bluuebunny/crossref_metadata_2025 huggingface dataset:
Resource gaps pose the greatest threat for bumblebees during the colony establishment phase
Authors: Becher Matthias A. , Twiston‐Davies Grace , Osborne Juliet L. , Lander Tonya A.
Published: March 2024

A common management intervention to support declining wild pollinators is ‘pollinator planting’. However, despite years of inclusion in conservation initiatives, global pollinator declines continue.

Using the agent‐based model BEE‐STEWARD with two example species, Bombus terrestris (L. 1758) and B. pascuorum (Scopoli, 1763) (Hymenoptera: Apidae), we explore when during the year bumblebee resource demand is the highest and how that relates to seasonal changes in colony composition (numbers of eggs, larvae, pupae and adults). We then examine the impact of two‐week periods of resource scarcity across the year. Finally, we explore how enhancement with early spring‐blooming herbaceous species or trees changes colony survival and queen production.

In the United Kingdom, there is a previously under‐appreciated ‘hungry gap’ for bumblebees in March–April, before the peak flight period, driven by the demands of larvae for protein and thermoregulation in the colony, rather than the number of adult bees.

A 2‐week gap in forage availability during this period drives a 50%–87% drop in the production of daughter queens. Adding early‐blooming species in the model had significant, positive, long‐term effects on colony survival probability and daughter queen production.

Pollinator‐planting initiatives in both national and international conservation schemes need to include plants that flower up to 1 month before the adults of target social pollinator species are apparent in the field, during the period that larvae dominate the colony. This approach is likely to increase colony survival and queen production, contributing towards halting and reversing global pollinator decline.
The lack of either IRF9, or STAT2, has surprisingly little effect on human natural killer cell development and function
Authors: Calvo‐Apalategi Ane , Nevado Marta López , Bravo‐Gallego Luz Yadira , González‐Granado Luis Ignacio , Allende Luis M. , Pena Rebeca Rodríguez , López‐Granados Eduardo , Reyburn Hugh T.
Published: March 2024

Analysis of genetically defined immunodeficient patients allows study of the effect of the absence of specific proteins on human immune function in real‐world conditions. Here we have addressed the importance of type I interferon signalling for human NK cell development by studying the phenotype and function of circulating NK cells isolated from patients suffering primary immunodeficiency disease due to mutation of either the human interferon regulatory factor 9 (IRF9) or the signal transducer and activator of transcription 2 (STAT2) genes. IRF9, together with phosphorylated STAT1 and STAT2, form a heterotrimer called interferon stimulated gene factor 3 (ISGF3) which promotes the expression of hundreds of IFN‐stimulated genes that mediate antiviral function triggered by exposure to type I interferons. IRF9‐ and STAT2‐deficient patients are unable to respond efficiently to stimulation by type I interferons and so our experiments provide insights into the importance of type I interferon signalling and the consequences of its impairment on human NK cell biology. Surprisingly, the NK cells of these patients display essentially normal phenotype and function.
A new strategy for immunotherapy of microsatellite‐stable (MSS)‐type advanced colorectal cancer: Multi‐pathway combination therapy with PD‐1/PD‐L1 inhibitors
Authors: Cai Lingli , Chen Anqi , Tang Dong
Published: March 2024

Colorectal cancer (CRC) is a frequent gastrointestinal malignancy with high rates of morbidity and mortality; 85% of these tumours are proficient mismatch repair (pMMR)‐microsatellite instability‐low (MSI‐L)/microsatellite stable (MSS) CRC known as ‘cold’ tumours that are resistant to immunosuppressive drugs. Monotherapy with programmed death 1 (PD‐1)/programmed death ligand 1 (PD‐L1) inhibitors is ineffective for treating MSS CRC, making immunotherapy for MSS CRC a bottleneck. Recent studies have found that the multi‐pathway regimens combined with PD‐1/PD‐L1 inhibitors can enhance the efficacy of anti‐PD‐1/PD‐L1 in MSS CRC by increasing the number of CD8+ T cells, upregulating PD‐L1 expression and improving the tumour microenvironment. This paper reviews the research progress of PD‐1/PD‐L1 inhibitors in combination with cytotoxic T‐lymphocyte–associated antigen 4 (CTLA‐4) inhibitors, oncolytic virus, intestinal flora, antiangiogenic agents, chemotherapy, radiotherapy and epigenetic drugs for the treatment of pMMR‐MSI‐L/MSS CRC.
The mean–variance (in)efficiency of duration‐based immunization
Authors: François Pascal , Moraux Franck
Published: March 2024

Empirical studies report inconclusive assessment of duration‐based immunization, notably showing that more sophisticated strategies do not outperform immunization relying on Macaulay duration. This article provides a mean–variance framework to explain this puzzle. We characterize the efficient portfolio allocations for a stylized barbell strategy trading off reinvestment risk with discounting risk. We show, in a model‐free setting, that barbell allocations form a convex set in the mean–variance space, and the endpoints of the efficient frontier can switch as time passes, reversing the set of efficient allocations. Consequently, duration‐based immunization, which is not minimum variance, can exhibit temporary inefficiency. This result is numerically illustrated in a one‐factor Gaussian and a two‐factor non‐Gaussian model. Using yield curve scenarios resampled from U.S. data over the 1977–2020 period, we further corroborate our conclusions non‐parametrically, and find that duration‐based immunization is sometimes inefficient.
Out‐of‐pocket expenditure among patients with diabetic foot ulcer in a tertiary care hospital of south India: A cross‐sectional study
Authors: Seshadri Hariharan , Karthikeyan Venkatesh , Rudrakumar Malavika , Seshadri Prashanth , Vasudevan Damodaran , Ranganathan Vasuki , Dave Tirth , Ghosh Victor , Ramsai Vadada , Kamaraj Balakrishnan
Published: March 2024

