Variator Research Articles

Commentary: Consensual ophthalmotonic reaction.

Intraocular pressure (IOP) change in the untreated fellow eye accompanied by a corresponding IOP reduction in the operated eye has been identified as the “consensual ophthalmotonic reaction” (COR), and the terminology was coined by Weekers in 1924.[1] This response was initially observed after contusion, ocular compression, tonography, and cauterization of the sclera.[2] In 1927, Wilmer published the first report on COR after a fistulating surgery in experimental animals.[3] After that, multiple studies have reported the possibility of IOP variation in the fellow eye following unilateral glaucoma surgery, including not only trabeculectomy, but glaucoma drainage device implantations, filtering canaloplasty, and microshunt implantations as well.[4] However, whether there is an IOP increase, decrease, or no change in the fellow eye after glaucoma surgery is still controversial. These contrasting results could be due to differences in the type of glaucoma, preoperative IOP, surgical technique, antimetabolite dosage and duration, time point of observation, and outflow facility of the untreated fellow eye. The postulated mechanisms behind COR include neuronal, hormonal, and cytokine regulation of aqueous flow dynamics.[5] Nevertheless, the exact mechanism is yet to be elucidated. A decrease in IOP in the fellow eye could be associated with improved patient compliance to the antiglaucoma therapy or the effect of systemic absorption of the medications. Also, it could result from a “regression to the mean” effect, as trabeculectomy is often planned when the IOP is high on the variation curve.[6] Regarding COR with topical medications, Newman et al.[7] observed that the IOP reduction in contralateral eyes was found to be associated with timolol only and not prostaglandins or carbonic anhydrase inhibitors. A similar decrease in IOP in the fellow eye has also been reported after laser trabeculoplasty, which might be due to the effects of the systemic release of humoral agents, such as matrix metalloproteinase, and improved medication compliance.[8] An increase in the fellow eye IOP following glaucoma surgery has been observed in the present study. We have also observed an IOP rise in a significant number of patients in the unoperated eye in the early postoperative period after unilateral trabeculectomy, though we do not have published data. Different theories have been postulated that may explain this finding. Weekers[1] explained the possible existence of COR in which activation of the nervous system increased the fellow eye aqueous production. Diestelhorst and Krieglstein[5] also postulated that unilateral filtration surgery triggers a central nervous system-mediated reflective increase in aqueous flow in the unoperated fellow eye to maintain physiological stability. In an animal experiment, a supraoptic controlling pathway has been suggested to lead to an IOP rise in response to water drinking after unilateral optic nerve sections.[9] A few studies described that underperfusion of the trabecular meshwork by aqueous humor in the operated eye and increased extracellular trabecular meshwork material deposition induces a reflex mechanism mediated by specialized cells in the scleral spur that can lead to decreased outflow in the fellow eye.[10] Another hypothesis was an increase in the prostaglandin level in response to the inflammation in the operated eye.[11] Other possible explanations include a postoperative presumed steroid response or withdrawal of antiglaucoma medications.[12] No studies have attributed the increase in IOP in the fellow eye to one factor. In the literature, post-surgical COR is found to occur at an earlier time frame than post-laser COR, which might suggest the role of mechanical triggers rather than chemical triggers in post-surgical COR. The predominance of one mechanism occurring due to a particular intervention may guide the IOP varia tion in the contralateral eye. Further prospective studies and a much more detailed macroscopic overview are needed to delineate the underlying mechanisms and the exact biological role of post-surgical COR. The take-home message is that the fellow eye needs to be carefully monitored after unilateral glaucoma surgery. The fellow eye may be the only eye with vision or the better eye of the two. Also, fellow eyes may be already glaucomatous, that failure to monitor and recognize IOP rise may delay appropriate management leading to glaucoma progression. It is recommended to inform the patient about the possibility of IOP variation in the other eye after glaucoma surgery and the need for multiple visits, especially in the early postoperative period. Another relevant message is that the fellow eyes should not be preferably used as a control in studies assessing the IOP outcomes of a particular treatment or intervention.

