Synthesis and characterization of n-type NiO:Al thin films for fabrication of p-n NiO homojunctions

NASA Astrophysics Data System (ADS)

Sun, Hui; Liao, Ming-Han; Chen, Sheng-Chi; Li, Zhi-Yue; Lin, Po-Chun; Song, Shu-Mei

2018-03-01

n-type NiO:Al thin films were deposited by RF magnetron sputtering. Their optoelectronic properties versus Al target power was investigated. The results show that with increasing Al target power, the conduction type of NiO films changes from p-type to n-type. The variation of the film’s electrical and optical properties depends on Al amount in the film. When Al target power is relatively low, Al3+ cations tend to enter nickel vacancy sites, which makes the lattice structure of NiO more complete. This improves the carrier mobility and film’s transmittance. However, when Al target power exceeds 40 W, Al atoms begin to enter into interstitial sites and form an Al cluster in the NiO film. This behavior is beneficial for improving the film’s n-type conductivity but degrades the film’s transmittance. Finally, Al/(p-type NiO)/(n-type NiO:Al)/ITO homojunctions were fabricated. Their performance was compared with Al/(p-type NiO)/ITO heterojunctions without an n-type NiO layer. Thanks to the better interface quality between the two NiO layers, the homojunctions present better performance.

Comprehensive study of the electronic and optical behavior of highly degenerate p-type Mg-doped GaN and AlGaN

NASA Astrophysics Data System (ADS)

Gunning, Brendan P.; Fabien, Chloe A. M.; Merola, Joseph J.; Clinton, Evan A.; Doolittle, W. Alan; Wang, Shuo; Fischer, Alec M.; Ponce, Fernando A.

2015-01-01

The bulk and 2-dimensional (2D) electrical transport properties of heavily Mg-doped p-type GaN films grown on AlN buffer layers by Metal Modulated Epitaxy are explored. Distinctions are made between three primary p-type conduction mechanisms: traditional valence band conduction, impurity band conduction, and 2D conduction within a 2D hole gas at a hetero-interface. The bulk and 2D contributions to the overall carrier transport are identified and the relative contributions are found to vary strongly with growth conditions. Films grown with III/V ratio less than 1.5 exhibit high hole concentrations exceeding 2 × 1019 cm-3 with effective acceptor activation energies of 51 meV. Films with III/V ratios greater than 1.5 exhibit lower overall hole concentrations and significant contributions from 2D transport at the hetero-interface. Films grown with III/V ratio of 1.2 and Mg concentrations exceeding 2 × 1020 cm-3 show no detectable inversion domains or Mg precipitation. Highly Mg-doped p-GaN and p-AlGaN with Al fractions up to 27% similarly exhibit hole concentrations exceeding 2 × 1019 cm-3. The p-GaN and p-Al0.11Ga0.89N films show broad ultraviolet (UV) photoluminescence peaks, which intercept the valence band, supporting the presence of a Mg acceptor band. Finally, a multi-quantum-well light-emitting diode (LED) and p-i-n diode are grown, both of which demonstrate rectifying behavior with turn-on voltages of 3-3.5 V and series resistances of 6-10 Ω without the need for any post-metallization annealing. The LED exhibits violet-blue luminescence at 425 nm, while the p-i-n diode shows UV luminescence at 381 nm, and both devices still show substantial light emission even when submerged in liquid nitrogen at 77 K.

Understanding and control of bipolar self-doping in copper nitride

NASA Astrophysics Data System (ADS)

Fioretti, Angela N.; Schwartz, Craig P.; Vinson, John; Nordlund, Dennis; Prendergast, David; Tamboli, Adele C.; Caskey, Christopher M.; Tuomisto, Filip; Linez, Florence; Christensen, Steven T.; Toberer, Eric S.; Lany, Stephan; Zakutayev, Andriy

2016-05-01

Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu3N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu3N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu3N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu3N with 1017 electrons/cm3 for low growth temperature (≈35 °C) and p-type with 1015 holes/cm3-1016 holes/cm3 for elevated growth temperatures (50 °C-120 °C). Mobility for both types of Cu3N was ≈0.1 cm2/Vs-1 cm2/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that VCu defects form preferentially in p-type Cu3N, while Cui defects form preferentially in n-type Cu3N, suggesting that Cu3N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu3N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.

Exploring effects of self-management on glycemic control using a modified information-motivation-behavioral skills model in type 2 diabetes mellitus patients in Shanghai, China: A cross-sectional study.

PubMed

Chen, Qi; Wang, Huwen; Wang, Yichen; Wang, Zezhou; Zhao, Daijun; Cai, Yong

2018-02-19

The original information-motivation-behavioral skills (IMB) model has been verified in type 2 diabetes mellitus (T2DM) patients, but the effects of the model on glycemic control remain unclear. The aim of this study was to modify the IMB model to explore the effects of self-management on glycemic control in T2DM patients in Shanghai, China. A cross-sectional study was conducted on participants recruited using a convenience sampling method between June and August 2015 in three tertiary hospitals and four community health service centers; 796 participants meeting the inclusion criteria (age ≥18 years and a diagnosis of T2DM) completed a questionnaire and blood test for glycemic control. Structural equation models were used to test the IMB framework. The modified model demonstrated an acceptable fit of the data. Paths from information to self-management behaviors (β = 0.119, P = 0.001) and HbA1c (β = -0.140, P < 0.001), from motivation to behavioral skills (β = 0.670, P < 0.001), from behavioral skills to self-management behaviors (β = 0.562, P < 0.001), and from self-management behaviors to HbA1c (β = -0.343, P < 0.001) were all significant and in the predicted direction. Information and motivation varied with each other (r = 0.350, P < 0.001). Glycemic control can be incorporated into the IMB model. The utility of the modified model in the study population is validated. Type 2 diabetes mellitus patients with poor control of glucose levels may be a better target population for application of the modified IMB model. © 2018 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

Effect of Playing Interactive Computer Game on Distress of Insulin Injection Among Type 1 Diabetic Children

PubMed Central

Ebrahimpour, Fatemeh; Sadeghi, Narges; Najafi, Mostafa; Iraj, Bijan; Shahrokhi, Akram

2015-01-01

Background: Diabetic children and their families experience high level stress because of daily insulin injection. Objectives: This study was conducted to investigate the impact of an interactive computer game on behavioral distress due to insulin injection among diabetic children. Patients and Methods: In this clinical trial, thirty children (3-12 years) with type 1 diabetes who needed daily insulin injection were recruited and allocated randomly into two groups. Children in intervention groups received an interactive computer game and asked to play at home for a week. No special intervention was done for control group. The behavioral distress of groups was assessed before, during and after the intervention by Observational Scale of Behavioral Distress–Revised (OSBD-R). Results: Repeated measure ANOVA test showed no significantly difference of OSBD-R over time for control group (P = 0.08), but this changes is signification in the study group (P = 0.001). Comparison mean score of distress were significantly different between two groups (P = 0.03). Conclusions: According to the findings, playing interactive computer game can decrease behavioral distress induced by insulin injection in type 1 diabetic children. It seems this game can be beneficial to be used alongside other interventions. PMID:26199708

Reliability and Validity of the Diabetes Eating Problem Survey in Turkish Children and Adolescents with Type 1 Diabetes Mellitus.

PubMed

Atik Altınok, Yasemin; Özgür, Suriye; Meseri, Reci; Özen, Samim; Darcan, Şükran; Gökşen, Damla

2017-12-15

The aim of this study was to show the reliability and validity of a Turkish version of Diabetes Eating Problem Survey-Revised (DEPS-R) in children and adolescents with type 1 diabetes mellitus. A total of 200 children and adolescents with type 1 diabetes, ages 9-18 years, completed the DEPS-R Turkish version. In addition to tests of validity, confirmatory factor analysis was conducted to investigate the factor structure of the 16-item Turkish version of DEPS-R. The Turkish version of DEPS-R demonstrated satisfactory Cronbach's ∝ (0.847) and was significantly correlated with age (r=0.194; p<0.01), hemoglobin A1c levels (r=0.303; p<0.01), and body mass index-standard deviation score (r=0.412; p<0.01) indicating criterion validity. Median DEPS-R scores of Turkish version for the total samples, females, and males were 11.0, 11.5, and 10.5, respectively. Disturbed eating behaviors and insulin restriction were associated with poor metabolic control. A short, self-administered diabetes-specific screening tool for disordered eating behavior can be used routinely in the clinical care of adolescents with type 1 diabetes. The Turkish version of DEPS-R is a valid screening tool for disordered eating behaviors in type 1 diabetes and it is potentially important to early detect disordered eating behaviors.

Polycrystalline ZrTe{sub 5} Parameterized as a Narrow Band Gap Semiconductor for Thermoelectric Performance.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Samuel A.; Witting, Ian; Aydemir, Umut

The transition-metal pentatellurides HfTe5 and ZrTe5 have been studied for their exotic transport properties with much debate over the transport mechanism, band gap, and cause of the resistivity behavior, including a large low-temperature resistivity peak. Single crystals grown by the chemical-vapor-transport method have shown an n-p transition of the Seebeck coefficient at the same temperature as a peak in the resistivity. We show that behavior similar to that of single crystals can be observed in iodine-doped polycrystalline samples but that undoped polycrystalline samples exhibit drastically different properties: they are p type over the entire temperature range. Additionally, the thermal conductivitymore » for polycrystalline samples is much lower, 1.5 Wm -1 K -1, than previously reported for single crystals. It is found that the polycrystalline ZrTe 5 system can be modeled as a simple semiconductor with conduction and valence bands both contributing to transport, separated by a band gap of 20 meV. This model demonstrates to first order that a simple two-band model can explain the transition from n- to p-type behavior and the cause of the anomalous resistivity peak. Combined with the experimental data, the two-band model shows that carrier concentration variation is responsible for differences in behavior between samples. Using the twoband model, the thermoelectric performance at different doping levels is predicted, finding zT =0.2 and 0.1 for p and n type, respectively, at 300 K, and zT= 0.23 and 0.32 for p and n type at 600 K. Given the reasonably high zT that is comparable in magnitude for both n and p type, a thermoelectric device with a single compound used for both legs is feasible.« less

Co-doping of CVD diamond with boron and sulfur

NASA Astrophysics Data System (ADS)

Eaton, Sally Catherine

Boron is well-established as a p-type dopant in diamond, but attempts to find a viable n-type dopant remain unsuccessful. In 1999, sulfur was reported to give n-type conductivity. However, later measurements indicated that the samples contained boron and were p-type. Recently, we showed that diamond co-doped with sulfur and small quantities of boron shows n-type conductivity, which was established by Mott-Schottky analyses, thermoelectric effect, Hall measurements, scanning tunneling spectroscopy (STS), and UV open-circuit photo-potential. At higher boron concentrations, a transition to p-type behavior is observed due to overcompensation. Experiments performed without boron in the feed gas or without residual boron in the reactor chamber showed no sulfur incorporation and no change in conductivity. There is evidence that the excess sulfur concentration in the near-surface region is not stable. At room temperature and below, the activation energies range from 0.06 to 0.12 eV. Above 400K there is an irreversible loss in conductivity and the activation energy increases to approximately 1.3 eV. Additionally, we observed by SIMS that there exists a concentration gradient in sulfur with film depth. This sulfur concentration gradient is also observed in our electrical measurements. STS shows a decrease in conductivity with film depth and Hall effect measurements show both p-type and n-type coefficients for samples which are n-type in the near-surface region. The flat-band potential obtained from the Mott-Schottky experiments is only 1 to 1.5 V more negative on the electrochemical scale than that for boron-doped diamond. This implies that the Fermi level is only 1 to 1.5 eV higher than the Fermi level in boron-doped diamond. This observation implies that the n-type conductivity is not by excitation of electrons to the conduction band, but by an alternate mechanism that occurs in the middle of the band gap. One such possibility is an acceptor impurity band. Electrons from individual donor states can be excited into this acceptor band where they are free to move. This mechanism would create n-type conductivity even if the Fermi level was low in the bandgap.

A self-powered nano-photodetector based on PFH/ZnO nanorods organic/inorganic heterojunction

NASA Astrophysics Data System (ADS)

Li, Xiaoyun; Liu, Wei; Li, Peigang; Song, Jia; An, Yuehua; Shen, Jingqin; Wang, Shunli; Guo, Daoyou

2018-03-01

PFH/ZnO nanorods heterojunctions were fabricated by spin-coating p-type Poly (9,9-dihexylfluorene) (PFH) on n-type vertically aligned ZnO nanorod arrays grown by a facile hydrothermal method on indium tin oxide (ITO) transparent conductive glass. A typical p-n junction behavior was observed in the fabricated heterojunction. The current of heterojunction increases and decreases dramatically by switching the illumination on and off at zero bias, showing potential self-powered photodetector applications. The heterojunction were capable of generating negative current when illuminated under an appropriate wavelength. The photoresponse properties of the heterojunction can be tuned by the applied bias. In vacuum, the rectifying behavior disappeared, and show only simple semiconductor behavior. Band structure of the heterojunction was schematic drawn and explain the mechanism of the properties of PFH/ZnO nanorods heterojunctions.

Corrosion Behavior of Steels in Supercritical CO 2 for Power Cycle Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Repukaiti, Richard; Teeter, Lucas; Ziomek-Moroz, Margaret

In order to understand issues with corrosion of heat exchanger materials in direct supercritical carbon dioxide (sCO 2) power cycles, a series of autoclave exposure experiments and electrochemical experiments have been conducted. Corrosion behaviors of 347H stainless steel and P91 martensitic-ferrtic steel in sCO 2 environment have been compared. In autoclave exposure tests performed at 50°C- 245°C and 80 bar. Mass change measurements, surface characterization, and corrosion product analysis have been conducted to understand the corrosion behavior of steels in sCO 2 containing H 2O and O 2. Electrochemical tests performed at room temperature and 50°C, a simulation environment ofmore » water condensation phase with dissolved CO 2 was prepared to evaluate the corrosion resistance of materials. From both types of experiments, generally 347H showed higher corrosion resistance than P91.« less

Steep Delay Discounting and Addictive Behavior: A Meta-Analysis of Continuous Associations

PubMed Central

Amlung, Michael; Vedelago, Lana; Acker, John; Balodis, Iris; MacKillop, James

2016-01-01

Aims To synthesize continuous associations between delayed reward discounting (DRD) and both addiction severity and quantity-frequency (QF); to examine moderators of these relationships; and to investigate publication bias. Methods Meta-analysis of published studies examining continuous associations between DRD and addictive behaviors. Published, peer-reviewed studies on addictive behaviors (alcohol, tobacco, cannabis, stimulants, opiates, and gambling) were identified via PubMed, MEDLINE, and PsycInfo. Studies were restricted to DRD measures of monetary gains. Random effects meta-analysis was conducted using Pearson’s r as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger’s tests, meta-regression of publication year and effect size, and imputation of missing studies. Results The primary meta-analysis revealed a small magnitude effect size that was highly significant (r = 0.14, p < 10−14). Significantly larger effect sizes were observed for studies examining severity compared with QF (p = 0.01), but not between the type of addictive behavior (p = 0.30) or DRD assessment (p = 0.90). Indices of publication bias suggested a modest impact of unpublished findings. Conclusions Delayed reward discounting is robustly associated with continuous measures of addiction severity and quantity-frequency. This relation is generally robust across type of addictive behavior and delayed reward discounting assessment modality. PMID:27450931

Comprehensive study of the electronic and optical behavior of highly degenerate p-type Mg-doped GaN and AlGaN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gunning, BP; Fabien, CAM; Merola, JJ

2015-01-28

The bulk and 2-dimensional (2D) electrical transport properties of heavily Mg-doped p-type GaN films grown on AlN buffer layers by Metal Modulated Epitaxy are explored. Distinctions are made between three primary p-type conduction mechanisms: traditional valence band conduction, impurity band conduction, and 2D conduction within a 2D hole gas at a hetero-interface. The bulk and 2D contributions to the overall carrier transport are identified and the relative contributions are found to vary strongly with growth conditions. Films grown with III/V ratio less than 1.5 exhibit high hole concentrations exceeding 2 x 10(19) cm(-3) with effective acceptor activation energies of 51more » meV. Films with III/V ratios greater than 1.5 exhibit lower overall hole concentrations and significant contributions from 2D transport at the hetero-interface. Films grown with III/V ratio of 1.2 and Mg concentrations exceeding 2 x 10(20) cm(-3) show no detectable inversion domains or Mg precipitation. Highly Mg-doped p-GaN and p-AlGaN with Al fractions up to 27% similarly exhibit hole concentrations exceeding 2 x 10(19) cm(-3). The p-GaN and p-Al0.11Ga0.89N films show broad ultraviolet (UV) photoluminescence peaks, which intercept the valence band, supporting the presence of a Mg acceptor band. Finally, a multi-quantum-well light-emitting diode (LED) and p-i-n diode are grown, both of which demonstrate rectifying behavior with turn-on voltages of 3-3.5V and series resistances of 6-10 Omega without the need for any post-metallization annealing. The LED exhibits violet-blue luminescence at 425 nm, while the p-i-n diode shows UV luminescence at 381 nm, and both devices still show substantial light emission even when submerged in liquid nitrogen at 77 K. (C) 2015 AIP Publishing LLC.« less

Comprehensive study of the electronic and optical behavior of highly degenerate p-type Mg-doped GaN and AlGaN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gunning, Brendan P.; Fabien, Chloe A. M.; Merola, Joseph J.

2015-01-28

The bulk and 2-dimensional (2D) electrical transport properties of heavily Mg-doped p-type GaN films grown on AlN buffer layers by Metal Modulated Epitaxy are explored. Distinctions are made between three primary p-type conduction mechanisms: traditional valence band conduction, impurity band conduction, and 2D conduction within a 2D hole gas at a hetero-interface. The bulk and 2D contributions to the overall carrier transport are identified and the relative contributions are found to vary strongly with growth conditions. Films grown with III/V ratio less than 1.5 exhibit high hole concentrations exceeding 2 × 10{sup 19} cm{sup −3} with effective acceptor activation energies of 51 meV.more » Films with III/V ratios greater than 1.5 exhibit lower overall hole concentrations and significant contributions from 2D transport at the hetero-interface. Films grown with III/V ratio of 1.2 and Mg concentrations exceeding 2 × 10{sup 20} cm{sup −3} show no detectable inversion domains or Mg precipitation. Highly Mg-doped p-GaN and p-AlGaN with Al fractions up to 27% similarly exhibit hole concentrations exceeding 2 × 10{sup 19} cm{sup −3}. The p-GaN and p-Al{sub 0.11}Ga{sub 0.89}N films show broad ultraviolet (UV) photoluminescence peaks, which intercept the valence band, supporting the presence of a Mg acceptor band. Finally, a multi-quantum-well light-emitting diode (LED) and p-i-n diode are grown, both of which demonstrate rectifying behavior with turn-on voltages of 3–3.5 V and series resistances of 6–10 Ω without the need for any post-metallization annealing. The LED exhibits violet-blue luminescence at 425 nm, while the p-i-n diode shows UV luminescence at 381 nm, and both devices still show substantial light emission even when submerged in liquid nitrogen at 77 K.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsuo, Hiroki; Kitanaka, Yuuki; Inoue, Ryotaro

We investigate the mechanism of a switchable diode behavior observed in ferroelectric SrRuO{sub 3}/BiFeO{sub 3} (BFO)/SrRuO{sub 3} capacitors. We experimentally demonstrate that the switchable diode effect observed in the capacitors is induced by the polarization reversal in the BFO film. The conductivity in an Ohmic region in different oxidation states provides direct evidence that electron hole acts as the majority carrier, delivering p-type conduction. Density functional theory (DFT) calculations show that the p-type conduction arises from an unoccupied gap state of Fe{sup 4+} in an FeO{sub 5} pyramid which is derived from Bi vacancy. Our experimental and DFT study leadsmore » to the conclusion that the switchable diode effect originates from an asymmetric band bending in the top and bottom depletion layers modulated by ferroelectric polarization and oxygen vacancies.« less

Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

NASA Astrophysics Data System (ADS)

Eom, Hyun-Jeong; Liu, Yuedan; Kwak, Gyu-Suk; Heo, Muyoung; Song, Kyung Seuk; Chung, Yun Doo; Chon, Tae-Soo; Choi, Jinhee

2017-06-01

We conducted an inhalation toxicity test on the alternative animal model, Drosophila melanogaster, to investigate potential hazards of indoor air pollution. The inhalation toxicity of toluene and formaldehyde was investigated using comprehensive transcriptomics and computational behavior analyses. The ingenuity pathway analysis (IPA) based on microarray data suggests the involvement of pathways related to immune response, stress response, and metabolism in formaldehyde and toluene exposure based on hub molecules. We conducted a toxicity test using mutants of the representative genes in these pathways to explore the toxicological consequences of alterations of these pathways. Furthermore, extensive computational behavior analysis showed that exposure to either toluene or formaldehyde reduced most of the behavioral parameters of both wild-type and mutants. Interestingly, behavioral alteration caused by toluene or formaldehyde exposure was most severe in the p38b mutant, suggesting that the defects in the p38 pathway underlie behavioral alteration. Overall, the results indicate that exposure to toluene and formaldehyde via inhalation causes severe toxicity in Drosophila, by inducing significant alterations in gene expression and behavior, suggesting that Drosophila can be used as a potential alternative model in inhalation toxicity screening.

Inhalation toxicity of indoor air pollutants in Drosophila melanogaster using integrated transcriptomics and computational behavior analyses

PubMed Central

Eom, Hyun-Jeong; Liu, Yuedan; Kwak, Gyu-Suk; Heo, Muyoung; Song, Kyung Seuk; Chung, Yun Doo; Chon, Tae-Soo; Choi, Jinhee

2017-01-01

We conducted an inhalation toxicity test on the alternative animal model, Drosophila melanogaster, to investigate potential hazards of indoor air pollution. The inhalation toxicity of toluene and formaldehyde was investigated using comprehensive transcriptomics and computational behavior analyses. The ingenuity pathway analysis (IPA) based on microarray data suggests the involvement of pathways related to immune response, stress response, and metabolism in formaldehyde and toluene exposure based on hub molecules. We conducted a toxicity test using mutants of the representative genes in these pathways to explore the toxicological consequences of alterations of these pathways. Furthermore, extensive computational behavior analysis showed that exposure to either toluene or formaldehyde reduced most of the behavioral parameters of both wild-type and mutants. Interestingly, behavioral alteration caused by toluene or formaldehyde exposure was most severe in the p38b mutant, suggesting that the defects in the p38 pathway underlie behavioral alteration. Overall, the results indicate that exposure to toluene and formaldehyde via inhalation causes severe toxicity in Drosophila, by inducing significant alterations in gene expression and behavior, suggesting that Drosophila can be used as a potential alternative model in inhalation toxicity screening. PMID:28621308

Isoelectronic tungsten doping in monolayer MoSe 2 for carrier type modulation

DOE PAGES

Li, Xufan; Lin, Ming -Wei; Basile, Leonardo; ...

2016-07-06

Doping and alloying are effective ways to engineer the band structure and modulate the optoelectronic functionality of monolayer transition metal dichalcogenides (TMDs). In this work, we explore the synthesis and electronic properties of monolayer Mo 1-xW xSe 2 (0 < x < 0.18) alloys with almost 100% alloying degree. The isoelectronic substitutional doping of tungsten for molybdenum in the monolayer MoSe 2 is shown to suppress its intrinsically n-type conduction behavior, with p-type conduction gradually emerging to become dominant with increasing W concentration in the alloys. Atomic resolution Z-contrast electron microscopy show that W is shown to substitute directly formore » Mo without the introduction of noticeable vacancy or interstitial defects, however with randomly-distributed W-rich regions ~2 nm in diameter. Scanning tunneling microscopy/spectroscopy measurements reveal that these W-rich regions exhibit a local band structure with the valence band maximum (VBM) closer to the Fermi level as compared with the Mo-rich regions in the monolayer Mo 1-xW xSe 2 crystal. These localized upshifts of the VBM in the local band structure appear responsible for the overall p-type behavior observed for the monolayer Mo 1-xW xSe 2 crystals. Stacked monolayers of n-type MoSe 2 and p-type Mo 1-xW xSe 2 were demonstrated to form atomically thin, vertically stacked p n homojunctions with gate-tunable characteristics, which appear useful for future optoelectronic applications. Lastly, these results indicate that alloying with isoelectronic dopant atoms appears to be an effective and advantageous alternate strategy to doping or alloying with electron donors or acceptors in two-dimensional TMDs.« less

Understanding and Control of Bipolar Self-Doping in Copper Nitride

PubMed Central

Fioretti, Angela N.; Schwartz, Craig P.; Vinson, John; Nordlund, Dennis; Prendergast, David; Tamboli, Adele C.; Caskey, Christopher M.; Tuomisto, Filip; Linez, Florence; Christensen, Steven T.; Toberer, Eric S.; Lany, Stephan; Zakutayev, Andriy

2016-01-01

Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu3N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu3N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu3N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu3N with an electron density of 1017 cm−3 for low growth temperature (≈ 35 °C) and p-type with a hole density between 1015 cm−3 and 1016 cm−3 for elevated growth temperatures (50 °C to 120 °C). Mobility for both types of Cu3N was ≈ 0.1 cm2/Vs to 1 cm2/V. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that VCu defects form preferentially in p-type Cu3N while Cui defects form preferentially in n-type Cu3N; suggesting that Cu3N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu3N, that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials, and provide a framework that can be applied when considering the properties of such materials in general. PMID:27746508

Understanding and Control of Bipolar Self-Doping in Copper Nitride

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fioretti, Angela N.; Schwartz, Craig P.; Vinson, John

2016-05-14

Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu3N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu3N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu3N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu3N with 1017 electrons/cm3 for low growth temperature (approximately 35more » degrees C) and p-type with 1015 holes/cm3-1016 holes/cm3 for elevated growth temperatures (50 degrees C-120 degrees C). Mobility for both types of Cu3N was approximately 0.1 cm2/Vs-1 cm2/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that VCu defects form preferentially in p-type Cu3N, while Cui defects form preferentially in n-type Cu3N, suggesting that Cu3N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defectformation mechanism for bipolar doping in Cu3N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.« less

High-Oriented Thermoelectric Nano-Bulk Fabricated from Thermoelectric Ink

NASA Astrophysics Data System (ADS)

Koyano, M.; Mizutani, S.; Hayashi, Y.; Nishino, S.; Miyata, M.; Tanaka, T.; Fukuda, K.

2017-05-01

Printing technology is expected to provide innovative and environmentally friendly processes for thermoelectric (TE) module fabrication. As described in this paper, we propose an orientation control process using plastic deformation at high temperatures and present high-oriented TE nano-bulks fabricated from bismuth telluride (Bi-Te) TE inks using this process. In the case of n-type Bi-Te, surface x-ray diffraction reveals that crystalline grains in the plastic-deformed nano-bulk demonstrate a c-plane orientation parallel to the pressed face. According to the high orientation, electrical resistivity ρ, thermal conductivity κ, and figure of merit ZT show anisotropic behavior. It is noteworthy that ( ZT)// almost reaches unity ( ZT)// ˜1 at 340 K, even at low temperatures of the plastic deformation process. In contrast, the ZT of plastic-deformed p-type nano-bulk indicates isotropic behavior. The difference in the process temperature dependence of ZT suggests that n-type and p-type nano-bulk orientation mechanisms mutually differ.

Promotion of acceptor formation in SnO2 nanowires by e-beam bombardment and impacts to sensor application

PubMed Central

Sub Kim, Sang; Gil Na, Han; Woo Kim, Hyoun; Kulish, Vadym; Wu, Ping

2015-01-01

We have realized a p-type-like conduction in initially n-type SnO2 nanowires grown using a vapor-liquid-solid method. The transition was achieved by irradiating n-type SnO2 nanowires with a high-energy electron beam, without intentional chemical doping. The nanowires were irradiated at doses of 50 and 150 kGy, and were then used to fabricate NO2 gas sensors, which exhibited n-type and p-type conductivities, respectively. The tuneability of the conduction behavior is assumed to be governed by the formation of tin vacancies (under high-energy electron beam irradiation), because it is the only possible acceptor, excluding all possible defects via density functional theory (DFT) calculations. The effect of external electric fields on the defect stability was studied using DFT calculations. The measured NO2 sensing dynamics, including response and recovery times, were well represented by the electron-hole compensation mechanism from standard electron-hole gas equilibrium statistics. This study elucidates the charge-transport characteristics of bipolar semiconductors that underlie surface chemical reactions. The principles derived will guide the development of future SnO2-based electronic and electrochemical devices. PMID:26030815

Effectiveness of Mindfulness Intervention on Psychological Behaviors Among Adolescents With Parental HIV Infection: A Group-Randomized Controlled Trial.

PubMed

Mon, Myo-Myo; Liabsuetrakul, Tippawan; Htut, Kyaw-Min

2016-11-01

This study aims to identify the effectiveness of mindfulness intervention on the psychological behaviors of adolescents with parental HIV infection and its associated factors in Myanmar. A total of 80 adolescents from 2 intervention townships and 80 adolescents from 2 control townships were enrolled in a group randomized controlled trial with assessments at baseline and 6 months follow-up. The mindfulness intervention involved monthly group sessions for 3 consecutive months led by an experienced mindfulness trainer. Three domains of psychological behaviors-namely, emotional, conduct, and social behaviors-were assessed at baseline and compared after 6 months. Multilevel regression analysis was used to determine the effectiveness of the intervention and associated factors for psychological behaviors. The intervention significantly improved emotional and conduct behaviors at 6 months (P < .001) but had no effect on social behavior. The significant effect of the intervention existed after adjusting for gender, family type, child age, and orphan status. © 2016 APJPH.

Health literacy, self-efficacy, and self-care behaviors in patients with type 2 diabetes mellitus.

PubMed

Bohanny, Walton; Wu, Shu-Fang Vivienne; Liu, Chieh-Yu; Yeh, Shu-Hui; Tsay, Shiow-Luan; Wang, Tsae-Jyy

2013-09-01

The study purpose was to explore the relationships among health literacy, self-efficacy, and self-care behaviors of patients with type 2 diabetes. A cross-sectional study with a descriptive correlational design was conducted. Patients (N = 150) with type 2 diabetes were recruited from diabetes clinics in the Marshall Islands. Levels of health literacy, self-efficacy, and self-care behaviors were assessed by a questionnaire. Health literacy, receiving diabetes education, and employment status together explained 11.8% of the variance in self-efficacy (F((3,147)) = 7.58, p < .001). Patients who had higher health literacy, received more diabetes-related education, were currently employed and had better self-efficacy. Self-efficacy and marital status together explained 16.7% of the variance in self-care behaviors (F((2,148)) = 15.96, p < .001). Patients who had higher self-efficacy and who were married had better self-care behaviors. Strategies are needed to incorporate the concept of self-efficacy in the design of diabetes education to promote patients' self-care behaviors, with an emphasis on dealing with hyper- or hypoglycemia, following the diet plan, and checking blood sugar levels as recommended. Diabetes education material that requires a lower literacy level may be needed for older or unemployed adult populations. ©2013 The Author(s) ©2013 American Association of Nurse Practitioners.

Behavioral economics survey of patients with type 1 and type 2 diabetes.

PubMed

Emoto, Naoya; Okajima, Fumitaka; Sugihara, Hitoshi; Goto, Rei

2015-01-01

Adherence to treatment and the metabolic control of diabetes are challenging in many patients with diabetes. The theory of neuroeconomics can provide important clues for understanding unreasonable human behavior concerning decisions between outcomes occurring at different time points. We investigated patients with type 1 and type 2 diabetes to determine whether patients who are at a risk of developing complications are less risk averse. We also examined whether patients with type 1 and type 2 diabetes have different behavioral traits in decision making under risk. We conducted a behavioral economics survey of 219 outpatients, 66 with type 1 diabetes and 153 with type 2 diabetes. All patients had been referred by general practitioners or other departments in the hospital. At the time of the survey, levels of hemoglobin A1c were not significantly different between patients with type 1 and type 2 diabetes. Patients with type 2 diabetes showed a lower response rate to the survey compared with patients with type 1 diabetes (71.9% vs 87.9%, P<0.01). Logistic regression analysis indicated that diabetic retinopathy was negatively associated with risk averse in pricing of hypothetical lotteries, myopic time preference, willingness to pay for preventive medicine, and levels of satisfaction with life. Diabetic nephropathy was also negatively associated with risk averse in pricing of hypothetical lotteries. Detailed analysis revealed that a lower proportion of patients with type 2 diabetes (22.7%) were categorized as risk averse compared with patients with type 1 diabetes (43.1%, P<0.05) in hypothetical lottery risk estimation. This is the first report that investigated patients with diabetes in a clinical setting using a method based on behavioral economics. The results suggest that the attitude of patients toward risk plays an important role in the progress of the complications of diabetes. Different educational and psychological approaches may be necessary to assess patients with diabetes based on whether they have traits such as risk seeking or risk averse.

A study of structural, electrical, and optical properties of p-type Zn-doped SnO2 films versus deposition and annealing temperature

NASA Astrophysics Data System (ADS)

Le, Tran; Phuc Dang, Huu; Luc, Quang Ho; Hieu Le, Van

2017-04-01

This study presents a detailed investigation of the structural, electrical, and optical properties of p-type Zn-doped SnO2 versus the deposition and annealing temperature. Using a direct-current (DC) magnetron sputtering method, p-type transparent conductive Zn-doped SnO2 (ZTO) films were deposited on quartz glass substrates. Zn dopants incorporated into the SnO2 host lattice formed the preferred dominant SnO2 (1 0 1) and (2 1 1) planes. X-ray photoelectron spectroscopy (XPS) was used for identifying the valence state of Zn in the ZTO film. The electrical property of ZTO films changed from n-type to p-type at the threshold temperature of 400 °C, and the films achieved extremely high conductivity at the optimum annealing temperature of 600 °C after annealing for 2 h. The best conductive property of the film was obtained on a 10 wt% ZnO-doped SnO2 target with a resistivity, hole concentration, and hole mobility of 0.22 Ω · cm, 7.19  ×  1018 cm-3, and 3.95 cm2 V-1 s-1, respectively. Besides, the average transmission of films was  >84%. The surface morphology of films was examined using scanning electron microscopy (SEM). Moreover, the acceptor level of Zn2+ was identified using photoluminescence spectra at room temperature. Current-voltage (I-V) characteristics revealed the behavior of a p-ZTO/n-Si heterojunction diode.

Magnitude, types and sex differentials of aggressive behaviour among school children in a rural area of West Bengal.

PubMed

Dutt, Debashis; Pandey, Girish Kumar; Pal, Dipak; Hazra, Suprakas; Dey, Tushar Kanti

2013-04-01

Aggression affects academic learning and emotional development, can damage school climate and if not controlled early and may precipitate extreme violence in the future. (1) To determine the magnitude and types of aggressive behavior in school children. (2) To identify the influence of age and sex on aggressive behavior. A cross-sectional study was conducted in Anandanagar High School, Singur village, West Bengal. Participants were 161 boys and 177 girls of classes VII to IX. The students were asked to complete a self-administered questionnaire indicating the types of aggressive behavior by them in the previous month and to assess themselves with reference to statements indicating verbal/physical aggression. Overall, 66.5% of the children were physically aggressive in the previous month: Boys 75.8%, girls 58.2% (P = 0.001); 56.8% were verbally aggressive: Boys 55.2%, girls 61% (P = 0.97). Verbal indirect passive aggression was more common among girls (55.3%) than among boys (22.3%) (P = 0.000 [1.17E(-09)]). Boys were more liable to physical aggression, viz. 60.2% of the boys would hit on provocation compared with only 9% of the girls (P = 0.000 [6.6E(-23)]). Regarding attributes indicating verbal aggression, girls were more argumentative (63.8%) than boys (55.2%) (P = 0.134) and disagreeing (41.8%) compared with boys (33.5%) (P = 0.145). With increasing age/class, physical direct active aggression decreased while physical indirect passive and verbal indirect passive aggression increased. No classes had been taken on anger control/management by school the authorities. Aggressive behavior was common both among boys and girls. Life skills education/counseling/classroom management strategies are recommended.

The association between sleep disturbances and suicidal behaviors in patients with psychiatric diagnoses: a systematic review and meta-analysis.

PubMed

Malik, Shaista; Kanwar, Amrit; Sim, Leslie A; Prokop, Larry J; Wang, Zhen; Benkhadra, Khalid; Murad, Mohammad Hassan

2014-02-25

Identifying patients with increased risk of suicidal behaviors is a constant challenge and concern for clinicians caring for patients with psychiatric conditions. We conducted a systematic review to assess the association between suicidal behaviors and sleep disturbances in psychiatric patients. A systematic literature search of Ovid Medline In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, Ovid PsycInfo, Ovid Cochrane Database of Systematic Reviews, Ovid Cochrane Central Register of Controlled Trials, and Scopus was conducted using earliest inclusive dates to 28 June 2013. Eligible studies were comparative observational studies that reported sleep disturbances in psychiatric patients and the outcome of interest (any type of suicidal behaviors). Pairs of reviewers extracted descriptive data, study quality, and outcomes. Odds ratios (OR) and 95% confidence intervals (CI) were pooled across studies using the random-effects model. Newcastle-Ottawa scale was used to critically appraise study quality. Nineteen studies met the inclusion criteria. Compared to those without sleep disturbances, patients with psychiatric diagnoses and co-morbid sleep disturbances were significantly more likely to report suicidal behaviors (OR = 1.99, 95% CI 1.72, 2.30, P <0.001). The association was also demonstrated across several psychiatric conditions including depression (OR = 3.05, 95% CI 2.07, 4.48, P <0.001), post-traumatic stress disorder (PTSD) (OR = 2.56, 95% CI 1.91, 3.43, P <0.001), panic disorder (OR = 3.22, 95% CI 1.09, 9.45, P = 0.03), and schizophrenia (OR = 12.66, 95% CI 1.40, 114.44, P = 0.02). In subgroup analysis based on the type of sleep disorder, we also found suicidal behavior to be significantly associated with the presence of insomnia, parasomnias, and sleep-related breathing disorders, but not hypersomnias. This systematic review and meta-analysis suggests that in patients with psychiatric diagnoses, sleep disturbances are associated with the increased risk of suicidal behaviors.

Low-temperature thermoelectric, galvanomagnetic, and thermodynamic properties of the type-I clathrate Ba8AuxSi46-x

NASA Astrophysics Data System (ADS)

Aydemir, U.; Candolfi, C.; Ormeci, A.; Oztan, Y.; Baitinger, M.; Oeschler, N.; Steglich, F.; Grin, Yu.

2011-11-01

Polycrystalline samples of the clathrate Ba8AuxSi46-x were synthesized for 0.2 ⩽ x ⩽ 10. The homogeneity range of the type-I clathrate phase was determined to be 3.63 ⩽ x ⩽ 6.10 after annealing at 900 °C, while a lower Au concentration (x ≈ 2.2) was obtained by steel-quenching. Quasisingle phase materials were obtained for 4.10 ⩽ x ⩽ 6.10. In this composition range, thermoelectric properties, including electrical resistivity, thermopower, and thermal conductivity, were investigated between 2 and 350 K. These experiments were complemented by low-temperature specific heat and Hall-effect measurements (2-300 K). First-principles calculations were carried out to determine the evolution of the electronic structure as a function of x. Both theoretical and experimental results evidence a progressive evolution, with the Au content, from a metallic-like behavior towards a highly doped semiconducting state which develops around x = 5.43. At this concentration, a crossover from n- to p-type conduction occurs, suggesting that the present system satisfies the Zintl-Klemm concept, which predicts a transition at x = 5.33. This crossover is traced by Hall-effect data indicating a dominant electronlike response for x ⩽ 5.43, which turns into a holelike signal at higher x values. Analysis of the data based on a single-parabolic-band model under the assumption of a single scattering mechanism of the charge carriers proved to adequately describe the transport properties in the compositional range investigated. Interestingly, the temperature dependence of the lattice thermal conductivity is strongly influenced by the Au concentration: the typical behavior of crystalline insulators in the n-type compounds evolves into a glasslike dependence in the p-type samples. The series Ba8AuxSi46-x thus provides an excellent testing ground for the interplay between crystal structure, electronic properties, and lattice thermal conductivity in type-I clathrates.

Stability of cp-Ti and Ti-6Al-4V alloy for dental implants as a function of saliva pH - an electrochemical study.

PubMed

Barão, Valentim A R; Mathew, Mathew T; Assunção, Wirley Gonçalves; Yuan, Judy Chia-Chun; Wimmer, Markus A; Sukotjo, Cortino

2012-09-01

To investigate the role of different levels of pH of artificial saliva under simulated oral environment on the corrosion behavior of commercially pure titanium (cp-Ti) and Ti-6Al-4V alloy. Special attention is given to understand the changes in corrosion kinetics and surface characterization of Ti by using electrochemical impedance spectroscopy (EIS). Fifty-four Ti disks (15-mm diameter, 2-mm thickness) were divided into six groups (n = 9) as a function of saliva pH (3, 6.5, and 9) and Ti type. Samples were mechanically polished using standard metallographic procedures. Standard electrochemical tests, such as open circuit potential, EIS, and potentiodynamic tests were conducted in a controlled environment. Data were evaluated by two-way ANOVA, Tukey multiple comparison test, and independent t-test (α = 0.05). Ti surfaces were examined using white-light-interferometry microscopy and scanning electron microscopy (SEM). Saliva pH level significantly affected the corrosion behavior of both Ti types. At low pH, acceleration of ions exchange between Ti and saliva, and reduction of resistance of Ti surface against corrosion were observed (P < 0.05). Corrosion rate was also significantly increased in acidic medium (P < 0.05). Similar corrosion behavior was observed for both Ti types. The white-light-interferometry images of Ti surfaces show higher surface changes at low pH level. SEM images do not show detectable changes. No pitting corrosion was observed for any group. The pH level of artificial saliva influences the corrosion behavior of cp-Ti and Ti-6Al-4V alloy in that lower pH accelerates the corrosion rate and kinetics. The corrosion products may mitigate the survival rate of dental implants. © 2011 John Wiley & Sons A/S.

Surface photovoltage studies of p-type AlGaN layers after reactive-ion etching

NASA Astrophysics Data System (ADS)

McNamara, J. D.; Phumisithikul, K. L.; Baski, A. A.; Marini, J.; Shahedipour-Sandvik, F.; Das, S.; Reshchikov, M. A.

2016-10-01

The surface photovoltage (SPV) technique was used to study the surface and electrical properties of Mg-doped, p-type AlxGa1-xN (0.06 < x < 0.17) layers. SPV measurements reveal significant deviation from previous SPV studies on p-GaN:Mg thin films and from the predictions of a thermionic model for the SPV behavior. In particular, the SPV of the p-AlGaN:Mg layers exhibited slower-than-expected transients under ultraviolet illumination and delayed restoration to the initial dark value. The slow transients and delayed restorations can be attributed to a defective surface region which interferes with normal thermionic processes. The top 45 nm of the p-AlGaN:Mg layer was etched using a reactive-ion etch which caused the SPV behavior to be substantially different. From this study, it can be concluded that a defective, near-surface region is inhibiting the change in positive surface charge by allowing tunneling or hopping conductivity of holes from the bulk to the surface, or by the trapping of electrons traveling to the surface by a high concentration of defects in the near-surface region. Etching removes the defective layer and reveals a region of presumably higher quality, as evidenced by substantial changes in the SPV behavior.

Insertion of a pentacene layer into the gold/poly(methyl methacrylate)/heavily doped p-type Si/indium device leading to the modulation of resistive switching characteristics

NASA Astrophysics Data System (ADS)

Hung, Cheng-Chun; Lin, Yow-Jon

2018-01-01

In order to get a physical insight into the pentacene interlayer-modulated resistive switching (RS) characteristics, the Au/pentacene/poly(methyl methacrylate) (PMMA)/heavily doped p-type Si (p+-Si)/In and Au/PMMA/p+-Si/In devices are fabricated and the device performance is provided. The Au/pentacene/PMMA/p+-Si/In device shows RS behavior, whereas the Au/PMMA/p+-Si/In device exhibits the set/reset-free hysteresis current-voltage characteristics. The insertion of a pentacene layer is a noticeable contribution to the RS characteristic. This is because of the occurrence of carrier accumulation/depletion in the pentacene interlayer. The transition from carrier depletion to carrier accumulation (carrier accumulation to carrier depletion) in pentacene occurring under negative (positive) voltage induces the process of set (reset). The switching conduction mechanism is primarily described as space charge limited conduction according to the electrical transport properties measurement. The concept of a pentacene/PMMA heterostructure opens a promising direction for organic memory devices.

Colossal change in thermopower with temperature-driven p-n-type conduction switching in La x Sr2-x TiFeO6 double perovskites

NASA Astrophysics Data System (ADS)

Roy, Pinku; Maiti, Tanmoy

2018-02-01

Double perovskite materials have been studied in detail by many researchers, as their magnetic and electronic properties can be controlled by the substitution of alkaline earth metals or lanthanides in the A site and transition metals in the B site. Here we report the temperature-driven, p-n-type conduction switching assisted, large change in thermopower in La3+-doped Sr2TiFeO6-based double perovskites. Stoichiometric compositions of La x Sr2-x TiFeO6 (LSTF) with 0  ⩽  x  ⩽  0.25 were synthesized by the solid-state reaction method. Rietveld refinement of room-temperature XRD data confirmed a single-phase solid solution with cubic crystal structure and Pm\\bar{3}m space group. From temperature-dependent electrical conductivity and Seebeck coefficient (S) studies it is evident that all the compositions underwent an intermediate semiconductor-to-metal transition before the semiconductor phase reappeared at higher temperature. In the process of semiconductor-metal-semiconductor transition, LSTF compositions demonstrated temperature-driven p-n-type conduction switching behavior. The electronic restructuring which occurs due to the intermediate metallic phase between semiconductor phases leads to the colossal change in S for LSTF oxides. The maximum drop in thermopower (ΔS ~ 2516 µV K-1) was observed for LSTF with x  =  0.1 composition. Owing to their enormous change in thermopower of the order of millivolts per kelvin, integrated with p-n-type resistance switching, these double perovskites can be used for various high-temperature multifunctional device applications such as diodes, sensors, switches, thermistors, thyristors, thermal runaway monitors etc. Furthermore, the conduction mechanisms of these oxides were explained by the small polaron hopping model.

Difference in charge transport properties of Ni-Nb thin films with native and artificial oxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trifonov, A. S., E-mail: trifonov.artem@phys.msu.ru; Physics Faculty, Lomonosov Moscow State University, Moscow 119991; Lubenchenko, A. V.

2015-03-28

Here, we report on the properties of native and artificial oxide amorphous thin film on a surface of an amorphous Ni-Nb sample. Careful measurements of local current-voltage characteristics of the system Ni-Nb / NiNb oxide/Pt, were carried out in contact mode of an atomic force microscope. Native oxide showed n-type conductivity, while in the artificial one exhibited p-type one. The shape of current-voltage characteristic curves is unique in both cases and no analogical behavior is found in the literature. X-ray photoelectron spectroscopy (XPS) measurements were used to detect chemical composition of the oxide films and the oxidation state of themore » alloy components. Detailed analysis of the XPS data revealed that the structure of natural Ni-Nb oxide film consists of Ni-NbO{sub x} top layer and nickel enriched bottom layer which provides n-type conductivity. In contrast, in the artificial oxide film Nb is oxidized completely to Nb{sub 2}O{sub 5}, Ni atoms migrate into bulk Ni-Nb matrix. Electron depletion layer is formed at the Ni-Nb/Nb{sub 2}O{sub 5} interface providing p-type conductivity.« less

Understanding and control of bipolar self-doping in copper nitride

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fioretti, Angela N., E-mail: afiorett@mines.edu, E-mail: riy.zakutayev@nrel.gov; Tamboli, Adele C.; Caskey, Christopher M.

2016-05-14

Semiconductor materials that can be doped both n-type and p-type are desirable for diode-based applications and transistor technology. Copper nitride (Cu{sub 3}N) is a metastable semiconductor with a solar-relevant bandgap that has been reported to exhibit bipolar doping behavior. However, deeper understanding and better control of the mechanism behind this behavior in Cu{sub 3}N is currently lacking in the literature. In this work, we use combinatorial growth with a temperature gradient to demonstrate both conduction types of phase-pure, sputter-deposited Cu{sub 3}N thin films. Room temperature Hall effect and Seebeck effect measurements show n-type Cu{sub 3}N with 10{sup 17} electrons/cm{sup 3}more » for low growth temperature (≈35 °C) and p-type with 10{sup 15} holes/cm{sup 3}–10{sup 16} holes/cm{sup 3} for elevated growth temperatures (50 °C–120 °C). Mobility for both types of Cu{sub 3}N was ≈0.1 cm{sup 2}/Vs–1 cm{sup 2}/Vs. Additionally, temperature-dependent Hall effect measurements indicate that ionized defects are an important scattering mechanism in p-type films. By combining X-ray absorption spectroscopy and first-principles defect theory, we determined that V{sub Cu} defects form preferentially in p-type Cu{sub 3}N, while Cu{sub i} defects form preferentially in n-type Cu{sub 3}N, suggesting that Cu{sub 3}N is a compensated semiconductor with conductivity type resulting from a balance between donor and acceptor defects. Based on these theoretical and experimental results, we propose a kinetic defect formation mechanism for bipolar doping in Cu{sub 3}N that is also supported by positron annihilation experiments. Overall, the results of this work highlight the importance of kinetic processes in the defect physics of metastable materials and provide a framework that can be applied when considering the properties of such materials in general.« less

Electrical and structural characterization of plasma polymerized polyaniline/TiO2 heterostructure diode: a comparative study of single and bilayer TiO2 thin film electrode.

PubMed

Ameen, Sadia; Akhtar, M Shaheer; Kimi, Young Soon; Yang, O-Bong; Shin, Hyung-Shik

2011-04-01

A heterostructure was fabricated using p-type plasma polymerized polyaniline (PANI) and n-type (single and bilayer) titanium dioxide (TiO2) thin film on FTO glass. The deposition of single and bilayer TiO2 thin film on FTO substrate was achieved through doctor blade followed by dip coating technique before subjected to plasma enhanced polymerization. To fabricate p-n heterostructure, a plasma polymerization of aniline was conducted using RF plasma at 13.5 MHz and at the power of 120 W on the single and bilayer TiO2 thin film electrodes. The morphological, optical and the structural characterizations revealed the formation of p-n heterostructures between PANI and TiO2 thin film. The PANI/bilayer TiO2 heterostructure showed the improved current-voltage (I-V) characteristics due to the substantial deposition of PANI molecules into the bilayer TiO2 thin film which provided good conducting pathway and reduced the degree of excitons recombination. The change of linear I-V behavior of PANI/TiO2 heterostructure to non linear behavior with top Pt contact layer confirmed the formation of Schottky contact at the interfaces of Pt layer and PANI/TiO2 thin film layers.

Optical and electronic properties of doped p -type CuI: Explanation of transparent conductivity from first principles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuwei; Sun, Jifeng; Singh, David J.

In this paper, we report the properties of the reported transparent conductor CuI, including the effect of heavy p-type doping. The results, based on first-principles calculations, include an analysis of the electronic structure and calculations of optical and dielectric properties. We find that the origin of the favorable transparent conducting behavior lies in the absence in the visible of strong interband transitions between deeper valence bands and states at the valence-band maximum that become empty with p-type doping. Instead, strong interband transitions to the valence-band maximum are concentrated in the infrared with energies below 1.3 eV. This is contrast tomore » the valence bands of many wide-band-gapmaterials. Turning to the mobility,we find that the states at the valence-band maximum are relatively dispersive. This originates from their antibonding Cu d–I p character. We find a modest enhancement of the Born effective charges relative to nominal values, leading to a dielectric constant ε(0) = 6.3. This is sufficiently large to reduce ionized impurity scattering, leading to the expectation that the properties of CuI can still be significantly improved through sample quality.« less

Optical and electronic properties of doped p -type CuI: Explanation of transparent conductivity from first principles

DOE PAGES

Li, Yuwei; Sun, Jifeng; Singh, David J.

2018-03-26

In this paper, we report the properties of the reported transparent conductor CuI, including the effect of heavy p-type doping. The results, based on first-principles calculations, include an analysis of the electronic structure and calculations of optical and dielectric properties. We find that the origin of the favorable transparent conducting behavior lies in the absence in the visible of strong interband transitions between deeper valence bands and states at the valence-band maximum that become empty with p-type doping. Instead, strong interband transitions to the valence-band maximum are concentrated in the infrared with energies below 1.3 eV. This is contrast tomore » the valence bands of many wide-band-gapmaterials. Turning to the mobility,we find that the states at the valence-band maximum are relatively dispersive. This originates from their antibonding Cu d–I p character. We find a modest enhancement of the Born effective charges relative to nominal values, leading to a dielectric constant ε(0) = 6.3. This is sufficiently large to reduce ionized impurity scattering, leading to the expectation that the properties of CuI can still be significantly improved through sample quality.« less

An evaluation of soluble cations and anions on the conductivity and rate of flocculation of kaolins

NASA Astrophysics Data System (ADS)

Fulton, Deborah Lee

1998-10-01

The focus of this project was to learn how ionic concentrations and their contributions to electric conductivity influence the flocculation behavior of kaolin/water suspensions. Sodium silicate, calcium chloride, and magnesium sulfate were used as chemical additives. The specific surface areas, particle size distributions, and methylene blue indices for two kaolins were measured. The SSA and MBI for these kaolins indicated that they possessed inherent differences in SSA and flocculation behaviors. Rheological studies were also performed. Testing included simultaneous gelation, deflocculation, and pH tests. Viscosity, pH, temperature, and chemical additive concentrations were monitored at each point. Testing was performed at 45/55 wt% solids. Effects of additions of various levels of deflocculant and flocculant to each of the kaolin/water suspensions were studied by making several suspensions from each kaolin. The concentrations of dispersant, and flocculant levels and types were varied to produce suspensions with different chemical additive "histories," but all with similar final apparent viscosities. Slurry filtrates were analyzed for conductivity, pH, temperature, and ion concentrations of (Al3+, Fe2+,3+, Ca 2+, Mg+, Na+, SO4 2--, and Cl--). Plastic properties were calculated to determine how variations in suspension histories affected conductivities, pH, and detectable ion contents of the suspensions. These analyses were performed on starting slurries which were under-, completely-, and over-deflocculated before further additions of flocculants and deflocculant were added to tune the slurries to the final, constant, target viscosity. Results showed that rates of flocculation and conductivities increased as concentrations of ions increased. By increasing conductivity correlations with increases in flocculation occurs, which yields higher rates of buildup, or RBU [1]. This is the single most important slip control property in the whitewares industry. Shear-thinning behavior of the bodies also increased with increases in ion concentrations and conductivities. Bingham viscosities decreased as ionic concentrations increased. Brookfield buildup (BBU), plasticity index, yield stress, and pseudoplastic index generally increased as chemical additions increased. Softness and plastic behavior of the bodies increased with increasing concentrations of additive chemicals and with increasing conductivity. Calcium, sodium, and sulfate ions were primarily responsible for increasing conductivity. Calcium chloride was a more effective flocculant than magnesium sulfate.

Poole-Frenkel effect on electrical characterization of Al-doped ZnO films deposited on p-type GaN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Bohr-Ran; Liao, Chung-Chi; Ke, Wen-Cheng, E-mail: wcke@saturn.yzu.edu.tw

2014-03-21

This paper presents the electrical properties of Al-doped ZnO (AZO) films directly grown on two types of p-type GaN thin films. The low-pressure p-GaN thin films (LP-p-GaN) exhibited structural properties of high-density edge-type threading dislocations (TDs) and compensated defects (i.e., nitrogen vacancy). Compared with high-pressure p-GaN thin films (HP-p-GaN), X-ray photoemission spectroscopy of Ga 3d core levels indicated that the surface Fermi-level shifted toward the higher binding-energy side by approximately 0.7 eV. The high-density edge-type TDs and compensated defects enabled surface Fermi-level shifting above the intrinsic Fermi-level, causing the surface of LP-p-GaN thin films to invert to n-type semiconductor. A highlymore » nonlinear increase in leakage current regarding reverse-bias voltage was observed for AZO/LP-p-GaN. The theoretical fits for the reverse-bias voltage region indicated that the field-assisted thermal ionization of carriers from defect associated traps, which is known as the Poole-Frenkel effect, dominated the I-V behavior of AZO/LP-p-GaN. The fitting result estimated the trap energy level at 0.62 eV below the conduction band edge. In addition, the optical band gap increased from 3.50 eV for as-deposited AZO films to 3.62 eV for 300 °C annealed AZO films because of the increased carrier concentration. The increasing Fermi-level of the 300 °C annealed AZO films enabled the carrier transport to move across the interface into the LP-p-GaN thin films without any thermal activated energy. Thus, the Ohmic behavior of AZO contact can be achieved directly on the low-pressure p-GaN films at room temperature.« less

Poole-Frenkel effect on electrical characterization of Al-doped ZnO films deposited on p-type GaN

NASA Astrophysics Data System (ADS)

Huang, Bohr-Ran; Liao, Chung-Chi; Ke, Wen-Cheng; Chang, Yuan-Ching; Huang, Hao-Ping; Chen, Nai-Chuan

2014-03-01

This paper presents the electrical properties of Al-doped ZnO (AZO) films directly grown on two types of p-type GaN thin films. The low-pressure p-GaN thin films (LP-p-GaN) exhibited structural properties of high-density edge-type threading dislocations (TDs) and compensated defects (i.e., nitrogen vacancy). Compared with high-pressure p-GaN thin films (HP-p-GaN), X-ray photoemission spectroscopy of Ga 3d core levels indicated that the surface Fermi-level shifted toward the higher binding-energy side by approximately 0.7 eV. The high-density edge-type TDs and compensated defects enabled surface Fermi-level shifting above the intrinsic Fermi-level, causing the surface of LP-p-GaN thin films to invert to n-type semiconductor. A highly nonlinear increase in leakage current regarding reverse-bias voltage was observed for AZO/LP-p-GaN. The theoretical fits for the reverse-bias voltage region indicated that the field-assisted thermal ionization of carriers from defect associated traps, which is known as the Poole-Frenkel effect, dominated the I-V behavior of AZO/LP-p-GaN. The fitting result estimated the trap energy level at 0.62 eV below the conduction band edge. In addition, the optical band gap increased from 3.50 eV for as-deposited AZO films to 3.62 eV for 300 °C annealed AZO films because of the increased carrier concentration. The increasing Fermi-level of the 300 °C annealed AZO films enabled the carrier transport to move across the interface into the LP-p-GaN thin films without any thermal activated energy. Thus, the Ohmic behavior of AZO contact can be achieved directly on the low-pressure p-GaN films at room temperature.

Carrier polarity engineering in carbon nanotube field-effect transistors by induced charges in polymer insulator

NASA Astrophysics Data System (ADS)

Aikawa, Shinya; Kim, Sungjin; Thurakitseree, Theerapol; Einarsson, Erik; Inoue, Taiki; Chiashi, Shohei; Tsukagoshi, Kazuhito; Maruyama, Shigeo

2018-01-01

We present that the electrical conduction type in carbon nanotube field-effect transistors (CNT-FETs) can be converted by induced charges in a polyvinyl alcohol (PVA) insulator. When the CNT channels are covered with pure PVA, the FET characteristics clearly change from unipolar p-type to ambipolar. The addition of ammonium ions (NH4+) in the PVA leads to further conversion to unipolar n-type conduction. The capacitance - voltage characteristics indicate that a high density of positive charges is induced at the PVA/SiO2 interface and within the bulk PVA. Electrons are electrostatically accumulated in the CNT channels due to the presence of the positive charges, and thus, stable n-type conduction of PVA-coated CNT-FETs is observed, even under ambient conditions. The mechanism for conversion of the conduction type is considered to be electrostatic doping due to the large amount of positive charges in the PVA. A blue-shift of the Raman G-band peak was observed for CNTs coated with NH4+-doped PVA, which corresponds to unipolar n-type CNT-FET behavior. These results confirm that carrier polarity engineering in CNT-FETs can be achieved with a charged PVA passivation layer.

PubMed Central

SARTINI, M.; PANATTO, D.; PERDELLI, F.; CRISTINA, M.L.

2013-01-01

Summary An experimental study was conducted in a hospital in Liguria (northern Italy) on two groups of patients with the same disease severity who were undergoing the same type of surgery (primary hemiarthroplasty). Our aim was to assessing the results of a quality- improvement scheme implemented in the operating room. The quality-improvement protocol involved analyzing a set of parameters concerning the operating team's behavior and environmental conditions that could be attributed to the operating team itself. A program of training and sanitary education was carried to rectify any improper behavior of the operating staff. Two hundred and six hip-joint replacement operations (primary hip hemiarthroplasty - ICD9-CM 81.51) all conducted in the same operating room were studied: 103 patients, i.e. operations performed before the quality-improvement scheme and 103 patients, i.e. operations performed after the quality improvement scheme; all were comparable in terms of type of surgery and severity. The scheme resulted in an improvement in both behavioral and environmental parameters and an 80% reduction in the level of microbial air contamination (p < 0.001). Patient outcomes improved in terms of average postoperative hospitalization time, the occurrence and duration of fever (>37.5°C) and microbiological contamination of surgical wounds. From an economic point of view, facility efficiency increased by 28.57%, average hospitalization time decreased (p<0.001) and a theoretical increase of € 1,441,373.58 a year in revenues was achieved. PMID:24396985

Behavioral economics survey of patients with type 1 and type 2 diabetes

PubMed Central

Emoto, Naoya; Okajima, Fumitaka; Sugihara, Hitoshi; Goto, Rei

2015-01-01

Background Adherence to treatment and the metabolic control of diabetes are challenging in many patients with diabetes. The theory of neuroeconomics can provide important clues for understanding unreasonable human behavior concerning decisions between outcomes occurring at different time points. Objective We investigated patients with type 1 and type 2 diabetes to determine whether patients who are at a risk of developing complications are less risk averse. We also examined whether patients with type 1 and type 2 diabetes have different behavioral traits in decision making under risk. Methods We conducted a behavioral economics survey of 219 outpatients, 66 with type 1 diabetes and 153 with type 2 diabetes. All patients had been referred by general practitioners or other departments in the hospital. At the time of the survey, levels of hemoglobin A1c were not significantly different between patients with type 1 and type 2 diabetes. Results Patients with type 2 diabetes showed a lower response rate to the survey compared with patients with type 1 diabetes (71.9% vs 87.9%, P<0.01). Logistic regression analysis indicated that diabetic retinopathy was negatively associated with risk averse in pricing of hypothetical lotteries, myopic time preference, willingness to pay for preventive medicine, and levels of satisfaction with life. Diabetic nephropathy was also negatively associated with risk averse in pricing of hypothetical lotteries. Detailed analysis revealed that a lower proportion of patients with type 2 diabetes (22.7%) were categorized as risk averse compared with patients with type 1 diabetes (43.1%, P<0.05) in hypothetical lottery risk estimation. Conclusion This is the first report that investigated patients with diabetes in a clinical setting using a method based on behavioral economics. The results suggest that the attitude of patients toward risk plays an important role in the progress of the complications of diabetes. Different educational and psychological approaches may be necessary to assess patients with diabetes based on whether they have traits such as risk seeking or risk averse. PMID:25999700

A meta-analysis of the relationship between organizational citizenship behavior and counterproductive work behavior.

PubMed

Dalal, Reeshad S

2005-11-01

Job performance is increasingly being seen to encompass constructs such as organizational citizenship behavior (OCB) and counterproductive work behavior (CWB). To clarify the OCB-CWB relationship, a meta-analysis was conducted. Results indicate a modest negative relationship (p = -0.32). The relationship strength did not increase appreciably when the target of the behavior (the organization vs. other employees) was the same. Moreover, OCB and CWB exhibited somewhat distinct patterns of relationships with antecedents. The OCB-CWB relationship was moderated by the source of the ratings, the presence of antithetical items, and the type of response options. An employee-centric perspective is proposed whereby both OCB and CWB are perceived as adaptive behavior. Implications for organizations are discussed. ((c) 2005 APA, all rights reserved).

Unsafe sexual behaviors among HIV-positive men and women in Honduras: the role of discrimination, condom access, and gender.

PubMed

Paz-Bailey, Gabriela; Isern Fernandez, Virginia; Morales Miranda, Sonia; Jacobson, Jerry O; Mendoza, Suyapa; Paredes, Mayte A; Danaval, Damien C; Mabey, David; Monterroso, Edgar

2012-01-01

We conducted a study among HIV-positive men and women in Honduras to describe demographics, HIV risk behaviors and sexually transmitted infection prevalence, and identify correlates of unsafe sex. Participants were recruited from HIV clinics and nongovernmental organizations in Tegucigalpa and San Pedro Sula, Honduras in a cross-sectional study in 2006. We used audio-assisted computer interviews on demographics; behaviors in the past 12 months, 6 months, and 30 days; and access to care. Assays performed included herpes (HSV-2 Herpes Select), syphilis (rapid plasma reagin [RPR] and Treponema pallidum particle agglutination assay [TPPA]) serology, and other sexually transmitted infections by polymerase chain reaction (PCR). Bivariate and multivariate analyses were conducted to assess variables associated with unprotected sex across all partner types in the past 12 months. Of 810 participants, 400 were from Tegucigalpa and 410 from San Pedro Sula; 367 (45%) were men. Mean age was 37 years (interquartile range: 31-43). Consistent condom use for men and women was below 60% for all partner types. In multivariate analysis, unprotected sex was more likely among women (odds ratio [OR]: 1.9, 95% confidence interval [CI]: 1.2-3.1, P = 0.007), those with HIV diagnoses within the past year (OR: 2.0, 95% CI: 1.1-3.7, P = 0.016), those reporting difficulty accessing condoms (OR: 2.6, 95% CI: 1.4-4.7, P = 0.003), and those reporting discrimination (OR: 1.8, 95% CI: 1.1-3.0, P = 0.016). Programs targeting HIV-positive patients need to address gender-based disparities, improve condom access and use, and help establish a protective legal and policy environment free of stigma and discrimination.

Modeling the effect of 1 MeV electron irradiation on the performance of n+-p-p+ silicon space solar cells

NASA Astrophysics Data System (ADS)

Hamache, Abdelghani; Sengouga, Nouredine; Meftah, Afak; Henini, Mohamed

2016-06-01

Energetic particles such as electrons and protons induce severe degradation on the performance of solar cells used to power satellites and space vehicles. This degradation is usually attributed to lattice damage in the active region of the solar cell. One of the phenomena observed in silicon solar cells exposed to 1 MeV electron irradiation is the anomalous degradation of the short circuit current. It initially decreases followed by a recovery before falling again with increasing electron fluence. This behavior is usually attributed to type conversion of the solar cell active region. The other figures of merit, on the other hand, decrease monotonically. In this work numerical simulator SCAPS (Solar Cell Capacitance Simulator) is used to elucidate this phenomenon. The current-voltage characteristics of a Si n+-p-p+ structure are calculated under air mass zero spectrum with the fluence of 1 MeV electrons as a variable parameter. The effect of irradiation on the solar cell is simulated by a set of defects of which the energy levels lie deep in energy gap of silicon (much larger than the characteristic thermal energy kT far from either the conduction or valence band). Although several types of deep levels are induced by irradiation including deep donors (exchange electrons mainly with the conduction band), deep acceptors (exchange electrons mainly with the valence band) and/or generation-recombination centers (exchange electrons with both the conduction and valence bands), it was found that, only one of them (the shallowest donor) is responsible for the anomalous degradation of the short circuit current. It will be also shown, by calculating the free charge carrier profile in the active region, that this behavior is not related to type conversion but to a lateral widening of the space charge region.

Effect of pH on the electrical properties and conducting mechanism of SnO2 nanoparticles

NASA Astrophysics Data System (ADS)

Periathai, R. Sudha; Abarna, S.; Hirankumar, G.; Jeyakumaran, N.; Prithivikumaran, N.

2017-03-01

Semiconductor nanoparticles have attracted more interests because of their size-dependent optical and electrical properties.SnO2 is an oxygen-deficient n-type semiconductor with a wide band gap of 3.6 eV (300 K). It has many remarkable applications as sensors, catalysts, transparent conducting electrodes, anode material for rechargeable Li- ion batteries and optoelectronic devices. In the present work, the role of pH in determining the electrical and dielectric properties of SnO2 nanoparticles has been studied as a function of temperature ranging from Room temperature (RT) to 114 °C in the frequency range of 7 MHz to 50 mHz using impedance spectroscopic technique. The non linear behavior observed in the thermal dependence of the conductance of SnO2 nanoparticles is explained by means of the surface property of SnO2 nanoparticles where proton hopping mechanism is dealt with. Jonscher's power law has been fitted for the conductance spectra and the frequency exponent ("s" value) gives an insight about the ac conducting mechanism. The temperature dependence of electrical relaxation phenomenon in the material has been observed. The complex electric modulus analysis indicates the possibility of hopping conduction mechanism in the system with non-exponential type of conductivity relaxation.

AlN/ITO-Based Hybrid Electrodes with Conducting Filaments: Their Application to Ultraviolet Light-Emitting Diodes.

PubMed

Kim, Kyeong Heon; Lee, Tae Ho; Kim, Tae Geun

2017-07-19

A hybrid-type transparent conductive electrode (H-TCE) structure comprising an AlN rod array with conducting filaments (CFs) and indium tin oxide (ITO) films is proposed to improve both current injection and distribution as well as optical transmittance in the UV region. These CFs, generated in UV-transparent AlN rod areas using an electric field, can be used as conducting paths for carrier injection from a metal to a semiconductor such as p-(Al)GaN, which allows perfect Ohmic behavior with high transmittance (>95% at 365 nm) to be obtained. In addition, conduction across AlN rods and Ohmic conduction mechanisms are investigated by analyzing AlN rods and AlN rod/p-AlGaN film interfaces. We apply these H-TCEs to three near-UV light-emitting diodes (LEDs) (385 nm LEDs with p-GaN and p-AlGaN terminated surfaces and 365 nm LED with p-AlGaN terminated surface). We confirm that the light power outputs increase by 66%, 79%, and 103%, whereas the forward voltages reduce by 5.6%, 10.2%, and 8.6% for 385 nm p-GaN terminated, 385 nm p-AlGaN terminated, and 365 nm p-AlGaN terminated LEDs with H-TCEs, respectively, compared to LEDs with reference ITOs.

Electrical conduction and thermoelectric properties of perovskite-type BaBi1-xSbxO3

NASA Astrophysics Data System (ADS)

Yasukawa, Masahiro; Shiga, Yuta; Kono, Toshio

2012-06-01

To elucidate the thermoelectric properties at high temperatures, the electrical conductivity and Seebeck coefficient were measured at temperatures between 423 K and 973 K for perovskite-type ceramics of BaBi1-xSbxO3 solid solutions with x=0.0-0.5. All the ceramics exhibit p-type semiconducting behaviors and electrical conduction is attributed to hopping of small polaronic holes localized on the pentavalent cations. Substitution of Bi with Sb causes the electrical conductivity σ and cell volume to decrease, but the Seebeck coefficient S to increase, suggesting that the Sb atoms are doped as Sb5+ and replace Bi5+, reducing 6s holes conduction from Bi5+(6s0) to Bi3+ (6s2). The thermoelectric power factor S2σ has values of 6×10-8-3×10-5 W m-1 K-2 in the measured temperature range, and is maximized for an Sb-undoped BaBiO3-δ, but decreases upon Sb doping due to the decreased σ values.

Optical study of phase transitions in single-crystalline RuP

NASA Astrophysics Data System (ADS)

Chen, R. Y.; Shi, Y. G.; Zheng, P.; Wang, L.; Dong, T.; Wang, N. L.

2015-03-01

RuP single crystals of MnP-type orthorhombic structure were synthesized by the Sn flux method. Temperature-dependent x-ray diffraction measurements reveal that the compound experiences two structural phase transitions, which are further confirmed by enormous anomalies shown in temperature-dependent resistivity and magnetic susceptibility. Particularly, the resistivity drops monotonically upon temperature cooling below the second transition, indicating that the material shows metallic behavior, in sharp contrast with the insulating ground state of polycrystalline samples. Optical conductivity measurements were also performed in order to unravel the mechanism of these two transitions. The measurement revealed a sudden reconstruction of band structure over a broad energy scale and a significant removal of conducting carriers below the first phase transition, while a charge-density-wave-like energy gap opens below the second phase transition.

Inadequate consultation behavior modulates the relationship between type D personality and impaired health status in chronic heart failure.

PubMed

Pelle, Aline J; Schiffer, Angélique A; Smith, Otto R; Widdershoven, Jos W; Denollet, Johan

2010-06-25

Psychological risk factors for impaired health outcomes have been acknowledged in chronic heart failure (CHF), with Type D personality being such a risk factor. Inadequate consultation behavior, a specific aspect of self-management, might be one mechanism in explaining the adverse effect of Type D on health outcomes. In this study we examined the relationship between Type D personality, impaired disease-specific health status, and inadequate consultation behavior. CHF outpatients (n=313) completed the Type D Scale (DS14) at baseline, and the European Heart Failure Self-care Behaviour Scale (EHFScBS) and the Minnesota Living with Heart Failure Questionnaire (MLWHFQ) at 6-month follow-up. Type D personality independently predicted inadequate consultation behavior (OR=1.80, 95%CI [1.03-3.16], p=.04) and impaired health status (OR=3.61, 95%CI [1.93-6.74], p<.001) at 6-month follow-up, adjusting for demographic and clinical variables. Inadequate consultation behavior (OR=1.80, 95%CI [1.11-2.94], p=.02) and NYHA-class (OR=2.83, 95%CI [1.17-4.71], p<.001) were associated with impaired health status, after controlling for demographics, clinical variables, and Type D personality. Post-hoc multivariable analysis pointed out that Type D patients who displayed inadequate consultation behavior were at a 6-fold increased risk of reporting impaired health status, compared to the reference group of non-Type D patients who displayed adequate consultation behavior (OR=6.06, 95%CI [2.53-14.52], p<.001). These findings provide evidence for inadequate behavior as a mechanism that may explain the link between Type D personality and impaired health status. Future studies are warranted to elaborate on these findings. Copyright 2008 Elsevier Ireland Ltd. All rights reserved.

Knowledge and Practice of Junior and Senior High School Students Regarding Violent Behaviors in Isfahan Province

PubMed Central

Omidi, Razieh; Heidari, Kamal; Ramezani, Arash; Amini, Maryam; Kamrooz, Shiva; Farajzadegan, Ziba; Pashmi, Rezvan; Fatemi, Seyyed Azim; Bagheri, Saeed; Salimi, Abolfazl; Babak, Anahita

2014-01-01

Background: Considering the importance of anger, aggression, violence and other misbehaviours in schoolchildren education, the present study was conducted to evaluate the knowledge and practice of students in Isfahan province regarding violence, in order to figure out the required interventions for violence-reduction. Methods: In a survey during 2008-2009, 5500 junior and senior high school students of Isfahan province were assessed in a multistage sampling process to determine their level of knowledge about various types of violent behaviors, causes of violence, its consequences, and preventive behaviors. Validity and reliability of the data collection tool (questionnaire) were assessed. Results: The study revealed that the mean scores of violent behaviors knowledge, knowledge of violent behavior outcomes, and knowledge of violence preventive behaviors, were 6.6 ± 2.1, 5.5 ± 1.9, and 4.7 ± 1.3, respectively. Sources of violent behaviors in 92% of urban students and 89% of rural students were personal reasons and family behaviors, and 85% of urban and 88% of rural students considered mass media and computer games blameworthy, and the differences were statistically significant in all cases (P < 0.0001). In terms of practice, overall, 69.7% of girls and 84.2% of boys had violent behaviors. Physical and verbal violence were 31.3% and 40.7%in girls, and 66% and 52.8% in boys, respectively (intersexes P values were P < 0.001 and P = 0.7 respectively, and intra-sex P value was P < 0.0001). Conclusions: Results showed that girls and city dwellers were more aware of recognizing violent behaviors, outcomes, and causes, compared with boys and villagers, and in terms of general practice, violence was observed among boys more than girls. Further complementary studies in this area seem required. PMID:26157562

Knowledge and Practice of Junior and Senior High School Students Regarding Violent Behaviors in Isfahan Province.

PubMed

Omidi, Razieh; Heidari, Kamal; Ramezani, Arash; Amini, Maryam; Kamrooz, Shiva; Farajzadegan, Ziba; Pashmi, Rezvan; Fatemi, Seyyed Azim; Bagheri, Saeed; Salimi, Abolfazl; Babak, Anahita

2014-12-01

Considering the importance of anger, aggression, violence and other misbehaviours in schoolchildren education, the present study was conducted to evaluate the knowledge and practice of students in Isfahan province regarding violence, in order to figure out the required interventions for violence-reduction. In a survey during 2008-2009, 5500 junior and senior high school students of Isfahan province were assessed in a multistage sampling process to determine their level of knowledge about various types of violent behaviors, causes of violence, its consequences, and preventive behaviors. Validity and reliability of the data collection tool (questionnaire) were assessed. The study revealed that the mean scores of violent behaviors knowledge, knowledge of violent behavior outcomes, and knowledge of violence preventive behaviors, were 6.6 ± 2.1, 5.5 ± 1.9, and 4.7 ± 1.3, respectively. Sources of violent behaviors in 92% of urban students and 89% of rural students were personal reasons and family behaviors, and 85% of urban and 88% of rural students considered mass media and computer games blameworthy, and the differences were statistically significant in all cases (P < 0.0001). In terms of practice, overall, 69.7% of girls and 84.2% of boys had violent behaviors. Physical and verbal violence were 31.3% and 40.7%in girls, and 66% and 52.8% in boys, respectively (intersexes P values were P < 0.001 and P = 0.7 respectively, and intra-sex P value was P < 0.0001). Results showed that girls and city dwellers were more aware of recognizing violent behaviors, outcomes, and causes, compared with boys and villagers, and in terms of general practice, violence was observed among boys more than girls. Further complementary studies in this area seem required.

An Exploration into Framing Effects and Information Preferences: Implications for the Design of Energy Feedback Interfaces

NASA Astrophysics Data System (ADS)

Taylor-Brown, Peter

A recent topic in the energy industry involves developing strategies to reduce the necessary peak production capacity of our future electricity infrastructure. One of these strategies is promoting behavioral change among individual energy consumers. An inherent problem with electricity consumption is that electricity is invisible, intangible, and abstract. Interfaces that provide people with useful feedback on their usage can help with understanding and reduction of consumption. These interfaces intend to empower individuals with ability to adopt less wasteful energy consumption behaviors. Skillful HCI design will include attention to informational preferences, and framing effects due to presentation choices. An online questionnaire was utilized to explore this domain, and the results identified design requirements for a home feedback interface. The final dataset contained responses from 36 male and 49 female United States residents. Cost () was perceived as the most useful metric and kW as the least useful. Respondent preference was expressed for lower levels of automation, which was not attributable to distrust of automation. Further, a test of framings effects showed a higher likelihood to change behavior to save 100 dollars per year than 2 per week (U=1248.5, p=0.001). A feedback interface design based on the questionnaire results was used in the second phase of the research. A 2x2x2 factorial design compared the effects of goal-type (specific vs. open-ended), metric-use ( vs. kWh), and visualization (graphical vs. text-only) on user experience, learning and behavior during a consumption reduction task. Results showed that goal-type affects the amount of diagnostic behavior conducted by participants (U=351.0, p=0.001). Goal-type and metric-use independently affect participant belief that they could reduce their consumption in their real home with the same feedback shown in the task, F(df=1,39)=24.77, p=0.001; F(df=1,39)=5.55, p=0.05. In addition, visualization affects perceived comfort sacrifice from changing behaviors to reduce consumption, F(df=1,39)=8.97, p=0.01.

Photoluminescence and photocatalytic properties of rhombohedral CuGaO2 nanoplates

PubMed Central

Shi, Linlin; Wang, Fei; Wang, Yunpeng; Wang, Dengkui; Zhao, Bin; Zhang, Ligong; Zhao, Dongxu; Shen, Dezhen

2016-01-01

Rhombohedral phase CuGaO2 nanoplates with a diameter of about 10 μm were synthesized via low temperature hydrothermal method. Room temperature and low temperature photoluminescence of the obtained CuGaO2 nanoplates were characterized. CuGaO2 nanoplates exhibited blue emission at room temperature and free exciton emission were appeared at low temperature. The blue emission is originated from defects such as Cu vacancies, which is the possible origin of p-type conductivity. The appearance of free exciton emission can demonstrate the direct bandgap transition behavior of CuGaO2 nanoplates. The as-prepared p-type CuGaO2 nanoplates were further decorated by n-type ZnO nanoparticles via calcination method to fabricate p-n junction nanocomposites. The nanocomposites exhibited enhanced photocatalytic activity which can be ascribed to the effective separation of photogenerated carriers by the internal electrostatic field in the p-n junction region, and the enhanced light absorption properties resulted from sub-bandgap absorption effect of p-n junction. This work has offered a new insight into the design of p-n junction devices using p-type CuGaO2 nanoplates. PMID:26887923

Non-polar p-type Zn0.94Mn0.05Na0.01O texture: Growth mechanism and codoping effect

NASA Astrophysics Data System (ADS)

Zhang, L. Q.; Lu, B.; Lu, Y. H.; Ye, Z. Z.; Lu, J. G.; Pan, X. H.; Huang, J. Y.

2013-02-01

The microstructure and crystal orientations of polycrystalline films crucially affect the properties and performance of the films. Controlling preferred orientations (PO) and related film morphology are necessary to obtain the desirable properties. In this paper, we demonstrate a rational and effective route toward the realization of non-polar p-type ZnO thin film with surface texture on quartz substrate through Mn-Na codoping. It is uncovered experimentally and theoretically that mono-doping of Mn creates opportunity to realize PO from polar (c-axis) to non-polar ((101¯0), (101¯1), and (112¯0)) changing. With Mn-Na codoping, an acute modulation of the growth behavior and electrical conductivity of the film have been revealed, leading to weak p-type non-polar Zn0.94Mn0.05Na0.01O (ZMNO) texture. The dominant mechanism for the non-polar self-texture in the current paper is deliberately elucidated as resulting from the interplane surface diffusion with the cooperative effect of impurity dopants. The ZMNO films exhibit p-type conduction with hole concentration of 9.51 × 1015-1.86 × 1017 cm-3 and enhanced room temperature (RT) ferromagnetism possessing a saturation magnetization (Ms) of 1.52 μB/Mn. The results have potential applications in development of non-polar optoelectronic devices such as lighting emitting diodes (LEDs).

