bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Enzyme Activities in Pineapple Fruit and Pineapple Waste to Be Applied as Poultry Supplement
Authors: Ridzuan N A M , Shaarani S M , Arshad Z I M , Masngut N , Zainol N , Shariffuddin J H
Published: December 2020

Pineapple fruit contains essential minerals and vitamins with some medicinal values. Hence, it can be used as a raw material to make poultry supplements. Abundance of pineapple waste also has led to the environmental problems such as producing bad odor and has increased waste capacity in the landfill. In this present work, the potential of pineapple fruit and pineapple waste were investigated to be used as the raw materials for poultry supplement based on their enzyme activities. In this study, the effect of fermentation time and type of pineapple substrates on enzyme activities which were xylanase, total cellulase and protease were studied. Two types of pineapple samples have been used in this study which were pineapple fruit and pineapple waste. Four type of pineapple substrates have been prepared which were pineapple juice, pineapple waste, pineapple juice + probiotic and pineapple waste + probiotic. The purpose of adding probiotic in this study was to enhance the fermentation reaction. The results showed that the fermentation time that have the highest enzyme activities for xylanase, total cellulase and protease were observed at day 2, 4 and 6 respectively, where substrate contains pineapple juice + probiotic recorded the highest enzyme activities value for all the three enzymes. This study had investigated that pineapple fruit and pineapple waste contain digestion enzymes which were xylanase, protease and cellulase that can be applied as poultry supplements.
Recent trends of extremophiles application in Microbial Electrochemical Systems as Energy scavenger: A mini review
Authors: Rana S , Mishra P , Krishnan S , Wahid Z A , Sakinah M , Singh L
Published: December 2020

Application of electroactive extremophiles as a biocatalytic agent inside microbial electrochemical systems (MES) holds promises for worldwide practical implementation with improved/enhanced performance under extreme environmental conditions. The MES are microbe catalysed electrochemical platforms that can turn the chemical energy stored inside organic resources/wastewater into electrical energy or other valuable bioelectrofuels with/or without an external electrical stimuli to achieve maximal oxidation of organics (by exoelectrogens) at anode and to extracellularly donating the released electrons to cathode to available electron acceptors like CO2 (by electrotrophs) to further metabolize into bioelectrofuels / or chemical compounds. The functional versatility and diverse applicability of extremophiles is due to their ability to successfully utilize various organic sources even under extreme environmental conditions. Till date, numerous efforts have been made to unravel the hidden potential of microbes in MES operating at standard environmental conditions, but its operability at extreme conditions are often overlooked. The hidden potential of extremophilic microorganisms can be channelized in MES (which either extracted from natural extreme ecosystems or cultivated in fabricated extreme biosystems) to open unknown avenues by producing novel products. This review discusses the recent state of art of extremophilic microbes by exploring novel possibilities for its application as a catalyst in MES.
Carbonization of excess sewage sludge using superheated water vapor to produce fuel
Authors: Haridan N A , Yoshida H , Salleh M A M , Izhar S
Published: December 2020

Excess sewage from activated sludge treatment of municipal wastewater is considered one of the most severe solid waste problems. The excess sewage sludge with 64% moisture content was converted to valuable material throughout the superheated water vapor carbonization process. The superheated water vapor carbonized the excess sewage sludge using a bench-scale Rotary Kiln setup to make fuel at 200°C, 250°C, 300°C, 350°C and 400°C. The effect of carbonization with superheated water vapor on the yield and heating value of fuel was studied. In 1 h treatment, organic waste lost about 70% of its original weight due to volatile release during carbonization. The yield of carbonization decreased when the temperature of carbonization increased. A carbon, hydrogen, nitrogen, and sulfur (CHNS) analyzer was used to measure the elemental composition of the carbonized product. The heating value (LHV) of the fuel carbonized at 250°C was 15.0 MJ/kg, determined by a bomb calorimeter. Thus, this study has shown that instead of the landfill, excess sewage sludge can be utilized using superheated water vapor for conversion to fuel.
Prediction of greenhouse gas emissions resulting from medical waste collection and transport in the city of Kocaeli
Authors: Yaman C , Yaman A B
Published: December 2020

This study investigates future medical waste generation and greenhouse gas emissions resulting from medical waste collection and transportation activities in the city of Kocaeli, Turkey, between the years of 2020 and 2040. Population predictions were carried out by using Ilbank method, arithmetic method and United Nations Development (UNDP) method. Then, medical waste amounts were calculated based on the predicted populations. Among the three methods, arithmetic method was seemed to reflect the most reliable prediction. GHG emissions were calculated based on the fuel consumed by medical waste collection vehicles. The targeted GHGs were CH4 and CO2. Results of this work showed that the total medical waste generated per year was predicted to increase from 2,978 tons in 2020 to 5,203 tons in 2040. Finally, it was determined in this study that medical waste collection and transport would generate a total GHG emission of 11,229-ton CO2-e from 2020 to 2040. Furthermore, average global warming factor (GWF) was calculated as 0.00013 tCO2-e per ton of medical waste collected and transported. This study showed that medical waste collection and transportation generates significant amounts of GHG emissions. Results of this study will guide the local authorities when they plan to replace diesel fuel with alternative fuel types.
Elucidating the non-linear effect of process parameters on hydrogen production by catalytic methane reforming: an artificial intelligence approach
Authors: Alsaffar M A , Mageed A K , Abdel Ghany M A R , Ayodele B V , Mustapa S I
Published: December 2020

