Related Changes Research Articles

Spatial and Temporal Characteristics Analysis and Demand Forecasting based on ARIMA Model - An Example of Yellow Taxi in New York

With the development of technology and urbanization, cars have greatly facilitated people's travel, but they also bring problems such as road congestion, pollution and accidents, which restrict the healthy development of cities. How to predict traffic flow efficiently and accurately has become a hot topic. Taxi data is highly recommended in urban transportation research due to the characteristics of broad spatial coverage, long driving time and relatively complete data. In this paper, the data of yellow taxis in New York during March 2023 are used to present the demand changes by means of line chart thermal map, and divide the database of March into two parts, one is training set and the other one is test set, then simulation and analysis using ARIMA model. It reveals the changing relationship between taxi demand and time. By predicting the traffic flow, this study can alleviate the congestion of urban main roads and improve the quality of citizens’ life. At the same time, forecasting commuting demand can balance supply and demand, provide more efficient services for operating companies, taxi drivers and passengers, and provide decision-making basis for government planning.

Transformation From Atypical to Anaplastic Metastatic Meningioma: Evolutionary Turning Point Marked by Strong 18 F-FDG Avidity and Uptake Collapse From 68 GA-DOTATOC.

World Health Organization (WHO) grade III anaplastic meningioma is scarce. In this way, most studies compared WHO grade I and II. Otherwise, some authors are uncertain about using 18 F-FDG as a diagnostic tool to estimate the WHO grade, especially high. We report the case from a man with a grading tumor evolution from WHO grade II atypical to grade III anaplastic metastatic meningioma. This turning point was imaged using 68 Ga-DOTATOC and 18 F-FDG. Diagnostic was confirmed by histology. The case underlines the unparalleled power of molecular imaging characterized by high sensitivity staging and spectacular avidity changing relationship with grading tumor evolution.

Can you keep a secret? Family histories, secrets and ethics

Secrets are important for understanding interpersonal and family relationships. They give insights into the dynamics, processes, interactions and bonds that are developed, interrupted or revisited throughout life. We address family secrets as observatories of interpersonal relationships in two ways. One relates to how the disclosed secrets reveal social norms and social changes in family relationships. The second relates to telling an individual or family secret during a research interaction and what ethical issues and practices this disclosure implied. We address these issues through the secrets that emerged from 49 interviews carried out within a family histories research project with 15 Portuguese families. We identified a variety of family secrets related in particular to family and reproduction, money and addiction. The emergence of secrets in the interviewees’ narratives reveals the fundamental role of secrets in attributing meanings to biographies and family histories.

Restraining the Senses and Relations of Care

This article puts late Vedic ritual and the renouncer and householder traditions of early South Asia into dialogue in a new way, by thinking about restraining the senses through the etic lens of regimes of care. Guiding questions in this study are: (1) How do regimes of care help us understand the conceptual interface of violence, restraint, purity and community? (2) How do shifting relations of care help us understand conceptual change over time? Finally, (3) how does conceptual change help us speculate productively about changes in relations of care? The clear thematic bifurcation in the texts will recapitulate what Nathan McGovern has termed a ‘broad, trans-sectarian tension between renunciate and householder lifestyles’.

COVID-19 INFORMATION ELICITING STEREOTYPE THREAT CAN HARM OLDER ADULTS’ COGNITIVE FUNCTION

Abstract During the COVID-19 pandemic, older adults were identified as an at-risk group for developing severe physical symptoms. In addition to physical presentations, evidence indicated COVID-19 related changes in cognitive and neurological function; specifically, increased risk of stroke, reduced attention, concentration, and memory problems. Given that older adults remain particularly vulnerable to severe symptoms, exposure to information about COVID-19 and the associated cognitive symptoms may have adverse effects on their cognitive performance. This phenomenon, known as stereotype threat, describes situations in which negative stereotypes about a particular group can impair functioning. The current study aims to examine how exposure to adverse age-related information about the pandemic may impact cognitive performance compared to more neutral age-related information. 484 older adults were recruited February through July 2023 via Amazon Mechanical Turk and Cloud Research Connect. Participants were randomly assigned to a neutral or threat condition and read a paragraph related to aging or COVID-19, respectively. Afterwards, participants completed a memory task followed by a series of questionnaires to assess demographics, mood, depression, and COVID-19 health history. A one-way ANCOVA was conducted to evaluate the effect of COVID-19 threat on memory performance while controlling for history of COVID diagnosis. Findings indicate a significant difference in scores such that individuals in the threat condition had worse memory performance, compared to those in the neutral condition. This suggests that just reading information about COVID-19 may pose a threat to older adults’ cognitive abilities and further demonstrates the far-reaching effect the pandemic has had on individuals.

