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Purpose This study examines the associations between migraine headaches, well-being, and health care use among a sample of underserved older African American adults. Controlling for relevant variables, the association between migraine headaches and (1) health care utilization, (2) health-related quality of life (HRQoL), and (3) physical and mental health outcomes was examined. Methods Our sample included 760 older African American adults from South Los Angeles recruited through convenience and snowball sampling. In addition to demographic variables, our survey included validated instruments, such as the SF-12 QoL, Short-Form McGill Pain Questionnaire, and the Geriatric Depression Scale. Data analysis included 12 independent multivariate models using multiple linear regression, log transferred linear regression, binary and multinomial logistic regression, and generalized linear regression with Poisson distribution. Results Having migraine was associated with three categories of outcomes: (1) higher level of health care utilization measured by (i) emergency department admissions and (ii) number of medication use; (2) lower level of HRQoL and health status measured by (i) lower self-rated health (ii) physical QoL, and (iii) mental QoL; and (3) worse physical and mental health outcomes measured by (i) higher number of depressive symptoms, (ii) higher level of pain, (iii) sleep disorder, and (iv) being disabled. Conclusions Migraine headache significantly was associated with quality of life, health care utilization, and many health outcomes of underserved African American middle-aged and older adults. Diagnoses and treatments of migraine among underserved older African American adults require multi-faceted and culturally sensitive interventional studies.

Electrochemical nonenzymatic biosensors with no immobilization and degradation problem, have recently attracted growing attention due to stability and reproducibility. Here, a comparative study was conducted to precisely evaluate the nonenzymatic glucose sensing of pure/oxidized Ni, Co, and their bimetal nanostructures grown on electrospun carbon nanofibers (ECNFs). This method provides a low-cost free stand electrode. The prepared nanostructures with superb physiochemical features exhibited sensitivity (from 66.28 to 610.6 μA mM−1 cm−2), linear range of 2-10 mM, limit of detection in the range of 1 mM, and response time (

Any improvement in drilling technology is critical for developing the oil and gas industry. The success of drilling operations largely depends on drilling fluid characteristics. Drilling fluids require enough viscosity to suspend the particles and transport them to the surface and enough capability to control the fluid loss into the formation. Rheology and filtration characteristics of drilling fluids are crucial factors to consider while ensuring the effectiveness of a drilling operation. Graphene oxide (GO), xanthan gum (XG), and low-viscosity carboxymethyl cellulose (CMC LV) are being utilized in this research to produce high-performance, low-solid water-based drilling fluids (WDFs). Rheological and filtration behaviors of GO/XG/CMC LV-WDF were investigated as a function of GO, XG, and CMC LV at low concentrations (0.0-0.3% w/w) and atmospheric conditions. According to the findings, GO improved the rheological and filtration capabilities of the WDF. By adding 0.15 wt % GO, shear stress could be doubled, especially at a high shear rate of 1022 s-1. The plastic viscosity of the fluid could be expanded from 6 to 13 centipoise, and a fluid loss of 8.7 mL over 30 min was observed during the API fluid test, which would be lower than the suggested fluid loss value (15.0 mL) for water-based mud. At the same concentration of XG and CMC LV, XG had a more significant influence on rheological characteristics in the presence of GO. Adding 0.3 wt % XG could increase fluid shear stress from 20.21 to 30.21 Pa at a high shear rate of 1022 s-1. In contrast, CMC LV had more impact on filtration properties, acting as a filtration control agent by decreasing the API fluid loss of fluid from 21.4 to 14.2 mL over 30 min. The addition of XG and CMC LV to the GO solution may influence the microstructure of the filter cake, resulting in a tree-root morphology. Indeed, in the GO/CMC LV solution, the individual platelets may bind together, form a jellyfish shape, and block the micropores. The incorporation of CMC LV helped develop compact filter cakes, resulting in excellent filtration. Five rheological models were employed to match the fluid parameters quantitatively. The Herschel-Bulkley model outperformed the other models in simulating fluid rheological behavior. The findings of this study can be utilize to provide low-cost, stable, and environmentally compatible additives for drilling low-pressure, depleted, and fractured oil and gas reservoirs.

Urogynakologie und plastische Beckenbodenchirurgie beschaftigen sich mit der Diagnostik und konservativen sowie operativen Therapie von Erkrankungen des weiblichen Beckenbodens. Dabei spielt insbesondere die gestorte Sexualfunktion infolge von anatomischen Verletzungen nach vaginalen Entbindungen eine zentrale Rolle. Die chirurgische Rekonstruktion der Scheide, der Faszien und Sehnen sowie von Harnrohre, Vulva und Anus nach traumatischen Entbindungen ist eine Voraussetzung fur die Funktionalitat, und somit ist die Behandlung des Beckenbodens immer auch eine Sexualtherapie. Korperliche Defizite fuhren zu somatischen und psychosomatischen Storungen, die einem lustvollen Erleben des Sexuallebens entgegenstehen. Somatisch konnen Inkontinenz, Senkung- und Fremdkorpergefuhl, Weitegefuhl, Kontaktverlust zum Penis, Empfindungs- und Orgasmusverlust, Ein- und Austritt von Wasser oder Luft in und aus der Scheide, Harn- und Stuhlinkontinenz sowie Stuhlentleerungsstorungen bestehen. Hierdurch konnen Unsicherheit und das Gefuhl von Unattraktivitat erzeugt und die Libido reduziert werden, was tiefe Auswirkungen auf die Psyche der betroffenen Frau, aber auch auf deren soziales Umfeld und deren Paarbeziehung hat. Die haufig gewunschte sexuelle Aktivitat im Senium kann durch gesundheitliche Beeintrachtigungen im Allgemeinen und Beckenbodenstorungen im Besonderen gestort sein. Arztinnen und Arzte mussen die Tabuisierung der Sexualitat im Alter und von Sexualstorungen generell durch aktives Nachfragen durchbrechen. Sowohl konservative als auch operative Therapieansatze konnen hier Abhilfe schaffen, wobei insbesondere die breitflachige Netzchirurgie hohe Risiken fur die Dyspareunie birgt.

