bluuebunny/crossref_metadata_2025_split huggingface dataset:
De Novo Asymmetric Approach to Aspergillide‐C: Synthesis of 4‐epi‐seco‐Aspergillide‐C
Authors: Xing Yalan , O'Doherty George A. 
Published: April 2022

AbstractAn asymmetric approach toward the synthesis of the marine natural product aspergillide‐C has been developed. The convergent asymmetric synthesis uses two asymmetric Noyori transfer hydrogenations to enantioselectively prepare the two key fragments, aC‐1 toC‐7 pyranone fragment and aC‐8 toC‐14β‐keto‐sulfone fragment. The absolute stereochemistry of the pyranone fragment was established by a Noyori reduction ofβ‐furylketoester to form a furyl alcohol. An Achmatowicz rearrangement was used to stereoselectively convert the furyl alcohol in to the key pyranone fragment. The absolute stereochemistry of theβ‐keto‐sulfone fragment was established by a Noyori reduction of an ynone to form a propargyl alcohol. An alkyne zipper isomerization was used to stereospecifically convert the propargyl alcohol in to theβ‐keto‐sulfone fragment. Finally, a Pd‐catalyzedC‐glycosylation was used to diastereoselectively couple the two fragments, which when combined with a reduction and Julia‐Kocienski type elimination formed a protected variant of the 4‐epi‐seco‐acid of aspergillide‐C.
Zooming in or zooming out: Entrants' product portfolios in the nascent drone industry
Authors: Shermon Anavir , Moeen Mahka 
Published: April 2022

AbstractResearch SummaryFaced with demand uncertainty and heterogeneity in a nascent industry, entrants often consider how many customer segments to serve by tailoring the usage breadth of their product portfolios. Portfolio usage breadth is the extent to which products in a portfolio collectively span distinct customer segments. We suggest that when entrants have use experience in contexts that are potential users of the new product, their portfolios exhibit low usage breadth, due to demand‐oriented cognition and knowledge. The relationship is stronger for diversifying entrants relative to startups. The empirical context is the U.S. commercial drone industry, wherein entrants need to adapt their product portfolios for five robust and distinct customer segments of photography, short‐distance inspection, long‐distance surveying, agriculture, and aerial supply chain management.Managerial SummaryNew industries often serve multiple customer segments, each with different preferences. Entrants can either launch products catering to the specific preferences of customers in a small number of segments or launch products targeting numerous segments. Evidence from the U.S commercial drone industry shows that when entrants have experience in one of the customer segments adopting the new industry's product, they tend to introduce products targeting fewer segments. By recognizing the impact of prior experiences on product portfolio development, entrepreneurial leaders gain insights to assess whether their cognitive alignment with a customer segment has restricted their broader exploration of the demand environment, or whether their superior demand knowledge about a customer segment has created a competitive advantage.
High‐Voltage Induced Surface and Intragranular Structural Evolution of Ni‐Rich Layered Cathode
Authors: Liu Hanshuo , Xie Zhong , Qu Wei , Dy Eben , Niketic Svetlana , Brueckner Shawn , Tsay Ken , Fuller Eric , Bock Christina , Zaker Nafiseh , Botton Gianluigi A. 
Published: April 2022

AbstractLayered Ni‐rich lithium transition metal oxides are promising cathode materials for high‐energy‐density lithium‐ion batteries. These cathodes, however, suffer from rapid performance decay under high‐voltage operation. In this work, the electrochemical properties and structural evolution of the LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode upon high‐voltage cycling are investigated. The results show that the NMC811 cathode not only experiences surface evolution with the formation of Li‐deficient rock‐salt layers, but also suffers from drastic intragranular structural changes inside bulk grains after high‐voltage cycling. Direct evidence for the formation of transition‐metal/Li disordering domains with uneven Li content and lattice plane distortion at the internal grains of 4.6 V‐cycled NMC811 are provided with their atomic ordering and spatial distribution clearly resolved. The complex intragranular structural changes impede Li+ diffusion inside bulk material, resulting in kinetic limitation and capacity loss. The results demonstrate that the high‐voltage cycling would induce severe structural degradation at the grain interior of the cathode material beyond surface evolution, which contributes significantly to the rapid performance decay of the NMC811 cathode. The findings provide new insights for developing effective countermeasures to mitigate this degradation pathway.
Atomistic Observation of the Local Phase Transition in MoTe2 for Application in Homojunction Photodetectors
Authors: Wang Yalan , Zhang Miao , Xue Zhongying , Chen Xinqian , Mei Yongfeng , Chu Paul K. , Tian Ziao , Wu Xing , Di Zengfeng 
Published: April 2022

