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1.
J Hazard Mater ; 466: 133543, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38262318

ABSTRACT

The prevalence of organophosphate esters (OPEs) in the global environment is increasing, which aligns with the decline in the usage of polybrominated diphenyl ethers (PBDEs). PBDEs, a category of flame retardants, were banned and classified as persistent organic pollutants (POPs) through the Stockholm Convention due to their toxic and persistent properties. Despite a lack of comprehensive understanding of their ecological and health consequences, OPEs were adopted as replacements for PBDEs. This research aims to offer a comparative assessment of PBDEs and OPEs in various domains, specifically focusing on their persistence, bioaccumulation, and toxicity (PBT) properties. This study explored physicochemical properties (such as molecular weight, octanol-water partition coefficient, octanol-air partition coefficient, Henry's law constant, and vapor pressures), environmental behaviors, global concentrations in environmental matrices (air, water, and soil), toxicities, bioaccumulation, and trophic transfer mechanisms of both groups of compounds. Based on the comparison and analysis of environmental and toxicological data, we evaluate whether OPEs represent another instance of regrettable substitution and global contamination as much as PBDEs. Our findings indicate that the physical and chemical characteristics, environmental behaviors, and global concentrations of PBDEs and OPEs, are similar and overlap in many instances. Notably, OPE concentrations have even surged by orders of several magnitude compared to PBDEs in certain pristine regions like the Arctic and Antarctic, implying long-range transport. In many instances, air and water concentrations of OPEs have been increased than PBDEs. While the bioaccumulation factors (BAFs) of PBDEs (ranging from 4.8 to 7.5) are slightly elevated compared to OPEs (-0.5 to 5.36) in aquatic environments, both groups of compounds exhibit BAF values beyond the threshold of 5000 L/kg (log10 BAF > 3.7). Similarly, the trophic magnification factors (TMFs) for PBDEs (ranging from 0.39 to 4.44) slightly surpass those for OPEs (ranging from 1.06 to 3.5) in all cases. Metabolic biotransformation rates (LogKM) and hydrophobicity are potentially major factors deciding their trophic magnification potential. However, many compounds of PBDEs and OPEs show TMF values higher than 1, indicating biomagnification potential. Collectively, all data suggest that PBDEs and OPEs have the potential to bioaccumulate and transfer through the food chain. OPEs and PBDEs present a myriad of toxicity endpoints, with notable overlaps encompassing reproductive issues, oxidative stress, developmental defects, liver dysfunction, DNA damage, neurological toxicity, reproductive anomalies, carcinogenic effects, and behavior changes. Based on our investigation and comparative analysis, we conclude that substituting PBDEs with OPEs is regrettable based on PBT properties, underscoring the urgency for policy reforms and effective management strategies. Addressing this predicament before an exacerbation of global contamination is imperative.


Subject(s)
Flame Retardants , Halogenated Diphenyl Ethers , Halogenated Diphenyl Ethers/toxicity , Halogenated Diphenyl Ethers/analysis , Environmental Monitoring , Organophosphates/analysis , Water/analysis , Flame Retardants/toxicity , Flame Retardants/analysis , Octanols , Esters/toxicity
2.
Psychol Res Behav Manag ; 15: 965-976, 2022.
Article in English | MEDLINE | ID: mdl-35480712

ABSTRACT

The purpose of this paper is to develop a theoretical framework for testing the perceived organizational support (POS)-employee performance relationship with a mediating effect of intrinsic motivation. To combine the concepts from perceived organizational support (POS) and employee performance, secondary data have been collected from different research papers to provide a literature-based analysis. The present study found positive relationships between POS, intrinsic motivation, and employees' performance. The study further realized the intrinsic motivation as a potential mediator between POS and performance relationship. From this framework, numerous areas of research can be pursued to be used to research and practice human resource management. The theoretical framework which is developed in this paper is based upon literature that can be proved empirically. To improve theory, research, and practice in the field of human resource management, this paper conceptualizes the concept of POS through the means of internal support.

