Grid sensitivity for aerodynamic optimization and flow analysis

NASA Technical Reports Server (NTRS)

Sadrehaghighi, I.; Tiwari, S. N.

1993-01-01

After reviewing relevant literature, it is apparent that one aspect of aerodynamic sensitivity analysis, namely grid sensitivity, has not been investigated extensively. The grid sensitivity algorithms in most of these studies are based on structural design models. Such models, although sufficient for preliminary or conceptional design, are not acceptable for detailed design analysis. Careless grid sensitivity evaluations, would introduce gradient errors within the sensitivity module, therefore, infecting the overall optimization process. Development of an efficient and reliable grid sensitivity module with special emphasis on aerodynamic applications appear essential. The organization of this study is as follows. The physical and geometric representations of a typical model are derived in chapter 2. The grid generation algorithm and boundary grid distribution are developed in chapter 3. Chapter 4 discusses the theoretical formulation and aerodynamic sensitivity equation. The method of solution is provided in chapter 5. The results are presented and discussed in chapter 6. Finally, some concluding remarks are provided in chapter 7.

Extensions and applications of a second-order landsurface parameterization

NASA Technical Reports Server (NTRS)

Andreou, S. A.; Eagleson, P. S.

1983-01-01

Extensions and applications of a second order land surface parameterization, proposed by Andreou and Eagleson are developed. Procedures for evaluating the near surface storage depth used in one cell land surface parameterizations are suggested and tested by using the model. Sensitivity analysis to the key soil parameters is performed. A case study involving comparison with an "exact" numerical model and another simplified parameterization, under very dry climatic conditions and for two different soil types, is also incorporated.

Coupled Aerodynamic and Structural Sensitivity Analysis of a High-Speed Civil Transport

NASA Technical Reports Server (NTRS)

Mason, B. H.; Walsh, J. L.

2001-01-01

An objective of the High Performance Computing and Communication Program at the NASA Langley Research Center is to demonstrate multidisciplinary shape and sizing optimization of a complete aerospace vehicle configuration by using high-fidelity, finite-element structural analysis and computational fluid dynamics aerodynamic analysis. In a previous study, a multi-disciplinary analysis system for a high-speed civil transport was formulated to integrate a set of existing discipline analysis codes, some of them computationally intensive, This paper is an extension of the previous study, in which the sensitivity analysis for the coupled aerodynamic and structural analysis problem is formulated and implemented. Uncoupled stress sensitivities computed with a constant load vector in a commercial finite element analysis code are compared to coupled aeroelastic sensitivities computed by finite differences. The computational expense of these sensitivity calculation methods is discussed.

COPPER PITTING AND PINHOLE LEAK RESEARCH STUDY

EPA Science Inventory

Localized copper corrosion or pitting is a significant problem at many water utilities across the United States. Copper pinhole leak problems resulting from extensive pitting are widely under reported. Given the sensitive nature of the problem, extent of damage possible, costs o...

Extension of the Thoracic Spine Sign: A New Sonographic Marker of Pleural Effusion.

PubMed

Dickman, Eitan; Terentiev, Victoria; Likourezos, Antonios; Derman, Anna; Haines, Lawrence

2015-09-01

Dyspnea is a common emergency department (ED) condition, which may be caused by pleural effusion and other thoracic diseases. We present data on a new sonographic marker, the extension of the thoracic spine sign, for diagnosis of pleural effusion. In this prospective study, we enrolled a convenience sample of undifferentiated patients who underwent computed tomography (CT) of the abdomen or chest, which was performed as part of their emergency department evaluations. Patients underwent chest sonography to assess the utility of the extension of the thoracic spine sign for diagnosing pleural effusion. The point-of-care sonographic examinations were performed and interpreted by emergency physicians who were blinded to information in the medical records. Sonographic results were compared to radiologists' interpretations of the CT results, which were considered the criterion standard. Forty-one patients were enrolled, accounting for 82 hemithoraces. Seven hemithoraces were excluded from the analysis due to various limitations, leaving 75 hemithoraces for the final analysis. The median time for completion of the sonographic examination was 3 minutes. The sensitivity and specificity for extension of the thoracic spine were 73.7% (95% confidence interval [CI], 48.6%-89.9%) and 92.9% (95%CI, 81.9%-97.7%), respectively. Overall, there were 5 hemithoraces with false-negative results when using the extension sign. Of those 5 cases, 4 were found to have trace pleural effusions on CT. When trace pleural effusions were excluded in a subgroup analysis, the sensitivity and specificity of extension of the thoracic spine were 92.9% (95% CI, 64.2%-99.6%) and 92.9% (95% CI, 81.9%-97.7%). We found the extension of the thoracic spine sign to be an excellent diagnostic tool for clinically relevant pleural effusion. © 2015 by the American Institute of Ultrasound in Medicine.

Gender-Sensitive Approaches to Extension Programme Design

ERIC Educational Resources Information Center

Jafry, Tahseen; Sulaiman, V. Rasheed

2013-01-01

Purpose: Though women are engaged in farming and play a major role in almost every agricultural operation, they continue to receive very limited extension support. While several interventions have been made to address this "gender" bias in extension delivery, there continues to be a shortfall between the kind of support that is provided…

Protocol for the use of light upon extension real-time PCR for the determination of viral load in HBV infection.

PubMed

Li, Guimin; Li, Wangfeng; Liu, Lixia

2012-01-01

Real-time PCR has engendered wide acceptance for quantitation of hepatitis B virus (HBV) DNA in the blood due to its improved rapidity, sensitivity, reproducibility, and reduced contamination. Here we describe a cost-effective and highly sensitive HBV real-time quantitative assay based on the light upon extension real-time PCR platform and a simple and reliable HBV DNA preparation method using silica-coated magnetic beads.

Ecological consequences of antibiotic exposure to periphyton in naturally colonizing stream mesocosms

EPA Science Inventory

Tetracycline and its derivatives are extensively used human and animal antibiotics, and enter stream ecosystems via point and non-point sources. Laboratory studies indicate that microbial organisms are more sensitive to antibiotics than invertebrates or fish, and may indicate t...

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis :

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

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S.

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a user's manual for the Dakota software and provides capability overviews and procedures for software execution, as well as a variety of example studies.« less

Polymerase chain displacement reaction.

PubMed

Harris, Claire L; Sanchez-Vargas, Irma J; Olson, Ken E; Alphey, Luke; Fu, Guoliang

2013-02-01

Quantitative PCR assays are now the standard method for viral diagnostics. These assays must be specific, as well as sensitive, to detect the potentially low starting copy number of viral genomic material. We describe a new technique, polymerase chain displacement reaction (PCDR), which uses multiple nested primers in a rapid, capped, one-tube reaction that increases the sensitivity of normal quantitative PCR (qPCR) assays. Sensitivity was increased by approximately 10-fold in a proof-of-principle test on dengue virus sequence. In PCDR, when extension occurs from the outer primer, it displaces the extension strand produced from the inner primer by utilizing a polymerase that has strand displacement activity. This allows a greater than 2-fold increase of amplification product for each amplification cycle and therefore increased sensitivity and speed over conventional PCR. Increased sensitivity in PCDR would be useful in nucleic acid detection for viral diagnostics.

Pain sensitivity and tactile spatial acuity are altered in healthy musicians as in chronic pain patients

PubMed Central

Zamorano, Anna M.; Riquelme, Inmaculada; Kleber, Boris; Altenmüller, Eckart; Hatem, Samar M.; Montoya, Pedro

2015-01-01

Extensive training of repetitive and highly skilled movements, as it occurs in professional classical musicians, may lead to changes in tactile sensitivity and corresponding cortical reorganization of somatosensory cortices. It is also known that professional musicians frequently experience musculoskeletal pain and pain-related symptoms during their careers. The present study aimed at understanding the complex interaction between chronic pain and music training with respect to somatosensory processing. For this purpose, tactile thresholds (mechanical detection, grating orientation, two-point discrimination) and subjective ratings to thermal and pressure pain stimuli were assessed in 17 professional musicians with chronic pain, 30 pain-free musicians, 20 non-musicians with chronic pain, and 18 pain-free non-musicians. We found that pain-free musicians displayed greater touch sensitivity (i.e., lower mechanical detection thresholds), lower tactile spatial acuity (i.e., higher grating orientation thresholds) and increased pain sensitivity to pressure and heat compared to pain-free non-musicians. Moreover, we also found that musicians and non-musicians with chronic pain presented lower tactile spatial acuity and increased pain sensitivity to pressure and heat compared to pain-free non-musicians. The significant increment of pain sensitivity together with decreased spatial discrimination in pain-free musicians and the similarity of results found in chronic pain patients, suggests that the extensive training of repetitive and highly skilled movements in classical musicians could be considered as a risk factor for developing chronic pain, probably due to use-dependent plastic changes elicited in somatosensory pathways. PMID:25610384

Characterization and limits of a cold-atom Sagnac interferometer

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

Gauguet, A.; Canuel, B.; Leveque, T.

2009-12-15

We present the full evaluation of a cold-atom gyroscope based on atom interferometry. We have performed extensive studies to determine the systematic errors, scale factor and sensitivity. We demonstrate that the acceleration noise can be efficiently removed from the rotation signal, allowing us to reach the fundamental limit of the quantum projection noise for short term measurements. The technical limits to the long term sensitivity and accuracy have been identified, clearing the way for the next generation of ultrasensitive atom gyroscopes.

Nano-textured high sensitivity ion sensitive field effect transistors

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

Hajmirzaheydarali, M.; Sadeghipari, M.; Akbari, M.

2016-02-07

Nano-textured gate engineered ion sensitive field effect transistors (ISFETs), suitable for high sensitivity pH sensors, have been realized. Utilizing a mask-less deep reactive ion etching results in ultra-fine poly-Si features on the gate of ISFET devices where spacing of the order of 10 nm and less is achieved. Incorporation of these nano-sized features on the gate is responsible for high sensitivities up to 400 mV/pH in contrast to conventional planar structures. The fabrication process for this transistor is inexpensive, and it is fully compatible with standard complementary metal oxide semiconductor fabrication procedure. A theoretical modeling has also been presented to predict themore » extension of the diffuse layer into the electrolyte solution for highly featured structures and to correlate this extension with the high sensitivity of the device. The observed ultra-fine features by means of scanning electron microscopy and transmission electron microscopy tools corroborate the theoretical prediction.« less

Reduction of substituted p-Benzoquinones by Fe II near neutral pH

USDA-ARS?s Scientific Manuscript database

The oxidation of dihydroxyaromatics to benzoquinones by FeIII (hydr)oxides is important in respiratory electron shuttling by microorganisms and has been extensively studied. Prior publications have noted that the Gibbs Free Energy (DG) for the forward reaction is sensitive to dihydroxyaromatic struc...

75 FR 63499 - Extension of Agency Information Collection Activity Under OMB Review: Sensitive Security...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-15

... Information Collection Activity Under OMB Review: Sensitive Security Information Threat Assessments AGENCY... Transportation Security Administration (TSA) has forwarded the Information Collection Request (ICR), Office of... of a party seeking access to sensitive security information (SSI) in a civil proceeding in Federal...

Diagnosing the impact of alternative calibration strategies on coupled hydrologic models

NASA Astrophysics Data System (ADS)

Smith, T. J.; Perera, C.; Corrigan, C.

2017-12-01

Hydrologic models represent a significant tool for understanding, predicting, and responding to the impacts of water on society and society on water resources and, as such, are used extensively in water resources planning and management. Given this important role, the validity and fidelity of hydrologic models is imperative. While extensive focus has been paid to improving hydrologic models through better process representation, better parameter estimation, and better uncertainty quantification, significant challenges remain. In this study, we explore a number of competing model calibration scenarios for simple, coupled snowmelt-runoff models to better understand the sensitivity / variability of parameterizations and its impact on model performance, robustness, fidelity, and transferability. Our analysis highlights the sensitivity of coupled snowmelt-runoff model parameterizations to alterations in calibration approach, underscores the concept of information content in hydrologic modeling, and provides insight into potential strategies for improving model robustness / fidelity.

Groundwater sensitivity mapping in Kentucky using GIS and digitally vectorized geologic quadrangles

NASA Astrophysics Data System (ADS)

Croskrey, Andrea; Groves, Chris

2008-05-01

Groundwater sensitivity (Ray and O’dell in Environ Geol 22:345 352, 1993a) refers to the inherent ease with which groundwater can be contaminated based on hydrogeologic characteristics. We have developed digital methods for identifying areas of varying groundwater sensitivity for a ten county area of south central Kentucky at a scale of 1:100,000. The study area includes extensive limestone karst sinkhole plains, with groundwater extremely sensitive to contamination. Digitally vectorized geologic quadrangles (DVGQs) were combined with elevation data to identify both hydrogeologic groundwater sensitivity regions and zones of “high risk runoff” where contaminants could be transported in runoff from less sensitive to higher sensitivity (particularly karst) areas. While future work will fine-tune these maps with additional layers of data (soils for example) as digital data have become available, using DVGQs allows a relatively rapid assessment of groundwater sensitivity for Kentucky at a more useful scale than previously available assessment methods, such as DRASTIC and DIVERSITY.

Genetic moderation of effects of maternal sensitivity on girl's age of menarche: Replication of the Manuck et al. study.

PubMed

Hartman, Sarah; Widaman, Keith F; Belsky, Jay

2015-08-01

Manuck, Craig, Flory, Halder, and Ferrell (2011) reported that a theoretically anticipated effect of family rearing on girls' menarcheal age was genetically moderated by two single nucleotide polymorphisms (SNPs) of the estrogen receptor-α gene. We sought to replicate and extend these findings, studying 210 White females followed from birth. The replication was general because a different measure of the rearing environment was used in this inquiry (i.e., maternal sensitivity) than in the prior one (i.e., family cohesion). Extensions of the work included prospective rather than retrospective measurements of the rearing environment, reports of first menstruation within a year of its occurrence rather than decades later, accounting for some heritability of menarcheal age by controlling for maternal age of menarche, and using a new model-fitting approach to competitively compare diathesis-stress versus differential-susceptibility models of Gene × Environment interaction. The replication/extension effort proved successful in the case of both estrogen receptor-α SNPs, with the Gene × Environment interactions principally reflecting diathesis-stress: lower levels of maternal sensitivity predicted earlier age of menarche for girls homozygous for the minor alleles of either SNP but not for girls carrying other genotypes. Results are discussed in light of the new analytic methods adopted.

Solar chemistry of metal complexes

NASA Astrophysics Data System (ADS)

Gray, H. B.; Maverick, A. W.

1981-12-01

Electronic excited states of certain transition metal complexes undergo oxidation-reduction reactions that store chemical energy. Such reactions have been extensively explored for mononuclear complexes. Two classes of polynuclear species exhibit similar properties, and these complexes are now being studied as possible homogeneous sensitizer-catalysts for hydrogen production from aqueous solutions.

INVERSE MODELING TO ESTIMATE NH3 EMISSION SEASONALLY AND THE SENSITIVITY TO UNCERTAINTY REPRESENTATIONS

EPA Science Inventory

Inverse modeling has been used extensively on the global scale to produce top-down estimates of emissions for chemicals such as CO and CH4. Regional scale air quality studies could also benefit from inverse modeling as a tool to evaluate current emission inventories; however, ...

Hyper-Acetylation of Histone H3K56 Limits Break-Induced Replication by Inhibiting Extensive Repair Synthesis

PubMed Central

Che, Jun; Smith, Stephanie; Kim, Yoo Jung; Shim, Eun Yong; Myung, Kyungjae; Lee, Sang Eun

2015-01-01

Break-induced replication (BIR) has been implicated in restoring eroded telomeres and collapsed replication forks via single-ended invasion and extensive DNA synthesis on the recipient chromosome. Unlike other recombination subtypes, DNA synthesis in BIR likely relies heavily on mechanisms enabling efficient fork progression such as chromatin modification. Herein we report that deletion of HST3 and HST4, two redundant de-acetylases of histone H3 Lysine 56 (H3K56), inhibits BIR, sensitizes checkpoint deficient cells to deoxyribonucleotide triphosphate pool depletion, and elevates translocation-type gross chromosomal rearrangements (GCR). The basis for deficiency in BIR and gene conversion with long gap synthesis in hst3Δ hst4Δ cells can be traced to a defect in extensive DNA synthesis. Distinct from other cellular defects associated with deletion of HST3 and HST4 including thermo-sensitivity and elevated spontaneous mutagenesis, the BIR defect in hst3Δ hst4Δ cannot be offset by the deletion of RAD17 or MMS22, but rather by the loss of RTT109 or ASF1, or in combination with the H3K56R mutation, which also restores tolerance to replication stress in mrc1 mutants. Our studies suggest that acetylation of H3K56 limits extensive repair synthesis and interferes with efficient fork progression in BIR. PMID:25705897

Differential cellular responses in healthy mice and in mice with established airway inflammation when exposed to hematite nanoparticles

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

Gustafsson, Åsa, E-mail: asa.gustafsson@foi.se; Dept of Public Health and Clinical Medicine, Umeå University; Bergström, Ulrika

The aim of this study was to investigate the inflammatory and immunological responses in airways and lung-draining lymph nodes (LDLNs), following lung exposure to iron oxide (hematite) nanoparticles (NPs). The responses to the hematite NPs were evaluated in both healthy non-sensitized mice, and in sensitized mice with an established allergic airway disease. The mice were exposed intratracheally to either hematite NPs or to vehicle (PBS) and the cellular responses were evaluated on days 1, 2, and 7, post-exposure. Exposure to hematite NPs increased the numbers of neutrophils, eosinophils, and lymphocytes in the airways of non-sensitized mice on days 1 andmore » 2 post-exposure; at these time points the number of lymphocytes was also elevated in the LDLNs. In contrast, exposing sensitized mice to hematite NPs induced a rapid and unspecific cellular reduction in the alveolar space on day 1 post-exposure; a similar decrease of lymphocytes was also observed in the LDLN. The results indicate that cells in the airways and in the LDLN of individuals with established airway inflammation undergo cell death when exposed to hematite NPs. A possible explanation for this toxic response is the extensive generation of reactive oxygen species (ROS) in the pro-oxidative environment of inflamed airways. This study demonstrates how sensitized and non-sensitized mice respond differently to hematite NP exposure, and it highlights the importance of including individuals with respiratory disorders when evaluating health effects of inhaled nanomaterials. - Highlights: • Hematite NPs induce differential responses in airways of healthy and allergic mice. • Hematite induced an airway inflammation in healthy mice. • Hematite induced cellular reduction in the alveolus and lymph nodes of allergic mice. • Cell death is possible due to extensive pro-oxidative environment in allergic mice. • It is important to include sensitive individuals when valuing health effects of NPs.« less

In Vivo Patellofemoral Contact Mechanics During Active Extension Using a Novel Dynamic MRI-based Methodology

PubMed Central

Borotikar, Bhushan S.; Sheehan, Frances T.

2017-01-01

Objectives To establish an in vivo, normative patellofemoral cartilage contact mechanics database acquired during voluntary muscle control using a novel dynamic magnetic resonance (MR) imaging-based computational methodology and validate the contact mechanics sensitivity to the known sub-millimeter methodological inaccuracies. Design Dynamic cine phase-contrast and multi-plane cine images were acquired while female subjects (n=20, sample of convenience) performed an open kinetic chain (knee flexion-extension) exercise inside a 3-Tesla MR scanner. Static cartilage models were created from high resolution three-dimensional static MR data and accurately placed in their dynamic pose at each time frame based on the cine-PC data. Cartilage contact parameters were calculated based on the surface overlap. Statistical analysis was performed using paired t-test and a one-sample repeated measures ANOVA. The sensitivity of the contact parameters to the known errors in the patellofemoral kinematics was determined. Results Peak mean patellofemoral contact area was 228.7±173.6mm2 at 40° knee angle. During extension, contact centroid and peak strain locations tracked medially on the femoral and patellar cartilage and were not significantly different from each other. At 30°, 35°, and 40° of knee extension, contact area was significantly different. Contact area and centroid locations were insensitive to rotational and translational perturbations. Conclusion This study is a first step towards unfolding the biomechanical pathways to anterior patellofemoral pain and OA using dynamic, in vivo, and accurate methodologies. The database provides crucial data for future studies and for validation of, or as an input to, computational models. PMID:24012620

Addition of lateral bending range of motion measurement to standard sagittal measurement to improve diagnosis sensitivity of ligamentous injury in the human lower cervical spine.

PubMed

Leahy, P Devin; Puttlitz, Christian M

2016-01-01

This study examined the cervical spine range of motion (ROM) resulting from whiplash-type hyperextension and hyperflexion type ligamentous injuries, and sought to improve the accuracy of specific diagnosis of these injuries. The study was accomplished by measurement of ROM throughout axial rotation, lateral bending, and flexion and extension, using a validated finite element model of the cervical spine that was modified to simulate hyperextension and/or hyperflexion injuries. It was found that the kinematic difference between hyperextension and hyperflexion injuries was minimal throughout the combined flexion and extension ROM measurement that is commonly used for clinical diagnosis of cervical ligamentous injury. However, the two injuries demonstrated substantially different ROM under axial rotation and lateral bending. It is recommended that other bending axes beyond flexion and extension are incorporated into clinical diagnosis of cervical ligamentous injury.

Infant Auditory Sensitivity to Pure Tones and Frequency-Modulated Tones

ERIC Educational Resources Information Center

Leibold, Lori J.; Werner, Lynne A.

2007-01-01

It has been suggested that infants respond preferentially to infant-directed speech because their auditory sensitivity to sounds with extensive frequency modulation (FM) is better than their sensitivity to less modulated sounds. In this experiment, auditory thresholds for FM tones and for unmodulated, or pure, tones in a background of noise were…

An ultraviolet light induced bacteriophage in Beneckea gazogenes. [organism growth on precambrian earth

NASA Technical Reports Server (NTRS)

Rambler, M.; Margulis, L.

1979-01-01

The effects of UV and high intensity irradiation on microorganisms growing under conditions prevalent during the early Precambrian Aeon are examined. The study employed the anaerobic red pigmented marine vibrio, Beneckea gazogenes (Harwood, 1978), using an extreme UV sensitivity of 2537 A, extensive cell lysis, and commitant production of bacteriophage induced by the UV light. Three types of white mutant, pink colony mutant, and red wild type isolates of B gazogenes were grown showing differential irradiation sensitivity and phage particles from all three lysates were collected and examined.

Tapered GRIN fiber microsensor.

PubMed

Beltrán-Mejía, Felipe; Biazoli, Claudecir R; Cordeiro, Cristiano M B

2014-12-15

The sensitivity of an optical fiber microsensor based on inter-modal interference can be considerably improved by tapering a short extension of the multimode fiber. In the case of Graded Index fibers with a parabolic refractive index profile, a meridional ray exhibits a sinusoidal path. When these fibers are tapered, the period of the propagated beam decrease down-taper and increase up-taper. We take advantage of this modulation -along with the enhanced overlap between the evanescent field and the external medium- to substantially increase the sensitivity of these devices by tuning the sensor's maximum sensitivity wavelength. Moreover, the extension of this device is reduced by one order of magnitude, making it more propitious for reduced space applications. Numerical and experimental results demonstrate the success and feasibility of this approach.

Bias in the Social Studies Curricula.

ERIC Educational Resources Information Center

Lamott, Stephen

There has always been a traditional bias in the learning materials used in schools. Due to a growing awareness of this bias, educators have become sensitive to the need for change in curricular materials. The trend in textbook publication has been to pretend that discrimination no longer exists in the United States. The extensive textbook…

Sequence analysis of a bitter taste receptor gene repertoires in different ruminant species

USDA-ARS?s Scientific Manuscript database

Bitter taste has been extensively studied in mammalian species and is associated with sensitivity to toxins and with food choices that avoid dangerous substances in the diet. At the molecular level, bitter compounds are sensed by bitter taste receptor proteins (T2R) present at the surface of taste r...

Habituation and Sensitization to Filmed Violence.

ERIC Educational Resources Information Center

Gange, J. J.; And Others

In an extension of an earlier study by Cline, Croft, and Courrier (1973) the effects of amount of television viewing and preference for televised violence upon autonomic responses to violent and nonviolent videotaped movie sequences were examined. Thirty-six male undergraduates watched a six-minute portion of a boxing film and a six-minute portion…

STUDIES OF TWO KINDS OF VIRUS PARTICLES WHICH COMPRISE INFLUENZA A2 VIRUS STRAINS

PubMed Central

Choppin, Purnell W.; Tamm, Igor

1960-01-01

Two kinds of virus particles have been found in varying proportions in influenza A2 strains isolated during the 1957 pandemic. Pure populations of the different particles were obtained, and these substrains were genetically stable on serial passage in the chick embryo. The two virus particles differ markedly in several biological properties though they are antigenically similar. One kind of particle, designated "+," is relatively sensitive to specific antibody, is highly sensitive to inhibition by serum inhibitors and urinary mucoprotein, fails to elute or elutes very slowly from human erythrocytes, and is capable of agglutinating erythrocytes treated extensively with V. cholerae filtrate. The other particle, designated "-," is relatively insensitive to antibodies and urinary mucoprotein, completely insensitive to serum inhibitors, elutes rapidly from erythrocytes, and can agglutinate erythrocytes treated extensively with V. cholerae filtrate. Both "+" and "-" particles destroy virus receptors on urinary mucoprotein. The relative proportions of these two particles determine the characteristics of parent strains in reactions with specific antibody, mucoprotein inhibitors, and erythrocytes. The "+" and "-" particles with several easily identifiable markers are well suited for genetic studies. PMID:19867182

Sensitivity-Enhanced Wearable Active Voiceprint Sensor Based on Cellular Polypropylene Piezoelectret.

PubMed

Li, Wenbo; Zhao, Sheng; Wu, Nan; Zhong, Junwen; Wang, Bo; Lin, Shizhe; Chen, Shuwen; Yuan, Fang; Jiang, Hulin; Xiao, Yongjun; Hu, Bin; Zhou, Jun

2017-07-19

Wearable active sensors have extensive applications in mobile biosensing and human-machine interaction but require good flexibility, high sensitivity, excellent stability, and self-powered feature. In this work, cellular polypropylene (PP) piezoelectret was chosen as the core material of a sensitivity-enhanced wearable active voiceprint sensor (SWAVS) to realize voiceprint recognition. By virtue of the dipole orientation control method, the air layers in the piezoelectret were efficiently utilized, and the current sensitivity was enhanced (from 1.98 pA/Hz to 5.81 pA/Hz at 115 dB). The SWAVS exhibited the superiorities of high sensitivity, accurate frequency response, and excellent stability. The voiceprint recognition system could make correct reactions to human voices by judging both the password and speaker. This study presented a voiceprint sensor with potential applications in noncontact biometric recognition and safety guarantee systems, promoting the progress of wearable sensor networks.

Is Andrographis paniculata extract and andrographolide anaphylactic?

PubMed

Richard, Edwin Jothie; Murugan, Sasikumar; Bethapudi, Bharathi; Illuri, Ramanaiah; Mundkinajeddu, Deepak; Chinampudur Velusami, Chandrasekaran

2017-01-01

Andrographis paniculata, "King of bitters" is a popularly known medicinal plant extensively used in many parts of the world for treatment of various diseases. Since recent past, anaphylactic/allergic type adverse events were reported upon A. paniculata usage, the study aimed to evaluate the anaphylactic and anaphylactoid potential of A. paniculata extract and andrographolide (a major phytoactive of A. paniculata ). The anaphylactic potential was evaluated using active systemic anaphylaxis (ASA) assay in guinea pigs. Further, the release of allergic mediators was measured in immunoglobulin E (IgE) sensitized and non-IgE sensitized Rat Basophilic Leukemia (RBL-2H3) cell lines in-vitro . A. paniculata extract or andrographolide sensitized guinea pigs following the challenge antigen administration orally and intravenously did not demonstrate any clinical signs of anaphylaxis. IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with A. paniculata extract did not induce release of allergic mediators. Whereas IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with andrographolide demonstrated mild to moderate release of allergic mediators. A. paniculata extract has no anaphylactic and anaphylactoid potential in in-vivo and in-vitro studies. Whereas, andrographolide effects on allergic mediators in in-vitro studies needs to be scrutinized if they are of biologically important.

GIGAS: A set of microwave sensor arrays to detect molecular bremsstrahlung radiation from extensive air shower

NASA Astrophysics Data System (ADS)

Gaïor, R.; Al Samarai, I.; Berat, C.; Blanco Otano, M.; David, J.; Deligny, O.; Lebbolo, H.; Lecoz, S.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Mariş, I. C.; Montanet, F.; Repain, P.; Salamida, F.; Settimo, M.; Stassi, P.; Stutz, A.

2018-04-01

We present the GIGAS (Gigahertz Identification of Giant Air Shower) microwave radio sensor arrays of the EASIER project (Extensive Air Shower Identification with Electron Radiometers), deployed at the site of the Pierre Auger cosmic ray observatory. The aim of these novel arrays is to probe the intensity of the molecular bremsstrahlung radiation expected from the development of the extensive air showers produced by the interaction of ultra high energy cosmic rays in the atmosphere. In the designed setup, the sensors are embedded within the surface detector array of the Pierre Auger observatory allowing us to use the particle signals at ground level to trigger the radio system. A series of seven, then 61 sensors have been deployed in the C-band, followed by a new series of 14 higher sensitivity ones in the C-band and the L-band. The design, the operation, the calibration and the sensitivity to extensive air showers of these arrays are described in this paper.

Extension of the Rejection Sensitivity Construct to the Interpersonal Functioning of Gay Men

ERIC Educational Resources Information Center

Pachankis, John E.; Goldfried, Marvin R.; Ramrattan, Melissa E.

2008-01-01

On the basis of recent evidence suggesting that gay men are particularly likely to fear interpersonal rejection, the authors set out to extend the "rejection sensitivity" construct to the mental health concerns of gay men. After establishing a reliable and valid measure of the gay-related rejection sensitivity construct, the authors use this to…

[Sero-epidemiology of VZV infection in Italy: impact evaluation of extensive vaccination].

PubMed

Gabutti, Giovanni; Rota, Maria Cristina; De Donno, Antonella; Guido, Marcello; Bella, Antonino; Idolo, Adele; Lupi, Silvia; Brignole, Giordana

2014-01-01

Eight Italian Regions have begun offering vaccination against varicella to children aged 13-15 months, with a second dose at 5-6 years of age. A serosurvey was conducted to evaluate the impact of extensive vaccination in these "pilot" Regions. Samples were collected in compliance with current legislation and after the approval of the Ethics Committee. The qualitative and quantitative determination of antibodies (IgG) against varicella was performed using an ELISA assay with high sensitivity and specificity. 1,470 samples were analyzed. After the decrease of seropositivity associated with the decay of passively acquired antibody titer, there was a progressive increase of seroprevalence in the other age groups. The comparison with what was recorded in two studies conducted with similar assays in the periods 1996/97 and 2003/04, showed a significant increase in seroprevalence following extensive immunization, particularly in the age classes 1 year, 2-4 years and 5-9 years. The proportion of seropositivity in the age classes 1 year and 2-4 years has more than doubled. Seroepidemiological studies are a useful tool to evaluate the distribution of susceptible individuals in the population. This study highlighted the impact of extensive vaccination against varicella in eight "pilot" Regions.

A new estimate of detrital redox-sensitive metal concentrations and variability in fluxes to marine sediments

NASA Astrophysics Data System (ADS)

Cole, Devon B.; Zhang, Shuang; Planavsky, Noah J.

2017-10-01

The enrichment and depletion of redox sensitive trace metals in marine sediments have been used extensively as paleoredox proxies. The trace metals in shale are comprised of both detrital (transported or particulate) and authigenic (precipitated, redox-driven) constituents, potentially complicating the use of this suite of proxies. Untangling the influence of these components is vital for the interpretation of enrichments, depletions, and isotopic signals of iron (Fe), chromium (Cr), uranium (U), and vanadium (V) observed in the rock record. Traditionally, a single crustal average is used as a cutoff for detrital input, and concentrations above or below this value are interpreted as redox derived authigenic enrichment or depletion, while authigenic isotopic signals are frequently corrected for an assumed detrital contribution. Building from an extensive study of soils across the continental United States - which upon transport will become marine sediments - and their elemental concentrations, we find large deviations from accepted crustal averages in redox-sensitive metals (Fe, Cr, U, V) compared to typical detrital tracers (Al, Ti, Sc, Th) and provide new estimates for detrital contributions to the ocean. The variability in these elemental ratios is present over large areas, comparable to the catchment-size of major rivers around the globe. This heterogeneity in detrital flux highlights the need for a reevaluation of how the detrital contribution is assessed in trace metal studies, and the use of confidence intervals rather than single average values, especially in local studies or in the case of small authigenic enrichments.

Mefloquine blockade of Pannexin1 currents: Resolution of a conflict

PubMed Central

Iglesias, Rodolfo; Spray, David C.; Scemes, Eliana

2010-01-01

Our laboratory has reported potent block of Pannexin1 (Panx1) currents by the antimalarial quinine derivative mefloquine. However, other laboratories have found little or no mefloquine sensitivity of Panx1 currents or processes attributable to these channels. In order to resolve this issue, we have performed extensive dose-response studies on Panx1 transfected neuroblastoma (Neuro2A) and rat insulinoma (Rin) cells comparing mefloquine obtained from three suppliers and also comparing the sensitivity to diastereomers. Results indicate a twenty-fold difference in sensitivity to the (−)-threo-(11R/2R) diastereomer compared to the erythro enatiomers and much lower potency of (±)-erythro-(R*/S*)-mefloquine obtained from one of the commercial sources. This markedly lower efficacy presumably accounts for the disparity in results from different laboratories who have applied it in Panx1 studies. PMID:20218915

Testing sterile neutrino extensions of the Standard Model at future lepton colliders

NASA Astrophysics Data System (ADS)

Antusch, Stefan; Fischer, Oliver

2015-05-01

Extending the Standard Model (SM) with sterile ("right-handed") neutrinos is one of the best motivated ways to account for the observed neutrino masses. We discuss the expected sensitivity of future lepton collider experiments for probing such extensions. An interesting testable scenario is given by "symmetry protected seesaw models", which theoretically allow for sterile neutrino masses around the electroweak scale with up to order one mixings with the light (SM) neutrinos. In addition to indirect tests, e.g. via electroweak precision observables, sterile neutrinos with masses around the electroweak scale can also be probed by direct searches, e.g. via sterile neutrino decays at the Z pole, deviations from the SM cross section for four lepton final states at and beyond the WW threshold and via Higgs boson decays. We study the present bounds on sterile neutrino properties from LEP and LHC as well as the expected sensitivities of possible future lepton colliders such as ILC, CEPC and FCC-ee (TLEP).

Orbital transfer vehicle concept definition and system analysis study, 1986. Volume 9: Study extension results

NASA Technical Reports Server (NTRS)

Kofal, Allen E.

1987-01-01

The purpose of this extension to the OTV Concept Definition and Systems Analysis Study was to improve the definition of the OTV Program that will be most beneficial to the nation in the 1995 to 2010 timeframe. The implications of the defined mission and defined launch vehicle are investigated. The key mission requirements identified for the Space Transportation Architecture Study (STAS) were established and reflect a need for early capability and more ambitious capability growth. The key technical objectives and related issues addressed are summarized. The analyses of selected areas including aerobrake design, proximity operations, and the balance of EVA and IVA operations used in the support of the OTV at the space-base were enhanced. Sensitivity studies were conducted to establish how the OTV program should be tailored to meet changing circumstances.

Identity, Institutions and Systemic Change: The Case of Higher Education in South Africa

ERIC Educational Resources Information Center

Ruth, Damian

2006-01-01

This article reports findings related to race, ethnicity and institutional type from a more extensive study on the perceptions of South African academics on academic workload. An attempt in a South African university department to distribute workload fairly indicated this task involved personal and sensitive concerns, which often had to do with…

Comparison between Surrogate Indexes of Insulin Sensitivity/Resistance and Hyperinsulinemic Euglycemic Glucose Clamps in Rhesus Monkeys

PubMed Central

Lee, Ho-Won; Muniyappa, Ranganath; Yan, Xu; Yue, Lilly Q.; Linden, Ellen H.; Chen, Hui; Hansen, Barbara C.

2011-01-01

The euglycemic glucose clamp is the reference method for assessing insulin sensitivity in humans and animals. However, clamps are ill-suited for large studies because of extensive requirements for cost, time, labor, and technical expertise. Simple surrogate indexes of insulin sensitivity/resistance including quantitative insulin-sensitivity check index (QUICKI) and homeostasis model assessment (HOMA) have been developed and validated in humans. However, validation studies of QUICKI and HOMA in both rats and mice suggest that differences in metabolic physiology between rodents and humans limit their value in rodents. Rhesus monkeys are a species more similar to humans than rodents. Therefore, in the present study, we evaluated data from 199 glucose clamp studies obtained from a large cohort of 86 monkeys with a broad range of insulin sensitivity. Data were used to evaluate simple surrogate indexes of insulin sensitivity/resistance (QUICKI, HOMA, Log HOMA, 1/HOMA, and 1/Fasting insulin) with respect to linear regression, predictive accuracy using a calibration model, and diagnostic performance using receiver operating characteristic. Most surrogates had modest linear correlations with SIClamp (r ≈ 0.4–0.64) with comparable correlation coefficients. Predictive accuracy determined by calibration model analysis demonstrated better predictive accuracy of QUICKI than HOMA and Log HOMA. Receiver operating characteristic analysis showed equivalent sensitivity and specificity of most surrogate indexes to detect insulin resistance. Thus, unlike in rodents but similar to humans, surrogate indexes of insulin sensitivity/resistance including QUICKI and log HOMA may be reasonable to use in large studies of rhesus monkeys where it may be impractical to conduct glucose clamp studies. PMID:21209021

The effects of negative emotions on sensory perception: fear but not anger decreases tactile sensitivity.

PubMed

Kelley, Nicholas J; Schmeichel, Brandon J

2014-01-01

Emotions and sensory perceptions are closely intertwined. Of the five senses, sight has been by far the most extensively studied sense in emotion research. Relatively less is known about how emotions influence the other four senses. Touch is essential for nonverbal communication in both humans and other animals. The current investigation tested competing hypotheses about the effect of fear on tactile perception. One hypothesis based on evolutionary considerations predicts that fear enhances sensory perception, including tactile sensitivity. A competing hypothesis based on research on peripheral psychophysiology predicts that fear should decrease tactile sensitivity. Two experiments that induced negative emotional states and measured two-point discrimination ability at the fingertip found that fear reduces tactile sensitivity relative to anger or a neutral control condition (Studies 1 and 2). These findings did not appear to be driven by participants' naïve beliefs about the influence of emotions on touch (Study 3). The results represent the first evidence of the causal impact of emotional states on tactile sensitivity, are consistent with prior evidence for the peripheral physiological effects of fear, and offer novel empirical grounds for developing and advancing theories of emotional influences on sensory perception.

The effects of negative emotions on sensory perception: fear but not anger decreases tactile sensitivity

PubMed Central

Kelley, Nicholas J.; Schmeichel, Brandon J.

2014-01-01

Emotions and sensory perceptions are closely intertwined. Of the five senses, sight has been by far the most extensively studied sense in emotion research. Relatively less is known about how emotions influence the other four senses. Touch is essential for nonverbal communication in both humans and other animals. The current investigation tested competing hypotheses about the effect of fear on tactile perception. One hypothesis based on evolutionary considerations predicts that fear enhances sensory perception, including tactile sensitivity. A competing hypothesis based on research on peripheral psychophysiology predicts that fear should decrease tactile sensitivity. Two experiments that induced negative emotional states and measured two-point discrimination ability at the fingertip found that fear reduces tactile sensitivity relative to anger or a neutral control condition (Studies 1 and 2). These findings did not appear to be driven by participants’ naïve beliefs about the influence of emotions on touch (Study 3). The results represent the first evidence of the causal impact of emotional states on tactile sensitivity, are consistent with prior evidence for the peripheral physiological effects of fear, and offer novel empirical grounds for developing and advancing theories of emotional influences on sensory perception. PMID:25202299

Air-borne and tissue-borne sensitivities of bioacoustic sensors used on the skin surface.

PubMed

Zañartu, Matías; Ho, Julio C; Kraman, Steve S; Pasterkamp, Hans; Huber, Jessica E; Wodicka, George R

2009-02-01

Measurements of body sounds on the skin surface have been widely used in the medical field and continue to be a topic of current research, ranging from the diagnosis of respiratory and cardiovascular diseases to the monitoring of voice dosimetry. These measurements are typically made using light-weight accelerometers and/or air-coupled microphones attached to the skin. Although normally neglected, air-borne sounds generated by the subject or other sources of background noise can easily corrupt such recordings, which is particularly critical in the recording of voiced sounds on the skin surface. In this study, the sensitivity of commonly used bioacoustic sensors to air-borne sounds was evaluated and compared with their sensitivity to tissue-borne body sounds. To delineate the sensitivity to each pathway, the sensors were first tested in vitro and then on human subjects. The results indicated that, in general, the air-borne sensitivity is sufficiently high to significantly corrupt body sound signals. In addition, the air-borne and tissue-borne sensitivities can be used to discriminate between these components. Although the study is focused on the evaluation of voiced sounds on the skin surface, an extension of the proposed methods to other bioacoustic applications is discussed.

Environmental ground borne noise and vibration protection of sensitive cultural receptors along the Athens Metro Extension to Piraeus.

PubMed

Vogiatzis, Konstantinos

2012-11-15

Attiko Metro S.A., the state company ensuring the development of the Athens Metro network, has recently initiated a new extension of 7.6 km, has planned for line 3 of Athens Metro from Haidari to Piraeus "Dimotikon Theatre" towards "University of Piraeus" (forestation), connecting the major Piraeus Port with "Eleftherios Venizelos" International Airport. The Piraeus extension consists of a Tunnel Boring Machine, 2 tracks and, tunnel sections, as well as 6 stations and a forestation (New Austrian Tunnelling Method) at the end of the alignment. In order to avoid the degradation of the urban acoustic environment from ground borne noise and vibration during metro operation, the assessment of the required track types and possible noise mitigation measures was executed, and for each section and each sensitive building, the ground borne noise and vibration levels will be numerically predicted. The calculated levels were then compared with ground borne noise and vibration level criteria. The necessary mitigation measures were defined in order to guarantee, in each location along the extension, the allowable ground borne Noise and Vibration max. levels inside nearby sensitive buildings taking into account alternative Transfer Functions for ground borne noise diffusion inside the buildings. Ground borne noise levels were proven to be higher than the criterion where special track work is present and also in the case of the sensitive receptor: "Dimotikon Theatre". In order to reduce the ground borne noise levels to allowable values in these sections, the installation of tracks and special track work on a floating slab was assessed and recommended. Copyright © 2012 Elsevier B.V. All rights reserved.

The Model Optimization, Uncertainty, and SEnsitivity analysis (MOUSE) toolbox: overview and application

USDA-ARS?s Scientific Manuscript database

For several decades, optimization and sensitivity/uncertainty analysis of environmental models has been the subject of extensive research. Although much progress has been made and sophisticated methods developed, the growing complexity of environmental models to represent real-world systems makes it...

Sensitivity analysis as an aid in modelling and control of (poorly-defined) ecological systems. [closed ecological systems

NASA Technical Reports Server (NTRS)

Hornberger, G. M.; Rastetter, E. B.

1982-01-01

A literature review of the use of sensitivity analyses in modelling nonlinear, ill-defined systems, such as ecological interactions is presented. Discussions of previous work, and a proposed scheme for generalized sensitivity analysis applicable to ill-defined systems are included. This scheme considers classes of mathematical models, problem-defining behavior, analysis procedures (especially the use of Monte-Carlo methods), sensitivity ranking of parameters, and extension to control system design.

6,7-dimethoxy-coumarin as a probe of hydration dynamics in biologically relevant systems

NASA Astrophysics Data System (ADS)

Ghose, Avisek; Amaro, Mariana; Kovaricek, Petr; Hof, Martin; Sykora, Jan

2018-04-01

Coumarin derivatives are well known fluorescence reporters for investigating biological systems due to their strong micro-environment sensitivity. Despite having wide range of environment sensitive fluorescence probes, the potential of 6,7-dimethoxy-coumarin has not been studied extensively so far. With a perspective of its use in protein studies, namely using the unnatural amino acid technology or as a substrate for hydrolase enzymes, we study acetyloxymethyl-6,7-dimethoxycoumarin (Ac-DMC). We investigate the photophysics and hydration dynamics of this dye in aerosol-OT (AOT) reverse micelles at various water contents using the time dependent fluorescence shift (TDFS) method. The TDFS response in AOT reverse micelles from water/surfactant ratio of 0 to 20 confirms its sensitivity towards the hydration and mobility of its microenvironment. Moreover, we show that the fluorophore can be efficiently quenched by halide ions. Hence, we conclude that the 6,7-dimethoxy-methylcoumarin fluorophore is useful for studying hydration parameters in biologically relevant systems.

The Role of Cleaning Products in Epidemic Allergic Contact Dermatitis to Methylchloroisothiazolinone/Methylisothiazolinone.

PubMed

Marrero-Alemán, Gabriel; Saavedra Santana, Pedro; Liuti, Federica; Hernández, Noelia; López-Jiménez, Esmeralda; Borrego, Leopoldo

Sensitivity to methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) has increased rapidly over recent years. This increase is mainly related to the extensive use of high concentrations of MI in cosmetic products, although a growing number of cases of occupational allergic contact dermatitis are caused by MCI/MI. The aim of this study was to examine the association between the increase in MCI/MI sensitization and the work performed by the patients in our area. A retrospective study was undertaken of the records of a total of 1179 patients who had undergone contact skin patch tests for MCI/MI from January 2005 to December 2015. A multivariate logistic regression analysis was performed to identify the factors independently associated with sensitivity to MCI/MI. A constant increase in MCI/MI sensitization was observed over the observation period. The only work associated with a significant increase in the prevalence of MCI/MI sensitization was cleaning, with 38.5% of the cleaning professionals with MCI/MI sensitization consulting for cosmetics-related dermatitis. Occupational sensitization to MCI/MI in cleaning professionals is worryingly increasing. This, in turn, could possibly account for many cases of cosmetics-associated contact dermatitis. Our findings suggest that a review of the regulations with regard to isothiazolinone concentrations in industrial and household detergents is necessary.

Approaches for assessing risks to sensitive populations: Lessons learned from evaluating risks in the pediatric populations*

EPA Science Inventory

Assessing the risk profiles of potentially sensitive populations requires a 'tool chest' of methodological approaches to adequately characterize and evaluate these populations. At present, there is an extensive body of literature on methodologies that apply to the evaluation of...

Overview and application of the Model Optimization, Uncertainty, and SEnsitivity Analysis (MOUSE) toolbox

USDA-ARS?s Scientific Manuscript database

For several decades, optimization and sensitivity/uncertainty analysis of environmental models has been the subject of extensive research. Although much progress has been made and sophisticated methods developed, the growing complexity of environmental models to represent real-world systems makes it...

SCALE Continuous-Energy Eigenvalue Sensitivity Coefficient Calculations

DOE PAGES

Perfetti, Christopher M.; Rearden, Bradley T.; Martin, William R.

2016-02-25

Sensitivity coefficients describe the fractional change in a system response that is induced by changes to system parameters and nuclear data. The Tools for Sensitivity and UNcertainty Analysis Methodology Implementation (TSUNAMI) code within the SCALE code system makes use of eigenvalue sensitivity coefficients for an extensive number of criticality safety applications, including quantifying the data-induced uncertainty in the eigenvalue of critical systems, assessing the neutronic similarity between different critical systems, and guiding nuclear data adjustment studies. The need to model geometrically complex systems with improved fidelity and the desire to extend TSUNAMI analysis to advanced applications has motivated the developmentmore » of a methodology for calculating sensitivity coefficients in continuous-energy (CE) Monte Carlo applications. The Contributon-Linked eigenvalue sensitivity/Uncertainty estimation via Tracklength importance CHaracterization (CLUTCH) and Iterated Fission Probability (IFP) eigenvalue sensitivity methods were recently implemented in the CE-KENO framework of the SCALE code system to enable TSUNAMI-3D to perform eigenvalue sensitivity calculations using continuous-energy Monte Carlo methods. This work provides a detailed description of the theory behind the CLUTCH method and describes in detail its implementation. This work explores the improvements in eigenvalue sensitivity coefficient accuracy that can be gained through the use of continuous-energy sensitivity methods and also compares several sensitivity methods in terms of computational efficiency and memory requirements.« less

Inhibition of the spider heartbeat by gravity and vibration

NASA Technical Reports Server (NTRS)

Finck, A.

1984-01-01

The rate and vigor of the spider heartbeat is controlled by an external pacemaker. A mechanical feature of the spider cardio-vascular system is the production of high serum pressure in the prosoma and the legs. This appears to be the source for leg extension. The lyriform organ on the patella of the leg is sensitive to vibratory and kinesthetic stimuli. This sensitivity depends upon the degree of leg extension. Thus the activity of the heart and the response characteristics of the sense receptor are related. The effect of a supra-threshold vibratory or gravitational stimulus is to produce an inhibition and a tachycardia of the spider heartbeat.

"Signal-on" photoelectrochemical biosensor for sensitive detection of human T-Cell lymphotropic virus type II DNA: dual signal amplification strategy integrating enzymatic amplification with terminal deoxynucleotidyl transferase-mediated extension.

PubMed

Shen, Qingming; Han, Li; Fan, Gaochao; Zhang, Jian-Rong; Jiang, Liping; Zhu, Jun-Jie

2015-01-01

A novel "signal-on" photoelectrochemical (PEC) biosensor for sensitive detection of human T-cell lymphotropic virus type II (HTLV-II) DNA was developed on the basis of enzymatic amplification coupled with terminal deoxynucleotidyl transferase (TdT)-mediated extension strategy. The intensity of the photocurrent signal was proportional to the concentration of the HTLV-II DNA-target DNA (tDNA) by dual signal amplification. In this protocol, GR-CdS:Mn/ZnS nanocomposites were used as photoelectric conversion material, while pDNA was used as the tDNA recognizing unit. Moreover, the TdT-mediated extension and the enzymatic signal amplification technique were used to enhance the sensitivity of detection. Using this novel dual signal amplification strategy, the prototype of PEC DNA sensor can detect as low as ∼0.033 fM of HTLV-II DNA with a linear range of 0.1-5000 fM, with excellent differentiation ability even for single-base mismatches. This PEC DNA assay opens a promising platform to detect various DNA targets at ultralow levels for early diagnoses of different diseases.

The distribution of RNA polymerase in Escherichia coli is dynamic and sensitive to environmental cues | Center for Cancer Research

Cancer.gov

Despite extensive genetic, biochemical and structural studies on Escherichia coli RNA polymerase (RNAP), little is known about its location and distribution in response to environmental changes. To visualize the RNAP by fluorescence microscopy in E. coli under different physiological conditions, we constructed a functional rpoC-gfp gene fusion on the chromosome.

Predicting extracapsular involvement in prostate cancer through the tumor contact length and the apparent diffusion coefficient.

PubMed

Granja, M F; Pedraza, C M; Flórez, D C; Romero, J A; Palau, M A; Aguirre, D A

To evaluate the diagnostic performance of the length of the tumor contact with the capsule (LTC) and the apparent diffusion coefficient (ADC) map in the prediction of microscopic extracapsular extension in patients with prostate cancer who are candidates for radical prostatectomy. We used receiver operating curves to retrospectively study the diagnostic performance of the ADC map and the LTC as predictors of microscopic extracapsular extension in 92 patients with prostate cancer and moderate to high risk who were examined between May 2011 and December 2013. The optimal cutoff for the ADC map was 0.87× 10 -3 mm 2 /s, which yielded an area under the ROC curve of 72% (95% CI: 57%-86%), corresponding to a sensitivity of 83% and a specificity of 61%. The optimal cutoff for the LTC was 17.5mm, which yielded an area under the ROC curve of 74% (95% CI: 61%-87%), corresponding to a sensitivity of 91% and a specificity of 57%. Combining the two criteria improved the diagnostic performance, yielding an area under the ROC curve of 77% (95% CI: 62%-92%), corresponding to a sensitivity of 77% and a specificity of 61%. We elaborated a logistic regression model, obtaining an area under the ROC curve of 82% (95% CI: 73%-93%). Using quantitative measures improves the diagnostic accuracy of multiparametric magnetic resonance imaging in the staging of prostate cancer. The values of the ADC and LTC were predictors of microscopic extracapsular extension, and the best results were obtained when both values were used in combination. Copyright © 2017 SERAM. Publicado por Elsevier España, S.L.U. All rights reserved.

Central Sensitization-Based Classification for Temporomandibular Disorders: A Pathogenetic Hypothesis

PubMed Central

Cattaneo, Ruggero; Marci, Maria Chiara; Pietropaoli, Davide; Ortu, Eleonora

2017-01-01

Dysregulation of Autonomic Nervous System (ANS) and central pain pathways in temporomandibular disorders (TMD) is a growing evidence. Authors include some forms of TMD among central sensitization syndromes (CSS), a group of pathologies characterized by central morphofunctional alterations. Central Sensitization Inventory (CSI) is useful for clinical diagnosis. Clinical examination and CSI cannot identify the central site(s) affected in these diseases. Ultralow frequency transcutaneous electrical nerve stimulation (ULFTENS) is extensively used in TMD and in dental clinical practice, because of its effects on descending pain modulation pathways. The Diagnostic Criteria for TMD (DC/TMD) are the most accurate tool for diagnosis and classification of TMD. However, it includes CSI to investigate central aspects of TMD. Preliminary data on sensory ULFTENS show it is a reliable tool for the study of central and autonomic pathways in TMD. An alternative classification based on the presence of Central Sensitization and on individual response to sensory ULFTENS is proposed. TMD may be classified into 4 groups: (a) TMD with Central Sensitization ULFTENS Responders; (b) TMD with Central Sensitization ULFTENS Nonresponders; (c) TMD without Central Sensitization ULFTENS Responders; (d) TMD without Central Sensitization ULFTENS Nonresponders. This pathogenic classification of TMD may help to differentiate therapy and aetiology. PMID:28932132

The Ability to Diagnose Intrahepatic Cholangiocarcinoma Definitively Using Novel Branched DNA-Enhanced Albumin RNA In Situ Hybridization Technology.

PubMed

Ferrone, Cristina R; Ting, David T; Shahid, Mohammed; Konstantinidis, Ioannis T; Sabbatino, Francesco; Goyal, Lipika; Rice-Stitt, Travis; Mubeen, Ayesha; Arora, Kshitij; Bardeesey, Nabeel; Miura, John; Gamblin, T Clark; Zhu, Andrew X; Borger, Darrell; Lillemoe, Keith D; Rivera, Miguel N; Deshpande, Vikram

2016-01-01

Intrahepatic cholangiocarcinoma (ICC) often is a diagnosis determined by exclusion. Distinguishing ICC from other metastatic adenocarcinomas based on histopathologic or immunohistochemical analysis often is difficult and requires an extensive workup. This study aimed to determine whether albumin, whose expression is restricted to the liver, has potential as a biomarker for ICC using a novel and highly sensitive RNA in situ hybridization (ISH) platform. Modified branched DNA probes were developed for albumin RNA ISH. The study evaluated 467 patient samples of primary and metastatic lesions. Of the 467 samples evaluated, 83 were ICCs, 42 were hepatocellular carcinomas (HCCs), and 332 were nonhepatic carcinomas including tumors arising from the perihilar region and bile duct, pancreas, stomach, esophagus, colon, breast, ovary, endometrium, kidney, and urinary bladder. Albumin RNA ISH was highly sensitive for cancers of liver origin, staining positive in 82 (99 %) of 83 ICCs and in 42 HCCs (100 %). Perihilar and distal bile duct carcinomas as well as carcinomas arising at other sites tested negative for albumin. Notably, 6 (22 %) of 27 intrahepatic tumors previously diagnosed as carcinomas of undetermined origin tested positive for albumin. Albumin RNA ISH is a sensitive and highly specific diagnostic tool for distinguishing ICC from metastatic adenocarcinoma to the liver or carcinoma of unknown origin. Albumin RNA ISH could replace the extensive diagnostic workup, leading to timely confirmation of the ICC diagnosis. Additionally, the assay could serve as a guide to distinguish ICC from perihilar adenocarcinoma.

Approaches for Assessing Risks to Sensitive Populations: Lessons Learned from Evaluating Risks in the Pediatric Population

EPA Science Inventory

Assessing the risk profiles of potentially sensitive populations requires a "tool chest" of methodological approaches to adequately characterize and evaluate these populations. At present, there is an extensive body of literature on methodologies that apply to the evaluation of t...

Molecular mimicry between cockroach and helminth glutathione S-transferases promotes cross-reactivity and cross-sensitization

USDA-ARS?s Scientific Manuscript database

The extensive similarities between helminth proteins and allergens are thought to contribute to helminth-driven allergic sensitization. We investigated the molecular and structural similarities between Bla g 5, a major glutathione-S transferase (GST) allergen of cockroaches, and the GST of Wucherer...

A contaminant-free assessment of Endogenous Retroviral RNA in human plasma

PubMed Central

Karamitros, Timokratis; Paraskevis, Dimitrios; Hatzakis, Angelos; Psichogiou, Mina; Elefsiniotis, Ioannis; Hurst, Tara; Geretti, Anna-Maria; Beloukas, Apostolos; Frater, John; Klenerman, Paul; Katzourakis, Aris; Magiorkinis, Gkikas

2016-01-01

Endogenous retroviruses (ERVs) comprise 6–8% of the human genome. HERVs are silenced in most normal tissues, up-regulated in stem cells and in placenta but also in cancer and HIV-1 infection. Crucially, there are conflicting reports on detecting HERV RNA in non-cellular clinical samples such as plasma that suggest the study of HERV RNA can be daunting. Indeed, we find that the use of real-time PCR in a quality assured clinical laboratory setting can be sensitive to low-level proviral contamination. We developed a mathematical model for low-level contamination that allowed us to design a laboratory protocol and standard operating procedures for robust measurement of HERV RNA. We focus on one family, HERV-K HML-2 (HK2) that has been most recently active even though they invaded our ancestral genomes almost 30 millions ago. We extensively validated our experimental design on a model cell culture system showing high sensitivity and specificity, totally eliminating the proviral contamination. We then tested 236 plasma samples from patients infected with HIV-1, HCV or HBV and found them to be negative. The study of HERV RNA for human translational studies should be performed with extensively validated protocols and standard operating procedures to control the widespread low-level human DNA contamination. PMID:27640347

Detection of high-risk mucosal human papillomavirus DNA in human specimens by a novel and sensitive multiplex PCR method combined with DNA microarray.

PubMed

Gheit, Tarik; Tommasino, Massimo

2011-01-01

Epidemiological and functional studies have clearly demonstrated that certain types of human papillomavirus (HPV) from the genus alpha of the HPV phylogenetic tree, referred to as high-risk (HR) types, are the etiological cause of cervical cancer. Several methods for HPV detection and typing have been developed, and their importance in clinical and epidemiological studies has been well demonstrated. However, comparative studies have shown that several assays have different sensitivities for the detection of specific HPV types, particularly in the case of multiple infections. In this chapter, we describe a novel one-shot method for the detection and typing of 19 mucosal HR HPV types (types 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73, and 82). The assay combines the advantages of the multiplex PCR methods, i.e., high sensitivity and the possibility to perform multiple amplifications in a single reaction, with an array primer extension (APEX) assay. The latter method offers the benefits of Sanger dideoxy sequencing with the high-throughput potential of the microarray. Initial studies have revealed that the assay is very sensitive in detecting multiple HPV infections.

Rapid, sensitive and direct analysis of exopolysaccharides from biofilm on aluminum surfaces exposed to sea water using MALDI-TOF MS.

PubMed

Hasan, Nazim; Gopal, Judy; Wu, Hui-Fen

2011-11-01

Biofilm studies have extensive significance since their results can provide insights into the behavior of bacteria on material surfaces when exposed to natural water. This is the first attempt of using matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) for detecting the polysaccharides formed in a complex biofilm consisting of a mixed consortium of marine microbes. MALDI-MS has been applied to directly analyze exopolysaccharides (EPS) in the biofilm formed on aluminum surfaces exposed to seawater. The optimal conditions for MALDI-MS applied to EPS analysis of biofilm have been described. In addition, microbiologically influenced corrosion of aluminum exposed to sea water by a marine fungus was also observed and the fungus identity established using MALDI-MS analysis of EPS. Rapid, sensitive and direct MALDI-MS analysis on biofilm would dramatically speed up and provide new insights into biofilm studies due to its excellent advantages such as simplicity, high sensitivity, high selectivity and high speed. This study introduces a novel, fast, sensitive and selective platform for biofilm study from natural water without the need of tedious culturing steps or complicated sample pretreatment procedures. Copyright © 2011 John Wiley & Sons, Ltd.

Increasing accuracy in the interval analysis by the improved format of interval extension based on the first order Taylor series

NASA Astrophysics Data System (ADS)

Li, Yi; Xu, Yan Long

2018-05-01

When the dependence of the function on uncertain variables is non-monotonic in interval, the interval of function obtained by the classic interval extension based on the first order Taylor series will exhibit significant errors. In order to reduce theses errors, the improved format of the interval extension with the first order Taylor series is developed here considering the monotonicity of function. Two typical mathematic examples are given to illustrate this methodology. The vibration of a beam with lumped masses is studied to demonstrate the usefulness of this method in the practical application, and the necessary input data of which are only the function value at the central point of interval, sensitivity and deviation of function. The results of above examples show that the interval of function from the method developed by this paper is more accurate than the ones obtained by the classic method.

Interaction of growth hormone receptor/binding protein gene disruption and caloric restriction for insulin sensitivity and attenuated aging

PubMed Central

Arum, Oge; Saleh, Jamal; Boparai, Ravneet; Turner, Jeremy; Kopchick, John; Khardori, Romesh; Bartke, Andrzej

2014-01-01

The correlation of physiological sensitivity to insulin ( vis-à-vis glycemic regulation) and longevity is extensively established, creating a justifiable gerontological interest on whether insulin sensitivity is causative, or even predictive, of some or all phenotypes of slowed senescence (including longevity). The growth hormone receptor/ binding protein gene-disrupted (GHR-KO) mouse is the most extensively investigated insulin-sensitive, attenuated aging model. It was reported that, in a manner divergent from similar mutants, GHR-KO mice fail to respond to caloric restriction (CR) by altering their insulin sensitivity. We hypothesized that maximized insulin responsiveness is what causes GHR-KO mice to exhibit a suppressed survivorship response to dietary (including caloric) restriction; and attempted to refute this hypothesis by assessing the effects of CR on GHR-KO mice for varied slow-aging-associated phenotypes. In contrast to previous reports, we found GHR-KO mice on CR to be less responsive than their ad libitum (A.L.) counterparts to the hypoglycemia-inducing effects of insulin. Further, CR had negligible effects on the metabolism or cognition of GHR-KO mice. Therefore, our data suggest that the effects of CR on the insulin sensitivity of GHR-KO mice do not concur with the effects of CR on the aging of GHR-KO mice. PMID:25789159

Aircraft scatterometer observations of soil moisture on rangeland watersheds

NASA Technical Reports Server (NTRS)

Jackson, T. J.; Oneill, P. E.

1983-01-01

Extensive studies conducted by several researchers using truck-mounted active microwave sensors have shown the sensitivity of these sensors to soil moisture variations. The logical extension of these results is the evaluation of similar systems at lower resolutions typical of operational systems. Data collected during a series of aircraft flights in 1978 and 1980 over four rangeland watersheds located near Chickasha, Oklahoma, were analyzed in this study. These data included scatterometer measurements made at 1.6 and 4.75 GHz using a NASA aircraft and ground observations of soil moisture for a wide range of moisture conditions. Data were analyzed for consistency and compared to previous truck and aircraft results. Results indicate that the sensor system is capable of providing consistent estimates of soil moisture under the conditions tested.

An optimal search filter for retrieving systematic reviews and meta-analyses

PubMed Central

2012-01-01

Background Health-evidence.ca is an online registry of systematic reviews evaluating the effectiveness of public health interventions. Extensive searching of bibliographic databases is required to keep the registry up to date. However, search filters have been developed to assist in searching the extensive amount of published literature indexed. Search filters can be designed to find literature related to a certain subject (i.e. content-specific filter) or particular study designs (i.e. methodological filter). The objective of this paper is to describe the development and validation of the health-evidence.ca Systematic Review search filter and to compare its performance to other available systematic review filters. Methods This analysis of search filters was conducted in MEDLINE, EMBASE, and CINAHL. The performance of thirty-one search filters in total was assessed. A validation data set of 219 articles indexed between January 2004 and December 2005 was used to evaluate performance on sensitivity, specificity, precision and the number needed to read for each filter. Results Nineteen of 31 search filters were effective in retrieving a high level of relevant articles (sensitivity scores greater than 85%). The majority achieved a high degree of sensitivity at the expense of precision and yielded large result sets. The main advantage of the health-evidence.ca Systematic Review search filter in comparison to the other filters was that it maintained the same level of sensitivity while reducing the number of articles that needed to be screened. Conclusions The health-evidence.ca Systematic Review search filter is a useful tool for identifying published systematic reviews, with further screening to identify those evaluating the effectiveness of public health interventions. The filter that narrows the focus saves considerable time and resources during updates of this online resource, without sacrificing sensitivity. PMID:22512835

Novel method for detecting the hadronic component of extensive air showers

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

Gromushkin, D. M., E-mail: DMGromushkin@mephi.ru; Volchenko, V. I.; Petrukhin, A. A.

2015-05-15

A novel method for studying the hadronic component of extensive air showers (EAS) is proposed. The method is based on recording thermal neutrons accompanying EAS with en-detectors that are sensitive to two EAS components: an electromagnetic (e) component and a hadron component in the form of neutrons (n). In contrast to hadron calorimeters used in some arrays, the proposed method makes it possible to record the hadronic component over the whole area of the array. The efficiency of a prototype array that consists of 32 en-detectors was tested for a long time, and some parameters of the neutron EAS componentmore » were determined.« less

Fatigue reassessment for lifetime extension of offshore wind monopile substructures

NASA Astrophysics Data System (ADS)

Ziegler, Lisa; Muskulus, Michael

2016-09-01

Fatigue reassessment is required to decide about lifetime extension of aging offshore wind farms. This paper presents a methodology to identify important parameters to monitor during the operational phase of offshore wind turbines. An elementary effects method is applied to analyze the global sensitivity of residual fatigue lifetimes to environmental, structural and operational parameters. Therefore, renewed lifetime simulations are performed for a case study which consists of a 5 MW turbine with monopile substructure in 20 m water depth. Results show that corrosion, turbine availability, and turbulence intensity are the most influential parameters. This can vary strongly for other settings (water depth, turbine size, etc.) making case-specific assessments necessary.

Retinohypothalamic connections in the rhesus monkey

NASA Astrophysics Data System (ADS)

Chijuka, John C.

Previous studies of retinohypothalamic projections in macaques were performed with anterograde degeneration or autoradiographic techniques that were not sufficiently sensitive to fully define these projections. Results of studies in non-primates using sensitive tracers have revealed more extensive retinohypothalamic projection than previously seen. We hypothesize that there are more extensive retinohypothalamic projections in the higher primate, macaque monkey. Thus, the primary goal of this investigation was to characterize the retinohypothalamic projections in the macaque monkey using the more sensitive tract tracer, cholera toxin subunit B (CTB) unilaterally injected intravitreally. Secondary goals were to determine: (1) whether there is a retinal projection to the sleep-related ventrolateral preoptic area of the hypothalamus; (2) whether there are direct retinal projections to gonadotropin-releasing hormone neurons in the hypothalamus; and (3) whether any retinally-projecting hypothalamic neurons can be retrogradely labeled by intravitreal CTB injections. Our results confirmed our hypothesis that there are more extensive projections to the central targets. We found that, in addition to the well-described retinal projection to the suprachiasmatic nucleus, a number of other hypothalamic areas were labeled. We observed projections to the medial and lateral preoptic areas, including the sleep-related ventrolateral preoptic area. A number of retinal fibers terminated immediately dorsal to the supraoptic nucleus (SO), with a few fibers penetrating and terminating within the nucleus. A few fibers continued laterally beyond the SO into the substantia innominata immediately ventral to the nucleus basalis of Meynert. In addition, a dense plexus of CTB-labeled, retinal fibers were present in the subventricular nucleus and adjacent subventricular area. Some of these fibers coursed dorsally from this region to penetrate the ependyma lining the third ventricle and apparently contacted the cerebrospinal fluid (CSF). We also observed projections to the anterior hypothalamic area throughout its rostrocaudal extent and to the posterior region of the lateral preoptic area immediately dorsal to the supraoptic nucleus. More posteriorly, fibers projected to the arcuate/infundibular region, and a few fibers could be seen to course towards the paraventricular, parvicellular region and posterior hypothalamic region close to the third ventricle. Finally, some retrogradely-labeled neurons were present in most injected cases. Overall, these results show that retinohypothalamic projections in the macaque are more extensive than once thought, and presumably play more roles than solely entraining the suprachiasmatic nucleus, the central circadian controller. (Abstract shortened by UMI.)

Extension lifetime for dye-sensitized solar cells through multiple dye adsorption/desorption process

NASA Astrophysics Data System (ADS)

Chiang, Yi-Fang; Chen, Ruei-Tang; Shen, Po-Shen; Chen, Peter; Guo, Tzung-Fang

2013-03-01

In this study, we propose a novel concept of extending the lifetime of dye-sensitized solar cells (DSCs) and reducing the costs of re-conditioning DSCs by recycling the FTO/TiO2 substrates. The photovoltaic performances of DSCs using substrates with various cycles of dye uptake and rinse off history are tested. The results show that dye adsorption and Voc are significantly increased under multiple dye adsorption/desorption process and resulted in the improvement of power conversion efficiency. Moreover, the dyeing kinetics is faster after multiple recycling processes, which is favorable for the industrial application. With surface analysis and charge transport characteristics, we also demonstrate the optimal functionality of TiO2/dye interface for the improved Voc and efficiency. The results confirm that the improved performances are due to increased dye loading and dense packing of dye molecules. Our results are beneficial for the understanding on the extension of DSCs lifetime after long-term operation in the application of DSC modules. This approach may also be applied in the replacement of newly synthesized photosensitizes to the active cells.

Quantifying differences in responses of aquatic insects to trace metal exposure in field studies and short-term stream mesocosm experiments

USGS Publications Warehouse

Iwasaki, Yuichi; Schmidt, Travis S.; Clements, William H.

2018-01-01

Characterizing macroinvertebrate taxa as either sensitive or tolerant is of critical importance for investigating impacts of anthropogenic stressors in aquatic ecosystems and for inferring causality. However, our understanding of relative sensitivity of aquatic insects to metals in the field and under controlled conditions in the laboratory or mesocosm experiments is limited. In this study, we compared the response of 16 lotic macroinvertebrate families to metals in short-term (10-day) stream mesocosm experiments and in a spatially extensive field study of 154 Colorado streams. Comparisons of field and mesocosm-derived EC20 (effect concentration of 20%) values showed that aquatic insects were generally more sensitive to metals in the field. Although the ranked sensitivity to metals was similar for many families, we observed large differences between field and mesocosm responses for some groups (e.g., Baetidae and Heptageniidae). These differences most likely resulted from the inability of short-term experiments to account for factors such as dietary exposure to metals, rapid recolonization in the field, and effects of metals on sensitive life stages. Understanding mechanisms responsible for differences among field, mesocosm, and laboratory approaches would improve our ability to predict contaminant effects and establish ecologically meaningful water-quality criteria.

Model to Test Electric Field Comparisons in a Composite Fairing Cavity

NASA Technical Reports Server (NTRS)

Trout, Dawn; Burford, Janessa

2012-01-01

Evaluating the impact of radio frequency transmission in vehicle fairings is important to sensitive spacecraft. This study shows cumulative distribution function (CDF) comparisons of composite . a fairing electromagnetic field data obtained by computational electromagnetic 3D full wave modeling and laboratory testing. This work is an extension of the bare aluminum fairing perfect electric conductor (PEC) model. Test and model data correlation is shown.

Model to Test Electric Field Comparisons in a Composite Fairing Cavity

NASA Technical Reports Server (NTRS)

Trout, Dawn H.; Burford, Janessa

2013-01-01

Evaluating the impact of radio frequency transmission in vehicle fairings is important to sensitive spacecraft. This study shows cumulative distribution function (CDF) comparisons of composite a fairing electromagnetic field data obtained by computational electromagnetic 3D full wave modeling and laboratory testing. This work is an extension of the bare aluminum fairing perfect electric conductor (PEC) model. Test and model data correlation is shown.

Diagnosing ASD in Adults without ID: Accuracy of the ADOS-2 and the ADI-R

ERIC Educational Resources Information Center

Fusar-Poli, Laura; Brondino, Natascia; Rocchetti, Matteo; Panisi, Cristina; Provenzani, Umberto; Damiani, Stefano; Politi, Pierluigi

2017-01-01

Diagnosing autism spectrum disorder (ASD) in adulthood often represents a challenge in clinical practice. The aim of the present study was to evaluate the sensitivity and specificity of the ADOS and ADI-R in diagnosing ASD in adults. 113 subjects with an IQ of 70 or above were assessed through an extensive clinical evaluation. The ADOS-2 Module 4…

GLSENS: A Generalized Extension of LSENS Including Global Reactions and Added Sensitivity Analysis for the Perfectly Stirred Reactor

NASA Technical Reports Server (NTRS)

Bittker, David A.

