In this paper, ZnO nanoparticles (NPs) having potent photocatalytic and antimicrobial activities have been synthesized by using the aloe vera plant extract. The ZnO NPs have been synthesized using
(
...Zn
(
CH
3
COO
)
2
·
2
H
2
O
)
(5, 10 and
50
mmol
kg
-
1
), at temperature
70
∘
C
and pH 11.5. The synthesized NPs were examined using UV–Visible, X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM) characterization techniques. TEM analysis confirms the synthesis of ZnO NPs with hexagonal, spherical, cylindrical and cuboidal shapes decorated under different concentrations of precursor metal salt. UV–Visible studies revealed that ZnO NPs have a wide energy band gap varying from 3.36 to 3.43 eV. The synthesized ZnO NPs were examined for the photocatalytic degradation of methyl orange dye which resulted in up to 95% degradation. ZnO NPs are also inspected for the antibacterial activity against
Bacillus subtilis
(MTCC 441),
Staphylococcus aureus
(MTCC 737) and
Escherichia coli
(MTCC 739) pathogenic bacteria.
•Specific conductance has been measured for surfactant–amino acid–water ternary system.•CMC and thermodynamic parameters have been evaluated for the studied system.•Effect of temperature and ...additives has been explored.•Hydrophobic and hydrophilic dehydration have been discussed in detail.•Different interactions occurring in such system have been explored from computed parameters.
Specific conductance of (0.3 to 3.0)mmol·kg−1 sodium dodecyl benzene sulfonate (SDBS) and (3.0 to 30.0)mmol·kg−1 dodecyltrimethylammonium bromide (DTAB) has been determined in water and in the presence of (0.01, 0.05 and 0.10)mol·kg−1 aqueous solution of glutamine/histidine/methionine at T=(293.15, 298.15, 303.15, 308.15 and 313.15)K. From the conductivity data, the critical micellar concentration (CMC) and thermodynamic parameters of micellization (ΔGmo,ΔHmo and ΔSmo) have been computed by applying the mass action model. Enthalpy–entropy compensation effect has also been observed. The effect of amino acid on the micellar properties of SDBS and DTAB depends upon their nature, concentration, as well as on temperature and has been used to study the interactions present in the micellar systems. There occurs a gradual increase in the value of CMC with temperature in case of SDBS while in case of DTAB, it passes through a broad minimum and then tends to increase with increase in temperature. Increase of amino acid concentration is found to decrease CMC in both the surfactants. The ΔGmo values are negative and the feasibility of the micellization is found to increase with rise in temperature. The magnitude of hydrophilic and hydrophobic dehydration determines whether the CMC values increase or decrease with rise in temperature.
This paper reports a large-scale synthesis of ZnO balls made of fluffy thin ZnO nanosheets by simple solution process at low-temperature of 65±2°C. The synthesized ZnO structures were characterized ...in detail in terms of their morphological, structural, optical and photocatalytic properties. The as-synthesized ZnO balls were utilized as an efficient photocatalysts for the photocatalytic degradation of methylene blue (MB) dye which exhibits almost complete degradation of MB within 70min under UV-light irradiation. The photocatalytic performances of as-synthesized ZnO balls are found to be better than the commercially available TiO2–UV-100.
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► Simply synthesized ZnO balls made of fluffy thin nanosheets were utilized for the photocatalytic degradation of methylene blue (MB) dye. ► Almost complete degradation of MB was observed within 70min under UV-light irradiation. ► The synthesized ZnO exhibits superior photocatalytic performance as compared to commercially available TiO2-UV-100 photocatalyst.
