Prediction of the incidence of spontaneous intracerebral hemorrhage from meteorological data

We analyzed the relationship between the incidence of spontaneous intracerebral hemorrhage (ICH) and various meteorological data (daily atmospheric air pressure, air temperature, precipitation, humidity, presence of typhoons, occurrence of the rainy season, wind velocity, and wind direction) for patients at Teraoka Memorial Hospital in Shin-ichi Town, Japan, from January 1, 2001 to December 31, 2003. All data were analyzed by contingency table analysis and multivariate regression analysis. From January 1, 2002 to December 31, 2003, we identified high-risk ICH days as those days for which the preceding 3 days mean recorded air pressure of 1,015 hPa or more and then conducted a statistical comparison of the incidence of ICH on high-risk ICH days with that on the other days. Our subjects were 164 patients with ICH. The relative risk of high-risk ICH days is 1.46 (Fisher’s exact test, p = 0.04). Mann–Whitney’s U-tests indicate ICH tends to occur on days with lower maximum air temperature. Multivariate logistic regression analysis revealed that 3 incidences influence the occurrence of intracerebral hemorrhage (p < 0.01 each): (1) days associated with 4-day periods of mean air pressure in excess of 1,015 hPa; (2) days during which a typhoon was approaching; and (3) days with west or southwest wind . Detailed examination of meteorological data indicates a relationship with the incident rate of ICH.     

Influence of the Selected Antioxidants on the Stability of the Celsior Solution Used for Perfusion and Organ Preservation Purposes

The purpose of the following research was to improve the original Celsior solution in order to obtain a higher degree of stability and effectiveness. The solution was modified by the addition of selected antioxidants such as vitamin C, cysteine, and fumaric acid in the following concentrations: 0.1, 0.3, and 0.5 mmol/l. The solution’s stability was estimated using an accelerated stability test based on changes in histidine concentrations in the solution using Pauly’s method for determining concentrations. Elevated temperatures, the factor accelerating substances’ decomposition reaction rate, were used in the tests. The research was conducted at four temperatures at intervals of 10°C: 60 ± 0.2°C, 70 ± 0.2°C, 80 ± 0.2°C, and 90 ± 0.2°C. It was stated that the studied substances’ decomposition occurred in accordance with the equation for first-order reactions. The function of the logarithmic concentration (log%C) over time was revealed to be rectilinear. This dependence was used to determine the kinetics of decomposition reaction rate parameters (the rate constant of decomposition k, activation energy E _a, and frequency factor A). On the basis of these parameters, the stability of the modified solution was estimated at +5°C. The results obtained show that the proposed antioxidants have a significant effect on lengthening the Celsior solution’s stability. The best results were reached when combining two antioxidants: vitamin C and cysteine in 0.5 mmol/l concentrations. As a result, the Celsior solution’s stability was lengthened from 22 to 299 days, which is 13.5 times. Vitamin C at a concentration of 0.5 mmol/l increased the solution’s stability by 5.2 times (t ₉₀ = 115 days), cysteine at a concentration of 0.5 mmol/l caused a 4.4 times stability increase (t ₉₀ = 96 days), and fumaric acid at a concentration of 0.5 mmol/l extended the stability by 2.1 times (t ₉₀ = 48 days) in relation to the original solution.     

Optical method for monitoring of photodynamic inactivation of bacteria

Photodynamic inactivation is a new promising approach to treat bacterial infections. Usually, the evaluation of the efficacy of this method is done through time-consuming and labor-intensive microbiological test methods. This paper describes the development and implementation of an optical method to evaluate the photodynamic inactivation of bacteria based on non-invasive diffuse reflectance measurements. Five Staphylococcus aureus cultures and 15 mice have been used in this study. A skin lesion was created on the back of all animals, and it was contaminated with S. aureus (5.16 ± 0.013 log CFU/ml). Toluidine Blue O (c = 8.67 × 10 ^− 3 M) has been used as a photosensitiser agent. The bacterial cultures and animals were exposed to laser radiation (λ = 635 nm, P = 15 mW, DE = 8.654 J/cm²) for 20 min. The photodynamic inactivation of bacteria was monitored by acquiring the wounds’ reflection spectra at different time points and by microbiological exams on the bioptical material. The good correlation between the diffuse reflectance and colony-forming units demonstrates the value of this optical method based on diffuse reflectance measurements as a rapid technique to monitor photodynamic bacterial inactivation.     

