230 research outputs found

    Prevalence And Risk Factors Of Job Strain Among Laboratory Technicians In Hospital Universiti Sains Malaysia.

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    Several sources of job stress exist. Some of these stressors are intrinsic to the job,while some are related to psychosocial and other factors

    Rhizosphere dynamics of inoculated cyanobacteria and their growth-promoting role in rice crop

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    Nitrogen fixing cyanobacteria are the predominant flora in waterlogged paddy fields which contribute significantly towards nitrogen budgeting in these ecosystems. Their establishment and role in plant growth promotion and soil microbial activity is poorly known. Under greenhouse conditions, pots were inoculated with one of a set of twenty cyanobacterial strains isolated from the rhizosphere of diverse rice and wheat varieties. Several strains established in the soil and persisted up to the harvest stage in soil and roots, significantly enhancing soil microbial biomass carbon, available nitrogen, and related soil microbiological parameters, and increased grain yields and grain weight. This can help in selecting promising strains for developing carrier-based inoculants to promote the growth of crop and soil microflora, leading to enhanced soil fertility and crop yields

    Physiological and metabolic responses in broccoli plants fertilized with green manure

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    Grasses and legumes affect differently the amount of N in the soil over time, mainly due to the differences in the chemical characteristics of its mass. Changes in the availability of N influence the absorption and assimilation of N, which will influence physiological processes in the plants. The objective of this paper is to evaluate the changes in gas exchange, chlorophyll fluorescence and biochemical activity in leaves of broccoli grown under different green manure amendments. The experiment was designed in a complete randomized block design, using the mass of jack bean (JB) and millet (M) pure and in mixtures and one control, totaling six treatments: Control, 100JB, 75JB25M, 50JB50M, 25JB75M, 100M, with four replicates. The canopy area, N content, gas exchange, and biochemical analyzes were evaluated on the broccoli index leaf 40 days after broccoli transplantation. The higher ratio of jack bean, the higher the canopy area, the N content and the amino acid, protein and malate content, and lower starch content, possibly due to the higher N mineralization in this green manure.Grasses and legumes affect differently the amount of N in the soil over time, mainly due to the differences in the chemical characteristics of its mass. Changes in the availability of N influence the absorption and assimilation of N, which will influence physiological processes in the plants. The objective of this paper is to evaluate the changes in gas exchange, chlorophyll fluorescence and biochemical activity in leaves of broccoli grown under different green manure amendments. The experiment was designed in a complete randomized block design, using the mass of jack bean (JB) and millet (M) pure and in mixtures and one control, totaling six treatments: Control, 100JB, 75JB25M, 50JB50M, 25JB75M, 100M, with four replicates. The canopy area, N content, gas exchange, and biochemical analyzes were evaluated on the broccoli index leaf 40 days after broccoli transplantation. The higher ratio of jack bean, the higher the canopy area, the N content and the amino acid, protein and malate content, and lower starch content, possibly due to the higher N mineralization in this green manure

    Status report on emerging photovoltaics

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    \ua9 2023 Society of Photo-Optical Instrumentation Engineers (SPIE).This report provides a snapshot of emerging photovoltaic (PV) technologies. It consists of concise contributions from experts in a wide range of fields including silicon, thin film, III-V, perovskite, organic, and dye-sensitized PVs. Strategies for exceeding the detailed balance limit and for light managing are presented, followed by a section detailing key applications and commercialization pathways. A section on sustainability then discusses the need for minimization of the environmental footprint in PV manufacturing and recycling. The report concludes with a perspective based on broad survey questions presented to the contributing authors regarding the needs and future evolution of PV

    Influenza Virus A Infection of Human Monocyte and Macrophage Subpopulations Reveals Increased Susceptibility Associated with Cell Differentiation

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    Influenza virus infection accounts for significant morbidity and mortality world-wide. Interactions of the virus with host cells, particularly those of the macrophage lineage, are thought to contribute to various pathological changes associated with poor patient outcome. Development of new strategies to treat disease therefore requires a detailed understanding of the impact of virus infection upon cellular responses. Here we report that human blood-derived monocytes could be readily infected with the H3N2 influenza virus A/Udorn/72 (Udorn), irrespective of their phenotype (CD14++/CD16−, CD14++/CD16+ or CD14dimCD16++), as determined by multi-colour flow cytometry for viral haemagglutinin (HA) expression and cell surface markers 8–16 hours post infection. Monocytes are relatively resistant to influenza-induced cell death early in infection, as approximately 20% of cells showed influenza-induced caspase-dependent apoptosis. Infection of monocytes with Udorn also induced the release of IL-6, IL-8, TNFα and IP-10, suggesting that NS1 protein of Udorn does not (effectively) inhibit this host defence response in human monocytes. Comparative analysis of human monocyte-derived macrophages (Mph) demonstrated greater susceptibility to human influenza virus than monocytes, with the majority of both pro-inflammatory Mph1 and anti-inflammatory/regulatory Mph2 cells expressing viral HA after infection with Udorn. Influenza infection of macrophages also induced cytokine and chemokine production. However, both Mph1 and Mph2 phenotypes released comparable amounts of TNFα, IL-12p40 and IP-10 after infection with H3N2, in marked contrast to differential responses to LPS-stimulation. In addition, we found that influenza virus infection augmented the capacity of poorly phagocytic Mph1 cells to phagocytose apoptotic cells by a mechanism that was independent of either IL-10 or the Mer receptor tyrosine kinase/Protein S pathway. In summary, our data reveal that influenza virus infection of human macrophages causes functional alterations that may impact on the process of resolution of inflammation, with implications for viral clearance and lung pathology

