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The purpose of the quantitative ex post facto design of this study was to determine if, and to what extent, self-efficacy increases after the implementation of a pre-entry program for community college student athletes in Southern California. The self-efficacy theory provided the theoretical foundation to address the research questions in this study. The sample was composed of 21 community college student athletes in Southern California who completed a pre-entry program during the 2018/2019 and 2019/2020 academic years. The result of the paired samples t-test revealed the physiological states scores were significantly lower for the posttest (M-post = 26.24, SD = 1.660) than for the pretest (M-pre = 28.29, SD = 7.805), t(20) = 1.864, p = 0.038. There were nonstatistically significant main effects for overall self-efficacy, mastery experiences, vicarious learning, and social persuasion scores. These findings have implications for future research based on the study's strengths and weaknesses, and the results lay the groundwork for future research for improving the transition into community college for student athletes.

Assessments are common in undergraduate classrooms, with formats including multiple-choice and open-ended (in which the students must generate their own answers) questions. While much is known about the strategies that students use when taking multiple-choice questions, there has yet to be a study evaluating the strategies that students employ during open-ended test questions. The current study used phenomenography and an open-ended online survey to solicit strategies from 416 students in an upper division reproductive physiology class across two quarters. Fifteen different categories of student strategy were categorized across four broad themes: formulating an answer, writing a response, time management, and question details. A detailed account of each of the 15 categories is presented along with an assessment of how each category is both unique and similar to other categories. The results of the current study could have important implications for teaching, as several of the strategies reported by students are likely not in line with those desired by course instructors.

An important question regards how we use environmental boundaries to anchor spatial representations during navigation. Behavioral and neurophysiological models appear to provide conflicting predictions, and this question has been difficult to answer because of technical challenges with testing navigation in novel, large-scale, realistic spatial environments. We conducted an experiment in which participants freely ambulated on an omnidirectional treadmill while viewing novel, town-sized environments in virtual reality on a head-mounted display. Participants performed interspersed judgments of relative direction (JRD) to assay their spatial knowledge and to determine when during learning they employed environmental boundaries to anchor their spatial representations. We designed JRD questions that assayed directions aligned and misaligned with the axes of the surrounding rectangular boundaries and employed structural equation modeling to better understand the learning-dependent dynamics for aligned versus misaligned pointing. Pointing accuracy showed no initial directional bias to boundaries, although such "alignment effects" did emerge after the fourth block of learning. Preexposure to a map in Experiment 2 led to similar overall findings. A control experiment in which participants studied a map but did not navigate the environment, however, demonstrated alignment effects after a brief, initial learning experience. Our results help to bridge the gap between neurophysiological models of location-specific firing in rodents and human behavioral models of spatial navigation by emphasizing the experience-dependent accumulation of route-specific knowledge. In particular, our results suggest that the use of spatial boundaries as an organizing schema during navigation of large-scale space occurs in an experience-dependent fashion.

While humour and laughter create conditions that are conducive for learning, different forms of children's humour have been given little attention in research on digital media, literacy learning, and multimodal design. Applying a Bakhtinian lens, we analyse carnivalesque videos created by elementary students as part of the formal curriculum. We argue that they functioned as playful, spoofing counter narratives within the serious context of schooling. Three key findings emerge from analysis that show different forms of carnivalesque humour in their texts: (i) Clowning in children's carnivalesque performances was used to break perceived tensions; (ii) Grotesque humour arose spontaneously, subverting the seriousness of films by drawing attention to lower, bodily functions; and (iii) Ambivalent laughter was instantiated in the video texts as a carnivalesque view of the world. We argue that the deliberate curation, editing, and selecting of these funny moments for an intended audience enabled spaces for digital play in film making within the remit of the formal curriculum.

Different versions of multiple-choice exams were administered to an undergraduate class in human physiology as part of normal testing in the classroom. The goal was to evaluate whether the number of options (possible answers) per question influenced the effectiveness of this assessment. Three exams (each with three versions) were given to each of two sections during an academic quarter. All versions were equally long, with 30 questions: 10 questions with 3 options, 10 questions with 4, and 10 questions with 5 (always one correct answer plus distractors). Each question appeared in all three versions of an exam, with a different number of options in each version (three, four, or five). Discrimination (point biserial and upper-lower discrimination indexes) and difficulty were evaluated for each question. There was a small increase in difficulty (a lower average score on a question) when more options were provided. The upper-lower discrimination index indicated a small improvement in assessment of student learning with more options, although the point biserial did not. The total length of a question (number of words) was associated with a small increase in discrimination and difficulty, independent of the number of options. Quantitative questions were more likely to show an increase in discrimination with more options than nonquantitative questions, but this effect was very small. Therefore, for these testing conditions, there appears to be little advantage in providing more than three options per multiple-choice question, and there are disadvantages, such as needing more time for an exam. [Partial funding for A. Macias-Muñoz was provided by National Science Foundation Bio/computational Evolution in Action Consortium, Division of Biological Infrastructure.]

Despite adolescence being a period marked by significant social changes, research on social status focuses largely on adults. This study examined whether school and societal subjective social status (SSS) are differentially associated with adolescent health above and beyond objective socioeconomic status (SES), and explored pathways linking SSS to health. Latino (n = 169) and Asian American (n = 77) adolescents (M age = 17.23, SD = 0.74; 59% female) completed self-reports of SSS, sleep, stress, and somatic symptoms. Parents reported income and education. Blood pressure (BP) measurements were obtained. Results indicate that independent of objective SES, lower school SSS was associated with higher diastolic BP whereas lower societal SSS was associated with more somatic symptoms. Sleep disruptions and perceived stress mediated the association between societal SSS and somatic symptoms. Results suggest that SSS may be more important to adolescent health than objective SES. Furthermore, school and societal SSS may differentially affect indicators of health through different pathways.

Certain psychopathologies are often linked to dysregulation of specific emotions (e.g., anxiety is associated with dysregulation of fear), but few studies have examined how regulatory repertoires for specific emotions (e.g., the strategies a person uses to regulate fear) relate to psychopathology, and fewer still have examined this in childhood. A total of 106 7- to 11-year-olds (M = 9.37 years; SD = 1.30; 44% girls) participated in a multimethod investigation of emotion regulation and psychopathology. Parents reported on family characteristics and children's symptoms. Resting parasympathetic function (respiratory sinus arrhythmia; RSA) was measured to assess physiological regulation. Children were interviewed about past experiences that made them feel anger, fear, and sadness, and reported what they had done to make themselves feel better in each emotion context. The strategies children described were summed to create an emotion regulation strategy repertoire measure for each emotion. Children's resting RSA interacted with age to predict externalizing symptoms, such that low resting RSA was associated with more externalizing symptoms for younger children only. In contrast, the link between RSA and anxiety was qualified by both strategy repertoire for fear and age, such that higher resting RSA was most strongly associated with fewer anxiety symptoms for older children with larger strategy repertoires for fear. Contrary to our expectations, neither resting RSA nor strategy repertoire for sadness related to children's depressive symptoms. Findings underscore the importance of considering children's discrete emotion regulation strategy repertoires to more fully characterize the dysregulated affective processes associated with psychopathology in childhood.

