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Nearby star-forming regions are ideal laboratories to study high-energy emission of different stellar populations, from very massive stars to brown dwarfs. NGC 2023 is a reflection nebula situated to the south of the Flame Nebula (NGC 2024) and at the edge of the H ii region IC 434, which also contains the Horsehead Nebula (Barnard 33). NGC 2023, NGC 2024, Barnard 33 and the surroundings of the O-type supergiant star ζ Ori constitute the south part of the Orion B molecular complex. In this work, we present a comprehensive study of X-ray emitters in the region of NGC 2023 and its surroundings. We combine optical and infrared data to determine physical properties (mass, temperature, luminosity and the presence of accretion discs) of the stars detected in an XMM–Newton observation. This study has allowed us to analyse spectral energy distribution of these stars for the first time and determine their evolutionary stage. Properties of the X-ray emitting plasma of these stars are compared to those found in other nearby star-forming regions. The results indicate that the stars that are being formed in this region have characteristics, in terms of physical properties and luminosity function, similar to those found in the Taurus–Auriga molecular complex. [ABSTRACT FROM AUTHOR]

This paper analyses the behaviour of five rainfall indicators (maximum intensity, cumulative rainfall, irregularity, probability of rain and persistence of rain) over different observation timescales ranging from 5 min to 24 h. It covers a large area on the Mediterranean side of the Iberian Peninsula (River J&uuacute;car Water Authority, 43 000 km²) on a continuous basis over a period of 14 years (1994-2007). The results show that the behaviour of extreme Mediterranean rainfall is heavily dependent on the observation timescale. There are a number of turning points in the indicator trends which occur on different timescales (1 and 6 h in the case of rain intensity and irregularity, 6 h for cumulative rainfall and between 15 and 30 min for the persistence of rain) and may be relevant for the determination of thresholds used in water management. [ABSTRACT FROM AUTHOR]

A protein binding to the uto egulatory lement (ARE) upstream of the regulatory ccaR gene of Streptomyces clavuligerus was isolated previously by DNA affinity binding. The areB gene, encoding this protein, is located upstream and in opposite orientation to the leuCD operon of S. clavuligerus; it encodes a 239-amino-acid protein of the IclR family with a helix–turn–helix motif at the N-terminal region. An areB-deleted mutant, S. clavuligerusΔ areB, has been constructed by gene replacement. This strain requires leucine for optimal growth in defined media. Expression of the leuCD operon is retarded in S. clavuligerusΔ areB, because AreB binds the areB-leuCD intergenic region acting as a positive modulator. Clavulanic acid and cephamycin C production are improved in the Δ areB mutant although no drastic difference in ccaR expression was observed. Pure recombinant AreB protein does not bind the ARE ccaR sequence (as shown by EMSA) unless filtered extracts from S. clavuligerus ATCC 27064-containing molecules of Mr lower than 10 kDa are added to the binding reaction. Restoration of binding to the ARE ccaR sequence is not observed when filtered extracts are obtained from the Δ areB mutant, suggesting that biosynthesis of the small-molecular-weight effector is also controlled by AreB. [ABSTRACT FROM AUTHOR]

The Wells-Riley model has been widely used to estimate airborne infection risk, typically from a deterministic point of view (i.e., focusing on the average number of infections) or in terms of a per capita probability of infection. Some of its main limitations relate to considering well-mixed air, steady-state concentration of pathogen in the air, a particular amount of time for the indoor interaction, and that all individuals are homogeneous and behave equally. Here, we revisit the Wells-Riley model, providing a mathematical formalism for its stochastic version, where the number of infected individuals follows a Binomial distribution. Then, we extend the Wells-Riley methodology to consider transient behaviours, randomness, and population heterogeneity. In particular, we provide analytical solutions for the number of infections and the per capita probability of infection when: (i) susceptible individuals remain in the room after the infector leaves, (ii) the duration of the indoor interaction is random/unknown, and (iii) infectors have heterogeneous quanta production rates (or the quanta production rate of the infector is random/unknown). We illustrate the applicability of our new formulations through two case studies: infection risk due to an infectious healthcare worker (HCW) visiting a patient, and exposure during lunch for uncertain meal times in different dining settings. Our results highlight that infection risk to a susceptible who remains in the space after the infector leaves can be nonnegligible, and highlight the importance of incorporating uncertainty in the duration of the indoor interaction and the infectivity of the infector when estimating risk., (© 2024 The Authors. Risk Analysis published by Wiley Periodicals LLC on behalf of Society for Risk Analysis.)

