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1.
Environ Monit Assess ; 196(6): 557, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38764082

RESUMEN

It is vital to keep an eye on changes in climatic extremes because they set the stage for current and potential future climate, which usually have a reasonable adverse impact on ecosystems and society. The present study examines the variability and trends in precipitation and temperature across seasons in the Kinnaur district, offering valuable insights into the complex dynamics of the Himalayan climate. Using Climatic Research Unit gridded Time Series (CRU TS) datasets from 1951 to 2021, the study analyzes the data to produce 28 climate indices based on India Meteorological Department (IMD) convention indices and Expert Team on Climate Change Detection and Indices (ETCCDI). Although there may be considerable variation in climate indices in terms of absolute values within different products, there is consensus in both long-term trends and inter-annual variability. Analysis shows that even within a small area, there is variability in the magnitude and direction of historic temperature trends. Initially, the data were subjected to rigorous quality control procedures, which involved identifying anomalies. Statistical analysis like trend analysis, employing Mann-Kendall test and Sen's slope estimator, reveal significant (p < 0.05) increase in consecutive dry days (CDD) at 0.03 days/year and decrease in consecutive wet days (CWD) at 0.02 days/year. Notably, the frequency of heavy precipitation occurrences showed an increasing trend. Changes in precipitation in the Western Himalaya are driven by a complex interplay of orographic effects, monsoonal dynamics, atmospheric circulation patterns, climate change, and localized factors such as topography, atmospheric circulation patterns, moisture sources, land-sea temperature contrasts, and anthropogenic influences. Moreover, in case of temperature indices, there is significant increasing trend observed. Temperature indices indicate a significant annual increase in warm nights (TN90p) at 0.06%/year and warm days (TX90p) at 0.11%/year. Extreme temperature events have been trending upward, with monthly daily maximum temperature (TXx) increasing by 1.5 °C yearly. This study enhances our comprehension of the global warming phenomenon and underscores the importance of acknowledging alterations in the water cycle and their repercussions on hydrologic resources, agriculture, and livelihoods in the cold desert of the northwestern Indian Himalaya.


Asunto(s)
Cambio Climático , Monitoreo del Ambiente , India , Monitoreo del Ambiente/métodos , Estaciones del Año , Lluvia , Temperatura , Clima
2.
PLoS One ; 17(6): e0269673, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35714160

RESUMEN

Climate variability coupled with anthropogenic pressures is the most critical driver in the Himalayan region for forest ecosystem vulnerability. Dactylorhiza hatagirea (D.Don) Soo is an important yet highly threatened medicinal orchid from the Himalayan region. Poor regenerative power and growing demand have resulted in the steep decline of its natural habitats populations. The present study aims to identify the habitat suitability of D. hatagirea in the Western Himalaya using the maximum entropy model (MaxEnt). The community climate system model (CCSM ver. 4) based on representative concentration pathways (RCPs) was used to determine suitable future areas. Sixteen least correlated (< 0.8) bioclimatic, topographical and geomorphic variables were used to construct the species climatic niche. The dominant contributing variables were elevation (34.85%) followed by precipitation of the coldest quarter (23.04%), soil type (8.77%), land use land cover (8.26%), mean annual temperature (5.51%), and temperature seasonality (5.11%). Compared to the present distribution, habitat suitability under future projection, i.e., RCP 4.5 and RCP 8.5 (2050 and 2070), was found to shift to higher elevation towards the northwest direction, while lower altitudes will invariably be less suitable. Further, as compared to the current distribution, the climatic niche space of the species is expected to expand in between11.41-22.13% in the near future. High habitats suitability areas are mainly concentrated in the forest range like Dharchula and Munsyari range, Pindar valley, Kedarnath Wildlife Sanctuary, West of Nanda Devi Biosphere Reserve, and Uttarkashi forest division. The present study delineated the fundamental niche baseline map of D. hatagirea in the Western Himalayas and highlighted regions/areas where conservation and management strategies should be intensified in the next 50 years. In addition, as the species is commercially exploited illegally, the information gathered is essential for conservationists and planners who protect the species at the regional levels.


