Browse Articles

Ultraviolet and biological effective dose observations at Gale Crater, Mars

The incident ultraviolet (UV) irradiance on the surface of Mars is strongly sterilizing and plays a critical role in atmospheric and near-surface photochemistry. The Rover Environmental Monitoring Station (REMS) instrument, which includes the first UV sensor sent to Mars on board the Curiosity rover, has been measuring the UV irradiance at Gale Crater since 2012, providing ground-truth data regarding seasonal and short-term variability of the UV radiation at the surface of another planet. Here, we analyze the REMS UV measurements for a period of >5 Martian years to retrieve biological effective doses and other UV radiation quantities on the planetary surface that are key for different physicochemical processes. Our results reveal a previously unidentified complex UV radiation environment on the Martian surface, with dramatic short-term fluctuations capable of changing UV radiation doses by >30% in a few sols. We assess the viability of terrestrial microorganisms exposed to this UV radiation field and dispersed through the Martian atmosphere from a robotic spacecraft or human habitat. Our findings show that reducing microbial viability by 99% would require several hours of exposure to the Martian environment including during the daytime, a finding that may call for a reinforcement of planetary protection policies.

Endocannabinoids disinhibit the ventral tegmental nucleus of Gudden to dorsal premammillary nucleus pathway to enhance escape behavior following learned threat experience

Seasonal pattern of preterm birth in the Netherlands: A population-based retrospective cohort study

Background Prior research has demonstrated the impact of environmental influences, including seasonal patterns, as determinants of preterm birth, although relationships vary. This study aims to determine whether there is an association between month of conception and preterm birth or gestational age at birth in the Netherlands. Methods This was a population-based retrospective cohort study with data collected between 2015–2019. Data originated from the national perinatal registry in The Netherlands, of which 828,574 deliveries were included. Relationships between month of conception and birth with gestational age at delivery were investigated. Furthermore, trends in the preterm birth rate among women diagnosed with imminent preterm birth were investigated. Additionally, the relationship between outdoor temperature, humidity, hours of sunlight with preterm birth was examined to investigate their possible role in preterm birth’s pathophysiology. Results The distribution of gestational age at birth showed significant variation over the months of conception when all births, spontaneous onset of delivery, or iatrogenic onset of delivery were considered (all p < 0.001). Preterm and term births were more common for conception between January and June, whereas birth >41 weeks of gestation was most common for conception between July and December. Seasonal or monthly variation in preterm birth rate among women diagnosed with imminent preterm birth was not significant (p = 0.103). Higher humidity was associated with higher preterm birth rates (HR = 1.003, 95% CI: 1.001–1.005), whereas higher outdoor temperature (HR = 0.998, 95% CI: 0.996–1.000) and more sunlight exposure (HR = 0.994, 95% CI: 0.995–0.998) were associated with lower preterm birth rates. Conclusions Pregnancies conceived in January through June are associated with a higher risk of preterm birth. These outcomes demonstrate a seasonal pattern and identify environmental risk factors for preterm birth. These patterns might be a result of fluctuations in melatonin levels, governed by variation in the hours of daily sunshine over the year in the Netherlands.

Real-time imaging of blood coagulation and angiogenesis during development in a zebrafish model of type I antithrombin deficiency

Ferroptosis-activating metabolite acrolein antagonizes necroptosis and anti-cancer therapeutics

“Everything had stopped, no meeting, no gathering”: Social interactions during the COVID-19 pandemic in the Central African Republic, the Democratic Republic of Congo, and Bangladesh

