bluuebunny/crossref_metadata_2025 huggingface dataset:
Epitaxy and characterization of undoped Si/SiGe heterojunctions
Authors: Geng Xin , Zhang Jie-Yin , Lu Wen-Long , Ming Ming , Liu Fang-Ze , Fu Bin-Xiao , Chu Yi-Xin , Yan Mou-Hui , Wang Bao-Chuan , Zhang Xin-Ding , Guo Guo-Ping , Zhang Jian-Jun ,   School of Physics, South China Normal University, Guangzhou 510631, China,   Center for Semiconductor Heterogeneous Materials and Devices, SongShan Lake Materials Laboratory, Dongguan 523830, China,   CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China,   Key Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Sciences, Beijing 100190, China,   College of Sciences, Shanghai University, Shanghai 200444, China
Published: April 2024

Silicon-based semiconductor quantum computing with spin as the encoding unit is compatible with traditional microelectronic processes, easy to expand, and can improve isotope purification and decoherence time, thus attracting much attention. There are fewer reports on the work related to undoped Si/SiGe heterostructures grown by molecular beam epitaxy than those on chemical vapor deposition. An undoped Si/SiGe heterostructure is grown by molecular beam epitaxy (see the attached figure below). The results from scanning transmission electron microscopy and energy-dispersive spectroscopy mapping show an atomic-scale interface with a characteristic length of 0.53 nm. The surface root-mean-square roughness measured by atomic force microscope is 0.44 nm. The X-ray diffraction data show that the Si quantum well is fully strained and the in-plane strain is 1.03%. In addition, the performance of the two-dimensional electron gas is evaluated by low-temperature Hall measurements, which are conducted in the Hall-bar shaped field-effect transistor. The peak mobility is 20.21×104 cm2·V–1·s–1 when the carrier density is about 6.265×1011 cm–2 at 250 mK. The percolation density is 1.465×1011 cm–2. The effective mass of the two-dimensional electron gas is approximately 0.19m0. The power exponential between carrier density and mobility at different gate voltages is 1.026, and the Dingle ratio of the two-dimensional electron gas is in a range of 7–12, indicating that the electrons are scattered by background impurities and semiconductor/oxide interfaces charges. The atomically sharp interface of Si/SiGe heterostructures created by molecular beam epitaxy is beneficial for studying the valley physics properties in silicon. The structural and transport characterizations in this paper lay the foundation for the optimization of Si-based semiconductor quantum dot quantum computing materials.
A three filament mechanistic model of musculotendon force and impedance
Authors: Millard Matthew , Franklin David W. , Herzog Walter
Published: April 2024

The force developed by actively lengthened muscle depends on different structures across different scales of lengthening. For small perturbations, the active response of muscle is well captured by a linear-time-invariant (LTI) system: a stiff spring in parallel with a light damper. The force response of muscle to longer stretches is better represented by a compliant spring that can fix its end when activated. Experimental work has shown that the stiffness and damping (impedance) of muscle in response to small perturbations is of fundamental importance to motor learning and mechanical stability, while the huge forces developed during long active stretches are critical for simulating and predicting injury. Outside of motor learning and injury, muscle is actively lengthened as a part of nearly all terrestrial locomotion. Despite the functional importance of impedance and active lengthening, no single muscle model has all of these mechanical properties. In this work, we present the viscoelastic-crossbridge active-titin (VEXAT) model that can replicate the response of muscle to length changes great and small. To evaluate the VEXAT model, we compare its response to biological muscle by simulating experiments that measure the impedance of muscle, and the forces developed during long active stretches. In addition, we have also compared the responses of the VEXAT model to a popular Hill-type muscle model. The VEXAT model more accurately captures the impedance of biological muscle and its responses to long active stretches than a Hill-type model and can still reproduce the force-velocity and force-length relations of muscle. While the comparison between the VEXAT model and biological muscle is favorable, there are some phenomena that can be improved: the low frequency phase response of the model, and a mechanism to support passive force enhancement.
A retrospective cohort study of Paxlovid efficacy depending on treatment time in hospitalized COVID-19 patients
Authors: Du Zhanwei , Wang Lin , Bai Yuan , Liu Yunhu , Lau Eric HY , Galvani Alison P , Krug Robert M , Cowling Benjamin John , Meyers Lauren A
Published: April 2024

Paxlovid, a SARS-CoV-2 antiviral, not only prevents severe illness but also curtails viral shedding, lowering transmission risks from treated patients. By fitting a mathematical model of within-host Omicron viral dynamics to electronic health records data from 208 hospitalized patients in Hong Kong, we estimate that Paxlovid can inhibit over 90% of viral replication. However, its effectiveness critically depends on the timing of treatment. If treatment is initiated three days after symptoms first appear, we estimate a 17% chance of a post-treatment viral rebound and a 12% (95% CI: 0–16%) reduction in overall infectiousness for non-rebound cases. Earlier treatment significantly elevates the risk of rebound without further reducing infectiousness, whereas starting beyond five days reduces its efficacy in curbing peak viral shedding. Among the 104 patients who received Paxlovid, 62% began treatment within an optimal three-to-five-day day window after symptoms appeared. Our findings indicate that broader global access to Paxlovid, coupled with appropriately timed treatment, can mitigate the severity and transmission of SARS-Cov-2.
Germline cis variant determines epigenetic regulation of the anti-cancer drug metabolism gene dihydropyrimidine dehydrogenase (DPYD)
Authors: Zhang Ting , Ambrodji Alisa , Huang Huixing , Bouchonville Kelly J. , Etheridge Amy S. , Schmidt Remington E. , Bembenek Brianna M. , Temesgen Zoey B. , Wang Zhiquan , Innocenti Federico , Stroka Deborah , Diasio Robert B. , Largiadèr Carlo R. , Offer Steven M.
Published: April 2024

