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1.
Cureus ; 16(4): e58679, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38774168

RESUMEN

Tumors that develop on the chest wall are usually rare. This case report highlights a rare occurrence of a giant cell tumor originating from the anterior arch of the fourth rib. The patient, a 21-year-old male, presented with a bulging mass that had been gradually increasing in size over an eight-month period, reaching dimensions of 12 x 8 cm. Despite the noticeable swelling, the patient reported no associated pain or discomfort and denied any history of weight loss or trauma. The absence of chest pain or cardiovascular symptoms distinguished this case from other chest wall pathologies. This report underscores the importance of considering rare entities such as giant cell tumors in the differential diagnosis of chest wall masses, especially in cases where clinical presentation and patient history do not align with more common conditions.

2.
Cureus ; 16(4): e58157, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38741800

RESUMEN

This case report describes an unusual presentation of schwannoma, a typically benign and solitary tumor originating from Schwann cells in peripheral nerves. While the literature on extraspinal schwannomas is limited, this report discusses the case of a 21-year-old female with complaint of a back swelling persisting for two years, causing discomfort during sleep. The oval-shaped swelling, measuring 7x6 cm, was located over the T11-T12-L1 vertebrae, with normal overlying skin, pinchable hardness, and fixation to the vertebrae. The patient had no history of pain or weakness in the lower limbs. Fine-needle aspiration cytology (FNAC) yielded inconclusive results. X-ray imaging of the thoracolumbar spine revealed a soft tissue shadow over the T11-T12-L1 vertebrae. The patient underwent complete surgical excision through a vertical incision, emphasizing the importance of preoperative imaging for accurate diagnosis, optimal surgical planning, and ensuring procedural safety.

3.
Environ Pollut ; 343: 123246, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38158012

RESUMEN

This study reports size-resolved dithiothreitol (DTT)-based oxidative potential (OP: total and water-soluble) in rural kitchens using liquefied petroleum gas (LPG), firewood (FW), and mixed biomass (MB) fuels in northeastern (NE) India. In comparison to LPG, volume-normalized total OP (OPtotal(v)DTT) was enhanced by a factor of ∼5 in biomass-using kitchens (74 ± 35 to 78 ± 42 nmol min-1 m-3); however, mass-normalized total OP (OPtotal(m)DTT) was similar between LPG and FW users and higher by a factor of 2 in MB-using kitchens. The water-insoluble OP (OPwi(v, m)DTT) fraction in OPtotal(v, m)DTT was greater than 50% across kitchens. Size distributions across kitchens and OPDTT categories ranged from unimodal to trimodal. OPws(v)DTT was driven by metals as well as organics across size fractions while OPwi(v)DTT was majorly constrained by metals with an increasing importance of organics in fine particles of biomass-using kitchens. Multiple linear regression analysis revealed that Cu and Ba explained 71% of the OPtotal(v)DTT variability in LPG-using kitchens, while water-soluble organic carbon (WSOC) and Ba were responsible for 44% variability in FW-using kitchens. Finally, the high internal dose of OPtotal(v)DTT (28-31 nmol min-1 m-3) in biomass-using kitchens established the severity of oxidative stress on the exposed population.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Petróleo , Material Particulado/análisis , Contaminantes Atmosféricos/análisis , India , Aerosoles , Estrés Oxidativo , Ditiotreitol , Agua , Monitoreo del Ambiente , Contaminación del Aire Interior/análisis
5.
Sci Total Environ ; 905: 167163, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37730065

