Northeast India Research Articles

Ensemble versus deterministic lightning forecast performance at a convective scale over Indian region

The present study quantifies the improvement achieved in lightning forecast skill of the NCMRWF regional ensemble prediction system (NEPS-R) compared to its deterministic counterpart (CNTL). The lightning forecasts over study regions of East and Northeast India (ENEI) and Peninsular India (PI) during the pre-monsoon season and Central-East and Northeast India (CENEI) during the monsoon season have been verified using lightning observations from the Indian Institute of Tropical Meteorology (IITM) Lightning Detection Network (LDN). The persisting systematic negative bias in deterministic and EPS-based forecasts of the ensemble mean (EnsMean) and ensemble maximum (EnsMax) indicate the lack of spread among the members, supported by the low values of ensemble spread over all the study regions. EnsMean has the lowest RMSE, with a decrease in error ranging from 0.8 % to 2.18 % compared to CNTL. Categorical skill scores indicate that the EPS-based forecasts (EnsMean and EnsMax) are more skillful than the deterministic forecast at all thresholds and lead times. Further, Fractions Skill Score (FSS) establishes the superiority of the ensemble forecasts over the deterministic forecasts, where for threshold >1, EnsMean is skillful at comparatively smaller neighborhood sizes (ENEI and PI ~68 km; CENEI ~36 km for day-1) than CNTL (ENEI-116 km; PI-196 km; CENEI-68 km). EnsMax at higher thresholds (>5 and > 10) is skillful at lesser neighborhood sizes ranging from 116 to 276 km compared to CNTL (>401 km) for day-1. Hence, skillful re-scaled EPS forecasts based on FSS could provide better guidance for the forecasters. The Continuous Ranked Probability Score of EPS forecasts is lower by around 9 % than the Mean Absolute Error of CNTL forecasts, and the ROC of EPS shows better discrimination of events and non-events compared to CNTL. These highlight the merits of using an EPS over a deterministic system for forecasting a field of high spatial variability, like lightning, and thereby, the use of vast computational resources to run a convective scale EPS is justified.

Canine parvovirus in North-East India: a phylogenetic and evolutionary analysis.

Canine parvovirus type 2 (CPV-2) infection in dogs is considered as one of the most common cause of morbidity and mortality in young dogs and continues to occur with high incidence worldwide. Despite a single-stranded DNA virus, CPV-2 possesses a high mutation rate which has led to the development of new variants from time to time. These variants are classically classified based on the amino acid markers present in the VP2 gene. In this study, we examined 20 different cases of CPV-2 infection from seven different states of the North East region (NER) of India. The near-complete genome sequences of all these isolates were subjected to phylodynamic and phylogeographic analysis to evaluate the genetic diversity and geographical spread of CPV-2 variants. Analysis of the deduced amino acid sequences revealed residues characteristic of the 'Asian CPV-2c lineage' in all the 20 sequences confirming it as the dominant strain circulating in NER, India. The phylogenetic analysis based on the whole genome showed that all 20 sequences formed a monophyletic clade together with other Asian CPV-2c sequences. Furthermore, phylogeographic analysis based on the VP2 gene showed the likely introduction of Asian CPV-2c strain to India from China. This study marks the first comprehensive report elucidating the molecular epidemiology of CPV-2 in India.

Impact of boundary layer parameterizations on simulated seasonal meteorology over North-East India