Enhancers are critical for regulating tissue-specific gene expression, and genetic variants within enhancer regions have been suggested to contribute to various cancer-related processes, including therapeutic resistance. However, the precise mechanisms remain elusive. Using a well-defined drug-gene pair, we identified an enhancer region for dihydropyrimidine dehydrogenase (DPD,
DPYD
gene) expression that is relevant to the metabolism of the anti-cancer drug 5-fluorouracil (5-FU). Using reporter systems, CRISPR genome edited cell models, and human liver specimens, we demonstrated
in vitro
and
vivo
that genotype status for the common germline variant (rs4294451; 27% global minor allele frequency) located within this novel enhancer controls
DPYD
transcription and alters resistance to 5-FU. The variant genotype increases recruitment of the transcription factor CEBPB to the enhancer and alters the level of direct interactions between the enhancer and
DPYD
promoter. Our data provide insight into the regulatory mechanisms controlling sensitivity and resistance to 5-FU.
Livestock abortion surveillance in Tanzania reveals disease priorities and importance of timely collection of vaginal swab samples for attribution
Authors: Lankester Felix , Kibona Tito J , Allan Kathryn J , de Glanville William , Buza Joram J , Katzer Frank , Halliday Jo E , Mmbaga Blandina T , Wheelhouse Nick , Innes Elisabeth A , Thomas Kate M , Nyasebwa Obed M , Swai Emanuel , Claxton John R , Cleaveland Sarah
Published: April 2024

Lack of data on the aetiology of livestock diseases constrains effective interventions to improve livelihoods, food security and public health. Livestock abortion is an important disease syndrome affecting productivity and public health. Several pathogens are associated with livestock abortions but across Africa surveillance data rarely include information from abortions, little is known about aetiology and impacts, and data are not available to inform interventions. This paper describes outcomes from a surveillance platform established in Tanzania spanning pastoral, agropastoral and smallholder systems to investigate causes and impacts of livestock abortion. Abortion events were reported by farmers to livestock field officers (LFO) and on to investigation teams. Events were included if the research team or LFO could attend within 72 hr. If so, samples and questionnaire data were collected to investigate (a) determinants of attribution; (b) patterns of events, including species and breed, previous abortion history, and seasonality; (c) determinants of reporting, investigation and attribution; (d) cases involving zoonotic pathogens. Between 2017–2019, 215 events in cattle (n=71), sheep (n=44), and goats (n=100) were investigated. Attribution, achieved for 19.5% of cases, was significantly affected by delays in obtaining samples. Histopathology proved less useful than PCR due to rapid deterioration of samples. Vaginal swabs provided practical and sensitive material for pathogen detection. Livestock abortion surveillance, even at a small scale, can generate valuable information on causes of disease outbreaks, reproductive losses and can identify pathogens not easily captured through other forms of livestock disease surveillance. This study demonstrated the feasibility of establishing a surveillance system, achieved through engagement of community-based field officers, establishment of practical sample collection and application of molecular diagnostic platforms.
Uncovering the BIN1-SH3 interactome underpinning centronuclear myopathy
Authors: Zambo Boglarka , Edelweiss Evelina , Morlet Bastien , Negroni Luc , Pajkos Mátyás , Dosztányi Zsuzsanna , Ostergaard Soren , Trave Gilles , Laporte Jocelyn , Gogl Gergo
Published: April 2024

Truncation of the protein-protein interaction SH3 domain of the membrane remodeling Bridging Integrator 1 (BIN1, Amphiphysin 2) protein leads to centronuclear myopathy. Here, we assessed the impact of a set of naturally observed, previously uncharacterized BIN1 SH3 domain variants using conventional
in vitro
and cell-based assays monitoring the BIN1 interaction with dynamin 2 (DNM2) and identified potentially harmful ones that can be also tentatively connected to neuromuscular disorders. However, SH3 domains are typically promiscuous and it is expected that other, so-far unknown partners of BIN1 exist besides DNM2, that also participate in the development of centronuclear myopathy. In order to shed light on these other relevant interaction partners and to get a holistic picture of the pathomechanism behind BIN1 SH3 domain variants, we used affinity interactomics. We identified hundreds of new BIN1 interaction partners proteome-wide, among which many appear to participate in cell division, suggesting a critical role of BIN1 in the regulation of mitosis. Finally, we show that the identified BIN1 mutations indeed cause proteome-wide affinity perturbation, signifying the importance of employing unbiased affinity interactomic approaches.
A new potential strategy for cutaneous squamous cell carcinoma treatment by generating serum-based antibodies from tumor-exposed mice
Authors: Liu Zheng
Published: April 2024

