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1.
Ecol Lett ; 27(5): e14415, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38712683

RESUMO

The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.


Assuntos
Folhas de Planta , Ciclo do Carbono , Carbono/metabolismo
2.
J Ethnobiol Ethnomed ; 20(1): 34, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486266

RESUMO

BACKGROUND: Traditional knowledge (TK) in Ladakh encapsulates a repository of experimental wisdom cultivated over millennia. Despite this cultural wealth, dwindling interest among the younger generations in the region's age-old practices underscores the urgency to document TK. The current study investigates the diverse usage of plants in Surru, Wakha and Lower Indus valleys of Western Ladakh exploring the influence of socioeconomic and ecological factors. METHODS: A stratified random sample approach was adopted to select 540 respondents for gathering information of useful plants through interviews and questionnaires. Participant observation, questionnaires, open-ended and semi-structured interviews were conducted for data collection. Free listing was done to create an extensive list of plants and their uses. Ethnobotanical metrics such as relative frequency of citation (RFC), relative importance index (RI), cultural value (CV) index and cultural importance (CI) index were computed to assess species applicability. Additionally, one-way analysis of variance (ANOVA) was utilized to discern significant differences in knowledge levels based on valleys, gender, education and religion using TK as a response variable. RESULTS: Altogether, we recorded 246 plant species under various ethnobotanical uses from Western Ladakh. These include medicinal (126), fodder (124), wild ornamentals (86), food (81), fuel wood (54), dye (20), religious (31) and others (34). Novel plant reports include Berberis brandisiana Ahrendt and Dactylorhiza kafiriana Renz. The dominant plant family is Asteraceae with 35 species. Suru valley exhibits the highest number of cited plants followed by Wakha-chu and Lower Indus valleys (192, 168 and 152 species, respectively). CONCLUSION: Disparities in plant use understanding are evident among different groups, prompting further investigation through intercultural comparisons. Plants such as Arnebia euchroma, Juniperus semiglobosa, and Artemisia species emerge with cultural importance. Gender, valley affiliation, religious background and the remoteness of a village all influence local plant knowledge. These variations are linked to socioeconomic disparities among communities.


Assuntos
Plantas Medicinais , Humanos , Etnobotânica , Inquéritos e Questionários , Meio Ambiente , Ração Animal
3.
Radiol Case Rep ; 19(5): 1990-1993, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38440743

RESUMO

Intussusception is one of the common conditions in children presenting with abdominal pain. The exact etiology of intussusception is unknown. Lead point is not identified in the majority of cases in children. Commonly, radiographic evidence suggests the presence of a target sign is diagnosis of intussusception. However, the presence of a double target sign in the case of intussusception is rare and depicts the presence of double intussusception. We present a case report of a 1-year-old child who presented to the emergency department with excessive crying for more than 10 hours. After the initial clinical assessment and acute management, an abdominal ultrasound revealed a double target sign on the sub-hepatic and left para-umbilical region which suggested double intussusception. No lead point was identified in our case. Early diagnosis and prompt treatment are the mainstay of management in such cases.

4.
Dalton Trans ; 52(43): 15986-15994, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37847415

RESUMO

Copper(II) complexes with tridentate NNN-ligands were utilized for Chan-Evans-Lam (CEL) cross-coupling reactions to enable the N-arylation of multifarious N-nucleophiles through the activation of aryl boronic acids. A condition-specific methodology was developed to chemoselectively target the amine versus sulfonamide N-arylation of 4-aminobenzenesulfonamide using new catalysts. Two different pyridine-based ligands and corresponding copper(II) complexes were characterized using 1H and 13C-NMR, FTIR, and UV-vis spectroscopy, HRMS, single-crystal X-ray diffraction, and cyclic voltammetry. Solvent and base-controlled cross-coupling reactions were observed, which led to the optimization of selective conditions for targeted C-N bond formation of sulfanilamides. Beyond the chemoselective processes reported here, a breadth of N-nucleophiles including sulfanilamides and arylamines were screened for arylation by this CEL catalyst.

5.
Tetrahedron Lett ; 1222023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37694227

RESUMO

We present a sodium trifluoroacetate (CF3CO2Na) mediated copper-catalyzed aza-Michael addition of aromatic amines with activated olefins under mild, aqueous reaction conditions. This simplistic protocol employs a copper catalyst (10 mol%) and water as solvent. This transformation occurs precisely with aromatic substituted amines containing both electron-donating (EDG) and electron-withdrawing (EWG) groups. A broad range of substrates were tested under the optimized conditions, which are producing good to moderate yields.