Diabetic foot ulcer is a debilitating complication of long‐standing diabetes mellitus. Patients lose their earning potential, face repeated hospitalizations, and are forced to bear heavy treatment costs. This places an enormous financial burden on the patients and their families. This study seeks to ascertain the out‐of‐pocket expenditure among these patients and correlate it with their risk factor profile. In this hospital‐based cross‐sectional study, a total of 154 patients with diabetic foot ulcers or amputations have been studied with an elaborate patient questionnaire and relevant clinical examinations. The costs incurred and the risk factors of the patients were analyzed for statistical association. The median total annual out‐of‐pocket expenditure for the management of diabetic foot ulcers among the study participants was found to be ₹29 775 (₹9650–₹81 120) ($378.14 [$122.56–$1030.22]). Out of the total expenditure, 58.49% went towards direct medical costs, 5.64% towards direct non‐medical costs, and 35.88% for indirect costs. Medications, ulcer dressing and periodic debridement have accounted for 79.26% of direct medical costs. Transportation (61.37%) and patient's loss of income (89.45%) account for the major costs under the direct non‐medical and indirect cost categories, respectively. A high ulcer grade and area, long ulcer duration, and past history of ulcers have higher expenditure. Patients seeking treatment from private establishments and those engaged in professional/skilled occupations have higher expenses. Adequate dressing of foot ulcers and proper footwear are associated with lower treatment expenditure. 68.8% of the participants have faced catastrophic expenditure due to treatment costs of diabetic foot ulcers. Adequate glycaemic control and proper foot care are necessary. Patients must seek medical care at the earliest in case of foot ulceration. Clinicians must provide proper wound care, institute effective antibiotics, and manage the complications. Government and insurance schemes are required to alleviate the patients' financial burden.
Racial/ethnic disparities in sleep health among adolescents in South Korea: The role of substance use behaviours
Authors: Jeon Bomin , Chung Sophia J. , Lee Young Ji
Published: March 2024

Aim

To examine the relationship between racial/ethnic disparities and substance use behaviours (alcohol and tobacco use) and their impact on the sleep health of South Korean adolescents.

Design

Secondary analysis of cross‐sectional study data from the 2021 Korea Youth Risk Behaviour Web‐based Survey dataset.

Methods

Given that Korean society has historically linked its racial/ethnic identity to a shared bloodline, we categorized 2644 adolescents from the Korea Youth Risk Behaviour Web‐based Survey based on their racial/ethnic status, determined by their parents' birthplaces. Using multiple linear regression, we investigated whether the impact of racial/ethnic disparities on sleep health (sleep duration, debt, and timing) varies depending on substance use behaviours (alcohol and tobacco use) after controlling for age, sex, household economic status, depressed mood, suicidal ideation, perceived excessive stress, and anxiety level.

Results

Despite no statistical differences in sleep health and the prevalence of substance use between racial/ethnic groups, racial/ethnic minority adolescents experienced greater sleep debt than racial/ethnic majority adolescents when consuming alcohol. Moreover, racial/ethnic minority adolescents were more likely to report psychosocial distress and had lower parental education level.

Conclusion

Racial/ethnic minority adolescents were more vulnerable to the detrimental effects of alcohol use on sleep health compared to racial/ethnic majority adolescents. This heightened vulnerability may be attributed to the more pronounced psychosocial challenges and the lower socioeconomic status of parents in the racial/ethnic minority group.

Impact

Racial/ethnic disparities are concerning in South Korea, particularly since the negative effects of substance use on sleep health are intensified among racial/ethnic minority adolescents. Nurses and other healthcare providers should recognize the importance of addressing the social disadvantages linked to racial/ethnic disparities. Beyond just advocating for the cessation of substance use, it is crucial to address these underlying issues to reduce sleep disparities among South Korean adolescents.

Patient or Public Contribution

No patient or public contribution.
Identification and characterization of camptothecin tailoring enzymes in Nothapodytes tomentosa
Authors: Chen Yin , Huang Jian‐Ping , Wang Yong‐Jiang , Tu Meng‐Ling , Li Junheng , Xu Bingyan , Peng Guoqing , Yang Jing , Huang Sheng‐Xiong
Published: March 2024

Camptothecin is a complex monoterpenoid indole alkaloid with remarkable antitumor activity. Given that two C‐10 modified camptothecin derivatives, topotecan and irinotecan, have been approved as potent anticancer agents, there is a critical need for methods to access other aromatic ring‐functionalized congeners (e.g., C‐9, C‐10, etc.). However, contemporary methods for chemical oxidation are generally harsh and low‐yielding when applied to the camptothecin scaffold, thereby limiting the development of modified derivatives. Reported herein, we have identified four tailoring enzymes responsible for C‐9 modifications of camptothecin from Nothapodytes tomentosa, via metabolomic and transcriptomic analysis. These consist of a cytochrome P450 (NtCPT9H) which catalyzes the regioselective oxidation of camptothecin to 9‐hydroxycamptothecin, as well as two methyltransferases (NtOMT1/2, converting 9‐hydroxycamptothecin to 9‐methoxycamptothecin), and a uridine diphosphate‐glycosyltransferase (NtUGT5, decorating 9‐hydroxycamptothecin to 9‐β‐D‐glucosyloxycamptothecin). Importantly, the critical residues that contribute to the specific catalytic activity of NtCPT9H have been elucidated through molecular docking and mutagenesis experiments. This work provides a genetic basis for producing camptothecin derivatives through metabolic engineering. This will hasten the discovery of novel C‐9 modified camptothecin derivatives, with profound implications for pharmaceutical manufacture.
Market Freezes
Authors: GU CHAO , MENZIO GUIDO , WRIGHT RANDALL , ZHU YU
Published: March 2024

