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Sample records for maximum transmitted current

  1. Transmit-receive eddy current probes

    International Nuclear Information System (INIS)

    Obrutsky, L.S.; Sullivan, S.P.; Cecco, V.S.

    1997-01-01

    In the last two decades, due to increased inspection demands, eddy current instrumentation has advanced from single-frequency, single-output instruments to multifrequency, computer-aided systems. This has significantly increased the scope of eddy current testing, but, unfortunately, it has also increased the cost and complexity of inspections. In addition, this approach has not always improved defect detectability or signal-to-noise. Most eddy current testing applications are still performed with impedance probes, which have well known limitations. However, recent research at AECL has led to improved eddy current inspections through the design and development of transmit-receive (T/R) probes. T/R eddy current probes, with laterally displaced transmit and receive coils, present a number of advantages over impedance probes. They have improved signal-to-noise ratio in the presence of variable lift-off compared to impedance probes. They have strong directional properties, permitting probe optimization for circumferential or axial crack detection, and possess good phase discrimination to surface defects. They can significantly increase the scope of eddy current testing permitting reliable detection and sizing of cracks in heat exchanger tubing as well as in welded areas of both ferritic and non-ferromagnetic components. This presentation will describe the operating principles of T/R probes with the help of computer-derived normalized voltage diagrams. We will discuss their directional properties and analyze the advantages of using single and multiple T/R probes over impedance probes for specific inspection cases. Current applications to surface and tube testing and some typical inspection results will be described. (author)

  2. Maximum time-dependent space-charge limited diode currents

    Energy Technology Data Exchange (ETDEWEB)

    Griswold, M. E. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Fisch, N. J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

    2016-01-15

    Recent papers claim that a one dimensional (1D) diode with a time-varying voltage drop can transmit current densities that exceed the Child-Langmuir (CL) limit on average, apparently contradicting a previous conjecture that there is a hard limit on the average current density across any 1D diode, as t → ∞, that is equal to the CL limit. However, these claims rest on a different definition of the CL limit, namely, a comparison between the time-averaged diode current and the adiabatic average of the expression for the stationary CL limit. If the current were considered as a function of the maximum applied voltage, rather than the average applied voltage, then the original conjecture would not have been refuted.

  3. Pharmacist-led screening in sexually transmitted infections: current perspectives

    Directory of Open Access Journals (Sweden)

    Wood H

    2018-06-01

    Full Text Available Helen Wood, Sajni Gudka School of Allied Health, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, WA, Australia Introduction: Sexually transmitted infection (STI screening is a crucial initiative that aims to reduce the increasing global prevalence of many common STIs such as chlamydia, gonorrhea, and herpes simplex virus (HSV. Many STIs are either asymptomatic or show mild symptoms that are often attributed to other infections; hence, screening is the only way to identify – and by extension, treat – them. In this way, the spread of STIs can be reduced, and the health implications of an untreated STI are minimized. Community pharmacies could provide an avenue to convenient, confidential STI screening by using noninvasive or minimally invasive sample collection techniques that are used by the consumer or pharmacist. We identified the most common STIs found globally and investigated the current and potential role of pharmacists in provision of STI screening interventions.Discussion: There is sufficient evidence for pharmacy-based chlamydia screening, with many consumers and pharmacists finding it an acceptable and highly valued service. Some evidence was found for pharmacy-based gonorrhea, hepatitis B virus (HBV, and human immunodeficiency virus (HIV screening. Appropriate sample collection for gonorrhea screening needs to be further examined in a pharmacy setting. HBV screening presented an increased risk of personal injury to pharmacists through the collection of whole blood specimens, which could be reduced through consumer self-sampling. Pharmacist-collected specimens for HIV is less risky as an oral swab can be used, nullifying the risk of transmission; but pre- and post-screen consultations can be time-intensive; hence, pharmacists would require remuneration to provide an ongoing HIV screening service. Not enough evidence was found for syphilis screening through community pharmacies; more studies are

  4. A maximum power point tracking for photovoltaic-SPE system using a maximum current controller

    Energy Technology Data Exchange (ETDEWEB)

    Muhida, Riza [Osaka Univ., Dept. of Physical Science, Toyonaka, Osaka (Japan); Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Park, Minwon; Dakkak, Mohammed; Matsuura, Kenji [Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Tsuyoshi, Akira; Michira, Masakazu [Kobe City College of Technology, Nishi-ku, Kobe (Japan)

    2003-02-01

    Processes to produce hydrogen from solar photovoltaic (PV)-powered water electrolysis using solid polymer electrolysis (SPE) are reported. An alternative control of maximum power point tracking (MPPT) in the PV-SPE system based on the maximum current searching methods has been designed and implemented. Based on the characteristics of voltage-current and theoretical analysis of SPE, it can be shown that the tracking of the maximum current output of DC-DC converter in SPE side will track the MPPT of photovoltaic panel simultaneously. This method uses a proportional integrator controller to control the duty factor of DC-DC converter with pulse-width modulator (PWM). The MPPT performance and hydrogen production performance of this method have been evaluated and discussed based on the results of the experiment. (Author)

  5. Effect of current on the maximum possible reward.

    Science.gov (United States)

    Gallistel, C R; Leon, M; Waraczynski, M; Hanau, M S

    1991-12-01

    Using a 2-lever choice paradigm with concurrent variable interval schedules of reward, it was found that when pulse frequency is increased, the preference-determining rewarding effect of 0.5-s trains of brief cathodal pulses delivered to the medial forebrain bundle of the rat saturates (stops increasing) at values ranging from 200 to 631 pulses/s (pps). Raising the current lowered the saturation frequency, which confirms earlier, more extensive findings showing that the rewarding effect of short trains saturates at pulse frequencies that vary from less than 100 pps to more than 800 pps, depending on the current. It was also found that the maximum possible reward--the magnitude of the reward at or beyond the saturation pulse frequency--increases with increasing current. Thus, increasing the current reduces the saturation frequency but increases the subjective magnitude of the maximum possible reward.

  6. Current opinion about maximum entropy methods in Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Szymanski, K

    2009-01-01

    Current opinion about Maximum Entropy Methods in Moessbauer Spectroscopy is presented. The most important advantage offered by the method is the correct data processing under circumstances of incomplete information. Disadvantage is the sophisticated algorithm and its application to the specific problems.

  7. The maximum and minimum values of the heat Q transmitted from metal to boiling water under atmospheric pressure

    International Nuclear Information System (INIS)

    Nukiyama, S.

    1991-01-01

    The quantity of heat transmitted from a metal surface to boiling water increases as the temperature difference ΔT is increased, but after the ΔT has reached a certain limit, quantity Q decreases with further increase in ΔT. This turning point is the maximum value of heat transmitted. The existence of this point was actually observed in the experiment. Under atmospheric pressure, ΔT corresponding to the maximum value of heat transfer for water at 100 degrees C falls between 20-40 degrees C, and Q is between 1,080,000 and 1,800,000 kcal/m 2 h (i.e. between 2,000 and 3,000 kg/m 2 h, if expressed in constant evaporation rate at 100 degrees C); this figure is larger than the maximum value of heat transfer as was previously considered. In this paper the minimum value of heat transfer was obtained, and in the Q-ΔT curve for the high temperature region, the burn-out effect is discussed

  8. [Sexually transmitted infections in Germany : The current epidemiological situation].

    Science.gov (United States)

    Bremer, Viviane; Dudareva-Vizule, Sandra; Buder, Susanne; An der Heiden, Matthias; Jansen, Klaus

    2017-09-01

    Sexually transmitted infections (STIs) can impair sexual health. Surveillance and study data were used to provide an overview over STIs in Germany. We estimated 3900 new HIV diagnoses in 2015. Of newly diagnosed infections, 57% were attributed to men who have sex with men (MSM). It was further estimated that there were 3200 new HIV infections and 84,700 people living with HIV in 2015. A total of 6834 syphilis infections were recorded in 2015, which corresponds to an increase of 149% since 2009. The incidence in men was 16-times higher than in women. Of syphilis infections, 85% could be attributed to MSM. Antimicrobial resistance of gonococci against the broad-spectrum antibiotic cefixime decreased between 2014 and 2016 after a change of therapy guidelines and remained stable on a low level regarding the antibiotic ceftriaxone. After an increase of resistance against the antibiotic azithromycin to 11.3% in 2015, we observed a decreasing trend in 2016. Between 2013 and 2015, 2,355,336 chlamydia tests were reported through the chlamydia sentinel network. Of these, 92.5% of samples were from women. Uptake for screening for women human papilloma virus (HPV) of 38.1% was observed. A total of 30.5% of 15-year-old women were vaccinated against HPV in 2014. Data suggest that STIs represent a high burden of disease. Knowledge of STI prevention should be improved by targeted education campaigns. Extending existing offers for counselling and testing through cooperation between different health sectors would improve early diagnosis and treatment of STIs.

  9. Eddy Current Signal Analysis for Transmit-Receive Pancake Coil on ECT Array Probe

    International Nuclear Information System (INIS)

    Lee, Hyang Beom

    2006-01-01

    In this paper, the eddy current signals come from a pair of transmit-receive (T/R) pancake coil on ECT array Probe are analyzed with the variations of the lift-of and of the distance between transmit and receive coils. To obtain the electromagnetic characteristics of the probes, the governing equation describing the eddy current problems is derived from Maxwell's equation and is solved using three-dimensional finite element method. Eddy current signals from T/R coils on ECT array probe have quite different characteristics compared with ones from impedance coil on rotating pancake coil probe. The results in this paper ran be helpful when the field eddy current signals from ECT array probe are evaluated

  10. [Current situation of soil-transmitted nematodiasis monitoring in China and working keys in future].

    Science.gov (United States)

    Chen, Ying-dan; Zang, Wei

    2015-04-01

    Soil-transmitted nematodiasis is widely epidemic in rural areas in China. It was showed that the infection rate of soil-transmitted nematodes was 19.56% while the overall number of persons infected was 129,000,000, which was supported by the results of the National Survey of Current Situation of Major Human Parasitic Diseases in China in 2005 published by former Ministry of Health. Therefore, soil-transmitted nematodiasis was included in the national infectious diseases and pathogenic media monitoring system by Chinese Center for Disease Control and Prevention in 2006, and subsequently 22 monitoring spots were established nationwide. From 2006 to 2013, the human infection rate of intestinal nematodes in national monitoring spots decreased from 20.88% to 3.12%, which showed a declining trend year by year. Meanwhile, the infection rates of Ascaris lumbricoides, Trichuris trichiura, hookworm, Enterobius vermicularis decreased from 10.10%, 5.88%, 8.88%, 10.00% in 2006 to 0.76%, 0.42%, 2.04%, 6.78% in 2013 respectively. In this paper, the current situation of soil-transmitted nematodiasis is overviewed based on a summary of the 8 years' monitoring work, as well as the experiences, challenges and key of monitoring work in the future.

  11. Current strategies and future directions for the prevention of transfusion-transmitted cytomegalovirus

    Directory of Open Access Journals (Sweden)

    Harmon CM

    2017-04-01

    Full Text Available Charles M Harmon, Laura L Cooling Department of Pathology, University of Michigan, Ann Arbor, MI, USA Abstract: Cytomegalovirus (CMV is a pervasive DNA virus that infects a significant portion of individuals worldwide, and may be transmitted through the transfusion of blood products. Although CMV infection is of little consequence in immunocompetent individuals, patients with an impaired immune system are at risk of significant morbidity and mortality. Unlike other blood-borne infectious agents, it is impractical to defer all CMV-positive individuals from blood donation as this would exclude a substantial number of otherwise eligible donors. Other methods such as transfusion of CMV-seronegative and leukoreduced blood products must be employed to prevent the transmission of CMV to at-risk patients. In this study, the widespread use of current strategies for the prevention of transfusion-transmitted CMV (TT-CMV infection and the evidence to support these methods in various at-risk groups were reviewed. In addition, emerging pathogen inactivation technologies that have the potential to eliminate TT-CMV were also discussed. Keywords: blood transfusion, cytomegalovirus, leukoreduction, pathogen inactivation, hematopoietic stem cell transplantation, very low birth weight infants

  12. A 16-channel receive, forced current excitation dual-transmit coil for breast imaging at 7T.

    Directory of Open Access Journals (Sweden)

    Samantha By

    Full Text Available To enable high spatial and temporal breast imaging resolution via combined use of high field MRI, array coils, and forced current excitation (FCE multi channel transmit.A unilateral 16-channel receive array insert was designed for use in a transmit volume coil optimized for quadrature operation with dual-transmit RF shimming at 7 T. Signal-to-noise ratio (SNR maps, g-factor maps, and high spatial and temporal resolution in vivo images were acquired to demonstrate the utility of the coil architecture.The dual-transmit FCE coil provided homogeneous excitation and the array provided an increase in average SNR of 3.3 times (max 10.8, min 1.5 compared to the volume coil in transmit/receive mode. High resolution accelerated in vivo breast imaging demonstrated the ability to achieve isotropic spatial resolution of 0.5 mm within clinically relevant 90 s scan times, as well as the ability to perform 1.0 mm isotropic resolution imaging, 7 s per dynamics, with the use of bidirectional SENSE acceleration of up to R = 9.The FCE design of the transmit coil easily accommodates the addition of a sixteen channel array coil. The improved spatial and temporal resolution provided by the high-field array coil with FCE dual-channel transmit will ultimately be beneficial in lesion detection and characterization.

  13. Maximum power point tracking for PV systems under partial shading conditions using current sweeping

    International Nuclear Information System (INIS)

    Tsang, K.M.; Chan, W.L.

    2015-01-01

    Highlights: • A novel approach for tracking the maximum power point of photovoltaic systems. • Able to handle both the uniform insolation and partial shading conditions. • Maximum power point tracking based on current sweeping. - Abstract: Partial shading on photovoltaic (PV) arrays causes multiple peaks on the output power–voltage characteristic curve and local searching technique such as perturb and observe (P&O) method could easily fail in searching for the global maximum. Moreover, existing global searching techniques are still not very satisfactory in terms of speed and implementation complexity. In this paper, a fast global maximum power point (MPPT) tracking method which is using current sweeping for photovoltaic arrays under partial shading conditions is proposed. Unlike conventional approach, the proposed method is current based rather than voltage based. The initial maximum power point will be derived based on a current sweeping test and the maximum power point can be enhanced by a finer local search. The speed of the global search is mainly governed by the apparent time constant of the PV array and the generation of a fast current sweeping test. The fast current sweeping test can easily be realized by a DC/DC boost converter with a very fast current control loop. Experimental results are included to demonstrate the effectiveness of the proposed global searching scheme

  14. 30 CFR 75.601-3 - Short circuit protection; dual element fuses; current ratings; maximum values.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection; dual element fuses... Trailing Cables § 75.601-3 Short circuit protection; dual element fuses; current ratings; maximum values. Dual element fuses having adequate current-interrupting capacity shall meet the requirements for short...

  15. Current control of PMSM based on maximum torque control reference frame

    Science.gov (United States)

    Ohnuma, Takumi

    2017-07-01

    This study presents a new method of current controls of PMSMs (Permanent Magnet Synchronous Motors) based on a maximum torque control reference frame, which is suitable for high-performance controls of the PMSMs. As the issues of environment and energy increase seriously, PMSMs, one of the AC motors, are becoming popular because of their high-efficiency and high-torque density in various applications, such as electric vehicles, trains, industrial machines, and home appliances. To use the PMSMs efficiently, a proper current control of the PMSMs is necessary. In general, a rotational coordinate system synchronizing with the rotor is used for the current control of PMSMs. In the rotating reference frame, the current control is easier because the currents on the rotating reference frame can be expressed as a direct current in the controller. On the other hand, the torque characteristics of PMSMs are non-linear and complex; the PMSMs are efficient and high-density though. Therefore, a complicated control system is required to involve the relation between the torque and the current, even though the rotating reference frame is adopted. The maximum torque control reference frame provides a simpler way to control efficiently the currents taking the torque characteristics of the PMSMs into consideration.

  16. Influence of epoxy resin as encapsulation material of silicon photovoltaic cells on maximum current

    Directory of Open Access Journals (Sweden)

    Acevedo-Gómez David

    2017-01-01

    Full Text Available This work presents an analysis about how the performance of silicon photovoltaic cells is influenced by the use of epoxy resin as encapsulation material with flat roughness. The effect of encapsulation on current at maximum power of mono-crystalline cell was tested indoor in a solar simulator bench at 1000 w/m² and AM1.5G. The results show that implementation of flat roughness layer onto cell surface reduces the maximum current inducing on average 2.7% less power with respect to a cell before any encapsulation. The losses of power and, in consequence, the less production of energy are explained by resin light absorption, reflection and partially neutralization of non-reflective coating.

  17. Speed Control Analysis of Brushless DC Motor Based on Maximum Amplitude DC Current Feedback

    Directory of Open Access Journals (Sweden)

    Hassan M.A.A.

    2014-07-01

    Full Text Available This paper describes an approach to develop accurate and simple current controlled modulation technique for brushless DC (BLDC motor drive. The approach is applied to control phase current based on generation of quasi-square wave current by using only one current controller for the three phases. Unlike the vector control method which is complicated to be implemented, this simple current modulation technique presents advantages such as phase currents are kept in balance and the current is controlled through only one dc signal which represent maximum amplitude value of trapezoidal current (Imax. This technique is performed with Proportional Integral (PI control algorithm and triangular carrier comparison method to generate Pulse Width Modulation (PWM signal. In addition, the PI speed controller is incorporated with the current controller to perform desirable speed operation of non-overshoot response. The performance and functionality of the BLDC motor driver are verified via simulation by using MATLAB/SIMULINK. The simulation results show the developed control system performs desirable speed operation of non-overshoot and good current waveforms.

  18. A Survey of Current Knowledge on Sexually Transmitted Diseases and Sexual Behaviour in Italian Adolescents.

    Science.gov (United States)

    Drago, Francesco; Ciccarese, Giulia; Zangrillo, Francesca; Gasparini, Giulia; Cogorno, Ludovica; Riva, Silvia; Javor, Sanja; Cozzani, Emanuele; Broccolo, Francesco; Esposito, Susanna; Parodi, Aurora

    2016-04-13

    Worldwide, 500 million people a year acquire a sexually transmitted disease (STD). Adolescents, accounting for 25% of the sexually active population, are the most affected. To analyze sexual behavior among Italian adolescents and their knowledge of STDs, with the goal of preventing their transmission, a questionnaire was administered to 2867 secondary school students (1271 males and 1596 females) aged 14-21 years. For the study, 1492 students were interviewed in Genoa (Northern Italy) and 1375 in Lecce (Southern Italy). For 37% of the respondents, parents and teachers were the main source of information on sex, and 95% believed that school should play the primary role in sex education. However, only 9% considered the sex education they received in school good. Noteworthy, only 0.5% of the teenagers recognized the sexually transmitted diseases from a list of diseases, and 54% of them did not know what a Pap test was. Confusion about the meaning of contraception and prevention was evident; only 22% knew that condoms and abstinence are the only methods for preventing STDs. Finally, a consistent number of students are exposed to risk factors for STDs transmission; e.g., alcohol and recreational drug use, promiscuity and improper condom use. On the basis of our study, there is an urgent need for the introduction of sex education as a proper subject in Italian schools.

  19. A Survey of Current Knowledge on Sexually Transmitted Diseases and Sexual Behaviour in Italian Adolescents

    Directory of Open Access Journals (Sweden)

    Francesco Drago

    2016-04-01

    Full Text Available Worldwide, 500 million people a year acquire a sexually transmitted disease (STD. Adolescents, accounting for 25% of the sexually active population, are the most affected. To analyze sexual behavior among Italian adolescents and their knowledge of STDs, with the goal of preventing their transmission, a questionnaire was administered to 2867 secondary school students (1271 males and 1596 females aged 14–21 years. For the study, 1492 students were interviewed in Genoa (Northern Italy and 1375 in Lecce (Southern Italy. For 37% of the respondents, parents and teachers were the main source of information on sex, and 95% believed that school should play the primary role in sex education. However, only 9% considered the sex education they received in school good. Noteworthy, only 0.5% of the teenagers recognized the sexually transmitted diseases from a list of diseases, and 54% of them did not know what a Pap test was. Confusion about the meaning of contraception and prevention was evident; only 22% knew that condoms and abstinence are the only methods for preventing STDs. Finally, a consistent number of students are exposed to risk factors for STDs transmission; e.g., alcohol and recreational drug use, promiscuity and improper condom use. On the basis of our study, there is an urgent need for the introduction of sex education as a proper subject in Italian schools.

  20. Transfusion-transmitted CMV infection - current knowledge and future perspectives.

    Science.gov (United States)

    Ziemann, M; Thiele, T

    2017-08-01

    Transmission of human cytomegalovirus (CMV) via transfusion (TT-CMV) may still occur and remains a challenge in the treatment of immunocompromised CMV-seronegative patients, e.g. after stem cell transplantation, and for low birthweight infants. Measures to reduce the risk of TT-CMV have been evaluated in clinical studies, including leucocyte depletion of cellular blood products and/or the selection of CMV-IgG-negative donations. Studies in large blood donor cohorts indicate that donations from newly CMV-IgG-positive donors should bear the highest risk for transmitting CMV infections because they contain the highest levels of CMV-DNA, and early CMV antibodies cannot neutralise CMV. Based on this knowledge, rational strategies to reduce the residual risk of TT-CMV using leucoreduced blood products could be designed. However, there is a lack of evidence that CMV is still transmitted by transfusion of leucoreduced units. In low birthweight infants, most (if not all) CMV infections are caused by breast milk feeding or congenital transmission rather than by transfusion of leucoreduced blood products. For other patients at risk, no definitive data exist about the relative importance of alternative transmission routes of CMV compared to blood transfusion. As a result, only the conduction of well-designed studies addressing strategies to prevent TT-CMV and the thorough examination of presumed cases of TT-CMV will achieve guidance for the best transfusion regimen in patients at risk. © 2017 British Blood Transfusion Society.

  1. Use of the Maximum Torque Sensor to Reduce the Starting Current in the Induction Motor

    Directory of Open Access Journals (Sweden)

    Muchlas

    2010-03-01

    Full Text Available Use of the maximum torque sensor has been demonstrated able to improve the standard ramp-up technique in the induction motor circuit system. The induction motor used was of a three-phase squirrel-cage motor controlled using a microcontroller 68HC11. From the simulation done, it has been found that this innovative technique could optimize the performance of motor by introducing low stator current and low power consumption over the standard ramp-up technique.

  2. Maximum Bandwidth Enhancement of Current Mirror using Series-Resistor and Dynamic Body Bias Technique

    Directory of Open Access Journals (Sweden)

    V. Niranjan

    2014-09-01

    Full Text Available This paper introduces a new approach for enhancing the bandwidth of a low voltage CMOS current mirror. The proposed approach is based on utilizing body effect in a MOS transistor by connecting its gate and bulk terminals together for signal input. This results in boosting the effective transconductance of MOS transistor along with reduction of the threshold voltage. The proposed approach does not affect the DC gain of the current mirror. We demonstrate that the proposed approach features compatibility with widely used series-resistor technique for enhancing the current mirror bandwidth and both techniques have been employed simultaneously for maximum bandwidth enhancement. An important consequence of using both techniques simultaneously is the reduction of the series-resistor value for achieving the same bandwidth. This reduction in value is very attractive because a smaller resistor results in smaller chip area and less noise. PSpice simulation results using 180 nm CMOS technology from TSMC are included to prove the unique results. The proposed current mirror operates at 1Volt consuming only 102 µW and maximum bandwidth extension ratio of 1.85 has been obtained using the proposed approach. Simulation results are in good agreement with analytical predictions.

  3. Maximum likelihood estimation of biophysical parameters of synaptic receptors from macroscopic currents

    Directory of Open Access Journals (Sweden)

    Andrey eStepanyuk

    2014-10-01

    Full Text Available Dendritic integration and neuronal firing patterns strongly depend on biophysical properties of synaptic ligand-gated channels. However, precise estimation of biophysical parameters of these channels in their intrinsic environment is complicated and still unresolved problem. Here we describe a novel method based on a maximum likelihood approach that allows to estimate not only the unitary current of synaptic receptor channels but also their multiple conductance levels, kinetic constants, the number of receptors bound with a neurotransmitter and the peak open probability from experimentally feasible number of postsynaptic currents. The new method also improves the accuracy of evaluation of unitary current as compared to the peak-scaled non-stationary fluctuation analysis, leading to a possibility to precisely estimate this important parameter from a few postsynaptic currents recorded in steady-state conditions. Estimation of unitary current with this method is robust even if postsynaptic currents are generated by receptors having different kinetic parameters, the case when peak-scaled non-stationary fluctuation analysis is not applicable. Thus, with the new method, routinely recorded postsynaptic currents could be used to study the properties of synaptic receptors in their native biochemical environment.

  4. Sexually transmitted infections in India: Current status (except human immunodeficiency virus/acquired immunodeficiency syndrome

    Directory of Open Access Journals (Sweden)

    Thappa Devinder

    2007-01-01

    Full Text Available Sexually transmitted infections (STIs are more dynamic than other infections prevailing in the community. It is important that such dynamic epidemiological changes in STIs are acknowledged and kept track of in a vast and populous developing country like India, particularly in this HIV era. It is with this aim that the authors have reviewed the relevant literature in STI epidemiology in India during the past 25 years. Admittedly, there has been heterogeneity of data to account for the subcontinental dimension of this country. But a basic pattern in the changing epidemiology is discernible. Like the developed countries, in India too the bacterial STIs like chancroid and gonorrhea are declining, while viral STIs like HPV and herpes genitalis are on an upswing. The overall decline in the prevalence of STIs has to be interpreted with caution, however. This may partially reflect the improved facilities of treatment in the peripheral centres that obviates the need of many patients in attending the STD clinics in the tertiary centres. Also, the improved pharmacotherapy of many of the bacterial STIs may result in partial clearance and non-reporting of many of these infections.

  5. Current status of schistosomiasis and soil-transmitted helminthiasis in Beyla and Macenta Prefectures, Forest Guinea.

    Science.gov (United States)

    Hodges, Mary; Koroma, Manso M; Baldé, Mamadou S; Turay, Hamid; Fofanah, Ibrahim; Divall, Mark J; Winkler, Mirko S; Zhang, Yaobi

    2011-11-01

    A cross-sectional survey was undertaken in children aged 9-14 years in Beyla and Macenta Prefectures, Forest Guinea. Stool samples were examined by Kato-Katz and urine samples were examined by the centrifugation method. The overall prevalence and intensity of infection was 66.2% and 462.4 eggs per gram of faeces (epg) for Schistosoma mansoni, 21.0% and 17.8 eggs per 10ml of urine for S. haematobium, 51.2% and 507.5 epg for hookworm, 8.1% and 89.1 epg for Ascaris lumbricoides and 2.4% and 16.7 epg for Trichuris trichiura. The overall prevalence of schistosomiasis (S. mansoni and/or S. haematobium) was 70.7%. The prevalence of schistosomiasis was similar to those reported in the 1990s in the region; however, the prevalence of soil-transmitted helminths has since fallen. These findings illustrate the need for schistosomiasis control in Guinea. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  6. Quadrature transmit coil for breast imaging at 7 tesla using forced current excitation for improved homogeneity.

    Science.gov (United States)

    McDougall, Mary Preston; Cheshkov, Sergey; Rispoli, Joseph; Malloy, Craig; Dimitrov, Ivan; Wright, Steven M

    2014-11-01

    To demonstrate the use of forced current excitation (FCE) to create homogeneous excitation of the breast at 7 tesla, insensitive to the effects of asymmetries in the electrical environment. FCE was implemented on two breast coils: one for quadrature (1) H imaging and one for proton-decoupled (13) C spectroscopy. Both were a Helmholtz-saddle combination, with the saddle tuned to 298 MHz for imaging and 75 MHz for spectroscopy. Bench measurements were acquired to demonstrate the ability to force equal currents on elements in the presence of asymmetric loading to improve homogeneity. Modeling and temperature measurements were conducted per safety protocol. B1 mapping, imaging, and proton-decoupled (13) C spectroscopy were demonstrated in vivo. Using FCE to ensure balanced currents on elements enabled straightforward tuning and maintaining of isolation between quadrature elements of the coil. Modeling and bench measurements confirmed homogeneity of the field, which resulted in images with excellent fat suppression and in broadband proton-decoupled carbon-13 spectra. FCE is a straightforward approach to ensure equal currents on multiple coil elements and a homogeneous excitation field, insensitive to the effects of asymmetries in the electrical environment. This enabled effective breast imaging and proton-decoupled carbon-13 spectroscopy at 7T. © 2014 Wiley Periodicals, Inc.

  7. Weakest solar wind of the space age and the current 'MINI' solar maximum

    International Nuclear Information System (INIS)

    McComas, D. J.; Angold, N.; Elliott, H. A.; Livadiotis, G.; Schwadron, N. A.; Smith, C. W.; Skoug, R. M.

    2013-01-01

    The last solar minimum, which extended into 2009, was especially deep and prolonged. Since then, sunspot activity has gone through a very small peak while the heliospheric current sheet achieved large tilt angles similar to prior solar maxima. The solar wind fluid properties and interplanetary magnetic field (IMF) have declined through the prolonged solar minimum and continued to be low through the current mini solar maximum. Compared to values typically observed from the mid-1970s through the mid-1990s, the following proton parameters are lower on average from 2009 through day 79 of 2013: solar wind speed and beta (∼11%), temperature (∼40%), thermal pressure (∼55%), mass flux (∼34%), momentum flux or dynamic pressure (∼41%), energy flux (∼48%), IMF magnitude (∼31%), and radial component of the IMF (∼38%). These results have important implications for the solar wind's interaction with planetary magnetospheres and the heliosphere's interaction with the local interstellar medium, with the proton dynamic pressure remaining near the lowest values observed in the space age: ∼1.4 nPa, compared to ∼2.4 nPa typically observed from the mid-1970s through the mid-1990s. The combination of lower magnetic flux emergence from the Sun (carried out in the solar wind as the IMF) and associated low power in the solar wind points to the causal relationship between them. Our results indicate that the low solar wind output is driven by an internal trend in the Sun that is longer than the ∼11 yr solar cycle, and they suggest that this current weak solar maximum is driven by the same trend.

  8. THE RISE AND FALL OF OPEN SOLAR FLUX DURING THE CURRENT GRAND SOLAR MAXIMUM

    International Nuclear Information System (INIS)

    Lockwood, M.; Rouillard, A. P.; Finch, I. D.

    2009-01-01

    We use geomagnetic activity data to study the rise and fall over the past century of the solar wind flow speed V SW , the interplanetary magnetic field strength B, and the open solar flux F S . Our estimates include allowance for the kinematic effect of longitudinal structure in the solar wind flow speed. As well as solar cycle variations, all three parameters show a long-term rise during the first half of the 20th century followed by peaks around 1955 and 1986 and then a recent decline. Cosmogenic isotope data reveal that this constitutes a grand maximum of solar activity which began in 1920, using the definition that such grand maxima are when 25-year averages of the heliospheric modulation potential exceeds 600 MV. Extrapolating the linear declines seen in all three parameters since 1985, yields predictions that the grand maximum will end in the years 2013, 2014, or 2027 using V SW , F S , or B, respectively. These estimates are consistent with predictions based on the probability distribution of the durations of past grand solar maxima seen in cosmogenic isotope data. The data contradict any suggestions of a floor to the open solar flux: we show that the solar minimum open solar flux, kinematically corrected to allow for the excess flux effect, has halved over the past two solar cycles.

  9. Testing Solutions of the Protection Systems Provided with Delay Maximum Current Relays

    Directory of Open Access Journals (Sweden)

    Horia BALAN

    2017-12-01

    Full Text Available Relay protection is one of the main forms of automation control of electro energy systems, having as primary aims fault detection and disconnection of the faulty element in order to avoid the extent of damages and the as fast as possible recovery to the normal operation regime for the rest of the system. Faults that occur in the electro energy system can be classified considering on one hand their causes and on the other their types, but in the vast majority of cases the causes of the faults are combined. Further, considering their nature, faults are classified in faults due to the insulation’s damage, in faults due to the destruction of the integrity of the circuits and faults determined by interruptions. With respect to their nature, faults are short circuits, earthing faults and phases interruptions. At the same time, considering their type, faults are divided in transversal and longitudinal ones. The paper presents a testing solution of the delayed maximal current relays using a T3000 ISA Test measuring equipment.

  10. On-coil multiple channel transmit system based on class-D amplification and pre-amplification with current amplitude feedback.

    Science.gov (United States)

    Gudino, Natalia; Heilman, Jeremiah A; Riffe, Matthew J; Heid, Oliver; Vester, Markus; Griswold, Mark A

    2013-07-01

    A complete high-efficiency transmit amplifier unit designed to be implemented in on-coil transmit arrays is presented. High power capability, low power dissipation, scalability, and cost minimization were some of the requirements imposed to the design. The system is composed of a current mode class-D amplifier output stage and a voltage mode class-D preamplification stage. The amplitude information of the radio frequency pulse was added through a customized step-down DC-DC converter with current amplitude feedback that connects to the current mode class-D stage. Benchtop measurements and imaging experiments were carried out to analyze system performance. Direct control of B1 was possible and its load sensitivity was reduced to less than 10% variation from unloaded to full loaded condition. When using the amplifiers in an array configuration, isolation above 20 dB was achieved between neighboring coils by the amplifier decoupling method. High output current operation of the transmitter was proved on the benchtop through output power measurements and in a 1.5T scanner through flip angle quantification. Finally, single and multiple channel excitations with the new hardware were demonstrated by receiving signal with the body coil of the scanner. Copyright © 2012 Wiley Periodicals, Inc.

  11. A targetted intervention research on traditional healer perspectives of sexually transmitted illnesses in urban Zambia. Current research.

    Science.gov (United States)

    Masauso Nzima, M; Romano, K; Anyangwe, S; Wiseman, J; Macwan'gi, M; Kendall, C; Green, E C

    1996-07-01

    Interviews with 81 traditional healers from 4 Copperbelt towns in Zambia (Chililabombwe, Chingola, Luanshya, and Mufulira) investigated healers' understanding of, attitudes toward, and management of sexually transmitted diseases (STDs). In general, Zambian traditional healers had detailed constructs of the physiology and infective processes underlying syphilis, gonorrhea, chancroid, and AIDS. STDs were considered to be caused by "dirt" or contamination residing in sperm or vaginal fluids and were closely linked to violations of moral codes. Healers shared complex nosologies based on distinctions between symptoms of different STD pathologies that were more inclusive than biomedical categories. Although condom use was not promoted, healers understood the importance of preventing an infective agent from passing from one person to another. Except for AIDS, STDs were considered curable by expelling the dirt through purgatives or emetics. Modern medicine was perceived as treating only STD symptoms, not curing. Most traditional healers insisted that the infected partner bring the other partner for consultation or treatment was withheld. Since these findings identified some areas of compatibility between indigenous and biomedical models of STDs, the Traditional Medicine Unit of the Ministry of Health and the HIV/AIDS Prevention Project of the Morehouse School of Medicine (Lusaka) established a program in which traditional healers receive AIDS training and learn to counsel clients on safer sex behaviors. Follow-up entails monthly meetings between health professionals and traditional healers. Since program initiation in June 1994, 800 traditional healers and 70 health professionals have participated. Traditional healers now sell condoms to their clients through a social marketing program.

  12. The Impacts of Maximum Temperature and Climate Change to Current and Future Pollen Distribution in Skopje, Republic of Macedonia

    Directory of Open Access Journals (Sweden)

    Vladimir Kendrovski

    2012-02-01

    Full Text Available BACKGROUND. The goal of the present paper was to assess the impact of current and future burden of the ambient temperature to pollen distributions in Skopje. METHODS. In the study we have evaluated a correlation between the concentration of pollen grains in the atmosphere of Skopje and maximum temperature, during the vegetation period of 1996, 2003, 2007 and 2009 as a current burden in context of climate change. For our analysis we have selected 9 representative of each phytoallergen group (trees, grasses, weeds. The concentration of pollen grains has been monitored by a Lanzoni volumetric pollen trap. The correlation between the concentration of pollen grains in the atmosphere and selected meteorological variable from weekly monitoring has been studied with the help of linear regression and correlation coefficients. RESULTS. The prevalence of the sensibilization of standard pollen allergens in Skopje during the some period shows increasing from 16,9% in 1996 to 19,8% in 2009. We detect differences in onset of flowering, maximum and end of the length of seasons for pollen. The pollen distributions and risk increases in 3 main periods: early spring, spring and summer which are the main cause of allergies during these seasons. The largest increase of air temperature due to climate change in Skopje is expected in the summer season. CONCLUSION. The impacts of climate change by increasing of the temperature in the next decades very likely will include impacts on pollen production and differences in current pollen season. [TAF Prev Med Bull 2012; 11(1.000: 35-40

  13. A Method of Maximum Power Control in Single-phase Utility Interactive Photovoltaic Generation System by using PWM Current Source Inverter

    Science.gov (United States)

    Neba, Yasuhiko

    This paper deals with a maximum power point tracking (MPPT) control of the photovoltaic generation with the single-phase utility interactive inverter. The photovoltaic arrays are connected by employing the PWM current source inverter to the utility. The use of the pulsating dc current and voltage allows the maximum power point to be searched. The inverter can regulate the array voltage and keep the arrays to the maximum power. This paper gives the control method and the experimental results.

  14. Optimisation of sea surface current retrieval using a maximum cross correlation technique on modelled sea surface temperature

    Science.gov (United States)

    Heuzé, Céline; Eriksson, Leif; Carvajal, Gisela

    2017-04-01

    Using sea surface temperature from satellite images to retrieve sea surface currents is not a new idea, but so far its operational near-real time implementation has not been possible. Validation studies are too region-specific or uncertain, due to the errors induced by the images themselves. Moreover, the sensitivity of the most common retrieval method, the maximum cross correlation, to the three parameters that have to be set is unknown. Using model outputs instead of satellite images, biases induced by this method are assessed here, for four different seas of Western Europe, and the best of nine settings and eight temporal resolutions are determined. For all regions, tracking a small 5 km pattern from the first image over a large 30 km region around its original location on a second image, separated from the first image by 6 to 9 hours returned the most accurate results. Moreover, for all regions, the problem is not inaccurate results but missing results, where the velocity is too low to be picked by the retrieval. The results are consistent both with limitations caused by ocean surface current dynamics and with the available satellite technology, indicating that automated sea surface current retrieval from sea surface temperature images is feasible now, for search and rescue operations, pollution confinement or even for more energy efficient and comfortable ship navigation.

  15. Predicting the current and future potential distributions of lymphatic filariasis in Africa using maximum entropy ecological niche modelling.

    Directory of Open Access Journals (Sweden)

    Hannah Slater

    Full Text Available Modelling the spatial distributions of human parasite species is crucial to understanding the environmental determinants of infection as well as for guiding the planning of control programmes. Here, we use ecological niche modelling to map the current potential distribution of the macroparasitic disease, lymphatic filariasis (LF, in Africa, and to estimate how future changes in climate and population could affect its spread and burden across the continent. We used 508 community-specific infection presence data collated from the published literature in conjunction with five predictive environmental/climatic and demographic variables, and a maximum entropy niche modelling method to construct the first ecological niche maps describing potential distribution and burden of LF in Africa. We also ran the best-fit model against climate projections made by the HADCM3 and CCCMA models for 2050 under A2a and B2a scenarios to simulate the likely distribution of LF under future climate and population changes. We predict a broad geographic distribution of LF in Africa extending from the west to the east across the middle region of the continent, with high probabilities of occurrence in the Western Africa compared to large areas of medium probability interspersed with smaller areas of high probability in Central and Eastern Africa and in Madagascar. We uncovered complex relationships between predictor ecological niche variables and the probability of LF occurrence. We show for the first time that predicted climate change and population growth will expand both the range and risk of LF infection (and ultimately disease in an endemic region. We estimate that populations at risk to LF may range from 543 and 804 million currently, and that this could rise to between 1.65 to 1.86 billion in the future depending on the climate scenario used and thresholds applied to signify infection presence.

  16. A Novel Technique for Maximum Power Point Tracking of a Photovoltaic Based on Sensing of Array Current Using Adaptive Neuro-Fuzzy Inference System (ANFIS)

    Science.gov (United States)

    El-Zoghby, Helmy M.; Bendary, Ahmed F.

    2016-10-01

    Maximum Power Point Tracking (MPPT) is now widely used method in increasing the photovoltaic (PV) efficiency. The conventional MPPT methods have many problems concerning the accuracy, flexibility and efficiency. The MPP depends on the PV temperature and solar irradiation that randomly varied. In this paper an artificial intelligence based controller is presented through implementing of an Adaptive Neuro-Fuzzy Inference System (ANFIS) to obtain maximum power from PV. The ANFIS inputs are the temperature and cell current, and the output is optimal voltage at maximum power. During operation the trained ANFIS senses the PV current using suitable sensor and also senses the temperature to determine the optimal operating voltage that corresponds to the current at MPP. This voltage is used to control the boost converter duty cycle. The MATLAB simulation results shows the effectiveness of the ANFIS with sensing the PV current in obtaining the MPPT from the PV.

  17. Current status of soil transmitted helminths and Schistosoma mansoni infection among children in two primary schools in North Gondar, Northwest Ethiopia: a cross sectional study.

    Science.gov (United States)

    Mathewos, Biniam; Alemu, Abebe; Woldeyohannes, Desalegn; Alemu, Agersew; Addis, Zelalem; Tiruneh, Moges; Aimero, Mulugeta; Kassu, Afework

    2014-02-10

    School age children are one of the groups at high risk for intestinal parasitic infections especially in developing countries like Ethiopia as the supply of good quality drinking water and latrine coverage are poor. Though there are previous data on the prevalence of soil transmitted helminths (STHs) and Schistosoma mansoni infection among these high risk groups current status in the study area is unknown. Therefore, the aim of this study was to determine the current prevalence and associated risk factors of STHs and S. mansoni infections among school children. A cross-sectional study was carried out in Gorgora and Chuahit towns, North Gondar Zone, North West Ethiopia from January 20 to February 25, 2012 involving 261 school children. A pre-tested and structured questionnaire was used to collect socio-demographic data and possible risk factors. Stool samples were collected and examined for intestinal parasites using Kato Katz method. Chi-square test was used to see if there is association between sociodemographic factors and other risk factors for STH and S. mansoni infection and odds ratio with 95% CI was computed as measures of association. P intestinal parasites. Ascaris lumbricoides was the predominant isolates (39.8%) followed by Trichuris trichiura (6.1%) and Hookworms (4.9%). Schistosoma mansoni was detected in 33.7% of the children. Among infected individuals, 9.5% were coinfected by S. mansoni and A. lumbricoides and 1.5% with S. mansoni and T. trichiura. Swimming habit (OR: 2.536, 95% CI: 1.122, 5.737, P = 0.022) was significantly associated with S. mansoni infection. The prevalence of STH and S. mansoni was high among school children. This should call for implementation of an integrated strategy to reduce morbidity and control of transmission of STH and S. mansoni.

  18. Current glaciation of the Chikhachev ridge (South-Eastern Altai and its dynamics after maximum of the Little Ice Age

    Directory of Open Access Journals (Sweden)

    D. A. Ganyushkin

    2016-01-01

    Full Text Available Glaciation of the Chikhachev ridge (South-Eastern Altai remains poorly known: field observations were not performed since the mid-twentieth century, available schemes and estimates of the glaciation and its scale made on the basis of remote sensing cover only a part of the glaciers, reconstructions of the Little Ice Age (LIA glaciations are absent. This research was based on interpretation of the satellite images: Landsat-4 (1989, Landsat-7 (2001, and Spot-5 (2011, as well as with the use of data of the field season of 2015. Characteristics of glaciations of the Chikhachev ridge as the whole and of its individual centers (Talduair massif, Mongun-Taiga-Minor massif, and southern part of the Chikhachev ridge were determined for the first time. Recent glaciation is represented by 7 glaciers with their total area of 1.12 km2 in the Talduair massif, by 5 glaciers with total area of 0.75 km2 in the Mongun-Taiga-Minor massif, and by 85 glaciers with total area of 29 km2 in the southern part of the Chikhachev ridge. Since the LIA maximum, areas of glaciers decreased by 61% in the Talduair massif, by 74% in the Mongun-Taiga-Minor massif, by 56% in the southern part of the Chikhachev ridge with simultaneous lifting of the firn line by 50 m, 65 m, and 70 m, respectively.The largest rates of the glacier contractions were determined for the period 1989–2011. Different mechanisms of the glacier retreats were shown by the example of the glacier complexes Burgastyn-Gol (one-sided retreat and disintegration and the Grigorjev glacier (gradual retreat of the tongue. Retreat of the Grigorjev glacier has been reconstructed for the period from the LIA maximum until 2015. Average rate of the retreat increased from 1,6 m/year in 1957–1989 up to 11,3 m/year in 2011–2015. The present-day scales of the glaciers and rates of their retreating do not significantly differ from estimations made by other researchers for the nearest centers of glaciation of the

  19. A Comparative Frequency Analysis of Maximum Daily Rainfall for a SE Asian Region under Current and Future Climate Conditions

    Directory of Open Access Journals (Sweden)

    Velautham Daksiya

    2017-01-01

    Full Text Available The impact of changing climate on the frequency of daily rainfall extremes in Jakarta, Indonesia, is analysed and quantified. The study used three different models to assess the changes in rainfall characteristics. The first method involves the use of the weather generator LARS-WG to quantify changes between historical and future daily rainfall maxima. The second approach consists of statistically downscaling general circulation model (GCM output based on historical empirical relationships between GCM output and station rainfall. Lastly, the study employed recent statistically downscaled global gridded rainfall projections to characterize climate change impact rainfall structure. Both annual and seasonal rainfall extremes are studied. The results show significant changes in annual maximum daily rainfall, with an average increase as high as 20% in the 100-year return period daily rainfall. The uncertainty arising from the use of different GCMs was found to be much larger than the uncertainty from the emission scenarios. Furthermore, the annual and wet seasonal analyses exhibit similar behaviors with increased future rainfall, but the dry season is not consistent across the models. The GCM uncertainty is larger in the dry season compared to annual and wet season.

  20. Current status of human rabies transmitted by dogs in Latin America Raiva humana transmitida por caninos: situação atual na América Latina

    Directory of Open Access Journals (Sweden)

    Maria Cristina Schneider

    2007-09-01

    Full Text Available Latin American countries made the political decision to eliminate human rabies transmitted by dogs by the year 2005. The purpose of the current study is to evaluate to what extent this goal has been reached. The epidemiological situation and control measures were analyzed and broken down within the countries by georeferencing. The 27 human cases reported in 2003 occurred in some 0.2% of the second-level geopolitical units (municipalities or counties in the region, suggesting that the disease is a local problem. Several areas within the countries reported no more transmission of rabies in dogs. Nearly 1 million people potentially exposed to rabies received treatment. On average, 34,383 inhabitants per health post receive anti-rabies treatment (range: 4,300-148,043. Nearly 42 million dogs are vaccinated annually. Surveillance is considered fair according to the epidemiological criteria adopted by the study. Samples sent for rabies testing represent 0.05% of the estimated canine population (range: 0.001 to 0.2%. The countries are quite close to achieving the goal.Os países da América Latina tomaram a decisão política de eliminar a raiva humana transmitida por cão até 2005, e o objetivo deste estudo é analisar o cumprimento desta meta. A situação epidemiológica e as ações de controle foram analisadas de forma desagregada dentro dos países, utilizando-se georreferenciamento da informação. Os 27 casos humanos relatados em 2003 ocorreram em cerca de 0,2% das unidades de segundo nível geopolítico (municípios da região. Esse dado sugere que a doença atualmente é muito localizada. Vários países não reportam mais transmissão de raiva em cães. Cerca de 1 milhão de pessoas são potencialmente expostas ao risco da raiva e recebem atendimento médico. Existem em média 34.383 (classe: 4.300-148.043 habitantes por posto de saúde com tratamento anti-rábico. São vacinados cerca de 42 milhões de cães anualmente, 70% deles no Brasil

  1. SEXUALLY TRANSMITTED DISEASES - HISTORY, TYPES, PREVALENCE, EPIDEMIOLOGY

    Directory of Open Access Journals (Sweden)

    Valentin Irmov

    2017-12-01

    Full Text Available Sexually transmitted infections affect persons of active sex and cause serious consequences for the human organism, society and the generation. They spread sporadically, epidemically, and in some of them there are pandemics. For example, humanity is currently in a third viral hepatitis pandemic and a first AIDS pandemic. Another group of diseases can also be transmitted through sexual contact, but this is not the main mode of transmission. Such are salmonellosis, amoebiasis, influenza, various causes of meningitis and pneumonia. Despite being sexually transmitted, this is not a major and almost irrelevant way of transmitting the infection. Therefore, the diseases themselves are not included in the group of sexually transmitted diseases.

  2. Comparing modeled and observed changes in mineral dust transport and deposition to Antarctica between the Last Glacial Maximum and current climates

    Energy Technology Data Exchange (ETDEWEB)

    Albani, Samuel [University of Siena, Graduate School in Polar Sciences, Siena (Italy); University of Milano-Bicocca, Department of Environmental Sciences, Milano (Italy); Cornell University, Department of Earth and Atmospheric Sciences, Ithaca, NY (United States); Mahowald, Natalie M. [Cornell University, Department of Earth and Atmospheric Sciences, Ithaca, NY (United States); Delmonte, Barbara; Maggi, Valter [University of Milano-Bicocca, Department of Environmental Sciences, Milano (Italy); Winckler, Gisela [Columbia University, Lamont-Doherty Earth Observatory, Palisades, NY (United States); Columbia University, Department of Earth and Environmental Sciences, New York, NY (United States)

    2012-05-15

    Mineral dust aerosols represent an active component of the Earth's climate system, by interacting with radiation directly, and by modifying clouds and biogeochemistry. Mineral dust from polar ice cores over the last million years can be used as paleoclimate proxy, and provide unique information about climate variability, as changes in dust deposition at the core sites can be due to changes in sources, transport and/or deposition locally. Here we present results from a study based on climate model simulations using the Community Climate System Model. The focus of this work is to analyze simulated differences in the dust concentration, size distribution and sources in current climate conditions and during the Last Glacial Maximum at specific ice core locations in Antarctica, and compare with available paleodata. Model results suggest that South America is the most important source for dust deposited in Antarctica in current climate, but Australia is also a major contributor and there is spatial variability in the relative importance of the major dust sources. During the Last Glacial Maximum the dominant source in the model was South America, because of the increased activity of glaciogenic dust sources in Southern Patagonia-Tierra del Fuego and the Southernmost Pampas regions, as well as an increase in transport efficiency southward. Dust emitted from the Southern Hemisphere dust source areas usually follow zonal patterns, but southward flow towards Antarctica is located in specific areas characterized by southward displacement of air masses. Observations and model results consistently suggest a spatially variable shift in dust particle sizes. This is due to a combination of relatively reduced en route wet removal favouring a generalized shift towards smaller particles, and on the other hand to an enhanced relative contribution of dry coarse particle deposition in the Last Glacial Maximum. (orig.)

  3. Radio Frequency Transistors Using Aligned Semiconducting Carbon Nanotubes with Current-Gain Cutoff Frequency and Maximum Oscillation Frequency Simultaneously Greater than 70 GHz.

    Science.gov (United States)

    Cao, Yu; Brady, Gerald J; Gui, Hui; Rutherglen, Chris; Arnold, Michael S; Zhou, Chongwu

    2016-07-26

    In this paper, we report record radio frequency (RF) performance of carbon nanotube transistors based on combined use of a self-aligned T-shape gate structure, and well-aligned, high-semiconducting-purity, high-density polyfluorene-sorted semiconducting carbon nanotubes, which were deposited using dose-controlled, floating evaporative self-assembly method. These transistors show outstanding direct current (DC) performance with on-current density of 350 μA/μm, transconductance as high as 310 μS/μm, and superior current saturation with normalized output resistance greater than 100 kΩ·μm. These transistors create a record as carbon nanotube RF transistors that demonstrate both the current-gain cutoff frequency (ft) and the maximum oscillation frequency (fmax) greater than 70 GHz. Furthermore, these transistors exhibit good linearity performance with 1 dB gain compression point (P1dB) of 14 dBm and input third-order intercept point (IIP3) of 22 dBm. Our study advances state-of-the-art of carbon nanotube RF electronics, which have the potential to be made flexible and may find broad applications for signal amplification, wireless communication, and wearable/flexible electronics.

  4. Modification of the deep salinity-maximum in the Southern Ocean by circulation in the Antarctic Circumpolar Current and the Weddell Gyre

    Science.gov (United States)

    Donnelly, Matthew; Leach, Harry; Strass, Volker

    2017-07-01

    The evolution of the deep salinity-maximum associated with the Lower Circumpolar Deep Water (LCDW) is assessed using a set of 37 hydrographic sections collected over a 20-year period in the Southern Ocean as part of the WOCE/CLIVAR programme. A circumpolar decrease in the value of the salinity-maximum is observed eastwards from the North Atlantic Deep Water (NADW) in the Atlantic sector of the Southern Ocean through the Indian and Pacific sectors to Drake Passage. Isopycnal mixing processes are limited by circumpolar fronts, and in the Atlantic sector, this acts to limit the direct poleward propagation of the salinity signal. Limited entrainment occurs into the Weddell Gyre, with LCDW entering primarily through the eddy-dominated eastern limb. A vertical mixing coefficient, κV of (2.86 ± 1.06) × 10-4 m2 s-1 and an isopycnal mixing coefficient, κI of (8.97 ± 1.67) × 102 m2 s-1 are calculated for the eastern Indian and Pacific sectors of the Antarctic Circumpolar Current (ACC). A κV of (2.39 ± 2.83) × 10-5 m2 s-1, an order of magnitude smaller, and a κI of (2.47 ± 0.63) × 102 m2 s-1, three times smaller, are calculated for the southern and eastern Weddell Gyre reflecting a more turbulent regime in the ACC and a less turbulent regime in the Weddell Gyre. In agreement with other studies, we conclude that the ACC acts as a barrier to direct meridional transport and mixing in the Atlantic sector evidenced by the eastward propagation of the deep salinity-maximum signal, insulating the Weddell Gyre from short-term changes in NADW characteristics.

  5. Last Glacial Maximum to Holocene climate evolution controlled by sea-level change, Leeuwin Current, and Australian Monsoon in the Northwestern Australia

    Science.gov (United States)

    Ishiwa, T.; Yokoyama, Y.; McHugh, C.; Reuning, L.; Gallagher, S. J.

    2017-12-01

    The transition from cold to warm conditions during the last deglaciation influenced climate variability in the Indian Ocean and Pacific as a result of submerge of continental shelf and variations in the Indonesian Throughflow and Australian Monsoon. The shallow continental shelf (Program Expedition 356 Indonesian Throughflow drilled in the northwestern Australian shallow continental shelf and recovered an interval from the Last Glacial Maximum to Holocene in Site U1461. Radiocarbon dating on macrofossils, foraminifera, and bulk organic matter provided a precise age-depth model, leading to high-resolved paleoclimate reconstruction. X-ray elemental analysis results are interpreted as an indicator of sedimentary environmental changes. The upper 20-m part of Site U1461 apparently records the climate transition from the LGM to Holocene in the northwestern Australia, which could be associated with sea-level change, Leeuwin Current activity, and the Australian Monsoon.

  6. Current socioclinical trend of sexually transmitted diseases and relevance of STD clinic: A comparative study from referral tertiary care center of Gwalior, India

    Directory of Open Access Journals (Sweden)

    Sandeep Singh

    2014-01-01

    Full Text Available Objective: Sexually transmitted infections (STIs are the major public health concern in both developed and developing countries regulated by the cultural pattern of gender expression in their society. Thus, it demanded a necessary action to review the changing pattern in (Gwalior, central India where health condition is not in a good fashion with poor socioeconomic status and awareness. Materials and Methods: This is a hospital based cross sectional questionnaire study with a sample size of 222 respondents attending sexually transmitted disease (STD clinic at JAH Gwalior from December 2011 to March 2012 using a random sampling method. Results: Most of the cases among females were in the age group of 20-40 years (152, 84.44% and males were in 18-40 years age group (35, 83.33%. Out of 180, 22 (12.22% females were having non-regular sexual partners. Out of 22 females frequency of consistent, non-consistent, and no condom use with non-regular sexual partners was three (13.63%, two (9.09%, and 17 (77.27%, respectively. Out of 42 males, 22 (52.38% reported having sex with non-regular sexual partners. None of the 15 (100% male subjects having friends or relatives as non-regular sexual partner were using condoms. Statistically significant differences were found as compared to a previous study from same STD clinic are discharge, lower abdominal pain, painful micturition, nodules in genitals as 106 (58.88%; P = 0.0001, 59 (32.77%; P = 0.0007, 25 (13.88%; P = 0.001, and one (0.5%; P = 0.005, respectively and in males with absence of abdominal pain and nodules in genitals as P = 0.016 and 0.03, respectively. Preferred place of treatment of STIs was government facility in both male and females with statistically significant 15.76% (P = 0.0001 of the population seeking no treatment. Discussions: Study suggests a changing trend of the STDs owing to the difference in the clinical presentation of the disease to a previous study from the same STD clinic few years

  7. Sexually transmitted diphtheria.

    Science.gov (United States)

    Berger, Anja; Lensing, Carmen; Konrad, Regina; Huber, Ingrid; Hogardt, Michael; Sing, Andreas

    2013-03-01

    Diphtheria is caused by diphtheria toxin-producing Corynebacterium species. While classical respiratory diphtheria is transmitted by droplets, cutaneous diphtheria often results from minor trauma. This report concerns the first case of sexually transmitted diphtheria in a patient with non-gonococcal urethritis after orogenital contact.