3.
PLoS One ; 16(10): e0257951, 2021.
Article in English | MEDLINE | ID: mdl-34648523

ABSTRACT

Loquat [Eriobotrya japonica (Thunb.) Lindl.] is an important fruit crop in Pakistan; however, a constant decline in its production is noted due biotic and abiotic stresses, particularly disease infestation. Fungal pathogens are the major disease-causing agents; therefore, their identification is necessary for devising management options. This study explored Taxila, Wah-Cantt, Tret, Chatar, Murree, Kalar-Kahar, Choa-Saidan-Shah and Khan-Pur districts in the Punjab and Khyber Paktoon Khawa (KPK) provinces of Pakistan to explore the diversity of fungal pathogens associated with loquat. The samples were collected from these districts and their microscopic characterizations were accomplished for reliable identification. Alternaria alternata, Curvularia lunata, Lasiodiplodia theobromae, Aspergilus flavis, Botrytis cinerea, Chaetomium globosum, Pestalotiopsis mangiferae and Phomopsis sp. were the fungal pathogens infesting loquat in the study area. The isolates of A. alternata and C. lunata were isolated from leaf spots and fruit rot, while the isolates of L. theobromae were associated with twig dieback. The remaining pathogens were allied with fruit rot. The nucleotide evidence of internal transcribed spacer (ITS) regions (ITS1, 5.8S, and ITS2) were computed from all the pathogens and submitted in the database of National Center for Biotechnology Information (NCBI). For multigene analysis, beta-tubulin (BT) gene and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) regions were explored for A. alternata and C. lunata isolates, respectively. The virulence scales of leaf spots, fruit rot, and twig dieback diseases of loquat were developed for the first time through this study. It is the first comprehensive study with morpho-molecular identification, and newly developed virulence scales of the fungal pathogens associated with loquat, which improves the understanding of these destructive diseases.


Subject(s)
Ascomycota/pathogenicity , Biodiversity , Crops, Agricultural/microbiology , Eriobotrya/microbiology , Mitosporic Fungi/pathogenicity , Plant Diseases/microbiology , Ascomycota/genetics , DNA, Fungal/genetics , Fruit/microbiology , Mitosporic Fungi/genetics , Pakistan , Phylogeny , Plant Leaves/microbiology , Virulence
4.
Sci Rep ; 11(1): 18416, 2021 09 16.
Article in English | MEDLINE | ID: mdl-34531439

ABSTRACT

Soil with heavy metals contamination, mainly lead (Pb), cadmium (Cd), and chromium (Cr) is a progressively worldwide alarming environmental problem. Recently, biochar has been used as a soil amendment to remediate contaminated soils, but little work has been done to compare with other organic amendments like compost. We investigated biochar and compost's comparative effect on Pb, Cd, and Cr immobilization in soil, photosynthesis, and growth of maize plants. Ten kg soil was placed in pots and were spiked with Pb, Cd, and Cr at concentrations 20, 10, 20 mg kg-1. The biochar and compost treatments included 0, 0.5, 1, 2, and 4% were separately applied to the soil. The crop from pots was harvested after 60 days. The results show that the highest reduction of AB-DTPA extractable Pb, Cd, and Cr in soil was 79%, 61% and 78% with 4% biochar, followed by 61%, 43% and 60% with 4% compost compared to the control, respectively. Similarly, the highest reduction in shoot Pb, Cd, and Cr concentration was 71%, 63% and 78%with 4% biochar, followed by 50%, 50% and 71% with 4% compost than the control, respectively. The maximum increase in shoot and dry root weight, total chlorophyll contents, and gas exchange characteristics were recorded with 4% biochar, followed by 4% compost than the control. The maximum increase in soil organic matter and total nitrogen (N) was recorded at 4% biochar application while available phosphorus and potassium in the soil at 4% compost application. It is concluded that both biochar and compost decreased heavy metals availability in the soil, reducing toxicity in the plant. However, biochar was most effective in reducing heavy metals content in soil and plant compared to compost. In the future, more low-cost, eco-friendly soil remediation methods should be developed for better soil health and plant productivity.

