bluuebunny/crossref_metadata_2025_split huggingface dataset:
MR imaging of proton beam‐induced oxygen depletion
Authors: Schieferecke Juliane , Hoffmann Aswin , Pawelke Jörg 
Published: January 2025

AbstractBackgroundPrevious studies have shown that in‐beam magnetic resonance imaging (MRI) can be used to visualize a proton beam during the irradiation of liquid‐filled phantoms. The beam energy‐ and current‐dependent local image contrast observed in water was identified to be predominantly caused by beam‐induced buoyant convection and associated flow effects. Besides this flow dependency, the MR signal change was found to be characterized by a change in the relaxation time of water, hinting at a radiochemical contribution, which was hypothesized to lie in oxygen depletion‐evoked relaxation time lengthening. The elucidation of the underlying contrast mechanism is required to enable the further assessment of the application potential of MRI‐based proton beam visualization in tissue.PurposeThe underlying radiochemical cause of the observed local beam‐induced change in the relaxation time of water should be identified in beam visualization experiments testing the hypothesis of beam‐induced oxygen depletion‐evoked relaxation time lengthening.MethodsCombined irradiation and imaging experiments were performed using static proton pencil beam irradiation, background‐nulled inversion recovery (IR) MRI and a range of flow‐restricted phantoms differing in initial oxygen concentration and homogeneity. The similarity of the irradiation‐induced MRI contrast to the proton pencil beam dose distribution acquired on radiochromic film, the expected dose dependence and temporal stability, the TR dependence as well as the dependence on the initial oxygen concentration and the oxygen consumption rate were tested. Moreover, the feasibility of oxygen depletion‐based beam visualization in tissue‐mimicking phantoms was assessed. The levels of irradiation‐induced oxygen depletion and relaxation time lengthening were estimated based on the measured temperatures and initial oxygen concentrations of the phantoms, the experimentally determined inversion times required for phantom background signal nulling and dosimetric measurements.ResultsThe proton irradiation‐induced contrast in background‐nulled IR images of well oxygenated phantoms was found similar to the proton pencil beam dose distribution and showed the characteristics expected for oxygen depletion‐induced MRI contrast. No beam‐induced contrast was observed in the poorly oxygenated, inhomogeneous tissue‐mimicking phantoms.ConclusionsProton beam‐induced radiochemical oxygen depletion can be visualized using relaxation time contrast‐based IR MRI and represents the first identified flow‐independent contrast mechanism in MRI‐based proton beam visualization in real‐time. Beam detection in tissue, however, will be complicated by the increased relaxation time inhomogeneity and the lowered levels of initial oxygen concentration compared to in liquids at atmospheric equilibrium and requires further assessment.
Optimization of x‐ray dark‐field CT for human‐scale lung imaging
Authors: Guo Peiyuan , Spindler Simon , Rawlik Michal , Lu Jincheng , Men Longchao , Hong Mingzhi , Stampanoni Marco , Yin Hongxia , Xu Yan , Wang Zhenchang , Zhang Li , Wang Zhentian 
Published: January 2025

AbstractBackgroundX‐ray grating‐based dark‐field imaging can sense the small angle scattering caused by object's micro‐structures. This technique is sensitive to the porous microstructure of lung alveoli and has the potential to detect lung diseases at an early stage. Up to now, a human‐scale dark‐field CT (DF‐CT) prototype has been built for lung imaging.PurposeThis study aimed to develop a thorough optimization method for human‐scale dark‐field lung CT and guide the system design.MethodsWe introduced a task‐based metric formulated as the contrast‐to‐noise ratio (CNR) between normal and lesioned alveoli for system parameter optimization and designed a digital human‐thorax phantom to fit the task of lung disease detection. Furthermore, a computational framework was developed to model the signal propagation in DF‐CT and established the link between system parameters and the CNR metric.ResultsWe showed that for a DF‐CT system, its CNR first increases and then decreases with the system auto‐correlation length (ACL). The optimal ACL is mostly independent of system's visibility, and is only related to the phantom's properties, that is, its size and absorption. For our phantom, the optimal ACL is about 0.35 µm at the design energy of 60 keV. As for system geometry, increasing source‐detector and isocenter‐detector distance can extend the system's maximal ACL, making it easier for the system to meet the optimal ACL and relaxing the grating pitches. We proposed a set of parameters for a projective fringe system that can satisfy the simulated optimal ACL.ConclusionThis study introduced a task‐based metric and a process for DF‐CT optimization. We demonstrated that for a given phantom, the detection performance of the system is optimized at a specific ACL. The optimization method and design principles are independent from the underlying dark‐field imaging method and can be applied to DF‐CT system design using different grating‐based implementations such as Talbot‐Lau interferometer (TLI) or projective fringe method.
Solving Large‐Scale Weapon Target Assignment Problems in Seconds Using Branch‐Price‐And‐Cut
Authors: Bertsimas Dimitris , Paskov Alex 
Published: January 2025