For many the thought of students taking an online course conjures up images of students sitting at a computer desk. Students taking online physical education (OLPE) at home may lack opportunities for competitive or cooperative physical activity that are available to students in a traditional setting. Active video games (exergames) can be played over the internet between students. Exergames allow for a new and possibly effective genre of physical activity that offers OLPE students the opportunity to interact in relevant, engaging, and entertaining physical activity with other students. Secondary student (N = 124) heart rates were recorded before exergaming, after playing a non-player character, and after playing another student remotely over the internet. The results show that exergaming between students over the internet can raise student heart rates to moderate levels of physical intensity commensurate with guidelines for Physical Intensity for secondary students. Exergames show promise for physical activity in an OLPE course when played against a non-player character and a remote partner.

Older adults often report less affective reactivity to interpersonal tensions than younger individuals, but few studies have directly investigated mechanisms explaining this effect. The current study examined whether older adults' differential endorsement of goals, appraisals, and emotion regulation strategies (i.e., conflict avoidance/de-escalation, self-distraction) during a controlled negative social interaction may explain age differences in affective and cardiovascular responses to the conflict discussion. Participants (N = 159; 80 younger adults, 79 older adults) discussed hypothetical dilemmas with disagreeable confederates. Throughout the laboratory session, participants' subjective emotional experience, blood pressure, and pulse rate were assessed. Older adults generally exhibited less reactivity (negative affect reactivity, diastolic blood pressure reactivity, and pulse rate reactivity) to the task and more pronounced positive and negative affect recovery following the task than did younger adults. Older adults appraised the task as more enjoyable and the confederate as more likeable and more strongly endorsed goals to perform well on the task, which mediated age differences in negative affect reactivity, pulse rate reactivity, and positive affect recovery (i.e., increases in posttask positive affect), respectively. In addition, younger adults showed increased negative affect reactivity with greater use of self-distraction, whereas older adults did not. Together, findings suggest that older adults respond less negatively to unpleasant social interactions than younger adults, and these responses are explained in part by older adults' pursuit of different motivational goals, less threatening appraisals of the social interaction, and more effective use of self-distraction, compared with younger adults.

The present study used a collaborative framework to integrate 2 long-term prospective studies: the Terman Life Cycle Study and the Hawaii Personality and Health Longitudinal Study. Within a 5-factor personality-trait framework, teacher assessments of child personality were rationally and empirically aligned to establish similar factor structures across samples. Comparable items related to adult self-rated health, education, and alcohol use were harmonized, and data were pooled on harmonized items. A structural model was estimated as a multigroup analysis. Harmonized child personality factors were then used to examine markers of physiological dysfunction in the Hawaii sample and mortality risk in the Terman sample. Harmonized conscientiousness predicted less physiological dysfunction in the Hawaii sample and lower mortality risk in the Terman sample. These results illustrate how collaborative, integrative work with multiple samples offers the exciting possibility that samples from different cohorts and ages can be linked together to directly test life span theories of personality and health.

In this project, the traditional lecture hall presentation of acid-base physiology in the first-year medical school curriculum was replaced by interactive, computer-assisted instruction designed primarily for the iPad and other mobile computer platforms. Three learning modules were developed, each with ~20 screens of information, on the subjects of the CO[subscript 2]-bicarbonate buffer system, other body buffer systems, and acid-base disorders. Five clinical case modules were also developed. For the learning modules, the interactive, active learning activities were primarily step-by-step learner control of explanations of complex physiological concepts, usually presented graphically. For the clinical cases, the active learning activities were primarily question-and-answer exercises that related clinical findings to the relevant basic science concepts. The student response was remarkably positive, with the interactive, active learning aspect of the instruction cited as the most important feature. Also, students cited the self-paced instruction, extensive use of interactive graphics, and side-by-side presentation of text and graphics as positive features. Most students reported that it took less time to study the subject matter with this online instruction compared with subject matter presented in the lecture hall. However, the approach to learning was highly examination driven, with most students delaying the study of the subject matter until a few days before the scheduled examination. Wider implementation of active learning computer-assisted instruction will require that instructors present subject matter interactively, that students fully embrace the responsibilities of independent learning, and that institutional administrations measure instructional effort by criteria other than scheduled hours of instruction.

Previous investigations found that a subset of children with autism spectrum disorder (ASD) in California possessed plasma autoantibodies that reacted intensely with brain interneurons or other neural profiles. Moreover, for several cohorts of American women, maternal autoantibody reactivity to specific fetal brain proteins was highly specific to mothers of children with ASD. We sought to determine whether children and their mothers from a regionally specific cohort from the Basque Country of Spain demonstrated similar reactivity. Some children's plasma reacted to interneurons, beaded axons or other neural profiles with no difference in the occurrence of these antibodies in children with or without ASD. Findings on the maternal antibodies confirmed previous research; plasma reactivity to fetal brain a combination of proteins at 37 and 73 kDa or 39 and 73 kDa was found exclusively in mothers of children with ASD.

Compare and contrast strategies remain common pedagogical practices within physiological education. With the support of an American Physiological Society Teaching Career Enhancement Award, we have developed a junior- or senior-level undergraduate curriculum for exercise physiology that compares and contrasts the physiological adaptations of chronic terrestrial exercise (TEx) and microgravity ([mu]G). We used a series of peer-reviewed publications to demonstrate that many of the physiological adaptations to TEx and [mu]G are opposite. For example, TEx typically improves cardiovascular function and orthostatic tolerance, whereas [mu]G can lead to declines in both. TEx leads to muscle hypertrophy, and [mu]G elicits muscle atrophy. TEx increases bone mineral density and red blood cell mass, whereas [mu]G decreases bone mineral density and red blood cell mass. Importantly, exercise during spaceflight remains a crucial countermeasure to limit some of these adverse physiological adaptations to [mu]G. This curriculum develops critical thinking skills by dissecting peer-reviewed articles and discussing the strengths and weaknesses associated with simulated and actual [mu]G studies. Moreover, the curriculum includes studies on both animals and humans, providing a strong translational component to the curriculum. In summary, we have developed a novel space physiology curriculum delivered during the final weeks of an exercise physiology course in which students gain critical new knowledge that reinforces key concepts presented throughout the semester.

