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Animals ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 171
Author(s):  
Samantha Zurlinden ◽  
Stephany Spano ◽  
Emily Griffith ◽  
Sara Bennett

Excessive barking is a major source of noise pollution in dog kennels and negatively impacts welfare. Because resources are often limited, minimizing barking in the simplest and most easily implementable way is imperative. This pilot study implemented a Quiet Kennel Exercise (QKE) that utilized classical counterconditioning to change the dogs’ negative emotional state (which can lead to barking) to a more positive emotional state. Therefore, barking motivation is reduced, so barking should decrease. This study aims to show proof of concept that decreasing barking through classical counterconditioning is effective. It was conducted in one ward of day-time boarding kennels at North Carolina State University College of Veterinary Medicine. Data was collected three times per day and included decibel readings, number of dogs present, and number of dogs barking during a 5-day initial baseline and 10-day intervention period. During baseline, people passing through the ward acted as they normally would. During intervention, passersby were asked to simply toss each dog a treat regardless of the dogs’ behaviors in the kennel. Descriptive results show improvement in maximum level of barking after QKE, fewer dogs barking over time, dogs barking less each time, and the most improvement noted in the afternoon.


Author(s):  
Dan Halperin ◽  
Sariel Har-Peled ◽  
Kurt Mehlhorn ◽  
Eunjin Oh ◽  
Micha Sharir

PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262140
Author(s):  
Ihsan Elahi Zaheer ◽  
Shafaqat Ali ◽  
Muhammad Hamzah Saleem ◽  
Hafiza Sana Yousaf ◽  
Afifa Malik ◽  
...  

Environmental contamination of chromium (Cr) has gained substantial consideration worldwide because of its high levels in the water and soil. A pot experiment using oil seed crop (rapeseed (Brassica napus L.)) grown under different levels of tannery wastewater (0, 33, 66 and 100%) in the soil using the foliar application of zinc (Zn) and iron (Fe)–lysine (lys) has been conducted. Results revealed that a considerable decline in the plant growth and biomass elevates with the addition of concentrations of tannery wastewater. Maximum decline in plant height, number of leaves, root length, fresh and dry biomass of root and leaves were recorded at the maximum level of tannery wastewater application (100%) compared to the plants grown without the addition of tannery wastewater (0%) in the soil. Similarly, contents of carotenoid and chlorophyll, gas exchange parameters and activities of various antioxidants (superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX)) were also reduced significantly (P < 0.05) with the increasing concentration of tannery wastewater (33, 66 and 100%) in the soil. In addition, a combined application of Zn and Fe-lys reduced the accumulation and uptake of toxic Cr, while boosting the uptake of essential micronutrients such as Zn and Fe in different tissues of the plants. Results concluded that exogenous application of micronutrients chelated with amino acid successfully mitigate Cr stress in B. napus. Under field conditions, supplementation with these micronutrient-chelated amino acids may be an effective method for alleviating metal stress in other essential seed crops.


2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ahmed Hassanein ◽  
Jamal Ali Al-Khasawneh ◽  
Hany Elzahar

Purpose Corporate managers spend on research and development (R&D) for reasons of growth and survival. However, they may be less willing to invest in R&D because of its long-term horizon, high failure rate and uncertain outcomes. This study aims to explore the extent to which managerial ownership influences R&D expenditure decisions. Design/methodology/approach Apart from the linear regression models, this study uses a semi-parametric quantile regression analysis for a sample of German non-financial firms throughout 2009–2018. Findings This study finds a nonmonotonic sensitivity of R&D spending to the level of managerial ownership over various quantiles of R&D distribution. That is, managerial ownership increases the expenditure on R&D at low R&D intensity firms. However, it decreases the expenditure on R&D at high R&D intensity firms. These results suggest the presence of a maximum level of R&D expenditure, after which owner-managers would be unwilling to spend on R&D. Practical implications The results confirm the importance of corporate ownership structure for firm R&D and innovation activities. It provides an implication for corporate policymakers to reform the corporate ownership structures to encourage corporate managers and owners to invest in R&D projects. Originality/value This study offers two distinct contributions study. First, it provides the first German shred of evidence on the nonlinear relationship between managerial ownership and R&D expenditure decisions by distinguishing between high and low R&D intensity firms. Second, unlike prior research, it uses a semi-parametric quantile regression analysis. This method is more efficient than least-squares estimators and produces robust estimators to heteroscedasticity of the residuals.