RESUMEN

Exposure to a total of 51 targeted and non-targeted polycyclic aromatic hydrocarbons (PAHs) and their oxygenated and alkylated derivatives associated with size-segregated aerosol was investigated in rural kitchens using liquefied petroleum gas (LPG), mixed biomass (MB) and firewood (FW) fuels in northeastern India. The averaged PM10-associated parent-, alkylated-, and oxygenated-PAHs concentrations increased notably from LPG (257, 54, and 116 ng m-3) to MB (838, 119, and 272 ng m-3) to FW-using kitchens (2762, 225, and 554 ng m-3), respectively. PAHs were preferentially associated with the PM1 fraction with contributions increasing from 80 % in LPG to 86 % in MB and 90 % in FW-using kitchens, which in turn was dominated by <0.25 µm particles (54-75 % of the total). A clear profile of enrichment of low-molecular weight PAHs in cleaner fuels (LPG) and a contrasting enrichment of high-molecular weight PAHs in biomass-based fuels was noted. The averaged internal dose of Benzo[a]pyrene equivalent was the lowest in the case of LPG (19 ng m-3), followed by MB (161 ng m-3) and the highest in FW users (782 ng m-3). Estimation of incremental lifetime cancer risk (ILCR) from PAH exposure revealed extremely high cancer risk in biomass users (factors of 8-40) compared to LPG. The potential years of life lost (PYLL) and PYLL rate averaged across kitchen categories was higher for lung cancer (PYLL: 10.55 ± 1.04 years; PYLL rate: 204 ± 426) compared to upper respiratory tract cancer (PYLL: 10.02 ± 0.05 years; PYLL rate: 4 ± 7), and the PYLL rates for biomass users were higher by factors of 9-56 as compared to LPG users. These findings stress the need for accelerated governmental intervention to ensure a quick transition from traditional biomass-based fuels to cleaner alternatives for the rural population of northeastern India.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Neoplasias Pulmonares , Petróleo , Hidrocarburos Policíclicos Aromáticos , Humanos , Población Rural , Contaminación del Aire Interior/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Culinaria , India , Costo de Enfermedad , Material Particulado/análisis , Contaminantes Atmosféricos/análisis
6.
Sci Total Environ ; 875: 162539, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36871731

RESUMEN

Mass-size distribution of respirable aerosol and 13 associated trace elements (TEs) were investigated in rural kitchens using liquefied petroleum gas (LPG), firewood and mixed biomass fuels across three northeastern Indian states. The averaged PM10 (particulate matter with aerodynamic diameter ≤ 10 µm) and ΣTE concentrations were 403 and 30 µg m-3 for LPG, 2429 and 55 µg m-3 for firewood, and 1024 and 44 µg m-3 for mixed biomass-using kitchens. Mass-size distributions were tri-modal with peaks in the ultrafine (0.05-0.08 µm), accumulation (0.20-1.05 µm), and coarse (3.20-4.57 µm) modes. Respiratory deposition, estimated using the multiple path particle dosimetry model, ranged from 21 % to 58 % of the total concentration across fuel types and population age categories. Head, followed by pulmonary and tracheobronchial, was the most vulnerable deposition region, and children were the most susceptible age group. Inhalation risk assessment of TEs revealed significant non-carcinogenic as well as carcinogenic risk, especially for biomass fuel users. The potential years of life lost (PYLL) was the highest for chronic obstructive pulmonary disease (COPD: 15.9 ± 3.8 years) followed by lung cancer (10.3 ± 0.3 years) and pneumonia (10.1 ± 0.1 years), while the PYLL rate was also highest for COPD, with Cr(VI) being the major contributor. Overall, these findings reveal the significant health burden faced by the northeastern Indian population from indoor cooking using solid biomass fuels.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Petróleo , Enfermedad Pulmonar Obstructiva Crónica , Oligoelementos , Niño , Humanos , Monitoreo del Ambiente , Aerosoles y Gotitas Respiratorias , Material Particulado/análisis , Culinaria , India , Contaminación del Aire Interior/análisis , Costo de Enfermedad , Contaminantes Atmosféricos/análisis
7.
Environ Geochem Health ; 45(5): 2447-2460, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35995879

