Background & objectives: There is a paucity of data available on genetic biodiversity of Mycobacterium tuberculosis isolates from central India. The present study was carried out on isolates of M. ...tuberculosis cultured from diagnostic clinical samples of patients from Bhopal, central India, using spoligotyping as a method of molecular typing.
Methods: DNA was extracted from 340 isolates of M. tuberculosis from culture, confirmed as M. tuberculosis by molecular and biochemical methods and subjected to spoligotyping. The results were compared with the international SITVIT2 database.
Results: Sixty five different spoligo international type (SIT) patterns were observed. A total of 239 (70.3%) isolates could be clustered into 25 SITs. The Central Asian (CAS) and East African Indian (EAI) families were found to be the two major circulating families in this region. SIT26/CAS1_DEL was identified as the most predominant type, followed by SIT11/EAI3_IND and SIT288/CAS2. Forty (11.8%) unique (non-clustered) and 61 (17.9%) orphan isolates were identified in the study. There was no significant association of clustering with clinical and demographic characteristics of patients.
Interpretation & conclusions: Well established SITs were found to be predominant in our study. SIT26/CAS1_DEL was the most predominant type. However, the occurrence of a substantial number of orphan isolates may indicate the presence of active spatial and temporal evolutionary dynamics within the isolates of M. tuberculosis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Weeds are a major biotic constraint to the production of crops. Studies on the critical period of weed control (CPWC) consider the yield loss due to the presence of all weeds present in the crop ...cycle. The CPWC is the time interval between the critical timing of weed removal (CTWR) and the critical weed-free period (CWFP), and the weed presence before and after the extremes of CTWR and CWFP may not significantly reduce crop yield. The crop yield is taken into consideration and weed density or biomass of individual weeds (annual or perennial) is not so important while calculating the CPWC. Only weed density or biomass is considered for calculating weed control efficiency of a particular management practice for which the weed seed bank is also a criterion. However, weed biomass is the outcome after competition experienced by each weed species with the fellow crop and the weeds. Consequently, the weed pressure in the subsequent season will be the cumulative effect of the preceding season too, which is unaccounted for in CPWC. It is argued that in organic farming or low-input farming systems, where herbicides are not used, the concept of CPWC can be misleading and should be avoided. It is concluded that CTWR is more meaningful than the CPWC.
The nonconventional technique known as citrate precursor method has been successfully used to modify the magnetic properties of substituted Mg–Mn ferrites. We have found that the magnetic properties ...of these mixed ferrites change considerably by this method. It is observed that citrate precursor method could be used to obtain close composition control, better homogeneity, lower processing temperature, higher purity, lower porosity and more uniform grain growth. This results in favorable magnetic properties. In the present study, we have investigated various magnetic properties like saturation magnetization, magneton number, thermal variation of AC susceptibility, Neel temperature and initial permeability. In all the three series, the saturation magnetization and initial permeability improved significantly with indium and cobalt substitution. Neel temperature of each sample was calculated from AC susceptibility data. Higher values of Neel temperature were obtained for samples with increased content of cobalt. Magnetic losses obtained are from 1–2 orders lower as compared to those for Mg–Mn ferrites prepared by conventional ceramic method, which suits high-frequency applications. The possible mechanisms contributing to these properties are discussed in this paper.
Listeria
contamination in foods of animal origin is one of the most concerning food safety issues. A duplex, SYBR green-based, real-time PCR assay was developed with high-resolution melting ...analysis-based differentiation of the genus
Listeria
and
Listeria monocytogenes
. The primers were designed and tested against other related foodborne pathogens. The assay was optimized for standard parameters in a non-orthogonal fashion and validated following international standards. The LOD
abs
and LOQ of the assay were calculated to be 0.78 and 1.56 ng of the target DNA. The LOD
rel
of the assay was found to be 1%
Listeria
DNA in background DNA. The assay was evaluated for applicability in artificially spiked samples, providing a 120 CFU/ml detection. The assay was validated with proficiency test samples and also with samples collected for surveillance analysis. This well-established and validated assay can be utilized as a qualitative and quantitative tool for addressing the
Listeria
contamination in the food safety contexts.