AbstractDirect atomic‐scale observation of the local phase transition in transition metal dichalcogenides (TMDCs) is critically required to carry out in‐depth studies of their atomic structures and electronic features. However, the structural aspects including crystal symmetries tend to be unclear and unintuitive in real‐time monitoring of the phase transition process. Herein, by using in situ transmission electron microscopy, information about the phase transition mechanism of MoTe2 from hexagonal structure (2H phase) to monoclinic structure (1T′ phase) driven by sublimation of Te atoms after a spike annealing is obtained directly. Furthermore, with the control of Te atom sublimation by modulating the hexagonal boron nitride (h‐BN) coverage in the desired area, the lateral 1T′‐enriched MoTe2/2H MoTe2 homojunction can be one‐step constructed via an annealing treatment. Owing to the gradient bandgap provided by 1T′‐enriched MoTe2 and 2H MoTe2, the photodetector composed of the 1T′‐enriched MoTe2/2H MoTe2 homojunction shows fast photoresponse and ten times larger photocurrents than that consisting of a pure 2H MoTe2 channel. The study reveals a route to improve the performance of optoelectronic and electronic devices based on TMDCs with both semiconducting and semimetallic phases.
Mechanical performances of high‐strength concrete‐filled steel tubular medium–long columns with square cross section
Authors: Chen Jun , Liu Zhe , Xiang Ping , Zhang Xuebing , Yang Caiqian , Ding Faxing , Xu Fu , Peng Yue 
Published: April 2022

AbstractIn order to investigate the influence of concrete strength, slenderness ratio, and eccentricity on the ultimate bearing capacity, initial stiffness, and other mechanical properties of square high‐strength steel tubular medium–long column, a total of 11 square column specimens were designed and made. The compression tests were carried out, and the load–longitudinal deformation curve, load–deflection curve, longitudinal strain distribution curve of mid‐span section, and several failure modes of the composite column were obtained. Numerical simulations were conducted, and the results are in good agreement with the experimental results. It is found that the concrete strength has little effect on the initial stiffness of the square high‐strength concrete‐filled steel tubular medium–long column, and the ultimate bearing capacity and initial stiffness decrease with the increase of slenderness ratio and eccentricity, and the eccentricity has a particularly significant influence on the bearing capacity.
Assessment of Mitochondrial Trafficking as a Surrogate for Fast Axonal Transport in Human Induced Pluripotent Stem Cell–Derived Spinal Motor Neurons
Authors: Mehta Arpan R. , Chandran Siddharthan , Selvaraj Bhuvaneish T. 
Published: April 2022

AbstractAxonal transport is essential for the development, function, and survival of the nervous system. In an energy-demanding process, motor proteins act in concert with microtubules to deliver cargoes, such as organelles, from one end of the axon to the other. Perturbations in axonal transport are a prominent phenotype of many neurodegenerative diseases, including amyotrophic lateral sclerosis. Here, we describe a simple method to fluorescently label mitochondrial cargo, a surrogate for fast axonal transport, in human induced pluripotent stem cell–derived motor neurons. This method enables the sparse labeling of axons to track directionality of movement and can be adapted to assess not only the cell autonomous effects of a genetic mutation on axonal transport but also the cell non-autonomous effects, through the use of conditioned medium and/or co-culture systems.
From Bath to Cambridge: The Early Life and Education of Robert Leslie Ellis
Authors: Stray Christopher 
Published: April 2022

