NASA Astrophysics Data System (ADS)
Vakoch, Douglas A.
2011-02-01
With recently growing interest in the Active Search for Extraterrestrial Intelligence (SETI), in which humankind would send intentional signals to extraterrestrial civilizations, there have been increased concerns about appropriate policy, as well as the role of space law and ethics in guiding such activities. Implicit in these discussions are notions of responsibility and capability that affect judgments about whether humans or other civilizations should initiate transmissions. Existing protocols that guide SETI research address transmissions from Earth, but there is debate over whether these guidelines should inform de novo transmissions as well. Relevant responsibilities to address include (1) looking out for the interests of humankind as a whole, (2) being truthful in interstellar messages, and (3) benefiting extraterrestrial civilizations. Our capabilities as a species and a civilization affect how well we can fulfill responsibilities, as seen when we consider whether we will be able to reach consensus about message contents (and whether that would be desirable), and whether we have the capacity to decode messages from beings that rely on different sensory modalities. The interplay of these responsibilities and capabilities suggests that humankind should place increased emphasis on Active SETI.
Assessing the effects of underground mining activities on high-voltage overhead power lines
NASA Astrophysics Data System (ADS)
Gusev, Vladimir; Zhuravlyov, Alexei; Maliukhina, Elena
2017-11-01
This paper introduces a technique for predictive assessment of changes in the position of power transmission towers and condition of overhead power lines, located in the zone of influence of displacements and deformations of the Earth's surface caused by mining activities. A special approach for monitoring the technical condition of towers and cables is proposed. It is intended to address the issue of controlling the condition of transmission lines that are under the influence of underground mining activities and to checkmate such impact.
NASA Astrophysics Data System (ADS)
Li, Yutong; Hansen, Andreas; Karl Hedrick, J.; Zhang, Junzhi
2017-12-01
Active control of electric powertrains is challenging, due to the fact that backlash and structural flexibility in transmission components can cause severe performance degradation or even instability of the control system. Furthermore, high impact forces in transmissions reduce driving comfort and possibly lead to damage of the mechanical elements in contact. In this paper, a nonlinear electric powertrain is modelled as a piecewise affine (PWA) system. The novel receding horizon sliding control (RHSC) idea is extended to constrained PWA systems and utilised to systematically address the active control problem for electric powertrains. Simulations are conducted in Matlab/Simulink in conjunction with the high fidelity Carsim software. RHSC shows superior jerk suppression and target wheel speed tracking performance as well as reduced computational cost over classical model predictive control (MPC). This indicates the newly proposed RHSC is an effective method to address the active control problem for electric powertrains.
Molecular Machine-Based Active Plasmonics
2011-07-21
C. S. Lin, M. Lu, T. Gao, T.J. Huang), J. Appl. Phys. 2010, 108, 043514. 33. Ordered Au nanodisk and nanohole arrays: fabrication and applications...Stoddart), J. Am. Chem. Soc. 2011, 133, 4538–4547. 41. Frequency-addressed tunable transmission in optically thin metallic nanohole arrays with
77 FR 74181 - Notice of Commission Staff Attendance
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-13
... Commission's staff may attend the following meeting related to the transmission planning activities of ISO... information, see: http://www.iso-ne.com/committees/comm_wkgrps/index.html The discussions at the meeting described above may address matters at issue in the following proceedings: Docket No. ER13-193-000, ISO New...
Hueston, W; Travis, D; van Klink, E
2011-04-01
The effectiveness of risk mitigation may be compromised by informal trade, including illegal activities, parallel markets and extra-legal activities. While no regulatory system is 100% effective in eliminating the risk of disease transmission through animal and animal product trade, extreme risk aversion in formal import health regulations may increase informal trade, with the unintended consequence of creating additional risks outside regulatory purview. Optimal risk mitigation on a national scale requires scientifically sound yet flexible mitigation strategies that can address the competing risks of formal and informal trade. More robust risk analysis and creative engagement of nontraditional partners provide avenues for addressing informal trade.
Complete solid state lighting (SSL) line at CEA LETI
NASA Astrophysics Data System (ADS)
Robin, I. C.; Ferret, P.; Dussaigne, A.; Bougerol, C.; Salomon, D.; Chen, X. J.; Charles, M.; Tchoulfian, P.; Gasse, A.; Lagrange, A.; Consonni, M.; Bono, H.; Levy, F.; Desieres, Y.; Aitmani, A.; Makram-Matta, S.; Bialic, E.; Gorrochategui, P.; Mendizabal, L.
2014-09-01
With a long experience in optoelectronics, CEA-LETI has focused on Light Emitting Diode (LED) lighting since 2006. Today, all the technical challenges in the implementation of GaN LED based solid state lighting (SSL) are addressed at CEA-LETI who is now an RandD player throughout the entire value chain of LED lighting. The SSL Line at CEA-LETI first deals with the simulation of the active structures and LED devices. Then the growth is addressed in particular 2D growth on 200 mm silicon substrates. Then, technological steps are developed for the fabrication of LED dies with innovative architectures. For instance, Versatile LED Array Devices are currently being developed with a dedicated μLED technology. The objective in this case is to achieve monolithical LED arrays reported and interconnected through a silicon submount. In addition to the required bonding and 3D integration technologies, new solutions for LED chip packaging, thermal management of LED lamps and luminaires are also addressed. LETI is also active in Smart Lighting concepts which offer the possibility of new application fields for SSL technologies. An example is the recent development at CEA LETI of Visible Light Communication Technology also called LiFi. With this technology, we demonstrated a transmission rate up to 10 Mb/s and real time HD-Video transmission.
Immunotherapies to prevent mother-to-child transmission of HIV.
Hicar, Mark D
2013-03-01
Although pharmacological interventions have been successful in reducing prevention of maternal to child transmission (PMTCT) of HIV, there is concern that complete elimination through this mode of transmission will require other measures. Immunotherapies in infants or pregnant mothers may be able to eradicate this form of transmission. A recent vaccine trial in adults showed encouraging results, but as in most HIV safety and efficacy vaccine trials, the question of MTCT was not addressed. Concentrating transmission studies and vaccine studies in the setting of MTCT offers several advantages. MTCT has a generally reproducible known transmission rate and has been successfully used to assess pharmacological interventions on decreasing transmission. Even in resource poor settings, the infrastructure for neonatal vaccination is already in place. Although rare, both passive and active vaccination trials have been successfully completed in pediatric populations. Unfortunately, little success in affecting MTCT has been shown. Largely, a correlate of protection in any type of transmission, including MTCT, is unknown. Data supports a role for antibodies in effecting strain and transmission during MTCT. The role of antibodies in MTCT is reviewed with a focus on recent passive immunization and considerations for future studies.
ERIC Educational Resources Information Center
Sagrestano, Lynda M.; Paikoff, Roberta L.
Adolescent sexual activity and the resulting pregnancy and transmission of sexually transmitted diseases have been on the rise during the past several decades. This chapter addresses each of the three objectives regarding sexual behavior outlined in the Healthy People 2000 initiative. Background data and trends in adolescent sexual behavior are…
41 CFR 102-192.140 - What are your general responsibilities as a Federal mail center manager?
Code of Federal Regulations, 2013 CFR
2013-07-01
... transmission of data in lieu of mail, reducing the number of handwritten addresses on outgoing mail, and other... processing activities at the facility, including all regularly scheduled, small package, and expedited... security office, the Postal Inspection Service, or other appropriate authority; (k) Track incoming packages...
Active control of sound transmission through partitions composed of discretely controlled modules
NASA Astrophysics Data System (ADS)
Leishman, Timothy W.
This thesis provides a detailed theoretical and experimental investigation of active segmented partitions (ASPs) for the control of sound transmission. ASPs are physically segmented arrays of interconnected acoustically and structurally small modules that are discretely controlled using electronic controllers. Theoretical analyses of the thesis first address physical principles fundamental to ASP modeling and experimental measurement techniques. Next, they explore specific module configurations, primarily using equivalent circuits. Measured normal-incidence transmission losses and related properties of experimental ASPs are determined using plane wave tubes and the two-microphone transfer function technique. A scanning laser vibrometer is also used to evaluate distributed transmitting surface vibrations. ASPs have the inherent potential to provide excellent active sound transmission control (ASTC) through lightweight structures, using very practical control strategies. The thesis analyzes several unique ASP configurations and evaluates their abilities to produce high transmission losses via global minimization of normal transmitting surface vibrations. A novel dual diaphragm configuration is shown to employ this strategy particularly well. It uses an important combination of acoustical actuation and mechano-acoustical segmentation to produce exceptionally high transmission loss (e.g., 50 to 80 dB) over a broad frequency range-including lower audible frequencies. Such performance is shown to be comparable to that produced by much more massive partitions composed of thick layers of steel or concrete and sand. The configuration uses only simple localized error sensors and actuators, permitting effective use of independent single-channel controllers in a decentralized format. This work counteracts the commonly accepted notion that active vibration control of partitions is an ineffective means of controlling sound transmission. With appropriate construction, actuation, and error sensing, ASPs can achieve high sound transmission loss through efficient global control of transmitting surface vibrations. This approach is applicable to a wide variety of source and receiving spaces-and to both near fields and far fields.
The risk of airborne influenza transmission in passenger cars.
Knibbs, L D; Morawska, L; Bell, S C
2012-03-01
Travel in passenger cars is a ubiquitous aspect of the daily activities of many people. During the 2009 influenza A(H1N1) pandemic a case of probable transmission during car travel was reported in Australia, to which spread via the airborne route may have contributed. However, there are no data to indicate the likely risks of such events, and how they may vary and be mitigated. To address this knowledge gap, we estimated the risk of airborne influenza transmission in two cars (1989 model and 2005 model) by employing ventilation measurements and a variation of the Wells-Riley model. Results suggested that infection risk can be reduced by not recirculating air; however, estimated risk ranged from 59% to 99·9% for a 90-min trip when air was recirculated in the newer vehicle. These results have implications for interrupting in-car transmission of other illnesses spread by the airborne route.
Cell-cell signaling controls Xylella fastidiosa interactions with both insects and plants
Newman, Karyn L.; Almeida, Rodrigo P. P.; Purcell, Alexander H.; Lindow, Steven E.
2004-01-01
Xylella fastidiosa, which causes Pierce's disease of grapevine and other important plant diseases, is a xylem-limited bacterium that depends on insect vectors for transmission. Although many studies have addressed disease symptom development and transmission of the pathogen by vectors, little is known about the bacterial mechanisms driving these processes. Recently available X. fastidiosa genomic sequences and molecular tools have provided new routes for investigation. Here, we show that a diffusible signal molecule is required for biofilm formation in the vector and for vector transmission to plants. We constructed strains of X. fastidiosa mutated in the rpfF gene and determined that they are unable to produce the signal activity. In addition, rpfF mutants are more virulent than the wild type when mechanically inoculated into plants. This signal therefore directs interaction of X. fastidiosa with both its insect vector and plant host. Interestingly, rpfF mutants can still form in planta biofilms, which differ architecturally from biofilms in insects, suggesting that biofilm architecture, rather than a passive response to the environment, is actively determined by X. fastidiosa gene expression. This article reports a cell-cell signaling requirement for vector transmission. Identification of the genes regulated by rpfF should elucidate bacterial factors involved in transmission and biofilm formation in the insect. PMID:14755059
The evolution of plant virus transmission pathways
Frédéric M. Hamelin; Linda J.S. Allen; Holly R. Prendeville; M. Reza Hajimorad; Michael J. Jeger
2016-01-01
The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, oravector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which...
Progress toward poliomyelitis eradication - Afghanistan and Pakistan, 2009.
2010-03-12
Afghanistan, Pakistan, India, and Nigeria are the four remaining countries where indigenous wild poliovirus (WPV) transmission has never been interrupted. This report updates previous reports and describes polio eradication activities in Afghanistan and Pakistan during January-December 2009 and proposed activities in 2010 to address challenges. During 2009, both countries continued to conduct coordinated supplemental immunization activities (SIAs) and used multiple strategies to reach previously unreached children. These strategies included 1) use of short interval additional dose (SIAD) SIAs to administer a dose of oral poliovirus vaccine (OPV) within 1-2 weeks after a prior dose during negotiated periods of security; 2) systematic engagement of local leaders; 3) negotiations with conflict parties; and 4) increased engagement of nongovernmental organizations delivering basic health services. However, security problems continued to limit access by vaccination teams to large numbers of children. In Afghanistan, poliovirus transmission during 2009 predominantly occurred in 12 high-risk districts in the conflict-affected South Region; 38 WPV cases were confirmed in 2009, compared with 31 in 2008. In Pakistan, 89 WPV cases were confirmed in 2009, compared with 118 in 2008, but transmission persisted both in security-compromised areas and in accessible areas, where managerial and operational problems continued to affect immunization coverage. Continued efforts to enhance safe access of vaccination teams in insecure areas will be required for further progress toward interruption of WPV transmission in Afghanistan and Pakistan. In addition, substantial improvements in subnational accountability and oversight are needed to improve immunization activities in Pakistan.
Ayala, Jennifer E.; Niswender, Colleen M.; Luo, Qingwei; Banko, Jessica L.; Conn, P. Jeffrey
2008-01-01
Summary Group III metabotropic glutamate receptors (mGluRs) reduce synaptic transmission at the Schaffer collateral-CA1 (SC-CA1) synapse in rats by a presynaptic mechanism. Previous studies show that low concentrations of the group III-selective agonist, L-AP4, reduce synaptic transmission in slices from neonatal but not adult rats, whereas high micromolar concentrations reduce transmission in both age groups. L-AP4 activates mGluRs 4 and 8 at much lower concentrations than those required to activate mGluR7, suggesting that the group III mGluR subtype modulating transmission is a high affinity receptor in neonates and a low affinity receptor in adults. The previous lack of subtype selective ligands has made it difficult to test this hypothesis. We have measured fEPSPs in the presence of novel subtype selective agents to address this question. We show that the effects of L-AP4 can be blocked by LY341495 in both neonates and adults, verifying that these effects are mediated by mGluRs. In addition, the selective mGluR8 agonist, DCPG, has a significant effect in slices from neonatal rats but does not reduce synaptic transmission in adult slices. The mGluR4 selective allosteric potentiator, PHCCC, is unable to potentiate the L-AP4-induced effects at either age. Taken together, our data suggest that group III mGluRs regulate transmission at the SC-CA1 synapse throughout development but there is a developmental regulation of the subtypes involved so that that both mGluR8 serves this role in neonates but not adults whereas mGluR7 is involved in regulating transmission at this synapse in throughout postnatal development. PMID:18255102
Model-Based Anomaly Detection for a Transparent Optical Transmission System
NASA Astrophysics Data System (ADS)
Bengtsson, Thomas; Salamon, Todd; Ho, Tin Kam; White, Christopher A.
In this chapter, we present an approach for anomaly detection at the physical layer of networks where detailed knowledge about the devices and their operations is available. The approach combines physics-based process models with observational data models to characterize the uncertainties and derive the alarm decision rules. We formulate and apply three different methods based on this approach for a well-defined problem in optical network monitoring that features many typical challenges for this methodology. Specifically, we address the problem of monitoring optically transparent transmission systems that use dynamically controlled Raman amplification systems. We use models of amplifier physics together with statistical estimation to derive alarm decision rules and use these rules to automatically discriminate between measurement errors, anomalous losses, and pump failures. Our approach has led to an efficient tool for systematically detecting anomalies in the system behavior of a deployed network, where pro-active measures to address such anomalies are key to preventing unnecessary disturbances to the system's continuous operation.
Prevention and treatment of HIV addicted patients: a biopsychosocial approach.
Iskandar, Shelly; van Crevel, Reinout; Siregar, I M P; Achmad, T H; van der Ven, A J A M; de Jong, C A J
2009-07-01
Injecting drug use is the main route of HIV transmission in many parts of Indonesia. Efforts to prevent HIV-transmission through injecting drug use mostly focus on subjects who actively inject. In scientific publications, the term 'injecting drug users' tends to be used without a clear definition and without specifying the pattern of drug use as current or former drug use, frequency, duration, type of injected drug(s) or context (e.g. imprisonment). Actually, injecting drug users (IDUs) have different drug use patterns, risk behavior, somatic co-morbidity, psychiatric co-morbidity, and psychosocial problems. In fact, these patients are suffering from addiction as a chronic brain disease in co-occurrence with somatic and psychiatric disorder and many social problems. Failing in addressing the problems comprehensively will lead to the failure of drug treatment. This is why addiction can be best studied and treated from a biopsychosocial perspective. Accordingly, treatment goals can be differentiated in crisis intervention, cure or recovery (detoxification, relapse prevention), and care or partial remission (stabilization and harm reduction). In summary, injecting drug use in Indonesia is not a single entity and patient oriented prevention and care for IDUs, especially focusing on their addiction, should be addressed to prevent the transmission of HIV/AIDS.
The effect of glycogen phosphorolysis on basal glutaminergic transmission.
Mozrzymas, Jerzy; Szczęsny, Tomasz; Rakus, Darek
2011-01-14
Astrocytic glycogen metabolism sustains neuronal activity but its impact on basal glutamatergic synaptic transmission is not clear. To address this issue, we have compared the effect of glycogen breakdown inhibition on miniature excitatory postsynaptic currents (mEPSCs) in rat hippocampal pure neuronal culture (PNC) and in astrocyte-neuronal co-cultures (ANCC). Amplitudes of mEPSC in ANCC were nearly twice as large as in PNC with no difference in current kinetics. Inhibition of glycogen phosphorylase reduced mEPSC amplitude by roughly 40% in ANCC being ineffective in PNC. Altogether, these data indicate that astrocyte-neuronal interaction enhances basal mEPSCs in ANCC mainly due to astrocytic glycogen metabolism. Copyright © 2010 Elsevier Inc. All rights reserved.
2011-06-01
5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Medical Research Detachment, Lima , Peru, 8. PERFORMING ORGANIZATION...outbreaks of giardiasis have been linked to un- filtered water from shallow wells, persistent contamination of communal drinking water sources, and...The key to the prevention of giardiasis transmission lies in preventing fecal contamination of food and water, and preventing direct transmission
Izumi, Kiyohiko; Ohkado, Akihiro; Uchimura, Kazuhiro; Murase, Yoshiro; Tatsumi, Yuriko; Kayebeta, Aya; Watanabe, Yu; Ishikawa, Nobukatsu
2015-01-01
Identifying ongoing tuberculosis infection sites is crucial for breaking chains of transmission in tuberculosis-prevalent urban areas. Previous studies have pointed out that detection of local accumulation of tuberculosis patients based on their residential addresses may be limited by a lack of matching between residences and tuberculosis infection sites. This study aimed to identify possible tuberculosis hotspots using TB genotype clustering statuses and a concept of "activity space", a place where patients spend most of their waking hours. We further compared the spatial distribution by different residential statuses and describe urban environmental features of the detected hotspots. Culture-positive tuberculosis patients notified to Shinjuku city from 2003 to 2011 were enrolled in this case-based cross-sectional study, and their demographic and clinical information, TB genotype clustering statuses, and activity space were collected. Spatial statistics (Global Moran's I and Getis-Ord Gi* statistics) identified significant hotspots in 152 census tracts, and urban environmental features and tuberculosis patients' characteristics in these hotspots were assessed. Of the enrolled 643 culture-positive tuberculosis patients, 416 (64.2%) were general inhabitants, 42 (6.5%) were foreign-born people, and 184 were homeless people (28.6%). The percentage of overall genotype clustering was 43.7%. Genotype-clustered general inhabitants and homeless people formed significant hotspots around a major railway station, whereas the non-clustered general inhabitants formed no hotspots. This suggested the detected hotspots of activity spaces may reflect ongoing tuberculosis transmission sites and were characterized by smaller residential floor size and a higher proportion of non-working households. Activity space-based spatial analysis suggested possible TB transmission sites around the major railway station and it can assist in further comprehension of TB transmission dynamics in an urban setting in Japan.
High Resolution Displays Using NCAP Liquid Crystals
NASA Astrophysics Data System (ADS)
Macknick, A. Brian; Jones, Phil; White, Larry
1989-07-01
Nematic curvilinear aligned phase (NCAP) liquid crystals have been found useful for high information content video displays. NCAP materials are liquid crystals which have been encapsulated in a polymer matrix and which have a light transmission which is variable with applied electric fields. Because NCAP materials do not require polarizers, their on-state transmission is substantially better than twisted nematic cells. All dimensional tolerances are locked in during the encapsulation process and hence there are no critical sealing or spacing issues. By controlling the polymer/liquid crystal morphology, switching speeds of NCAP materials have been significantly improved over twisted nematic systems. Recent work has combined active matrix addressing with NCAP materials. Active matrices, such as thin film transistors, have given displays of high resolution. The paper will discuss the advantages of NCAP materials specifically designed for operation at video rates on transistor arrays; applications for both backlit and projection displays will be discussed.
Prather, Cynthia; Marshall, Khiya; Courtenay-Quirk, Cari; Williams, Kim; Eke, Agatha; O'Leary, Ann; Stratford, Dale
2012-08-01
Microenterprise programs are widely used to improve health outcomes among women internationally. However, there is little information on applicability to American women living in poverty. We conducted formative research to identify activities that are viable and attractive, that may produce income to address some proportion of economic need and could be incorporated in the development of a micro-enterprise HIV-prevention intervention to reduce HIV/STD transmission among unemployed or underemployed African American women at risk for HIV. Focus groups were convened with young African American women and community leaders in two southern states. Interviews with women participating in the focus groups were also convened. Findings suggest an intervention should incorporate activities to increase self-esteem, enhance employability and job sustainability to decrease financial dependence. This research serves as the foundation for developing a novel approach to HIV prevention in the U.S. that may directly address poverty as a social determinant of health.
2017-01-01
This paper summarises key advances in defining the infectious reservoir for malaria and the measurement of transmission for research and programmatic use since the Malaria Eradication Research Agenda (malERA) publication in 2011. Rapid and effective progress towards elimination requires an improved understanding of the sources of transmission as well as those at risk of infection. Characterising the transmission reservoir in different settings will enable the most appropriate choice, delivery, and evaluation of interventions. Since 2011, progress has been made in a number of areas. The extent of submicroscopic and asymptomatic infections is better understood, as are the biological parameters governing transmission of sexual stage parasites. Limitations of existing transmission measures have been documented, and proof-of-concept has been established for new innovative serological and molecular methods to better characterise transmission. Finally, there now exists a concerted effort towards the use of ensemble datasets across the spectrum of metrics, from passive and active sources, to develop more accurate risk maps of transmission. These can be used to better target interventions and effectively monitor progress toward elimination. The success of interventions depends not only on the level of endemicity but also on how rapidly or recently an area has undergone changes in transmission. Improved understanding of the biology of mosquito–human and human–mosquito transmission is needed particularly in low-endemic settings, where heterogeneity of infection is pronounced and local vector ecology is variable. New and improved measures of transmission need to be operationally feasible for the malaria programmes. Outputs from these research priorities should allow the development of a set of approaches (applicable to both research and control programmes) that address the unique challenges of measuring and monitoring transmission in near-elimination settings and defining the absence of transmission. PMID:29190279
47 CFR 54.5 - Terms and definitions.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., or making available information via telecommunications, and includes electronic publishing, but does... transmission of information as common carriage; (2) The transmission of information as part of a gateway to an... information, but may include data transmission, address translation, protocol conversion, billing management...
47 CFR 54.5 - Terms and definitions.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., or making available information via telecommunications, and includes electronic publishing, but does... transmission of information as common carriage; and (2) The transmission of information as part of a gateway to... content of information, but may include data transmission, address translation, protocol conversion...
47 CFR 54.5 - Terms and definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., or making available information via telecommunications, and includes electronic publishing, but does... transmission of information as common carriage; (2) The transmission of information as part of a gateway to an... information, but may include data transmission, address translation, protocol conversion, billing management...
Vector-virus interactions and transmission dynamics of West Nile virus.
Ciota, Alexander T; Kramer, Laura D
2013-12-09
West Nile virus (WNV; Flavivirus; Flaviviridae) is the cause of the most widespread arthropod-borne viral disease in the world and the largest outbreak of neuroinvasive disease ever observed. Mosquito-borne outbreaks are influenced by intrinsic (e.g., vector and viral genetics, vector and host competence, vector life-history traits) and extrinsic (e.g., temperature, rainfall, human land use) factors that affect virus activity and mosquito biology in complex ways. The concept of vectorial capacity integrates these factors to address interactions of the virus with the arthropod host, leading to a clearer understanding of their complex interrelationships, how they affect transmission of vector-borne disease, and how they impact human health. Vertebrate factors including host competence, population dynamics, and immune status also affect transmission dynamics. The complexity of these interactions are further exacerbated by the fact that not only can divergent hosts differentially alter the virus, but the virus also can affect both vertebrate and invertebrate hosts in ways that significantly alter patterns of virus transmission. This chapter concentrates on selected components of the virus-vector-vertebrate interrelationship, focusing specifically on how interactions between vector, virus, and environment shape the patterns and intensity of WNV transmission.
Vector-Virus Interactions and Transmission Dynamics of West Nile Virus
Ciota, Alexander T.; Kramer, Laura D.
2013-01-01
West Nile virus (WNV; Flavivirus; Flaviviridae) is the cause of the most widespread arthropod-borne viral disease in the world and the largest outbreak of neuroinvasive disease ever observed. Mosquito-borne outbreaks are influenced by intrinsic (e.g., vector and viral genetics, vector and host competence, vector life-history traits) and extrinsic (e.g., temperature, rainfall, human land use) factors that affect virus activity and mosquito biology in complex ways. The concept of vectorial capacity integrates these factors to address interactions of the virus with the arthropod host, leading to a clearer understanding of their complex interrelationships, how they affect transmission of vector-borne disease, and how they impact human health. Vertebrate factors including host competence, population dynamics, and immune status also affect transmission dynamics. The complexity of these interactions are further exacerbated by the fact that not only can divergent hosts differentially alter the virus, but the virus also can affect both vertebrate and invertebrate hosts in ways that significantly alter patterns of virus transmission. This chapter concentrates on selected components of the virus-vector-vertebrate interrelationship, focusing specifically on how interactions between vector, virus, and environment shape the patterns and intensity of WNV transmission. PMID:24351794
NASA Astrophysics Data System (ADS)
Bulega, T.; Kyeyune, A.; Onek, P.; Sseguya, R.; Mbabazi, D.; Katwiremu, E.
2011-10-01
Several publications have identified technical challenges facing Uganda's National Transmission Backbone Infrastructure project. This research addresses the technical limitations of the National Transmission Backbone Infrastructure project, evaluates the goals of the project, and compares the results against the technical capability of the backbone. The findings of the study indicate a bandwidth deficit, which will be addressed by using dense wave division multiplexing repeaters, leasing bandwidth from private companies. Microwave links for redundancy, a Network Operation Center for operation and maintenance, and deployment of wireless interoperability for microwave access as a last-mile solution are also suggested.
Cubic-panorama image dataset analysis for storage and transmission
NASA Astrophysics Data System (ADS)
Salehi, Saeed; Dubois, Eric
2013-02-01
In this paper we address the problem of disparity estimation required for free navigation in acquired cubicpanorama image datasets. A client server based scheme is assumed and a remote user is assumed to seek information at each navigation step. The initial compression of such image datasets for storage as well as the transmission of the required data is addressed in this work. Regarding the compression of such data for storage, a fast method that uses properties of the epipolar geometry together with the cubic format of panoramas is used to estimate disparity vectors efficiently. Assuming the use of B pictures, the concept of forward and backward prediction is addressed. Regarding the transmission stage, a new disparity vector transcoding-like scheme is introduced and a frame conversion scenario is addressed. Details on how to pick the best vector among candidate disparity vectors is explained. In all the above mentioned cases, results are compared both visually through error images as well as using the objective measure of Peak Signal to Noise Ratio (PSNR) versus time.
Single transmission line interrogated multiple channel data acquisition system
Fasching, George E.; Keech, Jr., Thomas W.
1980-01-01
A single transmission line interrogated multiple channel data acquisition system is provided in which a plurality of remote station/sensor circuits each monitors a specific process variable and each transmits measurement values over a single transmission line to a master interrogating station when addressed by said master interrogating station. Typically, as many as 330 remote stations may be parallel connected to the transmission line which may exceed 7,000 feet. The interrogation rate is typically 330 stations/second. The master interrogating station samples each station according to a shared, charging transmit-receive cycle. All remote station address signals, all data signals from the remote stations/sensors and all power for all of the remote station/sensors are transmitted via a single continuous terminated coaxial cable. A means is provided for periodically and remotely calibrating all remote sensors for zero and span. A provision is available to remotely disconnect any selected sensor station from the main transmission line.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-08
... DEPARTMENT OF AGRICULTURE Forest Service Final Tropic to Hatch 138 kV Transmission Line Project..., has prepared a Final Environmental Impact Statement (FEIS) for the Tropic to Hatch 138 kV Transmission.... ADDRESSES: Copies of the Tropic to Hatch 138 kV Transmission Line Project FEIS/PMPA for the Grand Staircase...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-05
..., RM13-14-000 and RM13-15-000] Monitoring System Conditions--Transmission Operations Reliability...) 502-6817, [email protected] . Robert T. Stroh (Legal Information), Office of the General... Reliability Standards ``address the important reliability goal of ensuring that the transmission system is...
Active control of counter-rotating open rotor interior noise in a Dornier 728 experimental aircraft
NASA Astrophysics Data System (ADS)
Haase, Thomas; Unruh, Oliver; Algermissen, Stephan; Pohl, Martin
2016-08-01
The fuel consumption of future civil aircraft needs to be reduced because of the CO2 restrictions declared by the European Union. A consequent lightweight design and a new engine concept called counter-rotating open rotor are seen as key technologies in the attempt to reach this ambitious goals. Bearing in mind that counter-rotating open rotor engines emit very high sound pressures at low frequencies and that lightweight structures have a poor transmission loss in the lower frequency range, these key technologies raise new questions in regard to acoustic passenger comfort. One of the promising solutions for the reduction of sound pressure levels inside the aircraft cabin are active sound and vibration systems. So far, active concepts have rarely been investigated for a counter-rotating open rotor pressure excitation on complex airframe structures. Hence, the state of the art is augmented by the preliminary study presented in this paper. The study shows how an active vibration control system can influence the sound transmission of counter-rotating open rotor noise through a complex airframe structure into the cabin. Furthermore, open questions on the way towards the realisation of an active control system are addressed. In this phase, an active feedforward control system is investigated in a fully equipped Dornier 728 experimental prototype aircraft. In particular, the sound transmission through the airframe, the coupling of classical actuators (inertial and piezoelectric patch actuators) into the structure and the performance of the active vibration control system with different error sensors are investigated. It can be shown that the active control system achieves a reduction up to 5 dB at several counter-rotating open rotor frequencies but also that a better performance could be achieved through further optimisations.
Vertical Integration, Monopoly, and the First Amendment.
ERIC Educational Resources Information Center
Brennan, Timothy J.
This paper addresses the relationship between the First Amendment, monopoly of transmission media, and vertical integration of transmission and content provision. A survey of some of the incentives a profit-maximizing transmission monopolist may have with respect to content is followed by a discussion of how vertical integration affects those…
Teacher Education beyond Transmission: Challenges and Opportunities for Iranian Teachers of English
ERIC Educational Resources Information Center
Safari, Parvin; Rashidi, Nasser
2015-01-01
The teacher education field has recently undergone dramatic changes leading to a shift of focus from transmission models towards alternative approaches and theories that emerged in the post-transmission era addressing sociocultural, political, ideological, and critical issues. Despite worldwide changes in teacher education programs, it seems that…
Quan, Tran Minh; Phuong, Huynh Thi; Vy, Nguyen Ha Thao; Thanh, Nguyen Thi Le; Lien, Nguyen Thi Nam; Hong, Tran Thi Kim; Dung, Pham Ngoc; Chau, Nguyen Van Vinh; Boni, Maciej F; Clapham, Hannah E
2018-02-01
Arbovirus infections are a serious concern in tropical countries due to their high levels of transmission and morbidity. With the outbreaks of chikungunya (CHIKV) in surrounding regions in recent years and the fact that the environment in Vietnam is suitable for the vectors of CHIKV, the possibility of transmission of CHIKV in Vietnam is of great interest. However, information about CHIKV activity in Vietnam remains limited. In order to address this question, we performed a systematic review of CHIKV in Vietnam and a CHIKV seroprevalence survey. The seroprevalence survey tested for CHIKV IgG in population serum samples from individuals of all ages in 2015 from four locations in Vietnam. The four locations were An Giang province (n = 137), Ho Chi Minh City (n = 136), Dak Lak province (n = 137), and Hue City (n = 136). The findings give us evidence of some CHIKV activity: 73/546 of overall samples were seropositive (13.4%). The age-adjusted seroprevalences were 12.30% (6.58-18.02), 13.42% (7.16-19.68), 7.97% (3.56-12.38), and 3.72% (1.75-5.69) in An Giang province, Ho Chi Minh City, Dak Lak province, and Hue City respectively. However, the age-stratified seroprevalence suggests that the last transmission ended around 30 years ago, consistent with results from the systematic review. We see no evidence for on-going transmission in three of the locations, though with some evidence of recent exposure in Dak Lak, most likely due to transmission in neighbouring countries. Before the 1980s, when transmission was occurring, we estimate on average 2-4% of the population were infected each year in HCMC and An Giang and Hue (though transmision ended earlier in Hue). We estimate lower transmission in Dak Lak, with around 1% of the population infected each year. In conclusion, we find evidence of past CHIKV transmission in central and southern Vietnam, but no evidence of recent sustained transmission. When transmission of CHIKV did occur, it appeared to be widespread and affect a geographically diverse population. The estimated susceptibility of the population to chikungunya is continually increasing, therefore the possibility of future CHIKV transmission in Vietnam remains.
Phuong, Huynh Thi; Vy, Nguyen Ha Thao; Thanh, Nguyen Thi Le; Lien, Nguyen Thi Nam; Hong, Tran Thi Kim; Dung, Pham Ngoc; Chau, Nguyen Van Vinh; Boni, Maciej F.; Clapham, Hannah E.
2018-01-01
Background Arbovirus infections are a serious concern in tropical countries due to their high levels of transmission and morbidity. With the outbreaks of chikungunya (CHIKV) in surrounding regions in recent years and the fact that the environment in Vietnam is suitable for the vectors of CHIKV, the possibility of transmission of CHIKV in Vietnam is of great interest. However, information about CHIKV activity in Vietnam remains limited. Methodology In order to address this question, we performed a systematic review of CHIKV in Vietnam and a CHIKV seroprevalence survey. The seroprevalence survey tested for CHIKV IgG in population serum samples from individuals of all ages in 2015 from four locations in Vietnam. Principal findings The four locations were An Giang province (n = 137), Ho Chi Minh City (n = 136), Dak Lak province (n = 137), and Hue City (n = 136). The findings give us evidence of some CHIKV activity: 73/546 of overall samples were seropositive (13.4%). The age-adjusted seroprevalences were 12.30% (6.58–18.02), 13.42% (7.16–19.68), 7.97% (3.56–12.38), and 3.72% (1.75–5.69) in An Giang province, Ho Chi Minh City, Dak Lak province, and Hue City respectively. However, the age-stratified seroprevalence suggests that the last transmission ended around 30 years ago, consistent with results from the systematic review. We see no evidence for on-going transmission in three of the locations, though with some evidence of recent exposure in Dak Lak, most likely due to transmission in neighbouring countries. Before the 1980s, when transmission was occurring, we estimate on average 2–4% of the population were infected each year in HCMC and An Giang and Hue (though transmision ended earlier in Hue). We estimate lower transmission in Dak Lak, with around 1% of the population infected each year. Conclusion In conclusion, we find evidence of past CHIKV transmission in central and southern Vietnam, but no evidence of recent sustained transmission. When transmission of CHIKV did occur, it appeared to be widespread and affect a geographically diverse population. The estimated susceptibility of the population to chikungunya is continually increasing, therefore the possibility of future CHIKV transmission in Vietnam remains. PMID:29425199
2015-08-24
SUPPLEMENTARY NOTES 12. DISTRIBUTION AVAILIBILITY STATEMENT 6. AUTHORS 7. PERFORMING ORGANIZATION NAMES AND ADDRESSES 15. SUBJECT TERMS b. ABSTRACT 2...network keeping constraints such as transmission rate, transmission delay, Signal-to-Interference and Noise Ratio (SINR) under consideration. Table...distances. It is advantageous to accomplish such transmission using sensors in a multi-hop relay form keeping constraints such as transmission rate
High risk behavior for HIV transmission among former injecting drug users: a survey from Indonesia.
Iskandar, Shelly; Basar, Diba; Hidayat, Teddy; Siregar, Ike M P; Pinxten, Lucas; van Crevel, Reinout; Van der Ven, Andre J A M; De Jong, Cor A J
2010-08-10
Injecting drug use is an increasingly important cause of HIV transmission in most countries worldwide, especially in eastern Europe, South America, and east and southeast Asia. Among people actively injecting drugs, provision of clean needles and opioid substitution reduce HIV-transmission. However, former injecting drug users (fIDUs) are often overlooked as a high risk group for HIV transmission. We compared HIV risk behavior among current and former injecting drug users (IDUs) in Indonesia, which has a rapidly growing HIV-epidemic largely driven by injecting drug use. Current and former IDUs were recruited by respondent driven sampling in an urban setting in Java, and interviewed regarding drug use and HIV risk behavior using the European Addiction Severity Index and the Blood Borne Virus Transmission Questionnaire. Drug use and HIV transmission risk behavior were compared between current IDUs and former IDUs, using the Mann-Whitney and Pearson Chi-square test. Ninety-two out of 210 participants (44%) were self reported former IDUs. Risk behavior related to sex, tattooing or piercing was common among current as well as former IDUs, 13% of former IDUs were still exposed to contaminated injecting equipment. HIV-infection was high among former (66%) and current (60%) IDUs. Former IDUs may contribute significantly to the HIV-epidemic in Indonesia, and HIV-prevention should therefore also target this group, addressing sexual and other risk behavior.
Dědková, Kateřina; Lang, Jaroslav; Matějová, Kateřina; Peikertová, Pavlína; Holešinský, Jan; Vodárek, Vlastimil; Kukutschová, Jana
2015-08-01
The paper addresses laboratory preparation, characterization and in vitro evaluation of antibacterial activity of graphite/TiO2 nanocomposites. Composites graphite/TiO2 with various ratio of TiO2 nanoparticles (30wt.%, and 50wt.%) to graphite were prepared using a thermal hydrolysis of titanylsulfate in the presence of graphite particles, and subsequently dried at 80°C. X-ray powder diffraction, transmission electron microscopy and Raman microspectroscopy served as phase-analytical methods distinguishing anatase and rutile phases in the prepared composites. Scanning and transmission electron microscopy techniques were used for characterization of morphology of the prepared samples. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity, using four common human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa). Antibacterial activity of the graphite/TiO2 nanocomposites could be based mainly on photocatalytic reaction with subsequent potential interaction of reactive oxygen species with bacterial cells. During the antibacterial activity experiments, the graphite/TiO2 nanocomposites exhibited antibacterial activity, where differences in the onset of activity and activity against bacterial strains were observed. The highest antibacterial activity evaluated as minimum inhibitory concentration was observed against P. aeruginosa after 180min of irradiation. Copyright © 2015 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Valentine, Timothy E.; Leal, Luiz C.; Guber, Klaus H.
2002-12-01
The Department of Energy established the Nuclear Criticality Safety Program (NCSP) in response to the Recommendation 97-2 by the Defense Nuclear Facilities Safety Board. The NCSP consists of seven elements of which nuclear data measurements and evaluations is a key component. The intent of the nuclear data activities is to provide high resolution nuclear data measurements that are evaluated, validated, and formatted for use by the nuclear criticality safety community to provide improved and reliable calculations for nuclear criticality safety evaluations. High resolution capture, fission, and transmission measurements are performed at the Oak Ridge Electron Linear Accelerator (ORELA) to address the needs of the criticality safety community and to address known deficiencies in nuclear data evaluations. The activities at ORELA include measurements on both light and heavy nuclei and have been used to identify improvements in measurement techniques that greatly improve the measurement of small capture cross sections. The measurement activities at ORELA provide precise and reliable high-resolution nuclear data for the nuclear criticality safety community.
Zika Virus -10 Public Health Achievements in 2016 and Future Priorities.
Oussayef, Nadia L; Pillai, Satish K; Honein, Margaret A; Ben Beard, C; Bell, Beth; Boyle, Coleen A; Eisen, Lars M; Kohl, Katrin; Kuehnert, Matthew J; Lathrop, Eva; Martin, Stacey W; Martin, Rebecca; McAllister, Janet C; McClune, Elizabeth Pantino; Mead, Paul; Meaney-Delman, Dana; Petersen, Brett; Petersen, Lyle R; Polen, Kara N D; Powers, Ann M; Redd, Stephen C; Sejvar, James J; Sharp, Tyler; Villanueva, Julie; Jamieson, Denise J
2017-01-06
The introduction of Zika virus into the Region of the Americas (Americas) and the subsequent increase in cases of congenital microcephaly resulted in activation of CDC's Emergency Operations Center on January 22, 2016, to ensure a coordinated response and timely dissemination of information, and led the World Health Organization to declare a Public Health Emergency of International Concern on February 1, 2016. During the past year, public health agencies and researchers worldwide have collaborated to protect pregnant women, inform clinicians and the public, and advance knowledge about Zika virus (Figure 1). This report summarizes 10 important contributions toward addressing the threat posed by Zika virus in 2016. To protect pregnant women and their fetuses and infants from the effects of Zika virus infection during pregnancy, public health activities must focus on preventing mosquito-borne transmission through vector control and personal protective practices, preventing sexual transmission by advising abstention from sex or consistent and correct use of condoms, and preventing unintended pregnancies by reducing barriers to access to highly effective reversible contraception.
Paratransgenic Control of Vector Borne Diseases
Hurwitz, Ivy; Fieck, Annabeth; Read, Amber; Hillesland, Heidi; Klein, Nichole; Kang, Angray; Durvasula, Ravi
2011-01-01
Conventional methodologies to control vector borne diseases with chemical pesticides are often associated with environmental toxicity, adverse effects on human health and the emergence of insect resistance. In the paratransgenic strategy, symbiotic or commensal microbes of host insects are transformed to express gene products that interfere with pathogen transmission. These genetically altered microbes are re-introduced back to the insect where expression of the engineered molecules decreases the host's ability to transmit the pathogen. We have successfully utilized this strategy to reduce carriage rates of Trypanosoma cruzi, the causative agent of Chagas disease, in the triatomine bug, Rhodnius prolixus, and are currently developing this methodology to control the transmission of Leishmania donovani by the sand fly Phlebotomus argentipes. Several effector molecules, including antimicrobial peptides and highly specific single chain antibodies, are currently being explored for their anti-parasite activities in these two systems. In preparation for eventual field use, we are actively engaged in risk assessment studies addressing the issue of horizontal gene transfer from the modified bacteria to environmental microbes. PMID:22110385
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuiper, James A; Krummel, John R; Hlava, Kevin J
2014-03-25
As has been noted in many reports and publications, acquiring new or expanded rights-of-way for transmission is a challenging process, because numerous land use and land ownership constraints must be overcome to develop pathways suitable for energy transmission infrastructure. In the eastern U.S., more than twenty federally protected national trails (some of which are thousands of miles long, and cross many states) pose a potential obstacle to the development of new or expanded electricity transmission capacity. However, the scope of this potential problem is not well-documented, and there is no baseline information available that could allow all stakeholders to studymore » routing scenarios that could mitigate impacts on national trails. This report, Electricity Transmission, Pipelines, and National Trails: An Analysis of Current and Potential Intersections on Federal Lands in the Eastern United States, was prepared by the Environmental Science Division of Argonne National Laboratory (Argonne). Argonne was tasked by DOE to analyze the “footprint” of the current network of National Historic and Scenic Trails and the electricity transmission system in the 37 eastern contiguous states, Alaska, and Hawaii; assess the extent to which national trails are affected by electrical transmission; and investigate the extent to which national trails and other sensitive land use types may be affected in the near future by planned transmission lines. Pipelines are secondary to transmission lines for analysis, but are also within the analysis scope in connection with the overall directives of Section 368 of the Energy Policy Act of 2005, and because of the potential for electrical transmission lines being collocated with pipelines. Based on Platts electrical transmission line data, a total of 101 existing intersections with national trails on federal land were found, and 20 proposed intersections. Transmission lines and pipelines are proposed in Alaska; however there are no locations that intersect national trails. Source data did not indicate any planned transmission lines or pipelines in Hawaii. A map atlas provides more detailed mapping of the topics investigated in this study, and the accompanying GIS database provides the baseline information for further investigating locations of interest. In many cases the locations of proposed transmission lines are not accurately mapped (or a specific route may not yet be determined), and accordingly the specific crossing locations are speculative. However since both national trails and electrical transmission lines are long linear systems, the characteristics of the crossings reported in this study are expected to be similar to both observed characteristics of the existing infrastructure provided in this report, and of the new infrastructure if these proposed projects are built. More focused study of these siting challenges is expected to mitigate some of potential impacts by choosing routes that minimize or eliminate them. The current study primarily addresses a set of screening-level characterizations that provide insights into how the National Trail System may influence the siting of energy transport facilities in the states identified under Section 368(b) of the Energy Policy Act of 2005. As such, it initializes gathering and beginning analysis of the primary environmental and energy data, and maps the contextual relationships between an important national environmental asset and how this asset intersects with energy planning activities. Thus the current study sets the stage for more in-depth analyses and data development activities that begin to solve key transmission siting constraints. Our recommendations for future work incorporate two major areas: (1) database development and analytics and (2) modeling and scenario analysis for energy planning. These recommendations provide a path forward to address key issues originally developed under the Energy Policy Act of 2005 that are now being carried forward under the President’s Climate Action Plan.« less
Gerardin, Jaline; Bever, Caitlin A; Bridenbecker, Daniel; Hamainza, Busiku; Silumbe, Kafula; Miller, John M; Eisele, Thomas P; Eckhoff, Philip A; Wenger, Edward A
2017-06-12
Reactive case detection could be a powerful tool in malaria elimination, as it selectively targets transmission pockets. However, field operations have yet to demonstrate under which conditions, if any, reactive case detection is best poised to push a region to elimination. This study uses mathematical modelling to assess how baseline transmission intensity and local interconnectedness affect the impact of reactive activities in the context of other possible intervention packages. Communities in Southern Province, Zambia, where elimination operations are currently underway, were used as representatives of three archetypes of malaria transmission: low-transmission, high household density; high-transmission, low household density; and high-transmission, high household density. Transmission at the spatially-connected household level was simulated with a dynamical model of malaria transmission, and local variation in vectorial capacity and intervention coverage were parameterized according to data collected from the area. Various potential intervention packages were imposed on each of the archetypical settings and the resulting likelihoods of elimination by the end of 2020 were compared. Simulations predict that success of elimination campaigns in both low- and high-transmission areas is strongly dependent on stemming the flow of imported infections, underscoring the need for regional-scale strategies capable of reducing transmission concurrently across many connected areas. In historically low-transmission areas, treatment of clinical malaria should form the cornerstone of elimination operations, as most malaria infections in these areas are symptomatic and onward transmission would be mitigated through health system strengthening; reactive case detection has minimal impact in these settings. In historically high-transmission areas, vector control and case management are crucial for limiting outbreak size, and the asymptomatic reservoir must be addressed through reactive case detection or mass drug campaigns. Reactive case detection is recommended only for settings where transmission has recently been reduced rather than all low-transmission settings. This is demonstrated in a modelling framework with strong out-of-sample accuracy across a range of transmission settings while including methodologies for understanding the most resource-effective allocations of health workers. This approach generalizes to providing a platform for planning rational scale-up of health systems based on locally-optimized impact according to simplified stratification.
Role of microglia in methamphetamine-induced neurotoxicity
Xu, Enquan; Liu, Jianuo; Liu, Han; Wang, Xiaobei; Xiong, Huangui
2017-01-01
Methamphetamine (Meth) is an addictive psychostimulant widely abused around the world. The chronic use of Meth produces neurotoxicity featured by dopaminergic terminal damage and microgliosis, resulting in serious neurological and behavioral consequences. Ample evidence indicate that Meth causes microglial activation and resultant secretion of pro-inflammatory molecules leading to neural injury. However, the mechanisms underlying Meth-induced microglial activation remain to be determined. In this review, we attempt to address the effects of Meth on human immunodeficiency virus (HIV)-associated microglia activation both in vitro and in-vivo. Meth abuse not only increases HIV transmission but also exacerbates progression of HIV-associated neurocognitive disorders (HAND) through activation of microglia. In addition, the therapeutic potential of anti-inflammatory drugs on ameliorating Meth-induced microglia activation and resultant neuronal injury is discussed. PMID:28694920
Adam, Barry D; Gardner, Sandra; Major, Carol; Campbell, Diana; Light, Lucia; Globerman, Jason
2016-01-01
This article reports on a social marketing campaign directed toward high-risk men who have sex with men in Toronto and Ottawa to encourage testing for HIV and syphilis; improve knowledge about HIV transmission, seroconversion symptoms, and the HIV window period; and heighten awareness of syphilis transmission and its relationship to facilitating HIV transmission. Evaluation data were collected from a large-scale online pre-and postcampaign survey of sexually active men who have sex with men and from laboratory testing data. Men who turned up to be tested also filled out an exit survey. The campaign websites attracted some 15,000 unique visitors, 54% of whom had an IP address in Toronto or Ottawa. Laboratory data showed a 20% increase in HIV testing in Toronto over the campaign compared to the previous year. The overall rate of HIV-positive tests remained relatively constant. Knowledge levels about seroconversion symptoms, sexually transmitted infection and HIV transmission, and the HIV window period were significantly better among postcampaign survey respondents aware of the campaign compared to postcampaign respondents who were not aware and compared to precampaign respondents. © 2015 Society for Public Health Education.
Rönn, Minttu M; Wolf, Emory E; Chesson, Harrell; Menzies, Nicolas A; Galer, Kara; Gorwitz, Rachel; Gift, Thomas; Hsu, Katherine; Salomon, Joshua A
2017-05-01
Mathematical models of chlamydia transmission can help inform disease control policy decisions when direct empirical evaluation of alternatives is impractical. We reviewed published chlamydia models to understand the range of approaches used for policy analyses and how the studies have responded to developments in the field. We performed a literature review by searching Medline and Google Scholar (up to October 2015) to identify publications describing dynamic chlamydia transmission models used to address public health policy questions. We extracted information on modeling methodology, interventions, and key findings. We identified 47 publications (including two model comparison studies), which reported collectively on 29 distinct mathematical models. Nine models were individual-based, and 20 were deterministic compartmental models. The earliest studies evaluated the benefits of national-level screening programs and predicted potentially large benefits from increased screening. Subsequent trials and further modeling analyses suggested the impact might have been overestimated. Partner notification has been increasingly evaluated in mathematical modeling, whereas behavioral interventions have received relatively limited attention. Our review provides an overview of chlamydia transmission models and gives a perspective on how mathematical modeling has responded to increasing empirical evidence and addressed policy questions related to prevention of chlamydia infection and sequelae.
Bazargan, M.; Kelly, E. M.; Stein, J. A.; Husaini, B. A.; Bazargan, S. H.
2000-01-01
This study identifies theoretically based predictors of condom use in a sample of 253 sexually active African-American college students recruited from two historically African-American colleges. The Information-Motivation-Behavioral (IMB) skills model of AIDS-preventive behavior was employed to delineate the roles of HIV/AIDS knowledge, experiences with and attitudes toward condom use, peer influences, perceived vulnerability, monogamy, and behavioral skills. A predictive structural equation model revealed significant predictors of more condom use including: male gender, more sexual HIV knowledge, positive experiences and attitudes about condom use, nonmonogamy, and greater behavioral skills. Results imply that attention to behavioral skills for negotiating safer sex and training in the proper use of condoms are key elements in reducing high risk behaviors. Increasing the specific knowledge level of college students regarding the subtleties of sexual transmission of HIV is important and should be addressed. Heightening students' awareness of the limited protection of serial monogamy, and the need to address gender-specific training regarding required behavior change to reduce transmission of HIV should be an additional goal of college health professionals. PMID:10992684
Pregnant adolescents living with HIV: what we know, what we need to know, where we need to go.
Callahan, Tegan; Modi, Surbhi; Swanson, Jennifer; Ng'eno, Bernadette; Broyles, Laura N
2017-08-04
HIV-infected pregnant and breastfeeding adolescents are a particularly vulnerable group that require special attention and enhanced support to achieve optimal maternal and infant outcomes. The objective of this paper is to review published evidence about antenatal care (ANC) service delivery and outcomes for HIV-infected pregnant adolescents in low-income country settings, identify gaps in knowledge and programme services and highlight the way forward to improve clinical outcomes of this vulnerable group. Emerging data from programmes in sub-Saharan Africa highlight that HIV-infected pregnant adolescents have poorer prevention of mother-to-child HIV transmission (PMTCT) service outcomes, including lower PMTCT service uptake, compared to HIV-infected pregnant adults. In addition, the limited evidence available suggests that there may be higher rates of mother-to-child HIV transmission among infants of HIV-infected pregnant adolescents. While the reasons for the inferior outcomes among adolescents in ANC need to be further explored and addressed, there is sufficient evidence that immediate operational changes are needed to address the unique needs of this population. Such changes could include integration of adolescent-friendly services into PMTCT settings or targeting HIV-infected pregnant adolescents with enhanced retention and follow-up activities.
Impact of scabies in resource-poor communities.
Heukelbach, Jorg; Mazigo, Humphrey D; Ugbomoiko, Uade S
2013-04-01
Features of endemic scabies are specific in resource-poor and underprivileged communities, with implications for control measures on the community level. In this review, these special aspects are addressed. Scabies is endemic in many resource-poor communities, with a prevalence of 20% and higher. Transmission is influenced by social attitudes, migration, access to healthcare services, housing conditions, hygiene conditions, and crowding. Endemic scabies occurs with severe infestations, complications, and sequels, mainly in children. Sleep loss as a result of scabies-related itching is common. Complications include secondary infections by group A streptococci and acute poststreptococcal glomerulonephritis. Shame, restriction of leisure activities, and stigmatization are common. Treatment of scabies includes a variety of topical compounds, but control on the community level is not an easy task. As ivermectin kills a variety of other parasites, this oral drug is increasingly used for mass treatment. Intervention should address socioemotional aspects using an integrated approach with professionals from different areas, and the community. Scabies is a neglected disease and needs to be perceived as an important public health problem causing morbidity in many resource-poor communities. Future work on epidemiology, clinical aspects, transmission dynamics, socioeconomic aspects, and sustainable control in resource-poor communities is needed.
Brock, P M; Fornace, K M; Parmiter, M; Cox, J; Drakeley, C J; Ferguson, H M; Kao, R R
2016-04-01
The public health threat posed by zoonotic Plasmodium knowlesi appears to be growing: it is increasingly reported across South East Asia, and is the leading cause of malaria in Malaysian Borneo. Plasmodium knowlesi threatens progress towards malaria elimination as aspects of its transmission, such as spillover from wildlife reservoirs and reliance on outdoor-biting vectors, may limit the effectiveness of conventional methods of malaria control. The development of new quantitative approaches that address the ecological complexity of P. knowlesi, particularly through a focus on its primary reservoir hosts, will be required to control it. Here, we review what is known about P. knowlesi transmission, identify key knowledge gaps in the context of current approaches to transmission modelling, and discuss the integration of these approaches with clinical parasitology and geostatistical analysis. We highlight the need to incorporate the influences of fine-scale spatial variation, rapid changes to the landscape, and reservoir population and transmission dynamics. The proposed integrated approach would address the unique challenges posed by malaria as a zoonosis, aid the identification of transmission hotspots, provide insight into the mechanistic links between incidence and land use change and support the design of appropriate interventions.
Mistry, Rupal; Kounatidis, Ilias; Ligoxygakis, Petros
2017-01-01
Resident gut bacteria are constantly influencing the immune system, yet the role of the immune system in shaping microbiota composition during an organism’s life span has remained unclear. Experiments in mice have been inconclusive due to differences in husbandry schemes that led to conflicting results. We used Drosophila as a genetically tractable system with a simpler gut bacterial population structure streamlined genetic backgrounds and established cross schemes to address this issue. We found that, depending on their genetic background, young flies had microbiota of different diversities that converged with age to the same Acetobacteraceae-dominated pattern in healthy flies. This pattern was accelerated in immune-compromised flies with higher bacterial load and gut cell death. Nevertheless, immune-compromised flies resembled their genetic background, indicating that familial transmission was the main force regulating gut microbiota. In contrast, flies with a constitutively active immune system had microbiota readily distinguishable from their genetic background with the introduction and establishment of previously undetectable bacterial families. This indicated the influence of immunity over familial transmission. Moreover, hyperactive immunity and increased enterocyte death resulted in the highest bacterial load observed starting from early adulthood. Cohousing experiments showed that the microenvironment also played an important role in the structure of the microbiota where flies with constitutive immunity defined the gut microbiota of their cohabitants. Our data show that, in Drosophila, constitutively active immunity shapes the structure and density of gut microbiota. PMID:28413160
NASA Astrophysics Data System (ADS)
Campolina, Bruno L.
The prediction of aircraft interior noise involves the vibroacoustic modelling of the fuselage with noise control treatments. This structure is composed of a stiffened metallic or composite panel, lined with a thermal and acoustic insulation layer (glass wool), and structurally connected via vibration isolators to a commercial lining panel (trim). The goal of this work aims at tailoring the noise control treatments taking design constraints such as weight and space optimization into account. For this purpose, a representative aircraft double-wall is modelled using the Statistical Energy Analysis (SEA) method. Laboratory excitations such as diffuse acoustic field and point force are addressed and trends are derived for applications under in-flight conditions, considering turbulent boundary layer excitation. The effect of the porous layer compression is firstly addressed. In aeronautical applications, compression can result from the installation of equipment and cables. It is studied analytically and experimentally, using a single panel and a fibrous uniformly compressed over 100% of its surface. When compression increases, a degradation of the transmission loss up to 5 dB for a 50% compression of the porous thickness is observed mainly in the mid-frequency range (around 800 Hz). However, for realistic cases, the effect should be reduced since the compression rate is lower and compression occurs locally. Then the transmission through structural connections between panels is addressed using a four-pole approach that links the force-velocity pair at each side of the connection. The modelling integrates experimental dynamic stiffness of isolators, derived using an adapted test rig. The structural transmission is then experimentally validated and included in the double-wall SEA model as an equivalent coupling loss factor (CLF) between panels. The tested structures being flat, only axial transmission is addressed. Finally, the dominant sound transmission paths are identified in the 100 Hz to 10 kHz frequency range for double-walls under diffuse acoustic field and under point-force excitations. Non-resonant transmission is higher at low frequencies (frequencies lower than 1 kHz) while the structure-borne and the airborne paths dominate at mid- and high-frequencies, around 1 kHz and higher, respectively. An experimental validation on double-walls shows that the model is able to predict changes in the overall transmission caused by different structural couplings (rigid coupling, coupling via isolators and structurally uncoupled). Noise reduction means adapted to each transmission path, such as absorption, dissipation and structural decoupling, may be then derived. Keywords: Statistical energy analysis, Vibration isolator, Double-wall, Transfer path analysis, Transmission Loss.
Computer Networks and Networking: A Primer.
ERIC Educational Resources Information Center
Collins, Mauri P.
1993-01-01
Provides a basic introduction to computer networks and networking terminology. Topics addressed include modems; the Internet; TCP/IP (Transmission Control Protocol/Internet Protocol); transmission lines; Internet Protocol numbers; network traffic; Fidonet; file transfer protocol (FTP); TELNET; electronic mail; discussion groups; LISTSERV; USENET;…
46 CFR Exhibit No. 1 to Subpart B... - Notice of Appearance
Code of Federal Regulations, 2010 CFR
2010-10-01
... when you call, appropriate advice left with my office will suffice.) [] facsimile transmission [] electronic mail [Name] [Address] [Telephone No.] [Fax No.] [E-mail address] [Signature] [64 FR 7807, Feb. 17...
Combination sound and vibration isolation curb for rooftop air-handling systems
NASA Astrophysics Data System (ADS)
Paige, Thomas S.
2005-09-01
This paper introduces the new Model ESSR Sound and Vibration Isolation Curb manufactured by Kinetics Noise Control, Inc. This product was specially designed to address all of the common transmission paths associated with noise and vibration sources from roof-mounted air-handling equipment. These include: reduction of airborne fan noise in supply and return air ductwork, reduction of duct rumble and breakout noise, reduction of direct airborne sound transmission through the roof deck, and reduction of vibration and structure-borne noise transmission to the building structure. Upgrade options are available for increased seismic restraint and wind-load protection. The advantages of this new system over the conventional approach of installing separate duct silencers in the room ceiling space below the rooftop unit are discussed. Several case studies are presented with the emphasis on completed projects pertaining to classrooms and school auditorium applications. Some success has also been achieved by adding active noise control components to improve low-frequency attenuation. This is an innovative product designed for conformance with the new classroom acoustics standard ANSI S12.60.
Wildlife and electric power transmission
Ellis, D.H.; Goodwin, J.G.; Hunt, J.R.; Fletcher, John L.; Busnel, R.G.
1978-01-01
Hundreds of thousands of miles of transmission lines have been introduced into our natural environment. These lines and their corridors can be damaging or beneficial to wildlife communities depending on how they are designed, where they are placed, and when they are constructed and maintained. With the current trend toward UHV systems, new problems (associated with additional increments in audible noise, electric and magnetic force fields, etc.) must be addressed. We recommend the following areas for careful study: (1) the response of wilderness species to transmission lines and line construction and maintenance activities (2) the magnitude of bird collision and electrocution mortality, (3) the response of power corridor and power tower in habiting wildlife to laboratory and field doses of electro-chemical oxidants, corona noise, electric and magnetic fields, etc., (4) the productivity of tower inhabiting birds compared with nearby non-tower nesters, and (5) the influence of powerline corridors on mammalian and avian migration patterns. It is our hope that the questions identified in this study will help stimulate further research so that we can maximize wildlife benefits and minimize wildlife detriments.
Brown, Alexandra E; Okayasu, Hiromasa; Nzioki, Michael M; Wadood, Mufti Z; Chabot-Couture, Guillaume; Quddus, Arshad; Walker, George; Sutter, Roland W
2014-11-01
Monitoring the quality of supplementary immunization activities (SIAs) is a key tool for polio eradication. Regular monitoring data, however, are often unreliable, showing high coverage levels in virtually all areas, including those with ongoing virus circulation. To address this challenge, lot quality assurance sampling (LQAS) was introduced in 2009 as an additional tool to monitor SIA quality. Now used in 8 countries, LQAS provides a number of programmatic benefits: identifying areas of weak coverage quality with statistical reliability, differentiating areas of varying coverage with greater precision, and allowing for trend analysis of campaign quality. LQAS also accommodates changes to survey format, interpretation thresholds, evaluations of sample size, and data collection through mobile phones to improve timeliness of reporting and allow for visualization of campaign quality. LQAS becomes increasingly important to address remaining gaps in SIA quality and help focus resources on high-risk areas to prevent the continued transmission of wild poliovirus. © Crown copyright 2014.
Radiofrequency pulse design in parallel transmission under strict temperature constraints.
Boulant, Nicolas; Massire, Aurélien; Amadon, Alexis; Vignaud, Alexandre
2014-09-01
To gain radiofrequency (RF) pulse performance by directly addressing the temperature constraints, as opposed to the specific absorption rate (SAR) constraints, in parallel transmission at ultra-high field. The magnitude least-squares RF pulse design problem under hard SAR constraints was solved repeatedly by using the virtual observation points and an active-set algorithm. The SAR constraints were updated at each iteration based on the result of a thermal simulation. The numerical study was performed for an SAR-demanding and simplified time of flight sequence using B1 and ΔB0 maps obtained in vivo on a human brain at 7T. The proposed adjustment of the SAR constraints combined with an active-set algorithm provided higher flexibility in RF pulse design within a reasonable time. The modifications of those constraints acted directly upon the thermal response as desired. Although further confidence in the thermal models is needed, this study shows that RF pulse design under strict temperature constraints is within reach, allowing better RF pulse performance and faster acquisitions at ultra-high fields at the cost of higher sequence complexity. Copyright © 2013 Wiley Periodicals, Inc.
de Souza, Wanderley; de Carvalho, Tecia M. Ulisses
2013-01-01
In the present short review, we analyze past experiments that addressed the interactions of intracellular pathogenic protozoa (Trypanosoma cruzi, Toxoplasma gondii, and Plasmodium) with host cells and the initial use of the term active penetration to indicate that a protozoan “crossed the host cell membrane, penetrating into the cytoplasm.” However, the subsequent use of transmission electron microscopy showed that, for all of the protozoans and cell types examined, endocytosis, classically defined as involving the formation of a membrane-bound vacuole, took place during the interaction process. As a consequence, the recently penetrated parasites are always within a vacuole, designated the parasitophorous vacuole (PV). PMID:23355838
Aktar, Evin; Nikolić, Milica; Bögels, Susan M.