  8. Sexually transmitted infections

    African Journals Online (AJOL)

    AJRH Managing Editor

    Sexually transmitted infections constitute economic burden for developing countries, exposure to causative agents is an occupational hazard ... In Nigeria, the deteriorating economic situation has led to ..... female sex workers from Mexico City.

  9. Maximum power demand cost

    International Nuclear Information System (INIS)

    Biondi, L.

    1998-01-01

    The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

  10. Integrated Reconfigurable High-Voltage Transmitting Circuit for CMUTs

    DEFF Research Database (Denmark)

    Llimos Muntal, Pere; Larsen, Dennis Øland; Jørgensen, Ivan Harald Holger

    2014-01-01

    -out and measurements are performed on the integrated circuit. The transmitting circuit is reconfigurable externally making it able to drive a wide variety of CMUTs. The transmitting circuit can generate several pulse shapes, pulse voltages up to 100 V, maximum pulse range of 50 V and frequencies up to 5 MHz. The area...

  11. Maximum-Likelihood Detection Of Noncoherent CPM

    Science.gov (United States)

    Divsalar, Dariush; Simon, Marvin K.

    1993-01-01

    Simplified detectors proposed for use in maximum-likelihood-sequence detection of symbols in alphabet of size M transmitted by uncoded, full-response continuous phase modulation over radio channel with additive white Gaussian noise. Structures of receivers derived from particular interpretation of maximum-likelihood metrics. Receivers include front ends, structures of which depends only on M, analogous to those in receivers of coherent CPM. Parts of receivers following front ends have structures, complexity of which would depend on N.

  12. Integrated reconfigurable high-voltage transmitting circuit for CMUTs

    DEFF Research Database (Denmark)

    Llimos Muntal, Pere; Larsen, Dennis Øland; Jørgensen, Ivan Harald Holger

    2015-01-01

    In this paper a high-voltage transmitting circuit aimed for capacitive micromachined ultrasonic transducers (CMUTs) used in scanners for medical applications is designed and implemented in a 0.35 μm high-voltage CMOS process. The transmitting circuit is reconfigurable externally making it able...... to drive a wide variety of CMUTs. The transmitting circuit can generate several pulse shapes with voltages up to 100 V, maximum pulse range of 50 V, frequencies up to 5 MHz and different driving slew rates. Measurements are performed on the circuit in order to assess its functionality and power consumption...... performance. The design occupies an on-chip area of 0.938 mm2 and the power consumption of a 128-element transmitting circuit array that would be used in an portable ultrasound scanner is found to be a maximum of 181 mW....

  13. Maximum power point tracking

    International Nuclear Information System (INIS)

    Enslin, J.H.R.

    1990-01-01

    A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

  14. 2012 Sexually Transmitted Diseases Surveillance, Other Sexually Transmitted Diseases

    Science.gov (United States)

    ... 2012 Sexually Transmitted Diseases Surveillance Table of Contents Introductory Section Foreword Preface Acronyms Figures- National Profile Figures - ... GISP Profiles Related Links STD Home STD Data & Statistics NCHHSTP Atlas Interactive STD Data - 1996-2013 STD ...

  15. [Dutch Institute for Health Care Improvement revised guideline, 'Sexually transmitted diseases and neonatal herpes'

    NARCIS (Netherlands)

    Bleker, O.P.; Meijden, W.I. van der; Wittenberg, J.; Bergen, J.E. van; Boeke, A.J.; Doornum, G.J.J. van; Henquet, C.J.; Galama, J.M.D.; Postma, M.J.; Prins, J.M.; Voorst Vader, P.C. van

    2003-01-01

    The Dutch Institute for Health Care Improvement revised guideline, 'Sexually transmitted diseases and neonatal herpes' summarises the current scientific position on the diagnosis and treatment of a great number of sexually transmitted diseases (STD) and neonatal herpes. Symptomatic treatment of

  16. Probable maximum flood control

    International Nuclear Information System (INIS)

    DeGabriele, C.E.; Wu, C.L.

    1991-11-01

    This study proposes preliminary design concepts to protect the waste-handling facilities and all shaft and ramp entries to the underground from the probable maximum flood (PMF) in the current design configuration for the proposed Nevada Nuclear Waste Storage Investigation (NNWSI) repository protection provisions were furnished by the United States Bureau of Reclamation (USSR) or developed from USSR data. Proposed flood protection provisions include site grading, drainage channels, and diversion dikes. Figures are provided to show these proposed flood protection provisions at each area investigated. These areas are the central surface facilities (including the waste-handling building and waste treatment building), tuff ramp portal, waste ramp portal, men-and-materials shaft, emplacement exhaust shaft, and exploratory shafts facility

  17. Soil-Transmitted Helminth Infections

    Science.gov (United States)

    ... Schistosomiasis and soil-transmitted helminth infections More about neglected tropical diseases News WHO recommends large-scale deworming to improve children’s health and nutrition 29 September 2017 About us ...

  18. Scintillation counter, maximum gamma aspect

    International Nuclear Information System (INIS)

    Thumim, A.D.

    1975-01-01

    A scintillation counter, particularly for counting gamma ray photons, includes a massive lead radiation shield surrounding a sample-receiving zone. The shield is disassembleable into a plurality of segments to allow facile installation and removal of a photomultiplier tube assembly, the segments being so constructed as to prevent straight-line access of external radiation through the shield into radiation-responsive areas. Provisions are made for accurately aligning the photomultiplier tube with respect to one or more sample-transmitting bores extending through the shield to the sample receiving zone. A sample elevator, used in transporting samples into the zone, is designed to provide a maximum gamma-receiving aspect to maximize the gamma detecting efficiency. (U.S.)

  19. Approximate maximum parsimony and ancestral maximum likelihood.

    Science.gov (United States)

    Alon, Noga; Chor, Benny; Pardi, Fabio; Rapoport, Anat

    2010-01-01

    We explore the maximum parsimony (MP) and ancestral maximum likelihood (AML) criteria in phylogenetic tree reconstruction. Both problems are NP-hard, so we seek approximate solutions. We formulate the two problems as Steiner tree problems under appropriate distances. The gist of our approach is the succinct characterization of Steiner trees for a small number of leaves for the two distances. This enables the use of known Steiner tree approximation algorithms. The approach leads to a 16/9 approximation ratio for AML and asymptotically to a 1.55 approximation ratio for MP.

  20. Modelling information flow along the human connectome using maximum flow.

    Science.gov (United States)

    Lyoo, Youngwook; Kim, Jieun E; Yoon, Sujung

    2018-01-01

    The human connectome is a complex network that transmits information between interlinked brain regions. Using graph theory, previously well-known network measures of integration between brain regions have been constructed under the key assumption that information flows strictly along the shortest paths possible between two nodes. However, it is now apparent that information does flow through non-shortest paths in many real-world networks such as cellular networks, social networks, and the internet. In the current hypothesis, we present a novel framework using the maximum flow to quantify information flow along all possible paths within the brain, so as to implement an analogy to network traffic. We hypothesize that the connection strengths of brain networks represent a limit on the amount of information that can flow through the connections per unit of time. This allows us to compute the maximum amount of information flow between two brain regions along all possible paths. Using this novel framework of maximum flow, previous network topological measures are expanded to account for information flow through non-shortest paths. The most important advantage of the current approach using maximum flow is that it can integrate the weighted connectivity data in a way that better reflects the real information flow of the brain network. The current framework and its concept regarding maximum flow provides insight on how network structure shapes information flow in contrast to graph theory, and suggests future applications such as investigating structural and functional connectomes at a neuronal level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Maximum permissible dose

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    This chapter presents a historic overview of the establishment of radiation guidelines by various national and international agencies. The use of maximum permissible dose and maximum permissible body burden limits to derive working standards is discussed

  2. Nosocomial Infections Transmitted Via Computers : A Literature Review

    OpenAIRE

    Atanda, Angela Achieng; Nwaoha, Nkechi Naomi

    2010-01-01

    The purpose of this review was to discuss how current literature described nosocomial infections transmitted via computers in hospitals. It also described the various methods used to disinfect computers. The research questions in this study were; What are nosocomial infections? How do contaminated computer devices transmit nosocomial infections? and What infection control methods are applied to decontaminate computers within hospitals? The aim of conducting this study was to create an aw...

  3. Maximum Acceleration Recording Circuit

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Coarsely digitized maximum levels recorded in blown fuses. Circuit feeds power to accelerometer and makes nonvolatile record of maximum level to which output of accelerometer rises during measurement interval. In comparison with inertia-type single-preset-trip-point mechanical maximum-acceleration-recording devices, circuit weighs less, occupies less space, and records accelerations within narrower bands of uncertainty. In comparison with prior electronic data-acquisition systems designed for same purpose, circuit simpler, less bulky, consumes less power, costs and analysis of data recorded in magnetic or electronic memory devices. Circuit used, for example, to record accelerations to which commodities subjected during transportation on trucks.

  4. Internationalism in sexually transmitted infections.

    Science.gov (United States)

    Waugh, M A

    1997-12-01

    The International Union Against the Venereal Diseases and the Treponematoses (IUVDT) became the International Union Against Sexually Transmitted Infections (IUSTI) at the Union's 37th General Assembly, held in Melbourne, Australia. The name change reflects the increasing use by international donor organizations of the term sexually transmitted infections (STIs). STIs are a major problem in Africa, South East Asia, India, Russia, and the European countries which were formerly within the Communist bloc. The epidemic of syphilis together with HIV increases daily in Eastern Europe and Russia. There have, however, been some successes in developing countries with the syndromic method, the promotion of sexual health, and the prevention of STIs. While the UK has the largest body of fully trained sexually transmitted disease (STD) specialists in the world, comparatively few of them participate in large international commitments. These specialists should instead become more involved with STIs in areas of need. Furthermore, more aid should be provided by governmental, nongovernmental, and charitable sources. IUSTI is willing to cooperate with any efforts to fight STDs anywhere in the world.

  5. Maximum Entropy in Drug Discovery

    Directory of Open Access Journals (Sweden)

    Chih-Yuan Tseng

    2014-07-01

    Full Text Available Drug discovery applies multidisciplinary approaches either experimentally, computationally or both ways to identify lead compounds to treat various diseases. While conventional approaches have yielded many US Food and Drug Administration (FDA-approved drugs, researchers continue investigating and designing better approaches to increase the success rate in the discovery process. In this article, we provide an overview of the current strategies and point out where and how the method of maximum entropy has been introduced in this area. The maximum entropy principle has its root in thermodynamics, yet since Jaynes’ pioneering work in the 1950s, the maximum entropy principle has not only been used as a physics law, but also as a reasoning tool that allows us to process information in hand with the least bias. Its applicability in various disciplines has been abundantly demonstrated. We give several examples of applications of maximum entropy in different stages of drug discovery. Finally, we discuss a promising new direction in drug discovery that is likely to hinge on the ways of utilizing maximum entropy.

  6. Maximum Quantum Entropy Method

    OpenAIRE

    Sim, Jae-Hoon; Han, Myung Joon

    2018-01-01

    Maximum entropy method for analytic continuation is extended by introducing quantum relative entropy. This new method is formulated in terms of matrix-valued functions and therefore invariant under arbitrary unitary transformation of input matrix. As a result, the continuation of off-diagonal elements becomes straightforward. Without introducing any further ambiguity, the Bayesian probabilistic interpretation is maintained just as in the conventional maximum entropy method. The applications o...

  7. Maximum Power from a Solar Panel

    Directory of Open Access Journals (Sweden)

    Michael Miller

    2010-01-01

    Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

  8. Maximum likely scale estimation

    DEFF Research Database (Denmark)

    Loog, Marco; Pedersen, Kim Steenstrup; Markussen, Bo

    2005-01-01

    A maximum likelihood local scale estimation principle is presented. An actual implementation of the estimation principle uses second order moments of multiple measurements at a fixed location in the image. These measurements consist of Gaussian derivatives possibly taken at several scales and/or ...

  9. Robust Maximum Association Estimators

    NARCIS (Netherlands)

    A. Alfons (Andreas); C. Croux (Christophe); P. Filzmoser (Peter)

    2017-01-01

    textabstractThe maximum association between two multivariate variables X and Y is defined as the maximal value that a bivariate association measure between one-dimensional projections αX and αY can attain. Taking the Pearson correlation as projection index results in the first canonical correlation

  10. Maximum a posteriori decoder for digital communications

    Science.gov (United States)

    Altes, Richard A. (Inventor)

    1997-01-01

    A system and method for decoding by identification of the most likely phase coded signal corresponding to received data. The present invention has particular application to communication with signals that experience spurious random phase perturbations. The generalized estimator-correlator uses a maximum a posteriori (MAP) estimator to generate phase estimates for correlation with incoming data samples and for correlation with mean phases indicative of unique hypothesized signals. The result is a MAP likelihood statistic for each hypothesized transmission, wherein the highest value statistic identifies the transmitted signal.

  11. Maximum permissible voltage of YBCO coated conductors

    Energy Technology Data Exchange (ETDEWEB)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z. [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Hong, Z., E-mail: zhiyong.hong@sjtu.edu.cn [Department of Electrical Engineering, Shanghai Jiao Tong University, Shanghai (China); Wang, D.; Zhou, H.; Shen, X.; Shen, C. [Qingpu Power Supply Company, State Grid Shanghai Municipal Electric Power Company, Shanghai (China)

    2014-06-15

    Highlights: • We examine three kinds of tapes’ maximum permissible voltage. • We examine the relationship between quenching duration and maximum permissible voltage. • Continuous I{sub c} degradations under repetitive quenching where tapes reaching maximum permissible voltage. • The relationship between maximum permissible voltage and resistance, temperature. - Abstract: Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (I{sub c}) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the I{sub c} degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  12. Modelling maximum canopy conductance and transpiration in ...

    African Journals Online (AJOL)

    There is much current interest in predicting the maximum amount of water that can be transpired by Eucalyptus trees. It is possible that industrial waste water may be applied as irrigation water to eucalypts and it is important to predict the maximum transpiration rates of these plantations in an attempt to dispose of this ...

  13. Maximum entropy methods

    International Nuclear Information System (INIS)

    Ponman, T.J.

    1984-01-01

    For some years now two different expressions have been in use for maximum entropy image restoration and there has been some controversy over which one is appropriate for a given problem. Here two further entropies are presented and it is argued that there is no single correct algorithm. The properties of the four different methods are compared using simple 1D simulations with a view to showing how they can be used together to gain as much information as possible about the original object. (orig.)

  14. The last glacial maximum

    Science.gov (United States)

    Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

    2009-01-01

    We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

  15. Current status of soil-transmitted helminths in Vietnam

    DEFF Research Database (Denmark)

    van der Hoek, Wim; De, Nguyen Van; Konradsen, Flemming

    2003-01-01

    is more evenly distributed throughout the country, but is concentrated in peri-urban and rural agricultural areas. Vegetable cultivation in which nightsoil is used as fertilizer is a risk factor for hookworm infection, especially among adult women. Helminth control programs should be targeted at school......-age children in the northern provinces. Specific interventions are needed throughout the country for women of agricultural communities that are at risk for hookworm infection. There is clearly a need for more detailed analysis of risk factors to quantify the relative contribution of climatic, environmental...

  16. Decreasing Prevalence of Transfusion Transmitted Infection in Indian Scenario

    Directory of Open Access Journals (Sweden)

    Tulika Chandra

    2014-01-01

    Full Text Available Transfusion transmitted infections are major problem associated with blood transfusion. Accurate estimates of risk of TTIs are essential for monitoring the safety of blood supply and evaluating the efficacy of currently employed screening procedures. The present study was carried out to assess the percentage of voluntary donors and replacement donors and to find out prevalence and changing trends of various TTIs blood donors in recent years. A study was carried out on blood units of voluntary and replacement donors which were collected from January 2008 to December 2012. On screening of 180,371 replacement units, seropositivity of transfusion transmitted disease in replacement donors was 0.15% in HIV, 1.67% in hepatitis B surface antigen, 0.49% in hepatitis C virus, 0.01% in VDRL, and 0.009% in malaria. Of 11,977 voluntary units, seropositivity of transfusion transmitted disease in voluntary donors was 0.08% in HIV, 0.24% in hepatitis B surface antigen, 0.001% in hepatitis C virus, 0.008% in VDRL (sexually transmitted disease, and 0.01% in malaria. From results it has been concluded that prevalence of transfusion transmitted infection (HIV, HBV, HCV, VDRL, and malaria was more in replacement donors in comparison to voluntary donors. Extensive donor selection and screening procedures will help in improving the blood safety.

  17. Maximum Entropy Fundamentals

    Directory of Open Access Journals (Sweden)

    F. Topsøe

    2001-09-01

    Full Text Available Abstract: In its modern formulation, the Maximum Entropy Principle was promoted by E.T. Jaynes, starting in the mid-fifties. The principle dictates that one should look for a distribution, consistent with available information, which maximizes the entropy. However, this principle focuses only on distributions and it appears advantageous to bring information theoretical thinking more prominently into play by also focusing on the "observer" and on coding. This view was brought forward by the second named author in the late seventies and is the view we will follow-up on here. It leads to the consideration of a certain game, the Code Length Game and, via standard game theoretical thinking, to a principle of Game Theoretical Equilibrium. This principle is more basic than the Maximum Entropy Principle in the sense that the search for one type of optimal strategies in the Code Length Game translates directly into the search for distributions with maximum entropy. In the present paper we offer a self-contained and comprehensive treatment of fundamentals of both principles mentioned, based on a study of the Code Length Game. Though new concepts and results are presented, the reading should be instructional and accessible to a rather wide audience, at least if certain mathematical details are left aside at a rst reading. The most frequently studied instance of entropy maximization pertains to the Mean Energy Model which involves a moment constraint related to a given function, here taken to represent "energy". This type of application is very well known from the literature with hundreds of applications pertaining to several different elds and will also here serve as important illustration of the theory. But our approach reaches further, especially regarding the study of continuity properties of the entropy function, and this leads to new results which allow a discussion of models with so-called entropy loss. These results have tempted us to speculate over

  18. Vaginal microbiota and viral sexually transmitted diseases.

    Science.gov (United States)

    Nardis, C; Mosca, L; Mastromarino, P

    2013-01-01

    Healthy vaginal microbiota is an important biological barrier to pathogenic microorganisms. When this predominantly Lactobacillus community is disrupted, decreased in abundance and replaced by different anaerobes, bacterial vaginosis (BV) may occur. BV is associated with prevalence and incidence of several sexually transmitted infections. This review provides background on BV, discusses the epidemiologic data to support a role of altered vaginal microbiota for acquisition of sexually transmitted diseases and analyzes mechanisms by which lactobacilli could counteract sexually transmitted viral infections.

  19. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1988-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. We review the need for such methods in data analysis and show, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. We conclude with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  20. Solar maximum observatory

    International Nuclear Information System (INIS)

    Rust, D.M.

    1984-01-01

    The successful retrieval and repair of the Solar Maximum Mission (SMM) satellite by Shuttle astronauts in April 1984 permitted continuance of solar flare observations that began in 1980. The SMM carries a soft X ray polychromator, gamma ray, UV and hard X ray imaging spectrometers, a coronagraph/polarimeter and particle counters. The data gathered thus far indicated that electrical potentials of 25 MeV develop in flares within 2 sec of onset. X ray data show that flares are composed of compressed magnetic loops that have come too close together. Other data have been taken on mass ejection, impacts of electron beams and conduction fronts with the chromosphere and changes in the solar radiant flux due to sunspots. 13 references

  1. Introduction to maximum entropy

    International Nuclear Information System (INIS)

    Sivia, D.S.

    1989-01-01

    The maximum entropy (MaxEnt) principle has been successfully used in image reconstruction in a wide variety of fields. The author reviews the need for such methods in data analysis and shows, by use of a very simple example, why MaxEnt is to be preferred over other regularizing functions. This leads to a more general interpretation of the MaxEnt method, and its use is illustrated with several different examples. Practical difficulties with non-linear problems still remain, this being highlighted by the notorious phase problem in crystallography. He concludes with an example from neutron scattering, using data from a filter difference spectrometer to contrast MaxEnt with a conventional deconvolution. 12 refs., 8 figs., 1 tab

  2. Functional Maximum Autocorrelation Factors

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Nielsen, Allan Aasbjerg

    2005-01-01

    MAF outperforms the functional PCA in concentrating the interesting' spectra/shape variation in one end of the eigenvalue spectrum and allows for easier interpretation of effects. Conclusions. Functional MAF analysis is a useful methods for extracting low dimensional models of temporally or spatially......Purpose. We aim at data where samples of an underlying function are observed in a spatial or temporal layout. Examples of underlying functions are reflectance spectra and biological shapes. We apply functional models based on smoothing splines and generalize the functional PCA in......\\verb+~+\\$\\backslash\\$cite{ramsay97} to functional maximum autocorrelation factors (MAF)\\verb+~+\\$\\backslash\\$cite{switzer85,larsen2001d}. We apply the method to biological shapes as well as reflectance spectra. {\\$\\backslash\\$bf Methods}. MAF seeks linear combination of the original variables that maximize autocorrelation between...

  3. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yunji; Jing, Bing-Yi; Gao, Xin

    2015-01-01

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  4. Regularized maximum correntropy machine

    KAUST Repository

    Wang, Jim Jing-Yan

    2015-02-12

    In this paper we investigate the usage of regularized correntropy framework for learning of classifiers from noisy labels. The class label predictors learned by minimizing transitional loss functions are sensitive to the noisy and outlying labels of training samples, because the transitional loss functions are equally applied to all the samples. To solve this problem, we propose to learn the class label predictors by maximizing the correntropy between the predicted labels and the true labels of the training samples, under the regularized Maximum Correntropy Criteria (MCC) framework. Moreover, we regularize the predictor parameter to control the complexity of the predictor. The learning problem is formulated by an objective function considering the parameter regularization and MCC simultaneously. By optimizing the objective function alternately, we develop a novel predictor learning algorithm. The experiments on two challenging pattern classification tasks show that it significantly outperforms the machines with transitional loss functions.

  5. Maximum entropy tokamak configurations

    International Nuclear Information System (INIS)

    Minardi, E.

    1989-01-01

    The new entropy concept for the collective magnetic equilibria is applied to the description of the states of a tokamak subject to ohmic and auxiliary heating. The condition for the existence of steady state plasma states with vanishing entropy production implies, on one hand, the resilience of specific current density profiles and, on the other, severe restrictions on the scaling of the confinement time with power and current. These restrictions are consistent with Goldston scaling and with the existence of a heat pinch. (author)

  6. Investigating sediment size distributions and size-specific Sm-Nd isotopes as paleoceanographic proxy in the North Atlantic Ocean: reconstructing past deep-sea current speeds since Last Glacial Maximum

    OpenAIRE

    Li, Yuting

    2017-01-01

    To explore whether the dispersion of sediments in the North Atlantic can be related to modern and past Atlantic Meridional Overturning Circulation (AMOC) flow speed, particle size distributions (weight%, Sortable Silt mean grain size) and grain-size separated (0–4, 4–10, 10–20, 20–30, 30–40 and 40–63 µm) Sm-Nd isotopes and trace element concentrations are measured on 12 cores along the flow-path of Western Boundary Undercurrent and in the central North Atlantic since the Last glacial Maximum ...

  7. Solar maximum mission

    International Nuclear Information System (INIS)

    Ryan, J.

    1981-01-01

    By understanding the sun, astrophysicists hope to expand this knowledge to understanding other stars. To study the sun, NASA launched a satellite on February 14, 1980. The project is named the Solar Maximum Mission (SMM). The satellite conducted detailed observations of the sun in collaboration with other satellites and ground-based optical and radio observations until its failure 10 months into the mission. The main objective of the SMM was to investigate one aspect of solar activity: solar flares. A brief description of the flare mechanism is given. The SMM satellite was valuable in providing information on where and how a solar flare occurs. A sequence of photographs of a solar flare taken from SMM satellite shows how a solar flare develops in a particular layer of the solar atmosphere. Two flares especially suitable for detailed observations by a joint effort occurred on April 30 and May 21 of 1980. These flares and observations of the flares are discussed. Also discussed are significant discoveries made by individual experiments

  8. Fourier-Based Transmit Beampattern Design Using MIMO Radar

    KAUST Repository

    Lipor, John

    2014-05-01

    In multiple-input multiple-output (MIMO) radar settings, it is often desirable to transmit power only to a given location or set of locations defined by a beampattern. Transmit waveform design is a topic that has received much attention recently, involving synthesis of both the signal covariance matrix,, as well as the actual waveforms. Current methods involve a two-step process of designing via iterative solutions and then using to generate waveforms that fulfill practical constraints such as having a constant-envelope or drawing from a finite alphabet. In this paper, a closed-form method to design for a uniform linear array is proposed that utilizes the discrete Fourier transform (DFT) coefficients and Toeplitz matrices. The resulting covariance matrix fulfills the practical constraints such as positive semidefiniteness and the uniformelemental power constraint and provides performance similar to that of iterative methods, which require a much greater computation time. Next, a transmit architecture is presented that exploits the orthogonality of frequencies at discrete DFT values to transmit a sum of orthogonal signals from each antenna. The resulting waveforms provide a lower mean-square error than current methods at a much lower computational cost, and a simulated detection scenario demonstrates the performance advantages achieved.

  9. Electron density distribution in Si and Ge using multipole, maximum ...

    Indian Academy of Sciences (India)

    Si and Ge has been studied using multipole, maximum entropy method (MEM) and ... and electron density distribution using the currently available versatile ..... data should be subjected to maximum possible utility for the characterization of.

  10. VIS-IR transmitting BGG glass windows

    Science.gov (United States)

    Bayya, Shyam S.; Chin, Geoff D.; Sanghera, Jasbinder S.; Aggarwal, Ishwar D.

    2003-09-01

    BaO-Ga2O3-GeO2 (BGG) glasses have the desired properties for various window applications in the 0.5-5 μm wavelength region. These glasses are low cost alternatives to the currently used window materials. Fabrication of a high optical quality 18" diameter BGG glass window has been demonstrated with a transmitted wave front error of λ/10 at 632 nm. BGG substrates have also been successfully tested for environmental weatherability (MIL-F-48616) and rain erosion durability up to 300 mph. Preliminary EMI grids have been successfully applied on BGG glasses demonstrating attenuation of 20dB in X and Ku bands. Although the mechanical properties of BGG glasses are acceptable for various window applications, it is demonstrated here that the properties can be further improved significantly by the glassceramization process. The ceramization process does not add any significant cost to the final window material. The crystallite size in the present glass-ceramic limits its transmission to the 2-5 μm region.

  11. Primary care management of sexually transmitted urethritis in adolescent males.

    Science.gov (United States)

    Lindberg, Claire E

    2003-04-01

    To describe current knowledge about diagnosis, screening, and treatment of sexually transmitted urethritis among adolescent and young adult males. Current research, systematic reviews, consensus guidelines and the author's clinical experience. Urethritis, the most common sexually transmitted syndrome in young males, is most frequently caused by Chlamydia trachomatis and/or Neisseria gonorrhea. Symptoms include dysuria and penile discharge, although up to 50% of males are asymptomatic. Risky sexual behaviors and lack of access to healthcare increase incidence of this infection. Transmission to female partners can lead to pelvic inflammatory disease, infertility, and neonatal infection. Young males with urethritis must be treated as soon as diagnosis is established. Consensus guidelines exist for diagnosis and treatment of gonococcal and non-gonococcal urethritis. Careful patient education is necessary to ensure successful treatment. Prevention of repeat infections requires partner treatment and detailed education about safer sexual practices. Improved access to preventive services for young males should be a healthcare priority.

  12. Imperfect generalized transmit beamforming with co-channel interference cancelation

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-10-01

    The performance of a generalized single-stream transmit beamforming scheme employing receive co-channel interference -steering algorithms in slowly varying and flat fading channels is analyzed. The impact of imperfect prediction of channel state information (CSI) for the desired user spatially uncorrelated transmit channels is considered. Both dominant interference cancelation and adaptive arbitrary interference cancelation algorithms for closely spaced receive antennas are used. The impact of outdated statistical ordering of the interferers instantaneous powers on the effectiveness of dominant interference cancelation is investigated against the less complex adaptive arbitrary cancelation scheme. For the system models described above, new exact formulas for the statistics of combined signal-to-interference-plus-noise ratio (SINR) are derived, from which results for conventional maximum ratio transmission (MRT) and best transmit channel selection schemes can be deduced as limiting cases. The results presented herein can be used to obtain quantitative measure for various performance metrics, and in addition to investigate the performance-complexity tradeoff for different multiple-antenna system models. © 2010 IEEE.

  13. Switch and examine transmit diversity for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed M.

    2011-06-01

    In this paper, we develop a switch and examine transmit diversity algorithm for spectrum sharing cognitive networks. We consider a cognitive network composed of a primary link that employs constant rate and constant power transmission scheme with automatic-and-repeat request (ARQ) protocol, while the secondary link is composed of a fixed power multiple-antenna secondary transmitter and a single antenna receiver. Our objective is to develop a low complex transmit diversity algorithm at the secondary transmitter that maximizes the performance of the secondary link in terms of the effective throughput while maintaining a predetermined maximum loss in the packet rate of the primary link. In achieving this objective, we develop an algorithm that selects the best antenna, which maintains the quality of the secondary link in terms of signal-to-noise ratio above a specific threshold, based on overhearing the acknowledgment (ACK) and negative acknowledgment (NACK) feedback messages transmitted over the primary link. We also develop closed form expressions for the bit error rates and the effective throughput of the secondary link. © 2011 IEEE.

  14. Transmit coil design for Wireless Power Transfer for medical implants.

    Science.gov (United States)

    Lemdiasov, Rosti; Venkatasubramanian, Arun

    2017-07-01

    A new design approach for the design of transmit coils for Wireless Power Transfer (WPT) is presented. The theoretical formulation involves a figure of merit that has to be maximized to solve for the surface current. Numerical predictions and comparisons with practical measurements for the coil parameters (inductance. resistance) underscore the success of this approach in terms of achieving strong coupling with a receive coil while maintaining low resistance.

  15. CDC WONDER: Sexually Transmitted Disease (STD) morbidity

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Sexually Transmitted Disease (STD) Morbidity online databases on CDC WONDER contain case reports reported from the 50 United States and D.C., Puerto Rico, Virgin...

  16. CDC WONDER: Sexually Transmitted Disease (STD) Morbidity

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Sexually Transmitted Disease (STD) Morbidity online databases on CDC WONDER contain case reports reported from the 50 United States and D.C., Puerto Rico, Virgin...

  17. Sexually Transmitted Diseases Surveillance, 2014: Syphilis

    Science.gov (United States)

    ... 2014 Sexually Transmitted Diseases Surveillance Table of Contents Introductory Section Foreword Preface Acronyms Figures- National Profile Figures – ... GISP Profiles Related Links STD Home STD Data & Statistics NCHHSTP Atlas Interactive STD Data – 1996-2013 STD ...

  18. The hidden epidemic: confronting sexually transmitted diseases

    National Research Council Canada - National Science Library

    Eng, Thomas R; Butler, William T

    .... In addition, STDs increase the risk of HIV transmission. The Hidden Epidemic examines the scope of sexually transmitted infections in the United States and provides a critical assessment of the nation's response to this public health crisis...

  19. Knowledge of Sexually Transmitted Diseases among Secondary ...

    African Journals Online (AJOL)

    The study was carried out in three public secondary schools in Ogbondoroko and Laduba .... population live in the rural areas where information on sexually transmitted ..... Centers for Disease Control and Prevention (2009) Diagnoses of HIV ...

  20. Analytical Model and Optimized Design of Power Transmitting Coil for Inductively Coupled Endoscope Robot.

    Science.gov (United States)

    Ke, Quan; Luo, Weijie; Yan, Guozheng; Yang, Kai

    2016-04-01

    A wireless power transfer system based on the weakly inductive coupling makes it possible to provide the endoscope microrobot (EMR) with infinite power. To facilitate the patients' inspection with the EMR system, the diameter of the transmitting coil is enlarged to 69 cm. Due to the large transmitting range, a high quality factor of the Litz-wire transmitting coil is a necessity to ensure the intensity of magnetic field generated efficiently. Thus, this paper builds an analytical model of the transmitting coil, and then, optimizes the parameters of the coil by enlarging the quality factor. The lumped model of the transmitting coil includes three parameters: ac resistance, self-inductance, and stray capacitance. Based on the exact two-dimension solution, the accurate analytical expression of ac resistance is derived. Several transmitting coils of different specifications are utilized to verify this analytical expression, being in good agreements with the measured results except the coils with a large number of strands. Then, the quality factor of transmitting coils can be well predicted with the available analytical expressions of self- inductance and stray capacitance. Owing to the exact estimation of quality factor, the appropriate coil turns of the transmitting coil is set to 18-40 within the restrictions of transmitting circuit and human tissue issues. To supply enough energy for the next generation of the EMR equipped with a Ø9.5×10.1 mm receiving coil, the coil turns of the transmitting coil is optimally set to 28, which can transfer a maximum power of 750 mW with the remarkable delivering efficiency of 3.55%.

  1. USACE AIS Transmit Technical Support Summary Report

    Science.gov (United States)

    2014-09-01

    the TAG block for the correct transmitters, and then send to the USACE AIS network. B. Outbound openings in the USCG firewall for the USCG Message...USACE AIS Transmit Technical Support Summary Report Distribution Statement A: Approved for public release; distribution is unlimited...September 2014 Report No. CD-D-09-15 USACE AIS Transmit Technical Support Summary Report ii UNCLAS//Public | CG-926 RDC | I. Gonin et al. Public

  2. Preliminary In-vivo Results For Spatially Coded Synthetic Transmit Aperture Ultrasound Based On Frequency Division

    DEFF Research Database (Denmark)

    Gran, Fredrik; Hansen, Kristoffer Lindskov; Jensen, Jørgen Arendt

    2006-01-01

    This paper investigates the possibility of using spatial coding based on frequency division for in-vivo synthetic transmit aperture (STA) ultrasound imaging. When using spatial encoding for STA, it is possible to use several transmitters simultaneously and separate the signals at the receiver....... This increases the maximum transmit power compared to conventional STA, where only one transmitter can be active. The signal-to-noise-ratio can therefore he increased and better penetration can be obtained. For frequency division, the coding is achieved by designing a number of transmit waveforms with disjoint...... spectral support, spanning the passband of the ultrasound transducer. The signals can therefore he separated at the receiver using matched filtering. The method is tested using a commercial linear array transducer with a center frequency of 9 MHz and 68% fractional bandwidth. In this paper, the transmit...

  3. Credal Networks under Maximum Entropy

    OpenAIRE

    Lukasiewicz, Thomas

    2013-01-01

    We apply the principle of maximum entropy to select a unique joint probability distribution from the set of all joint probability distributions specified by a credal network. In detail, we start by showing that the unique joint distribution of a Bayesian tree coincides with the maximum entropy model of its conditional distributions. This result, however, does not hold anymore for general Bayesian networks. We thus present a new kind of maximum entropy models, which are computed sequentially. ...

  4. Ocular Manifestations of Mosquito-Transmitted Diseases.

    Science.gov (United States)

    Karesh, James W; Mazzoli, Robert A; Heintz, Shannon K

    2018-03-01

    Of the 3,548 known mosquito species, about 100 transmit human diseases. Mosquitoes are distributed globally throughout tropical and temperate regions where standing water sources are available for egg laying and the maturation of larva. Female mosquitoes require blood meals for egg production. This is the main pathway for disease transmission. Mosquitoes carry several pathogenic organisms responsible for significant ocular pathology and vision loss including West Nile, Rift Valley, chikungunya, dengue viruses, various encephalitis viruses, malarial parasites, Francisella tularensis, microfilarial parasites, including Dirofilaria, Wuchereria, and Brugia spp., and human botfly larvae. Health care providers may not be familiar with many of these mosquito-transmitted diseases or their associated ocular findings delaying diagnosis, treatment, and recovery of visual function. This article aims to provide an overview of the ocular manifestations associated with mosquito-transmitted diseases.

  5. Adaptive transmit selection with interference suppression

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2010-01-01

    This paper studies the performance of adaptive transmit channel selection in multipath fading channels. The adaptive selection algorithms are configured for single-antenna bandwidth-efficient or power-efficient transmission with as low transmit channel estimations as possible. Due to the fact that the number of active co-channel interfering signals and their corresponding powers experience random behavior, the adaptation to channels conditions, assuming uniform buffer and traffic loading, is proposed to be jointly based on the transmit channels instantaneous signal-to-noise ratios (SNRs) and signal-to- interference-plus- noise ratios (SINRs). Two interference cancelation algorithms, which are the dominant cancelation and the less complex arbitrary cancelation, are considered, for which the receive antenna array is assumed to have small angular spread. Analytical formulation for some performance measures in addition to several processing complexity and numerical comparisons between various adaptation schemes are presented. ©2010 IEEE.

  6. Syndromes Associated with Sexually Transmitted Infections

    Directory of Open Access Journals (Sweden)

    Max Chernesky

    2005-01-01

    Full Text Available Excellent technologies have been developed to identify the specific microbial agents of chlamydia, gonorrhea, syphilis, herpes, chancroid, trichomoniasis, human papillomavirus and HIV infection. However, it is also crucial to recognize syndromes that may be caused by one or more sexually transmitted pathogens. When laboratory services are lacking or are inadequate to provide timely results to enable appropriate treatment, some patients must be managed and treated syndromically. Most Canadian laboratories should be able to provide diagnostic services to determine the etiology of syndromes such as cervicitis, urethritis, pelvic inflammatory disease, prostatitis, genital ulcers, sexually transmitted infection (STI-related enteric infections, epididymitis, hepatitis, ophthalmia neonatorum, vulvovaginitis and vaginosis.

  7. On reflectionless equi-transmitting matrices

    Directory of Open Access Journals (Sweden)

    Pavel Kurasov

    2014-01-01

    Full Text Available Reflectionless equi-transmitting unitary matrices are studied in connection to matching conditions in quantum graphs. All possible such matrices of size 6 are described explicitly. It is shown that such matrices form 30 six-parameter families intersected along 12 five-parameter families closely connected to conference matrices.

  8. The hidden epidemic: confronting sexually transmitted diseases

    National Research Council Canada - National Science Library

    Eng, Thomas R; Butler, William T

    ... of Sexually Transmitted Diseases INSTITUTE OF MEDICINE Division of Health Promotion and Disease Prevention NATIONAL ACADEMY PRESS Washington, D.C. 1997 Copyrightthe cannot be not from book, paper however, version for formatting, original authoritative the typesetting-specific the as from created publication files XML from other this ...

  9. [Condom effectiveness to prevent sexually transmitted diseases].

    Science.gov (United States)

    Vera, Eduardo Gayón; Orozco, Hilda Hernández; Soto, Selene Sam; Aburto, Esther Lombardo

    2008-02-01

    Sexual transmitted diseases (included HIV/AIDS) are a common and preventable cause of perinatal morbidity and mortality. When used consistently and correctly, condoms are effective to prevent these diseases, however, its protection does not account for 100%. To know the effectiveness of male condom, through bibliographic evidence, to prevent sexual transmitted infections in heterosexual serodiscordant partners. A bibliographical review of Medline/Pubmed, LILACS and Cochrane databases, and publications of the National Health Institutes, Centers for Disease Control and Prevention, World Health Organization, and WHO AIDS Global Program was done to analyze male condom effectiveness to prevent sexual transmitted diseases. Reports demonstrated that male condom protection against HIV/AIDS in heterosexual serodiscordant partners goes from 60 to 95%. Most recent information (2006) showed 80%. Two studies demonstrated no HPV protection with male condom, and another one 70% of protection. Male condom demonstrated no HPV-1 protection, but decrease of risk in HVS-2 transmission in women (0.85 of protection). Male condom protection against sexual transmitted diseases is not 100%. There must be used additional measures that have demonstrated its utility to decrease transmission risk.

  10. Vulnerability and Knowledge of Sexually Transmitted Infections ...

    African Journals Online (AJOL)

    Vulnerability and Knowledge of Sexually Transmitted Infections Among Female Traders of Reproductive Age in Enugu, Nigeria. ... Conclusion: The inclusion of health education in schools' curricula to ensure that adolescents are adequately aware of STIs, their modes of transmission, prevention and treatment before ...

  11. Inductive Reasoning about Causally Transmitted Properties

    Science.gov (United States)

    Shafto, Patrick; Kemp, Charles; Bonawitz, Elizabeth Baraff; Coley, John D.; Tenenbaum, Joshua B.

    2008-01-01

    Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates'…

  12. Evaluation of transmitted images by teleradiology system

    International Nuclear Information System (INIS)

    Hoshikawa, Yoshikazu

    1993-01-01

    Teleradiology system is a combination of digital data networks and computer systems, which is the electric transmission of radiographs and/or radiologic images from local to center radiological system. The author evaluated reproducibility of transmitted images using Photophone (Image Data Corporation) as teleradiology system. Proven cases of abdominal free air (38 plain films, 15 CT), pneumothorax (24 plain films, 20 CT) and small bowel obstruction (30 plain films, 8 CT) were transmitted. Findings could be identified on non-magnified plain films in 75.6%, 83.3% and 96.7% respectively and on magnified CT in 100%, 100% and 100%. Transmitted images of 57 cases of abdominal trauma were read for positive findings and diagnosis by three radiologists. Average positive ratio was 47.3% on plain films and 70.9% on CT. Diagnosis was correct in 66.7% on CT. Specificity and sensitivity were 81.9% and 61.6% respectively on plain film and 88.6% and 93.9% on CT. The accuracy of transmitted images appears to be unsatisfactory on this study. It is suggested that the system is useful for consultation of already identified findings on the original images. (author)

  13. Evaluation of transmitted images by teleradiology system

    Energy Technology Data Exchange (ETDEWEB)

    Hoshikawa, Yoshikazu (St. Marianna Univ., Kawasaki (Japan). School of Medicine)

    1993-12-01

    Teleradiology system is a combination of digital data networks and computer systems, which is the electric transmission of radiographs and/or radiologic images from local to center radiological system. The author evaluated reproducibility of transmitted images using Photophone (Image Data Corporation) as teleradiology system. Proven cases of abdominal free air (38 plain films, 15 CT), pneumothorax (24 plain films, 20 CT) and small bowel obstruction (30 plain films, 8 CT) were transmitted. Findings could be identified on non-magnified plain films in 75.6%, 83.3% and 96.7% respectively and on magnified CT in 100%, 100% and 100%. Transmitted images of 57 cases of abdominal trauma were read for positive findings and diagnosis by three radiologists. Average positive ratio was 47.3% on plain films and 70.9% on CT. Diagnosis was correct in 66.7% on CT. Specificity and sensitivity were 81.9% and 61.6% respectively on plain film and 88.6% and 93.9% on CT. The accuracy of transmitted images appears to be unsatisfactory on this study. It is suggested that the system is useful for consultation of already identified findings on the original images. (author).

  14. Knowledge of sexually transmitted diseases among secondary ...

    African Journals Online (AJOL)

    Background: Sexually Transmitted Diseases (STDs) are a major health problem affecting mostly young people in both developed and developing countries. Insufficient knowledge about STDs is a major impediment to successfully prevent the diseases among adolescent populations in developing countries. Objective: To ...

  15. Soil transmitted helminths infections, malnutrition and anaemia ...

    African Journals Online (AJOL)

    Soil-transmitted helminths (STHs) are a major public health problem in many developing countries. Establishment of prevalence and intensity of infections is important in designing, implementating and evaluating control programs. This study aimed at determining the prevalence and intensity of STH infections, malnutrition ...

  16. MIMO transmit scheme based on morphological perceptron with competitive learning.

    Science.gov (United States)

    Valente, Raul Ambrozio; Abrão, Taufik

    2016-08-01

    This paper proposes a new multi-input multi-output (MIMO) transmit scheme aided by artificial neural network (ANN). The morphological perceptron with competitive learning (MP/CL) concept is deployed as a decision rule in the MIMO detection stage. The proposed MIMO transmission scheme is able to achieve double spectral efficiency; hence, in each time-slot the receiver decodes two symbols at a time instead one as Alamouti scheme. Other advantage of the proposed transmit scheme with MP/CL-aided detector is its polynomial complexity according to modulation order, while it becomes linear when the data stream length is greater than modulation order. The performance of the proposed scheme is compared to the traditional MIMO schemes, namely Alamouti scheme and maximum-likelihood MIMO (ML-MIMO) detector. Also, the proposed scheme is evaluated in a scenario with variable channel information along the frame. Numerical results have shown that the diversity gain under space-time coding Alamouti scheme is partially lost, which slightly reduces the bit-error rate (BER) performance of the proposed MP/CL-NN MIMO scheme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Analysis of the local worst-case SAR exposure caused by an MRI multi-transmit body coil in anatomical models of the human body

    International Nuclear Information System (INIS)

    Neufeld, Esra; Gosselin, Marie-Christine; Murbach, Manuel; Christ, Andreas; Cabot, Eugenia; Kuster, Niels

    2011-01-01

    Multi-transmit coils are increasingly being employed in high-field magnetic resonance imaging, along with a growing interest in multi-transmit body coils. However, they can lead to an increase in whole-body and local specific absorption rate (SAR) compared to conventional body coils excited in circular polarization for the same total incident input power. In this study, the maximum increase of SAR for three significantly different human anatomies is investigated for a large 3 T (128 MHz) multi-transmit body coil using numerical simulations and a (generalized) eigenvalue-based approach. The results demonstrate that the increase of SAR strongly depends on the anatomy. For the three models and normalization to the sum of the rung currents squared, the whole-body averaged SAR increases by up to a factor of 1.6 compared to conventional excitation and the peak spatial SAR (averaged over any 10 cm 3 of tissue) by up to 13.4. For some locations the local averaged SAR goes up as much as 800 times (130 when looking only at regions where it is above 1% of the peak spatial SAR). The ratio of the peak spatial SAR to the whole-body SAR increases by a factor of up to 47 and can reach values above 800. Due to the potentially much larger power deposition, additional, preferably patient-specific, considerations are necessary to avoid injuries by such systems.

  18. Analysis of the local worst-case SAR exposure caused by an MRI multi-transmit body coil in anatomical models of the human body

    Energy Technology Data Exchange (ETDEWEB)

    Neufeld, Esra; Gosselin, Marie-Christine; Murbach, Manuel; Christ, Andreas; Cabot, Eugenia; Kuster, Niels, E-mail: neufeld@itis.ethz.ch [Foundation for Research on Information Technologies in Society (IT' IS), Zeughausstr. 43, 8004 Zuerich (Switzerland)

    2011-08-07

    Multi-transmit coils are increasingly being employed in high-field magnetic resonance imaging, along with a growing interest in multi-transmit body coils. However, they can lead to an increase in whole-body and local specific absorption rate (SAR) compared to conventional body coils excited in circular polarization for the same total incident input power. In this study, the maximum increase of SAR for three significantly different human anatomies is investigated for a large 3 T (128 MHz) multi-transmit body coil using numerical simulations and a (generalized) eigenvalue-based approach. The results demonstrate that the increase of SAR strongly depends on the anatomy. For the three models and normalization to the sum of the rung currents squared, the whole-body averaged SAR increases by up to a factor of 1.6 compared to conventional excitation and the peak spatial SAR (averaged over any 10 cm{sup 3} of tissue) by up to 13.4. For some locations the local averaged SAR goes up as much as 800 times (130 when looking only at regions where it is above 1% of the peak spatial SAR). The ratio of the peak spatial SAR to the whole-body SAR increases by a factor of up to 47 and can reach values above 800. Due to the potentially much larger power deposition, additional, preferably patient-specific, considerations are necessary to avoid injuries by such systems.

  19. [Diseases transmitted through water for human consumption].

    Science.gov (United States)

    Franco, E; Dentamaro, M

    2003-01-01

    The water for human consumption maintains a biological risk and can transmit diseases. The classical waterborne and the presently frequent diseases caused by protozoi Giardia and Cryptosporidium are considered and Arcobacter butzleri, a new waterborne pathogen, is described. Many measures have been adopted by institutions to ensure the quality of the drinking water. Managers and public health operators is working in order to verify the efficiency of more suitable indicators for its monitoring.

  20. Impact of sensing errors on the queueing delay and transmit power in cognitive radio access

    KAUST Repository

    Hamza, Doha R.; Aissa, Sonia

    2011-01-01

    We study a multiple-access system with a primary user (PU) and a secondary user (SU) utilizing the same frequency band and communicating with a common receiver. Both users transmit with a fixed transmission rate by employing a channel inversion power control scheme. The SU transmits with a certain probability that depends on the sensing outcome, its queue length and whether it has a new packet arrival. We consider the case of erroneous sensing. The goal of the SU is to find the optimal transmission scheduling policy so as to minimize its queueing delay under constraints on its average transmit power and the maximum tolerable primary outage probability caused by miss-detection. The access probabilities are obtained efficiently using linear programming. © 2011 IEEE.

  1. Impact of sensing errors on the queueing delay and transmit power in cognitive radio access

    KAUST Repository

    Hamza, Doha R.

    2011-03-01

    We study a multiple-access system with a primary user (PU) and a secondary user (SU) utilizing the same frequency band and communicating with a common receiver. Both users transmit with a fixed transmission rate by employing a channel inversion power control scheme. The SU transmits with a certain probability that depends on the sensing outcome, its queue length and whether it has a new packet arrival. We consider the case of erroneous sensing. The goal of the SU is to find the optimal transmission scheduling policy so as to minimize its queueing delay under constraints on its average transmit power and the maximum tolerable primary outage probability caused by miss-detection. The access probabilities are obtained efficiently using linear programming. © 2011 IEEE.

  2. Circuit design and simulation of a transmit beamforming ASIC for high-frequency ultrasonic imaging systems.

    Science.gov (United States)

    Athanasopoulos, Georgios I; Carey, Stephen J; Hatfield, John V

    2011-07-01

    This paper describes the design of a programmable transmit beamformer application-specific integrated circuit (ASIC) with 8 channels for ultrasound imaging systems. The system uses a 20-MHz reference clock. A digital delay-locked loop (DLL) was designed with 50 variable delay elements, each of which provides a clock with different phase from a single reference. Two phase detectors compare the phase difference of the reference clock with the feedback clock, adjusting the delay of the delay elements to bring the feedback clock signal in phase with the reference clock signal. Two independent control voltages for the delay elements ensure that the mark space ratio of the pulses remain at 50%. By combining a 10- bit asynchronous counter with the delays from the DLL, each channel can be programmed to give a maximum time delay of 51 μs with 1 ns resolution. It can also give bursts of up to 64 pulses. Finally, for a single pulse, it can adjust the pulse width between 9 ns and 100 ns by controlling the current flowing through a capacitor in a one-shot circuit, for use with 40-MHz and 5-MHz transducers, respectively.

  3. Maximum stellar iron core mass

    Indian Academy of Sciences (India)

    60, No. 3. — journal of. March 2003 physics pp. 415–422. Maximum stellar iron core mass. F W GIACOBBE. Chicago Research Center/American Air Liquide ... iron core compression due to the weight of non-ferrous matter overlying the iron cores within large .... thermal equilibrium velocities will tend to be non-relativistic.

  4. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore. 11 refs., 4 figs

  5. Maximum entropy beam diagnostic tomography

    International Nuclear Information System (INIS)

    Mottershead, C.T.

    1985-01-01

    This paper reviews the formalism of maximum entropy beam diagnostic tomography as applied to the Fusion Materials Irradiation Test (FMIT) prototype accelerator. The same formalism has also been used with streak camera data to produce an ultrahigh speed movie of the beam profile of the Experimental Test Accelerator (ETA) at Livermore

  6. A portable storage maximum thermometer

    International Nuclear Information System (INIS)

    Fayart, Gerard.

    1976-01-01

    A clinical thermometer storing the voltage corresponding to the maximum temperature in an analog memory is described. End of the measurement is shown by a lamp switch out. The measurement time is shortened by means of a low thermal inertia platinum probe. This portable thermometer is fitted with cell test and calibration system [fr

  7. Neutron spectra unfolding with maximum entropy and maximum likelihood

    International Nuclear Information System (INIS)

    Itoh, Shikoh; Tsunoda, Toshiharu

    1989-01-01

    A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

  8. Super-Orthogonal Space-Time Turbo Transmit Diversity for CDMA

    Directory of Open Access Journals (Sweden)

    Pieter G. W. van Rooyen

    2005-05-01

    Full Text Available Studies have shown that transmit and receive diversity employing a combination of multiple transmit-receive antennas (given ideal channel state information (CSI and independent fading between antenna pairs will potentially yield maximum achievable system capacity. In this paper, the concept of a layered super-orthogonal turbo transmit diversity (SOTTD for downlink direct-sequence code-division multiple-access (CDMA systems is explored. This open-loop transmit diversity technique improves the downlink performance by using a small number of antenna elements at the base station and a single antenna at the handset. In the proposed technique, low-rate super-orthogonal code-spread CDMA is married with code-division transmit diversity (CDTD. At the mobile receiver, space-time (ST RAKE CDTD processing is combined with iterative turbo code-spread decoding to yield large ST gains. The performance of the SOTTD system is compared with single- and multiantenna turbo-coded (TC CDTD systems evaluated over a frequency-selective Rayleigh fading channel. The evaluation is done both by means of analysis and computer simulations. The performance results illustrate the superior performance of SOTTD compared to TC CDTD systems over practically the complete useful capacity range of CDMA. It is shown that the performance degradation characteristic of TC CDTD at low system loads (due to the inherent TC error floor is alleviated by the SOTTD system.

  9. Microprocessor Controlled Maximum Power Point Tracker for Photovoltaic Application

    International Nuclear Information System (INIS)

    Jiya, J. D.; Tahirou, G.

    2002-01-01

    This paper presents a microprocessor controlled maximum power point tracker for photovoltaic module. Input current and voltage are measured and multiplied within the microprocessor, which contains an algorithm to seek the maximum power point. The duly cycle of the DC-DC converter, at which the maximum power occurs is obtained, noted and adjusted. The microprocessor constantly seeks for improvement of obtained power by varying the duty cycle

  10. Stochastic dynamics for reinfection by transmitted diseases

    Science.gov (United States)

    Barros, Alessandro S.; Pinho, Suani T. R.

    2017-06-01

    The use of stochastic models to study the dynamics of infectious diseases is an important tool to understand the epidemiological process. For several directly transmitted diseases, reinfection is a relevant process, which can be expressed by endogenous reactivation of the pathogen or by exogenous reinfection due to direct contact with an infected individual (with smaller reinfection rate σ β than infection rate β ). In this paper, we examine the stochastic susceptible, infected, recovered, infected (SIRI) model simulating the endogenous reactivation by a spontaneous reaction, while exogenous reinfection by a catalytic reaction. Analyzing the mean-field approximations of a site and pairs of sites, and Monte Carlo (MC) simulations for the particular case of exogenous reinfection, we obtained continuous phase transitions involving endemic, epidemic, and no transmission phases for the simple approach; the approach of pairs is better to describe the phase transition from endemic phase (susceptible, infected, susceptible (SIS)-like model) to epidemic phase (susceptible, infected, and removed or recovered (SIR)-like model) considering the comparison with MC results; the reinfection increases the peaks of outbreaks until the system reaches endemic phase. For the particular case of endogenous reactivation, the approach of pairs leads to a continuous phase transition from endemic phase (SIS-like model) to no transmission phase. Finally, there is no phase transition when both effects are taken into account. We hope the results of this study can be generalized for the susceptible, exposed, infected, and removed or recovered (SEIRIE) model, for which the state exposed (infected but not infectious), describing more realistically transmitted diseases such as tuberculosis. In future work, we also intend to investigate the effect of network topology on phase transitions when the SIRI model describes both transmitted diseases (σ social contagions (σ >1 ).

  11. On Maximum Entropy and Inference

    Directory of Open Access Journals (Sweden)

    Luigi Gresele

    2017-11-01

    Full Text Available Maximum entropy is a powerful concept that entails a sharp separation between relevant and irrelevant variables. It is typically invoked in inference, once an assumption is made on what the relevant variables are, in order to estimate a model from data, that affords predictions on all other (dependent variables. Conversely, maximum entropy can be invoked to retrieve the relevant variables (sufficient statistics directly from the data, once a model is identified by Bayesian model selection. We explore this approach in the case of spin models with interactions of arbitrary order, and we discuss how relevant interactions can be inferred. In this perspective, the dimensionality of the inference problem is not set by the number of parameters in the model, but by the frequency distribution of the data. We illustrate the method showing its ability to recover the correct model in a few prototype cases and discuss its application on a real dataset.