Market freezes are an interesting and theoretically challenging phenomenon —they are observed empirically, but cannot occur in standard models. This paper develops a formal theory of recurrent freezes emphasizing liquidity and self‐fulfilling prophecies. While it is well understood how to get hot and cold spells, where prices and quantities fluctuate, we get asset market freezes and thaws where trade completely stops and starts. The simplest specification gets this using negative asset returns. Other specifications use information frictions or fixed costs. We also consider credit freezes, analyze the extent to which the decentralized nature of trade matters, and discuss policy implications.
Nursing experiences and knowledge of paediatric delirium: Analysing knowledge‐practice gaps
Authors: Shon Soonyoung , Kang Minkyung
Published: March 2024

Background

Delirium commonly occurs in paediatric patients with acute critical illness and negatively affects clinical outcomes. Variations in delirium knowledge levels and its management have been noted among nurses.

Aims

This study investigated nurses' experiences and knowledge levels regarding paediatric delirium. Additionally, we aimed to assess the gap between knowledge levels and practical experiences with paediatric delirium.

Study Design

This cross‐sectional descriptive study conveniently sampled paediatric nurses from a university hospital in South Korea between September 2022 and March 2023. Nursing experiences with paediatric delirium and delirium knowledge levels were measured using structured survey questionnaires. Delirium knowledge was scored 0 to 47, and higher scores indicated higher levels of delirium‐related knowledge. Data were analysed using descriptive statistics and presented as mean, standard deviation, frequency and percentage.

Results

A total of 127 paediatric nurses participated in this study; 40.2% had experience with 1–5 delirium cases in the previous year, and 86.6% (n = 110) had never used assessment tools for paediatric delirium assessment. The mean total delirium knowledge score was 34.45 ± 5.4; the mean scores of knowledge regarding aetiology, signs and symptoms and nursing management of delirium were 8.93 ± 1.31, 13.24 ± 2.81 and 12.3 ± 2.7, respectively. Interventions associated with a lower level of delirium‐related knowledge and a lower performance rate included avoiding restraint use and maintaining hydration and electrolyte levels. Interventions associated with a higher level of delirium‐related knowledge but a lower rate of performance comprised providing orientation, offering emotional support, allowing participants to stay with family members and administering medications to manage delirium.

Conclusions

Although nurses working in paediatric units exhibited high rate of delirium nursing care, there was the gap between their delirium‐related knowledge and practice. Nurses need to be aware of the insufficient part of delirium care, and paediatric delirium education should be reinforced.

Relevance to Clinical Practice

Preventing, assessing and systematically managing paediatric delirium is crucial, and considering the study results, delirium education among nurses is needed.
Phenotyping xylem connections in grafted plants using X‐ray micro‐computed tomography
Authors: Camboué Marilou , Janoueix Anne , Tandonnet Jean‐Pascal , Spilmont Anne‐Sophie , Moisy Cédric , Mathieu Guillaume , Cordelières Fabrice , Teillon Jérémie , Santesteban Luis Gonzaga , Ollat Nathalie , Cookson Sarah Jane
Published: March 2024

Plants are able to naturally graft or inosculate their trunks, branches and roots together, this mechanism is used by humans to graft together different genotypes for a range of purposes. Grafts are considered successful if functional vascular connections between the two genotypes occur. Various techniques can evaluate xylem connections across the graft interface. However, these methods are generally unable to assess the heterogeneity and three‐dimensional (3D) structure of xylem vessel connections. Here we present the use of X‐ray micro‐computed tomography to characterize the 3D morphology of grafts of grapevine. We show that xylem vessels form between the two plants of natural root and human‐made stem grafts. The main novelty of this methodology is that we were able to visualize the 3D network of functional xylem vessels connecting the scion and rootstock in human‐made stem grafts thanks to the addition of a contrast agent to the roots and improved image analysis pipelines. In addition, we reveal the presence of extensive diagonal xylem connections between the main axial xylem vessels in 2‐year old grapevine stems. In conclusion, we present a method that has the potential to provide new insights into the structure and function of xylem vessels in large tissue samples.
The development of pleiotropic phenotypes in powdery mildew‐resistant barley and Arabidopsis thaliana mlo mutants is linked to nitrogen availability
Authors: Freh Matthias , Reinstädler Anja , Neumann Kira D. , Neumann Ulla , Panstruga Ralph
Published: March 2024