    CPP-ZFN: A potential DNA-targeting anti-malarial drug

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    <p>Abstract</p> <p>Background</p> <p>Multidrug-resistant <it>Plasmodium </it>is of major concern today. Effective vaccines or successful applications of RNAi-based strategies for the treatment of malaria are currently unavailable. An unexplored area in the field of malaria research is the development of DNA-targeting drugs that can specifically interact with parasitic DNA and introduce deleterious changes, leading to loss of vital genome function and parasite death.</p> <p>Presentation of the hypothesis</p> <p>Advances in the development of zinc finger nuclease (ZFN) with engineered DNA recognition domains allow us to design and develop nuclease of high target sequence specificity with a mega recognition site that typically occurs only once in the genome. Moreover, cell-penetrating peptides (CPP) can cross the cell plasma membrane and deliver conjugated protein, nucleic acid, or any other cargo to the cytoplasm, nucleus, or mitochondria. This article proposes that a drug from the combination of the CPP and ZFN systems can effectively enter the intracellular parasite, introduce deleterious changes in its genome, and eliminate the parasite from the infected cells.</p> <p>Testing the hypothesis</p> <p>Availability of a DNA-binding motif for more than 45 triplets and its modular nature, with freedom to change number of fingers in a ZFN, makes development of customized ZFN against diverse target DNA sequence of any gene feasible. Since the <it>Plasmodium </it>genome is highly AT rich, there is considerable sequence site diversity even for the structurally and functionally conserved enzymes between <it>Plasmodium </it>and humans. CPP can be used to deliver ZFN to the intracellular nucleus of the parasite. Signal-peptide-based heterologous protein translocation to <it>Plasmodium</it>-infected RBCs (iRBCs) and different <it>Plasmodium </it>organelles have been achieved. With successful fusion of CPP with mitochondrial- and nuclear-targeting peptides, fusion of CPP with 1 more <it>Plasmodium </it>cell membrane translocation peptide seems achievable.</p> <p>Implications of the hypothesis</p> <p>Targeting of the <it>Plasmodium </it>genome using ZFN has great potential for the development of anti-malarial drugs. It allows the development of a single drug against all malarial infections, including multidrug-resistant strains. Availability of multiple ZFN target sites in a single gene will provide alternative drug target sites to combat the development of resistance in the future.</p

    Measurement of Λ4H\rm ^4_{\Lambda}H and Λ4He\rm ^4_{\Lambda}He binding energy in Au+Au collisions at sNN\sqrt{s_\mathrm{NN}} = 3 GeV

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    Measurements of mass and Λ\Lambda binding energy of Λ4H\rm ^4_{\Lambda}H and Λ4He\rm ^4_{\Lambda}He in Au+Au collisions at sNN=3\sqrt{s_{_{\rm NN}}}=3 GeV are presented, with an aim to address the charge symmetry breaking (CSB) problem in hypernuclei systems with atomic number A = 4. The Λ\Lambda binding energies are measured to be 2.22±0.06(stat.)±0.14(syst.)\rm 2.22\pm0.06(stat.) \pm0.14(syst.) MeV and 2.38±0.13(stat.)±0.12(syst.)\rm 2.38\pm0.13(stat.) \pm0.12(syst.) MeV for Λ4H\rm ^4_{\Lambda}H and Λ4He\rm ^4_{\Lambda}He, respectively. The measured Λ\Lambda binding-energy difference is 0.16±0.14(stat.)±0.10(syst.)\rm 0.16\pm0.14(stat.)\pm0.10(syst.) MeV for ground states. Combined with the γ\gamma-ray transition energies, the binding-energy difference for excited states is 0.16±0.14(stat.)±0.10(syst.)\rm -0.16\pm0.14(stat.)\pm0.10(syst.) MeV, which is negative and comparable to the value of the ground states within uncertainties. These new measurements on the Λ\Lambda binding-energy difference in A = 4 hypernuclei systems are consistent with the theoretical calculations that result in ΔBΛ4(1exc+)ΔBΛ4(0g.s.+)<0\rm \Delta B_{\Lambda}^4(1_{exc}^{+})\approx -\Delta B_{\Lambda}^4(0_{g.s.}^{+})<0 and present a new method for the study of CSB effect using relativistic heavy-ion collisions.Comment: 8 pages, 5 figure

