System dynamics modeling in the evaluation of delays of care in ST-segment elevation myocardial infarction patients within a tiered health system.

PubMed

de Andrade, Luciano; Lynch, Catherine; Carvalho, Elias; Rodrigues, Clarissa Garcia; Vissoci, João Ricardo Nickenig; Passos, Guttenberg Ferreira; Pietrobon, Ricardo; Nihei, Oscar Kenji; de Barros Carvalho, Maria Dalva

2014-01-01

Mortality rates amongst ST segment elevation myocardial infarction (STEMI) patients remain high, especially in developing countries. The aim of this study was to evaluate the factors related with delays in the treatment of STEMI patients to support a strategic plan toward structural and personnel modifications in a primary hospital aligning its process with international guidelines. The study was conducted in a primary hospital localized in Foz do Iguaçu, Brazil. We utilized a qualitative and quantitative integrated analysis including on-site observations, interviews, medical records analysis, Qualitative Comparative Analysis (QCA) and System Dynamics Modeling (SD). Main cause of delays were categorized into three themes: a) professional, b) equipment and c) transportation logistics. QCA analysis confirmed four main stages of delay to STEMI patient's care in relation to the 'Door-in-Door-out' time at the primary hospital. These stages and their average delays in minutes were: a) First Medical Contact (From Door-In to the first contact with the nurse and/or physician): 7 minutes; b) Electrocardiogram acquisition and review by a physician: 28 minutes; c) ECG transmission and Percutaneous Coronary Intervention Center team feedback time: 76 minutes; and d) Patient's Transfer Waiting Time: 78 minutes. SD baseline model confirmed the system's behavior with all occurring delays and the need of improvements. Moreover, after model validation and sensitivity analysis, results suggested that an overall improvement of 40% to 50% in each of these identified stages would reduce the delay. This evaluation suggests that investment in health personnel training, diminution of bureaucracy, and management of guidelines might lead to important improvements decreasing the delay of STEMI patients' care. In addition, this work provides evidence that SD modeling may highlight areas where health system managers can implement and evaluate the necessary changes in order to improve the process of care.

System Dynamics Modeling in the Evaluation of Delays of Care in ST-Segment Elevation Myocardial Infarction Patients within a Tiered Health System

PubMed Central

de Andrade, Luciano; Lynch, Catherine; Carvalho, Elias; Rodrigues, Clarissa Garcia; Vissoci, João Ricardo Nickenig; Passos, Guttenberg Ferreira; Pietrobon, Ricardo; Nihei, Oscar Kenji; de Barros Carvalho, Maria Dalva

2014-01-01

Background Mortality rates amongst ST segment elevation myocardial infarction (STEMI) patients remain high, especially in developing countries. The aim of this study was to evaluate the factors related with delays in the treatment of STEMI patients to support a strategic plan toward structural and personnel modifications in a primary hospital aligning its process with international guidelines. Methods and Findings The study was conducted in a primary hospital localized in Foz do Iguaçu, Brazil. We utilized a qualitative and quantitative integrated analysis including on-site observations, interviews, medical records analysis, Qualitative Comparative Analysis (QCA) and System Dynamics Modeling (SD). Main cause of delays were categorized into three themes: a) professional, b) equipment and c) transportation logistics. QCA analysis confirmed four main stages of delay to STEMI patient’s care in relation to the ‘Door-in-Door-out’ time at the primary hospital. These stages and their average delays in minutes were: a) First Medical Contact (From Door-In to the first contact with the nurse and/or physician): 7 minutes; b) Electrocardiogram acquisition and review by a physician: 28 minutes; c) ECG transmission and Percutaneous Coronary Intervention Center team feedback time: 76 minutes; and d) Patient’s Transfer Waiting Time: 78 minutes. SD baseline model confirmed the system’s behavior with all occurring delays and the need of improvements. Moreover, after model validation and sensitivity analysis, results suggested that an overall improvement of 40% to 50% in each of these identified stages would reduce the delay. Conclusions This evaluation suggests that investment in health personnel training, diminution of bureaucracy, and management of guidelines might lead to important improvements decreasing the delay of STEMI patients’ care. In addition, this work provides evidence that SD modeling may highlight areas where health system managers can implement and evaluate the necessary changes in order to improve the process of care. PMID:25079362

Divergence compensation for hardware-in-the-loop simulation of stiffness-varying discrete contact in space

NASA Astrophysics Data System (ADS)

Qi, Chenkun; Zhao, Xianchao; Gao, Feng; Ren, Anye; Hu, Yan

2016-11-01

The hardware-in-the-loop (HIL) contact simulation for flying objects in space is challenging due to the divergence caused by the time delay. In this study, a divergence compensation approach is proposed for the stiffness-varying discrete contact. The dynamic response delay of the motion simulator and the force measurement delay are considered. For the force measurement delay, a phase lead based force compensation approach is used. For the dynamic response delay of the motion simulator, a response error based force compensation approach is used, where the compensation force is obtained from the real-time identified contact stiffness and real-time measured position response error. The dynamic response model of the motion simulator is not required. The simulations and experiments show that the simulation divergence can be compensated effectively and satisfactorily by using the proposed approach.

Delay in seeking medical help following Transient Ischemic Attack (TIA) or "mini-stroke": a qualitative study.

PubMed

Mc Sharry, Jennifer; Baxter, Alison; Wallace, Louise M; Kenton, Anthony; Turner, Andrew; French, David P

2014-01-01

Prompt treatment following Transient Ischemic Attack (TIA) can reduce the risk of subsequent stroke and disability. However, many patients delay in making contact with medical services. This study aimed to explore TIA patients' accounts of delay between symptom onset and contacting medical services including how decisions to contact services were made and the factors discussed in relation to delay. Twenty interviews were conducted with TIA patients in England. Using a previous systematic review as an initial framework, interview data were organised into categories of symptom recognition, presence of others and type of care sought. A thematic analysis was then conducted to explore descriptions of care-seeking relevant to each category. Delay in contacting medical services varied from less than an hour to eight days. Awareness of typical stroke symptoms could lead to urgent action when more severe TIA symptoms were present but could lead to delay when experienced symptoms were less severe. The role of friends and family varied widely from deciding on and enacting care-seeking decisions to simply providing transport to the GP practice. When family or friends played a greater role, and both made and enacted care-seeking decisions, delays were often shorter, even when patients themselves failed to identify symptoms. Healthcare professionals also impacted on patients' care-seeking with greater delays in seeking further care for the same episode described when patients perceived a lack of urgency during initial healthcare interactions. This study provides new information on patients' decisions to contact medical services following TIA and identifies overlapping factors that can lead to delay in receiving appropriate treatment. While recognition of symptoms may contribute to delay in contacting medical services, additional factors, including full responsibility being taken by others and initial healthcare interactions, can over-ride or undermine the importance of patients' own identification of TIA.

Delay in Seeking Medical Help following Transient Ischemic Attack (TIA) or “Mini-Stroke”: A Qualitative Study

PubMed Central

Mc Sharry, Jennifer; Baxter, Alison; Wallace, Louise M.; Kenton, Anthony; Turner, Andrew; French, David P.

2014-01-01

Background Prompt treatment following Transient Ischemic Attack (TIA) can reduce the risk of subsequent stroke and disability. However, many patients delay in making contact with medical services. This study aimed to explore TIA patients' accounts of delay between symptom onset and contacting medical services including how decisions to contact services were made and the factors discussed in relation to delay. Methods Twenty interviews were conducted with TIA patients in England. Using a previous systematic review as an initial framework, interview data were organised into categories of symptom recognition, presence of others and type of care sought. A thematic analysis was then conducted to explore descriptions of care-seeking relevant to each category. Results Delay in contacting medical services varied from less than an hour to eight days. Awareness of typical stroke symptoms could lead to urgent action when more severe TIA symptoms were present but could lead to delay when experienced symptoms were less severe. The role of friends and family varied widely from deciding on and enacting care-seeking decisions to simply providing transport to the GP practice. When family or friends played a greater role, and both made and enacted care-seeking decisions, delays were often shorter, even when patients themselves failed to identify symptoms. Healthcare professionals also impacted on patients' care-seeking with greater delays in seeking further care for the same episode described when patients perceived a lack of urgency during initial healthcare interactions. Conclusions This study provides new information on patients' decisions to contact medical services following TIA and identifies overlapping factors that can lead to delay in receiving appropriate treatment. While recognition of symptoms may contribute to delay in contacting medical services, additional factors, including full responsibility being taken by others and initial healthcare interactions, can over-ride or undermine the importance of patients' own identification of TIA. PMID:25137185

Occupational protein contact dermatitis from spices in a butcher: a new presentation of the mugwort-spice syndrome.

PubMed

Anliker, Mark David; Borelli, Siegfried; Wüthrich, Brunello

2002-02-01

Protein contact dermatitis to meat is well known in butchers; spices are another source of potential contact allergy and usually are not recognized. We present a first case of contact-dermatitis to spice mix in a 39-year-old-butcher. The patient underwent skin prick testing (SPT) with standard allergens (ALK) and different meat and spice extracts (Stallergènes), scratch-patch testing with spice mix containing glutamate, paprika and other spices. Specific serum-IgE was measured with CAP-FEIA. SPT only showed an immediate-type sensitization to mugwort (+ +), as well as different spices (paprika +, curry +, cumin +) and camomile (+ + +). Scratch-patch tests were negative for different meat, but strongly positive for spice mix (+ + +) after 30 min (wheal and flare) and (+ +) after 48 h (infiltration and vesiculation). Two healthy controls were tested negative for spice mix used from that patient (scratch-patch). Specific IgE was slightly elevated for paprika 0.47 kU/L (CAP class 1), anise 0.43 kU/L, curry 0.36 kU/L and mugwort 3.83 kU/L. Sx1 atopy-multiscreen was 3.8 kU/L due to a sensitization to mugwort alone. The tests performed demonstrate an IgE-mediated contact allergy to spices but also a delayed type allergy to spice mix as a manifestation of the mugwort-spice syndrome in this individual. When testing for occupational dermatitis in butchers, protein contact allergy to spices must also be taken into consideration.

Wind-Dragged Corolla Enhances Self-Pollination: A New Mechanism of Delayed Self-Pollination

PubMed Central

Qu, Rongming; Li, Xiaojie; Luo, Yibo; Dong, Ming; Xu, Huanli; Chen, Xuan; Dafni, Amots

2007-01-01

Background and Aims Delayed self-pollination is a mechanism that allows animal-pollinated plants to outcross while ensuring seed production in the absence of pollinators. This study aims to explore a new mechanism of delayed self-pollination facilitated by wind-driven corolla abscission in Incarvillea sinensis var. sinensis. Methods Floral morphology and development, and the process of delayed self-pollination were surveyed. Experiments dealing with pollinator and wind exclusion, pollination manipulations, and pollinator observations were conducted in the field. Key Results Delayed self-pollination occurs when the abscising corolla driven by wind drags the adherent epipetalous stamens, thus leading to contact of anthers with stigma in late anthesis. There is no dichogamy and self-incompatibility in this species. The significantly higher proportion of abscised corolla under natural conditions as compared with that in wind-excluding tents indicates the importance of wind in corolla abscission. When pollinators were excluded, corolla abscission significantly increased the number of pollen grains deposited on the stigma and, as a result, the fruit and seed set. Only half of the flowers in plots were visited by pollinators, and the fruit set of emasculated flowers was significantly lower than that of untreated flowers in open pollination. This species has a sensitive stigma, and its two open stigmatic lobes closed soon after being touched by a pollinator, but always reopened if no or only little pollen was deposited. Conclusions This delayed self-pollination, which involved the movement of floral parts, the active participation of the wind and sensitive stigma, is quite different from that reported previously. This mechanism provides reproductive assurance for this species. The sensitive stigma contributes to ensuring seed production and reducing the interference of selfing with outcrossing. The pollination pattern, which combines actions by bees with indirect participation by wind, is also a new addition to ambophily. PMID:17881336

Systemic Allergy to Corticosteroids: Clinical Features and Cross Reactivity.

PubMed

Barbaud, Annick; Waton, Julie

2016-01-01

Systemic hypersensitivity (HS) to corticosteroids (CS) is paradoxical but does exist. Some patients with a previous contact allergy to topical CS may develop a systemic contact dermatitis (SCD) while receiving CS orally or intravenously. However, a previous contact sensitization is not mandatory for developing a systemic HS to CS. Acute or delayed urticaria can occur in immediate HS. Immediate HS can be due to excipients, mainly carboxymethylcellulose or to CS themselves. Delayed reactions, mainly maculopapular rash and acute generalized exanthematous pustulosis can occur. Skin tests with systemic CS have to be standardized. It is necessary to determine if IDT with CS frequently induce skin atrophy or not and if such skin atrophy is transient by doing prospective studies using an standardized method and a limited injected volume (0.02 ml). Patch tests can be done in delayed HS, with readings at day 2, 4 and 7. In SCD, the Baeck's classification of CS in 3 chemical groups could explain cross reactivity between systemic CS. However, this classification is not applicable to explain cross-reactions between in systemic HS. According to the literature, 52/79 patients had a HS reaction to a group confirmed by a positive allergological investigations, but had a negative provocation test with another CS belonging to the same group. In case of non-severe cutaneous adverse reactions and when skin tests are negative, provocation tests have to be performed to find an alternative CS, even if it belongs to the same chemical group as those responsible for the initial reaction. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Studies of the quenching phenomenon in delayed contact hypersensitivity reactions.

PubMed

Basketter, D A; Allenby, C F

1991-09-01

Studies in guinea pig and man have shown that eugenol can quench non-specifically contact urticarial responses, whereas limonene seems largely ineffective. In a comprehensive series of studies, there was little evidence of quenching of delayed contact hypersensitivity reactions to cinnamic aldehyde or citral, including in 'pre-quenched' material supplied by a perfume/flavour company, and in a similar mixture prepared in this laboratory, in the guinea pig model. In addition, there was no evidence of the quenching by eugenol of allergic reactions to cinnamic aldehyde in a panel of human subjects with a proven history of cinnamic-aldehyde-induced allergic contact dermatitis. Overall, the results lend little credibility to earlier literature reports of quenching phenomena in delayed contact hypersensitivity responses.

Predictors of Late Reperfusion in STEMI Patients Undergoing Primary Angioplasty. Impact of the Place of First Medical Contact.

PubMed

Carol Ruiz, Antoni; Masip Utset, Josep; Ariza Solé, Albert

2017-03-01

The benefit of primary angioplasty may be reduced if there are delays to reperfusion. Identification of the variables associated with these delays could improve health care. Analysis of the Codi Infart registry of Catalonia and of the time to angioplasty depending on the place of first medical contact. In 3832 patients analyzed, first medical contact took place in primary care centers in 18% and in hospitals without a catheterization laboratory in 37%. Delays were longer in these 2 groups than in patients attended by the outpatient emergency medical system or by hospitals with a catheterization laboratory (P < .0001, results in median): first medical contact to reperfusion indication time was 42minutes in both (overall 35minutes); first medical contact to artery opening time was 131 and 143minutes, respectively (overall 121minutes); total ischemia time was 230 and 260minutes (overall 215minutes). First medical contact to artery opening time > 120minutes was strongly associated with first medical contact in a center without a catheterization laboratory (OR, 4.96; 95% confidence interval, 4.14-5.93), and other factors such as age, previous coronary surgery, first medical contact during evening hours, nondiagnostic electrocardiogram, and Killip class ≥ III. Mortality at 30 days and 1 year was 5.6% and 8.7% and was independently associated with age, longer delay to angioplasty, Killip class ≥ II, and first medical contact in a center with a catheterization laboratory. In more than 50% of patients requiring primary angioplasty, the first medical contact occurs in centers without a catheterization laboratory, which is an important predictor of delay from diagnosis to artery opening. Copyright © 2016 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

STUDIES ON THE SENSITIZATION OF ANIMALS WITH SIMPLE CHEMICAL COMPOUNDS

PubMed Central

Maguire, Henry C.; Chase, Merrill W.

1972-01-01

A method of establishing regular and intense sensitivity to picric acid is described, based upon an initial sensitization by a "split-adjuvant" technique in which the intradermal injection of mycobacteria in paraffin oil precedes or follows the administration of allergen to the same sites. When subsequent contact applications of picric acid are later made, the degree of sensitivity rises in steps such that reactivity occurs in tests made with low concentrations of picric acid, in the range of 0.06–0.006% but varying somewhat from one experiment to another. This heightening of picric acid reactivity represents an anamnestic response in the area of delayed hypersensitivity. The characteristics of contact reactions to the weak allergen, picric acid, differ from those encountered with covalently binding haptens, PCI and DNCB. A slow evolution from an initial micropapular reaction to full reaction requires about 3 days, leading often to a micaceous scale, with histological evidence of vesiculation even while the reaction is still feeble, and to an infiltrate containing a significant number of polymorphonuclear leukocytes. Substitution of an emulsion of picric acid in complete Freund's adjuvant as a priming experience proved to be much less efficient. The split-adjuvant technique offers a general plan for sensitizing with weak allergens. Indeed, technically, sensitization can be acquired even when, for priming, the allergen is applied topically over intradermal depots of mycobacteria in paraffin oil. Compatibility between sensitizer and adjuvant is not required. PMID:5060294

Footwear contact dermatitis from dimethyl fumarate.

PubMed

Švecová, Danka; Šimaljakova, Maria; Doležalová, Anna

2013-07-01

Dimethyl fumarate (DMF) is an effective inhibitor of mold growth. In very low concentrations, DMF is a potent sensitizer that can cause severe allergic contact dermatitis (ACD). It has been identified as the agent responsible for furniture contact dermatitis in Europe. The aim of this study was to evaluate patients in Slovakia with footwear ACD associated with DMF, with regard to clinical manifestations, patch test results, and results of chemical analysis of their footwear. Nine patients with suspected footwear contact dermatitis underwent patch testing with the following allergens: samples of their own footwear, commercial DMF, the European baseline, shoe screening, textile and leather dye screening, and industrial biocides series. The results were recorded according to international guidelines. The content of DMF in footwear and anti-mold sachets was analyzed using gas chromatography and mass spectrometry. Acute ACD was observed in nine Caucasian female patients. All patients developed delayed sensitization, as demonstrated by positive patch testing using textile footwear lining. Seven patients were patch tested with 0.1% DMF, and all seven were positive. Chemical analysis of available footwear showed that DMF was present in very high concentrations (25-80 mg/Kg). Dimethyl fumarate is a new footwear allergen and was responsible for severe ACD in our patients. To avoid an increase in the number of cases, the already approved European preventive measures should be accepted and commonly employed. © 2013 The International Society of Dermatology.

The fragility of intergroup relations: divergent effects of delayed audiovisual feedback in intergroup and intragroup interaction.

PubMed

Pearson, Adam R; West, Tessa V; Dovidio, John F; Powers, Stacie Renfro; Buck, Ross; Henning, Robert

2008-12-01

Intergroup interactions between racial or ethnic majority and minority groups are often stressful for members of both groups; however, the dynamic processes that promote or alleviate tension in intergroup interaction remain poorly understood. Here we identify a behavioral mechanism-response delay-that can uniquely contribute to anxiety and promote disengagement from intergroup contact. Minimally acquainted White, Black, and Latino participants engaged in intergroup or intragroup dyadic conversation either in real time or with a subtle temporal disruption (1-s delay) in audiovisual feedback. Whereas intergroup dyads reported greater anxiety and less interest in contact after engaging in delayed conversation than after engaging in real-time conversation, intragroup dyads reported less anxiety in the delay condition than they did after interacting in real time. These findings have theoretical and practical implications for understanding intergroup communication and social dynamics and for promoting positive intergroup contact.

Bitter-sensitive gustatory receptor neuron responds to chemically diverse insect repellents in the common malaria mosquito Anopheles quadrimaculatus

NASA Astrophysics Data System (ADS)

Sparks, Jackson T.; Dickens, Joseph C.

2016-06-01

Female mosquitoes feed on blood from animal hosts to obtain nutritional resources used for egg production. These contacts facilitate the spread of harmful human diseases. Chemical repellents are used to disrupt mosquito host-seeking and blood-feeding behaviors; however, little is known about the gustatory sensitivity of mosquitoes to known repellents. Here, we recorded electrical responses from gustatory receptor neurons (GRNs) housed within the labellar sensilla of female Anopheles quadrimaculatus to N,N-diethyl-3-methylbenzamide (DEET), picaridin, IR3535, 2-undecanone, p-menthane-3,8-diol, geraniol, trans-2-hexen-1-ol, quinine, and quinidine. A bitter-sensitive GRN responded to all tested repellents and quinine, a known feeding deterrent. Responses of the bitter-sensitive neuron to quinine and an isomer, quinidine, did not differ. Delayed bursts of electrical activity were observed in response to continuous stimulation with synthetic repellents at high concentrations. Electrophysiological recordings from bitter-sensitive GRNs associated with mosquito gustatory sensilla represent a convenient model to evaluate candidate repellents.

Bitter-sensitive gustatory receptor neuron responds to chemically diverse insect repellents in the common malaria mosquito Anopheles quadrimaculatus.

PubMed

Sparks, Jackson T; Dickens, Joseph C

2016-06-01

Female mosquitoes feed on blood from animal hosts to obtain nutritional resources used for egg production. These contacts facilitate the spread of harmful human diseases. Chemical repellents are used to disrupt mosquito host-seeking and blood-feeding behaviors; however, little is known about the gustatory sensitivity of mosquitoes to known repellents. Here, we recorded electrical responses from gustatory receptor neurons (GRNs) housed within the labellar sensilla of female Anopheles quadrimaculatus to N,N-diethyl-3-methylbenzamide (DEET), picaridin, IR3535, 2-undecanone, p-menthane-3,8-diol, geraniol, trans-2-hexen-1-ol, quinine, and quinidine. A bitter-sensitive GRN responded to all tested repellents and quinine, a known feeding deterrent. Responses of the bitter-sensitive neuron to quinine and an isomer, quinidine, did not differ. Delayed bursts of electrical activity were observed in response to continuous stimulation with synthetic repellents at high concentrations. Electrophysiological recordings from bitter-sensitive GRNs associated with mosquito gustatory sensilla represent a convenient model to evaluate candidate repellents.

Dynamic Resource Allocation and Access Class Barring Scheme for Delay-Sensitive Devices in Machine to Machine (M2M) Communications.

PubMed

Li, Ning; Cao, Chao; Wang, Cong

2017-06-15

Supporting simultaneous access of machine-type devices is a critical challenge in machine-to-machine (M2M) communications. In this paper, we propose an optimal scheme to dynamically adjust the Access Class Barring (ACB) factor and the number of random access channel (RACH) resources for clustered machine-to-machine (M2M) communications, in which Delay-Sensitive (DS) devices coexist with Delay-Tolerant (DT) ones. In M2M communications, since delay-sensitive devices share random access resources with delay-tolerant devices, reducing the resources consumed by delay-sensitive devices means that there will be more resources available to delay-tolerant ones. Our goal is to optimize the random access scheme, which can not only satisfy the requirements of delay-sensitive devices, but also take the communication quality of delay-tolerant ones into consideration. We discuss this problem from the perspective of delay-sensitive services by adjusting the resource allocation and ACB scheme for these devices dynamically. Simulation results show that our proposed scheme realizes good performance in satisfying the delay-sensitive services as well as increasing the utilization rate of the random access resources allocated to them.

A novel in-vitro method for assessing contact lens surface dewetting: Non-invasive keratograph dry-up time (NIK-DUT).

PubMed

Marx, Sebastian; Sickenberger, Wolfgang

2017-12-01

This study was designed to develop a novel technique called non-invasive keratograph dry-up time (NIK-DUT), which used an adapted corneal topographer, to analyse in-vitro contact lens surface dewetting and the effects of combinations of lenses and lens care solutions on dewetting. Variables were assessed to optimise sensitivity and reproducibility. To validate the method, in-vitro dewetting of silicone hydrogel contact lenses (balafilcon A, comfilcon A, lotrafilcon A, lotrafilcon B and senofilcon A) was tested. All lens types were soaked in OPTI-FREE ® PureMoist ® Multipurpose Disinfecting Solution (OFPM) and Sensitive Eyes ® Saline Solution. The mean NIK-DUT, defined as drying of 25% of the placido ring measurement segments (NIK-DUT_S25), was calculated for each lens/lens solution combination and a visual map constructed representing the time and location of the dry-up event. Optimal conditions for NIK-DUT measurement included mounting onto a glass stage with a surface geometry of r=8.5mm, e=0, and measuring with high intensity red or white illumination. This method detected significant differences in contact lens dewetting with different lens soaking solutions. NIK-DUT_S25 for all lenses was longer when pre-soaked in OFPM versus saline. Visual analysis showed that dewetting of contact lenses was not uniform across surfaces and differed between test solutions. NIK-DUT is suitable for detecting differences in dewetting among various contact lenses and lens-care combinations. NIK-DUT can quantify the dewetting of large areas of lens surfaces with little subjective influence. Lens care solutions containing surface-active wetting agents were found to delay surface dewetting of silicone hydrogel lenses. Copyright © 2017. Published by Elsevier Ltd.

Delay From First Medical Contact to Primary PCI and All‐Cause Mortality: A Nationwide Study of Patients With ST‐Elevation Myocardial Infarction

PubMed Central

Koul, Sasha; Andell, Pontus; Martinsson, Andreas; Gustav Smith, J.; van der Pals, Jesper; Scherstén, Fredrik; Jernberg, Tomas; Lagerqvist, Bo; Erlinge, David

2014-01-01

Background Early reperfusion in the setting of an ST‐elevation myocardial infarction (STEMI) is of utmost importance. However, the effects of early versus late reperfusion in this patient group undergoing primary percutaneous coronary intervention (PCI) have so far been inconsistent in previous studies. The purpose of this study was to evaluate in a nationwide cohort the effects of delay from first medical contact to PCI (first medical contact [FMC]‐to‐PCI) and secondarily delay from symptom‐to‐PCI on clinical outcomes. Methods and Results Using the national Swedish Coronary Angiography and Angioplasty Register (SCAAR) registry, STEMI patients undergoing primary PCI between the years 2003 and 2008 were screened for. A total of 13 790 patients were included in the FMC‐to‐PCI analysis and 11 489 patients were included in the symptom‐to‐PCI analyses. Unadjusted as well as multivariable analyses showed an overall significant association between increasing FMC‐to‐PCI delay and 1‐year mortality. A statistically significant increase in mortality was noted at FMC‐to‐PCI delays exceeding 1 hour in an incremental fashion. FMC‐to‐PCI delays in excess of 1 hour were also significantly associated with an increase in severe left ventricular dysfunction at discharge. An overall significant association between increasing symptom‐to‐PCI delays and 1‐year mortality was noted. However, when stratified into time delay cohorts, no symptom‐to‐PCI delay except for the highest time delay showed a statistically significant association with increased mortality. Conclusions Delays in FMC‐to‐PCI were strongly associated with increased mortality already at delays of more than 1 hour, possibly through an increase in severe heart failure. A goal of FMC‐to‐PCI of less than 1 hour might save patient lives. PMID:24595190

The noninvasive mouse ear swelling assay. I. Refinements for detecting weak contact sensitizers.

PubMed

Thorne, P S; Hawk, C; Kaliszewski, S D; Guiney, P D

1991-11-01

The noninvasive mouse ear swelling assay (MESA) is a model for delayed-type hypersensitivity that holds promise as a testing protocol for allergic contact dermatitis (ACD). The MESA employs only topical sensitization on the abdomen and does not use injections, adjuvants, anesthesia, occlusion, or disruption of the stratum corneum. Five days after induction, the ears are challenged topically and ear swelling measurements taken at 24, 48, and 72 hr indicate the extent of ACD. In this study, refinements of the assay were explored in BALB/cBy mice using dinitrofluorobenzene (DNFB) and dinitrochlorobenzene (DNCB). A complete dose-response curve was developed for DNFB and the dose which sensitized half the mice in a group (SD50, 0.001%, w/v) was used to test noninvasive enhancement protocols. Several triple-dose protocols tested produced no increase in responsiveness and daily dosing showed a trend toward tolerance induction yielding 20% positive responses. Dietary vitamin A supplementation produced a dramatic enhancement of the responses: ear thickness increase was doubled and the SD50 sensitized 94 to 100% of the mice in the vitamin A groups. We conclude that the MESA allowed identification of ACD potency for known sensitizers at very low concentrations which do not produce ACD with other techniques. The importance of dose-response studies for avoiding the high-dose reduced-response region was also shown. Based on the observation that the vitamin A-augmented MESA was considerably more sensitive than with regular feed, a companion study (P.S. Thorne. C. Hawk, S.D. Kaliszewski, P.D. Guiney, Fundam. Appl. Tox. 17, 807-820, 1991) presents tests of the enhancements to the MESA developed in this work, using weak sensitizers and complex mixtures.

Parametric Sensitivity Analysis of Oscillatory Delay Systems with an Application to Gene Regulation.

PubMed

Ingalls, Brian; Mincheva, Maya; Roussel, Marc R

2017-07-01

A parametric sensitivity analysis for periodic solutions of delay-differential equations is developed. Because phase shifts cause the sensitivity coefficients of a periodic orbit to diverge, we focus on sensitivities of the extrema, from which amplitude sensitivities are computed, and of the period. Delay-differential equations are often used to model gene expression networks. In these models, the parametric sensitivities of a particular genotype define the local geometry of the evolutionary landscape. Thus, sensitivities can be used to investigate directions of gradual evolutionary change. An oscillatory protein synthesis model whose properties are modulated by RNA interference is used as an example. This model consists of a set of coupled delay-differential equations involving three delays. Sensitivity analyses are carried out at several operating points. Comments on the evolutionary implications of the results are offered.

Allergic contact dermatitis caused by acrylic-based medical dressings and adhesives.

PubMed

Mestach, Lien; Huygens, Sara; Goossens, An; Gilissen, Liesbeth

2018-06-11

Acrylates and methacrylates are acrylic resin monomers that are known to induce skin sensitization as a result of their presence in different materials, such as nail cosmetics, dental materials, printing inks, and adhesives. Allergic contact dermatitis resulting from the use of modern wound dressings containing them has only rarely been reported. To describe 2 patients who developed allergic contact dermatitis caused by acrylic-based modern medical dressings and/or adhesives. The medical charts of patients observed since 1990 were retrospectively reviewed for (meth)acrylate allergy resulting from contact with such materials, and their demographic characteristics and patch test results were analysed. Two patients were observed in 2014 and 2016 who had presented with positive patch test reactions to several acrylic-based dressings and/or adhesive materials, and to several (meth)acrylates, that is, hydroxyethyl acrylate, hydroxyethyl methacrylate, ethyleneglycol dimethacrylate, bisphenol A-glycidyl methacrylate/epoxy-acrylate, urethane diacrylate, and/or penta-erythritol acrylate. Allergic contact dermatitis needs to be considered in patients with eczematous reactions or delayed healing following the use of acrylic-based modern dressings or adhesives. However, identification of the culprit allergen is hampered by poor cooperation from the producers, so adequate labelling of medical devices is an urgent necessity. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Protein contact dermatitis: allergens, pathogenesis, and management.

PubMed

Levin, Cheryl; Warshaw, Erin

2008-01-01

Protein contact dermatitis is an allergic skin reaction induced principally by proteins of either animal or plant origin. The clinical presentation is that of a chronic dermatitis, and it is often difficult to differentiate between allergic contact dermatitis and other eczematous dermatoses. One distinguishing clinical feature is that acute flares of pruritus, urticaria, edema, or vesiculation are noted minutes after contact with the causative substances. Additionally, the patch-test result is typically negative, and the scratch- or prick-test result is positive. The pathogenesis of protein contact dermatitis is unclear but may involve a type I (immunoglobulin E [IgE], immediate) hypersensitivity reaction, type IV (cell-mediated delayed) hypersensitivity reaction, and/or a delayed reaction due to IgE-bearing Langerhans' cells. Management involves avoidance of the allergen.

Cinnamic aldehyde: a survey of consumer patch-test sensitization.

PubMed

Danneman, P J; Booman, K A; Dorsky, J; Kohrman, K A; Rothenstein, A S; Sedlak, R I; Steltenkamp, R J; Thompson, G R

1983-12-01

The potential for cinnamic aldehyde, an important fragrance and flavour ingredient, to induce or to elicit delayed contact hypersensitivity reactions in man was evaluated by analysing patch-test data. Results of studies involving a total of 4117 patch tests on various consumer products and fragrance blends containing cinnamic aldehyde and on the material itself were collected from fragrance and formulator companies. The data indicate that cinnamic aldehyde contained in consumer products and fragrance blends at concentrations up to 6 X 10(-1)%, and patch-tested at concentrations up to 8 X 10(-3)%, has no detectable potential to induce hypersensitivity. Cinnamic aldehyde when tested alone induced a dose-related hypersensitivity response. According to published reports, cinnamic aldehyde elicited positive delayed hypersensitivity responses in dermatitic patients. However, results of the current survey show that when cinnamic aldehyde was tested alone or as part of a mixture in subjects in the general population, no pre-existing hypersensitivity reactions to the fragrance material were observed in any of the 4117 patch tests which constituted the survey. Cinnamic aldehyde at the concentrations contained in consumer products and fragrances, has a very low potential to induce hypersensitivity ('induced' reactions) or to elicit sensitization reactions ('elicited' reactions) in the general population.

Different CT perfusion algorithms in the detection of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage.

PubMed

Cremers, Charlotte H P; Dankbaar, Jan Willem; Vergouwen, Mervyn D I; Vos, Pieter C; Bennink, Edwin; Rinkel, Gabriel J E; Velthuis, Birgitta K; van der Schaaf, Irene C

2015-05-01

Tracer delay-sensitive perfusion algorithms in CT perfusion (CTP) result in an overestimation of the extent of ischemia in thromboembolic stroke. In diagnosing delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH), delayed arrival of contrast due to vasospasm may also overestimate the extent of ischemia. We investigated the diagnostic accuracy of tracer delay-sensitive and tracer delay-insensitive algorithms for detecting DCI. From a prospectively collected series of aSAH patients admitted between 2007-2011, we included patients with any clinical deterioration other than rebleeding within 21 days after SAH who underwent NCCT/CTP/CTA imaging. Causes of clinical deterioration were categorized into DCI and no DCI. CTP maps were calculated with tracer delay-sensitive and tracer delay-insensitive algorithms and were visually assessed for the presence of perfusion deficits by two independent observers with different levels of experience. The diagnostic value of both algorithms was calculated for both observers. Seventy-one patients were included. For the experienced observer, the positive predictive values (PPVs) were 0.67 for the delay-sensitive and 0.66 for the delay-insensitive algorithm, and the negative predictive values (NPVs) were 0.73 and 0.74. For the less experienced observer, PPVs were 0.60 for both algorithms, and NPVs were 0.66 for the delay-sensitive and 0.63 for the delay-insensitive algorithm. Test characteristics are comparable for tracer delay-sensitive and tracer delay-insensitive algorithms for the visual assessment of CTP in diagnosing DCI. This indicates that both algorithms can be used for this purpose.

Effect of healing time on bone-implant contact of orthodontic micro-implants: a histologic study.

PubMed

Ramazanzadeh, Barat Ali; Fatemi, Kazem; Dehghani, Mahboobe; Mohtasham, Nooshin; Jahanbin, Arezoo; Sadeghian, Hamed

2014-01-01

Objectives. This study aimed to evaluate the effect of immediate and delayed loading of orthodontic micro-implants on bone-implant contact. Materials and Methods. Sixty four micro-implants were implanted in dog's jaw bone. The micro-implants were divided into loaded and unloaded (control) groups. The control group had two subgroups: four and eight weeks being implanted. The loaded group had two subgroups of immediate loading and delayed (after four weeks healing) loading. Loaded samples were subjected to 200g load for four weeks. After sacrificing the animals micro-implants and surrounding tissues were observed histologically. Bone-implant contact ratios (BIC) were calculated and different groups' results were compared by three-way ANOVA. Results. Mean survival rate was 96.7% in general. Survival rates were 96.7%, 94.4% and 100% for control, immediate and delayed loaded groups, respectively. BIC values were not significantly different in loaded and control groups, immediate and delayed loading groups, and pressure and tension sides. Mandibular micro-implants had significantly higher BIC than maxillary ones in immediate loading, 4-weeks control, and 8-weeks control groups (P = 0.021, P = 0.009, P = 0.003, resp.). Conclusion Immediate or delayed loading of micro-implants in dog did not cause significant difference in Bone-implant contact which could be concluded that healing time had not significant effect on micro-implant stability.

Effect of Healing Time on Bone-Implant Contact of Orthodontic Micro-Implants: A Histologic Study

PubMed Central

Ramazanzadeh, Barat Ali; Fatemi, Kazem; Dehghani, Mahboobe; Mohtasham, Nooshin; Jahanbin, Arezoo; Sadeghian, Hamed

2014-01-01

Objectives. This study aimed to evaluate the effect of immediate and delayed loading of orthodontic micro-implants on bone-implant contact. Materials and Methods. Sixty four micro-implants were implanted in dog's jaw bone. The micro-implants were divided into loaded and unloaded (control) groups. The control group had two subgroups: four and eight weeks being implanted. The loaded group had two subgroups of immediate loading and delayed (after four weeks healing) loading. Loaded samples were subjected to 200g load for four weeks. After sacrificing the animals micro-implants and surrounding tissues were observed histologically. Bone-implant contact ratios (BIC) were calculated and different groups' results were compared by three-way ANOVA. Results. Mean survival rate was 96.7% in general. Survival rates were 96.7%, 94.4% and 100% for control, immediate and delayed loaded groups, respectively. BIC values were not significantly different in loaded and control groups, immediate and delayed loading groups, and pressure and tension sides. Mandibular micro-implants had significantly higher BIC than maxillary ones in immediate loading, 4-weeks control, and 8-weeks control groups (P = 0.021, P = 0.009, P = 0.003, resp.). Conclusion Immediate or delayed loading of micro-implants in dog did not cause significant difference in Bone-implant contact which could be concluded that healing time had not significant effect on micro-implant stability. PMID:25006463

Effects of time delay and pitch control sensitivity in the flared landing

NASA Technical Reports Server (NTRS)

Berthe, C. J.; Chalk, C. R.; Wingarten, N. C.; Grantham, W.

1986-01-01

Between December 1985 and January 1986, a flared landing program was conducted, using the USAF Total In-Flight simulator airplane, to examine time delay effects in a formal manner. Results show that as pitch sensitivity is increased, tolerance to time delay decreases. With the proper selection of pitch sensitivity, Level I performance was maintained with time delays ranging from 150 milliseconds to greater than 300 milliseconds. With higher sensitivity, configurations with Level I performance at 150 milliseconds degraded to level 2 at 200 milliseconds. When metrics of time delay and pitch sensitivity effects are applied to enhance previously developed predictive criteria, the result is an improved prediction technique which accounts for significant closed loop items.

Hybrid Smith predictor and phase lead based divergence compensation for hardware-in-the-loop contact simulation with measurement delay

NASA Astrophysics Data System (ADS)

Qi, Chenkun; Gao, Feng; Zhao, Xianchao; Wang, Qian; Ren, Anye

2018-06-01

On the ground the hardware-in-the-loop (HIL) simulation is a good approach to test the contact dynamics of spacecraft docking process in space. Unfortunately, due to the time delay in the system the HIL contact simulation becomes divergent. However, the traditional first-order phase lead compensation approach still result in a small divergence for the pure time delay. The serial Smith predictor and phase lead compensation approach proposed by the authors recently will lead to an over-compensation and an obvious convergence. In this study, a hybrid Smith predictor and phase lead compensation approach is proposed. The hybrid Smith predictor and phase lead compensation can achieve a higher simulation fidelity with a little convergence. The phase angle of the compensator is analyzed and the stability condition of the HIL simulation system is given. The effectiveness of the proposed compensation approach is tested by simulations on an undamped elastic contact process.

Polysensitization and individual susceptibility to allergic contact dermatitis.

PubMed

Gosnell, Amy L; Schmotzer, Brian; Nedorost, Susan T

2015-01-01

Patients with allergic contact dermatitis to 1 antigen have been shown to be at increased risk of developing delayed type hypersensitivity reactions to additional antigens. Both environmental and genetic factors likely influence the risk of sensitization. The aim of this study was to determine whether polysensitization occurs at a higher frequency than would be expected based on chance and whether polysensitization occurs more often in subsets of patients with hand involvement and atopic dermatitis. From a database of patch test results from a single practitioner, the probability of having positive reactions to 3 or more unrelated allergens was calculated under the assumption that positive reactions are independent and compared with the observed proportion having positive reactions to 3 or more unrelated allergens. The analysis was repeated excluding patients with leg involvement as a proxy for venous insufficiency dermatitis. The proportion of patients from the polysensitized and nonpolysensitized cohorts with either hand involvement or a history of atopic dermatitis was also calculated. Polysensitization occurs more often than expected based on chance. Polysensitized patients were more likely to have hand dermatitis. Atopic dermatitis was not significantly associated with polysensitization in this analysis. Polysensitized individuals may represent a phenotype with increased genetic susceptibility to sensitization.

Impulsivity in spontaneously hypertensive rats: Within-subjects comparison of sensitivity to delay and to amount of reinforcement.

PubMed

Orduña, Vladimir; Mercado, Eduardo

2017-06-15

Previous research has shown that spontaneously hypertensive rats (SHR) display higher levels of impulsive choice behavior, which is accompanied by a higher sensitivity to the delay of reinforcement, and by a normal sensitivity to the amount of reinforcement. Because those results were based on three different samples of subjects, in the present report we evaluated these three processes in the same individuals. SHR and WIS rats were exposed to concurrent-chains schedules in which the terminal links were manipulated to assess impulsivity, sensitivity to delay, and sensitivity to amount. For exploring impulsivity, a terminal link was associated with a small reinforcer (1 pellet) delivered after a short delay (2s) while the other terminal link was associated with a larger reinforcer (4 pellets) delivered after a longer delay (28s). For assessing sensitivity to delay, both alternatives delivered the same amount of reinforcement (1 pellet) and the only difference between them was in the delay before reinforcement delivery (2s vs 28s). For assessing sensitivity to amount, both alternatives were associated with the same delay (15s), but the alternatives differed in the amount of reinforcement (1 vs 4 pellets). In addition to replicating previously observed effects within-subjects, we were interested in analyzing different aspects of the regularity of rats' actions in the choice task. The results confirmed that previous findings were not a consequence of between-group differences: SHR were more impulsive and more sensitive to delay, while their sensitivity to amount was normal. Analyses of response regularity indicated that SHR subjects were more periodic in their responses to levers and in their feeder entries, had a higher number of short-duration bouts of responding, and made a substantially higher number of switches between the alternatives. We discuss the potential implications of these findings for the possible behavioral mechanisms driving the increased sensitivity to delay in SHR. Copyright © 2017 Elsevier B.V. All rights reserved.

Five-year evolution of reperfusion strategies and early mortality in patients with ST-segment elevation myocardial infarction in France.

PubMed

El Khoury, Carlos; Bochaton, Thomas; Flocard, Elodie; Serre, Patrice; Tomasevic, Danka; Mewton, Nathan; Bonnefoy-Cudraz, Eric

2017-10-01

To assess 5-year evolutions in reperfusion strategies and early mortality in patients with ST-segment elevation myocardial infarction. Using data from the French RESCUe network, we studied patients with ST-segment elevation myocardial infarction treated in mobile intensive care units between 2009 and 2013. Among 2418 patients (median age 62 years; 78.5% male), 2119 (87.6%) underwent primary percutaneous coronary intervention and 299 (12.4%) pre-hospital thrombolysis (94.0% of whom went on to undergo percutaneous coronary intervention). Use of primary percutaneous coronary intervention increased from 78.4% in 2009 to 95.9% in 2013 ( P trend <0.001). Median delays included: first medical contact to percutaneous coronary intervention centre 48 minutes; first medical contact to balloon inflation 94 minutes; and percutaneous coronary intervention centre to balloon inflation 43 minutes. Times from symptom onset to first medical contact and first medical contact to thrombolysis remained stable during 2009-2013, but times from symptom onset to first balloon inflation, and first medical contact to percutaneous coronary intervention centre to first balloon inflation decreased ( P<0.001). Among patients with known timings, 2146 (89.2%) had a first medical contact to percutaneous coronary intervention centre delay ⩽90 minutes, while 260 (10.8%) had a longer delay, with no significant variation over time. Primary percutaneous coronary intervention use increased over time in both delay groups, but was consistently higher in the ⩽90 versus >90 minutes delay group (83.0% in 2009 to 97.7% in 2013; P trend <0.001 versus 34.1% in 2009 to 79.2% in 2013; P trend <0.001). In-hospital (4-6%) and 30-day (6-8%) mortalities remained stable from 2009 to 2013. In the RESCUe network, the use of primary percutaneous coronary intervention increased from 2009 to 2013, in line with guidelines, but there was no evolution in early mortality.

Contact tracing and antiviral prophylaxis in the early stages of a pandemic: the probability of a major outbreak.

PubMed

Ross, Joshua V; Black, Andrew J

2015-09-01

Antiviral prophylaxis forms a significant component of health management plans for many countries around the world. A number of studies have shown that the delays typically encountered in distributing these antivirals to households, following the first infectious case, can result in their efficacy being severely reduced. Here, we investigate the use of contact tracing as a method to reduce the delays and hence mitigate the reduction in efficacy of antivirals. We assess the usefulness of contact tracing in terms of the probability of a major outbreak. It is found, with parameter distributions appropriate to the 2009 H1N1 pandemic and distributions reflecting commonly experienced delays, that standard contact tracing renders an outbreak impossible approximately one in five times compared with approximately one in ten times in its absence. A contact-tracing efficiency of 50% would see further improvements with an outbreak being impossible approximately one in four times, and a reduction of the median probability of a major outbreak from 0.41 to below 0.27. © The authors 2014. Published by Oxford University Press on behalf of the Institute of Mathematics and its Applications. All rights reserved.

Intrinsic delay of permeable base transistor

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

Chen, Wenchao; Guo, Jing; So, Franky

2014-07-28

Permeable base transistors (PBTs) fabricated by vacuum deposition or solution process have the advantages of easy fabrication and low power operation and are a promising device structure for flexible electronics. Intrinsic delay of PBT, which characterizes the speed of the transistor, is investigated by solving the three-dimensional Poisson equation and drift-diffusion equation self-consistently using finite element method. Decreasing the emitter thickness lowers the intrinsic delay by improving on-current, and a thinner base is also preferred for low intrinsic delay because of fewer carriers in the base region at off-state. The intrinsic delay exponentially decreases as the emitter contact Schottky barriermore » height decreases, and it linearly depends on the carrier mobility. With an optimized emitter contact barrier height and device geometry, a sub-nano-second intrinsic delay can be achieved with a carrier mobility of ∼10 cm{sup 2}/V/s obtainable in solution processed indium gallium zinc oxide, which indicates the potential of solution processed PBTs for GHz operations.« less

Evaluation of electrical propagation delay with cardiomyocytes by photosensitization reaction in vitro

NASA Astrophysics Data System (ADS)

Doi, Marika; Ogawa, Emiyu; Arai, Tsunenori

2017-02-01

In order to study cardiomyocyte electrical conduction damage by a photosensitization reaction (PR) mostly comes from outside of the cells in a few minutes after the PR, we studied propagation delay of contact action potential with cardiomyocyte by the PR. To determine appropriate PR condition for tachyarrhythmia ablation, a precise electrophysiological experiment in vitro has been preferable. We measured the contact action potential using a microelectrode array system of which information may be correct than conventional Ca2+ measurement. We investigated the propagation delays of an evoked potential to evaluate the electrical conduction damage by the PR. Rat cardiomyocytes were cultivated for 5-7 days on a dish with which 64 electrodes were patterned, in an incubator controlled to 37°C, 5% CO2. The following conditions were used for the PR: 40 μg/ml talapordfin sodium and 290 mW/cm2, 40-78 J/cm2 for an irradiation. A 2D map was obtained to visualize the propagation delays of the evoked potential. The propagation speed, which was calculated based on the measured propagation delays, was decreased by about 30-50% on average of all electrodes after the PR. Therefore, we think 2D propagation delays measurement of the evoked potential with contact action potential measuring system might be available to evaluate the acute electrical conduction damage of cardiomyocyte by the PR.

Role of ionotropic glutamate receptors in delay and probability discounting in the rat.

PubMed

Yates, Justin R; Batten, Seth R; Bardo, Michael T; Beckmann, Joshua S

2015-04-01

Discounting of delayed and probabilistic reinforcement is linked to increased drug use and pathological gambling. Understanding the neurobiology of discounting is important for designing treatments for these disorders. Glutamate is considered to be involved in addiction-like behaviors; however, the role of ionotropic glutamate receptors (iGluRs) in discounting remains unclear. The current study examined the effects of N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor blockade on performance in delay and probability discounting tasks. Following training in either delay or probability discounting, rats (n = 12, each task) received pretreatments of the NMDA receptor antagonists MK-801 (0, 0.01, 0.03, 0.1, or 0.3 mg/kg, s.c.) or ketamine (0, 1.0, 5.0, or 10.0 mg/kg, i.p.), as well as the AMPA receptor antagonist CNQX (0, 1.0, 3.0, or 5.6 mg/kg, i.p.). Hyperbolic discounting functions were used to estimate sensitivity to delayed/probabilistic reinforcement and sensitivity to reinforcer amount. An intermediate dose of MK-801 (0.03 mg/kg) decreased sensitivity to both delayed and probabilistic reinforcement. In contrast, ketamine did not affect the rate of discounting in either task but decreased sensitivity to reinforcer amount. CNQX did not alter sensitivity to reinforcer amount or delayed/probabilistic reinforcement. These results show that blockade of NMDA receptors, but not AMPA receptors, decreases sensitivity to delayed/probabilistic reinforcement (MK-801) and sensitivity to reinforcer amount (ketamine). The differential effects of MK-801 and ketamine demonstrate that sensitivities to delayed/probabilistic reinforcement and reinforcer amount are pharmacologically dissociable.

Theoretical foundations for traditional and generalized sensitivity functions for nonlinear delay differential equations.

PubMed

Banks, H Thomas; Robbins, Danielle; Sutton, Karyn L

2013-01-01

In this paper we present new results for differentiability of delay systems with respect to initial conditions and delays. After motivating our results with a wide range of delay examples arising in biology applications, we further note the need for sensitivity functions (both traditional and generalized sensitivity functions), especially in control and estimation problems. We summarize general existence and uniqueness results before turning to our main results on differentiation with respect to delays, etc. Finally we discuss use of our results in the context of estimation problems.

Airborne allergic contact dermatitis caused by isothiazolinones in water-based paints: a retrospective study of 44 cases.

PubMed

Amsler, Emmanuelle; Aerts, Olivier; Raison-Peyron, Nadia; Debons, Michèle; Milpied, Brigitte; Giordano-Labadie, Françoise; Waton, Julie; Ferrier-Le Bouëdec, Marie C; Lartigau, Isabelle; Pecquet, Catherine; Assier, Haudrey; Avenel-Audran, Martine; Bernier, Claire; Castelain, Florence; Collet, Evelyne; Crépy, Marie-Noëlle; Genillier, Nathalie; Girardin, Pascal; Pralong, Pauline; Tetart, Florence; Vital-Durand, Dominique; Soria, Angele; Barbaud, Annick

2017-09-01

Airborne allergic contact dermatitis caused by paints containing isothiazolinones has been recognized as a health hazard. To collect epidemiological, clinical and patch test data on airborne allergic contact dermatitis caused by isothiazolinone-containing paints in France and Belgium. A descriptive, retrospective study was initiated by the Dermatology and Allergy Group of the French Society of Dermatology, including methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI)- and/or MI-sensitized patients who developed airborne allergic contact dermatitis following exposure to isothiazolinone-containing paint. Forty-four cases were identified, with mostly non-occupational exposure (79.5%). Of the patients, 22.5% of also had mucosal symptoms. In several cases, the dermatitis required systemic corticosteroids (27.3%), hospitalization (9.1%), and/or sick leave (20.5%). A median delay of 5.5 weeks was necessary to enable patients to enter a freshly painted room without a flare-up of their dermatitis. Approximately one-fifth of the patients knew that they were allergic to MI and/or MCI/MI before the exposure to paints occurred. Our series confirms that airborne allergic contact dermatitis caused by paints containing isothiazolinones is not rare, and may be severe and long-lasting. Better regulation of isothiazolinone concentrations in paints, and their adequate labelling, is urgently needed. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Help-seeking patterns in women with postpartum severe mental illness: a report from southern India.

PubMed

Thippeswamy, Harish; Desai, Geetha; Chandra, Prabha

2018-03-21

Postpartum severe mental illness (SMI) often presents with risks to mother-infant dyad and requires early assessment and interventions. The access to psychiatric care in low and middle income countries is complex. Help-seeking patterns in women with postpartum SMI has not been studied adequately. Hence, the present study was undertaken to examine the help-seeking pattern and reasons for delay in seeking psychiatry services among postpartum women with SMI. Successive patients with a diagnosis of postpartum SMI were recruited over a period of 2 years. Clinical variables including the risk evaluation, perceived delay in seeking care along with the reasons were assessed through clinical interviews using a proforma. Severity of illness was assessed using BPRS and "encounter" form was used to assess the help-seeking pattern. One hundred twenty-three women with postpartum SMI participated in the study. Acute polymorphic psychotic disorder was the most common clinical presentation. Psychiatrists were the most commonly (52.8%) sought care providers followed by faith healers (26%) and general medical practitioners (GMP) (21.1%) at the first level of help seeking. A past history of psychiatric illness was significantly higher among those who first contacted a psychiatrist, and BPRS scores were significantly high among those who contacted a GMP. Forty-four percent of subjects perceived a delay in seeking care from psychiatry services and the most common reason was lack of resources. There is a need to enhance awareness about postpartum SMI in the community. Faith healers need to be sensitized about the associated risks and the need for early referrals. Addressing the barriers to psychiatric care would help in early detection and treatment of postpartum SMI.

Stability and delay sensitivity of neutral fractional-delay systems.

PubMed

Xu, Qi; Shi, Min; Wang, Zaihua

2016-08-01

This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

Delay-Line Three-Dimensional Position Sensitive Radiation Detection

NASA Astrophysics Data System (ADS)

Jeong, Manhee

High-resistivity silicon(Si) in large volumes and with good charge carrier transport properties has been produced and achieved success as a radiation detector material over the past few years due to its relatively low cost as well as the availability of well-established processing technologies. One application of that technology is in the fabrication of various position-sensing topologies from which the incident radiation's direction can be determined. We have succeeded in developing the modeling tools for investigating different position-sensing schemes and used those tools to examine both amplitude-based and time-based methods, an assessment that indicates that fine position-sensing can be achieved with simpler readout designs than are conventionally deployed. This realization can make ubiquitous and inexpensive deployment of special nuclear materials (SNM) detecting technology becomes more feasible because if one can deploy position-sensitive semiconductor detectors with only one or two contacts per side. For this purpose, we have described the delay-line radiation detector and its optimized fabrication. The semiconductor physics were simulated, the results from which guided the fabrication of the guard ring structure and the detector electrode, both of which included metal-field-plates. The measured improvement in the leakage current was confirmed with the fabricated devices, and the structures successfully suppressed soft-breakdown. We also demonstrated that fabricating an asymmetric strip-line structure successfully minimizing the pulse shaping and increases the distance through which one can propagate the information of the deposited charge distribution. With fabricated delay-line detectors we can acquire alpha spectra (Am-241) and gamma spectra (Ba-133, Co-57 and Cd-109). The delay-line detectors can therefore be used to extract the charge information from both ion and gamma-ray interactions. Furthermore, standard charge-sensitive circuits yield high SNR pulses. The detectors and existing electronics can therefore be used to yield imaging instruments for neutron and gamma-rays, in the case of silicon. For CZT, we would prefer to utilize current sensing to be able to clearly isolate the effects of the various charge-transport non-idealities, the full realization of which awaits the fabrication of the custom-designed TIA chip.

Rats bred for high alcohol drinking are more sensitive to delayed and probabilistic outcomes.

PubMed

Wilhelm, C J; Mitchell, S H

2008-10-01

Alcoholics and heavy drinkers score higher on measures of impulsivity than nonalcoholics and light drinkers. This may be because of factors that predate drug exposure (e.g. genetics). This study examined the role of genetics by comparing impulsivity measures in ethanol-naive rats selectively bred based on their high [high alcohol drinking (HAD)] or low [low alcohol drinking (LAD)] consumption of ethanol. Replicates 1 and 2 of the HAD and LAD rats, developed by the University of Indiana Alcohol Research Center, completed two different discounting tasks. Delay discounting examines sensitivity to rewards that are delayed in time and is commonly used to assess 'choice' impulsivity. Probability discounting examines sensitivity to the uncertain delivery of rewards and has been used to assess risk taking and risk assessment. High alcohol drinking rats discounted delayed and probabilistic rewards more steeply than LAD rats. Discount rates associated with probabilistic and delayed rewards were weakly correlated, while bias was strongly correlated with discount rate in both delay and probability discounting. The results suggest that selective breeding for high alcohol consumption selects for animals that are more sensitive to delayed and probabilistic outcomes. Sensitivity to delayed or probabilistic outcomes may be predictive of future drinking in genetically predisposed individuals.

Non-contact thickness measurement using UTG

NASA Technical Reports Server (NTRS)

Bui, Hoa T. (Inventor)

1996-01-01

A measurement structure for determining the thickness of a specimen without mechanical contact but instead employing ultrasonic waves including an ultrasonic transducer and an ultrasonic delay line connected to the transducer by a retainer or collar. The specimen, whose thickness is to be measured, is positioned below the delay line. On the upper surface of the specimen a medium such as a drop of water is disposed which functions to couple the ultrasonic waves from the delay line to the specimen. A receiver device, which may be an ultrasonic thickness gauge, receives reflected ultrasonic waves reflected from the upper and lower surface of the specimen and determines the thickness of the specimen based on the time spacing of the reflected waves.

Antimicrobial allergy from polyvinyl chloride gloves.

PubMed

Aalto-Korte, Kristiina; Alanko, Kristiina; Henriks-Eckerman, Maj-Len; Jolanki, Riitta

2006-10-01

Contact allergy to plastic gloves is rare. Benzisothiazolinone is a biocide that is mainly used in industrial settings. We first suspected delayed-type contact allergy to benzisothiazolinone from polyvinyl chloride (PVC) gloves in 2004. We looked through our medical records from 1991 to 2005 to find similar cases. We found a total of 8 patients who are allergic to benzisothiazolinone and who had had exacerbations of their hand dermatitis while using PVC gloves. Patch testing revealed that 3 of them had weak allergic or doubtful reactions to the glove materials. Six of them had used Evercare Soft, Medi-Point, or Derma Grip PVC gloves, which in chemical analysis were shown to contain 9 to 32 ppm of benzisothiazolinone. Seven of the patients worked in dentistry or health care and 1 in farming. All of them had had hand dermatitis for many years. To our knowledge, there have been no previous reports of contact allergy to antimicrobial agents in plastic gloves. Benzisothiazolinone is widely used as a biocide in the manufacture of disposable PVC gloves. Small amounts of benzisothiazolinone in the gloves may sensitize those who already have hand dermatitis. We recommend that all patients with hand dermatitis while using PVC gloves should be patch tested with benzisothiazolinone.

A Machine Learning Concept for DTN Routing

NASA Technical Reports Server (NTRS)

Dudukovich, Rachel; Hylton, Alan; Papachristou, Christos

2017-01-01

This paper discusses the concept and architecture of a machine learning based router for delay tolerant space networks. The techniques of reinforcement learning and Bayesian learning are used to supplement the routing decisions of the popular Contact Graph Routing algorithm. An introduction to the concepts of Contact Graph Routing, Q-routing and Naive Bayes classification are given. The development of an architecture for a cross-layer feedback framework for DTN (Delay-Tolerant Networking) protocols is discussed. Finally, initial simulation setup and results are given.

The role of lymphocyte proliferation tests in assessing occupational sensitization and disease

PubMed Central

Hines, Stella E.; Pacheco, Karin; Maier, Lisa A.

2018-01-01

Purpose of Review Lymphocyte proliferation testing (LPT) is used in diagnosing occupationally-acquired delayed-type hypersensitivity. It has been used in beryllium-health effects, and it role is expanding in metal allergy. It may find application in diagnosis of other sensitizers. Recent findings Use of the beryllium LPT (BeLPT) in medical surveillance identifies beryllium sensitization at low exposure with chronic beryllium disease (CBD) that leads to physiologic impairment and need for immunosuppressive medications. New studies indicate that both beryllium exposure and genetic variation are associated with increased risk of CBD. Borderline positive BeLPTs warrant inclusion into diagnostic algorithms. Furthermore, use of LPTs to diagnose metal allergy is being proposed in diagnosis of chromium allergy and hypersensitivity to surgical implants. New occupational sensitizers continue to be identified including metalworking fluids, the sterilizing agent ortho-phthalaldehyde and the solvent parachlorobenzotrifluoride. Use of LPT in occupational surveillance to these agents, and other known sensitizers may play expanding roles. Summary Lymphocyte proliferation testing serves a valuable role in diagnosing occupational sensitization, as demonstrated with beryllium-health effects, as cases continue to be found at low exposure levels. The use of LPTs in diagnosing contact allergy is expanding, and new applications may be identified in human and animal studies. PMID:22306552

Surface Acoustic Wave Monitor for Deposition and Analysis of Ultra-Thin Films

NASA Technical Reports Server (NTRS)

Hines, Jacqueline H. (Inventor)

2015-01-01

A surface acoustic wave (SAW) based thin film deposition monitor device and system for monitoring the deposition of ultra-thin films and nanomaterials and the analysis thereof is characterized by acoustic wave device embodiments that include differential delay line device designs, and which can optionally have integral reference devices fabricated on the same substrate as the sensing device, or on a separate device in thermal contact with the film monitoring/analysis device, in order to provide inherently temperature compensated measurements. These deposition monitor and analysis devices can include inherent temperature compensation, higher sensitivity to surface interactions than quartz crystal microbalance (QCM) devices, and the ability to operate at extreme temperatures.

Reducing Ageism: Education About Aging and Extended Contact With Older Adults.

PubMed

Lytle, Ashley; Levy, Sheri R

2017-11-19

Ageism is of increasing concern due to the growing older population worldwide and youth-centered focus of many societies. The current investigation tested the PEACE (Positive Education about Aging and Contact Experiences) model for the first time. Two online experimental studies examined 2 key factors for reducing ageism: education about aging (providing accurate information about aging) and extended contact (knowledge of positive intergenerational contact) as well as their potential combined effect (education plus extended contact). In Study 1, 354 undergraduates in all 3 experimental conditions (vs. control participants) reported less negative attitudes toward older adults (delayed post-test) and greater aging knowledge (immediate and delayed post-tests), when controlling for pre-study attitudes. In Study 2, 505 national community participants (ages 18-59) in all experimental conditions (vs. control participants) reported less negative attitudes toward older adults (immediate post-test) and greater aging knowledge (immediate and delayed post-tests). In summary, across 2 online studies, education about aging and knowledge of intergenerational extended contact improved attitudes toward older adults and aging knowledge. Thus, brief, online ageism-reduction strategies can be an effective way to combat ageism. These strategies hold promise to be tested in other settings, with other samples, and to be elaborated into more in-depth interventions that aim to reduce ageism in everyday culture. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Contact, Travel, and Transmission: The Impact of Winter Holidays on Influenza Dynamics in the United States

PubMed Central

Ewing, Anne; Lee, Elizabeth C.; Viboud, Cécile

2017-01-01

Abstract Background. The seasonality of influenza is thought to vary according to environmental factors and human behavior. During winter holidays, potential disease-causing contact and travel deviate from typical patterns. We aim to understand these changes on age-specific and spatial influenza transmission. Methods. We characterized the changes to transmission and epidemic trajectories among children and adults in a spatial context before, during, and after the winter holidays among aggregated physician medical claims in the United States from 2001 to 2009 and among synthetic data simulated from a deterministic, age-specific spatial metapopulation model. Results. Winter holidays reduced influenza transmission and delayed the trajectory of influenza season epidemics. The holiday period was marked by a shift in the relative risk of disease from children toward adults. Model results indicated that holidays delayed epidemic peaks and synchronized incidence across locations, and that contact reductions from school closures, rather than age-specific mixing and travel, produced these observed holiday influenza dynamics. Conclusions. Winter holidays delay seasonal influenza epidemic peaks and shift disease risk toward adults because of changes in contact patterns. These findings may inform targeted influenza information and vaccination campaigns during holiday periods. PMID:28031259

78 FR 18419 - Office of Hazardous Materials Safety; Delayed Applications

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration Office of Hazardous Materials Safety; Delayed Applications AGENCY: Pipeline and Hazardous Materials Safety.... FOR FURTHER INFORMATION CONTACT: Ryan Paquet, Director, Office of Hazardous Materials Special Permits...