Commuting behaviors and exposure to air pollution in Montreal, Canada.

PubMed

Miao, Qun; Bouchard, Michèle; Chen, Dongmei; Rosenberg, Mark W; Aronson, Kristan J

2015-03-01

Vehicular traffic is a major source of outdoor air pollution in urban areas, and studies have shown that air pollution is worse during hours of commuting to and from work and school. However, it is unclear to what extent different commuting behaviors are a source of air pollution compared to non-commuters, and if air pollution exposure actually differs by the mode of commuting. This study aimed to examine the relationships between commuting behaviors and air pollution exposure levels measured by urinary 1-OHP (1-hydroxypyrene), a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs). A cross-sectional study of 174 volunteers living in Montreal, 92 females and 82 males, aged 20 to 53 years was conducted in 2011. Each participant completed a questionnaire regarding demographic factors, commuting behaviors, home and workplace addresses, and potential sources of PAH exposure, and provided a complete first morning void urine sample for 1-OHP analysis. Multivariable general linear regression models were used to examine the relationships between different types of commuting and urinary 1-OHP levels. Compared to non-commuters, commuters traveling by foot or bicycle and by car or truck had a significantly higher urinary 1-OHP concentration in urine (p=0.01 for foot or bicycle vs. non-commuters; p=0.02 for car or truck vs. non-commuters); those traveling with public transportation and combinations of two or more types of modes tended to have an increased 1-OHP level in urine (p=0.06 for public transportation vs. non-commuters; p=0.05 for commuters with combinations of two or more types of modes vs. non-commuters). No significant difference in urinary 1-OHP variation was found by mode of commuting. This preliminary study suggests that despite the mode of commuting, all types of commuting during rush hours increase exposure to air pollution as measured by a sensitive PAH metabolite biomarker, and mode of commuting did not explain exposure variation. Copyright © 2014 Elsevier B.V. All rights reserved.

Effect of educational intervention based on the Health Belief Model on promoting self-care behaviors of type-2 diabetes patients.

PubMed

Shabibi, Parisa; Zavareh, Mohammad Sadegh Abedzadeh; Sayehmiri, Kourosh; Qorbani, Mostafa; Safari, Omid; Rastegarimehr, Babak; Mansourian, Morteza

2017-12-01

Diabetes is a chronic disease in which patients require lifelong self-care behaviors. The present study offset to determine the effect of educational intervention based on the Health Belief Model (HBM) on promoting self-care behaviors of type 2 diabetes patients in Ilam, Iran 2014. A quasi-experimental research was conducted based on HBM in which 70 type 2 diabetic patients from Ilam, western Iran in 2014 were selected by multi-stage random sampling. A self-designed questionnaire was used, and pre-test was administered, subsequently, the educational intervention sessions were provided in the form of presentation, questions and answers, group discussion, and practical demonstrations in four sessions over a period of one month. Two months after the intervention, the post-tests were administered. The data were analyzed via SPSS 20 applying independent samples t-test, paired samples t-test, and univariate and multivariate regressions at a significance level of less than 0.05. The mean scores of susceptibility, severity, perceived benefits and barriers, self-efficacy, and self-care behaviors were at average and lower levels before the intervention; nonetheless, after the educational intervention, the mean score of each HBM construct and the self-care behaviors significantly increased (p<0.001). Health education through HBM promotes the self-care behaviors of patients with type 2 diabetes.

Prediction of Physical Activity Level Using Processes of Change From the Transtheoretical Model: Experiential, Behavioral, or an Interaction Effect?

PubMed

Romain, Ahmed Jérôme; Horwath, Caroline; Bernard, Paquito

2018-01-01

The purpose of the present study was to compare prediction of physical activity (PA) by experiential or behavioral processes of change (POCs) or an interaction between both types of processes. A cross-sectional study. This study was conducted using an online questionnaire. A total of 394 participants (244 women, 150 men), with a mean age of 35.12 ± 12.04 years and a mean body mass index of 22.97 ± 4.25 kg/m 2 were included. Participants completed the Processes of Change, Stages of Change questionnaires, and the International Physical Activity Questionnaire to evaluate self-reported PA level (total, vigorous, and moderate PA). Hierarchical multiple regression models were used to test the prediction of PA level. For both total PA (β = .261; P < .001) and vigorous PA (β = .297; P < .001), only behavioral POCs were a significant predictor. Regarding moderate PA, only the interaction between experiential and behavioral POCs was a significant predictor (β = .123; P = .017). Our results provide confirmation that behavioral processes are most prominent in PA behavior. Nevertheless, it is of interest to note that the interaction between experiential and behavioral POCs was the only element predicting moderate PA level. Experiential processes were not associated with PA level.

Syndemic vulnerability, sexual and injection risk behaviors, and HIV continuum of care outcomes in HIV-positive injection drug users

PubMed Central

Mizuno, Yuko; Purcell, David W.; Knowlton, Amy R.; Wilkinson, James D.; Gourevitch, Marc N.; Knight, Kelly R.

2015-01-01

Limited investigations have been conducted on syndemics and HIV continuum of care outcomes. Using baseline data from a multi-site, randomized controlled study of HIV-positive injection drug users (n=1052), we examined whether psychosocial factors co-occurred, and whether these factors were additively associated with behavioral and HIV continuum of care outcomes. Experiencing one type of psychosocial problem was significantly (p<0.05) associated with an increased odds of experiencing another type of problem. Persons with 3 or more psychosocial problems were significantly more likely to report sexual and injection risk behaviors and were less likely to be adherent to HIV medications. Persons with 4 or more problems were less likely to be virally suppressed. Reporting any problems was associated with not currently taking HIV medications. Our findings highlight the association of syndemics not only with risk behaviors, but also with outcomes related to the continuum of care for HIV-positive persons. PMID:25249392

Community-based Diabetes Education for Latinos: The Diabetes Empowerment Education Program.

PubMed

Castillo, Amparo; Giachello, Aida; Bates, Robin; Concha, Jeannie; Ramirez, Vanessa; Sanchez, Carlos; Pinsker, Eve; Arrom, Jose

2010-01-01

The purpose of this study was to conduct a diabetes education program delivered by community health workers (CHWs) in community settings and to evaluate its effectiveness in improving glycemic control and self-management skills in Hispanics/Latinos with type 2 diabetes. Trained CHWs recruited Hispanic/Latino community residents with self-reported type 2 diabetes, implemented intervention in nonclinical locations, and collected data on diabetes knowledge, self-care behaviors, self-efficacy, depression, A1C, weight, and blood pressure. Classes applied participatory techniques and were delivered in 2-hour group sessions over 10 weeks. Two focus groups collected qualitative postintervention data. Seventy participants enrolled, and 47 completed pretest and posttest data. Improvements were significant for A1C (P = .001) and systolic blood pressure (P = .006). Other positive outcomes were diabetes knowledge, physical activity, spacing carbohydrates, following a healthy eating plan, and eating fruits and vegetables. Improved behaviors also included foot care, glucose self-monitoring, and medication adherence. Depressive symptoms showed a positive trend in intent-to-treat analysis (P = .07), but self-efficacy did not change significantly (P = .142). Qualitative information reported an increase in participants' perceived competence in self-care and a positive influence of CHWs in participants' compliance with the program. A diabetes self-management education program for Hispanics/Latinos led by CHWs can be implemented in community settings and may effectively improve behavioral skills and glycemic control.

Thermoelectric Properties in Fermi Level Tuned Topological Materials (Bi1-xSnx)2Te3

NASA Astrophysics Data System (ADS)

Lin, Chan-Chieh; Shon, Won Hyuk; Rathnam, Lydia; Rhyee, Jong-Soo

2018-03-01

We investigated the thermoelectric properties of Sn-doped (Bi1-xSnx)2Te3 (x = 0, 0.1, 0.3, 0.5, and 0.7%) compounds, which is known as topological insulators. Fermi level tuning by Sn-doping can be justified by the n- to p-type transition with increasing Sn-doping concentration, as confirmed by Seebeck coefficient and Hall coefficient. Near x = 0.3 and 0.5%, the Fermi level resides inside the bulk band gap, resulting in a low Seebeck coefficient and increase of electrical resistivity. The magnetoconductivity with applying magnetic field showed weak antilocalization (WAL) effect for pristine Bi2Te3 while Sn-doped compounds do not follow the WAL behavior of magneto-conductivity, implying that the topological surface Dirac band contribution in magneto-conductivity is suppressed with decreasing the Fermi level by Sn-doping. This research can be applied to the topological composite of p-type/n-type topological materials by Fermi level tuning via Sn-doping in Bi2Te3 compounds.

Few-layer 1T‧ MoTe2 as gapless semimetal with thickness dependent carrier transport

NASA Astrophysics Data System (ADS)

Song, Peng; Hsu, Chuanghan; Zhao, Meng; Zhao, Xiaoxu; Chang, Tay-Rong; Teng, Jinghua; Lin, Hsin; Loh, Kian Ping

2018-07-01

Semimetal MoTe2 can be a type II Weyl semimetal in the bulk, but monolayer of this material is predicted to be quantum spin hall insulators. This dramatic change in electronic properties with number of layers is an excellent example of the dimensional effects of quantum transport. However, a detailed experimental study of the carrier transport and band structure of ultrathin semimetal MoTe2 is lacking so far. We performed magneto-transport measurements to study the conduction behavior and quantum phase coherence of 1T‧ MoTe2 as a function of its thickness. We show that due to a unique two-band transport mechanism (synergetic contribution from electron conduction and hole conduction), the conduction behavior of 1T‧ MoTe2 changes from metallic to p-type unipolar, and finally to ambipolar as the thickness decreases, suggesting that this effect can be used in devices by effectively controlling the thickness. Our transport studies, optical measurements and first-principles electronic structure calculations reveal that 1T‧ MoTe2 remains gapless down to a few (~2–3) layers. Despite being gapless, 1T‧ MoTe2 exhibits metal-insulator transition at 3-layer thickness, due to enhanced carrier localization effect.

Radio frequency abnormal dielectric response of manganese chromite (MnCr{sub 2}O{sub 4}) nanoparticles synthesized by coprecipitation method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gul, Muhammad, E-mail: mgul@upesh.edu.pk

2016-04-15

Highlights: • Uniform MnCr{sub 2}O{sub 4} nanoparticles synthesized by surfactant-free coprecipitation route. • XRD analysis confirmed the single spinel phase formation in the material. • Dielectric loss was found abnormal over certain lower frequencies. • AC conductivity proved the involvement of small polarons in conduction process. - Abstract: Radio frequency dielectric behavior of nanocrystalline MnCr{sub 2}O{sub 4} synthesized via surfactant-free controlled coprecipitation route has been studied. Keeping in view the necessity of particle size uniformity and phase purity for genuine performance, experimental conditions were optimized accordingly. The scanning electron micrographs of the synthesized product revealed the formation of monodispersed particlemore » system. X-ray diffraction analysis confirmed monophasic spinel structure formation with 65 nm crystallite size. Two characteristic peaks observed between 700 cm{sup −1} and 400 cm{sup −1} in the FTIR spectrum also supported the spinel phase purity of compound. The dielectric constant was found normal, but loss tangent of the sample showed abnormal behavior with frequency. The observed dielectric behavior of the synthesized product has been explained on the basis of space-charge polarization according to Maxwell–Wagner’s model and mutual contribution of n-type &p-type charge carriers (Rezlescu model). The ac conductivity linearly increased with frequency highlighting the existence of polaron hopping.« less

Graphene oxide-zinc oxide nanocomposite as channel layer for field effect transistors: effect of ZnO loading on field effect transport.

PubMed

Jilani, S Mahaboob; Banerji, Pallab

2014-10-08

The effects of ZnO on graphene oxide (GO)-ZnO nanocomposites are investigated to tune the conductivity in GO under field effect regime. Zinc oxides with different concentrations from 5 wt % to 25 wt % are used in a GO matrix to increase the conductivity in the composite. Six sets of field effect transistors with pristine GO and GO-ZnO as the channel layer at varying ZnO concentrations were fabricated. From the transfer characteristics, it is observed that GO exhibited an insulating behavior and the transistors with low ZnO (5 wt %) concentration initially showed p-type conductivity that changes to n-type with increases in ZnO loading. This n-type dominance in conductivity is a consequence of the transfer of electrons from ZnO to the GO matrix. From X-ray photoelectron spectroscopic measurements, it is observed that the progressive reduction in the C-OH oxygen group took place with increases in ZnO loading. Thus, from insulating GO to p- and then n-type, conductivity in GO could be achieved with reduction in the C-OH oxygen group by photocatalytic reduction of GO with varying degrees of ZnO. The restoration of sp(2) electron network in the GO matrix with the anchoring of ZnO nanostructures was observed from Raman spectra. From UV-visible spectra, the band gap in pristine GO was found to be 3.98 eV and reduced to 2.8 eV with increase in ZnO attachment.

How localized acceptors limit p-type conductivity in GaN

NASA Astrophysics Data System (ADS)

Lyons, John L.

2013-03-01

Despite the impressive development of GaN as an optoelectronic material, p-type conductivity is still limited. Only a single acceptor impurity, magnesium, is known to lead to p-type GaN. But Mg is far from a well-behaved acceptor. Hydrogen is known to passivate Mg, necessitating a post-growth anneal for acceptor activation. In addition, the ionization energy is quite large (~ 200 meV in GaN), meaning only a few percent of Mg acceptors are ionized at room temperature. Thus, hole conductivity is limited, and high concentrations of Mg are required to achieve moderately p-type GaN. Other acceptor impurities have not proven to be effective p-type dopants, for reasons that are still unresolved. Using advanced first-principles calculations based on a hybrid functional, we investigate the electrical and optical properties of the isolated Mg acceptor and its complexes with hydrogen in GaN, InN, and AlN.[2] We employ a technique that overcomes the band-gap-problem of traditional density functional theory, and allows for quantitative predictions of acceptor ionization energies and optical transition energies. Our results allow us to explain the deep or shallow nature of the Mg acceptor and its relation to the optical signals observed in Mg-doped GaN. We also revisit the properties of other group-II acceptors in GaN. We find that all cation-site acceptors show behavior similar to MgGa, and lead to highly localized holes. The ZnGa and BeGa acceptors have ionization energies that are even larger than that of Mg, making them ineffective dopants. All acceptors cause large lattice distortions in their neutral charge state, in turn leading to deep, broad luminescence signals that can serve as a means of experimentally verifying the deep nature of these acceptors. This work was performed in collaboration with Audrius Alkauskas, Anderson Janotti, and Chris G. Van de Walle. It was supported by the NSF and by the Solid State Lighting and Energy Center at UCSB.

Impact of Health Literacy, Self-efficacy, and Outcome Expectations on Adherence to Self-care Behaviors in Iranians with Type 2 Diabetes

PubMed Central

Reisi, Mahnoush; Mostafavi, Firoozeh; Javadzade, Homamodin; Mahaki, Behzad; Tavassoli, Elahe; Sharifirad, Gholamreza

2016-01-01

Objectives Diabetic patients with higher health literacy (HL) may feel more confident in their ability to perform self-care behaviors and may have strong beliefs that diabetes-related behaviors will lead to specific outcomes. Our study aimed to document the relationships between HL, self-efficacy, outcome expectations, and diabetes self-care of patients with type 2 diabetes mellitus (T2DM) in Iran. Methods We conducted a cross-sectional observational study of 187 patients with T2DM. Participants completed the Functional Communicative and Critical Health Literacy scale, the Summary of Diabetes Self-Care Activities, the Diabetes Management Self-Efficacy Scale, Outcome Expectations Questionnaire, and a demographic questionnaire. Results Participants who received diabetes education (t = 5.79, p<0.001) and were married (F = 3.04, p<0.050) had better diabetes self-care behavior. There was a significant positive correlation between self-care behaviors and communicative HL (r = 0.455, p<0.010), critical HL (r = 0.297, p<0.010), self-efficacy (r = 0.512, p<0.010) and outcome expectations (r = 0.387, p<0.010). Diabetes education and marital status accounted for 16.9% of the variance in diabetes self-care. Self-efficacy, outcome expectations, communicative, and critical HL explained 28.0%, 1.5%, 3.7%, and 1.4% of the variance, respectively. Conclusions This study revealed that the potential impact of self-efficacy, outcome expectations, communicative, and critical HL should be considered in the education program for patients with diabetes. We found self-efficacy to be the most important predictor of diabetes self-care. Therefore, the use of self-efficacy theory when designing patient education interventions could enhance diabetes self-care. It is essential that health care providers assess patient’s HL levels to tailor health-related information specific to a domain of HL. This would fully inform patients and promote empowerment rather than simple compliance. PMID:26813680

Metamaterial Behavior of Polymer Nanocomposites Based on Polypropylene/Multi-Walled Carbon Nanotubes Fabricated by Means of Ultrasound-Assisted Extrusion

PubMed Central

Pérez-Medina, Juan C.; Waldo-Mendoza, Miguel A.; Cruz-Delgado, Víctor J.; Quiñones-Jurado, Zoe V.; González-Morones, Pablo; Ziolo, Ronald F.; Martínez-Colunga, Juan G.; Soriano-Corral, Florentino; Avila-Orta, Carlos A.

2016-01-01

Metamaterial behavior of polymer nanocomposites (NCs) based on isotactic polypropylene (iPP) and multi-walled carbon nanotubes (MWCNTs) was investigated based on the observation of a negative dielectric constant (ε′). It is demonstrated that as the dielectric constant switches from negative to positive, the plasma frequency (ωp) depends strongly on the ultrasound-assisted fabrication method, as well as on the melt flow index of the iPP. NCs were fabricated using ultrasound-assisted extrusion methods with 10 wt % loadings of MWCNTs in iPPs with different melt flow indices (MFI). AC electrical conductivity (σ(AC)) as a function of frequency was determined to complement the electrical classification of the NCs, which were previously designated as insulating (I), static-dissipative (SD), and conductive (C) materials. It was found that the SD and C materials can also be classified as metamaterials (M). This type of behavior emerges from the negative dielectric constant observed at low frequencies although, at certain frequencies, the dielectric constant becomes positive. Our method of fabrication allows for the preparation of metamaterials with tunable ωp. iPP pure samples show only positive dielectric constants. Electrical conductivity increases in all cases with the addition of MWCNTs with the largest increases observed for samples with the highest MFI. A relationship between MFI and the fabrication method, with respect to electrical properties, is reported. PMID:28774042

Ferroelectric-induced carrier modulation for ambipolar transition metal dichalcogenide transistors

NASA Astrophysics Data System (ADS)

Yin, Lei; Wang, Zhenxing; Wang, Feng; Xu, Kai; Cheng, Ruiqing; Wen, Yao; Li, Jie; He, Jun

2017-03-01

For multifarious electronic and optoelectronic applications, it is indispensable exploration of stable and simple method to modulate electrical behavior of transition metal dichalcogenides (TMDs). In this study, an effective method to adjust the electrical properties of ambipolar TMDs is developed by introducing the dipole electric field from poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) ferroelectric polymer. The transition from ambipolar to p-type conductive characteristics is realized, and the transistor performances are also significantly enhanced. Hole density of MoTe2- and WSe2-based back-gate field effect transistors increases by 4.4 and 2.5 times. Moreover, the corresponding hole mobilities are strikingly improved from 0.27 to 10.7 cm2 V-1 s-1 and from 1.6 to 59.8 cm2 V-1 s-1, respectively. After optimizing, p-channel MoTe2 phototransistors present ultrahigh responsivity of 3521 A/W, which is superior to most layered phototransistors. The remarkable control of conductive type, carrier concentration, and field-effect mobility of ambipolar TMDs via P(VDF-TrFE) treatment paves a way for realization of high-performance and versatile electronic and optoelectronic devices.

Scanning Probe Microscopy and Electrical Transport Studies of Ferroelectric Thin Films and 2D van der Waals Materials

NASA Astrophysics Data System (ADS)

Xiao, Zhiyong

In this dissertation, I present the scanning microscopy and electrical transport studies of ferroelectric thin films and ferroic/2D van der Waals heterostructures. Based on the conducting probe atomic force microscopy and piezo-response force microscopy (PFM) studies of the static and dynamic behavior of ferroelectric domain walls (DW), we found that the ferroelectric polymer poly(vinylidene-fluoride-trifluorethylene) P(VDF-TrFE) is composed of two-dimensional (2D) ferroelectric monolayers (MLs) that are weakly coupled to each other. We also observed polarization asymmetry in epitaxial thin films of ferroelectric Pb(Zr,Ti)O3, which is attributed to the screening properties of the underlying conducting oxide. PFM studies also reveal ferroelectric relaxor-type behavior in ultrathin Sr(Zr,Ti)O3 films epitaxially deposited on Ge. We exploited scanning-probe-controlled domain patterning in a P(VDF-TrFE) top layer to induce nonvolatile modulation of the conduction characteristic of ML molybdenum disulfide (MoS2) between a transistor and a junction state. In the presence of a DW, MoS2 exhibits rectified Ids-Vds (IV) characteristics that are well described by the thermionic emission model. This approach can be applied to a wide range of van der Waals materials to design various functional homojunctions and nanostructures. We also studied the interfacial charge transfer effect between graphene and magnetoelectric Cr2O3 via electrostatic force microscopy and Kelvin probe force microscopy, which reveal p-type doping with up to 150 meV shift of the Fermi level. The graphene/Cr2O3 heterostructure is promising for developing magnetoelectric graphene transistors for spintronic applications.

Establishing a model to assess the effects of school support and self-care behaviors on life satisfaction in adolescents with type 1 diabetes in Taiwan.

PubMed

Tang, Shan-Mei; Chen, Shu-Wen; Wang, Ruey-Hsia

2013-12-01

Life satisfaction is associated with positive development in adolescents. Understanding a path model of life satisfaction can help healthcare providers design interventions to improve positive development in adolescents with type 1 diabetes. The aim of this study was to construct a model that assesses the effects of school support and self-care behaviors on life satisfaction in adolescents with type 1 diabetes in Taiwan. This study used a cross-sectional design. One hundred and thirty-nine adolescents aged 10-18 years and diagnosed with type 1 diabetes were recruited. Participants completed questionnaires that assessed perceived school support, self-care behaviors, and life satisfaction. The hypothesized model was tested using structural equation modeling. School support significantly and directly affected self-care behaviors (β = .46, p = .022) and life satisfaction (β = .39, p = .034), self-care behaviors directly affected life satisfaction (β = .56, p = .048), and school support indirectly affected life satisfaction (β = .26, p = .015) through the mediation of self-care behaviors. The fix indices were as follows: χ2 = 8.141, df = 11, p = .701, goodness of fit index = .984, normed fit index = .949, and root mean square residual = .001. The model explained 66.1% of total life satisfaction variance. School support and self-care behaviors positively influence the life satisfaction of adolescents with type 1 diabetes. Improvements in school support and self-care behaviors are necessary to improve life satisfaction in this vulnerable group.

A p-Type Zinc-Based Metal-Organic Framework.

PubMed

Shang, Congcong; Gautier, Romain; Jiang, Tengfei; Faulques, Eric; Latouche, Camille; Paris, Michael; Cario, Laurent; Bujoli-Doeuff, Martine; Jobic, Stéphane

2017-06-05

An original concept for the property tuning of semiconductors is demonstrated by the synthesis of a p-type zinc oxide (ZnO)-like metal-organic framework (MOF), (ZnC 2 O 3 H 2 ) n , which can be regarded as a possible alternative for ZnO, a natural n-type semiconductor. When small oxygen-rich organic linkers are introduced to the Zn-O system, oxygen vacancies and a deep valence-band maximum, the two obstacles for generating p-type behavior in ZnO, are restrained and raised, respectively. Further studies of this material on the doping and photoluminescence behaviors confirm its resemblance to metal oxides (MOs). This result answers the challenges of generating p-type behavior in an n-type-like system. This concept reveals that a new category of hybrid materials, with an embedded continuous metal-oxygen network, lies between the MOs and MOFs. It provides concrete support for the development of p-type hybrid semiconductors in the near future and, more importantly, the enrichment of tuning possibilities in inorganic semiconductors.

Self-Care Behaviors and Glycemic Control in Low-Income Adults in México With Type 2 Diabetes Mellitus May Have Implications for Patients of Mexican Heritage Living in the United States.

PubMed

Compeán Ortiz, Lidia G; Del Ángel Pérez, Beatriz; Reséndiz González, Eunice; Piñones Martínez, Socorro; González Quirarte, Nora H; Berry, Diane C

2016-04-01

This study examined self-care behaviors and their relationship to glycemic control in low-income Mexican adults with type 2 diabetes in Southeastern Tamaulipas, México. A total of 135 patients were enrolled from 17 community health centers. The most frequent self-care behavior was medication management (80%), and the least frequent self-care behavior was self blood glucose monitoring (7%). All the patients demonstrated poor glycemic control, with glycated hemoglobin > 7%. Self-care behaviors were associated with fasting blood glucose (rs = .223, p = .005). Medication management was influenced by cognitive performance, F(1, 130) = 4.49, p = .036, and depression, F(1, 130) = 8.22, p = .005. Dietary behaviors were influenced by previous diabetes education, F(1, 130) = 6.73, p = .011. These findings indicate that education and cognitive behavioral interventions in Spanish for Mexican adults with type 2 diabetes are urgently needed. © The Author(s) 2015.

Why Women Sit: Determinants of Leisure Sitting Time for Working Women.

PubMed

Walsh, Shana M; Umstattd Meyer, M Renée; Stamatis, Andreas; Morgan, Grant B

2015-01-01

Sedentary behavior is associated with negative health consequences independent of physical activity levels. Evidence suggests the work environment promotes sedentary behavior regardless of sector, and that employees with occupations requiring longer sitting times differ only marginally in leisure sitting time from those with more active occupations. Because physical activity opportunities may be limited across many work settings, leisure sedentary time may be more easily replaced with physical activity. Understanding correlates of leisure sedentary behaviors could inform interventions, specifically for women who are among the least active in America. Female employees at two universities completed online surveys (n = 156; mean age, 45.12 [SD = 12.5]; mean BMI, 26.7 kg/m(2) [SD = 5.9]; mean work hours/week, 43.7 [SD = 9.4]). Bivariate correlations and two hierarchical regression analyses were conducted to examine personal and behavioral correlates of weekday and weekend leisure sitting time. Final regression models revealed that greater weekday leisure sitting time (R(2) = 0.307) was related with being older (p = .006), having fewer children (p = .001), self-reporting poorer health (p = .006), and greater weekend sitting time (p < .001). Greater weekend leisure sitting time (R(2) = 0.261) was related with greater work-related sitting time (p = .020) and greater weekday leisure sitting time (p < .001). Physical activity was not related with weekday or weekend leisure sitting time. The most prominent correlates of leisure sitting time were other types of sedentary behaviors. This suggests that sedentary time in one segment of life predicts time spent sitting in other areas of life. Future interventions should target decreasing sedentary behaviors during leisure time specifically, in addition to increasing physical activity behavior. Copyright © 2015 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Zinc Vacancy Formation and its Effect on the Conductivity of ZnO

NASA Astrophysics Data System (ADS)

Khan, Enamul; Weber, Marc; Langford, Steve; Dickinson, Tom

2010-03-01

Exposing single crystal ZnO to 193-nm ArF excimer laser radiation can produce metallic zinc nanoparticles along the surface. The particle production mechanism appears to involve interstitial-vacancy pair formation in the near-surface bulk. Conductivity measurements made with one probe inside the laser spot and the other outside show evidence for rectifying behavior. Positron annihilation spectroscopy confirms the presence of Zn vacancies. We suggest that Zn vacancies are a possible source of p-type behavior in irradiated ZnO. Quadrupole mass spectroscopy shows that both oxygen and zinc are emitted during irradiation. Electron-hole pair production has previously been invoked to account for particle desorption from ZnO during UV illumination. Our results suggest that preexisting and laser-generated defects play a critical role in particle desorption and Zn vacancy formation.

A systematic study of (NH4)2S passivation (22%, 10%, 5%, or 1%) on the interface properties of the Al2O3/In0.53Ga0.47As/InP system for n-type and p-type In0.53Ga0.47As epitaxial layers

NASA Astrophysics Data System (ADS)

O'Connor, É.; Brennan, B.; Djara, V.; Cherkaoui, K.; Monaghan, S.; Newcomb, S. B.; Contreras, R.; Milojevic, M.; Hughes, G.; Pemble, M. E.; Wallace, R. M.; Hurley, P. K.

2011-01-01

In this work, we present the results of an investigation into the effectiveness of varying ammonium sulphide (NH4)2S concentrations in the passivation of n-type and p-type In0.53Ga0.47As. Samples were degreased and immersed in aqueous (NH4)2S solutions of concentrations 22%, 10%, 5%, or 1% for 20 min at 295 K, immediately prior to atomic layer deposition of Al2O3. Multi-frequency capacitance-voltage (C-V) results on capacitor structures indicate that the lowest frequency dispersion over the bias range examined occurs for n-type and p-type devices treated with the 10%(NH4)2S solution. The deleterious effect on device behavior of increased ambient exposure time after removal from 10%(NH4)2S solution is also presented. Estimations of the interface state defect density (Dit) for the optimum 10%(NH4)2S passivated In0.53Ga0.47As devices extracted using an approximation to the conductance method, and also extracted using the temperature-modified high-low frequency C-V method, indicate that the same defect is present over n-type and p-type devices having an integrated Dit of ˜2.5×1012 cm-2 (±1×1012 cm-2) with the peak density positioned in the middle of the In0.53Ga0.47As band gap at approximately 0.37 eV (±0.03 eV) from the valence band edge. Both methods used for extracting Dit show very good agreement, providing evidence to support that the conductance method can be applied to devices incorporating high-k oxides on In0.53Ga0.47As.

Graphene in ohmic contact for both n-GaN and p-GaN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhong, Haijian; Liu, Zhenghui; Shi, Lin

The wrinkles of single layer graphene contacted with either n-GaN or p-GaN were found both forming ohmic contacts investigated by conductive atomic force microscopy. The local I–V results show that some of the graphene wrinkles act as high-conductive channels and exhibiting ohmic behaviors compared with the flat regions with Schottky characteristics. We have studied the effects of the graphene wrinkles using density-functional-theory calculations. It is found that the standing and folded wrinkles with zigzag or armchair directions have a tendency to decrease or increase the local work function, respectively, pushing the local Fermi level towards n- or p-type GaN andmore » thus improving the transport properties. These results can benefit recent topical researches and applications for graphene as electrode material integrated in various semiconductor devices.« less

Carrier-injection studies in GaN-based light-emitting-diodes

NASA Astrophysics Data System (ADS)

Nguyen, Dinh Chuong; Vaufrey, David; Leroux, Mathieu

2015-09-01

Although p-type GaN has been achieved by Mg doping, the low hole-mobility still remains a difficulty for GaN-based light-emitting diodes (LEDs). Due to the lack of field-dependent-velocity model for holes, in GaN-based LED simulations, the hole mobility is usually supposed to remain constant. However, as the p-GaN-layer conductivity is lower than the n-GaN-layer conductivity, a strong electric-field exists in the p-side of an LED when the applied voltage exceeds the LED's built-in voltage. Under the influence of this field, the mobilities of electrons and holes are expected to decrease. Based on a field-dependent-velocity model that is usually used for narrow-bandgap materials, an LED structure is modelled with three arbitrarily chosen hole saturation-velocities. The results show that a hole saturation-velocity lower than 4x106 cm/s can negatively affect the LED's behaviors.

[Therapeutic massage on behavioral disturbances of elderly patients with dementia].

PubMed

Barquilla Ávila, Carolina; Rodríguez-Mansilla, Juan

2015-12-01

To know the efficacy of therapeutic massage on behavioral disturbances of elderly patients with dementia. Literature review. The literature search was done in six scientific databases: PubMed, Cochrane Library Plus, PEDro, Dialnet, Scopus and CSIC, between 1983 and 2013. The search terms were "massage", "dementia", "therapy", "behavior disorders" and "Alzheimer". Of the 496 articles analyzed, 11 scientific articles have met the selection criteria. Inclusion criteria were: clinical trials, published in English or Spanish, which had analyzed the effects of massage therapy on altered behaviors in people with dementia. The variables were massage benefits, type of massage and massage lubricant. Their authors use different massage techniques (effleurage, pétrissage, pressures, frictions and kneading), obtain better conduct disorders (aggression, anxiety, agitation, and resistance to care) of elderly. The therapeutic massage can be a complementary treatment in the rehabilitation program for better behavior disorders. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Metal-like electrical conductivity in LaxSr2-xTiMoO6 oxides for high temperature thermoelectric power generation.

PubMed

Saxena, Mandvi; Maiti, Tanmoy

2017-05-09

Increasing electrical conductivity in oxides, which are inherently insulators, can be a potential route in developing oxide-based thermoelectric power generators with higher energy conversion efficiency. In the present work, environmentally friendly non-toxic double perovskite La x Sr 2-x TiMoO 6 (LSTM) ceramics were synthesized using a solid-state reaction route by optimizing the sintering temperature and atmosphere for high temperature thermoelectric applications. Rietveld refinement of XRD data confirmed a single-phase solid solution with a cubic structure in these double perovskites with the space-group Pm3[combining macron]m. SEM studies showed a highly dense microstructure in these ceramics. High electrical conductivity on the order of 10 5 S m -1 and large carrier concentration (∼10 22 cm -3 ) were obtained in these materials. The temperature-dependent electrical conductivity measurement showed that the LSTM ceramics exhibit a semiconductor to metal transition. Thermopower (S) measurements demonstrated the conductivity switching from a p-type to n-type behavior at higher temperature. A temperature dependent Seebeck coefficient was further explained using a model for coexistence of both types of charge carriers in these oxides. A conductivity mechanism of these double perovskites was found to be governed by a small polaron hopping model.

Kondo lattice heavy fermion behavior in CeRh2Ga2

NASA Astrophysics Data System (ADS)

Anand, V. K.; Adroja, D. T.; Bhattacharyya, A.; Klemke, B.; Lake, B.

2017-04-01

The physical properties of an intermetallic compound CeRh2Ga2 have been investigated by magnetic susceptibility χ (T) , isothermal magnetization M(H), heat capacity {{C}\\text{p}}(T) , electrical resistivity ρ (T) , thermal conductivity κ (T) and thermopower S(T) measurements. CeRh2Ga2 is found to crystallize with CaBe2Ge2-type primitive tetragonal structure (space group P4/nmm). No evidence of long range magnetic order is seen down to 1.8 K. The χ (T) data show paramagnetic behavior with an effective moment {μ\\text{eff}}≈ 2.5~{μ\\text{B}} /Ce indicating Ce3+ valence state of Ce ions. The ρ (T) data exhibit Kondo lattice behavior with a metallic ground state. The low-T {{C}\\text{p}}(T) data yield an enhanced Sommerfeld coefficient γ =130(2) mJ/mol K2 characterizing CeRh2Ga2 as a moderate heavy fermion system. The high-T {{C}\\text{p}}(T) and ρ (T) show an anomaly near 255 K, reflecting a phase transition. The κ (T) suggests phonon dominated thermal transport with considerably higher values of Lorenz number L(T) compared to the theoretical Sommerfeld value L 0.

A study on the swelling behavior of poly(acrylic acid) hydrogels obtained by electron beam crosslinking

NASA Astrophysics Data System (ADS)

Sheikh, N.; Jalili, L.; Anvari, F.

2010-06-01

Poly(acrylic acid) (PAA) hydrogels were prepared by using electron beam (EB) crosslinking of PAA homopolymer from its aqueous solutions. The swelling behavior of the hydrogels was studied as a function of the concentration of PAA solution, radiation dose, pH of the swelling medium and swelling time. Also the environmental pH effect on the water diffusion mode into hydrogels was investigated. These hydrogels clearly showed pH-sensitive swelling behavior with Fickian type of diffusion in the stomach-like pH medium (pH 1.3) and non-Fickian type in the intestine-like pH medium (pH 6.8).

I-V curve hysteresis induced by gate-free charging of GaAs nanowires' surface oxide

NASA Astrophysics Data System (ADS)

Alekseev, P. A.; Geydt, P.; Dunaevskiy, M. S.; Lähderanta, E.; Haggrén, T.; Kakko, J.-P.; Lipsanen, H.

2017-09-01

The control of nanowire-based device performance requires knowledge about the transport of charge carriers and its limiting factors. We present the experimental and modeled results of a study of electrical properties of GaAs nanowires (NWs), considering their native oxide cover. Measurements of individual vertical NWs were performed by conductive atomic force microscopy (C-AFM). Experimental C-AFM observations with numerical simulations revealed the complex resistive behavior of NWs. A hysteresis of current-voltage characteristics of the p-doped NWs as-grown on substrates with different types of doping was registered. The emergence of hysteresis was explained by the trapping of majority carriers in the surface oxide layer near the reverse-biased barriers under the source-drain current. It was found that the accumulation of charge increases the current for highly doped p+-NWs on n+-substrates, while for moderately doped p-NWs on p+-substrates, charge accumulation decreases the current due to blocking of the conductive channel of NWs.

Identification and design principles of low hole effective mass p-type transparent conducting oxides

PubMed Central

Hautier, Geoffroy; Miglio, Anna; Ceder, Gerbrand; Rignanese, Gian-Marco; Gonze, Xavier

2013-01-01

The development of high-performance transparent conducting oxides is critical to many technologies from transparent electronics to solar cells. Whereas n-type transparent conducting oxides are present in many devices, their p-type counterparts are not largely commercialized, as they exhibit much lower carrier mobilities due to the large hole effective masses of most oxides. Here we conduct a high-throughput computational search on thousands of binary and ternary oxides and identify several highly promising compounds displaying exceptionally low hole effective masses (up to an order of magnitude lower than state-of-the-art p-type transparent conducting oxides), as well as wide band gaps. In addition to the discovery of specific compounds, the chemical rationalization of our findings opens new directions, beyond current Cu-based chemistries, for the design and development of future p-type transparent conducting oxides. PMID:23939205

Anomalous surface potential behavior observed in InN by photoassisted Kelvin probe force microscopy

NASA Astrophysics Data System (ADS)

Sun, Xiaoxiao; Wei, Jiandong; Wang, Xinqiang; Wang, Ping; Li, Shunfeng; Waag, Andreas; Li, Mo; Zhang, Jian; Ge, Weikun; Shen, Bo

2017-05-01

Lattice-polarity dependence of InN surface photovoltage has been identified by an anomalous surface potential behavior observed via photoassisted Kelvin probe force microscopy. Upon above bandgap light illumination in the ambient atmosphere, the surface photovoltage of the In-polar InN shows a pronounced decrease, while that of the N-polar one keeps almost constant. Those different behaviors between N-polar and In-polar surfaces are attributed to a polarity-related surface reactivity, which is found not to be influenced by Mg-doping. These findings provide a simple and non-destructive approach to determine the lattice polarity and allow us to suggest that the In-polar InN, especially that with buried p-type conduction, should be chosen for sensing application.

Conduct Disorders: Are Boot Camps Effective?

ERIC Educational Resources Information Center

Jeter, LaVaughn V.

2010-01-01

Youth diagnosed with "conduct disorder" are often placed in programs using forced compliance and coercive control. One type of intervention used to treat conduct disorder is the boot camp. The basic idea is that disruptive behaviors can be corrected by strict behavioral regulation and an emphasis on skills training (Weis & Toolis 2009; Weis,…

High-fire-risk behavior in critical fire areas

Treesearch

William S. Folkman

1977-01-01

Observations of fire-related behavior of wildland visitors were made in three types of areas-wilderness, established campground, and built-up commercial and residential areas-within the San Bernardino National Forest, California. Interviews were conducted with all persons so observed. Types of fire-related behavior differed markedly from one area to another, as did the...

Thermoelectric properties of rare earth chalcogenides

NASA Technical Reports Server (NTRS)

Danielson, L. R.; Raag, V.; Wood, C.

1985-01-01

The rare earth chalcogenides are important thermoelectric materials due to their high melting points, self-doping capabilities, and low thermal conductivities. Lanthanum sulfides and lanthanum tellurides have been synthesized in quartz ampules, hot-pressed into samples, and measured. The n-type Seebeck coefficients, electrical resistivities, and power factors generally all increased as the temperature increased from 200 to 1000 C. The figure-of-merit for nonstoichiometric lanthanum telluride was 0.001/deg C at 1000 C, considerably higher than for silicon-germanium. Thermoelectric measurements were made for LaTe(2) and YbS(1.4), and p-type behavior was observed for these compounds from 300 to 1100 C.

Schottky diode behaviour with excellent photoresponse in NiO/FTO heterostructure

NASA Astrophysics Data System (ADS)

Saha, B.; Sarkar, K.; Bera, A.; Deb, K.; Thapa, R.

2017-10-01

Delocalization of charge carriers through formation of native defects in NiO, to achieve a good metal oxide hole transport layer was attemted in this work and thus a heterojunction of p-type NiO and n-type FTO have been prepared through sol-gel process on FTO coated glass substrate. The synthesis process was stimulated by imparting large number of OH- sites during nucleation of Ni(OH)2 on FTO, so that during oxidation through annealing Ni vacancies are introduced. The structural properties as observed from X-ray diffraction measurement indicate formation of well crystalline NiO nanoparticles. Uniform distribution of NiO nanoparticles has been observed in the images obtained from scanning electron microscope. The occurrence of p-type conductivity in the NiO film was stimulated through the formation of delocalized defect carriers originated from crystal defects like vacancies or interstitials in the lattice. Ni vacancy creates shallow levels with respect to the valance band maxima and they readily produce holes. Thus a native p-type conductivity of NiO originates from Ni vacancies. NiO was thus obtained as an auspicious hole transport medium, which creates an expedient heterojunction at the interface with FTO. Excellent rectifying behavior was observed in the electrical J-V plot obtained from the prepared heterojunction. The results are explained from the band energy diagram of the NiO/FTO heterojunction. Remarkable photoresponse has been observed in the reverse characteristics of the heterojunction caused by photon generated electron hole pairs.

Facile synthesis and photo electrochemical performance of SnSe thin films

NASA Astrophysics Data System (ADS)

Pusawale, S. N.; Jadhav, P. S.; Lokhande, C. D.

2018-05-01

Orthorhombic structured SnSe thin films are synthesized via SILAR (successive ionic layer adsorption and reaction) method on glass substrates. The structural properties of thin films are characterized by x-ray diffraction, scanning electron microscopy studies from which nanoparticles with an elongated shape and hydrophilic behavior are observed. UV -VIS absorption spectroscopy study showed the maximum absorption in the visible region with a direct band gap of 1.55 eV. The photo electrochemical study showed p-type electrical conductivity.

The interplay of seven subthreshold conductances controls the resting membrane potential and the oscillatory behavior of thalamocortical neurons

PubMed Central

Zagha, Edward; Mato, German; Rudy, Bernardo; Nadal, Marcela S.

2014-01-01

The signaling properties of thalamocortical (TC) neurons depend on the diversity of ion conductance mechanisms that underlie their rich membrane behavior at subthreshold potentials. Using patch-clamp recordings of TC neurons in brain slices from mice and a realistic conductance-based computational model, we characterized seven subthreshold ion currents of TC neurons and quantified their individual contributions to the total steady-state conductance at levels below tonic firing threshold. We then used the TC neuron model to show that the resting membrane potential results from the interplay of several inward and outward currents over a background provided by the potassium and sodium leak currents. The steady-state conductances of depolarizing Ih (hyperpolarization-activated cationic current), IT (low-threshold calcium current), and INaP (persistent sodium current) move the membrane potential away from the reversal potential of the leak conductances. This depolarization is counteracted in turn by the hyperpolarizing steady-state current of IA (fast transient A-type potassium current) and IKir (inwardly rectifying potassium current). Using the computational model, we have shown that single parameter variations compatible with physiological or pathological modulation promote burst firing periodicity. The balance between three amplifying variables (activation of IT, activation of INaP, and activation of IKir) and three recovering variables (inactivation of IT, activation of IA, and activation of Ih) determines the propensity, or lack thereof, of repetitive burst firing of TC neurons. We also have determined the specific roles that each of these variables have during the intrinsic oscillation. PMID:24760784

Laser diode with thermal conducting, current confining film

NASA Technical Reports Server (NTRS)

Hawrylo, Frank Z. (Inventor)

1980-01-01

A laser diode formed of a rectangular parallelopiped body of single crystalline semiconductor material includes regions of opposite conductivity type indium phosphide extending to opposite surfaces of the body. Within the body is a PN junction at which light can be generated. A stripe of a conductive material is on the surface of the body to which the P type region extends and forms an ohmic contact with the P type region. The stripe is spaced from the side surfaces of the body and extends to the end surfaces of the body. A film of germanium is on the portions of the surface of the P type region which is not covered by the conductive stripe. The germanium film serves to conduct heat from the body and forms a blocking junction with the P type region so as to confine the current through the body, across the light generating PN junction, away from the side surfaces of the body.

Behavioral and emotional problems in a Kuala Lumpur children's home.

PubMed

Abd Rahman, Fairuz Nazri; Mohd Daud, Tuti Iryani; Nik Jaafar, Nik Ruzyanei; Shah, Shamsul Azhar; Tan, Susan Mooi Koon; Wan Ismail, Wan Salwina

2013-08-01

There is a dearth of studies on behavioral and emotional problems in residential care children in Malaysia. This study describes the behavioral and emotional problems in a sample of children in a government residential care home and compares them with their classmates living with their birth parents. A comparative cross-sectional study was carried out where carers from both groups were asked to fill in the translated Bahasa Melayu version of the Child Behavior Check List. Forms for 53 residential care children and 61 classmates were completed. The residential care children had significantly higher scores on the rule-breaking (P < 0.001) and Diagnostic and Statistical Manual of Mental Disorders (DSM) conduct problem subscales (P < 0.001). Residential care children's age significantly correlated with DSM somatic problems (P = 0.03) and post-traumatic stress (P = 0.023). Duration of care was significantly positively correlated with rule-breaking (P = 0.008), DSM conduct problems (P = 0.018) and externalizing scores (P = 0.017). Abuse and neglect cases had higher anxiety and depression scores (P = 0.024). Number of reasons in care positively correlated with several subscales, including total behavioral problem score (P = 0.005). Logistic regression revealed the greater number of reasons for placement a child had was significantly associated with having externalizing scores in the clinical range (P = 0.016). However, after Bonferroni correction, only the initial findings regarding rule-breaking and DSM conduct problem scores remained significant. Challenges exist in managing residential care children in Malaysia, especially regarding externalizing behavior. More studies are required to describe the Malaysian scene. © 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.

A computational assessment of the electronic, thermoelectric, and defect properties of bournonite (CuPbSbS 3) and related substitutions

DOE PAGES

Faghaninia, Alireza; Yu, Guodong; Aydemir, Umut; ...

2017-02-08

Bournonite (CuPbSbS 3) is an earth-abundant mineral with potential thermoelectric applications. This material has a complex crystal structure (space group Pmn2 1 #31) and has previously been measured to exhibit a very low thermal conductivity (κ < 1 W m -1 K -1 at T ≥ 300 K). In this study, we employ high-throughput density functional theory calculations to investigate how the properties of the bournonite crystal structure change with elemental substitutions. Specifically, we compute the stability and electronic properties of 320 structures generated via substitutions {Na-K-Cu-Ag}{Si-Ge-Sn-Pb}{N-P-As-Sb-Bi}{O-S-Se-Te} in the ABCD 3 formula. We perform two types of transport calculations: themore » BoltzTraP model, which has been extensively tested, and a newer AMSET model that we have developed and which incorporates scattering effects. We discuss the differences in the model results, finding qualitative agreement except in the case of degenerate bands. Based on our calculations, we identify p-type CuPbSbSe 3 , CuSnSbSe 3 and CuPbAsSe 3 as potentially promising materials for further investigation. We additionally calculate the defect properties, finding that n-type behavior in bournonite and the selected materials is highly unlikely, and p-type behavior might be enhanced by employing Sb-poor synthesis conditions to prevent the formation of Sb Pb defects. Finally, we discuss the origins of various trends with chemical substitution, including the possible role of stereochemically active lone pair effects in stabilizing the bournonite structure and the effect of cation and anion selection on the calculated band gap.« less

Preparation and Characterization of Surface Photocatalytic Activity with NiO/TiO₂ Nanocomposite Structure.

PubMed

Chen, Jian-Zhi; Chen, Tai-Hong; Lai, Li-Wen; Li, Pei-Yu; Liu, Hua-Wen; Hong, Yi-You; Liu, Day-Shan

2015-07-13

This study achieved a nanocomposite structure of nickel oxide (NiO)/titanium dioxide (TiO₂) heterojunction on a TiO₂ film surface. The photocatalytic activity of this structure evaluated by decomposing methylene blue (MB) solution was strongly correlated to the conductive behavior of the NiO film. A p -type NiO film of high concentration in contact with the native n -type TiO₂ film, which resulted in a strong inner electrical field to effectively separate the photogenerated electron-hole pairs, exhibited a much better photocatalytic activity than the controlled TiO₂ film. In addition, the photocatalytic activity of the NiO/TiO₂ nanocomposite structure was enhanced as the thickness of the p -NiO film decreased, which was beneficial for the migration of the photogenerated carriers to the structural surface.

The electrical properties of n-ZnO/p-SnO heterojunction diodes

NASA Astrophysics Data System (ADS)

Javaid, K.; Xie, Y. F.; Luo, H.; Wang, M.; Zhang, H. L.; Gao, J. H.; Zhuge, F.; Liang, L. Y.; Cao, H. T.

2016-09-01

In the present work, n-type zinc oxide (ZnO) and p-type tin monoxide (SnO) based heterostructure diodes were fabricated on an indium-tin-oxide glass using the radio frequency magnetron sputtering technique. The prepared ZnO/SnO diodes exhibited a typical rectifying behavior, with a forward to reverse current ratio about 500 ± 5 at 2 V and turn on voltage around 1.6 V. The built-in voltage of the diode was extracted to be 0.5 V based on the capacitance-voltage (C-V) measurement. The valence and conduction band offsets were deliberated through the band energy diagram of ZnO/SnO heterojunction, as 1.08 eV and 0.41 eV, respectively. The potential barrier-dependent carrier transportation mechanism across the space charge region was also investigated.

[A study on syphilis and HSV-2 infection and related behaviors among female sex workers who take new types of drugs in Jiaozhou city].

PubMed

Li, Zheng; Li, Dongmin; Jiang, Zhenxia; Liu, Huixin; Wang, Ning

2014-10-01

To explore the prevalence of syphilis and HSV-2 among female sex workers (FSWs) who use new types of drugs in Jiaozhou city. Through convenient sampling, an anonymous questionnaire survey was conducted among female sex workers to collect demographic characteristics, new-type drugs abusing characteristics and related sexual behaviors from October to December, 2013. Blood specimens were drawn for serological tests of syphilis antibody and HSV-2 antibody. Urine specimens of the subjects surveyed were collected to test for methamphetamine. Differences in demographic characteristics, new-type drug abusing characteristics, and sexual behaviours between drug-abusing FSWs and non-drug-abusing FSWs were compared by t-test and χ(2)-test. A total of 460 FSWs were recruited in this study, and 105 FSWs admitted their drug abuse history. Among the 341 urine specimens confirmed to be methamphetamine positive, there were 3 FSWs claimed that they never abuse new-type drugs. The rate of new-type drug abuse was 23.5% (108/460). A total of 71.4% (75/105) of the new drug-abusing FSWs started using drugs under 25 years old. The main reasons for drug abuse were clients request (24, 22.9%), making more money (23, 21.9%) and companion temptations (22, 21.0%). Totally, 41.9% of them (44/105) took drugs with 4-5 persons, 32.4% (34/105) had sex with 2-3 men after taking drugs, and 60.2% of new-type drug-abusing FSWs (65/108) used condoms in the latest commercial intercourse, while only 7.4% FSWs (8/108) used condoms every time during their commercial sex activities in the recent month. Compared with FSWs having no drug abuse behavior, drug-abusing FSWs had higher single proportion (73.2% (79/108) vs 63.6% (224/352), χ(2) = 8.64, P < 0.05), lower condom use rate in the recent month (7.4% (8/108) vs 22.7% (80/352), χ(2) = 12.53, P < 0.01) and higher pregnancy rate in the recent 6 months (24.1% (26/108) vs 8.8% (31/352), χ(2) = 17.74, P < 0.01) and most of them come from the middle and high-level entertainmens (78.7% (85/108) vs 65.1% (229/352), χ(2) = 13.09, P < 0.01). Among the new-type drug-abusing FSWs, the prevalence rates of syphilis and HSV-2 were 12.0% (13/108) and 55.6% (60/108) , respectively. A total of 33 FSWs claimed that they were diagnosed with STDs in the recent year (30.6%) . The rates of syphilis(12.0% (13/108) vs 4.0% (14/352), χ(2) = 9.72, P < 0.01), HSV-2(55.6% (60/108) vs 39.2% (138/352), χ(2) = 9.01, P < 0.01) and diagnosed STDs (30.6% (33/108) vs 17.9% (63/352), χ(2) = 8.02, P < 0.01) among the drug-abusing FSWs were significantly higher than those of non-drug-abusing FSWs. There is a higher proportion of new-type drug abuse among the FSWs in Jiaozhou, with significantly higher prevalence rates of syphilis and HSV-2 infection, compared with non-new types of drug abusing FSWs. Prevalent risk sexual behaviors and ignorance of new-types drugs' harm were seen among them.

First-principles prediction of a promising p-type transparent conductive material CsGeCl3

NASA Astrophysics Data System (ADS)

Huang, Dan; Zhao, Yu-Jun; Ju, Zhi-Ping; Gan, Li-Yong; Chen, Xin-Man; Li, Chang-Sheng; Yao, Chun-mei; Guo, Jin

2014-04-01

Most reported p-type transparent conductive materials are Cu-based compounds such as CuAlO2 and CuCrO2. Here, we report that compounds based on ns2 cations with low binding energy can also possess high valence band maximum, which is crucial for the p-type doping according to the doping limit rules. In particular, CsGeCl3, a compound with valence band maximum from ns2 cations, is predicted as a promising p-type transparent conductive material by first-principles calculations. Our results show that the p-type defect Ge vacancy dominates its intrinsic defects with a shallow transition level, and the calculated hole effective masses are low in CsGeCl3.

An information-motivation-behavioral skills analysis of diet and exercise behavior in Puerto Ricans with diabetes.

PubMed

Osborn, Chandra Y; Rivet Amico, K; Fisher, William A; Egede, Leonard E; Fisher, Jeffrey D

2010-11-01

Frameworks are needed to inform diabetes self-care programs for diverse populations. We tested the Information-Motivation-Behavioral Skills (IMB) model in a sample of Puerto Ricans with Type 2 diabetes (N = 118). Structural equation models evaluated model fit and interrelations between IMB constructs. For diet behavior, information and motivation related to behavioral skills ( r = 0.19, p < .05 and r = 0.39, p < .01, respectively); behavioral skills related to behavior (r = 0.42, p < .01 and r = 0.32, p < .05); and behavior related to glycemic control (r = -0.26, p < .05). For exercise, personal motivation related to behavioral skills (r = 0.53, p < .001), and behavioral skills related to behavior (r = 0.45, p < .001). The IMB model could inform interventions targeting these behaviors in diabetes.

An Information—Motivation—Behavioral Skills Analysis of Diet and Exercise Behavior in Puerto Ricans with Diabetes

PubMed Central

Osborn, Chandra Y.; Amico, K. Rivet; Fisher, William A.; Egede, Leonard E.; Fisher, Jeffrey D.

2011-01-01

Frameworks are needed to inform diabetes self-care programs for diverse populations. We tested the Information-Motivation-Behavioral Skills (IMB) model among Puerto Ricans with Type 2 diabetes (N=118). Structural equation models evaluated model fit and interrelations among constructs. For diet behavior, information and motivation related to behavioral skills (r=0.19, p<0.05 and r=0.39, p<0.01, respectively); behavioral skills related to behavior (r=0.42, p<0.01 and r=0.32, p<0.05); and behavior was related to glycemic control (r=−0.26, p<0.05). For exercise, personal motivation related to behavioral skills (r=0.53, p<0.001), and behavioral skills related to behavior (r=0.45, p<0.001). The IMB model could inform interventions targeting these behaviors in diabetes. PMID:20453056

[Correlation between self-management behaviors and blood glucose control in patients with type 2 diabetes mellitus in community].

PubMed

Yu, Pingping; Xiao, Xiangcheng; Wang, Linyun; Wang, Lei

2013-04-01

To investigate the self-management behaviors of patients with type 2 diabetes mellitus (DM) in a community and to explore the relationship between self-management behaviors and the glycemic control. A total of 211 type 2 DM patients in a community were selected by stratified random sampling. Patients were grouped according to the scores of self-management behaviors. The fasting plasma glucose (FPG), 2 h postprandial plasma glucose (2hPG) and glycated hemoglobin (HbA1C) level were tested. The differences between groups and relationship between self-management behaviors and glycemic control were analyzed. Self-management behaviors of most patients were not effective, and 2hPG and HbA1C were affected by different levels of the self-management behaviors (P<0.05). The self-management behaviors were negatively related to FPG (r=-0.277, P=0.015), 2hPG (r=-0.453, P=0.001), and HbA1C (r=-0.435, P=0.001). Glycemic control of the patients whose course of disease was over 5 years was significantly different due to different self-management behaviors. FPG level of the patients was positively related to alimentary control. The 2hPG level of the patients was positively related to alimentary control, medication persistence, and blood glucose self-monitoring. The HbA1C level of the patients was positively related to alimentary control and medication persistence. The times the patients received DM education, the way to use insulin, and the disease course of the patients were important factors to affect self-management behaviors of type 2 DM in the community. Self-management behaviors of type 2 DM patients in the community are not effective. Satisfactory self-management behaviors, specially the control of 2hPG and HbA1C are beneficial to glycemic control. We can improve the self-management behaviors in type 2 DM patients by paying attention to the disease course, the treatment method, and the contents and effect of DM education.

[The effects of a diabetic educational program for coping with problem situation on self-efficacy, self care behaviors, coping and glycemic control in type 2 diabetic patients].

PubMed

Ko, Choun Hee; Gu, Mee Ock

2004-12-01

This study was conducted to develop and to test the effects of an educational program for coping with problem situations as a nursing intervention in the diabetic patient. A non-equivalent control group pretest-posttest design was used in this study. Data were collected from January to March, 2002. The subjects of the study consisted of 31 diabetic patients(experimental group: 17 patients, control group: 14 patients). The intervention of an educational program for coping with problem situations was applied to the experimental group for 4 weeks (total 8 hours). Data were collected before the educational program, immediately after and 1 months later and were analyzed with repeated measures ANOVA, t-test, and paired t-test. 1. There was a significant difference in self efficacy between the experimental and control groups (F=13.793, p=0.001). 2. There was a significant difference in self care behavior between the experimental and control groups (F=4.583, p=0.041). 3. There was a significant difference in coping behavior of the problem situation between the experimental and control groups (F=62.018, p=0.000). There was a significant difference according to experimental stages (F=4.546, p=0.015) and interaction between education and experimental stages (F=12.039, p=0.000). 4. There was a significant difference in glycemic control between the experimental and control groups (t=-3.112, p=0.004). These results support that a diabetic educational program for coping with problem situations is effective in promoting and maintaining self efficacy, self care behavior, problem coping behaviors and in improving glycemic control. Thus this program can be recommended as an effective nursing intervention of in-depth education for diabetic patient.

Analysis of psychological characteristics of obese children.

PubMed

Liu, L-F; Bian, Q-T; Zhai, J-G

2017-06-01

We conducted this study to analyze the psychological characteristics of obese children. We selected 60 cases of obese children as obesity group and according to 1:1 matching principle, we selected 60 normal weight children as the control group. We investigated and analyzed children's family behavior, mental health, temperament, self-consciousness and social adaptability. The proportion of children with adverse behavior in the obesity group was significantly higher than that in the control group (p < 0.05). In the psychological health assessment, we compared the emotional disorder, social adjustment disorder, bad habits and behavior disorder score of both groups, and the differences were statistically significant (p < 0.05). We compared the temperament dimension score of both groups in avoidance, emotional nature, distractibility and threshold of reaction; the differences were statistically significant (p < 0.05). The proportion of negative temperament types in the obesity group were significantly higher than that in the control group (p < 0.05). We compared the self-awareness levels of both groups with regards to body appearance and properties such as gregariousness, happiness, satisfaction and total scores of self-concept aspects; the differences were statistically significant (p < 0.05). The level of social adaptive ability of the obesity group was significantly lower than that of the control group (p < 0.05). Children that demonstrate bad family behavior and that have a temperament which makes them difficult to raise are important factors related to obesity. Obese children often have mental and behavioral disorders, aversion, high emotional nature, low distractibility and threshold of reaction, damaged self-awareness, low self-evaluation, are not gregarious, demonstrate unhappiness and satisfaction and have poor social adaptation ability. Obesity is a cause for social concern. We need to strengthen the mental health education of obesity and promote the healthy development of children both physically and mentally.

pH-induced inversion of water-in-oil emulsions to oil-in-water high internal phase emulsions (HIPEs) using core cross-linked star (CCS) polymer as interfacial stabilizer.

PubMed

Chen, Qijing; Deng, Xiaoyong; An, Zesheng

2014-06-01

A pH-responsive core cross-linked star (CCS) polymer containing poly(N,N-dimethylaminoethyl methacrylate) (PDMAEMA) arms was used as an interfacial stabilizer for emulsions containing toluene (80 v%) and water (20 v%). In the pH range of 12.1-9.3, ordinary water-in-oil emulsions were formed. Intermediate multiple emulsions of oil-in-water-in-oil and water-in-oil-in-water were formed at pH 8.6 and 7.5, respectively. Further lowering the pH resulted in the formation of gelled high internal phase emulsions of oil-in-water type in the pH range of 6.4-0.6. The emulsion behavior was correlated with interfacial tension, conductivity and configuration of the CCS polymer at different pH. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

p-Type and n-type doping of ZnSe: Effects of hydrogen incorporation

NASA Astrophysics Data System (ADS)

Fisher, P. A.; Ho, E.; House, J. L.; Petrich, G. S.; Kolodziejski, L. A.; Walker, J.; Johnson, N. M.

1995-05-01

The hydrogenation behavior of p- and n-type ZnSe grown on GaAs by gas source molecular beam epitaxy (GSMBE) is presented. Recent advances in p-type doping, using a radio frequency (RF) plasma source with nitrogen, have led to the successful fabrication of blue/green light emitters based on the (Zn,Mg)(S,Se) material system grown by molecular beam epitaxy (MBE). GSMBE replaces the high vapor pressure group VI elements with hydride gases which are amenable to regulation using precision mass flow controllers, and has the potential to deliver improved compositional control and reproducibility. We have found that the presence of hydrogen does not affect the electrical conductivity of ZnSe:Cl grown by GSMBE. In contrast, nitrogen-doped ZnSe is speculated to be electrically passivated by hydrogen for certain growth conditions as evidenced by: (1) coherent tracking of the hydrogen concentration with variations in the nitrogen concentration, which is measured by secondary ion mass spectrometry (SIMS), and (2) indications of high resistivity determined by capacitance-voltage ( C-V) measurements. Conventional and rapid thermal annealing (RTA) have been investigated to modify the degree of hydrogen passivation.

P-Type Transparent Cu-Alloyed ZnS Deposited at Room Temperature

DOE PAGES

Woods-Robinson, Rachel; Cooper, Jason K.; Xu, Xiaojie; ...

2016-03-16

All transparent conducting materials (TCMs) of technological practicality are n-type; the inferior conductivity of p-type TCMs has limited their adoption. Additionally, many relatively high-performing p-type TCMs require synthesis temperatures > 400 °C. Here, room-temperature pulsed laser deposition of copper-alloyed zinc sulfide (Cu x Zn 1- x S) thin films (0 ≤ x ≤ 0.75) is reported. For 0.09 ≤ x ≤ 0.35, Cu x Zn 1- x S has high p-type conductivity, up to 42 S cm -1 at x = 0.30, with an optical band gap tunable from ≈3.0–3.3 eV and transparency, averaged over the visible, of 50%–71% formore » 200–250 nm thick films. In this range, synchrotron X-ray and electron diffraction reveal a nanocrystalline ZnS structure. Secondary crystalline Cu y S phases are not observed, and at higher Cu concentrations, x > 0.45, films are amorphous and poorly conducting. Furthermore, within the TCM regime, the conductivity is temperature independent, indicating degenerate hole conduction. A decrease in lattice parameter with Cu content suggests that the hole conduction is due to substitutional incorporation of Cu onto Zn sites. This hole-conducting phase is embedded in a less conducting amorphous Cu y S, which dominates at higher Cu concentrations. Finally, the combination of high hole conductivity and optical transparency for the peak conductivity Cu x Zn 1- x S films is among the best reported to date for a room temperature deposited p-type TCM.« less

Refractory materials for high-temperature thermoelectric energy conversion

NASA Technical Reports Server (NTRS)

Wood, C.; Emin, D.

1983-01-01

Theoretical work of two decades ago adequately explained the transport behavior and effectively guided the development of thermoelectric materials of high conversion efficiencies of conventional semiconductors (e.g., SiGe alloys). The more significant contributions involved the estimation of optimum doping concentrations, the reduction of thermal conductivity by solid solution doping and the development of a variety of materials with ZT approx. 1 in the temperature range 300 K to 1200 K. ZT approx. 1 is not a theoretical limitation although, experimentally, values in excess of one were not achieved. Work has continued with emphasis on higher temperature energy conversion. A number of promising materials have been discovered in which it appears that ZT 1 is realizable. These materials are divided into two classes: (1) the rare-earth chalcogenides which behave as itinerant highly-degenerate n-type semiconductors at room-temperature, and (2) the boron-rich borides, which exhibit p-type small-polaronic hopping conductivity.

Voltage Sensor Inactivation in Potassium Channels

PubMed Central

Bähring, Robert; Barghaan, Jan; Westermeier, Regina; Wollberg, Jessica

2012-01-01

In voltage-gated potassium (Kv) channels membrane depolarization causes movement of a voltage sensor domain. This conformational change of the protein is transmitted to the pore domain and eventually leads to pore opening. However, the voltage sensor domain may interact with two distinct gates in the pore domain: the activation gate (A-gate), involving the cytoplasmic S6 bundle crossing, and the pore gate (P-gate), located externally in the selectivity filter. How the voltage sensor moves and how tightly it interacts with these two gates on its way to adopt a relaxed conformation when the membrane is depolarized may critically determine the mode of Kv channel inactivation. In certain Kv channels, voltage sensor movement leads to a tight interaction with the P-gate, which may cause conformational changes that render the selectivity filter non-conductive (“P/C-type inactivation”). Other Kv channels may preferably undergo inactivation from pre-open closed-states during voltage sensor movement, because the voltage sensor temporarily uncouples from the A-gate. For this behavior, known as “preferential” closed-state inactivation, we introduce the term “A/C-type inactivation”. Mechanistically, P/C- and A/C-type inactivation represent two forms of “voltage sensor inactivation.” PMID:22654758

Life-science research within US academic medical centers.

PubMed

Zinner, Darren E; Campbell, Eric G

2009-09-02

Besides the generic "basic" vs "applied" labels, little information is known about the types of life-science research conducted within academic medical centers (AMCs). To determine the relative proportion, characteristics, funding, and productivity of AMC faculty by the type of research they conduct. Mailed survey conducted in 2007 of 3080 life-science faculty at the 50 universities with medical schools that received the most funding from the National Institutes of Health in 2004. Response rate was 74%. Research faculty affiliated with a medical school or teaching hospital, representing 77% of respondents (n = 1663). Type of research (basic, translational, clinical trials, health services research/clinical epidemiology, multimode, other), total funding, industry funding, publications, professional activities, patenting behavior, and industry relationships. Among AMC research faculty, 33.6% exclusively conducted basic science research as principal investigators compared with translational researchers (9.1%), clinical trial investigators (7.1%), and health services researchers/clinical epidemiologists (9.0%). While principal investigators garnered a mean of $410,755 in total annual research funding, 22.1% of all AMC research faculty were unsponsored, a proportion that ranged from 11.5% for basic science researchers to 46.8% for health services researchers (P < .001). The average AMC faculty member received $33,417 in industry-sponsored funding, with most of this money concentrated among clinical trial ($110,869) and multimode ($59,916) principal investigators. Translational (61.3%), clinical trial (67.3%), and multimode (70.9%) researchers were significantly more likely than basic science researchers (41.9%) to report a relationship with industry and that these relationships contributed to their most important scientific work (P < .05 for all comparisons). The research function of AMCs is active and diverse, incorporating a substantial proportion of faculty who are conducting research and publishing without sponsorship.

Relaxation processes and conduction mechanism in bismuth ferrite lead titanate composites

NASA Astrophysics Data System (ADS)

Sahu, Truptimayee; Behera, Banarji

2018-02-01

In this study, samarium (Sm)-doped multiferroic composites of 0.8BiSmxFe1-xO3-0.2PbTiO3 where x = 0.05, 0.10, 0.15, and 0.20 were prepared via the conventional solid state reaction route. The electrical properties of these composites were analyzed using an impedance analyzer over a wide range of temperatures and frequencies (102-106 Hz). The impedance and modulus analyses confirmed the presence of both bulk and grain boundary effects in the materials. The temperature dependence of impedance and modulus spectrum indicated the negative temperature coefficient of resistance behavior. The dielectric relaxation exhibited non-Debye type behavior and it was temperature dependent. The relaxation time (τ) and DC conductivity followed an Arrhenius type behavior. The frequency-dependent AC conductivity obeyed Jonscher's power law. The correlated barrier hopping model was appropriate to understand the conduction mechanism in the composites considered.

On Ni/Au Alloyed Contacts to Mg-Doped GaN

NASA Astrophysics Data System (ADS)

Sarkar, Biplab; Reddy, Pramod; Klump, Andrew; Kaess, Felix; Rounds, Robert; Kirste, Ronny; Mita, Seiji; Kohn, Erhard; Collazo, Ramon; Sitar, Zlatko

2018-01-01

Ni/Au contacts to p-GaN were studied as a function of free hole concentration in GaN using planar transmission line measurement structures. All contacts showed a nonlinear behavior, which became stronger for lower doping concentrations. Electrical and structural analysis indicated that the current conduction between the contact and the p-GaN was through localized nano-sized clusters. Thus, the non-linear contact behavior can be well explained using the alloyed contact model. Two contributions to the contact resistance were identified: the spreading resistance in the semiconductor developed by the current crowding around the electrically active clusters, and diode-type behavior at the interface of the electrically active clusters with the semiconductor. Hence, the equivalent Ni/Au contact model consists of a diode and a resistor in series for each active cluster. The reduced barrier height observed in the measurements is thought to be generated by the extraction of Ga from the crystalline surface and localized formation of the Au:Ga phase. The alloyed contact analyses presented in this work are in good agreement with some of the commonly observed behavior of similar contacts described in the literature.

The Dilemma of Supporting Electrolytes for Electroorganic Synthesis: A Case Study on Kolbe Electrolysis.

PubMed

Stang, Carolin; Harnisch, Falk

2016-01-08

Remarkably, coulombic efficiency (CE, about 50 % at 1 Farad equivalent), and product composition resulting from aqueous Kolbe electrolysis are independent of reactor temperature and initial pH value. Although numerous studies on Kolbe electrolysis are available, the interrelations of different reaction parameters (e.g., acid concentration, pH, and especially electrolytic conductivity) are not addressed. A systematic analysis based on cyclic voltammetry reveals that solely the electrolytic conductivity impacts the current-voltage behavior. When using supporting electrolytes, not only their concentration, but also the type is decisive. We show that higher concentrations of KNO3 result in reduced CE and thus in significant increase in electric energy demand per converted molecule, whereas Na2 SO4 allows improved space-time yields. Pros and cons of adding supporting electrolytes are discussed in a final cost assessment. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Risk of Leaching in Soils Amended by Compost and Digestate from Municipal Solid Waste

PubMed Central

Tarquis, Ana M.; Cartagena, M. Carmen

2014-01-01

New European directives have proposed the direct application of compost and digestate produced from municipal solid wastes as organic matter sources in agricultural soils. Therefore information about phosphorus leaching from these residues when they are applied to the soil is increasingly important. Leaching experiments were conducted to determine the P mobility in compost and digestate mixtures, supplying equivalent amounts to 100 kg P ha−1 to three different types of soils. The tests were performed in accordance with CEN/TS 14405:2004 analyzing the maximum dissolved reactive P and the kinetic rate in the leachate. P biowaste fractionation indicated that digestate has a higher level of available P than compost has. In contrast, P losses in leaching experiments with soil-compost mixtures were higher than in soil-digestate mixtures. For both wastes, there was no correlation between dissolved reactive P lost and the water soluble P. The interaction between soil and biowaste, the long experimentation time, and the volume of leachate obtained caused the waste's wettability to become an influential parameter in P leaching behavior. The overall conclusion is that kinetic data analysis provides valuable information concerning the sorption mechanism that can be used for predicting the large-scale behavior of soil systems. PMID:25003139

High carrier concentration p-type transparent conducting oxide films

DOEpatents

Yan, Yanfa; Zhang, Shengbai

2005-06-21

A p-type transparent conducting oxide film is provided which is consisting essentially of, the transparent conducting oxide and a molecular doping source, the oxide and doping source grown under conditions sufficient to deliver the doping source intact onto the oxide.

Relations of Behavioral Autonomy to Health Outcomes Among Emerging Adults With and Without Type 1 Diabetes

PubMed Central

Reynolds, Kerry A.; Becker, Dorothy; Escobar, Oscar; Siminerio, Linda

2014-01-01

Objective To examine the relation of behavioral autonomy to psychological, behavioral, and physical health among emerging adults with and without type 1 diabetes. Methods High school seniors with (n = 118) and without type 1 diabetes (n = 122) completed online questionnaires for three consecutive years. Behavioral autonomy, psychological health, risk behaviors, and diabetes outcomes were assessed. Regression analyses were conducted to predict Time 2 and 3 outcomes, controlling for Time 1 outcomes. Results There were no group differences in behavioral autonomy. Behavioral autonomy predicted better psychological health but only for emerging adults without diabetes. Behavioral autonomy was related to increased risk behavior for both groups. Behavioral autonomy was unrelated to self-care but predicted better glycemic control for females. Conclusions Behavioral autonomy may be beneficial for psychological health, but is related to increased risk behavior. The implications of behavioral autonomy for emerging adults with type 1 diabetes require careful consideration. PMID:25157070

[The relationship between reactive/proactive aggression, callous/unemotional traits and behavioural problems in Hungarian adolescents].

PubMed

Bozsik, Csilla; Körmendi, Attila; Inántsy-Pap, Judit; Pataky, Nóra; Gádoros, Júlia; Halász, József

2013-01-01

The relationship between the type of physical aggressive behavior, callous/unemotional traits and behavioral problems was extensively studied in the literature, but no similar data exist in Hungarian adolescents. In the present study, the type of aggressive behavior was assessed in adolescents on a normative sample to study its relationship with callous/unemotional traits and behavioral problems. 223 students were participated in the study after informed consent (girls, n=106, age: 14.2±1.5 years; boys, n=117, age: 13.9±1.6 years) from primary and secondary schools in Miskolc and adjacent areas. The Reactive/Proactive Aggression Questionnaire was used to assess the level of aggressive behavior, the Inventory of Callous Unemotional Traits was used to measure callous/unemotional traits, while behavioral problems were established by the means of the Strengths and Difficulties Questionnaire. In the present non-clinical sample, the level of reactive aggression was higher than the level of proactive aggressive behavior. In boys, proactive and total aggression measures were significantly higher compared to girls. In both genders, reactive aggression was specifically associated with emotional and peer-related problems. Proactive aggression was correlated positively with callous traits in both genders, while self-reported prosocial behavior had an inverse correlation with proactive aggressive behavior in boys. Self reported conduct- and hyperactivity problems were positively correlated with both types of aggressive behavior in both genders. The strongest positive correlation was observed between self-reported conduct symptoms and both types of aggressive behavior. Callous/unemotional traits were related with proactive forms of aggression, similar to literature data. Reactive aggressive behavior was related to peer-related and emotional problems, thus our data outlined the importance of the distinction between the two main types of aggression.

Optimizing the Mobilization of Wireless Communications Systems for Disaster Response Efforts

DTIC Science & Technology

2015-09-01

influencing behavior, about breaking old habits and attitudes, and about creating an environment that is conductive to embracing the new” (Kane, 2005, p...influencing behavior, about breaking old habits and attitudes, and about creating an environment that is conductive to embracing the new” (Kane, 2005, p...MacKinnon Second Reader: John Gibson THIS PAGE INTENTIONALLY LEFT BLANK i REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public

Multiple doping of silicon-germanium alloys for thermoelectric applications

NASA Technical Reports Server (NTRS)

Fleurial, Jean-Pierre; Vining, Cronin B.; Borshchevsky, Alex

1989-01-01

It is shown that heavy doping of n-type Si/Ge alloys with phosphorus and arsenic (V-V doping interaction) by diffusion leads to a significant enhancement of their carrier concentration and possible improvement of the thermoelectric figure of merit. High carrier concentrations were achieved by arsenic doping alone, but for a same doping level higher carrier mobilities and lower resistivities are obtained through phosphorus doping. By combining the two dopants with the proper diffusion treatments, it was possible to optimize the different properties, obtaining high carrier concentration, good carrier mobility and low electrical resistivity. Similar experiments, using the III-V doping interaction, were conducted on boron-doped p-type samples and showed the possibility of overcompensating the samples by diffusing arsenic, in order to get n-type behavior.

Facile synthesis of bismuth oxyhalide nanosheet films with distinct conduction type and photo-induced charge carrier behavior

NASA Astrophysics Data System (ADS)

Jia, Huimin; He, Weiwei; Zhang, Beibei; Yao, Lei; Yang, Xiaokai; Zheng, Zhi

2018-05-01

A modified successive ionic layer adsorption and reaction (SILAR) method was developed to fabricate 2D ordered BiOX (X = CI, Br, I) nanosheet array films on FTO substrates at room temperature. The formation of BiOX films were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), UV-vis absorption spectroscopy, and X-ray photoelectron spectroscopy (XPS). The semiconductor surface states determine the type of semiconductor. Although BiOCI, BiOBr and BiOI belong to the bismuth oxyhalide semiconductor family and possess similar crystal and electronic structures, they show different conductivity types due to their respective surface states. Mott-Schottky curve results demonstrate that the BiOCl and BiOI nanosheet arrays display n-type semiconductor properties, while the BiOBr films exhibit p-type semiconductor properties. Assisted by surface photovoltage (SPV) and transient photovoltage (TPV) techniques, the photoinduced charge transfer dynamics on the surface/interface of the BiOX/FTO nanosheet films were systematically and comparatively investigated. As revealed by the results, both the separation and transfer dynamics of the photo-induced carrier are influenced by film thickness.

Type A Behaviors, Hostility, Anger and Exercise Adherence.

ERIC Educational Resources Information Center

Goffaux, Jacqueline; And Others

A study was conducted to examine the relationship between the components of the Type A behavior pattern and the maintenance of exercise participation in a 5-month physical fitness program. Metropolitan Government employees (N=200) volunteered to participate in a pilot health promotion program. Physical fitness activities (supervised walking,…

Phosphorous doped p-type MoS2 polycrystalline thin films via direct sulfurization of Mo film

NASA Astrophysics Data System (ADS)

Momose, Tomohiro; Nakamura, Atsushi; Daniel, Moraru; Shimomura, Masaru

2018-02-01

We report on the successful synthesis of a p-type, substitutional doping at S-site, MoS2 thin film using Phosphorous (P) as the dopant. MoS2 thin films were directly sulfurized for molybdenum films by chemical vapor deposition technique. Undoped MoS2 film showed n-type behavior and P doped samples showed p-type behavior by Hall-effect measurements in a van der Pauw (vdP) configuration of 10×10 mm2 area samples and showed ohmic behavior between the silver paste contacts. The donor and the acceptor concentration were detected to be ˜2.6×1015 cm-3 and ˜1.0×1019 cm-3, respectively. Hall-effect mobility was 61.7 cm2V-1s-1 for undoped and varied in the range of 15.5 ˜ 0.5 cm2V-1s-1 with P supply rate. However, the performance of field-effect transistors (FETs) declined by double Schottky barrier contacts where the region between Ni electrodes on the source/drain contact and the MoS2 back-gate cannot be depleted and behaves as a 3D material when used in transistor geometry, resulting in poor on/off ratio. Nevertheless, the FETs exhibit hole transport and the field-effect mobility showed values as high as the Hall-effect mobility, 76 cm2V-1s-1 in undoped MoS2 with p-type behavior and 43 cm2V-1s-1 for MoS2:P. Our findings provide important insights into the doping constraints for transition metal dichalcogenides.

Chronotype-related differences in childhood and adolescent aggression and antisocial behavior--a review of the literature.

PubMed

Schlarb, Angelika A; Sopp, Roxanne; Ambiel, David; Grünwald, Julia

2014-02-01

Eveningness has been found to negatively affect adolescents' sleep and daytime functioning. Furthermore, eveningness is associated with greater impulsivity than morningness. Externalizing behavior could be chronotype-related, implying that the alteration of the circadian rhythm itself is connected to aspects of emotion and emotion regulation. The present study investigated chronotype-related differences in emotional and behavioral problems, especially aggression and antisocial behavior in children and adolescents. We conducted a comprehensive search via web of knowledge (MEDLINE, web of science), EBSCO, Ovid, PubMed, Google Scholar and PsycINDEX using the keywords: chronotype, chronobiology, morningness, eveningness, owls and larks as well as diurnal preference to fully capture every aspect of chronotype. For aggression we used the search terms: aggression, anger, hostility, violence, anti-social behavior, conduct disorder, oppositional defiant disorder, delinquency, social adjustment and externalizing behavior. N = 13 studies were included concerning chronotype, childhood, adolescence and antisocial behavior. Results showed that children and adolescents being E-types were more affected by daytime impairments. Additionally, behavioral and emotional problems as aggression or antisocial behavior were more pronounced in E- than in M-types. Our findings support an association of eveningness and the impact of aggression on children and adolescents. Longitudinal investigations should be conducted in order to insure causality of the effects in question. In addition, the elevated vulnerability toward aggression in evening types demonstrates the need for prevention and intervention programs that educate youths in proper sleep hygiene and evoke an awareness of the consequences of a habitually diminished sleep quality.