Current cancer treatment strategies continue to face significant challenges, primarily due to tumor relapse, drug resistance, and low treatment efficiency. These issues arise because certain tumor cells adapt to the host immune microenvironment and evade the immune system. This study presents a new cancer immunotherapy strategy using serum-based antibodies from mice exposed to mouse cutaneous squamous cell carcinoma (mCSCC). The experiment was conducted in three stages. In the first stage, mCSCC cells were isolated and expanded cultured from DMBA/TPA-induced mCSCC. In the second stage, these expanded tumor cells were injected into healthy mice to stimulate the production of anti-tumor antibodies. In the final stage, therapeutic serum was extracted from these healthy mice and reintroduced into the tumor-bearing mice. An ELISA assay was utilized to analyze the levels of p53, Bcl-xL, NF-κB, and Bax. The results showed that the serum treatment not only reduced tumor volume but also reversed changes in p53, Bcl-xL, NF-κB, and Bax. In conclusion, this study developed a new immunotherapeutic strategy for treating mCSCC. However, further research is needed to fully comprehend the mechanism of this serum treatment.
Generating specific homologous neutralizing-antibodies: a novel therapeutic strategy in cancer treatment
Authors: Zheng Liu
Published: April 2024

Current cancer therapeutic strategies still face great challenges especially due to tumor relapse, drug resistance, and low treatment efficiency. The reason is that some tumor cells are able to outsmart the host immune mechanisms and evade the immune system. In this study, using the mouse cutaneous squamous cell carcinoma (mCSCC) as an example, a new cancer immunotherapeutic strategy with homologous neutralizing-antibodies was established. The experiment is divided into three stages. In the first stage, mCSCC cells were isolated and cultured from DMBA/TPA-induced mCSCC. In the second stage, the expanded tumor cells were then injected into healthy mice in order to produce anti-tumor homologous neutralizing-antibodies. In the final stage, therapeutic serum was extracted from healthy mice and injected back into tumor mice. ELISA assay was used to analyze the levels of p53, Bcl-xL, NF-κB, and Bax. The findings demonstrated that the serum treatment reduced tumor volume while also reversing changes in p53, Bcl-xL, NF-κB, and Bax. In conclusion, a novel immunotherapeutic strategy was developed to treat mCSCC, although more study is required to fully understand the mechanism of this serum treatment.
Structural analysis of the dynamic ribosome-translocon complex
Authors: Lewis Aaron J. O. , Hegde Ramanujan S.
Published: April 2024

The protein translocon at the endoplasmic reticulum comprises the Sec61 translocation channel and numerous accessory factors that collectively facilitate the biogenesis of secretory and membrane proteins. Here, we leveraged recent advances in cryo-EM and structure prediction to derive insights into several novel configurations of the ribosome-translocon complex. We show how a transmembrane domain (TMD) in a looped configuration passes through the Sec61 lateral gate during membrane insertion; how a nascent chain can bind and constrain the conformation of ribosomal protein uL22; and how the translocon-associated protein (TRAP) complex can adjust its position during different stages of protein biogenesis. Most unexpectedly, we find that a large proportion of translocon complexes contains RAMP4 intercalated into Sec61’s lateral gate, widening Sec61’s central pore and contributing to its hydrophilic interior. These structures lead to mechanistic hypotheses for translocon function and highlight a remarkably plastic machinery whose conformations and composition adjust dynamically to its diverse range of substrates.
The mechanism of mammalian proton-coupled peptide transporters
Authors: Lichtinger Simon M , Parker Joanne L , Newstead Simon , Biggin Philip C
Published: April 2024

Proton-coupled oligopeptide transporters (POTs) are of great pharmaceutical interest owing to their promiscuous substrate binding site that has been linked to improved oral bioavailability of several classes of drugs. Members of the POT family are conserved across all phylogenetic kingdoms and function by coupling peptide uptake to the proton electrochemical gradient. Cryo-EM structures and alphafold models have recently provided new insights into different conformational states of two mammalian POTs, SLC15A1 and SLC15A2. Nevertheless, these studies leave open important questions regarding the mechanism of proton and substrate coupling, while simultaneously providing a unique opportunity to investigate these processes using molecular dynamics (MD) simulations. Here, we employ extensive unbiased and enhanced-sampling MD to map out the full SLC15A2 conformational cycle and its thermodynamic driving forces. By computing conformational free energy landscapes in different protonation states and in the absence or presence of peptide substrate, we identify a likely sequence of intermediate protonation steps that drive inward-directed alternating access. These simulations identify key differences in the extracellular gate between mammalian and bacterial POTs, which we validate experimentally in cell-based transport assays. Our results from constant-PH MD and absolute binding free energy (ABFE) calculations also establish a mechanistic link between proton binding and peptide recognition, revealing key details underpining secondary active transport in POTs. This study provides a vital step forward in understanding proton-coupled peptide and drug transport in mammals and pave the way to integrate knowledge of solute carrier structural biology with enhanced drug design to target tissue and organ bioavailability.
Tamizaje neonatal en Colombia: la experiencia de un programa privado en Bogotá
Authors: Bernal Jaime E. , Tamayo Martha Lucía , Briceño Ignacio , Benavides Escilda
Published: April 2024

