bluuebunny/crossref_metadata_2025 huggingface dataset:
Water quality status of an urban lake in the dry season from 2017 to 2020 (Situ Gintung, Banten Province, Indonesia)
Authors: Ramadhania Putri Maresi Sinta , Edhi Budhi Soesilo Tri , Aminah Meutia Ami
Published: November 2020

Urban lakes are experiencing various kinds of problems because of the anthropocentrism of environmental management. This also happens in Situ Gintung, Indonesia. This lake is polluted by many pollutants from urban activities, such as the entry of domestic waste into waters due to anthropogenic activities and the amount of leftover food not consumed by fisheries. These problems can be solved by observing the water quality of Situ Gintung to provide information about parameters that have exceeded environmental quality standards and provide general information about the water quality in the dry season from 2017 to 2020. The research is done using a purposive sampling method and determining water quality status with the STORET method based on the Indonesian standard with parameters less than ten. As a result, Situ Gintung water is neither classified as class I, II, III, and IV nor be utilized for consumption, recreation, fisheries, and irrigation because the quality status is mostly in the heavily polluted category. Furthermore, the three highest polluters from each class are BOD5, COD, and a total of Coliform.
Study of carbon dioxide electrochemical reduction in flow cell system using copper modified boron-doped diamond
Authors: Zahran Ilyasa Salsabila , Krisma Jiwanti Prastika , Khalil Munawar , Einaga Yasuaki , Anggraningrum Ivandini Tribidasari
Published: November 2020

High concentrations of CO2 in the atmosphere may cause climate and environmental changes. Therefore, various research has been extensively performed to reduce CO2 by converting CO2 directly into hydrocarbons. In this research, CO2 electrochemical reduction was studied using boron-doped diamond (BDD) modified with copper nanoparticles to improve BDD electrodes’ catalytic properties. The deposition was performed by chronoamperometry technique at a potential of -0.6 V (vs. Ag/AgCl) and characterized using SEM, EDS, XPS, and cyclic voltammetry (CV). CO2 electrochemical reduction on BDD and Cu-BDD was carried out at -1.5 V (vs. Ag/AgCl) for 60 minutes. The products were analyzed using HPLC and GC. The product was mainly formic acid with a concentration of 11.33 mg/L and 33% faradaic efficiency on a Cu-BDD electrode.
Optimization of solid waste collection circuits
Authors: Haddoun Nezha , Khomsi Driss
Published: November 2020

The management of solid waste is a significant problem that can negatively affect human health, the environment, and the living environment. One of the biggest threats to sustainable development is environmental pollution due to poor waste management. The ‘’collection’’ component represents the most expensive link in management and is subject to several constraints. Its optimization will, therefore, make it possible to optimize the overall cost of management. Solving the problem comes down to solving the “Periodic Capacitated Arc Routing Problem” PCARP, an extension of the famous CARP problem over several periods. The objective is to minimize the number of vehicles required and the total cost of collection trips according to the set schedule. This document defines this NP-difficult problem, summarizes the different optimization methods used to solve the problem with a literature review, and discusses the latest studies and results.
Community engagement and waste management policy: A comparative analysis
Authors: Brotosusilo Agus , Hilya Nabila Siti
Published: November 2020

Municipal waste management has become a significant problem in many urban areas where solutions are complex and conflicting to form. One of the most important actors that can control waste management in a country is the government. Then the most important tool for setting standards in maintaining waste management is the public policy. Therefore, this paper will review and evaluate public policies that regulate solid waste management in China, Japan, and Malaysia, using secondary data. The three countries were chosen because their cases represented various significant and different factors that have often been an obstacle to waste management. The three case studies discuss community behavior analysis, policy mistranslation, and the lack of waste management infrastructure. The main obstacles of the waste management policy are to control people’s behavior, lack of garbage infrastructure, waste pickers are not organized, and lack of progress in waste management and recycling technology. The waste management policy needs to focus on increasing residents’ awareness to recycle and expand the producer’s responsibility to increase community engagement and boost successful waste management in a region or country.
Spatial dynamics of agricultural land in Banyuasin Regency, South Sumatera: Its opportunities and threats
Authors: Pujawati Intan , Suryanegara Ellen , Munawaroh  , Rudiastuti Aninda W.
Published: November 2020

The availability of agricultural land, especially paddy fields, is an inseparable part of efforts to maintain national food security and engage SDGs’ second goal. Changes in land cover/land use can occur due to social, political, economic, cultural, natural, and technological factors. Geographic Information Systems (GIS) operate as a tool to comprehend the changes related to the driver’s factors. The purpose of this study was to examine the spatial dynamics of paddy land cover in the Banyuasin Regency for more than 2 decades using the Markov Chain approach and to analyze the inhibiting and supporting factors in developing paddy farming in the region. The inhibiting factor discussed in this study is the potentiality of floods in paddy fields. The results showed that paddy fields in Banyuasin Regency experienced the widest decrease of 2,863.80 hectares and encountered the largest increase of 14,463.45 hectares in 1990-2003. The threat factor also influenced changes in the area of agricultural land in the form of inundation. The flood inundation crisis peaked in 2010, where 832.58 hectares out of 164,562.37 hectares of paddy field were flooded. However, the potency in developing lowland rice farming on swamps in Banyuasin Regency is considerably beneficial. This can be examined from the value of Revenue-Cost Ratio (R/C Ratio), averaging 3.65, and BenefitCost Ratio (B/C Ratio) of 2.65 with an average production of 5-7 tons/hectares/season.
Quito’s coronavirus curfew: Escalating tropospheric ozone pollution
Authors: Salazar Cristian , Kurbatova Anna I. , Kupriyanova Milana E.
Published: November 2020