Marital quality is an important factor for understanding the relationship between marriage and health. Low-quality relationships may not have the same health benefits as high-quality relationships. To understand the association between marital quality and health, we examined associations between two indicators of marital quality (marital support and marital strain) and two biomarkers of inflammation (interleukin-6 and C-reactive protein) among men and women in long-term marriages using data from the Survey of Midlife in the United States ("N" = 542). Lower levels of spousal support were associated with higher levels of inflammation among women but not men. Higher levels of spousal strain were weakly and inconsistently associated with higher levels of inflammation among women and men; the effects were diminished with the addition of psychosocial and behavioral covariates. These findings suggest marital quality is an important predictor of inflammation, especially among women. (Contains 3 tables, 2 figures, and 1 note.)

Associations among 53 primiparous women's Adult Attachment Interview classifications (secure-autonomous vs. insecure-dismissing) and physiological and self-reported responses to infant crying were explored. Heart rate, skin conductance levels, and respiratory sinus arrhythmia (RSA) were recorded continuously. In response to the cry, secure-autonomous women demonstrated RSA declines, consistent with approach-oriented responses. Insecure-dismissing women displayed RSA and electrodermal increases, consistent with behavioral inhibition. Furthermore, insecure-dismissing women rated the cries as more aversive than secure-autonomous women. Nine months postpartum, secure-autonomous women, who prenatally manifested an approach-oriented response to the unfamiliar cry stimulus, were observed as more sensitive when responding to their own distressed infant, whereas women classified prenatally as insecure-dismissing were observed as less sensitive with their own infants. (Contains 3 tables and 2 figures.)

A recently filed lawsuit in Compton, California ("Peter P. et al. v. Compton Unified School District," 2015) has been making national news. The lawsuit highlights the prevalence of trauma exposure, particularly among underserved youth, as well as the need for school-wide, trauma-informed practices to enhance resiliency among students and staff. The plaintiffs in the case cite empirical literature (i.e., the Adverse Childhood Experiences [ACE] study; Felitti et al., 1998) regarding the neurobiological and psychological effects of trauma exposure on children, specifically complex trauma (i.e., multiple or chronic trauma experiences, typically involving the primary caregiving system/individuals; www.nctsn.org). Research on the effect of trauma on learning was prominently reviewed and cited in the lawsuit. In the current article, the authors will give background information on this potentially groundbreaking lawsuit and discuss how the complaint provides a call for best practices for working with traumatized students in school systems, as well as possible changes and challenges that could follow.

In this article, the authors consider the possibility that groups could be different, because of the different conditions of a factor. This is as far as the analysis can extend: the consideration is restricted to groups characterized by the different category of the factor being considered. In many biological experiments, the factor considered may not be just a simple category, but it may be expressed in terms of order, or even as a continuous variable. If this can be done, then other helpful and powerful methods of statistical analysis can be used. The authors discuss linear regression analysis which considers variation in the "dependent" variable. (Contains 4 figures.)

This article describes a new hands-on, or "kinesthetic," activity for use in a physiology lecture hall to help students comprehend an important concept in cardiopulmonary physiology known as oxygen carrying capacity. One impetus for designing this activity was to address the needs of students who have a preference for kinesthetic learning and to help increase their understanding and engagement during lecture. This activity uses simple inexpensive materials, provides an effective model for demonstrating related pathophysiology, and helps promote active learning. The activity protocol and its implementation are described here in detail. We also report data obtained from student surveys and assessment tools to determine the effectiveness of the activity on student conceptual learning and perceptions. A brief multiple-choice pretest showed that although students had already been introduced to the relevant concepts in lecture, they had not yet mastered these concepts before performing the activity. Two postactivity assessments showed that student performance was significantly improved on the posttest compared with the pretest and that information was largely retained at the end of the course. Survey data showed that one-half of the students stated kinesthetic learning as among their learning preferences, yet nearly all students enjoyed and were engaged in this hands-on kinesthetic activity regardless of their preferences. Most students would recommend it to their peers and expressed a desire for more kinesthetic learning opportunities in the lecture curriculum. (Contains 2 footnotes, 3 tables, and 4 figures.)

Student learning may be classified according to the sensory modalities by which one prefers to take in information. One such classification scheme uses the VARK instrument, which categorizes learning preferences as visual (V), auditory (A), reading-writing (R), or kinesthetic (K). Many students have a single, strong preferences ("unimodal"), whereas others have multiple ("multimodal") learning preferences. Although limited in scope and reliability, knowledge of student learning preferences is important for reasons of pedagogy. Teaching and student learning styles may also affect student academic success in science coursework and fulfillment of student career goals. In our study, we determined the learning preferences of upper-division students in a human physiology course during a 2-yr period at a public undergraduate institution in California. We also sought to determine the association between individual learning styles and stated career intentions. We found that the majority of students interested in the health professions have multimodal learning preferences. Furthermore, a greater percentage of premedical students had multimodal preferences compared with predental and prescientist students. When data were compared by gender, we found that more female than male students had multimodal learning preferences. We also observed some gender differences when separating student groups by career choice. For example, more premedical men had multimodal preferences compared with nonpremedical men. In contrast to men, women showed little differences in their learning style profiles whether premedical or not and also self-predicted their learning preferences more accurately. Thus, career choice may be an important consideration in determining whether or not there are gender differences among students. (Contains 4 tables and 3 figures.)

This study aimed to determine the probability that a child with cerebral palsy (CP) will lose or gain ambulatory ability through adolescence and young adulthood. We analyzed retrospectively data from 1987 to 2002 on Californians with CP initially aged 10 years (SD 0.9y; n=7550 [4304 males, 3246 females]) and 25 years (SD 0.8y; n=5721 [3261 males, 2460 females]) who had varying levels of ambulatory ability (initial Gross Motor Function Classification System Levels I-IV). We used the Aalen-Johansen estimator to estimate probabilities of transition to other levels of ambulatory ability in the future. Those who walked and climbed stairs without difficulty at age 10 had only a 23% chance of decline (to requiring a handrail to manage stairs, or worse) 15 years later. Those who ambulated with some difficulty but did not use a wheelchair had a significant chance (33%) of improvement (to being able to walk unsteadily alone at least 3m or better) and only a small chance (11%) of becoming non-ambulatory. Those who used a wheelchair were more likely to lose ambulatory ability (34%) or die (6%). Those who walked and climbed stairs well at age 25 were likely to maintain that ability 15 years later (76%), while those needing support to climb stairs were more likely to lose ability. Improvement in ambulation after age 25 was unlikely. Children and young adults with CP are likely to maintain their ambulatory ability during their next 15 years. Some who ambulate with difficulty at age 10 may improve through adolescence, but those who use a wheelchair are more likely to decline. By age 25 improvement in ambulation is unlikely and decline more likely. Most, however, will not change over the next 15 years.

Self-reports of grade at first menstrual period for 1,967 fourth-grade through ninth-grade girls were used to categorize girls as early maturers. The categories of early maturer and other (on-time or late maturers) were then examined for stability over a 3-year period using McNemar tests and [kappa] coefficients. Although the results showed significant stability, 15% through 20% of the early maturing girls were eventually reclassified into the other category. This was true for Hispanic, Black, and White girls as well as for 1-, 2-, and 3-year time spans. Implications for measuring menarcheal timing and its effects are discussed. (Contains 3 tables and 1 note.)