This study focuses on the non-linear effect of gas hourly space velocity (GHSV), oxygen (O2) concentration in the feed, the reaction temperature, and the CH4/CO2ratio on hydrogen production by catalytic methane dry reforming using artificial neural networks (ANN). Ten different ANN models were configured by varying the hidden neurons from 1 to 10. The various ANN model architecture was tested using 30 datasets. The ANN model with the topology of 4-9-2 resulted in the best performance with the sum of square error (SSE) of 0.076 and coefficient of determination (R2) greater than 0.9. The predicted hydrogen yield and the CH4conversions by the optimized ANN model were in close agreement with the observed values obtained from the experimental runs. The level of importance analysis revealed that all the parameters significantly influenced the hydrogen yield and the CH4conversion. However, the reaction temperature with the highest level of importance was adjudged the parameter with the highest level of influence on the methane dry reforming. The study demonstrated that ANN is a robust tool that can be employed to investigate predictive modeling and determine the level of importance of parameters on methane dry reforming.
Removal of Anionic Azo Dye from Aqueous Solution Using the Magnetic NiFe2O4 Decorated-Exfoliated Graphite
Authors: Tan L V , Tham N T H , Thinh P V
Published: December 2020

Environmental issues have recently become more prevalent with the rapid development of global industrialization. Organic dyes, a common pollutant, are compounds which are constituted by benzene rings, making them stable and presenting a pollution source that is harmful to human health. In this study, a new nanocomposite adsorbent was fabricated using exfoliated graphite (EG) and NiFe2O4 and evaluated for adsorption capacity against Congo Red (CR) dye. A number of reaction parameters (pH, CR concentration, dosage and contact time) that affect CR adsorption were considered. The successful synthesis of EG@NiFe2O4 was confirmed by FT-IR analysis. Herein, EG@NiFe2O4 and NiFe2O4 adsorbent with dosage of 0.5 g/L were used to removal 100 mL of CR dye at the concentration of 50 ppm. The results showed that adsorption equilibrium was achieved after 120 min for both adsorbents (EG@NiFe2O4 and NiFe2O4). The optimal working pH for adsorption using EG@NiFe2O4 and NiFe2O4 was 6 and 4 respectively. EG@NiFe2O4 could be reused for up to three times without significant loss of adsorption capacity.
Biodegrading evaluation of azo dye group – Congo Red, Methyl Blue and Methyl Orange using bacteria isolated from textile wastewater sediment
Authors: Tran T , Hoa V , Nga N T T , Le D A , Tan L V , Huong L T X , Hong L T A
Published: December 2020

Textile wastewater is one of the most water polluted sources affecting the environment, ecosystems, and causing human malignancy because it contains azo dye pigment group. The treatment requires various types of physical and chemical methods which are time-consuming and hazardous environmental effects. The biodegradable method using microorganisms for textile effluent has been applied due to its environmental friendliness and affordability. Our study aims to identify the microorganisms that are capable of simultaneous degradation of three monochromatic colors belonging to the azo dying group, including Congo Red, Methyl Blue, Methyl Orange via qualitative experiments using Potato Dextrose Agar (PDA) media plus the three monochromatic colors and quantitative experiments using Pt-Co calibration curve to identify the biodegradable efficiency of each and combined bacterial isolated strains. The results showed that six bacterial strains isolated from textile waste sludge were capable of decolorizing the three azo - monochromatic pigments. Moreover, we found that strain Bacillus Subtilis E1 owning Quorum Sensing mode had the highest decoloration efficiency with color removal performance for Methyl Orange, Methyl Blue, and Congo Red was 83.7%, 30.6%, and 94.4%. In particular, the combinations of two Bacillus Subtilis strains yielded a multi-color decolorizing performance with an efficiency of over 80% for each pair.
A Bench Model Design of Gravitational Aeration Tower System as Treatment System for Iron Removal in Groundwater
Authors: Radzi E Z , Wahab M S , Sahdan M Z , Hamdan R , Madun A , Zakariah R A
Published: December 2020

Groundwater is an alternative source of water and is in high demand in Malaysia, particularly in rural areas where hot climate and water scarcity are still challengeable. However, groundwater sources are contaminated by high concentrations of iron in certain regions of Malaysia. In this research work, groundwater samples from tube wells in Kampung Majid Ibrahim, Simpang Renggam were collected and found iron content from 1.9 mg/L to 2.4 mg/L, which exceeds acceptable iron concentration level of 0.3 mg/L. Aeration and filtration methods are commonly employed to remove the iron from groundwater. Despite, there is low water production due to water loss through the air; the aeration process is still economic and efficient. Gravitational Aeration Tower System (GATS) was designed by using SOLIDWORK 2017 and fabricated at bench scale model to mitigate these problems. The GATS was developed with two concepts consisting of aeration from air to water and then from water to air with combination of several processes required for the treatment of water after aeration. Experimental work was conducted at the tube well location and data was collected through AQUAREAD AP2000 and Hanna Iron Checker tools using in-situ test method. The flow rate was set directly through the GATS by the flow of water at 10.0 L/min and by changing the parameters of air. Results demonstrate that dissolved oxygen (DO) levels rises by 86.5% and iron removal increases by 8.03 %. In conclusion, the GATS system is capable of increase the DO levels and decrease iron removal rates with continuous water flow.
Effect of various oil/water emulsion concentration towards PVDF/HMO mixed matrix membrane performance
Authors: Ismail N H , Wan Salleh W N , Ahmad S Z N , Mohd Razali N A , Rosman N , Ismail A F
Published: December 2020

