bluuebunny/crossref_metadata_2025_split huggingface dataset:
A theoretical model for focal seizure initiation, propagation, termination, and progression
Authors: Liou Jyun-you , Smith Elliot H. , Bateman Lisa M. , Bruce Samuel L. , McKhann Guy M. , Goodman Robert R. , Emerson Ronald G. , Schevon Catherine A. , Abbott L. F. 
Published: August 2019

AbstractWe developed a neural network model that can account for the major elements common to human focal seizures. These include the tonic-clonic transition, slow advance of clinical semiology and corresponding seizure territory expansion, widespread EEG synchronization, and slowing of the ictal rhythm as the seizure approaches termination. These were reproduced by incorporating usage-dependent exhaustion of inhibition in an adaptive neural network that receives global feedback inhibition in addition to local recurrent projections. Our model proposes mechanisms that may underline common EEG seizure onset patterns and status epilepticus and postulates a role for synaptic plasticity in emergence of epileptic foci. Complex patterns of seizure activity and bi-stable seizure evolution end-points arise when stochastic noise is included. With the rapid advancement of clinical and experimental tools, we believe that this can provide a roadmap and potentially a testbed for future explorations of seizure mechanisms and clinical therapies.
Essential role of Bone morphogenetic protein 15 in porcine ovarian and follicular development and ovulation
Authors: Qin Yufeng , Tang Tao , Li Wei , Liu Zhiguo , Yang Xiaoliang , Shi Xuan , Sun Guanjie , Liu Xiaofeng , Wang Min , Liang Xinyu , Cong Peiqing , Mo Delin , Liu Xiaohong , Chen Yaosheng , He Zuyong 
Published: August 2019

ABSTRACTBone morphogenetic protein 15 (BMP15) is a multifunctional oocyte-specific secreted factor. It controls female fertility and follicular development in both species-specific and dosage-sensitive manners. Previous studies found that BMP15 played a critical role on follicular development and ovulation rate of mono-ovulatory mammalian species, but has minimal impact on poly-ovulatory mice. However, whether this is true in non-rodent poly-ovulatory species need to be validated. To investigate this question, we generated a BMP15 knockdown pig model. We found that BMP15 knockdown gilts showed markedly reduced fertility accompanied with phenotype of dysplastic ovaries containing significantly declined number of follicles, increased number of abnormal follicles, and abnormally enlarged antral follicles resulting in disordered ovulation. Molecular and transcriptome analysis revealed that knockdown of BMP15 significantly suppressed cell proliferation, differentiation, Fshr expression, leading to premature luteinization and reduced estradiol production in GCs, and simultaneously decreased the quality and meiotic maturation of oocyte. Our results provide in vivo evidences for the essential role of BMP15 in porcine ovarian and follicular development, and new insight into the complicated regulatory function of BMP15 in female fertility of poly-ovulatory species.
Locomotor suppression by a monosynaptic amygdala to brainstem circuit
Authors: Roseberry Thomas K. , Lalive Arnaud L. , Margolin Benjamin D. , Kreitzer Anatol C. 
Published: August 2019

AbstractThe control of locomotion is fundamental to vertebrate animal survival. Defensive situations require an animal to rapidly decide whether to run away or suppress locomotor activity to avoid detection. While much of the neural circuitry involved in defensive action selection has been elucidated, top-down modulation of brainstem locomotor circuitry remains unclear. Here we provide evidence for the existence and functionality of a monosynaptic connection from the central amygdala (CeA) to the mesencephalic locomotor region (MLR) that inhibits locomotion in unconditioned and conditioned defensive behavior in mice. We show that locomotion stimulated by airpuff coincides with increased activity of MLR glutamatergic neurons. Using retrograde tracing and ex vivo electrophysiology, we find that the CeA makes a monosynaptic connection with the MLR. In the open field, in vivo stimulation of this projection suppressed spontaneous locomotion, whereas inhibition of this projection had no effect. However, inhibiting CeA terminals within the MLR increased both neural activity and locomotor responses to airpuff. Finally, using a conditioned avoidance paradigm known to activate CeA neurons, we find that inhibition of the CeA projection increased successful escape, whereas activating the projection reduced escape. Together these results provide evidence for a new circuit substrate influencing locomotion and defensive behaviors.
Relating visual production and recognition of objects in human visual cortex
Authors: Fan Judith E. , Wammes Jeffrey D. , Gunn Jordan B. , Yamins Daniel L. K. , Norman Kenneth A. , Turk-Browne Nicholas B. 
Published: August 2019