The use of gender-neuter marking in Brazilian Portuguese tweets: a sociolinguist approach

This research investigates gender-neuter marking in Brazilian Portuguese, a recent lin guistic variation that has divided many opinions in Brazilian social and political circles until now. The Theory of Varia tion (LABOV, 2008 [1972]; WEINREICH; LABOV; HERZOG, 2006 [1968]), with a focus on Communities of Practice (ECKERT; MCCONNELL-GINET, 1992a, 1992b), supports the descriptio n and analysis conducted. To observe the variant, we opted for the social network Twitter, from which we collected 3,446 tweets produced by three subjects during the second half of 2020 who explic itly expressed a preference for the use of the neuter pronouns “Elu,” “Ilu,” “El” or “Ile.” As a selection criterion, we considered tweets containing adjectiv es, nouns, and pronouns whose referent was a human, and morphological markers carrying gender distinction. The predictor variables stipulated were morphosyntactic class, lexical ite m, the tweet topic, parti cipant, and the reference performed by gender marks (generic or specific). The sample was submitte d through the RStudio program, version 4.1.2, through which the proposed statisticaltreatment w as c arried o ut. T he r esults reveal a d isadvantage r egarding g ender-neuter marking for all partic ipants, not showing optimistic estimates about any specific word. They also pointed out the adjective class, the affective relationship and identity topics, and the generic reference performed by gender marking as conditioners of gender-neuter employment

Investigations of HSC punching shear capacity in flat slabs

Slabs punching shear capacity for normal strength concrete (NSC) and high strength concrete has been investigated in this paper. Due to the significance of concrete technology in the construction industry, more attention has been paid to high strength concrete in this paper. Then, detailed comparison is carried to evaluate the outcome by referring to several existing standards. Slabs punching tests have been collected from the reported results in the literature. Forty-seven tested slab specimens have been grouped from the available published information. In this work, the collected specimens are studied thoroughly, and a conclusion has been drawn from the preliminary investigation that punching shear failure is a common feature in the forty-seven specimens. The collected concrete slab specimens have diversified cylinder compressive strength ( ) ranged from 14.4 MPa to 119 MPa. However, the application of ( ) in existing codes is restricted to a limit as mention hereafter. American Concrete Institute (ACI-14) limits the practical application of to 69MPa, while The Australian Concrete Structures Standard (AS-94) limits to 50 MPa. The recent evolvement in concrete technology has made the production of HSC with much greater than the aforementioned values affordably reachable. Therefore, the present research attempts to bridge this gap and goes beyond the standards restrictions. This has been achieved by proposing a new design equation for punching shear through applying a regression analysis. The accuracy of the proposed equation and the existing equations have been examined by utilizing statistical analysis [Arithmetical mean ( ), Variation (VAR), Standard Deviation (SD) and Coefficient of Variation (COV)] to the punching shear failure strength values. The proposed method results for , VAR, SD and COV are 1.575, 0.364, 0.1299 and 23.128% respectively, and these are smaller when compared with the other 6 existing code methods.

Comparing 3DVAR and hybrid radar data assimilation methods for heavy rain forecast

Radar data are assimilated into numerical prediction models to improve precipitation forecasts using three-dimensional (3D) variational (VAR) and hybrid data assimilation (DA) methods. The effect of radar DA (RDA) and prediction accuracy according to DA methods are evaluated by conducting experiments of three heavy rainfall events and analyzing the spatial pattern of accumulated precipitation, profiles of hydrometeors, and cloud microphysical processes. Increments of the initial analysis revealed that the hybrid method simulated the convective band, wind convergence in front of the cold front and a higher amount of water vapor mixing ratio compared to 3DVAR. Based on numerical experiments, the root mean square error of the total cumulative precipitation in 3DVAR was 9.68 mm lower than that of the no-RDA experiment (CTRL), whereas that of the Hybrid was 11.12 mm lower than that of CTRL. RDA improved precipitation forecasts, and Hybrid showed better precipitation forecast accuracy than 3DVAR. Although RDA indirectly changed the water vapor, rain, snow, and graupel mixing ratios, the change in the water vapor amount was the major factor affecting microphysical processes. The increase (decrease) in the water vapor mixing ratio had the greatest impact on precipitation formation (dissipation), whereas the effect of snow, rain, and graupel mixing ratios was relatively small. The results indicate that it is critical to create an environment in which water vapor can transform into precipitating hydrometeors and the hydrometeors can grow through cloud microphysical processes. The accuracy of heavy rain forecast can be improved by hybrid DA method, which can consider the model error in real time, making it more adaptable to the day-to-day changing weather conditions.

