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Pulp and paper industries emit various odorous gases during the pulp production and paper-making phase, which are unpleasant and have harmful effects on the human body. The working staffs are continuously exposed to these gases and develop various health issues. Hence, regular monitoring and analysis of such gases are necessary to avoid any sudden high concentration exposure and to prevent adverse health effects on the staff. An electronic nose (EN) has an array of gas sensors with an alert system for early detection of gases. Various ENs have been developed for varying applications till date. The detailed knowledge of the sensors used, their sensitivity and technology is helpful in development of any EN. The objective of this study is to comprehensively review various developed ENs with respect to their gas sensing and pattern recognition (PR) technologies. The information on gases released from pulp and paper industries is also compiled. The evolution of EN technology, its various applications, challenges in developing EN and its utility in safeguarding the industrial workers' life have been described. Further, gap analysis among previously developed EN, contemporary EN and wireless sensor network (WSN) is elaborated. It will facilitate future researchers for better selection of sensors and PR technologies while developing EN. The commonly used sensing technologies are described with their advantages, disadvantages and working principles. Metal oxide semiconductor (MOS) gas sensor and ANN algorithm show better result and hence recommended in the development of EN, whereas ZigBee protocol has been widely used for WSN.

Rural areas of developing countries have various indoor air pollution sources along with solid fuels used for cooking. This study aims to compare five indoor air pollution sources, viz., incense stick, dhoop, mosquito coil, cigarette, and cooking fuel charcoal, with respect to their pollution potential. The monitoring of PM, CO, CO2, NO2, and particulate bound heavy metals was carried out. Dhoop (DH1) was found to be emitting the highest concentration of metal Sb among all the analyzed metals. Dhoop, incense sticks, mosquito coil, and charcoal were found to be having high pollution potential. The first-order decay rate equation indicated that the highest decay rate constant per hour was observed with dhoop (DH1) for PM10 and PM2.5 and with mosquito coil (M1) for CO. The highest half-life of PM10 and PM2.5 was observed for cigarette (CG1) and charcoal (C1) respectively indicating their slow decay in air. The average daily dose values indicated that the age group 6 to < 11 years, 11 to < 16 years, and 31 to < 51 years will be more vulnerable to PM emissions from dhoop (DH1) and incense stick (IS1). The highest hazard index was estimated for incense stick (IS1) and charcoal. Significant carcinogenic risk was observed from cigarette and charcoal. The multiple-path particle dosimetry (MPPD) model was used to estimate the deposition of PM fractions in various regions of the human body.

This study aims to understand dust generation in classroom indoor for different chalk varieties and their potential doses to receptors in correlation with their physicochemical properties. Two representative chalks of extruded calcium carbonate and moulded gypsum type (total four) were used for writing on ceramic and wooden boards. Chalks were characterized using analytical techniques. Investigation of Particulate Matter (PM): PM2.5, PM10 and Total Suspended Particulate (TSP) concentrations in classroom air generated during the writing and wiping with chalk and board system was done. Dust collected beneath the board was analyzed for particle size distribution. Calcium carbonate made dustless chalks generate less PM during writing and wiping. They are quick settling and non-interacting with receptors, and deliver better utilization of material as compared to gypsum chalks. Physicochemical properties of the chalk constituents were invoked to explain the dust generation and its impact on the user. Surprisingly, dustless chalk made from Gypsum cannot be called really as dustless because of more PM emissions. The age-specific average potential dose for both PM10 and PM2.5 is higher for gypsum chalk as compared to the calcium carbonate chalks. The highest dose was estimated for the children in the age group of 6–11 years.