Aims: According to the nature of multiple sclerosis (MS) disease, the patients with MS are always facing with problems in their interpersonal communications. Therefore, the study investigates the effectiveness of group-based solution-focused therapy on interpersonal problems in patients with multiple sclerosis Materials and methods: The research method was semi-experimental with pretest/posttest and control group design. A number of 40 members of Multiple Sclerosis Association of Mashhad were selected through convenience sampling and assigned to experimental and control groups randomly. The experimental group has been received group-based solution-focused intervention and the control group was in wait list. To gather the data Barkham, Hardy, and Startup’s Inventory of Interpersonal Problems (IIP-32) was used. The obtained data analyzed by MANCOVA test through SPSS-23 software. Findings: According to the mean of the interpersonal problems of the experimental group rather than the mean of the interpersonal problems of control group, it can be concluded that the group-based solution-focused therapy lead to reduce the interpersonal problems of experimental group (P>.001, F= 81.31). The effect size was .69. Conclusion: According to group-based solution-focused therapy has a non-pathological view as communicative approach, could be effective on resolving the interpersonal problems of patients with MS.

Conductive inks are considered very promising for device fabrication on flexible substrates and large areas. Silver (Ag)-graphene hybrid inks offer many opportunities, including cost/conductivity optimization for different applications. In this work, several conductive hybrid ink formulations containing Ag nanostructures and graphene derivatives were prepared using different processing strategies and thoroughly characterized. SEM and morphological studies were used to explore the probable reasons for the difference in electrical conductivity of various inks. Strong interaction between Ag nanoparticles and graphene layers prevented the formation of island structures in films, especially at high temperatures. While Ag nanowires and graphene layers formed a uniform, dense three-dimensional network, offering high electrical conductivity. Additionally, an improvement of electrical conductivity by using graphene quantum dots as a graphene component in hybrid inks was observed, which was related to creating new conductive bridges. The highest conductivity of prepared inks varied in the range of 2.67 × 102 S/cm to 4.0 × 104 S/cm. Finally, formulation guidelines were offered to be used for inks by several printing methods.

In this work behavior of polyaniline/molybdenum disulfide-manganese dioxide (PANI/MoS2−MnO2) composite on Glassy Carbon electrode (GCE) for supercapacitor applications was studied. For this purpose, the bulk MoS2 was exfoliated into few layer nanosheets with specific solvent then MoS2−MnO2 composite was synthesized using hydrothermal technique and hybrid PANI/MoS2−MnO2 electrode was fabricated employing electropolymerization technique. The ternary composite serves as an electrode for supercapacitor in both three and two-electrode systems which has more superior electrochemical properties compared to the binary complex. The supercapacitor electrode consists of MoS2 nanosheets as sub-layer support, MnO2 providing electrochemical performance and polyaniline improving high electric conductivity. The supercapacitor performances of the composite were analyzed by Cyclic Voltammetry (CV), Chronopotentiometry (CP) and Electrochemical Impedance Spectroscopy (EIS) analyses. The maximum specific capacitance of PANI, MoS2−MnO2 and PANI/MoS2−MnO2 nanocomposite electrodes was calculated 333, 358 and 479 Fg−1 at the scan rate of 5 mVs−1, respectively. Likewise, the applicable two-electrode device using electrode configurations composed of PANI-MoS2−MnO2//PANI-MoS2−MnO2 showed specific capacitance of 259 Fg−1 at current density of 1 Ag−1. Also, the electrode possessed specific energy of 35.97 Wh kg−1 at a specific power of 500 W kg−1 and excellent cycling stability of 94.1% after 4000 cycles at 16 Ag−1.

A transparent planar electrode from thermally reduced graphene oxide (TRGO) incorporated with a photoconductive thin film of zinc oxide (ZnO) was successfully employed in a visible-blind ultraviolet (UV) photodetector. The TRGO layer was obtained from thermal reduction of drop-cast GO layer at the temperature of 400 °C after which the electrical resistance of layer decreased four orders of magnitude to ~100 Ω. Then a pure and uniform ZnO thin film with the thickness of ~80 nm was sputtered on the TRGO layer. High UV absorption and visible transparency with the average transmittance of 92% in the range of 400–800 nm (T400−800) were obtained for the ZnO thin film. Moreover, the TRGO layer was highly capable in collecting photogenerated electrons from ZnO thin film and efficient transport of charge carriers to the contact electrodes. The ZnO/TRGO device showed an ideal Ohmic behavior and high visible-light transparency with T400−800 = 80%. Furthermore, the results of current–time measurements with cyclic exposure of the device to UV light indicated stable ON/OFF switching states and highly repeatable photoresponse.

Background: While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria. Methods: In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced. Results: GBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes. Conclusions: GBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC B Y. Published by BMJ.

Green and efficient mass production of graphene sheets with high quality and electrical conductivity is intriguing for both academic scientists and industry. Among numerous production methods suffering from complexity or harsh chemical media, direct and high-yield exfoliation of graphite in water seems to be the best choice. In this study, efforts were made to prepare high-quality and stable graphene dispersions with the highest possible concentrations through an ultrasound-assisted liquid-phase exfoliation (LPE) in water directly from two types of natural graphites. The rigorous structural, morphological and electrical analyses were conducted on both graphite and graphene samples to quantitatively identify the effect of graphite sources on the LPE yield and the quality of the graphene nanosheets produced in the presence of an ionic surfactant. The results obtained by TEM, AFM, XRD and Raman spectroscopy indicated the successful and efficient production of single and few layer graphene sheets with the remarkable concentration of 3.18[Formula: see text]mg.ml[Formula: see text] in water. Moreover, the results signified that the structural quality, electrical conductivity and production yield of the graphene layers undoubtedly depend on the structural properties of graphite source. In fact, the graphite source greatly influences the final properties and potential applications of the produced graphene layer and the results are so important for the future graphene industry.

