Northern Parts Of India Research Articles

Knowledge and awareness regarding hepatitis B infection amongst dental students in northern parts of India: A cross section study

Hepatitis B virus transmission in a dental setting more commonly occurs due to inadequate/improper use of safety measures by the dentist. This particular study evaluated the hepatitis B virus infection related awareness among dental graduates. A validated questionnaire regarding the awareness about hepatitis infection and various infection control measures was distributed among the students of different year of study in undergraduate bachelor dental graduate program. Final year students showed an increased awareness when compared to third year students. There is need for improving the knowledge among the nonclinical students, mainly on transmission of virus through salivary contact. The overall awareness among the students is only fairly satisfying, which signifies the need for continued infection control education among the students. Keywords: Knowledge, Awareness, Dental students, Hepatitis B.

The story of the lost twins: decoding the genetic identities of the Kumhar and Kurcha populations from the Indian subcontinent

BackgroundThe population structure of the Indian subcontinent is a tapestry of extraordinary diversity characterized by the amalgamation of autochthonous and immigrant ancestries and rigid enforcement of sociocultural stratification. Here we investigated the genetic origin and population history of the Kumhars, a group of people who inhabit large parts of northern India. We compared 27 previously published Kumhar SNP genotype data sampled from Uttar Pradesh in north India to various modern day and ancient populations.ResultsVarious approaches such as Principal Component Analysis (PCA), Admixture, TreeMix concurred that Kumhars have high ASI ancestry, minimal Steppe component and high genomic proximity to the Kurchas, a small and relatively little-known population found ~ 2500 km away in Kerala, south India. Given the same, biogeographical mapping using Geographic Population Structure (GPS) assigned most Kumhar samples in areas neighboring to those where Kurchas are found in south India.ConclusionsWe hypothesize that the significant genomic similarity between two apparently distinct modern-day Indian populations that inhabit well separated geographical areas with no known overlapping history or links, likely alludes to their common origin during or post the decline of the Indus Valley Civilization (estimated by ALDER). Thereafter, while they dispersed towards opposite ends of the Indian subcontinent, their genomic integrity and likeness remained preserved due to endogamous social practices. Our findings illuminate the genomic history of two Indian populations, allowing a glimpse into one or few of numerous of human migrations that likely occurred across the Indian subcontinent and contributed to shape its varied and vibrant evolutionary past.

Temporary reduction in air pollution due to anthropogenic activity switch-off during COVID-19 lockdown in northern parts of India.

Due to fast and deadly spread of corona virus (COVID-19), the Government of India implemented lockdown in the entire country from 25 April 2020. So, we studied the differences in the air quality index (AQI) of Delhi (DTU, Okhla and Patparganj), Haryana (Jind, Palwal and Hisar) and Uttar Pradesh (Agra, Kanpur and Greater Noida) from 17 February 2020 to 4 May 2020. The AQI was calculated by combination of individual sub-indices of seven pollutants, namely PM2.5, PM10, NO2, NH3, SO2, CO and O3, collected from the Central Pollution Control Board website. The AQI has improved by up to 30–46.67% after lockdown. The AQI slope values − 1.87, − 1.70 and − 1.35 were reported for Delhi, − 1.11, − 1.31 and − 1.04 were observed for Haryana and − 1.48, − 1.79 and − 1.78 were found for Uttar Pradesh (UP), which may be attributed to limited access of transportation and industrial facilities due to lockdown. The ozone (O3) concentration was high at Delhi because of lesser greenery as compared to UP and Haryana, which provides higher atmospheric temperature favourable for O3 formation. The air mass back trajectory (AMBT) analysis reveals the contribution of air mass from Europe, Africa and Gulf countries as well as local emissions from Indo-Gangetic Plain, Madhya Pradesh and Maharashtra states of India.