AbstractDrawing is a powerful tool that can be used to convey rich perceptual information about objects in the world. What are the neural mechanisms that enable us to produce a recognizable drawing of an object, and how does this visual production experience influence how this object is represented in the brain? Here we evaluate the hypothesis that producing and recognizing an object recruit a shared neural representation, such that repeatedly drawing the object can enhance its perceptual discriminability in the brain. We scanned participants using fMRI across three phases of a training study: during training, participants repeatedly drew two objects in an alternating sequence on an MR-compatible tablet; before and after training, they viewed these and two other control objects, allowing us to measure the neural representation of each object in visual cortex. We found that: (1) stimulus-evoked representations of objects in visual cortex are recruited during visually cued production of drawings of these objects, even throughout the period when the object cue is no longer present; (2) the object currently being drawn is prioritized in visual cortex during drawing production, while other repeatedly drawn objects are suppressed; and (3) patterns of connectivity between regions in occipital and parietal cortex supported enhanced decoding of the currently drawn object across the training phase, suggesting a potential substrate for learning how to transform perceptual representations into representational actions. Taken together, our study provides novel insight into the functional relationship between visual production and recognition in the brain.Significance StatementHumans can produce simple line drawings that capture rich information about their perceptual experiences. However, the mechanisms that support this behavior are not well understood. Here we investigate how regions in visual cortex participate in the recognition of an object and the production of a drawing of it. We find that these regions carry diagnostic information about an object in a similar format both during recognition and production, and that practice drawing an object enhances transmission of information about it to downstream regions. Taken together, our study provides novel insight into the functional relationship between visual production and recognition in the brain.
Chance and Necessity in the Pleiotropic Consequences of Adaptation for Budding Yeast
Authors: Jerison Elizabeth R. , Nguyen Ba Alex N. , Desai Michael M. , Kryazhimskiy Sergey 
Published: August 2019

AbstractMutations that a population accumulates during evolution in one (“home”) environment may cause fitness gains or losses in other conditions. Such pleiotropic fitness effects determine the evolutionary fate of the population in variable environments and can lead to ecological specialization. It is unclear how the pleiotropic outcomes of evolution are shaped by the intrinsic randomness of the evolutionary process and by the deterministic variation in selection pressures across environments. To address this question, we evolved 20 replicate populations of the yeastSaccharomyces cerevisiaein 11 laboratory environments and measured their fitness across multiple other conditions. We found that evolution in all home environments led to a diversity of patterns of pleiotropic fitness gains and losses, driven by multiple types of mutations. Approximately 60% percent of this variation are explained by clone’s home environment and the most common parallel genetic changes, while about 40% are attributed to the stochastic accumulation of mutations whose pleiotropic effects are unpredictable. On average, populations specialized to their home environment, but generalists also evolved in almost all conditions. Our results suggest that the mutations accumulating in a home environment incur a variety of pleiotropic effects, from costs to benefits, with different probabilities. Therefore, whether a population evolves towards a specialist or a generalist phenotype is heavily influenced by chance.
Hummingbirds budget energy flexibly in response to changing resources
Authors: Shankar Anusha , Graham Catherine H. , Canepa Joseph R. , Wethington Susan M. , Powers Donald R. 
Published: August 2019

Abstract

A key component of individual fitness is the ability to manage energy stores in response to variable resource availability, but because directly measuring energy budgets is difficult, daily energy management is rarely measured.

Hummingbirds' energy management is relatively simple to model compared to other endotherms because they have high mass‐specific metabolic rates and store little fat.

We determined which aspects of the hummingbird daily energy budget (i.e. thermoregulation, daytime activity costs, night‐time costs) change at the individual level in response to environmental variation.

