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1.
Phys Rev Lett ; 133(2): 022502, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39073976

RESUMO

The nuclear two-photon or double-gamma (2γ) decay is a second-order electromagnetic process whereby a nucleus in an excited state emits two gamma rays simultaneously. To be able to directly measure the 2γ decay rate in the low-energy regime below the electron-positron pair-creation threshold, we combined the isochronous mode of a storage ring with Schottky resonant cavities. The newly developed technique can be applied to isomers with excitation energies down to ∼100 keV and half-lives as short as ∼10 ms. The half-life for the 2γ decay of the first-excited 0^{+} state in bare ^{72}Ge ions was determined to be 23.9(6) ms, which strongly deviates from expectations.

2.
Nature ; 554(7691): 216-218, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29420479

RESUMO

The atomic nucleus and its electrons are often thought of as independent systems that are held together in the atom by their mutual attraction. Their interaction, however, leads to other important effects, such as providing an additional decay mode for excited nuclear states, whereby the nucleus releases energy by ejecting an atomic electron instead of by emitting a γ-ray. This 'internal conversion' has been known for about a hundred years and can be used to study nuclei and their interaction with their electrons. In the inverse process-nuclear excitation by electron capture (NEEC)-a free electron is captured into an atomic vacancy and can excite the nucleus to a higher-energy state, provided that the kinetic energy of the free electron plus the magnitude of its binding energy once captured matches the nuclear energy difference between the two states. NEEC was predicted in 1976 and has not hitherto been observed. Here we report evidence of NEEC in molybdenum-93 and determine the probability and cross-section for the process in a beam-based experimental scenario. Our results provide a standard for the assessment of theoretical models relevant to NEEC, which predict cross-sections that span many orders of magnitude. The greatest practical effect of the NEEC process may be on the survival of nuclei in stellar environments, in which it could excite isomers (that is, long-lived nuclear states) to shorter-lived states. Such excitations may reduce the abundance of the isotope after its production. This is an example of 'isomer depletion', which has been investigated previously through other reactions, but is used here to obtain evidence for NEEC.

3.
Anaesthesia ; 79(5): 486-497, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38359531

RESUMO

Disparities relating to postpartum recovery outcomes in different socio-economic and racial ethnic groups are underexplored. We conducted a planned analysis of a large prospective caesarean delivery cohort to explore the relationship between ethnicity, socio-economic status and postpartum recovery. Eligible patients were enrolled and baseline demographic, obstetric and medical history data were collected 18 h and 30 h following delivery. Patients completed postpartum quality of life and recovery measures in person on day 1 (EuroQoL EQ-5D-5L, including global health visual analogue scale; Obstetric Quality of Recovery-10 item score; and pain scores) and by telephone between day 28 and day 32 postpartum (EQ-5D-5L and pain scores). Socio-economic group was determined according to the Index of Multiple Deprivation quintile of each patient's usual place of residence. Data from 1000 patients who underwent caesarean delivery were included. There were more patients of Asian, Black and mixed ethnicity in the more deprived quintiles. Patients of White ethnicities had shorter postpartum duration of hospital stay compared with patients of Asian and Black ethnicities (35 (28-56 [18-513]) h vs. 44 (31-71 [19-465]) h vs. 49 (33-75 [23-189]) h, respectively. In adjusted models at day 30, patients of Asian ethnicity had a significantly greater risk of moderate to severe pain (numerical rating scale ≥ 4) at rest and on movement (odds ratio (95%CI) 2.42 (1.24-4.74) and 2.32 (1.40-3.87)), respectively). There were no differences in readmission rates or incidence of complications between groups. Patients from White ethnic backgrounds experience shorter postpartum duration of stay compared with patients from Asian and Black ethnic groups. Ethnic background impacts pain scores and recovery at day 1 postpartum and following hospital discharge, even after adjusting for socio-economic group. Further work is required to understand the underlying factors driving differences in pain and recovery and to develop strategies to reduce disparities in obstetric patients.


