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The sum of products of random variables arises in many applications, particularly in wireless communications. However, the analytical derivation of essential statistics, such as the probability density function and cumulative distribution function, still purveys significant challenges. The objective of this work is to derive exact formulations for the density and distribution of the sum of an arbitrary N instances, each comprising $L_{n}, n\in \{1,2,\ldots ,N\}$ products of independent Rayleigh-distributed variates. This renders our exact formulations rather flexible to comprise different fading scenarios. Based on our findings, we investigate the performance of a communication system employing a reconfigurable intelligent surface (RIS) by deriving key metrics, such as outage probability and average bit error rate. Also, we employ the central limit theorem to approximate the sum of envelope products and performance metrics. In addition, we conduct an asymptotic analysis to deepen our understanding of the system’s performance. Specifically, we obtain simple closed-form expressions for all the metrics derived here. Our analytical results are validated through Monte Carlo simulations.

Objective: To study the suitability of cost-sensitive ordinal artificial intelligence-machine learning (AI-ML) strategies in the prognosis of SARS-CoV-2 pneumonia severity. Materials & methods: Observational, retrospective, longitudinal, cohort study in 4 hospitals in Spain. Information regarding demographic and clinical status was supplemented by socioeconomic data and air pollution exposures. We proposed AI-ML algorithms for ordinal classification via ordinal decomposition and for cost-sensitive learning via resampling techniques. For performance-based model selection, we defined a custom score including per-class sensitivities and asymmetric misprognosis costs. 260 distinct AI-ML models were evaluated via 10 repetitions of 5 × 5 nested cross-validation with hyperparameter tuning. Model selection was followed by the calibration of predicted probabilities. Final overall performance was compared against five well-established clinical severity scores and against a ‘standard’ (non-cost sensitive, non-ordinal) AI-ML baseline. In our best model, we also evaluated its explainability with respect to each of the input variables. Results: The study enrolled $n$ = 1548 patients: 712 experienced low, 238 medium, and 598 high clinical severity. $d$ = 131 variables were collected, becoming $d^\prime$ = 148 features after categorical encoding. Model selection resulted in our best-performing AI-ML pipeline having: 1)no imputation of missing data, 2)no feature selection (i.e. using the full set of $d^\prime$ features), 3)‘Ordered Partitions’ ordinal decomposition, 4)cost-based reimbalance, and 5)a Histogram-based Gradient Boosting classifier. This best model (calibrated) obtained a median accuracy of 68.1% [67.3%, 68.8%] (95% confidence interval), a balanced accuracy of 57.0% [55.6%, 57.9%], and an overall area under the curve (AUC) 0.802 [0.795, 0.808]. In our dataset, it outperformed all five clinical severity scores and the ‘standard’ AI-ML baseline. Discussion & conclusion: We conducted an exhaustive exploration of AI-ML methods designed for both ordinal and cost-sensitive classification, motivated by a real-world application domain (clinical severity prognosis) in which these topics arise naturally. Our model with the best classification performance exploited successfully the ordering information of ground truth classes, coping with imbalance and asymmetric costs. However, these ordinal and cost-sensitive aspects are seldom explored in the literature.

The fluctuating two-ray (FTR) fading model has proven to effectively characterize small-scale fading in gigahertz and terahertz frequency bands. In these wireless scenarios, one can enhance the system performance by exploiting multiple communication links, where sums of random variables (RVs) commonly arise and, therefore, need to be statistically addressed to evaluate the system behavior. Unfortunately, the statistical analysis of such sums is rather challenging, which has motivated further research to find exact solutions. In this article, we characterize the exact statistics of sums of independent and identically distributed squared FTR RVs. Specifically, we derive novel improved expressions for the probability density function (PDF) and the cumulative distribution function (CDF). Our expressions demonstrated to be lighter, faster, and more manageable than the state-of-the-art solutions. More importantly, we show that the sum PDF and the sum CDF can be written as a random mixture of not necessarily identically distributed gamma PDFs and CDFs, respectively. Capitalizing on our findings, we assess the performance of multi-branch maximal-ratio combining receivers operating over FTR fading channels, considering three essential metrics: average bit-error rate, outage probability, and ergodic capacity. Simulation results confirm the validity and efficiency of our analytical derivations.