Chemical systems for improved oil recovery: Phase behavior, oil recovery, and mobility control studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Llave, F.; Gall, B.; Gao, H., Scott, L., Cook, I.

Selected surfactant systems containing a series of ethoxylated nonionic surfactants in combination with an anionic surfactant system have been studied to evaluate phase behavior as well as oil recovery potential. These experiments were conducted to evaluate possible improved phase behavior and overall oil recovery potential of mixed surfactant systems over a broad range of conditions. Both polyacrylamide polymers and Xanthan biopolymers were evaluated. Studies were initiated to use a chemical flooding simulation program, UTCHEM, to simulate oil recovery for laboratory and field applications and evaluate its use to simulate oil saturation distributions obtained in CT-monitoring of oil recovery experiments. Themore » phase behavior studies focused on evaluating the effect of anionic-nonionic surfactant proportion on overall phase behavior. Two distinct transition behaviors were observed, depending on the dominant surfactant in the overall system. The first type of transition corresponded to more conventional behavior attributed to nonionic-dominant surfactant systems. This behavior is manifested by an oil-water-surfactant system that inverts from a water-external (highly conducting) microemulsion to an oil-external (nonconducting) one, as a function of temperature. The latter type which inverts in an opposite manner can be attributed to the separation of the anionic-nonionic mixtures into water- and oil-soluble surfactants. Both types of transition behavior can still be used to identify relative proximity to optimal areas. Determining these transition ranges provided more insight on how the behavior of these surfactant mixtures was affected by altering component proportions. Efforts to optimize the chemical system for oil displacement experiments were also undertaken. Phase behavior studies with systems formulated with biopolymer in solution were conducted.« less

Children's Exposure to Violence: The Underlying Effect of Posttraumatic Stress Symptoms on Behavior Problems.

PubMed

Yoon, Susan; Steigerwald, Stacey; Holmes, Megan R; Perzynski, Adam T

2016-02-01

In this study we investigated whether witnessing violence and violence victimization were associated with children's internalizing and externalizing behavior problems and examined the mediating role of posttraumatic stress (PTS) symptoms in these relationships. Secondary data analysis was conducted using 3 waves of data from the National Survey of Child and Adolescent Well-Being. Path analyses were conducted to test direct and indirect effects of violence exposure on behavior problems, using 2,064 children (ages 8-15 years) reported to Child Protective Services for maltreatment. Being a victim of violence in the home was directly associated with more internalizing (β = .06, p = .007) and externalizing behavior problems (β = .07, p = .002), whereas witnessing violence was not directly related to either internalizing (β = .04, p = .056) or externalizing behavior problems (β = .03, p = .130). PTS symptoms mediated the effects of witnessing violence and violence victimization on internalizing behavior problems (β = .02, p = .002). Our findings suggest that PTS symptoms may be a mechanism underlying the association between violence exposure and internalizing behavior problems (R(2) = .23), underscoring the potential importance of assessing PTS symptoms and providing targeted trauma-focused interventions for children exposed to violence at home. Copyright © 2016 International Society for Traumatic Stress Studies.

Characterization of p-Type CdTe Electrodes in Acetonitrile/Electrolyte Solutions. Nearly Ideal Behavior from Reductive Surface Pretreatments.

DTIC Science & Technology

1983-06-30

using Ag conductive palnt and the entire assembly was mounted in glass tubing with ordinary epoxy leaving only the front crystal face, ...energy set, several eV higher than either Te2- or Teo (as measured for sputtered CdTe and Te, respectively) is assigned to TeO2 , the lowest stable...binding energy reported for TeO2 (575.9 eV). 33 The lower binding energy set of bands, lying midway between Teo and Te2 - , results from both Teo and

Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system.

PubMed

Tachi, Fuyuki; Osakabe, Masahiro

2012-12-01

Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites (Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite (Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species (T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

Vulnerability and behavioral response to ultraviolet radiation in the components of a foliar mite prey-predator system

NASA Astrophysics Data System (ADS)

Tachi, Fuyuki; Osakabe, Masahiro

2012-12-01

Ambient ultraviolet-B (UVB) radiation impacts plant-dwelling arthropods including herbivorous and predatory mites. However, the effects of UVB on prey-predator systems, such as that between the herbivorous spider mite and predatory phytoseiid mite, are poorly understood. A comparative study was conducted to determine the vulnerability and behavioral responses of these mites to ultraviolet (UV) radiation. First, we analyzed dose-response (cumulative irradiance-mortality) curves for the eggs of phytoseiid mites ( Neoseiulus californicus, Neoseiulus womersleyi, and Phytoseiulus persimilis) and the spider mite ( Tetranychus urticae) to UVB radiation from a UV lamp. This indicated that the phytoseiid mites were more vulnerable than the spider mite, although P. persimilis was slightly more tolerant than the other two phytoseiid mites. Second, we compared the avoidance behavior of adult female N. californicus and two spider mite species ( T. urticae, a lower leaf surface user; Panonychus citri, an upper leaf surface user) in response to solar UV and visible light. N. californicus actively avoided both types of radiation, whereas P. citri showed only minimal avoidance behavior. T. urticae actively avoided UV as well as N. californicus but exhibited a slow response to visible light as well as P. citri. Such variation in vulnerability and avoidance behavior accounts for differences in the species adaptations to solar UVB radiation. This may be the primary factor determining habitat use among these mites on host plant leaves, subsequently affecting accessibility by predators and also intraguild competition.

Characterization of silicon heterojunctions for solar cells

PubMed Central

2011-01-01

Conductive-probe atomic force microscopy (CP-AFM) measurements reveal the existence of a conductive channel at the interface between p-type hydrogenated amorphous silicon (a-Si:H) and n-type crystalline silicon (c-Si) as well as at the interface between n-type a-Si:H and p-type c-Si. This is in good agreement with planar conductance measurements that show a large interface conductance. It is demonstrated that these features are related to the existence of a strong inversion layer of holes at the c-Si surface of (p) a-Si:H/(n) c-Si structures, and to a strong inversion layer of electrons at the c-Si surface of (n) a-Si:H/(p) c-Si heterojunctions. These are intimately related to the band offsets, which allows us to determine these parameters with good precision. PMID:21711658

Effect of Precede-Proceed Model on Preventive Behaviors for Type 2 Diabetes Mellitus in High-Risk Individuals.

PubMed

Moshki, Mahdi; Dehnoalian, Atefeh; Alami, Ali

2017-04-01

This study sought to assess the effect of precede-proceed model on preventive behaviors for type 2 diabetes mellitus (DM) in high-risk individuals. In this semi-experimental study, 164 high-risk individuals for type 2 DM were selected and were randomly divided into two groups of intervention and control ( n = 85). Educational intervention was performed as a single session face-to-face instruction for 1.5 hr for the intervention group participants. Data were collected before (baseline) and immediately and 1 month after the intervention in the two groups. The mean score of predisposing (knowledge) factors ( p = .001), reinforcing factors ( p = .001), and enabling factors ( p = .02) were significantly different at baseline and 1 month after the intervention in the intervention group compared with the control group ( p < .05). A significant improvement occurred in the nutritional habits of high-risk participants in the intervention group at 1 month after the intervention compared with controls ( p = .001). The precede-proceed model can be effective for promoting the preventive behaviors for type 2 DM in high-risk individuals.

A general population twin study of conduct problems and the auditory P300 waveform.

PubMed

Bertoletti, Eleonora; Michelini, Giorgia; Moruzzi, Sara; Ferrer, Giuseppina; Ferini-Strambi, Luigi; Stazi, Maria Antonietta; Ogliari, Anna; Battaglia, Marco

2014-01-01

Reduced amplitude of the P300 event-related potential has been consistently associated with a variety of externalising problems, including conduct disorder. The few available genetically-informative studies of these relationships, however, were conducted among adolescents/adults (i.e., at an age when conduct disorder has typically already become manifest). Among 200 general population twins with a mean age of 9 years (range 6-14 years), we studied the relationship between the P300 waveform elicited by an auditory oddball task and the DSM-oriented conduct problems scale of the Child Behavior Checklist 6-18. Conduct problems scores were negatively and significantly correlated (r = -0.19, p = 0.01) with P300 amplitude; correlations between P300 amplitude and the other DSM-oriented Child Behavior Checklist scales were non-significant, except for oppositional defiant problems (p = 0.01). We found moderate heritability estimates for both P300 amplitude (0.58, CI:0.37;0.73) and conduct problems (0.52, CI:0.25;0.70). Bivariate twin analyses indicated that the covariation between these two phenotypes can be explained by additive genetic factors only, with a genetic correlation of -0.33. An association between reduced P300 amplitude and conduct problems can be substantiated already in childhood, at an age that precedes the most typical onset of conduct disorder. This relationship appears to be genetic in nature. Reduced P300 amplitude can represent a valuable marker for conduct problems, and can contribute to the early identification of children at high-risk for conduct disorder.

The effects of a pedometer-based behavioral modification program with telephone support on physical activity and sedentary behavior in type 2 diabetes patients.

PubMed

De Greef, Karlijn P; Deforche, Benedicte I; Ruige, Johannes B; Bouckaert, Jacques J; Tudor-Locke, Catrine E; Kaufman, Jean-Marc; De Bourdeaudhuij, Ilse M

2011-08-01

Effectiveness of a behavioral modification program on physical activity (PA) and sedentary behavior in diabetes patients. Ninety-two patients were randomly assigned to an intervention or control group. The 24-weeks intervention consisted of a face-to-face session, pedometer and seven telephone follow-ups. Mean selection criteria were 35-75 years; 25-35 kg/m(2); ≤ 12% HbA1c, treated for type 2 diabetes; no PA limitations. PA and sedentary behavior were measured by pedometer, accelerometer and questionnaire over the short- (24 weeks) and intermediate- (1 year) term. The intervention group increased their steps/day by 2744, their total PA by 23 min/day (p<0.001) and decreased their sedentary behavior by 23 min/day (p<0.05) post-intervention. After 1 year the intervention group still had an increase of 1872 steps/day, 11 min/day total PA and a decrease of 12 min/day in sedentary behavior (p<0.001). This pedometer-based behavioral modification program with telephone support showed lasting positive effects on steps/day, PA and sedentary behavior. This study tested a convenient way to increase PA among type 2 diabetes patients. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

New stable ternary alkaline-earth metal Pb(II) oxides: Ca / Sr / BaPb 2 O 3 and BaPbO 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuwei; Zhang, Lijun; Singh, David J.

The different but related chemical behaviors of Pb(II) oxides compared to Sn(II) oxides, and the existence of known alkali/alkali-earth metal Sn(II) ternary phases, suggest that there should be additional ternary Pb(II) oxide phases. Here, we report structure searches on the ternary alkaline-earth metal Pb(II) oxides leading to four new phases. These are two ternary Pb(II) oxides, SrPb 2O 3 and BaPb 2O 3, which have larger chemical potential stability ranges compared with the corresponding Sn(II) oxides, and additionally two other ternary Pb(II) oxides, CaPb 2O 3 and BaPbO 2, for which there are no corresponding Sn(II) oxides. Those Pb(II) oxidesmore » are stabilized by Pb-rich conditions. These structures follow the Zintl behavior and consist of basic structural motifs of (PbO 3) 4- anionic units separated and stabilized by the alkaline-earth metal ions. They show wide band gaps ranging from 2.86 to 3.12 eV, and two compounds (CaPb 2O 3 and SrPb 2O 3) show rather light hole effective masses (around 2m 0). The valence band maxima of these compounds have a Pb-6s/O-2p antibonding character, which may lead to p-type defect (or doping) tolerant behavior. This then suggests alkaline-earth metal Pb(II) oxides may be potential p-type transparent conducting oxides.« less

New stable ternary alkaline-earth metal Pb(II) oxides: Ca / Sr / BaPb 2 O 3 and BaPbO 2

DOE PAGES

Li, Yuwei; Zhang, Lijun; Singh, David J.

2017-10-16

The different but related chemical behaviors of Pb(II) oxides compared to Sn(II) oxides, and the existence of known alkali/alkali-earth metal Sn(II) ternary phases, suggest that there should be additional ternary Pb(II) oxide phases. Here, we report structure searches on the ternary alkaline-earth metal Pb(II) oxides leading to four new phases. These are two ternary Pb(II) oxides, SrPb 2O 3 and BaPb 2O 3, which have larger chemical potential stability ranges compared with the corresponding Sn(II) oxides, and additionally two other ternary Pb(II) oxides, CaPb 2O 3 and BaPbO 2, for which there are no corresponding Sn(II) oxides. Those Pb(II) oxidesmore » are stabilized by Pb-rich conditions. These structures follow the Zintl behavior and consist of basic structural motifs of (PbO 3) 4- anionic units separated and stabilized by the alkaline-earth metal ions. They show wide band gaps ranging from 2.86 to 3.12 eV, and two compounds (CaPb 2O 3 and SrPb 2O 3) show rather light hole effective masses (around 2m 0). The valence band maxima of these compounds have a Pb-6s/O-2p antibonding character, which may lead to p-type defect (or doping) tolerant behavior. This then suggests alkaline-earth metal Pb(II) oxides may be potential p-type transparent conducting oxides.« less

Size dictated thermal conductivity of GaN

NASA Astrophysics Data System (ADS)

Beechem, Thomas E.; McDonald, Anthony E.; Fuller, Elliot J.; Talin, A. Alec; Rost, Christina M.; Maria, Jon-Paul; Gaskins, John T.; Hopkins, Patrick E.; Allerman, Andrew A.

2016-09-01

The thermal conductivity of n- and p-type doped gallium nitride (GaN) epilayers having thicknesses of 3-4 μm was investigated using time domain thermoreflectance. Despite possessing carrier concentrations ranging across 3 decades (1015-1018 cm-3), n-type layers exhibit a nearly constant thermal conductivity of 180 W/mK. The thermal conductivity of p-type epilayers, in contrast, reduces from 160 to 110 W/mK with increased doping. These trends—and their overall reduction relative to bulk—are explained leveraging established scattering models where it is shown that, while the decrease in p-type layers is partly due to the increased impurity levels evolving from its doping, size effects play a primary role in limiting the thermal conductivity of GaN layers tens of microns thick. Device layers, even of pristine quality, will therefore exhibit thermal conductivities less than the bulk value of 240 W/mK owing to their finite thickness.

Synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy of n-ZnO:Al/p-GaN:Mg heterojunction

NASA Astrophysics Data System (ADS)

Lee, Kai-Hsuan; Chang, Ping-Chuan; Chen, Tse-Pu; Chang, Sheng-Po; Shiu, Hung-Wei; Chang, Lo-Yueh; Chen, Chia-Hao; Chang, Shoou-Jinn

2013-02-01

Al-doped ZnO (AZO) deposited by radio frequency co-sputtering is formed on epitaxial Mg-doped GaN template at room temperature to achieve n-AZO/p-GaN heterojunction. Alignment of AZO and GaN bands is investigated using synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy on the nonpolar side-facet of a vertically c-axis aligned heterostructure. It shows type-II band configuration with valence band offset of 1.63 ± 0.1 eV and conduction band offset of 1.61 ± 0.1 eV, respectively. Rectification behavior is clearly observed, with a ratio of forward-to-reverse current up to six orders of magnitude when the bias is applied across the p-n junction.

Synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy of n-ZnO:Al/p-GaN:Mg heterojunction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Kai-Hsuan; Chen, Chia-Hao; Chang, Ping-Chuan

2013-02-18

Al-doped ZnO (AZO) deposited by radio frequency co-sputtering is formed on epitaxial Mg-doped GaN template at room temperature to achieve n-AZO/p-GaN heterojunction. Alignment of AZO and GaN bands is investigated using synchrotron radiation based cross-sectional scanning photoelectron microscopy and spectroscopy on the nonpolar side-facet of a vertically c-axis aligned heterostructure. It shows type-II band configuration with valence band offset of 1.63 {+-} 0.1 eV and conduction band offset of 1.61 {+-} 0.1 eV, respectively. Rectification behavior is clearly observed, with a ratio of forward-to-reverse current up to six orders of magnitude when the bias is applied across the p-n junction.

Analyzing the spatio-temporal relationship between dengue vector larval density and land-use using factor analysis and spatial ring mapping

PubMed Central

2012-01-01

Background Dengue, a mosquito-borne febrile viral disease, is found in tropical and sub-tropical regions and is now extending its range to temperate regions. The spread of the dengue viruses mainly depends on vector population (Aedes aegypti and Aedes albopictus), which is influenced by changing climatic conditions and various land-use/land-cover types. Spatial display of the relationship between dengue vector density and land-cover types is required to describe a near-future viral outbreak scenario. This study is aimed at exploring how land-cover types are linked to the behavior of dengue-transmitting mosquitoes. Methods Surveys were conducted in 92 villages of Phitsanulok Province Thailand. The sampling was conducted on three separate occasions in the months of March, May and July. Dengue indices, i.e. container index (C.I.), house index (H.I.) and Breteau index (B.I.) were used to map habitats conducible to dengue vector growth. Spatial epidemiological analysis using Bivariate Pearson’s correlation was conducted to evaluate the level of interdependence between larval density and land-use types. Factor analysis using principal component analysis (PCA) with varimax rotation was performed to ascertain the variance among land-use types. Furthermore, spatial ring method was used as to visualize spatially referenced, multivariate and temporal data in single information graphic. Results Results of dengue indices showed that the settlements around gasoline stations/workshops, in the vicinity of marsh/swamp and rice paddy appeared to be favorable habitat for dengue vector propagation at highly significant and positive correlation (p = 0.001) in the month of May. Settlements around the institutional areas were highly significant and positively correlated (p = 0.01) with H.I. in the month of March. Moreover, dengue indices in the month of March showed a significant and positive correlation (p <= 0.05) with deciduous forest. The H.I. of people living around horticulture land were significantly and positively correlated (p = 0.05) during the month of May, and perennial vegetation showed a highly significant and positive correlation (p = 0.001) in the month of March with C.I. and significant and positive correlation (p <= 0.05) with B.I., respectively. Conclusions The study concluded that gasoline stations/workshops, rice paddy, marsh/swamp and deciduous forests played highly significant role in dengue vector growth. Thus, the spatio-temporal relationships of dengue vector larval density and land-use types may help to predict favorable dengue habitat, and thereby enables public healthcare managers to take precautionary measures to prevent impending dengue outbreak. PMID:23043443

Analyzing the spatio-temporal relationship between dengue vector larval density and land-use using factor analysis and spatial ring mapping.

PubMed

Sarfraz, Muhammad Shahzad; Tripathi, Nitin K; Tipdecho, Taravudh; Thongbu, Thawisak; Kerdthong, Pornsuk; Souris, Marc

2012-10-09

Dengue, a mosquito-borne febrile viral disease, is found in tropical and sub-tropical regions and is now extending its range to temperate regions. The spread of the dengue viruses mainly depends on vector population (Aedes aegypti and Aedes albopictus), which is influenced by changing climatic conditions and various land-use/land-cover types. Spatial display of the relationship between dengue vector density and land-cover types is required to describe a near-future viral outbreak scenario. This study is aimed at exploring how land-cover types are linked to the behavior of dengue-transmitting mosquitoes. Surveys were conducted in 92 villages of Phitsanulok Province Thailand. The sampling was conducted on three separate occasions in the months of March, May and July. Dengue indices, i.e. container index (C.I.), house index (H.I.) and Breteau index (B.I.) were used to map habitats conducible to dengue vector growth. Spatial epidemiological analysis using Bivariate Pearson's correlation was conducted to evaluate the level of interdependence between larval density and land-use types. Factor analysis using principal component analysis (PCA) with varimax rotation was performed to ascertain the variance among land-use types. Furthermore, spatial ring method was used as to visualize spatially referenced, multivariate and temporal data in single information graphic. Results of dengue indices showed that the settlements around gasoline stations/workshops, in the vicinity of marsh/swamp and rice paddy appeared to be favorable habitat for dengue vector propagation at highly significant and positive correlation (p = 0.001) in the month of May. Settlements around the institutional areas were highly significant and positively correlated (p = 0.01) with H.I. in the month of March. Moreover, dengue indices in the month of March showed a significant and positive correlation (p <= 0.05) with deciduous forest. The H.I. of people living around horticulture land were significantly and positively correlated (p = 0.05) during the month of May, and perennial vegetation showed a highly significant and positive correlation (p = 0.001) in the month of March with C.I. and significant and positive correlation (p <= 0.05) with B.I., respectively. The study concluded that gasoline stations/workshops, rice paddy, marsh/swamp and deciduous forests played highly significant role in dengue vector growth. Thus, the spatio-temporal relationships of dengue vector larval density and land-use types may help to predict favorable dengue habitat, and thereby enables public healthcare managers to take precautionary measures to prevent impending dengue outbreak.

p-π Conjugated Polymers Based on Stable Triarylborane with n-Type Behavior in Optoelectronic Devices.

PubMed

Meng, Bin; Ren, Yi; Liu, Jun; Jäkle, Frieder; Wang, Lixiang

2018-02-19

p-π conjugation with embedded heteroatoms offers unique opportunities to tune the electronic structure of conjugated polymers. An approach is presented to form highly electron-deficient p-π conjugated polymers based on triarylboranes, demonstrate their n-type behavior, and explore device applications. By combining alternating [2,4,6-tris(trifluoromethyl)phenyl]di(thien-2-yl)borane (FBDT) and electron-deficient isoindigo (IID)/pyridine-flanked diketopyrrolopyrrole (DPPPy) units, we achieve low-lying lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels, high electron mobilities, and broad absorptions in the visible region. All-polymer solar cells with these polymers as electron acceptors exhibit encouraging photovoltaic performance with power conversion efficiencies of up to 2.83 %. These results unambiguously prove the n-type behavior and demonstrate the photovoltaic applications of p-π conjugated polymers based on triarylborane. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cross-plane electronic and thermal transport properties of p-type La0.67Sr0.33MnO3/LaMnO3 perovskite oxide metal/semiconductor superlattices

NASA Astrophysics Data System (ADS)

Jha, Pankaj; Sands, Timothy D.; Cassels, Laura; Jackson, Philip; Favaloro, Tela; Kirk, Benjamin; Zide, Joshua; Xu, Xianfan; Shakouri, Ali

2012-09-01

Lanthanum strontium manganate (La0.67Sr0.33MnO3, i.e., LSMO)/lanthanum manganate (LaMnO3, i.e., LMO) perovskite oxide metal/semiconductor superlattices were investigated as a potential p-type thermoelectric material. Growth was performed using pulsed laser deposition to achieve epitaxial LSMO (metal)/LMO (p-type semiconductor) superlattices on (100)-strontium titanate (STO) substrates. The magnitude of the in-plane Seebeck coefficient of LSMO thin films (<20 μV/K) is consistent with metallic behavior, while LMO thin films were p-type with a room temperature Seebeck coefficient of 140 μV/K. Thermal conductivity measurements via the photo-acoustic (PA) technique showed that LSMO/LMO superlattices exhibit a room temperature cross-plane thermal conductivity (0.89 W/m.K) that is significantly lower than the thermal conductivity of individual thin films of either LSMO (1.60 W/m.K) or LMO (1.29 W/m.K). The lower thermal conductivity of LSMO/LMO superlattices may help overcome one of the major limitations of oxides as thermoelectrics. In addition to a low cross-plane thermal conductivity, a high ZT requires a high power factor (S2σ). Cross-plane electrical transport measurements were carried out on cylindrical pillars etched in LSMO/LMO superlattices via inductively coupled plasma reactive ion etching. Cross-plane electrical resistivity data for LSMO/LMO superlattices showed a magnetic phase transition temperature (TP) or metal-semiconductor transition at ˜330 K, which is ˜80 K higher than the TP observed for in-plane resistivity of LSMO, LMO, or LSMO/LMO thin films. The room temperature cross-plane resistivity (ρc) was found to be greater than the in-plane resistivity by about three orders of magnitude. The magnitude and temperature dependence of the cross-plane conductivity of LSMO/LMO superlattices suggests the presence of a barrier with the effective barrier height of ˜300 meV. Although the magnitude of the cross-plane power factor is too low for thermoelectric applications by a factor of approximately 10-4—in part because the growth conditions chosen for this study yielded relatively high resistivity films—the temperature dependence of the resistivity and the potential for tuning the power factor by engineering strain, oxygen stoichiometry, and electronic band structure suggest that these epitaxial metal/semiconductor superlattices are deserving of further investigation.

Responsive parenting is associated with improved type 1 diabetes-related quality of life

PubMed Central

Botello-Harbaum, Maria; Nansel, Tonja; Haynie, Denise; Iannotti, Ronald J.; Simons-Morton, Bruce

2008-01-01

Background Improved quality of life is an important treatment goal for children and adolescents with type 1 diabetes. While previous research supports a relationship between family environment and quality of life, little research has addressed the relationship of parenting style constructs to quality of life in children with chronic disease. The present investigation assesses the relationship of parent responsiveness and demandingness with diabetes-related quality of life among children and adolescents with type 1 diabetes. Methods Baseline and 12-month follow-up self-report assessments were collected on a sample of 81 children with type 1 diabetes participating in an efficacy trial of a behavioral intervention to enhance adherence. The sample had a mean age of 13.3 years (SD = 1.7) and duration of diabetes of 7.7 years (SD = 3.7). Multiple regression analyses were conducted to determine the relationship of parent responsiveness and demandingness to diabetes-related quality of life at each time point. Results After adjusting for demographic and diabetes characteristics, as well as diabetes-specific parent-child behaviors, parent responsiveness was significantly associated with baseline diabetes-related quality of life (B=.23; p=.04). This relationship was sustained at 12-month follow-up (B=.22; p=.04) after adjusting for baseline quality of life and treatment group assignment, suggesting that parent responsiveness is associated with improved quality of life. Conclusions Findings indicate the importance of a supportive and emotionally warm parenting style in promoting improved quality of life for children with type 1 diabetes. Appropriate parenting skills should be an element of diabetes family management health care. PMID:18796059

Early Temperamental Antecedents of Adult Type A Behaviors.

ERIC Educational Resources Information Center

Steinberg, Laurence

1985-01-01

Data for this study of 108 young adults from the New York Longitudinal Study include measures of temperament derived from two sources: interviews conducted with subjects' mothers when the children were 3 and 4 years of age and measures of Type A behavior derived from interviews with the subjects during young adulthood. (Author/NH)

Characteristics and Hypothesized Functions of Challenging Behavior in a Community-Based Sample

ERIC Educational Resources Information Center

Petursdottir, Anna Ingeborg; Esch, John W.; Sautter, Rachael A.; Stewart, Kelise K.

2010-01-01

An archival study was conducted to document (a) types of challenging behavior, and (b) functional assessment outcomes, for a sample of persons with developmental disabilities who were referred to community-practicing behavior analysts for assessment and treatment of challenging behavior. Functional assessment reports, prepared by 17 behavior…

Dealing with Disruptive Behavior of Adult Learners

ERIC Educational Resources Information Center

Dobmeier, Robert; Moran, Joseph

2008-01-01

The adult education literature on disruptive behavior of adult learners was reviewed and a survey on disruptive behavior of adult learners was conducted with adult educators. The findings are synthesized in a conceptual framework for understanding the types and causes of disruptive behavior, which fall into the categories of inattention,…

[Study on the prevalence of HIV infection and related risk behaviors among male new-type drug users in Qingdao, Shandong province].

PubMed

Li, D M; Lu, S; Li, P L; Ge, L; Tao, X R; Jiang, Z X; Liao, M Z; Cui, Y

2018-06-10

Objective: To understand the characteristics of new-type drug consumption, sexual behaviors and the prevalence of HIV infection among male new-type drug users in Qingdao, Shandong province. Methods: A cross sectional survey was conducted from 2015 to 2016. Participants were recruited from MSM community-based organizations (CBO) and general community through snowball method, relying on volunteers and male peer educators who were on new-type drugs themselves. Face-to-face interview was carried to collect information on drug use and sexual behaviors. Blood samples were collected to test HIV, syphilis and HCV antibodies. Urine samples were collected to test the evidence of new-type drugs. Qualitative variables and quantitative variables were analyzed using Chi-square test/Fisher's exact test and Student's t -test respectively. Multivariate logistic regression was used to analyze related factors of binary variables. Results: A total of 1 034 newtype drug users were recruited, including 431 (41.7 % ) MSM population and 603 (58.3 % ) who were not MSM. Compared with the the group of people who were not MSM, people in the the MSM group were younger, unmarried and with higher level of education. The proportion of methamphetamine users were 49.7 % (214/431) and 100.0 % (603/603) among the groups of MSM or not MSM, respectively. People in the MSM group, 66.8 % (288/431) used 5-Methoxy-N, N-diisopropyltryptamine (5-MeODIPT, "foxy" ) in the last six months. However, none from the not-MSM group ever used 5-MeO-DIPT. In the last six months, proportions of sharing new-type drugs with more than two people in the MSM or not groups were 87.9 % (379/431) and 97.7 % (588/602), respectively ( χ (2)=39.84, P <0.01). Proportions of unprotected sexual behavior among the MSM or not groups were 47.5 % (285/600) and 7.4 % (32/430) respectively ( χ (2)=190.10, P <0.01). The proportions of 'group sex' after using drugs among the two groups were 78.1 % (335/429) and 5.5 % (33/600) respectively ( χ (2)=573.73, P <0.01). The prevalence rates of HIV, syphilis and HCV antibody positive among the MSM or not groups were 2.1 % and 0.2 % , 3.3 % and 6.3 % , 0.0 % and 0.3 % , respectively. Conclusion: The prevalence of sharing new-type drugs with more than two people was high among male new-type drug users in Qingdao city. Male new-type-drug-users who were MSM, presented both high prevalence of group sex and HIV infection, and with less condom use. Intervention measures towards this sub-population should be strengthened.

Behavioral Analysis of Chinese Adult Patients with Type 1 Diabetes on Self-monitoring of Blood Glucose.

PubMed

Qin, Zhao-Yi; Yan, Jin-Hua; Yang, Dai-Zhi; Deng, Hong-Rong; Yao, Bin; Weng, Jian-Ping

The information-motivation-behavioral skills (IMB) model of health behavior is an effective tool to evaluate the behavior of diabetes self-management. The purpose of this study was to explore behavioral factors affecting the practice of self-monitoring of blood glucose (SMBG) within the frame of IMB model of health behavioral among adult patients with type 1 diabetes in a single diabetes clinic in China. A questionnaire with three subscales on SMBG information, motivation, and behavioral skills based on IMB model was developed. Validity and reliability of the measures were examined and guaranteed. Adult patients with type 1 diabetes visiting our diabetes clinic from January to March 2012 (n = 55) were consecutively interviewed. The self-completion questionnaires were administered and finished at face-to-face interviews among these patients. Both descriptive and correlational analyses were made. Fifty-five patients finished the questionnaires, with the median duration of diabetes 4.5 years and the median of SMBG frequency 2.00. Specific SMBG information deficits, motivation obstacles, and behavioral skill limitations were identified in a substantial proportion of participants. Scores of SMBG motivation (r = 0.299, P= 0.026) and behavioral skills (r = 0.425, P= 0.001) were significantly correlated with SMBG frequency. The multiple correlation of SMBG information, SMBG motivation, and SMBG behavioral skills with SMBG frequency was R = 0.411 (R2 = 0.169, P= 0.023). Adult patients with type 1 diabetes in our clinic had substantial SMBG information deficits, motivation obstacles, and skill limitations. This information provided potential-focused education targets for diabetes health-care providers.

Northern bobwhite predator avoidance behavior in response to varying types of threat

USGS Publications Warehouse

Perkins, R.A.; Boal, Clint W.; Rollins, Dale; Perez, R.

2014-01-01

The flight behavior and cover use of northern bobwhite (Colinus virginianus) have been examined in several studies, but the current data lack quantitative measures of how bobwhites respond to natural threats. We examined aspects of bobwhite behavior in response to 4 threat categories: researcher, hunter, raptor, and mammal. We found that bobwhite flight distance is best predicted by threat type and covey size, and bobwhite flight speed is best predicted by threat type. Bobwhites flushed by the hunter threat and the raptor threat selected for significantly taller obstruction at landing sites than was randomly available, with average heights of 6.2cm taller (P=0.034), and 38.1cm taller (P<0.001), respectively. Raptor-flushed bobwhites also selected for significantly denser shrub cover (42.2%, P<0.001) and a lower angle of obstruction (70.4 degrees, P<0.001) at landing points than was randomly available. In the process of data collection, we also observed bobwhite roost locations have lower visual height obstruction (7.3cm, P=0.03), lower shrub intercept (10.1%, P=0.02), and greater angles of obstruction (18.5 degrees, P=0.005) than bobwhite diurnal locations; this may facilitate escape from nocturnal mammalian predators. Our results suggest that bobwhite escape strategies and cover use vary among threat types. These results support current management recommendations of creating a patchwork of vegetation covers for bobwhites but also suggest how a more complete understanding of bobwhite behavior would improve management and conservation efforts.

Leakage conduction behavior in electron-beam-cured nanoporous silicate films

NASA Astrophysics Data System (ADS)

Liu, Po-Tsun; Tsai, T. M.; Chang, T. C.

2005-05-01

This letter explores the application of electron-beam curing on nanoporous silicate films. The electrical conduction mechanism for the nanoporous silicate film cured by electron-beam radiation has been studied with metal-insulator-semiconductor capacitors. Electrical analyses over a varying temperature range from room temperature to 150°C provide evidence for space-charge-limited conduction in the electron-beam-cured thin film, while Schottky-emission-type leaky behavior is seen in the counterpart typically cured by a thermal furnace. A physical model consistent with electrical analyses is also proposed to deduce the origin of conduction behavior in the nanoporous silicate thin film.

Thermal process induced change of conductivity in As-doped ZnO

NASA Astrophysics Data System (ADS)

Su, S. C.; Fan, J. C.; Ling, C. C.

2012-02-01

Arsenic-doped ZnO films were fabricated by radio frequency magnetron sputtering method with different substrate temperature TS. Growing with the low substrate temperature of TS=200°C yielded n-type semi-insulating sample. Increasing the substrate temperature would yield p-type ZnO film and reproducible p-type film could be produced at TS~450°C. Post-growth annealing of the n-type As-doped ZnO sample grown at the low substrate temperature (TS=200°C) in air at 500°C also converted the film to p-type conductivity. Further increasing the post-growth annealing temperature would convert the p-type sample back to n-type. With the results obtained from the studies of positron annihilation spectroscopy (PAS), photoluminescence (PL), cathodoluminescence (CL), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectroscopy (SIMS) and nuclear reaction analysis (NRA), we have proposed mechanisms to explain for the thermal process induced conduction type conversion as observed in the As-doped ZnO films.

Relations of behavioral autonomy to health outcomes among emerging adults with and without type 1 diabetes.

PubMed

Helgeson, Vicki S; Reynolds, Kerry A; Becker, Dorothy; Escobar, Oscar; Siminerio, Linda

2014-01-01

To examine the relation of behavioral autonomy to psychological, behavioral, and physical health among emerging adults with and without type 1 diabetes. High school seniors with (n = 118) and without type 1 diabetes (n = 122) completed online questionnaires for three consecutive years. Behavioral autonomy, psychological health, risk behaviors, and diabetes outcomes were assessed. Regression analyses were conducted to predict Time 2 and 3 outcomes, controlling for Time 1 outcomes. There were no group differences in behavioral autonomy. Behavioral autonomy predicted better psychological health but only for emerging adults without diabetes. Behavioral autonomy was related to increased risk behavior for both groups. Behavioral autonomy was unrelated to self-care but predicted better glycemic control for females. Behavioral autonomy may be beneficial for psychological health, but is related to increased risk behavior. The implications of behavioral autonomy for emerging adults with type 1 diabetes require careful consideration. © The Author 2014. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Spin-glass behaviors in carrier polarity controlled Fe{sub 3−x}Ti{sub x}O{sub 4} semiconductor thin films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamahara, H., E-mail: yamahara@bioxide.t.u-tokyo.ac.jp; Seki, M.; Adachi, M.

2015-08-14

Carrier-type control of spin-glass (cluster spin-glass) is studied in order to engineer basic magnetic semiconductor elements using the memory functions of spin-glass. A key of carrier-polarity control in magnetite is the valence engineering between Fe(II) and Fe(III) that is achieved by Ti(IV) substitution. Single phases of (001)-oriented Fe{sub 3−x}Ti{sub x}O{sub 4} thin films have been obtained on spinel MgAl{sub 2}O{sub 4} substrates by pulsed laser deposition. Thermoelectric power measurements reveal that Ti-rich films (x = 0.8) show p-type conduction, while Ti-poor films (x = 0.6–0.75) show n-type conduction. The systematic Fe(III) reduction to Fe(II) followed by Ti(IV) substitution in the octahedral sublattice is confirmedmore » by the X-ray absorption spectra. All of the Fe{sub 3−x}Ti{sub x}O{sub 4} films (x = 0.6–0.8) exhibit ferrimagnetism above room temperature. Next, the spin-glass behaviors of Ti-rich Fe{sub 2.2}Ti{sub 0.8}O{sub 4} film are studied, since this magnetically diluted system is expected to exhibit the spin-glass behaviors. The DC magnetization and AC susceptibility measurements for the Ti-rich Fe{sub 2.2}Ti{sub 0.8}O{sub 4} film reveal the presence of the spin glass phase. Thermal- and magnetic-field-history memory effects are observed and are attributed to the long time-decay nature of remanent magnetization. The detailed analysis of the time-dependent thermoremanent magnetization reveals the presence of the cluster spin glass state.« less

Analysis of Associations between Behavioral Traits and Four Types of Aggression in Shiba Inu

PubMed Central

KANEKO, Fumihiro; ARATA, Sayaka; TAKEUCHI, Yukari; MORI, Yuji

2013-01-01

ABSTRACT Canine aggression is one of the behavioral problems for which veterinary behaviorists are most frequently consulted. Despite this, the classification of canine aggression is controversial, and there are several classification methodologies. While the etiology of canine aggression differs among the types of aggression, the behavioral background underlying aggression is not well understood. Behavior trait-based evaluation of canine aggression would improve the effectiveness and efficiency of managing canine aggression problems. We developed a questionnaire addressing 14 behavioral items and items related to four types of canine aggression (owner-, child-, stranger- and dog-directed aggression) in order to examine the associations between behavioral traits and aggression in Shiba Inu. A total of 400 Shiba Inu owners recruited through dog events (n=134) and veterinary hospitals (n=266) completed the questionnaire. Factor analysis sorted the behavioral items from both the event and clinic samples into four factors: “sociability with humans,” “reactivity to stimuli,” “chase proneness” and “fear of sounds.” While “reactivity to stimuli” correlated significantly positively with all of the four types of aggression (P=0.007 to <0.001), “sociability with humans” correlated significantly negatively with child- and stranger-directed aggression (P<0.001). These results suggest that the behavioral traits involved in canine aggression differ among the types of aggression and that specific behavioral traits are frequently simultaneously involved in several types of aggression. PMID:23719752

A promising p-type transparent conducting material: Layered oxysulfide [Cu2S2][Sr3Sc2O5

NASA Astrophysics Data System (ADS)

Liu, Min-Ling; Wu, Li-Bin; Huang, Fu-Qiang; Chen, Li-Dong; Chen, I.-Wei

2007-12-01

Sr3Cu2Sc2O5S2, a layered oxysulfide, composed of anti-PbO-like [Cu2S2] slabs alternating with perovskitelike [Sr3Sc2O5] slabs, was systematically studied as a p-type transparent conducting material. The material has a wide energy gap of 3.1eV and a p-type electrical conductivity of 2.8Scm-1 at room temperature. The hole mobility of +150cm2V-1S-1 at room temperature, which is much higher than the typical value of ˜10-1-10width="0.3em"/>cm2V-1S-1 found in other copper compounds. The performances of bulk undoped Sr3Cu2Sc2O5S2 show the promise of copper oxysulfides as a class of p-type transparent conductive materials that is essential for optoelectronic applications.

Quantifying the Performance of P-Type Transparent Conducting Oxides by Experimental Methods

PubMed Central

Fleischer, Karsten; Norton, Emma; Mullarkey, Daragh; Caffrey, David; Shvets, Igor V.

2017-01-01

Screening for potential new materials with experimental and theoretical methods has led to the discovery of many promising candidate materials for p-type transparent conducting oxides. It is difficult to reliably assess a good p-type transparent conducting oxide (TCO) from limited information available at an early experimental stage. In this paper we discuss the influence of sample thickness on simple transmission measurements and how the sample thickness can skew the commonly used figure of merit of TCOs and their estimated band gap. We discuss this using copper-deficient CuCrO2 as an example, as it was already shown to be a good p-type TCO grown at low temperatures. We outline a modified figure of merit reducing thickness-dependent errors, as well as how modern ab initio screening methods can be used to augment experimental methods to assess new materials for potential applications as p-type TCOs, p-channel transparent thin film transistors, and selective contacts in solar cells. PMID:28862695

Profiles in the Development of Behavior Disorders among Youths with Family Maltreatment Histories

ERIC Educational Resources Information Center

Desbiens, Nadia; Gagne, Marie-Helene

2007-01-01

Violent conduct by youths ranks among the types of inappropriate behavior generally originating in difficult family and social contexts. A proper understanding of the development of violent conduct must consider the situation taken as a whole. This article documents the results of a qualitative study which aimed to determine the psychosocial…

Seebeck Effects in N-Type and P-Type Polymers Driven Simultaneously by Surface Polarization and Entropy Differences Based on Conductor/Polymer/Conductor Thin-Film Devices

DOE PAGES

Hu, Dehua; Liu, Qing; Tisdale, Jeremy; ...

2015-04-15

This paper reports Seebeck effects driven by both surface polarization difference and entropy difference by using intramolecular charge-transfer states in n-type and p-type conjugated polymers, namely IIDT and IIDDT, based on vertical conductor/polymer/conductor thin-film devices. Large Seebeck coefficients of -898 V/K and 1300 V/K from are observed from n-type IIDT p-type IIDDT, respectively, when the charge-transfer states are generated by a white light illumination of 100 mW/cm2. Simultaneously, electrical conductivities are increased from almost insulating states in dark condition to conducting states under photoexcitation in both n-type IIDT and p-type IIDDT devices. We find that the intramolecular charge-transfer states canmore » largely enhance Seebeck effects in the n-type IIDT and p-type IIDDT devices driven by both surface polarization difference and entropy difference. Furthermore, the Seebeck effects can be shifted between polarization and entropy regimes when electrical conductivities are changed. This reveals a new concept to develop Seebeck effects by controlling polarization and entropy regimes based on charge-transfer states in vertical conductor/polymer/conductor thin-film devices.« less

Nanoscale electrical characteristics of metal (Au, Pd)-graphene-metal (Cu) contacts

NASA Astrophysics Data System (ADS)

Ruffino, F.; Meli, G.; Grimaldi, M. G.

2016-01-01

Free-standing graphene presents exceptional physical properties (as a high carrier mobility) making it the ideal candidate for the next generation nanoelectronics. However, when graphene layers are inserted in real electronics devices, metal contacting is required. The metal-graphene interaction significantly affects the graphene electrical properties, drastically changing its behavior with respect to the free-standing configuration. So, this work presents an experimental study on the nanoscale electric characteristics of metal/graphene/metal contacts. In particular, starting from single-layer graphene grown on Cu foil we deposited on the graphene surface two different metal films (Au or Pd) and the Au/graphene/Cu and Pd/graphene/Cu current-voltage characteristics are acquired, on the nanometric scale, by the conductive atomic force microscopy. Both systems presented a current voltage rectifying behavior. However, the Au/graphene/Cu system conducts significantly at negative applied bias (graphene behaves as a p-type semiconductor in a meta/semiconductor contact), while in the Pd/graphene/Cu at positive applied bias (graphene behaves as a n-type semiconductor in a metal/semiconductor contact). This difference is discussed on the basis of the band energy diagram at the metal/graphene interface and the modification of the graphene Fermi level due to the Au/graphene or Pd/graphene interaction.

Doping in controlling the type of conductivity in bulk and nanostructured thermoelectric materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuks, D.; Komisarchik, G.; Kaller, M.

2016-08-15

Doping of materials for thermoelectric applications is widely used nowadays to control the type of conductivity. We report the results of ab-initio calculations aimed at developing the consistent scheme for determining the role of impurities that may change the type of conductivity in two attractive thermoelectric classes of materials. It is demonstrated that alloying of TiNiSn with Cu makes the material of n-type, and alloying with Fe leads to p-type conductivity. Similar calculations for PbTe with small amount of Na substituting for Pb leads to p-type conductivity, while Cl substituting for Te makes PbTe an n-type material. It is shownmore » also that for nano-grained materials the n-type conductivity should be observed. The effect of impurities segregating to the grain boundaries in nano-structured PbTe is also discussed. - Highlights: • Bulk and nano-grained TE materials were analyzed by DFT. • The electronic effects on both PbTe and TiNiSn were demonstrated. • The role of impurities on the conductivity type was analyzed. • Interfacial states in nano-grained PbTe affect the conductivity type.« less

Parenting behaviors associated with risk for offspring personality disorder during adulthood.

PubMed

Johnson, Jeffrey G; Cohen, Patricia; Chen, Henian; Kasen, Stephanie; Brook, Judith S

2006-05-01

Research has suggested that some types of parental child-rearing behavior may be associated with risk for offspring personality disorder (PD), but the association of parenting with offspring PD has not been investigated comprehensively with prospective longitudinal data. To investigate the association of parental child-rearing behavior with risk for offspring PD during adulthood. The Children in the Community study, a prospective longitudinal investigation. A community-based sample of 593 families interviewed during childhood (mean age, 6 years), adolescence (mean ages, 14 and 16 years), emerging adulthood (mean age, 22 years), and adulthood (mean age, 33 years) of the offspring. The Structured Clinical Interview for DSM-IV Personality Disorders. Ten types of parenting behavior that were evident during the child-rearing years were associated with elevated offspring risk for PD during adulthood when childhood behavioral or emotional problems and parental psychiatric disorders were controlled statistically. Parental behavior in the home during the child-rearing years was associated with elevated risk for offspring PD at mean ages of 22 and 33 years. Risk for offspring PD at both assessments increased steadily as a function of the number of problematic parenting behaviors that were evident. Low parental affection or nurturing was associated with elevated risk for offspring antisocial (P = .003), avoidant (P = .01), borderline (P = .002), depressive (P = .02), paranoid (P = .002), schizoid (P = .046), and schizotypal (P<.001) PDs. Aversive parental behavior (eg, harsh punishment) was associated with elevated risk for offspring borderline (P = .001), paranoid (P = .004), passive-aggressive (P = .046), and schizotypal (P = .02) PDs. Parental behavior during the child-rearing years may be associated with risk for offspring PD that endures into adulthood. This risk may not be attributable to offspring behavioral and emotional problems or parental psychiatric disorder, and it may not diminish over time. Low parental nurturing and aversive parental behavior during child rearing may both be associated with elevated risk for offspring PDs.

Giant magnetoresistance and anomalous transport in phosphorene-based multilayers with noncollinear magnetization

NASA Astrophysics Data System (ADS)

Zare, Moslem; Majidi, Leyla; Asgari, Reza

2017-03-01

We theoretically investigate the unusual features of the magnetotransport in a monolayer phosphorene ferromagnetic/normal/ferromagnetic (F/N/F) hybrid structure. We find that the charge conductance can feature a minimum at parallel (P) configuration and a maximum near the antiparallel (AP) configuration of magnetization in the F/N/F structure with n -doped F and p -doped N regions and also a finite conductance in the AP configuration with the N region of n -type doping. In particular, the proposed structure exhibits giant magnetoresistance, which can be tuned to unity. This perfect switching is found to show strong robustness with respect to increasing the contact length and tuning the chemical potential of the N region with a gate voltage. We also explore the oscillatory behavior of the charge conductance or magnetoresistance in terms of the size of the N region. We further demonstrate the penetration of the spin-transfer torque into the right F region and show that, unlike graphene structure, the spin-transfer torque is very sensitive to the chemical potential of the N region as well as the exchange field of the F region.

Experimental and Theoretical Evidences of p-Type Conductivity in Nickel Carbodiimide Nanoparticles with a Delafossite Structure Type.

PubMed

Jiang, Tengfei; Polteau, Baptiste; Farré, Yoann; Cario, Laurent; Latouche, Camille; Pellegrin, Yann; Boujtita, Mohammed; Odobel, Fabrice; Tessier, Franck; Cheviré, François; Jobic, Stéphane

2017-07-17

Nickel carbodiimide (NiCN 2 ) was synthesized using a two-step precipitation-decomposition route leading to a brown powder with gypsum-flower-like morphology and a large specific surface area (75 m 2 /g). This layered material crystallizes in the 2H structure type of delafossite (space group P6 3 /mmc), which is built upon infinite 2 / ∞ [NiN 2 ] layers connected by linear carbodiimide ([N═C═N] 2- ) bridges. An X-ray diffraction Rietveld refinement and thermal analyses pointed out some nickel deficiencies in the material, and band structure calculations carried out on the defect compound predicted p-type conductivity in relation to a slight amount of N 2- . This p-type conductivity was demonstrated by electrochemical impedance spectroscopy measurements, and a flat band potential of 0.90 V vs SCE at pH 9.4 was measured. This value, which is more positive than those of CuGaO 2 and CuCrO 2 delafossite oxides and NiO, prompted us to test NiCN 2 nanoparticles as a photocathode in p-type dye-sensitized solar cells.

Intimate Partner Violence and HIV Risk Behaviors Among Socially Disadvantaged Chilean Women

PubMed Central

Miner, Sarah; Ferrer, Lilian; Cianelli, Rosina; Bernales, Margarita; Cabieses, Báltica

2012-01-01

The objective of this study was to determine if a relationship exists between intimate partner violence (IPV) and HIV risk among socioeconomically disadvantaged Chilean women. A correlational analysis with data from the NIH-funded project, “Testing an HIV/AIDS Prevention Intervention for Chilean Women,” was conducted. Two hundred and sixtyone women were included in this analysis (n = 261). Those women who had experienced any type of IPV in the past 3 months had significantly higher risk for HIV than those who had not (t = −2.016, p < .05). Also a linear trend was found among those women who had experienced more than one type of IPV in the past 3 months and HIV risk. PMID:21486859

Molecular basis of proton block of L-type Ca2+ channels.

PubMed

Chen, X H; Bezprozvanny, I; Tsien, R W

1996-11-01

Hydrogen ions are important regulators of ion flux through voltage-gated Ca2+ channels but their site of action has been controversial. To identify molecular determinants of proton block of L-type Ca2+ channels, we combined site-directed mutagenesis and unitary current recordings from wild-type (WT) and mutant L-type Ca2+ channels expressed in Xenopus oocytes. WT channels in 150 mM K+ displayed two conductance states, deprotonated (140 pS) and protonated (45 pS), as found previously in native L-type Ca2+ channels. Proton block was altered in a unique fashion by mutation of each of the four P-region glutamates (EI-EIV) that form the locus of high affinity Ca2+ interaction. Glu(E)-->Gln(Q) substitution in either repeats I or III abolished the high-conductance state, as if the titration site had become permanently protonated. While the EIQ mutant displayed only an approximately 40 pS conductance, the EIIIQ mutant showed the approximately 40 pS conductance plus additional pH-sensitive transitions to an even lower conductance level. The EIVQ mutant exhibited the same deprotonated and protonated conductance states as WT, but with an accelerated rate of deprotonation. The EIIQ mutant was unusual in exhibiting three conductance states (approximately 145, 102, 50 pS, respectively). Occupancy of the low conductance state increased with external acidification, albeit much higher proton concentration was required than for WT. In contrast, the equilibrium between medium and high conductance levels was apparently pH-insensitive. We concluded that the protonation site in L-type Ca2+ channels lies within the pore and is formed by a combination of conserved P-region glutamates in repeats I, II, and III, acting in concert. EIV lies to the cytoplasmic side of the site but exerts an additional stabilizing influence on protonation, most likely via electrostatic interaction. These findings are likely to hold for all voltage-gated Ca2+ channels and provide a simple molecular explanation for the modulatory effect of H+ ions on open channel flux and the competition between H+ ions and permeant divalent cations. The characteristics of H+ interactions advanced our picture of the functional interplay between P-region glutamates, with important implications for the mechanism of Ca2+ selectivity and permeation.

Synthesis and Thermoelectric Properties of Partially Double-Filled (Ce1- z Pr z ) y Fe4- x Co x Sb12 Skutterudites

NASA Astrophysics Data System (ADS)

Cha, Ye-Eun; Shin, Dong-Kil; Kim, Il-Ho

2018-06-01

Partially double-filled p-type (Ce1- z Pr z ) y Fe4- x Co x Sb12 ( z = 0.25, 0.75; y = 0.8; x = 0, 0.5, 1.0) skutterudites were synthesized by encapsulated melting and consolidated by hot pressing. The microstructure, phase, charge transport characteristics, and thermoelectric properties of the hot-pressed specimens were analyzed. Detailed measurements indicated that the skutterudite phase was successfully synthesized, but a small amount of a secondary phase (FeSb2) was also identified. However, the amount of the FeSb2 phase decreased with an increase in the Co substitution. Unlike for the filled Ce1- z Pr z Fe4- x Co x Sb12 skutterudites with y = 1, the (Ce,Pr)Sb2 phases were not formed by partial filling with Ce/Pr. The electrical conductivity decreased with increasing temperature, similar to the behavior shown by degenerate semiconductors. The Hall coefficient and the Seebeck coefficients were positive, indicating that all specimens exhibited p-type characteristics. The electrical conductivity and the electronic thermal conductivity decreased with increasing Pr filling and Co substitution because of the decreased carrier concentration caused by charge compensation. A maximum dimensionless figure of merit, ZTmax = 0.84, was obtained at 623 K for (Ce0.75Pr0.25)0.8Fe3CoSb12.

Health behaviors of head and neck cancer patients the first year after diagnosis.

PubMed

Duffy, Sonia A; Khan, Mumtaz J; Ronis, David L; Fowler, Karen E; Gruber, Stephen B; Wolf, Gregory T; Terrell, Jeffrey E

2008-01-01

This prospective, cohort study is the first to describe 5 health behaviors of head and neck cancer patients the first year after diagnosis. Patients (N = 283) were recruited in otolaryngology clinic waiting rooms and asked to complete written surveys. A medical record audit was also conducted. Descriptive statistics and multivariate analyses were conducted to determine which variables were associated with the 5 health behaviors. Half of the patients smoked and 25% were problem drinkers. Over half of the smokers and drinkers quit 1 year post-diagnosis. Smoking and problem drinking were highly associated and both were associated with lower body mass index (BMI) (p < .01). Moreover, physical activity and sleep were associated with each other (p < .01). Low SLEEP (Medical Outcomes Study Sleep Scale) scores were common and highly associated with depression (p < .01). The health behaviors of head and neck cancer patients are interrelated, and assessing and treating these behaviors together may be beneficial. Copyright (c) 2007 Wiley Periodicals, Inc.

Sex-Typed Teaching Styles of University Professors and Student Reactions. Final Report, October 1, 1978 - December 31, 1979.

ERIC Educational Resources Information Center

Macke, Anne Statham; And Others

Teaching styles and possible sex-typed differences in teaching approaches were studied at Ohio State University. Classroom teaching behaviors of 167 professors were observed, and interviews with a subsample of 30 professors were conducted. Additionally, student reactions to these classroom behaviors were assessed through a questionnaire…

Comparing the effects of education using telephone follow-up and smartphone-based social networking follow-up on self-management behaviors among patients with hypertension.

PubMed

Najafi Ghezeljeh, Tahereh; Sharifian, Sanaz; Nasr Isfahani, Mehdi; Haghani, Hamid

2018-03-05

Little is known about the benefits of social networks in the management of patients. The aim of this study was to compare the effects of self-management (SM) education using telephone follow-up and mobile phone-based social networking on SM behaviors among patients with hypertension. This randomized clinical trial was conducted with 100 patients. They were randomly allocated to four groups: (i) control, (ii) SM training without follow-up, (iii) telephone follow-up and (iv) smartphone-based social networking follow-up. The hypertension SM behavior questionnaire was used for data collection before and six weeks after the study. Those patients who underwent SM education training (with and without follow-up) had statistically significant differences from those in the control group in terms of SM behaviors (p < .001). There was no statistically significant difference between different types of follow-up. SM education using telephone follow-up and/or smartphone-based social networking follow-up influenced SM behaviors among patients with hypertension.

Characterization of Carbonates by Spectral Induced Polarization

NASA Astrophysics Data System (ADS)

Hupfer, Sarah; Halisch, Matthias; Weller, Andreas

2017-04-01

This study investigates the complex electrical conductivity of carbonate samples by Spectral Induced Polarization (SIP). The analysis is conducted in combination with petrophysical, mineralogical and geochemical measurements. SIP is a useful tool to obtain more detailed information about rock properties and receive a more qualitative pore space characterization. Rock parameters like permeability, pore-size and -surface area can be predicted. Up to this point, sandstones or sandy materials were investigated in detail by laboratory SIP-measurements. Several robust empirical relationships were found that connect IP-signals and petrophysical parameters (surface area, surface conductivity and cation exchange capacity). Different types of carbonates were analyzed with laboratory SIP-measurements. Rock properties like grain density, porosity, permeability and surface area were determined by petrophysical measurements. Geochemistry and mineralogy were used to differentiate the carbonate types. First results of the SIP-measurements showed polarization effects for all different types. Four different phase behavior were observed in the phase spectra. A constant phase angle, a constant slope, a combination of both and a maximum type could be identified. Each phase behavior can be assigned to the specific carbonate type used, but the constant phase occurs at two carbonate types. Further experiments were conducted to get more insight the phase behavior and get explanations. 1. Approach: An expected phase peak frequency for each sample was calculated to check if this frequency is within the measured spectrum of 2 mHz to 100 Hz. 2. Approach: Significantly reducing of the fluid conductivity to increase phase signal for a better interpretation. 3. Approach: The cation-exchange-capacity (CEC) was regarded as a factor as well. A dependence between imaginary part of conductivity and CEC was detected. 4. Approach: Imaging procedures (scanning electron microscope, x-ray computed tomography, microscopy) were used to create a qualitative image of the carbonate samples and to investigate the pore space, for example the ratio of connected to non-connected pore space. A comparison between SIP data and the petrophysical data of the sample set showed that the phase behavior of carbonates is highly complicated and challenging compared with sandstones. It seems that there is no correlation between polarization effects and any petrophysical parameter. Ongoing investigations and measurements will be conducted to get more insight to the polarization effects of carbonates.

Gender Differences and Correlated Factors of Heroin Use Among Heroin Users.

PubMed

Zhou, Xiaobo; Yi, Zhihua; Yang, Xiaorong; Wang, Zhuo; Lyu, Xianxiang; Li, Jing

2017-01-02

Gender differences in illicit drug use are becoming increasingly recognized. However, there are few studies concerning differences between male and female heroin users in China. The study aimed to explore gender differences in terms of socio-demographic characteristics, drug-related behaviors, and treatment history among a heroin-using population in China. A cross-sectional study was conducted in four cities in December 2013. A total of 788 participants were recruited from several types of sites in each city: compulsory detoxification centers, methadone maintenance treatment clinics, and detention facilities. The data were collected via a self-administered questionnaire. Analysis of variance, chi-square test, and multivariate logistic regression analyses were conducted to examine gender differences in socio-demographic characteristics, drug-related behaviors, and treatment history. Female heroin users were more likely to be unemployed, have more education, and use heroin with their spouse/companion (p <.05). Male heroin users were more likely to be in detention facilities and MMT clinics, and relapse when they felt hopeless (p <.05). Conclusions/Importance: Although there were some similarities between male and female heroin users, significant gender differences do exist in some aspects of socio-demographic characteristics and heroin use. The data provide evidence that interventions aimed at preventing the initiation of heroin use and reducing relapse should take gender into account.

The impact of training on women's capabilities in modifying their obesity-related dietary behaviors: applying family-centered empowerment model.

PubMed

Mataji Amirrood, Maryam; Taghdisi, Mohammad Hosein; Shidfar, Farzad; Gohari, Mahmood Reza

2014-01-01

Dietary behaviors affect obesity; therefore, it seems necessary to conduct interventions to modify behavioral patterns leading to weight-gain in the family. Our goal was to determine the impact of training on women's capabilities in modifying their obesity-related dietary behaviors in Urmia, West Azerbaijan Province, Iran: applying family-centered empowerment model. A quasi-experimental study with Pretest-Posttest design was conducted on 90 over-weight/obese women in 2012 in two Health Centers of Urmia. Convenience sampling was done and the participants were randomly assigned to two 'test' and 'control' groups. Data collection was done by completing the demographic data questionnaire, the empowerment tool and dietary behavior checklist. The intervention was conducted in the form of 6 educational classes held for the 'test' group. After two months, posttest was performed by completing the forms once again. Data were analyzed with descriptive tests, t-tests, Chi2 and Fischer's test. The dietary behavior scores of the intervention group had risen from 7.4 ± 2.11 to 9.95 ± 2.41 (P<0.001), and the good dietary behaviors had risen from 21.4% to 61.9% (P=0.002). The 'good' capability level of this group had risen from 23.8% to 97.61% (P<0.001), and their mean capability score had risen from 54.61 ± 7.34 to 70.26 ± 6.04 (P<0.001). However, the changes were not significant in the control group. The educational intervention performed whit applying family-centered empowerment model in this study was proven effective in women. Hence it is advised to consider it in behavior changing interventions to promote the health of the family and community.

Patterned growth of p-type MoS 2 atomic layers using sol-gel as precursor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Wei; Lin, Junhao; Feng, Wei

2D layered MoS 2 has drawn intense attention for its applications in flexible electronic, optoelectronic, and spintronic devices. Most of the MoS 2 atomic layers grown by conventional chemical vapor deposition techniques are n-type due to the abundant sulfur vacancies. Facile production of MoS 2 atomic layers with p-type behavior, however, remains challenging. Here, a novel one-step growth has been developed to attain p-type MoS 2 layers in large scale by using Mo-containing sol–gel, including 1% tungsten (W). Atomic-resolution electron microscopy characterization reveals that small tungsten oxide clusters are commonly present on the as-grown MoS 2 film due to themore » incomplete reduction of W precursor at the reaction temperature. These omnipresent small tungsten oxide clusters contribute to the p-type behavior, as verified by density functional theory calculations, while preserving the crystallinity of the MoS 2 atomic layers. The Mo containing sol–gel precursor is compatible with the soft-lithography techniques, which enables patterned growth of p-type MoS 2 atomic layers into regular arrays with different shapes, holding great promise for highly integrated device applications. Lastly, an atomically thin p–n junction is fabricated by the as-prepared MoS 2, which shows strong rectifying behavior.« less

Patterned growth of p-type MoS 2 atomic layers using sol-gel as precursor

DOE PAGES

Zheng, Wei; Lin, Junhao; Feng, Wei; ...

2016-07-19

2D layered MoS 2 has drawn intense attention for its applications in flexible electronic, optoelectronic, and spintronic devices. Most of the MoS 2 atomic layers grown by conventional chemical vapor deposition techniques are n-type due to the abundant sulfur vacancies. Facile production of MoS 2 atomic layers with p-type behavior, however, remains challenging. Here, a novel one-step growth has been developed to attain p-type MoS 2 layers in large scale by using Mo-containing sol–gel, including 1% tungsten (W). Atomic-resolution electron microscopy characterization reveals that small tungsten oxide clusters are commonly present on the as-grown MoS 2 film due to themore » incomplete reduction of W precursor at the reaction temperature. These omnipresent small tungsten oxide clusters contribute to the p-type behavior, as verified by density functional theory calculations, while preserving the crystallinity of the MoS 2 atomic layers. The Mo containing sol–gel precursor is compatible with the soft-lithography techniques, which enables patterned growth of p-type MoS 2 atomic layers into regular arrays with different shapes, holding great promise for highly integrated device applications. Lastly, an atomically thin p–n junction is fabricated by the as-prepared MoS 2, which shows strong rectifying behavior.« less

Botulinum toxin decreases hyperalgesia and inhibits P2X3 receptor over-expression in sensory neurons induced by ventral root transection in rats.

PubMed

Xiao, Lizu; Cheng, Jianguo; Dai, Juanli; Zhang, Deren

2011-09-01

We aim to determine the effects of Botulinum toxin type A (BTX-A) on neuropathic pain behavior and the expression of P2X(3) receptor in dorsal root ganglion (DRG) in rats with neuropathic pain induced by L5 ventral root transection (L5 VRT). Neuropathic pain was induced by L5 VRT in male Sprague-Dawley rats. Either saline or BTX-A was administered to the plantar surface. Behavioral tests were conducted preoperatively and at predefined postoperative days. The expression of P2X(3) receptors in DRG neurons was detected by immunoreactivity at postoperative days 3, 7, 14, and 21. The number of positive P2X(3) neurons in the ipsilateral L5 DRG increased significantly after L5 VRT (P<0.001). This increase persisted for at least 3 weeks after the operation. No significant changes in P2X(3) expression were detected in the contralateral L5, or in the L4 DRGs bilaterally. Subcutaneous administration of BTX-A, performed on the left hindpaw at days 4, 8, or 16 post VRT surgery, significantly reduced mechanical allodynia bilaterally and inhibited P2X(3) over-expression induced by L5 VRT. L5 VRT led to over-expression of P2X(3) receptors in the L5 DRG and bilateral mechanical allodynia in rats. Subcutaneous injection of BTX-A significantly reversed the neuropathic pain behavior and the over-expression of P2X(3) receptor in nociceptive neurons. These data not only show over-expression of purinergic receptors in the VRT model of neuropathic pain but also reveal a novel mechanism of botulinum toxin action on nociceptive neurons. Wiley Periodicals, Inc.

Pharmacologic Treatment Assigned for Niemann Pick Type C1 Disease Partly Changes Behavioral Traits in Wild-Type Mice.

PubMed

Schlegel, Victoria; Thieme, Markus; Holzmann, Carsten; Witt, Martin; Grittner, Ulrike; Rolfs, Arndt; Wree, Andreas

2016-11-09

Niemann-Pick Type C1 (NPC1) is an autosomal recessive inherited disorder characterized by accumulation of cholesterol and glycosphingolipids. Previously, we demonstrated that BALB/c-npc1 nih Npc1 -/- mice treated with miglustat, cyclodextrin and allopregnanolone generally performed better than untreated Npc1 -/- animals. Unexpectedly, they also seemed to accomplish motor tests better than their sham-treated wild-type littermates. However, combination-treated mutant mice displayed worse cognition performance compared to sham-treated ones. To evaluate effects of these drugs in healthy BALB/c mice, we here analyzed pharmacologic effects on motor and cognitive behavior of wild-type mice. For combination treatment mice were injected with allopregnanolone/cyclodextrin weekly, starting at P7. Miglustat injections were performed daily from P10 till P23. Starting at P23, miglustat was embedded in the chow. Other mice were treated with miglustat only, or sham-treated. The battery of behavioral tests consisted of accelerod, Morris water maze, elevated plus maze, open field and hot-plate tests. Motor capabilities and spontaneous motor behavior were unaltered in both drug-treated groups. Miglustat-treated wild-type mice displayed impaired spatial learning compared to sham- and combination-treated mice. Both combination- and miglustat-treated mice showed enhanced anxiety in the elevated plus maze compared to sham-treated mice. Additionally, combination treatment as well as miglustat alone significantly reduced brain weight, whereas only combination treatment reduced body weight significantly. Our results suggest that allopregnanolone/cyclodextrin ameliorate most side effects of miglustat in wild-type mice.

Temperature-dependent thermal and thermoelectric properties of n -type and p -type S c1 -xM gxN

NASA Astrophysics Data System (ADS)

Saha, Bivas; Perez-Taborda, Jaime Andres; Bahk, Je-Hyeong; Koh, Yee Rui; Shakouri, Ali; Martin-Gonzalez, Marisol; Sands, Timothy D.

2018-02-01

Scandium Nitride (ScN) is an emerging rocksalt semiconductor with octahedral coordination and an indirect bandgap. ScN has attracted significant attention in recent years for its potential thermoelectric applications, as a component material in epitaxial metal/semiconductor superlattices, and as a substrate for defect-free GaN growth. Sputter-deposited ScN thin films are highly degenerate n -type semiconductors and exhibit a large thermoelectric power factor of ˜3.5 ×10-3W /m -K2 at 600-800 K. Since practical thermoelectric devices require both n- and p-type materials with high thermoelectric figures-of-merit, development and demonstration of highly efficient p-type ScN is extremely important. Recently, the authors have demonstrated p-type S c1 -xM gxN thin film alloys with low M gxNy mole-fractions within the ScN matrix. In this article, we demonstrate temperature dependent thermal and thermoelectric transport properties, including large thermoelectric power factors in both n- and p-type S c1 -xM gxN thin film alloys at high temperatures (up to 850 K). Employing a combination of temperature-dependent Seebeck coefficient, electrical conductivity, and thermal conductivity measurements, as well as detailed Boltzmann transport-based modeling analyses of the transport properties, we demonstrate that p-type S c1 -xM gxN thin film alloys exhibit a maximum thermoelectric power factor of ˜0.8 ×10-3W /m -K2 at 850 K. The thermoelectric properties are tunable by adjusting the M gxNy mole-fraction inside the ScN matrix, thereby shifting the Fermi energy in the alloy films from inside the conduction band in case of undoped n -type ScN to inside the valence band in highly hole-doped p -type S c1 -xM gxN thin film alloys. The thermal conductivities of both the n- and p-type films were found to be undesirably large for thermoelectric applications. Thus, future work should address strategies to reduce the thermal conductivity of S c1 -xM gxN thin-film alloys, without affecting the power factor for improved thermoelectric performance.

Relationship between perceived social support and self-care behavior in type 2 diabetics: A cross-sectional study

PubMed Central

Mohebi, Siamak; Parham, Mahmoud; Sharifirad, Gholamreza; Gharlipour, Zabihollah; Mohammadbeigi, Abolfazl; Rajati, Fatemeh

2018-01-01

BACKGROUND: Social support is one of the most effective factors on the diabetic self-care. This study aimed to assess social support and its relationship to self-care in type 2 diabetic patients in Qom, Iran. STUDY DESIGN: A cross-sectional study was conducted on 325 diabetics attending the Diabetes Mellitus Association. METHODS: Patients who meet inclusion and exclusion criteria were selected using random sampling method. Data were collected by the Summary of Diabetes Self-Care Activities and Multidimensional Scale of Perceived Social Support, with hemoglobin A1C test. Data were analyzed using descriptive statistics and independent t-test, analysis of variance, Pearson correlation, and linear regression test, using 0.05 as the critical significance level, provided by SPSS software. RESULTS: The mean and standard deviation of self-care and social support scores were 4.31 ± 2.7 and 50.32 ± 11.09, respectively. The mean level of glycosylated hemoglobin (HbA1C) of patients was 7.54. There was a significant difference between mean score of self-care behaviors and social support according to gender and marital status (P < 0.05). The regression analysis showed that disease duration was the only variable which had a significant effect on the level of HbA1C (P < 0.001). Pearson correlation coefficient indicated that self-care and social support significantly correlated (r = 0.489, P > 0.001) and also predictive power of social support was 0.28. Self-care was significantly better in diabetics with HbA1C ≤7%. Patients who had higher HbA1C felt less, but not significant, social support. CONCLUSIONS: This study indicated the relationship between social support and self-care behaviors in type 2 diabetic patients. Interventions that focus on improving the social support and self-care of diabetic control may be more effective in improving glycemic control. PMID:29693029

Relationship between perceived social support and self-care behavior in type 2 diabetics: A cross-sectional study.

PubMed

Mohebi, Siamak; Parham, Mahmoud; Sharifirad, Gholamreza; Gharlipour, Zabihollah; Mohammadbeigi, Abolfazl; Rajati, Fatemeh

2018-01-01

Social support is one of the most effective factors on the diabetic self-care. This study aimed to assess social support and its relationship to self-care in type 2 diabetic patients in Qom, Iran. A cross-sectional study was conducted on 325 diabetics attending the Diabetes Mellitus Association. Patients who meet inclusion and exclusion criteria were selected using random sampling method. Data were collected by the Summary of Diabetes Self-Care Activities and Multidimensional Scale of Perceived Social Support, with hemoglobin A 1 C test. Data were analyzed using descriptive statistics and independent t -test, analysis of variance, Pearson correlation, and linear regression test, using 0.05 as the critical significance level, provided by SPSS software. The mean and standard deviation of self-care and social support scores were 4.31 ± 2.7 and 50.32 ± 11.09, respectively. The mean level of glycosylated hemoglobin (HbA 1 C) of patients was 7.54. There was a significant difference between mean score of self-care behaviors and social support according to gender and marital status ( P < 0.05). The regression analysis showed that disease duration was the only variable which had a significant effect on the level of HbA 1 C ( P < 0.001). Pearson correlation coefficient indicated that self-care and social support significantly correlated ( r = 0.489, P > 0.001) and also predictive power of social support was 0.28. Self-care was significantly better in diabetics with HbA 1 C ≤7%. Patients who had higher HbA 1 C felt less, but not significant, social support. This study indicated the relationship between social support and self-care behaviors in type 2 diabetic patients. Interventions that focus on improving the social support and self-care of diabetic control may be more effective in improving glycemic control.

An analysis of fat-related and fiber-related behavior in men and women with type 2 diabetes mellitus: key findings for clinical practice.

PubMed

Hendrychova, Tereza; Vytrisalova, Magda; Vlcek, Jiri; Smahelova, Alena; Kubena, Ales Antonin

2013-01-01

Despite the efforts of health care providers, adherence of patients with type 2 diabetes to the recommended diet is poor. The aim of this study was to describe the eating habits with emphasis on fat and fiber-related behavior (FFB) as well as the relationship between FFB behavior and parameters of diabetes control in men and women with type 2 diabetes mellitus. The subjects in this observational cross-sectional study were 200 patients (54.5% male, mean age 66.2 ± 10.1 years, mean Diabetes Control and Complications Trial [DDCT] glycosylated hemoglobin [HbA1c] 7.6% ± 1.7%) recruited from diabetes outpatient clinics in the Czech Republic. The subjects filled out the Fat- and Fiber-related Diet Behavior Questionnaire. The most recent patient data on diabetes control and drug therapy were derived from patient medical records. Patients tend to modify the dishes they are used to, rather than remove them completely from their diet and replace them by other types of foods. It is easier to perform healthier fat-related behaviors than fiber-related ones. Women scored significantly better than men on the fat-related diet habits summary scale (P = 0.002), as well as on "modify meat" (P = 0.001) and "substitute specially manufactured low-fat foods" (P = 0.045) subscales. A better score on the fat-related diet habits summary scale was significantly associated with higher HbA1c (ρ = -0.248; P = 0.027) and higher waist circumference (ρ = -0.254; P = 0.024) in women. Type 2 diabetes patients are likely to vary in their FFB behavior, and their dietary habits depend on gender. Health care professionals should pay attention to these facts when providing specific education. Emphasis should be placed on how to increase the fiber intake in diabetic patients.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sturza, Mihai; Bugaris, Daniel E.; Malliakas, Christos D.

The new ternary copper selenide NaCu 4Se 3 crystallizes in the RbCd 4As 3 structure type with the trigonal space group R3m and lattice constants a = 4.0316(4) angstrom and c = 31.438(8) angstrom. Its structure is built from two-dimensional slabs of 2 ∞ [Cu 4Se 3] separated by Na + cations. The compound is formally mixed-valent with Se 2-/Se - atoms and exhibits metallic properties. It is a hole conductor with an electrical conductivity of similar to 300 S cm -1 at room temperature and a thermopower of similar to 10 mu V K -1. Hall effect measurements indicatemore » holes as the dominant carrier with a concentration of similar to 6.12(1) X 10 21 cm -3 at 300 K. Density functional theory electronic structure calculations indicate p -type metallic behavior for the 2 ∞ [Cu 4Se 3] framework, which is in a good agreement with the experimental metallic conductivity and Pauli paramagnetism.« less

Flow Accelerated Corrosion of Carbon Steel in the Feedwater System of PWR Plants - Behaviour of Welds and Weld Assemblies

NASA Astrophysics Data System (ADS)

Mansour, C.; Pavageau, E. M.; Faucher, A.; Inada, F.; Yoneda, K.; Miller, C.; Bretelle, J.-L.

Flow Accelerated Corrosion (FAC) of carbon steel is a phenomenon that has been studied for many years. However, to date, the specific behavior of welds and weld assemblies of carbon steel towards this phenomenon has been scarcely examined. An experimental program of FAC of welds and weld assemblies is being conducted by EDF and CRIEPI. This paper describes the results obtained on the behavior of weld metal independently of its behavior in a weld assembly as well as the sensitivity to FAC of various weld assembly configurations. Tests are performed, at EDF, in the CIROCO loop which permits to follow the FAC rate by gammametry measurements, and at CRIEPI, in the PRINTEMPS loop where FAC is measured by laser displacement sensor. Welds are performed by two different methods: Submerged Arc Welding (SAW) and Gas Tungsten Arc Welding (GTAW). The influence of several parameters on FAC of welds is examined: welding method, chromium content and temperature. For weld assemblies, only the impact of chromium content is studied. All the tests are conducted in ammonia medium at pH 9.0 and oxygen concentration lower then 1 ppb. Chemical parameters, as the pH, the conductivity and oxygen concentration, are measured in situ during the test and surface characterizations are performed after the test. The results show that, with more than 0.15% chromium, no FAC is detected on the weld metal, which is similar to the base metal behaviour. For the same and lower chromium content, the two types of metal have the same FAC rate. Concerning the temperature effect, for both metals FAC rate decreases with temperature increase above 150°C. Below 150 °C, their behaviour seems to be different. For weld assemblies, the study of different configurations shows that the chromium content is the main parameter affecting the behaviour of the specimens. Additional tests and modeling studies will be conducted in order to complete the results.

Student nurses' unethical behavior, social media, and year of birth.

PubMed

Smith, Gloria Copeland; Knudson, Troy Keith

2016-12-01

This study is the result of findings from a previous dissertation conducted by this author on Student Nurses' Unethical Behavior, Boundaries, and Social Media. The use of social media can be detrimental to the nurse-patient relationship if used in an unethical manner. A mixed method, using a quantitative approach based on research questions that explored differences in student nurses' unethical behavior by age (millennial vs nonmillennial) and clinical cohort, the relationship of unethical behavior to the utilization of social media, and analysis on year of birth and unethical behavior. A qualitative approach was used based on a guided faculty interview and common themes of student nurses' unethical behavior. Participants and Research Context: In total, 55 Associate Degree nursing students participated in the study; the research was conducted at Central Texas College. There were eight faculty-guided interviews. Ethical considerations: The main research instrument was an anonymous survey. All participants were assured of their right to an informed consent. All participants were informed of the right to withdraw from the study at any time. Findings indicate a significant correlation between student nurses' unethical behavior and use of social media (p = 0.036) and a significant difference between student unethical conduct by generation (millennials vs nonmillennials (p = 0.033)) and by clinical cohort (p = 0.045). Further findings from the follow-up study on year of birth and student unethical behavior reveal a correlation coefficient of 0.384 with a significance level of 0.003. Surprisingly, the study found that second-semester students had less unethical behavior than first-, third-, and fourth-semester students. The follow-up study found that this is because second-semester students were the oldest cohort. Implications for positive social change for nursing students include improved ethics education that may motivate ethical conduct throughout students' careers nationally and globally for better understanding and promotion of ethics and behavior.

Structural and electrical properties of cobalt-doped 4H-SrMnO_{3-δ} perovskites obtained by the hydrothermal method

NASA Astrophysics Data System (ADS)

ben Rguiga, N.; Álvarez-Serrano, I.; López, M. L.; Chérif, W.; Alonso, J. A.

2018-02-01

A mild hydrothermal method was adapted to prepare the SrMn_{1-x}CoxO_{3-δ} (0 ≤ x ≤ 0.2) compounds. They showed hexagonal-4H perovskite-type structure with space group P63/mmc, and cell parameters a ˜ 5.45 and c ˜ 9.08 Å, as deduced from X-ray and neutron diffraction data. The mean atomic concentrations indicated global stoichiometries close to the nominal ones whereas electron microscopy analyses pointed out to heterogeneity at the nanoscale. The characterization of the electrical response by means of impedance measurements, suggested a semiconductor behavior mainly ascribed to bulk contributions. Relaxation and conduction processes were analyzed. The materials showed mixed electronic-ionic conduction above ˜ 400 K, when ionic conduction between intergrains becomes favored. Microstructural homogeneity was revealed as the key factor controlling the electrical response.

Using Three-Dimensional Fluorescence Spectrum Technology to Analyze the Effects of Natural Dissolved Organic Matter on the Pesticide Residues in the Soil.

PubMed

Lei, Hong-jun; Han, Yu-ping; Liu, Xin; Xu, Jian-xin

2015-07-01

The behavior of pesticide in soil is influenced by dissolved organic matter (DOM) through competition adsorption, adsorption, solubilization, accelerated degradation, and so on. Thus DOM and its components play an important role in the environmental risk in the soil ecosystem and groundwater environment. Currently, most studies focused on the short-term effect of high concentration of DOM on the pesticide residues. However, soil DOM is mainly at low level. Therefore, there is of some practical significance to probe into the environmental behavior of soil pesticides under natural level of DOM. Thus a site investigation was conducted in the farmland with long-term application history of pesticide. By using the three dimensional excitation-emission fluorescence matrix (3D-EEM) technology, together with the fluorescence regional integration (FRI) quantitative method, the long-term effects of pesticide residues under low concentration of natural DOM were analyzed. Results showed that: (1) The long-term effects of the natural DOM components on the environment behavior of most soil organochlorine pesticides were not significant except for a few pesticides such as y-HCH, p, p'-DDE, etc. (2) The influencing effects of DOM components on different type of pesticides were varied. Among which, the content of tyrosine component showed a significantly negative correlation (p < 0.05) with the concentration of y-HCH and p, p'-DDE. There were significant positive correlations (p < 0.05) between the byproducts of microbial degradation in DOM components and the concentration of heptachlor. There were also a significant positive correlation (p < 0.05) between the content of active humus component of humic acid in the DOM and the concentration of heptachlor epoxide. These results suggested that the distribution of different types of pesticides residue in the soil was influenced by different components at different levels of significance. (3) The humification degree of soil organic matter showed minor effect of DOM on the pesticide residues in the soil. In this study, 3D-EEM and FRI technology were firstly coupled in use for studying the influence of different components of DOM in soil on the environmental behavior of pesticides, which provides a new idea for the research on the mechanism of pesticides transportation and transformation in soil and groundwater environment.

n/p-Type changeable semiconductor TiO2 prepared from NTA

NASA Astrophysics Data System (ADS)

Li, Qiuye; Wang, Xiaodong; Jin, Zhensheng; Yang, Dagang; Zhang, Shunli; Guo, Xinyong; Yang, Jianjun; Zhang, Zhijun

2007-10-01

A novel kind of nano-sized TiO2 (anatase) was obtained by high-temperature (400-700°C) dehydration of nanotube titanic acid (H2Ti2O4(OH)2, NTA). The high-temperature (400-700°C) dehydrated nanotube titanic acids (HD-NTAs) with a unique defect structure exhibited a p-type semiconductor behavior under visible-light irradiation (λ≥420 nm, E photon=2.95 eV), whereas exhibited an n-type semiconductor behavior irradiated with UV light (λ=365 nm, E photon=3.40 eV).