Asunto(s)
Cambio Climático , Ecosistema , Conservación de los Recursos Naturales , Bosques , Suelo
3.
Cardiovasc Revasc Med ; 21(4): 501-507, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31377129

RESUMEN

BACKGROUND: Percutaneous coronary intervention (PCI) outcomes for patients with significant calcification have been consistently inferior compared to patients without significant calcification. Procedural success and long-term outcomes after PCI have been worse in patients with severe coronary calcium. OBJECTIVE: A Bayesian meta-analysis of outcomes comparing rotational atherectomy (RA) with orbital atherectomy (OA) was performed. METHODS: PubMed, Embase, and Cochrane Library databases were searched through 30th November 2018 and identified 4 observational studies. RESULTS: The primary end-point, Major Adverse Cardiac Event (MACE) composing of death, MI and stroke at 1 year was more likely with RA (OR = 1.61; 95% CI: 1.11-2.33; p = 0.01) as compared to OA. The driver of the difference in MACE between the two groups was a statistically significant difference in mortality favoring OA (OR = 4.65; 95% CI: 1.36-15.87; p = 0.01). Peri-procedural MI, the other component of the primary end-point was 1.3 times more likely in the RA arm (OR = 1.35; 95% CI 0.95-1.92; p-0.09) and was not statistically different between the groups. The odds of a vascular complication were not different in the two groups (OR = 1.26; 95% CI: 0.73-2.17; p = 0.41). In an adjusted Bayesian analysis, mortality (OR = 3.69; 95% CI: 0.30-38.51), MACE (OR = 1.68; 95% CI: 0.55-5.49), MI (OR = 1.42; 95% CI: 0.50-4.29) and dissections/perforations (OR = 0.38; 95% CI: 0.10-1.38) were not different in RA and OA groups. CONCLUSION: Our study is the first published Bayesian meta-analysis comparing MACE and peri-procedural outcomes in RA compared to OA. These findings lay the foundation for a randomized comparison between the two competing technologies.


Asunto(s)
Aterectomía Coronaria , Enfermedad de la Arteria Coronaria/terapia , Intervención Coronaria Percutánea , Calcificación Vascular/terapia , Aterectomía Coronaria/efectos adversos , Aterectomía Coronaria/mortalidad , Teorema de Bayes , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/fisiopatología , Humanos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/mortalidad , Calcificación Vascular/fisiopatología
4.
Cardiovasc Revasc Med ; 21(4): 467-472, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31501020

RESUMEN

BACKGROUND: Transcatheter left atrial appendage occlusion (LAAO) has become a suitable alternative to anticoagulation in patients with atrial fibrillation (AF). However, volume-outcome relationships at the individual operator level have not been studied. METHODS: Study population included 425 consecutive patients with AF undergoing LAAO from August 2015 to November 2018 by seven operators at BUMC-Phoenix. Operator volume was divided in tertiles by those with <40 cases/year (2 operators), 41-80 cases/year (3 operators) and >80 cases/year (2 operators). Patient data including comorbidities, labs, medications, procedural characteristics and outcomes were collected. The primary composite outcome was major adverse cardiac events (MACE) including mortality, stroke, bleeding and vascular complications. RESULTS: Mean age was 75 ±â€¯8 years and 251 (59%) were males. Mean CHA2DS2-VASc score was 4.5 ±â€¯1.3 points and mean HASBLED score was 3.9 ±â€¯1.0 points. MACE outcome was similar in the three operator groups in both unadjusted (p = 0.83) and adjusted (OR = 0.59: 95% Confidence Interval [CI]: 0.15-2.29, p = 0.45) analysis. The occurrence MACE was also similar between Interventional Cardiologist (IC) and Electrophysiologist (EP) operators in an unadjusted (p = 0.24) and adjusted (OR = 0.60: 95% CI: 0.21-1.68, p = 0.33) analysis. The secondary outcome of technical success did not differ among the three tertiles (p = 0.37) and among IC & EP operators respectively (p = 0.24) as well. CONCLUSION: Operator experience does not affect MACE and technical success even after adjusting for comorbidities. These results suggest a lower learning curve for LAAO with high technical success achievable even by low volume operators.