Electrochemical prevention of marine biofouling on a novel titanium-nitride-coated plate formed by radio-frequency arc spraying

We have developed a new method for forming titanium-nitride(TiN)-coated plates using radio-frequency arc spraying (RFAS). A TiN coating formed by RFAS has been used for electrochemical prevention of marine biofouling. X-ray diffraction and X-ray photoelectron spectroscopy indicate that a TiN composite film containing Ti was formed on a polyethylene terephthalate plate surface when Ti was sprayed by RFAS under atmospheric pressure. A cyclic voltammogram (scan rate 20 mV/s) of the TiN formed by RFAS revealed no oxidative and reductive peak currents in the range −0.6 V to 1.2 V against a saturated silver/silver chloride (Ag/AgCl) electrode. When a potential of 1.0 V against Ag/AgCl was applied to the electrode in seawater, no dissolved Ti was detected. Changes in pH and the chlorine concentration were not observed in this range. In all, only 4.5% of the Vibrio alginolyticus cells attached to the electrode survived when a potential of 0.8 V against Ag/AgCl was applied in seawater for 30 min. In field experiments, attachment of the organisms to the TiN electrode was inhibited by applying an alternating potential of 1.0 V and −0.6 V against Ag/AgCl. The TiN film can be formed by RFAS on large and intricately shaped surfaces, and it is a practical electrode for the electrochemical prevention of fouling of various marine structures. Received: 17 April 1998 / Received revision: 5 June 1998 / Accepted: 19 June 1998     

Effects of weather on the performance of marathon runners

The effects of air temperature, relative and specific humidity, wind speed, solar shortwave radiation, thermal longwave radiation, and rain on the performance of participants in the annual Stockholm Marathon from 1980 to 2008 were analysed statistically. The objective was to validate and extend previous studies by including data on finishing times of slower male and female runners and on the percentage of non-finishers. Due to decadal trends in the finishing time not related to weather, the finishing time anomaly (FTA) was calculated as the deviation of the annual finishing time from the linear trend of the finishing time. In all categories of runners, the single weather parameter with highest correlation with the FTA was the air temperature (correlation coefficient r = 0.66–0.73, with the highest values for slowest runners). Also, the solar shortwave radiation (r = 0.41–0.71), air relative humidity (r = −0.57 to −0.44) and, for male runners, the occurrence of rain (r = −0.51 to −0.42) reached a statistically significant correlation with the FTA, but the effects of the relative humidity and rain only arose from their negative correlation with the air temperature. The percentage of non-finishers (PNF) was significantly affected by the air temperature and specific humidity (r = 0.72 for multiple regression), which is a new result. Compared to faster runners, the results of slower runners were more affected by unfavourable weather conditions; this was previously known for runners with finishing times of 2.1–3 h, and now extended to finishing times of 4.7 h. Effects of warm weather were less evident for female than male runners, which was probably partly due to female runners’ larger ratio of surface area to body mass and slower running speed.     

Solution-Deposited Thin Silver Films on Plastic Surfaces for Low-Cost Applications in Plasmon-Coupled Emission Sensors

We report the deposition of highly uniform thin silver films on plastic materials using a wet-chemistry method, suitable for surface plasmon-coupled emission (SPCE). This approach is reproducible for diverse low-cost applications and versatile to generate silver surfaces on various plastics substrates. An oxygen plasma pretreatment of the plastic provides for rapid silvering, leading to a 47-nm-thick continuous film for SPCE applications. The surface smoothness and thickness of the films have been estimated using atomic force microscope. The higher refractive index of polycarbonate, resulted in an SPCE angle of θ _F = 47⁰ for Rhodamine B, compared to glass (θ _F = 50⁰). The current study presents details on film deposition conditions, appropriate choice of index matching fluids, substrates, and light sources that play a vital role to augment SPCE emission intensity.     