Manufacturing proper electrodes for supercapacitors including high capacitance is of great importance for current increased demand for energy storage devices. In this paper, we evaluated metal nanoparticles infused in electrospun carbon nanofibers (ECNF) synthesized by electrospinning, followed by thermal treatment for supercapacitors’ electrode applications. The electrodes were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and cyclic voltammetry. The characterization results indicated that the metal/ECNF samples have fibrous morphology, porous structure with a high specific surface area, including dispersed metal nanoparticles. The effect of embedding various transition metals, such as Co, Ni, and Cu on the electrochemical performance of ECNF has been investigated. The incorporation of Cu into ECNF resulted in the highest specific capacitance. At the scan rate of 5 mV s−1, the specific capacitance of the Cu/ECNF sample was 332 F g−1 while it was 4 F g−1 for the ECNF sample.

In this work, a facile and scalable method to produce cellulose based flexible electrodes is introduced. Composite paper electrodes from recycled paper pulp and graphene oxide (GO) were fabricated by solvent casting at room temperature. Electrical conductivity and surface chemistry of the nanocomposite samples were tuned by chemical reduction of GO. Contact angle measurements showed a change in water droplet angle from 0° to 89° depending on the GO content and degree of reduction. Electrical measurements depicted high electrical conductivity with an ideal Ohmic behavior for the composite paper electrodes. Sheet resistance of the sample containing 4 wt% of reduced GO (rGO) was 1.649 × 103 Ω/□ which is 5 orders of magnitude higher than paper pulp. The obtained sheet resistance for the sample with 16 wt% rGO was remarkably high for cellulose based conductive electrode compared with previously reported data. Moreover, the sample containing only 0.5 wt% of rGO showed 40% higher modulus than the neat recycled paper in tension. The resultant nanocomposite can be introduced as a highly conductive and low cost flexible electrode.

High quality indium tin oxide/polyethylene terephthalate (ITO/PET) electrode with sheet resistance as low as 1.16 Ω/□ and the optical transmittance of 91 % at the wavelength of 600 nm was fabricated. The room-temperature radio frequency (RF) magnetron sputtering technique was used to deposit ITO thin film on PET substrate under low RF power without oxygen flow or post treatment. The remarkable value of 118.5 × 10−3 Ω−1 was achieved for the figure of merit in the 93 nm thick ITO thin film, due to the fine tuning of the sputtering parameters. An entirely Ohmic behavior was recorded for the ITO/PET electrode on the copper contacts suggesting that the product is highly capable for application in optoelectronic devices. The results of field emission scanning electron microscopy and atomic force microscopy demonstrated film consistency with a desired surface morphology giving a Rrms value of 2.073 nm. The elemental, chemical and phase analyses further revealed that the deposited ITO thin film on the PET substrate was pure and amorphous.

Graphene, an outstanding material with remarkable electrical, mechanical and thermal properties, has found tremendous potential in electronic devices. Here we report the direct and irreversible reduction of graphene oxide (GO) ultrathin film (UTF) by application of 30 V bias on GO device under the ambient condition. During the process, an ultrahigh current density flowed through UTF resulting in the Joule-heat generation. The heat effectively removed the oxygen-containing groups from GO and restored graphene layer π-conjugated system reducing the electrical resistance down to ~10.7 Ω. The film also exhibited a linear, symmetric and hysteresis-free current response to the biases in the range of −2 to 2 V. Moreover, the sheet resistance as low as ~125 Ω/□ and optical transmittance of 91 % at 550 nm demonstrated that the reduced GO (rGO) UTF is superior to the conventional transparent electrodes. The rGO transparent conductive film sustained an ultrahigh current density in the order of 107 A cm−2 and showed high current stability in the saturated state, which make it an ideal candidate for transparent electrode applications.

A novel, simple and effective surface passivation technique is introduced to enhance UV spectrum selectivity of ZnO nanoparticles (NPs). The technique which exploits an absorbed layer of dimethylformamide, enables the synthesis and surface passivation of ZnO NPs through a single-step process. Pure ZnO NPs and passivated ones were characterized to evaluate the integrity of passivating layer as well as quality of the final product. Morphological examinations were performed using field-emission scanning and transmission electron microscopies. X-ray diffractometry, energy dispersive X-ray and fourier-transform infrared spectroscopies were employed to analyze the phase and chemical composition of the samples. We also compared optical properties of the surface-passivated and pure ZnO NPs. Photoluminescence measurements revealed a peak value for UV emission at 394 nm and one for violet emission at 412 nm for the passivated and pure samples; respectively. A significant enhancement was observed in the spectrum selectivity and absorption efficiency of the passivated ZnO NPs in the UV range. The passivated NPs exhibited high UV-to-visible rejection ratio and UV-blocking capacity which provide a promising candidate for visible-blind UV photodetectors and UV shielding applications.