Enhanced transport of dust with the prevailing mid to upper tropospheric westerly winds from arid regions in South-west Asia and North-west India into the Indo-Gangetic Plain (IGP) and the influx of marine aerosol from the Arabian Sea (AS), Tropical Indian Ocean (TIO) and Southern Bay of Bengal (SBoB) into India along with the low level south-west wind flow during the onset of the South-west (SW) monsoon, 2014 was observed in campaign mode. Ambient airborne particulates (PM 2.5 and PM 10 ) were collected at 9 sites in and around IGP, India, viz. Patiala, Delhi, Lucknow, Varanasi, Giridih, Kolkata, Darjeeling, Bhubaneswar and Nagpur; over AS, TIO and SBoB providing a glimpse into the aerosol loading and its transport mechanisms. The highest average PM 2.5 (61.8 ± 18.6 μg m −3 ) and PM 10 (182.2 ± 58.0 μg m −3 ) mass concentrations were recorded at Delhi (upper IGP) and Lucknow (middle IGP) respectively. Average PM 2.5 (18.1 ± 10.1 μg m −3 ) and PM 10 (39.6 ± 15.8 μg m −3 ) levels recorded over the open oceanic regions in AS, TIO and SBoB were much lower than those observed over the land stations and the average PM 2.5 recorded over coastal AS and SBoB (49.1 ± 28.7 μg m −3 ). Cluster analysis, Potential Source Contribution Function (PSCF) and Concentration Weighted Trajectory (CWT) analysis portray that PM 2.5 and PM 10 levels at the land stations were influenced by weak to moderate contributions from AS, BoB, the arid South-west Asia and North-west India, peninsular India and from the polluted IGP region.

CSIR-CSMCRI's Chlorella variabilis (ATCC 12198) was evaluated through autotrophic, mixotrophic and heterotrophic growth for lipid production. Autotrophic growth was assessed by providing sodium bicarbonate/sodium carbonate/CO2 (air in a medium). Higher lipid productivity (115.94 mg L−1 d−1) with higher biomass productivity (724.98 mg L−1 d−1) of this strain was attained through bicarbonate and CO2 sequestration in a photobioreactor. Ability to regulate the pH in favorable bicarbonate/carbonate ratio showed its potential in alkaline effluent based carbon sequestration system for biofuel generation. The simultaneous study was also conducted to understand the effect of elevated CO2 (0.4, 1 and 1.2 g L−1) in air on the culture to assess adaptation, growth and lipid in the closed chamber conditions. It was observed that CO2 sequestration by the microalgae from the CO2 enriched environment was optimum at 1 g L−1 C. variabilis adapted to comparatively higher CO2 (1 g L−1) but grew better in low CO2 (0.4 g L−1). It was also observed that the growth, lipid content and fatty acid composition was significantly affected by CO2 supply strategies. The effect of intermittently added sodium bicarbonate at different pH on microalgal lipid content and composition of fatty acids was observed which could affect the quality of biodiesel. The effect on fatty acid composition was observed in response to carbon supply mode during the microalgal growth at different pH dictating the properties of biodiesel.

The objective of this study is to understand the fatty acid composition of a naturally floating microalgal mat with respect to seasonal variations in the water of a eutrophic lagoon on the west coast of India. The floating microalgal mat was explored for its bioaccumulation of metals and lipids for sustainable utilization in biofuel production. The effects of the nutrient profile and heavy metals in the water on the community composition of microalgal mat in different seasons were also studied and a principal component analysis was performed. It was observed that the unsaturated fatty acids such as C18:1 n 9c and C18:2 n 6c increased in low temperatures. The reverse effect was observed during the pre-monsoon season with augmented C16:0 fatty acid and an overall increment in saturated fatty acids. The Cyanophyceae and diatom community nurtured the growth during the pre-monsoon season by acquiring a higher bioaccumulation concentration factor (BCF) for Mn (3812.6 ± 680), As (90.47 ± 15.38), Ni (1620 ± 163.64), Cr (73.27 ± 21.23), and Cu (46.40 ± 11.44). The higher abundance of Cyanophyceae in the microalgal mat exhibited better metal endurance during the pre-monsoon season, which could be obviously tilized for the bioremediation of heavy metals. The biodiesel prepared from the microalgal mat met European biodiesel standards.

River Sabarmati is one of the biggest and major river of Gujarat that runs through two major cities of Gujarat, Gandhinagar and Ahmedabad and finally meets the Gulf of Khambhat (GoK) in the Arabian Sea. A study was conducted to evaluate the water quality of this river, as it could possibly be one of the major sources for filling up Kalpasar, the proposed man-made freshwater reservoir supposed to be the biggest one in the world. A total of nine sampling stations were established covering 163 km stretch of the river from upstream of Gandhinagar city to Vataman near Sabarmati estuary. Physicochemical (temprature, pH, salinity, chloride, total dissolved solids, turbidity, dissolved oxygen, biochemical oxygen demand, phenol, and petroleum hydrocarbons), biological (phytoplankton), and microbiological (total and selective bacterial count) analyses indicated that the river stretch from Ahmedabad-Vasana barriage to Vataman was highly polluted due to perennial waste discharges mainly from municipal drainage and industries. An implementation of sustainable management plan with proper treatment of both municipal and industrial effluents is essential to prevent further deterioration of the water quality of this river.