Sparse code multiple access (SCMA) is an interesting proposal for supporting massive machine-type communications (mMTC) in future mobile networks. In this use case, mobile networks connect to Internet of Things (IoT) devices, which may have low computational processing capacities, and thus, they are exposed to different security threats. In this regard, physical-layer security (PLS) arises as an alternative technique to protect information. This work proposes a new scheme based on the design of unknown codebooks to an external eavesdropper aiming at guaranteeing PLS in the uplink of SCMA systems over generalized $\kappa$-$\mu$ fading channels. Considering that the SCMA codebook design can be realized from the rotation of base quadrature-amplitude modulation (QAM) constellations using the signal-space-diversity (SSD) technique, a novel upper-bound expression to calculate the average bit error probability (ABEP) of multidimensional SSD systems is derived. Then, a metric to select the best rotation matrices is determined. With this, a set of optimal and suboptimal rotation matrices can be acquired. A strategy to obtain secret keys in the SCMA system is presented by considering imperfect channel estimation. The secret keys are used to select matrices for rotating the base QAM constellations used in the codebooks generation. Finally, an uncoded and turbo-encoded SCMA system is evaluated using Monte Carlo simulations. The results show that our proposal ensures a near-optimal SCMA performance while the eavesdropper cannot decode the information.

Introduction: Obesity is a known risk factor for urinary incontinence (UI). As bariatric surgery can result in significant and sustainable weight loss, many chronic diseases closely linked to obesity have likewise shown improvement after surgical weight loss. We propose that bariatric surgery may significantly improve obesity-related UI symptoms as well as improve quality of life. Methods and procedures: This is an interim analysis of an ongoing, prospective, single-institution observational study looking at UI in women enrolled in a bariatric surgery program. Participants completed the Pelvic Floor Distress Inventory (PFDI-20), International Consultation on Incontinence Questionnaire—Urinary Incontinence Short Form (ICIQ-UI-SF), King’s Health Questionnaire (KHQ), and Patient Global Impression of Improvement (PGI-I). Questionnaires were administered upon enrollment, pre-operatively, and at 3, 6, and 12 months post-operatively. Demographic data were collected at each interval and analyzed with descriptive statistics. Results: At analysis, 108 patients had enrolled in the study and 60% had progressed to surgery. We analyzed the following surveys: enrollment (n= 108), pre-operative (n= 43), 3-month (n= 29), 6-month (n= 26), and 1-year (n= 27). Mean BMI decreased from 49.8 to 31.1 at 1-year. All surveys showed significant improvement in UI symptoms over time. Overall, UI symptoms (PDFI-20) are correlated with BMI at time of survey and %TBWL (p= 0.03, p= 0.019). Additionally, perception of symptom improvement with surgery (PGI-I) improved over time (3-month p= 0.0289, 6-month p= 0.0024, 12-month p= 0.0035). Quality of life related to UI symptoms (KHQ) significantly improved after surgery (p= 0.0047 3-month, p= 0.0042 6-month, p= 0.0165 1-year). Conclusions: Although the relationship is complex and likely depends on many factors, weight loss after bariatric surgery is associated with improvement in UI symptoms and UI-related quality of life. Bariatric surgery can play a role in the long-term treatment of UI in women with obesity that may negate the need for further invasive UI procedures. Graphical abstract:

