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Neuropsychological investigations can help untangle the aetiological and phenomenological heterogeneity of schizophrenia but have scarcely been employed in the context of treatment-resistant (TR) schizophrenia. No population-based study has examined neuropsychological function in the first-episode of TR psychosis.
We report baseline neuropsychological findings from a longitudinal, population-based study of first-episode psychosis, which followed up cases from index admission to 10 years. At the 10-year follow up patients were classified as treatment responsive or TR after reconstructing their entire case histories. Of 145 cases with neuropsychological data at baseline, 113 were classified as treatment responsive, and 32 as TR at the 10-year follow-up.
Compared with 257 community controls, both case groups showed baseline deficits in three composite neuropsychological scores, derived from principal component analysis: verbal intelligence and fluency, visuospatial ability and executive function, and verbal memory and learning (p values⩽0.001). Compared with treatment responders, TR cases showed deficits in verbal intelligence and fluency, both in the extended psychosis sample (t = −2.32; p = 0.022) and in the schizophrenia diagnostic subgroup (t = −2.49; p = 0.017). Similar relative deficits in the TR cases emerged in sub-/sensitivity analyses excluding patients with delayed-onset treatment resistance (p values<0.01–0.001) and those born outside the UK (p values<0.05).
Verbal intelligence and fluency are impaired in patients with TR psychosis compared with those who respond to treatment. This differential is already detectable – at a group level – at the first illness episode, supporting the conceptualisation of TR psychosis as a severe, pathogenically distinct variant, embedded in aberrant neurodevelopmental processes.
Population of high quantum number states can differ from their LTE values at high densities (Ne ~106 − 108 cm−3) and temperatures of the order of 104 K. In this case, the intensity of recombination lines can be strongly amplified. The amount of amplification depends on density and temperature, and it is different for different quantum numbers, allowing the determination of the physical and kinematic conditions of the emitting region through the observation of recombination lines of different quantum numbers. This was the case of the massive binary system η Carinae. This system was observed with ALMA in the recombination lines H21α, H28α, H30α, H40α and H42α and the continuum at the frequencies of the corresponding lines. The continuum spectrum was characteristic of a compact HII region, becoming optically thin at around 300 GHz. From the intensity and width of the recombination lines we concluded that the not-resolved emission region, assumed spherically symmetric, is a shell of 40 AU radius and 4 AU width, expanding at velocities between 20 and 60 km s−1, with density of 107 cm−3 and temperature of 17000 K.
Since the very beginning of the Itapetinga 45-ft antenna operations in 1971, there were plans to use it as a southern hemisphere VLBI terminal for high north-south resolution. The first successful VLBI tests were performed on water vapor lines in cooperation with Haystack Observatory in 1978 in one of the last runs using the MkI system. This cooperation led to the construction of a MkII terminal for Itapetinga years later (1981–1983). Astrophysical VLBI runs have been carried out since 1984, with the cooperation of Caltech, producing maps of unique resolution on stronger quasars, especially on 3C273 whose evolution has been followed since then. Recently, Bonn joined the collaboration in astrophysical VLBI programs. Itapetinga also participated successfully in geodetic surveys, and in the Vega-Venus mission, in collaboration with JPL and French organizations CNES, Observatoire de Paris and IGN. Plans for continuation and expansion of the Itapetinga VLBI participation in international efforts depend strongly on support to maintain and upgrade instrumentation at the Brazilian Radio Observatory.
Deciphering the relative importance of genetic and environmental factors, which play a major role in the prevalence of early childhood caries (ECC), can help clinicians with planning a long-term preventive treatment. The objective of the study was to determine the prevalence and heritability of ECC among monozygotic (MZ) and dizygotic (DZ) twins in Chennai, India, in the year 2013. A cross-sectional study was designed to estimate the prevalence of ECC among twins. Zygosity classification for the survey framework was adapted from a highly accurate parental report questionnaire pertaining to the physical similarity between twins. The associated heritability index was estimated. The Decayed, Missing, Filled Surface (DMFS) Index was used as the diagnostic criterion for dental caries. The prevalence of ECC was estimated at 18.7%. The correlation coefficient between the twin pair showed significant correlation. The heritability index for ECC was estimated at 15% higher prevalence of ECC found among children in the age group 25–36 months. The heritability estimate indicated a relatively low genetic influence for early childhood caries among twins. There was no significant difference detected in the concordance rate for the MZ and DZ twins. Further research could be directed toward the prevalence of ECC among higher age group children to explore the role of genetic and environmental factors.
Silicon is emerging as a very attractive anode material for lithium ion batteries due to its low discharge potential, natural abundance, and high theoretical capacity of 4200 mAh/g, more than ten times that of graphite (372 mAh/g). This high charge capacity is the result of silicon’s ability to incorporate 4.4 lithium atoms per silicon atom; however, the incorporation of lithium also leads to a 300-400% volume expansion during charging, which can cause pulverization of the material and loss of access to the silicon. The architecture of the anode must therefore be able to adapt to this volume increase. Here we present a layered carbon nanotube and silicon nanoparticle electrode structure, fabricated using directed assembly techniques. The porous carbon nanotube layers maintain electrical connectivity through the active material and increase the surface area of the current collector. Using this architecture, we obtain an initial capacity in excess of 4000 mAh/g, as well as increased power and energy density as compared to anodes fabricated using the standard procedure of slurry casting.