Background: It is known that the immune system is dysregulated in schizophrenia, having a state similar to chronic neuroinflammation. The origin of this process is unknown, but it is known that T and B lymphocytes, which are components of the adaptive immune system, play an important role in the pathogenic mechanisms of schizophrenia., Methods: We analysed the membrane of PBMCs from patients diagnosed with schizophrenia through proteomic analysis (n = 5 schizophrenia and n = 5 control). We found the presence of the Kv1.3 voltage-gated potassium channel and its auxiliary subunit β1 (KCNAB1) and β2 (KCNAB2). From a sample of 90 participants, we carried out a study on lymphocytes with whole-cell patch-clamp experiments (n = 7 schizophrenia and n = 5 control), western blot (n = 40 schizophrenia and n = 40 control) and confocal microscopy to evaluate the presence and function of different channels. Kv in both cells., Results: We demonstrated the overexpression of Kv1.1, Kv1.2, Kv1.3, Kv1.6, Kv4.2, Kv4.3 and Kv7.2 channels in PBMCs from patients with schizophrenia. This study represents a groundbreaking exploration, as it involves an electrophysiological analysis performed on T and B lymphocytes from patients diagnosed of schizophrenia compared to healthy participants. We observed that B lymphocytes exhibited an increase in output current along with greater peak current amplitude and voltage conductance curves among patients with schizophrenia compared with healthy controls., Conclusions: This study showed the importance of the B lymphocyte in schizophrenia. We know that the immune system is altered in schizophrenia, but the physiological mechanisms of this system are not very well known. We suggest that the B lymphocyte may be relevant in the pathophysiology of schizophrenia and that it should be investigated in more depth, opening a new field of knowledge and possibilities for new treatments combining antipsychotics and immunomodulators. The limitation is that all participants received antipsychotic medication, which may have influenced the differences observed between patients and controls. This implies that more studies need to be done where the groups can be separated according to the antipsychotic drug., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The loss of vestibular and motor function can occur naturally with aging. Vestibular physiotherapy exercises (VE) specifically address vestibular rehabilitation to reduce imbalances and improve physical condition, like therapeutic exercise (TE). During COVID-19, technology was used with the elderly for implementation. Objective: to determine if vestibular exercises are as effective as multicomponent exercises in improving functional capacity using technological tools. Methods: A randomized clinical trial compared two intervention groups of 21 subjects with functional limitations and frailty (average age 76.11 years). The intervention involved multicomponent exercise for the control group (Vivifrail protocol) and vestibular exercises for the experimental group (Cawthorne and Cooksey exercises) for 6 weeks with five sessions per week both groups. Two professionals implemented the exercises, and participants received tailored exercise videos. Primary outcomes were gait speed, dynamic balance, and physical capacity. Results : Both groups showed significant improvements. For physical function measured by SPPB (0-12 points), the multicomponent exercise group improved by 1.97 (0.91; 3.03), p < 0.001, and the vestibular exercise group improved by 1.63 (0.65; 2.60), p = 0.002. For dynamic balance measured by the Timed Up and Go (TUG) test, the multicomponent exercise group improved by -0.88 (-1.33; -0.42), p < 0.001, and the vestibular exercise group improved by -0.79 (-1.21; -0.37), p < 0.001. There were no significant differences between groups. Finally, regarding gait speed, there were no differences in either group between pretest and post-test ( p > 0 .05). Conclusions: Both multicomponent exercise and vestibular exercises improve functional capacities via telerehabilitation as measured by the SPPB, although vestibular physiotherapy does not show superior outcomes compared to the control group.

