yokozawa, M., Zhang, Z., 2009a. Modelling the impacts of weather and climate variability on crop productivity over a large area: a new process-based model development, optimization, and uncertainties analysis. Agric. For. Meteorol. 149, 831–850], to winter wheat. Then the Bayesian probability inversion and a Markov chain Monte Carlo (MCMC) technique were applied to the MCWLA-Wheat to analyse uncertainties in parameters estimations, and to optimize parameters. Ensemble hindcasts showed that the MCWLA-Wheat could capture the interannual variability of detrended historical yield series fairly well, especially over a large area. Finally, based on the MCWLA-Wheat, a super-ensemble-based probabilistic projection system was developed and applied to project the probabilistic responses of wheat productivity and water use in the North China Plain (NCP) to future climate change. The system used 10 climate scenarios consisting of the combinations of five global climate models and two greenhouse gases emission scenarios (A1FI and B1), the corresponding atmospheric CO2 concentration range, and multiple sets of crop model parameters representing the biophysical uncertainties from crop models. The results showed that winter wheat yields in the NCP could increase with high probability in future due to climate change. During 2020s, 2050s, and 2080s, with (without) CO2 fertilization effects, relative to 1961–1990 level, simulated wheat yields would increase averagely by up to 37.7% (18.6%), 67.8% (23.1%), and 87.2% (34.4%), respectively, across 80% of the study area; simulated changes in evaportranspiration during wheat growing period would range generally from −6% to 6% (−0.6% to 10%), from −10% to 8% (−1.0% to 17%), and from −17% to 4% (7–12%), respectively, across the study area. Further analyses suggested that the improvements in heat and water resources and rising atmospheric CO2 concentration ([CO2]) could contribute notably to wheat productivity increase in future. Climate change could enhance the development and photosynthesis rate; however the duration of reproductive period could be less affected than that of vegetative period, and wheat productivity could benefit from enhanced photosynthesis due to climate change and rising [CO2]. Furthermore, wheat could become mature earlier, which could prevent it from severe high temperature stress. Our study parameterized explicitly the effects of high temperature stress on productivity, accounted for a wide range of crop cultivars with contrasting phenological and thermal characteristics, and presented new findings on the probabilistic responses of wheat productivity and water use to climate change in the NCP.