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Nitrogen is the most important and widely applied nutrient in sweet pepper production as it improves vegetative growth as well as fruit production. Therefore, the present research was aimed to evaluate promising sweet pepper cultivars as a function of different nitrogen fertilizer levels for semi-arid conditions of Pakistan during 2018 and 2019. Four nitrogen levels (75, 100, 125 and 150 kgha−1) and three sweet pepper cultivars (Ganga, Winner and Savio) were adopted in this study. Vegetative growth as well yield attributes were found highest during the cropping season of 2019 as compared with 2018. Plant height, stem diameter, canopy diameter, fresh and dry biomass of sweet pepper enhanced by the increased application of nitrogen from 75 to 125 kgha−1. All the yield contributing traits including number of fruits per plant, fruit fresh weight per plant and fruit yield per hectare were found the highest with nitrogen application of 150 kgha−1. In most of the crop traits, application of 125 kg Nha−1 and 150 kg Nha−1 produced statistically similar results. Cultivars respond differently to the nitrogen application. Ganga and Savio behaved similarly in response to nitrogen application. They had a quadratic response to nitrogen application; maximum growth and yield were at 125 kg Nha−1 and then decreased at 150 kg Nha−1. In contrast, Winner showed a somewhat linear response to nitrogen application and maximum growth, biomass and yield were recorded at 150 kg Nha−1. Planting a pepper cultivar with improved nitrogen use efficiency can result in maximum yield in a semi-arid region. [ABSTRACT FROM AUTHOR]

Salinity is one of the major abiotic stresses that is deteriorating soil fertility and reducing essential nutrients acquisition by plants around the world. Among staple food, wheat can be a primary source of micronutrients like Fe and Zn. The saline/saline-sodic and calcareous soils are deficient in Fe and Zn. In these regards, the aim of present study was to screen out wheat genotypes which can efficiently utilize Fe and Zn in saline conditions. Therefore, ten wheat genotypes (i.e., Ujala-2016, Punjab-2011, Galaxy-2013, Faisalabad-2008, Anaj-2017, SARC-I, SARC-VIII, Lasani-2008, Sehar-2006 and Inqalab-91) were exposed to varying rates of Zn (0.2, 0.4 µM) and Fe (25, 50 µM) under saline and normal conditions in a solution culture experiment. Salinity was developed by using NaCl salt, while the sources of Zn and Fe were ZnSO4.7H2O and FeSO4.7H2O, respectively. The data of various wheat growth and ionic parameters including root/shoot dry weight, chlorophyll contents, Zn, Fe, K and Na concentration in root and shoot of wheat genotypes were recorded using standard procedures. The results showed that Fe and Zn application significantly (p ≤ 0.05) increased wheat plant growth under salt stress. Among tested genotypes, Faisalabad-2008 and Galaxy-2013 performed better under saline conditions with maximum biomass production, Zn, Fe and K absorption. Thus, these both genotypes were found to be good source for future wheat breeding programs or can be grown by farmers owing to efficient Fe and Zn utilization as a gateway toward the production of Fe and Zn biofortified wheat under saline conditions. [ABSTRACT FROM AUTHOR]

In this work, we present the temperature-sensing responses of poly (vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)], a ferroelectric material. This P(VDF-TrFE) was used to investigate its response within the temperature range of 30 to 60 °C. The impedance and capacitance responses were recorded for different temperature values using an LCR meter at variable frequencies, and the resulting measurements proved the high sensitivity of the proposed device. A comparative study was performed to find the best responsive P(VDF-TrFE) weight-percent solution for different temperature ranges. The sensor responded continuously and linearly with high sensitivity. [ABSTRACT FROM AUTHOR]