We found that daily energy expenditure varied threefold in two populations of broad‐billed hummingbirds (Cynanthus latirostris).

Our model indicated the energy budget was distributed in the following proportions: daytime activity, 59% (range 22%–84%); thermoregulation, 23% (11%–32%); basal metabolism, 7% (3%–16%); and night‐time energy, 17% (6%–37%). Activity costs were higher at the hotter, homogeneous site and during the early‐wet season at both sites.

Increased daily energy expenditure was related to decreased nectar availability and not significantly related to temperature or bird mass. With climate change, the indirect energetic costs of shifting resources could have greater impacts on endotherm energy budgets than direct costs such as thermoregulation. Increased foraging and activity costs could decrease the energy available to birds for somatic repair and reproduction, potentially causing differential fitness across seasons and sites.

A free Plain Language Summary can be found within the Supporting Information of this article.
Linking epigenetics and biological conservation: Towards a conservation epigenetics perspective
Authors: Rey Olivier , Eizaguirre Christophe , Angers Bernard , Baltazar‐Soares Miguel , Sagonas Kostas , Prunier Jérôme G. , Blanchet Simon 
Published: August 2019

Abstract

Biodiversity conservation is a global issue where the challenge is to integrate all levels of biodiversity to ensure the long‐term evolutionary potential and resilience of biological systems. Genetic approaches have largely contributed to conservation biology by defining “conservation entities” accounting for their evolutionary history and adaptive potential, the so‐called evolutionary significant units (ESUs). Yet, these approaches only loosely integrate the short‐term ecological history of organisms.

Here, we argue that epigenetic variation, and more particularly DNA methylation, represents a molecular component of biodiversity that directly links the genome to the environment. As such, it provides the required information on the ecological background of organisms for an integrative field of conservation biology.

We synthesize knowledge about the importance of epigenetic mechanisms in (a) orchestrating fundamental development alternatives in organisms, (b) enabling individuals to respond in real‐time to selection pressures and (c) improving ecosystem stability and functioning.

Using practical examples in conservation biology, we illustrate the relevance of DNA methylation (a) as biomarkers of past and present environmental stress events as well as biomarkers of physiological conditions of individuals; (b) for documenting the ecological structuring/clustering of wild populations and hence for better integrating ecology into ESUs; (c) for improving conservation translocations; and (d) for studying landscape functional connectivity.

We conclude that an epigenetic conservation perspective will provide environmental managers the possibility to refine ESUs, to set conservation plans taking into account the capacity of organisms to rapidly cope with environmental changes, and hence to improve the conservation of wild populations.

A free Plain Language Summary can be found within the Supporting Information of this article.
Alternative functional trajectories along succession after different land uses in central Amazonia
Authors: Fernandes Neto Jose G. , Costa Flavia R. C. , Williamson G. Bruce , Mesquita Rita C. G. 
Published: August 2019

Abstract

The recovery capacity and the successional pathways of tropical forests after anthropogenic disturbance vary considerably and may depend on prior land‐use type and intensity. It is still unclear if forests subjected to high intensity impact, such as periodically burned pastures, are capable of restoring their original functional properties.

This study analysed the functional trait dynamics of the dominant species in successional trajectories following two land uses, pasture or clear‐cut, north of Manaus. Fourteen years of demographic data from the Biological Dynamics of Forest Fragments Project were used to determine the dominant species of the two successional trajectories, for which leaf area, leaf dry mass content, specific leaf area and wood density were collected, whereas seed mass was obtained from literature. Community weighted mean of each trait was weighted by basal area determined annually along succession. Prinicpal components analysis was used to analyse the extension and direction of the functional trajectories of plots.

Forests regenerating from pastures increased in wood density through successional time, but other traits did not change significantly. Succession after clear‐cut exhibited increasing leaf dry mass content and seed mass, and decreasing leaf area over time, but no change in wood density. Functional trajectories of plots after clear‐cut were more extensive and directional than those of pasture‐derived plots.