6.
Mol Biol Rep ; 49(11): 11177-11186, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36097126

RESUMO

BACKGROUND: Populations exhibit signatures of local adaptive traits due to spatial and environmental heterogeneity resulting in microevolution. The blue sheep is widely distributed across the high Asian mountains and are the snow leopard's principal prey species. These mountains differ in their evolutionary history due to differential glaciation and deglaciation periods, orography, and rainfall patterns, and such factors causes diversification in species. METHODS AND RESULTS: Therefore, we assess the phylogeographic status of blue sheep using the mitochondrial cytochrome b gene (220 bp) across the Indian Himalayan region (IHR) and its relationship with other populations. Of the observed five haplotypes, two and three were from the western Himalayas (WH) and eastern Himalayas (EH) respectively. One of the haplotypes from WH was shared with the population of Pamir plateau, suggesting historical maternal connectivity between these areas. The phylogenetic analyses split the blue sheep into two paraphyletic clades, and western and eastern populations of IHR were within the Pamir and Tibetan plateau clades, respectively. We observed a relatively higher mean sequence divergence in the EH population than in the WH. CONCLUSION: We propose five 'Evolutionary Significant Units' across the blue sheep distribution range based on observed variation in the species' ecological requirements, orography, climatic conditions, and maternal lineages, viz.; Western Himalaya-Pamir plateau (WHPP); Eastern Himalaya-Tibetan plateau (EHTP); Qilian mountains; Helan mountains and Hengduan mountains population. Despite the small sample size, population divergence was observed across the IHR, therefore, we suggest a transboundary, collaborative study on comparative morphology, anatomy, ecology, behaviour, and population genetics using harmonized different genetic markers for identifying the overall taxonomic status of the blue sheep across its range for planning effective conservation strategies.


Assuntos
Citocromos b , Genética Populacional , Mitocôndrias , Animais , Citocromos b/genética , Haplótipos/genética , Filogenia , Filogeografia , Ovinos/genética , Mitocôndrias/metabolismo
7.
Ecol Evol ; 12(7): e9120, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35866011

RESUMO

Brown bear-mediated conflicts have caused immense economic loss to the local people living across the distribution range. In India, limited knowledge is available on the Himalayan brown bear (HBB), making human-brown bear conflict (HBC) mitigation more challenging. In this study, we studied HBC in the Lahaul valley using a semi-structured questionnaire survey by interviewing 398 respondents from 37 villages. About 64.8% of respondents reported conflict in two major groups-crop damage (30.6%) and livestock depredations (6.2%), while 28% reported both. Conflict incidences were relatively high in summer and frequently occurred in areas closer to the forest (<500 m) and between the elevations range of 2700 m to 3000 m above sea level (asl). The dependency of locals on forest resources (70%) for their livelihood makes them vulnerable to HBC. The "upper lower" class respondents were most impacted among the various socioeconomic classes. Two of the four clusters were identified as HBC hot spots in Lahaul valley using SaTscan analysis. We also obtained high HBC in cluster II with a 14.35 km radius. We found that anthropogenic food provisioning for HBB, livestock grazing in bear habitats, and poor knowledge of animal behavior among the communities were the major causes of HBC. We suggest horticulture crop waste management, controlled and supervised grazing, ecotourism, the constitution of community watch groups, and others to mitigate HBC. We also recommend notifying a few HBB abundant sites in the valley as protected areas for the long-term viability of the HBB in the landscape.

8.
Chemistry (Basel) ; 4(2): 560-575, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38031556

RESUMO

Arylboronic acids are commonly used in modern organic chemistry to form new C-C and C-heteroatom bonds. These activated organic synthons show reactivity with heteroatoms in a range of substrates under ambient oxidative conditions. This broad reactivity has limited their use in protic, renewable solvents like water, ethanol, and methanol. Here, we report our efforts to study and optimize the activation of arylboronic acids by a copper(II) N-heterocyclic carbene (NHC) complex in aqueous solution and in a range of alcohols to generate phenol and aryl ethers, respectively. The optimized reactivity showcases the ability to make targeted C-O bonds, but also identifies conditions where water and alcohol activation could be limiting for C-C and C-heteroatom bond-forming reactions. This copper(II) complex shows strong reactivity toward arylboronic acid activation in aqueous medium at ambient temperature. The relationship between product formation and temperature and catalyst loading are described. Additionally, the effects of buffer, pH, base, and co-solvent are explored with respect to phenol and ether generation reactions. Characterization of the new copper(II) NCN-pincer complex by X-ray crystallography, HR-MS, cyclic voltammetry, FT-IR and UV-Vis spectral studies is reported.

9.
PLoS One ; 16(5): e0239690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33974622

RESUMO

The Himalayan region is one of the global biodiversity hotspots. However, its biodiversity and ecosystems are threatened due to abiotic and biotic drivers. One of the major biotic threats to biodiversity in this region is the rapid spread of Invasive Alien Species (IAS). Natural forests and grasslands are increasingly getting infested by IAS affecting regeneration of native species and decline in availability of bio-resources. Assessing the current status of IAS and prediction of their future spread would be vital for evolving specific species management interventions. Keeping this in view, we conducted an in-depth study on two IASs, viz., Ageratina adenophora and Lantana camara in the Indian part of Kailash Sacred Landscape (KSL), Western Himalaya. Intensive field surveys were conducted to collect the presence of A. adenophora (n = 567) and L. camara (n = 120) along an altitudinal gradient between 300 and 3000 m a.s.l. We performed Principal Component Analysis to nullify the multi-colinearity effects of the environmental predictors following MaxEnt species distribution model in the current and future climatic scenarios for both the species. All current and future model precision (i.e., Area Under the Curve; AUC) for both species was higher than 0.81. It is predicted that under the current rate of climate change and higher emission (i.e., RCP 8.5 pathway), A. adenophora will spread 45.3% more than its current distribution and is likely to reach up to 3029 m a.s.l., whereas, L. camara will spread 29.8% more than its current distribution range and likely to reach up to 3018 m a.s.l. Our results will help in future conservation planning and participatory management of forests and grasslands in the Kailash Sacred Landscape-India.