RESUMEN

The study attempts to look into the morphological characteristics, elemental composition, contamination, source contributions, and associated health risks in household dust of Napaam, a rural region in the Brahmaputra flood plain in North East India. Morphological evidence suggests that most of the house dust particles were sourced from vehicle abrasion and soil. Three contamination indices-enrichment factor (EF), index of geo-accumulation (Igeo), and pollution load index (PLI) indicated that Cl and four trace elements (Cu, Zn, As, and Pb) are significantly enriched in house dust with extreme pollution load. Principal component analysis (PCA) and positive matrix factorization (PMF) revealed 3 potential major sources of elements in house dust-traffic + re-suspension of road dust (35.8%), soil dust (22.2%), and river sediment deposit (16.4%). Two minor sources-biomass burning (13.3%), and construction activities (12.3%) were also identified. Based on health risk assessment (HRA), both children and adult were found to be susceptible to non-carcinogenic and carcinogenic risks.


Asunto(s)
Polvo , Metales Pesados , Adulto , Niño , Humanos , Polvo/análisis , Monitoreo del Ambiente , Metales Pesados/análisis , Medición de Riesgo , Suelo , China , Ciudades
8.
Ann Afr Med ; 22(4): 537-543, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38358158

RESUMEN

Introduction: Resection of pancreatic tissue is necessary for many pancreatic diseases. The most common form of cancer, pancreatic duct adenocarcinoma, manifests with early metastases and is thought to be resistant to other currently known treatment regimens. Such tumors present a complex and difficult management and handling challenge for a surgeon. Surgical resection affords a better prognosis with a median survival of 14-20 months following resection and up to 25% 5-year survival rates. In this study, data from 75 pancreatic resections for diverse malignant pancreatic lesions will be presented. Methods: At a teaching institute in Central India, this ongoing longitudinal study began in 2009 and was carried on till 2018. Only 75 of the 122 patients who underwent pancreatic resection were deemed appropriate for the current study. All patients were thoroughly examined after being admitted before being given the option of surgery. There were 22 female patients and 53 male patients. The age range for the group was 34-67 years. Results from a range of different malignancies and various pancreatic resection procedures are presented in this study. Results: One of the most aggressive cancers, pancreatic adenocarcinoma, responds to surgical treatment better than other alternative techniques. Out of 75 patients in our series, 32 had pancreatic head cancer, 28 had periampullary cancer, 2 had duodenal cancer, 8 had distal cholangiocarcinoma, and 1 had mucin-producing cystadenocarcinoma. Four patients had pancreatic cancer in both the body and tail. Fifty-three men and 22 women, ages 34-67 years, Whipple's operation and distal pancreatectomy were the most frequent procedures. In our series, survival ranged from 18 to 24 months, and the 5-year survival rate was 12%, which is primarily seen with periampullary carcinoma. Conclusion: The sole option for long-term survival or a cure for pancreatic cancer is surgery. Chemoradiation is ineffective as a first line of treatment. However, some reports contend that palliative chemotherapy actually improves the quality of life. The biology of the illness rules and determines the result; the kind of surgery performed had no bearing on survival, morbidity, or fatality. Context: The above study was taken up in the context of - pancreatic tumors and pathological types, how imaging helps in deciding the plan of surgical management without biopsy. Outcomes of pancreatic resections for pancreatic cancer. Settings and Design: In a suburban hospital which is a tertiary care center, this longitudinal prospective study was conducted from 2009 to 2018.