Meeting environmental quality standard for water and freshwater requires the use of innovative technologies, such as membrane technology for treating oily wastewater. Nevertheless, polymeric membrane require modification, as it is incapable of separating or removing oil molecules from oily wastewater. As such, this study incorporated the hydrous manganese dioxide (HMO) with polyvinylidene fluoride (PVDF) to attain mixed matrix membrane (MMM) for separation of various oil/water emulsion concentration feeds (50 ppm, 100 ppm, 500 ppm and 1000 ppm) by using lubricant oil. It was observed that the addition of HMO in MMM had altered the membrane surface morphology, as well as the wetting properties. The presence of HMO in the MMM had increased the membrane hydrophilicity, as it reduced the water contact angle value by up to 40%. Apart from that, the MMM was able to increase the oleophobicity of the membrane by increasing 35% of the oil contact angle value. Both pristine PVDF membrane and PVDF/HMO MMM showed a flux decline with increasing oil/water emulsion concentration but managed to achieve oil rejection percentage greater than 93%.
Parametric Sensitivity Analysis of the Separation Process for N-Butanol Production
Authors: Johan Z J , Tuan Muda T Z , Yee C S
Published: December 2020

n-butanol and iso-butanol are commonly produced by the hydrogenation of n-butyraldehyde and iso-butyraldehyde employing the patented copper catalyst accommodated in the reactors in series. The main cause of the lower n-butanol and iso-butanol yield was due to the catalyst blockage rendering a pressure build-up that could lead to a plant shut down. Bypassing the last reactor from the series could be a potential solution to continue running the plant until the next shutdown plan to replace catalyst. The study adopted simulation approach using Aspen Plus V10 to investigate the effect of bypassing the last reactor in the series to the product purity of the downstream separation processes. The iso-butanol and n-butanol with the desired purity were produced from the distillate and bottom product when the column was operated at the RR of 8.03 and DF of 0.328. The reaction conversion of R-102 was varied from 0.1-0.995 but the variation did not significantly change the composition of the main product. Hence, the present study affirmed that the bypassing of third reactor from the reactor train would not affect the product purity of the main product, n-butanol.
Optimization of green mandarin (Citrus reticulata) essential oil extraction using microwave-assisted hydrodistillation and chemical composition analysis
Authors: Ngo T C Q , Tran T K N , Nguyen V M , Mai H C
Published: December 2020

Citrus reticulataBlanco. peel possess various phytochemical compounds which exhibit high-value biological activities. However, the microwave-assisted technique has not been experimentally adopted in essential oil extraction fromCitrus reticulate. Therefore, the present study attempted adopt this microwave-assisted hydrodistillation method to extract the essential oil from the mandarin fruit peel and improved extraction method specifications. Fresh ground peels were used as the material and underwent three extraction cycles. Technical conditions for optimal oil yield consisted of raw material/solvent ratio of 1: 3 (g/ml), microwave power of 600W, and time extraction of 55 min. After extraction, essential oil products were analyzed for composition on the GC-MS method. Obtained essential oils featured main ingredients including limonene (97.688%), sabinene (0.12%), β-myrcene (1.394%), (-)-β-pinene (0.273%) and 1R-α- pinene (0.525%). These results suggest the use ofCitrus reticulataessential oil in manufacture of antibacterial, antioxidant agents and in cosmetics, food, and pharmaceuticals.
Study on extraction process and analysis of components in essential oils of Vietnamese orange peel (Citrus sinensis) by microwave assisted hydrodistillation extraction
Authors: Toan T Q , Truc T T , Le X T , Quyen N T C , Tran T H
Published: December 2020

This study attempted the extraction of essential oils (EOs) from orange peel, and optimized the experimental parameters of the microwave-assisted hydrodistillation process. Gas chromatography-Mass spectrometry was often used for the assessment of the chemical content of the natural oils collected. Optimal conditions for the extraction process consisted of the ratio of 1:3 peel/water, microwave power of 300W and duration of 45 minutes. These conditions gave the highest yield (2%). From the gas chromatographic results, five components were identified in the obtained orange peel EOs with Limonene being the major components (98.416%). Based on availability, orange peel is suggested as an economically viable source for limonene production. Obtained results are expected to aid in mitigation of environmental impact caused by agricultural wastes.
Evaluate the Chemical Composition of Peels and Juice of Seedless Lemon (Citrus latifolia) Grown in Hau Giang Province, Vietnam
Authors: Pham T , Nguyen N T P , Dinh D V , Kieu N Th , Bach L G , Phong H X , Muoi N V , Truc T T
Published: December 2020