Assuntos
Ageratina/fisiologia , Conservação dos Recursos Naturais , Ecossistema , Lantana/fisiologia , Biodiversidade , Mudança Climática , Humanos , Índia , Espécies Introduzidas , Modelos Biológicos
10.
Biodivers Data J ; 7: e31588, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148933

RESUMO

Natural riverine areas mark ecotonal habitats harbouring a characteristically diverse faunal assemblage, especially birds that also use these habitats as pathways crucial for their movement. Increasingly, riverine systems are subjected to large-scale habitat alterations due to climatic fluctuations and anthropogenic changes. Therefore, it is important to understand broad-scale community patterns for conservation planning and prioritisation for these ecotone habitats. The Bhagirathi river is one of the major headwaters of the river Ganges; despite its rich and diverse fauna, little is known about the bird species that inhabit this montane region. This study presents an extensive list of 281 bird species from 59 families, their seasonal distribution and habitat associations as recorded from field surveys along the riverine areas between April 2013 and May 2018. The present communication simultaneously discusses a few noteworthy sightings for the region and provides a baseline for future research on the distribution of birds in the Western Himalaya.

11.
Zoology (Jena) ; 116(5): 300-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23932023

RESUMO

Forage selection decisions of herbivores are often complex and dynamic; they are modulated by multiple cues, such as quality, accessibility and abundance of forage plants. To advance the understanding of plant-herbivore interactions, we explored foraging behavior of the alpine lagomorph Royle's pika (Ochotona roylei) in Kedarnath Wildlife Sanctuary, India. Pika bite counts on food plants were recorded through focal sampling in three permanently marked plots. Food plant abundance was recorded by traditional quadrat procedures; forage selection was estimated with Jacob's selection index. Multiple food-choice experiments were conducted to determine whether forage selection criteria would change with variation in food plant composition. We also analyzed leaf morphology and nutrient content in both major food plants and abundantly available non-food plants. Linear regression models were used to test competing hypotheses in order to identify factors governing forage selection. Royle's pika fed primarily on 17 plant species and each forage selection decision was positively modulated by leaf area and negatively modulated by contents of avoided substances (neutral detergent fiber, acid detergent fiber, acid detergent lignin and tannin) in food plants. Furthermore, significance of the interaction term "leaf size × avoided substance" indicates that plants with large leaves were selected only when they had low avoided substance content. The forage selection criteria did not differ between field and laboratory experiments. The parameter estimates of best fit models indicate that the influence of leaf size or amount of avoided substance on pika forage selection was modulated by the magnitude of predation risk.


Assuntos
Preferências Alimentares , Herbivoria , Lagomorpha , Animais , Índia , Modelos Estatísticos
12.
J Ethnopharmacol ; 143(2): 621-30, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22884871

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Sowa-rigpa system of traditional healing has been practiced from time immemorial in western Ladakh but its existence is in jeopardy today. Documentation of information on various aspects of this system such as treatment methods, materials used for medicine and socio-cultural aspects is needed to ensure the long-term survival of this system. MATERIALS AND METHODS: Extensive field surveys were conducted from March 2009 to June 2011 in three different Valleys of the Kargil district. Interviews with traditional healers, village heads and local people were conducted using semi-structured questionnaires and participatory observations to assess the current status of traditional medicine system. Plant specimens were collected from the field for identification and herbarium preparation which were later deposited in herbaria for future reference. RESULTS: 160 plants were recorded to be used by traditional healers of Western Ladakh. Traditional healing system (THS) is taking care of 30% of public healthcare. Only 36 traditional healers are left in this region of which 67% was found along the Wakha-chu Valley, followed by the Lower Indus Valley (17%) and the SuruValley (16%). The transfer of knowledge to the next generation is very low (25%) in Kargil. Low income and continuously deteriorating social status of healers has contributed to the decline of this system. CONCLUSIONS: Lack of interest in young generation in adopting this system may pose a threat to the survival of Sowa-rigpa. Integration of this system with the modern healthcare system and more government support may prove effective to enhance its deteriorating conditions.


Assuntos
Atenção à Saúde/tendências , Medicina Tradicional/tendências , Fitoterapia/tendências , Adulto , Idoso , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Plantas Medicinais , Inquéritos e Questionários , Adulto Jovem
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