This paper reports a large-scale synthesis of ZnO balls made of fluffy thin ZnO nanosheets by simple solution process at low-temperature of 65±2°C. The synthesized ZnO structures were characterized in detail in terms of their morphological, structural, optical and photocatalytic properties. The detailed morphological characterizations, done by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), confirmed that the synthesized products are ZnO balls which are made by accumulation of hundreds of thin ZnO nanosheets. Interestingly, it is seen that the nanosheets are arranged in such a special fashion that they made ball-like morphologies. Detailed structural examinations revealed that of as-synthesized ZnO products are well-crystalline and possessing wurtzite hexagonal phase. The optical property, measured by UV–Visible spectroscopy, substantiated good optical properties for as-synthesized ZnO balls. The as-synthesized ZnO balls were utilized as an efficient photocatalysts for the photocatalytic degradation of methylene blue (MB) dye. Almost complete degradation of MB was observed in presence of ZnO balls composed of nanosheets within 70min under UV-light irradiation. By comparing the photocatalytic performance with commercially available TiO2–UV-100, it was observed that the synthesized ZnO balls exhibited superior photocatalytic performance as compared to TiO2–UV-100 photocatalyst.
Mercury is a highly toxic environmental pollutant; thus, there is an urgent need to develop new materials for its simultaneous detection and removal from water. In the present study, new oxidized ...cellulose-based materials, including their Schiff bases, were synthesized and investigated as a sensor–adsorbent for simple, rapid, highly selective, and simultaneous detection and removal of mercury Hg(II) ions. Cellulose was extracted from the pine needles, etherified, oxidized, and modified to Schiff base by reaction with l-lysine. The well-characterized cellulose Schiff base materials were used as a sensor–adsorbent for Hg(II) from aqueous solution. Hg(II) sensing was analysed with naked-eye detection and fluorescence spectroscopy. Schiff base having a decyl chain, C10–O–cell–HCN–Lys, was observed to be an efficient adsorbent with a very high maximum adsorption capacity of 258.75 mg g–1. The data were analyzed on the basis of various kinetic and isotherm models, and pseudo-second-order kinetics and Langmuir isotherm were followed for Hg(II) adsorption.
There are currently two tests for diagnosing latent tuberculosis infection (LTBI); TST and IGRA. However, it is still unclear that which one of these tests performs better in high TB-burden settings.
...1511 household contacts of pulmonary TB patients were enrolled to compare the performance of TST and IGRA for LTBI. At baseline all participant underwent testing for IGRA QuantiFERON-TB® Gold In-tube (QFT-GIT) assay and TST 2 tuberculin unit (TU), purified protein derivative (PPD), RT23, Staten Serum Institute (SSI), Copenhagen, Denmark. All the household contacts were followed-up for two years for incident TB cases.
Active TB was diagnosed in 76 household contacts at an incidence rate of 2.14 per 1000 person-years. Both, TST Hazard Ratio (HR): 1.14, 95% confidence interval (CI): 0.72-1.79, p = 0.57, as well as QFT-GIT assay (HR: 1.66, 95% CI: 0.97-2.84, p = 0.06) results at baseline were not significantly associated with subsequent development of active TB among household contacts of pulmonary TB patients.
Neither TST nor IGRA predicted subsequent development of active TB among household contacts of pulmonary TB patients during follow-up. However, keeping in view the cost, and other logistics, TST remains the most preferred method for LTBI diagnosis in resource-limited, high TB-burden settings.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In spite of its wide and beneficial pharmacological potential, resveratrol lags behind other compounds because of its comparatively less impressive pharmacokinetic profile. Resveratrol has very low ...oral bioavailability and, from a formulation perspective, it has low solubility in water, which leads to its poor absorption upon oral administration. Apart from low aqueous solubility, resveratrol has poor metabolic stability and instability at high pH, and is photosensitive. The pharmacokinetic and formulation‐related limitations of resveratrol can be controlled by entrapping the small resveratrol molecule inside highly water‐soluble poly(amidoamine) dendrimer nanostructures, which provide spherical architecture and polyvalency at the nanoscale level, thus leading to novel features. Dendrimer architecture is used to entrap resveratrol for enhancement of its solubility and stability in aqueous solution; they can be engineered to control pharmacokinetics and targeting for oral, mucosal, transdermal, or parenteral administration. Dendrimers have the potential to work as excipients with multifunctional capability by enhancing solubility, dissolution, stability, permeability, multiple drug/cosmetic entrapment, controlled delivery, bioavailability, and efficacy of drugs.
