bluuebunny/crossref_metadata_2025 huggingface dataset:
Fishmeal substitution by zooplankton or Daphnia magna biomass meals in the diet of Nile tilapia: Effects on growth, gut histological changes, bacterial abundance and stress tolerance
Authors: El‐feky Mohamed M. M. , Abo‐Taleb Hamdy A. , Alsqufi Ahmed Saud , Mansour Abdallah Tageldein , Mabrouk Mohamed M. , Abdelzaher Othman F. , Ashour Mohamed , Elokaby Mohamed A. , Sallam Ahmed E.
Published: May 2024

Fishmeal substitution with sustainable feed sources is highly essential towards sustainable production. This study aimed to investigate the effects of substituting fishmeal (FM) with Daphnia magna biomass meal (DBM) or zooplankton biomass meal (ZBM) on growth performance, liver and intestinal histology, gut bacterial abundance and stress tolerance of Nile tilapia, Oreochromis niloticus, fry. Nile tilapia fry (0.23 ± 0.04 g) were randomly assigned to five groups of three replicates. The control diet comprised 300 g/kg FM, and the FM was substituted with DBM or ZBM at levels of 25% and 50% (DBM‐25, DBM‐50, ZBM‐25 and ZBM‐50 respectively) in the other experimental diets. The experiment lasted 56 days in 1.5 m3 concrete tanks. The results revealed that weight gain and feed conversion ratio (FCR) significantly (p ≤ 0.035 and 0.025 respectively) improved with a polynomial response with a peak at 25% ZBM and a linear increase with DBM up to 50% of FM. Histometric indices of the distal intestine showed improvements (p ≤ 0.001) in villus height, villus width, crypt depth and muscle thickness of fish fed DBM or ZBM compared to the control. In the meantime, there were no histological abnormalities in the liver sections. The replacement of FM with DBM or ZBM could modulated gut bacterial abundance, including total bacterial count, Escherichia coli, Bacillus subtilis, and Lactobacillus sp. The fish‐fed DBM or ZBM‐containing diets had higher (p ≤ 0.05) tolerances to salinity stress than the control group. In conclusion, DBM or ZBM could replace FM up to 50% and 25%, respectively with improved fish growth performance, FCR, gut histology and tolerance to salinity stress.
Effects of essential oils on heat‐stressed poultry: A review
Authors: Yilmaz Emre , Gul Mehmet
Published: May 2024

While certain animal species are sensitive to heat stress, poultry particularly modern breeds, are more susceptible to high ambient temperatures. This has major implications for the poultry industry, as heat stress causes large financial losses. These economic losses will probably increase as a consequence of a predicted rise in global temperatures. Heat stress adversely affects various aspects of poultry, including physiological responses, growth and production performance, meat quality, egg quality, and reproductive activities. These effects occur through specific molecular and metabolic pathways. To mitigate the impacts of heat stress, it is crucial to go beyond administrative practices and implement dietary interventions during high ambient temperature. Such interventions aim to optimize the development of stressed bird species in terms of performance, health, and profitability. Essential oils have shown promising in mitigating the negative effects of heat stress and improved antioxidant status, growth and yield performance, as well as meat and egg quality in poultry. They actively participate in certain metabolic and molecular pathways that help to counteract the effects of heat stress. The article discusses the impacts of essential oil supplementation on the relationships between antioxidant enzyme activity, these molecular, and metabolic pathways, as well as various parameters such as growth and yield performance, and product quality heat‐stressed poultry.
The relationship of health activation with risk of future cardiovascular disease among rural family caregivers of patients with chronic illnesses
Authors: Lin Chin‐Yen , Chung Misook L. , Wu Jia‐Rong , Smith Jennifer L. , Latimer Abigail , Kang JungHee , Thompson Jessica H. , Rayens Mary Kay , Feltner Frances J. , Biddle Martha J. , Lennie Terry A. , Moser Debra K.
Published: May 2024

Background

Family caregivers are at higher risk for developing cardiovascular disease (CVD) than non‐caregivers. This risk is worse for those who live in rural compared to urban areas. Health activation, an indicator of engagement in self‐care, is predictive of health outcomes and CVD risk in several populations. However, it is not known whether health activation is associated with CVD risk in rural caregivers of patients with chronic illnesses nor is it clear whether sex moderates any association.

Objectives

Our aims were to determine (1) whether health activation independently predicts 10‐year CVD risk; and (2) whether sex interacts with health activation in the prediction of 10‐year CVD risk among rural family caregivers (N = 247) of patients with chronic illnesses.

Methods

Health activation was measured using the Patient Activation Measure. The predicted 10‐year risk of CVD was assessed using the Framingham Risk Score. Data were analyzed using nonlinear regression analysis.

Results

Higher levels of health activation were significantly associated with decreased risk of developing CVD (p < 0.028). There was no interaction of sex with health activation on future CVD risk. However, male caregivers had greater risk of developing CVD in the next 10 years than female caregivers (p < 0.001).