Introduction: Secondary hyperparathyroidism (SHPT) after bariatric surgery has significant adverse implications for bone metabolism, increasing the risk for osteoporosis and fracture. Our aim was to characterize prevalence and identify risk factors for SHPT in bariatric surgery patients. Methods: We performed a single-institution, retrospective chart review of patients who underwent bariatric surgery from June 2017 through December 2021. Demographic and clinical data were collected, including serum parathyroid hormone, calcium, and vitamin D3 at enrollment and 3, 6, and 12-months postoperatively. Chi-square or Fisher’s exact tests were used to analyze categorical data and Mann–Whitney Utest for continuous data. Multivariable analysis using binomial logistic regression assessed risk factors for SHPT. P-values ≤ 0.05 were considered significant. Results: 350 patients were analyzed. SHPT prevalence at any time point was 72.9%. 65.8% had SHPT at enrollment; 45.9% resolved with intensive vitamin supplementation; and 19.7% had recurrent SHPT. New-onset SHPT occurred in 8.6%. Persistent SHPT was present in 42.4% at 1-year. Baseline SHPT correlated with black race and T2DM. SHPT at any time point correlated with T2DM and higher baseline BMI. 1-year SHPT correlated with RYGB, depression, and longer time in program. SHPT was not correlated with %TBWL at any time point. In patients with SHPT, vitamin D3 deficiency prevalence was significantly higher at baseline (77.0%) compared to all post-bariatric time points (16.7%, 17.3%, and 23.1%; P< 0.0001). Conclusions: SHPT is highly prevalent in patients with obesity seeking weight loss surgery. 42% had persistent SHPT at 1-year despite appropriate vitamin supplementation. Current vitamin D3 and calcium supplementation protocols may not effectively prevent SHPT in many post-bariatric patients. Low prevalence of concomitant vitamin D3 deficiency with SHPT after bariatric surgery suggests that there may be alternative mechanisms in this population. Further studies are needed to develop effective treatment strategies to mitigate the adverse effects of bariatric surgery on bone metabolism.

The sum of random variables (RVs) appears extensively in wireless communications, at large, both conventional and advanced, and has been subject of longstanding research. The statistical characterization of the referred sum is crucial to determine the performance of such communications systems. Although efforts have been undertaken to unveil these sum statistics, e.g., probability density function (PDF) and cumulative distribution function (CDF), no general efficient nor manageable solutions capable of evaluating the exact sum PDF and CDF are available to date. The only formulations are given in terms of either the multi-fold Brennan’s integral or the multivariate Fox $H$ -function. Unfortunately, these methods are only feasible up to a certain number of RVs, meaning that when the number of RVs in the sum increases, the computation of the sum PDF and CDF is subject to stability problems, convergence issues, or inaccurate results. In this paper, we derive new, simple, exact formulations for the PDF and CDF of the sum of $L$ independent and identically distributed $\alpha $ - $\mu $ RVs. Unlike the available solutions, the computational complexity of our analytical expressions is independent of the number of summands. Capitalizing on our unprecedented findings, we analyze, in exact and asymptotic manners, the performance of $L$ -branch pre-detection equal-gain combining and maximal-ratio combining receivers over $\alpha $ - $\mu $ fading environments. The coding and diversity gains of the system for both receivers are analyzed and quantified. Moreover, numerical simulations show that the computation time reduces drastically when using our expressions, which are arguably the most efficient and manageable formulations derived so far.

Elucidating how different fertilization treatments affect the resilience of farming systems and the environmental adaptability of agricultural crops is relevant to assess their efficacy as a strategy for minimizing yield fluctuations and supporting global food security. The aim of this work was to compare the effects of fertilization practices and to distinguish the effect of macronutrients on the resilience of maize, wheat, and soybean cropping systems. A long‐term experiment involving the three crops and five fertilization treatments (control without fertilization, nitrogen and sulphur fertilization, phosphorus and sulfur fertilization, nitrogen and phosphorus fertilization, nitrogen, phosphorus and sulfur fertilization) was conducted for 19 years in the Pampean region (Argentina) that includes five study sites. The four combinations of nutrient additions increased crop yields in unfavorable environments, which indicates that even in adverse years, fertilization was a valid tool to sustain yield performance. The Finlay and Wilkinson regression slopes in maize and full‐season soybean did not differ between fertilization treatments, which suggests that fertilization did not change crop adaptation to the environment and that the observed positive effect of fertilization in unfavorable environments was maintained along the environmental gradient. In contrast, wheat and double‐cropped soybean were able to capitalize on the environmental conditions of favorable years, as shown by the progressive increases in yields as the environment became more favorable. Maize had the highest response to nitrogen, whereas wheat and double‐cropped soybean exhibited the highest responses to phosphorus and sulfur, respectively. Our findings are useful to extract guidelines that may lead to greater resilience through fertilization management practices. Crop yield resilience was studied for five contrasting fertilization treatments over 19 years on five sites.All fertilization treatments raised maize, wheat, and soybean yields in unfavorable environments.These benefits were maintained along the environmental gradient in maize and full‐season soybean.Fertilization helped wheat and double‐cropped soybean to capitalize favorable environments.

