bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigation on combination of vapor cooled shield (VCS) and multilayer insulation (MLI) for cryogenic application
Authors: Jiang W. B , Yang Z. H. , Zuo Z. Q. , Sun P. J. , Li P. , Huang Y. H.
Published: June 2020

The long-term storage of cryogenic propellants on orbit under thermal and pressure control is a promising enabling technology for future space exploration. The combination of vapor cooled shield (VCS) and multilayer insulation (MLI) is considered as an effective passive thermal control method for such missions. To experimentally investigate the thermal insulation performance of VCS and MLI combination (MLI/VCS), a cryogen boil-off calorimeter system has been designed and fabricated. It is capable of measuring the heat flux through the VCS and MLI combination, as well as the temperature profiles both on the VCS and inside the MLI. The insulation effectiveness of MLI/VCS is evaluated with liquid nitrogen as the simulated cryogen in the warm-boundary temperature range from 200 K to 350 K. For the warm boundary temperature of 350K case, the insulation performance comparison between MLI/VCS and MLI only is conducted. In addition, the heat transfer behaviour within the insulation combination is discussed in detail.
Experimental measurements on MLI performance from 20-60 K to 4.2 K
Authors: Venturi V. , Koettig T. , Chorowski M. , Polinski J. , Parma V.
Published: June 2020

Future accelerators like the Future Circular Collider (FCC) under study at CERN, will be considerably larger than the Large Hadron Collider (LHC) presently in operation, with consequent increasing demands for cryogenically efficient cryostat solutions. MLI insulating systems remain the technology of choice for large accelerators due to the compromise they offer between thermal performance and cost-effectiveness. Thermal design solutions for cryostats can employ different combinations of thermal shields operating at intermediate temperatures, with optimally chosen MLI solutions. Data in literature is scarce for MLI performance at 4.2 K when operating with a thermal shield at a temperature between 60 K and 20 K. Therefore, a dedicated test program for the qualification of MLI samples is underway at CERN, exploring different MLI configurations, shielding radiative heat from 20-60 K to 4.2 K and with residual gas pressures between 1×10−6 and 1×10−4 mbar. This paper presents results from the test campaign.
Experimental study of carbon dioxide desublimation and sublimation process on low temperature surface
Authors: Wang Y N , Pfotenhauer J M , Qiu L M , Zhi X Q , Jiang X B
Published: June 2020

Cryogenic carbon dioxide capture by the desublimation method has the advantage of being contamination free and energy efficient under high concentration. Due to the difficulty of collecting solid CO2 after desublimation, this method has not been applied. In this paper, a visual experimental setup for carbon dioxide desublimation and sublimation on a low temperature surface is introduced in detail. The core part of the experimental set-up is a visual tube-in-tube counterflow heat exchanger consisting of a Pyrex glass tube with a larger diameter and a stainless-steel tube with a smaller diameter. The crystal growth and dissipation occur on the precooled outer surface of the inner tube, which is recorded by a camera. When carbon dioxide desublimates under different working conditions, such as temperature and supersaturation, the growth shape and growth rate of the solid are different. The thermal properties of the solid such as porosity, thermal conductivity and density are also different, leading to variations in the sublimation process and speed. Three distinct sublimation processes are discussed in this paper to provide guidance on the actual carbon capture process.
Compression and thermal conductivity tests of Cryogel® Z for use in the ultra-transparent cryostats of FCC detector solenoids
Authors: Ilardi V , Busch L N , Dudarev A , Koettig T , de Sousa P Borges , Liberadzka J , Silva H , Kate H H J ten
Published: June 2020

The Future Circular Collider (FCC) study includes the design of the detector magnets for the FCC-ee+ (electron-positron) collider, requiring a 2 T solenoid for particle spectrometry, and for the FCC-hh (proton-proton) collider, with a 4 T detector solenoid. For both solenoids and their cryostats, CERN is developing an innovative and challenging design in which the solenoids are positioned inside the calorimeters, directly surrounding the inner tracker. For this purpose, the cryostats must be optimized to have maximum radiation transparency. They are structured as a sandwich of thinnest possible metallic shells for achieving vacuum tightness, supported by layers of low density and highly radiation transparent insulation material, still providing sufficient mechanical resistance and low thermal conductivity. In this respect, thermal and mechanical analysis of innovative insulation materials are currently being carried out. The first material of interest, Cryogel® Z, is shaped as a flexible composite blanket, which combines silica aerogel with reinforcing fibers and a density of 160 kg/m3. It allows a 4 m bore, 6 m long FCC-ee+ detector solenoid cryostat with a total thickness of 250 mm. CERN has investigated the compression of Cryogel® Z under 1 bar equivalent mechanical load and its thermal conductivity between 10 K and room temperature, as well as the critical phenomena of thermal shrinkage and outgassing. We present the test results, as a first overview on the material.
Trial Manufacturing of Jelly-Rolled Nb/Al Monofilamentary Wire with Very Small Diameter below 50 microns
Authors: Kikuchi Akihiro , Iijima Yasuo , Ichinose Ataru , Kawano Masatoshi , Yamamoto Masaru , Kimura Motoyoshi , Nagamatsu Jun , Otsubo Masato , Hirata Kazuto , Nimori Shigeki , Tsuchiya Kiyosumi
Published: June 2020