This study evaluated the accuracy of six planetary boundary layer (PBL) parameterization schemes in simulating two different seasons of pre-monsoon and monsoon in India's North-East region through the Weather Research and Forecasting (WRF) model. Twelve one-month simulations were conducted with the PBL schemes, six each for April (pre-monsoon) and July (monsoon), and the model outputs were compared against observations. Three non-local schemes, Asymmetric Convective Model (ACM2), Yonsei University (YSU), Shin-Hong (HONG), and three local schemes, Quasi Normal Scale Elimination (QNSE), Mellor Yamada Janjic (MYJ) and Mellor Yamada Nakanishi Nino (MYNN3), were tested. The meteorological variables of temperature, relative humidity (RH), wind speed, wind direction, and rainfall were evaluated, and the performance of each scheme for each meteorological variable is reported. The 2m temperature (T2) variable was well simulated by ACM2, MYJ in April, and YSU in July, while MYNN3 best simulated the 2m RH (RH2) during both seasons. 10m wind speed (WS10) and directions (WD10) were better simulated by MYNN3, HONG and YSU. HONG also best-simulated rainfall in April and MYJ in July. April and July being rainfall periods, an analysis of the schemes’ simulated rainfall frequency was also carried out. Moreover, the PBL schemes were also ranked, considering their combined performance with all the above meteorological parameters. While considering both the seasons and all meteorological variables, the scale-aware scheme, HONG, was the best scheme and can be used to simulate both seasons. Additionally, an in-depth analysis of surface and atmospheric parameters was also carried out to reason the simulated meteorology. QNSE expends the highest amount of its surface energy through surface evaporation, leading to the lowest surface skin temperature and T2 predictions. In contrast, MYNN3 produced the lowest mixing, which caused the moistest boundary layer, highest RH, cloud cover, and highly overestimated rainfall. Besides evaluation, which will help to choose a suitable PBL scheme for weather predictions in this region, this study also identifies the characteristics and deficiencies of PBL and surface layer schemes for improvement.

Garra ngopi sp. n., a new fish species (Cyprinidae: Labeoninae) from the Brahmaputra River basin, Arunachal Pradesh, North–Eastern India

Garra ngopi sp. n., a new fish species (Cyprinidae: Labeoninae) from the Brahmaputra River basin, Arunachal Pradesh, North–Eastern India

Evaluation of the minor clinical features of Hanifin and Rajka amongst children with atopic dermatitis, visiting a tertiary care hospital in North Eastern India

Atopic Dermatitis (AD) is a commonly encountered, extremely itchy, chronic and relapsing skin disorder, which is characterized by inflammation in the skin. It typically has its onset in childhood, presenting with eczematous lesions; and can also be associated with personal or family history of “atopy”, usually most often. The criterion put by Hanifin and Rajka, encompassing 4 major plus 23 minor criteria, is not infrequently used as a diagnostic criterion for this disease in a hospital setup; however, the frequency of occurrence of the minor criteria usually varies in the population.The study aims at estimating the frequency of the minor diagnostic criteria of the Hanifin and Rajka in children with AD. This was a hospital-based cross-sectional study, that was conducted on 70 children (less than 18yrs of age) by taking their history, doing clinical and ophthalmological examination and some basic tests.The most common occurrence amongst the minor criteria estimated from our study was xerosis i.e., in 45(64.2%). The other common minor criteria observed were pityriasis alba (42.8%) facial erythema (40%), orbital darkening (37.14%) Early age of onset was seen in children (35.7%). There is variation in the clinical features of AD according to geography and population. The prevalence and severity of the disease are dependent on several factors like ethnicity/race and environment. Hence, it is important for dermatologists to know the usual and common ways the disease presents, in a given population for the diagnosis so as to diagnose and treat the patients at an earlier stage and before significant discomfort.

Topiramate’s role in Yaba pill abuse: A first report and a short review from Northeast India

Topiramate’s role in Yaba pill abuse: A first report and a short review from Northeast India

Phytochemical screening, nutritional, antinutritional, antioxidant, GCMS and mineral analysis of Zanthoxylum rhetsa (Roxb.) DC: Insights from tribal consumption in Mizoram, Northeast India

The plant Zanthoxylum rhetsa Roxb, a member of the Rutaceae family, holds dual significance in certain communities, particularly in Mizoram, Northeast India, where it is valued for its medicinal properties and consumed as a vegetable. This study comprehensively analyzes the phytochemical, nutritional, antinutritional, and antioxidant properties and the mineral content of Z. rhetsa, a plant traditionally consumed by tribal communities in this region. Minerals such as aluminum, copper, iron, manganese, nickel, and zinc were measured using Atomic Absorption Spectroscopy (AAS). Gas Chromatography-Mass Spectrometry (GC-MS) analysis was conducted to determine the chemical composition of the samples. Phytochemical screening revealed the existence of several bioactive components, such as tannins and flavonoids, while nutritional studies validated the plant's abundance of key nutrients. Among the minerals, manganese was found in the highest concentration (481.356 mg/100 g of DW), while nickel was present in the lowest concentration (1.614 mg/100 g of DW). The total calorific content was ascertained to be 51.344 Kcal/100g, adequate for dietary requirements. Additionally, the total phenolic content measured was 8.28 mg/g in gallic acid equivalent, and the total flavonoid content was 43.04 mg/g in quercetin equivalents. The existence of antinutritional compounds in differing amounts necessitates meticulous evaluation, particularly with the intake of fruits that may possess elevated levels of these substances. This comprehensive assessment highlights the nutritional significance of Z. rhetsa in local diets, emphasizing its dual role as a source of beneficial nutrients and potential antinutritional factors.