1996-01-01

A generalized version of the NASA Lewis general kinetics code, LSENS, is described. The new code allows the use of global reactions as well as molecular processes in a chemical mechanism. The code also incorporates the capability of performing sensitivity analysis calculations for a perfectly stirred reactor rapidly and conveniently at the same time that the main kinetics calculations are being done. The GLSENS code has been extensively tested and has been found to be accurate and efficient. Nine example problems are presented and complete user instructions are given for the new capabilities. This report is to be used in conjunction with the documentation for the original LSENS code.

Controlled categorisation processing in brand extension evaluation by Indo-European language speakers. An ERP study.

PubMed

Fudali-Czyż, Agnieszka; Ratomska, Marta; Cudo, Andrzej; Francuz, Piotr; Kopiś, Natalia; Tużnik, Przemysław

2016-08-15

The purpose of our experiment was to test event-related potentials (ERP) accompanying the process of brand extension evaluation in people speaking Indo-European languages. The experimental procedure consisted of sequential presentations of pairs of stimuli; namely, a beverage brand name and a product name. The products fell into the category of beverages (congruent trials) or clothes (incongruent trials). In the response condition (RC), the participants decided whether they accepted the product as an extension of the brand. In the no-response condition (NRC), the participants' task was to attend the stimuli and try to remember them. In the response condition, the amplitudes of the N270, P300 and N400 components were sensitive to incongruence between the product category and the previously presented brand. However, in the no-response condition, differences emerged only at the level of early P1 and P2 components. Our results suggest that, in people speaking one of the Indo-European languages, the process of categorisation in brand extension evaluation is not automatic. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Community Concerns and Extension Youth Programs. Proceedings Regional Conference (February 18-20, 1981). Publication 28.

ERIC Educational Resources Information Center

White, Leigh Cree, Ed.

The 4-H/Community Resource Development workshop was designed to help people conducting Extension 4-H programs on sensitive and complex community issues improve their ability to create a better climate for discussion of alternatives and development of community projects. Topics of the presentations included the role of the 4-H administrator,…

Identification of Novel Glycosyltransferases Required for Assembly of the Pasteurella multocida A:1 Lipopolysaccharide and Their Involvement in Virulence▿ †

PubMed Central

Boyce, John D.; Harper, Marina; St. Michael, Frank; John, Marietta; Aubry, Annie; Parnas, Henrietta; Logan, Susan M.; Wilkie, Ian W.; Ford, Mark; Cox, Andrew D.; Adler, Ben

2009-01-01

We previously determined the structure of the Pasteurella multocida Heddleston type 1 lipopolysaccharide (LPS) molecule and characterized some of the transferases essential for LPS biosynthesis. We also showed that P. multocida strains expressing truncated LPS display reduced virulence. Here, we have identified all of the remaining glycosyltransferases required for synthesis of the oligosaccharide extension of the P. multocida Heddleston type 1 LPS, including a novel α-1,6 glucosyltransferase, a β-1,4 glucosyltransferase, a putative bifunctional galactosyltransferase, and two heptosyltransferases. In addition, we identified a novel oligosaccharide extension expressed only in a heptosyltransferase (hptE) mutant background. All of the analyzed mutants expressing LPS with a truncated main oligosaccharide extension displayed reduced virulence, but those expressing LPS with an intact heptose side chain were able to persist for long periods in muscle tissue. The hptC mutant, which expressed LPS with the shortest oligosaccharide extension and no heptose side chain, was unable to persist on the muscle or cause any disease. Furthermore, all of the mutants displayed increased sensitivity to the chicken antimicrobial peptide fowlicidin 1, with mutants expressing highly truncated LPS being the most sensitive. PMID:19168738

A service life extension (SLEP) approach to operating aging aircraft beyond their original design lives

NASA Astrophysics Data System (ADS)

Pentz, Alan Carter

With today's uncertain funding climate (including sequestration and continuing budget resolutions), decision makers face severe budgetary challenges to maintain dominance through all aspects of the Department of Defense (DoD). To meet war-fighting capabilities, the DoD continues to extend aircraft programs beyond their design service lives by up to ten years, and occasionally much more. The budget requires a new approach to traditional extension strategies (i.e., reuse, reset, and reclamation) for structural hardware. While extending service life without careful controls can present a safety concern, future operations planning does not consider how much risk is present when operating within sound structural principles. Traditional structural hardware extension methods drive increased costs. Decision makers often overlook the inherent damage tolerance and fatigue capability of structural components and rely on simple time- and flight-based cycle accumulation when determining aircraft retirement lives. This study demonstrates that decision makers should consider risk in addition to the current extension strategies. Through an evaluation of eight military aircraft programs and the application and simulation of F-18 turbine engine usage data, this dissertation shows that insight into actual aircraft mission data, consideration of fatigue capability, and service extension length are key factors to consider. Aircraft structural components, as well as many critical safety components and system designs, have a predefined level of conservatism and inherent damage tolerance. The methods applied in this study would apply to extensions of other critical structures such as bridges. Understanding how much damage tolerance is built into the design compared to the original design usage requirements presents the opportunity to manage systems based on risk. The study presents the sensitivity of these factors and recommends avenues for further research.

Scoping and sensitivity analyses for the Demonstration Tokamak Hybrid Reactor (DTHR)

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

Sink, D.A.; Gibson, G.

1979-03-01

The results of an extensive set of parametric studies are presented which provide analytical data of the effects of various tokamak parameters on the performance and cost of the DTHR (Demonstration Tokamak Hybrid Reactor). The studies were centered on a point design which is described in detail. Variations in the device size, neutron wall loading, and plasma aspect ratio are presented, and the effects on direct hardware costs, fissile fuel production (breeding), fusion power production, electrical power consumption, and thermal power production are shown graphically. The studies considered both ignition and beam-driven operations of DTHR and yielded results based onmore » two empirical scaling laws presently used in reactor studies. Sensitivity studies were also made for variations in the following key parameters: the plasma elongation, the minor radius, the TF coil peak field, the neutral beam injection power, and the Z/sub eff/ of the plasma.« less

CFD Simulation On The Pressure Distribution For An Isolated Single-Story House With Extension: Grid Sensitivity Analysis

NASA Astrophysics Data System (ADS)

Yahya, W. N. W.; Zaini, S. S.; Ismail, M. A.; Majid, T. A.; Deraman, S. N. C.; Abdullah, J.

2018-04-01

Damage due to wind-related disasters is increasing due to global climate change. Many studies have been conducted to study the wind effect surrounding low-rise building using wind tunnel tests or numerical simulations. The use of numerical simulation is relatively cheap but requires very good command in handling the software, acquiring the correct input parameters and obtaining the optimum grid or mesh. However, before a study can be conducted, a grid sensitivity test must be conducted to get a suitable cell number for the final to ensure an accurate result with lesser computing time. This study demonstrates the numerical procedures for conducting a grid sensitivity analysis using five models with different grid schemes. The pressure coefficients (CP) were observed along the wall and roof profile and compared between the models. The results showed that medium grid scheme can be used and able to produce high accuracy results compared to finer grid scheme as the difference in terms of the CP values was found to be insignificant.

Use of SCALE Continuous-Energy Monte Carlo Tools for Eigenvalue Sensitivity Coefficient Calculations

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

Perfetti, Christopher M; Rearden, Bradley T

2013-01-01

The TSUNAMI code within the SCALE code system makes use of eigenvalue sensitivity coefficients for an extensive number of criticality safety applications, such as quantifying the data-induced uncertainty in the eigenvalue of critical systems, assessing the neutronic similarity between different critical systems, and guiding nuclear data adjustment studies. The need to model geometrically complex systems with improved fidelity and the desire to extend TSUNAMI analysis to advanced applications has motivated the development of a methodology for calculating sensitivity coefficients in continuous-energy (CE) Monte Carlo applications. The CLUTCH and Iterated Fission Probability (IFP) eigenvalue sensitivity methods were recently implemented in themore » CE KENO framework to generate the capability for TSUNAMI-3D to perform eigenvalue sensitivity calculations in continuous-energy applications. This work explores the improvements in accuracy that can be gained in eigenvalue and eigenvalue sensitivity calculations through the use of the SCALE CE KENO and CE TSUNAMI continuous-energy Monte Carlo tools as compared to multigroup tools. The CE KENO and CE TSUNAMI tools were used to analyze two difficult models of critical benchmarks, and produced eigenvalue and eigenvalue sensitivity coefficient results that showed a marked improvement in accuracy. The CLUTCH sensitivity method in particular excelled in terms of efficiency and computational memory requirements.« less

Autocatalytic Patterning with Silver Using Tin(II) Chloride Sensitizer

ERIC Educational Resources Information Center

Mbindyo, Jeremiah K. N.; Anna, Laura J.; Fell, B. Andrew; Patton, David A.

2011-01-01

A silver mirror can be deposited on many types of surfaces from the reduction of the silver-diammine complex by a reducing sugar as proposed by Kemp in this "Journal". Three extensions of Kemp's demonstration that highlight the role of SnCl[subscript 2] sensitizer in the deposition of a silver mirror on surfaces are presented. The demonstration…

Flexural waves induced by electro-impulse deicing forces

NASA Technical Reports Server (NTRS)

Gien, P. H.

1990-01-01

The generation, reflection and propagation of flexural waves created by electroimpulsive deicing forces are demonstrated both experimentally and analytically in a thin circular plate and a thin semicylindrical shell. Analytical prediction of these waves with finite element models shows good correlation with acceleration and displacement measurements at discrete points on the structures studied. However, sensitivity to spurious flexural waves resulting from the spatial discretization of the structures is shown to be significant. Consideration is also given to composite structures as an extension of these studies.

6-OHDA induced calcium influx through N-type calcium channel alters membrane properties via PKA pathway in substantia nigra pars compacta dopaminergic neurons.

PubMed

Qu, Liang; Wang, Yuan; Zhang, Hai-Tao; Li, Nan; Wang, Qiang; Yang, Qian; Gao, Guo-Dong; Wang, Xue-Lian

2014-07-11

Voltage gated calcium channels (VGCC) are sensitive to oxidative stress, and their activation or inactivation can impact cell death. Although these channels have been extensively studied in expression systems, their role in the brain, particularly in the substantia nigra pars compacta (SNc), remain controversial. In this study, we assessed 6-hydroxydopamine (6-OHDA) induced transformation of firing pattern and functional changes of calcium channels in SNc dopaminergic neurons. Application of 6-OHDA (0.5-2mM) evoked a dose-dependent, desensitizing inward current and intracellular free calcium concentration ([Ca(2+)]i) rise. In voltage clamp, ω-conotoxin-sensitive Ca(2+) current modulation mediated by 6-OHDA reflected an altered sensitivity. Furthermore, we found that 6-OHDA modulated Ca(2+) currents through PKA pathway. These results provided evidence for the potential role of VGCCs and PKA involved in oxidative stress in degeneration of SNc neurons in Parkinson's disease (PD). Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

q-triplet for Brazos River discharge: The edge of chaos?

NASA Astrophysics Data System (ADS)

Stosic, Tatijana; Stosic, Borko; Singh, Vijay P.

2018-04-01

We study the daily discharge data of Brazos River in Texas, USA, from 1900 to 2017, in terms of concepts drawn from the non-extensive statistics recently introduced by Tsallis. We find that the Brazos River discharge indeed follows non-extensive statistics regarding equilibrium, relaxation and sensitivity. Besides being the first such finding of a full-fledged q-triplet in hydrological data with possible future impact on water resources management, the fact that all three Tsallis q-triplet values are remarkably close to those of the logistic map at the onset of chaos opens up new questions towards a deeper understanding of the Brazos River dynamics, that may prove relevant for hydrological research in a more general sense.

Constitutive BAK activation as a determinant of drug sensitivity in malignant lymphohematopoietic cells

PubMed Central

Dai, Haiming; Ding, Husheng; Meng, X. Wei; Peterson, Kevin L.; Schneider, Paula A.; Karp, Judith E.; Kaufmann, Scott H.

2015-01-01

Mitochondrial outer membrane permeabilization (MOMP), a key step in the intrinsic apoptotic pathway, is incompletely understood. Current models emphasize the role of BH3-only BCL2 family members in BAX and BAK activation. Here we demonstrate concentration-dependent BAK autoactivation under cell-free conditions and provide evidence that this autoactivation plays a key role in regulating the intrinsic apoptotic pathway in intact cells. In particular, we show that up to 80% of BAK (but not BAX) in lymphohematopoietic cell lines is oligomerized and bound to anti-apoptotic BCL2 family members in the absence of exogenous death stimuli. The extent of this constitutive BAK oligomerization is diminished by BAK knockdown and unaffected by BIM or PUMA down-regulation. Further analysis indicates that sensitivity of cells to BH3 mimetics reflects the identity of the anti-apoptotic proteins to which BAK is constitutively bound, with extensive BCLXL•BAK complexes predicting navitoclax sensitivity, and extensive MCL1•BAK complexes predicting A1210477 sensitivity. Moreover, high BAK expression correlates with sensitivity of clinical acute myelogenous leukemia to chemotherapy, whereas low BAK levels correlate with resistance and relapse. Collectively, these results inform current understanding of MOMP and provide new insight into the ability of BH3 mimetics to induce apoptosis without directly activating BAX or BAK. PMID:26494789

A transmission-grating-modulated pump-probe absorption spectroscopy and demonstration of diffusion dynamics of photoexcited carriers in bulk intrinsic GaAs film.

PubMed

Chen, Ke; Wang, Wenfang; Chen, Jianming; Wen, Jinhui; Lai, Tianshu

2012-02-13

A transmission-grating-modulated time-resolved pump-probe absorption spectroscopy is developed and formularized. The spectroscopy combines normal time-resolved pump-probe absorption spectroscopy with a binary transmission grating, is sensitive to the spatiotemporal evolution of photoinjected carriers, and has extensive applicability in the study of diffusion transport dynamics of photoinjected carriers. This spectroscopy has many advantages over reported optical methods to measure diffusion dynamics, such as simple experimental setup and operation, and high detection sensitivity. The measurement of diffusion dynamics is demonstrated on bulk intrinsic GaAs films. A carrier density dependence of carrier diffusion coefficient is obtained and agrees well with reported results.

Sensitivity and Discovery Potential of CUORE to Neutrinoless Double-Beta Decay

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

Alessandria, F; Ardito, R; Artusa, DR

We present a study of the sensitivity and discovery potential of CUORE, a bolometric double-beta decay experiment under construction at the Laboratori Nazionali del Gran Sasso in Italy. Two approaches to the computation of experimental sensitivity for various background scenarios are presented, and an extension of the sensitivity formulation to the discovery potential case is also discussed. Assuming a background rate of 10 -2 cts/(keV kg y), we find that, after 5 years of live time, CUORE has a 1 sigma sensitivity to the neutrinoless double-beta decay half-life of Tmore » $$0v\\atop{1/2}$$(1θ) = 1.6 \\times 10 26 y and thus a potential to probe the effective Majorana neutrino mass down to 40-100 meV; the sensitivity at 1.64 sigma, which corresponds to 90% C.L., will be T$$0v\\atop{1/2}$$(1.64θ) = 9.5 \\times 10 25 y. This range is compared with the claim of observation of neutrinoless double-beta decay in 76Ge and the preferred range of the neutrino mass parameter space from oscillation results.« less

Shelf life extension as solution for environmental impact mitigation: A case study for bakery products.

PubMed

Bacenetti, Jacopo; Cavaliere, Alessia; Falcone, Giacomo; Giovenzana, Valentina; Banterle, Alessandro; Guidetti, Riccardo

2018-06-15

Over the last years, increasing attention has been paid to environmental concerns related to food production and potential solutions to this issue. Among the different strategies being considered to reduce the impact food production has on the environment, only moderate has been paid to the extension of shelf life; a longer shelf life can reduce food losses as well as the economic and environmental impacts of the distribution logistics. The aim of this study is to assess the environmental performance of whole-wheat breadsticks with extended shelf lives and to evaluate whether the shelf-life extension is an effective mitigation solution from an environmental point of view. To this purpose, the life cycle assessment (LCA) approach was applied from a "cradle-to-grave" perspective. Rosmarinic acid was used as an antioxidant to extend the shelf life. To test the robustness of the results and to investigate the influence of the choices made in the modelling phase, a sensitivity and uncertainty analysis were carried out. The achieved results highlighted how, for 10 of the 12 evaluated impact categories, the shelf-life extension is a proper mitigation solution, and its effectiveness depends on the magnitude of product loss reduction that is achieved. The shelf-life extension doesn't allow for the reduction of environmental impact in the categories of human toxicity, cancer effects and freshwater eutrophication. Copyright © 2018 Elsevier B.V. All rights reserved.

Examining the Chemical and Structural Properties that Influence the Sensitivity of Energetic Nitrate Esters

DOE PAGES

Manner, Virginia W.; Cawkwell, Marc; Kober, Edward M.; ...

2018-03-09

The sensitivity of explosives is controlled by factors that span from intrinsic chemical reactivity and chemical intramolecular effects to mesoscale structure and defects, and has been a topic of extensive study for over 50 years. Due to these complex competing chemical and physical elements, a unifying relationship between molecular framework, crystal structure, and sensitivity has yet to be developed. In order to move towards this goal, ideally experimental studies should be performed on systems with small, systematic structural modifications, with modeling utilized to interpret experimental results. Pentaerythritol tetranitrate (PETN) is a common nitrate ester explosive that has been widely studiedmore » due to its use in military and commercial explosives. We have synthesized PETN derivatives with modified sensitivity characteristics by substituting the CCH 2ONO 2 moiety with other substituents, including CH, CNH 2, CNH3X, CCH 3, and PO. We relate the handling sensitivity properties of each PETN derivative to its structural properties, and discuss the potential roles of thermodynamic properties such as heat capacity and heat of formation, thermal stability, crystal structure, compressibility, and inter- and intramolecular hydrogen bonding on impact sensitivity. Reactive molecular dynamics (MD) simulations of the C/H/N/O-based PETN-derivatives have been performed under cook-off conditions that mimic those accessed in impact tests. These simulations infer how changes in chemistry affect the subsequent decomposition pathways.« less

Examining the Chemical and Structural Properties that Influence the Sensitivity of Energetic Nitrate Esters

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

Manner, Virginia W.; Cawkwell, Marc; Kober, Edward M.

The sensitivity of explosives is controlled by factors that span from intrinsic chemical reactivity and chemical intramolecular effects to mesoscale structure and defects, and has been a topic of extensive study for over 50 years. Due to these complex competing chemical and physical elements, a unifying relationship between molecular framework, crystal structure, and sensitivity has yet to be developed. In order to move towards this goal, ideally experimental studies should be performed on systems with small, systematic structural modifications, with modeling utilized to interpret experimental results. Pentaerythritol tetranitrate (PETN) is a common nitrate ester explosive that has been widely studiedmore » due to its use in military and commercial explosives. We have synthesized PETN derivatives with modified sensitivity characteristics by substituting the CCH 2ONO 2 moiety with other substituents, including CH, CNH 2, CNH3X, CCH 3, and PO. We relate the handling sensitivity properties of each PETN derivative to its structural properties, and discuss the potential roles of thermodynamic properties such as heat capacity and heat of formation, thermal stability, crystal structure, compressibility, and inter- and intramolecular hydrogen bonding on impact sensitivity. Reactive molecular dynamics (MD) simulations of the C/H/N/O-based PETN-derivatives have been performed under cook-off conditions that mimic those accessed in impact tests. These simulations infer how changes in chemistry affect the subsequent decomposition pathways.« less

Functional optical coherence tomography: principles and progress

NASA Astrophysics Data System (ADS)

Kim, Jina; Brown, William; Maher, Jason R.; Levinson, Howard; Wax, Adam

2015-05-01

In the past decade, several functional extensions of optical coherence tomography (OCT) have emerged, and this review highlights key advances in instrumentation, theoretical analysis, signal processing and clinical application of these extensions. We review five principal extensions: Doppler OCT (DOCT), polarization-sensitive OCT (PS-OCT), optical coherence elastography (OCE), spectroscopic OCT (SOCT), and molecular imaging OCT. The former three have been further developed with studies in both ex vivo and in vivo human tissues. This review emphasizes the newer techniques of SOCT and molecular imaging OCT, which show excellent potential for clinical application but have yet to be well reviewed in the literature. SOCT elucidates tissue characteristics, such as oxygenation and carcinogenesis, by detecting wavelength-dependent absorption and scattering of light in tissues. While SOCT measures endogenous biochemical distributions, molecular imaging OCT detects exogenous molecular contrast agents. These newer advances in functional OCT broaden the potential clinical application of OCT by providing novel ways to understand tissue activity that cannot be accomplished by other current imaging methodologies.

Functional Optical Coherence Tomography: Principles and Progress

PubMed Central

Kim, Jina; Brown, William; Maher, Jason R.; Levinson, Howard; Wax, Adam

2015-01-01

In the past decade, several functional extensions of optical coherence tomography (OCT) have emerged, and this review highlights key advances in instrumentation, theoretical analysis, signal processing and clinical application of these extensions. We review five principal extensions: Doppler OCT (DOCT), polarization-sensitive OCT (PS-OCT), optical coherence elastography (OCE), spectroscopic OCT (SOCT), and molecular imaging OCT. The former three have been further developed with studies in both ex vivo and in vivo human tissues. This review emphasizes the newer techniques of SOCT and molecular imaging OCT, which show excellent potential for clinical application but have yet to be well reviewed in the literature. SOCT elucidates tissue characteristics, such as oxygenation and carcinogenesis, by detecting wavelength-dependent absorption and scattering of light in tissues. While SOCT measures endogenous biochemical distributions, molecular imaging OCT detects exogenous molecular contrast agents. These newer advances in functional OCT broaden the potential clinical application of OCT by providing novel ways to understand tissue activity that cannot be accomplished by other current imaging methodologies. PMID:25951836

One Facility's Experience Using the Community Readiness Model to Guide Services for Gay, Lesbian, Bisexual, and Transgender Older Adults

ERIC Educational Resources Information Center

Carlson, Laurie A.; Harper, Kelly S.

2011-01-01

Service provision to gay, lesbian, bisexual, and transgender (GLBT) older adults is a dynamic and sensitive area, requiring rigorous and extensive inquiry and action. Examining the readiness and assets of organizations serving GLBT older adults requires not only heart and sensitivity but also resources and a clear vision. The Community Readiness…

10 CFR 2.307 - Extension and reduction of time limits; delegated authority to order use of procedures for access...

Code of Federal Regulations, 2010 CFR

2010-01-01

... authority to order use of procedures for access by potential parties to certain sensitive unclassified... authority to order use of procedures for access by potential parties to certain sensitive unclassified... Commission or the presiding officer. (b) If this part does not prescribe a time limit for an action to be...

Enviromentally sensitive patch index of desertification risk applied to the main habitats of Sicily

NASA Astrophysics Data System (ADS)

Duro, A.; Piccione, V.; Ragusa, M. A.; Rapicavoli, V.; Veneziano, V.

2017-07-01

The authors applied the MEDALUS - Mediterranean Desertification and Land Use - procedure to the most representative sicilian habitat by extension, socio-economic and environmental importance, in order to assess the risk of desertification. Thanks to the ESPI, Environmentally Sensitive Patch Index, in this paper the authors estimate the current and future regional levels of desertification risk.

Piezoresistive Cantilever Performance—Part I: Analytical Model for Sensitivity

PubMed Central

Park, Sung-Jin; Doll, Joseph C.; Pruitt, Beth L.

2010-01-01

An accurate analytical model for the change in resistance of a piezoresistor is necessary for the design of silicon piezoresistive transducers. Ion implantation requires a high-temperature oxidation or annealing process to activate the dopant atoms, and this treatment results in a distorted dopant profile due to diffusion. Existing analytical models do not account for the concentration dependence of piezoresistance and are not accurate for nonuniform dopant profiles. We extend previous analytical work by introducing two nondimensional factors, namely, the efficiency and geometry factors. A practical benefit of this efficiency factor is that it separates the process parameters from the design parameters; thus, designers may address requirements for cantilever geometry and fabrication process independently. To facilitate the design process, we provide a lookup table for the efficiency factor over an extensive range of process conditions. The model was validated by comparing simulation results with the experimentally determined sensitivities of piezoresistive cantilevers. We performed 9200 TSUPREM4 simulations and fabricated 50 devices from six unique process flows; we systematically explored the design space relating process parameters and cantilever sensitivity. Our treatment focuses on piezoresistive cantilevers, but the analytical sensitivity model is extensible to other piezoresistive transducers such as membrane pressure sensors. PMID:20336183

Piezoresistive Cantilever Performance-Part I: Analytical Model for Sensitivity.

PubMed

Park, Sung-Jin; Doll, Joseph C; Pruitt, Beth L

2010-02-01

An accurate analytical model for the change in resistance of a piezoresistor is necessary for the design of silicon piezoresistive transducers. Ion implantation requires a high-temperature oxidation or annealing process to activate the dopant atoms, and this treatment results in a distorted dopant profile due to diffusion. Existing analytical models do not account for the concentration dependence of piezoresistance and are not accurate for nonuniform dopant profiles. We extend previous analytical work by introducing two nondimensional factors, namely, the efficiency and geometry factors. A practical benefit of this efficiency factor is that it separates the process parameters from the design parameters; thus, designers may address requirements for cantilever geometry and fabrication process independently. To facilitate the design process, we provide a lookup table for the efficiency factor over an extensive range of process conditions. The model was validated by comparing simulation results with the experimentally determined sensitivities of piezoresistive cantilevers. We performed 9200 TSUPREM4 simulations and fabricated 50 devices from six unique process flows; we systematically explored the design space relating process parameters and cantilever sensitivity. Our treatment focuses on piezoresistive cantilevers, but the analytical sensitivity model is extensible to other piezoresistive transducers such as membrane pressure sensors.

Stimuli-Responsive NO Release for On-Demand Gas-Sensitized Synergistic Cancer Therapy.

PubMed

Fan, Wenpei; Yung, Bryant C; Chen, Xiaoyuan

2018-03-08

Featuring high biocompatibility, the emerging field of gas therapy has attracted extensive attention in the medical and scientific communities. Currently, considerable research has focused on the gasotransmitter nitric oxide (NO) owing to its unparalleled dual roles in directly killing cancer cells at high concentrations and cooperatively sensitizing cancer cells to other treatments for synergistic therapy. Of particular note, recent state-of-the-art studies have turned our attention to the chemical design of various endogenous/exogenous stimuli-responsive NO-releasing nanomedicines and their biomedical applications for on-demand NO-sensitized synergistic cancer therapy, which are discussed in this Minireview. Moreover, the potential challenges regarding NO gas therapy are also described, aiming to advance the development of NO nanomedicines as well as usher in new frontiers in this fertile research area. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highly stretchable and wearable graphene strain sensors with controllable sensitivity for human motion monitoring.

PubMed

Park, Jung Jin; Hyun, Woo Jin; Mun, Sung Cik; Park, Yong Tae; Park, O Ok

2015-03-25

Because of their outstanding electrical and mechanical properties, graphene strain sensors have attracted extensive attention for electronic applications in virtual reality, robotics, medical diagnostics, and healthcare. Although several strain sensors based on graphene have been reported, the stretchability and sensitivity of these sensors remain limited, and also there is a pressing need to develop a practical fabrication process. This paper reports the fabrication and characterization of new types of graphene strain sensors based on stretchable yarns. Highly stretchable, sensitive, and wearable sensors are realized by a layer-by-layer assembly method that is simple, low-cost, scalable, and solution-processable. Because of the yarn structures, these sensors exhibit high stretchability (up to 150%) and versatility, and can detect both large- and small-scale human motions. For this study, wearable electronics are fabricated with implanted sensors that can monitor diverse human motions, including joint movement, phonation, swallowing, and breathing.

A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems

PubMed Central

Choi, Donghee; Kim, Dohoon; Park, Seog

2015-01-01

Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013

Sensitivity analysis for missing dichotomous outcome data in multi-visit randomized clinical trial with randomization-based covariance adjustment.

PubMed

Li, Siying; Koch, Gary G; Preisser, John S; Lam, Diana; Sanchez-Kam, Matilde

2017-01-01

Dichotomous endpoints in clinical trials have only two possible outcomes, either directly or via categorization of an ordinal or continuous observation. It is common to have missing data for one or more visits during a multi-visit study. This paper presents a closed form method for sensitivity analysis of a randomized multi-visit clinical trial that possibly has missing not at random (MNAR) dichotomous data. Counts of missing data are redistributed to the favorable and unfavorable outcomes mathematically to address possibly informative missing data. Adjusted proportion estimates and their closed form covariance matrix estimates are provided. Treatment comparisons over time are addressed with Mantel-Haenszel adjustment for a stratification factor and/or randomization-based adjustment for baseline covariables. The application of such sensitivity analyses is illustrated with an example. An appendix outlines an extension of the methodology to ordinal endpoints.

Verification bias: an under-recognized source of error in assessing the efficacy of MRI of the meniscii.

PubMed

Richardson, Michael L; Petscavage, Jonelle M

2011-11-01

The sensitivity and specificity of magnetic resonance imaging (MRI) for diagnosis of meniscal tears has been studied extensively, with tears usually verified by surgery. However, surgically unverified cases are often not considered in these studies, leading to verification bias, which can falsely increase the sensitivity and decrease the specificity estimates. Our study suggests that such bias may be very common in the meniscal MRI literature, and illustrates techniques to detect and correct for such bias. PubMed was searched for articles estimating sensitivity and specificity of MRI for meniscal tears. These were assessed for verification bias, deemed potentially present if a study included any patients whose MRI findings were not surgically verified. Retrospective global sensitivity analysis (GSA) was performed when possible. Thirty-nine of the 314 studies retrieved from PubMed specifically dealt with meniscal tears. All 39 included unverified patients, and hence, potential verification bias. Only seven articles included sufficient information to perform GSA. Of these, one showed definite verification bias, two showed no bias, and four others showed bias within certain ranges of disease prevalence. Only 9 of 39 acknowledged the possibility of verification bias. Verification bias is underrecognized and potentially common in published estimates of the sensitivity and specificity of MRI for the diagnosis of meniscal tears. When possible, it should be avoided by proper study design. If unavoidable, it should be acknowledged. Investigators should tabulate unverified as well as verified data. Finally, verification bias should be estimated; if present, corrected estimates of sensitivity and specificity should be used. Our online web-based calculator makes this process relatively easy. Copyright © 2011 AUR. Published by Elsevier Inc. All rights reserved.

Use of insulin sensitizers for the treatment of major depressive disorder: a pilot study of pioglitazone for major depression accompanied by abdominal obesity.

PubMed

Kemp, David E; Ismail-Beigi, Faramarz; Ganocy, Stephen J; Conroy, Carla; Gao, Keming; Obral, Sarah; Fein, Elizabeth; Findling, Robert L; Calabrese, Joseph R

2012-02-01

This study was conducted to examine the safety and efficacy of pioglitazone, a thiazolidinedione insulin sensitizer, in adult outpatients with major depressive disorder. In a 12-week, open-label, flexible-dose study, 23 patients with major depressive disorder received pioglitazone monotherapy or adjunctive therapy initiated at 15 mg daily. Subjects were required to meet criteria for abdominal obesity (waist circumference>35 in. in women and >40 in. in men) or metabolic syndrome. The primary efficacy measure was the change from baseline to Week 12 on the Inventory of Depressive Symptomatology (IDS) total score. Partial responders (≥25% decrease in IDS total score) were eligible to participate in an optional extension phase for an additional three months. Pioglitazone decreased depression symptom severity from a total IDS score of 40.3±1.8 to 19.2±1.8 at Week 12 (p<.001). Among partial responders (≥25% decrease in IDS total score), an improvement in depressive symptoms was maintained during an additional 3-month extension phase (total duration=24 weeks) according to IDS total scores (p<.001). Patients experienced a reduction in insulin resistance from baseline to Week 12 according to the log homeostasis model assessment (-0.8±0.75; p<.001) and a significant reduction in inflammation as measured by log highly- sensitive C-reactive protein (-0.87±0.72; p<.001). During the current episode, the majority of participants (74%, n=17), had already failed at least one antidepressant trial. The most common side effects were headache and dizziness; no patient discontinued due to side effects. These data are limited by a small sample size and an open-label study design with no placebo control. Although preliminary, pioglitazone appears to reduce depression severity and improve several markers of cardiometabolic risk, including insulin resistance and inflammation. Larger, placebo-controlled studies are indicated. Copyright © 2011 Elsevier B.V. All rights reserved.

Darwin's bee-trap: The kinetics of Catasetum, a new world orchid.

PubMed

Nicholson, Charles C; Bales, James W; Palmer-Fortune, Joyce E; Nicholson, Robert G

2008-01-01

The orchid genera Catasetum employs a hair-trigger activated, pollen release mechanism, which forcibly attaches pollen sacs onto foraging insects in the New World tropics. This remarkable adaptation was studied extensively by Charles Darwin and he termed this rapid response "sensitiveness." Using high speed video cameras with a frame speed of 1000 fps, this rapid release was filmed and from the subsequent footage, velocity, speed, acceleration, force and kinetic energy were computed.

[The modified method registration of kinesthetic evoked potentials and its application for research of proprioceptive sensitivity disorders at spondylogenic cervical myelopathy].

PubMed

Gordeev, S A; Voronin, S G

2016-01-01

To analyze the efficacy of modified (passive radiocarpal articulation flexion/extension) and «standard» (passive radiocarpal articulation flexion) methods of kinesthetic evoked potentials for proprioceptive sensitivity assessment in healthy subjects and patients with spondylotic cervical myelopathy. The study included 14 healthy subjects (4 women and 10 men, mean age 54.1±10.5 years) and 8 patients (2 women and 6 men, mean age 55.8±10.9 years) with spondylotic cervical myelopathy. Muscle-joint sensation was examined during the clinical study. A modified method of kinesthetic evoked potentials was developed. This method differed from the "standard" one by the organization of a cycle including several passive movements,where each new movement differed from the preceding one by the direction. The modified method of kinesthetic evoked potentials ensures more reliable kinesthetic sensitivity assessment due to movement variability. Asignificant increaseof the latent periods of the early components of the response was found in patients compared to healthy subjects. The modified method of kinesthetic evoked potentials can be used for objective diagnosis of proprioceptive sensitivity disorders in patients with spondylotic cervical myelopathy.

Perovskite nanoparticle-sensitized Ga 2O 3 nanorod arrays for CO detection at high temperature

DOE PAGES

Lin, Hui -Jan; Baltrus, John P.; Gao, Haiyong; ...

2016-04-04

Here, noble metal nanoparticles are extensively used for sensitizing metal oxide chemical sensors through the catalytic spillover mechanism. However, due to earth-scarcity and high cost of noble metals, finding replacements presents a great economic benefit. Besides, high temperature and harsh environment sensor applications demand material stability under conditions approaching thermal and chemical stability limits of noble metals. In this study, we employed thermally stable perovskite-type La 0.8Sr 0.2FeO 3 (LSFO) nanoparticle surface decoration on Ga 2O 3 nanorod array gas sensors and discovered an order of magnitude enhanced sensitivity to carbon monoxide at 500 °C. The LSFO nanoparticle catalysts wasmore » of comparable performance to that achieved by Pt nanoparticles, with a much lower weight loading than Pt. Detailed electron microscopy and X-ray photoelectron spectroscopy studies suggested the LSFO nanoparticle sensitization effect is attributed to a spillover-like effect associated with the gas-LSFO-Ga 2O 3 triple-interfaces that spread the negatively charged surface oxygen ions from LSFO nanoparticles surfaces over to β-Ga 2O 3 nanorod surfaces with faster surface CO oxidation reactions.« less

Perovskite Nanoparticle-Sensitized Ga2O3 Nanorod Arrays for CO Detection at High Temperature.

PubMed

Lin, Hui-Jan; Baltrus, John P; Gao, Haiyong; Ding, Yong; Nam, Chang-Yong; Ohodnicki, Paul; Gao, Pu-Xian

2016-04-13

Noble metal nanoparticles are extensively used for sensitizing metal oxide chemical sensors through the catalytic spillover mechanism. However, due to earth-scarcity and high cost of noble metals, finding replacements presents a great economic benefit. Besides, high temperature and harsh environment sensor applications demand material stability under conditions approaching thermal and chemical stability limits of noble metals. In this study, we employed thermally stable perovskite-type La(0.8)Sr(0.2)FeO3 (LSFO) nanoparticle surface decoration on Ga2O3 nanorod array gas sensors and discovered an order of magnitude enhanced sensitivity to carbon monoxide at 500 °C. The LSFO nanoparticle catalysts was of comparable performance to that achieved by Pt nanoparticles, with a much lower weight loading than Pt. Detailed electron microscopy and X-ray photoelectron spectroscopy studies suggested the LSFO nanoparticle sensitization effect is attributed to a spillover-like effect associated with the gas-LSFO-Ga2O3 triple-interfaces that spread the negatively charged surface oxygen ions from LSFO nanoparticles surfaces over to β-Ga2O3 nanorod surfaces with faster surface CO oxidation reactions.

Protein Detection Using the Multiplexed Proximity Extension Assay (PEA) from Plasma and Vaginal Fluid Applied to the Indicating FTA Elute Micro Card™

PubMed Central

Berggrund, Malin; Ekman, Daniel; Gustavsson, Inger; Sundfeldt, Karin; Olovsson, Matts; Enroth, Stefan; Gyllensten, Ulf

2016-01-01

The indicating FTA elute micro card™ has been developed to collect and stabilize the nucleic acid in biological samples and is widely used in human and veterinary medicine and other disciplines. This card is not recommended for protein analyses, since surface treatment may denature proteins. We studied the ability to analyse proteins in human plasma and vaginal fluid as applied to the indicating FTA elute micro card™ using the sensitive proximity extension assay (PEA). Among 92 proteins in the Proseek Multiplex Oncology Iv2 panel, 87 were above the limit of detection (LOD) in liquid plasma and 56 among 92 above LOD in plasma applied to FTA cards. Washing and protein elution protocols were compared to identify an optimal method. Liquid-based cytology samples showed a lower number of proteins above LOD than FTA cards with vaginal fluid samples applied. Our results demonstrate that samples applied to the indicating FTA elute micro card™ are amendable to protein analyses, given that a sensitive protein detection assay is used. The results imply that biological samples applied to FTA cards can be used for DNA, RNA and protein detection. PMID:28936257

Protein Detection Using the Multiplexed Proximity Extension Assay (PEA) from Plasma and Vaginal Fluid Applied to the Indicating FTA Elute Micro Card™.

PubMed

Berggrund, Malin; Ekman, Daniel; Gustavsson, Inger; Sundfeldt, Karin; Olovsson, Matts; Enroth, Stefan; Gyllensten, Ulf

2016-01-01

The indicating FTA elute micro card™ has been developed to collect and stabilize the nucleic acid in biological samples and is widely used in human and veterinary medicine and other disciplines. This card is not recommended for protein analyses, since surface treatment may denature proteins. We studied the ability to analyse proteins in human plasma and vaginal fluid as applied to the indicating FTA elute micro card™ using the sensitive proximity extension assay (PEA). Among 92 proteins in the Proseek Multiplex Oncology Iv2 panel, 87 were above the limit of detection (LOD) in liquid plasma and 56 among 92 above LOD in plasma applied to FTA cards. Washing and protein elution protocols were compared to identify an optimal method. Liquid-based cytology samples showed a lower number of proteins above LOD than FTA cards with vaginal fluid samples applied. Our results demonstrate that samples applied to the indicating FTA elute micro card™ are amendable to protein analyses, given that a sensitive protein detection assay is used. The results imply that biological samples applied to FTA cards can be used for DNA, RNA and protein detection.

[Insulinoma of the pancreas: analysis of a clinical series of 30 cases].

PubMed

Andronesi, D; Andronesi, A; Tonea, A; Andrei, S; Herlea, V; Lupescu, I; Ionescu-Târgovişte, C; Coculescu, M; Fica, S; Ionescu, M; Gheorghe, C; Popescu, I

2009-01-01

Insulinoma is the most frequent neuroendocrine pancreatic tumor and is the main cause for hypoglicemia due to endogenous hyperinsulinism. We performed an analysis of a clinical series in order to study the clinical and biological spectrum of presentation, the preoperatory imagistic diagnosis and results of the surgical approach. Between 1986-2009, 30 patients with symptoms suggesting an insulinoma were hospitalized in our department. Preoperatory localization of insulinomas was possible in 16 patients. The most sensitive imagistic methods were ecoendoscopy and magnetic resonance. Intraoperatory ultrasound was performed in 16 patients and its sensitivity in detection of insulinomas was 93%; the combination between intraoperative ultrasound and manual exploration of pancreas by the surgeon reached a 100% sensitivity. Before the intraoperatory ultrasound was used the tumor excision was predominantly done by extensive pancreatic resection, while after this was available in our centre more conservative (enucleo-resection) procedures were chosen. In 1 patient the resection was done by laparoscopy, and in 1 patient by robotic surgery. The dimensions of the tumor were less than 2 cm in most of the patients; 2 had nesidioblastosis and 2 had multiple insulinomas; all 28 patients proved to have benign insulinomas at histological specimens. Following surgery, the symptoms disappear in all patients. The most common complication following extensive pancreatic resections was acute pancreatitis, while after enucleation pancreatic fistula occurred more frequently. Due to small dimensions, the preoperative diagnosis of insulinomas is usually difficult, ecoendoscopy being the most sensitive method. Intraoperative ultrasound is essential for insulinoma localization and for chosing the optimal type of excision. Enucleation is the resection method to be chosen whenever this it is technical possible. In benign insulinomas the prognosis is excellent, surgical resection being curative in all cases.

Prognostic impact of paraneoplastic cushing's syndrome in small-cell lung cancer.

PubMed

Nagy-Mignotte, Hélène; Shestaeva, Oxana; Vignoud, Lucile; Guillem, Pascale; Ruckly, Stéphane; Chabre, Olivier; Sakhri, Linda; Duruisseaux, Michael; Mousseau, Mireille; Timsit, Jean-François; Moro-Sibilot, Denis

2014-04-01

Paraneoplastic Cushing's syndrome (CushingPS) in small-cell lung cancer is rare but severe. We studied 383 patients with small-cell lung cancer diagnosed between 1998 and 2012. Among them, 23 patients had CushingPS, 56 had other paraneoplastic syndrome (OtherPS), and 304 had no paraneoplastic syndrome (NoPS). After comparison of the three groups, we observed that CushingPS patients had more extensive disease: 82.6% versus 67.8% versus 53.3% (p = 0.005), respectively, with more than two metastatic sites: 63.2% versus 15.8% and 24.1% (p ≤ 0.001), a higher World Health Organization performance status (2-4): 73.9% versus 57.1% versus 43.7% (p = 0.006), greater weight loss (≥10%): 47.8% versus 33.9% versus 16.4% (p ≤ 0.001), reduced objective response to first-line treatment: 47.6% versus 74.1% versus 71.1% (p = 0.04), and poorer sensitivity to first-line treatment: 19% versus 38.9% versus 48.6% (p = 0.01). NoPS patients, with World Health Organization performance status of 3-4, had extensive disease at diagnosis, with response, sensitivity to first-line treatment, and survival similar to the CushingPS group. At relapse, the CushingPS group had no objective response to second-line treatment versus 25% versus 42.8% in OtherPS and NoPS groups, respectively (p = 0.005). The median survival of CushingPS patients was 6.6 months versus 9.2 months for OtherPS and 13.1 months for NoPS patients (p ≤ 0.001). CushingPS is a prognostic factor of death (hazard ratio, 2.31; p ≤ 0.001). CushingPS is the worst form of the paraneoplastic syndromes with particularly extensive tumors. Reduced objective response and sensitivity to first-line treatment and no response to second-line treatment suggest starting palliative care early at first line and exclusively at relapse.

Contextual sensitivity in scientific reproducibility

PubMed Central

Van Bavel, Jay J.; Mende-Siedlecki, Peter; Brady, William J.; Reinero, Diego A.

2016-01-01

In recent years, scientists have paid increasing attention to reproducibility. For example, the Reproducibility Project, a large-scale replication attempt of 100 studies published in top psychology journals found that only 39% could be unambiguously reproduced. There is a growing consensus among scientists that the lack of reproducibility in psychology and other fields stems from various methodological factors, including low statistical power, researcher’s degrees of freedom, and an emphasis on publishing surprising positive results. However, there is a contentious debate about the extent to which failures to reproduce certain results might also reflect contextual differences (often termed “hidden moderators”) between the original research and the replication attempt. Although psychologists have found extensive evidence that contextual factors alter behavior, some have argued that context is unlikely to influence the results of direct replications precisely because these studies use the same methods as those used in the original research. To help resolve this debate, we recoded the 100 original studies from the Reproducibility Project on the extent to which the research topic of each study was contextually sensitive. Results suggested that the contextual sensitivity of the research topic was associated with replication success, even after statistically adjusting for several methodological characteristics (e.g., statistical power, effect size). The association between contextual sensitivity and replication success did not differ across psychological subdisciplines. These results suggest that researchers, replicators, and consumers should be mindful of contextual factors that might influence a psychological process. We offer several guidelines for dealing with contextual sensitivity in reproducibility. PMID:27217556

Contextual sensitivity in scientific reproducibility.

PubMed

Van Bavel, Jay J; Mende-Siedlecki, Peter; Brady, William J; Reinero, Diego A

2016-06-07

In recent years, scientists have paid increasing attention to reproducibility. For example, the Reproducibility Project, a large-scale replication attempt of 100 studies published in top psychology journals found that only 39% could be unambiguously reproduced. There is a growing consensus among scientists that the lack of reproducibility in psychology and other fields stems from various methodological factors, including low statistical power, researcher's degrees of freedom, and an emphasis on publishing surprising positive results. However, there is a contentious debate about the extent to which failures to reproduce certain results might also reflect contextual differences (often termed "hidden moderators") between the original research and the replication attempt. Although psychologists have found extensive evidence that contextual factors alter behavior, some have argued that context is unlikely to influence the results of direct replications precisely because these studies use the same methods as those used in the original research. To help resolve this debate, we recoded the 100 original studies from the Reproducibility Project on the extent to which the research topic of each study was contextually sensitive. Results suggested that the contextual sensitivity of the research topic was associated with replication success, even after statistically adjusting for several methodological characteristics (e.g., statistical power, effect size). The association between contextual sensitivity and replication success did not differ across psychological subdisciplines. These results suggest that researchers, replicators, and consumers should be mindful of contextual factors that might influence a psychological process. We offer several guidelines for dealing with contextual sensitivity in reproducibility.

DGSA: A Matlab toolbox for distance-based generalized sensitivity analysis of geoscientific computer experiments

NASA Astrophysics Data System (ADS)

Park, Jihoon; Yang, Guang; Satija, Addy; Scheidt, Céline; Caers, Jef

2016-12-01

Sensitivity analysis plays an important role in geoscientific computer experiments, whether for forecasting, data assimilation or model calibration. In this paper we focus on an extension of a method of regionalized sensitivity analysis (RSA) to applications typical in the Earth Sciences. Such applications involve the building of large complex spatial models, the application of computationally extensive forward modeling codes and the integration of heterogeneous sources of model uncertainty. The aim of this paper is to be practical: 1) provide a Matlab code, 2) provide novel visualization methods to aid users in getting a better understanding in the sensitivity 3) provide a method based on kernel principal component analysis (KPCA) and self-organizing maps (SOM) to account for spatial uncertainty typical in Earth Science applications and 4) provide an illustration on a real field case where the above mentioned complexities present themselves. We present methods that extend the original RSA method in several ways. First we present the calculation of conditional effects, defined as the sensitivity of a parameter given a level of another parameters. Second, we show how this conditional effect can be used to choose nominal values or ranges to fix insensitive parameters aiming to minimally affect uncertainty in the response. Third, we develop a method based on KPCA and SOM to assign a rank to spatial models in order to calculate the sensitivity on spatial variability in the models. A large oil/gas reservoir case is used as illustration of these ideas.

A gaze-contingent display to study contrast sensitivity under natural viewing conditions

NASA Astrophysics Data System (ADS)

Dorr, Michael; Bex, Peter J.

2011-03-01

Contrast sensitivity has been extensively studied over the last decades and there are well-established models of early vision that were derived by presenting the visual system with synthetic stimuli such as sine-wave gratings near threshold contrasts. Natural scenes, however, contain a much wider distribution of orientations, spatial frequencies, and both luminance and contrast values. Furthermore, humans typically move their eyes two to three times per second under natural viewing conditions, but most laboratory experiments require subjects to maintain central fixation. We here describe a gaze-contingent display capable of performing real-time contrast modulations of video in retinal coordinates, thus allowing us to study contrast sensitivity when dynamically viewing dynamic scenes. Our system is based on a Laplacian pyramid for each frame that efficiently represents individual frequency bands. Each output pixel is then computed as a locally weighted sum of pyramid levels to introduce local contrast changes as a function of gaze. Our GPU implementation achieves real-time performance with more than 100 fps on high-resolution video (1920 by 1080 pixels) and a synthesis latency of only 1.5ms. Psychophysical data show that contrast sensitivity is greatly decreased in natural videos and under dynamic viewing conditions. Synthetic stimuli therefore only poorly characterize natural vision.

Culturally sensitive substance use treatment for racial/ethnic minority youth: A meta-analytic review.

PubMed

Steinka-Fry, Katarzyna T; Tanner-Smith, Emily E; Dakof, Gayle A; Henderson, Craig

2017-04-01

This systematic review and meta-analysis synthesized findings from studies examining culturally sensitive substance use treatment for racial/ethnic minority youth. An extensive literature search located eight eligible studies using experimental or quasi-experimental designs. The meta-analysis quantitatively synthesized findings comparing seven culturally sensitive treatment conditions to seven alternative conditions on samples composed of at least 90% racial/ethnic minority youth. The results from the meta-analysis indicated that culturally sensitive treatments were associated with significantly larger reductions in post-treatment substance use levels relative to their comparison conditions (g=0.37, 95% CI [0.12, 0.62], k=7, total number participants=723). The average time between pretest and posttest was 21weeks (SD=11.79). There was a statistically significant amount of heterogeneity across the seven studies (Q=26.5, p=0.00, τ 2 =0.08, I 2 =77.4%). Differential effects were not statistically significant when contrasts were active generic counterparts of treatment conditions (direct "bona fide" comparisons; g=-0.08, 95% CI [-0.51, 0.35]) and 'treatment as usual' conditions (g=0.39, 95% CI [-0.14, 0.91]). Strong conclusions from the review were hindered by the small number of available studies for synthesis, variability in comparison conditions across studies, and lack of diversity in the adolescent clients served in the studies. Nonetheless, this review suggests that culturally sensitive treatments offer promise as an effective way to address substance use among racial/ethnic minority youth. Copyright © 2017 Elsevier Inc. All rights reserved.

Sensitivity study of Space Station Freedom operations cost and selected user resources

NASA Technical Reports Server (NTRS)

Accola, Anne; Fincannon, H. J.; Williams, Gregory J.; Meier, R. Timothy

1990-01-01

The results of sensitivity studies performed to estimate probable ranges for four key Space Station parameters using the Space Station Freedom's Model for Estimating Space Station Operations Cost (MESSOC) are discussed. The variables examined are grouped into five main categories: logistics, crew, design, space transportation system, and training. The modification of these variables implies programmatic decisions in areas such as orbital replacement unit (ORU) design, investment in repair capabilities, and crew operations policies. The model utilizes a wide range of algorithms and an extensive trial logistics data base to represent Space Station operations. The trial logistics data base consists largely of a collection of the ORUs that comprise the mature station, and their characteristics based on current engineering understanding of the Space Station. A nondimensional approach is used to examine the relative importance of variables on parameters.

Tiltrotor Aeroacoustic Code (TRAC) Prediction Assessment and Initial Comparisons with Tram Test Data

NASA Technical Reports Server (NTRS)

Burley, Casey L.; Brooks, Thomas F.; Charles, Bruce D.; McCluer, Megan

1999-01-01

A prediction sensitivity assessment to inputs and blade modeling is presented for the TiltRotor Aeroacoustic Code (TRAC). For this study, the non-CFD prediction system option in TRAC is used. Here, the comprehensive rotorcraft code, CAMRAD.Mod1, coupled with the high-resolution sectional loads code HIRES, predicts unsteady blade loads to be used in the noise prediction code WOPWOP. The sensitivity of the predicted blade motions, blade airloads, wake geometry, and acoustics is examined with respect to rotor rpm, blade twist and chord, and to blade dynamic modeling. To accomplish this assessment, an interim input-deck for the TRAM test model and an input-deck for a reference test model are utilized in both rigid and elastic modes. Both of these test models are regarded as near scale models of the V-22 proprotor (tiltrotor). With basic TRAC sensitivities established, initial TRAC predictions are compared to results of an extensive test of an isolated model proprotor. The test was that of the TiltRotor Aeroacoustic Model (TRAM) conducted in the Duits-Nederlandse Windtunnel (DNW). Predictions are compared to measured noise for the proprotor operating over an extensive range of conditions. The variation of predictions demonstrates the great care that must be taken in defining the blade motion. However, even with this variability, the predictions using the different blade modeling successfully capture (bracket) the levels and trends of the noise for conditions ranging from descent to ascent.

Tiltrotor Aeroacoustic Code (TRAC) Prediction Assessment and Initial Comparisons With TRAM Test Data

NASA Technical Reports Server (NTRS)

Burley, Casey L.; Brooks, Thomas F.; Charles, Bruce D.; McCluer, Megan

1999-01-01

A prediction sensitivity assessment to inputs and blade modeling is presented for the TiltRotor Aeroacoustic Code (TRAC). For this study, the non-CFD prediction system option in TRAC is used. Here, the comprehensive rotorcraft code, CAMRAD.Mod 1, coupled with the high-resolution sectional loads code HIRES, predicts unsteady blade loads to be used in the noise prediction code WOPWOP. The sensitivity of the predicted blade motions, blade airloads, wake geometry, and acoustics is examined with respect to rotor rpm, blade twist and chord, and to blade dynamic modeling. To accomplish this assessment. an interim input-deck for the TRAM test model and an input-deck for a reference test model are utilized in both rigid and elastic modes. Both of these test models are regarded as near scale models of the V-22 proprotor (tiltrotor). With basic TRAC sensitivities established, initial TRAC predictions are compared to results of an extensive test of an isolated model proprotor. The test was that of the TiltRotor Aeroacoustic Model (TRAM) conducted in the Duits-Nederlandse Windtunnel (DNW). Predictions are compared to measured noise for the proprotor operating over an extensive range of conditions. The variation of predictions demonstrates the great care that must be taken in defining the blade motion. However, even with this variability, the predictions using the different blade modeling successfully capture (bracket) the levels and trends of the noise for conditions ranging from descent to ascent.

Evaluation of markers for CpG island methylator phenotype (CIMP) in colorectal cancer by a large population-based sample.

PubMed

Ogino, Shuji; Kawasaki, Takako; Kirkner, Gregory J; Kraft, Peter; Loda, Massimo; Fuchs, Charles S

2007-07-01

The CpG island methylator phenotype (CIMP or CIMP-high) with extensive promoter methylation is a distinct phenotype in colorectal cancer. However, a choice of markers for CIMP has been controversial. A recent extensive investigation has selected five methylation markers (CACNA1G, IGF2, NEUROG1, RUNX3, and SOCS1) as surrogate markers for epigenomic aberrations in tumor. The use of these markers as a CIMP-specific panel needs to be validated by an independent, large dataset. Using MethyLight assays on 920 colorectal cancers from two large prospective cohort studies, we quantified DNA methylation in eight CIMP-specific markers [the above five plus CDKN2A (p16), CRABP1, and MLH1]. A CIMP-high cutoff was set at > or = 6/8 or > or = 5/8 methylated promoters, based on tumor distribution and BRAF/KRAS mutation frequencies. All but two very specific markers [MLH1 (98% specific) and SOCS1 (93% specific)] demonstrated > or = 85% sensitivity and > or = 80% specificity, indicating overall good concordance in methylation patterns and good performance of these markers. Based on sensitivity, specificity, and false positives and negatives, the eight markers were ranked in order as: RUNX3, CACNA1G, IGF2, MLH1, NEUROG1, CRABP1, SOCS1, and CDKN2A. In conclusion, a panel of markers including at least RUNX3, CACNA1G, IGF2, and MLH1 can serve as a sensitive and specific marker panel for CIMP-high.

[Particular aspects of rhinitis and rhino-conjunctivitis].

PubMed

Favennec, F; Sonneville, A; De Luca, H; Castros, A

2003-03-01

The authors report their experience of 28 years of practice in the opthalmology service of the CHRU at Rennes. The describe certain particular aspects of rhinitis and rhino-conjuctivitis where the danger resides in an extensive risk to the uvula or the bronchi. They insist on the importance of understanding polyvalents in internal medicine (rôle of the seat of gingivodentary "ideas", value of research into indicative markers of protection A2 and B40 in the HLA system. In the region of nutrition, they emphasize the importance of the rôle of zinc, of vitamin C and of magnesium. They base their hopes on study of the local markers of sensitivity, in order to assess the elements of preventative action for an eventual ocular and bronchial extension.

Single Pass Streaming BLAST on FPGAs*†

PubMed Central

Herbordt, Martin C.; Model, Josh; Sukhwani, Bharat; Gu, Yongfeng; VanCourt, Tom

2008-01-01

Approximate string matching is fundamental to bioinformatics and has been the subject of numerous FPGA acceleration studies. We address issues with respect to FPGA implementations of both BLAST- and dynamic-programming- (DP) based methods. Our primary contribution is a new algorithm for emulating the seeding and extension phases of BLAST. This operates in a single pass through a database at streaming rate, and with no preprocessing other than loading the query string. Moreover, it emulates parameters turned to maximum possible sensitivity with no slowdown. While current DP-based methods also operate at streaming rate, generating results can be cumbersome. We address this with a new structure for data extraction. We present results from several implementations showing order of magnitude acceleration over serial reference code. A simple extension assures compatibility with NCBI BLAST. PMID:19081828

Root gravitropism in maize and Arabidopsis

NASA Technical Reports Server (NTRS)

Evans, Michael L.

1993-01-01

Research during the period 1 March 1992 to 30 November 1993 focused on improvements in a video digitizer system designed to automate the recording of surface extension in plants responding to gravistimulation. The improvements included modification of software to allow detailed analysis of localized extension patterns in roots of Arabidopsis. We used the system to analyze the role of the postmitotic isodiametric growth zone (a region between the meristem and the elongation zone) in the response of maize roots to auxin, calcium, touch and gravity. We also used the system to analyze short-term auxin and gravitropic responses in mutants of Arabidopsis with reduced auxin sensitivity. In a related project, we studied the relationship between growth rate and surface electrical currents in roots by examining the effects of gravity and thigmostimulation on surface potentials in maize roots.

Constitutive BAK activation as a determinant of drug sensitivity in malignant lymphohematopoietic cells.

PubMed

Dai, Haiming; Ding, Husheng; Meng, X Wei; Peterson, Kevin L; Schneider, Paula A; Karp, Judith E; Kaufmann, Scott H

2015-10-15

Mitochondrial outer membrane permeabilization (MOMP), a key step in the intrinsic apoptotic pathway, is incompletely understood. Current models emphasize the role of BH3-only BCL2 family members in BAX and BAK activation. Here we demonstrate concentration-dependent BAK autoactivation under cell-free conditions and provide evidence that this autoactivation plays a key role in regulating the intrinsic apoptotic pathway in intact cells. In particular, we show that up to 80% of BAK (but not BAX) in lymphohematopoietic cell lines is oligomerized and bound to anti-apoptotic BCL2 family members in the absence of exogenous death stimuli. The extent of this constitutive BAK oligomerization is diminished by BAK knockdown and unaffected by BIM or PUMA down-regulation. Further analysis indicates that sensitivity of cells to BH3 mimetics reflects the identity of the anti-apoptotic proteins to which BAK is constitutively bound, with extensive BCLXL•BAK complexes predicting navitoclax sensitivity, and extensive MCL1•BAK complexes predicting A1210477 sensitivity. Moreover, high BAK expression correlates with sensitivity of clinical acute myelogenous leukemia to chemotherapy, whereas low BAK levels correlate with resistance and relapse. Collectively, these results inform current understanding of MOMP and provide new insight into the ability of BH3 mimetics to induce apoptosis without directly activating BAX or BAK. © 2015 Dai et al.; Published by Cold Spring Harbor Laboratory Press.

Prediction of redox-sensitive cysteines using sequential distance and other sequence-based features.

PubMed

Sun, Ming-An; Zhang, Qing; Wang, Yejun; Ge, Wei; Guo, Dianjing

2016-08-24

Reactive oxygen species can modify the structure and function of proteins and may also act as important signaling molecules in various cellular processes. Cysteine thiol groups of proteins are particularly susceptible to oxidation. Meanwhile, their reversible oxidation is of critical roles for redox regulation and signaling. Recently, several computational tools have been developed for predicting redox-sensitive cysteines; however, those methods either only focus on catalytic redox-sensitive cysteines in thiol oxidoreductases, or heavily depend on protein structural data, thus cannot be widely used. In this study, we analyzed various sequence-based features potentially related to cysteine redox-sensitivity, and identified three types of features for efficient computational prediction of redox-sensitive cysteines. These features are: sequential distance to the nearby cysteines, PSSM profile and predicted secondary structure of flanking residues. After further feature selection using SVM-RFE, we developed Redox-Sensitive Cysteine Predictor (RSCP), a SVM based classifier for redox-sensitive cysteine prediction using primary sequence only. Using 10-fold cross-validation on RSC758 dataset, the accuracy, sensitivity, specificity, MCC and AUC were estimated as 0.679, 0.602, 0.756, 0.362 and 0.727, respectively. When evaluated using 10-fold cross-validation with BALOSCTdb dataset which has structure information, the model achieved performance comparable to current structure-based method. Further validation using an independent dataset indicates it is robust and of relatively better accuracy for predicting redox-sensitive cysteines from non-enzyme proteins. In this study, we developed a sequence-based classifier for predicting redox-sensitive cysteines. The major advantage of this method is that it does not rely on protein structure data, which ensures more extensive application compared to other current implementations. Accurate prediction of redox-sensitive cysteines not only enhances our understanding about the redox sensitivity of cysteine, it may also complement the proteomics approach and facilitate further experimental investigation of important redox-sensitive cysteines.

Different orders of lives in the universe

NASA Astrophysics Data System (ADS)

Sikdar, M. K.

2014-08-01

In this article, main life sensitive elements involved in life creating processes on earth have been explored. An in-depth study has been made to search out material abundances of all life sensitive elements in the periodic table mainly on earth, celestial bodies like star, binary stars, extra-solar system, extra solar planets and galaxies etc. at large. Extensive review has been made to project how life processes are being triggered in our earth and intakes required for continuous metabolism, mutation, reproducibility etc. Finally on the basis of ideas developed about the life processes on earth, other life chains that may happen to exist on other celestial bodies have been predicted. The constraints and barriers that stand in the way of communications have also been pointed out.

Random mutagenesis screening indicates the absence of a separate H(+)-sensor in the pH-sensitive Kir channels.

PubMed

Paynter, Jennifer J; Shang, Lijun; Bollepalli, Murali K; Baukrowitz, Thomas; Tucker, Stephen J

2010-01-01

Several inwardly-rectifying (Kir) potassium channels (Kir1.1, Kir4.1 and Kir4.2) are characterised by their sensitivity to inhibition by intracellular H(+) within the physiological range. The mechanism by which these channels are regulated by intracellular pH has been the subject of intense scrutiny for over a decade, yet the molecular identity of the titratable pH-sensor remains elusive. In this study we have taken advantage of the acidic intracellular environment of S. cerevisiae and used a K(+) -auxotrophic strain to screen for mutants of Kir1.1 with impaired pH-sensitivity. In addition to the previously identified K80M mutation, this unbiased screening approach identified a novel mutation (S172T) in the second transmembrane domain (TM2) that also produces a marked reduction in pH-sensitivity through destabilization of the closed-state. However, despite this extensive mutagenic approach, no mutations could be identified which removed channel pH-sensitivity or which were likely to act as a separate H(+) -sensor unique to the pH-sensitive Kir channels. In order to explain these results we propose a model in which the pH-sensing mechanism is part of an intrinsic gating mechanism common to all Kir channels, not just the pH-sensitive Kir channels. In this model, mutations which disrupt this pH-sensor would result in an increase, not reduction, in pH-sensitivity. This has major implications for any future studies of Kir channel pH-sensitivity and explains why formal identification of these pH-sensing residues still represents a major challenge.

Simulation of ground-water flow of the coastal plain aquifers in parts of Maryland, Delaware, and the District of Columbia

USGS Publications Warehouse

Fleck, W.B.; Vroblesky, D.A.

1996-01-01

Geomorphic processes and the aquatic habitat of the Redwood Creek basin were studied extensively between 1973 and 1983. This volume contains 22 separate articles by 32 investigators who studied geology, major storms, timber harvesting and its role on accelerating erosion, mass movement, fluvial erosion, sediment transport and storage, stream channel response to storms and landuse, stream habitat, and stream chemistry. This research describes a rapidly eroding landscape that is sensitive to effects of both landuse and major storms.

Impediments and constraints in the uptake of water sensitive urban design measures in greenfield and infill developments.

PubMed

Sharma, Ashok K; Cook, Stephen; Tjandraatmadja, Grace; Gregory, Alan

2012-01-01

Water sensitive urban developments are designed with integrated urban water management concepts and water sensitive urban design measures. The initiatives that may be included are the substitution of imported drinking water with alternative sources using a fit-for-purpose approach and structural and non-structural measures for the source control of stormwater. A water sensitive approach to urban development can help in achieving sustainability objectives by minimising disturbance to ecological and hydrological processes, and also relieve stress on conventional water systems. Water sensitive urban developments remain novel in comparison with conventional approaches, so the understanding and knowledge of the systems in regards to their planning; design; implementation; operation and maintenance; health impacts and environmental impacts is still developing and thus the mainstream uptake of these approaches faces many challenges. A study has been conducted to understand these challenges through a detailed literature review, investigating a large number of local greenfield and infill developments, and conducting extensive consultation with water professionals. This research has identified the social, economic, political, institutional and technological challenges faced in implementing water sensitive urban design in greenfield and infill developments. The research found in particular that there is the need for long-term monitoring studies of water sensitive urban developments. This monitoring is important to validate the performance of novel approaches implemented and improve associated guidelines, standards, and regulatory and governance frameworks, which can lead to mainstream acceptance of water sensitive urban development approaches. The dissemination of this research will help generate awareness among water professionals, water utilities, developers, planners and regulators of the research challenges to be addressed in order to achieve more mainstream acceptance of water sensitive approaches to urban development. This study is based on existing water sensitive urban developments in Australia, however, the methodology adopted in investigating impediments to the uptake of these developments can be applied globally. It is hoped that insights from this study will benefit water professionals in other countries where there is also a move towards water sensitive urban development.

Dual-spin attitude control for outer planet missions

NASA Technical Reports Server (NTRS)

Ward, R. S.; Tauke, G. J.

1977-01-01

The applicability of dual-spin technology to a Jupiter orbiter with probe mission was investigated. Basic mission and system level attitude control requirements were established and preliminary mechanization and control concepts developed. A comprehensive 18-degree-of-freedom digital simulation was utilized extensively to establish control laws, study dynamic interactions, and determined key sensitivities. Fundamental system/subsystem constraints were identified, and the applicability of dual-spin technology to a Jupiter orbiter with probe mission was validated.

Restoration of gravitropic sensitivity in starch-deficient mutants of Arabidopsis by hypergravity

NASA Technical Reports Server (NTRS)

Fitzelle, K. J.; Kiss, J. Z.

2001-01-01

Despite the extensive study of plant gravitropism, there have been few experiments which have utilized hypergravity as a tool to investigate gravisensitivity in flowering plants. Previous studies have shown that starch-deficient mutants of Arabidopsis are less sensitive to gravity compared to the wild-type (WT). In this report, the question addressed was whether hypergravity could restore the sensitivity of starch-deficient mutants of Arabidopsis. The strains examined include a WT, a starchless mutant and a reduced-starch mutant. Vertical orientation studies with dark-grown seedlings indicate that increased centrifugal acceleration improves orientation relative to the acceleration vector for all strains, even the WT. For starchless roots, growth of seedlings under constant 5 g acceleration was required to restore orientation to the level of the WT at 1 g. In contrast, approximately 10 g was required to restore the orientation of the starchless mutant hypocotyls to a WT level at 1 g. Examination of plastid position in root cap columella cells of the starchless mutant revealed that the restoration of gravitropic sensitivity was correlated with the sedimentation of plastids toward the distal cell wall. Even in WT plants, hypergravity caused greater sedimentation of plastids and improved gravitropic capability. Collectively, these experiments support the hypothesis of a statolith-based system of gravity perception in plants. As far as is known, this is the first report to use hypergravity to study the mechanisms of gravitropism in Arabidopsis.

Evaluation of the bioNexia Legionella Test, Including Impact of Incubation Time Extension, for Detection of Legionella pneumophila Serogroup 1 Antigen in Urine.

PubMed

Badoux, Paul; Euser, Sjoerd M; Bruin, Jacob P; Mulder, Patrick P G; Yzerman, Ed P F

2017-06-01

In this study, we compared the bioNexia test (bioMérieux, Marcy-l'Étoile, France), a new immunochromatographic assay for the detection of Legionella pneumophila serogroup 1 in urine, with the BinaxNOW urinary antigen test (Alere, Waltham, Massachusetts, USA). After 15 min of incubation (in accordance with the manufacturers' instructions), the sensitivities and specificities were, respectively, 76.5% and 97.2% for the bioNexia test and 87.1% and 100% for the BinaxNOW test. After a prolonged incubation time of 60 min, the sensitivities and specificities increased to, respectively, 89.4% and 97.2% for the bioNexia test and 91.8% and 100% for the BinaxNOW test. When the tests were read after 15 min, the concentration of discrepant urine samples increased the sensitivities to 94.1% for both tests. In conclusion, we found that although the bioNexia test showed lower sensitivity for the detection of L. pneumophila antigen in nonconcentrated urine compared to the BinaxNOW test, a prolonged incubation time as well as the use of concentrated samples showed comparable sensitivities for both tests. Copyright © 2017 American Society for Microbiology.

A new framework for comprehensive, robust, and efficient global sensitivity analysis: 1. Theory

NASA Astrophysics Data System (ADS)

Razavi, Saman; Gupta, Hoshin V.

2016-01-01

Computer simulation models are continually growing in complexity with increasingly more factors to be identified. Sensitivity Analysis (SA) provides an essential means for understanding the role and importance of these factors in producing model responses. However, conventional approaches to SA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we present a new and general sensitivity analysis framework (called VARS), based on an analogy to "variogram analysis," that provides an intuitive and comprehensive characterization of sensitivity across the full spectrum of scales in the factor space. We prove, theoretically, that Morris (derivative-based) and Sobol (variance-based) methods and their extensions are special cases of VARS, and that their SA indices can be computed as by-products of the VARS framework. Synthetic functions that resemble actual model response surfaces are used to illustrate the concepts, and show VARS to be as much as two orders of magnitude more computationally efficient than the state-of-the-art Sobol approach. In a companion paper, we propose a practical implementation strategy, and demonstrate the effectiveness, efficiency, and reliability (robustness) of the VARS framework on real-data case studies.

Prospects for indirect dark matter searches with MeV photons

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

Bartels, Richard; Gaggero, Daniele; Weniger, Christoph, E-mail: r.t.bartels@uva.nl, E-mail: d.gaggero@uva.nl, E-mail: c.weniger@uva.nl

2017-05-01

Over the past decade, extensive studies have been undertaken to search for photon signals from dark matter annihilation or decay for dark matter particle masses above ∼1 GeV. However, due to the lacking sensitivity of current experiments at MeV–GeV energies, sometimes dubbed the 'MeV gap', dark matter models with MeV to sub-GeV particle masses have received little attention so far. Various proposed MeV missions (like, e.g., e-ASTROGAM or AMEGO) are aimed at closing this gap in the mid- or long-term future. This, and the absence of clear dark matter signals in the GeV–TeV range, makes it relevant to carefully reconsidermore » the expected experimental instrumental sensitivities in this mass range. The most common two-body annihilation channels for sub-GeV dark matter are to neutrinos, electrons, pions or directly to photons. Among these, only the electron channel has been extensively studied, and almost exclusively in the context of the 511 keV line. In this work, we study the prospects for detecting MeV dark matter annihilation in general in future MeV missions, using e-ASTROGAM as reference, and focusing on dark matter masses in the range 1 MeV–3 GeV. In the case of leptonic annihilation, we emphasise the importance of the often overlooked bremsstrahlung and in-flight annihilation spectral features, which in many cases provide the dominant gamma-ray signal in this regime.« less

DEVELOPMENT OF A PHYSIOLOGICALLY BASED PHARMACOKINETIC MODEL FOR ETHYLENE GLYCOL AND ITS MAJOR METABOLITE, GLYCOLIC ACID, IN RATS AND HUMANS

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

Corley, Rick A.; Bartels, M J.; Carney, E W.