Division and differentiation events by which cell populations with specific functions are generated often take place as part of a developmental programme, which can be represented by a sequence of compartments. A compartment is the set of cells with common characteristics; sharing, for instance, a spatial location or a phenotype. Differentiation events are transitions from one compartment to the next. Cells may also die or divide. We consider three different types of division events: (i) where both daughter cells inherit the mother's phenotype (self-renewal), (ii) where only one of the daughters changes phenotype (asymmetric division), and (iii) where both daughters change phenotype (symmetric division). The self-renewal probability in each compartment determines whether the progeny of a single cell, moving through the sequence of compartments, is finite or grows without bound. We analyse the progeny stochastic dynamics with probability generating functions. In the case of self-renewal, by following one of the daughters after any division event, we may construct lifelines containing only one cell at any time. We analyse the number of divisions along such lines, and the compartment where lines terminate with a death event. Analysis and numerical simulations are applied to a five-compartment model of the gradual differentiation of hematopoietic stem cells and to a model of thymocyte development: from pre-double positive to single positive (SP) cells with a bifurcation to either SP4 or SP8 in the last compartment of the sequence., (© 2024. The Author(s).)

Background: Bile duct injury (BDI) repair surgery is usually associated with morbidity/mortality. The neutrophil-to-lymphocyte ratio (NLR) easily assesses a patient's inflammatory status. The study aims to determine the possible relationship between preoperative NLR (pNLR) with postoperative outcomes in BDI repair surgery., Methods: Approved Ethics/Research Committee retrospective study, in patients who had a Bismuth-Strasberg type E BDI repair (2008-2023). Data registered was: morbidity, mortality, and long-term outcomes (primary patency and loss of primary patency) (Kaplan-Meier). Group comparison (U Mann-Whitney), receiver operator characteristic (ROC): area under curve [AUC]; cut-off value, and Youden index [J], and logistic regression analysis were used for pNLR evaluation., Results: Seventy-three patients were studied. Mean age was 44.4 years. E2 was the commonest BDI (38.4%). Perioperative morbidity/mortality was 31.5% and 1.4%. Primary patency was 95.9%. 8.2% have lost primary patency (3-year actuarial patency: 85.3%). Median pNLR was higher in patients who had any complication (4.84 vs. 2.89 p = 0.015), biliary complications (5.29 vs. 2.86 p = 0.01), and patients with loss of primary patency (5.22 vs. 3.1 p = 0.08). AUC's, cut-off values and (J) were: any complication (0.678, pNLR = 4.3, J = 0.38, p = 0.007), serious complication (0.667, pNLR = 4.3, J = 0.34, p = 0.04), biliary complications (0.712, pNLR = 3.64, J = 0.46, p = 0.001), and loss of primary patency (0.716, pNLR = 3.24, J = 0.52, p = 0.008). Logistic regression was significant in any complication (Exp [B]: 0.1, p = 0.002), serious complications (Exp [B]: 0.2, p = 0.03), and biliary complications (Exp [B]: 8.1, p = 0.003)., Conclusions: pNLR is associated with complications in BDI repair with moderate to acceptable predictive capacity. pNLR could potentially predict patency of a BDI repair., (© 2024 Royal Australasian College of Surgeons.)