Long-term (2008–2017) analysis of atmospheric composite aerosol and black carbon radiative forcing over a semi-arid region in southern India: Model results and ground measurement

To achieve an in-depth understanding of radiative forcing due to aerosols is a crucial challenge for climate change studies. The first-ever long-term measurement of direct shortwave composite and black carbon aerosol radiative properties over a semi-arid region, Anantapur, in southern India is presented. Long-term variations in Aerosol Optical Depth (AOD) and Black Carbon (BC) mass concentration from December 2007 to November 2017 are discussed with specific emphasis on intra-seasonal variation in aerosol optical properties, meteorology, transport pathways, and their implications for direct short wave radiative forcing over Anantapur. The intra-seasonal mean AOD showed strong seasonal dependence with the highest (0.47 ± 0.03) during summer and lowest (0.28 ± 0.03) during the monsoon. Meanwhile, the intra-seasonal mean (±σ) BC mass concentration was about 3.57 ± 0.45, 2.60 ± 0.58, 1.22 ± 0.18 and 2.24 ± 0.28 μg m−3 during winter, summer, monsoon and post-monsoon respectively. Furthermore, there is an obvious temporal variation in intra-seasonal BC mass concentration during the dry season (winter and summer). To be more specific, the intra-seasonal mean (±σ) BC mass concentration before 2012 (after 2012) during the dry season was about 3.37 ± 0.7 μg m−3 (2.80 ± 0.58 μg m−3), respectively. Concentration weighted trajectory analyses (CWT) revealed that the air masses originated from the continental and polluted environments located in the central and northern parts of India (except monsoon), in regulating BC mass concentration over measurement location. Further, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) derived aerosol vertical extinction profiles (532 nm) showed that majority aerosols (>250 Mm−1) are confined within 2 km from the surface during winter while in summer particles are distributed throughout the profile (~6 km) with extinction coefficient varying between 200 and 250 Mm−1. The Santa Barbara Discrete Ordinate Radiative Transfer (SBDART) model estimated intra-seasonal mean direct shortwave composite aerosol radiative forcing (DARF) in the atmosphere (ATM) was about 31.13 ± 3.36, 34.82 ± 3.89, 17.10 ± 1.15, and 17.44 ± 1.81 Wm-2 during winter, summer, monsoon and post-monsoon, respectively. The positive signs of ATM forcing in all seasons indicate a warming of the atmosphere, and the corresponding heating rate was around a factor of two higher during the dry season (0.92 ± 0.12 Kday−1) than the wet season (monsoon and post-monsoon) (0.49 ± 0.04 Kday−1). The intra-seasonal mean BC forcing in ATM before 2012 (After 2012) during the dry season was about 24.14 ± 2.85Wm-2(20.09 ± 2.59Wm-2), respectively. The contribution of BC alone to the composite forcing during the study period over the station was ~68%. These findings would be helpful for regional climate studies and making air pollution control policy over the region.

Frontline Publishers of Punjabi Language Books

Publishing industry plays a vital role to spread knowledge. In modern days many local publishers are making knowledge available to the society through their native languages. Punjabi is one of the most popular languages of North Indian states. Many publishers from Punjab, Chandigarh, and Delhi are publishing books in Punjabi. The present study is attempted to provide the overview and analyse the growth and contribution of publishing books in Punjabi by various types of publishers for the decade 2004-2013. The study presents different categories of publishers with the number of books, major publishers of Punjabi books, the contribution of literary, government and academic institutions as publishers and geographical distribution of Punjabi books from Northern parts of India. The study reveals that most of the books have been published in Punjabi by commercial publishers. Punjab is the leading region to publish maximum books in Punjabi as compared to other states and ‘Lokgeet Prakashan’ is the top publisher among them all. This is the first study assessing book publishers of Punjabi books and a useful source of information for practitioners and academics interested in Punjabi language publications.