Conclusions

We demonstrated the importance of health activation to future CVD risk in rural family caregivers of patients with chronic illnesses. We also demonstrated that despite the higher risk of future CVD among male, the degree of association between health activation and CVD risk did not differ by sex.
Rituximab is a safe and effective alternative treatment for patients with autoimmune hepatitis: Results from the ColHai registry
Authors: Riveiro‐Barciela Mar , Barreira‐Díaz Ana , Esteban Paula , Rota Rosa , Álvarez‐Navascúes Carmen , Pérez‐Medrano Indhira , Mateos Beatriz , Gómez Elena , De‐la‐Cruz Gema , Ferre‐Aracil Carlos , Horta Diana , Díaz‐González Álvaro , Ampuero Javier , Díaz‐Fontenla Fernando , Salcedo Magdalena , Ruiz‐Cobo Juan‐Carlos , Londoño María‐Carlota
Published: May 2024

Background and Aims

Small series suggest that rituximab could be effective as treatment for autoimmune hepatitis (AIH), although data are scarce. We aimed to evaluate the efficacy and safety of rituximab in different cohorts of patients with AIH.

Methods

Multicentre retrospective analysis of the 35 patients with AIH and its variant forms treated with rituximab and included in the ColHai registry between 2015 and 2023.

Results

Most patients were female (83%), 10 (29%) had cirrhosis and four (11.4%) variant forms of AIH. Indication for rituximab were as follows: 14(40%) refractory AIH, 19(54%) concomitant autoimmune or haematological disorder, 2(6%) intolerance to prior treatments. In three (9%) subjects with a concomitant disorder, rituximab was the first therapy for AIH. Overall, 31 (89%) patients achieved or maintained complete biochemical response (CBR), including the three in first‐line therapy. No difference in CBR was observed according to rituximab indication (refractory AIH 86% vs. concomitant disorders 90%, p = .824) or cirrhosis (80% vs. 92%, p = .319). Rituximab was associated with a significant reduction in corticosteroids (median dose: prior 20 vs. post 5 mg, p < .001) and the discontinuation of ≥1 immunosuppressant in 47% of patients. Flare‐free rate at 1st, 2nd and 3rd year was 86%, 73% and 62% respectively. Flares were not associated with the development of liver failure and were successfully managed with repeated doses of rituximab and/or increased corticosteroids. Three (9%) patients experienced infusion‐related adverse events (1 anaphylaxis and 2 flu‐like symptoms) and five (14%) infections.

Conclusion

Rituximab is safe and effective in patients with refractory AIH and those treated due to concomitant autoimmune or haematological disorders.
A systematic literature review investigating the association between biodiversity and beaver lodges
Authors: Wilson Jude Banks , Bremner‐Harrison Samantha
Published: May 2024

The positive relationship between biodiversity and beaver‐modified habitats such as ponds, dams, and canals has been demonstrated; however, the association between biodiversity and beaver lodges is rarely investigated. Due to increasing habitat fragmentation, there is a growing need to identify local biodiversity hotspots.

This systematic review assessed current scientific knowledge concerning the association between beaver lodges and biodiversity. Specifically, the study aimed to 1) investigate the evidence for beaver lodges being local biodiversity hotspots; 2) identify areas of future research centred around the relationship between biodiversity and beaver lodges; and 3) provide recommendations on how to monitor the relationship between biodiversity and beaver lodges within the UK.

Through a stepwise process of database searching and literature sorting, a final dataset of 35 articles emerged, with each article including at least one species, besides beavers, interacting with beaver lodges.

Analysis of the final dataset of articles showed beaver lodges offer multiple uses and fitness benefits for several species in highly seasonal environments, with daily and seasonal visitor variation influenced by intraspecific and interspecific interactions. Beaver lodges were shown to have higher species richness and diversity compared to microhabitats in the surrounding areas, supporting the concept of beaver lodges being local biodiversity hotspots.

We recommend that future studies use videographic methodology to monitor beaver lodges and other treatment groups in the surrounding area. Using the described methodology, beaver management plans should monitor beaver lodges across the northern hemisphere, helping to further understand these important local biodiversity hotspots.
Genomic basis of adaptation to climate and parasite prevalence and the importance of odorant perception in the ant Temnothorax longispinosus
Authors: Macit Maide Nesibe , Collin Erwann , Pfenninger Markus , Foitzik Susanne , Feldmeyer Barbara
Published: May 2024

A co‐evolutionary arms race ensues when parasites exhibit exploitative behaviour, which prompts adaptations in their hosts, in turn triggering counter‐adaptations by the parasites. To unravel the genomic basis of this coevolution from the host's perspective, we collected ants of the host species Temnothorax longispinosus, parasitized by the social parasite Temnothorax americanus, from 10 populations in the northeastern United States exhibiting varying levels of parasite prevalence and living under different climatic conditions. We conducted a genome‐wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with both prevalence and climate. Our investigation highlighted a multitude of candidate SNPs associated with parasite prevalence, particularly in genes responsible for sensory perception of smell including odorant receptor genes. We further focused on population‐specific compositions of cuticular hydrocarbons, a complex trait important for signalling, communication and protection against desiccation. The relative abundances of n‐alkanes were correlated with climate, while there was only a trend between parasite prevalence and the relative abundances of known recognition cues. Furthermore, we identified candidate genes likely involved in the synthesis and recognition of specific hydrocarbons. In addition, we analysed the population‐level gene expression in the antennae, the primary organ for odorant reception, and established a strong correlation with parasite prevalence. Our comprehensive study highlights the intricate genomic patterns forged by the interplay of diverse selection factors and how these are manifested in the expression of various phenotypes.
Leadless pacemaker implementation at the right atrial appendage apex: An initial preclinical assessment
Authors: Lin Yu‐Sheng , Wu Lung‐Sheng , Ho Wan‐Chun , Lai Chao‐Sung , Su Wilber , Chu Pao‐Hsien
Published: May 2024

Objective

This study evaluates the feasibility and efficacy of implanting a leadless pacemaker at the right atrial appendage (RAA) in a preclinical minipig model, aiming to address the limitations of atrial pacing with current leadless devices like the Medtronic Micra, which is typically used for right ventricular implantation.

