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BACKGROUND: This study aims to evaluate the role of cancer stem cell marker, CD44, and its ligand HA as potential molecular biomarker for early detection of HNSCC. METHODS AND RESULTS: The expression profile (mRNA/Protein) of CD44 variants were analysed in primary HNSCC lesions and plasma of the patients. Then, prevalence of HA variants was analysed in plasma of the patients. The mRNA expression of CD44 variants, CD44S and CD44v3, were significantly high in both early (stage I/II) and late (stage III/IV) invasive lesions, with predominant expression of CD44v3 in the late-stage lesions. In plasma of HNSCC patients, increased levels of SolCD44, CD44-ICD and unique 62 KD CD44 variants with respect to standard CD44S were seen, in comparison to their prevalence in plasma of normal individuals. The abundance of CD44-ICD and 62 KD variants were significantly high in plasma of late stage HNSCC patients. Interestingly, significantly high level of low molecular weight HA(LMW HA) with respect to high molecular weight HA(HMW HA) was seen in plasma of HNSCC patients irrespective of clinical stages. On the contrary, high HMW HA level in plasma of normal individuals was seen. The high level of LMW HA in plasma of HNSCC patients might be due to combinatorial effect of increased mRNA expression of HA synthesizing enzyme HAS1/2/3 and HA degrading enzyme HYAL1/2, as seen in the primary HNSCC samples. CONCLUSION: Thus, our data revealed the importance of specific CD44 and HA variants in plasma of HNSCC patients during its development as potential non-invasive molecular biomarker of the disease.
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Neoplasias de Cabeça e Pescoço , Ácido Hialurônico , Humanos , Relevância Clínica , Prevalência , Ligantes , Peso Molecular , Carcinoma de Células Escamosas de Cabeça e Pescoço , RNA Mensageiro , Neoplasias de Cabeça e Pescoço/genética , Biomarcadores , Receptores de Hialuronatos/genéticaRESUMO
In an effort to synthesize metallaheteroborane clusters of higher nuclearity, the reactivity of metallaheteroboranes, nido-[(Cp*M)2B6S2H4(CS3)] (Cp* = C5Me5) (1: M = Co; 2: M = Rh) with various metal carbonyls have been investigated. Photolysis of nido-1 and nido-2 with group 6 metal carbonyls, M'(CO)5.THF (M' = Mo or W) were performed that led to the formation of a series of adducts [(Cp*M)2B6S2H4(CS3){M'(CO)5}] (3: M = Co, M' = Mo; 4: M = Co, M' = W; 5: M = Rh, M' = Mo; 6: M = Rh, M' = W) instead of cluster expansion reactions. In these adducts, the S atom of C=S group of di(thioboralane)thione {B2CS3} moiety is coordinated to M'(CO)5 (M = Mo or W) in η1-fashion. On the other hand, thermolysis of nido-1 with Ru3(CO)12 yielded one fused metallaheteroborane cluster [{Ru(CO)3}3S{Ru(CO)}{Ru(CO)2}Co2B6SH4(CH2S2){Ru(CO)3}2S], 7. This 20-vertex-fused cluster is composed of two tetrahedral {Ru3S} and {Ru2B2}, a flat butterfly {Ru3S} and one octadecahedron {Co2RuB7S} core with one missing vertex, coordinated to {Ru2SCH2S2} through two boron and one ruthenium atom. On the other hand, the room temperature reaction of nido-2 with Co2(CO)8 produced one 19-vertex fused metallaheteroborane cluster [(Cp*Rh)2B6H4S4{Co(CO)}2{Co(CO)2}2(µ-CO)S{Co(CO)3}2], 8. Cluster 8 contains one nido-decaborane {Rh2B6S2}, one butterfly {Co2S2} and one bicapped square pyramidal {Co6S} unit that exhibits an intercluster fusion with two sulfur atoms in common. Clusters 3-6 have been characterized by multinuclear NMR and IR spectroscopy, mass spectrometry and structurally determined by XRD analyses. Furthermore, the DFT calculations have been carried out to gain insight into electronic, structural and bonding patterns of the synthesized clusters.
