bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progressive Damage Analysis of Curved Composite Laminates Incorporating Effects of Manufacturing Using a Semi-Discrete Damage Model
Authors: Meka Sai Krishna , Enos Ryan , Roach James , Zhang Dianyun 
Published: June 2024

Abstract
This study underscores the remarkable strength-to-weight advantage offered by curved composite laminates in comparison to conventional materials like metal, preserving or even surpassing strength levels. To comprehensively assess the strength characteristics of such laminates, the research delves into the primary failure modes governing their out-of-plane strength, predominantly matrix failure and delamination. It is essential to consider the impact of manufacturing processes, which introduce residual stresses and spring-in phenomena.
To address these complexities, a finite element simulation is employed, integrating manufacturing effects and adopting a semi-discrete damage model. Within this model, matrix failure within the plies is delineated using a smeared crack approach, whereby crack directionality aligns passively with fiber orientation within each ply. Furthermore, the smeared crack approach is extended to model damage occurring at ply interfaces.
This comprehensive investigation is done for the layup sequence: [45°/0°/−45°/90°]3S - symmetric and balanced laminate. Experimental validation is achieved through a 4-point bending test by adhering close to ASTM D6415 standards, gauging the curved beam strength/inter-laminar strength of fiber-reinforced polymer matrix composites. The utilization of DIC images aids in the systematic observation and comprehension of failure modes across various scenarios.
Novel Polyetheretherketone/Polytetrafluoroethylene Composites Reinforced With Titanium Silicon Carbide for Conveyor Chute
Authors: Ahmed Nihal , Okolie Nzubechukwu , Ghosh Sujan 
Published: June 2024

Abstract
The e-commerce industry has witnessed unprecedented growth in recent years, accelerated by the global pandemic and changing consumer behaviors. This demand has placed great strain on traditional conveyor chute materials, causing high friction and wear, leading to high maintenance costs and reduced operational efficiency. In this research, Polyetheretherketone (PEEK) + Polytetrafluoroethylene (PTFE) + MAX phases (Ti3SiC2) nanocomposite materials were tested for conveyor chute applications. The composite was fabricated by mixing the powder in a specific weight ratio, pressing them in a die, and finally sintering the pressed disc at 300°C. Tribological tests were performed in linear reciprocating motion using a Cr-Steel counterface. The nanocomposite materials show a COF of 0.06, lower than the PEEK and PTFE materials. More importantly, when tested under the same condition, the PTFE+PEEK+MAX phases composite showed a one-degree lower wear rate than the PEEK and PTFE materials. The microscope image shows that the physical presence of MAX phases helps the composites to attain better compaction, higher hardness, and better load-carrying capacity. The materials’ better compression and enhanced hardness help improve the composite’s tribological properties. Moreover, the better compaction of the PTFE+PEEK+MAX composite increases the water contact angle of these materials compared to the PTFE and PEEK materials. This novel composite can be an excellent replacement for the current materials used for conveyor chute applications.
Fatigue Delamination Damage Sensing and Self-Healing in Thermoset Composites Using Thermoplastic Healants
Authors: Vishe Nilesh J. , Aditya Sankha S. , Mulani Sameer B. , Roy Samit 
Published: June 2024

Abstract
In this study, fatigue testing under mode-I loading and damage (delamination) detection tests were carried out on double cantilever beam (DCB) specimens, and subsequent healing of the delamination was investigated. Due to the susceptibility of laminated composites to delamination, fatigue delamination is one of the critical damage modes in laminated composites and can lead to catastrophic failure if it is allowed to proceed unchecked. Hence, it is necessary to investigate and quantify the delamination crack growth behavior due to fatigue loading and to accurately predict the size of the delamination crack and then to heal it in situ in a repeatable manner. A DCB specimen with an array of 8 MFCs was used to detect damage with the actuation signal as anti-symmetric Lamb wave excitation. The signal difference coefficient (SDC) was used as a delamination detection metric and calculated for different actuator and sensor location combinations.
Same Game, Many Cultures: A Multicultural Reflection on a Trainee’s Intervention Work With a Professional Esports Team
Authors: Agrawal Anjali , Gupta Sahen , Swettenham Laura 
Published: June 2024