Introducción. En Colombia, el primer programa de tamizaje neonatal, PREGEN, inició labores en el sector privado de Bogotá en 1988. En este artículo se presentan los resultados obtenidos en los últimos años, que, dada la carencia de estos estudios en el país, pueden servir para evaluar la frecuencia de aparición de los trastornos congénitos evaluados y estimar cuáles de ellos deben ser objeto de tamizaje neonatal a nivel nacional.Objetivos. Reportar los resultados del programa de tamizaje PREGEN entre el 2006 y el 2019.Materiales y métodos. Para este análisis se examinaron las bases de datos y otros documentos informativos de PREGEN para el periodo 2006-2019.Resultados. Uno de cada 164 recién nacidos tamizados en el programa PREGEN en Bogotá presentó una variante anormal de la hemoglobina y uno de cada 194 es portador de hemoglobina S. Los siguientes dos trastornos más frecuentes encontrados fueron la deficiencia de la enzima glucosa-6-fosfato deshidrogenasa (frecuencia 1:2.231) y el hipotiroidismo congénito (frecuencia 1:3.915).Conclusiones. Las hemoglobinopatías mostraron ser uno de los desórdenes monogénicos más comunes, seguidos por la deficiencia de glucosa-6-fosfato deshidrogenasa y el hipotiroidismo congénito. Se calcula que cerca de 400 millones de personas en el mundo están afectadas por la deficiencia de glucosa-6-fosfato deshidrogenasa, por lo cual es la enzimopatía más común en el mundo. Como ambos desórdenes son más frecuentes en poblaciones de origen africano y confieren algún grado de resistencia a la malaria, es de prever que su tamizaje debe ser de mayor importancia en las zonas con ancestros africanos en Colombia.
Seroprevalencia de Trypanosoma cruzi en niños de Veracruz, México: línea epidemiológica de base para un modelo de control fundamentado de la transmisión activa de la enfermedad de Chagas
Authors: Pérez-Sánchez Ernesto , Montiel-Cruz Raúl , Romero-Domínguez Eréndira , Pascacio-Bermúdez Griselda , Báez-Hernández Arturo , Díaz del Castillo-Flores Guadalupe , Correa-Morales Fabián , Vázquez-Prokopec Gonzalo , Manrique-Saide Pablo , Che-Mendoza Azael , Meneses-Ruiz Gabriela , López-Martínez Irma , Jesús Sánchez María
Published: April 2024

Introducción. En el 2021, la Secretaría de Salud de México y la Organización Panamericana de la Salud lanzaron una iniciativa para interrumpir la transmisión vectorial intradomiciliaria de Trypanosoma cruzi, fundamentada en la prevalencia de la enfermedad de Chagas en la población infantil. El estado mexicano de Veracruz fue el pionero de esta iniciativa.Objetivo. Estimar la seroprevalencia de infección por T. cruzi en menores de 15 años de localidades rurales de Veracruz, México.Materiales y métodos. Se identificaron ocho localidades prioritarias para la serología basal del municipio de Tempoal, Veracruz. Entre junio y agosto de 2017, se recolectaron muestras de sangre en papel filtro de 817 individuos para su tamizaje mediante un inmunoensayo enzimático de tercera generación. Los casos reactivos del tamizaje se confirmaron mediante pruebas de hemaglutinación indirecta, ensayo de inmunoabsorción ligado a enzimas e inmunofluorescencia indirecta en muestras de suero. Se calculó la seroprevalencia y su intervalo de confianza (IC) del 95 %.Resultados. En las localidades de Citlaltépetl, Cornizuelo, Cruz de Palma y Rancho Nuevo se confirmaron casos de la enfermedad de Chagas en menores de 15 años con una seroprevalencia de 1,9 % (IC 95 % = 1,12-3,16).Conclusiones. Los resultados indican que estas comunidades presentan transmisión reciente de T. cruzi y permiten establecer una línea epidemiológica de base para el diseño e implementación de un modelo dirigido a aquellas áreas geográficas con transmisión activa. Se espera que dicho modelo contribuya a la eliminación de la transmisión vectorial intradomiciliaria del tripanosomátido en México.
Cuando el Estado construye la barriada: efectos contradictorios de las políticas de vivienda social y de regularización del suelo en la ciudad de Tacna, Perú (2010-2016)
Authors:   ,   Pontificia Universidad Católica de Chile. Facultad de Arquitectura, Diseño y Estudios Urbanos, Abanto Sánchez Elizabeth Soledad
Published: April 2024

En la ciudad de Tacna la urbanización informal ha experimentado un ritmo persistente durante las últimas décadas, al punto que su crecimiento urbano es prácticamente sinónimo de expansión informal. Por lo tanto, esta investigación pretende indagar en los procesos que masificaron la informalidad en el acceso a la tierra, estableciendo la relación existente entre la política de vivienda social y de regularización de suelo con los diversos factores sociales, políticos e institucionales que favorecieron la proliferación de asentamientos informales en la ciudad de Tacna. Mediante un enfoque cualitativo a través de observaciones participantes y entrevistas a los diversos actores sociales; se pudo comprobar que la urbanización informal no solo deviene por vacíos legales, sino que principalmente ha sido promovida y acrecentada por el clientelismo político, la falta de relacionamiento inter-institucional y la permisividad de autoridades y funcionarios vinculados con el tráfico de terrenos.
Asociación entre los componentes de sarcopenia y sintomatología de fibromialgia en sujetos de la cohorte poblacional de Maule (Mauco)
Authors:   ,   Pontificia Universidad Católica de Chile. Facultad de Medicina, Tumani Karmy María Fernanda
Published: April 2024