Synthesis and applications. We demonstrate how central Amazonian secondary forests subjected to different land uses show differences in functional trait trajectories, in ways parallel to previously shown changes in biomass, floristic diversity and forest structure. These results indicate that natural recovery of forest functional traits is affected by prior land‐use history, with implications for management and restoration. Thus, natural recovery of forests on abandoned pastures is much slower than clear‐cuts, even though seed sources from mature forests are very close to these areas, and the former may need intervention to counteract the diverted succession.
Deep microbial analysis of multiple placentas shows no evidence for a placental microbiome
Authors: Kuperman AA , Zimmerman A , Hamadia S , Ziv O , Gurevich V , Fichtman B , Gavert N , Straussman R , Rechnitzer H , Barzilay M , Shvalb S , Bornstein J , Ben‐Shachar I , Yagel S , Haviv I , Koren O 
Published: August 2019

ObjectivesTo resolve the controversy regarding the presence of a microbiota in the placenta.DesignClassical and molecular microbiological study.SettingAll samples were collected during caesarean section.PopulationA total of 28 human placentas and six murine placentas.MethodsAll 28 human placentas were checked for 16S rRNA gene amplification products. Three locations from four selected human placentas and three ‘environmental controls’ for each placenta were placed in seven culture media. The four selected human placentas were further analysed using Gram stain, immunohistochemistry for bacteria, electron microscopy, and TaqMan RT‐qPCR. Six placentas from three SPF mice were cut into four pieces each, and further analysed for 16S rRNA gene amplification.Main outcome measuresMicrobiological and molecular evidence of bacteria.ResultsNone of the placental cultures used for the full analysis, or their environmental cultures, was positive for bacterial growth. None of the other methods showed any evidence of bacteria. Immunohistochemistry showed negligible bacterial counts. None of the murine placentas showed evidence of 16S rRNA gene amplification.ConclusionsOur results support that the fetal environment in the womb is sterile. Based on the immunohistochemistry and the limit of detection of the other methods used, if a placental microbiome exists, it is of extreme low biomass, and thus its effect on clinical phenotypes is probably minor, if it exists at all.Tweetable abstractUsing several microbiological and molecular methods in parallel, we found no compelling evidence of bacteria in human and mouse placentas.
Body mass index, abdominal fatness, weight gain and the risk of urinary incontinence: a systematic review and dose–response meta‐analysis of prospective studies
Authors: Aune D , Mahamat‐Saleh Y , Norat T , Riboli E 
Published: August 2019

BackgroundAdiposity has been associated with elevated risk of urinary incontinence in epidemiological studies; however, the strength of the association has differed between studies.ObjectivesTo conduct a systematic literature review and dose–response meta‐analysis of prospective studies on adiposity and risk of urinary incontinence.Search strategyWe searched PubMed and Embase databases up to 19 July 2017.Selection criteriaProspective cohort studies were included.Data collection and analysisData were extracted by one reviewer and checked for accuracy by a second reviewer. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random effects models.Main resultsTwenty‐four prospective studies were included. The summary RR per 5 kg/m2 increment in body mass index (BMI) was 1.20 (95% CI 1.16–1.25, I2 = 62%, n = 11) for population‐based studies and 1.19 (95% CI 1.08–1.30, I2 = 87.1%, n = 8) for pregnancy‐based studies, 1.18 (95% CI 1.14–1.22, I2 = 0%, n = 2) per 10 cm increase in waist circumference and 1.34 (95% CI 1.11–1.62, I2 = 90%, n = 2) per 10 kg of weight gain. Although the test for nonlinearity was significant for BMI, P = 0.04, the association was approximately linear. For subtypes of urinary incontinence the summary RR per 5 BMI units was 1.45 (95% CI 1.25–1.68, I2 = 85%, n = 3) for frequent incontinence, 1.52 (95% CI 1.37–1.68, I2 = 34%, n = 4) for severe incontinence, 1.33 (95% CI 1.26–1.41, I2 = 0%, n = 8) for stress incontinence, 1.26 (95% CI 1.14–1.40, I2 = 70%, n = 7) for urge incontinence, and 1.52 (95% CI 1.36–1.69, I2 = 0%, n = 3) for mixed incontinence.ConclusionThese results suggest excess weight may increase risk of urinary incontinence.Tweetable abstractOverweight and obesity increase the risk of urinary incontinence.
Radiation Oncology Quality Assessment Tool: A proposal for a new audit tool in modern radiation oncology
Authors: Atwell Daisy B , Booth Clemency , Vignarajah Dinesh D , Knesl Marcel , Buddle Nicole , Hoozer Marshall , Min Myo 
Published: August 2019