Assuntos
Etnicidade , Qualidade de Vida , Gravidez , Feminino , Humanos , Estudos Prospectivos , Cesárea , Período Pós-Parto , Pobreza , Dor
4.
Anaesthesia ; 78(9): 1071-1080, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37226593

RESUMO

To better understand outcomes in postpartum patients who receive peripartum anaesthetic interventions, we aimed to assess quality of recovery metrics following childbirth in a UK-based multicentre cohort study. This study was performed during a 2-week period in October 2021 to assess in- and outpatient post-delivery recovery at 1 and 30 days postpartum. The following outcomes were reported: obstetric quality of recovery 10-item measure (ObsQoR-10); EuroQoL (EQ-5D-5L) survey; global health visual analogue scale; postpartum pain scores at rest and movement; length of hospital stay; readmission rates; and self-reported complications. In total, 1638 patients were recruited and responses analysed from 1631 (99.6%) and 1282 patients (80%) at one and 30 days postpartum, respectively. Median (IQR [range]) length of stay postpartum was 39.3 (28.5-61.0 [17.7-513.4]), 40.3 (28.5-59.1 [17.8-220.9]), and 35.9 (27.1-54.1 [17.9-188.4]) h following caesarean, instrumental and vaginal deliveries, respectively. Median (IQR [range]) ObsQoR-10 score was 75 ([62-86] 4-100) on day 1, with the lowest ObsQoR-10 scores (worst recovery) reported by patients undergoing caesarean delivery. Of the 1282 patients, complications within the first 30 days postpartum were reported by 252 (19.7%) of all patients. Readmission to hospital within 30 days of discharge occurred in 69 patients (5.4%), with 49 (3%) for maternal reasons. These data can be used to inform patients regarding expected recovery trajectories; facilitate optimal discharge planning; and identify populations that may benefit most from targeted interventions to improve postpartum recovery experience.


Assuntos
Cesárea , Parto Obstétrico , Gravidez , Feminino , Humanos , Estudos de Coortes , Estudos Prospectivos , Cesárea/efeitos adversos , Período Pós-Parto
5.
Opt Express ; 30(17): 31182-31194, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242206

RESUMO

As commercially available glasses for color vision deficiency (CVD) are classified as low risk, they are not subject to stringent marketing regulations. We investigate how EnChroma and VINO glasses affect performance on the Colour Assessment and Diagnosis (CAD) test in individuals with CVD. Data were obtained from 51 individuals with red-green CVD. Blood or saliva samples were collected to examine the structure of the OPN1LW/OPN1MW array. Individuals completed the CAD test twice without glasses and once with each pair of glasses. Although there was a statistically significant effect of both glasses, only that of VINO could be considered functionally meaningful.


Assuntos
Doenças Cardiovasculares , Defeitos da Visão Cromática , Visão de Cores , Cor , Percepção de Cores , Defeitos da Visão Cromática/diagnóstico , Óculos , Humanos
7.
Breast Cancer Res Treat ; 190(2): 287-293, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34515905

RESUMO

PURPOSE: Older cancer survivors required medical care during the COVID-19 pandemic, but there are limited data on medical care in this age group. METHODS: We evaluated care disruptions in a longitudinal cohort of non-metastatic breast cancer survivors aged 60-98 from five US regions (n = 321). Survivors completed a web-based or telephone survey from May 27, 2020 to September 11, 2020. Care disruptions included interruptions in seeing or speaking to doctors, receiving medical treatment or supportive therapies, or filling prescriptions since the pandemic began. Logistic regression models evaluated associations between care disruptions and education, medical, psychosocial, and COVID-19-related factors. Multivariate models included age, county COVID-19 death rates, comorbidity, and post-diagnosis time. RESULTS: There was a high response rate (n = 262, 81.6%). Survivors were 32.2 months post-diagnosis (SD 17.5, range 4-73). Nearly half (48%) reported a medical disruption. The unadjusted odds of care disruptions were higher with each year of education (OR 1.22, 95% CI 1.08-1.37, p = < 0.001) and increased depression by CES-D score (OR 1.04, CI 1.003-1.08, p = 0.033) while increased tangible support decreased the odds of disruptions (OR 0.99, 95% CI 0.97-0.99, p = 0.012). There was a trend between disruptions and comorbidities (unadjusted OR 1.13 per comorbidity, 95% CI 0.99-1.29, p = 0.07). Adjusting for covariates, higher education years (OR1.23, 95% CI 1.09-1.39, p = 0.001) and tangible social support (OR 0.98 95% CI 0.97-1.00, p = 0.006) remained significantly associated with having care disruptions. CONCLUSION: Older breast cancer survivors reported high rates of medical care disruptions during the COVID-19 pandemic and psychosocial factors were associated with care disruptions. CLINICALTRIALS. GOV IDENTIFIER: NCT03451383.