In this study, a highly sensitive and high-gain metal-semiconductor-metal photodetector was successfully fabricated based on textured silicon substrates. Texturing of silicon substrate is an efficient technique to control its surface reflectivity by increasing the specific surface area. A combination of porous and pyramidal structures of silicon was introduced to dramatically enhance the light-capturing ability and minimize the reflection coefficient of the silicon substrates. To fabricate pyramidal structures, selective chemical dissolution of silicon was carried out. To form porous structures on pyramidal silicon, electrochemical etching process with different etching time was followed. The morphology and structure of samples were characterized using field-emission scanning electron microscopy (FESEM) and X-ray diffractometry (XRD). The optical properties were investigated using Raman, photoluminescence (PL) and reflectance spectroscopy. Results indicated that the optical reflectivity can be minimized when an optimal etching time is applied which can be due to the enhancement in the exposed area and ability of light capturing. The enhanced porosity of the optimized substrate was illustrated by its elevated PL intensity. For studying the effect of porous layer on the optoelectrical properties of pyramidal structures, metal-semiconductor-metal (MSM) photodetectors were fabricated by deposition of Schottky contacts of Au on different samples. The device with the optimal porous layer exhibited enhanced sensitivity to the incident illumination due to the huge surface area and reduction in the reflection coefficient. Moreover, the ultrafast sensing behavior of this device reflects its improved optoelectrical performance in light detection.

Drilling in geothermal wells is always the most expensive part of operation. Also, we know when go deep in layers, we always can absorb more heat and energy. This case can make some part of operation more expensive to go from shallow geothermal reservoirs to deep geothermal reservoirs. Managed pressure drilling (MPD) is an effective solution to obviate the drilling problems of narrow drilling window between the pore and fracture pressure, such as well kick and loss and well collapse and stuck. The Constant Bottom Hole Pressure (CBHP) technique, one of the MPD variants, was selected to freeze bottom hole pressure in narrow area between pore and fracture pressure as a safe method to drill without loss and gain. In this paper tried to control the ECD in upper sections to be able to drill in narrow drilling margin. Drilling window between collapse and fracture pressure is normally closed due to geological reasons, which in turn leads to creation of a boundary at which the dynamic formation losses could not be properly controlled.

Der Wunsch nach Sexualitat spielt auch im Senium eine erhebliche Rolle. Beeintrachtigt sein kann sie durch eine gestorte oder nicht vorhandene Paarbeziehung, andererseits zu einem entscheidenden Anteil durch mangelnde Gesundheit und Beckenbodenstorungen. Zu Beckenbodenstorungen gehoren Erkrankungen wie Harninkontinenz, Descensus genitalis, Blasenentleerungsstorungen oder Stuhlinkontinenz. Der Alterungsvorgang mit dem dadurch bedingten Verlust an Bindegewebe und Muskulatur sowie die vaginale Entbindung sind die beiden wichtigsten Ursachen fur eine symptomatische Beckenbodenstorung. Beckenbodenstorungen haben negativen Einfluss auf die Sexualfunktion der Frau im Senium. Konservative Behandlungsverfahren, wie Physiotherapie und lokale Ostrogenisierung, sollten unbedingt angeboten werden. Auch die Beckenbodenchirurgie zur Behandlung von Senkungs- und Inkontinenzerkrankungen kann sexuelle Funktionsstorungen beheben, ist aber nicht selten assoziiert mit einer negativen Beeinflussung der Erregungs- und Orgasmusphase. Levatorplastiken mit Muskelinterpositionen uber dem Rektum bzw. im Spatium rezii sowie die vaginale Fixatio sacrospinalis nach Amreich-Richter sollten der Vergangenheit angehoren. Auch grosflachige synthetische Netze zur Behandlung von Zystozele und Rektozele sollten speziell bei sexuell aktiven Frauen sehr streng indiziert werden. Urogynakologische Patientinnen sollten grundsatzlich bezuglich ihrer Sexualitat befragt werden.

In present study, the behavior of electrospun ZnO nanofibers under the application of low frequency alternating (AC) electric fields within the range of 1 Hz–20 kHz was investigated using planar parallel electrodes. In the first stage, ZnO nanofibers with diameters up to 100 nm were prepared by electrospinning. At 1 Hz, the strong electric field-induced fluid flow due to charge redistribution around the electrode swept the fibers on the electrode surface farther from the edges. As the frequency was increased to 1 kHz, most depositing fibers accumulated on the electrode edges and in the meantime, a small fraction of them was pushed into the surface as a result of AC electroosmosis effect. Above 1 kHz, the fibers were assembled within the electrode gap bridging the interelectrode space. The dielectrophoresis force was considered responsible for the assembly and relative alignment of ZnO nanofibers above 1 kHz.

Background Galanin participates in the pathogenesis of acute pancreatitis (AP). The galanin receptor (GALR) sub-types involved, however, are unclear. We aimed to determine GALRs messenger RNA (mRNA) expression in mouse pancreas, describe their localization, and ascertain if GALR2 and GALR3 are involved in AP. Methods Galanin receptor expression in murine whole pancreas, acinar, and islet cells was quantified by polymerase chain reaction amplification of reverse-transcribed RNA for mRNA, Western blot analysis for protein and in situ hybridization for GALR localization. Isolated acinar cells were used to determine galanin’s effect on amylase secretion. Acute pancreatitis was induced in mice by caerulein injections. Mice, with and without AP, were treated with the highly selective GALR2 antagonist M871, or the specific GALR3 antagonist SNAP-37889. Indices of AP were measured at 12 h. Key Results Murine pancreas expresses mRNA for GALRs. In islets the expression of all GALR are comparable, whereas in acinar cells GALR3 is predominantly expressed. Western blot analysis confirmed that the GALR proteins are expressed by acinar cells. In situ hybridization analysis confirmed that GALR3 mRNA is present in islet and acinar cells, while mRNA for GALR1 and 2 is confined to islets. Galanin did not influence basal and caerulein-stimulated amylase release from acinar cells. M871 treatment reduced some, whereas SNAP-37889 treatment reduced all indices of AP (by 40–80%). Conclusions & Inferences Galanin receptor mRNA and protein are expressed in mouse pancreas, with GALR3 mRNA predominating. GALR3 antagonism reduced the severity of AP whereas GALR2 antagonism was less effective. GALR3 is a potential target for treatment of AP.

