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1.
Proc Natl Acad Sci U S A ; 121(5): e2307425121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38271339

RESUMO

We present evidence of a strong circular photon drag effect (PDE) in topological insulators (TIs) through the observation of helicity-dependent topological photocurrents with threefold rotational symmetry using THz spectroscopy in epitaxially-grown Bi2Se3 with reduced crystallographic twinning. We establish how twinned domains introduce competing nonlinear optical (NLO) responses inherent to the crystal structure that obscure geometry-sensitive optical processes through the introduction of a spurious mirror symmetry. Minimizing the twinning defect reveals strong NLO response currents whose magnitude and direction depend on the alignment of the excitation to the crystal axes and follow the threefold rotational symmetry of the crystal. Notably, photocurrents arising from helical light reverse direction for left/right circular polarizations and maintain a strong azimuthal dependence-a result uniquely attributable to the circular PDE, where the photon momentum acts as an applied in-plane field stationary in the laboratory frame. Our results demonstrate new levels of control over the magnitude and direction of photocurrents in TIs and that the study of single-domain films is crucial to reveal hidden phenomena that couple topological order and crystal symmetries.

2.
Can J Anaesth ; 70(8): 1362-1370, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37286748

RESUMO

PURPOSE: With uncertain prognostic utility of existing predictive scoring systems for COVID-19-related illness, the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) 4C Mortality Score was developed by the International Severe Acute Respiratory and Emerging Infection Consortium as a COVID-19 mortality prediction tool. We sought to externally validate this score among critically ill patients admitted to an intensive care unit (ICU) with COVID-19 and compare its discrimination characteristics to that of the Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores. METHODS: We enrolled all consecutive patients admitted with COVID-19-associated respiratory failure between 5 March 2020 and 5 March 2022 to our university-affiliated and intensivist-staffed ICU (Jewish General Hospital, Montreal, QC, Canada). After data abstraction, our primary outcome of in-hospital mortality was evaluated with an objective of determining the discriminative properties of the ISARIC 4C Mortality Score, using the area under the curve of a logistic regression model. RESULTS: A total of 429 patients were included, 102 (23.8%) of whom died in hospital. The receiver operator curve of the ISARIC 4C Mortality Score had an area under the curve of 0.762 (95% confidence interval [CI], 0.717 to 0.811), whereas those of the SOFA and APACHE II scores were 0.705 (95% CI, 0.648 to 0.761) and 0.722 (95% CI, 0.667 to 0.777), respectively. CONCLUSIONS: The ISARIC 4C Mortality Score is a tool that had a good predictive performance for in-hospital mortality in a cohort of patients with COVID-19 admitted to an ICU for respiratory failure. Our results suggest a good external validity of the 4C score when applied to a more severely ill population.


RéSUMé: OBJECTIF: Compte tenu de l'utilité pronostique incertaine des systèmes de notation prédictive existants pour les maladies liées à la COVID-19, le score de mortalité ISARIC 4C a été mis au point par l'International Severe Acute Respiratory and Emerging Infection Consortium en tant qu'outil de prédiction de la mortalité associée à la COVID-19. Nous avons cherché à valider en externe ce score chez les patient·es gravement malades atteint·es de COVID-19 admis·es dans une unité de soins intensifs (USI) et à comparer ses caractéristiques de discrimination à celles des scores APACHE II (Acute Physiology and Chronic Health Evaluation) et SOFA (Sequential Organ Failure Assessment). MéTHODE: Nous avons recruté toutes les personnes consécutives admises pour insuffisance respiratoire associée à la COVID-19 entre le 5 mars 2020 et le 5 mars 2022 dans notre unité de soins intensifs affiliée à l'université et dotée d'intensivistes (Hôpital général juif, Montréal, QC, Canada). Après l'abstraction des données, notre critère d'évaluation principal de mortalité à l'hôpital a été évalué dans le but de déterminer les propriétés discriminatives du score de mortalité ISARIC 4C, en utilisant la surface sous la courbe d'un modèle de régression logistique. RéSULTATS: Au total, 429 patient·es ont été inclus·es, dont 102 (23,8 %) sont décédé·es à l'hôpital. La fonction d'efficacité du récepteur (courbe ROC) du score de mortalité ISARIC 4C avait une surface sous la courbe de 0,762 (intervalle de confiance [IC] à 95 %, 0,717 à 0,811), tandis que celles des scores SOFA et APACHE II étaient de 0,705 (IC 95%, 0,648 à 0,761) et 0,722 (IC 95%, 0,667 à 0,777), respectivement. CONCLUSION: Le score de mortalité ISARIC 4C est un outil qui a affiché une bonne performance prédictive de la mortalité à l'hôpital dans une cohorte de patient·es atteint·es de COVID-19 admis·es dans une unité de soins intensifs pour insuffisance respiratoire. Nos résultats suggèrent une bonne validité externe du score 4C lorsqu'il est appliqué à une population plus gravement malade.


