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Author(s):  
Dermeval A. Furtado ◽  
Ladyanne R. Rodrigues ◽  
Valéria P. Rodrigues ◽  
Neila L. Ribeiro ◽  
Rafael C. Silva ◽  
...  

ABSTRACT The supply of salt water in the semiarid region is a recurrent practice, as there is a severe shortage of water for use in animal consumption. Thus, most of the times the water offered to the birds can contain salts above the recommended amount. The present study aimed to evaluate the production performance and morphometry of the organs of Japanese quails as they were supplied with drinking water with different concentrations of sodium chloride, while being maintained in comfort and under thermal stress. The birds received water with increasing electrical conductivity (1.5, 3.0, 4.5 and 6.0 dS m-1) and were kept in a climate chamber at thermoneutral air temperature (24 °C) and under thermal stress (32 °C), being distributed in a completely randomized design and 2 × 4 factorial scheme. Water electrical conductivities did not affect the performance of the birds, except for the weight of the gizzard, which showed an increasing linear effect as the electrical conductivities increased. At the stress temperature, there was reduction in feed intake, egg weight and mass, and in feed conversion per dozen eggs, but with no effect on the weights of the heart, liver and gizzard. Japanese quails in the production phase can consume water with electrical conductivity of up to 6.0 dS m-1, showing good production performance and without compromising organ morphometry.


Author(s):  
Aérica C. Nazareno ◽  
Iran J. O. da Silva ◽  
Eduardo F. Delgado ◽  
Miguel Machado ◽  
Luiz O. Pradella

ABSTRACT The inclusion of environmental enrichment in conventional broiler rearing can increase mobility, bone mass and muscle. This research aimed to evaluate the use of environmental enrichment in the rearing of broilers at different ages and its influence on performance, morphometry, yield and weight of the parts. It was used the completely randomized design in split-plot scheme, being the plots the treatments presence (T1) and absence (T2) of environmental enrichment and the subplots the broiler ages (1, 7, 14, 21, 28, 35 and 42 days), with 56 chicks in each treatment (T1 and T2). Data obtained were analyzed by the linear effect model of fixed effects and compared by Tukey’s test of means. The animals were raised in a controlled environment, divided into four boxes with dimensions: 1.5 × 1.0 × 0.7 m, containing rice straw bed. In T1 a ladder with a perch on top was used, distributed every 1.5 m2. Environmental enrichment used did not influence broiler’s zootechnical performance. Broilers’ morphometric properties, parts weight and body weight increased due to environmental enrichment and, improvement was observed in chicks rearing’s final phase. The environmental enrichment was beneficial for muscle and bone mass gain in the main commercial parts of the chicken carcass, in addition to reducing the allometric coefficient of the breasts in chickens.


2022 ◽  
Vol 9 ◽  
Author(s):  
Zahid Hussain ◽  
Bilal Mehmood ◽  
Muhammad Kaleem Khan ◽  
Raymondo Sandra Marcelline Tsimisaraka

Green growth is an exceptional strategy for sustainable development. It provides a pathway to combat environmental issues and the use of natural resources. This study investigates the effects of green technology and environmental factors on green growth in high-gross domestic product (GDP) countries from 2000 to 2020. In addition, it also probes the linear and nonlinear effects of GDP on green growth. To do so, we employ an advanced econometric approach, e.g., a cross-sectional autoregressive distributed lags estimator for long and short runs. The outcomes demonstrate that the linear effect of GDP is positive for green growth. On the contrary, the nonlinear effect of GDP has a negative magnitude for green growth. Besides, green technology substantially increases green growth. Energy consumption is found to be an important influencer, and it decreases green growth. Environmental factors such as emissions, according to the findings, also reduce green growth in the sample countries. It is worth noting that the joint effects of energy consumption and emissions deteriorate green growth in countries. Based on empirical findings, for policy makers, this study suggests that high-GDP countries should manage their economic and environmental activities in order to increase the amount of green growth that may protect the ecological environment.


2022 ◽  
Vol 43 (1) ◽  
pp. 179-196
Author(s):  
Janiquele Soares Silva Batista ◽  
◽  
Dorismar David Alves ◽  
João Paulo Sampaio Rigueira ◽  
Alfredo Acosta Backes ◽  
...  