Occupational skin hazards from synthetic plastics.

PubMed

Tosti, A; Guerra, L; Vincenzi, C; Peluso, A M

1993-01-01

Epoxy and acrylic resins have numerous industrial applications but are also widely used in the household environment. These compounds are presently one of the most important sources of occupational contact dermatitis. Contact sensitization to epoxy resins is usually caused by the resin itself but hardeners or other additives, such as reactive diluents, plasticizers, fillers and pigments, can occasionally be responsible. Since completely cured epoxy resins are not sensitizers, epoxy resin sensitization is always due to the presence, in the final polymer, of uncured allergenic low molecular weight oligomers. Acrylates are now considered the fourth most common cause of contact sensitization due to resins. Unpolymerized monomers of acrylic compounds are known to be responsible for the contact allergy. Accelerators, inhibitors and catalysts, which are usually added to the acrylates to promote the polymerization process, can also sensitize. Both allergic and irritant contact dermatitis may be caused by exposure to epoxy or acrylic resins and their additives. Contact urticaria, allergic or irritant airborne contact dermatitis caused by volatile compounds, onychia and paronychia can also occur. From January of 1984 to May of 1992 we detected 39 cases of occupational allergic contact dermatitis to epoxy resin system substances and 11 cases of occupational contact sensitization to acrylic compounds. In our experience, the electronics industry as well as paint and glue related activities were the most important sources of epoxy sensitization. Dental materials and anaerobic sealants were found to be the most frequent acrylate sensitizers.

Sensitivity analysis of dynamic biological systems with time-delays.

PubMed

Wu, Wu Hsiung; Wang, Feng Sheng; Chang, Maw Shang

2010-10-15

Mathematical modeling has been applied to the study and analysis of complex biological systems for a long time. Some processes in biological systems, such as the gene expression and feedback control in signal transduction networks, involve a time delay. These systems are represented as delay differential equation (DDE) models. Numerical sensitivity analysis of a DDE model by the direct method requires the solutions of model and sensitivity equations with time-delays. The major effort is the computation of Jacobian matrix when computing the solution of sensitivity equations. The computation of partial derivatives of complex equations either by the analytic method or by symbolic manipulation is time consuming, inconvenient, and prone to introduce human errors. To address this problem, an automatic approach to obtain the derivatives of complex functions efficiently and accurately is necessary. We have proposed an efficient algorithm with an adaptive step size control to compute the solution and dynamic sensitivities of biological systems described by ordinal differential equations (ODEs). The adaptive direct-decoupled algorithm is extended to solve the solution and dynamic sensitivities of time-delay systems describing by DDEs. To save the human effort and avoid the human errors in the computation of partial derivatives, an automatic differentiation technique is embedded in the extended algorithm to evaluate the Jacobian matrix. The extended algorithm is implemented and applied to two realistic models with time-delays: the cardiovascular control system and the TNF-α signal transduction network. The results show that the extended algorithm is a good tool for dynamic sensitivity analysis on DDE models with less user intervention. By comparing with direct-coupled methods in theory, the extended algorithm is efficient, accurate, and easy to use for end users without programming background to do dynamic sensitivity analysis on complex biological systems with time-delays.

[Radiation-induced modification of human somatic cell chromosome sensitivity to the testing mutagenic exposure of bleomycin in vitro in lung cancer patients in delayed terms following Chernobyl accident].

PubMed

Pilinskaia, M A; Dybskiĭ, S S; Dybskaia, E B; Shvaĭko, L I

2012-01-01

By using modified "G2-bleomycin sensitivity assay" above background level of cytogenetic effect considered as a marker of hidden chromosome instability (HCI) has been investigated in 3 groups--liquidators of Chernobyl accident (occupational group 1), patients with lung cancer who denied conscious contact--with ionizing radiation (group of comparison), liquidators with lung cancer (occupational group 2). Significant interindividual variations of cytogenetic effects induced with bleomycin and the lack of positive correlation between background and above background frequencies of chromosome aberrations have been shown in all observed groups. It had been established that occupational group 2 was the most burdened group by expression of the above background cytogenetic effect and, accordingly, number of persons with HCI. The data obtained permit to suggest the existence of the association between radiation-induced increase of individual sensitivity to testing mutagenic exposure and the realization of cancer in persons exposed to ionizing radiation. The results show acceptability of "G2-bleomycin sensitivity assay" under the cytogenetic examination of irradiated contingents for determining HCI as one of informative markers of predisposition to oncopathology.

Contact sensitivities in palmar plantar pustulosis (acropustulosis).

PubMed

Yiannias, J A; Winkelmann, R K; Connolly, S M

1998-09-01

Acropustulosis, or chronic palmar plantar pustulosis (PPP), is a phenomenon of recurrent sterile pustules, erythema, and scaling affecting the palms and soles. Its pathogenesis is unclear, and it is difficult to treat. The purpose of this study was to elucidate further the factors involved in causing PPP, thereby enhancing the ability to manage this disease. All cases of PPP seen at Mayo Clinic Scottsdale from 1987 to 1993 were reviewed. 21 patients with PPP were identified, 15 of whom had been patch tested. 9 of the 15 patients (60%) showed positive patch test results. Fragrance was the most common sensitivity, but nickel, formaldehyde, para-phenylenediamine, thiuram, neomycin, mercury, balsam of Peru, and cinnamic aldehyde sensitivities were demonstrated. Less important factors included atopy, fungal and bacterial infections, and irritation. Although the mechanism of this sterile pustulosis response does not depend solely on delayed hypersensitivity mechanisms, we believe that we have demonstrated such a large number of positive patch tests in this chronic pustular dermatosis that patch testing should be considered in the routine work-up of these patients.

DELAYED HYPERSENSITIVITY

PubMed Central

Uhr, Jonathan W.; Salvin, S. B.; Pappenheimer, A. M.

1957-01-01

A general method for induction of the delayed hypersensitive state directed against single protein antigens is described. The method consists of intradermal injection of minute amounts of washed immune precipitates containing the antigen in question. Provided the specific precipitates are formed in the region of antibody excess, maximal sensitivity develops at least 2 to 3 weeks before detectable circulating antibody is formed in guinea pigs against the sensitizing antigen. Neither adjuvant nor killed acid-fast bacteria are required for induction of the delayed hypersensitive state although the degree of sensitization is considerably increased when the sensitizing material is incorporated in Freund's complete adjuvant. Characteristics of the "delayed" as opposed to the "immediate" hypersensitive states in the guinea pig are described and implications of the findings are discussed. PMID:13385403

How do patients access the private sector in Chennai, India? An evaluation of delays in tuberculosis diagnosis.

PubMed

Bronner Murrison, L; Ananthakrishnan, R; Swaminathan, A; Auguesteen, S; Krishnan, N; Pai, M; Dowdy, D W

2016-04-01

The diagnosis and treatment of tuberculosis (TB) in India are characterized by heavy private-sector involvement. Delays in treatment remain poorly characterized among patients seeking care in the Indian private sector. To assess delays in TB diagnosis and treatment initiation among patients diagnosed in the private sector, and pathways to care in an urban setting. Cross-sectional survey of 289 consecutive patients diagnosed with TB in the private sector and referred for anti-tuberculosis treatment through a public-private mix program in Chennai from January 2014 to February 2015. Among 212 patients with pulmonary TB, 90% first contacted a formal private provider, and 78% were diagnosed by the first or second provider seen after a median of three visits per provider. Median total delay was 51 days (mean 68). Consulting an informal (rather than formally trained) provider first was associated with significant increases in total delay (absolute increase 22.8 days, 95%CI 6.2-39.5) and in the risk of prolonged delay >90 days (aRR 2.4, 95%CI 1.3-4.4). Even among patients seeking care in the formal (vs. informal) private sector in Chennai, diagnostic delays are substantial. Novel strategies are required to engage private providers, who often serve as the first point of contact.

Circadian phase, dynamics of subjective sleepiness and sensitivity to blue light in young adults complaining of a delayed sleep schedule.

PubMed

Moderie, Christophe; Van der Maren, Solenne; Dumont, Marie

2017-06-01

To assess factors that might contribute to a delayed sleep schedule in young adults with sub-clinical features of delayed sleep phase disorder. Two groups of 14 young adults (eight women) were compared: one group complaining of a delayed sleep schedule and a control group with an earlier bedtime and no complaint. For one week, each subject maintained a target bedtime reflecting their habitual sleep schedule. Subjects were then admitted to the laboratory for the assessment of circadian phase (dim light melatonin onset), subjective sleepiness, and non-visual light sensitivity. All measures were timed relative to each participant's target bedtime. Non-visual light sensitivity was evaluated using subjective sleepiness and salivary melatonin during 1.5-h exposure to blue light, starting one hour after target bedtime. Compared to control subjects, delayed subjects had a later circadian phase and a slower increase of subjective sleepiness in the late evening. There was no group difference in non-visual sensitivity to blue light, but we found a positive correlation between melatonin suppression and circadian phase within the delayed group. Our results suggest that a late circadian phase, a slow build-up of sleep need, and an increased circadian sensitivity to blue light contribute to the complaint of a delayed sleep schedule. These findings provide targets for strategies aiming to decreasing the severity of a sleep delay and the negative consequences on daytime functioning and health. Copyright © 2017 Elsevier B.V. All rights reserved.

77 FR 58217 - Notice of Delays in Processing of Special Permits Applications

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-19

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration Notice of Delays in Processing of Special Permits Applications AGENCY: Pipeline and Hazardous Materials Safety.... FOR FURTHER INFORMATION CONTACT: Ryan Paquet, Director, Office of Hazardous Materials Special Permits...

77 FR 64846 - Notice of Delays in Processing of Special Permits Applications

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-23

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration Notice of Delays in Processing of Special Permits Applications AGENCY: Pipeline and Hazardous Materials Safety.... FOR FURTHER INFORMATION CONTACT: Ryan Paquet, Director, Office of Hazardous Materials Special Permits...

[Epidemiology of contact dermatitis: prevalence of sensitization to different allergens and associated factors].

PubMed

Bordel-Gómez, Ma T; Miranda-Romero, A; Castrodeza-Sanz, J

2010-01-01

In clinical practice, contact dermatitis is a relatively common skin complaint, whose prevalence has increased in recent years. Study by patch testing is essential for diagnosis of contact sensitization. To study the prevalence of sensitization to different allergens in a standard battery and observe the influence of different epidemiological and clinical variables on contact sensitization. A large number of allergens were included in our battery in order to detect new sensitizations whose prevalence might justify further study. This was a retrospective, observational, epidemiological study of 1092 patients, conducted in our skin allergy unit between January 1, 2000, and December 31, 2005. All patients were studied with a battery of 51 allergens. We assessed the following variables: sex, age, type of referral, occupation, site and course of skin lesions, personal and family history of atopy, positive patch tests, clinical significance, diagnosis, source of sensitization, and occupational relationship. At least 1 positive result was found in 55% of the patients, and 55.7% presented atopic dermatitis in one of its clinical variants: allergic contact dermatitis (28.2%), irritant contact dermatitis (20.1%), photoallergic contact dermatitis (2.2%), and phototoxic contact dermatitis (1.2%). The most prevalent allergens were nickel sulfate (29.3%), palladium chloride (11.7%), cobalt chloride (10.8%), potassium dichromate (7.5%), fragrance blends (6.3%), and p-phenylenediamine (6.1%). A positive occupational relationship was found in 41.1%, and 21.3% of the patients studied were diagnosed with occupational contact dermatitis. Metal workers, construction workers, and professional hairdressers were the most strongly represented groups. The most common source of sensitization was contact with metallic objects, followed by drugs, cosmetics, and rubber items. Female sex was the only independent variable that had a significant influence on the risk of contact sensitization in general. Women became sensitized at a younger age than men, and the frequency of positive results in the patch tests increased with age, reaching a maximum at between 60 and 69 years of age, when the greatest rate of sensitization occurred. Comparison of our results with other Spanish data showed a progressive and constant increase in sensitization to nickel sulfate, fragrance blends, balsam of Peru, and rosin, and a decrease in sensitization to potassium dichromate. The inclusion of new allergens such as palladium chloride, diallyl disulfide, and p-toluene sulfonamide formaldehyde improved the sensitivity of the standard battery in the detection of contact sensitization. We therefore recommend further studies of these allergens.

Impact of treatment delay on mortality in ST-segment elevation myocardial infarction (STEMI) patients presenting with and without haemodynamic instability: results from the German prospective, multicentre FITT-STEMI trial.

PubMed

Scholz, Karl Heinrich; Maier, Sebastian K G; Maier, Lars S; Lengenfelder, Björn; Jacobshagen, Claudius; Jung, Jens; Fleischmann, Claus; Werner, Gerald S; Olbrich, Hans G; Ott, Rainer; Mudra, Harald; Seidl, Karlheinz; Schulze, P Christian; Weiss, Christian; Haimerl, Josef; Friede, Tim; Meyer, Thomas

2018-04-01

The aim of this study was to investigate the effect of contact-to-balloon time on mortality in ST-segment elevation myocardial infarction (STEMI) patients with and without haemodynamic instability. Using data from the prospective, multicentre Feedback Intervention and Treatment Times in ST-Elevation Myocardial Infarction (FITT-STEMI) trial, we assessed the prognostic relevance of first medical contact-to-balloon time in n = 12 675 STEMI patients who used emergency medical service transportation and were treated with primary percutaneous coronary intervention (PCI). Patients were stratified by cardiogenic shock (CS) and out-of-hospital cardiac arrest (OHCA). For patients treated within 60 to 180 min from the first medical contact, we found a nearly linear relationship between contact-to-balloon times and mortality in all four STEMI groups. In CS patients with no OHCA, every 10-min treatment delay resulted in 3.31 additional deaths in 100 PCI-treated patients. This treatment delay-related increase in mortality was significantly higher as compared to the two groups of OHCA patients with shock (2.09) and without shock (1.34), as well as to haemodynamically stable patients (0.34, P < 0.0001). In patients with CS, the time elapsing from the first medical contact to primary PCI is a strong predictor of an adverse outcome. This patient group benefitted most from immediate PCI treatment, hence special efforts to shorten contact-to-balloon time should be applied in particular to these high-risk STEMI patients. NCT00794001.

Delay Discounting of Qualitatively Different Reinforcers in Rats

ERIC Educational Resources Information Center

Calvert, Amanda L.; Green, Leonard; Myerson, Joel

2010-01-01

Humans discount larger delayed rewards less steeply than smaller rewards, whereas no such magnitude effect has been observed in rats (and pigeons). It remains possible that rats' discounting is sensitive to differences in the quality of the delayed reinforcer even though it is not sensitive to amount. To evaluate this possibility, Experiment 1…

Contact, Travel, and Transmission: The Impact of Winter Holidays on Influenza Dynamics in the United States.

PubMed

Ewing, Anne; Lee, Elizabeth C; Viboud, Cécile; Bansal, Shweta

2017-03-01

The seasonality of influenza is thought to vary according to environmental factors and human behavior. During winter holidays, potential disease-causing contact and travel deviate from typical patterns. We aim to understand these changes on age-specific and spatial influenza transmission. We characterized the changes to transmission and epidemic trajectories among children and adults in a spatial context before, during, and after the winter holidays among aggregated physician medical claims in the United States from 2001 to 2009 and among synthetic data simulated from a deterministic, age-specific spatial metapopulation model. Winter holidays reduced influenza transmission and delayed the trajectory of influenza season epidemics. The holiday period was marked by a shift in the relative risk of disease from children toward adults. Model results indicated that holidays delayed epidemic peaks and synchronized incidence across locations, and that contact reductions from school closures, rather than age-specific mixing and travel, produced these observed holiday influenza dynamics. Winter holidays delay seasonal influenza epidemic peaks and shift disease risk toward adults because of changes in contact patterns. These findings may inform targeted influenza information and vaccination campaigns during holiday periods. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Immune suppression with supraoptimal doses of antigen in contact sensitivity. I. Demonstration of suppressor cells and their sensitivity to cyclophosphamide.

PubMed

Sy, M S; Miller, S D; Claman, H N

1977-07-01

Immunologic suppression was induced in a mouse model of contact sensitization to DNFB by using supraoptimal doses of antigen. In these studies, in vivo measurement of ear swelling as an indication of immunologic responsiveness correlated well with measurement of in vitro antigen-induced cell proliferation. This unresponsiveness was specific, since supraoptimal doses of DNFB did not interfere with the development of contact sensitivity to another contactant, oxazolone. The decrease in responsiveness is a form of active suppression, as lymphoid cells from supraoptimally sensitized donors transferred suppression to normal recipients. Furthermore, pretreatment with cyclophosphamide (Cy) reversed the suppression seen in supraoptimally sensitized animals but had no effect on the optimal sensitization regimen. These results indicate that supraoptimal doses of contactants can activate suppressor cells and that precursors of these cells are sensitive to Cy. Such suppressors regenerate within 7 to 14 days after Cy treatment. The ability of Cy pretreatment to affect supraoptimal sensitization without affecting optimal sensitization confirms other reports indicating that the observed results of Cy treatment depend critically upon the dose of antigen used.

Radiation dependence of inverter propagation delay from timing sampler measurements

NASA Technical Reports Server (NTRS)

Buehler, M. G.; Blaes, B. R.; Lin, Y.-S.

1989-01-01

A timing sampler consisting of 14 four-stage inverter-pair chains with different load capacitances was fabricated in 1.6-micron n-well CMOS and irradiated with cobalt-60 at 10 rad(Si)/s. For this CMOS process the measured results indicate that the rising delay increases by about 2.2 ns/Mrad(Si) and the falling delay increase is very small, i.e., less than 300 ps/Mrad(Si). The amount of radiation-induced delay depends on the size of the load capacitance. The maximum value observed for this effect was 5.65 ns/pF-Mrad(Si). Using a sensitivity analysis, the sensitivity of the rising delay to radiation can be explained by a simple timing model and the radiation sensitivity of dc MOSFET parameters. This same approach could not explain the insensitivity of the falling delay to radiation. This may be due to a failure of the timing model and/or trapping effects.

Effects of microgravity on vestibular development and function in rats: genetics and environment

NASA Technical Reports Server (NTRS)

Ronca, A. E.; Fritzsch, B.; Alberts, J. R.; Bruce, L. L.

2000-01-01

Our anatomical and behavioral studies of embryonic rats that developed in microgravity suggest that the vestibular sensory system, like the visual system, has genetically mediated processes of development that establish crude connections between the periphery and the brain. Environmental stimuli also regulate connection formation including terminal branch formation and fine-tuning of synaptic contacts. Axons of vestibular sensory neurons from gravistatic as well as linear acceleration receptors reach their targets in both microgravity and normal gravity, suggesting that this is a genetically regulated component of development. However, microgravity exposure delays the development of terminal branches and synapses in gravistatic but not linear acceleration-sensitive neurons and also produces behavioral changes. These latter changes reflect environmentally controlled processes of development.

Acute and chronic systemic chromium toxicity.

PubMed

Gad, S C

1989-10-01

Although chromium and compounds containing it have been recognized as having potential severe adverse effects on health for more than 160 years, understanding of the systemic toxicology and true hazard of these compounds is still not complete. A review of the current state of knowledge is attempted in this paper, with appropriate attention given to the complications of multiple valence states and solubility. Selected chromium compounds, particularly hexavalent ones, are carcinogens, corrosives, delayed contact sensitizers, and have the kidney as their primary target organ. But chromium is also an essential element for humans. The body clearly possesses some effective detoxification mechanisms for some degree of exposure to hexavalent chrome compounds. The significant features of acute and chronic chromium toxicity are presented in view of these considerations.

Binaural interaction in low-frequency neurons in inferior colliculus of the cat. I. Effects of long interaural delays, intensity, and repetition rate on interaural delay function.

PubMed

Kuwada, S; Yin, T C

1983-10-01

Detailed, quantitative studies were made of the interaural phase sensitivity of 197 neurons with low best frequency in the inferior colliculus (IC) of the barbiturate-anesthetized cat. We analyzed the responses of single cells to interaural delays in which tone bursts were delivered to the two ears via sealed earphones and the onset of the tone to one ear with respect to the other was varied. For most (80%) cells the discharge rate is a cyclic function of interaural delay at a period corresponding to that of the stimulating frequency. The cyclic nature of the interaural delay curve indicates that these cells are sensitive to the interaural phase difference. These cells are distributed throughout the low-frequency zone of the IC, but they are less numerous in the medial and caudal zones. Cells with a wide variety of response patterns will exhibit interaural phase sensitivities at stimulating frequencies up to 3,100 Hz, although above 2,500 Hz the number of such cells decrease markedly. Using dichotic stimuli we could study the cell's sensitivity to the onset delay and interaural phase independently. The large majority of IC cells respond only to changes in interaural phase, with no sensitivity to the onset delay. However, a small number (7%) of cells exhibit a sensitivity to the onset delay as well as to the interaural phase disparity, and most of these cells show an onset response. The effects of changing the stimulus intensity equally to both ears or of changing the interaural intensity difference on the mean interaural phase were studied. While some neurons are not affected by level changes, others exhibit systematic phase shifts for both average and interaural intensity variations, and there is a continuous distribution of sensitivities between these extremes. A few cells also showed systematic changes in the shape of the interaural delay curves as a function of interaural intensity difference, especially at very long delays. These shifts can be interpreted as a form of time-intensity trading. A few cells demonstrated orderly changes in the interaural delay curve as the repetition rate of the stimulus was varied. Some of these changes are consonant with an inhibitory effect that occurs at stimulus offset. The responses of the neurons show a strong bias for stimuli that would originate from he contralateral sound field; 77% of the responses display mean interaural phase angles that are less than 0.5 of a cycle, which are delays to the ipsilateral tone.(ABSTRACT TRUNCATED AT 400 WORDS)

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay

PubMed Central

Strickland, Justin C.; Feinstein, Max A.; Lacy, Ryan T.; Smith, Mark A.

2016-01-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-second delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. PMID:26964905

Infant and Maternal Sensitivity to Interpersonal Timing

ERIC Educational Resources Information Center

Henning, Anne; Striano, Tricia

2011-01-01

A perturbation paradigm was employed to assess 3- and 6-month-old infants' and their mothers' sensitivity to a 3-s temporal delay implemented in an ongoing televised interaction. At both ages, the temporal delay affected infant but not maternal behavior and only when implementing the temporal delay in maternal (Experiment 1, N = 64) but not infant…

[Anaphylactic reactions to low-molecular weight chemicals].

PubMed

Nowak, Daria; Panaszek, Bernard

2015-02-06

Low-molecular weight chemicals (haptens) include a large group of chemical compounds occurring in work environment, items of everyday use (cleaning products, clothing, footwear, gloves, furniture), jewelry (earrings, bracelets), drugs, especially in cosmetics. They cause type IV hypersensitive reactions. During the induction phase of delayed-type hypersensitivity, haptens form complexes with skin proteins. After internalization through antigen presenting cells, they are bound to MHC class II molecules. Next, they are exposed against specific T-lymphocytes, what triggers activation of Th1 cells mainly. After repeating exposition to that hapten, during effector phase, Th1 induce production of cytokines affecting non-specific inflammatory cells. Usually, it causes contact dermatitis. However, occasionally incidence of immediate generalized reactions after contact with some kinds of haptens is noticed. A question arises, how the hapten does induce symptoms which are typical for anaphylaxis, and what contributes to amplification of this mechanism. It seems that this phenomenon arises from pathomechanism occurring in contact urticaria syndrome in which an anaphylactic reaction may be caused either by contact of sensitized skin with protein antigens, high-molecular weight allergens, or haptens. One of the hypotheses indicates the leading role of basophiles in this process. Their contact with haptens, may cause to release mediators of immediate allergic reaction (histamine, eicosanoids) and to produce cytokines corresponding to Th2 cells profile. Furthermore, Th17 lymphocytes secreting pro-inflammatory interleukin-17 might be engaged into amplifying hypersensitivity into immediate reactions and regulatory T-cells may play role in the process, due to insufficient control of the activity of effector cells.

Home Healthcare Workers: How to Prevent Latex Allergies

MedlinePlus

... delayed hypersensitivity) This skin reaction looks like the rash from contact with poison ivy and usually shows up 24– ... after using gloves. • Recognize symptoms of latex allergy (rash; hives; flushing; ... Avoid direct contact with latex gloves and other latex-containing products ...

Sociocultural determinants of the help-seeking behavior of patients with mental illness.

PubMed

Lin, K M; Inui, T S; Kleinman, A M; Womack, W M

1982-02-01

This descriptive study employed semistructured interviewing and questionnaire administration to delineate the sociocultural determinants of the help-seeking process in 48 psychiatric patients. The help-seeking process is considered in two stages. The first stage starts from the recognition of initial symptoms and ends in the first contact with a mental health professional. The second stage is defined as that time between the first contact and actual participation in a planned treatment program. In both stages, patients typically go through phases of lay consultation, nonpsychiatric professional consultation, and referral. The multiple steps which are usually involved in help seeking often result in significant delay of both mental health contact and treatment. The help-seeking process was found to correlate strongly with ethnicity. Both Asians and Blacks showed more extended family involvement, and the involvement of key family members tended to be persistent and intensive in Asians. Ethnicity was also associated with the length of delay, with Asians showing the longest delay and Caucasians the least. These ethnic differences were also reflected in help-seeking pathway assignment using Lin's criteria. Although modernity and parochialism, as measured by the level of modernization and the cohesiveness of the social network system of the subjects, were also found to be correlated with delay, they appeared to exert an influence independent from that of ethnicity.

A high resolution on-chip delay sensor with low supply-voltage sensitivity for high-performance electronic systems.

PubMed

Sheng, Duo; Lai, Hsiu-Fan; Chan, Sheng-Min; Hong, Min-Rong

2015-02-13

An all-digital on-chip delay sensor (OCDS) circuit with high delay-measurement resolution and low supply-voltage sensitivity for efficient detection and diagnosis in high-performance electronic system applications is presented. Based on the proposed delay measurement scheme, the quantization resolution of the proposed OCDS can be reduced to several picoseconds. Additionally, the proposed cascade-stage delay measurement circuit can enhance immunity to supply-voltage variations of the delay measurement resolution without extra self-biasing or calibration circuits. Simulation results show that the delay measurement resolution can be improved to 1.2 ps; the average delay resolution variation is 0.55% with supply-voltage variations of ±10%. Moreover, the proposed delay sensor can be implemented in an all-digital manner, making it very suitable for high-performance electronic system applications as well as system-level integration.

Sensitivity of medial and lateral knee contact force predictions to frontal plane alignment and contact locations.

PubMed

Saliba, Christopher M; Brandon, Scott C E; Deluzio, Kevin J

2017-05-24

Musculoskeletal models are increasingly used to estimate medial and lateral knee contact forces, which are difficult to measure in vivo. The sensitivity of contact force predictions to modeling parameters is important to the interpretation and implication of results generated by the model. The purpose of this study was to quantify the sensitivity of knee contact force predictions to simultaneous errors in frontal plane knee alignment and contact locations under different dynamic conditions. We scaled a generic musculoskeletal model for N=23 subjects' stature and radiographic knee alignment, then perturbed frontal plane alignment and mediolateral contact locations within experimentally-possible ranges of 10° to -10° and 10 to -10mm, respectively. The sensitivity of first peak, second peak, and mean medial and lateral knee contact forces to knee adduction angle and contact locations was modeled using linear regression. Medial loads increased, and lateral loads decreased, by between 3% and 6% bodyweight for each degree of varus perturbation. Shifting the medial contact point medially increased medial loads and decreased lateral loads by between 1% and 4% bodyweight per millimeter. This study demonstrates that realistic measurement errors of 5mm (contact distance) or 5° (frontal plane alignment) could result in a combined 50% BW error in subject specific contact force estimates. We also show that model sensitivity varies between subjects as a result of differences in gait dynamics. These results demonstrate that predicted knee joint contact forces should be considered as a range of possible values determined by model uncertainty. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluation of touch-sensitive screen tablet terminal button size and spacing accounting for effect of fingertip contact angle.

PubMed

Nishimura, T; Doi, K; Fujimoto, H

2015-08-01

Touch-sensitive screen terminals enabling intuitive operation are used as input interfaces in a wide range of fields. Tablet terminals are one of the most common devices with a touch-sensitive screen. They have a feature of good portability, enabling use under various conditions. On the other hand, they require a GUI designed to prevent decrease of usability under various conditions. For example, the angle of fingertip contact with the display changes according to finger posture during operation and how the case is held. When a human fingertip makes contact with an object, the contact area between the fingertip and contact object increases or decreases as the contact angle changes. A touch-sensitive screen detects positions using the change in capacitance of the area touched by the fingertip; hence, differences in contact area between the touch-sensitive screen and fingertip resulting from different forefinger angles during operation could possibly affect operability. However, this effect has never been studied. We therefore conducted an experiment to investigate the relationship between size/spacing and operability, while taking the effect of fingertip contact angle into account. As a result, we have been able to specify the button size and spacing conditions that enable accurate and fast operation regardless of the forefinger contact angle.

7 CFR 1291.10 - Reporting and oversight requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

..., identify and share the lessons learned to help expedite problem-solving. (6) Contact Person. List the... period to meet measurable outcomes for each project. (2) Problems and Delays. Note unexpected delays or... include the following: (1) Project Summary. An outline of the issue, problem, interest, or need for each...

The effects of physical activity on impulsive choice: Influence of sensitivity to reinforcement amount and delay.

PubMed

Strickland, Justin C; Feinstein, Max A; Lacy, Ryan T; Smith, Mark A

2016-05-01

Impulsive choice is a diagnostic feature and/or complicating factor for several psychological disorders and may be examined in the laboratory using delay-discounting procedures. Recent investigators have proposed using quantitative measures of analysis to examine the behavioral processes contributing to impulsive choice. The purpose of this study was to examine the effects of physical activity (i.e., wheel running) on impulsive choice in a single-response, discrete-trial procedure using two quantitative methods of analysis. To this end, rats were assigned to physical activity or sedentary groups and trained to respond in a delay-discounting procedure. In this procedure, one lever always produced one food pellet immediately, whereas a second lever produced three food pellets after a 0, 10, 20, 40, or 80-s delay. Estimates of sensitivity to reinforcement amount and sensitivity to reinforcement delay were determined using (1) a simple linear analysis and (2) an analysis of logarithmically transformed response ratios. Both analyses revealed that physical activity decreased sensitivity to reinforcement amount and sensitivity to reinforcement delay. These findings indicate that (1) physical activity has significant but functionally opposing effects on the behavioral processes that contribute to impulsive choice and (2) both quantitative methods of analysis are appropriate for use in single-response, discrete-trial procedures. Copyright © 2016 Elsevier B.V. All rights reserved.

Measurement of collective dynamical mass of Dirac fermions in graphene.

PubMed

Yoon, Hosang; Forsythe, Carlos; Wang, Lei; Tombros, Nikolaos; Watanabe, Kenji; Taniguchi, Takashi; Hone, James; Kim, Philip; Ham, Donhee

2014-08-01

Individual electrons in graphene behave as massless quasiparticles. Unexpectedly, it is inferred from plasmonic investigations that electrons in graphene must exhibit a non-zero mass when collectively excited. The inertial acceleration of the electron collective mass is essential to explain the behaviour of plasmons in this material, and may be directly measured by accelerating it with a time-varying voltage and quantifying the phase delay of the resulting current. This voltage-current phase relation would manifest as a kinetic inductance, representing the reluctance of the collective mass to accelerate. However, at optical (infrared) frequencies, phase measurements of current are generally difficult, and, at microwave frequencies, the inertial phase delay has been buried under electron scattering. Therefore, to date, the collective mass in graphene has defied unequivocal measurement. Here, we directly and precisely measure the kinetic inductance, and therefore the collective mass, by combining device engineering that reduces electron scattering and sensitive microwave phase measurements. Specifically, the encapsulation of graphene between hexagonal boron nitride layers, one-dimensional edge contacts and a proximate top gate configured as microwave ground together enable the inertial phase delay to be resolved from the electron scattering. Beside its fundamental importance, the kinetic inductance is found to be orders of magnitude larger than the magnetic inductance, which may be utilized to miniaturize radiofrequency integrated circuits. Moreover, its bias dependency heralds a solid-state voltage-controlled inductor to complement the prevalent voltage-controlled capacitor.

Lysophosphatidylcholine hydrolases of human erythrocytes, lymphocytes, and brain: Sensitive targets of conserved specificity for organophosphorus delayed neurotoxicants

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

Vose, Sarah C.; Center for Children's Environmental Health Research, School of Public Health, University of California, Berkeley, CA 94720; Holland, Nina T.

2007-10-01

Brain neuropathy target esterase (NTE), associated with organophosphorus (OP)-induced delayed neuropathy, has the same OP inhibitor sensitivity and specificity profiles assayed in the classical way (paraoxon-resistant, mipafox-sensitive hydrolysis of phenyl valerate) or with lysophosphatidylcholine (LysoPC) as the substrate. Extending our earlier observation with mice, we now examine human erythrocyte, lymphocyte, and brain LysoPC hydrolases as possible sensitive targets for OP delayed neurotoxicants and insecticides. Inhibitor profiling of human erythrocytes and lymphocytes gave the surprising result of essentially the same pattern as with brain. Human erythrocyte LysoPC hydrolases are highly sensitive to OP delayed neurotoxicants, with in vitro IC{sub 50} valuesmore » of 0.13-85 nM for longer alkyl analogs, and poorly sensitive to the current OP insecticides. In agricultural workers, erythrocyte LysoPC hydrolyzing activities are similar for newborn children and their mothers and do not vary with paraoxonase status but have high intersample variation that limits their use as a biomarker. Mouse erythrocyte LysoPC hydrolase activity is also of low sensitivity in vitro and in vivo to the OP insecticides whereas the delayed neurotoxicant ethyl n-octylphosphonyl fluoride inhibits activity in vivo at 1-3 mg/kg. Overall, inhibition of blood LysoPC hydrolases is as good as inhibition of brain NTE as a predictor of OP inducers of delayed neuropathy. NTE and lysophospholipases (LysoPLAs) both hydrolyze LysoPC, yet they are in distinct enzyme families with no sequence homology and very different catalytic sites. The relative contributions of NTE and LysoPLAs to LysoPC hydrolysis and clearance from erythrocytes, lymphocytes, and brain remain to be defined.« less

Sensitivity and Switching Delay in Trigger Circuits; SENSIBILITA E RITARDO ENI CIRCUITI A SCATTO

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

De Lotto, I.; Stanchi, L.

The problem of regeneration in trigger circuits is studied, particularly in relation to switching delay and switching time. The factors that affect the speed, such as the threshold as a function of the input signal duration, are examined. The sensitivity of the circuit is also discussed. The characteristics of the dipole equivalent to a trigger circuit are determined, and the switching delay and switching rise time are examined using considerable simplifications (circuits with constant parameters) and graphical methods. For the particular case of a transistor circuit, the equation of the equivalent circuit is derived taking into account the nonlinearity ofmore » the parameters. This equation is processed by means of an analog computer. Using experimental data, the circuits are classified according to their sensitivity and the switching delay. A merit figure is obtained for synthetically evaluating different circuits and optimizing circuit sensitivity and speed. (auth)« less

10-Minute Delayed Recall from the Modified Mini-Mental State Test Predicts Alzheimer’s Disease Pathology

PubMed Central

Lyness, Scott A.; Lee, Ae Young; Zarow, Chris; Teng, Evelyn L.; Chui, Helena C.

2014-01-01

We compared the sensitivity and specificity of two delayed recall scores from the Modified Mini-Mental State (3MS) test with consensus clinical diagnosis to differentiate cognitive impairment due to Alzheimer’s disease (AD) versus non-AD pathologies. At a memory disorders clinic, 117 cognitively impaired patients were administered a baseline 3MS test and received a contemporaneous consensus clinical diagnosis. Their brains were examined after death about 5 years later. Using logistic regression with forward selection to predict pathologically defined AD versus non-AD, 10-min delayed recall entered first (p = 0.001), followed by clinical diagnosis (p = 0.02); 1-min delayed recall did not enter. 10-min delayed recall scores ≤4 (score range = 0–9) were 87% sensitive and 47% specific in predicting AD pathology; consensus clinical diagnosis was 82% sensitive and 45% specific. For the 57 patients whose initial Mini-Mental State Examination scores were ≥19 (the median), 3MS 10-min delayed recall scores ≤4 showed some loss of sensitivity (80%) but a substantial gain in specificity (77%). In conclusion, 10-min delayed recall score on the brief 3MS test distinguished between AD versus non-AD pathology about 5 years before death at least as well as consensus clinical diagnosis that requires much more comprehensive information and complex deliberation. PMID:24240637

An Improved Forwarding of Diverse Events with Mobile Sinks in Underwater Wireless Sensor Networks.

PubMed

Raza, Waseem; Arshad, Farzana; Ahmed, Imran; Abdul, Wadood; Ghouzali, Sanaa; Niaz, Iftikhar Azim; Javaid, Nadeem

2016-11-04

In this paper, a novel routing strategy to cater the energy consumption and delay sensitivity issues in deep underwater wireless sensor networks is proposed. This strategy is named as ESDR: Event Segregation based Delay sensitive Routing. In this strategy sensed events are segregated on the basis of their criticality and, are forwarded to their respective destinations based on forwarding functions. These functions depend on different routing metrics like: Signal Quality Index, Localization free Signal to Noise Ratio, Energy Cost Function and Depth Dependent Function. The problem of incomparable values of previously defined forwarding functions causes uneven delays in forwarding process. Hence forwarding functions are redefined to ensure their comparable values in different depth regions. Packet forwarding strategy is based on the event segregation approach which forwards one third of the generated events (delay sensitive) to surface sinks and two third events (normal events) are forwarded to mobile sinks. Motion of mobile sinks is influenced by the relative distribution of normal nodes. We have also incorporated two different mobility patterns named as; adaptive mobility and uniform mobility for mobile sinks. The later one is implemented for collecting the packets generated by the normal nodes. These improvements ensure optimum holding time, uniform delay and in-time reporting of delay sensitive events. This scheme is compared with the existing ones and outperforms the existing schemes in terms of network lifetime, delay and throughput.

10-minute delayed recall from the modified mini-mental state test predicts Alzheimer's disease pathology.

PubMed

Lyness, Scott A; Lee, Ae Young; Zarow, Chris; Teng, Evelyn L; Chui, Helena C

2014-01-01

We compared the sensitivity and specificity of two delayed recall scores from the Modified Mini-Mental State (3MS) test with consensus clinical diagnosis to differentiate cognitive impairment due to Alzheimer's disease (AD) versus non-AD pathologies. At a memory disorders clinic, 117 cognitively impaired patients were administered a baseline 3MS test and received a contemporaneous consensus clinical diagnosis. Their brains were examined after death about 5 years later. Using logistic regression with forward selection to predict pathologically defined AD versus non-AD, 10-min delayed recall entered first (p = 0.001), followed by clinical diagnosis (p = 0.02); 1-min delayed recall did not enter. 10-min delayed recall scores ≤4 (score range = 0-9) were 87% sensitive and 47% specific in predicting AD pathology; consensus clinical diagnosis was 82% sensitive and 45% specific. For the 57 patients whose initial Mini-Mental State Examination scores were ≥19 (the median), 3MS 10-min delayed recall scores ≤4 showed some loss of sensitivity (80%) but a substantial gain in specificity (77%). In conclusion, 10-min delayed recall score on the brief 3MS test distinguished between AD versus non-AD pathology about 5 years before death at least as well as consensus clinical diagnosis that requires much more comprehensive information and complex deliberation.

Effects of N-methyl-D-aspartate receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure

PubMed Central

Yates, Justin R; Gunkel, Benjamin T; Rogers, Katherine K; Hughes, Mallory N; Prior, Nicholas A

2016-01-01

Rationale The N-methyl-D-aspartate (NMDA) receptor has been recently identified as an important mediator of impulsive choice, as assessed in delay discounting. Although discounting is independently influenced by sensitivity to reinforcer magnitude and delayed reinforcement, few studies have examined how NMDA receptor ligands differentially affect these parameters. Objectives The current study examined the effects of various NMDA receptor ligands on sensitivity to reinforcer magnitude and delayed reinforcement in a delay-discounting procedure. Methods Following behavioral training, rats received treatments of the following NMDA receptor ligands: the uncompetitive antagonists ketamine (0, 1.0, 5.0, or 10.0 mg/kg; i.p.), MK-801 (0, 0.003, 0.01, or 0.03 mg/kg; s.c.), and memantine (0, 2.5, 5.0, or 10.0 mg/kg; i.p.), the competitive antagonist CGS 19755 (0, 5.0, 10.0, or 20.0 mg/kg; s.c.), the non-competitive NR2B subunit-selective antagonist ifenprodil (0, 1.0, 3.0, or 10.0 mg/kg; i.p), and the partial agonist D-cycloserine (0, 3.25, 15.0, or 30.0 mg/kg; s.c.). Results When an exponential model was used to describe discounting, CGS 19755 (5.0 mg/kg) increased impulsive choice without altering sensitivity to reinforcer magnitude. Conversely, ketamine (10.0 mg/kg), memantine (5.0 mg/kg), and ifenprodil (10.0 mg/kg) decreased sensitivity to reinforcer magnitude without altering impulsive choice. MK-801 and D-cycloserine did not alter delay-discounting performance, although two-way ANOVA analyses indicated D-cycloserine (15.0 mg/kg) decreased impulsive choice. Conclusions The behavioral changes observed in delay discounting following administration of NMDA receptor antagonists do not always reflect an alteration in impulsive choice. These results emphasize the utility in employing quantitative methods to assess drug effects in delay discounting. PMID:27837332

Current knowledge on biomarkers for contact sensitization and allergic contact dermatitis.

PubMed

Koppes, Sjors A; Engebretsen, Kristiane A; Agner, Tove; Angelova-Fischer, Irena; Berents, Teresa; Brandner, Johanna; Brans, Richard; Clausen, Maja-Lisa; Hummler, Edith; Jakasa, Ivone; Jurakić-Tončic, Ružica; John, Swen M; Khnykin, Denis; Molin, Sonja; Holm, Jan O; Suomela, Sari; Thierse, Hermann-Josef; Kezic, Sanja; Martin, Stefan F; Thyssen, Jacob P

2017-07-01

Contact sensitization is common and affects up to 20% of the general population. The clinical manifestation of contact sensitization is allergic contact dermatitis. This is a clinical expression that is sometimes difficult to distinguish from other types of dermatitis, for example irritant and atopic dermatitis. Several studies have examined the pathogenesis and severity of allergic contact dermatitis by measuring the absence or presence of various biomarkers. In this review, we provide a non-systematic overview of biomarkers that have been studied in allergic contact dermatitis. These include genetic variations and mutations, inflammatory mediators, alarmins, proteases, immunoproteomics, lipids, natural moisturizing factors, tight junctions, and antimicrobial peptides. We conclude that, despite the enormous amount of data, convincing specific biomarkers for allergic contact dermatitis are yet to be described. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Respiratory sensitization and allergy: Current research approaches and needs

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

Boverhof, Darrell R.; Billington, Richard; Gollapudi, B. Bhaskar

2008-01-01

There are currently no accepted regulatory models for assessing the potential of a substance to cause respiratory sensitization and allergy. In contrast, a number of models exist for the assessment of contact sensitization and allergic contact dermatitis (ACD). Research indicates that respiratory sensitizers may be identified through contact sensitization assays such as the local lymph node assay, although only a small subset of the compounds that yield positive results in these assays are actually respiratory sensitizers. Due to the increasing health concerns associated with occupational asthma and the impending directives on the regulation of respiratory sensitizers and allergens, an approachmore » which can identify these compounds and distinguish them from contact sensitizers is required. This report discusses some of the important contrasts between respiratory allergy and ACD, and highlights several prominent in vivo, in vitro and in silico approaches that are being applied or could be further developed to identify compounds capable of causing respiratory allergy. Although a number of animal models have been used for researching respiratory sensitization and allergy, protocols and endpoints for these approaches are often inconsistent, costly and difficult to reproduce, thereby limiting meaningful comparisons of data between laboratories and development of a consensus approach. A number of emerging in vitro and in silico models show promise for use in the characterization of contact sensitization potential and should be further explored for their ability to identify and differentiate contact and respiratory sensitizers. Ultimately, the development of a consistent, accurate and cost-effective model will likely incorporate a number of these approaches and will require effective communication, collaboration and consensus among all stakeholders.« less

Sources of sensitization, cross-reactions, and occupational sensitization to topical anaesthetics among general dermatology patients.

PubMed

Jussi, Liippo; Lammintausta, Kaija

2009-03-01

Contact sensitization to local anaesthetics is often from topical medicaments. Occupational sensitization to topical anaesthetics may occur in certain occupations. The aim of the study was to analyse the occurrence of contact sensitization to topical anaesthetics in general dermatology patients. Patch testing with topical anaesthetics was carried out in 620 patients. Possible sources of sensitization and the clinical histories of the patients are analysed. Positive patch test reactions to one or more topical anaesthetics were seen in 25/620 patients. Dibucaine reactions were most common (20/25), and lidocaine sensitization was seen in two patients. Six patients had reactions to ester-type and/or amide-type anaesthetics concurrently. Local preparations for perianal conditions were the most common sensitizers. One patient had developed occupational sensitization to procaine with multiple cross-reactions and with concurrent penicillin sensitization from procaine penicillin. Dibucaine-containing perianal medicaments are the major source of contact sensitization to topical anaesthetics. Although sensitization to multiple anaesthetics can be seen, cross-reactions are possible. Contact sensitization to lidocaine is not common, and possible cross-reactions should be determined when reactions to lidocaine are seen. Occupational procaine sensitization from veterinary medicaments is a risk among animal workers.

Efficacy and effectiveness of an rVSV-vectored vaccine in preventing Ebola virus disease: final results from the Guinea ring vaccination, open-label, cluster-randomised trial (Ebola Ça Suffit!).

PubMed

Henao-Restrepo, Ana Maria; Camacho, Anton; Longini, Ira M; Watson, Conall H; Edmunds, W John; Egger, Matthias; Carroll, Miles W; Dean, Natalie E; Diatta, Ibrahima; Doumbia, Moussa; Draguez, Bertrand; Duraffour, Sophie; Enwere, Godwin; Grais, Rebecca; Gunther, Stephan; Gsell, Pierre-Stéphane; Hossmann, Stefanie; Watle, Sara Viksmoen; Kondé, Mandy Kader; Kéïta, Sakoba; Kone, Souleymane; Kuisma, Eewa; Levine, Myron M; Mandal, Sema; Mauget, Thomas; Norheim, Gunnstein; Riveros, Ximena; Soumah, Aboubacar; Trelle, Sven; Vicari, Andrea S; Røttingen, John-Arne; Kieny, Marie-Paule

2017-02-04

rVSV-ZEBOV is a recombinant, replication competent vesicular stomatitis virus-based candidate vaccine expressing a surface glycoprotein of Zaire Ebolavirus. We tested the effect of rVSV-ZEBOV in preventing Ebola virus disease in contacts and contacts of contacts of recently confirmed cases in Guinea, west Africa. We did an open-label, cluster-randomised ring vaccination trial (Ebola ça Suffit!) in the communities of Conakry and eight surrounding prefectures in the Basse-Guinée region of Guinea, and in Tomkolili and Bombali in Sierra Leone. We assessed the efficacy of a single intramuscular dose of rVSV-ZEBOV (2×10 7 plaque-forming units administered in the deltoid muscle) in the prevention of laboratory confirmed Ebola virus disease. After confirmation of a case of Ebola virus disease, we definitively enumerated on a list a ring (cluster) of all their contacts and contacts of contacts including named contacts and contacts of contacts who were absent at the time of the trial team visit. The list was archived, then we randomly assigned clusters (1:1) to either immediate vaccination or delayed vaccination (21 days later) of all eligible individuals (eg, those aged ≥18 years and not pregnant, breastfeeding, or severely ill). An independent statistician generated the assignment sequence using block randomisation with randomly varying blocks, stratified by location (urban vs rural) and size of rings (≤20 individuals vs >20 individuals). Ebola response teams and laboratory workers were unaware of assignments. After a recommendation by an independent data and safety monitoring board, randomisation was stopped and immediate vaccination was also offered to children aged 6-17 years and all identified rings. The prespecified primary outcome was a laboratory confirmed case of Ebola virus disease with onset 10 days or more from randomisation. The primary analysis compared the incidence of Ebola virus disease in eligible and vaccinated individuals assigned to immediate vaccination versus eligible contacts and contacts of contacts assigned to delayed vaccination. This trial is registered with the Pan African Clinical Trials Registry, number PACTR201503001057193. In the randomised part of the trial we identified 4539 contacts and contacts of contacts in 51 clusters randomly assigned to immediate vaccination (of whom 3232 were eligible, 2151 consented, and 2119 were immediately vaccinated) and 4557 contacts and contacts of contacts in 47 clusters randomly assigned to delayed vaccination (of whom 3096 were eligible, 2539 consented, and 2041 were vaccinated 21 days after randomisation). No cases of Ebola virus disease occurred 10 days or more after randomisation among randomly assigned contacts and contacts of contacts vaccinated in immediate clusters versus 16 cases (7 clusters affected) among all eligible individuals in delayed clusters. Vaccine efficacy was 100% (95% CI 68·9-100·0, p=0·0045), and the calculated intraclass correlation coefficient was 0·035. Additionally, we defined 19 non-randomised clusters in which we enumerated 2745 contacts and contacts of contacts, 2006 of whom were eligible and 1677 were immediately vaccinated, including 194 children. The evidence from all 117 clusters showed that no cases of Ebola virus disease occurred 10 days or more after randomisation among all immediately vaccinated contacts and contacts of contacts versus 23 cases (11 clusters affected) among all eligible contacts and contacts of contacts in delayed plus all eligible contacts and contacts of contacts never vaccinated in immediate clusters. The estimated vaccine efficacy here was 100% (95% CI 79·3-100·0, p=0·0033). 52% of contacts and contacts of contacts assigned to immediate vaccination and in non-randomised clusters received the vaccine immediately; vaccination protected both vaccinated and unvaccinated people in those clusters. 5837 individuals in total received the vaccine (5643 adults and 194 children), and all vaccinees were followed up for 84 days. 3149 (53·9%) of 5837 individuals reported at least one adverse event in the 14 days after vaccination; these were typically mild (87·5% of all 7211 adverse events). Headache (1832 [25·4%]), fatigue (1361 [18·9%]), and muscle pain (942 [13·1%]) were the most commonly reported adverse events in this period across all age groups. 80 serious adverse events were identified, of which two were judged to be related to vaccination (one febrile reaction and one anaphylaxis) and one possibly related (influenza-like illness); all three recovered without sequelae. The results add weight to the interim assessment that rVSV-ZEBOV offers substantial protection against Ebola virus disease, with no cases among vaccinated individuals from day 10 after vaccination in both randomised and non-randomised clusters. WHO, UK Wellcome Trust, the UK Government through the Department of International Development, Médecins Sans Frontières, Norwegian Ministry of Foreign Affairs (through the Research Council of Norway's GLOBVAC programme), and the Canadian Government (through the Public Health Agency of Canada, Canadian Institutes of Health Research, International Development Research Centre and Department of Foreign Affairs, Trade and Development). Copyright © 2017 World Health Organization. Published by Elsevier Ltd/Inc/BV. All rights reserved. Published by Elsevier Ltd.. All rights reserved.

Transmission Scheduling and Routing Algorithms for Delay Tolerant Networks

NASA Technical Reports Server (NTRS)

Dudukovich, Rachel; Raible, Daniel E.

2016-01-01

The challenges of data processing, transmission scheduling and routing within a space network present a multi-criteria optimization problem. Long delays, intermittent connectivity, asymmetric data rates and potentially high error rates make traditional networking approaches unsuitable. The delay tolerant networking architecture and protocols attempt to mitigate many of these issues, yet transmission scheduling is largely manually configured and routes are determined by a static contact routing graph. A high level of variability exists among the requirements and environmental characteristics of different missions, some of which may allow for the use of more opportunistic routing methods. In all cases, resource allocation and constraints must be balanced with the optimization of data throughput and quality of service. Much work has been done researching routing techniques for terrestrial-based challenged networks in an attempt to optimize contact opportunities and resource usage. This paper examines several popular methods to determine their potential applicability to space networks.

Allergic contact dermatitis in preservatives: current standing and future options.

PubMed

Deza, Gustavo; Giménez-Arnau, Ana M

2017-08-01

Preservatives are well known skin sensitizers and represent one of the main causes of contact allergy. The purpose of this article is to review the current state of contact sensitization induced by preservatives and point future alternatives for products' preservation. Isothiazolinones currently are the most common preservatives responsible of contact allergy in Europe and in the United States, and although some regulatory interventions have been taken place, the current contact allergy outbreak is not yet under control. Despite the ban of methyldibromo glutaronitrile from cosmetics in Europe, sensitized patients are still diagnosed, suggesting other nonregulated sources of exposure. Sensitization rates to formaldehyde and formaldehyde-releasers are lower in Europe in comparison with the United States due to stricter regulations regarding their use. Prevalence of contact allergy to parabens has remained stable over the last decades, whereas iodopropynyl butylcarbamate is an emerging allergen with an increasing prevalence. Future alternatives for products' preservation look for a broad antimicrobial spectrum, but with a better safety profile (in terms of sensitization) than the currently available compounds. Given the high rates of sensitization reported over the last years, timely regulatory actions are urgently required for some preservatives that currently represent a concern for public health.

Timeliness of contact tracing among flight passengers for influenza A/H1N1 2009

PubMed Central

2011-01-01

Background During the initial containment phase of influenza A/H1N1 2009, close contacts of cases were traced to provide antiviral prophylaxis within 48 h after exposure and to alert them on signs of disease for early diagnosis and treatment. Passengers seated on the same row, two rows in front or behind a patient infectious for influenza, during a flight of ≥ 4 h were considered close contacts. This study evaluates the timeliness of flight-contact tracing (CT) as performed following national and international CT requests addressed to the Center of Infectious Disease Control (CIb/RIVM), and implemented by the Municipal Health Services of Schiphol Airport. Methods Elapsed days between date of flight arrival and the date passenger lists became available (contact details identified - CI) was used as proxy for timeliness of CT. In a retrospective study, dates of flight arrival, onset of illness, laboratory diagnosis, CT request and identification of contacts details through passenger lists, following CT requests to the RIVM for flights landed at Schiphol Airport were collected and analyzed. Results 24 requests for CT were identified. Three of these were declined as over 4 days had elapsed since flight arrival. In 17 out of 21 requests, contact details were obtained within 7 days after arrival (81%). The average delay between arrival and CI was 3,9 days (range 2-7), mainly caused by delay in diagnosis of the index patient after arrival (2,6 days). In four flights (19%), contacts were not identified or only after > 7 days. CI involving Dutch airlines was faster than non-Dutch airlines (P < 0,05). Passenger locator cards did not improve timeliness of CI. In only three flights contact details were identified within 2 days after arrival. Conclusion CT for influenza A/H1N1 2009 among flight passengers was not successful for timely provision of prophylaxis. CT had little additional value for alerting passengers for disease symptoms, as this information already was provided during and after the flight. Public health authorities should take into account patient delays in seeking medical advise and laboratory confirmation in relation to maximum time to provide postexposure prophylaxis when deciding to install contact tracing measures. International standardization of CT guidelines is recommended. PMID:22204494

Diagnostic delays in 537 symptomatic cases of Middle East respiratory syndrome coronavirus infection in Saudi Arabia.

PubMed

Ahmed, Anwar E

2017-09-01

Although the literature indicates that patient delays in seeking medical support for Middle East respiratory syndrome coronavirus (MERS-CoV) infections are associated with poor clinical outcomes, delays in the diagnosis itself remain poorly understood in these patients. This study aimed to determine the median time interval from symptom onset to a confirmed diagnosis and to identify the potential predictors of this interval in Saudi Arabian MERS patients. This was a retrospective study of patients with confirmed MERS who were publicly reported by the World Health Organization (WHO). Five hundred and thirty-seven symptomatic cases of MERS-CoV infection were included. The median time interval between symptom onset and confirmation of the MERS diagnosis was 4 days (interquartile range 2-7 days), ranging from 0 to 36 days. According to the negative binomial model, the unadjusted rate ratio (RR) of delays in the diagnosis was significantly higher in older patients (>65 years) (RR 1.42), non-healthcare workers (RR 1.74), patients with severe illness (RR 1.22), those with an unknown source of infection (RR 1.84), and those who had been in close contact with camels (RR 1.74). After accounting for confounders, the adjusted rate ratio (aRR) of delays in the diagnosis was independently associated with unknown source of infection (aRR 1.68) and close contact with camels (aRR 1.58). The time interval from symptom onset to diagnosis was greater in older patients, non-healthcare workers, patients with severe illness, patients with an unknown source of infection, and patients who had been in close contact with camels. The findings warrant educational interventions to raise general public awareness of the importance of early symptom notification. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Skin sensitization potency of methyl methacrylate in the local lymph node assay: comparisons with guinea-pig data and human experience.

PubMed

Betts, Catherine J; Dearman, Rebecca J; Heylings, Jon R; Kimber, Ian; Basketter, David A

2006-09-01

There is compelling evidence that contact allergens differ substantially (by 4 or 5 orders of magnitude) with respect to their inherent skin-sensitizing potency. Relative potency can now be measured effectively using the mouse local lymph node assay (LLNA) and such data form the basis of risk assessment and risk management strategies. Such determinations also facilitate distinctions being drawn between the prevalence of skin sensitization to a particular contact allergen and inherent potency. The distinction is important because chemicals that are implicated as common causes of contact allergy are not necessarily potent sensitizers. One example is provided by nickel that is undoubtedly a common cause of allergic contact dermatitis, but is a comparatively weak sensitizer in predictive tests. In an attempt to explore other examples of contact allergens where there may exist a discrepancy between prevalence and potency, we describe here analyses conducted with methyl methacrylate (MMA). Results of LLNA studies have been interpreted in the context of historical clinical data on occupational allergic contact dermatitis associated with exposure to MMA.

Corneal epithelial and aqueous humor acidification during in vivo contact lens wear in rabbits.

PubMed

Giasson, C; Bonanno, J A

1994-03-01

Based on contact lens-induced stromal acidification of the cornea, it has been suggested that the corneal epithelial and endothelial cells also become acidotic during contact lens wear. This alleged acidification may have a role in altered cell appearance and metabolism during contact lens wear. This study investigated the effects of anoxia, carbon dioxide retention, and contact lens gas transmissibility on the epithelial and aqueous humor pH in living rabbits. Epithelial intracellular pH (pHi) and aqueous humor pH were fluorophotometrically measured with a pH sensitive-dye (BCECF) during contact lens wear or exposure to various gas mixtures. Polymethylmethacrylate (PMMA) lens wear acidified epithelial cells by preventing CO2 efflux and by inducing hypoxia. Increasing lens oxygen transmissibility decreased epithelial acidification. After initiation of rigid, gas-permeable (RGP) lens wear or CO2-air exposure, pHi dropped transiently and then recovered partially. This recovery of pHi was not observed during anoxia, whether induced by PMMA lens wear or exposure to 100% N2. The aqueous humor also acidified during PMMA lens wear, a phenomenon not observed during RGP lens wear. Changes in aqueous pH were smaller, slower, and delayed when compared to their epithelial counterparts. Hypoxic contact lens wear acidifies the corneal epithelium and aqueous humor. The aqueous humor pH change indicates a probable endothelial acidification during hypoxic contact lens wear; the pH changes are caused by two separate and additive effects, CO2 retention and hypoxic acidosis. Increases in the oxygen transmissibility of the lens decrease the cellular acidosis, which might minimize cellular complications arising from contact lens wear. We estimate that a lens with an oxygen transmissibility (Dk/L) of 300 x 10(-11) (cm/sec)(ml O2/ml x mm Hg) is needed to prevent epithelial pHi changes in the open eye. In contrast, lenses with Dk/L as low as 18 x 10(-9) (cm/sec)(ml O2/ml x mm Hg) can prevent aqueous humor pH changes.

A quantitative analysis of sensitivity to the conditioned reinforcing value of terminal-link stimuli in a concurrent-chains schedule.

PubMed Central

Omino, T

1993-01-01

Pigeons were exposed to a concurrent-chains schedule in which a single variable-interval 30-s schedule was used in the initial links and fixed-time schedules were used in the terminal links. Three types of keylight conditions were used in the terminal links. In the first condition, different delays were associated with different keylight stimuli (cued condition). In the second condition, different delays were associated with the same stimulus, either a blackout (uncued blackout condition) or a white key (uncued white condition). Paired values of terminal-link fixed-time schedules differed by a constant ratio of 3:1, while the absolute value of delays was varied from 3 s to 54 s. The results showed that choice proportions for the shorter of two delays increased when the absolute size of the delays was increased for all keylight conditions. Further, the choice proportions for the shorter delay increased from the uncued blackout condition, to the uncued white condition, to the cued condition. A modified version of Fantino's (1969) delay-reduction model (expressed as a function relating the response ratio to the delay-reduction ratio) can be applied to these data by showing that sensitivity to delay reduction increased from the uncued blackout condition, to the uncued white condition, to the cued condition. Thus, the present study demonstrated that a modified version of the delay-reduction model can be used to assess quantitative differences in the terminal-link keylight condition in terms of sensitivity to delay reduction (i.e., the conditioned reinforcing value of the terminal-link keylight stimuli). PMID:8283150

Autonomous Adaptation and Collaboration of Unmanned Vehicles for Tracking Submerged Contacts

DTIC Science & Technology

2012-06-01

filter: CRS RANGE REPORT =”name=archie,range=23.4,target= jackal ,time=2342551.213” • Line 8: ping wait is the time delay between range pulses. • Line 13: rn...uFldContactRangeSensor Settings 1: ProcessConfig = uFldContactRangeSensor 2: { 3: AppTick = 4 4: CommsTick = 4 5: 6: reply distance = jackal = 50 7: reach distance...REPORT = CRS RANGE REPORT 8: MY SHIP = archie 9: MY FRIEND = betty 10: MY CONTACT = jackal 11: MY BEST GUESS = besttarget 12: MY AVG GUESS = avgtarget 13

Crepidula Slipper Limpets Alter Sex Change in Response to Physical Contact with Conspecifics.

PubMed

Carrillo-Baltodano, Allan; Collin, Rachel

2015-12-01

Chemical signaling, especially signaling with waterborne cues, is an important mode of communication between conspecifics of aquatic organisms. Although conspecific associations play an important role in sex allocation of sequential hermaphroditic slipper limpets, the mode of signaling is unknown. We tested the hypothesis that the effects of conspecifics on animal size and time of sex change in the tropical slipper limpet Crepidula cf. marginalis are mediated by waterborne cues. In our experiment, pairs of snails (one small and one large) were kept in cups, either together or partitioned off with fine or coarse mesh, or partitioned, but switched from side to side to allow contact with the cup mate's pedal mucus. The larger snails that were allowed contact with the smaller companions grew faster, and generally changed sex sooner, than did the larger snails in the barrier treatments, which allowed no physical contact. The smaller snails that were allowed contact with the larger cup mate delayed sex change compared to those separated from their cup mates. We were, therefore, able to reject the hypothesis that waterborne cues mediate communication between these snails. Our results suggest that the cue that affects size and time to sex change requires some kind of physical interaction that is lost when the snails are separated. Furthermore, contact with another snail's pedal mucus does not compensate for the loss of physical contact. Since males often attach to the shell of larger females, direct contact may mediate this kind of physical interaction via positional information, physical stimulation, or contact-based chemical communication. Whatever the cue, contact with conspecifics influences both partners, resulting in, surprisingly, a higher growth rate in the larger animal and delayed sex change in the smaller animal. © 2015 Marine Biological Laboratory.