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In an effort to synthesize cobalt-rich metallaheteroboranes from decaborane(14) analogues, we have studied the reaction of 10-vertex nido-[(Cp*Co)2B6H6E2] (Cp* = η5-C5Me5, 1: E = Se and 2: E = Te) with [Co2(CO)8] under thermolytic conditions. All of these reactions yielded face-fused clusters, [(Cp*Co)2B6H6E2{Co(CO)}(µ-CO){Co3(CO)6}] (3: E = Se and 4: E = Te). Further, when clusters 3 and 4 were treated with [Co2(CO)8], they underwent further cluster buildup reactions leading to the formation of 16-vertex doubly face-fused clusters [(Cp*Co)2B6H6E2{Co2(CO)2}(µ-CO)2{Co4(CO)8}] (5: E = Se and 6: E = Te). Cobaltaheteroboranes 3 and 4 comprise one icosahedron {Co4B6E2} and one square pyramidal {Co3B2} moiety, whereas 5 and 6 are made with one icosahedron {Co4B6E2} and two square pyramidal {Co3B2} cores. In an attempt to generate heterometallic metal-rich clusters, we have explored the reactivity of decaborane(14) analogue nido-[(Cp*Co)2B7TeH9] (7) with [Ru3(CO)12] at 80 °C, which afforded face-fused 13-vertex cluster [(Cp*Co)2B7H7Te{Ru3(CO)8}] (8). Cluster 8 is a rare example of a metal-rich metallaheteroborane in which one icosahedron {Co2Ru2B7Te} and a tetrahedron {Ru2B2} units are fused through a common {RuB2} triangular face. Further, the treatment of nido-[(Cp*Co)2B6S2H4(CH2S2)] (9) with [Fe2(CO)9] afforded 11-vertex nido-[(Cp*Co)2B6S2H4(CH2S2){Fe(CO)3}] (10). The core structure of 10 is similar to that of [C2B9H11]2- with a five-membered pentahapto coordinating face. All of the synthesized metal-rich metallaheteroboranes have been characterized by multinuclear nuclear magnetic resonance (NMR) spectroscopy, IR spectroscopy, ESI-MS, and structurally solved by single-crystal X-ray diffraction analysis. Furthermore, theoretical investigations gave insight into the bonding of such higher-nuclearity clusters containing heavier chalcogen atoms.
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The present study has been conducted to investigate the relative changes of carbonaceous aerosols (CA) over a high altitude Himalayan atmosphere with and without (very low) anthropogenic emissions. Measurements of atmospheric organic (OC) and elemental carbon (EC) were conducted during the lockdown period (April 2020) due to global COVID 19 outbreak and compared with the normal period (April 2019). The interesting, unexpected and surprising observation is that OC, EC and the total CA (TCA) during the lockdown (OC: 12.1 ± 5.5 µg m-3; EC: 2.2 ± 1.1 µg m-3; TCA: 21.5 ± 10 µg m-3) were higher than the normal period (OC: 7.04 ± 2.2 µg m-3; EC: 1.9 ± 0.7 µg m-3; TCA: 13.2 ± 4.1 µg m-3). The higher values for OC/EC ratio too was observed during the lockdown (5.7 ± 0.9) compared to the normal period (4.2 ± 1.1). Much higher surface O3 during the lockdown (due to very low NO) could better promote the formation of secondary OC (SOC) through the photochemical oxidation of biogenic volatile organic compounds (BVOCs) emitted from Himalayan coniferous forest cover. SOC during the lockdown (7.6 ± 3.5 µg m-3) was double of that in normal period (3.8 ± 1.4 µg m-3). Regression analysis between SOC and O3 showed that with the same amount of increase in O3, the SOC formation increased to a larger extent when anthropogenic emissions were very low and biogenic emissions dominate (lockdown) compared to when anthropogenic emissions were high (normal). Concentration weighted trajectory (CWT) analysis showed that the anthropogenic activities over Nepal and forest fire over north-east India were the major long-distant sources of the CA over Darjeeling during the normal period. On the other hand, during lockdown, the major source regions of CA over Darjeeling were regional/local. The findings of the study indicate the immense importance of Himalayan biosphere as a major source of organic carbon.