2005-05-19

An extensive database on the toxicity and modes of action of the major industrial chemical, ethylene glycol (EG), has been developed over the past several decades. These studies have consistently identified the kidney as a primary target organ, with rats being more sensitive than mice and males more sensitive than females following chronic exposure. Renal toxicity has been associated with the terminal metabolite, oxalic acid which can precipitate with calcium to form crystals. EG also induces developmental toxicity, although these effects appear to require high-doses or accelerated dose-rates, and have been reported only in rats and mice. The developmental toxicitymore » of EG has been attributed to the intermediate metabolite, glycolic acid (GA). The developmental toxicity of EG has been the subject of extensive research and regulatory review in recent years. Therefore, a physiologically based pharmacokinetic (PBPK) model was developed to integrate the extensive mode of action and pharmacokinetic data on EG and GA for use in developmental risk assessment. Metabolic rate constants and partition coefficients for EG and GA were estimated from in vitro studies. Other biochemical constants were optimized from appropriate in vivo pharmacokinetic studies. The resulting PBPK model includes inhalation, oral, dermal, intravenous and subcutaneous routes of administration. Metabolism of EG and GA were described in the liver with elimination via the kidneys. Several rat and human metabolism studies were used to validate the resulting PBPK model. Consistent with these studies, simulations indicated that the metabolism of EG to GA was essentially first-order (linear) up to 2500 mg/kg/day while the metabolism of GA saturated between bolus ethylene glycol doses of 200 and 1000 mg/kg/day. This saturation results in non-linear increases in blood GA concentrations, correlating with the developmental toxicity of EG. Pregnancy had no effect on maternal EG and GA kinetics over a broad dose range. The human PBPK model was validated against a large database of human clinical case reports in a companion study (Corley and McMartin, 2004) where the impacts of treatment and a comparison of internal dose surrogates for human health risk assessments were conducted.« less

Modic Type 1 Changes: Detection Performance of Fat-Suppressed Fluid-Sensitive MRI Sequences.

PubMed

Finkenstaedt, Tim; Del Grande, Filippo; Bolog, Nicolae; Ulrich, Nils; Tok, Sina; Kolokythas, Orpheus; Steurer, Johann; Andreisek, Gustav; Winklhofer, Sebastian

2018-02-01

 To assess the performance of fat-suppressed fluid-sensitive MRI sequences compared to T1-weighted (T1w) / T2w sequences for the detection of Modic 1 end-plate changes on lumbar spine MRI.  Sagittal T1w, T2w, and fat-suppressed fluid-sensitive MRI images of 100 consecutive patients (consequently 500 vertebral segments; 52 female, mean age 74 ± 7.4 years; 48 male, mean age 71 ± 6.3 years) were retrospectively evaluated. We recorded the presence (yes/no) and extension (i. e., Likert-scale of height, volume, and end-plate extension) of Modic I changes in T1w/T2w sequences and compared the results to fat-suppressed fluid-sensitive sequences (McNemar/Wilcoxon-signed-rank test).  Fat-suppressed fluid-sensitive sequences revealed significantly more Modic I changes compared to T1w/T2w sequences (156 vs. 93 segments, respectively; p < 0.001). The extension of Modic I changes in fat-suppressed fluid-sensitive sequences was significantly larger compared to T1w/T2w sequences (height: 2.53 ± 0.82 vs. 2.27 ± 0.79, volume: 2.35 ± 0.76 vs. 2.1 ± 0.65, end-plate: 2.46 ± 0.76 vs. 2.19 ± 0.81), (p < 0.05). Modic I changes that were only visible in fat-suppressed fluid-sensitive sequences but not in T1w/T2w sequences were significantly smaller compared to Modic I changes that were also visible in T1w/T2w sequences (p < 0.05).  In conclusion, fat-suppressed fluid-sensitive MRI sequences revealed significantly more Modic I end-plate changes and demonstrated a greater extent compared to standard T1w/T2w imaging.   · When the Modic classification was defined in 1988, T2w sequences were heavily T2-weighted and thus virtually fat-suppressed.. · Nowadays, the bright fat signal in T2w images masks edema-like changes.. · The conventional definition of Modic I changes is not fully applicable anymore.. · Fat-suppressed fluid-sensitive MRI sequences revealed more/greater extent of Modic I changes.. · Finkenstaedt T, Del Grande F, Bolog N et al. Modic Type 1 Changes: Detection Performance of Fat-Suppressed Fluid-Sensitive MRI Sequences. Fortschr Röntgenstr 2018; 190: 152 - 160. © Georg Thieme Verlag KG Stuttgart · New York.

The Intelligent System of Cardiovascular Disease Diagnosis Based on Extension Data Mining

NASA Astrophysics Data System (ADS)

Sun, Baiqing; Li, Yange; Zhang, Lin

This thesis gives the general definition of the concepts of extension knowledge, extension data mining and extension data mining theorem in high dimension space, and also builds the IDSS integrated system by the rough set, expert system and neural network, develops the relevant computer software. From the diagnosis tests, according to the common diseases of myocardial infarctions, angina pectoris and hypertension, and made the test result with physicians, the results shows that the sensitivity, specific and accuracy diagnosis by the IDSS are all higher than the physicians. It can improve the rate of the accuracy diagnosis of physician with the auxiliary help of this system, which have the obvious meaning in low the mortality, disability rate and high the survival rate, and has strong practical values and further social benefits.

The thermal aggregation of ovalbumin as large particles decreases its allergenicity for egg allergic patients and in a murine model.

PubMed

Claude, M; Lupi, R; Bouchaud, G; Bodinier, M; Brossard, C; Denery-Papini, S

2016-07-15

Most egg-allergic children can tolerate extensively cooked eggs. Ovalbumin, a major allergen in egg whites, is prone to aggregate upon heating. This study compares ovalbumin's allergenicity when it is aggregated as large particles to ovalbumin in its native form. Immunoglobulins (Ig)-binding and the degranulation capacities of native and aggregated ovalbumin were measured with sera from egg-allergic children and from mice sensitized to native or aggregated ovalbumin. The influence of ovalbumin structure on Ig production upon sensitization and elicitation potency by challenge was also studied. We showed that heat aggregation of ovalbumin as large particles enhances IgG production and promotes IgG2a production (a shift toward the T helper 1 profile). Aggregated ovalbumin displayed lower Ig-binding and basophil-activation capacities for sera from both allergic patients and mice. This work illustrates the links between ovalbumin structure after heating and allergenicity potential using parameters from both the sensitization and elicitation phases of the allergic reaction. Copyright © 2016 Elsevier Ltd. All rights reserved.

Confidence interval estimation of the difference between two sensitivities to the early disease stage.

PubMed

Dong, Tuochuan; Kang, Le; Hutson, Alan; Xiong, Chengjie; Tian, Lili

2014-03-01

Although most of the statistical methods for diagnostic studies focus on disease processes with binary disease status, many diseases can be naturally classified into three ordinal diagnostic categories, that is normal, early stage, and fully diseased. For such diseases, the volume under the ROC surface (VUS) is the most commonly used index of diagnostic accuracy. Because the early disease stage is most likely the optimal time window for therapeutic intervention, the sensitivity to the early diseased stage has been suggested as another diagnostic measure. For the purpose of comparing the diagnostic abilities on early disease detection between two markers, it is of interest to estimate the confidence interval of the difference between sensitivities to the early diseased stage. In this paper, we present both parametric and non-parametric methods for this purpose. An extensive simulation study is carried out for a variety of settings for the purpose of evaluating and comparing the performance of the proposed methods. A real example of Alzheimer's disease (AD) is analyzed using the proposed approaches. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impact of variation in the BDNF gene on social stress sensitivity and the buffering impact of positive emotions: replication and extension of a gene-environment interaction.

PubMed

van Winkel, Mark; Peeters, Frenk; van Winkel, Ruud; Kenis, Gunter; Collip, Dina; Geschwind, Nicole; Jacobs, Nele; Derom, Catherine; Thiery, Evert; van Os, Jim; Myin-Germeys, Inez; Wichers, Marieke

2014-06-01

A previous study reported that social stress sensitivity is moderated by the brain-derived-neurotrophic-factor(Val66Met) (BDNF rs6265) genotype. Additionally, positive emotions partially neutralize this moderating effect. The current study aimed to: (i) replicate in a new independent sample of subjects with residual depressive symptoms the moderating effect of BDNF(Val66Met) genotype on social stress sensitivity, (ii) replicate the neutralizing impact of positive emotions, (iii) extend these analyses to other variations in the BDNF gene in the new independent sample and the original sample of non-depressed individuals. Previous findings were replicated in an experience sampling method (ESM) study. Negative Affect (NA) responses to social stress were stronger in "Val/Met" carriers of BDNF(Val66Met) compared to "Val/Val" carriers. Positive emotions neutralized the moderating effect of BDNF(Val66Met) genotype on social stress sensitivity in a dose-response fashion. Finally, two of four additional BDNF SNPs (rs11030101, rs2049046) showed similar moderating effects on social stress-sensitivity across both samples. The neutralizing effect of positive emotions on the moderating effects of these two additional SNPs was found in one sample. In conclusion, ESM has important advantages in gene-environment (GxE) research and may attribute to more consistent findings in future GxE research. This study shows how the impact of BDNF genetic variation on depressive symptoms may be explained by its impact on subtle daily life responses to social stress. Further, it shows that the generation of positive affect (PA) can buffer social stress sensitivity and partially undo the genetic susceptibility. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

Single mode variable-sensitivity fiber optic sensors

NASA Technical Reports Server (NTRS)

Murphy, K. A.; Fogg, B. R.; Gunther, M. F.; Claus, R. O.

1992-01-01

We review spatially-weighted optical fiber sensors that filter specific vibration modes from one dimensional beams placed in clamped-free and clamped-clamped configurations. The sensitivity of the sensor is varied along the length of the fiber by tapering circular-core, dual-mode optical fibers. Selective vibration mode suppression on the order of 10 dB was obtained. We describe experimental results and propose future extensions to single mode sensor applications.

JPL Contamination Control Engineering

NASA Technical Reports Server (NTRS)

Blakkolb, Brian

2013-01-01

JPL has extensive expertise fielding contamination sensitive missions-in house and with our NASA/industry/academic partners.t Development and implementation of performance-driven cleanliness requirements for a wide range missions and payloads - UV-Vis-IR: GALEX, Dawn, Juno, WFPC-II, AIRS, TES, et al - Propulsion, thermal control, robotic sample acquisition systems. Contamination control engineering across the mission life cycle: - System and payload requirements derivation, analysis, and contamination control implementation plans - Hardware Design, Risk trades, Requirements V-V - Assembly, Integration & Test planning and implementation - Launch site operations and launch vehicle/payload integration - Flight ops center dot Personnel on staff have expertise with space materials development and flight experiments. JPL has capabilities and expertise to successfully address contamination issues presented by space and habitable environments. JPL has extensive experience fielding and managing contamination sensitive missions. Excellent working relationship with the aerospace contamination control engineering community/.

Validation and subsequent development of the DEREK skin sensitization rulebase by analysis of the BgVV list of contact allergens.

PubMed

Barratt, M D; Langowski, J J

1999-01-01

The DEREK knowledge-based computer system contains a subset of approximately 50 rules describing chemical substructures (toxophores) responsible for skin sensitization. This rulebase, based originally on Unilever historical in-house guinea pig maximization test data, has been subject to extensive validation and is undergoing refinement as the next stage of its development. As part of an ongoing program of validation and testing, the predictive ability of the sensitization rule set has been assessed by processing the structures of the 84 chemical substances in the list of contact allergens issued by the BgVV (German Federal Institute for Health Protection of Consumers). This list of chemicals is important because the biological data for each of the chemicals have been carefully scrutinized and peer reviewed, a key consideration in an area of toxicology in which much unreliable and potentially misleading data have been published. The existing DEREK rulebase for skin sensitization identified toxophores for skin sensitization in the structures of 71 out of the 84 chemicals (85%). The exercise highlighted areas of chemistry where further development of the rulebase was required, either by extension of the scope of existing rules or by generation of new rules where a sound mechanistic rationale for the biological activity could be established. Chemicals likely to be acting as photoallergens were identified, and new rules for photoallergenicity have subsequently been written. At the end of the exercise, the refined rulebase was able to identify toxophores for skin sensitization for 82 of the 84 chemicals in the BgVV list.

New Uses for Sensitivity Analysis: How Different Movement Tasks Effect Limb Model Parameter Sensitivity

NASA Technical Reports Server (NTRS)

Winters, J. M.; Stark, L.

1984-01-01

Original results for a newly developed eight-order nonlinear limb antagonistic muscle model of elbow flexion and extension are presented. A wider variety of sensitivity analysis techniques are used and a systematic protocol is established that shows how the different methods can be used efficiently to complement one another for maximum insight into model sensitivity. It is explicitly shown how the sensitivity of output behaviors to model parameters is a function of the controller input sequence, i.e., of the movement task. When the task is changed (for instance, from an input sequence that results in the usual fast movement task to a slower movement that may also involve external loading, etc.) the set of parameters with high sensitivity will in general also change. Such task-specific use of sensitivity analysis techniques identifies the set of parameters most important for a given task, and even suggests task-specific model reduction possibilities.

Diagnostic sensitivity and specificity of a participatory disease surveillance method for highly pathogenic avian influenza in household chicken flocks in Indonesia.

PubMed

Robyn, M; Priyono, W B; Kim, L M; Brum, E

2012-06-01

A study was conducted to assess the diagnostic sensitivity and specificity of a disease surveillance method for diagnosis of highly pathogenic avian influenza (HPAI) outbreaks in household chicken flocks used by participatory disease surveillance (PDS) teams in Yogyakarta Province, Indonesia. The Government of Indonesia, in partnership with the Food and Agriculture Organization of the United Nations, has implemented a PDS method for the detection of HPAI outbreaks in poultry since 2006. The PDS method in Indonesia utilizes both a clinical case definition (CD) and the result of a commercial rapid antigen test kit Yogyakarta 55611, to diagnose HPAI outbreaks, primarily in backyard chicken flocks. The following diagnostic sensitivities and specificities were obtained relative to real-time reverse transcription-PCR as the gold standard diagnostic test: 1) 89% sensitivity (CI95: 75%-97%) and 96% specificity (CI95: 89%-99%) for the PDS CD alone; 2) 86% sensitivity (CI95: 71%-95%) and 99% specificity (CI95: 94%-100%) for the rapid antigen test alone; and 3) 84% sensitivity (CI95: 68%-94%) and 100% specificity (CI95: 96%-100%) for the PDS CD result combined with the rapid antigen test result. Based on these results, HPAI outbreaks in extensively raised household chickens can be diagnosed with sufficient sensitivity and specificity using the PDS method as implemented in Indonesia. Subject to further field evaluation, data from this study suggest that the diagnostic sensitivity of the PDS method may be improved by expanding the PDS CD to include more possible clinical presentations of HPAI and by increasing the number of rapid antigen tests to three different birds with HPAI-compatible signs of same flock.

Acute toxicity assessment of Polish (waste) water with a microplate-based Hydra attenuata assay: a comparison with the Microtox test.

PubMed

Pardos, M; Benninghoff, C; Guéguen, C; Thomas, R; Dobrowolski, J; Dominik, J

1999-12-15

The use of Hydra attenuata in acute toxicity assessment is a potentially useful tool in (waste) water biomonitoring. The purpose of this study was to compare the sensitivity of H. attenuata with the extensively used Microtox test on 14 (waste) water samples from the Kraków region (South Poland). To this end, specific morphological changes displayed by the freshwater cnidarian Hydra attenuata (lethal LC50s and sublethal EC50s effects) and bioluminescence of the marine bacteria Vibrio fisheri (Microtox) were compared. Clearly, the Hydra assay was the more sensitive indicator of toxicity. No relationship was found among Hydra toxicological responses and water levels of As, Cd, Co, Cu, Pb and Zn. However, it appeared that toxicity to Hydra might be due to ammonia levels. Additional studies to better circumscribe the tolerance of H. attenuata to 'natural' water characteristics are needed.

Additional EIPC Study Analysis: Interim Report on High Priority Topics

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

Hadley, Stanton W

Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations weremore » developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 13 topics was developed for further analysis; this paper discusses the first five.« less

SERS-based pesticide detection by using nanofinger sensors

NASA Astrophysics Data System (ADS)

Kim, Ansoon; Barcelo, Steven J.; Li, Zhiyong

2015-01-01

Simple, sensitive, and rapid detection of trace levels of extensively used and highly toxic pesticides are in urgent demand for public health. Surface-enhanced Raman scattering (SERS)-based sensor was designed to achieve ultrasensitive and simple pesticide sensing. We developed a portable sensor system composed of high performance and reliable gold nanofinger sensor strips and a custom-built portable Raman spectrometer. Compared to the general procedure and previously reported studies that are limited to laboratory settings, our analytical method is simple, sensitive, rapid, and cost-effective. Based on the SERS results, the chemical interaction of two pesticides, chlorpyrifos (CPF) and thiabendazole (TBZ), with gold nanofingers was studied to determine a fingerprint for each pesticide. The portable SERS-sensor system was successfully demonstrated to detect CPF and TBZ pesticides within 15 min with a detection limit of 35 ppt in drinking water and 7 ppb on apple skin, respectively.

Impact of green roofs on stormwater quality in a South Australian urban environment.

PubMed

Razzaghmanesh, M; Beecham, S; Kazemi, F

2014-02-01

Green roofs are an increasingly important component of water sensitive urban design systems and can potentially improve the quality of urban runoff. However, there is evidence that they can occasionally act as a source rather than a sink for pollutants. In this study, the water quality of the outflow from both intensive and extensive green roof systems were studied in the city of Adelaide, South Australia over a period of nine months. The aim was to examine the effects of different green roof configurations on stormwater quality and to compare this with runoff from aluminium and asphalt roofs as control surfaces. The contaminant concentrations in runoff from both intensive and extensive green roofs generally decreased during the study period. A comparison between the two types of green roof showed that except for some events for EC, TDS and chloride, the values of the parameters such as pH, turbidity, nitrate, phosphate and potassium in intensive green roof outflows were higher than in the outflows from the extensive green roofs. These concentrations were compared to local, state, national and international water quality guidelines in order to investigate the potential for outflow runoff from green roofs to be reused for potable and non-potable purposes. The study found that green roof outflow can provide an alternative water source for non-potable purposes such as urban landscape irrigation and toilet flushing. © 2013.

The ANTARES optical module

NASA Astrophysics Data System (ADS)

ANTARES Collaboration; Amram, P.; Anghinolfi, M.; Anvar, S.; Ardellier-Desages, F. E.; Aslanides, E.; Aubert, J.-J.; Azoulay, R.; Bailey, D.; Basa, S.; Battaglieri, M.; Bellotti, R.; Benhammou, Y.; Bernard, F.; Berthier, R.; Bertin, V.; Billault, M.; Blaes, R.; Bland, R. W.; Blondeau, F.; de Botton, N.; Boulesteix, J.; Brooks, C. B.; Brunner, J.; Cafagna, F.; Calzas, A.; Capone, A.; Caponetto, L.; Cârloganu, C.; Carmona, E.; Carr, J.; Carton, P.-H.; Cartwright, S. L.; Cassol, F.; Cecchini, S.; Ciacio, F.; Circella, M.; Compère, C.; Cooper, S.; Coyle, P.; Croquette, J.; Cuneo, S.; Danilov, M.; van Dantzig, R.; De Marzo, C.; DeVita, R.; Deck, P.; Destelle, J.-J.; Dispau, G.; Drougou, J. F.; Druillole, F.; Engelen, J.; Feinstein, F.; Festy, D.; Fopma, J.; Gallone, J.-M.; Giacomelli, G.; Goret, P.; Gosset, L.; Gournay, J.-F.; Heijboer, A.; Hernández-Rey, J. J.; Herrouin, G.; Hubbard, J. R.; Jaquet, M.; de Jong, M.; Karolak, M.; Kooijman, P.; Kouchner, A.; Kudryavtsev, V. A.; Lachartre, D.; Lafoux, H.; Lamare, P.; Languillat, J.-C.; Laubier, L.; Laugier, J.-P.; Le Guen, Y.; Le Provost, H.; Le Van Suu, A.; Lemoine, L.; Lo Nigro, L.; Lo Presti, D.; Loucatos, S.; Louis, F.; Lyashuk, V.; Magnier, P.; Marcelin, M.; Margiotta, A.; Massol, A.; Masullo, R.; Mazéas, F.; Mazeau, B.; Mazure, A.; McMillan, J. E.; Michel, J. L.; Migneco, E.; Millot, C.; Mols, P.; Montanet, F.; Montaruli, T.; Morel, J. P.; Moscoso, L.; Musumeci, M.; Navas, S.; Nezri, E.; Nooren, G. J.; Oberski, J.; Olivetto, C.; Oppelt-Pohl, A.; Palanque-Delabrouille, N.; Papaleo, R.; Payre, P.; Perrin, P.; Petruccetti, M.; Petta, C.; Piattelli, P.; Poinsignon, J.; Potheau, R.; Queinec, Y.; Racca, C.; Raia, G.; Randazzo, N.; Rethore, F.; Riccobene, G.; Ricol, J.-S.; Ripani, M.; Roca-Blay, V.; Rolin, J. F.; Rostovstev, A.; Russo, G. V.; Sacquin, Y.; Salusti, E.; Schuller, J.-P.; Schuster, W.; Soirat, J.-P.; Souvorova, O.; Spooner, N. J. C.; Spurio, M.; Stolarczyk, T.; Stubert, D.; Taiuti, M.; Tao, C.; Tayalati, Y.; Thompson, L. F.; Tilav, S.; Triay, R.; Valente, V.; Varlamov, I.; Vaudaine, G.; Vernin, P.; de Witt Huberts, P.; de Wolf, E.; Zakharov, V.; Zavatarelli, S.; de D. Zornoza, J.; Zún~iga, J.

2002-05-01

The ANTARES collaboration is building a deep sea neutrino telescope in the Mediterranean Sea. This detector will cover a sensitive area of typically 0.1km2 and will be equipped with about 1000 optical modules. Each of these optical modules consists of a large area photomultiplier and its associated electronics housed in a pressure resistant glass sphere. The design of the ANTARES optical module, which is a key element of the detector, has been finalized following extensive R&D studies and is reviewed here in detail.

Peanut lipids display potential adjuvanticity by triggering a pro-inflammatory response in human keratinocytes.

PubMed

Palladino, C; Narzt, M S; Bublin, M; Schreiner, M; Humeniuk, P; Gschwandtner, M; Hafner, C; Hemmer, W; Hoffmann-Sommergruber, K; Mildner, M; Palomares, O; Gruber, F; Breiteneder, H

2018-05-10

Currently, the earliest cellular and molecular signals driving allergic sensitization to peanuts are not fully understood, even though peanut allergens have been studied extensively. Meanwhile, lipids contained within allergen sources are emerging as players in the pathogenesis of allergies. Exposure of infants to peanut oil-containing lotions was described as a risk factor for the development of peanut allergy (1). This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Cross-sensitization to Artemisia and Ambrosia pollen allergens in an area located outside of the current distribution range of Ambrosia.

PubMed

Grewling, Łukasz; Jenerowicz, Dorota; Bogawski, Paweł; Smith, Matt; Nowak, Małgorzata; Frątczak, Agata; Czarnecka-Operacz, Magdalena

2018-02-01

The role of long-distance transported (LDT) Ambrosia pollen in inducing new sensitization and affecting sensitization rates in Artemisia -sensitized patients is unclear. The aim of this study was to estimate the degree of cross-sensitization to Ambrosia/Artemisi a allergens in citizens of Poznan (Western Poland). This area is covered by extensive Artemisia populations but does not currently have local Ambrosia populations. Sera of 119 patients were tested by fluoroenzyme immunoassay (CAP-FEIA system) against pollen allergen extracts of Artemisia vulgaris and Ambrosia artemisiifolia , an allergenic component of A. vulgaris ( nArt v 1 ), and an allergenic component of A. artemisiifolia ( nAmb a 1 ). Skin prick tests (SPTs, n = 86) were performed with pollen allergen extracts of A. vulgaris and A. artemisiifolia . Artemisia and Ambrosia pollen in ambient air was collected (1996-2013) by a Hirst type volumetric trap sited at roof level (33 m). The SPT showed that the prevalence of sensitization to Ambrosia and Artemisia pollen exceeded 3.5%, and 10.5%, respectively. The measurements of IgE in blood serum (CAP-FEIA) revealed that among Ambrosia -sensitized patients 90.1% (20/22 patients) were concomitantly sensitized to Artemisia . 59.1% (13/22) of these patients reacted to nArt v 1 , suggesting primary sensitization to Artemisia pollen. Only 2 (9.1%) patients were mono-sensitized to Ambrosia pollen extract, but surprisingly not to nAmb a 1 . The LDT Ambrosia pollen had a negligible effect on the rate of sensitization to Ambrosia allergens in Poznan and did not increase the prevalence of sensitization to Artemisia pollen in this region. However, the majority of patients showing hypersensitization to Artemisia pollen might also present symptoms during elevated episodes of LDT of Ambrosia pollen.

Imaging infection with 18F-FDG-labeled leukocyte PET/CT: initial experience in 21 patients.

PubMed

Dumarey, Nicolas; Egrise, Dominique; Blocklet, Didier; Stallenberg, Bernard; Remmelink, Myriam; del Marmol, Véronique; Van Simaeys, Gaëtan; Jacobs, Frédérique; Goldman, Serge

2006-04-01

The aim of this study was to assess the feasibility and the potential role of PET/CT with (18)F-FDG-labeled autologous leukocytes in the diagnosis and localization of infectious lesions. Twenty-one consecutive patients with suspected or documented infection were prospectively evaluated with whole-body PET/CT 3 h after injection of autologous (18)F-FDG-labeled leukocytes. Two experienced nuclear medicine physicians who were unaware of the clinical end-diagnosis reviewed all PET/CT studies. A visual score (0-3)-according to uptake intensity-was used to assess studies. The results of PET/CT with (18)F-FDG-labeled white blood cell ((18)F-FDG-WBC) assessment were compared with histologic or biologic diagnosis in 15 patients and with clinical end-diagnosis after complete clinical work-up in 6 patients. Nine patients had fever of unknown etiology, 6 patients had documented infection but with unknown extension of the infectious disease, 4 patients had a documented infection with unfavorable evolution, and 2 patients had a documented infection with known extension. The best trade-off between sensitivity and specificity was obtained when a visual score of >or=2 was chosen to identify increased tracer uptake as infection. With this threshold, sensitivity, specificity, and accuracy were each 86% on a patient-per-patient basis and 91%, 85%, and 90% on a lesion-per-lesion basis. In this small group of patients, the absence of areas with increased WBC uptake on WBC PET/CT had a 100% negative predictive value. Hybrid (18)F-FDG-WBC PET/CT was found to have a high sensitivity and specificity for the diagnosis of infection. It located infectious lesions with a high precision. In this small series, absence of areas with increased uptake virtually ruled out the presence of infection. (18)F-FDG-WBC PET/CT for infection detection deserves further investigation in a larger prospective series.

Primary mass discrimination of high energy cosmic rays using PNN and k-NN methods

NASA Astrophysics Data System (ADS)

Rastegarzadeh, G.; Nemati, M.

2018-02-01

Probabilistic neural network (PNN) and k-Nearest Neighbors (k-NN) methods are widely used data classification techniques. In this paper, these two methods have been used to classify the Extensive Air Shower (EAS) data sets which were simulated using the CORSIKA code for three primary cosmic rays. The primaries are proton, oxygen and iron nuclei at energies of 100 TeV-10 PeV. This study is performed in the following of the investigations into the primary cosmic ray mass sensitive observables. We propose a new approach for measuring the mass sensitive observables of EAS in order to improve the primary mass separation. In this work, the EAS observables measurement has performed locally instead of total measurements. Also the relationships between the included number of observables in the classification methods and the prediction accuracy have been investigated. We have shown that the local measurements and inclusion of more mass sensitive observables in the classification processes can improve the classifying quality and also we have shown that muons and electrons energy density can be considered as primary mass sensitive observables in primary mass classification. Also it must be noted that this study is performed for Tehran observation level without considering the details of any certain EAS detection array.

Coupled excitable Ras and F-actin activation mediates spontaneous pseudopod formation and directed cell movement

PubMed Central

van Haastert, Peter J. M.; Keizer-Gunnink, Ineke; Kortholt, Arjan

2017-01-01

Many eukaryotic cells regulate their mobility by external cues. Genetic studies have identified >100 components that participate in chemotaxis, which hinders the identification of the conceptual framework of how cells sense and respond to shallow chemical gradients. The activation of Ras occurs during basal locomotion and is an essential connector between receptor and cytoskeleton during chemotaxis. Using a sensitive assay for activated Ras, we show here that activation of Ras and F-actin forms two excitable systems that are coupled through mutual positive feedback and memory. This coupled excitable system leads to short-lived patches of activated Ras and associated F-actin that precede the extension of protrusions. In buffer, excitability starts frequently with Ras activation in the back/side of the cell or with F-actin in the front of the cell. In a shallow gradient of chemoattractant, local Ras activation triggers full excitation of Ras and subsequently F-actin at the side of the cell facing the chemoattractant, leading to directed pseudopod extension and chemotaxis. A computational model shows that the coupled excitable Ras/F-actin system forms the driving heart for the ordered-stochastic extension of pseudopods in buffer and for efficient directional extension of pseudopods in chemotactic gradients. PMID:28148648

Association of oxidative status and insulin sensitivity in periparturient dairy cattle: an observational study.

PubMed

Abuelo, A; Hernández, J; Benedito, J L; Castillo, C

2016-04-01

Post-parturient insulin resistance (IR) is a common feature in all mammalian animals. However, in dairy cows, it can be exacerbated because of high milk yield, leading to excessive negative energy balance, which is related with increased disease incidence, reduced milk production and worsened reproductive performance. IR has been extensively investigated in humans suffering from diabetes mellitus. In these subjects, it is known that oxidative stress (OS) plays a causative role in the onset of IR. Although OS occurs in transitional dairy cattle, there are yet no studies that investigated the association between IR and OS in dairy cattle. Therefore, the aim of this study was to investigate whether there is a relationship between OS and IR in dairy cattle. Serum samples were taken repeatedly from 22 dairy cows from 2 months prior to the expected calving date to 2 months after calving and were analysed for markers of metabolic and redox balance. Surrogate indices of insulin sensitivity were also calculated. Generalised linear mixed models revealed an effect of the oxidative status on peripheral insulin concentration and on indices of insulin sensitivity. Hence, field trials should investigate the effectiveness of antioxidant therapy on insulin sensitivity in peripheral tissues during the transition period of dairy cattle. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

The evaluation and validation of Phadebas® paper as a presumptive screening tool for saliva on forensic exhibits.

PubMed

Wornes, Danielle J; Speers, Samuel J; Murakami, Julie A

2018-07-01

The Phadebas ® Forensic Press Test is routinely used for the detection of saliva. However, assessment of the use of Phadebas ® paper for this purpose has not been studied extensively. The suitability of Phadebas ® paper as a presumptive screening tool for saliva on forensic exhibits, was investigated by analysing the following: (1) sensitivity, (2) specificity, (3) effects of temperature on sensitivity and specificity, (4) detection of saliva in mixed body fluid samples, and (5) influence of substrate porosity. The results of this study demonstrated that Phadebas ® paper is more sensitive to α-amylase activity and less specific for saliva than previously reported. The use of an examination temperature of 37°C had no effect on sensitivity, but increased the incidence of cross-reactivity with other forensically relevant body fluid stains. Blood, urine and vaginal secretions can inhibit the detection of α-amylase activity with Phadebas ® paper in mixed stains of saliva and body fluid. Substrate porosity is a weak predictor for the time taken for a saliva stain to achieve a strong positive result on Phadebas ® paper. Overall, this study demonstrated that the Phadebas ® Forensic Press Test has limitations as a presumptive test for the accurate identification of saliva. Copyright © 2018 Elsevier B.V. All rights reserved.

Design Approaches for Enhancing Photovoltaic Performance of Silicon Solar Cells Sensitized by Proximal Nanocrystalline Quantum Dots

NASA Astrophysics Data System (ADS)

Shafiq, Natis

Energy transfer (ET) based sensitization of silicon (Si) using proximal nanocrystal quantum dots (NQDs) has been studied extensively in recent years as a means to develop thin and flexible Si based solar cells. The driving force for this research activity is a reduction in materials cost. To date, the main method for determining the role of ET in sensitizing Si has been optical spectroscopic studies. The quantitative contribution from two modes of ET (namely, nonradiative and radiative) has been reported using time-resolved photoluminescence (TRPL) spectroscopy coupled with extensive theoretical modelling. Thus, optical techniques have established the potential for utilizing ET based sensitization of Si as a feasible way to develop novel NQD-Si hybrid solar cells. However, the ultimate measure of the efficiency of ET-based mechanisms is the generation of electron-hole pairs by the impinging photons. It is therefore important to perform electrical measurements. However, only a couple of studies have attempted electrical quantification of ET modes. A few studies have focused on photocurrent measurements, without considering industrially relevant photovoltaic (PV) systems. Therefore, there is a need to develop a systematic approach for the electrical quantification of ET-generated charges and to help engineer new PV architectures optimized for harnessing the full advantages of ET mechanisms. Within this context, the work presented in this dissertation aims to develop an experimental testing protocol that can be applied to different PV structures for quantifying ET contributions from electrical measurements. We fabricated bulk Si solar cells (SCs) as a test structure and utilized CdSe/ZnS NQDs for ET based sensitization. The NQD-bulk Si hybrid devices showed ˜30% PV enhancement after NQD deposition. We measured external quantum efficiency (EQE) of these devices to quantify ET-generated charges. Reflectance measurements were also performed to decouple contributions of intrinsic optical effects (i.e., anti-reflection) from NQD mediated ET processes. Our analysis indicates that the contribution of ET-generated charges cannot be detected by EQE measurements. Instead, changes in the optical properties (i.e., anti-reflection property) due to the NQD layer are found to be the primary source of the photocurrent enhancement. Based on this finding, we propose to minimize bulk Si absorption by using an ultrathin (˜300 nm) Si PV architecture which should enable measurements of ET-generated charges. We describe an optimized process flow for fabricating such ultrathin Si devices. The devices fabricated by this method behave like photo-detectors and show enhanced sensitivity under 1 Sun AM1.5G illumination. The geometry and process flow of these devices make it possible to incorporate NQDs for sensitization. Overall, this dissertation provides a protocol for the quantification of ET-generated charges and documents an optimized process flow for the development of an ultrathin Si solar cells.

Domain decomposition for aerodynamic and aeroacoustic analyses, and optimization

NASA Technical Reports Server (NTRS)

Baysal, Oktay

1995-01-01

The overarching theme was the domain decomposition, which intended to improve the numerical solution technique for the partial differential equations at hand; in the present study, those that governed either the fluid flow, or the aeroacoustic wave propagation, or the sensitivity analysis for a gradient-based optimization. The role of the domain decomposition extended beyond the original impetus of discretizing geometrical complex regions or writing modular software for distributed-hardware computers. It induced function-space decompositions and operator decompositions that offered the valuable property of near independence of operator evaluation tasks. The objectives have gravitated about the extensions and implementations of either the previously developed or concurrently being developed methodologies: (1) aerodynamic sensitivity analysis with domain decomposition (SADD); (2) computational aeroacoustics of cavities; and (3) dynamic, multibody computational fluid dynamics using unstructured meshes.

A study of the stress wave factor technique for nondestructive evaluation of composite materials

NASA Technical Reports Server (NTRS)

Sarrafzadeh-Khoee, A.; Kiernan, M. T.; Duke, J. C., Jr.; Henneke, E. G., II

1986-01-01

The acousto-ultrasonic method of nondestructive evaluation is an extremely sensitive means of assessing material response. Efforts continue to complete the understanding of this method. In order to achieve the full sensitivity of the technique, extreme care must be taken in its performance. This report provides an update of the efforts to advance the understanding of this method and to increase its application to the nondestructive evaluation of composite materials. Included are descriptions of a novel optical system that is capable of measuring in-plane and out-of-plane displacements, an IBM PC-based data acquisition system, an extensive data analysis software package, the azimuthal variation of acousto-ultrasonic behavior in graphite/epoxy laminates, and preliminary examination of processing variation in graphite-aluminum tubes.

Diagnosis of lesions of the acetabular labrum, of the labral-chondral transition zone, and of the cartilage in femoroacetabular impingement: Correlation between direct magnetic resonance arthrography and hip arthroscopy.

PubMed

Crespo Rodríguez, A M; de Lucas Villarrubia, J C; Pastrana Ledesma, M A; Millán Santos, I; Padrón, M

2015-01-01

To determine the sensitivity and accuracy of direct MR arthrography in the diagnosis of intra-articular lesions associated with femoroacetabular impingement. We used direct MR arthrography to study 51 patients with femoroacetabular impingement who underwent arthroscopic hip surgery. Surgery demonstrated 37 labral tears, 44 lesions in the labral-chondral transitional zone, and 40 lesions of the articular cartilage. We correlated the findings at preoperative direct MR arthrography with those of hip arthroscopy and calculated the sensitivity, specificity, positive predictive value, negative predictive value, and validity index for direct MR arthrography. The sensitivity and specificity of MR arthrography were 94.5% and 100%, respectively, for diagnosing labral tears, 100% and 87.5%, respectively, for diagnosing lesions of the labral-chondral transition zone, and 92.5% and 54.5%, respectively, for diagnosing lesions of the articular cartilage. The negative predictive value of MR arthrography for lesions of the labral-chondral transitional zone was 100%. MR arthrography accurately defined extensive lesions of the cartilage and the secondary osseous changes (the main factor in poor prognosis), although its diagnostic performance was not so good in small chondral lesions. In patients with femoroacetabular impingement, direct MR arthrography can adequately detect and characterize lesions of the acetabular labrum and of the labral-chondral transitional zone as well as extensive lesions of the articular cartilage and secondary osseous changes. Copyright © 2013 SERAM. Published by Elsevier España, S.L.U. All rights reserved.

Development of a Pattern Recognition Methodology for Determining Operationally Optimal Heat Balance Instrumentation Calibration Schedules

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

Kurt Beran; John Christenson; Dragos Nica

2002-12-15

The goal of the project is to enable plant operators to detect with high sensitivity and reliability the onset of decalibration drifts in all of the instrumentation used as input to the reactor heat balance calculations. To achieve this objective, the collaborators developed and implemented at DBNPS an extension of the Multivariate State Estimation Technique (MSET) pattern recognition methodology pioneered by ANAL. The extension was implemented during the second phase of the project and fully achieved the project goal.

Bacillus anthracis lethal toxin induces TNF-α–independent hypoxia-mediated toxicity in mice

PubMed Central

Moayeri, Mahtab; Haines, Diana; Young, Howard A.; Leppla, Stephen H.

2003-01-01

Bacillus anthracis lethal toxin (LT) is the major virulence factor of anthrax and reproduces most of the laboratory manifestations of the disease in animals. We studied LT toxicity in BALB/cJ and C57BL/6J mice. BALB/cJ mice became terminally ill earlier and with higher frequency than C57BL/6J mice. Timed histopathological analysis identified bone marrow, spleen, and liver as major affected organs in both mouse strains. LT induced extensive hypoxia. Crisis was due to extensive liver necrosis accompanied by pleural edema. There was no evidence of disseminated intravascular coagulation or renal dysfunction. Instead, analyses revealed hepatic dysfunction, hypoalbuminemia, and vascular/oxygenation insufficiency. Of 50 cytokines analyzed, BALB/cJ mice showed rapid but transitory increases in specific factors including KC, MCP-1/JE, IL-6, MIP-2, G-CSF, GM-CSF, eotaxin, FasL, and IL-1β. No changes in TNF-α occurred. The C57BL/6J mice did not mount a similar cytokine response. These factors were not induced in vitro by LT treatment of toxin-sensitive macrophages. The evidence presented shows that LT kills mice through a TNF-α–independent, FasL-independent, noninflammatory mechanism that involves hypoxic tissue injury but does not require macrophage sensitivity to toxin. PMID:12952916

Sensitizing and Eliciting Capacity of Egg White Proteins in BALB/c Mice As Affected by Processing.

PubMed

Pablos-Tanarro, Alba; Lozano-Ojalvo, Daniel; Martínez-Blanco, Mónica; López-Fandiño, Rosina; Molina, Elena

2017-06-07

This study assesses to what extent technological processes that lead to different degrees of denaturation of egg white proteins affect their allergenicity. We focused on heat (80 °C, 10 min) and high-pressure (400 MPa and 37 °C, 10 min) treatments and used a BALB/c mouse model of food allergy. Oral sensitization to egg white using cholera toxin as adjuvant induced the production of IgE and IgG1 isotypes and led to severe clinical signs following challenge with the allergen. Extensive protein denaturation caused by heat treatment increased its ability to induce Th1 responses and reduced both its sensitizing and eliciting capacity. Heated egg white stimulated the production of IgE over IgG1 antibodies directed, at least in part, toward new epitopes exposed as a result of heat treatment. Conversely, partial denaturation caused by high-pressure treatment increased the ability of egg white to stimulate Th2 responses and its allergenic potential.

Physical Employment Standards for UK Firefighters

PubMed Central

Stevenson, Richard D.M.; Siddall, Andrew G.; Turner, Philip F.J.; Bilzon, James L.J.

2017-01-01

Objective: The aim of this study was to assess sensitivity and specificity of surrogate physical ability tests as predictors of criterion firefighting task performance and to identify corresponding minimum muscular strength and endurance standards. Methods: Fifty-one (26 male; 25 female) participants completed three criterion tasks (ladder lift, ladder lower, ladder extension) and three corresponding surrogate tests [one-repetition maximum (1RM) seated shoulder press; 1RM seated rope pull-down; repeated 28 kg seated rope pull-down]. Surrogate test standards were calculated that best identified individuals who passed (sensitivity; true positives) and failed (specificity; true negatives) criterion tasks. Results: Best sensitivity/specificity achieved were 1.00/1.00 for a 35 kg seated shoulder press, 0.79/0.92 for a 60 kg rope pull-down, and 0.83/0.93 for 23 repetitions of the 28 kg rope pull-down. Conclusions: These standards represent performance on surrogate tests commensurate with minimum acceptable performance of essential strength-based occupational tasks in UK firefighters. PMID:28045801

Two endogenous proteins that induce cell wall extension in plants

NASA Technical Reports Server (NTRS)

McQueen-Mason, S.; Durachko, D. M.; Cosgrove, D. J.

1992-01-01

Plant cell enlargement is regulated by wall relaxation and yielding, which is thought to be catalyzed by elusive "wall-loosening" enzymes. By employing a reconstitution approach, we found that a crude protein extract from the cell walls of growing cucumber seedlings possessed the ability to induce the extension of isolated cell walls. This activity was restricted to the growing region of the stem and could induce the extension of isolated cell walls from various dicot stems and the leaves of amaryllidaceous monocots, but was less effective on grass coleoptile walls. Endogenous and reconstituted wall extension activities showed similar sensitivities to pH, metal ions, thiol reducing agents, proteases, and boiling in methanol or water. Sequential HPLC fractionation of the active wall extract revealed two proteins with molecular masses of 29 and 30 kD associated with the activity. Each protein, by itself, could induce wall extension without detectable hydrolytic breakdown of the wall. These proteins appear to mediate "acid growth" responses of isolated walls and may catalyze plant cell wall extension by a novel biochemical mechanism.

Control of growth of juvenile leaves of Eucalyptus globulus: effects of leaf age.

PubMed

Metcalfe, J C; Davies, W J; Pereira, J S

1991-12-01

Biophysical variables influencing the expansion of plant cells (yield threshold, cell wall extensibility and turgor) were measured in individual Eucalyptus globulus leaves from the time of emergence until cessation of growth. Leaf water relations variables and growth rates were determined as relative humidity was changed on an hourly basis. Yield threshold and cell wall extensibility were estimated from plots of leaf growth rate versus turgor. Cell wall extensibility was also measured by the Instron technique, and yield threshold was determined experimentally both by stress relaxation in a psychrometer chamber and by incubation in a range of polyethylene glycol solutions. Once emerging leaves reached approximately 5 cm(2) in size, increases in leaf area were rapid throughout the expansive phase and varied little between light and dark periods. Both leaf growth rate and turgor were sensitive to changes in humidity, and in the longer term, both yield threshold and cell wall extensibility changed as the leaf aged. Rapidly expanding leaves had a very low yield threshold and high cell wall extensibility, whereas mature leaves had low cell wall extensibility. Yield threshold increased with leaf age.

Contrasting influences of Drosophila white/mini-white on ethanol sensitivity in two different behavioral assays.

PubMed

Chan, Robin F; Lewellyn, Lara; DeLoyht, Jacqueline M; Sennett, Kristyn; Coffman, Scarlett; Hewitt, Matthew; Bettinger, Jill C; Warrick, John M; Grotewiel, Mike

2014-06-01

The fruit fly Drosophila melanogaster has been used extensively to investigate genetic mechanisms of ethanol (EtOH)-related behaviors. Many past studies in flies, including studies from our laboratory, have manipulated gene expression using transposons carrying the genetic-phenotypic marker mini-white(mini-w), a derivative of the endogenous gene white(w). Whether the mini-w transgenic marker or the endogenous w gene influences behavioral responses to acute EtOH exposure in flies has not been systematically investigated. We manipulated mini-w and w expression via (i) transposons marked with mini-w, (ii) RNAi against mini-w and w, and (iii) a null allele of w. We assessed EtOH sensitivity and tolerance using a previously described eRING assay (based on climbing in the presence of EtOH) and an assay based on EtOH-induced sedation. In eRING assays, EtOH-induced impairment of climbing correlated inversely with expression of the mini-w marker from a series of transposon insertions. Additionally, flies harboring a null allele of w or flies with RNAi-mediated knockdown of mini-w were significantly more sensitive to EtOH in eRING assays than controls expressing endogenous w or the mini-w marker. In contrast, EtOH sensitivity and rapid tolerance measured in the EtOH sedation assay were not affected by decreased expression of mini-w or endogenous w in flies. EtOH sensitivity measured in the eRING assay is noticeably influenced by w and mini-w, making eRING problematic for studies on EtOH-related behavior in Drosophila using transgenes marked with mini-w. In contrast, the EtOH sensitivity assay described here is a suitable behavioral paradigm for studies on EtOH sensitivity and rapid tolerance in Drosophila including those that use widely available transgenes marked with mini-w. Copyright © 2014 by the Research Society on Alcoholism.

Increased pain sensitivity but normal function of exercise induced analgesia in hip and knee osteoarthritis--treatment effects of neuromuscular exercise and total joint replacement.

PubMed

Kosek, E; Roos, E M; Ageberg, E; Nilsdotter, A

2013-09-01

To assess exercise induced analgesia (EIA) and pain sensitivity in hip and knee osteoarthritis (OA) and to study the effects of neuromuscular exercise and surgery on these parameters. The dataset consisted of knee (n = 66) and hip (n = 47) OA patients assigned for total joint replacement at Lund University Hospital undergoing pre-operative neuromuscular exercise and 43 matched controls. Sensitivity to pressure pain was assessed by pressure algometry at 10 sites. Subjects were then instructed to perform a standardized static knee extension. Pressure pain thresholds (PPTs) were assessed at the contracting quadriceps muscle (Q) and at the resting deltoid muscle (D) before and during contraction. The relative increase in PPTs during contraction was taken as a measure of localized (Q) or generalized (D) EIA. Patients were assessed at baseline, following on average 12 weeks of neuromuscular exercise and 3 months following surgery. We found a normal function of EIA in OA patients at baseline. Previous studies have reported beneficial effects of physical exercise on pain modulation in healthy subjects. However, no treatment effects on EIA were seen in OA patients despite the increase in muscle strength following neuromuscular exercise and reduced pain following surgery. Compared to controls, OA patients had increased pain sensitivity and no beneficial effects on pain sensitivity were seen following treatment. To our knowledge, this is the first study of EIA in OA patients. Despite increased pain sensitivity, OA patients had a normal function of EIA. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Allergy and orthodontics

PubMed Central

Chakravarthi, Sunitha; Padmanabhan, Sridevi; Chitharanjan, Arun B.

2012-01-01

The aim of this paper is to review the current literature on allergy in orthodontics and to identify the predisposing factors and the implications of the allergic reaction in the management of patients during orthodontic treatment. A computerized literature search was conducted in PubMed for articles published on allergy in relation to orthodontics. The MeSH term used was allergy and orthodontics. Allergic response to alloys in orthodontics, particularly nickel, has been extensively studied and several case reports of nickel-induced contact dermatitis have been documented. Current evidence suggests that the most common allergic reaction reported in orthodontics is related to nickel in orthodontic appliances and allergic response is more common in women due to a previous sensitizing exposure from nickel in jewellery. Studies have implicated allergy in the etiology of hypo-dontia. It has also been considered as a high-risk factor for development of extensive root resorption during the course of orthodontic treatment. This review discusses the relationship and implications of allergy in orthodontics. PMID:24987632

Functionalized copper(II)-phthalocyanine in solution and as thin film: photochemical and morphological characterization toward applications.

PubMed

Ingrosso, Chiara; Curri, M Lucia; Fini, Paola; Giancane, Gabriele; Agostiano, Angela; Valli, Ludovico

2009-09-01

This article reports on an extensive investigation on a functionalized phthalocyanine, namely, copper(II) tetrakis-(isopropoxy-carbonyl)-phthalocyanine (TIPCuPc). The self-association of the molecules is extensively described in solution in different solvents (DMSO, DMF, CHCl(3), pyridine) by means of UV-vis steady state spectroscopy at the air/water interface by Brewster angle microscopy (BAM) and in thin films by using atomic force microscopy (AFM). We investigated the morphology of TIPCuPc as thin film by evaluating different factors: temperature, solvent, concentration, transferring procedure (spin-coating and Langmuir-Schafer technique), and nature of the substrate (mica and quartz). The behavior of the molecules under UV light irradiation and their thermal stability were studied as well. Such a detailed study can allow a suitable processing of this phthalocyanine derivative for future applications. Here the photoelectrochemical activity of the phthalocyanine was investigated when suitably combined as sensitizer with rodlike TiO(2) nanocrystals (NCs) in hybrid junctions integrated in a photoelectrochemical cell.

SCALE 6.2 Continuous-Energy TSUNAMI-3D Capabilities

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

Perfetti, Christopher M; Rearden, Bradley T

2015-01-01

The TSUNAMI (Tools for Sensitivity and UNcertainty Analysis Methodology Implementation) capabilities within the SCALE code system make use of sensitivity coefficients for an extensive number of criticality safety applications, such as quantifying the data-induced uncertainty in the eigenvalue of critical systems, assessing the neutronic similarity between different systems, quantifying computational biases, and guiding nuclear data adjustment studies. The need to model geometrically complex systems with improved ease of use and fidelity and the desire to extend TSUNAMI analysis to advanced applications have motivated the development of a SCALE 6.2 module for calculating sensitivity coefficients using three-dimensional (3D) continuous-energy (CE) Montemore » Carlo methods: CE TSUNAMI-3D. This paper provides an overview of the theory, implementation, and capabilities of the CE TSUNAMI-3D sensitivity analysis methods. CE TSUNAMI contains two methods for calculating sensitivity coefficients in eigenvalue sensitivity applications: (1) the Iterated Fission Probability (IFP) method and (2) the Contributon-Linked eigenvalue sensitivity/Uncertainty estimation via Track length importance CHaracterization (CLUTCH) method. This work also presents the GEneralized Adjoint Response in Monte Carlo method (GEAR-MC), a first-of-its-kind approach for calculating adjoint-weighted, generalized response sensitivity coefficients—such as flux responses or reaction rate ratios—in CE Monte Carlo applications. The accuracy and efficiency of the CE TSUNAMI-3D eigenvalue sensitivity methods are assessed from a user perspective in a companion publication, and the accuracy and features of the CE TSUNAMI-3D GEAR-MC methods are detailed in this paper.« less

Dehydration Preparation of Mouse Sperm for Vitrification and Rapid Laser Warming.

PubMed

Paredes, E; Mazur, P

Mice are fundamental models of study due to their ease of breeding, manipulation, and the well-studied genome. There has been extensive research focused on the cryopreservation of mouse germaplasm, as a way to help maintain the different transgenic mouse breeds. The first protocols for mouse sperm were developed in the 90's using slow cooling and a mixture of raffinose and glycerol. Since then, the rate of success reported remains highly variable. The Aim of this work is to study factors that are key for developing vitrification protocols for ultra-rapid laser warming of mouse sperm. Our results show that due to the exquisite sensitivity of sperm cells to osmotic excursions, our target levels of dehydration (~85% water content) cannot be achieved without causing a significant decrease in sperm motility and membrane fusion. It seems likely that mouse sperm vitrification is going to be difficult to develop due to the exquisite sensitivity of mouse sperm cells to handling and dehydration.

The effect of building facade reflectivity on urban dwellers in tropics.

NASA Astrophysics Data System (ADS)

Ishak, N. M.; Hien, W. N.; Jenatabadi, H. S.; Ignatius, M.; Yaman, R.

2018-02-01

With the rapid growth and use of modern architecture practices for high-rise buildings, highly reflective materials have been adopted extensively for aesthetical reasons. However, outdoor glare from highly reflective facades might cause thermal and visual problems towards the occupants of neighbouring buildings and outdoor dwellers, particularly pedestrians. In tropical countries, this negative impact can be greater due to the higher solar radiation received throughout the year. At the present, there are few building guidelines limiting outdoor glare, or daylight reflectance from a building facade. This study aims to introduce a framework for outdoor glare studies that focus on perceived glare from highly reflective facades by pedestrians in Singapore. The introduced framework includes age, glare time, glare duration, avoidance and sensitiveness. For this study, the survey is carried out with the application of Structural Equation Modelling (SEM). This paper is helpful for planners, designers, and engineers to estimate the sensitivity of pedestrians’ discomfort glare and towards the creation of sustainable architecture in Singapore.

In situ study of the antibacterial activity and mechanism of action of silver nanoparticles by surface-enhanced Raman spectroscopy.

PubMed

Cui, Li; Chen, Pengyu; Chen, Shaode; Yuan, Zhihua; Yu, Changping; Ren, Bin; Zhang, Kaisong

2013-06-04

Silver nanoparticles (Ag NPs) are extensively used as an antibacterial additive in commercial products and their release has caused environmental risk. However, conventional methods for the toxicity detection of Ag NPs are very time consuming and the mechanisms of action are not clear. We developed a new, in situ, rapid, and sensitive fingerprinting approach, using surface-enhanced Raman spectroscopy (SERS), to study the antibacterial activity and mechanism of Ag NPs of 80 and 18 nm (Ag80 and Ag18, respectively), by using the strong electromagnetic enhancement generated by Ag NPs. Sensitive spectra changes representing various biomolecules in bacteria were observed with increasing concentrations of Ag NPs. They not only allowed SERS to monitor the antibacterial activity of Ag NPs of different sizes in different water media but also to study the antibacterial mechanism at the molecular level. Ag18 were found to be more toxic than Ag80 in water, but their toxicity declined to a similar level in the PBS medium. The antibacterial mechanism was proposed on the basis of a careful identification of the chemical origins by comparing the SERS spectra with model compounds. The dramatic change in protein, hypoxanthine, adenosine, and guanosine bands suggested that Ag NPs have a significant impact on the protein and metabolic processes of purine. Finally, by adding nontoxic and SERS active Au NPs, SERS was successfully utilized to study the action mode of the NPs unable to produce an observable SERS signal. This work opens a window for the future extensive SERS studies of the antibacterial mechanism of a great variety of non-SERS-active NPs.

Optimizing screening for tuberculosis and hepatitis B prior to starting tumor necrosis factor-α inhibitors in Crohn's disease.

PubMed

van der Have, Mike; Oldenburg, Bas; Fidder, Herma H; Belderbos, Tim D G; Siersema, Peter D; van Oijen, Martijn G H

2014-03-01

Treatment with tumor necrosis factor-α (TNF-α) inhibitors in patients with Crohn's disease (CD) is associated with potentially serious infections, including tuberculosis (TB) and hepatitis B virus (HBV). We assessed the cost-effectiveness of extensive TB screening and HBV screening prior to initiating TNF-α inhibitors in CD. We constructed two Markov models: (1) comparing tuberculin skin test (TST) combined with chest X-ray (conventional TB screening) versus TST and chest X-ray followed by the interferon-gamma release assay (extensive TB screening) in diagnosing TB; and (2) HBV screening versus no HBV screening. Our base-case included an adult CD patient starting with infliximab treatment. Input parameters were extracted from the literature. Direct medical costs were assessed and discounted following a third-party payer perspective. The main outcome was the incremental cost-effectiveness ratio (ICER). Sensitivity and Monte Carlo analyses were performed over wide ranges of probability and cost estimates. At base-case, the ICERs of extensive screening and HBV screening were €64,340 and €75,760 respectively to gain one quality-adjusted life year. Sensitivity analyses concluded that extensive TB screening was a cost-effective strategy if the latent TB prevalence is more than 12 % or if the false positivity rate of TST is more than 20 %. HBV screening became cost-effective if HBV reactivation or HBV-related mortality is higher than 37 and 62 %, respectively. Extensive TB screening and HBV screening are not cost-effective compared with conventional TB screening and no HBV screening, respectively. However, when targeted at high-risk patient groups, these screening strategies are likely to become cost-effective.

A model for growth of a single fungal hypha based on well-mixed tanks in series: simulation of nutrient and vesicle transport in aerial reproductive hyphae.

PubMed

Balmant, Wellington; Sugai-Guérios, Maura Harumi; Coradin, Juliana Hey; Krieger, Nadia; Furigo Junior, Agenor; Mitchell, David Alexander

2015-01-01

Current models that describe the extension of fungal hyphae and development of a mycelium either do not describe the role of vesicles in hyphal extension or do not correctly describe the experimentally observed profile for distribution of vesicles along the hypha. The present work uses the n-tanks-in-series approach to develop a model for hyphal extension that describes the intracellular transport of nutrient to a sub-apical zone where vesicles are formed and then transported to the tip, where tip extension occurs. The model was calibrated using experimental data from the literature for the extension of reproductive aerial hyphae of three different fungi, and was able to describe different profiles involving acceleration and deceleration of the extension rate. A sensitivity analysis showed that the supply of nutrient to the sub-apical vesicle-producing zone is a key factor influencing the rate of extension of the hypha. Although this model was used to describe the extension of a single reproductive aerial hypha, the use of the n-tanks-in-series approach to representing the hypha means that the model has the flexibility to be extended to describe the growth of other types of hyphae and the branching of hyphae to form a complete mycelium.

Household decision-making around food in rural Tajikistan: a cross-sectional study to help extension workers in the field

PubMed Central

Wood, Elizabeth A.; McNamara, Katharine; Kowalewska, Agata; Ludgate, Nargiza

2018-01-01

This study was conducted to research and develop recommendations for gender transformative approaches that will address misconceptions around food and nutrition, and reducing barriers around dietary diversity within rural Khatlon Province, Tajikistan. Most of the population in Tajikistan live in rural areas and spend a large part of their income on food. While stunting in children under 5 years has decreased, acute malnutrition and the number of underweight children has increased. This is a qualitative, cross-sectional study that involved secondary data analysis, key informant interviews (KIIs), and focus group discussions (FGDs) to gauge appropriate interventions for agricultural extension agents seeking to improve the nutritional outcomes of their communities. In February of 2017, data were collected from 4 KIIs and 15 FGDs that were stratified as mothers with young children, mothers-in-law, and husbands, across 12 different villages. Analysis of the KIIs and FGDs included NVivo software for coding and to uncover the most salient themes and characteristics from each. The participants of this study reported several misconceptions and taboos surrounding certain foods, especially during pregnancy, and food practices for children under the age of 5 years. Results also indicated a household hierarchy of decision-making surrounding food that included who buys, cooks, and decides what to buy. The findings of this study will be used as a springboard to launch gender-responsive and nutrition-sensitive interventions through the local agricultural extension agents. PMID:29599685

Avian sensitivity to mortality: prioritising migratory bird species for assessment at proposed wind farms.

PubMed

Desholm, Mark

2009-06-01

Wind power generation is likely to constitute one of the most extensive human physical exploitation activities of European marine areas in the near future. The many millions of migrating birds that pass these man-made obstacles are protected by international obligations and the subject of public concerns. Yet some bird species are more sensitive to bird-wind turbine mortality than others. This study developed a simple and logical framework for ranking bird species with regard to their relative sensitivity to bird-wind turbine-collisions, and applied it to a data set comprising 38 avian migrant species at the Nysted offshore wind farm in Denmark. Two indicators were selected to characterize the sensitivity of each individual species: 1) relative abundance and 2) demographic sensitivity (elasticity of population growth rate to changes in adult survival). In the case-study from the Nysted offshore wind farm, birds of prey and waterbirds dominated the group of high priority species and only passerines showed a low risk of being impacted by the wind farm. Even where passerines might be present in very high numbers, they often represent insignificant segments of huge reference populations that, from a demographic point of view, are relatively insensitive to wind farm-related adult mortality. It will always be important to focus attention and direct the resources towards the most sensitive species to ensure cost-effective environmental assessments in the future, and in general, this novel index seems capable of identifying the species that are at high risk of being adversely affected by wind farms.

Differential cellular responses in healthy mice and in mice with established airway inflammation when exposed to hematite nanoparticles.

PubMed

Gustafsson, Åsa; Bergström, Ulrika; Ågren, Lina; Österlund, Lars; Sandström, Thomas; Bucht, Anders

2015-10-01

The aim of this study was to investigate the inflammatory and immunological responses in airways and lung-draining lymph nodes (LDLNs), following lung exposure to iron oxide (hematite) nanoparticles (NPs). The responses to the hematite NPs were evaluated in both healthy non-sensitized mice, and in sensitized mice with an established allergic airway disease. The mice were exposed intratracheally to either hematite NPs or to vehicle (PBS) and the cellular responses were evaluated on days 1, 2, and 7, post-exposure. Exposure to hematite NPs increased the numbers of neutrophils, eosinophils, and lymphocytes in the airways of non-sensitized mice on days 1 and 2 post-exposure; at these time points the number of lymphocytes was also elevated in the LDLNs. In contrast, exposing sensitized mice to hematite NPs induced a rapid and unspecific cellular reduction in the alveolar space on day 1 post-exposure; a similar decrease of lymphocytes was also observed in the LDLN. The results indicate that cells in the airways and in the LDLN of individuals with established airway inflammation undergo cell death when exposed to hematite NPs. A possible explanation for this toxic response is the extensive generation of reactive oxygen species (ROS) in the pro-oxidative environment of inflamed airways. This study demonstrates how sensitized and non-sensitized mice respond differently to hematite NP exposure, and it highlights the importance of including individuals with respiratory disorders when evaluating health effects of inhaled nanomaterials. Copyright © 2015 Elsevier Inc. All rights reserved.

Evidence that two alkyl ester quaternary ammonium compounds lack substantial human skin-sensitizing potential.

PubMed

Jowsey, Ian R; Kligman, Albert M; White, Ian R; Goossens, An; Basketter, David A

2007-03-01

Alkyl ester quaternary ammonium compounds (ester quats) are used extensively in fabric rinse conditioners. It is important to document in the literature the outcome of historical studies that were performed to assess the risk of adverse skin effects associated with their use. (1) To document the outcomes of historical studies performed to evaluate the skin sensitizing potential of two ester quats (the di-[hardened tallow fatty acid] ester of 2,3-dihydroxypropyl-trimethyl ammonium chloride [HEQ] and the dialkyl ester of triethanol ammonium methyl sulfate [TEA-Quat]) and (2) to demonstrate that these ester quats lack marked skin-sensitizing potential in humans, such that they do not present a risk of contact allergy for consumers who use fabric rinse conditioners. Each material was assessed in the human maximization test in a panel of 25 volunteers. Diagnostic patch testing was also performed with each material in a population of 239 patients undergoing routine patch testing for suspected allergic contact dermatitis. These data are also considered in the context of an exposure-based quantitative risk assessment. Neither HEQ nor TEA-Quat was found to cause skin sensitization under the conditions of the human maximization test. No evidence of contact allergy to the materials was found among the relatively small population assessed by diagnostic patch testing. This study provides evidence that HEQ and TEA-Quat lack substantial skin-sensitizing potential in humans. Taken together with similar data for other ester quats, it suggests that compounds in this class are unlikely to be significant human contact allergens.

Large-Scale Features of Pliocene Climate: Results from the Pliocene Model Intercomparison Project

NASA Technical Reports Server (NTRS)

Haywood, A. M.; Hill, D.J.; Dolan, A. M.; Otto-Bliesner, B. L.; Bragg, F.; Chan, W.-L.; Chandler, M. A.; Contoux, C.; Dowsett, H. J.; Jost, A.;

How Reducing was the Late Devonian Ocean? The Role of Extensive Expansion of Anoxia in Marine Biogeochemical Cycles of Redox Sensitive Metals.

NASA Astrophysics Data System (ADS)

Sahoo, S. K.; Jin, H.

2017-12-01

The evolution of Earth's biogeochemical cycles is intimately linked to the oxygenation of the oceans and atmosphere. The Late Devonian is no exception as its characterized with mass extinction and severe euxinia. Here we use concentrations of Molybdenum (Mo), Vanadium (V), Uranium (U) and Chromium (Cr) in organic rich black shales from the Lower Bakken Formation of the Williston Basin, to explore the relationship between extensive anoxia vs. euxinia and it's relation with massive release of oxygen in the ocean atmosphere system. XRF data from 4 core across the basin shows that modern ocean style Mo, U and Cr enrichments are observed throughout the Lower Bakken Formation, yet V is not enriched until later part of the formation. Given the coupling between redox-sensitive-trace element cycles and ocean redox, various models for Late Devonian ocean chemistry imply different effects on the biogeochemical cycling of major and trace nutrients. Here, we examine the differing redox behavior of molybdenum and vanadium under an extreme anoxia and relatively low extent of euxinia. The model suggests that Late Devonian was perhaps extensively anoxic- 40-50% compared to modern seafloor area, and a very little euxinia. Mo enrichments extend up to 500 p.p.m. throughout the section, representative of a modern reducing ocean. However, coeval low V enrichments only support towards anoxia, where anoxia is a source of V, and a sink for Mo. Our model suggests that the oceanic V reservoir is extremely sensitive to perturbations in the extent of anoxic condition, particularly during post glacial times.

Sensitivity Observing System Experiment (SOSE)-a new effective NWP-based tool in designing the global observing system

NASA Astrophysics Data System (ADS)

Marseille, Gert-Jan; Stoffelen, Ad; Barkmeijer, Jan

2008-03-01

Lacking an established methodology to test the potential impact of prospective extensions to the global observing system (GOS) in real atmospheric cases we developed such a method, called Sensitivity Observing System Experiment (SOSE). For example, since the GOS is non uniform it is of interest to investigate the benefit of complementary observing systems filling its gaps. In a SOSE adjoint sensitivity structures are used to define a pseudo true atmospheric state for the simulation of the prospective observing system. Next, the synthetic observations are used together with real observations from the existing GOS in a state-of-the-art Numerical Weather Prediction (NWP) model to assess the potential added value of the new observing system. Unlike full observing system simulation experiments (OSSE), SOSE can be applied to real extreme events that were badly forecast operationally and only requires the simulation of the new instrument. As such SOSE is an effective tool, for example, to define observation requirements for extensions to the GOS. These observation requirements may serve as input for the design of an operational network of prospective observing systems. In a companion paper we use SOSE to simulate potential future space borne Doppler Wind Lidar (DWL) scenarios and assess their capability to sample meteorologically sensitive areas not well captured by the current GOS, in particular over the Northern Hemisphere oceans.

Sensitive periods in affective development: nonlinear maturation of fear learning.

PubMed

Hartley, Catherine A; Lee, Francis S

2015-01-01

At specific maturational stages, neural circuits enter sensitive periods of heightened plasticity, during which the development of both brain and behavior are highly receptive to particular experiential information. A relatively advanced understanding of the regulatory mechanisms governing the initiation, closure, and reinstatement of sensitive period plasticity has emerged from extensive research examining the development of the visual system. In this article, we discuss a large body of work characterizing the pronounced nonlinear changes in fear learning and extinction that occur from childhood through adulthood, and their underlying neural substrates. We draw upon the model of sensitive period regulation within the visual system, and present burgeoning evidence suggesting that parallel mechanisms may regulate the qualitative changes in fear learning across development.

Sensitive Periods in Affective Development: Nonlinear Maturation of Fear Learning

PubMed Central

Hartley, Catherine A; Lee, Francis S

2015-01-01

At specific maturational stages, neural circuits enter sensitive periods of heightened plasticity, during which the development of both brain and behavior are highly receptive to particular experiential information. A relatively advanced understanding of the regulatory mechanisms governing the initiation, closure, and reinstatement of sensitive period plasticity has emerged from extensive research examining the development of the visual system. In this article, we discuss a large body of work characterizing the pronounced nonlinear changes in fear learning and extinction that occur from childhood through adulthood, and their underlying neural substrates. We draw upon the model of sensitive period regulation within the visual system, and present burgeoning evidence suggesting that parallel mechanisms may regulate the qualitative changes in fear learning across development. PMID:25035083

US 93 preconstruction wildlife monitoring field methods handbook : final report.

DOT National Transportation Integrated Search

2006-11-01

The US 93 reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to occur in the continental United States. The reconstruction will include install...

77 FR 39459 - Fisheries of the United States; National Standard 1 Guidelines; Extension of Public Comment Period

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-03

... business information or otherwise sensitive or protected information. NMFS will accept anonymous comments (enter ``N/A'' in the required fields if you wish to remain anonymous). Attachments to electronic...

Mixture models in diagnostic meta-analyses--clustering summary receiver operating characteristic curves accounted for heterogeneity and correlation.

PubMed

Schlattmann, Peter; Verba, Maryna; Dewey, Marc; Walther, Mario

2015-01-01

Bivariate linear and generalized linear random effects are frequently used to perform a diagnostic meta-analysis. The objective of this article was to apply a finite mixture model of bivariate normal distributions that can be used for the construction of componentwise summary receiver operating characteristic (sROC) curves. Bivariate linear random effects and a bivariate finite mixture model are used. The latter model is developed as an extension of a univariate finite mixture model. Two examples, computed tomography (CT) angiography for ruling out coronary artery disease and procalcitonin as a diagnostic marker for sepsis, are used to estimate mean sensitivity and mean specificity and to construct sROC curves. The suggested approach of a bivariate finite mixture model identifies two latent classes of diagnostic accuracy for the CT angiography example. Both classes show high sensitivity but mainly two different levels of specificity. For the procalcitonin example, this approach identifies three latent classes of diagnostic accuracy. Here, sensitivities and specificities are quite different as such that sensitivity increases with decreasing specificity. Additionally, the model is used to construct componentwise sROC curves and to classify individual studies. The proposed method offers an alternative approach to model between-study heterogeneity in a diagnostic meta-analysis. Furthermore, it is possible to construct sROC curves even if a positive correlation between sensitivity and specificity is present. Copyright © 2015 Elsevier Inc. All rights reserved.

Sensitivity of aquatic ecosystems to climatic and anthropogenic changes: The basin and range, American Southwest and Mexico

USGS Publications Warehouse

Grimm, N. B.; Chacon, A.; Dahm, Clifford N.; Hostetler, S.W.; Lind, O.T.; Starkweather, P.L.; Wurtsbaugh, W.W.

1997-01-01

Variability and unpredictability are characteristics of the aquatic ecosystems, hydrological patterns and climate of the largely dryland region that encompasses the Basin and Range, American Southwest and western Mexico. Neither hydrological nor climatological models for the region are sufficiently developed to describe the magnitude or direction of change in response to increased carbon dioxide; thus, an attempt to predict specific responses of aquatic ecosystems is premature. Instead, we focus on the sensitivity of rivers, streams, springs, wetlands, reservoirs, and lakes of the region to potential changes in climate, especially those inducing a change in hydrological patterns such as amount, timing and predictability of stream flow. The major sensitivities of aquatic ecosystems are their permanence and even existence in the face of potential reduced net basin supply of water, stability of geomorphological structure and riparian ecotones with alterations in disturbance regimes, and water quality changes resulting from a modified water balance. In all of these respects, aquatic ecosystems of the region are also sensitive to the extensive modifications imposed by human use of water resources, which underscores the difficulty of separating this type of anthropogenic change from climate change. We advocate a focus in future research on reconstruction and analysis of past climates and associated ecosystem characteristics, long-term studies to discriminate directional change vs. year to year variability (including evidence of aquatic ecosystem responses or sensitivity to extremes), and studies of ecosystems affected by human activity. ?? 1997 by John Wiley & Sons, Ltd.

What Constitutes a "Good" Sensitivity Analysis? Elements and Tools for a Robust Sensitivity Analysis with Reduced Computational Cost

NASA Astrophysics Data System (ADS)

Razavi, Saman; Gupta, Hoshin; Haghnegahdar, Amin

2016-04-01

Global sensitivity analysis (GSA) is a systems theoretic approach to characterizing the overall (average) sensitivity of one or more model responses across the factor space, by attributing the variability of those responses to different controlling (but uncertain) factors (e.g., model parameters, forcings, and boundary and initial conditions). GSA can be very helpful to improve the credibility and utility of Earth and Environmental System Models (EESMs), as these models are continually growing in complexity and dimensionality with continuous advances in understanding and computing power. However, conventional approaches to GSA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we identify several important sensitivity-related characteristics of response surfaces that must be considered when investigating and interpreting the ''global sensitivity'' of a model response (e.g., a metric of model performance) to its parameters/factors. Accordingly, we present a new and general sensitivity and uncertainty analysis framework, Variogram Analysis of Response Surfaces (VARS), based on an analogy to 'variogram analysis', that characterizes a comprehensive spectrum of information on sensitivity. We prove, theoretically, that Morris (derivative-based) and Sobol (variance-based) methods and their extensions are special cases of VARS, and that their SA indices are contained within the VARS framework. We also present a practical strategy for the application of VARS to real-world problems, called STAR-VARS, including a new sampling strategy, called "star-based sampling". Our results across several case studies show the STAR-VARS approach to provide reliable and stable assessments of "global" sensitivity, while being at least 1-2 orders of magnitude more efficient than the benchmark Morris and Sobol approaches.

