Manganese concentration affects chloroplast structure and the photosynthetic apparatus in Marchantia polymorpha.

Manganese (Mn) is an essential metal for plant growth. The most important Mn-containing enzyme is the Mn4CaO5 cluster that catalyzes water oxidation in photosystem II (PSII). Mn deficiency primarily affects photosynthesis, whereas Mn excess is generally toxic. Here, we studied Mn excess and deficiency in the liverwort Marchantia polymorpha, an emerging model ideally suited for analysis of metal stress since it accumulates rapidly toxic substances due to the absence of well-developed vascular and radicular systems and a reduced cuticle. We established growth conditions for Mn excess and deficiency and analyzed the metal content in thalli and isolated chloroplasts. In vivo super-resolution fluorescence microscopy and transmission electron microscopy revealed changes in the organization of the thylakoid membrane under Mn excess and deficiency. Both Mn excess and Mn deficiency increased the stacking of the thylakoid membrane. We investigated photosynthetic performance by measuring chlorophyll fluorescence at room temperature and 77 K, measuring P700 absorbance, and studying the susceptibility of thalli to photoinhibition. Nonoptimal Mn concentrations changed the ratio of PSI to PSII. Upon Mn deficiency, higher non-photochemical quenching was observed, electron donation to PSI was favored, and PSII was less susceptible to photoinhibition. Mn deficiency seemed to favor cyclic electron flow around PSI, thereby protecting PSII in high light. The results presented here suggest an important role of Mn in the organization of the thylakoid membrane and photosynthetic electron transport.

Compassionate reappraisal and rumination impact forgiveness, emotion, sleep, and prosocial accountability.

Sufficient sleep quality and quantity are important for biopsychosocial well-being. Correlational research has linked trait forgiveness to better sleep. Prior experimental evidence also demonstrated contrasting effects of offense rumination versus compassionate reappraisal on forgiveness and psychophysiological responses, suggesting the value of testing effects on sleep. The present study assessed 180 participants (90 M, 90 F). First, we replicated an individual difference model of forgiveness, rumination, depressed and anxious affect, and sleep. Second, we conducted a quasi-experiment inducing offense rumination and compassionate reappraisal on two consecutive nights. Compassionate reappraisal (vs. rumination) replicated past research by prompting more empathic, forgiving, positive, and social responses, with less negative emotion including anger. New findings revealed that compassionate reappraisal (vs. rumination) was also associated with faster sleep onset, fewer sleep disturbances, and fewer sleep impairing offense intrusions. The morning after compassionate reappraisal, participants reported less rumination and intrusive impact of the offense, with more hedonic well-being and accountability to others. Compared to rumination, compassionate reappraisal was associated with more empathy and forgiveness, better sleep, well-being, and prosociality.

Keep Your Mask On: The Benefits of Masking for Behavior and the Contributions of Aging and Disease on Dysfunctional Masking Pathways.

Environmental cues (e.g., light-dark cycle) have an immediate and direct effect on behavior, but these cues are also capable of "masking" the expression of the circadian pacemaker, depending on the type of cue presented, the time-of-day when they are presented, and the temporal niche of the organism. Masking is capable of complementing entrainment, the process by which an organism is synchronized to environmental cues, if the cues are presented at an expected or predictable time-of-day, but masking can also disrupt entrainment if the cues are presented at an inappropriate time-of-day. Therefore, masking is independent of but complementary to the biological circadian pacemaker that resides within the brain (i.e., suprachiasmatic nucleus) when exogenous stimuli are presented at predictable times of day. Importantly, environmental cues are capable of either inducing sleep or wakefulness depending on the organism's temporal niche; therefore, the same presentation of a stimulus can affect behavior quite differently in diurnal vs. nocturnal organisms. There is a growing literature examining the neural mechanisms underlying masking behavior based on the temporal niche of the organism. However, the importance of these mechanisms in governing the daily behaviors of mammals and the possible implications on human health have been gravely overlooked even as modern society enables the manipulation of these environmental cues. Recent publications have demonstrated that the effects of masking weakens significantly with old age resulting in deleterious effects on many behaviors, including sleep and wakefulness. This review will clearly outline the history, definition, and importance of masking, the environmental cues that induce the behavior, the neural mechanisms that drive them, and the possible implications for human health and medicine. New insights about how masking is affected by intrinsically photosensitive retinal ganglion cells, temporal niche, and age will be discussed as each relates to human health. The overarching goals of this review include highlighting the importance of masking in the expression of daily rhythms, elucidating the impact of aging, discussing the relationship between dysfunctional masking behavior and the development of sleep-related disorders, and considering the use of masking as a non-invasive treatment to help treat humans suffering from sleep-related disorders.