The present study deals with the electrospinning preparation of a self-supporting nanofibrous membrane to be used for particle separation applications especially from aqueous media. Electrospun PAN nanofibrous mat with average fiber diameter of 165 ± 16 nm was prepared and employed as a membrane material for water filtration due to its high chemical and thermal stabilities and good wetability with water. The results obtained from SEM observations and Brunauer–Emmett–Teller (BET) technique indicated that the porosity of 91.7% and specific surface area near 40 m 2 g −1 along with open pores in the diameter range of less than 2 μm, have provided high permeability and low pressure drop, high dirt-loading capacity and an ability to retain small particles for the nanofibrous membrane. The membrane exhibited high water permeability and mechanical strength as a result of having high level of consistency with minimum number of structural defects. The evaluation of filtration behavior of the membrane with an aid of an optical particle counter proved that the membrane has high ability to remove more than 90% of microparticles in the range of 1–20 μm from water and possesses high quality factor.

A combination of the remarkably simple technique of electrospinning, developed to fabricate polymer nanofibers, and sol–gel processing has been utilized to produce fine zinc oxide nanofibers with an average diameter of 70 nm. A non-toxic precursor solution of polyvinyl alcohol and zinc acetate was electrospun and the resulting fibers were then calcined at a relatively low temperature to produce ZnO nanofibers. Simultaneous thermal analyses were used to study the formation of ZnO nanofibers from the precursor material. X-ray diffraction was employed to analyze the phases and different microscopy techniques, such as scanning electron microscopy, transmission electron microscopy and atomic force microscopy were used to study the morphology and size of the fibers. Fourier transform infrared spectroscopy was employed to investigate the composition of the precursor and ZnO fibers. The specific surface area of the electrospun nanofibers was determined using the Brunauer–Emmett–Teller method and optical properties were measured by UV-Vis and PL spectroscopy. The very high specific surface area of the ZnO fibers makes them potential candidates for nanodevice applications in gas sensing, dye-sensitized solar cells, and UV/blue emission devices.

Using a facile synthesis route, cadmium oxide (CdO) nanofibers in the diameter range of 50–60 nm have been prepared employing the electrospinning technique followed by a single-step calcination from the aqueous solution of polyvinyl alcohol (PVA) and cadmium acetate dihydrate. Electron microscopy (EM) and the Brunauer–Emmett–Teller (BET) technique were employed to characterize the as-spun nanofibers as well as the calcined product. The specific surface area of the product was calculated to be 42.6711 m 2 g −1 . Infrared (IR) absorbance spectroscopy and X-ray powder diffractometery were conducted on the samples to study their chemical composition as well as their crystallographic structure. The study on the optical properties based on the photoluminescence (PL) spectrum demonstrated that the emission peaks of CdO nanofibers are centered at 493 and 528 nm. The direct bandgap of the CdO nanofibers was determined to be 2.51 eV.

In this study, polyvinylidene fluoride (PVDF) membranes with various structures ranging from dense to highly asymmetric morphologies were obtained by changing the effective parameters in the phase inversion process. The effect of some important processing parameters such as solution concentration, harshness of the precipitation bath, exposure time before immersion in coagulation bath and bath temperature was studied and the mentioned parameters were optimized. The membranes were then modified with nano-sized alumina powder in order to improve the hydrophilicity of the PVDF membranes. The surface morphology, surface and cross-sectional structures of the membranes were examined by scanning electron microscope (SEM) and atomic force microscope (AFM). The specific surface area of the membranes was determined using the Brunauer–Emmett–Teller (BET) method. The contact angles between water and the membranes' surfaces were measured in order to study the hydrophilicity changes of the membrane surface. The results indicated that the addition of nano-sized alumina to the casting dope increased the hydrophilicity of the PVDF membrane surface.

A high density single-phase lead magnesium niobate ceramic with the highest peak dielectric constant reported so far, has been synthesized and sintered simultaneously via a modified mixed oxide route, using mixed oxide nanopowder and single-step sintering. The mixed nanopowder was sintered at 1200 °C in air and PbO atmospheres. By comparison, samples sintered in air, gained pyrochlore structure, while those samples sintered in PbO atmosphere had pure perovskite structure. Pellets sintered for 2.5 h exhibited best dielectric properties with peak dielectric constant of 18,672 at the frequency of 1 kHz at −13 °C. The dielectric properties, compressibility, phase formation, densification, and microstructure of the samples were investigated.

The past decade has seen VSC-HVDC systems deployed to establish transmission schemes both onshore and offshore, often for interconnectors utilizing underground or subsea cables but also a few systems designed to operate on long overhead transmission lines (OHTLs) [1]. In specific literature, it is referred to the capability of VSC schemes being able to feed power into passive AC grids, hence with a short-circuit capacity equal to zero. However, for proper AC grid operation, there are constraints and power transmission limitations, which come inherently from the physical nature of the AC systems on the receiving and sending ends of the power interconnector, related to their capability to keep stable operating voltage. This paper intends to examine this aspect in order to shed some light on the issue of power transmission limitations for VSC HVDC interconnectors as a function of AC grid characteristics.

The model of the machine layout problem MLP in a cellular manufacturing environment attains additional dimensions as it should satisfy the qualitative interconnections between the machines and the location restrictions of an existing factory environment. A new MLP model based on merging pre-emptive goal programming and simulated annealing has been developed for machine layout in cells. This model seeks to find feasible solutions by addressing practical issues of implementation as well as reducing the total travel distances for parts between machines. The new model can also be applied to facility layout problems FLP . The computational work is demonstrated by applying the model to problems of both quantitative and qualitative types, and has produced encouraging results. This model is particularly attractive for layout problems with realistic goals and constraints. To show the performance of the model in handling real-world problems, a practical example has been introduced and solved using the proposed model.

