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Biomass carbon-based materials are highly promising for supercapacitor (SC) electrodes due to their availability, environment-friendliness, and low cost. Herein, an easy energy-saving hydrothermal process was used to produce NiCo2O4/NiOOH (NiCoO) composites with biomass carbon (BC) derived from the bark of Anacardium occidentale (AO) at different synthesis time durations (2 h, 4 h, 8 h, 16 h). The structural and morphological properties of the samples were analysed using XRD, Raman spectroscopy, XPS, SEM, TEM and BET, and the results exhibit the presence of carbon inserted into the nickel-cobalt hydroxide matrix. The NiCoO@BC composite synthesized in 4 h (NiCoO@BC(4 h)) displays a good specific capacitance of 475 F g-1 at 0.5 A g-1 and a low equivalent series resistance (ESR) value of 0.36 Ω. It shows a good coulombic efficiency of 98% and retains 86% of the capacitance after 4000 cycles. The asymmetric supercapacitor (ASC) device (NiCoO@BC(4 h)//AC) assembled using activated carbon (AC) as a negative electrode displays 20 W h kg-1 energy density and 900 W kg-1 power density at 1 A g-1. The stability test shows a good coulombic efficiency of 99% and 78% capacitance retention after 15 000 cycles. These findings imply that NiCoO@BC composites have outstanding electrochemical properties, making them suitable as SC electrode materials.

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Biomass-waste activated carbon/molybdenum oxide/molybdenum carbide ternary composites are prepared using a facile in-situ pyrolysis process in argon ambient with varying mass ratios of ammonium molybdate tetrahydrate to porous peanut shell activated carbon (PAC). The formation of MoO2 and Mo2C nanostructures embedded in the porous carbon framework is confirmed by extensive structural characterization and elemental mapping analysis. The best composite when used as electrodes in a symmetric supercapacitor (PAC/MoO2/Mo2C-1//PAC/MoO2/Mo2C-1) exhibited a good cell capacitance of 115 F g-1 with an associated high specific energy of 51.8 W h kg-1, as well as a specific power of 0.9 kW kg-1 at a cell voltage of 1.8 V at 1 A g-1. Increasing the specific current to 20 A g-1 still showcased a device capable of delivering up to 30 W h kg-1 specific energy and 18 kW kg-1 of specific power. Additionally, with a great cycling stability, a 99.8% coulombic efficiency and capacitance retention of ~83% were recorded for over 25,000 galvanostatic charge-discharge cycles at 10 A g-1. The voltage holding test after a 160 h floating time resulted in increase of the specific capacitance from 74.7 to 90 F g-1 at 10 A g-1 for this storage device. The remarkable electrochemical performance is based on the synergistic effect of metal oxide/metal carbide (MoO2/Mo2C) with the interconnected porous carbon. The PAC/MoO2/Mo2C ternary composites highlight promising Mo-based electrode materials suitable for high-performance energy storage. Explicitly, this work also demonstrates a simple and sustainable approach to enhance the electrochemical performance of porous carbon materials.

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Nitrogen (N) doping of porous carbon materials is an effective strategy for enhancing the electrochemical performance of electrode materials. Herein, we report on ex-situ (post) nitrogen-doped porous carbons prepared using a biomass waste, peanut shell (PS) as a carbon source and melamine as the nitrogen source. The synthesis method involved a two-step mechanism, initial chemical activation of the PS using KOH and post N-doping of the activated carbon. The effect of the activating agent/precursor ratio and the ex-situ N-doping on the structural, textural, electrochemical properties of the porous carbons was studied. The ex-situ N-doped porous carbon with an optimum amount of KOH to PS exhibited the best capacitance performance with a specific surface area (SSA) of 1442 m2 g-1 and an enriched nitrogen content (3.2 at %). The fabricated symmetric device exhibited a 251.2 F g-1 specific capacitance per electrode at a gravimetric current of 1 A g-1 in aqueous electrolyte (2.5 M KNO3) at a wide cell voltage of 2.0 V. A specific energy of 35 Wh kg-1 with a corresponding specific power of 1 kW kg-1 at 1 A g-1 was delivered with the device still retaining up to 22 Wh kg-1 and a 20 kW kg-1 specific power even at 20 A g-1. Moreover, long term device stability was exhibited with an 83.2% capacity retention over 20 000 charge/discharge cycles and also a good rate capability after 180 h of floating at 5 A g-1. This great performance of the symmetric supercapacitor can be correlated to the surface porosity and post nitrogen-doping effect which increased the electrochemically-active sites resulting in a remarkable charge storage capability.