Methods

Four minipigs, each with a median body weight of 45.8 ± 10.0 kg, underwent placement of the Micra transcatheter pacing system (TPS) via the right femoral vein into the RAA apex. The pacing performance was assessed over 1‐week (short‐term) and 3‐month (long‐term) periods.

Outcomes

The initial findings indicated successful implantation, with satisfactory intrinsic R‐wave amplitudes and pacing threshold. In the following period, the sensitivity, threshold, and impedance were stable with time. Notably, upon explanation at 3 months, a deep myocardial penetration by the device was observed, necessitating a redesign for safe long‐term use in a growing subject's heart.

Conclusion

While initial results suggest that RAA apex placement of the Micra TPS is promising for potential inclusion in a dual‐chamber pacing system, the issue of myocardial penetration highlights the need for device redesign to ensure safety and effectiveness in long‐term applications.
Wake Up Safe in the USA & International Patient Safety
Authors: Iyer Rajeev S. , Dave Nandini , Du Trung , Bong Choon Looi , Siow Yew Nam , Taylor Elsa , Tjia Imelda
Published: May 2024

Patient safety is the most important aspect of anesthetic care. For both healthcare professionals and patients, the ideal would be no significant morbidity or mortality under anesthesia. Lessons from harm during healthcare can be shared to reduce harm and to increase safety. Many nations and individual institutions have developed robust safety systems to improve the quality and safety of patient care. Large registries that collect rare events, analyze them, and share findings have been developed. The approach, the funding, the included population, support from institutions and government and the methods of each vary. Wake Up Safe (WUS) is a patient safety organization accredited by Agency for Healthcare Research and Quality. Wake Up Safe was established in the United States in 2008 by the Society for Pediatric Anesthesia. The initiative aims to gather data on adverse events, analyze these incidents to gain insights, and apply this knowledge to ultimately reduce their occurrence. The purpose of this review is to describe the patient safety approaches in the USA. Through a national patient safety database WUS. Similar approaches either through WUS international or independent safety approaches have been described in Australia‐New Zealand, India, and Singapore. We examine the patient safety processes across the four countries, evaluating their incident review process and the distribution of acquired knowledge. Our focus is on assessing the potential benefits of a WUS collaboration, identifying existing barriers, and determining how such a collaboration would integrate with current incident review databases or systems.
The association between perceived injustice and political trust: Testing a dual‐pathway model through anger and patriotism across four countries
Authors: Moon Chanki , Travaglino Giovanni A.
Published: May 2024

While past research has found an association between perceived political injustice and diminished trust in institutions, the pathways connecting these constructs remain underexplored. In this study, we proposed a sequential indirect‐effect model, from perceived injustice to feelings of disrespect and ultimately lower trust, via the dual pathways of anger against institutions and constructive patriotism. We tested our model using samples from four countries, namely South Korea, Italy, the United Kingdom, and the United States (NTotal = 2502). Results revealed a simple indirect effect of injustice via perceived personal respect. Additionally, two sequential indirect pathways emerged via anger and constructive patriotism. Specifically, individuals with higher levels of perceived personal injustice were less likely to trust institutions through decreased perceived personal respect. Moreover, perceived personal respect was associated with reduced trust via increased anger and decreased constructive patriotism. While the results were largely consistent across countries, the significance and relative strength of some of the paths exhibited variability. The findings offer insights into the psychological underpinnings of political trust across contexts. Limitations, implications of the results, and avenues for future research are discussed.
Can exports be pain relievers? The effect of exports on workplace safety and health
Authors: Li Ling , Liang Yang
Published: May 2024

This study examines the effect of exports on worker safety and health in the US. We use foreign countries' unilateral liberalization as an instrument to capture the demand shocks on US exports. Our two‐stage estimates with establishment fixed effects suggest that a $1000 increase in exports per worker decreased the workplace injury rate by a significant 0.7%, which implies an annual reduction of about 55,000 injuries among manufacturing workers. The reduction in injuries is more salient among establishments with lower injury rates, indicating an increase of inequality in working conditions. The improvement in working conditions might come from more investment in advanced equipment and better compliance with safety and health regulations.
Evaluation and comparison of the efficacy and safety of the combination of topical phenytoin and microneedling with microneedling alone in the treatment of atrophic acne scars: A controlled blinded randomized clinical trial
Authors: Sadeghzadeh‐Bazargan Afsaneh , Pashaei Arezoo , Ghassemi Mohammadreza , Dehghani Abbas , Shafiei Mojtaba , Goodarzi Azadeh
Published: May 2024

Introduction

Severe acne breakouts often lead to atrophic acne scars, which affect millions of people worldwide and can significantly affect a person's self‐confidence and self‐image. Given the difficulty in treating atrophic acne scars, this study aims to investigate the efficacy of topical phenytoin in the treatment of atrophic acne scars.