Contagious Bovine Pleuropneumonia: A Review

Contagious bovine pleuropneumonia (CBPP) is a bacterial disease, the causative agent of which is Mycoplasma mycoides subsp. Mycoides. The CBPP disease is one of important disease to be given attention because it is causing heavy mortality in bovines all over the world with African continent being hardly hit due to vagaries of bacteria. Air droplets is primary source of infection. Colonization in lower respiratory tract, Mmm invades arteries cause vasculitis. Many pathways of Mmm organism to cause destruction in host animal, presence of Gts ABC is one such mechanism. In CBPP we see pulmonary sequestra in chronic cases, severe fibrinous bronchopneumonia and pleural effusion during the acute to subacute phases. For confirmatory diagnosis, laboratory investigation and use of molecular techniques is recommended. Isolation of causative agent is also optimal method for diagnosis. The use of danofloxacin, tetracycline, flufenicol etc have been documented with varying degree of efficiency. Control over movement of bovine species, adequate space (where droplet spread is prevented) for each animal and vaccination are recommendatory steps. Though India has been declared CBPP free in 2007 we still need cautious approach and continue surveillance because north east of India seems very vulnerable to CBPP. Also, the fact that animal husbandry and agriculture drive economy of some of our most populous states it is all the more important that we give due consideration and focus on CBPP.

Two new Gastroptychia Kobelt & Möllendorff, 1900 from Darjeeling and West Khasi Hills, northeastern India (Gastropoda: Cyclophoroidea: Diplommatinidae)

Two new species, namely Gastroptychia geoffreyi sp. nov. and Gastroptychia collicola sp. nov., are described respectively from Darjeeling and West Khasi Hills, northeastern India based on historical collections at the Natural History Museum, London. Gastroptychia collicola sp. nov. is distinguished from sympatric species by the presence of a unique palatal swelling and a palatal lamella, while Gastroptychia geoffreyi sp. nov. is distinguished from sympatric species by its dense ribs. The type specimens of all sympatric sinistral species, namely Gastroptychia insignis (Godwin-Austen, 1870), Gastroptychia gibbosa (W. T. Blanford, 1868), Gastroptychia gibberosa (Godwin-Austen, 1892), and Gastroptychia jaintiaca (Godwin-Austen, 1870), are illustrated for comparison.

A Study on the Role of Women in Garo Tribal Society

Women are the main ornaments of a society. The place of men in society is the same place as that of a woman. In a society where there is equal rights between women and men, we can call it a healthy society. Women provide the fulfillment for the creation of a society. Therefore, the tribal people have always given high status to women. The Garos are one of the various tribes living in North East India where the role of women is advanced in all aspects. Therefore, the Garos are called the matriarchal tribe. The Garo women play a special role in managing everything from raising the family to managing everything. Our research will try to discuss the role of women in the life of the garo society.

Towards maximizing geospatial data usage in north eastern India using open-source scalable user-centric applications

Abstract. The north eastern region of India is characterized by limited physical connectivity and challenging terrain, that requires innovative approaches for effective developmental planning and monitoring using geospatial data and user-centric applications. This paper focuses on leveraging space-based data and applications to address these challenges and enhance decision-making processes in governance. A unified framework for interoperable spatial data sharing has been developed, ensuring that data is easily discoverable, searchable, and consumable through metadata standards and OGC interoperable data services. A dedicated spatial data repository has been established, offering real-time access to over 1400 geospatial datasets and facilitating better decision-making and geo-analytics among diverse user groups. The repository operates on an open-source platform with integrated map viewers and geo-analytics tools, allowing for interactive exploration and visualization of geospatial data. Additionally, 35 user-centric geospatial applications have been operationalized, all developed using open-source geospatial tools and standards. Capacity building programs have been conducted to increase awareness and maximize the utilization of geospatial data services and applications across the region. The platform has boosted utilization of geospatial data services and applications in the region for overall planning and developmental activities for smart governance and societal benefits.