Impact of age on the circadian visual system and the sleep-wake cycle in mus musculus.

Age plays a critical role in disease development and tolerance to cancer treatment, often leading to an increased risk of developing negative symptoms including sleep disturbances. Circadian rhythms and sleep become disrupted as organisms age. In this study, we explored the behavioral alterations in sleep, circadian rhythms, and masking using a novel video system and interrogate the long-term impact of age-based changes in the non-image forming visual pathway on brain anatomy. We demonstrated the feasibility and utility of the novel system and establish that older mice have disruptions in sleep, circadian rhythms, and masking behaviors that were associated with major negative volume alterations in the non-imaging forming visual system, critical for the induction and rhythmic expression of sleep. These results provide important insights into a mechanism, showing brain atrophy is linked to age in distinct non-image forming visual regions, which may predispose older individuals to developing circadian and sleep dysfunction when further challenged by disease or treatment.

Volunteer Community Health and Agriculture Workers Help Reduce Childhood Malnutrition in Tajikistan.

Childhood malnutrition is a nationally-recognized problem in Tajikistan. In 2017, 6% of children under 5 years were wasted and 18% were stunted. Through the Tajikistan Health and Nutrition Activity (THNA), funded by the U.S. Agency for International Development's Feed the Future, IntraHealth International trained 1,370 volunteer community health workers (CHWs) and 500 community agricultural workers (CAWs) in 500 rural communities to improve nutrition among children and pregnant and breastfeeding women. CHWs and CAWs mutually encourage health behavior change, reinforce better agricultural practices, and promote maternal and child health and nutritious diets through household visits, community events, and peer support groups. CHWs refer children with malnutrition and diarrhea and pregnant women who are not registered for antenatal care to health facilities. THNA supported CHWs/CAWs through peer learning, refresher trainings, supportive supervision, and quarterly material incentives. We observed gains in knowledge, attitudes, and practices across health; nutrition; water, sanitation, and hygiene (WASH); and agriculture in target communities. From 2016 to 2019, we observed statistically significant (P<.05) improvements in children receiving a minimum acceptable diet; children with diarrhea receiving more liquids; women making 4 or more antenatal care visits; women reporting improved WASH; and farmers demonstrating improved agricultural practices. A February 2020 screening of 94.6% of children under 5 years in target communities found the prevalence of children with signs of wasting at 2.2%. Partnerships between CHWs, CAWs, and rural health workers facilitated these results. Paired agricultural and health interventions proved successful in improving nutrition of children and may be applicable in other contexts. Although effective in delivering interventions, CHWs/CAWs experience attrition, need motivation, and require intensive support. Assuming responsibility for this community-based volunteer workforce presents a major challenge for Tajikistan's national and local governments.

Pigment structure in the light-harvesting protein of the siphonous green alga Codium fragile.

The siphonaxanthin-siphonein-chlorophyll-a/b-binding protein (SCP), a trimeric light-harvesting complex isolated from photosystem II of the siphonous green alga Codium fragile, binds the carotenoid siphonaxanthin (Sx) and/or its ester siphonein in place of lutein, in addition to chlorophylls a/b and neoxanthin. SCP exhibits a higher content of chlorophyll b (Chl-b) than its counterpart in green plants, light-harvesting complex II (LHCII), increasing the relative absorption of blue-green light for photosynthesis. Using low temperature absorption and resonance Raman spectroscopies, we reveal the presence of two non-equivalent Sx molecules in SCP, and assign their absorption peaks at 501 and 535 nm. The red-absorbing Sx population exhibits a significant distortion that is reminiscent of lutein 2 in trimeric LHCII. Unexpected enhancement of the Raman modes of Chls-b in SCP allows an unequivocal description of seven to nine non-equivalent Chls-b, and six distinct Chl-a populations in this protein.

