bluuebunny/crossref_metadata_2025 huggingface dataset:
Weakly coupled synthetic antiferromagnetic nanodisks with perpendicular magnetic anisotropy for lab-on-chip devices
Authors: Welbourne Emma N. , Vemulkar Tarun , Petit Dorothée C. M. C. , Cowburn Russell P.
Published: September 2021

Synthetic antiferromagnetic particles with perpendicular magnetic anisotropy offer a highly desirable platform for use in fluidic applications. This work illustrates their high level of switching field tunability and demonstrates the ability to use particle design to overcome unfavorable hysteretic changes during patterning to manufacture functional, low switching field nanodisks. This makes them ideal candidates for lab-on-chip technologies such as microfluidic sorting or detection devices.
Fabrication of TiOx/Sb2Se3/p-NiOx photocathode for efficient photoelectrochemical water reduction
Authors: Li Peiyuan , Yuan Xiangbao , Feng Menglei , Ran Feng , Zhang Dingke , Chen Shijian
Published: September 2021

Photoelectrochemical (PEC) water splitting directly converts solar energy into clean and sustainable hydrogen energy, representing a promising and effective technique for solving the world's energy crisis. A hole transfer layer (HTL) plays a vital role for extracting holes from a semiconductor layer to a back electrode in PEC cells for water splitting. In this work, a TiOx/Sb2Se3/NiOx photocathode was fabricated by using p-NiOx as HTL. We show that the electrical properties of NiOx films can be well adjusted by the pulsed laser deposition technique. By systematically adjusting the electrical properties of the NiOx HTL and passivating the surface defects through coating with the TiOx layer, we achieved a high photocurrent density of up to −18.08 mA cm−2 at 0 V vs a reversible hydrogen electrode (RHE), an onset potential of 0.43 V vs RHE, and a half-cell solar to hydrogen conversion efficiency of 1.01% for the TiOx/Sb2Se3/NiOx photocathode. This work demonstrated NiOx as a potential hole transport material for a cost-effective Sb2Se3 PEC cell.
Dispersion relation for gauge-free electromagnetic drift kinetics
Authors: Zonta Filippo , Iorio Riccardo , Burby Joshua W. , Liu Chang , Hirvijoki Eero
Published: September 2021

Recently, a new approach to gyrokinetics, invariant under electromagnetic gauge transformations, was developed. The gyrocenter equations of motion are now expressed in terms of the perturbed fields instead of the potentials, in a form suitable for numerical simulations and analytic studies. In this paper, we verify that the long-wavelength limit, i.e., the drift-kinetic limit of the new gyrokinetic theory, is in line with existing work, providing a solid foundation for simulations. We compute the dispersion relation of the new drift-kinetic theory in slab geometry and find agreement with a long-wavelength limit of the full Vlasov–Maxwell model.
Behavior of Li-ion on the surface of Ti3C2–T (T = O, S, Se, F, Cl, Br) MXene: Diffusion barrier and conductive pathways
Authors: Papadopoulou Konstantina A. , Parfitt David , Chroneos Alexander , Christopoulos Stavros-Richard G.
Published: September 2021

After obtaining Ti3C2 MXene structures terminated with O, S, Se, F, Cl, and Br, we calculate the energy barrier for Li-ion diffusion on the surface of each MXene, being the first to report on the Li-ion diffusivity in Cl and Br terminated Ti3C2. We find that the Ti3C2Cl2 MXene has the lowest diffusion barrier, substituting the Ti3C2S2 reported in the literature so far. In addition, a study on the adsorption energies indicates that the top binding position is the most stable adsorption position for the Li-ion. Furthermore, it is shown that the adsorption energy depends on the electronegativity of the termination atoms, as well as the distance between the terminations, the Li, and the surface Ti-atoms. Finally, we show that the bond valence sum method provides an indication of the transition state of the Li-ion and can serve as a comparison tool for the diffusion barriers of different structures.
Particle resonances in stellarators
Authors: White Roscoe , Ethier Stephane
Published: September 2021

Resonances of high energy particles in magnetic confinement devices due to electromagnetic instabilities can strongly modify the particle distribution, leading to a reduction in fusion power and even discharge termination and particle loss to the device walls through an avalanche. The existence of a mode particle resonance depends on the properties of the equilibrium and particle parameters, and their number, location, and density can vary with device design. Recently, the advent of more powerful computing capabilities and advanced theoretical understanding has led to the design of non-axisymmetric devices or stellarators, which could prove to be more advantageous than tokamaks. Stellarators have the advantage of being immune to major disruptions because of the very low plasma current. One of the problems shared by both types of devices is the existence of resonances in particle orbits, which can lead to large amplitude high frequency instabilities and subsequent induced particle loss. We examine the number of resonances, their location, and dependence on particle energy for some stellarator designs.
Thermodynamical analysis and constitutive equations for a mixture of viscous Korteweg fluids
Authors: Gorgone Matteo , Oliveri Francesco , Rogolino Patrizia
Published: September 2021

