bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of Clay in an EVA-Based Intumescent Formulation. Comparison with the Intumescent Formulation Using Polyamide-6 Clay Nanocomposite As Carbonisation Agent
Authors: Dabrowski FrançOis , Le Bras Michel , Cartier Laurent , Bourbigot Serge 
Published: August 2002

This work deals with the use of clay as a filler in an intumescent EVA-based formulation using a charring polymer (polyamide-6) as a carbonization agent. Using PA-6 clay nanocomposite instead of pure PA-6 had been shown to improve the fire properties of the intumescent blend. In this study, using clay as a “classical” filler enabled the same level of FR performance to be obtained in the first step of the combustion as when directly using exfoliated clay in PA-6. But in the second half of the combustion, the clay destabilizes the system and increases the flammability. Moreover, a kinetic modeling of the degradation of the EVA-based formulations shows that adding clay to the blend enables the same mode of degradation and the same invariant parameters as for the polyamide-6 clay nanocomposite containing intumescent blend. It is assumed that these kinetic data can be correlated with the improvement of the fire performance in the first step of combustion as observed under the cone calorimeter. The increase in the flammability by the K-10 in the second half of the combustion shows the advantages of using nanoclay rather than micronclay in an intumescent system.
Time Response of Shape Memory Alloy Actuators
Authors: Potapov Pavel L. , Da Silva Edson P. 
Published: August 2002

Force/displacement actuators with the high output power and time response can be fabricated from shape memory wires or ribbons. Typically Ni-Ti shape memory alloys are used as an active material in such actuators. They are driven by Joule heating and air convection cooling. In the present work, the time response of various types of Ni-Ti actuators having different transformation temperatures and geometrical sizes, is studied systematically under conditions of free and forced air convection. The simple analytical model for calculating the time response is developed which accounts for the latent heat and thermal hysteresis of transformation. For all the types of considered actuators, the calculated time response is in a good agreement with that observed experimentally. Finally, on the base of the suggested model, we present the time response of Ni-Ti actuators calculated as a function of their transformation temperature and cross section dimensions.
VIRTUAL KNOT GROUPS AND THEIR PERIPHERAL STRUCTURE
Authors: KIM SE-GOO 
Published: August 2002

Virtual knots, defined by Kauffman, provide a natural generalization of classical knots. Most invariants of knots extend in a natural way to give invariants of virtual knots. In this paper we study the fundamental groups of virtual knots and observe several new and unexpected phenomena. In the classical setting, if the longitude of a knot is trivial in the knot group then the group is infinite cyclic. We show that for any classical knot group there is a virtual knot with that group and trivial longitude. It is well known that the second homology of a classical knot group is trivial. We provide counterexamples of this for virtual knots. For an arbitrary group G, we give necessary and sufficient conditions for the existence of a virtual knot group that maps onto G with specified behavior on the peripheral subgroup. These conditions simplify those that arise in the classical setting.
The African‐specific CYP2D6*17 allele encodes an enzyme with changed substrate specificity
Authors: Wennerholm Agneta , Dandara Collet , Sayi Jane , Svensson Jan‐Olov , Abdi Yakoub Aden , Ingelman‐Sundberg Magnus , Bertilsson Leif , Hasler Julia , Gustafsson Lars L. 
Published: August 2002

