bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Elevated Temperature Mechanical Properties of Intermetallic Compounds in the Cu–Sn System Using Nanoindentation
Authors: Yin Zuozhu , Sun Fenglian , Guo Mengjiao 
Published: January 2020

Abstract
In electronic packaging, most researchers are mainly focused on the mechanical properties of Cu–Sn intermetallic compounds (IMCs) at room temperature; few studies have looked into the relationship between hardness, elastic modulus, and plasticity of IMCs and elevated temperature. The hardness, elastic modulus, and plasticity of Cu6Sn5 and Cu3Sn at 25–200 °C are investigated by the nanoindentation method. The results show that the hardnesses of Cu6Sn5 and Cu3Sn obey linear attenuation law with elevated temperature. The hardness of Cu6Sn5 is more sensitive to temperature than that of Cu3Sn. This is due to the fact that the melting point of Cu6Sn5 (415 °C) is lower than that of Cu3Sn (670 °C), Cu6Sn5 has a lower normalization temperature than that of Cu3Sn. The elastic modulus of Cu6Sn5 and Cu3Sn and temperature have a parabolic law at 25–200 °C. The elastic modulus of Cu6Sn5 is more sensitive to temperature. This is attributed to the fact that the lattice structure of Cu6Sn5 is changed from hexagonal lattice to monoclinic lattice, causing its volume to expand, thereby making it more sensitive to temperature. The plasticity factors of Cu6Sn5 and Cu3Sn meet the polynomial relationship with elevated temperature. The plasticity factors of Cu6Sn5 and Cu3Sn increase with increasing temperature, which will reduce the resistance to plastic deformation. This is attributed to the fact that the vacancy generated into the material is conducive to the dislocation movement, the dislocation movement will be more active so that the plasticity factors of Cu6Sn5 and Cu3Sn gradually increase.
Glaciovolcanic emplacement of an intermediate hydroclastic breccia-lobe complex during the penultimate glacial period (190–130 ka), Ruapehu volcano, New Zealand
Authors: Cole R.P. , White J.D.L. , Townsend D.B. , Leonard G.S. , Conway C.E. 
Published: January 2020

Abstract
An intermediate-composition hydroclastic breccia deposit is exposed in the upper reaches of a deep glacial valley at Ruapehu volcano, New Zealand, indicating an ancient accumulation of water existed near the current summit area. Lobate intrusions within the deposit have variably fluidal and brecciated margins, and are inferred to have been intruded while the deposit was wet and unconsolidated. The tectonic setting, elevation of Ruapehu, and glacial evidence suggest that the deposit-forming eruption took place in meltwater produced from an ancient glacier. The breccia-lobe complex is inferred to have been emplaced at &gt; 154 ± 12 ka, during the penultimate glacial period (190–130 ka) when Ruapehu’s glaciers were more extensive than today. This age is based on overlying radiometrically dated lava flows, and by correlation with a well-constrained geochemical stratigraphy for Ruapehu. Field relations indicate that the glacier was at least 150 m thick, and ubiquitous quench textures and jigsaw-fit fracturing suggest that the clastic deposit was formed from non-explosive fragmentation of lava in standing water. Such features are unusual for the high flanks of a volcanic edifice where steep topography typically hinders accumulation of water or thick ice, and hence the formation and retention of hydroclastic material. Although not well-constrained for this time, the vent configuration at Ruapehu is inferred to have contributed to an irregular edifice morphology, allowing thick ice to locally accumulate and meltwater to be trapped.
Emplacement of unusual rhyolitic to basaltic ignimbrites during collapse of a basalt-dominated caldera: The Halarauður eruption, Krafla (Iceland)
Authors: Rooyakkers Shane M. , Stix John , Berlo Kim , Barker Simon J. 
Published: January 2020