Assuntos
Neoplasias da Mama , COVID-19 , Sobreviventes de Câncer , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
8.
Phys Rev Lett ; 127(4): 042501, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34355962

RESUMO

A novel approach for isomer depletion in ion-atom collisions is proposed and considered theoretically. Analyses are performed for the depletion of the ^{93m}Mo isomer for which an unexpectedly large probability was measured in the beam-based experiment of Chiara et al. [Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483]. The subsequent attempt at a theoretical description based on state-of-the-art atomic theory did not reproduce the experimental result [Wu et al., Phys. Rev. Lett. 122, 212501 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.212501] and showed a dramatic disagreement with the experiment (by many orders of magnitude). This conflict calls for further research on the nature of isomer depletion mechanisms occurring in atomic processes. Here, we propose to consider the ^{93m}Mo isomer depletion as the nuclear excitation by electron capture in resonant transfer process taking into account the momentum distribution of the target electrons. Although our results only slightly shift the upper theoretical limit for the total ^{93m}Mo isomer depletion probability toward the experimental value, they show the importance of considering the Compton profile in the theoretical description, in particular for the L shell, for which the depletion probability increases by many orders of magnitude.

9.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891447

RESUMO

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

12.
Pain Med ; 22(6): 1324-1332, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33594439

RESUMO

OBJECTIVE: To evaluate the feasibility and safety of hyperbaric oxygen therapy (HBOT) in patients with fibromyalgia (FM). DESIGN: A cohort study with a delayed treatment arm used as a comparator. SETTING: Hyperbaric Medicine Unit, Toronto General Hospital, Ontario, Canada. SUBJECTS: Eighteen patients diagnosed with FM according to the American College of Rheumatology and a score ≥60 on the Revised Fibromyalgia Impact Questionnaire. METHODS: Participants were randomized to receive immediate HBOT intervention (n = 9) or HBOT after a 12-week waiting period (n = 9). HBOT was delivered at 100% oxygen at 2.0 atmospheres per session, 5 days per week, for 8 weeks. Safety was evaluated by the frequency and severity of adverse effects reported by patients. Feasibility was assessed by recruitment, retention, and HBOT compliance rates. Both groups were assessed at baseline, after HBOT intervention, and at 3 months' follow-up. Validated assessment tools were used to evaluate pain, psychological variables, fatigue, and sleep quality. RESULTS: A total of 17 patients completed the study. One patient withdrew after randomization. HBOT-related adverse events included mild middle-ear barotrauma in three patients and new-onset myopia in four patients. The efficacy of HBOT was evident in most of the outcomes in both groups. This improvement was sustained at 3-month follow-up assessment. CONCLUSION: HBOT appears to be feasible and safe for individuals with FM. It is also associated with improved global functioning, reduced symptoms of anxiety and depression, and improved quality of sleep that was sustained at 3-month follow-up assessment.


Assuntos
Fibromialgia , Oxigenoterapia Hiperbárica , Estudos de Coortes , Fadiga , Fibromialgia/terapia , Humanos , Ontário
13.
J Opt Soc Am A Opt Image Sci Vis ; 38(10): 1400-1408, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34612970

RESUMO

The adaptive optics scanning light ophthalmoscope (AOSLO) allows cellular resolution imaging of the living retina. The accuracy of many quantitative measurements made from these images requires accurate estimates of the lateral scale of the images. Here, we used trial lenses, which are known to affect the relative magnification of the retinal image, to compare empirical measures of image scale with theoretical estimates from a four-surface optical model. The theoretical optical model overestimated the empirically determined change in image scale in 70% of the subjects examined, albeit to varying degrees. While the origin for the differences between subjects is not known, residual accommodation during imaging likely contributes to this variability in retinal magnification. These data provide an opportunity to derive improved lateral scaling error estimates for structural metrics extracted from AOSLO retinal images.


