Technical Efficiency of Freshwater Aquaculture and its Determinants in Tripura, India

Freshwater aquaculture is an important and promising sector of the economy of Tripura State. The biophysical potential for growth in freshwater aquaculture in the state is still far from exhaustion and a faster development is required to meet the growth in demand for fish. This paper has assessed the level of technical efficiency and its determinants of small-scale fish production in the West Tripura district of the state of Tripura, India. The study is based on the cross-sectional primary data collected from 101 fish farmers through a multi-stage random sampling method. The paper has employed stochastic production frontier approach, and has followed both one-stage and two-stage procedures to analyze the determinants of TE. The TE ranges between 0.21 and 0.96 with mean of 0.66 and median of 0.71. The study has revealed the Cobb-Douglas form of stochastic frontier production function is more dependable than that of translog form under the farming conditions in the West Tripura district of Tripura state. One-stage procedure with technical inefficiency model gives reliable estimates of coefficients of stochastic frontier production function than that of two-stage procedure. Seed quality has been found as an important determinant of TE. The study has suggested that the state government needs to play a role to ascertain the supply of quality fish fingerlings at adequate time and quantity to the farmers in the study area.Agricultural and Food Policy,

Analysis of the Alignment of Micro-Steel Fibers in Admixture-Based Self-Compacting Concrete (MSFR-SCC) using NDT and Evaluation of Its Effect on the Modulus of Rupture

Self-compacting concrete (SCC) is a particular type of concrete that flows and becomes consolidated under its own weight. Various have been conducted to enhance its performance. Key developments have been the addition of fibers and replacement of the mineral admixtures; several studies have focused on varying these factors in different proportions to produce a high performance concrete. However, there is no standard mix design for self-compacting concrete containing admixtures. Therefore, optimization of the mix design is very important in order to save time and to develop an economical SCC, but there has been no detailed study of mix design and optimization of materials, and no research into the alignment and orientation of the steel fibers. Along with the uniform dispersion of fibers, few steps have been taken to optimally align the micro steel fibers, with ultrasonic pulse velocity used to justify their distribution and alignment. These factors were taken into consideration in this study. The results show that the addition of steel fibers reduces the rheological properties of the concrete by 40%-55% compared to the control mix (MC1), although all the mixtures (MC1-MX4) justified the guidelines set by EFNARC (European Federation of National Association Representing for Concrete). All the specimens failed under shear. The addition of hooked-end micro steel increased the flexural strength compared to the control mixture and a 60% increase in MX4 and 75% increase in MA7 were observed compared to MC1. The fibers were aligned along the direction of flow and the alignment properties was justified by flexural strength and UPV. A regression equation was finally developed between flexural strength and UPV for future development, which predicts the behavior of micro steel fiber reinforced self-compacting concrete (MSFRSCC)

Impact Resistance and Strength Reliability of Fiber-reinforced Concrete in Bending under Drop Weight Impact Load

This paper presents an experimental investigation on the Impact failure energy and strength reliability of fiber reinforced concrete (FRC) by using a simple drop weight test which was based on the testing procedure recommended by ACI committee 544. Two different steel fibers were used as the reinforcing material in various volume fractions such as 0%, 0.5%, 1.0% and 1.5% with a water cement ratio of 0.42. Furthermore, the two-parameter weibull distribution was used to analyze the experimental data in order to sort out a variation of test results. Using the weibull distribution, the impact failure strength reliability, in other words, the probability distribution according to which the concrete will fail, was obtained. The results indicated that the concrete containing a 1.5% volume fraction of fiber gave the best performance followed by 1.0% and 0.5% under impact loading. It was proven that the probabilistic distributions of the impact failure energy of seven types of samples approximately follow two-parameter Weibull distribution

An Experimental Study on Performance of Bacillus pumilus KC845305 and Bacillus flexus KC845306 in Bacterial Concrete

In recent years, concrete has become an important versatile construction material. This paper evaluates the strength obtained by concrete with the influence of bacteria. The bacterial strains were isolated from calcareous sludge and urea ware house. The bacterial strains were identified through 16srRNA gene sequencing as Bacillus pumilus and Bacillus flexus. Using these strains, an experiment on cylinder and prisms cast was performed. Compressive strength, split tensile and flexural tests were conducted at the age of 7, 28 and 56 days with ultrasonic pulse velocity and rebound hammer. The results were compared with Bacillus cohnii MTCC 3616 obtained from microbial type culture collection and gene bank, Chandigarh, India. Based on the experimental results, the improvement in the mechanical strength is due to the deposition of calcite crystals on the bacterial cell surfaces within the pores which enhanced the strength of concrete and reduced porosity and permeability

Study of the plutino object (208996) 2003 AZ84 from stellar occultations: size, shape and topographic features

