bluuebunny/crossref_metadata_2025 huggingface dataset:
Comprehensive Evaluation for Cold Tolerance in Wucai (Brassica campestris L.) by the Performance Index on an Absorption Basis (PIabs)
Authors: Dai Yun , Yuan Lingyun , Zhang Shujiang , Wang Jie , Xie Shilei , Zhao Mengru , Chen Guohu , Sun Rifei , Wang Chenggang
Published: January 2019

Wucai is a biannual leafy vegetable that is more sensitive to cold than most Brassicaceae vegetables. Here, phenotypic differences in wucai were investigated to identify those genotypes with high cold tolerance at low temperature, which could allow their cultivation in cold climates. In all, on the basis of PIabs, 20 wucai genotypes (10 lower PIabs and 10 higher PIabs) were selected from a collection of 124 genotypes. Both W16-13 and SW-3 (higher PIabs) and the LS-6 and W15-16 (lower PIabs) were screened from the 20 wucai genotypes according to several key plant physiological traits: net photosynthetic rate, electrolyte leakage, chilling injury index, specific leaf area, malondialdehyde contents, and PIabs. To further verify the reliability of PIabs, four genotypes were grown under low temperature gradient conditions and their morphological indexes, chlorophyll content, total antioxidant capacity, fluorescence transients (OJIP transients), leaf cell ultrastructure, and gene expression were measured. These indicators strongly demonstrated that the W16-13 and SW-3, which had higher PIabs, possessed higher resistance to cold stress, while both LS-6 and W15-16 were sensitive to cold. As this study shows, the easily measured performance index, PIabs, could be applied to wucai genotypes to screen for one or more varieties characterized by higher cold tolerance.
Feather Pecking and Cannibalism in Non-Beak-Trimmed Laying Hen Flocks—Farmers’ Perspectives
Authors: Kaukonen Eija , Valros Anna
Published: January 2019

Pecking-related problems are common in intensive egg production, compromising hen welfare, causing farmers economic losses and negatively affecting sustainability. These problems are often controlled by beak trimming, which in Finland is prohibited. An online questionnaire aimed to collect information from farmers about pecking-related problems in Finnish laying hen flocks, important risk factors and the best experiences to prevent the problems. Additionally, the farmers’ attitudes towards beak trimming were examined. We received 35 responses, which represents about 13% of all Finnish laying hen farms with ≥300 laying hens. The majority of respondents stated that a maximum of 5–7% incidence of feather pecking or 1–2% incidence of cannibalism would be tolerable. The majority of respondents (74%) expressed that they would definitely not use beak-trimmed hens. Only two respondents indicated that they would probably use beak-trimmed hens were the practice permitted. Among risk factors, light intensity earned the highest mean (6.3), on a scale from 1 (not important) to 7 (extremely important). Other important problems included those that occurred during rearing, feeding, flock management and problems with drinking water equipment (mean 5.9, each). The most important intervention measures included optimal lighting and feeding, flock management, and removing the pecker and victim. Concluding, Finnish farmers had strong negative attitudes towards beak trimming. The study underlines the importance of flock management, especially lighting and feeding, in preventing pecking problems and indicates that it is possible to incorporate a non-beak-trimming policy into sustainable egg production.
Effects of Graphene Nanoplatelets and Multiwall Carbon Nanotubes on the Structure and Mechanical Properties of Poly(lactic acid) Composites: A Comparative Study
Authors: Batakliev Todor , Petrova-Doycheva Ivanka , Angelov Verislav , Georgiev Vladimir , Ivanov Evgeni , Kotsilkova Rumiana , Casa Marcello , Cirillo Claudia , Adami Renata , Sarno Maria , Ciambelli Paolo
Published: January 2019

Poly(lactic acid)/graphene and poly(lactic acid)/carbon nanotube nanocomposites were prepared by an easy and low-cost method of melt blending of preliminary grinded poly(lactic acid) (PLA) with nanosized carbon fillers used as powder. Morphological, structural and mechanical properties were investigated to reveal the influence of carbon nanofiller on the PLA–based composite. The dependence of tensile strength on nanocomposite loading was defined by a series of experiments over extruded filaments using a universal mechanical testing instrument. The applying the XRD technique disclosed that compounds crystallinity significantly changed upon addition of multi walled carbon nanotubes. We demonstrated that Raman spectroscopy can be used as a quick and unambiguous method to determine the homogeneity of the nanocomposites in terms of carbon filler dispersion in a polymer matrix.
A High-Power and Highly Efficient Semi-Conductor MOPA System for Lithium Atomic Physics
Authors: Wu Hao , Zhu Hongbo , Zhang Jianwei , Peng Hangyu , Qin Li , Ning Yongqiang
Published: January 2019