ABSTRACTIn recent years, the issue of memorable tourism experience (MTE) has garnered increasing attention from scholars and tourism practitioners. This paper provides a systematic review of 52 articles on MTE listed on the SCOPUS and WOS databases from 2012 to 2020. Qualitative analysis of the literature identified nine main categories of topics in MTE-related articles. Results showed that the largest proportion of articles focused on how MTEs influenced tourists’ perceptions and behaviours and how they shaped destination marketing. Co-occurrence analysis was performed to investigate trends in the keywords used by academics over the past five years. The geographic location of studies, research methods and theories applied in these articles were also analysed. Most articles were published in the current decade and China was the geographic setting for the highest number of articles in the review. The review concludes with the theoretical and practical implications of the study as well as the directions for future research.

Purpose: This study aims to provide a case example of two partner institutions and business faculty who creatively used a collaborative online international learning (COIL) experience during the height of the COVID-19 pandemic and transition to online learning to internationalize an undergraduate business class and use existing technology to offer a case study project to further students’ global mindset. Design/methodology/approach: Using open-ended qualitative comments from an American college and a Peruvian university, researchers uncovered key themes from a virtual COIL-based learning experience offered as part of an international business class. Findings: Student end-of-course evaluation comments from both countries validated the success of the learning experience and value of working together with other students and faculty in a virtual setting. Research limitations/implications: Areas for future research are provided to extend these initial exploratory findings. However, the implications are clear that the methodology is also appropriate in nonpandemic situations and can quickly bring a global mindset to remote corners of the globe and ensure all students experience the “virtual” study abroad, even when there are travel limitations or budget restrictions for students or the institutions. Practical implications: The implementation detail provided can be easily replicated by other institutions with a global mindset and internationalization goals. Social implications: The proliferation of COIL-based experiences will impact how study abroad experiences are defined and offered in the future. Originality/value: While researchers have documented COIL experiences in the academic literature, their use during the COVID-19 pandemic, as often the only solution for on-going internationalization, has not been thoroughly studied or documented. In addition, the class activities further used team-based international workplace pedagogy, authentic engagement and technology.

Sums of random variables are the statistical core in several performance analyses of communications systems. In this letter, we provide a fundamental contribution to this field, deriving original, exact, handy expressions for the probability density function and the cumulative distribution function for the sum of independent and identically distributed $\kappa - \mu $ variates. Our formulations can be quickly computed in all cases, even in those for which Brennan’s integral—the only available exact approach—may take several hours or not compute at all. For application purposes, we use our formulations to investigate the outage probability and the mean bit error rate in equal-gain diversity systems. Further contribution includes asymptotic analyses. Numerical simulations validate our findings.

This article addresses a new way of generating compliant trajectories for control using movement primitives to allow physical human–robot interaction where parallel robots (PRs) are involved. PRs are suitable for tasks requiring precision and performance because of their robust behavior. However, two fundamental issues must be resolved to ensure safe operation: first, the force exerted on the human must be controlled and limited, and second, Type II singularities should be avoided to keep complete control of the robot. We offer a unified solution under the dynamic movement primitives (DMP) framework to tackle both tasks simultaneously. DMPs are used to get an abstract representation for movement generation and are involved in broad areas, such as imitation learning and movement recognition. For force control, we design an admittance controller intrinsically defined within the DMP structure, and subsequently, the Type II singularity evasion layer is added to the system. Both the admittance controller and the evader exploit the dynamic behavior of the DMP and its properties related to invariance and temporal coupling, and the whole system is deployed in a real PR meant for knee rehabilitation. The results show the capability of the system to perform safe rehabilitation exercises.

This article proposes a new method for estimating the extrinsic calibration parameters between any pair of multibeam LiDAR sensors on a vehicle. Unlike many state-of-the-art works, this method does not use any calibration pattern or reflective marks placed in the environment to perform the calibration; in addition, the sensors do not need to have overlapping fields of view. An iterative closest point (ICP)-based process is used to determine the values of the calibration parameters, resulting in better convergence and improved accuracy. Furthermore, a setup based on the car learning to act (CARLA) simulator is introduced to evaluate the approach, enabling quantitative assessment with ground-truth data. The results show an accuracy comparable with other approaches that require more complex procedures and have a more restricted range of applicable setups. This work also provides qualitative results on a real setup, where the alignment between the different point clouds can be visually checked. The open-source code is available at https://github.com/midemig/pcd_calib.

