bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra-wide varifocal imaging with selectable region of interest capacity using Alvarez lenses actuated by a dielectric elastomer
Authors: Hao Qun , Chen Chuanxun , Cao Jie , Li Zhikuo , Cheng Yang
Published: May 2022

A remarkable feature of Alvarez lenses is that a wide focal length tuning range can be achieved using lateral displacement rather than commonly used axial translation, thus, reducing the overall length of varifocal imaging systems. Here, we present novel lens elements based on Alvarez lenses actuated by a dielectric elastomer (DE). The proposed lens elements are composed of the varifocal component and the scanning component. Based on the proposed lens elements, an imaging system is built to realize ultra-wide varifocal imaging with a selectable region of interest. The lens elements have a variable focus function based on an Alvarez lens structure and a DE actuator and a scanning function based on the DE-based four-quadrant actuators. The large deformation generated by the DE actuators permits the lateral displacement of the Alvarez lenses up to 1.145 mm. The focal length variation of the proposed varifocal component is up to 30.5 times, where the maximum focal length is 181 mm and the minimum focal length is 5.94 mm. The rise and fall times of the varifocal component are 160 ms and 295 ms, respectively. By applying different voltages on four-quadrant actuators, the scanning component allows the varifocal component to move in different directions and endows the varifocal component with a selectable region of interest imaging capability. The scanning range of the scanning component is 17.57°. The imaging resolution of the imaging system is approximately 181 lp/mm. The system developed in the current study has the potential to be used in consumer electronics, endoscopy, and microscopy in the future.
Rethinking human resources and capacity building needs for malaria control and elimination in Africa
Authors: Mwenesi Halima , Mbogo Charles , Casamitjana Núria , Castro Marcia C. , Itoe Maurice A. , Okonofua Friday , Tanner Marcel
Published: May 2022

Despite considerable success in controlling malaria worldwide, progress toward achieving malaria elimination has largely stalled. In particular, strategies to overcome roadblocks in malaria control and elimination in Africa are critical to achieving worldwide malaria elimination goals—this continent carries 94% of the global malaria case burden. To identify key areas for targeted efforts, we combined a comprehensive review of current literature with direct feedback gathered from frontline malaria workers, leaders, and scholars from Africa. Our analysis identified deficiencies in human resources, training, and capacity building at all levels, from research and development to community involvement. Addressing these needs will require active and coordinated engagement of stakeholders as well as implementation of effective strategies, with malaria-endemic countries owning the relevant processes. This paper reports those valuable identified needs and their concomitant opportunities to accelerate progress toward the goals of the World Health Organization’s Global Technical Strategy for Malaria 2016–2030. Ultimately, we underscore the critical need to re-think current approaches and expand concerted efforts toward increasing relevant human resources for health and capacity building at all levels if we are to develop the relevant competencies necessary to maintain current gains while accelerating momentum toward malaria control and elimination.
Modeling robust COVID-19 intensive care unit occupancy thresholds for imposing mitigation to prevent exceeding capacities
Authors: Runge Manuela , Richardson Reese A. K. , Clay Patrick A. , Bell Arielle , Holden Tobias M. , Singam Manisha , Tsuboyama Natsumi , Arevalo Philip , Fornoff Jane , Patrick Sarah , Ezike Ngozi O. , Gerardin Jaline
Published: May 2022

In non-pharmaceutical management of COVID-19, occupancy of intensive care units (ICU) is often used as an indicator to inform when to intensify mitigation and thus reduce SARS-CoV-2 transmission, strain on ICUs, and deaths. However, ICU occupancy thresholds at which action should be taken are often selected arbitrarily. We propose a quantitative approach using mathematical modeling to identify ICU occupancy thresholds at which mitigation should be triggered to avoid exceeding the ICU capacity available for COVID-19 patients and demonstrate this approach for the United States city of Chicago. We used a stochastic compartmental model to simulate SARS-CoV-2 transmission and disease progression, including critical cases that would require intensive care. We calibrated the model using daily COVID-19 ICU and hospital census data between March and August 2020. We projected various possible ICU occupancy trajectories from September 2020 to May 2021 with two possible levels of transmission increase and uncertainty in core model parameters. The effect of combined mitigation measures was modeled as a decrease in the transmission rate that took effect when projected ICU occupancy reached a specified threshold. We found that mitigation did not immediately eliminate the risk of exceeding ICU capacity. Delaying action by 7 days increased the probability of exceeding ICU capacity by 10–60% and this increase could not be counteracted by stronger mitigation. Even under modest transmission increase, a threshold occupancy no higher than 60% was required when mitigation reduced the reproductive number Rt to just below 1. At higher transmission increase, a threshold of at most 40% was required with mitigation that reduced Rt below 0.75 within the first two weeks after mitigation. Our analysis demonstrates a quantitative approach for the selection of ICU occupancy thresholds that considers parameter uncertainty and compares relevant mitigation and transmission scenarios. An appropriate threshold will depend on the location, number of ICU beds available for COVID-19, available mitigation options, feasible mitigation strengths, and tolerated durations of intensified mitigation.
A real-world prospective study on dialysis-requiring acute kidney injury
Authors: Gomes Conrado Lysandro R. , Yamane Thais Lira Cleto , Ruzany Frederico , Rocco Suassuna José Hermógenes
Published: May 2022

Background

Current information about acute kidney injury (AKI) epidemiology in developing nations derives mainly from isolated centers, with few quality multicentric epidemiological studies. Our objective was to describe a large cohort of patients with dialysis-requiring AKI derived from ordinary clinical practice within a large metropolitan area of an emerging country, assessing the impact of age and several clinical predictors on patient survival across the spectrum of human life.