Introducción: el síndrome de fibromialgia (FM) se caracteriza por presentar dolor crónico generalizado, en donde existe neuro-inflamación. La disminución de masa libre de grasa (MLG) se ha asociado a mayor presencia de marcadores inflamatorios, respectivamente. A la fecha, no se ha asociado la MLG ni fuerza muscular con intensidad de síntomas en estos sujetos con fibromialgia. Objetivo: evaluar la asociación entre los componentes de la sarcopenia y sintomatología en FM. Metodología: se analizaron los datos de una submuestra de la cohorte poblacional de Maule. Resultados: se observó una correlación inversa entre fuerza muscular e IMLG con síntomas en FM. Además se observó una asociación entre IMLG e Intensidad de dolor. Conclusión: existe una correlación entre los componentes de la sarcopenia e intensidad de síntomas en FM.
La libertad como despliegue y autoconfiguración de la persona humana, al modo de la dinámica trinitaria del amor, en Edith Stein : elaboración teológico-sistemática a partir del corpus steiniano
Authors:   , Bello D. Haddy
Published: April 2024

La presente investigación sistematiza la idea de libertad a partir de la vida y obra de Edith Stein, desde la comprensión trinitaria de la libertad como fundamento de la autoconfiguración humana. Se ha escogido a Stein por ser una autora integral y por su capacidad de tender puentes de diálogo entre los saberes. La temática de la tesis se desarrolló a partir de tres objetivos específicos: 1) El abordaje crítico del corpus steiniano, descubriendo la estructura de pensamiento y los nudos problemáticos esenciales presentes en toda la obra. 2) La profundización teológica del concepto de libertad. 3) La relevancia teológica de un estudio sobre la libertad humana a imagen de la libertad divina. De entre los frutos de esta investigación se puede destacar el aspecto trinitario que configura la libertad humana. Esto es, la libertad como experiencia vivida en relación, cuya fuerza vital es el Amor. Amor que permite la unión con Dios mediada por el Espíritu divino, que eleva al ser humano a la mutua entrega. Esa es la conquista del ser, auto-conquista que Dios quiere y espera de nosotros y que se alcanza mediante la experiencia relacional auxiliada por la gracia. Es decir, el modelo de la libertad es la Trinidad.
Análise bibliométrica sobre Simbiose Industrial: mapeamento da literatura científica
Authors: Nogueira Tarcísio da Cunha , Barros Adriano David Monteiro de
Published: April 2024

Como um dos principais facilitadores da Economia Circular (EC), a Simbiose Industrial (SI) tem como objetivo promover a eficiência na utilização de recursos e minimizar o desperdício dentro de uma rede de indústrias. O número de publicações sobre SI tem aumentado consideravelmente, refletindo tanto o interesse dos pesquisadores pelo tema quanto a expansão da SI para novas áreas de pesquisa. Este estudo propõe uma análise bibliométrica abrangente, mapeando os principais tópicos, autores e países abordados na literatura sobre o tema. Essa análise contribui para a compreensão e identificação dos temas centrais, bem como para o reconhecimento de autores e países que desempenham um papel significativo nesse campo de pesquisa.
Sign Language Classifier based on Machine Learning
Authors:   Department of Automation, Technical University of Cluj Napoca, Ge. Bariţiu 26-28, Cluj-Napoca, Romania, Avram Camelia , Păcurar Laura – Flavia , Radu Dan
Published: April 2024

Sign language represents an efficient way for individuals with hearing impairments to communicate. We propose a sign recognition system into which several tools are integrated to help with the image pre-processing part. By doing so, a machine learning model was developed that does not require a lot of processing power because instead of using the images themselves, it uses extracted data from them to connect this model to a mobile interface that the users will use to recognise signed letters successfully. The communication between the client and the model is sustained through a local server.
Effect of TIBW anti-wear coating on cutting tools for milling of nickel alloys on tool wear and integrity of state of the technological surface layer
Authors:   Rzeszów University of Technology, Faculty of Mechanical Engineering and Aeronautics, al. Powstańców Warszawy 8, 35-959 Rzeszów, Poland, Habrat Witold , Tymczyszyn Jarosław , Skroban Anna , Karkalos Nikolaos
Published: April 2024

In the article, research was carried out to determine the impact of the TiBW anti-wear coating on the operational properties of cutting tools for machining nickel alloys. The dynamics of tool wear were determined based on changes in the components of the total cutting force, microscopic observation of wear on the flank surface, and observation of wear based on SEM images. The condition of the technological surface layer was also determined in the form of changes in the microstructure morphology and hardening of the surface layer. The research was compared to a reference tool with the same geometry with an AlTiN coating. It was shown, among other things, that TiBW coatings can be used successfully for cutting tools for machining nickel alloys, and that the wear dynamic is similar to those of tools with the AlTiN coating. The analyses confirmed the significant thermomechanical impact of the cutter during machining, manifested by chipping and a tendency to strengthen the processed material. Based on observations of the microstructure of the surface layer after processing, it was shown that the thermal conductivity of the TiBW coating may be lower than that of the AlTiN coating, which is reflected in the different depths of the thermomechanical interaction zones.
A Frame Work for Development of Hybrid-teaching Factory (H-TEFA) Model on Virtual Lab application
Authors: Amiruddin Erwin Gatot , Gani Hamsu Abdul , Syafar Faisal
Published: April 2024

