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Antiferromagnets offer a unique combination of properties including the radiation and magnetic field hardness, the absence of stray magnetic fields, and the spin-dynamics frequency scale in terahertz. Recent experiments have demonstrated that relativistic spin-orbit torques can provide the means for an efficient electric control of antiferromagnetic moments. Here we show that elementary-shape memory cells fabricated from a single-layer antiferromagnet CuMnAs deposited on a III–V or Si substrate have deterministic multi-level switching characteristics. They allow for counting and recording thousands of input pulses and responding to pulses of lengths downscaled to hundreds of picoseconds. To demonstrate the compatibility with common microelectronic circuitry, we implemented the antiferromagnetic bit cell in a standard printed circuit board managed and powered at ambient conditions by a computer via a USB interface. Our results open a path towards specialized embedded memory-logic applications and ultra-fast components based on antiferromagnets. Devices based on antiferromagnetic materials have advantages of robustness to external magnetic fields and the potential for ultrafast operation. Here the authors present a multilevel antiferromagnetic memory cell that can be operated using standard electronic interfaces.

In order to reconstruct the temperature of the North Greenland Ice Core Project (NGRIP) site, new measurements of δ15N have been performed covering the time period from the beginning of the Holocene to Dansgaard–Oeschger (DO) event 8. Together with previously measured and mostly published δ15N data, we present for the first time a NGRIP temperature reconstruction for the whole last glacial period from 10 to 120 kyr b2k (thousand years before 2000 AD) including every DO event based on δ15N isotope measurements combined with a firn densification and heat diffusion model. The detected temperature rises at the onset of DO events range from 5 °C (DO 25) up to 16.5 °C (DO 11) with an uncertainty of ±3 °C. To bring measured and modelled data into agreement, we had to reduce the accumulation rate given by the NGRIP ss09sea06bm timescale in some periods by 30 to 35%, especially during the last glacial maximum. A comparison between reconstructed temperature and δ18Oice data confirms that the isotopic composition of the stadial was strongly influenced by seasonality. We evidence an anticorrelation between the variations of the δ18Oice sensitivity to temperature (referred to as α) and obliquity in agreement with a simple Rayleigh distillation model. Finally, we suggest that α might be influenced by the Northern Hemisphere ice sheet volume.

Corticotropin releasing factor (CRF) systems in limbic structures are posited to mediate stress-induced relapse in addiction, traditionally by generating distress states that spur drug consumption as attempts at hedonic self-medication. Yet evidence suggests that activating CRF-expressing neurons in the central amygdala (CeA) or nucleus accumbens (NAc) can magnify incentive motivation in absence of distress, at least for sucrose rewards. However, traditional CRF hypotheses in addiction neuroscience are primarily directed toward drug rewards. The question remains open whether CRF systems can similarly act via incentive motivation mechanisms to promote pursuit of drug rewards, such as cocaine. Here we tested whether optogenetic excitation of CRF-containing neurons in either NAc medial shell, lateral CeA, or dorsolateral BNST of transgenic Crh -Cre+ rats would spur preference and pursuit of a particular laser-paired cocaine reward over an alternative cocaine reward, and whether excitation served as a positively-valenced incentive itself, through laser self-stimulation tests. We report that excitation of CRF-containing neurons in either NAc or CeA recruited mesocorticolimbic circuitry to amplify incentive motivation to pursue the laser-paired cocaine: focusing preference on the laser-paired cocaine reward in a two-choice task, and spurred pursuit as doubled breakpoint in a progressive ratio task. Crucially indicating positive-valence, excitation of CRF neurons in NAc and CeA also was actively sought after by most rats in self-stimulation tasks. Conversely, CRF neuronal activation in BNST was never self-stimulated, but failed to enhance cocaine consumption. Collectively, we find that NAc and CeA CRF-containing neurons can amplify pursuit and consumption of cocaine by positively-valenced incentive mechanisms, without any aversive distress.

Maladaptive decision-making is assumed to be a core feature of cocaine addiction. Indeed, numerous studies have reported deficits in non-social decision-making tasks and reward-related impulsivity in dependent cocaine users. However, social decision-making has not been examined in cocaine users yet. Moreover, it is unknown if even recreational and non-dependent cocaine use is linked to decision-making deficits. Therefore, we investigated whether recreational and dependent cocaine users exhibit alterations in social and non-social decision-making. The performance of healthy controls (n = 68), recreational cocaine users (n = 68) and dependent cocaine users (n = 30) in classical decision-making paradigms (Iowa Gambling Task, Delay Discounting) and in social interaction paradigms (Distribution Game, Dictator Game) was assessed. Decisions in the social interaction tasks of both cocaine user groups were more self-serving compared with controls as cocaine users preferred higher monetary payoffs for themselves. In the Iowa Gambling Task, only dependent cocaine users were more likely to choose disadvantageous card decks, reflecting worse decision-making. They were also more likely to choose immediate smaller rewards over larger delayed rewards in the Delay Discounting task. Our results imply that both recreational and dependent cocaine users are more concerned with their own monetary gain when interacting with another person. Furthermore, primarily dependent cocaine users are less foresighted and more impulsive regarding immediate reward. Overall, social interaction deficits are already present in recreational users, while non-social decision-making deficits occur predominantly in dependent cocaine users. Thus, social interaction training and cognitive remediation strategies may improve treatment success and quality of life in cocaine dependence.