A compact and highly efficient 670.8-nm semi-conductor master oscillator power amplifier (MOPA) system, with a unique optical design, is demonstrated. The MOPA system achieves a continuous-wave (CW) output power of 2.2 W, which is much higher than commercial products using semi-conductor devices. By comparing solid state lasers and dye lasers, higher wall-plug efficiency (WPE) of 20 % is achieved. Our developed laser system also achieves spectral line-width of 0.3 pm (200 MHz) and mode-hop free tuning range of 49 pm (32.6 GHz), which is very suitable for experiments of lithium atomic physics at several-watt power levels, such as Bose-Einstein condensation (BEC) and isotope absorption spectroscopy.
Biodegradation of Pyrethroids by a Hydrolyzing Carboxylesterase EstA from Bacillus cereus BCC01
Authors: Hu Wei , Lu Qiqi , Zhong Guohua , Hu Meiying , Yi Xin
Published: January 2019

Microbial degradation has been considered as a rapid, green, and cost-effective technique to reduce insecticide pollutions in a contaminated environment. However, the instability and low efficacy of non-indigenous microorganisms hampers their further exploitation when being introduced into a real environmental matrix. In order to overcome the restriction that these functional microorganisms are under, we investigated the optimal conditions to improve the pyrethroid-degrading ability of one previously isolated bacterium Bacillus cereus BCC01, where 9.6% of the culture suspension (with cell density adjusted to OD600 = 0.6) was inoculated into 50 mL media and cultivated at pH 8 and 30 °C, and its metabolic pathway was illuminated by analyzing the main metabolites via gas chromatography mass spectrometry (GC-MS). Most importantly, a key pyrethroid-hydrolyzing carboxylesterase gene estA was identified from the genomic library of strain BCC01, and then expressed in Escherichia coli BL21 (DE3). After purification, the recombinant protein EstA remained soluble, displaying high degrading activity against different pyrethroids and favorable stability over a wide range of temperatures (from 15 °C to 50 °C) and pH values (6.5–9). Therefore, the EstA-associated biodegradation of pyrethroids was determined, which could provide novel insights to facilitate the practical application of B. cereus BCC01 in the microbial detoxification of pyrethroid contamination.
An Agile Approach to Improve the Usability of a Physical Telerehabilitation Platform
Authors: Pilco Hennry , Sanchez-Gordon Sandra , Calle-Jimenez Tania , Pérez-Medina Jorge , Rybarczyk Yves , Jadán-Guerrero Janio , Maldonado César , Nunes Isabel
Published: January 2019

The goal of a telerehabilitation platform is to safely and securely facilitate the rehabilitation of patients through the use of telecommunication technologies complemented with the use of biomedical smart sensors. The purpose of this study was to perform a usability evaluation of a telerehabilitation platform. To improve the level of usability, the researchers developed and proposed an iterative process. The platform uses a digital representation of the patient which duplicates the therapeutic exercise being executed by the patient; this is detected by a Kinect camera and sensors in real time. This study used inspection methods to perform a usability evaluation of an exploratory prototype of a telerehabilitation platform. In addition, a cognitive workload assessment was performed to complement the usability evaluation. Users were involved through all the stages of the iterative refinement process. Usability issues were progressively reduced from the first iteration to the fourth iteration according to improvements which were developed and applied by the experts. Usability issues originally cataloged as catastrophic were reduced to zero, major usability problems were reduced to ten (2.75%) and minor usability problems were decreased to 141 (38.74%). This study also intends to serve as a guide to improve the usability of e-Health systems in alignment with the software development cycle.
Makers Marks: Capturing, Preserving, and Sharing the Sounds of Glassmaking
Authors: Naas Lisa , Faleris David
Published: January 2019

The Makers Marks Collaborative, an international team of glass artists, visual designers, composers, and engineers, embarked on a project together from 2015–2016 to use the glassmaking studio as a staging ground for interdisciplinary, collaborative making. The team aimed to capture and preserve the sounds of traditional studio glassmaking, and then to share them outside the workshop domain through digital technologies and glass art objects. The goal was also to fulfill a public engagement grant from the Royal Academy of Engineering to highlight the engineering through the art and the engineers’ vision within the art making. The team recorded and isolated the unique sounds of the glassblowing process and its studio environment, and then used the resulting digital sound collection as the foundation for developing artistic outputs: a virtual instrument library, a glass object-instrument of performance, a series of glass objects translating selected virtual instruments, and a music composition. They questioned the nature and materiality of glass through dialogue between media and conversation among team members, while exploring the practice-based research question: “How can we embed our recorded sounds of the glassmaking process back into the glass itself?” This paper focuses on the collaborative, interdisciplinary making process of the team, the project outputs, and the metaphorical language that was a key process facilitation tool.
Race, Depression, and Financial Distress in a Nationally Representative Sample of American Adults
Authors: Assari Shervin
Published: January 2019

Background: Although depression and financial distress are correlated, this association may differ for demographic groups, particularly based on race. Aim: Using a national sample of American adults, this study tested whether the association between Major Depressive Episode (MDE) and financial distress differs between African Americans and Whites. Methods: The National Survey of American Life (NSAL), 2003, enrolled 3570 African American and 891 Non-Hispanic White American adults. Demographic data (age and gender), socioeconomic position (SEP; i.e., education, employment, marital status, and income), financial distress, and 12-month MDE were measured. Logistic regression was used for data analysis. Results: In the pooled sample, 12-month MDE was associated with higher odds of financial distress, above and beyond objective SEP measures. We found MDE by race interaction on financial distress, suggesting stronger association between MDE and financial distress among African Americans, compared to Whites. Conclusions: The link between MDE and financial distress depends on race. The financial needs of African Americans with depression should be addressed. Depression screening is also needed for African Americans with financial distress.
Calcium Ethoxide as Consolidant for Porous Limestones: Influence of the Solvent
Authors: Zuena Martina , Zendri Elisabetta , Costa Dória , Delgado-Rodrigues José , El Habra Naida , Tomasin Patrizia
Published: January 2019