Assuntos
COVID-19 , Humanos , Estudos de Coortes , Mortalidade Hospitalar , Canadá/epidemiologia , Unidades de Terapia Intensiva , Estudos Retrospectivos , Prognóstico , Curva ROC
3.
J Dairy Sci ; 106(12): 9440-9450, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678763

RESUMO

Holsteins and Jerseys, the 2 most prominent dairy breeds in the United States, differ in many regards. They have not been evaluated for differences in oral behavior performance, despite anecdotal evidence that Jerseys perform more abnormal behaviors than Holsteins. As abnormal behaviors can indicate compromised welfare, we evaluated whether breed differences existed in year-old heifers. Because many oral behaviors could be expressed in abnormal ways, we also sought to describe performance of a wide range of behaviors and whether these varied among individuals. We studied 42 pair-housed heifers (33 Holstein, 9 Jersey) at 12.8 ± 1.1 mo of age (mean ± SD) that were restricted to 50% of their ad libitum total mixed ration (TMR) intake for 2 d as part of a short-term feed challenge. Using continuous video recording from 0800 to 2000 h on the second day of feed restriction, we scored time spent performing tongue rolling, tongue flicking, self-grooming, allogrooming, intersucking, drinking urine, drinking water, and nonnutritive oral manipulation (NNOM) of rice hull bedding, the feed bin, or other pen fixtures. Eating TMR was recorded at 5-min intervals. We found that Jerseys spent more time tongue rolling (3.3% vs. 0.2% proportion of 12-h observations) and performing all types of NNOM than Holsteins (feed bin: 3.8% vs. 2.4%; bedding: 7.7% vs. 5.4%; other: 7.5% vs. 4.2%; total: 19.0% vs. 12.0%), and tended to spend more time tongue flicking (1.4% vs. 1.1%). Jerseys spent less time allogrooming than Holsteins (1.3% vs. 3.4%). There was no evidence of an effect of breed on self-grooming (2.0%), water drinking (1.0%), eating TMR (16.0%), or intersucking (0.06%). Urine drinking was performed by 9 total heifers and was not compared between breeds. All behaviors were highly variable across individuals, particularly tongue rolling and intersucking. Allogrooming was more variable than self-grooming, and each subcategory of NNOM was more variable than total NNOM. Outliers, or extreme performance of oral behaviors relative to the rest of our population, were present in most behaviors. Heifers who were outliers in one behavior were not consistently outliers in all. Overall, there are breed differences in many oral behaviors in a feed-restricted environment. Despite no difference in proportion of time spent eating, Jerseys often performed higher levels of potentially abnormal behaviors than Holsteins, though both breeds performed many oral behaviors, sometimes at extreme levels, that may indicate a concern.


Assuntos
Ração Animal , Comportamento Alimentar , Humanos , Animais , Bovinos , Feminino , Ração Animal/análise , Abrigo para Animais , Asseio Animal , Dieta/veterinária
4.
J Dairy Sci ; 106(3): 1968-1985, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36653289

RESUMO

Many milk-fed dairy calves are not provided forage. In these settings, calves often perform abnormal repetitive behaviors (ARBs), including tongue rolling and nonnutritive oral manipulation (NNOM), which, based on their form, seem similar to movements used when processing feed. Feeding hay, typically presented as a short chop (≤5 cm) in a bucket, reduces ARBs. Our objective was to evaluate whether altering the presentation method of long hay (∼19 cm), by providing it in a bucket or a novel polyvinyl chloride (PVC) pipe feeder, could reduce ARBs. Holstein heifer calves were housed individually on sand and fed ad libitum starter grain and limited milk replacer (5.7-8.4 L/d step-up) via a bottle (Control, n = 9) or given access to mountaingrass hay in a bucket (Bucket, n = 9) or in a PVC pipe feeder (Pipe, n = 9). The 56 × 10.2 cm (length × diameter) PVC pipe feeder had 4 openings that were 6.35 cm wide, which required the calf to insert her tongue into the pipe and curl her tongue to extract hay. Treatments were applied from birth through 50 d of age, when step-down weaning began and TMR was provided to all calves. Calves were fully weaned at d 60. At wk 4 and 6, oral behaviors (eating, ruminating, drinking water, sucking milk, self-grooming, NNOM, tongue rolling, tongue flicking, and panting) were recorded by direct observation for 24 h using 1-0 sampling during 5-s intervals. Feeding long hay, regardless of presentation method, increased overall DMI, grain intake, and ADG compared with Control calves. Hay provision also increased rumination (25 vs. 15% of 24-h observations in Control) and eating time (5.5 vs. 2% in Control). Abnormal behaviors were seen in all calves. Hay provision reduced some of these, including NNOM (5 vs. 9% in Control). There was no difference in NNOM between calves fed hay in a pipe or bucket, even though Bucket calves consumed more hay (178 vs. 129 g/d in wk 6) and tended to spend more observations eating hay than Pipe calves (4.5 vs. 3%). Hay provision did not affect other behaviors: drinking water (0.5%), grooming (3%), or tongue flicking (3%). We also found evidence of other abnormal oral behaviors that have received less attention. Calves showed signs of polydipsia, and displayed excessive grooming, the latter indicated by overall duration, number of bouts per day, and duration of individual bouts (up to 25 min). Tongue rolling was expressed at low levels (up to 0.4% of intervals) but by 85% of calves. Feeding hay, both in a bucket and using novel methods, was not enough to counteract the welfare challenges associated with individual housing and limited ability to suck milk (<1% of time). Provision of long hay, regardless of presentation method, promotes rumination, improves performance (higher grain intake and ADG) and reduces at least some, but not all, of the considerable abnormal oral behaviors these calves performed.