2017-01-01
Generalized anxiety disorder (GAD) runs in families. Building on recent theoretical approaches, this review focuses on potential environmental pathways for parent-to-child transmission of GAD. First, we address child acquisition of a generalized pattern of fearful/anxious and avoidant responding to potential threat from parents via verbal information and via modeling. Next, we address how parenting behaviors may contribute to maintenance of fearful/anxious and avoidant reactions in children. Finally, we consider intergenerational transmission of worries as a way of coping with experiential avoidance of strong negative emotions and with intolerance of uncertainty. We conclude that parents with GAD may bias their children's processing of potential threats in the environment by conveying the message that the world is not safe, that uncertainty is intolerable, that strong emotions should be avoided, and that worry helps to cope with uncertainty, thereby transmitting cognitive styles that characterize GAD. Our review highlights the need for research on specific pathways for parent-to-child transmission of GAD. PMID:28867938
Aktar, Evin; Nikolić, Milica; Bögels, Susan M
2017-06-01
Generalized anxiety disorder (GAD) runs in families. Building on recent theoretical approaches, this review focuses on potential environmental pathways for parent-to-child transmission of GAD. First, we address child acquisition of a generalized pattern of fearful/anxious and avoidant responding to potential threat from parents via verbal information and via modeling. Next, we address how parenting behaviors may contribute to maintenance of fearful/anxious and avoidant reactions in children. Finally, we consider intergenerational transmission of worries as a way of coping with experiential avoidance of strong negative emotions and with intolerance of uncertainty. We conclude that parents with GAD may bias their children's processing of potential threats in the environment by conveying the message that the world is not safe, that uncertainty is intolerable, that strong emotions should be avoided, and that worry helps to cope with uncertainty, thereby transmitting cognitive styles that characterize GAD. Our review highlights the need for research on specific pathways for parent-to-child transmission of GAD.
Ang, Lei Yin Emily; Too, Horng Khit Issac; Tan, Eng Lee; Chow, Tak-Kwong Vincent; Shek, Lynette Pei-Chi; Tham, Elizabeth Huiwen; Alonso, Sylvie
2016-06-24
Recurrence of hand, foot and mouth disease (HFMD) pandemics continues to threaten public health. Despite increasing awareness and efforts, effective vaccine and drug treatment have yet to be available. Probiotics have gained recognition in the field of healthcare worldwide, and have been extensively prescribed to babies and young children to relieve gastrointestinal (GI) disturbances and diseases, associated or not with microbial infections. Since the faecal-oral axis represents the major route of HFMD transmission, transient persistence of probiotic bacteria in the GI tract may confer some protection against HFMD and limit transmission among children. In this work, the antiviral activity of two commercially available probiotics, namely Lactobacillus reuteri Protectis (L. reuteri Protectis) and Lactobacillus casei Shirota (L. casei Shirota), was assayed against Coxsackieviruses and Enterovirus 71 (EV71), the main agents responsible for HFMD. In vitro infection set-ups using human skeletal muscle and colon cell lines were designed to assess the antiviral effect of the probiotic bacteria during entry and post-entry steps of the infection cycle. Our findings indicate that L. reuteri Protectis displays a significant dose-dependent antiviral activity against Coxsackievirus type A (CA) strain 6 (CA6), CA16 and EV71, but not against Coxsackievirus type B strain 2. Our data support that the antiviral effect is likely achieved through direct physical interaction between bacteria and virus particles, which impairs virus entry into its mammalian host cell. In contrast, no significant antiviral effect was observed with L. casei Shirota. Should the antiviral activity of L. reuteri Protectis observed in vitro be translated in vivo, such probiotics-based therapeutic approach may have the potential to address the urgent need for a safe and effective means to protect against HFMD and limit its transmission among children.
Piantadosi, Patrick T; Floresco, Stan B
2014-01-01
Inhibitory gamma-aminobutyric acid (GABA) transmission within the prefrontal cortex (PFC) regulates numerous functions, and perturbations in GABAergic transmission within this region have been proposed to contribute to some of the cognitive and behavioral abnormalities associated with disorders such as schizophrenia. These abnormalities include deficits in emotional regulation and aberrant attributions of affective salience. Yet, how PFC GABA regulates these types of emotional processes are unclear. To address this issue, we investigated the contribution of PFC GABA transmission to different aspects of Pavlovian emotional learning in rats using translational discriminative fear conditioning and latent inhibition (LI) assays. Reducing prelimbic PFC GABAA transmission via infusions of the antagonist bicuculline before the acquisition or expression of fear conditioning eliminated the ability to discriminate between an aversive conditioned stimulus (CS+) paired with footshock vs a neutral CS–, resembling similar deficits observed in schizophrenic patients. In a separate experiment, blockade of PFC GABAA receptors before CS preexposure (PE) and conditioning did not affect subsequent expression of LI, but did enhance fear in rats that were not preexposed to the CS. In contrast, PFC GABA-blockade before a fear expression test disrupted the recall of learned irrelevance and abolished LI. These data suggest that normal PFC GABA transmission is critical for regulating and mitigating multiple aspects of aversive learning, including discrimination between fear vs safety signals and recall of information about the irrelevance of stimuli. Furthermore, they suggest that similar deficits in emotional regulation observed in schizophrenia may be driven in part by deficient PFC GABA activity. PMID:24784549
Piantadosi, Patrick T; Floresco, Stan B
2014-09-01
Inhibitory gamma-aminobutyric acid (GABA) transmission within the prefrontal cortex (PFC) regulates numerous functions, and perturbations in GABAergic transmission within this region have been proposed to contribute to some of the cognitive and behavioral abnormalities associated with disorders such as schizophrenia. These abnormalities include deficits in emotional regulation and aberrant attributions of affective salience. Yet, how PFC GABA regulates these types of emotional processes are unclear. To address this issue, we investigated the contribution of PFC GABA transmission to different aspects of Pavlovian emotional learning in rats using translational discriminative fear conditioning and latent inhibition (LI) assays. Reducing prelimbic PFC GABAA transmission via infusions of the antagonist bicuculline before the acquisition or expression of fear conditioning eliminated the ability to discriminate between an aversive conditioned stimulus (CS+) paired with footshock vs a neutral CS-, resembling similar deficits observed in schizophrenic patients. In a separate experiment, blockade of PFC GABAA receptors before CS preexposure (PE) and conditioning did not affect subsequent expression of LI, but did enhance fear in rats that were not preexposed to the CS. In contrast, PFC GABA-blockade before a fear expression test disrupted the recall of learned irrelevance and abolished LI. These data suggest that normal PFC GABA transmission is critical for regulating and mitigating multiple aspects of aversive learning, including discrimination between fear vs safety signals and recall of information about the irrelevance of stimuli. Furthermore, they suggest that similar deficits in emotional regulation observed in schizophrenia may be driven in part by deficient PFC GABA activity.
Applications of ISES for coastal zone studies
NASA Technical Reports Server (NTRS)
Bartlett, D. S.
1990-01-01
In contrast to the discipline- and process-oriented topics addressed, coastal zone studies are defined geographically by the special circumstances inherent in the interface between land and water. The characteristics of coastal zones which make them worthy of separate consideration are: (1) the dynamic nature of natural and anthropogenic processes taking place; (2) the relatively restricted spatial domain of the narrow land/water interface; and (3) the large proportion of the Earth's population living within coastal zones, and the resulting extreme pressure on natural and human resources. These characteristics place special constraints and priorities on remote sensing applications, even though the applications themselves bear close relation to those addressed by other elements of this report (e.g., oceans, ice, vegetation/land use). The discussion which follows first describes the suite of remote sensing activities relevant to coastal zone studies. Potential Information Sciences Experiment System (ISES) experiments will then be addressed within two general categories: applications of real-time data transmission and applications of onboard data acquisition and processing.
NASA Technical Reports Server (NTRS)
Conway, Edmund J.
1992-01-01
An overview of previous studies related to laser power transmission is presented. Particular attention is given to the use of solar pumped lasers for space power applications. Three general laser mechanisms are addressed: photodissociation lasing driven by sunlight, photoexcitation lasing driven directly by sunlight, and photoexcitation lasing driven by thermal radiation.
78 FR 14654 - Standards for Business Practices and Communication Protocols for Public Utilities
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-07
... also require each regional transmission organization (RTO) and independent system operator (ISO) to... 20426, (202) 502-6404. Mindi Sauter (legal issues), Office of the General Counsel, Federal Energy... require each regional transmission organization (RTO) and independent system operator (ISO) to address in...
Crankshaw, Tamaryn L.; Matthews, Lynn T.; Giddy, Janet; Kaida, Angela; Ware, Norma C.; Smit, Jennifer A.; Bangsberg, David R.
2013-01-01
Integrated reproductive health services for people living with HIV must address their fertility intentions. For HIV-serodiscordant couples who want to conceive, attempted conception confers a substantial risk of HIV transmission to the uninfected partner. Behavioral and pharmacologic strategies may reduce HIV transmission risk among HIV-serodiscordant couples who seek to conceive. In order to develop effective pharmaco-behavioral programs, it is important to understand and address the contexts surrounding reproductive decision-making; perceived periconception HIV transmission risk; and periconception risk behaviors. We present a conceptual framework to describe the dynamics involved in periconception HIV risk behaviors in a South African setting. We adapt the Information-Motivation-Behavioral Skill Model of HIV Preventative Behavior to address the structural, individual and couple-level determinants of safer conception behavior. The framework is intended to identify factors that influence periconception HIV risk behavior among serodiscordant couples, and therefore to guide design and implementation of integrated and effective HIV, reproductive health and family planning services that support reproductive decision-making. PMID:23177680
A Vision for Co-optimized T&D System Interaction with Renewables and Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Lindsay; Zéphyr, Luckny; Cardell, Judith B.
The evolution of the power system to the reliable, efficient and sustainable system of the future will involve development of both demand- and supply-side technology and operations. The use of demand response to counterbalance the intermittency of renewable generation brings the consumer into the spotlight. Though individual consumers are interconnected at the low-voltage distribution system, these resources are typically modeled as variables at the transmission network level. In this paper, a vision for cooptimized interaction of distribution systems, or microgrids, with the high-voltage transmission system is described. In this framework, microgrids encompass consumers, distributed renewables and storage. The energy managementmore » system of the microgrid can also sell (buy) excess (necessary) energy from the transmission system. Preliminary work explores price mechanisms to manage the microgrid and its interactions with the transmission system. Wholesale market operations are addressed through the development of scalable stochastic optimization methods that provide the ability to co-optimize interactions between the transmission and distribution systems. Modeling challenges of the co-optimization are addressed via solution methods for large-scale stochastic optimization, including decomposition and stochastic dual dynamic programming.« less
A Vision for Co-optimized T&D System Interaction with Renewables and Demand Response
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, C. Lindsay; Zéphyr, Luckny; Liu, Jialin
The evolution of the power system to the reliable, effi- cient and sustainable system of the future will involve development of both demand- and supply-side technology and operations. The use of demand response to counterbalance the intermittency of re- newable generation brings the consumer into the spotlight. Though individual consumers are interconnected at the low-voltage distri- bution system, these resources are typically modeled as variables at the transmission network level. In this paper, a vision for co- optimized interaction of distribution systems, or microgrids, with the high-voltage transmission system is described. In this frame- work, microgrids encompass consumers, distributed renewablesmore » and storage. The energy management system of the microgrid can also sell (buy) excess (necessary) energy from the transmission system. Preliminary work explores price mechanisms to manage the microgrid and its interactions with the transmission system. Wholesale market operations are addressed through the devel- opment of scalable stochastic optimization methods that provide the ability to co-optimize interactions between the transmission and distribution systems. Modeling challenges of the co-optimization are addressed via solution methods for large-scale stochastic op- timization, including decomposition and stochastic dual dynamic programming.« less
Mapping influenza transmission in the ferret model to transmission in humans
Buhnerkempe, Michael G; Gostic, Katelyn; Park, Miran; Ahsan, Prianna; Belser, Jessica A; Lloyd-Smith, James O
2015-01-01
The controversy surrounding 'gain-of-function' experiments on high-consequence avian influenza viruses has highlighted the role of ferret transmission experiments in studying the transmission potential of novel influenza strains. However, the mapping between influenza transmission in ferrets and in humans is unsubstantiated. We address this gap by compiling and analyzing 240 estimates of influenza transmission in ferrets and humans. We demonstrate that estimates of ferret secondary attack rate (SAR) explain 66% of the variation in human SAR estimates at the subtype level. Further analysis shows that ferret transmission experiments have potential to identify influenza viruses of concern for epidemic spread in humans, though small sample sizes and biological uncertainties prevent definitive classification of human transmissibility. Thus, ferret transmission experiments provide valid predictions of pandemic potential of novel influenza strains, though results should continue to be corroborated by targeted virological and epidemiological research. DOI: http://dx.doi.org/10.7554/eLife.07969.001 PMID:26329460
Cross, Dori A; Boukus, Ellyn R; Cohen, Genna R
2011-01-01
Objective A core feature of e-prescribing is the electronic exchange of prescription data between physician practices and pharmacies, which can potentially improve the efficiency of the prescribing process and reduce medication errors. Barriers to implementing this feature exist, but they are not well understood. This study's objectives were to explore recent physician practice and pharmacy experiences with electronic transmission of new prescriptions and renewals, and identify facilitators of and barriers to effective electronic transmission and pharmacy e-prescription processing. Design Qualitative analysis of 114 telephone interviews conducted with representatives from 97 organizations between February and September 2010, including 24 physician practices, 48 community pharmacies, and three mail-order pharmacies actively transmitting or receiving e-prescriptions via Surescripts. Results Practices and pharmacies generally were satisfied with electronic transmission of new prescriptions but reported that the electronic renewal process was used inconsistently, resulting in inefficient workarounds for both parties. Practice communications with mail-order pharmacies were less likely to be electronic than with community pharmacies because of underlying transmission network and computer system limitations. While e-prescribing reduced manual prescription entry, pharmacy staff frequently had to complete or edit certain fields, particularly drug name and patient instructions. Conclusions Electronic transmission of new prescriptions has matured. Changes in technical standards and system design and more targeted physician and pharmacy training may be needed to address barriers to e-renewals, mail-order pharmacy connectivity, and pharmacy processing of e-prescriptions. PMID:22101907
Selariu, Anca; Powers, Jenny G; Nalls, Amy; Brandhuber, Monica; Mayfield, Amber; Fullaway, Stephenie; Wyckoff, Christy A; Goldmann, Wilfred; Zabel, Mark M; Wild, Margaret A; Hoover, Edward A; Mathiason, Candace K
2015-11-01
The presence of disease-associated prions in tissues and bodily fluids of chronic wasting disease (CWD)-infected cervids has received much investigation, yet little is known about mother-to-offspring transmission of CWD. Our previous work demonstrated that mother-to-offspring transmission is efficient in an experimental setting. To address the question of relevance in a naturally exposed free-ranging population, we assessed maternal and fetal tissues derived from 19 elk dam-calf pairs collected from free-ranging Rocky Mountain elk from north-central Colorado, a known CWD endemic region. Conventional immunohistochemistry identified three of 19 CWD-positive dams, whereas a more sensitive assay [serial protein misfolding cyclic amplification (sPMCA)] detected CWD prion seeding activity (PrPCWD) in 15 of 19 dams. PrPCWD distribution in tissues was widespread, and included the central nervous system (CNS), lymphoreticular system, and reproductive, secretory, excretory and adipose tissues. Interestingly, five of 15 sPMCA-positive dams showed no evidence of PrPCWD in either CNS or lymphoreticular system, sites typically assessed in diagnosing CWD. Analysis of fetal tissues harvested from the 15 sPMCA-positive dams revealed PrPCWD in 80 % of fetuses (12 of 15), regardless of gestational stage. These findings demonstrated that PrPCWD is more abundant in peripheral tissues of CWD-exposed elk than current diagnostic methods suggest, and that transmission of prions from mother to offspring may contribute to the efficient transmission of CWD in naturally exposed cervid populations.
Selariu, Anca; Powers, Jenny G.; Nalls, Amy; Brandhuber, Monica; Mayfield, Amber; Fullaway, Stephenie; Wyckoff, Christy A.; Goldmann, Wilfred; Zabel, Mark M.; Wild, Margaret A.; Hoover, Edward A.
2015-01-01
The presence of disease-associated prions in tissues and bodily fluids of chronic wasting disease (CWD)-infected cervids has received much investigation, yet little is known about mother-to-offspring transmission of CWD. Our previous work demonstrated that mother-to-offspring transmission is efficient in an experimental setting. To address the question of relevance in a naturally exposed free-ranging population, we assessed maternal and fetal tissues derived from 19 elk dam–calf pairs collected from free-ranging Rocky Mountain elk from north-central Colorado, a known CWD endemic region. Conventional immunohistochemistry identified three of 19 CWD-positive dams, whereas a more sensitive assay [serial protein misfolding cyclic amplification (sPMCA)] detected CWD prion seeding activity (PrPCWD) in 15 of 19 dams. PrPCWD distribution in tissues was widespread, and included the central nervous system (CNS), lymphoreticular system, and reproductive, secretory, excretory and adipose tissues. Interestingly, five of 15 sPMCA-positive dams showed no evidence of PrPCWD in either CNS or lymphoreticular system, sites typically assessed in diagnosing CWD. Analysis of fetal tissues harvested from the 15 sPMCA-positive dams revealed PrPCWD in 80 % of fetuses (12 of 15), regardless of gestational stage. These findings demonstrated that PrPCWD is more abundant in peripheral tissues of CWD-exposed elk than current diagnostic methods suggest, and that transmission of prions from mother to offspring may contribute to the efficient transmission of CWD in naturally exposed cervid populations. PMID:26358706
Federal Register 2010, 2011, 2012, 2013, 2014
2013-09-18
... p.m. Requests to speak at one or more public scoping meeting(s) should be received at the address... ADDRESSES section. ADDRESSES: Requests to speak at a public scoping meeting(s), and requests for individuals... Impact Statement: Announcement of Change in Public Meeting Location AGENCY: Department of Energy. ACTION...
The Use of Satellites by Education: Licences, Copyright and Contracts.
ERIC Educational Resources Information Center
Crabb, Geoffrey
This pamphlet is intended to answer questions about copyright with respect to the reception and use of satellite transmissions by educational establishments in the United Kingdom. Addressed to those who receive and record satellite transmissions, Part One discusses both license and copyright requirements, including situations in which permission…
49 CFR 192.933 - What actions must be taken to address integrity issues?
Code of Federal Regulations, 2011 CFR
2011-10-01
... Transmission Pipeline Integrity Management § 192.933 What actions must be taken to address integrity issues? (a... any indication of metal loss, cracking or a stress riser. (iii) An indication or anomaly that in the...
49 CFR 192.933 - What actions must be taken to address integrity issues?
Code of Federal Regulations, 2013 CFR
2013-10-01
... Transmission Pipeline Integrity Management § 192.933 What actions must be taken to address integrity issues? (a... any indication of metal loss, cracking or a stress riser. (iii) An indication or anomaly that in the...
49 CFR 192.933 - What actions must be taken to address integrity issues?
Code of Federal Regulations, 2012 CFR
2012-10-01
... Transmission Pipeline Integrity Management § 192.933 What actions must be taken to address integrity issues? (a... any indication of metal loss, cracking or a stress riser. (iii) An indication or anomaly that in the...
42 CFR 3.106 - Security requirements.
Code of Federal Regulations, 2012 CFR
2012-10-01
..., maintenance, storage, removal, disclosure, transmission and destruction. (b) Security framework. A PSO must... subsection. In addressing the framework that follows, the PSO may develop appropriate and scalable security...) Security management. A PSO must address: (i) Maintenance and effective implementation of written policies...
42 CFR 3.106 - Security requirements.
Code of Federal Regulations, 2013 CFR
2013-10-01
..., maintenance, storage, removal, disclosure, transmission and destruction. (b) Security framework. A PSO must... subsection. In addressing the framework that follows, the PSO may develop appropriate and scalable security...) Security management. A PSO must address: (i) Maintenance and effective implementation of written policies...
42 CFR 3.106 - Security requirements.
Code of Federal Regulations, 2014 CFR
2014-10-01
..., maintenance, storage, removal, disclosure, transmission and destruction. (b) Security framework. A PSO must... subsection. In addressing the framework that follows, the PSO may develop appropriate and scalable security...) Security management. A PSO must address: (i) Maintenance and effective implementation of written policies...
Kalichman, Seth C; Cherry, Chauncey; Kalichman, Moira O; Washington, Christopher; Grebler, Tamar; Hoyt, Ginger; Merely, Cindy; Welles, Brandi
2016-08-01
Antiretroviral therapy (ART) improves the health of people living with HIV and can reduce infectiousness, preventing HIV transmission. The potential preventive benefits of ART are undermined by beliefs that it is safe to have condomless sex when viral load is below levels of detection (infectiousness beliefs and risk perceptions). In this study, we hypothesized that infectiousness beliefs and HIV transmission risk perceptions would prospectively predict people living with HIV engaging in more condomless sex with HIV-negative and unknown HIV status sex partners. Sexually active HIV-positive men (n = 538, 76 %) and women (n = 166, 24 %) completed computerized interviews of sexually transmitted infection (STI) symptoms and diagnoses, unannounced pill counts for medication adherence, medical chart-abstracted HIV viral load, and 28 daily cell-phone-delivered prospective sexual behavior assessments. Results showed that a total of 313 (44 %) participants had engaged in condomless sex with HIV-negative/unknown status sex partners, and these individuals demonstrated higher rates of STI symptoms and diagnoses. Two-thirds of participants who had condomless sex with HIV-negative/unknown status partners had not disclosed their HIV status. Multivariable logistic regression models showed that beliefs regarding viral load and HIV infectiousness and perceptions of lower risk of HIV transmission resulting from HIV viral suppression predicted condomless sex with potentially uninfected partners over and above sex behaviors with HIV-positive partners and STI symptoms/diagnoses. Interventions that address HIV status disclosure and aggressively treat STI in sexually active people living with HIV should routinely accompany the use of HIV treatments as prevention.
Angularly-selective transmission imaging in a scanning electron microscope.
Holm, Jason; Keller, Robert R
2016-08-01
This work presents recent advances in transmission scanning electron microscopy (t-SEM) imaging control capabilities. A modular aperture system and a cantilever-style sample holder that enable comprehensive angular selectivity of forward-scattered electrons are described. When combined with a commercially available solid-state transmission detector having only basic bright-field and dark-field imaging capabilities, the advances described here enable numerous transmission imaging modes. Several examples are provided that demonstrate how contrast arising from diffraction to mass-thickness can be obtained. Unanticipated image contrast at some imaging conditions is also observed and addressed. Published by Elsevier B.V.
Transmission research activities at NASA Lewis Research Center
NASA Technical Reports Server (NTRS)
Lewicki, D. G.
1990-01-01
A joint research program, to advance the technology of rotorcraft transmissions, consists of analytical and experimental efforts to achieve the overall goals of reducing transmission weight and noise, while increasing life and reliability. Recent activities in the areas of transmission and related component research are highlighted. Current areas include specific technologies in support of military rotary wing aviation, gearing technology, transmission noise reduction studies, a recent interest in gearbox diagnostics, and advanced transmission system studies. Results of recent activities are presented along with near term research plans.
Elevation as a proxy for mosquito-borne Zika virus transmission in the Americas.
Watts, Alexander G; Miniota, Jennifer; Joseph, Heather A; Brady, Oliver J; Kraemer, Moritz U G; Grills, Ardath W; Morrison, Stephanie; Esposito, Douglas H; Nicolucci, Adriano; German, Matthew; Creatore, Maria I; Nelson, Bradley; Johansson, Michael A; Brunette, Gary; Hay, Simon I; Khan, Kamran; Cetron, Marty
2017-01-01
When Zika virus (ZIKV) first began its spread from Brazil to other parts of the Americas, national-level travel notices were issued, carrying with them significant economic consequences to affected countries. Although regions of some affected countries were likely unsuitable for mosquito-borne transmission of ZIKV, the absence of high quality, timely surveillance data made it difficult to confidently demarcate infection risk at a sub-national level. In the absence of reliable data on ZIKV activity, a pragmatic approach was needed to identify subnational geographic areas where the risk of ZIKV infection via mosquitoes was expected to be negligible. To address this urgent need, we evaluated elevation as a proxy for mosquito-borne ZIKV transmission. For sixteen countries with local ZIKV transmission in the Americas, we analyzed (i) modelled occurrence of the primary vector for ZIKV, Aedes aegypti, (ii) human population counts, and (iii) reported historical dengue cases, specifically across 100-meter elevation levels between 1,500m and 2,500m. Specifically, we quantified land area, population size, and the number of observed dengue cases above each elevation level to identify a threshold where the predicted risks of encountering Ae. aegypti become negligible. Above 1,600m, less than 1% of each country's total land area was predicted to have Ae. aegypti occurrence. Above 1,900m, less than 1% of each country's resident population lived in areas where Ae. aegypti was predicted to occur. Across all 16 countries, 1.1% of historical dengue cases were reported above 2,000m. These results suggest low potential for mosquito-borne ZIKV transmission above 2,000m in the Americas. Although elevation is a crude predictor of environmental suitability for ZIKV transmission, its constancy made it a pragmatic input for policy decision-making during this public health emergency.
System data communication structures for active-control transport aircraft, volume 1
NASA Technical Reports Server (NTRS)
Hopkins, A. L.; Martin, J. H.; Brock, L. D.; Jansson, D. G.; Serben, S.; Smith, T. B.; Hanley, L. D.
1981-01-01
Candidate data communication techniques are identified, including dedicated links, local buses, broadcast buses, multiplex buses, and mesh networks. The design methodology for mesh networks is then discussed, including network topology and node architecture. Several concepts of power distribution are reviewed, including current limiting and mesh networks for power. The technology issues of packaging, transmission media, and lightning are addressed, and, finally, the analysis tools developed to aid in the communication design process are described. There are special tools to analyze the reliability and connectivity of networks and more general reliability analysis tools for all types of systems.
Mencio, Caitlin; Kuberan, Balagurunathan; Goller, Franz
2017-02-01
Neural control of complex vocal behaviors, such as birdsong and speech, requires integration of biomechanical nonlinearities through muscular output. Although control of airflow and tension of vibrating tissues are known functions of vocal muscles, it remains unclear how specific muscle characteristics contribute to specific acoustic parameters. To address this gap, we removed heparan sulfate chains using heparitinases to perturb neuromuscular transmission subtly in the syrinx of adult male zebra finches (Taeniopygia guttata). Infusion of heparitinases into ventral syringeal muscles altered their excitation threshold and reduced neuromuscular transmission changing their ability to modulate airflow. The changes in muscle activation dynamics caused a reduction in frequency modulation rates and elimination of many high-frequency syllables but did not alter the fundamental frequency of syllables. Sound amplitude was reduced and sound onset pressure was increased, suggesting a role of muscles in the induction of self-sustained oscillations under low-airflow conditions, thus enhancing vocal efficiency. These changes were reversed to preinfusion levels by 7 days after infusion. These results illustrate complex interactions between the control of airflow and tension and further define the importance of syringeal muscle in the control of a variety of acoustic song characteristics. In summary, the findings reported here show that altering neuromuscular transmission can lead to reversible changes to the acoustic structure of song. Understanding the full extent of muscle involvement in song production is critical in decoding the motor program for the production of complex vocal behavior, including our search for parallels between birdsong and human speech motor control. It is largely unknown how fine motor control of acoustic parameters is achieved in vocal organs. Subtle manipulation of syringeal muscle function was used to test how active motor control influences acoustic parameters. Slowed activation kinetics of muscles reduced frequency modulation and, unexpectedly, caused a distinct decrease in sound amplitude and increase in phonation onset pressure. These results show that active control enhances the efficiency of energy conversion in the syrinx. Copyright © 2017 the American Physiological Society.
Faber, Vance; Moore, James W.
1992-01-01
A network of interconnected processors is formed from a vertex symmetric graph selected from graphs .GAMMA..sub.d (k) with degree d, diameter k, and (d+1)!/(d-k+1)! processors for each d.gtoreq.k and .GAMMA..sub.d (k,-1) with degree 3-1, diameter k+1, and (d+1)!/(d-k+1)! processors for each d.gtoreq.k.gtoreq.4. Each processor has an address formed by one of the permutations from a predetermined sequence of letters chosen a selected number of letters at a time, and an extended address formed by appending to the address the remaining ones of the predetermined sequence of letters. A plurality of transmission channels is provided from each of the processors, where each processor has one less channel than the selected number of letters forming the sequence. Where a network .GAMMA..sub.d (k,-1) is provided, no processor has a channel connected to form an edge in a direction .delta..sub.1. Each of the channels has an identification number selected from the sequence of letters and connected from a first processor having a first extended address to a second processor having a second address formed from a second extended address defined by moving to the front of the first extended address the letter found in the position within the first extended address defined by the channel identification number. The second address is then formed by selecting the first elements of the second extended address corresponding to the selected number used to form the address permutations.
Addressable Inverter Matrix Tests Integrated-Circuit Wafer
NASA Technical Reports Server (NTRS)
Buehler, Martin G.
1988-01-01
Addressing elements indirectly through shift register reduces number of test probes. With aid of new technique, complex test structure on silicon wafer tested with relatively small number of test probes. Conserves silicon area by reduction of area devoted to pads. Allows thorough evaluation of test structure characteristics and of manufacturing process parameters. Test structure consists of shift register and matrix of inverter/transmission-gate cells connected to two-by-ten array of probe pads. Entire pattern contained in square area having only 1.6-millimeter sides. Shift register is conventional static CMOS device using inverters and transmission gates in master/slave D flip-flop configuration.
49 CFR 192.933 - What actions must be taken to address integrity issues?
Code of Federal Regulations, 2010 CFR
2010-10-01
...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Transmission Pipeline Integrity Management § 192.933 What actions must be taken to address integrity issues? (a...
Dust storms and their impact on ocean and human health: dust in Earth's atmosphere
Griffin, Dale W.; Kellog, Christina A.
2004-01-01
Satellite imagery has greatly influenced our understanding of dust activity on a global scale. A number of different satellites such as NASA's Earth-Probe Total Ozone Mapping Spectrometer (TOMS) and Se-viewing Field-of-view Sensor (SeaWiFS) acquire daily global-scale data used to produce imagery for monitoring dust storm formation and movement. This global-scale imagery has documented the frequent transmission of dust storm-derived soils through Earth's atmosphere and the magnitude of many of these events. While various research projects have been undertaken to understand this normal planetary process, little has been done to address its impact on ocean and human health. This review will address the ability of dust storms to influence marine microbial population densities and transport of soil-associated toxins and pathogenic microorganisms to marine environments. The implications of dust on ocean and human health in this emerging scientific field will be discussed.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-17
.... Transmission Line EIS, contact Brian Mills as indicated in the ADDRESSES section above. For general information... Executive Order (E.O.) 10485 (September 9, 1953), as amended by E.O. 12038 (February 7, 1978), requires that... California State Historic Preservation Officer (SHPO) regarding potential impacts on historic properties, as...
B. W. Butler; J. Webb; J. Hogge; T. Wallace
2015-01-01
Towers and poles supporting power transmission and telecommunication lines have collapsed due to heating from wildland fires. Such occurrences have led to interruptions in power or communication in large municipal areas with associated social and political implications as well as increased immediate danger to humans. Unfortunately, no studies address the question of...
77 FR 74658 - Texas Eastern Transmission, LP; Notice of Technical Conference
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-17
...-captioned proceeding \\1\\ directed that a technical conference be held to address issues raised by Texas... adjustments. \\1\\ Texas Eastern Transmission, LP, 141 FERC ]61,172 (2012). Take notice that a technical conference will be held on Tuesday, January 15, 2013 at 9:30 a.m., in a room to be designated at the offices...
Hughes, Anne K; Alford, Kristen R
2017-01-02
HIV infection among older adults is increasing. Previous research suggests that many older adults do not see themselves as at risk for HIV and that many subscribe to myths related to HIV transmission. In this focus group study (N = 48) we solicited the beliefs that older adults held about HIV. The older adults in this study were knowledgeable about how HIV is typically transmitted. However, we also identified that they subscribed to misconceptions regarding casual contact transmission and were fearful of transmission from the medical system. Educational efforts aimed at older adults must be tailored to address these persistent misconceptions.
Event generators for address event representation transmitters
NASA Astrophysics Data System (ADS)
Serrano-Gotarredona, Rafael; Serrano-Gotarredona, Teresa; Linares Barranco, Bernabe
2005-06-01
Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows for real-time virtual massive connectivity between huge number neurons located on different chips. By exploiting high speed digital communication circuits (with nano-seconds timings), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Also, neurons generate 'events' according to their activity levels. More active neurons generate more events per unit time, and access the interchip communication channel more frequently, while neurons with low activity consume less communication bandwidth. In a typical AER transmitter chip, there is an array of neurons that generate events. They send events to a peripheral circuitry (let's call it "AER Generator") that transforms those events to neurons coordinates (addresses) which are put sequentially on an interchip high speed digital bus. This bus includes a parallel multi-bit address word plus a Rqst (request) and Ack (acknowledge) handshaking signals for asynchronous data exchange. There have been two main approaches published in the literature for implementing such "AER Generator" circuits. They differ on the way of handling event collisions coming from the array of neurons. One approach is based on detecting and discarding collisions, while the other incorporates arbitration for sequencing colliding events . The first approach is supposed to be simpler and faster, while the second is able to handle much higher event traffic. In this article we will concentrate on the second arbiter-based approach. Boahen has been publishing several techniques for implementing and improving the arbiter based approach. Originally, he proposed an arbitration squeme by rows, followed by a column arbitration. In this scheme, while one neuron was selected by the arbiters to transmit his event out of the chip, the rest of neurons in the array were freezed to transmit any further events during this time window. This limited the maximum transmission speed. In order to improve this speed, Boahen proposed an improved 'burst mode' scheme. In this scheme after the row arbitration, a complete row of events is pipelined out of the array and arbitered out of the chip at higher speed. During this single row event arbitration, the array is free to generate new events and communicate to the row arbiter, in a pipelined mode. This scheme significantly improves maximum event transmission speed, specially for high traffic situations were speed is more critical. We have analyzed and studied this approach and have detected some shortcomings in the circuits reported by Boahen, which may render some false situations under some statistical conditions. The present paper proposes some improvements to overcome such situations. The improved "AER Generator" has been implemented in an AER transmitter system
10 CFR 1016.33 - External transmission of documents and material.
Code of Federal Regulations, 2014 CFR
2014-01-01
... ordinary manner and sealed with tape, the appropriate classification shall be placed on both sides of the... address. (3) The outer envelope or wrapper shall be addressed in the ordinary manner. No classification... clearance or access authorization who have been given written authority by their employers. (2) Confidential...
10 CFR 1016.33 - External transmission of documents and material.
Code of Federal Regulations, 2012 CFR
2012-01-01
... ordinary manner and sealed with tape, the appropriate classification shall be placed on both sides of the... address. (3) The outer envelope or wrapper shall be addressed in the ordinary manner. No classification... clearance or access authorization who have been given written authority by their employers. (2) Confidential...
NASA Technical Reports Server (NTRS)
Oliver, D. S.; Aldrich, R. E.; Krol, F. T.
1972-01-01
An electrically addressed liquid crystal Fourier plane filter capable of real time optical image processing is described. The filter consists of two parts: a wedge filter having forty 9 deg segments and a ring filter having twenty concentric rings in a one inch diameter active area. Transmission of the filter in the off (transparent) state exceeds fifty percent. By using polarizing optics, contrast as high as 10,000:1 can be achieved at voltages compatible with FET switching technology. A phenomenological model for the dynamic scattering is presented for this special case. The filter is designed to be operated from a computer and is addressed by a seven bit binary word which includes an on or off command and selects any one of the twenty rings or twenty wedge pairs. The overall system uses addressable latches so that once an element is in a specified state, it will remain there until a change of state command is received. The drive for the liquid crystal filter is ? 30 V peak at 30 Hz to 70 Hz. These parameters give a rise time for the scattering of 20 msec and a decay time of 80 to 100 msec.
For telehealth to succeed, privacy and security risks must be identified and addressed.
Hall, Joseph L; McGraw, Deven
2014-02-01
The success of telehealth could be undermined if serious privacy and security risks are not addressed. For example, sensors that are located in a patient's home or that interface with the patient's body to detect safety issues or medical emergencies may inadvertently transmit sensitive information about household activities. Similarly, routine data transmissions from an app or medical device, such as an insulin pump, may be shared with third-party advertisers. Without adequate security and privacy protections for underlying telehealth data and systems, providers and patients will lack trust in the use of telehealth solutions. Although some federal and state guidelines for telehealth security and privacy have been established, many gaps remain. No federal agency currently has authority to enact privacy and security requirements to cover the telehealth ecosystem. This article examines privacy risks and security threats to telehealth applications and summarizes the extent to which technical controls and federal law adequately address these risks. We argue for a comprehensive federal regulatory framework for telehealth, developed and enforced by a single federal entity, the Federal Trade Commission, to bolster trust and fully realize the benefits of telehealth.
The evolution of plant virus transmission pathways.
Hamelin, Frédéric M; Allen, Linda J S; Prendeville, Holly R; Hajimorad, M Reza; Jeger, Michael J
2016-05-07
The evolution of plant virus transmission pathways is studied through transmission via seed, pollen, or a vector. We address the questions: under what circumstances does vector transmission make pollen transmission redundant? Can evolution lead to the coexistence of multiple virus transmission pathways? We restrict the analysis to an annual plant population in which reproduction through seed is obligatory. A semi-discrete model with pollen, seed, and vector transmission is formulated to investigate these questions. We assume vector and pollen transmission rates are frequency-dependent and density-dependent, respectively. An ecological stability analysis is performed for the semi-discrete model and used to inform an evolutionary study of trade-offs between pollen and seed versus vector transmission. Evolutionary dynamics critically depend on the shape of the trade-off functions. Assuming a trade-off between pollen and vector transmission, evolution either leads to an evolutionarily stable mix of pollen and vector transmission (concave trade-off) or there is evolutionary bi-stability (convex trade-off); the presence of pollen transmission may prevent evolution of vector transmission. Considering a trade-off between seed and vector transmission, evolutionary branching and the subsequent coexistence of pollen-borne and vector-borne strains is possible. This study contributes to the theory behind the diversity of plant-virus transmission patterns observed in nature. Copyright © 2016 Elsevier Ltd. All rights reserved.
Interrupting poliovirus transmission -- new solutions to an old problem.
Aylward, R Bruce; Maher, Chris
2006-06-01
Since the launch of the Global Polio Eradication Initiative (GPEI) in 1988, knowledge as to the nature of circulating polioviruses and the challenges to their interruption has increased tremendously, particularly during the period 2000-2005. By January 2006, however, the systematic application of the standard polio eradication strategies, combined with recent refinements, had reduced the number of countries with ongoing transmission of indigenous wild polioviruses to just four (Nigeria, India, Pakistan, and Afghanistan), the lowest ever in history. In addition, only 8 of the 22 areas that had been re-infected by wild poliovirus in 2003-2005 still required large-scale 'mop-up' activities and circulating vaccine-derived poliovirus (cVDPV) outbreaks were being readily addressed. This progress, despite new challenges late in the GPEI, was greatly facilitated by a range of solutions that included two new monovalent oral polio vaccines (mOPVs), new and robust international standards for polio outbreak response, and renewed political commitment across the remaining infected countries.
HIV/AIDS in eastern Europe: more than a sexual health crisis.
Lazarus, Jeffrey V; Bollerup, Annemarie; Matić, Srdan
2006-06-01
HIV/AIDS is often described as a sexually transmitted disease. In the former USSR, however, the HIV/AIDS epidemic is being driven by injecting drug use among men. This article addresses several widely circulated assumptions about HIV in eastern Europe: that sexual contact is the primary mode of transmission, that women form a major increasing proportion of those infected, and that the disease threatens young people in particular. Because the rate of injecting drug use is extremely high in many eastern European countries, HIV control there cannot just target sexual transmission but must embrace other approaches, such as comprehensive harm reduction. In the area of treatment, scaling up access to highly active antiretroviral therapy has been a major global priority for the last two years. European efforts to broaden access have been generally quite successful, yet in the two European countries with the greatest need, the Russian Federation and Ukraine, the demand for treatment is growing much faster than its availability.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The Western Area Power Administration (Western) has established a formal environmental protection, auditing, monitoring, and planning program that has been in effect since 1978. The significant environmental projects and issues Western was involved with in 1995 are discussed in this annual site environmental report. It is written to show the nature and effectiveness of the environmental protection program. Western operates and maintains nearly 17,000 miles of transmission lines, 257 substations, and various appurtenant power facilities in fifteen central and western states. Western is also responsible for planning, construction, and operation and maintenance of additional federal transmission facilities that may bemore » authorized in the future. There is a combined total of 55 hydroelectric power generating plants in the service area. Additionally, Western markets the US entitlement from the Navajo coal-fired plant near Page, Arizona. The Department of Energy requires the preparation of an annual site environmental report. Because Western has over 400 facilities located in these states, this report addresses the environmental activities in all the facilities as one site.« less
Organizing Asian Pacific Islanders in an urban community to reduce HIV risk: a case study.
Loue, S; Lloyd, L S; Phoombour, E
1996-10-01
We present a case study of community organization efforts within the Asian Pacific Islander communities of San Diego County to reduce the risk of HIV transmission. We utilized a five-phase process to implement the strategies of locality development, social planning, and social action: community analysis, program design and initiation, program implementation, program maintenance and consolidation, and program reassessment. An evaluation of the process indicates that there were increases over time in the project's activities as well as in the levels of interagency connectedness. This is one of the few reported efforts to organize Asian Pacific Islander groups to address HIV transmission. Key elements that led to the successful organization of the original project into a tax-exempt nonprofit entity (the Asian Pacific Islander Community AIDS Project) were emphasis on community ownership, reliance on group consensus, use of "gatekeepers" to access communities, simultaneous multilevel programming, and service to the community as a "coordinating" entity.
Alkhasawneh, Esra; McFarland, Willi; Mandel, Jeffery; Seshan, Vidya
2014-01-01
Research on HIV prevention programs for countries with large Muslim populations is scarce. HIV knowledge, attitudes, and beliefs were assessed in a convenience sample of 128 women and 88 men at two universities in Jordan with the goal of gaining insight into how to approach HIV risk behaviors. In general terms, 97% of participants had heard of AIDS and the majority understood the common methods of transmission. Misconceptions were common; most participants did not recognize condoms as an HIV prevention method. A sense of fatalism regarding the acquisition of HIV was common. In Jordan, challenges to HIV-prevention interventions includes misconceptions about HIV transmission, gender-related differences in the willingness to discuss sexual issues, and fatalism regarding the acquisition of HIV. Silence about sexual activity, particularly among women, was pervasive. Culturally tailored interventions are needed to decrease stigma and address gender inequalities that may contribute to increased risks of HIV in Jordan. Copyright © 2014 Association of Nurses in AIDS Care. All rights reserved.
Zhang, Mingming; Ladas, Thomas P.; Qiu, Chen; Shivacharan, Rajat S.; Gonzalez-Reyes, Luis E.
2014-01-01
The propagation of activity in neural tissue is generally associated with synaptic transmission, but epileptiform activity in the hippocampus can propagate with or without synaptic transmission at a speed of ∼0.1 m/s. This suggests an underlying common nonsynaptic mechanism for propagation. To study this mechanism, we developed a novel unfolded hippocampus preparation, from CD1 mice of either sex, which preserves the transverse and longitudinal connections and recorded activity with a penetrating microelectrode array. Experiments using synaptic transmission and gap junction blockers indicated that longitudinal propagation is independent of chemical or electrical synaptic transmission. Propagation speeds of 0.1 m/s are not compatible with ionic diffusion or pure axonal conduction. The only other means of communication between neurons is through electric fields. Computer simulations revealed that activity can indeed propagate from cell to cell solely through field effects. These results point to an unexpected propagation mechanism for neural activity in the hippocampus involving endogenous field effect transmission. PMID:24453330
Towards tuberculosis elimination: an action framework for low-incidence countries
Lönnroth, Knut; Migliori, Giovanni Battista; Abubakar, Ibrahim; D'Ambrosio, Lia; de Vries, Gerard; Diel, Roland; Douglas, Paul; Falzon, Dennis; Gaudreau, Marc-Andre; Goletti, Delia; González Ochoa, Edilberto R.; LoBue, Philip; Matteelli, Alberto; Njoo, Howard; Solovic, Ivan; Story, Alistair; Tayeb, Tamara; van der Werf, Marieke J.; Weil, Diana; Zellweger, Jean-Pierre; Abdel Aziz, Mohamed; Al Lawati, Mohamed R.M.; Aliberti, Stefano; Arrazola de Oñate, Wouter; Barreira, Draurio; Bhatia, Vineet; Blasi, Francesco; Bloom, Amy; Bruchfeld, Judith; Castelli, Francesco; Centis, Rosella; Chemtob, Daniel; Cirillo, Daniela M.; Colorado, Alberto; Dadu, Andrei; Dahle, Ulf R.; De Paoli, Laura; Dias, Hannah M.; Duarte, Raquel; Fattorini, Lanfranco; Gaga, Mina; Getahun, Haileyesus; Glaziou, Philippe; Goguadze, Lasha; del Granado, Mirtha; Haas, Walter; Järvinen, Asko; Kwon, Geun-Yong; Mosca, Davide; Nahid, Payam; Nishikiori, Nobuyuki; Noguer, Isabel; O'Donnell, Joan; Pace-Asciak, Analita; Pompa, Maria G.; Popescu, Gilda G.; Robalo Cordeiro, Carlos; Rønning, Karin; Ruhwald, Morten; Sculier, Jean-Paul; Simunović, Aleksandar; Smith-Palmer, Alison; Sotgiu, Giovanni; Sulis, Giorgia; Torres-Duque, Carlos A.; Umeki, Kazunori; Uplekar, Mukund; van Weezenbeek, Catharina; Vasankari, Tuula; Vitillo, Robert J.; Voniatis, Constantia; Wanlin, Maryse; Raviglione, Mario C.
2015-01-01
This paper describes an action framework for countries with low tuberculosis (TB) incidence (<100 TB cases per million population) that are striving for TB elimination. The framework sets out priority interventions required for these countries to progress first towards “pre-elimination” (<10 cases per million) and eventually the elimination of TB as a public health problem (less than one case per million). TB epidemiology in most low-incidence countries is characterised by a low rate of transmission in the general population, occasional outbreaks, a majority of TB cases generated from progression of latent TB infection (LTBI) rather than local transmission, concentration to certain vulnerable and hard-to-reach risk groups, and challenges posed by cross-border migration. Common health system challenges are that political commitment, funding, clinical expertise and general awareness of TB diminishes as TB incidence falls. The framework presents a tailored response to these challenges, grouped into eight priority action areas: 1) ensure political commitment, funding and stewardship for planning and essential services; 2) address the most vulnerable and hard-to-reach groups; 3) address special needs of migrants and cross-border issues; 4) undertake screening for active TB and LTBI in TB contacts and selected high-risk groups, and provide appropriate treatment; 5) optimise the prevention and care of drug-resistant TB; 6) ensure continued surveillance, programme monitoring and evaluation and case-based data management; 7) invest in research and new tools; and 8) support global TB prevention, care and control. The overall approach needs to be multisectorial, focusing on equitable access to high-quality diagnosis and care, and on addressing the social determinants of TB. Because of increasing globalisation and population mobility, the response needs to have both national and global dimensions. PMID:25792630
ERIC Educational Resources Information Center
Powdthavee, Nattavudh; Vignoles, Anna
2008-01-01
This paper addresses the extent to which there is an intergenerational transmission of mental health and subjective well-being within families. Specifically it asks whether parents' own mental distress influences their child's life satisfaction, and vice versa. Whilst the evidence on daily contagion of stress and strain between members of the same…
Bandwidth Management in Resource Constrained Networks
2012-03-01
Postgraduate School OSI Open Systems Interconnection QoS Quality of Service TCP Transmission Control Protocol/Internet Protocol TCP/IP Transmission...filtering. B. NORMAL TCP/IP COMMUNICATIONS The Internet is a “complex network WAN that connects LANs and clients around the globe” (Dean, 2009...of the Open Systems Interconnection ( OSI ) model allowing them to route traffic based on MAC address (Kurose & Ross, 2009). While switching
ERIC Educational Resources Information Center
Gniewosz, Burkhard; Noack, Peter
2012-01-01
The present research addresses processes involved in academic value transmission within family. Drawing on expectancy x value and social learning theory, a two-wave longitudinal study based on data from 1014 students, 878 mothers, and 748 fathers was conducted to examine the mechanisms of parental influence. Structural equation modeling provided…
ERIC Educational Resources Information Center
Gasiorowicz, Mari; Llanas, Michelle R.; DiFranceisco, Wayne; Benotsch, Eric G.; Brondino, Michael J.; Catz, Sheryl L.; Hoxie, Neil J.; Reiser, William J.; Vergeront, James M.
2005-01-01
Prevention case management (PCM) for HIV-infected persons is an HIV risk reduction intervention designed to assist clients who are aware of their HIV infection and who continue to engage in risk transmission behaviors. PCM combines individual risk reduction counseling with case management to address the psychosocial factors affecting HIV…
Striatal dopamine neurotransmission: regulation of release and uptake
Sulzer, David; Cragg, Stephanie J.; Rice, Margaret E.
2016-01-01
Dopamine (DA) transmission is governed by processes that regulate release from axonal boutons in the forebrain and the somatodendritic compartment in midbrain, and by clearance by the DA transporter, diffusion, and extracellular metabolism. We review how axonal DA release is regulated by neuronal activity and by autoreceptors and heteroreceptors, and address how quantal release events are regulated in size and frequency. In brain regions densely innervated by DA axons, DA clearance is due predominantly to uptake by the DA transporter, whereas in cortex, midbrain, and other regions with relatively sparse DA inputs, the norepinephrine transporter and diffusion are involved. We discuss the role of DA uptake in restricting the sphere of influence of DA and in temporal accumulation of extracellular DA levels upon successive action potentials. The tonic discharge activity of DA neurons may be translated into a tonic extracellular DA level, whereas their bursting activity can generate discrete extracellular DA transients. PMID:27141430
NASA Technical Reports Server (NTRS)
Forbes, Kevin F.; Cyr, Chris St
2012-01-01
During solar cycle 22, a very intense geomagnetic storm on 13 March 1989 contributed to the collapse of the Hydro-Quebec power system in Canada. This event clearly demonstrated that geomagnetic storms have the potential to lead to blackouts. This paper addresses whether geomagnetic activity challenged power system reliability during solar cycle 23. Operations by PJM Interconnection, LLC (hereafter PJM), a regional transmission organization in North America, are examined over the period 1 April 2002 through 30 April 2004. During this time PJM coordinated the movement of wholesale electricity in all or parts of Delaware, Maryland, New Jersey, Ohio, Pennsylvania, Virginia, West Virginia, and the District of Columbia in the United States. We examine the relationship between a proxy of geomagnetically induced currents (GICs) and a metric of challenged reliability. In this study, GICs are proxied using magnetometer data from a geomagnetic observatory located just outside the PJM control area. The metric of challenged reliability is the incidence of out-of-economic-merit order dispatching due to adverse reactive power conditions. The statistical methods employed make it possible to disentangle the effects of GICs on power system operations from purely terrestrial factors. The results of the analysis indicate that geomagnetic activity can significantly increase the likelihood that the system operator will dispatch generating units based on system stability considerations rather than economic merit.
Cost estimation of HVDC transmission system of Bangka's NPP candidates
NASA Astrophysics Data System (ADS)
Liun, Edwaren; Suparman
2014-09-01
Regarding nuclear power plant development in Bangka Island, it can be estimated that produced power will be oversupply for the Bangka Island and needs to transmit to Sumatra or Java Island. The distance between the regions or islands causing considerable loss of power in transmission by alternating current, and a wide range of technical and economical issues. The objective of this paper addresses to economics analysis of direct current transmission system to overcome those technical problem. Direct current transmission has a stable characteristic, so that the power delivery from Bangka to Sumatra or Java in a large scale efficiently and reliably can be done. HVDC system costs depend on the power capacity applied to the system and length of the transmission line in addition to other variables that may be different.
Kheifets, Leeka; Crespi, Catherine M; Hooper, Chris; Oksuzyan, Sona; Cockburn, Myles; Ly, Thomas; Mezei, Gabor
2015-01-01
We conducted a large epidemiologic case-control study in California to examine the association between childhood cancer risk and distance from the home address at birth to the nearest high-voltage overhead transmission line as a replication of the study of Draper et al. in the United Kingdom. We present a detailed description of the study design, methods of case ascertainment, control selection, exposure assessment and data analysis plan. A total of 5788 childhood leukemia cases and 3308 childhood central nervous system cancer cases (included for comparison) and matched controls were available for analysis. Birth and diagnosis addresses of cases and birth addresses of controls were geocoded. Distance from the home to nearby overhead transmission lines was ascertained on the basis of the electric power companies’ geographic information system (GIS) databases, additional Google Earth aerial evaluation and site visits to selected residences. We evaluated distances to power lines up to 2000 m and included consideration of lower voltages (60–69 kV). Distance measures based on GIS and Google Earth evaluation showed close agreement (Pearson correlation >0.99). Our three-tiered approach to exposure assessment allowed us to achieve high specificity, which is crucial for studies of rare diseases with low exposure prevalence. PMID:24045429
Majumdar, Angshul; Gogna, Anupriya; Ward, Rabab
2014-08-25
We address the problem of acquiring and transmitting EEG signals in Wireless Body Area Networks (WBAN) in an energy efficient fashion. In WBANs, the energy is consumed by three operations: sensing (sampling), processing and transmission. Previous studies only addressed the problem of reducing the transmission energy. For the first time, in this work, we propose a technique to reduce sensing and processing energy as well: this is achieved by randomly under-sampling the EEG signal. We depart from previous Compressed Sensing based approaches and formulate signal recovery (from under-sampled measurements) as a matrix completion problem. A new algorithm to solve the matrix completion problem is derived here. We test our proposed method and find that the reconstruction accuracy of our method is significantly better than state-of-the-art techniques; and we achieve this while saving sensing, processing and transmission energy. Simple power analysis shows that our proposed methodology consumes considerably less power compared to previous CS based techniques.
Antiretroviral Therapy for the Prevention of HIV Transmission: What Will It Take?
McNairy, Margaret L.; El-Sadr, Wafaa M.
2014-01-01
The evidence in support of use of antiretroviral therapy (ART) for prevention of human immunodeficiency virus (HIV) transmission is encouraging and has stimulated optimism for achieving a dramatic change in the trajectory of the HIV epidemic. Yet, there are substantial challenges that, if not addressed, could be the Achilles’ heel for this concept. These challenges require strengthening every step of the HIV care continuum, including expansion of HIV testing to reach all those with HIV infection, effective linkage to and retention in care, timely initiation of ART, and high levels of treatment adherence with viral load suppression. Also important is the identification of individuals with acute HIV infection whose contribution to HIV transmission may be substantial. Implementation research is needed to identify strategies that address these challenges and to determine the efficacy of ART for prevention in key populations as well as to evaluate the effectiveness of combination strategies for HIV prevention at the population level. PMID:24429438
The ketogenic diet: metabolic influences on brain excitability and epilepsy
Lutas, Andrew; Yellen, Gary
2012-01-01
A dietary therapy for pediatric epilepsy known as the ketogenic diet has seen a revival in its clinical use in the past decade. Though the diet’s underlying mechanism remains unknown, modern scientific approaches like genetic disruption of glucose metabolism are allowing for more detailed questions to be addressed. Recent work indicates that several mechanisms may exist for the ketogenic diet including disruption of glutamatergic synaptic transmission, inhibition of glycolysis, and activation of ATP-sensitive potassium channels. Here we describe on-going work in these areas that is providing a better understanding of metabolic influences on brain excitability and epilepsy. PMID:23228828
Performance assessment of small-package-class nonintrusive inspection systems
NASA Astrophysics Data System (ADS)
Spradling, Michael L.; Hyatt, Roger
1997-02-01
The DoD Counterdrug Technology Development Program has addressed the development and demonstration of technology to enhance nonintrusive inspection of small packages such as passenger baggage, commercially delivered parcels, and breakbulk cargo items. Within the past year they have supported several small package-class nonintrusive inspection system performance assessment activities. All performance assessment programs involved the use of a red/blue team concept and were conducted in accordance with approved assessment protocols. This paper presents a discussion related to the systematic performance assessment of small package-class nonintrusive inspection technologies, including transmission, backscatter and computed tomography x-ray imaging, and protocol-related considerations for the assessment of these systems.
The importance of addressing gender inequality in efforts to end vertical transmission of HIV.
Ghanotakis, Elena; Peacock, Dean; Wilcher, Rose
2012-07-11
The recently launched "Global Plan towards the Elimination of New HIV Infections among Children by 2015 and Keeping their Mothers Alive" sets forth ambitious targets that will require more widespread implementation of comprehensive prevention of vertical HIV transmission (PMTCT) programmes. As PMTCT policymakers and implementers work toward these new goals, increased attention must be paid to the role that gender inequality plays in limiting PMTCT programmatic progress. A growing body of evidence suggests that gender inequality, including gender-based violence, is a key obstacle to better outcomes related to all four components of a comprehensive PMTCT programme. Gender inequality affects the ability of women and girls to protect themselves from HIV, prevent unintended pregnancies and access and continue to use HIV prevention, care and treatment services. In light of this evidence, global health donors and international bodies increasingly recognize that it is critical to address the gender disparities that put women and children at increased risk of HIV and impede their access to care. The current policy environment provides unprecedented opportunities for PMTCT implementers to integrate efforts to address gender inequality with efforts to expand access to clinical interventions for preventing vertical HIV transmission. Effective community- and facility-based strategies to transform harmful gender norms and mitigate the impacts of gender inequality on HIV-related outcomes are emerging. PMTCT programmes must embrace these strategies and expand beyond the traditional focus of delivering ARV prophylaxis to pregnant women living with HIV. Without greater implementation of comprehensive, gender transformative PMTCT programmes, elimination of vertical transmission of HIV will remain elusive.
The importance of addressing gender inequality in efforts to end vertical transmission of HIV
Ghanotakis, Elena; Peacock, Dean; Wilcher, Rose
2012-01-01
Issues The recently launched “Global Plan towards the Elimination of New HIV Infections among Children by 2015 and Keeping their Mothers Alive” sets forth ambitious targets that will require more widespread implementation of comprehensive prevention of vertical HIV transmission (PMTCT) programmes. As PMTCT policymakers and implementers work toward these new goals, increased attention must be paid to the role that gender inequality plays in limiting PMTCT programmatic progress. Description A growing body of evidence suggests that gender inequality, including gender-based violence, is a key obstacle to better outcomes related to all four components of a comprehensive PMTCT programme. Gender inequality affects the ability of women and girls to protect themselves from HIV, prevent unintended pregnancies and access and continue to use HIV prevention, care and treatment services. Lessons Learned In light of this evidence, global health donors and international bodies increasingly recognize that it is critical to address the gender disparities that put women and children at increased risk of HIV and impede their access to care. The current policy environment provides unprecedented opportunities for PMTCT implementers to integrate efforts to address gender inequality with efforts to expand access to clinical interventions for preventing vertical HIV transmission. Effective community- and facility-based strategies to transform harmful gender norms and mitigate the impacts of gender inequality on HIV-related outcomes are emerging. PMTCT programmes must embrace these strategies and expand beyond the traditional focus of delivering ARV prophylaxis to pregnant women living with HIV. Without greater implementation of comprehensive, gender transformative PMTCT programmes, elimination of vertical transmission of HIV will remain elusive. PMID:22789642
Insights About Head Lice Transmission From Field Data and Mathematical Modeling.
Toloza, Ariel Ceferino; Laguna María, Fabiana; Ortega-Insaurralde, Isabel; Vassena, Claudia; Risau-Gusman, Sebastián
2018-02-22
Head lice infest millions of school-age children every year, both in developed and developing countries. However, little is known about the number of lice transferred among children during school activities, because direct methods to study this are almost impossible to implement. This issue has been addressed following an indirect method, which consist in collecting data of real infestation from several children groups and using a mathematical model of lice colonies to infer how the infestation observed might have evolved. By determining the events that would most likely lead to infestations as those observed, we find that severe infestations are most likely initiated by a relatively large number of lice transferred at the same moment or within relatively short time spans. In turn, analysis of the data obtained from screenings of the same groups of children a few days apart shows evidence of such transmission events. Interestingly, only children with severe infestations could harbor the lice necessary for this type of transmission. Thus, they play the same role as 'superspreaders' in epidemiology. As part of our experimental study it is also shown that a simple procedure of combing can be very effective to remove all mobile lice, and thus could be used as an effective preventive measure against those severe infestations that are responsible for the spread of pediculosis.
Survivable architectures for time and wavelength division multiplexed passive optical networks
NASA Astrophysics Data System (ADS)
Wong, Elaine
2014-08-01
The increased network reach and customer base of next-generation time and wavelength division multiplexed PON (TWDM-PONs) have necessitated rapid fault detection and subsequent restoration of services to its users. However, direct application of existing solutions for conventional PONs to TWDM-PONs is unsuitable as these schemes rely on the loss of signal (LOS) of upstream transmissions to trigger protection switching. As TWDM-PONs are required to potentially use sleep/doze mode optical network units (ONU), the loss of upstream transmission from a sleeping or dozing ONU could erroneously trigger protection switching. Further, TWDM-PONs require its monitoring modules for fiber/device fault detection to be more sensitive than those typically deployed in conventional PONs. To address the above issues, three survivable architectures that are compliant with TWDM-PON specifications are presented in this work. These architectures combine rapid detection and protection switching against multipoint failure, and most importantly do not rely on upstream transmissions for LOS activation. Survivability analyses as well as evaluations of the additional costs incurred to achieve survivability are performed and compared to the unprotected TWDM-PON. Network parameters that impact the maximum achievable network reach, maximum split ratio, connection availability, fault impact, and the incremental reliability costs for each proposed survivable architecture are highlighted.
1994-05-20
Although previous recommendations for preventing transmission of human immunodeficiency virus (HIV) through transplantation of human tissue and organs have markedly reduced the risk for this type of transmission, a case of HIV transmission from a screened, antibody-negative donor to several recipients raised questions about the need for additional federal oversight of transplantation of organs and tissues. A working group formed by the Public Health Service (PHS) in 1991 to address these issues concluded that further recommendations should be made to reduce the already low risk of HIV transmission by transplantation of organs and tissues. In revising these recommendations, the PHS sought assistance from public and private health professionals and representatives of transplant, public health, and other organizations. The revised guidelines address issues such as donor screening, testing, and exclusionary criteria; quarantine of tissue from living donors; inactivation or elimination of infectious organisms in organs and tissues before transplantation; timely detection, reporting, and tracking of potentially infected tissues, organs, and recipients; and recall of stored tissues from donors found after donation to have been infected. Factors considered in the development of these guidelines include differences between the screening of living and cadaveric donors; time constraints due to organ/tissue viability that may preclude performing certain screening procedures; differences in the risk of HIV transmission from various organs and tissues; differences between systems for procuring and distributing organs and tissues; the effect of screening practices on the limited availability of organs and some tissues; and the benefit of the transplant to the recipient.
Assessment of Antibodies Induced by Multivalent Transmission-Blocking Malaria Vaccines.
Menon, Vinay; Kapulu, Melissa C; Taylor, Iona; Jewell, Kerry; Li, Yuanyuan; Hill, Fergal; Long, Carole A; Miura, Kazutoyo; Biswas, Sumi
2017-01-01
A malaria transmission-blocking vaccine would be a critical tool in achieving malaria elimination and eradication. By using chimpanzee adenovirus serotype 63 and modified vaccinia virus Ankara viral vectored vaccines, we investigated whether incorporating two antigens into one vaccine would result in higher transmission-reducing activity than one antigen. We demonstrated that when Pfs25 was administered with other antigens Pfs28 or Pfs230C, either concurrently as a mixed vaccine or co-expressed as a dual-antigen vaccine, the antibody response in mice to each antigen was comparable to a monoantigen vaccine, without immunological interference. However, we found that the transmission-reducing activity (functional activity) of dual-antigen vaccines was not additive. Dual-antigen vaccines generally only elicited similar transmission-reducing activity to monoantigen vaccines and in one instance had lower transmission-reducing activity. We found that despite the lack of immunological interference of dual-antigen vaccines, they are still not as effective at blocking malaria transmission as Pfs25-IMX313, the current leading candidate for viral vectored vaccines. Pfs25-IMX313 elicited similar quality antibodies to dual-antigen vaccines, but higher antibody titers.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-27
... prepared by the FERC entitled ``An Interstate Natural Gas Facility on My Land? What Do I Need To Know?'' is available for viewing on the FERC Web site ( http://www.ferc.gov ). This fact sheet addresses a number of... metering and regulating (M&R) station in the Borough of Staten Island, New York; Construction of...