Calcium ethoxide nanosuspension, a consolidating product developed during the European Nanomatch project, is here modified by adding two different solvents, 2-butanol and n-butylacetate, chosen for their different boiling points with respect to ethanol, the solvent employed in a previous work to dilute the original product. Fourier transform infrared spectroscopy (µFT-IR) was used to understand how the presence of these new solvents can influence the kinetics of the carbonation process and the pathway reaction. Furthermore, coatings derived from nanosuspensions were maintained for specific time intervals at controlled relative humidity conditions (RH = 50% and RH = 90%); the formed mineralogical phases were characterized by µFT-IR and X-ray diffraction (XRD). Results indicate that the used solvents can influence the kinetic and reaction pathways, while the phases formed at the end of the carbonation process are influenced by both solvents and RH conditions. The effectiveness of calcium ethoxide based product diluted in 2-butanol and n-butylacetate as limestone consolidants was evaluated with drilling resistance measurement system (DRMS) and ultrasound pulse velocity (UPV). The impact on color coordinates was also assessed. The results were compared with those obtained with the same product diluted in ethanol and a commercial nanolime. The use of these solvents gave different and better results in terms of efficacy.
Recent Developments in Sonic Crystals as Barriers for Road Traffic Noise Mitigation
Authors: Fredianelli Luca , Del Pizzo Lara , Licitra Gaetano
Published: January 2019

Noise barriers are the most widespread solution to mitigate noise produced by the continuous growth of vehicular traffic, thus reducing the large number of people exposed to it and avoiding unpleasant effects on health. However, conventional noise barriers present the well-known issues related to the diffraction at the edges which reduces the net insertion loss, to the reflection of sound energy in the opposite direction, and to the complaints of citizens due to the reduction of field of view, natural light, and air flow. In order to avoid these shortcomings and maximize noise abatement, recent research has moved toward the development of sonic crystals as noise barriers. A previous review found in the literature was focused on the theoretical aspects of the propagation of sound through crystals. The present work on the other hand reviews the latest studies concerning the practical application of sonic crystal as noise barriers, especially for road traffic noise mitigation. The paper explores and compares the latest developments reported in the scientific literature, focused on integrating Bragg’s law properties with other mitigation effects such as hollow scatterers, wooden or recycled materials, or porous coating. These solutions could increase the insertion loss and frequency band gap, while inserting the noise mitigation action in a green and circular economy. The pros and cons of sonic crystal barriers will also be discussed, with the aim of finding the best solution that is actually viable, as well as stimulating future research on the aspects requiring improvement.
An Investigation into Healthcare-Data Patterns
Authors: Boddy Aaron , Hurst William , Mackay Michael , El Rhalibi Abdennour , Baker Thar , Montañez Casimiro A. Curbelo
Published: January 2019

Visualising complex data facilitates a more comprehensive stage for conveying knowledge. Within the medical data domain, there is an increasing requirement for valuable and accurate information. Patients need to be confident that their data is being stored safely and securely. As such, it is now becoming necessary to visualise data patterns and trends in real-time to identify erratic and anomalous network access behaviours. In this paper, an investigation into modelling data flow within healthcare infrastructures is presented; where a dataset from a Liverpool-based (UK) hospital is employed for the case study. Specifically, a visualisation of transmission control protocol (TCP) socket connections is put forward, as an investigation into the data complexity and user interaction events within healthcare networks. In addition, a filtering algorithm is proposed for noise reduction in the TCP dataset. Positive results from using this algorithm are apparent on visual inspection, where noise is reduced by up to 89.84%.
Dual-Band Monopole Antenna for RFID Applications
Authors: Ojaroudi Parchin Naser , Jahanbakhsh Basherlou Haleh , Abd-Alhameed Raed A. , Noras James M.
Published: January 2019

Over the past decade, radio-frequency identification (RFID) technology has attracted significant attention and become very popular in different applications, such as identification, management, and monitoring. In this study, a dual-band microstrip-fed monopole antenna has been introduced for RFID applications. The antenna is designed to work at the frequency ranges of 2.2–2.6 GHz and 5.3–6.8 GHz, covering 2.4/5.8 GHz RFID operation bands. The antenna structure is like a modified F-shaped radiator. It is printed on an FR-4 dielectric with an overall size of 38 × 45 × 1.6 mm3. Fundamental characteristics of the antenna in terms of return loss, Smith Chart, phase, radiation pattern, and antenna gain are investigated and good results are obtained. Simulations have been carried out using computer simulation technology (CST) software. A prototype of the antenna was fabricated and its characteristics were measured. The measured results show good agreement with simulations. The structure of the antenna is planar, simple to design and fabricate, easy to integrate with RF circuit, and suitable for use in RFID systems.
Risk of Cancer after Lower Urinary Tract Infection: A Population-Based Cohort Study
Authors: Huang Chia-Hung , Chou Ying-Hsiang , Yeh Han-Wei , Huang Jing-Yang , Yang Shun-Fa , Yeh Chao-Bin
Published: January 2019

