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This paper attempts to compare some transformed ratio type estimators for estimating the population mean ... of the study variable y using information on the auxiliary variable x in the presence of non-response. A generalized transformed ratio type estimator has been proposed and its properties are discussed. Various special cases of this estimator are considered. An empirical study has been conducted with real populations to study the performance of the estimators. It has been found that the estimators due to Sisodia and Dwivedi (1981) and Upadhyay and Singh (1999) have over performed other estimators in presence of non-response. However, for optimum choice of constants the proposed estimator along with estimator due to Khare and Srivastava (1997) and regression estimators are equally efficient and over preformed other estimators. [ABSTRACT FROM AUTHOR]

In the present paper, an attempt has been made to develop two-steps calibration estimator of population mean in two-stage stratified random sampling, first by calibrating sampling design weight at psu level and second by calibrating stratum weight using known total of the auxiliary information at population level. A limited simulation study with real data has been conducted to examine the relative performance of the calibration estimators over the usual estimator of the population mean without using auxiliary information in two-stage stratified random sampling. Results of the simulation study show that two-steps calibration estimator has brought considerable improvement in the precision of the estimate of the population mean. [ABSTRACT FROM AUTHOR]

Various statistical models to study the effect of weather variables on rapeseed & mustard yield at different stages of crop and to forecast its yield for Faizabad District have been attempted. Time series data on yield for rapeseed & mustard crop of Faizabad district of Uttar Pradesh for 22 years (1990-91 to 2011-12) have been used. Weekly weather data for the period (1991-2012) on six weather variables viz. Minimum Temperature, Maximum Temperature, Relative Humidity at 7 hour, Relative Humidity at 14 hour, Sun-shine hours and Wind-Velocity of Faizabad district have been utilised for the present study. Various models have been tried to know the relationship between rapeseed & mustard crop yield by generating new weather indices from weekly data. In all, eight statistical models were developed. The model involving total of value of weather variable over weeks and linear functions of respective correlation coefficients between adjusted crop yield for trend effect and weekly data and weather variables as the independent variables has been found to be the best one (model VII & VIII) for studying the effect of individual weather variables. A forecast model has been developed to forecast the pre-harvest crop yield. The results revealed that forecast at 21st week of the crop period i.e. during third week of February before one and half months of its harvest was found to be reliable one as percent standard error of forecast was obtained to be approximately 4 percent. [ABSTRACT FROM AUTHOR]

Calibration estimation is a popular technique for increasing the precision of estimates of population parameters by using specified auxiliary information. Some ratio type estimators have been considered for estimating population mean by making use of a set of calibration constraints in stratified sampling. The estimator of variance of the proposed calibration estimator of mean is derived using a lower level calibration approach. Simulation study is used to evaluate the performances of the proposed estimators by comparing them with the usual ratio type estimators. [ABSTRACT FROM AUTHOR]

Deville and Särndal (1992) developed calibration estimator by using the auxiliary information to obtain a better estimate of the population total of study variate y. While calibration approach does not assume any explicit relationship between y and x but it assumes that only X, the population total of x is known. Prediction approach advocated by Royall and Herson (1973) leads to model based estimator of finite population under a assumption of specified super population model where xi's are supposed to be known for all i = 1, 2, 3, ..., N. Wu and Sitter (2001) proposed a design oriented model based calibration estimator of population total, when they also assumed that Xi are known for all i = 1, 2, 3, ..., N. It has been shown that these three approaches i.e. calibration approach, model based approach and model based calibration approach provides the same estimator under some situation. However, their variances are different. In the present paper, an attempt has been made to conduct a limited simulation study to examine the relative performance of the estimators based on the aforesaid three approaches. From the results of the simulation study, it has been found that calibration estimates are best. [ABSTRACT FROM AUTHOR]