Powdery mildew‐resistant barley (Hordeum vulgare) and Arabidopsis thaliana mlo mutant plants exhibit pleiotropic phenotypes such as the spontaneous formation of callose‐rich cell wall appositions and early leaf chlorosis and necrosis, indicative of premature leaf senescence. The exogenous factors governing the occurrence of these undesired side effects remain poorly understood. Here, we characterised the formation of these symptoms in detail. Ultrastructural analysis revealed that the callose‐rich cell wall depositions spontaneously formed in A. thaliana mlo mutants are indistinguishable from those induced by the bacterial pattern epitope, flagellin 22 (flg22). We further found that increased plant densities during culturing enhance the extent of the leaf senescence syndrome in A. thaliana mlo mutants. Application of a liquid fertiliser rescued the occurrence of leaf chlorosis and necrosis in both A. thaliana and barley mlo mutant plants. Controlled fertilisation experiments uncovered nitrogen as the macronutrient whose deficiency promotes the extent of pleiotropic phenotypes in A. thaliana mlo mutants. Light intensity and temperature had a modulatory impact on the incidence of leaf necrosis in the case of barley mlo mutant plants. Collectively, our data indicate that the development of pleiotropic phenotypes associated with mlo mutants is governed by various exogenous factors.
CERK1 compromises Fusarium solani resistance by reducing jasmonate level and undergoes a negative feedback regulation via the MMK2‐WRKY71 module in apple
Authors: Pei Tingting , Zhan Minghui , Niu Dongshan , Liu Yuerong , Deng Jie , Jing Yuanyuan , Li Pengmin , Liu Changhai , Ma Fengwang
Published: March 2024

Fusarium spp., a necrotrophic soil‐borne pathogen, causes root rot disease on many crops. CERK1, as a typical pattern recognition receptor, has been widely studied. However, the function of CERK1 during plant–Fusarium interaction has not been well described. We determined that MdCERK1 is a susceptibility gene in the apple‐Fusarium solani (Fs) interaction, and jasmonic acid (JA) plays a crucial role in this process. MdCERK1 directly targets and phosphorylates the lipoxygenase MdLOX2.1, an enzyme initiating the JA biosynthesis, at positions Ser326 and Thr327. These phosphorylations inhibit its translocation from the cytosol to the chloroplasts, leading to a compromised JA biosynthesis. Fs upregulates MdCERK1 expression during infection. In turn, when the JA level is low, the apple MdWRKY71, a transcriptional repressor of MdCERK1, is markedly upregulated and phosphorylated at Thr99 and Thr102 residues by the MAP kinase MdMMK2. The phosphorylation of MdWRKY71 enhances its transcription inhibition on MdCERK1. Taken together, MdCERK1 plays a novel role in limiting JA biosynthesis. There seems to be an arms race between apple and Fs, in which Fs activates MdCERK1 expression to reduce the JA level, while apple senses the low JA level and activates the MdMMK2‐MdWRKY71 module to elevate JA level by inhibiting MdCERK1 expression.
Platelet transfusions in haploidentical haematopoietic stem cell allograft candidates: Protecting HLA‐A and HLA‐B antigens through eplet analysis
Authors: Durand Gatien , Desoutter Judith , Lorriaux Corinne , Poumaredes Géraldine , Joris Magalie , Charbonnier Amandine , Lebon Delphine , Paubelle Etienne , Garcon Loïc , Guillaume Nicolas
Published: March 2024

In patients awaiting an allogeneic haematopoietic stem cell transplantation, platelet transfusion is a risk factor for anti‐HLA class I immunization because the resulting donor‐specific antibodies complicate the allograft process. The objective of the present study was to determine the feasibility of a novel eplet‐based strategy for identifying HLA class I mismatches between potential donors and the recipient when pre‐allograft platelet transfusions were required. We included 114 recipient/haploidentical relative pairs. For each pair, we entered HLA‐class I typing data into the HLA Eplet Mismatch calculator, defined the list of mismatched eplets (for the recipient versus donor direction) and thus identified the shared HLAs to be avoided. Using this list of HLAs, we defined the theoretical availability of platelet components (PCs) by calculating the virtual panel‐reactive antibody (vPRA). We also determined the number of PCs actually available in France by querying the regional transfusion centre's database. The mean ± standard deviation number of highly/moderately exposed eplets to be avoided in platelet transfusions was 5.8 ± 3.3, which led to the prohibition of 38.5 ± 2 HLAs‐A and ‐B. Taking into account the mismatched antigens and the eplet load, the mean ± standard deviation theoretical availability of PCs (according to the vPRA) was respectively 34.49% ± 1.95% for HLA‐A and 80% ± 2.3% for HLA‐B. A vPRA value below 94.9% for highly or moderately exposed eplets would predict that 10 PCs were actually available nationally. Although epitope protection of HLA molecules is feasible, it significantly restricts the choice of PCs.
Charles Waller and Edward Doubleday—Colleagues of James Blundell and early supporters of blood transfusion
Authors: Learoyd Phil
Published: March 2024

The obstetrician James Blundell performed the first human‐to‐human blood transfusion in England during the early part of the 19th century arguing that it could be used as a treatment for post‐partum haemorrhage. During this period, Blundell personally acknowledged two of his medical colleagues Charles Waller and Edward Doubleday as being strong supporters of the use of blood transfusion. This paper outlines the roles that these two men played in the early history of blood transfusion.
A root‐knot nematode effector targets the Arabidopsis cysteine protease RD21A for degradation to suppress plant defense and promote parasitism
Authors: Yu Jiarong , Yuan Qing , Chen Chen , Xu Tianyu , Jiang Yuwen , Hu Wenjun , Liao Aolin , Zhang Jiayi , Le Xiuhu , Li Hongmei , Wang Xuan
Published: March 2024