Quantification of heat wave occurrences over the Indian region using long-term (1979–2017) daily gridded (0.5° × 0.5°) temperature data—a combined heat wave index approach

In the changing climate scenario, the changing heat wave frequency and magnitude have a direct impact on the agriculture, society, economic, and public health. Hence, development of easy and effective tools is essential for quantifying the heat wave incidences for better planning and management towards reducing the impacts of heat waves. In the present study, Climate Prediction Centre (CPC) global daily maximum temperature data along with the long-term normal data for the period 1979–2017 were used for quantification of heat wave conditions. Spatial and temporal sub-setting was carried out to restrict our study within the Indian region and March–July period, respectively. Based on heat wave criteria prescribed by the India Meteorological Department, different heat wave parameters, viz. frequency, magnitude, and extent, were estimated. A new approach, i.e. combined heat-wave index (CHI), was proposed to quantify the impact of heat wave in a profound manner. The efficacy of the overall method of assessing the impact of heat wave had increased by using this new approach. It was found that Rajasthan, Punjab Haryana, and Madhya Pradesh experienced high frequency as well as magnitude of heat wave, while it was lower in north-east, peninsular, and parts of northern India during our study period. The trend analysis for the heat wave parameters along with CHI was carried out over the Indian region during the last 39 years. The increasing trends were found over Rajasthan, Haryana, Punjab, East Madhya Pradesh, and Orissa, while places like Uttar Pradesh, Bihar, Chhattisgarh, Telangana, and Andhra Pradesh showed decreasing trend over the last 39 years. Peninsular and north-east India showed almost no trend regarding heat wave. Further, the month with the maximum contribution towards the seasonal heat wave and its deviation was also estimated. It was observed that the month of May was contributing most over parts of north-western and central India, while it was June in Punjab, Haryana, and western Rajasthan. Hence, the present methodology may be adopted for better planning and management of heat waves.

Optimization of process parameters on lipid biosynthesis for sustainable biodiesel production and evaluation of its fuel characteristics

The isolation of ten different cyanobacteria were carried out from northern parts of India and among them the cyanobacterium with maximum specific growth rate (0.246 day−1) was selected for the present study. The strain was further identified using morphometric and molecular analysis using 16S rDNA sequencing and was found to be related with Leptolyngbya sp. (GenBank accession no.: KF953500). The analysis of biomass composition showed ash content, amount of carbohydrate, lipid content, amount of protein, and moisture were found to be 6.8, 27.20, 18.30, 45.70, and 2% respectively. Over 26.6% increment in lipid content was evidenced when the strain was grown in BG11 medium augmented with salinity (25 mM sodium chloride) as compared to BG11 medium without sodium chloride. The unsaturated fatty acids was found 1.39 times higher than saturated fatty acids in KF953500. The lipid separated from cyanobacteria showed saponification value of 220.28, iodine value of 84.08, cetane number of 52.16, degree of unsaturation of 84.04 (%), long-chain saturation factor of 3.09 (%) and cold-filter plugging point of −6.76 °C which are generally in covenant with international standards of biodiesel. Other biodiesel properties such as pour point, flash point, acid number, viscosity, specific gravity, and density were found to be −18 °C, 126 °C, 0.34 mg KOH/g, 4.08 mm2 s−1, 0.812, and 854 kg m−3 respectively which falls within the acceptable ranges as per ASTM D6751 and EN 14214 standards, signifying the aptness of the microalga as promising sustainable feedstock for biodiesel.

Assessing Changes in Characteristics of Hot Extremes Over India in a Warming Environment and their Driving Mechanisms

Change in hot extremes is one of the accepted evidence and also a global indicator of an anthropogenic climate change, which has serious environmental and economic impacts. In the present study, the India Meteorological Department gridded temperature data is used to characterize hot extremes over India in terms of frequency and intensity. Results provide compelling evidence that large parts of India, except the Indo-Gangetic plains, have experienced more occurrences of hot days (upsurge by 24.7%) having higher temperatures in the recent period (1976–2018), compared to the past (1951–1975), which suggests a shift in climate. Strong positive geopotential height anomalies at 500 hPa over the northern parts of India, which dynamically produces subsidence and clear sky conditions along with reduced precipitable water and depleted soil moisture are identified to be the crucial factors responsible for an increase of hot extremes in recent decades. Furthermore, the preceding December-February Niño-3.4 sea surface temperature (SST) anomalies are strongly connected with hot days frequency and the mechanism for the lag of several months is related to 3–4 months delayed response of Indian Ocean SSTs to El Niño/Southern Oscillation. Thus, post-Niño hot extremes over India can be potentially anticipated in advance and this will help society to prepare for such extremes.