Methods

We analyzed registries drawn from 170 hospitals and medical facilities in Rio de Janeiro, Brazil, in an eleven-year period (2002–2012). The study cohort was comprised of 17,158 pediatric and adult patients. Data were analyzed through hierarchical logistic regression models and mixed-effects Cox regression for survival comparison across age strata.

Results

Severe AKI was mainly hospital-acquired (72.6%), occurred predominantly in the intensive care unit (ICU) (84.9%), and was associated with multiple organ failure (median SOFA score, 11; IQR, 6–13). The median age was 75 years (IQR, 59–83; range, 0–106 years). Community-acquired pneumonia was the most frequent admission diagnosis (23.8%), and sepsis was the overwhelming precipitating cause (72.1%). Mortality was 71.6% and was higher at the age extremes. Poor outcomes were driven by age, mechanical ventilation, vasopressor support, liver dysfunction, type 1 cardiorenal syndrome, the number of failing organs, sepsis at admission, later sepsis, the Charlson score, and ICU admission. Community-acquired AKI, male gender, and pre-existing chronic kidney disease were associated with better outcomes.

Conclusions

Our study adds robust information about the real-world epidemiology of dialysis-requiring AKI with considerable clinical detail. AKI is a heterogeneous syndrome with variable clinical presentations and outcomes, including differences in the age of presentation, comorbidities, frailty state, precipitation causes, and associated diseases. In the cohort studied, AKI characteristics bore more similarities to upper-income countries as opposed to the pattern traditionally associated with resource-limited economies.
Individual and community-level determinants of underweight among lactating mothers in Ethiopia: A multilevel analysis
Authors: Teferu Zinash , Tekalegn Yohannes , Sahiledengle Biniyam , Zenbaba Demisu , Desta Fikreab , Seyoum Kenbon , Gezahegn Habtamu , Shiferaw Damtew Solomon , Mamo Ayele , Chattu Vijay Kumar
Published: May 2022

Background

Determining the nutritional status of lactating women is important because underweight lactating mothers will have low energy levels and reduced cognitive abilities, which will affect the inadequate care of their young children. Thus, malnutrition is passed down from generation to generation, perpetuating the vicious cycle. There is scarce national data on determinants of underweight among lactating mothers in Ethiopia. Hence, this study aimed to identify individual and community-level determinants of underweight among lactating mothers in Ethiopia.

Methods

Data from the Ethiopian Demographic and Health Survey (EDHS) from 2016 were used. A total of 3848 lactating mothers were included in this study, and a multilevel, multivariable logistic regression model was fitted to identify determinants of underweight among lactating mothers.

Results

The odds of being underweight among rural lactating mothers were 65% higher (AOR = 1.65, 95% CI = 1.13, 2.41) than lactating mothers in the urban area. The odds of being underweight among lactating mothers who have toilet facilities were 33% lower (AOR = 0.67, 95%CI = 0.54, 0.83) compared with those do not have toilet facilities. Those mothers in the age group of 25–34 years and greater than 35 years had (AOR = 0.61,95%CI = 0.48, 0.79), and (AOR = 0.66, 95%CI = 0.47, 0.95) times lower chance of being underweight compared with those who had 15–24 years of age, respectively. The likelihood of being underweight among lactating mothers in high community poverty (AOR = 1.40, 95%CI = 1.08, 1.82) was higher than the lower community poverty level.

Conclusion

Underweight among lactating mothers was significantly associated with individual-level (age and toilet facilities) variables and community-level (residence and community poverty). Therefore, focusing on these identified factors could improve underweight among lactating mothers in Ethiopia.
COVID-19 hospitalization and mortality and hospitalization-related utilization and expenditure: Analysis of a South African private health insured population
Authors: Solanki Geetesh , Wilkinson Thomas , Bansal Shailav , Shiba Joshila , Manda Samuel , Doherty Tanya
Published: May 2022

Background

Evidence on the risk factors for COVID-19 hospitalization, mortality, hospital stay and cost of treatment in the African context is limited. This study aims to quantify the impact of known risk factors on these outcomes in a large South African private health insured population.

Methods and findings

This is a cross sectional analytic study based on the analysis of the records of members belonging to health insurances administered by Discovery Health (PTY) Ltd. Demographic data for 188,292 members who tested COVID-19 positive over the period 1 March 2020–28 February 2021 and the hospitalization data for these members up until 30 June 2021 were extracted. Logistic regression models were used for hospitalization and death outcomes, while length of hospital stay and (log) cost per patient were modelled by negative binominal and linear regression models. We accounted for potential differences in the population served and the quality of care within different geographic health regions by including the health district as a random effect. Overall hospitalization and mortality risk was 18.8% and 3.3% respectively. Those aged 65+ years, those with 3 or more comorbidities and males had the highest hospitalization and mortality risks and the longest and costliest hospital stays. Hospitalization and mortality risks were higher in wave 2 than in wave 1. Hospital and mortality risk varied across provinces, even after controlling for important predictors. Hospitalization and mortality risks were the highest for diabetes alone or in combination with hypertension, hypercholesterolemia and ischemic heart disease.