  12. Maximum-Likelihood Sequence Detection of Multiple Antenna Systems over Dispersive Channels via Sphere Decoding

    Directory of Open Access Journals (Sweden)

    Hassibi Babak

    2002-01-01

    Full Text Available Multiple antenna systems are capable of providing high data rate transmissions over wireless channels. When the channels are dispersive, the signal at each receive antenna is a combination of both the current and past symbols sent from all transmit antennas corrupted by noise. The optimal receiver is a maximum-likelihood sequence detector and is often considered to be practically infeasible due to high computational complexity (exponential in number of antennas and channel memory. Therefore, in practice, one often settles for a less complex suboptimal receiver structure, typically with an equalizer meant to suppress both the intersymbol and interuser interference, followed by the decoder. We propose a sphere decoding for the sequence detection in multiple antenna communication systems over dispersive channels. The sphere decoding provides the maximum-likelihood estimate with computational complexity comparable to the standard space-time decision-feedback equalizing (DFE algorithms. The performance and complexity of the sphere decoding are compared with the DFE algorithm by means of simulations.

  13. Maximum Water Hammer Sensitivity Analysis

    OpenAIRE

    Jalil Emadi; Abbas Solemani

    2011-01-01

    Pressure waves and Water Hammer occur in a pumping system when valves are closed or opened suddenly or in the case of sudden failure of pumps. Determination of maximum water hammer is considered one of the most important technical and economical items of which engineers and designers of pumping stations and conveyance pipelines should take care. Hammer Software is a recent application used to simulate water hammer. The present study focuses on determining significance of ...

  14. Maximum Gene-Support Tree

    Directory of Open Access Journals (Sweden)

    Yunfeng Shan

    2008-01-01

    Full Text Available Genomes and genes diversify during evolution; however, it is unclear to what extent genes still retain the relationship among species. Model species for molecular phylogenetic studies include yeasts and viruses whose genomes were sequenced as well as plants that have the fossil-supported true phylogenetic trees available. In this study, we generated single gene trees of seven yeast species as well as single gene trees of nine baculovirus species using all the orthologous genes among the species compared. Homologous genes among seven known plants were used for validation of the finding. Four algorithms—maximum parsimony (MP, minimum evolution (ME, maximum likelihood (ML, and neighbor-joining (NJ—were used. Trees were reconstructed before and after weighting the DNA and protein sequence lengths among genes. Rarely a gene can always generate the “true tree” by all the four algorithms. However, the most frequent gene tree, termed “maximum gene-support tree” (MGS tree, or WMGS tree for the weighted one, in yeasts, baculoviruses, or plants was consistently found to be the “true tree” among the species. The results provide insights into the overall degree of divergence of orthologous genes of the genomes analyzed and suggest the following: 1 The true tree relationship among the species studied is still maintained by the largest group of orthologous genes; 2 There are usually more orthologous genes with higher similarities between genetically closer species than between genetically more distant ones; and 3 The maximum gene-support tree reflects the phylogenetic relationship among species in comparison.

  15. LCLS Maximum Credible Beam Power

    International Nuclear Information System (INIS)

    Clendenin, J.

    2005-01-01

    The maximum credible beam power is defined as the highest credible average beam power that the accelerator can deliver to the point in question, given the laws of physics, the beam line design, and assuming all protection devices have failed. For a new accelerator project, the official maximum credible beam power is determined by project staff in consultation with the Radiation Physics Department, after examining the arguments and evidence presented by the appropriate accelerator physicist(s) and beam line engineers. The definitive parameter becomes part of the project's safety envelope. This technical note will first review the studies that were done for the Gun Test Facility (GTF) at SSRL, where a photoinjector similar to the one proposed for the LCLS is being tested. In Section 3 the maximum charge out of the gun for a single rf pulse is calculated. In Section 4, PARMELA simulations are used to track the beam from the gun to the end of the photoinjector. Finally in Section 5 the beam through the matching section and injected into Linac-1 is discussed

  16. Sexually Transmitted Diseases Treatment Guidelines, 2015

    Science.gov (United States)

    Workowski, Kimberly A.; Bolan, Gail A.

    2016-01-01

    Summary These guidelines for the treatment of persons who have or are at risk for sexually transmitted diseases (STDs) were updated by CDC after consultation with a group of professionals knowledgeable in the field of STDs who met in Atlanta on April 30–May 2, 2013. The information in this report updates the Sexually Transmitted Diseases Treatment Guidelines, 2010 (MMWR Recomm Rep 2010;59 [No. RR–12]). These updated guidelines discuss 1) alternative treatment regimens for Neisseria gonorrhoeae; 2) the use of nucleic acid amplification tests for the diagnosis of trichomoniasis; 3) alternative treatment options for genital warts; 4) the role of Mycoplasma genitalium in urethritis/cervicitis and treatment-related implications; 5) updated HPV vaccine recommendations and counseling messages; 6) the management of persons who are transgender; 7) annual testing for hepatitis C in persons with HIV infection; 8) updated recommendations for diagnostic evaluation of urethritis; and 9) retesting to detect repeat infection. Physicians and other health-care providers can use these guidelines to assist in the prevention and treatment of STDs. PMID:26042815

  17. Multiple routes transmitted epidemics on multiplex networks

    International Nuclear Information System (INIS)

    Zhao, Dawei; Li, Lixiang; Peng, Haipeng; Luo, Qun; Yang, Yixian

    2014-01-01

    This letter investigates the multiple routes transmitted epidemic process on multiplex networks. We propose detailed theoretical analysis that allows us to accurately calculate the epidemic threshold and outbreak size. It is found that the epidemic can spread across the multiplex network even if all the network layers are well below their respective epidemic thresholds. Strong positive degree–degree correlation of nodes in multiplex network could lead to a much lower epidemic threshold and a relatively smaller outbreak size. However, the average similarity of neighbors from different layers of nodes has no obvious effect on the epidemic threshold and outbreak size. -- Highlights: •We studies multiple routes transmitted epidemic process on multiplex networks. •SIR model and bond percolation theory are used to analyze the epidemic processes. •We derive equations to accurately calculate the epidemic threshold and outbreak size. •ASN has no effect on the epidemic threshold and outbreak size. •Strong positive DDC leads to a lower epidemic threshold and a smaller outbreak size.

  18. Multiple routes transmitted epidemics on multiplex networks

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Dawei [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Shandong Provincial Key Laboratory of Computer Network, Shandong Computer Science Center, Jinan 250014 (China); Li, Lixiang [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Peng, Haipeng, E-mail: penghaipeng@bupt.edu.cn [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Luo, Qun; Yang, Yixian [Information Security Center, State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, P.O. Box 145, Beijing 100876 (China); National Engineering Laboratory for Disaster Backup and Recovery, Beijing University of Posts and Telecommunications, Beijing 100876 (China)

    2014-02-01

    This letter investigates the multiple routes transmitted epidemic process on multiplex networks. We propose detailed theoretical analysis that allows us to accurately calculate the epidemic threshold and outbreak size. It is found that the epidemic can spread across the multiplex network even if all the network layers are well below their respective epidemic thresholds. Strong positive degree–degree correlation of nodes in multiplex network could lead to a much lower epidemic threshold and a relatively smaller outbreak size. However, the average similarity of neighbors from different layers of nodes has no obvious effect on the epidemic threshold and outbreak size. -- Highlights: •We studies multiple routes transmitted epidemic process on multiplex networks. •SIR model and bond percolation theory are used to analyze the epidemic processes. •We derive equations to accurately calculate the epidemic threshold and outbreak size. •ASN has no effect on the epidemic threshold and outbreak size. •Strong positive DDC leads to a lower epidemic threshold and a smaller outbreak size.

  19. Improved Maximum Parsimony Models for Phylogenetic Networks.

    Science.gov (United States)

    Van Iersel, Leo; Jones, Mark; Scornavacca, Celine

    2018-05-01

    Phylogenetic networks are well suited to represent evolutionary histories comprising reticulate evolution. Several methods aiming at reconstructing explicit phylogenetic networks have been developed in the last two decades. In this article, we propose a new definition of maximum parsimony for phylogenetic networks that permits to model biological scenarios that cannot be modeled by the definitions currently present in the literature (namely, the "hardwired" and "softwired" parsimony). Building on this new definition, we provide several algorithmic results that lay the foundations for new parsimony-based methods for phylogenetic network reconstruction.

  20. Generic maximum likely scale selection

    DEFF Research Database (Denmark)

    Pedersen, Kim Steenstrup; Loog, Marco; Markussen, Bo

    2007-01-01

    in this work is on applying this selection principle under a Brownian image model. This image model provides a simple scale invariant prior for natural images and we provide illustrative examples of the behavior of our scale estimation on such images. In these illustrative examples, estimation is based......The fundamental problem of local scale selection is addressed by means of a novel principle, which is based on maximum likelihood estimation. The principle is generally applicable to a broad variety of image models and descriptors, and provides a generic scale estimation methodology. The focus...

  1. Extreme Maximum Land Surface Temperatures.

    Science.gov (United States)

    Garratt, J. R.

    1992-09-01

    There are numerous reports in the literature of observations of land surface temperatures. Some of these, almost all made in situ, reveal maximum values in the 50°-70°C range, with a few, made in desert regions, near 80°C. Consideration of a simplified form of the surface energy balance equation, utilizing likely upper values of absorbed shortwave flux (1000 W m2) and screen air temperature (55°C), that surface temperatures in the vicinity of 90°-100°C may occur for dry, darkish soils of low thermal conductivity (0.1-0.2 W m1 K1). Numerical simulations confirm this and suggest that temperature gradients in the first few centimeters of soil may reach 0.5°-1°C mm1 under these extreme conditions. The study bears upon the intrinsic interest of identifying extreme maximum temperatures and yields interesting information regarding the comfort zone of animals (including man).

  2. The other epidemics. Sexually transmitted diseases.

    Science.gov (United States)

    Jacobson, J L

    1993-01-01

    Around 70% of female infertility in developing countries is caused by sexually transmitted diseases (STDs) that can be traced back to husbands or partners. STDs and reproductive tract infections cause 750,000 deaths and 75 million illnesses among women each year worldwide, and these deaths may more than double by the year 2000. Death rates are rising fastest in Africa, followed by Asia and Latin America. About 450,000 cases of potentially fatal reproductive tract cancers are diagnosed annually: an estimated 354,000 occur in Third World women, virtually all of whom die. Worldwide, roughly 250 million new infections of chlamydia, gonorrhea, and the human papillomavirus are sexually transmitted each year. Chlamydia and the human papillomavirus account for 50 million and 30 million new cases per year, respectively. The human immunodeficiency virus (HIV) infected 1 million people worldwide between April and December 1991, according to the World Health Organization. A study in the Indian state of Maharashtra revealed that 92% of the 650 rural women examined had an average of 3.6 infections of gynecological type or sexually transmitted type per women. Another study in 2 rural Egyptian villages found that half of 509 nonpregnant women aged 20 to 60 years had infections. Only 2 facilities for the diagnosis and treatment of STDs exist in all of Kenya. In Ibadan, Nigeria, with a population of 2 million, there is only 1 recognized STD clinic. The physical consequences of several STDs have been linked to increased risks of AIDS transmission. Early recognition and treatment of STDs in pregnant women would cut infant mortality. Maternal infections with chlamydia, gonorrhea, or herpes are transferred to infants at birth 25% to 50% of the time. In Africa, infant blindness caused by gonorrhea infection is 50 times more common than in industrial countries. The International Women's Health Coalition's March 1992 meeting of more than 50 Third World scientists, health advocates, and

  3. A Simple Differential Modulation Scheme for Quasi-Orthogonal Space-Time Block Codes with Partial Transmit Diversity

    Directory of Open Access Journals (Sweden)

    Lingyang Song

    2007-04-01

    Full Text Available We report a simple differential modulation scheme for quasi-orthogonal space-time block codes. A new class of quasi-orthogonal coding structures that can provide partial transmit diversity is presented for various numbers of transmit antennas. Differential encoding and decoding can be simplified for differential Alamouti-like codes by grouping the signals in the transmitted matrix and decoupling the detection of data symbols, respectively. The new scheme can achieve constant amplitude of transmitted signals, and avoid signal constellation expansion; in addition it has a linear signal detector with very low complexity. Simulation results show that these partial-diversity codes can provide very useful results at low SNR for current communication systems. Extension to more than four transmit antennas is also considered.

  4. On the diversity enhancement and power balancing of per-subcarrier transmit antenna selection in OFDM systems

    KAUST Repository

    Park, Kihong; Ko, Youngchai; Alouini, Mohamed-Slim

    2011-01-01

    to the channel variation per subcarrier, we develop an optimal transmit antenna selection scheme in terms of the maximum spectral efficiency, where all the possible groupings for sending the same information-bearing signals in a group of subcarriers are searched

  5. Closed form fourier-based transmit beamforming for MIMO radar

    KAUST Repository

    Lipor, John J.

    2014-05-01

    In multiple-input multiple-output (MIMO) radar setting, it is often desirable to design correlated waveforms such that power is transmitted only to a given set of locations, a process known as beampattern design. To design desired beam-pattern, current research uses iterative algorithms, first to synthesize the waveform covariance matrix, R, then to design the actual waveforms to realize R. In contrast to this, we present a closed form method to design R that exploits discrete Fourier transform and Toeplitz matrix. The resulting covariance matrix fulfills the practical constraints and performance is similar to that of iterative methods. Next, we present a radar architecture for the desired beampattern that does not require the synthesis of covariance matrix nor the design of correlated waveforms. © 2014 IEEE.

  6. Social determinants and sexually transmitted disease disparities.

    Science.gov (United States)

    Hogben, Matthew; Leichliter, Jami S

    2008-12-01

    Social determinants of health play an important role in sexually transmitted disease (STD) transmission and acquisition; consequently, racial and ethnic disparities among social determinants are influences upon disparities in STD rates. In this narrative review, we outline a general model showing the relationship between social determinants and STD outcomes, mediated by epidemiologic context. We then review 4 specific social determinants relevant to STD disparities: segregation, health care, socioeconomics and correctional experiences, followed by 2 facets of the resultant epidemiologic context: core areas and sexual networks. This review shows that disparities exist among the social determinants and that they are related to each other, as well as to core areas, sexual networks, and STD rates. Finally, we discuss the implications of our review for STD prevention and control with particular attention to STD program collaboration and service integration.

  7. Rapid diagnosis of sexually transmitted infections.

    Science.gov (United States)

    Otero-Guerra, Luis; Fernández-Blázquez, Ana; Vazquez, Fernando

    Sexually transmitted infections (STIs) are responsible for an enormous burden of morbidity and mortality. Worldwide, millions of cases of STIs, such as syphilis, chlamydia, or gonorrhoea occur every year, and there is now an increase in antimicrobial resistance in pathogens, such as gonococcus. Delay in diagnosis is one of the factors that justifies the difficulty in controlling these infections. Rapid diagnostic tests allow the introduction of aetiological treatment at the first visit, and also leads to treating symptomatic and asymptomatic patients more effectively, as well as to interrupt the epidemiological transmission chain without delay. The World Health Organisation includes these tests in its global strategy against STIs. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  8. Pattern of Sexually Transmitted Diseases in Chandigarh

    Directory of Open Access Journals (Sweden)

    Bhushan Kumar

    1987-01-01

    Full Text Available A retrospective,data analysis of sexually transmitted diseases was carried out to study the pattern of these diseases prevalent in the region. One thousand′five hundred and seventy,one patients′were seen from January 1977 to October 1985. Maks constituted 95.5% of this group and females the remaining 4.5%. Commonest age group affected was 20-29 years in both sexes. Condytoma acuminata was the commonest STD (21.40/o, followed by gonorrhoea (16.9%, chancroid (12.2% genital herpes (11.4%, syphilis (10.4%, not′specific ulcers (7.1%, donovanosis (6.3%,mixed infections (5.3% and NSU (4.1% Secondary syphilis was the most common (48.6% presentation of syphik and in women it od 75.8% of all the cases of syphilis. In′more than a quarter of patients, psycho- problems were the reason for attendance.

  9. [Anorectal manifestations of sexually transmitted infections].

    Science.gov (United States)

    Lautenschlager, Stephan

    2013-07-01

    The incidence of sexually transmitted infections is rising in Europe and in Switzerland since the beginning of the third millenium. Many organisms may affect the perianal skin and the anorectum. While some of these infections are a result of contigous spread from genital infection, most result from receptive anal intercourse affecting males who have sex with males but is seen increasingly in females as well since there is evidence of the increasing popularity of anal sex among heterosexuals. The symptoms of specific infections are largely dependent on the route and site of inoculation. Organisms that cause typical genital symptoms - such as syphilis, chancroid, herpes simplex or HPV-infection - result in similar symptoms when the perianal skin, the anoderm or the distal anal canal are the site of infection. Patients with proctitis may have unspecific signs in various degrees including mucous discharge, rectal bleeding, anorectal pain, superficial ulcers and sometimes generalized lymphadenopathy and fever. It is of utmost importance to include STIs (e. g. lymphogranuloma venereum, gonorrhea, non-LGV-chlamydia and herpes simplex) in the differential diagnosis in these patients. Unfortunately rectal infection with chlamydia and gonorrhea is asymptomatic in the majority of cases of men having sex with men and in high-risk females. A careful history and physical examination is essential in establishing a correct diagnosis, usually supported by proctoscopy, culture, PCR, serology and histology. Certain organisms, more commonly thought of as food- or water-borne disease may be sexually transmitted by direct or indirect fecal-oral contact from various sexual practices.

  10. Generalization of socially transmitted and instructed avoidance

    Directory of Open Access Journals (Sweden)

    Gemma eCameron

    2015-06-01

    Full Text Available Excessive avoidance behavior, in which an instrumental action prevents an upcoming aversive event, is a defining feature of anxiety disorders. Left unchecked, both fear and avoidance of potentially threatening stimuli may generalize to perceptually related stimuli and situations. The behavioral consequences of generalization mean that aversive learning experiences with specific threats may lead people to infer that classes of related stimuli are threatening, potentially dangerous, and need to be avoided, despite differences in physical form. Little is known about avoidance generalization in humans and the learning pathways by which it may be transmitted. In the present study, we compared two pathways to avoidance, instructions and social observation, on subsequent generalization of avoidance behavior, fear expectancy and physiological arousal. Participants first learned that one cue was a danger cue (conditioned stimulus, CS+ and another was a safety cue (CS-. Groups then were either instructed that a simple avoidance response in the presence of the CS+ cancelled upcoming shock presentations (instructed-learning group or observed a short movie showing a demonstrator performing the avoidance response to prevent shock (observational-learning group. During generalization testing, danger and safety cues were presented along with generalization stimuli that parametrically varied in perceptual similarity to the CS+. Reinstatement of fear and avoidance was also tested. Findings demonstrate, for the first time, generalization of socially transmitted and instructed avoidance: both groups showed comparable generalization gradients in fear expectancy, avoidance behavior and arousal. Return of fear was evident, suggesting that generalized avoidance remains persistent following extinction testing. The utility of the present paradigm for research on avoidance generalization is discussed.

  11. System for memorizing maximum values

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1992-08-01

    The invention discloses a system capable of memorizing maximum sensed values. The system includes conditioning circuitry which receives the analog output signal from a sensor transducer. The conditioning circuitry rectifies and filters the analog signal and provides an input signal to a digital driver, which may be either linear or logarithmic. The driver converts the analog signal to discrete digital values, which in turn triggers an output signal on one of a plurality of driver output lines n. The particular output lines selected is dependent on the converted digital value. A microfuse memory device connects across the driver output lines, with n segments. Each segment is associated with one driver output line, and includes a microfuse that is blown when a signal appears on the associated driver output line.

  12. Remarks on the maximum luminosity

    Science.gov (United States)

    Cardoso, Vitor; Ikeda, Taishi; Moore, Christopher J.; Yoo, Chul-Moon

    2018-04-01

    The quest for fundamental limitations on physical processes is old and venerable. Here, we investigate the maximum possible power, or luminosity, that any event can produce. We show, via full nonlinear simulations of Einstein's equations, that there exist initial conditions which give rise to arbitrarily large luminosities. However, the requirement that there is no past horizon in the spacetime seems to limit the luminosity to below the Planck value, LP=c5/G . Numerical relativity simulations of critical collapse yield the largest luminosities observed to date, ≈ 0.2 LP . We also present an analytic solution to the Einstein equations which seems to give an unboundedly large luminosity; this will guide future numerical efforts to investigate super-Planckian luminosities.

  13. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan

    2014-09-07

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  14. Maximum mutual information regularized classification

    KAUST Repository

    Wang, Jim Jing-Yan; Wang, Yi; Zhao, Shiguang; Gao, Xin

    2014-01-01

    In this paper, a novel pattern classification approach is proposed by regularizing the classifier learning to maximize mutual information between the classification response and the true class label. We argue that, with the learned classifier, the uncertainty of the true class label of a data sample should be reduced by knowing its classification response as much as possible. The reduced uncertainty is measured by the mutual information between the classification response and the true class label. To this end, when learning a linear classifier, we propose to maximize the mutual information between classification responses and true class labels of training samples, besides minimizing the classification error and reducing the classifier complexity. An objective function is constructed by modeling mutual information with entropy estimation, and it is optimized by a gradient descend method in an iterative algorithm. Experiments on two real world pattern classification problems show the significant improvements achieved by maximum mutual information regularization.

  15. Inflammasomes and Their Role in Innate Immunity of Sexually Transmitted Infections

    DEFF Research Database (Denmark)

    Verma, Vivek; Dhanda, Rakesh Singh; Møller, Niels Frimodt

    2016-01-01

    the mechanisms underlying pathogen-induced inflammasome activation is important if we are to develop novel therapeutic strategies to target sexually transmitted infections (STIs) related pathogens. This information is currently lacking in literature. In this review, we have discussed the role of various...

  16. Comparisons of receive array interference reduction techniques under erroneous generalized transmit beamforming

    KAUST Repository

    Radaydeh, Redha Mahmoud

    2014-02-01

    This paper studies generalized single-stream transmit beamforming employing receive array co-channel interference reduction algorithms under slow and flat fading multiuser wireless systems. The impact of imperfect prediction of channel state information for the desired user spatially uncorrelated transmit channels on the effectiveness of transmit beamforming for different interference reduction techniques is investigated. The case of over-loaded receive array with closely-spaced elements is considered, wherein it can be configured to specified interfering sources. Both dominant interference reduction and adaptive interference reduction techniques for statistically ordered and unordered interferers powers, respectively, are thoroughly studied. The effect of outdated statistical ordering of the interferers powers on the efficiency of dominant interference reduction is studied and then compared against the adaptive interference reduction. For the system models described above, new analytical formulations for the statistics of combined signal-to-interference-plus-noise ratio are presented, from which results for conventional maximum ratio transmission and single-antenna best transmit selection can be directly deduced as limiting cases. These results are then utilized to obtain quantitative measures for various performance metrics. They are also used to compare the achieved performance of various configuration models under consideration. © 1972-2012 IEEE.

  17. Power balance and loss mechanism analysis in RF transmit coil arrays.

    Science.gov (United States)

    Kuehne, Andre; Goluch, Sigrun; Waxmann, Patrick; Seifert, Frank; Ittermann, Bernd; Moser, Ewald; Laistler, Elmar

    2015-10-01

    To establish a framework for transmit array power balance calculations based on power correlation matrices to accurately quantify the loss contributions from different mechanisms such as coupling, lumped components, and radiation. Starting from Poynting's theorem, power correlation matrices are derived for all terms in the power balance, which is formulated as a matrix equation. Finite-difference time-domain simulations of two 7 T eight-channel head array coils at 297.2 MHz are used to verify the theoretical considerations and demonstrate their application. Care is taken to accurately incorporate all loss mechanisms. The power balance for static B1 phase shims as well as two-dimensional spatially selective transmit SENSE pulses is shown. The simulated power balance shows an excellent agreement with theory, with a maximum power imbalance of less than 0.11%. Power loss contributions from the different loss mechanisms vary significantly between the investigated setups, and depending on the excitation mode imposed on the coil. The presented approach enables a straightforward loss evaluation for an arbitrary excitation of transmit coil arrays. Worst-case power imbalance and losses are calculated in a straightforward manner. This allows for deeper insight into transmit array loss mechanisms, incorporation of radiated power components in specific absorption rate calculations and verification of electromagnetic simulations. © 2014 Wiley Periodicals, Inc.

  18. Determination of average conversion coefficients between kerma in air and H⁎(10) using primary and secondary X-ray beams and transmitted in the diagnostic radiology energy range

    International Nuclear Information System (INIS)

    Santos, Josilene C.; Gonzalez, Alejandro H.L.; Costa, Paulo R.

    2016-01-01

    Brazilian regulation establishes 1.14 Sv/Gy as unique conversion coefficient to convert air-kerma into the operational quantity ambient dose equivalent H⁎(10) disregarding its beam quality dependence. The present study computed mean conversion coefficients from primary, secondary and transmitted X-ray beams through barite mortar plates used in shielding of dedicated chest radiographic facilities in order to improve the current assessment of H⁎(10). To compute the mean conversion coefficients, the weighting of conversion coefficients corresponding to monoenergetic beams with the spectrum energy distribution in terms of air-kerma was considered. The maximum difference between the obtained conversion coefficients and the constant value recommended in national regulation is 53.4%. The conclusion based on these results is that a constant coefficient is not adequate for deriving the H⁎(10) from air-kerma measurements. (author)

  19. Transmit Power Optimisation in Wireless Network

    Directory of Open Access Journals (Sweden)

    Besnik Terziu

    2011-09-01

    Full Text Available Transmit power optimisation in wireless networks based on beamforming have emerged as a promising technique to enhance the spectrum efficiency of present and future wireless communication systems. The aim of this study is to minimise the access point power consumption in cellular networks while maintaining a targeted quality of service (QoS for the mobile terminals. In this study, the targeted quality of service is delivered to a mobile station by providing a desired level of Signal to Interference and Noise Ratio (SINR. Base-stations are coordinated across multiple cells in a multi-antenna beamforming system. This study focuses on a multi-cell multi-antenna downlink scenario where each mobile user is equipped with a single antenna, but where multiple mobile users may be active simultaneously in each cell and are separated via spatial multiplexing using beamforming. The design criteria is to minimize the total weighted transmitted power across the base-stations subject to SINR constraints at the mobile users. The main contribution of this study is to define an iterative algorithm that is capable of finding the joint optimal beamformers for all basestations, based on a correlation-based channel model, the full-correlation model. Among all correlated channel models, the correlated channel model used in this study is the most accurate, giving the best performance in terms of power consumption. The environment here in this study is chosen to be Non-Light of- Sight (NLOS condition, where a signal from a wireless transmitter passes several obstructions before arriving at a wireless receiver. Moreover there are many scatterers local to the mobile, and multiple reflections can occur among them before energy arrives at the mobile. The proposed algorithm is based on uplink-downlink duality using the Lagrangian duality theory. Time-Division Duplex (TDD is chosen as the platform for this study since it has been adopted to the latest technologies in Fourth

  20. Maximum entropy and Bayesian methods

    International Nuclear Information System (INIS)

    Smith, C.R.; Erickson, G.J.; Neudorfer, P.O.

    1992-01-01

    Bayesian probability theory and Maximum Entropy methods are at the core of a new view of scientific inference. These 'new' ideas, along with the revolution in computational methods afforded by modern computers allow astronomers, electrical engineers, image processors of any type, NMR chemists and physicists, and anyone at all who has to deal with incomplete and noisy data, to take advantage of methods that, in the past, have been applied only in some areas of theoretical physics. The title workshops have been the focus of a group of researchers from many different fields, and this diversity is evident in this book. There are tutorial and theoretical papers, and applications in a very wide variety of fields. Almost any instance of dealing with incomplete and noisy data can be usefully treated by these methods, and many areas of theoretical research are being enhanced by the thoughtful application of Bayes' theorem. Contributions contained in this volume present a state-of-the-art overview that will be influential and useful for many years to come

  1. Cooperative Spatial Reuse with Transmit Beamforming in Multi-rate Wireless Networks

    DEFF Research Database (Denmark)

    Lu, Chenguang; Fitzek, Frank; Eggers, Patrick Claus F.

    2009-01-01

    We present a cooperative spatial reuse (CSR) scheme as a cooperative extension of the current TDMA-based MAC to enable spatial reuse in multi-rate wireless networks. We model spatial reuse as a cooperation problem on utilizing the time slots obtained from the TDMA-based MAC. In CSR, there are two...... operation modes. One is TDMA mode while the other is spatial reuse mode in which links transmit simultaneously. Links contribute their own time slots to form a cooperative group to do spatial reuse. Each link joins the group only if it can benefit in capacity or energy efficiency. Otherwise, the link...... will leave spatial reuse mode and switch back to TDMA. In this work, we focus on the transmit beamforming techniques to enable CSR by interference cancellation on MISO (Multiple Input Single Output) links. We compare the CSR scheme using zero-forcing (ZF) transmit beamforming, namely ZF-CSR, to the TDMA...

  2. Inductive reasoning about causally transmitted properties.

    Science.gov (United States)

    Shafto, Patrick; Kemp, Charles; Bonawitz, Elizabeth Baraff; Coley, John D; Tenenbaum, Joshua B

    2008-11-01

    Different intuitive theories constrain and guide inferences in different contexts. Formalizing simple intuitive theories as probabilistic processes operating over structured representations, we present a new computational model of category-based induction about causally transmitted properties. A first experiment demonstrates undergraduates' context-sensitive use of taxonomic and food web knowledge to guide reasoning about causal transmission and shows good qualitative agreement between model predictions and human inferences. A second experiment demonstrates strong quantitative and qualitative fits to inferences about a more complex artificial food web. A third experiment investigates human reasoning about complex novel food webs where species have known taxonomic relations. Results demonstrate a double-dissociation between the predictions of our causal model and a related taxonomic model [Kemp, C., & Tenenbaum, J. B. (2003). Learning domain structures. In Proceedings of the 25th annual conference of the cognitive science society]: the causal model predicts human inferences about diseases but not genes, while the taxonomic model predicts human inferences about genes but not diseases. We contrast our framework with previous models of category-based induction and previous formal instantiations of intuitive theories, and outline challenges in developing a complete model of context-sensitive reasoning.

  3. Genital elephantiasis and sexually transmitted infections - revisited.

    Science.gov (United States)

    Gupta, Somesh; Ajith, C; Kanwar, Amrinder J; Sehgal, Virendra N; Kumar, Bhushan; Mete, Uttam

    2006-03-01

    Genital elephantiasis is an important medical problem in the tropics. It usually affects young and productive age group, and is associated with physical disability and extreme mental anguish. The majority of cases are due to filariasis; however, a small but significant proportion of patients develop genital elephantiasis due to bacterial sexually transmitted infections (STIs), mainly lymphogranuloma venereum (LGV) and donovanosis. STI-related genital elephantiasis should be differentiated from elephantiasis due to other causes, including filariasis, tuberculosis, haematological malignancies, iatrogenic, or dermatological diseases. Laboratory investigations like microscopy of tissue smear and nucleic acid amplification test for donovanosis, and serology and polymerase chain reaction for LGV may help in the diagnosis, but in endemic areas, in the absence of laboratory facilities, diagnosis largely depends on clinical characteristics. The causative agent of LGV, Chlamydia trachomatis serovar L1-L3, is a lymphotropic organism which leads to the development of thrombolymphangitis and perilymphangitis, and lymphadenitis. Long-standing oedema, fibrosis and lymphogranulomatous infiltration result in the final picture of elephantiasis. Elephantiasis in donovanosis is mainly due to constriction of the lymphatics which are trapped in the chronic granulomatous inflammatory response generated by the causative agent, Calymmatobacterium (Klebsiella) granulomatis. The LGV-associated genital elephantiasis should be treated with a prolonged course of doxycycline given orally, while donovanosis should be treated with azithromycin or trimethoprim-sulphamethoxazole combination given for a minimum of three weeks. Genital elephantiasis is not completely reversible with medical therapy alone and often needs to be reduced surgically.

  4. Maximum entropy principal for transportation

    International Nuclear Information System (INIS)

    Bilich, F.; Da Silva, R.

    2008-01-01

    In this work we deal with modeling of the transportation phenomenon for use in the transportation planning process and policy-impact studies. The model developed is based on the dependence concept, i.e., the notion that the probability of a trip starting at origin i is dependent on the probability of a trip ending at destination j given that the factors (such as travel time, cost, etc.) which affect travel between origin i and destination j assume some specific values. The derivation of the solution of the model employs the maximum entropy principle combining a priori multinomial distribution with a trip utility concept. This model is utilized to forecast trip distributions under a variety of policy changes and scenarios. The dependence coefficients are obtained from a regression equation where the functional form is derived based on conditional probability and perception of factors from experimental psychology. The dependence coefficients encode all the information that was previously encoded in the form of constraints. In addition, the dependence coefficients encode information that cannot be expressed in the form of constraints for practical reasons, namely, computational tractability. The equivalence between the standard formulation (i.e., objective function with constraints) and the dependence formulation (i.e., without constraints) is demonstrated. The parameters of the dependence-based trip-distribution model are estimated, and the model is also validated using commercial air travel data in the U.S. In addition, policy impact analyses (such as allowance of supersonic flights inside the U.S. and user surcharge at noise-impacted airports) on air travel are performed.

  5. Last Glacial Maximum Salinity Reconstruction

    Science.gov (United States)

    Homola, K.; Spivack, A. J.

    2016-12-01

    It has been previously demonstrated that salinity can be reconstructed from sediment porewater. The goal of our study is to reconstruct high precision salinity during the Last Glacial Maximum (LGM). Salinity is usually determined at high precision via conductivity, which requires a larger volume of water than can be extracted from a sediment core, or via chloride titration, which yields lower than ideal precision. It has been demonstrated for water column samples that high precision density measurements can be used to determine salinity at the precision of a conductivity measurement using the equation of state of seawater. However, water column seawater has a relatively constant composition, in contrast to porewater, where variations from standard seawater composition occur. These deviations, which affect the equation of state, must be corrected for through precise measurements of each ion's concentration and knowledge of apparent partial molar density in seawater. We have developed a density-based method for determining porewater salinity that requires only 5 mL of sample, achieving density precisions of 10-6 g/mL. We have applied this method to porewater samples extracted from long cores collected along a N-S transect across the western North Atlantic (R/V Knorr cruise KN223). Density was determined to a precision of 2.3x10-6 g/mL, which translates to salinity uncertainty of 0.002 gms/kg if the effect of differences in composition is well constrained. Concentrations of anions (Cl-, and SO4-2) and cations (Na+, Mg+, Ca+2, and K+) were measured. To correct salinities at the precision required to unravel LGM Meridional Overturning Circulation, our ion precisions must be better than 0.1% for SO4-/Cl- and Mg+/Na+, and 0.4% for Ca+/Na+, and K+/Na+. Alkalinity, pH and Dissolved Inorganic Carbon of the porewater were determined to precisions better than 4% when ratioed to Cl-, and used to calculate HCO3-, and CO3-2. Apparent partial molar densities in seawater were

  6. Maximum Parsimony on Phylogenetic networks

    Science.gov (United States)

    2012-01-01

    Background Phylogenetic networks are generalizations of phylogenetic trees, that are used to model evolutionary events in various contexts. Several different methods and criteria have been introduced for reconstructing phylogenetic trees. Maximum Parsimony is a character-based approach that infers a phylogenetic tree by minimizing the total number of evolutionary steps required to explain a given set of data assigned on the leaves. Exact solutions for optimizing parsimony scores on phylogenetic trees have been introduced in the past. Results In this paper, we define the parsimony score on networks as the sum of the substitution costs along all the edges of the network; and show that certain well-known algorithms that calculate the optimum parsimony score on trees, such as Sankoff and Fitch algorithms extend naturally for networks, barring conflicting assignments at the reticulate vertices. We provide heuristics for finding the optimum parsimony scores on networks. Our algorithms can be applied for any cost matrix that may contain unequal substitution costs of transforming between different characters along different edges of the network. We analyzed this for experimental data on 10 leaves or fewer with at most 2 reticulations and found that for almost all networks, the bounds returned by the heuristics matched with the exhaustively determined optimum parsimony scores. Conclusion The parsimony score we define here does not directly reflect the cost of the best tree in the network that displays the evolution of the character. However, when searching for the most parsimonious network that describes a collection of characters, it becomes necessary to add additional cost considerations to prefer simpler structures, such as trees over networks. The parsimony score on a network that we describe here takes into account the substitution costs along the additional edges incident on each reticulate vertex, in addition to the substitution costs along the other edges which are

  7. Incidence of sexually transmitted infections during pregnancy.

    Directory of Open Access Journals (Sweden)

    Chloe A Teasdale

    Full Text Available Prevalence of sexually transmitted infections (STI is high among pregnant women in certain settings. We estimated STI incidence and compared STI risk in pregnant and non-pregnant women. Data came from the Methods for Improving Reproductive Health in Africa (MIRA study conducted in South Africa and Zimbabwe 2003-2006. Women aged 18-50 years with at least one follow-up visit within 6 months of enrollment were included. Follow-up visits included laboratory testing for pregnancy, chlamydia, gonorrhea, trichomoniasis, and HIV, as well as self-report of hormonal contraceptive (HC use, sexual behaviors and intravaginal practices. All visits were classified according to pregnancy status. Incidence of each STI was calculated using follow-up time. Cox proportional hazards models were fitted using pregnancy as a time-varying exposure and sexual behaviors and intravaginal practices as time-varying covariates. Among 4,549 women, 766 (16.8% had a positive pregnancy test. Median follow-up time was 18 months [IQR: 12-24]. The overall incidence rate of chlamydia was 6.7 per 100 person years (py and 9.9/100py during pregnancy; gonorrhea incidence was 2.7/100py and 4.9/100py during pregnancy; trichomoniasis incidence was 7.1/100py overall and 9.2/100py during pregnancy. Overall HIV incidence was 3.9/100py and 3.8/100py during pregnancy. In crude models, pregnancy increased risk for chlamydia (hazard ratio (HR 1.5, 95%CI: 1.1-1.2, however there was no increased risk of any measured STI in adjusted models. STI Incidence was high during pregnancy however pregnancy did not increase STI risk after adjustment for sexual behaviors. Greater efforts are needed to help pregnant women avoid STIs.

  8. Sexually transmitted infections in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Madani Tariq A

    2006-01-01

    Full Text Available Abstract Background Data on sexually transmitted infections (STIs in Saudi Arabia (SA and other Islamic countries are limited. This study describes the results of a five-year surveillance for STIs in SA. Methods This is a case series descriptive study of all confirmed STIs diagnosed in SA from January, 1995 through December, 1999. Results A total of 39049 STIs were reported to the Ministry of Health. Reported STIs included nongonococcal urethritis (14557 infections, 37.3%, trichomoniasis (10967 infections, 28.1%, gonococcal urethritis (5547 infections, 14.2%, syphilis (3385 infections, 8.7%, human immunodeficiency virus (2917 infections, 7.5%, genital warts (1382, 3.5%, genital herpes (216 infections, 0.6%, and chancroid (78 infections, 0.2%. The average annual incidence of STIs per 100,000 population for Saudis and non-Saudis, respectively, was as follows: 14.8 and 7.5 for nongonococcal urethritis, 9.4 and 10.4 for trichomoniasis, 5.2 and 4.2 for gonorrhea, 1.7 and 6.4 for syphilis, 0.6 and 8.0 for HIV, 1.4 and 0.7 for genital warts, 0.1 and 0.4 for genital herpes, and 0.1 and 0.1 for chancroid. The incidence of STIs was somewhat steady over the surveillance period except for nongonococcal urethritis which gradually increased. Conclusion Nongonococcal urethritis, trichomoniasis, and gonococcal urethritis were the most commonly reported STIs in SA. Even though the incidence of STIs in SA is limited, appropriate preventive strategies that conform to the Islamic rules and values are essential and should be of highest priority for policymakers because of the potential of such infections to spread particularly among the youth.

  9. Note on transmitted complexity for quantum dynamical systems

    Science.gov (United States)

    Watanabe, Noboru; Muto, Masahiro

    2017-10-01

    Transmitted complexity (mutual entropy) is one of the important measures for quantum information theory developed recently in several ways. We will review the fundamental concepts of the Kossakowski, Ohya and Watanabe entropy and define a transmitted complexity for quantum dynamical systems. This article is part of the themed issue `Second quantum revolution: foundational questions'.

  10. 47 CFR 25.271 - Control of transmitting stations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Control of transmitting stations. 25.271 Section 25.271 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.271 Control of transmitting stations. (a) The licensee of...

  11. GNSS satellite transmit power and its impact on orbit determination

    Science.gov (United States)

    Steigenberger, Peter; Thoelert, Steffen; Montenbruck, Oliver

    2018-06-01

    Antenna thrust is a small acceleration acting on Global Navigation Satellite System satellites caused by the transmission of radio navigation signals. Knowledge about the transmit power and the mass of the satellites is required for the computation of this effect. The actual transmit power can be obtained from measurements with a high-gain antenna and knowledge about the properties of the transmit and receive antennas as well as losses along the propagation path. Transmit power measurements for different types of GPS, GLONASS, Galileo, and BeiDou-2 satellites were taken with a 30-m dish antenna of the German Aerospace Center (DLR) located at its ground station in Weilheim. For GPS, total L-band transmit power levels of 50-240 W were obtained, 20-135 W for GLONASS, 95-265 W for Galileo, and 130-185 W for BeiDou-2. The transmit power differs usually only slightly for individual spacecraft within one satellite block. An exception are the GLONASS-M satellites where six subgroups with different transmit power levels could be identified. Considering the antenna thrust in precise orbit determination of GNSS satellites decreases the orbital radius by 1-27 mm depending on the transmit power, the satellite mass, and the orbital period.

  12. Discourse on the values transmitted in universities Uganda ...

    African Journals Online (AJOL)

    The study delved into the values transmitted in Universities in Uganda. Data were collected from a sample of 850 respondents who were drawn from faith-based, for–profit and public universities in the country. It was found that material, social/ public, personal and religious values are transmitted to students in the selected ...

  13. 22 CFR 1203.735-214 - Transmitting communications and gifts.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Transmitting communications and gifts. 1203.735....735-214 Transmitting communications and gifts. (a) Correspondence. In corresponding with anyone other... it to be clearly in the public interest to do so. (c) Gifts. An employee shall not act as an agent...

  14. Two-dimensional maximum entropy image restoration

    International Nuclear Information System (INIS)

    Brolley, J.E.; Lazarus, R.B.; Suydam, B.R.; Trussell, H.J.

    1977-07-01

    An optical check problem was constructed to test P LOG P maximum entropy restoration of an extremely distorted image. Useful recovery of the original image was obtained. Comparison with maximum a posteriori restoration is made. 7 figures

  15. Genital Herpes: Insights into Sexually Transmitted Infectious Disease.

    Science.gov (United States)

    Jaishankar, Dinesh; Shukla, Deepak

    2016-06-27

    Etiology, transmission and protection: Herpes simplex virus-2 (HSV-2) is a leading cause of sexually transmitted infections with recurring manifestations throughout the lifetime of infected hosts. Currently no effective vaccines or prophylactics exist that provide complete protection or immunity from the virus, which is endemic throughout the world. Pathology/Symptomatology: Primary and recurrent infections result in lesions and inflammation around the genital area and the latter accounts for majority of genital herpes instances. Immunocompromised patients including neonates are susceptible to additional systemic infections including debilitating consequences of nervous system inflammation. Epidemiology, incidence and prevalence: More than 500 million people are infected worldwide and most reported cases involve the age groups between 16-40 years, which coincides with an increase in sexual activity among this age group. While these numbers are an estimate, the actual numbers may be underestimated as many people are asymptomatic or do not report the symptoms. Treatment and curability: Currently prescribed medications, mostly nucleoside analogs, only reduce the symptoms caused by an active infection, but do not eliminate the virus or reduce latency. Therefore, no cure exists against genital herpes and infected patients suffer from periodic recurrences of disease symptoms for their entire lives. Molecular mechanisms of infection: The last few decades have generated many new advances in our understanding of the mechanisms that drive HSV infection. The viral entry receptors such as nectin-1 and HVEM have been identified, cytoskeletal signaling and membrane structures such as filopodia have been directly implicated in viral entry, host motor proteins and their viral ligands have been shown to facilitate capsid transport and many host and HSV proteins have been identified that help with viral replication and pathogenesis. New understanding has emerged on the role of

  16. Genital Herpes: Insights into Sexually Transmitted Infectious Disease

    Science.gov (United States)

    Jaishankar, Dinesh; Shukla, Deepak

    2016-01-01

    Etiology, transmission and protection: Herpes simplex virus-2 (HSV-2) is a leading cause of sexually transmitted infections with recurring manifestations throughout the lifetime of infected hosts. Currently no effective vaccines or prophylactics exist that provide complete protection or immunity from the virus, which is endemic throughout the world. Pathology/Symptomatology: Primary and recurrent infections result in lesions and inflammation around the genital area and the latter accounts for majority of genital herpes instances. Immunocompromised patients including neonates are susceptible to additional systemic infections including debilitating consequences of nervous system inflammation. Epidemiology, incidence and prevalence: More than 500 million people are infected worldwide and most reported cases involve the age groups between 16-40 years, which coincides with an increase in sexual activity among this age group. While these numbers are an estimate, the actual numbers may be underestimated as many people are asymptomatic or do not report the symptoms. Treatment and curability: Currently prescribed medications, mostly nucleoside analogs, only reduce the symptoms caused by an active infection, but do not eliminate the virus or reduce latency. Therefore, no cure exists against genital herpes and infected patients suffer from periodic recurrences of disease symptoms for their entire lives. Molecular mechanisms of infection: The last few decades have generated many new advances in our understanding of the mechanisms that drive HSV infection. The viral entry receptors such as nectin-1 and HVEM have been identified, cytoskeletal signaling and membrane structures such as filopodia have been directly implicated in viral entry, host motor proteins and their viral ligands have been shown to facilitate capsid transport and many host and HSV proteins have been identified that help with viral replication and pathogenesis. New understanding has emerged on the role of

  17. Receiver function estimated by maximum entropy deconvolution

    Institute of Scientific and Technical Information of China (English)

    吴庆举; 田小波; 张乃铃; 李卫平; 曾融生

    2003-01-01

    Maximum entropy deconvolution is presented to estimate receiver function, with the maximum entropy as the rule to determine auto-correlation and cross-correlation functions. The Toeplitz equation and Levinson algorithm are used to calculate the iterative formula of error-predicting filter, and receiver function is then estimated. During extrapolation, reflective coefficient is always less than 1, which keeps maximum entropy deconvolution stable. The maximum entropy of the data outside window increases the resolution of receiver function. Both synthetic and real seismograms show that maximum entropy deconvolution is an effective method to measure receiver function in time-domain.

  18. Sexually transmitted diseases among psychiatric patients in Brazil.

    Science.gov (United States)

    Dutra, Maria Rita Teixeira; Campos, Lorenza Nogueira; Guimarães, Mark Drew Crosland

    2014-01-01

    Sexually transmitted diseases are still highly prevalent worldwide and represent an important public health problem. Psychiatric patients are at increased risk of sexually transmitted diseases but there are scarce published studies with representative data of this population. We sought to estimate the prevalence and correlates of self-reported sexually transmitted diseases among patients with mental illnesses under care in a national representative sample in Brazil (n=2145). More than one quarter of the sample (25.8%) reported a lifetime history of sexually transmitted disease. Multivariate analyses showed that patients with a lifetime sexually transmitted disease history were older, had history of homelessness, used more alcohol and illicit drugs, suffered violence, perceived themselves to be at greater risk for HIV and had high risk sexual behavioral: practised unprotected sex, started sexual life earlier, had more than ten sexual partners, exchanged money and/or drugs for sex and had a partner that refused to use condom. Our findings indicate a high prevalence of self-reported sexually transmitted diseases among psychiatric patients in Brazil, and emphasize the need for implementing sexually transmitted diseases prevention programs in psychiatric settings, including screening, treatment, and behavioral modification interventions. Copyright © 2013 Elsevier Editora Ltda. All rights reserved.

  19. Can blood tranfusion transmit cancer? A literature review.

    Science.gov (United States)

    Yang, Hung; Lee, June; Seed, Clive R; Keller, Anthony J

    2010-07-01

    Blood services around the world face increasing challenges in recruiting voluntary blood donors. With increasing donor restrictions and ageing populations, it is essential to look for any existing restrictions that may be relaxed in the light of currently available evidence. We propose that one such restriction is the exclusion of blood donors with a history of a malignancy. Most blood services apart from the United States and Australia continue the historical precaution of permanently excluding donors with a history of cancer, despite the absence of any convincing reports of cancer transmission among the millions of allogeneic blood transfusions performed since the advent of blood banking. In 2007, workers in Scandinavia published convincing data from the SCANDAT (Scandinavian Donations and Transfusions) database that showed no increase in cancer risk among recipients of blood from "precancerous" donors (ie, donors who were later diagnosed with cancer within 5 years of donating) vs recipients of blood from other donors. This review aims to reconcile this finding with other data available in the published literature that is pertinent to the risk of transmitting cancer via blood transfusion, with a view to establishing that there is now sufficient evidence to support the acceptance of carefully selected blood donors with a history of malignant disease. Copyright 2010 Elsevier Inc. All rights reserved.

  20. SVD-BASED TRANSMIT BEAMFORMING FOR VARIOUS MODULATIONS WITH CONVOLUTION ENCODING

    Directory of Open Access Journals (Sweden)

    M. Raja

    2011-09-01

    Full Text Available This paper present a new beamforming technique using singular value decomposition (SVD for closed loop Multiple-input, multiple-output (MIMO wireless systems with various modulation techniques such as BPSK, 16-QAM, 16-PSK, DPSK and PAM along with convolution encoder. The channel matrix is decomposed into a number of independent orthogonal modes of excitation, which refer to as eigenmodes of the channel. Transmit precoding is performed by multiplying the input symbols with unitary matrix to produce the transmit beamforming, and the precoded symbols are transmitted over Rayleigh fading channel. At the receiver, combining process is performed by using maximum ratio combiner (MRC, and the receiver shaping is performed to retrieve the original input symbols by multiplying the received signal with conjugate transpose of the unitary matrix. Furthermore, the expressions for average bit error rate (BER for M-PSK and average BER for M-QAM are derived. The superiority of the proposed work is proved by simulation results and the proposed work is compared to the other beamforming methods.

  1. Analysis of Ultrasonic Transmitted Signal for Apple using Wavelet Transform

    International Nuclear Information System (INIS)

    Kim, Ki Bok; Lee, Sang Dae; Choi, Man Yong; Kim, Man Soo

    2005-01-01

    This study was conducted to analyze the ultrasonic transmitted signal for apple using wavelet transform. Fruit consists of nonlinear visco-elastic properties such as flesh, an ovary and rind and lienee most ultrasonic wave is attenuated and its frequency is shifted during passing the fruit. Thus it is not easy to evaluate the internal quality of the fruit using typical ultrasonic parameters such as wave velocity, attenuation, and frequency spectrum. The discrete wavelet transform was applied to the ultrasonic transmitted signal for apple. The magnitude of the first peak frequency of the wavelet basis from the ultrasonic transmitted signal showed a close correlation to the storage time of apple

  2. Beat the Deviations in Estimating Maximum Power of Thermoelectric Modules

    DEFF Research Database (Denmark)

    Gao, Junling; Chen, Min

    2013-01-01

    Under a certain temperature difference, the maximum power of a thermoelectric module can be estimated by the open-circuit voltage and the short-circuit current. In practical measurement, there exist two switch modes, either from open to short or from short to open, but the two modes can give...... different estimations on the maximum power. Using TEG-127-2.8-3.5-250 and TEG-127-1.4-1.6-250 as two examples, the difference is about 10%, leading to some deviations with the temperature change. This paper analyzes such differences by means of a nonlinear numerical model of thermoelectricity, and finds out...... that the main cause is the influence of various currents on the produced electromotive potential. A simple and effective calibration method is proposed to minimize the deviations in specifying the maximum power. Experimental results validate the method with improved estimation accuracy....

  3. Partner notification of sexually transmitted diseases: practices and preferences.

    Science.gov (United States)

    Gursahaney, Priya R; Jeong, Kwonho; Dixon, Bruce W; Wiesenfeld, Harold C

    2011-09-01

    Timely notification and treatment of sex partners exposed to a sexually transmitted disease (STD) is essential to reduce reinfection and transmission. Our objectives were to determine factors associated with patient-initiated notification of sex partners and preferences regarding standard partner referral versus expedited partner therapy (EPT). Participants diagnosed with gonorrhea, chlamydia, trichomoniasis, or nongonococcal urethritis within the previous year were administered a baseline survey asking about demographics, sexual history, and partner treatment preferences (standard partner referral vs. EPT). They identified up to 4 sex partners within the past 2 months, and answered questions on relationship characteristics, quality, and notification self-efficacy. At follow-up, participants with a current STD were asked whether they notified their partners. Generalized estimating equations were used to evaluate the associations between predictor variables and partner notification. Of the 201 subjects enrolled, 157 had a current STD diagnosis, and 289 sex partners were identified. The rate of successful partner notification was 77.3% (157/203 sex partners). Partner notification was increased if the subject had a long-term relationship with a sex partner (odds ratio: 3.07; 95% confidence interval: 1.43, 6.58), considered the partner to be a main partner (odds ratio: 2.53; 95% confidence interval: 1.43, 6.58), or had increased notification self-efficacy. Overall, participants did not prefer EPT over standard referral; however, females, those with higher education levels, and those with a prior STD preferred EPT. Patient-initiated partner referral is more successful in patients with increased self-efficacy who have stronger interpersonal relationships with their sex partners.

  4. 5 CFR 531.221 - Maximum payable rate rule.

    Science.gov (United States)

    2010-01-01

    ... before the reassignment. (ii) If the rate resulting from the geographic conversion under paragraph (c)(2... previous rate (i.e., the former special rate after the geographic conversion) with the rates on the current... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Maximum payable rate rule. 531.221...

  5. SIMULATION OF NEW SIMPLE FUZZY LOGIC MAXIMUM POWER ...

    African Journals Online (AJOL)

    2010-06-30

    Jun 30, 2010 ... Basic structure photovoltaic system Solar array mathematic ... The equivalent circuit model of a solar cell consists of a current generator and a diode .... control of boost converter (tracker) such that maximum power is achieved at the output of the solar panel. Fig.11. The membership function of input. Fig.12.

  6. Heat Convection at the Density Maximum Point of Water

    Science.gov (United States)

    Balta, Nuri; Korganci, Nuri

    2018-01-01

    Water exhibits a maximum in density at normal pressure at around 4° degree temperature. This paper demonstrates that during cooling, at around 4 °C, the temperature remains constant for a while because of heat exchange associated with convective currents inside the water. Superficial approach implies it as a new anomaly of water, but actually it…

  7. Measurement of scattered and transmitted X-rays from intra-oral and panoramic dental X-ray equipment.

    Science.gov (United States)

    Holroyd, John Richard

    2018-04-10

    To quantify the levels of transmitted radiation arising from the use of intra-oral dental X-ray equipment and scattered radiation arising from the use of both intra-oral and panoramic X-ray equipment. Methods: Levels of scattered radiation were measured at 1 m from a phantom, using an 1800 cc ion chamber. Transmitted radiation was measured using both: i) a phantom and Dose Area Product (DAP) meter, ii) a patient and an 1800 cc ion chamber. Results: For intra-oral radiography the patient study gave a maximum transmission of 1.80% (range 0.04% to 1.80%, mean 0.26%) and the phantom study gave a maximum transmission of 6% (range 2% to 6%, mean 5%). The maximum scattered radiation, per unit DAP, was 5.5 nGy (mGy cm2)-1 at 70 kVp and a distance of 1 m. For panoramic radiography the maximum scattered radiation was 9.3 nGy (mGy cm2)-1 at 80 kVp and a distance of 1 m. Conclusions: Typical doses from scattered and transmitted radiation in modern dental practice have been measured and values are presented to enable the calculation of adequate protection measures for dental radiography rooms. Advances in knowledge: Previous studies have used a phantom and measured radiation doses at 1 m from the phantom to determine the radiation dose transmitted through a patient, whereas this study uses both patient and phantom measurements together with a large area dose meter, positioned to capture the entire X-ray beam, to ensure more realistic dose measurements can be made. © 2018 IOP Publishing Ltd.

  8. Switch and examine transmit diversity for spectrum sharing systems

    KAUST Repository

    Abdallah, Mohamed M.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

    2011-01-01

    In this paper, we develop a switch and examine transmit diversity algorithm for spectrum sharing cognitive networks. We consider a cognitive network composed of a primary link that employs constant rate and constant power transmission scheme

  9. Adaptive single-antenna transmit selection with interference suppression

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh; Alouini, Mohamed-Slim

    2011-01-01

    -efficient transmission with as low transmit channel estimations as possible. Due to the fact that the number of active co-channel interfering signals and their corresponding powers experience random behavior, the adaptation to channels conditions, assuming uniform buffer

  10. Behavioural risk factors for sexually transmitted infections and health ...

    African Journals Online (AJOL)

    Behavioural risk factors for sexually transmitted infections and health ... sharing of personal effects, malnourishment and sexual harassment. ... Development of risk reduction and appropriate sexual health interventions targeted at prevention ...