AbstractRobert Leslie Ellis was born in Bath on 25 August 1817. His father, Francis Ellis (1772–1842), had held a position in the Admiralty, but resigned when he became the principal heir of his uncle Henry Ellis, formerly Governor of Nova Scotia, who on his death in 1806 left him £10,000 and extensive landholdings in Ireland and elsewhere. Francis and his wife Mary, née Kilbee (1777–1847), had six children, of whom Robert, born in 1817, was the youngest. The family lived in a succession of large houses in Bath, where Francis Ellis, a well-known local figure, was one of the founders of the Bath Literary and Scientific Institution, founded in 1823. The Institution had a well-stocked library which took in both British and continental books and periodicals, and the teenaged Ellis frequented it regularly, reading avidly and conversing with the adult members, who included scholars and scientists of some distinction. His father involved himself in Ellis’s education and was himself a well-educated and inquiring man; his uncle had described him as ‘really a very deserving young man of uncommon abilities and possessed of more scientific and other knowledge than [one] could expect at his years.’ In an account of the Bath literati published in 1854, Francis Ellis was included in a list of ‘men with intelligent and well-informed minds’, and a later supplement stated that ‘Francis Ellis had an enlarged mind, was a good classic, a superior mathematician, and a generally well-informed man’. Ellis’s library contained several hundred books in 1841, when an inventory was taken.
Robert Leslie Ellis as Editor and Contributor to Mathematical Journals
Authors: Crilly Tony 
Published: April 2022

AbstractRobert Leslie Ellis (1817–1859) was a true mathematician. He became a Renaissance man in the style of many Victorians, but the bedrock of his intellectual vitality was mathematics. This, coupled with the breadth of his reading, an extensive general knowledge, and a willingness to examine serious historical and philosophical issues made him an ideal candidate for editorial duties in the 1840s.
Defining Public Health Ethics for Practitioners
Authors: Ortmann Leonard W. 
Published: April 2022

AbstractThis chapter stresses the collective nature of public health, defines public health ethics, and relates the latter to narrative ethics. The chapter offers four ways to define public health ethics; namely, through its problems, practice, procedure, and principles. Every area of Public Health Service poses ethics problems that involves either training issues, compliance with ethical rules and standards, or a utilitarian weighing of courses of action. The practice of public health ethics not only analyzes and addresses emergent ethical problems but also integrates ethics upstream into the design of public health programs. A public health ethics procedure provides a systematic framework for analyzing ethical problems, for designing and evaluating interventions, and for justifying one’s decisions. The chapter explores the core principles found in the American Public Health Association’s 2019 Public Health Code of Ethics. This Code reflects public health’s emphasis on health equity, inclusiveness, and engagement with marginalized communities. Accordingly, the subsequent discussion calls attention to an approach that advocates empathic listening to community members, namely, Human-centered design. The chapter closes by suggesting that narrative ethics can improve the capacity of practitioners to empathically hear the voices and stories of community members and thereby improve public health practice.
Harm Reduction: Tipping the Balance Toward Treatment and Recovery
Authors: Sandul Amy L. , Moore Veda B. 
Published: April 2022

AbstractOpioid use has risen dramatically over the past 40 years. In response, federal programs and policies aimed at decreasing supply of prescription opioids have stabilized excessive prescribing. Unintended consequences of limiting the quantity of prescription opioids in the population has resulted in increased use of illicit drugs and opened a pathway of transition from misuse of pills to injection of heroin and use of potent formulations of cheap, synthetic opioids such as fentanyl. Harm reduction interventions function at the community level to provide health benefits and avoidance of harm to persons engaging in illicit and injection drug use. The Consolidated Appropriations Act of 2016 gives states, local, tribal, and territorial health departments the opportunity to use federal money to support a comprehensive set of harm reduction services. Critics of harm reduction strategies argue that formalizing and legalizing certain activities creates the perception that communities and local authorities are sanctioning or encouraging illicit/illegal drug use. Syringe services programs that provide clean needles and syringes so people who inject drugs are not forced to share or reuse injection equipment, are often at the heart of such controversy. This story addresses tensions that exist in communities grappling with harm reduction approaches to opioid and injection drug use.
A Novel Approach to Public Health Crises Using Narrative Ethics
Authors: Zinner Susan E. 
Published: April 2022

