Isolation, identification and culture of the marine rotifer Colurella adriatica Ehrenberg, 1831 (Family: Lepadellidae) from Andaman & Nicobar Islands: A promising live feed for larval rearing of high value shellfishes and finfishes

An extremely small rotifer was isolated from the micro zooplankton samples collected during February, 2014 from Havelock islands of Andaman and Nicobar Islands. The species was identified as Colurella adriatica Ehrenberg, 1831 (Family: Lapadellidae). Its lorica length under culture period ranged from 47.530 to 98.868 μm and width from 34.308 to 56.277 μm. The size of the eggs, neonates and adults are also documented. Comparison of size of C. adriatica with Brachionus plicatilis (L type) and B. rotundiformis (S and SS type) revealed that C. adriatica is smaller in length and width than the SS-type rotifer which is currently used as a first feed in marine tropical fish larval rearing. However, the larvae of many marine food fishes including groupers and high value marine ornamental fishes are unable to consume the SS-type rotifers as a first feed due to their extremely small mouth gape. The culture of C. adriatica was carried out using Nannochloropsis oculata Diet-I), N. oculata and yeast (0.01g/litre) (Diet-II), Yeast (0.01g/litre) alone (Diet-III). Average population density of C. adriatica with these diets reached a maximum of 1000 nos. of individuals /ml on 10th day of culture on feeding with Diet-I; 950 nos. /ml on 14th day (Diet-II) and 650 nos. /ml on 15th day of culture (Diet-III). Diet I &II and Diet II &III did not show any significant difference (P>0.05) whereas, Diet I and III showed significant difference (P<0.01). Preliminary studies of C. adriatica as a feed to the larvae of Stenopus hispidus, Lysmata amboinensis and Pomacentrus caeruleus showed better survival than larvae fed with B. routundiformis during first phase of larval rearing

Johnson-Kendall-Roberts theory applied to living cells

Johnson-Kendall-Roberts (JKR) theory is an accurate model for strong adhesion energies of soft slightly deformable material. Little is known about the validity of this theory on complex systems such as living cells. We have addressed this problem using a depletion controlled cell adhesion and measured the force necessary to separate the cells with a micropipette technique. We show that the cytoskeleton can provide the cells with a 3D structure that is sufficiently elastic and has a sufficiently low deformability for JKR theory to be valid. When the cytoskeleton is disrupted, JKR theory is no longer applicable

Fluctuation spectrum of fluid membranes coupled to an elastic meshwork: jump of the effective surface tension at the mesh size

We identify a class of composite membranes: fluid bilayers coupled to an elastic meshwork, that are such that the meshwork's energy is a function $F_\mathrm{el}[A_\xi]$ \textit{not} of the real microscopic membrane area $A$, but of a \textit{smoothed} membrane's area $A_\xi$, which corresponds to the area of the membrane coarse-grained at the mesh size $\xi$. We show that the meshwork modifies the membrane tension $\sigma$ both below and above the scale $\xi$, inducing a tension-jump $\Delta\sigma=dF_\mathrm{el}/dA_\xi$. The predictions of our model account for the fluctuation spectrum of red blood cells membranes coupled to their cytoskeleton. Our results indicate that the cytoskeleton might be under extensional stress, which would provide a means to regulate available membrane area. We also predict an observable tension jump for membranes decorated with polymer "brushes"

Measurement of the emission spectrum of a semiconductor laser using laser-feedback interferometry

The effects of optical feedback (OF) in lasers have been observed since the early days of laser development. While OF can result in undesirable and unpredictable operation in laser systems, it can also cause measurable perturbations to the operating parameters, which can be harnessed for metrological purposes. In this work we exploit this ‘self-mixing’ effect to infer the emission spectrum of a semiconductor laser using a laser-feedback interferometer, in which the terminal voltage of the laser is used to coherently sample the reinjected field. We demonstrate this approach using a terahertz frequency quantum cascade laser operating in both single- and multiple-longitudinal mode regimes, and are able to resolve spectral features not reliably resolved using traditional Fourier transform spectroscopy. We also investigate quantitatively the frequency perturbation of individual laser modes under OF, and find excellent agreement with predictions of the excess phase equation central to the theory of lasers under OF

Assignment of the Human and Mouse Prion Protein Genes to Homologous Chromosomes

Purified preparations of scrapie prions contain one major macromolecule, designated prion protein (PrP). Genes encoding PrP are found in normal animals and humans but not within the infectious particles. The PrP gene was assigned to human chromosome 20 and the corresponding mouse chromosome 2 using somatic cell hybrids. In situ hybridization studies mapped the human PrP gene to band 20p12→pter. Our results should lead to studies of genetic loci syntenic with the PrP gene, which may play a role in the pathogenesis of prion diseases or other degenerative neurologic disorders