A complete thermodynamical analysis for a binary mixture of viscous Korteweg fluids with two velocities and two temperatures is developed. The constitutive functions are allowed to depend on the diffusion velocity and the specific internal energies of both constituents, together with their first gradients, on the symmetric part of the gradient of barycentric velocity as well as on the mass density of the mixture and the concentration of one of the constituents, together with their first and second gradients. Compatibility with the entropy principle is analyzed by applying the extended Liu procedure, and a complete solution of the set of thermodynamical restrictions is recovered in three space dimensions. Finally, the equilibrium configurations are investigated, and it is proved that no restrictions arise on the admissible phase boundaries. The theoretical results here provided may serve as a basis for experimental and/or numerical investigations, in particular for determining the surface levels of phase boundaries at equilibrium and making a comparison with the experimental profiles.
Predicting the optimal field enhancement factor during the growth of arched fibers
Authors: Assis Thiago A. de , Dall'Agnol Fernado F. , Cahay Marc
Published: September 2021

Curved carbon-based fibers, in the form of looped fibers, have been investigated as promising field electron emitters with high mechanical stability. Recently, the growth of semicircular arched carbon nanofibers (structures when the arch is incomplete) has received increased attention due to their potential application in next-generation electronic devices. In this Letter, we theoretically investigate the field enhancement factor (FEF) during the growth of these structures. We found the conditions for the optimal FEF, γmax, as a function of the geometrical parameters. Our results show that the local characteristic FEF at the top of the arch obeys a scaling law, γC≈γmax×Ω[(ψ/ψ*)2], where Ω is a nearly quadratic function of (ψ/ψ*), where ψ is a normalized arch angle of the fiber and ψ* is the ψ-value when γC=γmax. Importantly, our results show a universal behavior for γmax, namely, γmax≈κ[(R/r)α−0.45]ρ (where r and R are the radii of the fiber and the arch, respectively), α≡Rrim/r (where Rrim is the radius of the rim at the fiber top), and κ and ρ are positive constants. We point out several advantages of the arched fiber over the fully looped fiber for field emission devices, particularly the mechanical stability of the two-stage arched structures. Finally, starting with the conditions for γmax inferred from an isolated arch, the effects of electrostatic depolarization in regular arrays of arched fibers are analyzed as a function of the lattice parameters.
Bottom-up synthesis of graphene films hosting atom-thick molecular-sieving apertures
Authors: Villalobos Luis Francisco , Van Goethem Cédric , Hsu Kuang-Jung , Li Shaoxian , Moradi Mina , Zhao Kangning , Dakhchoune Mostapha , Huang Shiqi , Shen Yueqing , Oveisi Emad , Boureau Victor , Agrawal Kumar Varoon
Published: September 2021

Significance

The energy efficiency of gas separation is expected to benefit from the development of membranes yielding selective but large permeance. The ultimate limit of this is two-dimensional films hosting a high density of molecular-selective apertures (e.g., nanoporous single-layer graphene). Currently, pores are incorporated in single-layer graphene by postsynthetic etching route, and the direct bottom-up synthesis of nanoporous graphene, especially targeting a high pore density, remains a grand challenge attributing to a number of crystallization bottlenecks. We address this by increasing the density of molecular-sized intrinsic vacancy defects in graphene by developing crystallization conditions which promote the growth of misoriented grains, limiting the grains to a few nanometers in size and preventing a complete grain intergrowth while yielding mechanically robust films.
Effect of CeO2 on the elevated-temperature wear behaviour of in situ TiB2/A356 composite
Authors: Yu Xiaojie , Yao Mingxiao , Xue Jing , Lei Junbo
Published: September 2021

Effects of CeO2 on the wear resistance of in situ TiB2/A356 composites synthesised via the reaction of K2TiF6, KBF4 and Al melt were investigated. The results showed that CeO2 was effective in enhancing the wear resistance of TiB2/A356 at all test temperatures. The CeO2 pushed the transition temperature from mild to severe wear by another 50°C. The wear mode of the composite without CeO2 was metal flow and severe wear at 90 N and 200°C, while for the composite with CeO2, the oxidation and delamination wear was the main wear mode at the same load and temperature. The improvement in the wear resistance of the composite was attributed to the increase in thermal stability of the composite due to improved TiB2 dispersion by adding CeO2.
How do batrachotoxin-bearing frogs and birds avoid self intoxication?
Authors: Márquez Roberto
Published: September 2021

Abderemane-Ali et al. investigated the mechanisms underlying self-resistance in poison dart frogs and poison birds.
Fused silica cylindrical shell resonators with 25 million Q factors
Authors: Zeng Libin , Pan Yao , Luo Yiming , Xiao Pengbo , Liu Jianping , Tan Zhongqi , Yang Kaiyong , Luo Hui
Published: September 2021

The Q factors of fused silica cylindrical shell resonators reaching 25 million is reported. The finite element method is employed to analyze the anchor loss and chemical etching is used to reduce the surface loss of cylindrical resonators. Two resonators with the same processing parameters are etched for 13 rounds with each round set as 5 min. After each round of chemical etching, the surface roughness, Q factors and resonant frequencies of the two resonators are measured. The Q factors of the two cylindrical resonators have both exceeded 25 million, reaching the level of that of fused silica hemispherical resonators. Results also indicate that the Q factors of fused silica cylindrical resonators are not related with their surface roughness. This study shows the potential of the cylindrical resonator gyroscope to achieve the same degree of precision as the hemispherical resonator gyroscope, which has presented outstanding performances.
Broad background in electron diffraction of 2D materials as a signature of their superior quality
Authors: Petrović Marin , Meyer zu Heringdorf Frank J , Hoegen Michael Horn-von , Thiel Patricia A , Tringides Michael C
Published: September 2021