Documenting the effects of crisis intervention work on school psychologists was the primary purpose of this study. To examine these effects a sample of 400 randomly selected school psychologists were surveyed. Half of the surveys were returned. Among respondents who had previously participated in a crisis intervention, just over 90% reported one or more of 37 specific negative reactions following crisis intervention work. Physical reactions in general and fatigue/exhaustion in particular were the most frequently reported reactions. All respondents reported use of self-care strategies and 94% viewed these strategies as important. Implications of these findings for the practice of school psychology are discussed. (Contains 1 table.)

Objectives: The purpose of this investigation was to complete a formal evaluation of Reading Across My Pyramid (RAMP), a literacy promoting nutrition and health education curriculum. Methods: To meet this need, a short survey, the "Child Survey," based on topics covered in RAMP lessons was developed and tested for clarity in a group of children attending a school eligible to receive the California Food Stamp Nutrition Education Program (FSNEP) (N = 20). Following testing, revisions were made accordingly and the Child Survey was used in Northern, Central, and Southern California Schools (N = 62) to evaluate RAMP. A "Parent Survey" was also used to determine correlations between the responses of children and their parents. Results: Data showed RAMP to be effective at increasing the importance of exercise in the minds of children (p = 0.001), knowledge that the heart pumps blood through the body (p < 0.001), and knowledge that computer use and television watching are not exercise (p = 0.024). Correlations were also observed between a child's knowledge of healthy foods and parent reported soda consumption (p = 0.01), and between child's knowledge that computer use and television watching are not exercise and parent reported hours of television watching by their child (p = 0.03). Application to Child Nutrition Professionals: The results of this investigation show that RAMP is effective at increasing the health behavior knowledge of lower elementary students. Currently, this curriculum is widely used throughout California by both the FSNEP and the Expanded Food and Nutrition Education Program (EFNEP). In a time when the rates of childhood overweight have reached epidemic proportions, these findings suggest that RAMP can be an effective tool for nutrition professionals to use to increase health behavior knowledge in an effort to reduce rates of childhood obesity.

Increasingly frequent and intense heatwaves threaten ecosystem health in a warming climate. However, plant responses to heatwaves are poorly understood. A key uncertainty concerns the intensification of transpiration when heatwaves suppress photosynthesis, known as transpiration–photosynthesis decoupling. Field observations of such decoupling are scarce, and the underlying physiological mechanisms remain elusive. Here, we use carbonyl sulphide (COS) as a leaf gas exchange tracer to examine potential mechanisms leading to transpiration–photosynthesis decoupling on a coast live oak in a southern California woodland in spring 2013. We found that heatwaves suppressed both photosynthesis and leaf COS uptake but increased transpiration or sustained it at non‐heatwave levels throughout the day. Despite statistically significant decoupling between transpiration and photosynthesis, stomatal sensitivity to environmental factors did not change during heatwaves. Instead, midday photosynthesis during heatwaves was restricted by internal diffusion, as indicated by the lower internal conductance to COS. Thus, increased evaporative demand and nonstomatal limitation to photosynthesis act jointly to decouple transpiration from photosynthesis without altering stomatal sensitivity. Decoupling offered limited potential cooling benefits, questioning its effectiveness for leaf thermoregulation in xeric ecosystems. We suggest that adding COS to leaf and ecosystem flux measurements helps elucidate diverse physiological mechanisms underlying transpiration–photosynthesis decoupling. Summary statement: During heatwaves, plants can lose more water to sustain the same level of photosynthesis, but it is unclear what makes them do so. Here, we leverage leaf carbonyl sulphide flux measurements to show that restricted gas diffusion within leaves led to this heatwave response in a southern California oak. [ABSTRACT FROM AUTHOR]

Premise: Previous studies have suggested a trade‐off between trichome density (Dt) and stomatal density (Ds) due to shared cell precursors. We clarified how, when, and why this developmental trade‐off may be overcome across species. Methods: We derived equations to determine the developmental basis for Dt and Ds in trichome and stomatal indices (it and is) and the sizes of epidermal pavement cells (e), trichome bases (t), and stomata (s) and quantified the importance of these determinants of Dt and Ds for 78 California species. We compiled 17 previous studies of Dt–Ds relationships to determine the commonness of Dt–Ds associations. We modeled the consequences of different Dt–Ds associations for plant carbon balance. Results: Our analyses showed that higher Dt was determined by higher it and lower e, and higher Ds by higher is and lower e. Across California species, positive Dt–Ds coordination arose due to it–is coordination and impacts of the variation in e. A Dt–Ds trade‐off was found in only 30% of studies. Heuristic modeling showed that species sets would have the highest carbon balance with a positive or negative relationship or decoupling of Dt and Ds, depending on environmental conditions. Conclusions: Shared precursor cells of trichomes and stomata do not limit higher numbers of both cell types or drive a general Dt–Ds trade‐off across species. This developmental flexibility across diverse species enables different Dt–Ds associations according to environmental pressures. Developmental trait analysis can clarify how contrasting trait associations would arise within and across species. [ABSTRACT FROM AUTHOR]

Many plant species can exhibit remarkable variation in leaf characteristics, depending on their abiotic and biotic environment. Environmental changes therefore have the potential to alter leaf traits, which in turn scale up to influence ecosystem processes including net primary productivity, susceptibility to fire, and palatability to herbivores. It is not well understood how consistent trait–environment relationships are among species, across sites and over time. This presents a fundamental challenge for functional ecology, because no study can measure all relevant species in all places at all times. Thus, understanding the limits of transferability is critical. We collected leaf trait measurements on 13 species of grass (family: Poaceae) across 11 sites and five years (n = 3091 individuals). Sites were arrayed along a spatial precipitation gradient in coastal northern California (annual precipitation of 590–1350 mm) with substantial interannual precipitation variability (from 60% below the 30‐year average to 100% above average). Temporal and spatial linear relationships between precipitation and specific leaf area (SLA) appear at first idiosyncratic, with each species sometimes displaying positive and sometimes negative responses. However, this variation arises from sampling different portions of an underlying hump‐shaped relationship, which was shared across most species. This hump‐shaped relationship was driven primarily by changes in leaf tissue density. These results suggest the potential for transferability among species, as well as between space and time, as long as the gradients are sufficiently long to capture the nonlinear response. Future work could explore the physiological basis of the nonlinear SLA response, including the possibility that distinct physiological mechanisms are operating at the two extremes of the gradient. [ABSTRACT FROM AUTHOR]

