bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effectiveness of Conservation Crop Rotation for Water Pollutant Reduction from Agricultural Areas
Authors: Koropeckyj-Cox Lydia , Christianson Reid D. , Yuan Yongping 
Published: April 2021

HighlightsAdjusting nitrogen (N) fertilization rates for corn following legumes can reduce N losses.Including perennial legumes in corn rotations can reduce nitrate-N losses and improve water quality.Crop rotations that include three or more years of legumes can be cost-effective.Corn-soybean was the most cost-effective, with a net benefit in nitrate-N loss reduction compared to continuous corn.Abstract. Legumes included in corn-based crop rotation systems provide a variety of benefits to the subsequent crops and potentially to the environment. This review aims to synthesize available data from the literature on legume N credits and the effects of crop rotations on water quality, as well as to analyze the cost benefits associated with different legume-corn rotation systems. We found that there was much variation in reported values for legume N credits to subsequent corn crops, from both empirical results and recommendations made by U.S. land grant universities. But despite inherent complexity, accounting for this contribution is critical when estimating optimal N fertilizer application rates as part of nutrient management. Results from research on the influence of crop rotations on water quality show that including legumes in corn-based rotation systems generally decreases nitrate-N concentrations in subsurface drainage discharge. Our cost analysis showed that incorporating legumes in cropping systems reduced N fertilizer and pesticide costs compared to conventional cropping systems, i.e., continuous corn and corn-soybean rotations, but extended rotations, such as corn-soybean-alfalfa-alfalfa-alfalfa, are not as profitable as conventional systems in the U.S. Midwest. In comparing continuous corn and corn-soybean rotations, although their impacts on water quality are not significantly different when using overall means from the literature data, corn-soybean rotations are more profitable than continuous corn. When using data from papers that directly compared the two, we found that switching from continuous corn to corn-soybean can provide a benefit of $5 per kg N loss reduction. The cost analysis methods used could be tailored to any location or management scenario with appropriate inputs and serve as a useful tool for assessing cost benefits for other agricultural conservation practices. Legume-corn crop rotations have the potential to be an effective conservation practice with the ultimate goal of improving water quality, and, with further research, these rotations could be made even more effective by integrating them into a multi-practice system. Keywords: Conservation practice, Cost analysis, Crop rotation, Nitrate, Nutrient management, Water quality.
Experimental Study on Critical Shear Stress of Cohesive Soils and Soil Mixtures
Authors: Gao Xiaojing , Wang Qiusheng , Xu Chongbang , Su Ruilin 
Published: April 2021

HighlightsErosion tests were performed to study the critical shear stress of cohesive soils and soil mixtures.Linear relationships were observed between critical shear stress and cohesion of cohesive soils.Mixture critical shear stress relates to noncohesive particle size and cohesive soil erodibility.A formula for calculating the critical shear stress of soil mixtures is proposed and verified.Abstract. The incipient motion of soil is an important engineering property that impacts reservoir sedimentation, stable channel design, river bed degradation, and dam breach. Due to numerous factors influencing the erodibility parameters, the study of critical shear stress (tc) of cohesive soils and soil mixtures is still far from mature. In this study, erosion experiments were conducted to investigate the influence of soil properties on the tc of remolded cohesive soils and cohesive and noncohesive soil mixtures with mud contents varying from 0% to 100% using an erosion function apparatus (EFA). For cohesive soils, direct linear relationships were observed between tc and cohesion (c). The critical shear stress for soil mixture (tcm) erosion increased monotonically with an increase in mud content (pm). The median diameter of noncohesive soil (Ds), the void ratio (e), and the organic content of cohesive soil also influenced tcm. A formula for calculating tcm considering the effect of pm and the tc of noncohesive soil and pure mud was developed. The proposed formula was validated using experimental data from the present and previous research, and it can reproduce the variation of tcm for reconstituted soil mixtures. To use the proposed formula to predict the tcm for artificial engineering problems, experimental erosion tests should be performed. Future research should further test the proposed formula based on additional experimental data. Keywords: Cohesive and noncohesive soil mixture, Critical shear stress, Erodibility, Mud content, Soil property.
Development of a Robotic Harvesting Mechanism for Button Mushrooms
Authors: Huang Mingsen , Jiang Xiaohu , He Long , Choi Daeun , Pecchia John , Li Yaoming 
Published: April 2021