Gastric cancer in Jammu and Kashmir, India: A review of genetic perspectives.

Gastric Carcinoma (GC) is one of the most common malignancies, which accounts for 6.8% of total cancer population worldwide. In India, the northeastern region has the highest gastric cancer incidence, and the Kashmir Valley has a very high incidence of gastric cancer as compared to other parts of Northern India. It exceeds 40% of total cancers with an incidence rate of 3-6-fold higher than other metro cities of India. Gastric cancer is a heterogeneous disease where most of the cases are sporadic, and <15% are due to obvious familial clustering. The heterogeneous nature of the disease can be associated with differences in genetic makeup of an individual. A better understanding of genetic predisposition toward GC will be helpful in promoting personalized medicine. The aim of this review is to analyze the development and progression of GC and to explore the genetic perspectives of the disease with special emphasis on Jammu and Kashmir, India.

Subject mapping of Punjabi language books: a bibliometric study

The study presents the subject analysis of Punjabi language books written in ‘Gurmukhi’ script from 2004-2013 covering different fields of arts and humanities, social sciences, science, engineering, and technology. The distribution of major subjects and their subdivisions were based on the Dewey Decimal Classification (DDC) 22 nd edition. The information centres, and academic institutions such as universities from the different parts of Northern India, having a good collection of Punjabi language books were the focus for data collection. The Punjabi language books publishers and several websites/resources were also consulted to get the required information. A total number of 7997 Punjabi books on different subjects published during the period 2004-2013 have been studied. The largest number of books in Punjabi [5587 (69.9%)] is published in the field of literature. Subject analysis, decadal growth, analysis of books translations from different Indic and foreign languages to the Punjabi language are also included in the study. A growth rate of 29.37% in the publication of Punjabi books is seen during the decade.

Effect of clodinafop-propargyl application on membrane leakage, phenols and antioxidant enzymes in Phalaris minor

Phalaris minor Retz. is a major weed of wheat crop in northern parts of India. Resistance of P. minor to clodinafop-propargyl - an AC Case inhibitor is widespread in northern India. A pot study was conducted to evaluate the effect of clodinafop-propargyl application on membrane leakage, phenols and antioxidant enzymes in two P. minor Retz. populations- one susceptible and other resistant to this herbicide. Clodinafop-propargyl resistant population exhibited no plant mortality at 2X dose of clodinafop but in susceptible population, there was significant reduction in plant density due to X and 2X doses of clodinafop. The membrane leakage increased with increase in clodinafop dose in susceptible and resistant P. minor populations. However, resistant P. minor population exhibited reduction in membrane leakage 10 days after spray (DAS). The phenol content was significantly higher in the leaves of clodinafop-propargyl susceptible biotype than resistant biotype and herbicide application at various doses caused significant increase in the phenol content in a dose-dependent manner in both the biotypes. At 20 DAS, catalase activity exhibited significant decrease due to X and 2X doses of clodinafop in susceptible population but its activity was at par with control when clodinafop was applied at 0.25X and 0.5X doses. Application of clodinafop at X and 2X doses decreased the catalase activity at 1-7 DAS but no significant differences in activity were observed at 10-20 DAS in case of resistant population. Activities of superoxide dismutase and peroxidase exhibited an increase in susceptible P. minor population immediately after herbicide application but were decreased after 7 DAS indicating stress levels exceeded the plant defense limit and ultimately led to plant mortality. In resistant P. minor population, there was increase in SOD and POD activity up to 20 DAS indicating its oxidative stress tolerance.