Application of principal component analysis in developing statistical models for forecasting pigeon-pea yield has been demonstrated. The time series data on pigeon-pea yield and weekly data on eight weather variables viz., Minimum and maximum temperature ,Rainfall and number of Rainy days, Relative Humidity at 7hr and 14hr, Sun-Shine hours and Wind- Velocity pertaining to the period 1990-91 to 2011-12 in Faizabad district of Uttar Pradesh have been used in this study. Weather indices have been constructed using weekly data on weather variables [Agrawal et al. (1983)]. Total six models have been developed using principal component analysis of weather indices. The forecast yields have been found to be very close to the actual yield except in one or two cases. The per cent standard errors of forecast yield obtained from the model-2 and 5 have been found below 5.50 per cent in comparison to other models. Therefore, the model-2 and 5 have been found to be most appropriate on the basis of values of R2, per cent deviation of forecast, per cent root mean error (%RMSE) and per cent standard error (PSE) for the reliable forecast of pigeon-pea yield two and half months before the harvest of the crop. [ABSTRACT FROM AUTHOR]

Calibration estimation improves the precision of the estimates of population parameters by incorporating specified auxiliary information. A class of calibration estimators has been proposed for estimating the population mean by making use of a set of calibration constraints in stratified sampling. The estimator of variance of the proposed calibration estimator of the mean is derived using a lower level calibration approach. The idea is extended for stratified double sampling. A simulation study is used to evaluate the performances of the proposed estimators by comparing them with the similar estimators developed by Tracy, Singh and Arnab (2003) based on different sets of calibration constraints. [ABSTRACT FROM AUTHOR]

An application of principal component analysis for the development of suitable statistical models for preharvest forecast of rice yield based on biometrical characters has been dealt with in the present paper. The data obtained from the two experiments on rice have been utilised to develop the model. The forecast yields of based on these models have been found to be 24.25, 22.60 and 21.10 q/ha against the actual yield of 28.00, 23.56 and 21.85 q/ha, respectively, in experiment -I. For experiment -II the forecast yields were found to be 24.62, 28.06 and 29.43 q/ha against the actual yield of 28.82, 29.31 and 26.59 q/ha, respectively. These forecast yields are subject to maximum of almost 10 percent standard error. In most of the cases, the forecast yields were found to be close to the actual yield except in some cases. The values of R2, i.e. 79.80 and 72.60 for experiment -I and II, respectively, indicate the validity of the models. Statistical tool like viz. principal component analysis (PCA) has been first time applied to develop pre-harvest forecast model based on experimental data. [ABSTRACT FROM AUTHOR]

The present paper deals with the application of ratio type estimator to estimate population mean for small area on current occasion in repeated surveys. The estimation of population mean for small area on current occasion has been proposed using separate ratio-type estimator and combined ratio-type estimator. The mean square errors (MSE) of proposed estimators have also been derived and show that the estimate based on combined ratio-type estimator is more efficient than separate ratio-type estimator, under certain conditions. In addition, this theoretical result is supported by an empirical study. [ABSTRACT FROM AUTHOR]

Unlabelled: ᅟ: The purpose of the current study was to determine the accuracy of the clinical diagnosis in non-melanoma skin malignancy as confirmed by histopathological examination of the specimen. Positive predictive value (PPV) was selected as a reliable measure of diagnostic accuracy., Methods: Clinical diagnosis was made in the outpatient clinic by a consultant oral and maxillofacial surgeon. We reviewed the electronic charts of 210 patients with non-melanoma skin malignant tumours and calculated the positive predictive value of the initial clinical diagnosis. Histological confirmation for each lesion was compared with the provisional clinical diagnosis made in the clinic., Results: Of the 147 lesions provisionally diagnosed as basal cell carcinomas, 133 lesions were histologically confirmed to be basal cell carcinomas (BCC) (PPV 90.4 %). Of the 63 lesions provisionally thought to be squamous cell carcinomas, 47 lesions were histologically confirmed as squamous cell carcinomas (SCC) (PPV 74.6 %). The difference between the PPVs for the two types of malignancy in our study was not significant (p = 0.39). Statistics between our results for BCC and SCC and those reported from two other cancer institutes revealed no significant difference (p = 0.58 and 0.07)., Conclusions: The present study supports that relying on clinical diagnosis with the purpose to formalise a treatment plan for head and neck non-melanoma skin cancer is safe and efficient. This is more reliable in cases of basal cell carcinoma in comparison to suspected squamous cell carcinomas. Although positive predictive value represents a reliable measure of diagnostic accuracy, it is increased when populations with higher prevalence of the disease are studied.