Assuntos
Água Potável , Comportamento Alimentar , Animais , Bovinos , Feminino , Leite , Antagonistas de Receptores de Angiotensina , Dieta/veterinária , Ração Animal , Inibidores da Enzima Conversora de Angiotensina , Ingestão de Alimentos , Desmame , Peso Corporal
5.
J Dairy Sci ; 106(8): 5672-5686, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37331875

RESUMO

Dairy cattle are often raised in environments that lack natural feeding opportunities, and they perform abnormal repetitive behaviors (ARBs) as a result. Early life restriction can affect later life behavior. We evaluated whether access to hay in the milk-fed period would affect later life behavior in heifers experiencing short-term feed restriction and whether individuals were consistent in behavioral expression over time. We had 2 competing ideas about how this would unfold. First, being raised with hay, which reduced early life ARBs, could lead to fewer ARBs later in life. Alternatively, heifers that were raised without hay and performed more ARBs in early life might be more prepared for a later feed-restricted environment and thus engage in fewer ARBs than those raised with hay. We studied 24 pair-housed Holstein heifers. As calves, they were fed milk and grain from 0 to 7 wk of age (control) or given additional forage (hay). Tongue rolling, tongue flicking, nonnutritive oral manipulation (NNOM) of pen fixtures, self-grooming, and water drinking were recorded for 12 h (0800-2000 h) during wk 4 and 6 of life using 1-0 sampling at 5-s intervals. At the start of weaning at d 50, all calves were fed a total mixed ration. All calves were fully weaned at d 60 and socially housed by d 65 to 70. After this point, all individuals were raised the same way, according to farm protocol, in groups that included both treatments. At 12.4 ± 0.6 mo of age (mean ± standard deviation), heifers were restricted to 50% of their ad libitum total mixed ration intake for 2 d as part of a short-term feed challenge. Using continuous video recording from 0800 to 2000 h on d 2 of feed restriction, we scored time spent performing oral behaviors: the 5 previously scored while they were calves, along with intersucking, allogrooming, drinking urine, NNOM of rice hull bedding, and NNOM of feed bins. We found that early life access to hay did not affect behavior performed by heifers experiencing short-term feed restriction 1 yr later. Most heifers performed a wide variety of behaviors that appeared abnormal. All heifers performed tongue rolling and NNOM, and at higher levels than when they were calves, while tongue flicks and self-grooming were performed less by heifers. Individual performance of NNOM and tongue rolling were not related across age classes [correlation coefficient (r) = 0.17 and 0.11, respectively], but tongue flicks tended to be correlated (r = 0.37). Intersucking was recorded in 67% of heifers, despite their not being able to suckle a conspecific or dam in early life. Oral behaviors were highly variable across heifers, particularly tongue rolling and intersucking. Outliers, or extreme performance of oral behaviors relative to the rest of the population, were present for many behaviors. Most outliers were expressed by unique heifers that were not extreme in other behaviors. Overall, feeding individually housed, milk-limited calves hay for their first 7 wk did not affect later life performance of oral behaviors. The considerable variability, inconsistency across ages, and excessive performance of some behaviors raises additional questions about how these develop in cattle across life stages and about what we label "abnormal."


Assuntos
Antagonistas de Receptores de Angiotensina , Comportamento Alimentar , Animais , Bovinos , Feminino , Dieta/veterinária , Ração Animal/análise , Inibidores da Enzima Conversora de Angiotensina , Desmame
6.
J Dairy Sci ; 106(9): 6365-6374, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37500438