The moderating effects of mobile applications on the use of urban green space and mental health of older people: A mixed-method investigation in Hong Kong

Existing literature on the relationship between urban green space (UGS) use and mental health of older people was mainly conducted before the widespread adoption of digital technologies in daily life. In particular, the COVID-19 pandemic outbreak has fostered the use of mobile applications (apps) at a time city dwellers, including older people, were required to stay home. Drawing upon the insights from emerging literature on the changing relationship between UGS use and mental health of older people in the digital era in urban and gerontological studies, this paper offers a vivid mixed-method to investigate whether mobile app use has supplemented or substituted UGS visits and activities that further influence on the mental health of older people. This is achieved by conducting 360 questionnaire surveys in elderly community centers amid the pandemic and 23 semi-structured interviews in local neighbourhood parks after the pandemic by the authors. Results demonstrates mobile app use frequency may moderate the proximity-mental health relationship, but only among the older people with lower mental health levels. Among this sub-group, digital consumption app use frequency weakens the proximity-mental health relationship on marginal significance, which illustrates digital consumption apps may substitute the role of urban parks on improving older people’s mental health. Furthermore, digital communication and recreation mobile app use frequency strengthens the proximity-mental health relationship on marginal significance, which suggests these mobile apps may supplement the role of urban parks on improving older people’s mental health, particularly during the pandemic. The research pleas for more research on how digitalization of everyday activities is transforming the use of UGS such as neighbourhood parks and subsequent impact on the mental health of older people in the widespread adoption of digital technologies.

Task-oriented exercise effects on walking and corticospinal excitability in multiple sclerosis: protocol for a randomized controlled trial

BackgroundMultiple sclerosis (MS) is a degenerative disease of the central nervous system (CNS) that disrupts walking function and results in other debilitating symptoms. This study compares the effects of ‘task-oriented exercise’ against ‘generalized resistance and aerobic exercise’ and a ‘stretching control’ on walking and CNS function in people with MS (PwMS). We hypothesize that task-oriented exercise will enhance walking speed and related neural changes to a greater extent than other exercise approaches.MethodsThis study is a single-blinded, three-arm randomized controlled trial conducted in Saskatchewan, Canada. Eligible participants are those older than 18 years of age with a diagnosis of MS and an expanded Patient-Determined Disease Steps (PDDS) score between 3 (‘gait disability’) and 6 (‘bilateral support’). Exercise interventions are delivered for 12 weeks (3 × 60-min per week) in-person under the supervision of a qualified exercise professional. Interventions differ in exercise approach, such that task-oriented exercise involves weight-bearing, walking-specific activities, while generalized resistance and aerobic exercise uses seated machine-based resistance training of major upper and lower body muscle groups and recumbent cycling, and the stretching control exercise involves seated flexibility and relaxation activities. Participants are allocated to interventions using blocked randomization that stratifies by PDDS (mild: 3–4; moderate: 5–6). Assessments are conducted at baseline, post-intervention, and at a six-week retention time point. The primary and secondary outcome measures are the Timed 25-Foot Walk Test and corticospinal excitability for the tibialis anterior muscles determined using transcranial magnetic stimulation (TMS), respectively. Tertiary outcomes include assessments of balance, additional TMS measures, blood biomarkers of neural health and inflammation, and measures of cardiorespiratory and musculoskeletal fitness.DiscussionA paradigm shift in MS healthcare towards the use of “exercise as medicine” was recently proposed to improve outcomes and alleviate the economic burden of MS. Findings will support this shift by informing the development of specialized exercise programming that targets walking and changes in corticospinal excitability in PwMS.Trial registrationClinicalTrials.gov, NCT05496881, Registered August 11, 2022. https://classic.clinicaltrials.gov/ct2/show/NCT05496881. Protocol amendment number: 01; Issue date: August 1, 2023; Primary reason for amendment: Expand eligibility to include people with all forms of MS rather than progressive forms of MS only.