2022 ◽  
Vol 23 (1) ◽  
pp. 282-293
Author(s):  
Maryam Poostchi ◽  
Hamed Bagheri

The use of phthalates as a plasticizer in plasticized polyvinyl chloride (PVC) always poses the threat of migration of phthalates into the environment through medical equipment. Phthalates can be used with natural-based plasticizers, such as Epoxidized soybean oil (ESBO) known as phthalate’s scavenger and PVC stabilizers. PVC formulations were characterized by different combinations of di (2-ethylhexyl) phthalate (DEHP) 30-40% with 5% ESBO. PVC flexibility increased significantly in the presence of ESBO, without a change in strength (tensile test). The decrease of the Tg temperature by adding ESBO in Differential Scanning Calorimetry indicated that ESBO preserved DEHP in the polymer. Also, it was shown that the sterilization process with Ethylene Oxide, similar to ESBO, decreased the Tg of polymer. DEHP migration was evaluated at a maximum level to the environment using the Gas Chromatography test. Samples containing ESBO showed less hemolysis. ABSTRAK: Penggunaan phthalates sebagai plasticizer dalam plastik polyvinyl chloride (PVC) selalu menimbulkan ancaman penghijrahan phthalates ke alam sekitar melalui peralatan perubatan. Phthalates boleh digunakan dengan plasticizer berasaskan semula jadi, seperti minyak kacang soya Epoxidized (ESBO) yang dikenali sebagai pemulung phthalate dan penstabil PVC. Formulasi PVC dicirikan oleh kombinasi yang berbeza di (2-ethylhexyl) phthalate (DEHP) 30-40% dengan 5% ESBO. Fleksibiliti PVC meningkat dengan ketara di hadapan ESBO, tanpa perubahan kekuatan (ujian tegangan). Penurunan suhu Tg dengan menambahkan ESBO dalam Calorimetri Pengimbasan Berbeza menunjukkan bahawa ESBO mengekalkan DEHP dalam polimer. Juga, ditunjukkan bahawa proses pensterilan dengan Etilena Oksida, serupa dengan ESBO, menurunkan Tg polimer. Penghijrahan DEHP dinilai pada tahap maksimum ke lingkungan menggunakan uji Kromatografi Gas. Sampel yang mengandungi ESBO menunjukkan kurang hemolisis. 


2022 ◽  
Vol 2150 (1) ◽  
pp. 012017
Author(s):  
V A Mikula ◽  
G E Maslennikov ◽  
T F Bogatova

Abstract Simulation of erosion wear and design optimization have been performed for a convective gas cooler with a helical coil. Based on the results of simulation of the standard gas cooler design with a flat baffle used in Shell gasification-based combined cycle unit, it is concluded that the particle impact angle is the main factor determining the erosion maximum. To reduce erosion, it is necessary to install a structural element instead of the flat baffle to align the flow path of ash particles at the inlet to the gas cooler. The results of simulation for various baffle shapes show that a hemispherical baffle is optimal. The use of a hemispherical baffle plate made it possible to align the ash particle flow path at the inlet to the gas cooler channels and reduce the maximum level of erosion by a factor of almost 4 compared to the standard geometry of the baffle plate.


Author(s):  
V. A. Anzorov ◽  
◽  
Svetlana Vasilievna Moryakina ◽  

The article presents the results of studies on the influence of mountain hypoxia on the state of the students’ respiratory system. When exposed to oxygen deficiency, only the respiratory capacity of the lungs undergoes significant changes. For instance, the RC level in female students under the influence of hypoxia gradually increased in conditions of medium altitude, reaching the maximum value of 0.64 liters (P ˂ 0.05), and on the plain - 0.44 liters. The RC value in young men reached the highest value of 0.74 liters in mid-altitude conditions, and on the plains, it constitutes 0.56 liters. The highest respiration rate for young men of 18.2 movements per minute was noted at an altitude of 600 meters, and the lowest - 17.4 at an altitude of 170 m. The maximum level of respiratory capacity while inhaling in girls is 1.24 liters, detected at an altitude of 600 meters, and the minimum level of 1.18 liters is noted at 170 m. The value of respiratory capacity while exhaling among young men living in the Sharoi region increased to 2.32 liters, and for those from Grozny - 2.24 liters. The highest VC level in girls - 3.87 liters - was found in the middle mountains, and on the plains, it was 3.58 liters. The VC value in young men, gradually increasing, reaches the highest value under the conditions of the Sharoi region - 4.57 liters, and in Grozny it was 4.28.