Community Trial on Heat Related-Illness Prevention Behaviors and Knowledge for the Elderly

PubMed Central

Takahashi, Noriko; Nakao, Rieko; Ueda, Kayo; Ono, Masaji; Kondo, Masahide; Honda, Yasushi; Hashizume, Masahiro

2015-01-01

This study aims to explore whether broadcasting heat health warnings (HHWs), to every household and whether the additional home delivery of bottled water labeled with messages will be effective in improving the behaviors and knowledge of elderly people to prevent heat-related illness. A community trial on heat-related-illness-prevention behaviors and knowledge for people aged between 65 and 84 years was conducted in Nagasaki, Japan. Five hundred eight subjects were selected randomly from three groups: heat health warning (HHW), HHW and water delivery (HHW+W), and control groups. Baseline and follow-up questionnaires were conducted in June and September 2012, respectively. Of the 1524 selected subjects, the 1072 that completed both questionnaires were analyzed. The HHW+W group showed improvements in nighttime AC use (p = 0.047), water intake (p = 0.003), cooling body (p = 0.002) and reduced activities in heat (p = 0.047) compared with the control, while the HHW group improved hat or parasol use (p = 0.008). An additional effect of household water delivery was observed in water intake (p = 0.067) and cooling body (p = 0.095) behaviors. HHW and household bottled water delivery improved heat-related-illness-prevention behaviors. The results indicate that home water delivery in addition to a HHW may be needed to raise awareness of the elderly. PMID:25789456

Electrical Investigation of Nanostructured Fe2O3/p-Si Heterojunction Diode Fabricated Using the Sol-Gel Technique

NASA Astrophysics Data System (ADS)

Mansour, Shehab A.; Ibrahim, Mervat M.

2017-11-01

Iron oxide (α-Fe2O3) nanocrystals have been synthesized via the sol-gel technique. The structural and morphological features of these nanocrystals were studied using x-ray diffraction, Fourier transform-infrared spectroscopy and transmission electron microscopy. Colloidal solution of synthesized α-Fe2O3 (hematite) was spin-coated onto a single-crystal p-type silicon (p-Si) wafer to fabricate a heterojunction diode with Mansourconfiguration Ag/Fe2O3/p-Si/Al. This diode was electrically characterized at room temperature using current-voltage (I-V) characteristics in the voltage range from -9 V to +9 V. The fabricated diode showed a good rectification behavior with a rectification factor 1.115 × 102 at 6 V. The junction parameters such as ideality factor, barrier height, series resistance and shunt resistance are determined using conventional I-V characteristics. For low forward voltage, the conduction mechanism is dominated by the defect-assisted tunneling process with conventional electron-hole recombination. However, at higher voltage, I-V ohmic and space charge-limited current conduction was became less effective with the contribution of the trapped-charge-limited current at the highest voltage range.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Dehua; Liu, Qing; Tisdale, Jeremy

This paper reports Seebeck effects driven by both surface polarization difference and entropy difference by using intramolecular charge-transfer states in n-type and p-type conjugated polymers, namely IIDT and IIDDT, based on vertical conductor/polymer/conductor thin-film devices. Large Seebeck coefficients of -898 V/K and 1300 V/K from are observed from n-type IIDT p-type IIDDT, respectively, when the charge-transfer states are generated by a white light illumination of 100 mW/cm2. Simultaneously, electrical conductivities are increased from almost insulating states in dark condition to conducting states under photoexcitation in both n-type IIDT and p-type IIDDT devices. We find that the intramolecular charge-transfer states canmore » largely enhance Seebeck effects in the n-type IIDT and p-type IIDDT devices driven by both surface polarization difference and entropy difference. Furthermore, the Seebeck effects can be shifted between polarization and entropy regimes when electrical conductivities are changed. This reveals a new concept to develop Seebeck effects by controlling polarization and entropy regimes based on charge-transfer states in vertical conductor/polymer/conductor thin-film devices.« less

Influence of the transition region between p- and n-type polycrystalline silicon passivating contacts on the performance of interdigitated back contact silicon solar cells

NASA Astrophysics Data System (ADS)

Reichel, Christian; Müller, Ralph; Feldmann, Frank; Richter, Armin; Hermle, Martin; Glunz, Stefan W.

2017-11-01

Passivating contacts based on thin tunneling oxides (SiOx) and n- and p-type semi-crystalline or polycrystalline silicon (poly-Si) enable high passivation quality and low contact resistivity, but the integration of these p+/n emitter and n+/n back surface field junctions into interdigitated back contact silicon solar cells poses a challenge due to high recombination at the transition region from p-type to n-type poly-Si. Here, the transition region was created in different configurations—(a) p+ and n+ poly-Si regions are in direct contact with each other ("pn-junction"), using a local overcompensation (counterdoping) as a self-aligning process, (b) undoped (intrinsic) poly-Si remains between the p+ and n+ poly-Si regions ("pin-junction"), and (c) etched trenches separate the p+ and n+ poly-Si regions ("trench")—in order to investigate the recombination characteristics and the reverse breakdown behavior of these solar cells. Illumination- and injection-dependent quasi-steady state photoluminescence (suns-PL) and open-circuit voltage (suns-Voc) measurements revealed that non-ideal recombination in the space charge regions with high local ideality factors as well as recombination in shunted regions strongly limited the performance of solar cells without a trench. In contrast, solar cells with a trench allowed for open-circuit voltage (Voc) of 720 mV, fill factor of 79.6%, short-circuit current (Jsc) of 41.3 mA/cm2, and a conversion efficiencies (η) of 23.7%, showing that a lowly conducting and highly passivating intermediate layer between the p+ and n+ poly-Si regions is mandatory. Independent of the configuration, no hysteresis was observed upon multiple stresses in reverse direction, indicating a controlled and homogeneously distributed breakdown, but with different breakdown characteristics.

[The link between aggressive behavior and depression in adolescence. A cross-sectional study conducted in the psychiatric emergency unit at the Sainte-Anne hospital].

PubMed

Benarous, X; Guedj, M J; Braitman, A; Gallois, E; Lana, P

2014-12-01

The link between depression and aggressive behavior in adults has been found in many studies. In adolescents, this relationship is still controversial. Several studies point out that irritability is a key symptom in adolescent depressed. Few studies have analyzed precisely the kind of aggressive behavior. This study sets out to assess the relationship between aggressive behavior and depressive affects in adolescents. We also pay attention in this population to hopelessness feelings, anxiety, global functioning and the type of aggressive behavior. This is a descriptive and observational cross-sectional study. Data was collected from 49 successive adolescents admitted for a 24-hour evaluation in the emergency department of the Sainte-Anne psychiatric hospital. The inclusion period was from February to April 2012, with age limits between 15 and 18. For each patient, the clinician completed with the parents or other caregivers the Modified Overt Aggressive Scale (MOAS) searching for existence of aggressive behavior in the week prior to the consultation. The population was divided into two groups: P- group when the MOAS score was < 3 and the P+ group when the MOAS score was ≥ 3. The Global Assessment of Functioning Scale and Adolescent Depression Rating Scale for clinicians (ADRSc) were also completed. Each patient completed the self-report Buss-Perry Aggression Questionnaire (QA), the Beck Hopelessness scale and the Adolescent Depression Rating Scale for patients (ADRSp). Forty-nine adolescents with a median age of 16 years and 4 months participated. The first reason for consultation was depressive symptoms, followed by disruptive behavior. The analysis was conducted on 39 questionnaires. The demographic profile of the two groups was similar. We did not find any significant difference between the groups P+ and P- on ADRSc scores and secondary criteria. However, we found higher scores in the QA in the more depressed patient, especially a higher hostility score in this sample. In the subgroup analysis: as expected self-aggressive behavior was associated with a higher depression score, more hospitalization and a poor global functioning score. Surprisingly, the patients who showed physical aggression against others had a better prognosis and lower depression scores. The study did not conclude on the link between aggressive behavior and depression in this population. The adolescent hostility appears more characteristic of depression compared to other dimensions of aggressivity (anger, verbal aggression, physical aggression) in adolescents. Physical aggression against others appeared not only less typical in depression but was also associated with a better global functioning. Clinicians should pay particular attention to the kind of aggressive behavior in clinical evaluations of adolescents in an emergency context. Copyright © 2014 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

Directionality Between Tolerance of Deviance and Deviant Behavior is Age-Moderated in Chronically Stressed Youth

PubMed Central

Ridenour, TY A.; Caldwell, Linda L.; Coatsworth, J. Douglas; Gold, Melanie A.

2011-01-01

Problem behavior theory posits that tolerance of deviance is an antecedent to antisocial behavior and substance use. In contrast, cognitive dissonance theory implies that acceptability of a behavior may increase after experiencing the behavior. Using structural equation modeling, this investigation tested whether changes in tolerance of deviance precede changes in conduct disorder criteria or substance use or vice versa, or if they change concomitantly. Two-year longitudinal data from 246 8- to 16-year-olds suggested that tolerance of deviance increases after conduct disorder criteria or substance use in 8-to-10- and 11-to-12-year-olds. These results were consistent with cognitive dissonance theory. In 13-to-16- year-olds, no directionality was suggested, consistent with neither theory. These results were replicated in boys and girls and for different types of conduct disorder criteria aggression (covert behavior), deceitfulness and vandalism (overt behavior), and serious rule-breaking (authority conflict). The age-specific directionality between tolerance of deviance and conduct disorder criteria or substance use is consistent with unique etiologies between early onset versus adolescent-onset subtypes of behavior problems. PMID:22180721

Directionality Between Tolerance of Deviance and Deviant Behavior is Age-Moderated in Chronically Stressed Youth.

PubMed

Ridenour, Ty A; Caldwell, Linda L; Coatsworth, J Douglas; Gold, Melanie A

2011-03-20

Problem behavior theory posits that tolerance of deviance is an antecedent to antisocial behavior and substance use. In contrast, cognitive dissonance theory implies that acceptability of a behavior may increase after experiencing the behavior. Using structural equation modeling, this investigation tested whether changes in tolerance of deviance precede changes in conduct disorder criteria or substance use or vice versa, or if they change concomitantly. Two-year longitudinal data from 246 8- to 16-year-olds suggested that tolerance of deviance increases after conduct disorder criteria or substance use in 8-to-10- and 11-to-12-year-olds. These results were consistent with cognitive dissonance theory. In 13-to-16- year-olds, no directionality was suggested, consistent with neither theory. These results were replicated in boys and girls and for different types of conduct disorder criteria aggression (covert behavior), deceitfulness and vandalism (overt behavior), and serious rule-breaking (authority conflict). The age-specific directionality between tolerance of deviance and conduct disorder criteria or substance use is consistent with unique etiologies between early onset versus adolescent-onset subtypes of behavior problems.

Impact of Game-Inspired Infographics on User Engagement and Information Processing in an eHealth Program

PubMed Central

Qian, Xiaokun; Deal, Allison M; Ribisl, Kurt M; Linnan, Laura A; Tate, Deborah F

2016-01-01

Background Online interventions providing individual health behavior assessment should deliver feedback in a way that is both understandable and engaging. This study focused on the potential for infographics inspired by the aesthetics of game design to contribute to these goals. Objective We conducted formative research to test game-inspired infographics against more traditional displays (eg, text-only, column chart) for conveying a behavioral goal and an individual’s behavior relative to the goal. We explored the extent to which the display type would influence levels of engagement and information processing. Methods Between-participants experiments compared game-inspired infographics with traditional formats in terms of outcomes related to information processing (eg, comprehension, cognitive load) and engagement (eg, attitudes toward the information, emotional tone). We randomly assigned participants (N=1162) to an experiment in 1 of 6 modules (tobacco use, alcohol use, vegetable consumption, fruit consumption, physical activity, and weight management). Results In the tobacco module, a game-inspired format (scorecard) was compared with text-only; there were no differences in attitudes and emotional tone, but the scorecard outperformed text-only on comprehension (P=.004) and decreased cognitive load (P=.006). For the other behaviors, we tested 2 game-inspired formats (scorecard, progress bar) and a traditional column chart; there were no differences in comprehension, but the progress bar outperformed the other formats on attitudes and emotional tone (P<.001 for all contrasts). Conclusions Across modules, a game-inspired infographic showed potential to outperform a traditional format for some study outcomes while not underperforming on other outcomes. Overall, findings support the use of game-inspired infographics in behavioral assessment feedback to enhance comprehension and engagement, which may lead to greater behavior change. PMID:27658469

Impact of Game-Inspired Infographics on User Engagement and Information Processing in an eHealth Program.

PubMed

Comello, Maria Leonora G; Qian, Xiaokun; Deal, Allison M; Ribisl, Kurt M; Linnan, Laura A; Tate, Deborah F

2016-09-22

Online interventions providing individual health behavior assessment should deliver feedback in a way that is both understandable and engaging. This study focused on the potential for infographics inspired by the aesthetics of game design to contribute to these goals. We conducted formative research to test game-inspired infographics against more traditional displays (eg, text-only, column chart) for conveying a behavioral goal and an individual's behavior relative to the goal. We explored the extent to which the display type would influence levels of engagement and information processing. Between-participants experiments compared game-inspired infographics with traditional formats in terms of outcomes related to information processing (eg, comprehension, cognitive load) and engagement (eg, attitudes toward the information, emotional tone). We randomly assigned participants (N=1162) to an experiment in 1 of 6 modules (tobacco use, alcohol use, vegetable consumption, fruit consumption, physical activity, and weight management). In the tobacco module, a game-inspired format (scorecard) was compared with text-only; there were no differences in attitudes and emotional tone, but the scorecard outperformed text-only on comprehension (P=.004) and decreased cognitive load (P=.006). For the other behaviors, we tested 2 game-inspired formats (scorecard, progress bar) and a traditional column chart; there were no differences in comprehension, but the progress bar outperformed the other formats on attitudes and emotional tone (P<.001 for all contrasts). Across modules, a game-inspired infographic showed potential to outperform a traditional format for some study outcomes while not underperforming on other outcomes. Overall, findings support the use of game-inspired infographics in behavioral assessment feedback to enhance comprehension and engagement, which may lead to greater behavior change.

Behavioral self-concept as predictor of teen drinking behaviors.

PubMed

Dudovitz, Rebecca N; Li, Ning; Chung, Paul J

2013-01-01

Adolescence is a critical developmental period for self-concept (role identity). Cross-sectional studies link self-concept's behavioral conduct domain (whether teens perceive themselves as delinquent) with adolescent substance use. If self-concept actually drives substance use, then it may be an important target for intervention. In this study, we used longitudinal data from 1 school year to examine whether behavioral self-concept predicts teen drinking behaviors or vice versa. A total of 291 students from a large, predominantly Latino public high school completed a confidential computerized survey in the fall and spring of their 9th grade year. Survey measures included the frequency of alcohol use, binge drinking and at-school alcohol use in the previous 30 days; and the Harter Self-Perception Profile for Adolescents behavioral conduct subscale. Multiple regressions were performed to test whether fall self-concept predicted the frequency and type of spring drinking behavior, and whether the frequency and type of fall drinking predicted spring self-concept. Fall behavioral self-concept predicted both the frequency and type of spring drinking. Students with low versus high fall self-concept had a predicted probability of 31% versus 20% for any drinking, 20% versus 8% for binge drinking and 14% versus 4% for at-school drinking in the spring. However, neither the frequency nor the type of fall drinking significantly predicted spring self-concept. Low behavioral self-concept may precede or perhaps even drive adolescent drinking. If these results are confirmed, then prevention efforts might be enhanced by targeting high-risk teens for interventions that help develop a healthy behavioral self-concept. Copyright © 2013 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

DDT Behavior of Waxed Mixtures of RDX, HMX, and Tetryl

DTIC Science & Technology

1977-10-18

HMX (689*; Class A, 6 ’ 200p), RDX (659; Class E, 6 P 15p), tetryl (812; 6 s 470p), carnauba wax (134; 6 r 125p). The mixing procedure was that used...NSWC/WOL TR 77-96 O DDT BEHAVIOR OF WAXED MIXTURES OF " RDX, HMX, AND TETRYL BY DONNA PRICE and RICHARD R. BERNECKER RESEARCH AND TECHNOLOGY...BEFORE COMPLETING FORM RY PORT NUM ER 2. GOVT ACCESSION No. 3. RECIPIENT’S CATALOG NUMBER S. TYPE OF REPORT & PERIOD COVERED PDT Behavior of Waxed Mixtures

Functional zinc oxide nanostructures for electronic and energy applications

NASA Astrophysics Data System (ADS)

Prasad, Abhishek

ZnO has proven to be a multifunctional material with important nanotechnological applications. ZnO nanostructures can be grown in various forms such as nanowires, nanorods, nanobelts, nanocombs etc. In this work, ZnO nanostructures are grown in a double quartz tube configuration thermal Chemical Vapor Deposition (CVD) system. We focus on functionalized ZnO Nanostructures by controlling their structures and tuning their properties for various applications. The following topics have been investigated: (1) We have fabricated various ZnO nanostructures using a thermal CVD technique. The growth parameters were optimized and studied for different nanostructures. (2) We have studied the application of ZnO nanowires (ZnONWs) for field effect transistors (FETs). Unintentional n-type conductivity was observed in our FETs based on as-grown ZnO NWs. We have then shown for the first time that controlled incorporation of hydrogen into ZnO NWs can introduce p-type characters to the nanowires. We further found that the n-type behaviors remained, leading to the ambipolar behaviors of hydrogen incorporated ZnO NWs. Importantly, the detected p- and n- type behaviors are stable for longer than two years when devices were kept in ambient conditions. All these can be explained by an ab initio model of Zn vacancy-Hydrogen complexes, which can serve as the donor, acceptors, or green photoluminescence quencher, depend on the number of hydrogen atoms involved. (3) Next ZnONWs were tested for electron field emission. We focus on reducing the threshold field (Eth) of field emission from non-aligned ZnO NWs. As encouraged by our results on enhancing the conductivity of ZnO NWs by hydrogen annealing described in Chapter 3, we have studied the effect of hydrogen annealing for improving field emission behavior of our ZnO NWs. We found that optimally annealed ZnO NWs offered much lower threshold electric field and improved emission stability. We also studied field emission from ZnO NWs at moderate vacuum levels. We found that there exists a minimum Eth as we scale the threshold field with pressure. This behavior is explained by referring to Paschen's law.(4) We have studied the application of ZnO nanostructures for solar energy harvesting. First, as-grown and (CdSe) ZnS QDs decorated ZnO NBs and ZnONWs were tested for photocurrent generation. All these nanostructures offered fast response time to solar radiation. The decoration of QDs decreases the stable current level produced by ZnONWs but increases that generated by NBs. It is possible that NBs offer more stable surfaces for the attachment of QDs. In addition, our results suggests that performance degradation of solar cells made by growing ZnO NWs on ITO is due to the increase in resistance of ITO after the high temperature growth process. Hydrogen annealing also improve the efficiency of the solar cells by decreasing the resistance of ITO. Due to the issues on ITO, we use Ni foil as the growth substrates. Performance of solar cells made by growing ZnO NWs on Ni foils degraded after Hydrogen annealing at both low (300°C) and high (600°C) temperatures since annealing passivates native defects in ZnONWs and thus reduce the absorption of visible spectra from our solar simulator. Decoration of QDs improves the efficiency of such solar cells by increasing absorption of light in the visible region. Using a better electrolyte than phosphate buffer solution (PBS) such as KI also improves the solar cell efficiency. (5) Finally, we have attempted p-type doping of ZnO NWs using various growth precursors including phosphorus pentoxide, sodium fluoride, and zinc fluoride. We have also attempted to create p-type carriers via introducing interstitial fluorine by annealing ZnO nanostructures in diluted fluorine gas. In brief, we are unable to reproduce the growth of reported p-type ZnO nanostructures. However; we have identified the window of temperature and duration of post-growth annealing of ZnO NWs in dilute fluorine gas which leads to suppression of native defects. This is the first experimental effort on post-growth annealing of ZnO NWs in dilute fluorine gas although this has been suggested by a recent theory for creating p-type semiconductors. In our experiments the defect band peak due to native defects is found to decrease by annealing at 300°C for 10 -- 30 minutes. One of the major future works will be to determine the type of charge carriers in our annealed ZnONWs.

Types of work-related behavior and experiences and stress coping strategies among single mothers and mothers in relationships differentiating role of work satisfaction.

PubMed

Napora, Elżbieta; Andruszkiewicz, Anna; Basińska, Małgorzata Anna

2018-01-01

The purpose of the study has been to describe functioning of single and mothers in relationships (married or in informal relationships) at work and verify if the declared degree of work satisfaction differentiates types of behavior at work and stress coping strategies in both groups of mothers. The study was conducted on equal samples of single mothers (N = 186) and mothers from 2-parent families (N = 186) using Latack Coping Scale that measures work-related stress coping strategies, the AVEM (Arbeitsbezogenes Verhaltens- und Erlebensmuster - Work-Related Behavior and Experience Pattern) questionnaire, and a survey. It showed similarity between the studied groups in terms of the measured variables. There were considerable differences between single and married mothers in terms of support seeking strategies. The interaction of work satisfaction and the type of motherhood significantly differentiates (p = 0.03) the avoidance strategy of resignation. That strategy of resignation was more frequently used by single mothers with lower work satisfaction, who were distinctly different from those whose work satisfaction was higher, and from the mothers in relationships (married or in informal relationships) (regardless of the level of their work satisfaction). Int J Occup Med Environ Health 2018;31(1):55-69. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Room-temperature synthesized copper iodide thin film as degenerate p-type transparent conductor with a boosted figure of merit

PubMed Central

Kneiβ, Max; Lorenz, Michael

2016-01-01

A degenerate p-type conduction of cuprous iodide (CuI) thin films is achieved at the iodine-rich growth condition, allowing for the record high room-temperature conductivity of ∼156 S/cm for as-deposited CuI and ∼283 S/cm for I-doped CuI. At the same time, the films appear clear and exhibit a high transmission of 60–85% in the visible spectral range. The realization of such simultaneously high conductivity and transparency boosts the figure of merit of a p-type TC: its value jumps from ∼200 to ∼17,000 MΩ−1. Polycrystalline CuI thin films were deposited at room temperature by reactive sputtering. Their electrical and optical properties are examined relative to other p-type transparent conductors. The transport properties of CuI thin films were investigated by temperature-dependent conductivity measurements, which reveal a semiconductor–metal transition depending on the iodine/argon ratio in the sputtering gas. PMID:27807139

Beyond the usual suspects: target group- and behavior-specific factors add to a theory-based sun protection intervention for teenagers.

PubMed

Schüz, Natalie; Eid, Michael

2013-10-01

Sun protection standards among teenagers are low while sun exposure peaks in this age group. Study 1 explores predictors of adolescent protection intentions and exposure behavior. Study 2 tests the effectiveness of an intervention based on these predictors. Study 1(cross-sectional, N = 207, ages 15-18) and Study 2 (RCT, N = 253, ages 13-19) were conducted in schools. Path models were used to analyze data. Self-efficacy (β = .26, p < .001) and time perspective (β = .17, p = .014) were the strongest predictors of intentions; appearance motivation (β = .54, p < .001) and intention (β = -.18, p = .015) predicted behavior. The intervention effected changes in all predictors except self-efficacy. Changes in outcome expectancies (β = .19, p < .001) and time perspective (β = .09, p = .039) predicted changes in intention, while changes in intention (β = -.17, p = .002) and appearance motivation (β = .29, p < .001) predicted behavior changes. Target group- and behavior-specific intervention components are as important for changes in intentions and behavior as components derived from common health behavior theories.

A room temperature ethanol sensor made from p-type Sb-doped SnO2 nanowires.

PubMed

Wu, Jyh Ming

2010-06-11

A p-type ethanol sensor with a response time of approximately 8.3 s at room temperature was produced by SnO(2):Sb nanowires. The electrical properties of p-type SnO(2) nanowires are stable with a hole concentration of 1.544 x 10(17) cm(-3) and a field-effect mobility of 22 cm(2) V(-2) S(-1). X-ray photoelectron spectroscopy (XPS) and Hall measurement revealed that as-synthesized nanowires exhibit p-type behavior. A comprehensive investigation of the p-type sensing mechanism is reported.

Chemical manipulation of phase stability and electronic behavior in Cu 4−x Ag x Se 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olvera, A.; Bailey, T. P.; Uher, C.

Gradual stoichiometric chemical substitution of Cu by Ag in the p-type Cu 2 Se phase enables phase segregation and incremental switching of the electronic transport to n-type behavior for large Ag/Cu ratios.

Chemical manipulation of phase stability and electronic behavior in Cu 4−x Ag x Se 2

DOE PAGES

Olvera, A.; Bailey, T. P.; Uher, C.; ...

2018-01-01

Gradual stoichiometric chemical substitution of Cu by Ag in the p-type Cu 2 Se phase enables phase segregation and incremental switching of the electronic transport to n-type behavior for large Ag/Cu ratios.

Size effects in non-linear heat conduction with flux-limited behaviors

NASA Astrophysics Data System (ADS)

Li, Shu-Nan; Cao, Bing-Yang

2017-11-01

Size effects are discussed for several non-linear heat conduction models with flux-limited behaviors, including the phonon hydrodynamic, Lagrange multiplier, hierarchy moment, nonlinear phonon hydrodynamic, tempered diffusion, thermon gas and generalized nonlinear models. For the phonon hydrodynamic, Lagrange multiplier and tempered diffusion models, heat flux will not exist in problems with sufficiently small scale. The existence of heat flux needs the sizes of heat conduction larger than their corresponding critical sizes, which are determined by the physical properties and boundary temperatures. The critical sizes can be regarded as the theoretical limits of the applicable ranges for these non-linear heat conduction models with flux-limited behaviors. For sufficiently small scale heat conduction, the phonon hydrodynamic and Lagrange multiplier models can also predict the theoretical possibility of violating the second law and multiplicity. Comparisons are also made between these non-Fourier models and non-linear Fourier heat conduction in the type of fast diffusion, which can also predict flux-limited behaviors.

Lithium ameliorates open-field and elevated plus maze behaviors, and brain phospho-glycogen synthase kinase 3-beta expression in fragile X syndrome model mice.

PubMed

Chen, Xi; Sun, Weiwen; Pan, Ying; Yang, Quan; Cao, Kaiyi; Zhang, Jin; Zhang, Yizhi; Chen, Mincong; Chen, Feidi; Huang, Yueling; Dai, Lijun; Chen, Shengqiang

2013-10-01

To investigate whether lithium modifies open-field and elevated plus maze behavior, and brain phospho-glycogen synthase kinase 3 (P-GSK3beta) expression in Fmr1 knockout mice. One hundred and eighty FVB mice, including knockout and wild type, with an age of 30 days were used. An open-field and elevated plus maze was utilized to test behavior, while western blot was used to measure the P-GSK3beta expression. Six groups were formed: control (saline), lithium chloride 30, 60, 90, 120, and 200 mg/kg. The experiments were carried out in the Institute of Neuroscience, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China between January and June 2012. Lithium significantly decreased total distance, crossing, central area time, and center entry in the open-field test (p<0.05), and significantly reduced open-arm tracking, open-arm entry, and open-arm time in the elevated plus maze (p<0.05) in knockout mice. In wild type mice, significant changes were observed in both behavior tests in some treatment groups. Lithium ameliorated P-GSK3beta expression in the hippocampus of all the treatment groups in knockout mice (p<0.05). However, lithium did not modify either GSK3beta expression in tissues of knockout mice, or P-GSK3beta or GSK3beta expression in tissues of wild type mice. Lithium ameliorated open-field and elevated plus maze behaviors of Fmr1 knockout mice. This effect may be related to its enhancement of P-GSK3beta expression. Our findings suggest that lithium might have a therapeutic effect in fragile X syndrome.

Electronic structure and p-type doping of ZnSnN2

NASA Astrophysics Data System (ADS)

Wang, Tianshi; Janotti, Anderson; Ni, Chaoying

ZnSnN2 is a promising solar-cell absorber material composed of earth abundant elements. Little is known about doping, defects, and how the valence and conduction bands in this material align with the bands in other semiconductors. Using density functional theory with the the Heyd-Scuseria-Ernzerhof hybrid functional (HSE06), we investigate the electronic structure of ZnSnN2, its band alignment to other semiconductors, such as GaN and ZnO, the possibility of p-type doping, and the possible causes of the observed unintentional n-type conductivity. We find that the position of the valence-band maximum of ZnSnN2 is 0.55 eV higher than that of GaN, yet the conduction-band minimum is close to that in ZnO. As possible p-type dopants, we explore Li, Na, and K substituting on the Zn site. Finally, we discuss the cause of unintentional n-type conductivity by analyzing the position of the conduction-band minimum with respect to that of GaN and ZnO.

Behavioral Outcomes of Extremely Low Birth Weight Children at Age 8 Years

PubMed Central

Hack, Maureen; Taylor, Hudson G.; Schluchter, Mark; Andreias, Laura; Drotar, Dennis; Klein, Nancy

2011-01-01

Objective To describe the prevalence of behavioral problems and symptomatology suggestive of Autism and Asperger’s disorders at age 8 years among extremely low birth weight (ELBW, <1 kg) children, born 1992 through 1995. Method Parent reports of the behavior of 219 ELBW (mean birth weight, 810 g; gestational age 26 weeks) were compared with 176 normal birth weight children of similar maternal sociodemographic status, sex, and age. Behavior was assessed via the Child Symptom Inventory that includes both Symptom Severity Scores and scores meeting DSM-IV criteria for disorders. Results ELBW compared with normal birth weight children had significantly higher mean Symptom Severity Scores for the inattentive, hyperactive, and combined types of attention-deficit hyperactivity disorder (all p < .001) as well as higher scores for Generalized Anxiety (p < .01) and Autistic (p < .001) and Asperger’s (p < .01) disorders. When DSM-IV criteria were considered, ELBW children also had significantly higher rates of attention-deficit hyperactivity disorder of the inattentive (10% vs 3%, p < .01) and combined (5% vs 0.6%, p < .05) types. Conclusions Attention-deficit hyperactivity disorder, mainly the inattentive type is prevalent among ELBW children. Our findings of an increase in symptoms pertaining to Autistic and Asperger’s disorders at school age agree with recent reports of others during early childhood. Early identification and intervention for these problems might improve child functioning and ameliorate parent and child distress. PMID:19322106

Coexistence of the social types: genetic population structure in the ant Formica exsecta.

PubMed

Seppä, Perttu; Gyllenstrand, Niclas; Corander, Jukka; Pamilo, Pekka

2004-11-01

The ant Formica exsecta has two types of colonies that exist in sympatry but usually as separate subpopulations: colonies with simple social organization and single queens (M type) or colonial networks with multiple queens (P type). We used both nuclear (DNA microsatellites) and mitochondrial markers to study the transition between the social types, and the contribution of males and females in gene flow within and between the types. Our results showed that the social types had different spatial genetic structures. The M subpopulations formed a fairly uniform population, whereas the P subpopulations were, on average, more differentiated from each other than from the nearby M subpopulations and could have been locally established from the M-type colonies, followed by philopatric behavior and restricted emigration of females. Thus, the relationship between the two social types resembles that of source (M type) and sink (P type) populations. The comparison of mitochondrial (phiST) and nuclear (FST) differentiation indicates that the dispersal rate of males is four to five times larger than that of females both among the P-type subpopulations and between the social types. Our results suggest that evolution toward complex social organization can have an important effect on genetic population structure through changes in dispersal behavior associated with different sociogenetic organizations.

First-principles investigation of quantum transport in GeP3 nanoribbon-based tunneling junctions

NASA Astrophysics Data System (ADS)

Wang, Qiang; Li, Jian-Wei; Wang, Bin; Nie, Yi-Hang

2018-06-01

Two-dimensional (2D) GeP3 has recently been theoretically proposed as a new low-dimensional material [ Nano Lett. 17(3), 1833 (2017)]. In this manuscript, we propose a first-principles calculation to investigate the quantum transport properties of several GeP3 nanoribbon-based atomic tunneling junctions. Numerical results indicate that monolayer GeP3 nanoribbons show semiconducting behavior, whereas trilayer GeP3 nanoribbons express metallic behavior owing to the strong interaction between each of the layers. This behavior is in accordance with that proposed in two-dimensional GeP3 layers. The transmission coefficient T( E) of tunneling junctions is sensitive to the connecting formation between the central monolayer GeP3 nanoribbon and the trilayer GeP3 nanoribbon at both ends. The T( E) value of the bottom-connecting tunneling junction is considerably larger than those of the middle-connecting and top-connecting ones. With increases in gate voltage, the conductances increase for the bottom-connecting and middle-connecting tunneling junctions, but decrease for the top-connecting tunneling junctions. In addition, the conductance decreases exponentially with respect to the length of the central monolayer GeP3 nanoribbon for all the tunneling junctions. I-V curves show approximately linear behavior for the bottom-connecting and middle-connecting structures, but exhibit negative differential resistance for the top-connecting structures. The physics of each phenomenon is analyzed in detail.

Bandgap Engineering of NiO-CdO

NASA Astrophysics Data System (ADS)

Francis, Christopher

A discussion of the earliest point defect and ADM theory studies then justifies the dissertation's selection of CdO--it's strong electrical properties are suitable for bandgap engineering. Investigations of previous literature involving the Group II-oxides of ZnO, MgO, and CdO lead to two key conclusions. First, few studies exist in which CdO is a primary alloying material. Second, the properties of CdO are tunable with better complementary materials such as NiO, a transition metal (TM) oxide, instead of commonly used ZnO and MgO. Given their unique properties, there is an opportunity to investigate the structure, properties, and behavior of CdO system after alloying it with NiO. Hall effect, optical reflectance and transmittance and X-ray diffraction measurements are utilized first and the structural, electrical transport and optical properties of NixCd1-xO films sputtered in argon (Ar) with radio frequency (RF) magnetron are then reported. This initial study shows that NixCd1-xO alloys are rocksalt-structured and exhibit a monotonic shift of the (220) diffraction peak to higher 2theta angles with increasing Ni concentration. The electron mobility and electron concentration decrease with increasing Ni--becoming highly resistive for Ni content greater than 43.4% Ni. This decrease in n-type conductivity is consistent with the movement expected from a virtual crystal approximation (VCA) of the conduction band minimum (CBM) from below to above the Fermi stabilization energy (EFS). The optical absorption edge of the alloys is tunable from CdO to NiO. An intrinsic, carrier-free bandgap of the alloys, Eg, was calculated from the electrical and optical measurements, accounting for Burstein-Moss carrier filling and carrier-induced bandgap correlation effects. An unusual super linear composition dependence of the intrinsic bandgap is revealed when accounting for these effects. The super linear behavior was initially attributed to an interaction between the conduction-band extended states and localized donor and acceptor d-states of Ni. To probe the mechanisms behind the anomalous electrical transport and optical behaviors of the Ar sputtered alloys a collection of experimental and modeling investigations via ion irradiation, band anticrossing (BAC) simulations and X-Ray Photoelectron Spectroscopy-Ultraviolet Photoelectron Spectroscopy (XPS-UPS) was then used. This study discovered that the introduction of a TM with two impurity levels leads to interactions that reconstruct both the conduction and valence bands of the alloy with increasing Ni. Irradiation of the films leads to a saturation of the electron concentration associated with the pinning of the Fermi level at EFS. The composition dependence of the pinned EF enables determination of the CBM energy relative to the vacuum level. There is an unusually strong deviation of this CBM energy observed from the VCA which is then explained by a BAC interaction between localized 3d states of Ni and the extended states of the NixCd1-xO alloy host. The resulting band structure is responsible for the dependence on composition of the electrical and optical properties of the alloys, the rapid reduction of the electron mobility, and previously observed positive bandgap bowing parameter. XPS-UPS studies confirm that the Gamma- and L-point valence band maxima in the Cd-rich alloys are unaffected by interactions with Ni d-states. The results from this study provide much-needed context to the previously reported, but unexplained, electrical transport and optical behavior found in NixCd 1-xO, NixMg1-xO and Ni1-xZnxO alloys--the interactions govern their measured electrical and optical properties. These breakthroughs are also applicable to metal-oxide-based semiconducting alloys with TM acting as the dopant or alloying agents--such as V-doped ZnO. With an understanding of the structure, properties, and behavior of n-type, Ar sputtered NixCd1-xO, exploratory work for applications was then conducted. First, the electrochemical modification of these alloys for electrochromic windows was completed and the resulting electrical transport and optical properties were reported. Second, separate studies on the modification of NixCd 1-xO with the percent of O2 sputtering gas were implemented to evoke p-type conductivity for p-n junctions and hole emitter applications. Following this growth method, rapid thermal annealing studies under N 2 and O2-rich environments were conducted. These studies probed the defect mechanisms and discussed the optimal processing conditions that encourage the growth of reproducible and measurable p-type conductivity in NixCd1-xO. By altering the percent of O2 in the growth ambient, NixCd1-xO films with tunable electrical transport properties and charge type are realized--the first such result of its kind.

A systematic review on the effectiveness of cognitive behavioral therapy for posttraumatic stress disorder.

PubMed

Mendes, Deise D; Mello, Marcelo Feijó; Ventura, Paula; Passarela, Cristiane De Medeiros; Mari, Jair de Jesus

2008-01-01

Cognitive behavioral therapy (CBT) is the most common psychotherapy approach for the treatment of PTSD. Nevertheless, previous reviews on the efficacy of several types of psychotherapy were unable to detect differences between CBT and other psychotherapies. The purpose of this study was to conduct systematic review on the efficacy ofCBT in comparison with studies that used other psychotherapy techniques. Databases were searched using the following terms: posttraumatic stress disorder/stress disorder, treatment/psychotherapy/behavior cognitive therapy, randomized trials, and adults. Randomized clinical trials published between 1980 and 2005 and that compared CBT with other treatments for PTSD was included. The main outcomes were remission, clinical improvement, dropout rates and changes in symptoms. The 23 clinical trials included in the review comprised 1923 patients: 898 in the treatment group and 1,025 in the control group. CBT had better remission rates than EMDR (RR = 0.35; 95% CI: 0.16; 0.79; p = 0.01) or supportive therapies (RR = 0.43; 95% CI: 0.25; 0.74; p = 0.002, completer analysis). CBT was comparable to Exposure Therapy (ET) (RR = 0.90; 95% CI: 0.58; 1.40; p = 0.64), and cognitive therapy (CT) (RR = 1.01; 95% CI: 0.67; 1.51; p = 0.98) in terms of efficacy and compliance. These findings suggest that specific therapies, such as CBT, exposure therapy and cognitive therapy are equally effective, and more effective than supportive techniques in the treatment of PTSD.

Using the theory of planned behavior to predict infant restraint use in Saudi Arabia.

PubMed

Nelson, Anna; Modeste, Naomi N; Marshak, Helen H; Hopp, Joyce W

2014-09-01

To determine whether the theory of planned behavior (TPB) predicted intent of child restraint system (CRS) use among pregnant women in the Kingdom of Saudi Arabia (KSA). In this cross-sectional study conducted in Dallah Hospital, Riyadh, KSA during June-July 2013, 196 pregnant women completed surveys assessing their beliefs regarding CRS. Simultaneous observations were conducted among a different sample of 150 women to determine CRS usage at hospital discharge following maternity stay. Logistic regression model with TPB constructs and covariates as predictors of CRS usage intent was significant (χ2=64.986, p<0.0001) and predicted 38% of intent. There was an increase in odds of intent for attitudes (31.5%, p<0.05), subjective norm (55.3%, p<0.001), and perceived behavioral control (76.9%, p<0.001). The 3 logistic regression models testing the association of the relevant set of composite belief scores were also significant for attitudes (χ2=16.803, p<0.05), subjective norm (χ2=29.681, p<0.0001), and perceived behavioral control (χ2=20.516, p<0.05). The behavioral observation showed that none of the 150 women observed used CRS for their newborn at discharge. The TPB constructs were significantly and independently associated with higher intent for CRS usage. While TPB appears to be a useful tool to identify beliefs related to CRS usage intentions in KSA, the results of the separate behavioral observation indicate that intentions may not be related to the actual usage of CRS in the Kingdom. Further studies are recommended to examine this association.

Anxiety, depression and behavioral problems among adolescents with recurrent headache: the Young-HUNT study

PubMed Central

2014-01-01

Background It is well documented that both anxiety and depression are associated with headache, but there is limited knowledge regarding the relation between recurrent primary headaches and symptoms of anxiety and depression as well as behavioral problems among adolescents. Assessment of co-morbid disorders is important in order to improve the management of adolescents with recurrent headaches. Thus the main purpose of the present study was to assess the relationship of recurrent headache with anxiety and depressive symptoms and behavioral problems in a large population based cross-sectional survey among adolescents in Norway. Methods A cross-sectional, population-based study was conducted in Norway from 1995 to 1997 (Young-HUNT1). In Young-HUNT1, 4872 adolescents aged 12 to 17 years were interviewed about their headache complaints and completed a comprehensive questionnaire that included assessment of symptoms of anxiety and depression and behavioral problems, i.e. conduct and attention difficulties. Results In adjusted multivariate analyses among adolescents aged 12–14 years, recurrent headache was associated with symptoms of anxiety and depression (OR: 2.05, 95% CI: 1.61-2.61, p < 0.001), but not with behavioral problems. A significant association with anxiety and depressive symptoms was evident for all headache categories; i.e. migraine, tension-type headache and non-classifiable headache. Among adolescents aged 15–17 years there was a significant association between recurrent headache and symptoms of anxiety and depression (OR: 1.64, 95% CI: 1.39-1.93, p < 0,001) and attention difficulties (OR: 1.25, 95% CI: 1.09-1.44, p =0.001). For migraine there was a significant association with both anxiety and depressive symptoms and attention difficulties, while tension-type headache was significantly associated only with symptoms of anxiety and depression. Non-classifiable headache was associated with attention difficulties and conduct difficulties, but not with anxiety and depressive symptoms. Headache frequency was significantly associated with increasing symptoms scores for anxiety and depressive symptoms as well as attention difficulties, evident for both age groups. Conclusions The results from the present study indicate that both anxiety and depressive symptoms and behavioral problems are associated with recurrent headache, and should accordingly be considered a part of the clinical assessment of children and adolescents with headache. Identification of these associated factors and addressing them in interventions may improve headache management. PMID:24925252

Passion for Academics and Problematic Health Behaviors.

PubMed

Bureau, Alexander T; Razon, Selen; Saville, Bryan K; Tokac, Umit; Judge, Lawrence W

2017-01-01

According to the Dualistic Model of Passion (39), passion entails valuing, liking, and spending time on an activity. The Dualistic Model also posits two types of passion for activities: harmonious passion (individual voluntarily engages in the activity) and obsessive passion (individual is compelled to engage in the activity). The purpose of the present study was to examine the possible links between college students' passion for academic activities and problematic health behaviors including smoking, excessive drinking, exercise addiction, disordered eating, and sleepiness, which is a possible indicator of sleep deprivation. Participants (n = 502) completed a survey gauging passion type and health behaviors. Regression analyses revealed obsessive passion for academic activities was positively associated with scores on measures of excessive drinking (β = .15, p= .008), exercise addiction (β = .19, p<.001), and disordered eating (β = .17, p < .001) but was not associated with sleep deprivation (β = .07, p = .15). Harmonious passion for academic activities, in contrast, was negatively associated with excessive drinking behavior (β = -.16, p = .002) and sleep deprivation (β = -.13, p = .007) but was not associated with exercise addiction (β = .002, p = .97) and disordered eating (β = -.04, p = .37). These findings provide further support for the Dualistic Model of Passion. Students who are obsessively passionate about their academic activities are more likely to engage in poor health behaviors and, in turn, may experience greater negative outcomes than students who are harmoniously passionate about their academics.

Type I and Type II error concerns in fMRI research: re-balancing the scale

PubMed Central

Cunningham, William A.

2009-01-01

Statistical thresholding (i.e. P-values) in fMRI research has become increasingly conservative over the past decade in an attempt to diminish Type I errors (i.e. false alarms) to a level traditionally allowed in behavioral science research. In this article, we examine the unintended negative consequences of this single-minded devotion to Type I errors: increased Type II errors (i.e. missing true effects), a bias toward studying large rather than small effects, a bias toward observing sensory and motor processes rather than complex cognitive and affective processes and deficient meta-analyses. Power analyses indicate that the reductions in acceptable P-values over time are producing dramatic increases in the Type II error rate. Moreover, the push for a mapwide false discovery rate (FDR) of 0.05 is based on the assumption that this is the FDR in most behavioral research; however, this is an inaccurate assessment of the conventions in actual behavioral research. We report simulations demonstrating that combined intensity and cluster size thresholds such as P < 0.005 with a 10 voxel extent produce a desirable balance between Types I and II error rates. This joint threshold produces high but acceptable Type II error rates and produces a FDR that is comparable to the effective FDR in typical behavioral science articles (while a 20 voxel extent threshold produces an actual FDR of 0.05 with relatively common imaging parameters). We recommend a greater focus on replication and meta-analysis rather than emphasizing single studies as the unit of analysis for establishing scientific truth. From this perspective, Type I errors are self-erasing because they will not replicate, thus allowing for more lenient thresholding to avoid Type II errors. PMID:20035017

Associations between suicidal behavior and childhood abuse and neglect: A meta-analysis.

PubMed

Liu, Jianbo; Fang, Yumin; Gong, Jingbo; Cui, Xilong; Meng, Tiantian; Xiao, Bo; He, Yuqiong; Shen, Yanmei; Luo, Xuerong

2017-10-01

Relationships of some types of childhood maltreatment and suicidal behavior remain controversial and inconclusive. Medline, Embase, PsycINFO and Cochrane library were searched for eligible studies, and the results were synthesized in meta-analyses. childhood maltreatment was associated positively with suicidal behavior in the total population and maltreatment subgroups. Emotional abuse had the strongest effect (OR =2.33, SMD =0.660, P<0.001). Subgroup analyses showed that the effects of childhood abuse (OR =1.55, SMD =0.523) and neglect (OR =1.25, SMD =0.31) were significant. According to the analysis of dichotomous outcomes, childhood maltreatment was associated positively with suicidal behavior in men and women (women: OR =4.84, P<0.001; men: OR =1.03, P<0.001). Among populations, childhood maltreatment had the strongest effect on suicidal behavior in the general population (OR =3.78, P<0.001). However, the analysis of continuous outcomes showed that the effect was strongest in patients with chronic schizophrenia (SMD =0.89, P<0.001). In addition, childhood maltreatment was associated positively with suicide attempt (OR =1.11, SMD =0.48, P<0.001), but not with suicidal ideation. Some subgroup samples were not sufficiently large. Childhood maltreatment increases the risk of suicidal behavior. Emotional abuse had the strongest effect among the five types of maltreatment. The risk of suicidal behavior is higher in the general population, women, and individuals with chronic schizophrenia who have histories of childhood maltreatment. Copyright © 2017. Published by Elsevier B.V.

Comparisons of Conceptual Preference for Cultural and Leadership Behavior in an Information Technology Organization

ERIC Educational Resources Information Center

Valley, Amina B.

2009-01-01

The primary focus of the research study conducted was to analyze the predictive leadership behaviors of Southern Asian and United States individuals in the information technology career field. This research validates the leadership traits and behaviors of information technology types of United States individuals that enhance the impact of…

Effect of aging on ZnO and nitrogen doped P-Type ZnO

NASA Astrophysics Data System (ADS)

Majumdar, Sayanee; Bhunia, S.

2012-06-01

The withholding of p-type conductivity in as-prepared and 3% nitrogen (N) doped zinc oxide (ZnO) even after 2 months of preparation was systematically studied. The films were grown on glass substrates by pulsed laser deposition (PLD) at 350 °C under different conditions, viz. under vacuum and at oxygen (O) ambience using 2000 laser pulses. In O ambience for as-prepared ZnO the carrier concentration reduces and mobility increases with increasing number of laser shots. The resistivity of as-prepared and 3% N-doped ZnO is found to increase with reduction in hole concentration after 60 days of aging while maintaining its p-type conductivity irrespective of growth condition. AFM and electrical properties showed aging effect on the doped and undoped samples. For as-prepared ZnO, with time, O migration makes the film high resistive by reducing free electron concentrations. But for N-doped p-type ZnO, O-migration, metastable N and hydrogen atom present in the source induced instability in structure makes it less conducting p-type.

Synthesis, characterization and assembly of metal pnictide nanoparticles, and evaluation of their physicochemical (catalytic, magnetic, and semiconducting) properties

NASA Astrophysics Data System (ADS)

Senevirathne, Keerthisinghe

Synthesis of transition metal phosphide (Ni2P) and arsenide (MnAs) discrete nanoparticles was conducted by following a solution-phase arrested precipitation route and the size- and structure-dependent physicochemical properties of these materials were explored. Furthermore, the assembly of metal phosphide nanoparticles into a network structure via a sol-gel process and the evaluation of their structure related properties also was conducted. The surface ligation chemistry of unsupported Ni2P nanoparticles prepared by arrested precipitation was found to strongly impact the structural integrity and the hydrodesulfurization (HDS) catalytic activity of Ni 2P nanoparticles. The HDS activity of unsupported surface modified Ni2P nanoparticles is higher than that of unsupported Ni2P prepared by temperature programmed reduction (TPR) but considerably lower than silica-supported Ni2P prepared by TPR. However, by supporting the pre-formed Ni 2P nanoparticles on silica, activity comparable to that of silica-supported Ni2P prepared by TPR can be achieved. The synthetic control offered by the Ni2P nanoparticle preparation, not achieved by TPR methods, is expected to enable a systematic study of particle size and shape effects on HDS activity. By using arrested precipitation reactions, for the first time, discrete and dispersible MnAs nanoparticles have been prepared and their magnetic properties evaluated. Syntheses were developed to target both the thermodynamically stable alpha-type (hexagonal) and the metastable beta-type (orthorhombic) MnAs nanoparticles. Surprisingly, both types of ˜25 nm particles exhibit nearly identical ferromagnetic behavior with blocking temperatures, T B, in the region ˜275-310 K, TC's of 315 K and room temperature coercivities of HC ˜ 190-320 Oe. No evidence of the expected structural transition from alpha to beta-MnAs at TC is observed. Oxidative sol-gel assembly of nanoparticles to make nanoparticulate gels was successfully employed to Ni2P nanoparticles, and further extended to MnP and InP nanoparticles, for the first time. The gels were transformed into highly porous, high surface area (175-270 m2/g) 3-D structures (aerogels) via CO2 supercritical drying. Relative to discrete nanoparticles, Ni2P aerogels are less active to HDS, MnP aerogels have similar magnetic properties, and InP aerogels exhibit a greater degree of quantum confinement.

Semiconducting Organic-Inorganic Nanodots Heterojunctions: Platforms for General Photoelectrochemical Bioanalysis Application.

PubMed

Wang, Qian; Ruan, Yi-Fan; Zhao, Wei-Wei; Lin, Peng; Xu, Jing-Juan; Chen, Hong-Yuan

2018-03-20

In this study, semiconducting organic polymer dots (Pdots) and inorganic quantum dots (Qdots) were first utilized to construct the organic-inorganic nanodots heterojunction for the photoelectrochemical (PEC) bioanalysis application. Specifically, n-type CdS Qdots, p-type CdTe Qdots, and tetraphenylporphyrin (TPP)-doped poly[(9,9-dioctylfluorenyl-2,7-diyl)- co-(1,4-benzo-{2,1',3}-thiadazole)] (PFBT) Pdots were fabricated, and their energy levels, that is, their valence band (VB)/conduction band (CB) or lowest unoccupied molecular orbital (LUMO)/highest occupied molecular orbital (HOMO) values, were also determined. Then, these nanodots were integrated to construct four types of p-n and p-p organic-inorganic nanodots heterojunctions, that is, CdS Qdots/TPP-doped PFBT Pdots, TPP-doped PFBT Pdots/CdS Qdots, CdTe Qdots/TPP-doped PFBT Pdots, and TPP-doped PFBT Pdots/CdTe Qdots, on the transparent glass electrode. Upon light irradiation, four heterojunctions exhibited different PEC behaviors with some having prominent photocurrent enhancement. With the model molecule l-cysteine (l-cys) as target, the proposed PEC sensor exhibited good performances. In brief, this work presents the first semiconducting organic-inorganic nanodots heterojunction for PEC bioanalysis application, which could be easily used as a general platform for future PEC bioanalysis building. Besides, it is expected to inspire more interest in the design, development, and implementation of various organic-inorganic heterojunctions for advanced PEC bioanalysis in the future.

Interface energy band alignment at the all-transparent p-n heterojunction based on NiO and BaSnO3

NASA Astrophysics Data System (ADS)

Zhang, Jiaye; Han, Shaobo; Luo, Weihuang; Xiang, Shuhuai; Zou, Jianli; Oropeza, Freddy E.; Gu, Meng; Zhang, Kelvin H. L.

2018-04-01

Transparent oxide semiconductors hold great promise for many optoelectronic devices such as transparent electronics, UV-emitting devices, and photodetectors. A p-n heterojunction is the most ubiquitous building block to realize these devices. In this work, we report the fabrication and characterization of the interface properties of a transparent heterojunction consisting of p-type NiO and n-type perovskite BaSnO3. We show that high-quality NiO thin films can be epitaxially grown on BaSnO3 with sharp interfaces because of a small lattice mismatch (˜1.3%). The diode fabricated from this heterojunction exhibits rectifying behavior with a ratio of 500. X-ray photoelectron spectroscopy reveals a type II or "staggered" band alignment with valence and conduction band offsets of 1.44 eV and 1.86 eV, respectively. Moreover, a large upward band bending potential of 0.90 eV for BaSnO3 and a downward band bending potential of 0.15 eV for NiO were observed in the interface region. Such electronic properties have important implication for optoelectronic applications as the large built-in potential provides favorable energetics for photo-generated electron-hole separation/migration.

A Behavioral Lifestyle Intervention Enhanced With Multiple-Behavior Self-Monitoring Using Mobile and Connected Tools for Underserved Individuals With Type 2 Diabetes and Comorbid Overweight or Obesity: Pilot Comparative Effectiveness Trial.

PubMed

Wang, Jing; Cai, Chunyan; Padhye, Nikhil; Orlander, Philip; Zare, Mohammad

2018-04-10

Self-monitoring is a cornerstone of behavioral lifestyle interventions for obesity and type 2 diabetes mellitus. Mobile technology has the potential to improve adherence to self-monitoring and patient outcomes. However, no study has tested the use of a smartphone to facilitate self-monitoring in overweight or obese adults with type 2 diabetes mellitus living in the underserved community. The aim of this study was to examine the feasibility of and compare preliminary efficacy of a behavioral lifestyle intervention using smartphone- or paper-based self-monitoring of multiple behaviors on weight loss and glycemic control in a sample of overweight or obese adults with type 2 diabetes mellitus living in underserved communities. We conducted a randomized controlled trial to examine the feasibility and preliminary efficacy of a behavioral lifestyle intervention. Overweight or obese patients with type 2 diabetes mellitus were recruited from an underserved minority community health center in Houston, Texas. They were randomly assigned to one of the three groups: (1) behavior intervention with smartphone-based self-monitoring, (2) behavior intervention with paper diary-based self-monitoring, and (3) usual care group. Both the mobile and paper groups received a total of 11 face-to-face group sessions in a 6-month intervention. The mobile group received an Android-based smartphone with 2 apps loaded to help them record their diet, physical activity, weight, and blood glucose, along with a connected glucometer, whereas the paper group used paper diaries for these recordings. Primary outcomes of the study included percentage weight loss and glycated hemoglobin (HbA 1c ) changes over 6 months. A total of 26 patients were enrolled: 11 in the mobile group, 9 in the paper group, and 6 in the control group. We had 92% (24/26) retention rate at 6 months. The sample is predominantly African Americans with an average age of 56.4 years and body mass index of 38.1. Participants lost an average of 2.73% (mobile group) and 0.13% (paper group) weight at 6 months, whereas the control group had an average 0.49% weight gain. Their HbA 1c changed from 8% to 7 % in mobile group, 10% to 9% in paper group, and maintained at 9% for the control group. We found a significant difference on HbA 1c at 6 months among the 3 groups (P=.01). We did not find statistical group significance on percentage weight loss (P=.20) and HbA 1c changes (P=.44) overtime; however, we found a large effect size of 0.40 for weight loss and a medium effect size of 0.28 for glycemic control. Delivering a simplified behavioral lifestyle intervention using mobile health-based self-monitoring in an underserved community is feasible and acceptable and shows higher preliminary efficacy, as compared with paper-based self-monitoring. A full-scale randomized controlled trial is needed to confirm the findings in this pilot study. ClinicalTrials.gov NCT02858648; https://clinicaltrials.gov/ct2/show/NCT02858648 (Archived by WebCite at http://www.webcitation.org/6ySidjmT7). ©Jing Wang, Chunyan Cai, Nikhil Padhye, Philip Orlander, Mohammad Zare. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 10.04.2018.

A Behavioral Lifestyle Intervention Enhanced With Multiple-Behavior Self-Monitoring Using Mobile and Connected Tools for Underserved Individuals With Type 2 Diabetes and Comorbid Overweight or Obesity: Pilot Comparative Effectiveness Trial

PubMed Central

Cai, Chunyan; Padhye, Nikhil; Orlander, Philip; Zare, Mohammad

2018-01-01

Background Self-monitoring is a cornerstone of behavioral lifestyle interventions for obesity and type 2 diabetes mellitus. Mobile technology has the potential to improve adherence to self-monitoring and patient outcomes. However, no study has tested the use of a smartphone to facilitate self-monitoring in overweight or obese adults with type 2 diabetes mellitus living in the underserved community. Objective The aim of this study was to examine the feasibility of and compare preliminary efficacy of a behavioral lifestyle intervention using smartphone- or paper-based self-monitoring of multiple behaviors on weight loss and glycemic control in a sample of overweight or obese adults with type 2 diabetes mellitus living in underserved communities. Methods We conducted a randomized controlled trial to examine the feasibility and preliminary efficacy of a behavioral lifestyle intervention. Overweight or obese patients with type 2 diabetes mellitus were recruited from an underserved minority community health center in Houston, Texas. They were randomly assigned to one of the three groups: (1) behavior intervention with smartphone-based self-monitoring, (2) behavior intervention with paper diary-based self-monitoring, and (3) usual care group. Both the mobile and paper groups received a total of 11 face-to-face group sessions in a 6-month intervention. The mobile group received an Android-based smartphone with 2 apps loaded to help them record their diet, physical activity, weight, and blood glucose, along with a connected glucometer, whereas the paper group used paper diaries for these recordings. Primary outcomes of the study included percentage weight loss and glycated hemoglobin (HbA1c) changes over 6 months. Results A total of 26 patients were enrolled: 11 in the mobile group, 9 in the paper group, and 6 in the control group. We had 92% (24/26) retention rate at 6 months. The sample is predominantly African Americans with an average age of 56.4 years and body mass index of 38.1. Participants lost an average of 2.73% (mobile group) and 0.13% (paper group) weight at 6 months, whereas the control group had an average 0.49% weight gain. Their HbA1c changed from 8% to 7 % in mobile group, 10% to 9% in paper group, and maintained at 9% for the control group. We found a significant difference on HbA1c at 6 months among the 3 groups (P=.01). We did not find statistical group significance on percentage weight loss (P=.20) and HbA1c changes (P=.44) overtime; however, we found a large effect size of 0.40 for weight loss and a medium effect size of 0.28 for glycemic control. Conclusions Delivering a simplified behavioral lifestyle intervention using mobile health–based self-monitoring in an underserved community is feasible and acceptable and shows higher preliminary efficacy, as compared with paper-based self-monitoring. A full-scale randomized controlled trial is needed to confirm the findings in this pilot study. Trial Registration ClinicalTrials.gov NCT02858648; https://clinicaltrials.gov/ct2/show/NCT02858648 (Archived by WebCite at http://www.webcitation.org/6ySidjmT7) PMID:29636320

Predictors of Playing Augmented Reality Mobile Games While Walking Based on the Theory of Planned Behavior: Web-Based Survey.

PubMed

Koh, Hyeseung Elizabeth; Oh, Jeeyun; Mackert, Michael

2017-12-11

There has been a sharp increase in the number of pedestrians injured while using a mobile phone, but little research has been conducted to explain how and why people use mobile devices while walking. Therefore, we conducted a survey study to explicate the motivations of mobile phone use while walking. The purpose of this study was to identify the critical predictors of behavioral intention to play a popular mobile game, Pokemon Go, while walking, based on the theory of planned behavior (TPB). In addition to the three components of TPB, automaticity, immersion, and enjoyment were added to the model. This study is a theory-based investigation that explores the underlying mechanisms of mobile phone use while walking focusing on a mobile game behavior. Participants were recruited from a university (study 1; N=262) and Amazon Mechanical Turk (MTurk) (study 2; N=197) in the United States. Participants completed a Web-based questionnaire, which included measures of attitude, subjective norms, perceived behavioral control (PBC), automaticity, immersion, and enjoyment. Participants also answered questions regarding demographic items. Hierarchical regression analyses were conducted to examine hypotheses. The model we tested explained about 41% (study 1) and 63% (study 2) of people's intention to play Pokemon Go while walking. The following 3 TPB variables were significant predictors of intention to play Pokemon Go while walking in study 1 and study 2: attitude (P<.001), subjective norms (P<.001), and PBC (P=.007 in study 1; P<.001 in study 2). Automaticity tendency (P<.001), immersion (P=.02), and enjoyment (P=.04) were significant predictors in study 1, whereas enjoyment was the only significant predictor in study 2 (P=.01). Findings from this study demonstrated the utility of TPB in predicting a new behavioral domain-mobile use while walking. To sum up, younger users who are habitual, impulsive, and less immersed players are more likely to intend to play a mobile game while walking. ©Hyeseung Elizabeth Koh, Jeeyun Oh, Michael Mackert. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 11.12.2017.

Predictors of Playing Augmented Reality Mobile Games While Walking Based on the Theory of Planned Behavior: Web-Based Survey

PubMed Central

Oh, Jeeyun; Mackert, Michael

2017-01-01

Background There has been a sharp increase in the number of pedestrians injured while using a mobile phone, but little research has been conducted to explain how and why people use mobile devices while walking. Therefore, we conducted a survey study to explicate the motivations of mobile phone use while walking Objective The purpose of this study was to identify the critical predictors of behavioral intention to play a popular mobile game, Pokemon Go, while walking, based on the theory of planned behavior (TPB). In addition to the three components of TPB, automaticity, immersion, and enjoyment were added to the model. This study is a theory-based investigation that explores the underlying mechanisms of mobile phone use while walking focusing on a mobile game behavior. Methods Participants were recruited from a university (study 1; N=262) and Amazon Mechanical Turk (MTurk) (study 2; N=197) in the United States. Participants completed a Web-based questionnaire, which included measures of attitude, subjective norms, perceived behavioral control (PBC), automaticity, immersion, and enjoyment. Participants also answered questions regarding demographic items. Results Hierarchical regression analyses were conducted to examine hypotheses. The model we tested explained about 41% (study 1) and 63% (study 2) of people’s intention to play Pokemon Go while walking. The following 3 TPB variables were significant predictors of intention to play Pokemon Go while walking in study 1 and study 2: attitude (P<.001), subjective norms (P<.001), and PBC (P=.007 in study 1; P<.001 in study 2). Automaticity tendency (P<.001), immersion (P=.02), and enjoyment (P=.04) were significant predictors in study 1, whereas enjoyment was the only significant predictor in study 2 (P=.01). Conclusions Findings from this study demonstrated the utility of TPB in predicting a new behavioral domain—mobile use while walking. To sum up, younger users who are habitual, impulsive, and less immersed players are more likely to intend to play a mobile game while walking. PMID:29229586

Self-assembly behavior of poly(fluorenyl styrene)-block-poly(2-vinyl pyridine) and their blends with single wall carbon nanotubes (SWCNT)

NASA Astrophysics Data System (ADS)

Mezzenga, Raffaele; Li, Chaoxu; Hsu, Jung-Ching; Chen, Wen-Chang; Sugiyama, Kenji; Hirao, Akira

2010-03-01

We describe a supramolecular strategy to disperse carbon nanotubes in block copolymer matrices. To achieve the desired functions and morphologies, comb-type architectures in which one and two fluorene units attached on the styrene ring of polystyrene-block-poly(2-vinyl pyridine) were studied. Depending on the pendant fluorene units, the block ratio, the casting solvent and thermal annealing history, multiple morphologies were found. The phase diagram, compared to PS-b-P2VP, was interpreted in terms of the conformational asymmetry arising from grafting of fluorene units of variable lengths. Hydrogen bonds between COOH-SWCNT and P2VP favor miscibility of SWCNT within P2VP domains and the blending of these two components is reflected both on the final morphologies and on the electron conductivity of the blends.

High-Temperature Thermoelectric Properties of Perovskite-Type Pr0.9Sr0.1Mn1- x Fe x O3 (0 ≤ x ≤ 1)

NASA Astrophysics Data System (ADS)

Nakatsugawa, H.; Saito, M.; Okamoto, Y.

2017-05-01

Polycrystalline samples of Pr0.9Sr0.1Mn1- x Fe x O3 (0 ≤ x ≤ 1) have been synthesized using a conventional solid-state reaction method, and the crystal structure studied at room temperature. The magnetic susceptibility was measured from 5 K to 350 K. The electrical resistivity, Seebeck coefficient, and thermal conductivity were investigated as functions of temperature below 850 K. For all samples, the perovskite structure at room temperature exhibited orthorhombic Pbnm phase. While the Pr0.9Sr0.1MnO3 ( x = 0) sample exhibited ferromagnetic-like ground state below T C = 145 K (Curie temperature), the ferromagnetic transition temperature T C decreased with increasing x. The Seebeck coefficient of the samples with 0 ≤ x ≤ 0.8 decreased with increasing temperature because of double-exchange interaction of Mn ions. In fact, the carrier type for x = 0 changed from hole-like to electron-like behavior above 800 K. On the other hand, the samples with x ≥ 0.9 showed large positive Seebeck coefficient over the entire temperature range, indicating that the low-spin state of Fe ions dominated the electronic structure for this x range. In particular, the sample with x = 1 exhibited p-type thermoelectric properties with relatively high Seebeck coefficient, moderate electrical resistivity, and low thermal conductivity. Thus, the sample with x = 1 showed power factor of 20 μW m-1 K-2 at 850 K leading to ZT of 0.024 at this temperature, indicating that hole-doped perovskite-type iron oxide is a good candidate high-temperature thermoelectric p-type oxide.

Photo-assisted Kelvin probe force microscopy investigation of three dimensional GaN structures with various crystal facets, doping types, and wavelengths of illumination

NASA Astrophysics Data System (ADS)

Ali Deeb, Manal; Ledig, Johannes; Wei, Jiandong; Wang, Xue; Wehmann, Hergo-Heinrich; Waag, Andreas

2017-08-01

Three dimensional GaN structures with different crystal facets and doping types have been investigated employing the surface photo-voltage (SPV) method to monitor illumination-induced surface charge behavior using Kelvin probe force microscopy. Various photon energies near and below the GaN bandgap were used to modify the generation of electron-hole pairs and their motion under the influence of the electric field near the GaN surface. Fast and slow processes for Ga-polar c-planes on both Si-doped n-type as well as Mg-doped p-type GaN truncated pyramid micro-structures were found and their origin is discussed. The immediate positive (for n-type) and negative (for p-type) SPV response dominates at band-to-band and near-bandgap excitation, while only the slow process is present at sub-bandgap excitation. The SPV behavior for the semi-polar facets of the p-type GaN truncated pyramids has a similar characteristic to that on its c-plane, which indicates that it has a comparable band bending and no strong influence of the polarity-induced charges is detectable. The SPV behavior of the non-polar m-facets of the Si-doped n-type part of a transferred GaN column is similar to that of a clean c-plane GaN surface during illumination. However, the SPV is smaller in magnitude, which is attributed to intrinsic surface states of m-plane surfaces and their influence on the band bending. The SPV behavior of the non-polar m-facet of the slightly Mg-doped part of this GaN column is found to behave differently. Compared to c- and r-facets of p-type surfaces of GaN-light-emitting diode micro-structures, the m-plane is more chemically stable.

Deformation behavior of welded steel sandwich panels under quasi-static loading

DOT National Transportation Integrated Search

2011-03-16

This paper summarizes basic research (i.e., testing and analysis) : conducted to examine the deformation behavior of flat-welded : steel sandwich panels under two types of quasi-static loading: : (1) uniaxial compression; and (2) bending through an i...

Doping process of p-type GaN nanowires: A first principle study

NASA Astrophysics Data System (ADS)

Xia, Sihao; Liu, Lei; Diao, Yu; Feng, Shu

2017-10-01

The process of p-type doping for GaN nanowires is investigated using calculations starting from first principles. The influence of different doping elements, sites, types, and concentrations is discussed. Results suggest that Mg is an optimal dopant when compared to Be and Zn due to its stronger stability, whereas Be atoms are more inclined to exist in the interspace of a nanowire. Interstitially-doped GaN nanowires show notable n-type conductivity, and thus, Be is not a suitable dopant, which is to be expected since systems with inner substitutional dopants are more favorable than those with surface substitutions. Both interstitial and substitutional doping affect the atomic structure near dopants and induce charge transfer between the dopants and adjacent atoms. By altering doping sites and concentrations, nanowire atomic structures remain nearly constant. Substitutional doping models show p-type conductivity, and Mg-doped nanowires with doping concentrations of 4% showing the strongest p-type conductivity. All doping configurations are direct bandgap semiconductors. This study is expected to direct the preparation of high-quality GaN nanowires.

Trap-state-dominated suppression of electron conduction in carbon nanotube thin-film transistors.

PubMed

Qian, Qingkai; Li, Guanhong; Jin, Yuanhao; Liu, Junku; Zou, Yuan; Jiang, Kaili; Fan, Shoushan; Li, Qunqing

2014-09-23

The often observed p-type conduction of single carbon nanotube field-effect transistors is usually attributed to the Schottky barriers at the metal contacts induced by the work function differences or by the doping effect of the oxygen adsorption when carbon nanotubes are exposed to air, which cause the asymmetry between electron and hole injections. However, for carbon nanotube thin-film transistors, our contrast experiments between oxygen doping and electrostatic doping demonstrate that the doping-generated transport barriers do not introduce any observable suppression of electron conduction, which is further evidenced by the perfect linear behavior of transfer characteristics with the channel length scaling. On the basis of the above observation, we conclude that the environmental adsorbates work by more than simply shifting the Fermi level of the CNTs; more importantly, these adsorbates cause a poor gate modulation efficiency of electron conduction due to the relatively large trap state density near the conduction band edge of the carbon nanotubes, for which we further propose quantitatively that the adsorbed oxygen-water redox couple is responsible.

Cognitive function, behavioral problems, and physical function in long-term care insurance beneficiaries with dementia in South Korea: comparison of home care and institutional care services.

PubMed

Lee, Tae Wha; Yim, Eunsil; Cho, Eunhee; Chung, Jane

2014-08-01

To examine, in beneficiaries with long-term care (LTC) insurance (LTCI) with dementia in Korea, changes in cognitive function, behavioral symptoms, and physical function over time in relation to LTCI service type and to determine the 2-year effects of service type on those health outcomes. Secondary analyses of the existing LTCI data set from 2008 to 2010. South Korea. LTCI beneficiaries with dementia aged 65 and older (N=31,319). Participants were divided according to the service type that they were receiving home care (HC), institutional care (IC), and combined care (CC). A LTC approval checklist was used to determine the level of LTCI coverage of each participant and to assess cognitive function, behavioral symptoms, and physical function. Linear mixed models and multiple regression models were used. There were significant differences in cognitive function, behavioral symptoms, and physical function at baseline between individuals receiving the three service types (P<.001) and overall improvements in those outcomes over 2 years in the three groups (P<.001). After limiting the sample to those who had received LTCI services for the full 2 years (2008-2010) and adjusting for baseline characteristics, individuals receiving HC were more likely to have better cognitive and physical function than those receiving IC or CC but were likely to have more behavioral symptoms 2 years after the LTCI enrollment (P<.001). LTCI service type (HC, IC, CC) predicted cognitive function, behavioral symptoms, and physical function at 2-year follow-up in beneficiaries with dementia. Further research is necessary to examine the effect of LTC services on health outcomes in a longer observational cohort. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

Correlates and Determinants of Reproductive Behavior among Female University Students in Tehran

PubMed Central

Farahani, Farideh Khalaj Abadi; Cleland, John; Mehryar, Amir Hooshang

2012-01-01

Background This paper aims to examine the reproductive health and behaviors which might expose young people at risks of STIs/HIV and potential correlates of such behaviors among female college students in Tehran. Methods This paper focuses on the study conducted on a sample of 1743 female undergraduate students in four multidisciplinary universities in Tehran during 2005− 2006 using a two-stage stratified cluster sampling. The main focus was to determine the predictors of premarital heterosexual reproductive behavior among female students. Results The mean age of the unmarried students was 21.4 years. Low self-efficacy (OR=7.87, p <0.001), perceived peers’ liberal attitude on virginity (OR= 4.33), perception of parents’ liberal attitude towards relationship with the opposite sex and poor family atmosphere (OR=3.04 and 2.20, p <0.001, respectively) were predictors of ever having any type of sexual experience after controlling for other factors. The only predictors of penetrative sex remained in the logistic model were older age (OR=5.95), low self-efficacy (OR=10.86), poor family atmosphere (OR= 2.96), liberal parental attitude (OR=4.29) and liberal peer norms on virginity (OR= 4.90). Conclusion Interventional programs need to be designed at various levels such as enhancing self-efficacy, informing families of the protective role of a balanced control and monitoring over adolescents’ behavior and choices of peer network against premarital sexual activity. PMID:23926523

An application of the theory of planned behavior--a randomized controlled food safety pilot intervention for young adults.

PubMed

Milton, Alyssa C; Mullan, Barbara A

2012-03-01

Approximately 48 million Americans are affected by foodborne illness each year. Evidence suggests that the application of health psychology theory to food safety interventions can increase behaviors that reduce the incidence of illness such as adequately keeping hands, surfaces and equipment clean. This aim of this pilot study was to be the first to explore the effectiveness of a food safety intervention based on the Theory of Planned Behavior (TPB). Young adult participants (N = 45) were randomly allocated to intervention, general control or mere measurement control conditions. Food safety observations and TPB measures were taken at baseline and at 4-week follow-up. Within and between group differences on target variables were considered and regression analyses were conducted to determine the relationship between condition, behavior and the TPB intention constructs; attitude, subjective norm, perceived behavioral control (PBC). TPB variables at baseline predicted observed food safety behaviors. At follow-up, the intervention led to significant increases in PBC (p = .024) and observed behaviors (p = .001) compared to both control conditions. Furthermore, correlations were found between observed and self-reported behaviors (p = .008). The pilot intervention supports the utility of the TPB as a method of improving food safety behavior. Changes in TPB cognitions appear to be best translated to behavior via behavioral intentions and PBC. Further research should be conducted to increase effectiveness of translating TPB variables to food safety behaviors. The additional finding of a correlation between self-reported and observed behavior also has implications for future research as it provides evidence toward the construct validity of self-reported behavioral measures.

Effect of N2 flow during deposition on p-type ZnO film

NASA Astrophysics Data System (ADS)

Lin, Chiung-Wei; Liu, Bor-Chang

2017-01-01

In this study, the influence of a nitrogen source on p-type conductive ZnO films was studied. Rapid thermal oxidation was conducted to oxidize ZnN films and convert them to ZnO films. When an as-deposited ZnN film was prepared at a high nitrogen gas flow rate, the converted ZnO film possessed many acceptors and showed stable p-type conduction. This p-type conduction was attributed to the nitrogen gas flow providing many “No” states, which act as acceptors within the processed ZnO film. It was found that the as-deposited ZnN film prepared at a high nitrogen gas flow rate is oxidized slightly so that only a few nitrogen atoms were replaced by oxygen. The carrier concentration and mobility of the optimized oxidized ZnN film were 9.76 × 1017 cm-3 and 62.78 cm2 V-1 s-1, respectively. A good rectified current-voltage characteristic with a turn-on voltage of 3.65 V was achieved for the optimized ZnO:N/ZnO junction.

Gd3+ spin-lattice relaxation via multi-band conduction electrons in Y(1-x)Gd(x)In3: an electron spin resonance study.

PubMed

Cabrera-Baez, M; Iwamoto, W; Magnavita, E T; Osorio-Guillén, J M; Ribeiro, R A; Avila, M A; Rettori, C

2014-04-30

Interest in the electronic structure of the intermetallic compound YIn3 has been renewed with the recent discovery of superconductivity at T ∼ 1 K, which may be filamentary in nature. In this work we perform electron spin resonance (ESR) experiments on Gd(3+) doped YIn3 (Y1-xGdxIn3; 0.001 ⪅ x ⩽̸ 0.08), showing that the spin-lattice relaxation of the Gd(3+) ions, due to the exchange interaction between the Gd(3+) localized magnetic moment and the conduction electrons (ce), is processed via the presence of s-, p- and d-type ce at the YIn3 Fermi level. These findings are revealed by the Gd(3+) concentration dependence of the Korringa-like relaxation rate d(ΔH)/dT and g-shift (Δg = g - 1.993), that display bottleneck relaxation behavior for the s-electrons and unbottleneck behavior for the p- and d-electrons. The Korringa-like relaxation rates vary from 22(2) Oe/K for x ⪅ 0.001 to 8(2) Oe/K for x = 0.08 and the g-shift values change, respectively, from a positive Δg = +0.047(10) to a negative Δg = -0.008(4). Analysis in terms of a three-band ce model allows the extraction of the corresponding exchange interaction parameters Jfs, Jfp and Jfd.

Development and Psychometric Evaluation of a Health Action Process Approach Inventory for Healthful Diet Among Type 2 Diabetes Patients.

PubMed

Rohani, Hosein; Eslami, Ahmad Ali; Ghaderi, Arsalan; Bidkhori, Mohammad; Raei, Mehdi

2016-01-01

Long-term effects of diabetes could be prevented or delayed by adopting a proper diet. The aim of this study was to adapt and provide a pilot test using health action process approach (HAPA)-based inventory to capable of capturing significant determinants of healthful diet for diabetics. The inventory was reviewed by eight diabetes patients and verbal feedbacks with regard the comprehension, item relevance, and potential new content were obtained. Then, the inventory items were evaluated by an expert panel. Next exploratory factor analysis (EFA) was conducted to assess the scale constructs. Criterion validity was measured by Pearson correlation. Finally, reliability measures of internal consistency and test-retest analysis were determined. A total of 121 diabetic patients participated in this study. EFA extracted seven factors (risk-perception, action self-efficacy, outcome expectancies, maintenance self-efficacy, action and coping planning, behavioral intention, and recovery self-efficacy) explaining 81.14% of the total variance. There were significant correlations between behavioral intentions and both outcome expectancies (r = 0.55, P < 0.05) and action self-efficacy (r = 0.31, P < 0.004) and small to moderate correlations (rs = 23-40) between behavior and the volitional constructs of the HAPA model. Cronbach's alpha ranging from 0.65 to 0.95 and intraclass correlation coefficients ranging from 0.71 to 0.92 indicated an acceptable internal consistency. Developed scales were valid and reliable for measuring HAPA variables to be used with type 2 diabetes mellitus patients. Further examination with minority persons is warranted.

On the feasibility of p-type Ga2O3

NASA Astrophysics Data System (ADS)

Kyrtsos, Alexandros; Matsubara, Masahiko; Bellotti, Enrico

2018-01-01

We investigate the various cation substitutional dopants in Ga2O3 for the possibility of p-type conductivity using density functional theory. Our calculations include both standard density functional theory and hybrid functional calculations. We demonstrate that all the investigated dopants result in deep acceptor levels, not able to contribute to the p-type conductivity of Ga2O3. In light of these results, we compare our findings with other wide bandgap oxides and reexamine previous experiments on zinc doping in Ga2O3.

Do Different Facets of Impulsivity Predict Different Types of Aggression?

PubMed Central

Derefinko, Karen; DeWall, C. Nathan; Metze, Amanda V.; Walsh, Erin C.; Lynam, Donald R.

2011-01-01

The current study examined the relations between impulsivity-related traits (as assessed by the UPPS-P Impulsive Behavior Scale) and aggressive behaviors. Results indicated that UPPS-P Lack of Premeditation and Sensation Seeking were important in predicting general violence. In contrast, UPPS-P Urgency was most useful in predicting intimate partner violence. To further explore relations between intimate partner violence and Urgency, a measure of autonomic response to pleasant and aversive stimuli and facets of Neuroticism from the NEO PI-R were used as control variables. Autonomic responsivity was correlated with intimate partner violence at the zero-order level, and predicted significant variance in intimate partner violence in regression equations. However, UPPS-P Urgency was able to account for unique variance in intimate partner violence above and beyond measures of Neuroticism and arousal. Implications regarding the use of a multifaceted conceptualization of impulsivity in the prediction of different types of violent behavior are discussed. PMID:21259270

Psilocybin occasioned mystical-type experiences: immediate and persisting dose-related effects.