Genetic diversity assessment of sub-samples of cacao, Theobroma cacao L. collections in West Africa using simple sequence repeats marker

Knowledge of genebank and on-farm genetic diversity, particularly in an introduced crop species, is crucial to the management and utilization of the genetic resources available. Microsatellite markers were used to determine genetic diversity in 574 accessions of cacao, Theobroma cacao L., representing eight groups covering parental populations in West Africa, genebank, and farmers’ populations in Nigeria. From the 12 microsatellite markers used, a total of 144 alleles were detected with a mean allelic richness of 4.39 alleles/locus. The largest genetic diversity was found in the Upper Amazon parent population (H _nb  = 0.730), followed by the 1944 Posnette’s Introduction (H _nb  = 0.704), and was lowest in the Local parent population (H _nb  = 0.471). Gene diversity was appreciably high in the farmers’ populations (H _nb  = 0.563–0.624); however, the effective number of alleles was lower than that found in the genebank’s Posnette’s population. Fixation index estimates indicated deficiency of heterozygotes in the Upper Amazon and the Local parent populations (F _is  = 0.209 and 0.160, respectively), and excess of heterozygotes in the Trinitario parent population (F _is  = −0.341). The presence of inbreeding in the Local parent populations and substructure (Wahlund effect) in the Upper Amazon were suggested for the deficiency of heterozygotes observed. Non-significant genetic differentiation observed between the genebank’s and farmers’ populations indicated significant impact of national breeding programs on varieties grown in farmers’ plantations. From this study, we showed that appreciable genetic diversity was present in on-farm and field genebank collections of cacao that can be exploited for crop improvement in West Africa. Suggestions for future conservation of on-farm genetic diversity and local landraces are further discussed.     

Impact of Mapped SSR Markers on the Genetic Diversity of Apricot (<Emphasis Type="Italic">Prunus armeniaca</Emphasis> L.) in Tunisia

The impact of mapped microsatellites on the study of genetic diversity of Tunisian apricot accessions was assessed. The genetic variability of 47 traditional apricot cultivars originating from several areas in Tunisia was investigated with 32 polymorphic microsatellite loci selected for their location throughout the eight linkage groups of Prunus genome. The higher polymorphism and greater transportability of these markers among Prunus species were proved by the expected heterozygosity (He = 0.56) and Shannon’s index of diversity (I = 1.05), indicating that Tunisian apricot germplasm maintained a substantial level of genetic diversity. According to their geographical origin, the genetic differentiation among groups (north, center, and south; Fst = 0.04) was lower, while the gene flow among groups was consequent (Nm = 4.79), attesting a narrow genetic background of apricot in the country. Both unweighted pair-group method with arithmetic mean dendrogram, based on Nei’s genetic distances and factorial correspondence analysis, separated northern cultivars from central and southern cultivars, revealing the same molecular basis of apricot material in the Center and the South of Tunisia. These results revealed the efficiency of mapped markers for genetic variability measurements compared to randomly ones, however, no advantage was observed considering the genetic relationships among studied accessions.     

The influence of nanoscopically thin silver films on bacterial viability and attachment

The physicochemical and bactericidal properties of thin silver films have been analysed. Silver films of 3 and 150 nm thicknesses were fabricated using a magnetron sputtering thin-film deposition system. X-ray photoelectron and energy dispersive X-ray spectroscopy and atomic force microscopy analyses confirmed that the resulting surfaces were homogeneous, and that silver was the most abundant element present on both surfaces, being 45 and 53 at.% on the 3- and 150-nm films, respectively. Inductively coupled plasma time of flight mass spectroscopy (ICP-TOF-MS) was used to measure the concentration of silver ions released from these films. Concentrations of 0.9 and 5.2 ppb were detected for the 3- and 150-nm films, respectively. The surface wettability of the films remained nearly identical for both film thicknesses, displaying a static water contact angle of 95°, while the surface free energy of the 150-nm film was found to be slightly greater than that of the 3-nm film, being 28.8 and 23.9 mN m⁻¹, respectively. The two silver film thicknesses exhibited statistically significant differences in surface topographic profiles on the nanoscopic scale, with R _a, R _q and R _max values of 1.4, 1.8 and 15.4 nm for the 3-nm film and 0.8, 1.2 and 10.7 nm for the 150-nm film over a 5 × 5 μm scanning area. Confocal scanning laser microscopy and scanning electron microscopy revealed that the bactericidal activity of the 3-nm silver film was not significant, whereas the nanoscopically smoother 150-nm silver film exhibited appreciable bactericidal activity towards Pseudomonas aeruginosa ATCC 9027 cells and Staphylococcus aureus CIP 65.8 cells, obtaining up to 75% and 27% sterilisation effect, respectively.     