The effect of the curfew due to the pandemic of Covid-19 virus on the levels of air pollution in the historic center of Quito was evaluated with a focus on tropospheric ozone (O3). During the curfew period the daily O3 mean concentration increased by 96%, 109% and 95% in comparison to the concentrations for the same period in the years 2017, 2018 and 2019. This increase is mainly explained by considerable reduction in NOx emissions, thus there was little titration of ozone accumulated in the city environment due to its shallow boundary layer by NO, reaching its maximum concentration at midday. Among studied pollutants that influence O3 formation (CO, NO2, PM2.5) during the curfew the contaminant that showed the greatest reduction in the mean concentration compared to three previous years was NO2, followed by CO and PM2.5. The daily O3 8-hour mean concentrations during the curfew both on weekdays and weekends were lower than the limit values. These results are relevant for designing abatement policies of secondary pollutants such as O3 under strict measures of control of primary pollutant emissions.
Pembelajaran jarak jauh during covid 19 pandemic in Indonesia and development sustainable
Authors: Iswary Lawanda Ike
Published: November 2020

Distance learning (Pembelajaran Jarak Jauh) during pandemic Covid-19 in Indonesia indicating the image of the ideal is a way to culturally resilient adaptation. Students from primary school until higher education includes adults and institutions identify problems on infrastructure and behavior that show conscience as cultural resilience. The methodology of constructivism using method of interpretation of documentation and interview become data for the research paper. Informants of three students, parents and a teacher of music class Matahari primary school selected whom having the experience of distance learning are to interpret conscience. The distance learning to students appeals to have impacts on every individual related such as parents and revitalize their conscience in order to and for resilience following resistance and accommodation. Most people try to behave using their ability to navigate during this period of hardship on psychological, social, cultural and physical resources. They negotiate resources in a meaningful way to the advantage of person or group. In conclusion, conscience becomes cultural resilience triggered by pembelajaran jarak jauh during pandemic of Covid-19 in Indonesia. Human consciousness upon conscience appear to sustain culturally after experiencing exaggerated and overwhelming feeling of being lockdown and sense being in cage beside problems in shifting behavior.
Mapping data on Indonesia’s worst forest and land fires of palm oil cultivation lands
Authors: Frimawaty Evi
Published: November 2020

During the last semester of 2019, Indonesia was hit by major forest and land fires in Sumatera and Kalimantan. The culprit of a large number of smokes were palm oil cultivation lands. This study uses data collected from Aqua and Terra satellite of Nasa to visualize the hotspots’ severity, causing some provinces to become smoky. The severe hotspots were located on Riau, West Kalimantan, and Central Kalimantan through visualization density. The hotspots detected in this study vary from 300 to 468 degrees Fahrenheit, shown by the brightness of visualized colors on the map. This study also found that the forest and land forest fires have reached its peak during August 2019.
Estimation and potential of palm oil empty fruit bunches based on crude palm oil forecasting in Indonesia
Authors: Dwi Januari Arty , Warno Utomo Suyud , Agustina Haruki
Published: November 2020

The increase of palm oil production produced waste, which has an impact on the environmental burden. Therefore, the purpose of this article is to predict the amount of palm oil empty fruit bunches produced per month in Indonesia to determine the potential of empty fruit bunches management. The predicted amount of the waste is based on crude palm oil (CPO) forecasts analysis that is processed using exponential triple smoothing. Based on the analysis, it was obtained that the amount of waste of empty fruit bunches proved to be directly proportional to the crude palm oil production. The efficiency of mill operation plays an essential role in CPO production and waste generation. However, this study has less variance on empty fruit bunches production since that quantity derived directly from CPO forecasting results based on fresh fruit bunches processed in the mills. Based on the estimation quantity, the management of palm oil empty fruit bunch as a raw material of fertilizer is sufficient to manage the produced empty fruit bunch. The data can be used to consider the waste palm’s potential management in palm oil mills and national scope.
Challenging Atroposelective C–H Arylation
Authors: Wencel-Delord Joanna , Colobert Françoise
Published: November 2020

Atropisomeric molecules are privileged scaffolds, not only as ligands for asymmetric synthesis, but also as biologically active products and advanced materials. Although very attractive from a sustainability viewpoint, the direct construction of the stereogenic axis through asymmetric C–H arylation is very challenging and consequently only a few examples have been reported. This short review summarizes these very recent results on the atropo-enantio or diastereo­selective synthesis of atropisomeric (hetero)biaryl molecules; transformations during which the Ar–Ar atropisomeric axis is formed during the C–H activation process.