In this study, we explored the effect of salinity on cadmium (Cd) tolerance and phytoremediation potential of Acacia nilotica. Two-month-old uniform plants of A. nilotica were grown in pots contaminated with various levels of Cd (0, 5, 10, and 15 mg kg−1), NaCl (0%, 0.5%, 1.0% (hereafter referred as salinity), and all possible combinations of Cd + salinity for a period of six months. Results showed that shoot and root growth, biomass, tissue water content and chlorophyll (chl a, chl b, and total chl a+b) contents decreased more in response to salinity and combination of Cd + salinity compared to Cd alone. Shoot and root K concentrations significantly decreased with increasing soil Cd levels, whereas Na and Cl concentrations were not affected significantly. Shoot and root Cd concentrations, bioconcentration factor (BCF) and translocation factor (TF) increased with increasing soil Cd and Cd + salinity levels. At low level of salinity (0.5%), shoot and root Cd uptake enhanced, while it decreased at high level of salinity (1.0%). Due to Cd tolerance, high shoot biomass and shoot Cd uptake, this tree species has some potential for phytoremediation of Cd from the metal contaminated saline and nonsaline soils. [ABSTRACT FROM AUTHOR]

A field experiment was conducted under two natural field conditions at the Research Farm (normal soil) and Proka Farm (salt-affected soil) of The Institute of Soil and Environmental Sciences (ISES), University of Agriculture, Faisalabad, Pakistan, to evaluate the performance of 11 rice genotypes in normal and salt-affected conditions. The experiment was laid out in randomized complete block design (RCBD) with three replications. The gas exchange attributes were measured at vegetative stage whereas the grain and straw yields and the yield components were recorded at maturity. After harvesting, the ionic parameters including sodium (Na+) and potassium (K+) were determined. Afterward, grain quality in terms of length, width, milling recovery, broken fraction, and chalkiness was also determined for the selected genotypes. Salt-affected conditions adversely affected the physiology, yield, and quality of the tested genotypes. The genotypes KS-282 followed by Shaheen Basmati showed significantly higher photosynthetic rate, transpiration rate, and stomatal conductance under both normal and salt-affected conditions, whereas the genotypes 99404 followed by 99417 showed minimum values of gas exchange attributes. The grain and straw yields were the highest in the case of KS-282 at both sites, whereas the lowest grain and straw yields were observed in the case of 99440 followed by 99417 under both normal and salt-affected conditions. Regarding the quality attributes, Super Basmati produced longer grains but with higher broken fraction and lower milling recovery, whereas the reverse was observed in the case of KS-282. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate any ameliorative effects of bentonite (BN) against immuno-pathological alterations induced by dietary aflatoxin B1(AFB1) or ochratoxin A (OTA) in broiler chicks. In one experiment, AFB1(0.1, 0.2 or 0.6 mg/kg feed) was fed alone and par alley with bentonite clay (3.7 or 7.5 g/kg feed) to the broilers. In the second experiment, the broilers were given feed contaminated with OTA (0.15, 0.3 or 1.0 mg/kg feed) alone and in combination with bentonite clay (3.7, 7.5, or 15 g/kg feed). Experimental feedings were continued for 42 days. At various time points along the feeding schedule, immune system organ histologic status, as well as host humoral and cellular immune responses, were evaluated in all groups. The dietary addition of AFB1and OTA alone significantly reduced immune responses in the birds as assessed by histological changes in the bursa of Fabricius and thymus, antibody responses to SRBC,in-vivolympho-proliferative responses to Phytohemagglutinin-P (PHA-P) and, phagocytic functionin situ. The dietary addition of BN significantly ameliorated the immunotoxicity of 0.1 and 0.2 mg/kg dietary AFB1, however with a level of 0.6 mg AFB1/kg only partial amelioration was seen. The co-treatment of birds exposed to OTA with BN at all levels only partially alleviated deleterious effects on histology and immune responses. Taken together, the results here suggested to us that dietary addition of BN could help ameliorate AFB1-mediated immunotoxicities but could not afford such protection against OTA-induced immune damage. [ABSTRACT FROM AUTHOR]