Method

This split face clinical trial on 25 patients between the ages of 18 and 40 involved the application of microneedling on one side of the face, with three sessions taking place over the course of a month. On the other side, a 1% phenytoin cream was administered three times daily for 1 week following the microneedling procedure. Baseline information was collected for all patients, and follow‐up assessments were conducted during the treatment sessions and 2 months after the last session. The assessments included evaluating the number and area of pores and spots, determining scar severity, assessing patient satisfaction, and recording any potential complications.

Results

Among patients, 20 individuals (80%) were females, and the average age of the participants was 35.96 ± 9.23. In terms of the fine pore area, despite the fine pore count, both groups showed improvement over time (p: 0.03 vs. 0.06). Also, regarding large pore count and area, and the count and area of spots, both groups showed improvement over time (p: 0.001). However, there were no significant differences between the two groups (p > 0.05). On the other hand, when it comes to acne scar grade and patients' satisfaction, the phenytoin group outperformed the control group in all follow‐up sessions and this difference was found to be significant (p: 0.001). It is worth noting that no complications were observed among any of the patients.

Conclusion

It appears that combining phenytoin cream with microneedling has a more effective therapeutic outcome in enhancing atrophic acne scars, when compared to microneedling alone, and this method can be regarded as a viable alternative in treating these types of scars.
Infrastructure Bottlenecks as Opportunity for Local Development: The Case of Decentralized Green‐Hydrogen Projects
Authors: Walker Benedikt , Klagge Britta
Published: May 2024

Energy geography has not scrutinized the role of energy infrastructures and market design for decentralized energy production and local development. The paper addresses this research gap by looking at the emerging green‐hydrogen market in Germany. We argue, first, that the capacity and geography of infrastructures and associated bottlenecks determine how supply and demand can be matched at different scales. Second, market design and associated controversies over infrastructure bottlenecks are important for understanding the green‐hydrogen market and its geography and financing. Conceptually, we draw on the geography‐of‐markets literature. Empirically, we show how infrastructure bottlenecks and market design link the green‐hydrogen to the renewable‐electricity market. As long as the market design requires green‐hydrogen production in geographical and temporal correlation with renewable‐electricity generation, the geography of green‐hydrogen production follows the geography of renewable‐electricity generation. Moreover, bottlenecks in transportation infrastructures offer a window of opportunity for decentralized production and local development.
Organ donation and HIV: Awareness and willingness to be a living donor among people with HIV in Uganda
Authors: Bongomin Felix , Nantale Ritah , Kibone Winnie , Awekonimungu Byron , Oyoo Nixson , Okello James , Muzoora Conrad , Hamer Davidson H.
Published: May 2024

Background

HIV+‐to‐HIV+ organ transplantation has demonstrated promise and is now authorized for research purposes in certain countries. However, organ transplantation is dependent on the availability of organ donors. We assessed the awareness and willingness to donate organs among people with HIV (PWH) in Uganda.

Methods

We conducted a multicenter cross‐sectional study between October 2023 and January 2024 in four large HIV clinics in Northern Uganda. The study population consisted of PWH. A structured questionnaire was used to collect data regarding awareness, willingness, and beliefs regarding organ donation. Organ donation was defined as the willingness to be a living donor of a solid organ. We conducted multivariable logistic regression to assess for an association between willingness to donate organs and selected exposures. Data were analyzed in Stata version 15.0. Results are expressed as adjusted odds ratio (AOR) with 95% confidence intervals (CI).

Results

A total of 232 participants were recruited. The mean age ± standard deviation of the participants was 42.2±11.8 years. All participants were on antiretroviral therapy. Sixty‐two (26.7%) had a CD4 count less than or equal to 200 cells/mm3. The majority (80.6%, n = 187) had ever heard of organ donation. Slightly more than a third (34.9%, n = 81) were willing to donate organs. Factors associated with willingness to be a living organ donor included being female (AOR: 1.56; 95% CI: 1.15−2.11), having a tertiary education level (AOR: 1.79; 95% CI: 1.03−3.11), average monthly income >500 000 UGX (135.1USD) (AOR: 5.5; 95% CI: 1.97−15.40), ever heard about organ donation (AOR: 5.4; 95% CI: 1.67−17.8), and attending an organ donation campaign (AOR: 2.0; 95% CI: 1.07−3.74).

Conclusions

Awareness about organ donation was high but the willingness to be a living organ donor was low among PWH in Uganda. There is a need to sensitize the community about the need and benefits of organ donation with the involvement of media and the healthcare workers.