Effects of buffer salt concentration on the rate of deposition, dominated deposition mechanism and subsequently the structural, morphological, and optical properties of cadmium sulfide (CdS) thin films deposited by chemical bath deposition (CBD) on glass substrate were investigated. The precursors were chosen to be cadmium chloride (CdCl2) as the cadmium source, thiourea (CS(NH[Formula: see text]) as the sulfur source, ammonium nitrate (NH4NO3) as the buffer salt and ammonia as the complexing agent and the pH controller. The influence of the NH4NO3 concentration on the structure, morphology, film uniformity, stoichiometry and optical properties of CdS thin films was also studied by X-ray diffractometer (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX) spectroscope, uv–visible and photoluminescence (PL) spectroscopes. The XRD studies revealed that all the deposited films exhibited a (002)h/(111)c preferred orientation. The crystallite size was increased from 20[Formula: see text]nm to 30[Formula: see text]nm by the increase of concentration of NH4NO3 from 0.5[Formula: see text]M to 2.5[Formula: see text]M. The morphology of CdS thin films were agglomerated spherical particles consisted of smaller particles. The surface of thin films deposited at the NH4NO3 concentration of 0.5[Formula: see text]M was compact and smooth. The increase of the concentration of NH4NO3 decreased the packing density of the films. The optical band gap was in the range of 2.25–2.4[Formula: see text]eV, which was decreased by the decrement of packing density. The PL spectra showed two peaks centered at 400[Formula: see text]nm and 500[Formula: see text]nm which are attributed to violet and band-to-band emissions, respectively.

The application of Neural Network for disease diagnosis has made great progress and is widely used by physicians. An Electrocardiogram carries vital information about heart activity and physicians use this signal for cardiac disease diagnosis which was the great motivation towards our study. In our work, tachycardia features obtained are used for the training and testing of a Neural Network. In this study we are using Fuzzy Probabilistic Neural Networks as an automatic technique for ECG signal analysis. As every real signal recorded by the equipment can have different artifacts, we needed to do some preprocessing steps before feeding it to our system. Wavelet transform is used for extracting the morphological parameters of the ECG signal. The outcome of the approach for the variety of arrhythmias shows the represented approach is superior than prior presented algorithms with an average accuracy of about %95 for more than 7 tachy arrhythmias., {"references":["PHW. Leong, \"A Low Power VLSI Arrhythmia Clasifier\" in IEEE\nTransaction on neural networks, vol. 6,No 6, 1995, pp. 1435-1445.","Gari D. Clifford, Signal Processing Methods For Heart Rate Variability\nAnalysis, University of Oxford, 2002.","A.L. Goldberger, L.A.N Amaral, L. Glass, J.M. Hausdorff, P.Ch.\nIvanov, R.G. Mark, J.E. Mietus G.B. Moody, C.K.Peng, H.E. Stanley, PhysioBank, PhysioToolkit, and PhysioNet, Components of a New Research Resource for Complex Physiologic Signals, American Heart\nAssociation, 2000.","http://www.physionet.org/physiobank.","J Pan, WJ Tompkins, A real time QRS detection algorithm, Biomed Eng\nIEEE Trans, vol. 3,1985,pp. 230-236.","JP Sahoo, Analysis of ECG signal for detection of cardiac arrhythmias,\n2011.","A Graps, An Introduction to wavelets, Computation Science &\nEngineering IEEE, vol.2, 1995, pp. 50-61.","PS Addison, Wavelet transform and the ECG, Physiol, Meas 2005,pp.\n155-199.","I Daubechies, Ten Lectures on wavelets, SIAM, 1992.\n[10] M. Elgendi, R wave detection using coiflets wavelets, Bioengineering\nConference, IEEE 35th Annual Northeast, 2009.\n[11] V. Kecman, Learning and Soft Computing Support vector machines-\nNeural Networks-Fuzzy Logic, MIT, 2001.\n[12] DF Spetch, Probabilistic Neural Network, Neural Networks, vol. 3,\n1990, pp. 109-118.\n[13] HA Guvenir, B Acar, Feature Selection using a Genetic Algorithm for\nthe detection of abnormal ECG recordings, International Conference on\nMachine Learning,Florida, 2001.\n[14] W Zhu,N Zeng, N Wang, Sensitivity-Specificity-Accuracy Associated\nand ROC Analysis with practical SAS implementation,NEGUS,2010.\n[15] TM Nazmy, H El.Messiry, F Al-Bokhity, Adaptive Neuro-Fuzzy\nInference system for classification of ECG signals, Journal of\nTheoretical and Applied Information Technology, 2009.\n[16] F Belhachat, N Izoboudjen, Application of a probabilistic neural\nnetwork for classification of cardiac arrhythmias, 13th International Research/ Expert Conference\" Trends in the development of machineryand associated technology\", Tunisia, 2009.\n[17] D Gao, M Madden, Arrhythmia Identification from ECG Signals with a\nNeural Network Classifier Based on a Bayesian Framework, 24th SGAI\nInternational Conference on Innovative Techniques and Applications of\nArtificial Intelligence, 2004."]}

This paper discusses the application of Phasor Measurement Units (PMU's) to improve power system stability. The focus is on using PMU data to influence power system primary equipment and secondary controls to provide real time improvement. Modal analysis of PMU data from multiple locations is used to identify inter-area stability issues and local oscillation modes. Oscillatory stability monitoring techniques based on PMU data were validated against standard systems with known frequency components. A virtual PMU which includes IEEE C37.118 communication was created to be able to run in a PC environment. Key system stability metrics are presented to illustrate the effectiveness of the control actions. This paper also discusses the use of remote measurements to improve local power system stability. The paper specifically looks at improving the Power Oscillation Damping (POD) feature of HVDC technology through the use of remote measurements. The paper also looks at small signal stability issues and the improvement through Wide area measurements (WAM).

