Validation study of using the free volume approximation to confined thermotropic and lyotropic liquid-crystalline fluids.

We examined the accuracy of the free volume approximation (FVA) to calculate the isotropic-nematic (IN) transition properties of thermotropic and lyotropic rods between two parallel hard walls. This approximation has been proposed to ease the calculation of the confined systems. It approximates the free energy of the confined particles with a bulk free energy. It predicts a special point for these two types of liquid crystals where the first-order IN transition changes to the second one by decreasing either the temperature, the density or the pore width. This prediction is in contradiction (in spite of some qualitative agreement) with those of the other publications where the authors note that the discontinuous transition terminates at the critical point when the walls are completely impenetrable.

Trichodina amblypharyngodoni sp. n. and Trichodina hoffmani Wellborn, 1967 (Ciliophora: Trichodinidae) from the freshwater fishes in the Baikka Beel of Moulvibazar district in Sylhet division, Bangladesh

During a survey on species diversity of trichodinid ciliates from freshwater fishes in the Baikka Beel of Moulvibazar district in Sylhet division from January to December 2015, two species of ciliates were identified, of which one is new to science. Trichodina hoffmani Wellborn, 1967 is collected from the gills of Mystus tengara, and Trichodina amblypharyngodoni sp. n. is described from Amblypharyngodon mola using the silver nitrate impregnation method. T. amblypharyngodoni sp. n. is characterized by having a large, darkly stained central area; rectangularly-rounded butterspoon-shaped blade with very narrow interblade space and blunt tangent point; indistinct anterior and posterior blade apophysis, but a rounded apex near the base of the central part of denticle; slender, sometimes slightly triangular central part with rounded tip; and filamentous, curved, anteriorly directed rays with inflated tip and indistinct central groove. Based on these characters and the unique shape and absence of variability of the denticles among the silver impregnated specimens of the present species, it may be said that to a lesser extent, it resembles Trichodina prowazeki Grupcheva and Lom, 1980.

Allometric growth rate of the spinal cord in relation to the vertebral column during prenatal life in male and female goats (Capra hircus).

Total and regional allometric growth rates and termination sites of the spinal cord related to the respective vertebra were studied in 36 goat fetuses, from the Ahvaz slaughterhouse. These specimens were assigned to 3 groups, group 1 (CRL 10-20 cm), group 2 (CRL 21-30 cm), and group 3 (CRL 31-40 cm), each consisting of 6 male and 6 female fetuses. Observations in all 3 groups revealed that although the growth of the vertebral column was greater than that of the spinal cord, the difference in growth was not constant throughout the spine. While in cervical and thoracic regions the growth rate of the spinal cord in relation to the vertebral column was almost isometric, in the caudal part of the spine there was marked decline in growth of the spinal cord compared to the respective regions of the vertebral column. Craniocaudally, the allometric growth rate became drastically negative. There was no significant difference (P>0.05) between males and females. Except in thoracic region, all other regions showed significant differences (P<0.01) between similar regions in all 3 groups. In the lumbar region of group 2 no significant difference was found (P>0.05). As a consequence of the negative allometric growth of the spinal cord in relation to the vertebral column in the caudal part of the spine, the conus medullaris was displaced from S4-S5 in group 1 to S2 in group 3. No significant difference (P>0.05) between male and female fetuses concerning the termination of the spinal cord was found.

Growth and structural properties of Mg(N) (N = 10-56) clusters: density functional theory study.

Using the minima hopping global geometry optimization method on density functional potential energy surface, we have studied the structural and electronic properties of magnesium clusters for a size range of Mg(N) where N = 10-56. Our exhaustive search reveals that most of our global minima are nonsymmetric in the size range above N = 20. We elucidate the evolutionary trend of the entire series and present more details about the peculiar growth of the clusters. For N > 20, it is possible to divide the cluster into two regions: the core region and the surface region. It turns out that the growth follows a peculiar cyclic pattern where the core and surface grow alternatively. The surface energy, as a function of number of atoms shows a clear signature as the number of atoms in the core increases by one. We have also carried out stability analysis and the stable sizes(magic numbers) agree very well with the experimental magic numbers reported by Diederich [J. Chem. Phys. 2011, 134, 124302]. We point out the similarities and differences between our results and sodium clusters.

Trichodina shitalakshyae sp. n. and Trichodina acuta Lom, 1961 (Ciliophora: Trichodinidae) from the freshwater fishes in the Shitalakshya River, Bangladesh.

Two trichodinid species were identified from freshwater fishes, Mystus bleekeri and Glossogobius giuris, in the Shitalakshya River of Gazipur district, Bangladesh. Trichodina acuta Lom, 1961 is found for the first time in Bangladesh. Trichodina shitalakshyae sp. n. is characterized by having an undivided clear central area in the adhesive disc with a rounded or slightly undulated perimeter containing a few dark granules which form patches; elongated and rectangular blade with large interblade space and blunt tangent point; indistinct anterior blade apophysis and a shallow apex at the base of blade that never extends beyond the Y+1 axis; moderately wide and triangular central part with blunt point; and space between tip of ray and central clear area forms a wide impregnated ring. Based on these characters and the unique shape and absence of variability of the denticles among the silver impregnated specimens of the present species, it resembles Trichodina porocephalusi Asmat, 2001.

Routes of opioid analgesic therapy in the management of cancer pain.

BACKGROUND: The availability of various routes of administration of opioid analgesics can be confusing when determining an appropriate, efficacious, and cost-effective regimen to manage cancer pain. METHODS: The indications, contraindications, and pharmacokinetic properties of oral, intravenous, subcutaneous, transdermal, transmucosal, rectal, and perispinal routes of opioid administration are reviewed. RESULTS: To determine the most efficacious, cost-effective, and user-friendly option to manage cancer pain, several factors must be considered: the ability of the patient to use a specific type of delivery system, the efficacy of that system to deliver acceptable analgesia, the ease of use for the patient and family, the potential or actual complications associated with that system, and the cost. CONCLUSIONS: Administering opioids to manage cancer pain requires knowledge of potency relative to morphine and bioavailability of the route chosen. Changes in the route, dosage, or opioid used should be accompanied with close patient follow-up.