Contact Graph Routing Enhancements Developed in ION for DTN

NASA Technical Reports Server (NTRS)

Segui, John S.; Burleigh, Scott

2013-01-01

The Interplanetary Overlay Network (ION) software suite is an open-source, flight-ready implementation of networking protocols including the Delay/Disruption Tolerant Networking (DTN) Bundle Protocol (BP), the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol (CFDP), and many others including the Contact Graph Routing (CGR) DTN routing system. While DTN offers the capability to tolerate disruption and long signal propagation delays in transmission, without an appropriate routing protocol, no data can be delivered. CGR was built for space exploration networks with scheduled communication opportunities (typically based on trajectories and orbits), represented as a contact graph. Since CGR uses knowledge of future connectivity, the contact graph can grow rather large, and so efficient processing is desired. These enhancements allow CGR to scale to predicted NASA space network complexities and beyond. This software improves upon CGR by adopting an earliest-arrival-time cost metric and using the Dijkstra path selection algorithm. Moving to Dijkstra path selection also enables construction of an earliest- arrival-time tree for multicast routing. The enhancements have been rolled into ION 3.0 available on sourceforge.net.

KC-46 Tanker Modernization: Delivery of First Fully Capable Aircraft Has Been Delayed over One Year and Additional Delays Are Possible

DTIC Science & Technology

2017-03-01

delays. As shown, the remaining schedule was modified to allow Boeing to deliver the first 18 aircraft and pods separately by October 2018, 14...testing. Among other things, Boeing is contractually required to deliver a total of 18 aircraft and 9 wing air refueling pod sets by August 2017...Parameters and System Attributes and Status of Technical Performance Capabilities 18 Appendix II GAO Contact and Staff Acknowledgments 20 Related

Determinants of choice, and vulnerability and recovery in addiction.

PubMed

Lamb, R J; Maguire, David R; Ginsburg, Brett C; Pinkston, Jonathan W; France, Charles P

2016-06-01

Addiction may be viewed as choice governed by competing contingencies. One factor impacting choice, particularly as it relates to addiction, is sensitivity to delayed rewards. Discounting of delayed rewards influences addiction vulnerability because of competition between relatively immediate gains of drug use, e.g. intoxication, versus relatively remote gains of abstinence, e.g. family stability. Factors modifying delay sensitivity can be modeled in the laboratory. For instance, increased delay sensitivity can be similarly observed in adolescent humans and non-human animals. Similarly, genetic factors influence delay sensitivity in humans and animals. Recovery from addiction may also be viewed as choice behavior. Thus, reinforcing alternative behavior facilitates recovery because reinforcing alternative behavior decreases the frequency of using drugs. How reinforcing alternative behavior influences recovery can also be modeled in the laboratory. For instance, relapse risk decreases as abstinence duration increases, and this decreasing risk can be modeled in animals using choice procedures. In summary, addiction in many respects can be conceptualized as a problem of choice. Animal models of choice disorders stand to increase our understanding of the core processes that establish and maintain addiction and serve as a proving ground for development of novel treatments. Copyright © 2016 Elsevier B.V. All rights reserved.

Sensitivity and specificity of the 3-item memory test in the assessment of post traumatic amnesia.

PubMed

Andriessen, Teuntje M J C; de Jong, Ben; Jacobs, Bram; van der Werf, Sieberen P; Vos, Pieter E

2009-04-01

To investigate how the type of stimulus (pictures or words) and the method of reproduction (free recall or recognition after a short or a long delay) affect the sensitivity and specificity of a 3-item memory test in the assessment of post traumatic amnesia (PTA). Daily testing was performed in 64 consecutively admitted traumatic brain injured patients, 22 orthopedically injured patients and 26 healthy controls until criteria for resolution of PTA were reached. Subjects were randomly assigned to a test with visual or verbal stimuli. Short delay reproduction was tested after an interval of 3-5 minutes, long delay reproduction was tested after 24 hours. Sensitivity and specificity were calculated over the first 4 test days. The 3-word test showed higher sensitivity than the 3-picture test, while specificity of the two tests was equally high. Free recall was a more effortful task than recognition for both patients and controls. In patients, a longer delay between registration and recall resulted in a significant decrease in the number of items reproduced. Presence of PTA is best assessed with a memory test that incorporates the free recall of words after a long delay.

Determinants of choice, and vulnerability and recovery in addiction

PubMed Central

Lamb, R.J.; Maguire, David R.; Ginsburg, Brett C.; Pinkston, Jonathan W.; France, Charles P.

2016-01-01

Addiction may be viewed as choice governed by competing contingencies. One factor impacting choice, particularly as it relates to addiction, is sensitivity to delayed rewards. Discounting of delayed rewards influences addiction vulnerability because of competition between relatively immediate gains of drug use, e.g. intoxication, versus relatively remote gains of abstinence, e.g. family stability. Factors modifying delay sensitivity can be modeled in the laboratory. For instance, increased delay sensitivity can be similarly observed in adolescent humans and non-human animals. Similarly, genetic factors influence delay sensitivity in humans and animals. Recovery from addiction may also be viewed as choice behavior. Thus, reinforcing alternative behavior facilitates recovery because reinforcing alternative behavior decreases the frequency of using drugs. How reinforcing alternative behavior influences recovery can also be modeled in the laboratory. For instance, relapse risk decreases as abstinence duration increases, and this decreasing risk can be modeled in animals using choice procedures. In summary, addiction in many respects can be conceptualized as a problem of choice. Animal models of choice disorders stand to increase our understanding of the core processes that establish and maintain addiction and serve as a proving ground for development of novel treatments. PMID:27083500

Delay discounting, risk-taking, and rejection sensitivity among individuals with Internet and Video Gaming Disorders.

PubMed

Weinstein, Aviv; Abu, Hodaya Ben; Timor, Ayelet; Mama, Yaniv

2016-12-01

Background and aims There is a previous evidence for impulsivity in individuals with Internet and Video Gaming Disorders. The aim of this study was to examine whether Internet and video game addictions are associated with experiential delay discounting, risk-taking, and sensitivity to social rejection using computerized tasks and questionnaires. Methods Twenty participants (mean age 24, SD = 1.55) with high score on the Problematic Online Gaming Questionnaire (POGQ) were compared with 20 participants (mean age 24.8, SD = 1.34) with low score on the POGQ. They performed on computerized Balloon Analog Risk Task and Experiential Delay discounting Task (EDT), and filled in the sensitivity to social rejection questionnaire. Results Participants with high POGQ scores had lower measures of delay discounting, higher measures of risk-taking, and higher measures of sensitivity to social rejection compared with participants with low POGQ scores. Discussion The results of this study support the previous evidence of risk-taking and provide new evidence for difficulties in delay discounting and sensitivity to social rejection among those who score high on Internet and video games. Conclusions The results suggest that Internet- and video game-addicted individuals seek immediate gratification and cannot wait for later reward. Furthermore, these individuals spend time in the virtual world, where they feel safe, and avoid social interactions presumably due to fears of social rejection.

Fabrication and icing property of superhydrophilic and superhydrophobic aluminum surfaces derived from anodizing aluminum foil in a sodium chloride aqueous solution

NASA Astrophysics Data System (ADS)

Song, Meirong; Liu, Yuru; Cui, Shumin; Liu, Long; Yang, Min

2013-10-01

An aluminum foil with a rough surface was first prepared by anodic treatment in a neutral aqueous solution with the help of pitting corrosion of chlorides. First, the hydrophobic Al surface (contact angle around 79°) became superhydrophilic (contact angle smaller than 5°) after the anodizing process. Secondly, the superhydrophilic Al surface became superhydrophobic (contact angle larger than 150°) after being modified by oleic acid. Finally, the icing property of superhydrophilic, untreated, and superhydrophobic Al foils were investigated in a refrigerated cabinet at -12 °C. The mean total times to freeze a water droplet (6 μL) on the three foils were 17 s, 158 s and 1604 s, respectively. Thus, the superhydrophilic surface accelerates the icing process, while the superhydrophobic surface delays the process. The main reason for this transition might mainly result from the difference of the contact area of the water droplet with Al substrate: the increase in contact area with Al substrate will accelerate the heat conduct process, as well as the icing process; the decrease in contact area with Al substrate will delay the heat conduct process, as well as the icing process. Compared to the untreated Al foil, the contact area of the water droplet with the Al substrate was higher on superhydrophilic surface and smaller on the superhydrophobic surface, which led to the difference of the heat transfer time as well as the icing time.

Time domain diffuse Raman spectrometer based on a TCSPC camera for the depth analysis of diffusive media.

PubMed

Konugolu Venkata Sekar, S; Mosca, S; Tannert, S; Valentini, G; Martelli, F; Binzoni, T; Prokazov, Y; Turbin, E; Zuschratter, W; Erdmann, R; Pifferi, A

2018-05-01

We present a time domain diffuse Raman spectrometer for depth probing of highly scattering media. The system is based on, to the best of our knowledge, a novel time-correlated single-photon counting (TCSPC) camera that simultaneously acquires both spectral and temporal information of Raman photons. A dedicated non-contact probe was built, and time domain Raman measurements were performed on a tissue mimicking bilayer phantom. The fluorescence contamination of the Raman signal was eliminated by early time gating (0-212 ps) the Raman photons. Depth sensitivity is achieved by time gating Raman photons at different delays with a gate width of 106 ps. Importantly, the time domain can provide time-dependent depth sensitivity leading to a high contrast between two layers of Raman signal. As a result, an enhancement factor of 2170 was found for our bilayer phantom which is much higher than the values obtained by spatial offset Raman spectroscopy (SORS), frequency offset Raman spectroscopy (FORS), or hybrid FORS-SORS on a similar phantom.

Delay discounting of qualitatively different reinforcers in rats.

PubMed

Calvert, Amanda L; Green, Leonard; Myerson, Joel

2010-03-01

Humans discount larger delayed rewards less steeply than smaller rewards, whereas no such magnitude effect has been observed in rats (and pigeons). It remains possible that rats' discounting is sensitive to differences in the quality of the delayed reinforcer even though it is not sensitive to amount. To evaluate this possibility, Experiment 1 examined discounting of qualitatively different food reinforcers: highly preferred versus nonpreferred food pellets. Similarly, Experiment 2 examined discounting of highly preferred versus nonpreferred liquid reinforcers. In both experiments, an adjusting-amount procedure was used to determine the amount of immediate reinforcer that was judged to be of equal subjective value to the delayed reinforcer. The amount and quality of the delayed reinforcer were varied across conditions. Discounting was well described by a hyperbolic function, but no systematic effects of the quantity or the quality of the delayed reinforcer were observed.

Cell contact regulates neuroblast formation in the Caenorhabditis elegans lateral epidermis.

PubMed

Austin, J; Kenyon, C

1994-02-01

A single line of epidermal seam cells lies along each side of the nematode C. elegans. During normal development, one of these cells, V5, produces a neuroblast that will give rise to a sensory structure, the postdeirid. If seam cells located either anterior or posterior to V5 are ablated however, this neuroblast formation is blocked. Because of this requirement for the presence of adjacent seam cells, we have asked whether V5's ability to produce a neuroblast depends on direct contact with its seam cell neighbors. We find that direct contact between seam cells is required for commitment to neuroblast production. Seam cells lose and reform their contacts with each other as they go through rounds of cell division during larval development. Signaling required for neuroblast formation occurs when the seam cells make contact after their first round of division. If this contact is prevented, no neuroblast is made; when it is delayed, the time of signaling is also delayed. The characteristics of these signals suggest that a seam cell must be part of a continuous epithelium in order to develop normally and that signaling may occur via a cell recognition/cell adhesion pathway. The effect of seam cell ablations on neuroblast formation is altered in mab-5(-) animals, suggesting that this HOM-C gene is part of the pathway by which seam cell signaling controls the decision to make a postdeirid neuroblast.

Differential gene expression responses distinguish contact and respiratory sensitizers and nonsensitizing irritants in the local lymph node assay.

PubMed

Adenuga, David; Woolhiser, Michael R; Gollapudi, B Bhaskar; Boverhof, Darrell R

2012-04-01

Genomic approaches have the potential to enhance the specificity and predictive accuracy of existing toxicology endpoints, including those for chemical sensitization. The present study was conducted to determine whether gene expression responses can distinguish contact sensitizers (1-chloro-2,4-dinitrobenzene [DNCB] and hexyl cinnamic aldehyde [HCA]), respiratory sensitizers (ortho-phthalaldehyde and trimellitic anhydride [TMA]), and nonsensitizing irritants (methyl salicylate [MS] and nonanoic acid [NA]) in the local lymph node assay (LLNA). Female Balb/c mice received doses of each chemical as per the standard LLNA dosing regimen on days 1, 2, and 3. Auricular lymph nodes were analyzed for tritiated thymidine ((3)HTdR) incorporation on day 6 and for gene expression responses on days 6 and 10. All chemicals induced dose-dependent increases in stimulation index, which correlated strongly with the number of differentially expressed genes. A majority of genes modulated by the irritants were similarly altered by the sensitizers, consistent with the irritating effects of the sensitizers. However, a select number of responses involved with immune-specific functions, such as dendritic cell activation, were unique to the sensitizers and may offer the ability to distinguish sensitizers from irritants. Genes for the mast cell proteases 1 and 8, Lgals7, Tim2, Aicda, Il4, and Akr1c18 were more strongly regulated by respiratory sensitizers compared with contact sensitizers and may represent potential biomarkers for discriminating between contact and respiratory sensitizers. Collectively, these data suggest that gene expression responses may serve as useful biomarkers to distinguish between respiratory and contact sensitizers and nonsensitizing irritants in the LLNA.

Determinants of choice for pigeons and humans on concurrent-chains schedules of reinforcement.

PubMed

Belke, T W; Pierce, W D; Powell, R A

1989-09-01

Concurrent-chains schedules of reinforcement were arranged for humans and pigeons. Responses of humans were reinforced with tokens exchangeable for money, and key pecks of 4 birds were reinforced with food. Variable-interval 30-s and 40-s schedules operated in the terminal links of the chains. Condition 1 exposed subjects to variable-interval 90-s and variable-interval 30-s initial links, respectively. Conditions 2 and 3 arranged equal initial-link schedules of 40 s or 120 s. Experimental conditions tested the descriptive adequacy of five equations: reinforcement density, delay reduction, modified delay reduction, matching and maximization. Results based on choice proportions and switch rates during the initial links showed that pigeons behaved in accord with delay-reduction models, whereas humans maximized overall rate of reinforcement. As discussed by Logue and associates in self-control research, different types of reinforcement may affect sensitivity to delay differentially. Pigeons' responses were reinforced with food, a reinforcer that is consumable upon presentation. Humans' responses were reinforced with money, a reinforcer exchanged for consumable reinforcers after it was earned. Reinforcers that are immediately consumed may generate high sensitivity to delay and behavior described as delay reduction. Reinforces with longer times to consumption may generate low sensitivity to delay and behavior that maximizes overall payoff.

Association between atopic dermatitis and contact sensitization: A systematic review and meta-analysis.

PubMed

Hamann, Carsten R; Hamann, Dathan; Egeberg, Alexander; Johansen, Jeanne D; Silverberg, Jonathan; Thyssen, Jacob P

2017-07-01

It is unclear whether patients with atopic dermatitis (AD) have an altered prevalence or risk for contact sensitization. Increased exposure to chemicals in topical products together with impaired skin barrier function suggest a higher risk, whereas the immune profile suggests a lower risk. To perform a systematic review and meta-analysis of the association between AD and contact sensitization. The PubMed/Medline, Embase, and Cochrane databases were searched for articles that reported on contact sensitization in individuals with and without AD. The literature search yielded 10,083 citations; 417 were selected based on title and abstract screening and 74 met inclusion criteria. In a pooled analysis, no significant difference in contact sensitization between AD and controls was evident (random effects model odds ratio [OR] = 0.891; 95% confidence interval [CI] = 0.771-1.03). There was a positive correlation in studies that compared AD patients with individuals from the general population (OR 1.50, 95% CI 1.23-1.93) but an inverse association when comparing with referred populations (OR 0.753, 95% CI 0.63-0.90). Included studies used different tools to diagnose AD and did not always provide information on current or past disease. Patch test allergens varied between studies. No overall relationship between AD and contact sensitization was found. We recommend that clinicians consider patch testing AD patients when allergic contact dermatitis is suspected. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Sensitivity improvements of a resonance-based tactile sensor.

PubMed

Murayama, Yoshinobu; Lindahl, Olof A

2017-02-01

Resonance-based contact-impedance measurement refers to the application of resonance sensors based on the measurement of the changes in the resonance curve of an ultrasonic resonator in contact with a surface. The advantage of the resonance sensor is that it is very sensitive to small changes in the contact impedance. A sensitive micro tactile sensor (MTS) was developed, which measured the elasticity of soft living tissues at the single-cell level. In the present paper, we studied the method of improving the touch and stiffness sensitivity of the MTS. First, the dependence of touch sensitivity in relation to the resonator length was studied by calculating the sensitivity coefficient at each length ranging from 9 to 40 mm. The highest touch sensitivity was obtained with a 30-mm-long glass needle driven at a resonance frequency of 100 kHz. Next, the numerical calculation of contact impedance showed that the highest stiffness sensitivity was achieved when the driving frequency was 100 kHz and the contact-tip diameter of the MTS was 10 μm. The theoretical model was then confirmed experimentally using a phase-locked-loop-based digital feedback oscillation circuit. It was found that the developed MTS, whose resonant frequency was 97.030 kHz, performed with the highest sensitivity of 53.2 × 10 6  Hz/N at the driving frequency of 97.986 kHz, i.e. the highest sensitivity was achieved at 956 Hz above the resonant frequency.

Self-heating and scaling of thin body transistors

NASA Astrophysics Data System (ADS)

Pop, Eric

The most often cited technological roadblock of nanoscale electronics is the "power problem," i.e. power densities and device temperatures reaching levels that will prevent their reliable operation. Technology roadmap (ITRS) requirements are expected to lead to more heat dissipation problems, especially with the transition towards geometrically confined device geometries (SOI, FinFET, nanowires), and new materials with poor thermal properties. This work examines the physics of heat generation in silicon, and in the context of nanoscale CMOS transistors. A new Monte Carlo code (MONET) is introduced which uses analytic descriptions of both the electron bands and the phonon dispersion. Detailed heat generation statistics are computed in bulk and strained silicon, and within simple device geometries. It is shown that non-stationary transport affects heat generation near strongly peaked electric fields, and that self-heating occurs almost entirely in the drain end of short, quasi-ballistic devices. The dissipated power is spectrally distributed between the (slow) optical and (fast) acoustic phonon modes approximately by a ratio of two to one. In addition, this work explores the limits of device design and scaling from an electrical and thermal point of view. A self-consistent electro-thermal compact model for thin-body (SOI, GOI) devices is introduced for calculating operating temperature, saturation current and intrinsic gate delay. Self-heating is sensitive to several device parameters, such as raised source/drain height and material boundary thermal resistance. An experimental method is developed for extracting via/contact thermal resistance from electrical measurements. The analysis suggests it is possible to optimize device geometry in order to simultaneously minimize operating temperature and intrinsic gate delay. Electro-thermal contact and device design are expected to become more important with continued scaling.

[Study of tuberculosis outbreaks reported in Catalonia, 1998-2002].

PubMed

Bran, Carlos M; Caylá, Joan A; Domínguez, Angela; Camps, Neus; Godoy, Pere; Orcau, Angels; Barrabeig, Irene; Alcaide, José; Altet, Neus; Alvarez, Pep

2006-06-01

To analyze the characteristics of tuberculosis outbreaks declared under vigilance programs in Catalonia. Descriptive study of outbreaks from 1998 through 2002 for which reports were available. An outbreak was defined as 3 or more associated cases appearing within a year. For 2 health care regions, outbreaks for which there were full surveillance reports with contact tracing were compared to outbreaks identified but which had not been fully reported. Twenty-seven outbreaks were analyzed. Nineteen (70%) occurred within families. A total of 22 outbreaks were declared upon identification of the true index case and 5 upon detection of secondary cases. The mean annual incidence of outbreaks was 0.40/100,100 inhabitants. Most cases were in males 16 to 40 years of age and involved cavitary lesions and a clinically significant diagnostic delay. Twenty-seven outbreaks caused 69 secondary cases. A longer diagnostic delay was seen to correspond to a larger number of secondary cases (P=.08). In the 2 health care regions analyzed, full surveillance reports with contact tracing were issued for 2 of the 14 outbreaks detected (14.4%). Tuberculosis outbreaks are common but investigative follow-up is scarce. The size of the outbreak is related to the length of diagnostic delay. Rapid diagnosis, contact tracing, and the issuance of a public health report should be priorities in all outbreaks detected.

Comparison of bandwidths in the inferior colliculus and the auditory nerve. II: Measurement using a temporally manipulated stimulus.

PubMed

Mc Laughlin, Myles; Chabwine, Joelle Nsimire; van der Heijden, Marcel; Joris, Philip X

2008-10-01

To localize low-frequency sounds, humans rely on an interaural comparison of the temporally encoded sound waveform after peripheral filtering. This process can be compared with cross-correlation. For a broadband stimulus, after filtering, the correlation function has a damped oscillatory shape where the periodicity reflects the filter's center frequency and the damping reflects the bandwidth (BW). The physiological equivalent of the correlation function is the noise delay (ND) function, which is obtained from binaural cells by measuring response rate to broadband noise with varying interaural time delays (ITDs). For monaural neurons, delay functions are obtained by counting coincidences for varying delays across spike trains obtained to the same stimulus. Previously, we showed that BWs in monaural and binaural neurons were similar. However, earlier work showed that the damping of delay functions differs significantly between these two populations. Here, we address this paradox by looking at the role of sensitivity to changes in interaural correlation. We measured delay and correlation functions in the cat inferior colliculus (IC) and auditory nerve (AN). We find that, at a population level, AN and IC neurons with similar characteristic frequencies (CF) and BWs can have different responses to changes in correlation. Notably, binaural neurons often show compression, which is not found in the AN and which makes the shape of delay functions more invariant with CF at the level of the IC than at the AN. We conclude that binaural sensitivity is more dependent on correlation sensitivity than has hitherto been appreciated and that the mechanisms underlying correlation sensitivity should be addressed in future studies.

Paramountcy, Family Rights and Contested Adoption: Does Contact with Birth Relatives Balance the Scales?

ERIC Educational Resources Information Center

MacDonald, Mandi; McLoughlin, Priscilla

2016-01-01

This article combines practitioner insight and research evidence to chart how principles of partnership and paramountcy have led to birth family contact becoming the expected norm following contested adoption from care in Northern Ireland. The article highlights how practice has adapted to the delay in proposed reforms to adoption legislation…

43 CFR 2.11 - Why is it important to send my request to the right office?

Code of Federal Regulations, 2010 CFR

2010-10-01

... request to the FOIA Contact at the appropriate bureau office may delay processing, because the time limit... received by the bureau office where the records are maintained. The processing of your request may be delayed if you send it to the Secretary of the Interior (or other high-level officials), the Office of...

Ultraviolet irradiation of herpes simplex virus (type 1): delayed transcription and comparative sensitivites of virus functions.

PubMed

Eglin, R P; Gugerli, P; Wildy, P

1980-07-01

The delay in the replication of herpes simplex virus surviving u.v. irradiation occurs after the uncoating of virus, as judged by sensitivity to DNase. It occurs before translation, judged by the kinetics of appearance of various virus-specific proteins, and before transcription, judged by the detection of virus-specific RNA by in situ hybridization. Since the delays in both transcription and translation are reversed by photoreactivation, the simplest hypothesis is that pyrimidine dimers directly obstruct transcription;unless these are broken by photoreactivating enzymes, there will be transcriptional delay until reactivating processes have repaired the lesion. The u.v. sensitivities of the abilities to induce various enzymes (thymidine kinase, DNase and DNA polymerase) were only about four times less than that of infectivity. The The ability to induce the three enzymes was three times less sensitive than that of the structural antigen (Band II).

Magnetic Field Effects on Triplet-Triplet Annihilation in Solutions: Modulation of Visible/NIR Luminescence.

PubMed

Mani, Tomoyasu; Vinogradov, Sergei A

2013-08-06

Photon upconversion based on sensitized triplet-triplet annihilation (TTA) presents interest for such areas as photovoltaics and imaging. Usually energy upconversion is observed as p -type delayed fluorescence from molecules whose triplet states are populated via energy transfer from a suitable triplet donor, followed by TTA. Magnetic field effects (MFE) on delayed fluorescence in molecular crystals are well known; however, there exist only a few examples of MFE on TTA in solutions, and all of them are limited to UV-emitting materials. Here we present MFE on TTA-mediated visible and near infrared (NIR) emission, sensitized by far-red absorbing metalloporphyrins in solutions at room temperature. In addition to visible delayed fluorescence from annihilator, we also observed NIR emission from the sensitizer, occurring as a result of triplet-triplet energy transfer back from annihilator, termed "delayed phosphorescence". This emission also exhibits MFE, but opposite in sign to the annihilator fluorescence.

Delayed diagnosis of an isolated posterolateral corner injury: a case report

PubMed Central

Welsh, Patrick; DeGraauw, Christopher; Whitty, David

2016-01-01

Introduction: Isolated injuries to the posterolateral corner of the knee are a rare and commonly missed injury associated with athletic trauma, motor vehicle accidents, and falls. Delayed or missed diagnoses can negatively impact patient prognosis, contributing to residual instability, chronic pain, and failure of surgical repair to other ligaments. Case Presentation: A 44-year-old male CrossFit athlete presented with a history of two non-contact hyperextension injuries to his left knee while walking on ice. The only positive finding was the Dial Test at 30 degrees of knee flexion, indicative of an isolated posterolateral corner injury. After a delay in diagnosis, the patient underwent a reconstruction of the posterolateral corner and subsequent rehabilitation. Early recognition of this injury is important as this can affect the prognosis and activities of daily living of the patient. Summary: This case will discuss the clinical presentation, diagnostic procedures, and management of an isolated posterolateral corner injury and highlight the importance of early recognition and referrals from primary contact healthcare practitioners. PMID:28065990

Delayed diagnosis of an isolated posterolateral corner injury: a case report.

PubMed

Welsh, Patrick; DeGraauw, Christopher; Whitty, David

2016-12-01

Isolated injuries to the posterolateral corner of the knee are a rare and commonly missed injury associated with athletic trauma, motor vehicle accidents, and falls. Delayed or missed diagnoses can negatively impact patient prognosis, contributing to residual instability, chronic pain, and failure of surgical repair to other ligaments. A 44-year-old male CrossFit athlete presented with a history of two non-contact hyperextension injuries to his left knee while walking on ice. The only positive finding was the Dial Test at 30 degrees of knee flexion, indicative of an isolated posterolateral corner injury. After a delay in diagnosis, the patient underwent a reconstruction of the posterolateral corner and subsequent rehabilitation. Early recognition of this injury is important as this can affect the prognosis and activities of daily living of the patient. This case will discuss the clinical presentation, diagnostic procedures, and management of an isolated posterolateral corner injury and highlight the importance of early recognition and referrals from primary contact healthcare practitioners.

PERIPUBERTAL DI (2-ETHYLHEXYL) PHTHALATE EXPOSURE INHIBITS ANDROGEN SENSITIVE TISSUE DEVELOPMENT AND DELAYS PUBERTY IN MALE SPRAGUE-DAWLEY RATS

EPA Science Inventory

PERIPUBERTAL DI (2-ETHYLHEXYL) PHTHALATE EXPOSURE INHIBITS ANDROGEN SENSITIVE TISSUE DEVELOPMENT AND DELAYS PUBERTY IN MALE SPRAGUE-DAWLEY RATS

Nigel Noriega, Jonathan Furr, Christy Lambright, Vickie Wilson, L. Earl Gray Jr.

The plasticizer Di (2-ethylhexyl) phtha...

Fibroblast-induced switching to the mesenchymal-like phenotype and PI3K/mTOR signaling protects melanoma cells from BRAF inhibitors

PubMed Central

Seip, Kotryna; Nygaard, Vigdis; Haugen, Mads H.; Engesæter, Birgit Ø.; Mælandsmo, Gunhild M.; Prasmickaite, Lina

2016-01-01

The knowledge on how tumor-associated stroma influences efficacy of anti-cancer therapy just started to emerge. Here we show that lung fibroblasts reduce melanoma sensitivity to the BRAF inhibitor (BRAFi) vemurafenib only if the two cell types are in close proximity. In the presence of fibroblasts, the adjacent melanoma cells acquire de-differentiated mesenchymal-like phenotype. Upon treatment with BRAFi, such melanoma cells maintain high levels of phospho ribosomal protein S6 (pS6), i.e. active mTOR signaling, which is suppressed in the BRAFi sensitive cells without stromal contacts. Inhibitors of PI3K/mTOR in combination with BRAFi eradicate pS6high cell subpopulations and potentiate anti-cancer effects in melanoma protected by the fibroblasts. mTOR and BRAF co-inhibition also delayed the development of early-stage lung metastases in vivo. In conclusion, we demonstrate that upon influence from fibroblasts, melanoma cells undergo a phenotype switch to the mesenchymal state, which can support PI3K/mTOR signaling. The lost sensitivity to BRAFi in such cells can be overcome by co-targeting PI3K/mTOR. This knowledge could be explored for designing BRAFi combination therapies aiming to eliminate both stroma-protected and non-protected counterparts of metastases. PMID:26918352

The tremble dance of honey bees can be caused by hive-external foraging experience.

PubMed

Thom, Corinna

2003-07-01

The tremble dance of honey bee nectar foragers is part of the communication system that regulates a colony's foraging efficiency. A forager that returns to the hive with nectar, but then experiences a long unloading delay because she has difficulty finding a nectar receiver bee, will perform a tremble dance to recruit additional nectar receiver bees. A forager that experiences a short unloading delay will perform a waggle dance to recruit more nectar foragers. A long unloading delay was until now the only known cause of tremble dancing. However, several studies suggested that factors at the food source may also cause tremble dancing. Here I test whether one of these factors, crowding of nectar foragers at the food source, stimulates tremble dancing because it causes long unloading delays. To do so, I increased the density of nectar foragers at a food source by suddenly reducing the size of an artificial feeder, and recorded the unloading delay experienced by each forager, as well as the dance she performed, if any. A forager's unloading delay was measured as the time interval between entering the hive and either (1) the first unloading contact with a nectar receiver bee, or (2) the start of the first dance, if dancing began before the first unloading contact. I also recorded the unloading delays and dances of nectar foragers that returned from natural food sources. The results show that crowding of nectar foragers at the food source increases the probability of tremble dancing, but does not cause long unloading delays, and that tremble dancers that foraged at natural food sources also often have short unloading delays. When the cause of the tremble dance is not a low supply of nectar receiver bees, the tremble dance may have a function in addition to the recruitment of nectar receiver bees.

Impact of scaling voltage and size on the performance of Side-contacted Field Effect Diode

NASA Astrophysics Data System (ADS)

Touchaei, Behnam Jafari; Manavizadeh, Negin

2018-05-01

Side-contacted Fild Effect Diode (S-FED), with low leakage current and high Ion/Ioff ratio, has been recently introduced to suppress short channel effects in nanoscale regime. The voltage and size scalability of S-FEDs and effects on the power consumption, propagation delay time, and power delay product have been studied in this article. The most attractive properties are related to channel length to channel thickness ratio in the S-FED which reduces in comparison with MOSFET significantly, while gates control over the channel improve and the off-state current reduces dramatically. This promising advantage is not only capable to improve important S-FED's characteristics such as subthreshold slope but also eliminate Latch-up and floating body effect.

Adaptive Information Dissemination Control to Provide Diffdelay for the Internet of Things.

PubMed

Liu, Xiao; Liu, Anfeng; Huang, Changqin

2017-01-12

Applications running on the Internet of Things, such as the Wireless Sensor and Actuator Networks (WSANs) platform, generally have different quality of service (QoS) requirements. For urgent events, it is crucial that information be reported to the actuator quickly, and the communication cost is the second factor. However, for interesting events, communication costs, network lifetime and time all become important factors. In most situations, these different requirements cannot be satisfied simultaneously. In this paper, an adaptive communication control based on a differentiated delay (ACCDS) scheme is proposed to resolve this conflict. In an ACCDS, source nodes of events adaptively send various searching actuators routings (SARs) based on the degree of sensitivity to delay while maintaining the network lifetime. For a delay-sensitive event, the source node sends a large number of SARs to actuators to identify and inform the actuators in an extremely short time; thus, action can be taken quickly but at higher communication costs. For delay-insensitive events, the source node sends fewer SARs to reduce communication costs and improve network lifetime. Therefore, an ACCDS can meet the QoS requirements of different events using a differentiated delay framework. Theoretical analysis simulation results indicate that an ACCDS provides delay and communication costs and differentiated services; an ACCDS scheme can reduce the network delay by 11.111%-53.684% for a delay-sensitive event and reduce the communication costs by 5%-22.308% for interesting events, and reduce the network lifetime by about 28.713%.

Adaptive Information Dissemination Control to Provide Diffdelay for the Internet of Things

PubMed Central

Liu, Xiao; Liu, Anfeng; Huang, Changqin

2017-01-01

Applications running on the Internet of Things, such as the Wireless Sensor and Actuator Networks (WSANs) platform, generally have different quality of service (QoS) requirements. For urgent events, it is crucial that information be reported to the actuator quickly, and the communication cost is the second factor. However, for interesting events, communication costs, network lifetime and time all become important factors. In most situations, these different requirements cannot be satisfied simultaneously. In this paper, an adaptive communication control based on a differentiated delay (ACCDS) scheme is proposed to resolve this conflict. In an ACCDS, source nodes of events adaptively send various searching actuators routings (SARs) based on the degree of sensitivity to delay while maintaining the network lifetime. For a delay-sensitive event, the source node sends a large number of SARs to actuators to identify and inform the actuators in an extremely short time; thus, action can be taken quickly but at higher communication costs. For delay-insensitive events, the source node sends fewer SARs to reduce communication costs and improve network lifetime. Therefore, an ACCDS can meet the QoS requirements of different events using a differentiated delay framework. Theoretical analysis simulation results indicate that an ACCDS provides delay and communication costs and differentiated services; an ACCDS scheme can reduce the network delay by 11.111%–53.684% for a delay-sensitive event and reduce the communication costs by 5%–22.308% for interesting events, and reduce the network lifetime by about 28.713%. PMID:28085097

Bilateral control of master-slave manipulators with constant time delay.

PubMed

Forouzantabar, A; Talebi, H A; Sedigh, A K

2012-01-01

This paper presents a novel teleoperation controller for a nonlinear master-slave robotic system with constant time delay in communication channel. The proposed controller enables the teleoperation system to compensate human and environmental disturbances, while achieving master and slave position coordination in both free motion and contact situation. The current work basically extends the passivity based architecture upon the earlier work of Lee and Spong (2006) [14] to improve position tracking and consequently transparency in the face of disturbances and environmental contacts. The proposed controller employs a PID controller in each side to overcome some limitations of a PD controller and guarantee an improved performance. Moreover, by using Fourier transform and Parseval's identity in the frequency domain, we demonstrate that this new PID controller preserves the passivity of the system. Simulation and semi-experimental results show that the PID controller tracking performance is superior to that of the PD controller tracking performance in slave/environmental contacts. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

Characteristics of temporal summation of second pain sensations elicited by brief contact of glabrous skin by a preheated thermode.

PubMed

Vierck, C J; Cannon, R L; Fry, G; Maixner, W; Whitsel, B L

1997-08-01

Temporal summation of sensory intensity was investigated in normal subjects using novel methods of thermal stimulation. A Peltier thermode was heated and then applied in a series of brief (700 ms) contacts to different sites on the glabrous skin of either hand. Repetitive contacts on the thenar or hypothenar eminence, at interstimulus intervals (ISIs) of 3 s, progressively increased the perceived intensity of a thermal sensation that followed each contact at an onset latency > 2 s. Temporal summation of these delayed (late) sensations was proportional to thermode temperature over a range of 45-53 degrees C, progressing from a nonpainful level (warmth) to painful sensations that could be rated as very strong after 10 contacts. Short-latency pain sensations rarely were evoked by such stimuli and never attained levels substantially above pain threshold for the sequences and temperatures presented. Temporal summation produced by brief contacts was greater in rate and amount than increases in sensory intensity resulting from repetitive ramping to the same temperature by a thermode in constant contact with the skin. Variation of the interval between contacts revealed a dependence of sensory intensity on interstimulus interval that is similar to physiological demonstrations of windup, where increasing frequencies of spike train activity are evoked from spinal neurons by repetitive activation of unmyelinated nociceptors. However, substantial summation at repetition rates of > or = 0.33 Hz was observed for temperatures that produced only late sensations of warmth when presented at frequencies < 0.16 Hz. Measurements of subepidermal skin temperature from anesthetized monkeys revealed different time courses for storage and dissipation of heat by the skin than for temporal summation and decay of sensory intensity for the human subjects. For example, negligible heat loss occurred during a 6-s interval between two trials of 10 contacts at 0.33 Hz, but ratings of sensory magnitude decreased from very strong levels of pain to sensations of warmth during the same interval. Evidence that temporal summation of sensory intensity during series of brief contacts relies on central integration, rather than a sensitization of peripheral receptors, was obtained using two approaches. In the first, a moderate degree of temporal summation was observed during alternating stimulation of adjacent but nonoverlapping skin sites at 0.33 Hz. Second, temporal summation was significantly attenuated by prior administration of dextromethorphan, a N-methyl-D-aspartate receptor antagonist.

Direct-reading group-delay measurement

NASA Technical Reports Server (NTRS)

Trowbridge, D. L.

1978-01-01

Technique for measuring modulation signal retardation in microwave components gives direct plot of dependence of delay time on carrier frequency. Recorder sensitivity can be adjusted to give convenient scale factor for group delay. From family of such recordings, it is possible to observe changes in group delay due to temperature, mechanical stress, and other factors.

Battlefield-Acquired Immunogenicity to Metals Affects Orthopaedic Implant Outcome

DTIC Science & Technology

2015-10-01

dermat itis? Contact Dermatit is 1993;28:15-25. (13) Cramers M, Lucht U. Metal sensitivity in patients treated for tibial fractures with plates of...Zitting A, Jolanki R, Tarvainen K. Nickel release from metals, and a case of allergic contact dermatitis from stainless steel. Contact Dermatit is... Dermat itis 1994;31:249-55. (30) Gawkrodger DJ. Nickel sensitivity and the implantation of orthopaedic prostheses. Contact Dermatit is 1993;28:257 -9

Contact-Allergic Reactions to Cosmetics

PubMed Central

Goossens, An

2011-01-01

Contact-allergic reactions to cosmetics may be delayed-type reactions such as allergic and photo-allergic contact dermatitis, and more exceptionally also immediate-type reactions, that is, contact urticaria. Fragrances and preservative agents are the most important contact allergens, but reactions also occur to category-specific products such as hair dyes and other hair-care products, nail cosmetics, sunscreens, as well as to antioxidants, vehicles, emulsifiers, and, in fact, any possible cosmetic ingredient. Patch and prick testing to detect the respective culprits remains the golden standard for diagnosis, although additional tests might be useful as well. Once the specific allergens are identified, the patients should be informed of which products can be safely used in the future. PMID:21461388

Prolonged breastfeeding and delayed introduction of whole cow's milk into the diet are factors associated with egg sensitization: A matched case-control study.

PubMed

Bedolla-Barajas, M; Morales-Romero, J; Gaxiola-Arredondo, B Y; Alcalá-Padilla, G; Romero-Velarde, E

2018-05-05

Both breastfeeding and the moment at which introduction to solid food occurs have been associated with food allergy. To evaluate whether prolonged breastfeeding and the delayed introduction of whole cow's milk into an infant's diet are factors that can be associated with egg sensitization. This was a hospital-based case-control study, matched by age and sex: each study group comprised 97 atopic children. Additionally, logistic regression was used to identify the factors associated with egg protein sensitization. The most common type of allergic disease among both groups was allergic rhinitis. After adjusting for possible confounding variables, a delayed introduction to whole cow's milk decreased the odds of egg protein sensitization; OR=0.16 (95% CI: 0.07-0.36, p<0.0001). Notably, breastfeeding during the first six months of life, regardless of whether it was the only milk an infant drank, increased the risk for sensitization to chicken eggs; OR=5.54 (95% CI: 2.41-12.7, p<0.0001). Prolonged breastfeeding, regardless of whether it was the only milk an infant drank, greatly increased the risk of egg sensitization. Interestingly, a delayed introduction to whole cow's milk was associated with a reduced possibility of becoming sensitized to eggs. Further studies are required to elucidate these findings. Copyright © 2018 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Method to protect charge recombination in the back-contact dye-sensitized solar cell.

PubMed

Yoo, Beomjin; Kim, Kang-Jin; Lee, Doh-Kwon; Kim, Kyungkon; Ko, Min Jae; Kim, Yong Hyun; Kim, Won Mok; Park, Nam-Gyu

2010-09-13

We prepared a back-contact dye-sensitized solar cell and investigated effect of the sputter deposited thin TiO₂ film on the back-contact ITO electrode on photovoltaic property. The nanocrystalline TiO₂ layer with thickness of about 11 μm formed on a plain glass substrate in the back-contact structure showed higher optical transmittance than that formed on an ITO-coated glass substrate, which led to an improved photocurrent density by about 6.3%. However, photovoltage was found to decrease from 817 mV to 773 mV. The photovoltage recovered after deposition of a 35 nm-thick thin TiO₂ film on the surface of the back-contact ITO electrode. Little difference in time constant for electron transport was found for the back-contact ITO electrodes with and without the sputter deposited thin TiO₂ film. Whereas, time constant for charge recombination increased after introduction of the thin TiO₂ film, indicating that such a thin TiO₂ film protected back electron transfer, associated with the recovery of photovoltage. As the result of the improved photocurrent density without deterioration of photovoltage, the back-contact dye-sensitized solar cell exhibited 13.6% higher efficiency than the ITO-coated glass substrate-based dye-sensitized solar cell.

Identification of contact and respiratory sensitizers according to IL-4 receptor α expression and IL-2 production

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

Goutet, Michèle, E-mail: michele.goutet@inrs.fr; Pépin, Elsa; Langonné, Isabelle

2012-04-15

Identification of allergenic chemicals is an important occupational safety issue. While several methods exist to identify contact sensitizers, there is currently no validated model to predict the potential of chemicals to act as respiratory sensitizers. Previously, we reported that cytometry analysis of the local immune responses induced in mice dermally exposed to the respiratory sensitizer trimellitic anhydride (TMA 10%) and contact sensitizer dinitrochlorobenzene (DNCB 1%) could identify divergent expression of several immune parameters. The present study confirms, first, that IgE-positive B cells, MHC class II molecules, interleukin (IL)-2, IL-4 and IL-4Rα can differentiate the allergic reactions caused by high dosesmore » of strong respiratory (TMA, phthalic anhydride and toluene diisocyanate) and contact sensitizers (DNCB, dinitrofluorobenzene and oxazolone). The second part of the study was designed to test the robustness of these markers when classing the weakly immunogenic chemicals most often encountered. Six respiratory allergens, including TMA (2.5%), five contact allergens, including DNCB (0.25%), and two irritants were compared at doses of equivalent immunogenicity. The results indicated that IL-4Rα and IL-2 can be reliably used to discriminate sensitizers. Respiratory sensitizers induced markedly higher IL-4Rα levels than contact allergens, while irritants had no effect on this parameter. Inversely, contact allergens tended to induce higher percentages of IL-2{sup +}CD8{sup +} cells than respiratory allergens. In contrast, the markers MHC-II, IgE and IL-4 were not able to classify chemicals with low immunogenic potential. In conclusion, IL-4Rα and IL-2 have the potential to be used in classifying a variety of chemical allergens. -- Highlights: ► Identification of chemical allergens is an important occupational safety issue. ► There is currently no model to predict the potential of chemicals to induce asthma. ► We analyze immune responses induced in mice by a variety of chemical sensitizers. ► IL-2 and IL-4R alpha show potential to discriminate between both types of allergens. ► This method could be applied to highly and weakly immunogenic chemicals.« less

Vibration sensitivity of the scanning near-field optical microscope with a tapered optical fiber probe.

PubMed

Chang, Win-Jin; Fang, Te-Hua; Lee, Haw-Long; Yang, Yu-Ching

2005-01-01

In this paper the Rayleigh-Ritz method was used to study the scanning near-field optical microscope (SNOM) with a tapered optical fiber probe's flexural and axial sensitivity to vibration. Not only the contact stiffness but also the geometric parameters of the probe can influence the flexural and axial sensitivity to vibration. According to the analysis, the lateral and axial contact stiffness had a significant effect on the sensitivity of vibration of the SNOM's probe, each mode had a different level of sensitivity and in the first mode the tapered optical fiber probe was the most acceptive to higher levels of flexural and axial vibration. Generally, when the contact stiffness was lower, the tapered probe was more sensitive to higher levels of both axial and flexural vibration than the uniform probe. However, the situation was reversed when the contact stiffness was larger. Furthermore, the effect that the probe's length and its tapered angle had on the SNOM's probe axial and flexural vibration were significant and these two conditions should be incorporated into the design of new SNOM probes.

Food-Related Contact Dermatitis, Contact Urticaria, and Atopy Patch Test with Food.

PubMed

Walter, Alexandra; Seegräber, Marlene; Wollenberg, Andreas

2018-06-07

A wide variety of foods may cause or aggravate skin diseases such as contact dermatitis, contact urticaria, or atopic dermatitis (AD), both in occupational and private settings. The mechanism of action underlying allergic disease to food, food additives, and spices may be immunologic and non-immunologic. The classification and understanding of these reactions is a complex field, and knowledge of the possible reaction patterns and appropriate diagnostic test methods is essential. In addition, certain foods may cause worsening of atopic dermatitis lesions in children. The atopy patch test (APT) is a well-established, clinically useful tool for assessing delayed type reactions to protein allergens in patients and may be useful to detect protein allergens relevant for certain skin diseases. The APT may even detect sensitization against allergens in intrinsic atopic dermatitis patients, who show negative skin prick test and negative in vitro IgE test results against these allergens. Native foods, SPT solutions on filter paper, and purified allergens in petrolatum have been used for APT. The European Task Force on Atopic Dermatitis (ETFAD) has worked on standardizing this test in the context of AD patients, who are allergic to aeroallergens and food. This recommended, standardized technique involves test application at the upper back of children and adults; use of large, 12-mm Finn chambers; avoidance of any pre-treatment such as tape stripping or delipidation; standardized amounts of purified allergens in petrolatum; and use of the standardized ETFAD reading key. The APT may not be the best working or best standardized of all possible skin tests, but it is the best test that we currently have available in this niche.

Corneal and conjunctival sensory function: the impact on ocular surface sensitivity of change from low to high oxygen transmissibility contact lenses.

PubMed

Golebiowski, Blanka; Papas, Eric B; Stapleton, Fiona

2012-03-09

Deprivation of oxygen to the ocular surface during contact lens wear has been implicated in the alteration of sensory function. This study investigates whether increasing oxygen availability through discontinuation of contact lens wear or transfer into highly oxygen transmissible (high Dk/t) lenses leads to a change in corneal or conjunctival sensitivity. Twenty-seven long-term extended wearers of low Dk/t soft contact lenses ceased lens wear for 1 week and were refitted with high Dk/t silicone hydrogel lenses. A control group of 25 nonwearers matched for age and sex was also recruited. Central corneal and inferior conjunctival sensitivity were measured using an air-jet aesthesiometer. Threshold was determined using a staircase technique. Measurements were taken during low Dk/t lens wear; after 1 week of no wear; and after 1, 3, 6, and 12 months of high Dk/t lens wear. Measurements were carried out on one occasion on the nonwearers. Corneal sensitivity decreased 1 week after discontinuation of low Dk/t lenses and no further change in sensitivity occurred with high Dk/t lens wear. Conjunctival sensitivity did not change over the same time frame. Ocular surface sensitivity in long-term low Dk/t soft lens wearers was similar to that of nonwearers. Sensitivity was higher in females than males in the nonwearers, but not in the lens-wearing group. An interaction of sex on change in conjunctival threshold was found in the lens wearers. These findings indicate that factors other than oxygen availability alone determine sensitivity of the ocular surface. Silicone hydrogel contact lenses appear to have only a minor impact on ocular surface sensitivity in previous lens wearers.

Limits to Forecasting Precision for Outbreaks of Directly Transmitted Diseases

PubMed Central

Drake, John M

2006-01-01

Background Early warning systems for outbreaks of infectious diseases are an important application of the ecological theory of epidemics. A key variable predicted by early warning systems is the final outbreak size. However, for directly transmitted diseases, the stochastic contact process by which outbreaks develop entails fundamental limits to the precision with which the final size can be predicted. Methods and Findings I studied how the expected final outbreak size and the coefficient of variation in the final size of outbreaks scale with control effectiveness and the rate of infectious contacts in the simple stochastic epidemic. As examples, I parameterized this model with data on observed ranges for the basic reproductive ratio (R 0) of nine directly transmitted diseases. I also present results from a new model, the simple stochastic epidemic with delayed-onset intervention, in which an initially supercritical outbreak (R 0 > 1) is brought under control after a delay. Conclusion The coefficient of variation of final outbreak size in the subcritical case (R 0 < 1) will be greater than one for any outbreak in which the removal rate is less than approximately 2.41 times the rate of infectious contacts, implying that for many transmissible diseases precise forecasts of the final outbreak size will be unattainable. In the delayed-onset model, the coefficient of variation (CV) was generally large (CV > 1) and increased with the delay between the start of the epidemic and intervention, and with the average outbreak size. These results suggest that early warning systems for infectious diseases should not focus exclusively on predicting outbreak size but should consider other characteristics of outbreaks such as the timing of disease emergence. PMID:16435887

Allergic contact cheilitis from a lipstick misdiagnosed as herpes labialis: Subsequent worsening due to Zovirax contact allergy.

PubMed

Ozkaya, Esen; Topkarci, Zeynep; Ozarmağan, Güzin

2007-08-01

A 29-year-old Turkish woman with allergic contact cheilitis from a lipstick was misdiagnosed as herpes labialis and subsequently worsened with the application of Zovirax cream. Patch tests were positive to Zovirax cream, propylene glycol, the patient's favourite lipstick and propyl gallate. No reaction was seen with Zovirax ophthalmic ointment and Zovirax tablet. The propylene glycol component of the Zovirax cream and the propyl gallate component of the lipstick were regarded as the responsible contact sensitizers. The differential diagnosis was challenging due to concomitant contact sensitization with these agents.

Isolating behavioral mechanisms of intertemporal choice: nicotine effects on delay discounting and amount sensitivity.

PubMed

Locey, Matthew L; Dallery, Jesse

2009-03-01

Many drugs of abuse produce changes in impulsive choice, that is, choice for a smaller-sooner reinforcer over a larger-later reinforcer. Because the alternatives differ in both delay and amount, it is not clear whether these drug effects are due to the differences in reinforcer delay or amount. To isolate the effects of delay, we used a titrating delay procedure. In phase 1, 9 rats made discrete choices between variable delays (1 or 19 s, equal probability of each) and a delay to a single food pellet. The computer titrated the delay to a single food pellet until the rats were indifferent between the two options. This indifference delay was used as the starting value for the titrating delay for all future sessions. We next evaluated the acute effects of nicotine (subcutaneous 1.0, 0.3, 0.1, and 0.03 mg/kg) on choice. If nicotine increases delay discounting, it should have increased preference for the variable delay. Instead, nicotine had very little effect on choice. In a second phase, the titrated delay alternative produced three food pellets instead of one, which was again produced by the variable delay (1 s or 19 s) alternative. Under this procedure, nicotine increased preference for the one pellet alternative. Nicotine-induced changes in impulsive choice are therefore likely due to differences in reinforcer amount rather than differences in reinforcer delay. In addition, it may be necessary to include an amount sensitivity parameter in any mathematical model of choice when the alternatives differ in reinforcer amount.

Hipersensitivity Reactions to Corticosteroids.

PubMed

Berbegal, L; DeLeon, F J; Silvestre, J F

2016-03-01

Corticosteroids are widely used drugs in the clinical practice, especially by topic application in dermatology. These substances may act as allergens and produce immediate and delayed hypersensitivity reactions. Allergic contact dermatitis is the most frequent presentation of corticosteroid allergy and it should be studied by patch testing in specific units. The corticosteroids included in the Spanish standard battery are good markers but not ideal. Therefore, if those makers are positive, it is useful to apply a specific battery of corticosteroids and the drugs provided by patients. Immediate reactions are relatively rare but potentially severe, and it is important to confirm the sensitization profile and to guide the use of alternative corticosteroids, because they are often necessary in several diseases. In this article we review the main concepts regarding these two types of hypersensitivity reactions in corticosteroid allergy, as well as their approach in the clinical practice. Copyright © 2015 Elsevier España, S.L.U. and AEDV. All rights reserved.

Dynamic Routing for Delay-Tolerant Networking in Space Flight Operations

NASA Technical Reports Server (NTRS)

Burleigh, Scott

2008-01-01

Computational self-sufficiency - the making of communication decisions on the basis of locally available information that is already in place, rather than on the basis of information residing at other entities - is a fundamental principle of Delay-Tolerant Networking. Contact Graph Routing is an attempt to apply this principle to the problem of dynamic routing in an interplanetary DTN. Testing continues, but preliminary results are promising.

Immediate newborn care practices delay thermoregulation and breastfeeding initiation

PubMed Central

Sobel, Howard L; Silvestre, Maria Asuncion A; Mantaring, Jacinto Blas V; Oliveros, Yolanda E; Nyunt-U, Soe

2011-01-01

Aim A deadly nosocomial outbreak in a Philippine hospital drew nationwide attention to neonatal sepsis. Together with specific infection control measures, interventions that protect newborns against infection-related mortality include drying, skin-to-skin contact, delayed cord clamping, breastfeeding initiation and delayed bathing. This evaluation characterized hospital care in the first hours of life with the intent to drive policy change, strategic planning and hospital reform. Methods Trained physicians observed 481 consecutive deliveries in 51 hospitals using a standardized tool to record practices and timing of immediate newborn care procedures. Results Drying, weighing, eye care and vitamin K injections were performed in more than 90% of newborns. Only 9.6% were allowed skin-to-skin contact. Interventions were inappropriately sequenced, e.g. immediate cord clamping (median 12 sec), delayed drying (96.5%) and early bathing (90.0%). While 68.2% were put to the breast, they were separated two minutes later. Unnecessary suctioning was performed in 94.9%. Doctors trained in neonatal resuscitation were 2.5 (1.1–5.7) times more likely to unnecessarily suction vigorous newborns. Two per cent died and 5.7% developed sepsis/pneumonia. Conclusions This minute-by-minute observational assessment revealed that performance and timing of immediate newborn care interventions are below WHO standards and deprive newborns of basic protections against infection and death. PMID:21375583

Dynamic Routing for Delay-Tolerant Networking in Space Flight Operations

NASA Technical Reports Server (NTRS)

Burleigh, Scott C.

2008-01-01

Contact Graph Routing (CGR) is a dynamic routing system that computes routes through a time-varying topology composed of scheduled, bounded communication contacts in a network built on the Delay-Tolerant Networking (DTN) architecture. It is designed to support operations in a space network based on DTN, but it also could be used in terrestrial applications where operation according to a predefined schedule is preferable to opportunistic communication, as in a low-power sensor network. This paper will describe the operation of the CGR system and explain how it can enable data delivery over scheduled transmission opportunities, fully utilizing the available transmission capacity, without knowing the current state of any bundle protocol node (other than the local node itself) and without exhausting processing resources at any bundle router.

Dynamics of a particle with friction and delay

NASA Astrophysics Data System (ADS)

Monteiro Marques, Manuel D. P.; Dzonou, Raoul

2018-03-01

We are interested in the motion of a simple mechanical system having a finite number of degrees of freedom subjected to a unilateral constraint with dry friction and delay effects (with maximal duration τ > 0). At the contact point, we characterize the friction by a Coulomb law associated with a friction cone. Starting from a formulation of the problem that was given by Jean-Jacques Moreau in the form of a second-order differential inclusion in the sense of measures, we consider a sweeping process algorithm that converges towards a solution to the dynamical contact problem. The mathematical machinery as well as the general plan of the existence proof may seem much too heavy in order to treat just this simple case, but they have proved useful in more complex settings. xml:lang="fr"

Skin testing of guinea pigs and footpad testing of mice with a new antigen for detecting delayed hypersensitivity to Cryptococcus neoformans.

PubMed

Murphy, J W; Gregory, J A; Larsh, H W

1974-02-01

This study was undertaken to evaluate the potential of a cryptococcal culture filtrate antigen, cryptococcin C184, for detecting delayed hypersensitivity in Cryptococcus neoformans-injected animals. The antigen was tested on guinea pigs which had received saline or C. neoformans and on animals sensitized to Histoplasma capsulatum, Blastomyces dermatitidis, Candida albicans, or Sporothrix schenckii. A delayed-type hypersensitivity response was elicited by cryptococcin C184 in C. neoformans-injected guinea pigs, whereas no indurations or erythemas were seen at 48 h after skin testing of saline controls or heterologously sensitized guinea pigs. Besides being specific for Cryptococcus, the antigen showed a high degree of sensitivity and was reproducible. Footpad tests were conducted with the antigen on mice which had previously received either 10(5) viable C. neoformans cells or saline. Delayed hypersensitivity was indicated in the C. neoformans-injected mice by the increase in thickness of antigen-injected footpads when compared with the saline-injected footpads. In control mice, antigen- and saline-injected footpads were comparable in thickness 24 h after injection. Mice sensitized to B. dermatitidis were footpad tested with C184, and no cross-reactivity was demonstrated.

Frequency dependence of sensitivities in second-order RC active filters

NASA Astrophysics Data System (ADS)

Kunieda, T.; Hiramatsu, Y.; Fukui, A.

1980-02-01

This paper presents that gain and phase sensitivities to some element in biquadratic filters approximately constitute a circle on the complex sensitivity plane, provided that the quality factor Q of the circuit is appreciably larger than unity. Moreover, the group delay sensitivity is represented by the imaginary part of a cardioid. Using these results, bounds of maximum values of gain, phase, and group delay sensitivities are obtained. Further, it is proved that the maximum values of these sensitivities can be simultaneously minimized by minimizing the absolute value of the transfer function sensitivity at the center frequency provided that w(0)-sensitivities are constant and do not contain design parameters. Next, a statistical variability measure for the optimal-filter design is proposed. Finally, the relation between some variability measures proposed to the present time is made clear.

Three degree-of-freedom force feedback control for robotic mating of umbilical lines

NASA Technical Reports Server (NTRS)

Fullmer, R. Rees

1988-01-01

The use of robotic manipulators for the mating and demating of umbilical fuel lines to the Space Shuttle Vehicle prior to launch is investigated. Force feedback control is necessary to minimize the contact forces which develop during mating. The objective is to develop and demonstrate a working robotic force control system. Initial experimental force control tests with an ASEA IRB-90 industrial robot using the system's Adaptive Control capabilities indicated that control stability would by a primary problem. An investigation of the ASEA system showed a 0.280 second software delay between force input commands and the output of command voltages to the servo system. This computational delay was identified as the primary cause of the instability. Tests on a second path into the ASEA's control computer using the MicroVax II supervisory computer show that time delay would be comparable, offering no stability improvement. An alternative approach was developed where the digital control system of the robot was disconnected and an analog electronic force controller was used to control the robot's servosystem directly, allowing the robot to use force feedback control while in rigid contact with a moving three-degree-of-freedom target. An alternative approach was developed where the digital control system of the robot was disconnected and an analog electronic force controller was used to control the robot's servo system directly. This method allowed the robot to use force feedback control while in rigid contact with moving three degree-of-freedom target. Tests on this approach indicated adequate force feedback control even under worst case conditions. A strategy to digitally-controlled vision system was developed. This requires switching between the digital controller when using vision control and the analog controller when using force control, depending on whether or not the mating plates are in contact.

ER-mitochondria contacts control surface glycan expression and sensitivity to killer lymphocytes in glioma stem-like cells.

PubMed

Bassoy, Esen Yonca; Kasahara, Atsuko; Chiusolo, Valentina; Jacquemin, Guillaume; Boydell, Emma; Zamorano, Sebastian; Riccadonna, Cristina; Pellegatta, Serena; Hulo, Nicolas; Dutoit, Valérie; Derouazi, Madiha; Dietrich, Pierre Yves; Walker, Paul R; Martinvalet, Denis

2017-06-01

Glioblastoma is a highly heterogeneous aggressive primary brain tumor, with the glioma stem-like cells (GSC) being more sensitive to cytotoxic lymphocyte-mediated killing than glioma differentiated cells (GDC). However, the mechanism behind this higher sensitivity is unclear. Here, we found that the mitochondrial morphology of GSCs modulates the ER-mitochondria contacts that regulate the surface expression of sialylated glycans and their recognition by cytotoxic T lymphocytes and natural killer cells. GSCs displayed diminished ER-mitochondria contacts compared to GDCs. Forced ER-mitochondria contacts in GSCs increased their cell surface expression of sialylated glycans and reduced their susceptibility to cytotoxic lymphocytes. Therefore, mitochondrial morphology and dynamism dictate the ER-mitochondria contacts in order to regulate the surface expression of certain glycans and thus play a role in GSC recognition and elimination by immune effector cells. Targeting the mitochondrial morphology, dynamism, and contacts with the ER could be an innovative strategy to deplete the cancer stem cell compartment to successfully treat glioblastoma. © 2017 The Authors.

Contact sensitizing potential of pyrogallol and 5-amino-o-cresol in female BALB/c Mice

PubMed Central

Guo, T.L.; Germolec, D.R.; Zhang, Ling X.; Auttachoat, W.; Smith, M.J.; White, K.L.

2013-01-01

Hair dye components such as pyrogallol and cresol have been shown previously to promote allergic reactions such as rashes, dermal inflammation, irritation and dermatitis. The objective of this study was to determine the contact sensitization potential of pyrogallol (PYR) and 5-amino-o-cresol (AOC) when applied dermally to female BALB/c mice. Measurement of the contact hypersensitivity response was initially accomplished using the local lymph node assay. For PYR, significant increases in the proliferation of lymph node cells were observed at concentrations of 0.5% (w/v) and higher. For AOC, borderline increases, albeit significant, in auricular lymph node cell proliferation were observed at 5% and 10%. Results from the irritancy assay suggested that PYR, but not AOC, was an irritant. To further delineate whether PYR was primarily an irritant or a contact sensitizer, the mouse ear swelling test (MEST) was conducted. A significant increase in mouse ear thickness was observed at 72 hr following challenge with 0.5% PYR in mice that had been sensitized with 5% PYR. In contrast, no effects were observed in the MEST in mice sensitized and challenged with the highest achievable concentration of AOC (10%). Additional studies examining lymph node subpopulations and CD86 (B7.2) expression by B cells further support the indication that PYR was a sensitizer in BALB/c mice. The results demonstrate that PYR is both a sensitizer and an irritant in female BALB/c mice. However, the contact sensitization potential of AOC is minimal in this strain of mouse. PMID:24172597

Occupational dermatoses from exposure to epoxy resin compounds in a ski factory.

PubMed

Jolanki, R; Tarvainen, K; Tatar, T; Estlander, T; Henriks-Eckerman, M L; Mustakallio, K K; Kanerva, L

1996-06-01

Of 22 workers in a ski factory, occupational allergic contact dermatitis was found in 8. 6 were sensitive to epoxy resin compounds, i.e., epoxy resins, hardeners or diluents, 1 to cobalt in glass-fiber reinforcements, and 1 to formaldehyde in a urea-formaldehyde glue and a lacquer. 4 workers had irritant contact dermatitis from epoxy resin compounds, lacquers, sanding dust, or glass-fiber dust. 3 had contact allergy from a new sensitizer, diethyleneglycol diglycidyl ether, in a reactive diluent. Immediate transfer of workers sensitized to epoxy resin from epoxy exposure prevents aggravation of their dermatitis and broadening of the sensitization to epoxy hardeners, diluents and other compounds.