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Algebraic fibre spaces with strictly nef relative anti‐log canonical divisor
Authors: Liu Jie , Ou Wenhao , Wang Juanyong , Yang Xiaokui , Zhong Guolei
Published: May 2024

Let be a projective klt pair, and a fibration to a smooth projective variety with strictly nef relative anti‐log canonical divisor . We prove that is a locally trivial fibration with rationally connected fibres, and the base is a canonically polarized hyperbolic manifold. In particular, when is a single point, we establish that is rationally connected. Moreover, when and is strictly nef, we prove that is ample, which confirms the singular version of a conjecture by Campana and Peternell for threefolds.
Underwater Acoustic Non-Reciprocal Manipulation Based on Dynamic-Modulation Structures
Authors: Wen Zhuoqun , Yuan Jinbo , Huang Yu , Zhou Xiaoming
Published: May 2024

Underwater acoustic non-reciprocal transmission via dynamic-modulation structures with time-varying mass and stiffness is studied. The model system consists of spatiotemporally modulated discrete lattices immersed in the water background. Based on the transfer matrix method, an analytic model for the coupled continuum-discrete system is developed to calculate acoustic scattering responses in the frequency domain. Finite-difference time-domain computation is conducted for the coupled system to verify the theoretical model. Results show that acoustic non-reciprocal transmission in opposite directions appears at frequencies where there are asymmetric bandgaps in dispersion diagrams. Asymmetric transmission can be enhanced in magnitude by engineering the modulating amplitudes of time-varying parameters or increasing the number of lattice elements, while the frequency bandwidth can be broadened by cascading structural elements with different modulating frequencies due to the gap-combining effect. The model may find potential applications in underwater acoustic isolation and sonar communication.
Designing the Geometry of Compact Tension Specimens for Easy Fracture Toughness Measurement Using Reinforcement Learning
Authors: Qiu Cheng , Lin Yuxia , Shen Yan , Song Hongwei , Yang Jinglei
Published: May 2024

For composite laminates, a rising R-curve is observed for their fracture toughness under Mode I stress, which is important for a comprehensive failure analysis of the materials. Since it is laborious to measure the R-curve due to its dependence on both the load and the crack extension, we put forward a novel compact tension specimen by modifying its geometry to eliminate the relation between fracture toughness and crack extension, so as to simplify the experimental process of the R-curve measurement by only recording the load history. Two machine-learning models were developed for the optimum sample design based on the finite element analysis of the effect of sample geometries on the R-curve. A simple neural network model was built for designing tapered specimen and a reinforcement learning model was created for further finding the best design from a broader design space. The results showed that, in contrast to the specimens with a tapered shape, which only ensure the independence between the R-curve and crack extension in the case of a small extension, the design provided by the reinforcement learning provides such independence across a wider range of crack length and an improved accuracy.
The diagnostic value of ultrasound in the assessment of soft tissue masses in rheumatology practice – a case series of 4 patients
Authors: Sapundzhieva Tanya , Todorov Plamen , Sapundzhiev Lyubomir , Pazardzhikliev Dimitar , Klinkanov Kamen , Batalov Anastas
Published: May 2024

A great number of studies have proved the added value of musculoskeletal ultrasound (MSUS) in the diagnosis, assessment of disease activity and treatment response in both inflammatory and degenerative rheumatic diseases. However, it is a frequent scenario that rheumatologists should also assess patients with various soft tissue masses, referred to their practices. In such cases, MSUS could be a valuable and precise tool that helps in the evaluation and triage of these lesions. Hereafter, we describe a case series, where MSUS played a decisive role in the diagnostic process and allowed for prompt patients’ management.
An explicit granular-mechanics approach to marine sediment acoustics
Authors: Clark Abram H. , Olson Derek R. , Swartz Andrew J. , Starnes W. Mason
Published: May 2024

Here, we theoretically and computationally study the frequency dependence of phase speed and attenuation for marine sediments from the perspective of granular mechanics. We leverage recent theoretical insights from the granular physics community as well as discrete-element method simulations, where the granular material is treated as a packing of discrete objects that interact via pairwise forces. These pairwise forces include both repulsive contact forces as well as dissipative terms, which may include losses from the fluid as well as losses from inelasticity at grain–grain contacts. We show that the structure of disordered granular packings leads to anomalous scaling laws for frequency-dependent phase speed and attenuation that do not follow from a continuum treatment. Our results demonstrate that granular packing structure, which is not explicitly considered in existing models, may play a crucial role in a complete theory of sediment acoustics. While this simple approach does not explicitly treat sound propagation or inertial effects in the interstitial fluid, it provides a starting point for future models that include these and other more complex features.
Interfacial rheology of polyelectrolyte microgel monolayers: Correlation between mechanical properties and phase behavior at oil-water interfaces
Authors: Schmidt Maximilian M. , Laukkanen Olli-Ville , Bochenek Steffen , Schier W. Sebastian , Richtering Walter
Published: May 2024