DEXMEDETOMIDINE, BUTORPHANOL, AND MIDAZOLAM AS A REVERSIBLE INDUCTION PROTOCOL IN NORTH AMERICAN RIVER OTTERS (LONTRA CANADENSIS).

Captured free-ranging North American river otters (Lontra canadensis) were immobilized for the placement of intra-abdominal radio transmitters in cooperation with the Iowa Department of Natural Resources. Twenty-four otters were induced with dexmedetomidine (0.03 mg/kg, IM), butorphanol (0.2 mg/kg, IM), and midazolam (0.15 mg/kg, IM) combined in one syringe. The otters were maintained on isoflurane during the surgical procedure. Heart rate and rhythm, respiratory rate, rectal temperature, and peripheral capillary oxygen saturation were recorded every 5 min for the duration of the procedures. The otters were reversed with atipamezole (0.3-2 mg/kg, IM), naltrexone (0.6 mg/kg, IM), and flumazenil (0.05 mg/kg, IM). Rapid and smooth induction was seen, with lateral recumbency reached within 6.2 ± 5.6 min. Episodes of resedation were seen in four otters that received 0.3 mg/kg atipamezole so the dose was increased to 1 mg/kg, and no further resedation events were noted. Two fatal complications occurred secondary to suspected respiratory arrest during recovery. This drug protocol provided a smooth and rapid induction in free-ranging river otters, but further research is required to determine the safety of this protocol for river otters in both zoo and free-ranging situations.

A Genetic Toolbox for the New Model Cyanobacterium Cyanothece PCC 7425: A Case Study for the Photosynthetic Production of Limonene.

Cyanobacteria, the largest phylum of prokaryotes, perform oxygenic photosynthesis and are regarded as the ancestors of the plant chloroplast and the purveyors of the oxygen and biomass that shaped the biosphere. Nowadays, cyanobacteria are attracting a growing interest in being able to use solar energy, H2O, CO2 and minerals to produce biotechnologically interesting chemicals. This often requires the introduction and expression of heterologous genes encoding the enzymes that are not present in natural cyanobacteria. However, only a handful of model strains with a well-established genetic system are being studied so far, leaving the vast biodiversity of cyanobacteria poorly understood and exploited. In this study, we focused on the robust unicellular cyanobacterium Cyanothece PCC 7425 that has many interesting attributes, such as large cell size; capacity to fix atmospheric nitrogen (under anaerobiosis) and to grow not only on nitrate but also on urea (a frequent pollutant) as the sole nitrogen source; capacity to form CO2-sequestrating intracellular calcium carbonate granules and to produce various biotechnologically interesting products. We demonstrate for the first time that RSF1010-derived plasmid vectors can be used for promoter analysis, as well as constitutive or temperature-controlled overproduction of proteins and analysis of their sub-cellular localization in Cyanothece PCC 7425. These findings are important because no gene manipulation system had been developed for Cyanothece PCC 7425, yet, handicapping its potential to serve as a model host. Furthermore, using this toolbox, we engineered Cyanothece PCC 7425 to produce the high-value terpene, limonene which has applications in biofuels, bioplastics, cosmetics, food and pharmaceutical industries. This is the first report of the engineering of a Cyanothece strain for the production of a chemical and the first demonstration that terpene can be produced by an engineered cyanobacterium growing on urea as the sole nitrogen source.

Immediate and Long-Term Implications of the COVID-19 Pandemic for People With Disabilities.

Some people with disabilities may have greater risk of contracting COVID-19 or experiencing worse outcomes if infected. Although COVID-19 is a genuine threat for people with disabilities, they also fear decisions that might limit lifesaving treatment should they contract the virus.During a pandemic, health systems must manage excess demand for treatment, and governments must enact heavy restrictions on their citizens to prevent transmission. Both actions can have a negative impact on people with disabilities.Ironically, the sociotechnical advances prompted by this pandemic could also revolutionize quality of life and participation for people with disabilities. Preparation for future disasters requires careful consideration.