  11. Pair formation models for sexually transmitted infections : A primer

    NARCIS (Netherlands)

    Kretzschmar, MEE; Heijne, Janneke C M

    For modelling sexually transmitted infections, duration of partnerships can strongly influence the transmission dynamics of the infection. If partnerships are monogamous, pairs of susceptible individuals are protected from becoming infected, while pairs of infected individuals delay onward

  12. Alfalfa Leaf Curl Virus: an Aphid-Transmitted Geminivirus.

    Science.gov (United States)

    Roumagnac, Philippe; Granier, Martine; Bernardo, Pauline; Deshoux, Maëlle; Ferdinand, Romain; Galzi, Serge; Fernandez, Emmanuel; Julian, Charlotte; Abt, Isabelle; Filloux, Denis; Mesléard, François; Varsani, Arvind; Blanc, Stéphane; Martin, Darren P; Peterschmitt, Michel

    2015-09-01

    The family Geminiviridae comprises seven genera differentiated by genome organization, sequence similarity, and insect vector. Capulavirus, an eighth genus, has been proposed to accommodate two newly discovered highly divergent geminiviruses that presently have no known vector. Alfalfa leaf curl virus, identified here as a third capulavirus, is shown to be transmitted by Aphis craccivora. This is the first report of an aphid-transmitted geminivirus. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. EXPERIMENTAL STUDY ON LIGHT TRANSMITTING CONCRETE BY USING OPTICAL FIBRE

    OpenAIRE

    S. Suganya; S. Minu Gopika

    2017-01-01

    Light transmitting concrete is one of the fibre reinforced concrete which is mainly used for aesthetic application by incorporating the optical fibres in concrete. Optical fibres help to transmit the light through the fibres and the end-light type of fibre is used to increase the aesthetic appearance of the concrete which is like a transparent concrete. Fibres are arranged in different layers, to increase the load carrying capacity and also the pattern can be created to make the concrete deco...

  14. Secure direct communication based on secret transmitting order of particles

    International Nuclear Information System (INIS)

    Zhu Aidong; Zhang Shou; Xia Yan; Fan Qiubo

    2006-01-01

    We propose the schemes of quantum secure direct communication based on a secret transmitting order of particles. In these protocols, the secret transmitting order of particles ensures the security of communication, and no secret messages are leaked even if the communication is interrupted for security. This strategy of security for communication is also generalized to a quantum dialogue. It not only ensures the unconditional security but also improves the efficiency of communication

  15. Some Models for Epidemics of Vector-Transmitted Diseases

    OpenAIRE

    Brauer, Fred; Castillo-Chavez, Carlos; Mubayi, Anuj; Towers, Sherry

    2016-01-01

    Vector-transmitted diseases such as dengue fever and chikungunya have been spreading rapidly in many parts of the world. The Zika virus has been known since 1947 and invaded South America in 2013. It can be transmitted not only by (mosquito) vectors but also directly through sexual contact. Zika has developed into a serious global health problem because, while most cases are asymptomatic or very light, babies born to Zika - infected mothers may develop microcephaly and other very serious birt...

  16. Maximum power point tracker based on fuzzy logic

    International Nuclear Information System (INIS)

    Daoud, A.; Midoun, A.

    2006-01-01

    The solar energy is used as power source in photovoltaic power systems and the need for an intelligent power management system is important to obtain the maximum power from the limited solar panels. With the changing of the sun illumination due to variation of angle of incidence of sun radiation and of the temperature of the panels, Maximum Power Point Tracker (MPPT) enables optimization of solar power generation. The MPPT is a sub-system designed to extract the maximum power from a power source. In the case of solar panels power source. the maximum power point varies as a result of changes in its electrical characteristics which in turn are functions of radiation dose, temperature, ageing and other effects. The MPPT maximum the power output from panels for a given set of conditions by detecting the best working point of the power characteristic and then controls the current through the panels or the voltage across them. Many MPPT methods have been reported in literature. These techniques of MPPT can be classified into three main categories that include: lookup table methods, hill climbing methods and computational methods. The techniques vary according to the degree of sophistication, processing time and memory requirements. The perturbation and observation algorithm (hill climbing technique) is commonly used due to its ease of implementation, and relative tracking efficiency. However, it has been shown that when the insolation changes rapidly, the perturbation and observation method is slow to track the maximum power point. In recent years, the fuzzy controllers are used for maximum power point tracking. This method only requires the linguistic control rules for maximum power point, the mathematical model is not required and therefore the implementation of this control method is easy to real control system. In this paper, we we present a simple robust MPPT using fuzzy set theory where the hardware consists of the microchip's microcontroller unit control card and

  17. Revealing the Maximum Strength in Nanotwinned Copper

    DEFF Research Database (Denmark)

    Lu, L.; Chen, X.; Huang, Xiaoxu

    2009-01-01

    boundary–related processes. We investigated the maximum strength of nanotwinned copper samples with different twin thicknesses. We found that the strength increases with decreasing twin thickness, reaching a maximum at 15 nanometers, followed by a softening at smaller values that is accompanied by enhanced...

  18. Maximum field capability of energy saver superconducting magnets

    International Nuclear Information System (INIS)

    Turkot, F.; Cooper, W.E.; Hanft, R.; McInturff, A.

    1983-01-01

    At an energy of 1 TeV the superconducting cable in the Energy Saver dipole magnets will be operating at ca. 96% of its nominal short sample limit; the corresponding number in the quadrupole magnets will be 81%. All magnets for the Saver are individually tested for maximum current capability under two modes of operation; some 900 dipoles and 275 quadrupoles have now been measured. The dipole winding is composed of four individually wound coils which in general come from four different reels of cable. As part of the magnet fabrication quality control a short piece of cable from both ends of each reel has its critical current measured at 5T and 4.3K. In this paper the authors describe and present the statistical results of the maximum field tests (including quench and cycle) on Saver dipole and quadrupole magnets and explore the correlation of these tests with cable critical current

  19. Maximum Safety Regenerative Power Tracking for DC Traction Power Systems

    Directory of Open Access Journals (Sweden)

    Guifu Du

    2017-02-01

    Full Text Available Direct current (DC traction power systems are widely used in metro transport systems, with running rails usually being used as return conductors. When traction current flows through the running rails, a potential voltage known as “rail potential” is generated between the rails and ground. Currently, abnormal rises of rail potential exist in many railway lines during the operation of railway systems. Excessively high rail potentials pose a threat to human life and to devices connected to the rails. In this paper, the effect of regenerative power distribution on rail potential is analyzed. Maximum safety regenerative power tracking is proposed for the control of maximum absolute rail potential and energy consumption during the operation of DC traction power systems. The dwell time of multiple trains at each station and the trigger voltage of the regenerative energy absorbing device (READ are optimized based on an improved particle swarm optimization (PSO algorithm to manage the distribution of regenerative power. In this way, the maximum absolute rail potential and energy consumption of DC traction power systems can be reduced. The operation data of Guangzhou Metro Line 2 are used in the simulations, and the results show that the scheme can reduce the maximum absolute rail potential and energy consumption effectively and guarantee the safety in energy saving of DC traction power systems.

  20. Mycoplasma genitalium: An Emerging Sexually Transmitted Infection

    Directory of Open Access Journals (Sweden)

    Jessian L. Munoz

    2016-01-01

    Full Text Available Mycoplasma genitalium has been recognized as a cause of male urethritis, and there is now evidence suggesting that it causes cervicitis and pelvic inflammatory disease in women. M. genitalium is a slow growing organism, and, with the advent of nucleic acid amplification test (NAAT, more studies are being performed, and knowledge about the pathogenicity of this organism elucidated. With NAAT detection, treatment modalities have been studied, and the next challenge is to determine the most effective antimicrobial therapy. Doxycycline, the first-line antibiotic for urethritis, is largely ineffective in the treatment of M. genitalium and furthermore, resistance to macrolide has also emerged. The most effective drug is Moxifloxacin although there are emerging reports of resistance to it in various parts of the world. This paper not only highlights the current research and knowledge, but also reviews the diversity of health implications on the health of men and women infected with M. genitalium. Alternate antibiotics and the impact of M. genitalium on infertility are areas that require more studies as we continue to research into this microorganism.

  1. Sexually transmitted infections among HIV-1-discordant couples.

    Directory of Open Access Journals (Sweden)

    Brandon L Guthrie

    2009-12-01

    Full Text Available More new HIV-1 infections occur within stable HIV-1-discordant couples than in any other group in Africa, and sexually transmitted infections (STIs may increase transmission risk among discordant couples, accounting for a large proportion of new HIV-1 infections. Understanding correlates of STIs among discordant couples will aid in optimizing interventions to prevent HIV-1 transmission in these couples.HIV-1-discordant couples in which HIV-1-infected partners were HSV-2-seropositive were tested for syphilis, chlamydia, gonorrhea, and trichomoniasis, and HIV-1-uninfected partners were tested for HSV-2. We assessed sociodemographic, behavioral, and biological correlates of a current STI.Of 416 couples enrolled, 16% were affected by a treatable STI, and among these both partners were infected in 17% of couples. A treatable STI was found in 46 (11% females and 30 (7% males. The most prevalent infections were trichomoniasis (5.9% and syphilis (2.6%. Participants were 5.9-fold more likely to have an STI if their partner had an STI (P<0.01, and STIs were more common among those reporting any unprotected sex (OR = 2.43; P<0.01 and those with low education (OR = 3.00; P<0.01. Among HIV-1-uninfected participants with an HSV-2-seropositive partner, females were significantly more likely to be HSV-2-seropositive than males (78% versus 50%, P<0.01.Treatable STIs were common among HIV-1-discordant couples and the majority of couples affected by an STI were discordant for the STI, with relatively high HSV-2 discordance. Awareness of STI correlates and treatment of both partners may reduce HIV-1 transmission.ClinicalTrials.gov NCT00194519.

  2. A maximum likelihood framework for protein design

    Directory of Open Access Journals (Sweden)

    Philippe Hervé

    2006-06-01

    Full Text Available Abstract Background The aim of protein design is to predict amino-acid sequences compatible with a given target structure. Traditionally envisioned as a purely thermodynamic question, this problem can also be understood in a wider context, where additional constraints are captured by learning the sequence patterns displayed by natural proteins of known conformation. In this latter perspective, however, we still need a theoretical formalization of the question, leading to general and efficient learning methods, and allowing for the selection of fast and accurate objective functions quantifying sequence/structure compatibility. Results We propose a formulation of the protein design problem in terms of model-based statistical inference. Our framework uses the maximum likelihood principle to optimize the unknown parameters of a statistical potential, which we call an inverse potential to contrast with classical potentials used for structure prediction. We propose an implementation based on Markov chain Monte Carlo, in which the likelihood is maximized by gradient descent and is numerically estimated by thermodynamic integration. The fit of the models is evaluated by cross-validation. We apply this to a simple pairwise contact potential, supplemented with a solvent-accessibility term, and show that the resulting models have a better predictive power than currently available pairwise potentials. Furthermore, the model comparison method presented here allows one to measure the relative contribution of each component of the potential, and to choose the optimal number of accessibility classes, which turns out to be much higher than classically considered. Conclusion Altogether, this reformulation makes it possible to test a wide diversity of models, using different forms of potentials, or accounting for other factors than just the constraint of thermodynamic stability. Ultimately, such model-based statistical analyses may help to understand the forces

  3. Mass mortality of the vermetid gastropod Ceraesignum maximum

    Science.gov (United States)

    Brown, A. L.; Frazer, T. K.; Shima, J. S.; Osenberg, C. W.

    2016-09-01

    Ceraesignum maximum (G.B. Sowerby I, 1825), formerly Dendropoma maximum, was subject to a sudden, massive die-off in the Society Islands, French Polynesia, in 2015. On Mo'orea, where we have detailed documentation of the die-off, these gastropods were previously found in densities up to 165 m-2. In July 2015, we surveyed shallow back reefs of Mo'orea before, during and after the die-off, documenting their swift decline. All censused populations incurred 100% mortality. Additional surveys and observations from Mo'orea, Tahiti, Bora Bora, and Huahine (but not Taha'a) suggested a similar, and approximately simultaneous, die-off. The cause(s) of this cataclysmic mass mortality are currently unknown. Given the previously documented negative effects of C. maximum on corals, we expect the die-off will have cascading effects on the reef community.

  4. MXLKID: a maximum likelihood parameter identifier

    International Nuclear Information System (INIS)

    Gavel, D.T.

    1980-07-01

    MXLKID (MaXimum LiKelihood IDentifier) is a computer program designed to identify unknown parameters in a nonlinear dynamic system. Using noisy measurement data from the system, the maximum likelihood identifier computes a likelihood function (LF). Identification of system parameters is accomplished by maximizing the LF with respect to the parameters. The main body of this report briefly summarizes the maximum likelihood technique and gives instructions and examples for running the MXLKID program. MXLKID is implemented LRLTRAN on the CDC7600 computer at LLNL. A detailed mathematical description of the algorithm is given in the appendices. 24 figures, 6 tables

  5. The Control of Transmitted Power in an Active Isolation System

    DEFF Research Database (Denmark)

    Elliott, S.J.; Gardonio, P.; Pinnington, R.J.

    1997-01-01

    The isolation of vibration through a system with multiple active mounts is discussed, in which each of the mounts can transmit vibration in several degrees of freedom. Theoretical models of the various parts of this system have been developed which include a flexible receiving structure and distr......The isolation of vibration through a system with multiple active mounts is discussed, in which each of the mounts can transmit vibration in several degrees of freedom. Theoretical models of the various parts of this system have been developed which include a flexible receiving structure...... and distributed active mounts, and these models can be connected together to produce an overall theoretical description of a realistic active isolation system. Total transmitted power has been found to be an excellent criterion to quantify the effect of various control strategies in this model in which...... the contributions to the transmitted power in the various degrees of freedom can be clearly understood. It has also been found, however, that an active control system which minimises a practical estimate of transmitted power, calculated from the product of the axial forces and velocities under the mounts, can give...

  6. Influence of sexually transmitted infections in a horse breeding

    Directory of Open Access Journals (Sweden)

    Kosec Marjan

    2015-01-01

    Full Text Available The most frequent problems in horses reproduction are generally divided into those of infectious and non infectious etiology. Common causes of infectious diseases are usual­ly viruses and bacteria, and less frequently protozoa, mykoplasma and fungi. In this work there are presented the most important fact about sexually transmitted diseases, their clinical picture, risk factors, preventive measures as well as measures to prevent and eradicate the diseases. The biggest risk factor for sexually transmitted diseases in horses are breeding stallions, both in natural mating and in artificial insemination. Therefore, in order to prevent genital infections in horses, it is essential that the stallions used for breeding are healthy (non-infected. That can be determined with certainty only if the stallions are examined (tested just before the breeding season on most frequent sexually transmitted diseases (CEM,EAV. It is well known that in most cases the clinical picture of sexually transmitted diseses is not manifested on genitals. As well, variations in clinical picture can be expected also in mares, depending on the stage of the disease and its etiology. Harms arising from sexually transmitted diseases can be divided into direct and indirect. Direct damage occurs in the form of endometritis, miscarriage, stillbirths and births of weak foals, and indirect in restricting the traffic of infected and suspicios animals, isolation of the infected ones as well as medical treatment and interrupting mating.

  7. Current-mode minimax circuit

    NARCIS (Netherlands)

    Wassenaar, R.F.

    1992-01-01

    The minimum-maximum (minimax) circuit selects the minimum and maximum of two input currents. Four transistors in matched pairs are operated in the saturation region. Because the behavior of the circuit is based on matched devices and is independent of the relationship between the drain current and

  8. How long do centenarians survive? Life expectancy and maximum lifespan.

    Science.gov (United States)

    Modig, K; Andersson, T; Vaupel, J; Rau, R; Ahlbom, A

    2017-08-01

    The purpose of this study was to explore the pattern of mortality above the age of 100 years. In particular, we aimed to examine whether Scandinavian data support the theory that mortality reaches a plateau at particularly old ages. Whether the maximum length of life increases with time was also investigated. The analyses were based on individual level data on all Swedish and Danish centenarians born from 1870 to 1901; in total 3006 men and 10 963 women were included. Birth cohort-specific probabilities of dying were calculated. Exact ages were used for calculations of maximum length of life. Whether maximum age changed over time was analysed taking into account increases in cohort size. The results confirm that there has not been any improvement in mortality amongst centenarians in the past 30 years and that the current rise in life expectancy is driven by reductions in mortality below the age of 100 years. The death risks seem to reach a plateau of around 50% at the age 103 years for men and 107 years for women. Despite the rising life expectancy, the maximum age does not appear to increase, in particular after accounting for the increasing number of individuals of advanced age. Mortality amongst centenarians is not changing despite improvements at younger ages. An extension of the maximum lifespan and a sizeable extension of life expectancy both require reductions in mortality above the age of 100 years. © 2017 The Association for the Publication of the Journal of Internal Medicine.

  9. LANSCE beam current limiter

    International Nuclear Information System (INIS)

    Gallegos, F.R.

    1996-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. Active instrumentation, such as the Beam Current Limiter, is a component of the RSS. The current limiter is designed to limit the average current in a beam line below a specific level, thus minimizing the maximum current available for a beam spill accident. The beam current limiter is a self-contained, electrically isolated toroidal beam transformer which continuously monitors beam current. It is designed as fail-safe instrumentation. The design philosophy, hardware design, operation, and limitations of the device are described

  10. Maximum neutron flux in thermal reactors

    International Nuclear Information System (INIS)

    Strugar, P.V.

    1968-12-01

    Direct approach to the problem is to calculate spatial distribution of fuel concentration if the reactor core directly using the condition of maximum neutron flux and comply with thermal limitations. This paper proved that the problem can be solved by applying the variational calculus, i.e. by using the maximum principle of Pontryagin. Mathematical model of reactor core is based on the two-group neutron diffusion theory with some simplifications which make it appropriate from maximum principle point of view. Here applied theory of maximum principle are suitable for application. The solution of optimum distribution of fuel concentration in the reactor core is obtained in explicit analytical form. The reactor critical dimensions are roots of a system of nonlinear equations and verification of optimum conditions can be done only for specific examples

  11. Maximum allowable load on wheeled mobile manipulators

    International Nuclear Information System (INIS)

    Habibnejad Korayem, M.; Ghariblu, H.

    2003-01-01

    This paper develops a computational technique for finding the maximum allowable load of mobile manipulator during a given trajectory. The maximum allowable loads which can be achieved by a mobile manipulator during a given trajectory are limited by the number of factors; probably the dynamic properties of mobile base and mounted manipulator, their actuator limitations and additional constraints applied to resolving the redundancy are the most important factors. To resolve extra D.O.F introduced by the base mobility, additional constraint functions are proposed directly in the task space of mobile manipulator. Finally, in two numerical examples involving a two-link planar manipulator mounted on a differentially driven mobile base, application of the method to determining maximum allowable load is verified. The simulation results demonstrates the maximum allowable load on a desired trajectory has not a unique value and directly depends on the additional constraint functions which applies to resolve the motion redundancy

  12. Maximum phytoplankton concentrations in the sea

    DEFF Research Database (Denmark)

    Jackson, G.A.; Kiørboe, Thomas

    2008-01-01

    A simplification of plankton dynamics using coagulation theory provides predictions of the maximum algal concentration sustainable in aquatic systems. These predictions have previously been tested successfully against results from iron fertilization experiments. We extend the test to data collect...

  13. Nematode infections: soil-transmitted helminths and trichinella.

    Science.gov (United States)

    Knopp, Stefanie; Steinmann, Peter; Keiser, Jennifer; Utzinger, Jürg

    2012-06-01

    Infection with soil-transmitted helminths occurs via ingestion of nematode eggs with contaminated food and water, via hands, or inhalation of dust, or by penetration of larvae through the skin. Trichinella infections are caused by the ingestion of larvae contained in undercooked meat. In highly endemic areas, preventive chemotherapy (ie, regular administration of anthelmintic drugs to at-risk populations) is the key strategy against soil-transmitted helminthiasis. Integrated control approaches, including improved hygiene, sanitation, and water, are required for lasting effects. Because of growing tourism, travel, and migration, clinicians and specialized travel clinics must remain aware of the diagnosis, prevention, and treatment of soil-transmitted helminth and Trichinella infections. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Maximum Likelihood Blind Channel Estimation for Space-Time Coding Systems

    Directory of Open Access Journals (Sweden)

    Hakan A. Çırpan

    2002-05-01

    Full Text Available Sophisticated signal processing techniques have to be developed for capacity enhancement of future wireless communication systems. In recent years, space-time coding is proposed to provide significant capacity gains over the traditional communication systems in fading wireless channels. Space-time codes are obtained by combining channel coding, modulation, transmit diversity, and optional receive diversity in order to provide diversity at the receiver and coding gain without sacrificing the bandwidth. In this paper, we consider the problem of blind estimation of space-time coded signals along with the channel parameters. Both conditional and unconditional maximum likelihood approaches are developed and iterative solutions are proposed. The conditional maximum likelihood algorithm is based on iterative least squares with projection whereas the unconditional maximum likelihood approach is developed by means of finite state Markov process modelling. The performance analysis issues of the proposed methods are studied. Finally, some simulation results are presented.

  15. Emergence of Arthropod Transmitted infections in Kennel Dogs

    Directory of Open Access Journals (Sweden)

    Javed Jameel

    Full Text Available Changing scenario of climate resulting from global warming and adversity of nature has also resulted in emergence and re-emergence of diseases transmitted by arthropods. Increasing trends of population growth of dogs has increased the chance of disease transmission due to readily available susceptible host. Babesiosis and Hepatozoonosis and Ehrlichiosis are the main arthropod borne diseases of dogs prevalent in India. The present article explains the importance of these arthropod transmitted infections in kennel dogs, research progress and reason for their emergence in the present scenario. [Vet. World 2011; 4(11.000: 522-528

  16. Integrated differential high-voltage transmitting circuit for CMUTs

    DEFF Research Database (Denmark)

    Llimos Muntal, Pere; Larsen, Dennis Øland; Farch, Kjartan

    2015-01-01

    In this paper an integrated differential high-voltage transmitting circuit for capacitive micromachined ultrasonic transducers (CMUTs) used in portable ultrasound scanners is designed and implemented in a 0.35 μm high-voltage process. Measurements are performed on the integrated circuit in order...... to assess its performance. The circuit generates pulses at differential voltage levels of 60V, 80V and 100 V, a frequency up to 5MHz and a measured driving strength of 1.75 V/ns with the CMUT connected. The total on-chip area occupied by the transmitting circuit is 0.18 mm2 and the power consumption...

  17. Transmit antenna selection based on shadowing side information

    KAUST Repository

    Yilmaz, Ferkan

    2011-05-01

    In this paper, we propose a new transmit antenna selection scheme based on shadowing side information. In the proposed scheme, single transmit antenna which has the highest shadowing coefficient is selected. By the proposed technique, usage of the feedback channel and channel estimation complexity at the receiver can be reduced. We consider independent but not identically distributed Generalized-K composite fading model, which is a general composite fading & shadowing channel model for wireless environments. Exact closed-form outage probability, moment generating function and symbol error probability expressions are derived. In addition, theoretical performance results are validated by Monte Carlo simulations. © 2011 IEEE.

  18. Transmit antenna selection based on shadowing side information

    KAUST Repository

    Yilmaz, Ferkan; Yilmaz, Ahmet Oǧuz; Alouini, Mohamed-Slim; Kucur, Oǧuz

    2011-01-01

    In this paper, we propose a new transmit antenna selection scheme based on shadowing side information. In the proposed scheme, single transmit antenna which has the highest shadowing coefficient is selected. By the proposed technique, usage of the feedback channel and channel estimation complexity at the receiver can be reduced. We consider independent but not identically distributed Generalized-K composite fading model, which is a general composite fading & shadowing channel model for wireless environments. Exact closed-form outage probability, moment generating function and symbol error probability expressions are derived. In addition, theoretical performance results are validated by Monte Carlo simulations. © 2011 IEEE.

  19. An Accurate Transmitting Power Control Method in Wireless Communication Transceivers

    Science.gov (United States)

    Zhang, Naikang; Wen, Zhiping; Hou, Xunping; Bi, Bo

    2018-01-01

    Power control circuits are widely used in transceivers aiming at stabilizing the transmitted signal power to a specified value, thereby reducing power consumption and interference to other frequency bands. In order to overcome the shortcomings of traditional modes of power control, this paper proposes an accurate signal power detection method by multiplexing the receiver and realizes transmitting power control in the digital domain. The simulation results show that this novel digital power control approach has advantages of small delay, high precision and simplified design procedure. The proposed method is applicable to transceivers working at large frequency dynamic range, and has good engineering practicability.

  20. Maximum Power Point Tracking Based on Sliding Mode Control

    Directory of Open Access Journals (Sweden)

    Nimrod Vázquez

    2015-01-01

    Full Text Available Solar panels, which have become a good choice, are used to generate and supply electricity in commercial and residential applications. This generated power starts with the solar cells, which have a complex relationship between solar irradiation, temperature, and output power. For this reason a tracking of the maximum power point is required. Traditionally, this has been made by considering just current and voltage conditions at the photovoltaic panel; however, temperature also influences the process. In this paper the voltage, current, and temperature in the PV system are considered to be a part of a sliding surface for the proposed maximum power point tracking; this means a sliding mode controller is applied. Obtained results gave a good dynamic response, as a difference from traditional schemes, which are only based on computational algorithms. A traditional algorithm based on MPPT was added in order to assure a low steady state error.

  1. Spatio-temporal distribution of soil-transmitted helminth infections in Brazil.

    Science.gov (United States)

    Chammartin, Frédérique; Guimarães, Luiz H; Scholte, Ronaldo Gc; Bavia, Mara E; Utzinger, Jürg; Vounatsou, Penelope

    2014-09-18

    In Brazil, preventive chemotherapy targeting soil-transmitted helminthiasis is being scaled-up. Hence, spatially explicit estimates of infection risks providing information about the current situation are needed to guide interventions. Available high-resolution national model-based estimates either rely on analyses of data restricted to a given period of time, or on historical data collected over a longer period. While efforts have been made to take into account the spatial structure of the data in the modelling approach, little emphasis has been placed on the temporal dimension. We extracted georeferenced survey data on the prevalence of infection with soil-transmitted helminths (i.e. Ascaris lumbricoides, hookworm and Trichuris trichiura) in Brazil from the Global Neglected Tropical Diseases (GNTD) database. Selection of the most important predictors of infection risk was carried out using a Bayesian geostatistical approach and temporal models that address non-linearity and correlation of the explanatory variables. The spatial process was estimated through a predictive process approximation. Spatio-temporal models were built on the selected predictors with integrated nested Laplace approximation using stochastic partial differential equations. Our models revealed that, over the past 20 years, the risk of soil-transmitted helminth infection has decreased in Brazil, mainly because of the reduction of A. lumbricoides and hookworm infections. From 2010 onwards, we estimate that the infection prevalences with A. lumbricoides, hookworm and T. trichiura are 3.6%, 1.7% and 1.4%, respectively. We also provide a map highlighting municipalities in need of preventive chemotherapy, based on a predicted soil-transmitted helminth infection risk in excess of 20%. The need for treatments in the school-aged population at the municipality level was estimated at 1.8 million doses of anthelminthic tablets per year. The analysis of the spatio-temporal aspect of the risk of infection

  2. Soil-transmitted Helminthiasis in the United States: a systematic review--1940-2010.

    Science.gov (United States)

    Starr, Michelle C; Montgomery, Susan P

    2011-10-01

    The epidemiology of soil-transmitted helminth infections (hookworm, Trichuris trichiura, Ascaris lumbricoides, and Strongyloides stercoralis) in the United States is poorly understood. To gain understanding of the status of disease, a systematic review was performed to assess the prevalence of soil-transmitted helminth infections in the United States. Of all studies reviewed, 14 were designated as high-quality. High-quality studies were published from 1942 to 1982 and showed that infection was prevalent throughout the southern United States and Appalachia as recently as 1982, finding that hookworm (19.6%), T. trichiura (55.2%), A. lumbricoides (49.4%), and S. stercoralis (3.8%) affected significant percentages of the population. However, because the most recent high-quality studies were published over 25 years ago, the literature does not provide sufficient data to assess current endemic transmission. Because the status of disease remains unclear, there is a need for additional studies to determine if soil-transmitted helminths remain endemic in the United States.

  3. Transfusion transmitted malaria in three major blood banks of ...

    African Journals Online (AJOL)

    This study estimates the risk of acquiring malaria from a single unit of blood in North of Pakistan. A prospective study was conducted to investigate transfusion transmitted malaria in three major blood banks of Peshawar, Pakistan. A total of 1558 (1534 males and 24 females) healthy volunteer blood donors were screened for ...

  4. Adaptive single-antenna transmit selection with interference suppression

    KAUST Repository

    Radaydeh, Redha Mahmoud Mesleh

    2011-10-01

    This paper studies the performance of adaptive transmit selection with co-channel interference suppression in multipath fading channels. The adaptive selection algorithms are configured for single-antenna bandwidth-efficient or power-efficient transmission with as low transmit channel estimations as possible. Due to the fact that the number of active co-channel interfering signals and their corresponding powers experience random behavior, the adaptation to channels conditions, assuming uniform buffer and traffic loading, is proposed to be jointly based on the transmit channels instantaneous signal-to-noise ratios (SNRs) and signal-to-interference-plus-noise ratios (SINRs). Two interference cancelation algorithms are considered. The first algorithm assumes that the receiver eliminates the impact of the strongest subset of interferers, whereas the second algorithm suggests random cancelation of interferers to further reduce processing complexity. The impact of outdated ordering of interferers powers on the efficiency of interference cancelation, and the effect of imperfect prediction of transmit channels for desired user adaptation are investigated. Analytical formulations for various performance measures and comparisons between the performance and processing complexity of different adaptation schemes are presented. © 2011 IEEE.

  5. Risk behaviors for sexually transmitted diseases among crack users

    Directory of Open Access Journals (Sweden)

    Rafael Alves Guimarães

    2015-08-01

    Full Text Available AbstractObjectives: to investigate the prevalence and risk behaviors by means of reporting of sexually transmitted diseases among crack users.Method: cross-sectional study carried out with 588 crack users in a referral care unit for the treatment of chemical dependency. Data were collected by means of face-to-face interview and analyzed using Stata statistical software, version 8.0.Results: of the total participants, 154 (26.2%; 95% CI: 22.8-29.9 reported antecedents of sexually transmitted diseases. Ages between 25 and 30 years (RP: 2.1; 95% CI: 1.0-4.0 and over 30 years (RP: 3.8; 95% CI: 2.1-6.8, alcohol consumption (RP: 1.9; 95% CI: 1.1-3.3, antecedents of prostitution (RP: 1.9; 95% CI: 1.3-2.9 and sexual intercourse with person living with human immunodeficiency virus/AIDS (RP: 2.7; 95% CI: 1.8-4.2 were independently associated with reporting of sexually transmitted diseases.Conclusion: the results of this study suggest high risk and vulnerability of crack users for sexually transmitted diseases.

  6. Nurses stigmatization of sufferers of sexually transmitted diseases ...

    African Journals Online (AJOL)

    This study's objective is to assess nurses' stigmatization of sufferers of sexual transmitted diseases and its implications on treatment options. The study's method was the survey research through structured questionnaire and interview technique for selected sample of students and nurses. The multistage random sampling ...

  7. High rate of teenage pregnancy and sexually transmitted infections ...

    African Journals Online (AJOL)

    There is increased in teenage pregnancy despite the presence of dual protection practice and health care awareness programmes related to health and sexuality education in South Africa. The present study explores the underlying causes of high teenage pregnancy and sexually transmitted diseases rates, including HIV ...

  8. Device for transmitting pictures and device for receiving said pictures

    NARCIS (Netherlands)

    1993-01-01

    Device for transmitting television pictures in the form of transform coefficients and motion vectors. The motion vectors of a sub-picture are converted (20) into a series of difference vectors and a reference vector. Said series is subsequently applied to a variable-length encoder (22) which encodes

  9. A review of sexually transmitted diseases (STDs) of parasitic origin ...

    African Journals Online (AJOL)

    fore a now recognized mode of transmission – sexual contact. This in turn has led to giardiasis being classified as a sexually transmitted disease by the Centre for Disease Control and Prevention (CDC) in the United States. This review identifies its occurrence mainly in homosexual populations of the developed world ...

  10. The prevalence of transfusion-transmitted virus (TTV) infection in ...

    African Journals Online (AJOL)

    Transfusion-transmitted virus (TTV) is an unenveloped circular single-stranded DNA virus with a diameter of 30 to 32 nm that was first described in 1997 in Japan. TTV was detected in various populations without proven pathology, including blood donors and in patients with chronic hepatitis B virus (HBV) and hepatitis C ...

  11. Sexually transmitted infection incidence among adolescents in Ireland.

    LENUS (Irish Health Repository)

    Davoren, Martin P

    2014-10-01

    The burden of sexually transmitted infections (STIs) rests with young people, yet in Ireland there has been very little research into this population. The purpose of this study was to determine the incidence rate and establish risk factors that predict STI occurrence among adolescents in Ireland.

  12. Transfusion transmitted infections – A retrospective analysis from the ...

    African Journals Online (AJOL)

    Background: The emergence of transfusion transmitted infection (TTI) especially HIV/AIDS has created a huge obstacle in ensuring blood safety. To assess the situation in Eritrea, we carried out a retrospective study of 29,501 blood donors for the prevalence of TTI's i.e. HIV, HBV, HCV and Syphilis. Methods: The study ...

  13. An autochthonous sexually transmitted Zika virus infection in Italy 2016.

    Science.gov (United States)

    Grossi, Paolo Antonio; Percivalle, Elena; Campanini, Giulia; Sarasini, Antonella; Premoli, Marta; Zavattoni, Maurizio; Girello, Alessia; Dalla Gasperina, Daniela; Balsamo, Maria Luisa; Baldanti, Fausto; Rovida, Francesca

    2018-01-01

    We describe two cases of Zika virus infection involving an Italian patient returning from the Dominican Republic and his wife, who remained in Italy and had not travelled to Zika virus endemic areas in the previous months. The infection was transmitted through unprotected sexual intercourse after the man's return to Italy.

  14. Knowledge and practices related to sexually transmitted infections ...

    African Journals Online (AJOL)

    Background: Sexually transmitted infections (STIs) still stand as one of the commonest health problems affecting women of reproductive age. The knowledge and .... With the help of local leaders, one of 4 in- terview teams approached ... Ethical clearance to conduct the study was sought from the Makerere University School ...

  15. Geospatial forecast model for tsetse-transmitted animal ...

    African Journals Online (AJOL)

    Results indicate that GIS model developed for parasitic diseases based on growing degree day (GDD) concept can be applied to tsetse-transmitted trypanosomosis. GIS for animal trypanosomosis was created using Food and Agriculture Organization – Crop Production System Zones (FAO-CPSZ) database and Normalized ...

  16. Sexually transmitted infections, including HIV, in the Netherlands in 2008.

    NARCIS (Netherlands)

    Koedijk, F.D.H.; Vriend, H.J.; Veen, M.G. van; Coul, E.L.M. Op de; Broek, I.V.F. van den; Sighem, A.I. van; Verheij, R.A.; Sande, M.A.B. van der

    2009-01-01

    Chlamydia, gonorrhoea and syphilis. Chlamydia was the most common bacterial sexual transmitted infection (STI) diagnosed in Dutch STI centres in 2008. Similar to previous years, infections were reported as occurring especially in young heterosexuals and men who have sex with men (MSM) in 2008, the

  17. Profile Of Sexually Transmitted Diseases In And Around Lucknow

    Directory of Open Access Journals (Sweden)

    Jaiswal A K

    2002-01-01

    Full Text Available A retrospective study was undertaken from the year 1988 to 1998 to study the pattern of sexually transmitted diseases in and around Lucknow. Among 1890 patients examined, chancroid predominated followed by syphilis, gonorrhoea, genital warts, herpes genitalis, LGV and non-specific urethritis. The incidence of donovanosis was the lowest.

  18. partner notification in the management of sexually transmitted

    African Journals Online (AJOL)

    hi-tech

    2003-12-12

    Dec 12, 2003 ... Objective: To assess utilization of partner notification as a tool in prevention and control of Sexually transmitted ... being out of town (44.6%) fear of quarrels and violence from partners (32.5%) and ..... More than half of the men in this study reported ... patients give reasons that justify their actions. Such.

  19. Draft genome sequence of the sexually transmitted pathogen Trichomonas vaginalis

    DEFF Research Database (Denmark)

    Carlton, Jane M.; Hirt, Robert P.; Silva, Joana C.

    2007-01-01

    We describe the genome sequence of the protist Trichomonas vaginalis, a sexually transmitted human pathogen. Repeats and transposable elements comprise about two-thirds of the approximately 160-megabase genome, reflecting a recent massive expansion of genetic material. This expansion...... environment. The genome sequence predicts previously unknown functions for the hydrogenosome, which support a common evolutionary origin of this unusual organelle with mitochondria....

  20. Sexually transmitted infections and mate-finding Allee effects

    Czech Academy of Sciences Publication Activity Database

    Berec, Luděk; Janoušková, E.; Theuer, M.

    2017-01-01

    Roč. 114, APR 01 (2017), s. 59-69 ISSN 0040-5809 Institutional support: RVO:60077344 Keywords : Allee effect * mating * sexually transmitted disease Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 1.613, year: 2016 http://www.sciencedirect.com/science/article/pii/S0040580916301186

  1. Mechanical transport and dissemination of soil-transmitted helminth ...

    African Journals Online (AJOL)

    In previous studies, helminth eggs were isolated from wild-caught Musca domestica L. (Diptera: Muscidae). This laboratory study investigated the potential of the fly for mechanical transport and transmission of soil-transmitted helminths. Naïve, 2-3 day old, laboratory-reared adult flies were exposed to a mixture of Ascaris ...

  2. ABO, rhesus blood groups and transfusion-transmitted infections ...

    African Journals Online (AJOL)

    Background: Few studies focused on the study of blood groups in Gabon. This study aimed to determine the phenotypic frequency of ABO and Rhesus antigens in blood donors of Libreville and to assess the association between ABO blood groups and transfusion-transmitted infections. Materials and Methods: The study of ...

  3. Some models for epidemics of vector-transmitted diseases

    Directory of Open Access Journals (Sweden)

    Fred Brauer

    2016-10-01

    Full Text Available Vector-transmitted diseases such as dengue fever and chikungunya have been spreading rapidly in many parts of the world. The Zika virus has been known since 1947 and invaded South America in 2013. It can be transmitted not only by (mosquito vectors but also directly through sexual contact. Zika has developed into a serious global health problem because, while most cases are asymptomatic or very light, babies born to Zika - infected mothers may develop microcephaly and other very serious birth defects.We formulate and analyze two epidemic models for vector-transmitted diseases, one appropriate for dengue and chikungunya fever outbreaks and one that includes direct transmission appropriate for Zika virus outbreaks. This is especially important because the Zika virus is the first example of a disease that can be spread both indirectly through a vector and directly (through sexual contact. In both cases, we obtain expressions for the basic reproduction number and show how to use the initial exponential growth rate to estimate the basic reproduction number. However, for the model that includes direct transmission some additional data would be needed to identify the fraction of cases transmitted directly. Data for the 2015 Zika virus outbreak in Barranquilla, Colombia has been used to fit parameters to the model developed here and to estimate the basic reproduction number.

  4. Multielement Synthetic Transmit Aperture Imaging Using Temporal Encoding

    DEFF Research Database (Denmark)

    Gammelmark, Kim; Jensen, Jørgen Arendt

    2003-01-01

    A new method to increase the signal-to-noise ratio (SNR) of synthetic transmit aperture imaging is investigated. The approach utilizes multiple elements to emulate a spherical wave, and the conventional short excitation pulse is replaced by a linear frequency-modulated (FM) signal. The approach i...

  5. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    NARCIS (Netherlands)

    Wang, Y.; Leus, G.; Van der Veen, A.J.

    2009-01-01

    A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR) ultra-wideband (UWB) system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI) and the

  6. Comparative Costs of Antibacterial Usage in Sexually Transmitted ...

    African Journals Online (AJOL)

    Erah

    Purpose: To evaluate the cost of antibacterial usage to patients in a tertiary health facility in Nigeria. Methods: Drug utilization evaluation was carried out retrospectively among patients with sexually transmitted infections (STIs) over a one-year period between 2005 and 2006 in Lagos University. Teaching Hospital (LUTH) ...

  7. Stigma and stereotypes: women and sexually transmitted infections.

    Science.gov (United States)

    East, Leah; Jackson, Debra; O'Brien, Louise; Peters, Kathleen

    2012-01-01

    Sexually transmitted infections have long been associated with stigma and stereotypes due to their very nature. Throughout history sexually transmitted infections have been associated with female prostitution and deviant immoral behaviour making women who contract these infections particularly vulnerable to being stigmatised and stereotyped. Although the stigma attached to such infections has previously been documented in the literature, the aim of this research was to gain in depth insight into young Australian women's experiences of having a sexually transmitted infection from a feminist perspective. Findings from this study provide insight into the onerous effects stigma can have on women with these infections and sheds light on how these effects can influence self-perceptions, fear of rejection and feelings of unworthiness. These findings can provide nurses with greater understanding and insight into the effects of stigma on women's experiences of having a sexually transmitted infection. Having this understanding and insight has the potential to promote therapeutic care and minimise the stigma that may be felt among women who have contracted this type of infection.

  8. Transmit beamforming for optimal second-harmonic generation.

    Science.gov (United States)

    Hoilund-Kaupang, Halvard; Masoy, Svein-Erik

    2011-08-01

    A simulation study of transmit ultrasound beams from several transducer configurations is conducted to compare second-harmonic imaging at 3.5 MHz and 11 MHz. Second- harmonic generation and the ability to suppress near field echoes are compared. Each transducer configuration is defined by a chosen f-number and focal depth, and the transmit pressure is estimated to not exceed a mechanical index of 1.2. The medium resembles homogeneous muscle tissue with nonlinear elasticity and power-law attenuation. To improve computational efficiency, the KZK equation is utilized, and all transducers are circular-symmetric. Previous literature shows that second-harmonic generation is proportional to the square of the transmit pressure, and that transducer configurations with different transmit frequencies, but equal aperture and focal depth in terms of wavelengths, generate identical second-harmonic fields in terms of shape. Results verify this for a medium with attenuation f1. For attenuation f1.1, deviations are found, and the high frequency subsequently performs worse than the low frequency. The results suggest that high frequencies are less able to suppress near-field echoes in the presence of a heterogeneous body wall than low frequencies.

  9. Effect of window glazing on colour quality of transmitted daylight

    NARCIS (Netherlands)

    Dangol, R.; Kruisselbrink, T.W.; Rosemann, A.L.P.

    2017-01-01

    In this study, the colour quality of the daylight transmitted through different window glazing types is evaluated. The analysis considered four different types of window glazing: laminated, monolithic, coated and applied film glazing ranging in luminous transmittance from around 0.97 to <0.1. The

  10. Maximum gravitational redshift of white dwarfs

    International Nuclear Information System (INIS)

    Shapiro, S.L.; Teukolsky, S.A.

    1976-01-01

    The stability of uniformly rotating, cold white dwarfs is examined in the framework of the Parametrized Post-Newtonian (PPN) formalism of Will and Nordtvedt. The maximum central density and gravitational redshift of a white dwarf are determined as functions of five of the nine PPN parameters (γ, β, zeta 2 , zeta 3 , and zeta 4 ), the total angular momentum J, and the composition of the star. General relativity predicts that the maximum redshifts is 571 km s -1 for nonrotating carbon and helium dwarfs, but is lower for stars composed of heavier nuclei. Uniform rotation can increase the maximum redshift to 647 km s -1 for carbon stars (the neutronization limit) and to 893 km s -1 for helium stars (the uniform rotation limit). The redshift distribution of a larger sample of white dwarfs may help determine the composition of their cores

  11. GOOD HOMOSEXUAL BEHAVIOUR DECREASE PREVALENCE OF SEXUAL TRANSMITTED DISSEASE

    Directory of Open Access Journals (Sweden)

    Purwaningsih Purwaningsih

    2017-07-01

    Full Text Available Introduction: The homosexual behaviour were become indicators of sexually transmitted diseases’s (STDs prevalencies. Prevalence of sexually transmitted diseases in homosexual community was very high but until recently study it was conducted sporadically. The objective of this study was to analyze the correlation of homosexual behaviour with prevalence of sexually transmitted diseases (STDs in Mobile Clinic Community Centre of IGAMA collaborating with Public Health Centre Sumberpucung of Malang Regency. Method:  Analytic design with cross sectional methode was used in this study. The population were all visitors of Mobile Clinic Community Centre of IGAMA collaborating with Public Health Centre Sumberpucung of Malang Regency (353 people. Sample were 40 people who met to the inclusion criteria. The independent variable was homosexual behaviour and the dependent variable was prevalence of sexually transmitted diseases (STDs. Data for homosexual behaviour were collected by using questionnaire and indhept interview with content analyze and data for prevalence of sexually transmitted diseases (STDs were collected by using laboratorium test for STDs. Result: The research result was presented in the form diagram, table of cross tabulation and analyzed by using Spearman Rho with significance level ρ=0.005. The result showed that there was correlation of homosexual knowledge (ρ=0.001, attitude (ρ=0.000 and  practice (ρ=0.000 with prevalence of STDs. Dsicussion:  It can be concluded that the better knowledge, attitude and practice of homosexual could be decrease prevalence of STDs. Futher studies are recomended to analyze the correlation between homosexual behaviour and prevalence of STDs with Health Believe approach.

  12. Signaling Architectures that Transmit Unidirectional Information Despite Retroactivity.

    Science.gov (United States)

    Shah, Rushina; Del Vecchio, Domitilla

    2017-08-08

    A signaling pathway transmits information from an upstream system to downstream systems, ideally in a unidirectional fashion. A key obstacle to unidirectional transmission is retroactivity, the additional reaction flux that affects a system once its species interact with those of downstream systems. This raises the fundamental question of whether signaling pathways have developed specialized architectures that overcome retroactivity and transmit unidirectional signals. Here, we propose a general procedure based on mathematical analysis that provides an answer to this question. Using this procedure, we analyze the ability of a variety of signaling architectures to transmit one-way (from upstream to downstream) signals, as key biological parameters are tuned. We find that single stage phosphorylation and phosphotransfer systems that transmit signals from a kinase show a stringent design tradeoff that hampers their ability to overcome retroactivity. Interestingly, cascades of these architectures, which are highly represented in nature, can overcome this tradeoff and thus enable unidirectional transmission. By contrast, phosphotransfer systems, and single and double phosphorylation cycles that transmit signals from a substrate, are unable to mitigate retroactivity effects, even when cascaded, and hence are not well suited for unidirectional information transmission. These results are largely independent of the specific reaction-rate constant values, and depend on the topology of the architectures. Our results therefore identify signaling architectures that, allowing unidirectional transmission of signals, embody modular processes that conserve their input/output behavior across multiple contexts. These findings can be used to decompose natural signal transduction networks into modules, and at the same time, they establish a library of devices that can be used in synthetic biology to facilitate modular circuit design. Copyright © 2017 Biophysical Society. Published by

  13. Maximum entropy analysis of EGRET data

    DEFF Research Database (Denmark)

    Pohl, M.; Strong, A.W.

    1997-01-01

    EGRET data are usually analysed on the basis of the Maximum-Likelihood method \\cite{ma96} in a search for point sources in excess to a model for the background radiation (e.g. \\cite{hu97}). This method depends strongly on the quality of the background model, and thus may have high systematic unce...... uncertainties in region of strong and uncertain background like the Galactic Center region. Here we show images of such regions obtained by the quantified Maximum-Entropy method. We also discuss a possible further use of MEM in the analysis of problematic regions of the sky....

  14. The Maximum Resource Bin Packing Problem

    DEFF Research Database (Denmark)

    Boyar, J.; Epstein, L.; Favrholdt, L.M.

    2006-01-01

    Usually, for bin packing problems, we try to minimize the number of bins used or in the case of the dual bin packing problem, maximize the number or total size of accepted items. This paper presents results for the opposite problems, where we would like to maximize the number of bins used...... algorithms, First-Fit-Increasing and First-Fit-Decreasing for the maximum resource variant of classical bin packing. For the on-line variant, we define maximum resource variants of classical and dual bin packing. For dual bin packing, no on-line algorithm is competitive. For classical bin packing, we find...

  15. Shower maximum detector for SDC calorimetry

    International Nuclear Information System (INIS)

    Ernwein, J.

    1994-01-01

    A prototype for the SDC end-cap (EM) calorimeter complete with a pre-shower and a shower maximum detector was tested in beams of electrons and Π's at CERN by an SDC subsystem group. The prototype was manufactured from scintillator tiles and strips read out with 1 mm diameter wave-length shifting fibers. The design and construction of the shower maximum detector is described, and results of laboratory tests on light yield and performance of the scintillator-fiber system are given. Preliminary results on energy and position measurements with the shower max detector in the test beam are shown. (authors). 4 refs., 5 figs

  16. Topics in Bayesian statistics and maximum entropy

    International Nuclear Information System (INIS)

    Mutihac, R.; Cicuttin, A.; Cerdeira, A.; Stanciulescu, C.

    1998-12-01

    Notions of Bayesian decision theory and maximum entropy methods are reviewed with particular emphasis on probabilistic inference and Bayesian modeling. The axiomatic approach is considered as the best justification of Bayesian analysis and maximum entropy principle applied in natural sciences. Particular emphasis is put on solving the inverse problem in digital image restoration and Bayesian modeling of neural networks. Further topics addressed briefly include language modeling, neutron scattering, multiuser detection and channel equalization in digital communications, genetic information, and Bayesian court decision-making. (author)

  17. Density estimation by maximum quantum entropy

    International Nuclear Information System (INIS)

    Silver, R.N.; Wallstrom, T.; Martz, H.F.

    1993-01-01

    A new Bayesian method for non-parametric density estimation is proposed, based on a mathematical analogy to quantum statistical physics. The mathematical procedure is related to maximum entropy methods for inverse problems and image reconstruction. The information divergence enforces global smoothing toward default models, convexity, positivity, extensivity and normalization. The novel feature is the replacement of classical entropy by quantum entropy, so that local smoothing is enforced by constraints on differential operators. The linear response of the estimate is proportional to the covariance. The hyperparameters are estimated by type-II maximum likelihood (evidence). The method is demonstrated on textbook data sets

  18. Maximum Mass of Hybrid Stars in the Quark Bag Model

    Science.gov (United States)

    Alaverdyan, G. B.; Vartanyan, Yu. L.

    2017-12-01

    The effect of model parameters in the equation of state for quark matter on the magnitude of the maximum mass of hybrid stars is examined. Quark matter is described in terms of the extended MIT bag model including corrections for one-gluon exchange. For nucleon matter in the range of densities corresponding to the phase transition, a relativistic equation of state is used that is calculated with two-particle correlations taken into account based on using the Bonn meson-exchange potential. The Maxwell construction is used to calculate the characteristics of the first order phase transition and it is shown that for a fixed value of the strong interaction constant αs, the baryon concentrations of the coexisting phases grow monotonically as the bag constant B increases. It is shown that for a fixed value of the strong interaction constant αs, the maximum mass of a hybrid star increases as the bag constant B decreases. For a given value of the bag parameter B, the maximum mass rises as the strong interaction constant αs increases. It is shown that the configurations of hybrid stars with maximum masses equal to or exceeding the mass of the currently known most massive pulsar are possible for values of the strong interaction constant αs > 0.6 and sufficiently low values of the bag constant.

  19. Direct maximum parsimony phylogeny reconstruction from genotype data.

    Science.gov (United States)

    Sridhar, Srinath; Lam, Fumei; Blelloch, Guy E; Ravi, R; Schwartz, Russell

    2007-12-05

    Maximum parsimony phylogenetic tree reconstruction from genetic variation data is a fundamental problem in computational genetics with many practical applications in population genetics, whole genome analysis, and the search for genetic predictors of disease. Efficient methods are available for reconstruction of maximum parsimony trees from haplotype data, but such data are difficult to determine directly for autosomal DNA. Data more commonly is available in the form of genotypes, which consist of conflated combinations of pairs of haplotypes from homologous chromosomes. Currently, there are no general algorithms for the direct reconstruction of maximum parsimony phylogenies from genotype data. Hence phylogenetic applications for autosomal data must therefore rely on other methods for first computationally inferring haplotypes from genotypes. In this work, we develop the first practical method for computing maximum parsimony phylogenies directly from genotype data. We show that the standard practice of first inferring haplotypes from genotypes and then reconstructing a phylogeny on the haplotypes often substantially overestimates phylogeny size. As an immediate application, our method can be used to determine the minimum number of mutations required to explain a given set of observed genotypes. Phylogeny reconstruction directly from unphased data is computationally feasible for moderate-sized problem instances and can lead to substantially more accurate tree size inferences than the standard practice of treating phasing and phylogeny construction as two separate analysis stages. The difference between the approaches is particularly important for downstream applications that require a lower-bound on the number of mutations that the genetic region has undergone.

  20. Nonsymmetric entropy and maximum nonsymmetric entropy principle

    International Nuclear Information System (INIS)

    Liu Chengshi

    2009-01-01

    Under the frame of a statistical model, the concept of nonsymmetric entropy which generalizes the concepts of Boltzmann's entropy and Shannon's entropy, is defined. Maximum nonsymmetric entropy principle is proved. Some important distribution laws such as power law, can be derived from this principle naturally. Especially, nonsymmetric entropy is more convenient than other entropy such as Tsallis's entropy in deriving power laws.

  1. Maximum speed of dewetting on a fiber

    NARCIS (Netherlands)

    Chan, Tak Shing; Gueudre, Thomas; Snoeijer, Jacobus Hendrikus

    2011-01-01

    A solid object can be coated by a nonwetting liquid since a receding contact line cannot exceed a critical speed. We theoretically investigate this forced wetting transition for axisymmetric menisci on fibers of varying radii. First, we use a matched asymptotic expansion and derive the maximum speed

  2. Maximum potential preventive effect of hip protectors

    NARCIS (Netherlands)

    van Schoor, N.M.; Smit, J.H.; Bouter, L.M.; Veenings, B.; Asma, G.B.; Lips, P.T.A.M.

    2007-01-01

    OBJECTIVES: To estimate the maximum potential preventive effect of hip protectors in older persons living in the community or homes for the elderly. DESIGN: Observational cohort study. SETTING: Emergency departments in the Netherlands. PARTICIPANTS: Hip fracture patients aged 70 and older who

  3. Maximum gain of Yagi-Uda arrays

    DEFF Research Database (Denmark)

    Bojsen, J.H.; Schjær-Jacobsen, Hans; Nilsson, E.

    1971-01-01

    Numerical optimisation techniques have been used to find the maximum gain of some specific parasitic arrays. The gain of an array of infinitely thin, equispaced dipoles loaded with arbitrary reactances has been optimised. The results show that standard travelling-wave design methods are not optimum....... Yagi–Uda arrays with equal and unequal spacing have also been optimised with experimental verification....

  4. correlation between maximum dry density and cohesion

    African Journals Online (AJOL)

    HOD

    represents maximum dry density, signifies plastic limit and is liquid limit. Researchers [6, 7] estimate compaction parameters. Aside from the correlation existing between compaction parameters and other physical quantities there are some other correlations that have been investigated by other researchers. The well-known.

  5. Weak scale from the maximum entropy principle

    Science.gov (United States)

    Hamada, Yuta; Kawai, Hikaru; Kawana, Kiyoharu

    2015-03-01

    The theory of the multiverse and wormholes suggests that the parameters of the Standard Model (SM) are fixed in such a way that the radiation of the S3 universe at the final stage S_rad becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the SM, we can check whether S_rad actually becomes maximum at the observed values. In this paper, we regard S_rad at the final stage as a function of the weak scale (the Higgs expectation value) vh, and show that it becomes maximum around vh = {{O}} (300 GeV) when the dimensionless couplings in the SM, i.e., the Higgs self-coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by vh ˜ T_{BBN}2 / (M_{pl}ye5), where ye is the Yukawa coupling of electron, T_BBN is the temperature at which the Big Bang nucleosynthesis starts, and M_pl is the Planck mass.

  6. The maximum-entropy method in superspace

    Czech Academy of Sciences Publication Activity Database

    van Smaalen, S.; Palatinus, Lukáš; Schneider, M.