Isolated systolic hypertension is the most common hemodynamic form of hypertension in the elderly. With a rapidly aging population, the prevalence of hypertension, particularly isolated systolic hypertension, is expected to increase substantially. This phenomenon of increasing systolic pressure in the elderly is believed to be secondary to pathophysiological changes of aging as well as modifiable risk factors. Isolated systolic hypertension is associated with substantial mortality and morbidity, particularly of cerebrovascular disease. It is a rapidly growing public health concern and its management continues to remain a challenge to practicing physicians. Recent studies like the Systolic Blood Pressure Intervention Trial (SPRINT) and Heart Outcomes Prevention Evaluation (HOPE)-3 have implications for antihypertensive therapy in general and for the management of isolated systolic hypertension in particular. In this article we will review: 1) epidemiology and pathophysiologic mechanisms, 2) impact of isolated systolic hypertension on cardiovascular outcomes, 3) optimal management strategies, and 4) systolic blood pressure goals in the light of SPRINT and HOPE 3 trials.

Heavy metal concentrations in suspended particulate matter (SPM) were investigated for their distribution and source in the atmosphere of coastal industrial town, Mithapur, Gujarat, India. SPM, at 10 locations covering three seasons, were trapped on glass fibre filters using high volume samplers and quantification of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) was done using Atomic Absorption Spectrometry employing HNO3 based wet digestion. Results show relatively low concentrations of SPM (211.3 to 375.2 μg/m3) compared to National Ambient Air Quality Standard (NAAQS), specified By Central Pollution Control Board (CPCB, India), however, they were 2–3 times higher as compared to reference site. Among the heavy metals Cr, Mn and Pb levels were low, while Ni and Cd found to be exceeding the USEPA standards. The metal levels were also compared with those reported for other rural, coastal, industrial and urban parts around the world. Enrichment Factor analysis indicated that Cd, Zn, Cu, Pb and Ni were highly enriched relative to their crustal ratios (to Fe) and correspond to substantial contribution of anthropogenic source of these metals. The source identification was carried out by principal component analysis by applying a Varimax Rotated Component Matrix.

The concentration of selected heavy metals, like As, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn as well as B, was measured by inductively coupled plasma-optical emission spectrometry (ICP-OES) in groundwater samples from various locations in the Gulf of Khambhat (GoK), an inlet of the Arabian Sea in the state of Gujarat, India, during post-monsoon, winter, and pre-monsoon seasons in a year. Most heavy elements are characterized by low mobility under slightly alkaline and reducing conditions; concentrations in confined aquifers are smaller than the maximum permissible values for drinking water. The temporal changes indicate that a majority of metals is entering the aquifer during monsoon. Principle component analysis of the heavy metal data suggests that Co, Cu, Cd, and Zn are interrelated with each other and derived significantly from anthropogenic route, while input of Pb and Cr may be due to atmospheric deposition in the study area. Both weathering of rocks and anthropogenic input were found to be main sources of elements in the groundwater. The heavy metal levels in groundwaters of the GoK region in comparison with some of the European and Asian sites were higher; however, these metal levels were found to be comparable with few urban sites in the world.

In the present study, the impact of the flyover construction to curb traffic congestion problem has been assessed in terms of traffic decongestion, time saving, fuel saving and emission reduction. A flyover has also been constructed over four signalized junctions in the main commercial area in Nagpur city, India. It was found that about 35% of the total traffic is diverted to the flyover, which results in a reduction of about 32% in the total emission generation. Travel on the flyover resulted in as much as 60-70% saving in time, compared to the travel on the main road, particularly when all the four signals are found to be in the red phase. The loss of fuel for combustion and the associated cost resulting from waiting for the signal to change are also estimated, and these are found to be significant.