An unusually broad bell-shaped component (BSC) has been previously observed in surface electron diffraction on different types of 2D systems. It was suggested to be an indicator of uniformity of epitaxial graphene (Gr) and hexagonal boron nitride (hBN). In the current study we use low-energy electron microscopy and micro-diffraction to directly relate the BSC to the crystal quality of the diffracting 2D material. Specially designed lateral heterostructures were used to map the spatial evolution of the diffraction profile across different 2D materials, namely pure hBN, BCN alloy and pure Gr, where the alloy region exhibits deteriorated structural coherency. The presented results show that the BSC intensity has a minimum in the alloyed region, consequently showing that BSC is sensitive to the lateral domain size and homogeneity of the material under examination. This is further confirmed by the presence of a larger number of sharp moiré spots when the BSC is most pronounced in the pure hBN and Gr regions. Consequently, it is proposed that the BSC can be used as a diagnostic tool for determining the quality of the 2D materials.
Invariant manifold of modified solitons for the perturbed sine-Gordon equation
Authors: Mashkin Timur
Published: September 2021

We study the perturbed sine-Gordon equation θ

tt
− θ

xx
+ sin θ = F(ɛ, x), where we assume that the perturbation F is analytic in ɛ and that its derivatives with respect to ɛ satisfy certain bounds at ɛ = 0. We construct implicitly an, adjusted to the perturbation F, manifold which is invariant in the following sense: the initial value problem for the perturbed sine-Gordon equation with an appropriate initial state on the manifold has a unique solution which follows a trajectory on the manifold. The trajectory is precisely described by two parameters which satisfy specific ODEs. In our approach, the invariant manifold is generated as a limit of a sequence whose elements are created one after another by successive distortion of the classical solitary manifold. For the proof, we firstly modify the iteration scheme introduced in Mashkin (2020 Stability of the solitary manifold of the perturbed sine-Gordon equation J. Math. Anal. Appl.
486 123904). By using the modified iteration scheme we build the mentioned sequence. Thereafter we show convergence of the sequence to establish the result.
Thermally tunable hydrogel crosslinking mediated by temperature sensitive liposome
Authors: Tasnim Tasmia , Adkins Michael D , Lim Taehwan , Feng Haidong , Magda Jules J , Shea Jill E , Agarwal Jayant , Furse Cynthia M , Zhang Huanan
Published: September 2021

Hydrogel crosslinking by external stimuli is a versatile strategy to control and modulate hydrogel properties. Besides photonic energy, thermal energy is one of the most accessible external stimuli and widely applicable for many biomedical applications. However, conventional thermal crosslinking systems require a relatively high temperature (over 100 °C) to initiate covalent bond formation. To our knowledge, there has not been a thermally tunable hydrogel crosslinking system suitable for biological applications. This work demonstrates a unique approach to utilize temperature sensitive liposomes to control and modulate hydrogel crosslinking over mild temperature range (below 50 °C). Temperature sensitive liposomes were used to control the release of chemical crosslinkers by moderate temperature changes. The thermally controlled crosslinker release resulted in tunable mechanical and transport properties of the hydrogel. No significant inflammable response observed in the histology results ensured the biocompatibility of the liposome-mediated crosslinkable hydrogel. This work opens new opportunities to implement thermal energy system for control and modulate hydrogel properties.
Checkered landscapes: hydrologic and biogeochemical nitrogen legacies along the river continuum
Authors: Liu J , Van Meter K J , McLeod M M , Basu N B
Published: September 2021

Decades of agricultural intensification have led to elevated stream nitrogen (N) concentrations and eutrophication of inland and coastal waters. Despite widespread implementation of a range of strategies to reduce N export, expected improvements in water quality have not been observed. This lack of success has often been attributed to the existence of legacy N stores within the landscape. Here, we use the ELEMeNT-N model to quantify legacy accumulation and depletion dynamics over the last century (1930–2016) across 14 nested basins within the Grand River Watershed, a 6800 km2 agricultural watershed in the Lake Erie Basin. Model results reveal significant legacy N accumulation across the basin, ranging from 705 to 1071 kg ha−1, creating a checkered landscape of N legacies. The largest proportion (82%–96%) of this accumulated N is stored in soil organic N reservoirs, as biogeochemical legacy, and the remaining in groundwater, as hydrologic legacy. The fraction of N surplus accumulated in soil and groundwater is most strongly correlated with the calibrated watershed mean travel time µ, with the accumulation increasing with increases in µ. The mean travel time ranges from 5 to 34 years across the watersheds studied, and increases with increase in tile drainage, highlighting the strong control of anthropogenic management on legacy accumulation. Water quality improvement timescales were found to be heterogeneous across the watersheds, with greater legacies contributing to slower recovery.
What causes Ngancar River in Wiroko Temon sub-watershed vulnerable to flooding?
Authors: Prastica R M S , Fanani A J
Published: September 2021