Understanding the spread of COVID-19 in humanitarian and fragile settings is challenging for many reasons, including the lack of data on social dynamics and preventive behaviors during an epidemic. We investigate social interactions in three such settings - Democratic Republic of the Congo (DRC), Central African Republic (CAR), Cox’s Bazar (CXB), Bangladesh – and how they changed during the first year of the pandemic. This comparative mixed-methods study uses a representative household survey and focus group discussions or key informant interviews in each site. Descriptive weighted analysis of survey responses was conducted; multivariate logistic regression identified factors associated with changes in social interactions. Thematic analysis was conducted on qualitative data. Nearly all participants had social interactions the day before the survey, although the average number of daily interactions was low. Interactions primarily occurred indoors, at home and without masks. We saw a discrepancy between knowledge about and practice of preventive behaviors. Most respondents reported interacting less often (77.3% CXB, 86.7% CAR, 58.8% DRC) and having shorter meetings (80% CXB, 77.8% CAR, and 47.8% DRC). Reluctance towards the COVID-19 vaccine was a risk factor for non-compliant behaviors in CAR (OR increased frequency = 3.51, 95%CI = 1.41–8.75; OR increased duration = 2.47, 95%CI = 1.15–5.29) and DRC (OR increased duration = 3.06, 95%CI = 1.71–5.49), likely pointing to distrust towards institutional policies. Respondents from IDP communities in DRC were less likely to reduce the frequency of interaction, likely because living conditions did not facilitate physical distancing. Increased knowledge in CXB was associated with compliant behavior (for 1pt-increase: OR increased frequency = 0.47, 95%CI = 0.32–0.68; OR increased duration = 0.46, 95%CI = 0.31–0.69). Understanding social dynamics is fundamental to predict infectious disease spread, particularly in humanitarian settings. More evidence is needed to understand behaviors influencing disease dynamics and drivers of behaviors, including trust in authorities, social, and economic factors. Peace, community engagement, and reduction of misinformation remain critical for epidemic responses in humanitarian settings.

In-vivo assessment of vascular endothelial injury in a rat model of unilateral carotid artery injury using 4D-flow MRI

Expression of an interleukin-2 partial agonist enhances regulatory T cell persistence and efficacy in mouse autoimmune models

Genome-wide scan for signatures of selection in Hanwoo and Angus cattle using whole-genome sequence data

This study used whole-genome sequence data on 406 beef cattle (203 Hanwoo and 203 Angus) to detect signatures of selection using four different methods; integrated haplotype score (iHS), Rsb, XP-EHH, and runs of homozygosity (ROH). Based on Rsb and XP-EHH analysis, 36 and 21 genomic regions differed significantly between Angus and Hanwoo breeds. Within breeds, we identified 108 regions (76 in Hanwoo and 32 in Angus) with the ROH analysis and 331 regions with the iHS method (298 in Hanwoo and 33 in Angus). The candidate genes related to meat quality, such as HSPA9 and LPL, were found within Hanwoo, while genes associated with growth and meat quantity traits, including ACTC1 and TMEM68, were identified within Angus. This study can assist in understanding the selection history of these breeds and identifying the genomic regions associated with the traits selected for in the breeding programs for these cattle breeds.

Pre conception dyslipidemia and risk for preeclampsia in women undergoing IVF ET

Coherently confined single-metal-atom chains in 2D semiconductors

High prevalence of low-concentration antimicrobial residues in commercial fish: A public health concern in Bangladesh

Antibiotics are widely used in commercial fish farms in Bangladesh for therapeutic and prophylactic purpose, raising concerns about antimicrobial resistance (AMR) and environmental contamination. This study used Thin Layer Chromatography to detect antimicrobial residues in four commercially available fish species- Tilapia (Oreochromis aureus), Stinging catfish (Heteropneustes fossilis), Climbing perch (Anabas testudineus), and Pabda (Ompok pabda)—with 100 samples per species. Ultra High-Performance Liquid Chromatography quantified residues in a subset of 25 samples per species. The prevalence of Ciprofloxacin, Oxytetracycline, and Chlortetracycline residues varied significantly among fish species, with the highest prevalence observed for Ciprofloxacin in Tilapia (42%), Oxytetracycline in Pabda (41%), and Chlortetracycline in Tilapia (49%). Additionally, the prevalence of Levofloxacin and Chlortetracycline differed by sampling location, with the highest levels found in Jhawtala market, 27.5% for Levofloxacin and 53.8% for Chlortetracycline. Furthermore, residue concentrations were highest for Enrofloxacin in Climbing perch (69.32 µg/Kg) and Oxytetracycline in Pabda (88.73 µg/Kg). The highest Hazard Quotient (HQ) was for Enrofloxacin in Climbing perch (0.480), followed by Pabda (0.460), Stinging catfish (0.420), and Tilapia (0.387). While the HQ values were below 1.0, indicating no immediate toxicological risk, residues raise public health concerns due to the chance of potential AMR development. Further research is needed on antimicrobial bioaccumulation, indirect exposure sources, environmental contamination, and antimicrobial resistance in aquaculture and wild fish.

