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Twelve lacustrine sediment samples from a relict lake in the Kalla Glacier valley were co-dated using AMS radiocarbon (14C) and infrared stimulated luminescence (IRSL) dating methods. In general, the radiocarbon ages of bulk organic matter were older by a minimum of 1500 years compared to (age depth) modeled luminescence ages after fading corrections. This is observed for the first time in the lake sediments of High Himalayan Crystalline zone. A combination of lipid n -alkane data, Raman spectra and geochemical proxies suggested that this was due to ancient organic carbon (OCancient) that is a mixture of pre-aged (OCpre-aged) and petrogenic (OCpetro) organic carbon within older glacial moraine debris that served as sediment source to the lake. Raman spectra suggest the presence of moderate to highly graphitized OCpetro in all the profile samples. The OCpetro contributed 0.064 ± 0.032% to the sediment and the lake stored 2.5 ± 0.7 Gg OCpetro at variable rates during the last 16 kyr, with the mean burial flux 160 kg OCpetro yr−1. This study implies (1) employing another independent dating method in addition to radiocarbon method using bulk sediment organic matter, if the carbon content is low, to observe any discrepancy, and (2) a need to investigate on the fate of OCpetro as many such small lakes become relict in this region. [ABSTRACT FROM AUTHOR]

Monsoon precipitation plays a crucial role in shaping the diversity of vegetation in the Himalayas, both in terms of temporal and spatial distribution. While palynology has traditionally been employed to reconstruct the past climate of the Himalaya, there has been limited understanding of how monsoon-related changes affect the structure and distribution of vegetation. To address this, we analysed pollen data from a 3 m deep sedimentary profile in the higher Sikkim Himalaya to reconstruct monsoon driven changes in vegetation diversity. Our results show a highly fluctuating trend of pollen and diversity parameters at late-Pleistocene-Holocene transition for which fluctuating hydroclimatic conditions and differential pollen preservation in coarser sediments is attributed. During the Early Holocene (10,438–7934 cal yrs BP) favourable hydroclimatic conditions led to a rapid expansion of mixed broad-leaved forests, marked by higher values of richness and alpha diversity. Between 7934 and 5481 cal yrs BP, the region experienced moderate hydroclimatic conditions that facilitated expansion and diversification of woody taxa, and correlated with the global Holocene Climate Optimum (HCO). Conversely, from 5481 to3949 cal yrs BP, declining total pollen count (TPC), species richness, and alpha diversity indicates significant shifts in vegetation composition under deteriorating climatic conditions, which corresponds with the 4.2 ka event worldwide. From 3949 to 2049 cal yrs BP, an increasing yet variable trend in TPC and diversity indices, suggests warm-humid conditions prevailed in the region. During the last 1086 cal yrs, an increasing trend is recorded in the palyno assemblage and diversity parameters suggesting ameliorating climate, matches well with the Mediaeval Climate Anomaly (MCA). Our inferences suggest that the palyno assemblage and diversity parameters are quiet sensitive to warm and humid conditions. [ABSTRACT FROM AUTHOR]

Thermokarst (Thaw) lakes are landforms found in topographic depressions created by thawing ground ice in permafrost zones. They play an important role in the regulation of climatic functions. These lakes are a manifestation of warming surface temperatures that accelerates the ice-rich permafrost to degrade by creating marshy hollows/ponds. In the current global warming scenario, the thermokarst lakes in the high mountain regions (Himalaya) are expected to grow further. This accelerate permafrost thawing which will affect the carbon cycle, hydrology and local ecosystems. This phenomenon has attracted huge scientific attention because it has led to a rapid mass change of glaciers in the region, including extensive changes occurring on peri-glacial environments. The most striking fact is the release of an enormous amount of greenhouse gases, including methane, carbon dioxide and nitrous oxide that is locked in these lakes. The present study delves into the thermokarst lakes in the upper reaches of Chandra Valley and Western Himalaya. The study also aims at designating the impact of their changes on the ecosystem, particularly their influence on the atmospheric greenhouse gas concentrations. [ABSTRACT FROM AUTHOR]