RESUMO

Hot-iron disbudding, the practice of cauterizing horn bud tissue to prevent horn growth in dairy calves, results in behavioral changes indicative of pain in the first few days after the procedure. However, few studies have quantified behavioral changes in the following weeks, while the burn wounds are still healing. Female Holstein calves were disbudded with a heated iron and pain relief (5.5 mL lidocaine cornual nerve block and 1 mg/kg oral meloxicam) at 4 to 10 d of age (n = 19) or not disbudded (n = 19). Calves wore ear tag accelerometers that reported the dominant behavior being performed at 1-min intervals from 3 to 21 d after disbudding. Compared with age-matched controls, disbudded calves tended to spend more time inactive throughout the observation period, ruminated less in the first 3 to 11 d after disbudding, and sucked more from a milk bottle beginning 5 d after disbudding until the end of the 21-d observation period. In addition to the accelerometer data, live observations of sleeping (using a behavioral proxy), lying, and ruminating were collected using instantaneous sampling at 5-min intervals for 24-h periods 3, 10, and 17 d after disbudding. Disbudded calves slept with their head down more on all live observation days and spent more time lying on the 17th d after disbudding, but ruminating did not differ compared with controls, in contrast to the accelerometer results. More time spent inactive, sleeping, and lying, and less time spent ruminating (as indicated by the accelerometer) can be interpreted as attempts to reduce painful stimulation of the disbudding wounds and allocate energy to healing. It is unclear whether the greater amount of sucking in the disbudded calves is nutritive (milk present) or non-nutritive (milk absent), as the algorithm did not distinguish the type of sucking, and further research is needed to explore the factors underlying this effect. We conclude that disbudding alters daily behavior patterns for at least 3 wk, far beyond the duration of recommended pain medication, raising additional welfare concerns about the procedure.


Assuntos
Cornos , Bovinos , Animais , Feminino , Cornos/cirurgia , Dor/veterinária , Lidocaína/uso terapêutico , Meloxicam , Ferro
7.
J Dairy Sci ; 106(12): 9494-9506, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678768

RESUMO

Limit feeding is a practice that is used to improve feed efficiency and control growth in dairy heifers, but also has negative consequences associated with hunger and restriction of feeding behavior. One such consequence could be intersucking (i.e., the licking or sucking of another animal's teats or udder). This behavior is reported to varying degrees in heifers, and thus, our first objective was to evaluate whether intersucking increased in response to short-term (48 h) feed restriction. Intersucking interventions, such as nose rings, are often applied to specific animals, and so our second objective was to describe intersucking performance in individual heifers, including those that represent outliers in this population. We studied 42 heifers (9 Jerseys, 33 Holsteins) aged 12.8 ± 1.1 mo (mean ± SD). They were housed in 21 pairs, the experimental unit for our first objective. We used a switchback design with 3 periods of 2 d each where heifers were fed ad libitum total mixed ration in the first and third periods (Baseline and Return, respectively), and limit fed to 50% of ad libitum intake in the second period (Restriction). We scored time spent intersucking continuously and eating at 5-min intervals from video recordings from 0800 to 2000 h on 4 d (baseline d 2, restriction d 2, return d 1, and return d 2). Heifer pairs spent less time eating (16 ± 0.4% mean percentage of 12-h observations ± SE), more time intersucking (27 ± 7 s/12 h), and engaged in longer bouts of intersucking (23 ± 5 s/bout) on Restriction d 2 compared with all other days (eating: 34.7 ± 1.1%, 44.2 ± 0.9%, 35.8 ± 1.1% of 12-h; intersucking time: 7 ± 2, 7 ± 3, 10 ± 5 s/12 h; intersucking bout length: 3 ± 1, 2 ± 1, 3 ± 1 s/bout; Baseline d 2, Return d 1, Return d 2, respectively). There was no difference in the number of bouts of intersucking across days (1.3 ± 0.2 bouts/12 h). The drop in eating during feed restriction was followed by a rebound on Return d 1 before returning to baseline levels. Time spent intersucking did not differ among ad libitum periods. Overall, 90% of the heifers performed intersucking on at least 1 of the 4 d, and did this for 1 to 127 s/12 h (range) in 1 to 13 bouts/12 h. Of the heifers that intersucked, 55% did this at extreme levels relative to the rest of the experimental population (outliers). Solid feed restriction exacerbated intersucking in year-old heifers, but this behavior was widespread.


Assuntos
Ração Animal , Ingestão de Alimentos , Animais , Bovinos , Feminino , Ração Animal/análise , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Comportamento Animal , Digestão , Dieta/veterinária
8.
J Dairy Sci ; 106(7): 5043-5053, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37268583

RESUMO

Application of ear tags in cattle is a common husbandry practice for identification purposes. Although it is known that ear tag application causes damage, little is known about the duration and process of wound healing associated with this procedure. Our objective was to develop a detailed scoring system and use it to quantify wound healing in dairy calves with plastic identification tags. Calves (n = 33) were ear tagged at 2 d of age, and wound photos were taken weekly until 9 to 22 wk of age. This approach generated 10 to 22 observations per calf that were analyzed using a novel wound scoring system. We developed this system to score the presence or absence of external tissue types related to piercing trauma or mechanical irritation along the top of the tag (impressions, crust, and desquamation) and around the piercing (exudate, crust, tissue growth, and desquamation). Ears were scored as "piercing only" when tissue around the ear tag was intact. We found that impressions, crust, tissue growth, and desquamation were still seen in many calves by 12 wk of age. This suggests that extrinsic factors, such as mechanical disturbance and irritation, may have contributed to prolonged wound healing. Indeed, impressions along the top of tag, likely caused by rubbing against the ear, were observed for nearly the full duration of the study. Further research is warranted to understand ways to improve the ear-tagging process.