Jelly-rolled Nb/Al composite monofilamentary wires having an outer diameter of 50 microns and more than 100 meters in length were successfully fabricated. Moreover, some of these thin wires were additional drawn to 30 microns in outer diameter in this study. We recognized again that jelly-rolled Nb/Al composite monofilamentary wires have excellent cold workability and drawability. The transmission electron microscopic observation revealed that the niobium and aluminum laminations retained a nano-scaled fiber composite structure in the longitudinal direction like the microarchitecture of Japanese bamboo, even in the very thin wire with an outer diameter of 30 μm. The thickness of the aluminum sheet is approximately 70 nm, which is almost comparable to the value calculated from the reduction ratio. The critical temperature of 16.2 K (on set) and 15.7 K (off set) were obtained after the diffusion reaction at 850°C for 10 h. The transport critical currents in liquid helium (4.2 K) under external magnetic fields of 1 T and 8 T are 7.2 A and 0.7 A, corresponding to non-Cu critical current densities of 15,000 and 1,500 A/mm2, respectively. These values are greater than those of industrial Nb-Ti and MgB2 commercial multifilamentary wires.
Liquid Nitrogen Cooled Superconducting Power Cable with No Solid Insulation
Authors: Al-Taie A , Telikapalli S , Cheetham P , Kim C H , Pamidi S V
Published: June 2020

In an attempt to eliminate solid insulation challenges in cryogenic superconducting power cables, a new design concept for liquid cryogen cooled superconducting power cable was investigated. The design is based on superconducting gas insulated line (S-GIL). The design used liquid cryogen as the sole insulation medium. The suitability of the design for medium voltage power cables is discussed and the benefits of eliminating a solid insulation were identified. Experiments on 1-m long model cables with insulator tubes as spacers showed that the design is suitable for cables at 50 kV or higher. The actual limits could not be identified because of the experimental limitations originated from limited standoff distances in the measurement setup used. On a fundamental level, the investigations presented in the study showed a direct correlation between the intrinsic dielectric strength of the cryogen used and the maximum tolerated voltage for a given diameter of the cable system. The results show the promise for liquid nitrogen (LN2) and liquid hydrogen (LH2) cooled cables for various medium voltage applications, including electric aviation and electric ships.
Learning styles for algebra concepts: The case of engineering students at the Universidad de Santander (Valledupar, Colombia)
Authors: Vidal-Tovar C R , Valle-Fuentes H , Rios-Dominguez I C , Castro-Alfaro A F
Published: June 2020

The objective of this research was to evaluate the learning styles for algebra concepts of the students of the industrial engineering program of the University of Santander, Valledupar, Cesar, Colombia. A descriptive study was developed, consisting of 40 algebra students and 6 mathematics teachers, the questionnaire is self-administered elaborated with a dichotomous scale for the student and for interpretation of the means, a scale was designed based on a scale between zero and five that reveals the score obtained in said test, the styles studied were active, reflective, theoretical and pragmatic. Concluding that the predominant style is the pragmatic and theoretical, which allowed to select and apply strategies aimed at generating interactivity between students and teachers around the knowledge of algebra.
Potential Energy savings in compressed air systems in industrialized cities. A case study in Barranquilla and Cartagena
Authors: Herrera Hernan Hernandez , Silva-Ortega Jorge Iván , Leonel Martínez Diaz Vicente , Pons Aliana Gomez , Sanchez Zaid García
Published: June 2020

The increase of energy consumption, global warming, resource depletion and the rise of policies focused on climate change and greenhouse gas emissions reductions, have promoted to countries and industries the implementation of strategies focused on increase energy efficiency and reduce GHG emissions. Compressed Air Systems (CASs) are one of the most widespread systems used in industry. In countries such as China, USA, Australia, France and Italy, CASs accounts around 10% of the overall electricity costs. In Colombia the energy used in the industrial sector, rise the 33 % of the total energy consumption, equal to 481.429 TJ/year; the electricity consumption is a 13 % of this value, equivalent to 13,3 TWh/year. This paper determine the potentials energy saving of CASs for two industrial cities of the Colombian Caribbean Coast region, showing that there is a high energy saving potential, around 50 GWh/year and a reduction of CO2 emissions of 10,702 tons of CO2/year, which can be taken in consideration by the government and organizations to develop projects focused on reduce energy consumption and mitigate CO2 emissions.
Thermal comfort evaluation in an educational building with air conditioning located in the warm tropical climate of Colombia
Authors: Balbis-Morejon M , Noya-Sambrano A
Published: June 2020