[Allergy to car seat].

PubMed

Wurpts, G; Merk, H F

2010-11-01

This is a case report of a female patient showing a delayed allergic reaction to epoxy resin. The allergic contact dermatitis occurred after sitting in her new car equipped with artificial leather seats.

Novel approach for classifying chemicals according to skin sensitizing potency by non-radioisotopic modification of the local lymph node assay.

PubMed

Takeyoshi, Masahiro; Iida, Kenji; Shiraishi, Keiji; Hoshuyama, Satsuki

2005-01-01

The murine local lymph node assay (LLNA) is currently recognized as a stand-alone sensitization test for determining the sensitizing potential of chemicals, and it has the advantage of yielding a quantitative endpoint that can be used to predict the sensitization potency of chemicals. The EC3 has been proposed as a parameter for classifying chemicals according to the sensitization potency. We previously developed a non-radioisotopic endpoint for the LLNA based on 5-bromo-2'-deoxyuridine (BrdU) incorporation (non-RI LLNA), and we are proposing a new procedure to predict the sensitization potency of chemicals based on comparisons with known human contact allergens. Nine chemicals (i.e. diphencyclopropenone, p-phenylenediamine, glutaraldehyde, cinnamicaldehyde, citral, eugenol, isopropyl myristate, propyleneglycol and hexane) categorized as human contact allergen classes 1-5 were tested by the non-RI LLNA with the following reference allergens: 2,4-dinitrochlorobenzene (DNCB) as a class 1 human contact allergen, isoeugenol as a class 2 human contact allergen and alpha-hexylcinnamic aldehyde (HCA) as a class 3 human contact allergen. Consequently, nine test chemicals were almost assigned to their correct allergen class. The results suggested that the new procedure for non-RI LLNA can provide correct sensitization potency data. Sensitization potency data are useful for evaluating the sensitization risk to humans of exposure to new chemical products. Accordingly, this approach would be an effective modification of LLNA with regard to its experimental design. Moreover, this procedure can be applied also to the standard LLNA with radioisotopes and to other modifications of the LLNA. Copyright 2005 John Wiley & Sons, Ltd.

Fingertip contact influences human postural control

NASA Technical Reports Server (NTRS)

Jeka, J. J.; Lackner, J. R.

1994-01-01

Touch and pressure stimulation of the body surface can strongly influence apparent body orientation, as well as the maintenance of upright posture during quiet stance. In the present study, we investigated the relationship between postural sway and contact forces at the fingertip while subjects touched a rigid metal bar. Subjects were tested in the tandem Romberg stance with eyes open or closed under three conditions of fingertip contact: no contact, touch contact (< 0.98 N of force), and force contact (as much force as desired). Touch contact was as effective as force contact or sight of the surroundings in reducing postural sway when compared to the no contact, eyes closed condition. Body sway and fingertip forces were essentially in phase with force contact, suggesting that fingertip contact forces are physically counteracting body sway. Time delays between body sway and fingertip forces were much larger with light touch contact, suggesting that the fingertip is providing information that allows anticipatory innervation of musculature to reduce body sway. The results are related to observations on precision grip as well as the somatosensory, proprioceptive, and motor mechanisms involved in the reduction of body sway.

Experimental development of low-frequency shear modulus and attenuation measurements in mated rock fractures: Shear mechanics due to asperity contact area changes with normal stress

DOE PAGES

Saltiel, Seth; Selvadurai, Paul A.; Bonner, Brian P.; ...

2017-02-16

Reservoir core measurements can help guide seismic monitoring of fluid-induced pressure variations in tight fractured reservoirs including those targeted for supercritical CO 2 injection. We present the first seismic-frequency ‘room-dry’ measurements of fracture specific shear stiffness, using artificially fractured standard granite samples with different degrees of mating, a well-mated tensile fracture from a dolomite reservoir core, as well as simple roughened polymethyl methacrylate (PMMA) surfaces. We have adapted a low-frequency (0.01 to 100 Hz) shear modulus and attenuation apparatus to explore the seismic signature of fractures and understand the mechanics of asperity contacts under a range of normal stress conditions.more » Our instrument is unique in its ability to measure at low normal stresses (0.5 – 20 MPa), simulating 'open' fractures in shallow or high fluid pressure reservoirs. The accuracy of our instrument is demonstrated by calibration and comparison to ultrasonic measurements and low-frequency direct shear measurements of intact samples from the literature. Pressure sensitive film was used to measure real contact area of the fracture surfaces. The fractured shear modulus for the majority of the samples shows an exponential dependence on real contact area. A simple numerical model, with one bonded circular asperity, predicts this behavior and matches the data for the simple PMMA surfaces. The rock surfaces reach their intact moduli at lower contact area than the model predicts, likely due to more complex geometry. Lastly, we apply our results to a Linear-Slip Interface Model to estimate reflection coefficients and calculate shear wave time delays due to the lower wave velocities through the fractured zone. We find that cross-well surveys could detect even well-mated hard rock fractures assuming the availability of high repeatability acquisition systems.« less

Experimental development of low-frequency shear modulus and attenuation measurements in mated rock fractures: Shear mechanics due to asperity contact area changes with normal stress

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

Saltiel, Seth; Selvadurai, Paul A.; Bonner, Brian P.

Reservoir core measurements can help guide seismic monitoring of fluid-induced pressure variations in tight fractured reservoirs including those targeted for supercritical CO 2 injection. We present the first seismic-frequency ‘room-dry’ measurements of fracture specific shear stiffness, using artificially fractured standard granite samples with different degrees of mating, a well-mated tensile fracture from a dolomite reservoir core, as well as simple roughened polymethyl methacrylate (PMMA) surfaces. We have adapted a low-frequency (0.01 to 100 Hz) shear modulus and attenuation apparatus to explore the seismic signature of fractures and understand the mechanics of asperity contacts under a range of normal stress conditions.more » Our instrument is unique in its ability to measure at low normal stresses (0.5 – 20 MPa), simulating 'open' fractures in shallow or high fluid pressure reservoirs. The accuracy of our instrument is demonstrated by calibration and comparison to ultrasonic measurements and low-frequency direct shear measurements of intact samples from the literature. Pressure sensitive film was used to measure real contact area of the fracture surfaces. The fractured shear modulus for the majority of the samples shows an exponential dependence on real contact area. A simple numerical model, with one bonded circular asperity, predicts this behavior and matches the data for the simple PMMA surfaces. The rock surfaces reach their intact moduli at lower contact area than the model predicts, likely due to more complex geometry. Lastly, we apply our results to a Linear-Slip Interface Model to estimate reflection coefficients and calculate shear wave time delays due to the lower wave velocities through the fractured zone. We find that cross-well surveys could detect even well-mated hard rock fractures assuming the availability of high repeatability acquisition systems.« less

Estimating the extent of household contact misclassification with index cases of disease in longitudinal studies using a stochastic simulation model.

PubMed

Chirwa, Tobias; Floyd, Sian; Fine, Paul

2013-01-24

Household contact with an index case of an infectious disease is a known risk factor for infection transmission. However, such contact may be underestimated due to the dynamic nature of households, particularly in longitudinal studies. Such studies generally begin with contact defined at a single point in time ('snap-shot'), leading to contact misclassification for some individuals who actually experienced contact before and after the snapshot. To quantify contact misclassification with index cases of disease in households. Historical data of 112,026 individuals from 17,889 households from an epidemiological study on leprosy in northern Malawi were used. Individuals were interviewed in the early 1980s and followed up over 5 years. It was possible to trace whether individuals died, changed household within the area, or moved out of the area between the two surveys.Using a 10% sample of households as the starting population and parameters for demographic and household changes over 5 years, the extent of contact misclassification was estimated through a simulation model of household dynamics, which traced contact with index cases in households over time. The model thereafter compared initial contact status and 'true' contact status generated from simulations. The starting population had 11,401 individuals, 52% female, and 224 (2%) leprosy index cases. Eleven percent of the households had at least one index case resident and 10% (1, 177) of non-case individuals were initial contacts. Sensitivity of initial contact status ranged from 0.52 to 0.74 and varied by age and sex. Sensitivity was low in those aged 20-29 and under 5 years but high in 5- to 14-year-olds. By gender, there were no differences among those aged under 5; females had lower sensitivity among those aged under 20 and higher for those above 30, respectively. Sensitivity was also low in simulations of long incubation periods. This work demonstrates the implications of changes in households on household contact-associated disease spread, particularly for long durations of follow-up and infections with long incubation periods where earlier unobserved contact is critical.

The rising tide of Acanthamoeba keratitis in Auckland, New Zealand: a 7-year review of presentation, diagnosis and outcomes (2009-2016).

PubMed

McKelvie, James; Alshiakhi, Moaz; Ziaei, Mohammed; Patel, Dipika V; McGhee, Charles Nj

2018-02-07

Acanthamoeba is an increasingly prevalent cause of vision-threatening microbial keratitis. To assess the incidence, clinical presentation, diagnosis and outcomes of patients with Acanthamoeba keratitis (AK) in Auckland, New Zealand over a 7-year period. Retrospective observational consecutive case series. Fifty-eight eyes of 52 patients diagnosed with AK. All cases of AK were identified using a cross-referenced search of clinical, laboratory and pharmacy records from March 2009 to May 2016. Demographic and clinical data were collected including age, gender, risk factors, clinical manifestations, initial diagnosis, diagnostic investigations, treatment, presenting and final visual acuity and surgical interventions. Contact lens (CL) use was noted in 96% of unilateral and 100% of bilateral cases. The mean duration of symptoms at presentation was 21 days and the mean duration from presentation to definitive diagnosis was 14 days. Initial diagnosis was recorded as CL-related keratitis in 70.6%, viral keratitis in 15.5% and AK in 12.0%. The diagnosis was confirmed with In vivo confocal microscopy (IVCM) in 67.2%, corneal scrape in 22.4%, corneal biopsy in 1.7% and clinically in 8.6%. IVCM sensitivity was 83.0%. Surgical intervention was required in four patients, all with delayed diagnosis (range 63-125 days). The incidence of AK has more than doubled when compared with the preceding 7-year period. AK is a rare vision-threatening protozoal infection with rapidly-increasing incidence in New Zealand, predominantly affecting CL users. Diagnosis is often challenging and when delayed is associated with worse outcomes. IVCM offers rapid diagnosis with high sensitivity. © 2018 Royal Australian and New Zealand College of Ophthalmologists.

Satellite laser ranging as a tool for the recovery of tropospheric gradients

NASA Astrophysics Data System (ADS)

Drożdżewski, M.; Sośnica, K.

2018-11-01

Space geodetic techniques, such as Global Navigation Satellite Systems (GNSS) and Very Long Baseline Interferometry (VLBI) have been extensively used for the recovery of the tropospheric parameters. Both techniques employ microwave observations, for which the troposphere is a non-dispersive medium and which are very sensitive to the water vapor content. Satellite laser ranging (SLR) is the only space geodetic technique used for the definition of the terrestrial reference frames which employs optical - laser observations. The SLR sensitivity to the hydrostatic part of the troposphere delay is similar to that of microwave observations, whereas the sensitivity of laser observations to non-hydrostatic part of the delay is about two orders of magnitude smaller than in the case of microwave observations. Troposphere is a dispersive medium for optical wavelengths, which means that the SLR tropospheric delay depends on the laser wavelength. This paper presents the sensitivity and capability of the SLR observations for the recovery of azimuthal asymmetry over the SLR stations, which can be described as horizontal gradients of the troposphere delay. For the first time, the horizontal gradients are estimated, together with other parameters typically estimated from the SLR observations to spherical LAGEOS satellites, i.e., station coordinates, earth rotation parameters, and satellite orbits. Most of the SLR stations are co-located with GNSS receivers, thus, a cross-correlation between both techniques is possible. We compare our SLR horizontal gradients to GNSS results and to the horizontal gradients derived from the numerical weather models (NWM). Due to a small number of the SLR observations, SLR is not capable of reconstructing short-period phenomena occurring in the atmosphere. However, the long-term analysis allows for the recovery of the atmosphere asymmetry using SLR. As a result, the mean offsets of the SLR-derived horizontal gradients agree to the level of 47%, 74%, 54% with GNSS, hydrostatic delay, and total delay from NWM, respectively. SLR can be thus employed as a tool for the recovery of the atmospheric parameters with a major sensitivity to the hydrostatic part of the delay.

Hair dye dermatitis and p-phenylenediamine contact sensitivity: A preliminary report

PubMed Central

Gupta, Mrinal; Mahajan, Vikram K.; Mehta, Karaninder S.; Chauhan, Pushpinder S.

2015-01-01

Background: The contact allergic reactions from p-phenylenediamine (PPD) in hair dyes vary from mild contact dermatitis to severe life- threatening events (angioedema, bronchospasm, asthma, renal impairment). Objectives: To study the clinical patterns and PPD contact sensitivity in patients with hair-dye dermatitis. Materials and Methods: Eighty (M:F 47:33) consecutive patients aged between 18 and 74 years suspected to have contact allergy from hair dye were studied by patch testing with Indian Standard Series including p-phenylenediamine (PPD, 1.0% pet). Results: 54 Fifty-four (M:F 21:33) patients showed positive patch tests from PPD. Eight of these patients also showed positive patch test reaction from fragrance mix, thiuram mix, paraben mix, or colophony. Fifty-seven (71%) patients affected were aged older than 40 years. The duration of dermatitis varied from < 1 month to > 1 year with exacerbation following hair coloring. Forty-nine patients had dermatitis of scalp and/or scalp margins and 23 patients had face and neck dermatitis. Periorbital dermatitis, chronic actinic dermatitis, and erythema multiforme-like lesions were seen in 4, 2, and 1 patients, respectively. Conclusions: Hair dyes and PPD constitute a significant cause of contact dermatitis. There is an urgent need for creating consumer awareness regarding hair-dyes contact sensitivity and the significance of performing sensitivity testing prior to actual use. PMID:26225326

Cystoscopy and Ureteroscopy

MedlinePlus

... urinary urgency—the inability to delay urination urinary retention —the inability to empty the bladder completely urinary ... Coordinating Committees Strategic Plans & Reports Research Areas FAQs Jobs at NIDDK Visit Us Contact Us News News ...

Nucleus accumbens core lesions induce sub-optimal choice and reduce sensitivity to magnitude and delay in impulsive choice tasks

PubMed Central

Steele, Catherine C.; Peterson, Jennifer R.; Marshall, Andrew T.; Stuebing, Sarah L.; Kirkpatrick, Kimberly

2017-01-01

The nucleus accumbens core (NAc) has long been recognized as an important contributor to the computation of reward value that is critical for impulsive choice behavior. Impulsive choice refers to choosing a smaller-sooner (SS) over a larger-later (LL) reward when the LL is more optimal in terms of the rate of reward delivery. Two experiments examined the role of the NAc in impulsive choice and its component processes of delay and magnitude processing. Experiment 1 delivered an impulsive choice task with manipulations of LL reward magnitude, followed by a reward magnitude discrimination task. Experiment 2 tested impulsive choice under manipulations of LL delay, followed by temporal bisection and progressive interval tasks. NAc lesions, in comparison to sham control lesions, produced suboptimal preferences that resulted in lower reward earning rates, and led to reduced sensitivity to magnitude and delay within the impulsive choice task. The secondary tasks revealed intact reward magnitude and delay discrimination abilities, but the lesion rats persisted in responding more as the progressive interval increased during the session. The results suggest that the NAc is most critical for demonstrating good sensitivity to magnitude and delay, and adjusting behavior accordingly. Ultimately, the NAc lesions induced suboptimal choice behavior rather than simply promoting impulsive choice, suggesting that an intact NAc is necessary for optimal decision making. PMID:29146281

Correlation between tuberculin skin test and IGRAs with risk factors for the spread of infection in close contacts with sputum smear positive in pulmonary tuberculosis.

PubMed

de Souza-Galvão, Maria Luiza; Latorre, Irene; Altet-Gómez, Neus; Jiménez-Fuentes, María Ángeles; Milà, Celia; Solsona, Jordi; Seminario, Maria Asunción; Cantos, Adela; Ruiz-Manzano, Juan; Domínguez, José

2014-05-13

The aim of the study was to assess the correlation between the tuberculin skin test (TST) and in vitro interferon-gamma released assays (IGRAs) with risk factors for the spread of infection in smear positive pulmonary tuberculosis (TB) contacts. We recruited prospective contacts with smear positive pulmonary TB cases. We looked at human immunodeficiency virus (HIV) infection and other conditions of immunosuppression, presence of BCG vaccination and the degree of exposure to the index case. Patients underwent the TST, chest radiography, sputum analysis when necessary, and IGRA assays (QFN-G-IT and T-SPOT.TB). Presence of cough, diagnostic delay (days between first symptoms and TB diagnostic), contact conditions: room size (square meters) and index of overcrowding (square meters per person) were investigated in the index case. 156 contacts (119 adults, 37 children) of 66 TB patients were enrolled, 2.4 (1-14) contacts per TB case. The positivity of the TST did not correlate with the risk factors studied: presence of cough (p = 0.929); delayed diagnosis (p = 0.244); room size (p = 0.462); overcrowding (p = 0.800). Both QFN-G-IT and T-SPOT.TB, showed significant association with cough (p = 0.001, and p = 0.007) and room size (p = 0.020, and p = 0.023), respectively. Both IGRA associated better than TST with certain host-related risk factors involved in the transmission of disease, such as the presence of cough.

Correlation between tuberculin skin test and IGRAs with risk factors for the spread of infection in close contacts with sputum smear positive in pulmonary tuberculosis

PubMed Central

2014-01-01

Background The aim of the study was to assess the correlation between the tuberculin skin test (TST) and in vitro interferon-gamma released assays (IGRAs) with risk factors for the spread of infection in smear positive pulmonary tuberculosis (TB) contacts. Methods We recruited prospective contacts with smear positive pulmonary TB cases. We looked at human immunodeficiency virus (HIV) infection and other conditions of immunosuppression, presence of BCG vaccination and the degree of exposure to the index case. Patients underwent the TST, chest radiography, sputum analysis when necessary, and IGRA assays (QFN-G-IT and T-SPOT.TB). Presence of cough, diagnostic delay (days between first symptoms and TB diagnostic), contact conditions: room size (square meters) and index of overcrowding (square meters per person) were investigated in the index case. Results 156 contacts (119 adults, 37 children) of 66 TB patients were enrolled, 2.4 (1-14) contacts per TB case. The positivity of the TST did not correlate with the risk factors studied: presence of cough (p = 0.929); delayed diagnosis (p = 0.244); room size (p = 0.462); overcrowding (p = 0.800). Both QFN-G-IT and T-SPOT.TB, showed significant association with cough (p = 0.001, and p = 0.007) and room size (p = 0.020, and p = 0.023), respectively. Conclusions Both IGRA associated better than TST with certain host-related risk factors involved in the transmission of disease, such as the presence of cough. PMID:24885850

Isolating Behavioral Mechanisms of Inter-Temporal Choice: Nicotine Effects on Delay Discounting and Amount Sensitivity

ERIC Educational Resources Information Center

Locey, Matthew L.; Dallery, Jesse

2009-01-01

Many drugs of abuse produce changes in impulsive choice, that is, choice for a smaller-sooner reinforcer over a larger-later reinforcer. Because the alternatives differ in both delay and amount, it is not clear whether these drug effects are due to the differences in reinforcer delay or amount. To isolate the effects of delay, we used a titrating…

Analytical Modeling Tool for Design of Hydrocarbon Sensitive Optical Fibers

PubMed Central

Vahdati, Nader; Lawand, Lydia

2017-01-01

Pipelines are the main transportation means for oil and gas products across large distances. Due to the severe conditions they operate in, they are regularly inspected using conventional Pipeline Inspection Gages (PIGs) for corrosion damage. The motivation for researching a real-time distributed monitoring solution arose to mitigate costs and provide a proactive indication of potential failures. Fiber optic sensors with polymer claddings provide a means of detecting contact with hydrocarbons. By coating the fibers with a layer of metal similar in composition to that of the parent pipeline, corrosion of this coating may be detected when the polymer cladding underneath is exposed to the surrounding hydrocarbons contained within the pipeline. A Refractive Index (RI) change occurs in the polymer cladding causing a loss in intensity of a traveling light pulse due to a reduction in the fiber’s modal capacity. Intensity losses may be detected using Optical Time Domain Reflectometry (OTDR) while pinpointing the spatial location of the contact via time delay calculations of the back-scattered pulses. This work presents a theoretical model for the above sensing solution to provide a design tool for the fiber optic cable in the context of hydrocarbon sensing following corrosion of an external metal coating. Results are verified against the experimental data published in the literature. PMID:28956847

Analytical Modeling Tool for Design of Hydrocarbon Sensitive Optical Fibers.

PubMed

Al Handawi, Khalil; Vahdati, Nader; Shiryayev, Oleg; Lawand, Lydia

2017-09-28

Pipelines are the main transportation means for oil and gas products across large distances. Due to the severe conditions they operate in, they are regularly inspected using conventional Pipeline Inspection Gages (PIGs) for corrosion damage. The motivation for researching a real-time distributed monitoring solution arose to mitigate costs and provide a proactive indication of potential failures. Fiber optic sensors with polymer claddings provide a means of detecting contact with hydrocarbons. By coating the fibers with a layer of metal similar in composition to that of the parent pipeline, corrosion of this coating may be detected when the polymer cladding underneath is exposed to the surrounding hydrocarbons contained within the pipeline. A Refractive Index (RI) change occurs in the polymer cladding causing a loss in intensity of a traveling light pulse due to a reduction in the fiber's modal capacity. Intensity losses may be detected using Optical Time Domain Reflectometry (OTDR) while pinpointing the spatial location of the contact via time delay calculations of the back-scattered pulses. This work presents a theoretical model for the above sensing solution to provide a design tool for the fiber optic cable in the context of hydrocarbon sensing following corrosion of an external metal coating. Results are verified against the experimental data published in the literature.

An in vitro method for detecting chemical sensitization using human reconstructed skin models and its applicability to cosmetic, pharmaceutical, and medical device safety testing.

PubMed

McKim, James M; Keller, Donald J; Gorski, Joel R

2012-12-01

Chemical sensitization is a serious condition caused by small reactive molecules and is characterized by a delayed type hypersensitivity known as allergic contact dermatitis (ACD). Contact with these molecules via dermal exposure represent a significant concern for chemical manufacturers. Recent legislation in the EU has created the need to develop non-animal alternative methods for many routine safety studies including sensitization. Although most of the alternative research has focused on pure chemicals that possess reasonable solubility properties, it is important for any successful in vitro method to have the ability to test compounds with low aqueous solubility. This is especially true for the medical device industry where device extracts must be prepared in both polar and non-polar vehicles in order to evaluate chemical sensitization. The aim of this research was to demonstrate the functionality and applicability of the human reconstituted skin models (MatTek Epiderm(®) and SkinEthic RHE) as a test system for the evaluation of chemical sensitization and its potential use for medical device testing. In addition, the development of the human 3D skin model should allow the in vitro sensitization assay to be used for finished product testing in the personal care, cosmetics, and pharmaceutical industries. This approach combines solubility, chemical reactivity, cytotoxicity, and activation of the Nrf2/ARE expression pathway to identify and categorize chemical sensitizers. Known chemical sensitizers representing extreme/strong-, moderate-, weak-, and non-sensitizing potency categories were first evaluated in the skin models at six exposure concentrations ranging from 0.1 to 2500 µM for 24 h. The expression of eight Nrf2/ARE, one AhR/XRE and two Nrf1/MRE controlled gene were measured by qRT-PCR. The fold-induction at each exposure concentration was combined with reactivity and cytotoxicity data to determine the sensitization potential. The results demonstrated that both the MatTek and SkinEthic models performed in a manner consistent with data previously reported with the human keratinocyte (HaCaT) cell line. The system was tested further by evaluating chemicals known to be associated with the manufacture of medical devices. In all cases, the human skin models performed as well or better than the HaCaT cell model previously evaluated. In addition, this study identifies a clear unifying trigger that controls both the Nrf2/ARE pathway and essential biochemical events required for the development of ACD. Finally, this study has demonstrated that by utilizing human reconstructed skin models, it is possible to evaluate non-polar extracts from medical devices and low solubility finished products.

Contact sensitization in patients with suspected cosmetic intolerance: results of the IVDK 2006-2011.

PubMed

Dinkloh, A; Worm, M; Geier, J; Schnuch, A; Wollenberg, A

2015-06-01

Ingredients of leave-on cosmetics and body care products may sensitize. However, not every case of cosmetic intolerance is due to contact sensitization. To describe the frequency of contact sensitization due to cosmetics in a large clinic population, and a possible particular allergen pattern. Retrospective analysis of data from the Information Network of Departments of Dermatology, 2006-2011. Of 69 487 patients tested, 'cosmetics, creams, sunscreens' was the only suspected allergen source category in 10 124 patients (14.6%). A final diagnosis 'allergic contact dermatitis' was stated in 2658 of these patients (26.3%).Compared to a control group, there were significantly more reactions to fragrance mixes I and II, balsam of Peru, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and lanolin alcohols. No special pattern of fragrance sensitization could be identified. Among the preservatives, MI was by far the leading allergen, while sensitization to other widely used compounds like parabens or phenoxyethanol was rare. True allergic reactions to cosmetic ingredients are rarer than generally assumed. Limitation of exposure to MI in leave-on cosmetics and body care products is urgently needed. © 2014 European Academy of Dermatology and Venereology.

Cosmetic Contact Sensitivity in Patients with Melasma: Results of a Pilot Study

PubMed Central

Prabha, Neel; Mahajan, Vikram K.; Mehta, Karaninder S.; Chauhan, Pushpinder S.

2014-01-01

Background. Some of the patients with melasma perhaps have pigmented cosmetic dermatitis. However, cosmetic contact sensitivity in melasma remains poorly studied particularly in the Indian context. Objectives. To study cosmetic contact sensitivity in patients with melasma. Materials and Methods. 67 (F : M = 55 : 12) consecutive patients with melasma between 19 and 49 years of age were patch tested sequentially during January–December, 2012, with Indian Cosmetic and Fragrance Series, Indian Sunscreen Series, p-phenylenediamine, and patient's own cosmetic products. Results. 52 (78%) patients were in the age group of 20–40 years. The duration of melasma varied from 1 month to 20 years. Centrofacial, malar, and mandibular patterns were observed in 48 (72%), 18 (27%), and 1 (1%) patients, respectively. Indian Cosmetics and Fragrance Series elicited positive reactions in 29 (43.3%) patients. Cetrimide was the most common contact sensitizers eliciting positivity in 15 (52%) patients, followed by gallate mix in 9 (31%) patients and thiomersal in 7 (24%) patients. Only 2 of the 42 patients showed positive reaction from their own cosmetics while the other 5 patients had irritant reaction. Indian Sunscreen Series did not elicit any positive reaction. Conclusion. Cosmetics contact sensitivity appears as an important cause of melasma not associated with pregnancy, lactation, or hormone therapy. PMID:25132846

Point-contact sensors: New prospects for a nanoscale-sensitive technique

NASA Astrophysics Data System (ADS)

Kamarchuk, G. V.; Pospelov, A. P.; Yeremenko, A. V.; Faulques, E. C.; Yanson, I. K.

2006-11-01

Point contacts have been discovered to present excellent and unprecedented characteristics when used as gas sensors. A novel concept has been tested successfully and opens the way to useful applications. Copper point contacts were investigated in gas media such as NOx, HCl, H2S and human breath. They reveal high sensitivity to these gases: the measured signal increases by 2-3 orders of magnitude upon gas exposure. Sensor parameters are fully restored when gas action ceases. Stable reproducibility of experimental results was observed after several exposure cycles onto the investigated point contacts.

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.

Ethanol induces impulsive-like responding in a delay-of-reward operant choice procedure: impulsivity predicts autoshaping.

PubMed

Tomie, A; Aguado, A S; Pohorecky, L A; Benjamin, D

1998-10-01

Autoshaping conditioned responses (CRs) are reflexive and targeted motor responses expressed as a result of experience with reward. To evaluate the hypothesis that autoshaping may be a form of impulsive responding, within-subjects correlations between performance on autoshaping and impulsivity tasks were assessed in 15 Long-Evans hooded rats. Autoshaping procedures [insertion of retractable lever conditioned stimulus (CS) followed by the response-independent delivery of food (US)] were followed by testing for impulsive-like responding in a two-choice lever-press operant delay-of-reward procedure (immediate small food reward versus delayed large food reward). Delay-of-reward functions revealed two distinct subject populations. Subjects in the Sensitive group (n=7) were more impulsive-like, increasing immediate reward choices at longer delays for large reward, while those in the Insensitive group (n=8) responded predominantly on only one lever. During the prior autoshaping phase, the Sensitive group had performed more autoshaping CRs, and correlations revealed that impulsive subjects acquired the autoshaping CR in fewer trials. In the Sensitive group, acute injections of ethanol (0, 0.25, 0.50, 1.00, 1.50 g/kg) given immediately before delay-of-reward sessions yielded an inverted U-shaped dose-response curve with increased impulsivity induced by the 0.25, 0.50, and 1.00 g/kg doses of ethanol, while choice strategy of the Insensitive group was not influenced by ethanol dose. Ethanol induced impulsive-like responding only in rats that were flexible in their response strategy (Sensitive group), and this group also performed more autoshaping CRs. Data support the hypothesis that autoshaping and impulsivity are linked.

Long-term behavioral sensitization to apomorphine is independent of conditioning and increases conditioned pecking, but not preference, in pigeons.

PubMed

Anselme, Patrick; Edeş, Neslihan; Tabrik, Sepideh; Güntürkün, Onur

2018-01-15

When rodents are given a free choice between a variable option and a constant option, they may prefer variability. This preference is even sometimes increased following repeated administration of a dopamine agonist. The present study was the first to examine preference for variability under the systemic administration of a dopamine agonist, apomorphine (Apo), in birds. Experiment 1 tested the drug-free preference and the propensity to choose of pigeons for a constant over a variable delay. It appeared that they preferred and decided more quickly to peck at the optimal delay option. Experiment 2 assessed the effects of a repeated injection of Apo on delay preference, in comparison with previous control tests within the same individuals. Apo treatment might have decreased the number of pecks at the constant option across the different experimental phases, but failed to induce a preference for the variable option. In Experiment 3, two groups of pigeons (Apo-sensitized and saline) were used in order to avoid inhomogeneity in treatments. They had to choose between a 50% probability option and a 5-s delay option. Conditioned pecking and the propensity to choose were higher in the Apo-sensitized pigeons, but, in each group, the pigeons showed indifference between the two options. This experiment also showed that long-term behavioral sensitization to Apo can occur independently of a conditioning process. These results suggest that Apo sensitization can enhance the attractiveness of conditioned cues, while having no effect on the development of a preference for variable-delay and probabilistic schedules of reinforcement. Copyright © 2017 Elsevier B.V. All rights reserved.

Bayley-III Cognitive and Language Scales in Preterm Children.

PubMed

Spencer-Smith, Megan M; Spittle, Alicia J; Lee, Katherine J; Doyle, Lex W; Anderson, Peter J

2015-05-01

This study aimed to assess the sensitivity and specificity of the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III), Cognitive and Language scales at 24 months for predicting cognitive impairments in preterm children at 4 years. Children born <30 weeks' gestation completed the Bayley-III at 24 months and the Differential Ability Scale, Second Edition (DAS-II), at 4 years to assess cognitive functioning. Test norms and local term-born reference data were used to classify delay on the Bayley-III Cognitive and Language scales. Impairment on the DAS-II Global Conceptual Ability, Verbal, and Nonverbal Reasoning indices was classified relative to test norms. Scores < -1 SD relative to the mean were classified as mild/moderate delay or impairment, and scores < -2 SDs were classified as moderate delay or impairment. A total of 105 children completed the Bayley-III and DAS-II. The sensitivity of mild/moderate cognitive delay on the Bayley-III for predicting impairment on DAS-II indices ranged from 29.4% to 38.5% and specificity ranged from 92.3% to 95.5%. The sensitivity of mild/moderate language delay on the Bayley-III for predicting impairment on DAS-II indices ranged from 40% to 46.7% and specificity ranged from 81.1% to 85.7%. The use of local reference data at 24 months to classify delay increased sensitivity but reduced specificity. Receiver operating curve analysis identified optimum cut-point scores for the Bayley-III that were more consistent with using local reference data than Bayley-III normative data. In our cohort of very preterm children, delay on the Bayley-III Cognitive and Language scales was not strongly predictive of future impairments. More children destined for later cognitive impairment were identified by using cut-points based on local reference data than Bayley-III norms. Copyright © 2015 by the American Academy of Pediatrics.

Effects of intra-accumbal administration of dopamine and ionotropic glutamate receptor drugs on delay discounting performance in rats.

PubMed

Yates, Justin R; Bardo, Michael T

2017-10-01

Nucleus accumbens core (NAcc) has been implicated in impulsive choice, as measured in delay discounting. The role of dopamine (DA) in impulsive choice has received considerable attention, whereas glutamate (Glu) has recently been shown to be an important mediator of discounting. However, research has not examined how DA or Glu receptors in NAcc mediate different aspects of delay discounting performance, that is, (a) sensitivity to reinforcer magnitude and (b) sensitivity to delayed reinforcement. Adult male Sprague-Dawley rats were first trained in a delay discounting task, in which the delay to a large magnitude food reinforcer increased across blocks of trials. Following behavioral training, rats received bilateral implantation of guide cannulas into NAcc. Half of the rats (n = 12) received infusions of the DA-selective ligands SKF 38393 (D1-like agonist: 0.03 or 0.1 μg), SCH 23390 (D1-like antagonist: 0.3 or 1.0 μg), quinpirole (D2-like agonist: 0.3 or 1.0 μg), and eticlopride (D2-like antagonist: 0.3 or 1.0 μg). The other half received infusions of the ionotropic Glu ligands MK-801 (NMDA uncompetitive antagonist: 0.3 or 1.0 μg), AP-5 (NMDA competitive antagonist: 0.3 or 1.0 μg), ifenprodil (noncompetitive antagonist at NR2B-containing NMDA receptors: 0.3 or 1.0 μg), and CNQX (AMPA competitive antagonist: 0.2 or 0.5 μg). Results showed that SCH 23390 (0.3 μg) decreased sensitivity to reinforcer magnitude without altering impulsive choice, whereas ifenprodil (1.0 μg) decreased sensitivity to delayed reinforcement (i.e., impulsive choice). The current results show that DA and NMDA receptors in NAcc mediate distinct aspects of discounting performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

CNS neuroplasticity and salt-sensitive hypertension induced by prior treatment with subpressor doses of ANG II or aldosterone.

PubMed

Clayton, Sarah C; Zhang, Zhongming; Beltz, Terry; Xue, Baojian; Johnson, Alan Kim

2014-06-15

Although sensitivity to high dietary NaCl is regarded to be a risk factor for cardiovascular disease, the causes of salt-sensitive hypertension remain elusive. Previously, we have shown that rats pretreated with subpressor doses of either ANG II or aldosterone (Aldo) show sensitized hypertensive responses to a mild pressor dose of ANG II when tested after an intervening delay. The current studies investigated whether such treatments will induce salt sensitivity. In studies employing an induction-delay-expression experimental design, male rats were instrumented for chronic mean arterial pressure (MAP) recording. In separate experiments, ANG II, Aldo, or vehicle was delivered either subcutaneously or intracerebroventricularly during the induction. There were no sustained differences in BP during the delay prior to being given 2% saline. While consuming 2% saline during the expression, both ANG II- and Aldo-pretreated rats showed significantly greater hypertension. When hexamethonium was used to assess autonomic control of MAP, no differences in the decrease of MAP in response to ganglionic blockade were detected during the induction. However, during the expression, the fall was greater in sensitized rats. In separate experiments, brain tissue that was collected at the end of delay showed increases in message or activation of putative markers of neuroplasticity (i.e., brain-derived neurotrophic factor, p38 mitogen-activated protein kinase, and cAMP response element-binding protein). These experiments demonstrate that prior administration of nonpressor doses of either ANG II or Aldo will induce salt sensitivity. Collectively, our findings indicate that treatment with subpressor doses of ANG II and Aldo initiate central neuroplastic changes that are involved in hypertension of different etiologies. Copyright © 2014 the American Physiological Society.

Biased and less sensitive: A gamified approach to delay discounting in heroin addiction.

PubMed

Scherbaum, Stefan; Haber, Paul; Morley, Kirsten; Underhill, Dylan; Moustafa, Ahmed A

2018-03-01

People with addiction will continue to use drugs despite adverse long-term consequences. We hypothesized (a) that this deficit persists during substitution treatment, and (b) that this deficit might be related not only to a desire for immediate gratification, but also to a lower sensitivity for optimal decision making. We investigated how individuals with a history of heroin addiction perform (compared to healthy controls) in a virtual reality delay discounting task. This novel task adds to established measures of delay discounting an assessment of the optimality of decisions, especially in how far decisions are influenced by a general choice bias and/or a reduced sensitivity to the relative value of the two alternative rewards. We used this measure of optimality to apply diffusion model analysis to the behavioral data to analyze the interaction between decision optimality and reaction time. The addiction group consisted of 25 patients with a history of heroin dependency currently participating in a methadone maintenance program; the control group consisted of 25 healthy participants with no history of substance abuse, who were recruited from the Western Sydney community. The patient group demonstrated greater levels of delay discounting compared to the control group, which is broadly in line with previous observations. Diffusion model analysis yielded a reduced sensitivity for the optimality of a decision in the patient group compared to the control group. This reduced sensitivity was reflected in lower rates of information accumulation and higher decision criteria. Increased discounting in individuals with heroin addiction is related not only to a generally increased bias to immediate gratification, but also to reduced sensitivity for the optimality of a decision. This finding is in line with other findings about the sensitivity of addicts in distinguishing optimal from nonoptimal choice options.

Reinforced Superhydrophobic Coating on Silicone Rubber for Longstanding Anti-Icing Performance in Severe Conditions.

PubMed

Emelyanenko, Alexandre M; Boinovich, Ludmila B; Bezdomnikov, Alexey A; Chulkova, Elizaveta V; Emelyanenko, Kirill A

2017-07-19

We present a simple method for fabricating the superhydrophobic coatings on composite silicone rubber used for electrical outdoor applications. The coating is characterized by contact angles as high as 170° and is mechanically durable in contact with the aqueous phase. We discuss the impact of mechanical durability of the surface texture on the anti-icing performance of the coating on the basis of the experimental data on freezing delay of sessile aqueous droplets. A set of complementary data obtained in laboratory and outdoor experiments on freezing delay time, variation of wettability and practical work of adhesion for supercooled aqueous sessile droplets, impacting behavior of droplets at low negative temperatures, as well as the results of snow and ice accumulation in outdoor experiments indicate the very prospective icephobic properties of the developed coating.

Mortality among PCR negative admitted Ebola suspects during the 2014/15 outbreak in Conakry, Guinea: A retrospective cohort study.

PubMed

Ingelbeen, Brecht; Bah, Elhadj Ibrahima; Decroo, Tom; Balde, Idrissa; Nordenstedt, Helena; van Griensven, Johan; De Weggheleire, Anja

2017-01-01

Non-cases are suspect Ebola Virus Disease (EVD) cases testing negative by EVD RT-PCR after admission to an Ebola Treatment Centre (ETC). Admitting non-cases to an ETC prompts concerns on case- and workload in the ETC, risk for nosocomial EVD infection, and delays in diagnosis and disease-specific treatment. We retrospectively analysed characteristics, outcomes and determinants of death of EVD cases and non-cases admitted to the Conakry ETC in Guinea between 03/2014 and 09/2015. Of the 2362 admitted suspects who underwent full confirmatory PCR testing, 1540 (65.2%) were non-cases; among them 727 needed repeated confirmatory PCR testing resulting in 2.5 days (average) in the ETC isolation ward. Twenty-one patients tested positive on the repeat test, most in a period of flawed sampling for the initial test and none after introduction of PCR confirmation with geneXpert. No readmissions following nosocomial EVD infection were recorded. No combination of symptoms yielded acceptable sensitivity and specificity to allow differentiating confirmed from non-cases. Symptoms as ocular bleeding/redness have high specificity, but limited usefulness as not common. Admission delay and age distribution were not different for both groups. In total, 98 (20.6%) of 475 deaths in the ETC were non-cases. Most died within 24 hours after admission. Living in Conakry (aOR 1.78 (1.08-2.96)) was the strongest risk factor for death. Weeks with higher admission load had lower case fatality among non-cases, probably because more acute (and treatable) illnesses of contacts of known cases were admitted. These findings show high numbers of potentially critically ill non-cases need to be considered when setting up triage and referral of EVD suspect cases. Symptoms and risk factors alone do not allow differentiating the non-cases. Integration of highly-sensitive EVD diagnostic methods with short turnaround time in the triage of peripheral hospitals and dropping the systematic 2nd PCR for symptomatic early presenters could limit delays in access to adapted care of cases and seriously ill non-cases. Whether feasible without compromising outbreak control, and under which conditions, should be further assessed.

Mortality among PCR negative admitted Ebola suspects during the 2014/15 outbreak in Conakry, Guinea: A retrospective cohort study

PubMed Central

Bah, Elhadj Ibrahima; Decroo, Tom; Balde, Idrissa; Nordenstedt, Helena; van Griensven, Johan; De Weggheleire, Anja

2017-01-01

Non-cases are suspect Ebola Virus Disease (EVD) cases testing negative by EVD RT-PCR after admission to an Ebola Treatment Centre (ETC). Admitting non-cases to an ETC prompts concerns on case- and workload in the ETC, risk for nosocomial EVD infection, and delays in diagnosis and disease-specific treatment. We retrospectively analysed characteristics, outcomes and determinants of death of EVD cases and non-cases admitted to the Conakry ETC in Guinea between 03/2014 and 09/2015. Of the 2362 admitted suspects who underwent full confirmatory PCR testing, 1540 (65.2%) were non-cases; among them 727 needed repeated confirmatory PCR testing resulting in 2.5 days (average) in the ETC isolation ward. Twenty-one patients tested positive on the repeat test, most in a period of flawed sampling for the initial test and none after introduction of PCR confirmation with geneXpert. No readmissions following nosocomial EVD infection were recorded. No combination of symptoms yielded acceptable sensitivity and specificity to allow differentiating confirmed from non-cases. Symptoms as ocular bleeding/redness have high specificity, but limited usefulness as not common. Admission delay and age distribution were not different for both groups. In total, 98 (20.6%) of 475 deaths in the ETC were non-cases. Most died within 24 hours after admission. Living in Conakry (aOR 1.78 (1.08–2.96)) was the strongest risk factor for death. Weeks with higher admission load had lower case fatality among non-cases, probably because more acute (and treatable) illnesses of contacts of known cases were admitted. These findings show high numbers of potentially critically ill non-cases need to be considered when setting up triage and referral of EVD suspect cases. Symptoms and risk factors alone do not allow differentiating the non-cases. Integration of highly-sensitive EVD diagnostic methods with short turnaround time in the triage of peripheral hospitals and dropping the systematic 2nd PCR for symptomatic early presenters could limit delays in access to adapted care of cases and seriously ill non-cases. Whether feasible without compromising outbreak control, and under which conditions, should be further assessed. PMID:28665950

Delay Discounting in C57BL/6J and DBA/2J Mice: Adolescent-Limited and Life-Persistent Patterns of Impulsivity

PubMed Central

Pinkston, Jonathan W.; Lamb, R. J.

2011-01-01

Impulsivity is a defining characteristic of adolescence. Compared to adults, for example, adolescents engage in higher rates of drug and alcohol experimentation, risky sexual practices, and criminal activity. Such behavior may reflect reduced sensitivity to long-term consequences for behavior during adolescence. Recently, our lab has attempted to refine mouse procedures to study developmental trends in decision making in the laboratory. In the present experiment, we examined sensitivity to delayed rewards in C57BL/6J (B6) and DBA/2J (D2) mice during adolescence and adulthood using an adaptation of a two-week delay discounting procedure developed by Adriani & Laviola (2003) [Behavioral Neuroscience, 117, 695-703]. During training, mice could choose between a 20- or 100-ul drop of milk delivered after a 1-s delay. During testing, the delay to the large drop of milk was increased from 1 to 100 seconds. As the delay to the larger volume increased, preference shifted to the smaller, more immediate option. In adolescence, both strains showed similar shifts in preference. In contrast, adult B6 mice were less sensitive to increasing delays than were adult D2 mice, who continued to perform much as their adolescent counterparts. A subsequent resistance-to-extinction test ruled out the possibility that the slower change in the adult B6 mice was due to perseverative responding. The present findings suggest that B6 and D2 strains may be differentially suited to uncovering the biological mechanism of short-term and long-term patterns of impulsive behavior. PMID:21463022

Lack of the purinergic receptor P2X7 results in resistance to contact hypersensitivity

PubMed Central

Weber, Felix C.; Esser, Philipp R.; Müller, Tobias; Ganesan, Jayanthi; Pellegatti, Patrizia; Simon, Markus M.; Zeiser, Robert; Idzko, Marco; Jakob, Thilo

2010-01-01

Sensitization to contact allergens requires activation of the innate immune system by endogenous danger signals. However, the mechanisms through which contact allergens activate innate signaling pathways are incompletely understood. In this study, we demonstrate that mice lacking the adenosine triphosphate (ATP) receptor P2X7 are resistant to contact hypersensitivity (CHS). P2X7-deficient dendritic cells fail to induce sensitization to contact allergens and do not release IL-1β in response to lipopolysaccharide (LPS) and ATP. These defects are restored by pretreatment with LPS and alum in an NLRP3- and ASC-dependent manner. Whereas pretreatment of wild-type mice with P2X7 antagonists, the ATP-degrading enzyme apyrase or IL-1 receptor antagonist, prevents CHS, IL-1β injection restores CHS in P2X7-deficient mice. Thus, P2X7 is a crucial receptor for extracellular ATP released in skin in response to contact allergens. The lack of P2X7 triggering prevents IL-1β release, which is an essential step in the sensitization process. Interference with P2X7 signaling may be a promising strategy for the prevention of allergic contact dermatitis. PMID:21059855

Predicting a contact's sensitivity to initial conditions using metrics of frictional coupling

DOE PAGES

Flicek, Robert C.; Hills, David A.; Brake, Matthew Robert W.

2016-09-29

This paper presents a method for predicting how sensitive a frictional contact’s steady-state behavior is to its initial conditions. Previous research has proven that if a contact is uncoupled, i.e. if slip displacements do not influence the contact pressure distribution, then its steady-state response is independent of initial conditions, but if the contact is coupled, the steady-state response depends on initial conditions. In this paper, two metrics for quantifying coupling in discrete frictional systems are examined. These metrics suggest that coupling is dominated by material dissimilarity due to Dundurs’ composite material parameter β when β ≥ 0.2, but geometric mismatchmore » becomes the dominant source of coupling for smaller values of β. Based on a large set of numerical simulations with different contact geometries, material combinations, and friction coefficients, a contact’s sensitivity to initial conditions is found to be correlated with the product of the coupling metric and the friction coefficient. For cyclic shear loading, this correlation is maintained for simulations with different contact geometries, material combinations, and friction coefficients. Furthermore, for cyclic bulk loading, the correlation is only maintained when the contact edge angle is held constant.« less

Predicting a contact's sensitivity to initial conditions using metrics of frictional coupling

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

Flicek, Robert C.; Hills, David A.; Brake, Matthew Robert W.

This paper presents a method for predicting how sensitive a frictional contact’s steady-state behavior is to its initial conditions. Previous research has proven that if a contact is uncoupled, i.e. if slip displacements do not influence the contact pressure distribution, then its steady-state response is independent of initial conditions, but if the contact is coupled, the steady-state response depends on initial conditions. In this paper, two metrics for quantifying coupling in discrete frictional systems are examined. These metrics suggest that coupling is dominated by material dissimilarity due to Dundurs’ composite material parameter β when β ≥ 0.2, but geometric mismatchmore » becomes the dominant source of coupling for smaller values of β. Based on a large set of numerical simulations with different contact geometries, material combinations, and friction coefficients, a contact’s sensitivity to initial conditions is found to be correlated with the product of the coupling metric and the friction coefficient. For cyclic shear loading, this correlation is maintained for simulations with different contact geometries, material combinations, and friction coefficients. Furthermore, for cyclic bulk loading, the correlation is only maintained when the contact edge angle is held constant.« less

Occupational allergic contact dermatitis and patch test results of leather workers at two Indonesian tanneries.

PubMed

Febriana, Sri Awalia; Jungbauer, Frank; Soebono, Hardyanto; Coenraads, Pieter-Jan

2012-11-01

Tannery workers are at considerable risk of developing occupational contact dermatitis. Occupational skin diseases in tannery workers in newly industrialized countries have been reported, but neither the prevalence of occupational allergic contact dermatitis nor the skin-sensitizing agents were specifically examined in those studies. To assess the prevalence of occupational allergic contact dermatitis in Indonesian tanneries, identify the causative allergens, and propose a tannery work series of patch test allergens. A cross-sectional study in all workers at two Indonesian tanneries was performed to assess the prevalence of occupational contact dermatitis via a questionnaire-based interview and skin examination. Workers with occupational contact dermatitis were patch tested to identify the causative allergens. Occupational contact dermatitis was suspected in 77 (16%) of the 472 workers. Thirteen (3%) of these 472 workers were confirmed to have occupational allergic contact dermatitis. Potassium dichromate (9.2%), N,N-diphenylguanidine (5.3%), benzidine (3.9%) and sodium metabisulfite (2.6%) were found to be the occupationally relevant sensitizers. The sensitization pattern showed some differences from the data in studies reported from other newly industrial countries. We compiled a 'tannery work series' of allergens for patch testing. A number of these allergens may also be considered for patch testing in patients with (leather) shoe dermatitis. © 2012 John Wiley & Sons A/S.

Study of the frequency of allergens in cosmetics components in patients with suspected allergic contact dermatitis.

PubMed

Silva, Eliane Aparecida; Bosco, Marcia Regina Miras; Mozer, Erika

2012-01-01

Contact dermatitis to cosmetics is a common dermatosis, especially in adults and professionals who handle them. The objective of this study was to evaluate the frequency of sensitization to cosmetics' components in patients with suspected allergic contact dermatitis and to identify the main sensitizers related to occupational contact dermatitis. During the period of January 2008 to June 2010, all the patients with a presumptive diagnosis of allergic contact dermatitis to cosmetics were selected. The patients were submitted to the patch tests of cosmetics series, composed by ten substances. Among the 147 patients studied sensitization to cosmetics components occurred in 31,29% of the cases, 14 of those (19,18%) equally corresponding to BHT and triethanolamine substances, 13 (17,81%) to ammonium thioglycolate, 09 to sorbic acid (12,33%), 08 to tosilamida (10,95%), 06 to germall (8,22%). The other elements tested showed indices of 5% or less. A higher frequency of contact dermatitis to cosmetics was observed in women and the age most affected was concordant with the age range of greatest professional activity of the population. Allergic contact dermatitis was more frequently associated with Triethanolamine, BHT and ammonium thioglycolate, and the relation with occupational contact dermatitis was discreet.

Defining the Value of Future Research to Identify the Preferred Treatment of Meniscal Tear in the Presence of Knee Osteoarthritis

PubMed Central

Losina, Elena; Dervan, Elizabeth E.; Paltiel, A. David; Dong, Yan; Wright, R. John; Spindler, Kurt P.; Mandl, Lisa A.; Jones, Morgan H.; Marx, Robert G.; Safran-Norton, Clare E.; Katz, Jeffrey N.

2015-01-01

Background Arthroscopic partial meniscectomy (APM) is extensively used to relieve pain in patients with symptomatic meniscal tear (MT) and knee osteoarthritis (OA). Recent studies have failed to show the superiority of APM compared to other treatments. We aim to examine whether existing evidence is sufficient to reject use of APM as a cost-effective treatment for MT+OA. Methods We built a patient-level microsimulation using Monte Carlo methods and evaluated three strategies: Physical therapy (‘PT’) alone; PT followed by APM if subjects continued to experience pain (‘Delayed APM’); and ‘Immediate APM’. Our subject population was US adults with symptomatic MT and knee OA over a 10 year time horizon. We assessed treatment outcomes using societal costs, quality-adjusted life years (QALYs), and calculated incremental cost-effectiveness ratios (ICERs), incorporating productivity costs as a sensitivity analysis. We also conducted a value-of-information analysis using probabilistic sensitivity analyses. Results Calculated ICERs were estimated to be $12,900/QALY for Delayed APM as compared to PT and $103,200/QALY for Immediate APM as compared to Delayed APM. In sensitivity analyses, inclusion of time costs made Delayed APM cost-saving as compared to PT. Improving efficacy of Delayed APM led to higher incremental costs and lower incremental effectiveness of Immediate APM in comparison to Delayed APM. Probabilistic sensitivity analyses indicated that PT had 3.0% probability of being cost-effective at a willingness-to-pay (WTP) threshold of $50,000/QALY. Delayed APM was cost effective 57.7% of the time at WTP = $50,000/QALY and 50.2% at WTP = $100,000/QALY. The probability of Immediate APM being cost-effective did not exceed 50% unless WTP exceeded $103,000/QALY. Conclusions We conclude that current cost-effectiveness evidence does not support unqualified rejection of either Immediate or Delayed APM for the treatment of MT+OA. The amount to which society would be willing to pay for additional information on treatment outcomes greatly exceeds the cost of conducting another randomized controlled trial on APM. PMID:26086246

Epidemic spreading and global stability of an SIS model with an infective vector on complex networks

NASA Astrophysics Data System (ADS)

Kang, Huiyan; Fu, Xinchu

2015-10-01

In this paper, we present a new SIS model with delay on scale-free networks. The model is suitable to describe some epidemics which are not only transmitted by a vector but also spread between individuals by direct contacts. In view of the biological relevance and real spreading process, we introduce a delay to denote average incubation period of disease in a vector. By mathematical analysis, we obtain the epidemic threshold and prove the global stability of equilibria. The simulation shows the delay will effect the epidemic spreading. Finally, we investigate and compare two major immunization strategies, uniform immunization and targeted immunization.

Contact stress sensor

DOEpatents

Kotovsky, Jack

2014-02-11

A method for producing a contact stress sensor that includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

Contact stress sensor

DOEpatents

Kotovsky, Jack [Oakland, CA

2012-02-07

A contact stress sensor includes one or more MEMS fabricated sensor elements, where each sensor element of includes a thin non-recessed portion, a recessed portion and a pressure sensitive element adjacent to the recessed portion. An electric circuit is connected to the pressure sensitive element. The circuit includes a thermal compensator and a pressure signal circuit element configured to provide a signal upon movement of the pressure sensitive element.

[Type IV contact allergies in the food processing industry: an update].

PubMed

Bauer, A; Schubert, S; Geier, J; Mahler, V

2018-06-01

The food sector is one of the high-risk areas for occupational irritative and allergic contact eczema. The present work provides an overview of the main allergens as well as sensitization frequencies and risk in various food industry occupations. The literature on type IV sensitization in the food sector is summarized. The relative risk of developing a work-related eczema in food processing is increased by more than 3 times. The comparison group was calculated on the basis of the proportion of documented cases in the IVDK (Informationsverbund Dermatologischer Kliniken) network per 100,000 working persons in relation to the average of the years 2005 and 2010. For this purpose, the average risk of all patients was set as reference to 1. Bakers, pastry chefs, cooks and meat and fish processors are mainly affected. In addition to irritant contact eczema, allergic contact eczema and protein contact dermatitis often occur. Leading haptens (main allergens) are rubber ingredients, but also disinfectants and compositae. Only a few contact allergens are responsible for the majority of job-relevant sensitizations in the food industry.

Speech Inconsistency in Children With Childhood Apraxia of Speech, Language Impairment, and Speech Delay: Depends on the Stimuli.

PubMed

Iuzzini-Seigel, Jenya; Hogan, Tiffany P; Green, Jordan R

2017-05-24

The current research sought to determine (a) if speech inconsistency is a core feature of childhood apraxia of speech (CAS) or if it is driven by comorbid language impairment that affects a large subset of children with CAS and (b) if speech inconsistency is a sensitive and specific diagnostic marker that can differentiate between CAS and speech delay. Participants included 48 children ranging between 4;7 to 17;8 (years;months) with CAS (n = 10), CAS + language impairment (n = 10), speech delay (n = 10), language impairment (n = 9), or typical development (n = 9). Speech inconsistency was assessed at phonemic and token-to-token levels using a variety of stimuli. Children with CAS and CAS + language impairment performed equivalently on all inconsistency assessments. Children with language impairment evidenced high levels of speech inconsistency on the phrase "buy Bobby a puppy." Token-to-token inconsistency of monosyllabic words and the phrase "buy Bobby a puppy" was sensitive and specific in differentiating children with CAS and speech delay, whereas inconsistency calculated on other stimuli (e.g., multisyllabic words) was less efficacious in differentiating between these disorders. Speech inconsistency is a core feature of CAS and is efficacious in differentiating between children with CAS and speech delay; however, sensitivity and specificity are stimuli dependent.

Effect of guar gum on hunger and satiety after meals of differing fat content: relationship with gastric emptying.

PubMed

French, S J; Read, N W

1994-01-01

To determine whether the satiating effects of fiber are due to delaying gastric emptying or slowing absorption of meals, 3% guar gum was added to high- and low-fat soups and gastric emptying rate, hunger, and satiety were measured in eight male volunteers. Guar gum delayed the emptying of the low-fat soup but the small delays in the return of hunger and decline of fullness were significantly correlated with the gastric emptying, suggesting mediation by gastric mechanoreceptors. The high-fat soup also emptied more slowly but this had no effect on the return of hunger or the decline in fullness. The delays in the return of hunger and decline of fullness were far greater when guar gum was added to the fatty soup; these delays were not correlated with the small additional delay in gastric emptying. This is more compatible with slowed absorption and prolonged contact of nutrients with intestinal chemoreceptors.

Effects of intrinsic stochasticity on delayed reaction-diffusion patterning systems.

PubMed

Woolley, Thomas E; Baker, Ruth E; Gaffney, Eamonn A; Maini, Philip K; Seirin-Lee, Sungrim

2012-05-01

Cellular gene expression is a complex process involving many steps, including the transcription of DNA and translation of mRNA; hence the synthesis of proteins requires a considerable amount of time, from ten minutes to several hours. Since diffusion-driven instability has been observed to be sensitive to perturbations in kinetic delays, the application of Turing patterning mechanisms to the problem of producing spatially heterogeneous differential gene expression has been questioned. In deterministic systems a small delay in the reactions can cause a large increase in the time it takes a system to pattern. Recently, it has been observed that in undelayed systems intrinsic stochasticity can cause pattern initiation to occur earlier than in the analogous deterministic simulations. Here we are interested in adding both stochasticity and delays to Turing systems in order to assess whether stochasticity can reduce the patterning time scale in delayed Turing systems. As analytical insights to this problem are difficult to attain and often limited in their use, we focus on stochastically simulating delayed systems. We consider four different Turing systems and two different forms of delay. Our results are mixed and lead to the conclusion that, although the sensitivity to delays in the Turing mechanism is not completely removed by the addition of intrinsic noise, the effects of the delays are clearly ameliorated in certain specific cases.

[Contact allergy to dexpanthenol].

PubMed

Schulze-Dirks, A; Frosch, P J

1988-06-01

Eleven cases of contact allergy to dexpanthenol are reported (5 females, 6 males; mean age 62.4 years). Five patients suffered from a leg ulcer and/or stasis dermatitis. In five patients the sensitization occurred after the application of dexpanthenol-containing ointments to the face. Only one patient did not show sensitization to other common allergens. Three patients were sensitive to wool wax alcohols, which are present in a commonly used product. Dexpanthenol seems to be a rare sensitizer, yet clinically most relevant for patients with stasis dermatitis and multiple allergies.

Differences in symptoms, first medical contact and pre-hospital delay times between patients with ST- and non-ST-elevation myocardial infarction.

PubMed

Ängerud, Karin H; Sederholm Lawesson, Sofia; Isaksson, Rose-Marie; Thylén, Ingela; Swahn, Eva

2017-11-01

In ST-elevation myocardial infarction, time to reperfusion is crucial for the prognosis. Symptom presentation in myocardial infarction influences pre-hospital delay times but studies about differences in symptoms between patients with ST-elevation myocardial infarction and non-ST-elevation myocardial infarction are sparse and inconclusive. The aim was to compare symptoms, first medical contact and pre-hospital delay times in patients with ST-elevation myocardial infarction and non-ST-elevation myocardial infarction. This multicentre, observational study included 694 myocardial infarction patients from five hospitals. The patients filled in a questionnaire about their pre-hospital experiences within 24 h of hospital admittance. Chest pain was the most common symptom in ST-elevation myocardial infarction and non-ST-elevation myocardial infarction (88.7 vs 87.0%, p=0.56). Patients with cold sweat (odds ratio 3.61, 95% confidence interval 2.29-5.70), jaw pain (odds ratio 2.41, 95% confidence interval 1.04-5.58), and nausea (odds ratio 1.70, 95% confidence interval 1.01-2.87) were more likely to present with ST-elevation myocardial infarction, whereas the opposite was true for symptoms that come and go (odds ratio 0.58, 95% confidence interval 0.38-0.90) or anxiety (odds ratio 0.52, 95% confidence interval 0.29-0.92). Use of emergency medical services was higher among patients admitted with ST-elevation myocardial infarction. The pre-hospital delay time from symptom onset to first medical contact was significantly longer in non-ST-elevation myocardial infarction (2:05 h vs 1:10 h, p=0.001). Patients with ST-elevation myocardial infarction differed from those with non-ST-elevation myocardial infarction regarding symptom presentation, ambulance utilisation and pre-hospital delay times. This knowledge is important to be aware of for all healthcare personnel and the general public especially in order to recognise symptoms suggestive of ST-elevation myocardial infarction and when to decide if there is a need for an ambulance.

Allergic contact dermatitis pattern in Kuwait: nickel leads the pack. In-depth analysis of nickel allergy based on the results from a large prospective patch test series report

PubMed Central

Almutawa, Fahad

2017-01-01

Introduction Contact dermatitis is a relatively common dermatosis reported among several population groups from all around the globe. However, the data from Kuwait is unavailable. Patch tests are essential for the diagnosis of contact sensitization. Aim To determine a relative frequency and pattern of sensitizers to different allergens in patients of suspected contact dermatitis in Kuwait and, also to study the role of the commonest sensitizer in detail. Material and methods Patch tests were performed in 2461 consecutive patients with a clinical diagnosis of contact dermatitis seen at our hospital between September 1, 2014 and August 31, 2015. Out of the total of 1381 (56.1%) patients with positive patch test results to at least one allergen, 546 (22.2%) patients with a single positive reaction to nickel only (single largest sensitizer) were selected as the study population for further detailed analysis. Results At least one positive patch test reaction was found in 1381 (56.12%) patients. Nickel was found to be the most common sensitizer seen in 546 (40%) patients. The mean age was 37.3 ±13.8 years and the mean duration of disease was 27.3 ±13.8 months. Most (387/546) patients sensitized were females. The forearms/hands and wrists were the most prevalent sites (52.56% of the participants). In 58.91% of women, dermatitis was more often confined to other sites, mostly ears and the neck due to earrings and necklaces. Just more than half of the number (51.09%) of nickel allergic patients were found in the age group of 15–25 years. Hairdressers/beauticians were the most affected group followed by house workers (housewives, cleaners, housekeepers). Conclusions Nickel is the single most common sensitizer found in our patients, and female sex, young age, occupation with long hours of contact to nickel are high risk factors. We recommend that a directive, which limits the release of nickel from products with extended skin contact, be approved in Kuwait. PMID:28670248

Dry Mouth? Don't Delay Treatment

MedlinePlus

... and use (metabolize) the sugar to grow. “A by-product of the metabolized sugar is acid, which starts ... Releases Consumer Updates About FDA Contact FDA Browse by Product Area Product Areas back Food Drugs Medical Devices ...

[When sunscreens do not help: allergic contact dermatitis to UV filters].