In this study, the specific chemical composition of Seedless Lemon (Citrus latifolia) grown in Hau Giang Province, Vietnam was determined. The experiment was conducted based on the baseline methods referenced from previous studies. The results of the component survey show that, in Persian Lime, the acidity is 0.637 ± 0.08 g/L and 4.916 ± 0.03 g/L respectively with lemon peel and lemon juice (pH is 4.5 and 2 respectively). The basic components are also determined with the parameters corresponding to lemon peel and lemon juice including: Brix 2% and 8%, ash 1,780 ± 0.004% and 0.314 ± 0.002%, lipid content 2.93 ± 0.044% and 0.542 ± 0.051%. In which, the content of vitamin C in lemon juice is quite good, reaching 8.392 ± 0.28 mg/g. This research helps shape the basic parameters of local Vietnamese raw materials, thereby laying the premise for the development of related products.
Comparative study of Mandarin (Citrus reticulata Blanco) essential oil extracted by microwave-assisted hydrodistillation, microwave extraction and hydrodistillation methods from Tien Giang, Vietnam
Authors: Dao T P , Ngo T C Q , Le T D , Ngo H D , Thao Phuong , Tran T G , Nguyen N T , Huynh X P
Published: December 2020

The mandarin (Citrus reticulata Blanco) essential oil is well-known for bactericidal, antioxidant and anti-cancer properties. Thus, an effective extraction method is required to obtain high oil yield with an abundant content of bioactive compounds. In the present study, the chemical profiles of essential oils extracted from the peels of Mandarin) via hydrodistillation (HD), microwave-assisted hydrodistillation (MAHD) and microwave extraction (ME) were reported in this study. Extraction techniques were carried out at their optimal conditions and the results were compared with each other. Gas chromatography-mass spectrometry (GC-MS) was employed to perform compositional determination. A total of 5 components was determined, accounting for almost 100% of total oil content. The extraction efficiencies were 3.6%, 6.8%, and 5.5% respectively obtained from HD, MAHD and ME. The results showed that MAHD seemed to result in higher yield and essential oil with identical chemical composition and quality in comparison with those of other methods, suggesting that MAHD was a potential alternative method to HD to reduce the time and cost of the extraction process.
Studies on Polyphenol content, flavonoid content, and antioxidant activity of Graviola tea pulp (Annona muricata L.)
Authors: Tran Q T , Vo T T , Nguyen P T N , Nguyen N Q , Tran T Y N
Published: December 2020

Tea is the most commonly consumed beverage worldwide due to promote health and prevention of some human diseases. Soursop tea pulp is well-known for containing a significant content of ascorbic acid (TAA), polyphenols (TPC) and flavonoids (TFC). In the present study, different pulp tea samples with varying dates of production were checked for TAA, TPC, TFC, 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging activities, followed by sensory evaluation. There is a difference in TAA between sample (1) and (4), achieved 7.43 ± 0.04 mg/g DM and 12.21 ± 0.04 mg/g DM, respectively. TFC content ranged between 0.13 and 0.18. The phenolics group in tea is high and there are differences between the 3 recent production samples with (1): 3.81mg QC/g DM fluctuation. In sample 1, the antioxidant activity of the ethanol extract of Soursop was correlated with total phenolic and flavonoid content with values of 0.26 mgAA / g DM, 2.61 mgAA / g DM for DPPH and ABTS scavenging activity, respectively. Moreover, the CIE Lab* color space of the soursop tea is measured in the dark area, the L * difference achieved at 30.82 ± 1.24 (2) lowest and the highest 37.42 ± 4.77 (1). Consumer sensory evaluation is performed with results based on a 5-point scale describing: flavor, aroma, color, and favorite. The results showed sensory acceptance of all four samples and neligible difference in scores.
Dynamic constitutive behavior investigation of a novel low alloy ultra-high strength steel
Authors: Lu Tie , Li Yong , Zhao Hongjin , Wang Chunxu , Han Shun
Published: December 2020

The goal of this work is to reveal the dynamic mechanical properties and constitutive relationship of a novel low alloy ultra-high strength DT506 steel under high strain rates. The quasi-static state and dynamic compression behavior of the material at the strain rates of 10−3–103 s−1 were examined using an MTS landmark electro-hydraulic servo universal tester and a Split-Hopkinson bar (SHPB). The results show that DT506 steel is a strain-rate-sensitive material that shows an increase in strength with increasing strain rate. Based on the quasi-static and dynamic compression data, the parameters in the Cowper-Symonds (C-S) and the Johnson-Cook (J-C) models are determined. Since the previously developed models are cannot accurately predict the effect of the strain rate. A new theoretical model is obtained through the optimization of the parameters in the standard J-C model. The optimized model greatly improves the prediction accuracy of the true stress-strain dynamic behavior of materials. This new model is helpful for the verification of the underlying mechanism of the dynamic behavior of the material. Test results may provide basic data for future research on dynamic mechanical properties and constitutive relationship of metal alloys.
Adsorption of reactive red 2BF onto Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles fabricated via the ethanol solution of nitrate combustion process
Authors: Chen Jianhong , Wang Zhou , Lv Zhixiang
Published: December 2020