To investigate the association among lower urinary tract infection (UTI), the type and timing of antibiotic usage, and the subsequent risk of developing cancers, especially genitourinary cancers (GUC), in Taiwan. This retrospective population-based cohort study was conducted using 2009–2013 data from the Longitudinal Health Insurance Database. This study enrolled patients who were diagnosed with a UTI between 2010 and 2012. A 1:2 propensity score-matched control population without UTI served as the control group. Multivariate analysis with a multiple Cox regression model was applied to analyze the data. A total of 38,084 patients with UTI were included in the study group, and 76,168 participants without UTI were included in the control group. The result showed a higher hazard ratio of any cancer in both sexes with UTI (for males, adjusted hazard ratio (aHR) = 1.32; 95% confidence interval (CI) = 1.12–1.54; for females, aHR = 1.21; 95% CI = 1.08–1.35). Patients with UTI had a higher probability of developing new GUC than those without UTI. Moreover, the genital organs, kidney, and urinary bladder of men were significantly more affected than those of women with prior UTI. Furthermore, antibiotic treatment for more than 7 days associated the incidence of bladder cancer in men (7–13 days, aHR = 1.23, 95% CI = 0.50–3.02; >14 days, aHR = 2.73, CI = 1.32–5.64). In conclusion, UTI is significantly related to GUC and may serve as an early sign of GUC, especially in the male genital organs, prostate, kidney, and urinary bladder. During UTI treatment, physicians should cautiously prescribe antibiotics to patients.
On the Kinetics of Degradation Reaction Determined Post Accelerated Weathering of Polyolefin Plastic Waste Blends
Authors: Al-Salem S.M. , Behbehani M.H. , Karam H.J. , Al-Rowaih S.F. , Asiri F.M.
Published: January 2019

Polyolefin (PO) polymers constitute the majority of consumer plastic commodities. The reliance on such materials make it near imposable to avoid touching one in any given day. Therefore, the accumulation of plastic solid waste (PSW) in developed and developing societies alike requires immediate attention to manage and valorize this type of waste. In this work, PSW originating from real life sources and virgin linear low-density polyethylene (LLDPE) films were compounded in a mechanical recycling effort. The recycled blends constituted up to 100% (by weight) of the waste material. Accelerated weathering (aging) was conducted on the blends, reaching threshold limit of exposure to study the major changes occurring on the recycled blends. Thermogravimetry and differential scanning calorimetry (DSC) were used to determine their characteristics and applicability for future recycling using thermo-chemical treatment (TCT) methods. Analytical solution methods following the international committee of thermal analysis and calorimetry (ICTAC) were followed in conducting the measurements and kinetic calculations alike. A novel analytical mathematical solution model is also introduced to determine both the pre-exponential factor (Ao) and apparent activation energy (Ea) of the degradation reaction. The model proved to be a more accurate analysis tool, and the work in whole enabled the determination of future plans for using such waste components as a feedstock to thermal units.
Access or Accessibility? A Critique of the Urban Transport SDG Indicator
Authors: Brussel Mark , Zuidgeest Mark , Pfeffer Karin , van Maarseveen Martin
Published: January 2019

Progress towards the UN Sustainable Development Goals (SDGs) is being evaluated through the use of indicators. Despite the importance of these indicators, the academic community has done little in terms of a critical reflection on their choice, relevance, framing and operationalization. This holds for many SDG domains, also for the urban sector domain of target 11. To partially address this void, we aim to critically review the UN methodology for the urban access indicator, SDG indicator 11.2. In discussing its conceptual framing against the background of paradigm shifts in transportation planning, we argue that this indicator has a number of shortcomings. The most important one is that it is supply oriented and measures access to transportation infrastructure, rather than accessibility to activity locations. As an alternative, we develop two accessibility indicators that show substantial variation in accessibility across geographical areas. We implement all indicators for the city of Bogotá in Colombia, using a geo-information based approach. Our results show that SDG indicator 11.2 fails to represent the transport reality well. Its supply oriented focus neglects transport demand, oversimplifies the transport system and hides existing inequalities. Moreover, it does not provide useful evidence for targeting new interventions. The proposed accessibility indicators provide a more diverse, complete and realistic picture of the performance of the transport system. These indicators also capture the large spatial and socio-economic inequalities and can help to target improvements in urban transportation.
Estimating the Available Sight Distance in the Urban Environment by GIS and Numerical Computing Codes
Authors: Bassani Marco , Grasso Nives , Piras Marco , Catani Lorenzo
Published: January 2019