Conclusions

These findings can assist in developing better risk mitigation and management strategies. It can also allow for better resource allocation and prioritization planning as health systems struggle to meet the increased care demands resulting from the pandemic while having to deal with these in an ever-more resource constrained environment.
Capture, analyse, visualise: An exemplar of performance analysis in practice in field hockey
Authors: Lord Felicity , Pyne David B. , Welvaert Marijke , Mara Jocelyn K.
Published: May 2022

The goal of performance analysis is to capture the multitude of factors that affect sports strategy, and present them in an informative, interpretable, and accessible format. The aim of this study was to outline a performance analysis process in field hockey that captures, analyses and visualises strategy in layers of detail culminating in the creation of an RStudio Shiny application. Computerised notational analysis systems were developed to capture in-game events and ball tracking data of 74 matches from the Women’s Pro League 2019. Game styles were developed using k-means cluster analysis to reduce detailed in-game events into practical profiles to identify the attack types, game actions and tempo of a team’s strategy. Ball movement profiles were developed to identify the predictability (entropy) and direction (progression rates) of ball movements, and consequent distribution of possession in different attacking zones. The Shiny application, an interactive web-platform, links the information from simple game profiles with detailed game variables to understand each teams’ holistic game plan, how they are different, and how to exploit these differences. The process outlined can be applied to any team invasion sport to understand, develop and communicate successful strategies under different match situations.
A Study of Victorian Teachers’ Beliefs About Student Behaviour and Their Perception of Preparation and Confidence to Engage inand Their Perception of Preparation and Confidence to Engage in Evidence-based Behaviour SupportEvidence-based Behaviour Support
Authors:   Monash University, Fox Russell , Sharma Umesh ,   Monash University, Leif Erin ,   Monash University
Published: May 2022

Positive and proactive approaches to behaviour support have been recognised as one component required to create effective and inclusive school environments (Finkelstein et al., 2019). States and territories within Australia have increasingly adopted school- wide positive behavioural interventions and supports (SWPBIS) as a means to creating effective social and behavioural change (Poed & Whitefield, 2020). However, ensuring staff implement SWPBIS as it is intended has been a challenge, both in Australia and internationally (McIntosh et al., 2016; NSW Ombudsman, 2017). The current study identifies and seeks to address two gaps in the existing literature exploring noted barriers to the successful and sustained implementation of SWPBIS. First, limited exploration of teachers’ perceptions of their preparation (pre-service and in-service) and confidence to engage in SWPBIS practices and supports has been undertaken in Australia. Additionally, the degree to which teachers agree with a functional approach to understanding and supporting student behaviour has not been undertaken in an Australian context. The findings from such exploration may be used to inform the development of teacher training programs, and support efforts to successfully and sustainably implement SWPBIS in Australian schools.
Elemental and Thermogravimetric Analysis of Plastic-Paper Composites as Refuse-derived Fuels for Energy Generation.
Authors: Gaji Muhammed  Musa , Ejilah Robinson , Isah Mohammed  Yakub
Published: May 2022

Waste generation in Nigerian cities continue to rise with increasing population. Where and how to effectively and efficiently channel these wastes remains a serious challenge for the nation. In this study, plastic and paper waste samples were collected – as received, dried and sorted manually into sub-fractions, pulverized and homogenized in prescribed mixing ratio by weight, and compacted into briquettes. The elemental analysis to determine the carbon (C), hydrogen (H), nitrogen (N), sulphur (S), and oxygen (O) content of the samples was carried out in accordance with ASTM D3176-15 standard using an element analyzer. While, thermogravimetric tests were performed on the samples in a thermal analyser according to IUPAC procedure. The results revealed that; plastic –paper composite samples in the group exhibited a lower elemental carbon and hydrogen than the pure (PL100) plastic benchmark; the tested composite samples displayed a comparably higher presence of elemental oxygen, with exception of the composite sample with 25wt%. of paper; it was evident that plastic-paper composite samples with 25 wt%., 50wt%., and 75wt%. of paper exhibited 0.08 %, 0.04 %, and trace % increase in sulphur content, while for sample with 100wt%. of paper showed a decrease in elemental sulphur by 0.04wt%. Based on the peak temperature at the maximum weight loss rate indicating sample combustibility, samples PL100 with DTG peak temperatures (417.08- 474.62
oC), PL50+PA50 (383.27- 441.47
oC) and PL75+PA25 (373.70- 426.41
oC) are more combustible than samples PL5+PA95 (322.52+ 402.05
oC) and PA100 (367.48
oC), and would be recommended for use as refuse-derived fuel for on account of their energy recovery potentials.
Death of Globalization during COVID-19 Era
Authors: Kanwal Maria
Published: May 2022