HighlightsA robotic mushroom picking mechanism was developed, including positioning, picking, and stipe trimming.The picking end-effector was designed based on a bending motion around the stipe-substrate joint.The overall success rate of the developed picking mechanism reached 91.4%.Acting time and air pressure for the suction cup were studied in mushroom bruise level tests.Abstract. Button mushroom (Agaricus bisporus) harvesting mainly relies on costly manpower, which is time-consuming and labor-intensive. Robotic harvesting is an alternative method to address this challenge. In this study, a robotic mushroom picking mechanism was designed, including a picking end-effector based on a bending motion, a four degree-of-freedom (DoF) positioning end-effector for moving the picking end-effector, a mushroom stipe trimming end-effector, and an electro-pneumatic control system. A laboratory-scale prototype was fabricated to validate the performance of the mechanism. Bruise tests on the mushroom caps were also conducted to analyze the influence of air pressure and acting time of the suction cup on bruise level. The test results showed that the picking end-effector was successfully positioned to the target locations. The success rate of the picking end-effector was 90% at first pick and increased to 94.2% after second pick. The main reason for the failures was inclined growing condition of those mushrooms, resulting in difficulties in engaging the mushroom cap with the suction cup facing straight downward. The trimming end-effector achieved a success rate of 97% overall. The bruise tests indicated that the air pressure was the main factor affecting the bruise level, compared to the suction cup acting time, and an optimized suction cup may help to alleviate the bruise damage. The laboratory test results indicated that the developed picking mechanism has potential to be implemented in automatic mushroom harvesting. Keywords: Bruise test, End-effector, Mushroom, Robotic harvesting.
Design and Testing of a Shearing and Breaking Device for Mulch Film and Cotton Stalk Mixtures
Authors: Pan Feng , Hu Bin , Luo Xin , Guo Mengyu , He Haomeng 
Published: April 2021

HighlightsThis article presents a shearing and breaking device for mulch film and stalk mixtures after mechanized recovery.The focus is on a curved V-shaped mechanism with three-dimensional precompression and shearing functions.The device can efficiently and continuously perform film crushing, stalk crushing, and entanglement breaking.The crushed film and stalk mixture is conducive to material separation, further treatment, and recycling.Abstract. Because the mixture of mulch film and stalks collected in harvested cotton fields in Xinjiang, China, cannot be separated mechanically, a technical solution for shearing and breaking is proposed. This study designed a shearing and breaking device for film and stalk mixtures that can continuously perform film crushing, stalk crushing, and entanglement breaking. The design focuses on a curved V-shaped shearing mechanism, which provides three-dimensional shearing and improves the crushing of film and stalks. The linear speed of the conveying rollers (x1), the working angle of the shearer (x2), and the speed of the shearer spindle (x3) were selected as influencing factors, and the crushed film rate (Ph), crushed stalk rate (Gh), and broken entanglement rate (Kh) were used as evaluation indexes in quadratic orthogonal rotation combination tests. The test results were analyzed with Design-Expert software, and a regression model between each factor and the evaluation indexes was established to analyze the significance of each factor’s influence. The results showed that the influences of the three factors on Ph in descending order were x3, x2, and x1. The order of influence on Gh and Kh was x3, x1, and x2. The optimization module in the software was used for parameter optimization, and the optimal combination of working parameters of the device was x1 = 0.98 m s-1, x2 = 153°, and x3 = 753 r min-1. The optimized parameter combination was tested and verified, and the results were Ph = 77.28%, Gh = 87.78%, and Kh = 85.30%. The test results are basically consistent with the predicted values, and the optimized working parameters are reliable and can meet the requirements for the shear fracture of film and stalk mixtures. This research provides a technical reference for the cutting and crushing of complex mixed solid materials. Keywords: Agricultural machinery, Curved V-shaped moving knife, Design, Film and stalk mixture, Parameter optimization.
Evolution of Phosphine from Aluminum Phosphide Pellets
Authors: Elsayed Sherif , Casada Mark E. , Maghirang Ronaldo G. , Wei Mingjun 
Published: April 2021