Microgels are confined to fluid interfaces in numerous applications, yet many aspects of the microgel-covered interface remain unclear. In this work, we use interfacial shear and dilatational rheology to study the effects of electrostatics on the mechanical characteristics of polyelectrolyte microgel monolayers at oil-water interfaces as a function of the microgel interfacial concentration. We find a clear correlation between the influence of charges on the mechanical properties of the monolayers and the influence of charges on their two-dimensional phase behavior. At lower microgel interfacial concentrations, the moduli of uncharged monolayers are larger than those of charged monolayers. Consistent with our previous findings on the phase behavior, here, the mechanical response of the interfacial layer is controlled by in-plane interactions of the microgels within the interface. At higher microgel interfacial concentrations, the moduli of charged monolayers are larger than those of uncharged monolayers. The mechanical response becomes dominated by out-of-plane interactions between the fractions of the adsorbed microgels further from the interface. Evidently, electrostatic interactions do not contribute directly to the mechanical response of the interfacial layer, that is, through charge repulsion, but indirectly through the difference in the swelling properties of uncharged and charged microgels. These results advance our understanding of how the charge-dependent microstructure of the interfacial layer affects its mechanical properties, which is not only important from a fundamental point of view but is also relevant to applications where polyelectrolyte microgels are used as responsive emulsion stabilizers.
Integration policies shape ethnic-racial majorities’ threat reactions to increasing diversity
Authors: Kende Judit , Jacobs Dirk , Green Eva G. T. , Tropp Linda R. , Huo Yuen J. , Dovidio John F. , Jiménez Tomás R. , Schildkraut Deborah J. , Klein Olivier
Published: May 2024

Increasing ethnic and racial diversity often fuels feelings of threat among ethnic-racial majorities (e.g., self-identified white Americans and European nationals). We contend that these threat perceptions depend on the policy context. Across four studies, we test whether more inclusive immigrant integration policies attenuate ethnic-racial majorities’ threat reactions. Studies 1 to 3 (
n
= 469, 733, and 1745, respectively) used experimental methods with white American participants in the United States. Study 4 (
n
= 499,075) used secondary analysis of survey data comparing attitudes of nationals in 30 European countries and measured the impact of actual changes in diversity and policies over 10 years. Our results show that integration policies shape threat reactions even in those situations when increasing diversity could be seen as the most threatening: when narratives highlight the majority’s impending minority position or when diversity suddenly increases. When policies are more inclusive toward immigrants, ethnic-racial majority participants report less threat (or no threat) in response to increasing diversity.
Subgenomic flavivirus RNA as key target for live-attenuated vaccine development
Authors: Doets Kristel , Pijlman Gorben P.
Published: May 2024

Live-attenuated flavivirus vaccines confer long-term protection against disease, but the design of attenuated flaviviruses does not follow a general approach. The non-coding, subgenomic flavivirus RNA (sfRNA) is produced by all flaviviruses and is an essential factor in viral pathogenesis and transmission. We argue that modulating sfRNA expression is a promising, universal strategy to finetune flavivirus attenuation for developing effective flavivirus vaccines of the future.
Temporal gene expression during asexual development of the apicomplexan
Sarcocystis neurona
Authors: Dangoudoubiyam Sriveny , Norris Jamie K. , Namasivayam Sivaranjani , de Paula Baptista Rodrigo , Cannes do Nascimento Naila , Camp Joseph , Schardl Christopher L. , Kissinger Jessica C. , Howe Daniel K.
Published: May 2024

Asexual replication in the apicomplexan
Sarcocystis neurona
involves two main developmental stages: the motile extracellular merozoite and the sessile intracellular schizont. Merozoites invade host cells and transform into schizonts that undergo replication via endopolygeny to form multiple (64) daughter merozoites that are invasive to new host cells. Given that the capabilities of the merozoite vary significantly from the schizont, the patterns of transcript levels throughout the asexual lifecycle were determined and compared in this study. RNA-Seq data were generated from extracellular merozoites and four intracellular schizont development time points. Of the 6,938 genes annotated in the
S. neurona
genome, 6,784 were identified in the transcriptome. Of these, 4,111 genes exhibited significant differential expression between the merozoite and at least one schizont development time point. Transcript levels were significantly higher for 2,338 genes in the merozoite and 1,773 genes in the schizont stages. Included in this list were genes encoding the secretory pathogenesis determinants (SPDs), which encompass the surface antigen and SAG-related sequence (SAG/SRS) and the secretory organelle proteins of the invasive zoite stage (micronemes, rhoptries, and dense granules). As anticipated, many of the
S. neurona
SPD gene transcripts were abundant in merozoites. However, several SPD transcripts were elevated in intracellular schizonts, suggesting roles unrelated to host cell invasion and the initial establishment of the intracellular niche. The hypothetical genes that are potentially unique to the genus
Sarcocystis
are of particular interest. Their conserved expression patterns are instructive for future investigations into the possible functions of these putative
Sarcocystis
-unique genes.

IMPORTANCE

The genus
Sarcocystis
is an expansive clade within the Apicomplexa, with the species
S. neurona
being an important cause of neurological disease in horses. Research to decipher the biology of
S. neurona
and its host-pathogen interactions can be enhanced by gene expression data. This study has identified conserved apicomplexan orthologs in
S. neurona
, putative
Sarcocystis
-unique genes, and gene transcripts abundant in the merozoite and schizont stages. Importantly, we have identified distinct clusters of genes with transcript levels peaking during different intracellular schizont development time points, reflecting active gene expression changes across endopolygeny. Each cluster also has subsets of transcripts with unknown functions, and investigation of these seemingly
Sarcocystis
-unique transcripts will provide insights into the interesting biology of this parasite genus.
Different sampling strategies for optimal detection of the overall genetic diversity of methicillin-resistant
Staphylococcus aureus
Authors: Zohar Cretnik Tjasa , Maric Leon , Rupnik Maja , Janezic Sandra
Published: May 2024