Construction of the Core Collection of Catalpa fargesii f. duclouxii (Huangxinzimu) Based on Molecular Markers and Phenotypic Traits

To promote the conservation and utilization of Catalpa fargesii f. duclouxii (Huangxinzimu) germplasm resources, a total of 252 accessions were used to construct a preliminary core collection according to phenotypic traits and single nucleotide polymorphism (SNP) markers. In this study, 24 phenotypic traits, namely, 9 quantitative traits and 15 qualitative traits, were investigated. The core collection of C. fargesii f. duclouxii (Huangxinzimu) was constructed to remove redundant samples from the collected materials. First, the phenotypic core collection, with a sample proportion of 30, consisting of 24 clones, was constructed according to two genetic distances (Euclidean distance and Mahalanobis), four system clustering methods (the unweighted pair-group average method, Ward’s method, the complete linkage method, and the single linkage method), and three sampling methods (random sampling, deviation sampling, and preferred sampling). The best construction strategies were selected for further comparison. Three core collections (D2C3S3-30, D2C3S3-50, and D2C3S3-70) were constructed according to the optimal construction strategy at three sampling proportions. The core collection D2C3S3-30 with the best parameters was evaluated by using six parameters: the mean difference percentage (MD), variance difference percentage (VD), periodic rate of range (CR), changeable rate of the coefficient of variation (VR), minimum rate of change (CRMIN), and maximum rate of change (CRMAX). Three core collections (M-30, M-50, and M-70) were constructed by molecular markers, and the optimal core collection M-30 was selected by using five parameters, namely, Ho, He, PIC, MAF, and loci. The combination of D2C3S3-30 and M-30 was used to construct the final core collection DM-45, 45 samples representing the complete range of phenotypic and genetic variability. In this study, phenotypic traits combined with molecular markers were used to construct core collections to effectively capture the entire range of trait variation, effectively representing the original germplasm and providing a basis for the conservation and utilization of C. fargesii f. duclouxii (Huangxinzimu).

Diallel Analysis for Area, Chlorophyll and Temperature of Flag Leaf in Bread Wheat under Well Watered and Drought Stress Conditions

To study genetic analysis of some physiological traits of drought stress in wheat using diallel techniques, an experiment was performed on ten bread wheat genotypes as parents and their 45 F1 hybrids in a randomized complete block design with three replicates under well-watered and drought stress conditions at the Research Farm of Faculty of Agriculture, Sohag University, Egypt during season of 2018/19. The results showed significant differences between the genotypes (G), Parents (P), F1 crosses, P vs. F1, GCA and SCA under well-watered and drought stress in the flag leaf area (FLA), flag leaf chlorophyll content (FLCC) and flag leaf temperature (FLT), except FLCC for F1 crosses exhibited insignificant differences. The significant differences were found in the interaction of SCA × Env., in all studied traits and GCA × Env., for FLT., indicating the involvement of both additive and dominance gene action in their inheritance. The most desirable heterotic effects were considered as the largest positive heterosis estimates for FLA and FLCC, and the lowest negative for FLT. The parent numbers P9, P8 and P3 were the best general combiner for FLA under normal irrigation and drought stress. While the parents P2, P7 and P9 were the best general combiner for FLCC, under normal irrigation and (P1, P2 and P3) under drought stress. Therefor the parents P1, P4 and P5 were the best general combiner for FLT under normal irrigation, also the P3, P4 and P5 were the best general combiner for FLT under drought stress conditions. Under normal irrigation and drought stress conditions as well as the combined data, the additive genetic components of variation (VA) in F1 ’s was much greater than dominance component (VD), as expressed by the (VA/VD) ratio which was more than unity for the FLA, and FLT under normal irrigation and their combined. This indicates that the additive gene effects in F1 crosses are more important than dominance and plays the major role in the inheritance of these studied traits.