ObjectiveThe effects of the CYP2D6*17 and *29 alleles on substrate specificity and enzyme activity were studied by correlating CYP2D6 genotype to phenotype with 4 probe drugs (codeine, debrisoquine, dextromethorphan, metoprolol) in black Tanzanians and white Swedes.MethodsThe black Tanzanian subjects represented the following 6 genotypic groups: A, (CYP2D6*1 or *2)/(*1 or *2) (n = 13); B, CYP2D6*17/*17 (n = 5); C, CYP2D6*29/*29 (n = 4); D, CYP2D6*1/*17 (n = 5); E, CYP2D6*5/*17 (n = 4); and F, various genotypes (n = 4). The white subjects were from 4 groups, as follows: A, (CYP2D6*1 or *2)/(*1 or *2) (n = 7); B, (CYP2D6*1 or *2)/(*3, *4, or *5) (n = 7); C, homozygous for defect alleles (n = 7); and D, duplicated CYP2D6 gene (n = 2).ResultsThe metabolic ratios of the 4 probe drugs correlated significantly (rs = 0.69–0.92; P < .001) in both populations. Tanzanian subjects homozygous for the CYP2D6*17 allele were slower metabolizers when debrisoquine or dextromethorphan was used as the probe drug than when codeine or metoprolol was used, showing a different substrate specificity of CYP2D6.17 than of CYP2D6.1 and CYP2D6.2. This was confirmed with analysis of covariance of the different metabolic ratios for a subgroup of subjects carrying only the CYP2D6*17 mutated allele (n = 9) compared with all other subjects (n = 44). The metabolic ratios of dextromethorphan and metoprolol differed significantly among Tanzanian subjects homozygous for the CYP2D6*29 allele compared with those with CYP2D6*1 or *2 alleles.ConclusionWe found differences in the disposition of 4 CYP2D6 probe drugs in black Tanzanians compared with Swedes. The differences were caused by the presence of CYP2D6.17 and CYP2D6.29. The results show that CYP2D6.17 exhibits altered substrate specificity compared with CYP2D6.1 and CYP2D6.2.Clinical Pharmacology & Therapeutics (2002) 71, 77–88; doi: 10.1067/mcp.2002.120239
Comparative angiotensin II receptor blockade in healthy volunteers: The importance of dosing
Authors: Maillard Marc P. , Würzner Grégoire , Nussberger Jürg , Centeno Catherine , Burnier Michel , Brunner Hans R. 
Published: August 2002

ObjectivesWe have reported previously that 80 mg valsartan and 50 mg losartan provide less receptor blockade than 150 mg irbesartan in normotensive subjects. In this study we investigated the importance of drug dosing in mediating these differences by comparing the AT1‐receptor blockade induced by 3 doses of valsartan with that obtained with 3 other antagonists at given doses.MethodsValsartan (80, 160, and 320 mg), 50 mg losartan, 150 mg irbesartan, and 8 mg candesartan were administered to 24 healthy subjects in a randomized, open‐label, 3‐period crossover study. All doses were given once daily for 8 days. The angiotensin II receptor blockade was assessed with two techniques, the reactive rise in plasma renin activity and an in vitro radioreceptor binding assay that quantified the displacement of angiotensin II by the blocking agents. Measurements were obtained before and 4 and 24 hours after drug intake on days 1 and 8.ResultsAt 4 and 24 hours, valsartan induced a dose‐dependent “blockade” of AT1 receptors. Compared with other antagonists, 80 mg valsartan and 50 mg losartan had a comparable profile. The 160‐mg and 320‐mg doses of valsartan blocked AT1 receptors at 4 hours by 80%, which was similar to the effect of 150 mg irbesartan. At trough, however, the valsartan‐induced blockade was slightly less than that obtained with irbesartan. With use of plasma renin activity as a marker of receptor blockade, on day 8, 160 mg valsartan was equivalent to 150 mg irbesartan and 8 mg candesartan.ConclusionsThese results show that the differences in angiotensin II receptor blockade observed with the various AT1 antagonists are explained mainly by differences in dosing. When 160‐mg or 320‐mg doses were investigated, the effects of valsartan hardly differed from those obtained with recommended doses of irbesartan and candesartan.Clinical Pharmacology & Therapeutics (2002) 71, 68–76; doi: 10.1067/mcp.2002.121425
Comparison of US Oncologist Rurality by Practice Setting and Patients Served
Authors: Cornelius Sarah L. , Shaefer Andrew P. , Wong Sandra L. , Moen Erika L. 
Published: January 2024