Galanin participates in the pathogenesis of acute pancreatitis (AP). The galanin receptor (GALR) sub-types involved, however, are unclear. We aimed to determine GALRs messenger RNA (mRNA) expression in mouse pancreas, describe their localization, and ascertain if GALR2 and GALR3 are involved in AP.Galanin receptor expression in murine whole pancreas, acinar, and islet cells was quantified by polymerase chain reaction amplification of reverse-transcribed RNA for mRNA, Western blot analysis for protein and in situ hybridization for GALR localization. Isolated acinar cells were used to determine galanin's effect on amylase secretion. Acute pancreatitis was induced in mice by caerulein injections. Mice, with and without AP, were treated with the highly selective GALR2 antagonist M871, or the specific GALR3 antagonist SNAP-37889. Indices of AP were measured at 12 h.Murine pancreas expresses mRNA for GALRs. In islets the expression of all GALR are comparable, whereas in acinar cells GALR3 is predominantly expressed. Western blot analysis confirmed that the GALR proteins are expressed by acinar cells. In situ hybridization analysis confirmed that GALR3 mRNA is present in islet and acinar cells, while mRNA for GALR1 and 2 is confined to islets. Galanin did not influence basal and caerulein-stimulated amylase release from acinar cells. M871 treatment reduced some, whereas SNAP-37889 treatment reduced all indices of AP (by 40-80%).Galanin receptor mRNA and protein are expressed in mouse pancreas, with GALR3 mRNA predominating. GALR3 antagonism reduced the severity of AP whereas GALR2 antagonism was less effective. GALR3 is a potential target for treatment of AP.

This paper develops a novel hybrid intelligent method, which is combined Petri Net (PN) model with Ant Colony Optimization (ACO) to solve target network reconfiguration strategy for power system restoration. The target network is firstly modeled by Petri Net (PN) theory. In order to find the shortest restored energized path effectively, the transition rules of PN and the ACO algorithm are integrated elaborately. Finally, the case studies for IEEE 30-bus system as benchmark are applied to demonstrate the validity and effectiveness of the proposed model and method. (4 pages)

In this paper we conduct a feasibility study using simulation for AirTran Airways at their hub in Atlanta Hartsfield-Jackson International Airport (ATL). This study pertains to using super-tug to transport aircraft to and from the airline's maintenance facility. The purchasing price for these super-tugs is around a quarter of a million dollars. This study attempts to investigate the possibility of reducing costs through saving jet fuel. This study adopts simulation to analyze the annual savings by studying the numbers needed, as well as the utilization and operation cost for these super-tugs. The results are very interesting, enabling the airline to clearly evaluate the cost and benefits of purchasing new super-tugs.

Valveless piezoelectric micropumps are in wide practical use due to their ability to conduct particles with absence of interior moving mechanical parts. The objective of this paper is to obtain the fluid flow response to actuation frequency of a passive diffuser valve under harmonic pressures. In this regards a 2D model of a micropump valves and chambers is analyzed. The analysis is performed for 10Kpa back pressure on micropump chamber and actuation frequencies within the range of 1Hz to 10 KHz. Results show the highest velocity in the direction of diffuser axis occurs at the narrow diffuser neck while flow direction reverses every half period. For low frequencies, a parabolic velocity profile is observed at the valve midway while, instabilities with the tendency of transition to boundary layer dominant profile is observed for high actuation frequencies. Oscillating flow in diffuser indicates existence of high shear stress regions near the wall along with the flow reversal in the center at high frequencies. Both valve and pump net flow rate decrease drastically as the frequency approaches a certain value. From electrical analogy viewpoint, nozzle/diffuser passive valves can be modeled as Low Pass Filters (LPF). The results are in good agreement with the relevant analytical findings. Similar to analytical results, flow rate is approximately in phase with actuation at low frequencies but phase shift ascends as actuation frequency is increased. The main head loss of flow occurs at the diffuser valves while sudden contraction and expansion of streamlines at the diffuser entrance and exit involve only 22% of the total energy. The results are in agreement with the previous experiments of micropump flow at high frequencies.Copyright © 2006 by ASME

This exploratory study examined the impact of physician recommendations and other factors on mammography screening and breast-self examination (BSE) among African American and Hispanic women in public housing communities. We surveyed a randomly selected sample of low-income households from three low-income communities (n = 291), which included both African Americans and Hispanic women. Data for this paper are reported only on women who were 40 years and older head of the households (n = 120 women, including 74 Hispanics and 46 African Americans), since they meet the age criterion for mammography screening. Our analyses indicated that only 46% of women obtained mammography in the previous 12 months, with no significant differences between the Hispanic and African American women in mammography rates. Physicians' recommendations were among the most significant and substantial predictors of obtaining a mammogram or performing BSE. Further, odds were also higher for those who had insurance coverage. In addition, our data also indicated that almost one out of four women, aged 40 and older participants in this study, claimed that their health care providers never told them they needed a mammogram or never told them that they should perform BSE, with no significant differences between Hispanic and African Americans. Our analyses points to an urgent need for intervention to inform and motivate the service providers in underserved communities to motivate breast cancer screening (BCS) among minority women. Additionally, our examination points to the need for urgent interventions targeting minority women, particularly women with no medical insurance for breast cancer screening.