ABSTRACTThis paper proposes a framework based on branch‐price‐and‐cut to solve the weapon target assignment (WTA) problem, a popular class of non‐linear assignment problems that has received significant attention over the past several decades. We first reformulate the WTA into a form amenable to column generation and then derive efficient algorithms for initializing the column generation, solving the pricing problem, generating clique cuts, and managing the branch‐and‐bound. Through significant experimentation, we display the framework's efficiency – which scales to solve problems with 10000 targets and weapons on a laptop and exactly solves problems in seconds, which previously took hours to solve. We also discuss extensions to common WTA variants and more general non‐linear assignment problems in hopes of motivating algorithmic developments.
A Machine‐Learning Approach to Understanding Performance of Canadian Nonprofit Sport Organizations
Authors: Yang Yanxiang , Byers Terri , Koenigstorfer Joerg 
Published: January 2025

ABSTRACTPrevious approaches to model the performance of nonprofit organizations and their determinants largely rely on linearity and monotonicity assumptions. This research note makes a methodological contribution by jointly using descriptive and predictive models, particularly advanced machine‐learning algorithms that allow for the consideration of non‐linear or non‐monotonic relationships, to understand the relevance of factors associated with the performance of nonprofit sport clubs as well as the nature of relationships. Data were collected via an online survey with 126 representatives of Canadian sport clubs, in which four performance domains were considered: Member relationship, service quality, financial stability, and sporting success. Explanatory linear regressions and four machine‐learning models (i.e., ridge regression, bagged regression, random forest, and gradient boosting machine) are used. The results reveal that machine‐learning models increase the explanatory power compared to linear models. The random forest outperforms the other models in terms of root mean squared error and, partly, mean absolute error, and R square (even though absolute levels of R square are low at times, particularly for financial stability and sporting success, where the presence or absence of a high‐volume donor or high‐performance sports mission might help or hinder performance). Non‐linear relationships are found for several predictors across the four dimensions that were considered, such as the use of outside knowledge, trust, coopetition, age, and tenure of the club representative. We showcase the use of joint computational techniques in nonprofit research to serve two relevant goals: enhance the explanatory power and maintain the interpretability of predictive models.
Metformin and Cognitive Performance in Patients With Type 2 Diabetes: An Umbrella Review
Authors: Enderami Athena , Shariati Behnam , Zarghami Mehran , Aliasgharian Aily , Ghazaiean Mobin , Darvishi‐Khezri Hadi 
Published: January 2025

ABSTRACTContradictory results for the association between metformin intake and changes in cognitive function have been reported. We attempted to overview systematic reviews and meta‐analyses showing the role of metformin, as mono or combination therapy, in cognitive performance alterations among patients with type 2 diabetes mellitus (T2DM) and to determine the quality of the evidence as well. To find the English‐written reviews, a literature search was conducted on PubMed, Web of Science, Scopus, Cochrane Library, Trip, and Google Scholar by May 1, 2023. The literature search unearthed 2672 records, 10 of which were included in the study. Metformin may provide cognitive benefits for patients with type 2 diabetes, as evidence suggests potential improvements in memory and a reduced risk of neurodegenerative diseases. Even though the Alzheimer's Disease Assessment Scale‐Cognitive Subscale (ADAS‐Cog) score alterations correspond to raising concerns about cognitive decline, Mini‐Mental State Examination (MMSE) and selective reminding test (SRT) score improvements support metformin's role in improving specific cognitive domains. As such, metformin may exert differential impacts on various aspects of cognitive performance in these patients. However, the inconsistency and low quality of current evidence point toward the need for accurate research to elucidate whether metformin's cognitive effects are protective, neutral, or context‐dependent based on patient profiles.
A Systematic Review of Synthetic and Anticancer and Antimicrobial Activity of Quinazoline/Quinazolin‐4‐one Analogues
Authors: Manhas Neha , Kumar Gobind , Dhawan Sanjeev , Makhanya Talent , Singh Parvesh 
Published: January 2025