This applied case study aims to explore the experience and multicultural reflections of a trainee sport and exercise psychologist working with a professional, multicultural esports team. We showcase the context of the case with a League of Legends team, consisting of five players, along with the intervention conducted. The case is supplemented by critical reflections on practice in a multicultural context from learning logs and applied practice notes with the T-R-E-E-S model for multicultural practice in sport psychology. This study delves into several critical aspects, namely: (a) recognizing multicultural elements, (b) customizing interventions to the dynamic esports environment, (c) scrutinizing how language and culture impact team cohesion, and (d) considering individual boundaries in personal-disclosure interventions. Finally, as one of the first case studies to reflect on multicultural practice in esports, we provide key recommendations and implications to promote multicultural work in research and applied practice in esports.
A CRISPR-Cas-associated transposon system for genome editing in
Burkholderia cepacia
complex species
Authors: Yap Zhong Ling , Rahman A. S. M. Zisanur , Hogan Andrew M. , Levin David B. , Cardona Silvia T. 
Published: June 2024

ABSTRACT

Genome editing in non-model bacteria is important to understand gene-to-function links that may differ from those of model microorganisms. Although species of the
Burkholderia cepacia
complex (Bcc) have great biotechnological capacities, the limited genetic tools available to understand and mitigate their pathogenic potential hamper their utilization in industrial applications. To broaden the genetic tools available for Bcc species, we developed RhaCAST, a targeted DNA insertion platform based on a CRISPR-associated transposase driven by a rhamnose-inducible promoter. We demonstrated the utility of the system for targeted insertional mutagenesis in the Bcc strains
B. cenocepacia
K56-2 and
Burkholderia multivorans
ATCC17616. We showed that the RhaCAST system can be used for loss- and gain-of-function applications. Importantly, the selection marker could be excised and reused to allow iterative genetic manipulation. The RhaCAST system is faster, easier, and more adaptable than previous insertional mutagenesis tools available for Bcc species and may be used to disrupt pathogenicity elements and insert relevant genetic modules, enabling Bcc biotechnological applications.

IMPORTANCE

Species of the
Burkholderia cepacia
complex (Bcc) have great biotechnological potential but are also opportunistic pathogens. Genetic manipulation of Bcc species is necessary to understand gene-to-function links. However, limited genetic tools are available to manipulate Bcc, hindering our understanding of their pathogenic traits and their potential in biotechnological applications. We developed a genetic tool based on CRISPR-associated transposase to increase the genetic tools available for Bcc species. The genetic tool we developed in this study can be used for loss and gain of function in Bcc species. The significance of our work is in expanding currently available tools to manipulate Bcc.
A riboswitch-controlled TerC family transporter Alx tunes intracellular manganese concentration in
Escherichia coli
at alkaline pH
Authors: Sharma Ravish , Mishanina Tatiana V. 
Published: June 2024

ABSTRACT

Cells use transition metal ions as structural components of biomolecules and cofactors in enzymatic reactions, making transition metal ions integral cellular components. Organisms optimize metal ion concentration to meet cellular needs by regulating the expression of proteins that import and export that metal ion, often in a metal ion concentration-dependent manner. One such regulation mechanism is via riboswitches, which are 5′-untranslated regions of an mRNA that undergo conformational changes to promote or inhibit the expression of the downstream gene, commonly in response to a ligand. The
yybP-ykoY
family of bacterial riboswitches shares a conserved aptamer domain that binds manganese ions (Mn
2+
). In
Escherichia coli
, the
yybP-ykoY
riboswitch precedes and regulates the expression of two different genes:
mntP
, which based on genetic evidence encodes an Mn
2+
exporter, and
alx
, which encodes a putative metal ion transporter whose cognate ligand is currently in question. The expression of
alx
is upregulated by both elevated concentrations of Mn
2+
and alkaline pH. With metal ion measurements and gene expression studies, we demonstrate that the alkalinization of media increases the cytoplasmic manganese pool, which, in turn, enhances
alx
expression. The Alx-mediated Mn
2+
export prevents the toxic buildup of the cellular manganese, with the export activity maximal at alkaline pH. We pinpoint a set of acidic residues in the predicted transmembrane segments of Alx that play a critical role in Mn
2+
export. We propose that Alx-mediated Mn
2+
export serves as a primary protective mechanism that fine tunes the cytoplasmic manganese content, especially during alkaline stress.