The objective was to evaluate the qualitative and nutritional aspects of elephant grass cv. BRS capiaçu silage with increasing proportions of silk cotton. A completely randomized design was used with five (0, 15, 30, 45, and 60% on natural matter basis) different inclusion proportions of silk cotton to elephant grass silage and four repetitions. Silages were prepared in PVC minisilos and remained ensiled for 42 days. The inclusion of silk cotton resulted in a linear reduction in dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose, and indigestible neutral detergent fiber (iNDF) contents at 0.06, 0.30, 0.23, 0.20, and 0.09 percentage points for each 1% inclusion, respectively. There was an increasing linear effect of crude protein (CP) and total digestible nutrients (TDN), with an increase of 39.32 and 20.89% from the lowest to the highest inclusion of silk cotton to elephant grass cv. BRS capiaçu silage. Values of pH, gas losses (GL), effluent losses (EL), dry matter recovery (DMR), hemicellulose, and lignin were not influenced by the evaluated inclusion levels, showing estimated averages of 3.87, 1, 42%, 11.55kg t-1 natural matter, 97.36%, 19.30%, and 7.20%, respectively. An increasing linear effect was found for fraction a, c, effective degradability (ED) (2% and 5%) dry matter, with an increment of 0.05, 0.0005, and 0.11 percent points, respectively. There was a quadratic effect for fraction b, potential degradability (PD), ED (2%), with minimum points of 23.72%, 50.52%, (at 45% inclusion level) 39.69%, (at 15% inclusion level) respectively. The indigestible fraction (IF) had a quadratic effect with a maximum of 49.48% at the 45% inclusion level. The colonization time (CT) linearly reduced by 0.09 percentage points for each 1% inclusion evaluated. According to the parameters evaluated, the inclusion of up to 60% silk cotton improved nutritional aspects and nutritional value of elephant grass cv. BRS capiaçu silage.


2022 ◽  
Vol 9 ◽  
Author(s):  
Tianyi Qiu ◽  
Han Xiao ◽  
Vladimir Brusic

The COVID-19 pandemic of 2020–21 has been a major challenge to public health systems worldwide. Mathematical models of epidemic are useful tools for assessment of the situation and for providing decision-making support for relevant authorities. We developed and implemented SEIR(MH) model that extends the conventional SEIR model with parameters that define public lockdown (the level and start of lockdown) and the medical system capacity to contain patients. Comparative modeling of four regions in Europe that have similar population sizes and age structures, but different public health systems, was performed: Baden-Württemberg, Lombardy, Belgium, and Switzerland. Modeling suggests that the most effective measure for controlling epidemic is early lockdown (exponential effect), followed by the number of available hospital beds (linear effect if the capacity is insufficient, with diminishing returns when the capacity is sufficient). Dynamic management of lockdown levels is likely to produce better outcomes than strict lockdown.


2021 ◽  
Vol 39 (4 supplement) ◽  
pp. 1336-1345
Author(s):  
Abobaker Al.Al. HADOOD ◽  
◽  
Ridha Ali Mohamed BEN SALEH ◽  
Khaled AB EMGEG ◽  
◽  
...  

Tourism has become an information-intensive business that heavily relies on ICT to provide information and conduct transactions for consumers of touristic products and services. Thus, ICT infrastructure would play a major role in the development of the tourism sector. This paper aims to investigate the threshold effect of ICT infrastructure on tourism sector development in top10 African tourism destinations including ; Botswana, Egypt, Kenya, Morocco, Namibia, Rwanda, South Africa, Tanzania, Tunisia, Uganda. To do so, a double panel threshold regression model utilized over the period 2004 to 2017. The empirical results revealed a new perspective that there is a double-threshold effect of ICT infrastructure on the development of tourism sector, indicating a non-linear effect of ICT infrastructure on the development of tourism sector in top 10 African tourism destinations. More specifically, the empirical results reveal that ICT infrastructure weakly and positively derives the number of intentional tourism arrivals and international tourist receipts when the level of ICT infrastructure is less or equal to the first threshold, while it strongly and positively derives the number of intentional tourism arrivals and international tourist when the level of ICT infrastructure is less or equal to the first and second thresholds. Thus, this paper provides important implications for policy makers, in that maximizing the benefits from information technology in developing tourism sector can be achieved when its level between certain critical threshold values.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7595
Author(s):  
Abdulrahman M. Alhozaimy ◽  
Mshtaq Ahmed ◽  
Raja Rizwan Hussain ◽  
Abdulaziz Al-Negheimish