PubMed

Ludriksone, L; Tittelbach, J; Schliemann, S; Goetze, S; Elsner, P

2018-06-07

Ultraviolet (UV) filters may cause allergic and more frequently photoallergic contact dermatitis. Therefore, a photopach test should always be performed in case of a suspected contact sensitivity to UV filters. We report a case of a 65-year-old woman with a recurrent erythema of the face and décolleté after sun exposure despite application of a sunscreen. The (photo)patch test revealed a contact sensitivity to the UV filter butyl-methoxybenzoylmethane. Treatment with a topical glucocorticoid and avoidance of the particular UV filter led to a rapid improvement.

Acoustic method of investigating the material properties and humidity sensing behavior of polymer coated piezoelectric substrates

NASA Astrophysics Data System (ADS)

Caliendo, Cinzia

2006-09-01

The relative humidity (RH) sensing behavior of a polymeric film was investigated by means of polymer coated surface acoustic wave (SAW) delay lines implemented on single crystal piezoelectric substrates, such as quartz and LiNbO3, and on thin piezoelectric polycrystalline films, such as ZnO and AlN, on Si and GaAs. The same SAW delay line configuration was implemented on each substrate and the obtained devices' operating frequency was in the range of 105-156MHz, depending on the type of the substrate, on its crystallographic orientation, and on the SAW propagation direction. The surface of each SAW device was covered by the same type RH sensitive film of the same thickness and the RH sensitivity of each polymer coated substrate, i.e., the SAW relative phase velocity shift per RH unit changes, was investigated in the 0%—80% RH range. The perturbational approach was used to relate the SAW sensor velocity response to the RH induced changes in the physical parameters of the sensitive polymer film: the incremental change in the mass density and shear modulus of the polymer film per unit RH change were estimated. The shift of the bare SAW delay lines operating frequency induced by the presence of the polymer film, at RH =0% and at T =-10°C, allowed the experimental estimation of the mass sensitivity values of each substrate. These values were in good accordance with those reported in the literature and with those theoretically evaluated by exact numerical calculation. The shift of the bare SAW delay lines propagation loss induced by the polymer coating of the device surface, at RH =0% and at ambient temperature, allowed the experimental estimation of the elastic sensitivity of each substrate. These values were found in good accordance with those available from the literature. The temperature coefficient of delay and the electromechanical coupling coefficient of the bare substrates were also estimated. The membrane sensitivity to ethanol, methanol and isopropylic alcohol was tested by means of a high-frequency (670MHz) high-sensitivity Si /AlN resonator sensor.

Simultaneous Detection of Displacement, Rotation Angle, and Contact Pressure Using Sandpaper Molded Elastomer Based Triple Electrode Sensor

PubMed Central

Sul, Onejae; Lee, Seung-Beck

2017-01-01

In this article, we report on a flexible sensor based on a sandpaper molded elastomer that simultaneously detects planar displacement, rotation angle, and vertical contact pressure. When displacement, rotation, and contact pressure are applied, the contact area between the translating top elastomer electrode and the stationary three bottom electrodes change characteristically depending on the movement, making it possible to distinguish between them. The sandpaper molded undulating surface of the elastomer reduces friction at the contact allowing the sensor not to affect the movement during measurement. The sensor showed a 0.25 mm−1 displacement sensitivity with a ±33 μm accuracy, a 0.027 degree−1 of rotation sensitivity with ~0.95 degree accuracy, and a 4.96 kP−1 of pressure sensitivity. For possible application to joint movement detection, we demonstrated that our sensor effectively detected the up-and-down motion of a human forefinger and the bending and straightening motion of a human arm. PMID:28878166

Simultaneous Detection of Displacement, Rotation Angle, and Contact Pressure Using Sandpaper Molded Elastomer Based Triple Electrode Sensor.

PubMed

Choi, Eunsuk; Sul, Onejae; Lee, Seung-Beck

2017-09-06

In this article, we report on a flexible sensor based on a sandpaper molded elastomer that simultaneously detects planar displacement, rotation angle, and vertical contact pressure. When displacement, rotation, and contact pressure are applied, the contact area between the translating top elastomer electrode and the stationary three bottom electrodes change characteristically depending on the movement, making it possible to distinguish between them. The sandpaper molded undulating surface of the elastomer reduces friction at the contact allowing the sensor not to affect the movement during measurement. The sensor showed a 0.25 mm −1 displacement sensitivity with a ±33 μm accuracy, a 0.027 degree −1 of rotation sensitivity with ~0.95 degree accuracy, and a 4.96 kP −1 of pressure sensitivity. For possible application to joint movement detection, we demonstrated that our sensor effectively detected the up-and-down motion of a human forefinger and the bending and straightening motion of a human arm.

Solid state photon upconversion utilizing thermally activated delayed fluorescence molecules as triplet sensitizer

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

Wu, Tony C.; Congreve, Daniel N.; Baldo, Marc A., E-mail: baldo@mit.edu

2015-07-20

The ability to upconvert light is useful for a range of applications, from biological imaging to solar cells. But modern technologies have struggled to upconvert incoherent incident light at low intensities. Here, we report solid state photon upconversion employing triplet-triplet exciton annihilation in an organic semiconductor, sensitized by a thermally activated-delayed fluorescence (TADF) dye. Compared to conventional phosphorescent sensitizers, the TADF dye maximizes the wavelength shift in upconversion due to its small singlet-triplet splitting. The efficiency of energy transfer from the TADF dye is 9.1%, and the conversion yield of sensitizer exciton pairs to singlet excitons in the annihilator ismore » 1.1%. Our results demonstrate upconversion in solid state geometries and with non-heavy metal-based sensitizer materials.« less

The Influence of Perception on Maternal Sensitivity in Foster Care

ERIC Educational Resources Information Center

Ponciano, Leslie

2012-01-01

This study examined the association between perceptions of children's care needs and maternal sensitivity with 76 dyads in foster care. Foster mothers were more sensitive to typically developing children perceived as requiring easier care and were less sensitive to children with developmental delays. Adopting foster mothers were sensitive with…

Allergic contact dermatitis from resin hardeners during the manufacture of thermosetting coating paints.

PubMed

Foulds, I S; Koh, D

1992-02-01

5 production operators from 2 factories manufacturing thermosetting coating paint developed work-related skin disorders within 12 months of the introduction of a new powdered paint product. All 5 workers were found to have allergic contact dermatitis from 2 epoxy resin hardeners, both of which were commercial preparations of triglycidyl isocyanurate (TGIC). 2 of the workers had concomitant sensitization to epoxy resin in the standard series and several of the epoxy resin preparations at the workplace. TGIC has been reported as a contact sensitizer both in persons producing the chemical and among end-users of TGIC-containing products. These 5 reported cases document allergic contact dermatitis from commercial TGIC among exposed workers during an intermediate process of powdered paint manufacture. The possibility of substituting this epoxy resin hardener with less sensitizing alternatives should be explored.

Enhanced Contact Graph Routing (ECGR) MACHETE Simulation Model

NASA Technical Reports Server (NTRS)

Segui, John S.; Jennings, Esther H.; Clare, Loren P.

2013-01-01

Contact Graph Routing (CGR) for Delay/Disruption Tolerant Networking (DTN) space-based networks makes use of the predictable nature of node contacts to make real-time routing decisions given unpredictable traffic patterns. The contact graph will have been disseminated to all nodes before the start of route computation. CGR was designed for space-based networking environments where future contact plans are known or are independently computable (e.g., using known orbital dynamics). For each data item (known as a bundle in DTN), a node independently performs route selection by examining possible paths to the destination. Route computation could conceivably run thousands of times a second, so computational load is important. This work refers to the simulation software model of Enhanced Contact Graph Routing (ECGR) for DTN Bundle Protocol in JPL's MACHETE simulation tool. The simulation model was used for performance analysis of CGR and led to several performance enhancements. The simulation model was used to demonstrate the improvements of ECGR over CGR as well as other routing methods in space network scenarios. ECGR moved to using earliest arrival time because it is a global monotonically increasing metric that guarantees the safety properties needed for the solution's correctness since route re-computation occurs at each node to accommodate unpredicted changes (e.g., traffic pattern, link quality). Furthermore, using earliest arrival time enabled the use of the standard Dijkstra algorithm for path selection. The Dijkstra algorithm for path selection has a well-known inexpensive computational cost. These enhancements have been integrated into the open source CGR implementation. The ECGR model is also useful for route metric experimentation and comparisons with other DTN routing protocols particularly when combined with MACHETE's space networking models and Delay Tolerant Link State Routing (DTLSR) model.

Spot sign on 90-second delayed computed tomography angiography improves sensitivity for hematoma expansion and mortality: prospective study.

PubMed

Ciura, Viesha A; Brouwers, H Bart; Pizzolato, Raffaella; Ortiz, Claudia J; Rosand, Jonathan; Goldstein, Joshua N; Greenberg, Steven M; Pomerantz, Stuart R; Gonzalez, R Gilberto; Romero, Javier M

2014-11-01

The computed tomography angiography (CTA) spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage. The spot sign has proven to be a dynamic entity, with multimodal imaging proving to be of additional value. We investigated whether the addition of a 90-second delayed CTA acquisition would capture additional intracerebral hemorrhage patients with the spot sign and increase the sensitivity of the spot sign. We prospectively enrolled consecutive intracerebral hemorrhage patients undergoing first pass and 90-second delayed CTA for 18 months at a single academic center. Univariate and multivariate logistic regression were performed to assess clinical and neuroimaging covariates for relationship with hematoma expansion and mortality. Sensitivity of the spot sign for hematoma expansion on first pass CTA was 55%, which increased to 64% if the spot sign was present on either CTA acquisition. In multivariate analysis the spot sign presence was associated with significant hematoma expansion: odds ratio, 17.7 (95% confidence interval, 3.7-84.2; P=0.0004), 8.3 (95% confidence interval, 2.0-33.4; P=0.004), and 12.0 (95% confidence interval, 2.9-50.5; P=0.0008) if present on first pass, delayed, or either CTA acquisition, respectively. Spot sign presence on either acquisitions was also significant for mortality. We demonstrate improved sensitivity for predicting hematoma expansion and poor outcome by adding a 90-second delayed CTA, which may enhance selection of patients who may benefit from hemostatic therapy. © 2014 American Heart Association, Inc.

Cases of death caused by gas or warning firearms.

PubMed

Rothschild, M A; Maxeiner, H; Schneider, V

1994-01-01

Five cases of lethal injuries caused by gas or warning firearms are discussed. In one suicide case a modified weapon (elongated barrel) and steel bullets were used to fire a shot into the head, the bullets lodged in the skull and lethal bleeding resulted. In the other cases conventional gas weapons without evidence of alteration were used for contact shots; injuries were caused by the effect of propelling powder gases. Two of these cases were suicides (temporal contact shot and back of the neck contact shot), one was an accident (inguinal contact shot with lethal bleeding), and one was an attack by another person with a contact shot against the neck with bilateral tears of the hypopharynx. After successful surgery, a delayed death occurred 12 days later caused by bleeding into the airways from the ruptured external carotid artery.

[Hereditary hemochromatosis: presenting manifestations and diagnostic delay].

PubMed

Gasser, B; Courtois, F; Hojjat-Assari, S; Sauleau, E A; Buffet, C; Brissot, P

2014-03-01

Hereditary hemochromatosis is characterized by an excessive absorption and progressive accumulation of iron in the liver, the pancreas, the heart, and the joints. Tiredness and joint manifestations occur usually before hepatopathy, diabetes or cardiopathy. Such common and unspecific symptoms seem to be largely unknown and important diagnostic delays have been reported. The aim of this study was to investigate the discovery circumstances and the diagnostic delay. A survey was carried out amongst French patients with C282Y homozygous hemochromatosis who were contacted through patients associations or blood centers. The questionnaire was answered by 374 patients. Mean age at diagnosis was 48.6±11.9years. In 53% of the cases, the serum level of ferritin was greater than 1000 μg/L. Diagnosis was based on family genetic survey (29%), or fortuitous analyses showing an abnormal serum ferritin (26%), or clinical manifestations (45%). Main complaints were joint pain, tiredness or liver disease. Only 2.1% consulted for diabetes, cardiopathy or changed complexion. Time to diagnosis was lower than 1 year for 98% of patients who presented with fatigue but from 1 to 15 years for 23.4% and 29% of patients who presented with arthropathy and hepatopathy, respectively. For 55% of patients, diagnosis was based on familial genetic survey or fortuitous abnormal results of blood samples. An initial serum level of ferritin greater than 1000 μg/L was a factor of severity for 50% of patient. These two elements must be taken into account to consider a population mass screening. Long time to diagnosis required a sensitization of the population to be aware of the clinical manifestations of hemochromatosis. Copyright © 2013 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Design of teleoperation system with a force-reflecting real-time simulator

NASA Technical Reports Server (NTRS)

Hirata, Mitsunori; Sato, Yuichi; Nagashima, Fumio; Maruyama, Tsugito

1994-01-01

We developed a force-reflecting teleoperation system that uses a real-time graphic simulator. This system eliminates the effects of communication time delays in remote robot manipulation. The simulator provides the operator with predictive display and feedback of computed contact forces through a six-degree of freedom (6-DOF) master arm on a real-time basis. With this system, peg-in-hole tasks involving round-trip communication time delays of up to a few seconds were performed at three support levels: a real image alone, a predictive display with a real image, and a real-time graphic simulator with computed-contact-force reflection and a predictive display. The experimental results indicate the best teleoperation efficiency was achieved by using the force-reflecting simulator with two images. The shortest work time, lowest sensor maximum, and a 100 percent success rate were obtained. These results demonstrate the effectiveness of simulated-force-reflecting teleoperation efficiency.

Control of complex components with Smart Flexible Phased Arrays.

PubMed

Casula, O; Poidevin, C; Cattiaux, G; Dumas, Ph

2006-12-22

The inspection is mainly performed in contact with ultrasonic wedge transducers; However, the shape cannot fit the changing geometries of components (butt weld, nozzle, elbow). The variable thickness of the coupling layer, between the wedge and the local surface, leads to beam distortions and losses of sensitivity. Previous studies have shown that these two phenomena contribute to reduce the inspection performances leading to shadow area, split beam.... Flexible phased arrays have been developed to fit the complex profile and improve such controls. The radiating surface is composed with independent piezoelectric elements mechanically assembled and a profilometer, embedded in the transducer, measures the local distortion. The computed shape is used by an algorithm to compute in real-time the adapted delay laws compensating the distortions of 2D or 3D profiles. Those delay laws are transferred to the real-time UT acquisition system, which applies them to the piezoelectric elements. This self-adaptive process preserves, during the scanning, the features of the focused beam (orientation and focal depth) in the specimen. To validate the concept of the Smart Flexible Phased Array Transducer, prototypes have been integrated to detect flaws machined in mock-ups with realistic irregular 2D and 3D shapes. Inspections have been carried out on samples showing the enhancement performances of the "Smart Flexible Phased Array" and validating the mechanical and acoustical behaviors of these probes.

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

Sarshar, Mohammad Amin; Swarctz, Christopher; Hunter, Scott Robert

In this paper, the iceophobic properties of superhydrophobic surfaces are investigated under dynamic flow conditions by using a closed loop low-temperature wind tunnel. Superhydrophobic surfaces were prepared by coating the substrates of aluminum and steel plates with nano-structured hydrophobic particles. The superhydrophobic plates along with uncoated control ones were exposed to an air flow of 12 m/s and 20 F accompanying micron-sized water droplets in the icing wind tunnel and the ice formation and accretion were probed by high-resolution CCD cameras. Results show that the superhydrophobic coatings significantly delay the ice formation and accretion even under the dynamic flow conditionmore » of the highly energetic impingement of accelerated super-cooled water droplets. It is found that there is a time scale for this phenomenon (delay of the ice formation) which has a clear correlation with the contact angle hysteresis and the length scale of surface roughness of the superhydrophobic surface samples, being the highest for the plate with the lowest contact angle hysteresis and finer surface roughness. The results suggest that the key parameter for designing iceophobic surfaces is to retain a low contact angle hysteresis (dynamic property) and the non-wetting superhydrophobic state under the hydrodynamic pressure of impinging droplets, rather than to only have a high contact angle (static property), in order to result in efficient anti-icing properties under dynamic conditions such as forced flows.« less

Contact urticaria from carboxymethylcellulose in white chalk.

PubMed

Moreau, Linda; Alomer, Ghanima; Dubé, Normand; Sasseville, Denis

2006-03-01

Carboxymethylcellulose (CMC) is widely used in consumer goods, foods, and medicaments as a binder, emulsifier, and viscosity enhancer. Cases of immediate and delayed allergic reactions to this anionic cellulose polymer have been reported. To report a case of contact urticaria from CMC in chalk, with possible cross-reaction to methyl hydroxyethylcellulose (MHEC). Patch tests with readings at 48 and 96 hours were performed with the North American Contact Dermatitis Group standard series and benzisothiazolinone. Open and prick tests with readings after 30 minutes were performed with two brands of chalk as well as with various petrolatum and aqueous dilutions of CMC, MHEC, oleic acid, and calcium carbonate. The patient developed strong urticarial reactions during open tests with both powdered chalks and had milder reactions to the open test with CMC 10% aqueous (aq) and to prick testing with CMC 0.1% aq. No reaction to MHEC or any of the other ingredients of the chalks was observed. No relevant delayed reaction was noted. CMC can cause contact urticaria. It remains unclear why our patient reacted more strongly to the chalk than to CMC itself. We speculate that the abrasive nature of the chalk enhances the cutaneous penetration of CMC or that calcium carbonate, the main ingredient of the chalk, acts as an adjuvant. It is also possible that CMC and MHEC cross-react and that our negative results with MHEC may be due to improper testing technique or concentrations.

Aldosterone acting through the central nervous system sensitizes angiotensin II-induced hypertension.

PubMed

Xue, Baojian; Zhang, Zhongming; Roncari, Camila F; Guo, Fang; Johnson, Alan Kim

2012-10-01

Previous studies have shown that preconditioning rats with a nonpressor dose of angiotensin II (Ang II) sensitizes the pressor response produced by later treatment with a higher dose of Ang II and that Ang II and aldosterone (Aldo) can modulate each other's pressor effects through actions involving the central nervous system. The current studies tested whether Aldo can cross-sensitize the pressor actions of Ang II to enhance hypertension by employing an induction-delay-expression experimental design. Male rats were implanted for telemetered blood pressure recording. During induction, subpressor doses of either subcutaneous or intracerebroventricular Aldo were delivered for 1 week. Rats were then rested for 1 week (delay) to assure that any exogenous Aldo was metabolized. After this, Ang II was given subcutaneously for 2 weeks (expression). During induction and delay, Aldo had no sustained effect on blood pressure. However, during expression, Ang II-induced hypertension was greater in the groups receiving subcutaneous or intracerebroventricular Aldo during induction in comparison with those groups receiving vehicle. Central administration of mineralocorticoid receptor antagonist blocked sensitization. Brain tissue collected at the end of delay and expression showed increased mRNA expression of several renin-angiotensin-aldosterone system components in cardiovascular-related forebrain regions of cross-sensitized rats. Cultured subfornical organ neurons preincubated with Aldo displayed greater increases in [Ca2+]i after Ang II treatment, and there was a greater Fra-like immunoreactivity present at the end of expression in cardiovascular-related forebrain structures. Taken together, these results indicate that Aldo pretreatment cross-sensitizes the development of Ang II-induced hypertension probably by mechanisms that involve the central nervous system.

Skin, Hair, and Nails

MedlinePlus

... as asthma and seasonal, environmental, and food allergies. Contact dermatitis. This occurs when the skin comes into contact ... or sensitive to. The best-known cause of contact dermatitis is poison ivy, but there are many others, ...

Patch test results of the dental personnel with contact dermatitis.

PubMed

Kocak, Oguzhan; Gul, Ulker

2014-12-01

Dental personnel have high risk of occupational contact dermatitis. The aim of this study is to detect the materials which cause contact sensitization and the frequency of contact dermatitis by using patch tests with European standard series and dental screening series in dental personnel. Between August 2008 and July 2009, 461 dental personnel working in Ankara (Turkey) were examined and age, gender, previous history of dermatitis, area of the skin affected and clinical diagnosis were noted. About 198 (43%) of the dental personnel were diagnosed contact dermatitis. Sixty-five of the dental personnel accepted to be patch tested. Dental technicians, dentists and dental nurses constitute 69.2%, 24.6% and 6.2% of patch tested 65 patients, respectively. Positive reactions to at least one allergen were detected with European standard series at 20% and with dental series at 10.8% among the dental personnel. The most common allergens were nickel sulfate (12.3%), acrylates (6.1%) and para-tertiary-butylphenol-formaldehyde resin (4.6%). The most common acrylate was ethyleneglycol dimethacrylate (3.1%). We believe our study will be helpful to dermatologists about frequency of contact dermatitis among dental personnel and allergens that cause contact sensitivity for developing new methods to protect the personnel in dentistry against sensitization.

Reduction technique for tire contact problems

NASA Technical Reports Server (NTRS)

Noor, Ahmed K.; Peters, Jeanne M.

1995-01-01

A reduction technique and a computational procedure are presented for predicting the tire contact response and evaluating the sensitivity coefficients of the different response quantities. The sensitivity coefficients measure the sensitivity of the contact response to variations in the geometric and material parameters of the tire. The tire is modeled using a two-dimensional laminated anisotropic shell theory with the effects of variation in geometric and material parameters, transverse shear deformation, and geometric nonlinearities included. The contact conditions are incorporated into the formulation by using a perturbed Lagrangian approach with the fundamental unknowns consisting of the stress resultants, the generalized displacements, and the Lagrange multipliers associated with the contact conditions. The elemental arrays are obtained by using a modified two-field, mixed variational principle. For the application of the reduction technique, the tire finite element model is partitioned into two regions. The first region consists of the nodes that are likely to come in contact with the pavement, and the second region includes all the remaining nodes. The reduction technique is used to significantly reduce the degrees of freedom in the second region. The effectiveness of the computational procedure is demonstrated by a numerical example of the frictionless contact response of the space shuttle nose-gear tire, inflated and pressed against a rigid flat surface.

Value of evidence from syndromic surveillance with cumulative evidence from multiple data streams with delayed reporting.

PubMed

Struchen, R; Vial, F; Andersson, M G

2017-04-26

Delayed reporting of health data may hamper the early detection of infectious diseases in surveillance systems. Furthermore, combining multiple data streams, e.g. aiming at improving a system's sensitivity, can be challenging. In this study, we used a Bayesian framework where the result is presented as the value of evidence, i.e. the likelihood ratio for the evidence under outbreak versus baseline conditions. Based on a historical data set of routinely collected cattle mortality events, we evaluated outbreak detection performance (sensitivity, time to detection, in-control run length) under the Bayesian approach among three scenarios: presence of delayed data reporting, but not accounting for it; presence of delayed data reporting accounted for; and absence of delayed data reporting (i.e. an ideal system). Performance on larger and smaller outbreaks was compared with a classical approach, considering syndromes separately or combined. We found that the Bayesian approach performed better than the classical approach, especially for the smaller outbreaks. Furthermore, the Bayesian approach performed similarly well in the scenario where delayed reporting was accounted for to the scenario where it was absent. We argue that the value of evidence framework may be suitable for surveillance systems with multiple syndromes and delayed reporting of data.

A hypothesis for delayed dynamic earthquake triggering

USGS Publications Warehouse

Parsons, T.

2005-01-01

It's uncertain whether more near-field earthquakes are triggered by static or dynamic stress changes. This ratio matters because static earthquake interactions are increasingly incorporated into probabilistic forecasts. Recent studies were unable to demonstrate all predictions from the static-stress-change hypothesis, particularly seismicity rate reductions. However, current dynamic stress change hypotheses do not explain delayed earthquake triggering and Omori's law. Here I show numerically that if seismic waves can alter some frictional contacts in neighboring fault zones, then dynamic triggering might cause delayed triggering and an Omori-law response. The hypothesis depends on faults following a rate/state friction law, and on seismic waves changing the mean critical slip distance (Dc) at nucleation zones.

Mobile technology habits: patterns of association among device usage, intertemporal preference, impulse control, and reward sensitivity.

PubMed

Wilmer, Henry H; Chein, Jason M

2016-10-01

Mobile electronic devices are playing an increasingly pervasive role in our daily activities. Yet, there has been very little empirical research investigating how mobile technology habits might relate to individual differences in cognition and affect. The research presented in this paper provides evidence that heavier investment in mobile devices is correlated with a relatively weaker tendency to delay gratification (as measured by a delay discounting task) and a greater inclination toward impulsive behavior (i.e., weaker impulse control, assessed behaviorally and through self-report) but is not related to individual differences in sensitivity to reward. Analyses further demonstrated that individual variation in impulse control mediates the relationship between mobile technology usage and delay of gratification. Although based on correlational results, these findings lend some backing to concerns that increased use of portable electronic devices could have negative impacts on impulse control and the ability to appropriately valuate delayed rewards.

Two vicious circles contributing to a diagnostic delay for tuberculosis patients in Arkhangelsk

PubMed Central

Kuznetsov, Vladimir N.; Grjibovski, Andrej M.; Mariandyshev, Andrej O.; Johansson, Eva; Bjune, Gunnar A.

2014-01-01

Setting Delay in tuberculosis (TB) diagnosis increases the infectious pool in the community and the risk of development of resistance of mycobacteria, which results in an increased number of deaths. Objective To describe patients’ and doctors’ perceptions of diagnostic delay in TB patients in the Arkhangelsk region and to develop a substantive model to better understand the mechanisms of how these delays are linked to each other. Design A grounded theory approach was used to study the phenomenon of diagnostic delay. Patients with TB diagnostic delay and doctors–phthisiatricians were interviewed. Results A model named ‘sickness trajectory in health-seeking behaviour among tuberculosis patients’ was developed and included two core categories describing two vicious circles of diagnostic delay in patients with TB: ‘limited awareness of the importance to contact the health system’ and ‘limited resources of the health system’ and the categories: ‘factors influencing health-seeking behaviour’ and ‘factors influencing the health system effectiveness’. Men were more likely to report patient delay, while women were more likely to report health system delay. Conclusions To involve people in early medical examinations, it is necessary to increase alertness on TB among patients and to improve health systems in the districts. PMID:25163673

Photophobia

MedlinePlus

... sensitivity; Vision - light sensitive; Eyes - sensitivity to light Images External and internal eye anatomy References Ehlers W, Suchecki J, Steinemann TL, Donshik P. Contact lens-related complications. ...

Lunar Reconnaissance Orbiter Contamination Sensitivity Training

NASA Technical Reports Server (NTRS)

Rivera, Rachel

2007-01-01

The following packet is a contamination control training intended for personnel handling or coming to contact with Lunar Reconnaissance Or biter (LRO) flight hardware. This training is being implemented to f amiliarize personnel, coming into contact with LRO hardware, what its contamination sensitivities are and what can be done by all to maint ain its cleanliness levels.

Heritability Maps May Hold Clues to Delayed Onset of Mental Disorders

MedlinePlus

... Office 301-443-4536 NIMHpress@nih.gov More Science News about Brain Anatomy and Physiology Genetics Contact ... the Field News from the Field NIMH-Funded Science on EurekAlert Researchers find clues to treating psychoses ...

Canine left ventricle electromechanical behavior under different pacing modes.

PubMed

Vo Thang, Thanh-Thuy; Thibault, Bernard; Finnerty, Vincent; Pelletier-Galarneau, Matthieu; Khairy, Paul; Grégoire, Jean; Harel, François

2012-10-01

Cardiac resynchronization therapy may improve survival and quality of life in patients suffering from heart failure with left ventricular (LV) contraction dyssynchrony. While several studies have investigated electrical or mechanical determinants of synchronous contraction, few have focused on activation contraction coupling at a macroscopic level. The objective of the study was to characterize LV electromechanical behavior and response to pacing in a heart failure model. We analyzed data from 3D electroanatomic non-contact mapping and blood pool SPECT for 12 dogs with right ventricular (RV) tachycardia pacing-induced dilated cardiomyopathy. Surfaces generated by the two modalities were registered. Electrical signals were analyzed, and endocardial wall displacement curves were portrayed. Rapid pacing decreased the mean LV ejection fraction (LVEF) to 20.9 % and prolonged the QRS duration to 79 ± 10 ms (normal range: 40-50 ms). QRS duration remained unchanged with biventricular pacing (88.5 ms), while single site pacing further prolonged the QRS duration (113.3 ms for RV pacing and 111.6 ms for LV pacing). No trend was observed in LV systolic function. Activation duration time was significantly increased with all pacing modes compared to baseline. Finally, electromechanical delay, as defined by the delay between electrical activation and mechanical response, was increased by single site pacing (172.9 ms for RV pacing and 174.6 ms for LV pacing) but not by biventricular pacing (162.4 ms). Combined temporal and spatial coregistration electroanatomic maps and baseline gated blood pool SPECT imaging allowed us to quantify activation duration time, electromechanical delay, and LVEF for different pacing modes. Even if pacing modes did not significantly modify LVEF or activation duration, they produced alterations in electromechanical delay, with biventricular pacing significantly decreasing the electromechanical delay as measured by surface tracings and endocardial non-contact mapping.

Contact sensitivity to preservatives in Singapore: frequency of sensitization to 11 common preservatives 2006-2011.

PubMed

Cheng, Suzanne; Leow, Yung Hian; Goh, Chee Leok; Goon, Anthony

2014-01-01

Preservatives are indispensable agents used to prevent bacterial and fungal contamination of cosmetics, personal care products, domestic preparations, and industrial products. We evaluated patch-test data at the National Skin Centre, Singapore, from 2006 to 2011 to identify the trends in preservative contact allergies. All patients with suspected contact dermatitis were patch tested to 4 preservatives within the modified European standard series. Patients were also tested with 7 preservatives from our special series if clinically indicated. Three thousand one hundred seventy-seven patients were tested to preservatives in the standard series. Sensitization frequencies were all greater than 1%: parabens (2.58%), methylchloroisothiazolinone/methylisothiazolinone (1.75%), quaternium 15 (1.43%), and methyldibromoglutaronitrile (1.2%). There was no change in trends in sensitization frequencies from 2006 to 2011, with no increase in sensitization frequency to methylchloroisothiazolinone/methylisothiazolinone. The sensitization frequencies for methyldibromoglutaronitrile/phenoxyethanol and diazolidinylurea were 2.03% and 1.37%, respectively, and remained less than 1% for bronopol, imidazolidinyl urea, and 2-phenoxyethanol. A rate of 0% was seen for 1,3-dimethylol-5,5-dimethyl hydantoin and formaldehyde; 9.4% of positive patch-test results became positive only at day 7. Preservatives are common causes of allergic contact dermatitis. This should be considered when introducing new preservatives into the market. Day 7 readings are important to detect late reactions.

Progress on Reconstructed Human Skin Models for Allergy Research and Identifying Contact Sensitizers.

PubMed

Rodrigues Neves, Charlotte; Gibbs, Susan

2018-06-23

Contact with the skin is inevitable or desirable for daily life products such as cosmetics, hair dyes, perfumes, drugs, household products, and industrial and agricultural products. Whereas the majority of these products are harmless, a number can become metabolized and/or activate the immunological defense via innate and adaptive mechanisms resulting in sensitization and allergic contact dermatitis upon following exposures to the same substance. Therefore, strict safety (hazard) assessment of actives and ingredients in products and drugs applied to the skin is essential to determine I) whether the chemical is a potential sensitizer and if so II) what is the safe concentration for human exposure to prevent sensitization from occurring. Ex vivo skin is a valuable model for skin penetration studies but due to logistical and viability limitations the development of in vitro alternatives is required. The aim of this review is to give a clear overview of the organotypic in vitro skin models (reconstructed human epidermis, reconstructed human skin, immune competent skin models incorporating Langerhans Cells and T-cells, skin-on-chip) that are currently commercially available or which are being used in a laboratory research setting for hazard assessment of potential sensitizers and for investigating the mechanisms (sensitization key events 1-4) related to allergic contact dermatitis. The limitations of the models, their current applications, and their future potential in replacing animals in allergy-related science are discussed.

Time delay in atomic photoionization with circularly polarized light

NASA Astrophysics Data System (ADS)

Ivanov, I. A.; Kheifets, A. S.

2013-03-01

We study time delay in atomic photoionization by circularly polarized light. By considering the Li atom in an excited 2p state, we demonstrate a strong time-delay asymmetry between the photoemission of the target electrons that are co- and counter-rotating with the electromagnetic field in the polarization plane. In addition, we observe the time-delay sensitivity to the polar angle of the photoelectron emission in the polarization plane. This modulation depends on the shape and duration of the electromagnetic pulse.

Time-resolved delayed luminescence image microscopy using an europium ion chelate complex.

PubMed Central

Marriott, G.; Heidecker, M.; Diamandis, E. P.; Yan-Marriott, Y.

1994-01-01

Improvements and extended applications of time-resolved delayed luminescence imaging microscopy (TR-DLIM) in cell biology are described. The emission properties of europium ion complexed to a fluorescent chelating group capable of labeling proteins are exploited to provide high contrast images of biotin labeled ligands through detection of the delayed emission. The streptavidin-based macromolecular complex (SBMC) employs streptavidin cross-linked to thyroglobulin multiply labeled with the europium-fluorescent chelate. The fluorescent chelate is efficiently excited with 340-nm light, after which it sensitizes europium ion emission at 612 nm hundreds of microseconds later. The SBMC complex has a high quantum yield orders of magnitude higher than that of eosin, a commonly used delayed luminescent probe, and can be readily seen by the naked eye, even in specimens double-labeled with prompt fluorescent probes. Unlike triplet-state phosphorescent probes, sensitized europium ion emission is insensitive to photobleaching and quenching by molecular oxygen; these properties have been exploited to obtain delayed luminescence images of living cells in aerated medium thus complementing imaging studies using prompt fluorescent probes. Since TR-DLIM has the unique property of rejecting enormous signals that originate from scattered light, autofluorescence, and prompt fluorescence it has been possible to resolve double emission images of living amoeba cells containing an intensely stained lucifer yellow in pinocytosed vesicles and membrane surface-bound SBMC-labeled biotinylated concanavalin A. Images of fixed cells represented in terms of the time decay of the sensitized emission show the lifetime of the europium ion emission is sensitive to the environment in which it is found. Through the coupling of SBMC to streptavidin,a plethora of biotin-based tracer molecules are available for immunocytochemical studies. Images FIGURE 1 FIGURE 2 FIGURE 3 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:7811952

Experimental and numerical investigation of crack initiation and propagation in silicon nitride ceramic under rolling and cyclic contact

NASA Astrophysics Data System (ADS)

Raga, Rahul; Khader, Iyas; Zdeněk, Chlup; Kailer, Andreas

2017-05-01

The focus of the work was to investigate crack initiation and propagation mechanisms in silicon nitride undergoing non-conforming hybrid contact under various tribological conditions. In order to understand the prevailing modes of damage in silicon nitride, two distinct model experiments were proposed, namely, rolling contact and cyclic contact experiments. The rolling contact experiment was designed in order to mimic the contact conditions appearing in hybrid bearings at contact pressures ranging from 3 to 6 GPa. On the other hand, cyclic contact experiments with stresses ranging from 4 to 15 GPa under different media were carried out to study damage under localised stresses. In addition, the experimentally observed cracks were implemented in a finite element model to study the stress redistribution and correlate the generated stresses with the corresponding mechanisms. Crack propagation under rolling contact was attributed to two different mechanisms, namely, fatigue induced fracture and lubricant driven crack propagation. The numerical simulations shed light on the tensile stress driven surface and subsurface crack propagation mechanisms. On the other hand, the cyclic contact experiments showed delayed crack formation for lubricated cyclic contact. Ceramographic cross-sectional analysis showed crack patterns similar to Hertzian crack propagation under cyclic contact load.

Genes Activated by Vibrio cholerae upon Exposure to Caenorhabditis elegans Reveal the Mannose-Sensitive Hemagglutinin To Be Essential for Colonization.

PubMed

List, Cornelia; Grutsch, Andreas; Radler, Claudia; Cakar, Fatih; Zingl, Franz G; Schild-Prüfert, Kristina; Schild, Stefan

2018-01-01

During its life cycle, the facultative human pathogen Vibrio cholerae , which is the causative agent of the diarrheal disease cholera, needs to adapt to a variety of different conditions, such as the human host or the aquatic environment. Importantly, cholera infections originate from the aquatic reservoir where V. cholerae persists between the outbreaks. In the aquatic environment, bacteria are constantly threatened by predatory protozoa and nematodes, but our knowledge of the response pathways and adaptation strategies of V. cholerae to such stressors is limited. Using a temporally controlled reporter system of transcription, we identified more than 100 genes of V. cholerae induced upon exposure to the nematode Caenorhabditis elegans , which emerged recently as a valuable model for environmental predation during the aquatic lifestyle of V. cholerae Besides others, we identified and validated the genes encoding the mannose-sensitive hemagglutinin (MSHA) type IV pilus to be significantly induced upon exposure to the nematode. Subsequent analyses demonstrated that the mannose-sensitive hemagglutinin is crucial for attachment of V. cholerae in the pharynx of the worm and initiation of colonization, which results in growth retardation and developmental delay of C. elegans Thus, the surface adhesion factor MSHA could be linked to a fitness advantage of V. cholerae upon contact with bacterium-grazing nematodes. IMPORTANCE The waterborne diarrheal disease cholera is caused by the bacterium Vibrio cholerae The facultative human pathogen persists as a natural inhabitant in the aquatic ecosystem between outbreaks. In contrast to the human host, V. cholerae requires a different set of genes to survive in this hostile environment. For example, predatory micrograzers are commonly found in the aquatic environment and use bacteria as a nutrient source, but knowledge of the interaction between bacterivorous grazers and V. cholerae is limited. In this study, we successfully adapted a genetic reporter technology and identified more than 100 genes activated by V. cholerae upon exposure to the bacterium-grazing nematode Caenorhabditis elegans This screen provides a first glimpse into responses and adaptational strategies of the bacterial pathogen against such natural predators. Subsequent phenotypic characterization revealed the mannose-sensitive hemagglutinin to be crucial for colonization of the worm, which causes developmental delay and growth retardation. Copyright © 2018 List et al.

Delay-induced cluster patterns in coupled Cayley tree networks

NASA Astrophysics Data System (ADS)

Singh, A.; Jalan, S.

2013-07-01

We study effects of delay in diffusively coupled logistic maps on the Cayley tree networks. We find that smaller coupling values exhibit sensitiveness to value of delay, and lead to different cluster patterns of self-organized and driven types. Whereas larger coupling strengths exhibit robustness against change in delay values, and lead to stable driven clusters comprising nodes from last generation of the Cayley tree. Furthermore, introduction of delay exhibits suppression as well as enhancement of synchronization depending upon coupling strength values. To the end we discuss the importance of results to understand conflicts and cooperations observed in family business.

Postplacental or Delayed Insertion of the Levonorgestrel Intrauterine Device After Vaginal Delivery

PubMed Central

Chen, Beatrice A.; Reeves, Matthew F.; Hayes, Jennifer L.; Hohmann, Heather L.; Perriera, Lisa K.; Creinin, Mitchell D.

2011-01-01

OBJECTIVE To estimate whether 6-month use of the levonorgestrel-releasing intrauterine device (IUD) would be higher when insertion occurred within 10 minutes of placental delivery compared with 6–8 weeks postpartum. METHODS We enrolled pregnant women planning vaginal deliveries and desiring a postpartum levonorgestrel-releasing IUD. Patients were randomly assigned when admitted in labor to postplacental or delayed IUD insertion. The women followed up in person at 6–8 weeks and 6 months and were contacted by telephone at 3 months. Women were ineligible for a study IUD postenrollment for intrapartum events including infection, hemorrhage, and cesarean delivery; these women were contacted by phone at 3 and 6 months. Expelled IUDs were replaced per patient preference. RESULTS Successful IUD placement occurred in 50 of 51 participants (98.0%) and 46 of 51 participants (90.2%) in the postplacental and delayed groups, respectively (P=.2). Expulsion within 6 months occurred in 12 of 50 (24.0%; 95% confidence interval [CI], 13.1–38.2) and two of 46 (4.4%; 95% CI 0.5–14.8) participants, respectively (P=.008). Intrauterine device use at 6 months was 43 of 51 (84.3%; 95% CI 71.4–93.0) and 39 of 51 (76.5%; 95% CI 62.5–87.2), respectively (P=.32). For ineligible patients, only 11 of 41 (26.8%) women were using IUDs at 6 months and two (4.9%) had become pregnant. CONCLUSION Intrauterine device use 6 months after delivery is similar in women who have postpartum or scheduled delayed IUD placement through a study after replacement of expelled IUDs. Expulsions are significantly higher with postplacental compared with delayed IUD placement. Women asked to follow up with their own health care providers for delayed insertion are significantly less likely to receive an IUD. CLINICALTRIALREGISTRATION ClinicalTrials.gov, www.clinicaltrials.gov, NCT00476021. LEVEL OF EVIDENCE I PMID:20966692

Physician access to drug profiles to reduce adverse reactions

NASA Astrophysics Data System (ADS)

Yasnoff, William A.; Tomkins, Edward L.; Dunn, Louise M.

1995-10-01

Adverse drug reactions (ADRs) are a major source of preventable morbidity and mortality, especially among the elderly, who use more drugs and are more sensitive to them. The insurance industry has recently addressed this problem through the implementation of drug interaction alerts to pharmacists in conjunction with immediate online claims adjudication for almost 60% of prescriptions (expected to reach 90% within 5 years). These alerts are based on stored patient drug profiles maintained by pharmacy benefit managers (PBMs) which are updated whenever prescriptions are filled. While these alerts are very helpful, the pharmacist does not prescribe, resulting in time-consuming and costly delays to contact the physician and remedy potential interactions. We have developed and demonstrated the feasibility of the PINPOINT (Pharmaceutical Information Network for prevention of interactions) system for making the drug profile and interaction information easily available to the physician before the prescription is written. We plan to test the cost-effectiveness of the system in a prospective controlled clinical trial.

Hyperconnectivity of local neocortical microcircuitry induced by prenatal exposure to valproic acid.

PubMed

Rinaldi, Tania; Silberberg, Gilad; Markram, Henry

2008-04-01

Exposure to valproic acid (VPA) during embryogenesis can cause several teratogenic effects, including developmental delays and in particular autism in humans if exposure occurs during the third week of gestation. We examined the postnatal effects of embryonic exposure to VPA on microcircuit properties of juvenile rat neocortex using in vitro electrophysiology. We found that a single prenatal injection of VPA on embryonic day 11.5 causes a significant enhancement of the local recurrent connectivity formed by neocortical pyramidal neurons. The study of the biophysical properties of these connections revealed weaker excitatory synaptic responses. A marked decrease of the intrinsic excitability of pyramidal neurons was also observed. Furthermore, we demonstrate a diminished number of putative synaptic contacts in connection between layer 5 pyramidal neurons. Local hyperconnectivity may render cortical modules more sensitive to stimulation and once activated, more autonomous, isolated, and more difficult to command. This could underlie some of the core symptoms observed in humans prenatally exposed to valproic acid.

Keratinocyte Motility Is Affected by UVA Radiation-A Comparison between Normal and Dysplastic Cells.

PubMed

Niculiţe, Cristina M; Nechifor, Marina T; Urs, Andreea O; Olariu, Laura; Ceafalan, Laura C; Leabu, Mircea

2018-06-07

UVA radiation induces multiple and complex changes in the skin, affecting epidermal cell behavior. This study reports the effects of UVA exposure on normal (HaCaT) and dysplastic (DOK) keratinocytes. The adherence, spreading and proliferation were investigated by time-lapse measurement of cell layer impedance on different matrix proteins. Prior to UVA exposure, the time required for adherence and spreading did not differ significantly for HaCaT and DOK cells, while spreading areas were larger for HaCaT cells. Under UVA exposure, HaCaT and DOK cells behavior differed in terms of movement and proliferation. The cells' ability to cover the denuded surface and individual cell trajectories were recorded by time-lapse videomicroscopy, during wound healing experiments. Dysplastic keratinocytes showed more sensitivity to UVA, exhibiting transient deficiencies in directionality of movement and a delay in re-coating the denuded area. The actin cytoskeleton displayed a cortical organization immediately after irradiation, in both cell lines, similar to mock-irradiated cells. Post-irradiation, DOK cells displayed a better organization of stress fibers, persistent filopodia, and new, stronger focal contacts. In conclusion, after UVA exposure HaCaT and DOK cells showed a different behavior in terms of adherence, spreading, motility, proliferation, and actin cytoskeleton dynamics, with the dyplastic keratinocytes being more sensitive.

Fragrance allergy: assessing the safety of washed fabrics.

PubMed

Basketter, David A; Pons-Guiraud, Annick; van Asten, Arian; Laverdet, Catherine; Marty, Jean-Paul; Martin, Ludovic; Berthod, Daniel; Siest, Sylvie; Giordano-Labadie, Françoise; Tennstedt, Dominique; Baeck, Marie; Vigan, Martine; Lainé, Gérard; Le Coz, Christophe J; Jacobs, Marie-Claude; Bayrou, Olivier; Germaux, Marie-Anne

2010-06-01

Previously, a quantitative risk assessment suggested there was no risk of induction of fragrance allergy from minor residues of fragrance chemicals on washed fabrics. To investigate whether there was any risk of the elicitation of contact allergy from fragrance chemical residues on fabric in individuals who were already sensitized. Thirty-six subjects with a positive patch test to isoeugenol (n = 19) or hydroxyisohexyl 3-cyclohexene carboxaldehyde (n = 17) were recruited. Dose-response and fabric patch tests were performed, respectively, with filter paper and a cotton sample loaded with fragrance in ethanol-diethylphthalate (DEP) and applied in a Finn Chamber or a Hill Top Chamber. Only two subjects reacted to an isoeugenol patch test concentration of 0.01% (>20x the estimated likely skin exposure level), none reacted to lower concentrations. Of 36 subjects, 18 reacted to the fabric patch treated with ethanol-DEP vehicle alone and 20 to the fragrance-chemical-treated fabric patch. These were only minor non-specific skin reactions. They were also quite evenly distributed between the two fragrance chemical allergic groups. On the basis of the examples studied, fragrance chemical residues present on fabric do not appear to present a risk of the elicitation of immediate or delayed allergic skin reactions on individuals already sensitized.

A Cross-Layer Optimized Opportunistic Routing Scheme for Loss-and-Delay Sensitive WSNs

PubMed Central

Xu, Xin; Yuan, Minjiao; Liu, Xiao; Cai, Zhiping; Wang, Tian

2018-01-01

In wireless sensor networks (WSNs), communication links are typically error-prone and unreliable, so providing reliable and timely data routing for loss- and delay-sensitive applications in WSNs it is a challenge issue. Additionally, with specific thresholds in practical applications, the loss and delay sensitivity implies requirements for high reliability and low delay. Opportunistic Routing (OR) has been well studied in WSNs to improve reliability for error-prone and unreliable wireless communication links where the transmission power is assumed to be identical in the whole network. In this paper, a Cross-layer Optimized Opportunistic Routing (COOR) scheme is proposed to improve the communication link reliability and reduce delay for loss-and-delay sensitive WSNs. The main contribution of the COOR scheme is making full use of the remaining energy in networks to increase the transmission power of most nodes, which will provide a higher communication reliability or further transmission distance. Two optimization strategies referred to as COOR(R) and COOR(P) of the COOR scheme are proposed to improve network performance. In the case of increasing the transmission power, the COOR(R) strategy chooses a node that has a higher communication reliability with same distance in comparison to the traditional opportunistic routing when selecting the next hop candidate node. Since the reliability of data transmission is improved, the delay of the data reaching the sink is reduced by shortening the time of communication between candidate nodes. On the other hand, the COOR(P) strategy prefers a node that has the same communication reliability with longer distance. As a result, network performance can be improved for the following reasons: (a) the delay is reduced as fewer hops are needed while the packet reaches the sink in longer transmission distance circumstances; (b) the reliability can be improved since it is the product of the reliability of every hop of the routing path, and the count is reduced while the reliability of each hop is the same as the traditional method. After analyzing the energy consumption of the network in detail, the value of optimized transmission power in different areas is given. On the basis of a large number of experimental and theoretical analyses, the results show that the COOR scheme will increase communication reliability by 36.62–87.77%, decrease delay by 21.09–52.48%, and balance the energy consumption of 86.97% of the nodes in the WSNs. PMID:29751589

A Cross-Layer Optimized Opportunistic Routing Scheme for Loss-and-Delay Sensitive WSNs.

PubMed

Xu, Xin; Yuan, Minjiao; Liu, Xiao; Liu, Anfeng; Xiong, Neal N; Cai, Zhiping; Wang, Tian

2018-05-03

In wireless sensor networks (WSNs), communication links are typically error-prone and unreliable, so providing reliable and timely data routing for loss- and delay-sensitive applications in WSNs it is a challenge issue. Additionally, with specific thresholds in practical applications, the loss and delay sensitivity implies requirements for high reliability and low delay. Opportunistic Routing (OR) has been well studied in WSNs to improve reliability for error-prone and unreliable wireless communication links where the transmission power is assumed to be identical in the whole network. In this paper, a Cross-layer Optimized Opportunistic Routing (COOR) scheme is proposed to improve the communication link reliability and reduce delay for loss-and-delay sensitive WSNs. The main contribution of the COOR scheme is making full use of the remaining energy in networks to increase the transmission power of most nodes, which will provide a higher communication reliability or further transmission distance. Two optimization strategies referred to as COOR(R) and COOR(P) of the COOR scheme are proposed to improve network performance. In the case of increasing the transmission power, the COOR(R) strategy chooses a node that has a higher communication reliability with same distance in comparison to the traditional opportunistic routing when selecting the next hop candidate node. Since the reliability of data transmission is improved, the delay of the data reaching the sink is reduced by shortening the time of communication between candidate nodes. On the other hand, the COOR(P) strategy prefers a node that has the same communication reliability with longer distance. As a result, network performance can be improved for the following reasons: (a) the delay is reduced as fewer hops are needed while the packet reaches the sink in longer transmission distance circumstances; (b) the reliability can be improved since it is the product of the reliability of every hop of the routing path, and the count is reduced while the reliability of each hop is the same as the traditional method. After analyzing the energy consumption of the network in detail, the value of optimized transmission power in different areas is given. On the basis of a large number of experimental and theoretical analyses, the results show that the COOR scheme will increase communication reliability by 36.62⁻87.77%, decrease delay by 21.09⁻52.48%, and balance the energy consumption of 86.97% of the nodes in the WSNs.

Skin sensitization quantitative risk assessment for occupational exposure of hairdressers to hair dye ingredients.

PubMed

Goebel, Carsten; Diepgen, Thomas L; Blömeke, Brunhilde; Gaspari, Anthony A; Schnuch, Axel; Fuchs, Anne; Schlotmann, Kordula; Krasteva, Maya; Kimber, Ian

2018-06-01

Occupational exposure of hairdressers to hair dyes has been associated with the development of allergic contact dermatitis (ACD) involving the hands. p-Phenylenediamine (PPD) and toluene-2,5-diamine (PTD) have been implicated as important occupational contact allergens. To conduct a quantitative risk assessment for the induction of contact sensitization to hair dyes in hairdressers, available data from hand rinsing studies following typical occupational exposure conditions to PPD, PTD and resorcinol were assessed. By accounting for wet work, uneven exposure and inter-individual variability for professionals, daily hand exposure concentrations were derived. Secondly, daily hand exposure was compared with the sensitization induction potency of the individual hair dye defined as the No Expected Sensitization Induction Levels (NESIL). For PPD and PTD hairdresser hand exposure levels were 2.7 and 5.9 fold below the individual NESIL. In contrast, hand exposure to resorcinol was 50 fold below the NESIL. Correspondingly, the risk assessment for PPD and PTD indicates that contact sensitization may occur, when skin protection and skin care are not rigorously applied. We conclude that awareness of health risks associated with occupational exposure to hair dyes, and of the importance of adequate protective measures, should be emphasized more fully during hairdresser education and training. Copyright © 2018 Elsevier Inc. All rights reserved.

Exploring pH-Sensitive Hydrogels Using an Ionic Soft Contact Lens: An Activity Using Common Household Materials

ERIC Educational Resources Information Center

Chen, Yueh-Huey; He, Yu-Chi; Yaung, Jing-Fun

2014-01-01

Hydrogels of the so-called smart polymers or environment-sensitive polymers are important modern biomaterials. Herein, we describe a hands-on activity to explore the pH-responsive characteristics of hydrogels using a commercially available ionic soft contact lens that is a hydrogel of poly(2-hydroxyethyl methacrylate-"co"-methacrylic…

The potential pathogenicity of chlorhexidine-sensitive Acanthamoeba strains isolated from contact lens cases from asymptomatic individuals in Tenerife, Canary Islands, Spain.

PubMed

Martín-Navarro, Carmen M; Lorenzo-Morales, Jacob; Cabrera-Serra, M Gabriela; Rancel, Fernando; Coronado-Alvarez, Nieves M; Piñero, José E; Valladares, Basilio

2008-11-01

Pathogenic strains of the genus Acanthamoeba are causative agents of a serious sight-threatening infection of the eye known as Acanthamoeba keratitis. The prevalence of this infection has risen in the past 20 years, mainly due to the increase in number of contact lens wearers. In this study, the prevalence of Acanthamoeba in a risk group constituted by asymptomatic contact lens wearers from Tenerife, Canary Islands, Spain, was evaluated. Contact lenses and contact lens cases were analysed for the presence of Acanthamoeba isolates. The isolates' genotypes were also determined after rDNA sequencing. The pathogenic potential of the isolated strains was subsequently established using previously described molecular and biochemical assays, which allowed the selection of three strains with high pathogenic potential. Furthermore, the sensitivity of these isolates against two standard drugs, ciprofloxacin and chlorhexidine, was analysed. As the three selected strains were sensitive to chlorhexidine, its activity and IC(50) were evaluated. Chlorhexidine was found to be active against these strains and the obtained IC(50) values were compared to the concentrations of this drug present in contact lens maintenance solutions. It was observed that the measured IC(50) was higher than the concentration found in these maintenance solutions. Therefore, the ineffectiveness of chlorhexidine-containing contact lens maintenance solutions against potentially pathogenic strains of Acanthamoeba is demonstrated in this study.

Advances in reduction techniques for tire contact problems

NASA Technical Reports Server (NTRS)

Noor, Ahmed K.

1995-01-01

Some recent developments in reduction techniques, as applied to predicting the tire contact response and evaluating the sensitivity coefficients of the different response quantities, are reviewed. The sensitivity coefficients measure the sensitivity of the contact response to variations in the geometric and material parameters of the tire. The tire is modeled using a two-dimensional laminated anisotropic shell theory with the effects of variation in geometric and material parameters, transverse shear deformation, and geometric nonlinearities included. The contact conditions are incorporated into the formulation by using a perturbed Lagrangian approach with the fundamental unknowns consisting of the stress resultants, the generalized displacements, and the Lagrange multipliers associated with the contact conditions. The elemental arrays are obtained by using a modified two-field, mixed variational principle. For the application of reduction techniques, the tire finite element model is partitioned into two regions. The first region consists of the nodes that are likely to come in contact with the pavement, and the second region includes all the remaining nodes. The reduction technique is used to significantly reduce the degrees of freedom in the second region. The effectiveness of the computational procedure is demonstrated by a numerical example of the frictionless contact response of the space shuttle nose-gear tire, inflated and pressed against a rigid flat surface. Also, the research topics which have high potential for enhancing the effectiveness of reduction techniques are outlined.

Enhanced sensitization and elicitation responses caused by mixtures of common fragrance allergens.

PubMed

Bonefeld, Charlotte Menné; Nielsen, Morten Milek; Rubin, Ingrid Maria Cecilia; Vennegaard, Marie Torp; Dabelsteen, Sally; Gimenéz-Arnau, Elena; Lepoittevin, Jean-Pierre; Geisler, Carsten; Johansen, Jeanne Duus

2011-12-01

Perfumes are complex mixtures composed of many fragrance ingredients, many of which are known to be only weak allergens when tested individually. It is therefore surprising that fragrance contact allergy is one of the most common forms of contact allergy. To investigate whether mixing different fragrance allergens leads to increased sensitization potency, and to examine the difference in the challenge response to one chemical in mice sensitized either with the mixture of allergens or with only the relevant allergen. CBA mice were sensitized with three different concentrations of three fragrance allergens alone or as a mixture. The sensitization and elicitation responses were measured by ear thickness plus infiltration of B and T cells and T cell proliferation in the draining lymph nodes. We found a dose-dependent sensitization response for each of the allergens. An increased response was seen when the allergens were mixed. A stronger challenge response to cinnamal was seen in mice sensitized with the allergen mixture than in mice sensitized with cinnamal alone. Our findings suggest that mixtures of allergens increase the primary response that potentiates the generation of memory T cells in response to the specific allergen. Thus, allergen mixtures enhance both induction and elicitation of contact allergy. © 2011 John Wiley & Sons A/S.

Comparison of the success rate between self-drilling and self-tapping miniscrews: a systematic review and meta-analysis.

PubMed

Yi, Jianru; Ge, Mengke; Li, Meile; Li, Chunjie; Li, Yu; Li, Xiaobing; Zhao, Zhihe

2017-06-01

Both the self-drilling and self-tapping miniscrews have been commonly used as anchorage reinforcement devices in orthodontic treatment. The aim of this study was to compare the success rates of self-drilling and self-tapping miniscrews in orthodontic practice. Literature searches were performed by electronic search in database including PubMed, Embase, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure and SIGLE, and manual search of relevant journals and reference lists of included studies. Randomized controlled trials, clinical controlled trials and cohort studies comparing the success rates of self-drilling and self-tapping miniscrews as orthodontic anchorage. The data of success rates and root contact rates were extracted by two investigators independently. After evaluating the risk of bias, the odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Subgroup analysis was performed on the basis of study design, follow-ups, participant ages and immediate/delayed loading. Sensitivity analysis was performed to test the stability of the results in meta-analysis. Six studies assessed as high quality were included in the meta-analysis. The meta-analysis results showed no difference between the two types of screws in the success rates. The root contact rates of the two screws were similar, while self-drilling miniscrews displayed higher risk of failure when contacting with a tooth root. Currently available clinical evidence suggests that the success rates of self-tapping and self-drilling miniscrews are similar. Determination of the position and direction of placement should be more precise when self-drilling miniscrews are used in sites with narrow root proximity. None. None. © The Author 2016. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com

Early Sensitivity to Discourse-Level Anomalies: Evidence from Self-Paced Reading

ERIC Educational Resources Information Center

Stewart, Andrew J.; Kidd, Evan; Haigh, Matthew

2009-01-01

Two word-by-word, self-paced reading experiments investigated the speed with which readers were sensitive to discourse-level anomalies. An account arguing for delayed sensitivity (Guzman & Klin, 2000) was contrasted with one allowing for rapid sensitivity (Myers & O'Brien, 1998). Anomalies related to spatial information (Experiment 1) and…

Adolescent Methylmercury Exposure Affects Choice and Delay Discounting in Mice

PubMed Central

Boomhower, Steven R.; Newland, M. Christopher

2016-01-01

The developing fetus is vulnerable to low-level exposure to methylmercury (MeHg), an environmental neurotoxicant, but the consequences of exposure during the adolescent period remain virtually unknown. The current experiments were designed to assess the effects of low-level MeHg exposure during adolescence on delay discounting, preference for small, immediate reinforcers over large, delayed ones, using a mouse model. Thirty-six male C57BL/6n mice were exposed to 0, 0.3, or 3.0 ppm mercury (as MeHg) via drinking water from postnatal day 21 through 59, encompassing the murine adolescent period. As adults, mice lever-pressed for a 0.01-cc droplet of milk solution delivered immediately or four 0.01-cc droplets delivered after a delay. Delays ranged from 1.26 to 70.79 seconds, all presented within a session. A model based on the Generalized Matching Law indicated that sensitivity to reinforcer magnitude was lower for MeHg-exposed mice relative to controls; responding in MeHg-exposed mice was relatively indifferent to the larger reinforcer. Sensitivity to reinforcer delay was reduced (delay discounting was decreased) in the 0.3-ppm group, but not in the 3.0-ppm group, compared to controls. Adolescence is a developmental period during which the brain and behavior may be vulnerable to MeHg exposure. As with gestational exposure, the effects are reflected in the impact of reinforcing stimuli. PMID:27677934

Forming Human-Robot Teams Across Time and Space

NASA Technical Reports Server (NTRS)

Hambuchen, Kimberly; Burridge, Robert R.; Ambrose, Robert O.; Bluethmann, William J.; Diftler, Myron A.; Radford, Nicolaus A.

2012-01-01

NASA pushes telerobotics to distances that span the Solar System. At this scale, time of flight for communication is limited by the speed of light, inducing long time delays, narrow bandwidth and the real risk of data disruption. NASA also supports missions where humans are in direct contact with robots during extravehicular activity (EVA), giving a range of zero to hundreds of millions of miles for NASA s definition of "tele". . Another temporal variable is mission phasing. NASA missions are now being considered that combine early robotic phases with later human arrival, then transition back to robot only operations. Robots can preposition, scout, sample or construct in advance of human teammates, transition to assistant roles when the crew are present, and then become care-takers when the crew returns to Earth. This paper will describe advances in robot safety and command interaction approaches developed to form effective human-robot teams, overcoming challenges of time delay and adapting as the team transitions from robot only to robots and crew. The work is predicated on the idea that when robots are alone in space, they are still part of a human-robot team acting as surrogates for people back on Earth or in other distant locations. Software, interaction modes and control methods will be described that can operate robots in all these conditions. A novel control mode for operating robots across time delay was developed using a graphical simulation on the human side of the communication, allowing a remote supervisor to drive and command a robot in simulation with no time delay, then monitor progress of the actual robot as data returns from the round trip to and from the robot. Since the robot must be responsible for safety out to at least the round trip time period, the authors developed a multi layer safety system able to detect and protect the robot and people in its workspace. This safety system is also running when humans are in direct contact with the robot, so it involves both internal fault detection as well as force sensing for unintended external contacts. The designs for the supervisory command mode and the redundant safety system will be described. Specific implementations were developed and test results will be reported. Experiments were conducted using terrestrial analogs for deep space missions, where time delays were artificially added to emulate the longer distances found in space.

Effect of Tabor parameter on hysteresis losses during adhesive contact

NASA Astrophysics Data System (ADS)

Ciavarella, M.; Greenwood, J. A.; Barber, J. R.

2017-01-01

The Tabor parameter μ is conventionally assumed to determine the range of applicability of the classical 'JKR' solution for adhesive elastic contact of a sphere and a plane, with the variation of the contact area and approach with load, and in particular the maximum tensile force (the pull-off force) being well predicted for μ > 5 . Here we show that the hysteretic energy loss during a contact separation cycle is significantly overestimated by the JKR theory, even at quite large values of μ. This stems from the absence of long-range tensile forces in the JKR theory, which implies that jump into contact is delayed until the separation α = 0 . We develop an approximate solution based on the use of Wu's solution with van der Waals interactions for jump-in, and the JKR theory for jump out of contact, and show that for μ > 5 , the predicted hysteresis loss is then close to that found by direct numerical solutions using the Lennard-Jones force law. We also show how the same method can be adapted to allow for contact between bodies with finite support stiffness.

Clinical efficacy of dim light melatonin onset testing in diagnosing delayed sleep phase syndrome.

PubMed

Rahman, Shadab A; Kayumov, Leonid; Tchmoutina, Ekaterina A; Shapiro, Colin M

2009-05-01

Delayed Sleep Phase Syndrome (DSPS) arises from biological clock desynchrony and accounts for 10% of chronic insomnia patients. Currently DSPS is diagnosed based on sleep/wake cycle disruptions rather than examining the underlying biological clock alterations. The objective of the study was to determine the sensitivity and specificity of the Dim Light Melatonin Onset (DLMO) Test in diagnosing DSPS in a clinical setting. Fifty-six patients (mean age 28 years) symptomatic of DSPS participated in the study. Following an initial assessment of DSPS using sleep diaries, participants underwent two consecutive nights of polysomnography (PSG), with an imposed sleep period on the second night to demonstrate the delay in the timing of habitual sleep period and to thereby confirm DSPS. Circadian phase delays were also measured using melatonin secretion profiles, and the efficacy of diagnosing DSPS using DLMO was compared to using sleep diaries and PSG. Melatonin secretion was assayed for each individual by ELISA using saliva samples. Main outcome measures included the time of melatonin secretion onset, clinical sensitivity and specificity of the DLMO test. The time of melatonin secretion onset was significantly delayed in DSPS patients. Clinical sensitivity and specificity of the DLMO test in diagnosing DSPS were 90.3% and 84.0%, respectively. The DLMO test is an accurate tool for differentiating between sleep disorder patients with or without underlying circadian rhythm disruption. It is effective for phase typing DSPS patients in a clinical setting.