Increased dietary Na intake and decreased dietary K intake are associated with higher blood pressure. It is not known whether the dietary Na:K ratio is associated with all-cause mortality or stroke incidence and whether this relationship varies according to race. Between 2003 and 2007, the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort enrolled 30 239 black and white Americans aged 45 years or older. Diet was assessed using the Block 98 FFQ and was available on 21 374 participants. The Na:K ratio was modelled in race- and sex-specific quintiles for all analyses, with the lowest quintile (Q1) as the reference group. Data on other covariates were collected using both an in-home assessment and telephone interviews. We identified 1779 deaths and 363 strokes over a mean of 4·9 years. We used Cox proportional hazards models to obtain multivariable-adjusted hazard ratios (HR). In the highest quintile (Q5), a high Na:K ratio was associated with all-cause mortality (Q5 v. Q1 for whites: HR 1·22; 95 % CI 1·00, 1·47, P for trend = 0·084; for blacks: HR 1·36; 95 % CI 1·04, 1·77, P for trend = 0·028). A high Na:K ratio was not significantly associated with stroke in whites (HR 1·29; 95 % CI 0·88, 1·90) or blacks (HR 1·39; 95 % CI 0·78, 2·48), partly because of the low number of stroke events. In the REGARDS study, a high Na:K ratio was associated with all-cause mortality and there was a suggestive association between the Na:K ratio and stroke. These data support the policies targeted at reduction of Na from the food supply and recommendations to increase K intake.
The use of nonallergic, nontoxic, and eco-friendly natural dyes has become a matter of significant importance due to increased environmental awareness on the need to avoid hazardous synthetic dyes. This study was to determine the staining properties of the dye extract of Lonchocarpus cyanescens on histomorphology of the testis. Freshly cut leaves of L. cyanescens obtained from Akpan Ifia Inan village in Ikono local government area of Akwa Ibom state (latitude 5° 10′ 12″ N; longitude 7° 48′ 0″ E) were put into a plastic jar and boiling water was poured to cover the leaves. It was covered and left for an hour. The liquid was strained and potassium hydroxide was added to the dye water mixture to reach a pH of 9. A whisk was used to mix air into the liquid, and the mixuture was then allowed to sit until the blue indigo had settled to the bottom of the container. The dye was diluted with 70% ethanol to a concentration of 0.1 g/mL and was used to stain sections of testes. Its potential for use as a counterstain was also investigated. The testes sections were stained in shades of blue. The dye overshadowed the colors of haematoxylin and eosin. Preliminary phytochemical screening of L. cyanescens revealed that it contains alkaloids, saponins, flavonoids, and tannins.
In the beginning of the second millennium B.C. Babylon became the centre of power in Mesopotamia. Hammurapi (1792-1750 B.C.) was one of the most important kings of the First Dynasty of Babylon. He is above all known for his law code (Codex Hammurapi). At the height of his power the Old Babylonian Empire extended as far as Sumer in the south and to Nineveh in the north. After the Old Babylonian times a dark period followed in the history of Mesopotamia. The conquest of Babylon in 1595 B.C. by the Hittite king Mursilis I ended the First Dynasty of Babylon. His allies, the Kassites from the Zagros Mountains, occupied Babylon without breaking the Babylonian traditions. Dur Kurigalzu became their capital. In 1157 B.C. the Kassite Dynasty was attacked from Elam (southwestern Iran) and came to an end.
Recent work has been done on the analysis of elastic stress singularities, such as cracks and dislocations, which propagate at supersonic speeds. Gumbsch and Gao have performed atomistic simulations in which dislocations are created and travel at transonic velocities (speeds which are greater than the material's shear wave speeds but less than the longitudinal wave speed) close to the theoretical value corresponding to the radiation-free state for glide motion. Gao et al. have derived expressions for this radiation-free velocity in both isotropic and anisotropic media. We have performed molecular dynamics simulations showing dislocation nucleation at crystal surface ledges. Dislocations were nucleated at either sub- or transonic velocities, depending upon the ambient temperature, and accelerated to transonic speeds. This paper shows the velocity profiles for the emitted dislocations and compares velocities observed with a theoretical minimum-radiation speed derived by a Strohtype anisotropic elasticity analysis performed by Barnett and Zimmerman. Our findings are particularly exciting considering these simulations were not specifically engineered for the purpose of creating transonic defects, but show agreement with theory nonetheless.
We have simulated the dynamical failure of three-dimensional notched solids under tension using molecular dynamics and up to 100 million atoms. We discovered a dynamical brittle-to-ductile transition in the rapid cleavage of rare-gas solids when the crack velocity approaches one-third of the Rayleigh sound speed. At this transition, the crack tip has already begun to roughen on the atomic scale. This suggests that the brittle crack undergoes a dynamic instability which immediately leads to the initiation of plastic failure by the spontaneous emission and proliferation of dislocations and crack arrest.