AbstractDeposits of the ca. 110 ka Halarauður eruption of Krafla caldera (reconstructed volume = 7 ± 6 km3 dense rock equivalent) include the only spatter-rich ignimbrite known in Iceland, and an exceptionally rare lava-like basaltic ignimbrite. We present a revised stratigraphy and new whole-rock major-element data set for products of this unusual event, one of only three Quaternary ignimbrite eruptions identified in Iceland. Compositions of Halarauður products span a broad range (50.0–74.6 wt% SiO2), reflecting mixing of rhyolite with underplating basalt. Small-volume, valley-ponded, basal pumice- and spatter-bearing lithic breccias and ignimbrite (rhyolite to andesite) reflect rapid column collapse during early opening of ring-fault vents. A transition to voluminous, regionally dispersed spatter agglomerates (dacite to basaltic andesite) marks an abrupt eruptive intensification, as gas-poor magma was squeezed into a developing ring-fault system by the subsiding chamber roof. Spatial heterogeneities in ascent rates and outgassing through this variably dilated fault system caused coeval formation of collapsing plumes and spatter fountains at separate vents. Spatter was entrained into flows from the more explosive vents, which deposited proximal spatter agglomerates and more distal spatter-bearing ignimbrite. Overlying lava-like ignimbrite deposits (basaltic andesite to basalt) reflect a final opening of vents, as mafic magma from deep levels of the chamber was squeezed through a dilated ring-fault system by the subsiding roof block and erupted at uncharacteristically high mass flux. Development of a mature ring-fault conduit system during early tapping of silicic magma appears to be a prerequisite for the emplacement of welded basaltic ignimbrites, and it should be considered as a possible eruption scenario in basalt-dominated systems where silicic magma has been known to also accumulate. Poor preservation of the Halarauður deposits exemplifies the challenges of studying ignimbrite eruptions in frequently glaciated regions like Iceland, where they may be more common than the geological record suggests.
Paleoenvironmental conditions and drainage evolution of the central Anatolian lake system (Turkey) during late Miocene to Pliocene surface uplift
Authors: Meijers Maud J.M. , Brocard Gilles Y. , Whitney Donna L. , Mulch Andreas 
Published: January 2020

Abstract
Continued Africa-Eurasia convergence resulted in post–11 Ma surface uplift of the Central Anatolian Plateau (CAP) and the westward escape of the Anatolian microplate. Contemporaneously, a central Anatolian fluvio-lacustrine system developed that covered extensive parts of the rising CAP. Today, the semi-arid CAP interior—except for the Konya closed catchment—drains toward the Black Sea, the Mediterranean Sea, and the Persian Gulf. Lake connectivity and drainage patterns of the fluvio-lacustrine system in the evolving plateau region are, however, largely unknown.
Here, we present sedimentological and stable isotopic (δ13C and δ18O) data (N = 665) from 13 well-dated lake sections covering the former fluvio-lacustrine depocenters of the southern CAP. Persistently (&gt;1 m.y.) stable paleoenvironmental and hydrological conditions suggest that a low-relief environment characterized the southern CAP during plateau uplift. Throughout the late Miocene, various open and closed lakes of the southern CAP drained into closed, terminal lakes within the plateau interior. Sedimentation east of the Tuz Gölü fault ceased during the early Pliocene (ca. 5.3–3.6 Ma), when the eastern CAP became connected to marine base level as a result of river incision shortly after the switch from regional compression to extension. A final phase of lacustrine carbonate sedimentation characterizes most sampled basins, yet occurred asynchronously over the extent of the CAP. Therefore, the final episode of lacustrine sedimentation is unlikely to have been the result of a climatic event, consistent with the absence of a clear aridification trend in the lacustrine δ18O data. Rather, capping carbonates reflect the interplay of surface uplift and transition from inward- to outward-drained plateau regions and concomitant lake reorganization during the formation of the CAP and its margins.
How can patient-held lists of medication enhance patient safety? A mixed-methods study with a focus on user experience
Authors: Garfield Sara , Furniss Dominic , Husson Fran , Etkind Mike , Williams Marney , Norton John , Ogunleye Della , Jubraj Barry , Lakhdari Hanaa , Franklin Bryony Dean 
Published: January 2020