Meloidogyne incognita is one of the most widely distributed plant‐parasitic nematodes and causes severe economic losses annually. The parasite produces effector proteins that play essential roles in successful parasitism. Here, we identified one such effector named MiCE108, which is exclusively expressed within the nematode subventral esophageal gland cells and is upregulated in the early parasitic stage of M. incognita. A yeast signal sequence trap assay showed that MiCE108 contains a functional signal peptide for secretion. Virus‐induced gene silencing of MiCE108 impaired the parasitism of M. incognita in Nicotiana benthamiana. The ectopic expression of MiCE108 in Arabidopsis suppressed the deposition of callose, the generation of reactive oxygen species, and the expression of marker genes for bacterial flagellin epitope flg22‐triggered immunity, resulting in increased susceptibility to M. incognita, Botrytis cinerea, and Pseudomonas syringae pv. tomato (Pst) DC3000. The MiCE108 protein physically associates with the plant defense protease RD21A and promotes its degradation via the endosomal‐dependent pathway, or 26S proteasome. Consistent with this, knockout of RD21A compromises the innate immunity of Arabidopsis and increases its susceptibility to a broad range of pathogens, including M. incognita, strongly indicating a role in defense against this nematode. Together, our data suggest that M. incognita deploys the effector MiCE108 to target Arabidopsis cysteine protease RD21A and affect its stability, thereby suppressing plant innate immunity and facilitating parasitism.
Multispectral brain connectivity during visual attention distinguishes controlled from uncontrolled hypertension
Authors: Son Jake J. , Arif Yasra , Oludipe Davina , Weyrich Lucas , Killanin Abraham D. , Wiesman Alex I. , Okelberry Hannah J. , Willett Madelyn P. , Johnson Hallie J. , Wilson Tony W.
Published: March 2024

Hypertension‐related changes in brain function place individuals at higher risk for cognitive impairment and Alzheimer's disease. The existing functional neuroimaging literature has identified important neural and behavioural differences between normotensive and hypertensive individuals. However, previously‐used methods (i.e. magnetic resonance imaging, functional near‐infrared spectroscopy) rely on neurovascular coupling, which is a useful but indirect measure of neuronal activity. Furthermore, most studies fail to distinguish between controlled and uncontrolled hypertensive individuals, who exhibit significant behavioural and clinical differences. To partially remedy this gap in the literature, we used magnetoencephalography (MEG) to directly examine neuronal activity that is invariant to neurovascular coupling changes induced by hypertension. Our study included 52 participants (19 healthy controls, 15 controlled hypertensives, 18 uncontrolled hypertensives) who completed a modified flanker attention task during MEG. We identified significant oscillatory neural responses in two frequencies (alpha: 8–14 Hz, gamma: 48–60 Hz) for imaging and used grand‐averaged images to determine seeds for whole‐brain connectivity analysis. We then conducted Fisher‐z tests for each pair of groups, using the relationship between the neural connectivity and behavioural attention effects. This highlighted a distributed network of regions associated with cognitive control and selective attention, including frontal‐occipital and interhemispheric occipital connections. Importantly, the inferior frontal cortex exhibited a unique neurobehavioural relationship that distinguished the uncontrolled hypertensive group from the controlled hypertensive and normotensive groups. This is the first investigation of hypertension using MEG and identifies critical whole‐brain connectivity differences based on hypertension profiles.

image

Key points

Structural and functional changes in brain circuitry scale with hypertension severity and increase the risk of cognitive impairment and Alzheimer's disease.

We harness the excellent spatiotemporal precision of magnetoencephalography (MEG) to directly quantify dynamic functional connectivity in healthy control, controlled hypertensive and uncontrolled hypertensive groups during a flanker task.

In the first MEG study of hypertension, we show that there are neurobehavioural relationships that distinguish the uncontrolled hypertensive group from healthy and controlled hypertensive group in the prefrontal cortex.

These results provide novel insights into the differential impact of hypertension on brain dynamics underlying selective attention.
Modeling of Soil Water Distribution in a Small Mid-Latitude Watershed on the British Isle for Short Term Landslide and Flood Risk Assessment
Authors: Karam Hugo Abi , Blackett Matthew Alexander , Silva Raphaella Barros Pereira da , Flores Rojas Jose Luis , Pereira Filho Augusto José , Peña Cesar Arturo Sanchez , Vásquez Isela Leonor , Siqueira Brenda Santos , Suazo Julio Miguel Angeles
Published: March 2024

The R-TopModel hydrological model coupled with two landslide and flood probability distribution models was applied to simulate the daily hydrological conditions of a small catchment in the Midlands of the British Isles, throughout 2017. Originally, the methodology was applied to a risk area in the tropical region. In this work, the application was extended to mid-latitude watersheds. The hydrographic basin around the Carsington Water dam (located in the Midlands of the Great Britain) is chosen because it presents risks. The model Nash-Sutcliffe Efficiency for the upstream discharge from the Carsington Water dam reached 50% with a correlation coefficient of the order of 70%, an acceptable value considering the seasonal effects of the dam on evapotranspiration and higher soil permeability. Modeling the distribution of soil moisture and excess surface water allowed obtaining the spatial distribution of the maximum conditional probability of landslides and floods in the Carsington Water catchment. These probability maps obtained are consistent with long-term susceptibility maps for Great Britain.
Exploration of High-Frequency Actuation on Gust Response Using Large Eddy Simulation
Authors: Barnes Caleb J.
Published: March 2024