Photonic Potential of Haloarchaeal Pigment Bacteriorhodopsin for Future Electronics: A Review.

PubMed

Ashwini, Ravi; Vijayanand, S; Hemapriya, J

2017-08-01

Haloarchaea are known for its adaptation in extreme saline environment. Halophilic archaea produces carotenoid pigments and proton pumps to protect them from extremes of salinity. Bacteriorhodopsin (bR) is a light-driven proton pump that resides in the membrane of haloarchaea Halobacterium salinarum. The photocycle of Bacteriorhodopsin passes through several states from K to O, finally liberating ATP for host's survival. Extensive studies on Bacteriorhodopsin photocycle has provided in depth knowledge on their sequential mechanism of converting solar energy into chemical energy inside the cell. This ability of Bacteriorhodopsin to harvest sunlight has now been experimented to exploit the unexplored and extensively available solar energy in various biotechnological applications. Currently, bacteriorhodopsin finds its importance in dye-sensitized solar cell (DSSC), logic gates (integrated circuits, IC's), optical switching, optical memories, storage devices (random access memory, RAM), biosensors, electronic sensors and optical microcavities. This review deals with the optical and electrical applications of the purple pigment Bacteriorhodopsin.

A simple polymeric model describes cell nuclear mechanical response

NASA Astrophysics Data System (ADS)

Banigan, Edward; Stephens, Andrew; Marko, John

The cell nucleus must continually resist inter- and intracellular mechanical forces, and proper mechanical response is essential to basic cell biological functions as diverse as migration, differentiation, and gene regulation. Experiments probing nuclear mechanics reveal that the nucleus stiffens under strain, leading to two characteristic regimes of force response. This behavior depends sensitively on the intermediate filament protein lamin A, which comprises the outer layer of the nucleus, and the properties of the chromatin interior. To understand these mechanics, we study a simulation model of a polymeric shell encapsulating a semiflexible polymer. This minimalistic model qualitatively captures the typical experimental nuclear force-extension relation and observed nuclear morphologies. Using a Flory-like theory, we explain the simulation results and mathematically estimate the force-extension relation. The model and experiments suggest that chromatin organization is a dominant contributor to nuclear mechanics, while the lamina protects cell nuclei from large deformations.

Extending the Implicit Association Test (IAT): Assessing Consumer Attitudes Based on Multi-Dimensional Implicit Associations

PubMed Central

Gattol, Valentin; Sääksjärvi, Maria; Carbon, Claus-Christian

2011-01-01

Background The authors present a procedural extension of the popular Implicit Association Test (IAT; [1]) that allows for indirect measurement of attitudes on multiple dimensions (e.g., safe–unsafe; young–old; innovative–conventional, etc.) rather than on a single evaluative dimension only (e.g., good–bad). Methodology/Principal Findings In two within-subjects studies, attitudes toward three automobile brands were measured on six attribute dimensions. Emphasis was placed on evaluating the methodological appropriateness of the new procedure, providing strong evidence for its reliability, validity, and sensitivity. Conclusions/Significance This new procedure yields detailed information on the multifaceted nature of brand associations that can add up to a more abstract overall attitude. Just as the IAT, its multi-dimensional extension/application (dubbed md-IAT) is suited for reliably measuring attitudes consumers may not be consciously aware of, able to express, or willing to share with the researcher [2], [3]. PMID:21246037

Bioassay, isolation and studies on the mechanism of action of neurite extension factor

NASA Technical Reports Server (NTRS)

Kligman, D.

1984-01-01

The identification and purification of molecules active in promoting neurite outgrowth requires a sensitive reproducible bioassay. A quantitative bioassay was utilized to purify a neurite extension factor (NEF) based on counting the number of phase bright neurons with processes at least equal to one cell body diameter after 20 hrs. in culture is defined, serum free medium. Using a combination of heat treatment DEAE cellulose chromatography and gel filtration, an acidic protein of M sub r = 75,000 was highly purified. Upon reduction, it yields subunits of M sub r = 37,000. Purified fractions are active half maximally at 100 ng/ml in inducing neurite outgrowth in this bioassay. Currently, monoclonal antibodies to NEF are being produced. Female Balb C mice were immunized with the antigen and fusions with mouse myeloma cells will be performed to yield hybridoma cells.

Rank-preserving regression: a more robust rank regression model against outliers.

PubMed

Chen, Tian; Kowalski, Jeanne; Chen, Rui; Wu, Pan; Zhang, Hui; Feng, Changyong; Tu, Xin M

2016-08-30

Mean-based semi-parametric regression models such as the popular generalized estimating equations are widely used to improve robustness of inference over parametric models. Unfortunately, such models are quite sensitive to outlying observations. The Wilcoxon-score-based rank regression (RR) provides more robust estimates over generalized estimating equations against outliers. However, the RR and its extensions do not sufficiently address missing data arising in longitudinal studies. In this paper, we propose a new approach to address outliers under a different framework based on the functional response models. This functional-response-model-based alternative not only addresses limitations of the RR and its extensions for longitudinal data, but, with its rank-preserving property, even provides more robust estimates than these alternatives. The proposed approach is illustrated with both real and simulated data. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Local tests of gravitation with Gaia observations of Solar System Objects

NASA Astrophysics Data System (ADS)

Hees, Aurélien; Le Poncin-Lafitte, Christophe; Hestroffer, Daniel; David, Pedro

2018-04-01

In this proceeding, we show how observations of Solar System Objects with Gaia can be used to test General Relativity and to constrain modified gravitational theories. The high number of Solar System objects observed and the variety of their orbital parameters associated with the impressive astrometric accuracy will allow us to perform local tests of General Relativity. In this communication, we present a preliminary sensitivity study of the Gaia observations on dynamical parameters such as the Sun quadrupolar moment and on various extensions to general relativity such as the parametrized post-Newtonian parameters, the fifth force formalism and a violation of Lorentz symmetry parametrized by the Standard-Model extension framework. We take into account the time sequences and the geometry of the observations that are particular to Gaia for its nominal mission (5 years) and for an extended mission (10 years).

Ranking of physiotherapeutic evaluation methods as outcome measures of stifle functionality in dogs.

PubMed

Hyytiäinen, Heli K; Mölsä, Sari H; Junnila, Jouni T; Laitinen-Vapaavuori, Outi M; Hielm-Björkman, Anna K

2013-04-08

Various physiotherapeutic evaluation methods are used to assess the functionality of dogs with stifle problems. Neither validity nor sensitivity of these methods has been investigated. This study aimed to determine the most valid and sensitive physiotherapeutic evaluation methods for assessing functional capacity in hind limbs of dogs with stifle problems and to serve as a basis for developing an indexed test for these dogs. A group of 43 dogs with unilateral surgically treated cranial cruciate ligament deficiency and osteoarthritic findings was used to test different physiotherapeutic evaluation methods. Twenty-one healthy dogs served as the control group and were used to determine normal variation in static weight bearing and range of motion.The protocol consisted of 14 different evaluation methods: visual evaluation of lameness, visual evaluation of diagonal movement, visual evaluation of functional active range of motion and difference in thrust of hind limbs via functional tests (sit-to-move and lie-to-move), movement in stairs, evaluation of hind limb muscle atrophy, manual evaluation of hind limb static weight bearing, quantitative measurement of static weight bearing of hind limbs with bathroom scales, and passive range of motion of hind limb stifle (flexion and extension) and tarsal (flexion and extension) joints using a universal goniometer. The results were compared with those from an orthopaedic examination, force plate analysis, radiographic evaluation, and a conclusive assessment. Congruity of the methods was assessed with a combination of three statistical approaches (Fisher's exact test and two differently calculated proportions of agreeing observations), and the components were ranked from best to worst. Sensitivities of all of the physiotherapeutic evaluation methods against each standard were calculated. Evaluation of asymmetry in a sitting and lying position, assessment of muscle atrophy, manual and measured static weight bearing, and measurement of stifle passive range of motion were the most valid and sensitive physiotherapeutic evaluation methods. Ranking of the various physiotherapeutic evaluation methods was accomplished. Several of these methods can be considered valid and sensitive when examining the functionality of dogs with stifle problems.

Ranking of physiotherapeutic evaluation methods as outcome measures of stifle functionality in dogs

PubMed Central

2013-01-01

Background Various physiotherapeutic evaluation methods are used to assess the functionality of dogs with stifle problems. Neither validity nor sensitivity of these methods has been investigated. This study aimed to determine the most valid and sensitive physiotherapeutic evaluation methods for assessing functional capacity in hind limbs of dogs with stifle problems and to serve as a basis for developing an indexed test for these dogs. A group of 43 dogs with unilateral surgically treated cranial cruciate ligament deficiency and osteoarthritic findings was used to test different physiotherapeutic evaluation methods. Twenty-one healthy dogs served as the control group and were used to determine normal variation in static weight bearing and range of motion. The protocol consisted of 14 different evaluation methods: visual evaluation of lameness, visual evaluation of diagonal movement, visual evaluation of functional active range of motion and difference in thrust of hind limbs via functional tests (sit-to-move and lie-to-move), movement in stairs, evaluation of hind limb muscle atrophy, manual evaluation of hind limb static weight bearing, quantitative measurement of static weight bearing of hind limbs with bathroom scales, and passive range of motion of hind limb stifle (flexion and extension) and tarsal (flexion and extension) joints using a universal goniometer. The results were compared with those from an orthopaedic examination, force plate analysis, radiographic evaluation, and a conclusive assessment. Congruity of the methods was assessed with a combination of three statistical approaches (Fisher’s exact test and two differently calculated proportions of agreeing observations), and the components were ranked from best to worst. Sensitivities of all of the physiotherapeutic evaluation methods against each standard were calculated. Results Evaluation of asymmetry in a sitting and lying position, assessment of muscle atrophy, manual and measured static weight bearing, and measurement of stifle passive range of motion were the most valid and sensitive physiotherapeutic evaluation methods. Conclusions Ranking of the various physiotherapeutic evaluation methods was accomplished. Several of these methods can be considered valid and sensitive when examining the functionality of dogs with stifle problems. PMID:23566355

Contrasting influences of Drosophila white/mini-white on ethanol sensitivity in two different behavioral assays

PubMed Central

Chan, Robin F.; Lewellyn, Lara; DeLoyht, Jacqueline M.; Sennett, Kristyn; Coffman, Scarlett; Hewitt, Matthew; Bettinger, Jill C.; Warrick, John M.; Grotewiel, Mike

2014-01-01

Background The fruit fly Drosophila melanogaster has been used extensively to investigate genetic mechanisms of ethanol-related behaviors. Many past studies in flies, including studies from our laboratory, have manipulated gene expression using transposons carrying the genetic-phenotypic marker mini-white, a derivative of the endogenous gene white. Whether the mini-white transgenic marker or the endogenous white gene influence behavioral responses to acute ethanol exposure in flies has not been systematically investigated. Methods We manipulated mini-white and white expression via (i) transposons marked with mini-white, (ii) RNAi against mini-white and white and (iii) a null allele of white. We assessed ethanol sensitivity and tolerance using a previously described eRING assay (based on climbing in the presence of ethanol) and an assay based on ethanol-induced sedation. Results In eRING assays, ethanol-induced impairment of climbing correlated inversely with expression of the mini-white marker from a series of transposon insertions. Additionally, flies harboring a null allele of white or flies with RNAi-mediated knockdown of mini-white were significantly more sensitive to ethanol in eRING assays than controls expressing endogenous white or the mini-white marker. In contrast, ethanol sensitivity and rapid tolerance measured in the ethanol sedation assay were not affected by decreased expression of mini-white or endogenous white in flies. Conclusions Ethanol sensitivity measured in the eRING assay is noticeably influenced by white and mini-white, making eRING problematic for studies on ethanol-related behavior in Drosophila using transgenes marked with mini-white. In contrast, the ethanol sedation assay described here is a suitable behavioral paradigm for studies on ethanol sedation and rapid tolerance in Drosophila including those that use widely available transgenes marked with mini-white. PMID:24890118

Spatial patterns of stream temperatures and electric conductivity in a mesoscale catchment

NASA Astrophysics Data System (ADS)

Lieder, Ernestine; Weiler, Markus; Blume, Theresa

2017-04-01

Stream temperature and electric conductivity (EC) are both relatively easily measured and can provide valuable information on runoff generation processes and catchment storage.This study investigates the spatial variability of stream temperature and EC in a mesoscale basin. We focus on the mesoscale (sub-catchments and reach scale), and long term (seasonal / annual) stream temperature and EC patterns. Our study basin is the Attert catchment in Luxembourg (288km2), which contains multiple sub-catchments of different geology, topography and land use patterns. We installed 90 stream temperature and EC sensors at sites across the basin in summer 2015. The collected data is complemented by land use and discharge data and an extensive climate data set. Thermal sensitivity was calculated as the slope of daily air temperature-water-temperature regression line and describes the sensitivity of stream temperature to long term environmental change. Amplitude sensitivity was calculated as slope of the daily air and water temperature amplitude regression and describes the short term warming capacity of the stream. We found that groups with similar long term thermal and EC patterns are strongly related to different geological units. The sandstone reaches show the coldest temperatures and lowest annual thermal sensitivity to air temperature. The slate reaches are characterized by comparably low EC and high daily temperature amplitudes and amplitude sensitivity. Furthermore, mean annual temperatures and thermal sensitivities increase exponentially with drainage area, which can be attributed to the accumulation of heat throughout the system. On the reach scale, daily stream temperature fluctuations or sensitivities were strongly influenced by land cover distribution, stream shading and runoff volume. Daily thermal sensitivities were low for headwater streams; peaked for intermediate reaches in the middle of the catchment and then decreased again further downstream with increasing drainage area. Combining spatially distributed time series of stream temperatures and EC with information about geology, landscape and climate provides insight into the underlying hydrological processes and allows for the identification of thermally sensitive regions and reaches.

Development of Position-sensitive Transition-edge Sensor X-ray Detectors

NASA Technical Reports Server (NTRS)

Smith, S. J.; Bandler, S. R.; Brekosky, R. P.; Brown, A.-D.; Chervenak, J. A.; Eckard, M. E.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. s.;

Vector magnetometer based on synchronous manipulation of nitrogen-vacancy centers in all crystal directions

NASA Astrophysics Data System (ADS)

Zhang, Chen; Yuan, Heng; Zhang, Ning; Xu, Lixia; Zhang, Jixing; Li, Bo; Fang, Jiancheng

2018-04-01

Negatively charged nitrogen vacancy (NV‑) centers in diamond have been extensively studied as high-sensitivity magnetometers, showcasing a wide range of applications. This study experimentally demonstrates a vector magnetometry scheme based on synchronous manipulation of NV‑ center ensembles in all crystal directions using double frequency microwaves (MWs) and multi-coupled-strip-lines (mCSL) waveguide. The application of the mCSL waveguide ensures a high degree of synchrony (99%) for manipulating NV‑ centers in multiple orientations in a large volume. Manipulation with double frequency MWs makes NV‑ centers of all four crystal directions involved, and additionally leads to an enhancement of the manipulation field. In this work, by monitoring the changes in the slope of the resonance line consisting of multi-axes NV‑ centers, measurement of the direction of the external field vector was demonstrated with a sensitivity of {{10}\\prime}/\\sqrt{Hz} . Based on the scheme, the fluorescence signal contrast was improved by four times higher and the sensitivity to the magnetic field strength was improved by two times. The method provides a more practical way of achieving vector sensors based on NV‑ center ensembles in diamond.

Flare model sensitivity of the Balmer spectrum

NASA Technical Reports Server (NTRS)

Falchi, A.; Falciani, R.; Smaldone, L. A.; Tozzi, G. P.

1989-01-01

Careful studies of various chromospheric spectral signatures are very important in order to explore their possible sensitivity to the modifications of the thermodynamic quantities produced by the flare occurrence. Pioneer work of Canfield and co-workers have shown how the H alpha behavior is able to indicate different changes in the atmospheric parameters structure associated to the flare event. It was decided to study the behavior of the highest Balmer lines and of the Balmer continuum in different solar flare model atmospheres. These spectral features, originating in the deep photosphere in a quiet area, may have a sensitivity different from H alpha to the modification of a flare atmosphere. The details of the method used to compute the Stark profile of the higher Balmer line (n is greater than or equal to 6) and their merging were extensively given elsewhere (Donati-Falchi et al., 1985; Falchi et al., 1989). The models used were developed by Ricchiazzi in his thesis (1982) evaluating the chromospheric response to both the nonthermal electron flux, for energy greater than 20 kev, (F sub 20) and to the thermal conduction, (F sub c). The effect of the coronal pressure values (P sub O) at the apex of the flare loop is also included.

Mirnacle: machine learning with SMOTE and random forest for improving selectivity in pre-miRNA ab initio prediction.

PubMed

Marques, Yuri Bento; de Paiva Oliveira, Alcione; Ribeiro Vasconcelos, Ana Tereza; Cerqueira, Fabio Ribeiro

2016-12-15

MicroRNAs (miRNAs) are key gene expression regulators in plants and animals. Therefore, miRNAs are involved in several biological processes, making the study of these molecules one of the most relevant topics of molecular biology nowadays. However, characterizing miRNAs in vivo is still a complex task. As a consequence, in silico methods have been developed to predict miRNA loci. A common ab initio strategy to find miRNAs in genomic data is to search for sequences that can fold into the typical hairpin structure of miRNA precursors (pre-miRNAs). The current ab initio approaches, however, have selectivity issues, i.e., a high number of false positives is reported, which can lead to laborious and costly attempts to provide biological validation. This study presents an extension of the ab initio method miRNAFold, with the aim of improving selectivity through machine learning techniques, namely, random forest combined with the SMOTE procedure that copes with imbalance datasets. By comparing our method, termed Mirnacle, with other important approaches in the literature, we demonstrate that Mirnacle substantially improves selectivity without compromising sensitivity. For the three datasets used in our experiments, our method achieved at least 97% of sensitivity and could deliver a two-fold, 20-fold, and 6-fold increase in selectivity, respectively, compared with the best results of current computational tools. The extension of miRNAFold by the introduction of machine learning techniques, significantly increases selectivity in pre-miRNA ab initio prediction, which optimally contributes to advanced studies on miRNAs, as the need of biological validations is diminished. Hopefully, new research, such as studies of severe diseases caused by miRNA malfunction, will benefit from the proposed computational tool.

Contrast-enhanced [18F] fluorodeoxyglucose-positron emission tomography-computed tomography as an initial imaging modality in patients presenting with metastatic malignancy of undefined primary origin.

PubMed

Jain, Avani; Srivastava, Madhur Kumar; Pawaskar, Alok Suresh; Shelley, Simon; Elangovan, Indirani; Jain, Hasmukh; Pandey, Somnath; Kalal, Shilpa; Amalachandran, Jaykanth

2015-01-01

To evaluate the advantages of contrast enhanced F-18-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-contrast enhanced CT [CECT]) when used as an initial imaging modality in patients presenting with metastatic malignancy of undefined primary origin (MUO). A total of 243 patients with fine needle aspiration cytology/biopsy proven MUO were included in this prospective study. Patients who were thoroughly evaluated for primary or primary tumor was detected by any other investigation were excluded from the analysis. Totally, 163 patients with pathological diagnosis of malignancy but no apparent sites of the primary tumor were finally selected for analysis. The site of probable primary malignancy suggested by PET-CECT was confirmed by biopsy/follow-up. PET-CECT suggested probable site of primary in 128/163 (78.52%) patients. In 30/35 remaining patients, primary tumor was not detected even after extensive work-up. In 5 patients, where PET-CECT was negative, primary was found on further extensive investigations or follow-up. The sensitivity, specificity, positive predictive value and negative predictive value of the study were 95.76%, 66.67%, 88.28% and 85.71% respectively. F-18 FDG PET-CECT aptly serves the purpose of initial imaging modality owing to high sensitivity, negative and positive predictive value. PET-CECT not only surveys the whole body for the primary malignancy but also stages the disease accurately. Use of contrast improves the diagnostic utility of modality as well as help in staging of the primary tumor. Although benefits of using PET-CECT as initial diagnostic modality are obvious from this study, there is a need for a larger study comparing conventional methods for diagnosing primary in patients with MUO versus PET-CECT.

Genetic variants of FTO influence adiposity, insulin sensitivity, leptin levels, and resting metabolic rate in the Quebec Family Study.

PubMed

Do, Ron; Bailey, Swneke D; Desbiens, Katia; Belisle, Alexandre; Montpetit, Alexandre; Bouchard, Claude; Pérusse, Louis; Vohl, Marie-Claude; Engert, James C

2008-04-01

A genome-wide association study conducted by the Wellcome Trust Case Control Consortium recently associated single nucleotide polymorphisms (SNPs) in the FTO (fatso/fat mass and obesity associated) gene with type 2 diabetes. These associations were shown to be mediated by obesity. Other research groups found similar results in Europeans and Hispanics but not African Americans. The mechanism by which FTO influences obesity and type 2 diabetes is currently unknown. The present study investigated the role of two FTO SNPs (rs17817449 and rs1421085) in adiposity, insulin sensitivity, and body weight regulation, including energy intake and expenditure. We genotyped 908 individuals from the Quebec City metropolitan area that participated in the Quebec Family Study, a long-term study of extensively phenotyped individuals designed to investigate factors involved in adiposity. We found significant associations for both SNPs with several obesity-related phenotypes. In particular, rs17817449 was associated with BMI (P = 0.0014), weight (P = 0.0059), and waist circumference (P = 0.0021) under an additive model. In addition, this FTO SNP influenced fasting insulin (P = 0.011), homeostasis model assessment of insulin resistance (P = 0.038), and an insulin sensitivity index derived from an oral glucose tolerance test (P = 0.0091). Associations were also found with resting metabolic rate (RMR) (P = 0.042) and plasma leptin levels (P = 0.036). Adjustment for BMI abolished the associations with insulin sensitivity, RMR, and plasma leptin levels. These results confirm that genetic variation at the FTO locus contributes to the etiology of obesity, insulin resistance, and increased plasma leptin levels.

Patterns of allergen sensitization and self-reported allergic disease in parents of food allergic children.

PubMed

Makhija, Melanie M; Robison, Rachel G; Caruso, Deanna; Cai, Miao; Wang, Xiaobin; Pongracic, Jacqueline A

2016-10-01

Sensitization in adults has not been extensively studied. To investigate patterns of allergen sensitization in parents of food allergic children and to compare self-report of allergic disease with specific IgE (sIgE) measurements. A total of 1,252 mothers and 1,225 fathers of food allergic children answered standardized questionnaires about demographics, home environment, history of atopic diseases, and food allergy. Skin prick testing and sIgE serum tests were performed to 9 foods and 5 aeroallergens. A total of 66.1% of parents were sensitized to either a food or aeroallergen. Mean sIgE levels were low for all foods tested. A total of 14.5% of mothers and 12.7% of fathers reported current food allergy. Only 28.4% had sensitization to their reported allergen. Fathers had significantly higher rates of sensitization to both foods and aeroallergens (P < .01) than mothers. Logistic regression evaluating predictors of self-reported food allergy revealed statistically significant positive associations in fathers with self-reported asthma, environmental allergy, and eczema. For mothers, significant positive associations were found with environmental allergy and having more than 1 food allergic child. This cohort of parents of food allergic children found higher rates of sensitization to foods and aeroallergens compared with the general population. However, food sIgE levels were low and correlated poorly with self-reported food allergy. Sex differences in sensitization to foods and aeroallergens were seen. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Silver metal nanoparticles study for biomedical and green house applications

NASA Astrophysics Data System (ADS)

Rauwel, E.; Simón-Gracia, L.; Guha, M.; Rauwel, P.; Kuunal, S.; Wragg, D.

2017-02-01

Metallic nanoparticles (MNP) with diameters ranging from 2 to 100nm have received extensive attention during the past decades due to their many potential applications. This paper presents a structural and cytotoxicity study of silver metal nanoparticles targeted towards biomedical applications. Spherical Ag MNPs of diameter from 20 to 50 nm have been synthesized. The encapsulation of Ag MNPs inside pH-sensitive polymersomes has been also studied for the development of biomedical applications. A cytotoxicity study of the Ag MNPs against primary prostatic cancer cell line (PPC-1) has demonstrated a high mortality rate for concentrations ranging from 100 to 200mg/L. The paper will discuss the potential for therapeutic treatments of these Ag MNPs.

Extrinsic polarization-controlled optical anisotropy in plasmon-black phosphorus coupled system

NASA Astrophysics Data System (ADS)

Liu, Zizhuo; Wells, Spencer A.; Butun, Serkan; Palacios, Edgar; Hersam, Mark C.; Aydin, Koray

2018-07-01

Two-dimensional black phosphorus (BP) has drawn extensive research interest due to its promising anisotropic photonic and electronic properties. Here, we study anisotropic optical absorption and photoresponse of exfoliated BP flakes at visible frequencies. We enhance this intrinsic optical anisotropy in BP flakes by coupling plasmonic rectangular nanopatch arrays that support localized surface plasmon resonances. In particular, by combining extrinsic anisotropic plasmonic nanostructures lithographically aligned with intrinsically anisotropic BP flakes, we demonstrate for the first time a combined anisotropic plasmonic-semiconductor coupling that provides significant control over the polarization-dependent optical properties of the plasmon-BP hybrid material system, enhancing polarization-sensitive responses to a larger degree. This hybrid material system not only unveils the plasmon-enhanced mechanisms in BP, but also provides novel controllable functionalities in optoelectronic device applications involving polarization-sensitive optical and electrical responses.

Development of a High Resolution Liquid Xenon Imaging Telescope for Medium Energy Gamma Ray Astrophysics

NASA Technical Reports Server (NTRS)

Aprile, Elena

1992-01-01

In the third year of the research project, we have (1) tested a 3.5 liter prototype of the Liquid Xenon Time Projection Chamber, (2) used a prototype having a 4.4 cm drift gap to study the charge and energy resolution response of the 3.5 liter chamber, (3) obtained an energy resolution as good as that previously measured by us using chambers with drift gaps of the order of millimeters, (4) observed the induction signals produced by MeV gamma rays, (4) used the 20 hybrid charge sensitive preamplifiers for a nondestructive readout of the electron image on the induction wires, (5) performed extensive Monte Carlo simulations to obtain results on efficiency, background rejection capability, and source flux sensitivity, and (6) developed a reconstruction algorithm for events with multiple interaction points.

Extrinsic polarization-controlled optical anisotropy in plasmon-black phosphorus coupled system.

PubMed

Liu, Zizhuo; Wells, Spencer A; Butun, Serkan; Palacios, Edgar; Hersam, Mark C; Aydin, Koray

2018-07-13

Two-dimensional black phosphorus (BP) has drawn extensive research interest due to its promising anisotropic photonic and electronic properties. Here, we study anisotropic optical absorption and photoresponse of exfoliated BP flakes at visible frequencies. We enhance this intrinsic optical anisotropy in BP flakes by coupling plasmonic rectangular nanopatch arrays that support localized surface plasmon resonances. In particular, by combining extrinsic anisotropic plasmonic nanostructures lithographically aligned with intrinsically anisotropic BP flakes, we demonstrate for the first time a combined anisotropic plasmonic-semiconductor coupling that provides significant control over the polarization-dependent optical properties of the plasmon-BP hybrid material system, enhancing polarization-sensitive responses to a larger degree. This hybrid material system not only unveils the plasmon-enhanced mechanisms in BP, but also provides novel controllable functionalities in optoelectronic device applications involving polarization-sensitive optical and electrical responses.

Efficient Flowline Simulations of Ice Shelf-Ocean Interactions: Sensitivity Studies with a Fully Coupled Model

NASA Technical Reports Server (NTRS)

Walker, Ryan Thomas; Holland, David; Parizek, Byron R.; Alley, Richard B.; Nowicki, Sophie M. J.; Jenkins, Adrian

2013-01-01

Thermodynamic flowline and plume models for the ice shelf-ocean system simplify the ice and ocean dynamics sufficiently to allow extensive exploration of parameters affecting ice-sheet stability while including key physical processes. Comparison between geophysically and laboratory-based treatments of ice-ocean interface thermodynamics shows reasonable agreement between calculated melt rates, except where steep basal slopes and relatively high ocean temperatures are present. Results are especially sensitive to the poorly known drag coefficient, highlighting the need for additional field experiments to constrain its value. These experiments also suggest that if the ice-ocean interface near the grounding line is steeper than some threshold, further steepening of the slope may drive higher entrainment that limits buoyancy, slowing the plume and reducing melting; if confirmed, this will provide a stabilizing feedback on ice sheets under some circumstances.

Experimental droughts with rainout shelters: A methodological review

USDA-ARS?s Scientific Manuscript database

Forecast increases in the frequency, intensity and duration of droughts with climate change may have extreme and extensive ecological consequences. There are currently hundreds of published, ongoing and new drought experiments worldwide aimed to assess ecosystem sensitivities to drought and identify...

Workshop Report: Juvenile toxicity testing protocols for chemicals

EPA Science Inventory

There is increased awareness of the specific position of children when it comes to hazards of xenobiotic exposures. Children are not small adults, since their exposure patterns, compound kinetics and metabolism, and sensitivity of their developing organs may differ extensively fr...

Control of Wheel/Rail Noise and Vibration

DOT National Transportation Integrated Search

1982-04-01

An analytical model of the generation of wheel/rail noise has been developed and validated through an extensive series of field tests carried out at the Transportation Test Center using the State of the Art Car. A sensitivity analysis has been perfor...

The Diagnostic Value of Gastrin-17 Detection in Atrophic Gastritis

PubMed Central

Wang, Xu; Ling, Li; Li, Shanshan; Qin, Guiping; Cui, Wei; Li, Xiang; Ni, Hong

2016-01-01

Abstract A meta-analysis was performed to assess the diagnostic value of gastrin-17 (G-17) for the early detection of chronic atrophic gastritis (CAG). An extensive literature search was performed, with the aim of selecting publications that reported the accuracy of G-17 in predicting CAG, in the following databases: PubMed, Science Direct, Web of Science, Chinese Biological Medicine, Chinese National Knowledge Infrastructure, Wanfang, and VIP. To assess the diagnostic value of G-17, the following statistics were estimated and described: sensitivity, specificity, diagnostic odds ratios (DOR), summary receiver operating characteristic curves, area under the curve (AUC), and 95% confidence intervals (CIs). Thirteen studies that met the inclusion criteria were included in this meta-analysis, comprising 894 patients and 1950 controls. The pooled sensitivity and specificity of these studies were 0.48 (95% CI: 0.45–0.51) and 0.79 (95% CI: 0.77–0.81), respectively. The DOR was 5.93 (95% CI: 2.93–11.99), and the AUC was 0.82. G-17 may have potential diagnostic value because it has good specificity and a moderate DOR and AUC for CAG. However, more studies are needed to improve the sensitivity of this diagnostic tool in the future. PMID:27149493

Orbit Transfer Vehicle Engine Study. Phase A, extension 1: Advanced expander cycle engine optimization

NASA Technical Reports Server (NTRS)

Mellish, J. A.

1979-01-01

The performance optimization of expander cycle engines at vacuum thrust levels of 10K, 15K, and 20K lb is discussed. The optimization is conducted for a maximum engine length with an extendible nozzle in the retracted position of 60 inches and an engine mixture ratio of 6.0:1. The thrust chamber geometry and cycle analyses are documented. In addition, the sensitivity of a recommended baseline expander cycle to component performance variations is determined and chilldown/start propellant consumptions are estimated.

RF model of the distribution system as a communication channel, phase 2. Volume 2: Task reports

NASA Technical Reports Server (NTRS)

Rustay, R. C.; Gajjar, J. T.; Rankin, R. W.; Wentz, R. C.; Wooding, R.

1982-01-01

Based on the established feasibility of predicting, via a model, the propagation of Power Line Frequency on radial type distribution feeders, verification studies comparing model predictions against measurements were undertaken using more complicated feeder circuits and situations. Detailed accounts of the major tasks are presented. These include: (1) verification of model; (2) extension, implementation, and verification of perturbation theory; (3) parameter sensitivity; (4) transformer modeling; and (5) compensation of power distribution systems for enhancement of power line carrier communication reliability.

Potential New Lidar Observations for Cloud Studies

NASA Technical Reports Server (NTRS)

Winker, Dave; Hu, Yong; Narir, Amin; Cai, Xia

2015-01-01

The response of clouds to global warming represents a major uncertainty in estimating climate sensitivity. These uncertainties have been tracked to shallow marine clouds in the tropics and subtropics. CALIOP observations have already been used extensively to evaluate model predictions of shallow cloud fraction and top height (Leahy et al. 2013; Nam et al 2012). Tools are needed to probe the lowest levels of the troposphere. The large footprint of satellite lidars gives large multiple scattering from clouds which presents new possibilities for cloud retrievals to constrain model predictions.

Accuracy of Computed Tomography for Predicting Pathologic Nodal Extracapsular Extension in Patients With Head-and-Neck Cancer Undergoing Initial Surgical Resection

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

Prabhu, Roshan S., E-mail: roshansprabhu@gmail.com; Winship Cancer Institute, Emory University, Atlanta, Georgia; Magliocca, Kelly R.

2014-01-01

Purpose: Nodal extracapsular extension (ECE) in patients with head-and-neck cancer increases the loco-regional failure risk and is an indication for adjuvant chemoradiation therapy (CRT). To reduce the risk of requiring trimodality therapy, patients with head-and-neck cancer who are surgical candidates are often treated with definitive CRT when preoperative computed tomographic imaging suggests radiographic ECE. The purpose of this study was to assess the accuracy of preoperative CT imaging for predicting pathologic nodal ECE (pECE). Methods and Materials: The study population consisted of 432 consecutive patients with oral cavity or locally advanced/nonfunctional laryngeal cancer who underwent preoperative CT imaging before initialmore » surgical resection and neck dissection. Specimens with pECE had the extent of ECE graded on a scale from 1 to 4. Results: Radiographic ECE was documented in 46 patients (10.6%), and pECE was observed in 87 (20.1%). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 43.7%, 97.7%, 82.6%, and 87.3%, respectively. The sensitivity of radiographic ECE increased from 18.8% for grade 1 to 2 ECE, to 52.9% for grade 3, and 72.2% for grade 4. Radiographic ECE criteria of adjacent structure invasion was a better predictor than irregular borders/fat stranding for pECE. Conclusions: Radiographic ECE has poor sensitivity, but excellent specificity for pECE in patients who undergo initial surgical resection. PPV and NPV are reasonable for clinical decision making. The performance of preoperative CT imaging increased as pECE grade increased. Patients with resectable head-and-neck cancer with radiographic ECE based on adjacent structure invasion are at high risk for high-grade pECE requiring adjuvant CRT when treated with initial surgery; definitive CRT as an alternative should be considered where appropriate.« less

The Evolution of Gas in Protoplanetary Systems: The Herschel GASPS Open Time Key Programme

NASA Technical Reports Server (NTRS)

Roberge, A.; Dent, W.

2010-01-01

The Gas in Protoplanetary Systems (GASPS) Open Time Key Programme for the Herschel Space Observatory will be the first extensive, systematic survey of gas in circumstellar disks over the critical transition from gas-rich protoplanetary through to gas-poor debris. The brightest spectral lines from disks lie in the far-infrared and arise from radii spanning roughly 10 to 100 AU, where giant planets are expected to form. Herschel is uniquely able to observe this wavelength regime with the sensitivity to allow a large scale survey. We will execute a 2-phase study using the PACS instrument. Phase I is a spectroscopic survey about 250 young stars for fine structure emission lines of [CII] (at 157 microns) and [OI] (at 63 microns). In Phase II, the brightest sources will be followed up with additional PACS spectroscopy ([OI] at 145 microns and some rotational lines of water). We expect that the gas mass sensitivity will be more than an order of magnitude lower than that achieved by ISO and Spitzer or expected for SOFIA. We will also measure the dust continuum to an equivalent mass sensitivity. We will observe several nearby clusters with ages from 1 to 30 Myr, encompassing a wide range of disk masses and stellar luminosities. The sample covers disk evolution from protoplanetary disks through to young debris disks, i.e. the main epoch of planet formation. With this extensive dataset, the GASPS project will: 1) trace gas and dust in the planet formation region across a large multivariate parameter space, 2) provide the first definitive measurement of the gas dissipation timescale in disks, 3) elucidate the evolutionary link between protoplanetary and debris disks, 4) investigate water abundances in the planetforming regions of disks, and 5) provide a huge database of disk observations and models with long-lasting legacy value for follow-up studies.

GenoType® Mtbdrsl assay for resistance to second-line anti-tuberculosis drugs

PubMed Central

Theron, Grant; Peter, Jonny; Richardson, Marty; Warren, Rob; Dheda, Keertan; Steingart, Karen R

2016-01-01

Background Genotype® MTBDRsl (MTBDRsl) is a rapid DNA-based test for detecting specific mutations associated with resistance to fluoroquinolones and second-line injectable drugs (SLIDs) in Mycobacterium tuberculosis complex. MTBDRsl version 2.0 (released in 2015) identifies the mutations detected by version 1.0, as well as additional mutations. The test may be performed on a culture isolate or a patient specimen, which eliminates delays associated with culture. Version 1.0 requires a smear-positive specimen, while version 2.0 may use a smear-positive or -negative specimen. We performed this updated review as part of a World Health Organization process to develop updated guidelines for using MTBDRsl. Objectives To assess and compare the diagnostic accuracy of MTBDRsl for: 1. fluoroquinolone resistance, 2. SLID resistance, and 3. extensively drug-resistant tuberculosis, indirectly on a M. tuberculosis isolate grown from culture or directly on a patient specimen. Participants were people with rifampicin-resistant or multidrug-resistant tuberculosis. The role of MTBDRsl would be as the initial test, replacing culture-based drug susceptibility testing (DST), for detecting second-line drug resistance. Search methods We searched the following databases without language restrictions up to 21 September 2015: the Cochrane Infectious Diseases Group Specialized Register; MEDLINE; Embase OVID; Science Citation Index Expanded, Conference Proceedings Citation Index-Science, and BIOSIS Previews (all three from Web of Science); LILACS; and SCOPUS; registers for ongoing trials; and ProQuest Dissertations & Theses A&I. We reviewed references from included studies and contacted specialists in the field. Selection criteria We included cross-sectional and case-control studies that determined MTBDRsl accuracy against a defined reference standard (culture-based DST, genetic sequencing, or both). Data collection and analysis Two review authors independently extracted data and assessed quality using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We synthesized data for versions 1.0 and 2.0 separately. We estimated MTBDRsl sensitivity and specificity for fluoroquinolone resistance, SLID resistance, and extensively drug-resistant tuberculosis when the test was performed indirectly or directly (smear-positive specimen for version 1.0, smear-positive or -negative specimen for version 2.0). We explored the influence on accuracy estimates of individual drugs within a drug class and of different reference standards. We performed most analyses using a bivariate random-effects model with culture-based DST as reference standard. Main results We included 27 studies. Twenty-six studies evaluated version 1.0, and one study version 2.0. Of 26 studies stating specimen country origin, 15 studies (58%) evaluated patients from low- or middle-income countries. Overall, we considered the studies to be of high methodological quality. However, only three studies (11%) had low risk of bias for the reference standard; these studies used World Health Organization (WHO)-recommended critical concentrations for all drugs in the culture-based DST reference standard. MTBDRsl version 1.0 Fluoroquinolone resistance: indirect testing, MTBDRsl pooled sensitivity and specificity (95% confidence interval (CI)) were 85.6% (79.2% to 90.4%) and 98.5% (95.7% to 99.5%), (19 studies, 2223 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 86.2% (74.6% to 93.0%) and 98.6% (96.9% to 99.4%), (nine studies, 1771 participants, moderate quality evidence). SLID resistance: indirect testing, MTBDRsl pooled sensitivity and specificity were 76.5% (63.3% to 86.0%) and 99.1% (97.3% to 99.7%), (16 studies, 1921 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 87.0% (38.1% to 98.6%) and 99.5% (93.6% to 100.0%), (eight studies, 1639 participants, low quality evidence). Extensively drug-resistant tuberculosis: indirect testing, MTBDRsl pooled sensitivity and specificity were 70.9% (42.9% to 88.8%) and 98.8% (96.1% to 99.6%), (eight studies, 880 participants); direct testing (smear-positive specimen), pooled sensitivity and specificity were 69.4% (38.8% to 89.0%) and 99.4% (95.0% to 99.3%), (six studies, 1420 participants, low quality evidence). Similar to the original Cochrane review, we found no evidence of a significant difference in MTBDRsl version 1.0 accuracy between indirect and direct testing for fluoroquinolone resistance, SLID resistance, and extensively drug-resistant tuberculosis. MTBDRsl version 2.0 Fluoroquinolone resistance: direct testing, MTBDRsl sensitivity and specificity were 97% (83% to 100%) and 98% (93% to 100%), smear-positive specimen; 80% (28% to 99%) and 100% (40% to 100%), smear-negative specimen. SLID resistance: direct testing, MTBDRsl sensitivity and specificity were 89% (72% to 98%) and 90% (84% to 95%), smear-positive specimen; 80% (28% to 99%) and 100% (40% to 100%), smear-negative specimen. Extensively drug-resistant tuberculosis: direct testing, MTBDRsl sensitivity and specificity were 79% (49% to 95%) and 97% (93% to 99%), smear-positive specimen; 50% (1% to 99%) and 100% (59% to 100%), smear-negative specimen. We had insufficient data to estimate summary sensitivity and specificity of version 2.0 (smear-positive and -negative specimens) or to compare accuracy of the two versions. A limitation was that most included studies did not consistently use the World Health Organization (WHO)-recommended concentrations for drugs in the culture-based DST reference standard. Authors' conclusions In people with rifampicin-resistant or multidrug-resistant tuberculosis, MTBDRsl performed on a culture isolate or smear-positive specimen may be useful in detecting second-line drug resistance. MTBDRsl (smear-positive specimen) correctly classified around six in seven people as having fluoroquinolone or SLID resistance, although the sensitivity estimates for SLID resistance varied. The test rarely gave a positive result for people without drug resistance. However, when second-line drug resistance is not detected (MTBDRsl result is negative), conventional DST can still be used to evaluate patients for resistance to the fluoroquinolones or SLIDs. We recommend that future work evaluate MTBDRsl version 2.0, in particular on smear-negative specimens and in different settings to account for different resistance-causing mutations that may vary by strain. Researchers should also consider incorporating WHO-recommended critical concentrations into their culture-based reference standards. PLAIN LANGUAGE SUMMARY The rapid test GenoType® MTBDRsl for testing resistance to second-line TB drugs Background Different drugs are available to treat tuberculosis (TB), but resistance to these drugs is a growing problem. People with drug-resistant TB require second-line TB drugs that, compared with first-line TB drugs, must be taken for longer and may be associated with more harms. Detecting TB drug resistance quickly is important for improving health, reducing deaths, and decreasing the spread of drug-resistant TB. Definitions Multidrug-resistant TB (MDR-TB) is caused by TB bacteria that are resistant to at least isoniazid and rifampicin, the two most potent TB drugs. Extensively drug-resistant TB (XDR-TB) is a type of MDR-TB that is resistant to nearly all TB drugs. What test is evaluated by this review? GenoType® MTBDRsl (MTBDRsl) is a rapid test for detecting resistance to second-line TB drugs. In people with MDR-TB, MTBDRsl is used to detect additional drug resistance. The test may be performed on TB bacteria grown in culture from a patient specimen (indirect testing) or on a patient specimen (direct testing), which eliminates delays associated with culture. MTBDRsl version 1.0 requires a specimen to be smear-positive by microscopy, while version 2.0 (released in 2015) may use a smear-positive or -negative specimen. What are the aims of the review? We wanted to find out how accurate MTBDRsl is for detecting drug resistance; to compare indirect and direct testing; and to compare the two test versions. How up-to-date is the review? We searched for and used studies that had been published up to 21 September 2015. What are the main results of the review? We found 27 studies; 26 studies evaluated MTBDRsl version 1.0 and one study evaluated version 2.0. Fluoroquinolone drugs MTBDRsl version 1.0 (smear-positive specimen) detected 86% of people with fluoroquinolone resistance and rarely gave a positive result for people without resistance (GRADE, moderate quality evidence). Second-line injectable drugs MTBDRsl version 1.0 (smear-positive specimen) detected 87% of people with second-line injectable drug resistance and rarely gave a positive result for people without resistance (GRADE, low quality evidence). XDR-TB MTBDRsl version 1.0 (smear-positive specimen) detected 69% of people with XDR-TB and rarely gave a positive result for people without resistance (GRADE, low quality evidence). For MTBDRsl version 1.0, we found similar results for indirect and direct testing (smear-positive specimen). As we identified only one study evaluating MTBDRsl version 2.0, we could not be sure of the diagnostic accuracy of version 2.0. Also, we could not compare accuracy of the two versions. What is the methodological quality of the evidence? We used the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool to assess study quality. Overall, we considered the included studies to be of high quality; however, we had concerns about how the reference standard (the benchmark against which MTBDRsl was measured) was applied. What are the authors' conclusions? MTBDRsl (smear-positive specimen) identified most of the patients with second-line drug resistance. When the test reports a negative result, conventional testing for drug resistance can still be used. PMID:27605387

Super-soliton dust-acoustic waves in four-component dusty plasma using non-extensive electrons and ions distributions

NASA Astrophysics Data System (ADS)

El-Wakil, S. A.; Abulwafa, Essam M.; Elhanbaly, Atalla A.

2017-07-01

Based on Sagdeev pseudo-potential and phase-portrait, the dynamics of four-component dust plasma with non-extensively distributed electrons and ions are investigated. Three distinct types of nonlinear waves, namely, soliton, double layer, and super-soliton, have been found. The basic features of such waves are high sensitivity to Mach number, non-extensive parameter, and dust temperature ratio. It is found that the multi-component plasma is a necessary condition for super-soliton's existence, having a wider amplitude and a larger width than the regular soliton. Super-solitons may also exist when the Sagdeev pseudo-potential curves admit at least four extrema and two roots. In our multi-component plasma system, the super-solitons can be found by increasing the Mach number and the non-extensive parameter beyond those of double-layers. On the contrary, the super-soliton can be produced by decreasing the dust temperature ratio. The conditions of the onset of such nonlinear waves and its merging to regular solitons have been studied. This work shows that the obtained nonlinear waves are found to exist only in the super-sonic Mach number regime. The obtained results may be of wide relevance in the field of space plasma and may also be helpful to better understand the nonlinear fluctuations in the Auroral-zone of the Earth's magnetosphere.

Nanoparticle Enhancement Cascade for Sensitive Multiplex Measurements of Biomarkers in Complex Fluids with Surface Plasmon Resonance Imaging.

PubMed

Hendriks, Jan; Stojanovic, Ivan; Schasfoort, Richard B M; Saris, Daniël B F; Karperien, Marcel

2018-06-05

There is a large unmet need for reliable biomarker measurement systems for clinical application. Such systems should meet challenging requirements for large scale use, including a large dynamic detection range, multiplexing capacity, and both high specificity and sensitivity. More importantly, these requirements need to apply to complex biological samples, which require extensive quality control. In this paper, we present the development of an enhancement detection cascade for surface plasmon resonance imaging (SPRi). The cascade applies an antibody sandwich assay, followed by neutravidin and a gold nanoparticle enhancement for quantitative biomarker measurements in small volumes of complex fluids. We present a feasibility study both in simple buffers and in spiked equine synovial fluid with four cytokines, IL-1β, IL-6, IFN-γ, and TNF-α. Our enhancement cascade leads to an antibody dependent improvement in sensitivity up to 40 000 times, resulting in a limit of detection as low as 50 fg/mL and a dynamic detection range of more than 7 logs. Additionally, measurements at these low concentrations are highly reliable with intra- and interassay CVs between 2% and 20%. We subsequently showed this assay is suitable for multiplex measurements with good specificity and limited cross-reactivity. Moreover, we demonstrated robust detection of IL-6 and IL-1β in spiked undiluted equine synovial fluid with small variation compared to buffer controls. In addition, the availability of real time measurements provides extensive quality control opportunities, essential for clinical applications. Therefore, we consider this method is suitable for broad application in SPRi for multiplex biomarker detection in both research and clinical settings.

Sensitivity of subject-specific models to Hill muscle-tendon model parameters in simulations of gait.

PubMed

Carbone, V; van der Krogt, M M; Koopman, H F J M; Verdonschot, N

2016-06-14

Subject-specific musculoskeletal (MS) models of the lower extremity are essential for applications such as predicting the effects of orthopedic surgery. We performed an extensive sensitivity analysis to assess the effects of potential errors in Hill muscle-tendon (MT) model parameters for each of the 56 MT parts contained in a state-of-the-art MS model. We used two metrics, namely a Local Sensitivity Index (LSI) and an Overall Sensitivity Index (OSI), to distinguish the effect of the perturbation on the predicted force produced by the perturbed MT parts and by all the remaining MT parts, respectively, during a simulated gait cycle. Results indicated that sensitivity of the model depended on the specific role of each MT part during gait, and not merely on its size and length. Tendon slack length was the most sensitive parameter, followed by maximal isometric muscle force and optimal muscle fiber length, while nominal pennation angle showed very low sensitivity. The highest sensitivity values were found for the MT parts that act as prime movers of gait (Soleus: average OSI=5.27%, Rectus Femoris: average OSI=4.47%, Gastrocnemius: average OSI=3.77%, Vastus Lateralis: average OSI=1.36%, Biceps Femoris Caput Longum: average OSI=1.06%) and hip stabilizers (Gluteus Medius: average OSI=3.10%, Obturator Internus: average OSI=1.96%, Gluteus Minimus: average OSI=1.40%, Piriformis: average OSI=0.98%), followed by the Peroneal muscles (average OSI=2.20%) and Tibialis Anterior (average OSI=1.78%) some of which were not included in previous sensitivity studies. Finally, the proposed priority list provides quantitative information to indicate which MT parts and which MT parameters should be estimated most accurately to create detailed and reliable subject-specific MS models. Copyright © 2016 Elsevier Ltd. All rights reserved.

PRISMA-Children (C) and PRISMA-Protocol for Children (P-C) Extensions: a study protocol for the development of guidelines for the conduct and reporting of systematic reviews and meta-analyses of newborn and child health research.

PubMed

Kapadia, Mufiza Z; Askie, Lisa; Hartling, Lisa; Contopoulos-Ioannidis, Despina; Bhutta, Zulfiqar A; Soll, Roger; Moher, David; Offringa, Martin

2016-04-18

Paediatric systematic reviews differ from adult systematic reviews in several key aspects such as considerations of child tailored interventions, justifiable comparators, valid outcomes and child sensitive search strategies. Available guidelines, including PRISMA-P (2015) and PRISMA (2009), do not cover all the complexities associated with reporting systematic reviews in the paediatric population. Using a collaborative, multidisciplinary structure, we aim to develop evidence-based and consensus-based PRISMA-P-C (Protocol for Children) and PRISMA-C (Children) Extensions to guide paediatric systematic review protocol and completed review reporting. This project's methodology follows published recommendations for developing reporting guidelines and involves the following six phases; (1) establishment of a steering committee representing key stakeholder groups; (2) a scoping review to identify potential Extension items; (3) three types of consensus activities including meetings of the steering committee to achieve high-level decisions on the content and methodology of the Extensions, a survey of key stakeholders to generate a list of possible items to include in the Extensions and a formal consensus meeting to select the reporting items to add to, or modify for, the Extension; (4) the preliminary checklist items generated in phase III will be evaluated against the existing evidence and reporting practices in paediatric systematic reviews; (5) extension statements and explanation and elaboration documents will provide detailed advice for each item and examples of good reporting; (6) development and implementation of effective knowledge translation of the extension checklist, and an evaluation of the Extensions by key stakeholders. This protocol was considered a quality improvement project by the Hospital for Sick Children's Ethics Committee and did not require ethical review. The resultant checklists, jointly developed with all relevant stakeholders, will be disseminated through peer-reviewed journals as well as national and international conference presentations. Endorsement of the checklist will be sought simultaneously in multiple journals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

PRISMA-Children (C) and PRISMA-Protocol for Children (P-C) Extensions: a study protocol for the development of guidelines for the conduct and reporting of systematic reviews and meta-analyses of newborn and child health research

PubMed Central

Kapadia, Mufiza Z; Askie, Lisa; Hartling, Lisa; Contopoulos-Ioannidis, Despina; Bhutta, Zulfiqar A; Soll, Roger; Moher, David; Offringa, Martin

2016-01-01

Introduction Paediatric systematic reviews differ from adult systematic reviews in several key aspects such as considerations of child tailored interventions, justifiable comparators, valid outcomes and child sensitive search strategies. Available guidelines, including PRISMA-P (2015) and PRISMA (2009), do not cover all the complexities associated with reporting systematic reviews in the paediatric population. Using a collaborative, multidisciplinary structure, we aim to develop evidence-based and consensus-based PRISMA-P-C (Protocol for Children) and PRISMA-C (Children) Extensions to guide paediatric systematic review protocol and completed review reporting. Methods and analysis This project's methodology follows published recommendations for developing reporting guidelines and involves the following six phases; (1) establishment of a steering committee representing key stakeholder groups; (2) a scoping review to identify potential Extension items; (3) three types of consensus activities including meetings of the steering committee to achieve high-level decisions on the content and methodology of the Extensions, a survey of key stakeholders to generate a list of possible items to include in the Extensions and a formal consensus meeting to select the reporting items to add to, or modify for, the Extension; (4) the preliminary checklist items generated in phase III will be evaluated against the existing evidence and reporting practices in paediatric systematic reviews; (5) extension statements and explanation and elaboration documents will provide detailed advice for each item and examples of good reporting; (6) development and implementation of effective knowledge translation of the extension checklist, and an evaluation of the Extensions by key stakeholders. Ethics and Dissemination This protocol was considered a quality improvement project by the Hospital for Sick Children's Ethics Committee and did not require ethical review. The resultant checklists, jointly developed with all relevant stakeholders, will be disseminated through peer-reviewed journals as well as national and international conference presentations. Endorsement of the checklist will be sought simultaneously in multiple journals. PMID:27091820

A multiplex method for detection of glucose-6-phosphate dehydrogenase (G6PD) gene mutations.

PubMed

Zhang, L; Yang, Y; Liu, R; Li, Q; Yang, F; Ma, L; Liu, H; Chen, X; Yang, Z; Cui, L; He, Y

2015-12-01

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect caused by G6PD gene mutations. This study aimed to develop a cost-effective, multiplex, genotyping method for detecting common mutations in the G6PD gene. We used a SNaPshot approach to genotype multiple G6PD mutations that are common to human populations in South-East Asia. This assay is based on multiplex PCR coupled with primer extension reactions. Different G6PD gene mutations were determined by peak retention time and colors of the primer extension products. We designed PCR primers for multiplex amplification of the G6PD gene fragments and for primer extension reactions to genotype 11 G6PD mutations. DNA samples from a total of 120 unrelated G6PD-deficient individuals from the China-Myanmar border area were used to establish and validate this method. Direct sequencing of the PCR products demonstrated 100% concordance between the SNaPshot and the sequencing results. The SNaPshot method offers a specific and sensitive alternative for simultaneously interrogating multiple G6PD mutations. © 2015 John Wiley & Sons Ltd.

A Model for Growth of a Single Fungal Hypha Based on Well-Mixed Tanks in Series: Simulation of Nutrient and Vesicle Transport in Aerial Reproductive Hyphae

PubMed Central

Balmant, Wellington; Sugai-Guérios, Maura Harumi; Coradin, Juliana Hey; Krieger, Nadia; Furigo Junior, Agenor; Mitchell, David Alexander

2015-01-01

Current models that describe the extension of fungal hyphae and development of a mycelium either do not describe the role of vesicles in hyphal extension or do not correctly describe the experimentally observed profile for distribution of vesicles along the hypha. The present work uses the n-tanks-in-series approach to develop a model for hyphal extension that describes the intracellular transport of nutrient to a sub-apical zone where vesicles are formed and then transported to the tip, where tip extension occurs. The model was calibrated using experimental data from the literature for the extension of reproductive aerial hyphae of three different fungi, and was able to describe different profiles involving acceleration and deceleration of the extension rate. A sensitivity analysis showed that the supply of nutrient to the sub-apical vesicle-producing zone is a key factor influencing the rate of extension of the hypha. Although this model was used to describe the extension of a single reproductive aerial hypha, the use of the n-tanks-in-series approach to representing the hypha means that the model has the flexibility to be extended to describe the growth of other types of hyphae and the branching of hyphae to form a complete mycelium. PMID:25785863

Plasmonic light-sensitive skins of nanocrystal monolayers

NASA Astrophysics Data System (ADS)

Akhavan, Shahab; Gungor, Kivanc; Mutlugun, Evren; Demir, Hilmi Volkan

2013-04-01

We report plasmonically coupled light-sensitive skins of nanocrystal monolayers that exhibit sensitivity enhancement and spectral range extension with plasmonic nanostructures embedded in their photosensitive nanocrystal platforms. The deposited plasmonic silver nanoparticles of the device increase the optical absorption of a CdTe nanocrystal monolayer incorporated in the device. Controlled separation of these metallic nanoparticles in the vicinity of semiconductor nanocrystals enables optimization of the photovoltage buildup in the proposed nanostructure platform. The enhancement factor was found to depend on the excitation wavelength. We observed broadband sensitivity improvement (across 400-650 nm), with a 2.6-fold enhancement factor around the localized plasmon resonance peak. The simulation results were found to agree well with the experimental data. Such plasmonically enhanced nanocrystal skins hold great promise for large-area UV/visible sensing applications.

77 FR 14367 - Agency Information Collection Activities: Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-09

.... SUPPLEMENTARY INFORMATION: Proposal to request approval from OMB of the extension for three years, with revision...: 12 U.S.C. 3105(c)(2), 1817(a)(1) and (3), and 3102(b). Except for select sensitive items, the FFIEC...

Detection of brain tumor margins using optical coherence tomography

NASA Astrophysics Data System (ADS)

Juarez-Chambi, Ronald M.; Kut, Carmen; Rico-Jimenez, Jesus; Campos-Delgado, Daniel U.; Quinones-Hinojosa, Alfredo; Li, Xingde; Jo, Javier

2018-02-01

In brain cancer surgery, it is critical to achieve extensive resection without compromising adjacent healthy, noncancerous regions. Various technological advances have made major contributions in imaging, including intraoperative magnetic imaging (MRI) and computed tomography (CT). However, these technologies have pros and cons in providing quantitative, real-time and three-dimensional (3D) continuous guidance in brain cancer detection. Optical Coherence Tomography (OCT) is a non-invasive, label-free, cost-effective technique capable of imaging tissue in three dimensions and real time. The purpose of this study is to reliably and efficiently discriminate between non-cancer and cancerinfiltrated brain regions using OCT images. To this end, a mathematical model for quantitative evaluation known as the Blind End-Member and Abundances Extraction method (BEAE). This BEAE method is a constrained optimization technique which extracts spatial information from volumetric OCT images. Using this novel method, we are able to discriminate between cancerous and non-cancerous tissues and using logistic regression as a classifier for automatic brain tumor margin detection. Using this technique, we are able to achieve excellent performance using an extensive cross-validation of the training dataset (sensitivity 92.91% and specificity 98.15%) and again using an independent, blinded validation dataset (sensitivity 92.91% and specificity 86.36%). In summary, BEAE is well-suited to differentiate brain tissue which could support the guiding surgery process for tissue resection.

Detection of brain tumor margins using optical coherence tomography

NASA Astrophysics Data System (ADS)

Juarez-Chambi, Ronald M.; Kut, Carmen; Rico-Jimenez, Jesus; Campos-Delgado, Daniel U.; Quinones-Hinojosa, Alfredo; Li, Xingde; Jo, Javier

2018-02-01

In brain cancer surgery, it is critical to achieve extensive resection without compromising adjacent healthy, non-cancerous regions. Various technological advances have made major contributions in imaging, including intraoperative magnetic imaging (MRI) and computed tomography (CT). However, these technologies have pros and cons in providing quantitative, real-time and three-dimensional (3D) continuous guidance in brain cancer detection. Optical Coherence Tomography (OCT) is a non-invasive, label-free, cost-effective technique capable of imaging tissue in three dimensions and real time. The purpose of this study is to reliably and efficiently discriminate between non-cancer and cancer-infiltrated brain regions using OCT images. To this end, a mathematical model for quantitative evaluation known as the Blind End- Member and Abundances Extraction method (BEAE). This BEAE method is a constrained optimization technique which extracts spatial information from volumetric OCT images. Using this novel method, we are able to discriminate between cancerous and non-cancerous tissues and using logistic regression as a classifier for automatic brain tumor margin detection. Using this technique, we are able to achieve excellent performance using an extensive cross-validation of the training dataset (sensitivity 92.91% and specificity 98.15%) and again using an independent, blinded validation dataset (sensitivity 92.91% and specificity 86.36%). In summary, BEAE is well-suited to differentiate brain tissue which could support the guiding surgery process for tissue resection.

Dakota, a multilevel parallel object-oriented framework for design optimization, parameter estimation, uncertainty quantification, and sensitivity analysis version 6.0 theory manual

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

Adams, Brian M.; Ebeida, Mohamed Salah; Eldred, Michael S

The Dakota (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a exible and extensible interface between simulation codes and iterative analysis methods. Dakota contains algorithms for optimization with gradient and nongradient-based methods; uncertainty quanti cation with sampling, reliability, and stochastic expansion methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. By employing object-oriented design to implement abstractions of the key components requiredmore » for iterative systems analyses, the Dakota toolkit provides a exible and extensible problem-solving environment for design and performance analysis of computational models on high performance computers. This report serves as a theoretical manual for selected algorithms implemented within the Dakota software. It is not intended as a comprehensive theoretical treatment, since a number of existing texts cover general optimization theory, statistical analysis, and other introductory topics. Rather, this manual is intended to summarize a set of Dakota-related research publications in the areas of surrogate-based optimization, uncertainty quanti cation, and optimization under uncertainty that provide the foundation for many of Dakota's iterative analysis capabilities.« less

A Liver-Centric Multiscale Modeling Framework for Xenobiotics.

PubMed

Sluka, James P; Fu, Xiao; Swat, Maciej; Belmonte, Julio M; Cosmanescu, Alin; Clendenon, Sherry G; Wambaugh, John F; Glazier, James A

2016-01-01

We describe a multi-scale, liver-centric in silico modeling framework for acetaminophen pharmacology and metabolism. We focus on a computational model to characterize whole body uptake and clearance, liver transport and phase I and phase II metabolism. We do this by incorporating sub-models that span three scales; Physiologically Based Pharmacokinetic (PBPK) modeling of acetaminophen uptake and distribution at the whole body level, cell and blood flow modeling at the tissue/organ level and metabolism at the sub-cellular level. We have used standard modeling modalities at each of the three scales. In particular, we have used the Systems Biology Markup Language (SBML) to create both the whole-body and sub-cellular scales. Our modeling approach allows us to run the individual sub-models separately and allows us to easily exchange models at a particular scale without the need to extensively rework the sub-models at other scales. In addition, the use of SBML greatly facilitates the inclusion of biological annotations directly in the model code. The model was calibrated using human in vivo data for acetaminophen and its sulfate and glucuronate metabolites. We then carried out extensive parameter sensitivity studies including the pairwise interaction of parameters. We also simulated population variation of exposure and sensitivity to acetaminophen. Our modeling framework can be extended to the prediction of liver toxicity following acetaminophen overdose, or used as a general purpose pharmacokinetic model for xenobiotics.

A Liver-Centric Multiscale Modeling Framework for Xenobiotics

PubMed Central

Swat, Maciej; Cosmanescu, Alin; Clendenon, Sherry G.; Wambaugh, John F.; Glazier, James A.

2016-01-01

We describe a multi-scale, liver-centric in silico modeling framework for acetaminophen pharmacology and metabolism. We focus on a computational model to characterize whole body uptake and clearance, liver transport and phase I and phase II metabolism. We do this by incorporating sub-models that span three scales; Physiologically Based Pharmacokinetic (PBPK) modeling of acetaminophen uptake and distribution at the whole body level, cell and blood flow modeling at the tissue/organ level and metabolism at the sub-cellular level. We have used standard modeling modalities at each of the three scales. In particular, we have used the Systems Biology Markup Language (SBML) to create both the whole-body and sub-cellular scales. Our modeling approach allows us to run the individual sub-models separately and allows us to easily exchange models at a particular scale without the need to extensively rework the sub-models at other scales. In addition, the use of SBML greatly facilitates the inclusion of biological annotations directly in the model code. The model was calibrated using human in vivo data for acetaminophen and its sulfate and glucuronate metabolites. We then carried out extensive parameter sensitivity studies including the pairwise interaction of parameters. We also simulated population variation of exposure and sensitivity to acetaminophen. Our modeling framework can be extended to the prediction of liver toxicity following acetaminophen overdose, or used as a general purpose pharmacokinetic model for xenobiotics. PMID:27636091

The thin-layer agar method for direct phenotypic detection of multi- and extensively drug-resistant tuberculosis.

PubMed

Ardizzoni, E; Mulders, W; Kotrikadze, T; Aspindzelashvili, R; Goginashvili, L; Pangtey, H; Varaine, F; Bastard, M; Rigouts, L; de Jong, B C

2015-12-01

Molecular techniques rapidly detect resistance to rifampicin (RMP) and isoniazid (INH), but do not eliminate the need for culture-based drug susceptibility testing (DST) against other drugs. The thin-layer agar (TLA) test, a non-commercial direct DST method, has demonstrated good performance for INH and RMP; however, evidence is still limited, and its applicability for DST of ofloxacin (OFX) and kanamycin (KM) is unknown. We compared 279 TLA DST results with those of MGIT for INH and RMP, and 280 results for OFX and KM with those of the 7H11 agar proportion method, obtained from 320 smear-positive samples from 165 Georgian TB patients. Discrepancies were solved by comparison with a composite reference standard. The prevalence of multidrug-resistant tuberculosis (TB) was 30 of 164 patients (18.3%), 2 (6.7%) of whom had extensively drug-resistant TB. TLA showed 94.7%, 98.2%, 100% and 78.9% sensitivity, respectively, for INH, RMP, OFX and KM, with 100% specificity. Average time to results was 7 days in TLA, 23 in MGIT and 49 for 7H11 agar. In low-resource settings, TLA can be applied for the rapid detection of resistance to INH, RMP and fluoroquinolones. Further studies are necessary to improve sensitivity to KM and further assess its performance for OFX and other drugs and its applicability in field conditions.

Tuning support vector machines for minimax and Neyman-Pearson classification.

PubMed

Davenport, Mark A; Baraniuk, Richard G; Scott, Clayton D

2010-10-01

This paper studies the training of support vector machine (SVM) classifiers with respect to the minimax and Neyman-Pearson criteria. In principle, these criteria can be optimized in a straightforward way using a cost-sensitive SVM. In practice, however, because these criteria require especially accurate error estimation, standard techniques for tuning SVM parameters, such as cross-validation, can lead to poor classifier performance. To address this issue, we first prove that the usual cost-sensitive SVM, here called the 2C-SVM, is equivalent to another formulation called the 2nu-SVM. We then exploit a characterization of the 2nu-SVM parameter space to develop a simple yet powerful approach to error estimation based on smoothing. In an extensive experimental study, we demonstrate that smoothing significantly improves the accuracy of cross-validation error estimates, leading to dramatic performance gains. Furthermore, we propose coordinate descent strategies that offer significant gains in computational efficiency, with little to no loss in performance.

Additional EIPC Study Analysis. Final Report

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

Hadley, Stanton W; Gotham, Douglas J.; Luciani, Ralph L.

Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations weremore » developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 14 topics was developed for further analysis. This paper brings together the earlier interim reports of the first 13 topics plus one additional topic into a single final report.« less

Surface-Accelerated Decomposition of δ-HMX.

PubMed

Sharia, Onise; Tsyshevsky, Roman; Kuklja, Maija M

2013-03-07

Despite extensive efforts to study the explosive decomposition of HMX, a cyclic nitramine widely used as a solid fuel, explosive, and propellant, an understanding of the physicochemical processes, governing the sensitivity of condensed HMX to detonation initiation is not yet achieved. Experimental and theoretical explorations of the initiation of chemistry are equally challenging because of many complex parallel processes, including the β-δ phase transition and the decomposition from both phases. Among four known polymorphs, HMX is produced in the most stable β-phase, which transforms into the most reactive δ-phase under heat or pressure. In this study, the homolytic NO2 loss and HONO elimination precursor reactions of the gas-phase, ideal crystal, and the (100) surface of δ-HMX are explored by first principles modeling. Our calculations revealed that the high sensitivity of δ-HMX is attributed to interactions of surfaces and molecular dipole moments. While both decomposition reactions coexist, the exothermic HONO-isomer formation catalyzes the N-NO2 homolysis, leading to fast violent explosions.

Manned geosynchronous mission requirements and systems analysis study extension

NASA Technical Reports Server (NTRS)

1981-01-01

Turnaround requirements for the manned orbital transfer vehicle (MOTV) baseline and alternate concepts with and without a space operations center (SOC) are defined. Manned orbital transfer vehicle maintenance, refurbishment, resupply, and refueling are considered as well as the most effective combination of ground based and space based turnaround activities. Ground and flight operations requirements for abort are identified as well as low cost approaches to space and ground operations through maintenance and missions sensitivity studies. The recommended turnaround mix shows that space basing MOTV at SOC with periodic return to ground for overhaul results in minimum recurring costs. A pressurized hangar at SOC reduces labor costs by approximately 50%.

Time-resolved circular dichroism: Application to the study of conformal changes in biomolecules

NASA Astrophysics Data System (ADS)

Hache, F.

2010-06-01

Circular dichroism (CD) is known to be a very sensitive probe of the conformation of molecules and biomolecules. It is therefore tempting to implement CD in a pump-probe experiment in order to measure ultrarapid conformational changes which occur in photochemical processes. We present two technical developments of such time-resolved CD experiments. The first one relies on the modulation of the probe polarization from left to right circular whereas the second one measures the pump-induced ellipticity of the probe with a Babinet-Soleil compensator. Some applications are described and extension of these techniques towards the study of elementary protein folding processes is discussed.

Criteria To Screen for Chronic Sinonasal Disease

PubMed Central

Dixon, Anne E.; Sugar, Elizabeth A.; Zinreich, S. James; Slavin, Raymond G.; Corren, Jonathan; Naclerio, Robert M.; Ishii, Masaru; Cohen, Rubin I.; Brown, Ellen D.; Wise, Robert A.; Irvin, Charles G.

2009-01-01

Background: Sinusitis and rhinitis are associated with uncontrolled asthma. There are no simple, validated tools to screen for these diseases. The objective of this study was to assess instruments to assist in the diagnosis of chronic sinonasal disease. Methods: Participants without acute sinonasal symptoms underwent an extensive evaluation. The results were submitted to an expert panel that used the Delphi method to achieve consensus. Using the consensus diagnosis of the panel, we determined the sensitivity and specificity of test procedures to diagnose chronic sinonasal disease. We determined the reproducibility of the most sensitive and specific instrument in a separate cohort. Results: Fifty-nine participants were evaluated, and the expert panel reached consensus for all (42 participants with chronic sinonasal disease, 17 participants without chronic sinonasal disease). A six-item questionnaire based on the frequency of nasal symptoms was the most sensitive tool used to diagnose sinonasal disease (minimum specificity, 0.90). Reproducibility testing in a separate cohort of 63 participants (41 chronic sinonasal disease with asthma, 22 chronic sinonasal disease without asthma) showed a concordance correlation coefficient of 0.91 (95% CI, 0.85 to 0.94) when this questionnaire was limited to five items (ie, excluding a question on smell). This five-item questionnaire had a sensitivity of 0.90 (95% CI, 0.77 to 0.97), a specificity of 0.94 (95% CI, 0.71 to 1.00), and an area under the receiver operating characteristic curve of 0.97 (95% CI, 0.93 to 1.0). Sinus CT scans and nasal endoscopy lacked sensitivity for use in the diagnosis of chronic sinonasal disease. Conclusions: We have developed a sensitive, specific, and reproducible instrument to screen for chronic sinonasal disease. Validation studies of this five-item questionnaire are needed, including in patients with asthma. PMID:19581356

Ultrafast dynamics in co-sensitized photocatalysts under visible and NIR light irradiation.

PubMed

Patwari, Jayita; Chatterjee, Arka; Sardar, Samim; Lemmens, Peter; Pal, Samir Kumar

2018-04-18

Co-sensitization to achieve a broad absorption window is a widely accepted technique in light harvesting nanohybrid synthesis. Protoporphyrin (PPIX) and squaraine (SQ2) are two organic sensitizers absorbing in the visible and NIR wavelength regions of the solar spectrum, respectively. In the present study, we have sensitized zinc oxide (ZnO) nanoparticles using PPIX and SQ2 simultaneously for their potential use in broad-band solar light harvesting in photocatalysis. Förster resonance energy transfer (FRET) from PPIX to SQ2 in close proximity to the ZnO surface has been found to enhance visible light photocatalysis. In order to confirm the effect of intermolecular FRET in photocatalysis, the excited state lifetime of the energy donor dye PPIX has been modulated by inserting d10 (ZnII) and d7 (CoII) metal ions in the central position of the dye (PP(Zn) and PP(Co)). In the case of PP(Co)-SQ2, extensive photo-induced ligand to metal charge transfer counteracts the FRET efficiency while efficient FRET has been observed for the PP(Zn)-SQ2 pair. This observation has been justified by the comparison of the visible light photocatalysis of the respective nanohybrids with several control studies. We have also investigated the NIR photocatalysis of the co-sensitized nanohybrids which reveals that reduced aggregation of SQ2 due to co-sensitization of PPIX increases the NIR photocatalysis. However, core-metalation of PPIX reduces the NIR photocatalytic efficacy, most probably due to excited state charge transfer from SQ2 to the metal centre of PP(Co)/PP(Zn) through the conduction band of the host ZnO nanoparticles.