Assessment of Cu (II)-Bearing Montmorillonite on Cd Adsorption

The abilities of montmorillonite (MMT) and Cu (II)-bearing montmorillonite (Cu-MMT) for adsorption of Cd from aqueous solutions have been studied at different optimized conditions of shaking time, pH value, and initial concentration, respectively. The results showed that the adsorbability of Cu-MMT onto Cd is stronger than the MMT. The amount of Cu-MMT necessary to remove Cd from solution was about 0.5 g for 100–200 mg/L Cd solution at a pH of 4.0. The maximum adsorption (94%) was 20 min of shaking time using Cu-MMT as adsorbent. The maximum adsorption of Cd = 95% at a pH of 4.0. By increasing the initial concentration, the adsorption amount of Cd onto Cu-MMT increased. Animal experiment of this study indicated that the addition of Cu-MMT to the Cd-contaminated diet of pigs reduced significantly the Cd levels in tissues (p < 0.05) and increased contents in feces (p < 0.01), improving the safety of animal products. Thus, the overall results established the use of Cu-MMT as a heavy metal adsorbent in animal’s diets, implying a potential protective role against heavy metal toxicities.     

Estimation of formamide harmonic and anharmonic modes in the Kohn-Sham limit using the polarization consistent basis sets

Formamide harmonic and anharmonic frequencies of fundamental vibrations in the gas phase and in several solvents were successfully estimated in the B3LYP Kohn-Sham complete basis set limit (KS CBS). CBS results were obtained by extrapolating a power function (two-parameter formula) to the results calculated with polarization-consistent basis sets. Anharmonic corrections using the second order perturbation treatment (PT2) and hybrid B3LYP functional combined with polarization consistent pc-n (n = 0, 1, 2, 3, 4) and several Pople’s basis sets were analyzed for all fundamental formamide vibrational modes in the gas phase and solution. Solvent effects were modeled within a PCM method. The anharmonic frequency of diagnostic amide vibration C = O in the gas phase and the CCl₄ solution calculated with the VPT2 method was significantly closer to experimental data than the corresponding harmonic frequency. Both harmonic and anharmonic frequencies of C = O stretching mode decreased linearly with solvent polarity, expressed by relative environment permittivity (ε) ratio (ε − 1)/(2ε + 1). However, an unphysical behavior of solvent dependence of some low frequency anharmonic amide modes of formamide (e.g., CN stretch, NH₂ scissoring, and NH₂ in plane bend) was observed, probably due to the presence of severe anharmonicity and Fermi resonance.     

RETRACTED ARTICLE: Archaeal <Emphasis Type="Italic">amoA</Emphasis> Genes Outnumber Bacterial <Emphasis Type="Italic">amoA</Emphasis> Genes in Municipal Wastewater Treatment Plants in Bangkok

The contribution of ammonia-oxidizing archaea (AOA) to nitrogen removal in wastewater treatment plants (WWTPs) remains unknown. This study investigated the abundance of archaeal (AOA) and bacterial (ammonia-oxidizing bacteria (AOB)) amoA genes in eight of Bangkok’s municipal WWTPs. AOA amoA genes (3.28 × 10⁷ ± 1.74 × 10⁷–2.23 × 10¹¹ ± 1.92 × 10¹¹ copies l⁻¹ sludge) outnumbered AOB amoA genes in most of the WWTPs even though the plants’ treatment processes, influent and effluent characteristics, removal efficiencies, and operation varied. An estimation of the ammonia-oxidizing activity of AOA and AOB suggests that AOA involved in autotrophic ammonia oxidation in the WWTPs. Statistical analysis shows that the numbers of AOA amoA genes correlated negatively to the ammonium levels in effluent wastewater, while no correlation was found between the AOA amoA gene numbers and the oxygen concentrations in aeration tanks. An analysis of the AOB sequences shows that AOB found in the WWTPs limited to only two AOB clusters which exhibit high or moderate affinity to ammonia. In contrast to AOB, AOA sequences of various clusters were retrieved, and they were previously recovered from a variety of environments, such as thermal and marine environments.     