We present results derived from four stellar occultations by the plutino object (208996) 2003~AZ$_{84}$, detected at January 8, 2011 (single-chord event), February 3, 2012 (multi-chord), December 2, 2013 (single-chord) and November 15, 2014 (multi-chord). Our observations rule out an oblate spheroid solution for 2003~AZ$_{84}$'s shape. Instead, assuming hydrostatic equilibrium, we find that a Jacobi triaxial solution with semi axes $(470 \pm 20) \times (383 \pm 10) \times (245 \pm 8)$~km % axis ratios $b/a= 0.82 \pm 0.05$ and $c/a= 0.52 \pm 0.02$, can better account for all our occultation observations. Combining these dimensions with the rotation period of the body (6.75~h) and the amplitude of its rotation light curve, we derive a density $\rho=0.87 \pm 0.01$~g~cm$^{-3}$ a geometric albedo $p_V= 0.097 \pm 0.009$. A grazing chord observed during the 2014 occultation reveals a topographic feature along 2003~AZ$_{84}$'s limb, that can be interpreted as an abrupt chasm of width $\sim 23$~km and depth $> 8$~km or a smooth depression of width $\sim 80$~km and depth $\sim 13$~km (or an intermediate feature between those two extremes)

Downregulation of urokinase plasminogen activator receptor expression inhibits Erk signalling with concomitant suppression of invasiveness due to loss of uPAR–β1 integrin complex in colon cancer cells

Cancer invasion is regulated by cell surface proteinases and adhesion molecules. Interaction between specific cell surface molecules such as urokinase plasminogen activator receptor (uPAR) and integrins is crucial for tumour invasion and metastasis. In this study, we examined whether uPAR and beta1 integrin form a functional complex to mediate signalling required for tumour invasion. We assessed the expression of uPAR/beta1 integrin complex, Erk signalling pathway, adhesion, uPA and matrix metalloproteinase (MMP) expression, migration/invasion and matrix degradation in a colon cancer cell line in which uPAR expression was modified. Antisense inhibition of the cell surface expression of uPAR by 50% in human colon carcinoma HCT116 cells (A/S) suppressed Erk-MAP kinase activity by two-fold. Urokinase plasminogen activator receptor antisense treatment of HCT116 cells was associated with a 1.3-fold inhibition of adhesion, approximately four-fold suppression of HMW-uPA secretion and inhibition of pro-MMP-9 secretion. At a functional level, uPAR antisense resulted in a four-fold decline in migration/invasion and abatement of plasmin-mediated matrix degradation. In empty vector-transfected cells (mock), uPA strongly elevated basal Erk activation. In contrast, in A/S cells, uPA induction of Erk activation was not observed. Urokinase plasminogen activator receptor associated with beta1 integrin in mock-transfected cells. Disruption of uPAR-beta1 integrin complex in mock-transfected cells with a specific peptide (P25) inhibited uPA-mediated Erk-MAP kinase pathway and inhibited migration/invasion and plasmin-dependent matrix degradation through suppression of pro-MMP-9/MMP-2 expression. This novel paradigm of uPAR-integrin signalling may afford opportunities for alternative therapeutic strategies for the treatment of cancer

Global, regional, and national burden of neurological disorders during 1990-2015 : a systematic analysis for the Global Burden of Disease Study 2015

Background Comparable data on the global and country-specific burden of neurological disorders and their trends are crucial for health-care planning and resource allocation. The Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study provides such information but does not routinely aggregate results that are of interest to clinicians specialising in neurological conditions. In this systematic analysis, we quantified the global disease burden due to neurological disorders in 2015 and its relationship with country development level. Methods We estimated global and country-specific prevalence, mortality, disability-adjusted life-years (DALYs), years of life lost (YLLs), and years lived with disability (YLDs) for various neurological disorders that in the GBD classification have been previously spread across multiple disease groupings. The more inclusive grouping of neurological disorders included stroke, meningitis, encephalitis, tetanus, Alzheimer's disease and other dementias, Parkinson's disease, epilepsy, multiple sclerosis, motor neuron disease, migraine, tension-type headache, medication overuse headache, brain and nervous system cancers, and a residual category of other neurological disorders. We also analysed results based on the Socio-demographic Index (SDI), a compound measure of income per capita, education, and fertility, to identify patterns associated with development and how countries fare against expected outcomes relative to their level of development. Findings Neurological disorders ranked as the leading cause group of DALYs in 2015 (250.7 [95% uncertainty interval (UI) 229.1 to 274.7] million, comprising 10.2% of global DALYs) and the second-leading cause group of deaths (9.4 [9.1 to 9.7] million], comprising 16.8% of global deaths). The most prevalent neurological disorders were tensiontype headache (1505 9 [UI 1337.3 to 1681.6 million cases]), migraine (958.8 [872.1 to 1055.6] million), medication overuse headache (58.5 [50.8 to 67.4 million]), and Alzheimer's disease and other dementias (46.0 [40.2 to 52.7 million]). Between 1990 and 2015, the number of deaths from neurological disorders increased by 36.7%, and the number of DALYs by 7.4%. These increases occurred despite decreases in age-standardised rates of death and DALYs of 26.1% and 29.7%, respectively; stroke and communicable neurological disorders were responsible for most of these decreases. Communicable neurological disorders were the largest cause of DALYs in countries with low SDI. Stroke rates were highest at middle levels of SDI and lowest at the highest SDI. Most of the changes in DALY rates of neurological disorders with development were driven by changes in YLLs. Interpretation Neurological disorders are an important cause of disability and death worldwide. Globally, the burden of neurological disorders has increased substantially over the past 25 years because of expanding population numbers and ageing, despite substantial decreases in mortality rates from stroke and communicable neurological disorders. The number of patients who will need care by clinicians with expertise in neurological conditions will continue to grow in coming decades. Policy makers and health-care providers should be aware of these trends to provide adequate services.Peer reviewe