An ethanol solution of nitrate combustion process for the fabrication of magnetic Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles was introduced. And the Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles fabricated at 500 °C for 2 h were characterized by means of the transmission electron microscopy (TEM), the vibrating sample magnetometer (VSM), the scanning electron microscopy (SEM), and the x-ray diffraction (XRD). The magnetic Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles were useful to remove reactive red 2BF (RR-2BF) from wastewater, and the adsorption mechanism of RR-2BF onto magnetic Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles was explored. The experimental results revealed that Temkin isotherm model and the pseudo-second kinetics model matched well with adsorption process, which indicated that there was monolayer and multilayer adsorption in the adsorption behavior of RR-2BF onto magnetic Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles. While, the effects of the adsorbent dosage and pH value of solution on the adsorption process were investigated, and it was found that with the increase of them, the adsorbances of RR-2BF onto Ni0.3Co0.2Zn0.5Fe2O4 nanoparticles decreased. The maximum adsorption capacity of Ni0.3Co0.2Zn0.5Fe2O4 was about 138 mg g−1, and the adsorbance amounted to 75% of the initial one after 8 recycles.
Materials selection method using TOPSIS with some popular normalization methods
Authors: Yang Won-Chol , Chon Son-Hak , Choe Chol-Min , Yang Ji-Yon
Published: December 2020

The aim of this paper is to propose the methods to select reasonable normalization method in TOPSIS and decide best optimal material combined with individual results from TOPSIS with some popular normalization methods. In this paper, to evaluate performance of normalization method, entropy-based and variation coefficient-based performance scores are introduced. To decide final result of materials selection combined with individual results from TOPSIS with different normalization methods, final rank index of alternative material is proposed. To verify the effectiveness of the proposed methods, TOPSIS with some popular normalization methods is applied to select optimal tribological coating material. As a result, it is desirable to select the normalization method with highest entropy-based and variation coefficient-based performance scores. In order to select best optimal material using TOPSIS with some popular normalization methods, the method to decide final result of materials selection is proposed by using final indices of alternative materials. The proposed methods may be widely used to solve the materials selection problems in engineering practice.
Improved performance of InGaN/GaN Near-UV light-emitting diodes with staircase hole injector
Authors: Kim Sang-Jo , Kim Seongjun , Oh Semi , Lee Kwang Jae , Cho Chu-Young , Ro Han-Sol , Kang Min-Jae , Sung Minje , Lee Nam-Suk , Shin Hoon-Kyu
Published: December 2020

We report the enhanced performance of near-ultraviolet (NUV) InGaN/GaN multiple quantum-well (MQW) light-emitting diodes (LEDs) with a staircase hole injector (SHI). Simulation results indicate that the internal electrostatic field in the QW of the LED-SHI is decreased owing to the reduced sheet charge density at the interface between QW and quantum barrier (QB) caused by the smaller In content difference. Additionally, the SHI structure in the QBs suppresses the ballistic or quasi-ballistic hole transport, thus enhancing efficient hole injection into the QWs. The radiative output power of an LED-SHI is increased by 25.3% at 300 mA over that of conventional LEDs with GaN QBs. The droop of internal quantum efficiency (IQE) an LED-SHI at 300 A·cm−1 is 6.1%, while the LED with GaN QBs has an IQE droop of 17.7%. The reduced IQE droop and increased radiative output power in the LED-SHI is attributed to the reduced hole overflow, increased hole injection into the MQW and the decreased electrostatic field in the MQWs. The results show that the SHI structure in the LED is promising for improved performance in high-power GaN-based NUV LEDs.
Personalized information diffusion in signed social networks
Authors: Qu Cunquan , Bi Jialin , Wang Guanghui
Published: December 2020

Understanding the dynamics in complex networks is crucial in various applications, such as quelling the epidemic outbreak, preventing the spread of rumors online, and promoting the diffusion of science and technology information. In this study, we investigated a personalized information diffusion (PID) mechanism on signed networks. The main assumption of this mechanism is that if a message is good for the stakeholder, then it is also good for his/her friends but bad for his/her enemies. At each step, the individual who receives the information will determine whether to forward it based on his/her relationship with the stakeholder. We find that bad news may spread further than good news even if a stakeholder has more directly connected friends than enemies. Moreover, the nodes that have more (potential) friends across the network can spread good information more widely. However, individuals who have more enemies locally can spread bad information more widely. Our findings may inspire the design of strategies for controlling information, epidemics, or rumors in social networks.
Evaluation of biological and economic efficiency of the All Heifer, No Cow beef production system using a system dynamics model based on 6 yr of demonstration herd data
Authors: Harrison Meredith A , Sheehan John J , Seidel George E , Mooney Dan F , Rhoades Ryan D , Ahola Jason K
Published: December 2020

Alternative management strategies with no cows and all heifers may improve biological and economic efficiency of beef production. The All Heifer, No Cow (AHNC) beef production system involves insemination of nulliparous heifers with female sex-selected semen (FSS) to produce primarily female calves that are early weaned at 3 mo of age. Dams are finished on a high concentrate diet and harvested before 30 mo of age. The objectives of this research were to: 1) build a dynamic model of an AHNC beef production system to quantify system biological and economic efficiency; 2) compare effects of utilizing FSS vs. conventional semen on biological and economic efficiency; 3) evaluate what-if scenarios to determine the effects on biological and economic efficiency of changing variables ±5%, 10%, 15%, and 20% from initial observed values; and 4) evaluate the effects on biological and economic efficiency of changing variables ±10% from initial observed values. A model was built over a 21-yr horizon using Stella Architect. Biological parameter values in the model were based on the 6 yr of data collected from the management of an AHNC demonstration herd. In the model animal, total digestible nutrients (TDN) intake, hot carcass weight (HCW), and age at harvest were randomized. Feed, animal, and carcass prices included in the model were based on 10 yr of historical U.S. price data. Key response variables were biological and economic efficiency (mean ± SD). Biological efficiency was defined as the ratio of output (kilograms of HCW produced) to input (lifetime kilograms of feed TDN consumed), and economic efficiency was measured using a benefit–cost ratio (BCR) and unit variable cost (UVC). Over 40 simulation runs, the predicted mean biological efficiency was 0.0714 ± 0.0008. Economic efficiency was 0.95 ± 0.02 and US $445.41 ± 0.06 for BCR and UVC, respectively. Biological and economic efficiency was improved in the conventional semen scenario; biological efficiency was 0.0738 ± 0.0008, and BCR and UVC were 0.99 ± 0.04 and US $407.24 ± 0.006, respectively. Under this parameterization and market conditions, the AHNC beef production system failed to achieve profitability under any scenario that was evaluated. However, this review did not account for the potential increased genetic benefit from a decreased generation interval and the reduction in feed energy in comparison to a conventional cow/calf system.
Navigating Institutions for Integration: Perceived Institutional Barriers of Access to the Labour Market among Refugee Women in Sweden
Authors: Spehar Andrea
Published: December 2020