Rosettes in a matrix: Predicting spatial variation in density of a large felid in a forest‐production mosaic

AbstractLarge carnivores are keystone for ecosystems and flagships for conservation efforts but face severe threats globally. Protected areas are vital for the conservation of these charismatic species along with a host of ecological processes. However, the extent and scope of protected areas for conservation of all threatened species is limited, especially in the global south. Considering larger landscapes that can be compatible with large carnivore conservation goals is an alternative approach to ensure their persistence. This study explores the potential of multi‐use landscapes for the persistence of a globally threatened large felid, the Indian leopard (Panthera pardus fusca). This study investigated the spatial variability of leopard densities across a land‐use gradient using spatially explicit capture‐recapture framework in a tea‐plantation‐dominated forest‐production landscape mosaic in the Duars region of northeastern India. While the density of leopards in this landscape was estimated to be 7.96 ± 1.56 (SE) per 100 km2, significant (p = .048, t = 2.02, df=61) differences in estimates were observed between tea‐plantations (11.53 ± 2.72 (SE) leopards per 100 km2) and the forested habitats (4.67 ± 2.07 (SE) per 100 km2). Densities between tea plantations and protected areas (a subset of the forested habitat) were found to be comparable (9.19 ± 4.55 (SE) per 100 km2). The study posits that conservation‐compatible land use in landscapes shared with people can host a higher density of adaptable large felids like leopard than forested areas and that conservation planning needs to move beyond the dominant PA‐centric paradigm. The study also reinforces the importance of multi‐use landscapes for wildlife conservation, especially for an adaptable large felid.

Evaluating Tobacco Cessation Readiness in OPMD Patients Using the Transtheoretical Model in a tertiary care setting in Northeast India

Background: Oropharyngeal cancers pose significant global health challenges and addressing public awareness, early symptoms, and risk factors, alongside promoting tobacco cessation among individuals with potentially malignant oral disorders, is crucial for reducing the disease burden.Objective: Evaluating the degree of public knowledge of oral malignancy & OPMD, initial signs & risk factors amongst patients going to a dental college in North East India, as well as readiness to quit tobacco amongst OPMD patient.Methods: This cross-sectional investigation was undertaken at the Department of Public Health Dentistry, Tertiary care Hospital in Guwahati. 200 participants aged 15-65 years who consented were surveyed using a self-administered questionnaire. Collected data underwent thorough checks for completeness and accuracy. To determine the odd's ratio (OR) and to summarise the data, descriptive & inferential statistics were used. To test the relationship, data were dichotomised. Oral lesions present or absent; behavioural phases were divided into two categories: (preparation + action) & (precontemplation + contemplation). P < 0.05 was used as the statistical significance threshold.Results: Most participants were in the contemplation stage regarding tobacco's risks, neglecting other risk factors like alcohol & inadequate dental hygiene for oral malignancy/OPMD development.Conclusions: The lack of knowledge of oral malignancy & potentially malignant disorders (OPMDs) amongst North Eastern Indian communities, underscores the immediate demand for targeted education and health promotion campaigns. Emphasizing early symptom recognition, risk factors, and prevention measures, tailored to diverse communication preferences, is crucial.