5.
Sci Rep ; 11(1): 9445, 2021 05 03.
Article in English | MEDLINE | ID: mdl-33941790

ABSTRACT

Bacterial spot, caused by a group of Xanthomonads (Xanthomonas spp.), is a devastating disease. It can adversely affect the Capsicum annum productivity. Scientists are working on the role of antioxidants to meet this challenge. However, research is lacking on the role of antioxidant enzymes and their isoforms in the non-compatible pathogen and host plant interaction and resistance mechanisms in capsicum varieties. The present study was conducted to ascertain the defensive role of antioxidant enzymes and their isoforms in chilli varieties Hybrid, Desi, Serrano, Padron, and Shehzadi against bacterial spot disease-induced Xanthomonas sp. The seedlings were inoculated with bacterial pathogen @ 107 CFU/mL, and samples were harvested after regular intervals of 24 h for 4 days followed by inoculation. Total plant proteins were extracted in phosphate buffer and quantified through Bradford assay. The crude protein extracts were analyzed through quantitative enzymatic assays in order to document activity levels of various antioxidant enzymes, including peroxidase (POD), Catalase (CAT), Ascorbate peroxidase (APX), and Superoxide dismutase (SOD). Moreover, the profiles appearance of these enzymes and their isoforms were determined using native polyacrylamide gel electrophoresis (PAGE) analysis. These enzymes exhibited maximum activity in Hybrid (HiR) cultivar followed by Desi (R), Serrano (S), Padron, and Shehzadi (HS). Both the number of isoforms and expression levels were higher in highly resistant cultivars compared to susceptible and highly susceptible cultivars. The induction of POD, CAT, and SOD occurs at the early stages of growth in resistant Capsicum cultivars. At the same time, APX seems to make the second line of antioxidant defense mechanisms. We found that modulating antioxidant enzymes and isoforms activity at the seedling stage was an important mechanism for mitigating plant growth inhibition in the resistant ones.


Subject(s)
Antioxidants/metabolism , Capsicum/microbiology , Oxidative Stress/physiology , Plant Diseases/microbiology , Stress, Physiological/physiology , Ascorbate Peroxidases/metabolism , Capsicum/growth & development , Catalase/metabolism , Hydrogen Peroxide/analysis , Peroxidase/metabolism , Plant Proteins/analysis , Protein Isoforms/metabolism , Superoxide Dismutase/metabolism , Xanthomonas/pathogenicity
6.
Article in English | MEDLINE | ID: mdl-31783526

ABSTRACT

This study aimed to examine the impact of the five-dimensional health care service quality (SQ) on patient behavioral consent (PBC). This study further explored the mediating role of patient satisfaction (PS) on the SQ-PBC relationship. A survey questionnaire was used to collect the data from public sector hospitals situated in Bahawalpur division, Punjab, Pakistan. We used confirmatory factor analysis (CFA) and structural equation modeling (SEM) to test the hypotheses. This study found positive and significant relationships between SQ and PBC, SQ and PS, and PS and PBC. Our results further revealed that PS partially mediates the relationship between SQ and PBC. Our study offers a comprehensive theoretical framework of several service quality attributes (SQs) affecting patient behavioral consent (PBC) and patient satisfaction (PS) in health care institutions. Testing these above relationships via a mediation approach is novel and contributed to the current study on service quality.


Subject(s)
Behavior , Hospitals, Public/standards , Patient Satisfaction/statistics & numerical data , Quality of Health Care/statistics & numerical data , Surveys and Questionnaires/standards , Adolescent , Adult , Environment , Female , Hospital Administration/standards , Humans , Informed Consent , Male , Middle Aged , Pakistan , Personnel, Hospital/standards , Professional-Patient Relations , Young Adult
7.
J Org Chem ; 84(19): 12542-12552, 2019 10 04.
Article in English | MEDLINE | ID: mdl-31462047

ABSTRACT

Enol ethers are formed by radical decarboxylation of α-alkoxy ß-phenylthio acids via the corresponding Barton esters. The phenylthio acids were usually made by the known regioselective reaction of α,ß-epoxy acids with PhSH in the presence of InCl3, followed by O-alkylation of the resulting alcohol. In one case, thiol addition to an α,ß-unsaturated ethoxymethyl ester was used.

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