Résumé Introduction: La résection du tissu pancréatique est nécessaire pour de nombreuses maladies pancréatiques. La forme de cancer la plus courante, l'adénocarcinome du canal pancréatique, se manifeste par des métastases précoces et on pense qu'elle est résistante aux autres schémas thérapeutiques actuellement connus. De telles tumeurs présentent un défi de gestion et de manipulation complexe et difficile pour un chirurgien. La résection chirurgicale offre un meilleur pronostic avec une survie médiane de 14 à 20 mois après la résection et jusqu'à 25 % de taux de survie à 5 ans. Dans cette étude, les données de 75 résections pancréatiques pour diverses lésions pancréatiques malignes seront présentées. Méthodes: Dans un institut d'enseignement du centre de l'Inde, cette étude longitudinale en cours a débuté en 2009 et s'est poursuivie jusqu'en 2018. Seuls 75 des 122 patients ayant subi une résection pancréatique ont été jugés appropriés pour l'étude actuelle. Tous les patients ont été soigneusement examinés après leur admission avant de pouvoir subir une intervention chirurgicale. Il y avait 22 patients de sexe féminin et 53 patients de sexe masculin. La tranche d'âge du groupe était de 34 à 67 ans. Les résultats d'une gamme de différentes tumeurs malignes et de diverses procédures de résection pancréatique sont présentés dans cette étude. Résultats: L'un des cancers les plus agressifs, l'adénocarcinome du pancréas, répond mieux au traitement chirurgical que les autres techniques alternatives. Sur les 75 patients de notre série, 32 avaient un cancer de la tête du pancréas, 28 un cancer périampullaire, un cancer duodénal, 8 un cholangiocarcinome distal et 1 un cystadénocarcinome producteur de mucine. Quatre patients présentaient un cancer du pancréas au niveau du corps et de la queue. Cinquante-trois hommes et 22 femmes, âgés de 34 à 67 ans, l'opération de Whipple et la pancréatectomie distale étaient les procédures les plus fréquentes. Dans notre série, la survie variait de 18 à 24 mois et le taux de survie à 5 ans était de 12 %, ce qui est principalement observé dans le carcinome périampullaire. Conclusion: La seule option pour survivre à long terme ou guérir le cancer du pancréas est la chirurgie. La chimioradiothérapie est inefficace en première intention. Cependant, certains rapports affirment que la chimiothérapie palliative améliore réellement la qualité de vie. La biologie de la maladie gouverne et détermine le résultat ; le type d'intervention chirurgicale pratiquée n'avait aucune incidence sur la survie, la morbidité ou le décès. Contexte: L'étude ci-dessus a été reprise dans le contexte des tumeurs pancréatiques et des types pathologiques, comment l'imagerie aide à décider du plan de prise en charge chirurgicale sans biopsie. Résultats des résections pancréatiques pour le cancer du pancréas. Paramètres et conception: Dans un hôpital de banlieue qui est un centre de soins tertiaires, cette étude prospective longitudinale a été menée de 2009 à 2018. Mots-clés: Complications, résections pancréatiques, résultats.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Adenocarcinoma/cirugía , Adenocarcinoma/patología , Estudios Longitudinales , Estudios Prospectivos , Calidad de Vida , Hospitales
9.
Chemosphere ; 305: 135490, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35760126

RESUMEN

This study employs ISORROPIA-II for the evaluation of aerosol acidity and quantification of contributions from chemical species and meteorological parameters to acidity variation in the Indian context. PM2.5 samples collected during summer (April-July 2018), post-monsoon (September-November 2018), and winter (December 2018-January 2019) from a rural receptor location in the eastern Indo-Gangetic Plain (IGP) were analyzed for ionic species, water-soluble organic carbon (WSOC), and organic and elemental carbon (OC, EC) fractions. This was followed by estimation of the in situ aerosol pH and liquid water content (LWC) using the forward mode of ISORROPIA-II, which is less sensitive to measurement uncertainty compared to the reverse mode, for a K+-Ca2+-Mg2+-NH4+-Na+-SO42--NO3--Cl--H2O system. Aerosol pH was moderately acidic (summer: 2.93 ± 0.67; post-monsoon: 2.67 ± 0.23; winter: 3.15 ± 0.34) and was most sensitive to SO42- and total ammonium (TNH3) variation. The LWC of aerosol showed an increasing trend from summer (16.6 ± 13.6 µg m-3) through winter (32.9 ± 10.4 µg m-3). With summer as the baseline, the largest changes in aerosol pH during the other seasons was driven by SO42- (ΔpH: -0.70 to -0.82 units), followed by TNH3 (ΔpH: +0.25 to +0.38 units) with K+ and temperature being significant only during winter (ΔpH: +0.51 and + 0.46 units, respectively). The prevalent acidity regime provided three major insights: i) positive summertime Cl- depletion (49 ± 20%) as a consequence of SO42- substitution increased aerosol pH by 0.03 ± 0.20 units and decreased LWC by 2.4 ± 5.9 µg m-3; ii) the rate of strong acidity (H+str) neutralization and the [H+str]/[SO42-] molar ratio suggested the existence of bounded acidity in ammonium-rich (winter) conditions; and iii) significant correlations between LWC, WSOC, and secondary organics during post-monsoon and winter pointed towards a possible indirect role of WSOC in enhancing LWC of aerosol, thereby increasing pH. Given the inability of proxies such as H+str and charge ratios to accurately represent aerosol pH as demonstrated here, this study emphasizes the need for rigorous thermodynamic model-based evaluation of aerosol acidity in the Indian scenario.