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Utilization of biomass energy from various agricultural wastes for local usages and its removal through open burning potentially increase emission of Green House Gases (GHGs), deteriorate air-quality, formation of tropospheric ozone and create trans-boundary health hazards in countries of South East Asia. The effect of common agro-waste management practices in soil quality and agricultural production system over this part of the world is not well documented. In the present three-years long study, spanning over two entirely different agro-ecological zones of India and Bhutan, highlights the impacts of the burning of agricultural waste in soil physio-chemical properties, biological properties and crop production. The current study also focuses on the alternative usage of crop residue to enhance soil organic carbon, soil moisture, soil nutrients and soil biological activity through the application of biochar and raw agricultural waste generated from the field. It was observed that crop residue used as raw mulch and biochar improved the agricultural production up to 36%-64% over the experimental fields of India and Bhutan. The results from the study disseminated among the local farmers and technological support were provided for practicing alternative crop residue management. Nearly 1450-1500 farmers in India and 100-125 farmers in Bhutan have adopted the agro-waste management practices of removal and re-application of agro-wastes in the field. A total of ~26000 t of CO2 emission has been reduced in two intervention sites during the study period. The present action-research helps to propose future guidelines for environmental friendly crop residue utilization and management and simultaneously help to improve agricultural yield along with soil quality.
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Carbono , Solo , Agricultura , Ásia , Butão , Biomassa , Clima , ÍndiaRESUMO
Efforts are underway to better understand the absorption properties of micro- and nano-sized particles due to their potential in various photonic applications. However, most of these particles exhibit strong scattering in the spectral regions of interest in addition to absorption. Due to strong interference from scattering, the absorption of these turbid samples cannot be directly measured using conventional spectroscopy techniques. The optical properties of these particles are also different from that of the bulk due to quantum confinement and plasmon resonance effects and cannot be inferred from their bulk properties. By measuring the total transmittance and total reflectance (diffuse and collimated) of turbid samples and using an empirical relation between the coefficients of the Kubelka-Munk and radiative transfer theories, we have demonstrated a method to calculate the absorption and reduced scattering coefficients of turbid samples. This method is capable of extracting the absorption coefficient of turbid samples with an error of 2%. Using this method, we have decoupled the specific absorption and specific reduced scattering coefficients of commercially available micro-sized iron oxide particles. The current method can be used to measure the optical properties of irregularly shaped particle dispersions, which are otherwise difficult to estimate theoretically.
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BACKGROUND: Diffusing alpha-emitters Radiation Therapy ("Alpha DaRT") is a new technique that enables the use of alpha particles for the treatment of solid tumors. Alpha DaRT employs interstitial sources carrying a few µ $\mu$ Ci of 224 $^{224}$ Ra below their surface, designed to release a chain of short-lived atoms (progeny of 224 $^{224}$ Ra) which emit alpha particles, along with beta, Auger, and conversion electrons, x- and gamma rays. These atoms diffuse around the source and create-primarily through their alpha decays-a lethal high-dose region measuring a few millimeters in diameter. PURPOSE: While previous studies focused on the dose from the alpha emissions alone, this work addresses the electron and photon dose contributed by the diffusing atoms and by the atoms remaining on the source surface, for both a single Alpha DaRT source and multi-source lattices. This allows to evaluate the low-LET contribution to the tumor dose and tumor cell survival, and demonstrate the sparing of surrounding healthy tissue. METHODS: The low-LET dose is calculated using the EGSnrc and FLUKA Monte Carlo (MC) codes. We compare the results of a simple line-source approximation with no diffusion to those of a full simulation, which implements a realistic source geometry and the spread of diffusing atoms. We consider two opposite scenarios: one with low diffusion and high 212 $^{212}$ Pb leakage, and the other with high diffusion and low leakage. The low-LET dose in source lattices is calculated by superposition of single-source contributions. Its effect on cell survival is estimated with the linear quadratic model in the limit of low dose rate. RESULTS: For sources carrying 3 µ $\umu$ Ci/cm 224 $^{224}$ Ra arranged in a hexagonal lattice with 4 mm spacing, the minimal low-LET dose between sources is â¼ 18 - 30 $\sim 18-30$ Gy for the two test cases and is dominated by the beta contribution. The low-LET dose drops below 5 Gy â¼ 3 $\sim 3$ mm away from the outermost source in the lattice with an effective maximal dose rate of < 0.04 $<0.04$ Gy/h. The accuracy of the line-source/no-diffusion approximation is â¼ 15 % $\sim 15\%$ for the total low-LET dose over clinically relevant distances (2-4 mm). The low-LET dose reduces tumor cell survival by a factor of â¼ 2 - 200 $\sim 2-200$ . CONCLUSIONS: The low-LET dose in Alpha DaRT can be modeled by conventional MC techniques with appropriate leakage corrections to the source activity. For 3 µ $\umu$ Ci/cm 224 $^{224}$ Ra sources, the contribution of the low-LET dose can reduce cell survival inside the tumor by up to two orders of magnitude. The low-LET dose to surrounding healthy tissue is negligible. Increasing source activities by a factor of 5 can bring the low-LET dose itself to therapeutic levels, in addition to the high-LET dose contributed by alpha particles, leading to a "self-boosted" Alpha DaRT configuration, and potentially allowing to increase the lattice spacing.