[Current contact allergens].

PubMed

Geier, J; Uter, W; Lessmann, H; Schnuch, A

2011-10-01

Ever-changing exposure to contact allergens, partly due to statutory directives (e.g. nickel, chromate, methyldibromo glutaronitrile) or recommendations from industrial associations (e.g. hydroxyisohexyl 3-cyclohexene carboxaldehyde), requires on-going epidemiologic surveillance of contact allergy. In this paper, the current state with special focus in fragrances and preservatives is described on the basis of data of the Information Network of Departments of Dermatology (IVDK) of the year 2010. In 2010, 12,574 patients were patch tested in the dermatology departments belonging to the IVDK. Nickel is still the most frequent contact allergen. However the continuously improved EU nickel directive already has some beneficial effect; sensitization frequency in young women is dropping. In Germany, chromate-reduced cement has been in use now for several years, leading to a decline in chromate sensitization in brick-layers. Two fragrance mixes are part of the German baseline series; they are still relevant. The most important fragrances in these mixes still are oak moss absolute and hydroxyisohexyl 3-cyclohexene carboxaldehyde. However, in relation to these leading allergens, sensitization frequency to other fragrances contained in the mixes seems to be increasing. Among the preservatives, MCI/MI has not lost its importance as contact allergen, in contrast to MDBGN. Sources of MCI/MI sensitization obviously are increasingly found in occupational context. Methylisothiazolinone is a significant allergen in occupational settings, and less frequently in body care products.

A novel adaptive, real-time algorithm to detect gait events from wearable sensors.

PubMed

Chia Bejarano, Noelia; Ambrosini, Emilia; Pedrocchi, Alessandra; Ferrigno, Giancarlo; Monticone, Marco; Ferrante, Simona

2015-05-01

A real-time, adaptive algorithm based on two inertial and magnetic sensors placed on the shanks was developed for gait-event detection. For each leg, the algorithm detected the Initial Contact (IC), as the minimum of the flexion/extension angle, and the End Contact (EC) and the Mid-Swing (MS), as minimum and maximum of the angular velocity, respectively. The algorithm consisted of calibration, real-time detection, and step-by-step update. Data collected from 22 healthy subjects (21 to 85 years) walking at three self-selected speeds were used to validate the algorithm against the GaitRite system. Comparable levels of accuracy and significantly lower detection delays were achieved with respect to other published methods. The algorithm robustness was tested on ten healthy subjects performing sudden speed changes and on ten stroke subjects (43 to 89 years). For healthy subjects, F1-scores of 1 and mean detection delays lower than 14 ms were obtained. For stroke subjects, F1-scores of 0.998 and 0.944 were obtained for IC and EC, respectively, with mean detection delays always below 31 ms. The algorithm accurately detected gait events in real time from a heterogeneous dataset of gait patterns and paves the way for the design of closed-loop controllers for customized gait trainings and/or assistive devices.

Maternal Sensitivity Predicts Fewer Sleep Problems at Early Adolescence for Toddlers with Negative Emotionality: A Case of Differential Susceptibility.

PubMed

Conway, Anne; Modrek, Anahid; Gorroochurn, Prakash

2018-02-01

Theory underscores the importance of parenting in sleep development, but few studies have examined whether links vary by temperament. To address this gap, we tested whether potential links between early maternal sensitivity and early adolescent sleep problems varied by child negative emotionality and delay of gratification. Using data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (N = 820), we found that high maternal sensitivity predicted fewer bedtime problems and longer sleep duration at 6th grade for toddlers with high negative emotionality, whereas low maternal sensitivity predicted the reverse. No differences were observed for low negative emotionality. Moreover, delay of gratification predicted fewer bedtime problems at 6th grade, but did not moderate associations between maternal sensitivity, negative emotionality, and sleep. Findings demonstrate that high, but not low, negative emotionality renders toddlers differentially susceptible and receptive to maternal sensitivity in relation to sleep.

Determinants of Motion Sickness in Tilting Trains: Coriolis/Cross-Coupling Stimuli and Tilt Delay

PubMed Central

Bertolini, Giovanni; Durmaz, Meek Angela; Ferrari, Kim; Küffer, Alexander; Lambert, Charlotte; Straumann, Dominik

2017-01-01

Faster trains require tilting of the cars to counterbalance the centrifugal forces during curves. Motion sensitive passengers, however, complain of discomfort and overt motion sickness. A recent study comparing different control systems in a tilting train, suggested that the delay of car tilts relative to the curve of the track contributes to motion sickness. Other aspects of the motion stimuli, like the lateral accelerations and the car jitters, differed between the tested conditions and prevented a final conclusion on the role of tilt delay. Nineteen subjects were tested on a motorized 3D turntable that simulated the roll tilts during yaw rotations experienced on a tilting train, isolating them from other motion components. Each session was composed of two consecutive series of 12 ideal curves that were defined on the bases of recordings during an actual train ride. The simulated car tilts started either at the beginning of the curve acceleration phase (no-delay condition) or with 3 s of delay (delay condition). Motion sickness was self-assessed by each subject at the end of each series using an analog motion sickness scale. All subjects were tested in both conditions. Significant increases of motion sickness occurred after the first sequence of 12 curves in the delay condition, but not in the no-delay condition. This increase correlated with the sensitivity of motion sickness, which was self-assessed by each subject before the experiment. The second sequence of curve did not lead to a significant further increase of motion sickness in any condition. Our results demonstrate that, even if the speed and amplitude are as low as those experienced on tilting trains, a series of roll tilts with a delay relative to the horizontal rotations, isolated from other motion stimuli occurring during a travel, generate Coriolis/cross-coupling stimulations sufficient to rapidly induce motion sickness in sensitive individuals. The strength and the rapid onset of the motion sickness reported confirm that, even if the angular velocity involved are low, the Coriolis/cross-coupling resulting from the delay is a major factor in causing sickness that can be resolved by improving the tilt timing relative to the horizontal rotation originating from the curve. PMID:28555125

Body piercing and metal allergic contact sensitivity: North American contact dermatitis group data from 2007 to 2010.

PubMed

Warshaw, Erin M; Kingsley-Loso, Jaime L; DeKoven, Joel G; Belsito, Donald V; Zug, Kathryn A; Zirwas, Matthew J; Maibach, Howard I; Taylor, James S; Sasseville, Denis; Fowler, Joseph F; Mathias, Charles Gordon Toby; DeLeo, Vincent A; Pratt, Melanie D; Marks, James G; Fransway, Anthony F

2014-01-01

This study aimed to examine the association between piercing and patch test sensitivity to metals (nickel, cobalt, and chromium) in North America. A retrospective analysis of 9334 patients tested by the North American Contact Dermatitis Group from 2007 to 2010 was conducted. Nickel sensitivity was statistically associated with at least 1 piercing (risk ratio [RR], 2.52; 95% confidence interval [CI], 2.26-2.81; P < 0.0001) and nickel sensitivity rates increased with the number of piercings (16% for 1 piercing to 32% for ≥ 5 piercings). Prevalence of nickel sensitivity was higher in females (23.2%) than in males (7.1%), but the association with piercing was stronger in males (RR, 2.38; 95% CI, 1.72-3.30; P < 0.0001) than in females (RR, 1.30; CI, 1.13-1.49; P = 0.0002). Crude analysis indicated that cobalt sensitivity was statistically associated with piercing (RR, 1.63; 95% CI, 1.40-1.91; P < 0.0001); however, stratified analysis showed that this relationship was confounded by nickel. After adjusting for nickel sensitivity, the adjusted risk ratio for piercing and cobalt was 0.78 (not significant). Chromium sensitivity was negatively associated with piercing (RR, 0.60; 95% CI, 0.48-0.75; P < 0.0001). Piercing was statistically associated with sensitivity to nickel. This relationship was dose dependent and stronger in males. Cobalt sensitivity was not associated with piercing when adjusted for nickel. Chromium sensitivity was negatively associated with piercing.

Development and validation of a parent-report measure for detection of cognitive delay in infancy.

PubMed

Schafer, Graham; Genesoni, Lucia; Boden, Greg; Doll, Helen; Jones, Rosamond A K; Gray, Ron; Adams, Eleri; Jefferson, Ros

2014-12-01

To develop a brief, parent-completed instrument (ERIC - Early Report by Infant Caregivers) for detection of cognitive delay in 10- to 24-month-olds born preterm, or of low birthweight, or with perinatal complications, and to establish ERIC's diagnostic properties. Scores for ERIC were collected from the parents of 317 children meeting ≥inclusion criterion (birthweight <1500 g, gestational age <34 completed weeks, 5 min Apgar score <7, or presence of hypoxic-ischaemic encephalopathy) and no exclusion criteria. Children were assessed using a criterion score of below 80 on the Bayley Scales of Infant and Toddler Development-III cognitive scale. Items were retained according to their individual associations with delay. Sensitivity, specificity, and positive and negative predictive values were estimated and a truncated ERIC was developed for use in children <14 months old. ERIC correctly detected developmental delay in 17 out of 18 children in the sample, with 94.4% sensitivity, 76.9% specificity, 19.8% positive predictive value, 99.6% negative predictive value, 4.09 likelihood ratio positive, and 0.07 likelihood ratio negative. ERIC has potential value as a quickly administered diagnostic instrument for the absence of early cognitive delay in 10- to 24-month-old preterm infants and as a screen for cognitive delay. © 2014 Mac Keith Press.

The procrastinators want it now: Behavioral and event-related potential evidence of the procrastination of intertemporal choices.

PubMed

Wu, Haiyan; Gui, Danyang; Lin, Wenzheng; Gu, Ruolei; Zhu, Xiangru; Liu, Xun

2016-08-01

Much past research has focused on the correlation between procrastination and personality traits (e.g., impulsivity). According to the temporal motivation theory, procrastinators are impulsive and sensitive to delays in time. However, there is still a lack of direct evidence of the tendency of procrastinators to prefer immediate over future rewards. To investigate this question, we recorded event-related potentials (ERPs) in the brain while participants performed an intertemporal choice task involving both time delay and reward processing. The participants were assigned to a high procrastination group and a low procrastination group according to their scores on self-report measures. We found that high procrastination participants preferred immediate rewards compared to future ones whereas low procrastination participants did not. High procrastinators also exhibited a larger and delayed P2 component, indicating delay time processing and abnormal reward processing. No significant effect associated with procrastination was found on the P300 component. Taken together, these findings suggest that high procrastinators are more impulsive and encode the information of delay time more slowly but with a higher level of motivation-driven attention. The current study substantiates higher impulsivity in procrastination and verifies that a difference exists in the sensitivity to time delay between high and low procrastinators. Copyright © 2016 Elsevier Inc. All rights reserved.

Individual Differences in Discount Rate Are Associated With Demand for Self-Administered Cocaine, But Not Sucrose

PubMed Central

Koffarnus, Mikhail N.; Woods, James H.

2011-01-01

Substance abusers, including cocaine abusers, discount delayed rewards to a greater extent than do matched controls. In the current experiment, individual differences in discounting of delayed rewards in rats (choice of one immediate over three delayed sucrose pellets) were assessed for associations with demand for either sucrose pellets or an i.v. dose of 0.1 mg/kg/infusion cocaine. Twenty-four male Sprague Dawley rats were split into three groups based on sensitivity to delay to reinforcement. Then, demand for sucrose pellets and cocaine was determined across a range of fixed-ratio (FR) values. Delay discounting was then reassessed to determine the stability of this measure over the course of the experiment. Individual differences in impulsive choice were positively associated with elasticity of demand for cocaine, a measure of reinforcer value, indicating that rats having higher discount rates also valued cocaine more. Impulsive choice was not associated with level of cocaine consumption as price approached 0, or any parameter associated with demand for sucrose. Individual sensitivity to delay was correlated with the initial assessment when reassessed at the end of the experiment, although impulsive choice increased for this cohort of rats as a whole. These findings suggest that impulsive choice in rats is positively associated with valuation of cocaine, but not sucrose. PMID:21812874

Immunotherapy of allergic contact dermatitis.

PubMed

Spiewak, Radoslaw

2011-08-01

The term 'immunotherapy' refers to treating diseases by inducing, enhancing or suppressing immune responses. As allergy is an excessive, detrimental immune reaction to otherwise harmless environmental substances, immunotherapy of allergic disease is aimed at the induction of tolerance toward sensitizing antigens. This article focuses on the historical developments, present state and future outlook for immunotherapy with haptens as a therapeutic modality for allergic contact dermatitis. Inspired by the effectiveness of immunotherapy in respiratory allergies, attempts were undertaken at curing allergic contact dermatitis by means of controlled administration of the sensitizing haptens. Animal and human experiments confirmed that tolerance to haptens can be induced most effectively when the induction of tolerance precedes attempted sensitization. In real life, however, therapy is sought by people who are already sensitized and an effective reversal of hypersensitivity seems more difficult to achieve. Decades of research on Rhus hypersensitivity led to a conclusion that immunotherapy can suppress Rhus dermatitis, however, only to a limited degree, for a short period of time, and at a high risk of side effects, which makes this method therapeutically unprofitable. Methodological problems with most available studies of immunotherapy of contact allergy to nickel make any definite conclusions impossible at this stage.

Bioactivation of cinnamic alcohol forms several strong skin sensitizers.

PubMed

Niklasson, Ida B; Ponting, David J; Luthman, Kristina; Karlberg, Ann-Therese

2014-04-21

Cinnamic alcohol is a frequent contact allergen, causing allergic contact dermatitis (ACD) in a substantial number of individuals sensitized from contacts with fragrances. Hence, cinnamic alcohol is one of the constituents in fragrance mix I (FM I) used for screening contact allergy in dermatitis patients. Cinnamic alcohol lacks structural alerts for protein reactivity and must therefore be activated by either air oxidation or bioactivation to be able to act as a sensitizer. In the present study, we explored the bioactivation of cinnamic alcohol using human liver microsomes (HLM), and the potential pathways for these reactions were modeled by in silico (DFT) techniques. Subsequently, the reactivity of cinnamic alcohol and its metabolites toward a model hexapeptide were investigated. In addition to cinnamic aldehyde and cinnamic acid, two highly sensitizing epoxides previously unobserved in studies of bioactivation were detected in the incubations with HLMs. Formation of epoxy cinnamic aldehyde was shown (both by the liver microsomal experiments, in which no depletion of epoxy cinnamic alcohol was observed after initial formation, and by the very high activation energy found for the oxidation thereof by calculations) to proceed via cinnamic aldehyde and not epoxy cinnamic alcohol.

[Frequency of contact sensitization to modern dressings used to treat chronic leg ulcer].

PubMed

Garval, E; Plee, J; Lesage, C; Grange-Prunier, A; Bernard, P; Perceau, G

2018-05-01

Allergic contact dermatitis around chronic leg ulcers (CLU) is a common complication in patients presenting CLU and prolongs healing times. The aim of this study was to describe the rate of sensitization to modern dressings (MD) used in these patients and to assess whether there is a relation between the number of sensitizations and ulcer type, the time from onset of the ulcer, and patient age and gender. We conducted a retrospective study at Reims University Hospital between 2010 and 2014 that included all patients with CLU of vascular etiology surrounded by eczematous lesions, and who had one of the patch-tests in the following 3 series: European baseline±leg ulcers±corticosteroids. Among the 73 patients included, 43 % were polysensitized. Thirty-three patients (45 %) were sensitized to MD (38 % to hydrocolloids, 18 % to hydrogels, 7 % to hydrocellular dressings, 7 % to hydrofiber dressings, 5 % to contact layers and 3 % to alginates). Median age and sex did not differ between "polysensitized" patients and "non-polysensitized" patients (P=0.84 and P=0.25, respectively). Polysensitization was more frequent among patients presenting ulcers for more than 5 years (P=0.032). Practically half of all patients presenting CLU with surrounding contact dermatitis had sensitization to modern dressings (mostly hydrocolloids and hydrogels). The rate of sensitization increased with the length of presence of CLU. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Enhanced external and culturally sensitive attributions after extended intercultural contact.

PubMed

Vollhardt, Johanna Ray

2010-06-01

This study examined the effect of close and extended intercultural contact on attributions for behaviour of out-group members. Specifically, it was hypothesized that extended intercultural contact would enhance the ability to make external and culturally sensitive attributions for ambiguous behaviour of out-group members, while decreasing the common tendency to overestimate internal factors. A content analysis of open-ended attributions supported these hypotheses, revealing that majority group members in Germany who had hosted an exchange student from another continent used significantly less internal and more external as well as culturally sensitive attributions to explain the behaviour described in critical intercultural incidents, compared to future hosts. The effect remained significant when controlling for perspective taking and prior intercultural experience. Moreover, the hypothesis was supported for scenarios describing different cultural groups (regardless of the exchange students' country of origin), suggesting a generalized effect. Problems of selection bias are discussed, and the importance of studying a range of positive outcomes of intercultural contact is emphasized.

Vibrational shape tracking of atomic force microscopy cantilevers for improved sensitivity and accuracy of nanomechanical measurements

NASA Astrophysics Data System (ADS)

Wagner, Ryan; Killgore, Jason P.; Tung, Ryan C.; Raman, Arvind; Hurley, Donna C.

2015-01-01

Contact resonance atomic force microscopy (CR-AFM) methods currently utilize the eigenvalues, or resonant frequencies, of an AFM cantilever in contact with a surface to quantify local mechanical properties. However, the cantilever eigenmodes, or vibrational shapes, also depend strongly on tip-sample contact stiffness. In this paper, we evaluate the potential of eigenmode measurements for improved accuracy and sensitivity of CR-AFM. We apply a recently developed, in situ laser scanning method to experimentally measure changes in cantilever eigenmodes as a function of tip-sample stiffness. Regions of maximum sensitivity for eigenvalues and eigenmodes are compared and found to occur at different values of contact stiffness. The results allow the development of practical guidelines for CR-AFM experiments, such as optimum laser spot positioning for different experimental conditions. These experiments provide insight into the complex system dynamics that can affect CR-AFM and lay a foundation for enhanced nanomechanical measurements with CR-AFM.

Delayed astrocytic contact with cerebral blood vessels in FGF-2 deficient mice does not compromise permeability properties at the developing blood-brain barrier.

PubMed

Saunders, Norman R; Dziegielewska, Katarzyna M; Unsicker, Klaus; Ek, C Joakim

2016-11-01

The brain functions within a specialized environment tightly controlled by brain barrier mechanisms. Understanding the regulation of barrier formation is important for understanding brain development and may also lead to finding new ways to deliver pharmacotherapies to the brain; access of many potentially promising drugs is severely hindered by these barrier mechanisms. The cellular composition of the neurovascular unit of the blood-brain barrier proper and their effects on regulation of its function are beginning to be understood. One hallmark of the neurovascular unit in the adult is the astroglial foot processes that tightly surround cerebral blood vessels. However their role in barrier formation is still unclear. In this study we examined barrier function in newborn, juvenile and adult mice lacking fibroblast growth factor-2 (FGF-2), which has been shown to result in altered astroglial differentiation during development. We show that during development of FGF-2 deficient mice the astroglial contacts with cerebral blood vessels are delayed compared with wild-type animals. However, this delay did not result in changes to the permeability properties of the blood brain barrier as assessed by exclusion of either small or larger sized molecules at this interface. In addition cerebral vessels were positive for tight-junction proteins and we observed no difference in the ultrastructure of the tight-junctions. The results indicate that the direct contact of astroglia processes to cerebral blood vessels is not necessary for either the formation of the tight-junctions or for basic permeability properties and function of the blood-brain barrier. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1201-1212, 2016. © 2016 Wiley Periodicals, Inc.

An Experimental Investigation of Hypergolic Ignition Delay of Hydrogen Peroxide with Fuel Mixtures

NASA Technical Reports Server (NTRS)

Blevins, John A.; Gostowski, Rudy; Chianese, Silvio

2003-01-01

An experimental investigation of hypergolicity and ignition delay of fuel mixtures with hydrogen peroxide is presented. Example results of high speed photography and schleiren from drop tests are shown. Also, a discussion of the sensitivity to experimental parameters such as drop size and subsequent uncertainty considerations of ignition delay results is presented. It is shown that using the described setup on the mixtures presented, the precision uncertainty is on the order of 6% of average ignition delay and 5% of average decomposition delay. This represents sufficient repeatability for first order discrimination of ignition delay for propellant development and screening. Two mixtures, each using commonly available amines and transition metal compounds, are presented as examples that result in ignition delays on the order of 10 milliseconds.

High pressure liquid and gaseous oxygen impact sensitivity evaluation of materials for use at Kennedy Space Center

NASA Technical Reports Server (NTRS)

Bryan, C. J.

1976-01-01

The sensitivity of materials in contact with gaseous oxygen (GOX) or liquid oxygen (LOX) was examined. Specifically, the reactivity of materials when in contact with GOX or LOX if subjected to such stimuli as mechanical impact, adiabatic compression (pneumatic impact), or an electrical discharge in the form of a spark were examined. Generally, materials are more sensitive in gaseous oxygen than in liquid oxygen and impact sensitivity is known to increase with increasing pressure. Materials presently being used or considered for use in oxygen systems at KSC were evaluated. Results are given in tabular form.

Special tinted contact lens on colour-defects.

PubMed

Mutilab, H A; Sharanjeet-Kaur; Keu, L K; Choo, P F

2012-01-01

The objective of this study was to determine the visual function of colour-deficient subjects when wearing special red tint contact lenses. A total of 17 subjects with congenital colour vision deficiency (14 deutans and 3 protans), voluntarily participated in this study. The average age for the subjects was 23.00 ± 4.06 years old. Visual functions tested were visual acuity (LogMAR), contrast sensitivity (FACT Chart) and stereopsis (TNO and Howard Dolman tests). Two types of special red tint lenses were used in this study; Type I (light red) and Type II (dark red). The protans and deutans showed no significant changes in visual acuity and contrast sensitivity when wearing either type of contact lens. Stereopsis testing using the Horward-Dolman test gave no significant changes but significant differences were seen using the TNO test. Stereopsis using the TNO test was significantly poorer with the red tinted contact lenses compared to without for both protons and deutans. Testing binocularly with Ishihara plates showed that 88% (n=15) of patients passed the test with Type I and Type II contact lenses. When D15 test was done, 3 patients (17.6%) were 'normal' when using the Type I contact lenses and 2 patients (11.8%) were 'normal' when using the Type II contact lenses. However, with FM100Hue test, most patients showed deutan responses. Total error scores (TES) were found to be higher with Type I and Type II contact lenses compared to without. The Type I and II special tinted contact lens used in this study did not cause a reduction of visual acuity and contrast sensitivity for the colour defects. Stereopsis was also not reduced with the Type I and Type II contact lenses for the colour defects except when tested with the TNO test. Colour vision defects became difficult to detect using the Ishihara plates but FM100Hue test did not show any improvement with the Type I and Type II contact lenses.

A social activity and physical contact-based routing algorithm in mobile opportunistic networks for emergency response to sudden disasters

NASA Astrophysics Data System (ADS)

Wang, Xiaoming; Lin, Yaguang; Zhang, Shanshan; Cai, Zhipeng

2017-05-01

Sudden disasters such as earthquake, flood and hurricane necessitate the employment of communication networks to carry out emergency response activities. Routing has a significant impact on the functionality, performance and flexibility of communication networks. In this article, the routing problem is studied considering the delivery ratio of messages, the overhead ratio of messages and the average delay of messages in mobile opportunistic networks (MONs) for enterprise-level emergency response communications in sudden disaster scenarios. Unlike the traditional routing methods for MONS, this article presents a new two-stage spreading and forwarding dynamic routing algorithm based on the proposed social activity degree and physical contact factor for mobile customers. A new modelling method for describing a dynamic evolving process of the topology structure of a MON is first proposed. Then a multi-copy spreading strategy based on the social activity degree of nodes and a single-copy forwarding strategy based on the physical contact factor between nodes are designed. Compared with the most relevant routing algorithms such as Epidemic, Prophet, Labelled-sim, Dlife-comm and Distribute-sim, the proposed routing algorithm can significantly increase the delivery ratio of messages, and decrease the overhead ratio and average delay of messages.

The Effect of Temporal Perception on Weight Perception

PubMed Central

Kambara, Hiroyuki; Shin, Duk; Kawase, Toshihiro; Yoshimura, Natsue; Akahane, Katsuhito; Sato, Makoto; Koike, Yasuharu

2013-01-01

A successful catch of a falling ball requires an accurate estimation of the timing for when the ball hits the hand. In a previous experiment in which participants performed ball-catching task in virtual reality environment, we accidentally found that the weight of a falling ball was perceived differently when the timing of ball load force to the hand was shifted from the timing expected from visual information. Although it is well known that spatial information of an object, such as size, can easily deceive our perception of its heaviness, the relationship between temporal information and perceived heaviness is still not clear. In this study, we investigated the effect of temporal factors on weight perception. We conducted ball-catching experiments in a virtual environment where the timing of load force exertion was shifted away from the visual contact timing (i.e., time when the ball hit the hand in the display). We found that the ball was perceived heavier when force was applied earlier than visual contact and lighter when force was applied after visual contact. We also conducted additional experiments in which participants were conditioned to one of two constant time offsets prior to testing weight perception. After performing ball-catching trials with 60 ms advanced or delayed load force exertion, participants’ subjective judgment on the simultaneity of visual contact and force exertion changed, reflecting a shift in perception of time offset. In addition, timing of catching motion initiation relative to visual contact changed, reflecting a shift in estimation of force timing. We also found that participants began to perceive the ball as lighter after conditioning to 60 ms advanced offset and heavier after the 60 ms delayed offset. These results suggest that perceived heaviness depends not on the actual time offset between force exertion and visual contact but on the subjectively perceived time offset between them and/or estimation error in force timing. PMID:23450805

Occupations at risk of developing contact allergy to isothiazolinones in Danish contact dermatitis patients: results from a Danish multicentre study (2009-2012).

PubMed

Schwensen, Jakob F; Menné, Torkil; Andersen, Klaus E; Sommerlund, Mette; Johansen, Jeanne D

2014-11-01

In recent years, the prevalence of contact allergy to isothiazolinones has reached epidemic levels. Few studies have presented data on occupations at risk of developing contact allergy to isothiazolinones. To present demographics and examine risk factors for sensitization to methylisothiazolinone (MI), methylchloroisothiazolinone (MCI) in combination with MI and benzisothiazolinone (BIT) in Danish dermatitis patients. A retrospective epidemiological analysis of data from three Danish hospitals departments was conducted. All patients consecutively patch tested with MI, MCI/MI and BIT between 2009 and 2013 were included. MI contact allergy showed a significantly increased trend in prevalence from 1.8% in 2009 to 4.2% in 2012 (p < 0.001). Females with facial dermatitis mainly drove the increase in 2012. Adjusted logistic regression analysis showed that MI sensitization was significantly associated with occupational exposures, hand and facial dermatitis, age > 40 years, and the occupational groups of tile setters/terrazzo workers, machine operators, and painters. MCI/MI contact allergy was significantly associated with the following high-risk occupations: painting, welding (blacksmiths), machine operating, and cosmetology. The occupational group of painting was frequent in the group of patients with BIT contact allergy. Several high-risk occupations for sensitization to isothiazolinones exist. Regulation on the allowed concentration of isothiazolinones, and especially MI, in both consumer products and industrial products is needed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Epidemiology of pediatric nickel sensitivity: Retrospective review of North American Contact Dermatitis Group (NACDG) data 1994-2014.

PubMed

Warshaw, Erin M; Aschenbeck, Kelly A; DeKoven, Joel G; Maibach, Howard I; Taylor, James S; Sasseville, Denis; Belsito, Donald V; Fowler, Joseph F; Zug, Kathryn A; Zirwas, Matthew J; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Mathias, Toby

2018-04-14

Nickel is a common allergen responsible for allergic contact dermatitis. To characterize nickel sensitivity in children and compare pediatric cohorts (≤5, 6-12, and 13-18 years). Retrospective, cross-sectional analysis of 1894 pediatric patients patch tested by the North American Contact Dermatitis Group from 1994 to 2014. We evaluated demographics, rates of reaction to nickel, strength of nickel reactions, and nickel allergy sources. The frequency of nickel sensitivity was 23.7%. Children with nickel sensitivity were significantly less likely to be male (P < .0001; relative risk, 0.63; 95% confidence interval, 0.52-0.75) or have a history of allergic rhinitis (P = .0017; relative risk, 0.74; 95% confidence interval, 0.61-0.90) compared with those who were not nickel sensitive. In the nickel-sensitive cohort, the relative proportion of boys declined with age (44.8% for age ≤5, 36.6% for age 6-12, and 22.6% for age 13-18 years). The most common body site distribution for all age groups sensitive to nickel was scattered/generalized, indicating widespread dermatitis. Jewelry was the most common source associated with nickel sensitivity (36.4%). As a cross-sectional study, no long-term follow-up was available. Nickel sensitivity in children was common; the frequency was significantly higher in girls than in boys. Overall, sensitivity decreased with age. The most common source of nickel was jewelry. Published by Elsevier Inc.

Contact sensitizers in commercial hair dye products sold in Thailand.

PubMed

Boonchai, Waranya; Bunyavaree, Monthathip; Winayanuwattikun, Waranaree; Kasemsarn, Pranee

2016-04-01

Hair dyes are known to contain potent contact allergens for which sensitization rates have increased over the last decade. To examine the type and frequency of potent contact sensitizers labelled on hair dyes sold in metropolitan Bangkok, Thailand. During the 2013-2014 study period, labelled ingredient information from home use and professional hair dye products was collected. Two hundred and fifty-two hair dye products were evaluated. One hundred and forty-nine products from 48 brands were domestically produced in Thailand, and 103 products were from 23 multinational brands produced in countries other than Thailand. Two hundred and fourteen of 252 (84.9%) hair dye products were found to contain strong skin sensitizers, with 118 (46.8%) being found in domestically produced products, and 96 (38.1%) being found in multinational brand products. Thirty-eight hair dye products (15.1%) were free of potent skin sensitizers. The number of domestically produced products (31, 20.8%) that were free of potent skin sensitizers was significantly higher (p = 0.002) than the number of multinational brand products (7, 6.8%). p-Phenylenediamine was the most prevalent potent sensitizer found among domestically produced hair dyes available on the market. Our findings indicate regional differences in hair dye allergen exposure. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Via Method for Lithography Free Contact and Preservation of 2D Materials.

PubMed

Telford, Evan J; Benyamini, Avishai; Rhodes, Daniel; Wang, Da; Jung, Younghun; Zangiabadi, Amirali; Watanabe, Kenji; Taniguchi, Takashi; Jia, Shuang; Barmak, Katayun; Pasupathy, Abhay N; Dean, Cory R; Hone, James

2018-02-14

Atomically thin 2D materials span the common components of electronic circuits as metals, semiconductors, and insulators, and can manifest correlated phases such as superconductivity, charge density waves, and magnetism. An ongoing challenge in the field is to incorporate these 2D materials into multilayer heterostructures with robust electrical contacts while preventing disorder and degradation. In particular, preserving and studying air-sensitive 2D materials has presented a significant challenge since they readily oxidize under atmospheric conditions. We report a new technique for contacting 2D materials, in which metal via contacts are integrated into flakes of insulating hexagonal boron nitride, and then placed onto the desired conducting 2D layer, avoiding direct lithographic patterning onto the 2D conductor. The metal contacts are planar with the bottom surface of the boron nitride and form robust contacts to multiple 2D materials. These structures protect air-sensitive 2D materials for months with no degradation in performance. This via contact technique will provide the capability to produce "atomic printed circuit boards" that can form the basis of more complex multilayer heterostructures.

Interaural delay sensitivity and the classification of low best-frequency binaural responses in the inferior colliculus of the guinea pig.

PubMed

McAlpine, D; Jiang, D; Palmer, A R

1996-08-01

Monaural and binaural response properties of single units in the inferior colliculus (IC) of the guinea pig were investigated. Neurones were classified according to the effect of monaural stimulation of either ear alone and the effect of binaural stimulation. The majority (309/334) of IC units were excited (E) by stimulation of the contralateral ear, of which 41% (127/309) were also excited by monaural ipsilateral stimulation (EE), and the remainder (182/309) were unresponsive to monaural ipsilateral stimulation (EO). For units with best frequencies (BF) up to 3 kHz, similar proportions of EE and EO units were observed. Above 3 kHz, however, significantly more EO than EE units were observed. Units were also classified as either facilitated (F), suppressed (S), or unaffected (O) by binaural stimulation. More EO than EE units were suppressed or unaffected by binaural stimulation, and more EE than EO units were facilitated. There were more EO/S units above 1.5 kHz than below. Binaural beats were used to examine the interaural delay sensitivity of low-BF (BF < 1.5 kHz) units. The distributions of preferred interaural phases and, by extension, interaural delays, resembled those seen in other species, and those obtained using static interaural delays in the IC of the guinea pig. Units with best phase (BP) angles closer to zero generally showed binaural facilitation, whilst those with larger BPs generally showed binaural suppression. The classification of units based upon binaural stimulation with BF tones was consistent with their interaural-delay sensitivity. Characteristic delays (CD) were examined for 96 low-BF units. A clear relationship between BF and CD was observed. CDs of units with very low BFs (< 200 Hz) were long and positive, becoming progressively shorter as BF increased until, for units with BFs between 400 and 800 Hz, the majority of CDs were negative. Above 800 Hz, both positive and negative CDs were observed. A relationship between CD and characteristic phase (CP) was also observed, with CPs increasing in value as CDs became more negative. These results demonstrate that binaural processing in the guinea pig at low frequencies is similar to that reported in all other species studied. However, the dependence of CD on BF would suggest that the delay line system that sets up the interaural-delay sensitivity in the lower brainstem varies across frequency as well as within each frequency band.

Allergic contact dermatitis to benzocaine: the importance of concomitant positive patch test results.

PubMed

González-Rodríguez, A J; Gutiérrez-Paredes, E M; Revert Fernández, Á; Jordá-Cuevas, E

2013-03-01

Local anesthetics are widely used in clinical practice, and adverse effects are not uncommon. Delayed hypersensitivity reactions are among the most common effects, but immediate-type reactions may also occur. Patch testing should be considered in patients with hypersensitivity reactions. We present a case of allergic contact dermatitis to benzocaine that was detected incidentally by patch testing and highlight the importance of correctly interpreting patch test results when there are concomitant positive reactions. Copyright © 2011 Elsevier España, S.L. and AEDV. All rights reserved.

Photoallergic contact dermatitis to oxybenzone.

PubMed

Collins, P; Ferguson, J

1994-07-01

A 21-year-old woman developed an erythematous papulovesicular eruption of photo-exposed sites, following the use of an oxybenzone-containing sunscreen. Patch testing, photopatch testing, phototesting, and histology produced findings strongly suggestive of oxybenzone photoallergy. Photopatch testing with a monochromator source showed abnormal UVA responses, with evidence of immediate urticaria, and delayed-onset dermatitis. Sun-barrier use is associated with a risk of the development of contact or photocontact allergic reactions. The benzophenones are frequently used in high-protection factor sun-barrier preparations, and appear to have a particular ability to induce such responses.

Significant performance enhancement in photoconductive terahertz optoelectronics by incorporating plasmonic contact electrodes.

PubMed

Berry, C W; Wang, N; Hashemi, M R; Unlu, M; Jarrahi, M

2013-01-01

Even though the terahertz spectrum is well suited for chemical identification, material characterization, biological sensing and medical imaging, practical development of these applications has been hindered by attributes of existing terahertz optoelectronics. Here we demonstrate that the use of plasmonic contact electrodes can significantly mitigate the low-quantum efficiency performance of photoconductive terahertz optoelectronics. The use of plasmonic contact electrodes offers nanoscale carrier transport path lengths for the majority of photocarriers, increasing the number of collected photocarriers in a subpicosecond timescale and, thus, enhancing the optical-to-terahertz conversion efficiency of photoconductive terahertz emitters and the detection sensitivity of photoconductive terahertz detectors. We experimentally demonstrate 50 times higher terahertz radiation powers from a plasmonic photoconductive emitter in comparison with a similar photoconductive emitter with non-plasmonic contact electrodes, as well as 30 times higher terahertz detection sensitivities from a plasmonic photoconductive detector in comparison with a similar photoconductive detector with non-plasmonic contact electrodes.

Au/Zn Contacts to rho-InP: Electrical and Metallurgical Characteristics and the Relationship Between Them

NASA Technical Reports Server (NTRS)

Weizer, Victor G.; Fatemi, Navid S.; Korenyi-Both, Andras L.

1994-01-01

The metallurgical and electrical behavior of Au/Zn contacting metallization on p-type InP was investigated as a function of the Zn content in the metallization. It was found that ohmic behavior can be achieved with Zn concentrations as small as 0.05 atomic percent Zn. For Zn concentrations between 0.1 and 36 at. percent, the contact resistivity rho(sub c) was found to be independent of the Zn content. For low Zn concentrations the realization of ohmic behavior was found to require the growth of the compound Au2P3 at the metal-InP interface. The magnitude of rho(sub c) is shown to be very sensitive to the growth rate of the interfacial Au2P3 layer. The possibility of exploiting this sensitivity to provide low resistance contacts while avoiding the semiconductor structural damage that is normally attendant to contact formation is discussed.

Food allergy preceded by contact urticaria due to the same food: involvement of epicutaneous sensitization in food allergy.

PubMed

Inomata, Naoko; Nagashima, Mayumi; Hakuta, Amiko; Aihara, Michiko

2015-01-01

There have recently been reports suggesting that sensitization to food allergens may occur outside the intestinal tract, especially through the skin. To clarify the role of epicutaneous sensitization in food allergy, we investigated the clinical characteristics of adult patients with food allergies preceded by contact urticaria due to the same foods. We investigated clinical characteristics of 15 patients (20-51 years of age; 5 men and 10 women), who had food allergies preceded by contact urticaria. Fourteen patients were contact urticaria due to the causative foods during occupationally cooking, whereas 1 patient during face pack. In the occupational group, causative foods included rice, wheat, fruits, vegetables, fish, shrimp and cuttlefish; in the fresh cucumber paste case the cause was cucumber. In the 15 patients, the causative foods were fresh, not processed, and were tolerated by most (9/15, 60%) after heating. Regarding to symptoms after ingestion of the causative foods, the most frequently induced symptoms was oral symptoms (14/15, 93.3%), followed by urticaria (4/15, 26.7%), abdominal symptoms (3/15, 20%). The duration between the start of jobs or face pack, and the onset of contact urticaria was from 1 month to 19 years (mean, 8.7 years). The duration between the onset of contact urticaria and the onset of food allergy was from a few weeks to 6 years (mean, 11 months). One sushi cook experienced severe anaphylactic shock after ingestion of fish. In the occupational group, 13 of 15 patients (86.7%) had atopic dermatitis or hand eczema, indicating that the impaired skin barrier might be a risk for food allergies induced by epicutaneous sensitization. Epicutaneous sensitization of foods could induce food allergy under occupational cooking and skin-care treatment with foods in adults. Copyright © 2014 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Robust optimization for nonlinear time-delay dynamical system of dha regulon with cost sensitivity constraint in batch culture

NASA Astrophysics Data System (ADS)

Yuan, Jinlong; Zhang, Xu; Liu, Chongyang; Chang, Liang; Xie, Jun; Feng, Enmin; Yin, Hongchao; Xiu, Zhilong

2016-09-01

Time-delay dynamical systems, which depend on both the current state of the system and the state at delayed times, have been an active area of research in many real-world applications. In this paper, we consider a nonlinear time-delay dynamical system of dha-regulonwith unknown time-delays in batch culture of glycerol bioconversion to 1,3-propanediol induced by Klebsiella pneumonia. Some important properties and strong positive invariance are discussed. Because of the difficulty in accurately measuring the concentrations of intracellular substances and the absence of equilibrium points for the time-delay system, a quantitative biological robustness for the concentrations of intracellular substances is defined by penalizing a weighted sum of the expectation and variance of the relative deviation between system outputs before and after the time-delays are perturbed. Our goal is to determine optimal values of the time-delays. To this end, we formulate an optimization problem in which the time delays are decision variables and the cost function is to minimize the biological robustness. This optimization problem is subject to the time-delay system, parameter constraints, continuous state inequality constraints for ensuring that the concentrations of extracellular and intracellular substances lie within specified limits, a quality constraint to reflect operational requirements and a cost sensitivity constraint for ensuring that an acceptable level of the system performance is achieved. It is approximated as a sequence of nonlinear programming sub-problems through the application of constraint transcription and local smoothing approximation techniques. Due to the highly complex nature of this optimization problem, the computational cost is high. Thus, a parallel algorithm is proposed to solve these nonlinear programming sub-problems based on the filled function method. Finally, it is observed that the obtained optimal estimates for the time-delays are highly satisfactory via numerical simulations.

The noninvasive mouse ear swelling assay. II. Testing the contact sensitizing potency of fragrances.

PubMed

Thorne, P S; Hawk, C; Kaliszewski, S D; Guiney, P D

1991-11-01

The noninvasive mouse ear swelling assay (MESA) for contact allergy testing was evaluated using fragrance components and complex fragrance mixtures. The test materials represented weak sensitizers and nonsensitizers. Two versions of the MESA were investigated. Both were noninvasive and utilized only topical abdominal dosing and ear challenge with single applications in BALB/cBy mice. The vit A MESA differed from the regular MESA only in that mice were maintained on a diet with 17-fold higher levels of vitamin A (vit A) acetate beginning 3 weeks prior to induction. Sensitization reactions were determined by measuring the mean increase in ear swelling over baseline at 24, 48 and 72 hr postexposure. Irritation dose-response curves facilitated choosing a high nonirritating challenge dose. Sensitization dose-response curves were developed for cinnamaldehyde (CINN) and a complex fragrance mixture, F-16. From these curves, the SD50 was determined. This value represents the dose which sensitized half the animals and serves to rank the potency of compounds for allergic contact dermatitis and to compare values among different assays. The SD50 for CINN was 21.6% while the SD50vit A for F-16 was 26.6%. The other fragrance, isoeugenol (ISOE), and fragrance mixtures, F-07 and F-22, were also found to be weak sensitizers in the MESA and vit A MESA. The results in the MESA for CINN and ISOE were in the range observed with guinea pig test protocols but showed that the MESA was more sensitive than human test protocols. Two of the fragrance mixtures tested in the MESA gave comparable results in the Buehler guinea pig assay. However, the third (F-22) was negative in the Buehler assay and the MESA, but positive in the vit A MESA. The results of this work with weak sensitizers and the companion study (Thorne et al., 1991) with potent sensitizers at low doses illustrate that the noninvasive MESA is as sensitive as many standard guinea pig assays. In addition, it is easier and much less expensive to perform. The vit A MESA has the sensitivity and predictive power needed to test compounds and mixtures for contact sensitizing potency.

Battlefield-Acquired Immunogenicity to Metals Affects Orthopaedic Implant Outcome

DTIC Science & Technology

2016-12-01

Briatico-Vangosa G, Kaestner W, Lally C, Bontinck WJ. Nickel, cobalt and chromium in consumer products: a role in allerg ic contact dermat itis? Contact ...T, Zitting A, Jolanki R, Tarvainen K. Nickel release from metals, and a case of allergic contact dermatitis from stainless steel. Contact Dermatit is... Dermat itis 1994;31:249-55. (30) Gawkrodger DJ. Nickel sensitivity and the implantation of orthopaedic prostheses. Contact Dermatit is 1993;28:257 -9

Collagen gel droplet-embedded culture drug sensitivity testing in squamous cell carcinoma cell lines derived from human oral cancers: Optimal contact concentrations of cisplatin and fluorouracil.

PubMed

Sakuma, Kaname; Tanaka, Akira; Mataga, Izumi

2016-12-01

The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) is an anticancer drug sensitivity test that uses a method of three-dimensional culture of extremely small samples, and it is suited to primary cultures of human cancer cells. It is a useful method for oral squamous cell carcinoma (OSCC), in which the cancer tissues available for testing are limited. However, since the optimal contact concentrations of anticancer drugs have yet to be established in OSCC, CD-DST for detecting drug sensitivities of OSCC is currently performed by applying the optimal contact concentrations for stomach cancer. In the present study, squamous carcinoma cell lines from human oral cancer were used to investigate the optimal contact concentrations of cisplatin (CDDP) and fluorouracil (5-FU) during CD-DST for OSCC. CD-DST was performed in 7 squamous cell carcinoma cell lines derived from human oral cancers (Ca9-22, HSC-3, HSC-4, HO-1-N-1, KON, OSC-19 and SAS) using CDDP (0.15, 0.3, 1.25, 2.5, 5.0 and 10.0 µg/ml) and 5-FU (0.4, 0.9, 1.8, 3.8, 7.5, 15.0 and 30.0 µg/ml), and the optimal contact concentrations were calculated from the clinical response rate of OSCC to single-drug treatment and the in vitro efficacy rate curve. The optimal concentrations were 0.5 µg/ml for CDDP and 0.7 µg/ml for 5-FU. The antitumor efficacy of CDDP at this optimal contact concentration in CD-DST was compared to the antitumor efficacy in the nude mouse method. The T/C values, which were calculated as the ratio of the colony volume of the treatment group and the colony volume of the control group, at the optimal contact concentration of CDDP and of the nude mouse method were almost in agreement (P<0.05) and predicted clinical efficacy, indicating that the calculated optimal contact concentration is valid. Therefore, chemotherapy for OSCC based on anticancer drug sensitivity tests offers patients a greater freedom of choice and is likely to assume a greater importance in the selection of treatment from the perspectives of function preservation and quality of life, as well as representing a treatment option for unresectable, intractable or recurrent cases.

Analysis of TPA Pulsed-Laser-Induced Single-Event Latchup Sensitive-Area

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

Wang, Peng; Sternberg, Andrew L.; Kozub, John A.

Two-photon absorption (TPA) testing is employed to analyze the laser-induced latchup sensitive-volume (SV) of a specially designed test structure. This method takes into account the existence of an onset region in which the probability of triggering latchup transitions from zero to one as the laser pulse energy increases. This variability is attributed to pulse-to-pulse variability, uncertainty in measurement of the pulse energy, and variation in local carrier density and temperature. For each spatial position, the latchup probability associated with a given energy is calculated from multiple pulses. The latchup probability data are well-described by a Weibull distribution. The results showmore » that the area between p-n-p-n cell structures is more sensitive than the p+ and n+ source areas, and locations far from the well contacts are more sensitive than those near the contact region. The transition from low probability of latchup to high probability is more abrupt near the source contacts than it is for the surrounding areas.« less

Enhancement of the contact hypersensitivity reaction by acute morphine administration at the elicitation phase.

PubMed

Nelson, C J; How, T; Lysle, D T

1999-11-01

The present study investigated the effects of morphine on the irritant contact sensitivity (ICS) and contact hypersensitivity (CHS) reaction. ICS was induced by croton oil application on the pinnae of naïve rats. Morphine injected prior to croton oil application did not affect the ICS response when assessed by measurements of pinnae thickness. CHS was induced by applying the antigen 2,4-dinitro-1-fluorobenzene (DNFB) to the pinnae of rats sensitized to DNFB. Rats received an injection of morphine prior to either initial antigen exposure (sensitization) or antigen reexposure (challenge). Morphine prior to challenge, but not sensitization, resulted in a pronounced enhancement of the CHS response as measured by pinna thickness. Quantitative PCR also showed increased IFN-gamma mRNA levels in the inflamed tissue of morphine-treated rats. Naltrexone blocked the morphine-induced enhancement of the CHS response. The differential effects of morphine suggest that opioids have a more pronounced effect on in vivo immune responses that involve immunological memory. Copyright 1999 Academic Press.

Analysis of TPA Pulsed-Laser-Induced Single-Event Latchup Sensitive-Area

DOE PAGES

Wang, Peng; Sternberg, Andrew L.; Kozub, John A.; ...

2017-12-07

Two-photon absorption (TPA) testing is employed to analyze the laser-induced latchup sensitive-volume (SV) of a specially designed test structure. This method takes into account the existence of an onset region in which the probability of triggering latchup transitions from zero to one as the laser pulse energy increases. This variability is attributed to pulse-to-pulse variability, uncertainty in measurement of the pulse energy, and variation in local carrier density and temperature. For each spatial position, the latchup probability associated with a given energy is calculated from multiple pulses. The latchup probability data are well-described by a Weibull distribution. The results showmore » that the area between p-n-p-n cell structures is more sensitive than the p+ and n+ source areas, and locations far from the well contacts are more sensitive than those near the contact region. The transition from low probability of latchup to high probability is more abrupt near the source contacts than it is for the surrounding areas.« less

Neuro-economics in chicks: foraging choices based on amount, delay and cost.

PubMed

Matsushima, Toshiya; Kawamori, Ai; Bem-Sojka, Tiaza

2008-06-15

Studies on the foraging choices are reviewed, with an emphasis on the neural representations of elementary factors of food (i.e., amount, delay and consumption time) in the avian brain. Domestic chicks serve as an ideal animal model in this respect, as they quickly associate cue colors with subsequently supplied food rewards, and their choices are quantitatively linked with the rewards. When a pair of such color cues was simultaneously presented, the trained chicks reliably made choices according to the profitability of food associated with each color. Two forebrain regions are involved in distinct aspects of choices; i.e., nucleus accumbens-medial striatum (Ac-MSt) and arcopallium intermedium (AI), an association area in the lateral forebrain. Localized lesions of Ac-MSt enhanced delay aversion, and the ablated chicks made impulsive choices of immediate reward more frequently than sham controls. On the other hand, lesions of AI enhanced consumption-time aversion, and the ablated chicks shifted their choices toward easily consumable reward with their impulsiveness unchanged; delay and consumption time are thus doubly dissociated. Furthermore, chicks showed distinct patterns of risk-sensitive choices depending on the factor that varied at trials. Risk aversion occurred when food amount varied, whereas consistent risk sensitivity was not found when the delay varied; amount and delay were not interchangeable. Choices are thus deviated from those predicted as optima. Instead, factors such as amount, delay and consumption time could be separately represented and processed to yield economically sub-optimal choices.

Comparison of the yield of tuberculosis among contacts of multidrug-resistant and drug-sensitive tuberculosis patients in Ethiopia using GeneXpert as a primary diagnostic test.

PubMed

Hiruy, Nebiyu; Melese, Muluken; Habte, Dereje; Jerene, Degu; Gashu, Zewdu; Alem, Genetu; Jemal, Ilili; Tessema, Belay; Belayneh, Beza; Suarez, Pedro G

2018-06-01

This study compared the yield of tuberculosis (TB) among contacts of multidrug-resistant tuberculosis (MDR-TB) index cases with that in drug-sensitive TB (DS-TB) index cases in a program setting. A comparative cross-sectional study was conducted among contacts of sputum smear-positive new DS-TB index cases and MDR-TB index cases. After contacts were screened, GeneXpert was used for the diagnosis of TB. The study included 111 MDR-TB and 119 DS-TB index cases. A total of 340 and 393 contacts of MDR-TB and DS-TB index cases, respectively, were traced, of whom 331 among MDR-TB contacts and 353 among DS-TB contacts were screened. There were 20 (6%) presumptive TB cases for MDR-TB contacts and 41 (11%) for DS-TB contacts. The prevalence of TB among MDR-TB contacts was 2.7% and among DS-TB contacts was 4.0%. The majority of the MDR-TB contacts diagnosed with TB had MDR-TB; the reverse was true for DS-TB. The yield of TB among contacts of MDR-TB and DS-TB patients using GeneXpert was high as compared to the population-level prevalence. The likelihood of diagnosing rifampicin-resistant TB among contacts of MDR-TB index cases was higher in comparison with contacts of DS-TB index cases. The use of GeneXpert in DS-TB contact investigation has the added advantage of diagnosing rifampicin-resistant TB cases when compared to the use of the nationally recommended acid-fast bacillus (AFB) microscopy for DS-TB contact investigation. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Synthesis of Deoxyribonucleic Acid After Ultraviolet Irradiation of Sensitive and Resistant Haemophilus influenzae

PubMed Central

Modak, Sohan P.; Setlow, Jane K.

1969-01-01

Synthesis of deoxyribonucleic acid (DNA) has been measured as a function of ultraviolet (UV) radiation dose in wild-type and seven UV-sensitive strains of Haemophilus influenzae. At the UV doses used, all strains were able to resume DNA synthesis, even those which are unable to excise pyrimidine dimers from their DNA. These excisionless strains showed longer UV-induced delays in DNA synthesis than all but one of the other strains. The longest delay was shown by DB117, a strain which can excise dimers but which is recombination deficient and unable to rejoin X ray-induced single-strand breaks. All strains showed a progressive decrease in sensitivity as they approached the stationary phase. PMID:5305934

75 FR 65230 - Drawbridge Operation Regulation; Arkansas Waterway, Pine Bluff, AR

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-22

... requesting a draw opening. This keying will activate an indicator on the remote drawbridge operator's console... operated. Vessels requesting an opening shall establish contact by radio/telephone with the remote... drawspan opening delays experienced previously from missed calls under the prior regulatory guidance...

75 FR 66306 - Drawbridge Operation Regulation; Arkansas Waterway, Little Rock, AR

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-28

... a draw opening. This keying will activate an indicator on the remote drawbridge operator's console... position and is remotely operated. Vessels requesting an opening shall establish contact by radio/telephone... drawspan opening delays experienced previously from missed calls under the prior regulatory guidance...

Assessing Impact of Distributions and Dependencies in Analysis of Alternatives of System of Systems: Phase 3

DTIC Science & Technology

2013-12-19

32 3.3 An Approach for Evaluating System-of-Systems Operational Benefits of a...delay of a flight under IMC ............................................... 41 Figure 15: Sensitivity of delay of each of the four segments to...85 Figure 43: Generic SoS node behaviors

Acute and delayed effects of intermittant ozone on cardiovascular and thermoregulatory responses of young and aged rats

EPA Science Inventory

Ozone (03) is associated with cardiovascular and respiratory diseases. The aged population is considered to be more sensitive to air pollutants but relatively few studies have demonstrated increased susceptibility in animal models of aging. To study the acute and delayed physiolo...

Wound-Related Allergic/Irritant Contact Dermatitis.

PubMed

Alavi, Afsaneh; Sibbald, R Gary; Ladizinski, Barry; Saraiya, Ami; Lee, Kachiu C; Skotnicki-Grant, Sandy; Maibach, Howard

2016-06-01

To provide information from a literature review about the prevention, recognition, and treatment for contact dermatitis. This continuing education activity is intended for physicians and nurses with an interest in skin and wound care. After participating in this educational activity, the participant should be better able to:1. Identify signs and symptoms of and diagnostic measures for contact dermatitis.2. Identify causes and risks for contact dermatitis.3. Select appropriate treatment for contact dermatitis and its prevention. Contact dermatitis to wound care products is a common, often neglected problem. A review was conducted to identify articles relevant to contact dermatitis.A PubMed English-language literature review was conducted for appropriate articles published between January 2000 and December 2015.Contact dermatitis is both irritant (80% of cases) or allergic (20% of cases). Frequent use of potential contact allergens and impaired barrier function of the skin can lead to rising sensitization in patients with chronic wounds. Common known allergens to avoid in wound care patients include fragrances, colophony, lanolin, and topical antibiotics.Clinicians should be cognizant of the allergens in wound care products and the potential for sensitization. All medical devices, including wound dressings, adhesives, and bandages, should be labeled with their complete ingredients, and manufacturers should be encouraged to remove common allergens from wound care products, including topical creams, ointments, and dressings.

Method for Ultrasonic Imaging and Device for Performing the Method

NASA Technical Reports Server (NTRS)

Madaras, Eric I. (Inventor)

1997-01-01

A method for ultrasonic imaging of interior structures and flaws in a test specimen with a smooth or irregular contact surfaces, in which an ultrasonic transducer is coupled acoustically to the contact surface via a plurality of ultrasonic wave guides with equal delay times. The wave guides are thin and bendable, so they adapt to variations in the distance between the transducer and different parts of the contact surface by bending more or less. All parts of the irregular contact surface accordingly receive sound waves that are in phase, even when the contact surface is irregular, so a coherent sound wave is infused in the test specimen. The wave guides can be arranged in the form of an ultrasonic brush, with a flat head for coupling to a flat transducer, and free bristles that can be pressed against the test specimen. By bevelling the bristle ends at a suitable angle, shear mode waves can be infused into the test specimen from a longitudinal mode transducer.

The Unique Molecular Signatures of Contact Dermatitis and Implications for Treatment.

PubMed

Leonard, Alexandra; Guttman-Yassky, Emma

2018-05-12

Irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD) are common skin disorders that are characterized by inflammation, oozing, crusting, and pruritus. Atopic dermatitis (AD) is an inflammatory skin disease characterized by immune and barrier abnormalities and is additionally a risk factor for acquiring ICD and ACD. New work on allergic sensitization to common allergens (e.g., nickel and fragrance) in human skin has shown that different allergens have distinct molecular fingerprinting. For example, nickel promotes strong Th1/Th17 polarization, whereas fragrance allergy causes Th2/Th22 skewing, which is similar to the phenotype of AD. While ACD has previously been considered to be constant across all allergens, largely based on mouse models involving strong sensitizers, these new data suggest that ACD differs mechanistically according to allergen. Further, ACD in the setting of concurrent AD shows a different and attenuated phenotype as compared to healthy individuals with ACD, which influences the way AD patients respond to vaccination and other treatment modalities. As in contact sensitization, skin challenged by food patch testing shows that common food allergens (e.g., peanut and barley) also cause distinct immune polarizations in the skin. Additionally, house dust mite reactions in human skin have been profiled to show unique Th2, Th9, and Th17/22 activation as compared to controls, which are similar to the phenotype of psoriasis and contact responses to nickel. Given this information, ACD patients should be treated based on their unique allergen polarity. Refined understanding of the molecular behavior of contact dermatitis and related diseases translates to improved methods of inducing tolerance in sensitized allergic patients, such as with targeted drug therapy and epicutaneous immunotherapy.

Reduced Sensitivity to Sooner Reward During Intertemporal Decision-Making Following Insula Damage in Humans

PubMed Central

Sellitto, Manuela; Ciaramelli, Elisa; Mattioli, Flavia; di Pellegrino, Giuseppe

2016-01-01

During intertemporal choice, humans tend to prefer small-sooner rewards over larger-delayed rewards, reflecting temporal discounting (TD) of delayed outcomes. Functional neuroimaging (fMRI) evidence has implicated the insular cortex in time-sensitive decisions, yet it is not clear whether activity in this brain region is crucial for, or merely associated with, TD behavior. Here, patients with damage to the insula (Insular patients), control patients with lesions outside the insula, and healthy individuals chose between smaller-sooner and larger-later monetary rewards. Insular patients were less sensitive to sooner rewards than were the control groups, exhibiting reduced TD. A Voxel-based Lesion-Symptom Mapping (VLSM) analysis confirmed a statistically significant association between insular damage and reduced TD. These results indicate that the insular cortex is crucial for intertemporal choice. We suggest that he insula may be necessary to anticipate the bodily/emotional effects of receiving rewards at different delays, influencing the computation of their incentive value. Devoid of such input, insular patients’ choices would be governed by a heuristic of quantity, allowing patients to wait for larger options. PMID:26793084

"Contacting" the Fundamentals: A New Paradigm for Pedagogy

ERIC Educational Resources Information Center

Munjee, Tara

2012-01-01

Contact improvisation can serve as a way to access new understandings of Bartenieff Fundamentals. Inherent elements of contact improvisation such as thinking and feeling bodily in the moment, sensitivity to activated weight along with weight sharing and bearing, flow, whole-body organization, and immediacy of embodied presence provide fertile…

Poison plants (image)

MedlinePlus

... by poor circulation, even stress. An example of contact dermatitis is the reaction of a sensitive person's skin to poison ivy, oak or sumac. Contact with these plants, which contain a chemical called ...

Combustion heater for oil shale

DOEpatents

Mallon, R.; Walton, O.; Lewis, A.E.; Braun, R.

1983-09-21

A combustion heater for oil shale heats particles of spent oil shale containing unburned char by burning the char. A delayed fall is produced by flowing the shale particles down through a stack of downwardly sloped overlapping baffles alternately extending from opposite sides of a vertical column. The delayed fall and flow reversal occurring in passing from each baffle to the next increase the residence time and increase the contact of the oil shale particles with combustion supporting gas flowed across the column to heat the shale to about 650 to 700/sup 0/C for use as a process heat source.

Combustion heater for oil shale

DOEpatents

Mallon, Richard G.; Walton, Otis R.; Lewis, Arthur E.; Braun, Robert L.

1985-01-01

A combustion heater for oil shale heats particles of spent oil shale containing unburned char by burning the char. A delayed fall is produced by flowing the shale particles down through a stack of downwardly sloped overlapping baffles alternately extending from opposite sides of a vertical column. The delayed fall and flow reversal occurring in passing from each baffle to the next increase the residence time and increase the contact of the oil shale particles with combustion supporting gas flowed across the column to heat the shale to about 650.degree.-700.degree. C. for use as a process heat source.

Individual differences in discount rate are associated with demand for self-administered cocaine, but not sucrose.

PubMed

Koffarnus, Mikhail N; Woods, James H

2013-01-01

Substance abusers, including cocaine abusers, discount delayed rewards to a greater extent than do matched controls. In the current experiment, individual differences in discounting of delayed rewards in rats (choice of one immediate over three delayed sucrose pellets) were assessed for associations with demand for either sucrose pellets or an intravenous dose of 0.1 mg/kg/infusion cocaine. Twenty-four male Sprague Dawley rats were split into three groups based on sensitivity to delay to reinforcement. Then, demand for sucrose pellets and cocaine was determined across a range of fixed-ratio values. Delay discounting was then reassessed to determine the stability of this measure over the course of the experiment. Individual differences in impulsive choice were positively associated with elasticity of demand for cocaine, a measure of reinforcer value, indicating that rats having higher discount rates also valued cocaine more. Impulsive choice was not associated with the level of cocaine consumption as price approached 0 or with any parameter associated with demand for sucrose. Individual sensitivity to delay was correlated with the initial assessment when reassessed at the end of the experiment, although impulsive choice increased for this cohort of rats as a whole. These findings suggest that impulsive choice in rats is positively associated with valuation of cocaine, but not sucrose. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of Addiction.

The Influences of Face Inversion and Facial Expression on Sensitivity to Eye Contact in High-Functioning Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Vida, Mark D.; Maurer, Daphne; Calder, Andrew J.; Rhodes, Gillian; Walsh, Jennifer A.; Pachai, Matthew V.; Rutherford, M. D.

2013-01-01

We examined the influences of face inversion and facial expression on sensitivity to eye contact in high-functioning adults with and without an autism spectrum disorder (ASD). Participants judged the direction of gaze of angry, fearful, and neutral faces. In the typical group only, the range of directions of gaze leading to the perception of eye…

Contact allergic gastritis: an underdiagnosed entity?

PubMed Central

Pföhler, Claudia; Körner, Rebecca; Vogt, Thomas; Müller, Cornelia S L

2012-01-01

Only a few cases of contact allergic gastritis in patients with nickel allergy have been reported. We report a case of probable contact-allergic gastritis in a 46-year-old woman. Clinical examination revealed lichenoid mucosal lesions of the gums adjacent to bridges and crowns that had been implanted several weeks back. Since implantation, the patient had suffered from gastrointestinal complaints (including stomach pain). Gastroscopy showed eosinophilic gastritis. Patch testing done under the diagnosis of contact allergic stomatitis showed positive reactions to: gold sodium thiosulphate; manganese (II) chloride; nickel (II) sulphate; palladium chloride; vanadium (III) chloride and zirconium (IV) chloride. The crowns and bridge contained gold, palladium and zirconium chloride, hence they were replaced by titan-based dentition. Shortly after replacing the artificial dentition, all gastrointestinal symptoms resolved spontaneously without further treatment. Delayed-type allergy against the components of artificial dentition seemed to be the cause of gastritis. PMID:23192576

Glucose-sensitive silicone hydrogel contact lens toward tear glucose monitoring.