The main objective of this research was to conduct a theoretical investigation into the antioxidant properties of chlorogenic acid. Calculations based on the density functional theory were performed using the B3LYP exchange-correlation functional and the 6-311G standard basis set to determine the theoretical parameters, such as bond dissociation enthalpy and spin density. H atom abstraction from −OH groups was the most representative reaction pathway chosen for this study. From these calculations, it was estimated that bond dissociation enthalpies of hydroxyl groups were in the order of 3’-OH > 4’-OH > 2-OH > 1-OH. Spin densities of O-atoms of free radicals formed (after the removal of H atoms) from the hydroxyl groups of aromatic rings were lower than that of hydroxyl groups of alicyclic rings. On the basis of the calculated results, H atom abstraction from −OH groups of aromatic ring should be the main mechanism for the antioxidant potential of chlorogenic acid. Moreover, a comparison of bond dissociation enthalpy values for different phenolic acid antioxidants showed that the chlorogenic acid is a potent antioxidant. This theoretical investigation might be helpful for the future applications of chlorogenic acid in the field of the pharmacy and food industries. [ABSTRACT FROM PUBLISHER]

Excess of exchangeable sodium (Na) in salt-affected soils causes ion toxicity and decrease in nutrient uptake by plants, particularly potassium (K). A number of studies have been conducted to investigate the effect of K-fertilization on plant growth under sodic and saline-sodic conditions but the results are much diverse to process for concrete recommendations. To explore the possible reasons, it was hypothesized that Na applied as NaCl to produce salinity/sodicity in the soil may release non-exchangeable K, minimizing the effect of K-fertilization. Incubation studies were conducted for 2, 4 and 6 days in the light (sandy loam) and heavy (clay loam) textured soils producing two saline/sodic levels, i.e. 20 and 30 sodium adsorption ratio (SAR) along with control (SAR 3). Potassium fertilizer applied was calculated according to 40 (general recommendations based on soil-nutrient status), 80 and 160 kg K ha−1. Interestingly, it was observed that addition of NaCl possibly released non-exchangeable K from the soil minerals and increased the K concentration in soil solution. Total K release was more in heavy textured soil but initial release was more in light textured soil. This release may eliminate the effect of K-fertilization applied under salt stress induced by NaCl. Therefore, it is suggested that while studying Na–K interaction in salt-affected soils, NaCl should be avoided to produce salinity, and naturally occurring saline-sodic soils may be used. Soil Na–K interaction studies including ameliorating effect of K under sodic or saline-sodic conditions should be conducted carefully considering the above-stated argument. [ABSTRACT FROM PUBLISHER]

Construction is a dynamic industry that requires continuous focus on academic curriculum to meet the current workforce demands. Educational institutions that are responsible for developing undergraduate students require a strategic plan to adequately prepare future construction managers to be able to better manage the ever-increasing complexity of the construction industry. This paper investigates the most important skills that today’s construction industry requires from graduating construction management students. This research examines a skill set determined by an initial preliminary survey. This skill set was then addressed through structured surveys sent to various industry stakeholders in order to identify the key skills desired by the industry from today’s graduating construction management students. The significance of the study is it identifies the key knowledge areas; personal and professional attributes; skills; and expertise that academic curriculums in construction management programs need to focus on in order to adequately prepare graduating students entering today’s modern and complex construction industry. The study concludes that knowledge of health and safety regulations, interpreting contract documents, listening ability/ giving attention to details, knowledge of building codes and regulations, and time management are the five most important skills desirable in a new hire in construction management. [ABSTRACT FROM AUTHOR]

