Direct observation and assessment of phase states of ambient and lab-generated sub-micron particles upon humidification.

We present a new analytical platform that uses a tilted stage (60°) integrated to the Peltier cooling stage interfaced with an Environmental Scanning Electron Microscope (ESEM) to directly observe and assess the phase state of particles as a function of RH at a controlled temperature. Three types of organic particles have been studied: (a) Suwannee River Fulvic Acid (SRFA) particles, (b) lab generated soil organic particles, and (c) field-collected ambient particles. The chemical composition, morphology, and functional groups of individual particles were probed using computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy (CCSEM/EDX) and scanning transmission X-ray microscopy with near-edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). Results show that all three types of particles are organic-rich, but soil organic particles and ambient particles contain a considerable amount of inorganic species. The phase state can be determined based on the particle's aspect ratio (particle width/height), which we proposed for solid, semisolid, and liquid particles are 1.00-1.30, 1.30-1.85, and >1.85, respectively. We found that solid SRFA particles transition to a semisolid state at ∼90% RH and to the liquid state at ∼97% RH, in agreement with the literature. The solid soil organic particles transition to a semisolid state at ∼85% RH and to the liquid state at ∼97% RH. The solid ambient organic particles transition to a semisolid state at ∼65% RH and the liquid state at ∼97% RH. Our results indicate that this new platform can directly observe and quantitatively indicate the phase transition of field-collected particles under different ambient conditions.

Sociodemographic Pattern of Postmenopausal Women and Health Issues: A Study in Rural Bathinda, Punjab.

BACKGROUND: The diminishing hormonal concentrations in women after menopause may trap them into a number of reproductive health deficits. Their lifestyle, occupation, dietary constituents, etc., affect the overall health. Unfortunately, women belonging to rural areas lack basic amenities and cultural aspects give them a backseat to pay heed to personal health. Therefore, it is important to take into consideration the demographic profile of rural women. OBJECTIVE: The objective of the study is to evaluate postmenopausal women of rural Punjab for sociodemographic, reproductive parameters and health issues. RESULTS: This study analyzed 425 women showing a high rate of illiteracy (74.6%), agricultural occupancy (85.2%), and consumption of vegetarian food (94.4%). The mean age at menarche and menopause was observed as 14.04 ± 1.12 and 47.97 ± 3.4 years, respectively. The most frequent complaints were fatigue (70.4%), backache (69.4), breathing problems (52.2%), and abdominal discomfort (43.1%). CONCLUSION: Later age at menopause in women was found concurrent with involvement in agriculture and exposure to pesticides. Delayed menopause may indicate a risk of reproductive cancers while protection in cardiovascular diseases. Therefore, age at menopause and dependent sociodemographic parameters should be considered important tools in determining the reproductive health of aging women. Large-scale studies dealing with this health aspect are warranted at village level.

Extensive Soot Compaction by Cloud Processing from Laboratory and Field Observations.

Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models.

Level of endosulfan among women in Talwandi Sabo Block of Southern Punjab, India.

Endosulfan is one of the most prevalent organochlorine pesticides used in the agricultural sector in the developing countries including India. It affects the physiological functioning of different organ systems including nervous, immune, hepatic, and reproductive system. Realizing the safety and health concern, restrictions have been imposed at various levels, but the usage has still continued in the plantation crops. Owing to pesticide beneficiary of north India, the cotton belt commonly called the Malwa region of Punjab was evaluated for identifying the levels of Endosulfan in the blood samples of women working in agricultural fields. Gas chromatograph with electron capture detector was used for detecting the levels of endosulfan metabolites among twenty active female workers. The mean level of endosulfan recorded in the tested population was observed to be 2.22 ppb. It is difficult to draw a certain conclusion based on these findings because the subjects were less in number. However, detection of even very low concentrations of endosulfan residues signifies its continued accessibility to the women population. Encouragement of more such population-based research needs to be adopted to determine the body burden of such pesticides in humans. The effective implementation of the ban on Endosulfan could be checked by a combined retrospective and prospective study to infer a justifiable impact.

Protein structural biology using cell-free platform from wheat germ.

One of the biggest bottlenecks for structural analysis of proteins remains the creation of high-yield and high-purity samples of the target protein. Cell-free protein synthesis technologies are powerful and customizable platforms for obtaining functional proteins of interest in short timeframes, while avoiding potential toxicity issues and permitting high-throughput screening. These methods have benefited many areas of genomic and proteomics research, therapeutics, vaccine development and protein chip constructions. In this work, we demonstrate a versatile and multiscale eukaryotic wheat germ cell-free protein expression pipeline to generate functional proteins of different sizes from multiple host organism and DNA source origins. We also report on a robust purification procedure, which can produce highly pure (> 98%) proteins with no specialized equipment required and minimal time invested. This pipeline successfully produced and analyzed proteins in all three major geometry formats used for structural biology including single particle analysis with electron microscopy, and both two-dimensional and three-dimensional protein crystallography. The flexibility of the wheat germ system in combination with the multiscale pipeline described here provides a new workflow for rapid production and purification of samples that may not be amenable to other recombinant approaches for structural characterization.