Visceral leishmaniasis (VL) is a major fatal disease prevalent in North-East India, caused by a protozoan parasite Leishmania donovani. The parasite multiplies and thrives inside mammalian macrophages and is transmitted by the bite of the sandfly. Due to the unsatisfactory treatment measures, increasing drug resistance and the advent of HIV-Leishmania co-infection there has been an urgent need to develop novel drug/vaccine targets against VL. Target identification is the key step in drug discovery and proteomics seems to be a suitable strategy for it due to the availability of Leishmania major, Leishmania infantum, Leishmania braziliensis, Leishmania donovani, Leishmania mexicana and Leishmania tarentolae genome sequence. Since, majority of proteome analyses of Leishmania have, so far, been performed on whole-cell extracts; this study is dealing with the sub-proteome analysis of the membrane-enriched protein (MEP) fractions of L. donovani. The analysis of 95 protein spots of the MEPs from two dimensional (2-D) gel image through matrix asserted laser desorption ionization-time of flight/mass spectrometry (MALDI-TOF/MS) endorsed the identification of various relevant functional proteins. Out of 95 the MEP spots 72 have been identified and were classified on the basis of their biological function. Several proteins of unknown function that belong to different classes like cell signaling, transmembrane receptors, and transporters have been identified which could be the new potential therapeutic targets against VL in future. The proteome array of the MEPs contributes to further elucidation of the biological system of L. donovani as well as host-parasite relationships which may be further investigated for their crucial biological role in L. donovani for disease management., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Because of the growing concern about antibiotic resistance, we aimed to investigate whether the microbiological picture and antibiotic sensitivity of infections in the head and neck have changed in the last 30-40 years. We retrospectively studied 150 patients admitted for inpatient treatment of infections in the head and neck, and searched published reports from the last 30 - 40 years for comparison. There were 85 male and 65 female patients (mean age 39 years, range 1-95). Most infections originated from the teeth (n = 111) and skin (n = 16), and the submandibular (69%) and buccal (67%) spaces were involved most often. Multiple spaces were involved in 94 patients. Swabs were taken for culture and sensitivity in 102 cases, and microorganisms were isolated in 91 (89%), of which 67 (74%) were aerobic infections and 24 (26%) were anaerobic. Bacteria were isolated in 87 (96%) cultures of which 60 (69%) were Gram-positive. Gram-positive cocci were isolated in 62% of cultures. The most common bacteria isolated were streptococci. Seventy percent of the bacteria were sensitive to amoxicillin and 84% to amoxicillin and metronidazole; 14% (Staphylococcus aureus from infections of the skin) were resistant to penicillin. A comparison of our results with those found in previous reports shows no significant change in the microbiological picture and antibiotic sensitivity of odontogenic infections in the head and neck over the last 30 - 40 years. Amoxicillin still treats these infections effectively., (Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Leishmania donovani, a causative organism of visceral leishmaniasis (VL), is responsible for high mortality throughout the world. Due to the unsatisfactory treatment measures and increasing drug resistance, there has been an urgent need to develop novel drug/vaccine targets against VL. The aim of this study was to identify novel targets in soluble L. donovani (SLD) protein. SLD protein was isolated and resolved by two-dimensional gel electrophoresis and analyzed through MALDI-TOF/TOF-based mass spectrometry. Proteomic results identified several proteins as drug targets, Th1 stimulatory, novel, and hypothetical proteins which could have crucial biological functions in Leishmania pathogenesis.

Aims: This study aimed to identify differentially overexpressed membrane-enriched as well as cytosolic proteins in SAG sensitive and resistant clinical strains of L. donovani isolated from VL patients which are involved in the drug resistance mechanism., Methods: The proteins in the membrane-enriched as well as cytosolic fractions of drug-sensitive as well as drug-resistant clinical isolates were separated using two-dimensional gel electrophoresis and overexpressed identified protein spots of interest were excised and analysed using MALDI-TOF/TOF., Results: Six out of 12 overexpressed proteins were identified in the membrane-enriched fraction of the SAG resistant strain of L. donovani whereas 14 out of 18 spots were identified in the cytosolic fraction as compared with the SAG sensitive strain. The major proteins in the membrane-enriched fraction were ABC transporter, HSP-83, GPI protein transamidase, cysteine-leucine rich protein and 60S ribosomal protein L23a whereas in the cytosolic fraction proliferative cell nuclear antigen (PCNA), proteasome alpha 5 subunit, carboxypeptidase, HSP-70, enolase, fructose-1,6-bisphosphate aldolase, tubulin-beta chain have been identified. Most of these proteins have been reported as potential drug targets, except 60S ribosomal protein L23a and PCNA which have not been reported to date for their possible involvement in drug resistance against VL., Conclusion: This study for the first time provided a cumulative proteomic analysis of proteins overexpressed in drug resistant clinical isolates of L. donovani indicating their possible role in antimony resistance of the parasite. Identified proteins provide a vast field to be exploited for novel treatment strategies against VL such as cloning and overexpression of these targets to produce recombinant therapeutic/prophylactic proteins., (© 2010 The Authors. British Journal of Clinical Pharmacology © 2010 The British Pharmacological Society.)