The core of Industry 4.0 is the extensive use of Information System in organizational business processes. The competency of System Analysis and Design is required by companies as an expert in Information System development. UNITAMA, a higher education institution, is developing a program of study in Information Systems that produces competent professionals with a discipline in Analysis and Information System Design. The university will strengthen student competencies through a collaborative approach between the learning process and IDUKA. The type of research is Research & Development (R&D) research so that the process of developing virtual learning media technology media for the Hybrid Teaching Factory (H-TEFA) model is directed and systematic, so in this research and development using the ADDIE development model which consists of five development stages (analysis, design, product manufacturing, implementation and evaluation). The Virtual Lab is a modern learning method based on the Learning Management System (LMS) that provides students with more dynamic and customized educational materials for practical learning. The Virtual Lab UNITAMA is the development of a practical learning method designed and adapted to the needs of the Analysis and Information System Design course based on the IDUKA Information System, utilizing web-based IT technology that allows learning to take place remotely, not limited to the classroom and specific hours. The model of collaboration between teachers, students, and IDUKA in the Analysis and Information System Design course is enabled by the rapid development of technology and information systems in the era of Industry 4.0, using e-learning/LMS systems that are integrated with Virtual Lab. The Link & Match policy between the education sector and IDUKA is expected to improve the competencies of graduates and align them with IDUKA's specific needs.
Assessment of Green Manure Crops and their Impacts on Mineralizable Nitrogen and Changes of Nutrient Contents in the Soil
Authors: Hlaing Thidar , Moe Kyi , Kyaw Ei Han , Ngwe Kyaw , Hlaing Myat Moe , Oo Htay Htay
Published: April 2024

To evaluate the green manure crops those can promote soil properties and the ability of nitrogen (N) mineralization in paddy soil, a pot experiment was conducted at the Department of Agronomy, Yezin Agricultural University, Naypyidaw, Myanmar from April to August 2022. The experimental design was a randomized complete block design with three replications. Ten green manure crops were sown as treatments: soybean (Glycine max (L.) Merr), green gram (Vigna radiata L. Wildzek.), black gram (Vigna mungo L. Hepper.), cowpea (Vigna catjang), cowpea white (Vigna unguiculata (L.) Walp.), lab lab bean (Lablab purpureus (L.) Sweet.), mayflower bean (Phaseolus vulgaris L.), rice bean (Vigna umbellata), sunn hemp (Crotalaria juncea L.), and dhaincha (Sesbania bispinosa (Jacq.)). At the flowering stage, various green manures were incorporated into the soil, and their growth characters were measured along with the mineralizable N, total N, phosphorus (P2O5), and potassium (K2O) contents of the soil. The results indicated that rice bean, sunn hemp, and dhaincha had higher shoot and root length, shoot and root fresh weight, and dry weight compared to other varieties. In addition, they contain a higher percentage of total N content and total P2O5, and consequently, its C:N ratio was lower. After incorporating green manures into the soil, the mineralizable N increased gradually from 0 weeks to 10 weeks and then, the nutrient values decreased. Among green manures, sunn hemp, dhaincha, and rice bean were found to have higher mineralizable N (%) and applicable mineralized N than others. In conclusion, the incorporation of green manures into the soil improves the N, P2O5, and K2O contents of the soil, along with the mineralizable N content. Among green manure crops, dhaincha, rice bean, and sunn hemp were superior to other varieties due to higher biomass yield, mineralizable N (%), and chemical compositions, especially total N content.
Applications of Molecular Marker Implementation for Enhanced Oilseed Breeding through Marker-Assisted Selection (Mas)
Authors: Tharun Pantla Sai , Talekar Nilesh , Akkati Vineeth Reddy
Published: April 2024

Oilseed crops are fundamental for various industrial and food purposes, necessitating advancements in breeding strategies to meet growing demands. Molecular markers and Marker-Assisted Selection (MAS) have emerged as powerful tools in oilseed crop improvement. This review explores the diverse applications of molecular markers and MAS in oilseed crops, highlighting their significance in enhancing breeding efficiency and genetic gains. The primary aim of this review is to provide a comprehensive overview of the application of molecular markers and MAS in oilseed crop breeding programs. Specifically, it aims to synthesize existing literature and case studies to elucidate the methodologies, advancements, and outcomes associated with the integration of molecular markers and MAS in oilseed crop improvement. The review highlights significant advancements in the application of molecular markers and MAS in oilseed crop breeding. Molecular markers have been extensively utilized for trait mapping, genetic diversity analysis, and selection of desirable genotypes with traits such as high oil content, disease resistance, and abiotic stress tolerance. Integration with conventional breeding methods has facilitated the development of elite oilseed crop varieties with improved agronomic performance and stress resilience. In conclusion, molecular markers and MAS represent valuable tools for accelerating oilseed crop breeding programs. Their integration has led to increased breeding efficiency, precision, and genetic gains. However, challenges such as marker validation, cost-effectiveness, and trait complexity remain to be addressed. Future research efforts should focus on refining marker technologies, enhancing trait mapping studies, and promoting the adoption of MAS in oilseed crop breeding to ensure sustainable production and global food security.
Hepato-protective Effect of Costus afer (Okpete) Juice Extract on Alcohol-induced Liver Toxicity in Adult Female Wistar Rats
Authors: N. L. Okwuanga, , M. O Onyewuchi, , C. A. Mbah, , E. C. Okafor, , S. N. Ejikeme, , E. K. Nwanama, , R. C. Nwachukwu,
Published: April 2024