BackgroundPatients often carry medication lists to mitigate information loss across healthcare settings. We aimed to identify mechanisms by which these lists could be used to support safety, key supporting features, and barriers and facilitators to their use.MethodsWe used a mixed-methods design comprising two focus groups with patients and carers, 16 semistructured interviews with healthcare professionals, 60 semistructured interviews with people carrying medication lists, a quantitative features analysis of tools available for patients to record their medicines and usability testing of four tools. Findings were triangulated using thematic analysis. Distributed cognition for teamwork models were used as sensitising concepts.ResultsWe identified a wide range of mechanisms through which carrying medication lists can improve medication safety. These included improving the accuracy of medicines reconciliation, allowing identification of potential drug interactions, facilitating communication about medicines, acting as an aide-mémoire to patients during appointments, allowing patients to check their medicines for errors and reminding patients to take and reorder their medicines. Different tools for recording medicines met different needs. Of 103 tools examined, none met the core needs of all users. A key barrier to use was lack of awareness by patients and carers that healthcare information systems can be fragmented, a key facilitator was encouragement from healthcare professionals.ConclusionOur findings suggest that patients and healthcare professionals perceive patient-held medication lists to have a wide variety of benefits. Interventions are needed to raise awareness of the potential role of these lists in enhancing patient safety. Such interventions should empower patients and carers to identify a method that suits them best from a range of options and avoid a ‘one size fits all’ approach.
The effects of sintering temperature on superconductivity of MgB2 prepared by hot pressing
Authors: Wang Qi , Li Lei , Zhao Yong , Zhang Hong , Zhang Yong 
Published: January 2020

The [Formula: see text] superconductor bulks were prepared by hot-pressing under the pressure of 55 MPa at different temperatures of 650[Formula: see text]C, 700[Formula: see text]C, 800[Formula: see text]C, 900[Formula: see text]C, 1000[Formula: see text]C, respectively, and the hot-pressing effects on the superconducting properties of [Formula: see text] bulks were investigated. The density of bulk samples increased with the rise of sintering temperature and the density reached to the maximum value when the sintering temperature rose to 1000[Formula: see text]C. For the sample sintered at 1000[Formula: see text]C, the critical transition temperature ([Formula: see text] reached the highest value of 38.8 K despite the high content of [Formula: see text] (30.62 wt.%). However, the critical current density ([Formula: see text] did not increase with the increase in the density and [Formula: see text]. The sample sintered at 700[Formula: see text]C maintained the high superconducting volume and had a small grain size, thus providing the best magnetic flux pinning force and [Formula: see text]. An effective hot-pressing process to improve [Formula: see text] might be the way to prepare by further increasing the density of sintering samples at 700[Formula: see text]C.
Population spatial frequency tuning in human early visual cortex
Authors: Aghajari Sara , Vinke Louis N. , Ling Sam 
Published: January 2020

Neurons within early visual cortex are selective for basic image statistics, including spatial frequency. However, these neurons are thought to act as band-pass filters, with the window of spatial frequency sensitivity varying across the visual field and across visual areas. Although a handful of previous functional (f)MRI studies have examined human spatial frequency sensitivity using conventional designs and analysis methods, these measurements are time consuming and fail to capture the precision of spatial frequency tuning (bandwidth). In this study, we introduce a model-driven approach to fMRI analyses that allows for fast and efficient estimation of population spatial frequency tuning (pSFT) for individual voxels. Blood oxygen level-dependent (BOLD) responses within early visual cortex were acquired while subjects viewed a series of full-field stimuli that swept through a large range of spatial frequency content. Each stimulus was generated by band-pass filtering white noise with a central frequency that changed periodically between a minimum of 0.5 cycles/degree (cpd) and a maximum of 12 cpd. To estimate the underlying frequency tuning of each voxel, we assumed a log-Gaussian pSFT and optimized the parameters of this function by comparing our model output against the measured BOLD time series. Consistent with previous studies, our results show that an increase in eccentricity within each visual area is accompanied by a drop in the peak spatial frequency of the pSFT. Moreover, we found that pSFT bandwidth depends on eccentricity and is correlated with the pSFT peak; populations with lower peaks possess broader bandwidths in logarithmic scale, whereas in linear scale this relationship is reversed. NEW & NOTEWORTHY Spatial frequency selectivity is a hallmark property of early visuocortical neurons, and mapping these sensitivities gives us crucial insight into the hierarchical organization of information within visual areas. Due to technical obstacles, we lack a comprehensive picture of the properties of this sensitivity in humans. Here, we introduce a new method, coined population spatial frequency tuning mapping, which circumvents the limitations of the conventional neuroimaging methods, yielding a fuller visuocortical map of spatial frequency sensitivity.
Ampakine pretreatment enables a single brief hypoxic episode to evoke phrenic motor facilitation
Authors: Wollman L. B. , Streeter K. A. , Fuller D. D. 
Published: January 2020