COVID-19 plague has accompanied in novel environment of ambiguity which is powering isolationism and playing within nationalist descriptions. Pandemic is threatening Globalization as government disorganize to diminish their weakness to virus by restricting movement of people and global trade. Closure of borders and by taking severe measures against migration results into disturbances in international supply chain along with disadvantageous impacts upon employment. Vital and courageous policy procedures are desired not only for saving the lives of people but also to safeguard the world from economic destructions and also for sustaining the economic development and financial steadiness. This pandemic is not only the health crisis rather it is considered as social, health and economic crisis. COVID-19 which is categorized as pandemic by World Health Organization (WHO) is harming the world at its central. Worldwide economy has been decreased up to 1 % during 2020 because of coronavirus. United Nation stated that worldwide economy will be further goes in decline if limitations upon economic events are prolonged. There is a devastating decline in Foreign Direct Investment (FDI) because of COVID-19. Multinational Enterprises (MNEs), investments and local businesses have been dangerously damaged with profound economic and social consequences. COVID-19 is considered as a threat to economy as well as to public health. COVID-19 which first occurred in Wuhan city and it affects 131,020,967 people all over the world till 5 April 2021 as reported by World Health Organization (WHO). The continuing outspread of coronavirus has developed as major threat to financial markets and global economy.
DHANWANTARI
Authors: Tiwari Ansh
Published: May 2022

When patients receive care or services, inefficiency can be defined as using more inputs (or resources) than is necessary, and it is associated with unnecessary variation in operational and clinical processes. Among the 8.6 million preventable deaths in 2016, more than 1 million were caused by neonatal problems and tuberculosis in those who accessed the health system but received poor quality of care.
Success in America
Authors: Clark Ian
Published: May 2022

I belong to a generation ridiculed; accused of being lazy, lacking a good work ethic, at home living in someone’s basement. Though I soundly reject these derisions, I understand what so-called millennials find abhorrent about the average American’s work - life balance. Can redefining success within the United States aid in allowing its people to achieve both better health and a more secure sense of well-being? Additionally What effect does the American construct of success have on the well-being of an individual? Additionally, does a wealth and “work without complaint” centered interpretation of the American Dream have a positive, negative, or neutral effect on the well-being of an individual? Lastly, wha
Transformaciones de la imagen de una ciudad: repercusiones de la renovación urbana
Authors: Vergara Durán Ricardo Adrián
Published: May 2022

Las ciudades de Latinoamérica se encuentran en un proceso irreversible que abarca tanto crecimiento demográfico, crecimiento económico y crecimiento de la extensión urbana. Mientras que existen áreas de expansión en las periferias que apenas comienzan a ser incorporadas con usos urbanos, y áreas que inicialmente fueron periféricas pero que se encuentran ya completamente consolidadas y urbanizadas espacial, estructural y funcionalmente en muchas áreas centrales y especialmente en muchos centros históricos se presentan unos procesos de desarticulación, degradación y subutilización que impiden un aprovechamiento efectivo de tales áreas. La imagen de la ciudad, la imagen que la ciudad proyecta (hacia adentro) a sus propios habitantes y hacia fuera es un elemento muy importante a tener en cuenta como una de las capacidades y fortalezas que a través de la renovación de los centros históricos puede reforzarse o dado el caso cambiarse. En el artículo se presentan elementos iniciales de discusión en este aspecto que cada vez cobra más importancia en la discusión de la renovación de centros históricos en Latinoamérica.
Notas sobre el tráfico de esclavos en Santiago de Cuba
Authors: Belmonte Postigo Jose Luis
Published: May 2022

El presente artículo pretende establecer los patrones que rigieron el comercio de esclavos en Santiago de Cuba en los primeros años de la liberalización de la trata, prestando especial atención a los puertos de origen de las embarcaciones y la conformación de las cargas de esclavos, así como a su periodicidad. La habilitación de Santiago de Cuba como puerto negrero para embarcaciones españolas se tradujo en la introducción de un elevado número de esclavos, que incidieron en el auge del esclavismo en la región y el desarrollo de los sistemas de plantación azucarero y cafetalero.
Salud y calidad de vida autopercibida de los adultos mayores en un municipio del caribe colombiano
Authors: Villarreal Amaris Gloria Esther , Pérez Aguas Claudia Patricia , Usta Carrillo Adela
Published: May 2022