HighlightsThis study developed a mathematical relationship accounting for the production rate of phosphine.The effect of temperature on phosphine sorption into wheat is described mathematically.A computational fluid dynamics (CFD) model was built to predict the phosphine concentration in fumigated grain.Experiments were conducted to validate the CFD model.Abstract. Phosphine gas (PH3) is widely used as a fumigant for stored product insect infestations due to its relatively low price and the near absence of residual chemical on the grain. Understanding the behavior of phosphine gas inside the fumigated space is crucial to maintaining a lethal dosage and protecting stored grain from subsequent insect damage. Phosphine is available either in gas form or is produced from a solid material, as pellets or tablets, that reacts with water in the air. The solid form is the most commonly used; however, limited information is available on the rate of phosphine gas generated from the solid material. In this study, a mathematical equation was formulated, based on previous studies in the literature, to describe the gas generation rate. This equation was incorporated into a computational model using ANSYS Fluent 19.1, a commercial software for computational fluid dynamics (CFD) analysis. The computational model developed here allows prediction of the phosphine concentration within a fumigated grain bulk. The PH3 sorption was included in the model. The effect of temperature on the sorption rate was investigated based on published data, and the rate change due to temperature was characterized. The gas generated by a single pellet was measured in laboratory experiments in a 0.208 m3 sealed barrel. The measurements confirmed the CFD results with an error of 0.3%, 0.9%, and 7.2% for three different configurations. The deviations seen between the experimental replicates increased the error and show the need for further investigation of the effects of temperature, grain age and history, leakage, and other factors. Keywords: CFD, Evolution rate, Phosphine, Sorption.
Design framework for metasurface optics-based convolutional neural networks
Authors: Burgos Carlos Mauricio Villegas , Yang Tianqi , Zhu Yuhao , Vamivakas A. Nickolas 
Published: April 2021

Deep learning using convolutional neural networks (CNNs) has been shown to significantly outperform many conventional vision algorithms. Despite efforts to increase the CNN efficiency both algorithmically and with specialized hardware, deep learning remains difficult to deploy in resource-constrained environments. In this paper, we propose an end-to-end framework to explore how to optically compute the CNNs in free-space, much like a computational camera. Compared to existing free-space optics-based approaches that are limited to processing single-channel (i.e., gray scale) inputs, we propose the first general approach, based on nanoscale metasurface optics, that can process RGB input data. Our system achieves up to an order of magnitude energy savings and simplifies the sensor design, all the while sacrificing little network accuracy.
Knowledge, attitudes, and practices towards COVID-19 among Venezuelans during the 2020 epidemic: An online cross-sectional survey
Authors: Bates Benjamin R. , Tami Adriana , Carvajal Ana , Grijalva Mario J. 
Published: April 2021

Background
COVID-19 threatens health systems worldwide, but Venezuela’s system is particularly vulnerable. To prevent the spread of COVID-19, individuals must adopt preventive behaviors. However, to encourage behavior change, we must first understand current knowledge, attitudes, and practices (KAPs) that inform response to this health threat.