Trends in the decapod crustacean community at the southernmost estuary of the Atlantic coast of Europe

Climate change may enhance the establishment of introduced species, as well as the poleward shift in distribution of numerous species over decades. Long-term research and monitoring of an ecosystem at the southernmost point of the Atlantic coast of Europe should be an important priority in order to detect and understand trends in species composition and the related environmental changes. The Guadalquivir estuary (South West Spain) is more likely to suffer the exacerbated effects of climate change due to its location in the Mediterranean-climate zone. The long-term data set between 1997 and 2006 has allowed us to analyse the variability of the natural and anthropogenic stressors. The mean interannual dissimilarity of the estuarine fauna (Bray–Curtis dissimilarity index) has showed important differences throughout the years, and the species that most contributed to these differences were the exotic species capable of completing their life cycles. This long-term monitoring of the estuarine community has allowed us to anticipate future events and ecological risk assessment in European waters.

I and thou in dialogue: Becoming more relational in couple therapy.

Couple therapists have the unique and challenging opportunity of helping people find deeper connection in their intimate relationships. These clinicians apply therapeutic models and interventions designed to help couples. However, many of these models are derived from theoretical, scientific, and sociocultural traditions that conceptualize human phenomena as individualistic and reductionistic, and the language in these theories may not match clients' experiences, which include deeply relational phenomena such as love and loss. We review how Western scientific and sociocultural traditions have shaped conceptualization of problems and clinical intervention in couple therapy. In contrast, we provide an alternative, strongly relational framework for couple therapy that draws upon philosophical perspectives asserting that relational, rather than individual, experience is fundamental in human interaction. These ideas provide relational language which can influence how couple therapy is viewed and enacted. Specifically, we discuss how a strongly relational approach changes how therapists understand and intervene with conflict, abuse, love, and deception. This relational framework can help couples in their own goals to become more unified. Implications for the therapeutic relationship, interventions, and scholarship are provided.

Rural forested community shocks as perceived by in-migrants versus long-term residents

Rural communities face challenges and opportunities through changing relationships to natural resources that they depend on socially and culturally. Structural shifts in community-natural resource interactions may be expressed as “shocks”, or disruptions that create community change across multiple scales. These shocks may be isolated or connected events, and frequently have associated ripple effects. Our objectives were to (1) identify community shocks based on local resident perspectives, (2) evaluate regional variability of resident-perceived shock events, and (3) assess variation in perceptions of shocks between newer in-migrant and long-term residents. We used a mail survey to collect data from residents in rural New York, Ohio, Maine, and West Virginia (USA). Rather than starting with designated perspectives from past research, we used an inductive approach to identify shock events and their impacts. Categories of major shock events included, but were not limited to, employment loss, land transfers and designations, infrastructure development, loss of institutions, and natural disasters. Each community's history, shocks, and outcomes were uniquely place-dependent. Shocks identified and perception of them varied by residential tenure. Although identified similarly in a general sense by all respondents, details about individual shocks were more elaborately described by long-term residents, and in-migrants conveyed awareness of historical shocks. Conceptualizations of discrete, identifiable, and individual “shock” events are too simple and narrow for elucidating ongoing community perturbations that accumulate, counteract, and influence each other.

Demographic mechanisms and anthropogenic drivers of contrasting population dynamics of hummingbirds

Conserving species requires knowledge of demographic rates (survival, recruitment) that govern population dynamics to allow allocation of limited resources to the most vulnerable stages of target species' life-cycles. Additionally, quantifying drivers of demographic change facilitates enactment of specific remediation strategies. However, knowledge gaps persist in how similar environmental changes lead to contrasting population dynamics through demographic rates. For sympatric hummingbird species, the population of urban-associated partial-migrant Anna's hummingbird (Calypte anna) has increased, yet the populations of Neotropical migrants including rufous, calliope, and black-chinned hummingbirds have decreased. Here, we developed an integrated population model to jointly analyze 25 years of mark-recapture data and population survey data for these four species. We examined the contributions of demographic rates on population growth and evaluated the effects of anthropogenic stressors including human population density and crop cover on demographic change in relation to species' life histories. While recruitment appeared to drive the population increase of urban-associated Anna's hummingbirds, decreases in juvenile survival contributed most strongly to population declines of Neotropical migrants and highlight a potentially vulnerable phase in their life-history. Moreover, rufous hummingbird adult and juvenile survival rates were negatively impacted by human population density. Mitigating threats associated with intensively modified anthropogenic environments is a promising avenue for slowing further hummingbird population loss. Overall, our model grants critical insight into how anthropogenic modification of habitat affects the population dynamics of species of conservation concern.