Accelerator mass spectrometry in biomedical dosimetry: relationship between low-level exposure and covalent binding of heterocyclic amine carcinogens to DNA.

PubMed Central

Turteltaub, K W; Felton, J S; Gledhill, B L; Vogel, J S; Southon, J R; Caffee, M W; Finkel, R C; Nelson, D E; Proctor, I D; Davis, J C

1990-01-01

Accelerator mass spectrometry (AMS) is used to determine the amount of carcinogen covalently bound to mouse liver DNA (DNA adduct) following very low-level exposure to a 14C-labeled carcinogen. AMS is a highly sensitive method for counting long-lived but rare cosmogenic isotopes. While AMS is a tool of importance in the earth sciences, it has not been applied in biomedical research. The ability of AMS to assay rare isotope concentrations (10Be, 14C, 26Al, 41Ca, and 129I) in microgram amounts suggests that extension to the biomedical sciences is a natural and potentially powerful application of the technology. In this study, the relationship between exposure to low levels of 2-amino-3,8-dimethyl[2-14C]imidazo[4,5-f]quinoxaline and formation of DNA adducts is examined to establish the dynamic range of the technique and the potential sensitivity for biological measurements, as well as to evaluate the relationship between DNA adducts and low-dose carcinogen exposure. Instrument reproducibility in this study is 2%; sensitivity is 1 adduct per 10(11) nucleotides. Formation of adducts is linearly dependent on dose down to an exposure of 500 ng per kg of body weight. With the present measurements, we demonstrate at least 1 order of magnitude improvement over the best adduct detection sensitivity reported to date and 3-5 orders of magnitude improvement over other methods used for adduct measurement. An additional improvement of 2 orders of magnitude in sensitivity is suggested by preliminary experiments to develop bacterial hosts depleted in radiocarbon. Expanded applications involving human subjects, including clinical applications, are now expected because of the great detection sensitivity and small sample size requirements of AMS. PMID:2371271

A Retrospective Performance Assessment of the Developmental Neurotoxicity Study in Support of OECD Test Guideline 426

PubMed Central

Makris, Susan L.; Raffaele, Kathleen; Allen, Sandra; Bowers, Wayne J.; Hass, Ulla; Alleva, Enrico; Calamandrei, Gemma; Sheets, Larry; Amcoff, Patric; Delrue, Nathalie; Crofton, Kevin M.

2009-01-01

Objective We conducted a review of the history and performance of developmental neurotoxicity (DNT) testing in support of the finalization and implementation of Organisation of Economic Co-operation and Development (OECD) DNT test guideline 426 (TG 426). Information sources and analysis In this review we summarize extensive scientific efforts that form the foundation for this testing paradigm, including basic neurotoxicology research, interlaboratory collaborative studies, expert workshops, and validation studies, and we address the relevance, applicability, and use of the DNT study in risk assessment. Conclusions The OECD DNT guideline represents the best available science for assessing the potential for DNT in human health risk assessment, and data generated with this protocol are relevant and reliable for the assessment of these end points. The test methods used have been subjected to an extensive history of international validation, peer review, and evaluation, which is contained in the public record. The reproducibility, reliability, and sensitivity of these methods have been demonstrated, using a wide variety of test substances, in accordance with OECD guidance on the validation and international acceptance of new or updated test methods for hazard characterization. Multiple independent, expert scientific peer reviews affirm these conclusions. PMID:19165382

Highly Reusable Space Transportation (HRST) Baseline Concepts and Analysis: Rocket/RBCC Options. Part 2; A Comparative Study

NASA Technical Reports Server (NTRS)

Woodcock, Gordon

1997-01-01

This study is an extension of a previous effort by the Principal Investigator to develop baseline data to support comparative analysis of Highly Reusable Space Transportation (HRST) concepts. The analyses presented herin develop baseline data bases for two two-stage-to-orbit (TSTO) concepts: (1) Assisted horizontal take-off all rocket (assisted HTOHL); and (2) Assisted vertical take-off rocket based combined cycle (RBCC). The study objectives were to: (1) Provide configuration definitions and illustrations for assisted HTOHL and assisted RBCC; (2) Develop a rationalization approach and compare these concepts with the HRST reference; and (3) Analyze TSTO configurations which try to maintain SSTO benefits while reducing inert weight sensitivity.

Hamstring and Quadriceps Isokinetic Strength Deficits Are Weak Risk Factors for Hamstring Strain Injuries: A 4-Year Cohort Study.

PubMed

van Dyk, Nicol; Bahr, Roald; Whiteley, Rodney; Tol, Johannes L; Kumar, Bhavesh D; Hamilton, Bruce; Farooq, Abdulaziz; Witvrouw, Erik

2016-07-01

A hamstring strain injury (HSI) has become the most common noncontact injury in soccer. Isokinetic muscle strength deficits are considered a risk factor for HSIs. However, underpowered studies with small sample sizes unable to determine small associations have led to inconclusive results regarding the role of isokinetic strength and strength testing in HSIs. To examine whether differences in isokinetic strength measures of knee flexion and extension represent risk factors for hamstring injuries in a large cohort of professional soccer players in an adequately powered study design. Cohort study; Level of evidence, 2. A total of 614 professional soccer players from 14 teams underwent isokinetic strength testing during preseason screening. Testing consisted of concentric knee flexion and extension at 60 deg/s and 300 deg/s and eccentric knee extension at 60 deg/s. A clustered multiple logistic regression analysis was used to identify variables associated with the risk of HSIs. Receiver operating characteristic (ROC) curves were calculated to determine sensitivity and specificity. Of the 614 players, 190 suffered an HSI during the 4 seasons. Quadriceps concentric strength at 60 deg/s (odds ratio [OR], 1.41; 95% CI, 1.03-1.92; P = .03) and hamstring eccentric strength at 60 deg/s (OR, 1.37; 95% CI, 1.01-1.85; P = .04) adjusted for bodyweight were independently associated with the risk of injuries. The absolute differences between the injured and uninjured players were 6.9 N·m and 9.1 N·m, with small effect sizes (d < 0.2). The ROC analyses showed an area under the curve of 0.54 and 0.56 for quadriceps concentric strength and hamstring eccentric strength, respectively, indicating a failed combined sensitivity and specificity of the 2 strength variables identified in the logistic regression models. This study identified small absolute strength differences and a wide overlap of the absolute strength measurements at the group level. The small associations between lower hamstring eccentric strength and lower quadriceps concentric strength with HSIs can only be considered as weak risk factors. The identification of these risk factors still does not allow the identification of individual players at risk. The use of isokinetic testing to determine the association between strength differences and HSIs is not supported. © 2016 The Author(s).

BEATBOX v1.0: Background Error Analysis Testbed with Box Models

NASA Astrophysics Data System (ADS)

Knote, Christoph; Barré, Jérôme; Eckl, Max

2018-02-01

The Background Error Analysis Testbed (BEATBOX) is a new data assimilation framework for box models. Based on the BOX Model eXtension (BOXMOX) to the Kinetic Pre-Processor (KPP), this framework allows users to conduct performance evaluations of data assimilation experiments, sensitivity analyses, and detailed chemical scheme diagnostics from an observation simulation system experiment (OSSE) point of view. The BEATBOX framework incorporates an observation simulator and a data assimilation system with the possibility of choosing ensemble, adjoint, or combined sensitivities. A user-friendly, Python-based interface allows for the tuning of many parameters for atmospheric chemistry and data assimilation research as well as for educational purposes, for example observation error, model covariances, ensemble size, perturbation distribution in the initial conditions, and so on. In this work, the testbed is described and two case studies are presented to illustrate the design of a typical OSSE experiment, data assimilation experiments, a sensitivity analysis, and a method for diagnosing model errors. BEATBOX is released as an open source tool for the atmospheric chemistry and data assimilation communities.

On ultraviolet freeze-in dark matter during reheating

NASA Astrophysics Data System (ADS)

Chen, Shao-Long; Kang, Zhaofeng

2018-05-01

The absence of any confirmative signals from extensive DM searching motivates us to go beyond the conventional WIMPs scenario. The feebly interacting massive particles (FIMPs) paradigm provides a good alternative which, despite of its feebly interaction with the thermal particles, still could correctly produce relic abundance without conventional DM signals. The Infrared-FIMP based on the renormalizable operators is usually suffering the very tiny coupling drawback, which can be overcome in the UltraViolet-FIMP scenario based on high dimensional effective operators. However, it is sensitive to the history of the very early Universe. The previous works terminates this sensitivity at the reheating temperature TRH. We, motivated by its UV-sensitivity, investigate the effects from the even earlier Universe, reheating era. We find that in the usual case with TRHgg mDM, the production rate during reheating is very small as long as the effective operators dimension d <= 8. Besides, we consider the contribution from the mediator, which may be produced during reheating. Moreover, we study the situation when TRH is even lower than mDM and DM can be directly produced during reheating if its mass does not exceed TMAX.

Do Some Students Need Special Protection From Research on Sex and Trauma? New Evidence for Young Adult Resilience in "Sensitive Topics" Research.

PubMed

Rinehart, Jenny K; Nason, Erica E; Yeater, Elizabeth A; Miller, Geoffrey F

2017-01-01

Institutional review boards (IRBs) have expressed concerns that certain individuals or groups, such as participants who are younger, ethnic minorities, or who have certain psychological or personality traits, may be particularly distressed when participating in "sensitive topics" research. This study examined the effects of several demographic and individual difference factors (i.e., age, sex, ethnicity, religiosity, Big Five personality traits, and baseline psychological distress levels) on reactions to participation in sensitive topics research. Participants were 504 undergraduates who completed an extensive battery of either trauma/sex questionnaires or cognitive tests and rated their positive and negative emotional reactions and the perceived benefits and mental costs of participating. They also compared research participation to normal life stressors. Our findings indicated that individual difference and demographic risk factors do not increase participant distress after participating in sex/trauma research over and above that experienced after participating in traditionally minimal-risk cognitive tasks. Participants generally found research participation less distressing than normal life stressors and even enjoyable.

Sensitivity of biomechanical outcomes to independent variations of hindfoot and forefoot stiffness in foot prostheses.

PubMed

Adamczyk, Peter Gabriel; Roland, Michelle; Hahn, Michael E

2017-08-01

Many studies have reported the effects of different foot prostheses on gait, but most results cannot be generalized because the prostheses' properties are seldom reported. We varied hindfoot and forefoot stiffness in an experimental foot prosthesis, in increments of 15N/mm, and tested the parametric effects of these variations on treadmill walking in unilateral transtibial amputees, at speeds from 0.7 to 1.5m/s. We computed outcomes such as prosthesis energy return, center of mass (COM) mechanics, ground reaction forces, and joint mechanics, and computed their sensitivity to component stiffness. A stiffer hindfoot led to reduced prosthesis energy return, increased ground reaction force (GRF) loading rate, and greater stance-phase knee flexion and knee extensor moment. A stiffer forefoot resulted in reduced prosthetic-side ankle push-off and COM push-off work, and increased knee extension and knee flexor moment in late stance. The sensitivity parameters obtained from these tests may be useful in clinical prescription and further research into compensatory mechanisms of joint function. Copyright © 2017 Elsevier B.V. All rights reserved.

MRI helps depict clinically undetectable risk factors in advanced stage retinoblastomas.

PubMed

Galluzzi, Paolo; Hadjistilianou, Theodora; Cerase, Alfonso; Toti, Paolo; Leonini, Sara; Bracco, Sandra; de Francesco, Sonia; Galimberti, Daniela; Balducci, Donatella; Piu, Pietro; Monti, Lucia; Bellini, Matteo; Caini, Mauro; Rossi, Alessandro

2015-02-01

This study compared high-resolution MRI with histology in advanced stage retinoblastomas in which ophthalmoscopy and ultrasonography did not give an exhaustive depiction of the tumour and/or its extension. MRI of orbits and head in 28 retinoblastoma patients (28 eyes) treated with primary enucleation were evaluated. Iris neoangiogenesis, infiltrations of optic nerve, choroid, anterior segment and sclera suspected at MR and histology were compared. Abnormal anterior segment enhancement (AASE) was also correlated with histologically proven infiltrations. Brain images were also evaluated. Significant values were obtained for: prelaminar optic nerve (ON) sensitivity (0.88), positive predictive value (PPV) (0.75) and negative predictive value (NPV) (0.71); post-laminar ON sensitivity (0.50), specificity (0.83), PPV (0.50) and NPV (0.83); overall choroid sensitivity (0.82), and massive choroid NPV (0.69); scleral specificity (1), and NPV (1). AASE correlated with iris neoangiogenesis in 14 out of 19 eyes, and showed significant values for: overall ON PPV (0.65), prelaminar ON sensitivity (0.65), and PPV (0.61), post-laminar ON NPV (0.64); overall choroid sensitivity (0.77), PPV (0.59) and NPV (0.73); scleral NPV (0.83); anterior segment sensitivity (1), and NPV (1). Odds ratios (OR) and accuracy were significant in scleral and prelaminar optic nerve infiltration. Brain examination was unremarkable in all cases. High-resolution MRI may add important findings to clinical evaluation of advanced stage retinoblastomas. © The Author(s) 2015 Reprints and permissions:]br]sagepub.co.uk/journalsPermissions.nav.

Variogram Analysis of Response surfaces (VARS): A New Framework for Global Sensitivity Analysis of Earth and Environmental Systems Models

NASA Astrophysics Data System (ADS)

Razavi, S.; Gupta, H. V.

2015-12-01

Earth and environmental systems models (EESMs) are continually growing in complexity and dimensionality with continuous advances in understanding and computing power. Complexity and dimensionality are manifested by introducing many different factors in EESMs (i.e., model parameters, forcings, boundary conditions, etc.) to be identified. Sensitivity Analysis (SA) provides an essential means for characterizing the role and importance of such factors in producing the model responses. However, conventional approaches to SA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we present a new and general sensitivity analysis framework (called VARS), based on an analogy to 'variogram analysis', that provides an intuitive and comprehensive characterization of sensitivity across the full spectrum of scales in the factor space. We prove, theoretically, that Morris (derivative-based) and Sobol (variance-based) methods and their extensions are limiting cases of VARS, and that their SA indices can be computed as by-products of the VARS framework. We also present a practical strategy for the application of VARS to real-world problems, called STAR-VARS, including a new sampling strategy, called "star-based sampling". Our results across several case studies show the STAR-VARS approach to provide reliable and stable assessments of "global" sensitivity across the full range of scales in the factor space, while being at least 1-2 orders of magnitude more efficient than the benchmark Morris and Sobol approaches.

A review of mechanistic insight and application of pH-sensitive liposomes in drug delivery.

PubMed

Paliwal, Shivani Rai; Paliwal, Rishi; Vyas, Suresh P

2015-05-01

The pH-sensitive liposomes have been extensively used as an alternative to conventional liposomes in effective intracellular delivery of therapeutics/antigen/DNA/diagnostics to various compartments of the target cell. Such liposomes are destabilized under acidic conditions of the endocytotic pathway as they usually contain pH-sensitive lipid components. Therefore, the encapsulated content is delivered into the intracellular bio-environment through destabilization or its fusion with the endosomal membrane. The therapeutic efficacy of pH-sensitive liposomes enables them as biomaterial with commercial utility especially in cancer treatment. In addition, targeting ligands including antibodies can be anchored on the surface of pH-sensitive liposomes to target specific cell surface receptors/antigen present on tumor cells. These vesicles have also been widely explored for antigen delivery and serve as immunological adjuvant to enhance the immune response to antigens. The present review deals with recent research updates on application of pH-sensitive liposomes in chemotherapy/diagnostics/antigen/gene delivery etc.

Improvements to the YbF electron electric dipole moment experiment

NASA Astrophysics Data System (ADS)

Sauer, B. E.; Rabey, I. M.; Devlin, J. A.; Tarbutt, M. R.; Ho, C. J.; Hinds, E. A.

2017-04-01

The standard model of particle physics predicts that the permanent electric dipole moment (EDM) of the electron is very nearly zero. Many extensions to the standard model predict an electron EDM just below current experimental limits. We are currently working to improve the sensitivity of the Imperial College YbF experiment. We have implemented combined laser-radiofrequency pumping techniques which both increase the number of molecules which participate in the EDM experiment and also increase the probability of detection. Combined, these techniques give nearly two orders of magnitude increase in the experimental sensitivity. At this enhanced sensitivity magnetic effects which were negligible become important. We have developed a new way to construct the electrodes for electric field plates which minimizes the effect of magnetic Johnson noise. The new YbF experiment is expected to comparable in sensitivity to the most sensitive measurements of the electron EDM to date. We will also discuss laser cooling techniques which promise an even larger increase in sensitivity.

Comparison of patterns of allergen sensitization among inner-city Hispanic and African American children with asthma.

PubMed

Rastogi, Deepa; Reddy, Mamta; Neugebauer, Richard

2006-11-01

Among Hispanics, the largest minority ethnic group in the United States, asthma prevalence is increasing, particularly in inner-city neighborhoods. Although allergen sensitization among asthmatic African Americans has been extensively studied, similar details are not available for Hispanic children. To examine patterns of allergen sensitization, including the association with illness severity, in asthmatic children overall and in Hispanic and African American children living in a socioeconomically disadvantaged area of New York City. A retrospective medical record review of asthmatic children attending a community hospital in the South Bronx area of New York City was performed. Information abstracted included demographics, asthma severity classification, reported exposures to indoor allergens, and results of allergy testing. Among 384 children in the analysis, 270 (70.3%) were Hispanic and 114 (29.7%) were African American. Sensitization to indoor and outdoor allergens, respectively, did not differ between Hispanic (58.5% and 27.0%) and African American (58.8% and 32.6%) children. Allergen sensitization exhibited a direct, significant association with asthma severity for indoor allergens for the 2 ethnic groups combined and for Hispanics separately but not between asthma severity and outdoor allergens (P < .01). No correlation was found between self-reported allergen exposure and sensitization. Patterns of allergen sensitization among inner-city Hispanic asthmatic children resemble those among African American children, a finding that is likely explained by the similarity in levels of environmental exposures. With the increasing prevalence of asthma among inner-city Hispanic children, skin testing should be used frequently for objective evaluation of asthma in this ethnic group.

Ecotoxicity of boric acid in standard laboratory tests with plants and soil organisms.

PubMed

Princz, Juliska; Becker, Leonie; Scheffczyk, Adam; Stephenson, Gladys; Scroggins, Rick; Moser, Thomas; Römbke, Jörg

2017-05-01

To verify the continuous sensitivity of ecotoxicological tests (mainly the test organisms), reference substances with known toxicity are regularly tested. Ideally, this substance(s) would lack specificity in its mode action, be bioavailable and readily attainable with cost-effective means of chemical characterization. Boric acid has satisfied these criteria, but has most recently been characterized as a substance of very high concern, due to reproductive effects in humans, thus limiting its recommendation as an ideal reference toxicant. However, there is probably no other chemical for which ecotoxicity in soil has been so intensively studied; an extensive literature review yielded lethal (including avoidance) and sublethal data for 38 taxa. The ecotoxicity data were evaluated using species sensitivity distributions, collectively across all taxa, and separately according to species type, endpoints, soil type and duration. The lack of specificity in the mode of action yielded broad toxicity among soil taxa and soil types, and provided a collective approach to assessing species sensitivity, while taking into consideration differences in test methodologies and exposure durations. Toxicity was species-specific with Folsomia candida and enchytraied species demonstrating the most sensitivity; among plants, the following trend occurred: dicotyledonous (more sensitive) ≫ monocotyledonous ≫ gymnosperm species. Sensitivity was also time and endpoint specific, with endpoints such as lethality and avoidance being less sensitive than reproduction effects. Furthermore, given the breadth of data and toxicity demonstrated by boric acid, lessons learned from its evaluation are discussed to recommend the properties required by an ideal reference substance for the soil compartment.

High blood pressure and visual sensitivity

NASA Astrophysics Data System (ADS)

Eisner, Alvin; Samples, John R.

2003-09-01

The study had two main purposes: (1) to determine whether the foveal visual sensitivities of people treated for high blood pressure (vascular hypertension) differ from the sensitivities of people who have not been diagnosed with high blood pressure and (2) to understand how visual adaptation is related to standard measures of systemic cardiovascular function. Two groups of middle-aged subjects-hypertensive and normotensive-were examined with a series of test/background stimulus combinations. All subjects met rigorous inclusion criteria for excellent ocular health. Although the visual sensitivities of the two subject groups overlapped extensively, the age-related rate of sensitivity loss was, for some measures, greater for the hypertensive subjects, possibly because of adaptation differences between the two groups. Overall, the degree of steady-state sensitivity loss resulting from an increase of background illuminance (for 580-nm backgrounds) was slightly less for the hypertensive subjects. Among normotensive subjects, the ability of a bright (3.8-log-td), long-wavelength (640-nm) adapting background to selectively suppress the flicker response of long-wavelength-sensitive (LWS) cones was related inversely to the ratio of mean arterial blood pressure to heart rate. The degree of selective suppression was also related to heart rate alone, and there was evidence that short-term changes of cardiovascular response were important. The results suggest that (1) vascular hypertension, or possibly its treatment, subtly affects visual function even in the absence of eye disease and (2) changes in blood flow affect retinal light-adaptation processes involved in the selective suppression of the flicker response from LWS cones caused by bright, long-wavelength backgrounds.

PRNP variants in goats reduce sensitivity of detection of PrPSc by immunoassay

USDA-ARS?s Scientific Manuscript database

Immunoassays are extensively utilized in disease diagnostics with monoclonal antibodies serving as critical tools within the assay. Detection of scrapie in sheep and goats relies heavily on immunoassays including immunohistochemistry, western blotting, and ELISA. In the United States, regulatory tes...

Exercise training reverses the negative effects of chronic L-arginine supplementation on insulin sensitivity.

PubMed

Salgueiro, Rafael Barrera; Gerlinger-Romero, Frederico; Guimarães-Ferreira, Lucas; de Castro Barbosa, Thais; Nunes, Maria Tereza

2017-12-15

L-Arginine has emerged as an important supplement for athletes and non-athletes in order to improve performance. Arginine has been extensively used as substrate for nitric oxide synthesis, leading to increased vasodilatation and hormonal secretion. However, the chronic consumption of arginine has been shown to impair insulin sensitivity. In the present study, we aimed to evaluate whether chronic arginine supplementation associated with exercise training would have a beneficial impact on insulin sensitivity. We, therefore, treated Wistar rats for 4weeks with arginine, associated or not with exercise training (treadmill). We assessed the somatotropic activation, by evaluating growth hormone (GH) gene expression and protein content in the pituitary, as well is GH concentration in the serum. Additionally, we evaluate whole-body insulin sensitivity, by performing an insulin tolerance test. Skeletal muscle morpho-physiological parameters were also assessed. Insulin sensitivity was impaired in the arginine-treated rats. However, exercise training reversed the negative effects of arginine. Arginine and exercise training increased somatotropic axis function, muscle mass and body weight gain. The combination arginine and exercise training further decreased total fat mass. Our results confirm that chronic arginine supplementation leads to insulin resistance, which can be reversed in the association with exercise training. We provide further evidence that exercise training is an important tool to improve whole-body metabolism. Copyright © 2017 Elsevier Inc. All rights reserved.

Optical Coherence Tomography Angiography versus Dye Angiography in Age-Related Macular Degeneration: Sensitivity and Specificity Analysis.

PubMed

Nikolopoulou, Eleni; Lorusso, Massimo; Micelli Ferrari, Luisa; Cicinelli, Maria Vittoria; Bandello, Francesco; Querques, Giuseppe; Micelli Ferrari, Tommaso

2018-01-01

Optical coherence tomography angiography (OCTA) could be a valid tool to detect choroidal neovascularization (CNV) in neovascular age-related macular degeneration (nAMD), allowing the analysis of the type, the morphology, and the extension of CNV in most of the cases. To determine the sensitivity and specificity of OCTA in detecting CNV secondary to nAMD, compared to fluorescein angiography (FA) and indocyanine green angiography (ICGA). Prospective observational study. Patients with suspected nAMD were recruited between May and December 2016. Patients underwent FA, ICGA, spectral domain OCT, and OCTA (AngioVue, Optovue, Inc.). Sensitivity and specificity of FA, with or without ICGA, were assessed and compared with OCTA. Seventy eyes of 70 consecutive patients were included: 32 eyes (45.7%) with type I CNV, 8 eyes (11.4%) with type II CNV, 4 eyes (5.7%) with type III CNV, 6 eyes (8.6%) with mixed type I and type II CNV, and 20 eyes (28.6%) with no CNV. Sensitivity of OCTA was 88% and specificity was 90%. Concordance between FA/ICGA and OCTA was very good (0,91; range 0,81-1,00). OCTA showed high sensitivity and specificity for detection of CNV. Concordance between OCTA and gold-standard dye-based techniques was excellent. OCTA may represent a first-line noninvasive method for the diagnosis of nAMD.

Hybrid generative-discriminative approach to age-invariant face recognition

NASA Astrophysics Data System (ADS)

Sajid, Muhammad; Shafique, Tamoor

2018-03-01

Age-invariant face recognition is still a challenging research problem due to the complex aging process involving types of facial tissues, skin, fat, muscles, and bones. Most of the related studies that have addressed the aging problem are focused on generative representation (aging simulation) or discriminative representation (feature-based approaches). Designing an appropriate hybrid approach taking into account both the generative and discriminative representations for age-invariant face recognition remains an open problem. We perform a hybrid matching to achieve robustness to aging variations. This approach automatically segments the eyes, nose-bridge, and mouth regions, which are relatively less sensitive to aging variations compared with the rest of the facial regions that are age-sensitive. The aging variations of age-sensitive facial parts are compensated using a demographic-aware generative model based on a bridged denoising autoencoder. The age-insensitive facial parts are represented by pixel average vector-based local binary patterns. Deep convolutional neural networks are used to extract relative features of age-sensitive and age-insensitive facial parts. Finally, the feature vectors of age-sensitive and age-insensitive facial parts are fused to achieve the recognition results. Extensive experimental results on morphological face database II (MORPH II), face and gesture recognition network (FG-NET), and Verification Subset of cross-age celebrity dataset (CACD-VS) demonstrate the effectiveness of the proposed method for age-invariant face recognition well.

Pharmacological extension of the sensitive period for imprinting in Gallus domesticus.

PubMed

Parsons, C H; Rogers, L J

1997-12-01

Precocial animals, such as the chick, exhibit a form of learning termed filial imprinting. The chick's sensitive period for filial imprinting is restricted to the first few days after hatching. The neural mechanism that terminates the sensitive period is not fully understood. It is thought to be an experience-dependent event because once a chick has imprinted, it will not readily imprint on another stimulus. However, even dark-reared chicks eventually lose the ability to imprint, which suggests that the ending of the sensitive period may not be entirely experience-dependent. The present study investigates factors that may contribute to the ending of the sensitive period. In our experiments, dark-reared chicks were unable to imprint after Day 2 posthatching, but chicks treated 10 h after hatching with an intramuscular injection of the noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist ketamine (55 mg/kg) and the alpha2-adrenoceptor agonist xylazine (6 mg/kg) (KX) imprinted on a stuffed hen 8 days after hatching. Similarly treated chicks did not imprint on a red and black box, although the box was an effective imprinting stimulus for Day 2 chicks. Chicks treated with KX at 20 or 40 h posthatching or on Day 4 or 7 as well as controls treated with pyrogen-free saline were unable to imprint on Day 8.

The tarsal taste of honey bees: behavioral and electrophysiological analyses

PubMed Central

de Brito Sanchez, Maria Gabriela; Lorenzo, Esther; Su, Songkun; Liu, Fanglin; Zhan, Yi; Giurfa, Martin

2014-01-01

Taste plays a crucial role in the life of honey bees as their survival depends on the collection and intake of nectar and pollen, and other natural products. Here we studied the tarsal taste of honey bees through a series of behavioral and electrophysiological analyses. We characterized responsiveness to various sweet, salty and bitter tastants delivered to gustatory sensilla of the fore tarsi. Behavioral experiments showed that stimulation of opposite fore tarsi with sucrose and bitter substances or water yielded different outcomes depending on the stimulation sequence. When sucrose was applied first, thereby eliciting proboscis extension, no bitter substance could induce proboscis retraction, thus suggesting that the primacy of sucrose stimulation induced a central excitatory state. When bitter substances or water were applied first, sucrose stimulation could still elicit proboscis extension but to a lower level, thus suggesting central inhibition based on contradictory gustatory input on opposite tarsi. Electrophysiological experiments showed that receptor cells in the gustatory sensilla of the tarsomeres are highly sensitive to saline solutions at low concentrations. No evidence for receptors responding specifically to sucrose or to bitter substances was found in these sensilla. Receptor cells in the gustatory sensilla of the claws are highly sensitive to sucrose. Although bees do not possess dedicated bitter-taste receptors in the tarsi, indirect bitter detection is possible because bitter tastes inhibit sucrose receptor cells of the claws when mixed with sucrose solution. By combining behavioral and electrophysiological approaches, these results provide the first integrative study on tarsal taste detection in the honey bee. PMID:24550801

The tarsal taste of honey bees: behavioral and electrophysiological analyses.

PubMed

de Brito Sanchez, Maria Gabriela; Lorenzo, Esther; Su, Songkun; Liu, Fanglin; Zhan, Yi; Giurfa, Martin

2014-01-01

Taste plays a crucial role in the life of honey bees as their survival depends on the collection and intake of nectar and pollen, and other natural products. Here we studied the tarsal taste of honey bees through a series of behavioral and electrophysiological analyses. We characterized responsiveness to various sweet, salty and bitter tastants delivered to gustatory sensilla of the fore tarsi. Behavioral experiments showed that stimulation of opposite fore tarsi with sucrose and bitter substances or water yielded different outcomes depending on the stimulation sequence. When sucrose was applied first, thereby eliciting proboscis extension, no bitter substance could induce proboscis retraction, thus suggesting that the primacy of sucrose stimulation induced a central excitatory state. When bitter substances or water were applied first, sucrose stimulation could still elicit proboscis extension but to a lower level, thus suggesting central inhibition based on contradictory gustatory input on opposite tarsi. Electrophysiological experiments showed that receptor cells in the gustatory sensilla of the tarsomeres are highly sensitive to saline solutions at low concentrations. No evidence for receptors responding specifically to sucrose or to bitter substances was found in these sensilla. Receptor cells in the gustatory sensilla of the claws are highly sensitive to sucrose. Although bees do not possess dedicated bitter-taste receptors in the tarsi, indirect bitter detection is possible because bitter tastes inhibit sucrose receptor cells of the claws when mixed with sucrose solution. By combining behavioral and electrophysiological approaches, these results provide the first integrative study on tarsal taste detection in the honey bee.

Characterizing the Sensitivity of Groundwater Storage to Climate variation in the Indus Basin

NASA Astrophysics Data System (ADS)

Huang, L.; Sabo, J. L.

2017-12-01

Indus Basin represents an extensive groundwater aquifer facing the challenge of effective management of limited water resources. Groundwater storage is one of the most important variables of water balance, yet its sensitivity to climate change has rarely been explored. To better estimate present and future groundwater storage and its sensitivity to climate change in the Indus Basin, we analyzed groundwater recharge/discharge and their historical evolution in this basin. Several methods are applied to specify the aquifer system including: water level change and storativity estimates, gravity estimates (GRACE), flow model (MODFLOW), water budget analysis and extrapolation. In addition, all of the socioeconomic and engineering aspects are represented in the hydrological system through the change of temporal and spatial distributions of recharge and discharge (e.g., land use, crop structure, water allocation, etc.). Our results demonstrate that the direct impacts of climate change will result in unevenly distributed but increasing groundwater storage in the short term through groundwater recharge. In contrast, long term groundwater storage will decrease as a result of combined indirect and direct impacts of climate change (e.g. recharge/discharge and human activities). The sensitivity of groundwater storage to climate variation is characterized by topography, aquifer specifics and land use. Furthermore, by comparing possible outcomes of different human interventions scenarios, our study reveals human activities play an important role in affecting the sensitivity of groundwater storage to climate variation. Over all, this study presents the feasibility and value of using integrated hydrological methods to support sustainable water resource management under climate change.

Statistical power and utility of meta-analysis methods for cross-phenotype genome-wide association studies.

PubMed

Zhu, Zhaozhong; Anttila, Verneri; Smoller, Jordan W; Lee, Phil H

2018-01-01

Advances in recent genome wide association studies (GWAS) suggest that pleiotropic effects on human complex traits are widespread. A number of classic and recent meta-analysis methods have been used to identify genetic loci with pleiotropic effects, but the overall performance of these methods is not well understood. In this work, we use extensive simulations and case studies of GWAS datasets to investigate the power and type-I error rates of ten meta-analysis methods. We specifically focus on three conditions commonly encountered in the studies of multiple traits: (1) extensive heterogeneity of genetic effects; (2) characterization of trait-specific association; and (3) inflated correlation of GWAS due to overlapping samples. Although the statistical power is highly variable under distinct study conditions, we found the superior power of several methods under diverse heterogeneity. In particular, classic fixed-effects model showed surprisingly good performance when a variant is associated with more than a half of study traits. As the number of traits with null effects increases, ASSET performed the best along with competitive specificity and sensitivity. With opposite directional effects, CPASSOC featured the first-rate power. However, caution is advised when using CPASSOC for studying genetically correlated traits with overlapping samples. We conclude with a discussion of unresolved issues and directions for future research.

Diagnostic performance of semi-quantitative and quantitative stress CMR perfusion analysis: a meta-analysis.

PubMed

van Dijk, R; van Assen, M; Vliegenthart, R; de Bock, G H; van der Harst, P; Oudkerk, M

2017-11-27

Stress cardiovascular magnetic resonance (CMR) perfusion imaging is a promising modality for the evaluation of coronary artery disease (CAD) due to high spatial resolution and absence of radiation. Semi-quantitative and quantitative analysis of CMR perfusion are based on signal-intensity curves produced during the first-pass of gadolinium contrast. Multiple semi-quantitative and quantitative parameters have been introduced. Diagnostic performance of these parameters varies extensively among studies and standardized protocols are lacking. This study aims to determine the diagnostic accuracy of semi- quantitative and quantitative CMR perfusion parameters, compared to multiple reference standards. Pubmed, WebOfScience, and Embase were systematically searched using predefined criteria (3272 articles). A check for duplicates was performed (1967 articles). Eligibility and relevance of the articles was determined by two reviewers using pre-defined criteria. The primary data extraction was performed independently by two researchers with the use of a predefined template. Differences in extracted data were resolved by discussion between the two researchers. The quality of the included studies was assessed using the 'Quality Assessment of Diagnostic Accuracy Studies Tool' (QUADAS-2). True positives, false positives, true negatives, and false negatives were subtracted/calculated from the articles. The principal summary measures used to assess diagnostic accuracy were sensitivity, specificity, andarea under the receiver operating curve (AUC). Data was pooled according to analysis territory, reference standard and perfusion parameter. Twenty-two articles were eligible based on the predefined study eligibility criteria. The pooled diagnostic accuracy for segment-, territory- and patient-based analyses showed good diagnostic performance with sensitivity of 0.88, 0.82, and 0.83, specificity of 0.72, 0.83, and 0.76 and AUC of 0.90, 0.84, and 0.87, respectively. In per territory analysis our results show similar diagnostic accuracy comparing anatomical (AUC 0.86(0.83-0.89)) and functional reference standards (AUC 0.88(0.84-0.90)). Only the per territory analysis sensitivity did not show significant heterogeneity. None of the groups showed signs of publication bias. The clinical value of semi-quantitative and quantitative CMR perfusion analysis remains uncertain due to extensive inter-study heterogeneity and large differences in CMR perfusion acquisition protocols, reference standards, and methods of assessment of myocardial perfusion parameters. For wide spread implementation, standardization of CMR perfusion techniques is essential. CRD42016040176 .

Highly sensitive C-reactive protein (CRP) assay using metal-enhanced fluorescence (MEF)

NASA Astrophysics Data System (ADS)

Zhang, Yi; Keegan, Gemma L.; Stranik, Ondrej; Brennan-Fournet, Margaret E.; McDonagh, Colette

2015-07-01

Fluorescence has been extensively employed in the area of diagnostic immunoassays. A significant enhancement of fluorescence can be achieved when noble metal nanoparticles are placed in close proximity to fluorophores. This effect, referred to as metal-enhanced fluorescence (MEF), has the potential to produce immunoassays with a high sensitivity and a low limit of detection (LOD). In this study, we investigate the fluorescence enhancement effect of two different nanoparticle systems, large spherical silver nanoparticles (AgNPs) and gold edge-coated triangular silver nanoplates, and both systems were evaluated for MEF. The extinction properties and electric field enhancement of both systems were modeled, and the optimum system, spherical AgNPs, was used in a sandwich immunoassay for human C-reactive protein with a red fluorescent dye label. A significant enhancement in the fluorescence was observed, which corresponded to an LOD improvement of 19-fold compared to a control assay without AgNPs.

Synthesis and characterization of UV-treated Fe-doped bismuth lanthanum titanate-doped TiO2 layers in dye-sensitized solar cells

NASA Astrophysics Data System (ADS)

Song, Myoung Geun; Bark, Chung Wung

2016-06-01

Dye-sensitized solar cells (DSSCs) based on titanium dioxide (TiO2) have been extensively studied because they constitute promising low-cost alternatives to their conventional semiconductor-based counterparts. However, much of the effort aimed at achieving high conversion efficiencies has focused on dye and liquid electrolytes. In this work, we report the photovoltaic characteristics of DSSCs fabricated by mixing TiO2 with Fe-doped bismuth lanthanum titanate (Fe-BLT). These nanosized Fe-BLT powders were prepared by using a high-energy ball-milling process. In addition, we used a UV radiation-ozone (UV-O3) treatment to change the surface wettability of TiO2 from hydrophobic to hydrophilic and thereby prevented the easy separation of the Fe-BLT-mixed TiO2 from the fluorine-doped tin-oxide (FTO) coating glass.

Ovary activation does not correlate with pollen and nectar foraging specialization in the bumblebee Bombus impatiens.

PubMed

Simons, Meagan A; Smith, Adam R

2018-01-01

Social insect foragers may specialize on certain resource types. Specialization on pollen or nectar among honeybee foragers is hypothesized to result from associations between reproductive physiology and sensory tuning that evolved in ancestral solitary bees (the Reproductive Ground-Plan Hypothesis; RGPH). However, the two non-honeybee species studied showed no association between specialization and ovary activation. Here we investigate the bumblebee B. impatiens because it has the most extensively studied pollen/nectar specialization of any bumblebee. We show that ovary size does not differ between pollen specialist, nectar specialist, and generalist foragers, contrary to the predictions of the RGPH. However, we also found mixed support for the second prediction of the RGPH, that sensory sensitivity, measured through proboscis extension response (PER), is greater among pollen foragers. We also found a correlation between foraging activity and ovary size, and foraging activity and relative nectar preference, but no correlation between ovary size and nectar preference. In one colony non-foragers had larger ovaries than foragers, supporting the reproductive conflict and work hypothesis, but in the other colony they did not.

Ovary activation does not correlate with pollen and nectar foraging specialization in the bumblebee Bombus impatiens

PubMed Central

Simons, Meagan A.

2018-01-01

Social insect foragers may specialize on certain resource types. Specialization on pollen or nectar among honeybee foragers is hypothesized to result from associations between reproductive physiology and sensory tuning that evolved in ancestral solitary bees (the Reproductive Ground-Plan Hypothesis; RGPH). However, the two non-honeybee species studied showed no association between specialization and ovary activation. Here we investigate the bumblebee B. impatiens because it has the most extensively studied pollen/nectar specialization of any bumblebee. We show that ovary size does not differ between pollen specialist, nectar specialist, and generalist foragers, contrary to the predictions of the RGPH. However, we also found mixed support for the second prediction of the RGPH, that sensory sensitivity, measured through proboscis extension response (PER), is greater among pollen foragers. We also found a correlation between foraging activity and ovary size, and foraging activity and relative nectar preference, but no correlation between ovary size and nectar preference. In one colony non-foragers had larger ovaries than foragers, supporting the reproductive conflict and work hypothesis, but in the other colony they did not. PMID:29479503

Exposure of Mn and FeSODs, but not Cu/ZnSOD, to NO leads to nitrosonium and nitroxyl ions generation which cause enzyme modification and inactivation: an in vitro study.

PubMed

Niketíc, V; Stojanović, S; Nikolić, A; Spasić, M; Michelson, A M

1999-11-01

The effect of NO treatment in vitro on structural and functional alterations of Cu/Zn, Mn, and Fe type of SODs was studied. Significant difference in response to NO of Cu/ZnSOD compared to the Mn and Fe types was demonstrated. Cu/ZnSOD was shown to be stable with respect to NO: even on prolonged exposure, NO produced negligible effect on its structure and activity. In contrast, both Mn and Fe types were found to be NO-sensitive: exposure to NO led to their fast and extensive inactivation, which was accompanied by extensive structural alterations, including (in some of the samples tested) the cleavage of enzyme polypeptide chains, presumably at His residues of the enzyme metal binding sites. The generation of nitrosonium (NO+) and nitroxyl (NO-) ions in NO treated Mn and FeSODs, which produce enzyme modifications and inactivation, was demonstrated. The physiological and biomedical significance of described findings is briefly discussed.

The KASCADE-Grande experiment

NASA Astrophysics Data System (ADS)

Apel, W. D.; Arteaga, J. C.; Badea, A. F.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Link, K.; łuczak, P.; Ludwig, M.; Mathes, H. J.; Mayer, H. J.; Melissas, M.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.

2010-08-01

KASCADE-Grande is the enlargement of the KASCADE extensive air shower detector, realized to expand the cosmic ray studies from the previous 10 14-10 17 eV primary energy range to 10 18 eV. This is performed by extending the area covered by the KASCADE electromagnetic array from 200×200 to 700×700 m 2 by means of 37 scintillator detector stations of 10 m 2 area each. This new array is named Grande and provides measurements of the all-charged particle component of extensive air showers ( Nch), while the original KASCADE array particularly provides information on the muon content (Nμ). Additional dense compact detector set-ups being sensitive to energetic hadrons and muons are used for data consistency checks and calibration purposes. The performance of the Grande array and its integration into the entire experimental complex is discussed. It is demonstrated that the overall observable resolutions are adequate to meet the physical requirements of the measurements, i.e. primary energy spectrum and elemental composition studies in the primary cosmic ray energy range of 10 16-10 18 eV.

Hydra, a model system for environmental studies.

PubMed

Quinn, Brian; Gagné, François; Blaise, Christian

2012-01-01

Hydra have been extensively used for studying the teratogenic and toxic potential of numerous toxins throughout the years and are more recently growing in popularity to assess the impacts of environmental pollutants. Hydra are an appropriate bioindicator species for use in environmental assessment owing to their easily measurable physical (morphology), biochemical (xenobiotic biotransformation; oxidative stress), behavioural (feeding) and reproductive (sexual and asexual) endpoints. Hydra also possess an unparalleled ability to regenerate, allowing the assessment of teratogenic compounds and the impact of contaminants on stem cells. Importantly, Hydra are ubiquitous throughout freshwater environments and relatively easy to culture making them appropriate for use in small scale bioassay systems. Hydra have been used to assess the environmental impacts of numerous environmental pollutants including metals, organic toxicants (including pharmaceuticals and endocrine disrupting compounds), nanomaterials and industrial and municipal effluents. They have been found to be among the most sensitive animals tested for metals and certain effluents, comparing favourably with more standardised toxicity tests. Despite their lack of use in formalised monitoring programmes, Hydra have been extensively used and are regarded as a model organism in aquatic toxicology.

Extensively Drug-Resistant Tuberculosis (XDR-TB) - A Potential Threat in Ireland

PubMed Central

Mc Laughlin, Anne Marie; O’Donnell, Rory A; Gibbons, Noel; Scully, Mary; O’Flangan, Darina; Keane, Joseph

2007-01-01

We describe a case of a 25 year old female from Lithuania who presented with a productive cough. Chest radiograph demonstrated an infiltrate in the left upper lobe and a cavitating lesion in the right middle lobe. Sensitivity testing of her sputum led to a diagnosis of extensively drug-resistant tuberculosis (XDR-TB). This is the first case in Ireland and highlights the need for physicians to be aware of the possibility of XDR-TB. Moreover it underlines the need for improvement in service provision in terms of a TB reference laboratory and TB clinics. PMID:19340317

Spatial analysis of extension fracture systems: A process modeling approach

USGS Publications Warehouse

Ferguson, C.C.

1985-01-01

Little consensus exists on how best to analyze natural fracture spacings and their sequences. Field measurements and analyses published in geotechnical literature imply fracture processes radically different from those assumed by theoretical structural geologists. The approach adopted in this paper recognizes that disruption of rock layers by layer-parallel extension results in two spacing distributions, one representing layer-fragment lengths and another separation distances between fragments. These two distributions and their sequences reflect mechanics and history of fracture and separation. Such distributions and sequences, represented by a 2 ?? n matrix of lengthsL, can be analyzed using a method that is history sensitive and which yields also a scalar estimate of bulk extension, e (L). The method is illustrated by a series of Monte Carlo experiments representing a variety of fracture-and-separation processes, each with distinct implications for extension history. Resulting distributions of e (L)are process-specific, suggesting that the inverse problem of deducing fracture-and-separation history from final structure may be tractable. ?? 1985 Plenum Publishing Corporation.

Equity Sensitivity in Illinois Public School Teachers

ERIC Educational Resources Information Center

Grossi, Robert G.

2013-01-01

Research supports the importance of teacher quality on effective student learning. School districts recognize this fact and focus extensively on hiring quality teachers and improving teaching skills through professional development programs. Amazingly, despite common sense and a vast amount of research that reflects that employee performance is a…

The Utility of the Small Rodent Electrocardiogram in Toxicology

EPA Science Inventory

Extensive research has lead to a growing appreciation that the heart is acutely sensitive to a broad array of toxicants via multiple routes of exposure. These agents are as diverse as the anti-neoplastic drug doxorubicin and various components of ambient air pollution. Adverse ef...

Risk Factors for Repetition of Self-Harm: A Systematic Review of Prospective Hospital-Based Studies

PubMed Central

Larkin, Celine; Di Blasi, Zelda; Arensman, Ella

2014-01-01

Background Self-harm entails high costs to individuals and society in terms of suicide risk, morbidity and healthcare expenditure. Repetition of self-harm confers yet higher risk of suicide and risk assessment of self-harm patients forms a key component of the health care management of self-harm patients. To date, there has been no systematic review published which synthesises the extensive evidence on risk factors for repetition. Objective This review is intended to identify risk factors for prospective repetition of self-harm after an index self-harm presentation, irrespective of suicidal intent. Data sources PubMed, PsychInfo and Scirus were used to search for relevant publications. We included cohort studies which examining factors associated with prospective repetition among those presenting with self-harm to emergency departments. Journal articles, abstracts, letters and theses in any language published up to June 2012 were considered. Studies were quality-assessed and synthesised in narrative form. Results A total of 129 studies, including 329,001 participants, met our inclusion criteria. Some factors were studied extensively and were found to have a consistent association with repetition. These included previous self-harm, personality disorder, hopelessness, history of psychiatric treatment, schizophrenia, alcohol abuse/dependence, drug abuse/dependence, and living alone. However, the sensitivity values of these measures varied greatly across studies. Psychological risk factors and protective factors have been relatively under-researched but show emerging associations with repetition. Composite risk scales tended to have high sensitivity but poor specificity. Conclusions Many risk factors for repetition of self-harm match risk factors for initiation of self-harm, but the most consistent evidence for increased risk of repetition comes from long-standing psychosocial vulnerabilities, rather than characteristics of an index episode. The current review will enhance prediction of self-harm and assist in the efficient allocation of intervention resources. PMID:24465400

Neutral point testing of color vision in the domestic cat.

PubMed

Clark, Daria L; Clark, Robert A

2016-12-01

Despite extensive study, the basic nature of feline spectral sensitivity is still unresolved. Most electrophysiological studies have demonstrated two photopic receptors within the cat's retina, one most sensitive to longer wavelengths near 560 nm and the other most sensitive to shorter wavelengths near 460 nm, providing the neuroretinal basis for dichromatic vision. A few studies, however, have detected a third photopic receptor most sensitive to medium wavelengths between 500 and 520 nm, overlapping in spectrally sensitivity with the feline scotopic receptor, that potentially could allow trichromatic vision. Indeed, one behavioral study has demonstrated trichromatic vision in cats, but a flaw within its experimental design raises the possibility that achromatic intensity cues might have allowed the accurate identification of medium wavelength targets. This study tested for a spectral neutral point in the domestic cat using a two-choice discrimination task. The positive targets were created using monochromatic light from various single wavelength light emitting diodes (LEDs) combined with a white light of variable intensity, while the negative targets were created using white light of variable intensity. Trials were performed with varying intensities of positive and negative targets, from brighter positive targets to brighter negative targets, to eliminate achromatic intensity cues. Two cats with prior experience with two-choice discrimination tasks, one male and one female, successfully discriminated monochromatic light from 456 nm to 497 nm and from 510 nm to 524 nm, but both failed to discriminate monochromatic light at 505 nm over multiple trials. These results provide strong evidence that cats are dichromatic with a neutral point near 505 nm. This neutral point is nearly identical to the neutral point of the human deuteuranope, making feline vision a more accurate a model for red-green colorblind individuals than normal trichromats. Copyright © 2016 Elsevier Ltd. All rights reserved.

Whole-cell patch clamp recording of voltage-sensitive Ca²+ channel currents: heterologous expression systems and dissociated brain neurons.

PubMed

Hainsworth, Atticus H; Randall, Andrew D; Stefani, Alessandro

2005-01-01

Voltage-sensitive Ca(2+) channels (VSCC) play a central role in an extensive array of physiological processes. Their importance in cellular function arises from their ability both to sense membrane voltage and to conduct Ca(2+) ions, two facets that couple membrane excitability to a key intracellular second messenger. Through this relationship, activation of VSCCs is tightly coupled to the gamut of cellular functions dependent on intracellular Ca(2+), including muscle contraction, energy metabolism, gene expression, and exocytotic/endocytotic cycling.

Extending lifetimes of lanthanide-based near-infrared emitters (Nd, Yb) in the millisecond range through Cr(III) sensitization in discrete bimetallic edifices.

PubMed

Imbert, Daniel; Cantuel, Martine; Bünzli, Jean-Claude G; Bernardinelli, Gérald; Piguet, Claude

2003-12-24

A [Cr(alpha,alpha'-diimine)3]3+ chromophore is used as a donor for sensitizing NdIII and YbIII near-infrared (NIR) emitters in the heterobimetallic helicates [LnCrIIIL3]6+. The intramolecular CrIII --> LnIII energy transfer process controls the population of the lanthanide-centered emitting levels, thus leading to unprecedented extension of the NIR luminescence decay times in the millisecond range for Nd and Yb ions incorporated in coordination complexes.

Graphene: Nanostructure engineering and applications

NASA Astrophysics Data System (ADS)

Zhang, Tingting; Wu, Shuang; Yang, Rong; Zhang, Guangyu

2017-02-01

Graphene has attracted extensive research interest in recent years because of its fascinating physical properties and its potential for various applications. The band structure or electronic properties of graphene are very sensitive to its geometry, size, and edge structures, especially when the size of graphene is below the quantum confinement limit. Graphene nanoribbons (GNRs) can be used as a model system to investigate such structure-sensitive parameters. In this review, we examine the fabrication of GNRs via both top-down and bottom-up approaches. The edge-related electronic and transport properties of GNRs are also discussed.

Locus equations and coarticulation in three Australian languages.

PubMed

Graetzer, Simone; Fletcher, Janet; Hajek, John

2015-02-01

Locus equations were applied to F2 data for bilabial, alveolar, retroflex, palatal, and velar plosives in three Australian languages. In addition, F2 variance at the vowel-consonant boundary, and, by extension, consonantal coarticulatory sensitivity, was measured. The locus equation slopes revealed that there were place-dependent differences in the magnitude of vowel-to-consonant coarticulation. As in previous studies, the non-coronal (bilabial and velar) consonants tended to be associated with the highest slopes, palatal consonants tended to be associated with the lowest slopes, and alveolar and retroflex slopes tended to be low to intermediate. Similarly, F2 variance measurements indicated that non-coronals displayed greater coarticulatory sensitivity to adjacent vowels than did coronals. Thus, both the magnitude of vowel-to-consonant coarticulation and the magnitude of consonantal coarticulatory sensitivity were seen to vary inversely with the magnitude of consonantal articulatory constraint. The findings indicated that, unlike results reported previously for European languages such as English, anticipatory vowel-to-consonant coarticulation tends to exceed carryover coarticulation in these Australian languages. Accordingly, on the F2 variance measure, consonants tended to be more sensitive to the coarticulatory effects of the following vowel. Prosodic prominence of vowels was a less significant factor in general, although certain language-specific patterns were observed.

Sensitivity Changes over the Course of Infection Increases the Likelihood of Resistance Against Fusion but Not CCR5 Receptor Blockers

PubMed Central

Chatziandreou, Nikolaos; Arauz, Ana Belen; Freitas, Ines; Nyein, Phyu Hninn; Fenton, Gregory; Mehta, Shruti H.; Kirk, Gregory D.

2012-01-01

Abstract As HIV-1 evolves over the course of infection, resistance against antiretrovirals may arise in the absence of drug pressure, especially against receptor and fusion blockers because of the extensive changes observed in the envelope glycoprotein. Here we show that viruses from the chronic phase of disease are significantly less sensitive to CCR5 receptor and fusion blockers compared to early infection variants. Differences in susceptibility to CCR5 antagonists were observed in spite of no demonstrable CXCR4 receptor utilization. No significant sensitivity differences were observed to another entry blocker, soluble CD4, or to reverse transcriptase, protease, or integrase inhibitors. Chronic as compared to early phase variants demonstrated greater replication when passaged in the presence of subinhibitory concentrations of fusion but not CCR5 receptor inhibitors. Fusion antagonist resistance, however, emerged from only one chronic phase virus culture. Because sensitivity to receptor and fusion antagonists is correlated with receptor affinity and fusion capacity, respectively, changes that occur in the envelope glycoprotein over the course of infection confer greater ability to use the CCR5 receptor and increased fusion ability. Our in vitro passage studies suggest that these evolving phenotypes increase the likelihood of resistance against fusion but not CCR5 receptor blockers. PMID:22650962

Multispectral photoacoustic tomography for detection of small tumors inside biological tissues

NASA Astrophysics Data System (ADS)

Hirasawa, Takeshi; Okawa, Shinpei; Tsujita, Kazuhiro; Kushibiki, Toshihiro; Fujita, Masanori; Urano, Yasuteru; Ishihara, Miya

2018-02-01

Visualization of small tumors inside biological tissue is important in cancer treatment because that promotes accurate surgical resection and enables therapeutic effect monitoring. For sensitive detection of tumor, we have been developing photoacoustic (PA) imaging technique to visualize tumor-specific contrast agents, and have already succeeded to image a subcutaneous tumor of a mouse using the contrast agents. To image tumors inside biological tissues, extension of imaging depth and improvement of sensitivity were required. In this study, to extend imaging depth, we developed a PA tomography (PAT) system that can image entire cross section of mice. To improve sensitivity, we discussed the use of the P(VDF-TrFE) linear array acoustic sensor that can detect PA signals with wide ranges of frequencies. Because PA signals produced from low absorbance optical absorbers shifts to low frequency, we hypothesized that the detection of low frequency PA signals improves sensitivity to low absorbance optical absorbers. We developed a PAT system with both a PZT linear array acoustic sensor and the P(VDF-TrFE) sensor, and performed experiment using tissue-mimicking phantoms to evaluate lower detection limits of absorbance. As a result, PAT images calculated from low frequency components of PA signals detected by the P(VDF-TrFE) sensor could visualize optical absorbers with lower absorbance.

Effect of Lagerstroemia tomentosa and Diospyros virginiana methanolic extracts on different drug-resistant strains of Mycobacterium tuberculosis

PubMed Central

Esfahani, B. Nasr; Hozoorbakhsh, F.; Rashed, Kh.; Havaei, S.A.; Heidari, K.; Moghim, Sh.

2014-01-01

Mycobacterium tuberculosis (MTB) is the causative agent of tuberculosis. The increasing incidence of multi drug resistance tuberculosis (MDR-TB) and extensively drug resistance tuberculosis (XDR-TB) worldwide highlighted the urgent need to search for alternative antimycobacterial agents. More and more people in developing countries utilize traditional medicine for their major primary health care needs. It has been determined that pharmaceutical plant, Lagerstroemia tomentosa and Diospyros virginiana, possesses some antibacterial effect. In this study, the antimycobacterial effects of L. tomentosa and D. virginiana methanolic extracts on sensitive and resistant isolates of MTB were examined. Leaf methanolic extract was prepared using methanol 70%. Sensitivity and resistance of isolates was determined by proportion method. The effects of two different methonolic extract concentrations (20 and 40 μg/ml) of the plants were examined against 6 sensitive and resistant strains of MTB with different patterns of drug resistance. MTB H37Rv (ATCC 27294) was set as control in all culturing and sensitivity testing processes. The results showed that L. tomentosa and D. virginiana methanolic extracts had weak inhibitory effect on different strains of MTB. The highest percentage of inhibition for L. tomentosa and D. virginiana was observed 38% and 33.3%, respectively. PMID:25657789

Diagnostic Accuracy, Sensitivity, and Specificity of Executive Function Tests in Moderate Traumatic Brain Injury in Ghana.

PubMed

Adjorlolo, Samuel

2018-06-01

The sociocultural differences between Western and sub-Saharan African countries make it imperative to standardize neuropsychological tests in the latter. However, Western-normed tests are frequently administered in sub-Saharan Africa because of challenges hampering standardization efforts. Yet a salient topical issue in the cross-cultural neuropsychology literature relates to the utility of Western-normed neuropsychological tests in minority groups, non-Caucasians, and by extension Ghanaians. Consequently, this study investigates the diagnostic accuracy, sensitivity, and specificity of executive function (EF) tests (The Stroop Test, Trail Making Test, and Controlled Oral Word Association Test), and a Revised Quick Cognitive Screening Test (RQCST) in a sample of 50 patients diagnosed with moderate traumatic brain injury and 50 healthy controls in Ghana. The EF test scores showed good diagnostic accuracy, with area under the curve (AUC) values of the Trail Making Test scores ranging from .746 to .902. With respect to the Stroop Test scores, the AUC values ranged from .793 to .898, while Controlled Oral Word Association Test had AUC value of .787. The RQCST scores discriminated between the groups, with AUC values ranging from .674 to .912. The AUC values of composite EF score and a neuropsychological score created from EF and RQCST scores were .936 and. 942, respectively. Additionally, the Stroop Test, Trail Making Test, EF composite score, and RQCST scores showed good to excellent sensitivities and specificities. In general, this study has shown that commonly used EF tests in Western countries have diagnostic accuracy, sensitivity, and specificity when administered in Ghanaian samples. The findings and implications of the study are discussed.

Transvaginal ultrasound versus magnetic resonance imaging for preoperative assessment of myometrial infiltration in patients with endometrial cancer: a systematic review and meta-analysis.

PubMed

Alcázar, Juan Luis; Gastón, Begoña; Navarro, Beatriz; Salas, Rocío; Aranda, Juana; Guerriero, Stefano

2017-11-01

To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for detecting myometrial infiltration (MI) in endometrial carcinoma. An extensive search of papers comparing TVS and MRI in assessing MI in endometrial cancer was performed in MEDLINE (PubMed), Web of Science, and Cochrane Database from January 1989 to January 2017. Quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Our extended search identified 747 citations but after exclusions we finally included in the meta-analysis 8 articles. The risk of bias for most studies was low for most 4 domains assessed in QUADAS-2. Overall, pooled estimated sensitivity and specificity for diagnosing deep MI were 75% (95% confidence interval [CI]=67%-82%) and 82% (95% CI=75%-93%) for TVS, and 83% (95% CI=76%-89%) and 82% (95% CI=72%-89%) for MRI, respectively. No statistical differences were found when comparing both methods (p=0.314). Heterogeneity was low for sensitivity and high for specificity for TVS and MRI. MRI showed a better sensitivity than TVS for detecting deep MI in women with endometrial cancer. However, the difference observed was not statistically significant. Copyright © 2017. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology

Transvaginal ultrasound versus magnetic resonance imaging for preoperative assessment of myometrial infiltration in patients with endometrial cancer: a systematic review and meta-analysis

PubMed Central

2017-01-01

Objective To compare the diagnostic accuracy of transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI) for detecting myometrial infiltration (MI) in endometrial carcinoma. Methods An extensive search of papers comparing TVS and MRI in assessing MI in endometrial cancer was performed in MEDLINE (PubMed), Web of Science, and Cochrane Database from January 1989 to January 2017. Quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Results Our extended search identified 747 citations but after exclusions we finally included in the meta-analysis 8 articles. The risk of bias for most studies was low for most 4 domains assessed in QUADAS-2. Overall, pooled estimated sensitivity and specificity for diagnosing deep MI were 75% (95% confidence interval [CI]=67%–82%) and 82% (95% CI=75%–93%) for TVS, and 83% (95% CI=76%–89%) and 82% (95% CI=72%–89%) for MRI, respectively. No statistical differences were found when comparing both methods (p=0.314). Heterogeneity was low for sensitivity and high for specificity for TVS and MRI. Conclusion MRI showed a better sensitivity than TVS for detecting deep MI in women with endometrial cancer. However, the difference observed was not statistically significant. PMID:29027404

The Efficacy of Guanxinning Injection in Treating Angina Pectoris: Systematic Review and Meta-Analysis of Randomized Controlled Trials

PubMed Central

Jia, Yongliang; Leung, Siu-wai; Lee, Ming-Yuen; Cui, Guozhen; Huang, Xiaohui; Pan, Fongha

2013-01-01

Objective. The randomized controlled trials (RCTs) on Guanxinning injection (GXN) in treating angina pectoris were published only in Chinese and have not been systematically reviewed. This study aims to provide a PRISMA-compliant and internationally accessible systematic review to evaluate the efficacy of GXN in treating angina pectoris. Methods. The RCTs were included according to prespecified eligibility criteria. Meta-analysis was performed to evaluate the symptomatic (SYMPTOMS) and electrocardiographic (ECG) improvements after treatment. Odds ratios (ORs) were used to measure effect sizes. Subgroup analysis, sensitivity analysis, and metaregression were conducted to evaluate the robustness of the results. Results. Sixty-five RCTs published between 2002 and 2012 with 6064 participants were included. Overall ORs comparing GXN with other drugs were 3.32 (95% CI: [2.72, 4.04]) in SYMPTOMS and 2.59 (95% CI: [2.14, 3.15]) in ECG. Subgroup analysis, sensitivity analysis, and metaregression found no statistically significant dependence of overall ORs upon specific study characteristics. Conclusion. This meta-analysis of eligible RCTs provides evidence that GXN is effective in treating angina pectoris. This evidence warrants further RCTs of higher quality, longer follow-up periods, larger sample sizes, and multicentres/multicountries for more extensive subgroup, sensitivity, and metaregression analyses. PMID:23634167

[Radiologic Presentation in Subspine Impingement and Correlation with Intraarticular Impingement in the Hip].

PubMed

Krüger, David R; Schütz, Michael; Perka, Carsten; Schröder, Jörg

2017-08-01

Background Besides the known intraarticular femoroacetabular impingement (FAI), recently forms of extra-articular impingement of the hip have been increasingly recognized. Recent studies have described an extra-articular impingement between a distal extension of the anterior inferior iliac spine (AIIS) and the femoral neck (AIIS or subspine impingement). Evidently, an association between this subspine impingement and an intraarticular FAI seems to exist. Little is known about the incidence of this impingement type and the value of its radiological diagnostics. The aim of this study was therefore to evaluate the correlation of a subspine impingement with intraarticular femoroacetabular impingement and radiological criteria of subspine impingement. Material and Methods In 2013 arthroscopic correction of intra-articular femoroacetabular impingement was performed in 80 cases. This collective was evaluated for simultaneous intraoperative findings of subspine impingement. In addition, the patients were evaluated for radiological signs of subspine impingement in conventional X-ray. A projection of the AIIS either below the acetabular sourcil or the anterior acetabular rim in an AP pelvis X-ray was considered as a radiological sign of low AIIS formation. These radiological findings were compared with the presence of intraoperative signs for subspine impingement, which are defined as a combination of focal capsule synovitis, labral ecchymosis close to the AIIS and a decreased offset between the acetabular rim and the AIIS. The specificity and sensitivity of the pre-operative radiological signs were calculated. Results A subspine impingement was found in 17 cases (21 %, 3 female, 14 male, mean age 28 years). A projection of the AIIS caudal to the acetabular sourcil in the AP pelvis X-ray was represented in 15 of the 17 cases detected (sensitivity 0.90, specificity 0.88). A projection below the anterior glenoid rim was detectable in 2 cases with symptomatic AIIS impingement (sensitivity 0.12, specificity 1). Conclusion A relevant proportion of patients with intraarticular FAI showed intraoperative signs for an additive extraarticular AIIS impingement. Preoperative pelvic X-rays are helpful with a sensitivity of 90 % in detecting the presence of a distal extension of the AIIS in FAI patients. Evaluation of the preoperative AP pelvis x-ray should include the projection of the AIIS. We recommend evaluation for subspine impingement during routine arthroscopy. Georg Thieme Verlag KG Stuttgart · New York.

A computer program for detailed analysis of the takeoff and approach performance capabilities of transport category aircraft

NASA Technical Reports Server (NTRS)

Foss, W. E., Jr.

1979-01-01

The takeoff and approach performance of an aircraft is calculated in accordance with the airworthiness standards of the Federal Aviation Regulations. The aircraft and flight constraints are represented in sufficient detail to permit realistic sensitivity studies in terms of either configuration modifications or changes in operational procedures. The program may be used to investigate advanced operational procedures for noise alleviation such as programmed throttle and flap controls. Extensive profile time history data are generated and are placed on an interface file which can be input directly to the NASA aircraft noise prediction program (ANOPP).

Reanalysis, compatibility and correlation in analysis of modified antenna structures

NASA Technical Reports Server (NTRS)

Levy, R.

1989-01-01

A simple computational procedure is synthesized to process changes in the microwave-antenna pathlength-error measure when there are changes in the antenna structure model. The procedure employs structural modification reanalysis methods combined with new extensions of correlation analysis to provide the revised rms pathlength error. Mainframe finite-element-method processing of the structure model is required only for the initial unmodified structure, and elementary postprocessor computations develop and deal with the effects of the changes. Several illustrative computational examples are included. The procedure adapts readily to processing spectra of changes for parameter studies or sensitivity analyses.

Kidnapping model: an extension of Selten's game.

PubMed

Iqbal, Azhar; Masson, Virginie; Abbott, Derek

2017-12-01

Selten's game is a kidnapping model where the probability of capturing the kidnapper is independent of whether the hostage has been released or executed. Most often, in view of the elevated sensitivities involved, authorities put greater effort and resources into capturing the kidnapper if the hostage has been executed, in contrast with the case when a ransom is paid to secure the hostage's release. In this paper, we study the asymmetric game when the probability of capturing the kidnapper depends on whether the hostage has been executed or not and find a new uniquely determined perfect equilibrium point in Selten's game.

Implementation of an experimental program to investigate the performance characteristics of OMEGA navigation

NASA Technical Reports Server (NTRS)

Baxa, E. G., Jr.

1974-01-01

A theoretical formulation of differential and composite OMEGA error is presented to establish hypotheses about the functional relationships between various parameters and OMEGA navigational errors. Computer software developed to provide for extensive statistical analysis of the phase data is described. Results from the regression analysis used to conduct parameter sensitivity studies on differential OMEGA error tend to validate the theoretically based hypothesis concerning the relationship between uncorrected differential OMEGA error and receiver separation range and azimuth. Limited results of measurement of receiver repeatability error and line of position measurement error are also presented.

Interaction of pH-sensitive non-phospholipid liposomes with cellular mimetic membranes.

PubMed

Marianecci, Carlotta; Rinaldi, Federica; Di Marzio, Luisa; Pozzi, Daniela; Caracciolo, Giulio; Manno, Daniela; Dini, Luciana; Paolino, Donatella; Celia, Christian; Carafa, Maria

2013-04-01

Surfactant nanocarriers have received considerable attention in the last several years as interesting alternative to classic liposomes. Different pH-sensitive vesicular colloidal carriers based on Tween 20 derivatives, obtained after functionalization of the head groups of the surfactant with natural, or simply modified, amino acids, were proposed as drug nanocarriers. Dynamic light scattering, Small Angle X-ray Scattering, Trasmission Electron Microscopy and fluorescence studies were used for the physico-chemical characterization of vesicles and mean size, size distribution, zeta potential, vesicle morphology and bilayer properties were evaluated. The pH-sensitivity and the stability of formulations, in absence and in presence of foetal bovine serum, were also evaluated. Moreover, the contact between surfactant vesicles and liposomes designed to model the cellular membrane was investigated by fluorescence studies to preliminary explore the potential interaction between vesicle and cell membranes. Experimental findings showed that physico-chemical and technological features of pH-sensitive vesicles were influenced by the composition of the carriers. Furthermore, proposed carriers are able to interact with mimetic cell membrane and it is reasonable to attribute the observed differences in interaction to the architectural/structural properties of Tween 20 derivatives. The findings reported in this investigation showed that a deep and extensive physico-chemical characterization of the carrier is a fundamental step, according to the evidence that the knowledge of nanocarrier properties is necessary to translate its potentiality to in vitro/in vivo applications.

A Genetic Basis for Mechanosensory Traits in Humans

PubMed Central

Frenzel, Henning; Bohlender, Jörg; Pinsker, Katrin; Wohlleben, Bärbel; Tank, Jens; Lechner, Stefan G.; Schiska, Daniela; Jaijo, Teresa; Rüschendorf, Franz; Saar, Kathrin; Jordan, Jens; Millán, José M.; Gross, Manfred; Lewin, Gary R.

2012-01-01

In all vertebrates hearing and touch represent two distinct sensory systems that both rely on the transformation of mechanical force into electrical signals. There is an extensive literature describing single gene mutations in humans that cause hearing impairment, but there are essentially none for touch. Here we first asked if touch sensitivity is a heritable trait and second whether there are common genes that influence different mechanosensory senses like hearing and touch in humans. Using a classical twin study design we demonstrate that touch sensitivity and touch acuity are highly heritable traits. Quantitative phenotypic measures of different mechanosensory systems revealed significant correlations between touch and hearing acuity in a healthy human population. Thus mutations in genes causing deafness genes could conceivably negatively influence touch sensitivity. In agreement with this hypothesis we found that a proportion of a cohort of congenitally deaf young adults display significantly impaired measures of touch sensitivity compared to controls. In contrast, blind individuals showed enhanced, not diminished touch acuity. Finally, by examining a cohort of patients with Usher syndrome, a genetically well-characterized deaf-blindness syndrome, we could show that recessive pathogenic mutations in the USH2A gene influence touch acuity. Control Usher syndrome cohorts lacking demonstrable pathogenic USH2A mutations showed no impairment in touch acuity. Our study thus provides comprehensive evidence that there are common genetic elements that contribute to touch and hearing and has identified one of these genes as USH2A. PMID:22563300

Egyptian plant species as new ozone indicators.

PubMed

Madkour, Samia A; Laurence, J A

2002-01-01

The aim of this study was to test and select one or more highly sensitive, specific and environmentally successful Egyptian bioindicator plants for ozone (O3). For that purpose more than 30 Egyptian species and cultivars were subjected to extensive screening studies under controlled environmental and pollutant exposure conditions to mimic the Egyptian environmental conditions and O3 levels in urban and rural sites. Four plant species were found to be more sensitive to O3 than the universally used O3-bioindicator, tobacco Bel W3, under the Egyptian environmental conditions used. These plant species, jute (Corchorus olitorius c.v. local), clover (Trifolium alexandrinum L. c.v. Masry), garden rocket (Eruca sativa c.v. local) and alfalfa (Medicago sativa L. c.v. local), ranked in order of decreasing sensitivity, exhibited typical O3 injury symptoms faster and at lower 03 concentrations than Bel W3. Three variables were tested in search of a reliable tool for the diagnosis and prediction of O3 response prior to the appearance of visible foliar symptoms: pigment degradation, stomatal conductance (g(s)) and net photosynthetic CO2 assimilation (Pnet). Pigment degradation was found to be unreliable in predicting species sensitivity to O3. Evidence supporting stomatal conductance involvement in 03 tolerance was found only in tolerant species. A good correlation was found between g(s), restriction of O3 and CO2 influx into the mesophyll tissues, and Pnet. Changes in Pnet seemed to depend largely on fluctuations in g(s).

Sensitivity computation of the ell1 minimization problem and its application to dictionary design of ill-posed problems

NASA Astrophysics Data System (ADS)

Horesh, L.; Haber, E.

2009-09-01

The ell1 minimization problem has been studied extensively in the past few years. Recently, there has been a growing interest in its application for inverse problems. Most studies have concentrated in devising ways for sparse representation of a solution using a given prototype dictionary. Very few studies have addressed the more challenging problem of optimal dictionary construction, and even these were primarily devoted to the simplistic sparse coding application. In this paper, sensitivity analysis of the inverse solution with respect to the dictionary is presented. This analysis reveals some of the salient features and intrinsic difficulties which are associated with the dictionary design problem. Equipped with these insights, we propose an optimization strategy that alleviates these hurdles while utilizing the derived sensitivity relations for the design of a locally optimal dictionary. Our optimality criterion is based on local minimization of the Bayesian risk, given a set of training models. We present a mathematical formulation and an algorithmic framework to achieve this goal. The proposed framework offers the design of dictionaries for inverse problems that incorporate non-trivial, non-injective observation operators, where the data and the recovered parameters may reside in different spaces. We test our algorithm and show that it yields improved dictionaries for a diverse set of inverse problems in geophysics and medical imaging.