Background: Many UK hospitals rely heavily on natural ventilation as their main source of airflow in patient wards. This method of ventilation can have cost and energy benefits, but it may lead to unpredictable flow patterns between indoor spaces, potentially leading to the unexpected transport of infectious material to other connecting zones. However, the effects of weather conditions on airborne transmission are often overlooked., Methods: A multi-zone CONTAM model of a naturally ventilated hospital respiratory ward, incorporating time-varying weather, was proposed. Coupling this with an airborne infection model, this study assessed the variable risk in interconnected spaces, focusing particularly on occupancy, disease and ventilation scenarios based on a UK respiratory ward., Results: The results suggest that natural ventilation with varying weather conditions can cause irregularities in the ventilation rates and interzonal flow rates of connected zones, leading to infrequent but high peaks in the concentration of airborne pathogens in particular rooms. This transient behaviour increases the risk of airborne infection, particularly through movement of pathogens between rooms, and highlights that large outbreaks may be more likely under certain conditions. This study demonstrated how ventilation rates achieved by natural ventilation are likely to fall below the recommended guidance, and that the implementation of supplemental mechanical ventilation can increase ventilation rates and reduce the variability in infection risks., Conclusion: This model emphasises the need for consideration of transient external conditions when assessing the risk of transmission of airborne infection in indoor environments., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aims: To monitor severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA contamination in vehicles operating in England during the pandemic, to better understand transmission risk of SARS-CoV-2 on public transport., Methods and Results: We collected 1314 surface samples between December 2020 and April 2022 on trains and buses managed by five different transport operators. The presence of SARS-CoV-2 RNA was investigated through reverse transcription polymerase chain reaction (RT-PCR). SARS-CoV-2 RNA was found on 197 (15%) of the 1314 surfaces sampled, including seat head rests, handholds, and air extract grilles, but the levels of RNA recovered on those samples (median value of 23.4, interquartile range: 14.3-35.4, N gene copies per extraction) made the presence of infectious virus at the time of sampling extremely unlikely. However, detection rates varied over time with peaks broadly coinciding with times of high community transmission, when it was more likely that people infected with SARS-CoV-2 were travelling on public transport., Conclusion: During the pandemic, and as in other public spaces, low levels of SARS-CoV-2 RNA were found on surfaces associated with public transport., (© Crown copyright 2024.)

Protective antigen (PA) is a protein produced by Bacillus anthracis. It forms part of the anthrax toxin and is a key immunogen in US and UK anthrax vaccines. In this study, we have conducted experiments to quantify PA in the supernatants of cultures of B. anthracis Sterne strain, which is the strain used in the manufacture of the UK anthrax vaccine. Then, for the first time, we quantify PA production and degradation via mathematical modelling and Bayesian statistical techniques, making use of this new experimental data as well as two other independent published data sets. We propose a single mathematical model, in terms of delay differential equations (DDEs), which can explain the in vitro dynamics of all three data sets. Since we did not heat activate the B. anthracis spores prior to inoculation, germination occurred much slower in our experiments, allowing us to calibrate two additional parameters with respect to the other data sets. Our model is able to distinguish between natural PA decay and that triggered by bacteria via proteases. There is promising consistency between the different independent data sets for most of the parameter estimates. The quantitative characterisation of B. anthracis PA production and degradation obtained here will contribute towards the ambition to include a realistic description of toxin dynamics, the host immune response, and anti-toxin treatments in future mechanistic models of anthrax infection., (© 2024. The Author(s).)

We consider stochastic models of individual infected cells. The reproduction number, R , is understood as a random variable representing the number of new cells infected by one initial infected cell in an otherwise susceptible (target cell) population. Variability in R results partly from heterogeneity in the viral burst size (the number of viral progeny generated from an infected cell during its lifetime), which depends on the distribution of cellular lifetimes and on the mechanism of virion release. We analyse viral dynamics models with an eclipse phase: the period of time after a cell is infected but before it is capable of releasing virions. The duration of the eclipse, or the subsequent infectious, phase is non-exponential, but composed of stages. We derive the probability distribution of the reproduction number for these viral dynamics models, and show it is a negative binomial distribution in the case of constant viral release from infectious cells, and under the assumption of an excess of target cells. In a deterministic model, the ultimate in-host establishment or extinction of the viral infection depends entirely on whether the mean reproduction number is greater than, or less than, one, respectively. Here, the probability of extinction is determined by the probability distribution of R , not simply its mean value. In particular, we show that in some cases the probability of infection is not an increasing function of the mean reproduction number.

