Atmospheric chemistry and cancer risk assessment of Polycyclic Aromatic Hydrocarbons (PAHs) and Nitro-PAHs over a semi-arid site in the Indo-Gangetic plain.

Polycyclic Aromatic Hydrocarbons (PAHs) and Nitro-PAHs were collected over a year at a traffic dominated site in Agra, to determine the dominant partitioning mechanism. During the entire sampling period, total PAHs and Nitro-PAHs were 3465 ± 3802 and 26.1 ± 25.9 ng m-3 respectively. The gas-particle partitioning behavior of PAHs was studied by applying the Pankow model, Absorption model, and Dual model. Amongst all the partitioning models, the Dual model fits well and indicates that the partitioning of PAHs at the traffic site in Agra depends on both the physical adsorption of PAHs on the Total Suspended Particulate (TSP) surface and absorption of PAHs into the organic layer present on the TSP surface. Pankow model indicates that PAHs are emitted from the source close to the sampling point and due to this PAHs do not get enough time to get partitioned in between both the phases. Incremental lifetime Cancer Risk (ILCR) shows that adults and children are more prone to cancer risk in comparison to infants for both PAHs and Nitro-PAHs. Cancer risk by inhalation was minimum in comparison to both ingestion and dermal exposure. Nitro-PAHs in the particulate phase were high enough to exceed the minimum permissible limit (10-6) of causing cancer by ingestion and dermal exposure.

Mutagenic and Cancer Risk Estimation of Particulate Bound Polycyclic Aromatic Hydrocarbons from the Emission of Different Biomass Fuels.

Smoke samples from combustion of different biomass fuels were analyzed for the particulate bound Polycyclic Aromatic Hydrocarbons (PAHs) due to their carcinogenic and mutagenic nature. Out of 16 priority PAHs, 11 PAHs were detected in the emission of fuels, while the remaining 5 PAHs (chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[g,h,i]perylene) were below the detection limit. The highest emission factor for the sum of all the PAHs was found for coal (353.08 mg kg-1), charcoal (27.28 mg kg-1), and the various wood types. Emission rates of total PAHs ranged from 0.37 to 5.15 mg h-1 with the highest value for bituminous coal (5.15 mg h-1) and lowest for Polyalthia longifolia (0.37 mg h-1). A cancer risk assessment was done for infants, children, and adults using the incremental lifetime cancer risk (ILCR) model via ingestion, inhalation, and dermal contact pathway. The ILCR values ranged from 10-11 to 10-6, and a higher cancer risk was observed for children and adults in comparison to infants. PAH concentrations emitted from biomass emissions shows a direct correlation with mutagenesis to humans, indicating a higher potential for the frameshift mutation as compared to base-pair mutation for dung, bituminous coal, charcoal, Dalbergia sissoo, Psidium guajava, Ziziphus mauritana, Polyalthia longifolia, and Ailanthus trithesa.

Chemical fractionation of heavy metals in fine particulate matter and their health risk assessment through inhalation exposure pathway.

Samples of PM2.5 were collected from an urban area close to a national highway in Agra, India and sequentially extracted into four different fractions: water soluble (F1), reducible (F2), oxidizable (F3) and residual fraction (F4) for chemical fractionation of arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), nickel (Ni) and lead (Pb). The metals were analyzed by inductively coupled plasma optical emission spectroscopy in each fraction. The average mass concentration of PM2.5 was 93 ± 24 µg m-3.The total concentrations of Cr, Pb, Ni, Co, As and Cd in fine particle were 192 ± 54, 128 ± 25, 108 ± 34, 36 ± 6, 35 ± 5 and 8 ± 2 ng m-3, respectively. Results indicated that Cd and Co had the most bioavailability indexes. Risk Assessment Code and contamination factors were calculated to assess the environmental risk. The present study evaluated the potential Pb hazard to young children using the Integrated Exposure Uptake Biokinetic Model. From the model, the probability density of PbB (blood lead level) revealed that at the prevailing atmospheric concentration, 0.302 children are expected to have PbB concentrations exceeding 10 µg dL-1 and an estimated IQ (intelligence quotient) loss of 1.8 points. The predicted blood Pb levels belong to Group 3 (PbB < 5 µg dL-1). Based on the bioavailable fractions, carcinogenic and non-carcinogenic risks via inhalation exposure were assessed for infants, toddlers, children, males and females. The hazard index for potential toxic metals was 2.50, which was higher than the safe limit (1). However, the combined carcinogenic risk for infants, toddlers, children, males and females was marginally higher than the precautionary criterion (10-6).