Mean Field Bias-Aware State Updating via Variational Assimilation of Streamflow into Distributed Hydrologic Models

When there exist catchment-wide biases in the distributed hydrologic model states, state updating based on streamflow assimilation at the catchment outlet tends to over- and under-adjust model states close to and away from the outlet, respectively. This is due to the greater sensitivity of the simulated outlet flow to the model states that are located more closely to the outlet in the hydraulic sense, and the subsequent overcompensation of the states in the more influential grid boxes to make up for the larger scale bias. In this work, we describe Mean Field Bias (MFB)-aware variational (VAR) assimilation, or MVAR, to address the above. MVAR performs bi-scale state updating of the distributed hydrologic model using streamflow observations in which MFB in the model states are first corrected at the catchment scale before the resulting states are adjusted at the grid box scale. We comparatively evaluate MVAR with conventional VAR based on streamflow assimilation into the distributed Sacramento Soil Moisture Accounting model for a headwater catchment. Compared to VAR, MVAR adjusts model states at remote cells by larger margins and reduces the Mean Squared Error of streamflow analysis by 2–8% at the outlet Tiff City, and by 1–10% at the interior location Lanagan.

Characterization of wheat germplasm conserved in the Indian National Genebank and establishment of a composite core collection

AbstractThe use of untapped plant genetic resources of wheat (Triticum spp.) can enhance its productivity. In the present study, we characterized 22,416 accessions of three different species of wheat conserved in the Indian National Genebank using 23 qualitative and 12 quantitative traits to develop a core set. These accessions were highly diverse on the basis of range, coefficient of variation, and Shannon–Weaver diversity index. Initial grouping was done on the bases of species and origin, and thereafter, agromorphological data were used to develop core sets for each species group using the heuristic approach with PowerCore. Finally, a composite core set was constituted comprising 2,226 accessions, which included 1,779 accessions of bread wheat (T. aestivum L.), 394 of durum wheat [T. turgidum L. subsp. durum (Desf.) van Slageren], and 53 of emmer wheat [T. dicoccon Schrank; syn. T. turgidum L. subsp. dicoccon (Schrank) Thell]. The core set was validated under field conditions. Also, the coincidence rate of range (CR) (bread wheat, 85.78%; durum wheat, 87.52%; and emmer wheat, 95.34%) and variable rate of the coefficient of variation (VR) (bread wheat, 174.9%; durum wheat, 136.5%; and emmer wheat, 105.81%) were more than the threshold values of 80 and 100%, respectively. The phenotypic correlations among different traits attributable to coadapted gene complexes and total variation shown by principal components in the entire set were also mostly preserved in the core set. The composite wheat core and the trait‐specific germplasm sets identified would serve as valuable resources for global wheat improvement programs.

Genetic variance in fitness and its cross-sex covariance predict adaptation during experimental evolution.

The additive genetic variation (VA ) of fitness in a population is of particular importance to quantify its adaptive potential and predict its response to rapid environmental change. Recent statistical advances in quantitative genetics and the use of new molecular tools have fostered great interest in estimating fitness VA in wild populations. However, the value of VA for fitness in predicting evolutionary changes over several generations remains mostly unknown. In our study, we addressed this question by combining classical quantitative genetics with experimental evolution in the model organism Tribolium castaneum (red flour beetle) in three new environmental conditions (Dry, Hot, Hot-Dry). We tested for potential constraints that might limit adaptation, including environmental and sex genetic antagonisms captured by negative genetic covariance between environments and female and male fitness, respectively. Observed fitness changes after 20 generations mainly matched our predictions. Given that body size is commonly used as a proxy for fitness, we also tested how this trait and its genetic variance (including nonadditive genetic variance) were impacted by environmental stress. In both traits, genetic variances were sex and condition dependent, but they differed in their variance composition, cross-sex and cross-environment genetic covariances, as well as in the environmental impact on VA .