This article presents a space vector pulse width modulation based three-phase four-switch inverter for the sensor-less control of a three-phase permanent-magnet synchronous motor (PMSM). The PMSM was modeled in MATLAB SIMULINK using the dynamic model to extract signals required for the sensor-less control. The calculation of time for gate signals of the switches in the four-switch three-phase inverter has been explained in detail and implemented using the artificial neural networks. The ANN based SVPWM block takes reference voltage, frequency and modulation index as commands and provides three-phase voltages with variable frequency. An ANN based speed and position estimator was also implemented for the PMSM to eliminate mechanical sensors. The proposed system was implemented using the Texas Instruments' TMS320F2812 development kit and the National Instruments data acquisition module USB-6259. The results have been presented for the permanent magnet synchronous motor drive in under-modulation region. [ABSTRACT FROM AUTHOR]

Soft starters are used in electrical drives for the smooth starting of blowers, fans, mixers, crushers, grinders, and pumps, as well as in many other modern industrial applications. This article presents a soft starter that reduces energy losses during the start-up process of an induction motor. A sensor-less technique has been used to enhance the response of the system. The artificial neural networks, used in the soft starter, have been compared for the estimation of different parameters. The adaptive neuro fuzzy inference system has been developed to control the speed and torque of the motor with the constraint of “reduction in energy losses” during the start-up process. A neural network implements the feedback estimator, thus eliminating the need for slow mechanical sensors, while the adaptive neuro fuzzy inference system with the help of artificial neural network estimators adjusts the firing angles of the thyristors (of an AC voltage controller) under different loading conditions. The control system has been implemented using a TMS320F2812 (Texas Instruments, Texas, USA) processor. The presented approach can be employed for both the off-line and on-line trainings and, hence, can solve the problem of on-line computation of firing angles. [ABSTRACT FROM AUTHOR]

The genotypic differences regarding Na+ accumulation and transport in plants along with the physiological response to improve salt tolerance were studied in bread wheat genotypes. Four wheat genotypes; Kharchia-65, SARC-3, S-9476, and S-8189 were grown under salt stress (75 and 150 mM NaCl) in nutrient solution with five replications. Shoot dry weight, relative growth rate (RGR), chlorophyll index, leaf water relations, Na+ content, and transport in plants were measured. The increase in NaCl stress decreased all growth parameters; however, variations were observed among genotypes. Kharchia-65, S-9476, and SARC-3 had better growth and water relations compared with the salt-sensitive genotype S-8189. The low rate of Na+ transport and better ability to restrict Na+ in the root was the main reason for genetic variation among different genotypes, especially when growth characteristics did not vary significantly under salt stress. Na+ partition was also recorded in the wheat genotypes, since salt-sensitive genotypes had higher Na+ accumulation in shoot while this was reversed in tolerant ones. The differences in root Na+ were not significant among all genotypes. [ABSTRACT FROM AUTHOR]

This study reports the relationship of the leaf ionic composition with the grain yield and yield components of wheat in response to salinity x sodicity and salinity alone. The study was conducted in soil culture in pots with three treatments including control (ECe 2.6 dS m- 1 and SAR 4.53), salinity (ECe 15 dS m- 1 and SAR 9.56), and salinity x sodicity (ECe 15 dS m- 1 and SAR 35). The soil was treated before being put in the pots and the pots were arranged in a completely randomized factorial arrangement with five replications. The seeds of three wheat genotypes were sown directly in the pots and the study was continued till the crop maturity. At booting stage, the leaf second to the flag leaf of each plant was collected and analyzed for sodium (Na+), potassium (K+), and chloride (Cl-). At maturity, plants were harvested and data regarding grain yield and yield components were recorded. This study shows that salinity and sodicity in combination decreases the grain yield of wheat more than the salinity alone with a greater difference in the sensitive genotype. This study also shows that as for salinity, the maintenance of lower Na+ and higher K+ concentrations and higher K+: Na+ ratio in the leaves relates positively with the better development of different yield components and higher grain yield in saline sodic soil conditions. Although, the leaf Cl- concentration was increased significantly by salinity as well as salinity x sodicity and would have affected the growth and yield, yet it does not seem to determine the genotypic tolerance or sensitivity to either salinity or salinity x sodicity. [ABSTRACT FROM AUTHOR]