Chemical partitioning of fine particle-bound As, Cd, Cr, Ni, Co, Pb and assessment of associated cancer risk due to inhalation, ingestion and dermal exposure.

The bioavailability and human health risks of As, Pb, Ni, Co, Cr and Cd in fine particulate matter (PM2.5) at an urban site on a National highway in Agra, India were investigated. Inductively coupled plasma-optical emission spectrometer was used for metal analysis in sequentially extracted samples to ascertain the highly mobile, reducible, bioavailable and immobile fractions of the metals. Cancer risk resulting from inhalation, dermal and ingestion exposure to each metal in these fractions was calculated according to US EPA models. The average mass concentration of PM2.5 was 87.16 ± 62.51 µg/m3. Cr, Ni and Pb were the most abundant metals. The results showed that Pb and Cr were higher in the mobile fraction. Cd and Co had high bioavailability. Ingestion is the major exposure pathway for all heavy metals except Cr to infants, children and adults followed by inhalation and dermal contact. The cumulative risk for Cr(VI) due to dermal and inhalation routes exceed the maximum acceptable limit for children of age 1-7 years, 8-15 years and adults when total concentration is considered, but the estimated risks are within the acceptable limit when the bioavailable, water soluble and mobile fraction are taken into account. Hence the study shows that children and adults living in the vicinity of this site are more susceptible, hence more attention should be paid to protect them from pollution hazards. The study indicates the importance of metal speciation in assessing associated human health risks.

Takotsubo Cardiomyopathy in a Post-COVID Case.

Takotsubo cardiomyopathy (TTC) is a unique heart disease that mimics the clinical presentation of acute coronary syndrome and is seen more commonly in post-menopausal females. Here, we report a case that presents an ideal documentation of TTC depicting its characteristic clinical features and possible outcomes. TTC usually culminates in a complete reversal of both systolic and diastolic dysfunctions, however in our case of a post-COVID scenario, the persisting, rather worsening diastolic dysfunction might be a residual manifestation of COVID-19 myocarditis. Recent reports have found an increasing prevalence of TTC amidst the COVID-19 pandemic possibly as a result of the emotional and physical stress, and subsequent catecholamine surge caused by the virus in such patients. There might exist an independent association between TTC and the COVID-19 virus. Increased clinical evidence is required to establish the strength of this relationship, if any.

Hazardous particles during diesel engine cold-start and warm-up: Characterisation of particulate mass and number under the impact of biofuel and lubricating oil.

The increasing share of using biofuels in vehicles (mandated by current regulations) leads to a reduction in particle size, resulting in increased particle toxicity. However, existing regulations disregarded small particles (sub-23 nm) that are more toxic. This impact is more significant during vehicle cold-start operation, which is an inevitable frequent daily driving norm where after-treatment systems prove ineffective. This study investigates the impact of biofuel and lubricating oil (as a source of nanoparticles) on the concentration, size distribution, median diameter of PN and PM, and their proportion at size ranges within accumulation and nucleation modes during four phases of cold-start and warm-up engine operation (diesel-trucks/busses application). The fuels used were 10% and 15% biofuel and with the addition of 5% lubricating oil to the fuel. Results show that as the engine warms up, PN for all the fuels increases and the size of particles decreases. PN concentration with a fully warmed-up engine was up to 132% higher than the cold-start. Sub-23 nm particles accounted for a significant proportion of PN (9%) but a smaller proportion of PM (0.1%). The fuel blend with 5% lubricating oil showed a significant increase in PN concentration and a decrease in particle size during cold-start.