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Braquiterapia , Neoplasias , Humanos , Neoplasias/radioterapia , Braquiterapia/métodos , Relação Dose-Resposta à Radiação , Partículas alfa/uso terapêutico , Método de Monte CarloRESUMO
The rather low scattering or extinction efficiency of small nanoparticles, metallic and otherwise, is significantly enhanced when they are adsorbed on a larger core particle. But the photoabsorption by particles with varying surface area fractions on a larger core particle is found to be limited by saturation. It is found that the core-shell particle can have a lower absorption efficiency than a dielectric core with its surface partially nucleated with absorbing particles-an "incomplete nanoshell" particle. We have both numerically and experimentally studied the optical efficiencies of titania (TiO2) nucleated in various degrees on silica (SiO2) nanospheres. We show that optimal surface nucleation over cores of appropriate sizes and optical properties will have a direct impact on the applications exploiting the absorption and scattering properties of such composite particles.
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Nanopartículas/química , Fenômenos Ópticos , Absorção , Dióxido de Silício/químicaRESUMO
Energy usage, inequality, and their impacts are deeply intertwined, especially in India. Every year, cooking using biomass-based solid fuel usage causes death to tens of thousands of Indians, specifically, economically unprivileged people. Solid fuel burning has been known as one of the prominent sources of ambient PM2.5 (particulate matter with an aerodynamic diameter of <2.5 µm) concentration in the atmosphere. Thus, limiting the PM2.5 emission from biomass-based cooking fuel through the transition to LPG has gained priority. The government report in India indicates that nearly 8 million households became beneficiaries of the LPG connection through the PMUY scheme till 2019. The transition to clean cooking fuel may have an influence on the ambient PM2.5 concentration. In this study, to explore the nexus between energy inequality and air pollution, we investigated the present status of clean fuel usage in India and its drivers, including the impact of such a massive transition to cleaner fuel on ambient air quality, with a specific focus on PM2.5. The results show an improvement of 15 % in LPG usage from 2015 to 2019 in India., Yet the majority of poorer (>60 %) and poorest communities (>90 %) still use solid biomass as the cooking fuel. No significant correlation (r = 0.036; p-value â« 0.05) was obtained between LPG usage and ambient PM2.5 concentration suggesting the influence of other confounding factors which might subdue the anticipated effect of the usage of clean fuel. The analysis suggests, despite the successful launching of the PMUY, the low LPG usage pattern among the poor, because of the lack of an effective subsidy policy, might jeopardize the effort to fix the standard of ambient air as per WHO.
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BACKGROUND: Diffusing alpha-emitters radiation therapy ("DaRT") is a new method, presently in clinical trials, which allows treating solid tumors by alpha particles. DaRT relies on interstitial seeds carrying µCi-level 224 Ra activity on their surface, which release a chain of short-lived alpha emitters that spread throughout the tumor volume primarily by diffusion. Alpha dose calculations in DaRT are based on describing the transport of alpha emitting atoms, requiring new modeling techniques. PURPOSE: A previous study introduced a simplified framework, the "diffusion-leakage (DL) model," for DaRT alpha dose calculations, and employed it to a point source, as a basic building block of arbitrary configurations of line sources. The aim of this work, which is divided into two parts, is to extend the model to realistic seed geometries (in Part I), and to employ single-seed calculations to study the properties of DaRT seed lattices (Part II). Such calculations can serve as a pragmatic guide for treatment planning in future clinical trials. METHODS: We employ the superposition of single-seed solutions, developed in Part I, to study the alpha dose in DaRT seed lattices and investigate the sensitivity of the required seed activity and spacing to changes in the DL model parameters and to seed placement errors. RESULTS: We show that the rapid fall-off of the dose, which guarantees sparing healthy tissue already 2-3 mm away from the tumor, strongly favors a hexagonal, rather than square, seed placement pattern. Realistic variations in the seed manufacturing parameters (224 Ra activity and emission rate of its daughters) are shown to have a negligible effect on the required lattice spacing. On the other hand, tumor parameters (i.e., diffusion lengths and 212 Pb leakage probability), as well as seed placement errors, have a significant effect. CONCLUSIONS: In most cases, hexagonal lattice spacing on the scale of â¼3.5-4.5 mm using seeds carrying a few µCi/cm 224 Ra will enable overcoming realistic uncertainties in measured tumor environment parameters, as well as seed placement errors, and result in therapeutically relevant alpha dose levels.