Effects of ambient temperatures on evolutionary potential of reproductive timing in boreal passerines.

Many populations need to adapt to changing environmental conditions, such as warming climate. Changing conditions generate directional selection for traits critical for fitness. For evolutionary responses to occur, these traits need to be heritable. However, changes in environmental conditions can alter the amount of heritable variation a population expresses, making predictions about expected responses difficult. The aim of this study was to evaluate the effects of ambient temperatures on evolutionary potential and strength of natural selection on the timing of reproduction in two passerine birds breeding in boreal forests. Long-term data on individually marked Willow Tits Poecile montanus (1975-2018) and Great Tits Parus major (1969-2018) were analysed with random regression animal models to assess if spring temperatures affect the expressed amount of additive genetic variation (VA ) and heritability (h2 ) in the timing of breeding. We assessed if ambient temperatures of different seasons influenced the direction and strength of selection on breeding time. We also evaluated if the strength of selection covaried with evolutionary potential. Levels of VA or h2 expressed in laying date were unaffected by spring temperatures in both study species. Selection for earlier breeding was found in the Willow Tit, but not in the Great Tit. In the Willow Tit, selection for earlier breeding was more intense when the temperatures of following autumns and winters were low. Different measures of evolutionary potential did not covary strongly with the strength of selection in either species. We conclude that there is no or little evidence that climate warming would either constrain or promote evolutionary potential in timing of breeding through changes in amount of genetic variance expressed in boreal Willow and Great Tits. However, selection on the timing of breeding, a life-history event taking place in springtime, is regulated by temperatures of autumns and winters. Rapid warming of these periods have thus potential to reduce the rate of expected evolutionary response in reproductive timing.

Construction and validation of core collections in Pisum sp. using different methodologies

Core collections contribute to a better utilization of accessions in breeding programs. Eighty-five accessions from a collection of Pisum germplasm were evaluated during 2015 and 2016. Phenotypic values of 12 morphological traits were measured and genotypic values (BLUP) were calculated. Molecular characterization was performed assaying a total of 15 SSR and 25 SRAP primer combinations. Four Cluster Analysis (phenotypic values, genotypic values, molecular markers and consensus) and four strategies to determine the number of accessions selected (constant, logarithmic, proportional and maximization strategies) were applied to construct 16 core collections. Validation of the core collections were performed through Mean difference percentage (MD), Variance difference percentage (VD), Coincidence rate of range (CR) Variable rate of coefficient of variation (VR), Shannon diversity index (SW) and the Taxonomy coverage (TC). The logarithmic strategy with data on genotypic values was the best strategy, while the least strategy was the proportional strategy with molecular marker data.

Кинематика автовариаторного привода машин

Кинематика автовариаторного привода машин

A Special Points-Based Hybrid Prediction Strategy for Dynamic Multi-Objective Optimization

Dynamic multi-objective optimization problem (DMOP) is such a type of optimization problems that multiple contradictory objectives change over time. This paper designs a special point-based hybrid prediction strategy (SHPS) integrated into the decomposition-based multi-objective optimization algorithm with differential evolution (MOEA/D-DE) to handle DMOPs, which is denoted as MOEA/D-DE-SHPS. In the SHPS, when historical information is insufficient to establish prediction model of population prediction strategy (PPS), the prediction (PRE) and variation (VAR) method are adapted to generate the initial population of the new environment. Meanwhile, the PPS predicts the whole population of new environment according to the history information collected from past environments; therefore, once collected historical information is inaccurate, the predicted population may be located in the wrong search region. To overcome the shortcoming, we propose the special point-based strategy in which the initial population of the new environment consists of two parts of individuals: the predicted special points and the predicted population by PPS (except the special points). The empirical results show that MOEA/D-DE-SHPS is promising for handling DMOPs.