The objective of this work is to evaluate the perception of thermal comfort that students have in building 10 of the Universidad de la Costa located in the city of Barranquilla. For the investigation the methods for the thermal comfort evaluation are analyzed, selecting the Steady-State methodology of Fanger according to the ASHRAE 55 Standard. With the application of the surveys, the thermal sensation that the students had in the building was evaluated, which was preferably fresh and thermal acceptability where 87% responded satisfactorily to indoor climate conditions in classrooms. It was also obtained that the perception of inner thermal comfort is between 21.1 ° C and 23 ° C of temperature. With the results obtained, recommendations are issued to ensure that students feel thermal comfort and the proper regulation of air conditioning systems.
Thermal energy capture by pyroelectric effect
Authors: Cárdenas F , Rodríguez J
Published: June 2020

Taking advantage of the physical nature of the pyroelectric materials, in this investigation a characteristic of these materials known as the pyroelectric effect was studied and corroborated, which allows this type of materials are sensitive to infrared electromagnetic radiation, and whose response can be seen in the form of electric potential difference. In this way, in this document the theoretical basis of operation of this effect is presented, and in turn, the results of experiments carried out in laboratories of the University of Santo Tomás Bogotá D.C. The experiments were performed using the “PIR325” sensor, which is composed of two thin films of pyroelectric material. In the first instance, the response of the sensor to thermal electromagnetic radiation produced by the human body is obtained, in the second instance, the same experiment is repeated, However, on this occasion, a Fresnel lens is used to ensure the highest infrared electromagnetic energy collection. Finally, the capture of the signals obtained in each experiment is performed and the results are contrasted, where the theoretical basis of the pyroelectric effect is demonstrated, and in turn, the importance of using a Fresnel lens in applications to carry out this type of sensors.
Technological surveillance as element for the positioning of public universities
Authors: Moya F O , Villero S L , Perez F P
Published: June 2020

This research work is primarily aimed at Technological Surveillance as an Element for the Positioning of Public Universities. This research is characterized by being descriptive, non-experimental design of transectional-descriptive type. The population was made up of the National Open and Distance University and the University of La Guajira, the units of informants made up of the managers responsible for the technologies in the mentioned universities. For the data collection, a simple questionnaire composed of 57 items and constituted by the response alternatives was always, almost always, sometimes, never and almost never. In turn, for the validation of the data collection instrument, it was necessary to submit it to 5 an expert and to apply a reliability test through the Alpha Cronbach statistics formula, giving a result of 0.83 for the Technological Surveillance variable. An analysis of the results obtained in the research was carried out, the presence in public universities is reiterated, however, there is evidence of weakness in the activities for the positioning of the Technology Watch.
Student perception of the use of ICT on learning Morphophysiology
Authors: Quintana A
Published: June 2020

The possibility of working in Morphology using the Technologies of Information and Communication promoting an interactive process focused on the student, who does not leave dependence, sometimes excessive, of the teachers to achieve the objectives. The general objective was to determine the importance of the use of ICT in Morphophysiology learning. A cross-sectional descriptive study with a quantitative approach was carried out. The results of the application of a questionnaire that collected the information in several dimensions. A number of 90 people were surveyed, which accounts for 32% of the population of morphology and physiology basic science students of the Nursing, Surgical Instrumentation and Prehospital Care programs of the Rafael Núñez University Corporation of Cartagena, in the period between February and June 2018. The results show that the use of ICT to support Morphophysiology learning is very well received by students and favors the learning in health sciences. ICT are tools that validate and support the observation and experimentation in the laboratory simulation.
Building a prototype for functional analysis of the energy potential of the water flow in pipe ½ “using microturbines applied to Unidades Tecnológicas de Santander
Authors: Ascanio-Villabona J G , Sandoval-Rodriguez C L , Rincón-Quintero A D , Tarazona-Romero B E , Paez-Castro R E
Published: June 2020

The project aims to build a working prototype for analysis of potential energy of water flow in pipe ½ “by using micro tangential turbines with a loss running low, constituting a small-scale model for the study power generation thereof, setting parameters related to a hydraulic distribution system operation residential drinking water. Taking advantage of the electric power, a microturbine is obtained by decanting flow through it. The research methodology is descriptive quantitative approach, to develop the project initially performed a literature review, followed by identification of the electrical variables and characteristics of the prototype to generate a simulation of a real hydraulic circuit, it followed this comes the recognition and selection of the elements for retrofitting. Thus, as looking through prototype and analysis of the energy potential, generating an academic, social and environmental impact on the institution; since being pioneers in this type of project it is expected to generate the conceptual foundations in the community, enabling understanding of the use of this resource and future implementation. social and environmental in the institution; since being pioneers in this type of project it is expected to generate the conceptual foundations in the community, enabling understanding of the use of this resource and future implementation. social and environmental in the institution; since being pioneers in this type of project it is expected to generate the conceptual foundations in the community, enabling understanding of the use of this resource and future implementation.
Structural analysis of a food truck subjected to impact loads
Authors: Argüello Édison , Donoso Caterine , Arteaga Oscar , Chiluisa Kléber , Hernán Morales V , Aguirre Ronny P , Perez Kevin , Morales Klever D
Published: June 2020