The present study investigates latero-frontal moraines to reconstruct the pattern of glacier advances and associated climate variability in the Suru valley, southwestern Zanskar Himalaya. Impressive sets of latero-frontal moraines and discontinuous morainic ridges (recessional) represent the records of the past glacier advance and retreat. The northerly trending latero-frontal moraines that descend down the tributary valleys and terminate at the trunk Suru valley are the geomorphic expression of one of the oldest preserved record of glacier advance and is named as Tongul glacial stage. Previous studies (based on 10Be and 14C ages) defining the chronology of Tongul glacial stage are either limited in number (14C ages) or have a large spread (10Be ages) and hence demand further investigation. Optically stimulated luminescence (OSL) dating suggests that the Tongul glacial stage responded to the global last glacial maximum (gLGM) dated between ~20 and 24 ka. We suggest that the Tongul glacial stage was driven by enhanced mid-latitude westerlies and reduced temperature (viz., continental cooling) during MIS 2 and facilitated by corresponding long winters. [ABSTRACT FROM AUTHOR]

Mycetoma is a chronic, slowly progressing granulomatous subcutaneous infection caused by true fungi (eumycetoma) or filamentous bacteria (actinomycetoma). The present case report is a rare case of Actinomycotic Mycetoma involving wrist due to Streptomyces species. A 53-year-old male presented with multiple swellings over the right wrist and forearm with sinuses discharging sero-purulent pus since 3 years. Patient underwent incision and drainage and appropriate antibiotic course after the complete diagnosis. This case report emphasises the role of meticulous clinical examination assisted by microbiological cultures and histopathological studies which are mandatory in the diagnosis, management and assessment of the prognosis of such unusual cases. [ABSTRACT FROM AUTHOR]

The present communication deals with pollen analyses of moss polsters in order to understand the pollen rain from Udhampur District of Jammu and Kashmir, India. The study revealed that the pollen ofPinussp. (average 46% pollen) dominates the pollen rain, which could be attributed to its high pollen productivity and excellent pollen dispersal efficiency, followed byCedrussp., andPodocarpussp. However, other conifers such asAbiessp.,Piceasp.,Juniperussp. andTsugasp., as well as the broad-leaved taxa suchAlnussp.,Betulasp.,Ulmussp.,Quercussp.,Carpinussp.,Corylussp.,Juglanssp.,Ilexsp.,Mallotussp.,Elaeocarpussp. andAesculussp., were sporadically recorded which could be due to either their poor pollen dispersal efficiency or poor preservation in the substrate. Tubuliflorae, Poaceae, Amaranthaceae, Malvaceae and Cerealia are the other prominent taxa of the pollen rain, revealing their actual composition in the ground vegetation. [ABSTRACT FROM PUBLISHER]

Permafrost is an integral, but hardly ever studied, component of cryosphere in the Indian Himalayan. Despite the fact that a considerable area of the Indian Himalaya is underlain by frozen ground (permafrost) which is highly sensitive to climate change, scientific data on its degradation and environmental effects are lacking. Meteorological air temperature data has shown an increase in the global average temperatures and more importantly the rise of temperature in the Himalaya has been reported to be double than the global averages. This has resulted in the permafrost thawing and increase in the instability of the rock slopes in steep areas. Therefore, it is indispensable to study and generate scientific data on permafrost, covering wider geographical and ecological domains of the Indian Himalaya and use multiple parameters that directly or indirectly influence the permafrost. [ABSTRACT FROM AUTHOR]

We present pollen proxy records of the variability in the Indian Summer Monsoon (ISM) precipitation during the last ∼4ka (ka= thousand years ago; Late Holocene) from a lacustrine area of Koriya District in Chhattisgarh (C'garh), (central Indian core monsoon zone [CMZ]), India. The results show that open, mixed tropical, deciduous forest occupied the region under a warm and moderately humid climate probably indicative of moderate monsoon precipitation between ∼3796 and ∼2428 cal yr BP. Subsequently, between ∼2428 and ∼1431 cal yr BP, the forest became dense and succeeded the open, mixed tropical, deciduous forest owing to the prevalence of a warm and relatively more humid climate with increased monsoon precipitation. The forest became less diversified from ∼1431cal yr BP to Present under the regime of a warm and relatively less humid climate with decreased monsoon precipitation. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new classTs;ak[A, B, α, β] of analytic functions by using a newly defined convolution operator. This class contains many known classes of analytic and univalent functions as special cases. We derived some interesting results including inclusion relationships, a radius problem and sharp coefficient bound for this class. [ABSTRACT FROM AUTHOR]