ImportanceStudies of the oncology workforce most often classify physician rurality by their practice location, but this could miss the true extent of physicians involved in rural cancer care.ObjectiveTo compare a method for identifying oncology physicians involved in rural cancer care that uses the proportion of rural patients served with the standard method based on practice location.Design, Setting, and ParticipantsThis cross-sectional study used retrospective Centers for Medicare &amp;amp; Medicaid Services encounter data on medical oncologists, radiation oncologists, and surgeons treating Medicare beneficiaries diagnosed with breast, colorectal, or lung cancer from January 1 to December 31, 2019. Data were analyzed from May to September 2023.Main Outcomes and MeasuresThe standard method of classifying oncologist physician rurality based on practice location was compared with a novel method of classification based on proportion of rural patients served.ResultsThe study included 27 870 oncology physicians (71.3% male), of whom 835 (3.0%) practiced in a rural location. Physicians practicing in a rural location treated a high proportion of rural patients (median, 50.0% [IQR, 16.7%-100%]). When considering the rurality of physicians’ patient panels, 5123 physicians (18.4%) whose patient panel included at least 20% rural patients, 3199 (11.5%) with at least 33% rural patients, and 1996 (7.2%) with at least 50% rural patients were identified. Using a physician’s patient panel to classify physician rurality revealed a higher number and greater spread of oncology physicians involved in rural cancer care in the US than the standard method, while maintaining high performance (area under the curve, 0.857) and fair concordance (κ, 0.346; 95% CI, 0.323-0.369) with the method based on practice setting.Conclusions and RelevanceIn this cross-sectional study, classifying oncologist rurality by the proportion of rural patients served identified more oncology physicians treating patients living in rural areas than the standard method of practice location and may more accurately capture the rural cancer physician workforce, as many hospitals have historically been located in more urban areas. This new method may be used to improve future studies of rural cancer care delivery.
In Utero Exposure to Alcohol and Tobacco and Electroencephalogram Power During Childhood
Authors: Pini Nicolò , Sania Ayesha , Rao Shreya , Shuffrey Lauren C. , Nugent J. David , Lucchini Maristella , McSweeney Marco , Hockett Christine , Morales Santiago , Yoder Lydia , Ziegler Katherine , Perzanowski Matthew S. , Fox Nathan A. , Elliott Amy J. , Myers Michael M. , Fifer William P. 
Published: January 2024

ImportancePrenatal alcohol exposure (PAE) and prenatal tobacco exposure (PTE) are risk factors associated with adverse neurobehavioral and cognitive outcomes.ObjectiveTo quantify long-term associations of PAE and PTE with brain activity in early and middle childhood via electroencephalography (EEG).Design, Setting, and ParticipantsThis cohort study included participants enrolled in the Safe Passage Study (August 2007 to January 2015), from which a subset of 649 participants were followed up in the Environmental Influences on Child Health Outcomes Program. From September 2018 through November 2022, EEG recordings were obtained at ages 4, 5, 7, 9, or 11 years. Data were analyzed from November 2022 to November 2023.ExposuresMaternal self-reported consumptions of alcohol and tobacco during pregnancy were captured at the recruitment interview and at up to 3 visits during pregnancy (20-24, 28-32, and ≥34 weeks’ gestation). Classifications of PAE (continuous drinking, quit-early drinking, and nondrinking) and PTE (continuous smoking, quit-early smoking, and nonsmoking) were previously obtained.Main Outcomes and MeasuresEEG band powers (theta, alpha, beta, gamma) were extracted from the EEG recordings. Linear regression models were used to estimate the associations of PAE and PTE with EEG estimates.ResultsThe final sample included 649 participants (333 [51.3%] female) aged 4, 5, 7, 9, or 11 years. Children whose mothers were in the quit-early drinking cluster had increased alpha power (0.116 [95% CI, 0.023 to 0.209] μV2; P = .02) compared with individuals without PAE. The magnitude of this increase was approximately double for children exposed to continuous drinking (0.211 [95% CI, 0.005 to 0.417] μV2; P = .04). Children whose mothers were in the continuous smoking cluster had decreased beta power (−0.031 [95% CI, −0.059 to −0.003] μV2; P = .03) and gamma power (−0.020 [95% CI, −0.039 to −0.000] μV2; P = .04) compared with the nonsmoking cluster. In exploratory sex-stratified models, male participants in the quit-early PAE cluster had greater EEG power in the alpha band (0.159 [95% CI, 0.003 to 0.315] μV2; P = .04) compared with those with no PAE, and the difference was approximately double for male participants with continuous PAE (0.354 [95% CI, 0.041 to 0.667] μV2; P = .03). Male participants in the continuous PTE cluster had decreased beta (−0.048 [95% CI, −0.090 to − 0.007] μV2; P = .02) and gamma (−0.032 [95% CI, −0.061 − 0.002] μV2; P = .04) power compared with those with no PTE.Conclusions and RelevanceThese findings suggest that even low levels of PAE and PTE were associated with long-term alterations of brain activity.
Xylazine in Overdose Deaths and Forensic Drug Reports in US States, 2019-2022
Authors: Cano Manuel , Daniulaityte Raminta , Marsiglia Flavio 
Published: January 2024