The role of self-care and self-compassion in networks of resilience and stress among healthcare professionals

Abstract Healthcare professionals (HCPs) are essential for maintaining our healthcare system but are at risk for developing mental health issues due to chronic occupational stress. This can lead to a vicious cycle with extended sick leave, increased workloads for colleagues, and strain on the healthcare system. Therefore, preventive interventions aiming at enhancing resilience - the maintenance of mental health despite stress - are essential. Yet, identifying the most impactful resilience factors has been challenging. To explore the relationships between resilience factors, stress, mental health, and work-related outcomes, we conducted regularized partial correlation network analyses focusing on self-care and self-compassion. Cross-sectional data from HCPs in Germany were collected in April 2023. Analyses of 212 HCPs (age 41.63 [21–68] years; 81.60% women) revealed self-compassion as the most important factor across all networks, while the importance of self-care showed through individual connections to crucial factors like mental health problems and work-life balance. Work engagement, contrary to burnout, was closely interrelated with resilience factors. In conclusion, despite accounting for established evidence-based resilience factors, self-compassion and self-care seem crucial in the context of stress and mental health in HCPs. More research is needed to validate the causal importance of self-care and self-compassion.

Author Correction: Deglacial release of petrogenic and permafrost carbon from the Canadian Arctic impacting the carbon cycle

Key stakeholders’ views on the causes of medicine stock-outs in Mauritania: A qualitative study

The number of medicine stock-outs is increasing globally. In Mauritania, they are recurring, although, to our knowledge, no study has yet been conducted to determine the causes. Therefore, this qualitative study aims to explore the views of key stakeholders in the pharmaceutical sector to identify the main local or national causes of stock-outs. It will thus provide a common understanding and guide policy-makers towards corrective action. The study was carried out in five health districts and at the regional and central levels. The samples were purposive. Two focus groups and twenty semi-structured individual interviews were held with 38 participants, including health professionals, managers from the Central Purchasing Office for Essential Medicines and Consumables, the Pharmacy and Laboratory Department and the Ministry of Health. All interviews were recorded and transcribed. A thematic content analysis was carried out. Our findings indicate the national causes of medicine stock-outs at three healthcare system levels (operational, regional, and central). They were grouped into five categories: insufficient human resource capacity (number of staff, training, retention), communication and coordination problems between stakeholders, logistical constraints (transport, storage), financial constraints, inadequate forecasting of needs, and complex procurement procedures. These causes of medicine stock-outs are interconnected, and many could be addressed locally through solutions initiated and led by the Mauritanian authorities. To address medicine stock-outs sustainably, we suggest and discuss some possible actions, including reforms to improve Central Purchasing Office for Essential Medicines and Consumables’s governance and accountability and, more broadly, to strengthen the various pillars of the local health and pharmaceutical system.