The vulnerability to flooding becomes a concern in every region to optimize the mitigation strategy, hence the disaster impact can be reduced from the environment. What factors become the main triggering issue toward water-related disasters? Every region has a different answer. Can a river that does not have historical flood events become vulnerable to flood today? This study investigates the flooding factors in Ngancar River, Wiroko Temon sub-watershed, Wonogiri. The research employs hydrological and hydraulics analysis. The results reveal that Ngancar River experienced land-use changes over time which lead to the dynamic of the discharge return period being bigger. As a result, river capacity today cannot accommodate the flooding volume. The research concludes that the hydraulics condition needs to be improved for flood mitigation. Further hydrological analysis is suggested to be conducted.
Sustainable principles in designing Lombok’s Beachside Area: a Gading Beach case study
Authors: Kamase G A P P , Saptaningtyas R S , Handayani T
Published: September 2021

Recognized as a global best halal tourism, Lombok in West Nusa Tenggara (NTB) is anticipating significant tourism growth. As a response to this, the local government are trying to accelerate the supporting facilities for tourism development, including the Gading Beach area. On contrary, however, buildings are known among the world’s biggest energy consumption. Therefore, the design proposal of these new buildings in the Gading Beach area ought to consider a holistic sustainable approach to create buildings that will encourage environmental, social and economic benefits. Five key sustainable design principles were utilized for the development of the Gading Beach area. Those principles are including site and ecology, community and culture, health, materials and energy. The implementation of these design strategies in the Gading Beach area is expected to exhibit an effective application of a sustainable approach in beachside buildings.
Effectiveness Vetiveria zizanoides plant in ability absorption of heavy metals in coal mining waste
Authors: Andrawina A , Ernawati R , Cahyadi T A , Bargawa W S , Amri N A , Ferdian I
Published: September 2021

Vetiveria zizanoides plants have considerable potential for phytoremediation, because these plants show relatively high ability to accumulate and translocate heavy metals in wetlands and are able to tolerate acidic water pH. The results of the study showed that the Vetiveria zizanoides plant has a fairly good survival rate in acid mine water conditions and has a fairly high ability to absorb Fe, Mn and sulfur metals. This is evidenced by the treatment of Vetiveria zizanoides plants by planting 20 Vetiveria zizanoides stems into acid mine water media without the addition of organic substrates, seen on day 20 after treatment of 20 Vetiveria zizanoides stems there was only 1 plant that died, the rest still survive in acidic water conditions. In this treatment, the Vetiveria zizanoides plant was able to absorb Fe, Mn and sulfur with an efficiency increase of 93% for Fe metal, 40% for Mn metal and 43% sulfur for 20 days. However, to improve the quality of acid water in this treatment, it was not optimal, so treatment was given with a combination of Vetiveria zizanoides and organic substrates. Treatment 3 was the most effective in improving acid mine water quality, because it had an average effectiveness of 58% for increasing the pH of the air and 97% for decreasing the concentration of Fe and Mn metals. With the efficiency of increasing the metal concentration in plants by 16% for Fe metal, 29% for Mn metal and 35% sulfur for 20 days after being given treatment.
Effect of addition polyethylene glycol on morphology and functional groups of composite films bacterial nanocellulose - graphite nanoplatelets
Authors: Susilo B D , Suryanto H , Aminnudin A
Published: September 2021

Polyethylene Glycol (PEG) existence on the composite film bacterial nanocellulose (BNC) reinforced with graphite nanoplatelets (GNP) has been analyzed in this research. Pineapple peel waste extract was used to synthesis the bacterial cellulose (BC) pellicle. A 1% NaOH solution was used to remove impurities from the BC pellicle. Mechanical disintegration and a high-pressure homogenization method were used to synthesize BNC. The high-pressure homogenizer (HPH) runs for five cycles at 150 bar before being filtered with a vacuum filter. The composite films are synthesized using a mixture of BNC, PEG 1%, and GNP 2.5%. Then the mixed slurry was dried using an oven for 14 hours at a temperature of 80 degrees Celsius. The morphology of composite BNC film was observed by using SEM. The addition of PEG causes the BC structure to become more porous. GNP is not well distributed in the BNC matrix but still acts as a dispersed filler. FTIR analysis is conducted to see its functional groups. The addition of GNP caused the hydroxyl group to be significantly reduced.
Kinetics and thermodynamics study of organic waste combustion using thermogravimetric analysis
Authors: Sukarni S , Prasetiyo A , Fidiah L , Permanasari A A , Puspitasari P
Published: September 2021

Urban waste in Malang becomes a significant problem due to its increasing volume and negative impact on the environment. An incineration process offers a solution to reduce waste. The thermochemical method is one of the routes to reduce waste volume effectively. This paper discussed the combustion of organic waste with thermogravimetric analysis in a nonisothermal mode in which temperature escalated from 25 to 1000°C by a heating ramp of 20°C/min. The process of burning organic waste is divided into three steps of decomposition, namely the step of moisture loss, decomposition and combustion of volatile matter and fixed carbon, and the final step of ash decomposition from the residual matters. The kinetic parameters calculated using the Coats-Redfern method at the main combustion step, resulting in activation energy of 99.37 kJ/mol and a pre-exponential factor of 6.01E+08/s.
Physicochemical properties and porosity of coconut chell waste (CSW) biomass
Authors: Prasetiyo A , Sukarni S , Irawan A , Permanasari A A , Puspitasari P
Published: September 2021