ImportanceXylazine is increasingly reported in street drugs and fatal overdoses in the US, yet state-level data are limited, hampering local public health responses.ObjectiveTo gather available state-level data on xylazine involvement in overdose deaths and in forensic drug reports.Design, Setting, and ParticipantsThis cross-sectional study was a secondary analysis of 2019 to 2022 data from the National Forensic Laboratory Information System (NFLIS), National Center for Health Statistics, and individual states' medical examiner or public health agency reports. Data were analyzed from August to October 2023.ExposureState.Main Outcomes and MeasuresYearly xylazine-related overdose deaths per 100 000 residents; xylazine NFLIS drug reports, both per 100 000 residents and as a percentage of all NFLIS drug reports (from samples of drugs seized by law enforcement and analyzed by NFLIS-participating laboratories).ResultsA total of 63 state-years were included in analyses of mortality rates, while 204 state-years were included in analyses of NFLIS reports. According to the publicly available data compiled in this study, at least 43 states reported at least 1 xylazine-related overdose death from 2019 to 2022, yet yearly totals of xylazine-related deaths were available for only 21 states. Of states with data available, xylazine-involved overdose death rates were highest in Vermont (10.5 per 100 000 residents) and Connecticut (9.8 per 100 000 residents) in 2022. In 2019, 16 states had zero xylazine reports included in NFLIS reports; in 2022, only 2 states had zero xylazine reports and all but 3 states had recorded an increase in xylazine’s representation in NFLIS reports. In 2022, xylazine represented 16.17% of all NFLIS reports in Delaware and between 5.95% and 7.00% of NFLIS reports in Connecticut, Maryland, District of Columbia, New Jersey, and Rhode Island, yet less than 1.0% of NFLIS reports in 35 different states.Conclusions and RelevanceIn this cross-sectional study of publicly available data on fatal overdoses and drugs analyzed by forensic laboratories, xylazine’s reported presence in overdose deaths and forensic reports was concentrated in the eastern US yet extended across the country to encompass nearly all states. In spite of xylazine’s geographic reach, yearly state-level numbers of xylazine-related overdose deaths were publicly available for less than half of all states.
Electrical Tracking of the Mott Insulating Kitaev Magnet using Graphene/α‐RuCl3 Heterostructure
Authors: Chau Tuan Khanh , Choi Youngsu , Hwang Kyusung , Oh Gyounghoon , Akhtar Sophia , Kim Jeongyong , Choi Kwang‐Yong , Lee Hyun‐Yong , Hong Sung Ju , Suh Dongseok 
Published: January 2024

AbstractElectrical signatures for quantum magnetic phases of α‐RuCl3 sensed by an adjacent graphene field‐effect transistor (FET) are reported. The gate‐voltage dependence of the graphene FET reveals p‐type doping beneath α‐RuCl3 caused by the charge transfer due to the work function difference. Furthermore, the gate‐voltage hysteresis exhibits a marked change in the transport behavior with the temperature variation. The high‐T simple paramagnetic phase and the low‐T zigzag antiferromagnetic phase of α‐RuCl3 exhibit negligible hysteresis. In sharp contrast, a huge hysteresis of the graphene FET at intermediate temperatures is observed. The possibility that the observed conductance hysteresis is associated with the intriguing continuum excitations of the thermally induced Kitaev paramagnet state is discussed. The results show that the proximity effect‐based electric approach can be utilized for investigating charge‐neutral quasiparticles in quantum magnetic insulators.
Single‐Atom Nanozymes for Catalytic Therapy: Recent Advances and Challenges
Authors: He Weiyi , Wu Jiahao , Liu Jianli , Li Jing 
Published: January 2024

AbstractAs a powerful tool, nanozyme catalysts broaden the avenues to implement bio‐inspired solutions for addressing many important concerns, covering energy, healthcare, the environment, and more. Recent endeavors, characterized by atomic precision, have enabled extensive exploration of single‐atom nanozymes (SAzymes) with high catalytic activity, superior substrate selectivity, and integrated multifunctionalities, thus becoming an emerging field that bridges nanotechnology and biology. This review provides a brief outline of the progress and summarizes the latest research advances regarding SAzymes in biomedical therapeutics, mainly including tumor therapy, wound antibacterial therapy, and tissue anti‐inflammatory therapy, with a focus on their prototypical synthesis and therapeutic catalytic mechanisms. Finally, current challenges and future perspectives for the engineering of advanced SAzymes are also discussed and outlooked. It is anticipated that this review of the important area shall provide useful guidance for catalytic therapy.
Chemical/Electrochemical Dual‐Driven Transition Behavior of Copper Element from Current Collector to Chalcogenide Anode in Sodium‐Ion Batteries
Authors: Yin Xucai , Liu Yuejun , Ren Yang , Zhou Yulin , Cheng Xinqun , Chen Meng , Du Chunyu , Yin Gepin , Huo Hua 
Published: January 2024

