Photoperiod-modulated instar-specific clock-shifting in the circadian protein and amino acid rhythms in the larval segmental muscle of Bombyx mori

The photoperiod-modulated clock-shifting in the circadian protein rhythm was studied in the segmental muscle of Bombyx mori. The analysis of phase response curves of the fourth instar rhythm revealed that the muscle tissue completes six protein synthetic cycles (PS cycles) under normal 12 hr light and 12 hr dark cycle (LD), 8 cycles each under continuous light (LL) and continuous dark (DD) conditions. The fifth instar protein rhythm showed seven PS cycles each under LD and DD conditions, but only six under LL. The protein rhythm gets clock-shifted in instarspecific and photoperiod-specific fashions. In the fourth instar, both LL and DD conditions advanced the 24 hr free running time of the rhythm by six hours and set it at 18 hr, but in the fifth instar it is delayed by 4 hr and set at ~28 hr under LL, but remained unchanged under DD. Comparative analysis of protein and amino acid profiles shows that the photoperiod modulates the protein rhythm by altering the rate of amino acid mobilization

Photoperiod-induced clock-shifting in the circadian protein and amino acid rhythms in the larval fat body of silkworm, Bombyx mori

The photoperiod-induced clock-shifting in the free running time of the circadian protein and amino acid rhythms was studied in the larval fat body of Bombyx mori. The analysis of peaks and troughs of phase response curves of the rhythm revealed that the fourth and fifth instar larvae grown under normal 12 h light and 12 h dark cycle (LD) showed 7 protein synthetic cycles, while those reared under continuous light (LL) recorded 9.5 cycles in fourth instar and 8 in fifth instar. Under continuous dark (DD), the protein rhythm maintained 8 cycles in fourth instar and 7.5 cycles in fifth instar. Clearly, both LL and DD conditions advance the 24-h free running time of the protein rhythm by durations ranging from 1.6 to 6.5 h. Comparative analysis of protein and amino acid rhythms shows that the photoperiod modulates the free running time of the former by altering the rate of amino acid mobilization

Photoperiodic modulation of circadian rhythms in the silk gland protein profiles of Bombyx mori and its influence on the silk productivity and quality

Circadian rhythms in the silk gland protein profiles of Bombyx mori were analyzed under 12 h light and 12 h dark cycle (LD), continuous light (LL) and continuous dark (DD) conditions. The phase response curves of protein rhythms indicate the prevalence of a series of silk cycles, each comprising three phases; transcription, translation and consolidation of silk proteins. In the 24h- protein rhythm, the silk cycle repeats every 3h, 42 m under LD, 2h, 36m under LL and 3h under DD. The light and dark conditions advanced the rhythm of each silk cycle by 48m and 24m respectively. As a result the silk gland completes 7 rounds of protein synthesis under LD, 9 rounds under LL and 8 rounds under DD during the 24h-free running time of the rhythm. The light-induced clock-shift in the protein rhythm caused significant gains in economic parameters of sericulture with positive signals for enhancing silk productivity and quality

VLSI Implementation of Encoder and Decoder for Advanced Communication Systems

Forward Error Correction (FEC) schemes are an essential component of wireless communication systems.Present wireless standards such as Third generation (3G) systems, GSM, 802.11A, 802.16 utilize some configuration of convolutional coding. Convolutional encoding with Viterbi decoding is a powerful method for forward error correction. The Viterbi algorithm is the most extensively employed decoding algorithm for convolutional codes which comprises of minimum path and value calculation and retracing the path. The efficiency of error detection and correction increases with constraint length. In this paper the convolutional encoder and viterbi decoder are implemented on FPGA for constraint length of 9 and bit rate ½

Impact of photoperiod on circadian sucrose and sucrase rhythms in the digestive system of silkworm, Bombyx mori.