In the present work diethylenetriamine functionalized graphene oxide (DETA-GO) has been synthesized and its corrosion inhibition performance was evaluated in 1 M HCl for mild steel. The chemical ...structure of the synthesized DETA-GO was analyzed by FTIR and the morphology was studied using SEM, TEM, and FTIR. The corrosion inhibition behavior was studied using weight loss studies, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. DETA-GO behaved as an efficient corrosion inhibitor as evident from the results of the electrochemical analysis. Electrochemical studies showed that the inhibition efficiency of DETA-GO increased with the concentration and reached 92.67% at a concentration of 25 mg L
−1
. The inhibitor exhibits a mixed type nature with cathodic predominance. The protective film of the inhibitor over the mild steel surface was examined by SEM and FTIR-ATR studies. A computational study using DFT further supports the promising corrosion inhibition behavior of DETA-GO.
Electrochemical and surface studies of diethylenetriamine functionalized graphene oxide as a novel corrosion inhibitor for mild steel in hydrochloric acid solutions.
Short peptides have attracted significant attention from researchers in the past few years due to their easy design, synthesis and characterization, diverse functionalisation possibilities, low cost, ...possibility to make a large range of hierarchical nanostructures and most importantly their high biocompatibility and biodegradability. Generally, short peptides are also relatively more stable than their longer variants, non-immunogenic in nature and many of them self-assemble to provide an exciting range of nanostructures, including hydrogels. Thus, the development of short peptide-based hydrogels has become an area of intense investigation. Although these hydrogels have a water content of greater than 90%, they are surprisingly highly stable structures, and thus have been used for various biomedical applications, including cell therapeutics, drug delivery, tissue engineering and regeneration, contact lenses, biosensors, and wound healing, by different researchers. Herein, we review the progress of research in the rapidly expanding field of short to ultrashort peptide-based hydrogels and their possible applications. Special attention is paid to address and review this field with regard to the stability of peptide-based hydrogels, particularly to enzymatic degradation.
Short peptides have attracted much attention due to their easy synthesis, diverse functionalisation possibilities, low cost, possibility to make a large range of hierarchical nanostructures and most importantly their high biocompatibility and biodegradability.
Heat stress is one of the most stressful events in the life of livestock with harmful consequences for animal health, productivity and product quality. Ruminants, pigs and poultry are susceptible to ...heat stress due to their rapid metabolic rate and growth, high level of production, and species-specific characteristics such as rumen fermentation, sweating impairment, and skin insulation. Acute heat stress immediately before slaughter stimulates muscle glycogenolysis and can result in pale, soft and exudative (PSE) meat characterized by low water holding capacity (WHC). By contrast, animals subjected to chronic heat stress, have reduced muscle glycogen stores resulting in dark, firm and dry (DFD) meat with high ultimate pH and high WHC. Furthermore, heat stress leads to oxidative stress, lipid and protein oxidation, and reduced shelf life and food safety due to bacterial growth and shedding. This review discusses the scientific evidence regarding the effects of heat stress on livestock physiology and metabolism, and their consequences for meat quality and safety.
Tropical pyomyositis, a disease often seen in tropical countries, is characterised by suppuration within skeletal muscles, manifesting as single or multiple abscesses. The most common organism ...implicated is Staphylococcus aureus. In 20%–50% of cases there is a history of trauma to the affected muscles. Commonly involved muscles are quadriceps, glutei, pectoralis major, serratus anterior, biceps, iliopsoas, gastrocnemius, abdominal and spinal muscles. Early diagnosis is often missed because of lack of specific signs, unfamiliarity with the disease, atypical manifestations, and a wide range of differential diagnosis. Diagnostic techniques like ultrasound and computed tomography/magnetic resonance imaging are very useful in diagnosis. The diagnosis is confirmed either by biopsy or aspiration of pus from the affected muscles. The initial antibiotic of choice is cloxacillin. Incision and drainage are important components of management. Treatment for Gram negative or anaerobic organisms should be instituted, whenever indicated. Physicians should become more familiar with this potentially life threatening but curable infective disease entity.
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