Mitigation of gust-induced separation and aerodynamic loads using a high-frequency blowing/suction slot is demonstrated using high-order implicit large eddy simulation (LES). This approach was previously shown to be effective at alleviating dynamic stall on pitching wings. A NACA0012 wing section operating at a transitional chord-based Reynolds number of Rec=500,000, subsonic freestream Mach number of M∞=0.1, and angles of attack of α = 4 deg and 12 deg is subjected to discrete 1-cos transverse gusts. Gust-induced stall is demonstrated and then active flow control (AFC) is applied to cases vulnerable to gust-induced stall. The flow control strategy is shown to be effective at stall suppression during gust encounter, thereby providing partial alleviation of gust induced loads. This approach is most effective at attenuating pitching moment increment.
Numerical Research on Impacting Load and Structural Response for a Model Experiment of High-Speed Craft
Authors: Liu Weiqin , Qin Yuxin , Hu Yuchen , Vladimir Nikola , Xu Shuangxi , Wu Yigang
Published: March 2024

High-speed craft typically utilizes hydroplane boat-type and large power engine to obtain high-speed in water. However, these designs result in significant hydrodynamic nonlinearities, including slamming, wetness, sliding, and dolphin effect. As a result, high-speed craft exhibits complex impact load characteristics and structural responses, which have garnered considerable attention from ship mechanics researchers. This paper studies impacting load and structural response of a high-speed craft by means of numerical approach that combines computational fluid dynamics (CFD) and finite element method (FEM). A model experiment of high-speed craft is selected to simulate impact load and structural response. The craft model consists of two ship bodies and a keel beam, and a number of pressure sensors and strain gaugesare arranged to capture the impacting pressure and vertical bending moment (VBM). A numerical fluid-structure interaction (FSI) approach is employed to investigate the model experiment of the high-speed craft by coupling CFD and FEM. CFD is utilized to solve the hydrodynamics of the high-speed craft. Dynamics of fluid-body interaction (DFBI) and overset grid algorithm are employed to accurately simulate the motion of the craft. Dynamic FEM is used to calculate structural response of high-speed craft, structural VBM is obtained. Two-way FSI is employed to realize coupling of CFD and FEM. This involves iterating the wave pressures and structural displacement to make progress. Ultimately, the numerical results and experimental results, which encompass impacting pressure, craft motion, and VBM, are compared and analyzed, demonstrating a high degree of agreement. Numerical methods can be employed to analyze the impacting load and structural response for high-speed craft.
EL GIRO ONTOLÓGICO EN EL RECONOCIMIENTO JURISPRUDENCIAL DE LOS DERECHOS DE LOS NO HUMANOS EN COLOMBIA. EL CASO DEL ÁREA PROTEGIDA VÍA PARQUE ISLA DE SALAMANCA
Authors:   Université de Liége, Márquez Guerra José Francisco
Published: March 2024

"En el mundo contemporáneo se constata la insuficiencia de los marcos ontológicos y epistemológicos de las denominadas ciencias de la gestión ambiental, lo que vuelve problemático el rol de la protección de los complejos socio ecológicos. Las formas jurídicas tradicionales al ser concebidas desde una ontología naturalista escapan a la comprensión de la diversidad poniendo en riesgo el modo de existencia de los otros y sus mundos relacionales con los no humanos. Este texto presenta un panorama sobre las concepciones en que se abordan los problemas ambientales desde su perspectiva occidental, basados en la representación tecnocientífica de la “Naturaleza” y el modelo multicultural de gestión de la diversidad cultural en la jurisprudencia colombiana. Como ejemplo se plantea la manera en que la síntesis de las discusiones antropológicas es reutilizada en los argumentos de las decisiones de las Cortes de justicia en Colombia sobre los derechos de la naturaleza aplicando conceptos como ontologías relacionales o derechos bioculturales, pero imponiendo en la práctica fórmulas de gestión occidentales. Se analiza el caso de la declaratoria de la Vía Parque Isla de Salamanca -un área protegida de manglares con una importante presión antrópica- como sujeto de derechos y el sistema de protección adoptado por vía jurisprudencial. Se evalúan los impactos de la decisión sobre los propósitos de conservación de la biodiversidad y sobre los derechos de las poblaciones humanas tradicionales habitantes dentro y en la zona de influencia del Parque Natural. Se discute cómo el giro ontológico (la toma en cuenta de la multiplicidad de las formas de relación Culturas/ Naturaleza) proveniente de los debates antropológicos contemporáneos ha evidenciado la necesidad de repensar el concepto de sujetos de derechos y su extensión a los seres no humanos, así como los escollos para su incorporación efectiva a las prácticas de la gestión ambiental en áreas protegidas "
Modeling and simulation of underwater acoustic propagation through a random distribution of ice blocks
Authors: Chotiros Nicholas P. , Holm Sverre
Published: March 2024

Acoustic propagation through a random distribution of 1 m ice cubes, from 100 to 1000 Hz, was simulated in a 3D finite element model. The effective sound speed and attenuation as functions of frequency were calculated from the simulated signals. Attempts were made to fit a number of models to the wave speed and attenuation, including single scattering, lossy water, and Biot approximations. An extended Biot model, developed for acoustic propagation in granular seabed sediments, was able to fit the simulation up to 300 Hz. Beyond this frequency, the simulation shows that multiple scattering dominates.
Specific interaction between Group B
Streptococcus
CC17 hypervirulent clone and phagocytes
Authors: Bourrel Anne-Sophie , Picart Amandine , Fernandez Jose-Carlos , Hays Constantin , Mignon Virginie , Saubaméa Bruno , Poyart Claire , Fouet Agnès , Tazi Asmaa , Guignot Julie
Published: March 2024