ABSTRACTThis phenomenological study explored the ways women served as validating agents for Latino men who had transferred from a community college to a four-year institution. Informed by Rendón’s theory of validation, participants expressed numerous ways in which women figures (e.g., mothers, sisters, significant others) were sources of validation across their pre and post transfer experience. Findings yielded the need for increased involvement of women in men of color initiatives, compensation for emotional labor performed by women, and engagement opportunities for women family members. The authors provide recommendations for research and practice.

This study examines Venezuelan subsidiaries of multinational enterprises, analysing how companies adapt and survive in adverse business environments. Despite the prolonged, persistent Venezuelan crisis, there are multinationals that remain operational while facing government intervention threats, rampant inflation, currency shortages, and unfavourable labour laws. Using a case study approach, four subsidiaries are explored through face-to-face and telephone interviews with company managers, each representing distinct economic activities and business sectors. We found companies surviving the Venezuelan crisis developed new adaptation capabilities, including the ability to shorten the existing power distance, substitute limited resources, retain key talent, and obtain alternate funding sources. Understanding how these adaptation capabilities allow firms to operate in crisis provides valuable insights for managers and academicians and advances crisis management literature. Practical implications and areas for future research are discussed.

Sums of Weibull variates arise in several communications fields, such as optical, mobile, and radar systems. However, due to the intricate task of evaluating the Weibull sums, only a few works deal with the exact sum statistics. Some of these works provide solutions in terms of nested infinite sums-products, approximate solutions, or in terms of especial functions that, unfortunately, have not yet been implemented in mathematical packages such as Maple, MATLAB, or Mathematica. Yet, these solutions are time-consuming and prone to convergence and instability problems as the number of Weibull summands increases. In this letter, based on a comprehensive calculus of residues, we derive novel exact expressions for the probability density function and the cumulative distribution function of the sum of independent and identically distributed Weibull random variables. Numerical results show that our derived solutions are faster and enjoy a lower computational burden than the state-of-the-art ones.

Fully conjugated macrocycles containing benzenoid rings rarely show global aromaticity/antiaromaticity. Herein, we report an annulene-like macrocycle CBTTand its S,S-dioxidized macrocycle DOCBTTwith alternative quinoidal thiophene/1,1-dioxide thiophene and triphenyl amine moieties. They both showed temperature-dependent intramolecular dynamics and global antiaromatic character with 32π electrons at low temperature. However, CBTTand DOCBTThave different conjugated pathways.

Nitrogen deficiency can severely limit sunflower (Helianthus annuusL.) grain yield and quality. Our objective was to evaluate N diagnosis methods based on: (a) pre‐plant soil nitrate‐nitrogen (NO3––N) test (PPSNT) and soil N mineralized in short‐term anaerobic incubation (Nan), (b) Greenness index (GI) and the normalized difference vegetation index (NDVI) measured at 6 (V6) and 12 (V12) leaves, and (c) grain nitrogen concentration (Nc). Seventeen experiments were carried out between 2010 and 2019 in Argentina, evaluating nine N rates (0, 30, 40, 60, 80, 90, 120, 150, and 160 kg N ha–1). The GI, NDVI, N sufficiency index and relative normalized difference vegetation index (NDVIr) were determined at V6and V12growth stages. On average, yield response to N was 492 kg ha–1and Ncresponse was 0.25% in 9 and 11 responsive experiments, respectively. The inclusion of Nan improved the PPSNT diagnosis method. The critical N availability (PPSNT + fertilizer N) threshold was 115 kg N ha–1for experiments with low Nan (<60 mg kg–1), and 90 kg N ha–1for experiments with high Nan (>60 mg kg–1). The NDVIr at V12allowed monitoring the crop N status with a 0.95 critical threshold. The Ncadequately diagnosed N deficiencies and the critical threshold was 2.26%. Also, Ncwas predicted from the ratio between N availability and grain yield (R2 = .39). Our results would allow to better estimate N availability to recommend adequate N fertilizer rates for sunflower aiming to optimize grain yield and quality, and minimize the economic and environmental cost of fertilization. Aim: evaluate N diagnosis methods for grain yield and quality of sunflower.Nitrogen mineralized in anaerobic incubation improved the pre‐plant soil NO3––N test.The relative Green Seeker at V12growth stage was associated with relative yield.Grain N concentration diagnosed N availability in sunflower.The N availability to grain yield ratio defined the N rate required.