Utilizing waste biomass as a reserve energy source can play an essential role in reducing expanding fossil fuel’s environmental impact. This paper presented an analysis of physical, chemical, morphological, calorific values and porosity of biomass from coconut shell waste (CSW) as an alternative for biofuel feedstock. The physical properties of CSW biomass were dominated by volatile matter and fixed carbon content of 73.8 and 22.7 (wt.%, DB), respectively. The calorific value is 20.39 MJ/kg, giving a significant energy effect when the biomass is burned. The chemical properties of CSW biomass were dominated by C and O content of 41.04 and 57.47 (wt.%), respectively, contributing most of the oxygen to the thermal process. However, most elements of chemical properties contributed to the formation of ash in the combustor, including minor and major elements (S, K, Si, Al, P, Cl, Ca, Mg, and Fe). Besides, they had a negative effect in the form of slagging in the combustion residue. The porosity analysis of CSW biomass was 67.30 – 72.92%, which was able to increase the size of char particles during the thermal process. The analysis of physicochemical properties and porosity of CSW biomass confirmed that this material could be beneficial as an alternative energy reserve in the future.
Characteristics and modeling kinetics of oil palm frond petiole pyrolysis using thermogravimetric analyzer
Authors: Prasetiyo A , Sukarni S , Wibowo A A , Permanasari A A , Puspitasari P
Published: September 2021

As one of the largest palm oil-producing countries globally, Indonesia produces abundant oil palm biomass; indeed, it brings large oil palm frond petiole (OPFP). OPFP is one of the oil palm biomass that can be converted into an energy source. This research focuses on analyzing thermal decomposition characteristics and pyrolysis kinetics of OPFP using thermogravimetric analysis (TGA). The results showed that the thermal decomposition of pyrolysis was divided into three steps, including the evaporation stage of moisture content, the releasing of volatile compounds and organic matter, and the final stage of lignin and tar decomposition. Both the activation energy and the pre-exponential factors were analyzed with the Coats-Redfern method in step II active pyrolysis zone are 80.56 kJ/mol and 7.21/min, respectively, as shown in the Chemical Reaction Order F1.5 model with the accuracy of a correlation coefficient of 0.99. These results provided the fundamental data useful for properly designing the reactor system for industrial purposes.
Assessment on biochemical oxygen demand (BOD) removal using treatment train system for agricultural run-off
Authors: Razak A A A , Takaijudin H , Osman M , Yusof K W , Ali W , Ishak S
Published: September 2021

Agricultural runoff is non-point source pollution that is unpredictable and difficult to control. Best Management Practices (BMPs) and Low Impact Development (LID) has been utilized as a method to manage agricultural runoff. Treatment train systems are LID-BMPs arranged in a series that aims to treat and manage agricultural runoff. This study focuses on the use of treatment train systems to reduce the concentration of BOD in agricultural runoff. A treatment train system was set up with three varying configurations to evaluate the efficiency of BOD removal. The three configurations consisted of no vegetation set which acts as the control, vegetated set, and vegetated set with the saturated zone. All three configurations showed good final removal rates of BOD at 56% for the control and 75% and 85% for both vegetated sets without and with the saturated zone. The control is classified classifying it as Class III according to Water Quality Standards, while both vegetated set without and with saturated zone had classified both sets as Class II and I, respectively. The performance of the treatment train system was compared to the use of a single bioretention system.
Angle of inclination and radiation intensity variation effects on the flat plate solar collector’s performance using graphene oxide (GO)-water nanofluid
Authors: Permanasari A A , Putra S A , Puspitasari P , Sukarni S , Zaine S N A , Wahyunengsih W
Published: September 2021

Flat Plate Solar Collector is a special heat exchanger instrument that transforms solar radiation energy into heat energy. Various attempts have been completed to improve the flat plate solar collector’s performance. One of them is by developing advanced heat transfer fluid with better thermophysical properties than base fluid. Further, the flat plate solar collector’s inclination angle and radiation intensity were investigated to identify the most optimal solar radiation angle of incidence. This study discusses the use of a 0.006% graphene oxide-water nanoparticle toward the nanofluid’s thermophysical properties, sufficient radiation intensity of flat plate solar collector performance, as well as the inclination angle of flat plate solar collector toward the collector’s performance. The used radiation intensity variations were 415 W/m2, 515 W/m2 and 615 W/m2. Meanwhile, the radiation used in this study was from a sun simulator 750 W/m2. In each radiation intensity variation, the inclination angle test of 30°, 45°, and 60° for the flat plate solar collector were carried out. This study was expected to discover the best performance of graphene oxide-water nanofluid usage, collector’s inclination angle variation, and radiation intensity variation.
Performance analysis of a H-Darrieus wind turbine for a Naca 0015 Airfoil: CFD and RSM-based design optimization
Authors: Permanasari A A , Budiearso A B , Sukarni S , Puspitasari P , Zaine S N A , Wahyunengsih W
Published: September 2021