1 Introduction

2 Atropo-enantioselective Intermolecular Pd-Catalyzed C–H Arylation of Thiophene Derivatives

3 Atropodiastereoselective Intermolecular Pd-Catalyzed C–H Arylation towards Terphenyl Scaffolds Bearing Two Atropisomeric Axes

4 Atropo-enantioselective Intramolecular Pd-Catalyzed C–H Arylation towards Atropisomeric Benzodiazepinones

5 Atropo-enantioselective Intermolecular Pd-Catalyzed C–H Arylation of Heteroarenes

6 Rh-Catalyzed Atropo-enantioselective C–H Arylation of Diazonaphthoquinones

7 Conclusion
Rate coefficients and kinetic isotope effects of Cl+XCl→XCl+Cl (X=H,
D, Mu) reactions from ring polymer molecular dynamics
Authors: Fang Jun-hua , Fan Wen-bin , Yang Hui , Song Jia-ning , Li Yong-le
Published: November 2020

The ring-polymer molecular dynamics (RPMD) was used to calculate the thermal rate coefficients and kinetic isotope effects of the heavy-light-heavy abstract reaction Cl+XCl→XCl+Cl (X=H, D, Mu). For the Cl+HCl reaction, the excellent agreement between the RPMD and experimental values provides a strong proof for the accuracy of the RPMD theory. And the RPMD results are also consistent with results from other theoretical methods including improved-canonical-variational-theory and quantum dynamics. The most novel finding is that there is a double peak in Cl+MuCl reaction near the transition state, leaving a free energy well. It comes from the mode softening of the reaction system at the peak of the potential energy surface. Such an explicit free energy well suggests strongly there is an observable resonance. And for the Cl+DCl reaction, the RPMD rate coefficient again gives very accurate results compared with experimental values. The only exception is at the temperature of 312.5 K, results from RPMD and all other theoretical methods are close to each other but slightly lower than the experimental value, which indicates experimental or potential energy surface deficiency.
Study of the structure of exploding flat foils at superhigh current density
Authors: Shelkovenko T. A. , Pikuz S. A. , Tilikin I. N. , Mingaleev A. R. , Romanova V. M. , Hammer D. A.
Published: November 2020

We have investigated the features produced in flat metal foils as a result of nanosecond explosions and phase transitions at current densities of (0.1–2) ⋅ 109 A/cm2. Thin foils made of aluminum, copper, nickel, and titanium, with thicknesses of 1–15 μm, were tested. The exploded foil structure was studied using X-pinch radiography and laser shadow imaging. Al, Ti, and Cu (5 and 7 μm thick) foils had an initial two-dimensional structure. At the same time, no apparent structure was registered in 1 μm Cu and 5 μm Ni foils. Experiments on generators with different output parameters have shown that the dominant structures that developed in the explosion are either cracks or bubbles and may depend on the orientation of the initial structure in the thin foil with respect to the current direction. In addition, the energy deposited in the foil differs by a factor of about 1.5 for the orthogonal vs parallel current and initial foil structure directions.
Effect of plasma hydrodynamics on laser-produced bremsstrahlung MeV photon dose
Authors: Courtois C. , Compant La Fontaine A. , Bonnet T. , Gobet F. , Hannachi F. , Marquès J. R. , Tarisien M. , Versteegen M. , Vinci T.
Published: November 2020

We detail a laser plasma experiment aimed at enhancing laser to MeV electron energy coupling and then the x-ray dose produced when a short pulse laser propagates through a long preformed plasma. This study can be of interest not only for radiography of high areal mass objects requiring large doses but also for radiation safety of large scale laser facilities such as LMJ or NIF able to produce long preformed plasmas through which a short pulse laser can propagate. A low-intensity (∼1014 W/cm2) ns beam explodes a thin foil deposited on a high-Z solid target to generate an underdense plasma. An intense (>1018 W/cm2) and short (<1 ps) laser pulse then (with an adjustable delay δt) interacts with this plasma and produces multi-MeV electrons. These high-energy electrons are converted into a bremsstrahlung emission of MeV x-ray photons in the high-Z target. In a second target design, a vacuum gap between the foil and the conversion target is also tested to let the plasma expand on both sides of the foil, increasing the interaction length even more. Results show how the vaporization of the foil produces an underdense plasma over several hundreds of micrometers which significantly enhances x-ray doses, with harder x-ray spectra obtained at an optimum delay, δt, until the short pulse laser is affected by refraction. Increasing the interaction length with gap targets is at the origin of a much more complex plasma hydrodynamics involving on-axis plasma stagnation which delays the optimum time for the maximum x-ray dose production.
Investigation of magnetic ordering and origin of exchange-bias effect in doped manganite, Sm0.4Ca0.6MnO3
Authors: Kumar Amit , Giri S. K. , Nath T. K. , Ritter C. , Yusuf S. M.
Published: November 2020

We have carried out detailed investigations of magnetic ordering and the origin of exchange-bias phenomenology in polycrystalline 154Sm0.4Ca0.6MnO3 perovskite compound by employing dc and ac magnetizations, neutron depolarization, and neutron diffraction techniques. The neutron diffraction study reveals a broad charge ordering transition in the temperature range of 275–150 K, manifested by gradually varying structural distortions. DC magnetization and neutron diffraction studies infer a magnetic ordering around 110 K. Below ∼40 K, this compound exhibits a large enhancement of the magnetization and an exchange-bias effect (∼18 kOe at 5 K). The exchange-bias effect shows a characteristic temperature and cooling field dependence and a training effect. The compound undergoes a CE-type (checker-board type) antiferromagnetic (AFM) ordering of Mn3+/Mn4+ spins below 110 K. The large magnetization below ∼40 K arises from the ferrimagnetic (FIM) ordering of a minority (∼5 vol. %) non-perovskite phase of Mn3O4. The appearance of exchange bias is ascribed due to the presence of an interface, formed between the FIM (Mn3O4) phase and the main AFM perovskite phase. Our study has implications in giving new directions in the search of large exchange-bias effects in mixed FIM/AFM bulk systems.
Fast Fourier transform and multi-Gaussian fitting of XRR data to determine the thickness of ALD grown thin films within the initial growth regime
Authors: Lammel Michaela , Geishendorf Kevin , Choffel Marisa A. , Hamann Danielle M. , Johnson David C. , Nielsch Kornelius , Thomas Andy
Published: November 2020