The article focuses on the evaluation of impact loads to the structural design of a conventional food truck through static lateral collision tests with dynamic and static study based on several requirements and regulations of the international standard (ECER95) where force determine of impact generated laterally in a totally inelastic. The physical variables that interact in this phenomenon with the variation of mass, velocity and determine their real impact are analyzed with mathematical equations. The validation of the combined loads was developed by CAE software applying the LRFD method complying with Regulation No. 95 of the Economic Commission for Europe (UNECE) of the United Nations with a collision between the stationary conventional food truck and a vehicle, which impacts it at 50 km / h where the deformations under United Nations Regulations No. 95 and No. 66 are determined, guaranteeing the occupants survival.
Comparison of 3D printed trabecular structure with porous plasma spray: A method based on mapping the local modulus of elasticity
Authors: Cvrček Ladislav , Denk František , Čejka Zdeněk
Published: June 2020

The surface of orthopaedic bone implants is in most cases formed by porous plasma spray. The introduction of 3D printing into the production of implants has made it possible to replace plasma spray with a trabecular bone-like structure that can be fabricated by 3D printing. The principle is to create a suitable surface porosity for anchoring the implant in the bone and adapting the modulus of elasticity to the bone properties. The elastic behaviour of both the structures can be compared by means of a compression test, but it is not possible to compare the modulus of elasticity at the local sites. The aim of the work was to verify the possibility to use the nanoindentation method for the local testing of the modulus of elasticity. The selected method made it possible to map the so-called reduced modulus of elasticity at the precisely defined places. Specifically, the 3D printed trabecular structure of Ti6Al4V ELI was compared with titanium plasma spraying. The printed structure with a bulk porosity of 77% showed the local modulus of elasticity in the range of 57–97 GPa depending on the test site. In contrast, for the plasma spray with a volume porosity of 28%, the modulus of elasticity was around the average value of 54 GPa. At the same time, the microstructure and chemical composition were analysed at the critical points of the structure crossover or the transition from the bulk material to the trabecular structure. No change in the microstructure or chemical composition was observed. Both structures bring the modulus of elasticity closer to the bone modulus of elasticity, but 3D printing offers more possibilities to modify the elastic behaviour and the shape and pore size as well.
Effect of Sn content on the mechanical properties and corrosion behavior of Mg-3Al-xSn alloys
Authors: Yu Zhaochen , Huang Qianfei , Zhang Wentao , Luo Chao , Guan Hongyu , Chen Yang , Song Honggun , Hu Zhi , Luc Chassagne
Published: June 2020

The effect of Sn content on the mechanical properties and corrosion behavior of Mg-3Al-xSn alloys was investigated by SEM-EDXS, XRD, electrochemical measurements, and scanning Kelvin probe force microscopy (SKPFM). The results showed that when the Sn content was 1.4 wt%, Sn dissolved in the α-Mg matrix and then precipitated as an intermetallic compound (Mg2Sn). The combined results of mass loss, hydrogen evolution, and electrochemical measurements indicated that Mg-3Al-1Sn had a low corrosion rate. The SKPFM results showed that the Volta potential of Mg2Sn particles, Al-Mn, and β-Mg17Al12 phases were 100, 80, and 50 mV higher than the matrix, respectively. Therefore, the Mg2Sn phase that formed in Mg-3Al-xSn served as a local cathode due to its high potential, which accelerated microgalvanic corrosion along with the secondary local cathode (Al-Mn). The Sn solution strengthening and secondary phase strengthening (fine Mg2Sn particles) improved the mechanical properties of the Mg-3Al-xSn alloys.
The Archaeology of Qhapaq Ñan (Inca Royal Road)
Authors: Perales Manuel
Published: June 2020

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Anthropology. Please check back later for the full article.

Throughout history, trails, paths, and roads have been fundamental components for the development of human societies, particularly in the case of those that achieved complex forms of organization. In this sense, many ancient states implemented road systems that facilitated the flow of people and goods throughout their domains, at the same time that they strengthened control over conquered populations and sustained the structure of the government apparatus. In the case of Tawantinsuyu, the powerful state built by the Incas, rulers ordered the construction of a vast and sophisticated network of roads that extended from southern Colombia to the central region of Chile and the Argentinian northwest, running through territories currently belonging to Ecuador, Peru, and Bolivia. Although the entire network is known today as Qhapaq Ñan, this term originally referred only to the major axis of the system, represented by the great royal road that connected Cusco, the Inca capital, with Quito and the northern border of the empire.

Due to the advanced technology used in their design and construction, Inca roads garnered the admiration of the earliest Europeans in the Andes, who praised the level of organization and administration of communications handled by the state, as well as the integral infrastructure of the whole road system. Features of the system that were especially praised by the Spanish were bridges, storehouses, and facilities known as tambos, which were frequently used as inns for travelers during Spanish rule. Later, these references made 19th-century explorers and 20th-century researchers of different nationalities turn their attention to the study of Qhapaq Ñan. Since the 1990s, these studies have shown a marked increase and are being carried out from different disciplinary fields, theoretical perspectives, and methodological approaches. After the inclusion of the Qhapaq Ñan in the UNESCO World Heritage List, modern populations from the different localities associated with the Inca roads are increasingly claiming a role in research, conservation, and cultural management projects carried out by governments, institutions, and academics in their respective countries. This has opened an important debate on the processes of cultural heritage declarations, at the same time that it has highlighted the importance of the Qhapaq Ñan as a powerful element of cultural vindication and as a device with great potential for the promotion of Andean integration.
demons in Christian thought
Authors: Wiebe Gregory D.
Published: June 2020