With the increasing demand for electrical energy and the depletion of fossil fuel reserves, this situation forces humans to look for alternative renewable energy. The Indonesian region has a very large wind energy potential because it is located in the tropics. The wind turbine is alternative energy based on kinetic energy into electricity. The purpose of this study was to analyze the effect of the number of blades, wind speed, and angle of attack on turbine performance in the form of the efficiency of the H-Darrieus wind turbine using Airfoil NACA 0015. Variations used in this study were the number of blades (3; 4; 5 pieces) and angle of attack (5°; 15°; 25°). The method used in this research is the Computational Fluid Dynamics (CFD) method and the response surface methodology (RSM). The CFD method is used to find the moment pressure and tangential velocity values, while the RSM method is used to find the most optimum variation. The results of this study indicate that a wind turbine with a number of blades 3 pieces, and a turbine angle of attack 11º is the most optimum H-Darrieus wind turbine design with an efficiency of 5.38%.
The forecasting model of discharge at Brantas sub-basin using autoregressive integrated moving average (ARIMA) and decomposition methods
Authors: Idfi G , Yulistyorini A , Rahayuningsih T , Dewi V A K , Setyawan E
Published: September 2021

A watershed is a combination of several rivers and tributaries with certain boundaries that function to drain rainwater into a lake or a sea. One of the hydrological data contained in the watershed is discharge data. If there is incomplete discharge data, it must be extended based on historical data. ARIMA and decomposition are methods that can predict time series data. The purposes of this research are to determine the historical discharge patterns of Brantas Sub-basin, to know the discharge forecasting model of Brantas Sub-basin, to know the results of forecasting Brantas Sub-basin discharge, and to compare the accuracy between ARIMA and decomposition methods. The accuracy is obtained by calculating MSE and RMSE values. The best method is a method that has the smallest MSE and RMSE values. The results of the research showed that Brantas Sub-basin discharge data in 2007-2017 has a seasonal pattern. The best ARIMA model is ARIMA (0,0,3)(1,0,1)12 model, while the best decomposition model is the additive decomposition model. The Decomposition method has better accuracy than the ARIMA method in predicting discharge of Brantas Sub-basin.
Opioid-related emergency department visits and hospitalizations among patients with chronic gastrointestinal symptoms and disorders dually enrolled in the Department of Veterans Affairs and Medicare Part D
Authors: Balbale Salva N , Cao Lishan , Trivedi Itishree , Stulberg Jonah J , Suda Katie J , Gellad Walid F , Evans Charlesnika T , Jordan Neil , Keefer Laurie A , Lambert Bruce L
Published: September 2021

Purpose

We examined the prevalence of, and factors associated with, serious opioid-related adverse drug events (ORADEs) that led to an emergency department (ED) visit or hospitalization among patients with chronic gastrointestinal (GI) symptoms and disorders dually enrolled in the Department of Veterans Affairs (VA) and Medicare Part D.

Methods

In this retrospective cohort study, we used linked national patient-level data (April 1, 2011, to October 31, 2014) from the VA and Centers for Medicare and Medicaid Services to identify serious ORADEs among dually enrolled veterans with a chronic GI symptom or disorder. Outcome measures included serious ORADEs, defined as an ED visit attributed to an ORADE or a hospitalization where the principal or secondary reason for admission involved an opioid. We used multiple logistic regression models to determine factors independently associated with a serious ORADE.

Results

We identified 3,430 veterans who had a chronic GI symptom or disorder; were dually enrolled in the VA and Medicare Part D; and had a serious ORADE that led to an ED visit, hospitalization, or both. The period prevalence of having a serious ORADE was 2.4% overall and 4.4% among veterans with chronic opioid use (≥90 consecutive days). Veterans with serious ORADEs were more likely to be less than 40 years old, male, white, and to have chronic abdominal pain, functional GI disorders, chronic pancreatitis, or Crohn’s disease. They were also more likely to have used opioids chronically and at higher daily doses.

Conclusion

There may be a considerable burden of serious ORADEs among patients with chronic GI symptoms and disorders. Future quality improvement efforts should target this vulnerable population.
Prognostic value of Mortalin correlates with roles in epithelial–mesenchymal transition and angiogenesis in lung adenocarcinoma
Authors: Meng Ziqi , Zhang Rui , Wu Xuwei , Zhang Meihua , Zhang Songnan , Jin Tiefeng
Published: September 2021

Mortalin is involved in the malignant phenotype of many cancers. However, the specific molecular mechanisms involving Mortalin in lung adenocarcinoma remain unclear. In this study, we showed that both Mortalin mRNA and protein are overexpressed in lung adenocarcinoma. In addition, Mortalin overexpression was positively correlated with poor overall survival. In vitro experiments showed that Mortalin silencing inhibited the proliferation, colony formation and migration abilities of A549 and H1299 cells. Mortalin promotes EMT progression, angiogenesis and tumor progression by activating the Wnt/β-catenin signaling pathway. In vivo experiments further confirmed that Mortalin promoted malignant progression of lung adenocarcinoma. Taken together, our data suggest that Mortalin represents an attractive prognostic marker and therapeutic target in lung adenocarcinoma patients.
Automated quantification of vomeronasal glomeruli number, size, and color composition after immunofluorescent staining
Authors: Bahreini Jangjoo Shahab , Lin Jennifer M , Etaati Farhood , Fearnley Sydney , Cloutier Jean-François , Khmaladze Alexander , Forni Paolo E
Published: September 2021