International Symposium on Electromagnetic Compatibility, Wakefield, MA, August 20-22, 1985, Record
NASA Astrophysics Data System (ADS)
Various papers on electromagnetic compatibility are presented. The general topics addressed include: EMI transient/impulsive disturbances, electromagnetic shielding, antennas and propagation, measurement technology, anechoic chamber/open site measurements, communications systems, electrostatic discahrge, cables/transmission lines. Also considered are: elecromagnetic environments, antennas, electromagnetic pulse, nonlinear effect, computer/data transmission systems, EMI standards and requirements, enclosures/TEM cells, systems EMC, and test site measurements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... position. S3.1.2Transmission braking effect. In vehicles having more than one forward transmission gear... driver has activated the vehicle's propulsion system: (a) The engine may stop and restart automatically... activated the vehicle's propulsion system if the vehicle can meet the requirements specified in paragraphs...
Artzy-Randrup, Yael; Alonso, David; Pascual, Mercedes
2010-10-26
Although the spread of drug resistance and the influence of climate change on malaria are most often considered separately, these factors have the potential to interact through altered levels of transmission intensity. The influence of transmission intensity on the evolution of drug resistance has been addressed in theoretical studies from a population genetics' perspective; less is known however on how epidemiological dynamics at the population level modulates this influence. We ask from a theoretical perspective, whether population dynamics can explain non-trivial, non-monotonic, patterns of treatment failure with transmission intensity, and, if so, under what conditions. We then address the implications of warmer temperatures in an East African highland, where, as in other similar regions at the altitudinal edge of malaria's distribution, there has been a pronounced increase of cases from the 1970s to the 1990s. Our theoretical analyses, with a transmission model that includes different levels of immunity, demonstrate that an increase in transmission beyond a threshold can lead to a decrease in drug resistance, as previously shown, but that a second threshold may occur and lead to the re-establishment of drug resistance. Estimates of the increase in transmission intensity from the 1970s to the 1990s for the Kenyan time series, obtained by fitting the two-stage version of the model with an explicit representation of vector dynamics, suggest that warmer temperatures are likely to have moved the system towards the first threshold, and in so doing, to have promoted the faster spread of drug resistance. Climate change and drug resistance can interact and need not be considered as alternative explanations for trends in disease incidence in this region. Non-monotonic patterns of treatment failure with transmission intensity similar to those described as the 'valley phenomenon' for Uganda can result from epidemiological dynamics but under poorly understood assumptions.
What We Know About Tuberculosis Transmission: An Overview.
Churchyard, Gavin; Kim, Peter; Shah, N Sarita; Rustomjee, Roxana; Gandhi, Neel; Mathema, Barun; Dowdy, David; Kasmar, Anne; Cardenas, Vicky
2017-11-03
Tuberculosis remains a global health problem with an enormous burden of disease, estimated at 10.4 million new cases in 2015. To stop the tuberculosis epidemic, it is critical that we interrupt tuberculosis transmission. Further, the interventions required to interrupt tuberculosis transmission must be targeted to high-risk groups and settings. A simple cascade for tuberculosis transmission has been proposed in which (1) a source case of tuberculosis (2) generates infectious particles (3) that survive in the air and (4) are inhaled by a susceptible individual (5) who may become infected and (6) then has the potential to develop tuberculosis. Interventions that target these events will interrupt tuberculosis transmission and accelerate the decline in tuberculosis incidence and mortality. The purpose of this article is to provide a high-level overview of what is known about tuberculosis transmission, using the tuberculosis transmission cascade as a framework, and to set the scene for the articles in this series, which address specific aspects of tuberculosis transmission. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
76 FR 19527 - Medicare Program; Medicare Shared Savings Program: Accountable Care Organizations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-07
... one of the addresses provided below, no later than 5 p.m. on June 6, 2011. ADDRESSES: In commenting... comments by facsimile (FAX) transmission. You may submit comments in one of four ways (please choose only one of the ways listed): 1. Electronically. You may submit electronic comments on this regulation to...
Developing an active emergency medical service system based on WiMAX technology.
Li, Shing-Han; Cheng, Kai-An; Lu, Wen-Hui; Lin, Te-Chang
2012-10-01
The population structure has changed with the aging of population. In the present, elders account for 10.63% of the domestic population and the percentage is still gradually climbing. In other words, the demand for emergency services among elders in home environment is expected to grow in the future. In order to improve the efficiency and quality of emergency care, information technology should be effectively utilized to integrate medical systems and facilities, strengthen human-centered operation designs, and maximize the overall performance. The improvement in the quality and survival rate of emergency care is an important basis for better life and health of all people. Through integrated application of medical information systems and information communication technology, this study proposes a WiMAX-based emergency care system addressing the public demands for convenience, speed, safety, and human-centered operation of emergency care. This system consists of a healthcare service center, emergency medical service hospitals, and emergency ambulances. Using the wireless transmission capability of WiMAX, patients' physiological data can be transmitted from medical measurement facilities to the emergency room and emergency room doctors can provide immediate online instructions on emergency treatment via video and audio transmission. WiMAX technology enables the establishment of active emergency medical services.
Radiation damage and waste management options for the SOMBRERO final focus system and neutron dumps
DOE Office of Scientific and Technical Information (OSTI.GOV)
Latkowski, J F; Meier, W R; Reyes, S
1999-08-09
Previous studies of the safety and environmental aspects of the SOMBRERO inertial fusion energy (IFE) power plant design did not completely address the issues associated with the final focus system. While past work calculated neutron fluences for a grazing incidence metal mirror (GIMM) and a final focus mirror, scattering off of the final optical component was not included, and thus, fluences in the final focus mirror were significantly underestimated. In addition, past work did not consider neutron-induced gamma-rays. Finally, power plant lifetime waste volumes may have been underestimated as neutron activation of the neutron dumps and building structure were notmore » addressed. In the present work, a modified version of the SOMBRERO target building is presented where a significantly larger open solid-angle fraction (5%) is used to enhance beam smoothing of a diode-pumped solid-state laser (DPSSL). The GIMMs are replaced with transmissive fused silica wedges and have been included in three -dimensional neutron and photon transport calculations. This work shows that a power plant with a large open solid-angle fraction, needed for beam smoothing with a DPSSL, is acceptable from tritium breeding, and neutron activation points-of-view.« less
Adaptive low-power listening MAC protocol based on transmission rates.
Hwang, Kwang-il; Yi, Gangman
2014-01-01
Even though existing low-power listening (LPL) protocols have enabled ultra-low-power operation in wireless sensor networks (WSN), they do not address trade-off between energy and delay, since they focused only on energy aspect. However, in recent years, a growing interest in various WSN applications is requiring new design factors, such as minimum delay and higher reliability, as well as energy efficiency. Therefore, in this paper we propose a novel sensor multiple access control (MAC) protocol, transmission rate based adaptive low-power listening MAC protocol (TRA-MAC), which is a kind of preamble-based LPL but is capable of controlling preamble sensing cycle adaptively to transmission rates. Through experiments, it is demonstrated that TRA-MAC enables LPL cycle (LC) and preamble transmission length to adapt dynamically to varying transmission rates, compensating trade-off between energy and response time.
DeMarse, Thomas B; Pan, Liangbin; Alagapan, Sankaraleengam; Brewer, Gregory J; Wheeler, Bruce C
2016-01-01
Transient propagation of information across neuronal assembles is thought to underlie many cognitive processes. However, the nature of the neural code that is embedded within these transmissions remains uncertain. Much of our understanding of how information is transmitted among these assemblies has been derived from computational models. While these models have been instrumental in understanding these processes they often make simplifying assumptions about the biophysical properties of neurons that may influence the nature and properties expressed. To address this issue we created an in vitro analog of a feed-forward network composed of two small populations (also referred to as assemblies or layers) of living dissociated rat cortical neurons. The populations were separated by, and communicated through, a microelectromechanical systems (MEMS) device containing a strip of microscale tunnels. Delayed culturing of one population in the first layer followed by the second a few days later induced the unidirectional growth of axons through the microtunnels resulting in a primarily feed-forward communication between these two small neural populations. In this study we systematically manipulated the number of tunnels that connected each layer and hence, the number of axons providing communication between those populations. We then assess the effect of reducing the number of tunnels has upon the properties of between-layer communication capacity and fidelity of neural transmission among spike trains transmitted across and within layers. We show evidence based on Victor-Purpura's and van Rossum's spike train similarity metrics supporting the presence of both rate and temporal information embedded within these transmissions whose fidelity increased during communication both between and within layers when the number of tunnels are increased. We also provide evidence reinforcing the role of synchronized activity upon transmission fidelity during the spontaneous synchronized network burst events that propagated between layers and highlight the potential applications of these MEMs devices as a tool for further investigation of structure and functional dynamics among neural populations.
DeMarse, Thomas B.; Pan, Liangbin; Alagapan, Sankaraleengam; Brewer, Gregory J.; Wheeler, Bruce C.
2016-01-01
Transient propagation of information across neuronal assembles is thought to underlie many cognitive processes. However, the nature of the neural code that is embedded within these transmissions remains uncertain. Much of our understanding of how information is transmitted among these assemblies has been derived from computational models. While these models have been instrumental in understanding these processes they often make simplifying assumptions about the biophysical properties of neurons that may influence the nature and properties expressed. To address this issue we created an in vitro analog of a feed-forward network composed of two small populations (also referred to as assemblies or layers) of living dissociated rat cortical neurons. The populations were separated by, and communicated through, a microelectromechanical systems (MEMS) device containing a strip of microscale tunnels. Delayed culturing of one population in the first layer followed by the second a few days later induced the unidirectional growth of axons through the microtunnels resulting in a primarily feed-forward communication between these two small neural populations. In this study we systematically manipulated the number of tunnels that connected each layer and hence, the number of axons providing communication between those populations. We then assess the effect of reducing the number of tunnels has upon the properties of between-layer communication capacity and fidelity of neural transmission among spike trains transmitted across and within layers. We show evidence based on Victor-Purpura’s and van Rossum’s spike train similarity metrics supporting the presence of both rate and temporal information embedded within these transmissions whose fidelity increased during communication both between and within layers when the number of tunnels are increased. We also provide evidence reinforcing the role of synchronized activity upon transmission fidelity during the spontaneous synchronized network burst events that propagated between layers and highlight the potential applications of these MEMs devices as a tool for further investigation of structure and functional dynamics among neural populations. PMID:27147977
Two-way digital communications
NASA Astrophysics Data System (ADS)
Glenn, William E.; Daly, Ed
1996-03-01
The communications industry has been rapidly converting from analog to digital communications for audio, video, and data. The initial applications have been concentrating on point-to-multipoint transmission. Currently, a new revolution is occurring in which two-way point-to-point transmission is a rapidly growing market. The system designs for video compression developed for point-to-multipoint transmission are unsuitable for this new market as well as for satellite based video encoding. A new system developed by the Space Communications Technology Center has been designed to address both of these newer applications. An update on the system performance and design will be given.
Single transmission line data acquisition system
Fasching, George E.
1984-01-01
A single transmission line interrogated multiple channel data acquisition system is provided in which a plurality of remote station/sensors monitor specific process variables and transmit measurement values over the single transmission line to a master station when addressed by the master station. Power for all remote stations (up to 980) is provided by driving the line with constant voltage supplied from the master station and automatically maintained independent of the number of remote stations directly connected to the line. The transmission line can be an RG-62 coaxial cable with lengths up to about 10,000 feet with branches up to 500 feet. The remote stations can be attached randomly along the line. The remote stations can be scanned at rates up to 980 channels/second.
Elevation as a proxy for mosquito-borne Zika virus transmission in the Americas
Miniota, Jennifer; Joseph, Heather A.; Brady, Oliver J.; Kraemer, Moritz U. G.; Grills, Ardath W.; Morrison, Stephanie; Esposito, Douglas H.; Nicolucci, Adriano; German, Matthew; Creatore, Maria I.; Nelson, Bradley; Johansson, Michael A.; Brunette, Gary; Hay, Simon I.
2017-01-01
Introduction When Zika virus (ZIKV) first began its spread from Brazil to other parts of the Americas, national-level travel notices were issued, carrying with them significant economic consequences to affected countries. Although regions of some affected countries were likely unsuitable for mosquito-borne transmission of ZIKV, the absence of high quality, timely surveillance data made it difficult to confidently demarcate infection risk at a sub-national level. In the absence of reliable data on ZIKV activity, a pragmatic approach was needed to identify subnational geographic areas where the risk of ZIKV infection via mosquitoes was expected to be negligible. To address this urgent need, we evaluated elevation as a proxy for mosquito-borne ZIKV transmission. Methods For sixteen countries with local ZIKV transmission in the Americas, we analyzed (i) modelled occurrence of the primary vector for ZIKV, Aedes aegypti, (ii) human population counts, and (iii) reported historical dengue cases, specifically across 100-meter elevation levels between 1,500m and 2,500m. Specifically, we quantified land area, population size, and the number of observed dengue cases above each elevation level to identify a threshold where the predicted risks of encountering Ae. aegypti become negligible. Results Above 1,600m, less than 1% of each country’s total land area was predicted to have Ae. aegypti occurrence. Above 1,900m, less than 1% of each country’s resident population lived in areas where Ae. aegypti was predicted to occur. Across all 16 countries, 1.1% of historical dengue cases were reported above 2,000m. Discussion These results suggest low potential for mosquito-borne ZIKV transmission above 2,000m in the Americas. Although elevation is a crude predictor of environmental suitability for ZIKV transmission, its constancy made it a pragmatic input for policy decision-making during this public health emergency. PMID:28542540
A radio-aware routing algorithm for reliable directed diffusion in lossy wireless sensor networks.
Kim, Yong-Pyo; Jung, Euihyun; Park, Yong-Jin
2009-01-01
In Wireless Sensor Networks (WSNs), transmission errors occur frequently due to node failure, battery discharge, contention or interference by objects. Although Directed Diffusion has been considered as a prominent data-centric routing algorithm, it has some weaknesses due to unexpected network errors. In order to address these problems, we proposed a radio-aware routing algorithm to improve the reliability of Directed Diffusion in lossy WSNs. The proposed algorithm is aware of the network status based on the radio information from MAC and PHY layers using a cross-layer design. The cross-layer design can be used to get detailed information about current status of wireless network such as a link quality or transmission errors of communication links. The radio information indicating variant network conditions and link quality was used to determine an alternative route that provides reliable data transmission under lossy WSNs. According to the simulation result, the radio-aware reliable routing algorithm showed better performance in both grid and random topologies with various error rates. The proposed solution suggested the possibility of providing a reliable transmission method for QoS requests in lossy WSNs based on the radio-awareness. The energy and mobility issues will be addressed in the future work.
Yu, Lijie; Wang, Jian; Zhu, Dawei; Leng, Anli; Wangen, Knut R
2016-01-01
Hepatitis B virus (HBV) remains a challenging public-health issue in China. Hepatitis B carriers and patients suffer not only physically but also experience strong discrimination and stigma. China's rural population is 629 million. Thus, there is a great need to understand the situation surrounding HBV-related discrimination in everyday life in rural China. We studied 6,538 participants (≥18 y old) from 42 villages across 7 provinces (districts). Many studies have addressed discrimination against those with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). However, few studies have addressed HBV-related discrimination. We found that the fear of HBV infection, not lack of knowledge about it, predominantly leads to HBV-related discrimination (although limited knowledge is also a cause). Notably, receiving the HBV vaccination contributes to reduced discrimination. In addition, the existence of fewer misunderstandings about false HBV transmission routes plays a more important role in discrimination than does understanding of true HBV transmission routes. Therefore, to reduce HBV-related discrimination, policy makers should consider eliminating HBV-related fear, strengthening adult HBV immunization programs, developing large-scale education dissemination about HBV transmission routes and non-transmission routes, and paying greater attention to target populations. PMID:26211570
Active microwave negative-index metamaterial transmission line with gain.
Jiang, Tao; Chang, Kihun; Si, Li-Ming; Ran, Lixin; Xin, Hao
2011-11-11
We studied the active metamaterial transmission line at microwave frequency. The active composite right-handed or left-handed transmission line was designed to incorporate a germanium tunnel diode with a negative differential resistance property as the gain device at the unit cell level. Measurements of the fabricated planar transmission line structures with one-, two-, and three-unit cells showed that the addition of the dc pumped tunnel diodes not only provided gain but also maintained the left handedness of the transmission line metamaterial. Simulation results agree well with experimental observation. This work demonstrated that negative index material can be obtained with a net gain when an external source is incorporated.
Cell-Cell Transmission Enables HIV-1 to Evade Inhibition by Potent CD4bs Directed Antibodies
Schanz, Merle; Reynell, Lucy; Günthard, Huldrych F.; Rusert, Peter; Trkola, Alexandra
2012-01-01
HIV is known to spread efficiently both in a cell-free state and from cell to cell, however the relative importance of the cell-cell transmission mode in natural infection has not yet been resolved. Likewise to what extent cell-cell transmission is vulnerable to inhibition by neutralizing antibodies and entry inhibitors remains to be determined. Here we report on neutralizing antibody activity during cell-cell transmission using specifically tailored experimental strategies which enable unambiguous discrimination between the two transmission routes. We demonstrate that the activity of neutralizing monoclonal antibodies (mAbs) and entry inhibitors during cell-cell transmission varies depending on their mode of action. While gp41 directed agents remain active, CD4 binding site (CD4bs) directed inhibitors, including the potent neutralizing mAb VRC01, dramatically lose potency during cell-cell transmission. This implies that CD4bs mAbs act preferentially through blocking free virus transmission, while still allowing HIV to spread through cell-cell contacts. Thus providing a plausible explanation for how HIV maintains infectivity and rapidly escapes potent and broadly active CD4bs directed antibody responses in vivo. PMID:22496655
Kwok, Kin On; Read, Jonathan M; Tang, Arthur; Chen, Hong; Riley, Steven; Kam, Kai Man
2018-04-18
Non-hospital residential facilities are important reservoirs for MRSA transmission. However, conclusions and public health implications drawn from the many mathematical models depicting nosocomial MRSA transmission may not be applicable to these settings. Therefore, we reviewed the MRSA transmission dynamics studies in defined non-hospital residential facilities to: (1) provide an overview of basic epidemiology which has been addressed; (2) identify future research direction; and (3) improve future model implementation. A review was conducted by searching related keywords in PUBMED without time restriction as well as internet searches via Google search engine. We included only articles describing the epidemiological transmission pathways of MRSA/community-associated MRSA within and between defined non-hospital residential settings. Among the 10 included articles, nursing homes (NHs) and correctional facilities (CFs) were two settings considered most frequently. Importation of colonized residents was a plausible reason for MRSA outbreaks in NHs, where MRSA was endemic without strict infection control interventions. The importance of NHs over hospitals in increasing nosocomial MRSA prevalence was highlighted. Suggested interventions in NHs included: appropriate staffing level, screening and decolonizing, and hand hygiene. On the other hand, the small population amongst inmates in CFs has no effect on MRSA community transmission. Included models ranged from system-level compartmental models to agent-based models. There was no consensus over the course of disease progression in these models, which were mainly featured with NH residents /CF inmates/ hospital patients as transmission pathways. Some parameters used by these models were outdated or unfit. Importance of NHs has been highlighted from these current studies addressing scattered aspects of MRSA epidemiology. However, the wide variety of non-hospital residential settings suggest that more work is needed before robust conclusions can be drawn. Learning from existing work for hospitals, we identified critical future research direction in this area from infection control, ecological and economic perspectives. From current model deficiencies, we suggest more transmission pathways be specified to depict MRSA transmission, and further empirical studies be stressed to support evidence-based mathematical models of MRSA in non-hospital facilities. Future models should be ready to cope with the aging population structure.
Re-Active Passive devices for control of noise transmission through a panel
NASA Astrophysics Data System (ADS)
Carneal, James P.; Giovanardi, Marco; Fuller, Chris R.; Palumbo, Dan
2008-01-01
Re-Active Passive devices have been developed to control low-frequency (<1000 Hz) noise transmission through a panel. These devices use a combination of active, re-active, and passive technologies packaged into a single unit to control a broad frequency range utilizing the strength of each technology over its best suited frequency range. The Re-Active Passive device uses passive constrained layer damping to cover relatively high-frequency range (>150 Hz), reactive distributed vibration absorber to cover the medium-frequency range (50-200 Hz), and active control for controlling low frequencies (<150 Hz). The actuator was applied to control noise transmission through a panel mounted in the Transmission Loss Test Facility at Virginia Tech. Experimental results are presented for the bare panel, and combinations of passive treatment, reactive treatment, and active control. Results indicate that three Re-Active Passive devices were able to increase the overall broadband (15-1000 Hz) transmission loss by 9.4 dB. These three devices added a total of 285 g to the panel mass of 6.0 kg, or approximately 5%, not including control electronics.
Ecological principles, biodiversity, and the electric utility industry
NASA Astrophysics Data System (ADS)
Temple, Stanley A.
1996-11-01
The synthetic field of conservation biology uses principles derived from many different disciplines to address biodiversity issues. Many of these principles have come from ecology, and two simple ones that seem to relate to many issues involving the utility industry are: (1) “Everything is interconnected” (and should usually stay that way), and (2) “We can never do merely one thing.” The first principle can be applied to both the biotic and physical environments that are impacted by industrial activities. Habitat fragmentation and the loss of physical and biotic connectedness that results are frequently associated with transmission rights-of-way. These problems can be reduced—or even turned into conservation benefits—by careful planning and creative management. The second principle applies to the utility industry's programs to deal with carbon released by burning fossil fuels. Ecological knowledge can allow these programs to contribute to the preservation of biodiversity in addition to addressing a pollution problem. Without careful ecological analyses, industry could easily create new problems while implementing solutions to old ones.
Machine learning for epigenetics and future medical applications.
Holder, Lawrence B; Haque, M Muksitul; Skinner, Michael K
2017-07-03
Understanding epigenetic processes holds immense promise for medical applications. Advances in Machine Learning (ML) are critical to realize this promise. Previous studies used epigenetic data sets associated with the germline transmission of epigenetic transgenerational inheritance of disease and novel ML approaches to predict genome-wide locations of critical epimutations. A combination of Active Learning (ACL) and Imbalanced Class Learning (ICL) was used to address past problems with ML to develop a more efficient feature selection process and address the imbalance problem in all genomic data sets. The power of this novel ML approach and our ability to predict epigenetic phenomena and associated disease is suggested. The current approach requires extensive computation of features over the genome. A promising new approach is to introduce Deep Learning (DL) for the generation and simultaneous computation of novel genomic features tuned to the classification task. This approach can be used with any genomic or biological data set applied to medicine. The application of molecular epigenetic data in advanced machine learning analysis to medicine is the focus of this review.
The DDN (Defense Data Network) Course,
1986-04-01
devices will share the same node-to-node channels. * Simultaneous availability of source and destination is not required. * Speed and code conversion can...address multiple addresses simultaneously 3) Disadvantages of Message Switching Systems Not suited to real time or interactive use * Long and highly...transmission b) Unlike message switching, packet switching requires the -. simultaneous availability of source and destination. 64 -4 ) ..xa...e s
Adams, Philip P.; Flores Avile, Carlos; Jewett, Mollie W.
2017-01-01
Knowledge of the transcriptional responses of vector-borne pathogens at the vector-pathogen interface is critical for understanding disease transmission. Borrelia (Borreliella) burgdorferi, the causative agent of Lyme disease in the United States, is transmitted by the bite of infected Ixodes sp. ticks. It is known that B. burgdorferi has altered patterns of gene expression during tick acquisition, persistence and transmission. Recently, we and others have discovered in vitro expression of RNAs found internal, overlapping, and antisense to annotated open reading frames in the B. burgdorferi genome. However, there is a lack of molecular genetic tools for B. burgdorferi for quantitative, strand-specific, comparative analysis of these transcripts in distinct environments such as the arthropod vector. To address this need, we have developed a dual luciferase reporter system to quantify B. burgdorferi promoter activities in a strand-specific manner. We demonstrate that constitutive expression of a B. burgdorferi codon-optimized Renilla reniformis luciferase gene (rlucBb) allows normalization of the activity of a promoter of interest when fused to the B. burgdorferi codon-optimized Photinus pyralis luciferase gene (flucBb) on the same plasmid. Using the well characterized, differentially regulated, promoters for flagellin (flaBp), outer surface protein A (ospAp) and outer surface protein C (ospCp), we document the efficacy of the dual luciferase system for quantitation of promoter activities during in vitro growth and in infected ticks. Cumulatively, the dual luciferase method outlined herein is the first dual reporter system for B. burgdorferi, providing a novel and highly versatile approach for strand-specific molecular genetic analyses. PMID:28620587
Adams, Philip P; Flores Avile, Carlos; Jewett, Mollie W
2017-01-01
Knowledge of the transcriptional responses of vector-borne pathogens at the vector-pathogen interface is critical for understanding disease transmission. Borrelia ( Borreliella ) burgdorferi , the causative agent of Lyme disease in the United States, is transmitted by the bite of infected Ixodes sp . ticks. It is known that B. burgdorferi has altered patterns of gene expression during tick acquisition, persistence and transmission. Recently, we and others have discovered in vitro expression of RNAs found internal, overlapping, and antisense to annotated open reading frames in the B. burgdorferi genome. However, there is a lack of molecular genetic tools for B. burgdorferi for quantitative, strand-specific, comparative analysis of these transcripts in distinct environments such as the arthropod vector. To address this need, we have developed a dual luciferase reporter system to quantify B. burgdorferi promoter activities in a strand-specific manner. We demonstrate that constitutive expression of a B. burgdorferi codon-optimized Renilla reniformis luciferase gene ( rluc Bb ) allows normalization of the activity of a promoter of interest when fused to the B. burgdorferi codon-optimized Photinus pyralis luciferase gene ( fluc Bb ) on the same plasmid. Using the well characterized, differentially regulated, promoters for flagellin ( flaBp ), outer surface protein A ( ospAp ) and outer surface protein C ( ospCp ), we document the efficacy of the dual luciferase system for quantitation of promoter activities during in vitro growth and in infected ticks. Cumulatively, the dual luciferase method outlined herein is the first dual reporter system for B. burgdorferi , providing a novel and highly versatile approach for strand-specific molecular genetic analyses.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-21
... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No. PHMSA-2012-0024] Pipeline Safety: Information Collection Activities, Revision to Gas Transmission and Gathering Pipeline Systems Annual Report, Gas Transmission and Gathering Pipeline Systems Incident Report...
Epidemiology of Plasmodium vivax Malaria in Peru
Rosas-Aguirre, Angel; Gamboa, Dionicia; Manrique, Paulo; Conn, Jan E.; Moreno, Marta; Lescano, Andres G.; Sanchez, Juan F.; Rodriguez, Hugo; Silva, Hermann; Llanos-Cuentas, Alejandro; Vinetz, Joseph M.
2016-01-01
Malaria in Peru, dominated by Plasmodium vivax, remains a public health problem. The 1990s saw newly epidemic malaria emerge, primarily in the Loreto Department in the Amazon region, including areas near to Iquitos, the capital city, but sporadic malaria transmission also occurred in the 1990s–2000s in both north-coastal Peru and the gold mining regions of southeastern Peru. Although a Global Fund-supported intervention (PAMAFRO, 2005–2010) was temporally associated with a decrease of malaria transmission, from 2012 to the present, both P. vivax and Plasmodium falciparum malaria cases have rapidly increased. The Peruvian Ministry of Health continues to provide artemesinin-based combination therapy for microscopy-confirmed cases of P. falciparum and chloroquine–primaquine for P. vivax. Malaria transmission continues in remote areas nonetheless, where the mobility of humans and parasites facilitates continued reintroduction outside of ongoing surveillance activities, which is critical to address for future malaria control and elimination efforts. Ongoing P. vivax research gaps in Peru include the following: identification of asymptomatic parasitemics, quantification of the contribution of patent and subpatent parasitemics to mosquito transmission, diagnosis of nonparasitemic hypnozoite carriers, and implementation of surveillance for potential emergence of chloroquine- and 8-aminoquinoline-resistant P. vivax. Clinical trials of tafenoquine in Peru have been promising, and glucose-6-phosphate dehydrogenase deficiency in the region has not been observed to be a limitation to its use. Larger-scale challenges for P. vivax (and malaria in general) in Peru include logistical difficulties in accessing remote riverine populations, consequences of government policy and poverty trends, and obtaining international funding for malaria control and elimination. PMID:27799639
What good is SWIR? Passive day comparison of VIS, NIR, and SWIR
NASA Astrophysics Data System (ADS)
Driggers, Ronald G.; Hodgkin, Van; Vollmerhausen, Richard
2013-06-01
This paper is the first of three papers associated with the military benefits of SWIR imaging. This paper describes the benefits associated with passive daytime operations with comparisons of SWIR, NIR, and VIS bands and sensors. This paper includes quantitative findings from previously published papers, analysis of open source data, summaries of various expert analyses, and calculations of notional system performance. We did not accept anecdotal findings as acceptable benefits. Topics include haze and fog penetration, atmospheric transmission, cloud and smoke penetration, target and background contrasts, spectral discrimination, turbulence degradation, and long range target identification. The second and third papers will address passive night imaging and active night imaging.
Transmission of Ebola Viruses: What We Know and What We Do Not Know
Moore, Kristine A.; Kelley, Nicholas S.; Brosseau, Lisa M.; Wong, Gary; Murphy, Frederick A.; Peters, Clarence J.; LeDuc, James W.; Russell, Phillip K.; Van Herp, Michel; Kapetshi, Jimmy; Muyembe, Jean-Jacques T.; Ilunga, Benoit Kebela; Strong, James E.; Grolla, Allen; Wolz, Anja; Kargbo, Brima; Kargbo, David K.; Formenty, Pierre; Sanders, David Avram; Kobinger, Gary P.
2015-01-01
ABSTRACT Available evidence demonstrates that direct patient contact and contact with infectious body fluids are the primary modes for Ebola virus transmission, but this is based on a limited number of studies. Key areas requiring further study include (i) the role of aerosol transmission (either via large droplets or small particles in the vicinity of source patients), (ii) the role of environmental contamination and fomite transmission, (iii) the degree to which minimally or mildly ill persons transmit infection, (iv) how long clinically relevant infectiousness persists, (v) the role that “superspreading events” may play in driving transmission dynamics, (vi) whether strain differences or repeated serial passage in outbreak settings can impact virus transmission, and (vii) what role sylvatic or domestic animals could play in outbreak propagation, particularly during major epidemics such as the 2013–2015 West Africa situation. In this review, we address what we know and what we do not know about Ebola virus transmission. We also hypothesize that Ebola viruses have the potential to be respiratory pathogens with primary respiratory spread. PMID:25698835
Dumyati, Ghinwa; Stone, Nimalie D; Nace, David A; Crnich, Christopher J; Jump, Robin L P
2017-04-01
Nursing home residents are at high risk for colonization and infection with bacterial pathogens that are multidrug-resistant organisms (MDROs). We discuss challenges and potential solutions to support implementing effective infection prevention and control practices in nursing homes. Challenges include a paucity of evidence that addresses MDRO transmission during the care of nursing home residents, limited staff resources in nursing homes, insufficient infection prevention education in nursing homes, and perceptions by nursing home staff that isolation and contact precautions negatively influence the well being of their residents. A small number of studies provide evidence that specifically address these challenges. Their outcomes support a paradigm shift that moves infection prevention and control practices away from a pathogen-specific approach and toward one that focuses on resident risk factors.
zur Nedden, Stephanie; Hawley, Simon; Pentland, Naomi; Hardie, D Grahame; Doney, Alexander S; Frenguelli, Bruno G
2011-04-20
The extent to which brain slices reflect the energetic status of the in vivo brain has been a subject of debate. We addressed this issue to investigate the recovery of energetic parameters and adenine nucleotides in rat hippocampal slices and the influence this has on synaptic transmission and plasticity. We show that, although adenine nucleotide levels recover appreciably within 10 min of incubation, it takes 3 h for a full recovery of the energy charge (to ≥ 0.93) and that incubation of brain slices at 34°C results in a significantly higher ATP/AMP ratio and a threefold lower activity of AMP-activated protein kinase compared with slices incubated at room temperature. Supplementation of artificial CSF with d-ribose and adenine (Rib/Ade) increased the total adenine nucleotide pool of brain slices, which, when corrected for the influence of the dead cut edges, closely approached in vivo values. Rib/Ade did not affect basal synaptic transmission or paired-pulse facilitation but did inhibit long-term potentiation (LTP) induced by tetanic or weak theta-burst stimulation. This decrease in LTP was reversed by strong theta-burst stimulation or antagonizing the inhibitory adenosine A(1) receptor suggesting that the elevated tissue ATP levels had resulted in greater activity-dependent adenosine release during LTP induction. This was confirmed by direct measurement of adenosine release with adenosine biosensors. These observations provide new insight into the recovery of adenine nucleotides after slice preparation, the sources of loss of such compounds in brain slices, the means by which to restore them, and the functional consequences of doing so.
Recent progress in immune-based interventions to prevent HIV-1 transmission to children.
Voronin, Yegor; Jani, Ilesh; Graham, Barney S; Cunningham, Coleen K; Mofenson, Lynne M; Musoke, Philippa M; Permar, Sallie R; Scarlatti, Gabriella
2017-12-01
Globally, 150,000 new paediatric human immunodeficiency virus type 1 (HIV-1) infections occurred in 2015. There remain complex challenges to the global elimination of paediatric HIV-1 infection. Thus, for the global community to achieve elimination of new paediatric HIV-1 infections, innovative approaches need to be explored. Immune-based approaches to prevention of mother-to-child transmission (MTCT) may help fill some of the remaining gaps and provide new opportunities to achieve an AIDS-free generation. Immune-based interventions to prevent MTCT of HIV-1 may include paediatric HIV vaccines and passive immunization approaches. Recent discoveries providing evidence of robust immune responses to HIV in infants open new and exciting prospects for paediatric HIV vaccines. Moreover, successful vaccination of infants has a different set of requirements than vaccination of adults and may be easier to achieve. Proof-of-concept has been established over the last two decades that passively administered HIV-1 Env-specific monoclonal antibody (mAbs) can prevent chimeric simian human immunodeficiency virus (SHIV) transmission to newborn nonhuman primates. There has been tremendous progress in isolating and characterizing broadly neutralizing antibodies to HIV, and clinical testing of these antibodies for treatment and prevention in both infants and adults is a major effort in the field. Immune-based interventions need to be actively explored as they can provide critically important tools to address persistent challenges in MTCT prevention. It is a pivotal time for the field with active discussions on the best strategy to further reduce HIV infection of infants and accomplish the World Health Organization Fast-Track 2030 goals to eliminate new paediatric HIV infections. © 2017 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.
Dietz, Vance; Rota, Jennifer; Izurieta, Héctor; Carrasco, Peter; Bellini, William
2004-01-01
The Americas have set a goal of interrupting indigenous transmission of measles using a strategy developed by the Pan American Health Organization (PAHO). This strategy includes recommendations for vaccination activities to achieve and sustain high immunity in the population and is complemented by sensitive epidemiological surveillance systems developed to monitor illnesses characterized by febrile rash, and to provide effective virological and serological surveillance. A key component in ensuring the success of the programme has been a laboratory network comprising 22 national laboratories including reference centres. Commercially available indirect enzyme immunoassay kits (EIA) for immunoglobulin M (IgM)-class antibodies are currently being used throughout the region. However, because there are few or no true measles cases in the region, the positive predictive value of these diagnostic tests has decreased. False-positive results of IgM tests can also occur as a result of testing suspected measles cases with exanthemata caused by Parvovirus B19, rubella and Human herpesvirus 6, among others. In addition, as countries maintain high levels of vaccination activity and increased surveillance of rash and fever, the notification of febrile rash illness in recently vaccinated people can be anticipated. Thus, managers in the measles elimination programme must be prepared to address the interpretation of a positive result of a laboratory test for measles IgM when clinical and epidemiological data may indicate that the case is not measles. The interpretation of an IgM-positive test under different circumstances and the definition of a vaccine-related rash illness in a setting of greatly reduced, or absent, transmission of measles is discussed. PMID:15640921
Pathogen Transmission from Humans to Great Apes is a Growing Threat to Primate Conservation.
Dunay, Emily; Apakupakul, Kathleen; Leard, Stephen; Palmer, Jamie L; Deem, Sharon L
2018-01-23
All six great ape species are listed as endangered or critically endangered by the IUCN and experiencing decreasing population trends. One of the threats to these non-human primates is the transmission of pathogens from humans. We conducted a literature review on occurrences of pathogen transmission from humans to great apes to highlight this often underappreciated issue. In total, we found 33 individual occurrences of probable or confirmed pathogen transmission from humans to great apes: 23 involved both pathogen and disease transmission, 7 pathogen transmission only, 2 positive antibody titers to zoonotic pathogens, and 1 pathogen transmission with probable disease. Great ape populations were categorized into captive, semi-free-living, and free-living conditions. The majority of occurrences involved chimpanzees (Pan troglodytes) (n = 23) or mountain gorillas (Gorilla beringei beringei) (n = 8). These findings have implications for conservation efforts and management of endangered great ape populations. Future efforts should focus on monitoring and addressing zoonotic pathogen and disease transmission between humans, great ape species, and other taxa to ensure the health of humans, wild and domestic animals, and the ecosystems we share.
ACEE composite structures technology
NASA Technical Reports Server (NTRS)
James, A. M.
1984-01-01
Topics addressed include: strength and hygrothermal response of L-1011 fin components; wing fuel containment and damage tolerance development; impact dynamics; acoustic transmission; fuselage structure; composite transport wing technology development; spar/assembly concepts.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liun, Edwaren, E-mail: edwaren@batan.go.id; Suparman, E-mail: edwaren@batan.go.id
Regarding nuclear power plant development in Bangka Island, it can be estimated that produced power will be oversupply for the Bangka Island and needs to transmit to Sumatra or Java Island. The distance between the regions or islands causing considerable loss of power in transmission by alternating current, and a wide range of technical and economical issues. The objective of this paper addresses to economics analysis of direct current transmission system to overcome those technical problem. Direct current transmission has a stable characteristic, so that the power delivery from Bangka to Sumatra or Java in a large scale efficiently andmore » reliably can be done. HVDC system costs depend on the power capacity applied to the system and length of the transmission line in addition to other variables that may be different.« less
Molecules to modeling: Toxoplasma gondii oocysts at the human–animal–environment interface
VanWormer, Elizabeth; Fritz, Heather; Shapiro, Karen; Mazet, Jonna A.K.; Conrad, Patricia A.
2013-01-01
Environmental transmission of extremely resistant Toxoplasma gondii oocysts has resulted in infection of diverse species around the world, leading to severe disease and deaths in human and animal populations. This review explores T. gondii oocyst shedding, survival, and transmission, emphasizing the importance of linking laboratory and landscape from molecular characterization of oocysts to watershed-level models of oocyst loading and transport in terrestrial and aquatic systems. Building on discipline-specific studies, a One Health approach incorporating tools and perspectives from diverse fields and stakeholders has contributed to an advanced understanding of T. gondii and is addressing transmission at the rapidly changing human–animal–environment interface. PMID:23218130
High density array fabrication and readout method for a fiber optic biosensor
Pinkel, Daniel; Gray, Joe
1997-01-01
The invention relates to the fabrication and use of biosensors comprising a plurality of optical fibers each fiber having attached to its "sensor end" biological "binding partners" (molecules that specifically bind other molecules to form a binding complex such as antibody-antigen, lectin-carbohydrate, nucleic acid-nucleic acid, biotin-avidin, etc.). The biosensor preferably bears two or more different species of biological binding partner. The sensor is fabricated by providing a plurality of groups of optical fibers. Each group is treated as a batch to attach a different species of biological binding partner to the sensor ends of the fibers comprising that bundle. Each fiber, or group of fibers within a bundle, may be uniquely identified so that the fibers, or group of fibers, when later combined in an array of different fibers, can be discretely addressed. Fibers or groups of fibers are then selected and discretely separated from different bundles. The discretely separated fibers are then combined at their sensor ends to produce a high density sensor array of fibers capable of assaying simultaneously the binding of components of a test sample to the various binding partners on the different fibers of the sensor array. The transmission ends of the optical fibers are then discretely addressed to detectors--such as a multiplicity of optical sensors. An optical signal, produced by binding of the binding partner to its substrate to form a binding complex, is conducted through the optical fiber or group of fibers to a detector for each discrete test. By examining the addressed transmission ends of fibers, or groups of fibers, the addressed transmission ends can transmit unique patterns assisting in rapid sample identification by the sensor.
High density array fabrication and readout method for a fiber optic biosensor
Pinkel, Daniel; Gray, Joe; Albertson, Donna G.
2000-01-01
The invention relates to the fabrication and use of biosensors comprising a plurality of optical fibers each fiber having attached to its "sensor end" biological "binding partners" (molecules that specifically bind other molecules to form a binding complex such as antibody-antigen, lectin-carbohydrate, nucleic acid-nucleic acid, biotin-avidin, etc.). The biosensor preferably bears two or more different species of biological binding partner. The sensor is fabricated by providing a plurality of groups of optical fibers. Each group is treated as a batch to attach a different species of biological binding partner to the sensor ends of the fibers comprising that bundle. Each fiber, or group of fibers within a bundle, may be uniquely identified so that the fibers, or group of fibers, when later combined in an array of different fibers, can be discretely addressed. Fibers or groups of fibers are then selected and discretely separated from different bundles. The discretely separated fibers are then combined at their sensor ends to produce a high density sensor array of fibers capable of assaying simultaneously the binding of components of a test sample to the various binding partners on the different fibers of the sensor array. The transmission ends of the optical fibers are then discretely addressed to detectors--such as a multiplicity of optical sensors. An optical signal, produced by binding of the binding partner to its substrate to form a binding complex, is conducted through the optical fiber or group of fibers to a detector for each discrete test. By examining the addressed transmission ends of fibers, or groups of fibers, the addressed transmission ends can transmit unique patterns assisting in rapid sample identification by the sensor.
High density array fabrication and readout method for a fiber optic biosensor
Pinkel, Daniel; Gray, Joe; Albertson, Donna G.
2002-01-01
The invention relates to the fabrication and use of biosensors comprising a plurality of optical fibers each fiber having attached to its "sensor end" biological "binding partners" (molecules that specifically bind other molecules to form a binding complex such as antibody-antigen, lectin-carbohydrate, nucleic acid-nucleic acid, biotin-avidin, etc.). The biosensor preferably bears two or more different species of biological binding partner. The sensor is fabricated by providing a plurality of groups of optical fibers. Each group is treated as a batch to attach a different species of biological binding partner to the sensor ends of the fibers comprising that bundle. Each fiber, or group of fibers within a bundle, may be uniquely identified so that the fibers, or group of fibers, when later combined in an array of different fibers, can be discretely addressed. Fibers or groups of fibers are then selected and discretely separated from different bundles. The discretely separated fibers are then combined at their sensor ends to produce a high density sensor array of fibers capable of assaying simultaneously the binding of components of a test sample to the various binding partners on the different fibers of the sensor array. The transmission ends of the optical fibers are then discretely addressed to detectors--such as a multiplicity of optical sensors. An optical signal, produced by binding of the binding partner to its substrate to form a binding complex, is conducted through the optical fiber or group of fibers to a detector for each discrete test. By examining the addressed transmission ends of fibers, or groups of fibers, the addressed transmission ends can transmit unique patterns assisting in rapid sample identification by the sensor.
High density array fabrication and readout method for a fiber optic biosensor
Pinkel, D.; Gray, J.
1997-11-25
The invention relates to the fabrication and use of biosensors comprising a plurality of optical fibers each fiber having attached to its ``sensor end`` biological ``binding partners`` (molecules that specifically bind other molecules to form a binding complex such as antibody-antigen, lectin-carbohydrate, nucleic acid-nucleic acid, biotin-avidin, etc.). The biosensor preferably bears two or more different species of biological binding partner. The sensor is fabricated by providing a plurality of groups of optical fibers. Each group is treated as a batch to attach a different species of biological binding partner to the sensor ends of the fibers comprising that bundle. Each fiber, or group of fibers within a bundle, may be uniquely identified so that the fibers, or group of fibers, when later combined in an array of different fibers, can be discretely addressed. Fibers or groups of fibers are then selected and discretely separated from different bundles. The discretely separated fibers are then combined at their sensor ends to produce a high density sensor array of fibers capable of assaying simultaneously the binding of components of a test sample to the various binding partners on the different fibers of the sensor array. The transmission ends of the optical fibers are then discretely addressed to detectors--such as a multiplicity of optical sensors. An optical signal, produced by binding of the binding partner to its substrate to form a binding complex, is conducted through the optical fiber or group of fibers to a detector for each discrete test. By examining the addressed transmission ends of fibers, or groups of fibers, the addressed transmission ends can transmit unique patterns assisting in rapid sample identification by the sensor. 9 figs.
Long-period fiber phase grating devices
NASA Astrophysics Data System (ADS)
Stegall, David Brian
In recent years, the explosive growth of the internet has virtually surpassed the limits of the global communications infrastructure. As a result, the fiber- optic communications industry is spearheading research and development to transmit information at ever increasing rates and over longer distances. The industry faces several obstacles to improving the performance of these systems. One problem is dispersion, which manifests at faster transmission rates when pulse spreading and distortion scramble the signal. Furthermore, high transmission powers needed for longer distances introduce deleterious optical nonlinearity phenomenon. Several waveguide and bulk devices have been implemented to address these issues, but each have shortcomings. Many of these problems and challenges have also impacted other fiber-optic industries, such as sensor systems. Long- period optical fiber gratings pose simple solutions to these problems and offer novel applications previously impractical through any other means. In this dissertation, research is presented in which modeling and fabrication of long-period gratings is improved over existing techniques by incorporating the effects of waveguide dispersion. An arbitrary dispersion also can be introduced into a long-period grating intentionally and a theoretical examination is made relating the chirp of a long-period grating and the resulting dispersion. In addition, several device applications such as a biological sensor and the concept of an actively controlled transmission spectrum of a long-period grating are explored. Finally, multiple in-series Bragg and long- period gratings are investigated for novel device configurations.
Liu, Tiemin; Kong, Dong; Shah, Bhavik P.; Ye, Chianping; Koda, Shuichi; Saunders, Arpiar; Ding, Jun B.; Yang, Zongfang; Sabatini, Bernardo L.; Lowell, Bradford B.
2012-01-01
SUMMARY AgRP neuron activity drives feeding and weight gain while that of nearby POMC neurons does the opposite. However, the role of excitatory glutamatergic input in controlling these neurons is unknown. To address this question, we generated mice lacking NMDA receptors (NMDARs) on either AgRP or POMC neurons. Deletion of NMDARs from AgRP neurons markedly reduced weight, body fat and food intake whereas deletion from POMC neurons had no effect. Activation of AgRP neurons by fasting, as assessed by c-Fos, Agrp and Npy mRNA expression, AMPA receptor-mediated EPSCs, depolarization and firing rates, required NMDARs. Furthermore, AgRP but not POMC neurons have dendritic spines and increased glutamatergic input onto AgRP neurons caused by fasting was paralleled by an increase in spines, suggesting fasting induced synaptogenesis and spinogenesis. Thus glutamatergic synaptic transmission and its modulation by NMDARs play key roles in controlling AgRP neurons and determining the cellular and behavioral response to fasting. PMID:22325203
Banks, Paul James; Burroughs, Amelia Caroline; Barker, Gareth Robert Isaac; Brown, Jon Thomas; Warburton, Elizabeth Clea; Bashir, Zafar Iqbal
2015-01-01
Functional connectivity between the hippocampus and prefrontal cortex (PFC) is essential for associative recognition memory and working memory. Disruption of hippocampal–PFC synchrony occurs in schizophrenia, which is characterized by hypofunction of NMDA receptor (NMDAR)-mediated transmission. We demonstrate that activity of dopamine D2-like receptors (D2Rs) leads selectively to long-term depression (LTD) of hippocampal–PFC NMDAR-mediated synaptic transmission. We show that dopamine-dependent LTD of NMDAR-mediated transmission profoundly disrupts normal synaptic transmission between hippocampus and PFC. These results show how dopaminergic activation induces long-term hypofunction of NMDARs, which can contribute to disordered functional connectivity, a characteristic that is a hallmark of psychiatric disorders such as schizophrenia. PMID:26286993
Active Time Domain Reflectometry for Tamper Indication in Unattended Safeguards Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheen, David M.; Smith, Leon E.; Tedeschi, Jonathan R.
2015-07-14
The International Atomic Energy Agency (IAEA) continues to expand its use of unattended measurement systems. An increasing number of systems and an expanding family of instruments create challenges in terms of deployment efficiency and the implementation of data authentication measures. In collaboration with the IAEA, tamper-indicating measures to address data-transmission authentication challenges with unattended safeguards systems are under investigation. Pacific Northwest National Laboratory is studying the viability of active time-domain reflectometry (TDR) along two parallel but interconnected paths: (1) swept-frequency TDR as the highly flexible, laboratory gold standard to which field-deployable options can be compared, and (2) a low-cost commerciallymore » available spread-spectrum TDR technology as one option for field implementation. This paper describes the TDR methods under investigation and the associated benchtop test-bed, tampering scenarios of interest,, and viability measurement results to date (e.g., comparison of relative sensitivity to tamper scenarios).« less
Information extraction and transmission techniques for spaceborne synthetic aperture radar images
NASA Technical Reports Server (NTRS)
Frost, V. S.; Yurovsky, L.; Watson, E.; Townsend, K.; Gardner, S.; Boberg, D.; Watson, J.; Minden, G. J.; Shanmugan, K. S.
1984-01-01
Information extraction and transmission techniques for synthetic aperture radar (SAR) imagery were investigated. Four interrelated problems were addressed. An optimal tonal SAR image classification algorithm was developed and evaluated. A data compression technique was developed for SAR imagery which is simple and provides a 5:1 compression with acceptable image quality. An optimal textural edge detector was developed. Several SAR image enhancement algorithms have been proposed. The effectiveness of each algorithm was compared quantitatively.
The Role of Early-Phase Transmission in the Spread of Yersinia pestis
EISEN, REBECCA J.; DENNIS, DAVID T.; GAGE, KENNETH L.
2015-01-01
Early-phase transmission (EPT) of Yersinia pestis by unblocked fleas is a well-documented, replicable phenomenon with poorly defined mechanisms. We review evidence demonstrating EPT and current knowledge on its biological and biomechanical processes. We discuss the importance of EPT in the epizootic spread of Y. pestis and its role in the maintenance of plague bacteria in nature. We further address the role of EPT in the epidemiology of plague. PMID:26336267
Re-active Passive (RAP) Devices for Control of Noise Transmission through a Panel
NASA Technical Reports Server (NTRS)
Carneal, James P.; Giovanardi, Marco; Fuller, Chris R.; Palumbo, Daniel L.
2008-01-01
Re-Active Passive (RAP) devices have been developed to control low frequency (<1000 Hz) noise transmission through a panel. These devices use a combination of active, re-active, and passive technologies packaged into a single unit to control a broad frequency range utilizing the strength of each technology over its best suited frequency range. The RAP device uses passive constrained layer damping to cover the relatively high frequency range (>200 Hz), reactive distributed vibration absorber) to cover the medium frequency range (75 to 250 Hz), and active control for controlling low frequencies (<200 Hz). The device was applied to control noise transmission through a panel mounted in a transmission loss test facility. Experimental results are presented for the bare panel, and combinations of passive treatment, reactive treatment, and active control. Results indicate that three RAP devices were able to increase the overall broadband (15-1000 Hz) transmission loss by 9.4 dB. These three devices added a total of 285 grams to the panel mass of 6.0 kg, or approximately 5%, not including control electronics.
Drivers of Tuberculosis Transmission.
Mathema, Barun; Andrews, Jason R; Cohen, Ted; Borgdorff, Martien W; Behr, Marcel; Glynn, Judith R; Rustomjee, Roxana; Silk, Benjamin J; Wood, Robin
2017-11-03
Measuring tuberculosis transmission is exceedingly difficult, given the remarkable variability in the timing of clinical disease after Mycobacterium tuberculosis infection; incident disease can result from either a recent (ie, weeks to months) or a remote (ie, several years to decades) infection event. Although we cannot identify with certainty the timing and location of tuberculosis transmission for individuals, approaches for estimating the individual probability of recent transmission and for estimating the fraction of tuberculosis cases due to recent transmission in populations have been developed. Data used to estimate the probable burden of recent transmission include tuberculosis case notifications in young children and trends in tuberculin skin test and interferon γ-release assays. More recently, M. tuberculosis whole-genome sequencing has been used to estimate population levels of recent transmission, identify the distribution of specific strains within communities, and decipher chains of transmission among culture-positive tuberculosis cases. The factors that drive the transmission of tuberculosis in communities depend on the burden of prevalent tuberculosis; the ways in which individuals live, work, and interact (eg, congregate settings); and the capacity of healthcare and public health systems to identify and effectively treat individuals with infectious forms of tuberculosis. Here we provide an overview of these factors, describe tools for measurement of ongoing transmission, and highlight knowledge gaps that must be addressed. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Towards tuberculosis elimination: an action framework for low-incidence countries.
Lönnroth, Knut; Migliori, Giovanni Battista; Abubakar, Ibrahim; D'Ambrosio, Lia; de Vries, Gerard; Diel, Roland; Douglas, Paul; Falzon, Dennis; Gaudreau, Marc-Andre; Goletti, Delia; González Ochoa, Edilberto R; LoBue, Philip; Matteelli, Alberto; Njoo, Howard; Solovic, Ivan; Story, Alistair; Tayeb, Tamara; van der Werf, Marieke J; Weil, Diana; Zellweger, Jean-Pierre; Abdel Aziz, Mohamed; Al Lawati, Mohamed R M; Aliberti, Stefano; Arrazola de Oñate, Wouter; Barreira, Draurio; Bhatia, Vineet; Blasi, Francesco; Bloom, Amy; Bruchfeld, Judith; Castelli, Francesco; Centis, Rosella; Chemtob, Daniel; Cirillo, Daniela M; Colorado, Alberto; Dadu, Andrei; Dahle, Ulf R; De Paoli, Laura; Dias, Hannah M; Duarte, Raquel; Fattorini, Lanfranco; Gaga, Mina; Getahun, Haileyesus; Glaziou, Philippe; Goguadze, Lasha; Del Granado, Mirtha; Haas, Walter; Järvinen, Asko; Kwon, Geun-Yong; Mosca, Davide; Nahid, Payam; Nishikiori, Nobuyuki; Noguer, Isabel; O'Donnell, Joan; Pace-Asciak, Analita; Pompa, Maria G; Popescu, Gilda G; Robalo Cordeiro, Carlos; Rønning, Karin; Ruhwald, Morten; Sculier, Jean-Paul; Simunović, Aleksandar; Smith-Palmer, Alison; Sotgiu, Giovanni; Sulis, Giorgia; Torres-Duque, Carlos A; Umeki, Kazunori; Uplekar, Mukund; van Weezenbeek, Catharina; Vasankari, Tuula; Vitillo, Robert J; Voniatis, Constantia; Wanlin, Maryse; Raviglione, Mario C
2015-04-01
This paper describes an action framework for countries with low tuberculosis (TB) incidence (<100 TB cases per million population) that are striving for TB elimination. The framework sets out priority interventions required for these countries to progress first towards "pre-elimination" (<10 cases per million) and eventually the elimination of TB as a public health problem (less than one case per million). TB epidemiology in most low-incidence countries is characterised by a low rate of transmission in the general population, occasional outbreaks, a majority of TB cases generated from progression of latent TB infection (LTBI) rather than local transmission, concentration to certain vulnerable and hard-to-reach risk groups, and challenges posed by cross-border migration. Common health system challenges are that political commitment, funding, clinical expertise and general awareness of TB diminishes as TB incidence falls. The framework presents a tailored response to these challenges, grouped into eight priority action areas: 1) ensure political commitment, funding and stewardship for planning and essential services; 2) address the most vulnerable and hard-to-reach groups; 3) address special needs of migrants and cross-border issues; 4) undertake screening for active TB and LTBI in TB contacts and selected high-risk groups, and provide appropriate treatment; 5) optimise the prevention and care of drug-resistant TB; 6) ensure continued surveillance, programme monitoring and evaluation and case-based data management; 7) invest in research and new tools; and 8) support global TB prevention, care and control. The overall approach needs to be multisectorial, focusing on equitable access to high-quality diagnosis and care, and on addressing the social determinants of TB. Because of increasing globalisation and population mobility, the response needs to have both national and global dimensions. The content of this work is ©the authors or their employers. Design and branding are ©ERS 2015.
Morrow, Benjamin M.; Cerreta, E. K.; McCabe, R. J.; ...
2015-05-14
In-situ straining was used to study deformation behavior of hexagonal close-packed (hcp) metals.Twinning and dislocation motion, both essential to plasticity in hcp materials, were observed.Typically, these processes are characterized post-mortem by examining remnant microstructural features after straining has occurred. By imposing deformation during imaging, direct observation of active deformation mechanisms is possible. This work focuses on straining of structural metals in a transmission electron microscope (TEM), and a recently developed technique that utilizes familiar procedures and equipment to increase ease of experiments. In-situ straining in a TEM presents several advantages over conventional post-mortem characterization, most notably time-resolution of deformation andmore » streamlined identification of active deformation mechanisms. Drawbacks to the technique and applicability to other studies are also addressed. In-situ straining is used to study twin boundary motion in hcp magnesium. A {101¯2} twin was observed during tensile and compressive loading. Twin-dislocation interactions are directly observed. Notably, dislocations are observed to remain mobile, even after multiple interactions with twin boundaries, a result which suggests that Basinki’s dislocation transformation mechanism by twinning is not present in hcp metals. The coupling of in-situ straining with traditional post-mortem characterization yields more detailed information about material behavior during deformation than either technique alone.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tor, Osman Bulent; Shahidehpour, Mohammad
In moving toward restructuring, transmission expansion planning is a major challenge. The authors offer a general perspective on TEP issues, then address the specific challenges in Turkey and propose several strategies toward managing physical and financial risks in that country. (author)
Active control of transmission loss with smart foams.
Kundu, Abhishek; Berry, Alain
2011-02-01
Smart foams combine the complimentary advantages of passive foam material and spatially distributed piezoelectric actuator embedded in it for active noise control applications. In this paper, the problem of improving the transmission loss of smart foams using active control strategies has been investigated both numerically and experimentally inside a waveguide under the condition of plane wave propagation. The finite element simulation of a coupled noise control system has been undertaken with three different smart foam designs and their effectiveness in cancelling the transmitted wave downstream of the smart foam have been studied. The simulation results provide insight into the physical phenomenon of active noise cancellation and explain the impact of the smart foam designs on the optimal active control results. Experimental studies aimed at implementing the real-time control for transmission loss optimization have been performed using the classical single input/single output filtered-reference least mean squares algorithm. The active control results with broadband and single frequency primary source inputs demonstrate a good improvement in the transmission loss of the smart foams. The study gives a comparative description of the transmission and absorption control problems in light of the modification of the vibration response of the piezoelectric actuator under active control.
Cross-layer model design in wireless ad hoc networks for the Internet of Things.
Yang, Xin; Wang, Ling; Xie, Jian; Zhang, Zhaolin
2018-01-01
Wireless ad hoc networks can experience extreme fluctuations in transmission traffic in the Internet of Things, which is widely used today. Currently, the most crucial issues requiring attention for wireless ad hoc networks are making the best use of low traffic periods, reducing congestion during high traffic periods, and improving transmission performance. To solve these problems, the present paper proposes a novel cross-layer transmission model based on decentralized coded caching in the physical layer and a content division multiplexing scheme in the media access control layer. Simulation results demonstrate that the proposed model effectively addresses these issues by substantially increasing the throughput and successful transmission rate compared to existing protocols without a negative influence on delay, particularly for large scale networks under conditions of highly contrasting high and low traffic periods.
Cross-layer model design in wireless ad hoc networks for the Internet of Things
Wang, Ling; Xie, Jian; Zhang, Zhaolin
2018-01-01
Wireless ad hoc networks can experience extreme fluctuations in transmission traffic in the Internet of Things, which is widely used today. Currently, the most crucial issues requiring attention for wireless ad hoc networks are making the best use of low traffic periods, reducing congestion during high traffic periods, and improving transmission performance. To solve these problems, the present paper proposes a novel cross-layer transmission model based on decentralized coded caching in the physical layer and a content division multiplexing scheme in the media access control layer. Simulation results demonstrate that the proposed model effectively addresses these issues by substantially increasing the throughput and successful transmission rate compared to existing protocols without a negative influence on delay, particularly for large scale networks under conditions of highly contrasting high and low traffic periods. PMID:29734355
Health monitoring system for transmission shafts based on adaptive parameter identification
NASA Astrophysics Data System (ADS)
Souflas, I.; Pezouvanis, A.; Ebrahimi, K. M.
2018-05-01
A health monitoring system for a transmission shaft is proposed. The solution is based on the real-time identification of the physical characteristics of the transmission shaft i.e. stiffness and damping coefficients, by using a physical oriented model and linear recursive identification. The efficacy of the suggested condition monitoring system is demonstrated on a prototype transient engine testing facility equipped with a transmission shaft capable of varying its physical properties. Simulation studies reveal that coupling shaft faults can be detected and isolated using the proposed condition monitoring system. Besides, the performance of various recursive identification algorithms is addressed. The results of this work recommend that the health status of engine dynamometer shafts can be monitored using a simple lumped-parameter shaft model and a linear recursive identification algorithm which makes the concept practically viable.
Ultrasound beam transmission using a discretely orthogonal Gaussian aperture basis
NASA Astrophysics Data System (ADS)
Roberts, R. A.
2018-04-01
Work is reported on development of a computational model for ultrasound beam transmission at an arbitrary geometry transmission interface for generally anisotropic materials. The work addresses problems encountered when the fundamental assumptions of ray theory do not hold, thereby introducing errors into ray-theory-based transmission models. Specifically, problems occur when the asymptotic integral analysis underlying ray theory encounters multiple stationary phase points in close proximity, due to focusing caused by concavity on either the entry surface or a material slowness surface. The approach presented here projects integrands over both the transducer aperture and the entry surface beam footprint onto a Gaussian-derived basis set, thereby distributing the integral over a summation of second-order phase integrals which are amenable to single stationary phase point analysis. Significantly, convergence is assured provided a sufficiently fine distribution of basis functions is used.
Lyngstad, Torkild Hovde; Engelhardt, Henriette
2009-07-01
Whether a couple remain married or divorce has repeatedly been shown to be of importance for the marital stability of their children. This paper addresses the related question of whether the intergenerational transmission of divorce is contingent on the age at which parents divorced and the sex of the spouse who experienced the parents' divorce. Using a population-wide data-set on Norwegian first marriages followed from 1980 to 2003, we find that the intergenerational transmission hypothesis holds also for Norway, that this relationship is stronger for women than for men, and that there is a negative age gradient in the transmission effect for women. The experience of multiple family transitions, such as a parent's remarriage or a second divorce, does not affect couples' divorce risk.
Compressive Oversampling for Robust Data Transmission in Sensor Networks
2010-01-01
Mani B. Srivastava University of California, Los Angeles Ting He, Chatschik Bisdikian IBM T. J. Watson Research Center Abstract—Data loss in...TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS( ES ) University of California, Los Angeles,Los Angeles,CA,90095 8...PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS( ES ) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S
Novel technical solutions for wireless ECG transmission & analysis in the age of the internet cloud.
Al-Zaiti, Salah S; Shusterman, Vladimir; Carey, Mary G
2013-01-01
Current guidelines recommend early reperfusion therapy for ST-elevation myocardial infarction (STEMI) within 90 min of first medical encounter. Telecardiology entails the use of advanced communication technologies to transmit the prehospital 12-lead electrocardiogram (ECG) to offsite cardiologists for early triage to the cath lab; which has been shown to dramatically reduce door-to-balloon time and total mortality. However, hospitals often find adopting ECG transmission technologies very challenging. The current review identifies seven major technical challenges of prehospital ECG transmission, including: paramedics inconvenience and transport delay; signal noise and interpretation errors; equipment malfunction and transmission failure; reliability of mobile phone networks; lack of compliance with the standards of digital ECG formats; poor integration with electronic medical records; and costly hardware and software pre-requisite installation. Current and potential solutions to address each of these technical challenges are discussed in details and include: automated ECG transmission protocols; annotatable waveform-based ECGs; optimal routing solutions; and the use of cloud computing systems rather than vendor-specific processing stations. Nevertheless, strategies to monitor transmission effectiveness and patient outcomes are essential to sustain initial gains of implementing ECG transmission technologies. © 2013.