PubMed

Badugu, Ramachandram; Reece, Edward Albert; Lakowicz, Joseph R

2018-05-01

Accurate and reliable monitoring of blood glucose is needed for the treatment of diabetes, which has many challenges, including lack of patient compliance. Measuring tear glucose is an alternative to traditional finger-stick tests used to track blood sugar levels, but glucose sensing using tears has yet to be achieved. We report a methodology for possible tear glucose monitoring using glucose-sensitive silicone hydrogel (SiHG) contact lenses, the primary type of lenses available in today's market. Initially, we assessed the interpenetrating polymer network, with nearly pure silicone and water regions, existing in the SiHGs using a polarity-sensitive probe Prodan. We then synthesized a glucose-sensitive fluorophore Quin-C18 with a hydrophobic side chain for localization of probe at the interfacial region. Using our glucose-sensing contact lens, we were able to measure varying concentrations of glucose in an in-vitro system. The Quin-C18 strongly bound to the lenses with insignificant leaching even after multiple rinses. The lenses displayed a similar response to glucose after three months of storage in water. This study demonstrates that it may be possible to develop a contact lens for continuous glucose monitoring in the near term, using our concept of fluorophore binding at the silicone-water interface. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

Precise estimation of tropospheric path delays with GPS techniques

NASA Technical Reports Server (NTRS)

Lichten, S. M.

1990-01-01

Tropospheric path delays are a major source of error in deep space tracking. However, the tropospheric-induced delay at tracking sites can be calibrated using measurements of Global Positioning System (GPS) satellites. A series of experiments has demonstrated the high sensitivity of GPS to tropospheric delays. A variety of tests and comparisons indicates that current accuracy of the GPS zenith tropospheric delay estimates is better than 1-cm root-mean-square over many hours, sampled continuously at intervals of six minutes. These results are consistent with expectations from covariance analyses. The covariance analyses also indicate that by the mid-1990s, when the GPS constellation is complete and the Deep Space Network is equipped with advanced GPS receivers, zenith tropospheric delay accuracy with GPS will improve further to 0.5 cm or better.

Auditing the use and assessing the clinical utility of microscopy as a point-of-care test for Neisseria gonorrhoeae in a Sexual Health clinic.

PubMed

Mensforth, Sarah; Thorley, Nicola; Radcliffe, Keith

2018-02-01

We assessed whether urethral microscopy was performed as per clinic protocol for male clinic attendees reporting contact with Neisseria gonorrhoeae (GC), urethral symptoms or given a diagnosis of epididymo-orchitis (EO) over a 12-month period (9732 patients). Prevalence of gonorrhoea in the contacts, urethral symptoms and EO groups was 50, 12.7 and 1.6%, respectively. Microscopy was performed reliably for contacts (96%), those with discharge/dysuria with evidence of urethritis on examination (98%), but not those with EO (43%). We explored the clinical utility of microscopy as a point-of-care test for identifying urethral GC in each subgroup, using the APTIMA Combo 2 CT/GC nucleic acid amplification test as the comparator (1710 patients). Sensitivity of microscopy for each subgroup was good; there was no statistical difference between subgroup sensitivity using Fisher's exact test. Microscopy is valuable to ensure prompt diagnosis and contact tracing. All GC contacts were treated 'epidemiologically'; however, half of GC contacts did not have GC. Microscopy identified the majority of GC cases, including amongst contacts (71% of heterosexual contacts, 66% of contacts reporting sex with men). We propose that epidemiological treatment for GC contacts should be reconsidered on the grounds of antibiotic stewardship, favouring use of microscopy to guide treatment decisions.

T Cell Dynamic Activation and Functional Analysis in Nanoliter Droplet Microarray.

PubMed

Sarkar, Saheli; Motwani, Vinny; Sabhachandani, Pooja; Cohen, Noa; Konry, Tania

2015-06-01

Characterization of the heterogeneity in immune reactions requires assessing dynamic single cell responses as well as interactions between the various immune cell subsets. Maturation and activation of effector cells is regulated by cell contact-dependent and soluble factor-mediated paracrine signalling. Currently there are few methods available that allow dynamic investigation of both processes simultaneously without physically constraining non-adherent cells and eliminating crosstalk from neighboring cell pairs. We describe here a microfluidic droplet microarray platform that permits rapid functional analysis of single cell responses and co-encapsulation of heterotypic cell pairs, thereby allowing us to evaluate the dynamic activation state of primary T cells. The microfluidic droplet platform enables generation and docking of monodisperse nanoliter volume (0.523 nl) droplets, with the capacity of monitoring a thousand droplets per experiment. Single human T cells were encapsulated in droplets and stimulated on-chip with the calcium ionophore ionomycin. T cells were also co-encapsulated with dendritic cells activated by ovalbumin peptide, followed by dynamic calcium signal monitoring. Ionomycin-stimulated cells depicted fluctuation in calcium signalling compared to control. Both cell populations demonstrated marked heterogeneity in responses. Calcium signalling was observed in T cells immediately following contact with DCs, suggesting an early activation signal. T cells further showed non-contact mediated increase in calcium level, although this response was delayed compared to contact-mediated signals. Our results suggest that this nanoliter droplet array-based microfluidic platform is a promising technique for assessment of heterogeneity in various types of cellular responses, detection of early/delayed signalling events and live cell phenotyping of immune cells.

Cluster of Ebola Virus Disease, Bong and Montserrado Counties, Liberia.

PubMed

Nyenswah, Tolbert G; Fallah, Mosaka; Calvert, Geoffrey M; Duwor, Stanley; Hamilton, E Dutch; Mokashi, Vishwesh; Arzoaquoi, Sampson; Dweh, Emmanuel; Burbach, Ryan; Dlouhy, Diane; Oeltmann, John E; Moonan, Patrick K

2015-07-01

Lack of trust in government-supported services after the death of a health care worker with symptoms of Ebola resulted in ongoing Ebola transmission in 2 Liberia counties. Ebola transmission was facilitated by attempts to avoid cremation of the deceased patient and delays in identifying and monitoring contacts.

Prevalence of Contact Allergens in Personal Care Products for Babies and Children.

PubMed

Bonchak, Jonathan G; Prouty, Megan E; de la Feld, Salma F

Personal care products marketed for babies and children are often regarded as "safe" or "gentle." However, little is known about the prevalence of contact allergens in these types of products. This study assessed the prevalence of important sensitizers in personal care products marketed for babies and children. A secondary objective of this study was to determine whether a product's cost correlates with content of sensitizing ingredients. The ingredient lists of 533 unique personal care products were analyzed for presence of fragrance, betaines, propylene glycol, methylchloroisothiazolinone, methylisothiazolinone, formaldehyde, lanolin, and neomycin. Price per ounce was determined for each product as well. Most personal care products for babies and children contain 1 or more sensitizers. Products containing more sensitizers tend to cost less than those without any sensitizing ingredients.

Delayed Hospital Presentation in Acute Decompensated Heart Failure: Clinical and Patient Reported Factors

PubMed Central

Darling, Chad; Saczynski, Jane S.; McManus, David D.; Lessard, Darleen; Spencer, Frederick A.; Goldberg, Robert J.

2013-01-01

Background Patients with acute decompensated heart failure (ADHF) often wait a considerable amount of time before going to the hospital. Prior studies have examined the reasons why such delays may occur, but additional studies are needed to identify modifiable factors contributing to these delays. Purpose To describe care-seeking delay times, factors associated with prolonged delay, and patient's thoughts and actions in adult men and women hospitalized with ADHF. Methods We surveyed 1,271 patients hospitalized with ADHF at 8 urban medical centers between 2007 and 2010. Results The average age of our study population was 73 years, 47% were female, and 72% had prior heart failure. The median duration of pre-hospital delay prior to hospital presentation was 5.3 hours. Patients who delayed longer than the median were older, more likely to have diabetes, peripheral edema, to have symptoms that began in the afternoon, and to have contacted their medical provider(s) about their symptoms. Prolonged care seekers were less likely to have attributed their symptoms to ADHF, less likely to want to have bothered their doctor or family, and were more likely to be concerned about missing work due to their illness (all p values<0.05). Conclusions Care-seeking delays are common among patients with ADHF. A variety of factors contribute to these delays which in some cases may represent efforts to manage ADHF symptoms at home. More research is needed to better understand the detrimental effects of these delays and how best to encourage timely care-seeking behavior in the setting of ADHF. PMID:23474108

Measurement of the response time of the delay window for the neutron converter of the SPIRAL2 project

NASA Astrophysics Data System (ADS)

Acosta, G.; Andre, T.; Bermudez, J.; Blinov, M. F.; Jamet, C.; Logatchev, P. V.; Semenov, Y. I.; Starostenko, A. A.; Tecchio, L. B.; Tsyganov, A. S.; Udup, E.; Vasquez, J.

2014-09-01

Research and development of a safety system for the SPIRAL2 facility has been conceived to protect the UCx target from a possible interaction with the 200 kW deuteron beam. The system called "delay window" (DW) is designed as an integral part of the neutron converter module and is located in between the neutron converter and the fission target. The device has been designed as a barrier, located directly behind the neutron converter on the axis of the deuteron beam, with the purpose of "delaying" the eventual interaction of the deuteron beam with the UCx target in case of a failure of the neutron converter. The "delay" must be long enough to allow the interlock to react and safely stop the beam operation, before the beam will reach the UCx target. The working concept of the DW is based on the principle of the electrical fuse. Electrically insulated wires placed on the surface of a Tantalum disk assure a so called "free contact", normally closed to an electronic circuit located on the HV platform, far from the radioactive environment. The melting temperature of the wires is much less than Tantalum. Once the beam is impinging on the disk, one or more wires are melted and the "free contact" is open. A solid state relay is changing its state and a signal is sent to the interlock device. A prototype of the DW has been constructed and tested with an electron beam of power density equivalent to the SPIRAL2 beam. The measured "delay" is 682.5 ms (σ=116 ms), that is rather long in comparison to the intrinsic delays introduced by the detectors itself (2 ms) and by the associated electronic devices (120 ns). The experimental results confirm that, in the case of a failure of the neutron converter, the DW as conceived is enable to withstand the beam power for a period of time sufficiently long to safely shut down the SPIRAL2 accelerator.

Failures in risk assessment and risk management for cosmetic preservatives in Europe and the impact on public health.

PubMed

Schwensen, Jakob F; White, Ian R; Thyssen, Jacob P; Menné, Torkil; Johansen, Jeanne D

2015-09-01

In view of the current and unprecedented increase in contact allergy to methylisothiazolinone (MI), we characterized and evaluated two recent epidemics of contact allergy to preservatives used in cosmetic products to address failures in risk assessment and risk management. To evaluate temporal trends of preservative contact allergy. The study population included consecutive patch tested eczema patients seen at a university hospital between 1985 and 2013. A total of 23 138 patients were investigated for a contact allergy. The overall prevalence of contact allergy to at least one preservative increased significantly over the study period, from 6.7% in 1985 to 11.8% in 2013 (p < 0.001). Importantly, the preservatives methyldibromo glutaronitrile and MI rapidly resulted in high sensitization prevalence rates, which reached epidemic proportions. Although the proportion of patients with current clinical disease attributable to methyldibromo glutaronitrile contact allergy decreased significantly following the ban on its use in cosmetic products (p < 0.001), the sudden and high proportion of current sensitization to MI requires immediate attention (p < 0.001). The introduction of new preservatives in Europe with inadequate pre-market risk assessment has rapidly increased the overall burden of cutaneous disease caused by preservatives. We suggest that the cosmetic industry has a responsibility to react faster and replace troublesome preservatives when a preservative contact allergy epidemic is recognized, but the European Commission has the ultimate responsibility for failures in risk management after new, major sensitizing preservatives are introduced onto the market. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Managing latex allergies at home

MedlinePlus

Latex products; Latex allergy; Latex sensitivity; Contact dermatitis - latex allergy ... Habif TP. Contact dermatitis and patch testing. In: Habif TP, ed. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 6th ed. ...

Incident Mycobacterium tuberculosis infection in household contacts of infectious tuberculosis patients in Brazil.

PubMed

Jones-López, Edward C; Acuña-Villaorduña, Carlos; Fregona, Geisa; Marques-Rodrigues, Patricia; White, Laura F; Hadad, David Jamil; Dutra-Molina, Lucilia Pereira; Vinhas, Solange; McIntosh, Avery I; Gaeddert, Mary; Ribeiro-Rodrigues, Rodrigo; Salgame, Padmini; Palaci, Moises; Alland, David; Ellner, Jerrold J; Dietze, Reynaldo

2017-08-18

In household contact investigations of tuberculosis (TB), a second tuberculin skin test (TST) obtained several weeks after a first negative result consistently identifies individuals that undergo TST conversion. It remains unclear whether this delay in M. tuberculosis infection is related to differences in the infectious exposure, TST boosting, partial host resistance, or some other factor. We conducted a household contact study Vitória, Brazil. Between 2008 and 2013, we identified culture-positive pulmonary TB patients and evaluated their household contacts with both a TST and interferon gamma release assay (IGRA), and identified TST converters at 8-12 weeks post study enrollment. Contacts were classified as TST-positive (≥10 mm) at baseline, TST converters, or persistently TST-negative. We compared TST converters to TST-positive and to TST-negative contacts separately, using generalized estimating equations. We enrolled 160 index patients and 838 contacts; 523 (62.4%) were TST+, 62 (7.4%) TST converters, and 253 (30.2%) TST-. TST converters were frequently IGRA- at 8-12 weeks. In adjusted analyses, characteristics distinguishing TST converters from TST+ contacts (no contact with another TB patient and residence ownership) were different than those differentiating them from TST- contacts (stronger cough in index patient and contact BCG scar). The individual risk and timing of M. tuberculosis infection within households is variable and dependent on index patient, contact and environmental factors within the household, and the surrounding community. Our findings suggest a threshold effect in the risk of infection in humans.

Tuberculosis in a South African prison – a transmission modelling analysis

PubMed Central

Johnstone-Robertson, Simon; Lawn, Stephen D; Welte, Alex; Bekker, Linda-Gail; Wood, Robin

2015-01-01

Background Prisons are recognised internationally as institutions with very high tuberculosis (TB) burdens where transmission is predominantly determined by contact between infectious and susceptible prisoners. A recent South African court case described the conditions under which prisoners awaiting trial were kept. With the use of these data, a mathematical model was developed to explore the interactions between incarceration conditions and TB control measures. Methods Cell dimensions, cell occupancy, lock-up time, TB incidence and treatment delays were derived from court evidence and judicial reports. Using the Wells-Riley equation and probability analyses of contact between prisoners, we estimated the current TB transmission probability within prison cells, and estimated transmission probabilities of improved levels of case finding in combination with implementation of national and international minimum standards for incarceration. Results Levels of overcrowding (230%) in communal cells and poor TB case finding result in annual TB transmission risks of 90% per annum. Implementing current national or international cell occupancy recommendations would reduce TB transmission probabilities by 30% and 50%, respectively. Improved passive case finding, modest ventilation increase or decreased lock-up time would minimally impact on transmission if introduced individually. However, active case finding together with implementation of minimum national and international standards of incarceration could reduce transmission by 50% and 94%, respectively. Conclusions Current conditions of detention for awaiting-trial prisoners are highly conducive for spread of drug-sensitive and drug-resistant TB. Combinations of simple well-established scientific control measures should be implemented urgently. PMID:22272961

The irritation potential and reservoir effect of mild soaps.

PubMed

Lodén, Marie; Buraczewska, Izabela; Edlund, Fredrik

2003-08-01

Identification and reduction of external noxious factors is one key point in the strategy for the treatment and reduction of contact dermatitis. A wide variety of soaps on the market are claimed to be suitable for the use on sensitive skin due to their mildness. The aim of the present study was to illustrate possible differences in the irritation potential of 8 products and to investigate whether surfactant residues may form an irritant reservoir on the skin. The study was double-blind, randomized using healthy human volunteers. The inherent capacity of the products to induce irritation was determined using conventional patch test technique, whereas detection of potential surfactant residues on the skin was done using a methodology developed in the 1960s for detection of the corticosteroid reservoir in the stratum corneum. The method comprised the release of active substance from the stratum corneum reservoir by occlusion of the skin with an aluminium chamber, followed by evaluation of the biological response. In the present study, the soap-treated area was rinsed with water and then occluded. Instrumental measurements of the transepidermal water loss and superficial skin blood flow served as indicators of the injurious effects of the products. The results showed large differences in irritation potential between the products, and some of them demonstrated considerable damaging effect. Moreover, the study proved the presence of barrier-impairing residues on the skin after rinsing with water. Subclinical skin damage can make the skin vulnerable to further irritation and delay recovery of chronic irritant contact dermatitis.

[News on occupational contact dermatitis].

PubMed

Crépy, Marie-Noëlle; Bensefa-Colas, Lynda

2014-03-01

Contact dermatitis--irritant contact dermatitis, allergic contact dermatitis and protein contact dermatitis--are the most common occupational skin diseases, most often localized to the hands. Contact urticaria is rarer The main occupational irritants are wet work, detergents and disinfectants, cutting oils, and solvents. The main occupational allergens are rubber additives, metals (chromium, nickel, cobalt), plastics (epoxy resins, acrylic), biocides and plants. Diagnosis is based on clinical examination, medical history and allergy testing. For a number of irritating or sensitizing agents, irritant or allergic dermatitis can be notified as occupational diseases. The two main prevention measures are reducing skin contact with irritants and complete avoidance of skin contact with offending allergens.

Contact allergy to ingredients of hair cosmetics - a comparison of female hairdressers and clients based on IVDK 2007-2012 data.

PubMed

Uter, Wolfgang; Gefeller, Olaf; John, Swen Malte; Schnuch, Axel; Geier, Johannes

2014-07-01

Cosmetics for bleaching, waving/relaxing and dyeing hair contain well-known allergens, leading to a substantial number of cases of allergic contact dermatitis. To compare the frequency of important contact allergens (i) between two distinct groups of exposed patients, and (ii) with previous surveillance data. On the basis of data collected by the Information Network of Departments of Dermatology (IVDK; www.ivkd.org) between 2007 and 2012 in 824 female hairdressers and 2067 female clients, the current spectrum of contact sensitization to ingredients of hair cosmetics, as contained in different pertinent series, is described. A similar burden of sensitization as in previous analyses was observed, but with some increase in sensitization to oxidative hair dye components in clients. Some allergens mainly affected hairdressers, such as ammonium persulfate (18.7% positive) and glyceryl monothioglycolate (GMTG; still 4.7% positive, with a few cases also in young hairdressers, despite removal from the German market). Hair dyes remain important contact allergens, despite various attempts by the cosmetic industry to introduce hair dyes with lower allergenic potential. The re-emergence of GMTG as an occupational allergen should be considered as a warning signal ('sentinel event') prompting close monitoring. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Can we improve the prevention and detection of congenital abnormalities? An audit of early pregnancy care in New Zealand.

PubMed

Arroll, Nicola; Sadler, Lynn; Stone, Peter; Masson, Vicki; Farquhar, Cindy

2013-08-16

To determine whether there were "quality gaps" in the provision of care during pregnancies that resulted in a perinatal death due to congenital abnormality. Perinatal deaths from congenital cardiovascular, central nervous system or chromosomal abnormality in 2010 were identified retrospectively. Data were extracted by retrospective clinical note review and obtained by independent review of ultrasound scans. There were 137 perinatal deaths due to a congenital cardiovascular (35), central nervous system (29) or chromosomal abnormality (73). First contact with a health professional during pregnancy was predominantly with a general practitioner. First contact occurred within 14 weeks in 85% of pregnancies and there was often a significant delay before booking. Folate supplements were taken by 7% pre-conceptually and 54% of women in the antenatal period. There were 20 perinatal deaths from neural tube defects that could potentially have been prevented through the use of pre-conceptual folate. Antenatal screening was offered to 75% of the women who presented prior to 20 weeks and 84% of these undertook at least one of the available antenatal screening tests. Review of ultrasound images found five abnormalities could have been detected earlier. Delay in booking or failure to offer screening early were the most common reasons for delay in diagnosis of screen detectable abnormalities. The preventative value and timing of (pre-conceptual) folate needs emphasis.

Delay-induced stochastic bifurcations in a bistable system under white noise

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

Sun, Zhongkui, E-mail: sunzk@nwpu.edu.cn; Fu, Jin; Xu, Wei

2015-08-15

In this paper, the effects of noise and time delay on stochastic bifurcations are investigated theoretically and numerically in a time-delayed Duffing-Van der Pol oscillator subjected to white noise. Due to the time delay, the random response is not Markovian. Thereby, approximate methods have been adopted to obtain the Fokker-Planck-Kolmogorov equation and the stationary probability density function for amplitude of the response. Based on the knowledge that stochastic bifurcation is characterized by the qualitative properties of the steady-state probability distribution, it is found that time delay and feedback intensity as well as noise intensity will induce the appearance of stochasticmore » P-bifurcation. Besides, results demonstrated that the effects of the strength of the delayed displacement feedback on stochastic bifurcation are accompanied by the sensitive dependence on time delay. Furthermore, the results from numerical simulations best confirm the effectiveness of the theoretical analyses.« less

Cannibalistic Predator-Prey Model with Disease in Predator — A Delay Model

NASA Astrophysics Data System (ADS)

Biswas, Santosh; Samanta, Sudip; Chattopadhyay, Joydev

In this paper, we propose and analyze a cannibalistic predator-prey model with a transmissible disease in the predator population. The disease can be transmitted through contacts with infected individuals as well as the cannibalism of an infected predator. We also consider incubation delay in disease transmission, where the incubation period represents the time in which the infectious agent develops in the host. Local stability analysis of the system around the biologically feasible equilibria is studied. Bifurcation analysis of the system around interior equilibrium is also studied. Applying the normal form theory and central manifold theorem, the direction of Hopf bifurcation, the stability and the period of bifurcating periodic solutions are derived. Under appropriate conditions, the permanence of the system with time delay is proved. Our results suggest that incubation delay destabilizes the system and can produce chaos. We also observe that cannibalism can control disease and population oscillations. Extensive numerical simulations are performed to support our analytical results.

Clinical assessment of blood glucose homeostasis in horses: comparison of a continuous glucose monitoring system with a combined intravenous glucose and insulin test protocol.

PubMed

Johnson, P J; Wiedmeyer, C E; LaCarrubba, A; Messer, N T; Dingfelder, H A; Cogswell, A M; Amorim, J R R; Ganjam, V K

2011-01-01

The combined glucose-insulin test (CGIT) is helpful for evaluating insulin sensitivity. A continuous glucose monitoring system (CGMS) reports changes in interstitial glucose concentrations as they occur in the blood. Use of the CGMS minimizes animal contact and may be useful when performing a CGIT. Results obtained using a CGMS are useful for the evaluation of glucose responses during the evaluation of insulin sensitivity in equids. Seven mature, obese ponies. Ponies were equipped with CGMS for determination of interstitial glucose concentrations. Glucose (150 mg/kg, i.v.) and insulin (0.1 U/kg, i.v.) were administered and blood glucose concentrations determined at (minutes after time zero) 1, 5, 15, 25, 35, 45, 60, 75, 90, 105, and 120 with a hand-held glucometer. Blood chemistry results were compared with simultaneously obtained results using CGMS. Concordance coefficients determined for comparison of blood glucose concentrations determined by a hand-held glucometer and those determined by CGMS after the zero time point were 0.623, 0.764, 0.834, 0.854, and 0.818 (for delays of 0, 5, 10, 15, and 20 minutes, respectively). Interstitial glucose concentrations obtained by the CGMS compared favorably to blood glucose concentrations. CGMS may be useful for assessment of glucose dynamics in the CGIT. Copyright © 2010 by the American College of Veterinary Internal Medicine.

ABNORMAL FERTILIZATION IS RESPONSIBLE FOR REDUCED FECUNDITY FOLLOWING THIRAM-INDUCED OVULATORY DELAY IN THE RAT

EPA Science Inventory

Brief exposure to some pesticides, applied during a sensitive window for the neural regulation of ovulation, will block the preovulatory surge of LH, and thus delay ovulation. Previously, we have shown that a single i.p. injection of 50 mg/kg of thiram, a dithiocarbamate fungici...

Sensitivity of bandpass filters using recirculating delay-line structures

NASA Astrophysics Data System (ADS)

Heyde, Eric C.

1996-12-01

Recirculating delay lines have value notably as sensors and optical signal processors. Most useful applications depend on a high-finesse response from a network. A proof that, with given response parameters, more complex systems can produce behavior that is more stable to the effects of nonidealities than a single recirculating loop is presented.

Delayed ovulation and pregnancy outcome: effect ofenvironmental toxicants on the neuroendocrine control of theovary

EPA Science Inventory

In the female rat, we have shown that a burst exposure to environmental toxicants known to alter noradrenergic function will block the ovulatory surge of LH when administered during a sensitive period on the day of vaginal proestrus. Such treatments will delay ovulation by 24 h a...

Non-contact photoacoustic tomography and ultrasonography for brain imaging

NASA Astrophysics Data System (ADS)

Rousseau, Guy; Blouin, Alain; Monchalin, Jean-Pierre

2012-02-01

Photoacoustic tomography (PAT) and ultrasonography (US) of biological tissues usually rely on transducer arrays for the detection of ultrasound. Obtaining the best sensitivity requires a physical contact with the tissue using an intermediate coupling fluid (water or gel). This type of contact is a major drawback for several applications such as neurosurgery. Laser-ultrasonics is an established optical technique for the non-contact generation and detection of ultrasound in industrial materials. In this paper, the non-contact detection scheme used in laser-ultrasonics is adapted to allow probing of ultrasound in biological tissues while remaining below laser exposure safety limits. Both non-contact PAT (NCPAT) and non-contact US (NCUS) are demonstrated experimentally using a single-frequency detection laser emitting suitably shaped pulses and a confocal Fabry-Perot interferometer. It is shown that an acceptable sensitivity is obtained while remaining below the maximum permissible exposure (MPE) of biological tissues. Results obtained ex vivo with a calf brain specimen show that sub-mm endogenous and exogenous inclusions can be detected at depths exceeding 1 cm. When fully developed, the technique could be a unique diagnostic tool in neurosurgery providing deep imaging of blood vessels, blood clots and blood oxygenation.

Detection of coupling delay: A problem not yet solved

NASA Astrophysics Data System (ADS)

Coufal, David; Jakubík, Jozef; Jajcay, Nikola; Hlinka, Jaroslav; Krakovská, Anna; Paluš, Milan

2017-08-01

Nonparametric detection of coupling delay in unidirectionally and bidirectionally coupled nonlinear dynamical systems is examined. Both continuous and discrete-time systems are considered. Two methods of detection are assessed—the method based on conditional mutual information—the CMI method (also known as the transfer entropy method) and the method of convergent cross mapping—the CCM method. Computer simulations show that neither method is generally reliable in the detection of coupling delays. For continuous-time chaotic systems, the CMI method appears to be more sensitive and applicable in a broader range of coupling parameters than the CCM method. In the case of tested discrete-time dynamical systems, the CCM method has been found to be more sensitive, while the CMI method required much stronger coupling strength in order to bring correct results. However, when studied systems contain a strong oscillatory component in their dynamics, results of both methods become ambiguous. The presented study suggests that results of the tested algorithms should be interpreted with utmost care and the nonparametric detection of coupling delay, in general, is a problem not yet solved.

Sensitized phosphorescence of benzil-doped ladder-type methyl-poly(para-phenylene)

NASA Astrophysics Data System (ADS)

Bagnich, S. A.; Bässler, H.; Neher, D.

2004-11-01

The delayed luminescence and phosphorescence of ladder-type methyl-poly(para-phenylene) (MeLPPP) doped with benzil at a concentration of 20% by weight has been measured. The introduction of benzil leads to a dramatic reduction of the polymer singlet emission. At the same time, a new band with maximum at 611 nm appears, corresponding to the phosphorescence of MeLPPP. The phosphorescence decay on the short time scale is close to an exponential law with a time decay of 15 ms. This indicates that benzil can efficiently sensitize the phosphorescence of the polymer. In addition, a broad and featureless emission is observed in the delayed luminescence spectra of benzil-doped MeLPPP, which is attributed to an exciplex formed between the polymer host and the dopant. We further observe that the delayed fluorescence is enhanced by the addition of benzil. It is concluded that the delayed fluorescence of benzil-doped MeLPPP is mainly due to the annihilation of triplet excitons on the polymer. Finally, efficient triplet-triplet energy transfer from the benzil-doped polymer to the red-emitting phosphorescent dye Pt(II)octaethylporphyrin is established.

Pediatric "pet consort dermatitis"-Allergic contact dermatitis from transfer of bronopol from a pet cat.

PubMed

Hamann, Dathan; Ridpath, Alyson; Fernandez Faith, Esteban

2018-06-26

Consort dermatitis refers to an allergic contact dermatitis caused by transfer from an intimate contact to a sensitized patient. Although close contact with other humans most commonly provokes consort dermatitis, pets have been the source in a minority of cases. We present a unique case of transfer dermatitis from a patient's cat litter to her forearms. Pediatric dermatologists should be aware of the possibility of consort or "transfer" allergic contact dermatitis from pets. © 2018 Wiley Periodicals, Inc.

78 FR 68076 - Request for Information on Alternative Skin Sensitization Test Methods and Testing Strategies and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-13

... INFORMATION: Background: Allergic contact dermatitis (ACD), a skin reaction characterized by localized redness, swelling, blistering, or itching after direct contact with a skin allergen, is an important public health.... Web site: http://ntp.niehs.nih.gov/go/niceatm . FOR FURTHER INFORMATION CONTACT: Dr. Warren S. Casey...

Postural stabilization from fingertip contact II. Relationships between age, tactile sensibility and magnitude of contact forces.

PubMed

Tremblay, François; Mireault, Annie-Claude; Dessureault, Liam; Manning, Hélène; Sveistrup, Heidi

2005-07-01

In the present report, we extend our previous observations on the effect of age on postural stabilization from fingertip contact (Exp Brain Res 157 (2004) 275) to examine the possible influence of sensory thresholds measured at the fingertip on the magnitude of contact forces. Participants (young, n=25, 19-32 years; old, n=35, 60-86 years) underwent psychophysical testing of the right index finger to determine thresholds for spatial acuity, pressure sensitivity and kinesthetic acuity. Spatial acuity was determined from the ability to detect gaps of different widths, while Semmes-Weinstein monofilaments were used for pressure sensitivity. Kinesthetic acuity was determined by asking participants to discriminate plates of different thicknesses using a thumb-index precision grip. These tests were selected on the basis that each reflected different sensory coding mechanisms (resolution of spatial stimuli, detection of mechanical forces and integration of multi-sensory inputs for hand conformation) and thus provided specific information about the integrity and function of mechanoreceptive afferents innervating the hand. After log transformation, thresholds were first examined to determine the influence of age (young and old) and gender (male, female) on tactile acuity. Sensory thresholds were then entered into multiple linear regression models to examine their ability to predict fingertip contact forces (normal and tangential) applied to a smooth surface when subjects stood with eyes closed on either a firm or a compliant support surface. As expected, age exerted a significant effect (p<0.01) on all three thresholds, but its impact was greater on spatial acuity than on pressure sensitivity or kinesthetic acuity. Gender had a marginal impact on pressure sensitivity thresholds only. The regression analyses revealed that tactile thresholds determined at the index fingertip accounted for a substantial proportion of the variance (up to 30%) seen in the contact forces deployed on the touch-plate, especially those exerted in the normal direction. The same analyses further revealed that much of the variance explained by the models arose from inter-individual differences in tactile spatial acuity and not from differences in pressure sensitivity or in kinesthetic acuity. Thus, of all three tests, the spatial acuity task was the most sensitive at detecting differences in hand sensibility both within and between age groups and, accordingly, was also better at predicting the magnitude of fingertip forces deployed for postural stabilization. Since spatial acuity is critically dependent upon innervation density, we conclude that the degree of functional innervation at the fingertip was likely an important factor in determining the capacity of older participants to use contact cues for stability purposes, forcing the most affected individuals to exert unusually high pressures in order to achieve stabilization in the presence of reduced tactile inputs arising from contact with the touched surface.

Allergic contact hobby dermatitis from turpentine.

PubMed

Barchino-Ortiz, L; Cabeza-Martínez, R; Leis-Dosil, V M; Suárez-Fernández, R M; Lázaro-Ochaita, P

2008-01-01

Turpentine is an oleoresin obtained from various species of pine. It contains a volatile oil (oil of turpentine) which is responsible for its properties and this is the form generally used. Opportunity for contact with turpentine is widespread. It is universally used as a solvent to dissolve and thin lacquers, varnishes and paints. It is also an ingredient in many liniments and cold remedies. Turpentine is regarded as both a local irritant and a sensitizer. Cases of allergic contact dermatitis in painters, mechanics, shoe repairers and home decorators have been reported. We report a case of a non-professional painter who developed a contact allergic dermatitis due to his exposure to turpentine while doing oil-painting as a hobby. Dermatitis is one of the biggest dangers of working with art materials and occupational contact dermatitis is often detected on the hands of the painters. Solvents are indispensable and turpentine is the most important and the traditional one used in oil-painting. Contact allergy to oil of turpentine was reported to have become rare in Europe but over the last few years, increased rates of turpentine sensitization have been reported.

The effect of delay line on the performance of a fiber optic interferometric sensor

NASA Astrophysics Data System (ADS)

Lin, Yung-Li; Lin, Ken-Huang; Lin, Wuu-Wen; Chen, Mao-Hsiung

2007-09-01

The optical fiber has the features of low loss and wide bandwidth; it has replaced the coaxial cable as the mainstream of the communication system in recent years. Because of its high sensitivity characteristic, the interferometer is usually applied to long distance, weak signal detection. In general, if the area to be monitored is located far away, the weak signal will make it uneasy to detect. An interferometer is used for phase detection. Thus, the hydrophone which is based on interferometric fiber optic sensor has extremely high sensitivity. Sagnac interferometric hydrophone has low noise of marine environment, which is more suitably used to detect underwater acoustic signal than that of a Mach-Zehnder interferometer. In this paper, we propose the configuration of dual Sagnac interferometer, and use the mathematical methods to drive and design optimal two delay fiber lengths, which can enlarge the dynamic range of underwater acoustic detection. In addition, we also use software simulation to design optimal two delay fiber lengths. The experimental configuration of dual Sagnac interferometer with two optical delay line is shown as Fig. 1. The maximum and minimum measurable phase signal value of dual Sagnac interferometer (L II=2 km, L 4=222.2 m), shown in Fig. 3. The fiber optic sensor head is of mandrel type. The acoustic window is made of silicon rubbers. It was shown that we can increase their sensitivities by increasing number of wrapping fiber coils. In our experiment, the result shows that among all the mandrel sensor heads, the highest dynamic range is up to 37.6 +/- 1.4 dB, and its sensitivity is -223.3 +/-1.7 dB re V / 1μ Pa. As for the configuration of the optical interferometers, the intensity of the dual Sagnac interferometer is 20 dB larger than its Sagnac counterpart. Its dynamic range is above 66 dB where the frequency ranges is between 50 ~ 400 Hz, which is 24 dB larger than that of the Sagnac interferometer with the sensitivity of -192.0 dB re V / l μPa. In addition, by using software simulation to design optimal lengths of delay fibers, we can increase the dynamic range of interferometer on underwater acoustic detection. This paper verifies that, by means of adjusting the length of these two delay fibers, we can actually increase the dynamic range of acoustic signal detection.

Contemporary Determinants of Delayed Benchmark Timelines in Acute Myocardial Infarction in Men and Women.

PubMed

Alnsasra, Hilmi; Zahger, Doron; Geva, Diklah; Matetzky, Shlomi; Beigel, Roy; Iakobishvili, Zaza; Alcalai, Ronny; Atar, Shaul; Shimony, Avi

2017-11-15

Treatment delays in patients with acute myocardial infarction (AMI) are related to increased morbidity and mortality. Hence, identifying determinants of delay may help reduce time to treatment. Importantly, limited data suggest that there may be sex-related disparities in benchmark timelines. Although guidelines advocate the use of the first medical contact (FMC) rather than hospital admission as the moment from which delays to treatment should be monitored, the latter is still often used for quality purposes. We aimed to identify factors associated with treatment delays, with an emphasis on sex-related disparities. We reviewed data on 3,658 patients with AMI from 2 contemporary, consecutive multicenter surveys. Measured delays were FMC-to-electrocardiogram >10 minutes in ST-elevation MI (STEMI) and non-STEMI, FMC-to-primary percutaneous coronary intervention >90 minutes in STEMI, and invasive angiography >72 hours after admission in non-STEMI patients. Timely electrocardiogram was performed in 48% of patients with STEMI and in 39.8% of non-STEMI patients without significant sex-related differences. Independent determinants of delay included atypical chest pain (CP) and presentation during daytime. In patients with STEMI, 37.5% had primary percutaneous coronary intervention in less than 90 minutes without significant sex-related disparities. Independent determinants of delay included atypical CP, night presentation, and diabetes. In non-STEMI patients, independent determinants of delayed invasive approach were female sex, age >75 years, atypical CP, and renal failure. In conclusion, significant treatment delays in patients with AMI are still frequent in contemporary practice, highlighting the need for improvement and guidelines implementation. Predictors of delay identified in our study may facilitate targeting of interventions to improve adherence to guidelines. Copyright © 2017 Elsevier Inc. All rights reserved.

Battlefield Acquired Immunogenicity to Metals Affects Orthopaedic Implant Outcome

DTIC Science & Technology

2014-10-01

consumer products: a role in allergic contact dermatitis ? Contact Dermatitis 1993;28:15-25. (13) Cramers M, Lucht U. Metal sensitivity in patients... dermatitis presumably due to metallic foreign bodies containing nickel or cobalt. Current Contact News 1977;19:285-95. (15) Benson MK, Goodwin PG...Sipilainen-Malm T, Estlander T, Zitting A, Jolanki R, Tarvainen K. Nickel release from metals, and a case of allergic contact dermatitis from

Image encryption based on a delayed fractional-order chaotic logistic system

NASA Astrophysics Data System (ADS)

Wang, Zhen; Huang, Xia; Li, Ning; Song, Xiao-Na

2012-05-01

A new image encryption scheme is proposed based on a delayed fractional-order chaotic logistic system. In the process of generating a key stream, the time-varying delay and fractional derivative are embedded in the proposed scheme to improve the security. Such a scheme is described in detail with security analyses including correlation analysis, information entropy analysis, run statistic analysis, mean-variance gray value analysis, and key sensitivity analysis. Experimental results show that the newly proposed image encryption scheme possesses high security.

Investigation of e-beam sensitive negative-tone chemically amplified resists for binary mask making

NASA Astrophysics Data System (ADS)

Irmscher, Mathias; Berger, Lothar; Beyer, Dirk; Butschke, Joerg; Dress, Peter; Hoffmann, Thomas; Hudek, Peter; Koepernik, Corinna; Tschinkl, Martin; Voehringer, Peter

2003-08-01

Negative-tone chemically amplified resists MES-EN1G (JSR), FEN-270 (Fujifilm ARCH), EN-024M (TOK) and NEB-22 (Sumitomo) were evaluated for binary mask making. The investigations were performed on an advanced tool set comprising a 50kV e-beam writer Leica SB350, a Steag Hamatech hot/cool plate module APB5000, a Steag Hamatech developer ASP5000, an UNAXIS MASK ETCHER III and a SEM LEO1560 with integrated CD measurement option. We investigated and compared the evaluated resists in terms of resolution, e-beam sensitivity, resist profile, post exposure bake sensitivity, CD-uniformity, line edge roughness, pattern fidelity and etch resistance. Furthermore, the influence of post coating delay and post exposure delay in vacuum and air was determined.

Combined in vivo and in vitro approach for the characterization of penicillin-specific polyclonal lymphocyte reactivity: tolerance tests with safe penicillins instead of challenge with culprit drugs.

PubMed

Sachs, B; Al Masaoudi, T; Merk, H F; Erdmann, S

2004-10-01

Amino-penicillins are a major cause of delayed-type reactions to penicillins. The aim of this study was to establish a diagnostic approach for the characterization of the individual penicillin-specific polyclonal lymphocyte reactivity in order to detect side chain-specific sensitization to amino-penicillins. Patients can then be advised to undergo a tolerance test with safe penicillins instead of provocation with culprit penicillins for confirmation of penicillin allergy. We investigated penicillin-specific polyclonal lymphocyte reactivity in nine patients with delayed-type reactions to amino-penicillins by a combined in vivo (patch, prick and intracutaneous tests with delayed readings) and in vitro (lymphocyte transformation test, LTT) approach. A combination of LTT and skin tests improved the sensitivity for the characterization of penicillin-specific polyclonal lymphocyte reactivity and allowed the detection of three different patterns of lymphocyte reactivity. Four patients showed a side chain-specific sensitization to amino-penicillins in vivo and in vitro and were advised to undergo tolerance tests with safe penicillins. Two patients agreed and were exposed to parenteral benzyl-penicillin and oral phenoxymethyl-penicillin which they tolerated without complications. These data suggest that a combined in vivo and in vitro approach is helpful for the detection of side chain-specific sensitization to amino-penicillins. Patients with such sensitization are very likely to tolerate safe penicillins, thereby expanding their therapeutic options when antibiotic treatment is required.

Linear stability and nonlinear analyses of traffic waves for the general nonlinear car-following model with multi-time delays

NASA Astrophysics Data System (ADS)

Sun, Dihua; Chen, Dong; Zhao, Min; Liu, Weining; Zheng, Linjiang

2018-07-01

In this paper, the general nonlinear car-following model with multi-time delays is investigated in order to describe the reactions of vehicle to driving behavior. Platoon stability and string stability criteria are obtained for the general nonlinear car-following model. Burgers equation and Korteweg de Vries (KdV) equation and their solitary wave solutions are derived adopting the reductive perturbation method. We investigate the properties of typical optimal velocity model using both analytic and numerical methods, which estimates the impact of delays about the evolution of traffic congestion. The numerical results show that time delays in sensing relative movement is more sensitive to the stability of traffic flow than time delays in sensing host motion.

Moderate psychosocial stress appears not to impair recall of words learned 4 weeks prior to stress exposure.

PubMed

Wolf, Oliver T; Schommer, Nicole C; Hellhammer, Dirk H; Reischies, Friedel M; Kirschbaum, Clemens

2002-02-01

Recent studies in humans have reported that recall of previously learned material is especially sensitive to the disruptive effects of pharmacologically induced cortisol elevations. Whether similar effects occur after exposure to psychosocial stress remains to be shown. Moreover it is unknown whether stress before or after the initial learning interacts with the later effects of repeated stress on delayed recall (e.g. state-dependent learning). Forty subjects participated in the present experiment. They learned a word list either one hour before or 10 min after exposure to a psychosocial laboratory stressor. Delayed recall was tested 4 weeks later, again either before or after stress. Salivary cortisol levels increased significantly in response to both stress exposures. Stress had no effects on the initial learning and also did not impair delayed recall. Moreover there was no evidence for state-dependent learning. The current data seem to be in conflict with previous studies demonstrating that delayed recall is especially sensitive to elevated cortisol levels. Several reasons for these discrepancies are discussed. Among them is the small sample size, the moderate cortisol increase in response to the second stress exposure but also the long recall delay, which might lead to memory traces less susceptible to stress.

Simulation and characterization of a laterally-driven inertial micro-switch

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

Chen, Wenguo; Wang, Yang; Wang, Huiying

2015-04-15

A laterally-driven inertial micro-switch was designed and fabricated using surface micromachining technology. The dynamic response process was simulated by ANSYS software, which revealed the vibration process of movable electrode when the proof mass is shocked by acceleration in sensitive direction. The test results of fabricated inertial micro-switches with and without anti-shock beams indicated that the contact process of micro-switch with anti-shock beams is more reliable than the one without anti-shock beams. The test results indicated that three contact signals had been observed in the contact process of the inertial switch without anti-shock beams, and only one contact signal in themore » inertial switch with anti-shock beams, which demonstrated that the anti-shock beams can effectively constrain the vibration in non-sensitive direction.« less

Recommendation to increase the test concentration of methylchloroisothiazolinone/methylisothiazolinone in the European baseline patch test series - on behalf of the European Society of Contact Dermatitis and the European Environmental and Contact Dermatitis Research Group.

PubMed

Bruze, Magnus; Goossens, An; Isaksson, Marléne

2014-07-01

Methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) in aqua is present in the European baseline patch test series at 100 ppm, whereas 200 ppm has been used in Sweden since 1986, in Spain in the late 1980s, and, in recent years, also in the United Kingdom and Ireland. With regard to MCI/MI, to investigate the data on contact allergy rates in dermatitis patients, the frequencies of allergic contact dermatitis in the same group, and adverse reactions, particularly patch test sensitization in tested dermatitis patients, and to find the optimal patch test concentration as dose in mg/cm(2) . We performed a survey of the literature found via the National Library of Medicine (PubMed, http://www.ncbi.nlm.nih.gov/pubmed, last accessed 20 February 2014). MCI/MI at 200 ppm aq. diagnosis substantially more contact allergy and allergic contact dermatitis, without any registered increase in patch test sensitization, than the presently used concentration of 100 ppm. MCI/MI at 200 ppm aq. is recommended to be included in the European baseline patch test series. To avoid patch test sensitization, a dose of 0.006 mg/cm(2) must not be exceeded, which means a volume of 15 µl for Finn Chambers(®) (Ø 8 mm). © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Delay discounting as emotional processing: an electrophysiological study.

PubMed

Blackburn, Marianna; Mason, Liam; Hoeksma, Marco; Zandstra, Elizabeth H; El-Deredy, Wael

2012-01-01

Both theoretical models and functional imaging studies implicate the involvement of emotions within the delay discounting process. However, defining this role has been difficult to establish with neuroimaging techniques given the automaticity of emotional responses. To address this, the current study examined electrophysiological correlates involved in the detection and evaluation of immediate and delayed monetary outcomes. Our results showed that modulation of both early and later ERP components previously associated with affective stimuli processing are sensitive to the signalling of delayed rewards. Together with behavioural reaction times that favoured immediacy, we demonstrated, for the first time, that time delays modify the incentive value of monetary rewards via mechanisms of emotional bias and selective visual attention. Furthermore, our data are consistent with the hypothesis that delayed and thus intangible rewards are perceived less saliently, and rely on emotion as a common currency within decision making. This study provides a new approach to delay discounting and highlights a potential novel route through which delay discounting may be investigated.

Behavioral effects of delayed timeouts from reinforcement.

PubMed

Byrne, Tom; Poling, Alan

2017-03-01

Timeouts are sometimes used in applied settings to reduce target responses, and in some circumstances delays are unavoidably imposed between the onset of a timeout and the offset of the response that produces it. The present study examined the effects of signaled and unsignaled timeouts in rats exposed to concurrent fixed-ratio 1 fixed-ratio 1 schedules of food delivery, where each response on one lever, the location of which changed across conditions, produced both food and a delayed 10-s timeout. Delays of 0 to 38 s were examined. Delayed timeouts often, but not always, substantially reduced the number of responses emitted on the lever that produced timeouts relative to the number emitted on the lever that did not produce timeouts. In general, greater sensitivity was observed to delayed timeouts when they were signaled. These results demonstrate that delayed timeouts, like other delayed consequences, can affect behavior, albeit less strongly than immediate consequences. © 2017 Society for the Experimental Analysis of Behavior.

Pupillometric and saccadic measures of affective and executive processing in anxiety.

PubMed

Hepsomali, Piril; Hadwin, Julie A; Liversedge, Simon P; Garner, Matthew

2017-07-01

Anxious individuals report hyper-arousal and sensitivity to environmental stimuli, difficulties concentrating, performing tasks efficiently and inhibiting unwanted thoughts and distraction. We used pupillometry and eye-movement measures to compare high vs. low anxious individuals hyper-reactivity to emotional stimuli (facial expressions) and subsequent attentional biases in a memory-guided pro- and antisaccade task during conditions of low and high cognitive load (short vs. long delay). High anxious individuals produced larger and slower pupillary responses to face stimuli, and more erroneous eye-movements, particularly following long delay. Low anxious individuals' pupillary responses were sensitive to task demand (reduced during short delay), whereas high anxious individuals' were not. These findings provide evidence in anxiety of enhanced, sustained and inflexible patterns of pupil responding during affective stimulus processing and cognitive load that precede deficits in task performance. Copyright © 2017. Published by Elsevier B.V.

Design, fabrication and metrological evaluation of wearable pressure sensors.

PubMed

Goy, C B; Menichetti, V; Yanicelli, L M; Lucero, J B; López, M A Gómez; Parodi, N F; Herrera, M C

2015-04-01

Pressure sensors are valuable transducers that are necessary in a huge number of medical application. However, the state of the art of compact and lightweight pressure sensors with the capability of measuring the contact pressure between two surfaces (contact pressure sensors) is very poor. In this work, several types of wearable contact pressure sensors are fabricated using different conductive textile materials and piezo-resistive films. The fabricated sensors differ in size, the textile conductor used and/or the number of layers of the sandwiched piezo-resistive film. The intention is to study, through the obtaining of their calibration curves, their metrological properties (repeatability, sensitivity and range) and determine which physical characteristics improve their ability for measuring contact pressures. It has been found that it is possible to obtain wearable contact pressure sensors through the proposed fabrication process with satisfactory repeatability, range and sensitivity; and that some of these properties can be improved by the physical characteristics of the sensors.

Optical critical dimension metrology for directed self-assembly assisted contact hole shrink

NASA Astrophysics Data System (ADS)

Dixit, Dhairya; Green, Avery; Hosler, Erik R.; Kamineni, Vimal; Preil, Moshe E.; Keller, Nick; Race, Joseph; Chun, Jun Sung; O'Sullivan, Michael; Khare, Prasanna; Montgomery, Warren; Diebold, Alain C.

2016-01-01

Directed self-assembly (DSA) is a potential patterning solution for future generations of integrated circuits. Its main advantages are high pattern resolution (˜10 nm), high throughput, no requirement of high-resolution mask, and compatibility with standard fab-equipment and processes. The application of Mueller matrix (MM) spectroscopic ellipsometry-based scatterometry to optically characterize DSA patterned contact hole structures fabricated with phase-separated polystyrene-b-polymethylmethacrylate (PS-b-PMMA) is described. A regression-based approach is used to calculate the guide critical dimension (CD), DSA CD, height of the PS column, thicknesses of underlying layers, and contact edge roughness of the post PMMA etch DSA contact hole sample. Scanning electron microscopy and imaging analysis is conducted as a comparative metric for scatterometry. In addition, optical model-based simulations are used to investigate MM elements' sensitivity to various DSA-based contact hole structures, predict sensitivity to dimensional changes, and its limits to characterize DSA-induced defects, such as hole placement inaccuracy, missing vias, and profile inaccuracy of the PMMA cylinder.

Patient perspectives of care in a regionalised trauma system: lessons from the Victorian State Trauma System.

PubMed

Gabbe, Belinda J; Sleney, Jude S; Gosling, Cameron M; Wilson, Krystle; Hart, Melissa J; Sutherland, Ann M; Christie, Nicola

2013-02-18

To explore injured patients' experiences of trauma care to identify areas for improvement in service delivery. Qualitative study using in-depth, semi-structured interviews, conducted from 1 April 2011 to 31 January 2012, with 120 trauma patients registered by the Victorian State Trauma Registry and the Victorian Orthopaedic Trauma Outcomes Registry and managed at the major adult trauma services (MTS) in Victoria. Emergent themes from patients' experiences of acute, rehabilitation and post-discharge care in the Victorian State Trauma System (VSTS). Patients perceived their acute hospital care as high quality, although 3s with communication and surgical management delays were common. Discharge from hospital was perceived as stressful, and many felt ill prepared for discharge. A consistent emerging theme was the sense of a lack of coordination of post-discharge care, and the absence of a consistent point of contact for ongoing management. Most patients' primary point of contact after discharge was outpatient clinics at the MTS, which were widely criticised because of substantial delays in receiving an appointment, prolonged waiting times, limited time with clinicians, lack of continuity of care and inability to see senior clinicians. This study highlights perceived 3s in the patient care pathway in the VSTS, especially those relating to communication, information provision and post-discharge care. Trauma patients perceived the need for a single point of contact for coordination of post-discharge care.

Detecting delay in visual feedback of an action as a monitor of self recognition.

PubMed

Hoover, Adria E N; Harris, Laurence R

2012-10-01

How do we distinguish "self" from "other"? The correlation between willing an action and seeing it occur is an important cue. We exploited the fact that this correlation needs to occur within a restricted temporal window in order to obtain a quantitative assessment of when a body part is identified as "self". We measured the threshold and sensitivity (d') for detecting a delay between movements of the finger (of both the dominant and non-dominant hands) and visual feedback as seen from four visual perspectives (the natural view, and mirror-reversed and/or inverted views). Each trial consisted of one presentation with minimum delay and another with a delay of between 33 and 150 ms. Participants indicated which presentation contained the delayed view. We varied the amount of efference copy available for this task by comparing performances for discrete movements and continuous movements. Discrete movements are associated with a stronger efference copy. Sensitivity to detect asynchrony between visual and proprioceptive information was significantly higher when movements were viewed from a "plausible" self perspective compared with when the view was reversed or inverted. Further, we found differences in performance between dominant and non-dominant hand finger movements across the continuous and single movements. Performance varied with the viewpoint from which the visual feedback was presented and on the efferent component such that optimal performance was obtained when the presentation was in the normal natural orientation and clear efferent information was available. Variations in sensitivity to visual/non-visual temporal incongruence with the viewpoint in which a movement is seen may help determine the arrangement of the underlying visual representation of the body.

Contact allergy to a contaminant in Kathon CG in the guinea pig.

PubMed

Bruze, M; Gruvberger, B; Persson, K

1987-01-01

Kathon CG is a commercial preservative, consisting of the two active ingredients, 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one (5243-K-CG) and other components. 4,5-dichloro-2-methyl-4-isothiazolin-3-one (45243-K-CG) is a contaminant in Kathon CG. The chemically related active ingredients are known to be contact sensitizers in humans and guinea pigs. Aims of this study were to determine the sensitizing capacity of this contaminant and also to investigate the cross-reaction pattern by guinea pig sensitization tests. 45243-K-CG was demonstrated to be a strong sensitizer; all animals reacting to 45243-K-CG also reacted to 5243-K-CG when rechallenged.

Accuracy of different diagnostic tests for early, delayed and late prosthetic joint infection.

PubMed

Fernández-Sampedro, M; Fariñas-Alvarez, C; Garces-Zarzalejo, C; Alonso-Aguirre, M A; Salas-Venero, C; Martínez-Martínez, L; Fariñas, M C

2017-08-25

A combination of laboratory, histopathological and microbiological tests for diagnosis of prosthetic joint infection (PJI) have been strongly recommended. This study aims to characterize the accuracy of individual or group tests, such as culture of sonicate fluid, synovial fluid and peri-implant tissue, C-reactive protein (CRP) and histopathology for detection of early, delayed and late PJI. A prospective study of patients undergoing hip or knee arthroplasty from February 2009 to February 2014 was performed in a Spanish tertiary health care hospital. The diagnostic accuracy of the different methods was evaluated constructing receiver-operating-characteristic (ROC) curve areas. One hundred thirty consecutive patients were included: 18 (13.8%) early PJI, 35 (27%) delayed PJI and 77 (59.2%) late PJI. For individual parameters, the area under the ROC curve for peri-implant tissue culture was larger for early (0.917) than for delayed (0.829) and late PJI (0.778), p = 0.033. There was a significantly larger difference for ROC area in the synovial fluid culture for delayed (0.803) than for early (0.781) and late infections (0.679), p = 0.039. The comparison of the areas under the ROC curves for the two microbiological tests showed that sonicate fluid was significantly different from peri-implant tissue in delayed (0.951 vs 0.829, p = 0.005) and late PJI (0.901 vs 0.778, p = 0.000). The conjunction of preoperative parameters, synovial fluid culture and CRP, improved the accuracy for late PJI (p = 0.01). The conjunction of histopathology and sonicate fluid culture increased the area under ROC curve of sonication in early (0.917 vs 1.000); p = 0.06 and late cases (0.901 vs 0.999); p < 0.001. For early PJI, sonicate fluid and peri-implant tissue cultures achieve the same best sensitivity. For delayed and late PJI, sonicate fluid culture is the most sensitive individual diagnostic method. By combining histopathology and peri-implant tissue, all early, 97% of delayed and 94.8% of late cases are diagnosed. The conjunction of histopathology and sonicate fluid culture yields a sensitivity of 100% for all types of infection.

Cyclopentolate Ophthalmic

MedlinePlus

... e.g., use sunglasses). Cyclopentolate may make your eyes sensitive to sunlight.you should know that ophthalmic cyclopentolate contains benzalkonium chloride, which can be absorbed by soft contact lenses. If you wear contact lenses, remove them before instilling ophthalmic cyclopentolate.

77 FR 30855 - Sixty-Ninth Report of the TSCA Interagency Testing Committee to the Administrator of the...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-23

... diisocyanates can cause contact dermatitis, skin and respiratory tract irritation, immune sensitization, and... identity or contact information unless you provide it in the body of your comment. If you send an email... Internet. If you submit an electronic comment, EPA recommends that you include your name and other contact...

Haloperidol and Rimonabant Increase Delay Discounting in Rats Fed High-Fat and Standard-Chow Diets

PubMed Central

Boomhower, Steven R.; Rasmussen, Erin B.

2016-01-01

The dopamine and endocannabinoid neurotransmitter systems have been implicated in delay discounting, a measure of impulsive choice, and obesity. The current study was designed to determine the extent to which haloperidol and rimonabant affected delay discounting in rats fed standard-chow and high-fat diets. Sprague-Dawley rats were allowed to free-feed under a high-fat diet (4.73 kcal/g) or a standard-chow diet (3.0 kcal/g) for three months. Then, operant sessions began in which rats (n = 9 standard chow; n = 10 high-fat) chose between one sucrose pellet delivered immediately vs. three sucrose pellets after a series of delays. In another condition, carrot-flavored pellets replaced sucrose pellets. After behavior stabilized, acute injections of rimonabant (0.3-10 mg/kg) and haloperidol (0.003-0.1 mg/kg) were administered i.p. before some choice sessions in both pellet conditions. Haloperidol and rimonabant increased discounting in both groups of rats by decreasing percent choice for the larger reinforcer and area-under-the-curve (AUC) values. Rats in the high-fat diet condition demonstrated increased sensitivity to haloperidol compared to chow-fed controls: haloperidol increased discounting in both dietary groups in the sucrose condition,, but only in the high-fat-fed rats in the carrot-pellet condition. These findings indicate that blocking D2 and CB1 receptors results in increased delay discounting, and that a high-fat diet may alter sensitivity to dopaminergic compounds using the delay-discounting task. PMID:25000488

Unequal-Arm Interferometry and Ranging in Space

NASA Technical Reports Server (NTRS)

Tinto, Massimo

2005-01-01

Space-borne interferometric gravitational wave detectors, sensitive in the low-frequency (millihertz) band, will fly in the next decade. In these detectors the spacecraft-to-spacecraft light-traveltimes will necessarily be unequal, time-varying, and (due to aberration) have different time delays on up- and down-links. By using knowledge of the inter-spacecraft light-travel-times and their time evolution it is possible to cancel in post-processing the otherwise dominant laser phase noise and obtain a variety of interferometric data combinations sensitive to gravitational radiation. This technique, which has been named Time-Delay Interferometry (TDI), can be implemented with constellations of three or more formation-flying spacecraft that coherently track each other. As an example application we consider the Laser Interferometer Space Antenna (LISA) mission and show that TDI combinations can be synthesized by properly time-shifting and linearly combining the phase measurements performed on board the three spacecraft. Since TDI exactly suppresses the laser noises when the delays coincide with the light-travel-times, we then show that TDI can also be used for estimating the time-delays needed for its implementation. This is done by performing a post-processing non-linear minimization procedure, which provides an effective, powerful, and simple way for making measurements of the inter-spacecraft light-travel-times. This processing technique, named Time-Delay Interferometric Ranging (TDIR), is highly accurate in estimating the time-delays and allows TDI to be successfully implemented without the need of a dedicated ranging subsystem.

Resonant characteristics and sensitivity dependency on the contact surface in QCM-micropillar-based system of coupled resonator sensors

NASA Astrophysics Data System (ADS)

Kashan, M. A. M.; Kalavally, V.; Lee, H. W.; Ramakrishnan, N.

2016-05-01

We report the characteristics and sensitivity dependence over the contact surface in coupled resonating sensors (CRSs) made of high aspect ratio resonant micropillars attached to a quartz crystal microbalance (QCM). Through experiments and simulation, we observed that when the pillars of resonant heights were placed in maximum displacement regions the resonance frequency of the QCM increased following the coupled resonance characteristics, as the pillar offered elastic loading to the QCM surface. However, the same pillars when placed in relatively lower displacement regions, in spite of their resonant dimension, offered inertial loading and resulted in a decrease in QCM resonance frequency, as the displacement amplitude was insufficient to couple the vibrations from the QCM to the pillars. Accordingly, we discovered that the coupled resonance characteristics not only depend on the resonant structure dimensions but also on the contact regions in the acoustic device. Further analysis revealed that acoustic pressure at the contact surface also influences the resonance frequency characteristics and sensitivity of the CRS. To demonstrate the significance of the present finding for sensing applications, humidity sensing is considered as the example measurand. When a sensing medium made of resonant SU-8 pillars was placed in a maximum displacement region on a QCM surface, the sensitivity increased by 14 times in comparison to a resonant sensing medium placed in a lower displacement region of a QCM surface.

Many States unprepared for 'Y2K' computer woes.

PubMed

1998-12-25

Most computer systems that States use to process health benefits are not Y2K compliant, which could jeopardize Medicaid application processing. This could cause recipients to lose benefits or experience delays in payments. Only seven states have reported that their systems are ready for the year 2000. Contact information is provided.

77 FR 21155 - Open Meeting of the Taxpayer Advocacy Panel Return Processing Delays Project Committee

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-09

... 4:30 p.m. and Friday, June 1st from 8 a.m. to 12:00 noon Pacific Time at TAP Office, 915 2nd Avenue... more information please contact Ms. Spinks at 1-888-912-1227 or 206-220-6098, or write TAP Office, 915...

The emergence of polychronization and feature binding in a spiking neural network model of the primate ventral visual system.

PubMed

Eguchi, Akihiro; Isbister, James B; Ahmad, Nasir; Stringer, Simon

2018-07-01

We present a hierarchical neural network model, in which subpopulations of neurons develop fixed and regularly repeating temporal chains of spikes (polychronization), which respond specifically to randomized Poisson spike trains representing the input training images. The performance is improved by including top-down and lateral synaptic connections, as well as introducing multiple synaptic contacts between each pair of pre- and postsynaptic neurons, with different synaptic contacts having different axonal delays. Spike-timing-dependent plasticity thus allows the model to select the most effective axonal transmission delay between neurons. Furthermore, neurons representing the binding relationship between low-level and high-level visual features emerge through visually guided learning. This begins to provide a way forward to solving the classic feature binding problem in visual neuroscience and leads to a new hypothesis concerning how information about visual features at every spatial scale may be projected upward through successive neuronal layers. We name this hypothetical upward projection of information the "holographic principle." (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Motor Asymmetry and Substantia Nigra Volume Are Related to Spatial Delayed Response Performance in Parkinson Disease

ERIC Educational Resources Information Center

Foster, Erin R.; Black, Kevin J.; Antenor-Dorsey, Jo Ann V.; Perlmutter, Joel S.; Hershey, Tamara

2008-01-01

Studies suggest motor deficit asymmetry may help predict the pattern of cognitive impairment in individuals with Parkinson disease (PD). We tested this hypothesis using a highly validated and sensitive spatial memory task, spatial delayed response (SDR), and clinical and neuroimaging measures of PD asymmetry. We predicted SDR performance would be…

Comparison of MRI-based estimates of articular cartilage contact area in the tibiofemoral joint.