Spatial resolution, contrast sensitivity, and sensitivity to defocus of chicken retinal ganglion cells in vitro.

PubMed

Diedrich, Erich; Schaeffel, Frank

2009-11-01

The chicken has been extensively studied as an animal model for myopia because its eye growth is tightly controlled by visual experience. It has been found that the retina controls the axial eye growth rates depending on the amount and the sign of defocus imposed in the projected image. Glucagonergic amacrine cells were discovered that appear to encode for the sign of imposed defocus. It is not clear whether the downstream neurons, the retinal ganglion cells, still have access to this information-and whether it ultimately reaches the brain. We have analyzed the spike rates of chicken retinal ganglion cells in vitro using a microelectrode array. For this purpose, we initially defined spatial resolution and contrast sensitivity in vitro. Two classes of chicken retinal ganglions were found, depending on the linearity of their responses with increasing contrast. Responses generally declined with increasing defocus of the visual stimulus. These responses were well predicted by the modulation transfer function for a diffraction-limited defocused optical system, the first Bessel function. Thus, the studied retinal ganglion cells did not distinguish between a loss of contrast at a given spatial frequency due to reduced contrast of the stimulus pattern or because the pattern was presented out of focus. Furthermore, there was no indication that the retinal ganglion cells responded differently to defocus of either sign, at least for the cells that were recorded in this study.

Recovery from Proactive Semantic Interference and MRI Volume: A Replication and Extension Study.

PubMed

Loewenstein, David A; Curiel, Rosie E; DeKosky, Steven; Rosselli, Monica; Bauer, Russell; Grieg-Custo, Maria; Penate, Ailyn; Li, Chunfei; Lizagarra, Gabriel; Golde, Todd; Adjouadi, Malek; Duara, Ranjan

2017-01-01

The rise in incidence of Alzheimer's disease (AD) has led to efforts to advance early detection of the disease during its preclinical stages. To achieve this, the field needs to develop more sensitive cognitive tests that relate to biological markers of disease pathology. Failure to recover from proactive interference (frPSI) is one such cognitive marker that is associated with volumetric reductions in the hippocampus, precuneus, and other AD-prone regions, and to amyloid load in the brain. The current study attempted to replicate and extend our previous findings that frPSI is a sensitive marker of early AD, and related to a unique pattern of volumetric loss in AD prone areas. Three different memory measures were examined relative to volumetric loss and cortical thickness among 45 participants with amnestic mild cognitive impairment. frPSI was uniquely associated with reduced volumes in the hippocampus (r = 0.50) precuneus (r = 0.41), and other AD prone regions, replicating previous findings. Strong associations between frPSI and lower entorhinal cortex volumes and cortical thickness (r≥0.60) and precuneus (r = 0.50) were also observed. Unique and strong associations between volumetric reductions and frPSI as observed by Loewenstein and colleagues were replicated. Together with cortical thickness findings, these results indicate that frPSI is worthy of further study as a sensitive and early cognitive marker of AD.

Real-Time Amperometric Recording of Extracellular H₂O₂ in the Brain of Immunocompromised Mice: An In Vitro, Ex Vivo and In Vivo Characterisation Study.

PubMed

Reid, Caroline H; Finnerty, Niall J

2017-07-08

We detail an extensive characterisation study on a previously described dual amperometric H₂O₂ biosensor consisting of H₂O₂ detection (blank) and degradation (catalase) electrodes. In vitro investigations demonstrated excellent H₂O₂ sensitivity and selectivity against the interferent, ascorbic acid. Ex vivo studies were performed to mimic physiological conditions prior to in vivo deployment. Exposure to brain tissue homogenate identified reliable sensitivity and selectivity recordings up to seven days for both blank and catalase electrodes. Furthermore, there was no compromise in pre- and post-implanted catalase electrode sensitivity in ex vivo mouse brain. In vivo investigations performed in anaesthetised mice confirmed the ability of the H₂O₂ biosensor to detect increases in amperometric current following locally perfused/infused H₂O₂ and antioxidant inhibitors mercaptosuccinic acid and sodium azide. Subsequent recordings in freely moving mice identified negligible effects of control saline and sodium ascorbate interference injections on amperometric H₂O₂ current. Furthermore, the stability of the amperometric current was confirmed over a five-day period and analysis of 24-h signal recordings identified the absence of diurnal variations in amperometric current. Collectively, these findings confirm the biosensor current responds in vivo to increasing exogenous and endogenous H₂O₂ and tentatively supports measurement of H₂O₂ dynamics in freely moving NOD SCID mice.

Electronic device increases threshold sensitivity and removes noise from FM communications receiver

NASA Technical Reports Server (NTRS)

Conrad, W. M.; Loch, F. J.

1971-01-01

Threshold extension device connected between demodulator output and filter output minimizes clicking noise. Device consists of click-eliminating signal transfer channel with follow-and-hold circuit and detector for sensing click impulses. Final output consists of signal plus low level noise without high amplitude impulses.

Theory into Practice: Advancing Normalization for the Child under Three

ERIC Educational Resources Information Center

Conklin-Moore, Alyssa

2017-01-01

Alyssa Conklin-Moore discusses normalization in the child under three from several perspectives. She takes an extensive look at the child, including orienting parents to the Montessori environment, the child's entrance into the environment, addressing the sensitive periods, and fostering independence, contribution, and community. She reminds the…

Linguistic and Cultural Factors Associated with Phonemic Fluency Performance in Bilingual Hispanics

ERIC Educational Resources Information Center

Bennett, Jennifer

2012-01-01

Verbal fluency tasks are used extensively in clinical settings because of their sensitivity to a wide variety of disorders, including cognitive decline and dementia, and their usefulness in differential diagnoses. However, the effects of bilingualism on neuropsychological assessment, and verbal fluency in particular, are currently not completely…

High gantry for lifting and handling

NASA Technical Reports Server (NTRS)

Kerley, J. J., Jr.; Tereniak, W. T.

1977-01-01

Standard gantry has been inexpensively modified with standard pipes to allow lifting of heavy loads to distances between 14 and 30 ft. Addition of air mounts permits extensive and sensitive equipment to be moved smoothly and safely over smooth or moderately rough surfaces. Unit has been tested at 6000 pounds without yielding.

GENE EXPRESSION PROFILING PROVIDES A SENSITIVE MEASURE OF EXPOSURE TO 17-A ETHINYLESTRADIOL IN THE FATHEAD MINNOW, PIMEPHALES PROMELAS

EPA Science Inventory

The freshwater fish, the fathead minnow (Pimephales promelas) represents an outstanding biological indicator response model organism based on its ubiquitous North American distribution and extensive use in acute and chronic testing of contaminants, effluents and receiving waters....

SIMULATING RADIONUCLIDE FATE AND TRANSPORT IN THE UNSATURATED ZONE: EVALUATION AND SENSITIVITY ANALYSES OF SELECT COMPUTER MODELS

EPA Science Inventory

Numerical, mathematical models of water and chemical movement in soils are used as decision aids for determining soil screening levels (SSLs) of radionuclides in the unsaturated zone. Many models require extensive input parameters which include uncertainty due to soil variabil...

Technologies for Learning.

ERIC Educational Resources Information Center

Meisler, Richard A.

As we experiment with uses of technology, we must resist a simplistic view of the venture. Technologies are more than means to ends. They change our goals, for they change our very natures as organisms. It is believed that educators cannot refrain from extensive technological innovation. In doing so, however, they must sensitize themselves to the…

The Intolerance of Uncertainty Index: Replication and Extension with an English Sample

ERIC Educational Resources Information Center

Carleton, R. Nicholas; Gosselin, Patrick; Asmundson, Gordon J. G.

2010-01-01

Intolerance of uncertainty (IU) is related to anxiety, depression, worry, and anxiety sensitivity. Precedent IU measures were criticized for psychometric instability and redundancy; alternative measures include the novel 45-item measure (Intolerance of Uncertainty Index; IUI). The IUI was developed in French with 2 parts, assessing general…

Epistemic Agency

ERIC Educational Resources Information Center

Elgin, Catherine Z.

2013-01-01

Virtue epistemologists hold that knowledge results from the display of epistemic virtues--open-mindedness, rigor, sensitivity to evidence, and the like. But epistemology cannot rest satisfied with a list of the virtues. What is wanted is a criterion for being an epistemic virtue. An extension of a formulation of Kant's categorical imperative…

Utility of an interferon-gamma release assay for latent tuberculosis diagnosis in a case of bullous pemphigoid.

PubMed

Goodfellow, Alfred; Keeling, Douglas N; Hayes, Robert C; Webster, Duncan

2009-01-01

With increasing use of immunosuppressive therapy, including tumor necrosis factor alpha inhibitors, there is concern about infectious complications, including reactivation of latent Mycobacterium tuberculosis infection. Routine testing prior to administration of systemic immunosuppression includes the tuberculin skin test, which lacks sensitivity and specificity and may be difficult to interpret in the presence of extensive cutaneous disease. Treatment of individuals with latent tuberculosis infection is recommended when immunosuppressive medications are to be employed. We report a case in which a diagnosis of latent tuberculosis infection in a patient with extensive bullous pemphigoid was clarified by the use of an interferon-gamma release assay after equivocal tuberculin skin test results. Interferon-gamma release assays are useful adjuncts to the tuberculin skin test in the diagnosis of latent tuberculosis infection in the setting of extensive cutaneous disease.

Photogrammetric registration of dental plaque accumulation in vivo.

PubMed

Bergström, J

1981-01-01

Using the labial surface of upper anterior laterals for determination, the accumulation of plaque was assessed by means of a stereo-photogrammetric method. The stereoimages were subjected to photogrammetric evaluation, the part of the surface area covered by plaque being given in per cent of the total surface area of the tooth. Plaque extension and plaque topography was studied in young adults with healthy periodontia during a 20 day period of no oral hygiene. At the end of the experimental period, on an average 75 per cent of the surface area was covered by plaque, corresponding to an extension rate of 3.75 per cent per day. The correlation between plaque values obtained by photogrammetry and various estimates obtained from clinical scoring ranged between r = 0.66 and r = 0.78. It is concluded that the method introduced is a sensitive means of determining small amounts of plaque and should prove useful for in vivo investigation of plaque growth and plaque suppression, where measurements of high quality is of importance.

Detection of different oxidation states of individual manganese porphyrins during their reaction with oxygen at a solid/liquid interface.

PubMed

den Boer, Duncan; Li, Min; Habets, Thomas; Iavicoli, Patrizia; Rowan, Alan E; Nolte, Roeland J M; Speller, Sylvia; Amabilino, David B; De Feyter, Steven; Elemans, Johannes A A W

2013-07-01

Manganese porphyrins have been extensively investigated as model systems for the natural enzyme cytochrome P450 and as synthetic oxidation catalysts. Here, we report single-molecule studies of the multistep reaction of manganese porphyrins with molecular oxygen at a solid/liquid interface, using a scanning tunnelling microscope (STM) under environmental control. The high lateral resolution of the STM, in combination with its sensitivity to subtle differences in the electronic properties of molecules, allowed the detection of at least four distinct reaction species. Real-space and real-time imaging of reaction dynamics enabled the observation of active sites, immobile on the experimental timescale. Conversions between the different species could be tuned by the composition of the atmosphere (argon, air or oxygen) and the surface bias voltage. By means of extensive comparison of the results to those obtained by analogous solution-based chemistry, we assigned the observed species to the starting compound, reaction intermediates and products.

Major advance of South Georgia glaciers during the Antarctic Cold Reversal following extensive sub-Antarctic glaciation

PubMed Central

Graham, Alastair G. C.; Kuhn, Gerhard; Meisel, Ove; Hillenbrand, Claus-Dieter; Hodgson, Dominic A.; Ehrmann, Werner; Wacker, Lukas; Wintersteller, Paul; dos Santos Ferreira, Christian; Römer, Miriam; White, Duanne; Bohrmann, Gerhard

2017-01-01

The history of glaciations on Southern Hemisphere sub-polar islands is unclear. Debate surrounds the extent and timing of the last glacial advance and termination on sub-Antarctic South Georgia in particular. Here, using sea-floor geophysical data and marine sediment cores, we resolve the record of glaciation offshore of South Georgia through the transition from the Last Glacial Maximum to Holocene. We show a sea-bed landform imprint of a shelf-wide last glacial advance and progressive deglaciation. Renewed glacier resurgence in the fjords between c. 15,170 and 13,340 yr ago coincided with a period of cooler, wetter climate known as the Antarctic Cold Reversal, revealing a cryospheric response to an Antarctic climate pattern extending into the Atlantic sector of the Southern Ocean. We conclude that the last glaciation of South Georgia was extensive, and the sensitivity of its glaciers to climate variability during the last termination more significant than implied by previous studies. PMID:28303885

Growth responses of low-alpine dwarf-shrub heath species to nitrogen deposition and management.

PubMed

Britton, Andrea J; Fisher, Julia M

2008-06-01

Nitrogen deposition is a continuing problem in European alpine regions. We hypothesised that, despite climatic limitations, low-alpine Calluna heathland would respond to nitrogen addition with increased shoot growth and flowering and that fire and grazing would modify responses. In a five-year study, 0-50kgNha(-1)y(-1) were added, combined with burning (+/-) and clipping (+/-). Calluna vulgaris responded with increased shoot extension, but effects on flowering were variable. Burning enhanced the positive effect of nitrogen addition and negative effects of clipping. Sub-dominant shrubs generally did not respond to nitrogen. C. vulgaris shoot extension was stimulated by nitrogen addition of 10kgNha(-1)y(-1) (above background) supporting suggestions that alpine heathlands are sensitive to low levels of nitrogen deposition. Increased C. vulgaris growth could negatively impact on important lichen components of this vegetation through increased shading and competition. Climatic factors constrain productivity in this community, but do not prevent rapid responses to nitrogen deposition by some species.

Electrode position markedly affects knee torque in tetanic, stimulated contractions.

PubMed

Vieira, Taian M; Potenza, Paolo; Gastaldi, Laura; Botter, Alberto

2016-02-01

The purpose of this study was to investigate how much the distance between stimulation electrodes affects the knee extension torque in tetanic, electrically elicited contractions. Current pulses of progressively larger amplitude, from 0 mA to maximally tolerated intensities, were delivered at 20 pps to the vastus medialis, rectus femoris and vastus lateralis muscles of ten, healthy male subjects. Four inter-electrode distances were tested: 32.5% (L1), 45.0% (L2), 57.5% (L3) and 70% (L4) of the distance between the patella apex and the anterior superior iliac spine. The maximal knee extension torque and the current leading to the maximal torque were measured and compared between electrode configurations. The maximal current tolerated by each participant ranged from 60 to 100 mA and did not depend on the inter-electrode distance. The maximal knee extension torque elicited did not differ between L3 and L4 (P = 0.15) but, for both conditions, knee torque was significantly greater than for L1 and L2 (P < 0.024). On average, the extension torque elicited for L3 and L4 was two to three times greater than that obtained for L1 and L2. The current leading to maximal torque was not as sensitive to inter-electrode distance. Except for L1 current intensity did not change with electrode configuration (P > 0.16). Key results presented here revealed that for a given stimulation intensity, knee extension torque increased dramatically with the distance between electrodes. The distance between electrodes seems therefore to critically affect knee torque, with potential implication for optimising exercise protocols based on electrical stimulation.

Critical loads of atmospheric deposition to Adirondack lake watersheds: A guide for policymakers

USGS Publications Warehouse

Burns, Douglas A.; Sullivan, Timothy J.

2015-01-01

Acid deposition is sometimes referred to as “acid rain,” although part of the acid load reaches the surface by means other than rainfall. In the eastern U.S., acid deposition consists of several forms of sulfur and nitrogen that largely originate as emissions to the atmosphere from sources such as electricity-generating facilities (coal, oil, and natural gas), diesel- and gasoline-burning vehicles, some agricultural activities, and smokestack industries. Acid deposition is known to cause deleterious effects to sensitive ecosystems of which the Adirondack region of New York State provides several well-known and well-studied examples. This largely forested region includes abundant lakes, streams, and wetlands and possesses several landscape features that result in high ecosystem sensitivity to acid deposition. These features include bedrock that weathers slowly, steep slopes, and thin, naturally acidic soils. An ecosystem is described as sensitive to, or affected by, acid deposition if prolonged exposure to acid deposition has resulted in detrimental ecosystem effects. Soils, streams, and lakes that are less sensitive are better able to buffer acid deposition. A principal reason that acidification is a concern for resource managers is because of the changes induced in native biota and their habitat on land and in water. As the chemistry of soils and surface waters in sensitive landscapes changes in response to prolonged exposure to acid deposition, organisms that cannot tolerate high acidity, such as sugar maple trees and many species of fish and aquatic insects, may be gradually eliminated from the ecosystem. Other biota such as red spruce may experience increased stress and reduced growth rates as a result of acidification, exposing these species to increased susceptibility to disease and other natural stressors and perhaps increased mortality. The ecological effects of acid deposition have been documented by extensive research that began in the U.S. in the 1970s and continues today. This report does not provide a detailed discussion of these ecological effects, but interested readers can refer to four publications that provide good summaries of current scientific knowledge of these effects, including extensive reference to previous research in the Adirondacks (Driscoll et al. 2001, Jenkins et al. 2007, Burns et al. 2011, Sullivan 2015).

Mercury orbiter transport study

NASA Technical Reports Server (NTRS)

Friedlander, A. L.; Feingold, H.

1977-01-01

A data base and comparative performance analyses of alternative flight mode options for delivering a range of payload masses to Mercury orbit are provided. Launch opportunities over the period 1980-2000 are considered. Extensive data trades are developed for the ballistic flight mode option utilizing one or more swingbys of Venus. Advanced transport options studied include solar electric propulsion and solar sailing. Results show the significant performance tradeoffs among such key parameters as trip time, payload mass, propulsion system mass, orbit size, launch year sensitivity and relative cost-effectiveness. Handbook-type presentation formats, particularly in the case of ballistic mode data, provide planetary program planners with an easily used source of reference information essential in the preliminary steps of mission selection and planning.

Sleep extension is a feasible lifestyle intervention in free-living adults who are habitually short sleepers: a potential strategy for decreasing intake of free sugars? A randomized controlled pilot study

PubMed Central

Al Khatib, Haya K; Hall, Wendy L; Creedon, Alice; Ooi, Emily; Masri, Tala; McGowan, Laura; Harding, Scott V; Darzi, Julia; Pot, Gerda K

2018-01-01

ABSTRACT Background Evidence suggests that short sleep duration may be a newly identified modifiable risk factor for obesity, yet there is a paucity of studies to investigate this. Objective We assessed the feasibility of a personalized sleep extension protocol in adults aged 18–64 y who are habitually short sleepers (5 to <7 h), with sleep primarily measured by wrist actigraphy. In addition, we collected pilot data to assess the effects of extended sleep on dietary intake and quality measured by 7-d food diaries, resting and total energy expenditure, physical activity, and markers of cardiometabolic health. Design Forty-two normal-weight healthy participants who were habitually short sleepers completed this free-living, 4-wk, parallel-design randomized controlled trial. The sleep extension group (n = 21) received a behavioral consultation session targeting sleep hygiene. The control group (n = 21) maintained habitual short sleep. Results Rates of participation, attrition, and compliance were 100%, 6.5%, and 85.7%, respectively. The sleep extension group significantly increased time in bed [0:55 hours:minutes (h:mm); 95% CI: 0:37, 1:12 h:mm], sleep period (0:47 h:mm; 95% CI: 0:29, 1:05 h:mm), and sleep duration (0:21 h:mm; 95% CI: 0:06, 0:36 h:mm) compared with the control group. Sleep extension led to reduced intake of free sugars (–9.6 g; 95% CI: –16.0, –3.1 g) compared with control (0.7 g; 95% CI: –5.7, 7.2 g) (P = 0.042). A sensitivity analysis in plausible reporters showed that the sleep extension group reduced intakes of fat (percentage), carbohydrates (grams), and free sugars (grams) in comparison to the control group. There were no significant differences between groups in markers of energy balance or cardiometabolic health. Conclusions We showed the feasibility of extending sleep in adult short sleepers. Sleep extension led to reduced free sugar intakes and may be a viable strategy to facilitate limiting excessive consumption of free sugars in an obesity-promoting environment. This trial was registered at www.clinicaltrials.gov as NCT02787577. PMID:29381788

Revisiting inconsistency in large pharmacogenomic studies

PubMed Central

Safikhani, Zhaleh; Smirnov, Petr; Freeman, Mark; El-Hachem, Nehme; She, Adrian; Rene, Quevedo; Goldenberg, Anna; Birkbak, Nicolai J.; Hatzis, Christos; Shi, Leming; Beck, Andrew H.; Aerts, Hugo J.W.L.; Quackenbush, John; Haibe-Kains, Benjamin

2017-01-01

In 2013, we published a comparative analysis of mutation and gene expression profiles and drug sensitivity measurements for 15 drugs characterized in the 471 cancer cell lines screened in the Genomics of Drug Sensitivity in Cancer (GDSC) and Cancer Cell Line Encyclopedia (CCLE). While we found good concordance in gene expression profiles, there was substantial inconsistency in the drug responses reported by the GDSC and CCLE projects. We received extensive feedback on the comparisons that we performed. This feedback, along with the release of new data, prompted us to revisit our initial analysis. We present a new analysis using these expanded data, where we address the most significant suggestions for improvements on our published analysis — that targeted therapies and broad cytotoxic drugs should have been treated differently in assessing consistency, that consistency of both molecular profiles and drug sensitivity measurements should be compared across cell lines, and that the software analysis tools provided should have been easier to run, particularly as the GDSC and CCLE released additional data. Our re-analysis supports our previous finding that gene expression data are significantly more consistent than drug sensitivity measurements. Using new statistics to assess data consistency allowed identification of two broad effect drugs and three targeted drugs with moderate to good consistency in drug sensitivity data between GDSC and CCLE. For three other targeted drugs, there were not enough sensitive cell lines to assess the consistency of the pharmacological profiles. We found evidence of inconsistencies in pharmacological phenotypes for the remaining eight drugs. Overall, our findings suggest that the drug sensitivity data in GDSC and CCLE continue to present challenges for robust biomarker discovery. This re-analysis provides additional support for the argument that experimental standardization and validation of pharmacogenomic response will be necessary to advance the broad use of large pharmacogenomic screens. PMID:28928933

Improving detection of HIV-associated cognitive impairment: Comparison of the International HIV Dementia Scale and a Brief Screening Battery

PubMed Central

de Almeida, Sergio Monteiro; Kamat, Rujvi; Cherner, Mariana; Umlauf, Anya; Ribeiro, Clea Elisa; de Pereira, Ana Paula; Franklin, Donald; Heaton, Robert K.; Ellis, Ronald J.

2016-01-01

Objectives The International HIV Dementia Scale (IHDS) was developed to screen for HIV-associated dementia (HAD), but it has been used more generally for HIV-associated neurocognitive disorder (HAND). This study sought to examine the accuracy of the IHDS in a cohort of Brazilian HIV-infected individuals and compare its performance to an alternative screening battery for detecting HAND. Methods 108 participants (including 60 HIV-infected persons), completed the IHDS and a gold standard neuropsychological (NP) battery of 17 tests. As alternative screening method, all possible three-test combinations from the NP battery were examined and a superiority index (a marker of specificity and sensitivity) was calculated. Results Sensitivity and specificity to HAND using the standard IHDS cutpoint of 10 were 36% and 75% respectively. The best balance between sensitivity and specificity was accomplished with a modified cutpoint of 11.5, which yielded sensitivity of 72% and specificity of 58%. The top two most sensitive test combinations, compared to the gold standard NP battery, were Trail Making Test A, WAIS-III Digit Symbol (DS) and HVLT-R Total Recall (sensitivity 91%, specificity 96%), and DS, BVMT-R Total Recall and Grooved Pegboard Test-Dominant Hand (sensitivity 94%, specificity 91%). Conclusions Both test combinations can be administered in under 10 minutes and were more accurate than the IHDS in classifying HIV+ participants as NP impaired or unimpaired. These data suggest that demographically corrected T-scores from commonly used NP measures with modest time and material demands can improve identification of patients with HAND who may benefit from a more extensive NP examination. PMID:27828876

Improving Detection of HIV-Associated Cognitive Impairment: Comparison of the International HIV Dementia Scale and a Brief Screening Battery.

PubMed

de Almeida, Sérgio Monteiro; Kamat, Rujvi; Cherner, Mariana; Umlauf, Anya; Ribeiro, Clea E; de Pereira, Ana Paula; Franklin, Donald; Heaton, Robert K; Ellis, Ronald J

2017-03-01

The International HIV Dementia Scale (IHDS) was developed to screen for HIV-associated dementia, but it has been used more generally for HIV-associated neurocognitive disorder (HAND). This study sought to examine the accuracy of the IHDS in a cohort of Brazilian HIV-infected individuals and compare its performance to an alternative screening battery for detecting HAND. A total of 108 participants (including 60 HIV-infected persons) completed the IHDS and a gold standard neuropsychological (NP) battery of 17 tests. As alternative screening method, all possible 3-test combinations from the NP battery were examined and a superiority index (a marker of specificity and sensitivity) was calculated. Sensitivity and specificity to HAND using the standard IHDS cutpoint of 10 were 36% and 75%, respectively. The best balance between sensitivity and specificity was accomplished with a modified cutpoint of 11.5, which yielded sensitivity of 72% and specificity of 58%. The top two most sensitive test combinations, compared with the gold standard NP battery, were Trail Making Test A, Wechsler Adult Intelligence Scale III Digit Symbol and Hopkins Verbal Learning Test-Revised Total Recall (sensitivity 91%, specificity 96%), and Digit Symbol, Brief Visuospatial Memory Test-Revised Total Recall and Grooved Pegboard Test-dominant hand (sensitivity 94%, specificity 91%). Both test combinations can be administered in less than 10 minutes and were more accurate than the IHDS in classifying HIV+ participants as NP impaired or unimpaired. These data suggest that demographically corrected T-scores from commonly used NP measures with modest time and material demands can improve identification of patients with HAND who may benefit from a more extensive NP examination.

Sensitivity of subject-specific models to errors in musculo-skeletal geometry.

PubMed

Carbone, V; van der Krogt, M M; Koopman, H F J M; Verdonschot, N

2012-09-21

Subject-specific musculo-skeletal models of the lower extremity are an important tool for investigating various biomechanical problems, for instance the results of surgery such as joint replacements and tendon transfers. The aim of this study was to assess the potential effects of errors in musculo-skeletal geometry on subject-specific model results. We performed an extensive sensitivity analysis to quantify the effect of the perturbation of origin, insertion and via points of each of the 56 musculo-tendon parts contained in the model. We used two metrics, namely a Local Sensitivity Index (LSI) and an Overall Sensitivity Index (OSI), to distinguish the effect of the perturbation on the predicted force produced by only the perturbed musculo-tendon parts and by all the remaining musculo-tendon parts, respectively, during a simulated gait cycle. Results indicated that, for each musculo-tendon part, only two points show a significant sensitivity: its origin, or pseudo-origin, point and its insertion, or pseudo-insertion, point. The most sensitive points belong to those musculo-tendon parts that act as prime movers in the walking movement (insertion point of the Achilles Tendon: LSI=15.56%, OSI=7.17%; origin points of the Rectus Femoris: LSI=13.89%, OSI=2.44%) and as hip stabilizers (insertion points of the Gluteus Medius Anterior: LSI=17.92%, OSI=2.79%; insertion point of the Gluteus Minimus: LSI=21.71%, OSI=2.41%). The proposed priority list provides quantitative information to improve the predictive accuracy of subject-specific musculo-skeletal models. Copyright © 2012 Elsevier Ltd. All rights reserved.

Anxiety sensitivity and intolerance of uncertainty as potential risk factors for cyberchondria: A replication and extension examining dimensions of each construct.

PubMed

Fergus, Thomas A

2015-09-15

Preliminary findings suggest that anxiety sensitivity (AS) and intolerance of uncertainty (IU) may confer vulnerability for cyberchondria, defined as repeated internet searches for medical information that exacerbates health anxiety. Prior studies are limited because it remains unclear whether specific AS or IU dimensions differentially relate to certain cyberchondria dimensions. The present study examined associations among AS, IU, and cyberchondria dimensions using a sample of community adults (N = 578) located in the United States. As predicted, physical AS and inhibitory IU were the only AS or IU dimensions to share unique associations with the distress cyberchondria dimension after controlling for the overlap among the AS dimensions, IU dimensions, and health anxiety. Cognitive AS and social AS unexpectedly evidenced unique associations with cyberchondria dimensions. The results are limited by the cross-sectional study design and use of a community, rather than clinical, sample. This study provides evidence that specific AS and IU dimensions may confer vulnerability to certain cyberchondria dimensions. Further clarifying associations among AS, IU, and cyberchondria may lead to improvements in our conceptualization and, ultimately, treatment of cyberchondria. Copyright © 2015 Elsevier B.V. All rights reserved.

The financial attractiveness assessment of large waste management projects registered as clean development mechanism

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

Bufoni, André Luiz, E-mail: bufoni@facc.ufrj.br; Oliveira, Luciano Basto; Rosa, Luiz Pinguelli

Highlights: • Projects are not financially attractive without registration as CDMs. • WM benchmarks and indicators are converging and reducing in variance. • A sensitivity analysis reveal that revenue has more of an effect on the financial results. • Results indicate that an extensive database would reduce WM project risk and capital costs. • Disclosure standards would make information more comparable worldwide. - Abstract: This study illustrates the financial analyses for demonstration and assessment of additionality presented in the project design (PDD) and enclosed documents of the 431 large Clean Development Mechanisms (CDM) classified as the ‘waste handling and disposalmore » sector’ (13) over the past ten years (2004–2014). The expected certified emissions reductions (CER) of these projects total 63.54 million metric tons of CO{sub 2}eq, where eight countries account for 311 projects and 43.36 million metric tons. All of the projects declare themselves ‘not financially attractive’ without CER with an estimated sum of negative results of approximately a half billion US$. The results indicate that WM benchmarks and indicators are converging and reducing in variance, and the sensitivity analysis reveals that revenues have a greater effect on the financial results. This work concludes that an extensive financial database with simple standards for disclosure would greatly diminish statement problems and make information more comparable, reducing the risk and capital costs of WM projects.« less

Learning from Higgs physics at future Higgs factories

NASA Astrophysics Data System (ADS)

Gu, Jiayin; Li, Honglei; Liu, Zhen; Su, Shufang; Su, Wei

2017-12-01

Future Higgs factories can reach impressive precision on Higgs property measurements. In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explore its sensitivity to new physics models at the electron-positron colliders. In particular, we study two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weakly-interacting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong interacting models as examples of strong dynamics. We perform a global fit to various Higgs search channels to obtain the 95% C.L. constraints on the model parameter space. In the SM with a singlet extension, we obtain the limits on the singlet-doublet mixing angle sin θ, as well as the more general Wilson coefficients of the induced higher dimensional operators. In the 2HDM, we analyze tree level effects in tan β vs. cos( β - α) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for different types of 2HDM. In strong dynamics models, we obtain lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish different models. We also compare the sensitivity of various future Higgs factories, namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).

Human Leukocyte Antigen Class II Transgenic Mouse Model Unmasks the Significant Extrahepatic Pathology in Toxic Shock Syndrome

PubMed Central

Tilahun, Ashenafi Y.; Marietta, Eric V.; Wu, Tsung-Teh; Patel, Robin; David, Chella S.; Rajagopalan, Govindarajan

2011-01-01

Among the exotoxins produced by Staphylococcus aureus and Streptococcus pyogenes, the superantigens (SAgs) are the most potent T-cell activators known to date. SAgs are implicated in several serious diseases including toxic shock syndrome (TSS), Kawasaki disease, and sepsis. However, the immunopathogenesis of TSS and other diseases involving SAgs are still not completely understood. The commonly used conventional laboratory mouse strains do not respond robustly to SAgs in vivo. Therefore, they must be artificially rendered susceptible to TSS by using sensitizing agents such as d-galactosamine (d-galN), which skews the disease exclusively to the liver and, hence, is not representative of the disease in humans. SAg-induced TSS was characterized using transgenic mice expressing HLA class II molecules that are extremely susceptible to TSS without d-galN. HLA-DR3 transgenic mice recapitulated TSS in humans with extensive multiple-organ inflammation affecting the lung, liver, kidneys, heart, and small intestines. Heavy infiltration with T lymphocytes (both CD4+ and CD8+), neutrophils, and macrophages was noted. In particular, the pathologic changes in the small intestines were extensive and accompanied by significantly altered absorptive functions of the enterocytes. In contrast to massive liver failure alone in the d-galN sensitization model of TSS, findings of the present study suggest that gut dysfunction might be a key pathogenic event that leads to high morbidity and mortality in humans with TSS. PMID:21641398

Brief group training of medical students in focused cardiac ultrasound may improve diagnostic accuracy of physical examination.

PubMed

Stokke, Thomas M; Ruddox, Vidar; Sarvari, Sebastian I; Otterstad, Jan E; Aune, Erlend; Edvardsen, Thor

2014-11-01

Physical examination and auscultation can be challenging for medical students. The aim of this study was to investigate whether a brief session of group training in focused cardiac ultrasound (FCU) with a pocket-sized device would allow medical students to improve their ability to detect clinically relevant cardiac lesions at the bedside. Twenty-one medical students in their clinical curriculum completed 4 hours of FCU training in groups. The students examined patients referred for echocardiography with emphasis on auscultation, followed by FCU. Findings from physical examination and FCU were compared with those from standard echocardiography performed and analyzed by cardiologists. In total, 72 patients were included in the study, and 110 examinations were performed. With a stethoscope, sensitivity to detect clinically relevant (moderate or greater) valvular disease was 29% for mitral regurgitation, 33% for aortic regurgitation, and 67% for aortic stenosis. FCU improved sensitivity to detect mitral regurgitation (69%, P < .001). However, sensitivity to detect aortic regurgitation (43%) and aortic stenosis (70%) did not improve significantly. Specificity was ≥89% for all valvular diagnoses by both methods. For nonvalvular diagnoses, FCU's sensitivity to detect moderate or greater left ventricular dysfunction (90%) was excellent, detection of right ventricular dysfunction (79%) was good, while detection of dilated left atrium (53%), dilated right atrium (49%), pericardial effusion (40%), and dilated aortic root (25%) was less accurate. Specificity varied from 57% to 94%. After brief group training in FCU, medical students could detect mitral regurgitation significantly better compared with physical examination, whereas detection of aortic regurgitation and aortic stenosis did not improve. Left ventricular dysfunction was detected with high sensitivity. More extensive training is advised. Copyright © 2014 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

Prevalence of occupational allergy to bell pepper pollen in greenhouses in the Netherlands.

PubMed

Groenewoud, G C M; de Jong, N W; van Oorschot-van Nes, A J; Vermeulen, A M; van Toorenenbergen, A W; Mulder, P G H; Burdorf, A; de Groot, H; van Wijk, R Gerth

2002-03-01

An increasing number of allergic complaints appear to have occurred among bell pepper greenhouse employees. The aim of this study was to estimate the prevalence of work-related allergic symptoms and the prevalence of sensitization to specific occupational allergens and its determinants. We studied 472 employees who were invited to answer an extensive questionnaire and to be tested on location with inhalant allergens and home-made extracts of the bell pepper plant. In addition, peak expiratory flow monitoring and RASTs were performed. Work-related symptoms were reported in 53.8% of all cases. Sensitization to the bell pepper plant was found in 35.4%. Positive reactions to leaf, stem and/or juice, however, were associated in nearly 90% with sensitization to pollen, which appeared to be most important allergen of the plant. Sensitization to the bell pepper plant and inhalant atopy were considered the most important risk factors for the occurrence of work-related symptoms of the upper airways (PRR 2.63, CI 2.11-3.25 and PRR 2.25, CI 1.82-2.79) as well as of the lower airways (PRR 4.08, CI 2.38-7.00 and PRR 3.16, CI 1.87-5.33). There is a surprisingly high prevalence of work-related respiratory symptoms (53.8%) in bell pepper horticulture. In two-thirds of the employees, symptoms at work were associated with an IgE-mediated allergy due to the high and chronic exposure to bell pepper pollen. Complaints at work without specific sensitization to bell pepper pollen can be caused by non-specific hyper-reactivity or atopy to other occupational allergens. The extent of this occupational allergy has important consequences for the health care of this large, still growing occupational group.

Escitalopram in the Treatment of Adolescent Depression: A Randomized, Double-Blind, Placebo-Controlled Extension Trial

PubMed Central

Robb, Adelaide; Bose, Anjana

2013-01-01

Abstract Objective The purpose of this study was to evaluate the extended efficacy, safety, and tolerability of escitalopram relative to placebo in adolescents with major depressive disorder (MDD). Methods Adolescents (12–17 years) who completed an 8-week randomized, double-blind, flexible-dose, placebo-controlled, lead-in study of escitalopram 10–20 mg versus placebo could enroll in a 16–24-week, multisite extension trial; patients maintained the same lead-in randomization (escitalopram or placebo) and dosage (escitalopram 10 or 20 mg/day, or placebo) during the extension. The primary efficacy was Children's Depression Rating Scale-Revised (CDRS-R) change from the lead-in study baseline to treatment week 24 (8-week lead-in study plus 16-week extension); the secondary efficacy was Clinical Global Impressions-Improvement (CGI-I) score at week 24. All efficacy analyses used the last observation carried forward (LOCF) approach; sensitivity analyses used observed cases (OC) and mixed-effects model for repeated measures (MMRM). Safety was evaluated via adverse event (AE) reports and the clinician-rated Columbia-Suicide Severity Rating Scale (C-SSRS). Results Following lead-in, 165 patients enrolled in the double-blind extension (82 placebo; 83 escitalopram); 40 (48.8%) placebo and 37 (44.6%) escitalopram patients completed treatment. CDRS-R total score improvement was significantly greater for escitalopram than for placebo (p=0.005, LOCF; p=0.014; MMRM). Response rates (CDRS-R ≥40% reduction from baseline [adjusted and unadjusted] and CGI-I ≤2) were significantly higher for escitalopram than for placebo (LOCF); remission rates (CDRS-R ≤28) were 50.6% for escitalopram and 35.7% for placebo (p=0.002). OC analyses were not significantly different between groups. The most frequent escitalopram AEs (≥5% and more frequent than placebo) were headache, nausea, insomnia, vomiting, influenza-like symptoms, diarrhea, and urinary tract infection. Most AEs were mild/moderate and not related to the study drug. AEs suggestive of self-harm occurred in 5.7% and 7.1% of placebo and escitalopram patients. Occurrence of suicidal behavior and/or suicidal ideation assessed by C-SSRS was 10.9% (14/128) for placebo and 14.5% (19/131) for escitalopram. Conclusions Extended use of escitalopram was generally safe and resulted in modest improvement in efficacy in adolescents with MDD. PMID:24041408

Escitalopram in the treatment of adolescent depression: a randomized, double-blind, placebo-controlled extension trial.

PubMed

Findling, Robert L; Robb, Adelaide; Bose, Anjana

2013-09-01

The purpose of this study was to evaluate the extended efficacy, safety, and tolerability of escitalopram relative to placebo in adolescents with major depressive disorder (MDD). Adolescents (12-17 years) who completed an 8-week randomized, double-blind, flexible-dose, placebo-controlled, lead-in study of escitalopram 10-20 mg versus placebo could enroll in a 16-24-week, multisite extension trial; patients maintained the same lead-in randomization (escitalopram or placebo) and dosage (escitalopram 10 or 20 mg/day, or placebo) during the extension. The primary efficacy was Children's Depression Rating Scale-Revised (CDRS-R) change from the lead-in study baseline to treatment week 24 (8-week lead-in study plus 16-week extension); the secondary efficacy was Clinical Global Impressions-Improvement (CGI-I) score at week 24. All efficacy analyses used the last observation carried forward (LOCF) approach; sensitivity analyses used observed cases (OC) and mixed-effects model for repeated measures (MMRM). Safety was evaluated via adverse event (AE) reports and the clinician-rated Columbia-Suicide Severity Rating Scale (C-SSRS). Following lead-in, 165 patients enrolled in the double-blind extension (82 placebo; 83 escitalopram); 40 (48.8%) placebo and 37 (44.6%) escitalopram patients completed treatment. CDRS-R total score improvement was significantly greater for escitalopram than for placebo (p=0.005, LOCF; p=0.014; MMRM). Response rates (CDRS-R ≥ 40% reduction from baseline [adjusted and unadjusted] and CGI-I ≤ 2) were significantly higher for escitalopram than for placebo (LOCF); remission rates (CDRS-R ≤ 28) were 50.6% for escitalopram and 35.7% for placebo (p=0.002). OC analyses were not significantly different between groups. The most frequent escitalopram AEs (≥ 5% and more frequent than placebo) were headache, nausea, insomnia, vomiting, influenza-like symptoms, diarrhea, and urinary tract infection. Most AEs were mild/moderate and not related to the study drug. AEs suggestive of self-harm occurred in 5.7% and 7.1% of placebo and escitalopram patients. Occurrence of suicidal behavior and/or suicidal ideation assessed by C-SSRS was 10.9% (14/128) for placebo and 14.5% (19/131) for escitalopram. Extended use of escitalopram was generally safe and resulted in modest improvement in efficacy in adolescents with MDD.

Computer-animated stimuli to measure motion sensitivity: constraints on signal design in the Jacky dragon.

PubMed

Woo, Kevin L; Rieucau, Guillaume; Burke, Darren

2017-02-01

Identifying perceptual thresholds is critical for understanding the mechanisms that underlie signal evolution. Using computer-animated stimuli, we examined visual speed sensitivity in the Jacky dragon Amphibolurus muricatus , a species that makes extensive use of rapid motor patterns in social communication. First, focal lizards were tested in discrimination trials using random-dot kinematograms displaying combinations of speed, coherence, and direction. Second, we measured subject lizards' ability to predict the appearance of a secondary reinforcer (1 of 3 different computer-generated animations of invertebrates: cricket, spider, and mite) based on the direction of movement of a field of drifting dots by following a set of behavioural responses (e.g., orienting response, latency to respond) to our virtual stimuli. We found an effect of both speed and coherence, as well as an interaction between these 2 factors on the perception of moving stimuli. Overall, our results showed that Jacky dragons have acute sensitivity to high speeds. We then employed an optic flow analysis to match the performance to ecologically relevant motion. Our results suggest that the Jacky dragon visual system may have been shaped to detect fast motion. This pre-existing sensitivity may have constrained the evolution of conspecific displays. In contrast, Jacky dragons may have difficulty in detecting the movement of ambush predators, such as snakes and of some invertebrate prey. Our study also demonstrates the potential of the computer-animated stimuli technique for conducting nonintrusive tests to explore motion range and sensitivity in a visually mediated species.

Evaluation and construction of diagnostic criteria for inclusion body myositis

PubMed Central

Mammen, Andrew L.; Amato, Anthony A.; Weiss, Michael D.; Needham, Merrilee

2014-01-01

Objective: To use patient data to evaluate and construct diagnostic criteria for inclusion body myositis (IBM), a progressive disease of skeletal muscle. Methods: The literature was reviewed to identify all previously proposed IBM diagnostic criteria. These criteria were applied through medical records review to 200 patients diagnosed as having IBM and 171 patients diagnosed as having a muscle disease other than IBM by neuromuscular specialists at 2 institutions, and to a validating set of 66 additional patients with IBM from 2 other institutions. Machine learning techniques were used for unbiased construction of diagnostic criteria. Results: Twenty-four previously proposed IBM diagnostic categories were identified. Twelve categories all performed with high (≥97%) specificity but varied substantially in their sensitivities (11%–84%). The best performing category was European Neuromuscular Centre 2013 probable (sensitivity of 84%). Specialized pathologic features and newly introduced strength criteria (comparative knee extension/hip flexion strength) performed poorly. Unbiased data-directed analysis of 20 features in 371 patients resulted in construction of higher-performing data-derived diagnostic criteria (90% sensitivity and 96% specificity). Conclusions: Published expert consensus–derived IBM diagnostic categories have uniformly high specificity but wide-ranging sensitivities. High-performing IBM diagnostic category criteria can be developed directly from principled unbiased analysis of patient data. Classification of evidence: This study provides Class II evidence that published expert consensus–derived IBM diagnostic categories accurately distinguish IBM from other muscle disease with high specificity but wide-ranging sensitivities. PMID:24975859

Extension of latin hypercube samples with correlated variables.

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

Hora, Stephen Curtis; Helton, Jon Craig; Sallaberry, Cedric J. PhD.

2006-11-01

A procedure for extending the size of a Latin hypercube sample (LHS) with rank correlated variables is described and illustrated. The extension procedure starts with an LHS of size m and associated rank correlation matrix C and constructs a new LHS of size 2m that contains the elements of the original LHS and has a rank correlation matrix that is close to the original rank correlation matrix C. The procedure is intended for use in conjunction with uncertainty and sensitivity analysis of computationally demanding models in which it is important to make efficient use of a necessarily limited number ofmore » model evaluations.« less

AOAC Official MethodSM Matrix Extension Validation Study of Assurance GDSTM for the Detection of Salmonella in Selected Spices.

PubMed

Feldsine, Philip; Kaur, Mandeep; Shah, Khyati; Immerman, Amy; Jucker, Markus; Lienau, Andrew

2015-01-01

Assurance GDSTM for Salmonella Tq has been validated according to the AOAC INTERNATIONAL Methods Committee Guidelines for Validation of Microbiological Methods for Food and Environmental Surfaces for the detection of selected foods and environmental surfaces (Official Method of AnalysisSM 2009.03, Performance Tested MethodSM No. 050602). The method also completed AFNOR validation (following the ISO 16140 standard) compared to the reference method EN ISO 6579. For AFNOR, GDS was given a scope covering all human food, animal feed stuff, and environmental surfaces (Certificate No. TRA02/12-01/09). Results showed that Assurance GDS for Salmonella (GDS) has high sensitivity and is equivalent to the reference culture methods for the detection of motile and non-motile Salmonella. As part of the aforementioned validations, inclusivity and exclusivity studies, stability, and ruggedness studies were also conducted. Assurance GDS has 100% inclusivity and exclusivity among the 100 Salmonella serovars and 35 non-Salmonella organisms analyzed. To add to the scope of the Assurance GDS for Salmonella method, a matrix extension study was conducted, following the AOAC guidelines, to validate the application of the method for selected spices, specifically curry powder, cumin powder, and chili powder, for the detection of Salmonella.

Motion analysis study on sensitivity of finite element model of the cervical spine to geometry.

PubMed

Zafarparandeh, Iman; Erbulut, Deniz U; Ozer, Ali F

2016-07-01

Numerous finite element models of the cervical spine have been proposed, with exact geometry or with symmetric approximation in the geometry. However, few researches have investigated the sensitivity of predicted motion responses to the geometry of the cervical spine. The goal of this study was to evaluate the effect of symmetric assumption on the predicted motion by finite element model of the cervical spine. We developed two finite element models of the cervical spine C2-C7. One model was based on the exact geometry of the cervical spine (asymmetric model), whereas the other was symmetric (symmetric model) about the mid-sagittal plane. The predicted range of motion of both models-main and coupled motions-was compared with published experimental data for all motion planes under a full range of loads. The maximum differences between the asymmetric model and symmetric model predictions for the principal motion were 31%, 78%, and 126% for flexion-extension, right-left lateral bending, and right-left axial rotation, respectively. For flexion-extension and lateral bending, the minimum difference was 0%, whereas it was 2% for axial rotation. The maximum coupled motions predicted by the symmetric model were 1.5° axial rotation and 3.6° lateral bending, under applied lateral bending and axial rotation, respectively. Those coupled motions predicted by the asymmetric model were 1.6° axial rotation and 4° lateral bending, under applied lateral bending and axial rotation, respectively. In general, the predicted motion response of the cervical spine by the symmetric model was in the acceptable range and nonlinearity of the moment-rotation curve for the cervical spine was properly predicted. © IMechE 2016.

Sensitivity analysis for parametric generalized implicit quasi-variational-like inclusions involving P-[eta]-accretive mappings

NASA Astrophysics Data System (ADS)

Kazmi, K. R.; Khan, F. A.

2008-01-01

In this paper, using proximal-point mapping technique of P-[eta]-accretive mapping and the property of the fixed-point set of set-valued contractive mappings, we study the behavior and sensitivity analysis of the solution set of a parametric generalized implicit quasi-variational-like inclusion involving P-[eta]-accretive mapping in real uniformly smooth Banach space. Further, under suitable conditions, we discuss the Lipschitz continuity of the solution set with respect to the parameter. The technique and results presented in this paper can be viewed as extension of the techniques and corresponding results given in [R.P. Agarwal, Y.-J. Cho, N.-J. Huang, Sensitivity analysis for strongly nonlinear quasi-variational inclusions, Appl. MathE Lett. 13 (2002) 19-24; S. Dafermos, Sensitivity analysis in variational inequalities, Math. Oper. Res. 13 (1988) 421-434; X.-P. Ding, Sensitivity analysis for generalized nonlinear implicit quasi-variational inclusions, Appl. Math. Lett. 17 (2) (2004) 225-235; X.-P. Ding, Parametric completely generalized mixed implicit quasi-variational inclusions involving h-maximal monotone mappings, J. Comput. Appl. Math. 182 (2) (2005) 252-269; X.-P. Ding, C.L. Luo, On parametric generalized quasi-variational inequalities, J. Optim. Theory Appl. 100 (1999) 195-205; Z. Liu, L. Debnath, S.M. Kang, J.S. Ume, Sensitivity analysis for parametric completely generalized nonlinear implicit quasi-variational inclusions, J. Math. Anal. Appl. 277 (1) (2003) 142-154; R.N. Mukherjee, H.L. Verma, Sensitivity analysis of generalized variational inequalities, J. Math. Anal. Appl. 167 (1992) 299-304; M.A. Noor, Sensitivity analysis framework for general quasi-variational inclusions, Comput. Math. Appl. 44 (2002) 1175-1181; M.A. Noor, Sensitivity analysis for quasivariational inclusions, J. Math. Anal. Appl. 236 (1999) 290-299; J.Y. Park, J.U. Jeong, Parametric generalized mixed variational inequalities, Appl. Math. Lett. 17 (2004) 43-48].

[Review on HSPF model for simulation of hydrology and water quality processes].

PubMed

Li, Zhao-fu; Liu, Hong-Yu; Li, Yan

2012-07-01

Hydrological Simulation Program-FORTRAN (HSPF), written in FORTRAN, is one ol the best semi-distributed hydrology and water quality models, which was first developed based on the Stanford Watershed Model. Many studies on HSPF model application were conducted. It can represent the contributions of sediment, nutrients, pesticides, conservatives and fecal coliforms from agricultural areas, continuously simulate water quantity and quality processes, as well as the effects of climate change and land use change on water quantity and quality. HSPF consists of three basic application components: PERLND (Pervious Land Segment) IMPLND (Impervious Land Segment), and RCHRES (free-flowing reach or mixed reservoirs). In general, HSPF has extensive application in the modeling of hydrology or water quality processes and the analysis of climate change and land use change. However, it has limited use in China. The main problems with HSPF include: (1) some algorithms and procedures still need to revise, (2) due to the high standard for input data, the accuracy of the model is limited by spatial and attribute data, (3) the model is only applicable for the simulation of well-mixed rivers, reservoirs and one-dimensional water bodies, it must be integrated with other models to solve more complex problems. At present, studies on HSPF model development are still undergoing, such as revision of model platform, extension of model function, method development for model calibration, and analysis of parameter sensitivity. With the accumulation of basic data and imorovement of data sharing, the HSPF model will be applied more extensively in China.

Multi-Targeted Agents in Cancer Cell Chemosensitization: What We Learnt from Curcumin Thus Far.

PubMed

Bordoloi, Devivasha; Roy, Nand K; Monisha, Javadi; Padmavathi, Ganesan; Kunnumakkara, Ajaikumar B

2016-01-01

Research over the past several years has developed many mono-targeted therapies for the prevention and treatment of cancer, but it still remains one of the fatal diseases in the world killing 8.2 million people annually. It has been well-established that development of chemoresistance in cancer cells against mono-targeted chemotherapeutic agents by modulation of multiple survival pathways is the major cause of failure of cancer chemotherapy. Therefore, inhibition of these pathways by non-toxic multi-targeted agents may have profoundly high potential in preventing drug resistance and sensitizing cancer cells to chemotherapeutic agents. To study the potential of curcumin, a multi-targeted natural compound, obtained from the plant Turmeric (Curcuma longa) in combination with standard chemotherapeutic agents to inhibit drug resistance and sensitize cancer cells to these agents based on available literature and patents. An extensive literature survey was performed in PubMed and Google for the chemosensitizing potential of curcumin in different cancers published so far and the patents published during 2014-2015. Our search resulted in many in vitro, in vivo and clinical reports signifying the chemosensitizing potential of curcumin in diverse cancers. There were 160 in vitro studies, 62 in vivo studies and 5 clinical studies. Moreover, 11 studies reported on hybrid curcumin: the next generation of curcumin based therapeutics. Also, 34 patents on curcumin's biological activity have been retrieved. Altogether, the present study reveals the enormous potential of curcumin, a natural, non-toxic, multi-targeted agent in overcoming drug resistance in cancer cells and sensitizing them to chemotherapeutic drugs.

Fluorescent hybridization probes for nucleic acid detection.

PubMed

Guo, Jia; Ju, Jingyue; Turro, Nicholas J

2012-04-01

Due to their high sensitivity and selectivity, minimum interference with living biological systems, and ease of design and synthesis, fluorescent hybridization probes have been widely used to detect nucleic acids both in vivo and in vitro. Molecular beacons (MBs) and binary probes (BPs) are two very important hybridization probes that are designed based on well-established photophysical principles. These probes have shown particular applicability in a variety of studies, such as mRNA tracking, single nucleotide polymorphism (SNP) detection, polymerase chain reaction (PCR) monitoring, and microorganism identification. Molecular beacons are hairpin oligonucleotide probes that present distinctive fluorescent signatures in the presence and absence of their target. Binary probes consist of two fluorescently labeled oligonucleotide strands that can hybridize to adjacent regions of their target and generate distinctive fluorescence signals. These probes have been extensively studied and modified for different applications by modulating their structures or using various combinations of fluorophores, excimer-forming molecules, and metal complexes. This review describes the applicability and advantages of various hybridization probes that utilize novel and creative design to enhance their target detection sensitivity and specificity.

Quantitative Mapping of the Spatial Distribution of Nanoparticles in Endo-Lysosomes by Local pH.

PubMed

Wang, Jing; MacEwan, Sarah R; Chilkoti, Ashutosh

2017-02-08

Understanding the intracellular distribution and trafficking of nanoparticle drug carriers is necessary to elucidate their mechanisms of drug delivery and is helpful in the rational design of novel nanoparticle drug delivery systems. The traditional immunofluorescence method to study intracellular distribution of nanoparticles using organelle-specific antibodies is laborious and subject to artifacts. As an alternative, we developed a new method that exploits ratiometric fluorescence imaging of a pH-sensitive Lysosensor dye to visualize and quantify the spatial distribution of nanoparticles in the endosomes and lysosomes of live cells. Using this method, we compared the endolysosomal distribution of cell-penetrating peptide (CPP)-functionalized micelles to unfunctionalized micelles and found that CPP-functionalized micelles exhibited faster endosome-to-lysosome trafficking than unfunctionalized micelles. Ratiometric fluorescence imaging of pH-sensitive Lysosensor dye allows rapid quantitative mapping of nanoparticle distribution in endolysosomes in live cells while minimizing artifacts caused by extensive sample manipulation typical of alternative approaches. This new method can thus serve as an alternative to traditional immunofluorescence approaches to study the intracellular distribution and trafficking of nanoparticles within endosomes and lysosomes.

Probing new charged scalars with neutrino trident production

NASA Astrophysics Data System (ADS)

Magill, Gabriel; Plestid, Ryan

2018-03-01

We investigate the possibility of using neutrino trident production to probe leptophilic charged scalars at future high intensity neutrino experiments. We show that under specific assumptions, this production process can provide competitive sensitivity for generic charged scalars as compared to common existing bounds. We also investigate how the recently proposed mixed-flavor production—where the two oppositely charged leptons in the final state need not be muon flavored—can give a 20%-50% increase in sensitivity for certain configurations of new physics couplings as compared to traditional trident modes. We then categorize all renormalizable leptophilic scalar extensions based on their representation under SU (2 )×U (1 ), and discuss the Higgs triplet and Zee-Babu models as explicit UV realizations. We find that the inclusion of additional doubly charged scalars and the need to reproduce neutrino masses make trident production uncompetitive with current bounds for these specific UV completions. Our work represents the first application of neutrino trident production to study charged scalars. Additionally, it is the first application of mixed-flavor trident production to study physics beyond the standard model more generally.

A proof of concept study to assess the potential of PCR testing to detect natural Mycobacterium bovis infection in South American camelids.

PubMed

Crawshaw, Timothy R; Chanter, Jeremy I; McGoldrick, Adrian; Line, Kirsty

2014-02-07

Cases of Mycobacterium bovis infection South American camelids have been increasing in Great Britain. Current antemortem immunological tests have some limitations. Cases at post mortem examination frequently show extensive pathology. The feasibility of detecting Mycobacterium bovis DNA in clinical samples was investigated. A sensitive extraction methodology was developed and used on nasal swabs and faeces taken post-mortem to assess the potential for a PCR test to detect Mycobacterium bovis in clinical samples. The gross pathology of the studied South American camelids was scored and a significantly greater proportion of South American camelids with more severe pathology were positive in both the nasal swab and faecal PCR tests. A combination of the nasal swab and faecal PCR tests detected 63.9% of all the South American camelids with pathology that were tested. The results suggest that antemortem diagnosis of Mycobacterium bovis in South American camelids may be possible using a PCR test on clinical samples, however more work is required to determine sensitivity and specificity, and the practicalities of applying the test in the field.

Development of Real Time PCR Using Novel Genomic Target for Detection of Multiple Salmonella Serovars from Milk and Chickens

USDA-ARS?s Scientific Manuscript database

Background: A highly sensitive and specific novel genomic and plasmid target-based PCR platform was developed to detect multiple Salmonella serovars (S. Heidelberg, S. Dublin, S. Hadar, S. Kentucky and S. Enteritidis). Through extensive genome mining of protein databases of these serovars and compar...

US 93 North post-construction wildlife-vehicle collision and wildlife crossing monitoring on the Flathead Indian reservation between Evaro and Polson, Montana : final report.

DOT National Transportation Integrated Search

2016-12-01

The US Highway 93 North reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to date in North America. The reconstruction of the 56 mile (90 km) ...

Evaluation of wildlife crossing structures and fencing on US Highway 93 Evaro to Polson Phase I : preconstruction data collection and finalization of evaluation plan : final report.

DOT National Transportation Integrated Search

2006-11-01

The US 93 reconstruction project on the Flathead Indian Reservation in northwest Montana represents one of the most extensive wildlife-sensitive highway design efforts to occur in the continental United States. The reconstruction will include install...

A minimalist biosensor: Quantitation of cyclic di-GMP using the conformational change of a riboswitch aptamer.

PubMed

Kellenberger, Colleen A; Sales-Lee, Jade; Pan, Yuchen; Gassaway, Madalee M; Herr, Amy E; Hammond, Ming C

2015-01-01

Cyclic di-GMP (c-di-GMP) is a second messenger that is important in regulating bacterial physiology and behavior, including motility and virulence. Many questions remain about the role and regulation of this signaling molecule, but current methods of detection are limited by either modest sensitivity or requirements for extensive sample purification. We have taken advantage of a natural, high affinity receptor of c-di-GMP, the Vc2 riboswitch aptamer, to develop a sensitive and rapid electrophoretic mobility shift assay (EMSA) for c-di-GMP quantitation that required minimal engineering of the RNA.

Sensitivity of the Lidar ratio to changes in size distribution and index of refraction

NASA Technical Reports Server (NTRS)

Evans, B. T. N.

1986-01-01

In order to invert lidar signals to obtain reliable extinction coefficients, sigma, a relationship between sigma and the backscatter coefficient, beta, must be given. These two coefficients are linearly related if the complex index of refraction, m, particle shape size distribution, N, does not change along the path illuminated by the laser beam. This, however, is generally not the case. An extensive Mie computation of the lidar ratio R = beta/sigma and the sensitivity of R to the changes in a parametric space defined by N and m were examined.

Short cavity DFB fiber laser based vector hydrophone for low frequency signal detection

NASA Astrophysics Data System (ADS)

Zhang, Xiaolei; Zhang, Faxiang; Jiang, Shaodong; Min, Li; Li, Ming; Peng, Gangding; Ni, Jiasheng; Wang, Chang

2017-12-01

A short cavity distributed feedback (DFB) fiber laser is used for low frequency acoustic signal detection. Three DFB fiber lasers with different central wavelengths are chained together to make three-element vector hydrophone with proper sensitivity enhancement design, which has extensive and significant applications to underwater acoustic monitoring for the national defense, oil, gas exploration, and so on. By wavelength-phase demodulation, the lasing wavelength changes under different frequency signals can be interpreted, and the sensitivity is tested about 33 dB re pm/g. The frequency response range is rather flat from 5 Hz to 300 Hz.

Sterile neutrino searches via displaced vertices at LHCb

NASA Astrophysics Data System (ADS)

Antusch, Stefan; Cazzato, Eros; Fischer, Oliver

2017-11-01

We explore the sensitivity of displaced vertex searches at LHCb for testing sterile neutrino extensions of the Standard Model towards explaining the observed neutrino masses. We derive estimates for the constraints on sterile neutrino parameters from a recently published displaced vertex search at LHCb based on run 1 data. They yield the currently most stringent limit on active-sterile neutrino mixing in the sterile neutrino mass range between 4.5 GeV and 10 GeV. Furthermore, we present forecasts for the sensitivities that could be obtained from the run 2 data and also for the high-luminosity phase of the LHC.

Fiber Bragg grating cryogenic temperature sensors

NASA Astrophysics Data System (ADS)

Gupta, Sanjay; Mizunami, Toru; Yamao, Takashi; Shimomura, Teruo

1996-09-01

Temperature sensing to as low as 80 K was demonstrated with 1.55- mu m fiber Bragg gratings. The gratings were bonded on substrates to increase sensitivity, and a shift of the reflection wavelength was measured. The temperature sensitivity was 0.02 nm/K at 100 K when an aluminum substrate was used and 0.04 nm/K at 100 K when a poly(methyl methacrylate) substrate was used. These values are smaller than those at room temperature because of the nonlinearity of both the thermal expansion and the thermo-optic effect. Extension to the liquid helium temperature is also discussed.

Program Helps To Determine Chemical-Reaction Mechanisms

NASA Technical Reports Server (NTRS)

Bittker, D. A.; Radhakrishnan, K.

1995-01-01

General Chemical Kinetics and Sensitivity Analysis (LSENS) computer code developed for use in solving complex, homogeneous, gas-phase, chemical-kinetics problems. Provides for efficient and accurate chemical-kinetics computations and provides for sensitivity analysis for variety of problems, including problems involving honisothermal conditions. Incorporates mathematical models for static system, steady one-dimensional inviscid flow, reaction behind incident shock wave (with boundary-layer correction), and perfectly stirred reactor. Computations of equilibrium properties performed for following assigned states: enthalpy and pressure, temperature and pressure, internal energy and volume, and temperature and volume. Written in FORTRAN 77 with exception of NAMELIST extensions used for input.

IdentiPy: An Extensible Search Engine for Protein Identification in Shotgun Proteomics.

PubMed

Levitsky, Lev I; Ivanov, Mark V; Lobas, Anna A; Bubis, Julia A; Tarasova, Irina A; Solovyeva, Elizaveta M; Pridatchenko, Marina L; Gorshkov, Mikhail V

2018-06-18

We present an open-source, extensible search engine for shotgun proteomics. Implemented in Python programming language, IdentiPy shows competitive processing speed and sensitivity compared with the state-of-the-art search engines. It is equipped with a user-friendly web interface, IdentiPy Server, enabling the use of a single server installation accessed from multiple workstations. Using a simplified version of X!Tandem scoring algorithm and its novel "autotune" feature, IdentiPy outperforms the popular alternatives on high-resolution data sets. Autotune adjusts the search parameters for the particular data set, resulting in improved search efficiency and simplifying the user experience. IdentiPy with the autotune feature shows higher sensitivity compared with the evaluated search engines. IdentiPy Server has built-in postprocessing and protein inference procedures and provides graphic visualization of the statistical properties of the data set and the search results. It is open-source and can be freely extended to use third-party scoring functions or processing algorithms and allows customization of the search workflow for specialized applications.

Contrast-enhanced [18F] fluorodeoxyglucose-positron emission tomography-computed tomography as an initial imaging modality in patients presenting with metastatic malignancy of undefined primary origin

PubMed Central

Jain, Avani; Srivastava, Madhur Kumar; Pawaskar, Alok Suresh; Shelley, Simon; Elangovan, Indirani; Jain, Hasmukh; Pandey, Somnath; Kalal, Shilpa; Amalachandran, Jaykanth

2015-01-01

Background: To evaluate the advantages of contrast enhanced F-18-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-contrast enhanced CT [CECT]) when used as an initial imaging modality in patients presenting with metastatic malignancy of undefined primary origin (MUO). Materials and Methods: A total of 243 patients with fine needle aspiration cytology/biopsy proven MUO were included in this prospective study. Patients who were thoroughly evaluated for primary or primary tumor was detected by any other investigation were excluded from the analysis. Totally, 163 patients with pathological diagnosis of malignancy but no apparent sites of the primary tumor were finally selected for analysis. The site of probable primary malignancy suggested by PET-CECT was confirmed by biopsy/follow-up. Results: PET-CECT suggested probable site of primary in 128/163 (78.52%) patients. In 30/35 remaining patients, primary tumor was not detected even after extensive work-up. In 5 patients, where PET-CECT was negative, primary was found on further extensive investigations or follow-up. The sensitivity, specificity, positive predictive value and negative predictive value of the study were 95.76%, 66.67%, 88.28% and 85.71% respectively. Conclusions: F-18 FDG PET-CECT aptly serves the purpose of initial imaging modality owing to high sensitivity, negative and positive predictive value. PET-CECT not only surveys the whole body for the primary malignancy but also stages the disease accurately. Use of contrast improves the diagnostic utility of modality as well as help in staging of the primary tumor. Although benefits of using PET-CECT as initial diagnostic modality are obvious from this study, there is a need for a larger study comparing conventional methods for diagnosing primary in patients with MUO versus PET-CECT. PMID:26170563

A Wirelessly Powered Smart Contact Lens with Reconfigurable Wide Range and Tunable Sensitivity Sensor Readout Circuitry

PubMed Central

Chiou, Jin-Chern; Hsu, Shun-Hsi; Huang, Yu-Chieh; Yeh, Guan-Ting; Liou, Wei-Ting; Kuei, Cheng-Kai

2017-01-01

This study presented a wireless smart contact lens system that was composed of a reconfigurable capacitive sensor interface circuitry and wirelessly powered radio-frequency identification (RFID) addressable system for sensor control and data communication. In order to improve compliance and reduce user discomfort, a capacitive sensor was embedded on a soft contact lens of 200 μm thickness using commercially available bio-compatible lens material and a standard manufacturing process. The results indicated that the reconfigurable sensor interface achieved sensitivity and baseline tuning up to 120 pF while consuming only 110 μW power. The range and sensitivity tuning of the readout circuitry ensured a reliable operation with respect to sensor fabrication variations and independent calibration of the sensor baseline for individuals. The on-chip voltage scaling allowed the further extension of the detection range and prevented the implementation of large on-chip elements. The on-lens system enabled the detection of capacitive variation caused by pressure changes in the range of 2.25 to 30 mmHg and hydration level variation from a distance of 1 cm using incident power from an RFID reader at 26.5 dBm. PMID:28067859

How Business Cycles Affect the Healthcare Sector: A Cross-country Investigation.

PubMed

Cleeren, Kathleen; Lamey, Lien; Meyer, Jan-Hinrich; De Ruyter, Ko

2016-07-01

The long-term relationship between the general economy and healthcare expenditures has been extensively researched, to explain differences in healthcare spending between countries, but the midterm (i.e., business cycle) perspective has been overlooked. This study explores business cycle sensitivity in both public and private parts of the healthcare sector across 32 countries. Responses to the business cycle vary notably, both across spending sources and across countries. Whereas in some countries, consumers and/or governments cut back, in others, private and/or public healthcare buyers tend to spend more. We also assess long-term consequences of business cycle sensitivity and show that public cost cutting during economic downturns deflates the mortality rates, whereas private cut backs increase the long-term growth in total healthcare expenditures. Finally, multiple factors help explain variability in cyclical sensitivity. Private cost cuts during economic downturns are smaller in countries with a predominantly publicly funded healthcare system and more preventive public activities. Public cut backs during contractions are smaller in countries that rely more on tax-based resources rather than social health insurances. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Diagnosis of uterine cervix cancer using Müller polarimetry: a comparison with histopathology

NASA Astrophysics Data System (ADS)

Rehbinder, Jean; Deby, Stanislas; Haddad, Huda; Teig, Benjamin; Nazac, André; Pierangelo, Angelo; Moreau, François

2015-07-01

Today around 275000 women a year in the world keep dying from the cancer of uterine cervix due to the difficulty to meet the logistic requirements of an organized screening in the developing world. Polarimetric imaging is a new promising technique with a tremendous potential for applications in biomedical diagnostics: it is sensitive to slight morphological changes in tissues, can provide wide field images for the screening and requires light sources such as a LED for example. This work intends to characterize the polarimetric response of the uterine cervix in its healthy and pathological states. An extensive series of ex-vivo measurements is in progress the Kremlin Bicêtre hospital near Paris using an imaging multispectral Mueller polarimeter in backscattering configuration. The goal of this study is to evaluate the performances of polarimetric imaging technique in terms of sensitivity and specificity for the detection of healthy epithelia (Healthy Squamous epithelium and Malpighian Metaplasia) with respect to the diagnosis provided by pathologists from histology slides as the "gold standard". We show that, at λ=550nm, performances as high as 62% sensitivity and 64% specificity are achieved by optimizing a simple threshold on the scalar retardance values.

Macular Sensitivity Measured With Microperimetry in Stargardt Disease in the Progression of Atrophy Secondary to Stargardt Disease (ProgStar) Study: Report No. 7.

PubMed

Schönbach, Etienne M; Wolfson, Yulia; Strauss, Rupert W; Ibrahim, Mohamed A; Kong, Xiangrong; Muñoz, Beatriz; Birch, David G; Cideciyan, Artur V; Hahn, Gesa-Astrid; Nittala, Muneeswar; Sunness, Janet S; Sadda, SriniVas R; West, Sheila K; Scholl, Hendrik P N

2017-07-01

New outcome measures for treatment trials for Stargardt disease type 1 (STGD1) and other macular diseases are needed. Microperimetry allows mapping of light sensitivity of the macula and provides topographic information on visual function beyond visual acuity. To measure and analyze retinal light sensitivity of the macula in STGD1 using fundus-controlled perimetry (microperimetry). This was a multicenter prospective cohort study. A total of 199 patients and 326 eyes with molecularly confirmed (ABCA4) STGD1 underwent testing with the Nidek MP-1 microperimeter as part of the multicenter, prospective Natural History of the Progression of Atrophy Secondary to Stargardt Disease (ProgStar) study. Sensitivity of 68 retinal loci was tested, and the mean sensitivity (MS) was determined; each point was categorized as "normal," "relative," or "deep" scotoma. Mean sensitivity and the number of points with normal sensitivity, relative, or deep scotomas. Mean (SD) patient age was 34.2 (14.7) years, mean (SD) best-corrected visual acuity of all eyes was 47.8 (16.9) Early Treatment Diabetic Retinopathy Study letter score (approximately 20/100 Snellen equivalent), and mean MS of all eyes of all 68 points was 11.0 (5.0) dB. The median number of normal points per eye was 49 (mean [SD], 41.3 [20.8]; range, 0-68); abnormal sensitivity and deep scotomas were more prevalent in the central macula. Mean sensitivity was lower in the fovea (mean [SD], 2.7 [4.4] dB) than in the inner (mean [SD], 6.8 [5.8] dB) and outer ring (mean [SD], 12.7 [5.3] dB). Overall MS per eye was 0.086 dB lower per year of additional age (95% CI, -0.13 to -0.041; P < .001) and 0.21 dB lower per additional year of duration of STGD1 (95% CI, -0.28 to -0.14; P < .001). Longer duration of STGD1 was associated with worse MS (β = -0.18; P < .001), with a lower number of normal test points (β = -0.71; P < .001), and with a higher number of deep scotoma points (β = -0.70; P < .001). We found 11 eyes with low MS (<6 dB) but very good best-corrected visual acuity of at least 72 Early Treatment Diabetic Retinopathy Study letter score (20/40 Snellen equivalent). We provide an extensive analysis of macular sensitivity parameters in STGD1 and demonstrate their association with demographic characteristics and vision. These data suggest microperimetry testing provides a more comprehensive assessment of retinal function and will be an important outcome measure in future clinical trials.

Wound infection secondary to snakebite.