AbstractThe transition phenomenon involving copper replacing the transition metal elements within transition metal chalcogenides (TMCs) is a recent and unique observation in the context of sodium ion batteries (SIBs) where TMCs serve as anodes. Fundamental understanding of the driving forces and kinetics governing this transition is crucial for elucidating the sodium storage mechanism in TMCs anodes. Herein, cobalt disulfide (CoS2) has been chosen as a representative anode. It is revealed that the transition behavior of copper replacing cobalt during the cycling originates from chemical/electrochemical dual‐driving forces. The chemical driving force emanates from the interaction between Cu+ dissolved in the electrolyte and the resulting sodium polysulfide products. The reaction extent is intricately linked to the surface roughness of the copper collector. The electrochemistrical driving force is effectively elucidated through the application of the Hard‐Soft‐Acid‐Base theory. Multiple charaterization techniques, such as Solid‐state nuclear magnetic resonance (ssNMR) have been employed to confirm that cobalt exists as cation instead of metal after transition. This research offers a novel perspective understanding the transition behavior exhibited by CoS2, with potential wider implications for understanding analogous behaviors in other metal sulfide anodes.
A Continuous Pressure Positioning Sensor with Flexible Multilayer Structures Based on a Combinatorial Bionic Strategy
Authors: Meng Xiancun , Zhang Changchao , Xie Haoran , Niu Shichao , Han Zhiwu , Ren Luquan 
Published: January 2024

AbstractA high‐performance flexible pressure sensor is one of the most important components of electronic skin, which can endow artificial devices with human‐like capabilities. However, the electronic skin usually relies on the arrays of sensors to simultaneously obtain both pressure magnitude and position, making the data processing time‐consuming, tedious, and error‐prone. Here, a novel continuous pressure positioning sensor (PPS) with flexible multilayer structures based on a combinatorial bionic strategy is designed and fabricated. This PPS is composed of the pressure sensing layer (PSL) and the pressure positioning layer (PPL). The PSL exhibits high sensitivity (18.87 kPa−1) owing to the bionic crack structures. Based on the connection/disconnection of the upper and lower conductive layers, this PPL exhibits excellent positioning properties with excellent resolution (≈35 µm). More importantly, due to stable signal change and synchronization of signals between the two functional layers (>21 pa), this PPS can recognize the type of signal. Applications of the PPS for pressure monitoring, tire safety monitoring, lunar rover road condition monitoring, and emotional communication in human–computer interaction are further demonstrated to measure magnitude, position, and recognition of pressure signals. So, it will have broad application prospects in fields such as pressure detection and human–computer interaction.
3D‐Printed Architectured Silicones with Autonomic Self‐Healing and Creep‐Resistant Behavior
Authors: Menasce Stefano , Libanori Rafael , Coulter Fergal Brian , Studart André R. 
Published: January 2024

AbstractSelf‐healing silicones that are able to restore functionalities and extend the lifetime of soft devices hold great potential in many applications. However, currently available silicones need to be triggered to self‐heal or suffer from creep‐induced irreversible deformation during use. Here, a platform is proposed to design and print silicone objects that are programmed at the molecular and architecture levels to achieve self‐healing at room temperature while simultaneously resisting creep. At the molecular scale, dioxaborolanes moieties are incorporated into silicones to synthesize self‐healing vitrimers, whereas conventional covalent bonds are exploited to make creep‐resistant elastomers. When combined into architectured printed parts at a coarser length scale, the layered materials exhibit fast healing at room temperature without compromising the elastic recovery obtained from covalent polymer networks. A patient‐specific vascular phantom and fluidic chambers are printed to demonstrate the potential of architectured silicones in creating damage‐resilient functional devices using molecularly designed elastomer materials.