Orlofske, Sarah A; Flaxman, Samuel M; Joseph, Maxwell B; Fenton, Andy; Melbourne, Brett A; Johnson, Pieter T J
2018-05-01
Understanding pathogen transmission is crucial for predicting and managing disease. Nonetheless, experimental comparisons of alternative functional forms of transmission remain rare, and those experiments that are conducted are often not designed to test the full range of possible forms. To differentiate among 10 candidate transmission functions, we used a novel experimental design in which we independently varied four factors-duration of exposure, numbers of parasites, numbers of hosts and parasite density-in laboratory infection experiments. We used interactions between amphibian hosts and trematode parasites as a model system and all candidate models incorporated parasite depletion. An additional manipulation involving anaesthesia addressed the effects of host behaviour on transmission form. Across all experiments, nonlinear transmission forms involving either a power law or a negative binomial function were the best-fitting models and consistently outperformed the linear density-dependent and density-independent functions. By testing previously published data for two other host-macroparasite systems, we also found support for the same nonlinear transmission forms. Although manipulations of parasite density are common in transmission studies, the comprehensive set of variables tested in our experiments revealed that variation in density alone was least likely to differentiate among competing transmission functions. Across host-pathogen systems, nonlinear functions may often more accurately represent transmission dynamics and thus provide more realistic predictions for infection. © 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
NASA Technical Reports Server (NTRS)
Campanella, S. J.; Chitre, D. M.
1988-01-01
The single factor that irrevocably distinguishes geostationary satellite telephony transmission from terrestrial transmission is the greater propagation delay over satellite links. This difference has always provoked vigorous debate over the impact of delay on the subscribers using services incorporating satellite links. The issue is addressed from a variety of directions including human factors studies, laboratory subjective tests that evaluate delay with and without echo, and field tests that obtain data on the opinion of subscribers regarding the quality of service of operational circuits in both national U.S. domestic and international trans-Atlantic network. The tests involved the use of both echo suppressors and echo cancellers.
RAPTOR Transmissivity and Cloud Climatology Study. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eis, K.E.; Vonder Haar, T.H.; Forsythe, J.
1993-01-01
The RAPTOR Transmissivity Study (RTS) was funded by Lawrence Livermore National Laboratory (LLNL) under a sub contract to support the U.S. Army`s RAPTOR program. The intent of the study is to answer two questions: (1) What are the typical transmission levels of clouds as a function of target altitude for two locations and wavelengths of interest? (2) What is the probability that a cloud will intervene between sensor and target for a given target altitude, range, wavelength and location? This was addressed for Iraq and Korea. Answers to both questions are treated using existing software and data sources where possiblemore » due to the limited funding and scope of the contract.« less
Overview and future direction for blackbody solar-pumped lasers
NASA Technical Reports Server (NTRS)
Deyoung, R. J.
1988-01-01
A review of solar-pumped blackbody lasers is given which addresses their present status and suggests future research directions. The blackbody laser concept is one system proposed to scale to multimegawatt power levels for space-to-space power transmissions for such applications as onboard spacecraft electrical or propulsion needs. Among the critical technical issues are the scalability to high powers and the laser wavelength which impacts the transmission optics size as well as the laser-to-electric converter at the receiver. Because present blackbody solar-pumped lasers will have laser wavelengths longer than 4 microns, simple photovoltaic converters cannot be used, and transmission optics will be large. Thus, future blackbody laser systems should emphasize near visible laser wavelengths.
2008-01-01
information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD...microscopy ( AEM ), to characterize a variety of III-V semiconductor thin films. The materials investigated include superlattices based on the InAs- GaSb...technique. TEM observations were performed using a Philips-CM 200 FEG transmission electron microscope equipped with a field emission gun, operated at an
Reciprocity relations in transmission electron microscopy: A rigorous derivation.
Krause, Florian F; Rosenauer, Andreas
2017-01-01
A concise derivation of the principle of reciprocity applied to realistic transmission electron microscopy setups is presented making use of the multislice formalism. The equivalence of images acquired in conventional and scanning mode is thereby rigorously shown. The conditions for the applicability of the found reciprocity relations is discussed. Furthermore the positions of apertures in relation to the corresponding lenses are considered, a subject which scarcely has been addressed in previous publications. Copyright © 2016 Elsevier Ltd. All rights reserved.
Solar Occultation Retrieval Algorithm Development
NASA Technical Reports Server (NTRS)
Lumpe, Jerry D.
2004-01-01
This effort addresses the comparison and validation of currently operational solar occultation retrieval algorithms, and the development of generalized algorithms for future application to multiple platforms. initial development of generalized forward model algorithms capable of simulating transmission data from of the POAM II/III and SAGE II/III instruments. Work in the 2" quarter will focus on: completion of forward model algorithms, including accurate spectral characteristics for all instruments, and comparison of simulated transmission data with actual level 1 instrument data for specific occultation events.
Reh, Lucia; Magnus, Carsten; Schanz, Merle; Weber, Jacqueline; Uhr, Therese; Rusert, Peter; Trkola, Alexandra
2015-01-01
An increasing number of broadly neutralizing antibodies (bnAbs) are considered leads for HIV-1 vaccine development and novel therapeutics. Here, we systematically explored the capacity of bnAbs to neutralize HIV-1 prior to and post-CD4 engagement and to block HIV-1 cell-cell transmission. Cell-cell spread is known to promote a highly efficient infection with HIV-1 which can inflict dramatic losses in neutralization potency compared to free virus infection. Selection of bnAbs that are capable of suppressing HIV irrespective of the transmission mode therefore needs to be considered to ascertain their in vivo activity in therapeutic use and vaccines. Employing assay systems that allow for unambiguous discrimination between free virus and cell-cell transmission to T cells, we probed a panel of 16 bnAbs for their activity against 11 viruses from subtypes A, B and C during both transmission modes. Over a wide range of bnAb-virus combinations tested, inhibitory activity against HIV-1 cell-cell transmission was strongly decreased compared to free virus transmission. Activity loss varied considerably between virus strains and was inversely associated with neutralization of free virus spread for V1V2- and V3-directed bnAbs. In rare bnAb-virus combinations, inhibition for both transmission modes was comparable but no bnAb potently blocked cell-cell transmission across all probed virus strains. Mathematical analysis indicated an increased probability of bnAb resistance mutations to arise in cell-cell rather than free virus spread, further highlighting the need to block this pathway. Importantly, the capacity to efficiently neutralize prior to CD4 engagement correlated with the inhibition efficacy against free virus but not cell-cell transmitted virus. Pre-CD4 attachment activity proved strongest amongst CD4bs bnAbs and varied substantially for V3 and V1V2 loop bnAbs in a strain-dependent manner. In summary, bnAb activity against divergent viruses varied depending on the transmission mode and differed depending on the window of action during the entry process, underscoring that powerful combinations of bnAbs are needed for in vivo application. PMID:26158270
Household transmission of SARS, 2003
Wilson-Clark, Samantha D.; Deeks, Shelley L.; Gournis, Effie; Hay, Karen; Bondy, Susan; Kennedy, Erin; Johnson, Ian; Rea, Elizabeth; Kuschak, Theodore; Green, Diane; Abbas, Zahid; Guarda, Brenda
2006-01-01
Background In the 2003 outbreak in Toronto (in Ontario, Canada) of severe acute respiratory syndrome (SARS), about 20% of cases resulted from household transmission. The purpose of our study was to determine characteristics associated with the transmission of SARS within households. Methods A retrospective cohort of SARS-affected households was studied to determine risk factors for household transmission. Questionnaires addressed characteristics of the index case, the household and behaviours among household members. Potential risk factors for secondary transmission of infection were assessed in regression models appropriate to the outcome (secondary cases) and nonindependence of household members. Results The 74 households that participated included 18 secondary cases and 158 uninfected household members in addition to the 74 index cases. The household secondary attack rate was 10.2% (95% confidence interval [CI] 6.7%–23.5%). There was a linear association between the time the index patient spent at home after symptom onset and the secondary attack rate. Infected health care workers who were index cases had lower rates of household transmission. Interpretation SARS transmission in households is complex and increases with the length of time an ill person spends at home. Risk of transmission was lower when the index case was a health care worker. Rapid case identification is the public health measure most useful in minimizing exposure in the home. PMID:17098951
Alvarez-Ordóñez, Avelino; Martínez-Lobo, Francisco Javier; Arguello, Héctor; Carvajal, Ana; Rubio, Pedro
2013-05-10
Swine Dysentery (SD) is a severe mucohaemorhagic enteric disease of pigs caused by Brachyspira hyodysenteriae, which has a large impact on pig production and causes important losses due to mortality and sub-optimal performance. Although B. hyodysenteriae has been traditionally considered a pathogen mainly transmitted by direct contact, through the introduction of subclinically infected animals into a previously uninfected herd, recent findings position B. hyodysenteriae as a potential threat for indirect transmission between farms. This article summarizes the knowledge available on the etiological agent of SD and its virulence traits, and reviews the determinants of SD transmission. The between-herds and within-herd transmission routes are addressed. The factors affecting disease transmission are thoroughly discussed, i.e., environmental survival of the pathogen, husbandry factors (production system, production stage, farm management), role of vectors, diet influence and interaction of the microorganism with gut microbiota. Finally, prophylactic and therapeutic approaches to fight against the disease are briefly described.
Alvarez-Ordóñez, Avelino; Martínez-Lobo, Francisco Javier; Arguello, Héctor; Carvajal, Ana; Rubio, Pedro
2013-01-01
Swine Dysentery (SD) is a severe mucohaemorhagic enteric disease of pigs caused by Brachyspira hyodysenteriae, which has a large impact on pig production and causes important losses due to mortality and sub-optimal performance. Although B. hyodysenteriae has been traditionally considered a pathogen mainly transmitted by direct contact, through the introduction of subclinically infected animals into a previously uninfected herd, recent findings position B. hyodysenteriae as a potential threat for indirect transmission between farms. This article summarizes the knowledge available on the etiological agent of SD and its virulence traits, and reviews the determinants of SD transmission. The between-herds and within-herd transmission routes are addressed. The factors affecting disease transmission are thoroughly discussed, i.e., environmental survival of the pathogen, husbandry factors (production system, production stage, farm management), role of vectors, diet influence and interaction of the microorganism with gut microbiota. Finally, prophylactic and therapeutic approaches to fight against the disease are briefly described. PMID:23665849
Turk, Teja; Bachmann, Nadine; Kadelka, Claus; Böni, Jürg; Yerly, Sabine; Aubert, Vincent; Klimkait, Thomas; Battegay, Manuel; Bernasconi, Enos; Calmy, Alexandra; Cavassini, Matthias; Furrer, Hansjakob; Hoffmann, Matthias; Aubert, V; Battegay, M; Bernasconi, E; Böni, J; Braun, DL; Bucher, HC; Calmy, A; Cavassini, M; Ciuffi, A; Dollenmaier, G; Egger, M; Elzi, L; Fehr, J; Fellay, J; Furrer, H; Fux, CA; Günthard, HF; Haerry, D; Hasse, B; Hirsch, HH; Hoffmann, M; Hösli, I; Kahlert, C; Kaiser, L; Keiser, O; Klimkait, T; Kouyos, RD; Kovari, H; Ledergerber, B; Martinetti, G; Martinez de Tejada, B; Marzolini, C; Metzner, KJ; Müller, N; Nicca, D; Pantaleo, G; Paioni, P; Rauch, A; Rudin, C; Scherrer, AU; Schmid, P; Speck, R; Stöckle, M; Tarr, P; Trkola, A; Vernazza, P; Wandeler, G; Weber, R; Yerly, S
2017-01-01
Assessing the danger of transition of HIV transmission from a concentrated to a generalized epidemic is of major importance for public health. In this study, we develop a phylogeny-based statistical approach to address this question. As a case study, we use this to investigate the trends and determinants of HIV transmission among Swiss heterosexuals. We extract the corresponding transmission clusters from a phylogenetic tree. To capture the incomplete sampling, the delayed introduction of imported infections to Switzerland, and potential factors associated with basic reproductive number R0, we extend the branching process model to infer transmission parameters. Overall, the R0 is estimated to be 0.44 (95%-confidence interval 0.42—0.46) and it is decreasing by 11% per 10 years (4%—17%). Our findings indicate rather diminishing HIV transmission among Swiss heterosexuals far below the epidemic threshold. Generally, our approach allows to assess the danger of self-sustained epidemics from any viral sequence data. PMID:28895527
Epidemiology of Plasmodium vivax Malaria in Peru.
Rosas-Aguirre, Angel; Gamboa, Dionicia; Manrique, Paulo; Conn, Jan E; Moreno, Marta; Lescano, Andres G; Sanchez, Juan F; Rodriguez, Hugo; Silva, Hermann; Llanos-Cuentas, Alejandro; Vinetz, Joseph M
2016-12-28
Malaria in Peru, dominated by Plasmodium vivax, remains a public health problem. The 1990s saw newly epidemic malaria emerge, primarily in the Loreto Department in the Amazon region, including areas near to Iquitos, the capital city, but sporadic malaria transmission also occurred in the 1990s-2000s in both north-coastal Peru and the gold mining regions of southeastern Peru. Although a Global Fund-supported intervention (PAMAFRO, 2005-2010) was temporally associated with a decrease of malaria transmission, from 2012 to the present, both P. vivax and Plasmodium falciparum malaria cases have rapidly increased. The Peruvian Ministry of Health continues to provide artemesinin-based combination therapy for microscopy-confirmed cases of P. falciparum and chloroquine-primaquine for P. vivax Malaria transmission continues in remote areas nonetheless, where the mobility of humans and parasites facilitates continued reintroduction outside of ongoing surveillance activities, which is critical to address for future malaria control and elimination efforts. Ongoing P. vivax research gaps in Peru include the following: identification of asymptomatic parasitemics, quantification of the contribution of patent and subpatent parasitemics to mosquito transmission, diagnosis of nonparasitemic hypnozoite carriers, and implementation of surveillance for potential emergence of chloroquine- and 8-aminoquinoline-resistant P. vivax Clinical trials of tafenoquine in Peru have been promising, and glucose-6-phosphate dehydrogenase deficiency in the region has not been observed to be a limitation to its use. Larger-scale challenges for P. vivax (and malaria in general) in Peru include logistical difficulties in accessing remote riverine populations, consequences of government policy and poverty trends, and obtaining international funding for malaria control and elimination. © The American Society of Tropical Medicine and Hygiene.
Contact tracing of tuberculosis: a systematic review of transmission modelling studies.
Begun, Matt; Newall, Anthony T; Marks, Guy B; Wood, James G
2013-01-01
The WHO recommended intervention of Directly Observed Treatment, Short-course (DOTS) appears to have been less successful than expected in reducing the burden of TB in some high prevalence settings. One strategy for enhancing DOTS is incorporating active case-finding through screening contacts of TB patients as widely used in low-prevalence settings. Predictive models that incorporate population-level effects on transmission provide one means of predicting impacts of such interventions. We aim to identify all TB transmission modelling studies addressing contact tracing and to describe and critically assess their modelling assumptions, parameter choices and relevance to policy. We searched MEDLINE, SCOPUS, COMPENDEX, Google Scholar and Web of Science databases for relevant English language publications up to February 2012. Of the 1285 studies identified, only 5 studies met our inclusion criteria of models of TB transmission dynamics in human populations designed to incorporate contact tracing as an intervention. Detailed implementation of contact processes was only present in two studies, while only one study presented a model for a high prevalence, developing world setting. Some use of relevant data for parameter estimation was made in each study however validation of the predicted impact of interventions was not attempted in any of the studies. Despite a large body of literature on TB transmission modelling, few published studies incorporate contact tracing. There is considerable scope for future analyses to make better use of data and to apply individual based models to facilitate more realistic patterns of infectious contact. Combined with a focus on high burden settings this would greatly increase the potential for models to inform the use of contract tracing as a TB control policy. Our findings highlight the potential for collaborative work between clinicians, epidemiologists and modellers to gather data required to enhance model development and validation and hence better inform future public health policy.
Contact Tracing of Tuberculosis: A Systematic Review of Transmission Modelling Studies
Begun, Matt; Newall, Anthony T.; Marks, Guy B.; Wood, James G.
2013-01-01
The WHO recommended intervention of Directly Observed Treatment, Short-course (DOTS) appears to have been less successful than expected in reducing the burden of TB in some high prevalence settings. One strategy for enhancing DOTS is incorporating active case-finding through screening contacts of TB patients as widely used in low-prevalence settings. Predictive models that incorporate population-level effects on transmission provide one means of predicting impacts of such interventions. We aim to identify all TB transmission modelling studies addressing contact tracing and to describe and critically assess their modelling assumptions, parameter choices and relevance to policy. We searched MEDLINE, SCOPUS, COMPENDEX, Google Scholar and Web of Science databases for relevant English language publications up to February 2012. Of the 1285 studies identified, only 5 studies met our inclusion criteria of models of TB transmission dynamics in human populations designed to incorporate contact tracing as an intervention. Detailed implementation of contact processes was only present in two studies, while only one study presented a model for a high prevalence, developing world setting. Some use of relevant data for parameter estimation was made in each study however validation of the predicted impact of interventions was not attempted in any of the studies. Despite a large body of literature on TB transmission modelling, few published studies incorporate contact tracing. There is considerable scope for future analyses to make better use of data and to apply individual based models to facilitate more realistic patterns of infectious contact. Combined with a focus on high burden settings this would greatly increase the potential for models to inform the use of contract tracing as a TB control policy. Our findings highlight the potential for collaborative work between clinicians, epidemiologists and modellers to gather data required to enhance model development and validation and hence better inform future public health policy. PMID:24023742
STS-88 Endeavour: TCDT-Press Q & A at KSCNF Auditorium
NASA Technical Reports Server (NTRS)
1998-01-01
Live footage of the (Terminal Countdown Demonstration Test) TCDT shows the crew of STS-88, Commander Robert D. Cabana, Pilot Frederick W. Sturckow, and Mission Specialists Nancy J. Curry, Jerry L. Ross, James H. Newman, and Sergei K. Krikalev, participating in a press conference. The moderator Bruce Buckingham is seen introducing Bob Cabana, who then introduces the rest of the crewmembers. Cabana explains the mission and addresses the flight day activities. He includes the building of the Node 1 station element to the Functional Energy Block (FGB) which will already be in orbit, and two space-walks to connect power and data transmission cables. The crewmembers took turn answering questions from both the audience and via radio communication with the Johnson Space Center.
Epidemiology of Helicobacter pylori infection.
Leja, Mārcis; Axon, Anthony; Brenner, Hermann
2016-09-01
This review of recent publications related to the epidemiology of Helicobacter pylori highlights the origin of the infection, its changing prevalence, transmission, and outcome. A number of studies have addressed the ancestor roots of the bacteria, and the first genomewide analysis of bacterial strains suggests that its coexistence with humans is more ancient than previously thought. As opposed to the generally declining prevalence of H. pylori (including China and Japan), in Sweden, the prevalence of atrophic gastritis in the young population has risen. The prevalence of the infection remains high in the indigenous populations of the Arctic regions, and reinfection rates are high. A high prevalence is permanently found in the Siberian regions of Russia as well. Several studies, some of which used multiplex serology, addressed prevalence of and risks associated with various H. pylori serotypes, thereby enabling more precise risk assessment. Transmission of H. pylori was discussed, specifically fecal-oral transmission and the use of well-water and other unpurified water. Finally, the long-term course of H. pylori infection was considered, with an estimated 89% of noncardia gastric cancer cases being attributable to the infection. © 2016 John Wiley & Sons Ltd.
Hepatitis C Virus Cell-Cell Transmission and Resistance to Direct-Acting Antiviral Agents
Heydmann, Laura; Barth, Heidi; Soulier, Eric; Habersetzer, François; Doffoël, Michel; Bukh, Jens; Patel, Arvind H.; Zeisel, Mirjam B.; Baumert, Thomas F.
2014-01-01
Hepatitis C virus (HCV) is transmitted between hepatocytes via classical cell entry but also uses direct cell-cell transfer to infect neighboring hepatocytes. Viral cell-cell transmission has been shown to play an important role in viral persistence allowing evasion from neutralizing antibodies. In contrast, the role of HCV cell-cell transmission for antiviral resistance is unknown. Aiming to address this question we investigated the phenotype of HCV strains exhibiting resistance to direct-acting antivirals (DAAs) in state-of-the-art model systems for cell-cell transmission and spread. Using HCV genotype 2 as a model virus, we show that cell-cell transmission is the main route of viral spread of DAA-resistant HCV. Cell-cell transmission of DAA-resistant viruses results in viral persistence and thus hampers viral eradication. We also show that blocking cell-cell transmission using host-targeting entry inhibitors (HTEIs) was highly effective in inhibiting viral dissemination of resistant genotype 2 viruses. Combining HTEIs with DAAs prevented antiviral resistance and led to rapid elimination of the virus in cell culture model. In conclusion, our work provides evidence that cell-cell transmission plays an important role in dissemination and maintenance of resistant variants in cell culture models. Blocking virus cell-cell transmission prevents emergence of drug resistance in persistent viral infection including resistance to HCV DAAs. PMID:24830295
High-Throughput Assay and Discovery of Small Molecules that Interrupt Malaria Transmission
Plouffe, David M.; Wree, Melanie; Du, Alan Y.; Meister, Stephan; Li, Fengwu; Patra, Kailash; Lubar, Aristea; Okitsu, Shinji L.; Flannery, Erika L.; Kato, Nobutaka; Tanaseichuk, Olga; Comer, Eamon; Zhou, Bin; Kuhen, Kelli; Zhou, Yingyao; Leroy, Didier; Schreiber, Stuart L.; Scherer, Christina A.; Vinetz, Joseph; Winzeler, Elizabeth A.
2016-01-01
Summary Preventing transmission is an important element of malaria control. However, most of the current available methods to assay for malaria transmission blocking are relatively low throughput and cannot be applied to large chemical libraries. We have developed a high-throughput and cost-effective assay, the Saponin-lysis Sexual Stage Assay (SaLSSA), for identifying small molecules with transmission-blocking capacity. SaLSSA analysis of 13,983 unique compounds uncovered that >90% of well-characterized antimalarials, including endoperoxides and 4-aminoquinolines, as well as compounds active against asexual blood stages, lost most of their killing activity when parasites developed into metabolically quiescent stage V gametocytes. On the other hand, we identified compounds with consistent low nanomolar transmission-blocking activity, some of which showed cross-reactivity against asexual blood and liver stages. The data clearly emphasize substantial physiological differences between sexual and asexual parasites and provide a tool and starting points for the discovery and development of transmission-blocking drugs. PMID:26749441
Ethnic and cultural determinants influence risk assessment for hepatitis C acquisition.
Dev, Anouk; Sundararajan, Vijaya; Sievert, William
2004-07-01
In the developed world hepatitis C virus (HCV) infection is predominantly associated with sharing contaminated equipment between injecting drug users (IDU). In developing countries inadequately sterilized medical equipment, transmission of infected blood and cultural practices have been implicated. Accurate risk factor assessment is essential for education targeted at risk reduction in culturally diverse populations. Ninety Australian-born Caucasians and 72 South-east Asian (SEA) HCV patients attending a Melbourne hospital liver clinic completed a questionnaire which assessed risk factor profile, perceived risk factors, knowledge of risk factors and methods to minimize transmission. Medical records were audited to identify doctor assessment of risk factors. Risk factors in Caucasians were IDU, body piercing and tattooing (89%, 47% and 32%, respectively). Risk factors in SEA patients were injection therapy, dental therapy and surgery (89%, 70% and 38%, respectively). Most Caucasian patients (94%) correctly identified their mode of acquisition compared with 33% of SEA patients (P < 0.0001). Accurate risk factor documentation in medical records was more common in Caucasians (96 vs 32%; P < 0.0001). The majority of patients identified blood-to-blood and sexual/vertical transmission as important modes of acquisition. However, 33% of SEA patients believed transmission occurred through food, water and poor hygiene and 80% did not identify therapeutic injection or traditional medical practices as risk factors. Education provided to SEA patients did not address less well established routes of transmission. Ethnicity influences perception and knowledge of risk factors. Improved assessment of risk factors in high-risk ethnic groups is needed. Education should be culturally appropriate and address the concerns of all populations with HCV. Copyright 2004 Blackwell Publishing Asia Pty Ltd
NASA Astrophysics Data System (ADS)
Cole, Michael A.; Chen, Wen-chen; Liu, Mingkai; Kruk, Sergey S.; Padilla, Willie J.; Shadrivov, Ilya V.; Powell, David A.
2017-07-01
We demonstrate terahertz chiral metamaterials that achieve resonant transmission and strong optical activity. This response is realized in a metasurface coupled to its Babinet complement, with additional twist. Uniquely, the optical activity achieved in this type of metamaterial is weakly dispersive around the resonant transmission maxima, but it can be highly dispersive around the transmission minima. It has recently been shown that this unique optical activity response is closely related to zeros in the transmission spectra of circular polarizations through the Kramers-Kronig relations and strong resonant features in the optical activity spectrum corresponding to the Blaschke phase terms. Here we demonstrate how modifying the meta-atom geometry greatly affects the location and magnitude of these Blaschke phase terms. We study three different meta-atoms, which are variations on the simple cross structure. Their responses are measured using terahertz time-domain spectroscopy and analyzed via numerical simulations.
Exploring the optical contrast effect in strong atomic lines for exoplanets transiting active stars
NASA Astrophysics Data System (ADS)
Cauley, Paul W.; Redfield, Seth
2017-01-01
Transmission spectroscopy is a powerful tool for detecting and characterizing planetary atmospheres. Non-photospheric features on the stellar disk, however, can contaminate the planetary signal: during transit the observed spectrum is weighted towards the features not currently being occulted by the planet. This contrast effect can mimic absorption in the planetary atmosphere for strong atomic lines such as Na I, Ca II, and the hydrogen Balmer lines. While the contrast effect is negligible for quiet stars, contributions to the transmission signal from active stellar surfaces can produce ~1% changes in the line core. It is therefore critical that these contrast signals be differentiated from true absorption features in the planetary atmosphere. Here we present our work on simulating the contrast effect for an active stellar surface. We discuss the particular case of HD 189733 b, a well-studied hot Jupiter orbiting an active K-dwarf, due to the plethora of atomic absorption signals reported in its atmosphere.Specifically, we focus on Hα to address recent suggestions that the measured in-transit signals are a result of stellar activity. In the contrast model we include center-to-limb variations and calculate limb darkening parameters as a function of wavelength across the line of interest. The model includes contributions to the spectrum from spots, faculae and plages, filaments, and the bare stellar photosphere. Stellar rotation is also included. We find that it is very difficult to reproduce the measured in-transit Hα signals for reasonable active region parameters. In addition, it is difficult to create an in-transit contrast signature that lasts for the duration of the transit unless the planet is crossing an active latitudinal belt and is always obscuring active regions. This suggests that the Hα measurements arise predominantly in the planetary atmosphere. However, the contrast effect likely contributes to these signals. Furthermore, our results could be modified if the active regions of HD 189733 b have drastically different characteristics than solar active regions. Further observations of transits across active stars will aid in disentangling the planetary signals from the stellar.
Microwave Power Transmission Using Electromagnetic Coupling of Open-Ring Resonators
2012-11-01
AUTHOR(S) Yasuo Ohno 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) The University...of Tokushima,2-1 Minami-Josanjima-cho,Tokushima-shi 770-8506,Japan,JP,770-8506 8. PERFORMING ORGANIZATION REPORT NUMBER N/A 9. SPONSORING...efficiency, the reduction of ON-resistance (RON) and OFF-capacitance ( COFF ) is essential. For power rectification, the voltage applicable to the
Time/Frequency Relationships for an FFT-Based Acoustic Modem
2010-09-01
Jenkins II 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING... seawater , and a fluid- like bottom composed of quartz sand. From [11] ............................................18 Table 3. Transmission loss at the...in St. Andrew’s Bay, Florida [4]. The goal of this sea testing was to observe the effects of natural and man-made noise on network performance in a
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-27
... occur when comparing the original testing (use of switching impulses and corona free electrodes) against... vegetation instead of corona-free electrodes? Do the equations adequately address the limiting conditions (i...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weller, R.E.
An overview is provided for veterinary care of urogenital tumors in companion animals, especially the dog. Neoplasms discussed include tumors of the kidney, urinary bladder, prostate, testis, ovary, vagina, vulva and the canine transmissible venereal tumor. Topics addressed include description, diagnosis and treatment.
Addressing Institutional Amplifiers in the Dynamics and Control of Tuberculosis Epidemics
Basu, Sanjay; Stuckler, David; McKee, Martin
2011-01-01
Tuberculosis outbreaks originating in prisons, mines, or hospital wards can spread to the larger community. Recent proposals have targeted these high-transmission institutional amplifiers by improving case detection, treatment, or reducing the size of the exposed population. However, what effects these alternative proposals may have is unclear. We mathematically modeled these control strategies and found case detection and treatment methods insufficient in addressing epidemics involving common types of institutional amplifiers. Movement of persons in and out of amplifiers fundamentally altered the transmission dynamics of tuberculosis in a manner not effectively mitigated by detection or treatment alone. Policies increasing the population size exposed to amplifiers or the per-person duration of exposure within amplifiers potentially worsened incidence, even in settings with high rates of detection and treatment success. However, reducing the total population size entering institutional amplifiers significantly lowered tuberculosis incidence and the risk of propagating new drug-resistant tuberculosis strains. PMID:21212197
Parallel Excitation for B-Field Insensitive Fat-Saturation Preparation
Heilman, Jeremiah A.; Derakhshan, Jamal D.; Riffe, Matthew J.; Gudino, Natalia; Tkach, Jean; Flask, Chris A.; Duerk, Jeffrey L.; Griswold, Mark A.
2016-01-01
Multichannel transmission has the potential to improve many aspects of MRI through a new paradigm in excitation. In this study, multichannel transmission is used to address the effects that variations in B0 homogeneity have on fat-saturation preparation through the use of the frequency, phase, and amplitude degrees of freedom afforded by independent transmission channels. B1 homogeneity is intrinsically included via use of coil sensitivities in calculations. A new method, parallel excitation for B-field insensitive fat-saturation preparation, can achieve fat saturation in 89% of voxels with Mz ≤ 0.1 in the presence of ±4 ppm B0 variation, where traditional CHESS methods achieve only 40% in the same conditions. While there has been much progress to apply multichannel transmission at high field strengths, particular focus is given here to application of these methods at 1.5 T. PMID:22247080
Barbaro, Nicole; Boutwell, Brian B; Barnes, J C; Shackelford, Todd K
2017-01-01
Traditional attachment theory posits that attachment in infancy and early childhood is the result of intergenerational transmission of attachment from parents to offspring. Verhage et al. (2016) present meta-analytic evidence addressing the intergenerational transmission of attachment between caregivers and young children. In this commentary, we argue that their appraisal of the behavioral genetics literature is incomplete. The suggested research focus on shared environmental effects may dissuade the pursuit of profitable avenues of research and may hinder progress in attachment theory. Specifically, further research on the "transmission gap" will continue to limit our understanding of attachment etiology. We discuss recent theoretical developments from an evolutionary psychological perspective that can provide a valuable framework to account for the existing behavioral genetic data. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Design and control of electromagnetic clutch actuation system for automated manual transmission
NASA Astrophysics Data System (ADS)
Ranjan, Ashish; Prasanth, S.; Cherian, Fenin; Baskar, P.
2017-11-01
There is a growing interest towards Automatic Transmission in India as it provides better comfort and drivability. But the high cost of this system is limiting itself to be successful in the Indian markets. Due to this, Automated Manual Transmission (AMT) is considered which provides a better solution towards automation as it enhances the drivability and fuel consumption characteristics of a manual transmission at lower costs. However, torque lag and comfort are major issues with AMT which can be addressed by reducing the shift time. In this paper we describe an Electromagnetic Linear Clutch Actuator as a replacement to current electrohydraulic and electromechanical actuator. A control system for the actuator is presented and a clutch engagement strategy is also implemented which reduces the engagement time to 0.78 seconds while reducing jerk and torque lag. The actuator and control system is simulated on a MATLAB Simulink and agreeable results have been obtained.
Low-power low-latency MAC protocol for aeronautical applications
NASA Astrophysics Data System (ADS)
Sabater, Jordi; Kluge, Martin; Bovelli, Sergio; Schalk, Josef
2007-05-01
This paper describes asynchronous MAC (Medium Access Control) strategies based on the IEEE 802.15.4 physical layer for wireless aeronautical applications where low power and low latency are important requirements as well as security and data integrity. Sensor data is acquired and collected on request, by means of a mobile device, and later stored in a centralized database. In order to have the smallest power consumption the wireless sensor has to remain in deep sleep mode as long as possible and wake up and listen periodically for RF activity. If its unique ID is mentioned in the destination address field, the complete frame is received, processed and replied if necessary. If the detected packet is addressed to another sensor the reception will stop immediately and the wireless sensor will go into deep sleep mode again. Listening instead of sending actively does not 'pollute' the already crowded 2.45GHz spectrum, reduces collisions and increases security. The mobile data concentrator can not be synchronized with all the sensors installed in a distributed environment, therefore smart asynchronous data transmission strategies are needed to reduce latencies and increase throughput. For the considered application, sensors are independent of each other, simply share the medium and together with the data concentrator are organized in a star network topology. The centre of the star is the concentrator which is rarely in range. It coordinates and activates the wireless sensor nodes to collect the measured data.
Machine learning for epigenetics and future medical applications
Holder, Lawrence B.; Haque, M. Muksitul; Skinner, Michael K.
2017-01-01
ABSTRACT Understanding epigenetic processes holds immense promise for medical applications. Advances in Machine Learning (ML) are critical to realize this promise. Previous studies used epigenetic data sets associated with the germline transmission of epigenetic transgenerational inheritance of disease and novel ML approaches to predict genome-wide locations of critical epimutations. A combination of Active Learning (ACL) and Imbalanced Class Learning (ICL) was used to address past problems with ML to develop a more efficient feature selection process and address the imbalance problem in all genomic data sets. The power of this novel ML approach and our ability to predict epigenetic phenomena and associated disease is suggested. The current approach requires extensive computation of features over the genome. A promising new approach is to introduce Deep Learning (DL) for the generation and simultaneous computation of novel genomic features tuned to the classification task. This approach can be used with any genomic or biological data set applied to medicine. The application of molecular epigenetic data in advanced machine learning analysis to medicine is the focus of this review. PMID:28524769
Progress toward interruption of wild poliovirus transmission - worldwide, 2009.
2010-05-14
In 1988, an estimated 350,000 cases of poliomyelitis were occurring annually worldwide. By 2005, because of global vaccination efforts, indigenous transmission of wild poliovirus (WPV) types 1 and 3 (WPV1 and WPV3) had been eliminated from all but four countries (Afghanistan, India, Nigeria, and Pakistan). No cases of WPV type 2 have been reported since 1999. This report describes progress toward global WPV eradication during 2009 and updates previous reports. During 2009 a total of 1,606 cases of WPV infection were reported, compared with 1,651 in 2008. WPV3 incidence increased 67%, to 1,124 cases, compared with 675 in 2008. However, WPV1 incidence decreased 51%, to 482 cases in 2009, compared with 976 cases in 2008. In India, nearly all polio cases in 2009 were reported in high-risk districts in western Uttar Pradesh and central Bihar. In Afghanistan and Pakistan, WPV circulation in high-risk districts continued because of difficulties vaccinating children in conflict-affected areas and operational limitations in parts of Pakistan. In Nigeria, cases decreased by 51%, to 388 cases in 2009, compared with 798 in 2008. During 2009, outbreaks from importation of WPV affected 19 previously polio-free African countries. Two key steps are needed to make further progress in polio eradication: 1) addressing local barriers to interrupting transmission, and 2) using bivalent oral poliovirus vaccine (bOPV) broadly for WPV 1 and 3 in supplemental immunization activities (SIAs).
Design of a novel, one-sided, pedal-activated wheelchair.
Lin, T-Y; Hsiao, K-H; Yao, H-W
2011-07-01
The present paper proposes the design of a novel, one-sided, pedal-activated wheelchair for patients with hemiplegia or hemiparesis. The design comprises a planetary hub transmission, which is embedded in the hub of the wheelchair, with drive, neutral, and reverse modes. The paper first discusses the structural characteristics and motion transmission of the wheelchair, and then presents the motion design of the hub transmission, followed by assembly and testing of the prototype. The results confirm that the proposed wheelchair and hub transmission can meet users' demands, thus improving comfort and independence.
NASA Astrophysics Data System (ADS)
Panin, V. Y.; Aykac, M.; Casey, M. E.
2013-06-01
The simultaneous PET data reconstruction of emission activity and attenuation coefficient distribution is presented, where the attenuation image is constrained by exploiting an external transmission source. Data are acquired in time-of-flight (TOF) mode, allowing in principle for separation of emission and transmission data. Nevertheless, here all data are reconstructed at once, eliminating the need to trace the position of the transmission source in sinogram space. Contamination of emission data by the transmission source and vice versa is naturally modeled. Attenuated emission activity data also provide additional information about object attenuation coefficient values. The algorithm alternates between attenuation and emission activity image updates. We also proposed a method of estimation of spatial scatter distribution from the transmission source by incorporating knowledge about the expected range of attenuation map values. The reconstruction of experimental data from the Siemens mCT scanner suggests that simultaneous reconstruction improves attenuation map image quality, as compared to when data are separated. In the presented example, the attenuation map image noise was reduced and non-uniformity artifacts that occurred due to scatter estimation were suppressed. On the other hand, the use of transmission data stabilizes attenuation coefficient distribution reconstruction from TOF emission data alone. The example of improving emission images by refining a CT-based patient attenuation map is presented, revealing potential benefits of simultaneous CT and PET data reconstruction.
Koenig, Linda J; Nesheim, Steven; Abramowitz, Susan
2011-10-01
Because of widespread availability of highly active antiretroviral therapy in the developed world, a large proportion of children with perinatally acquired HIV have survived to adolescence and young adulthood. Although their survival is remarkable, many now experience the long-term effects of HIV infection and its treatment. Further, as these youths have entered adolescence, more is known about the impact of normative developmental transitions on health maintenance behaviors. Although perinatally infected adolescents are healthier than they were a decade or more ago, they are significantly experienced with antiretroviral therapy, with increased virological resistance and other consequences of extended antiretroviral use. Three behavioral health challenges have been documented in the first cohort of long-term survivors: decreased medication adherence, sexual debut and accompanying pregnancy and transmission risk, and mental health problems. These issues are consistent with a developmental press for autonomy, mature sexual relationships and future planning, but must be carefully managed to preserve health. Adolescents with perinatally acquired HIV require coordinated multidisciplinary support services - including adherence support, reproductive health counseling addressing both pregnancy planning and disease transmission, and mental health and educational/vocational planning - so that they can fully benefit from treatment advances. (C) 2011 Lippincott Williams & Wilkins, Inc.
2014-01-01
Background Non-pharmaceutical public health interventions may provide simple, low-cost, effective ways of minimising the transmission and impact of acute respiratory infections in pandemic and non-pandemic contexts. Understanding what influences the uptake of non-pharmaceutical interventions such as hand and respiratory hygiene, mask wearing and social distancing could help to inform the development of effective public health advice messages. The aim of this synthesis was to explore public perceptions of non-pharmaceutical interventions that aim to reduce the transmission of acute respiratory infections. Methods Five online databases (MEDLINE, PsycINFO, CINAHL, EMBASE and Web of Science) were systematically searched. Reference lists of articles were also examined. We selected papers that used a qualitative research design to explore perceptions and beliefs about non-pharmaceutical interventions to reduce transmission of acute respiratory infections. We excluded papers that only explored how health professionals or children viewed non-pharmaceutical respiratory infection control. Three authors performed data extraction and assessment of study quality. Thematic analysis and components of meta-ethnography were adopted to synthesise findings. Results Seventeen articles from 16 studies in 9 countries were identified and reviewed. Seven key themes were identified: perceived benefits of non-pharmaceutical interventions, perceived disadvantages of non-pharmaceutical interventions, personal and cultural beliefs about infection transmission, diagnostic uncertainty in emerging respiratory infections, perceived vulnerability to infection, anxiety about emerging respiratory infections and communications about emerging respiratory infections. The synthesis showed that some aspects of non-pharmaceutical respiratory infection control (particularly hand and respiratory hygiene) were viewed as familiar and socially responsible actions to take. There was ambivalence about adopting isolation and personal distancing behaviours in some contexts due to their perceived adverse impact and potential to attract social stigma. Common perceived barriers included beliefs about infection transmission, personal vulnerability to respiratory infection and concerns about self-diagnosis in emerging respiratory infections. Conclusions People actively evaluate non-pharmaceutical interventions in terms of their perceived necessity, efficacy, acceptability, and feasibility. To enhance uptake, it will be necessary to address key barriers, such as beliefs about infection transmission, rejection of personal risk of infection and concern about the potential costs and stigma associated with some interventions. PMID:24920395
When are pathogen genome sequences informative of transmission events?
Ferguson, Neil; Jombart, Thibaut
2018-01-01
Recent years have seen the development of numerous methodologies for reconstructing transmission trees in infectious disease outbreaks from densely sampled whole genome sequence data. However, a fundamental and as of yet poorly addressed limitation of such approaches is the requirement for genetic diversity to arise on epidemiological timescales. Specifically, the position of infected individuals in a transmission tree can only be resolved by genetic data if mutations have accumulated between the sampled pathogen genomes. To quantify and compare the useful genetic diversity expected from genetic data in different pathogen outbreaks, we introduce here the concept of ‘transmission divergence’, defined as the number of mutations separating whole genome sequences sampled from transmission pairs. Using parameter values obtained by literature review, we simulate outbreak scenarios alongside sequence evolution using two models described in the literature to describe transmission divergence of ten major outbreak-causing pathogens. We find that while mean values vary significantly between the pathogens considered, their transmission divergence is generally very low, with many outbreaks characterised by large numbers of genetically identical transmission pairs. We describe the impact of transmission divergence on our ability to reconstruct outbreaks using two outbreak reconstruction tools, the R packages outbreaker and phybreak, and demonstrate that, in agreement with previous observations, genetic sequence data of rapidly evolving pathogens such as RNA viruses can provide valuable information on individual transmission events. Conversely, sequence data of pathogens with lower mean transmission divergence, including Streptococcus pneumoniae, Shigella sonnei and Clostridium difficile, provide little to no information about individual transmission events. Our results highlight the informational limitations of genetic sequence data in certain outbreak scenarios, and demonstrate the need to expand the toolkit of outbreak reconstruction tools to integrate other types of epidemiological data. PMID:29420641
Advances in traction drive technology
NASA Technical Reports Server (NTRS)
Loewenthal, S. H.; Anderson, N. E.; Rohn, D. A.
1983-01-01
Traction drives are traced from early uses as main transmissions in automobiles at the turn of the century to modern, high-powered traction drives capable of transmitting hundreds of horsepower. Recent advances in technology are described which enable today's traction drive to be a serious candidate for off-highway vehicles and helicopter applications. Improvements in materials, traction fluids, design techniques, power loss and life prediction methods will be highlighted. Performance characteristics of the Nasvytis fixed-ratio drive are given. Promising future drive applications, such as helicopter main transmissions and servo-control positioning mechanisms are also addressed.
PRSEUS Acoustic Panel Fabrication
NASA Technical Reports Server (NTRS)
Nicolette, Velicki; Yovanof, Nicolette P.; Baraja, Jaime; Mathur, Gopal; Thrash, Patrick; Pickell, Robert
2011-01-01
This report describes the development of a novel structural concept, Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS), that addresses the demanding fuselage loading requirements for the Hybrid Wing or Blended Wing Body (BWB) airplane configuration with regards to acoustic response. A PRSEUS panel was designed and fabricated and provided to NASA-LaRC for acoustic response testing in the Structural Acoustics Loads and Transmission (SALT) facility). Preliminary assessments of the sound transmission characteristics of a PRSEUS panel subjected to a representative Hybrid Wing Body (HWB) operating environment were completed for the NASA Environmentally Responsible Aviation (ERA) Program.
The Plasmodium bottleneck: malaria parasite losses in the mosquito vector
Smith, Ryan C; Vega-Rodríguez, Joel; Jacobs-Lorena, Marcelo
2014-01-01
Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission. PMID:25185005
NASA Astrophysics Data System (ADS)
Qiao, Yaojun; Li, Ming; Yang, Qiuhong; Xu, Yanfei; Ji, Yuefeng
2015-01-01
Closed-form expressions of nonlinear interference of dense wavelength-division-multiplexed (WDM) systems with dispersion managed transmission (DMT) are derived. We carry out a simulative validation by addressing an ample and significant set of the Nyquist-WDM systems based on polarization multiplexed quadrature phase-shift keying (PM-QPSK) subcarriers at a baud rate of 32 Gbaud per channel. Simulation results show the simple closed-form analytical expressions can provide an effective tool for the quick and accurate prediction of system performance in DMT coherent optical systems.
Electricity generation and transmission planning in deregulated power markets
NASA Astrophysics Data System (ADS)
He, Yang
This dissertation addresses the long-term planning of power generation and transmission facilities in a deregulated power market. Three models with increasing complexities are developed, primarily for investment decisions in generation and transmission capacity. The models are presented in a two-stage decision context where generation and transmission capacity expansion decisions are made in the first stage, while power generation and transmission service fees are decided in the second stage. Uncertainties that exist in the second stage affect the capacity expansion decisions in the first stage. The first model assumes that the electric power market is not constrained by transmission capacity limit. The second model, which includes transmission constraints, considers the interactions between generation firms and the transmission network operator. The third model assumes that the generation and transmission sectors make capacity investment decisions separately. These models result in Nash-Cournot equilibrium among the unregulated generation firms, while the regulated transmission network operator supports the competition among generation firms. Several issues in the deregulated electric power market can be studied with these models such as market powers of generation firms and transmission network operator, uncertainties of the future market, and interactions between the generation and transmission sectors. Results deduced from the developed models include (a) regulated transmission network operator will not reserve transmission capacity to gain extra profits; instead, it will make capacity expansion decisions to support the competition in the generation sector; (b) generation firms will provide more power supplies when there is more demand; (c) in the presence of future uncertainties, the generation firms will add more generation capacity if the demand in the future power market is expected to be higher; and (d) the transmission capacity invested by the transmission network operator depends on the characteristic of the power market and the topology of the transmission network. Also, the second model, which considers interactions between generation and transmission sectors, yields higher social welfare in the electric power market, than the third model where generation firms and transmission network operator make investment decisions separately.
The Ins and Outs of Modern Doors.
ERIC Educational Resources Information Center
College Planning & Management, 1999
1999-01-01
Discusses the qualities and trends in modern metal doors for educational facilities that include fire protection and sound-control attributes. Important differences in door manufacturing methods and materials are addressed and sound-transmission class values, ratings, and rating descriptions are listed. (GR)
GPS-Like Phasing Control of the Space Solar Power System Transmission Array
NASA Technical Reports Server (NTRS)
Psiaki, Mark L.
2003-01-01
The problem of phasing of the Space Solar Power System's transmission array has been addressed by developing a GPS-like radio navigation system. The goal of this system is to provide power transmission phasing control for each node of the array that causes the power signals to add constructively at the ground reception station. The phasing control system operates in a distributed manner, which makes it practical to implement. A leader node and two radio navigation beacons are used to control the power transmission phasing of multiple follower nodes. The necessary one-way communications to the follower nodes are implemented using the RF beacon signals. The phasing control system uses differential carrier phase relative navigation/timing techniques. A special feature of the system is an integer ambiguity resolution procedure that periodically resolves carrier phase cycle count ambiguities via encoding of pseudo-random number codes on the power transmission signals. The system is capable of achieving phasing accuracies on the order of 3 mm down to 0.4 mm depending on whether the radio navigation beacons operate in the L or C bands.
Salem, Hassan; Florez, Laura; Gerardo, Nicole; Kaltenpoth, Martin
2015-01-01
Across animals and plants, numerous metabolic and defensive adaptations are a direct consequence of symbiotic associations with beneficial microbes. Explaining how these partnerships are maintained through evolutionary time remains one of the central challenges within the field of symbiosis research. While genome erosion and co-cladogenesis with the host are well-established features of symbionts exhibiting intracellular localization and transmission, the ecological and evolutionary consequences of an extracellular lifestyle have received little attention, despite a demonstrated prevalence and functional importance across many host taxa. Using insect–bacteria symbioses as a model, we highlight the diverse routes of extracellular symbiont transfer. Extracellular transmission routes are unified by the common ability of the bacterial partners to survive outside their hosts, thereby imposing different genomic, metabolic and morphological constraints than would be expected from a strictly intracellular lifestyle. We emphasize that the evolutionary implications of symbiont transmission routes (intracellular versus extracellular) do not necessarily correspond to those of the transmission mode (vertical versus horizontal), a distinction of vital significance when addressing the genomic and physiological consequences for both host and symbiont. PMID:25740892
All-optical video-image encryption with enforced security level using independent component analysis
NASA Astrophysics Data System (ADS)
Alfalou, A.; Mansour, A.
2007-10-01
In the last two decades, wireless communications have been introduced in various applications. However, the transmitted data can be, at any moment, intercepted by non-authorized people. That could explain why data encryption and secure transmission have gained enormous popularity. In order to secure data transmission, we should pay attention to two aspects: transmission rate and encryption security level. In this paper, we address these two aspects by proposing a new video-image transmission scheme. This new system consists in using the advantage of optical high transmission rate and some powerful signal processing tools to secure the transmitted data. The main idea of our approach is to secure transmitted information at two levels: at the classical level by using an adaptation of standard optical techniques and at a second level (spatial diversity) by using independent transmitters. In the second level, a hacker would need to intercept not only one channel but all of them in order to retrieve information. At the receiver, we can easily apply ICA algorithms to decrypt the received signals and retrieve information.
Vallone, Alessandra; D'Alessandro, Sarah; Brogi, Simone; Brindisi, Margherita; Chemi, Giulia; Alfano, Gloria; Lamponi, Stefania; Lee, Soon Goo; Jez, Joseph M; Koolen, Karin J M; Dechering, Koen J; Saponara, Simona; Fusi, Fabio; Gorelli, Beatrice; Taramelli, Donatella; Parapini, Silvia; Caldelari, Reto; Campiani, Giuseppe; Gemma, Sandra; Butini, Stefania
2018-04-25
Therapies addressing multiple stages of Plasmodium falciparum life cycle are highly desirable for implementing malaria elimination strategies. MMV019918 (1, 1-[5-(4-bromo-2-chlorophenyl)furan-2-yl]-N-[(piperidin-4-yl)methyl]methanamine) was selected from the MMV Malaria Box for its dual activity against both asexual stages and gametocytes. In-depth structure-activity relationship studies and cytotoxicity evaluation led to the selection of 25 for further biological investigation. The potential transmission blocking activity of 25 versus P. falciparum was confirmed through the standard membrane-feeding assay. Both 1 and 25 significantly prolonged atrioventricular conduction time in Langendorff-isolated rat hearts, and showed inhibitory activity of Ba 2+ current through Ca v 1.2 channels. An in silico target-fishing study suggested the enzyme phosphoethanolamine methyltransferase (PfPMT) as a potential target. However, compound activity against PfPMT did not track with the antiplasmodial activity, suggesting the latter activity relies on a different molecular target. Nevertheless, 25 showed interesting activity against PfPMT, which could be an important starting point for the identification of more potent inhibitors active against both sexual and asexual stages of the parasite. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Medical students' note-taking in a medical biochemistry course: an initial exploration.
Morrison, Elizabeth H; McLaughlin, Calvin; Rucker, Lloyd
2002-04-01
Beginning medical students spend numerous hours every week attending basic science lectures and taking notes. Medical faculty often wonder whether they should give students pre-printed instructors' notes before lectures. Proponents of this strategy argue that provided notes enhance learning by facilitating the accurate transmission of information, while opponents counter that provided notes inhibit students' cognitive processing or even discourage students from attending lectures. Little if any research has directly addressed medical students' note-taking or the value of providing instructors' notes. The educational literature does suggest that taking lecture notes enhances university students' learning. University students perform best on post-lecture testing if they review a combination of provided notes and their own personal notes, particularly if the provided notes follow a 'skeletal' format that encourages active note-taking.
Practical holography III; Proceedings of the Meeting, Los Angeles, CA, Jan. 17, 18, 1989
NASA Astrophysics Data System (ADS)
Benton, Stephen A.
Various papers on practical holography are presented. Individual topics addressed include: design of large format commercial display holograms, design of a one-step full-color holographic recording system, color reflection holography, full color rainbow hologram using a photoresist plate, secondary effects in processing holograms, archival properties of holograms, survey of properties of volume holographic materials, image stability of DMP-128 holograms, activation monitor for DMP-128, microwave drying effects on dichromated gelatin holograms, sensitization process of dichromated gelatin, holographic optics for vision systems, holographic fingerprint sensor, cross-talk and cross-coupling in multiplexed holographic gratings, compact illuminators for transmission holograms, solar holoconcentrators in dichromated grains, three-dimensional display of scientific data, holographic liquid crystal displays, in situ swelling for hologaphic color control.
Hybrid energy harvesting/transmission system for embedded devices
NASA Astrophysics Data System (ADS)
Hehr, Adam; Park, Gyuhae; Farinholt, Kevin
2012-04-01
In most energy harvesting applications the need for a reliable long-term energy supply is essential in powering embedded sensing and control electronics. The goal of many harvesters is to extract energy from the ambient environment to power hardware; however in some applications there may be conditions in which the harvester's performance cannot meet all of the demands of the embedded electronics. One method for addressing this shortfall is to supplement harvested power through the transmission of wireless energy, a concept that has successfully been demonstrated by the authors in previous studies. In this paper we present our findings on the use of a single electromagnetic coil to harvest kinetic energy in a solenoid configuration, as well as background and directed wireless energy in the 2.4 GHz radio frequency (RF) bands commonly used in WiFi and cellular phone applications. The motivation for this study is to develop a compact energy harvester / receiver that conserves physical volume, while providing multi-modal energy harvesting capabilities. As with most hybrid systems there are performance trade-offs that must be considered when capturing energy from different physical sources. As part of this paper, many of the issues related to power transmission, physical design, and potential applications are addressed for this device.
A Hands-On Activity to Introduce the Effects of Transmission by an Invasive Species
ERIC Educational Resources Information Center
May, Barbara Jean
2013-01-01
This activity engages students to better understand the impact of transmission by invasive species. Using dice, poker chips, and paper plates, an entire class mimics the spread of an invasive species within a geographic region. The activity can be modified and conducted at the K-16 levels.
Misol, Malte; Haase, Thomas; Monner, Hans Peter; Sinapius, Michael
2014-10-01
This paper provides experimental results of an aircraft-relevant double panel structure mounted in a sound transmission loss facility. The primary structure of the double panel system is excited either by a stochastic point force or by a diffuse sound field synthesized in the reverberation room of the transmission loss facility. The secondary structure, which is connected to the frames of the primary structure, is augmented by actuators and sensors implementing an active feedforward control system. Special emphasis is placed on the causality of the active feedforward control system and its implications on the disturbance rejection at the error sensors. The coherence of the sensor signals is analyzed for the two different disturbance excitations. Experimental results are presented regarding the causality, coherence, and disturbance rejection of the active feedforward control system. Furthermore, the sound transmission loss of the double panel system is evaluated for different configurations of the active system. A principal result of this work is the evidence that it is possible to strongly influence the transmission of stochastic disturbance sources through double panel configurations by means of an active feedforward control system.
Zheng, Li; Pang, Wei; Qi, Zanmei; Luo, Enjie; Cui, Liwang; Cao, Yaming
2016-08-08
Transmission-blocking vaccine (TBV) is a promising strategy for interrupting the malaria transmission cycle. Current TBV candidates include both pre- and post-fertilization antigens expressed during sexual development of the malaria parasites. We tested whether a TBV design combining two sexual-stage antigens has better transmission-blocking activity. Using the rodent malaria model Plasmodium yoelii, we pursued a DNA vaccination strategy with genes encoding the gametocyte antigen Pys48/45 and the major ookinete surface protein Pys25. Immunization of mice with DNA constructs expression either Pys48/45 or Pys25 elicited strong antibody responses, which specifically recognized a ~45 and ~25 kDa protein from gametocyte and ookinete lysates, respectively. Immune sera from mice immunized with DNA constructs expressing Pys48/45 and Pys25 individually and in combination displayed evident transmission-blocking activity in in vitro ookinete culture and direct mosquito feeding experiments. With both assays, the Pys25 sera had higher transmission-blocking activity than the Pys48/45 sera. Intriguingly, compared with the immunization with the individual DNA vaccines, immunization with both DNA constructs produced lower antibody responses against individual antigens. The resultant immune sera from the composite vaccination had significantly lower transmission-blocking activity than those from Pys25 DNA immunization group, albeit the activity was substantially higher than that from the Pys48 DNA vaccination group. This result suggested that vaccination with the two DNA constructs did not achieve a synergistic effect, but rather caused interference in inducing antigen-specific antibody responses. This result has important implications for future design of composite vaccines targeting different sexual antigens.
Multi-dimensional effects of color on the world wide web
NASA Astrophysics Data System (ADS)
Morton, Jill
2002-06-01
Color is the most powerful building material of visual imagery on the World Wide Web. It must function successfully as it has done historically in traditional two-dimensional media, as well as address new challenges presented by this electronic medium. The psychological, physiological, technical and aesthetic effects of color have been redefined by the unique requirements of the electronic transmission of text and images on the Web. Color simultaneously addresses each of these dimensions in this electronic medium.
2009-03-22
indirect effect (AIE) index determined from the slope of the fitted linear equation involving cloud particle size vs. aerosol optical depth is about a... raindrop . The model simulations were performed for a 48-hour period, starting at 00Z on 29 March 2007, about 20 hours prior to ABL test flight time...UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) MS. KRISTEN LUND UNIV OF CALIFORNIA LOS ANGELES, CA 90095 8. PERFORMING
NASA Astrophysics Data System (ADS)
Zheng, Ling; Duan, Xuwei; Deng, Zhaoxue; Li, Yinong
2014-03-01
A novel flow-mode magneto-rheological (MR) engine mount integrated a diaphragm de-coupler and the spoiler plate is designed and developed to isolate engine and the transmission from the chassis in a wide frequency range and overcome the stiffness in high frequency. A lumped parameter model of the MR engine mount in single degree of freedom system is further developed based on bond graph method to predict the performance of the MR engine mount accurately. The optimization mathematical model is established to minimize the total of force transmissibility over several frequency ranges addressed. In this mathematical model, the lumped parameters are considered as design variables. The maximum of force transmissibility and the corresponding frequency in low frequency range as well as individual lumped parameter are limited as constraints. The multiple interval sensitivity analysis method is developed to select the optimized variables and improve the efficiency of optimization process. An improved non-dominated sorting genetic algorithm (NSGA-II) is used to solve the multi-objective optimization problem. The synthesized distance between the individual in Pareto set and the individual in possible set in engineering is defined and calculated. A set of real design parameters is thus obtained by the internal relationship between the optimal lumped parameters and practical design parameters for the MR engine mount. The program flowchart for the improved non-dominated sorting genetic algorithm (NSGA-II) is given. The obtained results demonstrate the effectiveness of the proposed optimization approach in minimizing the total of force transmissibility over several frequency ranges addressed.
Alvarado, Maria Gabriela; Schwartz, David A
2017-01-01
-The global epidemic of Zika virus (ZIKV) infection has emerged as an important public health problem affecting pregnant women and their infants. -To review the causal association between ZIKV infection during pregnancy and intrauterine fetal infection, microcephaly, brain damage, congenital malformation syndrome, and experimental laboratory models of fetal infection. Many questions remain regarding the risk factors, pathophysiology, epidemiology, and timing of maternal-fetal transmission and disease. These include mechanisms of fetal brain damage and microcephaly; the role of covariables, such as viral burden, duration of viremia, and host genetics, on vertical transmission; and the clinical and pathologic spectrum of congenital Zika syndrome. Additional questions include defining the potential long-term physical and neurobehavioral outcomes for infected infants, whether maternal or fetal host genetics influence the clinical outcome, and whether ZIKV infection can cause maternal morbidity. Finally, are experimental laboratory and animal models of ZIKV infection helpful in addressing maternal-fetal viral transmission and the development of congenital microcephaly? This communication provides current information and attempts to address some of these important questions. -Comprehensive review of published scientific literature. -Recent advances in epidemiology, clinical medicine, pathology, and experimental studies have provided a great amount of new information regarding vertical ZIKV transmission and the mechanisms of congenital microcephaly, brain damage, and congenital Zika syndrome in a relatively short time. However, much work still needs to be performed to more completely understand the maternal and fetal aspects of this new and emerging viral disease.
Ya-Umphan, Phubeth; Cerqueira, Dominique; Parker, Daniel M; Cottrell, Gilles; Poinsignon, Anne; Remoue, Franck; Brengues, Cecile; Chareonviriyaphap, Theeraphap; Nosten, Francois; Corbel, Vincent
2017-02-01
The modalities of malaria transmission along the Thailand-Myanmar border are poorly understood. Here we address the relevance of using a specific Anopheles salivary biomarker to measure the risk among humans of exposure to Anopheles bites. Serologic surveys were conducted from May 2013 to December 2014 in 4 sentinel villages. More than 9400 blood specimens were collected in filter papers from all inhabitants at baseline and then every 3 months thereafter, for up to 18 months, for analysis by enzyme-linked immunosorbent assay. The relationship between the intensity of the human antibody response and entomological indicators of transmission (human biting rates and entomological inoculation rates [EIRs]) was studied using a multivariate 3-level mixed model analysis. Heat maps for human immunoglobulin G (IgG) responses for each village and survey time point were created using QGIS 2.4. The levels of IgG response among participants varied significantly according to village, season, and age (P<.001) and were positively associated with the abundance of total Anopheles species and primary malaria vectors and the EIR (P<.001). Spatial clusters of high-IgG responders were identified across space and time within study villages. The gSG6-P1 biomarker has great potential to address the risk of transmission along the Thailand-Myanmar border and represents a promising tool to guide malaria interventions. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.
Ultrathin metal-semiconductor-metal resonator for angle invariant visible band transmission filters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Kyu-Tae; Seo, Sungyong; Yong Lee, Jae
We present transmission visible wavelength filters based on strong interference behaviors in an ultrathin semiconductor material between two metal layers. The proposed devices were fabricated on 2 cm × 2 cm glass substrate, and the transmission characteristics show good agreement with the design. Due to a significantly reduced light propagation phase change associated with the ultrathin semiconductor layer and the compensation in phase shift of light reflecting from the metal surface, the filters show an angle insensitive performance up to ±70°, thus, addressing one of the key challenges facing the previously reported photonic and plasmonic color filters. This principle, described in this paper, canmore » have potential for diverse applications ranging from color display devices to the image sensors.« less
Kostal, Lubomir; Kobayashi, Ryota
2015-10-01
Information theory quantifies the ultimate limits on reliable information transfer by means of the channel capacity. However, the channel capacity is known to be an asymptotic quantity, assuming unlimited metabolic cost and computational power. We investigate a single-compartment Hodgkin-Huxley type neuronal model under the spike-rate coding scheme and address how the metabolic cost and the decoding complexity affects the optimal information transmission. We find that the sub-threshold stimulation regime, although attaining the smallest capacity, allows for the most efficient balance between the information transmission and the metabolic cost. Furthermore, we determine post-synaptic firing rate histograms that are optimal from the information-theoretic point of view, which enables the comparison of our results with experimental data. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
The optimization of wireless power transmission: design and realization.
Jia, Zhiwei; Yan, Guozheng; Liu, Hua; Wang, Zhiwu; Jiang, Pingping; Shi, Yu
2012-09-01
A wireless power transmission system is regarded as a practical way of solving power-shortage problems in multifunctional active capsule endoscopes. The uniformity of magnetic flux density, frequency stability and orientation stability are used to evaluate power transmission stability, taking into consideration size and safety constraints. Magnetic field safety and temperature rise are also considered. Test benches are designed to measure the relevent parameters. Finally, a mathematical programming model in which these constraints are considered is proposed to improve transmission efficiency. To verify the feasibility of the proposed method, various systems for a wireless active capsule endoscope are designed and evaluated. The optimal power transmission system has the capability to supply continuously at least 500 mW of power with a transmission efficiency of 4.08%. The example validates the feasibility of the proposed method. Introduction of novel designs enables further improvement of this method. Copyright © 2012 John Wiley & Sons, Ltd.
NASA Astrophysics Data System (ADS)
Marie, Tiphanie; Yesou, Herve; Huber, Claire; De Fraipont, Paul; Uribe, Carlos; Lacaux, Jean-Pierre; Lafaye, Murielle; Lai, Xijun; Desnos, Yves-Louis
2013-01-01
This paper present the method used to determine the areas where schistosomiasis transmission is the higher. A primary work was necessary to this study: identification of potential presence of schistosomiasis japonicum’s vector in Poyang lakeshore area (Jiangxi Province, P.R. China). Results obtained from its first work were crossing with the most risky human activities and with villages to elaborate a level of transmission risk. The first parameter determined concern fishing, which was identified like the most risky activity for schistosomiasis transmission, and fish traps were digitalized using a very high resolution ALOS data. The second parameter is about the risky areas for buffalo grazing, and vector potential presence areas were crossed with village proximity to determine the most risky areas for human transmission. The third parameter built is a level of risk for each village digitalized around Poyang Lake, taking into account the proximity and level of potential presence of vector’s areas.