Background and Aim
While European Society of Pediatric Gastroenterology Hepatology and Nutrition advocates a no‐biopsy pathway for the diagnosis of celiac disease (CeD) in children if IgA anti‐tissue ...transglutaminase antibody (anti‐tTG ab) titer is ≥10‐fold upper limit of normal (ULN) and have a positive IgA anti‐endomysial antibody (EMA); the data for anti‐tTG Ab titer‐based diagnosis of CeD in adults is still emerging. We planned to validate if IgA anti‐tTG Ab titer ≥10‐fold predicts villous abnormalities of modified Marsh grade ≥2 in Asian adult patients with CeD.
Methods
We recruited 937 adult patients with positive anti‐tTG Ab from two databases, including AIIMS Celiac Clinic and Indian National Biorepository. The diagnosis of definite CeD was made on the basis of a positive anti‐tTG Ab and the presence of villous abnormalities of modified Marsh grade ≥2.
Results
Of 937 adult patients with positive anti‐tTG Ab, 889 (91.2%) showed villous abnormalities of modified Marsh grade ≥2. Only 47.6% of 889 adults with CeD had anti‐ tTG Ab titers of ≥10‐fold. The positive predictive value (PPV) and specificity of anti tTG Ab titer ≥10‐fold for predicting modified Marsh grade ≥2 were 99.8% and 98%, respectively. At anti‐tTG Ab titer ≥11‐fold, specificity and PPV were 100% for predicting villous abnormalities of modified Marsh grade ≥2.
Conclusions
Approximately 50% of adults with CeD may benefit from the no biopsy pathway, reducing the health burden and risks of gastroscopy/anesthesia.
Chauhan BS, Migo T, Westerman PR & Johnson DE (2010). Post‐dispersal predation of weed seeds in rice fields. Weed Research 50, 553–560.
Summary
Post‐dispersal weed seed predation can cause a ...substantial reduction in the number of weed seeds entering the seed bank and, as a consequence, reduce the number of weeds growing in subsequent seasons. Investigations on seed predation on four tropical rice fields in the Philippines were conducted to determine (i) the magnitude of post‐dispersal seed predation after rice harvest, (ii) whether vertebrates or invertebrates are the main seed predators, (iii) whether seed predation is affected by crop residue, (iv) whether seed predation is affected by proximity to the field edge, and (v) whether predation differs among seeds of the grasses Digitaria ciliaris, Echinochloa colona and Eleusine indica. Seed removal rate over a 14‐day period ranged from 78% to 91% among fields, was slightly higher in the interior of the fields (89%) than in the field margins (85%) and slightly higher without residue cover (89%) than with (86%). Selective exclosures indicated that invertebrates, presumed to be mainly fire ants (Solenopsis geminata), were the main seed predators (96%) and vertebrates, presumed to be mainly rodents, secondary predators (38%). Seed removal of D. ciliaris was higher (93%) than of E. indica (88%) and E. colona (75%). Results suggest substantial seed predation could contribute to ecologically‐based weed management in rice. Further studies are required to determine season‐long seed predation rates and to confirm the identity of the predators involved. Ways to integrate these seed predators into prevailing cropping practices need to be developed.
Environmental pollution is one of the major concerns as it affects public health and is responsible for various neurological disorders too. Neurological disorders are governed by many different ...factors - they can be genetic, based on lifestyle, or environmental. In many recent studies, it has been observed that exposure to many environmental pollutants increases the risk of Alzheimer’s disease (AD). Pollutants like PM 10, PM2.5, and some other ultrafine nanoparticles, lipophilic vaporized toxicant (acrolein) can easily reach the brain by crossing the blood-brain barrier after it they can activate the innate immune responses inside the target site like neurons, astrocytes, and microglia by this way they can be neurotoxic. Human epidemiological evidence proves that there is a correlation between environmental pollutants and neurological disorders like dysfunction of mitochondrial, oxidative stress, disruption in the myelin sheath, the blood-brain barrier anatomy alterations, and endoplasmic reticulum stress which direct towards cognitive impairment with lower quality of lifestyle. The review article aims to culminate the correlation between the environmental factors and Alzheimer’s disease, The different sources of pollution and their effect on various stages of human life, developmental neurotoxicity, and neurological disorders also have been discussed.