This paper investigates the effect of high ambient temperatures on the chloride threshold value for reinforced concrete (RC) structures. Two commonly available carbon steel rebars were investigated under four different exposure temperatures (20 °C (68 °F), 35 °C (95 °F), 50 °C (122 °F), and 65 °C (149 °C)) using environmental chambers at a constant relative humidity of 80%. For each temperature, six different levels of added chloride ions (0.00%, 0.15%, 0.30%, 0.60%, 0.90%, and 1.20% by weight of cement) were used to study the chloride threshold value. Corrosion initiation was detected by monitoring the corrosion potential and corrosion rate using electrochemical techniques. The water-soluble (free) and acid-soluble (total) chlorides were determined using potentiometric titration according to the relevant ASTM standards. The threshold chloride content for each exposure temperature was determined by analyzing the corrosion potential, corrosion rate, and chloride content of each specimen. The results showed that the chloride threshold values were significantly temperature-dependent. At temperatures of 20 °C (68 °F) and 35 °C (95 °F), the chloride threshold value (expressed as free chlorides) was approximately 0.95% by weight of cement. However, as the temperature increased to 50 °C (122 °F), the chloride threshold decreased significantly to approximately 0.70% by weight of cement. The reduction in the chloride threshold value became more dramatic at an exposure temperature of 65 °C (149 °F), decreasing to approximately 0.25% by weight of cement. The trends were similar for the rebars from the two sources, indicating that the rebar source had little influence on the chloride threshold value.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Oliver Grimm ◽  
Daan van Rooij ◽  
Asya Tshagharyan ◽  
Dilek Yildiz ◽  
Jan Leonards ◽  
...  

AbstractADHD is a neurodevelopmental disorder with a long trajectory into adulthood where it is often comorbid with depression, substance use disorder (SUD) or obesity. Previous studies described a dysregulated dopaminergic system, reflected by abnormal reward processing, both in ADHD as well as in depression, SUD or obesity. No study so far however tested systematically whether pathologies in the brain’s reward system explain the frequent comorbidity in adult ADHD. To test this, we acquired MRI scans from 137 participants probing the reward system by a monetary incentive delay task (MIDT) as well as assessing resting-state connectivity with ventral striatum as a seed mask. No differences were found between comorbid disorders, but a significant linear effect pointed toward less left intrastriatal connectivity in patients depending on the number of comorbidities. This points towards a neurobiologically impaired reward- and decision-making ability in patients with more comorbid disorders. This suggests that less intrastriatal connectivity parallels disorder severity but not disorder specificity, while MIDT abnormalities seem mainly to be driven by ADHD.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Matthew J. Pringle ◽  
Steven G. Bray ◽  
John O. Carter

Abstract Background Land clearing generates coarse woody debris (CWD), much of which ultimately becomes atmospheric CO2. Schemes for greenhouse gas accounting must consider the contribution from land clearing, but the timing of the contribution will have large uncertainty, due to a paucity of knowledge about the rate of CWD disappearance. To better understand above-ground CWD disappearance following a land clearing event—through the actions of microorganisms, invertebrates, wildfire, or deliberate burning—we combined statistical modelling with an archive of semi-quantitative observations (units of CWD %), made within Queensland, Australia. Results Using a generalised additive mixed-effects model (median absolute error = 14.7%), we found that CWD disappearance was strongly influenced by the: (i) number of years elapsed since clearing; (ii) clearing method; (iii) bioregion (effectively a climate-by-tree species interaction); and (iv) the number of times burned. Years-since-clearing had a strongly non-linear effect on the rate of CWD disappearance. The data suggested that disappearance was reverse-sigmoidal, with little change in CWD apparent for the first three years after clearing. In typical conditions for Queensland, the model predicted that it will take 38 years for 95% of CWD to disappear, following a land clearing event; however, accounting for uncertainty in the data and model, this value could be as few as 5 years, or > 100 years. In contrast, due to an assumption about the propensity of land managers to burn CWD, the official method used to assess Australia’s greenhouse gas emissions predicted that 95% of CWD will disappear in < 1 year. Conclusions In Queensland, the CWD generated by land clearing typically takes 38 years to disappear. This ultimately implies that a key assumption of Australia’s official greenhouse gas reporting—i.e. that 98% of CWD is burned soon after a clearing event—does not adequately account for delayed CO2 emissions.


2021 ◽  
Vol 173 ◽  
pp. 121107
Author(s):  
Canh Phuc Nguyen ◽  
Bach Nguyen ◽  
Bui Duy Tung ◽  
Thanh Dinh Su

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