Cerebral perfusion differences are linked to executive function performance in very preterm-born children and adolescents

Children and adolescents born very preterm are at risk of cognitive impairment, particularly affecting executive functions. To date, the neural correlates of these cognitive differences are not yet fully understood, although converging evidence points to a pattern of structural and functional brain alterations, including reduced brain volumes, altered connectivity, and altered brain activation patterns. In very preterm neonates, alterations in brain perfusion have also been reported, but the extent to which these perfusion alterations persist into later childhood is not yet known. This study evaluated global and regional brain perfusion, measured with arterial spin labelling (ASL) MRI, in 26 very preterm children and adolescents and 34 term-born peers. Perfusion was compared between groups and relative to executive function (EF) scores, derived from an extensive EF battery assessing working memory, cognitive flexibility, and planning. Very preterm children and adolescents showed regions of altered perfusion, some of which were also related to EF scores. Most of these regions were located in the right hemisphere and included regions like the thalamus and hippocampus, which are known to play a role in executive functioning and can be affected by prematurity. In addition, perfusion decreased with age during adolescence and showed a significant interaction between birth status and sex, such that very preterm girls showed lower perfusion than term-born girls, but this trend was not seen in boys. Taken together, our results indicate a regionally altered perfusion in very preterm children and adolescents, with age and sex related changes during adolescence.

A Political Economy of Historical Change and Continuity in Turkish Foreign Policy

This study aims to analyse historical continuity and change in Turkish foreign policy (TFP) within the framework of Critical Theory as elucidated by Robert Cox. It suggests asking how TFP has been affected by the historical changes in relations of production and world orders. Within this framework, it aims to explain the changes in TFP within the relation between the production, the world order and the form of state. It analyses TFP in three historical periods such as the Interwar Years, Cold War and post-Cold War. It exposes that Turkish state (re)formation and foreign policy making has succumbed to the global capitalist relations of production and corresponding world orders. These two have been the major framework(s) of change and continuity in Türkiye’s 100 years-old foreign policy. Its main argument is that the continuity and change in TFP has shown an interplay of relations between production and world order. It concludes that TFP has been in line with the global relations of production so there has been a clear and substantial continuity; and that the arguable changes have been the repercussions of global relations of production and world orders.

Virtual Eulogies, Rituals, and Burials: Experiences of and Adaptations to Death and Mourning During the COVID-19 Pandemic among Transnational Families

This paper is based on in-depth qualitative data from key informants (i.e., village heads, and employees of burial societies) and dyads from five families interviewed between March 2020 and December 2022 in Tsholotsho and Johannesburg to explore the experiences of and adaptations to death within transnational families during the COVID-19 pandemic. This follows the extraordinary autocratic governance and weaponisation of COVID-19 and the resulting travel restrictions between Zimbabwe and South Africa. The paper finds that amid mobility constraints, families experienced sociocultural changes in relation to death, causing them to experience death and mourning in unorthodox ways. For example, they participated in online memorial, funeral, and burial services and eulogies, thus embracing transnationalism by virtually participating in funerary processes at home in Zimbabwe while based in South Africa. It concludes that these virtual rituals, while giving members an appreciated sense of togetherness, did not sufficiently satisfy families’ social and psychological needs nor regard their heterogeneous cultural values, beliefs, and norms concerning death. The paper acknowledges the evolving nature and complexity of the post-colonial family and its death practices. However, it stresses how the COVID-19 epidemic transformed relationships and the sense of belonging of transnational families usually displayed in death situations.