Assuntos
Orelha , Cicatrização , Animais , Bovinos , Plásticos
9.
J Dairy Sci ; 105(5): 4434-4448, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35181131

RESUMO

Dairy calves often perform abnormal repetitive behaviors (ARBs) including tongue rolling and nonnutritive oral manipulation (NNOM) when opportunities to perform feeding behaviors are restricted. Many US dairy farms limit access to milk, a well-studied risk factor for ARBs. However, farms also commonly do not feed forage to young calves, and the motor patterns of oral ARBs resemble those necessary for acquiring and chewing solid feed. Our objective was to assess how access to hay from birth influenced time engaged in normal and abnormal oral behaviors across 24 h. Holstein heifer calves were housed individually on sand bedding and fed ad libitum water and grain (control, n = 11) or given additional access to hay (hay, n = 11) from birth. Calves were fed 5.7 to 8.4 L/d (step-up) of milk replacer via a teat. At the start of step-down weaning (50 ± 1 d), all calves were given access to a total mixed ration. Feed and water intake were measured daily. Oral behaviors (eating, ruminating, sucking milk, drinking water, panting, grooming, tongue flicking, tongue rolling, and NNOM) were recorded by direct observation at wk 2, 4, 6, and 8 using 1-0 sampling at 1-min intervals for 24 h. Grain, hay, and water intake increased over time in the preweaning period. One polydipsic calf regularly consumed >10 L of water/d. During weaning, hay calves tended to consume increasingly more total mixed ration, significantly more water, and less grain than control calves. Access to hay led to more observations spent eating solid feed (7% vs. 5%, mean percentage of intervals) and ruminating (24% vs. 16%) during the preweaning period compared with calves fed only grain, though control calves appeared to ruminate in absence of forage to re-chew. Rumination occurred, to a large extent, overnight. Hay calves also spent less time self-grooming (12% vs. 14%), tongue flicking (14% vs. 18%), and performing NNOM (17% vs. 21%) than control calves. Although NNOM peaked around milk feedings, all 3 behaviors were performed throughout the day. Tongue rolling was rare across treatments, as was panting, which occurred most frequently around 1400 h. There were no behavioral differences during weaning (wk 8). Overall, we found that hay provision affected most oral behaviors that calves perform; it promoted natural feeding behaviors and reduced abnormal ones, suggesting hay should be provided. We also found that calves performed other behaviors, including polydipsia, repetitive grooming, and apparent sham rumination, that may suggest a degree of abnormality in these behaviors that has not been previously identified. These results highlight the importance of considering all oral behaviors to better understand calf welfare.


Assuntos
Ração Animal , Dieta , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Ração Animal/análise , Animais , Peso Corporal , Bovinos , Dieta/veterinária , Ingestão de Alimentos , Grão Comestível , Feminino , Leite , Água , Desmame
10.
Opt Express ; 29(10): 14260-14268, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33985149

RESUMO

We demonstrate the all-optical manipulation of polymeric membranes in microfluidic environments. The membranes are decorated with handles for their use in holographic optical tweezers systems. Our results show that due to their form factor the membranes present a substantial increase in their mechanical stability, respect to micrometric dielectric particles. This intrinsic superior stability is expected to improve profoundly a wide range of bio-photonic applications that rely on the optical manipulation of micrometric objects.

11.
Phys Rev Lett ; 127(24): 241102, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34951783

RESUMO

High-quality optical resonant cavities require low optical loss, typically on the scale of parts per million. However, unintended micron-scale contaminants on the resonator mirrors that absorb the light circulating in the cavity can deform the surface thermoelastically and thus increase losses by scattering light out of the resonant mode. The point absorber effect is a limiting factor in some high-power cavity experiments, for example, the Advanced LIGO gravitational-wave detector. In this Letter, we present a general approach to the point absorber effect from first principles and simulate its contribution to the increased scattering. The achievable circulating power in current and future gravitational-wave detectors is calculated statistically given different point absorber configurations. Our formulation is further confirmed experimentally in comparison with the scattered power in the arm cavity of Advanced LIGO measured by in situ photodiodes. The understanding presented here provides an important tool in the global effort to design future gravitational-wave detectors that support high optical power and thus reduce quantum noise.