While a linear growth behavior is one of the fingerprints of textbook atomic layer deposition processes, the growth often deviates from that behavior in the initial regime, i.e., the first few cycles of a process. To properly understand the growth behavior in the initial regime is particularly important for applications that rely on the exact thickness of very thin films. The determination of the thicknesses of the initial regime, however, often requires special equipment and techniques that are not always available. We propose a thickness determination method that is based on X-ray reflectivity (XRR) measurements on double layer structures, i.e., substrate/base layer/top layer. XRR is a standard thin film characterization method. Utilizing the inherent properties of fast Fourier transformation in combination with a multi-Gaussian fitting routine permits the determination of thicknesses down to t≈2 nm. We evaluate the boundaries of our model, which are given by the separation and full width at half maximum of the individual Gaussians. Finally, we compare our results with data from x-ray fluorescence spectroscopy, which is a standard method for measuring ultra-thin films.
Tunable acoustics with dielectric elastomer activated granular jamming exhibiting a solid–fluid transition
Authors: Wissman James , Ikei Alec , Konarski Stephanie G. , Rohde Charles A. , Naify Christina J.
Published: November 2020

Acoustic metamaterials, which manipulate acoustic propagation using architected, discrete structures, have wide ranges of applications but typically have a fixed response upon design and fabrication. We present a novel tunable acoustic structure with a granular jamming-based approach, where the jammed state acts as a solid with a well defined resonant response and the unjammed state acts as a liquid with a broad, weakly resonant response. In between these two extremes, resonance peak tuning is observed. Our approach to particle jamming is uniquely controlled with a dielectric elastomer actuator (DEA), whose applied confining pressure is governed by voltage. Mathematical modeling of the DEA and the confining pressure is used to understand the device behavior. Samples are fabricated and tested acoustically, revealing a novel solid–liquid like transition at an applied voltage of about 6.0 kV and a preceding “rattler” behavior at around 4.25 kV.
Seasonal occupancy of abandoned mines by cave-dwelling bats in the western Blue Mountains, New South Wales
Authors: Williams Elizabeth R.
Published: November 2020

Cave-dwelling microbats are known to occupy abandoned mines, which can be important habitat for threatened species. Surveys and monitoring between 2012 and 2014 in Mugii Murum-ban State Conservation Area identified use of three adits from historic mine workings by three species: Chalinolobus dwyeri, Miniopterus orianae oceanensis and Rhinolophus megaphyllus. One of the adits is a potential small maternity roost for the threatened M. o. oceanensis, as indicated by captures of pregnant females in December 2014, as well as increased emergence counts and call activity in spring compared with autumn. While there were some signs of reproducing R. megaphyllus at the adits (a single pregnant female in late October, and postlactating females and juveniles in February) the complete absence of females during December trapping indicated otherwise. Use of the three adits was typical for roost and access preferences of the species, with only R. megaphyllus occupying a doored adit and all species recorded at a large unobstructed adit, and a shallow adit likely only used as a night roost by all species.
A cultural linguistic analysis of Swahili body metaphors
Authors: Tramutoli Rosanna
Published: November 2020

This study describes the relationship between language, culture and conceptualization, considering in particular the
embodied cultural metaphors of ‘heart’ and ‘liver’. The recent study by Kraska-Szlenk (2014) on
the semantic analysis of Swahili body terminology has demonstrated that moyo (heart) has a prominent role in the
conceptualization of numerous emotional states, with several different metaphorical meanings (e.g., love, generosity, will). However, from a
diachronic perspective, ini (liver) is equally important for the metaphorical expression of emotions or character traits in
Swahili. Considering in addition the practice of Swahili traditional medicine (uganga), this study highlights Swahili
bodily conceptualizations involved in the expression of emotions and personal traits. The data were collected mostly through interviews with
Swahili speakers during fieldwork conducted in Tanzania.
Effects of task type on L2 Mandarin fluency development
Authors: Wright Clare
Published: November 2020

This study explores task effects on fluency development in second language (L2) Mandarin during study abroad (SA) in China, given linguistic and pedagogic challenges facing western learners of Mandarin (Zhao, 2011). Data from 10 adult English learners of Mandarin were compared pre/post 10 months’ SA in China. Performance was measured in 4 tasks with different task loads (rehearsed vs. spontaneous speech, in monologic and dialogic mode). Significant differences between the rehearsed monologue and other tasks found pre-SA were generally not found after SA. Some differences remained between monologues and dialogues, suggesting that task load effects may override SA impact. Claims about the impact of SA on L2 oral development should take more account of different task demands, to help further illuminate our understanding of how SA may benefit L2 fluency.
Inherited SLP76 deficiency in humans causes severe combined immunodeficiency, neutrophil and platelet defects
Authors: Lev Atar , Lee Yu Nee , Sun Guangping , Hallumi Enas , Simon Amos J. , Zrihen Keren S. , Levy Shiran , Beit Halevi Tal , Papazian Maria , Shwartz Neta , Somekh Ido , Levy-Mendelovich Sarina , Wolach Baruch , Gavrieli Ronit , Vernitsky Helly , Barel Ortal , Javasky Elisheva , Stauber Tali , Ma Chi A. , Zhang Yuan , Amariglio Ninette , Rechavi Gideon , Hendel Ayal , Yablonski Deborah , Milner Joshua D. , Somech Raz
Published: November 2020