Social restrictions, leisure and well-being

A wide-ranging public debate surrounds how pandemic lockdown measures differentially impacted individuals and which precise mechanisms – whether financial-, health-, or policy-driven – predominate in determining these effects. Using a nationally representative 24-h diary survey covering the first two years of the pandemic, we explore potential mechanisms underlying changes in well-being. We exploit the variation in the stringency of the social restrictions implemented by the UK government during this period and use an event-study methodology to net out the impact of social restrictions from other pandemic effects. We find that well-being dropped by 47 % (for men) and 71 % (for women) of a standard deviation during the strictest lockdown and that it took longer to revert to pre-pandemic levels than previously estimated. This finding holds after we account for financial conditions and changes in local infection and death rates, suggesting that the time use–related changes driven by social restrictions dominate financial and health shocks in driving the overall well-being effects during the pandemic. Our detailed data on time allocation and individual preferences over the activities undertaken throughout the day suggest that the drop in well-being was primarily associated to a drastic reduction in time spent in leisure with non–household members or outside the home, a category with greater weight in the well-being of women.

Модель региональной транспортной сети для построения рациональных мультимодальных маршрутов пассажирских перевозок

Purpose: Adaptation of methods of constructing models of transport networks for the development of rational multimodal routes of regional passenger transportation, as well as the creation of a software product for the practical implementation of the proposed algorithms. Methods: Mathematical modeling; graph theory for solving regional transportation problems with construction of two-level oriented weighted multigraphs; Analysis of existing algorithms for optimizing the search for graph solutions; Dijkstra’s algorithm. Results: The model of the regional passenger transport network has been implemented in the form of a calculation program developed by the authors. In this program, the schedule of the movement of all transport points under consideration is the initial data, and the result is the construction of rational multimodal routes. The calculation program is compiled from several modules that implement the following functionality in general: reading input data from files; the formation of an array of connections for the problems under consideration; search for a rational solution and output of the received data while saving it to the file. The optimization criterion when choosing a route can be the minimum travel time, distance, or cost of the trip, depending on the task and input data provided. The resulting array of data with the results has been further analyzed using the MS Excel table editor. This approach is selected due to sufficient flexibility when performing a variety of data analysis and the convenience of graphic presentation of the results. Practical significance: The development of rational multimodal routes, relevant primarily for cases of abrupt changes in transport relations, in which the extrapolation methods of existing passenger flow do not provide reliable forecast data. Justification of the adjustment of the schedules of regional passenger routes based on the results of the analysis of the demand and the load of their specific segments.

ПОЛИТИКА БЕЗОПАСНОСТИ САУДОВСКОЙ АРАВИИ КАК РЕГИОНАЛЬНОЙ ДЕРЖАВЫ В ОДНОПОЛЯРНОЙ СИСТЕМЕ (2010-2020)

When the security policies of Saudi Arabia between 2000-2010 and 2010-2020 are examined, it can be seen that although there is no change in the internal threats to the Saudi Arabian Regime, there has been a change and transformation in its external threats. Therefore, although the internal threats are the same, in the alliance relations it has formed to balance the internal threats with the interrelated external threats, the interrelated external threats and the main threat have changed. In this case, it shows us that state behavior and alliance relations are constantly re-established as instant security measures. Threats, which are also seen as the dynamic structure of the international system, and the change in alliance relations necessitate a multifaceted approach for regional powers. This is also due to the features of Saudi Arabia such as the monarchical state structure, the competing allegiencies of the people, and the fact that it is a rentier state. For societies where the security of the regime is more important and prioritized than the security of the state due to internal threats, it should have multi-layered factors to ensure their security, because of their local characteristics. For Saudi Arabia, these factors consist of internal threats, an external threat interrelated with an internal threat, and regional and global threats. This situation gives rise to the omni-balancing strategy, which means that Saudi Arabia forms alliances with foreign powers interrelated to its internal threats and balances internal and external threats with each other. In cases where omni-balancing is not possible, various reforms, social assistance and cooperation initiatives come into play.

EMPOWERMENT OF WOMEN VULNERABLE TO REPRODUCTIVE DISEASES IN MAJLIS TA'LIM AL-FARIZI COMMUNITY, SUKAMENTRI VILLAGE, GARUT CITY SUB-DISTRICT, GARUT REGENCY