Surveillance schemes for methicillin-resistant
Staphylococcus aureus
(MRSA) are widely established at the national and international levels. Due to the simple standardization of the protocol, mainly isolates from bloodstream infections are used. However, the limitations of this simple surveillance system are well described. We conducted a comprehensive analysis of MRSA isolates in a large Slovenian region over 5 years to identify the optimal sample group for assessing the overall MRSA diversity. At the same time, this study provides to date non-available molecular characterization of Slovenian MRSA isolates. A total of 306 MRSA isolates from various sources were sequenced and phenotypically tested for resistance. The isolates exhibited significant molecular diversity, encompassing 30 multi locus sequence type (MLST) sequence types (STs), 39 ST-SCC
mec
genetic lineages, 49
spa
types, and 29 antibiotic resistance profiles. Furthermore, the isolate pool comprised 57 resistance genes, representing 22 resistance mechanisms, and 96 virulence genes. While bloodstream isolates, commonly used in surveillance, provided insights into frequently detected clones, they overlooked majority of clones and important virulence and resistance genes. Blood culture isolates detected 21.3%
spa
types, 24.1% resistance phenotypes, and 28.2% MLST-SCC
mec
profiles. In contrast, strains from soft tissues demonstrated superior genomic diversity capture, with 65.3%
spa
types, 58.6% resistance phenotypes, and 71.8% MLST-SCC
mec
profiles. These strains also encompassed 100.0% of virulence and 82.5% of resistance genes, making them better candidates for inclusion in surveillance programs. This study highlights the limitations of relying solely on bloodstream isolates in MRSA surveillance and suggests incorporating strains from soft tissues to obtain a more comprehensive understanding of the epidemiology of MRSA.

IMPORTANCE

In this study, we investigated the diversity of methicillin-resistant
Staphylococcus aureus
(MRSA), a bacterium that can cause infections that are difficult to treat due to its resistance to antimicrobial agents. Currently, surveillance programs for MRSA mainly rely on isolates from bloodstream infections, employing a standardized protocol. However, this study highlights the limitations of this approach and introduces a more comprehensive method. The main goal was to determine which group of samples is best suited to understand the overall diversity of MRSA and to provide, for the first time, molecular characterization of Slovenian MRSA isolates. Our results suggest that including MRSA strains from soft tissue infections rather than just blood infections provides a more accurate and comprehensive view of bacterial diversity and characteristics. This insight is valuable for improving the effectiveness of surveillance programs and for developing strategies to better manage MRSA infections.
Extended-spectrum beta-lactamase-producing
Escherichia coli
and
Klebsiella pneumoniae
: insights from a tertiary hospital in Southern Thailand
Authors: Romyasamit Chonticha , Sornsenee Phoomjai , Kawila Soontara , Saengsuwan Phanvasri
Published: May 2024

Broad-spectrum ampicillin-resistant and third-generation cephalosporin-resistant Enterobacteriaceae, particularly
Escherichia coli
and
Klebsiella pneumoniae
that have pathological features in humans, have become a global concern. This study aimed to investigate the prevalence, antimicrobial susceptibility, and molecular genetic features of extended-spectrum beta-lactamase (ESBL)-producing
E. coli
and
K. pneumoniae
isolates in Southern Thailand. Between January and August 2021, samples (
n
= 199) were collected from a tertiary care hospital in Southern Thailand. ESBL and AmpC-lactamase genes were identified using multiplex polymerase chain reaction (PCR). The genetic relationship between ESBL-producing
E. coli
and
K. pneumoniae
was determined using the enterobacterial repetitive intergenic consensus (ERIC) polymerase chain reaction. ESBL-producing
E. coli
and
K. pneumoniae
isolates were mostly collected from catheter urine samples of infected female patients. The ESBL production prevalence was highest in the medical wards (
n
= 75, 37.7%), followed by that in surgical wards (
n
= 64, 32.2%) and operating rooms (
n
= 19, 9.5%). Antimicrobial susceptibility analysis revealed that all isolates were resistant to ampicillin, cefotaxime, ceftazidime, ceftriaxone, and cefuroxime; 79.4% were resistant to ciprofloxacin; and 64.3% were resistant to trimethoprim-sulfamethoxazole. In ESBL-producing
K. pneumoniae
and
E. coli
,
bla
TEM
(
n
= 57, 72.2%) and
bla
CTX-M
(
n
= 61, 50.8%) genes were prominent; however, no
bla
VEB
,
bla
GES
, or
bla
PER
were found in any of these isolates. Furthermore, only ESBL-producing
K. pneumoniae
had co-harbored
bla
TEM
and
bla
SHV
genes at 11.6%. The ERIC-PCR pattern of multidrug-resistant ESBL-producing strains demonstrated that the isolates were clonally related (95%). Notably, the presence of multidrug-resistant and extremely resistant ESBL producers was 83.4% and 16.6%, respectively. This study highlights the presence of
bla
TEM
,
bla
CTX-M
, and co-harbored genes in ESBL-producing bacterial isolates from hospitalized patients, which are associated with considerable resistance to beta-lactamase and third-generation cephalosporins.