The T cell receptor (TCR) signaling pathway is an ensemble of numerous proteins that are crucial for an adequate immune response. Disruption of any protein involved in this pathway leads to severe immunodeficiency and unfavorable clinical outcomes. Here, we describe an infant with severe immunodeficiency who was found to have novel biallelic mutations in SLP76. SLP76 is a key protein involved in TCR signaling and in other hematopoietic pathways. Previous studies of this protein were performed using Jurkat-derived human leukemic T cell lines and SLP76-deficient mice. Our current study links this gene, for the first time, to a human immunodeficiency characterized by early-onset life-threatening infections, combined T and B cell immunodeficiency, severe neutrophil defects, and impaired platelet aggregation. Hereby, we characterized aspects of the patient's immune phenotype, modeled them with an SLP76-deficient Jurkat-derived T cell line, and rescued some consequences using ectopic expression of wild-type SLP76. Understanding human diseases due to SLP76 deficiency is helpful in explaining the mixed T cell and neutrophil defects, providing a guide for exploring human SLP76 biology.
Compromised counterselection by FAS creates an aggressive subtype of germinal center lymphoma
Authors: Razzaghi Raud , Agarwal Shreya , Kotlov Nikita , Plotnikova Olga , Nomie Krystle , Huang Da Wei , Wright George W. , Smith Grace A. , Li Moyi , Takata Katsuyoshi , Yamadi Maryam , Yao Chen , O’Shea John J. , Phelan James D. , Pittaluga Stefania , Scott David W. , Muppidi Jagan R.
Published: November 2020

Fas is highly expressed on germinal center (GC) B cells, and mutations of FAS have been reported in diffuse large B cell lymphoma (DLBCL). Although GC-derived DLBCL has better overall outcomes than other DLBCL types, some cases are refractory, and the molecular basis for this is often unknown. We show that Fas is a strong cell-intrinsic regulator of GC B cells that promotes cell death in the light zone, likely via T follicular helper (Tfh) cell–derived Fas ligand. In the absence of Fas, GCs were more clonally diverse due to an accumulation of cells that did not demonstrably bind antigen. FAS alterations occurred most commonly in GC-derived DLBCL, were associated with inferior outcomes and an enrichment of Tfh cells, and co-occurred with deficiency in HVEM and PD-L1 that regulate the Tfh–B cell interaction. This work shows that Fas is critically required for GC homeostasis and suggests that loss of Tfh-mediated counterselection in the GC contributes to lethality in GC-derived lymphoma.
Fundamental mode intensity evolution in tapered optical fibres
Authors: Ek-Ek J R , Martinez-Pinon F , Alvarez-Chavez J A , Ceballos-Herrera D E , Sanchez-Lara R , Offerhaus H L
Published: November 2020

The mode field intensity, spot size, central peak intensity evolution and adiabaticity are calculated for different points along the transition of an optical fibre taper that adiabatically tapers from the standard 125 nm down to 1 µm and then to 440 nm diameter for low loss operation at 1550 nm wavelength. The first section of the taper is evaluated using a weak guidance approximation. The second section is treated as a three-index layer structure (double-clad) and evaluated with eigenvalue equations for three refractive indices. The third and thinnest section of the taper is studied using an exact mode eigenvalue equation. The results show that the fundamental mode for the third section has a discontinuity at the fibre edge with a peak intensity larger than the intensity at the centre of the fibre. Since the guiding by the core disappears in the first section of the taper, the mode field does not simply reduce monotonously along the taper with the outer diameter of the fibre. By this novel approach, and for the first time, to the best of our knowledge, the taper shape that complies with the adiabaticity criterion, the mode intensity profile and the spot size (first Petermann definition) of the fundamental mode evolution, along their position on the taper are determined.
Effect of DNA on the optical properties of ZnO:SiO2:La3+
films
Authors: Hayrullina I A , Nagovitsyn I A , Boruleva E A , Lobanov A V , Chudinova G K
Published: November 2020