    Measurement of electrons from open heavy-flavor hadron decays in Au+Au collisions at sNN=200\sqrt{s_{\rm NN}}=200 GeV with the STAR detector

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    We report a new measurement of the production of electrons from open heavy-flavor hadron decays (HFEs) at mid-rapidity (y<|y|< 0.7) in Au+Au collisions at sNN=200\sqrt{s_{\rm NN}}=200 GeV. Invariant yields of HFEs are measured for the transverse momentum range of 3.5<pT<93.5 < p_{\rm T} < 9 GeV/cc in various configurations of the collision geometry. The HFE yields in head-on Au+Au collisions are suppressed by approximately a factor of 2 compared to that in pp+pp collisions scaled by the average number of binary collisions, indicating strong interactions between heavy quarks and the hot and dense medium created in heavy-ion collisions. Comparison of these results with models provides additional tests of theoretical calculations of heavy quark energy loss in the quark-gluon plasma

    Elliptic Flow of Heavy-Flavor Decay Electrons in Au+Au Collisions at sNN\sqrt{s_{_{\rm NN}}} = 27 and 54.4 GeV at RHIC

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    We report on new measurements of elliptic flow (v2v_2) of electrons from heavy-flavor hadron decays at mid-rapidity (y<0.8|y|<0.8) in Au+Au collisions at sNN\sqrt{s_{_{\rm NN}}} = 27 and 54.4 GeV from the STAR experiment. Heavy-flavor decay electrons (eHFe^{\rm HF}) in Au+Au collisions at sNN\sqrt{s_{_{\rm NN}}} = 54.4 GeV exhibit a non-zero v2v_2 in the transverse momentum (pTp_{\rm T}) region of pT<p_{\rm T}< 2 GeV/cc with the magnitude comparable to that at sNN=200\sqrt{s_{_{\rm NN}}}=200 GeV. The measured eHFe^{\rm HF} v2v_2 at 54.4 GeV is also consistent with the expectation of their parent charm hadron v2v_2 following number-of-constituent-quark scaling as other light and strange flavor hadrons at this energy. These suggest that charm quarks gain significant collectivity through the evolution of the QCD medium and may reach local thermal equilibrium in Au+Au collisions at sNN=54.4\sqrt{s_{_{\rm NN}}}=54.4 GeV. The measured eHFe^{\rm HF} v2v_2 in Au+Au collisions at sNN=\sqrt{s_{_{\rm NN}}}= 27 GeV is consistent with zero within large uncertainties. The energy dependence of v2v_2 for different flavor particles (π,ϕ,D0/eHF\pi,\phi,D^{0}/e^{\rm HF}) shows an indication of quark mass hierarchy in reaching thermalization in high-energy nuclear collisions.Comment: 12 pages, 7 figures, 1 tabl

    Event-by-event correlations between Λ\Lambda (Λˉ\bar{\Lambda}) hyperon global polarization and handedness with charged hadron azimuthal separation in Au+Au collisions at sNN=27 GeV\sqrt{s_{\text{NN}}} = 27 \text{ GeV} from STAR

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    Global polarizations (PP) of Λ\Lambda (Λˉ\bar{\Lambda}) hyperons have been observed in non-central heavy-ion collisions. The strong magnetic field primarily created by the spectator protons in such collisions would split the Λ\Lambda and Λˉ\bar{\Lambda} global polarizations (ΔP=PΛPΛˉ<0\Delta P = P_{\Lambda} - P_{\bar{\Lambda}} < 0). Additionally, quantum chromodynamics (QCD) predicts topological charge fluctuations in vacuum, resulting in a chirality imbalance or parity violation in a local domain. This would give rise to an imbalance (Δn=NLNRNL+NR0\Delta n = \frac{N_{\text{L}} - N_{\text{R}}}{\langle N_{\text{L}} + N_{\text{R}} \rangle} \neq 0) between left- and right-handed Λ\Lambda (Λˉ\bar{\Lambda}) as well as a charge separation along the magnetic field, referred to as the chiral magnetic effect (CME). This charge separation can be characterized by the parity-even azimuthal correlator (Δγ\Delta\gamma) and parity-odd azimuthal harmonic observable (Δa1\Delta a_{1}). Measurements of ΔP\Delta P, Δγ\Delta\gamma, and Δa1\Delta a_{1} have not led to definitive conclusions concerning the CME or the magnetic field, and Δn\Delta n has not been measured previously. Correlations among these observables may reveal new insights. This paper reports measurements of correlation between Δn\Delta n and Δa1\Delta a_{1}, which is sensitive to chirality fluctuations, and correlation between ΔP\Delta P and Δγ\Delta\gamma sensitive to magnetic field in Au+Au collisions at 27 GeV. For both measurements, no correlations have been observed beyond statistical fluctuations.Comment: 10 pages, 10 figures; paper from the STAR Collaboratio
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