Folic acid, dietary habits, and homocysteine levels in relation to neural tube defects: A case-control study in North India.

PURPOSE: The present study attempts to understand the complex contribution of biochemical (plasma homocysteine) and nutritional parameters (dietary pattern and folate supplementation) to the neural tube defects (NTDs) affected pregnancies and controls in North Indian population. METHODS: Case-control study design was adopted to assess the role of folic acid, dietary habits, and homocysteine in relation to NTD births. The subjects comprised of 130 mothers of affected children (cases) and 233 mothers of healthy children (controls), who were either carrying NTD fetus or gave birth to NTD child. RESULTS: The mean homocysteine levels were elevated in cases (15.71 ± 8.35 µmol/L) as compared to controls (12.87 ± 5.95 µmol/L) but were lower among the non-vergetarians (13.55 ± 6.64 µmol/L) than the vegetarians (14.78 ± 7.93 µmol/L). Vegetarian dietary habit increased the NTD risk by 1.6 fold (95% CI = 1.0-2.7) while folic acid supplementation demonstrated a protective effect for conceptions (OR = 0.59; 95% CI = 0.3-0.9). Consumption of folic acid with non-vegetarian diet witnessed lowering of homocysteine in cases (12.88 ± 6.81 µmol/L) and in controls (11.85 ± 5.54 µmol/L), with an odds ratio depicting a 3.1 fold risk for consuming vegetarian diet without folic acid supplementation during the peri-conceptional period. CONCLUSION: It is suggested that plasma hyperhomocysteinemia bears negative impact on child-bearing women group, of north Indian ancestry, in modulating the risk of NTDs. Efforts should be made to enhance awareness regarding folic acid and vitamin B12 (non-vegetarian diet) supplementations alongwith proper nutritional intake among women, especially those consuming vegetarian diet to control homocysteine levels in order to reduce the risk of NTDs.

Effects of Endocrine-Disrupting Chemicals and Epigenetic Modifications in Ovarian Cancer: A Review.

Ovarian cancer (OC) is a relatively fatal female reproductive malignancy. Since the underlying causes are uncertain, it brings us to believe that both genetic and external factors contribute toward development of this lethal disorder. Exposure to endocrine-disrupting chemicals (EDCs) in the form of occupational usage of pesticides, fungicides, herbicides, plasticizers, cosmetics, and so on is potentially carcinogenic and their ability to cause epigenetic modifications has led us to hypothesize that they may play a catalytic role in OC progression. In response to synthetic chemicals, animal models have demonstrated disturbances in the development of ovaries and steroid hormonal levels but in humans, more research is required. The present review is an attempt to address the impact of EDCs on the hormonal system and gene methylation levels that may lead to malfunctioning of the ovaries which may consequently develop in the form of cancer. It can be concluded that endocrine disruptors do have a potential carcinogenicity and their high proportions in human body may cause epigenetic modifications, prompting ovarian surface epithelium to grow in an abnormal manner.

Toxicological profile of organochlorines aldrin and dieldrin: an Indian perspective.

Several epidemiological studies have suggested various environmental factors as a possible cause for increased incidence of various abnormalities. Of the various environmental contaminants, the most prevalent and the most discussed are the endocrine disrupting chemicals. Contact of such disruptors with humans has become inevitable today. They are cosmopolitan and present from agriculture to industrial sectors, even in day-to-day consumer products. Aldrin and dieldrin belong to one such class of substances which are known to have a toxic effect on various physiological systems of the human body. Despite an imposed ban on their manufacture and commercial use, these pesticides could still be detected in probable areas of consumption like agriculture. The present review discusses the known possible toxic effects of aldrin and dieldrin and their current existence in the ecosystem across India.

Enhanced light absorption by mixed source black and brown carbon particles in UK winter.

Black carbon (BC) and light-absorbing organic carbon (brown carbon, BrC) play key roles in warming the atmosphere, but the magnitude of their effects remains highly uncertain. Theoretical modelling and laboratory experiments demonstrate that coatings on BC can enhance BC's light absorption, therefore many climate models simply assume enhanced BC absorption by a factor of ∼1.5. However, recent field observations show negligible absorption enhancement, implying models may overestimate BC's warming. Here we report direct evidence of substantial field-measured BC absorption enhancement, with the magnitude strongly depending on BC coating amount. Increases in BC coating result from a combination of changing sources and photochemical aging processes. When the influence of BrC is accounted for, observationally constrained model calculations of the BC absorption enhancement can be reconciled with the observations. We conclude that the influence of coatings on BC absorption should be treated as a source and regionally specific parameter in climate models.

Beam characteristics of fiber-based supercontinuum light sources with mirror- and lens-based beam collimators.

Commercially available supercontinuum light sources that cover most of the solar spectrum are well suited for instrumentation, where a well-collimated beam with wide spectral coverage is needed. Typically, the optical power is emitted from a single-mode photonic-crystal fiber and the output can either be collimated using a proprietary, permanently integrated, lens-based collimator or with a customer-provided, off-axis parabolic mirror. Here, we evaluate both approaches and conclude that, superior beam quality and collimation over the whole spectral range can be obtained with an off-axis parabolic mirror, however at the price of a more complex and bulky system requiring additional user alignment.