Methods
We explored KAPs among Venezuelans using a cross-sectional, internet-based questionnaire. The questionnaire explored individuals’ knowledge about COVID-19; their attitudes toward the world’s and the Venezuelan authorities’ abilities to control it; and their self-reported practices. We also collected demographic data. Binomial logistic regression analyses were used to predict the adoption of preventive behaviors based on demographic variables, individual knowledge level, and individual attitudes.

Results
3122 individuals completed the questionnaire. Participants had a high level of knowledge about COVID-19. They expressed high levels of optimism that the world would eventually control COVID-19, but they were very pessimistic about the public authorities in Venezuela. Most participants adopted preventive practices. Binomial regression suggests younger people, less educated people, and manual laborers hold lower levels of knowledge, and these groups, as well as men, were less likely to adopt preventive practices. Knowledge, by itself, had no association with optimism and little association with self-reported practices.

Conclusions
As other KAP studies in Latin America found, knowledge is not sufficient to prompt behavior change. Venezuelans’ pessimism about their own country’s ability should be explored in greater depth. Health promotion in Venezuela may wish to target the most at risk groups: men, younger people, less educated people, and manual laborers.
A qualitative study of the first batch of medical assistance team’s first-hand experience in supporting the nursing homes in Wuhan against COVID-19
Authors: Yang Xiu-Fen , Li Meng-qi , Liao Lu-lu , Feng Hui , Zhao Si , Wu Shuang , Yin Ping 
Published: April 2021

Background
The pandemic of coronavirus disease 2019 (COVID-19) has global impact, Wuhan in Hubei province is a high-risk area. And the older people in nursing homes are the most susceptible group to COVID-19. The aim of this study was to describe the practice and experience of the first-line medical team, to provide insights of coping with COVID-19 in China.

Method
This qualitative study used a descriptive phenomenological design to describe the experience of medical staff supported the nursing homes in Wuhan fighting against COVID-19. Unstructured interviews via online video were conducted with seven medical staffs who supported the nursing homes in Wuhan. Data were analyzed using content analysis in five main themes: for nursing homes, we interviewed the difficulties faced at the most difficult time, services for the older people, and prevention and management strategies, for the medical staff, the psychological experience were interviewed, and the implications for public health emergencies were also reported.

Conclusions
It is imperative that effective preventive and response measures be implemented to face the outbreak of COVID-19 and meet the care needs of older people in the context of COVID-19.

Implications
Findings will inform managers of some reasonable instructional strategies for implementing effective infection management. Nursing homes need to provide targeted services to help alleviating their bad psychology for residents.
Repeated intermittent hypoxic stimuli to operative lung reduce hypoxemia during subsequent one-lung ventilation for thoracoscopic surgery: A randomized controlled trial
Authors: Yoon Susie , Kim Bo Rim , Min Se-Hee , Lee Jaehun , Bahk Jae-Hyon , Seo Jeong-Hwa 
Published: April 2021

Background
An intervention to potentiate hypoxic pulmonary vasoconstriction may reduce intrapulmonary shunt and hypoxemia during one-lung ventilation. Previous animal studies reported that repeated intermittent hypoxic stimuli potentiated hypoxic pulmonary vasoconstriction, but no clinical study has examined the effects of this intervention on hypoxemia during one-lung ventilation. We thus performed a single-center, parallel-group, double-blind, randomized controlled trial to investigate whether repeated intermittent hypoxic stimuli to the operative lung reduce hypoxemia during the subsequent one-lung ventilation for thoracoscopic surgery.

Methods
Patients undergoing one-lung ventilation were randomized into two groups (n = 68 each). Before one-lung ventilation, in the intermittent hypoxia group, the nondependent lung was not ventilated for 2 min and then ventilated for 2 min while the dependent lung was continuously ventilated. This was repeated five times. In the continuous normoxia group, both lungs were ventilated for 20 min. We measured SpO2, PaO2, FiO2, PaCO2, SaO2, and central venous oxygen saturation during one-lung ventilation. The primary outcome was the number of patients with hypoxemia defined as a SpO2 <95% during one-lung ventilation, which was analyzed with a chi-squared test.