The objective of this study was to highlight the usefulness of micron-sized Li4Ti5O12 in three distinctive areas: a) cathode of a low-voltage Li battery, b) insertion type auxiliary electrode to investigate the electrochemistry of oxide cathode materials, and c) anode of a Li-ion cell in conjunction with LiMn2O4 cubic spinel cathode. Li cells with Li4Ti5O12 exhibited an open circuit voltage of ∼1.6V, >90% utilization (in terms of the theoretical capacity) at ∼C/10 rate, ∼40% utilization 5C rate, and extended full-depth charge/discharge cycling at ≥ 1C rates with virtually no capacity fade. LiMn2O4 cathodes, evaluated in Li(4+xTi5O12 (x = ∼1.2)/LiMn2O4 cells, exhibited extended full-depth cycling capability with a small capacity fade rate of <0.1% which appeared to slow down with cycling. At a 1C discharge rate, over 190 cycles were demonstrated corresponding to an end utilization of ∼90 mAh/g or ∼0.6 mole Li per LiMn204. Balanced Li4Ti5O12//solid polymer electrolyte//LiMn2O4 full cells of slightly cathode-limited configuration had an open-circuit voltage of ∼3.0V and a mid-discharge voltage of ∼2.5V showing full-depth extended cycling capability at a utilization of ∼90 mAh/g or ∼0.6 mole Li per LiMn204 at the 1C and ∼0.45 mole Li per LiMn2O4 at the 7.5C discharge rate.
The preparation of poly(ρ-phenylene vinylene) (PPV) encapsulated in a mesoporous silica, MCM-41, is reported. In situ polymerization of xylylene bis(tetrahydrothiophenium chloride) yields a highly luminescent, yellow powder with a fluorescence spectrum matching that of unencapsulated PPV. Nitrogen adsorption isotherms show that the pore size of the PPVloaded MCM-41 is significantly smaller than that of empty MCM-41 and a polymer loading of ca. 8% by weight is obtained by thermogravimetric analysis. Photoluminescence data for the encapsulated PPV are presented.
In this paper we describe the fabrication of oxide based devices similar in architecture to a conventional FET with source, drain, and gate electrodes and a channel. This distinctive characteristic of our device is the use of a channel material capable of undergoing a field-induced Mott insulator-metal transition at room temperature. Lithographic techniques developed for oxide materials have been combined with pulsed laser deposition of perovskite materials onto single-crystal strontium titanate (STO) substrates to fabricate these devices. Materials chosen for the Mott transition channel include La2CuO4 (LCO) and YBCO, p-type; and Nd2CuO4, n-type.
The preparation of poly(p-phenylene vinylene) (PPV) encapsulated in a mesoporous silica, MCM-41, is reported. In situ polymerization of xylylene bis(tetrahydrothiophenium chloride) yields a highly luminescent, yellow powder with a fluorescence spectrum matching that of unencapsulated PPV. Nitrogen adsorption isotherms show that the pore size of the PPV- loaded MCM-41 is significantly smaller than that of empty MCM-41 and a polymer loading of ca. 8% by weight is obtained by thermogravimetric analysis. Photoluminescence data for the encapsulated PPV are presented.
The optimum conditions for preparing LiNiO2 with good electrochemical performance are presented. Three different methods were investigated:
• LiOH and NiO at700°C in air(Batch A),
• LiOH and NiO between 150 and 750 °C in oxygen (Batch B), and
• LiNO3 and NiCO3 between 600 and 750 °C in oxygen (Batch C).
Batch C exhibited the highest first discharge capacity of about 150 mAh/g between 2.0 and 4.0V with a solid state Li/LiNiO2 cell containing a PAN-based polymer electrolyte. Solid state carbon/LiNiO2 cells and two-cell bipolar batteries demonstrated high rate capabilities at room temperature with an ability to sustain pulsed discharge currents as high as 50 mA/cm2. About 22 500,13 000, and 1000 pulses were obtained at current densities of 10, 20, and 50 mA/cm2, respectively, with a 10 ms pulse width followed by a 50 ms interpulse rest period.
To identify the various oxalates and oxalato-nitrates likely to form during the nuclear fuel reprocessing we study crystallization of such compounds by various methods (slow diffusion, hydrothermal syntheses, in situ oxalate syntheses …), in different conditions and in presence of monovalent ions. In a first stage, lanthanides are used as surrogates of the actinides (III) radioactive elements. This communication reviews various lanthanides (III) compounds obtained by crystallization from nitric acid solution containing hydrazinium ions. Diethyl oxalate was used as a precursor for oxalate ions. A careful adjustment of the experimental conditions allowed us to synthesize single crystals of nitrates, oxalato-nitrates and oxalates with various ligand/Ln(III) ratio and containing nitrates as ligands or as counter ions. In all the compounds hydrazinium ions are present as counter ions. The crystal growth method is described and the crystal structures, determined by X-ray diffraction from single crystals, are discussed in terms of metal-oxalate frameworks.