Soot particle morphology and nanostructure with oxygenated fuels: A comparative study into cold-start and hot-start operation.

This study investigates the morphology and nanostructure of soot particles during cold-start and hot-start engine operation of a diesel engine using oxygenated fuels. The soot samples were analysed using transmission electron microscopy. The oxygen content in the fuel was varied between 0 and 12%. The results showed that the primary particles during cold-start have significantly smaller size when compared to hot-start engine operation. The addition of oxygenated fuels also resulted in smaller sized primary particles. Smaller radius of gyration and higher fractal dimension of soot aggregates during cold-start would mean smaller aggregate size with a more compact structure. Shorter fringes with a higher inter-fringe spacing for cold-start would mean lower graphitisation of soot particles that could be related to higher oxidation reactivity of soot particles.

Analysis of cold-start NO2 and NOx emissions, and the NO2/NOx ratio in a diesel engine powered with different diesel-biodiesel blends.

In the transportation sector, the share of biofuels such as biodiesel is increasing and it is known that such fuels significantly affect NOx emissions. In addition to NOx emission from diesel engines, which is a significant challenge to vehicle manufacturers in the most recent emissions regulation (Euro 6.2), this study investigates NO2 which is a toxic emission that is currently unregulated but is a focus to be regulated in the next regulation (Euro 7). This manuscript studies how the increasing share of biofuels affects the NO2, NOx, and NO2/NOx ratio during cold-start (in which the after-treatment systems are not well-effective and mostly happens in urban areas). Using a turbocharged cummins diesel engine (with common-rail system) fueled with diesel and biofuel derived from coconut (10 and 20% blending ratio), this study divides the engine warm-up period into 7 stages and investigates official cold- and hot-operation periods in addition to some intermediate stages that are not defined as cold in the regulation and also cannot be considered as hot-operation. Engine coolant, lubricating oil and exhaust temperatures, injection timing, cylinder pressure, and rate of heat release data were used to explain the observed trends. Results showed that cold-operation NOx, NO2, and NO2/NOx ratio were 31-60%, 1.14-2.42 times, and 3-8% higher than the hot-operation, respectively. In most stages, NO2 and the NO2/NOx ratio with diesel had the lowest value and they increased with an increase of biofuel in the blend. An injection strategy change significantly shifted the in-cylinder pressure and heat release diagrams, aligned with the sudden NOx drop during the engine warm-up. The adverse effect of cold-operation on NOx emissions increased with increasing biofuel share.

Choosing Optimal Seed Nodes in Competitive Contagion.

In recent years there has been a growing interest in simulating competitive markets to find out the efficient ways to advertise a product or spread an ideology. Along this line, we consider a binary competitive contagion process where two infections, A and B, interact with each other and diffuse simultaneously in a network. We investigate which is the best centrality measure to find out the seed nodes a company should adopt in the presence of rivals so that it can maximize its influence. These nodes can be used as the initial spreaders or advertisers by firms when two firms compete with each other. Each node is assigned a price tag to become an initial advertiser which varies according to their importance in the network. Considering their fixed budgets, they initially determine the payoff of their products and the number of their initial seeds in the network. Under this setting, we study the question of whether to choose a small number of influential nodes or a larger number of less influential nodes.

Chemical fractionation, bioavailability, and health risks of heavy metals in fine particulate matter at a site in the Indo-Gangetic Plain, India.