Glomeruli are neuropil-rich regions of the main or accessory olfactory bulbs (AOB) where the axons of olfactory or vomeronasal neurons and dendrites of mitral/tufted cells form synaptic connections. In the main olfactory system, olfactory sensory neurons (OSNs) expressing the same receptor innervate 1 or 2 glomeruli. However, in the accessory olfactory system, vomeronasal sensory neurons (VSNs) expressing the same receptor can innervate up to 30 different glomeruli in the AOB. Genetic mutation disrupting genes with a role in defining the identity/diversity of olfactory and vomeronasal neurons can alter the number and size of glomeruli. Interestingly, 2 cell surface molecules, Kirrel2 and Kirrel3, have been indicated as playing a critical role in the organization of axons into glomeruli in the AOB. Being able to quantify differences in glomeruli features, such as number, size, or immunoreactivity for specific markers, is an important experimental approach to validate the role of specific genes in controlling neuronal connectivity and circuit formation in either control or mutant animals. Since the manual recognition and quantification of glomeruli on digital images is a challenging and time-consuming task, we generated a program in Python able to identify glomeruli in digital images and quantify their properties, such as size, number, and pixel intensity. Validation of our program indicates that our script is a fast and suitable tool for high-throughput quantification of glomerular features of mouse lines with different genetic makeup.
Short- and long-term outcomes in patients operated with total minimally invasive esophagectomy for esophageal cancer
Authors: Hauge Tobias , Førland Dag T , Johannessen Hans-Olaf , Johnson Egil
Published: September 2021

At our hospital, the main treatment for resectable esophageal cancer (EC) has since 2013 been total minimally invasive esophagectomy (TMIE). The aim of this study was to present the short- and long-term results in patients operated with TMIE. This cross-sectional study includes all patients scheduled for TMIE from June 2013 to January 2016 at Oslo University Hospital. Data on morbidity, mortality, and survival were retrospectively collected from the patient administration system and the Norwegian Cause of Death Registry. Long-term postoperative health-related quality of life (HRQL) and level of dysphagia were assessed by patients completing the following questionaries: EORTC QLQ-OG25, QLQ-C30, and the Ogilvie grading scale. A total of 123 patients were included in this study with a median follow-up time of 58 months (1–88 months). 85% had adenocarcinoma, 15% squamous cell carcinoma. Seventeen patients (14%) had T1N0M0, 68 (55%) T2-T3N0M0, or T1-T2N1M0 and 38 (31%) had either T3N1M0 or T4anyNM0. Ninety-eight patients (80%) received neoadjuvant (radio)chemotherapy and 104 (85%) had R0 resection. Anastomotic leak rate and 90-days mortality were 14% and 2%, respectively. The 5-year overall survival was 53%. Patients with tumor free resection margins of >1 mm (R0) had a 5-year survival of 57%. Median 60 months (range 49–80) postoperatively the main symptoms reducing HRQL were anxiety, chough, insomnia, and reflux. Median Ogilvie score was 0 (0–1). In this study, we report relatively low mortality and good overall survival after TMIE for EC. Moreover, key symptoms reducing long-term HRQL were identified.
Cervical cancer testing among women aged 30–49 years in the WHO European Region
Authors: Williams Julianne , Rakovac Ivo , Victoria Jocelyn , Tatarinova Tatiana , Corbex Marilys , Barr Ben , Rose Tanith , Sturua Lela , Obreja Galina , Andreasyan Diana , Shukurov Shukhrat , Gahraman Hagverdiyev , Mikkelsen Bente , Berdzuli Nino , Breda João
Published: September 2021

Background

Screening programs play an important role in a comprehensive strategy to prevent cervical cancer, a leading cause of death among women of reproductive age. Unfortunately, there is a dearth of information about rates of cervical cancer testing, particularly in Eastern Europe and Central Asia where levels of cervical cancer are among the highest in the WHO European Region. The purpose of this article is to report on the lifetime prevalence of cervical cancer testing among females aged 30–49 years from across the WHO European region, and to describe high-level geographic and socioeconomic differences.

Methods

We used data from the European Health Information Survey and the WHO STEPwise approach to Surveillance survey to calculate the proportions of women who were tested for cervical cancer.

Results

The percentage of tested women ranged from 11.7% in Azerbaijan to 98.4% in Finland, with the lowest percentages observed in Azerbaijan, Tajikistan and Uzbekistan. Testing was lower in Eastern Europe (compared to Western Europe), among low-income countries and among women with lower levels of education.