    2003-01-01

    Roč. 59, - (2003), s. 459-469 ISSN 0108-7673 Grant - others:DFG(DE) XX Institutional research plan: CEZ:AV0Z1010914 Keywords : maximum-entropy method, * aperiodic crystals * electron density Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.558, year: 2003

  7. Achieving maximum sustainable yield in mixed fisheries

    NARCIS (Netherlands)

    Ulrich, Clara; Vermard, Youen; Dolder, Paul J.; Brunel, Thomas; Jardim, Ernesto; Holmes, Steven J.; Kempf, Alexander; Mortensen, Lars O.; Poos, Jan Jaap; Rindorf, Anna

    2017-01-01

    Achieving single species maximum sustainable yield (MSY) in complex and dynamic fisheries targeting multiple species (mixed fisheries) is challenging because achieving the objective for one species may mean missing the objective for another. The North Sea mixed fisheries are a representative example

  8. 5 CFR 534.203 - Maximum stipends.

    Science.gov (United States)

    2010-01-01

    ... maximum stipend established under this section. (e) A trainee at a non-Federal hospital, clinic, or medical or dental laboratory who is assigned to a Federal hospital, clinic, or medical or dental... Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PAY UNDER OTHER SYSTEMS Student...

  9. Minimal length, Friedmann equations and maximum density

    Energy Technology Data Exchange (ETDEWEB)

    Awad, Adel [Center for Theoretical Physics, British University of Egypt,Sherouk City 11837, P.O. Box 43 (Egypt); Department of Physics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Ali, Ahmed Farag [Centre for Fundamental Physics, Zewail City of Science and Technology,Sheikh Zayed, 12588, Giza (Egypt); Department of Physics, Faculty of Science, Benha University,Benha, 13518 (Egypt)

    2014-06-16

    Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

  10. Transition from Fowler-Nordheim field emission to space charge limited current density

    International Nuclear Information System (INIS)

    Feng, Y.; Verboncoeur, J. P.

    2006-01-01

    The Fowler-Nordheim law gives the current density extracted from a surface under strong fields, by treating the emission of electrons from a metal-vacuum interface in the presence of an electric field normal to the surface as a quantum mechanical tunneling process. Child's law predicts the maximum transmitted current density by considering the space charge effect. When the electric field becomes high enough, the emitted current density will be limited by Child's law. This work analyzes the transition of the transmitted current density from the Fowler-Nordheim law to Child's law space charge limit using a one-dimensional particle-in-cell code. Also studied is the response of the emission model to strong electric fields near the transition point. We find the transition without geometrical effort is smooth and much slower than reported previously [J. P. Barbour, W. W. Dolan, J. K. Trolan, E. E. Martin, and W. P. Dyke, Phys. Rev. 92, 45 (1953)]. We analyze the effects of geometric field enhancement and work function on the transition. Using our previous model for effective field enhancement [Y. Feng and J. P. Verboncoeur, Phys. Plasmas 12, 103301 (2005)], we find the geometric effect dominates, and enhancement β>10 can accelerate the approach to the space charge limit at practical electric field. A damped oscillation near the local plasma frequency is observed in the transient system response

  11. PTree: pattern-based, stochastic search for maximum parsimony phylogenies

    Directory of Open Access Journals (Sweden)

    Ivan Gregor

    2013-06-01

    Full Text Available Phylogenetic reconstruction is vital to analyzing the evolutionary relationship of genes within and across populations of different species. Nowadays, with next generation sequencing technologies producing sets comprising thousands of sequences, robust identification of the tree topology, which is optimal according to standard criteria such as maximum parsimony, maximum likelihood or posterior probability, with phylogenetic inference methods is a computationally very demanding task. Here, we describe a stochastic search method for a maximum parsimony tree, implemented in a software package we named PTree. Our method is based on a new pattern-based technique that enables us to infer intermediate sequences efficiently where the incorporation of these sequences in the current tree topology yields a phylogenetic tree with a lower cost. Evaluation across multiple datasets showed that our method is comparable to the algorithms implemented in PAUP* or TNT, which are widely used by the bioinformatics community, in terms of topological accuracy and runtime. We show that our method can process large-scale datasets of 1,000–8,000 sequences. We believe that our novel pattern-based method enriches the current set of tools and methods for phylogenetic tree inference. The software is available under: http://algbio.cs.uni-duesseldorf.de/webapps/wa-download/.

  12. PTree: pattern-based, stochastic search for maximum parsimony phylogenies.

    Science.gov (United States)

    Gregor, Ivan; Steinbrück, Lars; McHardy, Alice C

    2013-01-01

    Phylogenetic reconstruction is vital to analyzing the evolutionary relationship of genes within and across populations of different species. Nowadays, with next generation sequencing technologies producing sets comprising thousands of sequences, robust identification of the tree topology, which is optimal according to standard criteria such as maximum parsimony, maximum likelihood or posterior probability, with phylogenetic inference methods is a computationally very demanding task. Here, we describe a stochastic search method for a maximum parsimony tree, implemented in a software package we named PTree. Our method is based on a new pattern-based technique that enables us to infer intermediate sequences efficiently where the incorporation of these sequences in the current tree topology yields a phylogenetic tree with a lower cost. Evaluation across multiple datasets showed that our method is comparable to the algorithms implemented in PAUP* or TNT, which are widely used by the bioinformatics community, in terms of topological accuracy and runtime. We show that our method can process large-scale datasets of 1,000-8,000 sequences. We believe that our novel pattern-based method enriches the current set of tools and methods for phylogenetic tree inference. The software is available under: http://algbio.cs.uni-duesseldorf.de/webapps/wa-download/.

  13. Longitudinal and transverse space charge limitations on transport of maximum power beams

    International Nuclear Information System (INIS)

    Khoe, T.K.; Martin, R.L.

    1977-01-01

    The maximum transportable beam power is a critical issue in selecting the most favorable approach to generating ignition pulses for inertial fusion with high energy accelerators. Maschke and Courant have put forward expressions for the limits on transport power for quadrupole and solenoidal channels. Included in a more general way is the self consistent effect of space charge defocusing on the power limit. The results show that no limits on transmitted power exist in principal. In general, quadrupole transport magnets appear superior to solenoids except for transport of very low energy and highly charged particles. Longitudinal space charge effects are very significant for transport of intense beams

  14. Pattern formation, logistics, and maximum path probability

    Science.gov (United States)

    Kirkaldy, J. S.

    1985-05-01

    The concept of pattern formation, which to current researchers is a synonym for self-organization, carries the connotation of deductive logic together with the process of spontaneous inference. Defining a pattern as an equivalence relation on a set of thermodynamic objects, we establish that a large class of irreversible pattern-forming systems, evolving along idealized quasisteady paths, approaches the stable steady state as a mapping upon the formal deductive imperatives of a propositional function calculus. In the preamble the classical reversible thermodynamics of composite systems is analyzed as an externally manipulated system of space partitioning and classification based on ideal enclosures and diaphragms. The diaphragms have discrete classification capabilities which are designated in relation to conserved quantities by descriptors such as impervious, diathermal, and adiabatic. Differentiability in the continuum thermodynamic calculus is invoked as equivalent to analyticity and consistency in the underlying class or sentential calculus. The seat of inference, however, rests with the thermodynamicist. In the transition to an irreversible pattern-forming system the defined nature of the composite reservoirs remains, but a given diaphragm is replaced by a pattern-forming system which by its nature is a spontaneously evolving volume partitioner and classifier of invariants. The seat of volition or inference for the classification system is thus transferred from the experimenter or theoretician to the diaphragm, and with it the full deductive facility. The equivalence relations or partitions associated with the emerging patterns may thus be associated with theorems of the natural pattern-forming calculus. The entropy function, together with its derivatives, is the vehicle which relates the logistics of reservoirs and diaphragms to the analog logistics of the continuum. Maximum path probability or second-order differentiability of the entropy in isolation are

  15. Maximum power point tracker for photovoltaic power plants

    Science.gov (United States)

    Arcidiacono, V.; Corsi, S.; Lambri, L.

    The paper describes two different closed-loop control criteria for the maximum power point tracking of the voltage-current characteristic of a photovoltaic generator. The two criteria are discussed and compared, inter alia, with regard to the setting-up problems that they pose. Although a detailed analysis is not embarked upon, the paper also provides some quantitative information on the energy advantages obtained by using electronic maximum power point tracking systems, as compared with the situation in which the point of operation of the photovoltaic generator is not controlled at all. Lastly, the paper presents two high-efficiency MPPT converters for experimental photovoltaic plants of the stand-alone and the grid-interconnected type.

  16. Properties of high current RFQ injectors

    International Nuclear Information System (INIS)

    Schempp, A.; Goethe, J.W.

    1996-01-01

    RFQ linacs are efficient, compact low energy ion structures, which have found numerous applications. They use electrical rf focusing and can capture, bunch and transmit high current ion beams. Some recent development and new projects like a heavy ion injectors for a cyclotron, and the status of the work on high current high duty factor RFQs will be discussed. (author)

  17. Properties of high current RFQ injectors

    Energy Technology Data Exchange (ETDEWEB)

    Schempp, A.; Goethe, J.W. [Frankfurt Univ. (Germany). Inst. fuer Angewandte Physik

    1996-12-31

    RFQ linacs are efficient, compact low energy ion structures, which have found numerous applications. They use electrical rf focusing and can capture, bunch and transmit high current ion beams. Some recent development and new projects like a heavy ion injectors for a cyclotron, and the status of the work on high current high duty factor RFQs will be discussed. (author) 2 refs.

  18. Environmental pollution with soil-transmitted helminths in Sanliurfa, Turkey

    Directory of Open Access Journals (Sweden)

    Ulukanligil Mustafa

    2001-01-01

    Full Text Available Soil transmitted helminth (STH infection are endemic in developing countries. A study was carried out of sewage farms, streams and vegetables to determine the sources and routes of STH infection in Sanliurfa, Turkey. Stool samples from farmhouse inhabitants as well as soil and vegetable samples from the gardens were collected and examined. In addition, water samples from streams and vegetable samples from the city market were collected and examined. One hundred and eighty-seven (59.5% of a total of 314 samples, including 88.4% of the stool samples, 60.8% of the water samples, 84.4% of the soil samples and 14% of the vegetable samples, were found to be positive for STH eggs. These results indicate that the water, soil and vegetables are heavily contaminated, and suggest a vicious circle between humans and the environment. Improving environmental sanitation is imperative for the control of soil-transmitted helminthiasis in Sanliurfa.

  19. Spectrally efficient switched transmit diversity for spectrum sharing systems

    KAUST Repository

    Bouida, Zied; Abdallah, Mohamed M.; Qaraqe, Khalid A.; Alouini, Mohamed-Slim

    2011-01-01

    Under the scenario of an underlay cognitive radio network, we propose in this paper an adaptive scheme using switched transmit diversity and adaptive modulation in order to increase the spectral efficiency of the secondary link. The proposed bandwidth efficient scheme (BES) uses the scan and wait (SWC) combining technique where a transmission occurs only when a branch with an acceptable performance is found, otherwise data is buffered. In our scheme, the modulation constellation size and the used transmit branch are determined to achieve the highest spectral efficiency given the fading channel conditions, the required error rate performance, and a peak interference constraint to the primary receiver. Selected numerical examples show that the BES scheme increases the capacity of the secondary link when compared to an existing switching efficient scheme (SES). This spectral efficiency comes at the expense of an increased average number of switched branches and thus an increased average delay. © 2011 IEEE.

  20. Spectrally efficient switched transmit diversity for spectrum sharing systems

    KAUST Repository

    Bouida, Zied

    2011-09-01

    Under the scenario of an underlay cognitive radio network, we propose in this paper an adaptive scheme using switched transmit diversity and adaptive modulation in order to increase the spectral efficiency of the secondary link. The proposed bandwidth efficient scheme (BES) uses the scan and wait (SWC) combining technique where a transmission occurs only when a branch with an acceptable performance is found, otherwise data is buffered. In our scheme, the modulation constellation size and the used transmit branch are determined to achieve the highest spectral efficiency given the fading channel conditions, the required error rate performance, and a peak interference constraint to the primary receiver. Selected numerical examples show that the BES scheme increases the capacity of the secondary link when compared to an existing switching efficient scheme (SES). This spectral efficiency comes at the expense of an increased average number of switched branches and thus an increased average delay. © 2011 IEEE.

  1. Three Dimensional Energy Transmitting Boundary in the Time Domain

    Directory of Open Access Journals (Sweden)

    Naohiro eNakamura

    2015-11-01

    Full Text Available Although the energy transmitting boundary is accurate and efficient for the FEM earthquake response analysis, it could be applied in the frequency domain only. In the previous papers, the author proposed an earthquake response analysis method using the time domain energy transmitting boundary for two dimensional problems. In this paper, this technique is expanded for three dimensional problems. The inner field is supposed to be a hexahedron shape and the approximate time domain boundary is explained, first. Next, two dimensional anti-plane time domain boundary is studied for a part of the approximate three dimensional boundary method. Then, accuracy and efficiency of the proposed method are confirmed by example problems.

  2. Canadian Laboratory Standards for Sexually Transmitted Infections: Best Practice Guidelines

    Directory of Open Access Journals (Sweden)

    Max A Chernesky

    2005-01-01

    Full Text Available Sexually transmitted infections (STI continue to spread, and show no international boundaries. Diseases such as gonorrhea and syphilis, which we thought were under control in Canadian populations, have increased in incidence. Sexually transmitted or associated syndromes such as cervicitis, enteric infections, epididymitis, genital ulcers, sexually related hepatitis, ophthalmia neonatorum, pelvic inflammatory disease, prostatitis and vulvovaginitis present a challenge for the physician to identify the microbial cause, treat the patient and manage contacts. During the past 10 years, new technologies developed for the diagnosis of STIs have provided a clearer understanding of the real accuracy of traditional tests for the diagnosis of infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, herpes simplex viruses, hepatitis B virus, human papillomaviruses, HIV, Haemophilus ducreyi, Trichomonas vaginalis and mycoplasmas. This has presented a major challenge to the diagnostic laboratory, namely, selecting the most sensitive and specific test matched with the most appropriate specimens to provide meaningful and timely results to facilitate optimal patient care.

  3. Maximum concentrations at work and maximum biologically tolerable concentration for working materials 1991

    International Nuclear Information System (INIS)

    1991-01-01

    The meaning of the term 'maximum concentration at work' in regard of various pollutants is discussed. Specifically, a number of dusts and smokes are dealt with. The valuation criteria for maximum biologically tolerable concentrations for working materials are indicated. The working materials in question are corcinogeneous substances or substances liable to cause allergies or mutate the genome. (VT) [de

  4. 75 FR 43840 - Inflation Adjustment of the Ordinary Maximum and Aggravated Maximum Civil Monetary Penalties for...

    Science.gov (United States)

    2010-07-27

    ...-17530; Notice No. 2] RIN 2130-ZA03 Inflation Adjustment of the Ordinary Maximum and Aggravated Maximum... remains at $250. These adjustments are required by the Federal Civil Penalties Inflation Adjustment Act [email protected] . SUPPLEMENTARY INFORMATION: The Federal Civil Penalties Inflation Adjustment Act of 1990...

  5. Human bubonic plague transmitted by a domestic cat scratch.

    Science.gov (United States)

    Weniger, B G; Warren, A J; Forseth, V; Shipps, G W; Creelman, T; Gorton, J; Barnes, A M

    1984-02-17

    Bubonic plague was transmitted to a 10-year-old girl in Oregon by a scratch wound inflicted by a domestic cat. The cat probably was infected by contact with infected wild rodents or their fleas. Yersinia pestis was identified in Diamanus montanus fleas collected from an abandoned burrow near the patient's home. Domestic cats may infect humans with Y pestis by inoculation from a scratch.

  6. Congenitally transmitted visceral leishmaniasis: report of two brazilian human cases

    Directory of Open Access Journals (Sweden)

    Myrlena Regina Machado Mescouto-Borges

    2013-04-01

    Full Text Available Visceral leishmaniasis is a relevant public health problem worldwide. Most of the reported cases in Latin America are from Brazil. Herein we report two human cases of congenitally transmitted visceral leishmaniasis in two patients who developed symptoms during pregnancy. The diagnosis was made by visual examination of Leishmania parasites in bone marrow aspirates of the mothers and by detecting parasite kDNA in bone marrow samples of the newborn children using polymerase chain reaction.

  7. Using Piezoelectric Devices to Transmit Power through Walls

    Science.gov (United States)

    Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi

    2008-01-01

    A method denoted wireless acoustic-electric feed-through (WAEF) has been conceived for transmitting power and/or data signals through walls or other solid objects made of a variety of elastic materials that could be electrically conductive or nonconductive. WAEF would make it unnecessary to use wires, optical fibers, tubes, or other discrete wall-penetrating signal-transmitting components, thereby eliminating the potential for structural weakening or leakage at such penetrations. Avoidance of such penetrations could be essential in some applications in which maintenance of pressure, vacuum, or chemical or biological isolation is required. In a basic WAEF setup, a transmitting piezoelectric transducer on one side of a wall would be driven at resonance to excite ultrasonic vibrations in the wall. A receiving piezoelectric transducer on the opposite side of the wall would convert the vibrations back to an ultrasonic AC electric signal, which would then be detected and otherwise processed in a manner that would depend on the modulation (if any) applied to the signal and whether the signal was used to transmit power, data, or both. An electromechanical-network model has been derived as a computationally efficient means of analyzing and designing a WAEF system. This model is a variant of a prior model, known in the piezoelectric-transducer art as Mason's equivalent-circuit model, in which the electrical and mechanical dynamics, including electromechanical couplings, are expressed as electrical circuit elements that can include inductors, capacitors, and lumped-parameter complex impedances. The real parts of the complex impedances are used to account for dielectric, mechanical, and coupling losses in all components (including all piezoelectric-transducer, wall, and intermediate material layers). In an application to a three-layer piezoelectric structure, this model was shown to yield the same results as do solutions of the wave equations of piezoelectricity and acoustic

  8. Perception of health care providers about sexually transmitted infections

    International Nuclear Information System (INIS)

    Khan, A.; Izhar, V.

    2015-01-01

    Sexually transmitted infections represent a global health problem leading to social stigma and early morbidity and mortality. Prior to this study, different health care providers were dealing with sexually transmitted infections with various parameters and were not following the standard regime given by the WHO. The aim of this study was to investigate the perception of health care providers about sexually transmitted infections and its treatment guidelines. Methods: Cross sectional questionnaire based study was conducted from health care providers(specialists, family physicians, homeopaths and others )of Lahore from Jan 2014 to December 2014. Data was collected with consent through convenience purposive sampling of randomly selected 100 specialists, 200 family physicians, 100 homeopaths and 100 others. Trained investigators pre-tested the validity and reliability of the questionnaire before use. Data of response was coded, entered and analyzed using SPSS. Results: Out of 500 practitioners 475 (95%) completed the questionnaire. Those excluded were due to insufficient data in questionnaire. Almost all respondents were aware of STIs and the guidelines and claimed to have decent knowledge. Apart from some disagreement on the user- friendliness and communication facilitating properties, the health care provider's attitude were positive. Conclusion: Overall, all the health care providers knew about sexually transmitted infections. It was the treatment according to the guidelines, in which they differed. Specialists and Family physician in Lahore, Pakistan knew and followed the STIs guidelines while managing the patients. Homeopaths and others were receiving patients and treating most of these infections but were not aware of the standard guidelines yet somehow their patients were treated and satisfied. Enhancing the familiarity of the guidelines among users can result in a positive outcome on the treatment of STIs. (author)

  9. Automatic Identification System (AIS) Transmit Testing in Louisville Phase 2

    Science.gov (United States)

    2014-08-01

    Firewall Louisville QM 65.206.28.x NAIS Site Controller PC RS232 Serial cable TV32 Computer Cmd Center Serial splitter SAAB R40 AIS Base Station...172.17.14.6 Rack mount computer AIS Radio Interface Ethernet Switch 192.168.0.x Firewall Cable Modem 192.168.0.1 VTS Accred. Boundary serial connection...Automatic Identification System ( AIS ) Transmit Testing in Louisville Phase 2 Distribution Statement A: Approved for public release

  10. Pattern of Sexually Transmitted Diseases in and Around Udaipur

    Directory of Open Access Journals (Sweden)

    Nirmal Kumar Bansal

    1988-01-01

    Full Text Available The patients who attended the STD clinic of our hospital during the last 10 years were studied retrospectively to work out the pattern of major sexually transmitted diseases viz. -syphilis, ionorrhoea, chancroid, lymphogranuloma vencreum and donovinosis. The total number of patients was 1093, The relative incidence of chancroid was found. higher (37.78% than syphilis (32.47%, gonorrhoea (24 79% mixed infections (3.38%, donovanosis (1.18% and lymphogranuloma venereum (0.36%.

  11. Recommendation on vectors and vector-transmitted diseases

    OpenAIRE

    Netherlands Food and Consumer Product Safety Authority

    2009-01-01

    In view of their increasing risk of introduction and their possible implications in causing major disease outbreaks, vectors, as well as vector-transmitted diseases like dengue, West Nile disease, Lyme disease and bluetongue need to be recognised as a threat to public and animal health and to the economy, also in the Netherlands. There has been an increase in the incidence of these diseases in the past two to three decades. Climate changes and changes in the use of land, water managemen...

  12. Zipf's law, power laws and maximum entropy

    International Nuclear Information System (INIS)

    Visser, Matt

    2013-01-01

    Zipf's law, and power laws in general, have attracted and continue to attract considerable attention in a wide variety of disciplines—from astronomy to demographics to software structure to economics to linguistics to zoology, and even warfare. A recent model of random group formation (RGF) attempts a general explanation of such phenomena based on Jaynes' notion of maximum entropy applied to a particular choice of cost function. In the present paper I argue that the specific cost function used in the RGF model is in fact unnecessarily complicated, and that power laws can be obtained in a much simpler way by applying maximum entropy ideas directly to the Shannon entropy subject only to a single constraint: that the average of the logarithm of the observable quantity is specified. (paper)

  13. Maximum-entropy description of animal movement.

    Science.gov (United States)

    Fleming, Chris H; Subaşı, Yiğit; Calabrese, Justin M

    2015-03-01

    We introduce a class of maximum-entropy states that naturally includes within it all of the major continuous-time stochastic processes that have been applied to animal movement, including Brownian motion, Ornstein-Uhlenbeck motion, integrated Ornstein-Uhlenbeck motion, a recently discovered hybrid of the previous models, and a new model that describes central-place foraging. We are also able to predict a further hierarchy of new models that will emerge as data quality improves to better resolve the underlying continuity of animal movement. Finally, we also show that Langevin equations must obey a fluctuation-dissipation theorem to generate processes that fall from this class of maximum-entropy distributions when the constraints are purely kinematic.

  14. Pareto versus lognormal: a maximum entropy test.

    Science.gov (United States)

    Bee, Marco; Riccaboni, Massimo; Schiavo, Stefano

    2011-08-01

    It is commonly found that distributions that seem to be lognormal over a broad range change to a power-law (Pareto) distribution for the last few percentiles. The distributions of many physical, natural, and social events (earthquake size, species abundance, income and wealth, as well as file, city, and firm sizes) display this structure. We present a test for the occurrence of power-law tails in statistical distributions based on maximum entropy. This methodology allows one to identify the true data-generating processes even in the case when it is neither lognormal nor Pareto. The maximum entropy approach is then compared with other widely used methods and applied to different levels of aggregation of complex systems. Our results provide support for the theory that distributions with lognormal body and Pareto tail can be generated as mixtures of lognormally distributed units.

  15. Maximum likelihood estimation for integrated diffusion processes

    DEFF Research Database (Denmark)

    Baltazar-Larios, Fernando; Sørensen, Michael

    We propose a method for obtaining maximum likelihood estimates of parameters in diffusion models when the data is a discrete time sample of the integral of the process, while no direct observations of the process itself are available. The data are, moreover, assumed to be contaminated...... EM-algorithm to obtain maximum likelihood estimates of the parameters in the diffusion model. As part of the algorithm, we use a recent simple method for approximate simulation of diffusion bridges. In simulation studies for the Ornstein-Uhlenbeck process and the CIR process the proposed method works...... by measurement errors. Integrated volatility is an example of this type of observations. Another example is ice-core data on oxygen isotopes used to investigate paleo-temperatures. The data can be viewed as incomplete observations of a model with a tractable likelihood function. Therefore we propose a simulated...

  16. A Maximum Radius for Habitable Planets.

    Science.gov (United States)

    Alibert, Yann

    2015-09-01

    We compute the maximum radius a planet can have in order to fulfill two constraints that are likely necessary conditions for habitability: 1- surface temperature and pressure compatible with the existence of liquid water, and 2- no ice layer at the bottom of a putative global ocean, that would prevent the operation of the geologic carbon cycle to operate. We demonstrate that, above a given radius, these two constraints cannot be met: in the Super-Earth mass range (1-12 Mearth), the overall maximum that a planet can have varies between 1.8 and 2.3 Rearth. This radius is reduced when considering planets with higher Fe/Si ratios, and taking into account irradiation effects on the structure of the gas envelope.

  17. Maximum parsimony on subsets of taxa.

    Science.gov (United States)

    Fischer, Mareike; Thatte, Bhalchandra D

    2009-09-21

    In this paper we investigate mathematical questions concerning the reliability (reconstruction accuracy) of Fitch's maximum parsimony algorithm for reconstructing the ancestral state given a phylogenetic tree and a character. In particular, we consider the question whether the maximum parsimony method applied to a subset of taxa can reconstruct the ancestral state of the root more accurately than when applied to all taxa, and we give an example showing that this indeed is possible. A surprising feature of our example is that ignoring a taxon closer to the root improves the reliability of the method. On the other hand, in the case of the two-state symmetric substitution model, we answer affirmatively a conjecture of Li, Steel and Zhang which states that under a molecular clock the probability that the state at a single taxon is a correct guess of the ancestral state is a lower bound on the reconstruction accuracy of Fitch's method applied to all taxa.

  18. MIMO Radar Transmit Beampattern Design Without Synthesising the Covariance Matrix

    KAUST Repository

    Ahmed, Sajid

    2013-10-28

    Compared to phased-array, multiple-input multiple-output (MIMO) radars provide more degrees-offreedom (DOF) that can be exploited for improved spatial resolution, better parametric identifiability, lower side-lobe levels at the transmitter/receiver, and design variety of transmit beampatterns. The design of the transmit beampattern generally requires the waveforms to have arbitrary auto- and crosscorrelation properties. The generation of such waveforms is a two step complicated process. In the first step a waveform covariance matrix is synthesised, which is a constrained optimisation problem. In the second step, to realise this covariance matrix actual waveforms are designed, which is also a constrained optimisation problem. Our proposed scheme converts this two step constrained optimisation problem into a one step unconstrained optimisation problem. In the proposed scheme, in contrast to synthesising the covariance matrix for the desired beampattern, nT independent finite-alphabet constantenvelope waveforms are generated and pre-processed, with weight matrix W, before transmitting from the antennas. In this work, two weight matrices are proposed that can be easily optimised for the desired symmetric and non-symmetric beampatterns and guarantee equal average power transmission from each antenna. Simulation results validate our claims.

  19. Selective wave-transmitting electromagnetic absorber through composite metasurface

    Science.gov (United States)

    Sun, Zhiwei; Zhao, Junming; Zhu, Bo; Jiang, Tian; Feng, Yijun

    2017-11-01

    Selective wave-transmitting absorbers which have one or more narrow transmission bands inside a wide absorption band are often demanded in wireless communication and radome applications for reducing the coupling between different systems, improving anti-jamming capability, and reducing antennas' radar cross section. Here we propose a feasible method that utilizing composite of two metasurfaces with different polarization dependent characteristics, one works as electromagnetic polarization rotator and the other as a wideband polarization dependent electromagnetic wave absorber. The polarization rotator produces a cross polarization output in the wave-transmitting band, while preserves the polarization of the incidence outside the band. The metasurface absorber works for certain linear polarization with a much wider absorption band covering the wave-transmitting frequency. When combining these two metasurfaces properly, the whole structure behaves as a wideband absorber with a certain frequency transmission window. The proposal may be applied in radome designs to reduce the radar cross section of antenna or improving the electromagnetic compatibility in communication devices.

  20. Interaction of the tick immune system with transmitted pathogens

    Directory of Open Access Journals (Sweden)

    Ondrej eHajdusek

    2013-07-01

    Full Text Available Ticks are hematophagous arachnids transmitting a wide variety of pathogens including viruses, bacteria, and protozoans to their vertebrate hosts. The tick vector competence has to be intimately linked to the ability of transmitted pathogens to evade tick defense mechanisms encountered on their route through the tick body comprising midgut, hemolymph, salivary glands or ovaries. Tick innate immunity is, like in other invertebrates, based on an orchestrated action of humoral and cellular immune responses. The direct antimicrobial defense in ticks is accomplished by a variety of small molecules such as defensins, lysozymes or by tick-specific antimicrobial compounds such as microplusin/hebraein or 5.3-kDa family proteins. Phagocytosis of the invading microbes by tick hemocytes seems to be mediated by the primordial complement-like system composed of thioester-containing proteins, fibrinogen-related lectins and convertase-like factors. Moreover, an important role in survival of the ingested microbes seems to be played by host proteins and redox balance maintenance in the tick midgut. Here, we summarize recent knowledge about the major components of tick immune system and focus on their interaction with the relevant tick-transmitted pathogens, represented by spirochetes (Borrelia, rickettsiae (Anaplasma, and protozoans (Babesia. Availability of the tick genomic database and feasibility of functional genomics based on RNA interference greatly contribute to the understanding of molecular and cellular interplay at the tick-pathogen interface and may provide new targets for blocking the transmission of tick pathogens.

  1. Pair formation models for sexually transmitted infections: A primer

    Directory of Open Access Journals (Sweden)

    Mirjam Kretzschmar

    2017-08-01

    Full Text Available For modelling sexually transmitted infections, duration of partnerships can strongly influence the transmission dynamics of the infection. If partnerships are monogamous, pairs of susceptible individuals are protected from becoming infected, while pairs of infected individuals delay onward transmission of the infection as long as they persist. In addition, for curable infections re-infection from an infected partner may occur. Furthermore, interventions based on contact tracing rely on the possibility of identifying and treating partners of infected individuals. To reflect these features in a mathematical model, pair formation models were introduced to mathematical epidemiology in the 1980's. They have since been developed into a widely used tool in modelling sexually transmitted infections and the impact of interventions. Here we give a basic introduction to the concepts of pair formation models for a susceptible-infected-susceptible (SIS epidemic. We review some results and applications of pair formation models mainly in the context of chlamydia infection. Keywords: Pair formation, Mathematical model, Partnership duration, Sexually transmitted infections, Basic reproduction number

  2. Maximum entropy analysis of liquid diffraction data

    International Nuclear Information System (INIS)

    Root, J.H.; Egelstaff, P.A.; Nickel, B.G.

    1986-01-01

    A maximum entropy method for reducing truncation effects in the inverse Fourier transform of structure factor, S(q), to pair correlation function, g(r), is described. The advantages and limitations of the method are explored with the PY hard sphere structure factor as model input data. An example using real data on liquid chlorine, is then presented. It is seen that spurious structure is greatly reduced in comparison to traditional Fourier transform methods. (author)

  3. Evaluation of a fast single-photon avalanche photodiode for measurement of early transmitted photons through diffusive media.

    Science.gov (United States)

    Mu, Ying; Valim, Niksa; Niedre, Mark

    2013-06-15

    We tested the performance of a fast single-photon avalanche photodiode (SPAD) in measurement of early transmitted photons through diffusive media. In combination with a femtosecond titanium:sapphire laser, the overall instrument temporal response time was 59 ps. Using two experimental models, we showed that the SPAD allowed measurement of photon-density sensitivity functions that were approximately 65% narrower than the ungated continuous wave case at very early times. This exceeds the performance that we have previously achieved with photomultiplier-tube-based systems and approaches the theoretical maximum predicted by time-resolved Monte Carlo simulations.

  4. A Maximum Resonant Set of Polyomino Graphs

    Directory of Open Access Journals (Sweden)

    Zhang Heping

    2016-05-01

    Full Text Available A polyomino graph P is a connected finite subgraph of the infinite plane grid such that each finite face is surrounded by a regular square of side length one and each edge belongs to at least one square. A dimer covering of P corresponds to a perfect matching. Different dimer coverings can interact via an alternating cycle (or square with respect to them. A set of disjoint squares of P is a resonant set if P has a perfect matching M so that each one of those squares is M-alternating. In this paper, we show that if K is a maximum resonant set of P, then P − K has a unique perfect matching. We further prove that the maximum forcing number of a polyomino graph is equal to the cardinality of a maximum resonant set. This confirms a conjecture of Xu et al. [26]. We also show that if K is a maximal alternating set of P, then P − K has a unique perfect matching.

  5. Automatic maximum entropy spectral reconstruction in NMR

    International Nuclear Information System (INIS)

    Mobli, Mehdi; Maciejewski, Mark W.; Gryk, Michael R.; Hoch, Jeffrey C.

    2007-01-01

    Developments in superconducting magnets, cryogenic probes, isotope labeling strategies, and sophisticated pulse sequences together have enabled the application, in principle, of high-resolution NMR spectroscopy to biomolecular systems approaching 1 megadalton. In practice, however, conventional approaches to NMR that utilize the fast Fourier transform, which require data collected at uniform time intervals, result in prohibitively lengthy data collection times in order to achieve the full resolution afforded by high field magnets. A variety of approaches that involve nonuniform sampling have been proposed, each utilizing a non-Fourier method of spectrum analysis. A very general non-Fourier method that is capable of utilizing data collected using any of the proposed nonuniform sampling strategies is maximum entropy reconstruction. A limiting factor in the adoption of maximum entropy reconstruction in NMR has been the need to specify non-intuitive parameters. Here we describe a fully automated system for maximum entropy reconstruction that requires no user-specified parameters. A web-accessible script generator provides the user interface to the system

  6. maximum neutron flux at thermal nuclear reactors

    International Nuclear Information System (INIS)

    Strugar, P.

    1968-10-01

    Since actual research reactors are technically complicated and expensive facilities it is important to achieve savings by appropriate reactor lattice configurations. There is a number of papers, and practical examples of reactors with central reflector, dealing with spatial distribution of fuel elements which would result in higher neutron flux. Common disadvantage of all the solutions is that the choice of best solution is done starting from the anticipated spatial distributions of fuel elements. The weakness of these approaches is lack of defined optimization criteria. Direct approach is defined as follows: determine the spatial distribution of fuel concentration starting from the condition of maximum neutron flux by fulfilling the thermal constraints. Thus the problem of determining the maximum neutron flux is solving a variational problem which is beyond the possibilities of classical variational calculation. This variational problem has been successfully solved by applying the maximum principle of Pontrjagin. Optimum distribution of fuel concentration was obtained in explicit analytical form. Thus, spatial distribution of the neutron flux and critical dimensions of quite complex reactor system are calculated in a relatively simple way. In addition to the fact that the results are innovative this approach is interesting because of the optimization procedure itself [sr

  7. 20 CFR 10.806 - How are the maximum fees defined?

    Science.gov (United States)

    2010-04-01

    ... AMENDED Information for Medical Providers Medical Fee Schedule § 10.806 How are the maximum fees defined? For professional medical services, the Director shall maintain a schedule of maximum allowable fees.../Current Procedural Terminology (HCPCS/CPT) code which represents the relative skill, effort, risk and time...

  8. 30 CFR 77.902-1 - Fail safe ground check circuits; maximum voltage.

    Science.gov (United States)

    2010-07-01

    ... voltage. 77.902-1 Section 77.902-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... OF UNDERGROUND COAL MINES Low- and Medium-Voltage Alternating Current Circuits § 77.902-1 Fail safe ground check circuits; maximum voltage. The maximum voltage used for ground check circuits under § 77.902...

  9. On the maximum-entropy method for kinetic equation of radiation, particle and gas

    International Nuclear Information System (INIS)

    El-Wakil, S.A.; Madkour, M.A.; Degheidy, A.R.; Machali, H.M.

    1995-01-01

    The maximum-entropy approach is used to calculate some problems in radiative transfer and reactor physics such as the escape probability, the emergent and transmitted intensities for a finite slab as well as the emergent intensity for a semi-infinite medium. Also, it is employed to solve problems involving spherical geometry, such as luminosity (the total energy emitted by a sphere), neutron capture probability and the albedo problem. The technique is also employed in the kinetic theory of gases to calculate the Poiseuille flow and thermal creep of a rarefied gas between two plates. Numerical calculations are achieved and compared with the published data. The comparisons demonstrate that the maximum-entropy results are good in agreement with the exact ones. (orig.)

  10. Estimating Transmitted-Signal Phase Variations for Uplink Array Antennas

    Science.gov (United States)

    Paal, Leslie; Mukai, Ryan; Vilntrotter, Victor; Cornish, Timothy; Lee, Dennis

    2009-01-01

    A method of estimating phase drifts of microwave signals distributed to, and transmitted by, antennas in an array involves the use of the signals themselves as phase references. The method was conceived as part of the solution of the problem of maintaining precise phase calibration required for proper operation of an array of Deep Space Network (DSN) antennas on Earth used for communicating with distant spacecraft at frequencies between 7 and 8 GHz. The method could also be applied to purely terrestrial phased-array radar and other radio antenna array systems. In the DSN application, the electrical lengths (effective signal-propagation path lengths) of the various branches of the system for distributing the transmitted signals to the antennas are not precisely known, and they vary with time. The variations are attributable mostly to thermal expansion and contraction of fiber-optic and electrical signal cables and to a variety of causes associated with aging of signal-handling components. The variations are large enough to introduce large phase drifts at the signal frequency. It is necessary to measure and correct for these phase drifts in order to maintain phase calibration of the antennas. A prior method of measuring phase drifts involves the use of reference-frequency signals separate from the transmitted signals. A major impediment to accurate measurement of phase drifts over time by the prior method is the fact that although DSN reference-frequency sources separate from the transmitting signal sources are stable and accurate enough for most DSN purposes, they are not stable enough for use in maintaining phase calibrations, as required, to within a few degrees over times as long as days or possibly even weeks. By eliminating reliance on the reference-frequency subsystem, the present method overcomes this impediment. In a DSN array to which the present method applies (see figure), the microwave signals to be transmitted are generated by exciters in a signal

  11. Distributed maximum power point tracking in wind micro-grids

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Ramos-Paja

    2012-06-01

    Full Text Available With the aim of reducing the hardware requirements in micro-grids based on wind generators, a distributed maximum power point tracking algorithm is proposed. Such a solution reduces the amount of current sensors and processing devices to maximize the power extracted from the micro-grid, reducing the application cost. The analysis of the optimal operating points of the wind generator was performed experimentally, which in addition provides realistic model parameters. Finally, the proposed solution was validated by means of detailed simulations performed in the power electronics software PSIM, contrasting the achieved performance with traditional solutions.

  12. Global Harmonization of Maximum Residue Limits for Pesticides.

    Science.gov (United States)

    Ambrus, Árpád; Yang, Yong Zhen

    2016-01-13

    International trade plays an important role in national economics. The Codex Alimentarius Commission develops harmonized international food standards, guidelines, and codes of practice to protect the health of consumers and to ensure fair practices in the food trade. The Codex maximum residue limits (MRLs) elaborated by the Codex Committee on Pesticide Residues are based on the recommendations of the FAO/WHO Joint Meeting on Pesticides (JMPR). The basic principles applied currently by the JMPR for the evaluation of experimental data and related information are described together with some of the areas in which further developments are needed.

  13. Current Directions in Mediation Analysis

    Science.gov (United States)

    MacKinnon, David P.; Fairchild, Amanda J.

    2010-01-01

    Mediating variables continue to play an important role in psychological theory and research. A mediating variable transmits the effect of an antecedent variable on to a dependent variable, thereby providing more detailed understanding of relations among variables. Methods to assess mediation have been an active area of research for the last two decades. This paper describes the current state of methods to investigate mediating variables. PMID:20157637

  14. Current Directions in Mediation Analysis

    OpenAIRE

    MacKinnon, David P.; Fairchild, Amanda J.

    2009-01-01

    Mediating variables continue to play an important role in psychological theory and research. A mediating variable transmits the effect of an antecedent variable on to a dependent variable, thereby providing more detailed understanding of relations among variables. Methods to assess mediation have been an active area of research for the last two decades. This paper describes the current state of methods to investigate mediating variables.

  15. High performance monolithic power management system with dynamic maximum power point tracking for microbial fuel cells.

    Science.gov (United States)

    Erbay, Celal; Carreon-Bautista, Salvador; Sanchez-Sinencio, Edgar; Han, Arum

    2014-12-02

    Microbial fuel cell (MFC) that can directly generate electricity from organic waste or biomass is a promising renewable and clean technology. However, low power and low voltage output of MFCs typically do not allow directly operating most electrical applications, whether it is supplementing electricity to wastewater treatment plants or for powering autonomous wireless sensor networks. Power management systems (PMSs) can overcome this limitation by boosting the MFC output voltage and managing the power for maximum efficiency. We present a monolithic low-power-consuming PMS integrated circuit (IC) chip capable of dynamic maximum power point tracking (MPPT) to maximize the extracted power from MFCs, regardless of the power and voltage fluctuations from MFCs over time. The proposed PMS continuously detects the maximum power point (MPP) of the MFC and matches the load impedance of the PMS for maximum efficiency. The system also operates autonomously by directly drawing power from the MFC itself without any external power. The overall system efficiency, defined as the ratio between input energy from the MFC and output energy stored into the supercapacitor of the PMS, was 30%. As a demonstration, the PMS connected to a 240 mL two-chamber MFC (generating 0.4 V and 512 μW at MPP) successfully powered a wireless temperature sensor that requires a voltage of 2.5 V and consumes power of 85 mW each time it transmit the sensor data, and successfully transmitted a sensor reading every 7.5 min. The PMS also efficiently managed the power output of a lower-power producing MFC, demonstrating that the PMS works efficiently at various MFC power output level.

  16. On the diversity enhancement and power balancing of per-subcarrier transmit antenna selection in OFDM systems

    KAUST Repository

    Park, Kihong

    2011-01-01

    In this paper, we consider multicarrier systems with multiple transmit antennas under a power-balancing constraint. Applying transmit antenna selection and discrete rate-adaptive modulation using M-ary quadrature-amplitude modulation (QAM) according to the channel variation per subcarrier, we develop an optimal transmit antenna selection scheme in terms of the maximum spectral efficiency, where all the possible groupings for sending the same information-bearing signals in a group of subcarriers are searched, and the groups of subcarriers for providing the frequency diversity gain are formed. In addition, we propose a suboptimal method for reducing the computational complexity of the optimal method. The suboptimal scheme considers only the subcarriers under outage, and these subcarriers are sequentially combined until the required signal-to-noise ratio (SNR) is met. Numerical results show that the proposed suboptimal method with diversity combining outperforms the optimal antenna selection without diversity combining, as introduced in the work of Sandell and Coon, particularly for low-SNR regions, and offers the spectral efficiency close to the optimal method with diversity combining while maintaining lower complexity. © 2011 IEEE.

  17. Maximum entropy decomposition of quadrupole mass spectra

    International Nuclear Information System (INIS)

    Toussaint, U. von; Dose, V.; Golan, A.

    2004-01-01

    We present an information-theoretic method called generalized maximum entropy (GME) for decomposing mass spectra of gas mixtures from noisy measurements. In this GME approach to the noisy, underdetermined inverse problem, the joint entropies of concentration, cracking, and noise probabilities are maximized subject to the measured data. This provides a robust estimation for the unknown cracking patterns and the concentrations of the contributing molecules. The method is applied to mass spectroscopic data of hydrocarbons, and the estimates are compared with those received from a Bayesian approach. We show that the GME method is efficient and is computationally fast

  18. Maximum power operation of interacting molecular motors

    DEFF Research Database (Denmark)

    Golubeva, Natalia; Imparato, Alberto

    2013-01-01

    , as compared to the non-interacting system, in a wide range of biologically compatible scenarios. We furthermore consider the case where the motor-motor interaction directly affects the internal chemical cycle and investigate the effect on the system dynamics and thermodynamics.......We study the mechanical and thermodynamic properties of different traffic models for kinesin which are relevant in biological and experimental contexts. We find that motor-motor interactions play a fundamental role by enhancing the thermodynamic efficiency at maximum power of the motors...

  19. Maximum entropy method in momentum density reconstruction

    International Nuclear Information System (INIS)

    Dobrzynski, L.; Holas, A.

    1997-01-01

    The Maximum Entropy Method (MEM) is applied to the reconstruction of the 3-dimensional electron momentum density distributions observed through the set of Compton profiles measured along various crystallographic directions. It is shown that the reconstruction of electron momentum density may be reliably carried out with the aid of simple iterative algorithm suggested originally by Collins. A number of distributions has been simulated in order to check the performance of MEM. It is shown that MEM can be recommended as a model-free approach. (author). 13 refs, 1 fig

  20. On the maximum drawdown during speculative bubbles

    Science.gov (United States)

    Rotundo, Giulia; Navarra, Mauro

    2007-08-01

    A taxonomy of large financial crashes proposed in the literature locates the burst of speculative bubbles due to endogenous causes in the framework of extreme stock market crashes, defined as falls of market prices that are outlier with respect to the bulk of drawdown price movement distribution. This paper goes on deeper in the analysis providing a further characterization of the rising part of such selected bubbles through the examination of drawdown and maximum drawdown movement of indices prices. The analysis of drawdown duration is also performed and it is the core of the risk measure estimated here.

  1. Multi-Channel Maximum Likelihood Pitch Estimation

    DEFF Research Database (Denmark)

    Christensen, Mads Græsbøll

    2012-01-01

    In this paper, a method for multi-channel pitch estimation is proposed. The method is a maximum likelihood estimator and is based on a parametric model where the signals in the various channels share the same fundamental frequency but can have different amplitudes, phases, and noise characteristics....... This essentially means that the model allows for different conditions in the various channels, like different signal-to-noise ratios, microphone characteristics and reverberation. Moreover, the method does not assume that a certain array structure is used but rather relies on a more general model and is hence...

  2. Conductivity maximum in a charged colloidal suspension

    Energy Technology Data Exchange (ETDEWEB)

    Bastea, S

    2009-01-27

    Molecular dynamics simulations of a charged colloidal suspension in the salt-free regime show that the system exhibits an electrical conductivity maximum as a function of colloid charge. We attribute this behavior to two main competing effects: colloid effective charge saturation due to counterion 'condensation' and diffusion slowdown due to the relaxation effect. In agreement with previous observations, we also find that the effective transported charge is larger than the one determined by the Stern layer and suggest that it corresponds to the boundary fluid layer at the surface of the colloidal particles.

  3. Dynamical maximum entropy approach to flocking.

    Science.gov (United States)

    Cavagna, Andrea; Giardina, Irene; Ginelli, Francesco; Mora, Thierry; Piovani, Duccio; Tavarone, Raffaele; Walczak, Aleksandra M

    2014-04-01

    We derive a new method to infer from data the out-of-equilibrium alignment dynamics of collectively moving animal groups, by considering the maximum entropy model distribution consistent with temporal and spatial correlations of flight direction. When bird neighborhoods evolve rapidly, this dynamical inference correctly learns the parameters of the model, while a static one relying only on the spatial correlations fails. When neighbors change slowly and the detailed balance is satisfied, we recover the static procedure. We demonstrate the validity of the method on simulated data. The approach is applicable to other systems of active matter.

  4. Maximum Temperature Detection System for Integrated Circuits

    Science.gov (United States)

    Frankiewicz, Maciej; Kos, Andrzej

    2015-03-01

    The paper describes structure and measurement results of the system detecting present maximum temperature on the surface of an integrated circuit. The system consists of the set of proportional to absolute temperature sensors, temperature processing path and a digital part designed in VHDL. Analogue parts of the circuit where designed with full-custom technique. The system is a part of temperature-controlled oscillator circuit - a power management system based on dynamic frequency scaling method. The oscillator cooperates with microprocessor dedicated for thermal experiments. The whole system is implemented in UMC CMOS 0.18 μm (1.8 V) technology.

  5. Maximum entropy PDF projection: A review

    Science.gov (United States)

    Baggenstoss, Paul M.

    2017-06-01

    We review maximum entropy (MaxEnt) PDF projection, a method with wide potential applications in statistical inference. The method constructs a sampling distribution for a high-dimensional vector x based on knowing the sampling distribution p(z) of a lower-dimensional feature z = T (x). Under mild conditions, the distribution p(x) having highest possible entropy among all distributions consistent with p(z) may be readily found. Furthermore, the MaxEnt p(x) may be sampled, making the approach useful in Monte Carlo methods. We review the theorem and present a case study in model order selection and classification for handwritten character recognition.

  6. Multiperiod Maximum Loss is time unit invariant.

    Science.gov (United States)

    Kovacevic, Raimund M; Breuer, Thomas

    2016-01-01

    Time unit invariance is introduced as an additional requirement for multiperiod risk measures: for a constant portfolio under an i.i.d. risk factor process, the multiperiod risk should equal the one period risk of the aggregated loss, for an appropriate choice of parameters and independent of the portfolio and its distribution. Multiperiod Maximum Loss over a sequence of Kullback-Leibler balls is time unit invariant. This is also the case for the entropic risk measure. On the other hand, multiperiod Value at Risk and multiperiod Expected Shortfall are not time unit invariant.

  7. Ancestral sequence reconstruction with Maximum Parsimony

    OpenAIRE

    Herbst, Lina; Fischer, Mareike

    2017-01-01

    One of the main aims in phylogenetics is the estimation of ancestral sequences based on present-day data like, for instance, DNA alignments. One way to estimate the data of the last common ancestor of a given set of species is to first reconstruct a phylogenetic tree with some tree inference method and then to use some method of ancestral state inference based on that tree. One of the best-known methods both for tree inference as well as for ancestral sequence inference is Maximum Parsimony (...

  8. Prevalence of sexually transmitted infections and the sexual behavior of elderly people presenting to health examination centers in Korea.

    Science.gov (United States)

    Choe, Hyun-Sop; Lee, Seung-Ju; Kim, Chul Sung; Cho, Yong-Hyun

    2011-08-01

    Sexually transmitted infections are diseases provoking a great social and economic burden as well as health-related problems, and with the aging of society and the extension of life expectancy sexually transmitted infections in the elderly have drawn more attention these days. For the management of sexually transmitted infections in this population, basic epidemiological data need to be established. In this study, 1,804 persons from the general population aged over 60 years visiting health examination centers were tested for syphilis, gonorrhea, and chlamydia, and interviewed about the patterns of sexual behavior of elderly people through questionnaires. The prevalence rates of syphilis, gonorrhea, and chlamydia recorded were 0.222% (4/1804), 0 (none), and 0.776% (14/1804), respectively. The results of the survey showed that the sexual life of the elderly people was currently active, and the sexual behavior of chlamydia patients was distinguished in some characteristics from that of the general participants. Political management to prevent sexually transmitted infections needs to be continued in elderly people as it is in other age groups. More detailed follow-up studies are necessary to determine the incidence and prevalence rates of the diseases in the elderly population in future, and the results of this study are considered to be useful as basic data for such studies.

  9. Laser breakdown with millijoule trains of picosecond pulses transmitted through a hollow-core photonic-crystal fibre

    CERN Document Server

    Konorov, S O; Kolevatova, O A; Beloglasov, V I; Skibina, N B; Shcherbakov, A V; Wintner, E; Zheltikov, A M

    2003-01-01

    Sequences of picosecond pulses with a total energy in the pulse train of about 1 mJ are transmitted through a hollow-core photonic-crystal fibre with a core diameter of approximately 14 mu m. The fluence of laser radiation coupled into the core of the fibre under these conditions exceeds the breakdown threshold of fused silica by nearly an order of magnitude. The laser beam coming out of the fibre is then focused to produce a breakdown on a solid surface. Parameters of laser radiation were chosen in such a way as to avoid effects related to the excitation of higher order waveguide modes and ionization of the gas filling the fibre in order to provide the possibility to focus the output beam into a spot with a minimum diameter, thus ensuring the maximum spatial resolution and the maximum power density in the focal spot.

  10. Objective Bayesianism and the Maximum Entropy Principle

    Directory of Open Access Journals (Sweden)

    Jon Williamson

    2013-09-01

    Full Text Available Objective Bayesian epistemology invokes three norms: the strengths of our beliefs should be probabilities; they should be calibrated to our evidence of physical probabilities; and they should otherwise equivocate sufficiently between the basic propositions that we can express. The three norms are sometimes explicated by appealing to the maximum entropy principle, which says that a belief function should be a probability function, from all those that are calibrated to evidence, that has maximum entropy. However, the three norms of objective Bayesianism are usually justified in different ways. In this paper, we show that the three norms can all be subsumed under a single justification in terms of minimising worst-case expected loss. This, in turn, is equivalent to maximising a generalised notion of entropy. We suggest that requiring language invariance, in addition to minimising worst-case expected loss, motivates maximisation of standard entropy as opposed to maximisation of other instances of generalised entropy. Our argument also provides a qualified justification for updating degrees of belief by Bayesian conditionalisation. However, conditional probabilities play a less central part in the objective Bayesian account than they do under the subjective view of Bayesianism, leading to a reduced role for Bayes’ Theorem.

  11. Efficient heuristics for maximum common substructure search.

    Science.gov (United States)

    Englert, Péter; Kovács, Péter

    2015-05-26

    Maximum common substructure search is a computationally hard optimization problem with diverse applications in the field of cheminformatics, including similarity search, lead optimization, molecule alignment, and clustering. Most of these applications have strict constraints on running time, so heuristic methods are often preferred. However, the development of an algorithm that is both fast enough and accurate enough for most practical purposes is still a challenge. Moreover, in some applications, the quality of a common substructure depends not only on its size but also on various topological features of the one-to-one atom correspondence it defines. Two state-of-the-art heuristic algorithms for finding maximum common substructures have been implemented at ChemAxon Ltd., and effective heuristics have been developed to improve both their efficiency and the relevance of the atom mappings they provide. The implementations have been thoroughly evaluated and compared with existing solutions (KCOMBU and Indigo). The heuristics have been found to greatly improve the performance and applicability of the algorithms. The purpose of this paper is to introduce the applied methods and present the experimental results.

  12. Direct maximum parsimony phylogeny reconstruction from genotype data

    Directory of Open Access Journals (Sweden)

    Ravi R

    2007-12-01

    Full Text Available Abstract Background Maximum parsimony phylogenetic tree reconstruction from genetic variation data is a fundamental problem in computational genetics with many practical applications in population genetics, whole genome analysis, and the search for genetic predictors of disease. Efficient methods are available for reconstruction of maximum parsimony trees from haplotype data, but such data are difficult to determine directly for autosomal DNA. Data more commonly is available in the form of genotypes, which consist of conflated combinations of pairs of haplotypes from homologous chromosomes. Currently, there are no general algorithms for the direct reconstruction of maximum parsimony phylogenies from genotype data. Hence phylogenetic applications for autosomal data must therefore rely on other methods for first computationally inferring haplotypes from genotypes. Results In this work, we develop the first practical method for computing maximum parsimony phylogenies directly from genotype data. We show that the standard practice of first inferring haplotypes from genotypes and then reconstructing a phylogeny on the haplotypes often substantially overestimates phylogeny size. As an immediate application, our method can be used to determine the minimum number of mutations required to explain a given set of observed genotypes. Conclusion Phylogeny reconstruction directly from unphased data is computationally feasible for moderate-sized problem instances and can lead to substantially more accurate tree size inferences than the standard practice of treating phasing and phylogeny construction as two separate analysis stages. The difference between the approaches is particularly important for downstream applications that require a lower-bound on the number of mutations that the genetic region has undergone.

  13. A Hybrid Maximum Power Point Search Method Using Temperature Measurements in Partial Shading Conditions

    Directory of Open Access Journals (Sweden)

    Mroczka Janusz

    2014-12-01

    Full Text Available Photovoltaic panels have a non-linear current-voltage characteristics to produce the maximum power at only one point called the maximum power point. In the case of the uniform illumination a single solar panel shows only one maximum power, which is also the global maximum power point. In the case an irregularly illuminated photovoltaic panel many local maxima on the power-voltage curve can be observed and only one of them is the global maximum. The proposed algorithm detects whether a solar panel is in the uniform insolation conditions. Then an appropriate strategy of tracking the maximum power point is taken using a decision algorithm. The proposed method is simulated in the environment created by the authors, which allows to stimulate photovoltaic panels in real conditions of lighting, temperature and shading.

  14. Quantitative Estimation of Transmitted and Reflected Lamb Waves at Discontinuity

    International Nuclear Information System (INIS)

    Lim, Hyung Jin; Sohn, Hoon

    2010-01-01

    For the application of Lamb wave to structural health monitoring(SHM), understanding its physical characteristic and interaction between Lamb wave and defect of the host structure is an important issue. In this study, reflected, transmitted and mode converted Lamb waves at discontinuity of a plate structure were simulated and the amplitude ratios are calculated theoretically using Modal decomposition method. The predicted results were verified comparing with finite element method(FEM) and experimental results simulating attached PZTs. The result shows that the theoretical prediction is close to the FEM and the experimental verification. Moreover, quantitative estimation method was suggested using amplitude ratio of Lamb wave at discontinuity

  15. Ray-map migration of transmitted surface waves

    KAUST Repository

    Li, Jing

    2016-08-25

    Near-surface normal faults can sometimes separate two distinct zones of velocity heterogeneity, where the medium on one side of the fault has a faster velocity than on the other side. Therefore, the slope of surface-wave arrivals in a common-shot gather should abruptly change near the surface projection of the fault. We present ray-map imaging method that migrates transmitted surface waves to the fault plane, and therefore it roughly estimates the orientation, depth, and location of the near-surface fault. The main benefits of this method are that it is computationally inexpensive and robust in the presence of noise.