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Braquiterapia , Neoplasias , Humanos , Braquiterapia/métodos , Neoplasias/radioterapia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por ComputadorRESUMO
BACKGROUND: Diffusing alpha-emitters Radiation Therapy ("DaRT") is a new method, presently in clinical trials, which allows treating solid tumors by alpha particles. DaRT relies on interstitial seeds carrying µCi-level 224 Ra activity below their surface, which release a chain of short-lived alpha emitters that spread throughout the tumor volume primarily by diffusion. Alpha dose calculations in DaRT are based on describing the transport of alpha emitting atoms, requiring new modeling techniques. PURPOSE: A previous study introduced a simplified framework, the "Diffusion-Leakage (DL) model", for DaRT alpha dose calculations, and employed it to a point source, as a basic building block of arbitrary configurations of line sources. The aim of this work, which is divided into two parts, is to extend the model to realistic seed geometries (in Part I), and to employ single-seed calculations to study the properties of DaRT seed lattices (Part II). Such calculations can serve as a pragmatic guide for treatment planning in future clinical trials. METHODS: We derive a closed-form asymptotic solution for an infinitely long cylindrical source, and extend it to an approximate time-dependent expression that assumes a uniform temporal profile at all radial distances from the source. We then develop a finite-element one-dimensional numerical scheme for a complete time-dependent solution of this geometry and validate it against the closed-form expressions. Finally, we discuss a two-dimensional axisymmetric scheme for a complete time-dependent solution for a seed of finite diameter and length. Different solutions are compared over the relevant parameter space, providing guidelines on their usability and limitations. RESULTS: We show that approximating the seed as a finite line source comprised of point-like segments significantly underestimates the correct alpha dose, as predicted by the full two-dimensional calculation. The time-dependent one-dimensional solution is shown to coincide to sub-percent-level with the two-dimensional calculation in the seed midplane, and maintains an accuracy of a few percent up to â¼2 mm from the seed edge. CONCLUSIONS: For actual treatment plans, the full two-dimensional solution should be used to generate dose lookup tables, similarly to the TG-43 format employed in conventional brachytherapy. Given the accuracy of the one-dimensional solution up to â¼2 mm from the seed edge it can be used for efficient parametric studies of DaRT seed lattices.
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Braquiterapia , Neoplasias , Humanos , Braquiterapia/métodos , Partículas alfa/uso terapêutico , Dosagem Radioterapêutica , Método de Monte CarloAssuntos
Procedimentos Cirúrgicos Cardiovasculares/métodos , Transtornos de Deglutição/etiologia , Síndrome de Cimitarra/complicações , Síndrome de Cimitarra/cirurgia , Anormalidades Múltiplas/cirurgia , Adolescente , Ponte Cardiopulmonar , Dispneia/etiologia , Feminino , Comunicação Interatrial/complicações , Comunicação Interatrial/cirurgia , Humanos , Radiografia Torácica , Síndrome de Cimitarra/diagnóstico por imagem , Esternotomia , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Most of the studies on sunlight-induced pigmentation of skin are mainly focused on ultraviolet (UV) radiation-induced pigmentation and ways to prevent it. Recent studies have shown that the visible component of sunlight can also cause significant skin pigmentation. In the current study, the extent of pigmentation induced by UV and visible regions of sunlight in subjects with Fitzpatrick skin type IV-V was measured and compared with pigmentation induced by total sunlight. The immediate pigment darkening (IPD) induced by the visible fraction of sunlight is not significantly different from that induced by the UV fraction. However, the persistent pigment darkening (PPD) induced by visible fraction of sunlight in significantly lower than that induced by the UV fraction. The dose responses of IPD induced by UV, visible light and total sunlight suggest that both UV and visible light interact with the same precursor although UV is 25 times more efficient in inducing pigmentation per J cm(-2) of irradiation compared to visible radiation. The measured diffused reflection spectra and decay kinetics of UV and visible radiation-induced pigmentation are very similar, indicating that the nature of the transient and persistent species involved in both the processes are also likely to be same.
