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The use of anabolic androgenic steroids (AAS), such as testosterone, is associated with a myriad of physiological and behavioral health concerns. Most notably, in both humans and rats, exposure to supraphysiological levels of testosterone has been shown to increase aggressive-like behaviors. However, it is unclear if testosterone enhances the motivation to engage in aggressive-type behaviors to begin with. To elucidate the effects of testosterone on the motivation to seek out a potentially aggressive encounter, rats were tested on a social motivation task in which physical contact between test and stimulus rats was prevented by a wire barrier, which eliminated the possibility of physical provocation. Relative to vehicle treated rats, rats treated with testosterone during adolescence exhibited lower levels of social motivation, as indicted by a reduction in the amount of time spent adjacent to the wire barrier. Over the course of the social motivation test, there were no differences between testosterone and vehicle treated rats in the frequency of rearing behavior and the total number of fecal boli, which suggests that the testosterone-induced reduction in social motivation occurred independent of changes in activity and emotionality, respectively. Consistent with previous studies, testosterone treatment during adolescence decreased total weight gain, increased the weights of the bulbourethral glands, and decreased the weights of the testes. These results suggest that the heightened levels of aggression following testosterone exposure that have been reported in other studies are likely not due to a greater motivation to seek out an interaction with a conspecific of the same sex. Abbreviations: ASS – Anabolic Androgenic Steroids; PND – Post Natal Day; HPA axis – Hypothalamic-Pituitary-Adrenal axis; HPG axis – Hypothalamic-Pituitary-Gonad axis

Although many species shift their phenology with climate change, species vary significantly in the direction and magnitude of these responses (i.e., phenological sensitivity). Studies increasingly detect early phenology or high phenological sensitivity to climate in non-native species, which may favor non-native species over natives in warming climates. Yet relatively few studies explicitly compare phenological responses to climate between native vs. non-native species or between non-native populations in the native vs. introduced range, limiting our ability to quantify the role of phenology in invasion success. Here, we review the empirical evidence for and against differences in phenology and phenological sensitivity to climate in both native vs. non-native species and native and introduced populations of non-native species. Contrary to common assumptions, native and non-native plant species did not consistently differ in mean phenology or phenological sensitivity. However, non-native plant species were often either just as or more sensitive, but rarely less sensitive, to climate as natives. Introduced populations of non-native plant species often show earlier reproduction than native populations of the same species, but there was mixed evidence for differences in phenological sensitivity between introduced and native plant populations. We found very few studies comparing native vs. invasive animal phenology. Future work should characterize phenological sensitivity to climate in native vs. non-native plant and animal species, in native vs. introduced populations of non-native species, and across different stages of invasion, and should carefully consider how differences in phenology might promote invasion success or disadvantage native species under climate change.

Abstract Sex ratios affect population dynamics and individual fitness, and changing sex ratios can be indicative of shifts in sex‐specific survival at different life stages. While climate and landscape changes alter sex ratios of wild bird populations, long‐term, landscape scale assessments of sex ratios are rare. Further, little work has been done to understand changes in sex ratios in avian communities. In this manuscript, we analyze long‐term (1961–2015) data on five species of ducks across five broad climatic regions of the United States to estimate the effects of drought and long‐term trends on the proportion of juvenile females captured at banding. As waterfowl have a 1:1 sex ratio at hatch, we interpret changes in sex ratios of captured juveniles as changes in sex‐specific survival rates during early life. Seven of 12 species‐region pairs exhibited evidence for long‐term trends in the proportion of juvenile females at banding. The proportion of juvenile females at banding increased for duck populations in the western United States and typically declined for duck populations in the eastern United States. We only observed evidence for an effect of drought in two of the 12 species‐region pairs, where the proportion of females declined during drought. As changes to North American landscapes and climate continue and intensify, we expect continued changes in sex‐specific juvenile survival rates. More broadly, we encourage further research examining the mechanisms underlying long‐term trends in juvenile sex ratios in avian communities.