The available sight distance (ASD) is that part of the roadway ahead which is visible to the driver, and should be of sufficient length to allow a vehicle traveling at the designated speed to stop before reaching a stationary object in its path. It is fundamental in assessing road safety of a project or on an existing road section. Unfortunately, an accurate estimation of the available sight distance is still an issue on existing roads, above all due to the lack of information regarding the as-built condition of the infrastructure. Today, the geomatics field already offers different solutions for collecting 3D information about environments at different scales, integrating multiple sensors, but the main issue regarding existing mobile mapping systems (MMSs) is their high cost. The first part of this research focused on the use of a low-cost MMS as an alternative for obtaining 3D information about infrastructure. The obtained model can be exploited as input data of specific algorithms, both on a GIS platform and in a numerical computing environment to estimate ASD on a typical urban road. The aim of the investigation was to compare the performances of the two approaches used to evaluate the ASD, capturing the complex morphology of the urban environment.
Healthy Brain Aging Modifies Microglial Calcium Signaling In Vivo
Authors: Olmedillas del Moral Maria , Asavapanumas Nithi , Uzcátegui Néstor L. , Garaschuk Olga
Published: January 2019

Brain aging is characterized by a chronic, low-grade inflammatory state, promoting deficits in cognition and the development of age-related neurodegenerative diseases. Malfunction of microglia, the brain-resident immune cells, was suggested to play a critical role in neuroinflammation, but the mechanisms underlying this malfunctional phenotype remain unclear. Specifically, the age-related changes in microglial Ca2+ signaling, known to be linked to its executive functions, are not well understood. Here, using in vivo two-photon imaging, we characterize intracellular Ca2+ signaling and process extension of cortical microglia in young adult (2–4-month-old), middle-aged (9–11-month-old), and old (18–21-month-old) mice. Our data revealed a complex and nonlinear dependency of the properties of intracellular Ca2+ signals on an animal’s age. While the fraction of cells displaying spontaneous Ca2+ transients progressively increased with age, the frequencies and durations of the spontaneous Ca2+ transients followed a bell-shaped relationship, with the most frequent and largest Ca2+ transients seen in middle-aged mice. Moreover, in old mice microglial processes extending toward an ATP source moved faster but in a more disorganized manner, compared to young adult mice. Altogether, these findings identify two distinct phenotypes of aging microglia: a reactive phenotype, abundantly present in middle-aged animals, and a dysfunctional/senescent phenotype ubiquitous in old mice.
The TSPO Ligands 2-Cl-MGV-1, MGV-1, and PK11195 Differentially Suppress the Inflammatory Response of BV-2 Microglial Cell to LPS
Authors: Azrad Maya , Zeineh Nidal , Weizman Abraham , Veenman Leo , Gavish Moshe
Published: January 2019

The 18 kDa Translocator Protein (TSPO) is a marker for microglial activation as its expression is enhanced in activated microglia during neuroinflammation. TSPO ligands can attenuate neuroinflammation and neurotoxicity. In the present study, we examined the efficacy of new TSPO ligands designed by our laboratory, MGV-1 and 2-Cl-MGV-1, in mitigating an in vitro neuroinflammatory process compared to the classic TSPO ligand, PK 11195. We exposed BV-2 microglial cells to lipopolysaccharide (LPS) for 24 h to induce inflammatory response and added the three TSPO ligands: (1) one hour before LPS treatment (pretreatment), (2) simultaneously with LPS (cotreatment), and (3) one hour after LPS exposure (post-treatment). We evaluated the capability of TSPO ligands to reduce the levels of three glial inflammatory markers: cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and nitric oxide (NO). We compared the effects of the two novel ligands to PK 11195. Both 2-Cl-MGV-1 and MGV-1 reduced the levels of glial COX-2, iNOS, and NO in LPS-treated BV-2 cells more efficiently than PK 11195. Notably, even when added after exposure to LPS, all ligands were able to suppress the inflammatory response. Due to their pronounced anti-inflammatory activity, 2-Cl-MGV-1 and MGV-1 may serve as potential therapeutics in neuroinflammatory and neurodegenerative diseases.
Development and Characterization of Bioactive Glass Containing Composite Coatings with Ion Releasing Function for Antibiotic-Free Antibacterial Surgical Sutures
Authors: Ciraldo Francesca E. , Schnepf Kristin , Goldmann Wolfgang H. , Boccaccini Aldo R.
Published: January 2019

Resorbable (Vicryl® Plus) sutures were coated with zinc-doped glass (Zn-BG) and silver-doped ordered mesoporous bioactive glass (Ag-MBG) particles by a dip coating technique. A multilayer approach was used to achieve robust coatings. The first coating was a polymeric layer (e.g., PCL or chitosan) and the second one was a composite made of BG particles in a polymer matrix. The coatings were characterized in terms of morphology by scanning electron microscopy (SEM), in vitro bioactivity, and antibacterial properties. Chitosan/Ag-MBG coatings showed the ability to form hydroxyl-carbonate-apatite on their surfaces after immersion in SBF. An antibacterial effect against Gram (+) and Gram (-) bacteria was confirmed, highlighting the potential application of the coated sutures for antibiotic-free approaches.
Hierarchical Structure of iPP During Injection Molding Process with Fast Mold Temperature Evolution
Authors: Speranza Vito , Liparoti Sara , Pantani Roberto , Titomanlio Giuseppe
Published: January 2019