Evaluar el grado de seguimiento de las recomendaciones de las versiones de la Guía española para el manejo del asma(GEMA 2009 y 2015) y su repercusión en el control de la enfermedad.

School-based targeted preventive chemotherapy (PC), the primary strategy for soil-transmitted helminth (STH) control, typically focusing on primary schoolchildren, was expanded to secondary school students in the Philippines in 2016. This program still excludes adults, who may also suffer from considerable morbidity and can be a significant reservoir of infection. Mass drug administration (MDA), where the entire population is treated, would bring additional health benefits but will also increase implementation costs. The incremental cost of implementing MDA for STH control compared to expanded school-based targeted PC, however, is unknown.

The purpose of this research is to use the SWOT analysis to examine Peru's country conditions and identify areas for potential sources of entrepreneurial opportunities. Findings indicate Peru's main drivers of its economic activities are the energy, agriculture and tourism industries. However, insufficient infrastructure, crime, corruption, poor education and poverty limit economic development. Opportunities for entrepreneurship exist through a diversified economy with a favourable business environment. Although current entrepreneurial activity is mostly concentrated in the retail, hotel and restaurant sector, there is potential to increase entrepreneurial activity within the main economic activities as foreign investments are expected to increase Peru's export-driven industries. Because Peru's government efforts to support entrepreneurship and entrepreneurship education have been stagnant in the last decade, we offer recommendations for policy makers to increase entrepreneurial activities based on training and motivation to improve business conditions that would promote and encourage entrepreneurial behaviour.

Purpose: Estimation of brain deformation is crucial during neurosurgery. Whilst mechanical characterisation captures stress–strain relationships of tissue, biomechanical models are limited by experimental conditions. This results in variability reported in the literature. The aim of this work was to demonstrate a generative model of strain energy density functions can estimate the elastic properties of tissue using observed brain deformation. Methods: For the generative model a Gaussian Process regression learns elastic potentials from 73 manuscripts. We evaluate the use of neo-Hookean, Mooney–Rivlin and 1-term Ogden meta-models to guarantee stability. Single and multiple tissue experiments validate the ability of our generative model to estimate tissue properties on a synthetic brain model and in eight temporal lobe resection cases where deformation is observed between pre- and post-operative images. Results: Estimated parameters on a synthetic model are close to the known reference with a root-mean-square error (RMSE) of 0.1 mm and 0.2 mm between surface nodes for single and multiple tissue experiments. In clinical cases, we were able to recover brain deformation from pre- to post-operative images reducing RMSE of differences from 1.37 to 1.08 mm on the ventricle surface and from 5.89 to 4.84 mm on the resection cavity surface. Conclusion: Our generative model can capture uncertainties related to mechanical characterisation of tissue. When fitting samples from elastography and linear studies, all meta-models performed similarly. The Ogden meta-model performed the best on hyperelastic studies. We were able to predict elastic parameters in a reference model on a synthetic phantom. However, deformation observed in clinical cases is only partly explained using our generative model.

Circadian rhythms align physiological functions with the light–dark cycle through oscillatory changes in the abundance of proteins in the clock transcriptional programme. Timely removal of these proteins by different proteolytic systems is essential to circadian strength and adaptability. Here we show a functional interplay between the circadian clock and chaperone-mediated autophagy (CMA), whereby CMA contributes to the rhythmic removal of clock machinery proteins (selective chronophagy) and to the circadian remodelling of a subset of the cellular proteome. Disruption of this autophagic pathway in vivo leads to temporal shifts and amplitude changes of the clock-dependent transcriptional waves and fragmented circadian patterns, resembling those in sleep disorders and ageing. Conversely, loss of the circadian clock abolishes the rhythmicity of CMA, leading to pronounced changes in the CMA-dependent cellular proteome. Disruption of this circadian clock/CMA axis may be responsible for both pathways malfunctioning in ageing and for the subsequently pronounced proteostasis defect.