Decoding the Strands of Women Oppression in Fiction of North Eastern Women Writers: A Study of Temsula Ao’s The Night (2005), Easterine Kire’s A Terrible Matriarchy (2007) and Jahnavi Barua’s Rebirth (2010)

India had long come out of the shadows of otherisation by the West, but ironically, it had constructed its own facets of misinterpretation and otherisation of its diverse indigenous groups within the subcontinent. Northeast India is one such geographical region that have always been viewed as exotic, backward owing to the distinct cultural and traditional patterns of its numerous tribes, castes and groups, of which very little is explored by the mainstream society and hence deemed as rooted in backwardness. The region has always been entangled in the web of national, ethnic, regional identities as it seems to exist in isolation from mainland India and grapples with insurgency and the inability to accommodate long term cultural and indigenous diversity. Additionally, the cultural, ethnic ethos and norms of each indigenous group acts as an influential factor in shaping the identities of the North East Indian people. In such contexts, the women question becomes a case of double marginalisation owing to unbalanced power relations as well as patriarchal customs and rules of various indigenous groups and the perpetual militarisation and regional identity crisis in the area. The research aims to investigate the factors moulding the identity of north eastern woman from the lens of gendered subalternity, through some strong, vivid narratives with passive-strong female characters. It is an attempt to understand how the multiple social ideologies of region, ethnicity, race, gender, nation, identity overlap to delineate to hierarchal disparities in the society contributing to victimisation of women.

North-East India: A ‘Gateway’ to Enhanced Connectivity with East and Southeast Asia

North-East India, situated at the crossroads of South, East, and Southeast Asia, is poised to become a vital ‘gateway’ to foster seamless connectivity and cooperation between India and the ‘Asia-Pacific’ region. The region’s strategic location makes it a crucial player in India’s foreign policy, particularly through the ‘Act East Policy’ aimed at strengthening ties with ‘East’ and ‘Southeast Asia.’ With its geographical proximity to Southeast and East Asian markets, North-East India has immense potential for increased investment under the ‘Act East Policy,’ making it an attractive hub for trade, commerce, and connectivity. The region’s connectivity infrastructure, including roads, railways, airports, and ports, is being upgraded to facilitate seamless trade and people-to-people contacts. This improvement in connectivity is expected to boost regional economic growth, enhance India’s Act East Policy, and foster ASEAN-India cooperation. This paper explores North-East India’s potential as a ‘gateway’ to enhance connectivity with ‘East’ and ‘Southeast Asia,’ highlighting its geo-strategic significance, economic opportunities, and cultural connections, and assessing its role in shaping India’s foreign policy and regional integration. The paper also investigates the government’s initiatives and projects to facilitating connectivity with ‘East’ and ‘Southeast Asia.

Investigation of meteorological variables and associated extreme events over North-East India and its adjoining areas using high-resolution IMDAA reanalysis

Investigation of meteorological variables and associated extreme events over North-East India and its adjoining areas using high-resolution IMDAA reanalysis

Investigation of biomass gasification and fluidization behaviour for pilot double tapered bubbling fluidized bed reactor.

The present investigation discusses syngas production through gasification from six different bamboo biomass species available in India's northeast region (Mizoram). The thermochemical conversion of biomass to syngas is accomplished in a novel double-tapered reactor. The pre-processing stage of biomasses includes various shredding, drying, and sieving methods. In the processing stage, the biomass (20g) is fed to the reactor regularly. The heating element in the interior of the reactor supplies the heat required (600-1000°C) for the combustion and gasification of biomass samples. The influence of various particle sizes on bed voidage, pressure drop, bed height, suspension density, gas yield, heat transfer, and carbon conversion efficiency is studied. The tapered reactor enhanced the bed hydrodynamics. It is observed that the H2 and CO2 composition increases with the temperature (> 900°C), whereas the CO composition is reduced as a result of the shift reaction. However, the CH4 yield is enhanced at a temperature (< 800°C) but lessened at higher temperatures due to a reduction in moisture content. The carbon conversion efficiency (CCE) and the dry gas yield (YG) values obtained are better for the particle size of 1.18mm than the other particle sizes. The energy from biomass resources is promising regarding sustainability, availability, and efficacy. The current approach discusses the syngas generation from bamboo biomass through gasification under varied temperature ranges (600-1000°C), equivalence ratio (0.2), particle sizes (380µm, 600µm, and 1.18mm), superficial velocity (0-2m/s) in a pilot 5kg/h DTBFBR of height 1.2m and maximum inner diameter of 16.5cm.