The measurement of stable isotope values of individual compounds, such as amino acids (AAs), has become a powerful tool in animal ecology and ecophysiology. As with any emerging technique, questions remain regarding the capabilities and limitations of this approach, including how metabolism and tissue synthesis impact the isotopic values of individual AAs and subsequent multivariate patterns. We measured carbon isotope (δ13C) values of essential (AAESS) and nonessential (AANESS) AAs in bone collagen, whisker, muscle, and liver from ten southern sea otters (Enhydra lutris nereis) that stranded in Monterey Bay, California. Sea otters in this population exhibit high degrees of individual dietary specialization, making this an excellent dataset to explore differences in AA δ13C values among tissues in a wild population. We found the δ13C values of the AANESS glutamic acid, proline, serine, and glycine and the AAESS threonine differed significantly among tissues, indicating possible isotopic discrimination during tissue synthesis. Threonine δ13C values were higher in liver relative to bone collagen and muscle, which may indicate catabolism of threonine for gluconeogenesis, an interpretation further supported by correlations between the δ13C values of threonine and its gluconeogenic products glycine and serine in liver. This intraindividual isotopic variation yielded different ecological interpretations among tissues; for 6/10 of the sea otter individuals analyzed, at least one tissue indicated reliance on a different primary producer source than the other tissues. Our results highlight the importance of gluconeogenesis in a carnivorous marine mammal and indicate that metabolic processes influence AAESS and AANESSδ13C values and multivariate AA δ13C patterns. [ABSTRACT FROM AUTHOR]

Hybridization between species affects biodiversity and population sustainability in numerous ways, many of which depend on the fitness of the hybrid relative to the parental species. Hybrids can exhibit fitter phenotypes compared to the parental lineages, and this 'hybrid vigour' can then lead to the extinction of one or both parental lines.In this study, we analysed the relationship between water loss and gas exchange to compare physiological performance among three tiger salamander genotypes—the native California tiger salamander (CTS), the invasive barred tiger salamanders (BTS) and CTS × BTS hybrids across multiple temperatures (13.5°C, 20.5°C and 23.5°C). We developed a new index of performance, the water‐gas exchange ratio (WGER), which we define as the ratio of gas exchange to evaporative water loss (μL VO2/μL H2O). The ratio describes the ability of an organism to support energetically costly activities with high levels of gas exchange while simultaneously limiting water loss to lower desiccation risk. We used flow through respirometry to measure the thermal sensitivity of metabolic rate and resistance to water loss of each salamander genotype to compare indices of physiological performance.We found that temperature had a significant effect on metabolic rate and resistance to water loss, with both traits increasing as temperatures warmed. Across genotypes, we found that hybrids have a higher WGER than the native CTS, owing to a higher metabolic rate despite having a lower resistance to water loss.These results provide a greater insight into the physiological mechanisms driving hybrid vigour and offer a potential explanation for the rapid spread of salamander hybrids. More broadly, our introduction of the WGER may allow for species‐ or lineage‐wide comparisons of physiological performance across changing environmental conditions, highlighting the insight that can be gleaned from multitrait analysis of organism performance. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

As small-bodied terrestrial organisms, insects face severe desiccation risks in arid environments, and these risks are increasing under climate change. Here, we investigate the physiological, chemical, and behavioral mechanisms by which harvester ants, one of the most abundant arid-adapted insect groups, cope with desiccating environmental conditions. We aimed to understand how body size, cuticular hydrocarbon profiles, and queen number impact worker desiccation resistance in the facultatively polygynous harvester ant, Pogonomyrmex californicus. We measured survival at 0% humidity of field-collected worker ants sourced from three closely situated populations within a semi-arid region of southern California. These populations vary in queen number, with one population dominated by multi-queen colonies (primary polygyny), one population dominated by single-queen colonies, and one containing an even mix of single- and multi-queen colonies. We found no effect of population on worker survival in desiccation assays, suggesting that queen number does not influence colony desiccation resistance. Across populations, however, body mass and cuticular hydrocarbon profiles significantly predicted desiccation resistance. Larger-bodied workers survived longer in desiccation assays, emphasizing the importance of reduced surface area-to-volume ratios in maintaining water balance. Additionally, we observed a positive relationship between desiccation resistance and the abundance of n-alkanes, supporting previous work that has linked these high-melting point compounds to improved body water conservation. Together, these results contribute to an emerging model explaining the physiological mechanisms of desiccation resistance in insects. [ABSTRACT FROM AUTHOR]

In light of ongoing environmental change, understanding the complex impact of interacting stressors on species, communities, and ecosystems is an important challenge. Many studies to date examine the effects of potential stressors on a single species of concern. Yet these effects often resonate throughout a community and may produce changes in ecosystem dynamics that are equally critical to species resilience. The aim of this study was to develop a mechanistic understanding of how a rapidly changing stressor, water temperature, will alter trophic interactions among ectothermic fish species. In our region, California's Sacramento–San Joaquin River Delta system, it has been speculated that the decreased survivorship of juvenile Chinook salmon (Oncorhynchus tshawytscha) in warming waters may be caused partly by increased predation. Temperature influences metabolic rate functions and the amount of energy available for fitness‐relevant parameters (i.e., swim performance and escape response). Consequently, we hypothesized that these patterns of predation emerge due to a physiological advantage of predators over prey at warmer temperatures. To explore this, our first objective was to determine the fundamental thermal physiology of juvenile Chinook salmon and their potential predators in the Delta. Three physiological performance traits were measured for each species across a spectrum of temperatures: aerobic scope, burst speed, and the ability to burst repeatedly. For our second objective, we assessed whether the effect of temperature on these performance traits predicted the outcome of predation trials conducted across the same temperature spectrum. We found that temperature effects were species or population specific. Additionally, absolute burst swimming ability and the relative burst performance between predator and prey were stronger indicators of trophic dynamics than aerobic scope. Our analyses also confirmed that a major predator in the Delta, specifically largemouth bass (Micropterus salmoides), is more thermally adapted to higher temperatures and will likely consume salmon with an increasing frequency as waters warm. Thus, we show that an improved understanding of how fundamental thermal physiology impacts predation can provide ecosystem managers with better tools to predictively model predation upon juvenile salmon based on prevailing and future water temperatures. [ABSTRACT FROM AUTHOR]