77 FR 21766 - Midwest Independent Transmission System Operator, Inc.; Notice of Technical Conference
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... Project Fetal-Infant Mortality Review: Human Immunodeficiency Virus Prevention Methodology (FHPM)--New... Mortality Review: Human Immunodeficiency Virus Prevention Methodology (FHPM) is designed to identify and... investigation and improvement strategy. In order to address perinatal HIV transmission at the community level...
Integrated Diseases Surveillance Project (IDSP) through a consultant's lens.
Suresh, K
2008-01-01
India has long experienced one of the highest burdens of infectious diseases in the world, fueled by factors including a large population, high poverty levels, poor sanitation, and problems with access to health care and preventive services. It has traditionally been difficult to monitor disease burden and trends in India, even more difficult to detect, diagnose, and control outbreaks until they had become quite large. In an effort to improve the surveillance and response infrastructure in the country, in November 2004 the Integrated Disease Surveillance Project (IDSP) was initiated with funding from the World Bank. Given the surveillance challenges in India, the project seeks to accomplish its goals through, having a small list of priority conditions, many of which are syndrome-based at community and sub center level and easily recognizable at the out patients and inpatients care of facilities at lowest levels of the health care system, a simplified battery of laboratory tests and rapid test kits, and reporting of largely aggregate data rather than individual case reporting. The project also includes activities that are relatively high technology, such as computerization, electronic data transmission, and video conferencing links for communication and training. The project is planned to be implemented all over the country in a phased manner with a stress on 14 focus states for intensive follow-up to demonstrate successful implementation of IDSP. The National Institute of Communicable Diseases chosen to provide national leadership may have to immediately address five issues. First, promote surveillance through major hospitals (both in public and private sector) and active surveillance through health system staff and community, second, build capacity for data collation, analysis, interpretation to recognize warning signal of outbreak, and institute public health action, third, develop a system which allows availability of quality test kits at district and state laboratories and/or culture facilities at identified laboratories and a national training program to build capacities for performing testing and obtaining high quality results, fourth, there must be a process established by which an appropriate quality assurance program can be implemented and fifth, encourage use of IT infrastructure for data transmission, analysis, routine communication (E-mail etc) and videoconferencing for troubleshooting, consultations and epidemiological investigations. These five activities must be addressed at the national level and cannot be left up to individual states/districts.
Implementation study of wearable sensors for activity recognition systems.
Rezaie, Hamed; Ghassemian, Mona
2015-08-01
This Letter investigates and reports on a number of activity recognition methods for a wearable sensor system. The authors apply three methods for data transmission, namely 'stream-based', 'feature-based' and 'threshold-based' scenarios to study the accuracy against energy efficiency of transmission and processing power that affects the mote's battery lifetime. They also report on the impact of variation of sampling frequency and data transmission rate on energy consumption of motes for each method. This study leads us to propose a cross-layer optimisation of an activity recognition system for provisioning acceptable levels of accuracy and energy efficiency.
Astroglial Metabolic Networks Sustain Hippocampal Synaptic Transmission
NASA Astrophysics Data System (ADS)
Rouach, Nathalie; Koulakoff, Annette; Abudara, Veronica; Willecke, Klaus; Giaume, Christian
2008-12-01
Astrocytes provide metabolic substrates to neurons in an activity-dependent manner. However, the molecular mechanisms involved in this function, as well as its role in synaptic transmission, remain unclear. Here, we show that the gap-junction subunit proteins connexin 43 and 30 allow intercellular trafficking of glucose and its metabolites through astroglial networks. This trafficking is regulated by glutamatergic synaptic activity mediated by AMPA receptors. In the absence of extracellular glucose, the delivery of glucose or lactate to astrocytes sustains glutamatergic synaptic transmission and epileptiform activity only when they are connected by gap junctions. These results indicate that astroglial gap junctions provide an activity-dependent intercellular pathway for the delivery of energetic metabolites from blood vessels to distal neurons.
Astroglial metabolic networks sustain hippocampal synaptic transmission.
Rouach, Nathalie; Koulakoff, Annette; Abudara, Veronica; Willecke, Klaus; Giaume, Christian
2008-12-05
Astrocytes provide metabolic substrates to neurons in an activity-dependent manner. However, the molecular mechanisms involved in this function, as well as its role in synaptic transmission, remain unclear. Here, we show that the gap-junction subunit proteins connexin 43 and 30 allow intercellular trafficking of glucose and its metabolites through astroglial networks. This trafficking is regulated by glutamatergic synaptic activity mediated by AMPA receptors. In the absence of extracellular glucose, the delivery of glucose or lactate to astrocytes sustains glutamatergic synaptic transmission and epileptiform activity only when they are connected by gap junctions. These results indicate that astroglial gap junctions provide an activity-dependent intercellular pathway for the delivery of energetic metabolites from blood vessels to distal neurons.
Kondo, Yohei; Yada, Yuichiro; Haga, Tatsuya; Takayama, Yuzo; Isomura, Takuya; Jimbo, Yasuhiko; Fukayama, Osamu; Hoshino, Takayuki; Mabuchi, Kunihiko
2017-04-29
Synapse elimination and neurite pruning are essential processes for the formation of neuronal circuits. These regressive events depend on neural activity and occur in the early postnatal days known as the critical period, but what makes this temporal specificity is not well understood. One possibility is that the neural activities during the developmentally regulated shift of action of GABA inhibitory transmission lead to the critical period. Moreover, it has been reported that the shifting action of the inhibitory transmission on immature neurons overlaps with synapse elimination and neurite pruning and that increased inhibitory transmission by drug treatment could induce temporal shift of the critical period. However, the relationship among these phenomena remains unclear because it is difficult to experimentally show how the developmental shift of inhibitory transmission influences neural activities and whether the activities promote synapse elimination and neurite pruning. In this study, we modeled synapse elimination in neuronal circuits using the modified Izhikevich's model with functional shifting of GABAergic transmission. The simulation results show that synaptic pruning within a specified period like the critical period is spontaneously generated as a function of the developmentally shifting inhibitory transmission and that the specific firing rate and increasing synchronization of neural circuits are seen at the initial stage of the critical period. This temporal relationship was experimentally supported by an in vitro primary culture of rat cortical neurons in a microchannel on a multi-electrode array (MEA). The firing rate decreased remarkably between the 18-25 days in vitro (DIV), and following these changes in the firing rate, the neurite density was slightly reduced. Our simulation and experimental results suggest that decreasing neural activity due to developing inhibitory synaptic transmission could induce synapse elimination and neurite pruning at particular time such as the critical period. Additionally, these findings indicate that we can estimate the maturity level of inhibitory transmission and the critical period by measuring the firing rate and the degree of synchronization in engineered neural networks. Copyright © 2017 Elsevier Inc. All rights reserved.
Expert review on poliovirus immunity and transmission.
Duintjer Tebbens, Radboud J; Pallansch, Mark A; Chumakov, Konstantin M; Halsey, Neal A; Hovi, Tapani; Minor, Philip D; Modlin, John F; Patriarca, Peter A; Sutter, Roland W; Wright, Peter F; Wassilak, Steven G F; Cochi, Stephen L; Kim, Jong-Hoon; Thompson, Kimberly M
2013-04-01
Successfully managing risks to achieve wild polioviruses (WPVs) eradication and address the complexities of oral poliovirus vaccine (OPV) cessation to stop all cases of paralytic poliomyelitis depends strongly on our collective understanding of poliovirus immunity and transmission. With increased shifting from OPV to inactivated poliovirus vaccine (IPV), numerous risk management choices motivate the need to understand the tradeoffs and uncertainties and to develop models to help inform decisions. The U.S. Centers for Disease Control and Prevention hosted a meeting of international experts in April 2010 to review the available literature relevant to poliovirus immunity and transmission. This expert review evaluates 66 OPV challenge studies and other evidence to support the development of quantitative models of poliovirus transmission and potential outbreaks. This review focuses on characterization of immunity as a function of exposure history in terms of susceptibility to excretion, duration of excretion, and concentration of excreted virus. We also discuss the evidence of waning of host immunity to poliovirus transmission, the relationship between the concentration of poliovirus excreted and infectiousness, the importance of different transmission routes, and the differences in transmissibility between OPV and WPV. We discuss the limitations of the available evidence for use in polio risk models, and conclude that despite the relatively large number of studies on immunity, very limited data exist to directly support quantification of model inputs related to transmission. Given the limitations in the evidence, we identify the need for expert input to derive quantitative model inputs from the existing data. © 2012 Society for Risk Analysis.
Satellite Power Systems /SPS/ - Overview of system studies and critical technology
NASA Technical Reports Server (NTRS)
Manson, S. V.
1980-01-01
Systems studies and critical technology issues for the development and evaluation of Satellite Power Systems (SPS) for the photovoltaic generation of electrical energy and its transmission to earth are reviewed. Initial concept studies completed in 1976 and system definition studies initiated in the same year have indicated the technical feasibility of SPS and identified challenging issues to be addressed as part of the SPS Concept Development and Evaluation Program. Systems considered in the study include photovoltaic and solar thermal power conversion configurations employing klystron or solid state microwave generators or lasers for power transmission, and power transmission options, system constructability and in-orbit and ground operations. Technology investigations are being performed in the areas of microwave power transmission, structure/controls interactions and the behavior of key materials in the space/SPS environment. Favorable results have been obtained in the areas of microwave phase distribution and phase control, dc-RF conversion, antenna radiating element, and no insurmountable problems have been discovered in any of the investigations to date.
The efficacy of serostatus disclosure for HIV Transmission risk reduction.
O'Connell, Ann A; Reed, Sandra J; Serovich, Julianne A
2015-02-01
Interventions to assist HIV+ persons in disclosing their serostatus to sexual partners can play an important role in curbing rates of HIV transmission among men who have sex with men (MSM). Based on the methods of Pinkerton and Galletly (AIDS Behav 11:698-705, 2007), we develop a mathematical probability model for evaluating effectiveness of serostatus disclosure in reducing the risk of HIV transmission and extend the model to examine the impact of serosorting. In baseline data from 164 HIV+ MSM participating in a randomized controlled trial of a disclosure intervention, disclosure is associated with a 45.0 % reduction in the risk of HIV transmission. Accounting for serosorting, a 61.2 % reduction in risk due to disclosure was observed in serodisconcordant couples. The reduction in risk for seroconcordant couples was 38.4 %. Evidence provided supports the value of serostatus disclosure as a risk reduction strategy in HIV+ MSM. Interventions to increase serostatus disclosure and that address serosorting behaviors are needed.
The Efficacy of Serostatus Disclosure for HIV Transmission Risk Reduction
O’Connell, Ann A.; Serovich, Julianne A.
2015-01-01
Interventions to assist HIV+ persons in disclosing their serostatus to sexual partners can play an important role in curbing rates of HIV transmission among men who have sex with men (MSM). Based on the methods of Pinkerton and Galletly (AIDS Behav 11:698–705, 2007), we develop a mathematical probability model for evaluating effectiveness of serostatus disclosure in reducing the risk of HIV transmission and extend the model to examine the impact of serosorting. In baseline data from 164 HIV+ MSM participating in a randomized controlled trial of a disclosure intervention, disclosure is associated with a 45.0 % reduction in the risk of HIV transmission. Accounting for serosorting, a 61.2 % reduction in risk due to disclosure was observed in serodisconcordant couples. The reduction in risk for seroconcordant couples was 38.4 %. Evidence provided supports the value of serostatus disclosure as a risk reduction strategy in HIV+ MSM. Interventions to increase serostatus disclosure and that address serosorting behaviors are needed. PMID:25164375
Ben-Shachar, Rotem; Koelle, Katia
2018-06-15
An extensive body of theory addresses the topic of pathogen virulence evolution, yet few studies have empirically demonstrated the presence of fitness trade-offs that would select for intermediate virulence. Here we show the presence of transmission-clearance trade-offs in dengue virus using viremia measurements. By fitting a within-host model to these data, we further find that the interaction between dengue and the host immune response can account for the observed trade-offs. Finally, we consider dengue virulence evolution when selection acts on the virus's production rate. By combining within-host model simulations with empirical findings on how host viral load affects human-to-mosquito transmission success, we show that the virus's transmission potential is maximized at production rates associated with intermediate virulence and that the optimal production rate critically depends on dengue's epidemiological context. These results indicate that long-term changes in dengue's global distribution impact the invasion and spread of virulent dengue virus genotypes.
Effect of presynaptic membrane potential on electrical vs. chemical synaptic transmission
Evans, Colin G.; Ludwar, Bjoern Ch.; Kang, Timothy
2011-01-01
The growing realization that electrical coupling is present in the mammalian brain has sparked renewed interest in determining its functional significance and contrasting it with chemical transmission. One question of interest is whether the two types of transmission can be selectively regulated, e.g., if a cell makes both types of connections can electrical transmission occur in the absence of chemical transmission? We explore this issue in an experimentally advantageous preparation. B21, the neuron we study, is an Aplysia sensory neuron involved in feeding that makes electrical and chemical connections with other identified cells. Previously we demonstrated that chemical synaptic transmission is membrane potential dependent. It occurs when B21 is centrally depolarized prior to and during peripheral activation, but does not occur if B21 is peripherally activated at its resting membrane potential. In this article we study effects of membrane potential on electrical transmission. We demonstrate that maximal potentiation occurs in different voltage ranges for the two types of transmission, with potentiation of electrical transmission occurring at more hyperpolarized potentials (i.e., requiring less central depolarization). Furthermore, we describe a physiologically relevant type of stimulus that induces both spiking and an envelope of depolarization in the somatic region of B21. This depolarization does not induce functional chemical synaptic transmission but is comparable to the depolarization needed to maximally potentiate electrical transmission. In this study we therefore characterize a situation in which electrical and chemical transmission can be selectively controlled by membrane potential. PMID:21593394
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Phillips, J Craig; Webel, Allison; Rose, Carol Dawson; Corless, Inge B; Sullivan, Kathleen M; Voss, Joachim; Wantland, Dean; Nokes, Kathleen; Brion, John; Chen, Wei-Ti; Iipinge, Scholastika; Eller, Lucille Sanzero; Tyer-Viola, Lynda; Rivero-Méndez, Marta; Nicholas, Patrice K; Johnson, Mallory O; Maryland, Mary; Kemppainen, Jeanne; Portillo, Carmen J; Chaiphibalsarisdi, Puangtip; Kirksey, Kenn M; Sefcik, Elizabeth; Reid, Paula; Cuca, Yvette; Huang, Emily; Holzemer, William L
2013-08-08
Human rights approaches to manage HIV and efforts to decriminalize HIV exposure/transmission globally offer hope to persons living with HIV (PLWH). However, among vulnerable populations of PLWH, substantial human rights and structural challenges (disadvantage and injustice that results from everyday practices of a well-intentioned liberal society) must be addressed. These challenges span all ecosocial context levels and in North America (Canada and the United States) can include prosecution for HIV nondisclosure and HIV exposure/transmission. Our aims were to: 1) Determine if there were associations between the social structural factor of criminalization of HIV exposure/transmission, the individual factor of perceived social capital (resources to support one's life chances and overcome life's challenges), and HIV antiretroviral therapy (ART) adherence among PLWH and 2) describe the nature of associations between the social structural factor of criminalization of HIV exposure/transmission, the individual factor of perceived social capital, and HIV ART adherence among PLWH. We used ecosocial theory and social epidemiology to guide our study. HIV related criminal law data were obtained from published literature. Perceived social capital and HIV ART adherence data were collected from adult PLWH. Correlation and logistic regression were used to identify and characterize observed associations. Among a sample of adult PLWH (n = 1873), significant positive associations were observed between perceived social capital, HIV disclosure required by law, and self-reported HIV ART adherence. We observed that PLWH who have higher levels of perceived social capital and who live in areas where HIV disclosure is required by law reported better average adherence. In contrast, PLWH who live in areas where HIV transmission/exposure is a crime reported lower 30-day medication adherence. Among our North American participants, being of older age, of White or Hispanic ancestry, and having higher perceived social capital, were significant predictors of better HIV ART adherence. Treatment approaches offer clear advantages in controlling HIV and reducing HIV transmission at the population level. These advantages, however, will have limited benefit for adherence to treatments without also addressing the social and structural challenges that allow HIV to continue to spread among society's most vulnerable populations.
Schistosomiasis in Malawi: a systematic review.
Makaula, Peter; Sadalaki, John R; Muula, Adamson S; Kayuni, Sekeleghe; Jemu, Samuel; Bloch, Paul
2014-12-10
Schistosomiasis remains an important public health problem that undermines social and economic development in tropical regions of the world, mainly Sub-Saharan Africa. We are not aware of any systematic review of the literature of the epidemiology and transmission of schistosomiasis in Malawi since 1985. Therefore, we reviewed the current state of knowledge of schistosomiasis epidemiology and transmission in this country and identified knowledge gaps and relevant areas for future research and research governance. We conducted computer-aided literature searches of Medline, SCOPUS and Google Scholar using the keywords: "schistosomiasis", "Bilharzia", "Bulinus" and "Biomphalaria" in combination with "Malawi". These searches were supplemented by iterative reviews of reference lists for relevant publications in peer reviewed international scientific journals or other media. The recovered documents were reviewed for their year of publication, location of field or laboratory work, authorship characteristics, ethics review, funding sources as well as their findings regarding parasite and intermediate host species, environmental aspects, geographical distribution, seasonality of transmission, and infection prevalence and intensities. A total of 89 documents satisfied the inclusion criteria and were reviewed. Of these, 76 were published in international scientific journals, 68 were peer reviewed and 54 were original research studies. Most of the documents addressed urinary schistosomiasis and about two thirds of them dealt with the definitive host. Few documents addressed the parasites and the intermediate hosts. While urinary schistosomiasis occurs in most parts of Malawi, intestinal schistosomiasis mainly occurs in the central and southern highlands, Likoma Island and Lower Shire. Studies in selected communities estimated prevalence rates of up to 94.9% for Schistosoma haematobium and up to 67.0% for Schistosoma mansoni with considerable geographical variation. The main intermediate host species are Bulinus globosus and Bulinus nyassanus for urinary schistosomiasis and Biomphalaria pfeifferi for intestinal schistosomiasis. Seasonality of transmission tends to vary according to geographical, environmental, biological and behavioural factors. Transmission of schistosomiasis in Malawi appears to be highly focal, with considerable variation in space and time. Many locations have not been covered by epidemiological investigations and, thus, information on the transmission of schistosomiasis in Malawi remains fragmented. Functional infection risk assessment systems based on systematic investigations and surveillance are required for developing informed prevention and control strategies.
Cannabinoid–dopamine interactions in the physiology and physiopathology of the basal ganglia
García, Concepción; Palomo‐Garo, Cristina; Gómez‐Gálvez, Yolanda
2015-01-01
Endocannabinoids and their receptors play a modulatory role in the control of dopamine transmission in the basal ganglia. However, this influence is generally indirect and exerted through the modulation of GABA and glutamate inputs received by nigrostriatal dopaminergic neurons, which lack cannabinoid CB1 receptors although they may produce endocannabinoids. Additional evidence suggests that CB2 receptors may be located in nigrostriatal dopaminergic neurons, and that certain eicosanoid‐related cannabinoids may directly activate TRPV1 receptors, which have been found in nigrostriatal dopaminergic neurons, thus allowing in both cases a direct regulation of dopamine transmission by specific cannabinoids. In addition, CB1 receptors form heteromers with dopaminergic receptors which provide another pathway to direct interactions between both systems, in this case at the postsynaptic level. Through these direct mechanisms or through indirect mechanisms involving GABA or glutamate neurons, cannabinoids may interact with dopaminergic transmission in the basal ganglia and this is likely to have important effects on dopamine‐related functions in these structures (i.e. control of movement) and, particularly, on different pathologies affecting these processes, in particular, Parkinson's disease, but also dyskinesia, dystonia and other pathological conditions. The present review will address the current literature supporting these cannabinoid–dopamine interactions at the basal ganglia, with emphasis on aspects dealing with the physiopathological consequences of these interactions. Linked Articles This article is part of a themed section on Updating Neuropathology and Neuropharmacology of Monoaminergic Systems. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v173.13/issuetoc PMID:26059564
Evans, Geoffrey J.; Kirkby, Paul A.; Nadella, K. M. Naga Srinivas; Marin, Bóris; Silver, R. Angus
2016-01-01
A spherical acousto-optic lens (AOL) consists of four acousto-optic deflectors (AODs) that can rapidly and precisely control the focal position of an optical beam in 3D space. Development and application of AOLs has increased the speed at which 3D random access point measurements can be performed with a two-photon microscope. This has been particularly useful for measuring brain activity with fluorescent reporter dyes because neuronal signalling is rapid and sparsely distributed in 3D space. However, a theoretical description of light propagation through AOLs has lagged behind their development, resulting in only a handful of simplified principles to guide AOL design and optimization. To address this we have developed a ray-based computer model of an AOL incorporating acousto-optic diffraction and refraction by anisotropic media. We extended an existing model of a single AOD with constant drive frequency to model a spherical AOL: four AODs in series driven with linear chirps. AOL model predictions of the relationship between optical transmission efficiency and acoustic drive frequency including second order diffraction effects closely matched experimental measurements from a 3D two-photon AOL microscope. Moreover, exploration of different AOL drive configurations identified a new simple rule for maximizing the field of view of our compact AOL design. By providing a theoretical basis for understanding optical transmission through spherical AOLs, our open source model is likely to be useful for comparing and improving different AOL designs, as well as identifying the acoustic drive configurations that provide the best transmission performance over the 3D focal region. PMID:26368449
Recent Insights into the HIV/AIDS Pandemic
Becerra, Juan C.; Bildstein, Lukas S.; Gach, Johannes S.
2016-01-01
Etiology, transmission and protection: Transmission of HIV, the causative agent of AIDS, occurs predominantly through bodily fluids. Factors that significantly alter the risk of HIV transmission include male circumcision, condom use, high viral load, and the presence of other sexually transmitted diseases. Pathology/Symptomatology: HIV infects preferentially CD4+ T lymphocytes, and Monocytes. Because of their central role in regulating the immune response, depletion of CD4+ T cells renders the infected individual incapable of adequately responding to microorganisms otherwise inconsequential. Epidemiology, incidence and prevalence: New HIV infections affect predominantly young heterosexual women and homosexual men. While the mortality rates of AIDS related causes have decreased globally in recent years due to the use of highly active antiretroviral therapy (HAART) treatment, a vaccine remains an elusive goal. Treatment and curability: For those afflicted HIV infection remains a serious illness. Nonetheless, the use of advanced therapeutics have transformed a dire scenario into a chronic condition with near average life spans. When to apply those remedies appears to be as important as the remedies themselves. The high rate of HIV replication and the ability to generate variants are central to the viral survival strategy and major barriers to be overcome. Molecular mechanisms of infection: In this review, we assemble new details on the molecular events from the attachment of the virus, to the assembly and release of the viral progeny. Yet, much remains to be learned as understanding of the molecular mechanisms used in viral replication and the measures engaged in the evasion of immune surveillance will be important to develop effective interventions to address the global HIV pandemic. PMID:28357381
Evans, Geoffrey J; Kirkby, Paul A; Naga Srinivas Nadella, K M; Marin, Bóris; Angus Silver, R
2015-09-07
A spherical acousto-optic lens (AOL) consists of four acousto-optic deflectors (AODs) that can rapidly and precisely control the focal position of an optical beam in 3D space. Development and application of AOLs has increased the speed at which 3D random access point measurements can be performed with a two-photon microscope. This has been particularly useful for measuring brain activity with fluorescent reporter dyes because neuronal signalling is rapid and sparsely distributed in 3D space. However, a theoretical description of light propagation through AOLs has lagged behind their development, resulting in only a handful of simplified principles to guide AOL design and optimization. To address this we have developed a ray-based computer model of an AOL incorporating acousto-optic diffraction and refraction by anisotropic media. We extended an existing model of a single AOD with constant drive frequency to model a spherical AOL: four AODs in series driven with linear chirps. AOL model predictions of the relationship between optical transmission efficiency and acoustic drive frequency including second order diffraction effects closely matched experimental measurements from a 3D two-photon AOL microscope. Moreover, exploration of different AOL drive configurations identified a new simple rule for maximizing the field of view of our compact AOL design. By providing a theoretical basis for understanding optical transmission through spherical AOLs, our open source model is likely to be useful for comparing and improving different AOL designs, as well as identifying the acoustic drive configurations that provide the best transmission performance over the 3D focal region.
Cole, E C; Cook, C E
1998-08-01
Assessment of strategies for engineering controls for the prevention of airborne infectious disease transmission to patients and to health care and related workers requires consideration of the factors relevant to aerosol characterization. These factors include aerosol generation, particle size and concentrations, organism viability, infectivity and virulence, airflow and climate, and environmental sampling and analysis. The major focus on attention to engineering controls comes from recent increases in tuberculosis, particularly the multidrug-resistant varieties in the general hospital population, the severely immunocompromised, and those in at-risk and confined environments such as prisons, long-term care facilities, and shelters for the homeless. Many workers are in close contact with persons who have active, undiagnosed, or insufficiently treated tuberculosis. Additionally, patients and health care workers may be exposed to a variety of pathogenic human viruses, opportunistic fungi, and bacteria. This report therefore focuses on the nature of infectious aerosol transmission in an attempt to determine which factors can be systematically addressed to result in proven, applied engineering approaches to the control of infectious aerosols in hospital and health care facility environments. The infectious aerosols of consideration are those that are generated as particles of respirable size by both human and environmental sources and that have the capability of remaining viable and airborne for extended periods in the indoor environment. This definition precludes skin and mucous membrane exposures occurring from splashes (rather than true aerosols) of blood or body fluids containing infectious disease agents. There are no epidemiologic or laboratory studies documenting the transmission of bloodborne virus by way of aerosols.
Water deficit enhances the transmission of plant viruses by insect vectors
Yvon, Michel; Vile, Denis; Dader, Beatriz; Fereres, Alberto
2017-01-01
Drought is a major threat to crop production worldwide and is accentuated by global warming. Plant responses to this abiotic stress involve physiological changes overlapping, at least partially, the defense pathways elicited both by viruses and their herbivore vectors. Recently, a number of theoretical and empirical studies anticipated the influence of climate changes on vector-borne viruses of plants and animals, mainly addressing the effects on the virus itself or on the vector population dynamics, and inferring possible consequences on virus transmission. Here, we directly assess the effect of a severe water deficit on the efficiency of aphid-transmission of the Cauliflower mosaic virus (CaMV) or the Turnip mosaic virus (TuMV). For both viruses, our results demonstrate that the rate of vector-transmission is significantly increased from water-deprived source plants: CaMV transmission reproducibly increased by 34% and that of TuMV by 100%. In both cases, the enhanced transmission rate could not be explained by a higher virus accumulation, suggesting a more complex drought-induced process that remains to be elucidated. The evidence that infected plants subjected to drought are much better virus sources for insect vectors may have extensive consequences for viral epidemiology, and should be investigated in a wide range of plant-virus-vector systems. PMID:28467423
Water deficit enhances the transmission of plant viruses by insect vectors.
van Munster, Manuella; Yvon, Michel; Vile, Denis; Dader, Beatriz; Fereres, Alberto; Blanc, Stéphane
2017-01-01
Drought is a major threat to crop production worldwide and is accentuated by global warming. Plant responses to this abiotic stress involve physiological changes overlapping, at least partially, the defense pathways elicited both by viruses and their herbivore vectors. Recently, a number of theoretical and empirical studies anticipated the influence of climate changes on vector-borne viruses of plants and animals, mainly addressing the effects on the virus itself or on the vector population dynamics, and inferring possible consequences on virus transmission. Here, we directly assess the effect of a severe water deficit on the efficiency of aphid-transmission of the Cauliflower mosaic virus (CaMV) or the Turnip mosaic virus (TuMV). For both viruses, our results demonstrate that the rate of vector-transmission is significantly increased from water-deprived source plants: CaMV transmission reproducibly increased by 34% and that of TuMV by 100%. In both cases, the enhanced transmission rate could not be explained by a higher virus accumulation, suggesting a more complex drought-induced process that remains to be elucidated. The evidence that infected plants subjected to drought are much better virus sources for insect vectors may have extensive consequences for viral epidemiology, and should be investigated in a wide range of plant-virus-vector systems.
Prions and prion diseases: fundamentals and mechanistic details.
Ryou, Chongsuk
2007-07-01
Prion diseases, often called transmissible spongiform encephalopathies (TSEs), are infectious diseases that accompany neurological dysfunctions in many mammalian hosts. Prion diseases include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE, "mad cow disease") in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elks. The cause of these fatal diseases is a proteinaceous pathogen termed prion that lacks functional nucleic acids. As demonstrated in the BSE outbreak and its transmission to humans, the onset of disease is not limited to a certain species but can be transmissible from one host species to another. Such a striking nature ofprions has generated huge concerns in public health and attracted serious attention in the scientific communities. To date, the potential transmission ofprions to humans via foodbome infectiorn and iatrogenic routes has not been alleviated. Rather, the possible transmission of human to human or cervids to human aggravates the terrifying situation across the globe. In this review, basic features about prion diseases including clinical and pathological characteristics, etiology, and transmission of diseases are described. Based on recently accumulated evidences, the molecular and biochemical aspects of prions, with an emphasis on the molecular interactions involved in prion conversion that is critical during prion replication and pathogenesis, are also addressed.
Molecular epidemiology of bovine anaplasmosis with a particular focus in Mexico.
Rodríguez, Sergio D; García Ortiz, Miguel Angel; Jiménez Ocampo, Rafael; Vega y Murguía, Carlos A
2009-12-01
Bovine anaplasmosis, caused by the rickettsia Anaplasma marginale, has a worldwide distribution and is the cause of great economic losses in developing countries where it is highly endemic. Transmission is carried mainly by ixodid ticks: Dermacentor spp. and Rhipicephalus (Boophilus) spp. Mechanical transmission is important in disseminating the disease within and across herds. The relationship between the rickettsia, the host and the vector is complex. Several surface proteins (Msps) have been described with functions that span from adhesins towards the erythrocyte and tick cells to evasion of the immune system of the host through the generation of antigenic variants. Biologic transmission of A. marginale through Dermacentor ticks has been well studied but many questions are unresolved as to how this organism spreads within and across herds and little is known about the role Rhipicephalus (Boophilus) ticks play in transmission in the Americas. Mechanical transmission in the absence of ticks and lack of transmission through ticks are questions that need to be addressed. Phylogenetic studies of the rickettsia show wide antigenic and genetic mosaics which affects the design of new vaccines. In the present work we will discuss the molecular elements in the relationship between the rickettsia, the tick and the mammalian host associated to the distribution and persistence of the pathogen in nature.
NASA Astrophysics Data System (ADS)
Liang, C.; Rogers, C. A.; Fuller, C. R.
1991-02-01
A theoretical analysis of sound transmission/radiation of shape-memory alloy (SMA) hybrid composite panels is presented. Unlike other composite materials, SMA hybrid composite is dynamically tunable by electrical activation of the SMA fibers and has numerous active control capabilities. Two of the concepts that will be briefly described and utilized in this paper are referred to as active property tuning (APT) and active strain energy tuning (ASET). Tuning or activating the embedded shape-memory alloy fibers in conventional composite materials changes the overall stiffness of the SMA hybrid composite structure and consequently changes natural frequency and mode shapes. The sound transmission and radiation from a composite panel is related to its frequency and mode shapes. Because of the capability to change both the natural frequency and mode shapes, the acoustic characteristics of SMA hybrid composite plates can be changed as well. The directivity pattern, radiation efficiency, and transmission loss of laminated composite materials are investigated based on 'composite' mode shapes in order to derive a basic understanding of the nature and authority of acoustic control by use of SMA hybrid composites.
NASA Technical Reports Server (NTRS)
Lizcano, Maricela
2017-01-01
High voltage hybrid electric propulsion systems are now pushing new technology development efforts for air transportation. A key challenge in hybrid electric aircraft is safe high voltage distribution and transmission of megawatts of power (>20 MW). For the past two years, a multidisciplinary materials research team at NASA Glenn Research Center has investigated the feasibility of distributing high voltage power on future hybrid electric aircraft. This presentation describes the team's approach to addressing this challenge, significant technical findings, and next steps in GRC's materials research effort for MW power distribution on aircraft.
Infectious Prions in the Saliva and Blood of Deer with Chronic Wasting Disease
NASA Astrophysics Data System (ADS)
Mathiason, Candace K.; Powers, Jenny G.; Dahmes, Sallie J.; Osborn, David A.; Miller, Karl V.; Warren, Robert J.; Mason, Gary L.; Hays, Sheila A.; Hayes-Klug, Jeanette; Seelig, Davis M.; Wild, Margaret A.; Wolfe, Lisa L.; Spraker, Terry R.; Miller, Michael W.; Sigurdson, Christina J.; Telling, Glenn C.; Hoover, Edward A.
2006-10-01
A critical concern in the transmission of prion diseases, including chronic wasting disease (CWD) of cervids, is the potential presence of prions in body fluids. To address this issue directly, we exposed cohorts of CWD-naïve deer to saliva, blood, or urine and feces from CWD-positive deer. We found infectious prions capable of transmitting CWD in saliva (by the oral route) and in blood (by transfusion). The results help to explain the facile transmission of CWD among cervids and prompt caution concerning contact with body fluids in prion infections.
[Water contacts in dracunculiasis-infected patients in Mali: transmission risk activities].
Etard, J F; Kodio, B; Traoré, S; Audibert, M
2002-11-01
The aim of this study lies in the identification of human activities responsible for the transmission of the Guinea worm in an endemic village in Diema Region in Mali. Human water contacts observations started after a census followed by the implementation of a bi-monthly notification system, carried out from May to November 1993. Water contacts were noticed and observed from the mid-July to the end of November of the same year. The first case of dracunculiasis observed was randomly drawn out of a list of the families with obvious cases. The patent case activities involving either surface water, traditional wells or bore-hole water were recorded for 10 consecutive days. During this observation period, contacts made by other patients with the same water sources were also recorded. After 14 days, the case list was updated and a new case selected out of families previously selected. This cycle was repeated until the end of the study period. A "contact at risk for transmission" was defined by a close correspondence between the location of the worm's emergence and the surface of the skin exposed to water, within two weeks following emergence. Contacts were described according to water sources, activities in relation to water, date, gender and age. Observations were made on 103 patients who had 2506 activities in relation with a water body: 1132 of these activities implied a skin contact with the water. Only 133 (9%) of these water contacts were at risk for transmission, 75% took place during the months of August and September, 80% were related to surface waters and 20% to traditional wells. Woman household activities and boys games were the major activities at risk, in contrast to economic activities (watering cattle). The low proportion of "at risk activities" evaluated in this study suggests that a small number of water contacts is sufficient to maintain the transmission. The case implications of the current eradication strategy might not be sufficient alone to break the transmission and should therefore be associated with a reinforcement of the use of filters for drinking water together with an health education.
Wasserberg, Gideon; Osnas, Erik E; Rolley, Robert E; Samuel, Michael D
2009-04-01
Emerging wildlife diseases pose a significant threat to natural and human systems. Because of real or perceived risks of delayed actions, disease management strategies such as culling are often implemented before thorough scientific knowledge of disease dynamics is available. Adaptive management is a valuable approach in addressing the uncertainty and complexity associated with wildlife disease problems and can be facilitated by using a formal model.We developed a multi-state computer simulation model using age, sex, infection-stage, and seasonality as a tool for scientific learning and managing chronic wasting disease (CWD) in white-tailed deer Odocoileus virginianus. Our matrix model used disease transmission parameters based on data collected through disease management activities. We used this model to evaluate management issues on density- (DD) and frequency-dependent (FD) transmission, time since disease introduction, and deer culling on the demographics, epizootiology, and management of CWD.Both DD and FD models fit the Wisconsin data for a harvested white-tailed deer population, but FD was slightly better. Time since disease introduction was estimated as 36 (95% CI, 24-50) and 188 (41->200) years for DD and FD transmission, respectively. Deer harvest using intermediate to high non-selective rates can be used to reduce uncertainty between DD and FD transmission and improve our prediction of long-term epidemic patterns and host population impacts. A higher harvest rate allows earlier detection of these differences, but substantially reduces deer abundance.Results showed that CWD has spread slowly within Wisconsin deer populations, and therefore, epidemics and disease management are expected to last for decades. Non-hunted deer populations can develop and sustain a high level of infection, generating a substantial risk of disease spread. In contrast, CWD prevalence remains lower in hunted deer populations, but at a higher prevalence the disease competes with recreational hunting to reduce deer abundance.Synthesis and applications. Uncertainty about density- or frequency-dependent transmission hinders predictions about the long-term impacts of chronic wasting disease on cervid populations and the development of appropriate management strategies. An adaptive management strategy using computer modelling coupled with experimental management and monitoring can be used to test model predictions, identify the likely mode of disease transmission, and evaluate the risks of alternative management responses.
47 CFR 90.20 - Public Safety Pool.
Code of Federal Regulations, 2010 CFR
2010-10-01
... Safety Pool to operate radio stations for transmission of communications essential to official activities... operate stations for transmission of communications essential for the delivery or rendition of emergency... Public Safety Pool to operate radio stations for transmission of communications, as listed below. When...
Implementation study of wearable sensors for activity recognition systems
Ghassemian, Mona
2015-01-01
This Letter investigates and reports on a number of activity recognition methods for a wearable sensor system. The authors apply three methods for data transmission, namely ‘stream-based’, ‘feature-based’ and ‘threshold-based’ scenarios to study the accuracy against energy efficiency of transmission and processing power that affects the mote's battery lifetime. They also report on the impact of variation of sampling frequency and data transmission rate on energy consumption of motes for each method. This study leads us to propose a cross-layer optimisation of an activity recognition system for provisioning acceptable levels of accuracy and energy efficiency. PMID:26609413
Ruger, Jennifer Prah; Lazar, Christina M
2012-01-01
Drug abuse and transmission of HIV during pregnancy are public health problems that adversely affect pregnant women, their children and surrounding communities. Programs that address this vulnerable population have the ability to be cost-effective due to resulting cost savings for mother, child and society. Economic evaluations of programs that address these issues are an important tool to better understand the costs of services and create sustainable healthcare systems. This study critically examined economic evaluations of drug abuse treatment and HIV prevention programs in pregnant women. A systematic review was conducted using the criteria recommended by the Panel on Cost-Effectiveness in Health and Medicine and the British Medical Journal (BMJ) checklist for economic evaluations. The search identified 6 economic studies assessing drug abuse treatment for pregnant women, and 12 economic studies assessing programs that focus on prevention of mother-to-child transmission (PMTCT) of HIV. Results show that many programs for drug abuse treatment and PMTCT among pregnant women are cost-effective or even cost-saving. This study identified several shortcomings in methodology and lack of standardization of current economic evaluations. Efforts to address methodological challenges will help make future studies more comparable and have more influence on policy makers, clinicians and the public. Copyright © 2011 Elsevier Ltd. All rights reserved.
FCA Group LLC request to the EPA regarding greenhouse gas, off-cycle CO2 credits for Active Engine Warm Up used in 2011-2013 model year vehicles and Active Transmission Warm Up Technologies used in 2013 model year vehicles.
NASA Astrophysics Data System (ADS)
Marie, Tiphanie; Lai, Xijun; Huber, Claire; Chen, Xiaoling; Uribe, Carlos; Huang, Shifeng; LaCaux, Jean-Pierre; LaFaye, Murielle; Yesou, Herve
2010-12-01
Earth Observation data were used for mapping potential Schistosomiasis japonica distribution, within Poyang Lake (Jiangxi Province, PR China), as well as transmission risk associated with fishing activities. Areas suitable for the development of Oncomelania hupensis, the intermediate host snail of Schistosoma japonicum, were derived from submersion time parameters and vegetation community indicators. Monthly maps showing the annual dynamic of potential O. hupensis presence areas were obtained from December 2005 to December 2008. Human potential transmission risk was handled through the mapping of settlements and the identification of the principal human activity sensitive to transmission: fishing in the central part of Poyang Lake. Finally, data crossing of the different parameters highlight the potential risk of transmission in most of the fishing nets areas.
NASA Astrophysics Data System (ADS)
Marie, T.; Huber, C.; Yesou, H.
2013-01-01
Schistosomiasis (Bilharzias) is the most frequent disease after malaria in the world. This disease hit 200 million people, and threats 600 million people. In China, Schistosomiasis japonicum, a serious communicable parasitic disease, is endemic along the Yangtze River basin, including monsoon lakes. Risky transmission areas are conditioned by the S. japonicum vector’s presence and human activities and presence. On Poyang Lake, marshlands are the principal area of its development. The aim of this work is to answer : Where are areas suitable for vector’s disease development ? Where and what are the human activities the most exposed to disease transmission ? Where are urban areas with the higher level of disease transmission risk ? How data crossing can be useful for identification of areas with the higher transmission risk level ?
Automobile Course. Progress Record and Theory Outline.
ERIC Educational Resources Information Center
Connecticut State Dept. of Education, Hartford. Div. of Vocational-Technical Schools.
This combination progress record and course outline is designed for use by individuals teaching a course in automobile repair. Included among the topics addressed in the course are the following: shop safety, engines, fuel and exhaust systems, electrical systems, crankcase lubrication systems, cooling systems, power transmission systems, steering…
National Plant Diagnostic Network, Taxonomic training videos: Introduction to Aphids - Part 2
USDA-ARS?s Scientific Manuscript database
Training is a critical part of aphid (Hemiptera: Aphididae) identification. This video provides visual instruction on important subject areas for aphid regulatory issues. Here the subject of aphids as they relate to disease transmission, biology, identification, and pathways is addressed. Aphid topi...
HIV Prevention Readiness in Undergraduates and Inmates.
ERIC Educational Resources Information Center
Antonio, Michael E.; And Others
Prevention of Human Immunodeficiency Virus (HIV) transmission is increasingly an international priority. Education of high-risk populations, such as incarcerated individuals, is particularly important in thwarting the spread of HIV. To address this concern, the attitudes, beliefs, and knowledge of inmates concerning HIV and AIDS related issues are…
Running TCP/IP over ATM Networks.
ERIC Educational Resources Information Center
Witt, Michael
1995-01-01
Discusses Internet protocol (IP) and subnets and describes how IP may operate over asynchronous transfer mode (ATM). Topics include TCP (transmission control protocol), ATM cells and adaptation layers, a basic architectural model for IP over ATM, address resolution, mapping IP to a subnet technology, and connection management strategy. (LRW)
Airborne transmission of respiratory diseases.
Baker, S A
1995-01-01
In surveys during the past decade, CEs and BMETs have reported an increasing frequency of respiratory illnesses they believed to be acquired as a result of their occupation. These illnesses varied from mild to severe in terms of long-term prognosis. With the increasing numbers of cases of drug-resistant organisms, respiratory infections are a growing concern for healthcare workers, employers, and government officials. Armed with a better knowledge base about symptoms, transmission and prevention, CEs and BMETs will be more aware of potential biohazardous situations and the necessary personal protective measures to be employed. Both the Occupational Safety and Health Administration (OSHA) and the Centers for Disease Control and Prevention (CDCP) have issued guidelines for preventing airborne transmission of infectious diseases. This paper addresses the respiratory illnesses reported by CEs and BMETs as occupational concerns, as well as briefly discussing potential epidemic pulmonary conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhou, Shengru; Hurlbut, David J.; Bird, Lori A.
A strategically planned transmission network is an important source of flexibility for the integration of large-scale renewable energy (RE). Such a network can offer access to a broad geographic diversity of resources, which can reduce flexibility needs and facilitate sharing between neighboring balancing areas. This report builds on two previous NREL technical reports - Advancing System Flexibility for High Penetration Renewable Integration (Milligan et al. 2015) and 'Renewables-Friendly' Grid Development Strategies (Hurlbut et al. 2015) - which discuss various flexibility options and provide an overview of U.S. market models and grid planning. This report focuses on addressing issues with cross-regional/provincialmore » transmission in China with the aim of integrating renewable resources that are concentrated in remote areas and require inter-regional/provincial power exchange.« less
Vibration Propagation in Spider Webs
NASA Astrophysics Data System (ADS)
Hatton, Ross; Otto, Andrew; Elias, Damian
Due to their poor eyesight, spiders rely on web vibrations for situational awareness. Web-borne vibrations are used to determine the location of prey, predators, and potential mates. The influence of web geometry and composition on web vibrations is important for understanding spider's behavior and ecology. Past studies on web vibrations have experimentally measured the frequency response of web geometries by removing threads from existing webs. The full influence of web structure and tension distribution on vibration transmission; however, has not been addressed in prior work. We have constructed physical artificial webs and computer models to better understand the effect of web structure on vibration transmission. These models provide insight into the propagation of vibrations through the webs, the frequency response of the bare web, and the influence of the spider's mass and stiffness on the vibration transmission patterns. Funded by NSF-1504428.
NASA Astrophysics Data System (ADS)
Tompkins, A. M.; Thomson, M. C.
2017-12-01
Simulations of the impact of climate variations on a vector-bornedisease such as malaria are subject to a number of sources ofuncertainty. These include the model structure and parameter settingsin addition to errors in the climate data and the neglect of theirspatial heterogeneity, especially over complex terrain. We use aconstrained genetic algorithm to confront these two sources ofuncertainty for malaria transmission in the highlands of Kenya. Thetechnique calibrates the parameter settings of a process-based,mathematical model of malaria transmission to vary within theirassessed level of uncertainty and also allows the calibration of thedriving climate data. The simulations show that in highland settingsclose to the threshold for sustained transmission, the uncertainty inclimate is more important to address than the malaria modeluncertainty. Applications of the coupled climate-malaria modelling system are briefly presented.
Munro, Jenny; McIntyre, Lynn
2016-01-01
This paper builds on critiques that call for a more nuanced and contextualised understanding of conditions that affect HIV prevention by looking at West Papuan women's experiences of prevention of mother-to-child transmission services. Drawing on qualitative, ethnographic research with indigenous women and health workers, the paper demonstrates that women experience poor-quality HIV education and counselling, and that indigenous practices and concerns are largely not addressed by HIV services. We attribute this to a combination of national anti-indigenous and anti-separatist political concerns with donor-led interventions that result in limited localisation and reduced effectiveness of HIV prevention measures. In West Papua, services are needed that enhance cooperation and shared commitment, and that acknowledge and work to overcome existing inequalities, ethnic tensions and discrimination in the health system. Beyond Indonesia, donor-led HIV programmes and interventions need to balance avoidance of politically sensitive issues with complicity in perpetuating health inequalities. Translating global health interventions and donor priorities into locally compelling HIV prevention activities involves more than navigating local cultural and religious beliefs. Programme development and implementation strategies that entail confronting structural questions as well as social hierarchies, cleavages and silences are needed to render more effective services; strategies that are inherently political.
Neural signals of vicarious extinction learning
Haaker, Jan; Selbing, Ida; Olsson, Andreas
2016-01-01
Social transmission of both threat and safety is ubiquitous, but little is known about the neural circuitry underlying vicarious safety learning. This is surprising given that these processes are critical to flexibly adapt to a changeable environment. To address how the expression of previously learned fears can be modified by the transmission of social information, two conditioned stimuli (CS + s) were paired with shock and the third was not. During extinction, we held constant the amount of direct, non-reinforced, exposure to the CSs (i.e. direct extinction), and critically varied whether another individual—acting as a demonstrator—experienced safety (CS + vic safety) or aversive reinforcement (CS + vic reinf). During extinction, ventromedial prefrontal cortex (vmPFC) responses to the CS + vic reinf increased but decreased to the CS + vic safety. This pattern of vmPFC activity was reversed during a subsequent fear reinstatement test, suggesting a temporal shift in the involvement of the vmPFC. Moreover, only the CS + vic reinf association recovered. Our data suggest that vicarious extinction prevents the return of conditioned fear responses, and that this efficacy is reflected by diminished vmPFC involvement during extinction learning. The present findings may have important implications for understanding how social information influences the persistence of fear memories in individuals suffering from emotional disorders. PMID:27278792
Lessons Learned and Legacy of the Stop Transmission of Polio Program.
Kerr, Yinka; Mailhot, Melinda; Williams, Alford A J; Swezy, Virginia; Quick, Linda; Tangermann, Rudolf H; Ward, Kirsten; Benke, Amalia; Callaghan, Anna; Clark, Kathleen; Emery, Brian; Nix, Jessica; Aydlotte, Eleanor; Newman, Charlotte; Nkowane, Benjamin
2017-07-01
In 1988, the by the World Health Assembly established the Global Polio Eradication Initiative, which consisted of a partnership among the World Health Organization (WHO), Rotary International, the Centers for Disease Control and Prevention (CDC), and the United Nations Children's Fund. By 2016, the annual incidence of polio had decreased by >99.9%, compared with 1988, and at the time of writing, only 3 countries in which wild poliovirus circulation has never been interrupted remain: Afghanistan, Nigeria, and Pakistan. A key strategy for polio eradication has been the development of a skilled and deployable workforce to implement eradication activities across the globe. In 1999, the Stop Transmission of Polio (STOP) program was developed and initiated by the CDC, in collaboration with the WHO, to train and mobilize additional human resources to provide technical assistance to polio-endemic countries. STOP has also informed the development of other public health workforce capacity to support polio eradication efforts, including national STOP programs. In addition, the program has diversified to address measles and rubella elimination, data management and quality, and strengthening routine immunization programs. This article describes the STOP program and how it has contributed to polio eradication by building global public health workforce capacity. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Power from space for use on earth: An emerging global option
NASA Technical Reports Server (NTRS)
Glaser, Peter E.
1989-01-01
The concept of the Earth as a closed ecological system is addressed from the point of view of the availability and use of energy from space and its potential influence on the economies of both developed and developing countries. The results of past studies of the solar power satellite (SPS) are reviewed, and the current international activities exploring various aspects of an SPS are mentioned. The functions of an SPS, including collection of solar energy in orbit, conversion to an intermediate form of energy, transmission of energy from orbit to Earth, and conversion to useful energy in the most appropriate form are discussed. Directions for future developments are addressed including a suggested planning framework. Salient aspects of SPS technologies are presented, and the potential benefits of the uses of lunar materials for the SPS construction are outlined. Scenarios within the context of international participation in a global SPS system are presented. The conclusion is drawn that an SPS system is one of the few promising, globally applicable power generation options that has the potential to meet energy demands in the 21st Century and to achieve the inevitable transition to inexhaustible and renewable energy sources.
Major decrease in malaria transmission on Mayotte Island.
Maillard, Olivier; Lernout, Tinne; Olivier, Sophie; Achirafi, Aboubacar; Aubert, Lydéric; Lepère, Jean François; Thiria, Julien; Pagès, Frédéric; Filleul, Laurent
2015-08-19
Plasmodium falciparum is responsible for most malaria cases on Mayotte Island, in the Comorian Archipelago. Malaria is endemic and a major public health problem in the archipelago with an intense, stable and permanent transmission. This study reports results of 8 years of malaria surveillance from 2007 to 2014 after the strengthening of malaria control activities in Mayotte and the neighbouring islands. Surveillance was based on physicians' reports of malaria cases between January 2007 and December 2014. Malaria cases were confirmed by at least a positive rapid diagnostic test and/or demonstration of Plasmodium sp. in a blood smear. The date, and the patients' age, sex, address, presentation of symptoms, biology, treatment and recent history of travel were collected by verbal questioning during consultation and/or hospitalization. Monthly rainfall data were also compiled during the study period. From 2007 to 2014, 2073 cases were reported on Mayotte Island: 977 imported cases, 807 autochthonous cases and 289 cases of unknown origin. The total malaria annual parasite incidence lowered from 3.0 in 2007 to 0.07 per 1,000 inhabitants in 2014 as the autochthonous malaria incidence decreased from 1.6 to 0.004 per 1,000 inhabitants in the same period and in all age groups. Most of the imported cases came from Comoros (94 %). Severe forms represented approximately 11 % of cases, and only two deaths have been recorded among the imported cases. Approximately 19 % of cases were hospitalized (3 % in an intensive care unit). There is clearly a decrease in malaria transmission in Mayotte since 2007 and the goal of elimination seems more achievable than ever. In 2011, Mayotte entered the elimination phase when P. falciparum API passed under 1 case per 1,000 people at risk. The combination of vector control measures, active surveillance and case management, including effective treatment with artemisinin-based combination therapy, has been essential to achieve a present status of low and decreasing malaria transmission on the island. Mayotte has entered the elimination phase, but some goals remain to be accomplished before a programme re-orientation toward malaria elimination is contemplated. Moreover, a regional management policy is crucial because this would allow control measures to be targeted and based on a regional surveillance-response system rather than isolated.
Qin, Xinyan; Wu, Gongping; Fan, Fei; Ye, Xuhui; Mei, Quanjie
2018-01-01
With the growth of the national economy, there is increasing demand for electricity, which forces transmission line corridors to become structurally complicated and extend to complex environments (e.g., mountains, forests). It is a great challenge to inspect transmission line in these regions. To address these difficulties, a novel method of autonomous inspection for transmission line is proposed based on cable inspection robot (CIR) LiDAR data, which mainly includes two steps: preliminary inspection and autonomous inspection. In preliminary inspection, the position and orientation system (POS) data is used for original point cloud dividing, ground point filtering, and structured partition. A hierarchical classification strategy is established to identify the classes and positions of the abnormal points. In autonomous inspection, CIR can autonomously reach the specified points through inspection planning. These inspection targets are imaged with PTZ (pan, tilt, zoom) cameras by coordinate transformation. The feasibility and effectiveness of the proposed method are verified by test site experiments and actual line experiments, respectively. The proposed method greatly reduces manpower and improves inspection accuracy, providing a theoretical basis for intelligent inspection of transmission lines in the future. PMID:29462865
Ruiz-Fons, F
2017-02-01
Many wild swine populations in different parts of the World have experienced an unprecedented demographic explosion that may result in increased exposure of humans to wild swine zoonotic pathogens. Interactions between humans and wild swine leading to pathogen transmission could come from different ways, being hunters and game professionals the most exposed to acquiring infections from wild swine. However, increasing human settlements in semi-natural areas, outdoor activities, socio-economic changes and food habits may increase the rate of exposure to wild swine zoonotic pathogens and to potentially emerging pathogens from wild swine. Frequent and increasing contact rate between humans and wild swine points to an increasing chance of zoonotic pathogens arising from wild swine to be transmitted to humans. Whether this frequent contact could lead to new zoonotic pathogens emerging from wild swine to cause human epidemics or emerging disease outbreaks is difficult to predict, and assessment should be based on thorough epidemiologic surveillance. Additionally, several gaps in knowledge on wild swine global population dynamics trends and wild swine-zoonotic pathogen interactions should be addressed to correctly assess the potential role of wild swine in the emergence of diseases in humans. In this work, viruses such as hepatitis E virus, Japanese encephalitis virus, Influenza virus and Nipah virus, and bacteria such as Salmonella spp., Shiga toxin-producing Escherichia coli, Campylobacter spp. and Leptospira spp. have been identified as the most prone to be transmitted from wild swine to humans on the basis of geographic spread in wild swine populations worldwide, pathogen circulation rates in wild swine populations, wild swine population trends in endemic areas, susceptibility of humans to infection, transmissibility from wild swine to humans and existing evidence of wild swine-human transmission events. © 2015 Blackwell Verlag GmbH.
Transmission Line Security Monitor
None
2017-12-09
The Transmission Line Security Monitor is a multi-sensor monitor that mounts directly on high-voltage transmission lines to detect, characterize and communicate terrorist activity, human tampering and threatening conditions around support towers. For more information about INL's critical infrastructure protection research, visit http://www.facebook.com/idahonationallaboratory.
Beck, Dano W; Lalota, Marlene; Metsch, Lisa R; Cardenas, Gabriel A; Forrest, David W; Lieb, Spencer; Liberti, Thomas M
2012-04-01
Misconceptions about HIV transmission and prevention may inhibit individuals' accurate assessment of their level of risk. We used venue-based sampling to conduct a cross-sectional study of heterosexually active adults (N = 1,221) within areas exhibiting high poverty and HIV/AIDS rates in Miami-Dade and Broward counties in 2007. Two logistic regression analyses identified correlates of holding inaccurate beliefs about HIV transmission and prevention. Belief in incorrect HIV prevention methods (27.2%) and modes of transmission (38.5%) was common. Having at least one incorrect prevention belief was associated with being Hispanic compared to white (non-Hispanic), being depressed, and not knowing one's HIV status. Having at least one incorrect transmission belief was associated with being younger, heavy alcohol use, being depressed, not having seen a physician in the past 12 months, and not knowing one's HIV status. Among low-income heterosexuals, HIV prevention and transmission myths are widespread. Debunking them could have HIV prevention value.
Kosc, Tanya Z.; Marshall, Kenneth L.; Jacobs, Stephen D.
2004-12-07
Composite or layered flakes having a plurality of layers of different materials, which may be dielectric materials, conductive materials, or liquid crystalline materials suspended in a fluid host and subjected to an electric field, provide optical effects dependent upon the angle or orientation of the flakes in the applied electric field. The optical effects depend upon the composition and thickness of the layers, producing reflectance, interference, additive and/or subtractive color effects. The composition of layered flakes may also be selected to enhance and/or alter the dielectric properties of flakes, whereby flake motion in an electric field is also enhanced and/or altered. The devices are useful as active electro-optical displays, polarizers, filters, light modulators, and wherever controllable polarizing, reflecting and transmissive optical properties are desired.
HIV/AIDS and Infertility: Emerging Problems in the Era of Highly Active Antiretrovirals
Kushnir, Vitaly A.; Lewis, William
2011-01-01
Objective To review the effects of HIV/AIDS, associated co-morbid conditions, and side effects of antiretroviral treatment on fertility. Design A Pubmed computer search was performed to identify relevant articles. Setting Research institution. Intervention(s) None. Result(s) Biological alterations in reproductive physiology may account for sub-fertility in patients infected with HIV. Psychosocial factors in patients with HIV infection may affect reproductive desires and outcomes. Antiretroviral medications may have direct toxicity on gametes and embryos. Available evidence indicates that fertility treatments can be a safe option for HIV-discordant couples; although, potential risk of viral transmission cannot be completely eliminated. Conclusion(s) Reproductive desires are increasingly becoming prominent in the healthcare of young HIV-infected patients. Additional data is needed to address the effect of HIV and its treatments on fertility and reproductive outcomes. PMID:21722892
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Ondrejcak, Tomas; Wang, Qinwen; Kew, James N C; Virley, David J; Upton, Neil; Anwyl, Roger; Rowan, Michael J
2012-02-29
Nicotinic acetylcholine receptors mediate fast cholinergic modulation of glutamatergic transmission and synaptic plasticity. Here we investigated the effects of subtype selective activation of the α7 nicotinic acetylcholine receptors on hippocampal transmission and the inhibition of synaptic long-term potentiation by the Alzheimer's disease associated amyloid ß-protein (Aß). The α7 nicotinic acetylcholine receptor agonist "compound A" ((R)-N-(1-azabicyclo[2.2.2]oct-3-yl)(5-(2-pyridyl))thiophene-2-carboxamide) induced a rapid-onset persistent enhancement of synaptic transmission in the dentate gyrus in vitro. Consistent with a requirement for activation of α7 nicotinic acetylcholine receptors, the type II α7-selective positive allosteric modulator PheTQS ((3aR, 4S, 9bS)-4-(4-methylphenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide) potentiated, and the antagonist methyllycaconitine (MLA) prevented the persistent enhancement. Systemic injection of the agonist also induced a similar MLA-sensitive persistent enhancement of synaptic transmission in the CA1 area in vivo. Remarkably, although compound A did not affect control long-term potentiation (LTP) in vitro, it prevented the inhibition of LTP by Aß1-42 and this effect was inhibited by MLA. These findings strongly indicate that activation of α7 nicotinic acetylcholine receptors is sufficient to persistently enhance hippocampal synaptic transmission and to overcome the inhibition of LTP by Aß. Copyright © 2011 Elsevier B.V. All rights reserved.
Nagpal, B. N.; Gupta, Sanjeev Kumar; Shamim, Arshad; Vikram, Kumar; Srivastava, Aruna; Tuli, N. R.; Saxena, Rekha; Singh, Himmat; Singh, V. P.; Bhagat, V. N.; Yadav, N. K.; Valecha, Neena
2016-01-01
Background and objective The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December–May) months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June–November). The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI), house index (HI), pupal index (PI) and breteau index (BI). Methods A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities. Results Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05). In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (p<0.05) between the study group and control group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as compared to control group where increase of 59%, 102%, 73% and 71% respectively. As a result of reduction in larval indices, no dengue case (except one NS1) was observed in study group, whereas 38 dengue cases were observed in control group. Conclusion Through this pilot study, it is concluded that proper intervention in non-transmission season reduces vector density and subsequently dengue cases in transmission season. PMID:27918577
Nagpal, B N; Gupta, Sanjeev Kumar; Shamim, Arshad; Vikram, Kumar; Srivastava, Aruna; Tuli, N R; Saxena, Rekha; Singh, Himmat; Singh, V P; Bhagat, V N; Yadav, N K; Valecha, Neena
2016-01-01
The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December-May) months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June-November). The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI), house index (HI), pupal index (PI) and breteau index (BI). A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities. Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05). In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (p<0.05) between the study group and control group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as compared to control group where increase of 59%, 102%, 73% and 71% respectively. As a result of reduction in larval indices, no dengue case (except one NS1) was observed in study group, whereas 38 dengue cases were observed in control group. Through this pilot study, it is concluded that proper intervention in non-transmission season reduces vector density and subsequently dengue cases in transmission season.
Transmission of vocational skills between experienced and new hospital workers.
Thébault, Jeanne; Gaudart, Corinne; Cloutier, Esther; Volkoff, Serge
2012-01-01
This article presents the results of a study currently underway looking at the transmission of vocational skills between health care workers in a French hospital. The aim was to show that health care workers, in addition to their work with patients, also have to incorporate the transmission of vocational skills into their daily activities. Thirteen transmission situations were observed and analyzed by means of an activity-focused ergonomic work analysis, with the aim of reporting on this "invisible work". The population studied was composed of nurses and the nursing assistants from three different units in one hospital. The results show that the work required to integrate and supervise new staff members is left to the discretion of health care workers. This means they are constantly required to arbitrate on both an individual and collective basis between providing health care for patients and supporting new members of staff. The content of the transmission goes beyond the prescribed tasks and technical knowledge, as staff members also pass on their professional strategies (individual and collective), rules of practice and ethical considerations. Supervising students also offers experienced workers the opportunity to share their professional practices. This study highlights the issues arising from this transmission activity for the experienced workers, new workers, patients and the hospital.
Wuehler, Sara E; El Hafed Ould Dehah, Cheikh Mohamed
2011-04-01
Progress towards reducing mortality and malnutrition among children <5 years of age has been less than needed to achieve related Millennium Development Goals (MDGs), so several international agencies joined to 'reposition children's right to adequate nutrition in the Sahel', starting with an analysis of current activities related to infant and young child nutrition (IYCN). The main objectives of the situational analysis are to compile, analyse, and interpret available information on infant and child feeding, and the nutrition and health situation of children <2 years of age in Mauritania as one of the six target countries (Burkina Faso, Chad, Mali, Mauritania, Niger, Senegal). These findings are available to assist countries in identifying inconsistencies and filling gaps in current programming. Between August and November of 2008, key informants responsible for conducting IYCN-related activities in Mauritania were interviewed, and 46 documents were examined on the following themes: optimal breastfeeding and complementary feeding practices, prevention of micronutrient deficiencies, prevention of mother-to-child transmission of human immunodeficiency virus (HIV), management of acute malnutrition, food security, and hygienic practices. Mauritania is on track to reaching the MDG of halving undernutrition among children <5 years of age by 2015. National policy documents, training guides, and programmes address nearly all of the key IYCN topics, specifically or generally. Exceptions are the use of zinc supplements in diarrhoea treatment, prevention of zinc deficiency, and dietary guidelines for preventing mother-to-child transmission of HIV. Substantial infrastructure capacity building was also recently implemented in nutritionally high-risk regions, and increases were reported in exclusive breastfeeding rates among children <6 months. The recent National Behaviour Change Communication Strategy is intended to address the needs of adapting programme activities to local needs. Despite these noteworthy accomplishments, the prevalence of acute malnutrition remains high, mortality rates did not decrease as malnutrition rates decreased, the overall prevalence of desirable nutrition-related practices is low, and human resources are reportedly insufficient to carry out all nutrition-related programme activities. Very little nutrition research has been conducted in Mauritania, and key informants identified gaps in adapting international programmes to local needs. Monitoring and evaluation reports have not been rigorous enough to identify which programme activities were implemented as designed or whether programmes were effective at improving nutritional and health status of young children. Therefore, we could not confirm which programmes might have been responsible for the reported improvements, or if other population-wide changes contributed to these changes. The policy framework is supportive of optimal IYCN practices, but greater resources and capacity building are needed to (i) support activities to adapt training materials and programme protocols to fit local needs, (ii) expand and track the implementation of evidence-based programmes nationally, (iii) improve and carry out monitoring and evaluation that identify effective and ineffective programmes, and (iv) apply these findings in developing, disseminating, and improving effective programmes. © 2011 Blackwell Publishing Ltd.