AbstractThis chapter examines several public health issues using the novels The Stand by Stephen King and The Andromeda Strain by Michael Crichton. These two narratives both explore fictional U.S. events, one contained and one out of control, where microorganisms place either a community (The Andromeda Strain) or the entire country (The Stand) at risk. Both novels illustrate the significance of the roles of transparency of public health officials and distribution of accurate information to the public to minimize panic. Similarly, they also address the importance of collaboration of officials at many levels to protect individual, community and national health. When effective, these two efforts establish trust and reduce the spread of epidemics and pandemics worldwide. However, obstacles are many. They include difficult individual personalities which can hamper effective working relationships and the bureaucratic administrative structure of the U.S. public health system.
Empowering Communities That Experience Marginalization Through Narrative
Authors: Lathrop Breanna , Kasambira-Emerson Marcia Mercy R. , Squires Veronica , Santibañez Scott 
Published: April 2022

AbstractResolving to share one’s narrative may empower a person to own and appreciate their personal experiences and encourage fellow marginalized community members to become empowered by owning their own narratives. Respecting people, hearing their stories, and inviting them to share their stories with people with similar lived experiences can become both a reflector of, and contributor to, community empowerment. In this paper, we present a narrative from a woman experiencing major depressive disorder and Type 2 Diabetes. Her personal reflection describes how she came to understand her lived experience and the ways in which social factors impacted her health, and how this understanding contributed to her ongoing healing process. Her work as a Certified Peer Specialist illustrates the ability of her narrative to empower other marginalized community members and inform health interventions. Rather than imposing solutions without community engagement, public health interventions should resonate with the values and voices of community members and stakeholders. When both speaker empowerment and listening are taken into account, public health can avoid harm, maximize positive outcomes, and treat storytellers fairly, as autonomous partners in their own health and the health of their community.
Treatment of Leakage Disease of a Deep Foundation Pit
Authors: Liu Hui , Zhang Xinjie 
Published: April 2022

AbstractDue to the influence of groundwater runoff, the local water stop curtain of a deep foundation pit of a project failed, resulting in leakage of the foundation pit, which seriously threatens the safety of the foundation pit and surrounding buildings. After several rounds of site survey and demonstration, measures were adopted to “treat the leakage utilizing external sealing and internal blocking, a combination of dredging and blocking, and local strengthening”, and an emergency rescue team was established to promptly eliminate potential safety hazards.
Research on Construction Process of Steel Beam Incremental Launching Based on Finite Element Method
Authors: Xiao Yancai , Fu Kun , Li Zhuang , Zeng Zhiping , Bai Jian , Huang Zhibin , Huang Xudong , Yuan Yu 
Published: April 2022

AbstractIn order to ensure the normal operation of the traffic under the bridge, reasonable calculation methods and construction techniques should be adopted for the construction of the newly added railway station. This paper establishes a structural calculation finite element model to calculate and analyze the various construction stages of the steel beam incremental launching construction of the newly-added Gaoping station on the Yichuang-Wanzhou Railway, and systematically study the mechanical properties of the steel beam in the process. The results show that: (1) The deflection of each rod can meet the requirements of the railway bridge steel structure construction specification. However, when the length of the front cantilever of the steel beam reaches 11.4 m, the maximum deflection of the upper and lower chord bars is close to the limit. (2) The load-bearing capacity of each member of the steel beam meets the requirements, which indicates that the structural design of the steel beam and the incremental launching construction plan are reasonable. (3) In view of the complexity and uncertainty of the incremental launching construction process, real-time monitoring of the construction process is required, and the beam should be dropped in time when abnormal conditions occur to ensure the safe operation of the existing line.
Preparation and Impact Resistance of Carbon Fiber Reinforced Metal Laminates Modified by Carbon Nanotubes
Authors: Jia Zehui , Xu Lingwei , Huang Shuangkai , Xu Haoran , Zhang Zhimo , Cui Xu 
Published: April 2022