Analysis of callouts made in relation to wild urban marmosets (Callithrix penicillata) and their implications for urban species management

In this study, we investigated what problems urban marmosets (Callithrix penicillata) face in a city environment through the analysis of responses to callouts (N = 348) made by the environmental police of Belo Horizonte, Minas Gerais, Brazil, in the period from 2002 to 2007. Our objective was to characterise the problems faced by the marmosets and human city dwellers. The environmental police responded to two types of callouts: (1) solicitation whereby a person called them to report a problem (N = 218); and (2) the report of a hurt or injured animal (N = 127). On average, one callout per week was made in relation to urban marmosets. We found no time of year effects in relation to callouts, or any effect of gender or age of the person making the callout (P > 0.05). Furthermore, we found no environmental (e.g. percentage of “green area”) or socioeconomical variables (e.g. salary levels) of the city’s administrative regions associated with callouts (P > 0.05). The majority of callouts resulted in the attempt to capture marmosets (N = 345), and usually, only one animal was captured (N = 309). Many of these animals were released into city forest fragments (N = 146). Some sick animals were sent to veterinary clinics (N = 25) whereas others or confiscated animals were sent to the government’s wildlife processing centre (N = 143). From this data, we were able to make a series of recommendation about how the management of urban marmosets could be improved.     

Extrapolation of water and formaldehyde harmonic and anharmonic frequencies to the B3LYP/CBS limit using polarization consistent basis sets

The harmonic and anharmonic frequencies of fundamental vibrations in formaldehyde and water were successfully estimated using the B3LYP Kohn-Sham limit. The results obtained with polarization- and correlation-consistent basis sets were fitted with a two-parameter formula. Anharmonic corrections were obtained by a second order perturbation treatment (PT2). We compared the performance of the PT2 scheme on the two title molecules using SCF, MP2 and DFT (BLYP, B3LYP, PBE and B3PW91 functionals) methods combined with polarization consistent pc-n (n = 0, 1, 2, 3, 4) basis sets, Dunning’s basis sets (aug)-cc-pVXZ where X = D, T, Q, 5, 6 and Pople’s basis sets up to 6-311++G(3df,2pd). The influence of SCF convergence level and density grid size on the root mean square of harmonic and anharmonic frequency deviations from experimental values was tested. The wavenumber of formaldehyde CH₂ anharmonic asymmetric stretching mode is very sensitive to grid size for large basis sets; this effect is not observed for harmonic modes. BLYP-calculated anharmonic frequencies consistently underestimate observed wavenumbers. On the basis of formaldehyde anharmonic frequencies, we show that increasing the Pople basis set size does not always lead to improved agreement between anharmonic frequencies and experimental values.     

Highly efficient plant regeneration and <Emphasis Type="Italic">in vitro</Emphasis> polyploid induction using hypocotyl explants from diploid mulberry (<Emphasis Type="Italic">Morus multicaulis</Emphasis> Poir.)

Efficient plant regeneration is essential for successful transformation and in vitro polyploidy induction in mulberry. A high frequency (80%) of plant regeneration from hypocotyls occurred under in vitro conditions in mulberry (Morus multicaulis Poir.). We identified three key factors for enhancing successful regeneration based on earlier work: (1) hypocotyl position, (2) the combination and concentration of growth regulators, and (3) the addition of AgNO₃. The highest frequency of shoot regeneration was achieved using hypocotyl segments, which are proximal to apical meristems, and the optimal culture conditions were Murashige and Skoog’s (MS) (Murashige and Skoog, 1962) basal medium supplemented with 3.0 mg l⁻¹ 6-benzylamino purine, 0.3 mg l⁻¹ indole-3-acetic acid, 0.1% polyvinypyrrolidone, and 1.0 mg/l silver nitrate (AgNO₃) under subdued light at 25 ± 2°C. Treating the shoots with 0.2% colchicine (dipping for 72 h) resulted in a 14% tetraploid frequency, whereas a 20% tetraploid frequency resulted from using a 0.25% colchicine (dripping for 5 d) treatment, as determined by chromosome number counts. The diploid plant chromosome number was 28 (2n = 2x = 28) and that of tetraploid plants was 56 (2n = 4x = 56). Regenerated shoots rooted easily in 8–10 d using half-strength basal MS medium with 0.5 mg l⁻¹ indole-3-butyric acid and were successfully established in the soil.     