Objetivo: Determinar la relación entre calidad de vida y salud auto percibida en adultos mayores atendidos en las Instituciones Prestadoras de Servicios de Salud en un municipio del Caribe Colombiano. Metodología: Se realizó un estudio descriptivo de tipo transversal con diseño observacional y con una fase correlacional, en una muestra de 365 adultos mayores seleccionados probabilísticamente que asisten al programa del Adulto mayor en las diferentes Instituciones prestadoras de servicios de salud en un municipio del Caribe Colombiano.Se aplicó una encuesta sociodemográfica, el Índice multicultural de calidad de vida y la inclusión de dos preguntas para medir la salud auto percibida. Se usó la estadística descriptiva y un modelo de regresión logística multivariada. Se mantuvo la confidencialidad de la información, el anonimato de los participantes y se diligenció el consentimiento informado. Resultados: La percepción global de la calidad de vida en un 54% fue deficiente, como regular en un 56 % auto perciben su salud como positiva; y un 44% (161) como negativa. Las dimensiones con mayores puntuaciones fueron Bienestar psicosocial (55%), autocuidado y funcionamiento (52%), funcionamiento interpersonal (52%), satisfacción espiritual (60%) y con menor puntuación: bienestar físico (51%), apoyo social (50) y satisfacción personal (51%). Conclusión: Se encontró relación en las variables de calidad de vida y de salud auto percibida en cuanto a mayor autonomía hay buena percepción de la salud, pero a mayor deterioro físico, insatisfacción interpersonal y deficiente apoyo social los adultos mayores tienen baja percepción global de su calidad de vida y de su salud.
Impact of sodium citrate ingestion during recovery after strenuous exercise in the heat on heart rate variability: A randomized, crossover study
Authors: Fiedler Janis , Šmite Zane , Suvi Silva , Timpmann Saima , Mooses Martin , Medijainen Luule , Unt Eve , Ööpik Vahur
Published: May 2022

Changes in hydration status influence plasma volume (PV) which is associated with post‐exercise parasympathetic reactivation. The present study hypothesized that, after dehydrating cycling exercise in the heat (DE), stimulation of PV expansion with sodium citrate (CIT) supplementation would promote heart rate variability (HRV) recovery in endurance‐trained men. Twelve participants lost 4% of body mass during DE. During subsequent 16‐h recovery, participants consumed water ad libitum (CIT =5.5‐L, PLC =5.1‐L) and ate prescribed food supplemented with CIT or placebo in a randomized, double‐blind, crossover manner. Relative changes in PV were assessed across DE and 16‐h recovery. HRV was analyzed before and 16 h after DE in three conditions for altogether four 5‐min periods: supine in a thermoneutral environment, supine in the heat (32°C, 46% relative humidity; 2 periods), and standing in the heat. A larger expansion of PV across 16‐h recovery occurred in CIT compared to placebo trial (p < 0.0001). However, no between‐trial differences appeared in HRV parameters (lnRMSSD, lnSDNN, lnLF/HF) in any 5‐min period analyzed before or 16 h after DE (in all cases p > 0.05). Increases in HR (p < 0.001) and lnLF/HF (p = 0.005) and decreases in lnRMSSD (p < 0.001) and lnSDNN (p < 0.001) occurred following DE in both trials. Larger PV expansion induced by CIT supplementation after DE does not improve recovery of HRV at rest and has no influence on HRV responsiveness in endurance‐trained men.
Effects of training on plasmatic cortisol and testosterone in football female referees
Authors: Muscella Antonella , My Giulia , Okba Selmi , Zangla Daniele , Bianco Antonino , Marsigliante Santo
Published: May 2022

There is very little about the impact that sports training has on female football referees. Therefore, we determined the effects of a 40‐week physical preparation, including a full football season, on plasma testosterone and cortisol concentrations and physical performance in female football referees. Plasma cortisol and testosterone concentrations were assayed together with fitness tests at the beginning of the training period (T0, in September), after 8 weeks from T0 (T1), at the mid of the season (T2, 24 weeks after T0), and at the end of the season (T3, in June, 40 weeks after T0). Plasma cortisol increased during the first period and up to T2 (from 15.4 ± 4.7 to 28.5 ± 3.9 µg/dl; p < 0.001), and then decreased at the end of the season (T3: 16.0 ± 2.4 µg/dl). Plasma testosterone concentration in T0 was 14.2±0.37 µg/dl and increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) and then decreased in T3 (33.5 ± 2.8 µg/dl). Resting testosterone levels in women were very low (14,2 ± 0.37 µg/dl) (Figure 3c). Testosterone increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) whilst, at the end of the season, its concentration decreased (33.5 ± 2.8 µg/dl) (Figure 3c). Significant improvements were observed in all physical performances during the observed period (ANOVA, p < 0.05). Finally, testosterone and cortisol concentrations significantly (p < 0.0001 for both) correlated with maximal oxygen consumption. In T1, testosterone concentration was also significantly correlated with running speed test (p < 0.001). In conclusion, training induces endocrine changes in order to maintain body homeostasis in women referees. It is important that coaches and sports scientists regularly observe changes in endocrine function induced by training and matches in female referees, because they can help maximize referees’ performance and limit cases of overtraining.
A wood-mimetic porous MXene/gelatin hydrogel for electric field/sunlight bi-enhanced uranium adsorption
Authors: Chen Lin , Sun Ye , Wang Jiawen , Ma Chao , Peng Shuyi , Cao Xingyu , Yang Lang , Ma Chunxin , Duan Gaigai , Liu Zhenzhong , Wang Hui , Yuan Yihui , Wang Ning
Published: May 2022