In the present study, the distribution and chemical fractionation of heavy metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in PM2.5 collected at Sikandarpur in Agra from September 2015 to February 2016 were carried out to evaluate their mobility potential, environmental, and human health risk through inhalation. Sequential extraction procedure was applied to partition the heavy metals into four fractions (soluble and exchangeable fraction (F1); carbonates, oxides, and reducible fraction (F2); bound to organic matter, oxidizable, and sulphidic fraction (F3); and residual fraction (F4)) in PM2.5 samples. The metals in each fraction were analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Daily PM2.5 concentration ranged between 13 and 238 µg m-3 during the study period. For more than 92% of the days, the mass concentrations were greater than the National Ambient Air Quality Standard (NAAQS) set at 60 µg m-3. The total mass concentration of the eight metals was 3.3 µg m-3 that accounted for 2.5% of the PM2.5 mass concentration and followed the order Fe > Zn > Cu > Mn > Pb > Ni > Cd > Cr in dominance. The carcinogenic metals (Cd, Cr, Ni, and Pb) comprised 10% of the total metal determined. Almost all the metals had the highest proportion in the residual fraction (F4) except Ni, which had the highest proportion in the reducible fraction (F2). Chemical fractionation and contamination factor (CF) showed that Pb and Ni are readily mobilized and more bioavailable. Risk assessment code (RAC) showed that Cd, Cu, Mn, Ni, Pb, and Zn had medium environmental risk, while Cr and Fe had low risk. When the bioavailable (F1 + F2) concentrations were applied to calculate non-carcinogenic and carcinogenic risk, the results showed that the value of hazard index (HI) for toxic metals was 1.7 for both children and adults through inhalation. The integrated carcinogenic risk was 1.8 × 10-6 for children and 7.3 × 10-6 for adults, with both values being higher than the precautionary criterion (1 × 10-6). Enrichment factor (EF) calculations showed that Cd, Pb, Zn, and Ni were enriched being contributed by anthropogenic activities carried out in the industrial sectors of the city.

Effect of cold start on engine performance and emissions from diesel engines using IMO-Compliant distillate fuels.

Emissions from ships at berth are small compared to the total ship emissions; however, they are one of the main contributors to pollutants in the air of densely-populated areas, consequently heavily affecting public health. This is due to auxiliary marine engines being used to generate electric power and steam for heating and providing services. The present study has been conducted on an engine representative of a marine auxiliary, which was a heavy duty, six-cylinder, turbocharged and after-cooled engine with a high pressure common rail injection system. Engine performance and emission characterisations during cold start are the focus of this paper, since cold start is significantly influential. Three tested fuels were used, including the reference diesel and two IMO (International Maritime Organization) compliant spiked fuels. The research engine was operated at a constant speed and 25% load condition after 12 h cooled soak. Results show that during cold start, significant heat generated from combustion is used to heat the engine block, coolant and lubricant. During the first minute, compared to the second minute, emissions of particle number (PN), carbon monoxide (CO), particulate matter (PM), and nitrogen oxides (NOx) were approximately 10, 4, 2 and 1.5 times higher, respectively. The engine control unit (ECU) plays a vital role in reducing engine emissions by changing the engine injection strategy based on the engine coolant temperature. IMO-compliant fuels, which were higher viscosity fuels associated with high sulphur content, resulted in an engine emission increase during cold start. It should be taken into account that auxiliary marine diesel engines, working at partial load conditions during cold start, contribute considerably to emissions in coastal areas. It demonstrates a need to implement practical measures, such as engine pre-heating, to obtain both environmental and public health advantages in coastal areas.

Native aortic valve endocarditis caused by Candida sake.

The case is presented of a native valve endocarditis caused by Candida sake in a 34-year-old farmer with no history of intravenous drug abuse or pre-existing valvular abnormality. The patient presented with septicemia and multiorgan dysfunction syndrome (MODS). Clinical and diagnostic work-up revealed findings of severe aortic regurgitation and large vegetations on the aortic valve. Preoperatively, the patient was treated for three weeks with amphotericin B; when the MODS had improved, open-heart surgery with valve replacement was performed. Intravenous amphotericin B was continued postoperatively for three more weeks; a subsequent decision was taken to administer lifelong suppressive antifungal therapy.

Diesel engine performance and emissions with fuels derived from waste tyres.