Mixed-Integer Linear Programming for Vehicle Routing Problem with Simultaneous Delivery and Pick-Up with Maximum Route-Length

The vehicle routing problem with simultaneous delivery and pick-up (VRPSDP) is the problem of optimally assimilating goods collection and distribution, when no priority constraints are imposed on the order in which the vehicle must perform the operations. This paper considers an additional constraint of maximum route length in VRPSDP. We develop a mixed-integer linear programming model for VRPSDP with an additional constraint of maximum route length. The results are encouraging for a sample benchmark data set

Persistence of frequently transmitted drug-resistant HIV-1 variants can be explained by high viral replication capacity

Background: In approximately 10% of newly diagnosed individuals in Europe, HIV-1 variants harboring transmitted drug resistance mutations (TDRM) are detected. For some TDRM it has been shown that they revert to wild type while other mutations persist in the absence of therapy. To understand the mechanisms explaining persistence we investigated the in vivo evolution of frequently transmitted HIV-1 variants and their impact on in vitro replicative capacity. Results: We selected 31 individuals infected with HIV-1 harboring frequently observed TDRM such as M41L or K103N in reverse transcriptase (RT) or M46L in protease. In all these samples, polymorphisms at non-TDRM positions were present at baseline (median protease: 5, RT: 6). Extensive analysis of viral evolution of protease and RT demonstrated that the majority of TDRM (51/55) persisted for at least a year and even up to eight years in the plasma. D

Evaluation of drug promotional brochures in a tertiary teaching hospital of Kannur, India

Background: Pharmaceutical industries worldwide are heavily involved in aggressive drug promotions. WHO has framed guidelines for ethical drug promotion in 1988. The transparency of pharmaceutical advertisements is important because decision of the physician is likely to be influenced by the claims made by the pharmaceutical companies in the promotional drug brochures and pharmaceutical industries treat their marketing material as “educational material” for doctors. Authors did this study to analyze the information given on drug promotional brochures by the drug companies using ethical criteria of drug promotion by WHO 1988 and to verify the authenticity of the claims given by the pharmaceutical companies in drug promotional brochures.Methods: Cross sectional study extending from 1/8/2012 to 31/7/2013. 612 drug promotional brochures satisfied our inclusion criteria. Drug brochures were analyzed with WHO ethical criteria 1988 and further categorizing the data into type of claims, number and source of references. Validity of journal articles were checked by using a validity measure developed by Cardarelli.Results: Total 612 brochures satisfied inclusion criteria. INN was mentioned in 93.8% of collected brochures. Brand name was mentioned in 100% brochures. Content of active ingredients was mentioned in 92% of brochures. Name of the other ingredients known to cause problem 28.4% of brochures. Dosage form or regimen was mentioned in 23.2% of brochures. Approved therapeutic use mentioned in 65.7% brochures. Side effects and major adverse drug reactions were mentioned in 31.4% brochures. Precautions and contraindications and warnings were mentioned in 30.4% drug promotional brochures. Drug interactions were mentioned in 26.5% brochures. Name and address was mentioned by 69.1% brochures. There were 1144 claims and 739 references. Efficacy claims were 84.88% of the total claims. Main source of reference was from journal articles (74.1%) and among them 49.65% were randomized control trials. Only 47.94 % of the journal references were valid.Conclusions: Brochures were lacking in vital information which included contraindication, warning, precaution, name of the other ingredients known to cause problem hence companies were found violating WHO ethical criteria. Claims were not well supported with references. Less than half of the given journal references were only valid. This study highlights the need of healthcare professionals to remain cautious about promotional material presented by pharmaceutical representatives

cAMP-Signalling Regulates Gametocyte-Infected Erythrocyte Deformability Required for Malaria Parasite Transmission.

Blocking Plasmodium falciparum transmission to mosquitoes has been designated a strategic objective in the global agenda of malaria elimination. Transmission is ensured by gametocyte-infected erythrocytes (GIE) that sequester in the bone marrow and at maturation are released into peripheral blood from where they are taken up during a mosquito blood meal. Release into the blood circulation is accompanied by an increase in GIE deformability that allows them to pass through the spleen. Here, we used a microsphere matrix to mimic splenic filtration and investigated the role of cAMP-signalling in regulating GIE deformability. We demonstrated that mature GIE deformability is dependent on reduced cAMP-signalling and on increased phosphodiesterase expression in stage V gametocytes, and that parasite cAMP-dependent kinase activity contributes to the stiffness of immature gametocytes. Importantly, pharmacological agents that raise cAMP levels in transmissible stage V gametocytes render them less deformable and hence less likely to circulate through the spleen. Therefore, phosphodiesterase inhibitors that raise cAMP levels in P. falciparum infected erythrocytes, such as sildenafil, represent new candidate drugs to block transmission of malaria parasites