Assuntos
Oftalmoscópios , Retina , Humanos , Retina/diagnóstico por imagem
14.
Dis Aquat Organ ; 143: 37-50, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33506814

RESUMO

Studies of ectoparasites of wild-caught queenfish Scomberoides commersonnianus from several areas in northern Australia were reviewed to investigate relationships between parasite burdens, environmental conditions and external lesions. A sample of 27 queenfish captured near a dredge spoil disposal site in Gladstone Harbour, Queensland, Australia, in January 2012 was anomalous, with a high percentage of fish (66.6%) exhibiting grossly visible skin lesions including foci of erythema and petechial haemorrhages, particularly on the pectoral girdle and ventrolateral surfaces. Microscopically, lesions comprised acute epidermal erosion, ulceration and/or perivascular dermatitis with dermal oedema and depigmentation. Skin lesions were associated with high prevalence (100%) and intensity (mean = 21.2 copepods fish-1, range 4-46) of infection by sea lice Lepeophtheirus spinifer. Only queenfish infected with >10 L. spinifer presented with skin lesions. This is the first record of L. spinifer from Australia. In contrast, grossly visible skin lesions were not reported from queenfish (n = 152) sampled from other sites in the Northern Territory and Queensland, where the sampled fish had a much lower prevalence (51.3%) and intensity (mean = 3.54, range 0-26) of copepod (L. spinifer, Caligus spp. and Tuxophorus sp.) infections. Copepods from queenfish in studies undertaken outside Gladstone Harbour exhibited an over-dispersed pattern of infection, with the vast majority (n = 137, or 90.1%) of fish infected with <5 copepods. These data demonstrate that heavy L. spinifer infections, combined with poor water quality and/or direct exposure to contaminated dredge spoil and blooms of the cyanobacterium Lyngbya majuscula, can be associated with cutaneous disease in wild-caught queenfish.


Assuntos
Copépodes , Doenças dos Peixes , Perciformes , Animais , Austrália , Doenças dos Peixes/epidemiologia , Peixes , Queensland/epidemiologia
15.
J Hum Nutr Diet ; 33(1): 98-105, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31429508

RESUMO

BACKGROUND: In 2012, the National Institute for Health and Care Excellence (NICE) Clinical Guidelines for Epilepsies: Diagnosis and Management (CG137) included, for the first time, ketogenic diets (KDs) as a treatment option for drug-resistant paediatric epilepsy. The recommendation was made to refer children and young people with epilepsy whose seizures have not responded to appropriate anti-epileptic drugs to a tertiary paediatric epilepsy specialist for consideration of the use of KDs. We aimed to assess the impact of this change in guidance on the numbers of ketogenic centres and patients following KDs for epilepsy in the UK and Ireland. METHODS: An online survey was circulated to ketogenic dietitians from the UK and Ireland. The results were compared with similar surveys published in 2000 and 2010. RESULTS: The number of centres offering KDs for treatment of epilepsy has risen from 22 in 2000, to 28 in 2010, and to 39 in 2017 (77% overall increase). Seven of these centres accept adult referrals, in comparison to only two centres in 2010. Patient numbers have increased from 101 in 2000 to 754 in 2017. In total, 267 patients are waiting to commence KD at 31 centres. CONCLUSIONS: Over the last 7 years, the number of patients treated with a KD for epilepsy in the UK and Ireland has increased by 647%, with a 77% increase in the number of centres offering KDs. Despite this rapid growth, there is ongoing demand for patients to be considered for dietary therapy, highlighting the need for continued expansion of KD services nationally.


Assuntos
Dieta Cetogênica/normas , Epilepsia/dietoterapia , Política Nutricional/tendências , Nutricionistas/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Criança , Feminino , Humanos , Irlanda , Masculino , Reino Unido
16.
J Dairy Sci ; 103(7): 6612-6626, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32307158