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In this work, porous carbon-vanadium oxynitride (C-V2NO) nanostructures were obtained at different nitridation temperature of 700, 800 and 900 °C using a thermal decomposition process. The X-ray diffraction (XRD) pattern of all the nanomaterials showed a C-V2NO single-phase cubic structure. The C-V2NO obtained at 700 °C had a low surface area (91.6 m2 g-1), a moderate degree of graphitization, and a broader pore size distribution. The C-V2NO obtained at 800 °C displayed an interconnected network with higher surface area (121.6 m2 g-1) and a narrower pore size distribution. In contrast, at 900 °C, the C-V2NO displayed a disintegrated network and a decrease in the surface area (113 m2 g-1). All the synthesized C-V2NO yielded mesoporous oxynitride nanostructures which were evaluated in three-electrode configuration using 6 M KOH aqueous electrolyte as a function of temperature. The C-V2NO@800 °C electrode gave the highest electrochemical performance as compared to its counterparts due to its superior properties. These results indicate that the nitridation temperature not only influences the morphology, structure and surface area of the C-V2NO but also their electrochemical performance. Additionally, a symmetric device fabricated from the C-V2NO@800 °C displayed specific energy and power of 38 W h kg-1 and 764 W kg-1, respectively, at 1 A g-1 in a wide operating voltage of 1.8 V. In terms of stability, it achieved 84.7% as capacity retention up to 10,000 cycles which was confirmed through the floating/aging measurement for up to 100 h at 10 A g-1. This symmetric capacitor is promising for practical applications due to the rapid and easy preparation of the carbon-vanadium oxynitride materials.

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The electrochemical performance of hydrothermal synthesized three dimensional (3D) orthorhombic vanadium pentoxide (V2O5) nanosheets and vanadium pentoxide/graphene foam (V2O5/GF) composites at different mass loading of GF were successfully studied. The optimized V2O5/GF-150 mg composite provided a high specific capacity of 73 mA h g-1, which was much higher than that the pristine V2O5 (60 mA h g-1) nanosheets at a specific current of 1 A g-1. A hybrid capacitor was also fabricated by adopting a carbon-based negative electrode obtained from the pyrolysis of an iron-PANI polymer (C-Fe/PANI) mixture and the 3D V2O5/GF-150 mg composite as the positive electrode in 6 M KOH electrolyte. The hybrid device of V2O5/GF-150 mg//C-Fe/PANI demonstrated a high energy density of 39 W h kg-1 with a corresponding high power density of 947 W kg-1 at a specific current of 1 A g-1 in an operating voltage window of 0.0-1.6 V. The hybrid device also exhibited an excellent cycling stability with 74% capacity retention recorded for up to 10,000 constant charging-discharge cycles and an excellent ageing test at a specific current of 10 A g-1.

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Concentration and optical characteristics of dissolved organic matter were studied in rainwater in the urban/coastal city of Thessaloniki, Northern Greece for 2-yr sampling period (2014-2016). The concentration of DOC ranged from 0.33-24.5mg/L with higher values measured in spring-summer period. Higher aromaticity and fluorescence intensity was observed in winter. Chromophoric organic matter represents a significant fraction of DOC that is highly correlated with fluorescence during cold period. Three factor spectral profiles of fluorescence were elucidated, with peaks at protein-like and humic-like area at different intensities. Fluorophores at shorter wavelengths are more susceptible to changes. DOC showed negative relationship with precipitation height, particularly during autumn and spring suggesting washout effect. NMR spectra showed the dominance of aliphatic protons in rainwater. Levoglucosan, sucrose and arabitol were determined in rainwater at concentrations <0.07-2.2µg/L, <0.03-5.1µg/L and <0.03-2.1µg/L, respectively showing impact of biomass combustion and biogenic emissions.