PubMed

Griffiths, Roland R; Johnson, Matthew W; Richards, William A; Richards, Brian D; McCann, Una; Jesse, Robert

2011-12-01

This dose-effect study extends previous observations showing that psilocybin can occasion mystical-type experiences having persisting positive effects on attitudes, mood, and behavior. This double-blind study evaluated psilocybin (0, 5, 10, 20, 30 mg/70 kg, p.o.) administered under supportive conditions. Participants were 18 adults (17 hallucinogen-naïve). Five 8-h sessions were conducted individually for each participant at 1-month intervals. Participants were randomized to receive the four active doses in either ascending or descending order (nine participants each). Placebo was scheduled quasi-randomly. During sessions, volunteers used eyeshades and were instructed to direct their attention inward. Volunteers completed questionnaires assessing effects immediately after and 1 month after each session, and at 14 months follow-up. Psilocybin produced acute perceptual and subjective effects including, at 20 and/or 30 mg/70 kg, extreme anxiety/fear (39% of volunteers) and/or mystical-type experience (72% of volunteers). One month after sessions at the two highest doses, volunteers rated the psilocybin experience as having substantial personal and spiritual significance, and attributed to the experience sustained positive changes in attitudes, mood, and behavior, with the ascending dose sequence showing greater positive effects. At 14 months, ratings were undiminished and were consistent with changes rated by community observers. Both the acute and persisting effects of psilocybin were generally a monotonically increasing function of dose, with the lowest dose showing significant effects. Under supportive conditions, 20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences having persisting positive effects on attitudes, mood, and behavior. Implications for therapeutic trials are discussed.

Unipolar n-Type Black Phosphorus Transistors with Low Work Function Contacts.

PubMed

Wang, Ching-Hua; Incorvia, Jean Anne C; McClellan, Connor J; Yu, Andrew C; Mleczko, Michal J; Pop, Eric; Wong, H-S Philip

2018-05-09

Black phosphorus (BP) is a promising two-dimensional (2D) material for nanoscale transistors, due to its expected higher mobility than other 2D semiconductors. While most studies have reported ambipolar BP with a stronger p-type transport, it is important to fabricate both unipolar p- and n-type transistors for low-power digital circuits. Here, we report unipolar n-type BP transistors with low work function Sc and Er contacts, demonstrating a record high n-type current of 200 μA/μm in 6.5 nm thick BP. Intriguingly, the electrical transport of the as-fabricated, capped devices changes from ambipolar to n-type unipolar behavior after a month at room temperature. Transmission electron microscopy analysis of the contact cross-section reveals an intermixing layer consisting of partly oxidized metal at the interface. This intermixing layer results in a low n-type Schottky barrier between Sc and BP, leading to the unipolar behavior of the BP transistor. This unipolar transport with a suppressed p-type current is favorable for digital logic circuits to ensure a lower off-power consumption.

Improved multi-level capability in Si3N4-based resistive switching memory using continuous gradual reset switching

NASA Astrophysics Data System (ADS)

Kim, Sungjun; Park, Byung-Gook

2017-01-01

In this letter, we compare three different types of reset switching behavior in a bipolar resistive random-access memory (RRAM) system that is housed in a Ni/Si3N4/Si structure. The abrupt, step-like gradual and continuous gradual reset transitions are largely determined by the low-resistance state (LRS). For abrupt reset switching, the large conducting path shows ohmic behavior or has a weak nonlinear current-voltage (I-V) characteristics in the LRS. For gradual switching, including both the step-like and continuous reset types, trap-assisted direct tunneling is dominant in the low-voltage regime, while trap-assisted Fowler-Nordheim tunneling is dominant in the high-voltage regime, thus causing nonlinear I-V characteristics. More importantly, we evaluate the multi-level capabilities of the two different gradual switching types, including both step-like and continuous reset behavior, using identical and incremental voltage conditions. Finer control of the conductance level with good uniformity is achieved in continuous gradual reset switching when compared to that in step-like gradual reset switching. For continuous reset switching, a single conducting path, which initially has a tunneling gap, gradually responds to pulses with even and identical amplitudes, while for step-like reset switching, the multiple conducting paths only respond to incremental pulses to obtain effective multi-level states.

Appetite Regulatory Hormones in Women With Anorexia Nervosa: Binge-Eating/Purging Versus Restricting Type

PubMed Central

Eddy, Kamryn T.; Lawson, Elizabeth A.; Meade, Christina; Meenaghan, Erinne; Horton, Sarah E.; Misra, Madhusmita; Klibanski, Anne; Miller, Karen K.

2015-01-01

Objective Anorexia nervosa is a psychiatric illness characterized by low weight, disordered eating, and hallmark neuroendocrine dysfunction. Behavioral phenotypes are defined by predominant restriction or bingeing/purging; binge-eating/purging type anorexia nervosa is associated with poorer outcome. The pathophysiology underlying anorexia nervosa types is unknown, but altered hormones, known to be involved in eating behaviors, may play a role. Method To examine the role of anorexigenic hormones in anorexia nervosa subtypes, we examined serum levels of peptide YY (PYY; total and active [3-36] forms), brain-derived neurotrophic factor (BDNF), and leptin as primary outcomes in women with OSM-5 restricting type anorexia nervosa (n=50), binge-eating/purging type anorexia nervosa (n = 22), and healthy controls (n = 22).1n addition, women completed validated secondary outcome measures of eating disorder psychopathology (Eating Disorder Examination-Questionnaire) and depression and anxiety symptoms (Hamilton Rating Scales for Depression [HDRS] and Anxiety [HARS]). The study samples were collected from May 22, 2004, to February 7, 2012. Results Mean PYY 3-36 and leptin levels were lower and BDNF levels higher in binge-eating/purging type anorexia nervosa than in restricting type anorexia nervosa (all Pvalues <.05). After controlling for body mass index, differences in PYY and PYY 3-36 between anorexia nervosa types were significant (P<.05) and differences in BDNF were at the trend level (P < .10). PYY 3-36 was positively (r=0.27, P=.02) and leptin was negatively (r=−0.51, P< .0001) associated with dietary restraint; BDNF was positively associated with frequency of purging (r=0.21, P=.04); and leptin was negatively associated with frequency of bingeing (r=−0.29, P=.007) and purging (r=−0.31, P=.004). Conclusions Among women with anorexia nervosa, the anorexigenic hormones PYY, BDNF, and leptin are differentially regulated between the restricting and binge/purge types. Whether these hormone pathways play etiologic roles with regard to anorexia nervosa behavioral types or are compensatory merits further study. PMID:25098834

Value-Eroding Teacher Behaviors Scale: A Validity and Reliability Study

ERIC Educational Resources Information Center

Arseven, Zeynep; Kiliç, Abdurrahman; Sahin, Seyma

2016-01-01

In the present study, it is aimed to develop a valid and reliable scale for determining value-eroding behaviors of teachers, hence their values of judgment. The items of the "Value-eroding Teacher Behaviors Scale" were designed in the form of 5-point likert type rating scale. The exploratory factor analysis (EFA) was conducted to…

Perceived family perceptions of breastfeeding and Chinese new mothers' breastfeeding behaviors.

PubMed

Lu, Hong; Li, Hongyan; Ma, Shuqin; Xia, Lijuan; Christensson, Kyllike

2011-11-01

To provide an understanding of Chinese new mothers' breastfeeding behaviors and especially to explore the relationship between the mothers perceived family perception about breastfeeding and the new mothers' breastfeeding behaviors. A cross-sectional questionnaire survey was conducted in Beijing and Yinchuan, the capital of Ning Xia Province, China. 214 new mothers with a baby at the age of 4 months were recruited to the study. The family perception of breastfeeding scale and the new mothers' breastfeeding behavior record were used. The response rate was n=200, 94%. Most of the new mothers perceived positive family perceptions about breastfeeding with an average score of 23.13 using the family perception of breastfeeding scale. Nearly half of the respondents reported that they exclusively breastfed their infants (n=94, 47%). The main reason for breastfeeding difficulty was inadequate lactation (n=56, 69%). The new mothers who breastfed their infants mentioned significantly stronger family perceptions/support compared to those who used mixed feeding or artificial feeding (p<0.001). There were no significant differences (p>0.05) in the types of mothers' feeding behaviors across the different age group, occupation, ethnicity, educational level, mode of delivery, the time of the baby's first suck, bottle feeding before the baby's first suck and the time of having colostrums. It is suggested to develop some strategies, such as family-centered antenatal and postnatal education programmes, to increase the rate of exclusive breastfeeding by influencing new mothers' families about breastfeeding. Further research is needed to explore socio-demographic variables associated with new-mothers' breastfeeding behaviors. Copyright © 2011 Elsevier B.V. All rights reserved.

High Temperature Integrated Thermoelectric Ststem and Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mike S. H. Chu

2011-06-06

The final goal of this project is to produce, by the end of Phase II, an all ceramic high temperature thermoelectric module. Such a module design integrates oxide ceramic n-type, oxide ceramic p-type materials as thermoelectric legs and oxide ceramic conductive material as metalizing connection between n-type and p-type legs. The benefits of this all ceramic module are that it can function at higher temperatures (> 700 C), it is mechanically and functionally more reliable and it can be scaled up to production at lower cost. With this all ceramic module, millions of dollars in savings or in new opportunitiesmore » recovering waste heat from high temperature processes could be made available. A very attractive application will be to convert exhaust heat from a vehicle to reusable electric energy by a thermoelectric generator (TEG). Phase I activities were focused on evaluating potential n-type and p-type oxide compositions as the thermoelectric legs. More than 40 oxide ceramic powder compositions were made and studied in the laboratory. The compositions were divided into 6 groups representing different material systems. Basic ceramic properties and thermoelectric properties of discs sintered from these powders were measured. Powders with different particles sizes were made to evaluate the effects of particle size reduction on thermoelectric properties. Several powders were submitted to a leading thermoelectric company for complete thermoelectric evaluation. Initial evaluation showed that when samples were sintered by conventional method, they had reasonable values of Seebeck coefficient but very low values of electrical conductivity. Therefore, their power factors (PF) and figure of merits (ZT) were too low to be useful for high temperature thermoelectric applications. An unconventional sintering method, Spark Plasma Sintering (SPS) was determined to produce better thermoelectric properties. Particle size reduction of powders also was found to have some positive benefits. Two composition systems, specifically 1.0 SrO - 0.8 x 1.03 TiO2 - 0.2 x 1.03 NbO2.5 and 0.97 TiO2 - 0.03 NbO2.5, have been identified as good base line compositions for n-type thermoelectric compositions in future module design. Tests of these materials at an outside company were promising using that company's processing and material expertise. There was no unique p-type thermoelectric compositions identified in phase I work other than several current cobaltite materials. Ca3Co4O9 will be the primary p-type material for the future module design until alternative materials are developed. BaTiO3 and rare earth titanate based dielectric compositions show both p-type and n-type behavior even though their electrical conductivities were very low. Further research and development of these materials for thermoelectric applications is planned in the future. A preliminary modeling and optimization of a thermoelectric generator (TEG) that uses the n-type 1.0 SrO - 1.03 x 0.8 TiO2 - 1.03 x 0.2 NbO2.5 was performed. Future work will combine development of ceramic powders and manufacturing expertise at TAM, development of SPS at TAM or a partner organization, and thermoelectric material/module testing, modeling, optimization, production at several partner organizations.« less

Novel transparent conductor with enhanced conductivity: hybrid of silver nanowires and dual-doped graphene

NASA Astrophysics Data System (ADS)

Sohn, Hiesang; Woo, Yun Sung; Shin, Weonho; Yun, Dong-Jin; Lee, Taek; Kim, Felix Sunjoo; Hwang, Jinyoung

2017-10-01

We present hybrid transparent conducting films based on silver nanowires (Ag NWs) and doped graphene through novel dual co-doping method by applying various dopants (HNO3 or Au for p-doping and N2H4 for n-doping) on top and bottom sides of graphene. We systematically investigated the effect of dual-doping on their surface as well as electrical and optical properties of graphene and Ag NW/graphene hybrid films through the combination study with various dopant types (p/p, p/n, n/p, and n/n). We found that the p/p-type dual-doped (p-type dopant: HNO3) graphene and its hybrid formation with Ag NWs appeared to be the most effective in enhancing the electrical properties of conductor (doped graphene with ΔR/R0 = 84% and Ag NW/doped graphene hybrid with ΔR/R0 = 62%), demonstrating doped monolayer graphene with high optical transmittance (TT = 97.4%), and sheet resistance (Rs = 188 Ω/sq.). We also note that dual-doping improved such electrical properties without any significant debilitation of optical transparency of conductors (doped graphene with ΔTT = 0.1% and Ag NW/doped graphene hybrid with ΔTT = 0.4%). In addition, the enhanced conductivity of p-type dual-doped graphene allows a hybrid system to form co-percolating network in which Ag NWs can form a secondary conductive path at grain boundaries of polycrystalline graphene.

Solution Synthesis of Iodine-Doped Red Phosphorus Nanoparticles for Lithium-Ion Battery Anodes.

PubMed

Chang, Wei-Chung; Tseng, Kuan-Wei; Tuan, Hsing-Yu

2017-02-08

Red phosphorus (RP) is a promising anode material for lithium-ion batteries due to its earth abundance and a high theoretical capacity of 2596 mA h g -1 . Although RP-based anodes for lithium-ion batteries have been reported, they were all in the form of carbon-P composites, including P-graphene, P-graphite, P-carbon nanotubes (CNTs), and P-carbon black, to improve P's extremely low conductivity and large volume change during cycling process. Here, we report the large-scale synthesis of red phosphorus nanoparticles (RPNPs) with sizes ranging from 100 to 200 nm by reacting PI 3 with ethylene glycol in the presence of cetyltrimethylammonium bromide (CTAB) in ambient environment. Unlike the insulator behavior of commercial RP (conductivity of <10 -12 S m -1 ), the conductivity of RPNPs is between 2.62 × 10 -3 and 1.81 × 10 -2 S m -1 , which is close to that of semiconductor germanium (1.02 × 10 -2 S m -1 ), and 2 orders of magnitude higher than silicon (5.35 × 10 -4 S m -1 ). Around 3-5 wt % of iodine-doping was found in RPNPs, which was speculated as the key to significantly improve the conductivity of RPNPs. The significantly improved conductivity of RPNPs and their uniform colloidal nanostructures enable them to be used solely as active materials for LIBs anodes. The RPNPs electrodes exhibit a high specific capacity of 1700 mA h g -1 (0.2 C after 100 cycles, 1 C = 2000 mA g -1 ), long cycling life (∼900 mA h g -1 after 500 cycles at 1 C), and outstanding rate capability (175 mA h g -1 at the charge current density of 120 A g -1 , 60 C). Moreover, as a proof-of-concept example, pouch-type full cells using RPNPs anodes and Li(Ni 0.5 Co 0.3 Mn 0.2 )O 2 (NCM-532) cathodes were assembled to show their practical uses.

Personal, Social, and Game-Related Correlates of Active and Non-Active Gaming Among Dutch Gaming Adolescents: Survey-Based Multivariable, Multilevel Logistic Regression Analyses

PubMed Central

de Vet, Emely; Chinapaw, Mai JM; de Boer, Michiel; Seidell, Jacob C; Brug, Johannes

2014-01-01

Background Playing video games contributes substantially to sedentary behavior in youth. A new generation of video games—active games—seems to be a promising alternative to sedentary games to promote physical activity and reduce sedentary behavior. At this time, little is known about correlates of active and non-active gaming among adolescents. Objective The objective of this study was to examine potential personal, social, and game-related correlates of both active and non-active gaming in adolescents. Methods A survey assessing game behavior and potential personal, social, and game-related correlates was conducted among adolescents (12-16 years, N=353) recruited via schools. Multivariable, multilevel logistic regression analyses, adjusted for demographics (age, sex and educational level of adolescents), were conducted to examine personal, social, and game-related correlates of active gaming ≥1 hour per week (h/wk) and non-active gaming >7 h/wk. Results Active gaming ≥1 h/wk was significantly associated with a more positive attitude toward active gaming (OR 5.3, CI 2.4-11.8; P<.001), a less positive attitude toward non-active games (OR 0.30, CI 0.1-0.6; P=.002), a higher score on habit strength regarding gaming (OR 1.9, CI 1.2-3.2; P=.008) and having brothers/sisters (OR 6.7, CI 2.6-17.1; P<.001) and friends (OR 3.4, CI 1.4-8.4; P=.009) who spend more time on active gaming and a little bit lower score on game engagement (OR 0.95, CI 0.91-0.997; P=.04). Non-active gaming >7 h/wk was significantly associated with a more positive attitude toward non-active gaming (OR 2.6, CI 1.1-6.3; P=.035), a stronger habit regarding gaming (OR 3.0, CI 1.7-5.3; P<.001), having friends who spend more time on non-active gaming (OR 3.3, CI 1.46-7.53; P=.004), and a more positive image of a non-active gamer (OR 2, CI 1.07–3.75; P=.03). Conclusions Various factors were significantly associated with active gaming ≥1 h/wk and non-active gaming >7 h/wk. Active gaming is most strongly (negatively) associated with attitude with respect to non-active games, followed by observed active game behavior of brothers and sisters and attitude with respect to active gaming (positive associations). On the other hand, non-active gaming is most strongly associated with observed non-active game behavior of friends, habit strength regarding gaming and attitude toward non-active gaming (positive associations). Habit strength was a correlate of both active and non-active gaming, indicating that both types of gaming are habitual behaviors. Although these results should be interpreted with caution because of the limitations of the study, they do provide preliminary insights into potential correlates of active and non-active gaming that can be used for further research as well as preliminary direction for the development of effective intervention strategies for replacing non-active gaming by active gaming among adolescents. PMID:25654657

Personal, social, and game-related correlates of active and non-active gaming among dutch gaming adolescents: survey-based multivariable, multilevel logistic regression analyses.

PubMed

Simons, Monique; de Vet, Emely; Chinapaw, Mai Jm; de Boer, Michiel; Seidell, Jacob C; Brug, Johannes

2014-04-04

Playing video games contributes substantially to sedentary behavior in youth. A new generation of video games-active games-seems to be a promising alternative to sedentary games to promote physical activity and reduce sedentary behavior. At this time, little is known about correlates of active and non-active gaming among adolescents. The objective of this study was to examine potential personal, social, and game-related correlates of both active and non-active gaming in adolescents. A survey assessing game behavior and potential personal, social, and game-related correlates was conducted among adolescents (12-16 years, N=353) recruited via schools. Multivariable, multilevel logistic regression analyses, adjusted for demographics (age, sex and educational level of adolescents), were conducted to examine personal, social, and game-related correlates of active gaming ≥1 hour per week (h/wk) and non-active gaming >7 h/wk. Active gaming ≥1 h/wk was significantly associated with a more positive attitude toward active gaming (OR 5.3, CI 2.4-11.8; P<.001), a less positive attitude toward non-active games (OR 0.30, CI 0.1-0.6; P=.002), a higher score on habit strength regarding gaming (OR 1.9, CI 1.2-3.2; P=.008) and having brothers/sisters (OR 6.7, CI 2.6-17.1; P<.001) and friends (OR 3.4, CI 1.4-8.4; P=.009) who spend more time on active gaming and a little bit lower score on game engagement (OR 0.95, CI 0.91-0.997; P=.04). Non-active gaming >7 h/wk was significantly associated with a more positive attitude toward non-active gaming (OR 2.6, CI 1.1-6.3; P=.035), a stronger habit regarding gaming (OR 3.0, CI 1.7-5.3; P<.001), having friends who spend more time on non-active gaming (OR 3.3, CI 1.46-7.53; P=.004), and a more positive image of a non-active gamer (OR 2, CI 1.07-3.75; P=.03). Various factors were significantly associated with active gaming ≥1 h/wk and non-active gaming >7 h/wk. Active gaming is most strongly (negatively) associated with attitude with respect to non-active games, followed by observed active game behavior of brothers and sisters and attitude with respect to active gaming (positive associations). On the other hand, non-active gaming is most strongly associated with observed non-active game behavior of friends, habit strength regarding gaming and attitude toward non-active gaming (positive associations). Habit strength was a correlate of both active and non-active gaming, indicating that both types of gaming are habitual behaviors. Although these results should be interpreted with caution because of the limitations of the study, they do provide preliminary insights into potential correlates of active and non-active gaming that can be used for further research as well as preliminary direction for the development of effective intervention strategies for replacing non-active gaming by active gaming among adolescents.

Using the theory of planned behavior to predict infant restraint use in Saudi Arabia

PubMed Central

Nelson, Anna; Modeste, Naomi N.; Marshak, Helen H.; Hopp, Joyce W.

2014-01-01

Objectives To determine whether the theory of planned behavior (TPB) predicted intent of child restraint system (CRS) use among pregnant women in the Kingdom of Saudi Arabia (KSA). Methods In this cross-sectional study conducted in Dallah Hospital, Riyadh, KSA during June-July 2013, 196 pregnant women completed surveys assessing their beliefs regarding CRS. Simultaneous observations were conducted among a different sample of 150 women to determine CRS usage at hospital discharge following maternity stay. Results Logistic regression model with TPB constructs and covariates as predictors of CRS usage intent was significant (χ2=64.986, p<0.0001) and predicted 38% of intent. There was an increase in odds of intent for attitudes (31.5%, p<0.05), subjective norm (55.3%, p<0.001), and perceived behavioral control (76.9%, p<0.001). The 3 logistic regression models testing the association of the relevant set of composite belief scores were also significant for attitudes (χ2=16.803, p<0.05), subjective norm (χ2=29.681, p<0.0001), and perceived behavioral control (χ2=20.516, p<0.05). The behavioral observation showed that none of the 150 women observed used CRS for their newborn at discharge. Conclusion: The TPB constructs were significantly and independently associated with higher intent for CRS usage. While TPB appears to be a useful tool to identify beliefs related to CRS usage intentions in KSA, the results of the separate behavioral observation indicate that intentions may not be related to the actual usage of CRS in the Kingdom. Further studies are recommended to examine this association. PMID:25228177

Community-Based Risk Communication Survey: Risk Prevention Behaviors in Communities during the H1N1 crisis, 2010.

PubMed

Kim, Soo Jeong; Han, Jin A; Lee, Tae-Yong; Hwang, Tae-Yoon; Kwon, Keun-Sang; Park, Ki Soo; Lee, Kyung Jong; Kim, Moon Shik; Lee, Soon Young

2014-02-01

The present study aimed to investigate the prevalence of and factors associated with H1N1 preventive behaviors in a community-based population. A cross-sectional study was conducted in three urban and two rural communities in Korea. Interviews were conducted with 3462 individuals (1608 men and 1854 women) aged ≥ 19 years during February-March 2010. Influenza-related information including anxiety, preventive behaviors and their perceived effectiveness, vaccination status, past influenza-like illness symptoms, and sources of and trust in information was obtained. Among 3462 participants, 173 reported experiencing influenza-like illness symptoms within the past 12 months. The mean H1N1 preventive behavior score was 25.5 ± 5.5 (out of a possible 40). The percent of participants reporting high perceived effectiveness and high anxiety was 46.2% and 21.4%, respectively. After controlling for potential confounders, H1N1 preventive behavior scores were predicted by a high (β = 3.577, p < 0.001) or moderate (β = 2.529, p < 0.001) perception of their effectiveness. Similarly, moderate (β = 1.516, p < 0.001) and high (β = 4.103, p < 0.001) anxiety scores predicted high preventive behavior scores. Effective methods of promoting population behavior change may be nationwide campaigns through mass media, as well as education and promotion by health care providers and broadcasters.

Using the lessons of behavioral economics to design more effective pay-for-performance programs.

PubMed

Mehrotra, Ateev; Sorbero, Melony E S; Damberg, Cheryl L

2010-07-01

To describe improvements in the design of pay-for-performance (P4P) programs that reflect the psychology of how people respond to incentives. Investigation of the behavioral economics literature. We describe 7 ways to improve P4P program design in terms of frequency and types of incentive payments. After discussing why P4P incentives can have unintended adverse consequences, we outline potential ways to mitigate these. Although P4P incentives are increasingly popular, the healthcare literature shows that these have had minimal effect. Design improvements in P4P programs can enhance their effectiveness. Lessons from behavioral economics may greatly enhance the design and effectiveness of P4P programs in healthcare, but future work is needed to demonstrate this empirically.

Passion for Academics and Problematic Health Behaviors

PubMed Central

BUREAU, ALEXANDER T.; RAZON, SELEN; SAVILLE, BRYAN K.; TOKAC, UMIT; JUDGE, LAWRENCE W.

2017-01-01

According to the Dualistic Model of Passion (39), passion entails valuing, liking, and spending time on an activity. The Dualistic Model also posits two types of passion for activities: harmonious passion (individual voluntarily engages in the activity) and obsessive passion (individual is compelled to engage in the activity). The purpose of the present study was to examine the possible links between college students’ passion for academic activities and problematic health behaviors including smoking, excessive drinking, exercise addiction, disordered eating, and sleepiness, which is a possible indicator of sleep deprivation. Participants (n = 502) completed a survey gauging passion type and health behaviors. Regression analyses revealed obsessive passion for academic activities was positively associated with scores on measures of excessive drinking (β = .15, p= .008), exercise addiction (β = .19, p<.001), and disordered eating (β = .17, p < .001) but was not associated with sleep deprivation (β = .07, p = .15). Harmonious passion for academic activities, in contrast, was negatively associated with excessive drinking behavior (β = −.16, p = .002) and sleep deprivation (β = −.13, p = .007) but was not associated with exercise addiction (β = .002, p = .97) and disordered eating (β = −.04, p = .37). These findings provide further support for the Dualistic Model of Passion. Students who are obsessively passionate about their academic activities are more likely to engage in poor health behaviors and, in turn, may experience greater negative outcomes than students who are harmoniously passionate about their academics. PMID:28515838

Partner Influence in Diet and Exercise Behaviors: Testing Behavior Modeling, Social Control, and Normative Body Size.

PubMed

Perry, Brea; Ciciurkaite, Gabriele; Brady, Christy Freadreacea; Garcia, Justin

2016-01-01

Previous research has documented social contagion in obesity and related health behaviors, but less is known about the social processes underlying these patterns. Focusing on married or cohabitating couples, we simultaneously explore three potential social mechanisms influencing obesity: normative body size, social control, and behavior modeling. We analyze the association between partner characteristics and the obesity-related health behaviors of focal respondents, comparing the effects of partners' body type, partners' attempts to manage respondents' eating behaviors, and partners' own health behaviors on respondents' health behaviors (physical activity, fruit and vegetable consumption, and fast food consumption). Data on 215 partners are extracted from a larger study of social mechanisms of obesity in family and community contexts conducted in 2011 in the United States. Negative binomial regression models indicate that partner behavior is significantly related to respondent behavior (p < .001), net of controls. These results are suggestive of a behavior modeling mechanism in obesity-related patterns of consumption and physical activity. In contrast, we find little support for the influence of normative body size or partner social control in this sample, though generalizations about the relevance of these processes may be inappropriate. These results underscore the importance of policies and interventions that target dyads and social groups, suggesting that adoption of exercise or diet modifications in one individual is likely to spread to others, creating a social environment characterized by mutual reinforcement of healthy behavior.

Self-efficacy and self-care behavior of Malaysian patients with type 2 diabetes: a cross sectional survey.

PubMed

Sharoni, Siti Khuzaimah Ahmad; Wu, Shu-Fang Vivienne

2012-03-01

This study investigated the association between self-efficacy and self-care behavior to determine the degree of self-efficacy and to examine differences in self-efficacy according to patient variables, including state of health, of Malaysian patients with type 2 diabetes. The sample comprised 388 patients (respondents). We collected the data from December 2010 to February 2011. We found a significant positive relationship between self-efficacy and self-care behavior (r(s) = 0.481, P < 0.001). The degree of self-efficacy was moderately high (mean = 7.570). We found significant differences between self-efficacy and education level (Wilk's Lambda = 0.918, F[12, 1008] = 2.779, P < 0.05), duration of diabetes (Wilk's Lambda = 0.954, F[8, 736] = 2.264, P < 0.05), other chronic conditions (Wilk's Lambda = 0.967, F[4, 383] = 3.304, P < 0.05) and diabetic complications (Wilk's Lambda = 0.963, F[4, 383] = 3.653, P < 0.05). Self-efficacy can be used as a model to understand self-care behavior. Individualized nursing interventions based on self-efficacy theory should be utilized in high risk diabetic patients so as to assist and improve self-care behavior. © 2012 Blackwell Publishing Asia Pty Ltd.

Synthesis, characterization and molecular weight monitoring of a novel Schiff base polymer containing phenol group: Thermal stability, conductivity and antimicrobial properties

NASA Astrophysics Data System (ADS)

Yılmaz Baran, Nuray; Saçak, Mehmet

2017-10-01

A novel Schiff base polymer containing phenol group, Poly(3-[[4-(dimethylamino)benzylidene]amino]phenol) P(3-DBAP), was prepared by oxidative polycondensation reaction of 3-[[4-(dimethylamino)benzylidene]amino]phenol (3-DBAP) using NaOCl, H2O2, O2 oxidants in aqueous alkaline medium. Yield and molecular weight distribution of P(3-DBAP) were monitored depending on oxidant types and concentration, monomer concentration and as well as polymerization temperature and time. UV-Vis, FTIR and 1HNMR techniques were used to identify the structures of Schiff base monomer and polymer. Thermal behavior of P(3-DBAP), which was determined to be thermally stable up to 1200 °C via TG-DTG techniques, was illuminated by Thermo-IR spectra recorded in the temperature range of 25-800 °C. It was determined that the electrical conductivity value of the P(3-DBAP) increased 108 fold after doped with iodine for 24 h at 60 °C according to undoped form and it was measured 4.6 × 10-4 S/cm. Also, antibacterial and antifungal activities of the monomer and polymer were assayed against Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus Feacalis, Klebsiella pneumoniae, Bacillus subtilis bacteria, and Candida albicans, Saccharomyces cerevisiae fungi.

Criminal Behavior in Frontotemporal Dementia and Alzheimer Disease

PubMed Central

Liljegren, Madeleine; Naasan, Georges; Temlett, Julia; Perry, David C.; Rankin, Katherine P.; Merrilees, Jennifer; Grinberg, Lea T.; Seeley, William W.; Englund, Elisabet; Miller, Bruce L

2015-01-01

Importance Neurodegenerative diseases can cause dysfunction of neural structures involved in judgment, executive function, emotional processing, sexual behavior, violence, and self-awareness. Such dysfunctions can lead to antisocial and criminal behavior that appears for the first time in the adult or middle-aged individual or even later in life. Objective To investigate the frequency and type of criminal behavior among patients with a diagnosed dementing disorder. Design, Setting, and Participants We conducted a retrospective medical record review of 2397 patients who were seen at the University of California, San Francisco, Memory and Aging Center between 1999 and 2012, including 545 patients with Alzheimer disease (AD), 171 patients with behavioral variant of frontotemporal dementia (bvFTD), 89 patients with semantic variant of primary progressive aphasia, and 30 patients with Huntington disease. Patient notes containing specific keywords denoting criminal behavior were reviewed. Data were stratified by criminal behavior type and diagnostic groups. Main Outcomes and Measures Frequencies of criminal behavior and χ2 statistics were calculated. Results Of the 2397 patients studied, 204 (8.5%) had a history of criminal behavior that emerged during their illness. Of the major diagnostic groups, 42 of 545 patients (7.7%) with AD, 64 of 171 patients (37.4%) with bvFTD, 24 of 89 patients (27.0%) with semantic variant of primary progressive aphasia, and 6 of 30 patients (20%) with Huntington disease exhibited criminal behavior. A total of 14% of patients with bvFTD were statistically significantly more likely to present with criminal behavior compared with 2% of patients with AD (P < .001) and 6.4% were statistically significantly more likely to exhibit violence compared with 2% of patients with AD (P = .003). Common manifestations of criminal behavior in the bvFTD group included theft, traffic violations, sexual advances, trespassing, and public urination in contrast with those in the AD group, who commonly committed traffic violations, often related to cognitive impairment. Conclusions and Relevance Criminal behavior is more common in patients with bvFTD and semantic variant of primary progressive aphasia than in those with AD and is more likely to be an early manifestation of the disorder. Judicial evaluations of criminality in the demented individual might require different criteria than the classic “insanity defense” used in the American legal system; these individuals should be treated differently by the law. The appearance of new-onset criminal behavior in an adult should elicit a search for frontal and anterior temporal brain disease and for dementing disorders. PMID:25559744

Thermoelectric properties of 80 a/o Si-20 a/o Ge alloy

NASA Technical Reports Server (NTRS)

Raag, V.

1974-01-01

This paper discusses the time and temperature dependence of the thermoelectric properties of n- and p-type 80 at. % Si-20 at. % Ge alloy. It is shown that the time-temperature behavior of the properties of both polarity types of this alloy can be described by means of a diffusion-limited dopant precipitation model due to Lifshitz and Slyozov (1961). An experimental program for the determination of the long-term behavior of the properties of the alloy is described in terms of the Lifshitz-Slyozov model, and the thermoelectric properties of the alloy are given for temperatures in the range from room temperature to 1000 C as a function of time up to and including twelve years. The data given for the p-type alloy represent the first time-dependent thermoelectric property data ever published for the p-type silicon-germanium alloys.

AC electrical conductivity and dielectric relaxation studies on n-type organic thin films of N, N‧-Dimethyl-3,4,9,10-perylenedicarboximide (DMPDC)

NASA Astrophysics Data System (ADS)

Qashou, Saleem I.; Darwish, A. A. A.; Rashad, M.; Khattari, Z.

2017-11-01

Both Alternating current (AC) conductivity and dielectric behavior of n-type organic thin films of N, N‧-Dimethyl-3,4,9,10-perylenedicarboximide (DMPDC) have been investigated. Fourier transformation infrared (FTIR) spectroscopy is used for identifying both powder and film bonds which confirm that there are no observed changes in the bonds between the DMPDC powder and evaporated films. The dependence of AC conductivity on the temperature for DMPDC evaporated films was explained by the correlated barrier hopping (CBH) model. The calculated barrier height using CBH model shows a decreasing behavior with increasing temperature. The mechanism of dielectric relaxation was interpreted on the basis of the modulus of the complex dielectric. The calculated activation energy of the relaxation process was found to be 0.055 eV.

Back-side readout semiconductor photomultiplier

DOEpatents

Choong, Woon-Seng; Holland, Stephen E

2014-05-20

This disclosure provides systems, methods, and apparatus related to semiconductor photomultipliers. In one aspect, a device includes a p-type semiconductor substrate, the p-type semiconductor substrate having a first side and a second side, the first side of the p-type semiconductor substrate defining a recess, and the second side of the p-type semiconductor substrate being doped with n-type ions. A conductive material is disposed in the recess. A p-type epitaxial layer is disposed on the second side of the p-type semiconductor substrate. The p-type epitaxial layer includes a first region proximate the p-type semiconductor substrate, the first region being implanted with p-type ions at a higher doping level than the p-type epitaxial layer, and a second region disposed on the first region, the second region being doped with p-type ions at a higher doping level than the first region.

Theoretical study of thermopower behavior of LaFeO3 compound in high temperature region

NASA Astrophysics Data System (ADS)

Singh, Saurabh; Shastri, Shivprasad S.; Pandey, Sudhir K.

2018-04-01

The electronic structure and thermopower (α) behavior of LaFeO3 compound were investigated by combining the ab-initio electronic structures and Boltzmann transport calculations. LSDA plus Hubbard U (U = 5 eV) calculation on G-type anti-ferromagnetic (AFM) configuration gives an energy gap of ˜2 eV, which is very close to the experimentally reported energy gap. The calculated values of effective mass of holes (mh*) in valance band (VB) are found ˜4 times that of the effective mass of electrons (me*) in conduction band (CB). The large effective masses of holes are responsible for the large and positive thermopower exhibited by this compound. The calculated values of α using BoltzTraP code are found to be large and positive in the 300-1200 K temperature range, which is in agreement with the experimentally reported data.

Same-Sex and Different-Sex Parent Households and Child Health Outcomes: Findings from the National Survey of Children's Health.

PubMed

Bos, Henny M W; Knox, Justin R; van Rijn-van Gelderen, Loes; Gartrell, Nanette K

2016-04-01

Using the 2011-2012 National Survey of Children's Health data set, we compared spouse/partner relationships and parent-child relationships (family relationships), parenting stress, and children's general health, emotional difficulties, coping behavior, and learning behavior (child outcomes) in households of same-sex (female) versus different-sex continuously coupled parents with biological offspring. We assessed whether associations among family relationships, parenting stress, and child outcomes were different in the 2 household types. Parental and child characteristics were matched for 95 female same-sex parent and 95 different-sex parent households with children 6 to 17 years old. One parent per household was interviewed by telephone. Multivariate analyses of variance and multiple linear regressions were conducted. No differences were observed between household types on family relationships or any child outcomes. Same-sex parent households scored higher on parenting stress (95% confidence interval = 2.03-2.30) than different-sex parent households (95% confidence interval = 1.76-2.03), p = .006. No significant interactions between household type and family relationships or household type and parenting stress were found for any child outcomes. Children with female same-sex parents and different-sex parents demonstrated no differences in outcomes, despite female same-sex parents reporting more parenting stress. Future studies may reveal the sources of this parenting stress.

Hole conduction pathways in transparent amorphous tin oxides

NASA Astrophysics Data System (ADS)

Wahila, Matthew; Lebens-Higgins, Zachary; Quackenbush, Nicholas; Piper, Louis; Butler, Keith; Hendon, Christopher; Walsh, Aron; Watson, Graeme

P-type transparent amorphous oxide semiconductors (TAOS) have yet to be sufficiently demonstrated or commercialized, severely limiting the possible device architecture of transparent and flexible oxide electronics. The lack of p-type amorphous oxide candidates mainly originates from the directional oxygen 2 p character of their topmost valence states. Previous attempts to create p-type oxides have involved hybridization of the O 2 p with metal orbitals, such as with CuAlO2 and its Cu 3 d - O 2 p hybridization. However, the highly directional nature of the utilized orbitals means that structural disorder inhibits hybridization and severely disrupts hole-conduction pathways. Crystalline stannous oxide (SnO) and other lone-pair active post-transition metal oxides can have reduced localization at the valence band edge due to complex hybridization between the O 2 p, metal p, and spherical metal s-orbitals. I will discuss our investigation of structural disorder in SnO. Using a combination of synchrotron spectroscopy, and atomistic calculations, our investigation elucidates the important interplay between atomistic and electronic structure in establishing continuous hole conduction pathways at the valence band edge of transparent amorphous oxides.

Optical and electrical properties of CuMO2 transparent p-type conductors

NASA Astrophysics Data System (ADS)

Draeseke, A. D.; Jayaraj, M. K.; Ulbrich, T.; Kroupp, M.; Tate, J.; Nagarajan, R.; Oblezov, A.; Sleight, A. W.

2001-03-01

Wide band gap oxides of the type CuMO2 with the delafossite structure are p-type conductors and many of them are transparent. Films of these p-type oxides have been grown by sputtering and thermal evaporation, and characterized electrically and optically. We present transport and optical transmission measurements for CuY_1-xCa_xO_2, CuScO_2+x and other similar materials. Conductivities are in the range 1 200 S/cm and depend on details of film preparation. The carriers are p-type as determined by thermopower measurements, and typical Seebeck coefficients are several hundred µV/K. Optical transparency varies considerably, but is about 40% at 550 nm for the highest conductivity films. Excellent transparency can be achieved at the expense of conductivity, and optimization is being studied. Band gaps derived from optical transmission are larger than 3.1 eV. Prototype all-oxide pn diodes have been fabricated. This work was partially supported by the NSF under DMR-0071727 and by the Research Corporation under RA0291.

The effect of diet on dorsal fin erosion in steelhead trout (Oncorhynchus mykiss)

USGS Publications Warehouse

Lellis, W.A.; Barrows, F.T.

1997-01-01

A 2 X 2 factorial experiment of diet type (krill vs. fish meal) and steroid supplementation (0 vs. 30 ??g 17??-methyltestosterone kg-1) was conducted to determine the effects on dorsal fin erosion in steelhead trout. Triplicate tanks of 250 fry were fed one of the four diets at a rate calculated to produce 115 g fish in 34 weeks. Fish were transferred to larger tanks when mean density index reached 0.40. Dorsal fin index (DFI, measured as mean dorsal fin height X 100/total fish length) was greater (P < 0.001) among fish fed krill-based diets than for fish fed fish-based diets at weeks 12, 22, and 34 of the trial. Added testosterone decreased (p = 0.04) DFI among fish fed the krill diet at week 12 but otherwise had no effect on fin condition. Addition of testosterone to either diet type decreased (P = 0.02) critical thermal maximum, which is a measure of fish resistance to thermal stress. The results suggest that diet composition can influence the rate of dorsal fin erosion in steelhead trout through a metabolic, behavioral, or combined change.

[Mitotic behavior of centromeres in meiosis as the fertility restoration mechanism in wheat-rye amphihaploids].

PubMed

Loginova, D B; Silkova, O G

2014-08-01

The regulation of chromosomal behavior in meiosis in partly fertile wheat-rye amphihaploids was studied using the centromere specific probes pAWRC1 and Ae. tauschii pAet6-09. Comparative analysis of the probe localization patterns in mitosis, normal meiosis in wheat Triticum aestivum L. and rye Secale cereale L., and meiosis in amphihaploids was performed. The differences in the structure of centromeres in monopolar- and bipolar- oriented chromosomes were revealed. Single dense hybridization signals were observed in the diplotene and the metaphase of the first meiotic division, while hybridization signals appeared as stretched bands with diffuse structure located across the centromere region in mitosis and the second round of meiotic division. Based upon the obtained data, we used the corresponding centromere-specific probes as a tool for the analysis of chromosomal behavior in meiosis in amphihaploids. In meiocytes with three types of chromosome behavior (reductional, equational plus reductional, and equational), dense point-like hybridization signals for the pAet6-09 probe were observed for univalents with the reductional division type and stretched bands with diffuse structure for those with the equational division type. Thus, pAet6-09 probe localization patterns suggest some structural and functional specificities of centromeres in the meiosis in wheat-rye amphihaploids that reflect special regulation of chromosomal behavior during equational division. Meiocytes with true mitotic division were also observed in anthers predominantly containing meiocytes with chromosomes undergoing equational division.

Examination of the temperature dependent electronic behavior of GeTe for switching applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Champlain, James G.; Ruppalt, Laura B.; Guyette, Andrew C.

2016-06-28

The DC and RF electronic behaviors of GeTe-based phase change material switches as a function of temperature, from 25 K to 375 K, have been examined. In its polycrystalline (ON) state, GeTe behaved as a degenerate p-type semiconductor, exhibiting metal-like temperature dependence in the DC regime. This was consistent with the polycrystalline (ON) state RF performance of the switch, which exhibited low resistance S-parameter characteristics. In its amorphous (OFF) state, the GeTe presented significantly greater DC resistance that varied considerably with bias and temperature. At low biases (<1 V) and temperatures (<200 K), the amorphous GeTe low-field resistance dramatically increased, resulting in exceptionally highmore » amorphous-polycrystalline (OFF-ON) resistance ratios, exceeding 10{sup 9} at cryogenic temperatures. At higher biases and temperatures, the amorphous GeTe exhibited nonlinear current-voltage characteristics that were best fit by a space-charge limited conduction model that incorporates the effect of a defect band. The observed conduction behavior suggests the presence of two regions of localized traps within the bandgap of the amorphous GeTe, located at approximately 0.26–0.27 eV and 0.56–0.57 eV from the valence band. Unlike the polycrystalline state, the high resistance DC behavior of amorphous GeTe does not translate to the RF switch performance; instead, a parasitic capacitance associated with the RF switch geometry dominates OFF state RF transmission.« less

Formation of p-type ZnO thin film through co-implantation

NASA Astrophysics Data System (ADS)

Chuang, Yao-Teng; Liou, Jhe-Wei; Woon, Wei-Yen

2017-01-01

We present a study on the formation of p-type ZnO thin film through ion implantation. Group V dopants (N, P) with different ionic radii are implanted into chemical vapor deposition grown ZnO thin film on GaN/sapphire substrates prior to thermal activation. It is found that mono-doped ZnO by N+ implantation results in n-type conductivity under thermal activation. Dual-doped ZnO film with a N:P ion implantation dose ratio of 4:1 is found to be p-type under certain thermal activation conditions. Higher p-type activation levels (1019 cm-3) under a wider thermal activation range are found for the N/P dual-doped ZnO film co-implanted by additional oxygen ions. From high resolution x-ray diffraction and x-ray photoelectron spectroscopy it is concluded that the observed p-type conductivities are a result of the promoted formation of PZn-4NO complex defects via the concurrent substitution of nitrogen at oxygen sites and phosphorus at zinc sites. The enhanced solubility and stability of acceptor defects in oxygen co-implanted dual-doped ZnO film are related to the reduction of oxygen vacancy defects at the surface. Our study demonstrates the prospect of the formation of stable p-type ZnO film through co-implantation.

The efficacy of cognitive behavioral therapy for Chinese people: A meta-analysis.

PubMed

Ng, Ting Kin; Wong, Daniel Fu Keung

2018-07-01

Over the past decade, cognitive behavioral therapy has been applied to an increasingly wider range of disorders and problems in Chinese societies. However, no meta-analysis has been conducted to synthesize the studies on cognitive behavioral therapy for Chinese clients. The purpose of this meta-analytic study was to examine the overall efficacy of cognitive behavioral therapy for Chinese people. A literature search was conducted using electronic databases, including Web of Science, PsycINFO and PubMed. Pooled mean effect sizes were calculated using the random-effects model. The literature search identified 55 studies with 6763 Chinese participants. The overall short-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Effect sizes were medium for anxiety, depression/well-being and caregiving stress and small for psychotic symptoms and addictive behaviors. The effects of cognitive behavioral therapy on process variables, dysfunctional thoughts and coping, were in the small range. The overall longer-term effect of cognitive behavioral therapy on the primary outcome was medium in size. Moderator analyses showed that the short-term effect was stronger for culturally adapted cognitive behavioral therapy than for unadapted cognitive behavioral therapy. Type of primary outcome, type of control group, recruitment method, study design, the format of delivery and region were found to moderate the efficacy of cognitive behavioral therapy. The findings of this study provide evidence for the overall efficacy of cognitive behavioral therapy for Chinese people and the benefit of cultural adaptation of cognitive behavioral therapy to Chinese culture.

The role of family nutritional support in Japanese patients with type 2 diabetes mellitus.

PubMed

Watanabe, Koin; Kurose, Takeshi; Kitatani, Naomi; Yabe, Daisuke; Hishizawa, Masahiro; Hyo, Takanori; Seino, Yutaka

2010-01-01

We investigated the role of family support in glycemic control by nutritional self-care behavior of Japanese patients with type 2 diabetes. One hundred twelve Japanese out-patients with type 2 diabetes were recruited for the study at Kansai Electric Power Hospital. Interviews were conducted and HbA1c and triglyceride levels were measured. HbA1c levels were significantly related to family nutritional support. Patients under 60 years old with family nutritional support showed significantly lower HbA1c than patients without family support (p<0.05). Female patients with family support showed significantly lower HbA1c than those without family support (p<0.05). In addition, male patients with family support showed significantly lower triglyceride levels than those without family support (p<0.05). In male patients, those who were supported by cooking or buying light meals showed significantly lower HbA1c than those who were supported by advice or encouragement (p<0.05). The frequency of support (every day, 2-3 days, 1 week) showed similar outcomes in glycemic control. Patients who appreciate the support and follow the advice showed lower HbA1c (6.88 +/- 0.22%) than (7.43 +/- 0.23%) patients who appreciate the advice but sometimes feel emotional barriers. Family nutritional support is useful in improving metabolic outcome of diabetic patients. Self-care practice in disease management should be carefully adjusted to the family setting of type 2 diabetic patients. Emotional barriers to family support may affect the metabolic consequences, especially in the Japanese elderly.

Aerosol jet printed p- and n-type electrolyte-gated transistors with a variety of electrode materials: exploring practical routes to printed electronics.

PubMed

Hong, Kihyon; Kim, Se Hyun; Mahajan, Ankit; Frisbie, C Daniel

2014-11-12

Printing electrically functional liquid inks is a promising approach for achieving low-cost, large-area, additive manufacturing of flexible electronic circuits. To print thin-film transistors, a basic building block of thin-film electronics, it is important to have several options for printable electrode materials that exhibit high conductivity, high stability, and low-cost. Here we report completely aerosol jet printed (AJP) p- and n-type electrolyte-gated transistors (EGTs) using a variety of different electrode materials including highly conductive metal nanoparticles (Ag), conducting polymers (polystyrenesulfonate doped poly(3,4-ethylendedioxythiophene, PEDOT:PSS), transparent conducting oxides (indium tin oxide), and carbon-based materials (reduced graphene oxide). Using these source-drain electrode materials and a PEDOT:PSS/ion gel gate stack, we demonstrated all-printed p- and n-type EGTs in combination with poly(3-hexythiophene) and ZnO semiconductors. All transistor components (including electrodes, semiconductors, and gate insulators) were printed by AJP. Both kinds of devices showed typical p- and n-type transistor characteristics, and exhibited both low-threshold voltages (<2 V) and high hole and electron mobilities. Our assessment suggests Ag electrodes may be the best option in terms of overall performance for both types of EGTs.

Auto-combustion synthesis and characterization of Mg doped CuAlO{sub 2} nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Agrawal, Shraddha, E-mail: shraddhaa32@gmail.com; Parveen, Azra; Naqvi, A. H.

2015-06-24

The synthesis of pure and Mg doped Copper aluminumoxide CuAlO{sub 2}nanoparticles, a promising p-type TCO (transparent conducting oxide) have been done bysol gel auto combustion method using NaOH as a fuel, calcinated at 600°C. The structural properties were examined by XRD and SEM techniques. The optical absorption spectra of CuAlO{sub 2} sample recorded by UV-VIS spectrophotometer in the range of 200 to 800 nm have been presented. The crystallite size was determined by powder X-ray diffraction technique. The electrical behavior of pure and Mg doped CuAlO{sub 2} has been studied over a wide range of frequencies by using complex impedance spectroscopy.Themore » variation of a.c. conductivity has been studied as function of frequency and temperature. The data taken together conclude that doping causes decreases in the ac conductivity of the nanoparticles as compared with the pure nanoparticles. Mg doping affects the optical properties and band gap.« less

Auto-combustion synthesis and characterization of Mg doped CuAlO2 nanoparticles

NASA Astrophysics Data System (ADS)

Agrawal, Shraddha; Parveen, Azra; Naqvi, A. H.

2015-06-01

The synthesis of pure and Mg doped Copper aluminumoxide CuAlO2nanoparticles, a promising p-type TCO (transparent conducting oxide) have been done bysol gel auto combustion method using NaOH as a fuel, calcinated at 600°C. The structural properties were examined by XRD and SEM techniques. The optical absorption spectra of CuAlO2 sample recorded by UV-VIS spectrophotometer in the range of 200 to 800 nm have been presented. The crystallite size was determined by powder X-ray diffraction technique. The electrical behavior of pure and Mg doped CuAlO2 has been studied over a wide range of frequencies by using complex impedance spectroscopy.The variation of a.c. conductivity has been studied as function of frequency and temperature. The data taken together conclude that doping causes decreases in the ac conductivity of the nanoparticles as compared with the pure nanoparticles. Mg doping affects the optical properties and band gap.

[A study of behavior patterns between smokers and nonsmokers].

PubMed

Kim, H S

1990-04-01

Clinical and epidemiologic studies of coronary heart disease (CHD) have from time to time over the last three decades found associations between prevalence of CHD and behavioral attributes and cigarette smoking. The main purpose of this study is reduced to major risk factor of coronary heart disease through prohibition of smoking and control of behavior pattern. The subjects consisted of 120 smokers and 90 nonsmokers who were married men older than 30 years working in officers. The officers were surveyed by means of questionnaire September 26 through October 6, 1989. The Instruments used for this study was a self-administered measurement tool composed of 59 items was made through modifications of Jenkuns Activity Survey (JAS). The Data were analysed by SAS (Statistical Analysis System) program personal computer. The statistical technique used for this study were Frequency, chi 2-test, t-test, ANOVA, Pearson Correlation Coefficient. The 15 items were chosen with items above 0.3 of the factor loading in the factor analysis. In the first factor analysis 19 factors were extracted and accounted for 86% of the total variance. However when the number of factors were limited to 3 in order to derive Jenkins classification, three factors were derived. There names are Job-Involvement, Speed & Impatience, Hard-Driving. Each of them includes 21 items, 21 and 9, respectively. The results of this study were as follow: 1. The score of the smoker group and non-smoker group in Job-Involvement (t = 5.7147, p less than 0.0001), Speed & Impatience (t = 4.6756, p less than .0001), Hard-Driving (t = 8.0822, p less than .0001) and total type A behavior pattern showed statistically significant differences (t = 8.1224, p less than .0001). 2. The score of type A behavior pattern by number of cigarettes smoked daily were not statistically significant differences. 3. The score of type A behavior pattern by duration of smoking were not significant differences. It was concluded that the relationship between smokers and non-smokers of type A behavior pattern was statistically significant difference but number of cigarettes smoked daily and duration of smoking were not significant differences. Therefore this study is needed to adequate nursing intervention of type A behavior pattern in order to elevated to educational effect for prohibition of cigarette smoking.

Effective Leadership of Surgical Teams: A Mixed Methods Study of Surgeon Behaviors and Functions.

PubMed

Stone, Juliana L; Aveling, Emma-Louise; Frean, Molly; Shields, Morgan C; Wright, Cameron; Gino, Francesca; Sundt, Thoralf M; Singer, Sara J

2017-08-01

The importance of effective team leadership for achieving surgical excellence is widely accepted, but we understand less about the behaviors that achieve this goal. We studied cardiac surgical teams to identify leadership behaviors that best support surgical teamwork. We observed, surveyed, and interviewed cardiac surgical teams, including 7 surgeons and 116 team members, from September 2013 to April 2015. We documented 1,926 surgeon/team member interactions during 22 cases, coded them by behavior type and valence (ie, positive/negative/neutral), and characterized them by leadership function (conductor, elucidator, delegator, engagement facilitator, tone setter, being human, and safe space maker) to create a novel framework of surgical leadership derived from direct observation. We surveyed nonsurgeon team members about their perceptions of individual surgeon's leadership effectiveness on a 7-point Likert scale and correlated survey measures with individual surgeon profiles created by calculating percentage of behavior types, leader functions, and valence. Surgeon leadership was rated by nonsurgeons from 4.2 to 6.2 (mean, 5.4). Among the 33 types of behaviors observed, most interactions constituted elucidating (24%) and tone setting (20%). Overall, 66% of interactions (range, 43%-84%) were positive and 11% (range, 1%-45%) were negative. The percentage of positive and negative behaviors correlated strongly (r = 0.85 for positive and r = 0.75 for negative, p < 0.05) with nonsurgeon evaluations of leadership. Facilitating engagement related most positively (r = 0.80; p = 0.03), and negative forms of elucidating, ie, criticism, related most negatively (r = -0.81; p = 0.03). We identified 7 surgeon leadership functions and related behaviors that impact perceptions of leadership. These observations suggest actionable opportunities to improve team leadership behavior. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Fully patterned p-channel SnO TFTs using transparent Al2O3 gate insulator and ITO as source and drain contacts

NASA Astrophysics Data System (ADS)

Guzmán-Caballero, D. E.; Quevedo-López, M. A.; De la Cruz, W.; Ramírez-Bon, R.

2018-03-01

SnO p-type was used as active layer to fabricate thin film transistors (TFTs) through photolithography and dry etching processes. The SnO p-type thin films (25 nm) were deposited by DC reactive sputtering with variable oxygen (O2) flow rate to then be annealed in air at 250 ◦C. Al2O3 gate dielectric (15 nm) was deposited by atomic layer deposition. Hall measurements showed p-type carrier concentration (N h ) of around 1 × 1018 cm-3 and Hall mobilities (μ Hall) between 0.35 and 2.64 cm2 V-1 s-1, depending on the O2 flow rate during deposition. The hole transport was dominated by variable-range hopping conduction. A change in the preferred crystalline orientation in the SnO films from (101) to (110) was associated with the increase in μ Hall. In addition, Raman vibrational modes at 110 and 209 cm-1 of polycrystalline SnO films showed certain dependence with the grain orientation. The SnO-based TFTs showed p-type behavior with low threshold voltages (V T ) and low sub threshold swing (SS) in the range from 1.76 to 3.50 V and 1.63 to 3.24 V/dec., respectively. The TFTs mobilities in the saturation regime (μ sat) were in the range of 0.12 and 1.32 cm2 V-1 s-1. The current on/off ratio (I ON/I OFF) was in the order of 102, approximately. The large values of the interface trap density (D IT) contributed to the high I OFF and the low I ON/I OFF of the TFTs.

Electrical isolation of component cells in monolithically interconnected modules

DOEpatents

Wanlass, Mark W.

2001-01-01

A monolithically interconnected photovoltaic module having cells which are electrically connected which comprises a substrate, a plurality of cells formed over the substrate, each cell including a primary absorber layer having a light receiving surface and a p-region, formed with a p-type dopant, and an n-region formed with an n-type dopant adjacent the p-region to form a single pn-junction, and a cell isolation diode layer having a p-region, formed with a p-type dopant, and an n-region formed with an n-type dopant adjacent the p-region to form a single pn-junction, the diode layer intervening the substrate and the absorber layer wherein the absorber and diode interfacial regions of a same conductivity type orientation, the diode layer having a reverse-breakdown voltage sufficient to prevent inter-cell shunting, and each cell electrically isolated from adjacent cells with a vertical trench trough the pn-junction of the diode layer, interconnects disposed in the trenches contacting the absorber regions of adjacent cells which are doped an opposite conductivity type, and electrical contacts.

The destructiveness of laissez-faire leadership behavior.

PubMed

Skogstad, Anders; Einarsen, Ståle; Torsheim, Torbjørn; Aasland, Merethe Schanke; Hetland, Hilde

2007-01-01

The aim of the study is to test the assumption that laissez-faire leadership behavior is not a type of zero-leadership, but a type of destructive leadership behavior that shows systematic relationships with workplace stressors, bullying at work, and psychological distress. A survey of 2,273 Norwegian employees was conducted and analyzed. Laissez-faire leadership was positively correlated with role conflict, role ambiguity, and conflicts with coworkers. Path modeling showed that these stressors mediated the effects of laissez-faire leadership on bullying at work and that the effects of laissez-faire leadership on distress were mediated through the workplace stressors, especially through exposure to bullying. The results support the assumption that laissez-faire leadership behavior is a destructive leadership behavior. (c) 2007 APA, all rights reserved.

Tuning the formation of p-type defects by peroxidation of CuAlO2 films

NASA Astrophysics Data System (ADS)

Luo, Jie; Lin, Yow-Jon; Hung, Hao-Che; Liu, Chia-Jyi; Yang, Yao-Wei

2013-07-01

p-type conduction of CuAlO2 thin films was realized by the rf sputtering method. Combining with Hall, X-ray photoelectron spectroscopy, energy dispersive spectrometer, and X-ray diffraction results, a direct link between the hole concentration, Cu vacancy (VCu), and interstitial oxygen (Oi) was established. It is shown that peroxidation of CuAlO2 films may lead to the increased formation probability of acceptors (VCu and Oi), thus, increasing the hole concentration. The dependence of the VCu density on growth conditions was identified for providing a guide to tune the formation of p-type defects in CuAlO2. Understanding the defect-related p-type conductivity of CuAlO2 is essential for designing optoelectronic devices and improving their performance.

More than just vaginal intercourse: anal intercourse and condom use patterns in the context of "main" and "casual" sexual relationships among urban minority adolescent females.

PubMed

Houston, Avril Melissa; Fang, Junyong; Husman, Constance; Peralta, Ligia

2007-10-01

Receptive anal intercourse has long been recognized as a risk factor for the transmission of HIV and STIs. Most HIV/STI prevention messages continue to emphasize penile-vaginal transmission, so many teens do not recognize anal intercourse as risky sexual behavior. This purpose of this study was to determine the prevalence of anal intercourse, and to describe the relationship between types of sexual relationships (main vs. casual), types of sexual behaviors (vaginal vs. anal sex), and types of contraception used among inner-city sexually experienced adolescents. Reproductive health histories were obtained from 350 sexually experienced adolescent females aged 12-18 years participating in a 5-year STI acquisition study at an urban health center. Baseline sexual behavior data was analyzed and described using frequencies, percentages and chi-square tests. 41% of teens and 86.5% of teens reported engaging in sexual activity with casual and main partners respectively. Sixteen percent of teens with main partners and 12% of those with casual partners engaged in receptive anal intercourse (P = 0.31). Condom use is more prevalent for both vaginal (61% vs. 32.4%, P < or = 0.0001) and anal (47.1% vs. 21.3%, P = 0.0428) intercourse in the context of casual as compared to main sexual relationships. Teens involved in a casual relationship were more likely to use anal intercourse as a form of contraception (41.2% vs. 8.5%, P = 0.0022). It is imperative that health care providers recognize that adolescents engage in anal sex, specifically inquire about their types of sexual behavior and types of sexual relationships so that anticipatory guidance regarding HIV/STI transmission risk reduction education can be tailored to meet their needs.

Temperament in infancy and behavioral and emotional problems at age 5.5: The EDEN mother-child cohort.

PubMed

Abulizi, Xian; Pryor, Laura; Michel, Grégory; Melchior, Maria; van der Waerden, Judith

2017-01-01

Early temperamental characteristics may influence children's developmental pathways and predict future psychopathology. However, the environmental context may also shape or interact with infant temperament and indirectly contribute to increased vulnerability to adverse developmental outcomes. The aim of the present study is to explore the long-term contribution of temperamental traits at twelve months of age to the presence of emotional and behavioral problems later in childhood, and whether this association varies with the child's sex, parental separation, family socioeconomic status and maternal depression. 1184 mother-child pairs from the EDEN mother-child birth cohort study based in France (2003-2011), were followed from 24-28 weeks of pregnancy to the child's fifth birthday. Infant temperament at 12 months was assessed with the Emotionality Activity and Sociability (EAS) questionnaire and behavior at 5.5 years was assessed with the Strengths and Difficulties Questionnaire (SDQ). Emotional temperament in infancy predicts children's overall behavioral scores (β = 1.16, p<0.001), emotional difficulties (β = 0.30, p<0.001), conduct problems (β = 0.51, p<0.001) and symptoms of hyperactivity/inattention (β = 0.31, p = 0.01) at 5.5 years. Infants' active temperament predicts later conduct problems (β = 0.30, p = 0.02), while shyness predicts later emotional problems (β = 0.22, p = 0.04). The association between the child's temperament in infancy and later behavior did not vary with children's own or family characteristics. An emotional temperament in infancy is associated with higher levels of emotional and behavioral difficulties at the age of 5.5 years. Children who show high emotionality early on may require early prevention and intervention efforts to divert possible adverse developmental pathways.

Temperament in infancy and behavioral and emotional problems at age 5.5: The EDEN mother-child cohort

PubMed Central

Abulizi, Xian; Pryor, Laura; Michel, Grégory; Melchior, Maria

2017-01-01

Objective Early temperamental characteristics may influence children’s developmental pathways and predict future psychopathology. However, the environmental context may also shape or interact with infant temperament and indirectly contribute to increased vulnerability to adverse developmental outcomes. The aim of the present study is to explore the long-term contribution of temperamental traits at twelve months of age to the presence of emotional and behavioral problems later in childhood, and whether this association varies with the child’s sex, parental separation, family socioeconomic status and maternal depression. Method 1184 mother-child pairs from the EDEN mother-child birth cohort study based in France (2003–2011), were followed from 24–28 weeks of pregnancy to the child’s fifth birthday. Infant temperament at 12 months was assessed with the Emotionality Activity and Sociability (EAS) questionnaire and behavior at 5.5 years was assessed with the Strengths and Difficulties Questionnaire (SDQ). Results Emotional temperament in infancy predicts children’s overall behavioral scores (β = 1.16, p<0.001), emotional difficulties (β = 0.30, p<0.001), conduct problems (β = 0.51, p<0.001) and symptoms of hyperactivity/inattention (β = 0.31, p = 0.01) at 5.5 years. Infants’ active temperament predicts later conduct problems (β = 0.30, p = 0.02), while shyness predicts later emotional problems (β = 0.22, p = 0.04). The association between the child’s temperament in infancy and later behavior did not vary with children’s own or family characteristics. Conclusion An emotional temperament in infancy is associated with higher levels of emotional and behavioral difficulties at the age of 5.5 years. Children who show high emotionality early on may require early prevention and intervention efforts to divert possible adverse developmental pathways. PMID:28199415

Childhood risk factors for criminal justice involvement in a sample of homeless people with serious mental illness.

PubMed

Desai, R A; Lam, J; Rosenheck, R A

2000-06-01

It has been suggested that criminal justice involvement among the homeless, particularly those with mental illness, is largely situational. The objective of this study was to assess, in a sample of homeless seriously mentally ill people, the prevalence of childhood conduct disorder behaviors as a risk factor for adult criminal activity as well as the extent and types of adult criminal justice contact. Data were taken from the national ACCESS program, which conducted extensive baseline interviews with 7,222 homeless seriously mentally ill adults. The interview assessed demographics, childhood risk factors for criminal activity such as conduct disorder behaviors, foster care, and parental abuse, as well as current illness severity and recent criminal justice contact. The 2-month arrest rate in this sample was much higher than national rates (11% compared with 1% annually in the general population). Although most arrests were for minor crimes (10.8%), there were also substantial rates of arrest for major (2.7%) and substance-related charges (2.0%). The prevalence of a history of conduct disorder behavior was also substantial (55% in male subjects, 40% in female subjects), and conduct disorder was a strong predictor of recent criminal justice involvement, even after controlling for other predictors of arrest (odds ratio = 1.76 for major crimes, 1.49 for minor crimes, and 1.98 for substance-related crimes). Recent literature has criticized a trend to criminalize homeless mentally ill persons for attempting to get needed food, shelter, or medical attention. However, these data indicate that at least some proportion of arrests in this population are of people who have been exhibiting antisocial behavior since early adolescence, and that early antisocial behavior is a strong predictor of all types of recent arrests in this population.

Risks associated with crack cocaine smoking among exotic dancers in Baltimore, MD.

PubMed

Sherman, Susan G; Reuben, Jacqueline; Chapman, Chris Serio; Lilleston, Pamela

2011-04-01

There is a dearth of research focusing on sex work in exotic dance clubs. We conducted a cross-sectional study to examine the prevalence and correlates of crack cocaine smoking among a sample of exotic dancers. The "block," a historical red-light district in downtown Baltimore, MD, is comprised of 30 adult-entertainment establishments. Between 01/09 and 08/09, we conducted a survey with exotic dancers (N=98). The survey explored demographic, and drug and sexual/drug risk behaviors. Bivariate and multivariate analysis was conducted using Poisson regression with robust variance estimates to examine correlates of current crack smoking. Crack cocaine smokers compared to non-crack cocaine smokers were significantly more likely to report: older age (29 vs. 23 years, respectively, p<0.0001); being White (79% vs. 50%, respectively, p=0.008); having been arrested (93% vs. 67%, respectively, p=0.008); daily alcohol consumption (36% vs. 17%, p=0.047); current heroin injection (57% vs. 13%, p<0.001); and current sex exchange (79% vs. 30%, p<0.001). In the presence of other variables, crack cocaine smokers compared to non-crack cocaine smokers were significantly older, more likely to report current heroin injection, and more likely to report current sex exchange. We found high levels of drug use and sexual risk behaviors as well as a number of risks behaviors associated with crack cocaine smoking among this very under-studied population. Targeted interventions are greatly needed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

P-type transparent conducting oxides.

PubMed

Zhang, Kelvin H L; Xi, Kai; Blamire, Mark G; Egdell, Russell G

2016-09-28

Transparent conducting oxides constitute a unique class of materials combining properties of electrical conductivity and optical transparency in a single material. They are needed for a wide range of applications including solar cells, flat panel displays, touch screens, light emitting diodes and transparent electronics. Most of the commercially available TCOs are n-type, such as Sn doped In2O3, Al doped ZnO, and F doped SnO2. However, the development of efficient p-type TCOs remains an outstanding challenge. This challenge is thought to be due to the localized nature of the O 2p derived valence band which leads to difficulty in introducing shallow acceptors and large hole effective masses. In 1997 Hosono and co-workers (1997 Nature 389 939) proposed the concept of 'chemical modulation of the valence band' to mitigate this problem using hybridization of O 2p orbitals with close-shell Cu 3d (10) orbitals. This work has sparked tremendous interest in designing p-TCO materials together with deep understanding the underlying materials physics. In this article, we will provide a comprehensive review on traditional and recently emergent p-TCOs, including Cu(+)-based delafossites, layered oxychalcogenides, nd (6) spinel oxides, Cr(3+)-based oxides (3d (3)) and post-transition metal oxides with lone pair state (ns (2)). We will focus our discussions on the basic materials physics of these materials in terms of electronic structures, doping and defect properties for p-type conductivity and optical properties. Device applications based on p-TCOs for transparent p-n junctions will also be briefly discussed.

Which Individual Therapist Behaviors Elicit Client Change Talk and Sustain Talk in Motivational Interviewing?

PubMed

Apodaca, Timothy R; Jackson, Kristina M; Borsari, Brian; Magill, Molly; Longabaugh, Richard; Mastroleo, Nadine R; Barnett, Nancy P

2016-02-01

To identify individual therapist behaviors which elicit client change talk or sustain talk in motivational interviewing sessions. Motivational interviewing sessions from a single-session alcohol intervention delivered to college students were audio-taped, transcribed, and coded using the Motivational Interviewing Skill Code (MISC), a therapy process coding system. Participants included 92 college students and eight therapists who provided their treatment. The MISC was used to code 17 therapist behaviors related to the use of motivational interviewing, and client language reflecting movement toward behavior change (change talk), away from behavior change (sustain talk), or unrelated to the target behavior (follow/neutral). Client change talk was significantly more likely to immediately follow individual therapist behaviors [affirm (p=.013), open question (p<.001), simple reflection (p<.001), and complex reflection (p<.001)], but significantly less likely to immediately follow others (giving information (p<.001) and closed question (p<.001)]. Sustain talk was significantly more likely to follow therapist use of open questions (p<.001), simple reflections (p<.001), and complex reflections (p<.001), and significantly less likely to occur following therapist use of therapist affirm (p=.012), giving information (p<.001), and closed questions (p<.001). Certain individual therapist behaviors within motivational interviewing can either elicit both client change talk and sustain talk or suppress both types of client language. Affirm was the only therapist behavior that both increased change talk and also reduced sustain talk. Copyright © 2015 Elsevier Inc. All rights reserved.

High sensitivity Schottky junction diode based on monolithically grown aligned polypyrrole nanofibers: Broad range detection of m-dihydroxybenzene.

PubMed

Ameen, Sadia; Akhtar, M Shaheer; Seo, Hyung-Kee; Shin, Hyung Shik

2015-07-30

Aligned p-type polypyrrole (PPy) nanofibers (NFs) thin film was grown on n-type silicon (100) substrate by an electrochemical technique to fabricate Schottky junction diode for the efficient detection of m-dihydroxybenzene chemical. The highly dense and well aligned PPy NFs with the average diameter (∼150-200 nm) were grown on n-type Si substrate. The formation of aligned PPy NFs was confirmed by elucidating the structural, compositional and the optical properties. The electrochemical behavior of the fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode was evaluated by cyclovoltametry (CV) and current (I)-voltage (V) measurements with the variation of m-dihydroxybenzene concentration in the phosphate buffer solution (PBS). The fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode exhibited the rectifying behavior of I-V curve with the addition of m-dihydroxybenzene chemical, while a weak rectifying I-V behavior was observed without m-dihydroxybenzene chemical. This non-linear I-V behavior suggested the formation of Schottky barrier at the interface of Pt layer and p-aligned PPy NFs/n-silicon thin film layer. By analyzing the I-V characteristics, the fabricated Pt/p-aligned PPy NFs/n-silicon Schottky junction diode displayed reasonably high sensitivity ∼23.67 μAmM(-1)cm(-2), good detection limit of ∼1.51 mM with correlation coefficient (R) of ∼0.9966 and short response time (10 s). Copyright © 2015 Elsevier B.V. All rights reserved.

Method for producing high carrier concentration p-Type transparent conducting oxides

DOEpatents

Li, Xiaonan; Yan, Yanfa; Coutts, Timothy J.; Gessert, Timothy A.; Dehart, Clay M.

2009-04-14

A method for producing transparent p-type conducting oxide films without co-doping plasma enhancement or high temperature comprising: a) introducing a dialkyl metal at ambient temperature and a saturated pressure in a carrier gas into a low pressure deposition chamber, and b) introducing NO alone or with an oxidizer into the chamber under an environment sufficient to produce a metal-rich condition to enable NO decomposition and atomic nitrogen incorporation into the formed transparent metal conducting oxide.

The relationship between parental depressive symptoms, family type, and adolescent functioning.

PubMed

Sieh, Dominik Sebastian; Sieh, Dominik Sebstian; Visser-Meily, Johanna Maria Augusta; Meijer, Anne Marie

2013-01-01

It is evident that parental depressive symptoms negatively influence adolescent behavior and various psychosocial outcomes. Certain family types like families with a chronically ill parent and single parent families are more vulnerable to parental depressive symptoms. However, the relationship between these symptoms, family type, and adolescent functioning remains largely unclear. This study examined relations between self-report of parental depressive symptoms and adolescent functioning in 86 two-parent families including a parent with a chronic medical condition, 94 families with healthy single parents, and 69 families with 2 healthy parents (comparison group). Parents completed the Beck Depression Inventory. Adolescents filled in the Youth Self-Report measuring problem behavior, and other instruments measuring psychosocial outcomes (stress, grade point average, school problems, and self-esteem). Multilevel analyses were used to examine the effects of family type, parental depressive symptoms, adolescents' gender and age, and interaction effects on adolescent functioning. The results indicated that adolescents with chronically ill and single parents had a lower grade point average (p<.01) than the comparison group. Adolescents of single parents reported more internalizing problems (p<.01) and externalizing problems (p<.05) than children from the other family types. Parental depressive symptoms were strongly related to child report of stress (p<.001). Adolescents of depressed chronically ill parents were particularly vulnerable to internalizing problems (interaction effect, p<.05). Older children and girls, and especially older girls, displayed more internalizing problems and stress. It can be concluded that growing up with a chronically ill parent in a family with 2 parents may have less impact on adolescent problem behavior than growing up in a single parent family. Health practitioners are encouraged to be attentive to the unique and combined influence of family type and parental depressive symptoms on adolescent functioning. Older and female adolescents deserve particular attention.

The association of exposure to the 2009 south war with the physical, psychological, and family well-being of Saudi children.

PubMed

El Hatw, Mohamed M; El Taher, Aly A; El Hamidi, Ahmed; Alturkait, Fawziyah A

2015-01-01

To evaluate the nutritional, psychological, behavioral, family adjustment, and psychiatric assessment of Saudi children exposed to the 2009-2010 Jazan war. This retrospective cohort study was conducted in Saudi Arabia in July 2010. One hundred and eighty-six children exposed to the South war in Jazan, and 157 unexposed children in King Khaled Military City, Hafr Al Batin were studied for evidence of malnutrition using physical measures, evaluating psychological problems using the Child Behavior Inventory, behavioral problems using the Rutter Scale A2, family adjustment using the McMaster Family adjustment device, and for psychiatric disorders. The association of different socioeconomic variables with the psychological outcome of the exposed group was also studied. The exposed children were well nourished, had more anxiety (p=0.044), better adaptation (p<0.001), less aggression (p=0.025), less deviant behavior (p=0.007), better family adjustment and had more post traumatic stress disorder, generalized anxiety, nightmares, and grief reaction. In the exposed children, females had more anxiety (p=0.006), and males had more antisocial behavior (p=0.02). Older children had less deviant behavior (p=0.005), better adaptation (p=0.007) and better planful behavior (p<0.001). Children of elder mothers had better planful behavior (p=0.039). Children from bigger families were less aggressive (p=0.049), and had less antisocial behavior (p=0.04). This study found that children exposed to the Jazan war had more anxiety. Unexpectedly they were well nourished and had higher adaptation, lower antisocial behavior, and better family adjustment. The socioeconomic status was associated with the psychological outcome. 

The association of exposure to the 2009 south war with the physical, psychological, and family well-being of Saudi children

PubMed Central

Hatw, Mohamed M. El; Taher, Aly A. El; Hamidi, Ahmed El; Alturkait, Fawziyah A.

2015-01-01

Objectives: To evaluate the nutritional, psychological, behavioral, family adjustment, and psychiatric assessment of Saudi children exposed to the 2009-2010 Jazan war. Methods: This retrospective cohort study was conducted in Saudi Arabia in July 2010. One hundred and eighty-six children exposed to the South war in Jazan, and 157 unexposed children in King Khaled Military City, Hafr Al Batin were studied for evidence of malnutrition using physical measures, evaluating psychological problems using the Child Behavior Inventory, behavioral problems using the Rutter Scale A2, family adjustment using the McMaster Family adjustment device, and for psychiatric disorders. The association of different socioeconomic variables with the psychological outcome of the exposed group was also studied. Results: The exposed children were well nourished, had more anxiety (p=0.044), better adaptation (p<0.001), less aggression (p=0.025), less deviant behavior (p=0.007), better family adjustment and had more post traumatic stress disorder, generalized anxiety, nightmares, and grief reaction. In the exposed children, females had more anxiety (p=0.006), and males had more antisocial behavior (p=0.02). Older children had less deviant behavior (p=0.005), better adaptation (p=0.007) and better planful behavior (p<0.001). Children of elder mothers had better planful behavior (p=0.039). Children from bigger families were less aggressive (p=0.049), and had less antisocial behavior (p=0.04). Conclusion: This study found that children exposed to the Jazan war had more anxiety. Unexpectedly they were well nourished and had higher adaptation, lower antisocial behavior, and better family adjustment. The socioeconomic status was associated with the psychological outcome. PMID:25630008

Quantum Transport near the Charge Neutrality Point in Inverted Type-II InAs/GaSb Field-Effect Transistors

NASA Astrophysics Data System (ADS)

Pan, W.; Klem, J. F.; Kim, J. K.; Thalakulam, M.; Cich, M. J.; Lyo, S. K.

2013-03-01

We present here our recent quantum transport results around the charge neutrality point (CNP) in a type-II InAs/GaSb field-effect transistor. At zero magnetic field, a conductance minimum close to 4e2 / h develops at the CNP and it follows semi-logarithmic temperature dependence. In quantized magnetic (B) fields and at low temperatures, well developed integer quantum Hall states are observed in the electron as well as hole regimes. Electron transport shows noisy behavior around the CNP at extremely high B fields. When the diagonal conductivity σxx is plotted against the Hall conductivity σxy, a conductivity circle law is discovered, suggesting a chaotic quantum transport behavior. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

Differences in maternal responsive and directive behavior during free play with and without aided AAC.

PubMed

Medeiros, Kara F; Cress, Cynthia J

2016-06-01

Maternal directive and responsive behaviors were compared for 25 mothers and children with complex communication needs using two types of toys (familiar and unfamiliar toys). Each type of toy play was conducted with and without a single message speech-generating communication device (SGD) programmed to say "more." Rate percentages of coded intervals for maternal directive and responsive behaviors were analyzed using repeated measures ANOVAs. Results indicated that mothers used significantly more responsive behaviors when playing with their own familiar toys than with unfamiliar toys, but no differences in directiveness between types of play. Mothers showed no differences in responsivity or directiveness when the SGD was added to play interactions, indicating that the SGD did not introduce task features that detracted from the mothers' existing levels of responsivity with their children. Clinical implications are discussed.

Girls' Aggressive Behavior

ERIC Educational Resources Information Center

Owens, Larry; Shute, Rosalyn; Slee, Phillip

2004-01-01

In contrast to boys' bullying behavior which is often overt and easily visible, girls' aggression is usually indirect and covert. Less research has been conducted on the types of bullying that girls usually engage in. Using focus groups composed of teenaged girls, Dr. Owens and colleagues examine the nature of teenage girls' indirect aggression.

Electrochemical Behavior of Pure Copper in Phosphate Buffer Solutions: A Comparison Between Micro- and Nano-Grained Copper

NASA Astrophysics Data System (ADS)

Imantalab, O.; Fattah-alhosseini, A.; Keshavarz, M. K.; Mazaheri, Y.

2016-02-01

In this work, electrochemical behavior of annealed (micro-) and nano-grained pure copper (fabricated by accumulative roll bonding process) in phosphate buffer solutions of various pH values ranging from 10.69 to 12.59 has been studied. Before any electrochemical measurements, evaluation of microstructure was obtained by optical microscope and transmission electron microscopy. To investigate the electrochemical behavior of the samples, the potentiodynamic polarization, Mott-Schottky analysis, and electrochemical impedance spectroscopy (EIS) were carried out. Potentiodynamic polarization plots and EIS measurements revealed that as a result of grain refinement, the passive behavior of the nano-grained sample was improved compared to that of annealed pure copper. Also, Mott-Schottky analysis indicated that the passive films behaved as p-type semiconductors and grain refinement did not change the semiconductor type of passive films.

Associations of disordered eating behavior with the family diabetes environment in adolescents with Type 1 diabetes.

PubMed

Caccavale, Laura J; Nansel, Tonja R; Quick, Virginia; Lipsky, Leah M; Laffel, Lori M B; Mehta, Sanjeev N

2015-01-01

To examine associations of disordered eating behaviors with aspects of the family eating and diabetes management environments among adolescents with Type 1 diabetes (T1D). Data were collected from 151 adolescents (mean age = 15.6 years) with T1D and their parents. Adolescents and parents completed self-report measures of the family eating environment (priority, atmosphere and structure/rules surrounding family meals, and the presence of restricted and special foods in the household) and diabetes family management environment (diabetes family conflict and responsibility sharing). Adolescents completed measures of parent modeling of healthy eating and disordered eating behaviors. Linear regression models were used to assess the relationship of disordered eating behaviors with aspects of the family eating and diabetes management environments. In unadjusted models, adolescent, but not parent, report of aspects of the family eating environment was associated with adolescents' disordered eating behaviors. Both adolescent and parent report of diabetes family conflict were positively associated with disordered eating behaviors. The adjusted adolescent model including all family eating and diabetes management variables accounted for 20.8% of the variance in disordered eating behaviors (p < .001, R² = .208). Factors associated with greater risk of disordered eating included being female (β = .168, p = .029), lower priority placed on family meals (β = -.273, p = .003), less parental modeling of healthy eating (β = -.197, p = .027), more food restrictions in the household β = .223, (p = .005), and greater diabetes family conflict (β = .195, p = .011). Findings suggest that aspects of the family eating environment and diabetes family conflict may represent important factors for disordered eating risk in adolescents with T1D.