Long-term management of congestive heart failure secondary to mitral stenosis in a ring-tailed lemur (Lemur catta).

CASE DESCRIPTION: A 15-year-old sexually intact female ring-tailed lemur (Lemur catta) was evaluated for a heart murmur and progressive radiographic cardiomegaly. CLINICAL FINDINGS: The lemur was clinically normal at the time of initial evaluation. Results of transthoracic echocardiography performed when the animal was anesthetized indicated mitral valve stenosis and severe left atrial dilation. Three months later, signs of left-sided congestive heart failure (CHF; coughing, exercise intolerance, and tachypnea) were observed and confirmed by the presence of radiographic pulmonary edema. TREATMENT AND OUTCOME: Medical treatment that consisted of aspirin, benazepril, furosemide, pimobendan, spironolactone, and ultimately torsemide in lieu of furosemide successfully controlled the lemur's clinical signs for 33 months after the development of CHF. Euthanasia was then elected on the basis of perceived poor quality of life because tachypnea became refractory to progressively higher dosages of diuretic. Necropsy confirmed mitral stenosis with severe left atrial dilation and chronic pulmonary congestion. CLINICAL RELEVANCE: The present report described the long-term medical management of CHF secondary to mitral stenosis in a lemur. Mitral stenosis was suspected to be a congenital defect, similar to the cause of mitral stenosis reported for dogs and cats, rather than to be an acquired change in association with rheumatic heart disease as commonly occurs for people. The lemur's CHF was well managed for 33 months with treatment, including pimobendan, which was well tolerated.

Developing outreach events that impact underrepresented students: Are we doing it right?

Many outreach programs share the common goals of serving underrepresented groups in STEM and improving public attitudes toward science. To meet these goals, scientists must find ways to both reach the appropriate audience and communicate the importance of science in meaningful and accessible ways. This requires careful consideration of the outreach method being used. Two common outreach methods include in-school visits (scientist in the classroom) and science fairs or open houses. Here, we compare the effectiveness of these two outreach methods in meeting the goals of reaching underrepresented students and/or students with less initial interest in science. We have found that in-school visits reached more underrepresented students and that initial attitudes toward science scores were lower for in-school visit participants than for open house event participants. Importantly, positive attitudes toward science increased significantly after in-school outreach events. Taken together, these data suggest that outreach events that are taken out into the community will reach a less enthusiastic but more diverse audience and can have a positive impact on attitudes toward science within these populations. These studies highlight the importance of knowing the goals of your outreach program and choosing the method that is best suited to meeting those goals.

IDENTIFICATION AND CORRELATION OF A NOVEL SIADENOVIRUS IN A FLOCK OF BUDGERIGARS (MELOPSITTACUS UNDULATES) INFECTED WITH SALMONELLA TYPHIMURIUM IN THE UNITED STATES.

A flock of budgerigars (Melopsittacus undulates) was purchased from a licensed breeder and quarantined at a zoologic facility within the United States in 2016. Following 82 deaths within the flock, the remaining 66 birds were depopulated because of ongoing clinical salmonellosis despite treatment. Gross necropsy was performed on all 66 birds. Histopathologic examination was performed on 10 birds identified with gross lesions and 10 birds without. Pathologic findings were most often observed in the liver, kidney, and spleen. Lesions noted in the livers and spleens were consistent with published reports of salmonellosis in psittacine species. Multisystemic changes associated with septicemia were not noted, most likely because of antibiotic intervention before euthanasia. Of the 20 budgerigars evaluated by histopathology, six had large basophilic intranuclear inclusion bodies within tubular epithelia in a portion of the kidneys. Electronic microscopy, next-generation sequencing, Sanger sequencing, and phylogenetic analyses were used to identify and categorize the identified virus as a novel siadenovirus strain BuAdV-1 USA-IA43444-2016. The strain was 99% similar to budgerigar adenovirus 1 (BuAdV-1), previously reported in Japan, and to a psittacine adenovirus 5 recently identified in a U.S. cockatiel. Salmonella typhimurium carriers were identified via polymerase chain reaction (PCR) and bacterial culture and compared with viral carriers identified via PCR. Inclusion bodies and Salmonella detection were significant in birds with gross lesions versus those without; however, there was no correlation between budgerigars positive with siadenovirus by PCR and concurrent Salmonella infection. Identifying subclinical siadenovirus strain BuAdV-1 USA-IA43444-2016 infection in this flock significantly differs from a previous report of clinical illness in five budgerigars resulting in death caused by BuAdV-1 in Japan. S. typhimurium remains a significant pathogen in budgerigars, and zoonotic concerns prompted depopulation to mitigate the public health risks of this flock.