Streptococcus agalactiae
also named Group B
Streptococcus
(GBS) is the most significant pathogen causing invasive infections, such as bacteremia and meningitis, in neonates. Worldwide epidemiological studies have shown that a particular clonal complex (CC) of capsular serotype III, the CC17, is strongly associated with meningitis in neonates and is therefore, designated as the hypervirulent clone. Macrophages are a permissive niche for intracellular bacteria of all GBS clones. In this study, we deciphered the specific interaction of GBS CC17 strains with macrophages. Our study revealed that CC17 strains are phagocytosed at a higher rate than GBS non-CC17 strains by human monocytes and macrophages both in cellular models and in primary cells. CC17-enhanced phagocytosis is due to an initial enhanced-attachment step to macrophages mediated by the CC17-specific surface protein HvgA and the PI-2b pilus (Spb1). We showed that two different inhibitors of scavenger receptors (fucoidan and poly(I)) specifically inhibited CC17 adhesion and phagocytosis while not affecting those of non-CC17 strains. Once phagocytosed, both CC17 and non-CC17 strains remained in a LAMP-1 positive vacuole that ultimately fuses with lysosomes where they can survive at similar rates. Finally, both strains displayed a basal egress which occurs independently from actin and microtubule networks. Our findings provide new insights into the interplay between the hypervirulent GBS CC17 and major players of the host’s innate immune response. This enhanced adhesion, leading to increased phagocytosis, could reflect a peculiar capacity of the CC17 lineage to subvert the host immune defenses, establish a niche for persistence or disseminate.
Harms and Benefits Inventory (HBI): initial validation of a novel assessment of perceived harms and benefits of firearm policies and practices
Authors: Grasso Damion , Raissian Kerri M , Doucette L , McGuire Austen Bradley , Dineen Jennifer Necci
Published: March 2024

Introduction

Understanding gun owners’ perceptions of potential firearm policies’ harms and benefits is critical to successful policy development and implementation. We used national survey data to develop and validate a novel instrument, the Harms and Benefits Inventory (HBI), for policy-makers and advocates to better consider the citizen perspective.

Method

We conducted a nationally representative survey of American gun owners and non-owners (N=2007) using the Social Science Research Solutions probability panel. The survey included 31 candidate HBI items and questions about gun ownership and exposure, storage and carry behaviours, policy positions, and sociodemographic characteristics. Exploratory factor analyses (EFAs) were conducted on HBI items from a randomly selected subsample (N=1003) and then tested with a confirmatory factor analysis (CFA) on data from the second half of the sample (N=1004).

Results

The best-fitting EFA model was upheld in the CFA and included 21 items with 5 underlying factors. Underlying factors included: (1) firearm regulation, cost and accessibility, (2) special restrictions, (3) permit and education, (4) relaxed restrictions and (5) and hobby and sport. Internal consistency was good to excellent within each of the five scales. Validity was supported by correlations between HBI scales and survey questions.

Discussion

Findings support the validity of the HBI in assessing perceptions of potential harms and benefits of firearm policies and practices. Understanding perceptions of potential harms and benefits of gun policies at the time of development or implementation can improve uptake and reduce unintended consequences of these policies.
Differences in life history patterns of American shad (Alosa sapi dissima) populations between ancestral, Atlantic coast, and non-native Pacific coast rivers of North America
Authors: Quinn Thomas P. , Wetzel Lisa A. , Hasselman Daniel J. , Larsen Kim
Published: March 2024

Organisms naturalized outside their native range can reveal new life history patterns in new environments. Here, we compare life history patterns of American shad, Alosa sapidissima, from five rivers along the U.S. Pacific coast (introduced range) with contemporary data from the Atlantic coast source populations. The Pacific coast fish grew slower, matured at a younger age, and were less often iteroparous than conspecifics from the Hudson River and Susquehanna River sources. Differences among the Pacific coast populations indicated that some combination of phenotypic plasticity and genetic adaptation has occurred since the transplants in the 1870s. Microchemical analysis of otoliths from returning adults demonstrated an immature, extended freshwater life history form, locally known as “mini-shad”. These fish remain in the river for at least 1 year or enter salt water briefly and then return to fresh water for several months prior to subsequent seaward migration and return as adults. This and other forms of variation (extent of estuary use and size at sea water entry) expand the understanding of Alosine migration and life history diversity.
Optimizing high-dimensional forestry for wood production and carbon sinks
Authors: Tahvonen Olli , Suominen Antti , Parkatti Vesa-Pekka , Malo Pekka
Published: March 2024