Ahmad, Tasha; Laviolette, Steven R
2017-08-01
The ventral tegmental area (VTA) and its projections to the basolateral amygdala (BLA) and nucleus accumbens (NAc) are critical for cannabinoid-related motivational effects. Cannabinoid CB1 receptor (CB1R) transmission modulates VTA dopamine (DA) neuron activity and previous reports demonstrate anatomically segregated effects of CB1R transmission in the VTA. However, the underlying pharmacological and anatomical regions responsible for these effects are currently unknown. The objective of the study is to characterize the motivational effects of localized anterior vs. posterior intra-VTA activation vs. blockade of CB1R transmission and the potential role of intra-BLA and intra-NAc DA transmission in these phenomena. Using a conditioned place preference (CPP) procedure, we administered a CB1 agonist (WIN-55,212-2) or antagonist (AM 251) into the posterior VTA (pVTA) or anterior VTA (aVTA) of rats, combined with intra-BLA or intra-NAc DA receptor blockade and intra-VTA co-administration of selective mu vs. kappa opiate-receptor antagonists. Intra-pVTA CB1R activation produced robust rewarding effects through a mu-opiate receptor mechanism whereas CB1R blockade produced conditioned place aversions (CPA) through a kappa-opiate receptor substrate. In contrast, modulation of aVTA CB1R transmission produced no observable effects. Intra-BLA DA receptor blockade prevented the rewarding effects of pVTA CB1R activation, but had no effects on CB1R blockade-induced aversions. In contrast, intra-NAc DA receptor blockade selectively blocked the aversive effects of pVTA CB1R antagonism. Activation vs. blockade of CB1R transmission in the posterior VTA produces bivalent rewarding or aversive effects through separate mu vs. kappa-opiate receptor substrates. These dissociable effects depend on separate DA receptor transmission substrates in the BLA or NAc, respectively.
Croft, Wayne; Dobson, Katharine L; Bellamy, Tomas C
2015-01-01
The capacity of synaptic networks to express activity-dependent changes in strength and connectivity is essential for learning and memory processes. In recent years, glial cells (most notably astrocytes) have been recognized as active participants in the modulation of synaptic transmission and synaptic plasticity, implicating these electrically nonexcitable cells in information processing in the brain. While the concept of bidirectional communication between neurons and glia and the mechanisms by which gliotransmission can modulate neuronal function are well established, less attention has been focussed on the computational potential of neuron-glial transmission itself. In particular, whether neuron-glial transmission is itself subject to activity-dependent plasticity and what the computational properties of such plasticity might be has not been explored in detail. In this review, we summarize current examples of plasticity in neuron-glial transmission, in many brain regions and neurotransmitter pathways. We argue that induction of glial plasticity typically requires repetitive neuronal firing over long time periods (minutes-hours) rather than the short-lived, stereotyped trigger typical of canonical long-term potentiation. We speculate that this equips glia with a mechanism for monitoring average firing rates in the synaptic network, which is suited to the longer term roles proposed for astrocytes in neurophysiology.
Progress toward poliomyelitis eradication - Nigeria, January 2011-September 2012.
2012-11-09
In 1988, the World Health Assembly launched the Global Polio Eradication Initiative (GPEI) and, in 2012, declared the completion of polio eradication a programmatic emergency for global public health. To date, wild poliovirus (WPV) cases reported worldwide in 2012 are at historically low levels. Nigeria is one of only three countries with uninterrupted WPV transmission (in addition to Pakistan and Afghanistan) and has been the origin of WPV imported into 25 previously polio-free countries since 2003. This report updates previous reports and describes polio eradication activities and progress in Nigeria during January 2011-September 2012, as of October 30, 2012. The number of reported WPV cases increased from 21 in 2010 to 62 in 2011. During January-September 2012, a total of 99 WPV cases were reported, more than doubling from the 42 cases reported during the same period in 2011. During 2011, a total of 32 circulating vaccine-derived polio virus type 2 (cVDPV2) cases were confirmed; six cVDPV2 cases were confirmed during January-September 2012, compared with 18 cVDPV2 cases during the same period in 2011. Nigeria's 2012 Polio Eradication Emergency Plan includes senior government leadership oversight, new program management and strategic initiatives, an accountability framework, and a surge in human resources to address chronically missed children during supplemental immunization activities (SIAs).* In 2012, indicators of immunization campaign quality show modest improvements; available data indicate gaps in surveillance. Continuing WPV transmission in Nigeria poses an ongoing risk for WPV reintroduction and outbreaks in polio-free countries and is a major obstacle to achieving global eradication.
Ma, Liang; Su, Wei; Liu, Jian-Xin; Zeng, Xiao-Xi; Huang, Zhi; Li, Wen; Liu, Zheng-Chun; Tang, Jian-Xin
2017-08-01
The present study addresses an eco-friendly and energy-saving method for extracellular biosynthesis of silver nanoparticles (AgNPs) using a cell free filtrate of the fungus strain Penicillium aculeatum Su1 as a reducing agent. Parametric optimization of the biosynthesis process demonstrated different effects on the size, distribution, yield, and synthesis rate of biosynthesized AgNPs. The transmission electron microscopy (TEM) measurements demonstrated that AgNPs were spherical or approximately spherical, with a size between 4 and 55nm. High-resolution transmission electron microscopy (HR-TEM) and X-ray diffraction (XRD) analyses indicated that AgNPs were nanocrystalline by nature, with the character of a face-centered cubic (fcc). Fourier transform infrared spectroscopy (FTIR) analysis confirmed the existence of protein molecules that acted as a reducing agent and a capping agent during the biosynthesis process. Furthermore, the biosynthesized AgNPs exhibited higher antimicrobial activity than silver ions against Gram negative bacteria, Gram positive bacteria and fungi. Compared with silver ions, the biosynthesized AgNPs presented higher biocompatibility toward human bronchial epithelial (HBE) cells and high cytotoxicity in a dose-dependent manner with an IC 50 of 48.73μg/mL toward A549 cells. These results demonstrate that Penicillium aculeatum Su1 is a potential bioresource that can be used to produce low-cost and eco-friendly AgNPs as efficient antimicrobial agent, drug delivery vehicle or anticancer drug for clinic treatment. Copyright © 2017 Elsevier B.V. All rights reserved.
Essays on electricity transmission investment and financial transmission rights
NASA Astrophysics Data System (ADS)
Shang, Wenzhuo
The U.S. electric power industry has been going through fundamental restructuring and realignment since the 1990's. Many issues and problems have emerged during the transition, and both economists and engineers have been looking for the solutions fervently. In this dissertation, which consists primarily of three essays, we apply economics theory and techniques to the power industry and address two related issues, transmission investment and financial transmission rights (FTRs). The first essay takes the decentralized perspective and investigates the efficiency attribute of market-based transmission investment under perfect competition. We clarify, for the first time, the nature of the externality created by loop flows that causes transmission investment to be inefficient. Our findings have important implications for better understanding of transmission market design and creating incentives for efficient transmission investment. In the second essay, we define several rules for allocating transmission investment cost within the framework of cooperative game theory. These rules provide fair, stable or efficient cost allocations in theory and are good benchmarks against which the allocation mechanism in practice can be compared and improved upon. In the last essay, we make exploratory efforts in analyzing and assessing empirically the performance of the Midwest independent system operator (MISO) FTR auction market. We reveal some stylized facts about this young market and find that it is not efficient under the risk-neutrality assumption. We also point out and correct the drawbacks in previous related work and suggest about more complete empirical work in future. In all, this dissertation makes both theoretic and empirical analysis of the two hot issues related to the power industry and comes up with findings that have important implications for the development of this industry.
Whole-genome sequencing to determine Neisseria gonorrhoeae transmission: an observational study
Cole, Kevin; Cole, Michelle J; Cresswell, Fiona; Dean, Gillian; Dave, Jayshree; Thomas, Daniel Rh; Foster, Kirsty; Waldram, Alison; Wilson, Daniel J; Didelot, Xavier; Grad, Yonatan H; Crook, Derrick W; Peto, Tim EA; Walker, A Sarah
2016-01-01
Background New approaches are urgently required to address increasing rates of gonorrhoea and the emergence and global spread of antibiotic-resistant Neisseria gonorrhoeae. Whole genome sequencing (WGS) can be applied to study transmission and track resistance. Methods We performed WGS on 1659 isolates from Brighton, UK, and 217 additional isolates from other UK locations. We included WGS data (n=196) from the USA. Estimated mutation rates, plus diversity observed within patients across anatomical sites and probable transmission pairs, were used to fit a coalescent model to determine the number of single nucleotide polymorphisms (SNPs) expected between sequences related by direct/indirect transmission, depending on the time between samples. Findings We detected extensive local transmission. 281/1061(26%) Brighton cases were indistinguishable (0 SNPs) to ≥1 previous case(s), and 786(74%) had evidence of a sampled direct or indirect Brighton source. There was evidence of sustained transmission of some lineages. We observed multiple related samples across geographic locations. Of 1273 infections in Brighton, 225(18%) were linked to another case from elsewhere in the UK, and 115(9%) to a case from the USA. Four lineages initially identified in Brighton could be linked to 70 USA sequences, including 61 from a lineage carrying the mosaic penA XXXIV associated with reduced cefixime susceptibility. Interpretation We present a WGS-based tool for genomic contact tracing of N. gonorrhoeae and demonstrate local, national and international transmission. WGS can be applied across geographical boundaries to investigate gonorrhoea transmission and to track antimicrobial resistance. Funding Oxford NIHR Health Protection Research Unit and Biomedical Research Centre. PMID:27427203
48 CFR 552.216-73 - Ordering Information.
Code of Federal Regulations, 2010 CFR
2010-10-01
... transmission or □ computer-to-computer Electronic Data Interchange (EDI). (b) An offeror electing to receive computer-to-computer EDI is requested to indicate below the name, address, and telephone number of the representative to be contacted regarding establishment of an EDI interface. (c) An offeror electing to receive...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piekarski, D.; Brad, D.
This report is about a work effort where the overall objectives were to establish a methodology and approach for selected transmission and distribution (T&D) grid modernization; monitor the results; and report on the findings, recommendations, and lessons learned. The work reported addressed T&D problems and solutions, related reliability issues, equipment and operation upgrades, and respective field testing.
HIV Prevention and AIDS Education: Resources for Special Educators.
ERIC Educational Resources Information Center
Byrom, Elizabeth, Ed.; Katz, Ginger, Ed.
This guide was developed out of a 5-year project aimed at preventing the transmission of the human immunodeficiency virus (HIV) by promoting HIV prevention and AIDS (acquired immunodeficiency syndrome) education in school health programs. This document includes recommendations of a January, 1989 forum which addressed HIV prevention education for…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-29
... encryption of data for storage and transmission, network protection and intrusion detection, and cyber... review of its unclassified network for evidence of intrusion to include, but is not limited to... DoD information within industry, nor does it address cyber intrusion reporting for that information...
Women and HIV Disease: An Emerging Social Crisis.
ERIC Educational Resources Information Center
Stuntzner-Gibson, Denise
1991-01-01
Addresses major social issues faced by women with human immunodeficiency virus (HIV) disease and explores gender differences in HIV transmission, disease progression, and diagnosis. Discusses how women's sexuality and reproductive rights are affected. Examines specific issues regarding HIV-infected women who use intravenous drugs, women of color,…
Hermance, Meghan E.
2015-01-01
ABSTRACT Powassan virus (POWV) is an encephalitic tick-borne flavivirus which can result in serious neuroinvasive disease with up to a 10% case fatality rate. The study objective was to determine whether the salivary gland extract (SGE) from Ixodes scapularis ticks facilitates the transmission and dissemination of POWV in a process known as saliva-activated transmission. Groups of BALB/c mice were footpad inoculated with either a high dose of POWV with and without SGE or a low dose of POWV with and without SGE. Mice from each group were sacrificed daily. Organ viral loads and gene expression profiles were evaluated by quantitative real-time PCR. Both groups of mice infected with high-dose POWV showed severe neurological signs of disease preceding death. The presence of SGE did not affect POWV transmission or disease outcome for mice infected with the high dose of POWV. Neuroinvasion, paralysis, and death occurred for all mice infected with the low dose of POWV plus SGE; however, for mice infected with the low dose of POWV in the absence of SGE, there were no clinical signs of infection and no mice succumbed to disease. Although this group displayed low-level viremias, all mice were completely healthy, and it was the only group in which POWV was cleared from the lymph nodes. We conclude that saliva-activated transmission occurs in mice infected with a low dose of POWV. Our study is the first to demonstrate virus dose-dependent saliva-activated transmission, warranting further investigation of the specific salivary factors responsible for enhancing POWV transmission. IMPORTANCE Powassan virus (POWV) is a tick-borne flavivirus that continues to emerge in the United States, as is evident by the surge in number and expanding geographic range of confirmed cases in the past decade. This neuroinvasive virus is transmitted to humans by infected tick bites. Successful tick feeding is facilitated by a collection of pharmacologically active factors in tick saliva. In a process known as saliva-activated transmission, tick bioactive salivary molecules are thought to modulate the host environment, making it more favorable for the transmission and establishment of a pathogen. This phenomenon has been demonstrated for several tick-borne pathogens; however, a systematic investigation of the role of tick saliva on dissemination and pathogenesis of a tick-borne viral disease has never been attempted before. This study will fill that gap by systematically examining whether the presence of tick saliva contributes to the transmission and dissemination of POWV in mice. PMID:25995246
Hermance, Meghan E; Thangamani, Saravanan
2015-08-01
Powassan virus (POWV) is an encephalitic tick-borne flavivirus which can result in serious neuroinvasive disease with up to a 10% case fatality rate. The study objective was to determine whether the salivary gland extract (SGE) from Ixodes scapularis ticks facilitates the transmission and dissemination of POWV in a process known as saliva-activated transmission. Groups of BALB/c mice were footpad inoculated with either a high dose of POWV with and without SGE or a low dose of POWV with and without SGE. Mice from each group were sacrificed daily. Organ viral loads and gene expression profiles were evaluated by quantitative real-time PCR. Both groups of mice infected with high-dose POWV showed severe neurological signs of disease preceding death. The presence of SGE did not affect POWV transmission or disease outcome for mice infected with the high dose of POWV. Neuroinvasion, paralysis, and death occurred for all mice infected with the low dose of POWV plus SGE; however, for mice infected with the low dose of POWV in the absence of SGE, there were no clinical signs of infection and no mice succumbed to disease. Although this group displayed low-level viremias, all mice were completely healthy, and it was the only group in which POWV was cleared from the lymph nodes. We conclude that saliva-activated transmission occurs in mice infected with a low dose of POWV. Our study is the first to demonstrate virus dose-dependent saliva-activated transmission, warranting further investigation of the specific salivary factors responsible for enhancing POWV transmission. Powassan virus (POWV) is a tick-borne flavivirus that continues to emerge in the United States, as is evident by the surge in number and expanding geographic range of confirmed cases in the past decade. This neuroinvasive virus is transmitted to humans by infected tick bites. Successful tick feeding is facilitated by a collection of pharmacologically active factors in tick saliva. In a process known as saliva-activated transmission, tick bioactive salivary molecules are thought to modulate the host environment, making it more favorable for the transmission and establishment of a pathogen. This phenomenon has been demonstrated for several tick-borne pathogens; however, a systematic investigation of the role of tick saliva on dissemination and pathogenesis of a tick-borne viral disease has never been attempted before. This study will fill that gap by systematically examining whether the presence of tick saliva contributes to the transmission and dissemination of POWV in mice. Copyright © 2015, Hermance and Thangamani.
NASA Astrophysics Data System (ADS)
Cakoni, Fioralba; Haddar, Houssem
2013-10-01
In inverse scattering theory, transmission eigenvalues can be seen as the extension of the notion of resonant frequencies for impenetrable objects to the case of penetrable dielectrics. The transmission eigenvalue problem is a relatively late arrival to the spectral theory of partial differential equations. Its first appearance was in 1986 in a paper by Kirsch who was investigating the denseness of far-field patterns for scattering solutions of the Helmholtz equation or, in more modern terminology, the injectivity of the far-field operator [1]. The paper of Kirsch was soon followed by a more systematic study by Colton and Monk in the context of developing the dual space method for solving the inverse scattering problem for acoustic waves in an inhomogeneous medium [2]. In this paper they showed that for a spherically stratified media transmission eigenvalues existed and formed a discrete set. Numerical examples were also given showing that in principle transmission eigenvalues could be determined from the far-field data. This first period of interest in transmission eigenvalues was concluded with papers by Colton et al in 1989 [3] and Rynne and Sleeman in 1991 [4] showing that for an inhomogeneous medium (not necessarily spherically stratified) transmission eigenvalues, if they existed, formed a discrete set. For the next seventeen years transmission eigenvalues were ignored. This was mainly due to the fact that, with the introduction of various sampling methods to determine the shape of an inhomogeneous medium from far-field data, transmission eigenvalues were something to be avoided and hence the fact that transmission eigenvalues formed at most a discrete set was deemed to be sufficient. In addition, questions related to the existence of transmission eigenvalues or the structure of associated eigenvectors were recognized as being particularly difficult due to the nonlinearity of the eigenvalue problem and the special structure of the associated transmission eigenvalue problem. The need to answer these questions became important after a series of papers by Cakoni et al [5], and Cakoni et al [6] suggesting that these transmission eigenvalues could be used to obtain qualitative information about the material properties of the scattering object from far-field data. The first answer to the existence of transmission eigenvalues in the general case was given in 2008 when Päivärinta and Sylvester showed the existence of transmission eigenvalues for the index of refraction sufficiently large [7] followed in 2010 by the paper of Cakoni et al who removed the size restriction on the index of refraction [8]. More importantly, in the latter it was shown that transmission eigenvalues yielded qualitative information on the material properties of the scattering object and Cakoni et al established in [9] that transmission eigenvalues could be determined from the Tikhonov regularized solution of the far-field equation. Since the appearance of these papers there has been an explosion of interest in the transmission eigenvalue problem (we refer the reader to our recent survey paper [10] for a detailed account of the developments in this field up to 2012) and the papers in this special issue are representative of the myriad directions that this research has taken. Indeed, we are happy to see that many open theoretical and numerical questions raised in [10] have been answered (totally or partially) in the contributions of this special issue: the existence of transmission eigenvalues with minimal assumptions on the contrast, the numerical evaluation of transmission eigenvalues, the inverse spectral problem, applications to non-destructive testing, etc. In addition to these topics, many other new investigations and research directions have been proposed as we shall see in the brief content summary below. A number of papers in this special issue are concerned with the question of existence of transmission eigenvalues and the structure of the associated transmission eigenfunctions. The three papers by respectively Robbiano [11], Blasten and Päivärinta [12], and Lakshtanov and Vainberg [13] provide new complementary results on the existence of transmission eigenvalues for the scalar problem under weak assumptions on the (possibly complex valued) refractive index that mainly stipulates that the contrast does not change sign on the boundary. It is interesting here to see three different new methods to obtain these results. On the other hand, the paper by Bonnet-Ben Dhia and Chesnel [14] addresses the Fredholm properties of the interior transmission problem when the contrast changes sign on the boundary, exhibiting cases where this property fails. Using more standard approaches, the existence and structure of transmission eigenvalues are analyzed in the paper by Delbary [15] for the case of frequency dependent materials in the context of Maxwell's equations, whereas the paper by Vesalainen [16] initiates the study of the transmission eigenvalue problem in unbounded domains by considering the transmission eigenvalues for Schrödinger equation with non-compactly supported potential. The paper by Monk and Selgas [17] addresses the case where the dielectric is mounted on a perfect conductor and provides some numerical examples of the localization of associated eigenvalues using the linear sampling method. A series of papers then addresses the question of localization of transmission eigenvalues and the associated inverse spectral problem for spherically stratified media. More specifically, the paper by Colton and Leung [18] provides new results on complex transmission eigenvalues and a new proof for uniqueness of a solution to the inverse spectral problem, whereas the paper by Sylvester [19] provides sharp results on how to locate all the transmission eigenvalues associated with angular independent eigenfunctions when the index of refraction is constant. The paper by Gintides and Pallikarakis [20] investigates an iterative least square method to identify the spherically stratified index of refraction from transmission eigenvalues. On the characterization of transmission eigenvalues in terms of far-field measurements, a promising new result is obtained by Kirsch and Lechleiter [21] showing how one can identify the transmission eigenvalues using the eigenvalues of the scattering operator which are available in terms of measured scattering data. In the paper by Kleefeld [22], an accurate method for computing transmission eigenvalues based on a surface integral formulation of the interior transmission problem and numerical methods for nonlinear eigenvalue problems is proposed and numerically validated for the scalar problem in three dimensions. On the other hand, the paper by Sun and Xu [23] investigates the computation of transmission eigenvalues for Maxwell's equations using a standard iterative method associated with a variational formulation of the interior transmission problem with an emphasis on the effect of anisotropy on transmission eigenvalues. From the perspective of using transmission eigenvalues in non-destructive testing, the paper by Cakoni and Moskow [24] investigates the asymptotic behavior of transmission eigenvalues with respect to small inhomogeneities. The paper by Nakamura and Wang [25] investigates the linear sampling method for the time dependent heat equation and analyses the interior transmission problem associated with this equation. Finally, in the paper by Finch and Hickmann [26], the spectrum of the interior transmission problem is related to the unique determination of the acoustic properties of a body in thermoacoustic imaging. We hope that this collection of papers will stimulate further research in the rapidly growing area of transmission eigenvalues and inverse scattering theory.
NASA Astrophysics Data System (ADS)
Fradi, Aniss
The ability to allocate the active power (MW) loading on transmission lines and transformers, is the basis of the "flow based" transmission allocation system developed by the North American Electric Reliability Council. In such a system, the active power flows must be allocated to each line or transformer in proportion to the active power being transmitted by each transaction imposed on the system. Currently, this is accomplished through the use of the linear Power Transfer Distribution Factors (PTDFs). Unfortunately, no linear allocation models exist for other energy transmission quantities, such as MW and MVAR losses, MVAR and MVA flows, etc. Early allocation schemes were developed to allocate MW losses due to transactions to branches in a transmission system, however they exhibited diminished accuracy, since most of them are based on linear power flow modeling of the transmission system. This thesis presents a new methodology to calculate Energy Transaction Allocation factors (ETA factors, or eta factors), using the well-known process of integration of a first derivative function, as well as consistent and well-established mathematical and AC power flow models. The factors give a highly accurate allocation of any non-linear system quantity to transactions placed on the transmission system. The thesis also extends the new ETA factors calculation procedure to restructure a new economic dispatch scheme where multiple sets of generators are economically dispatched to meet their corresponding load and their share of the losses.
Zika Virus: Common Questions and Answers.
Igbinosa, Irogue I; Rabe, Ingrid B; Oduyebo, Titilope; Rasmussen, Sonja A
2017-04-15
Since local mosquito-borne transmission of Zika virus was first reported in Brazil in early 2015, the virus has spread rapidly, with active transmission reported in at least 61 countries and territories worldwide, including the United States. Zika virus infection during pregnancy is a cause of microcephaly and other severe brain anomalies. The virus is transmitted primarily through the bite of an infected Aedes mosquito, but other routes of transmission include sexual, mother-to-fetus during pregnancy, mother-to-infant at delivery, laboratory exposure, and, possibly, transfusion of blood products. Most persons with Zika virus infection are asymptomatic or have only mild symptoms; hospitalizations and deaths are rare. When symptoms are present, maculopapular rash, fever, arthralgia, and conjunctivitis are most common. Zika virus testing is recommended for persons with possible exposure (those who have traveled to or live in an area with active transmission, or persons who had sex without a condom with a person with possible exposure) if they have symptoms consistent with Zika virus disease. Testing is also recommended for pregnant women with possible exposure, regardless of whether symptoms are present. Treatment is supportive, and no vaccine is currently available. The primary methods of prevention include avoiding bites of infected Aedes mosquitoes and reducing the risk of sexual transmission. Pregnant women should not travel to areas with active Zika virus transmission, and men and women who are planning to conceive in the near future should consider avoiding nonessential travel to these areas. Condoms can reduce the risk of sexual transmission.
Tarter, Ralph E; Kirisci, Levent; Kirillova, Galina; Reynolds, Maureen; Gavaler, Judy; Ridenour, Ty; Horner, Michelle; Clark, Duncan; Vanyukov, Michael
2013-01-01
Research has shown involvement of hormones of the hypothalamic pituitary adrenal (HPA) axis and hypothalamic pituitary gonadal (HPG) axis in the regulation of behaviors that contribute to SUD risk and its intergenerational transmission. Neighborhood environment has also been shown to relate to hormones of these two neuroendocrine systems and behaviors associated with SUD liability. Accordingly, it was hypothesized that (1) parental SUD severity and neighborhood quality correlate with activity of the HPG axis (testosterone level) and HPA axis (cortisol stability), and (2) transmissible risk during childhood mediates these hormone variables on development of SUD measured in adulthood. Transmissible risk for SUD measured by the transmissible liability index (TLI; Vanyukov et al., 2009) along with saliva cortisol and plasma testosterone were prospectively measured in boys at ages 10-12 and 16. Neighborhood quality was measured using a composite score encompassing indicators of residential instability and economic disadvantage. SUD was assessed at age 22. Neither hormone variable cross-sectionally correlated with transmissible risk measured at ages 10-12 and 16. However, the TLI at age 10-12 predicted testosterone level and cortisol stability at age 16. Moreover, testosterone level, correlated with cortisol stability at age 16, predicted SUD at age 22. HPA and HPG axes activity do not underlie variation in TLI, however, high transmissible risk in childhood predicts neuroendocrine system activity presaging development of SUD. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
76 FR 52956 - Proposed Information Collection Activity; Comment Request
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2011-08-24
... (HPBS) Transmission File Layouts for HPBS Work Measures OMB No.: 0970-0230 Description: There is no... provide us less precise information on States' performance. The Transmission File Layouts form provides... requested to transmit similar files. We are not requesting any changes to the Transmission File Layouts form...
77 FR 58116 - Commission Information Collection Activities (FERC-732); Comment Request; Extension
Federal Register 2010, 2011, 2012, 2013, 2014
2012-09-19
... Rate Schedules and Tariffs: Long-Term Firm Transmission Rights in Organized Electricity Markets. DATES... Tariffs: Long-Term Firm Transmission Rights in Organized Electricity Markets. OMB Control No.:1902-0245... organized electricity markets to make available long-term firm transmission rights that satisfy each of the...
77 FR 73630 - Commission Information Collection Activities (FERC-732); Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-11
... Transmission Rights in Organized Electricity Markets) to the Office of Management and Budget (OMB) for review... Firm Transmission Rights in Organized Electricity Markets. OMB Control No.: 1902-0245. Type of Request... or more organized electricity markets to make available long-term firm transmission rights that...
Francisella tularensis: an arthropod-borne pathogen
Petersen, Jeannine M.; Mead, Paul S.; Schriefer, Martin E.
2009-01-01
Arthropod transmission of tularemia occurs throughout the northern hemisphere. Few pathogens show the adaptability of Francisella tularensis to such a wide array of arthropod vectors. Nonetheless, arthropod transmission of F. tularensis was last actively investigated in the first half of the 20th century. This review will focus on arthropod transmission to humans with respect to vector species, modes of transmission, geographic differences and F. tularensis subspecies and clades. PMID:18950590
A Global Survey of ATPase Activity in Plasmodium falciparum Asexual Blood Stages and Gametocytes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ortega, Corrie; Frando, Andrew; Webb-Robertson, Bobbie-Jo
Effective malaria control and elimination in hyperendemic areas of the world will require treatment of disease-causing Plasmodium falciparum (Pf) blood stage infection but also blocking parasite transmission from humans to mosquito to prevent disease spread. Numerous antimalarial drugs have become ineffective due to parasite drug resistance and many currently used therapies do not kill gametocytes, highly specialized sexual parasite stages with distinct physiology that are necessary for transmission from the human host to the mosquito vector. Further confounding next generation drug development against Pf is the lack of known biochemical activity for most parasite gene products as well as themore » unknown metabolic needs of non-replicating gametocyte. Here, we take a systematic activity-based proteomics approach to survey the large and druggable ATPase family that is associated with replicating blood stage asexual parasites and transmissible gametocytes. We experimentally confirm existing annotation and predict ATPase function for 38 uncharacterized proteins. ATPase activity broadly changes during the transition from asexual schizonts to gametocytes, indicating altered metabolism and regulatory roles of ATPases specific for each lifecycle stage. By mapping the activity of ATPases associated with gametocytogenesis, we assign biochemical activity to a large number of uncharacterized proteins and identify new candidate transmission blocking targets.« less
A wireless power transmission system for an active capsule endoscope for colon inspection.
Jia, Zhiwei; Yan, Guozheng; Shi, Yu; Zhu, Bingquan
2012-07-01
Multipurpose active capsule endoscopes (ACE) have drawn considerable attention in recent years, but these devices continue to suffer from energy limitations. In order to deliver stable and sufficient energy safely, a wireless power transmission system based on inductive coupling is presented. The system consists of a double-layer solenoid pair primary coil outside and a multiple secondary coils inside the body. At least 500 mW usable power can be transmitted under the worst geometrical conditions and the safety restraints in a volume of Φ13 × 13 mm. The wireless power transmission system is integrated to an ACE and applied in animal experiments. The designed wireless power transmission is proved to be feasible and potentially safe in a future application.
Yanovsky, Inessa; Finkin-Groner, Efrat; Zaikin, Andrey; Lerman, Lena; Shalom, Hila; Zeeli, Shani; Weill, Tehilla; Ginsburg, Isaac; Nudelman, Abraham; Weinstock, Marta
2012-12-13
The cascade of events that occurs in Alzheimer's disease involving oxidative stress and the reduction in cholinergic transmission can be better addressed by multifunctional drugs than cholinesterase inhibitors alone. For this purpose, we prepared a large number of derivatives of indoline-3-propionic acids and esters. They showed scavenging activity against different radicals in solution and significant protection against cytotoxicity in cardiomyocytes and primary cultures of neuronal cells exposed to H2O2 species and serum deprivation at concentrations ranging from 1 nM to 10 μM depending on the compound. For most of the indoline-3-propionic acid derivatives, introduction of N-methyl-N-ethyl or N-methyl-N-(4-methoxyphenyl) carbamate moieties at positions 4, 6, or 7 conferred both acetyl (AChE) and butyryl (BuChE) cholinesterase inhibitory activities at similar concentrations to those that showed antioxidant activity. The most potent AChE inhibitors were 120 (3-(2-aminoethyl) indolin-4-yl ethyl(methyl)carbamate dihydrochloride) and 94 (3-(3-methoxy-3-oxopropyl)-4-(((4-methoxyphenyl)(methyl) carbamoyl)oxy)indolin-1-ium hydrochloride) with IC50s of 0.4 and 1.2 μM, respectively.
HIV prevention in Africa: programs and populations served by non-governmental organizations.
Benotsch, Eric G; Stevenson, L Yvonne; Sitzler, Cheryl A; Kelly, Jeffrey A; Makhaye, Gethwana; Mathey, Eric Dodji; Somlai, Anton M; Brown, Kevin D; Amirkhanian, Yuri; Fernandez, M Isabel; Opgenorth, Karen M
2004-08-01
The AIDS epidemic in Africa remains an urgent health crisis. Non-governmental organizations (NGOs) in Africa play a critical role in the delivery of HIV prevention services and assistance to persons living with AIDS. African NGOs are conducting numerous HIV prevention programs with several at-risk populations, yet their efforts have only rarely been systematically documented. To address this gap in the literature, the authors surveyed one NGO in each of 29 African countries regarding their HIV prevention activities and populations served. This report provides details concerning HIV prevention activities across the continent and describes in detail innovative programs from Togo and South Africa. NGOs in the present sample operate with modest budgets and small staff sizes, yet conduct programs that reach large segments of their communities. NGOs were most likely to report community-level interventions such as peer-education or community outreach. Faced with an epidemic where the main transmission occurs via heterosexual activity, African NGOs were most likely to direct their attention to the general public and to youth. NGOs in Africa are struggling to implement sustainable, cost-effective programs with few resources. Strengthening the infrastructure and capacity of these key agencies is crucial to fighting the AIDS epidemic in Africa.
Thompson, Kimberly M; Duintjer Tebbens, Radboud J
2017-07-01
Recent detections of circulating serotype 2 vaccine-derived poliovirus in northern Nigeria (Borno and Sokoto states) and Pakistan (Balochistan Province) and serotype 1 wild poliovirus in Pakistan, Afghanistan, and Nigeria (Borno) represent public health emergencies that require aggressive response. We demonstrate the importance of undervaccinated subpopulations, using an existing dynamic poliovirus transmission and oral poliovirus vaccine evolution model. We review the lessons learned during the polio endgame about the role of subpopulations in sustaining transmission, and we explore the implications of subpopulations for other vaccine-preventable disease eradication efforts. Relatively isolated subpopulations benefit little from high surrounding population immunity to transmission and will sustain transmission as long as they do not attain high vaccination coverage. Failing to reach such subpopulations with high coverage represents the root cause of polio eradication delays. Achieving and maintaining eradication requires addressing the weakest links, which includes immunizing populations in insecure areas and/or with disrupted or poor-performing health systems and managing the risks of individuals with primary immunodeficiencies who can excrete vaccine-derived poliovirus long-term. Eradication efforts for vaccine-preventable diseases need to create performance expectations for countries to immunize all people living within their borders and maintain high coverage with appropriate interventions.Keywords. Polio; eradication; transmission; heterogeneity. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Cézilly, Frank; Perrot-Minnot, Marie-Jeanne; Rigaud, Thierry
2014-01-01
Several parasite species are known to manipulate the phenotype of their hosts in ways that enhance their own transmission. Co-occurrence of manipulative parasites, belonging to the same species or to more than one species, in a single host has been regularly observed. Little is known, however, on interactions between co-occurring manipulative parasites with same or different transmission routes. Several models addressing this problem have provided predictions on how cooperation and conflict between parasites could emerge from multiple infections. Here, we review the empirical evidence in favor of the existence of synergistic or antagonistic interactions between co-occurring parasites, and highlight the neglected role of micro-organisms. We particularly discuss the actual importance of selective forces shaping the evolution of interactions between manipulative parasites in relation to parasite prevalence in natural populations, efficiency in manipulation, and type of transmission (i.e., horizontal versus vertical), and we emphasize the potential for future research.
Financial Stylized Facts in the Word of Mouth Model
NASA Astrophysics Data System (ADS)
Misawa, Tadanobu; Watanabe, Kyoko; Shimokawa, Tetsuya
Recently, we proposed an agent-based model called the word of mouth model to analyze the influence of an information transmission process to price formation in financial markets. Especially, the short-term predictability of asset return was focused on and an explanation in the view of information transmission was provided to the question why the predictability was much clearly observed in the small-sized stocks. This paper, to extend the previous study, demonstrates that the word of mouth model also has a consistency with other important financial stylized facts. This strengthens the possibility that the information transmission among investors plays a crucial role in price formation. Concretely, this paper addresses two famous statistical features of returns; the leptokurtic distribution of return and the autocorrelation of return volatility. The reasons why these statistical facts receive especial attentions of researchers among financial stylized facts are their statistical robustness and practical importance, such as the applications to the derivative pricing problems.
[Parasitic zoonotic disease agents in human and animal drinking water].
Karanis, P
2000-08-01
Human- and veterinary important parasites of the subkingdom of protozoans and helminths infect humans and animals by ingestion of parasites in contaminated water. The parasites are excreted from the body of infected humans, livestock, zoo animals, companion animals or wild animals in the feces. Recreational waters, agricultural practices and wild animals serve as vehicles of transmission of the parasites in the water supplies. The following topics are addressed: a) the life cycles of parasitic diseases-causing agents with proven or potential transmission via water b) the development and the current research status of the analytical techniques for the detection of parasitic diseases-causing agents from water c) the occurrence of Cryptosporidium and Giardia in surface water supplies and in treated water d) the possible water sources and transmission ways of the parasites into the water supplies e) the behaviour and the possibilities for the removal or elimination of the parasites by water treatment.
NASA Astrophysics Data System (ADS)
Billingham, J.; Benford, James
We advocate international consultations on societal and technical issues to address the risk of Messaging to Extraterrestrial Intelligence (METI) transmissions, and a moratorium on future transmissions until such issues are resolved. Instead, we recommend continuing to conduct SETI by listening, with no innate risk, while using powerful new search systems to give a better total probability of detection of beacons and messages than METI for the same cost, and with no need for a long obligatory wait for a response. Realistically, beacons are costly. In light of recent work on the economics of contact by radio, we offer alternatives to the current standard methods of SETI searches. METI transmissions to date are faint and very unlikely to be detected, even by nearby stars. We show that historical leakage from Earth has been undetectable for Earth-scale receiver systems. Future space microwave and laser power systems will likely be more detectable.
Urbanization, malaria transmission and disease burden in Africa
Hay, Simon I.; Guerra, Carlos A.; Tatem, Andrew J.; Atkinson, Peter M.; Snow, Robert W.
2011-01-01
Many attempts have been made to quantify Africa’s malaria burden but none has addressed how urbanization will affect disease transmission and outcome, and therefore mortality and morbidity estimates. In 2003, 39% of Africa’s 850 million people lived in urban settings; by 2030, 54% of Africans are expected to do so. We present the results of a series of entomological, parasitological and behavioural meta-analyses of studies that have investigated the effect of urbanization on malaria in Africa. We describe the effect of urbanization on both the impact of malaria transmission and the concomitant improvements in access to preventative and curative measures. Using these data, we have recalculated estimates of populations at risk of malaria and the resulting mortality. We find there were 1,068,505 malaria deaths in Africa in 2000 — a modest 6.7% reduction over previous iterations. The public-health implications of these findings and revised estimates are discussed. PMID:15608702
Quantitative ptychographic reconstruction by applying a probe constraint
NASA Astrophysics Data System (ADS)
Reinhardt, J.; Schroer, C. G.
2018-04-01
The coherent scanning technique X-ray ptychography has become a routine tool for high-resolution imaging and nanoanalysis in various fields of research such as chemistry, biology or materials science. Often the ptychographic reconstruction results are analysed in order to yield absolute quantitative values for the object transmission and illuminating probe function. In this work, we address a common ambiguity encountered in scaling the object transmission and probe intensity via the application of an additional constraint to the reconstruction algorithm. A ptychographic measurement of a model sample containing nanoparticles is used as a test data set against which to benchmark in the reconstruction results depending on the type of constraint used. Achieving quantitative absolute values for the reconstructed object transmission is essential for advanced investigation of samples that are changing over time, e.g., during in-situ experiments or in general when different data sets are compared.
Elimination of mother-to-child transmission of HIV: lessons learned from success in Thailand.
Thisyakorn, Usa
2017-05-01
In 1988, the generalised HIV/AIDS epidemic in Thailand began and in the same year the first HIV-exposed infant in Thailand was born at King Chulalongkorn Memorial Hospital, Bangkok. From the early to mid-1990s, an epidemic wave of HIV-infected women and infants occurred. Heterosexual HIV transmission, as described in the Asian Epidemic Model, was the major mode of spread in Thailand, causing an increasing number of HIV-infected pregnant women. The early and concerted multi-sectoral response of Thai society reduced the prevalence of HIV infection in pregnant women from 2% in the mid-1990s to 0.6% in 2015 and mother-to-child transmission of HIV (MTCT) from an estimated 20-40% to 1.9%. Thus, Thailand became the first Asian country to achieve the World Health Organization's (WHO) targets for the elimination of MTCT. In this narrative review, the key historic evolutions of the science and policy of prevention of mother-to-child transmission of HIV (PMTCT) in Thailand that addressed the four prongs of the recommended WHO PMTCT strategy are described, and the lessons learned are discussed.
NASA Astrophysics Data System (ADS)
Ekonomou, L.; Karampelas, P.; Vita, V.; Chatzarakis, G. E.
2011-04-01
One of the most popular methods of protecting high voltage transmission lines against lightning strikes and internal overvoltages is the use of arresters. The installation of arresters in high voltage transmission lines can prevent or even reduce the lines' failure rate. Several studies based on simulation tools have been presented in order to estimate the critical currents that exceed the arresters' rated energy stress and to specify the arresters' installation interval. In this work artificial intelligence, and more specifically a Q-learning artificial neural network (ANN) model, is addressed for evaluating the arresters' failure probability. The aims of the paper are to describe in detail the developed Q-learning ANN model and to compare the results obtained by its application in operating 150 kV Greek transmission lines with those produced using a simulation tool. The satisfactory and accurate results of the proposed ANN model can make it a valuable tool for designers of electrical power systems seeking more effective lightning protection, reducing operational costs and better continuity of service.
Papagiannis, P; Baltas, D; Granero, D; Pérez-Calatayud, J; Gimeno, J; Ballester, F; Venselaar, J L M
2008-11-01
To address the limited availability of radiation shielding data for brachytherapy as well as some disparity in existing data, Monte Carlo simulation was used to generate radiation transmission data for 60Co, 137CS, 198Au, 192Ir 169Yb, 170Tm, 131Cs, 125I, and 103pd photons through concrete, stainless steel, lead, as well as lead glass and baryte concrete. Results accounting for the oblique incidence of radiation to the barrier, spectral variation with barrier thickness, and broad beam conditions in a realistic geometry are compared to corresponding data in the literature in terms of the half value layer (HVL) and tenth value layer (TVL) indices. It is also shown that radiation shielding calculations using HVL or TVL values could overestimate or underestimate the barrier thickness required to achieve a certain reduction in radiation transmission. This questions the use of HVL or TVL indices instead of the actual transmission data. Therefore, a three-parameter model is fitted to results of this work to facilitate accurate and simple radiation shielding calculations.
Jiang, Yu; Zhang, Xiaogang; Zhang, Chao; Li, Zhixiong; Sheng, Chenxing
2017-04-01
Numerical modeling has been recognized as the dispensable tools for mechanical fault mechanism analysis. Techniques, ranging from macro to nano levels, include the finite element modeling boundary element modeling, modular dynamic modeling, nano dynamic modeling and so forth. This work firstly reviewed the progress on the fault mechanism analysis for gear transmissions from the tribological and dynamic aspects. Literature review indicates that the tribological and dynamic properties were separately investigated to explore the fault mechanism in gear transmissions. However, very limited work has been done to address the links between the tribological and dynamic properties and scarce researches have been done for coal cutting machines. For this reason, the tribo-dynamic coupled model was introduced to bridge the gap between the tribological and dynamic models in fault mechanism analysis for gear transmissions in coal cutting machines. The modular dynamic modeling and nano dynamic modeling techniques are expected to establish the links between the tribological and dynamic models. Possible future research directions using the tribo dynamic coupled model were summarized to provide potential references for researchers in the field.
Role of mechanical ventilation in the airborne transmission of infectious agents in buildings.
Luongo, J C; Fennelly, K P; Keen, J A; Zhai, Z J; Jones, B W; Miller, S L
2016-10-01
Infectious disease outbreaks and epidemics such as those due to SARS, influenza, measles, tuberculosis, and Middle East respiratory syndrome coronavirus have raised concern about the airborne transmission of pathogens in indoor environments. Significant gaps in knowledge still exist regarding the role of mechanical ventilation in airborne pathogen transmission. This review, prepared by a multidisciplinary group of researchers, focuses on summarizing the strengths and limitations of epidemiologic studies that specifically addressed the association of at least one heating, ventilating and/or air-conditioning (HVAC) system-related parameter with airborne disease transmission in buildings. The purpose of this literature review was to assess the quality and quantity of available data and to identify research needs. This review suggests that there is a need for well-designed observational and intervention studies in buildings with better HVAC system characterization and measurements of both airborne exposures and disease outcomes. Studies should also be designed so that they may be used in future quantitative meta-analyses. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Guidance on management of asymptomatic neonates born to women with active genital herpes lesions.
Kimberlin, David W; Baley, Jill
2013-02-01
Herpes simplex virus (HSV) infection of the neonate is uncommon, but genital herpes infections in adults are very common. Thus, although treating an infant with neonatal herpes is a relatively rare occurrence, managing infants potentially exposed to HSV at the time of delivery occurs more frequently. The risk of transmitting HSV to an infant during delivery is determined in part by the mother's previous immunity to HSV. Women with primary genital HSV infections who are shedding HSV at delivery are 10 to 30 times more likely to transmit the virus to their newborn infants than are women with recurrent HSV infection who are shedding virus at delivery. With the availability of commercial serological tests that reliably can distinguish type-specific HSV antibodies, it is now possible to determine the type of maternal infection and, thus, further refine management of infants delivered to women who have active genital HSV lesions. The management algorithm presented herein uses both serological and virological studies to determine the risk of HSV transmission to the neonate who is delivered to a mother with active herpetic genital lesions and tailors management accordingly. The algorithm does not address the approach to asymptomatic neonates delivered to women with a history of genital herpes but no active lesions at delivery.
Guidance on Management of Asymptomatic Neonates Born to Women With Active Genital Herpes Lesions
Kimberlin, David W.; Baley, Jill; Brady, Michael T.; Byington, Carrie L.; Davies, H. Dele; Edwards, Kathryn M.; Glode, Mary P.; Jackson, Mary Anne; Keyserling, Harry L.; Maldonado, Yvonne A.; Murray, Dennis L.; Orenstein, Walter A.; Schutze, Gordon E.; Willoughby, Rodney E.; Zaoutis, Theoklis E.; Papile, Lu-Ann; Bhutani, Vinod K.; Carlo, Waldemar A.; Cummings, James; Kumar, Praveen; Polin, Richard A.; Tan, Rosemarie C.; Wang, Kasper S.; Watterberg, Kristi L.
2013-01-01
Herpes simplex virus (HSV) infection of the neonate is uncommon, but genital herpes infections in adults are very common. Thus, although treating an infant with neonatal herpes is a relatively rare occurrence, managing infants potentially exposed to HSV at the time of delivery occurs more frequently. The risk of transmitting HSV to an infant during delivery is determined in part by the mother’s previous immunity to HSV. Women with primary genital HSV infections who are shedding HSV at delivery are 10 to 30 times more likely to transmit the virus to their newborn infants than are women with recurrent HSV infection who are shedding virus at delivery. With the availability of commercial serological tests that reliably can distinguish type-specific HSV antibodies, it is now possible to determine the type of maternal infection and, thus, further refine management of infants delivered to women who have active genital HSV lesions. The management algorithm presented herein uses both serological and virological studies to determine the risk of HSV transmission to the neonate who is delivered to a mother with active herpetic genital lesions and tailors management accordingly. The algorithm does not address the approach to asymptomatic neonates delivered to women with a history of genital herpes but no active lesions at delivery. PMID:23359576
Sanada, Akira; Tanaka, Nobuo
2012-08-01
This study deals with the feedforward active control of sound transmission through a simply supported rectangular panel using vibration actuators. The control effect largely depends on the excitation method, including the number and locations of actuators. In order to obtain a large control effect at low frequencies over a wide frequency, an active transmission control method based on single structural mode actuation is proposed. Then, with the goal of examining the feasibility of the proposed method, the (1, 3) mode is selected as the target mode and a modal actuation method in combination with six point force actuators is considered. Assuming that a single input single output feedforward control is used, sound transmission in the case minimizing the transmitted sound power is calculated for some actuation methods. Simulation results showed that the (1, 3) modal actuation is globally effective at reducing the sound transmission by more than 10 dB in the low-frequency range for both normal and oblique incidences. Finally, experimental results also showed that a large reduction could be achieved in the low-frequency range, which proves the validity and feasibility of the proposed method.
Rodriguez, Indra G; Loaiza, Jose R
2017-10-10
American trypanosomiasis, or Chagas disease, is a growing public health problem in Panama, and further forest degradation due to human population growth is expected to worsen the situation. Most people infected with the parasite Trypanosoma cruzi are silently ill, and their life expectancy is severely compromised, which contributes to further deterioration of living conditions in endemic regions. Here, we review the outcomes of nearly 100 years of ecological and epidemiological investigation about Chagas disease in Panama, in an attempt to highlight progress, identify needs, and re-orient future efforts. Rhodnius pallescens and Triatoma dimidiata are both primary vectors of T. cruzi in Panama, but R. pallescens seems more efficient in human-altered forest ecosystems due to a greater degree of association with Attalea butyracea. In contrast, T. dimidiata transmits T. cruzi efficiently under more sylvatic conditions (e.g. settlements inside old-growth or secondary forest patches), where its populations reach considerable numbers irrespective of the absence of A. butyracea. A trend of increasing forest degradation, suburbanization, and development of tourism in Panama favoring the establishment of A. butyracea and other palm tree species (Acrocomia sp.) suggests that a colonist species like R. pallescens will continue to play a more prominent role in the transmission of T. cruzi than a forest specialist like T. dimidiata. However, studies about the taxonomic status and ecology of these vectors are still needed in Panama to address their transmission potential fully. The implementation of an active surveillance system and education programs could greatly minimize the risk of Chagas disease transmission in Panama, preventing fatal infections in children from endemic areas.
McDonald, Scott A; Mohamed, Rosmawati; Dahlui, Maznah; Naning, Herlianna; Kamarulzaman, Adeeba
2014-11-07
Collecting adequate information on key epidemiological indicators is a prerequisite to informing a public health response to reduce the impact of hepatitis C virus (HCV) infection in Malaysia. Our goal was to overcome the acute data shortage typical of low/middle income countries using statistical modelling to estimate the national HCV prevalence and the distribution over transmission pathways as of the end of 2009. Multi-parameter evidence synthesis methods were applied to combine all available relevant data sources - both direct and indirect - that inform the epidemiological parameters of interest. An estimated 454,000 (95% credible interval [CrI]: 392,000 to 535,000) HCV antibody-positive individuals were living in Malaysia in 2009; this represents 2.5% (95% CrI: 2.2-3.0%) of the population aged 15-64 years. Among males of Malay ethnicity, for 77% (95% CrI: 69-85%) the route of probable transmission was active or a previous history of injecting drugs. The corresponding proportions were smaller for male Chinese and Indian/other ethnic groups (40% and 71%, respectively). The estimated prevalence in females of all ethnicities was 1% (95% CrI: 0.6 to 1.4%); 92% (95% CrI: 88 to 95%) of infections were attributable to non-drug injecting routes of transmission. The prevalent number of persons living with HCV infection in Malaysia is estimated to be very high. Low/middle income countries often lack a comprehensive evidence base; however, evidence synthesis methods can assist in filling the data gaps required for the development of effective policy to address the future public health and economic burden due to HCV.
Haynie, Aisha; Plasencia, Carlos; Fields, Kimberly; Nesbitt, Elna; Lovings-Clark, Audrey; Scott, Mary; Wiltz-Beckham, Dana; Reed, Brian; Shah, Umair A
2017-01-01
Abstract Background Harris County Public Health (HCPH) is the health department for Harris County, Texas jurisdiction. Harris County as a whole is the nation’s third most populous county, with 4.3 million residents, and a TB case rate more than double that of the USA. (7.6 cases per 100,000 pop). A total, 327 individuals were diagnosed with TB in Harris County during 2015, over two-thirds occurring in foreign-born individuals. In 2016, HCPH treated an immigrant female with active TB. Initial contact investigation (CI) yielded five household contacts (HHC). Two tested positive, but refused subsequent clinical evaluation by HCPH. Two months later, HCPH was notified of a HHC hospitalized with TB. After hospital discharge, the sick HHC moved into a motel in attempts to self-isolate, but refused evaluation of additional HHC in the home, and banned home access, precluding adequate CI. After numerous phone calls, visits to motel and home, and multiple rescheduled appointments, legal action appeared inevitable. Days later, HCPH was notified of another HHC diagnosed with active TB. Methods With alarm regarding the family’s adherence to control orders, TB staff implemented an innovative multidisciplinary team-based intervention in hopes of avoiding legal action. A site visit was paid to the motel by a local health authority, two TB staff, a county public investigator, and a refugee clinic outreach worker fluent in the family’s language. Patients were presented with letters requesting immediate cooperation to avoid court filings. Questions were answered, misinformation corrected, and education provided. Results Intermediary on-site intervention using a compassionate, firm multidisciplinary team approach resulted in 16 additional family members tested, yielding an infant with active TB (Case 4) and 8 with TB Infection (TBI). Isolation breaches were also discovered. Most importantly, TB transmission cycle was interrupted. Cultural and economic barriers hindering successful interaction with family were addressed, TB misconceptions corrected, and trusting relationship developed. Conclusion This innovative multidisciplinary intervention avoided court proceedings and curtailed the TB transmission cycle. HCPH improved its non-adherence intervention process, and modified TB control orders for infectious patients residing in congregate settings. Disclosures All authors: No reported disclosures.
Evaluation of the performance of a passive-active vibration isolation system
NASA Astrophysics Data System (ADS)
Sun, L. L.; Hansen, C. H.; Doolan, C.
2015-01-01
The behavior of a feedforward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions considered here comprise a combination of the vibration transmission energy and the sum of the squared control forces. The example system considered is a rigid body connected to a simply supported plate via two isolation mounts. The overall isolation performance is evaluated by numerical simulation. The results show that the control strategies which rely on unconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. The active system with constrained control force outputs is shown to be more effective at the resonance frequencies of the supporting plate. However, in the frequency range in which rigid body modes are present, the control strategies employed using constrained actuator outputs can only achieve 5-10 dB power transmission reduction, while at off-resonance frequencies, little or no power transmission reduction can be obtained with realistic control forces. Analysis of the wave effects in the passive mounts is also presented.
Macedo, Alexandre Casimiro de; Cunha, José Evandro; Yaochite, Juliana Navarro Ueda; Tavares, Clodis Maria; Nagao-Dias, Aparecida Tiemi
Considering that the main route of Mycobacterium leprae transmission is the upper respiratory tract, detection of salivary antibodies can be a useful tool for diagnosing early infection. The study aimed to analyze salivary anti-PGL-1 IgA and IgM antibodies in 169 children aged 4-16 years old, who lived nearby or inside the house of multibacillary or paucibacillary leprosy patients in two endemic cities in Alagoas State - Brazil. Salivary anti-PGL-1 antibodies were quantified by modified ELISA method. The frequency of contact and clinical form of the index case were significantly associated with salivary antibody levels. High frequency of IgM positivity strongly suggests active transmission of M. leprae in these communities. We suggest in the present work that salivary anti-PGL IgA and IgM are important biomarkers to be used for identifying communities with probable active transmission of M. leprae. Copyright © 2017 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.
Rangarajan, Radha; Bei, Amy K; Jethwaney, Deepa; Maldonado, Priscilla; Dorin, Dominique; Sultan, Ali A; Doerig, Christian
2005-01-01
Differentiation of malaria parasites into sexual forms (gametocytes) in the vertebrate host and their subsequent development into gametes in the mosquito vector are crucial steps in the completion of the parasite's life cycle and transmission of the disease. The molecular mechanisms that regulate the sexual cycle are poorly understood. Although several signal transduction pathways have been implicated, a clear understanding of the pathways involved has yet to emerge. Here, we show that a Plasmodium berghei homologue of Plasmodium falciparum mitogen-activated kinase-2 (Pfmap-2), a gametocyte-specific mitogen-activated protein kinase (MAPK), is required for male gamete formation. Parasites lacking Pbmap-2 are competent for gametocytogenesis, but exflagellation of male gametocytes, the process that leads to male gamete formation, is almost entirely abolished in mutant parasites. Consistent with this result, transmission of mutant parasites to mosquitoes is grossly impaired. This finding identifies a crucial role for a MAPK pathway in malaria transmission. PMID:15864297
Assessment of schistosomiasis in the Dominican Republic.
Schneider, C R; Hiatt, R A; Malek, E A; Ruiz-Tiben, E
1985-01-01
Active transmission of intestinal schistosomiasis is currently limited to the southeastern part of the Dominican Republic. A population-based stool survey in 1980 detected 4 asymptomatic individuals among 114 selected at random in 2 towns and a rural community in El Seibo Province. The distribution of the transmitting snail, Biomphalaria glabrata, considerably exceeds that of Schistosoma mansoni, extending to the National District and capital city of Santo Domingo and well into certain central valley provinces. There is evidence that transmission sites have shifted during the past three decades because of urban development, molluscicidal activities and, perhaps, introduction of competing mollusks. In spite of intermittent control activities, the combination of domestic and recreational use of streams with consequent fecal contamination, and the extended distribution of B. glabrata indicates that the potential for new transmission foci is as great today as it was 10 years ago. This potential transmission of S. mansoni is a continuing threat to public health in the Dominican Republic. PMID:3931167
Genetics Content in Introductory Biology Courses for Non-Science Majors: Theory and Practice.
ERIC Educational Resources Information Center
Hott, Adam M.; Huether, Carl A.; McInerney, Joseph D.; Christianson, Carol; Fowler, Robert; Bender, Harvey; Jenkins, John; Wysocki, Annette; Markle, Glenn; Karp, Richard
2002-01-01
Presents the recommendations of the Human Genetic Education Subcommittee of the American Society of Human Genetics (ASHG) on the development of introductory biology courses for non-science majors addressing the list of concepts including evolution, transmission, gene expression, gene regulation, and genetics and society. Used an online survey to…
Strategies for Modifying Sexual Behavior for Primary and Secondary Prevention of HIV Disease.
ERIC Educational Resources Information Center
Coates, Thomas J.
1990-01-01
Outlines models for health education and community interventions targeted at reducing human immunodeficiency virus-Type 1 transmission. Notes significant gains made with regard to sexual practices among homosexual and bisexual men in some acquired immunodeficiency syndrome epicenters. Stresses need for more programs to address other high-risk…
ERIC Educational Resources Information Center
Hanbury, Ali; Eastham, Rachael
2016-01-01
Clinical sexual health consultations with young women often focus on avoiding "risks;" namely pregnancy and sexually transmitted infection transmission. They also typically fail to explore how contraception use can impact on the capacity to enjoy sexual relationships. In contrast, this paper argues that sexual pleasure should be a…
High School Students and Online Commemoration of the Group's Cultural Trauma
ERIC Educational Resources Information Center
Lazar, Alon; Hirsch, Tal Litvak
2014-01-01
This paper addresses the interaction of three equivalent issues: education, cultural trauma and the Internet. Theory suggests that the educational system plays an important role in the transmission and maintenance of the memory of a group's defining cultural trauma. However little is empirically known of the ways education influences the attitudes…
Exploring Diverse Educational Landscapes: A Relational and Responsive Lens
ERIC Educational Resources Information Center
Ford, T.; Berryman, M.; Younis, A.; Spadoni, M.; Nevin, A.; indivi
2015-01-01
Our goal in this session is to open up new pathways for addressing the seemingly immutable educational disparities, often brought about by historical power imbalances and traditional transmission pedagogies in classrooms and schools that continue to value and perpetuate a view of knowledge and learning maintained by the dominant group. We share…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-19
.... Clustering and Effective Date i. Terra-Gen Tariff Provisions 15. Terra-Gen proposes provisions to address clustering of transmission system impact studies, consistent with the guidance provided in the January 14... on how Terra-Gen may cluster studies.\\22\\ Terra-Gen's proposed clustering provisions provide, among...
Code of Federal Regulations, 2012 CFR
2012-10-01
... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Transmission Pipeline Integrity Management § 192... internal corrosion, external corrosion, and stress corrosion cracking; (2) Static or resident threats, such... its integrity management program addressing actions it will take to respond to findings from this data...
49 CFR 192.923 - How is direct assessment used and for what threats?
Code of Federal Regulations, 2011 CFR
2011-10-01
... Transmission Pipeline Integrity Management § 192.923 How is direct assessment used and for what threats? (a... corrosion (ICDA), and stress corrosion cracking (SCCDA). (b) Primary method. An operator using direct..., appendix A3, and § 192.929 if addressing stress corrosion cracking (SCCDA). (c) Supplemental method. An...
49 CFR 192.941 - What is a low stress reassessment?
Code of Federal Regulations, 2014 CFR
2014-10-01
... Management § 192.941 What is a low stress reassessment? (a) General. An operator of a transmission line that... 49 Transportation 3 2014-10-01 2014-10-01 false What is a low stress reassessment? 192.941 Section... actions to address external corrosion on the low stress covered segment. (1) Cathodically protected pipe...
49 CFR 192.941 - What is a low stress reassessment?
Code of Federal Regulations, 2011 CFR
2011-10-01
... Management § 192.941 What is a low stress reassessment? (a) General. An operator of a transmission line that... 49 Transportation 3 2011-10-01 2011-10-01 false What is a low stress reassessment? 192.941 Section... actions to address external corrosion on the low stress covered segment. (1) Cathodically protected pipe...
49 CFR 192.923 - How is direct assessment used and for what threats?
Code of Federal Regulations, 2013 CFR
2013-10-01
... Transmission Pipeline Integrity Management § 192.923 How is direct assessment used and for what threats? (a... corrosion (ICDA), and stress corrosion cracking (SCCDA). (b) Primary method. An operator using direct..., appendix A3, and § 192.929 if addressing stress corrosion cracking (SCCDA). (c) Supplemental method. An...
Code of Federal Regulations, 2011 CFR
2011-10-01
... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Transmission Pipeline Integrity Management § 192... internal corrosion, external corrosion, and stress corrosion cracking; (2) Static or resident threats, such... its integrity management program addressing actions it will take to respond to findings from this data...
Code of Federal Regulations, 2013 CFR
2013-10-01
... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Transmission Pipeline Integrity Management § 192... internal corrosion, external corrosion, and stress corrosion cracking; (2) Static or resident threats, such... its integrity management program addressing actions it will take to respond to findings from this data...
49 CFR 192.923 - How is direct assessment used and for what threats?
Code of Federal Regulations, 2012 CFR
2012-10-01
... Transmission Pipeline Integrity Management § 192.923 How is direct assessment used and for what threats? (a... corrosion (ICDA), and stress corrosion cracking (SCCDA). (b) Primary method. An operator using direct..., appendix A3, and § 192.929 if addressing stress corrosion cracking (SCCDA). (c) Supplemental method. An...
49 CFR 192.941 - What is a low stress reassessment?
Code of Federal Regulations, 2012 CFR
2012-10-01
... Management § 192.941 What is a low stress reassessment? (a) General. An operator of a transmission line that... 49 Transportation 3 2012-10-01 2012-10-01 false What is a low stress reassessment? 192.941 Section... actions to address external corrosion on the low stress covered segment. (1) Cathodically protected pipe...
Code of Federal Regulations, 2014 CFR
2014-10-01
... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Transmission Pipeline Integrity Management § 192... internal corrosion, external corrosion, and stress corrosion cracking; (2) Static or resident threats, such... its integrity management program addressing actions it will take to respond to findings from this data...
49 CFR 192.923 - How is direct assessment used and for what threats?
Code of Federal Regulations, 2014 CFR
2014-10-01
... Transmission Pipeline Integrity Management § 192.923 How is direct assessment used and for what threats? (a... corrosion (ICDA), and stress corrosion cracking (SCCDA). (b) Primary method. An operator using direct..., appendix A3, and § 192.929 if addressing stress corrosion cracking (SCCDA). (c) Supplemental method. An...
49 CFR 192.941 - What is a low stress reassessment?
Code of Federal Regulations, 2013 CFR
2013-10-01
... Management § 192.941 What is a low stress reassessment? (a) General. An operator of a transmission line that... 49 Transportation 3 2013-10-01 2013-10-01 false What is a low stress reassessment? 192.941 Section... actions to address external corrosion on the low stress covered segment. (1) Cathodically protected pipe...
USDA-ARS?s Scientific Manuscript database
Bordetella bronchiseptica is pervasive in swine populations and plays multiple roles in respiratory disease. Most studies addressing virulence factors of B. bronchiseptica utilize isolates derived from hosts other than pigs in conjunction with rodent infection models. Based on previous in vivo mouse...
Design considerations on ultra-low-power wireless transmitters for wearable medical devices.
Manstretta, Danilo
2010-01-01
A wireless transmitter for wearable bio-sensing applications must fulfill very specialized requirements. It has been estimated that for truly wearable systems it must operate with an average power consumption of less than 140 microW. The alternatives, pitfalls, and realistic performance of robust, low power signal transmission will be addressed.
ERIC Educational Resources Information Center
CAUSE, Boulder, CO.
Six papers from the 1990 CAUSE conference's Track V, Managing Telecommunications and Networking are presented. Topics address such subjects as network funding, support services, access to networks, improvement of instruction through networks, and image transmission. Papers and their authors are as follows: "What's New in…
Statewide Conference on High Technology. Proceedings (Austin, Texas, October 7-8, 1982).
ERIC Educational Resources Information Center
Texas Advisory Council for Technical - Vocational Education, Austin.