Sweden may in many respects be regarded as one of the most gender-equal countries in the world today. However, when looking at the situation of immigrant women a more unsettling picture emerges. Employment rates illustrate large gaps between native and immigrant women, as well as significant gender gaps between immigrant men and women. When investigating plausible explanations for underrepresentation of immigrant women in the labour market, scholars have mainly focussed on cultural and individual explanatory factors. In contrast, this article casts our analytical gaze towards institutional factors by examining the experiences of refugee women who, despite expressing a positive attitude and strong willingness to establish themselves on the Swedish labour market, had not succeeded in finding secure employment. Drawing upon in-depth interviews with refugee women, the results suggest that the insufficient institutional support during the first years in Sweden, devaluation of competence and challenges with ‘starting over’ are perceived as central barriers hindering their access to the Swedish labour market. To facilitate higher labour force participation among refugee women in Sweden it is crucial to develop and implement gender-sensitive measures that target different groups of immigrant women and meet their distinct experiences, needs, and interests.
High resolution X-ray spectroscopy of Supergiant HMXB 4U1700−37 during the compact object eclipse.
Authors: Martínez-Chicharro M , Grinberg V , Torrejón J M , Schulz N , Oskinova L , Nowak M , Fürst F , Hell N , Hainich R
Published: December 2020

We present an analysis of the first observation of the iconic High Mass X-ray Binary 4U 1700−37 with the Chandra High Energy Transmission Gratings during an X-ray eclipse. The goal of the observation was to study the structure/physical conditions in the clumpy stellar wind through high resolution spectroscopy. We find that: a) emission line brightness from K shell transitions, corresponding to near neutral species, directly correlates with continuum illumination. However, these lines do not greatly diminish during eclipse. This is readily explained if fluorescence Kα emission comes from the bulk of the wind. b) The highly ionised Fe xxv and Fe xxvi Lyα diminish during eclipse. Thus, they must be produced in the vicinity of the compact object where log ξ > 3. c) to describe the emission line spectrum, the sum of two self consistent photo ionisation models with low ionisation (log ξ ∼ −1) and high ionisation (log ξ ∼ 2.4) is required. From their emission measures, the clump-to-interclump density ratio can be estimated to be nc/ni ∼ 300. To fit the complex He-like Si xiii profile, the plasma requires a broadening with vbulk ∼ 840 km s−1. Reproducing the observed r ≈ f line fluxes requires the addition of a third collisionally ionised plasma. d) Emission lines widths appear unresolved at the hetg gratings resolution with exception of Silicon. There is no clear radial segregation between (quasi)neutral and ionised species, consistent with cold wind clumps interspersed in a hot rarefied interclump medium.
The MRN complex promotes DNA repair by homologous recombination and restrains antigenic variation in African trypanosomes
Authors: Mehnert Ann-Kathrin , Prorocic Marco , Dujeancourt-Henry Annick , Hutchinson Sebastian , McCulloch Richard , Glover Lucy
Published: December 2020

Homologous recombination dominates as the major form of DNA repair in Trypanosoma brucei, and is especially important for recombination of the subtelomeric variant surface glycoprotein during antigenic variation. RAD50, a component of the MRN complex (MRE11, RAD50, NBS1), is central to homologous recombination through facilitating resection and governing the DNA damage response. The function of RAD50 in trypanosomes is untested. Here we report that RAD50 and MRE11 are required for RAD51-dependent homologous recombination and phosphorylation of histone H2A following a DNA double strand break (DSB), but neither MRE11 nor RAD50 substantially influence DSB resection at a chromosome-internal locus. In addition, we reveal intrinsic separation-of-function between T. brucei RAD50 and MRE11, with only RAD50 suppressing DSB repair using donors with short stretches of homology at a subtelomeric locus, and only MRE11 directing DSB resection at the same locus. Finally, we show that loss of either MRE11 or RAD50 causes a greater diversity of expressed VSG variants following DSB repair. We conclude that MRN promotes stringent homologous recombination at subtelomeric loci and restrains antigenic variation.
Extra-virgin olive oil and the gut-brain axis: influence on gut microbiota, mucosal immunity, and cardiometabolic and cognitive health
Authors: Millman Jasmine F , Okamoto Shiki , Teruya Taiki , Uema Tsugumi , Ikematsu Shinya , Shimabukuro Michio , Masuzaki Hiroaki
Published: December 2020