Status of women in Indian society

Women are an integral part of an Indian society. In order to understand the spirit of a civilized society it is necessary to study the history of its women folk. Indian society is patriarchal society and women have been treated as subordinate and ascribed lower status to their man counterpart. In ancient times women enjoyed a position of respect and reverence and his role as a daughter, as a wife, as a mother and above all as a house maker was well defined. A change in the status of women had occurred as a sequel to the advent of Muslims in India. The social laws and customs which came to be evolved in the changed set-up of things created in them a sense of inferiority complex. The position of women as girls’ wives and widows were reduced to that of dependents and subordinates. The status of women in India has been subjected to a lot of changes over the past few millennia. Both Muslims and Hindus fell prey to the evil practices. Opportunity of receiving education was greatly restricted. After the advent of Muslims purdah was mainly confined to the rich and well to do class of both the communities. But the working class and peasant women were free from the bondage of purdah. Child marriage had become a feature of the social life. Dowry was an old custom and gradually it became rigorous. This system was prevalent more among the rich than the commoners. Divorce and remarriage were common amongst Muslims and were prohibited to Hindu women. The Hindu women had no choice to remarry; however, remarriage was common among the manial agricultural castes. Women were generally to marry through simple ritual of Chaddar-Pauna and Kareva. Sati was prevalent in almost all the parts of India. It had become a normal feature of the Hindu and Muslim society. Jauhar was popular among Hindus (especially Rajputs). However, Muslim women also adopted this custom when they found their honor in danger. Female infanticide was practiced in most parts of northern India. In some parts of India the devdasi was sexually

Role of vorticity advection and thermal advection in the development of western disturbance during North Indian winter

Western disturbance is defined as a low on the surface or an upper air cyclonic circulation in the westerly wind regime seen over northern parts of the Indian subcontinent. These systems originate over Mediterranean Sea, Caspian Sea or Black Sea and move eastward across north India. The precipitation over the northern parts of India during the winter months of January and February could be attributed to western disturbance. Ten western disturbances which resulted in fairly widespread, moderate to heavy rainfall over north India have been studied. The data used were obtained from NCEP and IMD. The systems were traced from West Asia to Western Himalayas. It is observed that Western disturbance causes 3–4 days of scattered light to moderate precipitation and one or 2 days of moderate to heavy precipitation. The specific humidity reaches a maximum value of greater than 10 g kg−1 at 1000 hPa between 0600 and 1200 UTC, a day prior or on the day of heavy rainfall. Positive vorticity advection takes place as a WD approaches the Indian region. The maximum value of vorticity advection reaches in the range of 1–2 × 10−7 s−1 between 500 and 250 hPa. A strong differential vorticity advection is observed between lower and middle troposphere on the day of most intense and widespread precipitation. It is also observed that the updraught maximum coincides with the differential vorticity advection maximum. When the WD is active, warm and moist air advection takes place over north India, which increases with height, reaching its maximum values of 7–12 × 10−4 K s−1 at levels between 300 and 200 hPa.

Long-term (1870–2018) drought reconstruction in context of surface water security in India

Droughts in India affect food production, gross domestic product (GDP), livelihood, and socio-economic condition of a large population associated with agriculture. Recent drought (2015–2018) caused groundwater depletion and affected about one-fourth of the Indian population. However, it remains unclear if the drought of 2015–2018 was among the most severe droughts that occurred in India. Here we use a long-term (1870–2018) data to identify the top five (“deadly”) meteorological/hydrological droughts based on overall severity score in the last century and half period. Out of a total of 18 meteorological droughts, the deadly droughts occurred in 1899, 1876, 2000, 1918, and 1965. Similarly, the deadly hydrological droughts occurred in 1899, 2000, 1876, 1965, and 1918 during 1870–2018. All the five deadly droughts were associated with the positive phase of El Nino Southern Oscillations (ENSO). Results show that the relationship between ENSO and monsoon (June to September) precipitation in India has weakened while the role of Indian and Atlantic Oceans have strengthened during the recent decades. Notwithstanding the longest (41 months) duration, the 2015–2018 drought did not feature among the deadly droughts. The 2015–2018 drought affected surface (reservoir storage) and groundwater availability in both southern and northern parts of India and was linked to El-Nino and Indian Ocean Dipole. Droughts and rapidly declining groundwater together can pose serious challenges to water security in India.