Technological changes and modernization in various sectors today are so rapid, that they affect human behavior in various ways. Technology on the one hand has a positive impact on people's lives, but on the other hand, technology also hurts society. Along with the development of technology, the need for plastic continues to increase. Plastic is also an artificial inorganic material composed of chemicals that are quite harmful to the environment and health. The purpose of this service is to increase the productivity skills of mothers in Sukamentri Village by providing safer bags made from nature to replace plastic items and utilize plastic waste with varied crafts. The method used is (Participatory Action Research) (PAR) is a research method carried out in a participatory manner among citizens in a lower-level community whose spirit is to encourage transformative actions to liberate society from the shackles of ideology and power relations (changes in better living conditions). The results of the Pangabdian activity were carried out well and received a positive response, this was seen from the enthusiasm of the participants by arriving on time, and the understanding of mothers about the dangers of using plastic waste increased. The increase in understanding is evidenced by the results of the pre-test before the delivery of the material and the post-test after the delivery of the material which shows the Mean with a result of 0.252 is positive, which means an increase after being given treatment. This activity is also aimed at improving the skills of mothers in processing waste waste, especially plastic waste with ecobrick techniques and minimizing the use of plastic for daily purposes. The resulting products are expected to improve the community's economy and provide positive activities for the group of mothers in Majlis Ta'lim Al-Farizi.

Schinus molle for refugia for diversity of epiphytic cryptogams as indicators of air pollution in Quito, Ecuador

Air pollution in urban areas due to automotive and industrial emissions is a global problem, including the city of Quito- Ecuador. In this context, previous studies have pointed out the effective use of bioindicators of air quality using epiphytic cryptogams (bryophytes and lichens), which are pollutant-sensitive organisms because they absorb water and nutrients from the environment. In this study, we determined for the first time the changes in the richness and composition epiphytic cryptogams in the host tree Schinus molle comparing areas of high, medium, and low vehicular traffic. For this purpose, we registered the frequency and coverage of lichens and bryophytes with a grid of 10 x 50 cm, divided into twenty squares of 5 x 5 cm on Schinus molle trees. We recorded 30 species (23 lichens and 7 bryophytes). Richness, cover and diversity did not indicate changes in relation to vehicular traffic, however, the composition of the communities indicated slight changes in relation to vehicular traffic. Species composition indicated changes in relation to vehicular traffic, where species of the genera Leptogium and Teloschistes were dominant in low traffic areas, conversely species of genera Candelaria, Physcia and Frullania was observed in areas with higher traffic that are tolerant to pollution. Schinus molle is a very important species as a refuge for diversity of epiphytic cryptogams in urban areas.

Activity budget and gut microbiota stability and flexibility across reproductive states in wild capuchin monkeys in a seasonal tropical dry forest

BackgroundEnergy demands associated with pregnancy and lactation are significant forces in mammalian evolution. To mitigate increased energy costs associated with reproduction, female mammals have evolved behavioural and physiological responses. Some species alter activity to conserve energy during pregnancy and lactation, while others experience changes in metabolism and fat deposition. Restructuring of gut microbiota with shifting reproductive states may also help females increase the energy gained from foods, especially during pregnancy. The goal of this study was to examine the relationships among behaviour, gut microbiota composition, and reproductive state in a wild, non-human primate to better understand reproductive ecology. We combined life history data with > 13,000 behavioural scans and 298 fecal samples collected longitudinally across multiple years from 33 white-faced capuchin monkey (Cebus imitator) females. We sequenced the V4 region of the 16S rRNA gene and used the DADA2 pipeline to analyze microbial diversity. We used PICRUSt2 to assess putative functions.ResultsReproductive state explained some variation in activity, but overall resting behaviours were relatively stable across pregnancy and lactation. Foraging was less frequent among females in the early stage of nursing compared to the cycling stage, though otherwise remained at comparable levels. Maximum temperature was a strong, significantly positive predictor of resting, while social dominance had a small but significantly negative effect on resting. Ecological variables such as available fruit biomass and rainfall had a small but significantly positive effects on measures of foraging time. Gut microbial community structure, including richness, alpha diversity, and beta diversity remained stable across the reproductive cycle. In pairwise comparisons, pregnant females exhibited increased relative abundances of multiple microbial ASVs, suggesting small changes in relation to reproductive state. Reproductive state was not linked to differential abundance of putative metabolic pathways.ConclusionsPrevious data suggest that activity budget and the gut microbiome shifts considerably during reproduction. The present study finds that both activity and gut microbial communities are less associated with reproduction compared to other predictors, including ecological contexts. This suggests that behavioural flexibility and gut microbial community plasticity is contrained by ecological factors in this population. These data contribute to a broader understanding of plasticity and stability in response to physiological shifts associated with mammalian reproduction.