Background: The oral intake of alcohol has become a widespread concern due to its high risk to body health. Therefore, our purpose in this study was to reveal the antioxidant efficacies of natural Costus's afer stem juice extract on hepatotoxicity induced by ethanol in adult female wistar rats.
Methods: We examined the impacts of liver toxicity, were the experimental animals were given 1ml of 10% ethanol daily for 21 days, thereafter, C. afer was administered to evaluate its ameliorative effect in the female albino wistar rats orally treated with C. afer juice extract (200 and 400 mg/kg) for 7days. The rats were divided into four (4) groups; Group A served as the control group, which was given rat chow and water only. Groups B, C and D were given 1ml of 10% ethanol. Afterwards, groups C and D were treated with 200 and 400 mg/kg using 1ml and 2ml of the juice extract of C. afer, respectively. A liver function test and histological analysis were carried out.
Results: The results showed that treatment with C. afer after the oral consumption of ethanol caused elevation in serum liver function parameters (alanine transferases, aspartate transaminase, and alkaline phosphate), which is significant compared to the control group. There was also a slight restoration in histopathological changes in the liver, as revealed by decreased areas of inflammation.
Conclusion: The therapeutic efficiency of C. afer juice extract could be due to traces of anti-inflammatory properties and the ROS-scavenging agent. Our findings prove that the elevation of liver function markers by C. afer enables hepatic tissue to suppress inflammatory and oxidative mechanisms, resulting in enhanced liver structure and function. Therefore, C. afer extract is a protective and therapeutic supplement against toxic agents.
Successful Intestinal Blood Flow Evaluation Using Indocyanine Green Fluorescent Imaging in a Case of Small Intestine Strangulation
Authors: Matsune Yusuke , Aoki Takeshi , Tashiro Yoshihiko
Published: April 2024

Introduction

The assessment of intestinal blood flow using indocyanine green (ICG) fluorescence imaging is useful in ischemic bowel disease because it renders blood flow visible. Strangulated small intestine is a common postoperative complication requiring massive bowel resection, which can cause short bowel obstruction (SBO), a malabsorptive condition. Here, we report a successful case of preserving an ischemic intestinal segment while avoiding SBO based on the gap between the macroscopic findings and the ICG fluorescence imaging assessment.

Case presentation

A 46-year-old Japanese female patient who underwent an abdominal total hysterectomy and bilateral salpingo-oophorectomy with para-aortic lymphadenectomy due to small round cells of the left ovary received a diagnosis of strangulated small intestine 1 month postoperatively. Macroscopic examination during the laparotomy revealed a strangulated small intestine with severe edema and dark red discoloration. However, this part of the bowel was preserved during surgery because the two-time administration of ICG solution revealed adequate perfusion.

Conclusion

This report reveals the effectiveness of ICG fluorescence imaging in intraoperative intestinal perfusion and its role in avoiding unnecessary massive resections. Combining these modalities may be effective for intraoperative bowel assessment; however, more accurate criteria and algorithms for evaluating blood flow and bowel perfusion should be established.
Wedge test of carbon‐nanotube‐reinforced epoxy adhesive joints
Authors: Yu Suzhu , Tong Min Nah , Critchlow Gary
Published: December 2008

Epoxy adhesives reinforced with carbon nanotubes (CNTs) were developed. The distribution of the CNTs in the epoxy matrix was observed with transmission electron microscopy. Joints were formed by unclad 2024‐T3 aluminum adherents bonded with the CNT‐filled epoxy adhesives. The durability of the joints was studied with a wedge test under water at 60°C. The addition of CNTs to the epoxy greatly improved the adhesive joint durability. The initial crack length of the joint with 1 wt % CNTs, which was obtained before the wedge specimen was put into water, was only about 7% of that with neat epoxy. After immersion of the specimens in 60°C water, the joint with neat epoxy failed after 3 h, but all of the joints adhered with different fractions of CNTs were still bound together after the experimental time of 90 h. The significant enhancement by CNTs of the adhesive joint durability was mainly attributed to the high mechanical properties of the CNTs and their ability to resist water. Nevertheless, the experimental results also reveal that the durability of the joints showed an optimum value at approximately 1 wt % CNTs, beyond which a decrease in the property was observed. In addition, the failure mechanism of the joints was also investigated in terms of interfacial failure and cohesive failure. Cohesive dominated failure was found for the joint bonded with 1 wt % CNT‐filled epoxy. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Comparative study on the technological properties of latex and natural rubber from Hancornia speciosa Gomes and Hevea brasiliensis
Authors: Malmonge José Antonio , Camillo Egiane Carla , Moreno Rogério Manoel Biagi , Mattoso Luiz Henrique Capparelli , McMahan Colleen Marie
Published: December 2008

This work reports a systematic comparative study of the technological properties of natural lattices and rubbers extracted from Hancornia speciosa Gomes and Hevea brasiliensis [(Willd. ex Adr. de Juss.) Muell.‐Arg.] (clone RRIM 600) trees from 11 collections in Brazil throughout 2004. Natural rubber latex particle sizes and distributions were quite similar with an average diameter around 1 μm. Molecular weight, Wallace plasticity, and Mooney viscosity values were approximately the same for both rubbers. Fourier transform infrared spectroscopy peaks characteristic of natural rubber were observed for both Hancornia and Hevea. The measured differences in technological properties included lower values for Hancornia dry rubber content, % ash, % nitrogen, and plasticity retention index but higher value for acetone extract. Interestingly, nitrogen and protein content were much lower in Hancornia, suggesting that it may have important applications in nonallergic rubber uses. This represents the first report of lacticifer‐produced low‐protein natural rubber. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Comparisons of weathering performance of two automotive refinish coatings: A case study
Authors: Yari H. , Mohseni M. , Ramezanzadeh B.
Published: December 2008