The disposal of waste rubber and scrap tyres is a significant issue globally; disposal into stockpiles and landfill poses a serious threat to the environment, in addition to creating ecological problems. Fuel production from tyre waste could form part of the solution to this global issue. Therefore, this paper studies the potential of fuels derived from waste tyres as alternatives to diesel. Production methods and the influence of reactor operating parameters (such as reactor temperature and catalyst type) on oil yield are outlined. These have a major effect on the performance and emission characteristics of diesel engines when using tyre derived fuels. In general, tyre derived fuels increase the brake specific fuel consumption and decrease the brake thermal efficiency. The majority of studies indicate that NOx emissions increase with waste tyre derived fuels; however, a few studies have reported the opposite trend. A similar increasing trend has been observed for CO and CO2 emissions. Although most studies reported an increase in HC emission owing to lower cetane number and higher density, some studies have reported reduced HC emissions. It has been found that the higher aromatic content in such fuels can lead to increased particulate matter emissions.

Atmospheric concentrations and gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs at Indo-Gangetic sites.

Aerosol samples in the dual-phase (gaseous and particulate) were collected simultaneously for the first time in Agra at a rural and a traffic dominated site during post-monsoon and winter seasons to investigate the gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs). The samples were collected using a high volume sampler on quartz micro-fiber filter papers and polyurethane foam plugs for particulate and gas phases respectively. The samples were extracted in a mixture of DCM and n-hexane. 16 priority PAHs and two nitro-PAHs were analyzed using gas chromatograph-mass spectrometry. The total concentration of PAHs (gas + particulate) was 4015 and 624 ng m-3 at the traffic and rural sites respectively. Two and three ring PAHs were dominant in the gas phase while four, five and six ring PAHs were abundant in the particle phase. A statistically significant correlation (r2 = 0.69-0.98, p < 0.001) for log Kpvs. was obtained for individual PAHs at both sites where slopes varied between -2.83 and -0.04 at the traffic site and from -3.15 to -0.06 at the rural site. Regression statistics of Clausius-Clapeyron plots suggest that the concentration of highly volatile PAHs in the atmosphere is influenced by temperature. The gas-particle partitioning coefficient Kp in its logarithmic form correlated with 1/T (r2 = 0.5-0.95, p < 0.001) and a positive slope for individual PAHs was found. In health risk assessment DbA was found to be the most carcinogenic and mutagenic as compared to other PAHs followed by BaP. 1-NPyr had a larger contribution to BaP-TEQ than 3-NFla.

Comparison of Clinical Outcomes Following Single versus Multivessel Percutaneous Coronary Intervention Using Biodegradable Polymer Coated Sirolimus-Eluting Stent in an All-comers Patient Population.

BACKGROUND: Drug-eluting stents (DES) have been shown to reduce the rate of acute complications and the need for subsequent revascularization in cases where single-vessels are treated. The performance of DES in patients with multivessel disease and complex lesions, however, remains controversial. This study assessed and compared clinical outcomes following single vs. multivessel percutaneous coronary intervention (PCI), using the Supraflex sirolimus-eluting stent (SES), in an all-comers patient population. METHODS: We conducted retrospective, multicenter, all-comers, observational study of 995 patients, who underwent either single-vessel PCI (n=769 patients; group-I) or multivessel PCI (n=226 patients; group-II), treated with the biodegradable polymer coated Supraflex SES, between July-2013 and May-2014 at nine different centers in India. Pre-specified primary endpoint, rate of major adverse cardiac events (MACE) [defined as composite of cardiac death, myocardial infarction (MI), target lesion revascularization (TLR) and non-target lesion target vessel revascularization (non-TL TVR)], was analyzed during 12 months after the post-index procedure. We also analyzed the incidence of stent thrombosis (ST) as a safety endpoint during the follow-up period, as defined by the Academic Research Consortium (ARC). RESULTS: Of the whole study group, 1,242 lesions were treated in 995 patients (mean age 61.6±10.8 years; 80.0% male) with average stent length of 26.8±9.3 mm. Multivessel PCI patients were older, had a higher prevalence of arterial hypertension, were smoker, had a family history of coronary artery disease, previous stroke and previous PCI compared to single-vessel PCI patients. Follow-up was available in 99.0% (761/769) of patients with single-vessel intervention and 96.9% (219/226) of patients with multivessel intervention at the end of 12 months. In-hospital MACE was similar for both the groups [group-I, 3 (0.4%) vs. group-II, 1 (0.4%); p=1.000]. The observed MACE for group-I and group-II, at 30 days, 6 and 12 months follow-up were 9 (1.2%) vs. 2 (0.9%); p=1.000, 15 (2.0%) vs. 7 (3.2%); p=0.302 and 24 (3.2%) vs. 12 (5.5%); p=0.109, respectively. The cumulative incidence curves for MACE showed no significant differences between the two groups, at the end of 12 months (p=0.109). CONCLUSION: Our study shows that use of the Supraflex SES in single and multivessel coronary artery disease produces good clinical outcomes during 12 months of follow-up with a low rate of revascularization, despite complex lesion morphology.