Effect of migration and environmental heterogeneity on the maintenance of quantitative genetic variation: a simulation study.

The paradox of high genetic variation observed in traits under stabilizing selection is a long-standing problem in evolutionary theory, as mutation rates appear too low to explain observed levels of standing genetic variation under classic models of mutation-selection balance. Spatially or temporally heterogeneous environments can maintain more standing genetic variation within populations than homogeneous environments, but it is unclear whether such conditions can resolve the above discrepancy between theory and observation. Here, we use individual-based simulations to explore the effect of various types of environmental heterogeneity on the maintenance of genetic variation (VA ) for a quantitative trait under stabilizing selection. We find that VA is maximized at intermediate migration rates in spatially heterogeneous environments and that the observed patterns are robust to changes in population size. Spatial environmental heterogeneity increased variation by as much as 10-fold over mutation-selection balance alone, whereas pure temporal environmental heterogeneity increased variance by only 45% at max. Our results show that some combinations of spatial heterogeneity and migration can maintain considerably more variation than mutation-selection balance, potentially reconciling the discrepancy between theoretical predictions and empirical observations. However, given the narrow regions of parameter space required for this effect, this is unlikely to provide a general explanation for the maintenance of variation. Nonetheless, our results suggest that habitat fragmentation may affect the maintenance of VA and thereby reduce the adaptive capacity of populations.

Free vibration analysis for a non-contact piezoelectric motor modulated by electromagnetic field

For a non-contact piezoelectric motor modulated by electromagnetic field, the equation of the free vibration for the driving system of the motor is given. Using the boundary conditions and continuity conditions, the natural frequencies and mode functions of the driving system are obtained. The vari ation law of the natural frequency is investigated, when the system parameters of the driving system are changed in a certain range. The results show that the change of the system parameters of piezoelectric stacks and driving beams has obvious effects on odd order natural frequencies of the driving system; the change of the system parameters of the center shaft have obvious effects on even order natural frequencies; In the odd order modes, the maximum vibration amplitude of the driving system occurs at the junction of the driving beam and the center shaft. It is conducive to output of the motor rotation angle. All the results are useful for design and control of operating performance of the motor.

A state estimation approach based on stochastic expansions

This paper presents a new approach for state estimation problems. It is based on the representation of random variables using stochastic functions. Its main idea is to expand the state variables in terms of the noise variables of the system, and then estimate the unnoisy value of the state variables by taking the mean value of the stochastic expansion. Moreover, it was shown that in some situations, the proposed approach may be adapted to the determination of the probability distribution of the state noise. For the determination of the coefficients of the expansions, we present three approaches: moment matching (MM), collocation (COL) and variational (VAR). In the numerical analysis section, three examples are analyzed including a discrete linear system, the Influenza in a boarding school and the state estimation problem in the Hodgkin–Huxley’s model. In all these examples, the proposed approach was able to estimate the values of the state variables with precision, i.e., with very low RMS values.

Case report: uncommon insertion of the extensor pollicis longus muscle: clinical and anthropological significance of this variation

The role of the hand width anthropometric measurement in the estimation of grip strength is seen to be approximately fifty percent. Variation in the extensor pollicis longus muscle is important in daily life based on the fact that the thumb plays an important function, which is to grab objects and to hold them between two fingers. In this study, dissection was being performed on a male cadaver, approximately 55-year-old at the Department of Anatomy, Kocaeli University. Researchers encountered a unilateral extensor pollicis longus muscle va riation that took origin from posterior of the radius and continued at medial side of the extensor pollicis brevis muscle and then ended at the tuberculum radii, whereas the extensor pollicis longus muscle had to end at distal phalange of the thumb. Therefore, information about the anatomic variations of hand and wrist muscles is not for anatomists alone but it is also important for surgeons. For these reasons, it is necessary to follow the variations in the forearm extensor region.

