Remarks on Reflexive Subcategories

In this article, we study reflexive subcategories of the category of finitely generated modules over Cohen–Macaulay local rings R. One of the main results yields a complete classification of the reflexive subcategories for the case when R is a one-dimensional complete local hypersurface of finite Cohen–Macaulay representation type. The other result yields a one-to-one correspondence between the subclasses of a stable category and the reflexive subcategories over a complete local hypersurface. Then, we attempt to extend the result in Takahashi [8 Takahashi, R. (2006). Remarks on modules approximated by G-projective modules. J. Algebra 301:748–780.[Crossref], [Web of Science ®] , [Google Scholar], Proposition 4.4] to a reflexive subcategory.     

Mesophases Induced by Molecular Complexing

By mixing of potentially-mesomorphic electron donors and acceptors of the type N-(p-X-benzylidene)-p-Y-aniline, nematic and smectic liquid crystals could be induced. In the present work, the donor molecules with a dimethylamino group as X or Y and the acceptor molecule with a nitro group as X or Y were employed. The remaining terminal substituents were selected from short alkoxyl groups; namely, methoxyl, ethoxyl, and propoxyl groups. The effect of the replacement of ethoxyl group by propyl group was also studied. The induced mesophases are more deeply colored than the component compounds owing to the appearance of intermolecular charge-transfer absorption near 500 nm.     

Complexation of herbicide bentazon with native and modified β-cyclodextrin

For first time the complexation of bentazon (Btz) with native β-cyclodextrin (β-CD) and modified sulfobutylether-β-CD (SBE-CD) was studied by differential pulse voltammetry. In addition, a spectrophotometry UV–Visible study was carried out. In presence of CDs there is a decrease of the anodic peak current with the increase of the amount of CD. This decrease is due to the lower diffusion coefficient of Btz/CD complex compared with the free guest. Using the variation in current, association constants of 118 ± 20 and 317 ± 25 M^?1 for β-CD and SBE-CD were determined. The solubility of bentazon was 8 fold higher with SBE-CD as compared with bentazon-free. Phase solubility diagrams performed using UV–Vis experiments permit to obtain the same association constants which were compared with the values obtained by electrochemical techniques.     

Directional limits on persistent gravitational waves using LIGO S5 science data

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2)?Hz(-1) and 5-35×10(-49) strain(2)?Hz(-1)?sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.     

Effect of DODAB Nano-Sized Cationic Bilayer Fragments against Leishmania amazonensis

The dioctadecyldimethylammonium bromide (DODAB) is a double-chained cationic lipid with potent bactericide and fungistatic activities; however, its toxicity on protozoan parasites is still unknown. Here, we show the antileishmanial activity of DODAB nano-sized cationic bilayer fragments on stationary-phase promastigotes and amastigotes of Leishmania amazonensis, the causative agent of cutaneous leishmaniasis. Upon treatment with DODAB, we analyzed the parasite surface zeta-potential, parasite viability, cellular structural modifications, and intracellular proliferation. The DODAB cytotoxic effect was dose-dependent, with a median effective concentration (EC₅₀) of 25 µM for both life-cycle stages, comparable to the reported data for bacteria and fungi. The treatment with DODAB changed the membrane zeta-potential from negative to positive, compromised the parasite’s morphology, affected the cell size regulation, caused a loss of intracellular organelles, and probably dysregulated the plasma membrane permeability without membrane disruption. Moreover, the parasites that survived after treatment induced small parasitophorous vacuoles and failed to proliferate inside macrophages. In conclusion, DODAB displayed antileishmanial activity, and it remains to be elucidated how DODAB acts on the protozoan membrane. Understanding this mechanism can provide insights into the development of new parasite-control strategies.     

Voltammetric behavior of the transfer of mono- and polyammonium ions across a phospholipid monolayer at the nitrobenzene/water interface.

The influence of a phospholipid, dipalmitoyl phosphatidylcholine, layer at a nitrobenzenelwater interface on the transfer of tetraethylammonium ion and a polyammonium anti-fungus agent, poly[(dimethylimino)(2-oxo-1,2-ethanediyl)imino1,6-hexanediylimino (1-oxo-1,2-ethanediyl)(dimethylimino)-1,6-hexanediyl] ion, across the interface was studied by normal pulse voltammetry. When the phospholipid was adsorbed to form a monolayer at the nitrobenzenelwater interface by its addition to the organic phase, the half-wave potential in the current vs. potential curves for the transfer of tetraethylammonium ion did not change, but the limiting current was significantly decreased at certain sampling times, indicating a retarding effect of the layer on the ion-transfer. On the other hand, in the current vs. potential curves for the transfer of the polyammonium ion, no significant change in either the half-wave potential or the limiting current was observed upon adding the phospholipid, indicating that the polyammonium ion can easily permeate through the phospholipid layer. The results suggest a new application of the voltammetric technique to the study of cell membrane permeability to polyionic bioactive compounds.     

Generation in singularity categories of hypersurfaces of countable representation type

The Orlov spectrum and Rouquier dimension are invariants of a triangulated category to measure how big the category is, and they have been studied actively. In this paper, we investigate the singularity category $$\textsf {D} _{\textsf {sg} }(R)$$ of a hypersurface R of countable representation type. For a thick subcategory $${\mathcal {T}}$$ of $$\textsf {D} _{\textsf {sg} }(R)$$ and a full subcategory $$\mathcal {X}$$ of $${\mathcal {T}}$$, we calculate the Rouquier dimension of $${\mathcal {T}}$$ with respect to $$\mathcal {X}$$. Furthermore, we prove that the level in $$\textsf {D} _{\textsf {sg} }(R)$$ of the residue field of R with respect to each nonzero object is at most one.