Associations of disordered eating behavior with the family diabetes environment in adolescents with type 1 diabetes

PubMed Central

Caccavale, Laura J.; Nansel, Tonja R.; Quick, Virginia; Lipsky, Leah M.; Laffel, Lori M.B.; Mehta, Sanjeev N.

2014-01-01

Objective To examine associations of disordered eating behaviors with aspects of the family eating and diabetes management environments among adolescents with type 1 diabetes (T1D). Method Data were collected from 151 adolescents (M age = 15.6 years) with T1D and their parents. Adolescents and parents completed self-report measures of the family eating environment (priority, atmosphere and structure/rules surrounding family meals, and presence of restricted and special foods in the household), and diabetes family management environment (diabetes family conflict and responsibility sharing). Adolescents completed measures of parent modeling of healthy eating and disordered eating behaviors. Linear regression models were used to assess the relationship of disordered eating behaviors with aspects of the family eating and diabetes management environments. Results In unadjusted models, adolescent, but not parent, report of aspects of the family eating environment were associated with adolescents' disordered eating behaviors. Both adolescent and parent report of diabetes family conflict were positively associated with disordered eating behaviors. The adjusted adolescent model including all family eating and diabetes management variables accounted for 20.8% of the variance in disordered eating behaviors (p<.001, R2=.208). Factors associated with greater risk of disordered eating included being female (β=.168, p=.029), lower priority placed on family meals (β=-.273, p=.003), less parental modeling of healthy eating (β=-.197, p=.027), more food restrictions in the household β=.223, (p=.005), and greater diabetes family conflict (β=.195, p=.011). Conclusions Findings suggest that aspects of the family eating environment and diabetes family conflict may represent important factors for disordered eating risk in adolescents with T1D. PMID:25493461

Community-Based Risk Communication Survey: Risk Prevention Behaviors in Communities during the H1N1 crisis, 2010

PubMed Central

Kim, Soo Jeong; Han, Jin A.; Lee, Tae-Yong; Hwang, Tae-Yoon; Kwon, Keun-Sang; Park, Ki Soo; Lee, Kyung Jong; Kim, Moon Shik; Lee, Soon Young

2014-01-01

Objectives The present study aimed to investigate the prevalence of and factors associated with H1N1 preventive behaviors in a community-based population. Methods A cross-sectional study was conducted in three urban and two rural communities in Korea. Interviews were conducted with 3462 individuals (1608 men and 1854 women) aged ≥ 19 years during February–March 2010. Influenza-related information including anxiety, preventive behaviors and their perceived effectiveness, vaccination status, past influenza-like illness symptoms, and sources of and trust in information was obtained. Results Among 3462 participants, 173 reported experiencing influenza-like illness symptoms within the past 12 months. The mean H1N1 preventive behavior score was 25.5 ± 5.5 (out of a possible 40). The percent of participants reporting high perceived effectiveness and high anxiety was 46.2% and 21.4%, respectively. After controlling for potential confounders, H1N1 preventive behavior scores were predicted by a high (β = 3.577, p < 0.001) or moderate (β = 2.529, p < 0.001) perception of their effectiveness. Similarly, moderate (β = 1.516, p < 0.001) and high (β = 4.103, p < 0.001) anxiety scores predicted high preventive behavior scores. Conclusion Effective methods of promoting population behavior change may be nationwide campaigns through mass media, as well as education and promotion by health care providers and broadcasters. PMID:24955307

One-dimensional CuO nanowire: synthesis, electrical, and optoelectronic devices application

PubMed Central

2014-01-01

In this work, we presented a surface mechanical attrition treatment (SMAT)-assisted approach to the synthesis of one-dimensional copper oxide nanowires (CuO NWs) for nanodevices applications. The as-prepared CuO NWs have diameter and the length of 50 ~ 200 nm and 5 ~ 20 μm, respectively, with a preferential growth orientation along [1 1¯ 0] direction. Interestingly, nanofield-effect transistor (nanoFET) based on individual CuO NW exhibited typical p-type electrical conduction, with a hole mobility of 0.129 cm2V-1 s-1 and hole concentration of 1.34 × 1018 cm-3, respectively. According to first-principle calculations, such a p-type electrical conduction behavior was related to the oxygen vacancies in CuO NWs. What is more, the CuO NW device was sensitive to visible light illumination with peak sensitivity at 600 nm. The responsitivity, conductive gain, and detectivity are estimated to be 2.0 × 102 A W-1, 3.95 × 102 and 6.38 × 1011 cm Hz1/2 W-1, respectively, which are better than the devices composed of other materials. Further study showed that nanophotodetectors assembled on flexible polyethylene terephthalate (PET) substrate can work under different bending conditions with good reproducibility. The totality of the above results suggests that the present CuO NWs are potential building blocks for assembling high-performance optoelectronic devices. PMID:25489288

The Relation Between Depressive Symptoms and Self-Care in Patients with Diabetes Mellitus Type 2 in Kosovo.

PubMed

Sopjani, Idriz; Vehapi, Shemsedin; Gorani, Daut; Imeri, Miradije; Vitoja, Sidita; Tahiri, Shqipe

2016-12-01

The depression is a significant problem in patients with diabetes. This research is the first of it's kind conducted in the Republic of Kosovo to determine the prevalence of depression diagnosed in people with diabetes mellitus type 2 (DMT2) and interrelation between depressive symptoms and behavior of diabetes self-care (glucose monitoring, exercise, diet, and self- health care). Research was conducted in the University Clinical Center of Kosovo (UCCK), in Pristine. The sample consisted of 200 individuals. Data collection was done through structured questionnaires. HANDS (Harvard Department of Psychiatry / National Depression Screening Day Scale) questionnaire was used to assess depressive symptoms and DSMQ (The Diabetes Self-Management Questionnaire) was used to assess self-care behavior. Data analysis was run through SSPS program, version 21. The results showed that the prevalence of depression in diabetic patients was 66.5% in Kosovo. Being a woman, a resident of rural areas or with low level of education, there were significant predictors and were associated with increased chance of developing the symptoms of major depression. Significant relations were found between major depression and physical activity (p<0.05). While between major depression and management of blood glucose level, dietary control and self health care, no significant correlation was found. This paper concluded the involvement of psychological aspect in health care plan for diabetics, in order to reduce the number of individuals affected by depression, to diagnose and to treat these individuals for a better quality of life.

Perinatal western-type diet and associated gestational weight gain alter postpartum maternal mood.

PubMed

Bolton, Jessica L; Wiley, Melanie G; Ryan, Bailey; Truong, Samantha; Strait, Melva; Baker, Dana Creighton; Yang, Nancy Y; Ilkayeva, Olga; O'Connell, Thomas M; Wroth, Shelley W; Sánchez, Cristina L; Swamy, Geeta; Newgard, Christopher; Kuhn, Cynthia; Bilbo, Staci D; Simmons, Leigh Ann

2017-10-01

The role of perinatal diet in postpartum maternal mood disorders, including depression and anxiety, remains unclear. We investigated whether perinatal consumption of a Western-type diet (high in fat and branched-chain amino acids [BCAA]) and associated gestational weight gain (GWG) cause serotonin dysregulation in the central nervous system (CNS), resulting in postpartum depression and anxiety (PPD/A). Mouse dams were fed one of four diets (high-fat/high BCAA, low-fat/high BCAA, high-fat, and low-fat) prior to mating and throughout gestation and lactation. Postpartum behavioral assessments were conducted, and plasma and brain tissues assayed. To evaluate potential clinical utility, we conducted preliminary human studies using data from an extant sample of 17 primiparous women with high GWG, comparing across self-reported postpartum mood symptoms using the Edinburgh Postnatal Depression Scale (EPDS) for percent GWG and plasma amino acid levels. Mouse dams fed the high-fat/high BCAA diet gained more weight per kcal consumed, and BCAA-supplemented dams lost weight more slowly postpartum. Dams on BCAA-supplemented diets exhibited increased PPD/A-like behavior, decreased dopaminergic function, and decreased plasma tyrosine and histidine levels when assessed on postnatal day (P)8. Preliminary human data showed that GWG accounted for 29% of the variance in EPDS scores. Histidine was also lower in women with higher EPDS scores. These findings highlight the role of perinatal diet and excess GWG in the development of postpartum mood disorders.

Size dictated thermal conductivity of GaN

DOE PAGES

Thomas Edwin Beechem; McDonald, Anthony E.; Fuller, Elliot James; ...

2016-04-01

The thermal conductivity on n- and p-type doped gallium nitride (GaN) epilayers having thickness of 3-4 μm was investigated using time domain thermoreflectance (TDTR). Despite possessing carrier concentrations ranging across 3 decades (10 15 – 10 18 cm –3), n-type layers exhibit a nearly constant thermal conductivity of 180 W/mK. The thermal conductivity of p-type epilayers, in contrast, reduces from 160 to 110 W/mK with increased doping. These trends–and their overall reduction relative to bulk–are explained leveraging established scattering models where it is shown that size effects play a primary role in limiting thermal conductivity for layers even tens ofmore » microns thick. GaN device layers, even of pristine quality, will therefore exhibit thermal conductivities less than the bulk value of 240 W/mK owing to their finite thickness.« less

Electronic, transport, and optical properties of bulk and mono-layer PdSe 2

DOE PAGES

Sun, Jifeng; Shi, Hongliang; Siegrist, Theo; ...

2015-10-13

In this study, the electronic and optical properties of bulk and monolayer PdSe 2 are investigated using firstprinciples calculations. Using the modified Becke-Johnson potential, we find semiconductor behavior for both bulk and monolayer PdSe 2 with indirect gap values of 0.03 eV for bulk and 1.43 eV for monolayer, respectively. Our sheet optical conductivity results support this observation and show similar anisotropic feature in the 2D plane. We further study the thermoelectric properties of the 2D PdSe 2 using Blotzmann transport model and find interestingly high Seebeck coefficients (>200 μV/K) for both p- and n-type up to high doping levelmore » (–2 x 10 13 cm 2) with an anisotropic character in an electrical conductivity suggesting better thermoelectric performance along y direction in the plane.V« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sturza, Mihai; Malliakas, Christos D.; Bugaris, Daniel E.

A new ternary compound NaCu6Se4 was synthesized from the reaction of Cu in a molten sodium polyselenide flux. The compound crystallizes in trigonal space group Rmore » $$\\bar{3}$$m with a = 4.0465(3) Å and c = 41.493(5) Å. The crystal structure contains flat twodimensional slabs of 1/∞[Cu 6Se 4] with a unique structural arrangement, separated by Na cations. The compound contains mixed valency and has a high conductivity of ~3 × 10 3 S cm -1 at room temperature, and exhibits increasing conductivity with decreasing temperature, indicating metallic behavior. A small positive thermopower (4-11 μV K -1 from 300 to 500 K) and Hall effect measurements indicate p-type transport with a carrier concentration of ~2.8(3) × 10 21 cm -3 and a hole mobility of ~8.75 cm 2 V -1 s -1 at 300 K. NaCu 6Se 4 exhibits temperatureindependent Pauli paramagnetism.« less

Control of p-type and n-type thermoelectric properties of bismuth telluride thin films by combinatorial sputter coating technology

NASA Astrophysics Data System (ADS)

Goto, Masahiro; Sasaki, Michiko; Xu, Yibin; Zhan, Tianzhuo; Isoda, Yukihiro; Shinohara, Yoshikazu

2017-06-01

p- and n-type bismuth telluride thin films have been synthesized by using a combinatorial sputter coating system (COSCOS). The crystal structure and crystal preferred orientation of the thin films were changed by controlling the coating condition of the radio frequency (RF) power during the sputter coating. As a result, the p- and n-type films and their dimensionless figure of merit (ZT) were optimized by the technique. The properties of the thin films such as the crystal structure, crystal preferred orientation, material composition and surface morphology were analyzed by X-ray diffraction, energy-dispersive X-ray spectroscopy and atomic force microscopy. Also, the thermoelectric properties of the Seebeck coefficient, electrical conductivity and thermal conductivity were measured. ZT for n- and p-type bismuth telluride thin films was found to be 0.27 and 0.40 at RF powers of 90 and 120 W, respectively. The proposed technology can be used to fabricate thermoelectric p-n modules of bismuth telluride without any doping process.

Oxidation behavior of multiwall carbon nanotubes with different diameters and morphology

NASA Astrophysics Data System (ADS)

Mazov, Ilya; Kuznetsov, Vladimir L.; Simonova, Irina A.; Stadnichenko, Andrey I.; Ishchenko, Arkady V.; Romanenko, Anatoly I.; Tkachev, Evgeniy N.; Anikeeva, Olga B.

2012-06-01

Multiwall carbon nanotubes (MWNT) with three medium diameters (20-22, 9-13, and 6-8 nm) and different morphology were chemically oxidized using concentrated nitric acid, mixture of nitric and sulfuric acids ("mélange" solution) and mixture of sulfuric acid and hydrogen peroxide ("piranha" solution). Influence of MWNT type and structure as well as type of oxidizer on the surface composition and structure of nanotubes after oxidation was investigated. Acid-base titration, X-ray photoelectron spectroscopy and thermal gravimetric analysis were used for quantitative and qualitative investigation of surface group composition of initial and oxidized nanotubes. Amount of oxygen-containing groups on the surface of oxidized MWNT depends on the type of initial MWNT. It was found that ratio of different oxygen containing groups is less dependent on the type of oxidizer. Electrophysical properties of initial and oxidized nanotubes were investigated in temperature range 4-293 K and main types of electrical conductivity were determined. It was shown that oxidation results in decrease in electrical conductivity of all samples with simultaneous change in the conductivity mechanism. Dispersive behavior of initial and oxidized nanotubes in different commonly used solvents was investigated. It was shown that oxidation leads to the improvement of sedimentation stability of MWNT in polar solvents.

Influence of the ``second gap'' on the optical absorption of transparent conducting oxides

NASA Astrophysics Data System (ADS)

Ha, Viet-Anh; Waroquiers, David; Rignanese, Gian-Marco; Hautier, Geoffroy

Transparent conducting oxides (TCOs) are critical to many technologies (e.g., thin-film solar cells, flat-panel displays or organic light-emitting diodes). TCOs are heavily doped (n or p-type) oxides that satisfy many design criteria such as high transparency to visible light (i.e., a band gap > 3 eV), high concentration and mobility of carriers (leading to high conductivity), ... In such (highly doped) systems, optical transitions from the conduction band minimum to higher energy bands in n-type or from lower energy bands to the valence band maximum in p-type are possible and can degrade transparency. In fact, it has been claimed that a high energy (> 3eV) for any of these transitions made possible by doping, commonly referred as a high ``second gap'', is a necessary design criterion for high performance TCOs. Here, we study the influence of this second gap on the transparency of doped TCOs by using ab initio calculations within the random phase approximation (RPA) for several well-known p-type and n-type TCOs. Our work highlights how the second gap affects the transparency of doped TCOs, shining light on more accurate design criteria for high performance TCOs.

[The influence of cognitive-behavioral therapy on the P300 potential in children with psychogenic nonepileptic seizures and tension headache].

PubMed

Stolarska-Weryńska, Urszula; Steczkowska, Małgorzata; Kaciński, Marek

2016-01-01

Explaining associations between neurophysiological and neuropsychological parameteres in children and improving the measurement methods would lead to a better understanding of the pathogenesis and course of psychosomatic disease. Goal: clinical assessment of the efficacy of cognitive-behavioral therapy in the treatment of psychogenic no- nepileptic seizures and tension type headaches in children. Determining the influence of cognitive behavioral therapy on the cognitive P300 potential and whether P300 parameters in children correlate with neuropsychological parameters. 20 children with nonepileptic psychogenic seizures and 30 children with tension type headaches, aged 11.3 - 17.11 years. The final diagnosis was made in the Paediatric Neurology Clinic. The P300 examination was performed before/after therapy, with/without hyperventilation. A fixed structure therapy was implemented (10 sessions, 90 minutes each), during two weeks of hospitalization or in an outpatient clinic (9 children with tension type headache). The psychological assessment comprised of temperament questionnaires, auditory and visual memory trials, executive function and attention trials, and in some cases also intelligence testing. More significant correlations were found in children with psychogenic seizures: attention parameters correlated negatively with reaction time, and this correlation tended to fade in the second examination, after psychotherapy. In children with tension type headache a statistically insignificant tendency was found of a positive correlation between those parameters. Medium P300 parameteres in this group were better. In 17/20 of children with psychogenic seizures a clinical improvement was observed, in 3 children the symptoms persisted in a 6 month follow up, but of a lower frequency. In 11/27 of chil- dren with tension headache the symptoms persisted, also with a lower frequency. cognitive-behavioral therapy is effective in the reduction of symptoms in many cases of psychogenic seizures and chronic tension type headache.

Oxygen Transport Membranes

DOE Office of Scientific and Technical Information (OSTI.GOV)

S. Bandopadhyay

2008-08-30

The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air asmore » a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the small polaron conduction mechanism. Scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) were used to develop strategies to detect and characterize vacancy creation, dopant segregations and defect association in the oxygen conducting membrane material. The pO{sub 2} and temperature dependence of the conductivity, non-stoichiometry and thermal-expansion behavior of compositions with increasing complexity of substitution on the perovskite A and B sites were studied. Studies with the perovskite structure show anomalous behavior at low oxygen partial pressures (<10{sup -5} atm). The anomalies are due to non-equilibrium effects and can be avoided by using very strict criteria for the attainment of equilibrium. The slowness of the oxygen equilibration kinetics arises from two different mechanisms. In the first, a two phase region occurs between an oxygen vacancy ordered phase such as brownmillerite SrFeO{sub 2.5} and perovskite SrFeO{sub 3-x}. The slow kinetics is associated with crossing the two phase region. The width of the miscibility gap decreases with increasing temperature and consequently the effect is less pronounced at higher temperature. The preferred kinetic pathway to reduction of perovskite ferrites when the vacancy concentration corresponds to the formation of significant concentrations of Fe{sup 2+} is via the formation of a Ruddlesden-Popper (RP) phases as clearly observed in the case of La{sub 0.5}Sr{sub 0.5}FeO{sub 3-x} where LaSrFeO{sub 4} is found together with Fe. In more complex compositions, such as LSFTO, iron or iron rich phases are observed locally with no evidence for the presence of discrete RP phase. Fracture strength of tubular perovskite membranes was determined in air and in reducing atmospheric conditions. The strength of the membrane decreased with temperature and severity of reducing conditions although the strength distribution (Weibull parameter, m) was relatively unaltered. Surface and volume dominated the fracture origins and the overall fracture was purely transgranular. The dual phase membranes have been evaluated for structural properties. An increasing crack growth resistance was observed for the membranes heat-treated at 1000 C in air and N{sub 2} with increasing crack length. The combined effect of thermal and elastic mismatch stresses on the crack path was studied and the fracture behavior of the dual phase composite at the test conditions was analyzed. Ceramic/metal (C/M) seals are needed to form a leak-tight interface between the OTM and a nickel-base super alloy. It was concluded that Ni-based brazing alloys provided the best option in terms of brazing temperature and final operating conditions after analyzing several possible brazing systems. A mechanical testing procedure has been developed. This model was tested with model ceramic/metal systems but it is expected to be useful for testing concentric perovskite/metal seals.« less

Smoking Behaviors and Attitudes Among Clients and Staff at New York Addiction Treatment Programs Following a Smoking Ban: Findings After 5 Years.

PubMed

Pagano, Anna; Guydish, Joseph; Le, Thao; Tajima, Barbara; Passalacqua, Emma; Soto-Nevarez, Arturo; Brown, Lawrence S; Delucchi, Kevin L

2016-05-01

Addiction treatment clients are more likely to die of tobacco-related diseases than of alcohol or illicit drug-related causes. We aimed to assess smoking behavior, and smoking-related attitudes and services, in New York addiction treatment programs before a statewide smoking ban in treatment facilities was implemented (2008), 1 year (2009) and 5 years after implementation (2013). We conducted surveys at each time point with clients (N = 329, 341, and 353, respectively) and staff (N = 202, 203, and 166, respectively) from five residential and two methadone maintenance programs in New York State. At each data collection wave, questionnaires measured smoking behavior as well as smoking-related knowledge, attitudes, and experiences with tobacco cessation services as part of addiction treatment. Staff smoking prevalence decreased from 35.2% in 2008 to 21.8% in 2013 (P = .005) while client smoking prevalence over the same period was unchanged (68.1% vs. 66.0%, P = .564). Among clients who smoked, mean cigarettes per day decreased from 13.7 (SD = 8.38) to 10.2 (SD = 4.44; P < .001). There were significant time-by-treatment-type interactions for client tobacco-related attitudes and cessation services received; and for staff self-efficacy and cessation services provided. In residential programs, scores for most items decreased (became less positive) in 2009 followed by a partial rebound in 2013. Methadone program scores tended to rise (become more positive) throughout the study period. Staff and clients may respond differentially to tobacco-free policies depending on type of treatment program, and this finding may help to inform the implementation of tobacco-free policies in other statewide addiction treatment systems. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

An Assessment of the Effects of Hydrotherapy During the Active Phase of Labor on the Labor Process and Parenting Behavior.

PubMed

Tuncay, Semra; Kaplan, Sena; Moraloglu Tekin, Ozlem

2017-12-01

This study was conducted to assess the effect on labor process and parenting behavior of hydrotherapy applied during the active phase of labor. This quasi-experimental study was conducted by using an equivalent comparison group ( n = 40). The participants in the experimental group whose cervical dilation was 5 cm were taken to the hydrotherapy tub. This application continued until cervical dilation reached 10 cm. The Participants Questionnaire, The Birth Follow-up Questionnaire, The Postpartum ]collection tools. The duration of the active phase and second stage of labor was extremely short in the experimental group in comparison with the equivalent comparison group ( p = .001). The Visual Analogue Scale (VAS) scores of the experimental group were lower than those of the equivalent comparison group when cervical dilation was 6 cm and 10 cm ( p = .001). The experimental group also displayed more positive parenting behavior and positive labor feeling ( p = .001).

Psilocybin occasioned mystical-type experiences: Immediate and persisting dose-related effects

PubMed Central

Griffiths, R. R.; Johnson, M.W.; Richards, W. A.; Richards, B.D.; McCann, U.; Jesse, R.

2012-01-01

Rationale This dose-effect study extends previous observations showing that psilocybin can occasion mystical-type experiences having persisting positive effects on attitudes, mood, and behavior. Objectives This double-blind study evaluated psilocybin (0, 5, 10, 20, 30 mg/70 kg, p.o.) administered under supportive conditions. Methods Participants were 18 adults (17 hallucinogen-naïve). Five 8-hour sessions were conducted individually for each participant at 1-month intervals. Participants were randomized to receive the four active doses in either ascending or descending order (9 participants each). Placebo was scheduled quasi-randomly. During sessions volunteers used eyeshades and were instructed to direct their attention inward. Volunteers completed questionnaires assessing effects immediately after and 1 month after each session, and at 14 months follow-up. Results Psilocybin produced acute perceptual and subjective effects including, at 20 and/or 30 mg/70 kg, extreme anxiety/fear (39% of volunteers) and/or mystical-type experience (72% of volunteers). One month after sessions at the two highest doses, volunteers rated the psilocybin experience as having substantial personal and spiritual significance, and attributed to the experience sustained positive changes in attitudes, mood, and behavior, with the ascending dose sequence showing greater positive effects. At 14 months, ratings were undiminished and were consistent with changes rated by community observers. Both the acute and persisting effects of psilocybin were generally a monotonically increasing function of dose, with the lowest dose showing significant effects. Conclusions Under supportive conditions, 20 and 30 mg/70 kg psilocybin occasioned mystical-type experiences having persisting positive effects on attitudes, mood and behavior. Implications for therapeutic trials are discussed. PMID:21674151

Frequency and foraging behavior of Apis mellifera in two melon hybrids in Juazeiro, state of Bahia, Brazil.

PubMed

Kiill, Lúcia H P; Siqueira, Kátia M M; Coelho, Márcia S; Silva, Tamires A; Gama, Diego R S; Araújo, Diego C S; Pereira Neto, Joaquim

2014-12-01

The study was carried out to verify if there are differences in foraging frequency and behavior of Apis mellifera in two melon hybrids (10:00 - 'Yellow melon' and Sancho -'Piel de Sapo') in the municipality of Juazeiro, state of Bahia, Brazil. The frequency, behavior of visitors and the floral resource foraged were registered from 5:00 am to 6:00 pm. There was a significant difference in the frequency of visits when comparing hydrids (F = 103.74, p <0.0001), floral type (F = 47.25, p <0.0001) and resource foraged (F = 239.14, p <0.0001). The flowers of Sancho were more attractive to A. mellifera when compared with hybrid 10:00, which may be correlated to the morphology and floral resources available. This could be solved with scaled planting, avoiding the overlapping of flowering of both types.

Changes in physical activity and travel behaviors in residents of a mixed-use development.

PubMed

Mumford, Karen G; Contant, Cheryl K; Weissman, Jennifer; Wolf, Jean; Glanz, Karen

2011-11-01

Mixed-use developments may be especially promising settings for encouraging walking and other types of physical activity. This study examined the physical activity and travel behaviors of individuals before and after they relocated to Atlantic Station, a mixed-use redevelopment community in metropolitan Atlanta. A survey study was conducted to compare the behaviors, experiences, and attitudes of Atlantic Station residents before and after moving to a mixed-use neighborhood. Data were collected in 2008 and 2009 and analyzed in 2010. Key dependent variables were self-reported physical activity and travel behaviors including walking for recreation and transport, automobile use, and use of public transportation. Study participants included 101 adult residents of Atlantic Station, most of whom were female, young, and well educated. There were significant increases in walking for recreation or fitness (46%-54%; p<0.05) and walking for transportation (44%-84%; p<0.001) after moving into the mixed-use development. Respondents also reported reduced automobile travel and increased time spent using public transportation after moving to Atlantic Station. Because this study used individuals as their own controls, there is more control over confounding lifestyle variables compared to cross-sectional studies of individuals living in different neighborhoods. Adults who move to a denser, mixed-use neighborhood increase their levels of walking for both recreation and transportation, decrease their automobile travel, and increase their use of public transportation. Copyright © 2011 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Highly spectrum-selective ultraviolet photodetector based on p-NiO/n-IGZO thin film heterojunction structure.

PubMed

Li, H K; Chen, T P; Hu, S G; Li, X D; Liu, Y; Lee, P S; Wang, X P; Li, H Y; Lo, G Q

2015-10-19

Ultraviolet photodetector with p-n heterojunction is fabricated by magnetron sputtering deposition of n-type indium gallium zinc oxide (n-IGZO) and p-type nickel oxide (p-NiO) thin films on ITO glass. The performance of the photodetector is largely affected by the conductivity of the p-NiO thin film, which can be controlled by varying the oxygen partial pressure during the deposition of the p-NiO thin film. A highly spectrum-selective ultraviolet photodetector has been achieved with the p-NiO layer with a high conductivity. The results can be explained in terms of the "optically-filtering" function of the NiO layer.

Influence of defects and dopants on the photovoltaic performance of Bi 2S 3: First-principles insights

DOE PAGES

Han, Dan; Du, Mao -Hua; Dai, Chen -Min; ...

2017-02-23

Bi 2S 3 has attracted extensive attention recently as a light-absorber, sensitizer or electron acceptor material in various solar cells. Using first-principles calculations, we find that the photovoltaic efficiency of Bi 2S 3 solar cells is limited by its intrinsic point defects, i.e., both S vacancy and S interstitial can have high concentration and produce deep defect levels in the bandgap, leading to non-radiative recombination of electron–hole carriers and reduced minority carrier lifetime. Unexpectedly most of the intrinsic defects in Bi 2S 3, including even the S interstitial, act as donor defects, explaining the observed n-type conductivity and also causingmore » the high p-type conductivity impossible thermodynamically. Doping in Bi 2S 3 by a series of extrinsic elements is studied, showing that most of the dopant elements such as Cu, Br and Cl make the material even more n-type and only Pb doping makes it weakly p-type. Based on this, we propose that the surface region of n-type Bi 2S 3 nanocrystals in p-PbS/n-Bi 2S 3 nano-heterojunction solar cells may be type-inverted into p-type due to Pb doping, with a buried p–n junction formed in the Bi 2S 3 nanocrystals, which provides a new explanation to the longer carrier lifetime and higher efficiency. Lastly, considering the relatively low conduction band and high n-type conductivity, we predict that Cu, Br and Cl doped Bi 2S 3 may be an ideal n-type electron acceptor or counter electrode material, while the performance of Bi 2S 3 as a light-absorber or sensitizer material is intrinsically limited.« less

10th Annual Systems Engineering Conference: Volume 2 Wednesday

DTIC Science & Technology

2007-10-25

intelligently optimize resource performance. Self - Healing Detect hardware/software failures and reconfigure to permit continued operations. Self ...Types Wake Ice WEAPON/PLATFORM ACOUSTICS Self -Noise Radiated Noise Beam Forming Pulse Types Submarines, surface ships, and platform sensors P r o p P r o...Computing Self -Protecting Detect internal/external attacks and protect it’s resources from exploitation. Self -Optimizing Detect sub-optimal behaviors and

Physical and photoelectrochemical properties of spherical nanoparticles of α-AgBiS2

NASA Astrophysics Data System (ADS)

Bellal, B.; Berger, M. H.; Trari, M.

2017-10-01

We have investigated the physical and photo electrochemical properties of α-AgBiS2 (schapbachite), synthesized from Bi2S3 and Ag2S in evacuated Pyrex ampoule at 550 °C. The precursors are prepared by precipitation from nitrates in ethylene glycol using thiourea as complexing agent and sulfide source. AgBiS2 crystallizes in a rock salt structure (Fm-3m). The transmission electron micrograph shows spherical nanoparticles with an average size of 30 nm, a value very close to that obtained from the Williamson-Hall plot of the XRD powder pattern (33.06±1.28 nm). HRTEM gives inter reticular distance of 0.33 nm, a value in excellent agreement with that of the SAED analysis (d111=0.3276 nm). The diffuse reflectance spectrum indicates a direct optical transition of 0.89 eV. The thermal variation of the electrical conductivity is characteristic of semiconducting behavior with activation energy of 0.20 eV, electron mobility (μ300K) of 2.43 × 10-4 cm2 V-1 s-1 and an effective mass of 2.88 mo. The intensity-potential J(V) curve in alkaline medium (pH 10.2) shows a good electrochemical stability. The dark capacitance (C-2-V) exhibits a linear behavior, characteristic of n-type conduction (dC-2/dE>0), from which a flat band potential of 0.33 VSCE and an electrons density of 2.57 × 1021 cm-3 are determined. The valence band derives from S2-: 3p states while the conduction band is made up mainly of Ag+: 5 s orbital. The electrochemical impedance spectroscopy (EIS), measured in the dark and under illumination over the frequency range (10-3-105 Hz), indicates the contribution of both the bulk and grain boundaries. An equivalent electrical circuit was simulated from the Nyquist diagram at pH 10, indicating the bulk contribution in the transport mechanism.

Investigation and Manipulation of Different Analog Behaviors of Memristor as Electronic Synapse for Neuromorphic Applications.

PubMed

Wang, Changhong; He, Wei; Tong, Yi; Zhao, Rong

2016-03-14

Low-power and high-density electronic synapse is an important building block of brain-inspired systems. The recent advancement in memristor has provided an opportunity to advance electronic synapse design. However, a guideline on designing and manipulating the memristor's analog behaviors is still lacking. In this work, we reveal that compliance current (Icomp) of electroforming process played an important role in realizing a stable analog behavior, which is attributed to the generation of conical-type conductive filament. A proper Icomp could result in a large conductance window, good stability, and low voltage analog switching. We further reveal that different pulse conditions can lead to three analog behaviors, where the conductance changes in monotonic increase, plateau after initial jump, and impulse-like shape, respectively. These behaviors could benefit the design of electronic synapse with enriched learning capabilities. This work will provide a useful guideline for designing and manipulating memristor as electronic synapses for brain-inspired systems.

Investigation and Manipulation of Different Analog Behaviors of Memristor as Electronic Synapse for Neuromorphic Applications

NASA Astrophysics Data System (ADS)

Wang, Changhong; He, Wei; Tong, Yi; Zhao, Rong

2016-03-01

Low-power and high-density electronic synapse is an important building block of brain-inspired systems. The recent advancement in memristor has provided an opportunity to advance electronic synapse design. However, a guideline on designing and manipulating the memristor’s analog behaviors is still lacking. In this work, we reveal that compliance current (Icomp) of electroforming process played an important role in realizing a stable analog behavior, which is attributed to the generation of conical-type conductive filament. A proper Icomp could result in a large conductance window, good stability, and low voltage analog switching. We further reveal that different pulse conditions can lead to three analog behaviors, where the conductance changes in monotonic increase, plateau after initial jump, and impulse-like shape, respectively. These behaviors could benefit the design of electronic synapse with enriched learning capabilities. This work will provide a useful guideline for designing and manipulating memristor as electronic synapses for brain-inspired systems.

Carrier removal and defect behavior in p-type InP

NASA Technical Reports Server (NTRS)

Weinberg, I.; Swartz, C. K.; Drevinsky, P. J.

1992-01-01

A simple expression, obtained from the rate equation for defect production, was used to relate carrier removal to defect production and hole trapping rates in p-type InP after irradiation by 1-MeV electrons. Specific contributions to carrier removal from defect levels H3, H4, and H5 were determined from combined deep-level transient spectroscopy (DLTS) and measured carrier concentrations. An additional contribution was attributed to one or more defects not observed by the present DLTS measurements. The high trapping rate observed for H5 suggests that this defect, if present in relatively high concentration, could be dominant in p-type InP.

Transformation from insulating p-type to semiconducting n-type conduction in CaCu3Ti4O12-related Na(Cu5/2Ti1/2)Ti4O12 ceramics

NASA Astrophysics Data System (ADS)

Li, Ming; Sinclair, Derek C.

2013-07-01

A double doping mechanism of Na+ + 1/2 Ti4+ → Ca2+ + 1/2 Cu2+ on the general formula Ca1-xNax(Cu3-x/2Tix/2)Ti4O12 has been used to prepare a series of isostructural CaCu3Ti4O12 (CCTO)-type perovskites. A complete solid solution exists for 0 ≤ x ≤ 1 and all compositions exhibit incipient ferroelectric behaviour with higher than expected intrinsic relative permittivity. Although CCTO ceramics typically exhibit n-type semiconductivity (room temperature, RT, resistivity of ˜10-100 Ω cm), Na(Cu5/2Ti1/2)Ti4O12 (NCTO) ceramics sintered at 950 °C consist of two insulating bulk phases (RT resistivity > 1 GΩ cm), one p-type and the other n-type. With increasing sintering temperature/period, the p-type phase transforms into the n-type phase. During the transformation, the resistivity and activation energy for electrical conduction (Ea ˜ 1.0 eV) of the p-type phase remain unchanged, whereas the n-type phase becomes increasingly conductive with Ea decreasing from ˜ 0.71 to 0.11 eV with increasing sintering temperature. These changes are attributed to small variations in stoichiometry that occur during high temperature ceramic processing with oxygen-loss playing a crucial role.

I Should but I Can't: Controlled Motivation and Self-Efficacy Are Related to Disordered Eating Behaviors in Adolescents With Type 1 Diabetes.

PubMed

Eisenberg, Miriam H; Lipsky, Leah M; Dempster, Katherine W; Liu, Aiyi; Nansel, Tonja R

2016-11-01

Among adolescents with type 1 diabetes, disordered eating behaviors (DEBs) are more prevalent and have more serious health implications than in adolescents without diabetes, necessitating identification of modifiable correlates of DEB in this population. This study hypothesized that (1) autonomous motivation and (2) controlled motivation for healthy eating (i.e., eating healthfully because it is important to oneself vs. important to others, respectively) are associated with DEB among adolescents with type 1 diabetes. The third hypothesis was that baseline healthy eating self-efficacy moderates these associations. Adolescents with type 1 diabetes (n = 90; 13-16 years) participating in a behavioral nutrition intervention efficacy trial reported DEB, controlled and autonomous motivation, and self-efficacy at baseline, 6, 12, and 18 months. Linear-mixed models estimated associations of controlled and autonomous motivation with DEB, adjusting for treatment group, body mass index, socioeconomic status, age, and gender. Separate models investigated the interaction of self-efficacy with each motivation type. Controlled motivation was positively associated with DEB (B = 2.18 ± .33, p < .001); the association was stronger for those with lower self-efficacy (B = 3.33 ± .55, p < .001) than those with higher self-efficacy (B = 1.36 ± .36, p < .001). Autonomous motivation was not associated with DEB (B = -.70 ± .43, p = .11). Findings identify controlled motivation for healthy eating as a novel correlate of DEB among adolescents with type 1 diabetes and show that self-efficacy can modify this association. Motivation and self-efficacy for healthy eating represent potential intervention targets to reduce DEB in adolescents with type 1 diabetes. Published by Elsevier Inc.

The association between elevated blood lead levels and violent behavior during late adolescence: The South African Birth to Twenty Plus cohort.

PubMed

Nkomo, Palesa; Mathee, Angela; Naicker, Nisha; Galpin, Jacky; Richter, Linda M; Norris, Shane A

2017-12-01

Epidemiological studies have shown the adverse neuro-behavioral health effects of lead exposure among children, in particular. However, there is lack evidence in this regard from developing countries. The main aim of this study was to assess the association between blood lead levels (BLLs) during early adolescence and violent behavior in late adolescence. Our study sample from the Birth to Twenty Plus cohort in Soweto-Johannesburg, South Africa included 1332 study participants (684 females). BLLs were measured using blood samples collected at age 13years. Violent behavior was evaluated using data collected at ages 15 to 16years using the Youth Self Report questionnaire. First, bivariate analysis was used to examine data for an association between lead exposure in early adolescence and violent behavior items during late adolescence. Principal Component Analysis (PCA) was used for dimensionality reduction and six violent behavior components were derived. Data were further analyzed for an association between BLLs at age 13years and violent behavior using PCA derived components; to determine the specific type(s) of violent behavior associated with lead exposure. Median whole BLLs were 5.6μg/dL (p<0.001). Seventy five percent of males and 50% of females had BLLs≥5μg/dL. BLLs ranging from 5 to 9.99μg/dL were associated with physical violence (p=0.03) and BLLs≥10μg/dL were associated physical violence and fighting (p=0.02 and p=0.01, respectively). When data were analyzed using continuous BLLs physical violence was associated with lead exposure (p<0.0001). Furthermore, males were more likely to be involved in violence using a weapon (p=0.01), physical violence (p<0.0001), and robbing others (p<0.05) compared to females. The results from this study show the severe nature of violent behavior in late adolescence associated with childhood lead exposure. They highlight the urgent need for preventive measures against lead exposure among children in low or middle income countries such as South Africa. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intrathecal P/Q- and R-type calcium channel blockades on spinal substance P release and c-Fos expression

PubMed Central

Terashima, Tetsuji; Xu, Qinghao; Yamaguchi, Shigeki; Yaksh, Tony L.

2013-01-01

Intrathecal (IT) studies have shown that several voltage sensitive calcium channels (VSCCs), such as the L-, N- and T-type may play roles in nociception and that of these only the N-type regulates primary afferent substance P (SP) release. However, the actions of other VSCCs at the spinal level are not well known. We investigated the roles of spinal P/Q- and R-type VSCCs, by IT administration of R-type (SNX-482) and P/Q-type (ω-agatoxin IVA) VSCC blockers on intraplantar formalin-evoked flinching, SP release from primary afferents and c-Fos expression in spinal dorsal horn. Intraplantar injection of formalin (2.5%, 50 µL) produced an intense, characteristic biphasic paw flinching response. In rats with IT catheters, IT SNX-482 (0.5 µg) reduced formalin-evoked paw flinching in both phase 1 and 2 compared with vehicle. Intraplantar formalin caused robust neurokinin 1 receptor (NK1r) internalization (indicating SP release) and c-Fos expression in the ipsilateral dorsal horn, which were blocked by IT SNX-482. IT ω-agatoxin IVA (0.03, 0.125 and 0.5 µg) did not reduce formalin-evoked paw flinching or c-Fos expression at any doses, with higher doses resulting in motor dysfunction. Thus, we demonstrated that blockade of spinal R-type, but not P/Q type VSCCs attenuated formalin-induced pain behavior, NK1r internalization and c-Fos expression in the superficial dorsal horn. This study supports a role for Cav2.3 in presynaptic neurotransmitter release from peptidergic nociceptive afferents and pain behaviors. PMID:23810829

Efficiency degradation behaviors of current/thermal co-stressed GaN-based blue light emitting diodes with vertical-structure

NASA Astrophysics Data System (ADS)

Liu, Lilin; Ling, Minjie; Yang, Jianfu; Xiong, Wang; Jia, Weiqing; Wang, Gang

2012-05-01

With this work, we demonstrate a three-stage degradation behavior of GaN based LED chips under current/thermal co-stressing. The three stages in sequence are the initial improvement stage, the platform stage, and the rapid degradation stage, indicating that current/thermal co-stressing activates positive effects and negative ones simultaneously, and the dominant degradation mechanisms evolve with aging time. Degradation mechanisms are discussed. Electric current stress has dual characters: damaging the active layers by generating defects and at the same time improving the p-type conductivity by activating the Mg-dopant. High temperature stresses will promote the effects from electric current stresses. The activation of the Mg-dopant will saturate, whereas the generation of defects is carried on in a progressive way. Other mechanisms, such as deterioration of ohmic contacts, also operate. These mechanisms compete/cooperate with each other and evolve with aging time, resulting in the observed three-stage degradation behavior. There exist risks to predict the lifetime of LEDs by a model with a constant accelerated factor.

Effect of Footwear Modifications on Oscillations at the Achilles Tendon during Running on a Treadmill and Over Ground: A Cross-Sectional Study.

PubMed

Meinert, Ilka; Brown, Niklas; Alt, Wilfried

2016-01-01

Achilles tendon injuries are known to commonly occur in runners. During running repeated impacts are transferred in axial direction along the lower leg, therefore possibly affecting the oscillation behavior of the Achilles tendon. The purpose of the present study was to explore the effects of different footwear modifications and different ground conditions (over ground versus treadmill) on oscillations at the Achilles tendon. Oscillations were measured in 20 male runners using two tri-axial accelerometers. Participants ran in three different shoe types on a treadmill and over ground. Data analysis was limited to stance phase and performed in time and frequency space. Statistical comparison was conducted between oscillations in vertical and horizontal direction, between running shoes and between ground conditions (treadmill versus over ground running). Differences in the oscillation behavior could be detected between measurement directions with peak accelerations in the vertical being lower than those in the horizontal direction, p < 0.01. Peak accelerations occurred earlier at the distal accelerometer than at the proximal one, p < 0.01. Average normalized power differed between running shoes (p < 0.01) with harder damping material resulting in higher power values. Little to no power attenuation was found between the two accelerometers. Oscillation behavior of the Achilles tendon is not influenced by ground condition. Differences in shoe configurations may lead to variations in running technique and impact forces and therefore result in alterations of the vibration behavior at the Achilles tendon. The absence of power attenuation may have been caused by either a short distance between the two accelerometers or high stiffness of the tendon. High stiffness of the tendon will lead to complete transmission of the signal along the Achilles tendon and therefore no attenuation occurs.

Effect of Footwear Modifications on Oscillations at the Achilles Tendon during Running on a Treadmill and Over Ground: A Cross-Sectional Study

PubMed Central

Meinert, Ilka; Brown, Niklas; Alt, Wilfried

2016-01-01

Background Achilles tendon injuries are known to commonly occur in runners. During running repeated impacts are transferred in axial direction along the lower leg, therefore possibly affecting the oscillation behavior of the Achilles tendon. The purpose of the present study was to explore the effects of different footwear modifications and different ground conditions (over ground versus treadmill) on oscillations at the Achilles tendon. Methods Oscillations were measured in 20 male runners using two tri-axial accelerometers. Participants ran in three different shoe types on a treadmill and over ground. Data analysis was limited to stance phase and performed in time and frequency space. Statistical comparison was conducted between oscillations in vertical and horizontal direction, between running shoes and between ground conditions (treadmill versus over ground running). Results Differences in the oscillation behavior could be detected between measurement directions with peak accelerations in the vertical being lower than those in the horizontal direction, p < 0.01. Peak accelerations occurred earlier at the distal accelerometer than at the proximal one, p < 0.01. Average normalized power differed between running shoes (p < 0.01) with harder damping material resulting in higher power values. Little to no power attenuation was found between the two accelerometers. Oscillation behavior of the Achilles tendon is not influenced by ground condition. Conclusion Differences in shoe configurations may lead to variations in running technique and impact forces and therefore result in alterations of the vibration behavior at the Achilles tendon. The absence of power attenuation may have been caused by either a short distance between the two accelerometers or high stiffness of the tendon. High stiffness of the tendon will lead to complete transmission of the signal along the Achilles tendon and therefore no attenuation occurs. PMID:27010929

Attempting to realize n-type BiCuSeO

NASA Astrophysics Data System (ADS)

Zhang, Xiaoxuan; Feng, Dan; He, Jiaqing; Zhao, Li-Dong

2018-02-01

As an intrinsic p-type semiconductor, BiCuSeO has been widely researched in the thermoelectric community, however, n-type BiCuSeO has not been reported so far. In this work, we successfully realized n-type BiCuSeO through carrying out several successive efforts. Seebeck coefficient of BiCuSeO was increased through introducing extra Bi/Cu to fill the Bi/Cu vacancies that may produce holes, and the maximum Seebeck coefficient was increase from +447 μVK-1 for undoped BiCuSeO to +638 μVK-1 for Bi1.04Cu1.05SeO. The Seebeck coefficient of Bi1.04Cu1.05SeO was changed from p-type to n-type through electron doping through introducing Br/I in Se sites, the maximum negative Seebeck coefficient can reach ∼ -465 μVK-1 and -543 μVK-1 for Bi1.04Cu1.05Se1-xIxO and Bi1.04Cu1.05Se1-xBrxO, respectively. Then, after compositing Bi1.04Cu1.05Se0.99Br0.01O with Ag, n-type BiCuSeO can be absolutely obtained in the whole temperature range of 300-873 K, the maximum ZT 0.05 was achieved at 475 K in the Bi1.04Cu1.05Se0.99Br0.01O+15% Ag. Our report indicates that it is possible to realize n-type conducting behaviors in BiCuSeO system.

Ambipolar behavior and thermoelectric properties of WS2 nanotubes

NASA Astrophysics Data System (ADS)

Yomogida, Yohei; Kawai, Hideki; Sugahara, Mitsunari; Okada, Ryotaro; Yanagi, Kazuhiro

WS2 nanotubes are rolled multi-walled nanotubes made by a layered material, tungsten disulfides Since the discovery by Tenne et al in 1992, various physical properties have been revealed. Theoretical studies have suggested their distinct electronic properties from those of two dimensional sheet, such as one-dimensional electronic strucutures with sharp van Hove singularities and chiralitiy depended electronic structures. Their fibril structures enable us to make their random network films, however, the films are not conducting, and thus have not been used for electronic applications. Here we demonstrate that carrier injections on the WS2 networks by an electrolyte gating approach could make the networks as a semiconducting channel. We clarified the Raman characteristics of WS2 nanotubes networks under electrolyte gating, and confirmed capability of electron and hole injections. We revealed ambipolar behaviors of the WS2 nanotube networks in field effect transistor setups with electrolyte gating. In additio, we demosntrate N-type and P-type control of thermoelectric properties of WS2 nanotubes by electrolyte gating.The power factor of the WS2 nanotubes almost approached to that of the single crystalline WS2 flakes, suggesting good potential for thermoelectric applications..

The gram-negative sensing receptor PGRP-LC contributes to grooming induction in Drosophila

PubMed Central

Neyen, Claudine; Lemaitre, Bruno; Marion-Poll, Frédéric

2017-01-01

Behavioral resistance protects insects from microbial infection. However, signals inducing insect hygiene behavior are still relatively unexplored. Our previous study demonstrated that olfactory signals from microbes enhance insect hygiene behavior, and gustatory signals even induce the behavior. In this paper, we postulated a cross-talk between behavioral resistance and innate immunity. To examine this hypothesis, we employed a previously validated behavioral test to examine the function of taste signals in inducing a grooming reflex in decapitated flies. Microbes, which activate different pattern recognition systems upstream of immune pathways, were applied to see if there was any correlation between microbial perception and grooming reflex. To narrow down candidate elicitors, the grooming induction tests were conducted with highly purified bacterial components. Lastly, the role of DAP-type peptidoglycan in grooming induction was confirmed. Our results demonstrate that cleaning behavior can be triggered through recognition of DAP-type PGN by its receptor PGRP-LC. PMID:29121087

Relationship between polysomnographic sleep architecture and behavior in medication-free children with TS, ADHD, TS and ADHD, and controls.

PubMed

Stephens, Robyn J; Chung, Sharon A; Jovanovic, Dragana; Guerra, Randy; Stephens, Brandon; Sandor, Paul; Shapiro, Colin M

2013-01-01

To describe the relationship between sleep architecture and behavioral measures in unmedicated children and adolescents with Tourette syndrome (TS), attention-deficit hyperactivity disorder (ADHD), TS and comorbid ADHD (TS + ADHD), and healthy controls. The study also set out to examine differences in sleep architecture with each diagnosis. A cross-sectional, 2-night consecutive polysomnographic sleep study was conducted in 90 children. All participants were matched for age, gender, and level of intelligence. Scores on the Child Behavior Checklist delinquency measure were modestly but significantly correlated with the number of movements during REM sleep (r = .36, p = .003). Significant correlations were also noted among the number of total arousals and arousals from slow wave sleep (SWS), and scores on the measures of conduct disorder, hyperactivity/immaturity, and restless/disorganized behaviors. There were a few significant differences in sleep architecture among the diagnostic groups. The ADHD-only group exhibited a significantly higher number of total arousals (p < .01) and arousals from SWS (p < .01) compared with the other three study groups. Our findings indicate that children with TS and/or ADHD and who have more arousals from sleep are significantly more likely to have issues with conduct disorder, hyperactivity/immaturity, and restless/disorganized behavior. It was also noted that having ADHD, alone or comorbid with TS, is associated with a significantly greater number of movements during both non-REM and REM sleep. This study underscores the compelling need for the diagnosis and treatment of any sleep disorders in children with TS and/or ADHD so as to facilitate better management of problem behaviors.

Understanding breast cancer patients' preference for two types of exercise training during chemotherapy in an unblinded randomized controlled trial

PubMed Central

Courneya, Kerry S; Reid, Robert D; Friedenreich, Christine M; Gelmon, Karen; Proulx, Caroline; Vallance, Jeffrey K; McKenzie, Donald C; Segal, Roanne J

2008-01-01

Background Patient preference for group assignment may affect outcomes in unblinded trials but few studies have attempted to understand such preferences. The purpose of the present study was to examine factors associated with breast cancer patients' preference for two types of exercise training during chemotherapy. Methods Breast cancer patients (N = 242) completed a battery of tests including a questionnaire that assessed patient preference and the theory of planned behavior (TPB) prior to being randomized to usual care, resistance exercise training (RET), or aerobic exercise training (AET). Results 99 (40.9%) participants preferred RET, 88 (36.4%) preferred AET, and 55 (22.7%) reported no preference. Past exercisers (p = 0.023), smokers (p = 0.004), and aerobically fitter participants (p = 0.005) were more likely to prefer RET. As hypothesized, participants that preferred AET had more favorable TPB beliefs about AET whereas participants that preferred RET had more favorable TPB beliefs about RET. In multivariate modeling, patient preference for RET versus AET was explained (R2 = .46; p < 0.001) by the difference in motivation for RET versus AET (β = .56; p < 0.001), smoking status (β = .13; p = 0.007), and aerobic fitness (β = .12; p = 0.018). Motivational difference between RET versus AET, in turn, was explained (R2 = .48; p < 0.001) by differences in instrumental attitude (β = .27; p < 0.001), affective attitude (β = .25; p < 0.001), and perceived behavioral control (β = .24; p < 0.001). Conclusion Breast cancer patients' preference for RET versus AET during chemotherapy was predicted largely by a difference in motivation for each type of exercise which, in turn, was based on differences in their beliefs about the anticipated benefits, enjoyment, and difficulty of performing each type of exercise during chemotherapy. These findings may help explain patient preference effects in unblinded behavioral trials. Trial Registration ClinicalTrials.gov Identifier NCT00115713. PMID:18954442

[Characteristics of eating behavior in overweight young people with biliary tract diseases among Bashkortostan population].

PubMed

Volevach, L V; Khismatullina, G Ia; Uliamaeva, V V; Gur'ev, R D; Kamalova, A A

2014-01-01

The goal of the present research was to study the types of nutritional behavior disturbances in overweight patients with the pathology biliary tract. 132 patients with chronic noncalculous cholecystitis aged from 18 to 35 were examined. The comprehensive clinical examination was conducted and types of eating behavior disturbances with the help DEBQ test (Dutch Eating Behavior Questionnaire) were examined. It was discovered that disturbances of eating behavior are observed in 82,9 percent of normal weight patients, in 100 percent of overweight and in 93,3 percent of patients with obesity. Restraint and emotional eating are more often observed in obesity. External eating is more often observed in overweight and normal weight persons than that emotional eating. Rational eating is rarely observed in all groups of examined persons.

The effect of CO2 gas adsorption on the electrical properties of Fe doped TiO2 films

NASA Astrophysics Data System (ADS)

Mardare, Diana; Adomnitei, Catalin; Florea, Daniel; Luca, Dumitru; Yildiz, Abdullah

2017-11-01

CO2 has to be monitored for indoor air quality, being also an important greenhouse gas. The electrical and sensing gas properties of the undoped and Fe doped TiO2 thin films, obtained by RF sputtering, have been investigated in different CO2 atmospheres. It was observed that the response to CO2 increases by Fe doping for the lowest doped film, and then decreases, as the dopant concentration increases. An explanation was given based on multiphonon-assisted hopping model. By studying the films electrical conductivity in front of a certain CO2 atmosphere, we have qualitatively evidenced the semiconducting n-type nature of the films under study, except for the highest Fe doped film which has a p-type behavior. An important finding is that Fe doping determines the decrease of the optimum operating temperature, approaching the room temperature.

Electrically active point defects in Mg implanted n-type GaN grown by metal-organic chemical vapor deposition

NASA Astrophysics Data System (ADS)

Alfieri, G.; Sundaramoorthy, V. K.; Micheletto, R.

2018-05-01

Magnesium (Mg) is the p-type doping of choice for GaN, and selective area doping by ion implantation is a routine technique employed during device processing. While electrically active defects have been thoroughly studied in as-grown GaN, not much is known about defects generated by ion implantation. This is especially true for the case of Mg. In this study, we carried out an electrical characterization investigation of point defects generated by Mg implantation in GaN. We have found at least nine electrically active levels in the 0.2-1.2 eV energy range, below the conduction band. The isochronal annealing behavior of these levels showed that most of them are thermally stable up to 1000 °C. The nature of the detected defects is then discussed in the light of the results found in the literature.

Microdistribution of oxygen in silicon

NASA Technical Reports Server (NTRS)

Murgai, A.; Chi, J. Y.; Gatos, H. C.

1980-01-01

The microdistribution of oxygen in Czochralskii-grown, p-type silicon crystals was determined by using the SEM in the EBIC mode in conjunction with spreading resistance measurements. When the conductivity remained p-type, bands of contrast were observed in the EBIC image which corresponded to maxima in resistivity. When at the oxygen concentration maxima the oxygen donor concentration exceeded the p-type dopant concentration, an inversion of the conductivity occurred. It resulted in the formation of p-n junctions in a striated configuration and the local inversion of the EBIC image contrast. By heat-treating silicon at 1000 C prior to the activation of oxygen donors, some silicon-oxygen micro-precipitates were observed in the EBIC image within the striated oxygen concentration maxima.

Semiconductor-to-metal transition in rutile TiO 2 induced by tensile strain

DOE PAGES

Benson, Eric E.; Miller, Elisa M.; Nanayakkara, Sanjini U.; ...

2017-02-10

Here, we report the first observation of a reversible, degenerate doping of titanium dioxide with strain, which is referred to as a semiconductor-to-metal transition. Application of tensile strain to a ~50 nm film of rutile TiO 2 thermally grown on a superelastic nitinol (NiTi intermetallic) substrate causes reversible degenerate doping as evidenced by electrochemistry, X-ray photoelectron spectroscopy (XPS), and conducting atomic force microscopy (CAFM). Cyclic voltammetry and impedance measurements show behavior characteristic of a highly doped n-type semiconductor for unstrained TiO 2 transitioning to metallic behavior under tensile strain. The transition reverses when strain is removed. Valence band XPS spectramore » show that samples strained to 5% exhibit metallic-like intensity near the Fermi level. Strain also induces a distinct transition in CAFM current-voltage curves from rectifying (typical of an n-type semiconductor) to ohmic (metal-like) behavior. We propose that strain raises the energy distribution of oxygen vacancies ( n-type dopants) near the conduction band and causes an increase in carrier concentration. As the carrier concentration is increased, the width of the depletion region is reduced, which then permits electron tunneling through the space charge barrier resulting in the observed metallic behavior.« less

Using the Clear Communication Index to Improve Materials for a Behavioral Intervention.

PubMed

Porter, Kathleen J; Alexander, Ramine; Perzynski, Katelynn M; Kruzliakova, Natalie; Zoellner, Jamie M

2018-02-08

Ensuring that written materials used in behavioral interventions are clear is important to support behavior change. This study used the Clear Communication Index (CCI) to assess the original and revised versions of three types of written participant materials from the SIPsmartER intervention. Materials were revised based on original scoring. Scores for the entire index were significantly higher among revised versions than originals (57% versus 41%, p < 0.001); however, few revised materials (n = 2 of 53) achieved the benchmark of ≥90%. Handouts scored higher than worksheets and slide sets for both versions. The proportion of materials scored as having "a single main message" significantly increased between versions for worksheets (7% to 57%, p = 0.003) and slide sets (33% to 67%, p = 0.004). Across individual items, most significant improvements were in Core, with four-items related to the material having a single main message. Findings demonstrate that SIPsmartER's revised materials improved after CCI-informed edits. They advance the evidence and application of the CCI, suggesting it can be effectively used to support improvement in clarity of different types of written materials used in behavioral interventions. Implications for practical considerations of using the tool and suggestions for modifications for specific types of materials are presented.

Differences in substance-related risk behavior between dual and triple diagnosed severely mentally ill adults.

PubMed

Hampton, Michelle Decoux; Chafetz, Linda; Portillo, Carmen

2012-02-01

OBJECTIVES: The purpose of this study was to determine if differences exist between adults with dual and triple diagnoses with regard to substance-related risk behaviors. METHODS: This secondary analysis was a cross-sectional study. There were 252 subjects with dual and triple diagnoses recruited from residential crisis programs in San Francisco. Using descriptive and logistic regression analyses, subjects in the two groups were compared with regard to demographic data, types of substances, and routes of administration used in the previous 30 days to determine risk for exposure and/or transmission of HIV/HCV. RESULTS: When compared to the dual diagnosis group, subjects with triple diagnoses were four times more likely to have engaged in IDU (p=.001) and 2.6 times more likely to use amphetamines (p=.05). They also reported using more types of substances over the lifetime (p<.0001). But with regard to other risk behaviors such as alcohol use to intoxication and cocaine/crack use, there were no significant differences. CONCLUSION: Though many substance-related risk behaviors occurred in both groups, adults with triple diagnoses were more likely to engage in IDU, amphetamine use, and to use more types of substances over the lifetime. This information has the potential to inform interventions that might prevent/reduce substance-related risk in this population.

Assessing fear of hypoglycemia in a population-based study among parents of children with type 1 diabetes - psychometric properties of the hypoglycemia fear survey - parent version.

PubMed

Haugstvedt, Anne; Wentzel-Larsen, Tore; Aarflot, Morten; Rokne, Berit; Graue, Marit

2015-01-19

In the treatment of childhood type 1 diabetes, being aware of the parents' fear of hypoglycemia is important, since the parents' fear may influence the management of treatment and the children's blood glucose regulation. The availability of proper instruments to assess the parents' fear of hypoglycemia is essential. Thus, the aim of this study was to examine the psychometric properties of the Hypoglycemia Fear Survey - Parent version (HFS-P). In a Norwegian population-based sample, 176 parents representing 102 children with type 1 diabetes (6-15 years old) completed the HFS-P, comprising a 15-item worry subscale and a 10-item behavior subscale. We performed exploratory and confirmatory factor analysis and further analysis of the scales' construct validity, content validity and reliability. The Norwegian version of the HFS-P had an acceptable factor structure and internal consistency for the worry subscale, whereas the structure and internal consistency of the behavior subscale was more questionable. The HFS-P subscales were significantly correlated (from moderately to weakly) with symptoms of emotional distress, as measured by the Hopkins Symptom Checklist - 25 items. The mothers scored higher than fathers on both HFS-P subscales, but the difference was not statistically significant for the worry subscale. The HFS-P worry subscale seems to be a valid scale for measuring anxiety-provoking aspects of hypoglycemia, and the validity of the HFS-P behavior subscale needs to be investigated further.

Type D personality is associated with impaired psychological status and unhealthy lifestyle in Icelandic cardiac patients: a cross-sectional study.

PubMed

Svansdottir, Erla; van den Broek, Krista C; Karlsson, Hrobjartur D; Gudnason, Thorarinn; Denollet, Johan

2012-01-18

Type D (distressed) personality has been associated with adverse cardiac prognosis and poor emotional well-being in cardiac patients, but it is still unclear what mechanisms link Type D personality with poor clinical outcomes in cardiac patients. In the present cohort of Icelandic cardiac patients, we examined potential pathways that may explain this relationship. The objectives were to examine 1) the association between Type D personality and impaired psychological status, and to explore whether this association is independent of disease severity; and 2) the association between Type D personality and an unhealthy lifestyle. A sample of 268 Icelandic coronary angiography patients (74% males (N = 199); mean age 62.9 years (SD 10.5), range 28-85 years) completed the Type D Scale (DS14), Hospital Anxiety and Depression Scale (HADS), and Perceived Stress Scale (PSS) at hospitalization. Health-related behaviors were assessed 4 months following angiography. Clinical data were collected from medical files. Type D personality was associated with an increased risk of anxiety (OR 2.97, 95% CI:1.55-5.69), depression (OR 4.01, 95% CI:1.42-11.29), and stress (OR 5.99, 95% CI:3.08-11.63), independent of demographic variables and disease severity. Furthermore, fish consumption was lower among Type Ds, as 21% of Type Ds versus 5% of non-Type Ds consumed fish < 1 a week (p < 0.001). Type D patients were also more likely to smoke at follow-up (22% versus 10%, p = 0.024) and to use antidepressants (17% versus 9%, p = 0.049) and sleeping pills (49% versus 33%, p = 0.019) compared to non-Type Ds. Type D personality was not associated with other health-related behaviors, aside from trends towards less fruit and vegetable consumption, and more weight gain. Type D personality was associated with psychological distress and an unhealthy lifestyle in Icelandic cardiac patients. Future studies should further investigate the association between Type D personality and health-related behaviors.

p-Type Transparent Conducting Oxide/n-Type Semiconductor Heterojunctions for Efficient and Stable Solar Water Oxidation.

PubMed

Chen, Le; Yang, Jinhui; Klaus, Shannon; Lee, Lyman J; Woods-Robinson, Rachel; Ma, Jie; Lum, Yanwei; Cooper, Jason K; Toma, Francesca M; Wang, Lin-Wang; Sharp, Ian D; Bell, Alexis T; Ager, Joel W

2015-08-05

Achieving stable operation of photoanodes used as components of solar water splitting devices is critical to realizing the promise of this renewable energy technology. It is shown that p-type transparent conducting oxides (p-TCOs) can function both as a selective hole contact and corrosion protection layer for photoanodes used in light-driven water oxidation. Using NiCo2O4 as the p-TCO and n-type Si as a prototypical light absorber, a rectifying heterojunction capable of light driven water oxidation was created. By placing the charge separating junction in the Si using a np(+) structure and by incorporating a highly active heterogeneous Ni-Fe oxygen evolution catalyst, efficient light-driven water oxidation can be achieved. In this structure, oxygen evolution under AM1.5G illumination occurs at 0.95 V vs RHE, and the current density at the reversible potential for water oxidation (1.23 V vs RHE) is >25 mA cm(-2). Stable operation was confirmed by observing a constant current density over 72 h and by sensitive measurements of corrosion products in the electrolyte. In situ Raman spectroscopy was employed to investigate structural transformation of NiCo2O4 during electrochemical oxidation. The interface between the light absorber and p-TCO is crucial to produce selective hole conduction to the surface under illumination. For example, annealing to produce more crystalline NiCo2O4 produces only small changes in its hole conductivity, while a thicker SiOx layer is formed at the n-Si/p-NiCo2O4 interface, greatly reducing the PEC performance. The generality of the p-TCO protection approach is demonstrated by multihour, stable, water oxidation with n-InP/p-NiCo2O4 heterojunction photoanodes.

U.S. adult cigar smoking patterns, purchasing behaviors, and reasons for use according to cigar type: Findings from the Population Assessment of Tobacco and Health (PATH) Study, 2013-14.

PubMed

Corey, Catherine G; Holder-Hayes, Enver; Nguyen, Anh B; Delnevo, Cristine D; Rostron, Brian L; Bansal-Travers, Maansi; Kimmel, Heather L; Koblitz, Amber; Lambert, Elizabeth; Pearson, Jennifer L; Sharma, Eva; Tworek, Cindy; Hyland, Andrew J; Conway, Kevin P; Ambrose, Bridget K; Borek, Nicolette

2017-09-15

The U.S. cigar market is diverse, yet until recently most research studies and tobacco surveillance systems have not reported behavioral and related outcomes by cigar type. The 2013-14 Population Assessment of Tobacco and Health Study collected data separately for filtered cigars (FCs), cigarillos and traditional cigars, which were further distinguished as premium or non-premium. Descriptive statistics for adult established current smokers of each cigar type and cigarettes were calculated for demographic characteristics, tobacco use patterns, purchasing behaviors and reasons for use. Adjusted prevalence ratios (APRs) using a marginal predictions approach with logistic regression assessed correlates of dual cigar and cigarette smoking. Age, sex, race/ethnicity, education level and poverty status of smokers varied according to cigar type. Daily cigar smoking prevalence and number of cigars smoked per day were higher for FCs (37.3%; median: 1.6 cigars/day, respectively), than all other cigar types (6.7%-25.3%, all p<0.01; 0.1-0.4 cigars/day, all p<0.01, respectively); daily smoking and cigars per day were similar for non-premium cigars and cigarillos (p=0.11; p=0.33, respectively). Cigarette smoking was twice as common among smokers of non-premium cigars, cigarillos, and FCs (58.0%-66.0%) than among premium cigars (29.9%). Among current cigar smokers, FC smokers (APR=1.23, 95%CI=1.09-1.39), other tobacco product users (APR=1.27, 95%CI=1.15-1.41), and those with a GED/high school diploma or less (APR=1.20, 95%CI=1.09-1.33) were more likely to also smoke cigarettes. User characteristics, cigar smoking patterns, and dual smoking with cigarettes varied by cigar type highlighting the importance of adequately describing the cigar type studied and, where appropriate, differentiating results by cigar type. Despite the diversity of the cigar market place, historically many research studies and tobacco surveillance systems have treated cigars as a single product type. This study describes similarities and differences in the user characteristics, tobacco use patterns, and purchasing behaviors of premium, non-premium, cigarillo and filtered cigar smokers. To enhance tobacco regulatory science, sufficient descriptions of the cigar type(s) studied and, where appropriate, differentiation of the particular cigar type(s) studied should be undertaken to improve the interpretation of study findings, understanding of cigar use patterns and related behaviors and future approaches to reducing cigar-attributable morbidity and mortality. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Practical Considerations of Excluding Conduct Disordered Students: An Empirical Analysis.

ERIC Educational Resources Information Center

Pullis, Michael

1991-01-01

Ratings of 224 students with serious emotional disturbances by 40 teachers indicated that conduct disorders were very prevalent, were correlated with other problematic aspects of temperament and classroom competence, and co-occurred with other types of behavioral problems. Implications of the study for making eligibility decisions for special…

Increased p-type conductivity through use of an indium surfactant in the growth of Mg-doped GaN

NASA Astrophysics Data System (ADS)

Kyle, Erin C. H.; Kaun, Stephen W.; Young, Erin C.; Speck, James S.

2015-06-01

We have examined the effect of an indium surfactant on the growth of p-type GaN by ammonia-based molecular beam epitaxy. p-type GaN was grown at temperatures ranging from 700 to 780 °C with and without an indium surfactant. The Mg concentration in all films in this study was 4.5-6 × 1019 cm-3 as measured by secondary ion mass spectroscopy. All p-type GaN films grown with an indium surfactant had higher p-type conductivities and higher hole concentrations than similar films grown without an indium surfactant. The lowest p-type GaN room temperature resistivity was 0.59 Ω-cm, and the highest room temperature carrier concentration was 1.6 × 1018 cm-3. Fits of the temperature-dependent carrier concentration data showed a one to two order of magnitude lower unintentional compensating defect concentration in samples grown with the indium surfactant. Samples grown at higher temperature had a lower active acceptor concentration. Improvements in band-edge luminescence were seen by cathodoluminescence for samples grown with the indium surfactant, confirming the trends seen in the Hall data.

Associations between Physical Activity and Reduced Rates of Hopelessness, Depression, and Suicidal Behavior among College Students

ERIC Educational Resources Information Center

Taliaferro, Lindsay A.; Rienzo, Barbara A.; Pigg, R. Morgan; Miller, M. David; Dodd, Virginia J.

2009-01-01

Objective: The authors explored associations among types of physical activity and hopelessness, depression, and suicidal behavior among college students. Participants: Participants included 43,499 college students aged 18 to 25 who completed the 2005 National College Health Assessment conducted by the American College Health Association. Methods:…

Pilot randomized controlled trial of a mindfulness-based group intervention in adolescent girls at risk for type 2 diabetes with depressive symptoms.

PubMed

Shomaker, Lauren B; Bruggink, Stephanie; Pivarunas, Bernadette; Skoranski, Amanda; Foss, Jillian; Chaffin, Ella; Dalager, Stephanie; Annameier, Shelly; Quaglia, Jordan; Brown, Kirk Warren; Broderick, Patricia; Bell, Christopher

2017-06-01

(1) Evaluate feasibility and acceptability of a mindfulness-based group in adolescent girls at-risk for type 2 diabetes (T2D) with depressive symptoms, and (2) compare efficacy of a mindfulness-based versus cognitive-behavioral group for decreasing depressive symptoms and improving insulin resistance. Parallel-group, randomized controlled pilot trial conducted at a university. Thirty-three girls 12-17y with overweight/obesity, family history of diabetes, and elevated depressive symptoms were randomized to a six-week mindfulness-based (n=17) or cognitive-behavioral program (n=16). Both interventions included six, one-hour weekly group sessions. The mindfulness-based program included guided mindfulness awareness practices. The cognitive-behavioral program involved cognitive restructuring and behavioral activation. Adolescents were evaluated at baseline, post-intervention, and six-months. Feasibility/acceptability were measured by attendance and program ratings. Depressive symptoms were assessed by validated survey. Insulin resistance was determined from fasting insulin and glucose, and dual energy x-ray absorptiometry was used to assess body composition. Most adolescents attended ≥80% sessions (mindfulness: 92% versus cognitive-behavioral: 87%, p=1.00). Acceptability ratings were strong. At post-treatment and six-months, adolescents in the mindfulness condition had greater decreases in depressive symptoms than adolescents in the cognitive-behavioral condition (ps<.05). Compared to the cognitive-behavioral condition, adolescents in the mindfulness-based intervention also had greater decreases in insulin resistance and fasting insulin at post-treatment, adjusting for fat mass and other covariates (ps<.05). A mindfulness-based intervention shows feasibility and acceptability in girls at-risk for T2D with depressive symptoms. Compared to a cognitive-behavioral program, after the intervention, adolescents who received mindfulness showed greater reductions in depressive symptoms and better insulin resistance. ClinicalTrials.gov identifier: NCT02218138 clinicaltrials.gov. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pilot Randomized Controlled Trial of a Mindfulness-Based Group Intervention in Adolescent Girls at Risk for Type 2 Diabetes with Depressive Symptoms

PubMed Central

Shomaker, Lauren B.; Bruggink, Stephanie; Pivarunas, Bernadette; Skoranski, Amanda; Foss, Jillian; Chaffin, Ella; Dalager, Stephanie; Annameier, Shelly; Quaglia, Jordan; Brown, Kirk Warren; Broderick, Patricia; Bell, Christopher

2017-01-01

Objective (1) Evaluate feasibility and acceptability of a mindfulness-based group in adolescent girls at-risk for type 2 diabetes (T2D) with depressive symptoms, and (2) compare efficacy of a mindfulness-based versus cognitive-behavioral group for decreasing depressive symptoms and improving insulin resistance. Design and setting Parallel-group, randomized controlled pilot trial conducted at a university. Participants Thirty-three girls 12-17y with overweight/obesity, family history of diabetes, and elevated depressive symptoms were randomized to a six-week mindfulness-based (n=17) or cognitive-behavioral program (n=16). Interventions Both interventions included six, one-hour weekly group sessions. The mindfulness-based program included guided mindfulness awareness practices. The cognitive-behavioral program involved cognitive restructuring and behavioral activation. Main outcome measures Adolescents were evaluated at baseline, post-intervention, and six-months. Feasibility/acceptability were measured by attendance and program ratings. Depressive symptoms were assessed by validated survey. Insulin resistance was determined from fasting insulin and glucose, and dual energy x-ray absorptiometry was used to assess body composition. Results Most adolescents attended ≥80% sessions (mindfulness:92% versus cognitive-behavioral:87%, p=1.00). Acceptability ratings were strong. At post-treatment and six-months, adolescents in the mindfulness condition had greater decreases in depressive symptoms than adolescents in the cognitive-behavioral condition (ps<.05). Compared to the cognitive-behavioral condition, adolescents in the mindfulness-based intervention also had greater decreases in insulin resistance and fasting insulin at post-treatment, adjusting for fat mass and other covariates (ps<.05). Conclusions A mindfulness-based intervention shows feasibility and acceptability in girls at-risk for T2D with depressive symptoms. Compared to a cognitive-behavioral program, after the intervention, adolescents who received mindfulness showed greater reductions in depressive symptoms and better insulin resistance. PMID:28619307

Effects of P3HT concentration on the electrical properties of the Au/PEDOT:PSS/P3HT/n-GaN hybrid junction structure

NASA Astrophysics Data System (ADS)

Noh, Ji-yeon; Lee, Ha Young; Lim, Kyung-won; Ahn, Hyung Soo; Yi, Sam Nyung; Jeon, Hunsoo; Shin, Min Jeong; Yu, Young Moon; Ha, Dong Han

2017-09-01

An inorganic-organic hybrid junction has been fabricated by spin coating the p-type poly(3- hexylthiophene-2,5-diyl)(P3HT) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT: PSS) on an n-type GaN layer. The GaN layer was formed on Al2O3 by metal organic chemical vapor deposition(MOCVD) method. To investigate the effects of P3HT concentration on the electrical properties, we changed P3HT solution concentration and speed of spin coater. The currentvoltage (I-V ) characteristic of Au/PEDOT:PSS/P3HT/n-GaN shows rectifying behavior. The I-V characteristic was examined in the frame work of the thermionic emission model. The most proper rectifying behavior was obtained for 0.6 wt% and thickness below 65 nm of P3HT used diode. We expect that such hybrid structures, suitably developed, might be enable the fabrication of highquality electronic and optoelectronic devices.

Driver Behavioral Changes through Interactions with an Automatic Brake System for Collision Avoidance

NASA Astrophysics Data System (ADS)

Itoh, Makoto; Fujiwara, Yusuke; Inagaki, Toshiyuki

This paper discusses driver's behavioral changes as a result of driver's use of an automatic brake system for preventing a rear-end collision from occurring. Three types of automatic brake systems are investigated in this study. Type 1 brake system applies a strong automatic brake when a collision is very imminent. Type 2 brake system initiates brake operation softly when a rear-end crash may be anticipated. Types 1 and 2 are for avoidance of a collision. Type 3 brake system, on the other hand, applies a strong automatic brake to reduce the damage when a collision can not be avoided. An experiment was conducted with a driving simulator in order to analyze the driver's possible behavioral changes. The results showed that the time headway (THW) during car following phase was reduced by use of an automatic brake system of any type. The inverse of time to collision (TTC), which is an index of the driver's brake timing, increased by use of Type 1 brake system when the deceleration rate of the lead vehicle was relatively low. However, the brake timing did not change when the drivers used Type 2 or 3 brake system. As a whole, dangerous behavioral changes, such as overreliance on a brake system, were not observed for either type of brake system.

Dielectric relaxation and ac conductivity behavior of carboxyl functionalized multiwalled carbon nanotubes/poly (vinyl alcohol) composites

NASA Astrophysics Data System (ADS)

Amrin, Sayed; Deshpande, V. D.

2017-03-01

We study the dielectric relaxation and ac conductivity behavior of MWCNT-COOH/Polyvinyl alcohol nanocomposite films in the temperature (T) range 303-423 K and in the frequency (f) range 0.1 Hz-1 MHz. The dielectric constant increases with an increase in temperature and also with an increase in MWCNT-COOH loading into the polymer matrix, as a result of interfacial polarization. The permittivity data were found to fit well with the modified Cole-Cole equation. Temperature dependent values of the relaxation times, free charge carrier conductivity and space charge carrier conductivity were extracted from the equation. An observed increment in the ac conductivity for the nanocomposites was analysed by a Jonscher power law which suggests that the correlated barrier hopping is the dominant charge transport mechanism for the nanocomposite films. The electric modulus study revealed deviations from ideal Debye-type behavior which are explained by considering a generalized susceptibility function. XRD and DSC results show an increase in the degree of crystallinity.

P-type conductivity in annealed strontium titanate

DOE PAGES

Poole, Violet M.; Corolewski, Caleb D.; McCluskey, Matthew D.

2015-12-17

In this study, Hall-effect measurements indicate p-type conductivity in bulk, single-crystal strontium titanate (SrTiO 3, or STO) samples that were annealed at 1200°C. Room temperature mobilities above 100 cm 2/Vs were measured, an order of magnitude higher than those for electrons (5-10 cm 2/Vs). Average hole densities were in the 10 9-10 10 cm -3 range, consistent with a deep acceptor.

Chemical Vapor Deposition Growth of Degenerate p-Type Mo-Doped ReS2 Films and Their Homojunction.

PubMed

Qin, Jing-Kai; Shao, Wen-Zhu; Xu, Cheng-Yan; Li, Yang; Ren, Dan-Dan; Song, Xiao-Guo; Zhen, Liang

2017-05-10

Substitutional doping of transition metal dichalcogenide two-dimensional materials has proven to be effective in tuning their intrinsic properties, such as band gap, transport characteristics, and magnetism. In this study, we realized substitutional doping of monolayer rhenium disulfide (ReS 2 ) with Mo via chemical vapor deposition. Scanning transmission electron microscopy demonstrated that Mo atoms are successfully doped into ReS 2 by substitutionally replacing Re atoms in the lattice. Electrical measurements revealed the degenerate p-type semiconductor behavior of Mo-doped ReS 2 field effect transistors, in agreement with density functional theory calculations. The p-n diode device based on a doped ReS 2 and ReS 2 homojunction exhibited gate-tunable current rectification behaviors, and the maximum rectification ratio could reach up to 150 at V d = -2/+2 V. The successful synthesis of p-type ReS 2 in this study could largely promote its application in novel electronic and optoelectronic devices.

Physician communication behaviors from the perspective of adult HIV patients in Kenya.

PubMed

Wachira, Juddy; Middlestadt, Susan; Reece, Michael; Peng, Chao-Ying Joanne; Braitstein, Paula

2014-04-01

We describe perceived physician communication behaviors and its association with adherence to care, among HIV patients in Kenya. This cross-sectional study was conducted between July and August 2011. The study was conducted in three adult HIV clinics within the Academic Model Providing Healthcare program in western Kenya. HIV adult patients. Patient's predisposition to attend clinic, missed appointment and missed combined antiretroviral therapy (cART) medication. A total of 400 patients were enrolled and participated in the study; the median age was 38 years (IQR = 33-44) and 56.5% were female. Patients perceived physicians engaged in a high number of communication behaviors (mean = 3.80, range 1-5). A higher perceived general health status (P = 0.01), shorter distance to the health facility (P = 0.03) and lesser time spent at the health facility (P = 0.02) were associated with a higher number of perceived physician communication behaviors. Physician-patient relationship factors were not associated with physician communication behaviors. In addition, a higher number of perceived physician communication behaviors was associated with a very high likelihood of patients' attending the next HIV clinic [adjusted odds ratio (AOR): 1.89, 95% confidence interval (CI): 1.49-2.40], a lower likelihood of patients' missing an appointment (AOR: 0.75, 95% CI: 0.61-0.92) and missing cART medication (AOR: 0.68, 95% CI: 0.52-0.87). Patients' perception of physician communication behaviors was found to be associated with their adherence to HIV care.

Delamination Behavior of L-Shaped Laminated Composites

NASA Astrophysics Data System (ADS)

Geleta, Tsinuel N.; Woo, Kyeongsik; Lee, Bongho

2018-05-01

We studied the delamination behavior of L-shaped laminated composites numerically and experimentally. In finite-element modeling, cohesive zone modeling was used to simulate the delamination of plies. Cohesive elements were inserted between bulk elements at each interlayer to represent the occurrence of multiple delaminations. The laminated composite models were subjected to several types of loading inducing opening and shearing types of delamination. Numerical results were compared to those in the literature and of experiments conducted in this study. The results were carefully examined to investigate diverse delamination initiation and propagation behaviors. The effect of varying presence and location of pre-crack was also studied.

Relationships Among Perceived Wellness Culture, Healthy Lifestyle Beliefs, and Healthy Behaviors in University Faculty and Staff: Implications for Practice and Future Research.