Accurately predicting the effects of future warming on aquatic ectotherms requires an understanding how thermal history, including average temperature and variation, affects populations of the same species. However, many laboratory studies simplify the thermal environment to focus on specific organismal responses and sacrifice environmental realism. Here, we paired laboratory-based transcriptomic RNA-seq analysis to identify thermally responsive genes with NanoString analysis of a subset of those genes to characterize natural field-based variation in thermal physiology among populations. We tested gene expression responses of three populations of field-acclimatized larval caddisflies (Dicosmoecus gilvipes) from streams in different eco-regions (mountain, valley, and coast) following exposure to current and future summertime temperatures. We hypothesized that distinct thermal histories across eco-regions could differentiate populations at baseline "control" levels of gene expression, as well as gene expression changes in response to dailywarming and heat shock. Population-specific patterns of gene expression were apparent under the control and daily warming conditions suggesting that local acclimatization or local adaptation may differentiate populations, while responses to extreme temperatures were similar across populations, indicating that response to thermal stress is canalized. Underlying gene co-expression patterns in the daily warming and heat shock treatments were different, demonstrating the distinct physiological mechanisms involved with thermal acclimatization and response to thermal stress. These results highlight the importance and limitations of studies of the thermal biology of wild-caught organisms in their natural environment, and provide an important resource for researchers of caddisflies and aquatic insects in general. [ABSTRACT FROM AUTHOR]

Coastal hypoxia threatens estuarine nursery habitat for juvenile demersal fishes worldwide, and is expected to intensify with climate change. This study examines the physiological tolerances of hypoxia in two ecologically and economically important flatfish species that co-occur in a highly eutrophic estuary and biodiversity hotspot on California's central coast, the Elkhorn Slough. Juveniles of English sole (Parophrys vetulus) occur less frequently in areas of the slough where dissolved oxygen (DO) ≤ 4.0 mg/L O 2 compared to speckled sanddabs (Citharichthys stigmaeus), suggesting that English sole may be more sensitive to hypoxia. We exposed both species to an ecologically relevant, acute six-hour exposure to six DO levels ranging from ambient to severely hypoxic: 8.0, 6.0, 4.0, 3.0, 2.0, and 1.5 mg/L O 2 and measured known physiological and biochemical indicators of hypoxia stress. As DO declined, metabolic rate and aerobic scope decreased for English sole, while anaerobic activity (measured by L-lactate) and ventilation rate increased for both species. Biochemical responses to hypoxia were observed only at very low DO levels (≤ 4.0 mg/L O 2), indicating that both species appear to have a higher tolerance for relatively short-term hypoxia than other teleost fishes. Speckled sanddabs increased ventilation rate and anaerobic activity at higher DO levels than English sole, suggesting that earlier onset of compensatory mechanisms may contribute to the greater relative hypoxia tolerance in sanddabs. Examining the link between physiological and ecological thresholds for hypoxia tolerance will help determine suitable nursery habitat areas and management targets for estuarine restoration, and aid in predictions of fishery success under eutrophication and climate change. • English sole and speckled sanddabs display high tolerance for short-term hypoxia. • Speckled sanddabs may demonstrate greater hypoxia tolerance than English sole. • English sole display greater interindividual variation in response to hypoxia. • Metabolic rate and aerobic scope decline with decreasing dissolved oxygen. • Anaerobic activity and ventilation rate increase with decreasing dissolved oxygen. [ABSTRACT FROM AUTHOR]

Adaptive responses to climate change, based on heritable variation in stress tolerance, may be important for plant population persistence. It is unclear which populations will mount the strongest future adaptive responses. It may be fruitful to identify populations that have escaped trade-offs among performance traits, which can hinder adaptation. Barring strong genetic constraints, the extent of trade-offs may depend on spatial relationships among climate variables shaping different traits. Here, we test for climate-driven ecotypic variation and trade-offs among drought and freezing sensitivity, and growth, for Lemmon's willow (Salix lemmonii) in a common garden study of 90 genotypes from 38 sites in the Sierra Nevada, USA. Salix lemmonii exhibits ecotypic variation in leaf turgor loss point, a measure of drought sensitivity, from -0.95 to -0.74 MPa along a gradient of spring snowpack. We also find variation in spring freezing sensitivity with minimum May temperature. However, we find no trade-off, as the climatic gradients shaping these traits are spatially uncorrelated in our study region, despite being negatively correlated across the Sierra Nevada. Species may escape adaptive trade-offs in geographic regions where climate variables are spatially decoupled. These regions may represent valuable reservoirs of heritable adaptive phenotypic variation., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Intraspecific variation in external and internal pigmentation is common among fishes and explained by a variety of biological and ecological factors. Blue-colored flesh in fishes is relatively rare but has been documented in some species of the sculpin, greenling, and perch families. Diet, starvation, photoprotection, and camouflage have all been suggested as proximate mechanisms driving blue flesh, but causal factors are poorly understood. We evaluated the relative importance of biological and spatial factors that could explain variation in blue coloration in 2021 lingcod (Ophiodon elongatus) captured across their range in the northeastern Pacific, from southeast Alaska to southern California. The probability of having blue flesh was highest for fish that were female, caught in shallower water, and smaller in body size. The incidence of blueness varied by region (4–25% of all fish) but was also confounded by differences in sex ratios of fish caught among regions. We analyzed the multivariate fatty acid composition of a subset of 175 fish from across the sampling range to test for differences in trophic biomarkers in blue lingcod. Lingcod fatty acid composition differed between regions and flesh colors but not between sexes. Blue-fleshed fish had lower concentrations of total fatty acids, 18:1ω-9, 16:1ω-7, 18:1ω-7, and ω-6 fatty acids, suggesting differences in energetics and energy storage in blue fish. While our data indicate potential links between diet and blue flesh in lingcod, important questions remain about the physiological mechanisms governing blueness and its biological consequences. [ABSTRACT FROM AUTHOR]

Most of our knowledge on reproductive biology of gray whales dates back to scientific research conducted during commercial whaling in the late 1950s and 1960s. The goal of the present study was to provide updated insights on reproductive physiology of gray whales, using progesterone and testosterone as biomarkers. We measured hormone concentrations using enzyme immunoassay (EIA) techniques in blubber biopsies collected from 106 individual whales from March to November over a span of 12 years (2004–2016) between California and Alaska. We found testosterone concentrations in males to increase significantly with age (P = 0.03). Adult males showed significantly elevated testosterone concentrations when sampled in the fall compared to the summer (P = 0.01), likely indicating physiological preparation for mating. We measured testosterone concentrations in females of different age classes, but no statistical differences were found. We found significantly higher progesterone concentrations in pregnant females compared to non-pregnant females and adult males (P< 0.001), indicating progesterone is a valid biomarker for pregnancy in gray whales. Both female and male calves had elevated progesterone concentrations, suggesting maternal transfer via lactation. We fit a mixture of two normal distributions to progesterone data from all non-calf females to identify clusters of high and low progesterone and estimated the probability of being pregnant for whales of unknown reproductive status. With this approach we identified likely pregnant and non-pregnant animals. This study represents an important milestone on reproductive profiles in this population, that can be used to estimate more accurate and precise reproductive parameters to be used for better understanding population dynamics of gray whales. [ABSTRACT FROM AUTHOR]