Tuning antenna function through hydrogen bonds to chlorophyll a.

We describe a molecular mechanism tuning the functional properties of chlorophyll a (Chl-a) molecules in photosynthetic antenna proteins. Light-harvesting complexes from photosystem II in higher plants - specifically LHCII purified with α- or ß-dodecyl-maltoside, along with CP29 - were probed by low-temperature absorption and resonance Raman spectroscopies. We show that hydrogen bonding to the conjugated keto carbonyl group of protein-bound Chl-a tunes the energy of its Soret and Qy absorption transitions, inducing red-shifts that are proportional to the strength of the hydrogen bond involved. Chls-a with non-H-bonded keto C131 groups exhibit the blue-most absorption bands, while both transitions are progressively red-shifted with increasing hydrogen-bonding strength - by up 382 & 605 cm-1 in the Qy and Soret band, respectively. These hydrogen bonds thus tune the site energy of Chl-a in light-harvesting proteins, determining (at least in part) the cascade of energy transfer events in these complexes.

Editor choice: Let it rest: Sleep and health as positive correlates of forgiveness of others and self-forgiveness.

Objective: The present study examined forgiveness of others, self-forgiveness, sleep, and health in a nationally representative sample of United States adults. It was hypothesised that sleep would mediate the associations of forgiveness of others and self-forgiveness with health.Design: A nationally representative survey of 1,423 United States adults.Main Outcome Measures: Measures included forgiveness of others, self-forgiveness, sleep quantity, sleep quality, psychological distress, life satisfaction, and self-rated physical health.Results: Forgiveness of others (ß = .20, p < .001) and self-forgiveness (ß = .11, p < .01) were associated with sleep and forgiveness of others (ß = .24, p < .001) and self-forgiveness (ß = .27, p < .001) were associated with health. Sleep was associated with health (ß = .45, p < .001) and also acted as a mediator of the associations of forgiveness of others (ß = .09, p < .01) and self-forgiveness (ß = .05, p < .01) with health.Conclusions: Forgiveness of others and self-forgiveness may attenuate emotions such as anger, regret, and rumination and provide a buffer between one's own and others' offenses occurring during the day and offer a restful mental state that supports sound sleep which, in turn, is associated with better health.

Superior Colliculus Lesions Lead to Disrupted Responses to Light in Diurnal Grass Rats (Arvicanthis niloticus).

The circadian system regulates daily rhythms of physiology and behavior. Although extraordinary advances have been made to elucidate the brain mechanisms underlying the circadian system in nocturnal species, less is known in diurnal species. Recent studies have shown that retinorecipient brain areas such as the intergeniculate leaflet (IGL) and olivary pretectal nucleus (OPT) are critical for the display of normal patterns of daily activity in diurnal grass rats (Arvicanthis niloticus). Specifically, grass rats with IGL and OPT lesions respond to light in similar ways to intact nocturnal animals. Importantly, both the IGL and OPT project to one another in nocturnal species, and there is evidence that these 2 brain regions also project to the superior colliculus (SC). The SC receives direct retinal input, is involved in the triggering of rapid eye movement sleep in nocturnal rats, and is disproportionately large in the diurnal grass rat. The objective of the current study was to use diurnal grass rats to test the hypothesis that the SC is critical for the expression of diurnal behavior and physiology. We performed bilateral electrolytic lesions of the SC in female grass rats to examine behavioral patterns and acute responses to light. Most grass rats with SC lesions expressed significantly reduced activity in the presence of light. Exposing these grass rats to constant darkness reinstated activity levels during the subjective day, suggesting that light masks their ability to display a diurnal activity profile in 12:12 LD. Altogether, our data suggest that the SC is critical for maintaining normal responses to light in female grass rats.