These proceedings contain 11 papers that focus on how education must change what and how it teaches to keep up with the technological revolution. The presentations address the need for vocational education to produce students with skills in electronics and data communications (including computer-to-computer transmission); office systems and…
Common Belief and the Cultural Curriculum: An Intergenerational Study of Historical Consciousness
ERIC Educational Resources Information Center
Wineburg, Sam; Mosborg, Susan; Porat, Dan; Duncan, Ariel
2007-01-01
How is historical knowledge transmitted across generations? What is the role of schooling in that transmission? The authors address these questions by reporting on a thirty-month longitudinal study into how home, school, and larger society served as contexts for the development of historical consciousness among adolescents. Fifteen families drawn…
49 CFR 1503.429 - Filing of documents with the Enforcement Docket Clerk.
Code of Federal Regulations, 2010 CFR
2010-10-01
... INVESTIGATIVE AND ENFORCEMENT PROCEDURES Assessment of Civil Penalties by TSA § 1503.429 Filing of documents.... If this e-mail address changes, TSA will provide notice of the change by notice in the Federal Register. (3) By facsimile transmission, to 410-962-1746. If this number changes, TSA will provide notice...
19 CFR 207.93 - Protection of proprietary information during panel and committee proceedings.
Code of Federal Regulations, 2014 CFR
2014-04-01
... address by facsimile transmission, expedited courier service, expedited mail service; or by personal... or an extraordinary challenge committee, any assistant to a member, court reporters and translators... competitive decision-making, as defined in US Steel Corp. v. United States, 730 F.2d 1465 (Fed. Cir. 1984...
19 CFR 207.93 - Protection of proprietary information during panel and committee proceedings.
Code of Federal Regulations, 2013 CFR
2013-04-01
... address by facsimile transmission, expedited courier service, expedited mail service; or by personal... or an extraordinary challenge committee, any assistant to a member, court reporters and translators... competitive decision-making, as defined in US Steel Corp. v. United States, 730 F.2d 1465 (Fed. Cir. 1984...
19 CFR 207.93 - Protection of proprietary information during panel and committee proceedings.
Code of Federal Regulations, 2011 CFR
2011-04-01
... address by facsimile transmission, expedited courier service, expedited mail service; or by personal... or an extraordinary challenge committee, any assistant to a member, court reporters and translators... competitive decision-making, as defined in US Steel Corp. v. United States, 730 F.2d 1465 (Fed. Cir. 1984...
19 CFR 207.93 - Protection of proprietary information during panel and committee proceedings.
Code of Federal Regulations, 2012 CFR
2012-04-01
... address by facsimile transmission, expedited courier service, expedited mail service; or by personal... or an extraordinary challenge committee, any assistant to a member, court reporters and translators... competitive decision-making, as defined in US Steel Corp. v. United States, 730 F.2d 1465 (Fed. Cir. 1984...
Thermo-activated nano-material for use in optical devices
NASA Astrophysics Data System (ADS)
Mias, Solon; Sudor, Jan; Camon, Henri
2007-05-01
In this paper we describe the use of thermo-activated PNIPAM nano-material in optical switching devices. In other publications, the PNIPAM is used either as a carrier for crystalline colloidal array self-assemblies or as micro-particles that serve as pigment bags. In this publication we use a simpler-to-fabricate pure PNIPAM solution in a semi-dilute regime. The PNIPAM devices produced are transparent at temperatures below a critical temperature of 32°C and become diffusing above this temperature. We show that at 632nm the transmission through the devices is about 75% in the transparent state while the additional attenuation achieved in the diffusing state is of the order of 38 dB. The experimental fall and rise times obtained are large (about 300ms and 5s respectively) due to the non-optimised thermal addressing scheme. In addition, spectral measurements taken in the infrared spectrum (700-1000nm) demonstrate that the cell response is flat over a large portion of the infrared spectrum in both the transparent and the diffusing states.
Impact of antiretroviral drugs on the microbiome: unknown answers to important questions
Pinto-Cardoso, Sandra; Klatt, Nichole R.; Reyes-Terán, Gustavo
2018-01-01
Purpose of review Little is known on how different antiretroviral (ARV) drugs affect the gut microbiome in HIV infection; and conflicting data exists on the effect of ARV drugs on residual inflammation/immune activation and microbial translocation. Recent findings Gut microbiome involvement in the transmission and pathogenesis of HIV infection is increasingly being recognized. Various studies have shown that antiretroviral therapy (ART) is unable to restore gut health despite effective suppression of plasma HIV viremia. Indeed, the resolution of residual inflammation and gut microbial translocation is partial under ART. Very recent studies have provided new evidence that ARV combinations can differentially affect the gut microbiome, immune activation and microbial translocation. Furthermore, a recent article uncovered a link between drug metabolism and specific microbial species indicating that microbes can directly metabolically degrade ARV drugs when administered topically. Summary There are still many unanswered questions regarding ARVs and the gut microbiome. It is, therefore, critical for researchers to address the effect of distinct ARV drugs on the microbiome and vice versa: the effects of the microbiome on ARV drug metabolism, and speculate about possible therapeutic avenues. PMID:29028667
Apondi, Rose; Bunnell, Rebecca; Ekwaru, John Paul; Moore, David; Bechange, Stevens; Khana, Kenneth; King, Rachel; Campbell, James; Tappero, Jordan; Mermin, Jonathan
2011-06-19
Long-term impact of antiretroviral therapy (ART) on sexual HIV-transmission risk in Africa is unknown. We assessed sexual behavior changes and estimated HIV transmission from HIV-infected adults on ART in Uganda. Between 2003 and 2007, we enrolled and followed ART-naive HIV-infected adults in a home-based AIDS program with annual counseling and testing for cohabitating partners, participant transmission risk-reduction plans, condom distribution and prevention support for cohabitating discordant couples. We assessed participants' HIV plasma viral load and partner-specific sexual behaviors. We defined risky sex as intercourse with inconsistent/no condom use with HIV-negative or unknown serostatus partners in previous 3 months. We compared rates using Poisson regression models, estimated transmission risk using established viral load-specific transmission estimates, and documented sero-conversion rates among HIV-discordant couples. Of 928 participants, 755 (81%) had 36 months data: 94 (10%) died and 79 (9%) missing data. Sexual activity increased from 28% (baseline) to 41% [36 months (P < 0.001)]. Of sexually active participants, 22% reported risky sex at baseline, 8% at 6 months (P < 0.001), and 14% at 36 months (P = 0.018). Median viral load among those reporting risky sex was 122,500 [interquartile range (IQR) 45 100-353 000] copies/ml pre-ART at baseline and undetectable at follow-up. One sero-conversion occurred among 62 cohabitating sero-discordant partners (0.5 sero-conversions/100 person-years). At 36 months, consistent condom use was 74% with discordant partners, 55% with unknown and 46% with concordant partners. Estimated HIV transmission risk reduced 91%, from 47.3 to 4.2/1000 person-years. Despite increased sexual activity among HIV-infected Ugandans over 3 years on ART, risky sex and estimated risk of HIV transmission remained lower than baseline levels. Integrated prevention programs could reduce HIV transmission in Africa.
Vrancken, Bram; Rambaut, Andrew; Suchard, Marc A.; Drummond, Alexei; Baele, Guy; Derdelinckx, Inge; Van Wijngaerden, Eric; Vandamme, Anne-Mieke; Van Laethem, Kristel; Lemey, Philippe
2014-01-01
Transmission lies at the interface of human immunodeficiency virus type 1 (HIV-1) evolution within and among hosts and separates distinct selective pressures that impose differences in both the mode of diversification and the tempo of evolution. In the absence of comprehensive direct comparative analyses of the evolutionary processes at different biological scales, our understanding of how fast within-host HIV-1 evolutionary rates translate to lower rates at the between host level remains incomplete. Here, we address this by analyzing pol and env data from a large HIV-1 subtype C transmission chain for which both the timing and the direction is known for most transmission events. To this purpose, we develop a new transmission model in a Bayesian genealogical inference framework and demonstrate how to constrain the viral evolutionary history to be compatible with the transmission history while simultaneously inferring the within-host evolutionary and population dynamics. We show that accommodating a transmission bottleneck affords the best fit our data, but the sparse within-host HIV-1 sampling prevents accurate quantification of the concomitant loss in genetic diversity. We draw inference under the transmission model to estimate HIV-1 evolutionary rates among epidemiologically-related patients and demonstrate that they lie in between fast intra-host rates and lower rates among epidemiologically unrelated individuals infected with HIV subtype C. Using a new molecular clock approach, we quantify and find support for a lower evolutionary rate along branches that accommodate a transmission event or branches that represent the entire backbone of transmitted lineages in our transmission history. Finally, we recover the rate differences at the different biological scales for both synonymous and non-synonymous substitution rates, which is only compatible with the ‘store and retrieve’ hypothesis positing that viruses stored early in latently infected cells preferentially transmit or establish new infections upon reactivation. PMID:24699231
The transmission system as main actor in electricity market development in Romania
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petrescu, A.M.; Mihailescu, F.
1998-07-01
At the beginning of 1998, Romanian Electricity Authority (RENEL) was a fully integrated generation, transmission and distribution company, which managed all aspects of planning, design, and operation of Romania' s electricity sector. This form of vertically integrated organization has enabled to develop the high voltage transmission system in order to transfer electricity from the large power plants on indigenous coal (lignite) to the deficit electricity areas. An analysis based on specific characteristics of Romanian Transmission System allows the identification of a suitable model cost for transmission services evaluation. The transmission electricity tariff as a market tool has become a necessitymore » for the heterogeneous Romanian power systems from the repartition of the generation against the demand location point of view. The experience of the power system development planner shows that the most suitable model for the transmission electricity system cost assessment is the rated zones in order to reflect the geographical imbalance of generation and demand and the ability of the transmission system to accommodate this imbalance. Setting principles for the cost evaluation has to be sustained by the service evaluation on the grid nodes at the interface between transmission system and distribution system. This cost evaluation under the form of incentives for new producers has to be reconsidered year by year taking into account the evolution in time both production side and demand side. The incentives have to be addressed directly to the producers and must be strong enough to provide an efficient reliable operation of the whole power system. Transmission planners have to develop new approaches to deal with the uncertainties of the market; a combination of market forces and regulation seems to ensure the best way for the quality and security of the power system beside of the efficiency of all actors from the electricity market.« less
Cherry, Chauncey; Cain, Demetria; Pope, Howard
2011-01-01
Objectives. As a result of the impact of HIV among men who have sex with men (MSM), multiple strategies for reducing HIV risks have emerged from within the gay community. One common HIV risk reduction strategy limits unprotected sex partners to those who are of the same HIV status (serosorting). We tested a novel, brief, one-on-one intervention, based on informed decision-making and delivered by peer counselors, designed to address the limitations of serosorting (e.g., risk for HIV transmission). Methods. In 2009, we recruited a group of 149 at-risk men living in Atlanta, Georgia, and randomly assigned them to an intervention condition addressing serosorting or a standard-of-care control condition. Results. Men in the serosorting intervention reported fewer sexual partners (Wald χ2 = 8.79, P < .01) at the study follow-ups. Behavioral results were also consistent with changes in psychosocial variables, including condom use self-efficacy and perceptions of risk for HIV transmission. Conclusions. With the current intervention, service providers can offer risk reduction for men arguably at the highest risk for HIV infection in the United States. Addressing risks associated with serosorting in a feasible, low-cost intervention has the potential to significantly affect the HIV epidemic. PMID:21233441
Lee, Sang-Hun; Ledri, Marco; Tóth, Blanka; Marchionni, Ivan; Henstridge, Christopher M.; Dudok, Barna; Kenesei, Kata; Barna, László; Szabó, Szilárd I.; Renkecz, Tibor; Oberoi, Michelle; Watanabe, Masahiko; Limoli, Charles L.; Horvai, George; Soltesz, Ivan
2015-01-01
Persistent CB1 cannabinoid receptor activity limits neurotransmitter release at various synapses throughout the brain. However, it is not fully understood how constitutively active CB1 receptors, tonic endocannabinoid signaling, and its regulation by multiple serine hydrolases contribute to the synapse-specific calibration of neurotransmitter release probability. To address this question at perisomatic and dendritic GABAergic synapses in the mouse hippocampus, we used a combination of paired whole-cell patch-clamp recording, liquid chromatography/tandem mass spectrometry, stochastic optical reconstruction microscopy super-resolution imaging, and immunogold electron microscopy. Unexpectedly, application of the CB1 antagonist and inverse agonist AM251 [N-1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-1-piperidinyl-1H-pyrazole-3-carboxamide], but not the neutral antagonist NESS0327 [8-chloro-1-(2,4-dichlorophenyl)-N-piperidin-1-yl-5,6-dihydro-4H-benzo[2,3]cyclohepta[2,4-b]pyrazole-3-carboxamine], significantly increased synaptic transmission between CB1-positive perisomatic interneurons and CA1 pyramidal neurons. JZL184 (4-nitrophenyl 4-[bis(1,3-benzodioxol-5-yl)(hydroxy)methyl]piperidine-1-carboxylate), a selective inhibitor of monoacylglycerol lipase (MGL), the presynaptic degrading enzyme of the endocannabinoid 2-arachidonoylglycerol (2-AG), elicited a robust increase in 2-AG levels and concomitantly decreased GABAergic transmission. In contrast, inhibition of fatty acid amide hydrolase (FAAH) by PF3845 (N-pyridin-3-yl-4-[[3-[5-(trifluoromethyl)pyridin-2-yl]oxyphenyl]methyl]piperidine-1-carboxamide) elevated endocannabinoid/endovanilloid anandamide levels but did not change GABAergic synaptic activity. However, FAAH inhibitors attenuated tonic 2-AG increase and also decreased its synaptic effects. This antagonistic interaction required the activation of the transient receptor potential vanilloid receptor TRPV1, which was concentrated on postsynaptic intracellular membrane cisternae at perisomatic GABAergic symmetrical synapses. Interestingly, neither AM251, JZL184, nor PF3845 affected CB1-positive dendritic interneuron synapses. Together, these findings are consistent with the possibility that constitutively active CB1 receptors substantially influence perisomatic GABA release probability and indicate that the synaptic effects of tonic 2-AG release are tightly controlled by presynaptic MGL activity and also by postsynaptic endovanilloid signaling and FAAH activity. SIGNIFICANCE STATEMENT Tonic cannabinoid signaling plays a critical role in the regulation of synaptic transmission. However, the mechanistic details of how persistent CB1 cannabinoid receptor activity inhibits neurotransmitter release have remained elusive. Therefore, electrophysiological recordings, lipid measurements, and super-resolution imaging were combined to elucidate those signaling molecules and mechanisms that underlie tonic cannabinoid signaling. The findings indicate that constitutive CB1 activity has pivotal function in the tonic control of hippocampal GABA release. Moreover, the endocannabinoid 2-arachidonoylglycerol (2-AG) is continuously generated postsynaptically, but its synaptic effect is regulated strictly by presynaptic monoacylglycerol lipase activity. Finally, anandamide signaling antagonizes tonic 2-AG signaling via activation of postsynaptic transient receptor potential vanilloid TRPV1 receptors. This unexpected mechanistic diversity may be necessary to fine-tune GABA release probability under various physiological and pathophysiological conditions. PMID:26157003
Griffith Energy Project Final Environmental Impact Statement
DOE Office of Scientific and Technical Information (OSTI.GOV)
N /A
1999-04-02
Griffith Energy Limited Liability Corporation (Griffith) proposes to construct and operate the Griffith Energy Project (Project), a natural gas-fuel, combined cycle power plant, on private lands south of Kingman, Ariz. The Project would be a ''merchant plant'' which means that it is not owned by a utility and there is currently no long-term commitment or obligation by any utility to purchase the capacity and energy generated by the power plant. Griffith applied to interconnect its proposed power plant with the Western Area Power Administration's (Western) Pacific Northwest-Pacific Southwest Intertie and Parker-Davis transmission systems. Western, as a major transmission system owner,more » needs to provide access to its transmission system when it is requested by an eligible organization per existing policies, regulations and laws. The proposed interconnection would integrate the power generated by the Project into the regional transmission grid and would allow Griffith to supply its power to the competitive electric wholesale market. Based on the application, Western's proposed action is to enter into an interconnection and construction agreement with Griffith for the requested interconnections. The proposed action includes the power plant, water wells and transmission line, natural gas pipelines, new electrical transmission lines and a substation, upgrade of an existing transmission line, and access road to the power plant. Construction of segments of the transmission lines and a proposed natural gas pipeline also require a grant of right-of-way across Federal lands administered by the Bureau of Land Management. Public comments on the Draft EIS are addressed in the Final EIS, including addenda and modifications made as a result of the comments and/or new information.« less
Abbott, Marvin M.; DeHay, Kelli
2008-01-01
The Ada-Vamoosa aquifer of northeastern Oklahoma is a sedimentary bedrock aquifer of Pennsylvanian age that crops out over 800 square miles of the Osage Reservation. The Osage Nation needed additional information regarding the production potential of the aquifer to aid them in future development planning. To address this need, the U.S. Geological Survey, in cooperation with the Osage Nation, conducted a study of aquifer properties in the Ada-Vamoosa aquifer. This report presents the results of the aquifer tests from 20 wells in the Ada-Vamoosa aquifer and one well in a minor aquifer east of the Ada-Vamoosa outcrop on the Osage Reservation. Well information for 17 of the 21 wells in this report was obtained from the Indian Health Service. Data collected by the U.S. Geological Survey during this investigation are pumping well data from four domestic wells collected during the summer of 2006. Transmissivity values were calculated from well pumping data or were estimated from specific capacity values depending on the reliability of the data. The estimated transmissivity values are 1.1 to 4.3 times greater than the calculated transmissivity values. The calculated and estimated transmissivity values range from 5 to 1,000 feet squared per day.
NASA Astrophysics Data System (ADS)
Yuan, Yifei; Amine, Khalil; Lu, Jun; Shahbazian-Yassar, Reza
2017-08-01
An in-depth understanding of material behaviours under complex electrochemical environment is critical for the development of advanced materials for the next-generation rechargeable ion batteries. The dynamic conditions inside a working battery had not been intensively explored until the advent of various in situ characterization techniques. Real-time transmission electron microscopy of electrochemical reactions is one of the most significant breakthroughs poised to enable radical shift in our knowledge on how materials behave in the electrochemical environment. This review, therefore, summarizes the scientific discoveries enabled by in situ transmission electron microscopy, and specifically emphasizes the applicability of this technique to address the critical challenges in the rechargeable ion battery electrodes, electrolyte and their interfaces. New electrochemical systems such as lithium-oxygen, lithium-sulfur and sodium ion batteries are included, considering the rapidly increasing application of in situ transmission electron microscopy in these areas. A systematic comparison between lithium ion-based electrochemistry and sodium ion-based electrochemistry is also given in terms of their thermodynamic and kinetic differences. The effect of the electron beam on the validity of in situ observation is also covered. This review concludes by providing a renewed perspective for the future directions of in situ transmission electron microscopy in rechargeable ion batteries.
NASA Astrophysics Data System (ADS)
Aragonès, Àngels; Maxit, Laurent; Guasch, Oriol
2015-08-01
Statistical modal energy distribution analysis (SmEdA) extends classical statistical energy analysis (SEA) to the mid frequency range by establishing power balance equations between modes in different subsystems. This circumvents the SEA requirement of modal energy equipartition and enables applying SmEdA to the cases of low modal overlap, locally excited subsystems and to deal with complex heterogeneous subsystems as well. Yet, widening the range of application of SEA is done at a price with large models because the number of modes per subsystem can become considerable when the frequency increases. Therefore, it would be worthwhile to have at one's disposal tools for a quick identification and ranking of the resonant and non-resonant paths involved in modal energy transmission between subsystems. It will be shown that previously developed graph theory algorithms for transmission path analysis (TPA) in SEA can be adapted to SmEdA and prove useful for that purpose. The case of airborne transmission between two cavities separated apart by homogeneous and ribbed plates will be first addressed to illustrate the potential of the graph approach. A more complex case representing transmission between non-contiguous cavities in a shipbuilding structure will be also presented.
Real-time transmission of digital video using variable-length coding
NASA Technical Reports Server (NTRS)
Bizon, Thomas P.; Shalkhauser, Mary JO; Whyte, Wayne A., Jr.
1993-01-01
Huffman coding is a variable-length lossless compression technique where data with a high probability of occurrence is represented with short codewords, while 'not-so-likely' data is assigned longer codewords. Compression is achieved when the high-probability levels occur so frequently that their benefit outweighs any penalty paid when a less likely input occurs. One instance where Huffman coding is extremely effective occurs when data is highly predictable and differential coding can be applied (as with a digital video signal). For that reason, it is desirable to apply this compression technique to digital video transmission; however, special care must be taken in order to implement a communication protocol utilizing Huffman coding. This paper addresses several of the issues relating to the real-time transmission of Huffman-coded digital video over a constant-rate serial channel. Topics discussed include data rate conversion (from variable to a fixed rate), efficient data buffering, channel coding, recovery from communication errors, decoder synchronization, and decoder architectures. A description of the hardware developed to execute Huffman coding and serial transmission is also included. Although this paper focuses on matters relating to Huffman-coded digital video, the techniques discussed can easily be generalized for a variety of applications which require transmission of variable-length data.
Yuan, Yifei; Amine, Khalil; Lu, Jun; Shahbazian-Yassar, Reza
2017-01-01
An in-depth understanding of material behaviours under complex electrochemical environment is critical for the development of advanced materials for the next-generation rechargeable ion batteries. The dynamic conditions inside a working battery had not been intensively explored until the advent of various in situ characterization techniques. Real-time transmission electron microscopy of electrochemical reactions is one of the most significant breakthroughs poised to enable radical shift in our knowledge on how materials behave in the electrochemical environment. This review, therefore, summarizes the scientific discoveries enabled by in situ transmission electron microscopy, and specifically emphasizes the applicability of this technique to address the critical challenges in the rechargeable ion battery electrodes, electrolyte and their interfaces. New electrochemical systems such as lithium–oxygen, lithium–sulfur and sodium ion batteries are included, considering the rapidly increasing application of in situ transmission electron microscopy in these areas. A systematic comparison between lithium ion-based electrochemistry and sodium ion-based electrochemistry is also given in terms of their thermodynamic and kinetic differences. The effect of the electron beam on the validity of in situ observation is also covered. This review concludes by providing a renewed perspective for the future directions of in situ transmission electron microscopy in rechargeable ion batteries.
Television transmission at end of second extravehicular activity
NASA Technical Reports Server (NTRS)
1971-01-01
Astronaut Edgar D. Mitchell, Apollo 14 lunar module pilot, can be seen throwing a 'javelin' left handed during a television transmission near the close of the second extravehicular activity (EVA-2) at the Apollo 14 Fra Mauro landing site. Mitchell used the staff of the Solar Wind Composition experiment as the 'javelin'. Behind Mitchell is Astronaut Alan B. Shepard Jr., commander. Also visible in the picture are the erectable S-Band antenna (left foreground) and Lunar Module (left background) (20783); Shepard can be seen preparing to swing at a golf ball during television transmission at end of EVA-2 (20784).
A novel multiple-stage antimalarial agent that inhibits protein synthesis.
Baragaña, Beatriz; Hallyburton, Irene; Lee, Marcus C S; Norcross, Neil R; Grimaldi, Raffaella; Otto, Thomas D; Proto, William R; Blagborough, Andrew M; Meister, Stephan; Wirjanata, Grennady; Ruecker, Andrea; Upton, Leanna M; Abraham, Tara S; Almeida, Mariana J; Pradhan, Anupam; Porzelle, Achim; Luksch, Torsten; Martínez, María Santos; Luksch, Torsten; Bolscher, Judith M; Woodland, Andrew; Norval, Suzanne; Zuccotto, Fabio; Thomas, John; Simeons, Frederick; Stojanovski, Laste; Osuna-Cabello, Maria; Brock, Paddy M; Churcher, Tom S; Sala, Katarzyna A; Zakutansky, Sara E; Jiménez-Díaz, María Belén; Sanz, Laura Maria; Riley, Jennifer; Basak, Rajshekhar; Campbell, Michael; Avery, Vicky M; Sauerwein, Robert W; Dechering, Koen J; Noviyanti, Rintis; Campo, Brice; Frearson, Julie A; Angulo-Barturen, Iñigo; Ferrer-Bazaga, Santiago; Gamo, Francisco Javier; Wyatt, Paul G; Leroy, Didier; Siegl, Peter; Delves, Michael J; Kyle, Dennis E; Wittlin, Sergio; Marfurt, Jutta; Price, Ric N; Sinden, Robert E; Winzeler, Elizabeth A; Charman, Susan A; Bebrevska, Lidiya; Gray, David W; Campbell, Simon; Fairlamb, Alan H; Willis, Paul A; Rayner, Julian C; Fidock, David A; Read, Kevin D; Gilbert, Ian H
2015-06-18
There is an urgent need for new drugs to treat malaria, with broad therapeutic potential and novel modes of action, to widen the scope of treatment and to overcome emerging drug resistance. Here we describe the discovery of DDD107498, a compound with a potent and novel spectrum of antimalarial activity against multiple life-cycle stages of the Plasmodium parasite, with good pharmacokinetic properties and an acceptable safety profile. DDD107498 demonstrates potential to address a variety of clinical needs, including single-dose treatment, transmission blocking and chemoprotection. DDD107498 was developed from a screening programme against blood-stage malaria parasites; its molecular target has been identified as translation elongation factor 2 (eEF2), which is responsible for the GTP-dependent translocation of the ribosome along messenger RNA, and is essential for protein synthesis. This discovery of eEF2 as a viable antimalarial drug target opens up new possibilities for drug discovery.
Rocky Mountain spotted fever: a disease in need of microbiological concern.
Walker, D H
1989-01-01
Rocky Mountain spotted fever, a life-threatening tick-transmitted infection, is the most prevalent rickettsiosis in the United States. This zoonosis is firmly entrenched in the tick host, which maintains the rickettsiae in nature by transovarian transmission. Although the incidence of disease fluctuates in various regions and nationwide, the problems of a deceptively difficult clinical diagnosis and little microbiologic diagnostic effort persist. Many empiric antibiotic regimens lack antirickettsial activity. There is neither an effective vaccine nor a generally available assay that is diagnostic during the early stages of illness, when treatment is most effective. Microbiology laboratories that offer only the archaic retrospective Weil-Felix serologic tests should review the needs of their patients. Research microbiologists who tackle these challenging organisms have an array of questions to address regarding rickettsial surface composition, structure-function analysis, and pathogenic and immune mechanisms, as well as laboratory diagnosis. PMID:2504480
Use of convalescent plasma in Ebola virus infection.
Garraud, Olivier
2017-02-01
The recent Ebola virus epidemics which threatened three West African countries (Dec.2014-Apr.2016) has urged global collaborative health organizations and countries to set up measures to stop the infection and to treat patients, near half of them being at risk of death. Convalescent plasma-recovered from rescued West Africans-was considered a feasible therapeutic option. Efficacy was difficult to evaluate because of numerous unknowns (especially evolution of neutralizing antibodies), prior to the cessation of active transmission. This raises a large body of questions spanning epidemiological, virological, immunological but also ethical, sociological and anthropological aspects, alongside with public health concerns, in order to be better prepared to the next outbreak. This essay summarizes efforts made by a large number of groups worldwide, and attempts to address still unanswered questions on the benefit of specific versus non-specific plasma on altered-leaking-vascular endothelia in Ebola infection. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Goldstein, B.; Pultz, G. N.; Carlin, D. B.; Slavin, S. E.; Ettenberg, M.
1988-01-01
The characterization of 8300 A lasers was broadened, especially in the area of beam quality. Modulation rates up to 2 Gbit/sec at output powers of 20 mW were observed, waveform fidelity was fully adequate for low BER data transmission, and wavefront measurements showed that phase aberrations were less than lamda/50. Also, individually addressable arrays of up to ten contiguous diode lasers were fabricated and tested. Each laser operates at powers up to 30 mW CW in single spatial mode. Shifting the operating wavelength of the basic CSP laser from 8300 A to 8650 A was accomplished by the addition of Si to the active region. Output power has reached 100 mW single mode, with excellent far field wave front properties. Operating life is currently approx. 1000 hrs at 35 mW CW. In addition, laser reliability, for operation at both 8300 A and 8650 A, has profited significantly from several developments in the processing procedures.
Fontana, Stefano; Buttinelli, Gabriele; Fiore, Stefano; Mulaomerovic, Mirsada; Aćimović, Jela; Amato, Concetta; Delogu, Roberto; Rezza, Giovanni; Stefanelli, Paola
2017-09-01
The WHO Regional Commission for the Certification of Poliomyelitis Eradication has recently indicated Bosnia and Herzegovina (B&H) as a high risk country for transmission, following importation, of wild poliovirus (WPV) or circulating vaccine-derived poliovirus (cVDPV). We analyzed data on Acute Flaccid Paralysis (AFP) surveillance between 2007 to 2016, and the trend of polio immunization coverage in B&H. The majority of AFP cases was recorded in 2016 suggesting an enhancement of the AFP surveillance activities. However, the decline in the immunization coverage, around 74%, and the isolation of two Sabin-like poliovirus type 2 strains, one of them close to a VDPV, require a particular attention in the area. Although B&H has successfully maintained its polio-free status since 2002 several challenges need to be addressed. © 2017 Wiley Periodicals, Inc.
Fernandez-Avila, C; Trujillo, A J
2016-10-15
Ultra-High Pressure Homogenization (100-300MPa) has great potential for technological, microbiological and nutritional aspects of fluid processing. Its effect on the oxidative stability and interfacial properties of oil-in-water emulsions prepared with 4% (w/v) of soy protein isolate and soybean oil (10 and 20%, v/v) were studied and compared to emulsions treated by conventional homogenization (15MPa). Emulsions were characterized by particle size, emulsifying activity index, surface protein concentration at the interface and by transmission electron microscopy. Primary and secondary lipid oxidation products were evaluated in emulsions upon storage. Emulsions with 20% oil treated at 100 and 200MPa exhibited the most oxidative stability due to higher amount of oil and protein surface load at the interface. This manuscript addresses the improvement in oxidative stability in emulsions treated by UHPH when compared to conventional emulsions. Copyright © 2016 Elsevier Ltd. All rights reserved.
A novel multiple-stage antimalarial agent that inhibits protein synthesis
NASA Astrophysics Data System (ADS)
Baragaña, Beatriz; Hallyburton, Irene; Lee, Marcus C. S.; Norcross, Neil R.; Grimaldi, Raffaella; Otto, Thomas D.; Proto, William R.; Blagborough, Andrew M.; Meister, Stephan; Wirjanata, Grennady; Ruecker, Andrea; Upton, Leanna M.; Abraham, Tara S.; Almeida, Mariana J.; Pradhan, Anupam; Porzelle, Achim; Martínez, María Santos; Bolscher, Judith M.; Woodland, Andrew; Norval, Suzanne; Zuccotto, Fabio; Thomas, John; Simeons, Frederick; Stojanovski, Laste; Osuna-Cabello, Maria; Brock, Paddy M.; Churcher, Tom S.; Sala, Katarzyna A.; Zakutansky, Sara E.; Jiménez-Díaz, María Belén; Sanz, Laura Maria; Riley, Jennifer; Basak, Rajshekhar; Campbell, Michael; Avery, Vicky M.; Sauerwein, Robert W.; Dechering, Koen J.; Noviyanti, Rintis; Campo, Brice; Frearson, Julie A.; Angulo-Barturen, Iñigo; Ferrer-Bazaga, Santiago; Gamo, Francisco Javier; Wyatt, Paul G.; Leroy, Didier; Siegl, Peter; Delves, Michael J.; Kyle, Dennis E.; Wittlin, Sergio; Marfurt, Jutta; Price, Ric N.; Sinden, Robert E.; Winzeler, Elizabeth A.; Charman, Susan A.; Bebrevska, Lidiya; Gray, David W.; Campbell, Simon; Fairlamb, Alan H.; Willis, Paul A.; Rayner, Julian C.; Fidock, David A.; Read, Kevin D.; Gilbert, Ian H.
2015-06-01
There is an urgent need for new drugs to treat malaria, with broad therapeutic potential and novel modes of action, to widen the scope of treatment and to overcome emerging drug resistance. Here we describe the discovery of DDD107498, a compound with a potent and novel spectrum of antimalarial activity against multiple life-cycle stages of the Plasmodium parasite, with good pharmacokinetic properties and an acceptable safety profile. DDD107498 demonstrates potential to address a variety of clinical needs, including single-dose treatment, transmission blocking and chemoprotection. DDD107498 was developed from a screening programme against blood-stage malaria parasites; its molecular target has been identified as translation elongation factor 2 (eEF2), which is responsible for the GTP-dependent translocation of the ribosome along messenger RNA, and is essential for protein synthesis. This discovery of eEF2 as a viable antimalarial drug target opens up new possibilities for drug discovery.
Lithium-assisted electrochemical welding in silicon nanowire battery electrodes.
Karki, Khim; Epstein, Eric; Cho, Jeong-Hyun; Jia, Zheng; Li, Teng; Picraux, S Tom; Wang, Chunsheng; Cumings, John
2012-03-14
From in situ transmission electron microscopy (TEM) observations, we present direct evidence of lithium-assisted welding between physically contacted silicon nanowires (SiNWs) induced by electrochemical lithiation and delithiation. This electrochemical weld between two SiNWs demonstrates facile transport of lithium ions and electrons across the interface. From our in situ observations, we estimate the shear strength of the welded region after delithiation to be approximately 200 MPa, indicating that a strong bond is formed at the junction of two SiNWs. This welding phenomenon could help address the issue of capacity fade in nanostructured silicon battery electrodes, which is typically caused by fracture and detachment of active materials from the current collector. The process could provide for more robust battery performance either through self-healing of fractured components that remain in contact or through the formation of a multiconnected network architecture. © 2012 American Chemical Society
Manju, V; Dhandapani, P; Gurusamy Neelavannan, M; Maruthamuthu, S; Berchmans, S; Palaniappan, A
2015-04-01
A facile one-step approach is developed to synthesize highly stable (up to 6months) gold nanoparticles (GNPs) using Clavam, pharmaceutical form of amoxicillin which contains a mixture of amoxicillin and potassium salt of clavulanic acid, at room temperature (25-30°C). The clavam stabilized GNPs are characterized using various techniques including UV-Visible, FT-IR spectrophotometry and transmission electron microscopy (TEM). Tunable release of clavam from clavam stabilized GNPs is demonstrated using intracellular concentrations of glutathione (GSH). The process is monitored using an UV-Vis spectroscopy and the amount of clavam released in terms of amoxicillin concentration is quantitatively estimated using reverse phase high performance liquid chromatographic (RP-HPLC) technique. In vitro study reveals that the clavam released from GNPs' surface was found to show a significant enhancement in antibacterial activity against Escherichia coli and the cause of enhancement is addressed. Copyright © 2015 Elsevier B.V. All rights reserved.
Sensor-Only System Identification for Structural Health Monitoring of Advanced Aircraft
NASA Technical Reports Server (NTRS)
Kukreja, Sunil L.; Bernstein, Dennis S.
2012-01-01
Environmental conditions, cyclic loading, and aging contribute to structural wear and degradation, and thus potentially catastrophic events. The challenge of health monitoring technology is to determine incipient changes accurately and efficiently. This project addresses this challenge by developing health monitoring techniques that depend only on sensor measurements. Since actively controlled excitation is not needed, sensor-to-sensor identification (S2SID) provides an in-flight diagnostic tool that exploits ambient excitation to provide advance warning of significant changes. S2SID can subsequently be followed up by ground testing to localize and quantify structural changes. The conceptual foundation of S2SID is the notion of a pseudo-transfer function, where one sensor is viewed as the pseudo-input and another is viewed as the pseudo-output, is approach is less restrictive than transmissibility identification and operational modal analysis since no assumption is made about the locations of the sensors relative to the excitation.
Ono, Maki; Varma, Niraj
2017-05-01
Strong evidence exists for the utility of remote monitoring in cardiac implantable electronic devices for early detection of arrhythmias and evaluation of system performance. The application of remote monitoring for the management of chronic disease such as heart failure has been an active area of research. Areas covered: This review aims to cover the latest evidence of remote monitoring of implantable cardiac defibrillators in terms of heart failure prognosis. This article also updates the current technology relating to the method and discusses key factors to be addressed in order to better use the approach. PubMed and internet searches were conducted to acquire most recent data and technology information. Expert commentary: Multiparameter monitoring with automatic transmission is useful for heart failure management. Improved adherence to remote monitoring and an optimal algorithm for transmitted alerts and their management are warranted in the management of heart failure.
AC field exposure study: human exposure to 60-Hz electric fields
DOE Office of Scientific and Technical Information (OSTI.GOV)
Silva, J.M.
1985-04-01
The objective of this study was to develop a method of estimating human exposure to the 60 Hz electric fields created by transmission lines. The Activity Systems Model simulates human activities in a variety of situations where exposure to electric fields is possible. The model combines maps of electric fields, activity maps, and experimentally determined activity factors to provide histograms of time spent in electric fields of various strengths in the course of agricultural, recreational, and domestic activities. For corroboration, the study team measured actual human exposure at locations across the United States near transmission lines ranging in voltage frommore » 115 to 1200 kV. The data were collected with a specially designed vest that measures exposure. These data demonstrate the accuracy of the exposure model presented in this report and revealed that most exposure time is spent in fields of magnitudes similar to many household situations. The report provides annual exposure estimates for human activities near transmission lines and in the home and compares them with exposure data from typical laboratory animal experiments. For one exposure index, the cumulative product of time and electric field, exposure during some of the laboratory animal experiments is two to four orders of magnitude greater than cumulative exposure for a human during one year of outdoor work on a farm crossed by a transmission line.« less
Code of Federal Regulations, 2011 CFR
2011-10-01
... MHz. (3) Exceed an EIRP toward the physical horizon (not to include man-made structures) of 25.5 dBW... active transmission interval, of discrete out-of-band emissions of less than 700 Hz bandwidth from such... EIRP, measured over any two-millisecond active transmission interval, of discrete out-of-band emissions...
Code of Federal Regulations, 2010 CFR
2010-10-01
... MHz. (3) Exceed an EIRP toward the physical horizon (not to include man-made structures) of 25.5 dBW... active transmission interval, of discrete out-of-band emissions of less than 700 Hz bandwidth from such... EIRP, measured over any two-millisecond active transmission interval, of discrete out-of-band emissions...
Code of Federal Regulations, 2012 CFR
2012-10-01
... MHz. (3) Exceed an EIRP toward the physical horizon (not to include man-made structures) of 25.5 dBW... active transmission interval, of discrete out-of-band emissions of less than 700 Hz bandwidth from such... EIRP, measured over any two-millisecond active transmission interval, of discrete out-of-band emissions...
Banu, Sayera; Rahman, Md. Toufiq; Uddin, Mohammad Khaja Mafij; Khatun, Razia; Khan, Md. Siddiqur Rahman; Rahman, Md. Mojibur; Uddin, Syed Iftekhar; Ahmed, Tahmeed; Heffelfinger, James D.
2015-01-01
Background Understanding tuberculosis (TB) transmission dynamics is essential for establishing effective TB control strategies in settings where the burden and risk of transmission are high. The objectives of this study were to evaluate the effect of active screening on controlling TB transmission and also to characterize Mycobacterium tuberculosis strains for investigating transmission dynamics in a correctional setting. Methods The study was carried out in Dhaka Central Jail (DCJ), from October 2005 to February 2010. An active case finding strategy for pulmonary TB was established both at the entry point to the prison and inside the prison. Three sputum specimens were collected from all pulmonary TB suspects and subjected to smear microscopy, culture, and drug susceptibility testing as well as genotyping which included deletion analysis, spoligotyping and analysis of mycobacterial interspersed repetitive units (MIRU). Results A total of 60,585 inmates were screened during the study period. We found 466 inmates with pulmonary TB of whom 357 (77%) had positive smear microscopy results and 109 (23%) had negative smear microscopy results but had positive results on culture. The number of pulmonary TB cases declined significantly, from 49 cases during the first quarter to 8 cases in the final quarter of the study period (p=0.001). Deletion analysis identified all isolates as M. tuberculosis and further identified 229 (70%) strains as ‘modern’ and 100 (30%) strains as ‘ancestral’. Analysis of MIRU showed that 347 strains (85%) exhibited unique patterns, whereas 61 strains (15%) clustered into 22 groups. The largest cluster comprised eight strains of the Beijing M. tuberculosis type. The rate of recent transmission was estimated to be 9.6%. Conclusions Implementation of active screening for TB was associated with a decline in TB cases in DCJ. Implementation of active screening in prison settings might substantially reduce the national burden of TB in Bangladesh. PMID:25933377
Banu, Sayera; Rahman, Md Toufiq; Uddin, Mohammad Khaja Mafij; Khatun, Razia; Khan, Md Siddiqur Rahman; Rahman, Md Mojibur; Uddin, Syed Iftekhar; Ahmed, Tahmeed; Heffelfinger, James D
2015-01-01
Understanding tuberculosis (TB) transmission dynamics is essential for establishing effective TB control strategies in settings where the burden and risk of transmission are high. The objectives of this study were to evaluate the effect of active screening on controlling TB transmission and also to characterize Mycobacterium tuberculosis strains for investigating transmission dynamics in a correctional setting. The study was carried out in Dhaka Central Jail (DCJ), from October 2005 to February 2010. An active case finding strategy for pulmonary TB was established both at the entry point to the prison and inside the prison. Three sputum specimens were collected from all pulmonary TB suspects and subjected to smear microscopy, culture, and drug susceptibility testing as well as genotyping which included deletion analysis, spoligotyping and analysis of mycobacterial interspersed repetitive units (MIRU). A total of 60,585 inmates were screened during the study period. We found 466 inmates with pulmonary TB of whom 357 (77%) had positive smear microscopy results and 109 (23%) had negative smear microscopy results but had positive results on culture. The number of pulmonary TB cases declined significantly, from 49 cases during the first quarter to 8 cases in the final quarter of the study period (p=0.001). Deletion analysis identified all isolates as M. tuberculosis and further identified 229 (70%) strains as 'modern' and 100 (30%) strains as 'ancestral'. Analysis of MIRU showed that 347 strains (85%) exhibited unique patterns, whereas 61 strains (15%) clustered into 22 groups. The largest cluster comprised eight strains of the Beijing M. tuberculosis type. The rate of recent transmission was estimated to be 9.6%. Implementation of active screening for TB was associated with a decline in TB cases in DCJ. Implementation of active screening in prison settings might substantially reduce the national burden of TB in Bangladesh.
The Final Proceedings of the DOE/NASA Solar Power Satellite Program Review
NASA Technical Reports Server (NTRS)
1980-01-01
The solar power satellite (SPS) concept defined as 'placing gigantic satellites in geosynchronous orbit to capture sunlight, changing the energy into an appropriate form for transmission to Earth, and introducing the energy into the electric power grid' is evaluated in terms of costs and benefits. The concept development and evaluation program is reviewed in four general areas: systems definition; environmental; societal; and comparative assessments. Specific factors addressed include: transportation, construction in space, methods of conversion of sunlight into energy, transmission to Earth, maintenance in orbit and decommissioning of satellites; environmental, political, and economic effects; and comparison of SPS to other forms of power generation, both terrestrial and in space.
Tick microbiome: the force within
Narasimhan, Sukanya; Fikrig, Erol
2015-01-01
Ticks are obligate blood-feeders and serve as vectors of human and livestock pathogens worldwide. Defining the tick microbiome and deciphering the interactions between the tick and its symbiotic bacteria in the context of tick development and pathogen transmission, will likely reveal new insights and spawn new paradigms to control tick-borne diseases. Descriptive observations on the tick microbiome that began almost a century ago serve as forerunners to the gathering momentum to define the tick microbiome in greater detail. This review will focus on the current efforts to address the microbiomes of diverse ticks, and the evolving understanding of tick microbiomes. There is hope that these efforts will bring a holistic understanding of pathogen transmission by ticks. PMID:25936226
Continuous-variable quantum key distribution in non-Markovian channels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vasile, Ruggero; Olivares, Stefano; CNISM, Unita di Ricerca di Milano Universita, I-20133 Milano
2011-04-15
We address continuous-variable quantum key distribution (QKD) in non-Markovian lossy channels and show how the non-Markovian features may be exploited to enhance security and/or to detect the presence and the position of an eavesdropper along the transmission line. In particular, we suggest a coherent-state QKD protocol which is secure against Gaussian individual attacks based on optimal 1{yields}2 asymmetric cloning machines for arbitrarily low values of the overall transmission line. The scheme relies on specific non-Markovian properties, and cannot be implemented in ordinary Markovian channels characterized by uniform losses. Our results give a clear indication of the potential impact of non-Markovianmore » effects in QKD.« less
Basu, Sanjay; Stuckler, David; Gonsalves, Gregg; Lurie, Mark
2009-01-01
Background Miners in southern Africa experience incident rates of tuberculosis up to ten times greater than the general population. Migration to and from mines may be amplifying tuberculosis epidemics in the general population. Discussion Migration to and from mineral mines contributes to HIV risks and associated tuberculosis incidence. Health and safety conditions within mines also promote the risk of silicosis (a tuberculosis risk factor) and transmission of tuberculosis bacilli in close quarters. In the context of migration, current tuberculosis prevention and treatment strategies often fail to provide sufficient continuity of care to ensure appropriate tuberculosis detection and treatment. Reports from Lesotho and South Africa suggest that miners pose transmission risks to other household or community members as they travel home undetected or inadequately treated, particularly with drug-resistant forms of tuberculosis. Reducing risky exposures on the mines, enhancing the continuity of primary care services, and improving the enforcement of occupational health codes may mitigate the harmful association between mineral mining activities and tuberculosis incidence among affected communities. Summary Tuberculosis incidence appears to be amplified by mineral mining operations in southern Africa. A number of immediately-available measures to improve continuity of care for miners, change recruitment and compensation practices, and reduce the primary risk of infection may critically mitigate the negative association between mineral mining and tuberculosis. PMID:19785769
Conservation of biodiversity as a strategy for improving human health and well-being.
Kilpatrick, A Marm; Salkeld, Daniel J; Titcomb, Georgia; Hahn, Micah B
2017-06-05
The Earth's ecosystems have been altered by anthropogenic processes, including land use, harvesting populations, species introductions and climate change. These anthropogenic processes greatly alter plant and animal communities, thereby changing transmission of the zoonotic pathogens they carry. Biodiversity conservation may be a potential win-win strategy for maintaining ecosystem health and protecting public health, yet the causal evidence to support this strategy is limited. Evaluating conservation as a viable public health intervention requires answering four questions: (i) Is there a general and causal relationship between biodiversity and pathogen transmission, and if so, which direction is it in? (ii) Does increased pathogen diversity with increased host biodiversity result in an increase in total disease burden? (iii) Do the net benefits of biodiversity conservation to human well-being outweigh the benefits that biodiversity-degrading activities, such as agriculture and resource utilization, provide? (iv) Are biodiversity conservation interventions cost-effective when compared to other options employed in standard public health approaches? Here, we summarize current knowledge on biodiversity-zoonotic disease relationships and outline a research plan to address the gaps in our understanding for each of these four questions. Developing practical and self-sustaining biodiversity conservation interventions will require significant investment in disease ecology research to determine when and where they will be effective.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'. © 2017 The Author(s).
Lorenzo, Osvaldo; Beck-Sagué, Consuelo M; Bautista-Soriano, Claudia; Halpern, Mina; Roman-Poueriet, José; Henderson, Nora; Perez-Then, Eddy; Abreu-Perez, Rosa; Soto, Solange; Martínez, Luis; Rives-Gray, Sarah; Veras, Bienvenido; Connolly, Maureen; Callender, Greer Brittany; Nicholas, Stephen W
2012-01-01
In 1999, prevention of mother-to-child transmission (pMTCT) using antiretrovirals was introduced in the Dominican Republic (DR). Highly active antiretroviral therapy (HAART) was introduced for immunosuppressed persons in 2004 and for pMTCT in 2008. To assess progress towards MTCT elimination, data from requisitions for HIV nucleic acid amplification tests for diagnosis of HIV infection in perinatally exposed infants born in the DR from 1999 to 2011 were analyzed. The MTCT rate was 142/1,274 (11.1%) in 1999-2008 and 12/302 (4.0%) in 2009-2011 (P < .001), with a rate of 154/1,576 (9.8%) for both periods combined. This decline was associated with significant increases in the proportions of women who received prenatal HAART (from 12.3% to 67.9%) and infants who received exclusive formula feeding (from 76.3% to 86.1%) and declines in proportions of women who received no prenatal antiretrovirals (from 31.9% to 12.2%) or received only single-dose nevirapine (from 39.5% to 19.5%). In 2007, over 95% of DR pregnant women received prenatal care, HIV testing, and professionally attended delivery. However, only 58% of women in underserved sugarcane plantation communities (2007) and 76% in HIV sentinel surveillance hospitals (2003-2005) received their HIV test results. HIV-MTCT elimination is feasible but persistent lack of access to critical pMTCT measures must be addressed.
Conservation of biodiversity as a strategy for improving human health and well-being
Salkeld, Daniel J.; Hahn, Micah B.
2017-01-01
The Earth's ecosystems have been altered by anthropogenic processes, including land use, harvesting populations, species introductions and climate change. These anthropogenic processes greatly alter plant and animal communities, thereby changing transmission of the zoonotic pathogens they carry. Biodiversity conservation may be a potential win–win strategy for maintaining ecosystem health and protecting public health, yet the causal evidence to support this strategy is limited. Evaluating conservation as a viable public health intervention requires answering four questions: (i) Is there a general and causal relationship between biodiversity and pathogen transmission, and if so, which direction is it in? (ii) Does increased pathogen diversity with increased host biodiversity result in an increase in total disease burden? (iii) Do the net benefits of biodiversity conservation to human well-being outweigh the benefits that biodiversity-degrading activities, such as agriculture and resource utilization, provide? (iv) Are biodiversity conservation interventions cost-effective when compared to other options employed in standard public health approaches? Here, we summarize current knowledge on biodiversity–zoonotic disease relationships and outline a research plan to address the gaps in our understanding for each of these four questions. Developing practical and self-sustaining biodiversity conservation interventions will require significant investment in disease ecology research to determine when and where they will be effective. This article is part of the themed issue ‘Conservation, biodiversity and infectious disease: scientific evidence and policy implications’. PMID:28438920
Nittayananta, W; Weinberg, A; Malamud, D; Moyes, D; Webster-Cyriaque, J; Ghosh, S
2016-04-01
The interplay between HIV-1 and epithelial cells represents a critical aspect in mucosal HIV-1 transmission. Epithelial cells lining the oral cavity cover subepithelial tissues, which contain virus-susceptible host cells including CD4(+) T lymphocytes, monocytes/macrophages, and dendritic cells. Oral epithelia are among the sites of first exposure to both cell-free and cell-associated virus HIV-1 through breast-feeding and oral-genital contact. However, oral mucosa is considered to be naturally resistant to HIV-1 transmission. Oral epithelial cells have been shown to play a crucial role in innate host defense. Nevertheless, it is not clear to what degree these local innate immune factors contribute to HIV-1 resistance of the oral mucosa. This review paper addressed the following issues that were discussed at the 7th World Workshop on Oral Health and Disease in AIDS held in Hyderabad, India, during November 6-9, 2014: (i) What is the fate of HIV-1 after interactions with oral epithelial cells?; (ii) What are the keratinocyte and other anti-HIV effector oral factors, and how do they contribute to mucosal protection?; (iii) How can HIV-1 interactions with oral epithelium affect activation and populations of local immune cells?; (iv) How can HIV-1 interactions alter functions of oral epithelial cells? © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Oladele, Edward Adekola; Khamofu, Hadiza; Asala, Seun; Saleh, Mariya; Ralph-Opara, Uche; Nwosisi, Charles; Anyaike, Chukwuma; Gana, Catherine; Adedokun, Oluwasanmi; Dirks, Rebecca; Adebayo, Olufunsho; Oduwole, Modupe; Mandala, Justin; Torpey, Kwasi
2017-01-01
As the world is making progress towards elimination of mother-to-child transmission of HIV, poor coverage of PMTCT services in Nigeria remains a major challenge. In order to address this, scale-up was planned with activities organized into 3 phases. This paper describes the process undertaken in eight high burden Nigerian states to rapidly close PMTCT coverage gaps at facility and population levels between February 2013 and March 2014. Activities were grouped into three phases-pre-assessment phase (engagement of a wide range of stakeholders), assessment (rapid health facility assessment, a cross sectional survey using mixed methods conducted in the various states between Feb and May 2013 and impact modelling), and post-assessment (drawing up costed state operational plans to achieve eMTCT by 2015, data-driven smart scale-up). Over a period of 10 months starting June 2013, 2044 facilities were supported to begin provision of PMTCT services. This increased facility coverage from 8% to 50%. A 246% increase was also recorded in the number of pregnant women and their families who have access to HIV testing and counselling in the context of PMTCT. Similarly, access to antiretrovirals for PMTCT has witnessed a 152% increase in these eight states between October 2013 and October 2014. A data-driven and participatory approach can be used to rapidly scale-up PMTCT services at community and facility levels in this region. These results present us with hope for real progress in Nigeria. We are confident that the efforts described here will contribute significantly to eliminating new pediatric HIV infection in Nigeria.
Solar Power Satellite Microwave Transmission and Reception
NASA Technical Reports Server (NTRS)
Dietz, R. H.
1980-01-01
Numerous analytical and experimental investigations related to SPS microwave power transmission and reception are reported. Aspects discussed include system performance, phase control, power amplifiers, radiating elements, rectenna, solid state configurations, and planned program activities.
Voss, Bianca; Thienel, Renate; Reske, Martina; Kellermann, Thilo; Sheldrick, Abigail J; Halfter, Sarah; Radenbach, Katrin; Shah, Nadim J; Habel, Ute; Kircher, Tilo T J
2012-06-01
The connection between cholinergic transmission and cognitive performance has been established in behavioural studies. The specific contribution of the muscarinic receptor system on cognitive performance and brain activation, however, has not been evaluated satisfyingly. To investigate the specific contribution of the muscarinic transmission on neural correlates of working memory, we examined the effects of scopolamine, an antagonist of the muscarinic receptors, using functional magnetic resonance imaging (fMRI). Fifteen healthy male, non-smoking subjects performed a fMRI scanning session following the application of scopolamine (0.4 mg, i.v.) or saline in a placebo-controlled, repeated measure, pseudo-randomized, single-blind design. Working memory was probed using an n-back task. Compared to placebo, challenging the cholinergic transmission with scopolamine resulted in hypoactivations in parietal, occipital and cerebellar areas and hyperactivations in frontal and prefrontal areas. These alterations are interpreted as compensatory strategies used to account for downregulation due to muscarinic acetylcholine blockade in parietal and cerebral storage systems by increased activation in frontal and prefrontal areas related to working memory rehearsal. Our results further underline the importance of cholinergic transmission to working memory performance and determine the specific contribution of muscarinic transmission on cerebral activation associated with executive functioning.
Vanaerschot, Manu; Lucantoni, Leonardo; Li, Tao; Combrinck, Jill M.; Ruecker, Andrea; Kumar, T.R. Santha; Rubiano, Kelly; Ferreira, Pedro E.; Siciliano, Giulia; Gulati, Sonia; Henrich, Philipp P.; Ng, Caroline L.; Murithi, James M.; Corey, Victoria C.; Duffy, Sandra; Lieberman, Ori J.; Veiga, M. Isabel; Sinden, Robert E.; Alano, Pietro; Delves, Michael J.; Sim, Kim Lee; Winzeler, Elizabeth A.; Egan, Timothy J.; Hoffman, Stephen L.; Avery, Vicky M.; Fidock, David A.
2017-01-01
Antimalarial compounds with dual therapeutic and transmission-blocking activity are desired as high-value partners for combination therapies. Here, we report the identification and characterization of hexahydroquinolines (HHQs) that show low nanomolar potency against both pathogenic and transmissible intra-erythrocytic forms of the malaria parasite Plasmodium falciparum. This activity translates into potent transmission-blocking potential, as shown by in vitro male gamete formation assays and reduced oocyst infection and prevalence in Anopheles mosquitoes. In vivo studies illustrated the ability of lead HHQs to suppress P. berghei blood-stage parasite proliferation. Resistance selection studies, confirmed by CRISPR/Cas9-based gene editing, identified the digestive vacuole membrane-spanning transporter PfMDR1 as a determinant of parasite resistance to HHQs. Hemoglobin and heme fractionation assays suggest a mode of action that results in reduced hemozoin levels and might involve inhibition of host hemoglobin uptake into intra-erythrocytic parasites. Furthermore, parasites resistant to HHQs displayed increased susceptibility to several first-line antimalarial drugs including lumefantrine, confirming that HHQs have a different mode of action than other antimalarials drugs for which PfMDR1 is known to confer resistance. This work evokes therapeutic strategies that combine opposing selective pressures on this parasite transporter as an approach to countering the emergence and transmission of multidrug-resistant P. falciparum malaria. PMID:28808258
December the Twentieth (2012) Is Too Late: Addressing the "Science” of Doomsday
NASA Astrophysics Data System (ADS)
Manning, Jim; Fraknoi, A.; Schultz, G.
2010-01-01
The claimed end date of the Mayan "Long Count” calendar cycle on December 21, 2012 has given rise to assorted "New Age” speculations about major transformative events occurring in conjunction with the completion of this cycle. These speculations range from a global consciousness shift to some higher plane of understanding, to various apocalyptic disasters including increased solar activity, geomagnetic reversal, crustal displacement, and collision with a rogue planet. In recent years, the notion has spawned numerous books, History Channel programs, and a Sony Pictures film to air in late 2009 (accompanied by a viral marketing campaign describing various doomsday scenarios and offering a "survival lottery"). This current "meme” (that is, an idea that replicates through cultural transmission) represents a potential teachable moment for scientists and EPO professionals alike, but we shouldn't wait until the purported Eve of Destruction (or of Transcendental Bliss) to comment. The presenter will describe what the Astronomical Society of the Pacific is planning to do to address the attendant issues, to separate science from pseudoscience, to encourage critical thinking in the consideration of such claims, and to remind the public of legitimate threats to the planet about which we can make a positive difference. He will further encourage others to do the same.
Rashidi, Mahnaz; Galetto, Luciana; Bosco, Domenico; Bulgarelli, Andrea; Vallino, Marta; Veratti, Flavio; Marzachì, Cristina
2015-09-30
Phytoplasmas are bacterial plant pathogens (class Mollicutes), transmitted by phloem feeding leafhoppers, planthoppers and psyllids in a persistent/propagative manner. Transmission of phytoplasmas is under the control of behavioral, environmental and geographical factors, but molecular interactions between membrane proteins of phytoplasma and vectors may also be involved. The aim of the work was to provide experimental evidence that in vivo interaction between phytoplasma antigenic membrane protein (Amp) and vector proteins has a role in the transmission process. In doing so, we also investigated the topology of the interaction at the gut epithelium and at the salivary glands, the two barriers encountered by the phytoplasma during vector colonization. Experiments were performed on the 'Candidatus Phytoplasma asteris' chrysanthemum yellows strain (CYP), and the two leafhopper vectors Macrosteles quadripunctulatus Kirschbaum and Euscelidius variegatus Kirschbaum. To specifically address the interaction of CYP Amp at the gut epithelium barrier, insects were artificially fed with media containing either the recombinant phytoplasma protein Amp, or the antibody (A416) or both, and transmission, acquisition and inoculation efficiencies were measured. An abdominal microinjection protocol was employed to specifically address the interaction of CYP Amp at the salivary gland barrier. Phytoplasma suspension was added with Amp or A416 or both, injected into healthy E. variegatus adults and then infection and inoculation efficiencies were measured. An internalization assay was developed, consisting of dissected salivary glands from healthy E. variegatus exposed to phytoplasma suspension alone or together with A416 antibody. The organs were then either observed in confocal microscopy or subjected to DNA extraction and phytoplasma quantification by qPCR, to visualize and quantify possible differences among treatments in localization/presence/number of CYP cells. Artificial feeding and abdominal microinjection protocols were developed to address the two barriers separately. The in vivo interactions between Amp of 'Candidatus Phytoplasma asteris' Chrysanthemum yellows strain (CYP) and vector proteins were studied by evaluating their effects on phytoplasma transmission by Euscelidius variegatus and Macrosteles quadripunctulatus leafhoppers. An internalization assay was developed, consisting of dissected salivary glands from healthy E. variegatus exposed to phytoplasma suspension alone or together with anti-Amp antibody. To visualize possible differences among treatments in localization/presence of CYP cells, the organs were observed in confocal microscopy. Pre-feeding of E. variegatus and M. quadripunctulatus on anti-Amp antibody resulted in a significant decrease of acquisition efficiencies in both species. Inoculation efficiency of microinjected E. variegatus with CYP suspension and anti-Amp antibody was significantly reduced compared to that of the control with phytoplasma suspension only. The possibility that this was due to reduced infection efficiency or antibody-mediated inhibition of phytoplasma multiplication was ruled out. These results provided the first indirect proof of the role of Amp in the transmission process. Protocols were developed to assess the in vivo role of the phytoplasma native major antigenic membrane protein in two phases of the vector transmission process: movement through the midgut epithelium and colonization of the salivary glands. These methods will be useful also to characterize other phytoplasma-vector combinations. Results indicated for the first time that native CYP Amp is involved in vivo in specific crossing of the gut epithelium and salivary gland colonization during early phases of vector infection.
YOUR Blessed Health: A Faith-Based CBPR Approach to Addressing HIV/AIDS among African Americans
ERIC Educational Resources Information Center
Griffith, Derek M.; Pichon, Latrice C.; Campbell, Bettina; Allen, Julie Ober
2010-01-01
Despite substantial federal, state, and local efforts to reduce the transmission of HIV/AIDS, African Americans experience higher rates of infection than any other ethnic or racial group in the United States. It is imperative to develop culturally and ecologically sensitive interventions to meet the sexual health needs of this population.…
Guidelines for Safety in the Gastrointestinal Endoscopy Unit
Calderwood, Audrey H.; Chapman, Frank J.; Cohen, Jonathan; Cohen, Lawrence B.; Collins, James; Day, Lukejohn W.; Early, Dayna S.
2014-01-01
EXECUTIVE SUMMARY Historically, safety in the gastrointestinal (GI) endoscopy unit has focused on infection control, particularly around the reprocessing of endoscopes. Two highly publicized outbreaks where the transmission of infectious agents were related to GI endoscopy have highlighted the need to address potential gaps along the endoscopy care continuum that could impact patient safety. PMID:24485393
Issues in the Development of Undergraduate Courses on the Psychosocial Implications of AIDS.
ERIC Educational Resources Information Center
Heyman, Steven R.
This paper discusses the issues that should be addressed in an undergraduate course dealing with the psychosocial implications of AIDS (Acquired Immune Deficiency Syndrome). These issues are: (1) the medical aspects of HIV infection and transmission; (2) death and dying versus life and living; (3) homosexuality; (4) intravenous drug use; (5)…
40 CFR Table 3 to Subpart Oooo of... - Applicability of General Provisions to Subpart OOOO
Code of Federal Regulations, 2013 CFR
2013-07-01
... of Performance for Crude Oil and Natural Gas Production, Transmission and Distribution Pt. 60, Subpt... Yes. § 60.4 Address Yes. § 60.5 Determination of construction or modification Yes. § 60.6 Review of... in subpart OOOO. § 60.12 Circumvention Yes. § 60.13 Monitoring requirements Yes Continuous monitors...
40 CFR Table 3 to Subpart Oooo of... - Applicability of General Provisions to Subpart OOOO
Code of Federal Regulations, 2014 CFR
2014-07-01
... of Performance for Crude Oil and Natural Gas Production, Transmission and Distribution Pt. 60, Subpt... Yes. § 60.4 Address Yes. § 60.5 Determination of construction or modification Yes. § 60.6 Review of... in subpart OOOO. § 60.12 Circumvention Yes. § 60.13 Monitoring requirements Yes Continuous monitors...
USDA-ARS?s Scientific Manuscript database
Transmission of influenza A virus (IAV) from humans to swine occurs with relative frequency and is a critical contributor to swine IAV diversity. Subsequent to the introduction of these human seasonal lineages, there is often reassortment with endemic viruses and antigenic drift. To address whether ...