The aim of this study was to compare the weathering performance of two commonly refinish coatings used in a domestic car manufacturer based on polyurethane (PU) and acid‐catalyzed alkyd‐melamine resins. The replacement of the alkyd‐melamine refinish with the PU system was shown to largely lower the reported fading behavior of the monocoat system. For better comparison between the refinish coatings, an original equipment manufacturers' (OEM) topcoat, cured at production line, was also used. Different characterization methods including DSC, atomic force microscopy, thermo gravimetric analysis, DMTA, and Fourier transform infrared spectroscopy were performed to elucidate the changes observed in the optical, mechanical, and weathering performance of studied coatings. It was found that the main reason for the inferior behavior of the acid‐catalyzed coatings compared with that of the PU and OEM was due to its low crosslinking density. The poor weathering resistance of the former coatings was attributed to its incomplete curing reaction and therefore, to its immatured film formation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Multiwalled carbon nanotube nucleated crystallization behavior of biodegradable poly(butylene succinate) nanocomposites
Authors: Pramoda K. P. , Linh N. T. T. , Zhang Chao , Liu Tianxi
Published: December 2008

Poly(butylene succinate) (PBS) nanocomposites with multiwalled carbon nanotubes (MWNTs) prepared by melt compounding were studied for the effect of MWNT dispersion on the modulus and crystallization kinetics. The nucleating effect of the addition of 0.1 wt % MWNT to PBS was clearly demonstrated. Differential scanning calorimetry nonisothermal crystallization studies showed a clear decrease in the half‐time of crystallization with increasing MWNT content in PBS/MWNT nanocomposites. It was observed with the Ozawa method that the Ozawa parameter values for the nanocomposites were lower than those for neat PBS, and this indicated that the crystal morphology was different. The storage modulus of the nanocomposites increased about 23% with the addition of only 0.1% MWNT in comparison with neat PBS, whereas the glass‐transition temperature was unaltered. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Friction and wear properties of polyimide matrix composites reinforced with short basalt fibers
Authors: Zhang Xinrui , Pei Xianqiang , Wang Qihua
Published: December 2008

Short basalt fiber (BF) reinforced polyimide (PI) composites were fabricated by means of compression‐molding technique. The friction and wear properties of the resulting composites sliding against GCr15 steel were investigated on a model ring‐on‐block test rig under dry sliding conditions. The morphologies of the worn surfaces and the transfer films that formed on the counterpart steel rings were analyzed by means of scanning electron microscopy. The influence of the short BF content, load, and sliding speed on the tribological behavior of the PI composites was examined. Experimental results revealed that the low incorporation of BFs could improve the tribological behavior of the PI composites remarkably. The friction coefficient and wear rate decreased with increases in the sliding speed and load, respectively. The transfer film that formed on the counterpart surface during the friction process made contributions to reducing the friction coefficient and wear rate of the BF‐reinforced PI composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Novel hollow‐fiber anion‐exchange hybrid membranes: Preparation and characterization
Authors: Xu Tongwen , Lu Fangfang , Wu Yonghui
Published: December 2008

To develop ion‐exchange membranes for application in severe conditions, such as those with high temperatures, strongly oxidizing environments, or organic solvents, new hollow‐fiber anion‐exchange hybrid membranes were prepared by the immersion of brominated poly(2,6‐dimethyl‐1,4‐phenylene oxide) base hollow fibers in a tetraethoxysilane–ethanol solution followed by sol–gel and quaternary amination. Compared to conventional polymeric charged membranes, the prepared hybrid membranes were higher in both thermal and dimensional stabilities. The results suggest that tetraethoxysilane concentration was an important factor affecting the membrane's intrinsic properties. When the tetraethoxysilane concentration was in the range 15–45%, the final hollow‐fiber anion‐exchange hybrid membranes had an ion‐exchange capacity of 1.9–2.0 mmol/g, a water uptake of.83–1.23 g of water/g of dry weight, and a dimensional change ratio of 13–18%. An evaluation on the membranes' separation performances is underway. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Yield and physicochemical properties of EPS from Halomonas sp. strain TG39 identifies a role for protein and anionic residues (sulfate and phosphate) in emulsification of n‐hexadecane
Authors: Gutierrez Tony , Morris Gordon , Green David H.
Published: December 2008

In this study, we investigated the yield and physicochemical properties of the high molecular weight extracellular polymeric substance (HMW–EPS) produced by Halomonas sp. strain TG39 when grown on different types and ratios of substrates. Glucose (1% w/v) and a peptone/yeast extract ratio of 5.1 (0.6% w/v final concentration) yielded an EPS fraction (HMW‐glucose) exhibiting the highest anionic activity (20.5) and specific emulsifying activity (EI24 = 100%) compared to EPS produced by cells grown on mannitol, sucrose, malt extract or no carbon source. The HMW–EPS fractions were capable of binding ≈255–464 mg of methylene blue (MB) per gram of EPS, which represents the highest reported binding of MB by a bacterial EPS. A comparative evaluation of these properties to those of commercial hydrocolloids indicated that the combined effect of protein and anionic residues of the HMW–EPS contributed to its ability to emulsify n‐hexadecane. Liquid chromatography revealed the HMW‐glucose EPS to be a heterogeneous polymer with a polydispersity index of 1.8. This work presents evidence of a correlation between the anionic nature and protein content of bacterial EPS with its emulsifying qualities, and identifies EPS produced by strain TG39 as a high MB‐binding bacterial sorbant with potential biotechnological application. Biotechnol. Bioeng. 2009;103: 207–216. © 2008 Wiley Periodicals, Inc.