AbstractQuinazolines/quinazolin‐4‐ones are significant nitrogen‐containing heterocycles that exist in various natural products and synthetic scaffolds with diverse medicinal and pharmacological applications. Researchers across the globe have explored numerous synthetic strategies to develop safer and more potent quinazoline/quinazolinone analogues, particularly for combating cancer and microbial infections. This review systematically examines scholarly efforts toward understanding this scaffold's synthetic pathways and medicinal relevance, emphasizing the role of metal and non‐metal catalysts and other reagents in their synthesis. Additionally, the article discusses selected compounds’ anticancer and antimicrobial properties, with a brief look into their structure‐activity relationships.
Molybdenum sulphide incorporated flexible poly(vinylidene fluoride) nanocomposites for energy harvesting and water remediation by dye degradation via piezocatalysis
Authors: Aishwarya Ananya , Mondal Suvankar , Bhattacharjee Neelanjan , Dasgupta Titas , Bhattacharyya Arup R. 
Published: January 2025

AbstractMolybdenum sulphide (MoS2) was incorporated into poly(vinylidene difluoride) (PVDF) matrix via melt‐mixing followed by solution casting, to prepare PVDF/MoS2 nanocomposite films with varying MoS2 concentration. Piezoelectric properties of PVDF/MoS2 nanocomposites were significantly boosted by incorporation of MoS2 in PVDF by aiding in the formation of polar phase in the PVDF/MoS2 nanocomposites. Formation of electroactive phases in PVDF/MoS2 nanocomposites was analyzed through Fourier transform infrared and Raman spectroscopic analyses, which also highlighted the interactions between MoS2 and PVDF dipoles. A remarkable polar phase content of ~97% was achieved in the PVDF/3 MoS2 nanocomposite (containing 3 wt% MoS2). Dielectric and ferroelectric investigations further supported the enhancement of interfacial polarization in PVDF/MoS2 nanocomposite films. Piezoelectric response of the fabricated devices was subsequently assessed, demonstrating an output voltage of ~96 V generated through human‐hand actuation on the PVDF/3 MoS2 nanocomposite film. Additionally, the fabricated device exhibited a substantial volumetric power density of ~150 μW/cm2 and a current density of ~7.2 μA/cm2. Notably, the optimized PVDF/MoS2 nanocomposite film exhibited significant degradation efficiencies of ~69.7% and ~67.4% in case of Methylene Blue and Rhodamine B dye, respectively. The successful fabrication of a piezocatalytic PVDF/MoS2 nanocomposite film provided valuable insights into the piezoelectric response for the degradation of various dyes.Highlights
Self‐polarized PVDF/MoS2 nanocomposite with high polar phase content (∼97%) has been achieved via melt‐mixing followed by solution casting.
High d33 value of ~72 pm/V was achieved in the PVDF/3 MoS2 nanocomposite.
PVDF/3 MoS2 nanocomposite based piezoelectric nanogenerator can generate an output voltage of ~96 V under 3 N with sensitivity of ~26 V/N.
Power density of ~150 μW/cm2 and current density of ~7.2 μA/cm2 were obtained.
PVDF/3 MoS2 nanocomposite film acted as an effective piezocatalysts for the degradation of organic dye with >69% efficiency.
Chitosan aerogel containing mechanically fibrillated fibroin and its model test for wound dressing
Authors: Tran Ngoc Phan , Okahisa Yoko , Okubayashi Satoko 
Published: January 2025

AbstractThe biopolymer aerogels of silk fibroin and chitosan composites exhibited brilliant properties such as biocompatibility, antibacterial, nontoxicity, and renewability. Silk fibroin nanofibrils (150–300 nm) can be effectively produced via a wet mechanical method. The introduction of fibroin nanofibrils into chitosan aerogels improved their bioactivity in a stimulus environment, mechanical properties, and promoted wound healing. The results of chitosan aerogels with additional fibroin aerogels revealed a high mechanical modulus (>2.5 MPa, at 80% load), high swelling ratio (>400%), and ideal exudate uptake (>100%). The obtained bio‐aerogels could be prospective for medical applications such as biomaterials and wound dressing.Highlights
Green processes to produce 3D chitosan aerogels containing silk fibroin nanofibrils.
Valuable properties of CS aerogels with a small weight range of mechanically fibrillated fibroin.
CS/FNF aerogels exhibited greater absorption and swelling properties than CS aerogel alone.
Sustainable development of hybrid aerogels from surplus gelatin and chitosan for enhancing the dissolution rate of clotrimazole
Authors: Charoenchaitrakool Manop , Youngkum Patcharaporn , Sudsakorn Kandis , Niamnuy Chalida , Prapainainar Paweena , Kaewmanee Saroch 
Published: January 2025