PubMed

Melnyk, Bernadette Mazurek; Amaya, Megan; Szalacha, Laura A; Hoying, Jacqueline

2016-03-01

Identifying key factors influencing healthy lifestyle behaviors in university faculty and staff is critical in designing interventions to improve health outcomes and reduce health care costs. A descriptive study was conducted with 3,959 faculty and staff at a Midwestern, U.S. University. Key measures included perceived worksite culture, healthy lifestyle beliefs, and healthy lifestyle behaviors. Healthy lifestyle beliefs were strongly positively associated with healthy lifestyle behaviors. Regression analyses demonstrated positive healthy lifestyle behaviors based upon sex (female, Std. β = .068, p < .001) and role (faculty, Std. β = .059, p < .001) and a negative effect of race (African Americans, Std. β = -.059, p < .001). The positive effect of perceived wellness culture on healthy lifestyle behaviors was completely mediated by healthy lifestyle beliefs. Interventions to enhance perceived wellness culture and healthy lifestyle beliefs should result in healthier behaviors and improved health outcomes. © The Author(s) 2015.

In situ monitoring of stacking fault formation and its carrier lifetime mediation in p-type 4H-SiC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Bin, E-mail: chenbinmse@gmail.com; Chen, Jun; Yao, Yuanzhao

Using the fine control of an electron beam (e-beam) in scanning electron microscopy with the capabilities of both electrical and optical imaging, the stacking fault (SF) formation together with its tuning of carrier lifetime was in situ monitored and investigated in p-type 4H-SiC homoepitaxial films. The SFs were formed through engineering basal plane dislocations with the energy supplied by the e-beam. The e-beam intensity required for the SF formation in the p-type films was ∼100 times higher than that in the n-type ones. The SFs reduced the minority-carrier lifetime in the p-type films, which was opposite to that observed inmore » the n-type case. The reason for the peculiar SF behavior in the p-type 4H-SiC is discussed with the cathodoluminescence results.« less

Organic/Inorganic Hybrid p-n Junction with PEDOT Nanoparticles for Light-Emitting Diode

NASA Astrophysics Data System (ADS)

Kim, M. S.; Jin, S. M.; Cho, M. Y.; Choi, H. Y.; Kim, G. S.; Jeon, S. M.; Yim, K. G.; Kim, H. G.; Shim, K. B.; Kang, B. K.; Kim, Y.; Lee, D. Y.; Kim, J. S.; Kim, J. S.; Leem, J. Y.

2011-12-01

A heavily Si-doped GaN/polymer hybrid structure with p-type poly(3,4-ethylene-dioxythiophene):beta-1,3-glucan (PEDOT nanoparticle) interface layer has been fabricated. The Si-doped GaN thin film with carrier concentration of 1×1019 cm-3 was grown by metal-organic chemical vapor deposition (MOCVD). The PEDOT nanoparticle with various sizes ranging from 60 to 120 nm was synthesized via a miniemulsion polymerization process. The electrical conductivity of the PEDOT nanoparticle is less than 1.2 S/cm. The current-voltage (I-V) characteristic of the hybrid structure shows diode-like behavior. The I-V characteristic was examined in the framework of the thermionic emission model. The ideality factor and barrier height of the hybrid structure were obtained as 5.6 and 0.41 eV, respectively. The value of ideality factor is decreased by inserting the PEDOT nanoparticle interface layer.

Academic Goals and Self-Handicapping Strategies in University Students.

PubMed

Ferradás, María del Mar; Freire, Carlos; Valle, Antonio; Núñez, José Carlos

2016-05-23

In highly competitive settings like university, the fear of failure leads some students to protect their self-worth using self-handicapping strategies. The present investigation examines to what extent academic goals are related to those tactics in university students. Specifically, MANCOVA was applied to estimate statistical differences linked to behavioral and claimed self-handicapping strategies according to the level (high/medium/low) of four types of academic goal (achievement approach, achievement avoidance, mastery approach, and work avoidance). Degree, year in school, and gender were entered as covariates. 940 students (86.5% women) from University of A Coruña (M = 20.44; SD = 1.73) participated. Results show that: (a) both behavioral and claimed self-handicapping are promoted by ego-oriented goals (achievement avoidance, F(2, 937) = 23.56, p < .001, η p 2 = .048; achievement approach, F(2, 937) = 7.49, p < .001, η p 2 = .016); (b) work avoidance goals are related to behavioral self-handicapping (F(2, 937) = 9.09, p < .001, η p 2 = .019), but are not statistically linked to claimed self-handicapping; and (c) mastery approach goals are significantly, negatively related to both types of self-handicapping (F(2, 937) = 20.09, p < .001, η p 2 = .041). Psychological and educational implications of the findings are discussed.

Comparison of lifestyles of young women with and without primary dysmenorrhea

PubMed Central

Bavil, Dina Abadi; Dolatian, Mahrokh; Mahmoodi, Zohreh; Baghban, Alireza Akbarzadeh

2016-01-01

Introduction Dysmenorrhea is one of the most common gynecologic disorders that affects women’s quality of life and social activities. Lifestyle, eating behaviors, and general health are essential to the management of menstrual symptoms. This study was conducted to examine the relationship between lifestyle and primary dysmenorrhea in students at Sari University of Medical Sciences in 2015 in order to facilitate the performance of lifestyle-improving interventions among young women. Methods This study was conducted on 250 students with and without primary dysmenorrhea at Sari University of Medical Sciences in 2015. Data were collected using personal-social and lifestyle questionnaires (addressing nutrition, physical activity, stress, social relationships, improper health behaviors, and self-care). The data were analyzed by SPSS software, version 18, using the independent-samples t-test, the chi-squared test, and logistic regression analysis. Results Given the scores obtained on the lifestyle questionnaire, significant differences were observed between the groups with and without dysmenorrhea in terms of eating behavior (p=0.008), physical activity (p=0.011), stress (p=0.041), and social relationships (p=0.000). No differences were observed in terms of self-care (p=0.115) and smoking, drinking, and drug use (p=0.355). According to the logistic regression analysis, age (OR=1.208, p=0.014), physical activity (OR=1.008, p=0.040) and social relationship (OR=0.952, p=0.002) were different in the two groups, but there was no statistical differences in their eating behavior, self-care, and stress. Conclusion To prevent and reduce the incidence of primary dysmenorrhea, knowledge and awareness should be raised in young women through proper lifestyle education and health promotion measures. PMID:27123219

The association between demographic and behavioral characteristics and sunburn among U.S. adults - National Health Interview Survey, 2010.

PubMed

Holman, Dawn M; Berkowitz, Zahava; Guy, Gery P; Hartman, Anne M; Perna, Frank M

2014-06-01

To examine the association between demographic and behavioral characteristics and sunburn among U.S. adults. We used 2010 National Health Interview Survey data (N=24,970) to conduct multivariable logistic regressions examining associations with having 1 or more sunburns in the past year and having 4 or more sunburns in the past year. Overall, 37.1% of adults experienced sunburn in the past year. The adjusted prevalence of sunburn was particularly common among adults aged 18-29years (52.0%), those who repeatedly burn or freckle after 2weeks in the sun (45.9%), whites (44.3%), indoor tanners (44.1%), those with a family history of melanoma (43.9%), and those who are US-born (39.5%). Physical activity, alcohol consumption, and overweight/obesity were positively associated with sunburn (all P<0.001); sun protection behaviors were not significantly associated with sunburn (P=0.35). Among those who were sunburned in the past year, 12.1% experienced 4 or more sunburns. Sunburn is common, particularly among younger adults, those with a more sun-sensitive skin type, whites, those with a family history of melanoma, the highly physically active, and indoor tanners. Efforts are needed to facilitate sun-safety during outdoor recreation, improve the consistency of sun protection practices, and prevent sunburn, particularly among these subgroups. Published by Elsevier Inc.

The association between demographic and behavioral characteristics and sunburn among U.S. adults — National Health Interview Survey, 2010⋆

PubMed Central

Holman, Dawn M.; Berkowitz, Zahava; Guy, Gery P.; Hartman, Anne M.; Perna, Frank M.

2015-01-01

Objective To examine the association between demographic and behavioral characteristics and sunburn among U.S. adults. Method We used 2010 National Health Interview Survey data (N = 24,970) to conduct multivariable logistic regressions examining associations with having 1 or more sunburns in the past year and having 4 or more sunburns in the past year. Results Overall, 37.1% of adults experienced sunburn in the past year. The adjusted prevalence of sunburn was particularly common among adults aged 18–29 years (52.0%), those who repeatedly burn or freckle after 2 weeks in the sun (45.9%), whites (44.3%), indoor tanners (44.1%), those with a family history of melanoma (43.9%), and those who are US-born (39.5%). Physical activity, alcohol consumption, and overweight/obesity were positively associated with sunburn (all P < 0.001); sun protection behaviors were not significantly associated with sunburn (P = 0.35). Among those who were sunburned in the past year, 12.1% experienced 4 or more sunburns. Conclusion Sunburn is common, particularly among younger adults, those with a more sun-sensitive skin type, whites, those with a family history of melanoma, the highly physically active, and indoor tanners. Efforts are needed to facilitate sun-safety during outdoor recreation, improve the consistency of sun protection practices, and prevent sunburn, particularly among these subgroups. PMID:24589442

The relationship between behavioral states and pain responses to various NICU procedures in premature infants.

PubMed

Ahn, Youngmee

2006-06-01

An explanatory observational study was conducted to assess the behavioral state before and during various procedures in the neonatal intensive care unit (NICU) and to investigate the relationship between the behavioral state measured by Anderson Behavioral State Scoring System (ABSS) and the degree of pain responses as measured using CRIES (Crying, Requires O(2) for oxygen saturation above 95, Increased vital signs, Expression, and Sleeplessness.) and PIPP (Premature Infants' Pain Profile). Ninety-one observations in 6 NICU procedures were made from 54 infants with a mean gestational age (GA) of 30(+4) weeks and a mean body weight (BW) of 1484.87 g. A positive relationship was identified between ABSS and CRIES, both before (r=0.244, p=0.020) and during (r=0.745, p=0.000) the procedures, and between CRIES and PIPP (r=0.447, p=0.000) during the procedures. However, no correlation was identified between PIPP and ABSS before (r=-0.055, p=0.651) and during (r=0.214, p=0.074) the procedures. This study concluded that relatively healthy, premature infants are in a state of quiet or active sleep and can adequately express pain-related responses to the NICU procedures that are appropriate with the nature of stimulation. However, it was observed that clinicians tend to pay little attention to the state of premature infants before performing the procedures, regardless of their invasive and stimulatory nature. Further research needs to be conducted on the pain responses in physiologic and behavioral expression of critically ill infants who possibly have alteration and developmental limitations in response.

Presenting information on regulation values improves the public’s sense of safety: Perceived mercury risk in fish and shellfish and its effects on consumption intention

PubMed Central

Suzuki, Mai; Yamaguchi, Tomiko

2017-01-01

Risk communication aims to promote health and understanding through information exchange; however, explanations regarding the basis of regulation values for the public are insufficient. Moreover, it is unclear how information presentation affects the public’s sense of safety and their consumption intentions. We first investigated the relationship between perception of mercury-risk in fish and shellfish and individual attributes and knowledge. We then examined how presenting information on regulation values and primary factors regarding perception affected sense of safety toward regulations and food-consumption intentions. An online survey was conducted with Japanese individuals (N = 1148). Respondents were randomly assigned to one of three groups based on the presentation level of regulation values. People who frequently consumed tuna had a high perception of dread risk of mercury. This suggests that the dread risk perception of mercury does not determine tuna-type consumption behavior; rather, individuals’ consumption behavior determines dread risk perception of mercury. Among those with high tuna-type consumption, those receiving information that a safety factor of 10 times had been considered showed a significantly greater sense of safety than did the group that was not presented with information on regulation values (odds ratio (95% confidence interval): 2.04 (1.18–3.53), p < 0.05). However, presentation of regulation values showed a weak but significantly positive correlation with excessive intake of tuna-type fish (odds ratio: 2.95 (0.93–9.32), p < 0.10). Presenting the information on regulation values increases sense of safety; however, it may also lead to excessive intake. PMID:29267301

Balancing Hole and Electron Conduction in Ambipolar Split-Gate Thin-Film Transistors.

PubMed

Yoo, Hocheon; Ghittorelli, Matteo; Lee, Dong-Kyu; Smits, Edsger C P; Gelinck, Gerwin H; Ahn, Hyungju; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

2017-07-10

Complementary organic electronics is a key enabling technology for the development of new applications including smart ubiquitous sensors, wearable electronics, and healthcare devices. High-performance, high-functionality and reliable complementary circuits require n- and p-type thin-film transistors with balanced characteristics. Recent advancements in ambipolar organic transistors in terms of semiconductor and device engineering demonstrate the great potential of this route but, unfortunately, the actual development of ambipolar organic complementary electronics is currently hampered by the uneven electron (n-type) and hole (p-type) conduction in ambipolar organic transistors. Here we show ambipolar organic thin-film transistors with balanced n-type and p-type operation. By manipulating air exposure and vacuum annealing conditions, we show that well-balanced electron and hole transport properties can be easily obtained. The method is used to control hole and electron conductions in split-gate transistors based on a solution-processed donor-acceptor semiconducting polymer. Complementary logic inverters with balanced charging and discharging characteristics are demonstrated. These findings may open up new opportunities for the rational design of complementary electronics based on ambipolar organic transistors.

Women's beliefs about infertility and sexual behaviors: A qualitative study

PubMed Central

Bokaie, Mahshid; Simbar, Masoumeh; Ardekani, Seyed Mojtaba Yassini; Majd, Hamid Alavi

2016-01-01

Background: Infertility is a reproductive health problem and its prevalence is increasing in developing countries. This problem has some significant effects on the sexual behaviors of infertile women, especially during infertility treatment periods. Discovering the existing beliefs in the field of sexual and reproductive health and also determining the misconceptions would define the educational needs for providing sexual health programs for infertile women. Women should be able to distinguish risky behaviors from healthy behaviors that falsely have been marked as infertility-related behaviors. This qualitative study was conducted to determine women's beliefs about infertility and sexual behaviors among Iranian infertile women. Materials and Methods: The present study was a qualitative conventional content analysis study conducted on 15 infertile women and 8 key informants until reaching data saturation. Guba and Lincoln evaluative criteria were used for ensuring rigor of the study. Results: Data analysis defined three classes of beliefs that directly or indirectly affected sexual behaviors in infertile women: 1) Cultural, religious, or ethnic beliefs, 2) believing in the effect of diet on infertility, and 3) effect of the type of intercourse on getting pregnant. Conclusions: Three themes of religious, cultural, and ethnic beliefs, believing in the effect of diet on infertility, and the effect of the type of intercourse were the most important factors indicating sexual behaviors among infertile women. It seems that cultural and social matters are the most effective factors on sexual behaviors of infertile Iranian women. PMID:27563321

Structure and Electric Conduction in Pulsed Laser-Deposited ZnO Thin Films Individually Doped with N, P, or Na

NASA Astrophysics Data System (ADS)

Jiao, D. L.; Zhong, X. C.; Qiu, W. Q.; Zhang, H.; Liu, Z. W.; Zhang, G. Q.

2018-03-01

N-, P-, and Na-doped ZnO films with c-axis orientation were produced by pulsed laser deposition using N2O or O2 as the reaction gas. The effects of deposition temperature and deposition pressure on the lattice structure, morphology, and electric conduction have been investigated. High gas pressure leads to large-sized grains with large grain barriers, which cause a reduced mobility. P acts as an acceptor and the number of compensating defects in the P-doped film is reduced under high O2 pressure. Na also acts as an acceptor, and the effects of high temperature on Na-doped films are encouraging as the solubility of the dopant is high. However, high temperature may cause less incorporation of N and P in the film. In the present work, p-type conduction has not been obtained in N- and P-doped films despite a wide range of processing parameters employed. Na-doped films display an increasing trend towards p-type films at high temperatures and high O2 pressures. These results provide an insight on how these dopants behave in ZnO films and indicate that the careful selection of the deposition conditions is necessary in order to obtain p-type films by pulsed laser deposition.

Crystal growth and electrical properties of CuFeO 2 single crystals

NASA Astrophysics Data System (ADS)

Dordor, P.; Chaminade, J. P.; Wichainchai, A.; Marquestaut, E.; Doumerc, J. P.; Pouchard, M.; Hagenmuller, P.; Ammar, A.

1988-07-01

Delafossite-type CuFeO 2 single crystals have been prepared by a flux method: crystals obtained in a Cu crucible with LiBO 2 as flux are n-type whereas those prepared in a Pt crucible with a Cu 2O flux are p-type. Electrical measurements have revealed that n-type crystals exhibit weak anisotropic conductivities with large activation energies and small mobilities (r.t. values perpendicular and parallel to the c-axis: μ⊥ = 5 × 10 -5 and μ‖ = 10 -7 cm -2 V -1 sec -1). p-type crystals, less anisotropic, are characterized by low activation energies and higher mobilities ( μ⊥ = 34 and μ‖ = 8.9 cm 2 V -1 sec -1). A two -conduction-band model is proposed to account for the difference observed between the energy gap value deduced from photoelectrochemical measurements and the activation energy of the electrical conductivity in the intrinsic domain.

I Should but I Can’t: Controlled Motivation and Self-efficacy are Related to Disordered Eating Behaviors in Adolescents with Type 1 Diabetes

PubMed Central

Eisenberg, Miriam H.; Lipsky, Leah M.; Dempster, Katherine; Liu, Aiyi; Nansel, Tonja R.

2016-01-01

Purpose Among adolescents with type 1 diabetes, disordered eating behaviors (DEB) are more prevalent and have more serious health implications than in adolescents without diabetes, necessitating identification of modifiable correlates of DEB in this population. This study hypothesized that 1) autonomous motivation and 2) controlled motivation for healthy eating (i.e., eating healthfully because it’s important to oneself versus important to others respectively) are associated with DEB among adolescents with type 1 diabetes. The third hypothesis was that baseline healthy eating self-efficacy moderates these associations. Methods Adolescents with T1D (n = 90; 13–16 years) participating in a behavioral nutrition intervention efficacy trial reported DEB, controlled and autonomous motivation, and self-efficacy at baseline, 6, 12, and 18 months. Linear mixed models estimated associations of controlled and autonomous motivation with DEB, adjusting for treatment group, BMI, socio-economic status, age, and gender. Separate models investigated the interaction of self-efficacy with each motivation type. Results Controlled motivation was positively associated with DEB (B=2.18±.33, p<.001); the association was stronger for those with lower self-efficacy (B= 3.33±.55, p<.001) than those with higher self-efficacy (B=1.36±.36, p<.001). Autonomous motivation was not associated with DEB (B=−.70± .43, p=.11). Conclusions Findings identify controlled motivation for healthy eating as a novel correlate of DEB among adolescents with type 1 diabetes and show that self-efficacy can modify this association. Motivation and self-efficacy for healthy eating represent potential intervention targets to reduce DEB in adolescents with type 1 diabetes. PMID:27567063

Pressure-induced structural transition in chalcopyrite ZnSiP2

NASA Astrophysics Data System (ADS)

Bhadram, Venkata S.; Krishna, Lakshmi; Toberer, Eric S.; Hrubiak, Rostislav; Greenberg, Eran; Prakapenka, Vitali B.; Strobel, Timothy A.

2017-05-01

The pressure-dependent phase behavior of semiconducting chalcopyrite ZnSiP2 was studied up to 30 GPa using in situ X-ray diffraction and Raman spectroscopy in a diamond-anvil cell. A structural phase transition to the rock salt type structure was observed between 27 and 30 GPa, which is accompanied by soft phonon mode behavior and simultaneous loss of Raman signal and optical transmission through the sample. The high-pressure rock salt type phase possesses cationic disorder as evident from broad features in the X-ray diffraction patterns. The behavior of the low-frequency Raman modes during compression establishes a two-stage, order-disorder phase transition mechanism. The phase transition is partially reversible, and the parent chalcopyrite structure coexists with an amorphous phase upon slow decompression to ambient conditions.

Associations between media use and health information-seeking behavior on vaccinations in South Korea.

PubMed

Kim, Jiyeon; Jung, Minsoo

2017-09-11

Although vaccinations are critical for preventing emerging infectious diseases, scant research has been conducted on risk communication. With socio-economic characteristics, health behavior, and underlying diseases under control, we investigated associations between media use, health information-seeking behavior, health information type, and vaccination in the population. This study relied on a national survey of Korean adults (n = 1367). Participants were adult males and females age 20 and older. Web and face-to-face surveys were conducted throughout July 2014. The main outcome was vaccination (categorized as yes or no). Independent variables were time spent on media, frequency of health information-seeking behavior, and types of health information sought. Controlling for co-variates, logistic regression analysis was conducted to identify factors that influence Korean adults being vaccinated. Results revealed that accessible information about emerging infectious diseases, listening to the radio, and reading the newspaper were associated with increased odds of being vaccinated. Active seeking health information as well as being female and of higher socio-economic status were positively correlated with Korean adults being vaccinated. It is critical to promote health information-seeking behavior and use diverse media channels to increase acceptance and awareness of emerging infectious diseases and vaccinations. Because there are differences in vaccination awareness depending on social class, it is critical to reduce communication inequality, strengthen accessibility to vaccinations, and devise appropriate risk communication strategies that ensure Korean adults receive vaccinations.

Differential Effects of Tissue Culture Coating Substrates on Prostate Cancer Cell Adherence, Morphology and Behavior

PubMed Central

Liberio, Michelle S.; Sadowski, Martin C.; Soekmadji, Carolina; Davis, Rohan A.; Nelson, Colleen C.

2014-01-01

Weak cell-surface adhesion of cell lines to tissue culture surfaces is a common problem and presents technical limitations to the design of experiments. To overcome this problem, various surface coating protocols have been developed. However, a comparative and precise real-time measurement of their impact on cell behavior has not been conducted. The prostate cancer cell line LNCaP, derived from a patient lymph node metastasis, is a commonly used model system in prostate cancer research. However, the cells’ characteristically weak attachment to the surface of tissue culture vessels and cover slips has impeded their manipulation and analysis and use in high throughput screening. To improve the adherence of LNCaP cells to the culture surface, we compared different coating reagents (poly-l-lysine, poly-l-ornithine, collagen type IV, fibronectin, and laminin) and culturing conditions and analyzed their impact on cell proliferation, adhesion, morphology, mobility and gene expression using real-time technologies. The results showed that fibronectin, poly-l-lysine and poly-l-ornithine improved LNCaP cells adherence and provoked cell morphology alterations, such as increase of nuclear and cellular area. These coating reagents also induced a higher expression of F-actin and reduced cell mobility. In contrast, laminin and collagen type IV did not improve adherence but promoted cell aggregation and affected cell morphology. Cells cultured in the presence of laminin displayed higher mobility than control cells. All the coating conditions significantly affected cell viability; however, they did not affect the expression of androgen receptor-regulated genes. Our comparative findings provide important insight for the selection of the ideal coating reagent and culture conditions for the cancer cell lines with respect to their effect on proliferation rate, attachment, morphology, migration, transcriptional response and cellular cytoskeleton arrangement. PMID:25375165

Preschool Gender-Typed Play Behavior at Age 3.5 Years Predicts Physical Aggression at Age 13 Years.

PubMed

Kung, Karson T F; Li, Gu; Golding, Jean; Hines, Melissa

2018-05-01

Gender differences in play behavior and physical aggression have been consistently reported. Theoretical perspectives concerning evolutionary, social, and social-cognitive mechanisms suggest that male-typical play behavior during childhood increases subsequent physical aggression. The evidence supporting these connections is limited, however. The present study investigated the association between gender-typed play behavior in early childhood and physical aggression in early adolescence using a sample drawn from a longitudinal, population study, the Avon Longitudinal Study of Parents and Children. Based on gender-typed play behavior as measured by the Pre-School Activities Inventory at age 3.5 years, samples of masculine (64 boys, 60 girls), feminine (80 boys, 66 girls), and randomly selected control children (55 boys, 67 girls) were recruited at age 13 years and administered the Reinisch Aggression Inventory. After controlling for a range of sociodemographic variables, maternal characteristics, and behavioral problems, including hyperactivity and conduct problems at age 3.5, significant group differences in physical aggression at age 13 were found among children classified as masculine, control, and feminine at age 3.5. Masculine children exhibited significantly more physical aggression than control children or feminine children, and control children exhibited significantly more physical aggression than feminine children. The association between gender-typed play behavior and physical aggression was not moderated by sex. These results suggest that the degree of childhood gender-typed play behavior independently predicts the degree of physical aggression at adolescence in boys and in girls.

Night-waking and behavior in preschoolers: a developmental trajectory approach.

PubMed

Reynaud, Eve; Forhan, Anne; Heude, Barbara; Charles, Marie-Aline; Plancoulaine, Sabine

2018-03-01

The aim was to study, with a developmental approach, the longitudinal association between night-waking from age 2 to 5-6 years and behavior at age 5-6 years. Within the French birth cohort study Etude sur les Déterminants pré et post natals du développement et de la santé de l'ENfant (EDEN), repeated measures of children's night-waking were collected at age 2, 3 and 5-6 through parental questionnaires and were used to model night-waking trajectories. Behavior was assessed with the "Strengths and Difficulties Questionnaire," which provides five subscales measuring a child's conduct problems, emotional symptoms, peer relation problems, antisocial behavior, and hyperactivity/attention problems. The behavioral subscales were dichotomized at the tenth percentile. Multivariable logistic regressions, adjusted for parents' socio-economic factors, parental characteristics, and children's characteristics and sleep habits allowed us to study, in 1143 children, the association between night-waking trajectories from 2 to 5-6 years and behavior at age 5-6 years. The "2 to 5-6 rare night-waking" trajectory represented 78% of the included population (n = 896), and the "2 to 5-6 common night-waking" 22% (n = 247%). Children belonging to the "2 to 5-6 common night-waking trajectory" had, at age 5-6, increased risk of presenting emotional symptoms (odds ratio [OR] = 2.17, 95% CI = 1.27-3.70, p = 0.004), conduct problems (OR = 1.63, 95% CI = 1.00-2.65, p = 0.050), and hyperactivity/attention problems (OR = 1.61, 95% CI = 1.00-2.57, p = 0.049). After adjusting for baseline behavior at age two years, only the association with emotional symptoms remained significant (OR = 2.02, 95% CI = 1.15-3.55, p = 0.015). Results did not differ according to sex. Results suggest that the persistence of night-waking difficulties in early years is positively associated with emotional symptoms, hyperactivity/inattention, and conduct problems. Copyright © 2017 Elsevier B.V. All rights reserved.

Psychosocial and Clinical Outcomes of a Cognitive Behavioral Therapy for Asians and Pacific Islanders with Type 2 Diabetes: A Randomized Clinical Trial.

PubMed

Inouye, Jillian; Li, Dongmei; Davis, James; Arakaki, Richard

2015-11-01

Asian Americans and Pacific Islanders are twice as likely to be diagnosed with type 2 diabetes compared to Caucasians. The objective was to determine the effect of cognitive behavioral therapy on quality of life, general health perceptions, depressive symptoms, and glycemia in Asians and Pacific Islanders with type 2 diabetes. The design was a randomized controlled clinical trial comparing cognitive behavioral therapy to diabetes education and support for six weekly sessions. Participants were recruited from two endocrinology practices; 207 were enrolled. The cognitive behavioral therapy group was provided self-management tools which included biofeedback, breathing exercises, and stress relievers, while the diabetes education and support group included diabetes education and group discussions. Assessments of psychosocial and clinical outcomes were obtained before and after sessions and 12 months PostSession. Differences between the two groups were examined using linear mixed-effects models with linear contrasts. The cognitive behavioral therapy group had improved depressive symptom scores from PreSession to EndSession compared to the diabetes education and support group (P < .03), but the improvement did not extend to 12 months PostSession. Similar results were observed with misguided support scores in the Multidimensional Diabetes Questionnaire (P < .03) and susceptibility in health beliefs (P < .01), but no significant differences in HbA1c improvement were found between the two groups. Both interventions improved outcomes from baseline but were not sustained for 1 year.

Increased p-type conductivity in GaN{sub x}Sb{sub 1−x}, experimental and theoretical aspects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi; Makkonen, I.; Slotte, J.

2015-08-28

The large increase in the p-type conductivity observed when nitrogen is added to GaSb has been studied using positron annihilation spectroscopy and ab initio calculations. Doppler broadening measurements have been conducted on samples of GaN{sub x}Sb{sub 1−x} layers grown by molecular beam epitaxy, and the results have been compared with calculated first-principle results corresponding to different defect structures. From the calculated data, binding energies for nitrogen-related defects have also been estimated. Based on the results, the increase in residual hole concentration is explained by an increase in the fraction of negative acceptor-type defects in the material. As the band gapmore » decreases with increasing N concentration, the ionization levels of the defects move closer to the valence band. Ga vacancy-type defects are found to act as positron trapping defects in the material, and the ratio of Ga vacancy-type defects to Ga antisites is found to be higher than that of the p-type bulk GaSb substrate. Beside Ga vacancies, the calculated results imply that complexes of a Ga vacancy and nitrogen could be present in the material.« less

Social Support Network among People Living with HIV/AIDS in Iran

PubMed Central

Forouzan, Ameneh Setareh; Sajjadi, Homeira; Salimi, Yahya; Dejman, Masoumeh

2013-01-01

This study considers social network interactions as a potential source of support for individuals living with HIV/AIDS in Iran. This cross-sectional study was conducted on 224 people with HIV/AIDS who refer to behavioral counseling centers. Participants were randomly selected among all people with HIV/AIDS from these centers. Relatives were more reported as sources of support than nonrelatives. They were closer to participants, but there was difference between the closest type among relative and nonrelative supporters (P = 0.01). Mean of functional support with considering the attainable range 0–384 was low (126.74  (SD = 76.97)). Social support of participants has been found to be associated with CD4 cell count (P = 0.000), sex (P = 0.049), and network size (P = 0.000) after adjusted for other variables in the final model. Totally, in this study, many of participants had the static social support network that contained large proportions of family and relatives. The findings contribute to the evidence for promotion of knowledge about social support network and social support of people living with HIV/AIDS. PMID:23710351

Completely transparent ohmic electrode on p-type AlGaN for UV LEDs with core-shell Cu@alloy nanosilk network (Conference Presentation)

NASA Astrophysics Data System (ADS)

Cai, Duanjun; Wang, Huachun; Huang, Youyang; Wu, Chenping; Chen, Xiaohong; Gao, Na; Wei, Tongbo T.; Wang, Junxi; Li, Shuping; Kang, Junyong

2016-09-01

Metal nanowire networks hold a great promise, which have been supposed the only alternative to ITO as transparent electrodes for their excellent performance in touch screen, LED and solar cell. It is well known that the difficulty in making transparent ohmic electrode to p-type high-Al-content AlGaN conducting layer has highly constrained the further development of UV LEDs. On the IWN-2014, we reported the ohmic contact to n, p-GaN with direct graphene 3D-coated Cu nanosilk network and the fabrication of complete blue LED. On the ICNS-2015, we reported the ohmic contact to n-type AlGaN conducting layer with Cu@alloy nanosilk network. Here, we further demonstrate the latest results that a novel technique is proposed for fabricating transparent ohmic electrode to high-Al-content AlGaN p-type conducting layer in UV LEDs using Cu@alloy core-shell nanosilk network. The superfine copper nanowires (16 nm) was synthesized for coating various metals such as Ni, Zn, V or Ti with different work functions. The transmittance showed a high transparency (> 90%) over a broad wavelength range from 200 to 3000 nm. By thermal annealing, ohmic contact was achieved on p-type Al0.5Ga0.5N layer with Cu@Ni nanosilk network, showing clearly linear I-V curve. By skipping the p-type GaN cladding layer, complete UV LED chip was fabricated and successfully lit with bright emission at 276 nm.

Degenerate p-type conductivity in wide-gap LaCuOS1-xSex (x=0-1) epitaxial films

NASA Astrophysics Data System (ADS)

Hiramatsu, Hidenori; Ueda, Kazushige; Ohta, Hiromichi; Hirano, Masahiro; Kamiya, Toshio; Hosono, Hideo

2003-02-01

Epitaxial films of LaCuOS1-xSex (x=0-1) solid solution were grown on MgO (001) substrates and their electrical and optical properties were examined. Sharp emission due to room-temperature exciton with binding energy of ˜50 meV is observed for all x values. Hall mobility becomes large with an increase in the Se content and it reaches 8.0 cm2V-1s-1 in LaCuOSe, a comparable value to that of p-type GaN:Mg. Doping of Mg2+ ions at La3+ sites enhances a hole concentration up to 2.2×1020 cm-3, while maintaining the Hall mobility as large as 4.0 cm2V-1s-1. Consequently, a degenerate p-type electrical conduction with a conductivity of 140 S cm-1 was achieved.

Reducing and preventing internalizing and externalizing behavior problems in children with type 1 diabetes: a randomized controlled trial of the Triple P-Positive Parenting Program.

PubMed

Westrupp, E M; Northam, E; Lee, K J; Scratch, S E; Cameron, F

2015-11-01

Children with type 1 diabetes are at increased risk of mental health problems, which in turn are associated with poor glycemic control, diabetes-related complications, and long-term psychiatric morbidity. We tested the efficacy of the Triple P-Positive Parenting Program in reducing or preventing mental health problems and improving glycemic control in children with type 1 diabetes in a randomized controlled trial. Participants were recruited from the Diabetes Clinic, Royal Children's Hospital, Melbourne, Australia, and randomized to Triple P or standard diabetes care. The primary outcome was child internalizing and externalizing behavior problems 3 and 12 months postrandomization. Secondary outcomes were glycemic control, parent mental health, parenting skills, and family functioning at 3 and 12 months, and glycemic control at 24 months. A total of 76 participants were randomized (38 to intervention and 38 to control), 60 completed 3-month, and 57 completed 12-month assessments. Benefits of Triple P were evident at 3 months for parent mental health, parenting skills, and family functioning (p < 0.05), but not for child mental health or glycemic control, with little effect at 12 months. Prespecified subgroup analyses for children with pre-existing internalizing or externalizing behavior problems indicated greater improvements in child mental health, parent mental health, parenting skills, and diabetes family conflict (p < 0.05), but lower parenting self-efficacy at 3 months. Improvements in parent mental health and parenting competency associated with Triple P were sustained to 12 months for children with pre-existing mental health problems. This study provides some support for the efficacy of Triple P in improving parent and family outcomes, and reducing child internalizing and externalizing behavior problems primarily in children who have pre-existing mental health problems. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Navigational choice between reversal and curve during acidic pH avoidance behavior in Caenorhabditis elegans.

PubMed

Wakabayashi, Tokumitsu; Sakata, Kazumi; Togashi, Takuya; Itoi, Hiroaki; Shinohe, Sayaka; Watanabe, Miwa; Shingai, Ryuzo

2015-11-19

Under experimental conditions, virtually all behaviors of Caenorhabditis elegans are achieved by combinations of simple locomotion, including forward, reversal movement, turning by deep body bending, and gradual shallow turning. To study how worms regulate these locomotion in response to sensory information, acidic pH avoidance behavior was analyzed by using worm tracking system. In the acidic pH avoidance, we characterized two types of behavioral maneuvers that have similar behavioral sequences in chemotaxis and thermotaxis. A stereotypic reversal-turn-forward sequence of reversal avoidance caused an abrupt random reorientation, and a shallow gradual turn in curve avoidance caused non-random reorientation in a less acidic direction to avoid the acidic pH. Our results suggest that these two maneuvers were each triggered by a distinct threshold pH. A simulation study using the two-distinct-threshold model reproduced the avoidance behavior of the real worm, supporting the presence of the threshold. Threshold pH for both reversal and curve avoidance was altered in mutants with reduced or enhanced glutamatergic signaling from acid-sensing neurons. C. elegans employ two behavioral maneuvers, reversal (klinokinesis) and curve (klinotaxis) to avoid acidic pH. Unlike the chemotaxis in C. elegans, reversal and curve avoidances were triggered by absolute pH rather than temporal derivative of stimulus concentration in this behavior. The pH threshold is different between reversal and curve avoidance. Mutant studies suggested that the difference results from a differential amount of glutamate released from ASH and ASK chemosensory neurons.

Attachment representations and socio-emotional difficulties in alternative care: A comparison between residential, foster and family based children in Chile.

PubMed

Garcia Quiroga, Manuela; Hamilton-Giachritsis, Catherine; Ibañez Fanés, Margarita

2017-08-01

Attachment has been assessed in children living in alternative care (AC) settings, such as Residential Homes (RC) and Foster Care (FC). However, no study has been conducted to compare attachment styles in residential, foster and parental care conducted as usual in the same country at the same point in time. There is also a lack of studies conducted in less developed countries. Therefore, the aim of this study was to compare outcomes for children living in three different types of care in Chile. Three groups of children (N=77), living in (RC), (FC) and with biological parents (PC) were compared. Attachment styles, Indiscriminate Friendliness (IF) and socio-emotional/behavioral difficulties were assessed. Higher rates of secure attachment were observed in the RC group (36.1%) when compared to studies in RC in other countries (mean 18%). However, children in both types of AC were significantly more likely to have insecure and/or disorganized attachment styles than PC children. Higher rates of socio-emotional and behavioral problems were observed in RC (55.6%) and FC (50%) compared to PC (10%). Within type of AC, no significant differences were found, for attachment styles or for socio-emotional/behavioral difficulties, the only difference were the levels of IF, with children in RC having higher levels. As a conclusion, impact of placement in AC can vary between different countries, other factors, rather than only type of AC could better explain differences in attachment security for children. Implications for research and practices are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Little behaviors with big impacts: Exploring the sense of community surrounding socially conscious consumption

NASA Astrophysics Data System (ADS)

Devincenzo, Marie E. Hafey

The thesis is a study of socially conscious consumption practices and the meanings those behaviors have for consumers who participate in them. Psychological sense of community was used as the theoretical grounding for the study because it provided a way to examine socially conscious behaviors not solely as the behaviors of individuals but as behaviors within a social context with social meaning. Data were collected in two phases. First, a written, projective instrument compared cultural perceptions of various types of socially conscious consumption practices. Then, in-depth interviews were conducted to collect consumption narratives from participants and nonparticipants in a wind energy program called Blue Sky. The interviews were analyzed using a hermeneutical approach. The findings identified a new type of consumption community not recognized in prior literature: the principle based consumption community.

The association of physical and sexual abuse with HIV risk behaviors in adolescence and young adulthood: implications for public health.

PubMed

Cunningham, R M; Stiffman, A R; Doré, P; Earls, F

1994-03-01

This paper explores the relationship between changes in HIV risk behaviors and physical and sexual abuse. A stratified random sampling procedure selected 602 youths from a sample of 2,787 patients seen consecutively at public health clinics in 10 cities. Face-to-face structured interviews conducted since 1984-85 provide a history of change in risk behavior from adolescence to young adulthood. Univariate and bivariate analyses assessed differences in demographic and number and type of risk behaviors between those experiencing single or multiple types of abuse and those with no abuse history at all. The results show that a history of physical abuse, sexual abuse, or rape is related to engaging in a variety of HIV risk behaviors and to a continuation or increase in the total number of these behaviors between adolescence and young adulthood. This information might help practitioners to both prevent initial involvement in HIV risk behaviors and to prevent continuation of behaviors as youths move into young adulthood.

The status and predictors of hypertension preventive nutritional behaviors in adolescents based on the constructs of the Theory of Planned Behavior.

PubMed

Matlabi, Mohammad; Esmaeili, Reza; Moshki, Mahdi; Ranaei, Afsaneh; Haji, Alireza; Mehrabi, Rahele

2018-01-01

Malnutrition is an important factor affecting hypertensive incidence. Since the unhealthiest nutritional behaviors are rooted in childhood attitudes and experiences, applying educational interventions to these age groups will be most useful in the formation of preventive nutritional behaviors. To determine the predictive power of the TPB on hypertension in junior high-school students. The present cross-sectional study was conducted on 160 junior high-school students in Kashmar, Iran in academic year commencing 2-13-2014, selected through random sampling. The participants completed a researcher-made questionnaire consisting of a demographic information form and a section to evaluate the constructs of the TPB. The data collected were analyzed in SPSS-16 using the correlation Wilcoxon statistics test, the one-way ANOVA and multiple linear regression analysis. The mean age of the students was 13.51. A total of 47% of the students had snacked on potato chips and cheese puffs, 45% had eaten high-fat foods and 51.2% had eaten cookies and chocolates within the past week. The variable of behavioral intention predicted 32% of the variations in preventive nutritional behaviors by itself. The Pearson product-moment correlation analysis found that hypertension preventive nutritional behaviors were significantly correlated with attitude (p<0.001, r=0.38), perceived behavioral control (p<0.001, r=0.38), and behavioral intention. Moreover, significant correlations were observed between subjective norms and attitude (p<0.028, r=0.173), perceived behavioral control and attitude (p<0.003, r=0.231), behavioral intention and attitude (p<0.001, r=0.370), behavioral intention and subjective norms (p<0.030, r=0.171) and between behavioral intention and perceived behavioral control (p<0.001, r=0.484). The examined students revealed an adequate adherence to preventive nutritional behaviors. Nutrition education interventions should be developed based on variables such as behavioral intention and its determinants, i.e. attitude, perceived behavioral control and subjective norms.

A Note on the Fractal Behavior of Hydraulic Conductivity and Effective Porosity for Experimental Values in a Confined Aquifer

PubMed Central

De Bartolo, Samuele; Fallico, Carmine; Veltri, Massimo

2013-01-01

Hydraulic conductivity and effective porosity values for the confined sandy loam aquifer of the Montalto Uffugo (Italy) test field were obtained by laboratory and field measurements; the first ones were carried out on undisturbed soil samples and the others by slug and aquifer tests. A direct simple-scaling analysis was performed for the whole range of measurement and a comparison among the different types of fractal models describing the scale behavior was made. Some indications about the largest pore size to utilize in the fractal models were given. The results obtained for a sandy loam soil show that it is possible to obtain global indications on the behavior of the hydraulic conductivity versus the porosity utilizing a simple scaling relation and a fractal model in coupled manner. PMID:24385876

Does a future-oriented temporal perspective relate to body mass index, eating, and exercise? A meta-analysis.

PubMed

Sweeney, Allison M; Culcea, Ileana

2017-05-01

The present study aimed to quantify the magnitude of the association between future temporal perspective and Body Mass Index (BMI), diet, and exercise, respectively, and to clarify whether subjective future-focus scales or delay-discounting tasks are a more robust predictor of health behaviors. A systematic search was conducted for studies that included a dispositional measure of future temporal perspective and a measure of BMI, eating, and/or exercise behavior. Effect sizes for BMI, eating, and exercise were calculated using a random-effects model. The aggregate effect sizes for BMI (r = 0.14, k = 36, 95% CI = 0.10 - 0.18, p < 0.001), eating (r = 0.16, k = 18, 95% CI = 0.12-0.21, p < 0.001), and exercise (r = 0.12, k = 18, 95% CI = 0.09-0.14, p < 0.001) were significant and small in magnitude. Neither the type of future temporal perspective task (delay-discounting vs. subjective future-focus scale) nor the percentage of obese participants moderated the effect of temporal perspective on BMI, eating, or exercise. Although small in magnitude, the association between temporal perspective and health outcomes is comparable to other individual differences, such as personality and temperament. Future research is needed to examine how increasing the value placed on future outcomes can be integrated into long-term health behavior change interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Patterns of Service Use in Two Types of Managed Behavioral Health Care Plan

PubMed Central

Merrick, Elizabeth Levy; Hodgkin, Dominic; Hiatt, Deirdre; Horgan, Constance M.; Azzone, Vanessa; McCann, Bernard; Ritter, Grant; Zolotusky, Galina; McGuire, Thomas G.; Reif, Sharon

2009-01-01

Objective To describe service use patterns by level of care in two managed care products: employee assistance program (EAP) combined with behavioral health benefits, and standard behavioral health benefits. Methods This is a cross-sectional analysis of administrative data for 2004 from a national managed behavioral health care organization (MBHO). Utilization of 11 specific service categories was compared across products. The weighted sample reflected exact matching on sociodemographics (N= 710,014 unweighted; 286,750 weighted). Results In the EAP/behavioral health product,, the proportion of enrollees with outpatient mental health and substance abuse office visits (including EAP) was higher (p<.01), as was substance abuse day treatment/intensive outpatient care (p<.05). Use of residential substance abuse rehabilitation was lower (p<.05). Other differences were also found. Conclusion EAP/behavioral health and standard behavioral health care products had distinct utilization patterns in this large MBHO. In particular, greater use of certain outpatient services was observed within the EAP/behavioral health product. PMID:20044425

Frictional property of rocks in the Izu-Bonin-Mariana Forearc under high temperature and pressure conditions

NASA Astrophysics Data System (ADS)

Hyodo, G.; Takahashi, M.; Saito, S.; Hirose, T.

2014-12-01

The Kanto region in central Japan lies atop of three tectonic plates: the North American Plate, the Pacific Plate, and the Philippine Sea Plate. The collision and subduction of the Izu-Bonin-Mariana (IBM) arc on the Philippine Sea Plate into the Kanto region results in occurring the different type of earthquakes, including seismic slip (e.g., the Kanto earthquake) and aseismic creep (i.e., slow earthquakes around the Boso peninsula). The seismic and aseismic slip seems to generate side by side at almost same depth (probably nearly same P-T conditions). This study focus on frictional property of incoming materials to be subducted into the Kanto region, in order to examine a hypothesis that the different types of slips arise from different input materials. Thus, we have performed friction experiments on rocks that constitute the IBM forearc using a high P-T gas medium apparatus at AIST. We sampled five rocks (marl, boninite, andesite, sheared serpentinite and serpentinized dunite) recovered from the IBM forearc by Leg 125, Ocean Drilling Program (ODP Site 784, 786). The rocks were crushed and sieved into 10˜50 µm in grain size. Experiments were conducted at temperature of 300○C, confining pressure of 156 MPa, pore pressure of 60 MPa and axial displacement rates of 0.1 and 1 µm/s. For marl, andesite and boninite, a periodic stick-slip behavior appears at 1 µm/s. Rise time of the stick-slip behaviors are quite long (3.1, 9.9 and 14.2 sec, for marl, andesite and boninite, respectively). We called such events as a "slow stick-slip". Similar slow stick-slip behaviors were observed in previous studies (Noda and Shimamoto, 2010; Okazaki, 2013; Kaproth and Marone, 2013), but this is first time to recognize this characteristic slip behavior in sedimentary and igneous rocks. Although it is difficult to discuss the diverse slip behaviors observed at the Kanto region based on our limited experimental results, we will examine the conditions where the transition between stable and unstable sliding appears using the input materials and explore the generation mechanisms of earthquakes at the Kanto region.

Effect of case management on glycemic control and behavioral outcomes for chinese people with type 2 diabetes: A 2-year study.

PubMed

Yuan, Xiaodan; Wang, Fengmei; Fish, Anne Folta; Xue, Cunyi; Chen, Tao; Liu, Chao; Lou, Qingqing

2016-08-01

To examine the effect of case management on glycemic control and behavioral outcomes in adults with Type 2 diabetes in China. Participants were randomly assigned to a 1-year case management (CM) group (n=60) or control group (n=60). Monthly case management visits included identifying individuals' diabetes-related problems, setting goals, planning self-care, and evaluating progress. During a 1-year follow-up, all participants attended visits every 3 months without intervention. In the CM vs. the control group, HbA1c was reduced at 6 months compared to baseline (P=0.034), with trends at 12 and 24 months, and empowerment ability improved (P<0.05). Also in the CM vs. controls, total self-care behaviors, the frequency of exercise, blood glucose testing, and foot care were higher (P<0.001) at 12 months, and the percentage of individuals with HbA1c ≤7.0% was higher (P=0.035) at 24 months. The case management intervention in China was effective at 6 months and, based on trends in HbA1c at 12 and 24 months and results for behavioral outcomes, the intervention shows promise and warrants more research. A case management approach can enhance behavior change and glycemic control in Chinese with diabetes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of diet and exercise on weight-related outcomes for breast cancer survivors and their adult daughters: an analysis of the DAMES trial.

PubMed

Tometich, Danielle B; Mosher, Catherine E; Winger, Joseph G; Badr, Hoda J; Snyder, Denise C; Sloane, Richard J; Demark-Wahnefried, Wendy

2017-08-01

Few trials have aimed to promote diet and exercise behaviors in both cancer survivors and their family members and examine their associations with weight-related outcomes. We conducted a secondary analysis to examine associations between change in diet and exercise behaviors and weight-related outcomes for overweight breast cancer survivors and their overweight adult daughters in the Daughters And MothErS Against Breast Cancer (DAMES) randomized trial. The DAMES trial assessed the impact of two iteratively tailored, mailed print diet and exercise interventions against standard brochures over a 12-month period. This analysis examined change in diet and exercise behaviors and weight-related variables from baseline to post-intervention for the 50 breast cancer survivors and their adult daughters randomized to the intervention arms. To reduce the potential for type II error in this pilot, p values <0.10 were considered statistically significant. For mothers, change in diet quality was uniquely related to change in BMI (β = -0.12, p = 0.082), weight (β = -0.12, p = 0.060), and waist circumference (β = -0.38, p = 0.001), whereas change in caloric intake was related to waist circumference (β = 0.21, p = 0.002). For daughters, change in caloric intake was related to change in waist circumference (β = 0.12, p = 0.055). However, change in diet quality was not associated with weight-related outcomes in daughters. Additionally, change in exercise was not associated with weight-related outcomes in mothers or daughters. Findings support mail-based and other tailored interventions for weight loss in this population, with an emphasis on diet quality for breast cancer survivors and caloric intake for their adult daughters.

Thermoelectric Properties of Novel One-dimensional and Two-dimensional Systems Based on MoS2 Nanoribbons and Sheets

NASA Astrophysics Data System (ADS)

Arab, Abbas

Atomically thin materials such as hexagonal boron nitride (h-BN) and transition metal dichalcogenides (TMDCs) have attracted a lot of interest since the discovery of Graphene. Potential use of Graphene in semiconductor industry has been hindered by the fact that graphene is a semi metal with zero band gap. The difficulties in engineering band gap in graphene turn the focus light to inherent semiconducting two-dimensional (2D) materials; TMDCs. Bulk of TMDCs are formed by layers vertically stacked and weakly bonded together via weak van der Waals interactions. These weak interlayer forces make it possible to obtain monolayer by using scotch tape exfoliation or lithium-ion intercalation. Among the semiconducting members of TMDCs, MoS 2 is the most appealing candidate, partly due to its thermal stability and also for its natural abundance. Intensive study of electronic properties of MoS2 has revealed the desirable band gap (1.2 eV), good carrier xmobility (which is close to those of silicon thin films and graphene nanoribbons), thermal stability and a surface free from dangling bonds make it a perfect candidate for electronic and opto-electronic applications. Despite the fact that MoS2 has a high Seebeck coefficient, its thermoelectric properties have not studied as well as it should be. In this work, we have studied thermoelectric properties of monolayer and fewlayer MoS2 sheets in both armchair and zigzag orientations and also of monolayer MoS2 armchair nanoribbons. Density functional theory (DFT) using non-equilibrium Green's function (NEGF) method in ballistic transport regime of Landauer-Buttiker formulation in linear transport approximation has been implemented to calculate the transmission spectra and consequently electronic transport coefficients. Phonon transmission spectra are calculated based on parameterization of Stillinger-Weber potential. Thermoelectric figure of merit, ZT, is calculated using these electronic and phonon transmission spectra. In the case of MoS2 sheets, thermoelectric properties of monolayer, bilayer, trilayer and quadlayer in armchair and zigzag directions have been studied. Our results show that as number of layers increase from monolayer to quadlayer, both transmission spectrum and phonon thermal conductance increase. In addition, strong electronic and thermal anisotropy is found between zigzag and armchair orientations. Transmission coefficient and phonon thermal conductance of zigzag orientation is higher than those of armchair with the same number of layers. Electrical conductance and phonon thermal conductance are competing forces in achieving a high thermoelectric figure of merit. Advantage of having a higher electrical conductance in zigzag orientation has been nullified by having a higher phonon thermal conductance. In fact, our results show higher thermoelectric xifigure of merit for armchair oriented than zigzag oriented sheets. Also as number of layer decreases from quadlayer to monolayer, we are witnessing a higher thermoelectric figure of merit for both armchair and zigzag oriented sheets. Hence, the highest achieved thermoelectric figure of merit was obtained by monolayer armchair MoS2 sheet for both p-type and n-type semiconducting behavior. In case of MoS2 armchair nanoribbons, effect of several factors has been studied; width of nanoribbon, Sulfur vacancy and edge roughness. The electronic properties of nanoribbons are dominated by the presence of edge states that are dependent on the number of zigzag chains across the nanoribbon. In addition, it is found that the phonon thermal conductance of monolayer MoS2 armchair nanoribbon is smaller compared to MoS2 monolayer armchair sheet. This outcome can be explained by phonon edge scattering. The effect of this phonon edge scattering is more pronounced in narrower nanoribbons compared to wide ones which leads to higher thermoelectric figure of merit for narrow nanoribbons. The effect of edge roughness and sulfur vacancy on thermoelectric behavior of MoS2 nanoribbons is also studied. Our result shows that edge roughness decreased the thermoelectric figure of merit compared to those of a perfect nanoribbon as its impact on electrical conductance is more severe than on phonon thermal conductance. Sulfur vacancy, however, improved thermoelectric figure of merit of MoS2 nanoribbons. It has been shown that thermoelectric figure of merit as high as 4 and 3 at T = 500K can be achieved n-doped and p-doped MoS2 nanoribbons. The ability of getting a high thermoelectric figure of merit for both n-type and p-type behavior from the same material will be a huge boost to thermoelectric industry if realized.

Race/Ethnicity and gender differences in health intentions and behaviors regarding exercise and diet for adults with type 2 diabetes: A cross-sectional analysis

PubMed Central

2011-01-01

Background Self-management is the cornerstone of diabetes control and prevention of complications; however, it is undetermined whether differences in intention to adopt healthy lifestyles and actual healthy behavior exist across race/ethnic groups. This study evaluated the differences across racial-ethnic groups in self-reported medical advice received and health intentions and behaviors among adults with type 2 diabetes mellitus. Methods A cross-sectional analysis of the 2007 SHIELD US survey ascertained self-reported health intentions and behaviors for regular exercise, diet, and weight management among Non-Hispanic Caucasian (n = 2526), Non-Hispanic African-American (n = 706), and Hispanic (n = 179) respondents with type 2 diabetes. Results A similar proportion of respondents from each race-gender group (43%-56%) reported receiving healthcare advice to increase their exercise (P = 0.32). Significantly more minorities reported an intention to follow the exercise recommendation compared with Non-Hispanic Caucasians (P = 0.03). More Non-Hispanic African-American (29%) and Hispanic (27%) men reported exercising regularly compared with other race-gender groups (P = 0.02). Significantly more Non-Hispanic Caucasian women (74%) and Hispanic women (79%) reported trying to lose weight compared with other groups (P < 0.0001). Conclusions Differences in health intentions and healthy behaviors were noted across race-gender groups. More Non-Hispanic African-American men reported an intention to follow advice on exercising and self-report of exercising regularly was also higher compared with other race-gender groups. More Hispanic men reported high physical activity levels than other groups. Despite an increased willingness to follow healthcare recommendations for diet, >50% of respondents were obese among all race-gender groups. PMID:21729303

Race/Ethnicity and gender differences in health intentions and behaviors regarding exercise and diet for adults with type 2 diabetes: a cross-sectional analysis.

PubMed

Gavin, James R; Fox, Kathleen M; Grandy, Susan

2011-07-05

Self-management is the cornerstone of diabetes control and prevention of complications; however, it is undetermined whether differences in intention to adopt healthy lifestyles and actual healthy behavior exist across race/ethnic groups. This study evaluated the differences across racial-ethnic groups in self-reported medical advice received and health intentions and behaviors among adults with type 2 diabetes mellitus. A cross-sectional analysis of the 2007 SHIELD US survey ascertained self-reported health intentions and behaviors for regular exercise, diet, and weight management among Non-Hispanic Caucasian (n = 2526), Non-Hispanic African-American (n = 706), and Hispanic (n = 179) respondents with type 2 diabetes. A similar proportion of respondents from each race-gender group (43%-56%) reported receiving healthcare advice to increase their exercise (P = 0.32). Significantly more minorities reported an intention to follow the exercise recommendation compared with Non-Hispanic Caucasians (P = 0.03). More Non-Hispanic African-American (29%) and Hispanic (27%) men reported exercising regularly compared with other race-gender groups (P = 0.02). Significantly more Non-Hispanic Caucasian women (74%) and Hispanic women (79%) reported trying to lose weight compared with other groups (P < 0.0001). Differences in health intentions and healthy behaviors were noted across race-gender groups. More Non-Hispanic African-American men reported an intention to follow advice on exercising and self-report of exercising regularly was also higher compared with other race-gender groups. More Hispanic men reported high physical activity levels than other groups. Despite an increased willingness to follow healthcare recommendations for diet, >50% of respondents were obese among all race-gender groups.

Reviewing for "Beyond Behavior": An Editor's Guide for Submitting a Comprehensive and Meaningful Review

ERIC Educational Resources Information Center

Mooney, Paul; Ryan, Joseph B.

2018-01-01

Reviewing manuscripts is an integral part of the publication process. Unfortunately, few scholars receive training in this skill. This article provides an overview of what it takes to conduct a quality review of a manuscript submission for a practitioner journal. The editors describe the manuscript types published by "Beyond Behavior"…

Factors Associated with Tobacco Use Among Iranian Adolescents: An Application of Protection Motivation Theory.

PubMed

Sabzmakan, Leila; Ghasemi, Mahmood; Asghari Jafarabadi, Mohammad; Kamalikhah, Tahereh; Chaleshgar Kordasiabi, Mosharafeh

2018-01-09

Tobacco use is a significant predisposing factor to many diseases. Protection motivation theory is a well-suited theory, since fear can motivate individuals to change their unhealthy behaviors. This study was conducted to examine the associations between the constructs of this theory with intention and tobacco use behavior. The present cross-sectional study was conducted in Noshahr, Iran. The participants were 440 high school boys selected using a stratified random sampling in 2016. A questionnaire about tobacco use based on protection motivation theory was developed and its validity and reliability were assessed. The questionnaire included the demographic information, the constructs of theory, and tobacco use behavior. Structural equation modeling was used to test the associations between the constructs with intention and tobacco use. The variables of perceived vulnerability (β = 0/137, P < 0.001), fear (β = 0/149, P < 0.001), self-efficacy (β = 0/249, P < 0.001), perceived intrinsic reward (β = -0.285, P < 0.001), threat appraisal (β = -0.25, P < 0.001), and coping appraisal (β = 0.358, P < 0.001) had direct effect and are significant with intention. Moreover, perceived vulnerability (β = -0.158, P < 0.001), fear (β = -0.172, P < 0.001), self-efficacy (β = -0.288, P < 0.001), perceived intrinsic reward (β = 0.329, P < 0.001), threat appraisal (β = 0.265, P < 0.001), and coping appraisal (β = -0.379, P < 0.001) affected tobacco use indirectly through intention and were significantly associated with behavior. Also, intention had direct effect and is significant with tobacco use (β = -1.156, P < 0.001). The protection motivation theory provides a useful framework for investigating factors of tobacco use among male students. Future tobacco prevention interventions should focus on increasing the vulnerability and fear, decreasing intrinsic reward, and improving self-efficacy to reduce tobacco use.

Transdisciplinary translational behavioral (TDTB) research: opportunities, barriers, and innovations.

PubMed

Czajkowski, Susan M; Lynch, Minda R; Hall, Kara L; Stipelman, Brooke A; Haverkos, Lynne; Perl, Harold; Scott, Marcia S; Shirley, Mariela C

2016-03-01

The translation of basic behavioral science discoveries into practical strategies represents a promising approach to developing more effective preventive interventions to improve health. Since translational research inevitably involves making use of diverse perspectives from multiple disciplines, it is best conducted as a transdisciplinary enterprise. In this paper, we discuss current strategies used by NIH to support transdisciplinary translational behavioral (TDTB) research, summarize successful efforts, and highlight challenges encountered in conducting such work (ranging from conceptual to organizational to methodological). Using examples from NIH-funded projects we illustrate the potential benefits of, and barriers to, pursuing this type of research and discuss next steps and potential future directions for NIH-supported TDTB research.

Why do young adolescents bully? Experience in Malaysian schools.

PubMed

Wan Ismail, Wan Salwina; Nik Jaafar, Nik Ruzyanei; Sidi, Hatta; Midin, Marhani; Shah, Shamsul Azhar

2014-01-01

To determine sociodemographic and psychological factors associated with bullying behavior among young adolescents in Malaysia. This is a cross-sectional study of four hundred ten 12-year-old adolescents from seven randomly sampled schools in the Federal Territory of Kuala Lumpur, Malaysia. Sociodemographic features of the adolescents and their parents, bullying behavior (Malaysian Bullying Questionnaire), ADHD symptoms (Conners Rating Scales), and internalizing and externalizing behavior (Child Behaviour Checklist) were obtained from adolescents, parents and teachers, respectively. Only male gender (OR=7.071, p=0.01*, CI=1.642-30.446) was a significant sociodemographic factor among bullies. Predominantly hyperactive (OR=2.285, p=0.00*, CI=1.507-3.467) and inattentive ADHD symptoms reported by teachers (OR=1.829, p=0.03*, CI=1.060-3.154) and parents (OR=1.709, p=0.03*, CI=1.046-2.793) were significant risk factors for bullying behavior while combined symptoms reported by young adolescents (OR=0.729, p=0.01*, CI=0.580-0.915) and teachers (OR=0.643, p=0.02*, CI=0.440-0.938) were protective against bullying behavior despite the influence of conduct behavior (OR=3.160, p=0.00*, CI=1.600-6.241). Internalizing behavior, that is, withdrawn (OR=0.653, p=0.04*, CI=0.436-0.977) and somatic complaints (OR=0.619, p=0.01*, CI=0.430-0.889) significantly protect against bullying behavior. Recognizing factors associated with bullying behavior, in particular factors distinctive to the local population, facilitates in strategizing effective interventions for school bullying among young adolescents in Malaysian schools. Copyright © 2014 Elsevier Inc. All rights reserved.

Band gap narrowing in n-type and p-type 3C-, 2H-, 4H-, 6H-SiC, and Si

NASA Astrophysics Data System (ADS)

Persson, C.; Lindefelt, U.; Sernelius, B. E.

1999-10-01

Doping-induced energy shifts of the conduction band minimum and the valence band maximum have been calculated for n-type and p-type 3C-, 2H-, 4H-, 6H-SiC, and Si. The narrowing of the fundamental band gap and of the optical band gap are presented as functions of ionized impurity concentration. The calculations go beyond the common parabolic treatments of the ground state energy dispersion by using energy dispersion and overlap integrals from band structure calculations. The nonparabolic valence band curvatures influence strongly the energy shifts especially in p-type materials. The utilized method is based on a zero-temperature Green's function formalism within the random phase approximation with local field correction according to Hubbard. We have parametrized the shifts of the conduction and the valence bands and made comparisons with recently published results from a semi-empirical model.

Charge-Transfer-Induced p-Type Channel in MoS2 Flake Field Effect Transistors.

PubMed

Min, Sung-Wook; Yoon, Minho; Yang, Sung Jin; Ko, Kyeong Rok; Im, Seongil

2018-01-31

The two-dimensional transition-metal dichalcogenide semiconductor MoS 2 has received extensive attention for decades because of its outstanding electrical and mechanical properties for next-generation devices. One weakness of MoS 2 , however, is that it shows only n-type conduction, revealing its limitations for homogeneous PN diodes and complementary inverters. Here, we introduce a charge-transfer method to modify the conduction property of MoS 2 from n- to p-type. We initially deposited an n-type InGaZnO (IGZO) film on top of the MoS 2 flake so that electron charges might be transferred from MoS 2 to IGZO during air ambient annealing. As a result, electron charges were depleted in MoS 2 . Such charge depletion lowered the MoS 2 Fermi level, which makes hole conduction favorable in MoS 2 when optimum source/drain electrodes with a high work function are selected. Our IGZO-supported MoS 2 flake field effect transistors (FETs) clearly display channel-type conversion from n- to p-channel in this way. Under short- and long-annealing conditions, n- and p-channel MoS 2 FETs are achieved, respectively, and a low-voltage complementary inverter is demonstrated using both channels in a single MoS 2 flake.

Milestone-Based Assessments Are Superior to Likert-Type Assessments in Illustrating Trainee Progression

PubMed Central

Bartlett, Kathleen W.; Whicker, Shari A.; Bookman, Jack; Narayan, Aditee P.; Staples, Betty B.; Hering, Holly; McGann, Kathleen A.

2015-01-01

Background The Pediatrics Milestone Project uses behavioral anchors, narrative descriptions of observable behaviors, to describe learner progression through the Accreditation Council for Graduate Medical Education competencies. Starting June 2014, pediatrics programs were required to submit milestone reports for their trainees semiannually. Likert-type scale assessment tools were not designed to inform milestone reporting, creating a challenge for Clinical Competency Committees. Objective To determine if milestone-based assessments better stratify trainees by training level compared to Likert-type assessments. Methods We compared assessment results for 3 subcompetencies after changing from a 5-point Likert scale to milestone-based behavioral anchors in July 2013. Program leadership evaluated the new system by (1) comparing PGY-1 mean scores on Likert-type versus milestone-based assessments; and (2) comparing mean scores on the Likert-type versus milestone-based assessments across PGY levels. Results Mean scores for PGY-1 residents were significantly higher on the prior year's Likert-type assessments than milestone-based assessments for all 3 subcompetencies (P < .01). Stratification by PGY level was not observed with Likert-type assessments (eg, interpersonal and communication skills 1 [ICS1] mean score for PGY-1, 3.99 versus PGY-3, 3.98; P  =  .98). In contrast, milestone-based assessments demonstrated stratification by PGY level (eg, the ICS1 mean score was 3.06 for PGY-1, 3.83 for PGY-2, and 3.99 for PGY-3; P < .01 for PGY-1 versus PGY-3). Significantly different means by trainee level were noted across 21 subcompetencies on milestone-based assessments (P < .01 for PGY-1 versus PGY-3). Conclusions Initial results indicate milestone-based assessments stratify trainee performance by level better than Likert-type assessments. Average PGY-level scores from milestone-based assessments may ultimately provide guidance for determining whether trainees are progressing at the expected pace. PMID:26217427

Identification of loop D domain amino acids in the human Aquaporin-1 channel involved in activation of the ionic conductance and inhibition by AqB011

NASA Astrophysics Data System (ADS)

Kourghi, Mohamad; De Ieso, Michael L.; Nourmohammadi, Saeed; Pei, Jinxin V.; Yool, Andrea J.

2018-04-01

Aquaporins are integral proteins that facilitate the transmembrane transport of water and small solutes. In addition to enabling water flux, mammalian Aquaporin-1 (AQP1) channels activated by cyclic GMP can carry non-selective monovalent cation currents, selectively blocked by arylsulfonamide compounds AqB007 (IC50 170 µM) and AqB011 (IC50 14 µM). In silico models suggested that ligand docking might involve the cytoplasmic loop D (between AQP1 transmembrane domains 4 and 5), but the predicted site of interaction remained to be tested. Work here shows that mutagenesis of two conserved arginine residues in loop D slowed the activation of the AQP1 ion conductance and impaired the sensitivity of the channel to block by AqB011. Substitution of residues in loop D with proline showed effects on ion conductance amplitude that varied with position, suggesting that the structural conformation of loop D is important for AQP1 channel gating. Human AQP1 wild type, AQP1 mutant channels with alanines substituted for two arginines (R159A+R160A), and mutants with proline substituted for single residues threonine (T157P), aspartate (D158P), arginine (R159P, R160P) or glycine (G165P) were expressed in Xenopus laevis oocytes. Conductance responses were analyzed by two-electrode voltage clamp. Optical osmotic swelling assays and confocal microscopy were used to confirm mutant and wild type AQP1-expressing oocytes were expressed in the plasma membrane. After application of membrane-permeable cGMP, R159A+R160A channels had a significantly slower rate of activation as compared with wild type, consistent with impaired gating. AQP1 R159A+R160A channels showed no significant block by AqB011 at 50 µM, in contrast to the wild type channel which was blocked effectively. T157P, D158P and R160P mutations had impaired activation compared to wild type; R159P showed no significant effect; and G165P appeared to augment the conductance amplitude. These findings provide evidence for the role of the loop D as a gating domain for AQP1 ion channels, and identify the likely site of interaction of AqB011 in the proximal loop D sequence.

Prediction of three social cognitive-motivational structure types.

PubMed

Malerstein, A J; Ahern, M M; Pulos, S

2001-10-01

Previously, using interviews from Baumrind's longitudinal study, three cognitive-motivational structures (CMSs) were predicted in 68 adolescents from caregiving settings and from the CMS types of their mothers, based on the mothers' interviews elicited six years earlier. CMS theory proposes that during Piaget's Concrete Operational Period care-receiving influences the child's adoption of a social cognitive style, which corresponds to one of Piaget's stages of cognitive development. One who is classified as an Operational experiences the caregiving setting as tuned to the child's long-term interests, becomes focused on function and control of function and grasps the distinctions between and gradations of social attributes. One classified as future Intuitive experiences the caregiving as insufficient or unreliable and becomes focused on getting and having, and assesses social situations based on current striking dimensions. A person classified as being future Symbolic experiences the caregiving as out of tune with the self or the world, becomes focused on identity and emotional closeness, and may define self or object by a single attribute. This previous study did not distinguish between the influence of caregiving (including mothers' CMS) on the formation of adolescent CMS type and the possible constancy of CMS type from ages 9 to 15 years. The current study was designed to distinguish between these two possibilities, using data from 67 of the same mothers. Mothers' interviews were purged of descriptions of her child's behavior. Another interview was composed of the purged descriptions of child behavior. This was also done for interviews held when the child was 4 and 15 as well as at 9. From interviews with descriptions of child behavior purged, mother's CMS type at the child's age of 4 and 9 yr. agreed with her adolescent's previously assigned CMS type (p<.05), and caregiving setting at 9 years predicted the adolescent's CMS type (p<.05). From interviews composed of descriptions of only the child's behavior, adolescent CMS type agreed with previously assigned adolescent CMS type (p<.01). Findings were consonant with the idea that CMS type formation is influenced at about Age 9 and sufficiently established to be recognized at Age 15.

Worker substance use, workplace problems and the risk of occupational injury: a matched case-control study.

PubMed

Spicer, Rebecca S; Miller, Ted R; Smith, Gordon S

2003-07-01

This study examines the tendency toward problem behavior as an explanation for the relationship between problem substance use and occupational injury. The authors used a matched case-control study nested in a cohort of 26,413 workers, in which cases (n = 3,994) were workers suffering an occupational injury. Five controls per case (n = 19,970) were selected from the cohort of workers active on the day of the injury and matched on job type. Conditional logistic regression modeled the association of problem substance use with occupational injury, controlling for problem behaviors and worker characteristics. Problem substance use was indicated indirectly if any of the following were alcohol/drug-involved during the comparison period: Employee Assistance Program visit, excused absence or disciplinary action. Discipline records identified minor (absenteeism) and serious (dishonesty, theft, assault, harassment, disrespect) problem behaviors during the comparison period. The odds of injury among workers with an indicator of problem substance use was 1.35 (p = .015) times greater than the odds among workers without an indicator, controlling for job type and demographics as well as adjusting for exposure. This ratio declined to 1.21 (p = .138) when problem behaviors were also controlled for. Minor and serious problem behaviors were significantly associated with occupational injury (odds ratio [OR] = 1.73, p < .001, and OR = 2.19, p < .001, respectively), controlling for demographics and substance use. The relationship of problem substance use with occupational injury was weak when problem behaviors were controlled for, suggesting that this relationship, observed in previous studies, may be explained by a workers tendency toward problem behaviors. Workplace injury prevention programs should address the expression of problem behaviors as a complement to drug and alcohol deterrent programs.

Behaviors of beryllium compensation doping in InGaAsP grown by gas source molecular beam epitaxy

NASA Astrophysics Data System (ADS)

Ma, Y. J.; Zhang, Y. G.; Gu, Y.; Xi, S. P.; Chen, X. Y.; Liang, Baolai; Juang, Bor-Chau; Huffaker, Diana L.; Du, B.; Shao, X. M.; Fang, J. X.

2017-07-01

We report structural properties as well as electrical and optical behaviors of beryllium (Be)-doped InGaAsP lattice-matched to InP grown by gas source molecular beam epitaxy. P type layers present a high degree of compensation on the order of 1018 cm-3, and for Be densities below 9.5×1017 cm-3, they are found to be n type. Enhanced incorporation of oxygen during Be doping is observed by secondary ion mass spectroscopy. Be in forms of interstitial donors or donor-like Be-O complexes for cell temperatures below 800°C is proposed to account for such anomalous compensation behaviors. A constant photoluminescence energy of 0.98 eV without any Moss-Burstein shift for Be doping levels up to 1018 cm-3 along with increased emission intensity due to passivation effect of Be is also observed. An increasing number of minority carriers tend to relax via Be defect state-related Shockley-Read-Hall recombination with the increase of Be doping density.

Influencing factors on hand hygiene behavior of nursing students based on theory of planned behavior: A descriptive survey study.

PubMed

Jeong, Sun Young; Kim, Kyung Mi

2016-01-01

Hand hygiene is the single most important measure to prevent transmission of infection, but the compliance rate of healthcare workers is relatively low. This study was conducted to identify the knowledge, beliefs, behavior, and affecting factors about hand hygiene among nursing students. A descriptive survey study. The study was carried out in two South Korean nursing schools. A total 208 nursing students participated in this study. Questionnaires were used to collect data. The percentage of correct answers in the survey section concerning hand hygiene knowledge was 68.1%. No significant difference in the knowledge, behavioral beliefs, normative beliefs, or control beliefs data was found related to general characteristics. Behavioral beliefs correlated with normative beliefs (r=.25, p<.001) and hand hygiene behavior (r=.17, p=.017), and control beliefs correlated with hand hygiene behavior (r=.18, p=.010). The results suggest that knowledge is not enough to change the beliefs related to hand hygiene; positive behavioral beliefs and strong control beliefs are also needed to increase hand hygiene compliance. Copyright © 2015 Elsevier Ltd. All rights reserved.

Remote p-type Doping in GaSb/InAs Core-shell Nanowires

PubMed Central

Ning, Feng; Tang, Li-Ming; Zhang, Yong; Chen, Ke-Qiu

2015-01-01

By performing first-principles calculation, we investigated the electronic properties of remotely p-type doping GaSb nanowire by a Zn-doped InAs shell. The results show that for bare zinc-blende (ZB) [111] GaSb/InAs core-shell nanowire the Zn p-type doped InAs shell donates free holes to the non-doped GaSb core nanowire without activation energy, significantly increasing the hole density and mobility of nanowire. For Zn doping in bare ZB [110] GaSb/InAs core-shell nanowire the hole states are compensated by surface states. We also studied the behaviors of remote p-type doing in two-dimensional (2D) GaSb/InAs heterogeneous slabs, and confirmed that the orientation of nanowire side facet is a key factor for achieving high efficient remote p-type doping. PMID:26028535

Disturbed eating behavior and eating disorders in preteen and early teenage girls with type 1 diabetes: a case-controlled study.

PubMed

Colton, Patricia; Olmsted, Marion; Daneman, Denis; Rydall, Anne; Rodin, Gary

2004-07-01

To compare the prevalence of eating disturbances in preteen and early teenage girls with type 1 diabetes to their nondiabetic peers. A cross-sectional, case-controlled study of 101 girls with type 1 diabetes, ages 9-14 years, and 303 age-matched, female nondiabetic control subjects was conducted. Participants completed a Children's Eating Disorder Examination interview. Socioeconomic status, BMI, and diabetes-related variables were assessed. Groups were compared using chi(2) analyses. Binge eating; the use of intense, excessive exercise for weight control; the combination of two disturbed eating-related behaviors; and subthreshold eating disorders were all more common in girls with type 1 diabetes. Metabolic control was not related to eating behavior in this study population. Eating disturbances, though mostly mild, were significantly more common in preteen and early teenage girls with type 1 diabetes. Screening and prevention programs for this high-risk group should begin in the preteen years.

BclxL changes conformation upon binding to wild-type but not mutant p53 DNA binding domain.

PubMed

Hagn, Franz; Klein, Christian; Demmer, Oliver; Marchenko, Natasha; Vaseva, Angelina; Moll, Ute M; Kessler, Horst

2010-01-29

p53 can induce apoptosis through mitochondrial membrane permeabilization by interaction of its DNA binding region with the anti-apoptotic proteins BclxL and Bcl2. However, little is known about the action of p53 at the mitochondria in molecular detail. By using NMR spectroscopy and fluorescence polarization we characterized the binding of wild-type and mutant p53 DNA binding domains to BclxL and show that the wild-type p53 DNA binding domain leads to structural changes in the BH3 binding region of BclxL, whereas mutants fail to induce such effects due to reduced affinity. This was probed by induced chemical shift and residual dipolar coupling data. These data imply that p53 partly achieves its pro-apoptotic function at the mitochondria by facilitating interaction between BclxL and BH3-only proteins in an allosteric mode of action. Furthermore, we characterize for the first time the binding behavior of Pifithrin-mu, a specific small molecule inhibitor of the p53-BclxL interaction, and present a structural model of the protein-ligand complex. A rather unusual behavior is revealed whereby Pifithrin-mu binds to both sides of the protein-protein complex. These data should facilitate the rational design of more potent specific BclxL-p53 inhibitors.

Mid-aged and aged wild-type and progestin receptor knockout (PRKO) mice demonstrate rapid progesterone and 3alpha,5alpha-THP-facilitated lordosis.

PubMed

Frye, C A; Sumida, K; Lydon, J P; O'Malley, B W; Pfaff, D W

2006-05-01

Progesterone (P) and its 5alpha-reduced metabolite, 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-THP), facilitate sexual behavior of rodents via agonist-like actions at intracellular progestin receptors (PRs) and membrane GABA(A)/benzodiazepine receptor complexes (GBRs), respectively. Given that ovarian secretion of progestins declines with aging, whether or not senescent mice are responsive to progestins was of interest. Homozygous PR knockout (PRKO) or wild-type mice that were between 10-12 (mid-aged) or 20-24 (aged) months of age were administered P or 3alpha,5alpha-THP, and the effect on lordosis were examined. Effects of a progestin-priming regimen that enhances PR-mediated (experiment 1) or more rapid, PR-independent effects of progestins (experiments 2 and 3) on sexual behavior were examined. Levels of P, 3alpha,5alpha-THP, and muscimol binding were examined in tissues from aged mice (experiment 4). Wild-type, but not PRKO, mice were responsive when primed with 17beta-estradiol (E(2); 0.5 microg) and administered P (500 microg, subcutaneously). Mid-aged wild-type mice demonstrated greater increases in lordosis 6 h later compared to their pre-P, baseline test than did aged wild-type mice (experiment 1). Lordosis of younger and older wild-type, but not PRKO, mice was significantly increased within 5 min of intravenous (IV) administration of P (100 ng), compared with E(2)-priming alone (experiment 2). However, wild-type and PRKO mice demonstrated significant increases in lordosis 5 min after IV administration of 3alpha,5alpha-THP, an effect which was more pronounced in mid-aged than in aged animals (100 ng-experiment 3). In tissues from aged wild-type and PRKO mice, levels of P, 3alpha,5alpha-THP, and muscimol binding were increased by P administration (experiment 4). PR binding was lower in the cortex of PRKO than that of wild-type mice. Mid-aged and aged PRKO and wild-type mice demonstrated rapid P or 3alpha,5alpha-THP-facilitated lordosis that may be, in part, independent of activity at PRs.

The Relationship between Parental Depressive Symptoms, Family Type, and Adolescent Functioning

PubMed Central

Sieh, Dominik Sebstian; Visser-Meily, Johanna Maria Augusta; Meijer, Anne Marie

2013-01-01

It is evident that parental depressive symptoms negatively influence adolescent behavior and various psychosocial outcomes. Certain family types like families with a chronically ill parent and single parent families are more vulnerable to parental depressive symptoms. However, the relationship between these symptoms, family type, and adolescent functioning remains largely unclear. This study examined relations between self-report of parental depressive symptoms and adolescent functioning in 86 two-parent families including a parent with a chronic medical condition, 94 families with healthy single parents, and 69 families with 2 healthy parents (comparison group). Parents completed the Beck Depression Inventory. Adolescents filled in the Youth Self-Report measuring problem behavior, and other instruments measuring psychosocial outcomes (stress, grade point average, school problems, and self-esteem). Multilevel analyses were used to examine the effects of family type, parental depressive symptoms, adolescents' gender and age, and interaction effects on adolescent functioning. The results indicated that adolescents with chronically ill and single parents had a lower grade point average (p<.01) than the comparison group. Adolescents of single parents reported more internalizing problems (p<.01) and externalizing problems (p<.05) than children from the other family types. Parental depressive symptoms were strongly related to child report of stress (p<.001). Adolescents of depressed chronically ill parents were particularly vulnerable to internalizing problems (interaction effect, p<.05). Older children and girls, and especially older girls, displayed more internalizing problems and stress. It can be concluded that growing up with a chronically ill parent in a family with 2 parents may have less impact on adolescent problem behavior than growing up in a single parent family. Health practitioners are encouraged to be attentive to the unique and combined influence of family type and parental depressive symptoms on adolescent functioning. Older and female adolescents deserve particular attention. PMID:24260457

Making Teamwork Work: Team Knowledge for Team Effectiveness.

PubMed

Guchait, Priyanko; Lei, Puiwa; Tews, Michael J

2016-01-01

This study examined the impact of two types of team knowledge on team effectiveness. The study assessed the impact of taskwork knowledge and teamwork knowledge on team satisfaction and performance. A longitudinal study was conducted with 27 service-management teams involving 178 students in a real-life restaurant setting. Teamwork knowledge was found to impact both team outcomes. Furthermore, team learning behavior was found to mediate the relationships between teamwork knowledge and team outcomes. Educators and managers should therefore ensure these types of knowledge are developed in teams along with learning behavior for maximum effectiveness.