Mold surface temperature strongly influences the molecular orientation and morphology developed in injection molded samples. In this work, an isotactic polypropylene was injected into a rectangular mold, in which the cavity surface temperature was properly modulated during the process by an electrical heating device. The induced thermo-mechanical histories strongly influenced the morphology developed in the injection molded parts. Polarized optical microscope and atomic force microscope were adopted for morphological investigations. The combination of flow field and cooling rate experienced by the polymer determined the hierarchical structure. Under strong flow fields and high temperatures, a tightly packed structure, called shish-kebab, aligned along the flow direction, was observed. Under weak flow fields, the formation of β-phase, as cylindrites form, was observed. The formation of each morphological structure was analyzed and discussed on the bases of the flow and temperature fields, experienced by the polymer during each stage of the injection molding process.
The Number of Topics Optimization: Clustering Approach
Authors: Krasnov Fedor , Sen Anastasiia
Published: January 2019

Although topic models have been used to build clusters of documents for more than ten years, there is still a problem of choosing the optimal number of topics. The authors analyzed many fundamental studies undertaken on the subject in recent years. The main problem is the lack of a stable metric of the quality of topics obtained during the construction of the topic model. The authors analyzed the internal metrics of the topic model: coherence, contrast, and purity to determine the optimal number of topics and concluded that they are not applicable to solve this problem. The authors analyzed the approach to choosing the optimal number of topics based on the quality of the clusters. For this purpose, the authors considered the behavior of the cluster validation metrics: the Davies Bouldin index, the silhouette coefficient, and the Calinski-Harabaz index. A new method for determining the optimal number of topics proposed in this paper is based on the following principles: (1) Setting up a topic model with additive regularization (ARTM) to separate noise topics; (2) Using dense vector representation (GloVe, FastText, Word2Vec); (3) Using a cosine measure for the distance in cluster metric that works better than Euclidean distance on vectors with large dimensions. The methodology developed by the authors for obtaining the optimal number of topics was tested on the collection of scientific articles from the OnePetro library, selected by specific themes. The experiment showed that the method proposed by the authors allows assessing the optimal number of topics for the topic model built on a small collection of English documents.
A Novel Mutant of rLj-RGD3 (rLj-112) Suppressed the Proliferation and Metastasis of B16 Cells through the EGFR Signaling Pathway
Authors: Zheng Yuan-Yuan , Xiao Rong , Zhang Lu-Xin , Yan Hui-Jie , Wang Ji-Hong , Lv Li
Published: January 2019

Lj-RGD3, which contains three Arg–Gly–Asp (RGD) motifs, was first identified from the buccal glands of Lampetra japonica and has been shown to suppress the tumor progression in the previous studies. Apart from the three RGD motifs, Lj-RGD3 is also characterized by its high content of histidine in its amino acid sequence. In order to clarify whether the histidine-rich characterization of Lj-RGD3 is also associated with its anti-tumor activity, mutants were designed in which the three RGD motifs (Lj-112), or all histidines (Lj-27) or both (Lj-26) were deleted. Furthermore, a mutant (Lj-42) in which all histidines and three RGD motifs were respectively substituted with alanines and three Ala–Gly–Asp (AGD) motifs, as well as a mutant (Lj-41) in which all histidines were substituted with alanines was synthesized to avoid alterations in structure which might further cause changes in the peptides’ functions. After recombination and purification, recombinant Lj-112 (rLj-112), recombinant Lj-27 (rLj-27), recombinant Lj-41 (rLj-41), and recombinant Lj-RGD3 (rLj-RGD3) exhibited anti-proliferative activity in B16 cells, respectively; while recombinant Lj-26 (rLj-26) and recombinant Lj-42 (rLj-42) did not affect the proliferation of B16 cells significantly. In addition, the anti-proliferative activity of rLj-112 in B16 cells was due to apoptosis. Typical apoptosis features were observed, including chromatin condensation, fragmented DNA, and increased levels of cleaved caspase 3/caspase 7/nuclear enzyme poly (ADP-ribose) polymerase (PARP) in B16 cells. Similar to rLj-RGD3, rLj-112 was also capable of suppressing the migration and invasion of B16 cells by disturbing the F-actin arrangement. After labeling with FITC, rLj-112 was found localized in the cytoplasm of B16 cells, which induced the internalization of epidermal growth factor receptor (EGFR), suggesting that rLj-112 might block the EGFR mediated signaling pathway. Actually, the phosphorylation level of EGFR and its downstream signal molecules including Akt, PI3K, p38, and ERK1/2 was reduced in the rLj-112 treated B16 cells. In vivo, rLj-112 also inhibited the growth, weight, and volume of the tumors in B16 xenografted C57BL/6 mice without reducing their body weight, indicating that rLj-112 might be safe and might be used as an effective anti-tumor drug in the near future.
Creation and Evaluation of a Preoperative Education Website for Hip and Knee Replacement Patients—A Pilot Study
Authors: Dayucos Amelia , French Laverne , Kelemen Arpad , Liang Yulan , Sik Lanyi Cecilia
Published: January 2019