IMPORTANCE

Bacteria use clever ways to tune gene expression upon encountering certain environmental stresses, such as alkaline pH in parts of the human gut and high concentration of a transition metal ion manganese. One way by which bacteria regulate the expression of their genes is through the 5′-untranslated regions of messenger RNA called riboswitches that bind ligands to turn expression of genes on/off. In this work, we have investigated the roles and regulation of
alx
and
mntP
, the two genes in
Escherichia coli
regulated by the
yybP-ykoY
riboswitches, in alkaline pH and high concentration of Mn
2+
. This work highlights the intricate ways through which bacteria adapt to their surroundings, utilizing riboregulatory mechanisms to maintain Mn
2+
levels amidst varying environmental factors.
Flying microbes—survival in the extreme conditions of the stratosphere during a stratospheric balloon flight experiment
Authors: Heitkämper Tim , Roth Raphael , Harteneck Stephan , Berger Felix , Salam Sonya , Fey-Du Chunyu , Flöck Christopher , Tschierske Niclas , Vonderbank Vincent , Martin Alexander , Erren Sebastian , Zimmermann Joel , Lutz Mike , Kujala Katharina 
Published: June 2024

ABSTRACT

Earth’s stratosphere is characterized by hypobaric conditions, low temperatures, and high intensities of ultraviolet (UV) and cosmic radiation as well as low water and nutrient availability. While it is not considered a permanent habitat for microorganisms, they can be transported to the stratosphere by storms, volcanic action, or human activity. The impact of those extreme conditions on microorganisms and their survival were tested by sending a sample gondola to the stratosphere. The sample gondola was built to allow exposure of
Bacillus subtilis
endospores at different angles to the sun. It moreover had holders for three environmental samples to test the effect of stratospheric conditions on complex microbial communities. The gondola attached to a stratospheric balloon was launched near Kiruna, Sweden, ascended to ~25 km, and drifted eastward for ~200 km. Samples were exposed to pressures as low as 2 kPa and temperatures as low as −50°C as well as high UV radiation. Survival rates of
B. subtilis
were determined by comparing the numbers of colony-forming units (CFUs) for the different exposure angles. Survival was negatively correlated with exposure angle, indicating the significant impact of UV radiation. The effect of stratospheric conditions on environmental samples was assessed by comparing most probable numbers, microbial community composition, and substrate-use profiles to controls that had stayed on the ground. Cultivation was possible from all samples with survival rates of at least 1%, and differences in community composition were observed. Survival of environmental microorganisms might have been supported by the sample matrix, which provided protection from radiation and desiccation.

IMPORTANCE

Earth's stratosphere is a hostile environment that has challenged microbial survival. We set out to test the effect of stratosphere exposure on survival of single species (
Bacillus subtilis
) and complex microbial communities from soils and sediment.
B. subtilis
survival was strongly impacted by sun exposure, i.e., ultraviolet (UV) radiation, with only 1% survival at full sun exposure. Complex microbial communities had high survival rates, and the soil or sediment matrix may have provided protection against radiation and desiccation, supporting the survival of environmental microorganisms.
Generation of Archean TTGs via sluggish subduction
Authors: Foley Bradford J. 
Published: June 2024

Abstract
The trondhjemite-tonalite-granodiorite (TTG) suite of rocks prominent in Earth’s Archean continents is thought to form by melting of hydrated basalt, but the specific tectonic settings of formation are unclear. Models for TTG genesis range from melting of downgoing mafic crust during subduction into a hotter mantle to melting at the base of a thick crustal plateau; while neither uniquely defines a global tectonic regime, the former is consistent with mobile lid tectonics and the latter a stagnant lid. One major problem for a subduction model is slabs sinking too quickly and steeply in a hotter mantle to melt downgoing crust. I show, however, that grain size reduction in the lithosphere leads to relatively strong plate boundaries on the early Earth, which slow slab sinking. During this “sluggish subduction,” sinking plates can heat up enough to melt when the mantle temperature is ≳1600 °C. Crustal melting via sluggish subduction can thus explain TTG formation during the Archean due to elevated mantle temperatures and the paucity of TTG production since due to mantle cooling.
Cardiac troponin concentrations following exercise and the association with cardiovascular disease and outcomes: rationale and design of the prospective TREAT cohort study
Authors: Janssen Sylvan L J E , Lamers Sacha K , Vroemen Wim H M , Denessen Ellen J S , Berge Kristian , Bekers Otto , Hopman Maria T E , Brink Monique , Habets Jesse , Nijveldt Robin , Van Everdingen Wouter M , Aengevaeren Vincent L , Mingels Alma M A , Eijsvogels Thijs M H 
Published: June 2024