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Luz , Pigmentação da Pele/efeitos da radiação , Raios Ultravioleta , Adulto , Relação Dose-Resposta à Radiação , Feminino , Humanos , CinéticaRESUMO
Dhokla and idli are popular breakfast foods in India. The objective of the present study was to evaluate their antioxidative properties during different stages of preparation. The effects of fermentation on the enhancement of antioxidative activities were reflected by a higher total phenol content (TPC) in the fermented batters, which also displayed better antioxidative activities than their unfermented batters and steam-cooked products. Fermentation enhanced>2.5-fold TPC and>125% reducing activity. The fermented batters were better free-radical scavengers, which increased in a time and dose-dependent manner, than either the unfermented batters or their steamed products. There was significant enhancement of metal-chelating and lipid peroxidation inhibitory activities during fermentation. The TPCs of both dhokla and idli extracts were positively correlated with the respective values of other parameters, suggesting a possible role of phenolics in the extracts as the antioxidant. The data also revealed a strong correlation between any two of these five parameters tested.
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Antioxidantes/farmacologia , Culinária , Fabaceae/química , Fermentação , Microbiologia de Alimentos , Oryza/química , Fenóis/farmacologia , Quelantes/análise , Quelantes/farmacologia , Grão Comestível/química , Farinha/análise , Farinha/microbiologia , Sequestradores de Radicais Livres , Índia , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sementes/química , VaporRESUMO
For any successful business endeavor, recruitment of required number of appropriately qualified employees in proper positions is a key requirement. For effective utilization of human resources, reorganization of such workforce assignment is also a task of utmost importance. This includes situations when the under-performing employees have to be substituted with fresh applicants. Generally, the number of candidates applying for a position is large and hence, the task of identifying an optimal subset becomes critical. Moreover, a human resource manager would also like to make use of the opportunity of retirement of employees to improve manpower utilization. However, the constraints enforced by the security policies prohibit any arbitrary assignment of tasks to employees. Further, the new employees should have the capabilities required to handle the assigned tasks. In this article, we formalize this problem as the Optimal Recruitment Problem (ORP), wherein the goal is to select the minimum number of fresh employees from a set of candidates to fill the vacant positions created by the outgoing employees, while ensuring satisfiability of the specified security conditions. The model used for specification of authorization policies and constraints is Attribute Based Access Control (ABAC), since it is considered to be the de facto next generation framework for handling organizational security policies. We show that the ORP problem is NP-hard and propose a greedy heuristic for solving it. Extensive experimental evaluation shows both the effectiveness as well as efficiency of the proposed solution.
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Effective utilization of human capital is one of the key requirements for any successful business endeavor, with reorganization necessary if there are nonproductive employees or employees that are retiring. However, while reorganizing tasks for newer employees, it should be ensured that the employees have the requisite capabilities of handling the assigned tasks. Furthermore, security constraints forbid any arbitrary assignment of tasks to employees and also enforce major dependencies on other employees who have access to the same tasks. Since Attribute Based Access Control (ABAC) is poised to emerge as the de facto model for specifying access control policies in commercial information systems, we consider organizational policies and constraints to be modeled with ABAC. Given the increasing size and scale of organizations, both in terms of employees and resources that need to be managed, it is crucial that computational solutions are developed to automate the process of employee to task assignment. In this work, we define the Employee Replacement Problem (ERP) which answers the question of whether a given set of employees can be replaced by a smaller set of employees, while ensuring that the desired security constraints are not violated. We prove that the problem is NP-hard and use CNF-SAT to obtain a solution. An extensive experimental evaluation is carried out on diverse data sets to validate the efficiency of the proposed solution.
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We present a case of tetralogy of Fallot (TOF) accompanied by a type II aorto-pulmonary window with severe pulmonary arterial hypertension in a pediatric patient. A successful repair of tetralogy of Fallot with trans-pulmonary patch closure of aorto-pulmonary window was done.