Our model for optimizing stand-level wood production and carbon sinks includes individual-tree models for forest growth, an advanced model for soil carbon, detailed wood production economy, and an intertemporal objective for the value of wood production and carbon sinks/emissions. Carbon stocks include aboveground biomass and carbon in forest soil and in wood products. Optimization of the management regime, rotations and thinning timing, and type and intensity are carried out by reinforcement learning. Including the social price of carbon causes a regime switch from continuous cover forestry to clear-cuts, postponed lighter thinning, and a longer rotation, and with a high carbon price, to solutions with pure clear-cuts or solutions utilizing stands as pure carbon stocks. Carbon price has profound effects on stand values, and the bare land value may well exceed the value before a clear-cut. The total average carbon stock is maximized with harvest and a long rotation instead of “no harvesting”. Bioenergy, carbon capture, and storage (BECCS) always increases the value of wood production but not necessarily the value of carbon sinks. With BECCS, increasing carbon stocks in trees and forest soil remains optimal.
Investigation of optical spectroscopy in W13+ ions
Authors: Niu Ben , Chen Jihui , Li Bingli , Zhang Yizhuo , Zhang Ling , Meng Ju , Xiao Jun , Fu Yunqing , Yao Ke
Published: March 2024

This study presents the investigation of magnetic dipole transition lines of W13+ ions in the wavelength range of 200–700 nm at a low-energy electron beam ion trap. Seventeen lines emitted from W13+ ions have been observed with three being reported experimentally for the first time. The atomic structure calculation and spectra simulation of W13+ ions have been carried out using the multiconfiguration Dirac–Hartree–Fock method combined with the relativistic configuration interaction approach and the collisional–radiative model, respectively. The theoretical calculations are in reasonable agreement with the experimental observations, and most of the observed lines have been identified.
Study on flame retardant properties of epoxy composites using circular economy material hydroxyapatite combined with DOPO-HQ
Authors: Shen Ming-Yuan , Kuan Chen-Feng , Kuan Hsu-Chiang , Lin Lu-Ying , Chiang Chin-Lung
Published: March 2024

In this study, hydroxyapatite (HA) was extracted from biological waste. HA was modified by N,N-diglycidylaniline (NDY) and DOPO-HQ to obtain the flame retardant which was added to epoxy resin (EP) to prepare the composite. The flame retardancy of the composites was measured by the horizontal and vertical combustion tester (UL-94) and the limiting oxygen index (LOI), the thermal property was carried out by the thermogravimetric analyzer (TGA), and the surface morphology was observed by the field emission scanning electron microscope (SEM). The UL-94 grade of pure EP is a fail grade, and the LOI value was 22%. After adding HA-NDY-DOPOHQ (weight ratio 1:2:1) 40[Formula: see text]wt.% flame retardant, the UL-94 grade of the composites was raised to V-1, and the LOI value promoted to 28%, a total increase of 6%. Composite materials had excellent thermal stability and flame retardancy and could be used in fireproof panels for energy storage systems to prevent thermal runaway, and could also be used in building materials.
Exponential convergence to steady-states for trajectories of a damped dynamical system modeling adhesive strings
Authors: Coclite Giuseppe Maria , De Nitti Nicola , Maddalena Francesco , Orlando Gianluca , Zuazua Enrique
Published: March 2024

We study the global well-posedness and asymptotic behavior for a semilinear damped wave equation with Neumann boundary conditions, modeling a one-dimensional linearly elastic body interacting with a rigid substrate through an adhesive material. The key feature of of the problem is that the interplay between the nonlinear force and the boundary conditions allows for a continuous set of equilibrium points. We prove an exponential rate of convergence for the solution towards a (uniquely determined) equilibrium point.
Epidemics and society — A multiscale vision from the small world to the globally interconnected world
Authors: Burini Diletta , Knopoff Damian A.
Published: March 2024

This paper shows how a new theory of epidemics can be developed for viral pandemics in a globally interconnected world. The study of the in-host dynamics and, in parallel, the spatial diffusion of epidemics defines the goal of our work, which looks ahead to new mathematical tools to model epidemics beyond the traditional approach of population dynamics. The approach takes into account the evolutionary nature of the virus, which can generate pseudo-Darwinian mutations and selection, while learning the presence of the virus and activating adaptive immunity. The study of immune competition plays a key role in both the in-host dynamics and the contagion dynamics.
Vehicle Response-Based Bridge Modal Identification Using Different Time–Frequency Analysis Methods
Authors: Kong Xuan , Tang Quanyu , Luo Kui , Hu Jiexuan , Li Jinzhao , Cai C. S.
Published: March 2024

Modal identification of bridges based on the responses of moving vehicles, termed as the indirect method, has drawn much attention in recent years. This indirect method has been proven to be capable of identifying bridge frequencies and mode shapes in the feasibility research. However, in the presence of additional factors such as vehicle speed and road surface roughness, it is difficult to identify high-order frequencies and high-resolution mode shapes of the bridge. The authors previously proposed a tractor-double-trailers model and the time–domain subtraction method to obtain the relative displacement of two trailers for bridge modal identification. In this study, the authors develop a methodology to improve the identification performance by combining the EMD technique and the time–frequency analysis method. The EMD technique is applied to separate the multi-source response signals of the trailers to obtain the signal component that contains only the bridge vibration. Then, different time–frequency analysis methods such as the short-time Fourier transform (STFT), Wigner–Ville distribution (WVD), and continuous wavelet transform (CWT) are adopted to construct the high-resolution bridge mode shapes. Numerical studies with one-dimensional and three-dimensional bridge models are conducted to verify the proposed method and investigate the effects of different factors. Finally, a laboratory test is implemented on a scaled bridge to verify the performance of the proposed method. The results show that the proposed method is able to separate the vehicle frequency and bridge frequencies, which facilitates the identification of bridge frequencies from the dynamic response of moving vehicles. Meanwhile, the CWT method performs the best in the identification of modal shapes among the three time–frequency analysis methods.