The background of early Christian demonology was in both Hebrew and Greek culture. Jews associated the Greek word daimōn with the false gods of the surrounding nations. This was in many ways an intuitive application of the Greek term. It carried the sense of ambivalent divine or semi-divine power, which significant philosophical traditions understood to mediate between humans and gods. The New Testament carries this theme, though its focus is more on Christ’s exorcisms of demons, and his gift of that power to his disciples, with the early church tying the two together in the theological literature, as well as baptismal exorcisms and renunciations of the devil and idolatry.

Demons were widely thought to have aerial bodies, which allowed them to perform various marvels, like foretelling the future. They were ultimately taken to be fallen angels with Satan as their leader, though this was not a given early in the tradition. While the Christian understanding was that Christ had defeated them on the cross, this was not taken to preclude the ongoing influence of demons in human affairs prior to the final judgement. Indeed, they constituted a significant moral problem for the Christian life, which absolutely opposed them. For Christians, Christ and the demons were the two sides of the fundamental dilemma of every human soul. The problem of demons manifested differently depending on the context, whether in its encounter with false religion, from idolatry to the persecutions the gods inspired; or in the innumerable tempting thoughts encountered in the pursuit of ascetic discipline.
The Opioid Crisis
Authors: Bryan M. Aryana , Hruschak Valerie , Dennis Cory , Rosen Daniel , Cochran Gerald
Published: June 2020

Opioid-related deaths by overdoses quadrupled in the United States from the years 1999 to 2015. This rise in mortality predominately occurred in the wake of historic changes in pain management practices and aggressive marketing of opioid medications such as oxycontin. Prescription opioid misuse and subsequent addiction spilled over to heroin and fentanyl for many. This drug epidemic differed from others in its impact among non-Hispanic whites, leading to drastic changes in how the United States views addiction and chooses to respond. This article offers an overview of opioid use disorder (OUD), its treatment and its relationship with pain. It also discusses special populations affected and provides insight into future directions for research and social work practice surrounding opioid management in the United States. Because of the profession’s emphasis on the person and social environment as well as its focus on vulnerable and oppressed populations, social work plays a critical role in addressing the crisis.
matFR: a MATLAB toolbox for feature ranking
Authors: Zhang Zhicheng , Liang Xiaokun , Qin Wenjian , Yu Shaode , Xie Yaoqin
Published: June 2020

Nowadays, it is feasible to collect massive features for quantitative representation and precision medicine, and thus, automatic ranking to figure out the most informative and discriminative ones becomes increasingly important. To address this issue, 42 feature ranking (FR) methods are integrated to form a MATLAB toolbox (matFR). The methods apply mutual information, statistical analysis, structure clustering and other principles to estimate the relative importance of features in specific measure spaces. Specifically, these methods are summarized, and an example shows how to apply a FR method to sort mammographic breast lesion features. The toolbox is easy to use and flexible to integrate additional methods. Importantly, it provides a tool to compare, investigate and interpret the features selected for various applications.

Availability and implementation

The toolbox is freely available at http://github.com/NicoYuCN/matFR. A tutorial and an example with a dataset are provided.
Fear and Uncertainty: The Surrogacy Triad’s Experience of Social Workers’ Role Ambiguity
Authors: Walker Ruth , van Zyl Liezl
Published: June 2020

In New Zealand, as in the UK, the surrogate is the legal mother of the child until parentage is transferred by the court to the intended parents. Social workers are responsible for assessing the intended parents’ suitability to parent and scrutinising the arrangement. However, courts almost invariably transfer parentage, regardless of their recommendations, with the result that social workers experience a significant amount of role ambiguity. We conducted semi-structured interviews with surrogates and intended parents about their experience of surrogacy in New Zealand, focussing on the changes they would like to see in the regulatory framework, particularly with regards to legal parentage and the involvement of social workers in assessing intending parents’ suitability to parent. Thematic analysis of interview transcripts showed that role ambiguity and role conflict experienced by social workers have their corollary in the experience of intended parents and surrogates, where it manifests as either fear that the adoption could be declined or uncertainty about the purpose of the social worker’s involvement. Although participants recommended that their role be eliminated—along with the adoption process itself—we argue that there is a valuable role for social workers at the beginning of the process.
Tactile direction discrimination in humans after stroke
Authors: Lundblad Linda C , Olausson Håkan , Wasling Pontus , Jood Katarina , Wysocka Anna , Hamilton J Paul , McIntyre Sarah , Backlund Wasling Helena
Published: June 2020