Asunto(s)
Contaminantes Atmosféricos , Compuestos de Amonio , Ácidos/análisis , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Compuestos de Amonio/análisis , Carbono/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Agua/análisis
10.
Environ Sci Pollut Res Int ; 29(26): 40252-40261, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35404032

RESUMEN

We hypothesize that firework events involving the combustion of charcoal fuel, organic binders, metal salts, and cellulose-based wrapping material could be significant transient sources of aerosol brown carbon (BrC). To test this, we couple high time-resolution (1 min) measurements of black carbon (BC) and BrC absorption from a 7-wavelength aethalometer with time-integrated (12-24 h) measurements of filter extracts, i.e., UV-visible, fluorescence, and Fourier-transformed infrared (FT-IR) signatures of BrC, total and water-soluble organic carbon (OC and WSOC), ionic species, and firework tracer metals during a sampling campaign covering the Diwali fireworks episode in India. In sharp contrast to BC, BrC absorption shows a distinct and considerable rise of 2-4 times during the Diwali period, especially during the hours of peak firework activity, as compared to the background. Fluorescence profiles suggest enrichment of humic-like substances (HULIS) in the firework plume, while the enhancement of BrC absorption in the 400-500 nm range suggests the presence of nitroaromatic compounds (NACs). Considerable contributions of WSOC and secondary organics to OC (44.1% and 31.2%, respectively) and of the water-soluble fraction of BrC to total BrC absorption (71.0%) during the Diwali period point toward an atmospherically processed, polar signature of firework-related BrC, which is further confirmed by FT-IR profiles. This aqueous BrC exerts a short-lived but strong effect on atmospheric forcing (12.0% vis-à-vis BC in the UV spectrum), which could affect tropospheric chemistry via UV attenuation and lead to a stabilization of the post-Diwali atmosphere, resulting in enhanced pollutant build-up and exposure.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Monitoreo del Ambiente/métodos , Sustancias Húmicas/análisis , Material Particulado/análisis , Hollín , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química
11.
Sci Total Environ ; 705: 135805, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-31972942