Doses from radon-222 irradiation for workers of the granite mining industry

determining the integral value of annual effective dose from 222Rn for workers of the granite mining industry and assessment for the expected life effective dose from 222Rn. Materials were the results of measurements of external exposure dose of radiation measurements equiv alent equilibrium volume activity of 222Rn in workrooms and workplaces of major groups of granite quarry workers Mykolaiv region, studies EROA 222Rn air premises of these workers, research content 222Rn in drinking water. Granite quarry workers receive double radiation exposure of 222Rn due to exposure in the workplace and at home. The load in the workplace due to inhalation of 222Rn the air was (2.1 ± 0.2) mSv / year (vari ation 0.9-5.9) in a residential area - (4,1 ± 0,2) mSv/year (variation 1.8-5.9). The total annual effective dose from internal exposure from air flow and working premises and drinking water was on average (6,5 ± 0,2) mSv/year, equal to a maximum value of 20 mSv/year. The expected life for the chronic exposure dose of technological naturally occurring radioactive sources for people who work in the granite quarries and, while living in high risk from radon is in the range of 0.16-1.12 Sv. The research results indicate that in assessing the effects associated with exposure due to radon 222 contingents persons such surveys must take into account all sources of this radionuclide dose.

STUDIES ON COMPRESSION AND DRUG RELEASE CHARACTERISTICS OF XANTHIUM GUM PELLETS OF DIFFERENT COMPOSITIONS

The filler used in preparation of pellets affects physical properties, compression and drug release rates . The present investigation was aimed to develop a sustained drug delivery system for a short half life drug, Simvastatin with a view to prolong the release with a sustained release mechanism . Simvastatin is an antilipidaemic agent . Characterization of drug was done by performing the determination of solubility, melting point and FTIR spectroscopy . The prepared batches of pellets were evaluated for micromeritic study such as particle size determination, true density, bulk density, degree of compression, specific surface area and angle of repose . All the batches of pellets were compressed into tablets and evaluated for general appearance, weight vari ation, hardness, content uniformity, and dissolution study . From the results of all these studies, batch F6 was found to show the best results containing Xanthan gum ( 16 %) and Lactose monohydrates ( 8 %) and selected as an optimized batch . The optimized batc h was subjected for further studies such as Scanning Electron Microscopy ( SEM ) to demonstrate pellets morphology and FTIR to determine the drug polymer interaction . Optimized formulation was subjected to accelerate d stability study for a period of 30 days at 40 ± 2 0 C and 75 ± 5 % RH . Formulation was subjected for thickness, hardness, drug content and in - vitro drug release studies at interval of 15 and 30 days .

Chromosomal analysis and nors polymorphism of bagarius suchus (Siluriformes: Sisoridae) by conventional banding and fish techniques

In the present study, conventional staining and NORs banding as well as Fluorescence in situ hybridizat ion (FISH) using the 18S rDNA and telomeric (TTA GGG)n probes were applied to stain the chromosomes of crocodile catfish, Bagariussuchus (Siluriformes, Sisoridae) fro m the Chao Praya River, Thailand. Kidney cells of 6 male and 6 female crocodile catfishes were used as a sample. The mitotic chro mosome preparations were done directly fro m kidney cells. The results showed that the diploid chro mosome number of B. suchus was 2n=56, the fundamental numbers (NF) were 102 in both male and female. The karyotype comprises 17m+17sm+12a+10t. The nucleo lar organizer reg ions (NORs) were detected by Ag -NORs banding and 18S rDNA probe mapping. The 18S rDNA are terminally located on the short arm adjacent to the telomere of the single pair of the 1st chromosome pair whereas NOR-bearing chro mosome is only one chromosome of the 1st chromosome pair (1a 1b, poly morphic characteristic) at the subtelomeric region of the short arm. Moreover, FISH with telomeric probe showed hybridizat ion signals on each telomere of all chro mosomes and interstitial telomeric sites were not detected. There were variations in signals of FISH and their position in the karyotype along with variat ion in DNA sequences. These markers are useful for future discrimination of population of closely related species and their poly morphis m.