This paper reports results of research that developed a computerized simulation model for the aircraft line maintenance department in Continental Airlines. The original AUTOMOD model that was created duplicated the maintenance operations at Continental's major maintenance station at Newark. Modeling the day-to-day maintenance activities lead to the development of enhanced staffing models and a better understanding of resource requirements on a daily basis. This study had immediate and practical application as well as advancing an important frontier in operations research. Simulation modeling was effectively used in the estimation of technician requirements on a subshift basis. Simulation modeling generated performance measures, like technician utilization and work overflow, which could not be estimated earlier. The model gave objective justification for simple solutions like staggered shifts and part-time labor, which can meet resistance in a workforce. Simulation offers a viable tool for studying the impact of changing flight schedule on system parameters, like technician requirements. The optimization studies showed that changing the shift schedule could greatly enhance the efficiency of the existing system by spreading the workload more uniformly across shifts. Simulation, especially stochastic simulation, has advantages over mathematical modeling, especially in situations where flows have an apparent randomness in their character. Airline maintenance operations, and many maintenance operations in general, are plagued by planning difficulties because failures seem random at high levels of analysis, and/or because scheduling is tightly coupled with (and slaved to) other operations which are erstwhile irregular in their natures. Airline maintenance is one of the most important applications of maintenance in industry, as it has a profound impact on cost, customer satisfaction, and safety. This study applied stochastic modeling to flightline maintenance at an important airline, and illustrated the opportunity for improved maintenance management that only hints of its overall potential.

We examined the prevalence of alcohol, tobacco, and drug use and their relation to the age of onset of type 2 diabetes among inner-city minority diabetic patients who sought routine care at medical clinics in south central Los Angeles.A cross-sectional study design was used to sample 392 diabetic patients. Consecutive patients from seven different primary care clinics were interviewed to determine their alcohol, tobacco, and drug use histories and the age of onset of diabetes.The study sample was 61% Hispanic and 64% female and had a mean age of 53 years. Seventy-one diabetic patients (18%) reported that they recently consumed alcohol. Sixty-nine patients (17%) reported smoking within 30 days of their interview. Thirty-eight diabetic patients reported a history of regular illicit drug use. Multiple regression analysis showed that diabetic patients who used alcohol, illicit drugs, or combined substances (alcohol and illicit drugs), but not tobacco alone, reported an earlier onset of type 2 diabetes.This hypothesis-generating study suggests that alcohol and illicit drugs, when used alone or in combination, might be associated with an earlier onset of type 2 diabetes. Additional research, however, is required to evaluate further these preliminary findings.

This study was designed to examine the effect of 500 to 5,000 mg of ascorbic acid on DNA adducts, natural killer (NK) cell activity, programmed cell death, and cell cycle analysis of human peripheral blood leukocytes. According to our hypothesis, if ascorbic acid is a pro-oxidant, doses between 500 and 5,000 mg should enhance DNA adduct formation, decrease immune function, change the cell cycle progression, and increase the rate of apoptosis. Twenty healthy volunteers were divided into four groups and given either placebo or daily doses of 500, 1,000 or 5,000 mg of ascorbic acid for a period of 2 weeks. On days 0, 1, 7, 15, and 21, blood was drawn from them, and the leukocytes were separated and examined for intracellular levels of ascorbic acid, the level of 8-hydroxyguanosine, NK cell activity, cell cycle progression, and apoptosis. Depending on the subjects, between a 0% and a 40% increase in cellular absorption of ascorbic acid was observed when daily doses of 500 mg were used. At doses greater than 500 mg, this cellular absorption was not increased further, and all doses produced equivalent increases in ascorbic acid on days 1 to 15. This increase in cellular concentration of ascorbic acid resulted in no statistically meaningful changes in the level of 8-hydroxyguanosine, increased NK cytotoxic activity, a reduced percentage of cells undergoing apoptosis, and switched cell cycle phases from S and G2/M to G0/G1. After a period of 1 week, with no placebo or vitamin washout, ascorbic acid levels along with functional assays returned to the baseline and became equivalent to placebos. In comparison with baseline values, no change (not more than daily assays variation) was seen in ascorbate concentrations or other assays during oral placebo treatment. We concluded that ascorbic acid is an antioxidant and that doses up to 5,000 mg neither induce mutagenic lesions nor have negative effects on NK cell activity, apoptosis, or cell cycle.

This study identifies theoretically based predictors of condom use in a sample of 253 sexually active African-American college students recruited from two historically African-American colleges. The Information-Motivation-Behavioral (IMB) skills model of AIDS-preventive behavior was employed to delineate the roles of HIV/AIDS knowledge, experiences with and attitudes toward condom use, peer influences, perceived vulnerability, monogamy, and behavioral skills. A predictive structural equation model revealed significant predictors of more condom use including: male gender, more sexual HIV knowledge, positive experiences and attitudes about condom use, nonmonogamy, and greater behavioral skills. Results imply that attention to behavioral skills for negotiating safer sex and training in the proper use of condoms are key elements in reducing high risk behaviors. Increasing the specific knowledge level of college students regarding the subtleties of sexual transmission of HIV is important and should be addressed. Heightening students' awareness of the limited protection of serial monogamy, and the need to address gender-specific training regarding required behavior change to reduce transmission of HIV should be an additional goal of college health professionals.

Little is known about the reading habits of family practice residents. This study describes the reading practices of family practice residents, including how much time they spend reading and what information sources they use, identifies factors that may be used by educators to stimulate resident reading, and identifies factors that may inhibit or discourage reading.A questionnaire about reading habits was mailed to 613 randomly selected resident members of the American Academy of Family Physicians in March 1994.Of 613 questionnaires sent, 314 (51%) were completed and returned. Participants reported reading an average of 3.7 hours per week and were most often motivated to read to obtain information related to clinical cases or to prepare for an upcoming presentation. Pocket manuals were the most frequently read and original scientific research the least frequently read sources of medical information. Fatigue and family responsibilities were the factors most important in preventing reading. Year in residency, moonlighting hours, age, gender, or household size were not associated with reported reading time.Clinical cases and upcoming presentations may be the best motivators of resident reading. Training programs need to continue to develop strategies to minimize resident fatigue, which may lead to increased reading among trainees. The importance of original scientific research articles during residency training is unclear.