Background and Objectives: There is limited research on the question of whether web-based preoperative education can improve surgical patient outcomes. The purpose of this pilot study was to determine the usability, utility, and feasibility of a website created to increase engagement and improve the quality of the preoperative education that patients having hip and knee arthroplasty surgery receive. Materials and Methods: A website was created, and its appearance was designed with evidence-based “menu-driven” drop-downs to make the screen options age-appropriate to the patient population; the content was supported with video and PDFs of educational material, the same or similar to the usual education provided to patients. The patient-specific outcomes included qualitative data regarding patient knowledge, satisfaction, utilities, and usability. These objectives were assessed based on the perceived health website usability questionnaire online survey. Eighty patients who met inclusion criteria were recruited, ranging in age from 40 to 65 years old. Among them, 52.5% were female, 71.25% were scheduled for knee arthroplasty, and 28.75% hip arthroplasty. The patients were randomly assigned to the paper only or website education cohorts in a 50:50 ratio. However, only 19 from each cohort participated in the survey questionnaire. Results and Conclusions: We hypothesized that findings would show that patients receiving web-based education would feel more knowledgeable about their procedure, have less anxiety, and greater satisfaction with the addition of the website content; and that nurses would report that a website could conserve nursing time and resources. The study revealed no statistically significant differences between the cohorts, with an Alpha level set at 0.05. However, survey results showed that patients using the website rated self-perceived increase in knowledge, and their satisfaction in the time to find and review the information was higher than that of the paper-only cohort. The nursing survey revealed that website education improved workflow, efficiency, and patient education.
Compressive Properties of A2024 Alloy Foam Fabricated through a Melt Route and a Semi-Solid Route
Authors: Kuwahara Takashi , Osaka Taro , Saito Mizuki , Suzuki Shinsuke
Published: January 2019

A2024 alloy foams were fabricated by two methods. In the first method, the melt was thickened by Mg, which acts as an alloying element (melt route). In the second method, the melt was thickened by using primary crystals at a semi-solid temperature with a solid fraction of 20% (semi-solid route). A2024 alloy foams fabricated through the semi-solid route had coarse and uneven pores. This led to slightly brittle fracture of the foams, which resulted in larger energy absorption efficiency than that of the foams fabricated through the melt route. Moreover, A2024 alloy foams fabricated through the semi-solid route had a coarser grain size because of the coarse primary crystals. However, by preventing the decrease in the alloying element Mg, the θ/θ’ phase was suppressed. Additionally, by preventing the precipitation of the S′ phase, the amount of Guinier-Preston-Bagaryatsky (GPB) zone increased. This resulted in a larger plateau stress.
Candida glabrata: A Lot More Than Meets the Eye
Authors: Kumar Kundan , Askari Fizza , Sahu Mahima Sagar , Kaur Rupinder
Published: January 2019

Candida glabrata is an opportunistic human fungal pathogen that causes superficial mucosal and life-threatening bloodstream infections in individuals with a compromised immune system. Evolutionarily, it is closer to the non-pathogenic yeast Saccharomyces cerevisiae than to the most prevalent Candida bloodstream pathogen, C. albicans. C. glabrata is a haploid budding yeast that predominantly reproduces clonally. In this review, we summarize interactions of C. glabrata with the host immune, epithelial and endothelial cells, and the ingenious strategies it deploys to acquire iron and phosphate from the external environment. We outline various attributes including cell surface-associated adhesins and aspartyl proteases, biofilm formation and stress response mechanisms, that contribute to the virulence of C. glabrata. We further discuss how, C. glabrata, despite lacking morphological switching and secreted proteolytic activity, is able to disarm macrophage, dampen the host inflammatory immune response and replicate intracellularly.
CALB Immobilized onto Magnetic Nanoparticles for Efficient Kinetic Resolution of Racemic Secondary Alcohols: Long-Term Stability and Reusability
Authors: Xing Xiu , Jia Jun-Qi , Zhang Jing-Fan , Zhou Zi-Wen , Li Jun , Wang Na , Yu Xiao-Qi
Published: January 2019

In this study, an immobilization strategy for magnetic cross-linking enzyme aggregates of lipase B from Candida antarctica (CALB) was developed and investigated. Magnetic particles were prepared by conventional co-precipitation. The magnetic nanoparticles were modified with 3-aminopropyltriethoxysilane (APTES) to obtain surface amino-functionalized magnetic nanoparticles (APTES–Fe3O4) as immobilization materials. Glutaraldehyde was used as a crosslinker to covalently bind CALB to APTES–Fe3O4. The optimal conditions of immobilization of lipase and resolution of racemic 1-phenylethanol were investigated. Under optimal conditions, esters could be obtained with conversion of 50%, enantiomeric excess of product (eep) > 99%, enantiomeric excess of substrate (ees) > 99%, and enantiomeric ratio (E) > 1000. The magnetic CALB CLEAs were successfully used for enzymatic kinetic resolution of fifteen secondary alcohols. Compared with Novozym 435, the magnetic CALB CLEAs exhibited a better enantioselectivity for most substrates. The conversion was still greater than 49% after the magnetic CALB CLEAs had been reused 10 times in a 48 h reaction cycle; both ees and eep were close to 99%. Furthermore, there was little decrease in catalytic activity and enantioselectivity after being stored at −20 °C for 90 days.
T1-Weight Magnetic Resonance Imaging Performances of Iron Oxide Nanoparticles Modified with a Natural Protein Macromolecule and an Artificial Macromolecule
Authors: Tao Cheng , Zheng Qiang , An Lu , He Meie , Lin Jiaomin , Tian Qiwei , Yang Shiping
Published: January 2019