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This study investigates the occurrence of carbonyl compounds in rainwater at the city of Thessaloniki, Northern Greece. The concentrations of carbonyl compounds (as sum of 14 compounds) ranged from 21.8 to 592 µg/L, mean concentration 119 µg/L. Formaldehyde, acetaldehyde, hexanal, glyoxal, and methylglyoxal were the dominant compounds. DOC concentrations in rainwater ranged from 0.46 to 21.3 mg/L. UV-Vis and fluorescence spectra characteristics showed variation among rain events. Carbonyl compounds were negatively correlated with temperature exhibited relatively higher concentrations in cold season. They also influenced by storm origin with higher concentrations under terrestrial air masses. Calm conditions enhance the concentrations of DOC. Wash out is an effective removal mechanism of DOC.

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As field strength increases, the magnetic resonance imaging contrast parameters like relaxation times, magnetization transfer or image phase change, causing variations in contrast and signal-to-noise ratio. To obtain reliable data for these parameters at 16.4 T, high-resolution measurements of the relaxation times T(1), T(2) and T(2)*, as well as of the magnetization transfer ratio and the local frequency in the rat brain were performed. Tissue-specific values were obtained for up to 17 brain structures to assess image contrast. The measured parameters were compared to those found at different field strengths to estimate contrast and signal behavior at increasing field. T(1) values were relatively long with (2272 ± 113) ms in cortex and (2073 ± 97) ms in white matter, but did not show a tendency to converge, leading to an almost linear increase in signal-to-noise ratio and still growing contrast-to-noise ratio. T(2) was short with (25 ± 2) ms in cortex and (20 ± 1) ms in white matter. Magnetization transfer effects increase by around 25% compared to published 4.7 T data, which leads to improved contrast. The image phase, as novel and high-field specific contrast mechanism, is shown to obtain good contrast in deep brain regions with increasing signal-to-noise ratio up to high field strengths.

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The cultivated riverine wetland region Spreewald faces detrimental changes in the hydrological conditions due to a significant discharge reduction. With its dense network of impounded waterways and a forced tendency of sedimentation of soluble reactive phosphorus adsorbed to large amounts of FeOH/FeOOH available from mining water and groundwater discharges the 320 km2 region is favoured to accumulate large amounts of total phosphorus (TR) and thus act as an effective phosphorus sink. The change of conditions strongly challenges this function hereafter. This is especially important because eutrophication of lakes downstream the Spreewald region is controlled by phosphorus. Phosphorus balances at a testfield situated in a polder area typical for the central Spreewald region point out that hydrological and consequently hydraulic conditions are the key factors for the phosphorus sink or source behaviour. This is true for the main processes determine P retention and release at the sediment-surface water transition zone as well as for the dominant phosphorus release and retention pathways: groundwater emissions and sedimentation. In the context of hydrological changes in the Spree river catchment results from point scale and river reach scale point out the need for an adapted water management in the Spreewald region to prevent risk of extended eutrophication tendencies downstream due to forced SRP emissions.

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We investigated whether a preference by patients regarding the gender of a health care provider to manage erectile dysfunction (ED) may be a factor in the diagnosis and care of this condition, whose broader medical significance is an area of increasing interest. A brief questionnaire was completed by 1087 adult males in a primary care setting. The questionnaire explored provider gender preference and other possible biases. The prevalence of ED in the 40-69 age group in our population was 68.8%. The prevalence was 81% in the age group of 70 and more. Of those who reported having experienced ED, 51.5% had discussed it with a provider, and 28.1% had been treated. Approximately, 57% expressed no provider gender preference, regardless of history of ED. Of those who stated a preference, approximately 75% prefer male providers. However, also among those who state a preference, Hispanics are not as likely as non-Hispanics to prefer a male provider (P=0.03). Most believe that males and females are equally qualified to manage ED, but among those who have a different opinion, the gender perceived more favorably is male. The issue of privacy during the discussion of ED was also very important to the respondents in this study.