Recrystallization of CL-20 to ε-polymorphic form Chauhan, B S; Thakur, A; Soni, P K ...
IOP conference series. Materials Science and Engineering,
01/2021, Letnik:
1033, Številka:
1
Journal Article
Recenzirano
Odprti dostop
High explosive CL-20 (2,4,6,8,10,12 - Hexanitro - 2,4,6,8,10,12 - hexaazaisowurtzitane) exists in four polymorphic forms i.e. α, β, γ and ε polymorphs at ambient conditions and polymorph ζ exists ...only at high pressure (1.44 GPa). CL-20 is the only single compound having highest energy among all the organic substances. But polymorphic form α- of CL-20 is generally obtained during most of the synthetic processes which has low density and high sensitivity. Thus, there is requirement of further recrystallization to obtain most stable ε-polymorphic form. Owing to the highest density, superior thermal stability and better insensitivity of ε- polymorph over other three polymorphs (α-, β- and γ- form) which are highly sensitive towards impact, friction and shock, ε- CL-20 is most desirable for use in defence applications. The present work studies the effect of various variables which influence the crystallisation process like effect of moisture, nature of solvent/anti-solvent and time on the preparation of ε- form of CL-20. Ethyl acetate and n-butyl acetate as solvents and toluene as anti-solvent resulted in the formation of desired ε- polymorphic form successfully. Polymorphic form was confirmed by FTIR and XRD analysis. SEM analysis was carried out for the morphological analysis of prepared samples.
Portulaca oleracea, a C₄ species, is reported to be a serious weed in 45 crops in 81 countries. Experiments were conducted in the laboratory, the screenhouse and the field to determine the influence ...of environmental factors on seed germination and seedling emergence of P. oleracea. In the laboratory, germination in the dark was low and was not influenced by the tested temperatures (35/25°C, 30/20°C and 25/15°C alternating day/night temperatures). In the light/dark regime, however, germination was lower at 25/15°C and 35/25°C than at 30/20°C (70%, 75% and 81% germination, respectively). In conditions of 106 mM sodium chloride or -0.34 MPa osmotic potential, seeds germinated to only 50% of maximum germination of the control. Germination was not influenced by buffered pH solutions ranging from 5 to 9. In the screenhouse, germination was greatest for seeds placed on the soil surface, but emergence declined with increasing seed burial depth in soil; no seedlings emerged from the depth of 2 cm. Seedling emergence and seedling dry matter were markedly reduced by the addition of rice residue to the soil surface at rates equivalent to 4 to 6 t ha⁻¹. In the field, seedling emergence of P. oleracea was greater under zero till (ZT) (17-20%) than under minimum tillage (6-10%), a likely reflection of low seed burial and exposure of seeds to light with a ZT system. This study identifies some of the factors enabling P. oleracea to be a widespread weed in the humid tropics, and the information could contribute to improved control strategies.
The study focusses on two major aspects: measurement methodology and uncertainty in the realization and dissemination of unit watt in airborne sound and consideration in legal sound regulations for ...various noise sources. Although sound power level is the fundamental unit invariant of distance from the source, yet there is no direct method for its measurement. An National Metrology Institute (NMI) perspective for the realization, dissemination and application of acoustical quantities: sound pressure and sound power level for strengthening the measurement traceability chain in India and formulation of legal noise limits and regulations of various noise sources is described. The low frequency limitations may yield different results using different methods, which thus necessitates the use of a harmonized approach in realizing the sound power parameter for improving the traceability for the unit watt in airborne sound. The use of sound power level and sound pressure level for noise labeling of appliances and other noise sources in India is recommended.
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