RESUMO

Adrenal responsiveness was tested in nonpregnant, lactating Holstein dairy cows fed diets supplemented with OmniGen-AF (OG; Phibro Animal Health Corp., Teaneck, NJ), an immune modulator, and in nonsupplemented control (CON) cows following bolus infusions of a combination of corticotropin-releasing hormone (CRH; 0.3 µg/kg of BW) and arginine vasopressin (VP; 1.0 µg/kg of BW) or ACTH (0.1 IU/kg of BW) in 2 environments: thermoneutral [TN; temperature-humidity index (THI) <60] for 24 h/d and heat stress (HS; THI >68 for 17 h/d). Cows (506) were initially fed OG (n = 254) or CON (n = 252) diets for 44 d before selection of a subgroup of cows (n = 12; 6 OG, 6 CON) for the study. The 2 subgroups were balanced for parity, milk yield, and days in milk. All cows were transported to and housed in 2 environmentally controlled rooms at the University of Arizona Agricultural Research Complex (Tucson). Cows were given 3 d to acclimate to the rooms and then underwent 12 d of TN conditions and then 8 d of HS conditions for a total of 24 d on experiment. Cows were infused with CRH-VP on d 9 of TN and on d 1 of HS and with ACTH on d 10 of TN and on d 2 of HS. Hormone infusions took place at 1000 h (0 h) on each infusion day. Blood samples, taken in 30-min intervals, were first collected at 0800 h (-2 h) and were drawn until 1800 h (8 h). Before infusion, serum progesterone was elevated in OG cows compared with CON cows. Infusion of releasing factors (CRH-VP or ACTH) caused increases in serum cortisol and progesterone, but cortisol release was greater in CON cows than in OG cows during HS, whereas progesterone did not differ between the 2 treatments. Serum ACTH increased following infusion of releasing factors, but this increase was greater following CRH-VP infusion than ACTH infusion. Serum bovine corticosteroid-binding globulin also increased following infusion of releasing factors in both treatment groups, but this increase was greater during HS in cows fed OG. The free cortisol index (FCI) increased following CRH-VP and ACTH and was higher in HS than in TN for both OG and CON cows. However, the FCI response was blunted in OG cows compared with CON cows during HS. Heat stress enhanced the adrenal response to releasing factors. Additionally, the adrenal cortisol and FCI response to releasing factors was reduced during acute heat stress in cows fed OG. Collectively, these data suggest that OG supplementation reduced the adrenal responsiveness to factors regulating cortisol secretion during acute HS.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Bovinos/fisiologia , Hormônio Liberador da Corticotropina/farmacologia , Suplementos Nutricionais/análise , Leite/metabolismo , Vasopressinas/farmacologia , Animais , Dieta/veterinária , Feminino , Resposta ao Choque Térmico , Umidade , Hidrocortisona/sangue , Lactação , Paridade , Gravidez , Progesterona/sangue
17.
18.
J Dairy Sci ; 102(10): 9082-9096, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400890

RESUMO

The objectives of this study were to determine whether plane of nutrition (PON) of milk replacer previously provided to calves, and dosage level of Mannheimia haemolytica (MH), influenced inflammatory responses to a combined viral-bacterial respiratory challenge. Holstein calves (1 d of age; n = 30) were assigned to treatments in a 2 × 3 factorial with pre-weaning PON and MH dose as main effects (n = 5 per treatment). Calves were fed either a low (LPN; n = 15) or a high PON (HPN; n = 15) from birth through weaning. Calves fed LPN were fed 436 g of dry matter (DM) per day of milk replacer until weaning, and HPN calves were fed 797 g of DM per day of milk replacer from d 1 to 10 and 1,080 g of DM per day from d 11 until weaning. Calf starter and water were offered ad libitum. Calves were step-down weaned beginning at d 54 and moved into an enclosed barn at d 70. Indwelling rectal temperature (RT) recording devices and jugular catheters were inserted at d 80. Calves were challenged with 1.5 × 108 plaque-forming units (pfu) per mL of bovine herpesvirus-1 (BHV-1) in each nostril at d 81 and with either 106, 107, or 108 cfu of MH at d 84. Blood samples were collected at varying intervals relative to BHV-1 and MH challenges. Four LPN calves either died or were euthanized soon after the 144-h observation period, whereas all HPN calves survived the entire observation period. As dosage of MH administered increased, acute and systemic inflammatory responses increased. Higher doses of MH resulted in increased leukocyte, neutrophil, and haptoglobin concentrations in infected calves. Data from the current study suggest that the highest dose, 108 cfu, triggered weaned calves' acute disease response, whereas the lower doses, 106 and 107 cfu, caused more moderate inflammation and disease. The effects of PON on inflammation responses to the disease challenge indicated that calves previously fed the LPN diet had more severe pathophysiological responses. Calves fed LPN showed higher peripheral neutrophil and leukocyte counts and serum haptoglobin concentrations following the BHV-1 challenge. Additionally, following the MH challenge, LPN calves had higher peripheral neutrophil counts, neutrophil-to-lymphocyte ratios, and serum tumor necrosis factor-α concentrations. These data demonstrate that higher doses of MH increase the acute inflammatory response and prolong inflammation, and that calves previously fed LPN responded more severely to the combined viral-bacterial respiratory challenge.