Mastomys coucha and jirds (Meriones unguiculatus) were immunized with four cytokine-stimulating SDS-PAGE resolved fractions F5 (68-84 kDa), F6 (54-68 kDa), F10 (38-42 kDa) and F14 (20-28 kDa) of Brugia malayi adult worm to determine which of these fractions has the potential to influence the establishment of subsequently introduced B. malayi infection in the animals. The proteins in the fractions were analyzed by 2DE and MALDI-TOF. Immunization with F6 suppressed the establishment of third stage larva (L(3)) initiated infection in M. coucha (64%; P<0.01) and jird (42%; P<0.01). Survival of intraperitoneally implanted adult worms in M. coucha was lowered by F6 (72%; P<0.01) and F14 (66%; P<0.05) but not by F5 and F10. Immunization with F6 intensely upregulated both Th1 (IFN-gamma, TNF-alpha, IL-1 beta, IL-2, IL-6, IgG1, IgG2a and lymphoproliferation) and Th2 (IgG2b and IL-10) responses and NO release. Immunostimulatory proteins HSP60, intermediate filament protein, and translation elongation factor EF-2 were identified in F6 fraction by 2DE and MALDI. The findings suggest that F6 protects the host from the parasite via Th1/Th2 type responses and thus holds promise for development as a vaccine.

Our earlier studies identified a fraction (F2) of Leishmania donovani soluble promastigote antigen belonging to 97.4-68 kDa for its ability to stimulate Th1-type cellular responses in cured visceral leishmaniasis (VL) patients as well as in cured hamsters. A further fractionation of F2-fraction into seven subfractions (F2.1-F2.7) and re-assessment for their immunostimulatory responses revealed that out of these, only four (F2.4-F2.7) belonging to 89.9-97.1 kDa, stimulated remarkable Th1-type cellular responses either individually or in a pooled form (P4-7). In this study these potential subfractions were further assessed for their prophylactic potential in combination with BCG against L. donovani challenge in hamsters. Optimum parasite inhibition ( approximately 99%) was obtained in hamsters vaccinated with pooled subfractions and they survived for 1 year. The protection was further supported by remarkable lymphoproliferative, IFN-gamma and IL-12 responses along with profound delayed type hypersensitivity and increased levels of Leishmania-specific IgG2 antibody as observed on days 45, 90 and 120 post-challenge suggesting that a successful subunit vaccine against VL may require multiple Th1-immunostimulatory proteins. MALDI-TOF-MS/MS analysis of these subfractions further revealed that of the 19 identified immunostimulatory proteins, Elongation factor-2, p45, Heat shock protein-70/83, Aldolase, Enolase, Triosephosphate isomerase, Disulfideisomerase and Calreticulin were the major ones in these subfractions.

Seven novel brevifoliol analogues have been synthesized by coupling brevifoliol and 2-monosubstituted-4-phenyl-1,3-oxazolidine carboxylic acid after removal of the protecting group with acid treatment. Brevifoliol and its synthesized analogues were tested for their cytotoxic activities against four different human cancer cell lines, oral (KB), breast (MCF-7), colon (CaCO2) and liver (HepG-2) as determined by MTT assay. The C-13 oxidized brevifoliol retained significant activity. Out of the seven analogues synthesized, C-13 oxidized brevifoliol-5-[N-tert-butoxycarbonyl amino-(2'R,3'S)-3'-phenyl isoserine] analogue was interesting as it exhibited selective and potent cytotoxicity against liver cancer cell line predominantly.