Phrenic long-term facilitation (LTF) is a sustained increase in phrenic motor output occurring after exposure to multiple (but not single) hypoxic episodes. Ampakines are a class of drugs that enhance AMPA receptor function. Ampakines can enhance expression of neuroplasticity, and the phrenic motor system is fundamentally dependent on excitatory glutamatergic currents. Accordingly, we tested the hypothesis that combining ampakine pretreatment with a single brief hypoxic exposure would result in phrenic motor facilitation lasting well beyond the period of hypoxia. Phrenic nerve output was recorded in urethane-anesthetized, ventilated, and vagotomized adult Sprague-Dawley rats. Ampakine CX717 (15 mg/kg iv; n = 8) produced a small increase in phrenic inspiratory burst amplitude and frequency, but values quickly returned to predrug baseline. When CX717 was followed 2 min later by a 5-min exposure to hypoxia ( n = 8; [Formula: see text] ~45 mmHg), a persistent increase in phrenic inspiratory burst amplitude (i.e., phrenic motor facilitation) was observed up to 60 min posthypoxia (103 ± 53% increase from baseline). In contrast, when hypoxia was preceded by vehicle injection (10% 2-hydroxypropyl-β-cyclodextrin; n = 8), inspiratory phrenic bursting was similar to baseline values at 60 min. Additional experiments with another ampakine (CX1739, 15 mg/kg) produced comparable results. We conclude that pairing low-dose ampakine treatment with a single brief hypoxic exposure can evoke sustained phrenic motor facilitation. This targeted approach for enhancing respiratory neuroplasticity may have value in the context of hypoxia-based neurorehabilitation strategies. NEW & NOTEWORTHY A single brief episode of hypoxia (e.g., 3–5 min) does not evoke long-lasting increases in respiratory motor output after the hypoxia is concluded. Ampakines are a class of drugs that enhance AMPA receptor function. We show that pairing low-dose ampakine treatment with a single brief hypoxic exposure can evoke sustained phrenic motor facilitation after the acute hypoxic episode.
Inclusion of Endogenous Plasma Dehydroepiandrosterone Sulfate and Mammographic Density in Risk Prediction Models for Breast Cancer
Authors: Gabrielson Marike , Ubhayasekera Kumari A. , Acharya Santosh R. , Franko Mikael Andersson , Eriksson Mikael , Bergquist Jonas , Czene Kamila , Hall Per 
Published: January 2020

Abstract

Background:
Endogenous hormones and mammographic density are risk factors for breast cancer. Joint analyses of the two may improve the ability to identify high-risk women.

Methods:
This study within the KARMA cohort included prediagnostic measures of plasma hormone levels of dehydroepiandrosterone (DHEA), its sulfate (DHEAS), and mammographic density in 629 cases and 1,223 controls, not using menopausal hormones. We evaluated the area under the receiver-operating curve (AUC) for risk of breast cancer by adding DHEA, DHEAS, and mammographic density to the Gail or Tyrer–Cuzick 5-year risk scores or the CAD2Y 2-year risk score.

Results:
DHEAS and percentage density were independently and positively associated with breast cancer risk (P = 0.007 and P &lt; 0.001, respectively) for postmenopausal, but not premenopausal, women. No significant association was seen for DHEA. In postmenopausal women, those in the highest tertiles of both DHEAS and density were at greatest risk of breast cancer (OR, 3.5; 95% confidence interval, 1.9–6.3) compared with the lowest tertiles. Adding DHEAS significantly improved the AUC for the Gail (+2.1 units, P = 0.008) and Tyrer–Cuzick (+1.3 units, P = 0.007) risk models. Adding DHEAS to the Gail and Tyrer–Cuzick models already including mammographic density further increased the AUC by 1.2 units (P = 0.006) and 0.4 units (P = 0.007), respectively, compared with only including density.

Conclusions:
DHEAS and mammographic density are independent risk factors for breast cancer and improve risk discrimination for postmenopausal breast cancer.