  16. Venereal worms: sexually transmitted nematodes in the decorated cricket.

    Science.gov (United States)

    Luong, L T; Platzer, E G; Zuk, M; Giblin-Davis, R M

    2000-06-01

    The nematode, Mehdinema alii, occurs in the alimentary canal of the decorated cricket Gryllodes sigillatus. Adult nematodes occur primarily in the hindgut of mature male crickets, whereas juvenile nematodes are found in the genital chambers of mature male and female crickets. Here, we present experimental evidence for the venereal transmission of M. alii in G. sigillatus. Infectivity experiments were conducted to test for transmission via oral-fecal contamination, same-sex contact, and copulation. The infective dauers of the nematode are transferred from male to female crickets during copulation. Adult female crickets harboring infective dauers subsequently transfer the nematode to their next mates. Thus, M. alii is transmitted sexually during copulation.

  17. Counterfactual quantum cloning without transmitting any physical particles

    Science.gov (United States)

    Guo, Qi; Zhai, Shuqin; Cheng, Liu-Yong; Wang, Hong-Fu; Zhang, Shou

    2017-11-01

    We propose a counterfactual 1 →2 economical phase-covariant cloning scheme. Compared with the existing protocols using flying qubits, the main difference of the presented scheme is that the cloning can be achieved without transmitting the photon between the two parties. In addition, this counterfactual scheme does not need to construct controlled quantum gates to perform joint logical operations between the cloned qubit and the blank copy. We also numerically evaluate the performance of the present scheme in the practical experiment, which shows this cloning scheme can be implemented with a high success of probability and the fidelity is close to the optimal value in the ideal asymptotic limit.

  18. The value transmitted by woman in Disney animated films

    Directory of Open Access Journals (Sweden)

    Verónica Marín Díaz

    2017-09-01

    Full Text Available The animated films, has taken in the last decade of great relevance. This study aims to analyse the values that the female of the films from Disney. Through a descriptive and correlational study, we have proceeded to consult a group of teachers (N = 27 of said educational level, through a questionnaire of Marin and Sanchez (2015. The main result achieved has been the realization of the development of women and their role in society. It has also been confirmed that all transmit at least one traditional socially accepted value.

  19. Sexually transmitted diseases and HIV. A female perspective.

    LENUS (Irish Health Repository)

    Horgan, M

    2012-02-03

    Sexually transmitted diseases have the greatest impact on the health of women. They are frequently asymptomatic, so screening for infection is important in preventing the long-term sequelae which include infertility, ectopic pregnancy, and chronic pelvic pain. HIV continues to increase in the female population and the gynecologic complications associated with it are unique to this population. Use of zidovudine in pregnant HIV-infected women has substantially decreased the rate of vertical transmission of HIV infection. The epidemiologic synergy between HIV and STDs is well recognized and prevention of one is dependent on prevention of the other.

  20. United States Climate Reference Network (USCRN) Raw Data Transmitted from Satellite

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — USCRN Raw Transmitted Data is level 0 data received from the USCRN stations that are transmitted continuously. The data values are ingested with a unique 18-bit...

  1. Comparisons of receive array interference reduction techniques under erroneous generalized transmit beamforming

    KAUST Repository

    Radaydeh, Redha Mahmoud; Alouini, Mohamed-Slim

    2014-01-01

    information for the desired user spatially uncorrelated transmit channels on the effectiveness of transmit beamforming for different interference reduction techniques is investigated. The case of over-loaded receive array with closely-spaced elements

  2. 75 FR 79006 - Submission for OMB Review; Comment Request; Transfusion-Transmitted Retrovirus and Hepatitis...

    Science.gov (United States)

    2010-12-17

    ... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health Submission for OMB Review; Comment Request; Transfusion- Transmitted Retrovirus and Hepatitis Virus Rates and Risk Factors: Improving... control number. Proposed Collection: Title: Transfusion-transmitted retrovirus and hepatitis virus rates...

  3. Maximum Entropy Closure of Balance Equations for Miniband Semiconductor Superlattices

    Directory of Open Access Journals (Sweden)

    Luis L. Bonilla

    2016-07-01

    Full Text Available Charge transport in nanosized electronic systems is described by semiclassical or quantum kinetic equations that are often costly to solve numerically and difficult to reduce systematically to macroscopic balance equations for densities, currents, temperatures and other moments of macroscopic variables. The maximum entropy principle can be used to close the system of equations for the moments but its accuracy or range of validity are not always clear. In this paper, we compare numerical solutions of balance equations for nonlinear electron transport in semiconductor superlattices. The equations have been obtained from Boltzmann–Poisson kinetic equations very far from equilibrium for strong fields, either by the maximum entropy principle or by a systematic Chapman–Enskog perturbation procedure. Both approaches produce the same current-voltage characteristic curve for uniform fields. When the superlattices are DC voltage biased in a region where there are stable time periodic solutions corresponding to recycling and motion of electric field pulses, the differences between the numerical solutions produced by numerically solving both types of balance equations are smaller than the expansion parameter used in the perturbation procedure. These results and possible new research venues are discussed.

  4. Hydraulic Limits on Maximum Plant Transpiration

    Science.gov (United States)

    Manzoni, S.; Vico, G.; Katul, G. G.; Palmroth, S.; Jackson, R. B.; Porporato, A. M.

    2011-12-01

    Photosynthesis occurs at the expense of water losses through transpiration. As a consequence of this basic carbon-water interaction at the leaf level, plant growth and ecosystem carbon exchanges are tightly coupled to transpiration. In this contribution, the hydraulic constraints that limit transpiration rates under well-watered conditions are examined across plant functional types and climates. The potential water flow through plants is proportional to both xylem hydraulic conductivity (which depends on plant carbon economy) and the difference in water potential between the soil and the atmosphere (the driving force that pulls water from the soil). Differently from previous works, we study how this potential flux changes with the amplitude of the driving force (i.e., we focus on xylem properties and not on stomatal regulation). Xylem hydraulic conductivity decreases as the driving force increases due to cavitation of the tissues. As a result of this negative feedback, more negative leaf (and xylem) water potentials would provide a stronger driving force for water transport, while at the same time limiting xylem hydraulic conductivity due to cavitation. Here, the leaf water potential value that allows an optimum balance between driving force and xylem conductivity is quantified, thus defining the maximum transpiration rate that can be sustained by the soil-to-leaf hydraulic system. To apply the proposed framework at the global scale, a novel database of xylem conductivity and cavitation vulnerability across plant types and biomes is developed. Conductivity and water potential at 50% cavitation are shown to be complementary (in particular between angiosperms and conifers), suggesting a tradeoff between transport efficiency and hydraulic safety. Plants from warmer and drier biomes tend to achieve larger maximum transpiration than plants growing in environments with lower atmospheric water demand. The predicted maximum transpiration and the corresponding leaf water

  5. Analogue of Pontryagin's maximum principle for multiple integrals minimization problems

    OpenAIRE

    Mikhail, Zelikin

    2016-01-01

    The theorem like Pontryagin's maximum principle for multiple integrals is proved. Unlike the usual maximum principle, the maximum should be taken not over all matrices, but only on matrices of rank one. Examples are given.

  6. Lake Basin Fetch and Maximum Length/Width

    Data.gov (United States)

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake polygon...

  7. Maximum Likelihood Reconstruction for Magnetic Resonance Fingerprinting.

    Science.gov (United States)

    Zhao, Bo; Setsompop, Kawin; Ye, Huihui; Cauley, Stephen F; Wald, Lawrence L

    2016-08-01

    This paper introduces a statistical estimation framework for magnetic resonance (MR) fingerprinting, a recently proposed quantitative imaging paradigm. Within this framework, we present a maximum likelihood (ML) formalism to estimate multiple MR tissue parameter maps directly from highly undersampled, noisy k-space data. A novel algorithm, based on variable splitting, the alternating direction method of multipliers, and the variable projection method, is developed to solve the resulting optimization problem. Representative results from both simulations and in vivo experiments demonstrate that the proposed approach yields significantly improved accuracy in parameter estimation, compared to the conventional MR fingerprinting reconstruction. Moreover, the proposed framework provides new theoretical insights into the conventional approach. We show analytically that the conventional approach is an approximation to the ML reconstruction; more precisely, it is exactly equivalent to the first iteration of the proposed algorithm for the ML reconstruction, provided that a gridding reconstruction is used as an initialization.

  8. Maximum Profit Configurations of Commercial Engines

    Directory of Open Access Journals (Sweden)

    Yiran Chen

    2011-06-01

    Full Text Available An investigation of commercial engines with finite capacity low- and high-price economic subsystems and a generalized commodity transfer law [n ∝ Δ (P m] in commodity flow processes, in which effects of the price elasticities of supply and demand are introduced, is presented in this paper. Optimal cycle configurations of commercial engines for maximum profit are obtained by applying optimal control theory. In some special cases, the eventual state—market equilibrium—is solely determined by the initial conditions and the inherent characteristics of two subsystems; while the different ways of transfer affect the model in respects of the specific forms of the paths of prices and the instantaneous commodity flow, i.e., the optimal configuration.

  9. The worst case complexity of maximum parsimony.

    Science.gov (United States)

    Carmel, Amir; Musa-Lempel, Noa; Tsur, Dekel; Ziv-Ukelson, Michal

    2014-11-01

    One of the core classical problems in computational biology is that of constructing the most parsimonious phylogenetic tree interpreting an input set of sequences from the genomes of evolutionarily related organisms. We reexamine the classical maximum parsimony (MP) optimization problem for the general (asymmetric) scoring matrix case, where rooted phylogenies are implied, and analyze the worst case bounds of three approaches to MP: The approach of Cavalli-Sforza and Edwards, the approach of Hendy and Penny, and a new agglomerative, "bottom-up" approach we present in this article. We show that the second and third approaches are faster than the first one by a factor of Θ(√n) and Θ(n), respectively, where n is the number of species.

  10. Omnidirectional Wireless Power Transfer System Based on Rotary Transmitting Coil for Household Appliances

    Directory of Open Access Journals (Sweden)

    Gongjun Liu

    2018-04-01

    Full Text Available An omnidirectional magnetically coupled resonant wireless power transfer (WPT system based on rotary transmitting coil is presented. The proposed scheme can ease the variations of the transfer efficiency and output power caused by the deviation of transfer direction, and improve the unbalanced power distribution phenomenon between the receivers, which are still not fully achieved in current WPT systems. The modified coupled-mode model is built first to describe the non-rotary multi-receiver WPT system. The analysis indicates that the transfer efficiency and output power of the system can be expressed as functions of the deviation angle between the transmitting coil and receiving coil, which has a non-negligible influence on the system performances. Then, the modified high order coupled-mode model containing time-varying parameters about the deviation angle is derived for the proposed omnidirectional WPT system. Theoretical analysis and simulated results indicate that this system can transfer power to multiple receivers around the transmitter synchronously and evenly, which is very suitable for wireless charging for household appliances indoors. The scheme feasibility and theoretical analysis are verified by experimental results.

  11. The ecology and epidemiology of whitefly-transmitted viruses in Latin America.

    Science.gov (United States)

    Morales, Francisco J; Jones, Peter G

    2004-03-01

    Whitefly-transmitted geminiviruses are the most important constraint to the production of common bean and vegetable crops in the tropical lowlands and mid-altitude valleys of Latin America. Currently, over 30 distinct species of geminiviruses that are transmitted by the whitefly Bemisia tabaci infect common bean, tomato, pepper, cucurbits and other horticultural crops. A climate probability model (using FloraMap) was obtained using data from 304 geo-referenced locations where B. tabaci and geminiviruses cause significant damage. Clustering of the 304 points produced a simple model with two climatic variables: a dry season of at least 4 months each with less than 80 mm of rain and a mean temperature of the hottest month exceeding 21 degrees C. A modified Koeppen climate classification showed that 55% of the geminivirus-affected localities are in the tropical wet/dry region, 22% in the tropical and subtropical dry/humid climates and the remaining locations belonged to the wet equatorial and trade wind litoral climates. These findings contribute to understanding whitefly/geminivirus epidemics and implementation of sustainable integrated pest and disease management practices.

  12. Selection of unadapted, pathogenic SHIVs encoding newly transmitted HIV-1 envelope proteins.

    Science.gov (United States)

    Del Prete, Gregory Q; Ailers, Braiden; Moldt, Brian; Keele, Brandon F; Estes, Jacob D; Rodriguez, Anthony; Sampias, Marissa; Oswald, Kelli; Fast, Randy; Trubey, Charles M; Chertova, Elena; Smedley, Jeremy; LaBranche, Celia C; Montefiori, David C; Burton, Dennis R; Shaw, George M; Markowitz, Marty; Piatak, Michael; KewalRamani, Vineet N; Bieniasz, Paul D; Lifson, Jeffrey D; Hatziioannou, Theodora

    2014-09-10

    Infection of macaques with chimeric viruses based on SIVMAC but expressing the HIV-1 envelope (Env) glycoproteins (SHIVs) remains the most powerful model for evaluating prevention and therapeutic strategies against AIDS. Unfortunately, only a few SHIVs are currently available. Furthermore, their generation has required extensive adaptation of the HIV-1 Env sequences in macaques so they may not accurately represent HIV-1 Env proteins circulating in humans, potentially limiting their translational utility. We developed a strategy for generating large numbers of SHIV constructs expressing Env proteins from newly transmitted HIV-1 strains. By inoculating macaques with cocktails of multiple SHIV variants, we selected SHIVs that can replicate and cause AIDS-like disease in immunologically intact rhesus macaques without requiring animal-to-animal passage. One of these SHIVs could be transmitted mucosally. We demonstrate the utility of the SHIVs generated by this method for evaluating neutralizing antibody administration as a protection against mucosal SHIV challenge. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Modelling maximum likelihood estimation of availability

    International Nuclear Information System (INIS)

    Waller, R.A.; Tietjen, G.L.; Rock, G.W.

    1975-01-01

    Suppose the performance of a nuclear powered electrical generating power plant is continuously monitored to record the sequence of failure and repairs during sustained operation. The purpose of this study is to assess one method of estimating the performance of the power plant when the measure of performance is availability. That is, we determine the probability that the plant is operational at time t. To study the availability of a power plant, we first assume statistical models for the variables, X and Y, which denote the time-to-failure and the time-to-repair variables, respectively. Once those statistical models are specified, the availability, A(t), can be expressed as a function of some or all of their parameters. Usually those parameters are unknown in practice and so A(t) is unknown. This paper discusses the maximum likelihood estimator of A(t) when the time-to-failure model for X is an exponential density with parameter, lambda, and the time-to-repair model for Y is an exponential density with parameter, theta. Under the assumption of exponential models for X and Y, it follows that the instantaneous availability at time t is A(t)=lambda/(lambda+theta)+theta/(lambda+theta)exp[-[(1/lambda)+(1/theta)]t] with t>0. Also, the steady-state availability is A(infinity)=lambda/(lambda+theta). We use the observations from n failure-repair cycles of the power plant, say X 1 , X 2 , ..., Xsub(n), Y 1 , Y 2 , ..., Ysub(n) to present the maximum likelihood estimators of A(t) and A(infinity). The exact sampling distributions for those estimators and some statistical properties are discussed before a simulation model is used to determine 95% simulation intervals for A(t). The methodology is applied to two examples which approximate the operating history of two nuclear power plants. (author)

  14. The capacity to transmit classical information via black holes

    Science.gov (United States)

    Adami, Christoph; Ver Steeg, Greg

    2013-03-01

    One of the most vexing problems in theoretical physics is the relationship between quantum mechanics and gravity. According to an argument originally by Hawking, a black hole must destroy any information that is incident on it because the only radiation that a black hole releases during its evaporation (the Hawking radiation) is precisely thermal. Surprisingly, this claim has never been investigated within a quantum information-theoretic framework, where the black hole is treated as a quantum channel to transmit classical information. We calculate the capacity of the quantum black hole channel to transmit classical information (the Holevo capacity) within curved-space quantum field theory, and show that the information carried by late-time particles sent into a black hole can be recovered with arbitrary accuracy, from the signature left behind by the stimulated emission of radiation that must accompany any absorption event. We also show that this stimulated emission turns the black hole into an almost-optimal quantum cloning machine, where the violation of the no-cloning theorem is ensured by the noise provided by the Hawking radiation. Thus, rather than threatening the consistency of theoretical physics, Hawking radiation manages to save it instead.

  15. General aspects concerning strictly meat and fish transmitted parasitic infections

    Directory of Open Access Journals (Sweden)

    Daniele Crotti

    2012-03-01

    Full Text Available All helminths parasitosis transmitted to humans trough ingestion of infested fleshes, where man is definitive host too, are represented by four groups of helminths: the cestodes Dyphyllobothrium spp and Spirometra spp. (Sparganum proliferum is the name of the immature plerocercoid larva, the trematodes Opisthorchis Clonorchis “group” (many could be the genera and species involved, and the nematode Capillaria philippinensis. So, for fishes humans foods (fresh or salted water the control and prevention in veterinary health must be directed to investigation regarding intermediate stages of these parasites in fishes for human alimentation; if present, they must be eliminated. The helminths parasitosis transmitted to humans trough ingestion of infected mammals meats, are represented by taeniasis (Taenia saginata, T. solium and T. saginata asiatica, where man id definitive host and the infection is caused by ingestion of bovine or swine meat, containing larvae of these cestodes, and by trichinellosis, where humans represent a intermediate stage, and the eventual pathology is caused as by adult (acute infection as by larvae (chronic infection of this nematode: usually the meats responsible are infected pork, wild pork or horse (Trichinella spp. Is inside the meats of these animals. So the veterinary control and prophylaxis are necessary to avoid this disease and preventing the infection that could be severe.

  16. Indigenous Healers’ beliefs and practices concerning sexually transmitted diseases

    Directory of Open Access Journals (Sweden)

    FM Mulaudzi

    2006-09-01

    Full Text Available A Grounded Theory study has been used, based on its Theory of Symbolic Interactionism, to explore indigenous healers’ beliefs and practices concerning sexually transmitted diseases amongst the Vhavenda. Initial data collection has been done, using purposive sampling and when categories started emerging, theoretical sampling was then used. Data were analysed by using three basic types of coding namely, open coding, axial coding and selective coding. The findings of the study revealed a variety of terms used to identify STDs. It then also became evident that there are similarities between gonorrhoea, syphilis and condylomata as shown in the orthodox Sexually transmitted diseases posters used in orthodox medicine with some of the STDs that the indigenous healers are familiar with. In accordance with the Grounded Theory, the description of types of diseases, disease patterns as well as signs and symptoms culminated in the emergence of the Dirt Theory. Based on the above findings, it was recommended that guidelines for designing a module for teaching health professionals be formulated to assist nurses in understanding the beliefs and practices of the people they serve.

  17. Narrative Review: Sexually Transmitted Diseases and Homeless Youth-What Do We Know About Sexually Transmitted Disease Prevalence and Risk?

    Science.gov (United States)

    Caccamo, Alexandra; Kachur, Rachel; Williams, Samantha P

    2017-08-01

    Homelessness affects an estimated 1.6 million US youth annually. Compared with housed youth, homeless youth are more likely to engage in high-risk behaviors, including inconsistent condom use, multiple sex partners, survival sex, and alcohol/drug use, putting them at increased sexually transmitted disease (STD) risk. However, there is no national estimate of STD prevalence among this population. We identified 10 peer-reviewed articles (9 unique studies) reporting STD prevalence among homeless US youth (2000-2015). Descriptive and qualitative analyses identified STD prevalence ranges and risk factors among youth. Eight studies reported specific STD prevalence estimates, mainly chlamydia, gonorrhea, and syphilis. Overall STD prevalence among homeless youth ranged from 6% to 32%. STD rates for girls varied from 16.7% to 46%, and from 9% to 13.1% in boys. Most studies were conducted in the Western United States, with no studies from the Southeast or Northeast. Youths who experienced longer periods of homelessness were more likely to engage in high-risk sexual behaviors. Girls had lower rates of condom use and higher rates of STDs; boys were more likely to engage in anal and anonymous sex. Additionally, peer social networks contributed to protective effects on individual sexual risk behavior. Sexually transmitted disease prevalence estimates among homeless youth fluctuated greatly by study. Sexually transmitted disease risk behaviors are associated with unmet survival needs, length of homelessness, and influence of social networks. To promote sexual health and reduce STD rates, we need better estimates of STD prevalence, more geographic diversity of studies, and interventions addressing the behavioral associations identified in our review.

  18. A maximum power point tracking algorithm for photovoltaic applications

    Science.gov (United States)

    Nelatury, Sudarshan R.; Gray, Robert

    2013-05-01

    The voltage and current characteristic of a photovoltaic (PV) cell is highly nonlinear and operating a PV cell for maximum power transfer has been a challenge for a long time. Several techniques have been proposed to estimate and track the maximum power point (MPP) in order to improve the overall efficiency of a PV panel. A strategic use of the mean value theorem permits obtaining an analytical expression for a point that lies in a close neighborhood of the true MPP. But hitherto, an exact solution in closed form for the MPP is not published. This problem can be formulated analytically as a constrained optimization, which can be solved using the Lagrange method. This method results in a system of simultaneous nonlinear equations. Solving them directly is quite difficult. However, we can employ a recursive algorithm to yield a reasonably good solution. In graphical terms, suppose the voltage current characteristic and the constant power contours are plotted on the same voltage current plane, the point of tangency between the device characteristic and the constant power contours is the sought for MPP. It is subject to change with the incident irradiation and temperature and hence the algorithm that attempts to maintain the MPP should be adaptive in nature and is supposed to have fast convergence and the least misadjustment. There are two parts in its implementation. First, one needs to estimate the MPP. The second task is to have a DC-DC converter to match the given load to the MPP thus obtained. Availability of power electronics circuits made it possible to design efficient converters. In this paper although we do not show the results from a real circuit, we use MATLAB to obtain the MPP and a buck-boost converter to match the load. Under varying conditions of load resistance and irradiance we demonstrate MPP tracking in case of a commercially available solar panel MSX-60. The power electronics circuit is simulated by PSIM software.

  19. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Science.gov (United States)

    Rosario, Karyna; Capobianco, Heather; Ng, Terry Fei Fan; Breitbart, Mya; Polston, Jane E

    2014-01-01

    Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida) (genus Carlavirus) in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  20. RNA viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in North America.

    Directory of Open Access Journals (Sweden)

    Karyna Rosario

    Full Text Available Whiteflies from the Bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. Although whiteflies are known to transmit both DNA and RNA viruses, most of the diversity has been recorded for the former, specifically for the Begomovirus genus. This study investigated the total diversity of DNA and RNA viruses found in whiteflies collected from a single site in Florida to evaluate if there are additional, previously undetected viral types within the B. tabaci vector. Metagenomic analysis of viral DNA extracted from the whiteflies only resulted in the detection of begomoviruses. In contrast, whiteflies contained sequences similar to RNA viruses from divergent groups, with a diversity that extends beyond currently described viruses. The metagenomic analysis of whiteflies also led to the first report of a whitefly-transmitted RNA virus similar to Cowpea mild mottle virus (CpMMV Florida (genus Carlavirus in North America. Further investigation resulted in the detection of CpMMV Florida in native and cultivated plants growing near the original field site of whitefly collection and determination of its experimental host range. Analysis of complete CpMMV Florida genomes recovered from whiteflies and plants suggests that the current classification criteria for carlaviruses need to be reevaluated. Overall, metagenomic analysis supports that DNA plant viruses carried by B. tabaci are dominated by begomoviruses, whereas significantly less is known about RNA viruses present in this damaging insect vector.

  1. Maximum mass of magnetic white dwarfs

    International Nuclear Information System (INIS)

    Paret, Daryel Manreza; Horvath, Jorge Ernesto; Martínez, Aurora Perez

    2015-01-01

    We revisit the problem of the maximum masses of magnetized white dwarfs (WDs). The impact of a strong magnetic field on the structure equations is addressed. The pressures become anisotropic due to the presence of the magnetic field and split into parallel and perpendicular components. We first construct stable solutions of the Tolman-Oppenheimer-Volkoff equations for parallel pressures and find that physical solutions vanish for the perpendicular pressure when B ≳ 10 13 G. This fact establishes an upper bound for a magnetic field and the stability of the configurations in the (quasi) spherical approximation. Our findings also indicate that it is not possible to obtain stable magnetized WDs with super-Chandrasekhar masses because the values of the magnetic field needed for them are higher than this bound. To proceed into the anisotropic regime, we can apply results for structure equations appropriate for a cylindrical metric with anisotropic pressures that were derived in our previous work. From the solutions of the structure equations in cylindrical symmetry we have confirmed the same bound for B ∼ 10 13 G, since beyond this value no physical solutions are possible. Our tentative conclusion is that massive WDs with masses well beyond the Chandrasekhar limit do not constitute stable solutions and should not exist. (paper)

  2. TRENDS IN ESTIMATED MIXING DEPTH DAILY MAXIMUMS

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, R; Amy DuPont, A; Robert Kurzeja, R; Matt Parker, M

    2007-11-12

    Mixing depth is an important quantity in the determination of air pollution concentrations. Fireweather forecasts depend strongly on estimates of the mixing depth as a means of determining the altitude and dilution (ventilation rates) of smoke plumes. The Savannah River United States Forest Service (USFS) routinely conducts prescribed fires at the Savannah River Site (SRS), a heavily wooded Department of Energy (DOE) facility located in southwest South Carolina. For many years, the Savannah River National Laboratory (SRNL) has provided forecasts of weather conditions in support of the fire program, including an estimated mixing depth using potential temperature and turbulence change with height at a given location. This paper examines trends in the average estimated mixing depth daily maximum at the SRS over an extended period of time (4.75 years) derived from numerical atmospheric simulations using two versions of the Regional Atmospheric Modeling System (RAMS). This allows for differences to be seen between the model versions, as well as trends on a multi-year time frame. In addition, comparisons of predicted mixing depth for individual days in which special balloon soundings were released are also discussed.

  3. Mammographic image restoration using maximum entropy deconvolution

    International Nuclear Information System (INIS)

    Jannetta, A; Jackson, J C; Kotre, C J; Birch, I P; Robson, K J; Padgett, R

    2004-01-01

    An image restoration approach based on a Bayesian maximum entropy method (MEM) has been applied to a radiological image deconvolution problem, that of reduction of geometric blurring in magnification mammography. The aim of the work is to demonstrate an improvement in image spatial resolution in realistic noisy radiological images with no associated penalty in terms of reduction in the signal-to-noise ratio perceived by the observer. Images of the TORMAM mammographic image quality phantom were recorded using the standard magnification settings of 1.8 magnification/fine focus and also at 1.8 magnification/broad focus and 3.0 magnification/fine focus; the latter two arrangements would normally give rise to unacceptable geometric blurring. Measured point-spread functions were used in conjunction with the MEM image processing to de-blur these images. The results are presented as comparative images of phantom test features and as observer scores for the raw and processed images. Visualization of high resolution features and the total image scores for the test phantom were improved by the application of the MEM processing. It is argued that this successful demonstration of image de-blurring in noisy radiological images offers the possibility of weakening the link between focal spot size and geometric blurring in radiology, thus opening up new approaches to system optimization

  4. Maximum Margin Clustering of Hyperspectral Data

    Science.gov (United States)

    Niazmardi, S.; Safari, A.; Homayouni, S.

    2013-09-01

    In recent decades, large margin methods such as Support Vector Machines (SVMs) are supposed to be the state-of-the-art of supervised learning methods for classification of hyperspectral data. However, the results of these algorithms mainly depend on the quality and quantity of available training data. To tackle down the problems associated with the training data, the researcher put effort into extending the capability of large margin algorithms for unsupervised learning. One of the recent proposed algorithms is Maximum Margin Clustering (MMC). The MMC is an unsupervised SVMs algorithm that simultaneously estimates both the labels and the hyperplane parameters. Nevertheless, the optimization of the MMC algorithm is a non-convex problem. Most of the existing MMC methods rely on the reformulating and the relaxing of the non-convex optimization problem as semi-definite programs (SDP), which are computationally very expensive and only can handle small data sets. Moreover, most of these algorithms are two-class classification, which cannot be used for classification of remotely sensed data. In this paper, a new MMC algorithm is used that solve the original non-convex problem using Alternative Optimization method. This algorithm is also extended for multi-class classification and its performance is evaluated. The results of the proposed algorithm show that the algorithm has acceptable results for hyperspectral data clustering.

  5. Paving the road to maximum productivity.

    Science.gov (United States)

    Holland, C

    1998-01-01

    "Job security" is an oxymoron in today's environment of downsizing, mergers, and acquisitions. Workers find themselves living by new rules in the workplace that they may not understand. How do we cope? It is the leader's charge to take advantage of this chaos and create conditions under which his or her people can understand the need for change and come together with a shared purpose to effect that change. The clinical laboratory at Arkansas Children's Hospital has taken advantage of this chaos to down-size and to redesign how the work gets done to pave the road to maximum productivity. After initial hourly cutbacks, the workers accepted the cold, hard fact that they would never get their old world back. They set goals to proactively shape their new world through reorganizing, flexing staff with workload, creating a rapid response laboratory, exploiting information technology, and outsourcing. Today the laboratory is a lean, productive machine that accepts change as a way of life. We have learned to adapt, trust, and support each other as we have journeyed together over the rough roads. We are looking forward to paving a new fork in the road to the future.

  6. Maximum power flux of auroral kilometric radiation

    International Nuclear Information System (INIS)

    Benson, R.F.; Fainberg, J.

    1991-01-01

    The maximum auroral kilometric radiation (AKR) power flux observed by distant satellites has been increased by more than a factor of 10 from previously reported values. This increase has been achieved by a new data selection criterion and a new analysis of antenna spin modulated signals received by the radio astronomy instrument on ISEE 3. The method relies on selecting AKR events containing signals in the highest-frequency channel (1980, kHz), followed by a careful analysis that effectively increased the instrumental dynamic range by more than 20 dB by making use of the spacecraft antenna gain diagram during a spacecraft rotation. This analysis has allowed the separation of real signals from those created in the receiver by overloading. Many signals having the appearance of AKR harmonic signals were shown to be of spurious origin. During one event, however, real second harmonic AKR signals were detected even though the spacecraft was at a great distance (17 R E ) from Earth. During another event, when the spacecraft was at the orbital distance of the Moon and on the morning side of Earth, the power flux of fundamental AKR was greater than 3 x 10 -13 W m -2 Hz -1 at 360 kHz normalized to a radial distance r of 25 R E assuming the power falls off as r -2 . A comparison of these intense signal levels with the most intense source region values (obtained by ISIS 1 and Viking) suggests that multiple sources were observed by ISEE 3

  7. Maximum likelihood window for time delay estimation

    International Nuclear Information System (INIS)

    Lee, Young Sup; Yoon, Dong Jin; Kim, Chi Yup

    2004-01-01

    Time delay estimation for the detection of leak location in underground pipelines is critically important. Because the exact leak location depends upon the precision of the time delay between sensor signals due to leak noise and the speed of elastic waves, the research on the estimation of time delay has been one of the key issues in leak lovating with the time arrival difference method. In this study, an optimal Maximum Likelihood window is considered to obtain a better estimation of the time delay. This method has been proved in experiments, which can provide much clearer and more precise peaks in cross-correlation functions of leak signals. The leak location error has been less than 1 % of the distance between sensors, for example the error was not greater than 3 m for 300 m long underground pipelines. Apart from the experiment, an intensive theoretical analysis in terms of signal processing has been described. The improved leak locating with the suggested method is due to the windowing effect in frequency domain, which offers a weighting in significant frequencies.

  8. Ancestral Sequence Reconstruction with Maximum Parsimony.

    Science.gov (United States)

    Herbst, Lina; Fischer, Mareike

    2017-12-01

    One of the main aims in phylogenetics is the estimation of ancestral sequences based on present-day data like, for instance, DNA alignments. One way to estimate the data of the last common ancestor of a given set of species is to first reconstruct a phylogenetic tree with some tree inference method and then to use some method of ancestral state inference based on that tree. One of the best-known methods both for tree inference and for ancestral sequence inference is Maximum Parsimony (MP). In this manuscript, we focus on this method and on ancestral state inference for fully bifurcating trees. In particular, we investigate a conjecture published by Charleston and Steel in 1995 concerning the number of species which need to have a particular state, say a, at a particular site in order for MP to unambiguously return a as an estimate for the state of the last common ancestor. We prove the conjecture for all even numbers of character states, which is the most relevant case in biology. We also show that the conjecture does not hold in general for odd numbers of character states, but also present some positive results for this case.

  9. 49 CFR 230.24 - Maximum allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Maximum allowable stress. 230.24 Section 230.24... Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value. The maximum allowable stress value on any component of a steam locomotive boiler shall not exceed 1/4 of the ultimate...

  10. 20 CFR 226.52 - Total annuity subject to maximum.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Total annuity subject to maximum. 226.52... COMPUTING EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Railroad Retirement Family Maximum § 226.52 Total annuity subject to maximum. The total annuity amount which is compared to the maximum monthly amount to...

  11. Tailoring Water, Sanitation, and Hygiene (WASH) Targets for Soil-Transmitted Helminthiasis and Schistosomiasis Control.

    Science.gov (United States)

    Campbell, Suzy J; Biritwum, Nana-Kwadwo; Woods, Geordie; Velleman, Yael; Fleming, Fiona; Stothard, J Russell

    2018-01-01

    The World Health Organization's (WHO) 2015-2020 Global Strategy on water, sanitation, and hygiene (WASH) and neglected tropical diseases (NTDs) encourages integration, whilst maintaining existing structured NTD investments, and acceleration towards Sustainable Development Goal (SDG) targets. Accordingly, SDG-associated and WASH-NTD indicators have been developed, commencing important intersectoral dialogue, alongside opportunities for future disease-specific refinements. The rationale for soil-transmitted helminthiasis (STH)- and schistosomiasis-specific WASH considerations, and a traffic-light figure, are presented here to indicate where current international definitions may, or may not, suffice. Certain unique aspects in control dynamics and parasitic lifecycles, however, necessitate additional implementation research with more appropriate measurement indicators developed to record programmatic interventions and to define strategic priorities more effectively. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Soil transmitted helminths in animals – how is it possible for human transmission?

    Directory of Open Access Journals (Sweden)

    Choo Jia-Chi

    2016-11-01

    Full Text Available Objective: To determine the current prevalence of soil transmitted helminths (STH infections among cats and dogs in an animal shelter. Methods: A total of 442 animal's faecal samples were collected from the selected animal shelter located in Kuala Lumpur, Malaysia. The samples were screened by direct smear and further confirmed by formalin-ether sedimentation methods. Results: The overall prevalence of STH in animals was 48.4%. Among these, 51.5% and 45.8% were found in dogs and cats respectively. Among feline, hookworm was found to be the most predominant (41.7%, followed by Toxocara cati (4.6%. Whereas, hookworm was found to be the most predominant in canine (47%, followed by Toxocara canis (15.8% and Trichuris vulpis (5.9%. Conclusions: A high prevalence of STH infections was found among animals living in this local shelter. Hence, appropriate preventive measures should be taken to eradicate these infections.

  13. Historical perspective of sexually transmitted infections and their control in Peru.

    Science.gov (United States)

    García, P J

    2010-04-01

    In designing an effective national response to sexually transmitted infections (STIs), one must incorporate a historical perspective of previous efforts that have addressed different aspects of STIs. One must understand who have been the key players, what aspects of STIs were the focus of efforts (prevention, treatment or control), and which, if any, societal subgroups were targeted (i.e. sex workers, military, men who have sex with men [MSM], etc.). In addition, one must consider historical and modern attitudes towards sex, sexuality and STIs, especially in terms of taboos and stigmas that may be attached to each. Most importantly, one must recognize which efforts have succeeded, which have failed, and why. This paper presents a historical overview of the perceptions of and responses to STIs at different points in Peru's history, and discusses current efforts to build upon past successes and avoid repeating previous failures that could be helpful for other countries in the Latin American region.

  14. Contribution of the swine model in the study of human sexually transmitted infections

    DEFF Research Database (Denmark)

    Käser, Tobias; Renois, Fanny; Wilson, Heather L.

    2017-01-01

    The pig has garnered more and more interest as a model animal to study various conditions in humans. The growing success of the pig as an experimental animal model is explained by its similarities with humans in terms of anatomy, genetics, immunology, and physiology, by their manageable behavior...... transmitted diseases (STIs) like Chlamydia trachomatis. In the current review, we discuss the use of animal models for biomedical research on the major human STIs. We summarize results obtained in the most common animal models and focus on the contributions of the pig model towards the understanding...... of pathogenesis and the host immune response. In addition, we present the main features of the porcine model that are particularly relevant for the study of pathogens affecting human female and male genital tracts. We also inform on the technological advancements in the porcine toolbox to facilitate new...

  15. The Laboratory Diagnosis of Sexually Transmitted Infections in Cases of Sexual Assault and Abuse

    Directory of Open Access Journals (Sweden)

    Max A Chernesky

    2005-01-01

    Full Text Available Laboratory staff dealing with samples from victims must be aware that such patients have been psychologically traumatized and deserve special care. The help of a sexual assault care team should be sought if available, and appropriate specimens should be collected two to 10 days after an incident, preferably in a single visit. Specimens should be clearly labelled, and the laboratory should be informed. In the laboratory, all procedures need to be clearly documented. There are special requirements for the collection of forensic specimens and associated records, which may later be required for legal proceedings. The laboratory must know what the current legal status is for any test being used in that community. The present article serves as a guideline to more detailed practice standards for the investigation of individual sexually transmitted infections in assault and abuse situations.

  16. Recent sexually transmitted disease prevention efforts and their implications for AIDS health education.

    Science.gov (United States)

    Solomon, M Z; DeJong, W

    1986-01-01

    In the absence of a cure or vaccine for acquired immune deficiency syndrome (AIDS) educational and social marketing efforts to reduce the transmission of Human T-lymphotropic type III/lymphadenopathy-associated virus (HTLV-III/LAV) are currently our best hope for controlling the disease. Since 1983, the Centers for Disease Control (CDC) has funded a series of research studies to determine whether education efforts can successfully motivate the adoption of key behaviors relevant to the control of a variety of sexually transmitted diseases (STDs). Analysis of the first two studies which are now completed, and preliminary data from a third study, have documented dramatic changes in behavior, knowledge, and attitudes among clients in inner-city public health clinics. The authors describe the principles and underlying assumptions that have guided the design of their STD initiatives, drawing special attention to the implications for AIDS health education efforts.

  17. Half-width at half-maximum, full-width at half-maximum analysis

    Indian Academy of Sciences (India)

    addition to the well-defined parameter full-width at half-maximum (FWHM). The distribution of ... optical side-lobes in the diffraction pattern resulting in steep central maxima [6], reduc- tion of effects of ... and broad central peak. The idea of.

  18. Sexually transmitted infections: old foes on the rise.

    Science.gov (United States)

    Carmona-Gutierrez, Didac; Kainz, Katharina; Madeo, Frank

    2016-09-05

    Sexually transmitted infections (STIs) are commonly spread via sexual contact. It is estimated that one million STIs are acquired every day worldwide. Besides their impact on sexual, reproductive and neonatal health, they can cause disastrous and life-threatening complications if left untreated. In addition to this personal burden, STIs also represent a socioeconomic problem, deriving in treatment costs of tremendous proportions. Despite a substantial progress in diagnosis, treatment and prevention, the incidence of many common STIs is increasing, and STIs continue to represent a global public health problem and a major cause for morbidity and mortality. With this Special Issue, Microbial Cell provides an in-depth overview of the eight major STIs, covering all relevant features of each infection.

  19. Microanalysis by spectroscopy of transmitted electron energy losses

    International Nuclear Information System (INIS)

    Colliex, C.; Trebbia, P.

    1978-01-01

    Among the various signals which, in a transmission electron microscope, result from the interactions between the primary beam of well defined energy E 0 and the sample, the spectrum of the energy distribution of the electrons transmitted contains useful informations on the chemical and physical properties of the sample. Consequently the adaptation of an energy dispersive system on an electron microscope enables new fields of research to be investigated, particularly a localised chemical analysis technique with a space resolution scale equal to that of the electron microscope. It is this second aspect that we suggest describing in particular here. Already, this technique appears to be indispensable in the problems arising from the analysis of very small quantities of matter: detection limits in the order of 10 -19 to 10 -20 g (around 100 to 1000 atoms) would seem to be resonably possible [fr

  20. Trichomonas vaginalis - an indicator for other sexually transmitted infecting agents

    Directory of Open Access Journals (Sweden)

    Agrawal B

    1998-01-01

    Full Text Available The present study is based on 350 women having sexually transmitted diseases and 68 men counterparts. Trichomonas vaginalis was a significant contributor in 216 (61.7% out of 350 female SID cases′ and in 56 (82.3% out of 68 male counterparts. Further, out of 216 cases of T.vaginalis, 41 cases (32.5% were associated with infection with Candida species; 29 (23% with Neisseria gonorrhoea. 18 cases (14.3% with Haemophilus ducreyi and 11 cases (8.7%, Chlamydia trachomatis. Treponema pallidum was observed in 8 cases (6.3% which constituted a low percentage. Present study highlighted the importance of T. vaginalis by showing positivity in two-third cases which suggested that it can be an important indicator for other etiological STD agents in women.

  1. Sexually transmitted diseases during pregnancy: a synthesis of particularities.

    Science.gov (United States)

    Costa, Mariana Carvalho; Bornhausen Demarch, Eduardo; Azulay, David Rubem; Périssé, André Reynaldo Santos; Dias, Maria Fernanda Reis Gavazzoni; Nery, José Augusto da Costa

    2010-01-01

    Sexually transmitted diseases (STDs) have a significant prevalence in both the general population and pregnant women. Accordingly, we consider the physiological changes of the maternal organism that can alter the clinical course of these diseases. In addition, obstetric and neonatal complications may occur, resulting in increased maternal and infant morbidity and mortality. We explore features of the natural course and treatment during pregnancy of the major STDs: soft chancre, donovanosis, gonorrhea, chlamydia, viral hepatitis, genital herpes, human papillomavirus (HPV) infection, lymphogranuloma venereum, syphilis, and vulvovaginitis. We believe that health professionals should pay careful attention to STDs, particularly in relation to early diagnosis and precautions on the use of drugs during pregnancy. Prevention and partner treatment to achieve effective results are also extremely relevant.

  2. Height, zinc and soil-transmitted helminth infections in schoolchildren

    DEFF Research Database (Denmark)

    de Gier, Brechje; Mpabanzi, Liliane; Vereecken, Kim

    2015-01-01

    Soil-transmitted helminth (STH) infections and zinc deficiency are often found in low- and middle-income countries and are both known to affect child growth. However, studies combining data on zinc and STH are lacking. In two studies in schoolchildren in Cuba and Cambodia, we collected data...... on height, STH infection and zinc concentration in either plasma (Cambodia) or hair (Cuba). We analyzed whether STH and/or zinc were associated with height for age z-scores and whether STH and zinc were associated. In Cuba, STH prevalence was 8.4%; these were mainly Ascaris lumbricoides and Trichuris...... trichiura infections. In Cambodia, STH prevalence was 16.8%, mostly caused by hookworm. In Cuban children, STH infection had a strong association with height for age (aB-0.438, p = 0.001), while hair zinc was significantly associated with height for age only in STH uninfected children. In Cambodian children...

  3. Transmitting information of an object behind the obstacle to infinity

    Science.gov (United States)

    Xu, Bai Bing; Jiang, Wei Xiang; Meng, Ling Ling; Cui, Tie Jun

    2015-08-01

    We propose an illusion device that transforms a metallic cylinder into a Luneburg lens by using transformation optics. Such a transformed focusing lens guides electromagnetic waves to propagate around the central metallic cylinder smoothly and be focused on one spot, and thus the information of an object behind the obstacle can be transmitted to infinity. In order to realize the required-anisotropic parameters with high permittivity and low permeability, we design embedded split-ring resonators (SRRs) to increase the permittivity of the traditional SRR structures. In experiments, we fabricate and measure the transformed lens, and the tested results agree well with the numerical simulations and theoretical predictions. The proposed transformation lens can mimic some properties of Einstein gravitational lens because their wave propagation behaviors are very similar.

  4. Polarization Patterns of Transmitted Celestial Light under Wavy Water Surfaces

    Directory of Open Access Journals (Sweden)

    Guanhua Zhou

    2017-03-01

    Full Text Available This paper presents a model to describe the polarization patterns of celestial light, which includes sunlight and skylight, when refracted by wavy water surfaces. The polarization patterns and intensity distribution of refracted light through the wave water surface were calculated. The model was validated by underwater experimental measurements. The experimental and theoretical values agree well qualitatively. This work provides a quantitative description of the repolarization and transmittance of celestial light transmitted through wave water surfaces. The effects of wind speed and incident sources on the underwater refraction polarization patterns are discussed. Scattering skylight dominates the polarization patterns while direct solar light is the dominant source of the intensity of the underwater light field. Wind speed has an influence on disturbing the patterns under water.

  5. Hiv infection in patients of sexually transmitted disease

    Directory of Open Access Journals (Sweden)

    Sayal S

    1999-01-01

    Full Text Available A total of 1027 male patients suffering from sexually transmitted diseases (STD during 1990 to 1996 were screened for HIV infection. All cases were in the age group 17 years to 48 years. One hundred and sixty-seven STD cases (16.3% were found to have HIV infection. A rising trend in incidence of HIV infection in STD patients from 1990 (2.8% to 1996 (27.8% was noticed countrary to declining trend of STDs from 213 cases in 1990 to 79 cases in 1996. The incidence of HIV infection was 30.3% in lymphogranuloma venereum, 19.5% in chancroid, 13.5% in syphilis, 17.6% in herpes genitatis, 6.7% in gonorrhoea and 11.2% in other STD cases.

  6. Dynein Transmits Polarized Actomyosin Cortical Flows to Promote Centrosome Separation

    Directory of Open Access Journals (Sweden)

    Alessandro De Simone

    2016-03-01

    Full Text Available The two centrosomes present at the onset of mitosis must separate in a timely and accurate fashion to ensure proper bipolar spindle assembly. The minus-end-directed motor dynein plays a pivotal role in centrosome separation, but the underlying mechanisms remain elusive, particularly regarding how dynein coordinates this process in space and time. We addressed these questions in the one-cell C. elegans embryo, using a combination of 3D time-lapse microscopy and computational modeling. Our analysis reveals that centrosome separation is powered by the joint action of dynein at the nuclear envelope and at the cell cortex. Strikingly, we demonstrate that dynein at the cell cortex acts as a force-transmitting device that harnesses polarized actomyosin cortical flows initiated by the centrosomes earlier in the cell cycle. This mechanism elegantly couples cell polarization with centrosome separation, thus ensuring faithful cell division.

  7. Searching for unknown transfusion-transmitted hepatitis viruses

    DEFF Research Database (Denmark)

    Edgren, G.; Hjalgrim, H.; Rostgaard, K.

    2018-01-01

    Background: Both hepatitis B and C viruses were transmitted through blood transfusion before implementation of donor screening. The existence of additional, yet unknown transfusion transmittable agents causing liver disease could have important public health implications. Methods: Analyses were...... 1992 to account for the effect of screening for hepatitis C virus. Results: A total of 1 482 922 transfused patients were included in the analyses. Analyses showed evidence of transfusion transmission of liver diseases before, but not after the implementation of hepatitis C virus screening in 1992...... for transfusion transmission of agents causing liver disease after the implementation of screening for hepatitis B and C, and suggest that if such transmission does occur, it is rare....

  8. Arsenolite: a quasi-hydrostatic solid pressure-transmitting medium

    International Nuclear Information System (INIS)

    Sans, J A; Manjón, F J; Popescu, C; Muñoz, A; Rodríguez-Hernández, P; Jordá, J L; Rey, F

    2016-01-01

    This study reports the experimental characterization of the hydrostatic properties of arsenolite (As 4 O 6 ), a molecular solid which is one of the softest minerals in the absence of hydrogen bonding. The high compressibility of arsenolite and its stability up to 15 GPa have been proved by x-ray diffraction measurements, and the progressive loss of hydrostaticity with increasing pressure up to 20 GPa has been monitored by ruby photoluminescence. Arsenolite has been found to exhibit hydrostatic behavior up to 2.5 GPa and a quasi-hydrostatic behavior up to 10 GPa at room temperature. This result opens the way to explore other molecular solids as possible quasi-hydrostatic pressure-transmitting media. The validity of arsenolite as an insulating, stable, non-penetrating and quasi-hydrostatic medium is explored by the study of the x-ray diffraction of zeolite ITQ-29 at high pressure. (paper)

  9. The pressure distribution for biharmonic transmitting array: theoretical study

    Science.gov (United States)

    Baranowska, A.

    2005-03-01

    The aim of the paper is theoretical analysis of the finite amplitude waves interaction problem for the biharmonic transmitting array. We assume that the array consists of 16 circular pistons of the same dimensions that regrouped in two sections. Two different arrangements of radiating elements were considered. In this situation the radiating surface is non-continuous without axial symmetry. The mathematical model was built on the basis of the Khokhlov - Zabolotskaya - Kuznetsov (KZK) equation. To solve the problem the finite-difference method was applied. On-axis pressure amplitude for different frequency waves as a function of distance from the source, transverse pressure distribution of these waves at fixed distances from the source and pressure amplitude distribution for them at fixed planes were examined. Especially changes of normalized pressure amplitude for difference frequency were studied. The paper presents mathematical model and some results of theoretical investigations obtained for different values of source parameters.

  10. Vaccination strategies for SIR vector-transmitted diseases.

    Science.gov (United States)

    Cruz-Pacheco, Gustavo; Esteva, Lourdes; Vargas, Cristobal

    2014-08-01

    Vector-borne diseases are one of the major public health problems in the world with the fastest spreading rate. Control measures have been focused on vector control, with poor results in most cases. Vaccines should help to reduce the diseases incidence, but vaccination strategies should also be defined. In this work, we propose a vector-transmitted SIR disease model with age-structured population subject to a vaccination program. We find an expression for the age-dependent basic reproductive number R(0), and we show that the disease-free equilibrium is locally stable for R(0) ≤ 1, and a unique endemic equilibrium exists for R(0) > 1. We apply the theoretical results to public data to evaluate vaccination strategies, immunization levels, and optimal age of vaccination for dengue disease.

  11. Drug resistance in the sexually transmitted protozoan Trichomonas vaginalis

    Institute of Scientific and Technical Information of China (English)

    REBECCA L DUNNE; LINDA A DUNN; PETER UPCROFT; PETER J O'DONOGHUE; JACQUELINE A UPCROFT

    2003-01-01

    Trichomoniasis is the most common, sexually transmitted infection. It is caused by the flagellated protozoan parasite Trichomonas vaginalis. Symptoms include vaginitis and infections have been associated with preterm delivery, low birth weight and increased infant mortality, as well as predisposing to HIV/AIDS and cervical cancer. Trichomoniasis has the highest prevalence and incidence of any sexually transmitted infection. The 5-nitroimidazole drugs, of which metronidazole is the most prescribed, are the only approved,effective drugs to treat trichomoniasis. Resistance against metronidazole is frequently reported and crossresistance among the family of 5-nitroimidazole drugs is common, leaving no alternative for treatment, with some cases remaining unresolved. The mechanism of metronidazole resistance in T. vaginalis from treatment failures is not well understood, unlike resistance which is developed in the laboratory under increasing metronidazole pressure. In the latter situation, hydrogenosomal function which is involved in activation of the prodrug, metronidazole, is down-regulated. Reversion to sensitivity is incomplete after removal of drug pressure in the highly resistant parasites while clinically resistant strains, so far analysed, maintain their resistance levels in the absence of drug pressure. Although anaerobic resistance has been regarded as a laboratory induced phenomenon, it clearly has been demonstrated in clinical isolates. Pursuit of both approaches will allow dissection of the underlying mechanisms. Many alternative drugs and treatments have been tested in vivo in cases of refractory trichomoniasis, as well as in vitro with some successes including the broad spectrum anti-parasitic drug nitazoxanide. Drug resistance incidence in T. vaginalis appears to be on the increase and improved surveillance of treatment failures is urged.

  12. Cosmic shear measurement with maximum likelihood and maximum a posteriori inference

    Science.gov (United States)

    Hall, Alex; Taylor, Andy

    2017-06-01

    We investigate the problem of noise bias in maximum likelihood and maximum a posteriori estimators for cosmic shear. We derive the leading and next-to-leading order biases and compute them in the context of galaxy ellipticity measurements, extending previous work on maximum likelihood inference for weak lensing. We show that a large part of the bias on these point estimators can be removed using information already contained in the likelihood when a galaxy model is specified, without the need for external calibration. We test these bias-corrected estimators on simulated galaxy images similar to those expected from planned space-based weak lensing surveys, with promising results. We find that the introduction of an intrinsic shape prior can help with mitigation of noise bias, such that the maximum a posteriori estimate can be made less biased than the maximum likelihood estimate. Second-order terms offer a check on the convergence of the estimators, but are largely subdominant. We show how biases propagate to shear estimates, demonstrating in our simple set-up that shear biases can be reduced by orders of magnitude and potentially to within the requirements of planned space-based surveys at mild signal-to-noise ratio. We find that second-order terms can exhibit significant cancellations at low signal-to-noise ratio when Gaussian noise is assumed, which has implications for inferring the performance of shear-measurement algorithms from simplified simulations. We discuss the viability of our point estimators as tools for lensing inference, arguing that they allow for the robust measurement of ellipticity and shear.

  13. Normative evaluation of blood banks in the Brazilian Amazon region in respect to the prevention of transfusion-transmitted malaria

    Directory of Open Access Journals (Sweden)

    Daniel Roberto Coradi Freitas

    2014-12-01

    Full Text Available Objective:To evaluate blood banks in the Brazilian Amazon region with regard to structure and procedures directed toward the prevention of transfusion-transmitted malaria (TTM.Methods:This was a normative evaluation based on the Brazilian National Health Surveillance Agency (ANVISA Resolution RDC No. 153/2004. Ten blood banks were included in the study and classified as 'adequate' (≥80 points, 'partially adequate' (from 50 to 80 points, or 'inadequate' (<50 points. The following components were evaluated: 'donor education' (5 points, 'clinical screening' (40 points, 'laboratory screening' (40 points and 'hemovigilance' (15 points.Results:The overall median score was 49.8 (minimum = 16; maximum = 78. Five blood banks were classified as 'inadequate' and five as 'partially adequate'. The median clinical screening score was 26 (minimum = 16; maximum = 32. The median laboratory screening score was 20 (minimum = 0; maximum = 32. Eight blood banks performed laboratory tests for malaria; six tested all donations. Seven used thick smears, but only one performed this procedure in accordance with Ministry of Health requirements. One service had a Program of External Quality Evaluation for malaria testing. With regard to hemovigilance, two institutions reported having procedures to detect cases of transfusion-transmitted malaria.Conclusion:Malaria is neglected as a blood–borne disease in the blood banks of the Brazilian Amazon region. None of the institutions were classified as 'adequate' in the overall classification or with regard to clinical screening and laboratory screening. Blood bank professionals, the Ministry of Health and Health Surveillance service managers need to pay more attention to this matter so that the safety procedures required by law are complied with.

  14. Maximum parsimony, substitution model, and probability phylogenetic trees.

    Science.gov (United States)

    Weng, J F; Thomas, D A; Mareels, I

    2011-01-01

    The problem of inferring phylogenies (phylogenetic trees) is one of the main problems in computational biology. There are three main methods for inferring phylogenies-Maximum Parsimony (MP), Distance Matrix (DM) and Maximum Likelihood (ML), of which the MP method is the most well-studied and popular method. In the MP method the optimization criterion is the number of substitutions of the nucleotides computed by the differences in the investigated nucleotide sequences. However, the MP method is often criticized as it only counts the substitutions observable at the current time and all the unobservable substitutions that really occur in the evolutionary history are omitted. In order to take into account the unobservable substitutions, some substitution models have been established and they are now widely used in the DM and ML methods but these substitution models cannot be used within the classical MP method. Recently the authors proposed a probability representation model for phylogenetic trees and the reconstructed trees in this model are called probability phylogenetic trees. One of the advantages of the probability representation model is that it can include a substitution model to infer phylogenetic trees based on the MP principle. In this paper we explain how to use a substitution model in the reconstruction of probability phylogenetic trees and show the advantage of this approach with examples.