Extra-virgin olive oil (EVOO), a popular functional food and major source of fat in the Mediterranean diet, possesses a variety of healthful components, including monounsaturated fatty acids and bioactive phenolic compounds that, individually and collectively, exert beneficial effects on cardiometabolic markers of health and act as neuroprotective agents through their anti-inflammatory and antioxidant activities. The gut microbiota and health of the intestinal environment are now considered important factors in the development of obesity, metabolic disease, and even certain neurodegenerative conditions via the gut-brain axis. Recently, data are emerging which demonstrate that the health-promoting benefits of EVOO may also extend to the gut microbiota. In this review, we aimed to examine findings from recent studies regarding the impact of EVOO on gut microbiota and intestinal health and explore how modulations in composition of gut microbiota, production of microbially produced products, and activity and functioning of the mucosal immune system may lead to favorable outcomes in cardiovascular, metabolic, and cognitive health.
Rehabilitation Intensity and Patient Outcomes in Skilled Nursing Facilities in the United States: A Systematic Review
Authors: Prusynski Rachel A , Gustavson Allison M , Shrivastav Siddhi R , Mroz Tracy M
Published: December 2020

Objective

Exponential increases in rehabilitation intensity in skilled nursing facilities (SNFs) motivated recent changes in Medicare reimbursement policies, which remove financial incentives for providing more minutes of physical therapy, occupational therapy, and speech therapy. Yet, there is concern that SNFs will reduce therapy provision and patients will experience worse outcomes. The purpose of this systematic review was to synthesize current evidence on the relationship between therapy intensity and patient outcomes in SNFs.

Methods

PubMed, Medline, Scopus, Embase, CINAHL, PEDro, and COCHRANE databases were searched. English-language studies published in the United States between 1998 and February 14, 2020, examining the relationship between therapy intensity and community discharge, hospital readmission, length of stay (LOS), and functional improvement for short-stay SNF patients were considered. Data extraction and risk of bias were performed using the American Academy of Neurology Classification of Evidence scale for causation questions. American Academy of Neurology criteria were used to assess confidence in the evidence for each outcome.

Results

Eight observational studies met inclusion criteria. There was moderate evidence that higher intensity therapy was associated with higher rates of community discharge and shorter LOS. One study provided very low-level evidence of associations between higher intensity therapy and lower hospital readmissions after total hip and knee replacement. There was low-level evidence indicating higher intensity therapy is associated with improvements in function.

Conclusions

This systematic review concludes with moderate confidence that higher intensity therapy in SNFs leads to higher community discharge rates and shorter LOS. Future research should improve quality of evidence on functional improvement and hospital readmissions.

Impact

This systematic review demonstrates that patients in SNFs may benefit from higher intensity therapy. Because new policies no longer incentivize intensive therapy, patient outcomes should be closely monitored to ensure patients in SNFs receive high-quality care.
Does Switching Antipsychotics Ameliorate Weight Gain in Patients With Severe Mental Illness? A Systematic Review and Meta-analysis
Authors: Siskind Dan , Gallagher Erin , Winckel Karl , Hollingworth Samantha , Kisely Steve , Firth Joseph , Correll Christoph U , Marteene Wade
Published: December 2020

Objective

Obesity and adverse metabolic outcomes in patients with severe mental illness are clinically significant but potentially preventable. Importantly, the evidence for switching to antipsychotics to reduce cardiometabolic burden is unclear.

Method

PubMED, Embase, PsycINFO, and Cochrane were searched from inception to March 8, 2020. Articles reporting weight and metabolic changes after antipsychotic switching vs staying on the previous antipsychotic were meta-analyzed both across and within group.

Results

Of 61 identified studies, 59 were meta-analyzed (40% rated high quality). In the switch-vs-stay pairwise meta-analyses, only aripiprazole significantly reduced weight (−5.52 kg, 95% CI −10.63, −0.42, P = .03), while olanzapine significantly increased weight (2.46 kg, 95% CI 0.34, 4.57, P = .02). Switching to aripiprazole also significantly improved fasting glucose (−3.99 mg/dl, 95% CI −7.34, −0.64, P = .02) and triglycerides (−31.03 mg/dl, 95% CI −48.73, −13.34, P = .0001). Dropout and psychosis ratings did not differ between switch and stay groups for aripiprazole and olanzapine. In before-to-after switch meta-analyses, aripiprazole (−1.96 kg, 95% CI −3.07, −0.85, P < .001) and ziprasidone (−2.22 kg, 95% CI −3.84, −0.60, P = .007) were associated with weight loss, whereas olanzapine (2.71 kg, 95% CI 1.87, 3.55, P < .001), and clozapine (2.80 kg, 95% CI 0.26, 5.34, P = .03) were associated with weight gain. No significant weight or other cardiometabolic changes were observed when switching to amisulpride, paliperidone/risperidone, quetiapine, or lurasidone.