Guided Growth of Horizontal p-Type ZnTe Nanowires

PubMed Central

2016-01-01

A major challenge toward large-scale integration of nanowires is the control over their alignment and position. A possible solution to this challenge is the guided growth process, which enables the synthesis of well-aligned horizontal nanowires that grow according to specific epitaxial or graphoepitaxial relations with the substrate. However, the guided growth of horizontal nanowires was demonstrated for a limited number of materials, most of which exhibit unintentional n-type behavior. Here we demonstrate the vapor–liquid–solid growth of guided horizontal ZnTe nanowires and nanowalls displaying p-type behavior on four different planes of sapphire. The growth directions of the nanowires are determined by epitaxial relations between the nanowires and the substrate or by a graphoepitaxial effect that guides their growth along nanogrooves or nanosteps along the surface. We characterized the crystallographic orientations and elemental composition of the nanowires using transmission electron microscopy and photoluminescence. The optoelectronic and electronic properties of the nanowires were studied by fabricating photodetectors and top-gate thin film transistors. These measurements showed that the guided ZnTe nanowires are p-type semiconductors and are photoconductive in the visible range. The guided growth of horizontal p-type nanowires opens up the possibility of parallel nanowire integration into functional systems with a variety of potential applications not available by other means. PMID:27885331

Guided Growth of Horizontal p-Type ZnTe Nanowires.

PubMed

Reut, Gilad; Oksenberg, Eitan; Popovitz-Biro, Ronit; Rechav, Katya; Joselevich, Ernesto

2016-08-04

A major challenge toward large-scale integration of nanowires is the control over their alignment and position. A possible solution to this challenge is the guided growth process, which enables the synthesis of well-aligned horizontal nanowires that grow according to specific epitaxial or graphoepitaxial relations with the substrate. However, the guided growth of horizontal nanowires was demonstrated for a limited number of materials, most of which exhibit unintentional n-type behavior. Here we demonstrate the vapor-liquid-solid growth of guided horizontal ZnTe nanowires and nanowalls displaying p-type behavior on four different planes of sapphire. The growth directions of the nanowires are determined by epitaxial relations between the nanowires and the substrate or by a graphoepitaxial effect that guides their growth along nanogrooves or nanosteps along the surface. We characterized the crystallographic orientations and elemental composition of the nanowires using transmission electron microscopy and photoluminescence. The optoelectronic and electronic properties of the nanowires were studied by fabricating photodetectors and top-gate thin film transistors. These measurements showed that the guided ZnTe nanowires are p-type semiconductors and are photoconductive in the visible range. The guided growth of horizontal p-type nanowires opens up the possibility of parallel nanowire integration into functional systems with a variety of potential applications not available by other means.

Theory-driven design of hole-conducting transparent oxides

NASA Astrophysics Data System (ADS)

Trimarchi, G.; Peng, H.; Im, J.; Freeman, A. J.; Cloet, V.; Raw, A.; Poeppelmeier, K. R.; Biswas, K.; Lany, S.; Zunger, A.

2012-02-01

The design of p-type transparent conducting oxides (TCOs) aims at simultaneously achieving transparency and high hole concentration and hole conductivity in one compound. Such design principles (DPs) define a multi-objective optimization problem that is to be solved by searching a large set of compounds for optimum ones. Here, we screen a large set of ternary compounds, including Ag and Cu oxides and chalcogenides, by calculating via first-principles methods the design properties of each compound, in order to search for optimum p-type TCOs. We first select Ag3VO4 as a case study of the application of ab-initio methods to assess a compound as a candidate p-type TCO. We predict Ag3VO4 (i) to have a hole concentration of 10^14 cm-3 at room temperature, (ii) to be at the verge of transparency, and (iii) to have lower hole effective mass than the prototype p-type TCO CuAlO2. We then map the hole effective mass vs. the band gap in the selected compounds and determine those that best meet the DPs by having simultaneously minimum effective mass and a band gap large enough for transparency.

Solution-processed organic thermoelectric materials exhibiting doping-concentration-dependent polarity.

PubMed

Hwang, Sunbin; Potscavage, William J; Yang, Yu Seok; Park, In Seob; Matsushima, Toshinori; Adachi, Chihaya

2016-10-26

Recent progress in conducting polymer-based organic thermoelectric generators (OTEGs) has resulted in high performance due to high Seebeck coefficient, high electrical conductivity (σ), and low thermal conductivity obtained by chemically controlling the materials's redox levels. In addition to improving the properties of individual OTEGs to obtain high performance, the development of solution processes for the fabrication of OTEG modules is necessary to realize large thermoelectric voltage and low-cost mass production. However, the scarcity of good candidates for soluble organic n-type materials limits the use of π-leg module structures consisting of complementary elements of p- and n-type materials because of unbalanced transport coefficients that lead to power losses. In particular, the extremely low σ of n-type materials compared with that of p-type materials is a serious challenge. In this study, poly(pyridinium phenylene) (P(PymPh)) was tested as an n-type semiconductor in solution-processed OTEGs, and the carrier density was controlled by a solution-based chemical doping process using the dopant sodium naphthalenide, a well-known reductant. The electronic structures and doping mechanism of P(PymPh) were explored based on the changes in UV-Vis-IR absorption, ultraviolet photoelectron, and X-ray photoelectron spectra. By controlling the dopant concentration, we demonstrate a maximum n-type power factor of 0.81 μW m -1 K -2 with high σ, and at higher doping concentrations, a switch from n-type to p-type TE operation. This is one of the first cases of a switch in polarity just by increasing the concentration of the reductant and may open a new route for simplified fabrication of complementary organic layers.

Hydrochemistry of the Tumen River Estuary, Sea of Japan

NASA Astrophysics Data System (ADS)

Tishchenko, P. Ya.; Semkin, P. Yu.; Pavlova, G. Yu.; Tishchenko, P. P.; Lobanov, V. B.; Marjash, A. A.; Mikhailik, T. A.; Sagalaev, S. G.; Sergeev, A. F.; Tibenko, E. Yu.; Khodorenko, N. D.; Chichkin, R. V.; Shvetsova, M. G.; Shkirnikova, E. M.

2018-03-01

The hydrological and hydrochemical parameters of the Tumen River estuary were collected at 13 stations in May and October 2015. Vertical temperature, conductivity, dissolved oxygen, chlorophyll fluorescence, and turbidity profiles were obtained. Water was sampled from the surface and bottom layer. The water samples were analyzed for major ions, pH, salinity, concentrations of dissolved oxygen, major nutrients, dissolved organic carbon, humic matter, and δ18O and δD isotopes. This estuary is attributed to microtidal type with a flushing time of about 10 h. A phytoplakton bloom occurred in the top layer of the estuary. For surface horizons, the hydrochemical parameters show a linear correlation with salinity. In the bottom horizons, all these parameters, except for major ions and δ18O and δD isotopes, reveal substantial nonconservative behavior. The nonconservative behavior of the hydrochemical parameters in the bottom waters was mainly caused by degradation of the phytoplankton biomass at the water/sediment interface. Hypoxic conditions were established in the bottom waters of the estuary in May.

[Accident with biological material at the prehospital mobile care: reality for health and non-healthcare workers].

PubMed

Tipple, Anaclara Ferreira Veiga; Silva, Elisangelo Aparecido Costa; Teles, Sheila Araújo; Mendonça, Katiane Martins; Souza, Adenícia Custódia Silva E; Melo, Dulcelene Sousa

2013-01-01

Analytical transversal study that was conducted with the objectives of identifying the prevalence and characterizing the accidents with biological material among professionals in pre-hospital service (PHS) and comparing the risk behaviors adopted by healthcare and non-healthcare groups that can affect the occurrence and seriousness of such accidents. Data were obtained by questionnaire applied to all PHS workers in Goiânia-GO. The study revealed a high prevalence of accidents involving biological material which, although higher for the healthcare group, also affected the non-healthcare group. There were significant (p < 0.05) risk behaviors for these accidents in both groups: not using gloves, masks or eye protectors; inappropriate disposal of sharps; inadequate dress; re-capping of needles; and a lack of immunization against hepatitis B. The results underscore the importance of both groups in adhering to preventive measures, and further point to the need to structure and implement vigilance and control system for this type of accident.

Sociodemographic factors associated with self-reported exercise and physical activity behaviors and attitudes of South Australians: results of a population-based survey.

PubMed

Thomas, Susie; Halbert, Julie; Mackintosh, Shylie; Quinn, Stephen; Crotty, Maria

2012-03-01

To determine self-reported physical activity barriers, behaviors, and beliefs about exercise of a representative sample and to identify associated sociodemographic factors. Face-to-face interviews conducted between September and December 2008, using a random stratified sampling technique. Barriers injury and illness were associated with being older, single, and not engaged in full-time work; lack of time was associated with being married, younger, female, and working full-time; and lack of motivation and cost were associated with being younger than 65 years. Advancing age was significantly associated (p < .001) with reduced physical activity. Factors including age, education, marital status, and area of residence were all associated with preferences for environment to exercise in, while all age groups (74%) felt that walking was the most important type of exercise for older adults. A better understanding of these factors may improve uptake of and adherence to exercise programs across the ages.

Angular-dependent EDMR linewidth for spin-dependent space charge limited conduction in a polycrystalline pentacene

NASA Astrophysics Data System (ADS)

Fukuda, Kunito; Asakawa, Naoki

2017-08-01

Spin-dependent space charge limited carrier conduction in a Schottky barrier diode using polycrystalline p-type π-conjugated molecular pentacene is explored using multiple-frequency electrically detected magnetic resonance (EDMR) spectroscopy with a variable-angle configuration. The measured EDMR spectra are decomposed into two components derived respectively from mobile and trapped positive polarons. The linewidth of the EDMR signal for the trapped polarons increases with increasing resonance magnetic field for an in-plane configuration where the normal vector of the device substrate is perpendicular to the resonance magnetic field, while it is independent of the field for an out-of-plane configuration. This difference is consistent with the pentacene arrangement on the device substrate, where pentacene molecules exhibit a uniaxial orientation on the out-of-substrate plane. By contrast, the mobile polarons do not show anisotropic behavior with respect to the resonance magnetic field, indicating that the anisotropic effect is averaged out owing to carrier motion. These results suggest that the orientational arrangements of polycrystalline pentacene molecules in a nano thin film play a crucial role in spin-dependent electrical conduction.

[Development and Effects of a Drinking Prevention Program for Preschool Children].

PubMed

Kim, Younkyoung; Lee, Chong Mi; Park, Jong

2016-04-01

The purpose of this study was to identify the effects of the program to promote drinking knowledge, attitudes, and coping behavior in preschool children. A quasi-experimental with non-equivalent control group pretest-posttest design was conducted. The participants were 123 five year old children from G city. They were assigned to the experimental group (n=77) or the control group (n=46). A pretest and posttest were conducted to measure main variables. For the experimental group, the drinking prevention program was given for 6 weeks. Data were analyzed using χ²-test, t-test, and ANCOVA. After the intervention, preschool children in the experimental group reported significant differences in drinking knowledge (F=9.25, p=.003), drinking attitudes (F=19.57, p<.001), and coping behavior (F=16.38, p<.001) compared to preschool children in the control group. The results of this study indicate that a drinking prevention program for preschool children is effective in increasing drinking knowledge, attitudes, and coping behavior. This drinking prevention program is recommended as an effective intervention for preschool age children to postpone an early introduction to drinking.

Crystal Structure and Transport Properties of Oxygen-Deficient Perovskite Sr 0.9Y 0.1CoO 3-δ

DOE PAGES

Yang, Tianrang; Mattick, Victoria F.; Chen, Yan; ...

2018-01-29

The present work reports a systematic study on temperature-dependent local crystal structure, oxygen stoichiometry, and electrical/electrochemical properties of an oxygen-deficient Sr 0.9Y 0.1CoO 3-δ (SYC10) perovskite using variable-temperature neutron diffraction (VTND), thermal gravimetric analysis, and electrical/electrochemical methods, respectively. The VTND reveals that the crystal symmetry of SYC10 remains P4/mmm tetragonal up to 900 °C. The tetragonal symmetry reflects the net effects of temperature and oxygen stoichiometry on crystal symmetry. The observed p-type electronic conductivity behavior originates from the charge-ordering between the two distinctive Co-sites. The partial oxide-ion conductivity and diffusivity obtained from oxygen permeation measurements are 2.3 × 10 –2more » S cm –1 and 7.98 × 10–8 cm 2/s at 800 °C in air, respectively. The electrochemical oxygen reduction reaction kinetics of the SYC10 cathode is primarily limited by the charge-transfer process at low temperatures (600–650 °C) and oxide-ion migration from the cathode into the electrolyte at high temperatures (700–800 °C).« less

Crystal Structure and Transport Properties of Oxygen-Deficient Perovskite Sr 0.9Y 0.1CoO 3-δ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Tianrang; Mattick, Victoria F.; Chen, Yan

The present work reports a systematic study on temperature-dependent local crystal structure, oxygen stoichiometry, and electrical/electrochemical properties of an oxygen-deficient Sr 0.9Y 0.1CoO 3-δ (SYC10) perovskite using variable-temperature neutron diffraction (VTND), thermal gravimetric analysis, and electrical/electrochemical methods, respectively. The VTND reveals that the crystal symmetry of SYC10 remains P4/mmm tetragonal up to 900 °C. The tetragonal symmetry reflects the net effects of temperature and oxygen stoichiometry on crystal symmetry. The observed p-type electronic conductivity behavior originates from the charge-ordering between the two distinctive Co-sites. The partial oxide-ion conductivity and diffusivity obtained from oxygen permeation measurements are 2.3 × 10 –2more » S cm –1 and 7.98 × 10–8 cm 2/s at 800 °C in air, respectively. The electrochemical oxygen reduction reaction kinetics of the SYC10 cathode is primarily limited by the charge-transfer process at low temperatures (600–650 °C) and oxide-ion migration from the cathode into the electrolyte at high temperatures (700–800 °C).« less

Increased p-type conductivity through use of an indium surfactant in the growth of Mg-doped GaN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kyle, Erin C. H., E-mail: erinkyle@engineering.ucsb.edu; Kaun, Stephen W.; Young, Erin C.

2015-06-01

We have examined the effect of an indium surfactant on the growth of p-type GaN by ammonia-based molecular beam epitaxy. p-type GaN was grown at temperatures ranging from 700 to 780 °C with and without an indium surfactant. The Mg concentration in all films in this study was 4.5–6 × 10{sup 19} cm{sup −3} as measured by secondary ion mass spectroscopy. All p-type GaN films grown with an indium surfactant had higher p-type conductivities and higher hole concentrations than similar films grown without an indium surfactant. The lowest p-type GaN room temperature resistivity was 0.59 Ω-cm, and the highest room temperature carrier concentration wasmore » 1.6 × 10{sup 18} cm{sup −3}. Fits of the temperature-dependent carrier concentration data showed a one to two order of magnitude lower unintentional compensating defect concentration in samples grown with the indium surfactant. Samples grown at higher temperature had a lower active acceptor concentration. Improvements in band-edge luminescence were seen by cathodoluminescence for samples grown with the indium surfactant, confirming the trends seen in the Hall data.« less

Differences in substance-related risk behavior between dual and triple diagnosed severely mentally ill adults

PubMed Central

Hampton, Michelle DeCoux; Chafetz, Linda; Portillo, Carmen

2011-01-01

Objectives The purpose of this study was to determine if differences exist between adults with dual and triple diagnoses with regard to substance-related risk behaviors. Methods This secondary analysis was a cross-sectional study. There were 252 subjects with dual and triple diagnoses recruited from residential crisis programs in San Francisco. Using descriptive and logistic regression analyses, subjects in the two groups were compared with regard to demographic data, types of substances, and routes of administration used in the previous 30 days to determine risk for exposure and/or transmission of HIV/HCV. Results When compared to the dual diagnosis group, subjects with triple diagnoses were four times more likely to have engaged in IDU (p=.001) and 2.6 times more likely to use amphetamines (p=.05). They also reported using more types of substances over the lifetime (p<.0001). But with regard to other risk behaviors such as alcohol use to intoxication and cocaine/crack use, there were no significant differences. Conclusion Though many substance-related risk behaviors occurred in both groups, adults with triple diagnoses were more likely to engage in IDU, amphetamine use, and to use more types of substances over the lifetime. This information has the potential to inform interventions that might prevent/reduce substance-related risk in this population. PMID:22582086

Conductivity percolation in loosely compacted microcrystalline cellulose: An in situ study by dielectric spectroscopy during densification.

PubMed

Nilsson, Martin; Frenning, Göran; Gråsjö, Johan; Alderborn, Göran; Strømme, Maria

2006-10-19

The present study aims at contributing to a complete understanding of the water-induced ionic charge transport in cellulose. The behavior of this transport in loosely compacted microcrystalline cellulose (MCC) powder was investigated as a function of density utilizing a new type of measurement setup, allowing for dielectric spectroscopy measurement in situ during compaction. The ionic conductivity in MCC was found to increase with increasing density until a leveling-out was observed for densities above approximately 0.7 g/cm3. Further, it was shown that the ionic conductivity vs density followed a percolation type behavior signifying the percolation of conductive paths in a 3D conducting network. The density percolation threshold was found to be between approximately 0.2 and 0.4 g/cm3, depending strongly on the cellulose moisture content. The observed percolation behavior was attributed to the forming of interparticulate bonds in the MCC and the percolation threshold dependence on moisture was linked to the moisture dependence of particle rearrangement and plastic deformation in MCC during compaction. The obtained results add to the understanding of the density-dependent water-induced ionic transport in cellulose showing that, at given moisture content, the two major parameters determining the magnitude of the conductivity are the connectedness of the interparticluate bonds and the connectedness of pores with a diameter in the 5-20 nm size range. At densities between approximately 0.7 and 1.2 g/cm3 both the bond and the pore networks have percolated, facilitating charge transport through the MCC compact.

High School Sports Involvement Diminishes the Association Between Childhood Conduct Disorder and Adult Antisocial Behavior

PubMed Central

Samek, Diana R.; Elkins, Irene J.; Keyes, Margaret A.; Iacono, William G.; McGue, Matt

2015-01-01

Purpose Life course–persistent antisocial behavior manifests as a display of aggressive and antisocial behavior beginning in childhood (conduct disorder [CD]) and lasting through adulthood (adult antisocial personality disorder). This study aimed to build on prior research by evaluating whether involvement in high school sports helped attenuate the association between CD and subsequent adult antisocial behavior (AAB). Methods A prospective sample of 967 male and female adolescents (56% adopted) was used. Structured interviews were used to assess CD (symptoms before the age of 15 years), involvement in sports during high school, and past-year adult antisocial personality disorder symptoms in young adulthood (M age = 22.4 years). Results As expected, the association between CD and AAB was significantly less for those involved in sports (β = .28; p < .001) compared with those not involved in sports (β = .49; p < .001), χ2(1) = 4.13; p = .04. This difference remained after including known covariates of antisocial behavior in the model (age, gender, adoption status), and results were consistent across males and females. Involvement in other extracurricular activities (e.g., student government, plays, clubs) did not significantly moderate the relationship between CD and AAB. Conclusions Although selection effects were evident (those with more CD symptoms were less likely to be involved in sports), findings nevertheless suggest high school sports involvement may be a notable factor related to disrupting persistent antisocial behavior beginning in childhood and adolescence and lasting through young adulthood. Implications are discussed. PMID:25937472

Heat transport in an anharmonic crystal

NASA Astrophysics Data System (ADS)

Acharya, Shiladitya; Mukherjee, Krishnendu

2018-04-01

We study transport of heat in an ordered, anharmonic crystal in the form of slab geometry in three dimensions. Apart from attaching baths of Langevin type to two extreme surfaces, we also attach baths of same type to the intermediate surfaces of the slab. Since the crystal is uninsulated, it exchanges energy with the intermediate heat baths. We find that both Fourier’s law of heat conduction and the Newton’s law of cooling hold to leading order in anharmonic coupling. The leading behavior of the temperature profile is exponentially falling from high to low temperature surface of the slab. As the anharmonicity increases, profiles fall more below the harmonic one in the log plot. In the thermodynamic limit thermal conductivity remains independent of the environment temperature and its leading order anharmonic contribution is linearly proportional to the temperature change between the two extreme surfaces of the slab. A fast crossover from one-dimensional (1D) to three-dimensional (3D) behavior of the thermal conductivity is observed in the system.

Genome-wide interaction study of smoking behavior and non-small cell lung cancer risk in Caucasian population.

PubMed

Li, Yafang; Xiao, Xiangjun; Han, Younghun; Gorlova, Olga; Qian, David; Leighl, Natasha; Johansen, Jakob S; Barnett, Matt; Chen, Chu; Goodman, Gary; Cox, Angela; Taylor, Fiona; Woll, Penella; Wichmann, H-Erich; Manz, Judith; Muley, Thomas; Risch, Angela; Rosenberger, Albert; Arnold, Susanne M; Haura, Eric B; Bolca, Ciprian; Holcatova, Ivana; Janout, Vladimir; Kontic, Milica; Lissowska, Jolanta; Mukeria, Anush; Ognjanovic, Simona; Orlowski, Tadeusz M; Scelo, Ghislaine; Swiatkowska, Beata; Zaridze, David; Bakke, Per; Skaug, Vidar; Zienolddiny, Shanbeh; Duell, Eric J; Butler, Lesley M; Houlston, Richard; Soler Artigas, María; Grankvist, Kjell; Johansson, Mikael; Shepherd, Frances A; Marcus, Michael W; Brunnström, Hans; Manjer, Jonas; Melander, Olle; Muller, David C; Overvad, Kim; Trichopoulou, Antonia; Tumino, Rosario; Liu, Geoffrey; Bojesen, Stig E; Wu, Xifeng; Marchand, Loic Le; Albanes, Demetrios; Bickeböller, Heike; Aldrich, Melinda C; Bush, William S; Tardon, Adonina; Rennert, Gad; Teare, M Dawn; Field, John K; Kiemeney, Lambertus A; Lazarus, Philip; Haugen, Aage; Lam, Stephen; Schabath, Matthew B; Andrew, Angeline S; Bertazzi, Pier Alberto; Pesatori, Angela C; Christiani, David C; Caporaso, Neil; Johansson, Mattias; McKay, James D; Brennan, Paul; Hung, Rayjean J; Amos, Christopher I

2018-03-08

Non-small cell lung cancer is the most common type of lung cancer. Both environmental and genetic risk factors contribute to lung carcinogenesis. We conducted a genome-wide interaction analysis between single nucleotide polymorphisms (SNPs) and smoking status (never- versus ever-smokers) in a European-descent population. We adopted a two-step analysis strategy in the discovery stage: we first conducted a case-only interaction analysis to assess the relationship between SNPs and smoking behavior using 13336 non-small cell lung cancer cases. Candidate SNPs with P-value <0.001 were further analyzed using a standard case-control interaction analysis including 13970 controls. The significant SNPs with P-value <3.5 × 10-5 (correcting for multiple tests) from the case-control analysis in the discovery stage were further validated using an independent replication dataset comprising 5377 controls and 3054 non-small cell lung cancer cases. We further stratified the analysis by histological subtypes. Two novel SNPs, rs6441286 and rs17723637, were identified for overall lung cancer risk. The interaction odds ratio and meta-analysis P-value for these two SNPs were 1.24 with 6.96 × 10-7 and 1.37 with 3.49 × 10-7, respectively. In addition, interaction of smoking with rs4751674 was identified in squamous cell lung carcinoma with an odds ratio of 0.58 and P-value of 8.12 × 10-7. This study is by far the largest genome-wide SNP-smoking interaction analysis reported for lung cancer. The three identified novel SNPs provide potential candidate biomarkers for lung cancer risk screening and intervention. The results from our study reinforce that gene-smoking interactions play important roles in the etiology of lung cancer and account for part of the missing heritability of this disease.

IVABRADINE LOADED SOLID LIPID MICROPARTICLES: FORMULATION, CHARACTERIZATION AND OPTIMIZATION BY CENTRAL COMPOSITE ROTATABLE DESIGN.

PubMed

Hanif, Muhammad; Khan, Hafeez Ullah; Afzal, Samina; Sher, Muhammad

2017-01-01

The current research focused on improvement of oral bioavailability and decrease in dosing frequency of ivabradine (Iva) in order to enhance patient compliance by formulating novel sustained release Iva loaded solid lipid microparticles (SLMs) with the help of melt emulsification technique. SLMs formulations were designed with the help of three level central composite rotatable design (CCRD) to study the impact of independent variables like lipid concentration, surfactant concentration and stirring speed on responses - percentage yield (Y,) and entrapment efficiency (Y2). Compatibility between the drug and bees wax (BW) was checked by conducting Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRD). SLMs were further evaluated for rheological behavior, zeta potential, particle size and for morphology by scanning'electron microscope (SEM). The release of drug from SLMs was conducted by USP type-Il apparatus at pH 1.2, pH 6.8 and data were analyzed by different kinetic models like zero order, first order, Higuchi model, Korsmeyer-Peppas and Hixon-Crowell models. The rheo- logical studies approved the good flow behavior of SLMs and spherical smooth surface of SLMs was observed from SEM. DSC, FTIR and XRD studies concluded the lack of any possible interaction between formulation components. The size-of SLMs ranged from 300 to 500 pm and zeta potential study showed the presence of higher negative charge (-30 to -52 mV). Response Y, varied from 53 to 90% and response Y2 ranged from 29 to 78% indicating the effect of formulation variables. The obtained outcomes were analyzed by second order polynomial equation and suggested quadratic model was also validated. SLMs released Iva from 54 to 90% at pH 6.8 and was significantly (p 0.05) affected by BW concentration. The release mechanism followed the zero order and Korsmeyer-Peppas (n 0.85) kinetic models suggesting slow erosion along with diffusion mechanism for Iva release.

Crystal structures, Hirshfeld surface analysis, thermal behavior and dielectric properties of a new organic-inorganic hybrid [C6H10(NH3)2]Cu2Cl8

NASA Astrophysics Data System (ADS)

Salah, Najet; Hamdi, Besma; Bouzidia, Nabaa; Salah, Abdelhamid Ben

2017-12-01

A novel organic-inorganic hybrid sample [C6H10(NH3)2]Cu2Cl8 has been prepared under mild hydrothermal conditions and characterized by single crystal X-ray diffraction, Hirshfeld surface analysis, FT-IR,NMR and UV-Vis spectroscopies, differential scanning calorimetric and dielectric measurement. It is crystallized in the monoclinic system with P21/c space group. The cohesion and stabilization of the structure are provided by the hydrogen bond interactions, (Nsbnd H⋯Cl and Csbnd H⋯Cl), between [C6H10(NH3)2]2+ cation and [Cu2Cl8]2- anion. The Hirschfeld surface analysis has been performed to explore the behavior of these weak interactions. The presence of different functional groups and the nature of their vibrations were identified by FT-IR and Solid state NMR. The thermal study revealed that this compound undergoes two structural phase transitions around 353 and 376 K. Electrical measurements of our compounds have been investigated using complex impedance spectroscopy (CIS) in the frequency and temperature range 331-399 K and 200 Hz-5 MHz, respectively. The AC conductivity is explained using the correlated barrier hopping model (CBH) conduction mechanism. The nature of DC conductivity variation suggests Arrhenius type of electrical conductivity. A relationship between crystal structure and ionic conductivity was established and discussed. Finally, the real and imaginary parts of the permittivity constant are analyzed with the Cole-Cole formalism and the optical spectra indicate that the compound has a direct band gap (3.14 eV) due to direct transition. The wide band gap is due to low defect concentration in the grown crystal, which is more useful for the laser/optical applications.

Analysis of the technology acceptance model in examining hospital nurses' behavioral intentions toward the use of bar code medication administration.

PubMed

Song, Lunar; Park, Byeonghwa; Oh, Kyeung Mi

2015-04-01

Serious medication errors continue to exist in hospitals, even though there is technology that could potentially eliminate them such as bar code medication administration. Little is known about the degree to which the culture of patient safety is associated with behavioral intention to use bar code medication administration. Based on the Technology Acceptance Model, this study evaluated the relationships among patient safety culture and perceived usefulness and perceived ease of use, and behavioral intention to use bar code medication administration technology among nurses in hospitals. Cross-sectional surveys with a convenience sample of 163 nurses using bar code medication administration were conducted. Feedback and communication about errors had a positive impact in predicting perceived usefulness (β=.26, P<.01) and perceived ease of use (β=.22, P<.05). In a multiple regression model predicting for behavioral intention, age had a negative impact (β=-.17, P<.05); however, teamwork within hospital units (β=.20, P<.05) and perceived usefulness (β=.35, P<.01) both had a positive impact on behavioral intention. The overall bar code medication administration behavioral intention model explained 24% (P<.001) of the variance. Identified factors influencing bar code medication administration behavioral intention can help inform hospitals to develop tailored interventions for RNs to reduce medication administration errors and increase patient safety by using this technology.

Low temperature thermoelectric properties of p-type doped single-crystalline SnSe

NASA Astrophysics Data System (ADS)

Wang, Si; Hui, Si; Peng, Kunling; Bailey, Trevor P.; Liu, Wei; Yan, Yonggao; Zhou, Xiaoyuan; Tang, Xinfeng; Uher, Ctirad

2018-04-01

SnSe single crystals have been widely studied lately as a result of their record high ZT and controversial low thermal conductivity. Much research has focused on the high-temperature properties of single crystals and polycrystalline SnSe, but few studies were carried out on the low-temperature properties of doped single-crystalline SnSe. To study the mechanism of the charge carrier and phonon scattering, and to eliminate the ambiguity of the high temperature thermal conductivity measurement, we performed low temperature transport characterization of Na-doped and Ag-doped single-crystalline SnSe by a longitudinal steady-state technique. The electronic transport property measurements suggest that Na is a more efficient p-type dopant in SnSe than Ag. In the thermal conductivity data, we observe pronounced dielectric peak around 10 K with magnitude dependent on the doping level. In the p-type doped samples, we found that our room temperature lattice thermal conductivities (>1.74 W m-1 K-1) are in general higher than those previously reported. Based on these findings, our study implies that the lattice thermal conductivity values of doped and pure single-crystalline SnSe were underestimated.

Copper interstitial recombination centers in Cu3N

NASA Astrophysics Data System (ADS)

Yee, Ye Sheng; Inoue, Hisashi; Hultqvist, Adam; Hanifi, David; Salleo, Alberto; Magyari-Köpe, Blanka; Nishi, Yoshio; Bent, Stacey F.; Clemens, Bruce M.

2018-06-01

We present a comprehensive study of the earth-abundant semiconductor Cu3N as a potential solar energy conversion material, using density functional theory and experimental methods. Density functional theory indicates that among the dominant intrinsic point defects, copper vacancies VCu have shallow defect levels while copper interstitials Cui behave as deep potential wells in the conduction band, which mediate Shockley-Read-Hall recombination. The existence of Cui defects has been experimentally verified using photothermal deflection spectroscopy. A Cu3N /ZnS heterojunction diode with good current-voltage rectification behavior has been demonstrated experimentally, but no photocurrent is generated under illumination. The absence of photocurrent can be explained by a large concentration of Cui recombination centers capturing electrons in p -type Cu3N .

Thermoelectric transport in surface- and antimony-doped bismuth telluride nanoplates

NASA Astrophysics Data System (ADS)

Pettes, Michael Thompson; Kim, Jaehyun; Wu, Wei; Bustillo, Karen C.; Shi, Li

2016-10-01

We report the in-plane thermoelectric properties of suspended (Bi1-xSbx)2Te3 nanoplates with x ranging from 0.07 to 0.95 and thicknesses ranging from 9 to 42 nm. The results presented here reveal a trend of increasing p-type behavior with increasing antimony concentration, and a maximum Seebeck coefficient and thermoelectric figure of merit at x ˜ 0.5. We additionally tuned extrinsic doping of the surface using a tetrafluoro-tetracyanoquinodimethane (F4-TCNQ) coating. The lattice thermal conductivity is found to be below that for undoped ultrathin Bi2Te3 nanoplates of comparable thickness and in the range of 0.2-0.7 W m-1 K-1 at room temperature.

Determinants of Consistent Condom Use among College Students in China: Application of the Information-Motivation-Behavior Skills (IMB) Model

PubMed Central

Liu, Zhihao; Wei, Pingmin; Huang, Minghao; Liu, Yuan bao; Li, Lucy; Gong, Xiao; Chen, Juan; Li, Xiaoning

2014-01-01

Background Due to the increase incidents of premarital sex and the lack of reproductive health services, college students are at high risk of HIV/AIDS infections in China. This study was designed to examine the predictors of consistency of condom use among college students based on the Information-Motivation-Behavioral Skills (IMB) model and to describe the relationships between the model constructs. Methods A cross-sectional study was conducted to assess HIV/AIDS related information, motivation, behavioral skills and preventive behavior among college students in five colleges and universities in Nanjing, China. An anonymous questionnaire survey was conducted for data collection, and the structural equation model (SEM) was used to assess the IMB model. Results A total of 3183 participants completed this study. The average age was 19.90 years (SD = 1.43, range 16 to 25). 342 (10.7%) participants of them reported having had premarital sex, among whom 30.7% reported having had a consistent condom use, 13.7% with the experience of abortion (including the participants whose sex partner has the same experience), 32.7% of participants had experience of multiple sex partners. The final IMB model provided acceptable fit to the data (CFI = 0.992, RMSEA = 0.028). Preventive behavior was significantly predicted by behavioral skills (β = 0.754, P<0.001). Information (β = 0.138, P<0.001) and motivation (β = 0.363, P<0.001) were indirectly affected preventive behavior, and was mediated through behavioral skills. Conclusions The results of the study demonstrate the utility of the IMB model for consistent condom use among college students in China. The main influencing factor of preventive behavior among college students is behavioral skills. Both information and motivation could affect preventive behavior through behavioral skills. Further research could develop preventive interventions based on the IMB model to promote consistent condom use among college students in China. PMID:25265390

Determinants of consistent condom use among college students in China: application of the information-motivation-behavior skills (IMB) model.

PubMed

Liu, Zhihao; Wei, Pingmin; Huang, Minghao; Liu, Yuan bao; Li, Lucy; Gong, Xiao; Chen, Juan; Li, Xiaoning

2014-01-01

Due to the increase incidents of premarital sex and the lack of reproductive health services, college students are at high risk of HIV/AIDS infections in China. This study was designed to examine the predictors of consistency of condom use among college students based on the Information-Motivation-Behavioral Skills (IMB) model and to describe the relationships between the model constructs. A cross-sectional study was conducted to assess HIV/AIDS related information, motivation, behavioral skills and preventive behavior among college students in five colleges and universities in Nanjing, China. An anonymous questionnaire survey was conducted for data collection, and the structural equation model (SEM) was used to assess the IMB model. A total of 3183 participants completed this study. The average age was 19.90 years (SD = 1.43, range 16 to 25). 342 (10.7%) participants of them reported having had premarital sex, among whom 30.7% reported having had a consistent condom use, 13.7% with the experience of abortion (including the participants whose sex partner has the same experience), 32.7% of participants had experience of multiple sex partners. The final IMB model provided acceptable fit to the data (CFI = 0.992, RMSEA = 0.028). Preventive behavior was significantly predicted by behavioral skills (β = 0.754, P<0.001). Information (β = 0.138, P<0.001) and motivation (β = 0.363, P<0.001) were indirectly affected preventive behavior, and was mediated through behavioral skills. The results of the study demonstrate the utility of the IMB model for consistent condom use among college students in China. The main influencing factor of preventive behavior among college students is behavioral skills. Both information and motivation could affect preventive behavior through behavioral skills. Further research could develop preventive interventions based on the IMB model to promote consistent condom use among college students in China.

Factors associated with bystander behaviors of Korean youth in school bullying situations: A cross-sectional study.

PubMed

Yang, Seung Ae; Kim, Dong Hee

2017-08-01

The behaviors of bystanders can have important effects on their peers. The aim of this study was to identify psychosocial and contextual factors associated with 3 types of bystander behavior (bully followers, outsiders, and defenders of victims) among Korean youth. A descriptive and cross-sectional study was conducted among 416 7th and 8th-grade students from 1 middle school in Korea. The Rosenberg Self Esteem Scale, the Korean version of the Social Problem-Solving Inventory, and measurements of relationships with friends and teachers, empathy, concerns about being bullied, attitudes toward bullying, and bystander behaviors were all used in the assessment. Empathy, relationship of teachers, attitudes toward bullying, and concerns about being bullied were significantly associated with all 3 types of bystanders' behaviors. Although, self-esteem, social problem solving ability were significantly associated with just defender of victim behaviors. These results suggest that several significant factors to cultivate constructive bystander behaviors should be considered to develop effective antibullying intervention.

Aggression in low functioning children and adolescents with autistic disorder.

PubMed

Bronsard, Guillaume; Botbol, Michel; Tordjman, Sylvie

2010-12-21

Parents, caregivers and mental health professionals have often reported violence and aggression in children or adolescents with autistic disorder. However, most of these observations derived from anecdotal reports, and studies on frequency and characterization of aggression in autism remain limited. Our objective was to better characterize and understand the different types of aggressive behaviors displayed by a large group of individuals with autism in different observational situations. The study was conducted on 74 children and adolescents with autism and 115 typically developing control individuals matched for sex, age and pubertal stage. Other-Injurious Behaviors (OIB) were assessed in three observational situations (parents at home, two caregivers at day-care, a nurse and a child psychiatrist during blood drawing) using validated scales. The frequency of OIB was significantly higher in individuals with autism compared to typically developing control individuals during the blood drawing (23% vs. 0%, P<0 .01). The parents observed significantly less OIB in their children than caregivers (34% vs. 58%, P<0.05). In addition, the most frequent concurrent behaviors occurring just before the appearance of OIB in individuals with autism were anxiety-related behaviors and excitation according to the parental as well as the caregiver observation. The results suggest that in a stressful situation, such as the blood drawing, individuals with autism release their stress through behaviors such as OIB, whereas typically developing individuals regulate and express their stress through cognitive skills such as mental coping strategies, symbolization skills with representation and anticipation of the stressful situation, social interaction and verbal or non-verbal communication. The findings underline also the key role of the environment in assessing OIB and developing therapeutic perspectives, with an individual who modulates his/her behavior according to the environment, and an environment that perceives this behavior and reacts to it with different tolerance thresholds according to the observers.

Aggression in Low Functioning Children and Adolescents with Autistic Disorder

PubMed Central

Bronsard, Guillaume; Botbol, Michel; Tordjman, Sylvie

2010-01-01

Background Parents, caregivers and mental health professionals have often reported violence and aggression in children or adolescents with autistic disorder. However, most of these observations derived from anecdotal reports, and studies on frequency and characterization of aggression in autism remain limited. Our objective was to better characterize and understand the different types of aggressive behaviors displayed by a large group of individuals with autism in different observational situations. Methodology/Findings The study was conducted on 74 children and adolescents with autism and 115 typically developing control individuals matched for sex, age and pubertal stage. Other-Injurious Behaviors (OIB) were assessed in three observational situations (parents at home, two caregivers at day-care, a nurse and a child psychiatrist during blood drawing) using validated scales. The frequency of OIB was significantly higher in individuals with autism compared to typically developing control individuals during the blood drawing (23% vs. 0%, P<0 .01). The parents observed significantly less OIB in their children than caregivers (34% vs. 58%, P<0.05). In addition, the most frequent concurrent behaviors occurring just before the appearance of OIB in individuals with autism were anxiety-related behaviors and excitation according to the parental as well as the caregiver observation. Conclusions/Significance The results suggest that in a stressful situation, such as the blood drawing, individuals with autism release their stress through behaviors such as OIB, whereas typically developing individuals regulate and express their stress through cognitive skills such as mental coping strategies, symbolization skills with representation and anticipation of the stressful situation, social interaction and verbal or non-verbal communication. The findings underline also the key role of the environment in assessing OIB and developing therapeutic perspectives, with an individual who modulates his/her behavior according to the environment, and an environment that perceives this behavior and reacts to it with different tolerance thresholds according to the observers. PMID:21200441

Secrecy From Parents and Type 1 Diabetes Management in Late Adolescence

PubMed Central

Wiebe, Deborah J.; Van Bogart, Karina; Turner, Sara L.; Tucker, Christy; Butner, Jonathan E.; Berg, Cynthia A.

2015-01-01

Objectives This study examined (a) associations of parent–adolescent relationship characteristics and adolescent problem behavior with late adolescents’ secrecy from parents about type 1 diabetes management, and (b) whether secrecy was associated with diabetes and psychological outcomes independently of these factors. Methods Adolescents (N = 247, Mage = 17.76 years) completed survey measures of diabetes-related secrecy from parents, disclosure, parental acceptance, parental knowledge, and conduct problems. Mothers and adolescents reported on adolescent adherence to diabetes regimens and adolescents reported their depressive symptoms. Glycemic control was obtained from HbA1c test kits. Results Adolescent-reported disclosure to parents was uniquely negatively associated with secrecy from parents. Controlling for relationship variables, conduct problems, and sociodemographic and illness-related variables, secrecy from mothers was uniquely associated with poorer glycemic control and secrecy from both parents was associated with lower adherence. Conclusions Secrecy about type 1 diabetes management is uniquely associated with diabetes outcomes independent of other relationship characteristics and problem behaviors. PMID:26136405

Appearance-related teasing, body dissatisfaction, and disordered eating: A meta-analysis.

PubMed

Menzel, Jessie E; Schaefer, Lauren M; Burke, Natasha L; Mayhew, Laura L; Brannick, Michael T; Thompson, J Kevin

2010-09-01

A meta-analysis was conducted to determine the relationship between appearance and weight-based teasing and three outcome measures: body dissatisfaction, restrictive eating, and bulimic behaviors. Four meta-analyses were conducted. Fifty effect sizes (N=10,618) resulted in a moderate effect size of .39 for the relationship between weight teasing and body dissatisfaction; 24 effect sizes (N=7190) resulted in an effect size of .32 for the relationship between appearance teasing and body dissatisfaction; 20 effect sizes (N=4792) resulted in an effect size of .35 for the relationship between weight teasing and dietary restraint; and 22 effect sizes (N=5091) resulted in an effect size of .36 for the relationship between weight teasing and bulimic behaviors. Significant moderators that emerged were teasing measure type, publication type, study type, age group, and gender. The findings offer further support for the inclusion of strategies in body image and eating disorders' prevention and intervention programs that focus on handling negative, appearance-related commentary. Copyright © 2010 Elsevier Ltd. All rights reserved.

Pressure-induced structural transition in chalcopyrite ZnSiP 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhadram, Venkata S.; Krishna, Lakshmi; Toberer, Eric S.

The pressure-dependent phase behavior of semiconducting chalcopyrite ZnSiP 2 was studied up to 30 GPa using in situ X-ray diffraction and Raman spectroscopy in a diamond-anvil cell. A structural phase transition to the rock salt type structure was observed between 27 and 30 GPa, which is accompanied by soft phonon mode behavior and simultaneous loss of Raman signal and optical transmission through the sample. The high-pressure rock salt type phase possesses cationic disorder as evident from broad features in the X-ray diffraction patterns. The behavior of the low-frequency Raman modes during compression establishes a two-stage, order-disorder phase transition mechanism. Themore » phase transition is partially reversible, and the parent chalcopyrite structure coexists with an amorphous phase upon slow decompression to ambient conditions.« less

Control of conduction type in ferromagnetic (Zn,Sn,Mn)As2 thin films by changing Mn content and effect of annealing on thin films with n-type conduction

NASA Astrophysics Data System (ADS)

Minamizawa, Yuto; Kitazawa, Tomohiro; Hidaka, Shiro; Toyota, Hideyuki; Nakamura, Shin-ichi; Uchitomi, Naotaka

2018-04-01

The conduction type in (Zn,Sn,Mn)As2 thin films grown by molecular beam epitaxy (MBE) on InP substrates was found to be controllable from p-type to n-type as a function of Mn content. n-type (Zn,Sn,Mn)As2 thin films were obtained by Mn doping of more than approximately 11 cat.%. It is likely that Mn interstitials (MnI) incorporated by excess Mn doping are located at tetrahedral hollow spaces surrounded by Zn and Sn cation atoms and four As atoms, which are expected to act as donors in (Zn,Sn,Mn)As2, resulting in n-type conduction. The effect of annealing on the structural, electrical and magnetic properties of n-type (Zn,Sn,Mn)As2 thin films was investigated as functions of annealing temperature and time. It was revealed that even if the annealing temperature is considerably higher than the growth temperature of 320 °C, the magnetic properties of the thin films remain stable. This suggests that a MnI complex surrounded by Zn and Sn atoms is thermally stable during high-temperature annealing. The n-type (Zn,Sn,Mn)As2 thin films may be suitable for application as n-type spin-polarized injectors.

Introduction of Interfacial Charges to Black Phosphorus for a Family of Planar Devices

NASA Astrophysics Data System (ADS)

Bao, Lihong; Wang, Guocai; Du, Shixuan; Pantelides, Sokrates; Gao, Hong-Jun

As a young member in the family of two dimensional materials, black phosphorus (BP) has attracted great attention since its discovery due to its high hole mobility and a sizable and tunable bandgap, which meets the basic requirements for logic circuits applications. Naturally, for realization of complementary logic operation, the challenge lies in how to control the conduction type in BP FETs, i.e., the dominant carrier types, holes (p-type) or electrons (n-type). However, the absence of reliable substitutional doping techniques makes this task a great challenge. Introducing interfacial charges into 2D materials has been proven to be a successfulway to control conduction. In this work, we, for the first time, demonstrate that capping a thin BP layer with a layer of cross-linked PMMA can modify the conductivity type of the BP by a surface charge transfer process, converting a BP layer dominated by hole conduction in the absence of an external electric field (p-type) to one dominated by electron conduction (n-type). Combining BP films capped by cross-linked PMMA with standard BP, a familyof planar devices can be created, including BP gated diodes and bidirectional recitifiers (rectification ratio >102) and BP logic inverter (gain¡«0.75) which are capable of performing current rectification, switching, and signal inversion operations. The device performance demonstrated here suggests a promising route for developing 2D-based electronics.

The characteristics of medical students' personality types and interpersonal needs.

PubMed

Hur, Yera; Cho, A-Ra; Kim, Sun

2013-12-01

Medical students' personality types and interpersonal needs must be considered. The purpose of this study was to examine the characteristics of personality types and interpersonal needs. A total of 171 students in Konyang University College of Medicine were examined using the Myers-Briggs Type Indicator (MBTI) and Fundamental Interpersonal Relations Orientation-Behavior (FIRO-B). The data were analyzed by frequency analysis, t-test, and one-sample proportion test. The proportion of the 4 pairs of MBTI dimensions were Extroversion (E)-Introversion (I) (53.2% vs. 46.8%), Sensing (S)-Intuition (N) (63.2% vs. 36.8%), Thinking (T)-Feeling (F) (59.7% vs. 40.4%), and Judging (J)-Perceiving (P) (56.1% vs. 43.9%). The predominant personality types were ISTJ (16.4%), ESTJ (14.0%), and ESFJ (10.5%). The level of interpersonal needs were medium rage that was inclusion (mean=8.1), control (mean=8.8), affection (mean=8.1), expressed behavior (mean=12.1), wanted behavior (mean=12.9), and overall interpersonal needs (mean=25.0). Of the basic social needs, males and females differed significantly with regard to control needs (p=0.028). Educational programs that take into account personality types and characteristics of interpersonal needs are crucial in providing effective medical education. Our results suggest that the characteristics of personality types and interpersonal needs should be considered in developing an interpersonal relations improvement program for medical students.

Comparison of the effects of intravenous premedication: Midazolam, Ketamine, and combination of both on reducing anxiety in pediatric patients before general anesthesia

PubMed Central

Sajedi, Parvin; Habibi, Bashir

2015-01-01

Objective: In some medical circumstances, pediatric patients may need premedication for transferring to the operating room. In these situations, using intravenous premedication is preferred. We assessed the efficacy and safety of intravenous midazolam, intravenous ketamine, and combination of both to reduce the anxiety and improve behavior in children undergoing general anesthesia. Methods: In a double-blind randomized clinical trial, 90 pediatric patients aged 6 months to 6 years with American Society of Anesthesiologist grade I or II were enrolled. Before anesthesia, children were randomly divided into three groups to receive intravenous midazolam 0.1 mg/kg, or intravenous ketamine 1 mg/kg, or combination of half doses of both. Behavior types and sedation scores were recorded before premedication, after premedication, before anesthesia, and after anesthesia in the postanesthesia care unit. Anesthesia time, recovery duration, blood pressure, and heart rate were also recorded. For comparing distribution of behavior types and sedation scores among three groups, we used Kruskal–Wallis test, and for comparing mean and standard deviation of blood pressure and heart rates, we used analysis of variance. Findings: After premedication, children's behavior was significantly better in the combination group (P < 0.001). After anesthesia, behavior type was same among three groups (P = 0.421). Sedation scores among three groups were also different after premedication and the combination group was significantly more sedated than the other two groups (P < 0.001). Conclusion: Combination of 0.05 mg/kg of intravenous midazolam and 0.5 mg/kg of intravenous ketamine as premedication produced more deep sedation and more desirable behavior in children compared with each midazolam 0.1 mg/kg or ketamine 1 mg/kg. PMID:26645024

Impact of peer nutrition education on dietary behaviors and health outcomes among Latinos: A systematic literature review

PubMed Central

Pérez-Escamilla, Rafael; Hromi-Fiedler, Amber; Vega-López, Sonia; Bermúdez-Millán, Angela; Segura-Pérez, Sofia

2009-01-01

Objective This systematic review assesses the impact of peer education/counseling on nutrition and health outcomes among Latinos, and identifies future research needs. Design A systematic literature search was conducted by: a) searching internet databases, b) conducting backward searches from reference lists of articles of interest, c) manually reviewing the archives of the Center for Eliminating Health Disparities among Latinos (CEHDL), d) searching the Journal of Nutrition Education and Behavior, and e) directly contacting researchers in the field. We reviewed 22 articles derived from experimental or quasi-experimental studies. Outcomes Type 2 diabetes behavioral and metabolic outcomes, breastfeeding, nutrition knowledge, attitudes and behaviors. Results Peer nutrition education has a positive influence on diabetes self-management, breastfeeding outcomes, as well as on general nutrition knowledge and dietary intake behaviors among Latinos. Conclusions and implications There is a need for longitudinal randomized trials testing the impact of peer nutrition education interventions grounded on goal setting and culturally appropriate behavioral change theories. Inclusion of reliable scales and the construct of acculturation is needed for further advancing the knowledge in this promising field. Operational research is also needed to identify the optimal peer educator characteristics, the type of training that they should receive, the client loads and dosage (i.e., frequency and amount of contact needed between needed peer educator and client), and the best educational approaches and delivery settings. PMID:18565462

Salivary oxytocin in adolescents with conduct problems and callous-unemotional traits.

PubMed

Levy, Tomer; Bloch, Yuval; Bar-Maisels, Meytal; Gat-Yablonski, Galia; Djalovski, Amir; Borodkin, Katy; Apter, Alan

2015-12-01

Callous-unemotional (CU) traits correlate with the severity and prognosis of conduct disorder in youth. The neuropeptide oxytocin (OT) has been linked to prosocial behaviors, including empathy and collaboration with others. This study discusses a possible role for OT in the biology of delinquent behavior. We hypothesized that in delinquent youth OT secretion will correlate with the severity of conduct problems and specifically with the level of CU traits. The study group included 67 male adolescents (mean age 16.2 years) undergoing residential treatment, previously assessed by an open clinical interview and history for the psychiatric diagnosis. Staff based Inventory of Callous-Unemotional traits for psychopathy and Strength and Difficulties Questionnaire were administered, and patients' medical and social personal files were systematically coded for previous history of antisocial acts using the Brown-Goodwin Questionnaire. Salivary OT was assayed by ELISA. Salivary OT levels were inversely correlated with conduct problems severity on Strength and Difficulties Questionnaire (r = -0.27; p ≤ 0.01). Recorded history of antisocial acts did not correlate with current OT levels. Odds ratio (OR) for significant CU traits among subjects with conduct problems was increased in low-OT (OR = 14, p ≤ 0.05) but not in high-OT subjects (OR = 6, p ≥ 0.05). Children with conduct problems and low levels of salivary OT are at risk for significant CU traits. These results suggest a possible role for salivary OT as a biomarker for CU traits and conduct problems severity.

Ultrasensitive gas detection of large-area boron-doped graphene

DOE PAGES

Lv, Ruitao; Chen, Gugang; Li, Qing; ...

2015-11-02

Heteroatom doping is an efficient way to modify the chemical and electronic properties of graphene. In particular, boron doping is expected to induce a p-type conducting behavior to pristine (undoped) graphene which could lead to diverse applications. But, the experimental progress on atomic scale visualization and sensing properties of large-area boron-doped graphene (BG) sheets is still very scarce. This work describes the controlled growth of centimeter size, high-crystallinity BG sheets. Scanning tunneling microscopy and spectroscopy are used to visualize the atomic structure and the local density of states around boron dopants. We confirmed that BG behaves as a p-type conductormore » and a unique croissant-like feature is frequently observed within the BG lattice, which is caused by the presence of B-C trimmers embedded within the hexagonal lattice. Interestingly, it is demonstrated for the first time that BG exhibits unique sensing capabilities when detecting toxic gases, such as NO 2 and NH 3 , being able to detect extremely low concentrations (e.g. parts per trillion, parts per billion). Our work envisions that other attractive applications could now be explored based on as-synthesized BG.« less

Family involvement is helpful and harmful to patients’ self-care and glycemic control

PubMed Central

Mayberry, Lindsay Satterwhite; Osborn, Chandra Y.

2014-01-01

Objective We assessed the relationships between supportive and obstructive family behaviors and patients’ diabetes self-care activities and HbA1C, and potential interaction effects and differences by demographic characteristics. Methods In a cross-sectional study, 192 adults with type 2 diabetes completed the Diabetes Family Behavior Checklist-II, the Summary of Diabetes Self-Care Activities, and a glycemic control (HbA1C) test. Results Participants reported similar rates of supportive and obstructive behaviors that were positively correlated (rho=0.61, p<.001). In adjusted analyses, supportive family behaviors were associated with adherence to different self-care behaviors (β=0.20–0.50, p<.05), whereas obstructive family behaviors were associated with less adherence to self-care behaviors (β=−0.28–−0.39, p<.01) and worse HbA1C (β=0.18, p<.05). Supportive behaviors protected against the detrimental effect of obstructive behaviors on HbA1C (interaction β=−0.22, p<.001). Non-Whites reported more supportive and obstructive behaviors than Whites, but race did not affect the relationships between family behaviors and self-care or HbA1C. Conclusion Involving family members in patients’ diabetes management may compromise patients’ self-care and glycemic control unless family members are taught to avoid obstructive behaviors. Practice Implications Our findings endorse interventions that help family members develop actionable plans to support patients’ self-care and train them to communicate productively about diabetes management. PMID:25282327

Post-growth annealing induced change of conductivity in As-doped ZnO grown by radio frequency magnetron sputtering

NASA Astrophysics Data System (ADS)

To, C. K.; Yang, B.; Su, S. C.; Ling, C. C.; Beling, C. D.; Fung, S.

2011-12-01

Arsenic-doped ZnO films were fabricated by radio frequency magnetron sputtering method at a relatively low substrate temperature of 200 °C. Post-growth annealing in air was carried out up to a temperature of 1000 °C. The samples were characterized by Hall measurement, positron annihilation spectroscopy (PAS), secondary ion mass spectroscopy (SIMS), and cathodoluminescence (CL). The as-grown sample was of n-type and it converted to p-type material after the 400 °C annealing. The resulting hole concentration was found to increase with annealing temperature and reached a maximum of 6 × 1017 cm-3 at the annealing temperature of 600 °C. The origin of the p-type conductivity was consistent with the AsZn(VZn)2 shallow acceptor model. Further increasing the annealing temperature would decrease the hole concentration of the samples finally converted the sample back to n-type. With evidence, it was suggested that the removal of the p-type conductivity was due to the dissociation of the AsZn(VZn)2 acceptor and the creation of the deep level defect giving rise to the green luminescence.

Ambipolar thermoelectric power of chemically-exfoliated RuO2 nanosheets

NASA Astrophysics Data System (ADS)

Kim, Jeongmin; Yoo, Somi; Moon, Hongjae; Kim, Se Yun; Ko, Dong-Su; Roh, Jong Wook; Lee, Wooyoung

2018-01-01

The electrical conductivity and Seebeck coefficient of RuO2 nanosheets are enhanced by metal nanoparticle doping using Ag-acetate solutions. In this study, RuO2 monolayer and bilayer nanosheets exfoliated from layered alkali metal ruthenates are transferred to Si substrates for device fabrication, and the temperature dependence of their conductivity and Seebeck coefficients is investigated. For pristine RuO2 nanosheets, the sign of the Seebeck coefficient changes with temperature from 350-450 K. This indicates that the dominant type of charge carrier is dependent on the temperature, and the RuO2 nanosheets show ambipolar carrier transport behavior. By contrast, the sign of the Seebeck coefficient for Ag nanoparticle-doped RuO2 nanosheets does not change with temperature, indicating that the extra charge carriers from metal nanoparticles promote n-type semiconductor behavior.

Effectiveness of training on preventative nutritional behaviors for type-2 diabetes among the female adolescents: Examination of theory of planned behavior.

PubMed

Maleki, Farzaneh; Hosseini Nodeh, Zahra; Rahnavard, Zahra; Arab, Masoume

2016-01-01

Since type-2 diabetes is the most common chronic disease among Iranian female adolescents, we applied theory of planned behavior to examine the effect of training to intention to preventative nutritional behaviors for type-2 diabetes among female adolescents. In this experimental study 200 (11-14 year old) girls from 8 schools of Tehran city (100 in each intervention and control group) were recruited based on cluster sampling method during two stages. For intervention group, an educational program was designed based on the theory of planned behavior and presented in 6 workshop sessions to prevent type-2 diabetes. The data were collected before and two months after the workshops using a valid and reliable (α=0.72 and r=0.80) authormade questionnaire based on Ajzens TPB questionnaire manual. The data were analyzed using t-test, chi-square test and analysis of covariance. Findings indicate that the two groups were homogeneous regarding the demographic characteristics before education, but the mean score of the theory components (attitudes, subjective norms, perceived behavioral control, and intention) was higher in the control group. Also, results showed all of the theory components significantly increased after the education in the intervention group (p=0.000). Training based on the theory of planned behavior enhances the intention to adherence preventative nutritional behaviors for type-2 diabetes among the studied female adolescents.

The Effects of Staff Training on the Types of Interactions Observed at Two Group Homes for Foster Care Children

ERIC Educational Resources Information Center

Crosland, Kimberly A.; Dunlap, Glen; Sager, Wayne; Neff, Bryon; Wilcox, Catherine; Blanco, Alfredo; Giddings, Tamela

2008-01-01

Objectives: An extensive literature base exists for behavioral parent training; however, few studies have focused on training direct care staff at group home and residential facilities for children. This study was conducted to determine whether a behavioral staff training program consisting of classroom training and in-home feedback would improve…

Differences in Students' Smoking-Related Knowledge, Attitudes, and Behaviors among Public, Factory, and Private Secondary Schools in Guangzhou, China

ERIC Educational Resources Information Center

Wen, Xiaozhong; Chen, Weiqing; Qian, Zhengmin; Muscat, Joshua E.; Lu, Ciyong; Ling, Wenhua

2008-01-01

Background: The prevalence of smoking among Chinese adolescents has dramatically increased in recent years. The purpose of this study was to examine the differences in smoking-related knowledge, attitudes, and behaviors among Chinese students in 3 types of secondary schools. Methods: This cross-sectional study was conducted among 3957 students of…

Types of motivating operations in interventions with problem behavior: a systematic review.

PubMed

Simó-Pinatella, David; Font-Roura, Josep; Planella-Morató, Joaquima; McGill, Peter; Alomar-Kurz, Elisabeth; Giné, Climent

2013-01-01

A motivating operation (MO) alters both the effectiveness of a stimulus as a reinforcer and the current frequency of all behavior that has been reinforced by that particular stimulus. This article reviews studies that have manipulated a MO during interventions with school-age participants with intellectual disabilities and problem behavior. A systematic review was conducted using the following major electronic databases: PsychInfo, Education Resources Information Center, Science Direct, Blackwell, SAGE, and Medline. A total of 31 published articles representing 55 participants was examined. Findings from this study suggest that the modification of a MO usually has an effect on the problem behavior by either establishing or abolishing its motivation. Furthermore, a relationship was found between the type of MO and the behavioral function identified. The theoretical and practical implications of these findings, limitations of this study and potential issues for future research are discussed.

High field conduction in Pb doped amorphous Se-Te system

NASA Astrophysics Data System (ADS)

Anjali, Patial, Balbir Singh; Thakur, Nagesh

2018-05-01

In the present study, DC conductivity measurements of as-Se80-xTe20Pbx (x = 0, 1 and 2) glassy alloys are made in the temperature range 298-318 K and in the voltage range 0-180 V. Current-voltage (I-V) characteristics point toward ohmic behavior at low electric field and non-ohmic is observed at high electric field. The variation of ln(I/V) against V are nearly found straight curves but slope of these curves does not decrease linearly with temperature indicates that the space charge limited conduction (SCLC) is absent. Instead the linear relation between ln(I) and V1/2 confirms that the conduction is either Poole-Frenkel type or Schottky emission. A detailed analysis shows that the dominant mechanism is Poole-Frenkel type conduction.

Transparent conductive p-type lithium-doped nickel oxide thin films deposited by pulsed plasma deposition

NASA Astrophysics Data System (ADS)

Huang, Yanwei; Zhang, Qun; Xi, Junhua; Ji, Zhenguo

2012-07-01

Transparent p-type Li0.25Ni0.75O conductive thin films were prepared on conventional glass substrates by pulsed plasma deposition. The effects of substrate temperature and oxygen pressure on structural, electrical and optical properties of the films were investigated. The electrical resistivity decreases initially and increases subsequently as the substrate temperature increases. As the oxygen pressure increases, the electrical resistivity decreases monotonically. The possible physical mechanism was discussed. And a hetero p-n junction of p-Li0.25Ni0.75O/n-SnO2:W was fabricated by depositing n-SnO2:W on top of the p-Li0.25Ni0.75O, which exhibits typical rectifying current-voltage characteristics.

Effect of small scattering centers on the thermoelectric properties of p-type SiGe alloys

NASA Technical Reports Server (NTRS)

Beaty, John S.; Rolfe, Jonathan L.; Vandersande, Jan W.

1991-01-01

Theory predicts that the addition of ultra-fine, inert, phonon-scattering centers to thermoelectric materials will reduce their thermal conductivity. To investigate this prediction, ultrafine particulates (20 to 120 A) of silicon nitride have been added to boron-doped, p-type, 80/20 SiGe. All of the SiGe samples produced from ultrafine powder have lower thermal conductivities than standard SiGe, but high-temperature heat treatment increases the thermal conductivity back to the value for standard SiGe. However, the SiGe samples with silicon nitride, inert, phonon-scattering centers retained the lower thermal conductivity after several heat treatments. A reduction of approximately 25 percent in thermal conductivity has been achieved in these samples. The magnitude of the reduction agrees with theoretical predictions.

Host-mediated effects of semipersistently transmitted Squash vein yellowing virus on sweetpotato whitefly (Hemiptera: Aleyrodidae) behavior and fitness

USDA-ARS?s Scientific Manuscript database

Alighting, settling and oviposition behavioral assays were conducted on Squash vein yellowing virus- (SqVYV-) infected and mock-inoculated squash and watermelon plants. Developmental time of immature stages, adult longevity, and fecundity were measured on SqVYV-infected and mock-inoculated squash p...

The Ecology and Acoustic Behavior of Minke Whales in the Hawaiian and Pacific Islands

DTIC Science & Technology

2011-09-30

with similar acoustic behaviors. RELATED PROJECTS Related projects are being conducted by Len Thomas, Vincent Janik, and Steve Martin. These...Cork, Ireland. 15-20 Aug. (Proceedings to be published by Springer). Marques, T.A., L. Thomas, S.W. Martin, D.K. Mellinger, S. Jarvis , R.P

Effectiveness of Hypnosis in Combination with Conventional Techniques of Behavior Management in Anxiety/Pain Reduction during Dental Anesthetic Infiltration.

PubMed

Ramírez-Carrasco, A; Butrón-Téllez Girón, C; Sanchez-Armass, O; Pierdant-Pérez, M

2017-01-01

Background and Objective . Anxiety/pain are experiences that make dental treatment difficult for children, especially during the time of anesthesia. Hypnosis is used in pediatric clinical situations to modify thinking, behavior, and perception as well as, recently, in dentistry; therefore the aim of this study was to evaluate the effectiveness of hypnosis combined with conventional behavior management techniques during infiltration anesthetic. Methods . Anxiety/pain were assessed with the FLACC scale during the anesthetic moment, as well as heart rate variability and skin conductance before and during the anesthetic moment, between the control and experimental group. Results . A marginal statistical difference ( p = 0.05) was found in the heart rate between baseline and anesthetic moment, being lower in the hypnosis group. No statistically significant differences were found with the FLACC scale or in the skin conductance ( p > 0.05). Conclusion . Hypnosis combined with conventional behavior management techniques decreases heart rate during anesthetic infiltration showing that there may be an improvement in anxiety/pain control through hypnotic therapy.

Effectiveness of Hypnosis in Combination with Conventional Techniques of Behavior Management in Anxiety/Pain Reduction during Dental Anesthetic Infiltration

PubMed Central

Ramírez-Carrasco, A.; Butrón-Téllez Girón, C.; Sanchez-Armass, O.

2017-01-01

Background and Objective. Anxiety/pain are experiences that make dental treatment difficult for children, especially during the time of anesthesia. Hypnosis is used in pediatric clinical situations to modify thinking, behavior, and perception as well as, recently, in dentistry; therefore the aim of this study was to evaluate the effectiveness of hypnosis combined with conventional behavior management techniques during infiltration anesthetic. Methods. Anxiety/pain were assessed with the FLACC scale during the anesthetic moment, as well as heart rate variability and skin conductance before and during the anesthetic moment, between the control and experimental group. Results. A marginal statistical difference (p = 0.05) was found in the heart rate between baseline and anesthetic moment, being lower in the hypnosis group. No statistically significant differences were found with the FLACC scale or in the skin conductance (p > 0.05). Conclusion. Hypnosis combined with conventional behavior management techniques decreases heart rate during anesthetic infiltration showing that there may be an improvement in anxiety/pain control through hypnotic therapy. PMID:28490941

Family behaviors and type 2 diabetes: What to target and how to address in interventions for adults with low socioeconomic status.

PubMed

Mayberry, Lindsay Satterwhite; Harper, Kryseana J; Osborn, Chandra Y

2016-09-01

Diabetes-specific family behaviors are associated with self-care and glycemic control among adults with type 2 diabetes. Formative research is needed to inform assessment of these behaviors and interventions to address obstructive family behaviors (sabotaging and nagging/arguing), particularly among racial/ethnic minorities and low-income adults who struggle most with self-care adherence. We conducted a mixed-methods study with adults with type 2 diabetes at a Federally Qualified Health Center to better understand experiences with diabetes-specific family behaviors and willingness to engage family members in diabetes interventions. Participants completed a phone survey (N = 53) and/or attended a focus group (n = 15). Participants were 70% African American and had low socioeconomic status (96% annual income

NiO Nanofibers as a Candidate for a Nanophotocathode

PubMed Central

Macdonald, Thomas J.; Xu, Jie; Elmas, Sait; Mange, Yatin J.; Skinner, William M.; Xu, Haolan; Nann, Thomas

2014-01-01

p-type NiO nanofibers have been synthesized from a simple electrospinning and sintering procedure. For the first time, p-type nanofibers have been electrospun onto a conductive fluorine doped tin oxide (FTO) surface. The properties of the NiO nanofibers have been directly compared to that of bulk NiO nanopowder. We have observed a p-type photocurrent for a NiO photocathode fabricated on an FTO substrate. PMID:28344222

Synthesis, characterization and air stable semiconductor properties of thiophene-condensed pyrene derivatives

NASA Astrophysics Data System (ADS)

Moriguchi, Tetsuji; Higashi, Makoto; Yakeya, Daisuke; Jalli, Venkataprasad; Tsuge, Akihiko; Okauchi, Tatsuo; Nagamatsu, Shuichi; Takashima, Wataru

2017-01-01

New and simple polyaromatic compounds containing two thiophene rings were prepared via photo-cyclization and their structural and photophysical properties were evaluated via 1H NMR spectroscopy and X-ray crystallographic analysis. On the basis of X-ray analysis, it was determined that the molecular structure of the compound was highly strained and that they contain two hetero [4] helicene moieties. The compounds were investigated as active layer in p-type organic field-effect transistors (p-OFET) in top contact type devices. Notably, the compound containing two thiophene components exhibited very stable p-type semiconducting behavior in moist air.

Cognitive Training Sustainably Improves Executive Functioning in Middle-Aged Industry Workers Assessed by Task Switching: A Randomized Controlled ERP Study

PubMed Central

Gajewski, Patrick D.; Freude, Gabriele; Falkenstein, Michael

2017-01-01

Recently, we reported results of a cross-sectional study investigating executive functions in dependence of aging and type of work. That study showed deficits in performance and electrophysiological activity in middle-aged workers with long-term repetitive and unchallenging work. Based on these findings, we conducted a longitudinal study that aimed at ameliorating these cognitive deficits by means of a trainer-guided cognitive training (CT) in 57 further middle-aged workers with repetitive type of work from the same factory. This study was designed as a randomized controlled trail with pre- (t1), post- (t2), and a 3-month follow-up (t3) measure. The waiting control group was trained between t2 and t3. The training lasted 3 months (20 sessions) and was evaluated with the same task switching paradigm used in the previous cross-sectional study. The CT improved performance in accuracy at the behavioral level and affected the electrophysiological correlates of retrieval of stimulus-response sets (P2), response selection (N2), and error detection (Ne), thus unveiling the neuronal background of the behavioral effects. The same training effects were observed in the waiting control group after CT at t3. Moreover, at t3, most of the behavioral and electrophysiological training-induced changes were found stable. Hence, CT appears to be an important intervention for compensating cognitive deficits in executive functions in middle-aged employees with cognitively unchallenging work. PMID:28275347

On the Time Course of Accessing Meaning in a Second Language: An Electrophysiological and Behavioral Investigation of Translation Recognition

PubMed Central

Guo, Taomei; Misra, Maya; Tam, Joyce W.; Kroll, Judith F.

2012-01-01

In 2 experiments, relatively proficient Chinese–English bilinguals decided whether Chinese words were the correct translations of English words. Critical trials were those on which incorrect translations were related in lexical form or meaning to the correct translation. In Experiment 1, behavioral interference was revealed for both distractor types, but event-related potentials (ERPs) revealed a different time course for the 2 conditions. Semantic distractors elicited effects primarily on the N400 and late positive component (LPC), with a smaller N400 and a smaller LPC over the posterior scalp but a larger LPC over the anterior scalp relative to unrelated controls. In contrast, translation form distractors elicited a larger P200 and a larger LPC than did unrelated controls. To determine whether the translation form effects were enabled by the relatively long, 750-ms stimulus onset asynchrony (SOA) between words, a 2nd ERP experiment was conducted using a shorter, 300-ms, SOA. The behavioral results revealed interference for both types of distractors, but the ERPs again revealed different loci for the 2 effects. Taken together, the data suggest that proficient bilinguals activate 1st-language translations of words in the 2nd language after they have accessed the meaning of those words. The implications of this pattern for claims about the nature of cross-language activation when bilinguals read in 1 or both languages are discussed. PMID:22686844

Patterns of Adolescent Bullying Behaviors: Physical, Verbal, Exclusion, Rumor, and Cyber

PubMed Central

Wang, Jing; Iannotti, Ronald J.; Luk, Jeremy W.

2012-01-01

Patterns of engagement in cyber bullying and four types of traditional bullying were examined using latent class analysis (LCA). Demographic differences and externalizing problems were evaluated across latent class membership. Data were obtained from the 2005–2006 Health Behavior in School-aged Survey and the analytic sample included 7,508 U.S. adolescents in grades 6 through 10. LCA models were tested on physical bullying, verbal bullying, social exclusion, spreading rumors, and cyber bullying behaviors. Three latent classes were identified for each gender: All-Types Bullies (10.5% for boys and 4.0% for girls), Verbal/Social Bullies (29.3% for boys and 29.4% for girls), and a Non-Involved class (60.2% for boys and 66.6% for girls). Boys were more likely to be All-Types Bullies than girls. The prevalence rates of All-Types and Verbal/Social Bullies peaked during grades 6 to 8 and grades 7 & 8, respectively. Pairwise comparisons across the three latent classes on externalizing problems were conducted. Overall, the All-Types Bullies were at highest risk of using substances and carrying weapons, the Non-Involved were at lowest risk, and the Verbal/Social Bullies were in the middle. Results also suggest that most cyber bullies belong to a group of highly aggressive adolescents who conduct all types of bullying. This finding does not only improve our understanding of the relation between cyber bullying and traditional bullying, but it also suggests that prevention and intervention efforts could target cyber bullies as a high-risk group for elevated externalizing problems. PMID:22710019

Effects on enantiomeric drug disposition and open-field behavior after chronic treatment with venlafaxine in the P-glycoprotein knockout mice model.

PubMed

Karlsson, Louise; Hiemke, Christoph; Carlsson, Björn; Josefsson, Martin; Ahlner, Johan; Bengtsson, Finn; Schmitt, Ulrich; Kugelberg, Fredrik C

2011-05-01

P-glycoprotein (P-gp) plays an important role in the efflux of drugs from the brain back into the bloodstream and can influence the pharmacokinetics and pharmacodynamics of drug molecules. To our knowledge, no studies have reported pharmacodynamic effects of any antidepressant drug in the P-gp knockout mice model. The aim of this study was to investigate the enantiomeric venlafaxine and metabolite concentrations in serum and brain of abcb1ab⁻/⁻ mice compared to wild-type mice upon chronic dosing, and to assess the effect of venlafaxine treatment on open-field behavior. P-gp knockout and wild-type mice received two daily intraperitoneal injections of venlafaxine (10 mg/kg) over ten consecutive days. Locomotor and rearing activities were assessed on days 7 and 9. After 10 days, drug and metabolite concentrations in brain and serum were determined using an enantioselective LC/MS/MS method. The brain concentrations of venlafaxine and its three demethylated metabolites were two to four times higher in abcb1ab⁻/⁻ mice compared to abcb1ab+/+ mice. The behavioral results indicated an impact on exploration-related behaviors in the open-field as center activity was increased, and rears were decreased by venlafaxine treatment. Our results show that P-gp at the blood-brain barrier plays an important role in limiting brain entry of the enantiomers of venlafaxine and its metabolites after chronic dosing. Taken together, the present pharmacokinetic and pharmacodynamic findings offer the possibility that the expression of P-gp in patients may be a contributing factor for limited treatment response.

Electronic structure of p-type transparent conducting oxide CuAlO2

NASA Astrophysics Data System (ADS)

Mo, Sung-Kwan; Yoon, Joonseok; Liu, Xiaosong; Yang, Wanli; Mun, Bongjin; Ju, Honglyoul

2014-03-01

CuAlO2 is a prototypical p-type transparent conducting oxide. Despite its importance for potential applications and number of studies on its band structure and gap characteristics, experimental study on the momentum-resolved electronic structure has been lacking. We present angle-resolved photoemission data on single crystalline CuAlO2 using synchrotron light source to reveal complete band structure. Complemented by the x-ray absorption and emission spectra, we also study band gap characteristics and compare them with theory.

Electrical transport through Pb(Zr,Ti)O3 p-n and p-p heterostructures modulated by bound charges at a ferroelectric surface: Ferroelectric p-n diode

NASA Astrophysics Data System (ADS)

Watanabe, Yukio

1999-05-01

Current through (Pb,La)(Zr,Ti)O3 ferroelectrics on perovskite semiconductors is found to exhibit diode characteristics of which polarity is universally determined by the carrier conduction-type semiconductors. A persisting highly reproducible resistance modulation by a dc voltage, which has a short retention, is observed and is ascribed to a band bending of the ferroelectric by the formation of charged traps. This interpretation is consistent with a large relaxation current observed at a low voltage. On the other hand, a reproducible resistance modulation by a pulse voltage, which has a long retention, is observed in metal/(Pb,La)(Zr,Ti)O3/SrTiO3:Nb but not in metal/(Pb,La)(Zr,Ti)O3/(La,Sr)2CuO4 and is attributed to a possible band bending due to the spontaneous polarization (P) switching. The observed current voltage (IV) characteristics, the polarity dependence, the relaxation, and the modulation are explicable, if we assume a p-n or a p-p junction at the ferroelectric semiconductor interface (p: hole conduction type, n: electron conduction type). The analysis suggests that an intrinsically inhomogeneous P (∇P) near the ferroelectric/metal interface is likely very weak or existing in a very thin layer, when a reaction of the metal with the ferroelectric is eliminated. Additionally, the various aspects of transport through ferroelectrics are explained as a transport in the carrier depleted region.

Increased Body Mass Index Associated with Increased Risky Sexual Behaviors

PubMed Central

Gordon, Lonna P.; Diaz, Angela; Soghomonian, Christine; Nucci-Sack, Anne T.; Weiss, Jocelyn M.; Strickler, Howard D.; Burk, Robert D.; Schlecht, Nicolas F.; Ochner, Christopher N.

2015-01-01

Study Objective The increasing prevalence of adolescent obesity has led to consideration of the potential effect of obesity on risky sexual behaviors. The current study examined whether body mass index (BMI) was related to age at sexual debut, type of sexual behavior, partner number, and condom use in a population of adolescent women at high risk for obesity and risky sexual behaviors. Study Design Cross-sectional examination of 860 sexually active, predominantly minority, adolescent women who received medical care at an urban health center from 2007 – 2013. Intervention Self-reported age at sexual debut, types of sexual intercourse, number of partners and condom use was compared to clinically – assessed BMI. Results Body mass index was positively associated with number of sexual partners (p = 0.001) and history of attempted anal intercourse (p = 0.002). An inverse association was observed with age at first anal intercourse (p = 0.040). Conclusions In this sample of adolescent women, increased BMI was associated with riskier sexual practices at a younger age. This study suggests that overweight and obese adolescents are a vulnerable population who may need targeted sexual health counseling. PMID:26358938

Electrical properties of n-type GaSb substrates and p-type GaSb buffer layers for InAs/InGaSb superlattice infrared detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchel, W. C., E-mail: William.Mitchel.1@us.af.mil; Haugan, H. J.; Mou, Shin

2015-09-15

Lightly doped n-type GaSb substrates with p-type GaSb buffer layers are the preferred templates for growth of InAs/InGaSb superlattices used in infrared detector applications because of relatively high infrared transmission and a close lattice match to the superlattices. We report here temperature dependent resistivity and Hall effect measurements of bare substrates and substrate-p-type buffer layer structures grown by molecular beam epitaxy. Multicarrier analysis of the resistivity and Hall coefficient data demonstrate that high temperature transport in the substrates is due to conduction in both the high mobility zone center Γ band and the low mobility off-center L band. High overallmore » mobility values indicate the absence of close compensation and that improved infrared and transport properties were achieved by a reduction in intrinsic acceptor concentration. Standard transport measurements of the undoped buffer layers show p-type conduction up to 300 K indicating electrical isolation of the buffer layer from the lightly n-type GaSb substrate. However, the highest temperature data indicate the early stages of the expected p to n type conversion which leads to apparent anomalously high carrier concentrations and lower than expected mobilities. Data at 77 K indicate very high quality buffer layers.« less

Mechanisms of elevated-temperature deformation in the B2 aluminides NiAl and CoAl

NASA Technical Reports Server (NTRS)

Yaney, D. L.; Nix, W. D.

1988-01-01

A strain rate change technique, developed previously for distinguishing between pure-metal and alloy-type creep behavior, was used to study the elevated-temperature deformation behavior of the intermetallic compounds NiAl and CoAl. Tests on NiAl were conducted at temperatures between 1100 and 1300 K while tests on CoAl were performed at temperatures ranging from 1200 to 1400 K. NiAl exhibits pure-metal type behavior over the entire temperature range studied. CoAl, however, undergoes a transition from pure-metal to alloy-type deformation behavior as the temperature is decreased from 1400 to 1200 K. Slip appears to be inherently more difficult in CoAl than in NiAl, with lattice friction effects limiting the mobility of dislocations at a much higher tmeperature in CoAl than in NiAl. The superior strength of CoAl at elevated temperatures may, therefore, be related to a greater lattice friction strengthening effect in CoAl than in NiAl.

Composite Behavior of Insulated Concrete Sandwich Wall Panels Subjected to Wind Pressure and Suction.

PubMed

Choi, Insub; Kim, JunHee; Kim, Ho-Ryong

2015-03-19

A full-scale experimental test was conducted to analyze the composite behavior of insulated concrete sandwich wall panels (ICSWPs) subjected to wind pressure and suction. The experimental program was composed of three groups of ICSWP specimens, each with a different type of insulation and number of glass-fiber-reinforced polymer (GFRP) shear grids. The degree of composite action of each specimen was analyzed according to the load direction, type of the insulation, and number of GFRP shear grids by comparing the theoretical and experimental values. The failure modes of the ICSWPs were compared to investigate the effect of bonds according to the load direction and type of insulation. Bonds based on insulation absorptiveness were effective to result in the composite behavior of ICSWP under positive loading tests only, while bonds based on insulation surface roughness were effective under both positive and negative loading tests. Therefore, the composite behavior based on surface roughness can be applied to the calculation of the design strength of ICSWPs with continuous GFRP shear connectors.

The role of oxidation in the fretting wear process

NASA Technical Reports Server (NTRS)

Bill, R. C.

1980-01-01

Fretting experiments were conducted on titanium, a series of Ni-Cr-Al alloys and on some high temperature turbine alloys at room temperature and at elevated temperatures in air and in various inert environments. It was found that, depending on temperature and environment, the fretting behavior of the materials examined could be classified according to four general types of behavior. Briefly, these types of behavior were: (1) the complete absence of oxidation, as in inert environments, generally leading to low rates of fretting wear but high fretting friction; (2) gradual attrition of surface oxide with each fretting stroke, found in these experiments to operate in concert with other dominating mechanisms; (3) rapid oxidation at surface fatigue damage sites, resulting in undermining and rapid disintegration of the load bearing surface; and (4) the formation of coherent, protective oxide film, resulting in low rates of fretting wear. An analytical model predicting conditions favorable to the fourth type of behavior was outlined.

AN ACCURATE AND EFFICIENT ALGORITHM FOR NUMERICAL SIMULATION OF CONDUCTION-TYPE PROBLEMS. (R824801)

EPA Science Inventory

Abstract

A modification of the finite analytic numerical method for conduction-type (diffusion) problems is presented. The finite analytic discretization scheme is derived by means of the Fourier series expansion for the most general case of nonuniform grid and variabl...