AbstractHybrid aerogels were developed using surplus gelatin from the pharmaceutical industry and chitosan to address gelatin waste and enhance drug solubility. Glutaraldehyde (GA) was used as a cross‐linking agent to establish a porous network within hydrogels, which were solvent‐exchanged with ethanol and freeze‐dried to form aerogels. These aerogels served as carriers for clotrimazole, a poorly water‐soluble antifungal drug. The impact of the volume ratio of GA to the chitosan–gelatin mixture (ranging from 10% to 40% GA) and chitosan‐to‐gelatin ratios (1:1–1:4) on clotrimazole content and dissolution rate was investigated. Aerogels cross‐linked with 20% GA achieved a drug release rate threefold higher than unprocessed clotrimazole at 180 min, with all aerogels outperforming xerogels and raw clotrimazole. XRD and DSC analyses revealed reduced clotrimazole crystallinity, indicating its transition to an amorphous form. Antifungal tests against Trichophyton mentagrophytes ATCC 9533 showed inhibition zones of 83.5 ± 2.1 mm and 82.5 ± 3.5 mm for aerogels with chitosan‐to‐gelatin ratios of 1:1 and 1:4, respectively, comparable to unprocessed clotrimazole (92.5 ± 3.5 mm). This study demonstrates the potential of gelatin waste and chitosan‐based aerogels as sustainable carriers for poorly water‐soluble drugs, advancing pharmaceutical applications and environmental sustainability.Highlights
A hybrid aerogel composed of chitosan and surplus gelatin was fabricated.
GA amount and chitosan‐to‐gelatin ratio impacted drug content and dissolution.
Clotrimazole‐loaded aerogels dissolved faster than the pure drug and xerogels.
The 1:1 and 1:4 chitosan–gelatin aerogels had similar antifungal efficacy.
An In‐Depth Examination of Learning Behaviors in Autistic Middle‐Schoolers Without Intellectual Disability
Authors: Duncan Amie , Evans Abigail , Vaughn Aaron , Tamm Leanne 
Published: January 2025

ABSTRACTAutistic students demonstrate poor academic performance which may be related to challenges in learning behaviors such as organization, planning, study skills, and so forth. Most studies report on summary scores; however, there may be value in understanding specific strengths and challenges to better inform assessment and intervention efforts. The aim was to assess the profile of learning behaviors in autistic students and the impact of an intervention targeting learning behaviors. Participants included 47 autistic middle‐schoolers without intellectual disability. Caregivers and students completed the Learning Behaviors Checklist assessing academic executive functions at pre and post. Item level summary statistics and effect sizes for pre to post were computed. Both caregivers and students reported infrequent use of critical learning behaviors prior to intervention. Following intervention both raters reported improvement, especially for organization strategies and some study strategies; however, there remained room for improvement. Autistic middle‐schoolers demonstrate specific challenges in learning behaviors that may contribute to poorer academic performance and grades. Intervention may improve these behaviors and provide skills that may benefit them in the future (e.g., high school). However, even after intervention, caregivers and students reported infrequent use of important learning behaviors. Booster sessions and intervention refinement may be warranted.
Registration of two extra‐soft soft red winter wheat germplasms carrying the puroindoline genes on chromosome 5A
Authors: Ma Fengyun , Souza Edward , Sturbaum Anne , Baik Byung‐Kee 
Published: January 2025