ZnO–SiO2 composite films doped with La3+ ions (0.1%–5.0% mass.) were obtained using the sol–gel method. The absorption and ultraviolet luminescence spectra of the films, as well as the change in spectral characteristics under the influence of DNA, were studied. Doping of ZnO:SiO2 films with La3+ ions leads to an increase in the transmittance in the UV range (λ = 357 nm) from 4.5% (for undoped films) to 32%–34%, and the transmittance is inversely proportional to the amount of dopant. In all doped films, the optical band gap increases in comparison with undoped films (3.35 eV) and amounts to 3.830–3.853 eV. The application of DNA to the surface weakly affects the value of optical band gap. The maximum of the ultraviolet luminescence (UVL) band in ZnO:SiO2:La3+ films is slightly shifted depending on the amount of dopant and is located at λem = 363–367 nm. An increase in UVL intensity was observed upon doping by a factor of 8.4–9.6 compared to ZnO:SiO2 films. A change in the amount of dopant does not lead to sharp changes in the magnitude of the intensity. Thus, the UVL intensity (λex = 260), compared with films with 0.1% La3+ content, varies by 5%–11%. The effect of small amounts of DNA was studied for films doped with La3+. In the case of ZnO:SiO2:La3+, both extinguishing (up to 12%) and ignition (up to 5%) of UVL were observed. Monotone dependencies (which are desirable for the biosensor sensing element) were obtained for samples with La3+ 0.1 and 1.0% content. SEM images show that the images for zinc oxide are white crystallites of different sizes: from 0.5 µm to conglomerates of crystallites −1 µm. In the presence of DNA, the surface structure changes due to the formation of rhomboid structures, whose sizes vary from 3 µm to 35 µm. It is known that lanthanum ions induce the compaction of DNA with the formation of nanoscale structures.
Effect of Dynamic Vulcanization on Properties of Linear Low Density Polyethylene/Natural Rubber Filled with Calcium Carbonate
Authors: Annie Loh , Wahab Mohamad Kahar Ab , Jayamani Elammaran
Published: November 2020

The effect of dynamic vulcanization with different loading of calcium carbonate (CaCO3) on linear low density polyethylene/natural rubber using N,N’-m-phenylene bismaleimide (HVA-2) vulcanized and dicumyl peroxide (DCP) vulcanized as a cross-linker were investigated. Optimum ratio of LLDPE/NR blends was chosen is 70/30 in this study. Calcium carbonate loading was varied at 0wt%, 5wt%, 10wt% and 20wt% as filler in LLDPE/NR blends. The study showed that the tensile properties of the un-vulcanized LLDPE/NR blends were deteriorated with increasing in CaCO3 content. The dynamic vulcanization approach by using the HVA-2 and DCP dynamic vulcanization agents was applied on the LLDPE/NR blends in order to compensate the deterioration properties caused by the incorporation of CaCO3. According to the results, the addition of HVA-2 and DCP showed the composites were better in water resistance and tensile properties as compared to the standardized counterpart. The morphological analysis by using the scanning electron microscopy (SEM) found out that the interfacial adhesion and dispersion of CaCO3 was improved in both vulcanization systems.
The effect of graphite flakes (GFs) and hybrid graphene nanoplatelets (GNPs) particles to the mechanical properties of epoxy composites
Authors: Bakar Nurhazwani Abu , Zulkarnain Mohd Arif , Hassan Wan Anuar Wan , Junid Ramli , Razak Jeefferie Abdul , Ismail Mohd Muzafar
Published: November 2020

This paper reports the effects of epoxy when reinforced with graphite flakes (GFs) and was compared to epoxy reinforced by hybrid reinforcements consisted of graphite flakes (GFs) and graphene nanoplatelets (GNPs). DGEBA, the type of epoxy which has been used in this work was added with 2, 4 and 6 wt.% of reinforcement respectively, relative to the total weight of the mixture. Nanocomposites was prepared using mechanical stirrer, stirred at 2000 rpm for 30 minutes followed by curing in the oven. The flexural testing shows that the epoxy/GFs composites has higher modulus compared to epoxy/GFs+GNPs. At 4wt.% filler loading, epoxy containing GFs exhibited 132% enhancement of modulus relative to neat epoxy. At the same filler amount, epoxy containing GFs+GNPs demonstrated slightly lower magnitude than system containing GFs with only 27% increase in modulus. However, addition of higher filler loading to the epoxy resin caused the modulus to decrease in magnitude speculated due to agglomeration of particles within the host matrix. The Charpy impact testing indicated similar pattern with epoxy/GFs system exhibited higher capability in absorbing energy than epoxy/GFs+GNPs where the peak was obtained at 4wt.% filler loading. At this amount of filler, 18.36 J/m increase in energy absorbed was recorded for epoxy/GFs compared to 2.13 J/m increased for epoxy/GFs+GNPs composite. Higher amount of filler loading added into epoxy only deteriorate the impact energy absorb by the sample. The hardness test show similar pattern of result with epoxy/GFs shows higher resistance in scratching compared to epoxy/GFs+GNPs.
Morphology and Conductive Properties of Carbon Black- and Graphite- Filled Conductive E poxy Micro-porous
Authors: Leemsuthep Anusha , Zakaria Zunaida , Lan Du Ngoc Uy
Published: November 2020

Conductive composite requires a well dispersion of conductive filler, which is this difficult to be achieved low content of filler for high density conductive filler. This work investigates the effect of carbon black and graphite on the morphology and conductive properties of conductive epoxy micro-porous. The conductive epoxy micro-porous was prepared by using single emulsion technique. It involved the drop of epoxy-hardener-blowing agent-conductive filler mixture into corn oil at 160 °C and followed by the leaching process to remove excess corn oil. Results show the addition of conductive filler in epoxy matrix lead to increases porous structure in epoxy micro-porous. Carbon black filled epoxy micro-porous possessed smaller particles compared to graphite filled epoxy micro-porous. For skeleton density and total pore, both of the value increase with filler loading due to packing sphere effect. However, the skeleton density for carbon black filled epoxy micro-porous is higher compared to graphite filled epoxy micro-porous. For electrical conductivity, graphite filled micro-porous was higher than that of carbon black filled epoxy micro-porous.
Effect of Porosity and Water Absorption on Compressive Strength of Fly Ash based Geopolymer and OPC Paste
Authors: Razak SitiAisyah , Zainal Farah Farhana , Shamsudin Shaiful Rizam
Published: November 2020