Conclusion

Effective cervical cancer screening programs are one part of a larger strategy, which must also include national scale-up of human papilloma virus vaccination, screening and treatment.
Humoral and cellular immunity and the safety of COVID-19 vaccines: a summary of data published by 21 May 2021
Authors: Xu Kun , Dai Lianpan , Gao George F
Published: September 2021

Coronavirus disease 2019 (COVID-19) has caused millions of deaths, and serious consequences to public health, economies and societies. Rapid responses in vaccine development have taken place since the isolation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the release of the viral genome sequence. By 21 May 2021, 101 vaccines were under clinical trials, and published data were available for 18 of them. Clinical study results from some vaccines indicated good immunogenicity and acceptable reactogenicity. Here, we focus on these 18 vaccines that had published clinical data to dissect the induced humoral and cellular immune responses as well as their safety profiles and protection efficacy.
Therapeutic immunoglobulin A antibody for dysbiosis-related diseases
Authors: Shinkura Reiko
Published: September 2021

Dysbiosis is alterations in the microbial composition compared with a healthy microbiota and often features a reduction in gut microbial diversity and a change in microbial taxa. Dysbiosis, especially in the gut, has also been proposed to play a crucial role in the pathogenesis of a wide variety of diseases, including inflammatory bowel disease, colorectal cancer, cardiovascular disease, obesity, diabetes and multiple sclerosis. A body of evidence has shown that intestinal polymeric immunoglobulin A (IgA) antibodies are important to regulate the gut microbiota as well as to exclude pathogenic bacteria or viral infection such as influenza and SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) at mucosal sites. Since the 1970s, trials for oral administration of therapeutic IgA or IgG have been performed mainly to treat infectious enteritis caused by pathogenic Escherichia coli or Clostridium difficile. However, few of them have been successfully developed for clinical application up to now. In addition to the protective function against intestinal pathogens, IgA is well known to modulate the gut commensal microbiota leading to symbiosis. Nevertheless, the development of therapeutic IgA drugs to treat dysbiosis is not progressing. In this review, the advantages of therapeutic IgA antibodies and the problems for their development will be discussed.
Pharmacological effects on anaplerotic pathways alter the metabolic landscape in the tumor microenvironment, causing unpredictable, sustained anti-tumor immunity
Authors: Udono Heiichiro , Nishida Mikako
Published: September 2021

To achieve sustained anti-tumor immunity, tumor-infiltrating effector CD8 T lymphocytes (CD8 TILs) must be able to produce cytokines, including IFNγ, and proliferate robustly within the local tumor tissue upon antigen recognition. IFNγ production by CD8 TILs depends on glycolysis, whereas their proliferation additionally requires oxidative phosphorylation (OxPhos). The level of OxPhos, and hence the oxygen consumption rate, depends on mitochondrial biogenesis and requires the loading of metabolic precursors into the tricarboxylic acid cycle to keep it functioning. This is referred to as anaplerosis. Recent advances in the field of immuno-metabolism have shown the impact of pharmacological agents on anaplerotic pathways, resulting in metabolic down-regulation in tumor cells; in contrast, the agents trigger sustained anti-tumor immunity by up-regulating both glycolysis and OxPhos in CD8 TILs. The opposing effects of pharmacological inhibition (and/or activation) on anaplerosis in tumor cells and CD8 TILs are unpredictable. Careful dissection of the underlying mechanism might confer important knowledge, helping us to step into a new era for cancer immunotherapy.
Using telemedicine to improve the quality of life of parents of infants with CHD surgery after discharge
Authors: Zhang Qi-Liang , Lei Yu-Qing , Liu Jian-Feng , Cao Hua , Chen Qiang
Published: September 2021

Objective

The purpose of this study was to investigate the effect of using telemedicine to improve the quality of life of parents of infants with congenital heart disease (CHD) surgery after discharge.

Methods

A prospective randomized controlled study was conducted in a provincial hospital in China from November 2020 to April 2021 to compare the quality of life of parents of infants with CHD surgery after discharge between the WeChat follow-up group and the outpatient follow-up group. A total of 84 patients (42 in each group) and 168 parents (84 in each group) participated in this study.

Results

One month after discharge, the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores of parents in the intervention group were significantly lower than those in the control group (P < 0.05). Compared with the SAS and SDS scores at discharge, the scores of parents in the intervention group were significantly lower at 1 month after discharge (P < 0.05), while the scores of parents in the control group were similar at 1 month after discharge (P > 0.05). At discharge, in both the intervention group and the control group, the SAS and SDS scores of the mothers were higher than those of the fathers (P < 0.05). One month after discharge, in the control group, the SAS and SDS scores of the mothers were higher than those of the fathers (P < 0.05). One month after discharge, in the intervention group, the SAS and SDS scores of the mothers were similar to those of the fathers (P > 0.05). The comparison of the SAS and SDS scores of parents with different education levels showed that in both the intervention group and control group, the lower the parents’ educational levels, the higher their SAS and SDS scores (P < 0.05). One month after discharge, in the control group, the lower the parents’ education levels, the higher their SAS and SDS scores (P < 0.05). One month after discharge, in the intervention group, the SAS and SDS scores were similar among parents with different educational levels. The results of the World Health Organization Quality of Life Brief scale showed that the scores of the physiological, psychological, social and environmental fields at 1 month after discharge in the intervention group were significantly higher than those in the control group (P < 0.05).

Conclusion

Providing health education and medical support to the parents of infants with CHD surgery after discharge via telemedicine can effectively relieve parents’ anxiety and depression and improve their quality of life.