Exercise can produce transient elevations of cardiac troponin (cTn) concentrations, which may resemble the cTn release profile of myocardial infarction. Consequently, clinical interpretation of postexercise cTn elevations (ie, values above the 99th percentile upper reference limit) remains challenging and may cause clinical confusion. Therefore, insight into the physiological versus pathological nature of postexercise cTn concentrations is warranted. We aim to (1) establish resting and postexercise reference values for recreational athletes engaged in walking, cycling or running exercise; (2) compare the prevalence of (sub)clinical coronary artery disease in athletes with high versus low postexercise cTn concentrations and (3) determine the association between postexercise cTn concentrations and the incidence of major adverse cardiovascular events (MACE) and mortality during long-term follow-up. For this purpose, the prospective TRoponin concentrations following Exercise and the Association with cardiovascular ouTcomes (TREAT) observational cohort study was designed to recruit 1500 recreational athletes aged ≥40 to <70 years who will participate in Dutch walking, cycling and running events. Baseline and postexercise high-sensitivity cTnT and cTnI concentrations will be determined. The prevalence and magnitude of coronary atherosclerosis on computed tomography (eg, coronary artery calcium score, plaque type, stenosis degree and CT-derived fractional flow reserve) will be compared between n=100 athletes with high postexercise cTn concentrations vs n=50 age-matched, sex-matched and sport type-matched athletes with low postexercise cTn concentrations. The incidence of MACE and mortality will be assessed in the entire cohort up to 20 years follow-up. The TREAT study will advance our understanding of the clinical significance of exercise-induced cTn elevations in middle-aged and older recreational athletes.Trial registration numberNCT06295081.
HDL-cholesterol confers sensitivity of immunotherapy in nasopharyngeal carcinoma via remodeling tumor-associated macrophages towards the M1 phenotype
Authors: Luo Fan , Cao Jiaxin , Chen Qun , Liu Lusha , Yang Ting , Bai Xue , Ma Wenjuan , Lin Chaozhuo , Zhou Ting , Zhan Jianhua , Huang Yan , Yang Yunpeng , Zhao Hongyun , Zhang Li 
Published: June 2024

BackgroundThe sustained effectiveness of anti-programmed cell death protein-1/programmed death-ligand 1 treatment is limited to a subgroup of patients with advanced nasopharyngeal carcinoma (NPC), and the specific biomarker determining the response to immunotherapy in NPC remains uncertain.MethodsWe assessed the associations between pre-immunotherapy and post-immunotherapy serum lipoproteins and survival in a training cohort (N=160) and corroborated these findings in a validation cohort (N=100). Animal studies were performed to explore the underlying mechanisms. Additionally, the relationship between high-density lipoprotein-cholesterol (HDL-C) levels and M1/M2-like macrophages, as well as activated CD8+T cells in tumor tissues from patients with NPC who received immunotherapy, was investigated.ResultsThe lipoproteins cholesterol, HDL-C, low-density lipoprotein-cholesterol, triglycerides, apolipoprotein A-1 (ApoA1), and apolipoprotein B, were significantly altered after immunotherapy. Patients with higher baseline HDL-C or ApoA1, or those with increased HDL-C or ApoA1 after immunotherapy had longer progression-free survival, a finding verified in the validation cohort (p<0.05). Multivariate analysis revealed that baseline HDL-C and elevated HDL-C post-immunotherapy were independent predictors of superior PFS (p<0.05). Furthermore, we discovered that L-4F, an ApoA1 mimetic, could inhibit tumor growth in NPC xenografts. This effect was associated with L-4F’s ability to polarize M2-like macrophages towards an M1-like phenotype via the activation of mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) p65, thereby alleviating immunosuppression in the tumor microenvironment. Importantly, in patients with NPC with high plasma HDL-C levels, the number of M2-like macrophages was significantly decreased, while M1-like macrophages and activated CD8+T cells were notably increased in those with high HDL-C levels.ConclusionHigher baseline HDL-C levels or an increase in HDL-C post-immunotherapy can enhance immunotherapeutic responses in patients with NPC by reprogramming M2-like macrophages towards the M1 phenotype. This suggests a potential role for prospectively exploring ApoA1 mimetics as adjuvant agents in combination with immunotherapy.
Intracellular Osteopontin Promotes the Release of TNFα by Mast Cells to Restrain Neuroendocrine Prostate Cancer
Authors: Sulsenti Roberta , Scialpi Giuseppina B. , Frossi Barbara , Botti Laura , Ferri Renata , Tripodi Irene , Piva Annamaria , Sangaletti Sabina , Pernici Davide , Cancila Valeria , Romeo Francesco , Chiodoni Claudia , Lecis Daniele , Bianchi Francesca , Fischetti Irene , Enriquez Claudia , Crivelli Filippo , Bregni Marco , Renne Giuseppe , Pece Salvatore , Tripodo Claudio , Pucillo Carlo E. , Colombo Mario P. , Jachetti Elena 
Published: June 2024