This work presents a methodology for using machine learning (ML) techniques in combination with 3D computational fluid dynamics (CFD) modeling to optimize the cold-start fast-idle phase of a gasoline direct injection spark ignition (DISI) engine. The optimization process implies the identification of the range of operating parameters, that will ensure the following criteria under cold-start conditions: (1) a fixed IMEP of 2 bar (BMEP of 0 bar), (2) a stoichiometric exhaust equivalence ratio (based on carbon-to-oxygen atoms) to ensure the efficient operation of the after-treatment system, (3) enough exhaust heat flux to ensure a rapid light-off of the after-treatment system, and (4) reduced NOx and HC emissions. A total of six operating parameters will be identified as having a significant influence on cold-start engine performance. These parameters are associated with the fuel injection strategy (end of the second injection, injection pressure, and fuel mass); combustion strategy (spark timing, spark energy); and intake airflow (intake manifold pressure). Performing an optimization study exclusively using multi-cycle (at least 3 cycles) 3D CFD simulations would be an arduous task. For example, to achieve an exhaust equivalence ratio of 1 and an IMEP of 2 bar, multiple iterations would be required for fuel mass (to account for film formation), intake manifold pressure (to ensure enough air in-cylinder), and spark timing (to ensure the fixed load). This process would be more convoluted and expensive with the addition of constraints for exhaust heat flux and emissions. A promising approach to tackling such a complicated optimization process is to employ the concept of machine learning, which demands a database formed by the six operating parameters mentioned above. The current work will demonstrate a strategy of combining CFD modeling with advanced Gaussian Process Regression (GPR)-based ML models to make predictions about DISI cold-start behavior with acceptable accuracy and a substantially reduced computational time.

Low temperature combustion strategies have demonstrated high thermal efficiency with low pollutant emissions (e. g., oxides of nitrogen and particulate matter), resulting from reduced heat transfer losses and lean air-fuel mixtures. One such advanced compression ignition combustion strategy, Reactivity Controlled Compression Ignition (RCCI), has demonstrated improved control over the heat release event due to the introduction of in-cylinder stratification of equivalence ratio and chemical reactivity via direct injection of a high-reactivity fuel into a premixed low-reactivity fuel/air mixture. The nature of the RCCI strategy provides inherent fuel flexibility, however, the direct injection strategy must be tailored to the combination of premixed and direct injected fuel chemistry and engine operating conditions to optimize efficiency and emissions. In this work, a 0-D methodology for predicting the required fuel stratification for a desired heat release rate profile for kinetically controlled stratified-charge combustion strategies is proposed. The methodology, referred to as Fuel Stratification Analysis (FSA), was inspired by a similar approach which utilized ignition predictions calculated via a Livengood-Wu integral approach correlated with experimental heat release profiles to determine in-cylinder temperature stratification in homogeneous charge compression ignition (HCCI) combustion. The methodology proposed in this work expands upon this method to include strategies involving fuel stratification (such as RCCI). Reacting and non-reacting CFD simulations were performed with the KIVA3V release 2 code to validate the CFD. Reacting simulations were validated against published experimental HCCI and RCCI data, and non-reacting simulations were used to generate fuel distribution profiles to compare to the FSA results. The results of this validation showed that the FSA method was able to provide good overall agreement in the predicted fuel distribution compared to the actual fuel distributions from CFD simulations within the range of injection timings of interest in RCCI combustion (−140° to about −35° after top-dead-center). For later injection timings, FSA predictions are not able to capture the actual fuel distributions present at the start of combustion, likely due to a transition into a mixing dominated, as opposed to a kinetically dominated, combustion regime, thereby violating one or more inherent method assumptions.