Functional and anatomical variations in retinorecipient brain areas in Arvicanthis niloticus and Rattus norvegicus: implications for the circadian and masking systems.

Daily rhythms in light exposure influence the expression of behavior by entraining circadian rhythms and through its acute effects on behavior (i.e., masking). Importantly, these effects of light are dependent on the temporal niche of the organism; for diurnal organisms, light increases activity, whereas for nocturnal organisms, the opposite is true. Here we examined the functional and morphological differences between diurnal and nocturnal rodents in retinorecipient brain regions using Nile grass rats (Arvicanthis niloticus) and Sprague-Dawley (SD) rats (Rattus norvegicus), respectively. We established the presence of circadian rhythmicity in cFOS activation in retinorecipient brain regions in nocturnal and diurnal rodents housed in constant dark conditions to highlight different patterns between the temporal niches. We then assessed masking effects by comparing cFOS activation in constant darkness (DD) to that in a 12:12 light/dark (LD) cycle, confirming light responsiveness of these regions during times when masking occurs in nature. The intergeniculate leaflet (IGL) and olivary pretectal nucleus (OPN) exhibited significant variation among time points in DD of both species, but their expression profiles were not identical, as SD rats had very low expression levels for most timepoints. Light presentation in LD conditions induced clear rhythms in the IGL of SD rats but eliminated them in grass rats. Additionally, grass rats were the only species to demonstrate daily rhythms in LD for the habenula and showed a strong response to light in the superior colliculus. Structurally, we also analyzed the volumes of the visual brain regions using anatomical MRI, and we observed a significant increase in the relative size of several visual regions within diurnal grass rats, including the lateral geniculate nucleus, superior colliculus, and optic tract. Altogether, our results suggest that diurnal grass rats devote greater proportions of brain volume to visual regions than nocturnal rodents, and cFOS activation in these brain regions is dependent on temporal niche and lighting conditions.

An Effective Model for Engaging Faculty and Undergraduate Students in Neuroscience Outreach with Middle Schoolers.

Engaging undergraduate students in science outreach events is critical for improving future communication between scientists and community members. Outreach events are opportunities for faculty and undergraduates to utilize active learning strategies to engage non-scientists in scientific questions and principles. Through careful design of outreach events, undergraduate students can practice science communication skills while reaching populations of the public that remain underserved and underrepresented in scientific fields. Here we describe a classroom outreach event designed to give a broad overview of the field of neuroscience to middle school students of all backgrounds by delivering the content in school, during school hours. Through a variety of active learning strategies, middle school students learned about basic structures of the brain and their corresponding functions. Additionally, these students participated in demonstrations during which they generated and tested their own hypotheses and learned about sensory transmission and responses. We designed the lesson to meet the educational goals for middle school students, fulfilling the criteria for the Next Generation Science Standard MS-LS1-8 (NGSS Lead States, 2013). We evaluated the impact of the event on both undergraduate student instructors and middle school participants. Our results demonstrate that these outreach events effectively deliver new content to middle school students while also reinforcing the importance and value of outreach to undergraduate instructors.

Melanopsin-Containing ipRGCs Are Resistant to Excitotoxic Injury and Maintain Functional Non-Image Forming Behaviors After Insult in a Diurnal Rodent Model.