The impact of photoperiod on circadian sucrose and sucrase rhythms were analyzed in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release or uptake cycles in gut lumen. The gut wall comprised 6 sucrose synthetic cycles (SS cycles) under LD, LL and 5 under DD. The 24 hr rhythm of LD and LL was clock shifted to 28.8 hr under DD. In gut content, the sucrose rhythm showed 7 sucrose uptake cycles (SUcycles) under LD, 6 under LL and 5 under DD and the 24 hr rhythm of LD was clock shifted to 28.0 hr under LL and 34 hr under DD. In the gut wall sucrase rhythm maintained 7 SES cycles under LD and DD and 9 cycles under LL and its 24-hr rhythm is advanced to 18.2 hr. In the gut lumen 5 SER cycles under LD, 8 under LL and 6 under DD and its rhythm is advanced to 15 hr under LL and 20 hr under DD. Further analysis of data showed that LD favoured both synthesis and uptake of sucrose while LL, favoured the sucrase synthesis and its release

Ab initio Molecular Dynamical Investigation of the Finite Temperature Behavior of the Tetrahedral Au19_{19} and Au20_{20} Clusters

Density functional molecular dynamics simulations have been carried out to understand the finite temperature behavior of Au$_{19}$ and Au$_{20}$ clusters. Au$_{20}$ has been reported to be a unique molecule having tetrahedral geometry, a large HOMO-LUMO energy gap and an atomic packing similar to that of the bulk gold (J. Li et al., Science, {\bf 299} 864, 2003). Our results show that the geometry of Au$_{19}$ is exactly identical to that of Au$_{20}$ with one missing corner atom (called as vacancy). Surprisingly, our calculated heat capacities for this nearly identical pair of gold cluster exhibit dramatic differences. Au$_{20}$ undergoes a clear and distinct solid like to liquid like transition with a sharp peak in the heat capacity curve around 770 K. On the other hand, Au$_{19}$ has a broad and flat heat capacity curve with continuous melting transition. This continuous melting transition turns out to be a consequence of a process involving series of atomic rearrangements along the surface to fill in the missing corner atom. This results in a restricted diffusive motion of atoms along the surface of Au$_{19}$ between 650 K to 900 K during which the shape of the ground state geometry is retained. In contrast, the tetrahedral structure of Au$_{20}$ is destroyed around 800 K, and the cluster is clearly in a liquid like state above 1000 K. Thus, this work clearly demonstrates that (i) the gold clusters exhibit size sensitive variations in the heat capacity curves and (ii) the broad and continuous melting transition in a cluster, a feature which has so far been attributed to the disorder or absence of symmetry in the system, can also be a consequence of a defect (absence of a cap atom) in the structure.Comment: 7 figure

Molecular Exploration of Guava (Psidium guajava L.) Genome Using SSR and RAPD Markers: A Step towards Establishing Linkage Map

In the present study, molecular evaluation of two guava mapping populations (MP), MPI comprising 94 F1 progenies and MPII comprising 46 F1 progenies, was carried out using simple sequence repeat (SSR) and random amplified polymorphic DNA (RAPD) markers. A pseudo-test cross strategy was implemented where 'Kamsari' X 'Purple Local' and 'Purple Local' X 'Allahabad Safeda' were crossed, and, these showed variation in fruit quality traits such as seedstrength (hardness/softness), fruit weight, TSS and pulp color. A set of 30 RAPD markers was used for genotyping MPI while a set of 55 SSR markers was used for genotyping MPII. In case of MPI, 30 RAPD markers generated 214 scorable markers, of which 80 markers were specific to 'Kamsari', 14 markers to 'Purple Local' and the remaining 120 were intercross markers. As for MPII, 55 polymorphic SSR markers resulted in generation of 207 alleles (with a maximum of 4 alleles and a minimum of 3 alleles per locus), of which 108 alleles were specific to 'Purple Local' while 99 were specific to 'Allahabad Safeda'. Genotypic data thus generated can be further exploited for constructing genetic linkage maps and mapping complex QTLs governing fruit quality traits in guava.