Facial gingival tissue thickness (FGTT) is important for an esthetically pleasing anterior restoration since it determines the soft tissue's ability to conceal the underlying restorative material. The purpose of this study was to investigate the change in FGTT after immediate implant placement and provisionalization with and without a connective tissue graft. Patients with a failing maxillary anterior tooth planned for immediate implant placement and provisionalization with (CT group) or without (NCT group) a subepithelial connective tissue graft were included in this study. After tooth extraction, direct measurement of the FGTT was performed; subsequent measurements were performed at the time of definitive prosthesis placement. Data were analyzed using independent and paired t tests at a significance level of α = .05. There was no statistically significant difference in the mean FGTT at tooth extraction between the CT and NCT groups. At prosthesis delivery, the mean FGTT for the CT group was significantly greater than that of the NCT group. The mean FGTT of both groups at prosthesis delivery was significantly higher than that at tooth extraction. The mean change in FGTT in the CT group was also significantly greater than that in the NCT group. Immediate implant placement and provisionalization in conjunction with a connective tissue graft is more likely to result in sufficient peri-implant tissue thickness to conceal underlying implant restorative materials than when performed without a connective tissue graft. [ABSTRACT FROM AUTHOR]

In tall conifers, leaf structure can vary dramatically with height due to decreasing water potential (Ψ) and increasing light availability. This variation in leaf structure can have physiological consequences such as increased respiratory costs, reduced internal carbon dioxide conductance rates and ultimately reduced maximum photosynthetic rates (A max). In Picea sitchensis (Bong.) Carrière, the leaf structure varies along the vertical gradient in ways that suggest compensatory changes to enhance photosynthesis, and this variation seems to be driven largely by light availability rather than by Ψ. These trends in leaf structure coupled with remarkably fast growth rates and dependence on moist environments inspire two important questions about P. sitchensis : (i) does foliar water uptake minimize the adverse effects of decreasing Ψ with height on leaf structure, and (ii) do trends in leaf structure increase photosynthetic rates despite increasing height? To answer these questions, we measured foliar water uptake capacity, predawn (Ψpd) and midday water potential and gas-exchange rates as they varied between 25- and 89-m heights in 300-year-old P. sitchensis trees in northwestern California. Our major findings for P. sitchensis include the following: (i) foliar water uptake capacity was quite high relative to published values for other woody species; (ii) foliar water uptake capacity increased between the crown base and treetop; (iii) wet season Ψpd was higher than predicted by the gravitational potential gradient, indicating foliar water uptake; and (iv) the maximum photosynthetic rate increased with height, presumably due to shifts in leaf structure between the crown base and treetop, mitigating height-related decreases in A max. These findings suggest that together, the use of fog, dew and rain deposits on leaves and shifts in the leaf structure to conserve and possibly enhance photosynthetic capacity likely contribute to the rapid growth rates measured in this species. [ABSTRACT FROM AUTHOR]

Agricultural activity, urban development and habitat alteration have caused the disappearance of the western spadefoot (Spea hammondii) from 80% of its geographic range in southern California. Despite the western spadefoot’s continuing decline, little research has been conducted on its natural history. The home range of adult spadefoots is unknown, and their use of upland habitat is poorly understood. Both factors are important for the long-term conservation of the species because adult spadefoots spend the majority of their lives away from breeding pools in self-excavated burrows. Between January 2012 and January 2013, we surgically implanted radio transmitters in 15 spadefoots at two locations and recorded their movements and habitat use. The mean distance moved between burrow locations was 18 m (SD ± 24.1 m, range1–204 m). The mean distance of burrows from the breeding pools was 40 m (SD ± 37.42 m, range 1–262 m). Rain was a significant predictor of spadefoot movement, with more rain predicting higher probability of movement and larger distances moved. At remote sensing scale (1 m) spadefoots selected grassland habitat for their burrow locations. At the microsite scale (< 1 m) spadefoots strongly selected duff over grass or shrub cover. Spadefoots burrowed in friable, sandy/loam soil with significantly less clay than random pseudoabsence points. This research enhances our understanding of a little-studied species and will contribute to the development of effective management plans for the western spadefoot. [ABSTRACT FROM AUTHOR]

Context: The Bodyblade Pro is used for shoulder rehabilitation after injury. Resistance is provided by blade oscillations-faster oscillations or higher speeds correspond to greater resistance. However, research supporting the Bodyblade Pro's use is scarce, particularly in comparison with dumbbell training. Objective: To compare muscle activity, using electromyography (EMG), in the back and shoulder regions during shoulder exercises with the Bodyblade Pro vs dumbbells. Design: Randomized crossover study. Setting: San Diego State University biomechanics laboratory. Participants: 11 healthy male subjects age 19-32 y. Intervention: Subjects performed shoulder-flexion and -abduction exercises using a Bodyblade Pro and dumbbells (5, 8, and 10 lb) while EMG recorded activity of the deltoid, pectoralis major, infraspinatus, serratus anterior, and erector spinae. Main Outcome Measures: Average peak muscle activity (% maximum voluntary isometric contraction) was separately measured for shoulder abduction and flexion in the range of 85° to 95°. Differences among exercise devices were separately analyzed for the flexed and abducted positions using 1-way repeated-measures ANOVA. Results: The Bodyblade Pro produced greater muscle activity than all the dumbbell trials. Differences were significant for all muscles measured (all P < .01) except for the erector spinae during shoulder flexion with a 10-lb dumbbell. EMG activity for the Bodyblade Pro exceeded 50% of the MVIC during both shoulder flexion and abduction. For the dumbbell conditions, only the 10-lb trials approached this effect. Conclusions: Using a Bodyblade during shoulder exercises results in greater shoulder- and back-muscle recruitment than dumbbells. The Bodyblade Pro can activate multiple muscles in a single exercise and thereby minimize the need for multiple dumbbell exercises. The Bodyblade Pro is an effective device for shoulder- and back-muscle activation that warrants further use by clinicians interested in its use for rehabilitation. [ABSTRACT FROM AUTHOR]

The article discusses californios' use of dance to prepare for war against Native Americans in Spanish and Mexican California. The author explains that apart from war, dance was an important aspect of californio culture. It is argued that the rhythmic skills, balance, and bodily control imparted to people from dancing could be beneficial to soldiers in battle. Types of dance discussed include the waltz and El Jarabe.