Sensing movements across the skin surface is a complex task for the tactile sensory system, relying on sophisticated cortical processing. Functional MRI has shown that judgements of the direction of tactile stimuli moving across the skin are processed in distributed cortical areas in healthy humans. To further study which brain areas are important for tactile direction discrimination, we performed a lesion study, examining a group of patients with first-time stroke. We measured tactile direction discrimination in 44 patients, bilaterally on the dorsum of the hands and feet, within 2 weeks (acute), and again in 28 patients 3 months after stroke. The 3-month follow-up also included a structural MRI scan for lesion delineation. Fifty-nine healthy participants were examined for normative direction discrimination values. We found abnormal tactile direction discrimination in 29/44 patients in the acute phase, and in 21/28 3 months after stroke. Lesions that included the opercular parietal area 1 of the secondary somatosensory cortex, the dorsolateral prefrontal cortex or the insular cortex were always associated with abnormal tactile direction discrimination, consistent with previous functional MRI results. Abnormal tactile direction discrimination was also present with lesions including white matter and subcortical regions. We have thus delineated cortical, subcortical and white matter areas important for tactile direction discrimination function. The findings also suggest that tactile dysfunction is common following stroke.
Exosomes derived from human amniotic epithelial cells accelerate diabetic wound healing via PI3K-AKT-mTOR-mediated promotion in angiogenesis and fibroblast function
Authors: Wei Pei , Zhong Chenjian , Yang Xiaolan , Shu Futing , Xiao Shichu , Gong Teng , Luo Pengfei , Li Li , Chen Zhaohong , Zheng Yongjun , Xia Zhaofan
Published: June 2020

Background

Diabetic wounds are one of the most common and serious complications of diabetes mellitus, characterized by the dysfunction of wound-healing-related cells in quantity and quality. Our previous studies revealed that human amniotic epithelial cells (hAECs) could promote diabetic wound healing by paracrine action. Interestingly, numerous studies demonstrated that exosomes derived from stem cells are the critical paracrine vehicles for stem cell therapy. However, whether exosomes derived from hAECs (hAECs-Exos) mediate the effects of hAECs on diabetic wound healing remains unclear. This study aimed to investigate the biological effects of hAECs-Exos on diabetic wound healing and preliminarily elucidate the underlying mechanism.

Methods

hAECs-Exos were isolated by ultracentrifugation and identified by transmission electron microscopy, dynamic light scattering and flow cytometry. A series of in vitro functional analyses were performed to assess the regulatory effects of hAECs-Exos on human fibroblasts (HFBs) and human umbilical vein endothelial cells (HUVECs) in a high-glycemic microenvironment. High-throughput sequencing and bioinformatics analyses were conducted to speculate the related mechanisms of actions of hAECs-Exos on HFBs and HUVECs. Subsequently, the role of the candidate signaling pathway of hAECs-Exos in regulating the function of HUVECs and HFBs, as well as in diabetic wound healing, was assessed.

Results

hAECs-Exos presented a cup- or sphere-shaped morphology with a mean diameter of 105.89 ± 10.36 nm, were positive for CD63 and TSG101 and could be internalized by HFBs and HUVECs. After that, hAECs-Exos not only significantly promoted the proliferation and migration of HFBs, but also facilitated the angiogenic activity of HUVECs in vitro. High-throughput sequencing revealed enriched miRNAs of hAECs-Exos involved in wound healing. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses have shown that the target genes of the top 15 miRNAs were highly enriched in the PI3K-AKT pathway. Further functional studies demonstrated that the PI3K-AKT-mTOR pathway was necessary for the induced biological effects of hAECs-Exos on HFBs and HUVECs, as well as on wound healing, in diabetic mice.

Conclusions

Our findings demonstrated that hAECs-Exos represent a promising, novel strategy for diabetic wound healing by promoting angiogenesis and fibroblast function via activation of the PI3K-AKT-mTOR pathway.
Interplay between estrogen and Stat3/NF-κB-driven immunomodulation in lung cancer
Authors: Deng Shanshan , Ramos-Castaneda Marco , Velasco Walter V , Clowers Michael J , Gutierrez Berenice A , Noble Oscar , Dong Yiping , Zarghooni Melody , Alvarado Lucero , Caetano Mauricio S , Yang Shuanying , Ostrin Edwin J , Behrens Carmen , Wistuba Ignacio I , Stabile Laura P , Kadara Humam , Watowich Stephanie S , Moghaddam Seyed Javad
Published: June 2020