Conclusions

Switching antipsychotics to agents with lower weight gain potential, notably to aripiprazole and ziprasidone, can improve weight profile and other cardiometabolic outcomes. When choosing switch agents, both the weight gain potential of the pre- and post-switch antipsychotic must be considered. Antipsychotic switching in psychiatrically stable patients must be weighed against the risk of psychiatric worsening.
Genetic Liability for Schizophrenia and Childhood Psychopathology in the General Population
Authors: Hannigan Laurie J , Askeland Ragna Bugge , Ask Helga , Tesli Martin , Corfield Elizabeth , Ayorech Ziada , Helgeland Øyvind , Magnus Per , Njølstad Pål Rasmus , Øyen Anne-Siri , Stoltenberg Camilla , Andreassen Ole A , Davey Smith George , Reichborn-Kjennerud Ted , Havdahl Alexandra
Published: December 2020

Genetic liability for schizophrenia is associated with psychopathology in early life. It is not clear if these associations are time dependent during childhood, nor if they are specific across different forms of psychopathology. Using genotype and questionnaire data on children (N = 15 105) from the Norwegian Mother, Father and Child Cohort Study, we used schizophrenia polygenic risk scores to test developmental stability in associations with measures of emotional and behavioral problems between 18 months and 5 years, and domain specificity in associations with symptoms of depression, anxiety, conduct problems, oppositionality, inattention, and hyperactivity at 8 years. We then sought to identify symptom profiles—across development and domains—associated with schizophrenia polygenic liability. We found evidence for developmental stability in associations between schizophrenia polygenic risk scores and emotional and behavioral problems, with the latter being mediated specifically via the rate of change in symptoms (β slope = 0.032; 95% CI: 0.007–0.057). At age 8, associations were better explained by a model of symptom-specific polygenic effects rather than effects mediated via a general psychopathology factor or by domain-specific factors. Overall, individuals with higher schizophrenia polygenic risk scores were more likely (OR = 1.310 [95% CIs: 1.122–1.528]) to have a profile of increasing behavioral and emotional symptoms in early childhood, followed by elevated symptoms of conduct disorder, oppositionality, hyperactivity, and inattention by age 8. Schizophrenia-associated alleles are linked to specific patterns of early-life psychopathology. The associations are small, but findings of this nature can help us better understand the developmental emergence of schizophrenia.
IL-6 Predicts Poor Early Post-Natal Growth in Very Low-Birth-Weight Infants in a Low-Middle Income Setting
Authors: Mackay Cheryl Anne , Smit James Stephanus , Khan Farhaad , Dessai Fazana , Masekela Refiloe
Published: December 2020

Background

Extra-uterine growth restriction (EUGR) is common in preterms and may be associated with elevated pro-inflammatory cytokines.

Objective

Describe postnatal growth in a cohort of very low-birth-weight (VLBW) infants and determine the association of interleukin-6 (IL-6) and tumour necrosis factor alpha (TNF-α) in umbilical cord blood with growth at 40 weeks and 12 months postmenstrual age (PMA).

Methods

Single-centre, prospective cohort study conducted from 1 June 2017 to 31 January 2019 with follow-up to 31 March 2020. Infants <1500 g at birth were enrolled, cord blood collected for IL-6 and TNF-α assays and postnatal care, including anthropometry, provided to 12 months PMA. Informed consent and ethics approval were obtained.

Results

In total, 279 patients were enrolled; 84 (30.1%) died before 12 months and 91 (32.6%) lost to follow-up. Anthropometry was available for 151 infants at 40 weeks and 105 at 12 months. Z-Scores at 40 weeks for males and females combined were −2.5, −2.1 and −1.2 for weight, length and head circumference. EUGR occurred in 103/113 (91.2%), 98/107 (91.6%) and 70/109 (64.2%) participants for weight, length and head circumference. Elevated IL-6 was associated with restricted weight (56.0 vs. 14.5 pg/ml, p = 0.02) and length (60.4 vs. 7.3 pg/ml, p = 0.01) at 40 weeks. There was no difference in IL-6 at 12 months and no difference in TNF-α at 40 weeks or 12 months.

Conclusion

The study reports significant EUGR. Elevated IL-6 was associated with growth restriction at 40 weeks but not 12 months PMA.
Witches’ Broom Disease of Lime Contributes to Phytoplasma Epidemics and Attracts Insect Vectors
Authors: Al-Subhi A. M. , Al-Sadi A. M. , Al-Yahyai R. A. , Chen Y. , Mathers T. , Orlovskis Z. , Moro G. , Mugford S. , Al-Hashmi K. S. , Hogenhout S. A.
Published: December 2020

An insect-transmitted phytoplasma causing Witches’ Broom Disease of Lime (WBDL) is responsible for the drastic decline in lime production in several countries. However, it is unclear how WBDL phytoplasma (WBDLp) induces witches’ broom symptoms and if these symptoms contribute to the spread of phytoplasma. Here we show that the gene encoding SAP11 of WBDLp (SAP11WBDL) is present in all WBDLp isolates collected from diseased trees. SAP11WBDL interacts with acid lime (Citrus aurantifolia) TCP transcription factors, specifically members of the TB1/CYC class that have a role in suppressing axillary branching in plants. Sampling of WBDLp-infected lime trees revealed that WBDLp titers and SAP11WBDL expression levels were higher in symptomatic leaves compared with asymptomatic sections of the same trees. Moreover, the witches’ brooms were found to attract the vector leafhopper. Defense genes that have a role in plant defense responses to bacteria and insects are more downregulated in witches’ brooms compared with asymptomatic sections of trees. These findings suggest that witches’ broom-affected parts of the trees contribute to WBDL epidemics by supporting higher phytoplasma titers and attracting insect vectors.