Stability of binary complexes of Pb(II), Cd(II) and Hg(II) with maleic acid in TX100-water mixtures

Binary complexes of maleic acid with toxic metal ions such as Pb(II), Cd(II) and Hg(II) have been studied in 0.0-2.5% v/v tritonX-100 (TX100) - water media at 303 K  at an ionic strength of 0.16 M. The active forms of the ligand are LH2, LH- and L2-. The derived ‘best fit’ chemical speciation models are based on crystallographic R-factors, χ2 and Skewness and Kurtosis factors. The predominant species formed are of the type ML2, ML2H and ML3. The trend in variation of complex stability constants with change in the mole fraction of the medium is explained on the basis of prevailing electrostatic and non-electrostatic forces. The species distribution as a function of pH at different compositions of TX100-water mixtures and plausible speciation equilibria are presented and discussed. KEY WORDS: Maleic acid, TritonX-100, Toxic metal ions, Mole fraction, Binary complexes Bull. Chem. Soc. Ethiop. 2014, 28(3), 383-391.DOI: http://dx.doi.org/10.4314/bcse.v28i3.

DEVELOPMENT AND VALIDATION OF A DISSOLUTION METHOD FOR FROVATRIPTAN TABLETS BY REVERSED PHASE UPLC

Objective: The main objective of the method was to develop a simple, rapid, efficient and reproducible, stability indicating reverse phase ultra performance liquid chromatography (RP-UPLC) method for the estimation of frovatriptan in tablet dosage form.Methods: The RP-UPLC method for estimation of frovatriptan (FRT) in their tablets was carried out on Acquity UPLCTM, BEH C-18 (100 × 2.1 mm, 1.7 µm) column using 0.1% trifluroacetic acid buffer and a mixture of methanol and acetonitrile (50:50) using isocratic program. The flow rate of the mobile phase was 0.2 mL min-1and detection wavelength was carried out at 244 nm. Total runtime is 3 minutes for chromatographic run. The method was validated in terms of specificity, linearity, accuracy, precision and robustness as per ICH guidelines.Results: The method was found to be linear in the range of 1.41-3.67 μg mL-1. Recovery was found to be in the range of 97.8-101.8%. Relative standard deviation for precision and intermediate precision was found to be less than 3%. The developed method was successfully applied for the estimation of frovatriptan in tablet formulation and average dissolution rate was found to be 93%. The results obtained from the validation experiments prove that the developed method is suitable for routine analysis.Conclusion: The developed RP-UPLC method was simple, rapid, accurate, and precise for the estimation of dissolution rate in frovatriptan tablet dosage form.Â

Comparative studies on mydriatic effect of tropicamide 0.8% and phenylephrin 5.0% in teenagers & geriatric people

Prospective study on the comparison of mydiriatic effect of Tropicamide 0.8% and Phenylephrine 5% in teenagers and geriatric people was carried out in suthrama Eye Hospital madanapalle, India. The main objective of this study was to compare the mydriatic effect of a combination of drug in teenagers and geriatric people. It also evaluated the ADR’s produced and the efficacy of the drug in two age groups. In this study population majority of the subjects were female in group A and male in group B. Among the whole population under study in group A and B no one has reported with any case of congenital anomalies. A number of ADR’s are reported but no serious adverse events had occurred. The study was carried out in 100 eyes ie. 50 subjects whom are divided into 2 groups based on age. The comparison of mydriatic effect was done in each group after instilling one drop of a combination of 0.08% Tropicamide and 0.5% Phenynilephrine. The pupillary size where measured before and after administration of drug and the results were compared. The results showed that there is a large difference in the normal pupil size between teenagers and geriatric people. After dilation the difference in pupil size was statistically significant among the two groups. The study concludes that the pupillary dilation produced by administering 0.8% Tropicamide and 5% Phenylephrine produces higher mydriatic effect in teenagers than geriatric people