To optimize the iron oxide nanoparticles as T1-weight contrast for in vivo magnetic resonance imaging (MRI), numbers of macromolecule ligands have been explored with considerable effort. However, reports refer to the comparison of the T1-weight contrast performances of iron oxide nanoparticles modified with natural and artificial macromolecule ligands are still limited. In this work, we used a typical natural protein macromolecule (bovine serum albumin, BSA) and an artificial macromolecule (poly(acrylic acid)-poly(methacrylic acid), PMAA-PTTM) as surface ligands to fabricate Fe3O4-BSA and Fe3O4-PMAA-PTTM nanoparticles with similar size and magnetization by the coprecipitation method and compared their MRI performances. In vitro and in vivo experiments revealed that Fe3O4-BSA with lower cytotoxicity exhibited higher r2/r1 ratio in solution and darkening contrast enhancement for liver and kidney sites of mice under T1-weight imaging, while Fe3O4-PMAA-PTTM displayed much lower r2/r1 ratio in solution and brighter contrast enhancement for liver and kidney sites. These remarkably different MRI behaviors demonstrated that the surface ligands play an important role for optimizing the MRI performance of Fe3O4 nanoparticles. We expect these results may facilitate the design of macromolecule ligands for developing an iron oxide–based T1-weight contrast agent.
A Bio-Compatible Fiber Optic pH Sensor Based on a Thin Core Interferometric Technique
Authors: Engholm Magnus , Hammarling Krister , Andersson Henrik , Sandberg Mats , Nilsson Hans-Erik
Published: January 2019

There is an increasing demand for compact, reliable and versatile sensor concepts for pH-level monitoring within several industrial, chemical as well as bio-medical applications. Many pH sensors concepts have been proposed, however, there is still a need for improved sensor solutions with respect to reliability, durability and miniaturization but also for multiparameter sensing. Here we present a conceptual verification, which includes theoretical simulations as well as experimental evaluation of a fiber optic pH-sensor based on a bio-compatible pH sensitive material not previously used in this context. The fiber optic sensor is based on a Mach-Zehnder interferometric technique, where the pH sensitive material is coated on a short, typically 20-25 mm thin core fiber spliced between two standard single mode fibers. The working principle of the sensor is simulated by using COMSOL Multiphysics. The simulations are used as a guideline for the construction of the sensors that have been experimentally evaluated in different liquids with pH ranging from 1.95 to 11.89. The results are promising, showing the potential for the development of bio-compatible fiber optic pH sensor with short response time, high sensitivity and broad measurement range. The developed sensor concept can find future use in many medical- or bio-chemical applications as well as in environmental monitoring of large areas. Challenges encountered during the sensor development due to variation in the design parameters are discussed.
Advances in Mathematical Modeling of Gas-Phase Olefin Polymerization
Authors: Atan Mohd Farid , Hussain Mohd Azlan , Abbasi Mohammad Reza , Khan Mohammad Jakir Hossain , Fazly Abdul Patah Muhamad
Published: January 2019

Mathematical modeling of olefin polymerization processes has advanced significantly, driven by factors such as the need for higher-quality end products and more environmentally-friendly processes. The modeling studies have had a wide scope, from reactant and catalyst characterization and polymer synthesis to model validation with plant data. This article reviews mathematical models developed for olefin polymerization processes. Coordination and free-radical mechanisms occurring in different types of reactors, such as fluidized bed reactor (FBR), horizontal-stirred-bed reactor (HSBR), vertical-stirred-bed reactor (VSBR), and tubular reactor are reviewed. A guideline for the development of mathematical models of gas-phase olefin polymerization processes is presented.
Measuring Canopy Structure and Condition Using Multi-Spectral UAS Imagery in a Horticultural Environment
Authors: Tu Yu-Hsuan , Johansen Kasper , Phinn Stuart , Robson Andrew
Published: January 2019

Tree condition, pruning and orchard management practices within intensive horticultural tree crop systems can be determined via measurements of tree structure. Multi-spectral imagery acquired from an unmanned aerial system (UAS) has been demonstrated as an accurate and efficient platform for measuring various tree structural attributes, but research in complex horticultural environments has been limited. This research established a methodology for accurately estimating tree crown height, extent, plant projective cover (PPC) and condition of avocado tree crops, from a UAS platform. Individual tree crowns were delineated using object-based image analysis. In comparison to field measured canopy heights, an image-derived canopy height model provided a coefficient of determination (R2) of 0.65 and relative root mean squared error of 6%. Tree crown length perpendicular to the hedgerow was accurately mapped. PPC was measured using spectral and textural image information and produced an R2 value of 0.62 against field data. A random forest classifier was applied to assign tree condition into four categories in accordance with industry standards, producing out-of-bag accuracies >96%. Our results demonstrate the potential of UAS-based mapping for the provision of information to support the horticulture industry and facilitate orchard-based assessment and management.