K-ras mutant lung adenocarcinoma (LUAD) is the most common type of lung cancer, displays abysmal prognosis and is tightly linked to tumor-promoting inflammation, which is increasingly recognized as a target for therapeutic intervention. We have recently shown a gender-specific role for epithelial Stat3 signaling in the pathogenesis of K-ras mutant LUAD. The absence of epithelial Stat3 in male K-ras mutant mice (LR/Stat3Δ/Δ mice) promoted tumorigenesis and induced a nuclear factor-kappaB (NF-κB)-driven pro-tumor immune response while reducing tumorigenesis and enhancing anti-tumor immunity in female counterparts. In the present study, we manipulated estrogen and NF-κB signaling to study the mechanisms underlying this intriguing gender-disparity. In LR/Stat3Δ/Δ females, estrogen deprivation by bilateral oophorectomy resulted in higher tumor burden, an induction of NF-κB-driven immunosuppressive response, and reduced anti-tumor cytotoxicity, whereas estrogen replacement reversed these changes. On the other hand, exogenous estrogen in males successfully inhibited tumorigenesis, attenuated NF-κB-driven immunosuppression and boosted anti-tumor immunity. Mechanistically, genetic targeting of epithelial NF-κB activity resulted in reduced tumorigenesis and enhanced the anti-tumor immune response in LR/Stat3Δ/Δ males, but not females. Our data suggest that estrogen exerts a context-specific anti-tumor effect through inhibiting NF-κB-driven tumor-promoting inflammation and provide insights into developing novel personalized therapeutic strategies for K-ras mutant LUAD.
What methods are being used to create an evidence base on the use of laboratory tests to monitor long-term conditions in primary care? A scoping review
Authors: Elwenspoek Martha M C , Scott Lauren J , Alsop Katharine , Patel Rita , Watson Jessica C , Mann Ed , Whiting Penny
Published: June 2020

Background

Studies have shown unwarranted variation in test ordering among GP practices and regions, which may lead to patient harm and increased health care costs. There is currently no robust evidence base to inform guidelines on monitoring long-term conditions.

Objectives

To map the extent and nature of research that provides evidence on the use of laboratory tests to monitor long-term conditions in primary care, and to identify gaps in existing research.

Methods

We performed a scoping review—a relatively new approach for mapping research evidence across broad topics—using data abstraction forms and charting data according to a scoping framework. We searched CINAHL, EMBASE and MEDLINE to April 2019. We included studies that aimed to optimize the use of laboratory tests and determine costs, patient harm or variation related to testing in a primary care population with long-term conditions.

Results

Ninety-four studies were included. Forty percent aimed to describe variation in test ordering and 36% to investigate test performance. Renal function tests (35%), HbA1c (23%) and lipids (17%) were the most studied laboratory tests. Most studies applied a cohort design using routinely collected health care data (49%). We found gaps in research on strategies to optimize test use to improve patient outcomes, optimal testing intervals and patient harms caused by over-testing.

Conclusions

Future research needs to address these gaps in evidence. High-level evidence is missing, i.e. randomized controlled trials comparing one monitoring strategy to another or quasi-experimental designs such as interrupted time series analysis if trials are not feasible.
Structure-based identification of small molecules against influenza A virus endonuclease: an in silico and in vitro approach
Authors: K. Sai Disha , Puranik Rashmi , N. Sudheesh , K. Kavitha , Fathima Fajeelath , K. R. Anu , Joseph Alex , J. Anitha , Arunkumar G , Mudgal Piya Paul
Published: June 2020

Influenza viruses are known to cause acute respiratory illness, sometimes leading to high mortality rates. Though there are approved influenza antivirals available, their efficacy has reduced over time, due to the drug resistance crisis. There is a perpetual need for newer and better drugs. Drug screening based on the interaction dynamics with different viral target proteins has been a preferred approach in the antiviral drug discovery process. In this study, the FDA approved drug database was virtually screened with the help of Schrödinger software, to select small molecules exhibiting best interactions with the influenza A virus endonuclease protein. A detailed cytotoxicity profiling was carried out for the two selected compounds, cefepime and dolutegravir, followed by in vitro anti-influenza screening using plaque reduction assay. Cefepime showed no cytotoxicity up to 200 μM, while dolutegravir was non-toxic up to 100 μM in Madin–Darby canine kidney cells. The compounds did not show any reduction in viral plaque numbers indicating no anti-influenza activity. An inefficiency in the translation of the molecular interactions into antiviral activity does not necessarily mean that the molecules were inactive. Nevertheless, testing the molecules for endonuclease inhibition per se can be considered a worthwhile approach.
Research on the synergy incentive evolution among the EPC subjects of energy efficiency retrofitting of existing buildings from the perspective of fairness cognition
Authors: Yang Yanping , Wang Bojun , Liu Xiaodan
Published: June 2020

In the energy performance contracting (EPC) mode, the energy services company (ESCO) involved in energy efficiency retrofitting of existing buildings often faces the parallel construction of multiple tender segments and multi-professional subcontractors. The one-to-many structure for ESCO and subcontractors causes difficulties to the project quality management and directly affects the effect of energy efficiency retrofitting of existing buildings. Therefore, this paper constructs a revenue-sharing incentive model by considering situation where subjects have fairness cognition. Through the social calculation experiment of the model, results show the following: (1) increasing the revenue-sharing coefficient will help to optimize the engineering quality of energy efficiency retrofitting and increase the energy-saving income; (2) in order to get better incentive effect, the engineering quality grade of energy efficiency retrofitting should match with the incentive strength; (3) because of the impact of fairness cognition, the incentive level difference is too large, and the incentive effect will gradually weaken in the subsequent incentive cycle; (4) subcontractor’s effort level changes can prompt ESCO to adjust the corresponding incentive intensity. Finally, some suggestions are put forward to optimize the engineering quality management of energy efficiency retrofitting of existing building, which is of great significance to improve the effect of energy efficiency retrofitting of existing building under EPC mode.
A machine learning–based clinical decision support system to identify prescriptions with a high risk of medication error
Authors: Corny Jennifer , Rajkumar Asok , Martin Olivier , Dode Xavier , Lajonchère Jean-Patrick , Billuart Olivier , Bézie Yvonnick , Buronfosse Anne
Published: June 2020

Objective

To improve patient safety and clinical outcomes by reducing the risk of prescribing errors, we tested the accuracy of a hybrid clinical decision support system in prioritizing prescription checks.