In 12 BCE, Augustus undertook the responsibility for the calendar, which had gradually fallen out of alignment with the true dates of solstices and equinoxes. Augustus’ calendar reform, entailing the introduction of a leap day every four years, coincided with the erection of a grand meridian in the Campus Martius, known in Latin as Horologium Augusti. This device utilized the obelisk of Psamtik II (6° century BCE) as its gnomon that casted its shadow upon a travertine floor inscribed with bronze reference marks. Despite the discovery of the obelisk in 18th century and partial excavation of the floor in 1980, comprehending its geometric intricacies, regarding both dimensions and positioning, remained a challenge due to the complexities of conducting precise geomatic measurements in subterranean environments. Consequently, uncertainties persisted regarding its operational mechanics, particularly regarding whether the marks denoted days or ecliptic degrees. This study presents accurate measurements and statistically rigorous analyses that enable a precise repositioning of the meridian and a careful reconstruction of its geometry. The results suggest that the marks likely denoted specific days of the year, as recalled by Pliny the Elder. This provides support to the hypothesis that the monument functioned as an empirical validation of Augustus’ calendrical reform. In addition, the great accuracy achieved in positioning represents a fundamental aid in the desirable scenario to continue excavations of the meridian.

Dynamic management is intended to mitigate the impacts of human activities on wildlife when and where the activities overlap with at‐risk species. Amid an ever‐growing maritime industry, we researched the performance of mobile underwater passive acoustic gliders as near real‐time monitoring assets for the purpose of whale‐vessel strike mitigation through dynamic management. Across 580 glider survey days, 30 near real‐time acoustic detections of critically endangered North Atlantic right whales (NARWs) triggered 194 days of mandatory 10‐knot vessel speed limits in three Canadian Dynamic Shipping Zones (DSZs). We found a high degree of interannual and seasonal variation in NARW acoustic occurrence and vessel slowdowns in the DSZs. Gliders were more effective than aerial surveillance at triggering slowdowns by a factor of 2–5 during fall and summer but were less effective during spring. Our results provide unambiguous evidence that gliders are effective monitoring platforms that can enhance dynamic ocean management goals globally.

Abstract Large reservoirs usually present spatial gradients in fish assemblage, distinguishing three strata (littoral, pelagic, and bathypelagic) along the vertical and horizontal axes, and three zones (fluvial, transitional, and lacustrine) along the longitudinal axis. The main objective of this study was to assess if small reservoirs also present the spatial gradients in fish assemblage attributes and structure as already observed in large reservoirs. Fish surveys were conducted quarterly, from 2003 to 2008, in the Mourão Reservoir (Mourão River, Paraná, Brazil), using gillnets with different mesh sizes, arranged in all strata of all three zones. Community attributes (species richness and evenness) were calculated for each sample, and differences were tested using three-way ANOVA (factors: zone, strata, year). Community composition was summarized using Correspondence Analysis (CA) and differences were tested with three-way ANOVA for each axis, controlling the same three factors. Because of the high variability in reservoir water level through time, all analyses were made considering temporal variations. Species richness presented a decreasing trend from fluvial to lacustrine zones, and higher values in littoral strata, possibly because upper reaches and littoral regions provide better conditions for fish to feed and to reproduce. Evenness was considerably low, presenting high variability, and no evident pattern. The expected longitudinal gradient was not found in this study indicating longitudinal similarity, contrary to observed in large reservoirs. Vertical and horizontal gradients were observed in all sampling stations, indicating that abiotic and biotic conditions are influencing fish distributions within the reservoir. Resumo Grandes reservatórios, em geral, apresentam gradientes espaciais da assembleia de peixes, distinguindo três estratos (litoral, pelágico e batipelágico) ao longo dos eixos vertical e horizontal, e três zonas (fluvial, transição e lacustre) ao longo do eixo longitudinal. O principal objetivo deste estudo foi avaliar se pequenos reservatórios também apresentam tais gradientes espaciais, nos atributos e na estrutura da assembleia de peixes, como já observado em grandes reservatórios. As coletas dos peixes foram realizadas trimestralmente, de 2003 a 2008, no reservatório de Mourão (Rio Mourão, Paraná, Brasil), com redes de espera com diferentes tamanhos de malha, dispostas em todos os estratos de todas as três zonas. Atributos da assembleia (riqueza de espécies e equitabilidade) foram calculados para cada amostra, e as diferenças foram testadas utilizando ANOVA tri-fatorial (fatores: zona, estratos, anos). A estrutura da assembleia foi sumarizada usando uma Análise de Correspondência (CA) e as diferenças foram testadas com ANOVA tri-fatorial para cada eixo, controlando os mesmos três fatores. Devido à alta variabilidade no nível da água do reservatório ao longo do tempo, todas as análises foram feitas considerando as variações temporais. A riqueza de espécies apresentou tendência decrescente, da zona fluvial até a lacustre, com valores maiores no estrato litoral, possivelmente porque locais à montante e regiões litorâneas proporcionam melhores condições de alimentação e reprodução para os peixes. A equitabilidade foi consideravelmente baixa, apresentando alta variabilidade e nenhum padrão evidente. O gradiente longitudinal esperado não foi encontrado neste estudo, indicando similaridade longitudinal, ao contrário do observado em grandes reservatórios. Gradientes verticais e horizontais foram observadas em todas as áreas amostradas, sugerindo que as condições bióticas e abióticas estão influenciando a distribuição dos peixes ao longo do reservatório.