The effect of a synthetic cannabinoid agonist (nabilone) on unimodal tactile illusion correlates with a psychometric scores in healthy volunteers

Abstract Our previous studies showed that dexamphetamine, an indirect dopamine agonist, widens Stimulus Binding Windows (BWs) in healthy subjects. The present study aimed to investigate the effect of nabilone, a synthetic cannabinoid agonist, on the BWs in a unimodal illusion: the tactile funneling illusion (TFI). The study also aimed to study the association between tactile illusion with psychometric scores. Healthy participants (n = 32) completed the TFI at various delays and distances of separation of stimuli after receiving nabilone (2–4 mg, PO) or placebo in a randomized, double-blind, counterbalanced, crossover manner. The primary illusory measures were funneling and errors of localisation (EL). Three physiological and five psychometric measurements were also performed. The results showed that nabilone decreased funneling in a delay-dependent manner ( p  = 0.0016), whereby funneling was reduced at 0 ms ( p  = 0.01). Nabilone also significantly reduced EL in a distance-dependent manner ( p  = 0.038). Nabilone increased ratings on two of the five administered psychometric scales ( p  < 0.05), without significantly changing the overall (average) scores. However, there were associations between the overall psychometric scores and funneling under the strongest (0 ms delay) illusion condition, which is dependent on the drug condition (nabilone ρ  = 0.45, p  = 0.028). To conclude, unlike the effects of dexamphetamine, low activation of the cannabinoid system decreases the illusory perception of funneling, with narrowing spatial BWs.

Interlayer engineering of lattice dynamics and elastic constants of 2D layered nanomaterials under pressure

The weekend effect on 28-day mortality in septic patients admitted to the ICU: A retrospective study from the MIMIC-IV database

Objective Numerous studies have shown that patients admitted on weekends or holidays have higher mortality rates and poorer prognoses than those admitted on weekdays. However, the specific impact of the weekend effect on patients with sepsis remains unclear and requires further investigation. Methods This study included adult patients with sepsis who were first admitted to the ICU and stayed for ≥24 hours, using data from the Medical Information Mart for Intensive Care (MIMIC)-IV (version 2.2),with the data collection period from 2008 to 2019. Data on age, gender, type of ICU admission, vital signs, disease severity scores, and medications were collected, with patients categorized into weekend and weekday admission groups. The primary outcome was 28-day mortality, while secondary outcomes included 90-day mortality, hospital mortality, ICU mortality, and survival days without vasoactive drugs, ventilator, or ICU stay. COX regression analyses with propensity score matching (PSM) were employed to assess the impact of weekend admissions on the survival of septic patients in the ICU. Results A total of 20,261 septic patients met the inclusion criteria, with 14,469 in the weekday group and 5,792 in the weekend group. The weekend admission group showed no statistically significant differences in 28-day mortality, hospital mortality, ICU mortality, survival days without vasoactive drugs, survival days without ventilator, survival days without ICU, and length of ICU stay compared to the weekday group. Subgroup analyses for 28-day mortality revealed that key baseline characteristics such as gender, age, BMI, race, ICU type, hypertension, diabetes mellitus, and SOFA score did not independently influence the prognosis of patients with sepsis based on weekend admission. Conclusion The study found no significant weekend effect on the prognosis of septic patients admitted to the ICU, based on both univariate and multivariate analyses.

Host range and virulence of Metarhizium pingshaense against Chilo species and expression of fungal virulence genes in Conogethes punctiferalis

Expedient access to bora-butenolide bioisosteres by counteranion-mediated trans-hydroboration of alkynes

Abstract The hydroboration of alkynes is a textbook example of a syn-selective concerted addition reaction, while trans-selective additions of borane to alkynes remain to be developed. We herein report a transition metal-free anti-addition of pinacolborane to alkynes, facilitated by the counteranion effect. This work further develops Chan alkyne reduction by utilizing the borane instead of aluminohydride reagents, enabling the facile synthesis of valuable five-membered boracycles that constitute isosteric alternatives to bioactive butenolides and a versatile platform for abundant downstream transformations. The practical method is distinguished by excellent regioselectivity, a broad substrate scope, and high compatibility with a variety of functional groups. The exploration of trans-selective patterns affords not only a stereo-complementary approach to traditional organic synthesis, but also mandates a new perspective on the noncanonical trans-hydroboration mechanism. A combination of control experiments and computational studies at the DFT level of theory reveal the previously unrecognized role of the HMDS counteranion in a stepwise intermolecular hydrogen transfer process.