12.
J Dairy Sci ; 104(8): 9185-9194, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34053757

RESUMO

Oral behaviors, including feeding, drinking, grooming, and non-nutritive behaviors, are used as indicators of health and welfare in dairy calves, but continuous measurement of these behaviors can be labor intensive. Instantaneous sampling is often used to save labor but has only been validated for feeding behavior in calves. One-zero sampling may be an appropriate strategy well suited to capturing the rapid performance of non-nutritive behaviors. Our objective was to validate 1-0 and instantaneous sampling for measurement of oral behaviors around the time of bottle delivery against true values. Eleven Holstein heifer calves were housed individually, provided water, and fed a diet of starter grain and milk replacer (4.8-5.6 L/d step-up) via a bottle. When calves were 23 ± 7 d old, they were video recorded for 30 min before and after the morning 2.5 ± 0.2 L milk meal, from approximately 0900 to 1000 h. We measured ruminating, eating, drinking water, sucking milk, grooming, non-nutritive oral manipulation, and tongue flicks continuously and with instantaneous and 1-0 sampling at 5-, 10-, 30-, and 60-s intervals. We also examined the effect of instantaneous timing within these intervals. Estimates obtained through subsampling were compared with true values via regression analysis. The subsampling interval was determined to represent true values if the coefficient of determination ≥0.9, slope = 1, intercept = 0, and relative error <10%. Ruminating, drinking water, and eating were not performed by all 11 calves and were not included in the analysis. The proportions of time performing non-nutritive oral manipulation, grooming, and tongue flicks generated by continuous and 1-0 sampling were highly correlated but were consistently overestimated by 1-0 sampling, especially as calves spent more time engaged in these behaviors. Sucking milk was accurately represented at intervals of less than 30 s, likely due to most sucking bouts continuing for at least 150 s at a time and low between-calf variability compared with the other behaviors. Different start times within a given instantaneous interval resulted in wide variance in discrepancies between subsampling and continuous recording for all behaviors. We conclude that around milk feeding, 1-0 sampling is an appropriate choice to represent stimulus-elicited behavior, such as sucking milk in a milk-restricted system. However, time engaged in short, highly variable, or intermittent behaviors is not reliably captured via instantaneous or 1-0 sampling in the hour around bottle delivery.


Assuntos
Comportamento Alimentar , Leite , Ração Animal/análise , Animais , Bovinos , Dieta , Digestão , Ingestão de Alimentos , Feminino , Desmame
13.
Am J Transplant ; 20(10): 2899-2904, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32353210

RESUMO

The medical needs of the transgender population are increasingly recognized within the US health care system. Hormone therapy and gender-affirming surgery present distinct anatomic, hormonal, infectious, and psychosocial issues among transgender kidney transplant donors and recipients. We present the first reported experience with kidney transplantation and donation in transgender patients. A single-center case series (January 2014-December 2018) comprising 4 transgender kidney transplant recipients and 2 transgender living donors was constructed and analyzed. Experts in transplant surgery, transplant psychiatry, transplant infectious disease, pharmacy, and endocrinology were consulted to discuss aspects of care for these patients. Four transgender patients identified as male-to-female and 2 as female-to-male. Three of 6 had gender-affirming surgeries prior to transplant surgery, 1 of whom had further procedures posttransplant. Additionally, 4 patients were on hormone therapy. All 6 had psychiatric comorbidities. The 4 grafts have done well, with an average serum creatinine of 1.45 mg/dL at 2 years (range 1.01-1.85 mg/dL). However, patients encountered various postoperative complications, 1 of which was attributable to modified anatomy. Thus, transgender kidney transplant patients can present novel challenges in regard to surgical considerations as well as pre- and posttransplant care. Dedicated expertise is needed to optimize outcomes for this population.


Assuntos
Transplante de Rim , Pessoas Transgênero , Atenção à Saúde , Feminino , Humanos , Doadores Vivos , Masculino , Encaminhamento e Consulta
14.
Glob Chang Biol ; 26(5): 3091-3107, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32056344

RESUMO

Drought extent and severity have increased and are predicted to continue to increase in many parts of the world. Understanding tree vulnerability to drought at both individual and species levels is key to ongoing forest management and preparation for future transitions in community composition. The influence of subsurface hydrologic processes is particularly important in water-limited ecosystems, and is an under-studied aspect of tree drought vulnerability. With California's 2013-2016 extraordinary drought as a natural experiment, we studied four co-occurring woodland tree species, blue oak (Quercus douglasii), valley oak (Quercus lobata), gray pine (Pinus sabiniana), and California juniper (Juniperus californica), examining drought vulnerability as a function of climate, lithology and hydrology using regional aerial dieback surveys and site-scale field surveys. We found that in addition to climatic drought severity (i.e., rainfall), subsurface processes explained variation in drought vulnerability within and across species at both scales. Regionally for blue oak, severity of dieback was related to the bedrock lithology, with higher mortality on igneous and metamorphic substrates, and to regional reductions in groundwater. At the site scale, access to deep subsurface water, evidenced by stem water stable isotope composition, was related to canopy condition across all species. Along hillslope gradients, channel locations supported similar environments in terms of water stress across a wide climatic gradient, indicating that subsurface hydrology mediates species' experience of drought, and that areas associated with persistent access to subsurface hydrologic resources may provide important refugia at species' xeric range edges. Despite this persistent overall influence of the subsurface environment, individual species showed markedly different response patterns. We argue that hydrologic niche segregation can be a useful lens through which to interpret these differences in vulnerability to climatic drought and climate change.