BackgroundBasal ganglia hemorrhage (BG-ICH) and thalamic hemorrhage (TH-ICH) have been historically grouped into a single “deep” hemorrhage group in prior studies. We aimed to assess whether BG-ICH and TH-ICH have different optimal hematoma volume cut points in predicting functional outcome.MethodsPatients with BG-ICH and TH-ICH with no preexisting disabilities who were enrolled in a single-center intracerebral hemorrhage (ICH) cohort study were studied. The hematoma volume of patients who achieved modified Rankin Scale (mRS) of ≤2 and ≤3 at 3 months were compared between BG-ICH and TH-ICH groups. Receiver operating characteristic (ROC) curves were created to determine the optimal hematoma volume cut points in predicting 3-month mRS of ≤2 and ≤3 for BG-ICH and TH-ICH groups.ResultsA total of 135 (81 BG-ICH and 54 TH-ICH) patients were studied. The hematoma volume among those with 3-month mRS ≤ 2 (BG-ICH: 9.5 ± 5.4 cm3 vs. TH-ICH: 5.1 ± 4.9 cm3, p = 0.01) and 3-month mRS ≤ 3 (BG-ICH: 14.2 ± 13.4 cm3 vs. TH-ICH: 4.7 ± 4.1 cm3, p = 0.001) were smaller in TH-ICH than BG-ICH. The area under the ROC curve in predicting mRS ≤ 2 was 0.838 for BG-ICH (optimal hematoma volume cut point: 18.0 cm3, sensitivity 72.1%, specificity 95.0%) and 0.802 for TH-ICH (optimal hematoma volume cut point: 4.6 cm3, sensitivity 83.8%, specificity 70.6%); and in predicting mRS ≤ 3 was 0.826 for BG-ICH (optimal hematoma volume cut point: 28.8 cm3, sensitivity 71.4%, specificity 93.8%) and 0.902 for TH-ICH (optimal hematoma volume cut point: 5.5 cm3, sensitivity 92.9%, specificity 76.9%).ConclusionTH-ICH have smaller optimal hematoma volume cut points than BG-ICH in predicting functional outcome.

BackgroundDisparities in outcome after intracerebral hemorrhage (ICH) among Asians, Native Hawaiians, and other Pacific Islanders (NHOPI) have been inadequately studied. We sought to assess differences in functional outcome between Asians and NHOPI after ICH.MethodsA multiracial prospective cohort study of ICH patients was conducted from 2011 to 2016 at a tertiary center in Honolulu, HI, USA to assess racial disparities in outcome after ICH. Favorable outcome was defined as 3-month modified Rankin Scale (mRS) score ≤2. Patients with no available 3-month functional outcome, race other than Asians and NHOPI, and baseline mRS > 0 were excluded. Multivariable analyses using logistic regression were performed to assess the impact of race on favorable outcome after adjusting for the ICH Score, early do-not-resuscitate (DNR) order and dementia/cognitive impairment.ResultsA total of 220 patients (161 Asians, 59 NHOPI) were studied. Overall, 65 (29.5%) achieved favorable outcome at 3 months. NHOPI were younger than Asians (p

Developmental initiation of plant vascular tissue, including xylem and phloem, from the vascular cambium depends on environmental factors, such as temperature and precipitation. Proper formation of vascular tissue is critical for the transpiration stream, along with photosynthesis as a whole. While effects of individual environmental factors on the transpiration stream are well studied, interactive effects of multiple stress factors are underrepresented. As expected, climate change will result in plants experiencing multiple co-occurring environmental stress factors, which require further studies. Also, the effects of the main climate change components (carbon dioxide, temperature, and drought) on vascular cambium are not well understood. This review aims at synthesizing current knowledge regarding the effects of the main climate change components on the initiation and differentiation of vascular cambium, the transpiration stream, and photosynthesis. We predict that combined environmental factors will result in increased diameter and density of xylem vessels or tracheids in the absence of water stress. However, drought may decrease the density of xylem vessels or tracheids. All interactive combinations are expected to increase vascular cell wall thickness, and therefore increase carbon allocation to these tissues. A comprehensive study of the effects of multiple environmental factors on plant vascular tissue and water regulation should help us understand plant responses to climate change.