Results
Hypoxemia was less frequent in the intermittent hypoxia group than in the continuous normoxia group during OLV [6/68 (8.8%) vs 17/68 (25.0%), risk ratio (95% CI) 0.35 (0.15–0.84), p = 0.012]. The PaO2 (p = 0.008 for 30 min and 0.007 for 60 min) and PaO2/FiO2 (p = 0.008 for both) were higher 30 and 60 min after starting one-lung ventilation, and the alveolar-arterial pressure gradient (p = 0.010) and shunt index (p = 0.008) were lower 30 min after starting one-lung ventilation in the intermittent hypoxia group than in the continuous normoxia group. Postoperative adverse events did not differ significantly between groups.

Conclusions
Repeated intermittent hypoxic stimuli to the operative lung seemed to potentiate hypoxic pulmonary vasoconstriction, and thus reduced hypoxemia during the subsequent one-lung ventilation.
The macroeconomic aspects of sport in Europe: a cross-country comparison
Authors: Mamcarczyk Mariola , Szyszko Magdalena 
Published: April 2021

In this paper we aim to investigate the importance of the sports sector of the economy for macrolevel performance in the European Union Member States. The problem that we address is worthy of research focus as sport is a dynamically expanding and important sector of the economy. The increasing importance of sport in national economies cannot be fully analysed due to the lack of sufficient statistical data. In this paper, we provide a comparison of the Eurostat sports collections results and Sport Satellite Account-based examination of the contribution of sport to the GDP and value added. The analysis of statistical data is preceded by a description of the sports sector measurement. We establish that the contribution of sport is more remarkable for developed economies, however it has also been increasing over time in other EU Member States. This can be observed for employment, changes in enterprises’ statistics, and international trade. Household spending on sports goods and services also increases even if the Great Recession led to a downturn in sport consumption in some countries. The frequency and coherence of sports data collections related to its economic significance is not satisfactory. The issue needs to be given a higher priority by public authorities.
Enabling the Environment for Private Sector Investment: Impact on Food Security and Poverty
Authors: Post Lori , Schmitz Andrew , Issa Tariq , Oehmke James 
Published: April 2021

Abstract
Millions of people worldwide live in extreme poverty, which has an adverse effect on global food security. Research shows that growth in the agricultural labor sector has twice the impact on poverty compared to growth in other labor sectors. To that end, we examine some of the enabling factors of private sector investment to increase food security and reduce poverty: innovative output, intellectual property rights innovation, gender-sensitive land tenure, creation of new businesses, openness to trade, government institutional flexibility, access to credit, inclusion of new sectors, income diversification, public-private partnerships, infrastructure improvements, payments for eco-system services, and climate-smart innovation. Developing policies that improve food security will help to reduce poverty.
Joint Improvisation, Minimalism and Pluralism about Joint action
Authors: Saint-Germier Pierre , Paternotte Cédric , Canonne Clément 
Published: April 2021

AbstractThis paper introduces freely improvised joint actions, a class of joint actions characterized by (i) highly unspecific goals and (ii) the unavailability of shared plans. For example, walking together just for the sake of walking together with no specific destination or path in mind provides an ordinary example of FIJAs, along with examples in the arts, e.g., collective free improvisation in music, improv theater, or contact improvisation in dance. We argue that classic philosophical accounts of joint action such as Bratman’s rule them out because the latter require a capacity for planning that is idle in the case of FIJAs. This argument is structurally similar to arguments for minimalist accounts of joint action (e.g., based on joint actions performed by children before they develop a full-fledged theory of mind), and this invites a parallel minimalist account, which we provide in terms of a specific kind of shared intentions that do not require plan states. We further argue that the resulting minimalist account is different in kind from the sort of minimalism suggested by developmental considerations and conclude in favor of a pluralistic minimalism, according to which there are several ways for an account of joint action to be minimal.