Although diverse uranium (U) adsorbents have been explored, it is still a great challenge for high-efficient uranium extraction form seawater. Herein a wood-mimetic oriented porous Ti3C2T
x
-MXene/gelatin hydrogel (MGH) has been explored through growing directional ice crystals cooled by liquid nitrogen and subsequently forming pores by freeze-dry (Ice-template) method, for ultrafast and high-efficient U-adsorption from seawater with great enhancement by both electric field and sunlight. Different from disperse Ti3C2T
x
-MXene powder, this MGH not only can be easily utilized but also can own ultrahigh specific surface area for high-efficient U-adsorption. The U-adsorbing capacity of this MGH (10 mg) can reach 4.17 mg·g−1 after only 1 week in 100 kg of seawater, which is outstanding in existing adsorbents. Furthermore, on the positive pole of 0.4 V direct current source or under 1-sun irradiation, the U-adsorbing capacity of the MGH can increase by 57.11% and 13.57%, respectively. Most importantly, the U-adsorption of this hydrogel can be greatly enhanced by simultaneously using the above two methods, which can increase the U-adsorbing capacity by 79.95% reaching 7.51 mg·g−1. This work provides a new biomimetic porous MXene-based hydrogel for electric field/sunlight bi-enhanced high-efficient U-extraction from seawater, which will inspire new strategy to design novel U-adsorbents and systems.
Effect of brackish water irrigation on the movement of water and salt in salinized soil
Authors: Zhang Panpan , Shen Jianglong
Published: May 2022

In China, fresh water resources are scarce, while brackish water resources are abundant. Reasonable utilization of brackish water is one of the important measures to alleviate the contradiction of water shortage. In order to study the effect of brackish water irrigation on water and salt transport in saline-alkali soils, one-dimensional brackish water infiltration experiments of soil columns were conducted. The influence of brackish water with different salinities on water and salt transport in salinized soil was compared and analyzed. The results showed that under brackish water irrigation, the Kostiakov model could better simulate the change in soil infiltration rate with time, the soil infiltration capacity had a positive response to the salinity of irrigation water. There was a good linear relationship between cumulative infiltration and the wetting front distance. Under different salinity conditions, the depth of soil desalination, Na+, and Cl− removal is different, which are inversely proportional to the degree of salinity; with the increase in the salinity of irrigation water, the water salt content and the concentration of Na+ and Cl− increased gradually, but the difference in the desalination zone was not obvious. Therefore, brackish water irrigation has a certain effect on the distribution of water and salt in saline soil.
Stomach-affecting intestinal parasites as a precursor model of Pheretima posthuma treated with anthelmintic drug from Dodonaea viscosa Linn.
Authors: Pandiyan Rajesh , Samiappan Sumathi C. , Sugumaran Abimanyu , Sivakumar Subpiramaniyam
Published: May 2022

The preponderance of helminth contagions is constrained to tropical regions and can cause massive vulnerability to malnutrition, anemia, pneumonia, and eosinophilia. Many human parasitic diseases cause severe illness in endemic populations. The helminths transmitting through the gastro-intestinal tract may develop resistance to anthelmintic drugs. The phytotherapy, anthelmintic, and antimicrobial efficacy of Dodonaea viscosa leaf solvent extracts were examined. Phytochemical screening was carried out by ultraviolet (UV) and Fourier transform infrared spectroscopy (FTIR). The anthelmintic activity was performed against a South Indian earth worm as a model by measuring the paralytic time. The antibacterial activity was performed against Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus, which stimulate the stomach helminths. Phytochemical screening revealed the presence of chemical compounds from the UV spectrum, and alkenes and aromatic compounds were confirmed by FTIR. Higher concentrations of the D. viscosa extract showed a rapid paralytic effect with a rapid death rate and histopathology. The zone-of-inhibition study indicated the potent antibacterial activity of the ethanolic and methanolic extracts of D. viscosa against different bacterial species. The current research revealed that D. viscosa has significant anthelmintic and antibacterial activities and it can be used for further elucidation and characterization.
Utilization of wild species for diversifying the cytoplasmic male sterility source of sunflower (Helianthus annuus L.) hybrids
Authors: Sharma Manish , Yediyur Gavisiddaiah Shadakshari , Rao Annabathula Mohan , Ramesh Sampangi
Published: May 2022

The present investigation is directed at improving sunflower using hybrids having diverse cytoplasmic male sterile (CMS) sources from Helianthus annuus and H. argophyllus. The aim is to develop and identify promising lines and hybrids with a high combining ability and to obtain highly productive oilseed sunflower hybrids having diverse CMS sources. Five diversified CMS lines and 10 testers were crossed in a line × tester mating design to develop 50 F1 hybrids for genetic analysis. The pooled analysis of variance revealed significant differences among hybrids for the traits studied. The mean squares of lines and testers from crosses and GCA variance components revealed the prevalence of additive variances and additive gene action. The mean squares of lines × tester interactions were also significant for all the traits considered. The significance of lines × tester interactions and SCA variance components indicated that SCA is also important in the expression of traits and demonstrated the role of dominant and epistatic genes in controlling the various traits. Among the diverse CMS lines, ARG-6-3-1-4was identified as the best general combiner for stem diameter, volume weight, seed yield, hull content and oil content. While, the line ARG-2-1-2 was the best general combiner for days to 50 per cent flowering, head diameter, 100 seed weight and seed filling per cent. The tester M17-R was observed to be the best general combiner for earliness and volume weight, while RHA 93 was the best general combiner for plant height, seed yield and oil content. The crossMUT-2-8-3-2 × GKVK 3 was found to be a good specific combiner for stem diameter, 100 seed weight, seed yield, seed filling percentage and oil content while, ARG-6-3-1-4 × GKVK 3 was a good specific combiner for days to 50% flowering, plant height and 100 seed weight. The highest standard heterosis for seed yield was observed in the hybrid MUT-2-8-3-2 × GKVK 3 followed by ARG-2-1-2 × LTRR 822 while for oil content the highest was seen in the cross ARG-6-3-1-4 × RHA95-C-1 and thus these hybrids can be exploited for sunflower improvement and diversifying the cytoplasmic male sterile sources of this valuable oilseed crop.
Microstructural study of concrete performance after exposure to elevated temperatures via considering C–S–H nanostructure changes
Authors: Amiri Mohammad , Aryanpour Marzieh , Porhonar Fatemeh
Published: May 2022