On présente ici les principaux résultats de l'étude géochimique réalisée, dans le bassin de Paris, à partir des déblais et des carottes provenant de 100 sondages pétroliers ou miniers, et des huiles prélevées dans les réservoirs du Mésozoïque (Trias, Bathonien supérieur, Néocomien). Les différentes méthodes géochimiques utilisées sont la pyrolyse, particulièrement bien adaptée à l'étude des nombreux échantillons de déblais recueillis, la chromatographie en phase gazeuse pour l'analyse détaillée des huiles et des extraits de roche, la spectrométrie de masse pour l'étude des biomarqueurs. Les époques principales de formation de l'huile et du gaz ont été déterminées par simulation sur ordinateur d'un modèle mathématique de genèse des hydrocarbures. Les méthodes de pyrolyse ont permis de dresser des logs géochimiques des forages étudiés et de déterminer, par le calcul, les paramètres de pyrolyse initiaux des roches-mères, avant leur enfouissement. On a pu ainsi établir, dans le périmètre étudié, des cartes de carbone organique initial, de potentiels pétroliers totaux et de quantités d'HC migrés. L'ensemble de ces résultats montre que les roches-mères de la grande majorité des huiles du Mésozoïque sont situées dans le Lias, s'échelonnant depuis le Toarcien jusqu'à l'Hettangien et que les meilleures zones de potentiel pétrolier du Bassin sont localisées à l'emplacement des régions de forte subsidence à l'époque du Lias. L'étude détaillée des hydrocarbures et celle des biomarqueurs ne permettent pas de distinguer les différentes huiles entre elles, quelle que soit leur profondeur, ni de leur attribuer une origine précise à partir des différents niveaux du Lias. Les cartes de migration mettent en évidence des déplacements latéraux des hydrocarbures dans certaines roches-mères (cas du Toarcien inférieur). Elles montrent aussi un déficit important en hydrocarbures à la base du Lias (Hettangien-Sinémurien) qui apparaît comme une roche-mère potentielle des huiles du Trias. En ce qui concerne ces dernières, leurs principaux chemins de migration sont probablement les failles qui recoupent le Trias et la base du Lias qui ont pu jouer un rôle important au cours du Tertiaire (failles en distension). Une migration latérale dans les réservoirs (calcaires poreux du Dogger, grès du Trias) est envisagée. A l'est du Bassin (sud de Nancy) quelques gisements de gaz et d'huile rencontrés dans le Muschelkalk semblent avoir une origine paléozoïque (bassin Sarro-Lorrain). This article gives the main results of the geochemical survey made in the Paris Basin from cuttings and core samples coming from 100 petroleum or mining boreholes and from oil samples taken from Mesozoic reservoirs (Triassic, Upper Bathonian, Neocomian). The different geochemical methods used are pyrolysis, which is well suited for examining the numerous cuttings samples gathered, gas chromatography for the detailed analysis of oils and rock extracts, and mass spectrometry for examining biomarkers. The main times when oil and gas were formed were determined by computerized simulation using a mathematical model for the formation of hydrocarbons. Pyrolysis methods were used to compile geochemical logs of the boreholes investigated and to determine, by computing, the initial pyrolisis parameters of source rocks before their burial. In this way, within the area investigated, maps were compiled of the initial organic carbon, the total petroleum potentials and the amounts of migrated hydrocarbons. These results as a whole show that the source rocks for the great majority of the Mesozoic oils are situated in the Lias, ranging from the Toarcian to the Hettangian, and that the zones having the best petroleum potential in the Basin are located in areas of strong subsidence in Lias times. The detailed examination of the hydrocarbons and biomarkers did not distinguish different oils from each other, no matter what depth they came from, nor could these oils be attributed to a specific origin in the different levels of the Lias. The migration maps reveal lateral displacements of hydrocarbons in some source rocks (Lower Toarcian). They also show a considerable hydrocarbon deficit at the bottom of the Lias (Hettangian, Sinemurian) that appears to be a potential source rock for Triassic oils. With regard to these oils, their main migration paths were probably the faults that cut through the Triassic and the bottom of the Lias, which must have played an important role during the Tertiary (distensional faults). Lateral migration in reservoirs (porous limestone in the Dogger, sandstone in the Triassic) is considered. In the eastern part of the basin (south of Nancy), several gas and oil fields found in the Muschelkalk seem to be of Paleozoic origin (Saar-Lorraine Basin).

As digital interactions become more global, individuals who bring divergent practices 'to the keyboard' must interact with other participants who come to the digital space with different cultural norms and expectations. This study explores the interface between local expectations and global practice through emoji use in online gaming -- a venue which brings people from around the globe together on a common 'playing field'. Since emojis were originally designed to tap into universals in human experience and expression, they are a ready-made resource through which individuals can integrate their culture-based expectations with communicative norms that are rooted in the common denominators of the (global) digital environment. Using live chat data from the game streaming platform Twitch, this study examines emojis posted to the open chat room during game streams of one female and one male gamer. The analysis examines the ways that participants use these semiotic images to orient toward gaming communities of practice and claim identities within gaming groups. It also explores whether emoji use is affected by the gender of the streamer. Analysis indicates that participants in the man's stream differ from participants woman's stream in the ways they use emojis to claim community membership and employ emojis as phatic devices.