The fly ash based geopolymer is a promising binder by activation of fly ash with an alkaline activating solution. The fly ash based geopolymer prepared was characterized by several methods. The experimental result, studies effect of the porosity and water absorption on compressive strength of fly ash based geopolymer and Ordinary Portland Cement paste for comparison. The porosity studies were determined using the Brunauer, Emmett and Teller method included nitrogen adsorption / desorption plots. Then followed by water absorption and compressive strength tested at 7 and 28 days curing time. The result shows that the porosity of fly ash based geopolymer paste was in the lower surface area, pore volume and pore size compared to Ordinary Portland Cement paste. The small pore size of the fly ash based geopolymer had a significant proportion of a micropores whilst Ordinary Portland Cement paste pores were mostly mesopores. The highest compressive strength of fly ash-based geopolymer can be achieved up to 76.723 MPa at 28 days when less of pore size and water absorption. Therefore, the paste based on geopolymeric materials is a better durability and high resistance to aggressive environment compared Ordinary Portland Cement paste.
A short review: Properties of superconducting solder
Authors: Chang M.S. , Mohd Salleh M.A.A. , Halin D.S.C.
Published: November 2020

Development of electronic devices were moving towards miniaturization, multifunction and increasingly specific service environment of solder interconnects, where this drive to the higher requirements on the solder properties. Without solder, it would be impossible to produce the infinite electronic devices that define the 21st century. Hence, solder is important in the design and engineering process. This review paper was summarized on the literature of the low-temperature solder systems for superconducting solder materials, which provide further theoretical basis for the study of superconducting solder of electronic and aerospace applications. Pb-Bi system is the most satisfactory solder as a superconducting solder, but due to the restrictions of the lead usage, so new Pb-free superconducting solder need to be invented. Of those Pb-free superconducting materials had been studied, the Sn-In-Bi ternary solder system show the greatest superconducting properties as compared to other Pb-free superconducting solder where TC = 6.9 K, HC2 (4.2 K) = 0.18 T and JC (4.2 K, 0.01 T) = 1.3 × 108 A/m2 respectively.
Multifunctional efficiency metric for structural supercapacitors
Authors: Zhou Tianyang , Dickinson Emma , Boyd James G , Lutkenhaus Jodie L , Lagoudas Dimitris C
Published: November 2020

A new energy-based multifunctional efficiency (MFE) metric is developed using micromechanics solutions for structural supercapacitors consisting of composite electrodes that can store electrical energy and sustain mechanical loads. MFE metrics quantify the volume and/or mass savings when structural and functional materials are replaced by multifunctional materials and evaluate the trade-off between different functionalities. Commonly used multifunctionality metrics for structural supercapacitors are based on the rule of mixtures for both mechanical and electrical performance. These metrics provide an adequate approximation for some electrode geometries and loading conditions, such as longitudinal direction for aligned fibers in multifunctional composite electrodes and in-plane directions for laminate composite electrodes. However, if supercapacitors with complex microstructure or multiple electrode materials encompass more complex geometries or orientations of the structural and functional phases, a more comprehensive method is required to accurately capture the MFE. The MFE proposed herein can account for complex geometries and different mechanical loading conditions by using micromechanics methods. The shapes considered here include layered composite supercapacitors, fibrous films and any shape that can be derived from an ellipsoid. When calculated utilizing the proposed metric, the MFE varies by orders of magnitude due to the difference in shapes and applied mechanical fields to the supercapacitors, while existing metrics provide a constant upper bound. The influence of Young’s modulus difference between multifunctional electrodes and solid electrolytes is also discussed.
Quantifying the roles of space and stochasticity in computer simulations for cell biology and cellular biochemistry
Authors: Johnson M. E. , Chen A. , Faeder J. R. , Henning P. , Moraru I. I. , Meier-Schellersheim M. , Murphy R. F. , Prüstel T. , Theriot J. A. , Uhrmacher A. M.
Published: November 2020

As computational power and speed continue to increase at a remarkable rate, the dream of a fully comprehensive computational model of a living cell may be drawing closer to reality, but our analysis demonstrates that it will be crucial to evaluate the accuracy of such models critically and systematically.
Occupational Exposure during Asphalt Paving—Comparison of Hot and Warm Mix Asphalt in Field Experiments
Authors: Olsen Raymond , Graff Pål , Daae Hanne Line , Bryngelsson Ing-Liss , Molander Paal , Ellingsen Dag G
Published: November 2020

Objectives

Several studies have demonstrated an increased risk of adverse health effects, including reduced lung function and lung cancer among asphalt pavers, which has been related to occupational exposure to contaminants during asphalt paving. Consequently, occupational exposure among asphalt pavers must be reduced. The aim of this study was to compare the impact of hot mix asphalt (HMA) and warm mix asphalt (WMA) paving on occupational exposure levels during road paving in field experiments. Asphalt temperatures when paving with WMA are usually lower than when paving with HMA due to differences in the asphalt’s composition and method of application.