The Energy Imperative: Report Update
2008-11-01
projections for 2030.2 • Renewable power generation from solar , wind, biomass, and geothermal resources is growing rapidly, but these sources still...consistent policy approach to address cost, regulatory, and transmission infrastructure challenges. For solar photovoltaic (PV) technology, basic...research is particularly important to make the needed improvements in cost and performance. • Solar power can help meet peak load electricity demand
Park, Sehee; Lee, Ilseob; Kim, Jin Il; Bae, Joon-Yong; Yoo, Kirim; Kim, Juwon; Nam, Misun; Park, Miso; Yun, Soo-Hyeon; Cho, Woo In; Kim, Yeong-Su; Ko, Yun Young; Park, Man-Seong
2016-10-14
Avian influenza H7N9 virus has posed a concern of potential human-to-human transmission by resulting in seasonal virus-like human infection cases. To address the issue of sustained human infection with the H7N9 virus, here we investigated the effects of hemagglutinin (HA) and neuraminidase (NA) N-linked glycosylation (NLG) patterns on influenza virus transmission in a guinea pig model. Based on the NLG signatures identified in the HA and NA genetic sequences of H7N9 viruses, we generated NLG mutant viruses using either HA or NA gene of a H7N9 virus, A/Anhui/01/2013, by reverse genetics on the 2009 pandemic H1N1 virus backbone. For the H7 HA NLG mutant viruses, NLG pattern changes appeared to reduce viral transmissibility in guinea pigs. Intriguingly, however, the NLG changes in the N9 NA protein, such as a removal from residue 42 or 66 or an addition at residue 266, increased transmissibility of the mutant viruses by more than 33%, 50%, and 16%, respectively, compared with a parental N9 virus. Given the effects of HA-NA NLG changes with regard to viral transmission, we then generated the HA-NA NLG mutant viruses harboring the H7 HA of double NLG addition and the N9 NA of various NLG patterns. As seen in the HA NLG mutants above, the double NLG-added H7 HA decreased viral transmissibility. However, when the NA NLG changes occurred by a removal of residue 66 and an addition at 266 were additionally accompanied, the HA-NA NLG mutant virus recovered the transmissibility of its parental virus. These demonstrate the effects of specific HA-NA NLG changes on the H7N9 virus transmission by highlighting the importance of a HA-NA functional balance. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Spontaneous Activity Drives Local Synaptic Plasticity In Vivo.
Winnubst, Johan; Cheyne, Juliette E; Niculescu, Dragos; Lohmann, Christian
2015-07-15
Spontaneous activity fine-tunes neuronal connections in the developing brain. To explore the underlying synaptic plasticity mechanisms, we monitored naturally occurring changes in spontaneous activity at individual synapses with whole-cell patch-clamp recordings and simultaneous calcium imaging in the mouse visual cortex in vivo. Analyzing activity changes across large populations of synapses revealed a simple and efficient local plasticity rule: synapses that exhibit low synchronicity with nearby neighbors (<12 μm) become depressed in their transmission frequency. Asynchronous electrical stimulation of individual synapses in hippocampal slices showed that this is due to a decrease in synaptic transmission efficiency. Accordingly, experimentally increasing local synchronicity, by stimulating synapses in response to spontaneous activity at neighboring synapses, stabilized synaptic transmission. Finally, blockade of the high-affinity proBDNF receptor p75(NTR) prevented the depression of asynchronously stimulated synapses. Thus, spontaneous activity drives local synaptic plasticity at individual synapses in an "out-of-sync, lose-your-link" fashion through proBDNF/p75(NTR) signaling to refine neuronal connectivity. VIDEO ABSTRACT. Copyright © 2015 Elsevier Inc. All rights reserved.
Effectiveness of a passive-active vibration isolation system with actuator constraints
NASA Astrophysics Data System (ADS)
Sun, Lingling; Sun, Wei; Song, Kongjie; Hansen, Colin H.
2014-05-01
In the prediction of active vibration isolation performance, control force requirements were ignored in previous work. This may limit the realization of theoretically predicted isolation performance if control force of large magnitude cannot be supplied by actuators. The behavior of a feed-forward active isolation system subjected to actuator output constraints is investigated. Distributed parameter models are developed to analyze the system response, and to produce a transfer matrix for the design of an integrated passive-active isolation system. Cost functions comprising a combination of the vibration transmission energy and the sum of the squared control forces are proposed. The example system considered is a rigid body connected to a simply supported plate via two passive-active isolation mounts. Vertical and transverse forces as well as a rotational moment are applied at the rigid body, and resonances excited in elastic mounts and the supporting plate are analyzed. The overall isolation performance is evaluated by numerical simulation. The simulation results are then compared with those obtained using unconstrained control strategies. In addition, the effects of waves in elastic mounts are analyzed. It is shown that the control strategies which rely on unconstrained actuator outputs may give substantial power transmission reductions over a wide frequency range, but also require large control force amplitudes to control excited vibration modes of the system. Expected power transmission reductions for modified control strategies that incorporate constrained actuator outputs are considerably less than typical reductions with unconstrained actuator outputs. In the frequency range in which rigid body modes are present, the control strategies can only achieve 5-10 dB power transmission reduction, when control forces are constrained to be the same order of the magnitude as the primary vertical force. The resonances of the elastic mounts result in a notable increase of power transmission in high frequency range and cannot be attenuated by active control. The investigation provides a guideline for design and evaluation of active vibration isolation systems.
Kumar, Rajesh; Angov, Evelina; Kumar, Nirbhay
2014-04-01
Production of Pfs25, a Plasmodium falciparum transmission-blocking vaccine target antigen, in functional conformation with the potential to elicit effective immunogenicity still remains a major challenge. In the current study, codon-harmonized recombinant Pfs25 (CHrPfs25) was expressed in Escherichia coli, and purified protein after simple oxidative refolding steps retained reduction-sensitive conformational epitopes of transmission-blocking monoclonal antibodies. CHrPfs25 formulated in several adjuvants elicited strong immunogenicity in preclinical studies in mice. Antibodies elicited after immunization recognized native Pfs25 on the surface of live gametes of P. falciparum and demonstrated complete malaria transmission-blocking activity. The transmission-blocking efficacy was 100% even after a 1:128 dilution of sera from immunized mice in the complete Freund's adjuvant and Montanide ISA51 groups and after a 1:16 dilution of sera from mice in the alum group. The blocking was mediated by antibodies; purified IgG at concentrations as low as 31.25 μg/ml exhibited 100% transmission blocking in membrane feeding assays employing two different species of mosquitoes, Anopheles gambiae and Anopheles stephensi. This study provides the first evidence for successful expression of biologically functional rPfs25 in E. coli. The extremely potent malaria transmission-blocking activity of antibodies elicited by immunization with purified protein provides strong support for further evaluation of E. coli-derived CHrPfs25 as a malaria transmission-blocking vaccine in human clinical trials.
Gazit, Neta; Vertkin, Irena; Shapira, Ilana; Helm, Martin; Slomowitz, Edden; Sheiba, Maayan; Mor, Yael; Rizzoli, Silvio; Slutsky, Inna
2016-01-01
Summary The insulin-like growth factor-1 receptor (IGF-1R) signaling is a key regulator of lifespan, growth, and development. While reduced IGF-1R signaling delays aging and Alzheimer’s disease progression, whether and how it regulates information processing at central synapses remains elusive. Here, we show that presynaptic IGF-1Rs are basally active, regulating synaptic vesicle release and short-term plasticity in excitatory hippocampal neurons. Acute IGF-1R blockade or transient knockdown suppresses spike-evoked synaptic transmission and presynaptic cytosolic Ca2+ transients, while promoting spontaneous transmission and resting Ca2+ level. This dual effect on transmitter release is mediated by mitochondria that attenuate Ca2+ buffering in the absence of spikes and decrease ATP production during spiking activity. We conclude that the mitochondria, activated by IGF-1R signaling, constitute a critical regulator of information processing in hippocampal neurons by maintaining evoked-to-spontaneous transmission ratio, while constraining synaptic facilitation at high frequencies. Excessive IGF-1R tone may contribute to hippocampal hyperactivity associated with Alzheimer’s disease. Video Abstract PMID:26804996
Li, Yuanyuan; Leneghan, Darren B; Miura, Kazutoyo; Nikolaeva, Daria; Brian, Iona J; Dicks, Matthew D J; Fyfe, Alex J; Zakutansky, Sarah E; de Cassan, Simone; Long, Carole A; Draper, Simon J; Hill, Adrian V S; Hill, Fergal; Biswas, Sumi
2016-01-08
Transmission-blocking vaccines (TBV) target the sexual-stages of the malaria parasite in the mosquito midgut and are widely considered to be an essential tool for malaria elimination. High-titer functional antibodies are required against target antigens to achieve effective transmission-blocking activity. We have fused Pfs25, the leading malaria TBV candidate antigen to IMX313, a molecular adjuvant and expressed it both in ChAd63 and MVA viral vectors and as a secreted protein-nanoparticle. Pfs25-IMX313 expressed from viral vectors or as a protein-nanoparticle is significantly more immunogenic and gives significantly better transmission-reducing activity than monomeric Pfs25. In addition, we demonstrate that the Pfs25-IMX313 protein-nanoparticle leads to a qualitatively improved antibody response in comparison to soluble Pfs25, as well as to significantly higher germinal centre (GC) responses. These results demonstrate that antigen multimerization using IMX313 is a very promising strategy to enhance antibody responses against Pfs25, and that Pfs25-IMX313 is a highly promising TBV candidate vaccine.
Rothschild, Ryan Mark
2010-01-01
The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain-computer interfaces (BCIs), bidirectional interfaces, and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability, and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography and near-infrared spectroscopy. Then the problem of gliosis and solutions for (semi-) permanent implant biocompatibility such as innovative implant coatings, materials, and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques.
Rothschild, Ryan Mark
2010-01-01
The main focus of this review is to provide a holistic amalgamated overview of the most recent human in vivo techniques for implementing brain–computer interfaces (BCIs), bidirectional interfaces, and neuroprosthetics. Neuroengineering is providing new methods for tackling current difficulties; however neuroprosthetics have been studied for decades. Recent progresses are permitting the design of better systems with higher accuracies, repeatability, and system robustness. Bidirectional interfaces integrate recording and the relaying of information from and to the brain for the development of BCIs. The concepts of non-invasive and invasive recording of brain activity are introduced. This includes classical and innovative techniques like electroencephalography and near-infrared spectroscopy. Then the problem of gliosis and solutions for (semi-) permanent implant biocompatibility such as innovative implant coatings, materials, and shapes are discussed. Implant power and the transmission of their data through implanted pulse generators and wireless telemetry are taken into account. How sensation can be relayed back to the brain to increase integration of the neuroengineered systems with the body by methods such as micro-stimulation and transcranial magnetic stimulation are then addressed. The neuroprosthetic section discusses some of the various types and how they operate. Visual prosthetics are discussed and the three types, dependant on implant location, are examined. Auditory prosthetics, being cochlear or cortical, are then addressed. Replacement hand and limb prosthetics are then considered. These are followed by sections concentrating on the control of wheelchairs, computers and robotics directly from brain activity as recorded by non-invasive and invasive techniques. PMID:21060801
Tang, Rendong; Dai, Jiapei
2014-01-01
The processing of neural information in neural circuits plays key roles in neural functions. Biophotons, also called ultra-weak photon emissions (UPE), may play potential roles in neural signal transmission, contributing to the understanding of the high functions of nervous system such as vision, learning and memory, cognition and consciousness. However, the experimental analysis of biophotonic activities (emissions) in neural circuits has been hampered due to technical limitations. Here by developing and optimizing an in vitro biophoton imaging method, we characterize the spatiotemporal biophotonic activities and transmission in mouse brain slices. We show that the long-lasting application of glutamate to coronal brain slices produces a gradual and significant increase of biophotonic activities and achieves the maximal effect within approximately 90 min, which then lasts for a relatively long time (>200 min). The initiation and/or maintenance of biophotonic activities by glutamate can be significantly blocked by oxygen and glucose deprivation, together with the application of a cytochrome c oxidase inhibitor (sodium azide), but only partly by an action potential inhibitor (TTX), an anesthetic (procaine), or the removal of intracellular and extracellular Ca2+. We also show that the detected biophotonic activities in the corpus callosum and thalamus in sagittal brain slices mostly originate from axons or axonal terminals of cortical projection neurons, and that the hyperphosphorylation of microtubule-associated protein tau leads to a significant decrease of biophotonic activities in these two areas. Furthermore, the application of glutamate in the hippocampal dentate gyrus results in increased biophotonic activities in its intrahippocampal projection areas. These results suggest that the glutamate-induced biophotonic activities reflect biophotonic transmission along the axons and in neural circuits, which may be a new mechanism for the processing of neural information. PMID:24454909
Tang, Rendong; Dai, Jiapei
2014-01-01
The processing of neural information in neural circuits plays key roles in neural functions. Biophotons, also called ultra-weak photon emissions (UPE), may play potential roles in neural signal transmission, contributing to the understanding of the high functions of nervous system such as vision, learning and memory, cognition and consciousness. However, the experimental analysis of biophotonic activities (emissions) in neural circuits has been hampered due to technical limitations. Here by developing and optimizing an in vitro biophoton imaging method, we characterize the spatiotemporal biophotonic activities and transmission in mouse brain slices. We show that the long-lasting application of glutamate to coronal brain slices produces a gradual and significant increase of biophotonic activities and achieves the maximal effect within approximately 90 min, which then lasts for a relatively long time (>200 min). The initiation and/or maintenance of biophotonic activities by glutamate can be significantly blocked by oxygen and glucose deprivation, together with the application of a cytochrome c oxidase inhibitor (sodium azide), but only partly by an action potential inhibitor (TTX), an anesthetic (procaine), or the removal of intracellular and extracellular Ca(2+). We also show that the detected biophotonic activities in the corpus callosum and thalamus in sagittal brain slices mostly originate from axons or axonal terminals of cortical projection neurons, and that the hyperphosphorylation of microtubule-associated protein tau leads to a significant decrease of biophotonic activities in these two areas. Furthermore, the application of glutamate in the hippocampal dentate gyrus results in increased biophotonic activities in its intrahippocampal projection areas. These results suggest that the glutamate-induced biophotonic activities reflect biophotonic transmission along the axons and in neural circuits, which may be a new mechanism for the processing of neural information.
Mechanisms and targets of deep brain stimulation in movement disorders.
Johnson, Matthew D; Miocinovic, Svjetlana; McIntyre, Cameron C; Vitek, Jerrold L
2008-04-01
Chronic electrical stimulation of the brain, known as deep brain stimulation (DBS), has become a preferred surgical treatment for medication-refractory movement disorders. Despite its remarkable clinical success, the therapeutic mechanisms of DBS are still not completely understood, limiting opportunities to improve treatment efficacy and simplify selection of stimulation parameters. This review addresses three questions essential to understanding the mechanisms of DBS. 1) How does DBS affect neuronal tissue in the vicinity of the active electrode or electrodes? 2) How do these changes translate into therapeutic benefit on motor symptoms? 3) How do these effects depend on the particular site of stimulation? Early hypotheses proposed that stimulation inhibited neuronal activity at the site of stimulation, mimicking the outcome of ablative surgeries. Recent studies have challenged that view, suggesting that although somatic activity near the DBS electrode may exhibit substantial inhibition or complex modulation patterns, the output from the stimulated nucleus follows the DBS pulse train by direct axonal excitation. The intrinsic activity is thus replaced by high-frequency activity that is time-locked to the stimulus and more regular in pattern. These changes in firing pattern are thought to prevent transmission of pathologic bursting and oscillatory activity, resulting in the reduction of disease symptoms through compensatory processing of sensorimotor information. Although promising, this theory does not entirely explain why DBS improves motor symptoms at different latencies. Understanding these processes on a physiological level will be critically important if we are to reach the full potential of this powerful tool.
NASA Astrophysics Data System (ADS)
Birrell, Paul J.; Zhang, Xu-Sheng; Pebody, Richard G.; Gay, Nigel J.; de Angelis, Daniela
2016-07-01
Understanding how the geographic distribution of and movements within a population influence the spatial spread of infections is crucial for the design of interventions to curb transmission. Existing knowledge is typically based on results from simulation studies whereas analyses of real data remain sparse. The main difficulty in quantifying the spatial pattern of disease spread is the paucity of available data together with the challenge of incorporating optimally the limited information into models of disease transmission. To address this challenge the role of routine migration on the spatial pattern of infection during the epidemic of 2009 pandemic influenza in England is investigated here through two modelling approaches: parallel-region models, where epidemics in different regions are assumed to occur in isolation with shared characteristics; and meta-region models where inter-region transmission is expressed as a function of the commuter flux between regions. Results highlight that the significantly less computationally demanding parallel-region approach is sufficiently flexible to capture the underlying dynamics. This suggests that inter-region movement is either inaccurately characterized by the available commuting data or insignificant once its initial impact on transmission has subsided.
[Overview of researches for Helicobacter pylori in oral cavity and stomach].
Yang, Kaiyu; Li, Yuqing; Zhou, Xuedong
2014-06-01
Helicobacter pylori (H. pylori) is one of the most common pathogens in human and it is closely related to gastrointestinal diseases. It is essential for us to understand the transmission process of H. pylori to prevent its spreading. The oral cavity has been proposed as a reservoir for gastric H. pylori, which has been detected by culture and polymerase chain reaction (PCR) in both dental plaque and saliva. Some researchers have proposed H. pylori in oral cavity may play an important role in its transmission and reinfection. Oral-oral or fecal-oral transmission are thought to be the most possible transmit way. This review will discuss the evidence for the role of the oral cavity in the transmission of H. pylori, the difficulties encountered in addressing this topic and possible directions for future research. Oral H. pylori may also play a role in the diagnosis and prevention of deceases related to H. pylori such as gastritis, gastric ulcer and gastric carcinoma. The recent progresses in this area are also reviewed. Moreover, we also discussed the relationship between oral H. pylori and oral deceases like periodontal disease and oral ulcer.
Lin, Yun; Wang, Chao; Wang, Jiaxing; Dou, Zheng
2016-10-12
Cognitive radio sensor networks are one of the kinds of application where cognitive techniques can be adopted and have many potential applications, challenges and future research trends. According to the research surveys, dynamic spectrum access is an important and necessary technology for future cognitive sensor networks. Traditional methods of dynamic spectrum access are based on spectrum holes and they have some drawbacks, such as low accessibility and high interruptibility, which negatively affect the transmission performance of the sensor networks. To address this problem, in this paper a new initialization mechanism is proposed to establish a communication link and set up a sensor network without adopting spectrum holes to convey control information. Specifically, firstly a transmission channel model for analyzing the maximum accessible capacity for three different polices in a fading environment is discussed. Secondly, a hybrid spectrum access algorithm based on a reinforcement learning model is proposed for the power allocation problem of both the transmission channel and the control channel. Finally, extensive simulations have been conducted and simulation results show that this new algorithm provides a significant improvement in terms of the tradeoff between the control channel reliability and the efficiency of the transmission channel.
Wallace, John R; Mangas, Kirstie M; Porter, Jessica L; Marcsisin, Renee; Pidot, Sacha J; Howden, Brian; Omansen, Till F; Zeng, Weiguang; Axford, Jason K; Johnson, Paul D R; Stinear, Timothy P
2017-04-01
Addressing the transmission enigma of the neglected disease Buruli ulcer (BU) is a World Health Organization priority. In Australia, we have observed an association between mosquitoes harboring the causative agent, Mycobacterium ulcerans, and BU. Here we tested a contaminated skin model of BU transmission by dipping the tails from healthy mice in cultures of the causative agent, Mycobacterium ulcerans. Tails were exposed to mosquito (Aedes notoscriptus and Aedes aegypti) blood feeding or punctured with sterile needles. Two of 12 of mice with M. ulcerans contaminated tails exposed to feeding A. notoscriptus mosquitoes developed BU. There were no mice exposed to A. aegypti that developed BU. Eighty-eight percent of mice (21/24) subjected to contaminated tail needle puncture developed BU. Mouse tails coated only in bacteria did not develop disease. A median incubation time of 12 weeks, consistent with data from human infections, was noted. We then specifically tested the M. ulcerans infectious dose-50 (ID50) in this contaminated skin surface infection model with needle puncture and observed an ID50 of 2.6 colony-forming units. We have uncovered a biologically plausible mechanical transmission mode of BU via natural or anthropogenic skin punctures.
Brooke, M de L
2010-12-01
There is limited information about the natural history of the transmission of feather lice (Phthiraptera) from parent birds to their young. This article therefore examines the transmission of 4 species of feather lice from parent blackbirds to their nestlings in an English population, and addresses questions formulated from the perspective of the lice. The lice that disperse onto the several young in the nest were mostly found on the larger chicks, those with higher survival prospects. The lice dispersing to chicks were overwhelmingly nymphs, which cannot be sexed morphologically, and so the prediction that the adult lice dispersing would be disproportionately female, potential founders of a new population, was only supported for the most numerous species, Brueelia merulensis. There was no evidence that louse dispersal to chicks was density dependent and more likely when the parents were more heavily infested. Finally, I predicted that lice might aggregate on female blackbirds, which undertake more brooding, to increase their chance of transmission to nestlings. For 1 louse species, B. merulensis, prevalence, but not louse intensity, was higher on female than male blackbirds. For 2 other louse species, Philopterus turdi and Menacanthus eurysternus, no differences between male and female blackbirds were detected.
Sanchez, Andreas; Devevey, Godefroy; Bize, Pierre
2011-11-01
Previous studies addressing the importance of host gender in parasite transmission have shed light on males as the more important hosts, with the higher transmission potential of males being explained by the fact that they often harbour higher parasite loads than females. However, in some systems females are more heavily infected than males and may be responsible for driving infection under such circumstances. Using a wild population of common voles (Microtus arvalis), we showed that females were more frequently infected by the intestinal nematode Trichuris arvicolae than males (i.e. prevalence based on the presence of eggs in the faeces) and that females were shedding greater numbers of parasite eggs per gram of faeces (EPG) than males. By applying an anthelmintic treatment to either male or female voles, we demonstrated that treating females significantly reduced parasite burdens (i.e. prevalence and EPG) of both male and female hosts, while treating males only reduced parasite burden in males. These findings indicate that in this female-biased infection system females play a more important role than males in driving the dynamics of parasite transmission. Copyright © 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
When climate change couples social neglect: malaria dynamics in Panamá.
Hurtado, Lisbeth Amarilis; Cáceres, Lorenzo; Chaves, Luis Fernando; Calzada, José E
2014-04-01
A major challenge of infectious disease elimination is the need to interrupt pathogen transmission across all vulnerable populations. Ethnic minorities are among the key vulnerable groups deserving special attention in disease elimination initiatives, especially because their lifestyle might be intrinsically linked to locations with high transmission risk. There has been a renewed interest in malaria elimination, which has ignited a quest to understand factors necessary for sustainable malaria elimination, highlighting the need for diverse approaches to address epidemiological heterogeneity across malaria transmission settings. An analysis of malaria incidence among the Guna Amerindians of Panamá over the last 34 years showed that this ethnic minority was highly vulnerable to changes that were assumed to not impact malaria transmission. Epidemic outbreaks were linked with El Niño Southern Oscillations and were sensitive to political instability and policy changes that did not ensure adequate attention to the malaria control needs of the Gunas. Our results illustrate how the neglect of minorities poses a threat to the sustainable control and eventual elimination of malaria in Central America and other areas where ethnic minorities do not share the benefits of malaria control strategies intended for dominant ethnic groups.
Shoptaw, Steve; Montgomery, Brooke; Williams, Chyvette T; El-Bassel, Nabila; Aramrattana, Apinun; Metsch, Lisa; Metzger, David S; Kuo, Irene; Bastos, Francisco I; Strathdee, Steffanie A
2013-07-01
Efforts to prevent HIV transmission among substance-using populations have focused primarily among injection drug users, which have produced measurable reductions in HIV incidence and prevalence. By contrast, the majority of substances used worldwide are administered by noninjectable means, and there is a dearth of HIV prevention interventions that target noninjecting substance users. Increased surveillance of trends in substance use, especially cocaine (including crack) and methamphetamine, in addition to new and emerging substances (eg, synthetic cannabinoids, cathinones, and other amphetamine analogs) are needed to develop and scale up effective and robust interventions for populations at risk for HIV transmission via sexual behaviors related to noninjection substance use. Strategies are needed that address unique challenges to HIV prevention for substance users who are HIV infected and those who are HIV uninfected and are at high risk. We propose a research agenda that prioritizes (1) combination HIV-prevention strategies in substance users; (2) behavioral HIV prevention programs that reduce sexual transmission behaviors in nontreatment seeking individuals; (3) medical and/or behavioral treatments for substance abuse that reduce/eliminate substance-related sexual transmission behaviors; and (4) structural interventions to reduce HIV incidence.
Frolov, Vladimir; Backhaus, Scott; Chertkov, Misha
2014-10-01
In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~ 2700 nodes and ~ 3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polishmore » grid is used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements.« less
Lin, Yun; Wang, Chao; Wang, Jiaxing; Dou, Zheng
2016-01-01
Cognitive radio sensor networks are one of the kinds of application where cognitive techniques can be adopted and have many potential applications, challenges and future research trends. According to the research surveys, dynamic spectrum access is an important and necessary technology for future cognitive sensor networks. Traditional methods of dynamic spectrum access are based on spectrum holes and they have some drawbacks, such as low accessibility and high interruptibility, which negatively affect the transmission performance of the sensor networks. To address this problem, in this paper a new initialization mechanism is proposed to establish a communication link and set up a sensor network without adopting spectrum holes to convey control information. Specifically, firstly a transmission channel model for analyzing the maximum accessible capacity for three different polices in a fading environment is discussed. Secondly, a hybrid spectrum access algorithm based on a reinforcement learning model is proposed for the power allocation problem of both the transmission channel and the control channel. Finally, extensive simulations have been conducted and simulation results show that this new algorithm provides a significant improvement in terms of the tradeoff between the control channel reliability and the efficiency of the transmission channel. PMID:27754316
A research agenda for malaria eradication: vaccines.
2011-01-25
Vaccines could be a crucial component of efforts to eradicate malaria. Current attempts to develop malaria vaccines are primarily focused on Plasmodium falciparum and are directed towards reducing morbidity and mortality. Continued support for these efforts is essential, but if malaria vaccines are to be used as part of a repertoire of tools for elimination or eradication of malaria, they will need to have an impact on malaria transmission. We introduce the concept of "vaccines that interrupt malaria transmission" (VIMT), which includes not only "classical" transmission-blocking vaccines that target the sexual and mosquito stages but also pre-erythrocytic and asexual stage vaccines that have an effect on transmission. VIMT may also include vaccines that target the vector to disrupt parasite development in the mosquito. Importantly, if eradication is to be achieved, malaria vaccine development efforts will need to target other malaria parasite species, especially Plasmodium vivax, where novel therapeutic vaccines against hypnozoites or preventive vaccines with effect against multiple stages could have enormous impact. A target product profile (TPP) for VIMT is proposed and a research agenda to address current knowledge gaps and develop tools necessary for design and development of VIMT is presented.
Multivariable Time Series Prediction for the Icing Process on Overhead Power Transmission Line
Li, Peng; Zhao, Na; Zhou, Donghua; Cao, Min; Li, Jingjie; Shi, Xinling
2014-01-01
The design of monitoring and predictive alarm systems is necessary for successful overhead power transmission line icing. Given the characteristics of complexity, nonlinearity, and fitfulness in the line icing process, a model based on a multivariable time series is presented here to predict the icing load of a transmission line. In this model, the time effects of micrometeorology parameters for the icing process have been analyzed. The phase-space reconstruction theory and machine learning method were then applied to establish the prediction model, which fully utilized the history of multivariable time series data in local monitoring systems to represent the mapping relationship between icing load and micrometeorology factors. Relevant to the characteristic of fitfulness in line icing, the simulations were carried out during the same icing process or different process to test the model's prediction precision and robustness. According to the simulation results for the Tao-Luo-Xiong Transmission Line, this model demonstrates a good accuracy of prediction in different process, if the prediction length is less than two hours, and would be helpful for power grid departments when deciding to take action in advance to address potential icing disasters. PMID:25136653
NASA Astrophysics Data System (ADS)
Vijay Singh, Ran; Agilandeeswari, L.
2017-11-01
To handle the large amount of client’s data in open cloud lots of security issues need to be address. Client’s privacy should not be known to other group members without data owner’s valid permission. Sometime clients are fended to have accessing with open cloud servers due to some restrictions. To overcome the security issues and these restrictions related to storing, data sharing in an inter domain network and privacy checking, we propose a model in this paper which is based on an identity based cryptography in data transmission and intermediate entity which have client’s reference with identity that will take control handling of data transmission in an open cloud environment and an extended remote privacy checking technique which will work at admin side. On behalf of data owner’s authority this proposed model will give best options to have secure cryptography in data transmission and remote privacy checking either as private or public or instructed. The hardness of Computational Diffie-Hellman assumption algorithm for key exchange makes this proposed model more secure than existing models which are being used for public cloud environment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frolov, Vladimir; Backhaus, Scott N.; Chertkov, Michael
2014-01-14
In a companion manuscript, we developed a novel optimization method for placement, sizing, and operation of Flexible Alternating Current Transmission System (FACTS) devices to relieve transmission network congestion. Specifically, we addressed FACTS that provide Series Compensation (SC) via modification of line inductance. In this manuscript, this heuristic algorithm and its solutions are explored on a number of test cases: a 30-bus test network and a realistically-sized model of the Polish grid (~2700 nodes and ~3300 lines). The results on the 30-bus network are used to study the general properties of the solutions including non-locality and sparsity. The Polish grid ismore » used as a demonstration of the computational efficiency of the heuristics that leverages sequential linearization of power flow constraints and cutting plane methods that take advantage of the sparse nature of the SC placement solutions. Using these approaches, the algorithm is able to solve an instance of Polish grid in tens of seconds. We explore the utility of the algorithm by analyzing transmission networks congested by (a) uniform load growth, (b) multiple overloaded configurations, and (c) sequential generator retirements« less
Kobayashi, Miwako; Beer, Karlyn D; Bjork, Adam; Chatham-Stephens, Kevin; Cherry, Cara C; Arzoaquoi, Sampson; Frank, Wilmot; Kumeh, Odell; Sieka, Joseph; Yeiah, Adolphus; Painter, Julia E; Yoder, Jonathan S; Flannery, Brendan; Mahoney, Frank; Nyenswah, Tolbert G
2015-07-10
As of July 1, 2015, Guinea, Liberia, and Sierra Leone have reported a total of 27,443 confirmed, probable, and suspected Ebola virus disease (Ebola) cases and 11,220 deaths. Guinea and Sierra Leone have yet to interrupt transmission of Ebola virus. In January, 2016, Liberia successfully achieved Ebola transmission-free status, with no new Ebola cases occurring during a 42-day period; however, new Ebola cases were reported beginning June 29, 2015. Local cultural practices and beliefs have posed challenges to disease control, and therefore, targeted, timely health messages are needed to address practices and misperceptions that might hinder efforts to stop the spread of Ebola. As early as September 2014, Ebola spread to most counties in Liberia. To assess Ebola-related knowledge, attitudes, and practices (KAP) in the community, CDC epidemiologists who were deployed to the counties (field team), carried out a survey conducted by local trained interviewers. The survey was conducted in September and October 2014 in five counties in Liberia with varying cumulative incidence of Ebola cases. Survey results indicated several findings. First, basic awareness of Ebola was high across all surveyed populations (median correct responses = 16 of 17 questions on knowledge of Ebola transmission; range = 2-17). Second, knowledge and understanding of Ebola symptoms were incomplete (e.g., 61% of respondents said they would know if they had Ebola symptoms). Finally, certain fears about the disease were present: >90% of respondents indicated a fear of Ebola patients, >40% a fear of cured patients, and >50% a fear of treatment units (expressions of this last fear were greater in counties with lower Ebola incidence). This survey, which was conducted at a time when case counts were rapidly increasing in Liberia, indicated limited knowledge of Ebola symptoms and widespread fear of Ebola treatment units despite awareness of communication messages. Continued efforts are needed to address cultural practices and beliefs to interrupt Ebola transmission.
NASA Astrophysics Data System (ADS)
Kraemer, Rolf
2017-09-01
Wireless communications is one of the fastest growing technology fields, driving numerous other innovations in electronics. One challenging research area within the wireless field is to achieve much higher transmission rates. First products with up to 3 Gb/s are in the market. In the coming years we predict this speed growing quickly up to and beyond 100 Gb/s. Today it is an open question how we can realize a wireless system at this speed. If we intend to use such systems in a mobile environment, we can only afford to spend approximately 1-10 pW/b for the end-to-end communication. This includes RF-transmission and all processing and protocol steps. The SPP1655 of the DFG was set up to investigate new paradigms for achieving the 100 Gb/s wireless transmission goal. Within 11 coordinated projects researchers from all over Germany are addressing several relevant issues ranging from the antennas and RF-Frontend, baseband-processing and error correction to protocol processing. A number of limitations of current approaches have to be investigated and new algorithms must be found in order to achieve the intended goal. One of the big challenges is finding the correct balance between analog and digital signal processing to achieve an extremely high performance at very low energy consumption. Another challenge is to find a good balance between bandwidth and bandwidth efficiency to achieve the 100 Gbps goal. Finally, protocol processing will need new approaches to decouple the central processor of a computer from the high-end input/output operations. Within this editorial we will address the main challenges and briefly outline the approaches of the running projects. The rest of this special issue will be devoted to more detailed descriptions and achievements of the individual projects of SPP1655.
Chin, Stephanie; Yang, Donghe; Miles, Andrew J.; Eckford, Paul D. W.; Molinski, Steven; Wallace, B. A.; Bear, Christine E.
2017-01-01
Cystic fibrosis transmembrane conductance regulator (CFTR) is a multidomain membrane protein that functions as a phosphorylation-regulated anion channel. The interface between its two cytosolic nucleotide binding domains and coupling helices conferred by intracellular loops extending from the channel pore domains has been referred to as a transmission interface and is thought to be critical for the regulated channel activity of CFTR. Phosphorylation of the regulatory domain of CFTR by protein kinase A (PKA) is required for its channel activity. However, it was unclear if phosphorylation modifies the transmission interface. Here, we studied purified full-length CFTR protein using spectroscopic techniques to determine the consequences of PKA-mediated phosphorylation. Synchrotron radiation circular dichroism spectroscopy confirmed that purified full-length wild-type CFTR is folded and structurally responsive to phosphorylation. Intrinsic tryptophan fluorescence studies of CFTR showed that phosphorylation reduced iodide-mediated quenching, consistent with an effect of phosphorylation in burying tryptophans at the transmission interface. Importantly, the rate of phosphorylation-dependent channel activation was compromised by the introduction of disease-causing mutations in either of the two coupling helices predicted to interact with nucleotide binding domain 1 at the interface. Together, these results suggest that phosphorylation modifies the interface between the catalytic and pore domains of CFTR and that this modification facilitates CFTR channel activation. PMID:28003367
Can Simple Transmission Chains Foster Collective Intelligence in Binary-Choice Tasks?
Moussaïd, Mehdi; Seyed Yahosseini, Kyanoush
2016-01-01
In many social systems, groups of individuals can find remarkably efficient solutions to complex cognitive problems, sometimes even outperforming a single expert. The success of the group, however, crucially depends on how the judgments of the group members are aggregated to produce the collective answer. A large variety of such aggregation methods have been described in the literature, such as averaging the independent judgments, relying on the majority or setting up a group discussion. In the present work, we introduce a novel approach for aggregating judgments-the transmission chain-which has not yet been consistently evaluated in the context of collective intelligence. In a transmission chain, all group members have access to a unique collective solution and can improve it sequentially. Over repeated improvements, the collective solution that emerges reflects the judgments of every group members. We address the question of whether such a transmission chain can foster collective intelligence for binary-choice problems. In a series of numerical simulations, we explore the impact of various factors on the performance of the transmission chain, such as the group size, the model parameters, and the structure of the population. The performance of this method is compared to those of the majority rule and the confidence-weighted majority. Finally, we rely on two existing datasets of individuals performing a series of binary decisions to evaluate the expected performances of the three methods empirically. We find that the parameter space where the transmission chain has the best performance rarely appears in real datasets. We conclude that the transmission chain is best suited for other types of problems, such as those that have cumulative properties.
Brickley, Elizabeth B; Coulibaly, Mamadou; Gabriel, Erin E; Healy, Sara A; Hume, Jen C C; Sagara, Issaka; Traore, Sekou F; Doumbo, Ogobara; Duffy, Patrick E
2016-11-21
Shifting the malaria priorities from a paradigm of control and elimination to a goal of global eradication calls for renewed attention to the interruption of malaria transmission. Sustained progress toward eradication will require both improved understanding of infectious reservoirs and efficient development of novel transmission-blocking interventions, such as rapidly acting and highly efficacious therapeutics and vaccines. Here, we review the direct skin feeding assay (DSF), which has been proposed as a valuable tool for measuring the in natura transmission of malaria parasites from human hosts to mosquito vectors across heterogeneous populations. To capture the methodological breadth of this assay's use, we first systematically review and qualitatively synthesize previously published investigations using DSFs to study malaria transmission in humans. Then, using a recent Phase 1 trial in Mali of the Pfs25H-EPA/Alhydrogel® vaccine candidate (NCT01867463) designed to interrupt Plasmodium falciparum transmission as a case study, we describe the potential opportunities and current limitations of utilizing the endpoints measured by DSF in making early clinical decisions for individually randomized transmission-interrupting intervention candidates. Using simulations based on the data collected in the clinical trial, we demonstrate that the capacity of the DSF to serve as an evaluative tool is limited by the statistical power constraints of the "effective sample size" (i.e. the number of subjects that are capable of transmitting at the time of feeding). Altogether, our findings suggest DSFs have great potential utility for assessing the public health impacts of emerging antimalarial tools, but additional research is needed to address issues of scalability and to establish correlation with community-wide clinical endpoints as well as complementary in vitro measures, such as standard membrane feeding assays. Published by Elsevier Ltd.
Can Simple Transmission Chains Foster Collective Intelligence in Binary-Choice Tasks?
Moussaïd, Mehdi; Seyed Yahosseini, Kyanoush
2016-01-01
In many social systems, groups of individuals can find remarkably efficient solutions to complex cognitive problems, sometimes even outperforming a single expert. The success of the group, however, crucially depends on how the judgments of the group members are aggregated to produce the collective answer. A large variety of such aggregation methods have been described in the literature, such as averaging the independent judgments, relying on the majority or setting up a group discussion. In the present work, we introduce a novel approach for aggregating judgments—the transmission chain—which has not yet been consistently evaluated in the context of collective intelligence. In a transmission chain, all group members have access to a unique collective solution and can improve it sequentially. Over repeated improvements, the collective solution that emerges reflects the judgments of every group members. We address the question of whether such a transmission chain can foster collective intelligence for binary-choice problems. In a series of numerical simulations, we explore the impact of various factors on the performance of the transmission chain, such as the group size, the model parameters, and the structure of the population. The performance of this method is compared to those of the majority rule and the confidence-weighted majority. Finally, we rely on two existing datasets of individuals performing a series of binary decisions to evaluate the expected performances of the three methods empirically. We find that the parameter space where the transmission chain has the best performance rarely appears in real datasets. We conclude that the transmission chain is best suited for other types of problems, such as those that have cumulative properties. PMID:27880825
Advanced rotorcraft transmission program
NASA Technical Reports Server (NTRS)
Bill, Robert C.
1990-01-01
The Advanced Rotorcraft Transmission (ART) program is an Army-funded, joint Army/NASA program to develop and demonstrate lightweight, quiet, durable drivetrain systems for next generation rotorcraft. ART addresses the drivetrain requirements of two distinct next generation aircraft classes: Future Air Attack Vehicle, a 10,000 to 20,000 lb. aircraft capable of undertaking tactical support and air-to-air missions; and Advanced Cargo Aircraft, a 60,000 to 80,000 lb. aircraft capable of heavy life field support operations. Both tiltrotor and more conventional helicopter configurations are included in the ART program. Specific objectives of ART include reduction of drivetrain weight by 25 percent compared to baseline state-of-the-art drive systems configured and sized for the next generation aircraft, reduction of noise level at the transmission source by 10 dB relative to a suitably sized and configured baseline, and attainment of at least a 5000 hr mean-time-between-removal. The technical approach for achieving the ART goals includes application of the latest available component, material, and lubrication technology to advanced concept drivetrains that utilize new ideas in gear configuration, transmission layout, and airframe/drivetrain integration. To date, candidate drivetrain systems were carried to a conceptual design stage, and tradeoff studies were conducted resulting in selection of an ART transmission configuration for each of the four contractors. The final selection was based on comparative weight, noise, and reliability studies. A description of each of the selected ART designs is included. Preliminary design of each of the four selected ART transmission was completed, as have mission impact studies wherein comparisons of aircraft mission performance and life cycle costs are undertaken for the next generation aircraft with ART and with the baseline transmission.
Jennelle, Christopher S.; Henaux, Viviane; Wasserberg, Gideon; Thiagarajan, Bala; Rolley, Robert E.; Samuel, Michael D.
2014-01-01
Few studies have evaluated the rate of infection or mode of transmission for wildlife diseases, and the implications of alternative management strategies. We used hunter harvest data from 2002 to 2013 to investigate chronic wasting disease (CWD) infection rate and transmission modes, and address how alternative management approaches affect disease dynamics in a Wisconsin white-tailed deer population. Uncertainty regarding demographic impacts of CWD on cervid populations, human and domestic animal health concerns, and potential economic consequences underscore the need for strategies to control CWD distribution and prevalence. Using maximum-likelihood methods to evaluate alternative multi-state deterministic models of CWD transmission, harvest data strongly supports a frequency-dependent transmission structure with sex-specific infection rates that are two times higher in males than females. As transmissible spongiform encephalopathies are an important and difficult-to-study class of diseases with major economic and ecological implications, our work supports the hypothesis of frequency-dependent transmission in wild deer at a broad spatial scale and indicates that effective harvest management can be implemented to control CWD prevalence. Specifically, we show that harvest focused on the greater-affected sex (males) can result in stable population dynamics and control of CWD within the next 50 years, given the constraints of the model. We also provide a quantitative estimate of geographic disease spread in southern Wisconsin, validating qualitative assessments that CWD spreads relatively slowly. Given increased discovery and distribution of CWD throughout North America, insights from our study are valuable to management agencies and to the general public concerned about the impacts of CWD on white-tailed deer populations.
Jennelle, Christopher S.; Henaux, Viviane; Wasserberg, Gideon; Thiagarajan, Bala; Rolley, Robert E.; Samuel, Michael D.
2014-01-01
Few studies have evaluated the rate of infection or mode of transmission for wildlife diseases, and the implications of alternative management strategies. We used hunter harvest data from 2002 to 2013 to investigate chronic wasting disease (CWD) infection rate and transmission modes, and address how alternative management approaches affect disease dynamics in a Wisconsin white-tailed deer population. Uncertainty regarding demographic impacts of CWD on cervid populations, human and domestic animal health concerns, and potential economic consequences underscore the need for strategies to control CWD distribution and prevalence. Using maximum-likelihood methods to evaluate alternative multi-state deterministic models of CWD transmission, harvest data strongly supports a frequency-dependent transmission structure with sex-specific infection rates that are two times higher in males than females. As transmissible spongiform encephalopathies are an important and difficult-to-study class of diseases with major economic and ecological implications, our work supports the hypothesis of frequency-dependent transmission in wild deer at a broad spatial scale and indicates that effective harvest management can be implemented to control CWD prevalence. Specifically, we show that harvest focused on the greater-affected sex (males) can result in stable population dynamics and control of CWD within the next 50 years, given the constraints of the model. We also provide a quantitative estimate of geographic disease spread in southern Wisconsin, validating qualitative assessments that CWD spreads relatively slowly. Given increased discovery and distribution of CWD throughout North America, insights from our study are valuable to management agencies and to the general public concerned about the impacts of CWD on white-tailed deer populations. PMID:24658535
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Damaging BPA Transmission lines and property is a crime – and it can also be extremely dangerous. BPA’s toll-free, crime informant hotline allows you to report any illegal or suspicious activity you witness against BPA’s transmission system, property or personnel.
Slow-Mode MHD Wave Penetration into a Coronal Null Point due to the Mode Transmission
NASA Astrophysics Data System (ADS)
Afanasyev, Andrey N.; Uralov, Arkadiy M.
2016-11-01
Recent observations of magnetohydrodynamic oscillations and waves in solar active regions revealed their close link to quasi-periodic pulsations in flaring light curves. The nature of that link has not yet been understood in detail. In our analytical modelling we investigate propagation of slow magnetoacoustic waves in a solar active region, taking into account wave refraction and transmission of the slow magnetoacoustic mode into the fast one. The wave propagation is analysed in the geometrical acoustics approximation. Special attention is paid to the penetration of waves in the vicinity of a magnetic null point. The modelling has shown that the interaction of slow magnetoacoustic waves with the magnetic reconnection site is possible due to the mode transmission at the equipartition level where the sound speed is equal to the Alfvén speed. The efficiency of the transmission is also calculated.
Detection of allosteric signal transmission by information-theoretic analysis of protein dynamics
Pandini, Alessandro; Fornili, Arianna; Fraternali, Franca; Kleinjung, Jens
2012-01-01
Allostery offers a highly specific way to modulate protein function. Therefore, understanding this mechanism is of increasing interest for protein science and drug discovery. However, allosteric signal transmission is difficult to detect experimentally and to model because it is often mediated by local structural changes propagating along multiple pathways. To address this, we developed a method to identify communication pathways by an information-theoretical analysis of molecular dynamics simulations. Signal propagation was described as information exchange through a network of correlated local motions, modeled as transitions between canonical states of protein fragments. The method was used to describe allostery in two-component regulatory systems. In particular, the transmission from the allosteric site to the signaling surface of the receiver domain NtrC was shown to be mediated by a layer of hub residues. The location of hubs preferentially connected to the allosteric site was found in close agreement with key residues experimentally identified as involved in the signal transmission. The comparison with the networks of the homologues CheY and FixJ highlighted similarities in their dynamics. In particular, we showed that a preorganized network of fragment connections between the allosteric and functional sites exists already in the inactive state of all three proteins.—Pandini, A., Fornili, A., Fraternali, F., Kleinjung, J. Detection of allosteric signal transmission by information-theoretic analysis of protein dynamics. PMID:22071506
On the transmission of terahertz radiation through silicon-based structures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Persano, Anna, E-mail: anna.persano@le.imm.cnr.it; Francioso, Luca; Cola, Adriano
2014-07-28
We report on the transmission of a terahertz (THz) radiation through prototype structures based on a p-type silicon substrate. In particular, the bare substrate and progressively more complicated multilayer structures were investigated, allowing to address the effect on the transmission of different factors, such as the orientation of interdigitated contacts with respect to the polarized beam, the temperature, and the current flowing through a conductive SnO{sub 2} nanorods layer. A suitable experimental set-up was developed for the direct spectral measurement of transmission in the range of 0.75–1.1 THz at room and low temperatures. A simple Drude-Lorentz model was formulated, findingmore » a quantitative agreement with the experimental transmission spectrum of the bare substrate at room temperature. For the multilayer structures, the spectra variations observed with temperature are well accounted by the corresponding change of the mobility of holes in the silicon p-type substrate. The influence of the contact orientation is consistent with that of a polarizing metallic grating. Finally, Joule heating effects are observed in the spectra performed as a function of the current flowing through the SnO{sub 2} nanorods layer. The experimental results shown here, together with their theoretical interpretation, provide insights for the development of devices fabricated on conductive substrates aimed to absorb/modulate radiation in the THz range.« less
Intelligent Local Avoided Collision (iLAC) MAC Protocol for Very High Speed Wireless Network
NASA Astrophysics Data System (ADS)
Hieu, Dinh Chi; Masuda, Akeo; Rabarijaona, Verotiana Hanitriniala; Shimamoto, Shigeru
Future wireless communication systems aim at very high data rates. As the medium access control (MAC) protocol plays the central role in determining the overall performance of the wireless system, designing a suitable MAC protocol is critical to fully exploit the benefit of high speed transmission that the physical layer (PHY) offers. In the latest 802.11n standard [2], the problem of long overhead has been addressed adequately but the issue of excessive colliding transmissions, especially in congested situation, remains untouched. The procedure of setting the backoff value is the heart of the 802.11 distributed coordination function (DCF) to avoid collision in which each station makes its own decision on how to avoid collision in the next transmission. However, collision avoidance is a problem that can not be solved by a single station. In this paper, we introduce a new MAC protocol called Intelligent Local Avoided Collision (iLAC) that redefines individual rationality in choosing the backoff counter value to avoid a colliding transmission. The distinguishing feature of iLAC is that it fundamentally changes this decision making process from collision avoidance to collaborative collision prevention. As a result, stations can avoid colliding transmissions with much greater precision. Analytical solution confirms the validity of this proposal and simulation results show that the proposed algorithm outperforms the conventional algorithms by a large margin.
Recent developments of the in situ wet cell technology for transmission electron microscopies.
Chen, Xin; Li, Chang; Cao, Hongling
2015-03-21
In situ wet cells for transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) allow studying structures and processes in a liquid environment with high temporal and spatial resolutions, and have been attracting increasing research interests in many fields. In this review, we highlight the structural and functional developments of the wet cells for TEM and STEM. One of the key features of the wet cells is the sealing technique used to isolate the liquid sample from the TEM/STEM vacuum environments, thus the existing in situ wet cells are grouped by different sealing methods. In this study, the advantages and shortcomings of each type of in situ wet cells are discussed, the functional developments of different wet cells are presented, and the future trends of the wet cell technology are addressed. It is suggested that in the future the in situ wet cell TEM/STEM technology will have an increasing impact on frontier nanoscale research.
A Preliminary Study of Building a Transmission Overlay for Regional US Power Grid
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lei, Yin; Li, Yalong; Liu, Yilu
2015-01-01
Many European countries have taken steps toward a Supergrid in order to transmit large amount of intermittent and remote renewable energy over long distance to load centers. In the US, as the expected increase in renewable generation and electricity demand, similar problem arises. A potential solution is to upgrade the transmission system at a higher voltage by constructing a new overlay grid. This paper will first address basic requirements for such an overlay grid. Potential transmission technologies will also be discussed. A multi-terminal VSC HVDC model is developed in DSATools to implement the overlay grid and a test case onmore » a regional NPCC system will be simulated. Another test system of entire US power grid, with three different interconnections tied together using back-to-back HVDC, is also introduced in this paper. Building an overlay system on top of this test case is ongoing, and will be discussed in future work.« less
Actuators for a space manipulator
NASA Technical Reports Server (NTRS)
Chun, W.; Brunson, P.
1987-01-01
The robotic manipulator can be decomposed into distinct subsytems. One particular area of interest of mechanical subsystems is electromechanical actuators (or drives). A drive is defined as a motor with an appropriate transmission. An overview is given of existing, as well as state-of-the-art drive systems. The scope is limited to space applications. A design philosophy and adequate requirements are the initial steps in designing a space-qualified actuator. The focus is on the d-c motor in conjunction with several types of transmissions (harmonic, tendon, traction, and gear systems). The various transmissions will be evaluated and key performance parameters will be addressed in detail. Included in the assessment is a shuttle RMS joint and a MSFC drive of the Prototype Manipulator Arm. Compound joints are also investigated. Space imposes a set of requirements for designing a high-performance drive assembly. Its inaccessibility and cryogenic conditions warrant special considerations. Some guidelines concerning these conditions are present. The goal is to gain a better understanding in designing a space actuator.
Medical and Transmission Vector Vocabulary Alignment with Schema.org
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, William P.; Chappell, Alan R.; Corley, Courtney D.
Available biomedical ontologies and knowledge bases currently lack formal and standards-based interconnections between disease, disease vector, and drug treatment vocabularies. The PNNL Medical Linked Dataset (PNNL-MLD) addresses this gap. This paper describes the PNNL-MLD, which provides a unified vocabulary and dataset of drug, disease, side effect, and vector transmission background information. Currently, the PNNL-MLD combines and curates data from the following research projects: DrugBank, DailyMed, Diseasome, DisGeNet, Wikipedia Infobox, Sider, and PharmGKB. The main outcomes of this effort are a dataset aligned to Schema.org, including a parsing framework, and extensible hooks ready for integration with selected medical ontologies. The PNNL-MLDmore » enables researchers more quickly and easily to query distinct datasets. Future extensions to the PNNL-MLD will include Traditional Chinese Medicine, broader interlinks across genetic structures, a larger thesaurus of synonyms and hypernyms, explicit coding of diseases and drugs across research systems, and incorporating vector-borne transmission vocabularies.« less
Wheeling and Banking Strategies for Optimal Renewable Energy Deployment. International Experiences
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heeter, Jenny; Vora, Ravi; Mathur, Shivani
This paper defines the principles of wheeling (i.e., transmission) tariffs and renewable energy (RE) banking provisions and their role in RE deployment in countries with plans for large-scale RE. It reviews experiences to date in the United States, Mexico, and India and discusses key policy and regulatory considerations for devising more effective wheeling and/or banking provisions for countries with ambitious RE deployment targets. The paper addresses the challenges of competing needs of stakeholders, especially those of RE generators, distribution utilities, and transmission network owners and operators. The importance of wheeling and banking and their effectiveness for financial viability of REmore » deployment is also explored. This paper aims to benefit policymakers and regulators as well as key renewable energy stakeholders. Key lessons for regulators include: creating long-term wheeling and banking policy certainty, considering incentivizing RE through discounted transmission access, and assessing the cost implications of such discounts, as well as expanding access to renewable energy customers.« less
Mindry, Deborah; Wanyenze, Rhoda K; Beyeza-Kashesya, Jolly; Woldetsadik, Mahlet A; Finocchario-Kessler, Sarah; Goggin, Kathy; Wagner, Glenn
2017-08-01
In countries with high HIV prevalence and high fertility desires, the rights of HIV-affected couples to have children are a pressing issue. Conception among people living with HIV carries risks for both horizontal and vertical HIV transmission. In Uganda ~100,000 HIV-infected women become pregnant annually. Providers face a number of challenges to preventing HIV transmission, reducing unplanned pregnancies, and ensuring safer conception. We report findings from interviews with 27 HIV-affected couples (54 individuals) in Uganda. We explored key cultural and structural factors shaping couples' childbearing decisions. Our data reveal a complex intersection of gender norms, familial expectations, relationship dynamics, and HIV stigma influencing their decisions. Participants provided insights regarding provider bias, stigma, and the gendering of reproductive healthcare. To reduce horizontal transmission HIV and family planning clinics must address men's and women's concerns regarding childbearing with specific attention to cultural and structural challenges.
Shuper, Paul A; Kiene, Susan M; Mahlase, Gethwana; MacDonald, Susan; Christie, Sarah; Cornman, Deborah H; Fisher, William A; Greener, Ross; Lalloo, Umesh G; Pillay, Sandy; van Loggerenberg, Francois; Fisher, Jeffrey D
2014-08-01
The aim of this investigation was to identify factors associated with HIV transmission risk behavior among HIV-positive women and men receiving antiretroviral therapy (ART) in KwaZulu-Natal, South Africa. Across 16 clinics, 1,890 HIV+ patients on ART completed a risk-focused audio computer-assisted self-interview upon enrolling in a prevention-with-positives intervention trial. Results demonstrated that 62 % of HIV-positive patients' recent unprotected sexual acts involved HIV-negative or HIV status unknown partners. For HIV-positive women, multivariable correlates of unprotected sex with HIV-negative or HIV status unknown partners were indicative of poor HIV prevention-related information and of sexual partnership-associated behavioral skills barriers. For HIV-positive men, multivariable correlates represented motivational barriers, characterized by negative condom attitudes and the experience of depressive symptomatology, as well as possible underlying information deficits. Findings suggest that interventions addressing gender-specific and culturally-relevant information, motivation, and behavioral skills barriers could help reduce HIV transmission risk behavior among HIV-positive South Africans.
Analyzing and Detecting Problems in Systems of Systems
NASA Technical Reports Server (NTRS)
Lindvall, Mikael; Ackermann, Christopher; Stratton, William C.; Sibol, Deane E.; Godfrey, Sally
2008-01-01
Many software systems are evolving complex system of systems (SoS) for which inter-system communication is mission-critical. Evidence indicates that transmission failures and performance issues are not uncommon occurrences. In a NASA-supported Software Assurance Research Program (SARP) project, we are researching a new approach addressing such problems. In this paper, we are presenting an approach for analyzing inter-system communications with the goal to uncover both transmission errors and performance problems. Our approach consists of a visualization and an evaluation component. While the visualization of the observed communication aims to facilitate understanding, the evaluation component automatically checks the conformance of an observed communication (actual) to a desired one (planned). The actual and the planned are represented as sequence diagrams. The evaluation algorithm checks the conformance of the actual to the planned diagram. We have applied our approach to the communication of aerospace systems and were successful in detecting and resolving even subtle and long existing transmission problems.
Vertebrate Reservoirs of Arboviruses: Myth, Synonym of Amplifier, or Reality?
Kuno, Goro; Mackenzie, John S.; Plyusnin, Alexander; Gubler, Duane J.
2017-01-01
The rapid succession of the pandemic of arbovirus diseases, such as dengue, West Nile fever, chikungunya, and Zika fever, has intensified research on these and other arbovirus diseases worldwide. Investigating the unique mode of vector-borne transmission requires a clear understanding of the roles of vertebrates. One major obstacle to this understanding is the ambiguity of the arbovirus definition originally established by the World Health Organization. The paucity of pertinent information on arbovirus transmission at the time contributed to the notion that vertebrates played the role of reservoir in the arbovirus transmission cycle. Because this notion is a salient feature of the arbovirus definition, it is important to reexamine its validity. This review addresses controversial issues concerning vertebrate reservoirs and their role in arbovirus persistence in nature, examines the genesis of the problem from a historical perspective, discusses various unresolved issues from multiple points of view, assesses the present status of the notion in light of current knowledge, and provides options for a solution to resolve the issue. PMID:28703771
Vertebrate Reservoirs of Arboviruses: Myth, Synonym of Amplifier, or Reality?
Kuno, Goro; Mackenzie, John S; Junglen, Sandra; Hubálek, Zdeněk; Plyusnin, Alexander; Gubler, Duane J
2017-07-13
The rapid succession of the pandemic of arbovirus diseases, such as dengue, West Nile fever, chikungunya, and Zika fever, has intensified research on these and other arbovirus diseases worldwide. Investigating the unique mode of vector-borne transmission requires a clear understanding of the roles of vertebrates. One major obstacle to this understanding is the ambiguity of the arbovirus definition originally established by the World Health Organization. The paucity of pertinent information on arbovirus transmission at the time contributed to the notion that vertebrates played the role of reservoir in the arbovirus transmission cycle. Because this notion is a salient feature of the arbovirus definition, it is important to reexamine its validity. This review addresses controversial issues concerning vertebrate reservoirs and their role in arbovirus persistence in nature, examines the genesis of the problem from a historical perspective, discusses various unresolved issues from multiple points of view, assesses the present status of the notion in light of current knowledge, and provides options for a solution to resolve the issue.
Vital Signs: Preparing for Local Mosquito-Borne Transmission of Zika Virus--United States, 2016.
2016-04-08
Widespread Zika virus transmission in the Region of the Americas since 2015 has heightened the urgency of preparing for the possibility of expansion of mosquito-borne transmission of Zika virus during the 2016 mosquito season. CDC and other U.S. government agencies have been working with state and local government partners on prevention and early detection of Zika virus infection and will increase these activities during April as part of their preparation for the anticipated emergence of mosquito-borne transmission of Zika virus in the continental United States.
Putting copper into action: copper-impregnated products with potent biocidal activities.
Borkow, Gadi; Gabbay, Jeffrey
2004-11-01
Copper ions, either alone or in copper complexes, have been used for centuries to disinfect liquids, solids, and human tissue. Today copper is used as a water purifier, algaecide, fungicide, nematocide, molluscicide, and antibacterial and antifouling agent. Copper also displays potent antiviral activity. We hypothesized that introducing copper into clothing, bedding, and other articles would provide them with biocidal properties. A durable platform technology has been developed that introduces copper into cotton fibers, latex, and other polymeric materials. This study demonstrates the broad-spectrum antimicrobial (antibacterial, antiviral, antifungal) and antimite activities of copper-impregnated fibers and polyester products. This technology enabled the production of antiviral gloves and filters (which deactivate HIV-1 and other viruses), antibacterial self-sterilizing fabrics (which kill antibiotic-resistant bacteria, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci), antifungal socks (which alleviate symptoms of athlete's foot), and anti-dust mite mattress covers (which reduce mite-related allergies). These products did not have skin-sensitizing properties, as determined by guine pig maximization and rabbit skin irritation tests. Our study demonstrates the potential use of copper in new applications. These applications address medical issues of the greatest importance, such as viral transmissions; nosocomial, or healthcare-associated, infections; and the spread of antibiotic-resistant bacteria.
Harawa, Nina T.; Ramamurthi, Hema Codathi; Bingham, Trista A.
2006-01-01
Disproportionately high HIV/AIDS rates and frequent non-gay identification (NGI) among African American men who have sex with men or with both men and women (MSM/W) highlight the importance of understanding how HIV-positive African American MSM/W perceive safer sex, experience living with HIV, and decide to disclose their HIV status. Thirty predominately seropositive and non-gay identifying African American MSM/W in Los Angeles participated in three semi-structured focus group interviews, and a constant comparison method was used to analyze responses regarding condom use, sexual activity after an HIV diagnosis, and HIV serostatus disclosure. Condom use themes included its protective role against disease and pregnancy, acceptability concerns pertaining to aesthetic factors and effectiveness, and situational influences such as exchange sex, substance use, and suspicions from female partners. Themes regarding the impact of HIV on sexual activity included rejection, decreased partner seeking, and isolation. Serostatus disclosure themes included disclosure to selective partners and personal responsibility. Comprehensive HIV risk-reduction strategies that build social support networks, condom self-efficacy, communication skills, and a sense of collective responsibility among NGI African American MSM/W while addressing HIV stigma in the African American community as a whole are suggested. PMID:16736115
Li, Mei; Andersson-Lendahl, Monika; Sejersen, Thomas; Arner, Anders
2013-03-01
Skeletal muscle was examined in zebrafish larvae in order to address questions related to the function of the intermediate filament protein desmin and its role in the pathogenesis of human desminopathy. A novel approach including mechanical and structural studies of 4-6-d-old larvae was applied. Morpholino antisense oligonucleotides were used to knock down desmin. Expression was assessed using messenger RNA and protein analyses. Histology and synchrotron light-based small angle x-ray diffraction were applied. Functional properties were analyzed with in vivo studies of swimming behavior and with in vitro mechanical examinations of muscle. The two desmin genes normally expressed in zebrafish could be knocked down by ~50%. This resulted in a phenotype with disorganized muscles with altered attachments to the myosepta. The knockdown larvae were smaller and had diminished swimming activity. Active tension was lowered and muscles were less vulnerable to acute stretch-induced injury. X-ray diffraction revealed wider interfilament spacing. In conclusion, desmin intermediate filaments are required for normal active force generation and affect vulnerability during eccentric work. This is related to the role of desmin in anchoring sarcomeres for optimal force transmission. The results also show that a partial lack of desmin, without protein aggregates, is sufficient to cause muscle pathology resembling that in human desminopathy.
Johnson, Oshea D.
2015-01-01
Objectives. We examined associations between homonegative attitudes and HIV and other sexually transmitted infection (HIV/STI) risk behaviors among sexually active US men. Methods. We used the 2006–2010 National Survey of Family Growth (n = 10 403) and multivariable logistic regression models to examine homonegative attitudes in relation to condom use, number of past-year sex partners, HIV/STI testing, and STI diagnoses. Results. Among men who had sex with men, homonegative attitudes were associated with lower odds of condom use during anal sex with women (before the past year) and past-year STI testing. Among men who had sex with men and women, homonegative attitudes were associated with lower odds of condom use during vaginal sex and sex with men, having 4 or more partners, and HIV testing ever. Among men who had sex with women, homonegative attitudes were associated with lower odds of condom use during vaginal sex and sex with men (before the past year), HIV testing ever, and contracting herpes, human papillomavirus, or syphilis. Conclusions. Homonegative attitudes may promote HIV/STI acquisition and transmission among sexually active men of all sexual orientations. Interventions should address homonegative attitudes in the United States. PMID:26469637
Musoke, Pamela; Hatcher, Abigail; Rogers, Anna Joy; Achiro, Lillian; Bukusi, Elizabeth; Darbes, Lynae; Kwena, Zachary; Oyaro, Patrick; Weke, Elly; Turan, Janet M
2018-02-21
Male involvement in antenatal care has been shown to improve health outcomes for women and infants. However, little is known about how best to encourage male partners to support essential perinatal health activities. We explored men's perceptions of facilitators and barriers to involvement in antenatal care and HIV prevention including fears, hopes and challenges. Forty in-depth interviews were conducted with the male partners of HIV-positive and HIV-negative pregnant women in southwest Kenya. Most male partners believed engaging in pregnancy health-related activities was beneficial for keeping families healthy. However, thematic analysis revealed several obstacles that hindered participation. Poor couple relationship dynamics seemed negatively to influence male engagement. Some men were apprehensive that clinic staff might force them to test for HIV and disclose the results; if HIV-positive, men feared being labelled as 'victimisers' in situations of serodiscordancy, and described fears of abandonment by their wives. Some men avoided accompanying their wives, citing local culture as rationale for avoiding the 'effeminate' act of antenatal care attendance. Amidst these obstacles, some men chose to use their partners' HIV status as proxy for their own. Findings suggest that improving male engagement in essential maternal and child health-related activities will require addressing both structural and interpersonal barriers.