Assuntos
Secas , Árvores , Ecossistema , Hidrologia , Tempo (Meteorologia)
15.
J Sex Med ; 17(5): 1025-1032, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32199854

RESUMO

BACKGROUND: The definitive treatment for erectile dysfunction is the surgical implantation of a penile prosthesis, of which the most common type is the 3-piece inflatable penile prosthesis (IPP) device. IPP surgery in outpatient freestanding ambulatory surgical centers (ASC) is becoming more prevalent as payers and health systems alike look to reduce healthcare costs. AIM: To evaluate IPP surgical outcomes in an ASC as compared to contemporaneously-performed hospital surgeries. METHODS: A database of all patients undergoing IPP implantation by practitioners in the largest private community urology group practice in the United States, from January 1, 2013 to August 1, 2019, was prospectively compiled and retrospectively reviewed. Cohorts of patients having IPP implantation performed in the hospital vs ASC setting were compared. MAIN OUTCOME MEASURE: The primary outcome measure was to compare surgical data (procedural and surgical times, need for hospital transfer from ASC) and outcomes (risk for device infection, erosion, and need for surgical revision) between ASC and hospital-based surgery groups. RESULTS: A total of 923 patients were included for this analysis, with 674 (73%) having ASC-based surgery and 249 (27%) hospital-based, by a total of 33 surgeons. Median procedural (99.5 vs 120 minutes, P < .001) and surgical (68 vs 75 minutes, P < .001) times were significantly shorter in the ASC. While the risk for device erosion and need for surgical revision were similar between groups, there was no higher risk for prosthetic infection when surgery was performed in the ASC (1.7% vs 4.4% [hospital], P = .02), corroborated by logistic regression analysis (odds ratio 0.39, P = .03). The risk for postoperative transfer of an ASC patient to the hospital was low (0.45%). The primary reason for mandated hospital-based surgery was medical (51.4%), though requirement as a result of insurance directive (39.7%) was substantial. CLINICAL IMPLICATIONS: IPP implantation in the ASC is safe, has similar outcomes compared to hospital-based surgery with a low risk for need for subsequent hospital transfer. STRENGTHS & LIMITATIONS: The strengths of this study include the large patient population in this analysis as well as the real-world nature of our practice. Limitations include the retrospective nature of the review as well as the potential for residual confounding. CONCLUSION: ASC-based IPP implantation is safe, with shorter surgical and procedural times compared to those cases performed in the hospital setting, with similar functional outcomes. These data suggest no added benefit to hospital-based surgery in terms of prosthetic infection risk. Weinberg AC, Siegelbaum MH, Lerner BD, et al. Inflatable Penile Prosthesis in the Ambulatory Surgical Setting: Outcomes From a Large Urological Group Practice. J Sex Med 2020;17:1025-1032.


Assuntos
Disfunção Erétil , Prática de Grupo , Implante Peniano , Prótese de Pênis , Disfunção Erétil/cirurgia , Humanos , Masculino , Estudos Retrospectivos
16.
Hum Brain Mapp ; 40(17): 5056-5068, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31403749

RESUMO

Investigations into the neural basis of reading have shed light on the cortical locus and the functional role of visual-orthographic processing. Yet, the fine-grained structure of neural representations subserving reading remains to be clarified. Here, we capitalize on the spatiotemporal structure of electroencephalography (EEG) data to examine if and how EEG patterns can serve to decode and reconstruct the internal representation of visually presented words in healthy adults. Our results show that word classification and image reconstruction were accurate well above chance, that their temporal profile exhibited an early onset, soon after 100 ms, and peaked around 170 ms. Further, reconstruction results were well explained by a combination of visual-orthographic word properties. Last, systematic individual differences were detected in orthographic representations across participants. Collectively, our results establish the feasibility of EEG-based word decoding and image reconstruction. More generally, they help to elucidate the specific features, dynamics, and neurocomputational principles underlying word recognition.


Assuntos
Encéfalo/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Leitura , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Adulto Jovem
17.
Phys Rev Lett ; 123(23): 231107, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868462

RESUMO

The Laser Interferometer Gravitational Wave Observatory (LIGO) has been directly detecting gravitational waves from compact binary mergers since 2015. We report on the first use of squeezed vacuum states in the direct measurement of gravitational waves with the Advanced LIGO H1 and L1 detectors. This achievement is the culmination of decades of research to implement squeezed states in gravitational-wave detectors. During the ongoing O3 observation run, squeezed states are improving the sensitivity of the LIGO interferometers to signals above 50 Hz by up to 3 dB, thereby increasing the expected detection rate by 40% (H1) and 50% (L1).