Impact:
Combining DHEAS and mammographic density could help identify women at high risk who may benefit from individualized breast cancer screening and/or preventive measures among postmenopausal women.
Composição do leite humano: o alimento ideal
Authors: Calil Valdenise Martins Laurindo Tuma , Falcão Mário Cícero 
Published: January 2020

Todas as mães devem ser encorajadas a oferecer seu próprio leite para seus filhos. Apesar do advento das fórmulas infantis, nenhuma dessas se equipara ao leite humano. O leite humano possui inúmeras vantagens: aspectos higiênicos, imunológicos, psico-sociais e cognitivo, bem como aquelas relativas à prevenção de doenças futuras; devem ser consideradas ainda as vantagens econômicas provenientes do menor custo e do efeito anticoncepcional, bem como os benefícios do aleitamento sobre o organismo materno. O leite humano possui uma composição nutricional balanceada em termos de proteínas, carboidratos e gorduras, promovendo crescimento e desenvolvimento adequados. Por isto, aalimentação de recém-nascidos e lactentes com o leite de suas próprias mães é recomendado durante dois primeiros anos de vida.
Avaliação perioperatória da viabilidade intestinal
Authors: Esteves Fernando Pinho , Caravatto Pedro Paulo De Paris , Yamakami Lucas Yugo Shiguehara , Araújo Sérgio Eduardo Alonso , Genzini Tércio , Perosa Marcelo 
Published: January 2020

A determinação da viabilidade de segmentos intestinais e do grau de isquemia a partir de critérios clínicos pode ser de extrema dificuldade para o cirurgião. Faz-se necessário lançar mão de métodos auxiliares para se atestar o grau de comprometimento da alça intestinal, muitas vezes inaparenteà avaliação clínica. O presente trabalho apresenta uma revisão de literatura dos principais métodos existentes para se fazer essa avaliação, descrevendo a técnica e equipamentos necessários para cada um, bem como os resultados da aplicação dos mesmos. Os principais métodos auxiliares encontrados na literatura se dividem em experimentais: eletromiografia, laser Doppler sem contato e Imagem térmica; e clínicos: avaliação exclusiva por critérios clínicos, Doppler ultrassom, laser Doppler, injeção intravascular de corantes, oximetria superficial, oximetria de pulso, termometria, pHmetria, tonometria e fotopletismografia infravermelha. São também reinterados os resultados da indicação e realização das relaparotomias no manejo de pacientes com insuficiência vascular mesentérica. Após a revisão de literatura, pudemos concluir que o Doppler ultrassom e a injeção intravenosa de fluoresceína representam os métodos auxiliares para a avaliação perioperatória da viabilidade intestinal mais utilizados devidoprincipalmente ao seu baixo custo e relativa facilidade de uso. Optamos por destacar o papel da laparoscopia pós-operatória no segmento de pacientes submetidos ao tratamento cirúrgico de insuficiência vascular mesentérica, em especial naqueles em que a avaliação da viabilidade intestinal foi duvidosa.
Tendências temporais da morbidade e da mortalidade por doenças respiratórias na cidade de São Paulo
Authors: Toyoshima Marcos Tadashi Kakitani , Ito Gláucia Munemasa , Gouveia Nelson 
Published: January 2020

Doenças respiratórias são importante causa de morbi-mortalidade em todas as faixas etárias, com considerável impacto econômico e social. Diversos autores vêm apontando um aumento nas hospitalizações e mortes por algumas causas respiratórias, porém em nosso meio, poucos estudosanalisaram estas tendências recentemente. No presente trabalho, dados de hospitalizações para o período de 1995 a 2000 e de mortalidade para 1991-2000 foram analisados através de tabelas e gráficos descritivos, testes de correlação e de tendência linear. Observou-se que houve decréscimo na taxa de internações por doenças respiratórias entre 1995-1997 e tendência de aumento de 1997-2000 em todas as idades. Tendência crescente foi também observada na mortalidade por doenças respiratórias entre 1991-2000. Padrões específicos para diferentes grupos de doenças respiratórias, diferentes faixas etárias e sexos foramobservados. Concluímos que no período estudado, houve participação importante na morbi-mortalidade respiratória de doenças agudas, como as pneumonias, mas com tendência a diminuir a sua participação, ao contrário de doenças crônicas como a DPOC. Estes resultados indicam uma mudança no perfil destas doenças, o que traz conseqüências imediatas para a formulação de políticas de saúde.