  15. Maximum power point tracking of partially shaded solar photovoltaic arrays

    Energy Technology Data Exchange (ETDEWEB)

    Roy Chowdhury, Shubhajit; Saha, Hiranmay [IC Design and Fabrication Centre, Department of Electronics and Telecommunication Engineering, Jadavpur University (India)

    2010-09-15

    The paper presents the simulation and hardware implementation of maximum power point (MPP) tracking of a partially shaded solar photovoltaic (PV) array using a variant of Particle Swarm Optimization known as Adaptive Perceptive Particle Swarm Optimization (APPSO). Under partially shaded conditions, the photovoltaic (PV) array characteristics get more complex with multiple maxima in the power-voltage characteristic. The paper presents an algorithmic technique to accurately track the maximum power point (MPP) of a PV array using an APPSO. The APPSO algorithm has also been validated in the current work. The proposed technique uses only one pair of sensors to control multiple PV arrays. This result in lower cost and higher accuracy of 97.7% compared to earlier obtained accuracy of 96.41% using Particle Swarm Optimization. The proposed tracking technique has been mapped onto a MSP430FG4618 microcontroller for tracking and control purposes. The whole system based on the proposed has been realized on a standard two stage power electronic system configuration. (author)

  16. Constraints on pulsar masses from the maximum observed glitch

    Science.gov (United States)

    Pizzochero, P. M.; Antonelli, M.; Haskell, B.; Seveso, S.

    2017-07-01

    Neutron stars are unique cosmic laboratories in which fundamental physics can be probed in extreme conditions not accessible to terrestrial experiments. In particular, the precise timing of rotating magnetized neutron stars (pulsars) reveals sudden jumps in rotational frequency in these otherwise steadily spinning-down objects. These 'glitches' are thought to be due to the presence of a superfluid component in the star, and offer a unique glimpse into the interior physics of neutron stars. In this paper we propose an innovative method to constrain the mass of glitching pulsars, using observations of the maximum glitch observed in a star, together with state-of-the-art microphysical models of the pinning interaction between superfluid vortices and ions in the crust. We study the properties of a physically consistent angular momentum reservoir of pinned vorticity, and we find a general inverse relation between the size of the maximum glitch and the pulsar mass. We are then able to estimate the mass of all the observed glitchers that have displayed at least two large events. Our procedure will allow current and future observations of glitching pulsars to constrain not only the physics of glitch models but also the superfluid properties of dense hadronic matter in neutron star interiors.

  17. Weak currents

    International Nuclear Information System (INIS)

    Leite Lopes, J.

    1976-01-01

    A survey of the fundamental ideas on weak currents such as CVC and PCAC and a presentation of the Cabibbo current and the neutral weak currents according to the Salam-Weinberg model and the Glashow-Iliopoulos-Miami model are given [fr

  18. Spin current

    CERN Document Server

    Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

    2012-01-01

    In a new branch of physics and technology called spin-electronics or spintronics, the flow of electrical charge (usual current) as well as the flow of electron spin, the so-called 'spin current', are manipulated and controlled together. This book provides an introduction and guide to the new physics and application of spin current.

  19. The maximum sizes of large scale structures in alternative theories of gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Sourav [IUCAA, Pune University Campus, Post Bag 4, Ganeshkhind, Pune, 411 007 India (India); Dialektopoulos, Konstantinos F. [Dipartimento di Fisica, Università di Napoli ' Federico II' , Complesso Universitario di Monte S. Angelo, Edificio G, Via Cinthia, Napoli, I-80126 Italy (Italy); Romano, Antonio Enea [Instituto de Física, Universidad de Antioquia, Calle 70 No. 52–21, Medellín (Colombia); Skordis, Constantinos [Department of Physics, University of Cyprus, 1 Panepistimiou Street, Nicosia, 2109 Cyprus (Cyprus); Tomaras, Theodore N., E-mail: sbhatta@iitrpr.ac.in, E-mail: kdialekt@gmail.com, E-mail: aer@phys.ntu.edu.tw, E-mail: skordis@ucy.ac.cy, E-mail: tomaras@physics.uoc.gr [Institute of Theoretical and Computational Physics and Department of Physics, University of Crete, 70013 Heraklion (Greece)

    2017-07-01

    The maximum size of a cosmic structure is given by the maximum turnaround radius—the scale where the attraction due to its mass is balanced by the repulsion due to dark energy. We derive generic formulae for the estimation of the maximum turnaround radius in any theory of gravity obeying the Einstein equivalence principle, in two situations: on a spherically symmetric spacetime and on a perturbed Friedman-Robertson-Walker spacetime. We show that the two formulae agree. As an application of our formula, we calculate the maximum turnaround radius in the case of the Brans-Dicke theory of gravity. We find that for this theory, such maximum sizes always lie above the ΛCDM value, by a factor 1 + 1/3ω, where ω>> 1 is the Brans-Dicke parameter, implying consistency of the theory with current data.

  20. Window period donations during primary cytomegalovirus infection and risk of transfusion-transmitted infections.

    Science.gov (United States)

    Ziemann, Malte; Heuft, Hans-Gert; Frank, Kerstin; Kraas, Sabine; Görg, Siegfried; Hennig, Holger

    2013-05-01

    Donors with short interdonation intervals (e.g., apheresis donors) have an increased risk of window period donations. The frequency of cytomegalovirus (CMV) window period donations is important information to decide whether selection of seronegative donors might be advantageous for patients at risk for transfusion-transmitted CMV infections (TT-CMV). CMV seroconversion in 93 donors with positive results in routine CMV antibody testing within at most 35 days after the last seronegative sample was evaluated by Western blot and/or a second antibody test. In donors with unconfirmed seroconversion, an additional later sample was tested. Concentration of CMV DNA was determined in pre- and postseroconversion samples. CMV seroconversion was confirmed in 12 donors (13%). Among these, the last seronegative sample was CMV DNA positive in three donors (25%, below 30 IU/mL). The first seropositive sample was CMV DNA positive in 10 donors (83%, maximum 1600 IU/mL). Both prevalence and median concentration of CMV DNA were higher in the first seropositive sample (p = 0.004 and p = 0.02), with maximum concentrations being reached about 2 weeks after seroconversion. No CMV DNA was detected in samples from donors with unconfirmed seroconversion. At least in donors with short interdonation intervals, most suspected CMV seroconversions are due to false-positive results of the screening test. As window period donations are rare and contain less CMV DNA than the first seropositive donation, avoidance of blood products from primarily seropositive donors is especially helpful to avoid TT-CMV if donors with short interdonation intervals are concerned. © 2013 American Association of Blood Banks.

  1. Marginal Maximum Likelihood Estimation of Item Response Models in R

    Directory of Open Access Journals (Sweden)

    Matthew S. Johnson

    2007-02-01

    Full Text Available Item response theory (IRT models are a class of statistical models used by researchers to describe the response behaviors of individuals to a set of categorically scored items. The most common IRT models can be classified as generalized linear fixed- and/or mixed-effect models. Although IRT models appear most often in the psychological testing literature, researchers in other fields have successfully utilized IRT-like models in a wide variety of applications. This paper discusses the three major methods of estimation in IRT and develops R functions utilizing the built-in capabilities of the R environment to find the marginal maximum likelihood estimates of the generalized partial credit model. The currently available R packages ltm is also discussed.

  2. Densification of porous bodies in a granular pressure-transmitting medium

    International Nuclear Information System (INIS)

    Olevsky, E.A.; Ma, J.; LaSalvia, J.C.; Meyers, M.A.

    2007-01-01

    Densification is a critical step in the manufacture of near-net-shaped components via powder processing. A non-isostatic stress state will in general result in shape distortion in addition to densification. In the quasi-isostatic pressing (QIP) process the green body is placed into a granular pressure-transmitting medium (i.e. PTM), which is itself contained in a rigid die. Upon the application of a uniaxial load, the PTM redistributes the tractions on the green body, thereby creating a stress state that is quasi-isostatic. The character of the deformation of the PTM is studied using model experiments on pressing of the PTM in a rigid die and a scanning electron microscopy analysis of the PTM powder. An important problem of the optimization of the PTM chemical composition enabling the maximum densification of a porous specimen with the minimum possible shape distortion is solved. The results of modeling agree satisfactorily with the experimental data on cold QIPing Ti and Ni powder samples and hot QIPing TiC-TiNi cermet composites

  3. Prevalence of Sexually Transmitted Diseases and Blood-Borne Transmitted Infections among Male Patients with Antisocial Personality Disorder

    Directory of Open Access Journals (Sweden)

    Hamza Yıldız

    2015-03-01

    Full Text Available Objective: The aim of this study was to compare the patients who have antisocial personality disorder (ASPD and the healthy individuals in terms of sexually transmitted diseases (STDs and Blood-Borne Transmitted Infections (BTIs prevalences. Methods: This study is a prospective, single-center, open-label, non-randomized controlled clinical study. There were two groups in the study. The patient group consistsed of 100 males who were diagnosed as ASPD with a clinical interview form. The control group consisted of 98 healthy males who did not have any psychiatric disorder. Dermatologic examination was performed, and clinical findings were recorded. Results: The mean age of the patient group was 21.96±2.40 (range 20-37 years. The mean age of the control group was 24.20±2.88 (21-36 years. The most common disease was gonorrhea (25% followed by genital wart (11%, molluskum contagiosum (5%, HBsAg (4%, and HSV-2 seropositivity (4% in the patients group. In the control group, HSV-2 seropositivity (4.08%, genital wart (3.06%, molluskum contagiosum (3.06%, and gonorrhe (1.02% were commonly seen in the control group. STDs and/or BVTIs were found more common in the patients group (82% than that in the control group (45.91% (X2=30.62, p=0.000. Conclusions: The patients with ASPD are at greater risk than normal population to catch a STDs or BTIs because of their lower educational levels and riskier behaviors. This condition entertains a risk in the general population and the patients themselves.

  4. Maximum entropy production rate in quantum thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Beretta, Gian Paolo, E-mail: beretta@ing.unibs.i [Universita di Brescia, via Branze 38, 25123 Brescia (Italy)

    2010-06-01

    In the framework of the recent quest for well-behaved nonlinear extensions of the traditional Schroedinger-von Neumann unitary dynamics that could provide fundamental explanations of recent experimental evidence of loss of quantum coherence at the microscopic level, a recent paper [Gheorghiu-Svirschevski 2001 Phys. Rev. A 63 054102] reproposes the nonlinear equation of motion proposed by the present author [see Beretta G P 1987 Found. Phys. 17 365 and references therein] for quantum (thermo)dynamics of a single isolated indivisible constituent system, such as a single particle, qubit, qudit, spin or atomic system, or a Bose-Einstein or Fermi-Dirac field. As already proved, such nonlinear dynamics entails a fundamental unifying microscopic proof and extension of Onsager's reciprocity and Callen's fluctuation-dissipation relations to all nonequilibrium states, close and far from thermodynamic equilibrium. In this paper we propose a brief but self-contained review of the main results already proved, including the explicit geometrical construction of the equation of motion from the steepest-entropy-ascent ansatz and its exact mathematical and conceptual equivalence with the maximal-entropy-generation variational-principle formulation presented in Gheorghiu-Svirschevski S 2001 Phys. Rev. A 63 022105. Moreover, we show how it can be extended to the case of a composite system to obtain the general form of the equation of motion, consistent with the demanding requirements of strong separability and of compatibility with general thermodynamics principles. The irreversible term in the equation of motion describes the spontaneous attraction of the state operator in the direction of steepest entropy ascent, thus implementing the maximum entropy production principle in quantum theory. The time rate at which the path of steepest entropy ascent is followed has so far been left unspecified. As a step towards the identification of such rate, here we propose a possible

  5. Determination of the maximum-depth to potential field sources by a maximum structural index method

    Science.gov (United States)

    Fedi, M.; Florio, G.

    2013-01-01

    A simple and fast determination of the limiting depth to the sources may represent a significant help to the data interpretation. To this end we explore the possibility of determining those source parameters shared by all the classes of models fitting the data. One approach is to determine the maximum depth-to-source compatible with the measured data, by using for example the well-known Bott-Smith rules. These rules involve only the knowledge of the field and its horizontal gradient maxima, and are independent from the density contrast. Thanks to the direct relationship between structural index and depth to sources we work out a simple and fast strategy to obtain the maximum depth by using the semi-automated methods, such as Euler deconvolution or depth-from-extreme-points method (DEXP). The proposed method consists in estimating the maximum depth as the one obtained for the highest allowable value of the structural index (Nmax). Nmax may be easily determined, since it depends only on the dimensionality of the problem (2D/3D) and on the nature of the analyzed field (e.g., gravity field or magnetic field). We tested our approach on synthetic models against the results obtained by the classical Bott-Smith formulas and the results are in fact very similar, confirming the validity of this method. However, while Bott-Smith formulas are restricted to the gravity field only, our method is applicable also to the magnetic field and to any derivative of the gravity and magnetic field. Our method yields a useful criterion to assess the source model based on the (∂f/∂x)max/fmax ratio. The usefulness of the method in real cases is demonstrated for a salt wall in the Mississippi basin, where the estimation of the maximum depth agrees with the seismic information.

  6. Maximum permissible concentrations of uranium in air

    CERN Document Server

    Adams, N

    1973-01-01

    The retention of uranium by bone and kidney has been re-evaluated taking account of recently published data for a man who had been occupationally exposed to natural uranium aerosols and for adults who had ingested uranium at the normal dietary levels. For life-time occupational exposure to uranium aerosols the new retention functions yield a greater retention in bone and a smaller retention in kidney than the earlier ones, which were based on acute intakes of uranium by terminal patients. Hence bone replaces kidney as the critical organ. The (MPC) sub a for uranium 238 on radiological considerations using the current (1959) ICRP lung model for the new retention functions is slightly smaller than for earlier functions but the (MPC) sub a determined by chemical toxicity remains the most restrictive.

  7. Weighted Maximum-Clique Transversal Sets of Graphs

    OpenAIRE

    Chuan-Min Lee

    2011-01-01

    A maximum-clique transversal set of a graph G is a subset of vertices intersecting all maximum cliques of G. The maximum-clique transversal set problem is to find a maximum-clique transversal set of G of minimum cardinality. Motivated by the placement of transmitters for cellular telephones, Chang, Kloks, and Lee introduced the concept of maximum-clique transversal sets on graphs in 2001. In this paper, we study the weighted version of the maximum-clique transversal set problem for split grap...

  8. Measurement of Forces and Moments Transmitted to the Residual Limb

    Science.gov (United States)

    2009-08-01

    alignment of a prosthesis. Walking speed and cadence will be measured during the baseline conditions and a metronome will be used to help subjects...reproduced and you will be allowed to walk with your original alignment briefly to refresh your memory on how it feels. A metronome may be used to...speed and compare the maximum pressures to those in activity A (A metronome will be used to help you establish a cadence that is 10% - 15% faster than

  9. Analysis of the maximum likelihood channel estimator for OFDM systems in the presence of unknown interference

    Science.gov (United States)

    Dermoune, Azzouz; Simon, Eric Pierre

    2017-12-01

    This paper is a theoretical analysis of the maximum likelihood (ML) channel estimator for orthogonal frequency-division multiplexing (OFDM) systems in the presence of unknown interference. The following theoretical results are presented. Firstly, the uniqueness of the ML solution for practical applications, i.e., when thermal noise is present, is analytically demonstrated when the number of transmitted OFDM symbols is strictly greater than one. The ML solution is then derived from the iterative conditional ML (CML) algorithm. Secondly, it is shown that the channel estimate can be described as an algebraic function whose inputs are the initial value and the means and variances of the received samples. Thirdly, it is theoretically demonstrated that the channel estimator is not biased. The second and the third results are obtained by employing oblique projection theory. Furthermore, these results are confirmed by numerical results.

  10. Implications of host genetic variation on the risk and prevalence of infectious diseases transmitted through the environment.

    Science.gov (United States)

    Doeschl-Wilson, Andrea B; Davidson, R; Conington, J; Roughsedge, T; Hutchings, M R; Villanueva, B

    2011-07-01

    Previous studies have shown that host genetic heterogeneity in the response to infectious challenge can affect the emergence risk and the severity of diseases transmitted through direct contact between individuals. However, there is substantial uncertainty about the degree and direction of influence owing to different definitions of genetic variation, most of which are not in line with the current understanding of the genetic architecture of disease traits. Also, the relevance of previous results for diseases transmitted through environmental sources is unclear. In this article a compartmental genetic-epidemiological model was developed to quantify the impact of host genetic diversity on epidemiological characteristics of diseases transmitted through a contaminated environment. The model was parameterized for footrot in sheep. Genetic variation was defined through continuous distributions with varying shape and degree of dispersion for different disease traits. The model predicts a strong impact of genetic heterogeneity on the disease risk and its progression and severity, as well as on observable host phenotypes, when dispersion in key epidemiological parameters is high. The impact of host variation depends on the disease trait for which variation occurs and on environmental conditions affecting pathogen survival. In particular, compared to homogeneous populations with the same average susceptibility, disease risk and severity are substantially higher in populations containing a large proportion of highly susceptible individuals, and the differences are strongest when environmental contamination is low. The implications of our results for the recording and analysis of disease data and for predicting response to selection are discussed.

  11. Home Healthcare Program for Soil-Transmitted Helminthiasis in Schoolchildren along the Mekong River Basin.

    Science.gov (United States)

    Kaewpitoon, Soraya J; Loyd, Ryan A; Kaewpitoon, Natthawut

    2015-05-01

    Soil-transmitted helminths (STH) are among the most important groups of infectious agents responsible for physical and intellectual growth retardation in children worldwide. Current status is need requiredfor the development of control programs. To determine the STH infections among the schoolchildren in the Mekong River basin near rural Ubon Ratchathani, Thailand and Champassak, Laos PDR, including their caregiver knowledge and attitude concerning prevention of STH infections. A cross sectional survey was designed as a home healthcare programfrom October 2009 to April 2012. 1,957 fecal samples were collected from children aged 5-12 years in five districts of Ubon Ratchathani province (1,012 fecal samples; Khong Chiam, Si Mueang Mai, Phibun Mangsahan, Sirindhorn, and Pho Sai), Thailand, and one district of Champassak Province (945 fecal samples; Pakse), Lao PDR. Fecal samples were prepared by the modified formalin ethylacetate concentration technique, and determined by light microscope. The knowledge and attitude of children's caregivers concerning prevention of soil-transmitted helminth infections were completed interviewed by semi-structured questionnaires. The overall intestinal helminth prevalence rate was 11.88%. Classified by species the STHs were as follows: Ascaris lumbricoides (30.9%), Trichuris trichiura (21.7%), and hookworm (20.5%). The highest prevalence was recorded in children aged 9 years and above. The highest prevalence of STH infection was found in the Pakse district of Laos PDR (16.08%). The intensities of infection with A. lumbricoides, T trichiura, and Hookworm were 1.82 ± 0.36, 1.32 ± 0.30, and 1.29 ± 0.32, respectively. 1,077 of caregivers were completed interviewed and found that the caregivers had fair levels of knowledge and attitude regarding soil-transmitted helminthiasis. These results suggest that priority should be given to STH eradication, the development of control programs in the Mekong River Basin, and the provision of

  12. Three-level grid-connected photovoltaic inverter with maximum power point tracking

    International Nuclear Information System (INIS)

    Tsang, K.M.; Chan, W.L.

    2013-01-01

    Highlight: ► This paper reports a novel 3-level grid connected photovoltaic inverter. ► The inverter features maximum power point tracking and grid current shaping. ► The inverter can be acted as an active filter and a renewable power source. - Abstract: This paper presents a systematic way of designing control scheme for a grid-connected photovoltaic (PV) inverter featuring maximum power point tracking (MPPT) and grid current shaping. Unlike conventional design, only four power switches are required to achieve three output levels and it is not necessary to use any phase-locked-loop circuitry. For the proposed scheme, a simple integral controller has been designed for the tracking of the maximum power point of a PV array based on an improved extremum seeking control method. For the grid-connected inverter, a current loop controller and a voltage loop controller have been designed. The current loop controller is designed to shape the inverter output current while the voltage loop controller can maintain the capacitor voltage at a certain level and provide a reference inverter output current for the PV inverter without affecting the maximum power point of the PV array. Experimental results are included to demonstrate the effectiveness of the tracking and control scheme.

  13. [Parasitic zoonoses transmitted by drinking water. Giardiasis and cryptosporidiosis].

    Science.gov (United States)

    Exner, M; Gornik, V

    2004-07-01

    Nowadays, the parasitic zoonose organisms Giardia lamblia und Cryptosporidium spp. are among the most relevant pathogens of drinking water-associated disease outbreaks. These pathogens are transmitted via a fecal-oral route; in both cases the dose of infection is low. Apart from person-to-person or animal-to-person transmissions, the consumption of contaminated food and water are further modes of transmission. The disease is mainly characterized by gastrointestinal symptoms. In industrialized countries, the prevalence rate of giardiasis is 2-5 % and of cryptosporidiosis 1-3%. Throughout the world, a large number of giardiasis and cryptosporidiosis outbreaks associated with drinking water were published; in 2001 the first case in Germany was identified. Giardia and Cryptosporidium are detected in surface water and sporadically in unprotected groundwater. Use of these waters for drinking water abstraction makes high demands on the technology of the treatment process: because of the disinfectant resistance of the parasites, safe elimination methods are needed, which even at high contamination levels of source water guarantee safe drinking water. Further measures for prevention and control are implementation of the HACCP concept, which includes the whole chain of procedures of drinking water supply from catchment via treatment to tap and a quality management system.

  14. Failure to transmit avian vacuolar myelinopathy to mallard ducks

    Science.gov (United States)

    Larsen, R.S.; Nutter, F.B.; Augspurger, T.; Rocke, T.E.; Thomas, N.J.; Stoskopf, M.K.

    2003-01-01

    Avian vacuolar myelinopathy (AVM) is a neurologic disease that has been diagnosed in free-ranging birds in the southeastern United States. Bald eagles (Haliaeetus leuocephalus), American coots (Fulica americana), and mallards (Anas platyrhynchos) have been affected. Previous investigations have not determined the etiology of this disease. In November and December 2002, we attempted to induce AVM in game-farmed mallards through four, 7-day exposure trials. Mallards were housed in six groups of eight, with two of these groups serving as controls. One group was housed with AVM-affected coots; one group was tube fed daily with water from the lake where affected coots were captured; one group was tube fed daily with aquatic vegetation (Hydrilla verticillata) from the same lake; and another group was tube fed daily with sediment from the lake. No ducks exhibited clinical neurologic abnormalities consistent with AVM and no evidence of AVM was present at histopathologic examination of brain tissue. Although limitations in sample size, quantity of individual doses, frequency of dose administration, duration of exposure, and timing of these trials restrict the interpretation of the findings, AVM was not readily transmitted by direct contact, water, hydrilla, or sediment in this investigation.

  15. Sexually Transmitted Diseases and Travel: From Boudoir to Bordello.

    Science.gov (United States)

    Avery, Ann K; Zenilman, Jonathan M

    2015-10-01

    Travel has historically been an important risk factor for acquisition of sexually transmitted infections (STIs). Travel is often associated with a sense of adventure, periods of loneliness, and exploration away from one's home environment-which often form a milieu in which sexual activity can occur with new partners. Survey data clearly demonstrate that out-of-country travel is associated with recruitment of new sex partners and increased STI risk. Pretravel counseling to prevent STI risk is variable, and there is little evidence that it modifies risk behavior. Some travel occurs specifically for sexual purposes, such as the sexual tourism junkets to Southeast Asian destinations which became popular during the 1980s or the more recent rise in the popularity of circuit parties for men who have sex with men. Some travel situations pose particularly high risks. For example, military deployments and assignments to work camps such as those for oil extraction occur in the context of large groups of individuals of reproductive age, often predominantly males, exposed to high levels of stress in unfamiliar environments. Additionally, over the past decade, the Internet has dramatically changed the ability to identify sexual partners while traveling.

  16. Physical and Sexual Violence and Incident Sexually Transmitted Infections

    Science.gov (United States)

    Anand, Mallika; Redding, Colleen A.; Peipert, Jeffrey F.

    2009-01-01

    Abstract Objective To investigate whether women aged 13–35 who were victims of interpersonal violence were more likely than nonvictims to experience incident sexually transmitted infections (STIs). Methods We examined 542 women aged 13–35 enrolled in Project PROTECT, a randomized clinical trial that compared two different methods of computer-based intervention to promote the use of dual methods of contraception. Participants completed a baseline questionnaire that included questions about their history of interpersonal violence and were followed for incident STIs over the 2-year study period. We compared the incidence of STIs in women with and without a history of interpersonal violence using bivariate analyses and multiple logistic regression. Results In the bivariate analyses, STI incidence was found to be significantly associated with African American race/ethnicity, a higher number of sexual partners in the past month, and a lower likelihood of avoidance of sexual partners who pressure to have sex without a condom. In both crude and adjusted regression analyses, time to STI incidence was faster among women who reported physical or sexual abuse in the year before study enrollment (HRRadj = 1.68, 95% CI 1.06, 2.65). Conclusions Women with a recent history of abuse are at significantly increased risk of STI incidence than are nonvictims. PMID:19245303

  17. Vaginal DNA vaccination against infectious diseases transmitted through the vagina.

    Science.gov (United States)

    Kanazawa, Takanori; Takashima, Yuuki; Okada, Hiroaki

    2012-06-01

    There is an urgent need for the development of vaccines against genital virus infections that are transmitted through heterosexual intercourse, including the HIV and HPV. In general, the surface of female genital mucosa, including vaginal mucosa, is the most common site of initiation of these infections. Thus, it is becoming clear that successful vaccines must induce both cellular and humoral immune responses in both the local genital tract and systemically. We believe that a strong vaginal immune response could be obtained by inducing strong gene expression of antigen-coding DNA in the local targeted tissue. In order to improve transfection efficiency in the vagina, it is important that methods allowing breakthrough of the various barriers, such as the epithelial layer, cellular and nuclear membrane, are developed. Therefore, systems providing less invasive and more effective delivery into the subepithelial layer are required. In this review, we will introduce our studies into efficient vaginal DNA vaccination methods, focusing on the effects of the menstrual cycle, utilization of the combination of functional peptides, and use of a needle-free injector.

  18. Disparities in sexually transmitted disease rates across the "eight Americas".

    Science.gov (United States)

    Chesson, Harrell W; Kent, Charlotte K; Owusu-Edusei, Kwame; Leichliter, Jami S; Aral, Sevgi O

    2012-06-01

    The purpose of this study was to examine rates of 3 bacterial sexually transmitted diseases (STDs; syphilis, gonorrhea, and chlamydia) in 8 subpopulations (known as the "eight Americas") defined by race and a small number of county-level sociodemographic and geographical characteristics. The eight Americas are (1) Asians and Pacific Islanders in specific counties; (2) Northland low-income rural white; (3) Middle America; (4) Low-income whites in Appalachia and Mississippi Valley; (5) Western Native American; (6) Black middle America; (7) Southern low-income rural black; and (8) High-risk urban black. A list of the counties comprising each of the eight Americas was obtained from the corresponding author of the original eight Americas project, which examined disparities in mortality rates across the eight Americas. Using county-level STD surveillance data, we calculated syphilis, gonorrhea, and chlamydia rates (new cases per 100,000) for each of the eight Americas. Reported STD rates varied substantially across the eight Americas. STD rates were generally lowest in Americas 1 and 2 and highest in Americas 6, 7, and 8. Although disparities in STDs across the eight Americas are generally similar to the well-established disparities in STDs across race/ethnicity, the grouping of counties into the eight Americas does offer additional insight into disparities in STDs in the United States. The high STD rates we found for black Middle America are consistent with the assertion that sexual networks and social factors are important drivers of racial disparities in STDs.

  19. Prevalence and patterns of HIV transmitted drug resistance in Guatemala.

    Science.gov (United States)

    Avila-Ríos, Santiago; Mejía-Villatoro, Carlos R; García-Morales, Claudia; Soto-Nava, Maribel; Escobar, Ingrid; Mendizabal, Ricardo; Girón, Amalia; García, Leticia; Reyes-Terán, Gustavo

    2011-12-01

    To assess human immunodeficiency virus (HIV) diversity and the prevalence of transmitted drug resistance (TDR) in Guatemala. One hundred forty-five antiretroviral treatment-naïve patients referred to the Roosevelt Hospital in Guatemala City were enrolled from October 2010 to March 2011. Plasma HIV pol sequences were obtained and TDR was assessed with the Stanford algorithm and the World Health Organization (WHO) TDR surveillance mutation list. HIV subtype B was highly prevalent in Guatemala (96.6%, 140/145), and a 2.8% (4/145) prevalence of BF1 recombinants and 0.7% (1/145) prevalence of subtype C viruses were found. TDR prevalence for the study period was 8.3% (12/145) with the Stanford database algorithm (score > 15) and the WHO TDR surveillance mutation list. Most TDR cases were associated with non-nucleoside reverse transcriptase inhibitors (NNRTIs) (83.3%, 10/12); a low prevalence of nucleoside reverse transcriptase inhibitors and protease inhibitors was observed in the cohort (Guatemala. TDR prevalence in Guatemala was at the intermediate level. Most TDR cases were associated with NNRTIs. Further and continuous TDR surveillance is necessary to gain more indepth knowledge about TDR spread and trends in Guatemala and to optimize treatment outcomes in the country.

  20. Trichomoniasis as sexually transmitted disease in sex partners

    Directory of Open Access Journals (Sweden)

    Parvathi C

    1998-01-01

    Full Text Available Study of 30 male consorts of 30 cases of vaginal trichomoniasis with high levels of parasitic infection was undertaken to evaluate the sexually transmitted role of trichomoniasis in sex partners. There were 20 symptomatic and 10 asymptomatic male partners, who revealed T. vaginalis in 80.0% and 60.0 of the cases respectively and the overall prevalence was 73.3% (22 Of 30. T. vaginalis was detected in 83.3% male with urethritis and 50.0% males with prostatitis. Detection of trichomonas in urethral discharge, morning drop secretion, urine deposit and prostatic fluid was 80.0%, 50.0% 35.7% and 21.4% in that order. It is evident from these results that the sex consorts of all cases of trichomoniasis should be considered as harbouring T. vaginalis in their genito-urinary tract as carriers and be treated to break the chain of transmission. Fontanna smear was superior to culture and wet mount in the detection of T. vaginalis, the success rates being 73.3%, 63.3% and 53.3%. A good correlation was observed between smear and culture at high levels of parasitic infection.

  1. The capacity of black holes to transmit quantum information

    International Nuclear Information System (INIS)

    Brádler, Kamil; Adami, Christoph

    2014-01-01

    We study the properties of the quantum information transmission channel that emerges from the quantum dynamics of particles interacting with a black hole horizon. We calculate the quantum channel capacity in two limiting cases where a single-letter capacity is known to exist: the limit of perfectly reflecting and perfectly absorbing black holes. We find that the perfectly reflecting black hole channel is closely related to the Unruh channel and that its capacity is non-vanishing, allowing for the perfect reconstruction of quantum information outside of the black hole horizon. We also find that the complementary channel (transmitting entanglement behind the horizon) is entanglement-breaking in this case, with vanishing capacity. We then calculate the quantum capacity of the black hole channel in the limit of a perfectly absorbing black hole and find that this capacity vanishes, while the capacity of the complementary channel is non-vanishing instead. Rather than inviting a new crisis for quantum physics, this finding instead is in accordance with the quantum no-cloning theorem, because it guarantees that there are no space-like surfaces that contain both the sender’s quantum state and the receiver’s reconstructed quantum state

  2. On the power amplifier nonlinearity in MIMO transmit beamforming systems

    KAUST Repository

    Qi, Jian

    2012-03-01

    In this paper, single-carrier multiple-input multiple-output (MIMO) transmit beamforming (TB) systems in the presence of high-power amplifier (HPA) nonlinearity are investigated. Specifically, due to the suboptimality of the conventional maximal ratio transmission/maximal ratio combining (MRT/MRC) under HPA nonlinearity, we propose the optimal TB scheme with the optimal beamforming weight vector and combining vector, for MIMO systems with nonlinear HPAs. Moreover, an alternative suboptimal but much simpler TB scheme, namely, quantized equal gain transmission (QEGT), is proposed. The latter profits from the property that the elements of the beamforming weight vector have the same constant modulus. The performance of the proposed optimal TB scheme and QEGT/MRC technique in the presence of the HPA nonlinearity is evaluated in terms of the average symbol error probability and mutual information with the Gaussian input, considering the transmission over uncorrelated quasi-static frequency-flat Rayleigh fading channels. Numerical results are provided and show the effects on the performance of several system parameters, namely, the HPA parameters, numbers of antennas, quadrature amplitude modulation modulation order, number of pilot symbols, and cardinality of the beamforming weight vector codebook for QEGT. © 2012 IEEE.

  3. Sex Work Regulation and Sexually Transmitted Infections in Tijuana, Mexico.

    Science.gov (United States)

    Quast, Troy; Gonzalez, Fidel

    2017-05-01

    While reducing the transmission of sexually transmitted infections is a common argument for regulating sex work, relatively little empirical evidence is available regarding the effectiveness of these policies. We investigate the effects of highly publicized sex work regulations introduced in 2005 in Tijuana, Mexico on the incidence of trichomoniasis. State-level, annual data for the 1995-2012 period are employed that include the incidence rates of trichomoniasis by age group and predictor variables. We find that the regulations led to a decrease in the incidence rate of trichomoniasis. Specifically, while our estimates are somewhat noisy, the all-ages incidence rate in the 2005-2012 period is roughly 37% lower than what is predicted by our synthetic control estimates and corresponds to approximately 800 fewer reported cases of trichomoniasis per year. We find that the decreases are especially pronounced for 15-24 and 25-44 age cohorts. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. The role of fear in predicting sexually transmitted infection screening.

    Science.gov (United States)

    Shepherd, Lee; Smith, Michael A

    2017-07-01

    This study assessed the extent to which social-cognitive factors (attitude, subjective norm and perceived control) and the fear of a positive test result predict sexually transmitted infection (STI) screening intentions and subsequent behaviour. Study 1 (N = 85) used a longitudinal design to assess the factors that predict STI screening intention and future screening behaviour measured one month later at Time 2. Study 2 (N = 102) used an experimental design to determine whether the relationship between fear and screening varied depending on whether STI or HIV screening was being assessed both before and after controlling for social-cognitive factors. Across the studies the outcome measures were sexual health screening. In both studies, the fear of having an STI positively predicted STI screening intention. In Study 1, fear, but not the social-cognitive factors, also predicted subsequent STI screening behaviour. In Study 2, the fear of having HIV did not predict HIV screening intention, but attitude negatively and response efficacy positively predicted screening intention. This study highlights the importance of considering the nature of the health condition when assessing the role of fear on health promotion.

  5. Reflection on care in recurrent sexually transmitted co-infections.

    Science.gov (United States)

    Paparello, Joel Zamora; Beyers, Carl; Por, Jitna

    Reflection is a skill that nurses are expected to practise to help them continually re-evaluate their personal effectiveness in problem solving. This skill is necessary when caring for patients who are experiencing the complex challenges linked to psychosexual and psychosociological behavioural changes associated with HIV infection and recurrent sexually transmitted co-infections (STC-I). The Johns model of structured reflection was used in the reflection described here to aid the critical thinking process in helping a nurse to manage and deliver up-to-date, effective care and to develop a strong nurse-patient therapeutic relationship. A holistic approach is key to delivering care to patients with recurrent STC-I. This involves taking a sexual health history and establishing the correct diagnosis, followed by the administration of pharmaceutical and psychotherapeutic treatments to facilitate psychosexual, psychosocial, and psychological changes. This article uses a reflective learning experience in caring for a patient with recurrent STC-I to give insights on psychosexual and psychosociological behavioural strategies. Used with a diagnosis and pharmacological intervention, these strategies can be put into nursing practice and enhance the quality of nursing care.

  6. On Secure NOMA Systems with Transmit Antenna Selection Schemes

    KAUST Repository

    Lei, Hongjiang; Zhang, Jianming; Park, Kihong; Xu, Peng; Ansari, Imran Shafique; Pan, Gaofeng; Alomair, Basel; Alouini, Mohamed-Slim

    2017-01-01

    This paper investigates the secrecy performance of a two-user downlink non-orthogonal multiple access systems. Both single-input and single-output and multiple-input and singleoutput systems with different transmit antenna selection (TAS) strategies are considered. Depending on whether the base station has the global channel state information of both the main and wiretap channels, the exact closed-form expressions for the secrecy outage probability (SOP) with suboptimal antenna selection and optimal antenna selection schemes are obtained and compared with the traditional space-time transmission scheme. To obtain further insights, the asymptotic analysis of the SOP in high average channel power gains regime is presented and it is found that the secrecy diversity order for all the TAS schemes with fixed power allocation is zero. Furthermore, an effective power allocation scheme is proposed to obtain the nonzero diversity order with all the TAS schemes. Monte-Carlo simulations are performed to verify the proposed analytical results.

  7. Haemophilus ducreyi: from sexually transmitted infection to skin ulcer pathogen.

    Science.gov (United States)

    Lewis, David A; Mitjà, Oriol

    2016-02-01

    This article provides an overview of the biology, epidemiology, clinical features, diagnostic tests, and treatment of Haemophilus ducreyi infection, with special reference to the decline of chancroid and the recent emergence of H. ducreyi as a pathogen responsible for chronic limb ulceration clinically similar to yaws. Chancroid has declined in importance as a sexually transmitted infection in most countries where it was previously endemic. Chancroid may be caused by either class I or class II H. ducreyi isolates; these two classes diverged from each other approximately 1.95 million years ago. H. ducreyi has recently emerged as a cause of chronic skin ulceration in the Pacific region and Africa. Based on sequencing of whole genomes and defined genetic loci, it appears that the cutaneous H. ducreyi strains diverged from the class I genital strains relatively recently. H. ducreyi should be considered as a major cause of chronic limb ulceration in both adults and children and appropriate molecular diagnostic assays are required to determine ulcer aetiology. The high prevalence of H. ducreyi-related cutaneous ulceration in yaws-endemic countries has challenged the validity of observational surveys to monitor the effectiveness of the WHO's yaws eradication campaign.

  8. The capacity of black holes to transmit quantum information

    Energy Technology Data Exchange (ETDEWEB)

    Brádler, Kamil [Department of Astronomy and Physics, Saint Mary’s University,Halifax, Nova Scotia, B3H 3C3 (Canada); Adami, Christoph [Department of Physics and Astronomy, Michigan State University,East Lansing, MI 48824 (United States)

    2014-05-21

    We study the properties of the quantum information transmission channel that emerges from the quantum dynamics of particles interacting with a black hole horizon. We calculate the quantum channel capacity in two limiting cases where a single-letter capacity is known to exist: the limit of perfectly reflecting and perfectly absorbing black holes. We find that the perfectly reflecting black hole channel is closely related to the Unruh channel and that its capacity is non-vanishing, allowing for the perfect reconstruction of quantum information outside of the black hole horizon. We also find that the complementary channel (transmitting entanglement behind the horizon) is entanglement-breaking in this case, with vanishing capacity. We then calculate the quantum capacity of the black hole channel in the limit of a perfectly absorbing black hole and find that this capacity vanishes, while the capacity of the complementary channel is non-vanishing instead. Rather than inviting a new crisis for quantum physics, this finding instead is in accordance with the quantum no-cloning theorem, because it guarantees that there are no space-like surfaces that contain both the sender’s quantum state and the receiver’s reconstructed quantum state.

  9. On Secure NOMA Systems with Transmit Antenna Selection Schemes

    KAUST Repository

    Lei, Hongjiang

    2017-08-09

    This paper investigates the secrecy performance of a two-user downlink non-orthogonal multiple access systems. Both single-input and single-output and multiple-input and singleoutput systems with different transmit antenna selection (TAS) strategies are considered. Depending on whether the base station has the global channel state information of both the main and wiretap channels, the exact closed-form expressions for the secrecy outage probability (SOP) with suboptimal antenna selection and optimal antenna selection schemes are obtained and compared with the traditional space-time transmission scheme. To obtain further insights, the asymptotic analysis of the SOP in high average channel power gains regime is presented and it is found that the secrecy diversity order for all the TAS schemes with fixed power allocation is zero. Furthermore, an effective power allocation scheme is proposed to obtain the nonzero diversity order with all the TAS schemes. Monte-Carlo simulations are performed to verify the proposed analytical results.

  10. [Soil transmitted helminthiasis in Argentina. A systematic review].

    Science.gov (United States)

    Socías, M Eugenia; Fernández, Anabel; Gil, José F; Krolewiecki, Alejandro J

    2014-01-01

    A systematic review of surveys performed between 1980 and 2011 (published in MEDLINE/Pubmed and/or LILACS indexed journals, available in the baseline data from a Mass Deworming National Program (MDNP, 2005) was used to identify the prevalence, distribution and detection of risk areas for soil transmitted helminth infections (STH) in Argentina. We found 310 publications in the database using the pre-defined key-words (medical subject headings) for research purposes. Only 24 articles with 26 surveillance sites in 8 provinces and a total of 5495 surveyed individuals fulfilled the inclusion criteria. Frequency rates for STH had a wide range: Ascaris lumbricoides: 0-67%, hookworms: 0-90%, Trichuris trichiura: 0-24.6 and Strongyloides stercoralis: 0-83%. The estimated combined incidence varied from 0.8% to 88.6%. Baseline surveys from the MDNP reporting on 1943 children from 12 provinces confirmed the heterogeneity, with combined STH frequency rates ranging from 0 to 42.7%. Surveys included in this review showed that the distribution of STH in Argentina is not homogeneous, with areas of high incidence (> 20%) in the northeastern and northwestern provinces where mass deworming activities would be highly beneficial. In several surveys, the high overall incidence was mostly due to hookworms and S. stercoralis, a situation to be considered when selecting diagnostic and therapeutic control strategies. The scarcity or absence of data from various provinces and the availability of less than 8000 surveyed individuals should be considered.

  11. [Awareness and education regarding sexually transmitted diseases among undergraduate students].

    Science.gov (United States)

    Castro, Eneida Lazzarini de; Caldas, Tânia Alencar de; Morcillo, André Moreno; Pereira, Elisabete Monteiro de Aguiar; Velho, Paulo Eduardo Neves Ferreira

    2016-06-01

    Sexually transmitted diseases (STDs) are the main global cause of acute illness and death and represent a high socioeconomic cost. Undergraduate students are highly exposed to STDs. The research developed at UNICAMP sought to quantify and generate self-perception of knowledge(or lack thereof) about STDs, as well as evaluate the interest of the students in a course on the topic. The data collection instrument was a questionnaire sent electronically to students about to graduate at the end of 2011 and to freshmen in 2012. The questionnaire was answered by 1,448 seniors and 371 freshmen. Twenty percent of seniors and 38% of freshmen had no sexual activity. Among sexually active students, 26.9% had no regular partner and 28.2% more than two partners per year. The condom was used by 99% of students, but less than 20% used them appropriately. About 80% were unaware that condoms do not provide protection outside the barrier area; they intended to read more about STDs and learnt something about the subject. Nearly half of the students considered that a course should be offered to all undergraduates. These findings will be of use in defining strategies for prevention and the teaching tool could be used in other learning environments.

  12. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Wang Yiyin

    2009-01-01

    Full Text Available Abstract A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR ultra-wideband (UWB system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI and the intersymbol interference (ISI into consideration. Moreover, the bias caused by the interpulse interference (IPI in one frame is also taken into account. Based on the analysis of the stochastic properties of the received signals, several detectors are studied and evaluated. Furthermore, a data-aided two-stage synchronization strategy is proposed, which obtains sample-level timing in the range of one symbol at the first stage and then pursues symbol-level synchronization by looking for the header at the second stage. Three channel estimators are derived to achieve joint channel and timing estimates for the first stage, namely, the linear minimum mean square error (LMMSE estimator, the least squares (LS estimator, and the matched filter (MF. We check the performance of different combinations of channel estimation and equalization schemes and try to find the best combination, that is, the one providing a good tradeoff between complexity and performance.

  13. Digital Receiver Design for Transmitted Reference Ultra-Wideband Systems

    Directory of Open Access Journals (Sweden)

    Yiyin Wang

    2009-01-01

    Full Text Available A complete detection, channel estimation, synchronization, and equalization scheme for a transmitted reference (TR ultra-wideband (UWB system is proposed in this paper. The scheme is based on a data model which admits a moderate data rate and takes both the interframe interference (IFI and the intersymbol interference (ISI into consideration. Moreover, the bias caused by the interpulse interference (IPI in one frame is also taken into account. Based on the analysis of the stochastic properties of the received signals, several detectors are studied and evaluated. Furthermore, a data-aided two-stage synchronization strategy is proposed, which obtains sample-level timing in the range of one symbol at the first stage and then pursues symbol-level synchronization by looking for the header at the second stage. Three channel estimators are derived to achieve joint channel and timing estimates for the first stage, namely, the linear minimum mean square error (LMMSE estimator, the least squares (LS estimator, and the matched filter (MF. We check the performance of different combinations of channel estimation and equalization schemes and try to find the best combination, that is, the one providing a good tradeoff between complexity and performance.

  14. Potential drug development candidates for human soil-transmitted helminthiases.

    Directory of Open Access Journals (Sweden)

    Piero Olliaro

    2011-06-01

    Full Text Available Few drugs are available for soil-transmitted helminthiasis (STH; the benzimidazoles albendazole and mebendazole are the only drugs being used for preventive chemotherapy as they can be given in one single dose with no weight adjustment. While generally safe and effective in reducing intensity of infection, they are contra-indicated in first-trimester pregnancy and have suboptimal efficacy against Trichuris trichiura. In addition, drug resistance is a threat. It is therefore important to find alternatives.We searched the literature and the animal health marketed products and pipeline for potential drug development candidates. Recently registered veterinary products offer advantages in that they have undergone extensive and rigorous animal testing, thus reducing the risk, cost and time to approval for human trials. For selected compounds, we retrieved and summarised publicly available information (through US Freedom of Information (FoI statements, European Public Assessment Reports (EPAR and published literature. Concomitantly, we developed a target product profile (TPP against which the products were compared.The paper summarizes the general findings including various classes of compounds, and more specific information on two veterinary anthelmintics (monepantel, emodepside and nitazoxanide, an antiprotozoal drug, compiled from the EMA EPAR and FDA registration files.Few of the compounds already approved for use in human or animal medicine qualify for development track decision. Fast-tracking to approval for human studies may be possible for veterinary compounds like emodepside and monepantel, but additional information remains to be acquired before an informed decision can be made.

  15. Nudging Armed Groups: How Civilians Transmit Norms of Protection

    Directory of Open Access Journals (Sweden)

    Oliver Kaplan

    2013-12-01

    Full Text Available What are the varying roles that norms play to either enable or constrain violence in armed conflict settings? The article examines this question by drawing on experiences from communities and armed groups in Colombia and Syria. It begins by presenting an explanation of how norms of violence and nonviolence may arise within communities and influence the behavior of civilian residents, reducing the chances of them becoming involved with armed groups. It then considers how civilian communities can transmit those same norms, shared understandings, and patterns of interaction to the ranks of illegal armed groups and subsequently shape their decisions about the use of violence against civilians. The author argues that civilians may be better positioned to promote the principles codified in International Humanitarian Law than international humanitarian organizations because they have closer contact with irregular armed actors and are viewed with greater legitimacy. The analysis illustrates that to better understand civilian protection mechanisms it is essential to study the interactions between communities and armed actors.

  16. Mechanisms and consequences of paternally transmitted chromosomal abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Wyrobek, A J

    2005-04-05

    Paternally transmitted chromosomal damage has been associated with pregnancy loss, developmental and morphological defects, infant mortality, infertility, and genetic diseases in the offspring including cancer. There is epidemiological evidence linking paternal exposure to occupational or environmental agents with an increased risk of abnormal reproductive outcomes. There is also a large body of literature on germ cell mutagenesis in rodents showing that treatment of male germ cells with mutagens has dramatic consequences on reproduction producing effects such as those observed in human epidemiological studies. However, we know very little about the etiology, transmission and early embryonic consequences of paternally-derived chromosomal abnormalities. The available evidence suggests that: (1) there are distinct patterns of germ cell-stage differences in the sensitivity of induction of transmissible genetic damage with male postmeiotic cells being the most sensitive; (2) cytogenetic abnormalities at first metaphase after fertilization are critical intermediates between paternal exposure and abnormal reproductive outcomes; and, (3) there are maternally susceptibility factors that may have profound effects on the amount of sperm DNA damage that is converted into chromosomal aberrations in the zygote and directly affect the risk for abnormal reproductive outcomes.

  17. EPA-Registered Repellents for Mosquitoes Transmitting Emerging Viral Disease.

    Science.gov (United States)

    Patel, Radha V; Shaeer, Kristy M; Patel, Pooja; Garmaza, Aleksey; Wiangkham, Kornwalee; Franks, Rachel B; Pane, Olivia; Carris, Nicholas W

    2016-12-01

    In many parts of the United States, mosquitoes were previously nuisance pests. However, they now represent a potential threat in the spread of viral diseases. The Aedes aegypti, Aedes albopictus, and Culex species mosquitoes are endemic to the United States and together may transmit a variety of viral diseases of growing concern, including West Nile virus, chikungunya, dengue fever, and Zika virus. The Centers for Disease Control and Prevention and the Environmental Protection Agency (EPA) recommend N,N-diethyl-meta-toluamide (DEET) as a first-line mosquito repellent, but for patients refusing to use DEET or other conventional repellents, guidance is limited to any EPA-registered product. Therefore, we conducted a systematic review of the literature to identify which EPA-registered personal mosquito repellent provides the best protection from A. aegypti, A. albopictus, and Culex spp. mosquitoes. We abstracted data from 62 published reports of EPA-registered mosquito repellents. The conventional repellent picaridin has the strongest data to support its use as a second-line agent, while IR3535 and oil of lemon eucalyptus are reasonably effective natural products. Citronella, catnip, and 2-undecanone offer limited protection or have limited data. These results can be used by pharmacists and other health care professionals to advise patients on the selection of an EPA-registered mosquito repellent. Regardless of the repellent chosen, it is vital for patients to follow all instructions/precautions in the product labeling to ensure safe and effective use. © 2016 Pharmacotherapy Publications, Inc.

  18. Aerosols transmit prions to immunocompetent and immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Johannes Haybaeck

    Full Text Available Prions, the agents causing transmissible spongiform encephalopathies, colonize the brain of hosts after oral, parenteral, intralingual, or even transdermal uptake. However, prions are not generally considered to be airborne. Here we report that inbred and crossbred wild-type mice, as well as tga20 transgenic mice overexpressing PrP(C, efficiently develop scrapie upon exposure to aerosolized prions. NSE-PrP transgenic mice, which express PrP(C selectively in neurons, were also susceptible to airborne prions. Aerogenic infection occurred also in mice lacking B- and T-lymphocytes, NK-cells, follicular dendritic cells or complement components. Brains of diseased mice contained PrP(Sc and transmitted scrapie when inoculated into further mice. We conclude that aerogenic exposure to prions is very efficacious and can lead to direct invasion of neural pathways without an obligatory replicative phase in lymphoid organs. This previously unappreciated risk for airborne prion transmission may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories.

  19. On the power amplifier nonlinearity in MIMO transmit beamforming systems

    KAUST Repository

    Qi, Jian; Aissa, Sonia

    2012-01-01

    In this paper, single-carrier multiple-input multiple-output (MIMO) transmit beamforming (TB) systems in the presence of high-power amplifier (HPA) nonlinearity are investigated. Specifically, due to the suboptimality of the conventional maximal ratio transmission/maximal ratio combining (MRT/MRC) under HPA nonlinearity, we propose the optimal TB scheme with the optimal beamforming weight vector and combining vector, for MIMO systems with nonlinear HPAs. Moreover, an alternative suboptimal but much simpler TB scheme, namely, quantized equal gain transmission (QEGT), is proposed. The latter profits from the property that the elements of the beamforming weight vector have the same constant modulus. The performance of the proposed optimal TB scheme and QEGT/MRC technique in the presence of the HPA nonlinearity is evaluated in terms of the average symbol error probability and mutual information with the Gaussian input, considering the transmission over uncorrelated quasi-static frequency-flat Rayleigh fading channels. Numerical results are provided and show the effects on the performance of several system parameters, namely, the HPA parameters, numbers of antennas, quadrature amplitude modulation modulation order, number of pilot symbols, and cardinality of the beamforming weight vector codebook for QEGT. © 2012 IEEE.

  20. Effect of Window Glazing on Colour Quality of Transmitted Daylight

    Directory of Open Access Journals (Sweden)

    Rajendra Dangol

    2017-12-01

    Full Text Available In this study, the colour quality of the daylight transmitted through different window glazing types is evaluated. The analysis considered four different types of window glazing: laminated, monolithic, coated and applied film glazing ranging in luminous transmittance from around 0.97 to <0.1. The spectral transmittance data of different window glazing types are taken from the International Glazing Data Base (IGDB, which is maintained by Lawrence Berkeley National Laboratories (LBNL. The study showed that the CIE CRI does not always seem to be the suitable method to predict the colour quality of daylight in building for particular situations. However, in the context of this study, the prediction of colour rendering properties of window glazing by other metrics such as Colour Quality Scale (version 9, Memory CRI, Ra,D65 (adjusted CRI metric with D65 as the reference illuminant performed better. For most of the daylit situations inside the building, the chromaticity difference criterion was not met. Judging the colour quality of such situations requires different method.

  1. Prevalence of Sexually Transmitted Infection in Teenage Pregnancy in Rajavithi Hospital, Thailand.

    Science.gov (United States)

    Asavapiriyanont, Suvanna; Chaovarindr, Udom; Kaoien, Surasak; Chotigeat, Uraiwan; Kovavisarach, Ekachai

    2016-02-01

    Behavioral and social changes in the modern era have triggered an increase in the incidence of early sexual contact and teenage pregnancy. Since there is no routine Gonococcal & Chlamydial (GC & CT) screening in teens in antenatal clinics in Thailand, the present study was performed to find the prevalence of STI, especially Chlamydial infection, in teenage pregnancy. To evaluate the prevalence of sexually transmitted infections (STIs), especially Chlamydial infection (CT), in teenage pregnancy and its related factors. One hundred and twenty-one teenage pregnancies were recruited at the ANC in Rajavithi Hospital from October 2006 to May 2007. After signing informed consent forms, they were asked to answer questionnaires about baseline data, sexual information and risk factors, after which urine specimens were collected for screening for GC and CT using the PCR technique (AMPLICOR by Roche). Later, pelvic examination was per formed by the gynecologist at the STD (sexually transmitted disease) clinic. All the data and LAB results were recorded and analyzed by the SPSS program. Numbers, percentages, means with SD, Chi-squared test, Fisher's exact test and odds ratio were used. Potential risk factors were analyzed using binary logistic regression. The prevalence of STI in pregnant teenagers was 28.1% (CT = 19.8%, GC = 1.7%, hepatitis B = 3.3%, trichomoniasis 1.7%, Herpes simplex = 0.8% and condyloma acuminata = 0.8%). No Syphilis, chancroid or HIV were found in the present study Other non-STI like candidiasis and bacterial vaginosis were found in 45.5% of participants (candidiasis and bacterial vaginosis at 19.0% and 24.8%, respectively). The risk of CT infection was significantly related (6.9 times higher) to having previous sexual contact before the current partner (95% CI, 1.8-27.0). STI, especially Chlamydial infection, was found in a significant number of teenage pregnancies. Measures should be taken to prevent this resulting in complicated outcomes in the future.

  2. Gene-expression analysis of cold-stress response in the sexually transmitted protist Trichomonas vaginalis.

    Science.gov (United States)

    Fang, Yi-Kai; Huang, Kuo-Yang; Huang, Po-Jung; Lin, Rose; Chao, Mei; Tang, Petrus

    2015-12-01

    Trichomonas vaginalis is the etiologic agent of trichomoniasis, the most common nonviral sexually transmitted disease in the world. This infection affects millions of individuals worldwide annually. Although direct sexual contact is the most common mode of transmission, increasing evidence indicates that T. vaginalis can survive in the external environment and can be transmitted by contaminated utensils. We found that the growth of T. vaginalis under cold conditions is greatly inhibited, but recovers after placing these stressed cells at the normal cultivation temperature of 37 °C. However, the mechanisms by which T. vaginalis regulates this adaptive process are unclear. An expressed sequence tag (EST) database generated from a complementary DNA library of T. vaginalis messenger RNAs expressed under cold-culture conditions (4 °C, TvC) was compared with a previously published normal-cultured EST library (37 °C, TvE) to assess the cold-stress responses of T. vaginalis. A total of 9780 clones were sequenced from the TvC library and were mapped to 2934 genes in the T. vaginalis genome. A total of 1254 genes were expressed in both the TvE and TvC libraries, and 1680 genes were only found in the TvC library. A functional analysis showed that cold temperature has effects on many cellular mechanisms, including increased H2O2 tolerance, activation of the ubiquitin-proteasome system, induction of iron-sulfur cluster assembly, and reduced energy metabolism and enzyme expression. The current study is the first large-scale transcriptomic analysis in cold-stressed T. vaginalis and the results enhance our understanding of this important protist. Copyright © 2014. Published by Elsevier B.V.

  3. Accurate modeling and maximum power point detection of ...

    African Journals Online (AJOL)

    Accurate modeling and maximum power point detection of photovoltaic ... Determination of MPP enables the PV system to deliver maximum available power. ..... adaptive artificial neural network: Proposition for a new sizing procedure.