PubMed

Wagener, M; Naidoo, M; Aldous, C

2017-03-29

Snakebites can produce severe local and systemic septic complications as well as being associated with significant overall morbidity and even mortality. A prospective audit was undertaken to determine the bacterial causation of wound infection secondary to snakebite, and attempt to quantify the burden of disease. The audit was undertaken at Ngwelezane Hospital, which provides both regional and tertiary services for north-eastern KwaZulu-Natal Province, South Africa, over a 4-month period. Records of patients who required surgical debridement for extensive skin and soft-tissue necrosis were analysed. At the time of debridement, tissue samples of necrotic or infected tissue were sent for bacteriological analysis as standard of care. Microbiology results were analysed. A total of 164 patients were admitted to hospital for management of snakebite, of whom 57 required surgical debridement and 42 were included in the final microbiological analysis. Children were found to be the most frequent victims of snakebite; 57.8% of patients in this study were aged ≤10 years and 73.7% ≤15 years. Culture showed a single organism in 32/42 cases, two organisms in 8 and no growth in 2. Eight different types of organisms were cultured, five of them more than once. Thirty-five specimens (83.3%) grew Gram-negative Enterobacteriaceae, the most frequent being Morganella morganii and Proteus species. Thirteen specimens (31.0%) grew Enterococcus faecalis. Gram-negative Enterobacteriaceae showed 31.4% sensitivity to ampicillin, 40.0% sensitivity to amoxicillin plus clavulanic acid, 34.3% sensitivity to cefuroxime, 97.1% sensitivity to ceftriaxone, and 100% sensitivity to ciprofloxacin, gentamicin and amikacin. E. faecalis was 92.3% sensitive to amoxicillin, 92.3% sensitive to amoxicillin plus clavulanic acid, 100% sensitive to ciprofloxacin, 92.3% resistant to erythromycin and 100% resistant to ceftriaxone. Children are particularly vulnerable to snakebite, and the consequences can be devastating. While the majority of patients in this study were shown to have secondary bacterial infection, debridement and subsequent wound management is considered the mainstay of treatment. Common organisms are Enterobacteriaceae and enterococci. There appears to be a role for antibiotics in the management of these patients. A good antibiotic policy is strongly advocated.

Genetic Variation in Taste Sensitivity to Sugars in Drosophila melanogaster.

PubMed

Uchizono, Shun; Tanimura, Teiichi

2017-05-01

Taste sensitivity plays a major role in controlling feeding behavior, and alterations in feeding habit induced by changes in taste sensitivity can drive speciation. We investigated variability in taste preferences in wild-derived inbred lines from the Drosophila melanogaster Genetic Reference Panel. Preferences for different sugars, which are essential nutrients for fruit flies, were assessed using two-choice preference tests that paired glucose with fructose, sucrose, or trehalose. The two-choice tests revealed that individual lines have differential and widely variable sugar preferences, and that sugar taste sensitivity is polygenic in the inbred population tested. We focused on 2 strains that exhibited opposing preferences for glucose and fructose, and performed proboscis extension reflex tests and electrophysiological recordings on taste sensilla upon exposure to fructose and glucose. The results indicated that taste sensitivity to fructose is dimorphic between the 2 lines. Genetic analysis showed that high sensitivity to fructose is autosomal dominant over low sensitivity, and that multiple loci on chromosomes 2 and 3 influence sensitivity. Further genetic complementation tests for fructose sensitivity on putative gustatory receptor (Gr) genes for sugars suggested that the Gr64a-Gr64f locus, not the fructose receptor gene Gr43a, might contribute to the dimorphic sensitivity to fructose between the 2 lines. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A New Method to Measure Crack Extension in Nuclear Graphite Based on Digital Image Correlation

DOE PAGES

Lai, Shigang; Shi, Li; Fok, Alex; ...

2017-01-01

Graphite components, used as moderators, reflectors, and core-support structures in a High-Temperature Gas-Cooled Reactor, play an important role in the safety of the reactor. Specifically, they provide channels for the fuel elements, control rods, and coolant flow. Fracture is the main failure mode for graphite, and breaching of the above channels by crack extension will seriously threaten the safety of a reactor. In this paper, a new method based on digital image correlation (DIC) is introduced for measuring crack extension in brittle materials. Cross-correlation of the displacements measured by DIC with a step function was employed to identify the advancingmore » crack tip in a graphite beam specimen under three-point bending. The load-crack extension curve, which is required for analyzing the R-curve and tension softening behaviors, was obtained for this material. Furthermore, a sensitivity analysis of the threshold value employed for the cross-correlation parameter in the crack identification process was conducted. Finally, the results were verified using the finite element method.« less

A New Method to Measure Crack Extension in Nuclear Graphite Based on Digital Image Correlation

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

Lai, Shigang; Shi, Li; Fok, Alex

Graphite components, used as moderators, reflectors, and core-support structures in a High-Temperature Gas-Cooled Reactor, play an important role in the safety of the reactor. Specifically, they provide channels for the fuel elements, control rods, and coolant flow. Fracture is the main failure mode for graphite, and breaching of the above channels by crack extension will seriously threaten the safety of a reactor. In this paper, a new method based on digital image correlation (DIC) is introduced for measuring crack extension in brittle materials. Cross-correlation of the displacements measured by DIC with a step function was employed to identify the advancingmore » crack tip in a graphite beam specimen under three-point bending. The load-crack extension curve, which is required for analyzing the R-curve and tension softening behaviors, was obtained for this material. Furthermore, a sensitivity analysis of the threshold value employed for the cross-correlation parameter in the crack identification process was conducted. Finally, the results were verified using the finite element method.« less

Extensively Drug-Resistant Tuberculosis: Principles of Resistance, Diagnosis, and Management.

PubMed

Wilson, John W; Tsukayama, Dean T

2016-04-01

Extensively drug-resistant (XDR) tuberculosis (TB) is an unfortunate by-product of mankind's medical and pharmaceutical ingenuity during the past 60 years. Although new drug developments have enabled TB to be more readily curable, inappropriate TB management has led to the emergence of drug-resistant disease. Extensively drug-resistant TB describes Mycobacterium tuberculosis that is collectively resistant to isoniazid, rifampin, a fluoroquinolone, and an injectable agent. It proliferates when established case management and infection control procedures are not followed. Optimized treatment outcomes necessitate time-sensitive diagnoses, along with expanded combinations and prolonged durations of antimicrobial drug therapy. The challenges to public health institutions are immense and most noteworthy in underresourced communities and in patients coinfected with human immunodeficiency virus. A comprehensive and multidisciplinary case management approach is required to optimize outcomes. We review the principles of TB drug resistance and the risk factors, diagnosis, and managerial approaches for extensively drug-resistant TB. Treatment outcomes, cost, and unresolved medical issues are also discussed. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Numerical simulation of geomorphic, climatic and anthropogenic drivers of soil distribution on semi-arid hillslopes

NASA Astrophysics Data System (ADS)

Willgoose, G. R.; Cohen, S.; Svoray, T.; Sela, S.; Hancock, G. R.

2010-12-01

Numerical models are an important tool for studying landscape processes as they allow us to isolate specific processes and drivers and test various physics and spatio-temporal scenarios. Here we use a distributed physically-based soil evolution model (mARM4D) to describe the drivers and processes controlling soil-landscape evolution on a field-site at the fringe between the Mediterranean and desert regions of Israel. This study is an initial effort in a larger project aimed at improving our understanding of the mechanisms and drivers that led to the extensive removal of soils from the loess covered hillslopes of this region. This specific region is interesting as it is located between the Mediterranean climate region in which widespread erosion from hillslopes was attributed to human activity during the Holocene and the arid region in which extensive removal of loess from hillslopes was shown to have been driven by climatic changes during the late-Pleistocene. First we study the sediment transport mechanism of the soil-landscape evolution processes in our study-site. We simulate soil-landscape evolution with only one sediment transport process (fluvial or diffusive) at a time. We find that diffusive sediment transport is likely the dominant process in this site as it resulted in soil distributions that better corresponds to current observations. We then simulate several realistic climatic/anthropogenic scenarios (based on the literature) in order to quantify the sensitivity of the soil-landscape evolution process to temporal fluctuations. We find that this site is relatively insensitive to short term (several thousands of years) sharp, changes. This suggests that climate, rather then human activity, was the main driver for the extensive removal of loess from the hillslopes.

Search for Indirect Signals of Dark Matter with The High Altitude Water Cherenkov (HAWC) Observatory

NASA Astrophysics Data System (ADS)

Baughman, Brian; Harding, Patrick; HAWC Collaboration

2015-04-01

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view observatory sensitive to 100 GeV-100 TeV gamma rays and cosmic rays. Located at an elevation of 4100 m on the Sierra Negra volcano in Mexico, HAWC observes extensive air showers from gamma rays via their production of Cherenkov light within an array of water tanks. With a wide field-of-view observing 2/3 of the sky each day and a sensitivity of greater than 1 Crab per day, HAWC has the ability to probe a large fraction of the sky for the signals of TeV-mass dark matter. HAWC's sensitivity to dark matter for several astrophysical sources and some early limits from the built detector will be presented.

Self-rating inventory for posttraumatic stress disorder: review of the psychometric properties of a new brief Dutch screening instrument.

PubMed

Hovens, J E; Bramsen, I; van der Ploeg, H M

2002-06-01

The Self-rating Inventory for Posttraumatic Stress Disorder of 22 items was developed for use with populations without identified traumatic experiences. The inventory has been used extensively in survey research in The Netherlands. This paper examines the psychometric properties. In four different groups (trauma and psychiatric patients, elderly Dutch subjects, former peacekeepers, and medical students) internal consistency, test-retest reliability, concurrent and discriminant validity, and sensitivity and specificity are analyzed. The inventory showed good internal consistency, test-retest reliability, concurrent and discriminant validity, and high sensitivity and specificity. It appears to be valuable for survey research on posttraumatic stress in nonselected populations. As a screening device, high sensitivity for PTSD symptoms is evident even when the traumatic event has not been defined.

Temperature Sensitive Singlet Oxygen Photosensitization by LOV-Derived Fluorescent Flavoproteins.

PubMed

Westberg, Michael; Bregnhøj, Mikkel; Etzerodt, Michael; Ogilby, Peter R

2017-03-30

Optogenetic sensitizers that selectively produce a given reactive oxygen species (ROS) constitute a promising tool for studying cell signaling processes with high levels of spatiotemporal control. However, to harness the full potential of this tool for live cell studies, the photophysics of currently available systems need to be explored further and optimized. Of particular interest in this regard, are the flavoproteins miniSOG and SOPP, both of which (1) contain the chromophore flavin mononucleotide, FMN, in a LOV-derived protein enclosure, and (2) photosensitize the production of singlet oxygen, O 2 (a 1 Δ g ). Here we present an extensive experimental study of the singlet and triplet state photophysics of FMN in SOPP and miniSOG over a physiologically relevant temperature range. Although changes in temperature only affect the singlet excited state photophysics slightly, the processes that influence the deactivation of the triplet excited state are more sensitive to temperature. Most notably, for both proteins, the rate constant for quenching of 3 FMN by ground state oxygen, O 2 (X 3 Σ g - ), increases ∼10-fold upon increasing the temperature from 10 to 43 °C, while the oxygen-independent channels of triplet state deactivation are less affected. As a consequence, this increase in temperature results in higher yields of O 2 (a 1 Δ g ) formation for both SOPP and miniSOG. We also show that the quantum yields of O 2 (a 1 Δ g ) production by both miniSOG and SOPP are mainly limited by the fraction of FMN triplet states quenched by O 2 (X 3 Σ g - ). The results presented herein provide a much-needed quantitative framework that will facilitate the future development of optogenetic ROS sensitizers.

Reservoir Performance Under Future Climate For Basins With Different Hydrologic Sensitivities

NASA Astrophysics Data System (ADS)

Mateus, M. C.; Tullos, D. D.

2013-12-01

In addition to long-standing uncertainties related to variable inflows and market price of power, reservoir operators face a number of new uncertainties related to hydrologic nonstationarity, changing environmental regulations, and rapidly growing water and energy demands. This study investigates the impact, sensitivity, and uncertainty of changing hydrology on hydrosystem performance across different hydrogeologic settings. We evaluate the performance of reservoirs in the Santiam River basin, including a case study in the North Santiam Basin, with high permeability and extensive groundwater storage, and the South Santiam Basin, with low permeability, little groundwater storage and rapid runoff response. The modeling objective is to address the following study questions: (1) for the two hydrologic regimes, how does the flood management, water supply, and environmental performance of current reservoir operations change under future 2.5, 50 and 97.5 percentile streamflow projections; and (2) how much change in inflow is required to initiate a failure to meet downstream minimum or maximum flows in the future. We couple global climate model results with a rainfall-runoff model and a formal Bayesian uncertainty analysis to simulate future inflow hydrographs as inputs to a reservoir operations model. To evaluate reservoir performance under a changing climate, we calculate reservoir refill reliability, changes in flood frequency, and reservoir time and volumetric reliability of meeting minimum spring and summer flow target. Reservoir performance under future hydrology appears to vary with hydrogeology. We find higher sensitivity to floods for the North Santiam Basin and higher sensitivity to minimum flow targets for the South Santiam Basin. Higher uncertainty is related with basins with a more complex hydrologeology. Results from model simulations contribute to understanding of the reliability and vulnerability of reservoirs to a changing climate.

Frequent biphasic cellular responses of permanent fish cell cultures to deoxynivalenol (DON)

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

Pietsch, Constanze, E-mail: constanze.pietsch@unibas.ch; Bucheli, Thomas D.; Wettstein, Felix E.

Contamination of animal feed with mycotoxins is a major problem for fish feed mainly due to usage of contaminated ingredients for production and inappropriate storage of feed. The use of cereals for fish food production further increases the risk of a potential contamination. Potential contaminants include the mycotoxin deoxynivalenol (DON) which is synthesized by globally distributed fungi of the genus Fusarium. The toxicity of DON is well recognized in mammals. In this study, we confirm cytotoxic effects of DON in established permanent fish cell lines. We demonstrate that DON is capable of influencing the metabolic activity and cell viability inmore » fish cells as determined by different assays to indicate possible cellular targets of this toxin. Evaluation of cell viability by measurement of membrane integrity, mitochondrial activity and lysosomal function after 24 h of exposure of fish cell lines to DON at a concentration range of 0-3000 ng ml{sup -1} shows a biphasic effect on cells although differences in sensitivity occur. The cell lines derived from rainbow trout are particularly sensitive to DON. The focus of this study lies, furthermore, on the effects of DON at different concentrations on production of reactive oxygen species (ROS) in the different fish cell lines. The results show that DON mainly reduces ROS production in all cell lines that were used. Thus, our comparative investigations reveal that the fish cell lines show distinct species-related endpoint sensitivities that also depend on the type of tissue from which the cells were derived and the severity of exposure. - Highlights: > DON uptake by cells is not extensive. > All fish cell lines are sensitive to DON. > DON is most cytotoxic to rainbow trout cells. > Biphasic cellular responses were frequently observed. > Our results are similar to studies on mammalian cell lines.« less

Running as Interoceptive Exposure for Decreasing Anxiety Sensitivity: Replication and Extension.

PubMed

Sabourin, Brigitte C; Stewart, Sherry H; Watt, Margo C; Krigolson, Olav E

2015-01-01

A brief, group cognitive behavioural therapy with running as the interoceptive exposure (IE; exposure to physiological sensations) component was effective in decreasing anxiety sensitivity (AS; fear of arousal sensations) levels in female undergraduates (Watt et al., Anxiety and Substance Use Disorders: The Vicious Cycle of Comorbidity, 201-219, 2008). Additionally, repeated exposure to running resulted in decreases in cognitive (i.e., catastrophic thoughts) and affective (i.e., feelings of anxiety) reactions to running over time for high AS, but not low AS, participants (Sabourin et al., "Physical exercise as interoceptive exposure within a brief cognitive-behavioral treatment for anxiety-sensitive women", Journal of Cognitive Psychotherapy, 22:302-320, 2008). A follow-up study including the above-mentioned intervention with an expanded IE component also resulted in decreases in AS levels (Sabourin et al., under review). The goals of the present process study were (1) to replicate the original process study, with the expanded IE component, and (2) to determine whether decreases in cognitive, affective, and/or somatic (physiological sensations) reactions to running would be related to decreases in AS. Eighteen high AS and 10 low AS participants completed 20 IE running trials following the 3-day group intervention. As predicted, high AS participants, but not low AS participants, experienced decreases in cognitive, affective, and somatic reactions to running over time. Furthermore, decreases in cognitive and affective, but not in somatic, reactions to running were related to decreases in AS levels. These results suggest that the therapeutic effects of repeated exposure to running in decreasing sensitivity to anxiety-related sensations are not related to decreasing the experience of somatic sensations themselves. Rather, they are related to altering the cognitive and affective reactions to these sensations.

Modelling ecological and human exposure to POPs in Venice lagoon - Part II: Quantitative uncertainty and sensitivity analysis in coupled exposure models.

PubMed

Radomyski, Artur; Giubilato, Elisa; Ciffroy, Philippe; Critto, Andrea; Brochot, Céline; Marcomini, Antonio

2016-11-01

The study is focused on applying uncertainty and sensitivity analysis to support the application and evaluation of large exposure models where a significant number of parameters and complex exposure scenarios might be involved. The recently developed MERLIN-Expo exposure modelling tool was applied to probabilistically assess the ecological and human exposure to PCB 126 and 2,3,7,8-TCDD in the Venice lagoon (Italy). The 'Phytoplankton', 'Aquatic Invertebrate', 'Fish', 'Human intake' and PBPK models available in MERLIN-Expo library were integrated to create a specific food web to dynamically simulate bioaccumulation in various aquatic species and in the human body over individual lifetimes from 1932 until 1998. MERLIN-Expo is a high tier exposure modelling tool allowing propagation of uncertainty on the model predictions through Monte Carlo simulation. Uncertainty in model output can be further apportioned between parameters by applying built-in sensitivity analysis tools. In this study, uncertainty has been extensively addressed in the distribution functions to describe the data input and the effect on model results by applying sensitivity analysis techniques (screening Morris method, regression analysis, and variance-based method EFAST). In the exposure scenario developed for the Lagoon of Venice, the concentrations of 2,3,7,8-TCDD and PCB 126 in human blood turned out to be mainly influenced by a combination of parameters (half-lives of the chemicals, body weight variability, lipid fraction, food assimilation efficiency), physiological processes (uptake/elimination rates), environmental exposure concentrations (sediment, water, food) and eating behaviours (amount of food eaten). In conclusion, this case study demonstrated feasibility of MERLIN-Expo to be successfully employed in integrated, high tier exposure assessment. Copyright © 2016 Elsevier B.V. All rights reserved.

Correlation between Preoperative High Resolution Computed Tomography (CT) Findings with Surgical Findings in Chronic Otitis Media (COM) Squamosal Type.

PubMed

Karki, S; Pokharel, M; Suwal, S; Poudel, R

Background The exact role of High resolution computed tomography (HRCT) temporal bone in preoperative assessment of Chronic suppurative otitis media atticoantral disease still remains controversial. Objective To evaluate the role of high resolution computed tomography temporal bone in Chronic suppurative otitis media atticoantral disease and to compare preoperative computed tomographic findings with intra-operative findings. Method Prospective, analytical study conducted among 65 patients with chronic suppurative otitis media atticoantral disease in Department of Radiodiagnosis, Kathmandu University Dhulikhel Hospital between January 2015 to July 2016. The operative findings were compared with results of imaging. The parameters of comparison were erosion of ossicles, scutum, facial canal, lateral semicircular canal, sigmoid and tegmen plate along with extension of disease to sinus tympani and facial recess. Sensitivity, specificity, negative predictive value, positive predictive values were calculated. Result High resolution computed tomography temporal bone offered sensitivity (Se) and specificity (Sp) of 100% for visualization of sigmoid and tegmen plate erosion. The performance of HRCT in detecting malleus (Se=100%, Sp=95.23%), incus (Se=100%,Sp=80.48%) and stapes (Se=96.55%, Sp=71.42%) erosion was excellent. It offered precise information about facial canal erosion (Se=100%, Sp=75%), scutum erosion (Se=100%, Sp=96.87%) and extension of disease to facial recess and sinus tympani (Se=83.33%,Sp=100%). high resolution computed tomography showed specificity of 100% for lateral semicircular canal erosion (Sp=100%) but with low sensitivity (Se=53.84%). Conclusion The findings of high resolution computed tomography and intra-operative findings were well comparable except for lateral semicircular canal erosion. high resolution computed tomography temporal bone acts as a road map for surgeon to identify the extent of disease, plan for appropriate procedure that is required and prepare for potential complications that can be encountered during surgery.

[Diagnostic strategies in the Tuberculosis Clinic of the Hospital General La Raza National Medical Center].

PubMed

Flores-Ibarra, Alberto Alejandro; Ochoa-Vázquez, María Dolores; Sánchez-Tec, Georgina Alejandra

2016-01-01

In order to diagnose TB infection, tuberculin skin test and interferon gamma release assay are available. The tuberculin test has a sensitivity of 99 % and a specificity of 95 %. For the detection of interferon gamma in blood there are currently two tests available: TBGold QuantiFERON-In-Tube (with a sensitivity of 0.70 and a specificity of 0.90), and T-SPOT-TB (sensitivity 0.90 and specificity 0.93). To diagnose the disease, a microscopy of direct smears for acid-fast bacilli is used if the physician is facing an extensive cavitary lung disease due to M. tuberculosis (this test has a high sensitivity: 80-90 %). The most common staining techniques used are Ziehl-Neelsen and Kinyoun, and the fluorescent technique, auramine-rhodamine. The culture is the gold standard and it has a sensitivity of 80 % and a specificity over 90 %, but the results take weeks. The nucleic acid amplification test has an overall sensitivity and specificity of 0.85 and 0.97, respectively. In the presence of a pleural effusion is necessary to perform a pleural biopsy for culture with a sensitivity of 85 % if it is percutaneous and 98 % if it was taken by thoracoscopy. The adenosine deaminase can be determined in pleural fluid with a sensitivity and specificity of 95 %.

Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity

PubMed Central

Elli, Luca; Branchi, Federica; Tomba, Carolina; Villalta, Danilo; Norsa, Lorenzo; Ferretti, Francesca; Roncoroni, Leda; Bardella, Maria Teresa

2015-01-01

Cereal crops and cereal consumption have had a vital role in Mankind’s history. In the recent years gluten ingestion has been linked with a range of clinical disorders. Gluten-related disorders have gradually emerged as an epidemiologically relevant phenomenon with an estimated global prevalence around 5%. Celiac disease, wheat allergy and non-celiac gluten sensitivity represent different gluten-related disorders. Similar clinical manifestations can be observed in these disorders, yet there are peculiar pathogenetic pathways involved in their development. Celiac disease and wheat allergy have been extensively studied, while non-celiac gluten sensitivity is a relatively novel clinical entity, believed to be closely related to other gastrointestinal functional syndromes. The diagnosis of celiac disease and wheat allergy is based on a combination of findings from the patient’s clinical history and specific tests, including serology and duodenal biopsies in case of celiac disease, or laboratory and functional assays for wheat allergy. On the other hand, non-celiac gluten sensitivity is still mainly a diagnosis of exclusion, in the absence of clear-cut diagnostic criteria. A multimodal pragmatic approach combining findings from the clinical history, symptoms, serological and histological tests is required in order to reach an accurate diagnosis. A thorough knowledge of the differences and overlap in clinical presentation among gluten-related disorders, and between them and other gastrointestinal disorders, will help clinicians in the process of differential diagnosis. PMID:26109797

Diagnosis of gluten related disorders: Celiac disease, wheat allergy and non-celiac gluten sensitivity.

PubMed

Elli, Luca; Branchi, Federica; Tomba, Carolina; Villalta, Danilo; Norsa, Lorenzo; Ferretti, Francesca; Roncoroni, Leda; Bardella, Maria Teresa

2015-06-21

Cereal crops and cereal consumption have had a vital role in Mankind's history. In the recent years gluten ingestion has been linked with a range of clinical disorders. Gluten-related disorders have gradually emerged as an epidemiologically relevant phenomenon with an estimated global prevalence around 5%. Celiac disease, wheat allergy and non-celiac gluten sensitivity represent different gluten-related disorders. Similar clinical manifestations can be observed in these disorders, yet there are peculiar pathogenetic pathways involved in their development. Celiac disease and wheat allergy have been extensively studied, while non-celiac gluten sensitivity is a relatively novel clinical entity, believed to be closely related to other gastrointestinal functional syndromes. The diagnosis of celiac disease and wheat allergy is based on a combination of findings from the patient's clinical history and specific tests, including serology and duodenal biopsies in case of celiac disease, or laboratory and functional assays for wheat allergy. On the other hand, non-celiac gluten sensitivity is still mainly a diagnosis of exclusion, in the absence of clear-cut diagnostic criteria. A multimodal pragmatic approach combining findings from the clinical history, symptoms, serological and histological tests is required in order to reach an accurate diagnosis. A thorough knowledge of the differences and overlap in clinical presentation among gluten-related disorders, and between them and other gastrointestinal disorders, will help clinicians in the process of differential diagnosis.

Pre-launch estimates for GLAST sensitivity to dark matter annihilation signals

DOE PAGES

Baltz, E. A.; Berenji, B.; Bertone, G.; ...

2008-07-17

Here, we investigate the sensitivity of the Gamma-ray Large Area Space Telescope (GLAST) to indirectly detect weakly interacting massive particles (WIMPs) through the γ-ray signal that their pair annihilation produces. WIMPs are among the favorite candidates to explain the compelling evidence that about 80% of the mass in the Universe is non-baryonic dark matter (DM). They are serendipitously motivated by various extensions of the standard model of particle physics such as Supersymmetry and Universal Extra Dimensions (UED). With its unprecedented sensitivity and its very large energy range (20 MeV to more than 300 GeV) the main instrument on board themore » GLAST satellite, the Large Area Telescope (LAT), will open a new window of discovery. As our estimates show, the LAT will be able to detect an indirect DM signature for a large class of WIMP models given a cuspy profile for the DM distribution. Using the current state of the art Monte Carlo and event reconstruction software developed within the LAT collaboration, we present preliminary sensitivity studies for several possible sources inside and outside the Galaxy. Lastly, we also discuss the potential of the LAT to detect UED via the electron/positron channel. Diffuse background modeling and other background issues that will be important in setting limits or seeing a signal are presented.« less

Conditionally activating optical contrast agent with enhanced sensitivity via gold nanoparticle plasmon energy transfer: feasibility study.

PubMed

Kang, Kyung Aih; Wang, Jianting

2014-12-07

Molecular sensing/imaging utilizing fluorophores has been one of the most frequently used techniques in biomedical research. As for any molecular imaging techniques, fluorescence mediated sensing always seeks for greater specificity and sensitivity. Since fluorophores emit fluorescence while their electron energy state changes, manipulating the local electromagnetic field around the fluorophores may be a way to enhance the specificity and sensitivity. Gold nanoparticles (GNPs) are known to form a very strong electromagnetic field on their surface [i.e., surface plasmon field (SPF)], upon receiving photonic energy. The level of fluorescence change by GNP-SPF may range from complete quenching to extensive enhancement, depending upon the SPF strength, excitation and emission wavelengths, and quantum yield of the fluorophore. Here, we report a novel design that utilizes BOTH fluorescence quenching and enhancement abilities of the GNP in one single nano-entity, providing high specificity and sensitivity. The construct utilizes a specially designed molecular dual-spacer that places the fluorphore at the location with an appropriate GNP-SFP strength before and after exposed to the biomarker. A model system to test the concept was an optical signal mediator activated by urokinase-type plasminogen activator (uPA; breast cancer secreting enzyme). The resulting contrast agent shows less than 10% of the natural fluorescence but, in the presence of uPA, its fluorescence emission is triggered and emits its fluorescence approximately twice of the natural form. This study demonstrated that our novel design of an optical contrast agent can be conditionally activated with enhanced sensitivity, using both quenching and enhancement phenomena of fluorophores in the electromagnetic field of the appropriate strengths (in this case, locally generated by the GNP-SPF). This entity is similar to molecular beacon in terms of specificity but with greater sensitivity. In addition, it is not restricted to only DNA or RNA sensing but for any designs that cause the change in the distance between the fluorophore and GNP, upon the time of encountering biomarker of interest.

Incidence of multidrug-resistant, extensively drug-resistant and pan-drug-resistant bacteria in children hospitalized at Dr. Hasan Sadikin general hospital Bandung Indonesia

NASA Astrophysics Data System (ADS)

Adrizain, R.; Suryaningrat, F.; Alam, A.; Setiabudi, D.

2018-03-01

Antibiotic resistance has become a global issue, with 700,000 deaths attributable to multidrug-resistance (MDR) occurring each year. Centers for Disease Control and Prevention (CDC) show rapidly increasing rates of infection due to antibiotic-resistant bacteria. The aim of the study isto describe the incidence of MDR, extensively drug-resistant (XDR) and pan drug-resistant (PDR) in Enterococcus spp., Staphylococcus aureus, K. pneumonia, Acinetobacter baumanii, P. aeruginosin, and Enterobacter spp. (ESKAPE) pathogens in children admitted to Dr. Hasan Sadikin Hospital. All pediatric patients having blood culture drawn from January 2015 to December 2016 were retrospectively studied. Data include the number of drawn blood culture, number of positive results, type of bacteria, sensitivity pattern. International standard definitions for acquired resistance by ECDC and CDC was used as definitions for MDR, XDR and PDR bacteria. From January 2015 to December 2016, 299 from 2.542 (11.7%) blood culture was positive, with Staphylococcus aureus, Enterococcus spp., Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter spp., respectively 5, 6, 24, 5, 20 with total 60 (20%). The MDR and XDR pathogen found were 47 and 13 patients, respectively.

Interim Reliability Evaluation Program: analysis of the Browns Ferry, Unit 1, nuclear plant. Main report

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

Mays, S.E.; Poloski, J.P.; Sullivan, W.H.

1982-07-01

A probabilistic risk assessment (PRA) was made of the Browns Ferry, Unit 1, nuclear plant as part of the Nuclear Regulatory Commission's Interim Reliability Evaluation Program (IREP). Specific goals of the study were to identify the dominant contributors to core melt, develop a foundation for more extensive use of PRA methods, expand the cadre of experienced PRA practitioners, and apply procedures for extension of IREP analyses to other domestic light water reactors. Event tree and fault tree analyses were used to estimate the frequency of accident sequences initiated by transients and loss of coolant accidents. External events such as floods,more » fires, earthquakes, and sabotage were beyond the scope of this study and were, therefore, excluded. From these sequences, the dominant contributors to probable core melt frequency were chosen. Uncertainty and sensitivity analyses were performed on these sequences to better understand the limitations associated with the estimated sequence frequencies. Dominant sequences were grouped according to common containment failure modes and corresponding release categories on the basis of comparison with analyses of similar designs rather than on the basis of detailed plant-specific calculations.« less

Functional MR imaging and traumatic paraplegia: preliminary report.

PubMed

Sabbah, P; Lévêque, C; Pfefer, F; Nioche, C; Gay, S; Sarrazin, J L; Barouti, H; Tadie, M; Cordoliani, Y S

2000-12-01

To evaluate residual activity in the sensorimotor cortex of the lower limbs in paraplegia. 5 patients suffering from a complete paralysis after traumatic medullar lesion (ASIA=A). Clinical evaluation of motility and sensitivity. 1. Control functional MR study of the sensorimotor cortex during simultaneous movements of hands, imaginary motor task and passive hands stimulation. 2. Concerning the lower limbs, 3 fMRI conditions: 1-patient attempts to move his toes with flexion-extension, 2-mental imagery task of the same movement, 3-peripheral passive proprio-somesthesic stimulation (squeezing) of the big toes. Activations were observed in the primary sensorimotor cortex (M1), premotor regions and in the supplementary motor area (SMA) during movement and mental imaginary tasks in the control study and during attempt to move and mental imaginary tasks in the study concerning the lower limbs. Passive somesthesic stimulation generated activation posterior to the central sulcus for 2 patients. Activations in the sensorimotor cortex of the lower limbs can be generated either by attempting to move or mental evocation. In spite of a clinical evaluation of complete paraplegia, fMRI can show a persistence of sensitive anatomic conduction, confirmed by Somesthesic Evoked Potentials.

Coal gasification systems engineering and analysis, volume 2

NASA Technical Reports Server (NTRS)

1980-01-01

The major design related features of each generic plant system were characterized in a catalog. Based on the catalog and requirements data, approximately 17 designs and cost estimates were developed for MBG and alternate products. A series of generic trade studies was conducted to support all of the design studies. A set of cost and programmatic analyses were conducted to supplement the designs. The cost methodology employed for the design and sensitivity studies was documented and implemented in a computer program. Plant design and construction schedules were developed for the K-T, Texaco, and B&W MBG plant designs. A generic work breakdown structure was prepared, based on the K-T design, to coincide with TVA's planned management approach. An extensive set of cost sensitivity analyses was completed for K-T, Texaco, and B&W design. Product price competitiveness was evaluated for MBG and the alternate products. A draft management policy and procedures manual was evaluated. A supporting technology development plan was developed to address high technology risk issues. The issues were identified and ranked in terms of importance and tractability, and a plan developed for obtaining data or developing technology required to mitigate the risk.

Detailed Analysis of the Binding Mode of Vanilloids to Transient Receptor Potential Vanilloid Type I (TRPV1) by a Mutational and Computational Study

PubMed Central

Mori, Yoshikazu; Ogawa, Kazuo; Warabi, Eiji; Yamamoto, Masahiro; Hirokawa, Takatsugu

2016-01-01

Transient receptor potential vanilloid type 1 (TRPV1) is a non-selective cation channel and a multimodal sensor protein. Since the precise structure of TRPV1 was obtained by electron cryo-microscopy, the binding mode of representative agonists such as capsaicin and resiniferatoxin (RTX) has been extensively characterized; however, detailed information on the binding mode of other vanilloids remains lacking. In this study, mutational analysis of human TRPV1 was performed, and four agonists (capsaicin, RTX, [6]-shogaol and [6]-gingerol) were used to identify amino acid residues involved in ligand binding and/or modulation of proton sensitivity. The detailed binding mode of each ligand was then simulated by computational analysis. As a result, three amino acids (L518, F591 and L670) were newly identified as being involved in ligand binding and/or modulation of proton sensitivity. In addition, in silico docking simulation and a subsequent mutational study suggested that [6]-gingerol might bind to and activate TRPV1 in a unique manner. These results provide novel insights into the binding mode of various vanilloids to the channel and will be helpful in developing a TRPV1 modulator. PMID:27606946

An electrochemical biosensor for microRNA-196a detection based on cyclic enzymatic signal amplification and template-free DNA extension reaction with the adsorption of methylene blue.

PubMed

Guo, Jing; Yuan, Changjing; Yan, Qi; Duan, Qiuyue; Li, Xiaolu; Yi, Gang

2018-05-15

A simple and sensitive electrochemical biosensor was developed for microRNA-196a detection, which is of important diagnostic significance for pancreatic cancer. It was based on cyclic enzymatic signal amplification (CESA) and template-free DNA extension reaction. In the presence of microRNA-196a, duplex-specific nuclease (DSN) catalyzed the digestion of the 3'-PO 4 terminated capture probe (CP), resulting in the target recycling amplification. Meanwhile, the 3'-OH terminal of CP was exposed. Then, template-free DNA extension reaction was triggered by terminal deoxynucleotidyl transferase (TdT), producing amounts of single-stranded DNA (ssDNA). After ssDNA absorbed numerous methylene blue (MB), an ultrasensitive electrochemical readout was obtained. Based on this dual amplification mechanism, the proposed biosensor exhibited a high sensitivity for detection of microRNA-196a down to 15 aM with a linear range from 0.05 fM to 50 pM. This biosensor displayed high specificity, which could discriminate target microRNAs from one base mismatched microRNAs. It also showed good reproducibility and stability. Furthermore, it was successfully applied to the determination of microRNA-196a in plasma samples. In conclusion, with the excellent analytical performance, this biosensor might have the potential for application in clinical diagnostics of pancreatic cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Nuclear magnetic resonance proton imaging of bone pathology

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

Atlan, H.; Sigal, R.; Hadar, H.

Thirty-two patients with diversified pathology were examined with a supraconductive NMR imager using spin echo with different TR and TE to obtain T1 and T2 weighted images. They included 20 tumors (12 primary, eight metastasis), six osteomyelitis, three fractures, two osteonecrosis, and one diffuse metabolic (Gaucher) disease. In all cases except for the stress fractures, the bone pathology was clearly visualized in spite of the normal lack of signal from the compact cortical bone. Nuclear magnetic resonance (NMR) imaging proved to be at least as sensitive as radionuclide scintigraphy but much more accurate than all other imaging procedures including computedmore » tomography (CT) and angiography to assess the extension of the lesions, especially in tumors extended to soft tissue. This is due both to easy acquisition of sagittal and coronal sections and to different patterns of pathologic modifications of T1 and T2 which are beginning to be defined. It is hoped that more experience in clinical use of these patterns will help to discriminate between tumor extension and soft-tissue edema. We conclude that while radionuclide scintigraphy will probably remain the most sensitive and easy to perform screening test for bone pathology, NMR imaging, among noninvasive diagnostic procedures, appears to be at least as specific as CT. In addition, where the extension of the lesions is concerned, NMR imaging is much more informative than CT. In pathology of the spine, the easy visualization of the spinal cord should decrease the need for myelography.« less

Geant4 Developments for the Radon Electric Dipole Moment Search at TRIUMF

NASA Astrophysics Data System (ADS)

Rand, E. T.; Bangay, J. C.; Bianco, L.; Dunlop, R.; Finlay, P.; Garrett, P. E.; Leach, K. G.; Phillips, A. A.; Sumithrarachchi, C. S.; Svensson, C. E.; Wong, J.

2011-09-01

An experiment is being developed at TRIUMF to search for a time-reversal violating electric dipole moment (EDM) in odd-A isotopes of Rn. Extensive simulations of the experiment are being performed with GEANT4 to study the backgrounds and sensitivity of the proposed measurement technique involving the detection of γ rays emitted following the β decay of polarized Rn nuclei. GEANT4 developments for the RnEDM experiment include both realistic modelling of the detector geometry and full tracking of the radioactive β, γ, internal conversion, and x-ray processes, including the γ-ray angular distributions essential for measuring an atomic EDM.

Displacement sensing based on modal interference in polymer optical fibers with partially applied strain

NASA Astrophysics Data System (ADS)

Mizuno, Yosuke; Hagiwara, Sonoko; Kawa, Tomohito; Lee, Heeyoung; Nakamura, Kentaro

2018-05-01

Strain sensing based on modal interference in multimode fibers (MMFs) has been extensively studied, but no experimental or theoretical reports have been given as to how the system works when strain is applied not to the whole MMF but only to part of the MMF. Here, using a perfluorinated graded-index polymer optical fiber as the MMF, we investigate the strain sensing characteristics of this type of sensor when strain is partially applied to fiber sections with different lengths. The strain sensitivity dependence on the length of the strained section reveals that this strain sensor actually behaves as a displacement sensor.

The effects of low level microwaves on the fluidity of photoreceptor cell membrane.

PubMed

Pologea-Moraru, Roxana; Kovacs, Eugenia; Iliescu, Karina Roxana; Calota, Violeta; Sajin, Gheorghe

2002-05-15

Due to the extensive use of electromagnetic fields in everyday life, more information is required for the detection of mechanisms of interaction and the possible side effects of electromagnetic radiation on the structure and function of the organism. In this paper, we study the effects of low-power microwaves (2.45 GHz) on the membrane fluidity of rod photoreceptor cells. The retina is expected to be very sensitive to microwave irradiation due to the polar character of the photoreceptor cells [Biochim. Biophys. Acta 1273 (1995) 217] as well as to its high water content [Stud. Biophys. 81 (1981) 39].

Neutron-hole strength in the N = 81 isotones

NASA Astrophysics Data System (ADS)

Howard, A. M.; Freeman, S. J.; Schiffer, J. P.; Bloxham, T.; Clark, J. A.; Deibel, C. M.; Kay, B. P.; Parker, P. D.; Sharp, D. K.; Thomas, J. S.

2012-09-01

The distribution of neutron-hole strength has been studied in the N = 81 isotones 137Ba, 139Ce, 141Nd and 143Sm through the single-neutron removing reactions (p,d) and (3He,α), at energies of 23 and 34 MeV, respectively. Systematic cross section measurements were made at angles sensitive to the transferred angular momentum, and spectroscopic factors extracted through a distorted-wave Born approximation analysis. Application of the MacFarlane-French sum rules indicate an anomalously low summed g7/2 spectroscopic factor, most likely due to extensive fragmentation of the single-particle strength. Single-particle energies, based upon the centroids of observed strength, are presented.

Development of a SYBR Green I real-time PCR for detection and quantitation of orthopoxvirus by using Ectromelia virus.

PubMed

Cheng, Wenyu; He, Xiaobing; Jia, Huaijie; Chen, Guohua; Wang, Cong; Zhang, Jun; Jing, Zhizhong

2018-04-01

Ectromelia virus (ECTV) is the causative agent of mousepox, which has devastating effects in laboratory-mouse colonies and causes economic loss in biomedical research. More importantly, ECTV has been extensively used as an excellent model for studies of the pathogenesis and immunobiology of human smallpox. A rapid and sensitive SYBR Green I-based real-time PCR assay was developed and used for the detection and quantitation of orthopoxvirus by using ECTV in this study. Primers targeted to the highly conserved region of major core protein P4b gene of orthopoxvirus were designed and the standard plasmid was constructed. This assay was able to detect a minimum of 10 copies of standard DNA and 5 TCID 50 units of ECTV. In addition, no cross-reactions were observed with two DNA viruses, such as herpes simplex virus and swine pseudorabies virus, and one RNA virus, vesicular stomatitis virus. Furthermore, intra- and inter-assay variability data showed that this method had a highly reproducibility and reliability. Moreover, the current assay was faster and had a higher sensitivity for detection of ECTV genomic DNA in cell cultured and clinical test samples. Therefore, the high sensitivity and reproducibility of this SYBR Green real-time PCR approach is a more effective method than the conventional PCR for ECTV diagnosis and quantitation. Copyright © 2017. Published by Elsevier Ltd.

Ago2 and Dicer1 are involved in METH-induced locomotor sensitization in mice via biogenesis of miRNA.

PubMed

Liu, Dan; Zhu, Li; Ni, Tong; Guan, Fang-Lin; Chen, Yan-Jiong; Ma, Dong-Liang; Goh, Eyleen L K; Chen, Teng

2018-03-08

microRNA (miRNA) play important roles in drug addiction and act as a post-transcriptional regulator of gene expression. We previously reported extensive downregulation of miRNAs in the nucleus accumbens (NAc) of methamphetamine (METH)-sensitized mice. However, the regulatory mechanism of this METH-induced downregulation of miRNAs has yet to be elucidated. Thus, we examined METH-induced changes in the expression of miRNAs and their precursors, as well as the expression levels of mRNA and the proteins involved in miRNA biogenesis such as Dicer1 and Ago2, in the nucleus accumbens of METH-induced locomotor sensitized mice. miRNAs and Ago2 were significantly downregulated, while the expression of miRNA precursors remained unchanged or upregulated, which suggests that the downregulation of miRNAs was likely due to a reduction in Ago2-mediated splicing but unlikely to be regulated at the transcription level. Interestingly, the expression level of Dicer1, which is a potential target of METH-induced decreased miRNAs, such as miR-124, miR-212 and miR-29b, was significantly increased. In conclusion, this study indicates that miRNA biogenesis (such as Ago2 and Dicer1) and their miRNA products may have a role in the development of METH addiction. © 2018 Society for the Study of Addiction.

Culture and drug sensitivity testing among patients with pulmonary tuberculosis in Mexico: national data for 2009-2013.

PubMed

Orejel, Ivonne; Castellanos, Martin; Marín, Diana; Mendoza, Alberto; Harries, Anthony D

2016-01-01

This study documented the number and results of mycobacterial culture and drug sensitivity testing (CDST) in Mexico from 2009-2013 and assessed whether states with a higher risk of multidrug-resistant tuberculosis (MDR-TB) performed more CDST and had more cultures showing MDR-TB. Data for this longitudinal, descriptive, operational research study came from the electronic records of 31 state public health laboratories in Mexico. The total number of CDSTs was 6 470, increasing from 2 143 in the first 2 years to 4 327 in the latter 3 years. There was a significant increase in the proportion of cultures showing sensitivity to all drugs, from 53.1% to 60.9% in 2011-2013 (P < 0.001) and a significant decrease in the proportion showing MDR-TB, from 28.2% in 2009 to 19.8% in 2013 (P < 0.001). Cases of extensively drug resistant tuberculosis were < 1% per year. In the 12 states with higher risk for MDR-TB, significantly more CDSTs (2 382 test) were done in 2011-2013 than in the other 19 states (1 945 tests). Also, for each year the proportion of cultures showing MDR-TB was significantly higher in high risk MDR-TB states than in lower risk ones (P < 0.001). During the 5-year study period, CDST was scaled up in Mexico, particularly in high-risk MDR-TB states where a higher proportion of cultures showed MDR-TB. Scale up and wider coverage of CDST should continue.

Real-Time Amperometric Recording of Extracellular H2O2 in the Brain of Immunocompromised Mice: An In Vitro, Ex Vivo and In Vivo Characterisation Study

PubMed Central

Reid, Caroline H.; Finnerty, Niall J.

2017-01-01

We detail an extensive characterisation study on a previously described dual amperometric H2O2 biosensor consisting of H2O2 detection (blank) and degradation (catalase) electrodes. In vitro investigations demonstrated excellent H2O2 sensitivity and selectivity against the interferent, ascorbic acid. Ex vivo studies were performed to mimic physiological conditions prior to in vivo deployment. Exposure to brain tissue homogenate identified reliable sensitivity and selectivity recordings up to seven days for both blank and catalase electrodes. Furthermore, there was no compromise in pre- and post-implanted catalase electrode sensitivity in ex vivo mouse brain. In vivo investigations performed in anaesthetised mice confirmed the ability of the H2O2 biosensor to detect increases in amperometric current following locally perfused/infused H2O2 and antioxidant inhibitors mercaptosuccinic acid and sodium azide. Subsequent recordings in freely moving mice identified negligible effects of control saline and sodium ascorbate interference injections on amperometric H2O2 current. Furthermore, the stability of the amperometric current was confirmed over a five-day period and analysis of 24-h signal recordings identified the absence of diurnal variations in amperometric current. Collectively, these findings confirm the biosensor current responds in vivo to increasing exogenous and endogenous H2O2 and tentatively supports measurement of H2O2 dynamics in freely moving NOD SCID mice. PMID:28698470

The physiology and pathophysiology of rapamycin resistance

PubMed Central

Boylan, Joan M; Sanders, Jennifer A

2011-01-01

Rapamycin is an inhibitor of the mammalian Target of Rapamycin, mTOR, a nutrient-sensing signaling kinase and a key regulator of cell growth and proliferation. While rapamycin and related compounds have anti-tumor activity, a prevalent characteristic of cancer cells is resistance to their anti-proliferative effects. Our studies on nutrient regulation of fetal development showed that hepatocyte proliferation in the late gestation fetal rat is resistant to rapamycin. Extension of these studies to other tissues in the fetal and neonatal rat indicated that rapamycin resistance is a characteristic of normal cell proliferation in the growing organism. In hepatic cells, ribosomal biogenesis and cap-dependent protein translation were found to be relatively insensitive to the drug even though mTOR signaling was highly sensitive. Cell cycle progression was also resistant at the level of cyclin E-dependent kinase activity. Studies on the effect of rapamycin on gene expression in vitro and in vivo demonstrated that mTOR-mediated regulation of gene expression is independent of effects on cell proliferation and cannot be accounted for by functional regulation of identifiable transcription factors. Genes involved in cell metabolism were overrepresented among rapamycin-sensitive genes. We conclude that normal cellular proliferation in the context of a developing organism can be independent of mTOR signaling, that cyclin E-containing complexes are a critical locus for rapamycin sensitivity, and that mTOR functions as a modulator of metabolic gene expression in cells that are resistant to the anti-proliferative effects of the drug. PMID:21389767

Visual Search in ASD: Instructed Versus Spontaneous Local and Global Processing.

PubMed

Van der Hallen, Ruth; Evers, Kris; Boets, Bart; Steyaert, Jean; Noens, Ilse; Wagemans, Johan

2016-09-01

Visual search has been used extensively to investigate differences in mid-level visual processing between individuals with ASD and TD individuals. The current study employed two visual search paradigms with Gaborized stimuli to assess the impact of task distractors (Experiment 1) and task instruction (Experiment 2) on local-global visual processing in ASD versus TD children. Experiment 1 revealed both groups to be equally sensitive to the absence or presence of a distractor, regardless of the type of target or type of distractor. Experiment 2 revealed a differential effect of task instruction for ASD compared to TD, regardless of the type of target. Taken together, these results stress the importance of task factors in the study of local-global visual processing in ASD.

Development of batch producible hot embossing 3D nanostructured surface-enhanced Raman scattering chip technology

NASA Astrophysics Data System (ADS)

Huang, Chu-Yu; Tsai, Ming-Shiuan

2017-09-01

The main purpose of this study is to develop a batch producible hot embossing 3D nanostructured surface-enhanced Raman chip technology for high sensitivity label-free plasticizer detection. This study utilizing the AAO self-assembled uniform nano-hemispherical array barrier layer as a template to create a durable nanostructured nickel mold. With the hot embossing technique and the durable nanostructured nickel mold, we are able to batch produce the 3D Nanostructured Surface-enhanced Raman Scattering Chip with consistent quality. In addition, because of our SERS chip can be fabricated by batch processing, the fabrication cost is low. Therefore, the developed method is very promising to be widespread and extensively used in rapid chemical and biomolecular detection applications.

Manned geosynchronous mission requirements and systems analysis study extension. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

1981-01-01

A study was performed to determine the types of manned missions that will likely be performed in the late 1980's or early 1990's timeframe, to define MOTV configurations which satisfy these missions requirements, and to develop a program plan for its development. Twenty generic missions were originally defined for MOTV but, to simplify the selection process, five of these missions were selected as typical and used as Design Reference Missions. Systems and subsystems requirements were re-examined and sensitivity analyses performed to determine optimum point designs. Turnaround modes were considered to determine the most effective combination of ground based and spaced based activities. A preferred concept for the crew capsule and for the mission mode was developed.

Surface electronic structure of SmB6(111)

NASA Astrophysics Data System (ADS)

Ohtsubo, Yoshiyuki; Hagiwara, Kenta; Wang, Chengwei; Yukawa, Ryu; Horiba, Koji; Kumigashira, Hiroshi; Hirano, Wataru; Iga, Fumitoshi; Kimura, Shin-ichi

2018-05-01

Samarium hexaboride (SmB6) is the most extensively studied candidate of topological Kondo insulators. To clarify the topological origin of metallic surface states observed on the SmB6(001) surfaces, we studied the surface electronic structure of SmB6 on the other surface orientation, SmB6(111). Although the SmB6(111) surface cannot be obtained by cleaving, we successfully obtained the well-defined clean surface by high-temperature annealing of the mechanically polished single crystal of SmB6(111) in an ultra-high vacuum. The valence band spectra obtained by photoelectron spectroscopy with the bulk and surface-sensitive incident photon energies imply that the surface is covered with B6 cluster without Sm atoms.

High-Throughput, Motility-Based Sorter for Microswimmers and Gene Discovery Platform

NASA Astrophysics Data System (ADS)

Yuan, Jinzhou; Raizen, David; Bau, Haim

2015-11-01

Animal motility varies with genotype, disease progression, aging, and environmental conditions. In many studies, it is desirable to carry out high throughput motility-based sorting to isolate rare animals for, among other things, forward genetic screens to identify genetic pathways that regulate phenotypes of interest. Many commonly used screening processes are labor-intensive, lack sensitivity, and require extensive investigator training. Here, we describe a sensitive, high throughput, automated, motility-based method for sorting nematodes. Our method was implemented in a simple microfluidic device capable of sorting many thousands of animals per hour per module, and is amenable to parallelism. The device successfully enriched for known C. elegans motility mutants. Furthermore, using this device, we isolated low-abundance mutants capable of suppressing the somnogenic effects of the flp-13 gene, which regulates sleep-like quiescence in C. elegans. Subsequent genomic sequencing led to the identification of a flp-13-suppressor gene. This research was supported, in part, by NIH NIA Grant 5R03AG042690-02.

Time to foster a rational approach to preventing cardiovascular morbid events.

PubMed

Cohn, Jay N; Duprez, Daniel A

2008-07-29

Efforts to prevent atherosclerotic morbid events have focused primarily on risk factor prevention and intervention. These approaches, based on the statistical association of risk factors with events, have dominated clinical practice in the last generation. Because the cardiovascular abnormalities eventuating in morbid events are detectable in the arteries and heart before the development of symptomatic disease, recent efforts have focused on identifying the presence of these abnormalities as a more sensitive and specific guide to the need for therapy. Advances in noninvasive techniques for studying the vasculature and the left ventricle now provide the opportunity to use early disease rather than risk factors as the tool for clinical decision making. A disease scoring system has been developed using 10 tests of vascular and cardiac function and structure. More extensive data to confirm the sensitivity and specificity of this scoring system and to demonstrate its utility in tracking the response to therapy are needed to justify widespread application in clinical practice.

Sensitizing pathogens to antibiotics using the CRISPR-Cas system.

PubMed

Goren, Moran; Yosef, Ido; Qimron, Udi

2017-01-01

The extensive use of antibiotics over the last century has resulted in a significant artificial selection pressure for antibiotic-resistant pathogens to evolve. Various strategies to fight these pathogens have been introduced including new antibiotics, naturally-derived enzymes/peptides that specifically target pathogens and bacteriophages that lyse these pathogens. A new tool has recently been introduced in the fight against drug-resistant pathogens-the prokaryotic defense mechanism-clustered regularly interspaced short palindromic repeats-CRISPR associated (CRISPR-Cas) system. The CRISPR-Cas system acts as a nuclease that can be guided to cleave any target DNA, allowing sophisticated, yet feasible, manipulations of pathogens. Here, we review pioneering studies that use the CRISPR-Cas system to specifically edit bacterial populations, eliminate their resistance genes and combine these two strategies in order to produce an artificial selection pressure for antibiotic-sensitive pathogens. We suggest that intelligent design of this system, along with efficient delivery tools into pathogens, may significantly reduce the threat of antibiotic-resistant pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Numerical analysis of hypersonic turbulent film cooling flows

NASA Technical Reports Server (NTRS)

Chen, Y. S.; Chen, C. P.; Wei, H.

1992-01-01

As a building block, numerical capabilities for predicting heat flux and turbulent flowfields of hypersonic vehicles require extensive model validations. Computational procedures for calculating turbulent flows and heat fluxes for supersonic film cooling with parallel slot injections are described in this study. Two injectant mass flow rates with matched and unmatched pressure conditions using the database of Holden et al. (1990) are considered. To avoid uncertainties associated with the boundary conditions in testing turbulence models, detailed three-dimensional flowfields of the injection nozzle were calculated. Two computational fluid dynamics codes, GASP and FDNS, with the algebraic Baldwin-Lomax and k-epsilon models with compressibility corrections were used. It was found that the B-L model which resolves near-wall viscous sublayer is very sensitive to the inlet boundary conditions at the nozzle exit face. The k-epsilon models with improved wall functions are less sensitive to the inlet boundary conditions. The testings show that compressibility corrections are necessary for the k-epsilon model to realistically predict the heat fluxes of the hypersonic film cooling problems.

Tackling CO Poisoning with Single Atom Alloy Catalysts

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

Liu, Jilei; Lucci, Felicia R.; Yang, Ming

2016-05-01

Platinum (Pt) catalysts are extensively used in the chemical industry and as electrocatalysts in fuel cells. Pt is notorious for its sensitivity to poisoning by strong CO adsorption. Here we demonstrate that the single atom alloy (SAA) strat-egy applied to Pt reduces the binding strength of CO while maintaining catalytic performance. By using surface sensi-tive studies, we accurately determined the binding strength of CO to different Pt ensembles, and this in turn guided the preparation of PtCu alloy nanoparticles. The atomic ratio Pt:Cu = 1:120 yielded a SAA which exhibited excellent CO tolerance in H2 activation, the key elementary stepmore » for hy-drogenation and hydrogen electro-oxidation. As a probe reaction, the selective hydrogenation of acetylene to ethene was performed under flow conditions on the SAA nanopar-ticles supported on alumina without activity loss in the pres-ence of CO. The ability to maintain reactivity in the presence of CO is vital to other industrial reactions including fuel reforming and methanol/ethanol fuel cells.« less

Auditory temporal processing skills in musicians with dyslexia.

PubMed

Bishop-Liebler, Paula; Welch, Graham; Huss, Martina; Thomson, Jennifer M; Goswami, Usha

2014-08-01

The core cognitive difficulty in developmental dyslexia involves phonological processing, but adults and children with dyslexia also have sensory impairments. Impairments in basic auditory processing show particular links with phonological impairments, and recent studies with dyslexic children across languages reveal a relationship between auditory temporal processing and sensitivity to rhythmic timing and speech rhythm. As rhythm is explicit in music, musical training might have a beneficial effect on the auditory perception of acoustic cues to rhythm in dyslexia. Here we took advantage of the presence of musicians with and without dyslexia in musical conservatoires, comparing their auditory temporal processing abilities with those of dyslexic non-musicians matched for cognitive ability. Musicians with dyslexia showed equivalent auditory sensitivity to musicians without dyslexia and also showed equivalent rhythm perception. The data support the view that extensive rhythmic experience initiated during childhood (here in the form of music training) can affect basic auditory processing skills which are found to be deficient in individuals with dyslexia. Copyright © 2014 John Wiley & Sons, Ltd.

Development of an Internet Security Policy for health care establishments.

PubMed

Ilioudis, C; Pangalos, G

2000-01-01

The Internet provides unprecedented opportunities for interaction and data sharing among health care providers, patients and researchers. However, the advantages provided by the Internet come with a significantly greater element of risk to the confidentiality and integrity of information. This paper defines the basic security requirements that must be addressed in order to use the Internet to safely transmit patient and/or other sensitive Health Care information. It describes a suitable Internet Security Policy for Health Care Establishments and provides the set of technical measures that are needed for its implementation. The proposed security policy and technical approaches have been based on an extensive study of the related recommendations from the security and standard groups both in EU amid USA and our related work and experience. The results have been utilized in the framework of the Intranet Health Clinic project, where the use of the Internet for the transmission of sensitive Health Care information is of vital importance.

Triaminoguanidinium dinitramide-calculations, synthesis and characterization of a promising energetic compound.

PubMed

Klapötke, Thomas M; Stierstorfer, Jörg

2008-08-07

The highly energetic compound 1,3,5-triaminoguanidinium dinitramide (1) was prepared in high yield (82%) according to a new synthesis by the reaction of potassium dinitramide and triaminoguanidinium perchlorate. The heat of formation was calculated in an extensive computational study (CBS-4M). With this the detonation parameters of compound were computed using the EXPLO5 software: D = 8796 m s(-1), p = 299 kbar. In addition, a full characterization of the chemical properties (single X-ray diffraction, IR and Raman spectroscopy, multinuclear NMR spectroscopy, mass spectrometry and elemental analysis) as well as of the energetic characteristics (differential scanning calorimetry, thermal safety calorimetry, impact, friction and electrostatic tests) is given in this work. Due to the high impact (2 J) and friction sensitivity (24 N) several attempts to reduce these sensitivities were performed by the addition of wax. The performance of was tested applying a "Koenen" steel sleeve test resulting in a critical diameter of > or =10 mm.

Terahertz sensing of chlorpyrifos-methyl using metamaterials.

PubMed

Xu, Wendao; Xie, Lijuan; Zhu, Jianfei; Wang, Wei; Ye, Zunzhong; Ma, Yungui; Tsai, Chao-Yin; Chen, Suming; Ying, Yibin

2017-03-01

By squeezing electromagnetic energy into small volumes near a metal-dielectric interface, plasmonics provide many routes to enhance and manipulate light-matter interactions, which presents new strategies for signal enhancing technologies. As an extension of the ideas of plasmonics to the terahertz (THz) range, metamaterials have shown great potential in sensing applications. In this study, terahertz time-domain spectroscopy (THz-TDS) combined with metamaterials was used to detect chlorpyrifos-methyl (CM), which is one type of the broad-spectrum organophosphorus pesticides. The results demonstrate that sensitivity is greatly improved using THz metamaterials, with the limit of detection (LOD) of CM reaching 0.204mgL -1 , which is lower than the World Health Organization's provisional guideline limit for CM in vegetables (1mgL -1 ). The results indicated that THz spectroscopy combined with metamaterials could be a valuable method for highly sensitive THz applications, presenting a new strategy for food quality and safety control in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differential sensitivity to regional-scale drought in six central US grasslands.

PubMed

Knapp, Alan K; Carroll, Charles J W; Denton, Elsie M; La Pierre, Kimberly J; Collins, Scott L; Smith, Melinda D

2015-04-01

Terrestrial ecosystems often vary dramatically in their responses to drought, but the reasons for this are unclear. With climate change forecasts for more frequent and extensive drought in the future, a more complete understanding of the mechanisms that determine differential ecosystem sensitivity to drought is needed. In 2012, the Central US experienced the fourth largest drought in a century, with a regional-scale 40% reduction in growing season precipitation affecting ecosystems ranging from desert grassland to mesic tallgrass prairie. This provided an opportunity to assess ecosystem sensitivity to a drought of common magnitude in six native grasslands. We tested the prediction that drought sensitivity is inversely related to mean annual precipitation (MAP) by quantifying reductions in aboveground net primary production (ANPP). Long-term ANPP data available for each site (mean length = 16 years) were used as a baseline for calculating reductions in ANPP, and drought sensitivity was estimated as the reduction in ANPP per millimeter reduction in precipitation. Arid grasslands were the most sensitive to drought, but drought responses and sensitivity varied by more than twofold among the six grasslands, despite all sites experiencing 40% reductions in growing season precipitation. Although drought sensitivity generally decreased with increasing MAP as predicted, there was evidence that the identity and traits of the dominant species, as well as plant functional diversity, influenced sensitivity. A more comprehensive understanding of the mechanisms leading to differences in drought sensitivity will require multi-site manipulative experiments designed to assess both biotic and abiotic determinants of ecosystem sensitivity.

Upscaling Participatory Action and Videos for Agriculture and Nutrition (UPAVAN) trial comparing three variants of a nutrition-sensitive agricultural extension intervention to improve maternal and child nutritional outcomes in rural Odisha, India: study protocol for a cluster randomised controlled trial.

PubMed

Kadiyala, Suneetha; Prost, Audrey; Harris-Fry, Helen; O'Hearn, Meghan; Pradhan, Ronali; Pradhan, Shibananth; Mishra, Naba Kishore; Rath, Suchitra; Nair, Nirmala; Rath, Shibanand; Tripathy, Prasantha; Krishnan, Sneha; Koniz-Booher, Peggy; Danton, Heather; Elbourne, Diana; Sturgess, Joanna; Beaumont, Emma; Haghparast-Bidgoli, Hassan; Skordis-Worrall, Jolene; Mohanty, Satyanarayan; Upadhay, Avinash; Allen, Elizabeth

2018-03-09

Maternal and child undernutrition have adverse consequences for pregnancy outcomes and child morbidity and mortality, and they are associated with low educational attainment, economic productivity as an adult, and human wellbeing. 'Nutrition-sensitive' agriculture programs could tackle the underlying causes of undernutrition. This study is a four-arm cluster randomised controlled trial in Odisha, India. Interventions are as follows: (1) an agricultural extension platform of women's groups viewing and discussing videos on nutrition-sensitive agriculture (NSA) practices, and follow-up visits to women at home to encourage the adoption of new practices shown in the videos; (2) women's groups viewing and discussing videos on NSA and nutrition-specific practices, with follow-up visits; and (3) women's groups viewing and discussing videos on NSA and nutrition-specific practices combined with a cycle of Participatory Learning and Action meetings, with follow-up visits. All arms, including the control, receive basic nutrition training from government community frontline workers. Primary outcomes, assessed at baseline and 32 months after the start of the interventions, are (1) percentage of children aged 6-23 months consuming ≥ 4 out of 7 food groups per day and (2) mean body mass index (BMI) (kg/m 2 ) of non-pregnant, non-postpartum (gave birth > 42 days ago) mothers or female primary caregivers of children aged 0-23 months. Secondary outcomes are percentage of mothers consuming ≥ 5 out of 10 food groups per day and percentage of children's weight-for-height z-score < -2 standard deviations (SD). The unit of randomisation is a cluster, defined as one or more villages with a combined minimum population of 800 residents. There are 37 clusters per arm, and outcomes will be assessed in an average of 32 eligible households per cluster. For randomisation, clusters are stratified by distance to nearest town (< 10 km or ≥ 10 km), and low (< 30%), medium (30-70%), or high (> 70%) proportion of Scheduled Tribe or Scheduled Caste (disadvantaged) households. A process evaluation will assess the quality of implementation and mechanisms behind the intervention effects. A cost-consequence analysis will compare incremental costs and outcomes of the interventions. This trial will contribute evidence on the impacts of NSA extension through participatory, low-cost, video-based approaches on maternal and child nutrition and on whether integration with nutrition-specific goals and enhanced participatory approaches can increase these impacts. ISRCTN , ISRCTN65922679 . Registered on 21 December 2016.

Sleep and vestibular adaptation: implications for function in microgravity

NASA Technical Reports Server (NTRS)

Hobson, J. A.; Stickgold, R.; Pace-Schott, E. F.; Leslie, K. R.

1998-01-01

Optimal human performance depends upon integrated sensorimotor and cognitive functions, both of which are known to be exquisitely sensitive to loss of sleep. Under the microgravity conditions of space flight, adaptation of both sensorimotor (especially vestibular) and cognitive functions (especially orientation) must occur quickly--and be maintained--despite any concurrent disruptions of sleep that may be caused by microgravity itself, or by the uncomfortable sleeping conditions of the spacecraft. It is the three-way interaction between sleep quality, general work efficiency, and sensorimotor integration that is the subject of this paper and the focus of new work in our laboratory. To record sleep under field conditions including microgravity, we utilize a novel system called the Nightcap that we have developed and extensively tested on normal and sleep-disordered subjects. To perturb the vestibular system in ground-based studies, we utilize a variety of experimental conditions including optokinetic stimulation and both minifying and reversing goggle paradigms that have been extensively studied in relation to plasticity of the vestibulo-ocular reflex. Using these techniques we will test the hypothesis that vestibular adaptation both provokes and is enhanced by REM sleep under both ground-based and space conditions. In this paper we describe preliminary results of some of our studies.

"Intact" Carrier Doping by Pump-Pump-Probe Spectroscopy in Combination with Interfacial Charge Transfer: A Case Study of CsPbBr3 Nanocrystals.

PubMed

Wang, Junhui; Ding, Tao; Leng, Jing; Jin, Shengye; Wu, Kaifeng

2018-06-21

Carrier doping is important for semiconductor nanocrystals (NCs) as it offers a new knob to tune NCs' functionalities, in addition to size and shape control. Also, extensive studies on NC devices have revealed that under operating conditions NCs are often unintentionally doped with electrons or holes. Thus, it is essential to be able to control the doping of NCs and study the carrier dynamics of doped NCs. The extension of previously reported redox-doping methods to chemically sensitive materials, such as recently introduced perovskite NCs, has remained challenging. We introduce an "intact" carrier-doping method by performing pump-pump-probe transient absorption spectroscopy on NC-acceptor complexes. The first pump pulse is used to trigger charge transfer from the NC to the acceptor, leading to NCs doped with a band edge carrier; the following pump-probe pulses measure the dynamics of carrier-doped NCs. We performed this measurement on CsPbBr 3 NCs and deduced positive and negative trion lifetimes of 220 ± 50 and 150 ± 40 ps, respectively, for 10 nm diameter NCs, both dominated by Auger recombination. It also allowed us to identify randomly photocharged excitons in CsPbBr 3 NCs as positive trions.

Sensitive Quantification of Cannabinoids in Milk by Alkaline Saponification-Solid Phase Extraction Combined with Isotope Dilution UPLC-MS/MS.

PubMed

Wei, Binnian; McGuffey, James E; Blount, Benjamin C; Wang, Lanqing

2016-01-01

Maternal exposure to marijuana during the lactation period-either active or passive-has prompted concerns about transmission of cannabinoids to breastfed infants and possible subsequent adverse health consequences. Assessing these health risks requires a sensitive analytical approach that is able to quantitatively measure trace-level cannabinoids in breast milk. Here, we describe a saponification-solid phase extraction approach combined with ultra-high-pressure liquid chromatography-tandem mass spectrometry for simultaneously quantifying Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN) in breast milk. We demonstrate for the first time that constraints on sensitivity can be overcome by utilizing alkaline saponification of the milk samples. After extensively optimizing the saponification procedure, the validated method exhibited limits of detections of 13, 4, and 66 pg/mL for THC, CBN, and CBD, respectively. Notably, the sensitivity achieved was significantly improved, for instance, the limits of detection for THC is at least 100-fold more sensitive compared to that previously reported in the literature. This is essential for monitoring cannabinoids in breast milk resulting from passive or nonrecent active maternal exposure. Furthermore, we simultaneously acquired multiple reaction monitoring transitions for 12 C- and 13 C-analyte isotopes. This combined analysis largely facilitated data acquisition by reducing the repetitive analysis rate for samples exceeding the linear limits of 12 C-analytes. In addition to high sensitivity and broad quantitation range, this method delivers excellent accuracy (relative error within ±10%), precision (relative standard deviation <10%), and efficient analysis. In future studies, we expect this method to play a critical role in assessing infant exposure to cannabinoids through breastfeeding.

Comparison of real-time SYBR green dengue assay with real-time taqman RT-PCR dengue assay and the conventional nested PCR for diagnosis of primary and secondary dengue infection

PubMed Central

Paudel, Damodar; Jarman, Richard; Limkittikul, Kriengsak; Klungthong, Chonticha; Chamnanchanunt, Supat; Nisalak, Ananda; Gibbons, Robert; Chokejindachai, Watcharee

2011-01-01

Background: Dengue fever and dengue hemorrhagic fever are caused by dengue virus. Dengue infection remains a burning problem of many countries. To diagnose acute dengue in the early phase we improve the low cost, rapid SYBR green real time assay and compared the sensitivity and specificity with real time Taqman® assay and conventional nested PCR assay. Aims: To develop low cost, rapid and reliable real time SYBR green diagnostic dengue assay and compare with Taqman real-time assay and conventional nested PCR (modified Lanciotti). Materials and Methods: Eight cultured virus strains were diluted in tenth dilution down to undetectable level by the PCR to optimize the primer, temperature (annealing, and extension and to detect the limit of detection of the assay. Hundred and ninety three ELISA and PCR proved dengue clinical samples were tested with real time SYBR® Green assay, real time Taqman® assay to compare the sensitivity and specificity. Results: Sensitivity and specificity of real time SYBR® green dengue assay (84% and 66%, respectively) was almost comparable to those (81% and 74%) of Taqman real time PCR dengue assay. Real time SYBR® green RT-PCR was equally sensitive in primary and secondary infection while real time Taqman was less sensitive in the secondary infection. Sensitivity of real time Taqman on DENV3 (87%) was equal to SYBR green real time PCR dengue assay. Conclusion: We developed low cost rapid diagnostic SYBR green dengue assay. Further study is needed to make duplex primer assay for the serotyping of dengue virus. PMID:22363089

Differential Sensitivity to Drought in Six Central U.S. Grasslands

NASA Astrophysics Data System (ADS)

Knapp, A.; Carroll, C. J. W.; Denton, E. M.; La Pierre, K. J.; Wilcox, K. R.; Collins, S. L.; Smith, M.

2014-12-01

Terrestrial ecosystems often vary dramatically in their responses to drought, but the reasons why are unclear. With climate change forecasts for more frequent and extensive drought in the future, a more complete understanding of the mechanisms that determine differential ecosystem sensitivity to drought is needed. In 2012, the Central U.S. experienced the 4th largest drought in a century, with a regional-scale 40% reduction in growing season precipitation affecting ecosystems ranging from desert grassland to mesic tallgrass prairie. This provided an opportunity to assess ecosystem sensitivity to a drought of common magnitude in six native grasslands. We tested the prediction that drought sensitivity is inversely related to mean annual precipitation (MAP) by quantifying reductions in aboveground net primary production (ANPP). Long-term ANPP data available for each site (mean length = 16 yrs) were used as a baseline for calculating reductions in ANPP, and drought sensitivity was estimated as the reduction in ANPP per mm reduction in precipitation. Arid grasslands were the most sensitive to drought, but drought responses and sensitivity varied by more than 2-fold among the six grasslands, despite all sites experiencing 40% reductions in growing season precipitation. Although drought sensitivity generally decreased with increasing MAP as predicted, there was evidence that the identity and traits of the dominant species, as well as plant functional diversity, influenced sensitivity.

Swamp rabbits as indicators of optimal scale for bottomland forest management

Treesearch

Joanne C. Crawford; Clayton K. Nielsen; Eric M. Schauber; John W. Groninger

2014-01-01

Specialist wildlife that evolved within forest ecosystems can be sensitive to disturbance regime changes and thereby serve as indicators of optimal scale for forest management. Bottomland hardwood (BLH) forests were once extensive within the Lower Mississippi Alluvial Valley, but land cover conversion has reduced BLH by about 80 percent over the last century. Since...