Methods

On 11 different road sections, one lane was paved with WMA and one with HMA during the same work shift under approximately identical weather conditions. The weather conditions and asphalt surface temperature were monitored during paving. Fifty-seven samples of fumes and vapor, organic and elemental carbon, amines, and respirable, thoracic, and inhalable particulate matter (PM) fractions were collected by stationary sampling. In addition, 30 samples of fumes and vapor were collected by personal sampling

Results

Compared to paving with HMA, paving with WMA significantly (P < 0.05; paired Student’s t-test) reduced the geometric mean (GM) air concentration of asphalt vapor (0.04 versus 0.08 p.p.m.), organic carbon (OC; 0.09 versus 0.18 mg m−3), and respirable PM (0.12 versus 0.22 mg m−3). Additionally, the air concentration of OC correlated strongly with the respirable fraction of PM (Pearson’s correlation coefficient 0.83).

Conclusions

Measured airborne concentrations of respirable PM, OC, and asphalt vapor were lower when paving with WMA than with HMA. Because exposure to airborne contaminants generated during asphalt paving is believed to be responsible for the adverse health effects observed among asphalt pavers, paving with WMA rather than HMA may have health benefits.
Nontestability of instrument validity under continuous treatments
Authors: Gunsilius F F
Published: November 2020

This note presents a proof of the conjecture in Pearl (1995) about testing the validity of an instrumental variable in hidden variable models. It implies that instrument validity cannot be tested in the case where the endogenous treatment is continuously distributed. This stands in contrast to the classical testability results for instrument validity when the treatment is discrete. However, imposing weak structural assumptions on the model, such as continuity between the observable variables, can re-establish theoretical testability in the continuous setting.
Biopsy forceps disruption paired with bougie dilation of esophageal strictures lengthens time to repeat intervention
Authors: Hengehold Tricia , Rogers Benjamin D , Quader Farhan , Gyawali C Prakash
Published: November 2020

Esophageal strictures commonly cause dysphagia and require treatment with endoscopic dilation using balloons or bougies. We aimed to determine whether biopsy forceps disruption of strictures at time of dilation increases time to repeat intervention or duration of intervention-free follow-up. We performed a retrospective analysis of 289 adults (age 61.0 ± 0.8 years, 66.4% female) who underwent dilation of an esophageal stricture at our tertiary care center between 2014 and 2016. Exclusions consisted of endoscopic intervention within the preceding 6 months, prior foregut neoplasia, achalasia, radiofrequency ablation, endoscopic mucosal resection, endoscopic submucosal dissection, or foregut surgery. Demographics, clinical presentation, dilation technique, and follow-up were abstracted from electronic medical records. We compared time to repeat dilation and duration of intervention-free follow-up between treatment subgroups. Balloon dilation was performed more often than bougie dilation (76.8 vs. 17.6%); biopsy forceps disruption was performed in 23.2%. Over a median follow-up of 52.9 months, 135 patients (46.7%) underwent repeat dilation. Age, body mass index, gender, and use of antisecretory medications did not influence need for repeat dilation (P = ns for each). Bougie dilation with biopsy forceps disruption prolonged time to repeat dilation in all patients (P ≤ 0.02), particularly in those with gastroesophageal reflux disease (P ≤ 0.03), compared with bougie dilation alone and balloon dilation with or without disruption. On Kaplan–Meier analysis, bougie dilation with biopsy forceps resulted in longer intervention-free follow-up compared with dilation alone (P = 0.03). We conclude that stricture disruption with biopsy forceps increases time to repeat intervention with bougie but not balloon dilation.
Magnetic hysteresis of magnetite, pyrrhotite and hematite at high temperature
Authors: Dunlop David J
Published: November 2020

The magnetic properties of iron-bearing minerals at above-ambient temperatures control their magnetic expression at depth in the Earth and other planets, as well as the permanent memory they retain as thermoremanence or thermochemical remanence when brought to the surface and cooled. This paper reports magnetic hysteresis parameters measured at temperatures up to the Curie point TC for natural pyrrhotite and hematite and for suites of sized magnetites, both natural and synthesized. Domain structure changes can be inferred from the ratio of saturation remanence Mrs to saturation magnetization Ms. In almost all magnetites and pyrrhotites studied, Mrs decreases more rapidly with increasing measurement temperature T than Ms, indicating thermal unblocking or vortex development in single-domain grains and addition or remobilization of domain walls at high T in multidomain grains. During cooling of a rock, iron minerals might then denucleate domains or vortices. Coercive force Hc, a measure of stability against changing magnetic fields, also decreases with increasing measurement T, usually at a rate similar to that of Mrs, but often retains a finite value near the Curie point.
Predicting clinical response to costimulation blockade in autoimmunity
Authors: Edner Natalie M , Wang Chun Jing , Petersone Lina , Walker Lucy S K
Published: November 2020

Curbing unwanted T cell responses by costimulation blockade has been a recognised immunosuppressive strategy for the last 15 years. However, our understanding of how best to deploy this intervention is still evolving. A key challenge has been the heterogeneity in the clinical response to costimulation blockade, and an inability to predict which individuals are likely to benefit most. Here, we discuss our recent findings based on the use of costimulation blockade in people with type 1 diabetes (T1D) and place them in the context of the current literature. We discuss how profiling follicular helper T cells (Tfh) in pre-treatment blood samples may have value in predicting which individuals are likely to benefit from costimulation blockade drugs such as abatacept.