Evaluation of the concrete behavior in elevated temperatures is important in terms of first, structural construction safety under specified loadings, and second, measuring the loading capacity to continue operation. Furthermore, concrete behavior at high temperatures is strongly affected by microstructure. The calcium silicate hydrate (C–S–H), a nanostructure which is produced by hydration of cement paste, plays a significant role in enhancing the concrete strength under the impression of thermal fluctuations. Hence, this study investigates the microstructural performance of concrete exposed to high temperatures with a special focus on C–S–H nanostructure. Accordingly, 300 samples were cured for 1, 3, 7, 14, and 28 days in a moist room and then exposed to temperature range of 25–900°C for 2 h to investigate changes in their weight, length, compressive strength, and cracking behavior. Besides evaluating the microstructural behavior of the specimens in different temperatures, several techniques such as SEM, EDX, and XRD have been employed. Based on the results, any changes in the samples’ length, weight, and compressive strength depend on the C–S–H nanostructure behavior. In fact, following water decomposition from the C–S–H nanostructure at 900°C, the structure is partially converted to porous ceramic. These structural changes have caused a decline of 79–100% of the compressive strength. The compressive strength has decreased from 27.6 MPa to about 6 MPa. Also, the weight loss percentage of 28-days-old sample at this temperature was 18.84%. Based on the SEM and XRD results, this decline under high temperature arises due to the collapse of C–S–H nanostructure and formation of calcium oxide in the cement structure.
Optimization of electrocoagulation process for treatment of rice grain-based biodigester distillery effluent using surface response methodology approach
Authors: Dubey Savita , Parmar Nitesh , Rekhate Chhaya , Prajapati Abhinesh Kumar
Published: May 2022

Distillery industries are the most water-consuming industries discharging a large amount of wastewater that contain a high organic load. Hence it is first treated in biodigester where significant organics reduces (50–60%) and the outcome of biodigester is commonly known as biodigester effluent (BDE). The present study is an attempt to treat BDE in terms of COD and color removal using a batch electrocoagulation reactor (ECR) where stainless steel (SS) is used as an electrode. To optimize the four independent parameters namely initial pH (pHi: 3.5–9.5), current density (j: 49.5–247 A/m2), electrode gap (g: 1.2–3.2 cm), and reaction time (t: 20–100 min) on the color and COD reduction efficiency, a central composite design (CCD) experiment is applied to evaluate the individual and interactive effects of these parameters. The high coefficients of determination for color (R
2 = 0.9989) and COD (R
2 = 0.9981) were obtained by analysis of variance (ANOVA) between the experimental data and the predicted data using a second-order regression model. At the optimum condition color and COD removal of 81.4 and 91.9%, respectively, were observed. A material balance of SS has also been incorporated.
Optimization of baseline configuration in a GNSS network (Nile Delta network, Egypt) – A case study
Authors: Farhan Magda , Gomaa Mahmoud , Sedeek Ahmed
Published: May 2022

When starting any GNSS measurements, there is a need to establish a survey plan with the required optimal baselines. The optimal GNSS baselines can be chosen by solving the geodetic second-order design (SOD). The particle swarm optimization PSO is used widely to solve geodetic design issues. This work employed the particle swarm optimization (PSO) algorithm, a stochastic global optimization method, to select the optimal GNSS baselines. The optimal baselines satisfy the set criterion matrix at a reasonable cost. The fundamentals of the algorithm are presented. The effectiveness and usefulness of the technique are then demonstrated using a Nile Delta GNSS network as an example. In some cases, we have to observe many GNSS benchmarks with limited instrumentations. PSO represents a powerful tool for optimizing baseline to get the required accuracy with limited capabilities (like limited receivers). The PSO algorithm, a stochastic global optimization approach, was used in this paper to find the best observation weights to measure in the field that will match the predetermined criterion matrix with a fair degree of precision. The method’s fundamentals are presented with an actual geodetic network over the Nile delta in Egypt. In the current work, two survey strategies were applied. One represents a case with 9 GNSS receivers (high capability), and another one represents the tested survey plan with limited GNSS receivers (3 receivers, low capability) after applying PSO. By comparing two survey strategies, applying the PSO algorithm to a real Nile delta geodetic network shows its effectiveness on the obtained coordinate accuracy. This obtained accuracy ranged from 2 mm to 3 mm in X, Y, Z, and 3 mm in height. Also, the linear closure error between known and estimated coordinates improved to be 1.4 cm after applying PSO.
Atraumatic spontaneous splenic rupture in a female COVID-19 patient
Authors: Melamed Michele T. , Gigliotti Jake L.
Published: May 2022