Clinical outcomes in 995 unselected real-world patients treated with an ultrathin biodegradable polymer-coated sirolimus-eluting stent: 12-month results from the FLEX Registry.

OBJECTIVES: To evaluate, in the FLEX Registry, clinical outcomes of an ultrathin (60 µm) biodegradable polymer-coated Supraflex sirolimus-eluting stent (SES) for the treatment of coronary artery disease. Additionally, to determine the vascular response to the Supraflex SES through optical coherence tomography (OCT) analysis. SETTING: Multicentre, single-arm, all-comers, observational registry of patients who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India. PARTICIPANTS: 995 patients (1242 lesions) who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India. A total of 47 participants underwent OCT analysis at 6 months' follow-up. INTERVENTIONS: Percutaneous coronary intervention with Supraflex SES, PRIMARY AND SECONDARY OUTCOME MEASURES: The primary endpoint-the rate of major adverse cardiac events (defined as a composite of cardiac death, myocardial infarction (MI), target lesion revascularisation (TLR))-was analysed during 12 months. RESULTS: At 12 months, the primary endpoint occurred in 36 (3.7%) of 980 patients, consisting of 18 (1.8%) cardiac deaths, 16 (1.6%) MI, 7 (0.7%) TLR and 2 (0.2%) cases of non-target lesion target vessel revascularization. In a subset of 47 patients, 1227 cross-sections (9309 struts) were analysed at 6 months by OCT. Overall, a high percentage of struts was covered (98.1%), with a mean neointimal thickness of 0.13 ± 0.06 µm. CONCLUSIONS: The FLEX Registry evaluated clinical outcomes in real-world and more complex cohorts and thus provides evidence that the Supraflex SEX can be used safely and routinely in a broader percutaneous coronary intervention population. Also, the Supraflex SES showed high percentage of stent strut coverage and good stent apposition during OCT follow-up.

Warning leak of intracranial aneurysm masquerading as sinus node dysfunction: A case report.

We describe the successful endovascular repair of an intracranial aneurysm causing subarachnoid hemorrhage in a 62-year-old man, who was initially diagnosed and treated as a case of symptomatic sinus bradycardia. The aim of this report and following discussion is to discuss the subtle warning signs of intracranial aneurysm that may masquerade as sinus node dysfunction.

Delayed embolization of Amplatzer septal occluder device: an unknown entity--a case report.

A case of delayed embolization of Amplatzer septal occluder, occurring at 2 weeks postimplantation in a 10-year-old girl with an oval-shaped secundum atrial septal defect is reported. The structurally intact device dislodged into the left atrium owing to reversal of transatrial pressure gradients and embolized to the left ventricular outflow tract from where it was retrieved surgically.

Large spontaneous coronary artery dissections-a study of three cases, literature review, and possible therapeutic strategies.

Spontaneous coronary artery dissection is rare, but is now being increasingly recognized as a prominent cause of acute ischemic coronary events occurring usually in relatively young patients, predominantly females. The authors describe the clinical course of 3 patients (1 woman) in whom large spontaneous coronary artery dissections developed. All had diverse clinical presentations;1 presenting with heart failure, the second with post-myocardial infarction angina, and the third with syncope. The second patient underwent coronary angioplasty with multiple overlapping stents while in the other two, it was the considered opinion to continue aggressive medical therapy. The 1-year follow-up was uneventful in all 3 patients. The risk factors ascertained in our patients were diabetes mellitus, smoking, and hypertension.