Abstract
Neuroendocrine prostate cancer (NEPC) is an aggressive form of prostate cancer that emerges as tumors become resistant to hormone therapies or, rarely, arises de novo in treatment-naïve patients. The urgent need for effective therapies against NEPC is hampered by the limited knowledge of the biology governing this lethal disease. Based on our prior observations in the transgenic adenocarcinoma of the mouse prostate (TRAMP) spontaneous prostate cancer model, in which the genetic depletion of either mast cells (MC) or the matricellular protein osteopontin (OPN) increases NEPC frequency, we tested the hypothesis that MCs can restrain NEPC through OPN production, using in vitro co-cultures between murine or human tumor cell lines and MCs, and in vivo experiments. We unveiled a role for the intracellular isoform of OPN, so far neglected compared with the secreted isoform. Mechanistically, we unraveled that the intracellular isoform of OPN promotes TNFα production in MCs via the TLR2/TLR4-MyD88 axis, specifically triggered by the encounter with NEPC cells. We found that MC-derived TNFα, in turn, hampered the growth of NEPC. We then identified the protein syndecan-1 (SDC1) as the NEPC-specific TLR2/TLR4 ligand that triggered this pathway. Interrogating published single-cell RNA-sequencing data, we validated this mechanism in a different mouse model. Translational relevance of the results was provided by in silico analyses of available human NEPC datasets and by immunofluorescence on patient-derived adenocarcinoma and NEPC lesions. Overall, our results show that MCs actively inhibit NEPC, paving the way for innovative MC-based therapies for this fatal tumor. We also highlight SDC1 as a potential biomarker for incipient NEPC.
UK rider reported falls in a 12-month period: circumstances and consequences
Authors: Marlin D.J. , Williams J.M. 
Published: June 2024

Abstract
Anecdotally, horse-riding is a ‘dangerous sport’, often grouped with activities such as motorcycling, skiing, parachuting, bull-riding, and rugby. This opinion is increasingly supported by evidence from retrospective analysis of trauma centre admissions for equestrian related incidents (ERI’s), albeit from relatively low numbers. The most common approach to reducing severity of ERI’s has focussed on encouraging the wearing of riding helmets and to a lesser extent, air-jackets and or body-protectors. Horse riders in the UK were surveyed to ascertain their experience of falls while riding in the preceding 12 months. A total of 3,757 responses were received with a subset of 1,977 complete surveys analysed. The majority of respondents were female (97%, n = 1,914). Falling off once in the last 12 months was most common (53.4%; n = 1,055); 24.2% (n = 478) had fallen off twice, 11.4% (n = 225) three times and 6.5% (n = 129) more than 5 times. Respondents were asked to specify the activity they were undertaking when their last fall occurred; hacking/trail riding (25.9%; n = 513), schooling on the flat (25.8%; n = 511) and showjumping schooling (19.4%; n = 384) were the three most common activities where falls took place. Horses changing direction rapidly (40.9%; n = 808) or rearing/bucking (23.8%; n = 470) were the most common reasons for rider falls, with most (73%; n = 1,443) riders falling off the side of the horse. Riders were most likely to injure their back (51%; n = 1,008), shoulders (39%; n = 771) or pelvis (37%; n = 731) when they fell off, but most injuries were self-rated as minor. Severe injuries as a result of a fall were more common when the riders’ head, back, shoulder or ankle was injured. A variety of factors appear to be involved in rider falls from horses, and many of these may be modifiable and hence preventable.