RESUMEN

This work reports the first assessment of contamination levels, source contributions and health risks associated with heavy metals (HMs) in road dust from Kolkata, the second-most polluted metropolis in India. To this end, samples collected from 57 locations across 6 land-use categories: residential, roadside, traffic, railway, port and industrial areas in the city during 2018 were analyzed for 11 major and trace metals (Ca, Mg, Fe, Al, Mn, Ni, V, Cu, Zn, Cr, Pb) in three size fractions: <75 µm, 75-125 µm and 125-300 µm. Overall, Mn, Zn, Cr, Pb, V, Cu and Ni were enriched in the smallest fraction by factors of 1.2-2.7. Based on metal distribution across land-use categories, crustal dust (Fe, Al, V), construction activities (Ca, Mg), metallurgical processes (Pb), and non-exhaust abrasive emissions from brake, tire and paint wear (Cu, Zn, Cr) were found to be significant. HMs such as Cu, Zn, Cr and Pb were considerably enriched over background levels as suggested by three contamination indices: Enrichment Factor (EF; overall range: 2.4-12.0), Index of Geo-accumulation (Igeo; overall range: 1.1-3.4), and Pollution Index (PI; overall range: 3.1-15.6). Geospatial mapping identified HM contamination hotspots (integrated PI >4) in west-central and northern parts (the older sections) of the city represented by industrial, port, and traffic-congested residential areas. Using positive matrix factorization (PMF), the following sources were apportioned for the three size fractions: crustal dust (48-66%), construction activities (18-20%), vehicular abrasion (7-21%), industrial emissions (5-8%), a Cr-dominated mixed source (6%) and an unassigned source (7%). Finally, health risk assessment in the form of cumulative hazard index (HI) and incremental lifetime cancer risk (ILCR) found that children (mean HIchildren: 1.29 and ILCRchildren: 2E-04) are comparatively more vulnerable than adults (mean HIadults: 0.22 and ILCRadults: 8E-05) to HM exposure, with the ingestion exposure pathway dominating over dermal contact and inhalation.


Asunto(s)
Polvo , Adulto , Niño , China , Ciudades , Monitoreo del Ambiente , Humanos , India , Metales Pesados , Medición de Riesgo
12.
Arch Dermatol Res ; 311(10): 773-793, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31432208

RESUMEN

In the present study resveratrol nanoemulsion gel was developed and optimized with the aim of enhancing the permeability and antioxidant activity against ultraviolet (UV)-induced oxidative skin damage. Droplet size, polydispersity index, drug permeation flux, permeability coefficient and drug deposition in skin of resveratrol-loaded nanoemulsion were found to be 65.00 ± 5.00 nm, 0.171 ± 0.082, 144.50 µg/cm2/h, 2.90 × 10-2 cm/h and 45.65 ± 4.76%, respectively, whereas drug permeation flux, permeability coefficient and drug deposition in skin from nanoemulsion gel were found to be 107.70 µg/cm2/h, 2.06 × 10-2 cm/h and 62.65 ± 4.98%, respectively. Confocal studies depicted deeper penetration of resveratrol from nanoemulsion gel. Differential scanning calorimetry and Fourier-transform infrared spectrophotometer studies confirmed that nanoemulsion gel enhanced fluidization of stratum corneum lipids and conformational disruption of lipid bilayer, thereby enhancing skin permeation of resveratrol. Histopathology study of skin revealed that resveratrol-loaded nanoemulsion gel inhibited UV-induced spongosis, edema and epidermal hyperplasia response. Levels of glutathione, superoxide dismutase, catalase and protein carbonyl in the skin of UV-irradiated rats were significantly (p < 0.01) improved in the skin of animals treated with nanoemulsion gel. Experimental results suggested that nanoemulsion gel could be explored as a promising carrier for topical delivery of resveratrol for prevention of UV-induced oxidative skin damage owing to its enhanced permeability and retention effect.


Asunto(s)
Antioxidantes/administración & dosificación , Portadores de Fármacos/química , Resveratrol/administración & dosificación , Piel/efectos de los fármacos , Rayos Ultravioleta/efectos adversos , Administración Cutánea , Animales , Emulsiones , Geles , Masculino , Modelos Animales , Nanoestructuras/química , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/efectos de la radiación , Permeabilidad , Ratas , Piel/metabolismo , Piel/efectos de la radiación
13.
Environ Manage ; 63(6): 777-788, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31001656