AbstractKernel hardness is a primary determinant of the milling and end use quality of wheat (Triticum aestivum L.) and is largely genetically controlled by the Pin genes on chromosome 5D in common wheat. Wheat carrying the wild‐type alleles of the Pin genes exhibits softer kernel texture, higher break flour yield, finer flour particle, and lower damaged starch content than wheat carrying one or two mutant alleles of the Pin genes. The USDA‐ARS developed and released two extra‐soft soft red winter (SRW) wheat germplasms, SWQL11‐146‐4 (Reg. no. GP‐1100, PI 706439) and SWQL11‐156‐5 (Reg. no. GP‐1101, PI 706440), by introgression of the Pin genes on chromosome 5A (Pin 5A genes) from a ‘Chinese Spring’ translocation line to SRW wheat cultivars. SWQL11‐146‐4 and SWQL11‐156‐5 were derived from the crosses of OH04‐264‐58*2//T5AmS‐5AS∙5AL R#45/OH04‐264‐58/3/GA 991371‐6E13 and Milton/T5AmS‐5AS∙5AL R#45//3*USG 3555, respectively, and were grown in four different environments and analyzed for grain and milling characteristics and agronomic performance. Kernel hardness values averaged across environments were 0.7–1.4 in extra‐soft wheat germplasms, 15.3–17.4 in their sibling lines without the Pin 5A genes (wild types), and 18.7‐21.3 in recurrent parents. The break flour yields of SWQL11‐146‐4 and SWQL11‐156‐5 were significantly higher than those of the corresponding wild types and parents. SWQL11‐146‐4 had a higher test weight and flour yield than its wild types and parent. The introgression of the Pin 5A genes induced insignificant changes in kernel diameter and weight, grain protein content, and agronomic performance (heading date, plant height, and grain yield). These two extra‐soft wheat germplasms would be valuable genetic resources for improving the milling and end use quality of soft wheat.
Rigidity Analysis of Hydride Tunneling‐Ready States From Secondary Kinetic Isotope Effects and Hammett Correlations: Relating to the Temperature Dependence of Kinetic Isotope Effects
Authors: Bai Mingxuan , Singh Grishma , Lu Yun 
Published: January 2025

ABSTRACTRecent study on the effects of enzyme mutations on the primary kinetic isotope effects (1° KIEs) of H‐tunneling reactions revealed that a more rigid system results in a weaker temperature dependence of KIEs, indicated by a smaller isotopic activation energy difference (∆Ea = EaD − EaH). In literature, a more rigid system has been defined by the presence of shorter, more densely populated hydrogen donor‐acceptor distances (DADs) in both the productive reactant complexes (PRCs) and the tunneling‐ready states (TRSs). Studying the relationship between DADPRC/DADTRS and ∆Ea can help validate existing H‐tunneling models or guide the development of new theories. In a previous publication, we employed Hammett correlations on hydride acceptors (NAD+ analogues) to propose TRS electronic structures for qualitative analysis of DADTRS order. In this paper, we selected a pair of such systems and used secondary (2°) KIEs on the hydride donor (NADH analogue) to obtain quantitative DADTRS information at the molecular level. TRS structures were computed, and the corresponding 2° KIEs were calculated and fitted to the observed values to extract DADTRS data. PRC structures were also computed. The DADPRC/DADTRS information aligns with the rigidity order derived from Hammett correlation analysis, and the correlation between DADPRC/DADTRS and ∆Ea is consistent with observations in enzyme systems.
Investigation into the effect of phenylalanine gating on anaerobic haem breakdown using the energy landscape approach
Authors: Keith Alasdair D. , Sawyer Elizabeth B. , Choy Desmond C. Y. , Cole James L. , Shang Cheng , Biggs George S. , Klein Oskar James , Brear Paul D. , Wales David J. , Barker Paul D. 
Published: January 2025

AbstractWe have recently demonstrated a novel anaerobic NADH‐dependent haem breakdown reaction, which is carried out by a range of haemoproteins. The Yersinia enterocolitica protein, HemS, is the focus of further research presented in the current paper. Using conventional experimental methods, bioinformatics, and energy landscape theory (ELT), we provide new insight into the mechanism of the novel breakdown process. Of particular interest is the behavior of a double phenylalanine gate, which opens and closes according to the relative situations of haem and NADH within the protein pocket. This behavior suggests that the double phe‐gate fulfills a regulatory role within the pocket, controlling the access of NADH to haem. Additionally, stopped‐flow spectroscopy results provide kinetic comparisons between the wild‐type and the selected mutants. We also present a fully resolved crystal structure for the F104AF199A HemS monomer, including its extensive loop, the first such structure to be completely resolved for HemS or any of its close homologues. The energy landscapes approach provided key information regarding the gating strategy employed by HemS, compensating for current limitations with conventional biophysical and molecular dynamics approaches. We propose that ELT become more widely used in the field, particularly in the investigation of the dynamics and interactions of weak‐binding ligands, and for gating features, within protein cavities.