Objective: To determine recent trends in maternal prepregnancy body mass index (BMI) and to quantify its association with birth and maternal outcomes. Methods: A population-based retrospective cohort study included resident women with singleton births in the California Birth Statistical Master Files (BSMF) database from 2007 to 2016. There were 4,621,082 women included out of 5,054,968 women registered in the database. 433,886 (8.6%) women were excluded due to invalid or missing information for BMI. Exposures were underweight (BMI < 18.5 kg/m2), normal weight (18.5–24.9 kg/m2), overweight (25.0–29.9 kg/m2), and obese (≥ 30 kg/m2) at the onset of pregnancy. Obesity was subcategorized into class I (30.0–34.9 kg/m2), class II (35.0–39.9 kg/m2), and class III (≥ 40 kg/m2), while adverse outcomes examined were low birth weight (LBW), very low birth weight (VLBW), macrosomic births, preterm birth (PTB), very preterm birth (VPTB), small-for-gestational-age birth (SGA), large-for-gestational-age birth (LGA), and cesarean delivery (CD). Descriptive analysis, simple linear regression, and multivariate logistic regression were performed, and adjusted odds ratios (AORs) with 95% confidence intervals (CIs) for associations were estimated. Results: Over the ten-year study period, the prevalence of underweight and normal weight women at time of birth declined by 10.6% and 9.7%, respectively, while the prevalence of overweight and obese increased by 4.3% and 22.9%, respectively. VLBW increased significantly with increasing BMI, by 24% in overweight women and by 76% in women with class III obesity from 2007 to 2016. Women with class III obesity also had a significant increase in macrosomic birth (170%) and were more likely to deliver PTB (33%), VPTB (66%), LGA (231%), and CD (208%) than women with a normal BMI. However, obese women were less likely to have SGA infants; underweight women were 51% more likely to have SGA infants than women with a normal BMI. Conclusions: In California from 2007 to 2016, there was a declining trend in women with prepregnancy normal weight, and a rising trend in overweight and obese women, particularly obesity class III. Both extremes of prepregnancy BMI were associated with an increased incidence of adverse neonatal outcomes; however, the worse outcomes were prominent in those women classified as obese. [ABSTRACT FROM AUTHOR]

BACKGROUND: ARDS is a highly morbid condition characterized by diffuse pulmonary inflammation, which results in hypoxemic respiratory failure. Approximately 25% of patients with ARDS develop right ventricular dysfunction, with cor pulmonale being a common final pathway in a significant number of non-survivors. ARDS-related right ventricular dysfunction occurs due to acute elevation in ventricular afterload caused by mechanisms that are associated with increased pulmonary dead space fraction. Thus, we hypothesized that changes in pulmonary dead space fraction may reflect changes in pulmonary hemodynamics. METHODS: This was a prospective single-center study of 21 subjects with ARDS who underwent serial determination of pulmonary dead space fraction and pulmonary hemodynamics via transthoracic echocardiography. Linear mixed-effects modeling was performed to test for an association between a change in pulmonary dead space and a change in pulmonary hemodynamics. RESULTS: The tricuspid regurgitation velocity to right ventricular outflow track velocity time integral ratio, an echocardiographic surrogate for pulmonary vascular resistance, increased by 0.16 Wood units (Coefficient 0.16, 95% CI 0.09 - 0.23; P < .001), and the tricuspid regurgitation pressure gradient increased by 3.7 mm Hg (Coefficient 3.7, 95% CI 1.74 -5.63, P < .001) for every 10% increase in pulmonary dead space fraction. CONCLUSIONS: Increases in the pulmonary dead space fraction were associated with relative increases in both the tricuspid regurgitation velocity to right ventricular outflow track velocity time integral ratio and the tricuspid regurgitation pressure gradient, which likely contributed to the high incidence of ARDS-related right ventricular dysfunction encountered in clinical practice. Pulmonary dead space monitoring may serve as a clinical indicator to identify patients with ARDS at risk of developing right ventricular dysfunction and acute cor pulmonale. [ABSTRACT FROM AUTHOR]

Increased drought frequency and intensity and agricultural intensification have been key stressors to ecological systems over the past century. Biological proxies (e.g., pollen, tree rings) have been used to track this environmental change; however, linking these changes to the ecology of organisms remains challenging. Here, we link historical drought records to conditions of high water-stress in grassland habitats through the stable isotope analysis of California vole museum specimens (Microtus californicus). Using museum collections spanning 118-years (1891–2009), isotope values of dated hair tissues were associated with statewide drought metrics on the Palmer Drought Severity Index. We observed a positive correlation between δ15N and δ18O values and drought severity. The range in δ15N values (~ 18‰) is greater than what would be expected as a result of dietary shifts across the landscape (~ 3‰), and is likely attributed to the combined effects of physiological responses of M. californicus and isotopic shifts in plant resources with increased water-stress. Geospatial patterns in δ34S values of hair tissues reflect higher baseline isotope values in coastal habitats. However, comparably high δ34S values in the southern-most inland localities suggest sulfur fertilization of croplands and subsequent transfer to surrounding grassland habitats in 34S enriched forms. A broad δ13C range (− 28.7 to − 14.3‰) further suggests the consumption of C3 and C4 plant-based dietary proteins. As shown here, stable isotope analysis of museum collections can provide a climate and land use record based on the physiological performance and ecology of a study species in a region affected intensely by anthropogenic activities. [ABSTRACT FROM AUTHOR]

The objective of this clinical trial was to evaluate the effectiveness of zinc supplementation on diarrhea and average daily weight gain (ADG) in pre-weaned dairy calves. A total of 1,482 healthy Holstein heifer and bull calves from a large California dairy were enrolled at 24 to 48 hours of age until hutch exit at approximately 90 days of age. Calves were block-randomized by time to one of three treatments: 1) placebo, 2) zinc methionine (ZM), or 3) zinc sulfate (ZS) administered in milk once daily for 14 days. Serum total protein at enrollment and body weight at birth, treatment end, and hutch exit were measured. Fecal consistency was assessed daily for 28 days post-enrollment. For a random sample of 127 calves, serum zinc concentrations before and after treatment and a fecal antigen ELISA at diarrhea start and resolution for Escherichia coli K99, rotavirus, coronavirus, and Cryptosporidium parvum were performed. Linear regression showed that ZM-treated bull calves had 22 g increased ADG compared to placebo-treated bulls (P = 0.042). ZM-treated heifers had 9 g decreased ADG compared to placebo-treated heifers (P = 0.037), after adjusting for average birth weight. Sex-stratified models showed that high birth weight heifers treated with ZM gained more than placebo-treated heifers of the same birth weight, which suggests a dose-response effect rather than a true sex-specific effect of ZM on ADG. Cox regression showed that ZM and ZS-treated calves had a 14.7% (P = 0.015) and 13.9% (P = 0.022) reduced hazard of diarrhea, respectively, compared to placebo-treated calves. Calves supplemented for at least the first five days of diarrhea with ZM and ZS had a 21.4% (P = 0.027) and 13.0% (P = 0.040) increased hazard of cure from diarrhea, respectively, compared to placebo-treated calves. Logistic regression showed that the odds of microbiological cure at diarrhea resolution for rotavirus, C. parvum, or any single fecal pathogen was not different between treatment groups. Zinc supplementation delayed diarrhea and expedited diarrhea recovery in pre-weaned calves. Additionally, zinc improved weight gain differentially in bulls compared to heifers, indicating a research need for sex-specific dosing. [ABSTRACT FROM AUTHOR]