The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection.

Agricultural management practices such as fertilization may affect the overall soil quality and nutrient supply capacity. In this study, we hypothesized that long‐term fertilization promotes (a) an increase in the proportion of easily degradable soil organic C, N, and S fractions and (b) changes in the soil C, N, and S stoichiometric ratios in the direction of favoring the specific nutrient added to the soil. We included S in our study due to the increasing importance of S fertilization in many agricultural soils. A long‐term experiment involving six fertilization treatments and maize (Zea maysL.), soybean [Glycine max(L.) Merr.], and wheat (Triticum aestivumL.) as cash crops was conducted for 14 yr in an on‐farm network located in the Pampean region (Argentina). Long‐term fertilization did not have a central role in defining the C, N, and S distribution between soil organic fractions or their stoichiometric ratios since the particulate organic matter (POM)‐C/total C, POM‐S/total S, C/N, C/N, and N/S ratios were not affected by fertilization treatments and the mineralizable N/total N ratio varied in a very short range. Instead, long‐term fertilization increased residue C inputs to the soil (8.7–19 Mg ha−1over the unfertilized control) and, in turn, increases in soil total C, N, and S followed a linear relationship with residue inputs. This relationship was not affected by fertilization or site factors. These data contribute to understanding of the effects of continued fertilization on soil properties such as the distribution of fast‐ and slow‐cycling organic matter and nutrient concentrations, which are essential for effectively managing soils for sustainable agriculture.

The paper develops a mixed logistic financial distress prediction model with two independent random coefficients and validates it for public Argentinean companies. This study complements existing literature on bankruptcy prediction in emerging economies advancing the application of contemporary econometric methods (Caro et al., 2013). Anticipating bankruptcy risks increases portfolios' profitability. Emerging economies and frontier markets differ from developed economies in political, cultural, social and institutional terms. Given those differences, investors and lenders need specific bankruptcy and financial distress prediction models. The model developed achieves an excellent performance using financial statements from firms listed in the Buenos Aires Stock Exchange during 1993-2000 with ratios accepted in the literature (Altman, 1993; Jones and Hensher, 2004). Results show that profitability, assets turnover and cash flow from operations reduce the likelihood of financial distress while leverage increases it for companies operating in a frontier market such as Argentina.

This study evaluated whether plasma miRNAs were specifically associated with sudden cardiac and/or arrhythmic death (SCD) in a cohort of patients with coronary heart disease (CHD), most of whom were without primary prevention implantable cardioverter-defibrillators.

ABSTRACTBuilding fair, equitable, and beneficial partnerships between institutions collaborating in research in low- and middle-income countries (LMIC) and high-income countries (HIC) has become an integral part of research capacity building in global health in recent years. In this paper, we offer an example of an academic collaboration between the University of California Los Angeles, Center for Health Policy and Research (UCLA CHPR) and the University of Philippines, Manila, College of Public Health (UPM CPH) that sought to build an equitable partnership between research institutions. The partnership was built on a project to build capacity for research and produce data for policy action for the prevention and care of non-communicable diseases (NCDs) through primary healthcare in the Philippines. The specific objectives of the project were to: (1) locally adapt the Primary Care Assessment Tool for the Philippines and use the adapted tool to measure facility-level primary care delivery, (2) conduct focus group discussions (FGDs) to gather qualitative observations regarding primary care readiness and capacity, and (3) conduct a comprehensive population-based health survey among adults on NCDs and prior healthcare experience. We describe here the progression of the partnership between these institutions to carry out the project and the elements that helped build a stronger connection between the institutions, such as mutual goal setting, cultural bridging, collaborative teams, and capacity building. This example, which can be used as a model depicting new directionality and opportunities for LMIC-HIC academic partnerships, was written based on the review of shared project documents, including study protocols, and written and oral communications with the project team members, including the primary investigators. The innovation of this partnership includes: LMIC-initiated project need identification, LMIC-based funding allocation, a capacity-building role of the HIC institution, and the expansion of scope through jointly offered courses on global health.