Trail Marking and Abandonment of Depleted Feeding Sites by the Caterpillars of <Emphasis Type="Italic">Eutachyptera psidii</Emphasis> (Lepidoptera: Lasiocampidae)

The caterpillars of Eutachytptera psidii (Lepidoptera: Lasiocampidae) mark trails between their nest and distant feeding sites with a trail pheromone secreted from the ventral surfaces of their last abdominal segments. The threshold sensitivity to artificial trails prepared from an hexane extract of the pheromone was 0.75 × 10⁻³ caterpillar-equivalents per cm of trail. In tests of trail-specificity involving four other social species, the caterpillars responded only to trails prepared from a pheromone extract of the closely related genus Gloveria. Tests were conducted to determine the efficiency with which colonies abandon exhausted feeding sites in favor of new food finds. On their first forays after their food sources were experimentally moved from established feeding sites to new sites, 67.5 ± 3.6% of all the evening’s activity occurred on pathways leading to the previously established sites. During their next two forays, 86.3 ± 3.7% and 92.1 ± 2.0% of all activity occurred on pathways leading to the new sites. Efficient abandonment of exhausted feeding sites is attributed to the persistence of the trail pheromone, differential marking of new and old pathways and to the caterpillar’s ability to discern trail strength and to choose stronger over weaker trails at choice points.     

Effect of Different Iodine Nutrition on Cerebellum Pcp-2 in Rat Offspring During Lactation

The thyroid functions of breastfed infants, as well as (indirectly) the development of their central nervous system, are dependent on the iodine status of the lactating mother. Purkinje cell protein-2 is a cell-specific marker of the cerebellum Purkinje cell and is a suitable indicator for observing the postnatal development of the cerebellum after birth. We measured the Purkinje cell protein-2 mRNA and protein levels in the rat cerebellum in the critical postnatal (14 days after birth) and maturation periods (28 days after birth) to determine the effect of different nutritional iodine levels on cerebellum growth in the offspring during lactation. We found that severe iodine deficiency resulted in thyroid dysfunction in lactating rats and their offspring on both 14 and 28 days, showing maternal total T₄ 16.7 ± 12.0 vs 36.4 ± 15.0, P < 0.05 (14 days) and 22.6 ± 18.7 vs 53.4 ± 9.4, P < 0.01 (28 days), and neonatal total T₄ 10.6 ± 2.3 vs 16.4 ± 4.7, P < 0.01(14 days) and 12.8 ± 2.9 vs 16.7 ± 3.4, P < 0.05 (28 days), respectively. The Purkinje cell protein-2 mRNA and its protein levels in offspring rats were significantly reduced that showed Purkinje cell protein-2 mRNA 1.12 ± 0.04 vs 2.25 ± 0.53, P < 0.05 (14 days) and 1.74 ± 0.94 vs 8.69 ± 2.71, P < 0.01 (28 days). However, mild iodine deficiency and excessive iodine maintained almost normal thyroid function in maternal and neonatal rats and normal Purkinje cell protein-2 mRNA and protein levels in offspring’s cerebellum. We conclude that severe iodine deficiency could significantly reduce Purkinje cell protein-2 mRNA and its protein levels, indicating that the cerebellum development was retarded, but mild iodine deficiency and excessive iodine could maintain them at an approximately normal level by the mother’s and offspring’s compensations, especially by the mother’s mammary glands.     

Mitochondrial DNA reveals low population differentiation in elongate loach, <Emphasis Type="Italic">Leptobotia elongata</Emphasis> (Bleeker): implications for conservation

Elongate loach (Leptobotia elongata (Bleeker)), an endemic fish species to China, is a famous ornamental freshwater fish. Here, a comparative study of mtDNA control region (D-loop) (835 bp) sequences was performed to analyze its wild population structure and evaluate the genetic diversity for 110 individuals from five locations in the upper reaches of the Yangtze River, China. A total of 49 polymorphic sites and 45 haplotypes yielded high haplotype diversity (h = 0.952), but low nucleotide diversity (π = 0.00454) as that of many fish species. Sequence divergences between haplotypes ranged from 0.0033 ± 0.0011 to 0.0050 ± 0.0012 in intra-groups, and from 0.0037 ± 0.0.0011 to 0.0050 ± 0.0012 between groups. Significant values of Tajima’s D (−1.86383, P < 0.01) and Fu’s F _S (−25.93, P < 0.01), together with uni-modal mismatch distribution, indicated a recent genetic bottleneck or population expansion of the species. Analysis of molecular variance (AMOVA) indicated a small amount of differentiation among groups (1.7%); most of the total variation occurred within groups (98.3%). Also, there was no significant population structure (F _ST = 0.017, P > 0.05), and estimates of gene flows among groups were extremely high (Nm = 28.88), suggesting low genetic divergence between populations in the species. The lack of genetic differentiation among groups is most likely due to the combined gene flow from the downstream movement of eggs and larvae with currents and the upstream or downstream migration of adults throughout the distribution. These groups of L. elongata distributed in upper reaches of the Yangtze River should be considered as a single management unit.     