AbstractFiber reinforced metal laminates (FMLs) are a kind of interlaminar hybrid composites made of metal sheets and fibers alternately stacked and cured at a certain pressure and temperature. In this paper, through the simulation of ABAQUS finite element software and recording the change of projectile velocity, the energy loss of projectile is calculated and the impact resistance is judged. Through the comparison of three groups of simulation experimental results, the energy absorbed by carbon fiber reinforced metal laminate is about 300 times that of aluminum alloy plate, which fully shows that carbon fiber reinforced metal composite has excellent impact resistance compared with aluminum alloy. After adding 1 wt% carbon nanotubes to carbon fiber reinforced metal laminates, the absorbed energy is about 10 times that of the original, which shows that carbon nanotubes improve the ultimate yield stress of resin and materials in epoxy resin and enhance the weakness that the composites are easy to delamination under impact load.
Temperature Distribution and Transmission in Multilayer Porous Asphalt Courses
Authors: Chen Hongqing , Jiang Chunfa , Su Yunfei , Wang Xiaowei 
Published: April 2022

AbstractThe objective of this paper was to investigate the temperature distribution and the law of temperature transmission in multilayer porous asphalt courses. Three types of multilayer porous asphalt courses are designed as the same thickness of actual pavements. In order to achieve this objective, experiments were conducted in an oven with different temperature, and samples were enwrapped with an efficient insulation material except the surface. The final temperature in samples is lower by 5~10 °C than ambient temperature and reduced gradually from top to bottom. The ability of heat transmission is related to the mixture’s air void and ambient temperature. The temperature transmission rate in porous asphalt mixture is lower than traditional dense graded asphalt mixture. At last, temperature transmission formulas of porous asphalt mixture are given.
Research on Support Damage of Highway Bridge Based on Midas
Authors: Fang Miaomiao , Wang Yuqi , Liu Jiaxin , Sun Fan 
Published: April 2022

AbstractDuring the operation of highway bridges, the bearing stiffness will decrease with the service life, and the mechanical properties will also change. In order to study the influence of stiffness damage on bearing. In this paper, a continuous beam bridge is selected for finite element model analysis, and the effects of stiffness damage on bearing force and bearing offset under the conditions of concrete shrinkage and creep and 30 °C temperature difference are comprehensively considered. The results show that the bearing stiffness damage has little influence on the vertical displacement, horizontal displacement and bearing capacity of the bearing, but has a great influence on the vertical compression deformation and durability of the bearing.
Compressive Strength Performance of Additives for Cement-Based Grouting Material with Low Water-Binder Ratio by Response Surface Methodology
Authors: Guo Jiaxu , Hu Shaowei , Zhao Xuan , Tao Xiu , Nie Ying 
Published: April 2022

AbstractIn order to research the influence and the function mechanism of calcium formate and defoaming agent on the compressive strength of cement-based grouting material with low water-binder ratio at different ages, quadratic polynomial regression models were established by RSM, and the mix proportion was optimized. The function mechanism of additives was analysed by macroscopic mechanical properties and microstructure. The results indicated that the response surface method is scientific in optimizing the mix proportion of cement-based grouting material. The optimal mix proportion was obtained as fallow: the calcium formate was 0.64%, the water-binder ratio was 0.21 and the defoaming agent was 0.26%, with taking 1d, 3d, 28d compressive strength as the optimization objective. Calcium formate is highly significant for the early compressive strength of cement-based grouting materials with low water-binder ratio, while the water-binder ratio and defoaming agent are highly significant for that of the middle and late period. Calcium formate promotes the formation of CSH gel and $$\mathrm{Ca}{\left(\mathrm{OH}\right)}_{2}$$

Ca

OH

2

crystallization in the early period, and the defoaming agent can effectively reduce macropores. The results can provide an optimization method for the mix proportion design of cement-based grouting material and a theoretical reference for its mechanical properties.