Sustainable Management of Root-knot Nematodes in Tomatoes: Effects of Inoculum Levels under Polyhouse Conditions in Northeast India

The study aims to evaluate the impact of different inoculum levels of root-knot nematodes (Meloidogyne spp.) on tomato plants under polyhouse conditions in Northeast India. The research provides early predictions of nematode infestation severity and guides farmers on sustainable management practices, including biological control, to keep nematode populations below the economic threshold. Soil samples from key tomato-growing areas in Nongpoh, East Khasi Hills, and West Jaintia Hills districts of Meghalaya were collected, and inoculum levels ranging from 500 to 8000 J2 were tested using completely randomized design. The study found a significant increase in root gall index, egg mass production, and nematode population with higher inoculum levels. Even low inoculum levels (500 J2) caused notable damage to the plants. These findings underscore the importance of managing nematode populations early to reduce crop losses and highlight the need for efficient, low-inoculum control strategies. This study contributes to the sustainable management of nematodes in agricultural practices.

Impact of shifting patterns of the South Asian High on interannual variability of Indian summer monsoon rainfall in homogeneous regions

AbstractThe movement and intensity indices of the South Asian High (SAH), an upper‐level anticyclonic‐circulation over the Tibetan Plateau, play a crucial role in Indian summer monsoon rainfall (ISMR) during June–September. The present study aims to document (i) the association between SAH and ISMR in the periods of June–July–August (JJA) and July–August–September (JAS), and (ii) the ISMR changes at different spatial and temporal scales. The Bayesian change‐point detection method identifies 1981 as change point and the dataset has been split into two groups (past climate:1940–1980 and current climate:1981–2020) to analyze temporal variations in ISMR. Results indicate that the northwest–southeast index (INW–SE), north–south index (INS) and intensity index (IINT) of the SAH are strongly correlated (˜0.67, ˜0.60, and ˜0.51, respectively) with ISMR whereas the east–west index (IEW) is negatively correlated (˜−0.52) during the JAS season. This relation was stronger in the past climate than the current climate, except for the IINT index during the JAS season. The INW–SE and INS indices are closely associated with all‐India, northwest India (NWI), and central India (CI) rainfall, whereas IINT is associated with south peninsular India (SPI) during the JAS season. The increased rainfall over NWI and SPI in the current climate is strongly associated with positive INS and IINT indices, respectively, during the JAS season. The northeast India (NEI) rainfall did not show any association with SAH indices; however, the IEW is strongly associated with increased NEI rainfall during El Niño years. A significant positive (negative) relation between meridional (zonal) wind shear and SAH indices except the IEW index is observed. Further, the positive (negative) SAH indices favor more (moderate) ISMR due to strong positive (negative) moisture anomalies. The study demonstrates the movement and intensity of the SAH in the dynamical shifts of seasonal rainfall patterns across the Indian homogeneous regions.

Three-Dimensional Discontinuum Modeling and Rigid Block Stability Analysis of a Group of Three Caverns for Hydroproject in Northeast India

Abstract This paper presents various methods for calculating the factor of safety (FOS) and utilizes the Isoblock method to analyze the stability of underground powerhouse caverns located in the North-East state of India. A three-dimensional discontinuum analysis simulates the stability of the downstream sidewall, upstream sidewall, and crown of the caverns. The results indicate that the powerhouse cavern contains approximately 2.36% unstable blocks, while the Main Inlet Valve (MIV) and Transformer Caverns exhibit 0.14% and 0.84% unstable blocks, respectively. A comprehensive parametric analysis investigates the impact of joint stiffness, joint friction angle, in-situ stress, cover depth, and the orientation of the cavern's longer axis on stability. The findings reveal that the cavern's stability is significantly influenced by variations in lateral stress ratio and the direction of in-situ principal stress. Stability is optimized at stress ratios between 1.2 and 1.8, with maximum instability observed in the powerhouse cavern, correlating with its larger size. Notably, the stability of the crown is greater than that of the sidewalls, particularly when the cavern orientation is aligned between N68°E and N78°E. The study underscores the importance of these factors in the design and stability assessment of underground structures, providing valuable insights to enhance their safety and reliability. This analysis highlights the necessity for considering joint stiffness and in-situ stress orientations in future designs to mitigate risks associated with instability.