Molecular modeling studies of poly lactic acid initiation mechanisms

The two possible routes to synthesize poly (lactic acid) are polycondensation of the lactic acid and ring opening polymerization (ROP) of the lactide. This work involves molecular modeling of the polymerization initiation mechanisms using different initiators a) H₂SO₄ for polycondensation b) aluminum isopropoxide for coordination-insertion ROP c)methyl triflate for cationic ROP, and d) potassium methoxide for anionic ROP. For molecular modeling of PLA, we have benchmarked our approach using Ryner’s work on ROP of L-lactide using stannous (II) 2-ethylhexanoate (Sn(Oct)₂) and methanol as initiators. Our values of -15.2 kcal mol^-1 and -14.1 kcal mol^-1 for enthalpy changes in the two steps of activated complex formation match with Ryner’s. Geometric and frequency optimizations have been done on Gaussian’03 using B3LYP density functional theory along with the basis sets LANL2DZ for metal atoms and 6–31G* and 6–31G** for non metal atoms. The kinetic rate constant for each mechanism has been calculated using the values of energy of activation, change in enthalpy, Gibbs free energy, entropy and the partition functions from the Gaussian’03 output. Our polycondensation rate constant value of 1.07 × 10^–4 se^-1 compares well with 1.51 × 10^–4 se^-1 as reported by Wang. However, ROP rate constants could not be validated due to lack of experimental data. Figure Cationic Ring Opening Polymerization of L-Lactide

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Zinc,Manganese, Calcium,Copper, and Cadmium Level in Scalp Hair Samples of Schizophrenic Patients

The purpose of the study was to determine the concentration of trace elements present in scalp hair sample of schizophrenic patients and to find out the relationship between trace elements level and nutritional status or socioeconomic factors. The study was conducted among 30 schizophrenic male patients and 30 healthy male volunteers. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Hair trace element concentrations were determined by flame atomic absorption spectroscopy and analyzed by independent t test, Pearson’s correlation analysis, regression analysis, and analysis of variance (ANOVA). Mn, Zn, Ca, Cu, and Cd concentrations of schizophrenic patients were 3.8 ± 2.31 μg/gm, 171.6 ± 59.04 μg/gm, 396.23 ± 157.83 μg/gm, 15.40 ± 5.68 μg/gm, and 1.14 ± 0.89 μg/gm of hair sample, while those of control subjects were 4.4 ± 2.32 μg/gm, 199.16 ± 27.85 μg/gm, 620.9 ± 181.55 μg/gm, 12.23 ± 4.56 μg/gm, and 0.47 ± 0.32 μg/gm of hair sample, respectively. The hair concentration of Zn and Ca decreased significantly (p = 0.024; p = 0.000, respectively) and the concentration of Cu and Cd increased significantly (p = 0.021; p = 0.000, respectively) in schizophrenic patients while the concentration of Mn (p = 0.321) remain unchanged. Socioeconomic data reveals that most of the patients were poor, middle-aged and divorced. Mean body mass indices (BMIs) of the control group (22.26 ± 1.91 kg/m²) and the patient group (20.42 ± 3.16 kg/m²) were within the normal range (18.5−25.0 kg/m²). Pearson’s correlation analysis suggested that only Ca concentration of patients had a significant positive correlation with the BMI (r = 0.597; p = 0.000) which was further justified from the regression analysis (R ² = 44%; t = 3.59; p = 0.002) and one-way ANOVA test (F = 3.62; p = 0.015). A significant decrease in the hair concentration of Zn and Ca as well as a significant increase in the hair concentration of Cu and Cd in schizophrenic patients than that of its control group was observed which may provide prognostic tool for the diagnosis and treatment of this disease. However, further work with larger population is suggested to examine the exact correlation between trace element level and the degree of disorder.