Satellite-based monitoring of recent heavy flooding over north-eastern states of India in July 2019

South-west monsoon of 2019 advanced towards northern parts of India during the first week of July. Heavy-to-very-heavy rainfall events during July 05–16 resulted in severe flooding over Bihar and Assam and caused huge damage in the form of life and property. More than 90 lakhs people have been affected, and about 100 causalities have been reported in Bihar and Assam due to severe flooding. Results presented in this short communication highlight the importance of space-borne near real-time monitoring of flood events. It is reported that few districts of Assam and Bihar received cumulative rainfall in excess of 1200 mm from multiple heavy rainy events during July 05–16, 2019. Heaviest rainfall events were reported on July 06, 11 and 13. Few districts of Assam and Bihar experienced daily rainfall in excess of 300 to 400 mm during these heavy rainy days with peak hourly rainfall exceeding 50 mm at few synoptic hours. Discharge from Kosi and Brahmaputra rivers combined with heavy cumulative rainfall from multiple rainy episodes during July 05–16 resulted in severe flooding over Assam and Bihar causing losses to life and property.

Impact of Deadly Dust Storms (May 2018) on Air Quality, Meteorological, and Atmospheric Parameters Over the Northern Parts of India.

The northern part of India, adjoining the Himalaya, is considered as one of the global hot spots of pollution because of various natural and anthropogenic factors. Throughout the year, the region is affected by pollution from various sources like dust, biomass burning, industrial and vehicular pollution, and myriad other anthropogenic emissions. These sources affect the air quality and health of millions of people who live in the Indo‐Gangetic Plains. The dust storms that occur during the premonsoon months of March–June every year are one of the principal sources of pollution and originate from the source region of Arabian Peninsula and the Thar desert located in north‐western India. In the year 2018, month of May, three back‐to‐back major dust storms occurred that caused massive damage, loss of human lives, and loss to property and had an impact on air quality and human health. In this paper, we combine observations from ground stations, satellites, and radiosonde networks to assess the impact of dust events in the month of May 2018, on meteorological parameters, aerosol properties, and air quality. We observed widespread changes associated with aerosol loadings, humidity, and vertical advection patterns with displacements of major trace and greenhouse gasses. We also notice drastic changes in suspended particulate matter concentrations, all of which can have significant ramifications in terms of human health and changes in weather pattern.

Influence of tropical-extratropical interactions on the dynamics of extreme rainfall event: A case study from Indian region

A diagnostic investigation of an extreme rainfall episode that occurred over the central and north Indian region is carried out in this study using data from a suite of observations from space-borne instruments and the reanalysis datasets. This event is unique in the sense that the organized tropical and extratropical forcing stimulated the intense rainfall on 01 Jan 2012. The WindSat (multi-frequency polarimetric microwave radiometer) observations indicate the source of the moisture flux coming from the adjoining tropical Ocean. The dynamical and thermo-dynamical contributions are evaluated based on the atmospheric instability analysis using the Atmospheric Infrared Sounder (AIRS) and reanalysis datasets by computing various stability indices such as total totals (TT) index, Potential Vorticity (PV), static stability and the Convective Available Potential Energy (CAPE). High TT index values (>40 K) are observed both in satellite and reanalysis data indicating thermodynamic instability. PV intrusion to low latitudes is also observed with extreme rainfall occurrence ahead of the PV tongue. The vertical structure of PV intrusion shows remarkable features with enhanced upward motions ahead of the intrusion representing the dynamical instability. The reduced static stability, increased CAPE and upper-level cyclonic anomalies together with enhanced moisture in the lower troposphere coming from the adjoining tropical Indian Ocean regulate the amplitude and region of occurrence of the extreme rainfall. Therefore, this study identifies the significant implications of tropical and extra-tropical influences that generate the thermodynamical and dynamical instabilities for the occurrence of the extreme rainfall event over the Central and Northern parts of India.