Coronavirus disease (COVID-19), an infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has severely ravaged the world since the end of 2019. Although most cases range from mild to severe with primarily respiratory symptoms, there have been some unusual clinical presentations, one of which is described in this case report. A 30 year-old woman with no significant medical history presented to the emergency department (ED) in October 2020 with sudden onset of severe left upper and lower abdominal pain. Her initial triaged blood pressure was 70 mmHg systolic, associated with mild tachycardia. Her beta human chorionic gonadotropin (beta-hCG) was negative, and her initial hemoglobin was 9.3 g/dL. A bedside ultrasound (US) was immediately performed, which showed moderate free fluid in the pelvis as well as in the right and left upper quadrants of the abdomen. She was stabilized with a fluid bolus and later underwent a CT scan of the abdomen and pelvis, which showed an apparent grade III splenic laceration without active extravasation. The patient underwent a successful embolization procedure by interventional radiology (IR) and was discharged from the hospital 2 days later. The initial medical workup included a positive polymerase chain reaction (PCR) COVID-19 test but included no other findings that could serve as a cause for her spleen to spontaneously rupture. The purpose of this case report is to illustrate and make other clinicians aware of unusual potential complications and clinical presentations of COVID-19. The condition of spontaneous splenic rupture (SSR) is an uncommon but an emergent differential diagnosis in an otherwise healthy person with potential drastic outcomes. A careful approach in the management and care of these patients is warranted. This is one of a handful of case reports on SSR secondary to COVID-19 to the best of our knowledge.
Effect of different joint angles on the mechanical strength of adhesive-bonded scarf and double butt–lap joints
Authors: Yanen Cenk , Solmaz Murat Yavuz
Published: May 2022

The effect of different joint angles and joint types in adhesively bonded joints was investigated. Two joint types were chosen to examine the effect of the joint type. A total of 12 samples were produced at six different angles (30°, 45°, 52°, 60°, 75°, and 90°) to examine the effect of joint angle on the scarf and double butt–lap joint types. St 37 steel was used as the adherend material. The adhesion distance, sample thickness, and adhesion area were kept constant in the samples. There were differences in the sample widths to make the angle change by keeping the adhesive bonding length constant. 3M Scotch-Weld DP810 epoxy adhesive was used as the adhesive. The adhesive thickness was chosen as 0.1 mm. An axial tensile load was applied to the samples, and the results were recorded and evaluated. When scarf and double butt–lap joint samples are compared with each other according to their angles, it was seen that double butt–lap joints were more successful in samples with 30, 45, and 52° joint angles, and scarf lap joints were more successful in samples with 60, 75, and 90° joint angles.
Microstructure analysis and mechanical properties of electron beam powder bed fusion (PBF-EB)-manufactured γ-titanium aluminide (TiAl) at elevated temperatures
Authors: Kotzem Daniel , Teschke Mirko , Juechter Vera , Körner Carolin , Walther Frank
Published: May 2022

Additively manufactured γ-titanium aluminide has a high specific strength and temperature resistance. This opens new possibilities for future lightweight constructions for aerospace applications. The objective of this work was to characterize additively manufactured Ti–48Al–2Cr–2Nb alloy specimens, which were successfully manufactured by electron beam powder bed fusion. For microstructural characterization, the as-built state was investigated with light and scanning electron microscopy. In the electron backscatter diffraction analysis, the size and the orientation of the grains were observed. The pore size and distribution were examined in computer tomographic scans, which showed a near fully dense material with a relative density of >99.9%. Furthermore, the hardness curve over the building height was examined in hardness mappings. Thereby, a strong decrease in hardness could be observed with an increase in part height. To evaluate the reliability of the manufactured alloy, quasi-static compression tests were carried out at temperatures up to 650 °C. Within these tests, a high compression strength (σ

c,p,0.2,650 °C = 684 MPa) was determined, which implicated a potential substitution of nickel-based superalloy components in aerospace applications under compressive loads.
Failure investigation of a spline half-shaft in a loader rickshaw differential system
Authors: Hayat Umer , Shad Muhammad Rizwan , Ali Ahmad , Abbas Hassan , Hassnain Muhammad
Published: May 2022

Large number of pre-mature failure cases of spline half-shafts of loader automobile rickshaws were encountered by an industry in Lahore, Pakistan. Unexpected fracture of the spline-region of half-shafts were reported shortly after the shafts were put to service. This paper presents the findings of a systematic investigation that was carried out to find the root cause of the failure. Visual inspection, mechanical characterization, microstructural analysis, and chemical composition analysis were used to study the failure. It was revealed that the failure was torsional fatigue fracture in nature, with crack initiating from one of the machining marks present near the spline-root. Main cause of failure was found to be stress concentration at machine marks present on the surface, especially the ones closer to spline-roots, resulting in crack initiation. Moreover, other factors like presence of manganese sulfide (MnS) inclusions and improper material had also contributed towards crack propagation and final fracture.