AbstractIntroductionAs a consequence of the development of improved treatment techniques and utilisation of digital records in radiation oncology, the RANZCR Peer Review Audit Tool has become outdated. The aim of this internal audit was to objectively evaluate the practice of our radiation oncology department to ensure that patients are being treated according to evidence‐based national guidelines through the use of a new self‐audit algorithm, the Radiation Oncology Quality Assessment Tool (ROQAT).MethodsUsing ROQAT, a retrospective audit was conducted of patients who received definitive treatment within the first six months (June 2017–November 2017) of opening a new radiation oncology department at the Sunshine Coast University Hospital. Data were collected from MOSAIQ® and electronic medical records.ResultsTwo hundred and six patients were included. The median age was 65 years. Most commonly treated tumour streams included: breast (n = 62), skin (n = 31), colorectal (n = 25), genitourinary (n = 21) and head and neck (n = 21). Documentation was complete for all patients. Seventy‐four per cent of patients were discussed in a multidisciplinary team meeting. Fifty‐five per cent of patients were treated with inverse planning techniques. Treatment with radiation therapy was indicated in 97% of patients. Dose and fractionation were concordant with protocols in 83% of cases. Thirty‐nine per cent received concurrent chemotherapy, and of these, 93% were in accordance with protocols. More than 50% were treated according to published delineation protocols.ConclusionThe ROQAT is a proposal for a new audit tool that reflects modern radiation therapy practice, with emphasis on compliance with evidence‐based guidelines.
Measuring Real Activity Management
Authors: Cohen Daniel , Pandit Shailendra , Wasley Charles E. , Zach Tzachi 
Published: August 2019

ABSTRACTTo test hypotheses about earnings management, many studies investigate managers' manipulation of real activities (real earnings management, REM). Tests using measures of abnormal REM hinge critically on the measurement of normal real activities. Yet, there is no systematic evidence on the statistical properties of commonly used REM measures. We provide such evidence by documenting the Type I error rates and power of the test of the REM measures commonly used in the literature. We find these measures are often misspecified with Type I error rates that deviate from the nominal significance level of the test, especially in samples of firms with extreme performance or firm characteristics. We also compare the specification and power of traditional REM measures with performance‐matched REM measures to see if the latter provide better specified and more powerful tests. While performance‐matched REM measures are not immune from misspecification in all settings, in general they are better specified under the null hypothesis (i.e., in terms of Type I errors) than are traditional REM measures. Comparisons of the power to detect abnormal REM reveal that neither approach, traditional or performance‐matched, is consistently more powerful than the other in terms of detecting abnormal REM ranging from 1 to 10 percent of (lagged) total assets. The absence of a dominant approach to measure abnormal REM leads us to recommend that future researchers report results using both traditional and performance‐matched measures, so that readers are able to clearly assess the reliability of the inferences drawn about the magnitude and significance of the abnormal REM documented in a given study.
Short Sellers and Long‐Run Management Forecasts
Authors: Chen Xia , Cheng Qiang , Luo Ting , Yue Heng 
Published: August 2019

ABSTRACTWe examine how short sellers affect long‐run management forecasts using a natural experiment (Regulation SHO) that relaxes short‐selling constraints on a group of randomly selected firms (referred to as pilot firms). We find that compared to other firms, the pilot firms issue more long‐run good news forecasts but do not change the frequency of long‐run bad news forecasts. The increase in good news forecasts is greater when the pilot firms have higher‐quality forecasts, greater uncertainty about firm value, or higher manager equity incentives. Overall, these results and the results of additional analyses indicate that the reduction in short‐selling constraints and the increase in short‐selling threat induce managers to enhance disclosures through more long‐run good news forecasts to discourage short sellers.