Materials and Methods

Data from electronic health records were collated over a period of 18 months. Inferred scores at a patient level (probability of a patient’s set of active orders to require a pharmacist review) were calculated using a hybrid approach (machine learning and a rule-based expert system). A clinical pharmacist analyzed randomly selected prescription orders over a 2-week period to corroborate our findings. Predicted scores were compared with the pharmacist’s review using the area under the receiving-operating characteristic curve and area under the precision-recall curve. These metrics were compared with existing tools: computerized alerts generated by a clinical decision support (CDS) system and a literature-based multicriteria query prioritization technique. Data from 10 716 individual patients (133 179 prescription orders) were used to train the algorithm on the basis of 25 features in a development dataset.

Results

While the pharmacist analyzed 412 individual patients (3364 prescription orders) in an independent validation dataset, the areas under the receiving-operating characteristic and precision-recall curves of our digital system were 0.81 and 0.75, respectively, thus demonstrating greater accuracy than the CDS system (0.65 and 0.56, respectively) and multicriteria query techniques (0.68 and 0.56, respectively).

Discussion

Our innovative digital tool was notably more accurate than existing techniques (CDS system and multicriteria query) at intercepting potential prescription errors.

Conclusions

By primarily targeting high-risk patients, this novel hybrid decision support system improved the accuracy and reliability of prescription checks in a hospital setting.
Radiographic and clinical characteristics associated with a positive PART (Prone Apprehension Relocation Test): a new provocative exam to elicit hip instability
Authors: Spiker Andrea M , Fabricant Peter D , Wong Alexandra C , Suryavanshi Joash R , Sink Ernest L
Published: June 2020

Hip instability due to mild dysplasia can be a diagnostic challenge. The physical exam is an important adjunct to radiographic evaluation for the clinical diagnosis of hip instability. Herein, we describe a new maneuver to replicate hip instability pain, called the PART (Prone Apprehension Relocation Test). We retrospectively identified patients in our institution’s hip preservation registry who presented for evaluation of hip pain. We divided patients into ‘positive’ or ‘negative’ PART and analyzed associated clinical and radiographic findings. Ninety patients (159 hips) were included, 83 female and 7 male, average age 27.3 ± 9.1 years. Thirty-four hips (21.4%) had a positive PART. There were no significant differences in hip range of motion, lateral center edge angle, or in acetabular depth. There was, however, a significant difference in acetabular version at 3 o’clock between the two test groups (18.5 ± 6.9° in negative, 21.2 ± 4.9° in positive, P = 0.045). There was no association between PART and previously described anterior apprehension testing. Historical methods of diagnosing hip dysplasia may not adequately identify patients with clinical hip instability. We describe a new provocative exam, the PART, which may be helpful in replicating hip instability symptoms in patients with anterior acetabular undercoverage. PART positive patients had significantly more acetabular anteversion at the 3 o’clock position, which is measured on computed tomography and is not visible on standard anteroposterior (AP) pelvis or false profile radiographs. We believe that the PART is a valuable supplement to clinical examination and radiographic measurements to identify patients with symptomatic hip instability.
Racial and Ethnic Disparities Among Participants in US-Based Phase 3 Randomized Cancer Clinical Trials
Authors: Grant Stephen R , Lin Timothy A , Miller Austin B , Mainwaring Walker , Espinoza Andres F , Jethanandani Amit , Walker Gary V , Smith Benjamin D , Ashleigh Guadagnolo B , Jagsi Reshma , David Fuller C , Thomas Charles R , Ludmir Ethan B
Published: June 2020

Although improving representation of racial and ethnic groups in United States clinical trials has been a focus of federal initiatives for nearly 3 decades, the status of racial and ethnic minority enrollment on cancer trials is largely unknown. We used a broad collection of phase 3 cancer trials derived from ClinicalTrials.gov to evaluate racial and ethnic enrollment among US cancer trials. The difference in incidence by race and ethnicity was the median absolute difference between trial and corresponding Surveillance, Epidemiology, and End Results data. All statistical tests were 2-sided. Using a cohort of 168 eligible trials, median difference in incidence by race and ethnicity was +6.8% for Whites (interquartile range [IQR] = +1.8% to +10.1%; P < .001 by Wilcoxon signed-rank test comparing median difference in incidence by race and ethnicity to a value of 0), -2.6% for Blacks (IQR = -5.1% to +1.2%; P = .004), -4.7% for Hispanics (IQR = -7.5% to -0.3%; P < .001), and -4.7% for Asians (IQR = -5.7% to -3.3%; P < .001). These data demonstrate overrepresentation of Whites, with continued underrepresentation of racial and ethnic minority subgroups.