Assuntos
Ração Animal , Dieta/veterinária , Herpesvirus Bovino 1 , Rinotraqueíte Infecciosa Bovina/prevenção & controle , Mannheimia haemolytica , Pneumonia Enzoótica dos Bezerros/prevenção & controle , Ração Animal/análise , Animais , Bovinos , Haptoglobinas , Inflamação/prevenção & controle , Inflamação/veterinária , Masculino , Leite , Substitutos do Leite/administração & dosagem , Neutrófilos , Desmame
19.
J Therm Biol ; 80: 37-44, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30784486

RESUMO

Temperature affects every organism on Earth and has been argued to be one of the most critical factors influencing organisms' ecology and evolution. Most organisms are susceptible to landscape temperature ranges that exceed their thermal tolerance. As a result, the distribution of landscape features that mitigate thermal extremes can affect movement and space use of organisms. Using Rio Grande wild turkey (Meleagris gallopavo intermedia) as a model species, we measured black bulb temperature throughout the diurnal period and identified vegetation characteristics at wild turkey locations and random landscape locations. We observed that the thermal landscape was highly heterogeneous with temperature varying up to 52 °C at a given ambient temperature. Vegetation type strongly influenced temperature across space during daily peak heating, with taller vegetation types (woody vegetation >2 m) having mean temperatures up to 8.95 °C cooler than the remainder of the landscape. However, these cooler vegetation types were uncommon, only accounting for 8.2% of the landscape. Despite the rarity of tall woody cover, wild turkey showed strong selection for this vegetation type particularly during peak daily heating with 74.9% of locations within 18 m of tree cover. Not only did wild turkey alter space use across time relative to temperature variation, but they also altered movement. We found that on the hottest days (≥35 °C), wild turkeys decreased movement by three fold during peak heating, while movement on cooler days (<30 °C) was uniform. Collectively, our data provide evidence that space use and movement for large avian species can be influenced by the thermal environment, and that the thermal environment is an important component of habitat for a species.


Assuntos
Regulação da Temperatura Corporal , Temperatura , Perus/fisiologia , Animais , Comportamento Animal , Feminino , Microclima , Movimento , Plantas
20.
Mol Psychiatry ; 22(8): 1126-1133, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27752081

RESUMO

Several neuropsychiatric and neurodegenerative disorders share stress as a risk factor and are more prevalent in women than in men. Corticotropin-releasing factor (CRF) orchestrates the stress response, and excessive CRF is thought to contribute to the pathophysiology of these diseases. We previously found that the CRF1 receptor (CRF1) is sex biased whereby coupling to its GTP-binding protein, Gs, is greater in females, whereas ß-arrestin-2 coupling is greater in males. This study used a phosphoproteomic approach in CRF-overexpressing (CRF-OE) mice to test the proof of principle that when CRF is in excess, sex-biased CRF1 coupling translates into divergent cell signaling that is expressed as different brain phosphoprotein profiles. Cortical phosphopeptides that distinguished female and male CRF-OE mice were overrepresented in unique pathways that were consistent with Gs-dependent signaling in females and ß-arrestin-2 signaling in males. Notably, phosphopeptides that were more abundant in female CRF-OE mice were overrepresented in an Alzheimer's disease (AD) pathway. Phosphoproteomic results were validated by demonstrating that CRF overexpression in females was associated with increased tau phosphorylation and, in a mouse model of AD pathology, phosphorylation of ß-secretase, the enzyme involved in the formation of amyloid ß. These females exhibited increased formation of amyloid ß plaques and cognitive impairments relative to males. Collectively, the findings are consistent with a mechanism whereby the excess CRF that characterizes stress-related diseases initiates distinct cellular processes in male and female brains, as a result of sex-biased CRF1 signaling. Promotion of AD-related signaling pathways through this mechanism may contribute to female vulnerability to AD.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Transtornos Cognitivos/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Fosforilação , Transporte Proteico/fisiologia , Fatores Sexuais , Transdução de Sinais/fisiologia , Estresse Psicológico/metabolismo , beta-Arrestina 2/metabolismo
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