Intrinsically photosensitive retinal ganglion cells (ipRGCs) are critical for the light signaling properties of non-image forming vision. Melanopsin-expressing ipRGCs project to retinorecipient brain regions involved in modulating circadian rhythms. Melanopsin has been shown to play an important role in how animals respond to light, including photoentrainment, masking (i.e., acute behavioral responses to light), and the pupillary light reflex (PLR). Importantly, ipRGCs are resistant to various forms of damage, including ocular hypertension, optic nerve crush, and excitotoxicity via N-methyl-D-aspartic acid (NMDA) administration. Although these cells are resistant to various forms of injury, the question still remains whether or not these cells remain functional following injury. Here we tested the hypothesis that ipRGCs would be resistant to excitotoxic damage in a diurnal rodent model, the Nile grass rat (Arvicanthis niloticus). In addition, we hypothesized that following insult, grass rats would maintain normal circadian entrainment and masking to light. In order to test these hypotheses, we injected NMDA intraocularly and examined its effect on the survivability of ipRGCs and RGCs, along with testing behavioral and functional consequences. Similar to findings in nocturnal rodents, ipRGCs were spared from significant damage but RGCs were not. Importantly, whereas image-forming vision was significantly impaired, non-image forming vision (i.e, photoentrainment, masking, and PLR) remained functional. The present study aims to characterize the resistance of ipRGCs to excitotoxicity in a diurnal rodent model.

The effects of ambient temperature and lighting intensity on wheel-running behavior in a diurnal rodent, the Nile grass rat (Arvicanthis niloticus).

Environmental conditions, such as the light-dark cycle and temperature, affect the display of circadian rhythmicity and locomotor activity patterns in mammals. Here, we tested the hypothesis that manipulating these environmental conditions would affect wheel-running activity patterns in a diurnal rodent, the Nile grass rat (Arvicanthis niloticus). Grass rats are diurnal in the field, however, a subset switch from a day-active pattern to a night-active pattern of activity after the introduction of a running wheel. The mechanism of this chronotype switch remains largely unknown. In the present study, grass rats were presented with running wheels in 12:12 light-dark conditions. First, subjects were exposed to 25 °C during the day and 21 °C at night, which resulted in 100% of grass rats expressing diurnal behavior. Subjects were then exposed to manipulations of elevated ambient temperature, which resulted in a significant reduction in wheel-running activity. Reducing ambient temperature below 21 °C, however, did not disrupt the expression of diurnality or overall activity. Next, lighting intensity was reduced, which resulted in a switch from a diurnal to a nocturnal chronotype in a subset of animals and reduced overall wheel-running activity. Upon return to baseline lighting intensity, patterns of diurnal activity were restored. Altogether, increases in ambient temperature and decreases in lighting intensity significantly reduced overall wheel-running activity. Importantly, dim light resulted in a temporal niche switch in a subset of grass rats, suggesting a critical role for lighting intensity on the expression of wheel-running activity patterns. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

LESIONS OF THE FEMALE REPRODUCTIVE TRACT IN JAPANESE MACAQUE ( MACACA FUSCATA) FROM TWO CAPTIVE COLONIES.

Reproductive lesions have been described in various nonhuman primate species, including rhesus macaques ( Macaca mulatta), cynomolgus macaques ( Macaca fascicularis), baboons ( Papio spp.), squirrel monkeys ( Saimiri sciureus), and chimpanzees ( Pan spp.); however, there are few publications describing reproductive disease and pathology in Japanese macaques ( Macaca fuscata). A retrospective evaluation of postmortem reports for two captive M. fuscata populations housed within zoos from 1982 through 2015 was completed, comparing reproductive diseases diagnosed by gross pathology and histopathology. Disease prevalence, organs affected, and median age at death between the two institutions was also compared. Fifteen female captive M. fuscata, ranging in age from 15 to 29 yr were identified with reproductive tract lesions, including endometriosis, endometritis, leiomyoma, leiomyosarcoma, and adenomyosis. No significant differences were identified in disease prevalence, organs affected, and median age of death between the two institutions. Endometriosis was the most common disease process identified and was found in 10 of the 15 cases (66.7%), followed by leiomyoma (4 of 15; 26.7%). In four cases (26.7%), severe endometriosis and secondary hemorrhage was indicated as the cause of death or the primary reason for humane euthanasia. These findings were compared with a separate population of Japanese macaques managed within a research facility in the United States, with a prevalence of endometriosis of 7.6%. This study discusses possible risk factors and potential treatment options for the management of endometriosis in captive M. fuscata.