  4. Maximum power per VA control of vector controlled interior ...

    Indian Academy of Sciences (India)

    Thakur Sumeet Singh

    2018-04-11

    Apr 11, 2018 ... Department of Electrical Engineering, Indian Institute of Technology Delhi, New ... The MPVA operation allows maximum-utilization of the drive-system. ... Permanent magnet motor; unity power factor; maximum VA utilization; ...

  5. The Kalman Filter Revisited Using Maximum Relative Entropy

    Directory of Open Access Journals (Sweden)

    Adom Giffin

    2014-02-01

    Full Text Available In 1960, Rudolf E. Kalman created what is known as the Kalman filter, which is a way to estimate unknown variables from noisy measurements. The algorithm follows the logic that if the previous state of the system is known, it could be used as the best guess for the current state. This information is first applied a priori to any measurement by using it in the underlying dynamics of the system. Second, measurements of the unknown variables are taken. These two pieces of information are taken into account to determine the current state of the system. Bayesian inference is specifically designed to accommodate the problem of updating what we think of the world based on partial or uncertain information. In this paper, we present a derivation of the general Bayesian filter, then adapt it for Markov systems. A simple example is shown for pedagogical purposes. We also show that by using the Kalman assumptions or “constraints”, we can arrive at the Kalman filter using the method of maximum (relative entropy (MrE, which goes beyond Bayesian methods. Finally, we derive a generalized, nonlinear filter using MrE, where the original Kalman Filter is a special case. We further show that the variable relationship can be any function, and thus, approximations, such as the extended Kalman filter, the unscented Kalman filter and other Kalman variants are special cases as well.

  6. Savannah River Site radioiodine atmospheric releases and offsite maximum doses

    International Nuclear Information System (INIS)

    Marter, W.L.

    1990-01-01

    Radioisotopes of iodine have been released to the atmosphere from the Savannah River Site since 1955. The releases, mostly from the 200-F and 200-H Chemical Separations areas, consist of the isotopes, I-129 and 1-131. Small amounts of 1-131 and 1-133 have also been released from reactor facilities and the Savannah River Laboratory. This reference memorandum was issued to summarize our current knowledge of releases of radioiodines and resultant maximum offsite doses. This memorandum supplements the reference memorandum by providing more detailed supporting technical information. Doses reported in this memorandum from consumption of the milk containing the highest I-131 concentration following the 1961 1-131 release incident are about 1% higher than reported in the reference memorandum. This is the result of using unrounded 1-131 concentrations of I-131 in milk in this memo. It is emphasized here that this technical report does not constitute a dose reconstruction in the same sense as the dose reconstruction effort currently underway at Hanford. This report uses existing published data for radioiodine releases and existing transport and dosimetry models

  7. New algorithm using only one variable measurement applied to a maximum power point tracker

    Energy Technology Data Exchange (ETDEWEB)

    Salas, V.; Olias, E.; Lazaro, A.; Barrado, A. [University Carlos III de Madrid (Spain). Dept. of Electronic Technology

    2005-05-01

    A novel algorithm for seeking the maximum power point of a photovoltaic (PV) array for any temperature and solar irradiation level, needing only the PV current value, is proposed. Satisfactory theoretical and experimental results are presented and were obtained when the algorithm was included on a 100 W 24 V PV buck converter prototype, using an inexpensive microcontroller. The load of the system used was a battery and a resistance. The main advantage of this new maximum power point tracking (MPPT), when is compared with others, is that it only uses the measurement of the photovoltaic current, I{sub PV}. (author)

  8. 40 CFR 141.13 - Maximum contaminant levels for turbidity.

    Science.gov (United States)

    2010-07-01

    ... turbidity. 141.13 Section 141.13 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Maximum contaminant levels for turbidity. The maximum contaminant levels for turbidity are applicable to... part. The maximum contaminant levels for turbidity in drinking water, measured at a representative...

  9. Maximum Power Training and Plyometrics for Cross-Country Running.

    Science.gov (United States)

    Ebben, William P.

    2001-01-01

    Provides a rationale for maximum power training and plyometrics as conditioning strategies for cross-country runners, examining: an evaluation of training methods (strength training and maximum power training and plyometrics); biomechanic and velocity specificity (role in preventing injury); and practical application of maximum power training and…

  10. 13 CFR 107.840 - Maximum term of Financing.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Maximum term of Financing. 107.840... COMPANIES Financing of Small Businesses by Licensees Structuring Licensee's Financing of An Eligible Small Business: Terms and Conditions of Financing § 107.840 Maximum term of Financing. The maximum term of any...

  11. 7 CFR 3565.210 - Maximum interest rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Maximum interest rate. 3565.210 Section 3565.210... AGRICULTURE GUARANTEED RURAL RENTAL HOUSING PROGRAM Loan Requirements § 3565.210 Maximum interest rate. The interest rate for a guaranteed loan must not exceed the maximum allowable rate specified by the Agency in...

  12. Characterizing graphs of maximum matching width at most 2

    DEFF Research Database (Denmark)

    Jeong, Jisu; Ok, Seongmin; Suh, Geewon

    2017-01-01

    The maximum matching width is a width-parameter that is de ned on a branch-decomposition over the vertex set of a graph. The size of a maximum matching in the bipartite graph is used as a cut-function. In this paper, we characterize the graphs of maximum matching width at most 2 using the minor o...

  13. Current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Loescher, D.H. [Sandia National Labs., Albuquerque, NM (United States). Systems Surety Assessment Dept.; Noren, K. [Univ. of Idaho, Moscow, ID (United States). Dept. of Electrical Engineering

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  14. Quantities of natural gas transmitted in January-December 2012. Quantities of natural gas transported in January-December 2012

    International Nuclear Information System (INIS)

    2013-01-01

    GRTgaz is a European leader in natural gas transmission, a world expert in gas transmission networks and systems, and an operator firmly committed to the energy transition. It owns and operates the gas transmission network throughout most of France and it manages the transmission network in Germany, thereby helping to ensure correct operation of the French and European gas market. It contributes to the energy security of regional supply systems and performs a public service mission to ensure the continuity of consumer supply. This document presents the monthly key figures of GRTgaz activity in 2012: Total quantities transmitted by GRTgaz (Inputs to the GRTgaz network/Outputs from the GRTgaz network); Maximum and minimum daily flow (Daily quantities transported, Daily consumption, Daily inputs excluding storage); Quantities exchanged on the wholesale market; Consumption on the GRTgaz Network (gross monthly consumption and Average monthly temperatures)

  15. Dynamic of microwave breakdown in the localized places of transmitting line driving by Cherenkov-type oscillator

    Science.gov (United States)

    Xie, Jialing; Chen, Changhua; Chang, Chao; Wu, Cheng; Shi, Yanchao; Cao, Yibing; Song, Zhimin; Zhang, Yuchuan

    2018-02-01

    A breakdown cavity is designed to study the breakdown phenomena of high-power microwaves in transmission waveguides. The maximum electric field within the cavity varies in amplitude from 400 kV/cm to 1.8 MV/cm and may surpass breakdown thresholds. The breakdown cavities were studied in particle-in-cell simulations and experiments, the results of which yielded waveforms that were consistent. The experimental results indicate that the microwave pulse does not shorten, and the amplitude of the electric field does not fall below 800 kV/cm. Moreover, large numbers of electrons are not emitted in microwaves below 670 kV/cm at 9.75 GHz frequency and 25-ns pulse width transmitted in stainless steel waveguides. The radiation waveforms of breakdown cavity with different materials are compared in experiments, with titanium material performing better.

  16. Simultaneous maximum a posteriori longitudinal PET image reconstruction

    Science.gov (United States)

    Ellis, Sam; Reader, Andrew J.

    2017-09-01

    Positron emission tomography (PET) is frequently used to monitor functional changes that occur over extended time scales, for example in longitudinal oncology PET protocols that include routine clinical follow-up scans to assess the efficacy of a course of treatment. In these contexts PET datasets are currently reconstructed into images using single-dataset reconstruction methods. Inspired by recently proposed joint PET-MR reconstruction methods, we propose to reconstruct longitudinal datasets simultaneously by using a joint penalty term in order to exploit the high degree of similarity between longitudinal images. We achieved this by penalising voxel-wise differences between pairs of longitudinal PET images in a one-step-late maximum a posteriori (MAP) fashion, resulting in the MAP simultaneous longitudinal reconstruction (SLR) method. The proposed method reduced reconstruction errors and visually improved images relative to standard maximum likelihood expectation-maximisation (ML-EM) in simulated 2D longitudinal brain tumour scans. In reconstructions of split real 3D data with inserted simulated tumours, noise across images reconstructed with MAP-SLR was reduced to levels equivalent to doubling the number of detected counts when using ML-EM. Furthermore, quantification of tumour activities was largely preserved over a variety of longitudinal tumour changes, including changes in size and activity, with larger changes inducing larger biases relative to standard ML-EM reconstructions. Similar improvements were observed for a range of counts levels, demonstrating the robustness of the method when used with a single penalty strength. The results suggest that longitudinal regularisation is a simple but effective method of improving reconstructed PET images without using resolution degrading priors.

  17. Surveillance of transmitted HIV drug resistance in antiretroviral-naive patients aged less than 25 years, in Bangkok, Thailand.

    Science.gov (United States)

    Sungkanuparph, Somnuek; Pasomsub, Ekawat; Chantratita, Wasun

    2014-01-01

    Emergence of transmitted HIV drug resistance (TDR) is a concern after global scale-up of antiretroviral therapy (ART). World Health Organization had developed threshold survey method for surveillance of TDR in resource-limited countries. ART in Thailand has been scaling up for >10 years. To evaluate the current TDR in Thailand, a cross-sectional study was conducted among antiretroviral-naive HIV-infected patients aged Thailand after a decade of rapid scale-up of ART. Interventions to prevent TDR at the population level are essentially needed in Thailand. Surveillance for TDR in Thailand has to be regularly performed.

  18. Spin current

    CERN Document Server

    Valenzuela, Sergio O; Saitoh, Eiji; Kimura, Takashi

    2017-01-01

    Since the discovery of the giant magnetoresistance effect in magnetic multilayers in 1988, a new branch of physics and technology, called spin-electronics or spintronics, has emerged, where the flow of electrical charge as well as the flow of electron spin, the so-called “spin current,” are manipulated and controlled together. The physics of magnetism and the application of spin current have progressed in tandem with the nanofabrication technology of magnets and the engineering of interfaces and thin films. This book aims to provide an introduction and guide to the new physics and applications of spin current, with an emphasis on the interaction between spin and charge currents in magnetic nanostructures.

  19. Novel methods for estimating lithium-ion battery state of energy and maximum available energy

    International Nuclear Information System (INIS)

    Zheng, Linfeng; Zhu, Jianguo; Wang, Guoxiu; He, Tingting; Wei, Yiying

    2016-01-01

    Highlights: • Study on temperature, current, aging dependencies of maximum available energy. • Study on the various factors dependencies of relationships between SOE and SOC. • A quantitative relationship between SOE and SOC is proposed for SOE estimation. • Estimate maximum available energy by means of moving-window energy-integral. • The robustness and feasibility of the proposed approaches are systematic evaluated. - Abstract: The battery state of energy (SOE) allows a direct determination of the ratio between the remaining and maximum available energy of a battery, which is critical for energy optimization and management in energy storage systems. In this paper, the ambient temperature, battery discharge/charge current rate and cell aging level dependencies of battery maximum available energy and SOE are comprehensively analyzed. An explicit quantitative relationship between SOE and state of charge (SOC) for LiMn_2O_4 battery cells is proposed for SOE estimation, and a moving-window energy-integral technique is incorporated to estimate battery maximum available energy. Experimental results show that the proposed approaches can estimate battery maximum available energy and SOE with high precision. The robustness of the proposed approaches against various operation conditions and cell aging levels is systematically evaluated.

  20. [Waterborne outbreak of gastroenteritis transmitted through the public water supply].

    Science.gov (United States)

    Godoy, P; Borrull, C; Palà, M; Caubet, I; Bach, P; Nuín, C; Espinet, L; Torres, J; Mirada, G

    2003-01-01

    The chlorination of public water supplies has led researchers to largely discard drinking water as a potential source of gastroenteritis outbreaks. The aim of this study was to investigate an outbreak of waterborne disease associated with drinking water from public supplies. A historical cohort study was carried out following notification of a gastroenteritis outbreak in Baqueira (Valle de Arán, Spain). We used systematic sampling to select 87 individuals staying at hotels and 67 staying in apartments in the target area. Information was gathered on four factors (consumption of water from the public water supply, sandwiches, water and food in the ski resorts) as well as on symptoms. We assessed residual chlorine in drinking water, analyzed samples of drinking water, and studied stool cultures from 4 patients. The risk associated with each water source and food type was assessed by means of relative risk (RR) and 95% confidence intervals (CI). The overall attack rate was 51.0% (76/149). The main symptoms were diarrhea 87.5%, abdominal pain 80.0%, nausea 50.7%, vomiting 30.3%, and fever 27.0%. The only factor associated with a statistically significant risk of disease was consumption of drinking water (RR = 11.0; 95% CI, 1.6-74.7). No residual chlorine was detected in the drinking water, which was judged acceptable. A problem associated with the location of the chlorinator was observed and corrected. We also recommended an increase in chlorine levels, which was followed by a reduction in the number of cases. The results of stool cultures of the four patients were negative for enterobacteria. This study highlights the potential importance of waterborne outbreaks of gastroenteritis transmitted through drinking water considered acceptable and suggests the need to improve microbiological research into these outbreaks (viruses and protozoa detection).

  1. Observations of sexually transmitted disease consultations in India.

    Science.gov (United States)

    Mertens, T E; Smith, G D; Kantharaj, K; Mugrditchian, D; Radhakrishnan, K M

    1998-03-01

    To assess the quality of sexually transmitted disease (STD) case management provided in public and private health facilities in selected areas of Madras, Tamil Nadu, India, in order to make recommendations for improving the quality of care and promote the syndromic approach to STD treatment. Structured observations of consultations for STDs in health care facilities. Scoring of the observations according to standards for history taking, examination, treatment and provision of basic health promotion advice allows evaluation of STD case management. With STD treatment adequacy scored against Indian national guidelines (which recommend aetiologic treatment), history taking, examination and treatment were satisfactory in 76 out of 108 (70%) of observed consultations. However, if STD treatment adequacy is scored with respect to the syndrome approach towards selected STD (male urethritis and non herpetic genital ulcer for both sexes), only 8 out of 81 (10%) of the patients were satisfactory managed. During 32 out of 108 (30%) of the consultations, advice on the use of condoms in order to prevent STD or HIV/AIDS was given. Instructions regarding how to use condoms were offered to seven (6%) patients and condoms were only provided to one patient (1%). Patients were urged to refer their partner(s) for treatment during 29 (27%) of consultations. A criterion of adequate use of the STD consultation for health promotion, requiring both promotion of condoms and encouragement to refer partner(s) for treatment, was met during 13 (12%) of consultations. Monitoring and improving the standards of care at facilities at which STDs are treated have become key roles of STD/HIV/AIDS programmes. The present report suggests that in Madras the activities of medical practitioners who treat STD patients are far from ideal at present. Improvements would involve simplifying existing treatment guidelines by promoting the syndromic approach to STD management, continuing education programmes for

  2. Sexually Transmitted Infections (STIs among young adult in Italy

    Directory of Open Access Journals (Sweden)

    Maria Cristina Salfa

    2010-12-01

    Full Text Available Sexually transmitted infections (STIs include a large group of widespread infectious diseases, which may cause acute symptoms, chronic infections and severe long term complications.The control and prevention of these infections are public health priorities for several reasons: • the large number of people that acquire an STI per year; • the major proportion of asymptomatic infected individuals; • the high circulation in patients with sexual risk behavior (young adults, pluripartner, men who have sex with men, foreigners, commercial sex workers; • increased biological susceptibility of some subjects, such as young adults (immature genital tissues and more receptive to pathogens, women (genital apparatus more complex and extended in which pathogens are more likely to settle, or individuals carrying states of severe immunodeficiency; • the serious complications in the event of failure or incorrect diagnosis and treatment (chronic disease, infertility, oncogenic transformation, synergy with HIV infection; • the possibility of preventing and treating many of these infections. Therefore, recent guidelines from international agencies have recommended countries from the European Union to improve epidemiological STI surveillance systems in order to standardize data collection to facilitate their comparability between different geographical areas and to improve the information flow for faster tracking of the impact; furthermore, to extend surveillance to widespread, but often asymptomatic, disease (e.g. Chlamydia trachomatis, to conduct behavioural surveillance in patients with STIs, to increase public awareness of the role of STIs in the transmission/acquisition of HIV, and to increase the commitment of institutions in the prevention and control of STIs.

  3. Improving sexually transmitted infection results notification via mobile phone technology.

    Science.gov (United States)

    Reed, Jennifer L; Huppert, Jill S; Taylor, Regina G; Gillespie, Gordon L; Byczkowski, Terri L; Kahn, Jessica A; Alessandrini, Evaline A

    2014-11-01

    To improve adolescent notification of positive sexually transmitted infection (STI) tests using mobile phone technology and STI information cards. A randomized intervention among 14- to 21-year olds in a pediatric emergency department (PED). A 2 × 3 factorial design with replication was used to evaluate the effectiveness of six combinations of two factors on the proportion of STI-positive adolescents notified within 7 days of testing. Independent factors included method of notification (call, text message, or call + text message) and provision of an STI information card with or without a phone number to obtain results. Covariates for logistic regression included age, empiric STI treatment, days until first attempted notification, and documentation of confidential phone number. Approximately half of the 383 females and 201 males enrolled were ≥18 years of age. Texting only or type of card was not significantly associated with patient notification rates, and there was no significant interaction between card and notification method. For females, successful notification was significantly greater for call + text message (odds ratio, 3.2; 95% confidence interval, 1.4-6.9), and documenting a confidential phone number was independently associated with successful notification (odds ratio, 3.6; 95% confidence interval, 1.7-7.5). We found no significant predictors of successful notification for males. Of patients with a documented confidential phone number who received a call + text message, 94% of females and 83% of males were successfully notified. Obtaining a confidential phone number and using call + text message improved STI notification rates among female but not male adolescents in a pediatric emergency department. Copyright © 2014 Society for Adolescent Health and Medicine. All rights reserved.

  4. AABB Committee Report: reducing transfusion-transmitted cytomegalovirus infections.

    Science.gov (United States)

    Heddle, Nancy M; Boeckh, Michael; Grossman, Brenda; Jacobson, Jessica; Kleinman, Steven; Tobian, Aaron A R; Webert, Kathryn; Wong, Edward C C; Roback, John D

    2016-06-01

    Transfusion-transmitted cytomegalovirus (TT-CMV) is often asymptomatic, but certain patient populations, such as very low birth weight neonates, fetuses requiring intrauterine transfusion, pregnant women, patients with primary immunodeficiencies, transplant recipients, and patients receiving chemotherapy or transplantation for malignant disease, may be at risk of life-threatening CMV infection. It is unclear whether leukoreduction of cellular blood components is sufficient to reduce TT-CMV or whether CMV serological testing adds additional benefit to leukoreduction. The AABB CMV Prevention Work Group commissioned a systematic review to address these issues and subsequently develop clinical practice guidelines. However, the data were of poor quality, and no studies of significant size have been performed for over a decade. Rather than creating guidelines of questionable utility, the Work Group (with approval of the AABB Board of Directors) voted to prepare this Committee Report. There is wide variation in practices of using leukoreduced components alone or combining CMV-serology and leukoreduction to prevent TT-CMV for at-risk patients. Other approaches may also be feasible to prevent TT-CMV, including plasma nucleic acid testing, pathogen inactivation, and patient blood management programs to reduce the frequency of inappropriate transfusions. It is unlikely that future large-scale clinical trials will be performed to determine whether leukoreduction, CMV-serology, or a combination of both is superior. Consequently, alternative strategies including pragmatic randomized controlled trials, registries, and collaborations for electronic data merging, nontraditional approaches to inform evidence, or development of a systematic approach to inform expert opinion may help to address the issue of CMV-safe blood components. © 2016 AABB.

  5. Screening for Sexually Transmitted Infection Pathogens in Semen Samples

    Directory of Open Access Journals (Sweden)

    RW Peeling

    2005-01-01

    Full Text Available The transmission of sexually transmitted infection (STI pathogens from an infected donor to the recipient of a semen donation in assisted conception may result not only in acute infection but also in long-term reproductive complications or adverse outcomes of pregnancy, including infection of the offspring. Screening for bacterial STI pathogens, Chlamydia trachomatis and Neisseria gonorrhoeae is strongly recommended because these pathogens can cause serious reproductive complications in the recipients of semen donations and infection in their offspring. Screening for these pathogens should be performed using the most sensitive methods, such as nucleic acid amplified tests. False-negative results due to inhibitory substances in the semen sample should be monitored using amplification controls. Where specimen transport is not a problem and culture facilities are available, N gonorrhoeae can also be detected by culture. Laboratories performing screening should subscribe to proficiency programs and have strict quality controls. Although Trichomonas vaginalis, group B streptococcus and genital mycoplasmas have been associated with adverse outcomes of pregnancy, the frequent finding of these organisms in healthy individuals brings into question the validity of mandatory inclusion of these organisms in the screening panel. Although viral STI pathogens and Treponema pallidum -- the causative agent of syphilis -- may be detected in semen, their presence may be more sensitively detected through antibody testing of the donor. Screening donors for HIV, hepatitis B and syphilis by serology is uniformly recommended in all of the guidelines, but the value of screening either donors or semen samples for cytomegalovirus, herpes simplex viruses and human papilloma viruses is less clear.

  6. Diagnosis of vascular injuries caused by hand-transmitted vibration.

    Science.gov (United States)

    Harada, N; Mahbub, M H

    2008-04-01

    For a reliable objective diagnosis of vascular injuries in hand-arm vibration syndrome (HAVS), the standardized cold provocation tests--finger skin temperature measurement during hand(s) immersion in cold water (FST test) and finger systolic blood pressure measurement during local cold exposure (FSBP test)--are widely used. In recent years there is a growing controversy regarding the diagnostic value of these tests. The aim of this study was to describe particularly the diagnostic performance of FST and FSBP tests, and also to focus on the problems and uncertainties regarding the test conditions and results, in the laboratory diagnosis of vascular injuries caused by hand-transmitted vibration. A review of pertinent published English- and Japanese-language articles and conference proceedings (between 1976 and 2006) was conducted. From the reports with regard to diagnostic significance of the FSBP test, it seems to be an important laboratory test for diagnosing vibration-induced white finger (VWF). On the other hand, despite a large number of research studies with the FST test, there is a lack of data for the standardized FST test, which can confirm the value of it in diagnosing VWF. Moreover, there is no agreement on effective parameter/s to quantify and compare the responses in FST induced by immersion in cold water. While assessing and staging vascular injuries in HAVS, inquiry regarding finger coldness appears to be useful. As there is no single test with satisfactory diagnostic ability for VWF, at present it is reasonable to use the cold provocation tests as a part of the comprehensive approach to evaluate HAVS patients. In addition to the objective methods, the index of finger coldness may be useful while diagnosing the vascular component of HAVS.

  7. Parental perspectives on vaccinating children against sexually transmitted infections.

    Science.gov (United States)

    Mays, Rose M; Sturm, Lynne A; Zimet, Gregory D

    2004-04-01

    Several vaccines for sexually transmitted infections (STI) are presently in development and the eventual availability of such vaccines is expected to result in the prevention of a significant number of burdensome conditions. Young adolescents are presumed to be likely targets for these vaccines since adolescents' risk for STI increases as they age and become sexually active. It is unclear, however, to what extent parents will agree to having adolescents receive STI vaccines. Inasmuch as acceptance is the foundation for effective immunization programs, an understanding of parental perspectives about this issue is required to inform future STI vaccine program strategies. This paper presents findings from a qualitative study that used in-depth interviews to elicit attitudes from 34 parents about accepting vaccines for genital herpes, human immunodeficiency virus, human papillomavirus and gonorrhea for their children (aged 8-17). Data were collected from parents bringing their children for care at an urban clinic and a suburban private office. Content analysis of the responses revealed that most parents (>70%) approved the administration of all four of the STI vaccines proposed. Parents' reasons for acceptance included wanting to protect their children, being concerned about specific disease characteristics, and previous experience with the infections. Parents who declined the vaccines did so primarily because they perceived their children to be at low risk for the infections or they had low concern about features of the diseases. Most parents thought they should be the decision-maker regarding children receiving an STI vaccine. Results from this study will be used to plan subsequent investigations of the determinants of STI vaccine acceptance by parents.

  8. Frequency of sexually transmitted diseases and main methodological implications

    Directory of Open Access Journals (Sweden)

    Zaleida Napoli

    2013-08-01

    Full Text Available Background. High risk Human Papillomavirus (HR-HPV persistence is the most important cervical cancer risk factor, while Chlamydia trachomatis (CT, Neisseria gonorrhoeae (NG, Mycoplasma hominis (MH, Mycoplasma genitalium(MG, Ureaplasma urealyticum (UU and parvum (UP are sexually transmitted diseases (STDs causing infertility, pregnancy complication, lung problems in newborns. Methods. 135 urine, 135 urethral swabs, 553 cervical swabs, 110 seminal fluids and 1440 Thin Prep, were tested with culture methods, Real-Time PCR (RT-PCR and multiplex SYBR Green PCR-endpoint to detect STDs. PCR- endpoint was performed to detect HPV. Results. Culture methods showed the lowest sensitivity: for MH it was only 24% (compared to RT-PCR. UP/UU were the most frequent pathogens (13% with culture, 29% with PCR-endpoint, 41,67% with RT-PCR. Turn Around Time was respectively: 48h, 6h and 2h. RT-PCR cervical frequencies for CT, MH, MG, UU, UP were: 5.42%, 11.03%, 1.81%, 11.21% and 35.08%. HPV positivity in primary and secondary screening was 17.33% and 51.14%. Highes t positivity age group was: 23-32 years for CT (17%, and 18-27 years for HPV (33%. Conclusions. RT-PCR is more sensitive, faster, less expensive than other molecular tests like PCR-endpoint and microarrays. It allows more efficient laboratory organization: pre-analytical phase is more automated and enable the implementation of further diagnostic tests for pathologies that need rapid identification, such as meningitidis and sepsis, with reduced human and instrumental resource. Regarding STDs screening, it should be performed in women: for CT at least up to 27 years; for HPV between 35-50 years, since persisting HR-HPV infection is responsible of high-grade lesions.

  9. Evolution of the apomixis transmitting chromosome in Pennisetum

    Directory of Open Access Journals (Sweden)

    Yamada-Akiyama Hitomi

    2011-10-01

    Full Text Available Abstract Background Apomixis is an intriguing trait in plants that results in maternal clones through seed reproduction. Apomixis is an elusive, but potentially revolutionary, trait for plant breeding and hybrid seed production. Recent studies arguing that apomicts are not evolutionary dead ends have generated further interest in the evolution of asexual flowering plants. Results In the present study, we investigate karyotypic variation in a single chromosome responsible for transmitting apomixis, the Apospory-Specific Genomic Region carrier chromosome, in relation to species phylogeny in the genera Pennisetum and Cenchrus. A 1 kb region from the 3' end of the ndhF gene and a 900 bp region from trnL-F were sequenced from 12 apomictic and eight sexual species in the genus Pennisetum and allied genus Cenchrus. An 800 bp region from the Apospory-Specific Genomic Region also was sequenced from the 12 apomicts. Molecular cytological analysis was conducted in sixteen Pennisetum and two Cenchrus species. Our results indicate that the Apospory-Specific Genomic Region is shared by all apomictic species while it is absent from all sexual species or cytotypes. Contrary to our previous observations in Pennisetum squamulatum and Cenchrus ciliaris, retrotransposon sequences of the Opie-2-like family were not closely associated with the Apospory-Specific Genomic Region in all apomictic species, suggesting that they may have been accumulated after the Apospory-Specific Genomic Region originated. Conclusions Given that phylogenetic analysis merged Cenchrus and newly investigated Pennisetum species into a single clade containing a terminal cluster of Cenchrus apomicts, the presumed monophyletic origin of Cenchrus is supported. The Apospory-Specific Genomic Region likely preceded speciation in Cenchrus and its lateral transfer through hybridization and subsequent chromosome repatterning may have contributed to further speciation in the two genera.

  10. Vaginal douching, condom use, and sexually transmitted infections among Chinese female sex workers.

    Science.gov (United States)

    Wang, Bo; Li, Xiaoming; Stanton, Bonita; Yang, Hongmei; Fang, Xiaoyi; Zhao, Ran; Dong, Baiqing; Zhou, Yuejiao; Liu, Wei; Liang, Shaoling

    2005-11-01

    Vaginal douching has been hypothesized to increase a woman's risk for human immunodeficiency virus (HIV) infection. However, data on the prevalence of this practice and its association with condom use and sexually transmitted infections (STIs) are limited. A cross-sectional survey among 454 female sex workers (FSWs) in a Chinese county. Vaginal douching was reported by 64.7% of the women. The prevalence of self-reported history of STI and that of current STI was 19.4% and 41.5%, respectively. Fifteen percent of the women reported consistent use of condoms with their clients and 8.4% with their regular partners. Vaginal douching was significantly associated with decreased use of condoms (with clients: OR = 0.31; with regular partner(s): OR = 0.22) and increased rate of self-reported STI history (OR = 1.95). However, there was no direct relation between douching and current STI. Over one third of the women believed that douching can prevent STI/HIV. Vaginal douching exposes FSWs to a high risk of STI/HIV. Medical professional and public health workers should correct women's misconception about the effectiveness of douching and discourage women from douching through educational activities.

  11. 40 CFR 1042.140 - Maximum engine power, displacement, power density, and maximum in-use engine speed.

    Science.gov (United States)

    2010-07-01

    ... cylinders having an internal diameter of 13.0 cm and a 15.5 cm stroke length, the rounded displacement would... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Maximum engine power, displacement... Maximum engine power, displacement, power density, and maximum in-use engine speed. This section describes...

  12. Determining Maximum Photovoltaic Penetration in a Distribution Grid considering Grid Operation Limits

    DEFF Research Database (Denmark)

    Kordheili, Reza Ahmadi; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    2014-01-01

    High penetration of photovoltaic panels in distribution grid can bring the grid to its operation limits. The main focus of the paper is to determine maximum photovoltaic penetration level in the grid. Three main criteria were investigated for determining maximum penetration level of PV panels...... for this grid: even distribution of PV panels, aggregation of panels at the beginning of each feeder, and aggregation of panels at the end of each feeder. Load modeling is done using Velander formula. Since PV generation is highest in the summer due to irradiation, a summer day was chosen to determine maximum......; maximum voltage deviation of customers, cables current limits, and transformer nominal value. Voltage deviation of different buses was investigated for different penetration levels. The proposed model was simulated on a Danish distribution grid. Three different PV location scenarios were investigated...

  13. Selection of the Maximum Spatial Cluster Size of the Spatial Scan Statistic by Using the Maximum Clustering Set-Proportion Statistic.

    Science.gov (United States)

    Ma, Yue; Yin, Fei; Zhang, Tao; Zhou, Xiaohua Andrew; Li, Xiaosong

    2016-01-01

    Spatial scan statistics are widely used in various fields. The performance of these statistics is influenced by parameters, such as maximum spatial cluster size, and can be improved by parameter selection using performance measures. Current performance measures are based on the presence of clusters and are thus inapplicable to data sets without known clusters. In this work, we propose a novel overall performance measure called maximum clustering set-proportion (MCS-P), which is based on the likelihood of the union of detected clusters and the applied dataset. MCS-P was compared with existing performance measures in a simulation study to select the maximum spatial cluster size. Results of other performance measures, such as sensitivity and misclassification, suggest that the spatial scan statistic achieves accurate results in most scenarios with the maximum spatial cluster sizes selected using MCS-P. Given that previously known clusters are not required in the proposed strategy, selection of the optimal maximum cluster size with MCS-P can improve the performance of the scan statistic in applications without identified clusters.

  14. The maximum entropy production and maximum Shannon information entropy in enzyme kinetics

    Science.gov (United States)

    Dobovišek, Andrej; Markovič, Rene; Brumen, Milan; Fajmut, Aleš

    2018-04-01

    We demonstrate that the maximum entropy production principle (MEPP) serves as a physical selection principle for the description of the most probable non-equilibrium steady states in simple enzymatic reactions. A theoretical approach is developed, which enables maximization of the density of entropy production with respect to the enzyme rate constants for the enzyme reaction in a steady state. Mass and Gibbs free energy conservations are considered as optimization constraints. In such a way computed optimal enzyme rate constants in a steady state yield also the most uniform probability distribution of the enzyme states. This accounts for the maximal Shannon information entropy. By means of the stability analysis it is also demonstrated that maximal density of entropy production in that enzyme reaction requires flexible enzyme structure, which enables rapid transitions between different enzyme states. These results are supported by an example, in which density of entropy production and Shannon information entropy are numerically maximized for the enzyme Glucose Isomerase.

  15. Solar Maximum Mission Experiment - Ultraviolet Spectroscopy and Polarimetry on the Solar Maximum Mission

    Science.gov (United States)

    Tandberg-Hanssen, E.; Cheng, C. C.; Woodgate, B. E.; Brandt, J. C.; Chapman, R. D.; Athay, R. G.; Beckers, J. M.; Bruner, E. C.; Gurman, J. B.; Hyder, C. L.

    1981-01-01

    The Ultraviolet Spectrometer and Polarimeter on the Solar Maximum Mission spacecraft is described. It is pointed out that the instrument, which operates in the wavelength range 1150-3600 A, has a spatial resolution of 2-3 arcsec and a spectral resolution of 0.02 A FWHM in second order. A Gregorian telescope, with a focal length of 1.8 m, feeds a 1 m Ebert-Fastie spectrometer. A polarimeter comprising rotating Mg F2 waveplates can be inserted behind the spectrometer entrance slit; it permits all four Stokes parameters to be determined. Among the observing modes are rasters, spectral scans, velocity measurements, and polarimetry. Examples of initial observations made since launch are presented.

  16. BER and optimal power allocation for amplify-and-forward relaying using pilot-aided maximum likelihood estimation

    KAUST Repository

    Wang, Kezhi

    2014-10-01

    Bit error rate (BER) and outage probability for amplify-and-forward (AF) relaying systems with two different channel estimation methods, disintegrated channel estimation and cascaded channel estimation, using pilot-aided maximum likelihood method in slowly fading Rayleigh channels are derived. Based on the BERs, the optimal values of pilot power under the total transmitting power constraints at the source and the optimal values of pilot power under the total transmitting power constraints at the relay are obtained, separately. Moreover, the optimal power allocation between the pilot power at the source, the pilot power at the relay, the data power at the source and the data power at the relay are obtained when their total transmitting power is fixed. Numerical results show that the derived BER expressions match with the simulation results. They also show that the proposed systems with optimal power allocation outperform the conventional systems without power allocation under the same other conditions. In some cases, the gain could be as large as several dB\\'s in effective signal-to-noise ratio.

  17. BER and optimal power allocation for amplify-and-forward relaying using pilot-aided maximum likelihood estimation

    KAUST Repository

    Wang, Kezhi; Chen, Yunfei; Alouini, Mohamed-Slim; Xu, Feng

    2014-01-01

    Bit error rate (BER) and outage probability for amplify-and-forward (AF) relaying systems with two different channel estimation methods, disintegrated channel estimation and cascaded channel estimation, using pilot-aided maximum likelihood method in slowly fading Rayleigh channels are derived. Based on the BERs, the optimal values of pilot power under the total transmitting power constraints at the source and the optimal values of pilot power under the total transmitting power constraints at the relay are obtained, separately. Moreover, the optimal power allocation between the pilot power at the source, the pilot power at the relay, the data power at the source and the data power at the relay are obtained when their total transmitting power is fixed. Numerical results show that the derived BER expressions match with the simulation results. They also show that the proposed systems with optimal power allocation outperform the conventional systems without power allocation under the same other conditions. In some cases, the gain could be as large as several dB's in effective signal-to-noise ratio.

  18. A New Resource for STD Clinical Providers: The Sexually Transmitted Diseases Clinical Consultation Network.

    Science.gov (United States)

    Caragol, Laura A; Wendel, Karen A; Anderson, Teri S; Burnside, Helen C; Finkenbinder, Allison; Fitch, John D; Kelley, Destiny H; Stewart, Terry W; Thrun, Mark; Rietmeijer, Cornelis A

    2017-08-01

    An online consultation tool, the Sexually Transmitted Diseases Clinical Consultation Network is a new resource for sexually transmitted disease clinicians and clinic managers. An initial evaluation shows that most requests (29%) were from medical doctors, followed by nurse practitioners (22%). Syphilis queries comprised 39% of consults followed by gonorrhea (12%) and chlamydia (11%).

  19. 47 CFR 25.220 - Non-conforming transmit/receive earth station operations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Non-conforming transmit/receive earth station operations. 25.220 Section 25.220 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Standards § 25.220 Non-conforming transmit/receive...

  20. 48 CFR 245.7206 - Transmitting DD Form 1342, DoD Property Record.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Transmitting DD Form 1342... Instructions 245.7206 Transmitting DD Form 1342, DoD Property Record. As a minimum, the plant clearance officer will provide the following information in a letter forwarding DD Forms 1342 to DSCR— (a) Number of DD...

  1. 76 FR 75523 - Vessel Monitoring Systems; Approved Mobile Transmitting Units and Communications Service...

    Science.gov (United States)

    2011-12-02

    ... Monitoring Systems; Approved Mobile Transmitting Units and Communications Service Providers for Use in... relevant features of the enhanced mobile transmitting unit (E-MTU) VMS and communications service providers... with the Orbcomm mobile communications provider service. Skymate can be reached at 866-SKYMATE and...

  2. 75 FR 63445 - Vessel Monitoring Systems; Approved Mobile Transmitting Units and Communications Service...

    Science.gov (United States)

    2010-10-15

    ... Monitoring Systems; Approved Mobile Transmitting Units and Communications Service Providers for Use in the... features of the VMS. ADDRESSES: To obtain copies of the list of NOAA-approved VMS mobile transmitting units and NOAA-approved VMS communications service providers, please contact the VMS Support Center at...

  3. A final size relation for epidemic models of vector-transmitted diseases

    OpenAIRE

    Fred Brauer

    2017-01-01

    We formulate and analyze an age of infection model for epidemics of diseases transmitted by a vector, including the possibility of direct transmission as well. We show how to determine a basic reproduction number. While there is no explicit final size relation as for diseases transmitted directly, we are able to obtain estimates for the final size of the epidemic.

  4. Neutral currents

    International Nuclear Information System (INIS)

    Paschos, E.A.

    1977-01-01

    It is stated that over the past few years considerable progress has been made in the field of weak interactions. The existence of neutral currents involving leptons and hadrons has been established and some of the questions concerning their detailed structure have been answered. This imposes constraints on the gauge theories and has eliminated large classes of models. New questions have also been raised, one of which concerns the conservation laws obeyed by neutral currents. The wide range of investigations is impressive and is expected to continue with new results from particle, nuclear, and atomic physics. Headings include - various aspects of a gauge theory (choice of group, the symmetry breaking scheme, representation assignments for fermion fields); space-time structure; isospin structure; leptonic neutral currents; and atomic experiments. (U.K.)

  5. Development of an Intelligent Maximum Power Point Tracker Using an Advanced PV System Test Platform

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Amoiridis, Anastasios; Beres, Remus Narcis

    2013-01-01

    The performance of photovoltaic systems is often reduced by the presence of partial shadows. The system efficiency and availability can be improved by a maximum power point tracking algorithm that is able to detect partial shadow conditions and to optimize the power output. This work proposes...... an intelligent maximum power point tracking method that monitors the maximum power point voltage and triggers a current-voltage sweep only when a partial shadow is detected, therefore minimizing power loss due to repeated current-voltage sweeps. The proposed system is validated on an advanced, flexible...... photovoltaic inverter system test platform that is able to reproduce realistic partial shadow conditions, both in simulation and on hardware test system....

  6. Neutral currents

    International Nuclear Information System (INIS)

    Aubert, B.

    1994-11-01

    The evidence for the existence of weak neutral current has been a very controverted topics in the early 1970's, as well as the muon did in the 1930's. The history is very rich considering the evolution of the experimental techniques in high energy particle physics. The history of the discovery and the study of weak neutral current is reviewed. Later the quest of the intermediate vector boson continues with the decision of the community to build a large proton antiproton collider. (K.A.). 14 refs., 1 fig

  7. Pattern of sexually transmitted infections in a tertiary care centre at Puducherry

    Directory of Open Access Journals (Sweden)

    Devi S

    2009-01-01

    Full Text Available Background: The prevalence of sexually transmitted infections (STI varies widely from region to region in our country. Aims: To highlight the pattern of STIs and the profile of patients with HIV infection in STD patients as seen at our hospital. Methods: A retrospective chart analysis of clients attending STI clinic, JIPMER, Puducherry, from June 2004 to June 2006 was done. Results: A total of 866 clients attended our STI clinic, out of whom 435 (50.2% had proven STI. STIs were more common in men, with a male (290: female (145 ratio of 2:1. Their age ranged from 1 year to 75 years (mean age = 32.38 years with the maximum number of patients in the age group of 21-30 years, while children constituted only 2.8%. Herpes genitalis (107 patients, 32.8% was the most common ulcerative STI, while genital wart was the most common nonulcerative STI (56 patients, 17.1%. Non-gonococcal urethritis (46 patients, 14.1% was more common than gonococcal urethritis. HIV infection was the most common STI in our study, at an alarmingly high rate of 34.5% (151/435. HIV seropositivity was more common in patients who presented with ulcerative STIs than with nonulcerative STIs. Conclusions: Herpes genitalis was the most common ulcerative STD, while genital wart was the most common nonulcerative STI in our study. The prevalence of HIV among STI clients in India has been on the rise, but has quite alarmingly become the most common STI in our study.

  8. Secret-Sharing over Multiple-Antenna Channels with Transmit Correlation

    KAUST Repository

    Zorgui, Marwen

    2015-01-07

    We consider secret-key agreement with public discussion over Rayleigh fastfading channels with transmit correlation. The legitimate receiver and the eavesdropper are assumed to have perfect channel knowledge while the transmitter has only knowledge of the transmit correlation matrix. First, We derive the expression of the key capacity under the considered setup. Then, we show that the optimal transmit strategy achieving the key capacity consists in transmitting Gaussian signals along the eingenvectors of the channel covariance matrix. The powers allocated to each channel mode are determined as the solution of a numerical optimization problem that we derive. We also provide a waterfilling interpretation of the optimal power allocation. Finally, we develop a necessary and sufficient condition for beamforming to be optimal, i.e., transmitting along the strongest channel mode only is key capacity-achieving.

  9. Secret-Sharing over Multiple-Antenna Channels with Transmit Correlation

    KAUST Repository

    Zorgui, Marwen; Rezki, Zouheir; Alomair, Basel; Alouini, Mohamed-Slim

    2015-01-01

    We consider secret-key agreement with public discussion over Rayleigh fastfading channels with transmit correlation. The legitimate receiver and the eavesdropper are assumed to have perfect channel knowledge while the transmitter has only knowledge of the transmit correlation matrix. First, We derive the expression of the key capacity under the considered setup. Then, we show that the optimal transmit strategy achieving the key capacity consists in transmitting Gaussian signals along the eingenvectors of the channel covariance matrix. The powers allocated to each channel mode are determined as the solution of a numerical optimization problem that we derive. We also provide a waterfilling interpretation of the optimal power allocation. Finally, we develop a necessary and sufficient condition for beamforming to be optimal, i.e., transmitting along the strongest channel mode only is key capacity-achieving.

  10. Interlaboratory comparison of dicentric chromosome assay using electronically transmitted images

    International Nuclear Information System (INIS)

    Garcia, O.; Di Giorgio, M.; Vallerga, M. B.; Radl, A.; Taja, M. R.; Seoane, A.; De Luca, J.; Stuck Oliveira, M.; Valdivia, P.; Lamadrid, A. I.; Gonzalez, J. E.; Romero, I.; Mandina, T.; Pantelias, G.; Terzoudi, G.; Guerrero-Carbajal, C.; Arceo Maldonado, C.; Espinoza, M.; Oliveros, N.; Martinez-Lopez, W.; Di Tomaso, M. V.; Mendez-Acuna, L.; Puig, R.; Roy, L.; Barquinero, J. F.

    2013-01-01

    The bottleneck in data acquisition during biological dosimetry based on a dicentric assay is the need to score dicentrics in a large number of lymphocytes. One way to increase the capacity of a given laboratory is to use the ability of skilled operators from other laboratories. This can be done using image analysis systems and distributing images all around the world. Two exercises were conducted to test the efficiency of such an approach involving 10 laboratories. During the first exercise (E1), the participant laboratories analysed the same images derived from cells exposed to 0.5 and 3 Gy; 100 images were sent to all participants for both doses. Whatever the dose, only about half of the cells were complete with well-spread metaphases suitable for analysis. A coefficient of variation (CV) on the standard deviation of 15 % was obtained for both doses. The trueness was better for 3 Gy (0.6 %) than for 0.5 Gy (37.8 %). The number of estimated doses classified as satisfactory according to the z-score was 3 at 0.5 Gy and 8 at 3 Gy for 10 dose estimations. In the second exercise, an emergency situation was tested, each laboratory was required to score a different set of 50 images in 2 d extracted from 500 downloaded images derived from cells exposed to 0.5 Gy. Then the remaining 450 images had to be scored within a week. Using 50 different images, the CV on the estimated doses (79.2 %) was not as good as in E1, probably associated to a lower number of cells analysed (50 vs. 100) or from the fact that laboratories analysed a different set of images. The trueness for the dose was better after scoring 500 cells (22.5 %) than after 50 cells (26.8 %). For the 10 dose estimations, the number of doses classified as satisfactory according to the z-score was 9, for both 50 and 500 cells. Overall, the results obtained support the feasibility of networking using electronically transmitted images. However, before its implementation some issues should be elucidated, such as the

  11. Screening for sexually transmitted diseases in rural South African women.

    Science.gov (United States)

    Schneider, H; Coetzee, D J; Fehler, H G; Bellingan, A; Dangor, Y; Radebe, F; Ballard, R C

    1998-06-01

    This paper reports on a study undertaken in a rural area of South Africa, to develop a non-laboratory tool to screen for sexually transmitted diseases (STDs) among family planning clients. A cross sectional study was performed of 249 consecutive women attending a family planning service between November and December 1994. A questionnaire was administered, and a clinical examination and laboratory tests conducted. Sociodemographic, clinical, and other non-laboratory variables that were significantly associated with laboratory evidence of infection were combined to produce non-hierarchical scoring systems for three "syndromes": gonococcal and/or chlamydial cervical infection, trichomoniasis, and cervical infection and/or trichomoniasis combined. The sensitivity, specificity, and predictive values of the scoring systems as a screening tool were assessed against the gold standard of laboratory tests. The prevalence of reproductive tract infections among the study participants was as follows: Chlamydia trachomatis 12%, Neisseria gonorrhoeae 3%, Trichomonas vaginalis 18%, and bacterial vaginosis 29%. Although vaginal discharge and other symptoms were frequently reported, symptoms bore no relation to the presence of infection. The following independent associations with gonococcal/chlamydial cervical infection were found: age less than 25 years and cervical mucopus and/or friability. Abnormal discharge on examination, visible inflammatory changes of the cervix (increased redness), no recent travel, and unemployment were associated with trichomoniasis. The combination of trichomonas and/or cervical infection ("STD syndrome") was associated with cervical mucopus/friability, unemployment, lack of financial support, and increased redness of the cervix. Of the three scoring systems developed on the basis of these associations, that of the "STD syndrome" achieved the best performance characteristics as a screening tool, with a sensitivity of 62%, specificity of 74%, and

  12. [Vector transmitted diseases and climate changes in Europe].

    Science.gov (United States)

    Rossati, Antonella; Bargiacchi, Olivia; Kroumova, Vesselina; Garavelli, Pietro Luigi

    2014-09-01

    The increase in temperatures recorded since the mid-nineteenth century is unprecedented in the history of mankind. The consequences of climate changes are numerous and can affect human health through direct (extreme events, natural disasters) or indirect (alteration of the ecosystem) mechanisms. Climate changes have repercussions on ecosystems, agriculture, social conditions, migration, conflicts and the transmission mode of infectious diseases. Vector-borne diseases are infections transmitted by the bite of infected arthropods such as mosquitoes, ticks, triatomines, sand flies and flies. Epidemiological cornerstones of vector-borne diseases are: the ecology and behaviour of the host, the ecology and behaviour of the vector, and the population's degree of immunity. Mosquito vectors related to human diseases mainly belong to the genus Culex, Aedes and Mansonia. Climate changes in Europe have increased the spread of new vectors, such as Aedes albopictus, and in some situations have made it possible to sustain the autochthonous transmission of some diseases (outbreak of Chukungunya virus in northern Italy in 2007, cases of dengue in the South of France and in Croatia). Despite the eradication of malaria from Europe, anopheline carriers are still present, and they may allow the transmission of the disease if the climatic conditions favour the development of the vectors and their contacts with plasmodium carriers. The tick Ixodes ricinus is a vector whose expansion has been documented both in latitude and in altitude in relation to the temperature increase; at the same time the related main viral and bacterial infections have increased. In northern Italy and Germany, the appearance of Leishmaniasis has been associated to climatic conditions that favour the development of the vector Phlebotomus papatasi and the maturation of the parasite within the vector, although the increase of cases of visceral leishmaniasis is also related to host immune factors, particularly

  13. Knowledge of adolescents regarding sexually transmitted infections and pregnancy.

    Science.gov (United States)

    Almeida, Rebeca Aranha Arrais Santos; Corrêa, Rita da Graça Carvalhal Frazão; Rolim, Isaura Letícia Tavares Palmeira; Hora, Jessica Marques da; Linard, Andrea Gomes; Coutinho, Nair Portela Silva; Oliveira, Priscila da Silva

    2017-01-01

    To investigate the knowledge of adolescents related to sexually transmitted infections (STIs), AIDS, and pregnancy, and understand the role of school in sex education. A qualitative descriptive study, developed through a semi-structured interview and a form for participant characterization, with 22 high school students from a public school aged 16 to 19 years. Data were submitted to content analysis. After analysis, four thematic categories were developed: sexuality and sex education; understanding of risk behaviors; knowledge of STI/AIDS; and knowledge of and practices for prevention. This study showed the need for preventive educational actions for adolescents, because the lack of information contributes to their vulnerability. The adolescents recognize the importance of sex education; therefore it is important to implement strategies to promote and protect health in the school environment to encourage and strengthen self-care in health. investigar o conhecimento de adolescentes relacionado às Infecções Sexualmente Transmissíveis (IST), AIDS e gravidez, além de conhecer a compreensão sobre o papel da escola na educação sexual. estudo qualitativo, descritivo, desenvolvido por meio de entrevista semiestruturada e formulário para caracterização dos participantes, com 22 adolescentes entre 16 e 19 anos de idade, estudantes do Ensino Médio em uma escola pública. Os dados foram submetidos à análise de conteúdo. da análise emergiram quatro categorias temáticas: Sexualidade e educação sexual; Compreensão de comportamentos de risco; Conhecimento de IST/AIDS; Conhecimento e práticas de prevenção. revelou-se a necessidade de ações educativas de prevenção para os adolescentes, pois a falta de informações contribui para a sua vulnerabilidade. Os adolescentes reconhecem a importância da educação sexual; consequentemente, é importante a implementação de estratégias de promoção e de proteção à saúde no ambiente escolar para contribuir e

  14. Maximum power point tracking controller for PV systems using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Bahgat, A.B.G. [Cairo Univ. (Egypt). Faculty of Engineering; Helwa, N.H.; Ahmad, G.E.; El Shenawy, E.T. [National Research Center, Dokki, Cairo (Egypt). Solar Energy Dept.

    2005-07-01

    This paper presents a development and implementation of a PC-based maximum power point tracker (MPPT) for PV system using neural networks (NN). The system consists of a PV module via a MPPT supplying a dc motor that drives an air fan. The control algorithm is developed to use the artificial NN for detecting the optimal operating point under different operating conditions, then the control action gives the driving signals to the MPPT. A PC is used for data acquisition, running the control algorithm, data storage, as well as data display and analysis. The system has been implemented and tested under various operating conditions. The experimental results showed that the PV system with MPPT always tracks the peak power point of the PV module under various operating conditions. The MPPT transmits about 97% of the actual maximum power generated by the PV module. The MPPT not only increases the power from the PV module to the load, but also maintains longer operating periods for the PV system. The air velocity and the air mass flow rate of the mechanical load are increased considerably, due to the increase of the PV system power. It is also found that the increase in the output energy due to using the MPPT is about 45.2% for a clear sunny day. (Author)

  15. Current algebra

    International Nuclear Information System (INIS)

    Jacob, M.

    1967-01-01

    The first three chapters of these lecture notes are devoted to generalities concerning current algebra. The weak currents are defined, and their main properties given (V-A hypothesis, conserved vector current, selection rules, partially conserved axial current,...). The SU (3) x SU (3) algebra of Gell-Mann is introduced, and the general properties of the non-leptonic weak Hamiltonian are discussed. Chapters 4 to 9 are devoted to some important applications of the algebra. First one proves the Adler- Weisberger formula, in two different ways, by either the infinite momentum frame, or the near-by singularities method. In the others chapters, the latter method is the only one used. The following topics are successively dealt with: semi leptonic decays of K mesons and hyperons, Kroll- Ruderman theorem, non leptonic decays of K mesons and hyperons ( ΔI = 1/2 rule), low energy theorems concerning processes with emission (or absorption) of a pion or a photon, super-convergence sum rules, and finally, neutrino reactions. (author) [fr

  16. Current Titles

    Energy Technology Data Exchange (ETDEWEB)

    Various

    2006-06-01

    This booklet is published for those interested in current research being conducted at the National Center for Electron Microscopy. The NCEM is a DOE-designated national user facility and is available at no charge to qualified researchers. Access is controlled by an external steering committee. Interested researchers may contact Jane Cavlina, Administrator, at 510/486-6036.

  17. Current scenario

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Current scenario. India , like other parts of the world, is also facing the problem of increase in the incidence of drug resistance in tuberculosis. Multi-drug resistance (MDR, resistance to RIF & INH) and extensively drug resistant strains (X-DR, resistance to RIF, INH, FQs ...

  18. Evaluation of performance and maximum length of continuous decks in bridges : part 1.

    Science.gov (United States)

    2011-06-01

    The purpose of this research was to evaluate the performance history of continuous bridge decks in the State of Georgia, to determine why the current design detail works, to recommend a new design detail, and to recommend the maximum and/or optimum l...

  19. Flow Control in Wells Turbines for Harnessing Maximum Wave Power

    Science.gov (United States)

    Garrido, Aitor J.; Garrido, Izaskun; Otaola, Erlantz; Maseda, Javier

    2018-01-01

    Oceans, and particularly waves, offer a huge potential for energy harnessing all over the world. Nevertheless, the performance of current energy converters does not yet allow us to use the wave energy efficiently. However, new control techniques can improve the efficiency of energy converters. In this sense, the plant sensors play a key role within the control scheme, as necessary tools for parameter measuring and monitoring that are then used as control input variables to the feedback loop. Therefore, the aim of this work is to manage the rotational speed control loop in order to optimize the output power. With the help of outward looking sensors, a Maximum Power Point Tracking (MPPT) technique is employed to maximize the system efficiency. Then, the control decisions are based on the pressure drop measured by pressure sensors located along the turbine. A complete wave-to-wire model is developed so as to validate the performance of the proposed control method. For this purpose, a novel sensor-based flow controller is implemented based on the different measured signals. Thus, the performance of the proposed controller has been analyzed and compared with a case of uncontrolled plant. The simulations demonstrate that the flow control-based MPPT strategy is able to increase the output power, and they confirm both the viability and goodness. PMID:29439408

  20. Maximum likelihood sequence estimation for optical complex direct modulation.

    Science.gov (United States)

    Che, Di; Yuan, Feng; Shieh, William

    2017-04-17

    Semiconductor lasers are versatile optical transmitters in nature. Through the direct modulation (DM), the intensity modulation is realized by the linear mapping between the injection current and the light power, while various angle modulations are enabled by the frequency chirp. Limited by the direct detection, DM lasers used to be exploited only as 1-D (intensity or angle) transmitters by suppressing or simply ignoring the other modulation. Nevertheless, through the digital coherent detection, simultaneous intensity and angle modulations (namely, 2-D complex DM, CDM) can be realized by a single laser diode. The crucial technique of CDM is the joint demodulation of intensity and differential phase with the maximum likelihood sequence estimation (MLSE), supported by a closed-form discrete signal approximation of frequency chirp to characterize the MLSE transition probability. This paper proposes a statistical method for the transition probability to significantly enhance the accuracy of the chirp model. Using the statistical estimation, we demonstrate the first single-channel 100-Gb/s PAM-4 transmission over 1600-km fiber with only 10G-class DM lasers.