RESUMEN

The objective of this research is to examine how protected area size influences the conservation benefit and acquisition cost of creating a protected area, how the resulting effects influence the predicted rate of return on investment (ROI), and how those relationships change prioritization decision-making for selecting protected areas compared with decisions based only on conservation benefit and decisions based only on acquisition cost. The objective is accomplished in an econometric framework by analyzing the parcel-level acquisition cost and conservation benefit measured by the change in potential fragmentation patterns on the landscape resulting from protection. We focus on areas acquired by The Nature Conservancy in central and southern Appalachia, United States. As an indicator of the change in landscape fragmentation, we use a fragmentation statistic known as effective mesh size. Although the effect of protected parcel size on predicted ROI is inelastic, greater conservation effectiveness is obtained with larger protected parcels than with smaller ones on average. Protected parcel size influences parcels' rankings for protection more (less) when only the predicted change in effective mesh size of protected area (only the predicted acquisition cost per area) is used for prioritizing parcels than when the ranking of parcels is determined by the predicted ROI. These findings imply that, although protected parcel size is important, failure to prioritize using ROI could result in an inappropriate level of emphasis being given to protected parcel size than is warranted.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Región de los Apalaches , Costos y Análisis de Costo , Inversiones en Salud , Estados Unidos
14.
Data Brief ; 21: 2063-2074, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30533453

RESUMEN

The dataset provided in this article are related to the research article entitled "The Journey of Universal Hybrid-pi model-from its Inception to Experimental Validation and its impact on Analog Circuit Design" (Sharma, in press). While analyzing dataset of the incremental output impedances of the BJT Current Sources, Conventional Hybrid-pi model, and Unilateral Model grossly underestimate the output impedances whereas Universal Hybrid-pi Model gives a much larger range of output impedances from ro to 40ro. The quest for these enhanced prediction led to the discovery of "Variable Latching Effect" (Sharma, 1990). Furthermore the ascending order of the dataset of Break-over voltages of Device-under-Test (DUT) were obeyed by the dataset predictions of incremental output impedance by Universal Model but not obeyed by those made by Conventional Model and Unilateral model. Direct experimental measurement of output impedances of current sources using laboratory setup validated Universal Hybrid-pi Model (Sharma, 2003) [3] but the results were inconclusive. The experimental measurement of the incremental output impedances by a Professional setup was also done and verified by analytical results. All incremental analysis is carried out at a given Q-point and Q-point decides the incremental parameters of the Hybrid-pi model and T-model which are to be used in the analytic relations (2), (3) and (4) given in the main text (Sharma, in press). Q-points of the current sources at which the output impedance measurement have been made are given in this dataset (see Table 6). Model parameters at the given Q-points are derived from simple analytic relations given in the main text (Sharma, in press) and tabulated in Table 7 and Table 7A. The theoretical incremental output impedance are calculated for the conventional model, universal model and T-model and compared with the experimentally measured values of output impedance and tabulated in this dataset (see Table 8 and Figure 8). A very high gain Differential Amplifier׳s incremental voltage gain is experimentally measured and analytically verified. The experimental values and Universal Hybrid-pi model theoretical analytic results are given . The conventional model analytic results for incremental voltage gains are also tabulated. This article data is being made publicly available to enable critical or extended analysis.

15.
Int Sch Res Notices ; 2014: 648294, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-27419213

RESUMEN

Rapid line probe assay (LPA) can be a practical and rapid alternative to the slow conventional phenotypic drug susceptibility testing (DST) for detection of drug resistant tuberculosis (TB). The purpose of this study is to determine the diagnostic accuracy of Genotype MTBDRplus, LPA for TB, and compare its performance with conventional DST. A total of 54 culture samples were analyzed for DST using both conventional proportion method and MTBDRplus, where conventional DST identified 43 isolates (79.6%) as drug resistant. Among these 43 drug resistant isolates, 30 isolates (69.7%) were found to be multidrug resistant (MDR). Of all observed mutations using MTBDRplus, codon 531 of rpoB gene and codon 315 of katG gene were found to have highest mutational frequency for RIF resistance (64.7%) and INH resistance (96.8%), respectively. In the present study, MTBDRplus assay was shown to have excellent specificity (100%) for both RIF and INH resistance while sensitivity of the assay was little lower with value of 89.4% for RIF resistance and 91.4% for INH resistance. Therefore, the assay can be a rapid, reliable, and promising molecular test for early detection of MDR-TB in Nepal.

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