Background: Dengue remains a major public health problem in the Philippines, particularly in urban areas of the National Capital Region. Thematic mapping using geographic information systems complemented by spatial analysis such as cluster analysis and hot spot detection can provide useful information to guide preventive measures and control strategies against dengue. Hence, this study was aimed to describe the spatiotemporal distribution of dengue incidence and identify dengue hot spots by barangayusing reported cases from Quezon City, the Philippines from 2010 to 2017. Methods: Reported dengue case data at barangaylevel from January 1, 2010 to December 31, 2017 were obtained from the Quezon City Epidemiology and Surveillance Unit. The annual incidence rate of dengue from 2010 to 2017, expressed as the total number of dengue cases per 10,000 population in each year, was calculated for each barangay. Thematic mapping, global cluster analysis, and hot spot analysis were performed using ArcGIS 10.3.1. Results: The number of reported dengue cases and their spatial distribution varied highly between years. Local clusters were evident during the study period. Eighteen barangayswere identified as hot spots. Conclusions: Considering the spatial heterogeneity and instability of hot spots in Quezon City across years, efforts towards the containment of dengue can be made more targeted, and efficient with the application of hot spot analysis in routine surveillance. This may be useful not only for the control of dengue but also for other diseases, and for public health planning, monitoring, and evaluation.

ABSTRACTA growing body of research focusing on male students of color has provided insights for educators to better understand the academic challenges that impact their success. However, minimal attention has centered on the essential needs that influence their daily experiences in college. This qualitative study explored the experiences of male students of color in community college. Findings revealed various environmental challenges experienced by these men, including food and housing insecurities. Implications for institutional responsibility are extended.

Proteotoxic stress such as heat shock causes heat-shock factor (HSF)-dependent transcriptional upregulation of chaperones. Heat shock also leads to a rapid and reversible downregulation of many genes, a process we term stress-induced transcriptional attenuation (SITA). The mechanism underlying this conserved phenomenon is unknown. Here we report that enhanced recruitment of negative transcription elongation factors to gene promoters in human cell lines induces SITA. A chemical inhibitor screen showed that active translation and protein ubiquitination are required for the response. We further find that proteins translated during heat shock are subjected to ubiquitination and that p38 kinase signaling connects cytosolic translation with gene downregulation. Notably, brain samples of subjects with Huntington’s disease also show transcriptional attenuation, which is recapitulated in cellular models of protein aggregation similar to heat shock. Thus our work identifies an HSF-independent mechanism that links nascent-protein ubiquitination to transcriptional downregulation during heat shock, with potential ramifications in neurodegenerative diseases.

Surface manifestations of earthquake fault rupture are strongly affected by the dilatant response of the soil deposit overlying the bedrock fault displacement. The granular material’s in-situ void ratio and effective confining stress affect its dilatancy, and hence, its stress-strain response and ductility. Distinct element method (DEM) assemblages of 3D, non-spherical particles are prepared with different void ratio distributions, and their dilatancy is characterized using direct shear test simulations. DEM simulations capture the response of sand in centrifuge experiments of earthquake fault rupture propagation. Macro-scale mechanisms of ground deformation and micro-scale mechanisms of shear band formation during dip-slip fault rupture propagation are analyzed through particle rotations, homogenized strains, frictional dissipation, and particle displacements. The brittle and ductile responses of granular media undergoing fault rupture are related to changes in the coordination numbers in each particle assemblage. The deformational characteristics of a metastable fabric in the loosest particle assemblages and a stable fabric in the densest particle assemblages are revealed through the accumulation of energy dissipated through friction. The normalized strong contact forces are also greater in magnitude in the loosest particle assemblages and greater in number in the densest assemblages.

Soybean has grown to be the major crop both in terms of land use and grain production in Brazil. In turn, soybean leads all crops in nutrient consumption. Fields growing high-yielding cultivars are capable of supporting grain yields that are twice the country's average, leading to questions about how these yields impact crop nutrient demand. Uptake patterns find N and K in highest demand, with K having the fastest acquisition rate (63% of total K uptake occurs before pod filling). Remobilization from leaves, stems, and petioles provides a significant contribution to the total grain content of N, P, K, S, Cu, and Zn, while Mg, B, and Fe only remobilize from leaves. [ABSTRACT FROM AUTHOR]