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The ways in which institutional factors and psychological characteristics of residents interact to determine the behavioral effects of institutionalization were investigated. Two large and five small institutions were rated on resident management practices, aide attitudes, and demographic variables, such as size and cost per resident. Resident variables included preinstitutional deprivation, CA, MA, IQ, and length of institutionalization. The institution and resident variables were used in an attempt to predict three aspects of behavior: responsiveness to social reinforcement, wariness, and outerdirectedness. Of the predictor variables, only MA was related to all three. As in earlier research, institutional variables were not predictive of the behaviors examined.

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A classification system of mental retardation was proposed based on etiology and IQs at least 2 SDs below the population mean. Social competence and performance capabilities of individuals with subaverage IQs were removed from definitional status and given prominence as correlates of class membership. The reliance on IQs to define mental retardation was predicated on the view that the behavioral sciences currently have no better measure of intellectual functioning, although promising efforts continue. The proclivity to avoid using the label "mentally retarded" was seen as ill-conducive to the betterment of knowledge in the field and detrimental to unlabeled individuals who are denied access to beneficial services.

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Retarded and nonretarded individuals matched on MA and CA were tested on role-taking, self-image, and imitation. Higher IQ, MA, real self-image, and ideal self-image were associated with less imitation. Higher IQ and MA were related to more positive ideal self-image, and higher MA was related to more positive real self-image. Retarded individuals had less positive real and ideal self-images compared to the nonretarded groups but were equal to the MA-matched nonretarded group on role-taking ability. The findings were interpreted as supporting the view that role-taking ability is a function of cognitive level and that self-image and imitation are determined by both cognitive and experiential factors.

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The authors compared the medical histories of incarcerated and nonincarcerated delinquent children. Incarcerated delinquent children were significantly more likely than nonincarcerated delinquents to have sustained severe head and face injury. Differences were evident by age 2. Perinatal difficulties and psychiatric impairment were also significantly more prevalent in the histories of incarcerated delinquents. Especially violent incarcerated children had more perinatal difficulties, accidents, injuries, and ward admissions than did their less violent incarcerated peers. The authors suggest that the combination of early CNS trauma, parental psychopathology, and social deprivation is responsible for the serious, often violent, delinquency that is now prevalent.

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In clinical practice the authors observed that many of the delinquent children of psychiatrically impaired and/or criminal parents had remarkably adverse health histories. To test their clinical impression they systematically compared the medical histories of 20 delinquent children with criminal parents and 85 delinquent children with less obviously maladapted parents. They found a strong association between paternal criminality and serious medical problems in these delinquent children. On the basis of this finding the authors suggest that the behavioral manifestations resulting from such physical illness or neglect, although they appear genetic in nature, may reflect the physical and psychological consequences of parental neglect and/or battering.

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A program of research on the effects of institutional experience on retarded persons was described. The importance of such research for theory construction, use by clinicians, and construction of social policy was discussed, as was the value of both longitudinal and cross-institutional studies. We stressed that any comprehensive understanding of the effects of institutional experience requires a consideration of: (a) the characteristics of the retarded person, (b) his preinstitutional life experience, (c) the nature of the institution, and (d) a range of criterion behavior on the part of the resident.

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This report explores some associations among juvenile-delinquency, subsequent criminality, and subsequent psychiatric treatment. A sample of 255 males known to the juvenile court 25 years prior to the study is examined in terms of subsequent documented psychiatric treatment and/or criminal activity. Of the 255 former delinquents, 6% were known later to both criminal justice and psychiatric systems, 6% to psychiatric systems only, 28% to the criminal justice system only, and 60% to neither. Delinquents with later psychiatric histories were twice as likely to be known to the criminal justice system than were those without psychiatric histories. Those with adult psychiatric histories were also significantly younger at the time of their first delinquent offense and committed more juvenile offenses than the nonpsychiatric group. Only 2 of the 16 individuals later known to both systems were diagnosed sociopathic. The findings are discussed.

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