The black flies of Maine

Treesearch

L.S. Bauer; J. Granett

1979-01-01

Black flies have been long-time residents of Maine and cause extensive nuisance problems for people, domestic animals, and wildlife. The black fly problem has no simple solution because of the multitude of species present, the diverse and ecologically sensitive habitats in which they are found, and the problems inherent in measuring the extent of the damage they cause...

Users guide for EASI graphics

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

Sasser, D.W.

1978-03-01

EASI (Estimate of Adversary Sequence Interruption) is an analytical technique for measuring the effectiveness of physical protection systems. EASI Graphics is a computer graphics extension of EASI which provides a capability for performing sensitivity and trade-off analyses of the parameters of a physical protection system. This document reports on the implementation of EASI Graphics and illustrates its application with some examples.

Improved test of Lorentz invariance in electrodynamics

NASA Astrophysics Data System (ADS)

Wolf, Peter; Bize, Sébastien; Clairon, André; Santarelli, Giorgio; Tobar, Michael E.; Luiten, André N.

2004-09-01

We report new results of a test of Lorentz invariance based on the comparison of a cryogenic sapphire microwave resonator and a hydrogen-maser. The experimental results are shown together with an extensive analysis of systematic effects. Previously, this experiment has set the most stringent constraint on Kennedy-Thorndike type violations of Lorentz invariance. In this work we present new data and interpret our results in the general Lorentz violating extension of the standard model of particle physics (SME). Within the photon sector of the SME, our experiment is sensitive to seven SME parameters. We marginally improve present limits on four of these, and by a factor seven to ten on the other three.

Bacterial chemoreceptors: high-performance signaling in networked arrays.

PubMed

Hazelbauer, Gerald L; Falke, Joseph J; Parkinson, John S

2008-01-01

Chemoreceptors are crucial components in the bacterial sensory systems that mediate chemotaxis. Chemotactic responses exhibit exquisite sensitivity, extensive dynamic range and precise adaptation. The mechanisms that mediate these high-performance functions involve not only actions of individual proteins but also interactions among clusters of components, localized in extensive patches of thousands of molecules. Recently, these patches have been imaged in native cells, important features of chemoreceptor structure and on-off switching have been identified, and new insights have been gained into the structural basis and functional consequences of higher order interactions among sensory components. These new data suggest multiple levels of molecular interactions, each of which contribute specific functional features and together create a sophisticated signaling device.

Bacterial chemoreceptors: high-performance signaling in networked arrays

PubMed Central

Hazelbauer, Gerald L.; Falke, Joseph J.; Parkinson, John S.

2010-01-01

Chemoreceptors are crucial components in the bacterial sensory systems that mediate chemotaxis. Chemotactic responses exhibit exquisite sensitivity, extensive dynamic range and precise adaptation. The mechanisms that mediate these high-performance functions involve not only actions of individual proteins but also interactions among clusters of components, localized in extensive patches of thousands of molecules. Recently, these patches have been imaged in native cells, important features of chemoreceptor structure and on–off switching have been identified, and new insights have been gained into the structural basis and functional consequences of higher order interactions among sensory components. These new data suggest multiple levels of molecular interactions, each of which contribute specific functional features and together create a sophisticated signaling device. PMID:18165013

How the definition of acceptable antigens and epitope analysis can facilitate transplantation of highly sensitized patients with excellent long-term graft survival.

PubMed

Heidt, Sebastiaan; Haasnoot, Geert W; Claas, Frans H J

2018-05-24

Highly sensitized patients awaiting a renal transplant have a low chance of receiving an organ offer. Defining acceptable antigens and using this information for allocation purposes can vastly enhance transplantation of this subgroup of patients, which is the essence of the Eurotransplant Acceptable Mismatch program. Acceptable antigens can be determined by extensive laboratory testing, as well as on basis of human leukocyte antigen (HLA) epitope analyses. Within the Acceptable Mismatch program, there is no effect of HLA mismatches on long-term graft survival. Furthermore, patients transplanted through the Acceptable Mismatch program have similar long-term graft survival to nonsensitized patients transplanted through regular allocation. Although HLA epitope analysis is already being used for defining acceptable HLA antigens for highly sensitized patients in the Acceptable Mismatch program, increasing knowledge on HLA antibody - epitope interactions will pave the way toward the definition of acceptable epitopes for highly sensitized patients in the future. Allocation based on acceptable antigens can facilitate transplantation of highly sensitized patients with excellent long-term graft survival.

On the role of cost-sensitive learning in multi-class brain-computer interfaces.

PubMed

Devlaminck, Dieter; Waegeman, Willem; Wyns, Bart; Otte, Georges; Santens, Patrick

2010-06-01

Brain-computer interfaces (BCIs) present an alternative way of communication for people with severe disabilities. One of the shortcomings in current BCI systems, recently put forward in the fourth BCI competition, is the asynchronous detection of motor imagery versus resting state. We investigated this extension to the three-class case, in which the resting state is considered virtually lying between two motor classes, resulting in a large penalty when one motor task is misclassified into the other motor class. We particularly focus on the behavior of different machine-learning techniques and on the role of multi-class cost-sensitive learning in such a context. To this end, four different kernel methods are empirically compared, namely pairwise multi-class support vector machines (SVMs), two cost-sensitive multi-class SVMs and kernel-based ordinal regression. The experimental results illustrate that ordinal regression performs better than the other three approaches when a cost-sensitive performance measure such as the mean-squared error is considered. By contrast, multi-class cost-sensitive learning enables us to control the number of large errors made between two motor tasks.

Rough sets and Laplacian score based cost-sensitive feature selection

PubMed Central

Yu, Shenglong

2018-01-01

Cost-sensitive feature selection learning is an important preprocessing step in machine learning and data mining. Recently, most existing cost-sensitive feature selection algorithms are heuristic algorithms, which evaluate the importance of each feature individually and select features one by one. Obviously, these algorithms do not consider the relationship among features. In this paper, we propose a new algorithm for minimal cost feature selection called the rough sets and Laplacian score based cost-sensitive feature selection. The importance of each feature is evaluated by both rough sets and Laplacian score. Compared with heuristic algorithms, the proposed algorithm takes into consideration the relationship among features with locality preservation of Laplacian score. We select a feature subset with maximal feature importance and minimal cost when cost is undertaken in parallel, where the cost is given by three different distributions to simulate different applications. Different from existing cost-sensitive feature selection algorithms, our algorithm simultaneously selects out a predetermined number of “good” features. Extensive experimental results show that the approach is efficient and able to effectively obtain the minimum cost subset. In addition, the results of our method are more promising than the results of other cost-sensitive feature selection algorithms. PMID:29912884

Lyapunov exponents, covariant vectors and shadowing sensitivity analysis of 3D wakes: from laminar to chaotic regimes

NASA Astrophysics Data System (ADS)

Wang, Qiqi; Rigas, Georgios; Esclapez, Lucas; Magri, Luca; Blonigan, Patrick

2016-11-01

Bluff body flows are of fundamental importance to many engineering applications involving massive flow separation and in particular the transport industry. Coherent flow structures emanating in the wake of three-dimensional bluff bodies, such as cars, trucks and lorries, are directly linked to increased aerodynamic drag, noise and structural fatigue. For low Reynolds laminar and transitional regimes, hydrodynamic stability theory has aided the understanding and prediction of the unstable dynamics. In the same framework, sensitivity analysis provides the means for efficient and optimal control, provided the unstable modes can be accurately predicted. However, these methodologies are limited to laminar regimes where only a few unstable modes manifest. Here we extend the stability analysis to low-dimensional chaotic regimes by computing the Lyapunov covariant vectors and their associated Lyapunov exponents. We compare them to eigenvectors and eigenvalues computed in traditional hydrodynamic stability analysis. Computing Lyapunov covariant vectors and Lyapunov exponents also enables the extension of sensitivity analysis to chaotic flows via the shadowing method. We compare the computed shadowing sensitivities to traditional sensitivity analysis. These Lyapunov based methodologies do not rely on mean flow assumptions, and are mathematically rigorous for calculating sensitivities of fully unsteady flow simulations.

Rough sets and Laplacian score based cost-sensitive feature selection.

PubMed

Yu, Shenglong; Zhao, Hong

2018-01-01

Cost-sensitive feature selection learning is an important preprocessing step in machine learning and data mining. Recently, most existing cost-sensitive feature selection algorithms are heuristic algorithms, which evaluate the importance of each feature individually and select features one by one. Obviously, these algorithms do not consider the relationship among features. In this paper, we propose a new algorithm for minimal cost feature selection called the rough sets and Laplacian score based cost-sensitive feature selection. The importance of each feature is evaluated by both rough sets and Laplacian score. Compared with heuristic algorithms, the proposed algorithm takes into consideration the relationship among features with locality preservation of Laplacian score. We select a feature subset with maximal feature importance and minimal cost when cost is undertaken in parallel, where the cost is given by three different distributions to simulate different applications. Different from existing cost-sensitive feature selection algorithms, our algorithm simultaneously selects out a predetermined number of "good" features. Extensive experimental results show that the approach is efficient and able to effectively obtain the minimum cost subset. In addition, the results of our method are more promising than the results of other cost-sensitive feature selection algorithms.

The transition from diffuse to focused extension: Modeled evolution of the West Antarctic Rift system

NASA Astrophysics Data System (ADS)

Huerta, Audrey D.; Harry, Dennis L.

2007-03-01

Two distinct stages of extension are recognized in the West Antarctic Rift system (WARS). During the first stage, beginning in the Late Cretaceous, extension was broadly distributed throughout much of West Antarctica. A second stage of extension in the late Paleogene was focused primarily in the Victoria Land Basin, near the boundary with the East Antarctic craton. The transition to focused extension was roughly coeval with volcanic activity and strike-slip faulting in the adjacent Transantarctic Mountains. This spatial and temporal correspondence suggests that the transition in extensional style could be the result of a change in plate motions or impingement of a plume. Here we use finite element models to study the processes and conditions responsible for the two-stage evolution of rifting in the WARS. Model results indicate that the transition from a prolonged period of broadly distributed extension to a later period of focused rifting did not require a change in the regional stress regime (changes in plate motion), or deep mantle thermal state (impingement of a plume). Instead, we attribute the transition from diffuse to focused extension to an early stage dominated by the initially weak accreted lithosphere of West Antarctica, and a later stage that concentrated around a secondary weakness located at the boundary between the juvenile West Antarctica lithosphere and Precambrian East Antarctic craton. The modeled transition in extension from the initially weak West Antarctica region to the secondary weakness at the West Antarctic-East Antarctic boundary is precipitated by strengthening of the West Antarctica lithosphere during syn-extensional thinning and cooling. The modeled syn-extensional strengthening of the WARS lithosphere promotes a wide-rift mode of extension between 105 and ˜ 65 Ma. By ˜ 65 Ma most of the extending WARS region becomes stronger than the area immediately adjacent to the East Antarctic craton and extension becomes concentrated near the East Antarctic/West Antarctic boundary, forming the Victoria Land Basin region. Mantle necking in this region leads to syn-extensional weakening that promotes a narrow-rift mode of extension that becomes progressively more focused with time, resulting in formation of the Terror Rift in the western Victoria Land Basin. The geodynamic models demonstrate that the transition from diffuse to focused extension occurs only under a limited set of initial and boundary conditions, and is particularly sensitive to the pre-rift thermal state of the crust and upper mantle. Models that predict diffuse extension in West Antarctica followed by localization of rifting near the boundary between East and West Antarctica require upper mantle temperatures of 730 ± 50 °C and sufficient concentration of heat producing elements in the crust to account for ˜ 50% of the upper mantle temperature. Models with upper mantle temperatures < ca. 680 °C and/or less crustal heat production initially undergo diffuse extension in West Antarctica, and quickly develop a lithospheric neck at the model edge furthest from East Antarctica. Models with upper mantle temperatures > ca. 780 °C do not develop focused rifts, and predict indefinite diffuse extension in West Antarctica.

Learning from Higgs physics at future Higgs factories

DOE PAGES

Gu, Jiayin; Li, Honglei; Liu, Zhen; ...

2017-12-29

Future Higgs factories can reach impressive precision on Higgs property measurements. In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explored its sensitivity to new physics models at the electron-positron colliders. In particular, we studied two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weakly-interacting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong interacting models as examples of strong dynamics. We performed a global fit to various Higgs searchmore » channels to obtain the 95% C.L. constraints on the model parameter space. In the SM with a singlet extension, we obtained the limits on the singlet-doublet mixing angle sin(theta), as well as the more general Wilson coefficients of the induced higher dimensional operators. In the 2HDM, we analyzed tree level effects in tan(beta) vs. cos(beta-alpha) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for different types of 2HDM. In strong dynamics models, we obtained lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish different models. Here, we also compared the sensitivity of various future Higgs factories, namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).« less

Learning from Higgs physics at future Higgs factories

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

Gu, Jiayin; Li, Honglei; Liu, Zhen

Future Higgs factories can reach impressive precision on Higgs property measurements. In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explored its sensitivity to new physics models at the electron-positron colliders. In particular, we studied two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weakly-interacting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong interacting models as examples of strong dynamics. We performed a global fit to various Higgs searchmore » channels to obtain the 95% C.L. constraints on the model parameter space. In the SM with a singlet extension, we obtained the limits on the singlet-doublet mixing angle sin(theta), as well as the more general Wilson coefficients of the induced higher dimensional operators. In the 2HDM, we analyzed tree level effects in tan(beta) vs. cos(beta-alpha) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for different types of 2HDM. In strong dynamics models, we obtained lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish different models. Here, we also compared the sensitivity of various future Higgs factories, namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).« less

MITIE: Simultaneous RNA-Seq-based transcript identification and quantification in multiple samples.

PubMed

Behr, Jonas; Kahles, André; Zhong, Yi; Sreedharan, Vipin T; Drewe, Philipp; Rätsch, Gunnar

2013-10-15

High-throughput sequencing of mRNA (RNA-Seq) has led to tremendous improvements in the detection of expressed genes and reconstruction of RNA transcripts. However, the extensive dynamic range of gene expression, technical limitations and biases, as well as the observed complexity of the transcriptional landscape, pose profound computational challenges for transcriptome reconstruction. We present the novel framework MITIE (Mixed Integer Transcript IdEntification) for simultaneous transcript reconstruction and quantification. We define a likelihood function based on the negative binomial distribution, use a regularization approach to select a few transcripts collectively explaining the observed read data and show how to find the optimal solution using Mixed Integer Programming. MITIE can (i) take advantage of known transcripts, (ii) reconstruct and quantify transcripts simultaneously in multiple samples, and (iii) resolve the location of multi-mapping reads. It is designed for genome- and assembly-based transcriptome reconstruction. We present an extensive study based on realistic simulated RNA-Seq data. When compared with state-of-the-art approaches, MITIE proves to be significantly more sensitive and overall more accurate. Moreover, MITIE yields substantial performance gains when used with multiple samples. We applied our system to 38 Drosophila melanogaster modENCODE RNA-Seq libraries and estimated the sensitivity of reconstructing omitted transcript annotations and the specificity with respect to annotated transcripts. Our results corroborate that a well-motivated objective paired with appropriate optimization techniques lead to significant improvements over the state-of-the-art in transcriptome reconstruction. MITIE is implemented in C++ and is available from http://bioweb.me/mitie under the GPL license.

Computer-animated stimuli to measure motion sensitivity: constraints on signal design in the Jacky dragon

PubMed Central

Rieucau, Guillaume; Burke, Darren

2017-01-01

Abstract Identifying perceptual thresholds is critical for understanding the mechanisms that underlie signal evolution. Using computer-animated stimuli, we examined visual speed sensitivity in the Jacky dragon Amphibolurus muricatus, a species that makes extensive use of rapid motor patterns in social communication. First, focal lizards were tested in discrimination trials using random-dot kinematograms displaying combinations of speed, coherence, and direction. Second, we measured subject lizards’ ability to predict the appearance of a secondary reinforcer (1 of 3 different computer-generated animations of invertebrates: cricket, spider, and mite) based on the direction of movement of a field of drifting dots by following a set of behavioural responses (e.g., orienting response, latency to respond) to our virtual stimuli. We found an effect of both speed and coherence, as well as an interaction between these 2 factors on the perception of moving stimuli. Overall, our results showed that Jacky dragons have acute sensitivity to high speeds. We then employed an optic flow analysis to match the performance to ecologically relevant motion. Our results suggest that the Jacky dragon visual system may have been shaped to detect fast motion. This pre-existing sensitivity may have constrained the evolution of conspecific displays. In contrast, Jacky dragons may have difficulty in detecting the movement of ambush predators, such as snakes and of some invertebrate prey. Our study also demonstrates the potential of the computer-animated stimuli technique for conducting nonintrusive tests to explore motion range and sensitivity in a visually mediated species. PMID:29491965

Serodiagnosis of Tuberculosis: Comparison of Immunoglobulin A (IgA) Response to Sulfolipid I with IgG and IgM Responses to 2,3-Diacyltrehalose, 2,3,6-Triacyltrehalose, and Cord Factor Antigens

PubMed Central

Julián, Esther; Matas, Lurdes; Pérez, Andrés; Alcaide, José; Lanéelle, Marie-Antoinette; Luquin, Marina

2002-01-01

Nonpeptidic antigens from the Mycobacterium tuberculosis cell wall are the focus of extensive studies to determine their potential role as protective antigens or serological markers of tuberculous disease. Regarding this latter role and using an enzyme-linked immunosorbent assay, we have made a comparative study of the immunoglobulin G (IgG), IgM, and IgA antibody responses to four trehalose-containing glycolipids purified from M. tuberculosis: diacyltrehaloses, triacyltrehaloses, cord factor, and sulfolipid I (SL-I). Sera from 92 tuberculosis patients (taken before starting antituberculosis treatment) and a wide group of control individuals (84 sera from healthy donors, including purified protein derivative-negative, -positive, healed, and vaccinated individuals, and 52 sera from nontuberculous pneumonia patients), all from Spain, were studied. The results indicated a significantly elevated IgG and IgA antibody response in tuberculosis patients, compared with controls, with all the antigens used. SL-I was the best antigen studied, showing test sensitivities and specificities for IgG of 81 and 77.6%, respectively, and of 66 and 87.5% for IgA. Using this antigen and combining IgA and IgG antibody detection, high test specificity was achieved (93.7%) with a sensitivity of 67.5%. Currently, it is widely accepted that it is not possible to achieve sensitivities above 80% in tuberculosis serodiagnosis when using one antigen alone. Thus, we conclude that SL-I, in combination with other antigenic molecules, could be a useful antigen for tuberculosis serodiagnosis. PMID:12354881

Does the Superior Colliculus Control Perceptual Sensitivity or Choice Bias during Attention? Evidence from a Multialternative Decision Framework

PubMed Central

Steinmetz, Nicholas A.; Moore, Tirin; Knudsen, Eric I.

2017-01-01

Distinct networks in the forebrain and the midbrain coordinate to control spatial attention. The critical involvement of the superior colliculus (SC)—the central structure in the midbrain network—in visuospatial attention has been shown by four seminal, published studies in monkeys (Macaca mulatta) performing multialternative tasks. However, due to the lack of a mechanistic framework for interpreting behavioral data in such tasks, the nature of the SC's contribution to attention remains unclear. Here we present and validate a novel decision framework for analyzing behavioral data in multialternative attention tasks. We apply this framework to re-examine the behavioral evidence from these published studies. Our model is a multidimensional extension to signal detection theory that distinguishes between two major classes of attentional mechanisms: those that alter the quality of sensory information or “sensitivity,” and those that alter the selective gating of sensory information or “choice bias.” Model-based simulations and model-based analyses of data from these published studies revealed a converging pattern of results that indicated that choice-bias changes, rather than sensitivity changes, were the primary outcome of SC manipulation. Our results suggest that the SC contributes to attentional performance predominantly by generating a spatial choice bias for stimuli at a selected location, and that this bias operates downstream of forebrain mechanisms that enhance sensitivity. The findings lead to a testable mechanistic framework of how the midbrain and forebrain networks interact to control spatial attention. SIGNIFICANCE STATEMENT Attention involves the selection of the most relevant information for differential sensory processing and decision making. While the mechanisms by which attention alters sensory encoding (sensitivity control) are well studied, the mechanisms by which attention alters decisional weighting of sensory evidence (choice-bias control) are poorly understood. Here, we introduce a model of multialternative decision making that distinguishes bias from sensitivity effects in attention tasks. With our model, we simulate experimental data from four seminal studies that microstimulated or inactivated a key attention-related midbrain structure, the superior colliculus (SC). We demonstrate that the experimental effects of SC manipulation are entirely consistent with the SC controlling attention by changing choice bias, thereby shedding new light on how the brain mediates attention. PMID:28100734

Does the Superior Colliculus Control Perceptual Sensitivity or Choice Bias during Attention? Evidence from a Multialternative Decision Framework.

PubMed

Sridharan, Devarajan; Steinmetz, Nicholas A; Moore, Tirin; Knudsen, Eric I

2017-01-18

Distinct networks in the forebrain and the midbrain coordinate to control spatial attention. The critical involvement of the superior colliculus (SC)-the central structure in the midbrain network-in visuospatial attention has been shown by four seminal, published studies in monkeys (Macaca mulatta) performing multialternative tasks. However, due to the lack of a mechanistic framework for interpreting behavioral data in such tasks, the nature of the SC's contribution to attention remains unclear. Here we present and validate a novel decision framework for analyzing behavioral data in multialternative attention tasks. We apply this framework to re-examine the behavioral evidence from these published studies. Our model is a multidimensional extension to signal detection theory that distinguishes between two major classes of attentional mechanisms: those that alter the quality of sensory information or "sensitivity," and those that alter the selective gating of sensory information or "choice bias." Model-based simulations and model-based analyses of data from these published studies revealed a converging pattern of results that indicated that choice-bias changes, rather than sensitivity changes, were the primary outcome of SC manipulation. Our results suggest that the SC contributes to attentional performance predominantly by generating a spatial choice bias for stimuli at a selected location, and that this bias operates downstream of forebrain mechanisms that enhance sensitivity. The findings lead to a testable mechanistic framework of how the midbrain and forebrain networks interact to control spatial attention. Attention involves the selection of the most relevant information for differential sensory processing and decision making. While the mechanisms by which attention alters sensory encoding (sensitivity control) are well studied, the mechanisms by which attention alters decisional weighting of sensory evidence (choice-bias control) are poorly understood. Here, we introduce a model of multialternative decision making that distinguishes bias from sensitivity effects in attention tasks. With our model, we simulate experimental data from four seminal studies that microstimulated or inactivated a key attention-related midbrain structure, the superior colliculus (SC). We demonstrate that the experimental effects of SC manipulation are entirely consistent with the SC controlling attention by changing choice bias, thereby shedding new light on how the brain mediates attention. Copyright © 2017 the authors 0270-6474/17/370480-32$15.00/0.

A System Dynamics Approach to Modeling the Sensitivity of Inappropriate Emergency Department Utilization

NASA Astrophysics Data System (ADS)

Behr, Joshua G.; Diaz, Rafael

Non-urgent Emergency Department utilization has been attributed with increasing congestion in the flow and treatment of patients and, by extension, conditions the quality of care and profitability of the Emergency Department. Interventions designed to divert populations to more appropriate care may be cautiously received by operations managers due to uncertainty about the impact an adopted intervention may have on the two values of congestion and profitability. System Dynamics (SD) modeling and simulation may be used to measure the sensitivity of these two, often-competing, values of congestion and profitability and, thus, provide an additional layer of information designed to inform strategic decision making.

Bacterial Metabolism of Arylsulfonates

PubMed Central

Ripin, Marilyn J.; Noon, Kerry F.; Cook, Thomas M.

1971-01-01

Pseudomonas testosteroni H-8 utilizes as sole carbon source benzene sulfonate (BS), p-toluene sulfonate (pTS), and ethylbenzene sulfonate (EBS) but not higher homologs. Growth on BS was rapid (generation time, 3 hr) and efficient (Y = 57), and resulted in accumulation of sulfate. As the culture is acid-sensitive, the medium must be heavily buffered to permit extensive growth. The BS oxidase system is inducible. Cells grown on BS, but not glutamate, oxidized BS, pTS, or EBS without lag (QO2 = 50 to 100). Oxygen uptake on BS is temperature-dependent and sensitive to cyanide. Complete oxidation of 1 μmole of BS consumed approximately 5.7 μmoles of oxygen. PMID:5553286

A conceptualisation framework for building consensus on environmental sensitivity.

PubMed

González Del Campo, Ainhoa

2017-09-15

Examination of the intrinsic attributes of a system that render it more or less sensitive to potential stressors provides further insight into the baseline environment. In impact assessment, sensitivity of environmental receptors can be conceptualised on the basis of their: a) quality status according to statutory indicators and associated thresholds or targets; b) statutory protection; or c) inherent risk. Where none of these considerations are pertinent, subjective value judgments can be applied to determine sensitivity. This pragmatic conceptual framework formed the basis of a stakeholder consultation process for harmonising degrees of sensitivity of a number of environmental criteria. Harmonisation was sought to facilitate their comparative and combined analysis. Overall, full or wide agreement was reached on relative sensitivity values for the large majority of the reviewed criteria. Consensus was easier to reach on some themes (e.g. biodiversity, water and cultural heritage) than others (e.g. population and soils). As anticipated, existing statutory measures shaped the outcomes but, ultimately, knowledge-based values prevailed. The agreed relative sensitivities warrant extensive consultation but the conceptual framework provides a basis for increasing stakeholder consensus and objectivity of baseline assessments. This, in turn, can contribute to improving the evidence-base for characterising the significance of potential impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Immediate effects of spinal manipulation on thermal pain sensitivity: an experimental study

PubMed Central

George, Steven Z; Bishop, Mark D; Bialosky, Joel E; Zeppieri, Giorgio; Robinson, Michael E

2006-01-01

Background The underlying causes of spinal manipulation hypoalgesia are largely unknown. The beneficial clinical effects were originally theorized to be due to biomechanical changes, but recent research has suggested spinal manipulation may have a direct neurophysiological effect on pain perception through dorsal horn inhibition. This study added to this literature by investigating whether spinal manipulation hypoalgesia was: a) local to anatomical areas innervated by the lumbar spine; b) correlated with psychological variables; c) greater than hypoalgesia from physical activity; and d) different for A-delta and C-fiber mediated pain perception. Methods Asymptomatic subjects (n = 60) completed baseline psychological questionnaires and underwent thermal quantitative sensory testing for A-delta and C-fiber mediated pain perception. Subjects were then randomized to ride a stationary bicycle, perform lumbar extension exercise, or receive spinal manipulation. Quantitative sensory testing was repeated 5 minutes after the intervention period. Data were analyzed with repeated measures ANOVA and post-hoc testing was performed with Bonferroni correction, as appropriate. Results Subjects in the three intervention groups did not differ on baseline characteristics. Hypoalgesia from spinal manipulation was observed in lumbar innervated areas, but not control (cervical innervated) areas. Hypoalgesic response was not strongly correlated with psychological variables. Spinal manipulation hypoalgesia for A-delta fiber mediated pain perception did not differ from stationary bicycle and lumbar extension (p > 0.05). Spinal manipulation hypoalgesia for C-fiber mediated pain perception was greater than stationary bicycle riding (p = 0.040), but not for lumbar extension (p = 0.105). Conclusion Local dorsal horn mediated inhibition of C-fiber input is a potential hypoalgesic mechanism of spinal manipulation for asymptomatic subjects, but further study is required to replicate this finding in subjects with low back pain. PMID:16911795

Extreme events in a vortex gas simulation of a turbulent half-jet

NASA Astrophysics Data System (ADS)

Suryanarayanan, Saikishan; Pathikonda, Gokul; Narasimha, Roddam

2012-11-01

Extensive simulations [arXiv:1008.2876v1 [physics.flu-dyn], BAPS.2010.DFD.LE.4] have shown that the temporally evolving vortex gas mixing layer has 3 regimes, including one which has a universal spreading rate. The present study explores the development of spatially evolving mixing layers, using a vortex gas model based on Basu et al. (1995 Appl. Math. Modelling). The effects of the velocity ratio (r) are analyzed via the most extensive simulations of this kind till date, involving up to 10000 vortices and averaging over up to 1000 convective times. While the temporal limit is approached as r approaches unity, striking features such as extreme events involving coherent structures, bending, deviation of the convection velocity from mean velocity, spatial feedback and greater sensitivity to downstream and free stream boundary conditions are observed in the half-jet (r = 0) limit. A detailed statistical analysis reveals possible causes for the large scatter across experiments, as opposed to the commonly adopted explanation of asymptotic dependence on initial conditions. Supported in part by contract no. Intel/RN/4288.

A novel high light-inducible carotenoid-binding protein complex in the thylakoid membranes of Synechocystis PCC 6803

PubMed Central

Daddy, Soumana; Zhan, Jiao; Jantaro, Saowarath; He, Chenliu; He, Qingfang; Wang, Qiang

2015-01-01

Synechocystis sp. PCC 6803 is a model cyanobacterium extensively used to study photosynthesis. Here we reveal a novel high light-inducible carotenoid-binding protein complex (HLCC) in the thylakoid membranes of Synechocystis PCC 6803 cells exposed to high intensity light. Zeaxanthin and myxoxanthophyll accounted for 29.8% and 54.8%, respectively, of the carotenoids bound to the complex. Using Blue-Native PAGE followed by 2D SDS-PAGE and mass spectrometry, we showed that the HLCC consisted of Slr1128, IsiA, PsaD, and HliA/B. We confirmed these findings by SEAD fluorescence cross-linking and anti-PsaD immuno-coprecipitation analyses. The expression of genes encoding the protein components of the HLCC was enhanced by high light illumination and artificial oxidative stress. Deletion of these proteins resulted in impaired state transition and increased sensitivity to oxidative and/or high light stress, as indicated by increased membrane peroxidation. Therefore, the HLCC protects thylakoid membranes from extensive photooxidative damage, likely via a mechanism involving state transition. PMID:25820628

Lengthening of the Stargazin Cytoplasmic Tail Increases Synaptic Transmission by Promoting Interaction to Deeper Domains of PSD-95.

PubMed

Hafner, Anne-Sophie; Penn, Andrew C; Grillo-Bosch, Dolors; Retailleau, Natacha; Poujol, Christel; Philippat, Amandine; Coussen, Françoise; Sainlos, Matthieu; Opazo, Patricio; Choquet, Daniel

2015-04-22

PSD-95 is a prominent organizer of the postsynaptic density (PSD) that can present a filamentous orientation perpendicular to the plasma membrane. Interactions between PSD-95 and transmembrane proteins might be particularly sensitive to this orientation, as "long" cytoplasmic tails might be required to reach deeper PSD-95 domains. Extension/retraction of transmembrane protein C-tails offer a new way of regulating binding to PSD-95. Using stargazin as a model, we found that enhancing the apparent length of stargazin C-tail through phosphorylation or by an artificial linker was sufficient to potentiate binding to PSD-95, AMPAR anchoring, and synaptic transmission. A linear extension of stargazin C-tail facilitates binding to PSD-95 by preferentially engaging interaction with the farthest located PDZ domains regarding to the plasma membrane, which present a greater affinity for the stargazin PDZ-domain-binding motif. Our study reveals that the concerted orientation of the stargazin C-tail and PSD-95 is a major determinant of synaptic strength. Copyright © 2015 Elsevier Inc. All rights reserved.

DAKOTA Design Analysis Kit for Optimization and Terascale

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

Adams, Brian M.; Dalbey, Keith R.; Eldred, Michael S.

2010-02-24

The DAKOTA (Design Analysis Kit for Optimization and Terascale Applications) toolkit provides a flexible and extensible interface between simulation codes (computational models) and iterative analysis methods. By employing object-oriented design to implement abstractions of the key components required for iterative systems analyses, the DAKOTA toolkit provides a flexible and extensible problem-solving environment for design and analysis of computational models on high performance computers.A user provides a set of DAKOTA commands in an input file and launches DAKOTA. DAKOTA invokes instances of the computational models, collects their results, and performs systems analyses. DAKOTA contains algorithms for optimization with gradient and nongradient-basedmore » methods; uncertainty quantification with sampling, reliability, polynomial chaos, stochastic collocation, and epistemic methods; parameter estimation with nonlinear least squares methods; and sensitivity/variance analysis with design of experiments and parameter study methods. These capabilities may be used on their own or as components within advanced strategies such as hybrid optimization, surrogate-based optimization, mixed integer nonlinear programming, or optimization under uncertainty. Services for parallel computing, simulation interfacing, approximation modeling, fault tolerance, restart, and graphics are also included.« less

A novel high light-inducible carotenoid-binding protein complex in the thylakoid membranes of Synechocystis PCC 6803.

PubMed

Daddy, Soumana; Zhan, Jiao; Jantaro, Saowarath; He, Chenliu; He, Qingfang; Wang, Qiang

2015-03-30

Synechocystis sp. PCC 6803 is a model cyanobacterium extensively used to study photosynthesis. Here we reveal a novel high light-inducible carotenoid-binding protein complex (HLCC) in the thylakoid membranes of Synechocystis PCC 6803 cells exposed to high intensity light. Zeaxanthin and myxoxanthophyll accounted for 29.8% and 54.8%, respectively, of the carotenoids bound to the complex. Using Blue-Native PAGE followed by 2D SDS-PAGE and mass spectrometry, we showed that the HLCC consisted of Slr1128, IsiA, PsaD, and HliA/B. We confirmed these findings by SEAD fluorescence cross-linking and anti-PsaD immuno-coprecipitation analyses. The expression of genes encoding the protein components of the HLCC was enhanced by high light illumination and artificial oxidative stress. Deletion of these proteins resulted in impaired state transition and increased sensitivity to oxidative and/or high light stress, as indicated by increased membrane peroxidation. Therefore, the HLCC protects thylakoid membranes from extensive photooxidative damage, likely via a mechanism involving state transition.

Endonuclease from Micrococcus luteus Which Has Activity Toward Ultraviolet-Irradiated Deoxyribonucleic Acid: Its Action on Transforming Deoxyribonucleic Acid

PubMed Central

Setlow, R. B.; Setlow, Jane K.; Carrier, W. L.

1970-01-01

An endonuclease purified from Micrococcus luteus makes single-strand breaks in ultraviolet (UV)-irradiated, native deoxyribonucleic acid (DNA). The purified endonuclease is able to reactivate UV-inactivated transforming DNA of Haemophilus influenzae, especially when the DNA is assayed on a UV-sensitive mutant of H. influenzae. After extensive endonuclease action, there is a loss of transforming DNA when assayed on both UV-sensitive and -resistant cells. The endonuclease does not affect unirradiated DNA. The results indicate that the endonuclease function is involved in the repair of biological damage resulting from UV irradiation and that the UV-sensitive mutant is deficient in this step. We interpret the data as indicating that the various steps in the repair of DNA must be well coordinated if repair is to be effective. PMID:4314478

Exploiting Temporal Collateral Sensitivity in Tumor Clonal Evolution.

PubMed

Zhao, Boyang; Sedlak, Joseph C; Srinivas, Raja; Creixell, Pau; Pritchard, Justin R; Tidor, Bruce; Lauffenburger, Douglas A; Hemann, Michael T

2016-03-24

The prevailing approach to addressing secondary drug resistance in cancer focuses on treating the resistance mechanisms at relapse. However, the dynamic nature of clonal evolution, along with potential fitness costs and cost compensations, may present exploitable vulnerabilities-a notion that we term "temporal collateral sensitivity." Using a combined pharmacological screen and drug resistance selection approach in a murine model of Ph(+) acute lymphoblastic leukemia, we indeed find that temporal and/or persistent collateral sensitivity to non-classical BCR-ABL1 drugs arises in emergent tumor subpopulations during the evolution of resistance toward initial treatment with BCR-ABL1-targeted inhibitors. We determined the sensitization mechanism via genotypic, phenotypic, signaling, and binding measurements in combination with computational models and demonstrated significant overall survival extension in mice. Additional stochastic mathematical models and small-molecule screens extended our insights, indicating the value of focusing on evolutionary trajectories and pharmacological profiles to identify new strategies to treat dynamic tumor vulnerabilities. Copyright © 2016 Elsevier Inc. All rights reserved.

Person perception and the bounded rationality of social judgment.

PubMed

Wright, J C; Dawson, V L

1988-11-01

In this article, we develop a bounded rationality view of the relation between person perception and social behavior. Two theses of this approach are that behaviors vary in their significance to observers, and that observers pursue bounded rather than global utility in forming personality impressions. Observers are expected to be sensitive to targets' overall behavioral tendencies and to the variability of their behavior across situations, but both sensitivities are bounded, being greater for behaviors that directly affect observers' outcomes. In two investigations involving extensive hourly and 6-s observations, we examined the bounded utility of people's impressions of personality, demonstrating how impression accuracy is linked to the significance of behaviors. Observers were sensitive to the organization of aggressive behaviors, but less sensitive to the organization of withdrawn behaviors, even when the consistency of those behaviors was comparable. The results clarify the relation between people's inferential shortcomings in laboratory paradigms and the bounded utility of person perception in the natural environment.

Molecular dissection of colorectal cancer in pre-clinical models identifies biomarkers predicting sensitivity to EGFR inhibitors

PubMed Central

Schütte, Moritz; Risch, Thomas; Abdavi-Azar, Nilofar; Boehnke, Karsten; Schumacher, Dirk; Keil, Marlen; Yildiriman, Reha; Jandrasits, Christine; Borodina, Tatiana; Amstislavskiy, Vyacheslav; Worth, Catherine L.; Schweiger, Caroline; Liebs, Sandra; Lange, Martin; Warnatz, Hans- Jörg; Butcher, Lee M.; Barrett, James E.; Sultan, Marc; Wierling, Christoph; Golob-Schwarzl, Nicole; Lax, Sigurd; Uranitsch, Stefan; Becker, Michael; Welte, Yvonne; Regan, Joseph Lewis; Silvestrov, Maxine; Kehler, Inge; Fusi, Alberto; Kessler, Thomas; Herwig, Ralf; Landegren, Ulf; Wienke, Dirk; Nilsson, Mats; Velasco, Juan A.; Garin-Chesa, Pilar; Reinhard, Christoph; Beck, Stephan; Schäfer, Reinhold; Regenbrecht, Christian R. A.; Henderson, David; Lange, Bodo; Haybaeck, Johannes; Keilholz, Ulrich; Hoffmann, Jens; Lehrach, Hans; Yaspo, Marie-Laure

2017-01-01

Colorectal carcinoma represents a heterogeneous entity, with only a fraction of the tumours responding to available therapies, requiring a better molecular understanding of the disease in precision oncology. To address this challenge, the OncoTrack consortium recruited 106 CRC patients (stages I–IV) and developed a pre-clinical platform generating a compendium of drug sensitivity data totalling >4,000 assays testing 16 clinical drugs on patient-derived in vivo and in vitro models. This large biobank of 106 tumours, 35 organoids and 59 xenografts, with extensive omics data comparing donor tumours and derived models provides a resource for advancing our understanding of CRC. Models recapitulate many of the genetic and transcriptomic features of the donors, but defined less complex molecular sub-groups because of the loss of human stroma. Linking molecular profiles with drug sensitivity patterns identifies novel biomarkers, including a signature outperforming RAS/RAF mutations in predicting sensitivity to the EGFR inhibitor cetuximab. PMID:28186126

Efficient approach for the detection and identification of new androgenic metabolites by applying SRM GC-CI-MS/MS: a methandienone case study.

PubMed

Polet, Michael; Van Gansbeke, Wim; Van Eenoo, Peter; Deventer, Koen

2016-07-01

Identification of anabolic androgenic steroids (AAS) is a vital issue in doping control and toxicology, and searching for metabolites with longer detection times remains an important task. Recently, a gas chromatography chemical ionization triple quadrupole mass spectrometry (GC-CI-MS/MS) method was introduced, and CI, in comparison with electron ionization (EI), proved to be capable of increasing the sensitivity significantly. In addition, correlations between AAS structure and fragmentation behavior could be revealed. This enables the search for previously unknown but expected metabolites by selection of their predicted transitions. The combination of both factors allows the setup of an efficient approach to search for new metabolites. The approach uses selected reaction monitoring which is inherently more sensitive than full scan or precursor ion scan. Additionally, structural information obtained from the structure specific CI fragmentation pattern facilitates metabolite identification. The procedure was demonstrated by a methandienone case study. Its metabolites have been studied extensively in the past, and this allowed an adequate evaluation of the efficiency of the approach. Thirty three metabolites were detected, including all relevant previously discovered metabolites. In our study, the previously reported long-term metabolite (18-nor-17β-hydroxymethyl,17α-methyl-androst-1,4,13-trien-3-one) could be detected up to 26 days by using GC-CI-MS/MS. The study proves the validity of the approach to search for metabolites of new synthetic AAS and new long-term metabolites of less studied AAS and illustrates the increase in sensitivity by using CI. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

UHE Cosmic Ray Observations Using the Cygnus Water - Array

NASA Astrophysics Data System (ADS)

Dion, Cynthia L.

1995-01-01

The CYGNUS water-Cerenkov array, consisting of five surface water-Cerenkov detectors, was built in the CYGNUS extensive air shower array at Los Alamos, New Mexico (latitude 36^circ N, longitude 107^circ W, altitude 2310 meters) to search for point sources of ultra-high energy particles (>1014 eV per particle) with the CYGNUS extensive air shower array. The water-Cerenkov detectors are used to improve the angular resolution of the extensive air shower array. This experiment searches for point sources of UHE gamma-radiation that may be of galactic or extra-galactic origin. The data set from December 1991 to January 1994 consists of data from both the water-Cerenkov array and the CYGNUS extensive air shower array. These data are combined, and the angular resolution of this combined data set is measured to be 0.34^circ+0.03 ^circ-0.04^circ. The measurement is made by observing the cosmic-ray shadowing of the Sun and the Moon. Using a subset of these data, three potential sources of UHE emission are studied: the Crab Pulsar, and the active galactic nuclei Markarian 421 and Markarian 501. A search is conducted for continuous emission from these three sources, and emission over shorter time scales. This experiment is particularly sensitive to emission over these shorter time scales. There is no evidence of UHE emission from these three sources over any time scales studied, and upper bounds to the flux of gamma radiation are determined. The flux upper limit for continuous emission from the Crab Pulsar is found to be 1.2times10^ {-13}/rm cm^2/s above 70 TeV. The flux upper limit for continuous emission from Markarian 421 is found to be 1.3times10^ {-13}/rm cm^2/s above 50 TeV. The flux upper limit for continuous emission from Markarian 501 is found to be 3.8times10^ {-13}/rm cm^2/s above 50 TeV.

Grounding line migration of Petermann Gletscher, north Greenland, detected using satellite radar interferometry

NASA Technical Reports Server (NTRS)

Rignot, Eric

1997-01-01

Ice Sheet grounding lines are sensitive indicator of changes in ice thickness, sea level or elevation of the sea bed. Here, we use the synthetic-aperture radar interferometry technique to detect the migration of thel imit of tidal flexing, or hinge line, of Petermann Gletscher, a major outlet glacier of north Greenland which develops an extensive floating tongue.

Sensitivity analysis of a pulse nutrient addition technique for estimating nutrient uptake in large streams

Treesearch

Laurence Lin; J.R. Webster

2012-01-01

The constant nutrient addition technique has been used extensively to measure nutrient uptake in streams. However, this technique is impractical for large streams, and the pulse nutrient addition (PNA) has been suggested as an alternative. We developed a computer model to simulate Monod kinetics nutrient uptake in large rivers and used this model to evaluate the...

Lung and pharyngeal abscess caused by enterotoxin G- and I-producing Staphylococcus aureus.

PubMed

Barnett, S Y; Hattotuwa, K L; Teare, L

2012-05-01

We report a particularly serious case of extensive meticillin sensitive Staphylococcal lung and pharyngeal abscess. Our patient had no significant risk factors for severe infection. The detection of enterotoxin G and I here suggest that when present together, these toxins work synergistically to produce a more virulent strain of Staphylococcus aureus. Copyright © 2011. Published by Elsevier Ltd.

Program for Infant/Toddler Caregivers. Infant/Toddler Caregiving: A Guide to Culturally Sensitive Care.

ERIC Educational Resources Information Center

Mangione, Peter L., Ed.

This guide is intended to be used in conjunction with the fourth module of the Program for Infant/Toddler Caregivers (PITC), a four-module video training course for providers of family and center day care. The videos illustrate key concepts and caregiving techniques for a specific area of care, and the guides provide extensive and in-depth…

Phenological responses of Icelandic subarctic grasslands to short-term and long-term natural soil warming.

PubMed

Leblans, Niki I W; Sigurdsson, Bjarni D; Vicca, Sara; Fu, Yongshuo; Penuelas, Josep; Janssens, Ivan A

2017-11-01

The phenology of vegetation, particularly the length of the growing season (LOS; i.e., the period from greenup to senescence), is highly sensitive to climate change, which could imply potent feedbacks to the climate system, for example, by altering the ecosystem carbon (C) balance. In recent decades, the largest extensions of LOS have been reported at high northern latitudes, but further warming-induced LOS extensions may be constrained by too short photoperiod or unfulfilled chilling requirements. Here, we studied subarctic grasslands, which cover a vast area and contain large C stocks, but for which LOS changes under further warming are highly uncertain. We measured LOS extensions of Icelandic subarctic grasslands along natural geothermal soil warming gradients of different age (short term, where the measurements started after 5 years of warming and long term, i.e., warmed since ≥50 years) using ground-level measurements of normalized difference vegetation index. We found that LOS linearly extended with on average 2.1 days per °C soil warming up to the highest soil warming levels (ca. +10°C) and that LOS had the potential to extend at least 1 month. This indicates that the warming impact on LOS in these subarctic grasslands will likely not saturate in the near future. A similar response to short- and long-term warming indicated a strong physiological control of the phenological response of the subarctic grasslands to warming and suggested that genetic adaptations and community changes were likely of minor importance. We conclude that the warming-driven extension of the LOSs of these subarctic grasslands did not saturate up to +10°C warming, and hence that growing seasons of high-latitude grasslands are likely to continue lengthening with future warming (unless genetic adaptations or species shifts do occur). This persistence of the warming-induced extension of LOS has important implications for the C-sink potential of subarctic grasslands under climate change. © 2017 John Wiley & Sons Ltd.

Evaluation of long term health-related quality of life in extensive burns: a 12-year experience in a burn center.

PubMed

Xie, Bing; Xiao, Shi-chu; Zhu, Shi-hui; Xia, Zhao-fan

2012-05-01

We sought to evaluate the long term health-related quality of life (HRQOL) in patients survived severely extensive burn and identify their clinical predicting factors correlated with HRQOL. A cross-sectional study was conducted in 20 patients survived more than 2 years with extensive burn involving ≥70% total body surface area (TBSA) between 1997 and 2009 in a burn center in Shanghai. Short Form-36 Medical Outcomes Survey (SF-36), Brief Version of Burn Specific Health Scale (BSHS-B) and Michigan Hand Outcome Questionnaire (MHQ) were used for the present evaluation. SF-36 scores were compared with a healthy Chinese population, and linear correlation analysis was performed to screen the clinical relating factors predicting physical and mental component summary (PCS and MCS) scores from SF-36. HRQOL scores from SF-36 were significantly lower in the domains of physical functioning, role limitations due to physical problems, pain, social functioning and role limitations due to emotional problems compared with population norms. Multiple linear regression analysis demonstrated that only return to work (RTW) predicted improved PCS. While age at injury, facial burns, skin grafting and length of hospital stay were correlated with MCS. Work, body image and heat sensitivity obtained the lowest BSHS-B scores in all 9 domains. Improvements of HRQOL could still be seen in BSHS-B scores in domains of simple abilities, hand function, work and affect even after a quite long interval between burns and testing. Hand function of extensive burn patients obtained relatively poor MHQ scores, especially in those without RTW. Patients with extensive burns have a poorer quality of life compared with that of general population. Relatively poor physical and psychological problems still exist even after a long period. Meanwhile, a trend of gradual improvements was noted. This information will aid clinicians in decision-making of comprehensive systematic regimens for long term rehabilitation and psychosocial treatment. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

Design and expected performance of a novel hybrid detector for very-high-energy gamma-ray astrophysics

NASA Astrophysics Data System (ADS)

Assis, P.; Barres de Almeida, U.; Blanco, A.; Conceição, R.; D'Ettorre Piazzoli, B.; De Angelis, A.; Doro, M.; Fonte, P.; Lopes, L.; Matthiae, G.; Pimenta, M.; Shellard, R.; Tomé, B.

2018-05-01

Current detectors for Very-High-Energy γ-ray astrophysics are either pointing instruments with a small field of view (Cherenkov telescopes), or large field-of-view instruments with relatively large energy thresholds (extensive air shower detectors). In this article, we propose a new hybrid extensive air shower detector sensitive in an energy region starting from about 100 GeV. The detector combines a small water-Cherenkov detector, able to provide a calorimetric measurement of shower particles at ground, with resistive plate chambers which contribute significantly to the accurate shower geometry reconstruction. A full simulation of this detector concept shows that it is able to reach better sensitivity than any previous gamma-ray wide field-of-view experiment in the sub-TeV energy region. It is expected to detect with a 5σ significance a source fainter than the Crab Nebula in one year at 100 GeV and, above 1 TeV a source as faint as 10% of it. As such, this instrument is suited to detect transient phenomena making it a very powerful tool to trigger observations of variable sources and to detect transients coupled to gravitational waves and gamma-ray bursts.

Design of a sensitive aptasensor based on magnetic microbeads-assisted strand displacement amplification and target recycling.

PubMed

Li, Ying; Ji, Xiaoting; Song, Weiling; Guo, Yingshu

2013-04-03

A cross-circular amplification system for sensitive detection of adenosine triphosphate (ATP) in cancer cells was developed based on aptamer-target interaction, magnetic microbeads (MBs)-assisted strand displacement amplification and target recycling. Here we described a new recognition probe possessing two parts, the ATP aptamer and the extension part. The recognition probe was firstly immobilized on the surface of MBs and hybridized with its complementary sequence to form a duplex. When combined with ATP, the probe changed its conformation, revealing the extension part in single-strand form, which further served as a toehold for subsequent target recycling. The released complementary sequence of the probe acted as the catalyst of the MB-assisted strand displacement reaction. Incorporated with target recycling, a large amount of biotin-tagged MB complexes were formed to stimulate the generation of chemiluminescence (CL) signal in the presence of luminol and H2O2 by incorporating with streptavidin-HRP, reaching a detection limit of ATP as low as 6.1×10(-10)M. Moreover, sample assays of ATP in Ramos Burkitt's lymphoma B cells were performed, which confirmed the reliability and practicality of the protocol. Copyright © 2013 Elsevier B.V. All rights reserved.

Investigation of contact acoustic nonlinearities on metal and composite airframe structures via intensity based health monitoring.

PubMed

Romano, P Q; Conlon, S C; Smith, E C

2013-01-01

Nonlinear structural intensity (NSI) and nonlinear structural surface intensity (NSSI) based damage detection techniques were improved and extended to metal and composite airframe structures. In this study, the measurement of NSI maps at sub-harmonic frequencies was completed to provide enhanced understanding of the energy flow characteristics associated with the damage induced contact acoustic nonlinearity mechanism. Important results include NSI source localization visualization at ultra-subharmonic (nf/2) frequencies, and damage detection results utilizing structural surface intensity in the nonlinear domain. A detection metric relying on modulated wave spectroscopy was developed and implemented using the NSSI feature. The data fusion of the intensity formulation provided a distinct advantage, as both the single interrogation frequency NSSI and its modulated wave extension (NSSI-MW) exhibited considerably higher sensitivities to damage than using single-sensor (strain or acceleration) nonlinear detection metrics. The active intensity based techniques were also extended to composite materials, and results show both NSSI and NSSI-MW can be used to detect damage in the bond line of an integrally stiffened composite plate structure with high sensitivity. Initial damage detection measurements made on an OH-58 tailboom (Penn State Applied Research Laboratory, State College, PA) indicate the techniques can be transitioned to complex airframe structures achieving high detection sensitivities with minimal sensors and actuators.

Hypersonic separated flows about "tick" configurations with sensitivity to model design

NASA Astrophysics Data System (ADS)

Moss, J. N.; O'Byrne, S.; Gai, S. L.

2014-12-01

This paper presents computational results obtained by applying the direct simulation Monte Carlo (DSMC) method for hypersonic nonequilibrium flow about "tick-shaped" model configurations. These test models produces a complex flow where the nonequilibrium and rarefied aspects of the flow are initially enhanced as the flow passes over an expansion surface, and then the flow encounters a compression surface that can induce flow separation. The resulting flow is such that meaningful numerical simulations must have the capability to account for a significant range of rarefaction effects; hence the application of the DSMC method in the current study as the flow spans several flow regimes, including transitional, slip, and continuum. The current focus is to examine the sensitivity of both the model surface response (heating, friction and pressure) and flowfield structure to assumptions regarding surface boundary conditions and more extensively the impact of model design as influenced by leading edge configuration as well as the geometrical features of the expansion and compression surfaces. Numerical results indicate a strong sensitivity to both the extent of the leading edge sharpness and the magnitude of the leading edge bevel angle. Also, the length of the expansion surface for a fixed compression surface has a significant impact on the extent of separated flow.

Electronic transfer of sensitive patient data.

PubMed

Detterbeck, A M W; Kaiser, J; Hirschfelder, U

2015-01-01

The purpose of this study was to develop decision-making aids and recommendations for dental practitioners regarding the utilization and sharing of sensitive digital patient data. In the current environment of growing digitization, healthcare professionals need detailed knowledge of secure data management to maximize confidentiality and minimize the risks involved in both archiving patient data and sharing it through electronic channels. Despite well-defined legal requirements, an all-inclusive technological solution does not currently exist. The need for a preliminary review and critical appraisal of common practices of data transfer prompted a search of the literature and the Web to identify viable methods of secure data exchange and to develop a flowchart. A strong focus was placed on the transmission of datasets both smaller than and larger than 10 MB, and on secure communication by smartphone. Although encryption of patient-related data should be routine, it is often difficult to implement. Pretty Good Privacy (PGP) and Secure/Multipurpose Internet Mail Extensions (S/MIME) are viable standards for secure e-mail encryption. Sharing of high-volume data should be accomplished with the help of file encryption. Careful handling of sensitive patient data is mandatory, and it is the end-user's responsibility to meet any requirements for encryption, preferably by using free, open-source (and hence transparent) software.

Hypersonic Separated Flows About "Tick" Configurations With Sensitivity to Model Design

NASA Technical Reports Server (NTRS)

Moss, J. N.; O'Byrne, S.; Gai, S. L.

2014-01-01

This paper presents computational results obtained by applying the direct simulation Monte Carlo (DSMC) method for hypersonic nonequilibrium flow about "tick-shaped" model configurations. These test models produces a complex flow where the nonequilibrium and rarefied aspects of the flow are initially enhanced as the flow passes over an expansion surface, and then the flow encounters a compression surface that can induce flow separation. The resulting flow is such that meaningful numerical simulations must have the capability to account for a significant range of rarefaction effects; hence the application of the DSMC method in the current study as the flow spans several flow regimes, including transitional, slip, and continuum. The current focus is to examine the sensitivity of both the model surface response (heating, friction and pressure) and flowfield structure to assumptions regarding surface boundary conditions and more extensively the impact of model design as influenced by leading edge configuration as well as the geometrical features of the expansion and compression surfaces. Numerical results indicate a strong sensitivity to both the extent of the leading edge sharpness and the magnitude of the leading edge bevel angle. Also, the length of the expansion surface for a fixed compression surface has a significant impact on the extent of separated flow.

Serendipitous findings while researching oxygen free radicals.

PubMed

Floyd, Robert A

2009-04-15

This review is based on the honor of receiving the Discovery Award from the Society of Free Radical Biology and Medicine. The review is reflective and presents our thinking that led to experiments that yielded novel observations. Critical questioning of our understanding of oxygen free radicals in biomedical problems led us to use and develop more direct and extremely sensitive methods. This included nitrone free radical spin trapping and HPLC-electrochemical detection. This technology led to the pioneering use of salicylate to trap hydroxyl free radicals and show increased flux in ischemia/reperfused brain regions and also to first sensitively detect 8-hydroxyl-2-deoxyguanosine in oxidatively damaged DNA and help assess its role in cancer development. We demonstrated that methylene blue (MB) photoinduces formation of 8-hydroxyguanine in DNA and RNA and discovered that MB sensitively photoinactivates RNA viruses, including HIV and the West Nile virus. Studies in experimental stroke led us serendipitously to discover that alpha-phenyl-tert-butylnitrone (PBN) was neuroprotective if given after the stroke. This led to extensive commercial development of NXY-059, a PBN derivative, for the treatment of stroke. More recently we discovered that PBN nitrones have potent anti-cancer activity and are active in preventing hearing loss caused by acute acoustical trauma.

Serendipitous Findings While Researching Oxygen Free Radicals

PubMed Central

Floyd, Robert A.

2009-01-01

This review is based on the honor of receiving the Discovery Award from the Society of Free Radical Biology and Medicine. The review is reflective and presents our thinking which led to experiments that yielded novel observations. Critical questioning of our understanding of oxygen free radicals in biomedical problems led us to use and develop more direct and extremely sensitive methods. This included nitrone free radical spin-trapping and HPLC-electrochemical detection. This technology led to the pioneering use of salicylate to trap hydroxyl free radicals and show increased flux in ischemia/reperfused brain regions and to also first sensitively detect 8-hydroxy-droxyguanosine (8-OHdG) in oxidative-damaged DNA and help assess its role in cancer development. We demonstrated that Methylene Blue (MB) photo-induced formation of 8-hydroxy-guanine in DNA and RNA and discovered that MB sensitively photo-inactivated RNA viruses including HIV and the West Nile Virus. Studies in experimental stroke led us to serendipitously discover that α-phenyl-tert-butylnitrone (PBN) was neuroprotective if given after the stroke. This led to extensive commercial development of NXY-059, a PBN derivative, for the treatment of stroke. More recently we discovered that PBN-nitrones have potent anti-cancer activity and are active in preventing hearing loss caused by acute acoustical trauma. PMID:19439210

Improving single molecule force spectroscopy through automated real-time data collection and quantification of experimental conditions

PubMed Central

Scholl, Zackary N.; Marszalek, Piotr E.

2013-01-01

The benefits of single molecule force spectroscopy (SMFS) clearly outweigh the challenges which include small sample sizes, tedious data collection and introduction of human bias during the subjective data selection. These difficulties can be partially eliminated through automation of the experimental data collection process for atomic force microscopy (AFM). Automation can be accomplished using an algorithm that triages usable force-extension recordings quickly with positive and negative selection. We implemented an algorithm based on the windowed fast Fourier transform of force-extension traces that identifies peaks using force-extension regimes to correctly identify usable recordings from proteins composed of repeated domains. This algorithm excels as a real-time diagnostic because it involves <30 ms computational time, has high sensitivity and specificity, and efficiently detects weak unfolding events. We used the statistics provided by the automated procedure to clearly demonstrate the properties of molecular adhesion and how these properties change with differences in the cantilever tip and protein functional groups and protein age. PMID:24001740

Waste-to-energy: A review of life cycle assessment and its extension methods.

PubMed

Zhou, Zhaozhi; Tang, Yuanjun; Chi, Yong; Ni, Mingjiang; Buekens, Alfons

2018-01-01

This article proposes a comprehensive review of evaluation tools based on life cycle thinking, as applied to waste-to-energy. Habitually, life cycle assessment is adopted to assess environmental burdens associated with waste-to-energy initiatives. Based on this framework, several extension methods have been developed to focus on specific aspects: Exergetic life cycle assessment for reducing resource depletion, life cycle costing for evaluating its economic burden, and social life cycle assessment for recording its social impacts. Additionally, the environment-energy-economy model integrates both life cycle assessment and life cycle costing methods and judges simultaneously these three features for sustainable waste-to-energy conversion. Life cycle assessment is sufficiently developed on waste-to-energy with concrete data inventory and sensitivity analysis, although the data and model uncertainty are unavoidable. Compared with life cycle assessment, only a few evaluations are conducted to waste-to-energy techniques by using extension methods and its methodology and application need to be further developed. Finally, this article succinctly summarises some recommendations for further research.

IGF-1R inhibition induces schedule-dependent sensitization of human melanoma to temozolomide

PubMed Central

Ramcharan, Roger; Aleksic, Tamara; Kamdoum, Wilfride Petnga; Gao, Shan; Pfister, Sophia X.; Tanner, Jordan; Bridges, Esther; Asher, Ruth; Watson, Amanda J.; Margison, Geoffrey P.; Woodcock, Mick; Repapi, Emmanouela; Li, Ji-Liang; Middleton, Mark R.; Macaulay, Valentine M.

2015-01-01

Prior studies implicate type 1 IGF receptor (IGF-1R) in mediating chemo-resistance. Here, we investigated whether IGF-1R influences response to temozolomide (TMZ), which generates DNA adducts that are removed by O6-methylguanine-DNA methyltransferase (MGMT), or persist causing replication-associated double-strand breaks (DSBs). Initial assessment in 10 melanoma cell lines revealed that TMZ resistance correlated with MGMT expression (r = 0.79, p = 0.009), and in MGMT-proficient cell lines, with phospho-IGF-1R (r = 0.81, p = 0.038), suggesting that TMZ resistance associates with IGF-1R activation. Next, effects of IGF-1R inhibitors (IGF-1Ri) AZ3801 and linsitinib (OSI-906) were tested on TMZ-sensitivity, cell cycle progression and DSB induction. IGF-1Ri sensitized BRAF wild-type and mutant melanoma cells to TMZ in vitro, an effect that was independent of MGMT. Cells harboring wild-type p53 were more sensitive to IGF-1Ri, and showed schedule-dependent chemo-sensitization that was most effective when IGF-1Ri followed TMZ. This sequence sensitized to clinically-achievable TMZ concentrations and enhanced TMZ-induced apoptosis. Simultaneous or prior IGF-1Ri caused less effective chemo-sensitization, associated with increased G1 population and reduced accumulation of TMZ-induced DSBs. Clinically relevant sequential (TMZ → IGF-1Ri) treatment was tested in mice bearing A375M (V600E BRAF, wild-type p53) melanoma xenografts, achieving peak plasma/tumor IGF-1Ri levels comparable to clinical Cmax, and inducing extensive intratumoral apoptosis. TMZ or IGF-1Ri caused minor inhibition of tumor growth (gradient reduction 13%, 25% respectively), while combination treatment caused supra-additive growth delay (72%) that was significantly different from control (p < 0.01), TMZ (p < 0.01) and IGF-1Ri (p < 0.05) groups. These data highlight the importance of scheduling when combining IGF-1Ri and other targeted agents with drugs that induce replication-associated DNA damage. PMID:26497996

Psychometric properties of the Late-Life Function and Disability Instrument: a systematic review

PubMed Central

2014-01-01

Background The choice of measure for use as a primary outcome in geriatric research is contingent upon the construct of interest and evidence for its psychometric properties. The Late-Life Function and Disability Instrument (LLFDI) has been widely used to assess functional limitations and disability in studies with older adults. The primary aim of this systematic review was to evaluate the current available evidence for the psychometric properties of the LLFDI. Methods Published studies of any design reporting results based on administration of the original version of the LLFDI in community-dwelling older adults were identified after searches of 9 electronic databases. Data related to construct validity (convergent/divergent and known-groups validity), test-retest reliability and sensitivity to change were extracted. Effect sizes were calculated for within-group changes and summarized graphically. Results Seventy-one studies including 17,301 older adults met inclusion criteria. Data supporting the convergent/divergent and known-groups validity for both the Function and Disability components were extracted from 30 and 18 studies, respectively. High test-retest reliability was found for the Function component, while results for the Disability component were more variable. Sensitivity to change of the LLFDI was confirmed based on findings from 25 studies. The basic lower extremity subscale and overall summary score of the Function component and limitation dimension of the Disability component were associated with the strongest relative effect sizes. Conclusions There is extensive evidence to support the construct validity and sensitivity to change of the LLFDI among various clinical populations of community-dwelling older adults. Further work is needed on predictive validity and values for clinically important change. Findings from this review can be used to guide the selection of the most appropriate LLFDI subscale for use an outcome measure in geriatric research and practice. PMID:24476510

PDF investigations of turbulent non-premixed jet flames with thin reaction zones

NASA Astrophysics Data System (ADS)

Wang, Haifeng; Pope, Stephen

2012-11-01

PDF (probability density function) modeling studies are carried out for the Sydney piloted jet flames. These Sydney flames feature much thinner reaction zones in the mixture fraction space compared to those in the well-studied Sandia piloted jet flames. The performance of the different turbulent combustion models in the Sydney flames with thin reaction zones has not been examined extensively before, and this work aims at evaluating the capability of the PDF method to represent the thin turbulent flame structures in the Sydney piloted flames. Parametric and sensitivity PDF studies are performed with respect to the different models and model parameters. A global error parameter is defined to quantify the departure of the simulation results from the experimental data, and is used to assess the performance of the different set of models and model parameters.

Increased serum baseline tryptase levels and extensive skin involvement are predictors for the severity of mast cell activation episodes in children with mastocytosis

PubMed Central

Alvarez-Twose, I.; Vañó-Galván, S.; Sánchez-Muñoz, L.; Morgado, J. M.; Matito, A.; Torrelo, A.; Jaén, P.; Schwartz, L. B.; Orfao, A.; Escribano, L

2012-01-01

Background Despite the good prognosis of pediatric mastocytosis, some patients suffer from severe mast cell (MC) mediator-associated symptoms. The aim of this study was to identify predictors for severe MC mediator release symptoms in children with mastocytosis in the skin (MIS). Methods Serum baseline total tryptase (sbT) levels in 111 children with MIS – 80 maculopapular cutaneous mastocytosis/plaque mastocytosis, 22 nodular mastocytosis, and nine diffuse cutaneous mastocytosis – were investigated as a predictive biomarker for the occurrence of MC mediator-related signs and symptoms within the first 18 months after disease onset. Results Twelve children (11%) who showed extensive cutaneous disease involving >90% of body surface area (BSA) suffered from severe symptoms requiring hospitalization, with (n = 5) or without (n = 6) management in the intensive care unit (ICU) owing to life-threatening complications. The median sbT was significantly (P < 0.001) higher in patients with extensive cutaneous disease vs those with <90% of BSA involved (45.5 vs 5.2 µg/l, respectively), as well as in children with grade 4 (severe mastocytosis-related symptoms requiring emergency therapy and hospitalization) vs those with grade <4 (46.2 vs 5.2 µg/l, respectively). Receiver operating characteristics curve analyses showed that the optimal cutoff s for sbT to predict the need for daily antimediator therapy, hospitalization, and the management in an ICU were 6.6, 15.5, and 30.8 µg/l, respectively (sensitivity and specificity of 77% and 79%, 100% and 95%, and 100% and 96%, respectively). Conclusions Increased sbT in association with extensive cutaneous involvement identifies patients at risk for severe MC activation events in pediatric mastocytosis. PMID:22458675

Increased serum baseline tryptase levels and extensive skin involvement are predictors for the severity of mast cell activation episodes in children with mastocytosis.

PubMed

Alvarez-Twose, I; Vañó-Galván, S; Sánchez-Muñoz, L; Morgado, J M; Matito, A; Torrelo, A; Jaén, P; Schwartz, L B; Orfao, A; Escribano, L

2012-06-01

Despite the good prognosis of pediatric mastocytosis, some patients suffer from severe mast cell (MC) mediator-associated symptoms. The aim of this study was to identify predictors for severe MC mediator release symptoms in children with mastocytosis in the skin (MIS). Serum baseline total tryptase (sbT) levels in 111 children with MIS - 80 maculopapular cutaneous mastocytosis/plaque mastocytosis, 22 nodular mastocytosis, and nine diffuse cutaneous mastocytosis - were investigated as a predictive biomarker for the occurrence of MC mediator-related signs and symptoms within the first 18 months after disease onset. Twelve children (11%) who showed extensive cutaneous disease involving >90% of body surface area (BSA) suffered from severe symptoms requiring hospitalization, with (n = 5) or without (n = 6) management in the intensive care unit (ICU) owing to life-threatening complications. The median sbT was significantly (P < 0.001) higher in patients with extensive cutaneous disease vs those with <90% of BSA involved (45.5 vs 5.2 μg/l, respectively), as well as in children with grade 4 (severe mastocytosis-related symptoms requiring emergency therapy and hospitalization) vs those with grade <4 (46.2 vs 5.2 μg/l, respectively). Receiver operating characteristics curve analyses showed that the optimal cutoff s for sbT to predict the need for daily antimediator therapy, hospitalization, and the management in an ICU were 6.6, 15.5, and 30.8 μg/l, respectively (sensitivity and specificity of 77% and 79%, 100% and 95%, and 100% and 96%, respectively). Increased sbT in association with extensive cutaneous involvement identifies patients at risk for severe MC activation events in pediatric mastocytosis. © 2012 John Wiley & Sons A/S.

Functional Implications of Limited Leptin Receptor and Ghrelin Receptor Coexpression in the Brain

PubMed Central

Perello, Mario; Scott, Michael M.; Sakata, Ichiro; Lee, Charlotte E.; Chuang, Jen-Chieh; Osborne-Lawrence, Sherri; Rovinsky, Sherry A.; Elmquist, Joel K.; Zigman, Jeffrey M.

2012-01-01

The hormones leptin and ghrelin act in apposition to one another in the regulation of body weight homeostasis. Interestingly, both leptin receptor expression and ghrelin receptor expression have been observed within many of the same nuclei of the central nervous system (CNS), suggesting that these hormones may act on a common population of neurons to produce changes in food intake and energy expenditure. In the present study we explored the extent of this putative direct leptin and ghrelin interaction in the CNS and addressed the question of whether a loss of ghrelin signaling would affect sensitivity to leptin. Using histological mapping of leptin receptor and ghrelin receptor expression, we found that cells containing both leptin receptors and ghrelin receptors are mainly located in the medial part of the hypothalamic arcuate nucleus. In contrast, coexpression was much less extensive elsewhere in the brain. To assess the functional consequences of this observed receptor distribution, we explored the effect of ghrelin receptor deletion on leptin sensitivity. In particular, the responses of ad libitum-fed, diet-induced obese and fasted mice to the anorectic actions of leptin were examined. Surprisingly, we found that deletion of the ghrelin receptor did not affect the sensitivity to exogenously administrated leptin. Thus, we conclude that ghrelin and leptin act largely on distinct neuronal populations and that ghrelin receptor deficiency does not affect sensitivity to the anorexigenic and body weight-lowering actions of leptin. PMID:21674492

Functional implications of limited leptin receptor and ghrelin receptor coexpression in the brain.

PubMed

Perello, Mario; Scott, Michael M; Sakata, Ichiro; Lee, Charlotte E; Chuang, Jen-Chieh; Osborne-Lawrence, Sherri; Rovinsky, Sherry A; Elmquist, Joel K; Zigman, Jeffrey M

2012-02-01

The hormones leptin and ghrelin act in apposition to one another in the regulation of body weight homeostasis. Interestingly, both leptin receptor expression and ghrelin receptor expression have been observed within many of the same nuclei of the central nervous system (CNS), suggesting that these hormones may act on a common population of neurons to produce changes in food intake and energy expenditure. In the present study we explored the extent of this putative direct leptin and ghrelin interaction in the CNS and addressed the question of whether a loss of ghrelin signaling would affect sensitivity to leptin. Using histological mapping of leptin receptor and ghrelin receptor expression, we found that cells containing both leptin receptors and ghrelin receptors are mainly located in the medial part of the hypothalamic arcuate nucleus. In contrast, coexpression was much less extensive elsewhere in the brain. To assess the functional consequences of this observed receptor distribution, we explored the effect of ghrelin receptor deletion on leptin sensitivity. In particular, the responses of ad libitum-fed, diet-induced obese and fasted mice to the anorectic actions of leptin were examined. Surprisingly, we found that deletion of the ghrelin receptor did not affect the sensitivity to exogenously administrated leptin. Thus, we conclude that ghrelin and leptin act largely on distinct neuronal populations and that ghrelin receptor deficiency does not affect sensitivity to the anorexigenic and body weight-lowering actions of leptin. Copyright © 2011 Wiley-Liss, Inc.

Extension of Pressure Measurement to 6× 10-11 Torr Using the Dynamics of the m=1 Diocotron Mode*

NASA Astrophysics Data System (ADS)

Paul, Stephen F.; Morrison, Kyle; Davidson, Ronald C.; Jenkins, Thomas

2001-10-01

Damping of the m=1 diocotron mode is used to measure neutral pressure in the Electron Diffusion Gauge (EDG). The drag exerted on the rotating plasma by collisions with neutrals is expected to excite the mode. However, previous studies in the EDG showed that the diocotron mode is more strongly damped at higher neutral pressures. The damping scaled as P-1/2 in the range from 5× 10-10 to 2× 10-7 Torr. This range has been extended from 6× 10-11 to 5× 10-7 Torr. Above 10-7 Torr, the damping increases linearly with P. Below 5× 10-9 Torr, the scaling is less sensitive, ≈ P-1/4, exhibiting a smooth transition. Sensitivity to pressure increments of less than ΔP = 1× 10-10 Torr are observed. Mode damping is correlated with the rate of expansion of the plasma, which occurs simultaneously. At high pressure, collisions with neutrals dominate the expansion, resulting in a similarly sensitive dependence on pressure. At low pressure, device asymmetries dominate the plasma expansion. Whereas plasma expansion is virtually insensitive to pressures below 5× 10-8 Torr, diocotron mode measurements have shown sensitivity over two orders of magnitude lower in pressure. Both diocotron mode damping and plasma expansion also depend similarly on electron density and magnetic field. Conditions that favor expansion (low field, high collisionality) also favor mode damping. *Research supported by the Office of Naval Research