IMPORTANCE

We advocate for evidence-based guidelines and antimicrobial stewardship programs to encourage rational and appropriate antibiotic use, ultimately reducing the selection pressure for drug-resistant bacteria and lowering the likelihood of ESBL-producing bacterial infections.
Mutation of
hmgA
, encoding homogentisate 1,2-dioxygenase, is responsible for pyomelanin production but does not impact the virulence of
Burkholderia cenocepacia
in a chronic granulomatous disease mouse lung infection
Authors: Moustafa Dina A. , Wu Linda , Ivey Melissa , Fankhauser Sarah C. , Goldberg Joanna B.
Published: May 2024

The
Burkholderia cepacia
complex (Bcc) is a group of Gram-negative opportunistic bacteria often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis (CF) and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals; pigment production has been reported to enable Bcc strains to overcome the host cell oxidative burst. In this work, we investigated the role of pyomelanin in resistance to oxidative stress and virulence in strains J2315 and K56-2, two epidemic CF isolates belonging to the
Burkholderia cenocepacia
ET-12 lineage. We previously reported that a single amino acid change from glycine to arginine at residue 378 in homogentisate 1,2-dioxygenase (HmgA) affects the pigment production phenotype: pigmented J2315 has an arginine at position 378, while non-pigmented K56-2 has a glycine at this position. Herein, we performed allelic exchange to generate isogenic non-pigmented and pigmented strains of J2315 and K56-2, respectively, and tested these to determine whether pyomelanin contributes to the protection against oxidative stress
in vitro
as well as in a respiratory infection in CGD mice
in vivo
. Our results indicate that the altered pigment phenotype does not significantly impact these strains’ ability to resist oxidative stress with H
2
O
2
and NO
in vitro
and did not change the virulence and infection outcome in CGD mice
in vivo
suggesting that other factors besides pyomelanin are contributing to the pathophysiology of these strains.

IMPORTANCE

The
Burkholderia cepacia
complex (Bcc) is a group of Gram-negative opportunistic bacteria that are often associated with fatal pulmonary infections in patients with impaired immunity, particularly those with cystic fibrosis and chronic granulomatous disease (CGD). Some Bcc strains are known to naturally produce pyomelanin, a brown melanin-like pigment known for scavenging free radicals and overcoming the host cell oxidative burst. We investigated the role of pyomelanin in
Burkholderia cenocepacia
strains J2315 (pigmented) and K56-2 (non-pigmented) and performed allelic exchange to generate isogenic non-pigmented and pigmented strains, respectively. Our results indicate that the altered pigment phenotype does not significantly impact these strains’ ability to resist H
2
O
2
or NO
in vitro
and did not alter the outcome of a respiratory infection in CGD mice
in vivo
. These results suggest that pyomelanin may not always constitute a virulence factor and suggest that other features are contributing to the pathophysiology of these strains.
Provenance history of the eastern Pearl River Mouth Basin: Implications for the evolution of the South China margin
Authors: Li Yichao , Gong Chenglin , Qiu Xinwei , Breitfeld H. Tim , Barbarand Jocelyn , Colin Christophe
Published: May 2024

The provenance history of the Pearl River Mouth Basin is of great significance for understanding how the South China margin evolved from a Mesozoic Andean-type subduction margin into the present-day rifted passive margin. However, the long-term provenance history of continental margin basins in the northern South China Sea is poorly understood. Newly identified Mesozoic–Cenozoic successions from the Lufeng Sag in the eastern Pearl River Mouth Basin provide valuable records of the provenance history and related evolution of the South China margin. Here, we trace the provenance of the eastern Pearl River Mouth Basin using U-Pb ages of zircon and ZTR values (proportions of zircon, tourmaline, and rutile in all transparent heavy minerals) of heavy minerals, and determine the tectonic setting and crustal thickness using trace element ratios and Eu anomalies in zircon. The results show that from the middle Eocene strata—which have a U-Pb age spectrum similar to strata of the Upper Cretaceous—to the Miocene strata, the proportion of Mesozoic age populations gradually increases, while the proportion of Paleozoic age populations decreases. In addition, following the middle Eocene high values, the ZTR values decreased during the late Eocene and then increased during the early Oligocene. Based on the variations in zircon age populations and ZTR values, the middle Eocene sediment is interpreted to have been recycled from Upper Cretaceous to middle Eocene successions, followed by an early Oligocene provenance change from intrabasinal to extrabasinal sources. Moreover, the zircon trace element ratios and Eu anomalies indicate that a widespread Mesozoic continental magmatic arc formed before ca. 90 Ma along the South China margin, and the crust simultaneously thickened during this time. In accordance with the provenance history, the evolution of the South China margin is divided into three tectonic phases: the Paleo-Pacific, Proto-South China Sea, and South China Sea. During the transition from the Paleo-Pacific to the Proto-South China Sea tectonic phase, sediment was recycled from Upper Cretaceous to middle Eocene successions in the eastern Pearl River Mouth Basin. During the transition from the Proto-South China Sea to the South China Sea tectonic phases, the provenance changed from intrabasinal to extrabasinal sources.