Asunto(s)
Apéndice Atrial/fisiopatología , Fibrilación Atrial/terapia , Función del Atrio Izquierdo , Cateterismo Cardíaco/instrumentación , Frecuencia Cardíaca , Accidente Cerebrovascular/prevención & control , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/mortalidad , Fibrilación Atrial/fisiopatología , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/mortalidad , Competencia Clínica , Femenino , Humanos , Curva de Aprendizaje , Masculino , Diseño de Prótesis , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Resultado del Tratamiento
5.
J Geriatr Cardiol ; 16(9): 706-709, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31645857

RESUMEN

BACKGROUND: Studies evaluating safety of warfarin and direct oral anticoagulants (DOACs) for prevention of stroke in patients with atrial fibrillation (AF) are lacking. METHODS & RESULTS: All patients (n = 196,521) receiving care at veteran's affairs with active cancer and AF from 2010-2015 were included. One-year mortality was significantly higher in unadjusted analysis with warfarin (44.9%) compared to dabigatran (25%, P < 0.001), rivaroxaban (24.4%, P < 0.001) and apixaban (30%, P < 0.001) and after adjusting for age, sex and type of cancer mortality (OR = 2.66, 95% CI: 2.52-2.82, P < 0.001). Risk of ischemic stroke (13.5% vs. 11.1%, 12.0%, 14.0%) was similar, however risk of hemorrhagic stroke was significantly higher among patients receiving warfarin (1.2%) compared to patients receiving dabigatran (0.5%), rivaroxaban (0.7%) and apixaban (0.8%) respectively, P = 0.04. CONCLUSIONS: We demonstrated the superior safety profile of DOACs compared to warfarin among patients with underlying cancer and AF. Warfarin was associated with higher mortality, similar ischemic stroke risk but higher risk of hemorrhagic stroke.

6.
Indian Heart J ; 71(6): 481-487, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32248922

RESUMEN

BACKGROUND: Frontal QRS-T angle (FQRST) has previously been correlated with mortality in patients with stable coronary artery disease, but its role as survival predictor after ST-elevation myocardial infarction (STEMI) remains unknown. METHODS: We evaluated 267 consecutive patients with STEMI undergoing reperfusion or coronary artery bypass grafting. Data assessed included demographics, clinical presentation, electrocardiograms, medical therapy, and one-year mortality. RESULTS: Of 267 patients, 187 (70%) were males and most (49.4%) patients were Caucasian. All-cause mortality was significantly higher among patients with the highest (101-180°) FQRST [28% vs. 15%, p = 0.02]. Patients with FQRST 1-50° had higher survival (85.6%) compared with FQRST = 51-100° (72.3%) and FQRST = 101-180° (67.9%), [log rank, p = 0.01]. Adjusting for significant variables identified during univariate analysis, FQRST (OR = 2.04 [95% CI: 1.31-13.50]) remained an independent predictor of one-year mortality. FQRST-based risk score (1-50° = 0 points, 51-100° = 2 points, 101-180° = 5 points) had excellent discriminatory ability for one-year mortality when combined with Mayo Clinic Risk Score (C statistic = 0.875 [95%CI: 0.813-0.937]. A high (>4 points) FQRST risk score was associated with greater mortality (32% vs. 19%, p = 0.02) and longer length of stay (6 vs. 2 days, p < 0.001). CONCLUSION: FQRST represents a novel independent predictor of one-year mortality in patients with STEMI undergoing reperfusion. A high FQRST-based risk score was associated with greater mortality and longer length of stay and, after combining with Mayo Clinic Risk Score, improved discriminatory ability for one-year mortality.


Asunto(s)
Electrocardiografía , Medición de Riesgo , Infarto del Miocardio con Elevación del ST/mortalidad , Infarto del Miocardio con Elevación del ST/terapia , Anciano , Puente de Arteria Coronaria , Femenino , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea , Pronóstico , Estudios Retrospectivos
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