Diversity of the naive T cell repertoire is maintained by competition for stimuli provided by self-peptides bound to major histocompatibility complexes (self-pMHCs). We extend an existing bi-variate competition model to a multi-variate model of the dynamics of multiple T cell clonotypes which share stimuli. In order to understand the late-time behaviour of the system, we analyse: (i) the dynamics until the extinction of the first clonotype, (ii) the time to the first extinction event, (iii) the probability of extinction of each clonotype, and (iv) the size of the surviving clonotypes when the first extinction event takes place. We also find the probability distribution of the number of cell divisions per clonotype before its extinction. The mean size of a new clonotype at quasi-steady state is an increasing function of the stimulus available to it, and a decreasing function of the fraction of stimuli it shares with other clonotypes. Thus, the probability of, and time to, extinction of a new clonotype entering the pool of T cell clonotypes is determined by the extent of competition for stimuli it experiences and by its initial number of cells., (© 2023. The Author(s).)

In order to effectively balance enforced guidance/regulation during a pandemic and limit infection transmission, with the necessity for public transportation services to remain safe and operational, it is imperative to understand and monitor environmental conditions and typical behavioural patterns within such spaces. Social distancing ability on public transport as well as the use of advanced computer vision techniques to accurately measure this are explored in this paper. A low-cost depth-sensing system is deployed on a public bus as a means to approximate social distancing measures and study passenger habits in relation to social distancing. The results indicate that social distancing on this form of public transport is unlikely for an individual beyond a 28% occupancy threshold, with an 89% chance of being within 1-2 m from at least one other passenger and a 57% chance of being within less than one metre from another passenger at any one point in time. Passenger preference for seating is also analysed, which clearly demonstrates that for typical passengers, ease of access and comfort, as well as seats having a view, are preferred over maximising social-distancing measures. With a highly detailed and comprehensive set of acquired data and accurate measurement capability, the employed equipment and processing methodology also prove to be a robust approach for the application.

The retention capacity of natural calcareous gravels used as a filling material between the packages containing radioactive waste materials in the disposal cells was evaluated for Sr, U, Ni, Ag, 14 C, 99 Tc, 239 Pu, 228 Th and 152 Eu. The thermodynamic calculations performed considering repository conditions indicated that the chemistry of most of these elements was dominated by neutral or cationic species, this is the case of 238 Pu 152 Eu, 228 Th, Ni and Ag. The studied gravels presented high sorption capacities for these cationic or neutral species, but they are not efficient on retaining anionic species as in the case of 99 Tc or Sr, which is already present in the composition of the studied gravels. For those elements where the predominant species are carbonated ( 14 C and U) low distribution coefficients were obtained. A preliminary mechanistic sorption model was developed for each radionuclide considering carbonate (>CO 3 H) and calcium hydroxide (>CaOH) sites. Our preliminary model allowed to successfully reproduce the experimental trend of the data obtained in this work., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

We analyzed the antimicrobial resistance (AMR) data of 6519 clinical isolates of Escherichia coli ( n = 3985), Klebsiella pneumoniae ( n = 775), Acinetobacter baumannii ( n = 163), Pseudomonas aeruginosa ( n = 781), Enterococcus faecium ( n = 124), and Staphylococcus aureus ( n = 691) from 43 centers in Mexico. AMR assays were performed using commercial microdilution systems (37/43) and the disk diffusion susceptibility method (6/43). The presence of carbapenemase-encoding genes was assessed using PCR. Data from centers regarding site of care, patient age, and clinical specimen were collected. According to the site of care, the highest AMR was observed in E. coli , K. pneumoniae , and P. aeruginosa isolates from ICU patients. In contrast, in A. baumannii , higher AMR was observed in isolates from hospitalized non-ICU patients. According to age group, the highest AMR was observed in the ≥60 years age group for E. coli , E. faecium , and S. aureus , and in the 19-59 years age group for A. baumannii and P. aeruginosa . According to clinical specimen type, a higher AMR was observed in E. coli , K. pneumoniae , and P. aeruginosa isolates from blood specimens. The most frequently detected carbapenemase-encoding gene in E. coli was bla NDM (84%).