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Mucormycosis is a rare, life-threatening, angioinvasive opportunistic fungal infection. Most common sites involved are rhino cerebral, pulmonary, cutaneous followed by gastrointestinal. We report a successful management of rare gastrointestinal ileal mucormycosis with perforation peritonitis managed surgically. Later histopathology revealed the ileal mucormycosis with transmural necrotizing inflammation. Histopathological demonstration of the fungus in surgical specimens remains cornerstone of the diagnosis of mucormycosis in view of its non-specific symptoms, low isolation rates of mycological culture and lack of other rapid tests.
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Depletion of chloride from sea-salt aerosols affects their hygroscopicity, cloud condensation nuclei activity as well as microphysical and chemical properties of aerosols and clouds modifying earth-atmosphere radiative balance. Here, we proposed five possible reaction pathways through which the inorganic acids (H2SO4 and HNO3) could deplete chloride from sea-salt aerosols. We determined "maximum potential contribution" (MPC) of each acid and compared the MPC with actual chloride depletion. This step-by-step approach enables us to identify the most preferable reaction pathway(s) for coarse, superfine, accumulation and ultrafine aerosols over a Himalayan station (Darjeeling), a tropical urban station (Kolkata) and a tropical mangrove forest at the north-east coast of Bay of Bengal (Sundarban) in India. Over Kolkata and Darjeeling, locally generated acids reacted with transported sea-salts. Over Sundarban, the locally generated sea-salts from the Bay of Bengal reacted with the acids of biomass burning plume transported from Eastern Ghat and continental haze transported from upper Indo-Gangetic Plain. The average chloride depletion in PM10 ranged between 70 and 74% over Sundarban and 31-34% over Kolkata and Darjeeling. We observed that HNO3(g) depleted the larger (>1 µm) chlorides whereas H2SO4(g) depleted the smaller (<1 µm) chlorides over Kolkata and Darjeeling. However, in addition to H2SO4(g) and HNO3(g), some other species could be involved in chloride depletion over Sundarban mainly during winter. The study reveals that Sundarban acts as the major sink of the inorganic acids transported from Eastern Ghat biomass burning plume inhibiting their further advection towards inland regions.
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Poluentes Atmosféricos/análise , Cloretos/isolamento & purificação , Monitoramento Ambiental/métodos , Clima Tropical , Áreas Alagadas , Aerossóis/análise , Poluentes Atmosféricos/isolamento & purificação , Altitude , Atmosfera/química , Biomassa , Índia , Tamanho da Partícula , Estações do Ano , UrbanizaçãoRESUMO
Preserved melanin pigments have been discovered in fossilised integumentary appendages of several amniote lineages (fishes, frogs, snakes, marine reptiles, non-avialan dinosaurs, birds, and mammals) excavated from lagerstätten across the globe. Melanisation is a leading factor in organic integument preservation in these fossils. Melanin in extant vertebrates is typically stored in rod- to sphere-shaped, lysosome-derived, membrane-bound vesicles called melanosomes. Black, dark brown, and grey colours are produced by eumelanin, and reddish-brown colours are produced by phaeomelanin. Specific morphotypes and nanostructural arrangements of melanosomes and their relation to the keratin matrix in integumentary appendages create the so-called 'structural colours'. Reconstruction of colour patterns in ancient animals has opened an exciting new avenue for studying their life, behaviour and ecology. Modern relationships between the shape, arrangement, and size of avian melanosomes, melanin chemistry, and feather colour have been applied to reconstruct the hues and colour patterns of isolated feathers and plumages of the dinosaurs Anchiornis, Sinosauropteryx, and Microraptor in seminal papers that initiated the field of palaeocolour reconstruction. Since then, further research has identified countershading camouflage patterns, and informed subsequent predictions on the ecology and behaviour of these extinct animals. However, palaeocolour reconstruction remains a nascent field, and current approaches have considerable potential for further refinement, standardisation, and expansion. This includes detailed study of non-melanic pigments that might be preserved in fossilised integuments. A common issue among existing palaeocolour studies is the lack of contextualisation of different lines of evidence and the wide variety of techniques currently employed. To that end, this review focused on fossil amniotes: (i) produces an overarching framework that appropriately reconstructs palaeocolour by accounting for the chemical signatures of various pigments, morphology and local arrangement of pigment-bearing vesicles, pigment concentration, macroscopic colour patterns, and taphonomy; (ii) provides background context for the evolution of colour-producing mechanisms; and (iii) encourages future efforts in palaeocolour reconstructions particularly of less-studied groups such as non-dinosaur archosaurs and non-archosaur amniotes.