Multi-year satellite observations of tropospheric $$\hbox {NO}_{2}$$ NO 2 concentrations over the Indian region

An assessment of satellite-derived long-term tropospheric nitrogen dioxide ( $$\hbox {NO}_{2})$$ data is performed over the Indian region and their implications on the regional air quality are discussed. The Indo-Gangetic plain (IGP) shows an increasing trend in $$\hbox {NO}_{2}$$ of the order of $$3\times 10^{13}\hbox { mol/cm}^{2}/\hbox {yr}$$ . The pixel-wise (0.25 km) trend for the period 2005–2014 reveals various regions having increased rates of pollution over the study period. Further, the mean seasonal concentrations of $$\hbox {NO}_{2}$$ are segregated for different parts of the country including oceanic regions and the trends are brought out. The highest rate of increase of tropospheric $$\hbox {NO}_{2}\,(2\times 10^{14}\,\hbox {mol}/\hbox {cm}^{2}/\hbox {yr}$$ ) is seen around coal mining areas and certain industrial areas such as ports and thermal power stations. Using the data spanning 10 years, the wavelet analysis is carried out to study the influence of semi-annual oscillations (SAO) on trace gas concentrations in different parts of the country. The study reveals that the SAO are stronger in the northern parts of India, including IGP and western India, whereas South India and oceanic regions are having very low SAO component and strong annual oscillation component.

Clinico-Radiological Outcome Analysis in Craniovertebral Junction Diseases: An Institutional Experience of 38 Patients in a Tertiary Care Centre

Craniovertebral junction diseases, although considered rare, are common in northern parts of India. This study was conducted to evaluate the clinico-radiologic and surgical outcome of patients with a minimum follow-up of 1 year. Our study also compared bony fusion among various techniques of posterior fusion. This retrospective study was performed with 38 patients who met the inclusion criteria for analysis. These patients were contacted by telephone and letters, and their clinical examination and radiologic investigations were performed at a follow-up visit. The preoperative, postoperative, and follow-up clinical evaluations of the patients were done using the Nurick grading system. The age range was 4-60 years with an average of 20.5 years. There were 31 male and 7 female patients, with a male:female ratio of 4.43:1. There were 13 cases of fixed atlantoaxial dislocation (AAD), 17 cases of mobile AAD, 6 cases of traumatic AAD, and 2 cases of postinfective AAD. The majority of these patients (n= 29; 76.31%) had neck pain and cerebellovestibular disturbances (n= 27; 71.1%). Sphincter disturbances were observed in 9 patients. An increase in craniovertebral angle was observed in postoperative period in all patients. Initially, 84% of the patients had a poor Nurick grade; this was reduced to 28% after the surgical intervention. One hundred percent bony fusion was attained in patients who underwent rigid fixation technique, and 80% was attained using a semirigid fixation technique. The key to successful management of craniovertebral junction disease is individualized selection of judicious surgical intervention from various available techniques.

Influence of the Pacific–Japan Pattern on Indian Summer Monsoon Rainfall

Abstract This study discusses the impact of the Pacific–Japan (PJ) pattern on Indian summer monsoon (ISM) rainfall and its possible physical linkages through coupled and uncoupled pathways. Empirical orthogonal function analysis of 850-hPa relative vorticity over the western North Pacific (WNP) is used to extract the PJ pattern as the leading mode of circulation variability. The partial correlation analysis of the leading principal component reveals that the positive PJ pattern, which features anticyclonic and cyclonic low-level circulation anomalies over the tropical WNP and around Japan respectively, enhances the rainfall over the southern and northern parts of India. The northwestward propagating Rossby waves, in response to intensified convection over the Maritime Continent reinforced by low-level convergence in the southern flank of westward extended tropical WNP anticyclone, increase rainfall over southern peninsular India. Meanwhile, the anomalous moisture transport from the warm Bay of Bengal due to anomalous southerlies at the western edge of the low-level anticyclone extending from the tropical WNP helps to enhance the rainfall over northern India. The atmospheric general circulation model forced with climatological sea surface temperature confirms this atmospheric pathway through the westward propagating Rossby waves. Furthermore, the north Indian Ocean (NIO) warming induced by easterly wind anomalies along the southern periphery of the tropical WNP–NIO anticyclone enhances local convection, which in turn feeds back to the WNP convection anomalies. This coupled nature via interbasin feedback between the PJ pattern and NIO is confirmed using coupled model sensitivity experiments. These results are important in identifying new sources of ISM variability/predictability on the interannual time scale.