18.
Int J Toxicol ; 38(4): 251-264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31220972

RESUMO

There is overwhelming evidence that the microbiome must be considered when evaluating the toxicity of chemicals. Disruption of the normal microbial flora is a known effect of toxic exposure, and these disruptions may lead to human health effects. In addition, the biotransformation of numerous compounds has been shown to be dependent on microbial enzymes, with the potential for different host health outcomes resulting from variations in the microbiome. Evidence suggests that such metabolism of environmental chemicals by enzymes from the host's microbiota can affect the toxicity of that chemical to the host. Chemical-microbial interactions can be categorized into two classes: Microbiome Modulation of Toxicity (MMT) and Toxicant Modulation of the Microbiome (TMM). MMT refers to transformation of a chemical by microbial enzymes or metabolites to modify the chemical in a way that makes it more or less toxic. TMM is a change in the microbiota that results from a chemical exposure. These changes span a large magnitude of effects and may vary from microbial gene regulation, to inhibition of a specific enzyme, to the death of the microbes. Certain microbiomes or microbiota may become associated with different health outcomes, such as resistance or susceptibility to exposure to certain toxic chemicals, the ability to recover following a chemical-induced injury, the presence of disease-associated phenotypes, and the effectiveness of immune responses. Future work in toxicology will require an understanding of how the microbiome interacts with toxicants to fully elucidate how a compound will affect a diverse, real-world population.


Assuntos
Substâncias Perigosas/toxicidade , Microbiota/efeitos dos fármacos , Animais , Humanos
19.
Behav Res Methods ; 51(3): 1399-1425, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30203161

RESUMO

Most words are ambiguous, with interpretation dependent on context. Advancing theories of ambiguity resolution is important for any general theory of language processing, and for resolving inconsistencies in observed ambiguity effects across experimental tasks. Focusing on homonyms (words such as bank with unrelated meanings EDGE OF A RIVER vs. FINANCIAL INSTITUTION), the present work advances theories and methods for estimating the relative frequency of their meanings, a factor that shapes observed ambiguity effects. We develop a new method for estimating meaning frequency based on the meaning of a homonym evoked in lines of movie and television subtitles according to human raters. We also replicate and extend a measure of meaning frequency derived from the classification of free associates. We evaluate the internal consistency of these measures, compare them to published estimates based on explicit ratings of each meaning's frequency, and compare each set of norms in predicting performance in lexical and semantic decision mega-studies. All measures have high internal consistency and show agreement, but each is also associated with unique variance, which may be explained by integrating cognitive theories of memory with the demands of different experimental methodologies. To derive frequency estimates, we collected manual classifications of 533 homonyms over 50,000 lines of subtitles, and of 357 homonyms across over 5000 homonym-associate pairs. This database-publicly available at: www.blairarmstrong.net/homonymnorms/ -constitutes a novel resource for computational cognitive modeling and computational linguistics, and we offer suggestions around good practices for its use in training and testing models on labeled data.


Assuntos
Associação Livre , Adolescente , Feminino , Humanos , Linguística , Masculino , Filmes Cinematográficos , Semântica , Televisão , Adulto Jovem
20.
Am J Public Health ; 108(S4): S258-S265, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30383423

RESUMO

OBJECTIVES: To determine how sensitive estimates of lesbian, gay, bisexual, or questioning (LGBQ)-heterosexual youth health disparities are to the presence of potentially mischievous responders. METHODS: We used US data from the 2015 Youth Risk Behavior Survey, pooled across jurisdictions that included a question about sexual identity for a total sample of 148 960 students. We used boosted regressions (a machine-learning technique) to identify unusual patterns of responses to 7 screener items presumably unrelated to LGBQ identification, which generated an index of suspected mischievousness. We estimated LGBQ-heterosexual youth disparities on 20 health outcomes; then we removed 1% of suspected mischievous responders at a time and re-estimated disparities to assess the robustness of original estimates. RESULTS: Accounting for suspected mischievousness reduced estimates of the average LGBQ-heterosexual youth health disparity by up to 46% for boys and 23% for girls; however, screening did not affect all outcomes equally. Drug- and alcohol-related disparities were most affected, particularly among boys, but bullying and suicidal ideation were unaffected. CONCLUSIONS: Including screener items in public health data sets and performing rigorous sensitivity analyses can support the validity of youth health estimates.


Assuntos
Bissexualidade/estatística & dados numéricos , Interpretação Estatística de Dados , Homossexualidade/estatística & dados numéricos , Inquéritos e Questionários/estatística & dados numéricos , Inquéritos e Questionários/normas , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Assunção de Riscos , Adulto Jovem
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