2022 ◽  
Vol 354 ◽  
pp. 00067
Author(s):  
Marin Silviu Nan ◽  
Daniel Cosmin Vitan ◽  
Sorina Daniela Anotoiu ◽  
Cristian Aron

The paper approaches the theoretical and experimental analysis of the level of exhaust gas pollution in a protected nature environmental, located in the mountain area, for excavation a trench. Due to the legislative provisions prohibiting the use of explosives in the nature reservation or other protected nature environmental areas, the mechanized excavation solution remains the only viable option. Excavation the trench through the mechanized solution must be carried out, taking into account the maximum level of pollution with exhaust gases provided in the legislative norms. According to the geotechnical data, the rock composition to be excavated on the route will be of different hardness, which involves impactors of various powers to displace the rock, on the one hand, and on the other, different excavators and bulldozers for the handling the material resulted from excavation. The theoretical research required to solve the problem has several stages, of which we mention: choosing the correct mechanization solution for displacing the hard and very hard rock; determination of fuel consumption, and energy consumption, respectively, transformation of the energy consumed in the liquid fuel necessary for the tool driving engines, and which generate exhaust gases.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Emmanuel Kaboja Magna ◽  
Samuel Senyo Koranteng ◽  
Augustine Donkor ◽  
Christopher Gordon

Heavy metals (Pb, Cd, As, Mn, Fe, Zn, Cu, Ni, and Cr) are some of the most toxic elements that can bioaccumulate from sources linked to human activities, such as industry and agriculture. This study quantifies the concentrations of several heavy metals in caged tilapia found in Ghana’s Volta Basin and assesses the associated health risks. The levels of heavy metals in the tissues of Oreochromis niloticus from three cage farms (N = 52) were determined using Atomic Absorption Spectrometry (AAS). The implication for human health was assessed using several risk assessment techniques. Fe (50.11 ± 10.22 mg/kg) and Cr (0.31 ± 0.07 mg/kg) had the highest and lowest accumulated metal concentrations, respectively. Heavy metal concentrations in tilapia tissue from fish farms were ordered as follows: Fe > Mn > Zn > Ni > Cr (farm A), Fe > Zn > Ni > Mn (farm B), and Fe > Mn > Zn > Ni > Cr (farm C). All metals had an estimated daily intake (EDI) below the threshold, and mean differences between sample farms were not statistically significant. Similarly, the values of target hazard quotients (HQs) and hazard indices (HIs) were less than one. According to the risk assessment results, eating tilapia from farms posed no risk to human health. The presence of Mn, Fe, and Ni concentrations above the maximum level in the fish, on the other hand, suggests that they may affect fish health.


2021 ◽  
Vol 10 (20) ◽  
pp. 212-218
Author(s):  
Cecilia Ionela Tăban ◽  
Simona Oancea

The isotope radon (222Rn), an inert water-soluble gas that may contaminate water, represents a potential risk for human health, including cancer. The present study reports the evaluation of the 222Rn concentration in drinking-water samples collected in 2020 from 10 sources located in Sibiu County, as measured using the pulse ionization chamber. Values of 222Rn varied from 0.0549 to 37.4770 Bq/l, with an average of 4.586 Bq/l. These values were below the maximum level of 100 Bq/l recommended by WHO and EU Directive/Euratom. With the exception of the sample from groundwater, the others showed 222Rn values below the maximum level of 11.1 Bq/l, as recommended by US EPA. In the case of impermeable soils, this radionuclide floats inside the cracks until it reaches the atmospheric air, so it is harmful to human health both in water and in the air. Evaluation of radon in water, in particular from groundwater sources becomes essential for the management of remedial solutions.


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