Acute kidney injury (AKI) following hyperthermic intraperitoneal chemotherapy (HIPEC) is common. Identifying patients at risk could have implications for surgical and anesthetic management. We aimed to develop a predictive model that could predict AKI based on patients’ preoperative characteristics and intraperitoneal chemotherapy regimen. We retrospectively gathered data of adult patients undergoing HIPEC at our health system between November 2013 and April 2022. Next, we developed a model predicting postoperative AKI using multivariable logistic regression and calculated the performance of the model (area under the receiver operating characteristics curve [AUC]) via tenfold cross-validation. A total of 412 patients were included, of which 36 (8.7%) developed postoperative AKI. Based on our multivariable logistic regression model, multiple preoperative and intraoperative characteristics were associated with AKI. We included the total intraoperative cisplatin dose, body mass index, male sex, and preoperative hemoglobin level in the final model. The mean area under the receiver operating characteristics curve value was 0.82 (95% confidence interval 0.71–0.93). Our risk model predicted AKI with high accuracy in patients undergoing HIPEC in our institution. The external validity of our model should now be tested in independent and prospective patient cohorts.

Risk stratification for hospitalized adults with COVID-19 is essential to inform decisions about individual patients and allocation of resources. So far, risk models for severe COVID outcomes have included age but have not been optimized to best serve the needs of either older or younger adults. Models also need to be updated to reflect improvements in COVID-19 treatments. This retrospective study analyzed data from 6906 hospitalized adults with COVID-19 from a community health system across five states in the western United States. Risk models were developed to predict mechanical ventilation illness or death across one to 56 days of hospitalization, using clinical data available within the first hour after either admission with COVID-19 or a first positive SARS-CoV-2 test. For the seven-day interval, models for age ≥ 18 and < 50 years reached AUROC 0.81 (95% CI 0.71–0.91) and models for age ≥ 50 years reached AUROC 0.82 (95% CI 0.77–0.86). Models revealed differences in the statistical significance and relative predictive value of risk factors between older and younger patients including age, BMI, vital signs, and laboratory results. In addition, for hospitalized patients, sex and chronic comorbidities had lower predictive value than vital signs and laboratory results.

Background Completeness of cytoreduction is a significant predictor of long-term outcome after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Imaging has limited sensitivity to identify peritoneal metastases and therefore predict whether complete cytoreduction is possible. We reviewed our experience using laparoscopy to determine candidates for complete cytoreduction and HIPEC. Methods This single-center, retrospective study examined patients from 2007 to 2014 who underwent laparoscopy to determine complete cytoreduction (CC-0/1)/HIPEC candidacy. Preoperative, intraoperative, and postoperative data were collected. Results A total of 145 laparoscopies were performed on 141 patients, 72 (51.1 %) of whom were female, with a median age of 53 years (range 20–79). The primary site was appendiceal in 67 (47.5 %) patients, colorectal in 43 (30.5 %), mesothelioma in 17 (12.1 %), unknown in 9 (6.4 %), small bowel in 3 (2.1 %), gastric in 1, and ovarian in 1 (0.7 % each). Overall, 115 (81.6 %) patients had prior abdominal surgery, 111 (76.6 %) had evidence of disease on imaging, and 117 (80.7 %) underwent prior chemotherapy, with a median of 5.9 weeks between the last treatment and laparoscopy (0.9–498.9 weeks). Four (2.8 %) intraoperative complications were observed (one liver laceration, two enterotomies, and one air embolus), and nine (6.2 %) postoperative complications [four (2.8 %) Clavien grade (CG) I, three (2.8 %) CG II, one (0.7 %) CG III (return to operating room) and one (0.7 %) CG IV (transient ischemic attack)]. Forty-eight patients deemed candidates by laparoscopy underwent CRS/HIPEC (positive predictive value 82.8 %). Conclusion Diagnostic laparoscopy is a safe, feasible, and accurate staging tool in patients with suspected peritoneal metastases being considered for CRS.