PubMed

Henderson, Christopher E; Higginson, Jill S; Barrance, Peter J

2011-01-01

Knee osteoarthritis (OA) detrimentally impacts the lives of millions of older Americans through pain and decreased functional ability. Unfortunately, the pathomechanics and associated deviations from joint homeostasis that OA patients experience are not well understood. Alterations in mechanical stress in the knee joint may play an essential role in OA; however, existing literature in this area is limited. The purpose of this study was to evaluate the ability of an existing magnetic resonance imaging (MRI)-based modeling method to estimate articular cartilage contact area in vivo. Imaging data of both knees were collected on a single subject with no history of knee pathology at three knee flexion angles. Intra-observer reliability and sensitivity studies were also performed to determine the role of operator-influenced elements of the data processing on the results. The method's articular cartilage contact area estimates were compared with existing contact area estimates in the literature. The method demonstrated an intra-observer reliability of 0.95 when assessed using Pearson's correlation coefficient and was found to be most sensitive to changes in the cartilage tracings on the peripheries of the compartment. The articular cartilage contact area estimates at full extension were similar to those reported in the literature. The relationships between tibiofemoral articular cartilage contact area and knee flexion were also qualitatively and quantitatively similar to those previously reported. The MRI-based knee modeling method was found to have high intra-observer reliability, sensitivity to peripheral articular cartilage tracings, and agreeability with previous investigations when using data from a single healthy adult. Future studies will implement this modeling method to investigate the role that mechanical stress may play in progression of knee OA through estimation of articular cartilage contact area.

Dual sensitivity of inferior colliculus neurons to ITD in the envelopes of high-frequency sounds: experimental and modeling study

PubMed Central

Wang, Le; Devore, Sasha; Delgutte, Bertrand

2013-01-01

Human listeners are sensitive to interaural time differences (ITDs) in the envelopes of sounds, which can serve as a cue for sound localization. Many high-frequency neurons in the mammalian inferior colliculus (IC) are sensitive to envelope-ITDs of sinusoidally amplitude-modulated (SAM) sounds. Typically, envelope-ITD-sensitive IC neurons exhibit either peak-type sensitivity, discharging maximally at the same delay across frequencies, or trough-type sensitivity, discharging minimally at the same delay across frequencies, consistent with responses observed at the primary site of binaural interaction in the medial and lateral superior olives (MSO and LSO), respectively. However, some high-frequency IC neurons exhibit dual types of envelope-ITD sensitivity in their responses to SAM tones, that is, they exhibit peak-type sensitivity at some modulation frequencies and trough-type sensitivity at other frequencies. Here we show that high-frequency IC neurons in the unanesthetized rabbit can also exhibit dual types of envelope-ITD sensitivity in their responses to SAM noise. Such complex responses to SAM stimuli could be achieved by convergent inputs from MSO and LSO onto single IC neurons. We test this hypothesis by implementing a physiologically explicit, computational model of the binaural pathway. Specifically, we examined envelope-ITD sensitivity of a simple model IC neuron that receives convergent inputs from MSO and LSO model neurons. We show that dual envelope-ITD sensitivity emerges in the IC when convergent MSO and LSO inputs are differentially tuned for modulation frequency. PMID:24155013

Visuomotor sensitivity to visual information about surface orientation.

PubMed

Knill, David C; Kersten, Daniel

2004-03-01

We measured human visuomotor sensitivity to visual information about three-dimensional surface orientation by analyzing movements made to place an object on a slanted surface. We applied linear discriminant analysis to the kinematics of subjects' movements to surfaces with differing slants (angle away form the fronto-parallel) to derive visuomotor d's for discriminating surfaces differing in slant by 5 degrees. Subjects' visuomotor sensitivity to information about surface orientation was very high, with discrimination "thresholds" ranging from 2 to 3 degrees. In a first experiment, we found that subjects performed only slightly better using binocular cues alone than monocular texture cues and that they showed only weak evidence for combining the cues when both were available, suggesting that monocular cues can be just as effective in guiding motor behavior in depth as binocular cues. In a second experiment, we measured subjects' perceptual discrimination and visuomotor thresholds in equivalent stimulus conditions to decompose visuomotor sensitivity into perceptual and motor components. Subjects' visuomotor thresholds were found to be slightly greater than their perceptual thresholds for a range of memory delays, from 1 to 3 s. The data were consistent with a model in which perceptual noise increases with increasing delay between stimulus presentation and movement initiation, but motor noise remains constant. This result suggests that visuomotor and perceptual systems rely on the same visual estimates of surface slant for memory delays ranging from 1 to 3 s.

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.

Timing of food introduction and development of food sensitization in a prospective birth cohort.

PubMed

Tran, Maxwell M; Lefebvre, Diana L; Dai, David; Dharma, Christoffer; Subbarao, Padmaja; Lou, Wendy; Azad, Meghan B; Becker, Allan B; Mandhane, Piush J; Turvey, Stuart E; Sears, Malcolm R

2017-08-01

The effect of infant feeding practices on the development of food allergy remains controversial. We examined the relationship between timing and patterns of food introduction and sensitization to foods at age 1 year in the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort study. Nutrition questionnaire data prospectively collected at age 3, 6, 12, 18, and 24 months were used to determine timing of introduction of cow's milk products, egg, and peanut. At age 1 year, infants underwent skin prick testing to cow's milk, egg white, and peanut. Logistic regression models were fitted to assess the impact of timing of food exposures on sensitization outcomes, and latent class analysis was used to study patterns of food introduction within the cohort. Among 2124 children with sufficient data, delaying introduction of cow's milk products, egg, and peanut beyond the first year of life significantly increased the odds of sensitization to that food (cow's milk adjOR 3.69, 95% CI 1.37-9.08; egg adjOR 1.89, 95% CI 1.25-2.80; peanut adjOR 1.76, 95% CI 1.07-3.01). Latent class analysis produced a three-class model: early, usual, and delayed introduction. A pattern of delayed introduction, characterized by avoidance of egg and peanut during the first year of life, increased the odds of sensitization to any of the three tested foods (adjOR 1.78, 95% CI 1.26-2.49). Avoidance of potentially allergenic foods during the first year of life significantly increased the odds of sensitization to the corresponding foods. © 2017 The Authors. Pediatric Allergy and Immunology Published by John Wiley & Sons Ltd.

Logistics of community smallpox control through contact tracing and ring vaccination: a stochastic network model.

PubMed

Porco, Travis C; Holbrook, Karen A; Fernyak, Susan E; Portnoy, Diane L; Reiter, Randy; Aragón, Tomás J

2004-08-06

Previous smallpox ring vaccination models based on contact tracing over a network suggest that ring vaccination would be effective, but have not explicitly included response logistics and limited numbers of vaccinators. We developed a continuous-time stochastic simulation of smallpox transmission, including network structure, post-exposure vaccination, vaccination of contacts of contacts, limited response capacity, heterogeneity in symptoms and infectiousness, vaccination prior to the discontinuation of routine vaccination, more rapid diagnosis due to public awareness, surveillance of asymptomatic contacts, and isolation of cases. We found that even in cases of very rapidly spreading smallpox, ring vaccination (when coupled with surveillance) is sufficient in most cases to eliminate smallpox quickly, assuming that 95% of household contacts are traced, 80% of workplace or social contacts are traced, and no casual contacts are traced, and that in most cases the ability to trace 1-5 individuals per day per index case is sufficient. If smallpox is assumed to be transmitted very quickly to contacts, it may at times escape containment by ring vaccination, but could be controlled in these circumstances by mass vaccination. Small introductions of smallpox are likely to be easily contained by ring vaccination, provided contact tracing is feasible. Uncertainties in the nature of bioterrorist smallpox (infectiousness, vaccine efficacy) support continued planning for ring vaccination as well as mass vaccination. If initiated, ring vaccination should be conducted without delays in vaccination, should include contacts of contacts (whenever there is sufficient capacity) and should be accompanied by increased public awareness and surveillance.

Influence of immediate loading on provisional restoration in dental implant stability

NASA Astrophysics Data System (ADS)

Ikbal, M.; Odang, R. W.; Indrasari, M.; Dewi, R. S.

2017-08-01

The success of dental implant treatment is determined by the primary stability at placement. One factor that could influence this stability is occlusal loading through provisional restoration. Two types of loading protocols are usually used: immediate and delayed loading. However, some controversies remain about the influence of occlusal loading on implant stability. Therefore, the influence of immediate loading on implant stability must be studied. An animal study was conducted by placing nine dental implants in the mandibular jaw of three Macaca fascicularis. Provisional restorations with various occlusal contacts (no, light, and normal contact) were placed on the implant. The implant stability was measured using the Ostell ISQ three times: immediately (baseline) and at the first and second months after implant placement. The implant stability between implants with no and normal occlusal contact as well as light and normal occlusal contact showed significant differences (p < 0.05) at the first and second months after implant placement. However, no significant increase (p > 0.05) in implant stability was seen at the baseline and the first and second months after implant placement for all occlusal contact groups. Immediate loading influenced the implant stability, and provisional restoration of implant without occlusal contact showed the highest implant stability.

Cost-effectiveness analysis of interferon beta-1b for the treatment of patients with a first clinical event suggestive of multiple sclerosis.

PubMed

Caloyeras, John P; Zhang, Bin; Wang, Cheng; Eriksson, Marianne; Fredrikson, Sten; Beckmann, Karola; Knappertz, Volker; Pohl, Christoph; Hartung, Hans-Peter; Shah, Dhvani; Miller, Jeffrey D; Sandbrink, Rupert; Lanius, Vivian; Gondek, Kathleen; Russell, Mason W

2012-05-01

To assess, from a Swedish societal perspective, the cost effectiveness of interferon β-1b (IFNB-1b) after an initial clinical event suggestive of multiple sclerosis (MS) (ie, early treatment) compared with treatment after onset of clinically definite MS (CDMS) (ie, delayed treatment). A Markov model was developed, using patient level data from the BENEFIT trial and published literature, to estimate health outcomes and costs associated with IFNB-1b for hypothetical cohorts of patients after an initial clinical event suggestive of MS. Health states were defined by Kurtzke Expanded Disability Status Scale (EDSS) scores. Model outcomes included quality-adjusted life years (QALYs), total costs (including both direct and indirect costs), and incremental cost-effectiveness ratios. Sensitivity analyses were performed on key model parameters to assess the robustness of model results. In the base case scenario, early IFNB-1b treatment was economically dominant (ie, less costly and more effective) versus delayed IFNB-1b treatment when QALYs were used as the effectiveness metric. Sensitivity analyses showed that the cost-effectiveness results were sensitive to model time horizon. Compared with the delayed treatment strategy, early treatment of MS was also associated with delayed EDSS progressions, prolonged time to CDMS diagnosis, and a reduction in frequency of relapse. Early treatment with IFNB-1b for a first clinical event suggestive of MS was found to improve patient outcomes while controlling costs. Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.

Assessment of the U937 cell line for the detection of contact allergens

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

Python, Francois; Goebel, Carsten; Aeby, Pierre

2007-04-15

The human myeloid cell line U937 was evaluated as an in vitro test system to identify contact sensitizers in order to develop alternatives to animal tests for the cosmetic industry. Specific culture conditions (i.e., presence of interleukin-4, IL-4) were applied to obtain a dendritic cell-like phenotype. In the described test protocol, these cells were exposed to test chemicals and then analyzed by flow cytometry for CD86 expression and by quantitative real-time reverse transcriptase-polymerase chain reaction for IL-1{beta} and IL-8 gene expressions. Eight sensitizers, three non-sensitizers and five oxidative hair dye precursors were examined after 24-, 48- and 72-h exposure times.more » Test item-specific modulations of the chosen activation markers (CD86, IL-1{beta} and IL-8) suggest that this U937 activation test could discriminate test items classified as contact sensitizers or non-sensitizers in the local lymph node assay in mice (LLNA). More specifically, a test item can be considered as a potential sensitizer when it significantly induced the upregulation of the expression of at least two markers. Using this approach, we could correctly evaluate the dendritic cell (DC) activation potential for 15 out of 16 tested chemicals. We conclude that the U937 activation test may represent an useful tool in a future in vitro test battery for predicting sensitizing properties of chemicals.« less

[Sensitization to Lyral].

PubMed

Heras, F; Díaz-Recuero, J L; Cabello, M J; Conde-Salazar, L

2006-01-01

Lyral is a fragrance that is present in many cosmetic products. It has turned into an emergent allergen during the last years. In studies carried out in other European countries, the prevalence of sensitization to Lyral has been found to be 1.9-2.7 %, but it is unknown the prevalence in Spain, as well as the need to include it or not in the standard series of the Spanish Group of Contact Dermatitis (GEIDC). We have patch-tested to Lyral all patients with suspicion of contact dermatitis of any origin who attended our Service between April and May-2005. From a total of 170 patients included in our study, 2 of them had a sensitization to Lyral (1.2 %). One of these two patients had an axillae contact dermatitis caused by a deodorant containing Lyral. The other patient was a masseur-woman with a contact dermatitis on both hands, with periods of dissemination to upper extremities and trunk, and who used several cosmetics products for private reasons and during her job. Although the sample of this study is quite small, we think that the results allow to suspect that Lyral is one of the main allergens, or even the most important, in causing allergic contact dermatitis to fragrances in our environment. Therefore, we believe that we must raise the inclusion of Lyral in the standard series of GEIDC, either as independent allergen, or including it in a new mixture of fragrances.

Contact allergy to preservatives: ESSCA* results with the baseline series, 2009-2012.

PubMed

Giménez-Arnau, A M; Deza, G; Bauer, A; Johnston, G A; Mahler, V; Schuttelaar, M-L; Sanchez-Perez, J; Silvestre, J F; Wilkinson, M; Uter, W

2017-04-01

Allergic contact dermatitis caused by biocides is common and causes significant patient morbidity. To describe the current frequency and pattern of patch test reactivity to biocide allergens included in the baseline series of most European countries. Data collected by the European Surveillance System on Contact Allergies (ESSCA) network between 2009 and 2012 from 12 European countries were analysed. Methylisothiazolinone 0.2% aq. produced the highest prevalence of sensitization during the study period, with an overall prevalence of 4.5%. The mixture methylchloroisothiazolinone /methylisothiazolinone tested at 0.02% aq. followed closely, with 4.1% of positive reactions. Other preservatives with lower rates of sensitization, but still over 1%, include methyldibromo glutaronitrile (MDBGN) 0.5% pet. and iodopropynyl butylcarbamate (IPBC) 0.2% pet. Formaldehyde releasers and parabens yielded less than 1% positive reactions during the study period. Some regional differences in the prevalence of contact allergy to biocides among European countries were observed. Contact allergy to biocides is common throughout Europe, and regional differences could be explained by differences in exposure or characteristics of the population tested. Timely regulatory action for isothiazolinones is required. Although MDBGN is banned from cosmetics products since 2005, sensitization prevalence has not appeared to plateau. IPBC is an emerging allergen with an increasing prevalence over the last few years, and its inclusion in the European baseline series may be appropriate. © 2016 European Academy of Dermatology and Venereology.

Airborne ultrasonic inspection in carbon/carbon composite materials

NASA Astrophysics Data System (ADS)

Yang, In-Young; Kim, Young-Hun; Park, Je-Woong; Hsu, David K.; Song, Song-Jin; Cho, Hyun-Jun; Kim, Sun-Kyu; Im, Kwang-Hee

2007-07-01

In this work, a carbon/carbon (C/C) composite material was nondestructively characterized with non-contact ultrasonic methods using automated acquisition scanner as well as contact ultrasonic measurement because (C/C) composite materials have obvious high price over conventional materials. Because of permeation of coupling medium such as water, it is desirable to perform contact-less nondestructive evaluation to assess material properties and part homogeneity. Also through transmission mode was performed because of the main limitation for air-coupled transducers, which is the acoustic impedance mismatch between most materials and air. Especially ultrasonic images and velocities for C/C composite disk brake was measured and found to be consistent to some degree with the non-contact and contact ultrasonic measurement methods. Low frequency through-transmission scans based on both amplitude and time-of-flight of the ultrasonic pulse were used for mapping out the material property inhomogeneity. Measured results were compared with those obtained by the motorized system with using dry-coupling ultrasonics and through transmission method in immersion. Finally, results using a proposed peak-delay measurement method well corresponded to ultrasonic velocities of the pulse overlap method.

Preservation of allergic contact dermatitis to poison ivy (urushiol) in late HIV disease. The implications and relevance to immunotherapy with contact allergens.

PubMed

Smith, K J; Skelton, H G; Nelson, A; Wagner, K F; Hackley, B E

1997-01-01

Delayed hypersensitivity reactions (DTH) are lost with progression of HIV disease. This loss of DTH commonly occurs before the onset of opportunistic infections and is an independent predictor of disease progression. We wanted to determine whether patients in late HIV disease with a history of allergic contact dermatitis (ACD) to poison ivy continue to react to poison ivy. Twelve HIV+ patients with a past history of ACD to poison ivy were tested with an extract prepared from poison ivy leaves. All but 1 patient had CD4+ T cell counts < 200/microliters, and 5 patients had had an opportunistic infection. All 12 patients showed positive reactions ranging from mild erythema and infiltration to marked erythema with bulla formation. ACD is considered a variant of DTH, and as DTH results in a T helper 1 cytokine pattern. However, the antigen-specific effector cells in ACD may be more diverse than in DTH. This diversity could explain the continued reaction to some contact allergens in late disease and may be important in the use of contact allergens for immunotherapy.

Age of onset of life-time mental disorders and treatment contact.

PubMed

Vaingankar, Janhavi Ajit; Rekhi, Gurpreet; Subramaniam, Mythily; Abdin, Edimansyah; Chong, Siow Ann

2013-05-01

Early onset of mental disorders is a major social and public health concern as it affects individuals in their most formative years. The impact is more pronounced when early onset is also associated with treatment delay. Little is known about the age of onset (AOO) for mental disorders and its predictors in Singapore. A national mental health survey was conducted among adult residents aged 18 years and above in Singapore. The composite international diagnostic interview (CIDI 3.0) was used to establish the life-time diagnosis of major depressive disorder (MDD), dysthymia, bipolar disorder, generalized anxiety disorder (GAD), obsessive compulsive disorder (OCD) and alcohol abuse and dependence, and the age of onset as well as any subsequent treatment contact. A total of 6,616 respondents (mean age of 43.9 years) participated in the survey giving a response rate of 75.9 %. The median AOO for having any one of the mental disorders was 22 years with variation among the different disorders. Predictors for AOO varied across the mental disorders. Only 8 % had sought any treatment in the first year after onset. Males, those belonging to Malay and Indian ethnicities and 50+ age cohorts were less likely to have made treatment contact in the year of onset. Nearly half of the respondents with any life-time mental disorder would have its onset by age of 22 years, and very few had sought treatment within the first year from onset. The study also identified socio-demographic predictors associated with AOO for mental disorders and delayed treatment contact, thus highlighting a vulnerable subpopulation that can be targeted for outreach and early interventions.

Biocompatibility of antimicrobial melimine lenses: rabbit and human studies.

PubMed

Dutta, Debarun; Ozkan, Jerome; Willcox, Mark D P

2014-05-01

Covalent immobilization of antimicrobial peptide melimine onto contact lenses can produce broad-spectrum antimicrobial lenses. The purpose of this study was to investigate the performance of melimine-coated contact lenses in an animal model and human clinical trial. Melimine was covalently attached onto the surface of contact lenses via EDC (1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride) coupling. A rabbit model of daily contralateral wear of lenses for 22 days was conducted to assess the lens safety. A prospective, randomized, double-masked, one-day human clinical trial was used to evaluate subjective responses and ocular physiology during contralateral wear of melimine-coated (test) and uncoated (control) lenses. Delayed reactions were monitored during follow-up visits after 1 and 4 weeks. Ex vivo retention of antimicrobial activity of worn lenses was assessed by reduction in numbers of viable Pseudomonas aeruginosa and Staphylococcus aureus. Melimine-coated lenses produced no ocular signs or symptoms that would indicate cytotoxicity during the lens wear of rabbits. No histological changes were found in rabbit corneas. During the human trial, no differences were observed in wettability, surface deposition, lens-fitting centration, movement, tightness, and corneal coverage between test and control lenses (p > 0.05). There were no significant differences in bulbar, limbal, or palpebral redness or conjunctival staining (p > 0.05). Mean corneal (extent, depth, and type) staining was higher for test lenses compared with that for control lenses (p < 0.05). There was no significant difference in subjective responses for lens comfort, dryness, and awareness (p > 0.05). No delayed reactions were associated with the test lenses. Worn test lenses retained more than 1.5 log inhibition against both bacterial types. Melimine-coated contact lenses were worn safely by humans. However, they were associated with higher corneal staining. The melimine-coated lenses retained high antibacterial activity after wear.

Composition, diffusion, and antifungal activity of black mustard (Brassica nigra) essential oil when applied by direct addition or vapor phase contact.

PubMed

Mejía-Garibay, Beatriz; Palou, Enrique; López-Malo, Aurelio

2015-04-01

In this study, we characterized the essential oil (EO) of black mustard (Brassica nigra) and quantified its antimicrobial activity, when applied by direct contact into the liquid medium or by exposure in the vapor phase (in laboratory media or in a bread-type product), against the growth of Aspergillus niger, Aspergillus ochraceus, or Penicillium citrinum. Allyl-isothiocyanate (AITC) was identified as the major component of B. nigra EO with a concentration of 378.35 mg/ml. When B. nigra EO was applied by direct contact into the liquid medium, it inhibited the growth of A. ochraceus and P. citrinum when the concentration was 2 μl/ml of liquid medium (MIC), while for A. niger, a MIC of B. nigra EO was 4 μl/ml of liquid medium. Exposure of molds to B. nigra EO in vapor phase showed that 41.1 μl of B. nigra EO per liter of air delayed the growth of P. citrinum and A. niger by 10 days, while A. ochraceus growth was delayed for 20 days. Exposure to concentrations ≥ 47 μl of B. nigra EO per liter of air (MIC) inhibited the growth of tested molds by 30 days, and they were not able to recover after further incubation into an environment free of EO (fungicidal effect). Adsorbed AITC was quantified by exposing potato dextrose agar to B. nigra EO in a vapor phase, exhibiting that AITC was retained at least 5 days when testing EO at its MIC or with higher concentrations. Mustard EO MIC was also effective against the evaluated molds inhibiting their growth for 30 days in a bread-type product when exposed to EO by vapor contact, demonstrating its antifungal activity.

Contact investigation outcomes of Canadian-born adults with tuberculosis in Indigenous and non-Indigenous populations in Alberta.

PubMed

Eisenbeis, Lisa; Gao, Zhiwei; Heffernan, Courtney; Yacoub, Wadieh; Long, Richard; Verma, Geetika

2016-06-27

Contact investigations are a critical component of tuberculosis control in high-income countries. However, the relative success of conventional methods by population group and place of residence is unknown. This study compares outcomes of contact investigations of Canadian-born Indigenous tuberculosis cases living on- and off-reserve with other Canadian-born cases. In a retrospective analysis, Canadian-born adult culture-positive pulmonary TB cases (2001-2010) were identified. Characteristics of source cases and their contacts were compared by population group. Outcomes of contact investigations, including completion of recommended investigations and preventive therapy, were compared in multivariable analysis. Of 171 cases of tuberculosis identified, 49 (29%) were Indigenous on-reserve, 62 (36%) Indigenous off-reserve, and 60 (35%) non-Indigenous or Canadian-born, "other". Indigenous people had more contacts identified per case compared to non-Indigenous patients. Case population group and smear status were the main predictors of the success of contact investigations. Of those recommended preventive therapy, close contacts of Indigenous cases on-reserve had the highest rate of completion, at 54%, vs. 41% and 37% for close contacts of Indigenous living off-reserve and Canadian-born "other" respectively (p = 0.02). Contacts of Indigenous cases living off-reserve had the greatest delay in assessment and the lowest rates of completion of assessment and preventive therapy. In multivariable analysis, population group, smear status of source case and proximity of contact were predictors of preventive therapy acceptance and/or completion. Significant differences in outcomes of contact investigations were observed between population groups. The higher priority of contacts of smear-positive cases appears to influence efficiency of service delivery, regardless of population group. Jurisdictional differences in program delivery, resource availability and perceived risk of transmission likely influence outcomes of contact investigations.

Effects of stochastic time-delayed feedback on a dynamical system modeling a chemical oscillator.

PubMed

González Ochoa, Héctor O; Perales, Gualberto Solís; Epstein, Irving R; Femat, Ricardo

2018-05-01

We examine how stochastic time-delayed negative feedback affects the dynamical behavior of a model oscillatory reaction. We apply constant and stochastic time-delayed negative feedbacks to a point Field-Körös-Noyes photosensitive oscillator and compare their effects. Negative feedback is applied in the form of simulated inhibitory electromagnetic radiation with an intensity proportional to the concentration of oxidized light-sensitive catalyst in the oscillator. We first characterize the system under nondelayed inhibitory feedback; then we explore and compare the effects of constant (deterministic) versus stochastic time-delayed feedback. We find that the oscillatory amplitude, frequency, and waveform are essentially preserved when low-dispersion stochastic delayed feedback is used, whereas small but measurable changes appear when a large dispersion is applied.

Do Right- and Left-Handed Monkeys Differ on Cognitive Measures?

NASA Technical Reports Server (NTRS)

Hopkins, William D.; Washburn, David A.

1994-01-01

Twelve left- and 14 right-handed monkeys were compared on 6 measures of cognitive performance (2 maze-solving tasks, matching-to-sample, delayed matching-to-sample, delayed response using spatial cues, and delayed response using form cues). The dependent variable was trials-to-training criterion for each of the 6 tasks. Significant differences were found between left- and right-handed monkeys on the 2 versions of the delayed response task. Right-handed monkeys reached criterion significantly faster on the form cue version of the task, whereas left-handed monkeys reached criterion significantly faster on delayed response for spatial position (p less than .05). The results suggest that sensitive hand preference measures of laterality can reveal differences in cognitive performance, which in turn may reflect underlying laterality in functional organization of the nervous system.

Effects of stochastic time-delayed feedback on a dynamical system modeling a chemical oscillator

NASA Astrophysics Data System (ADS)

González Ochoa, Héctor O.; Perales, Gualberto Solís; Epstein, Irving R.; Femat, Ricardo

2018-05-01

We examine how stochastic time-delayed negative feedback affects the dynamical behavior of a model oscillatory reaction. We apply constant and stochastic time-delayed negative feedbacks to a point Field-Körös-Noyes photosensitive oscillator and compare their effects. Negative feedback is applied in the form of simulated inhibitory electromagnetic radiation with an intensity proportional to the concentration of oxidized light-sensitive catalyst in the oscillator. We first characterize the system under nondelayed inhibitory feedback; then we explore and compare the effects of constant (deterministic) versus stochastic time-delayed feedback. We find that the oscillatory amplitude, frequency, and waveform are essentially preserved when low-dispersion stochastic delayed feedback is used, whereas small but measurable changes appear when a large dispersion is applied.

Insensitivity of synchronization to network structure in chaotic pendulum systems with time-delay coupling.

PubMed

Yao, Chenggui; Zhan, Meng; Shuai, Jianwei; Ma, Jun; Kurths, Jürgen

2017-12-01

It has been generally believed that both time delay and network structure could play a crucial role in determining collective dynamical behaviors in complex systems. In this work, we study the influence of coupling strength, time delay, and network topology on synchronization behavior in delay-coupled networks of chaotic pendulums. Interestingly, we find that the threshold value of the coupling strength for complete synchronization in such networks strongly depends on the time delay in the coupling, but appears to be insensitive to the network structure. This lack of sensitivity was numerically tested in several typical regular networks, such as different locally and globally coupled ones as well as in several complex networks, such as small-world and scale-free networks. Furthermore, we find that the emergence of a synchronous periodic state induced by time delay is of key importance for the complete synchronization.

Tuberculosis and nutrition: disease perceptions and health seeking behavior of household contacts in the Peruvian Amazon

PubMed Central

Baldwin, M. R.; Yori, P. P.; Ford, C.; Moore, D. A. J.; Gilman, R. H.; Vidal, C.; Ticona, E.; Evans, C. A.

2010-01-01

SETTING Households of TB patients in the Peruvian Amazon. OBJECTIVE To investigate how knowledge and beliefs of household contacts about TB affected health seeking behavior. DESIGN Interviews with 73 patients finishing treatment and 79 of their adult household contacts. RESULTS Contacts were knowledgeable about free screening and treatment, but contacts who noted weight loss, not cough, were more likely to be screened for TB (P = 0.03). Forty-two per cent reported that TB was prevented by nutrition, 28% by separating eating utensils, and only 19% by avoiding a coughing patient. Only one household contact reported being stigmatized. Stigma centered upon nutrition, and only 12% knew of the association between TB and HIV. Only 14% had a BMI <20, yet 30% reported regularly going to sleep hungry. Free food packages were reported to be the most important reason for treatment adherence by 33% of patients. CONCLUSION Contacts misperceived TB as a nutritional disease and did not fear airborne transmission, which should be corrected by public health education. Weight loss, and not cough, led to screening. Stigma appeared to be minimized because risk was perceived as personal, through malnutrition, rather than exposure-based. Nutritional incentives that utilize these beliefs may reduce diagnostic delay and enhance treatment adherence. PMID:15636496

Cell Electrosensitization Exists Only in Certain Electroporation Buffers.

PubMed

Dermol, Janja; Pakhomova, Olga N; Pakhomov, Andrei G; Miklavčič, Damijan

2016-01-01

Electroporation-induced cell sensitization was described as the occurrence of a delayed hypersensitivity to electric pulses caused by pretreating cells with electric pulses. It was achieved by increasing the duration of the electroporation treatment at the same cumulative energy input. It could be exploited in electroporation-based treatments such as electrochemotherapy and tissue ablation with irreversible electroporation. The mechanisms responsible for cell sensitization, however, have not yet been identified. We investigated cell sensitization dynamics in five different electroporation buffers. We split a pulse train into two trains varying the delay between them and measured the propidium uptake by fluorescence microscopy. By fitting the first-order model to the experimental results, we determined the uptake due to each train (i.e. the first and the second) and the corresponding resealing constant. Cell sensitization was observed in the growth medium but not in other tested buffers. The effect of pulse repetition frequency, cell size change, cytoskeleton disruption and calcium influx do not adequately explain cell sensitization. Based on our results, we can conclude that cell sensitization is a sum of several processes and is buffer dependent. Further research is needed to determine its generality and to identify underlying mechanisms.

Cell Electrosensitization Exists Only in Certain Electroporation Buffers

PubMed Central

Dermol, Janja; Pakhomova, Olga N.; Pakhomov, Andrei G.; Miklavčič, Damijan

2016-01-01

Electroporation-induced cell sensitization was described as the occurrence of a delayed hypersensitivity to electric pulses caused by pretreating cells with electric pulses. It was achieved by increasing the duration of the electroporation treatment at the same cumulative energy input. It could be exploited in electroporation-based treatments such as electrochemotherapy and tissue ablation with irreversible electroporation. The mechanisms responsible for cell sensitization, however, have not yet been identified. We investigated cell sensitization dynamics in five different electroporation buffers. We split a pulse train into two trains varying the delay between them and measured the propidium uptake by fluorescence microscopy. By fitting the first-order model to the experimental results, we determined the uptake due to each train (i.e. the first and the second) and the corresponding resealing constant. Cell sensitization was observed in the growth medium but not in other tested buffers. The effect of pulse repetition frequency, cell size change, cytoskeleton disruption and calcium influx do not adequately explain cell sensitization. Based on our results, we can conclude that cell sensitization is a sum of several processes and is buffer dependent. Further research is needed to determine its generality and to identify underlying mechanisms. PMID:27454174

Sensitivity of Dynamical Systems to Banach Space Parameters

DTIC Science & Technology

2005-02-13

We consider general nonlinear dynamical systems in a Banach space with dependence on parameters in a second Banach space. An abstract theoretical ... framework for sensitivity equations is developed. An application to measure dependent delay differential systems arising in a class of HIV models is presented.

Decreased sensitivity of early imaging with In-111 oxine-labeled leukocytes in detection of occult infection: concise communication

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

Datz, F.L.; Jacobs, J.; Baker, W.

1984-03-01

Imaging with leukocytes labeled with indium-111 oxine is a sensitive technique for detecting sites of occult infection. Traditionally, imaging is performed 24 hr after injection. The authors undertook a prospective study of 35 patients (40 studies) with possible occult infection to see whether a 24-hr delay in imaging is really necessary. Patients were imaged at 1-4 hr and again at 24 hr after injection. The early images had a sensitivity of only 33%, compared with 95% for the 24-hr images. Of the seven studies that were positive on both early and delayed images, 71% had more intense uptake at 24more » hr. There were no false-positive early images. It was concluded that imaging 1-4 hr after injection with In-111 oxine-labeled leukocytes has a low sensitivity for detecting occult infection. However, a positive early image is specific for a site of infection.« less

[Comparative analysis of visual function and the quality of life index with eyeglasses or a progressive contact lens].

PubMed

Sant'Anna, Neusa Vidal; Schor, Paulo; Lipener, César; Uras, Ricardo

2006-01-01

To compare the visual function and the answers to a questionnaire of quality of life of patients wearing a progressive contact lens or eyeglasses. The Focus Progressive contact lens had been fitted in 35 patients with far visual acuity with progressive-addition eyeglasses equal to zero (log MAR) and near J1 (Jaeger). The far and near visual acuities and the measurement of contrast sensitivity were compared when the patients were wearing the eyeglasses or the contact lens and the patients' results of the scores of the quality of life questionnaire (NEI VFQ-25) were analyzed statistically considering the type of ametropy and the age. The far and near visual acuities and the contrast sensitivity measurement were worse with the contact lens than with eyeglasses. The answers to the questionnaire did not differ when were comparing the same patients wearing eyeglasses or contact lens, no matter the type of ametropy. The myopic and the hyperopic subgroups had worse answers to the quality of life questionnaire when corrected with the contact lens than with eyeglasses, both with age equal to or less than their median. The visual function was worse with the contact lens. The type of ametropy did not influence the answers to the quality of life questionnaire considering the optical correction, but age did.

Caudate responses to reward anticipation associated with delay discounting behavior in healthy youth

PubMed Central

Benningfield, Margaret M.; Blackford, Jennifer U.; Ellsworth, Melissa E.; Samanez-Larkin, Gregory R.; Martin, Peter R.; Cowan, Ronald L.; Zald, David H.

2014-01-01

Background Choices requiring delay of gratification made during adolescence can have significant impact on life trajectory. Willingness to delay gratification can be measured using delay discounting tasks that require a choice between a smaller immediate reward and a larger delayed reward. Individual differences in the subjective value of delayed rewards are associated with risk for development of psychopathology including substance abuse. The neurobiological underpinnings related to these individual differences early in life are not fully understood. Using functional magnetic resonance imaging (fMRI), we tested the hypothesis that individual differences in delay discounting behavior in healthy youth are related to differences in responsiveness to potential reward. Method Nineteen 10 to 14 year-olds performed a monetary incentive delay task to assess neural sensitivity to potential reward and a questionnaire to measure discounting of future monetary rewards. Results Left ventromedial caudate activation during anticipation of potential reward was negatively correlated with delay discounting behavior. There were no regions where brain responses during notification of reward outcome were associated with discounting behavior. Conclusions Brain activation during anticipation of potential reward may serve as a marker for individual differences in ability or willingness to delay gratification in healthy youth. PMID:24309299

Two Cases of Occupational Contact Urticaria Caused by Percutaneous Sensitization to Parvalbumin

PubMed Central

Sano, Akiyo; Yagami, Akiko; Suzuki, Kayoko; Iwata, Yohei; Kobayashi, Tsukane; Arima, Masaru; Kondo, Yasuto; Yoshikawa, Tetsushi; Matsunaga, Kayoko

2015-01-01

Background In recent years, it has been proposed that the primary mechanism for the development of food allergies is percutaneous sensitization. Since 2010, in Japan, the number of immediate-type wheat allergy due to hydrolyzed wheat protein has dramatically increased among those who have been using soap containing hydrolyzed wheat. This incidence supports the hypothesis that food allergens arise through percutaneous sensitization. Clinical Summary A 25-year-old man (case 1) and an 18-year-old girl (case 2) with atopic dermatitis visited our Department because of food allergy and hand eczema. After starting their work with fish, severe itchy eczema appeared on their hands. They subsequently started to experience oral allergic symptoms, intraoral itchiness and dyspnea after eating fish. Specific IgE antibodies were detected for many fishes, and skin prick tests showed positive reactions for a variety of fishes in both cases. Furthermore, the fluorescence intensities of specific IgE antibodies against parvalbumin from various types of fish in microarray immunoassay analysis showed positive reactions. We diagnosed them as contact urticaria caused by percutaneous sensitization to parvalbumin through job-related physical contact with fish. Conclusion The patients' histories and findings indicate the possibility of percutaneous sensitization through occupational exposure to parvalbumin, leading to food allergy. PMID:26464568

The Usefulness of M-B CDI-K Short Form as Screening Test in Children With Language Developmental Delay.

PubMed

Kim, Seong Woo; Jeon, Ha Ra; Park, Eun Ji; Kim, Hyo In; Jung, Da Wa; Woo, Mee Ryung

2014-06-01

To investigate the usefulness of MacArthur-Bates Communicative Development Inventories-Korean (M-B CDI-K) short form as a screening test in children with language developmental delay. From April 2010 to May 2012, a total of 87 patients visited the department of physical medicine and rehabilitation of National Health Insurance Service Ilsan Hospital with the complaint of language developmental delay and were enrolled in this study. All patients took M-B CDI-K short form and Sequenced Language Scale for Infants (SELSI) or Preschool Receptive-Expressive Language Scale (PRES) according to their age. The study group consisted of 58 male patients and 29 female patients and the mean age was 25.9 months. The diagnosis are global developmental delay in 26 patients, selective language impairment in 31 patients, articulation disorder in 7 patients, cerebral palsy in 8 patients, autism spectrum disorder in 4 patients, motor developmental delay in 4 patients, and others in 7 patients. Seventy-one patients are diagnosed with language developmental delay in SELSI or PRES and of them showed 69 patients a high risk in the M-B CDI-K short form. Sixteen patients are normal in SELSI or PRES and of them showed 14 patients non-high risk in the M-B CDI-K short form. The M-B CDI-K short form has 97.2% sensitivity, 87.5% specificity, a positive predictive value of 0.97, and a negative predictive value of 0.88. The M-B CDI-K short form has a high sensitivity and specificity so it is considered as an useful screening tool in children with language developmental delay. Additional researches targeting normal children will be continued to supply the specificity of the M-B CDI-K short form.

Sensitivity analysis in a Lassa fever deterministic mathematical model

NASA Astrophysics Data System (ADS)

Abdullahi, Mohammed Baba; Doko, Umar Chado; Mamuda, Mamman

2015-05-01

Lassa virus that causes the Lassa fever is on the list of potential bio-weapons agents. It was recently imported into Germany, the Netherlands, the United Kingdom and the United States as a consequence of the rapid growth of international traffic. A model with five mutually exclusive compartments related to Lassa fever is presented and the basic reproduction number analyzed. A sensitivity analysis of the deterministic model is performed. This is done in order to determine the relative importance of the model parameters to the disease transmission. The result of the sensitivity analysis shows that the most sensitive parameter is the human immigration, followed by human recovery rate, then person to person contact. This suggests that control strategies should target human immigration, effective drugs for treatment and education to reduced person to person contact.

Assessing the toxicity of sediments using the medaka embryo-larval assay and 2 other bioassays.

PubMed

Barhoumi, Badreddine; Clérandeau, Christelle; Landi, Laure; Pichon, Anaïk; Le Bihanic, Florane; Poirier, Dominique; Anschutz, Pierre; Budzinski, Hélène; Driss, Mohamed Ridha; Cachot, Jérôme

2016-09-01

Sediments are sinks for aquatic pollutants, and analyzing toxicity in such complex matrices is still challenging. To evaluate the toxicity of bioavailable pollutants accumulated in sediments from the Bizerte lagoon (Tunisia), a novel assay, the medaka embryo-larval assay by sediment contact, was applied. Japanese medaka (Oryzias latipes) embryos were incubated in direct contact with sediment samples up to hatching. Lethal and sublethal adverse effects were recorded in embryos and larvae up to 20 d postfertilization. Results from medaka embryo-larval assay were compared with cytotoxicity (Microtox®), genotoxicity (SOS chromotest), and pollutant content of sediments. The results highlight differences in the contamination profile and toxicity pattern between the different studied sediments. A significant correlation was shown between medaka embryo-larval assay by sediment contact and SOS chromotest responses and concentrations of most organic pollutants studied. No correlation was shown between pollutant levels and Microtox. According to the number of sediment samples detected as toxic, medaka embryo-larval assay by sediment contact was more sensitive than Microtox, which in turn was more sensitive than the SOS chromotest; and medaka embryo-larval assay by sediment contact allowed sediment toxicity assessment of moderately polluted sediments without pollutant extraction and using an ecologically realistic exposure scenario. Although medaka embryo-larval assay by sediment contact should be tested on a larger sample set, the results show that it is sensitive and convenient enough to monitor the toxicity of natural sediments. Environ Toxicol Chem 2016;35:2270-2280. © 2016 SETAC. © 2016 SETAC.

Involvement of the cannabinoid CB2 receptor and its endogenous ligand 2-arachidonoylglycerol in oxazolone-induced contact dermatitis in mice.

PubMed

Oka, Saori; Wakui, Junichi; Ikeda, Shinobu; Yanagimoto, Shin; Kishimoto, Seishi; Gokoh, Maiko; Nasui, Miwako; Sugiura, Takayuki

2006-12-15

The possible involvement of 2-arachidonoylglycerol (2-AG), an endogenous ligand for the cannabinoid receptors (CB1 and CB2), in contact dermatitis in mouse ear was investigated. We found that the level of 2-AG was markedly elevated in the ear following a challenge with oxazolone in sensitized mice. Of note, the swelling following the challenge was suppressed by either the administration of SR144528, a CB2 receptor antagonist, immediately after sensitization, or the administration of SR144528 upon the challenge. The effect of AM251, a CB1 receptor antagonist, was marginal in either case. It seems apparent, therefore, that the CB2 receptor and its endogenous ligand 2-AG are closely involved in both the sensitization phase and the elicitation phase of oxazolone-induced contact dermatitis. In line with this, we found that Langerhans cells (MHC class II(+)) contain a substantial amount of CB2 receptor mRNA, whereas keratinocytes (MHC class II(-)) do not. We also obtained evidence that the expression of mRNAs for proinflammatory cytokines following a challenge with oxazolone was markedly suppressed by treatment with SR144528. We next examined whether the CB2 receptor and 2-AG participate in chronic contact dermatitis accompanied by the infiltration of tissues by eosinophils. The amount of 2-AG in mouse ear dramatically increased following repeated challenge with oxazolone. Importantly, treatment with SR144528 attenuated both the recruitment of eosinophils and ear swelling in chronic contact dermatitis induced by repeated challenge with oxazolone. These results strongly suggest that the CB2 receptor and 2-AG play important stimulative roles in the sensitization, elicitation, and exacerbation of allergic inflammation.

Neural tuning matches frequency-dependent time differences between the ears

PubMed Central

Benichoux, Victor; Fontaine, Bertrand; Franken, Tom P; Karino, Shotaro; Joris, Philip X; Brette, Romain

2015-01-01

The time it takes a sound to travel from source to ear differs between the ears and creates an interaural delay. It varies systematically with spatial direction and is generally modeled as a pure time delay, independent of frequency. In acoustical recordings, we found that interaural delay varies with frequency at a fine scale. In physiological recordings of midbrain neurons sensitive to interaural delay, we found that preferred delay also varies with sound frequency. Similar observations reported earlier were not incorporated in a functional framework. We find that the frequency dependence of acoustical and physiological interaural delays are matched in key respects. This suggests that binaural neurons are tuned to acoustical features of ecological environments, rather than to fixed interaural delays. Using recordings from the nerve and brainstem we show that this tuning may emerge from neurons detecting coincidences between input fibers that are mistuned in frequency. DOI: http://dx.doi.org/10.7554/eLife.06072.001 PMID:25915620

Ladder-structured photonic variable delay device

NASA Technical Reports Server (NTRS)

Yao, X. Steve (Inventor)

1998-01-01

An ladder-structured variable delay device for providing variable true time delay to multiple optical beams simultaneously. The device comprises multiple basic units stacked on top of each other resembling a ladder. Each basic unit comprises a polarization sensitive corner reflector formed by two polarization beamsplitters and a polarization rotator array placed parallel to the hypotenuse of the corner reflector. Controlling an array element of the polarization rotator array causes an optical beam passing through the array element to either go up to a basic unit above it or reflect back towards output. The beams going higher on the ladder experience longer optical path delay. Finally, the ladder-structured variable device can be cascaded with another multi-channel delay device to form a new device which combines the advantages of the two individual devices. This programmable optic device has the properties of high packing density, low loss, easy fabrication, and virtually infinite bandwidth. In addition, the delay is reversible so that the same delay device can be used for both antenna transmitting and receiving.

Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam.

PubMed

Kieć-Świerczyńska, Marta; Swierczyńska-Machura, Dominika; Chomiczewska-Skóra, Dorota; Nowakowska-Świrta, Ewa; Kręcisz, Beata

2014-04-01

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4'-diphenylmethane diisocyanate (MDI). From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent. Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers. In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.

Effects of amphetamine on delay discounting in rats depend upon the manner in which delay is varied

PubMed Central

Maguire, David R; Henson, Cedric; France, Charles P

2014-01-01

Whether stimulant drugs like amphetamine increase or decrease choice of larger delayed reinforcers over smaller immediately available reinforcers under delay discounting procedures can depend on several factors, including the order in which delay is presented. This study examined whether the order of delay presentation impacts drug effects on discounting in rats (n=8) trained and tested under an ascending order, a descending order, as well as under a fixed delay condition. Responses on one lever delivered 1 food pellet immediately and responses on the other lever delivered 3 food pellets immediately or after a delay (4–32 s). In Experiment 1, the delay to the larger reinforcer varied within session and the order of delay presentation (ascending or descending) varied across conditions. In Experiment 2, the same delay value was presented in all blocks of the session (i.e., delay was fixed), and delay varied across phases. Under the ascending order of delay, amphetamine (0.32–1.78 mg/kg) increased choice of the larger reinforcer in some rats and decreased choice in others. In the same rats responding under the descending and fixed delay conditions, amphetamine markedly decreased choice of the larger reinforcer even in the component associated with no delay. In some subjects, the effects of amphetamine differed depending on the manner in which delay was presented, indicating that drug-induced changes in performance were due, in part, to mechanisms other than altered sensitivity to reinforcer delay. These results also suggest that a history of responding under both orders of delay presentation can modulate drug effects. PMID:24780379

Stability and chaotification of vibration isolation floating raft systems with time-delayed feedback control.

PubMed

Li, Y L; Xu, D L; Fu, Y M; Zhou, J X

2011-09-01

This paper presents a systematic study on the stability of a two-dimensional vibration isolation floating raft system with a time-delayed feedback control. Based on the generalized Sturm criterion, the critical control gain for the delay-independent stability region and critical time delays for the stability switches are derived. The critical conditions can provide a theoretical guidance of chaotification design for line spectra reduction. Numerical simulations verify the correctness of the approach. Bifurcation analyses reveal that chaotification is more likely to occur in unstable region defined by these critical conditions, and the stiffness of the floating raft and mass ratio are the sensitive parameters to reduce critical control gain.

Language and social/emotional problems identified at a universal developmental assessment at 30 months

PubMed Central

2013-01-01

Background Preschool language and neurodevelopmental problems often persist and impede learning. The aims of the current study are to assess the uptake of a new universal 30 month health visitor contact and to quantify the prevalence of language delay and social/emotional difficulties. Methods All families of 30 month old children in four Glasgow localities were offered a visit from their health visitor. Structured data were collected relating to language, social and emotional development using three instruments; The Strengths and Difficulties Questionnaire (SDQ), the abbreviated Sure Start Language Measure and a two-item language screen. Results From an eligible population of 543 children, there was a 90% return rate of contact forms from the health visitors, and assessments were completed on 78% of eligible children. Visit completion rates did not differ significantly by socio-economic status. 3-8% of children were reported to have language delay depending on the method of assessment. 8.8% of children scored in the “abnormal” range of SDQ total difficulties scores and 31.1% had an abnormality in at least one subscale. There was substantial overlap between language delay and abnormal scores on the SDQ. Conclusions Universal assessment of neurodevelopmental function at 30 months identified a significant proportion of children, including those previously considered at low risk, with both language and social/emotional difficulties. Further work is required to assess the precise nature of these difficulties and to assess the potential impact on services. PMID:24330767

Rapid Acquisition of Preference in Concurrent Chains: Effects of "d"-Amphetamine on Sensitivity to Reinforcement Delay

ERIC Educational Resources Information Center

Ta, Wei-Min; Pitts, Raymond C.; Hughes, Christine E.; McLean, Anthony P.; Grace, Randolph C.

2008-01-01

The purpose of this study was to examine effects of "d"-amphetamine on choice controlled by reinforcement delay. Eight pigeons responded under a concurrent-chains procedure in which one terminal-link schedule was always fixed- interval 8 s, and the other terminal-link schedule changed from session to session between fixed-interval 4 s and…

Formation of retinal direction-selective circuitry initiated by starburst amacrine cell homotypic contact

PubMed Central

Ray, Thomas A; Roy, Suva; Kozlowski, Christopher; Wang, Jingjing; Cafaro, Jon; Hulbert, Samuel W; Wright, Christopher V; Field, Greg D

2018-01-01

A common strategy by which developing neurons locate their synaptic partners is through projections to circuit-specific neuropil sublayers. Once established, sublayers serve as a substrate for selective synapse formation, but how sublayers arise during neurodevelopment remains unknown. Here, we identify the earliest events that initiate formation of the direction-selective circuit in the inner plexiform layer of mouse retina. We demonstrate that radially migrating newborn starburst amacrine cells establish homotypic contacts on arrival at the inner retina. These contacts, mediated by the cell-surface protein MEGF10, trigger neuropil innervation resulting in generation of two sublayers comprising starburst-cell dendrites. This dendritic scaffold then recruits projections from circuit partners. Abolishing MEGF10-mediated contacts profoundly delays and ultimately disrupts sublayer formation, leading to broader direction tuning and weaker direction-selectivity in retinal ganglion cells. Our findings reveal a mechanism by which differentiating neurons transition from migratory to mature morphology, and highlight this mechanism’s importance in forming circuit-specific sublayers. PMID:29611808

[Contact allergic gastritis : Rare manifestation of a metal allergy].

PubMed

Pföhler, C; Vogt, T; Müller, C S L

2016-05-01

Only a few cases of contact allergic gastritis in patients with nickel allergy have been reported in the literature. We report a case of probable contact-allergic gastritis in a 46-year-old woman. Clinical examination revealed lichenoid mucosal lesions of the gums adjacent to a bridge and crowns that had been implanted several weeks previously. Since implantation, the patient suffered from gastrointestinal complaints including stomach pain. Gastroscopy and histological investigation of stomach biopsies showed eosinophilic gastritis. Patch testing done under the diagnosis of contact allergic stomatitis showed positive reactions to gold sodium thiosulphate, manganese (II) chloride, nickel (II) sulphate, palladium chloride, vanadium (III) chloride, zirconium (IV) chloride, and fragrances. The crowns and the bridge contained gold, palladium, and zirconium, hence they were replaced by titan-based dentition. Shortly after replacing the artificial dentition, all gastrointestinal symptoms resolved spontaneously without further treatment. Delayed-type allergy to components in the artificial dentition seem to have caused the gastritis.

Influence of reactive fillers on concrete corrosion resistance

NASA Astrophysics Data System (ADS)

Rakhimbayev, Sh M.; Tolypina, N. M.; Khakhaleva, E. N.

2018-03-01

Contact surfaces represent the weakest link in a conglomerate structure of materials. They ensure the diffusion of aggressive agents inside the material. To reduce the conductivity of contact surfaces it is advisable to use reactive fillers, which interact with cement matrix via certain mechanisms, which in turn, reduces the permeability of the contact layer and fosters durability of products. The interaction of reactive fillers with calcium hydroxide of a concrete liquid phase in a contact area leads to the formation of hydrated calcium silicates of a tobermorite group. Such compounds, being settled in pores and capillaries of a product, colmatage and clog them to some extent thus leading to diffusion delay (inhibition) with regard to aggressive components of external media inside porous material, which in turn inhibits the corrosion rate. The authors studied and compared the corrosion of cement concrete with a standard filler (quartz sand) and a reactive filler (perlite and urtit). The experiments confirmed the positive influence of active fillers on concrete corrosion resistance.

Defect-free erbium silicide formation using an ultrathin Ni interlayer.

PubMed

Choi, Juyun; Choi, Seongheum; Kang, Yu-Seon; Na, Sekwon; Lee, Hoo-Jeong; Cho, Mann-Ho; Kim, Hyoungsub

2014-08-27

An ultrathin Ni interlayer (∼1 nm) was introduced between a TaN-capped Er film and a Si substrate to prevent the formation of surface defects during thermal Er silicidation. A nickel silicide interfacial layer formed at low temperatures and incurred uniform nucleation and the growth of a subsequently formed erbium silicide film, effectively inhibiting the generation of recessed-type surface defects and improving the surface roughness. As a side effect, the complete transformation of Er to erbium silicide was somewhat delayed, and the electrical contact property at low annealing temperatures was dominated by the nickel silicide phase with a high Schottky barrier height. After high-temperature annealing, the early-formed interfacial layer interacted with the growing erbium silicide, presumably forming an erbium silicide-rich Er-Si-Ni mixture. As a result, the electrical contact property reverted to that of the low-resistive erbium silicide/Si contact case, which warrants a promising source/drain contact application for future high-performance metal-oxide-semiconductor field-effect transistors.

A position- and time-sensitive photon-counting detector with delay- line read-out

NASA Astrophysics Data System (ADS)

Jagutzki, Ottmar; Dangendorf, Volker; Lauck, Ronald; Czasch, Achim; Milnes, James

2007-05-01

We have developed image intensifier tubes with delay-anode read-out for time- and position-sensitive photon counting. The timing precision is better than 1 ns with 1000x1000 pixels position resolution and up to one megacounts/s processing rate. Large format detectors of 40 and 75 mm active diameter with internal helical-wire delay-line anodes have been produced and specified. A different type of 40 and 25 mm tubes with semi-conducting screen for image charge read-out allow for an economic and robust tube design and for placing the read-out anodes outside the sealed housing. Two types of external delay-line anodes, i.e. pick-up electrodes for the image charge, have been tested. We present tests of the detector and anode performance. Due to the low background this technique is well suited for applications with very low light intensity and especially if a precise time tagging for each photon is required. As an example we present the application of scintillator read-out in time-of-flight (TOF) neutron radiography. Further applications so far are Fluorescence Life-time Microscopy (FLIM) and Astronomy.

The Pathogenesis of Subacute Subdural Hematoma: A Report of 3 Cases and Literature Review.

PubMed

Tao, Zhi-Qiang; Ding, Sheng-Hong; Huang, Jian-Yue; Zhu, Zhi-Gang

2018-06-01

To discuss the pathologic mechanism of subacute subdural hematoma (sASDH). Three typical cases of sASDH were reported, and related literature in Chinese published in the past 15 years was reviewed. Intervals from onset of acute subdural hematoma to surgery or symptom deterioration resulting in sASDH were 12.5-15.5 days (mean 14.1 days). Delayed liquefaction of hematoma clots occurred in all 3 reported cases. One patient achieved good curative effect after administration of dexamethasone, and another patient relapsed owing to poor drainage after evacuation of hematoma. The conversion of acute subdural hematoma to sASDH is an inflammatory reaction process with very regular in time, and it is speculated that the pathologic mechanism may be a delayed hypersensitivity reaction. Antigen released during the liquefaction process of blood clot, with subdural neomembrane cells as antigen-presenting cells, is presented to the T lymphocytes released from the capillaries in the neomembrane and forms sensitized T lymphocytes. When the subsequent antigen is released from the blood clots with a delayed liquefaction and is exposed to sensitized T lymphocytes, the delayed hypersensitivity process occurs. Copyright © 2018 Elsevier Inc. All rights reserved.

Sensitized phosphorescence of benzil-doped ladder-type methyl-poly(para-phenylene).

PubMed

Bagnich, S A; Bässler, H; Neher, D

2004-11-08

The delayed luminescence and phosphorescence of ladder-type methyl-poly(para-phenylene) (MeLPPP) doped with benzil at a concentration of 20% by weight has been measured. The introduction of benzil leads to a dramatic reduction of the polymer singlet emission. At the same time, a new band with maximum at 611 nm appears, corresponding to the phosphorescence of MeLPPP. The phosphorescence decay on the short time scale is close to an exponential law with a time decay of 15 ms. This indicates that benzil can efficiently sensitize the phosphorescence of the polymer. In addition, a broad and featureless emission is observed in the delayed luminescence spectra of benzil-doped MeLPPP, which is attributed to an exciplex formed between the polymer host and the dopant. We further observe that the delayed fluorescence is enhanced by the addition of benzil. It is concluded that the delayed fluorescence of benzil-doped MeLPPP is mainly due to the annihilation of triplet excitons on the polymer. Finally, efficient triplet-triplet energy transfer from the benzil-doped polymer to the red-emitting phosphorescent dye Pt(II)octaethylporphyrin is established. Copyright 2004 American Institute of Physics.

Maternal Sensitivity and Communication Styles: Mothers with Depression

ERIC Educational Resources Information Center

Hwa-Froelich, Deborah A.; Loveland Cook, Cynthia A.; Flick, Louise H.

2008-01-01

Women living in poverty are at increased risk for depression, especially during their childbearing years. Whereas poverty has known adverse effects on children's cognitive, social, and communication development, maternal depression may place these children at additional risk of developmental delays. The maternal sensitivity of mothers with and…

A contact-area model for rail-pads connections in 2-D simulations: sensitivity analysis of train-induced vibrations

NASA Astrophysics Data System (ADS)

Ferrara, R.; Leonardi, G.; Jourdan, F.

2013-09-01

A numerical model to predict train-induced vibrations is presented. The dynamic computation considers mutual interactions in vehicle/track coupled systems by means of a finite and discrete elements method. The rail defects and the case of out-of-round wheels are considered. The dynamic interaction between the wheel-sets and the rail is accomplished by using the non-linear Hertzian model with hysteresis damping. A sensitivity analysis is done to evaluate the variables affecting more the maintenance costs. The rail-sleeper contact is assumed extended to an area-defined contact zone, rather than a single-point assumption which fits better real case studies. Experimental validations show how prediction fits well experimental data.

Enhanced expression of IL-8 in normal human keratinocytes and human keratinocyte cell line HaCaT in vitro after stimulation with contact sensitizers, tolerogens and irritants.

PubMed

Mohamadzadeh, M; Müller, M; Hultsch, T; Enk, A; Saloga, J; Knop, J

1994-12-01

To investigate the interleukin-8 production of keratinocytes after stimulation in vitro we have used various agents: (i) contact sensitizer (2,4-dinitrofluorobenzene, 3-n-pentadecylcatechol); (ii) tolerogen (5-methyl-3-n-pentadecylcatechol); (iii) irritant (sodium lauryl sulfate). Interleukin-8 gene expression was assessed by northern blot hybridization of the total cytoplasmic RNA extracted from subconfluent normal human keratinocyte cultures and the keratinocyte cell line HaCaT using a radiolabeled DNA probe specific for human interleukin-8. Interleukin-8 gene expression was markedly increased upon in vitro stimulation after 1-6 h with contact sensitizers, tolerogen and the irritant. In contrast, interleukin-8 production was not detectable in unstimulated normal human keratinocytes or the HaCaT keratinocyte cell line. These results suggest that the induction and production of interleukin-8 is a response to nonspecific stimuli and may play a critical role in the early response to immunogenic or inflammatory signals in man.

Prevalence and Clinical Correlates of Hypothyroidism in a School for Children with Mental Retardation

ERIC Educational Resources Information Center

Jaswal, Shivani; Kaur, Jasbinder; Chavan, B. S.; Gupta, Seema; Kaur, Harjeet

2011-01-01

Objective: Pediatrician is the first contact in the Pathway to Care in children with Mental retardation (MR). Following the recent advancements in the area of molecular genetics, understanding of specific conditions of MR or Developmental Delay (DD) is expanding. Hypothyroidism is a treatable metabolic/endocrinological cause of MR. The aim of this…

Pesticides: Improvements Needed To Ensure the Safety of Farmworkers and Their Children. Report to Congressional Requesters.

ERIC Educational Resources Information Center

Guerrero, Peter F.

In response to a Congressional request, the General Accounting Office examined issues related to pesticide safety for children in agricultural settings. Pesticides can cause acute, chronic, or delayed-onset illnesses. Children may be exposed to pesticides through farm work; eating pesticide-treated foods; or contact with drift from pesticide…

Susceptibility of Trogoderma granarium Everts and Trogoderma inclusum LeConte (Coleoptera: Dermestidae) to residual contact insecticides

USDA-ARS?s Scientific Manuscript database

Two pyrethroid insecticides were evaluated on concrete arenas for their efficacy against Trogoderma granarium and T. inclusum larvae. Ten larvae of either species were exposed to treated arenas for 1, 2, 3, and 7 d then transferred into 175 ml cups with diet for 30 d to evaluate delayed mortality. I...

Encapsulation of a model compound in pectin delays its release from a biobased polymeric material

USDA-ARS?s Scientific Manuscript database

A model compound was encapsulated in pectin and then extruded with thermoplastic starch to form a composite. The intended product was a food-contact tray made of biobased polymers infused with an anti-microbial agent; however, caffeine was used as the model compound in the preliminary work. The mode...

An update on airborne contact dermatitis.

PubMed

Huygens, S; Goossens, A

2001-01-01

This review is an update of 2 previously published articles on airborne contact dermatoses. Because reports in the literature often omit the term 'airborne', 18 volumes of Contact Dermatitis (April 1991-June 2000), 8 volumes of the American Journal of Contact Dermatitis (1992 1999) and 4 volumes of La Lettre du Gerda (1996-1999) were screened, and the cases cited were classified as to history, lesion locations, sensitization sources, and other factors. Reports on airborne dermatitis are increasingly being published, sometimes in relation to specific occupational areas.

Allergic Contact Dermatitis to Ophthalmic Medications: Relevant Allergens and Alternative Testing Methods.

PubMed

Grey, Katherine R; Warshaw, Erin M

Allergic contact dermatitis is an important cause of periorbital dermatitis. Topical ophthalmic agents are relevant sensitizers. Contact dermatitis to ophthalmic medications can be challenging to diagnose and manage given the numerous possible offending agents, including both active and inactive ingredients. Furthermore, a substantial body of literature reports false-negative patch test results to ophthalmic agents. Subsequently, numerous alternative testing methods have been described. This review outlines the periorbital manifestations, causative agents, and alternative testing methods of allergic contact dermatitis to ophthalmic medications.

Exploring the mango-poison ivy connection: the riddle of discriminative plant dermatitis.

PubMed

Hershko, Klilah; Weinberg, Ido; Ingber, Arieh

2005-01-01

A relationship between sensitivity to poison oak or poison ivy and mango dermatitis has been suggested by previous publications. The observation that acute allergic contact dermatitis can arise on first exposure to mango in patients who have been sensitized beforehand by contact with other urushiol-containing plants has been documented previously. We report 17 American patients employed in mango picking at a summer camp in Israel, who developed a rash of varying severity. All patients were either in contact with poison ivy/oak in the past or lived in areas where these plants are endemic. None recalled previous contact with mango. In contrast, none of their Israeli companions who had never been exposed to poison ivy/oak developed mango dermatitis. These observations suggest that individuals with known history of poison ivy/oak allergy, or those residing in area where these plants are common, may develop allergic contact dermatitis from mango on first exposure. We hypothesize that previous oral exposure to urushiol in the local Israeli population might establish immune tolerance to these plants.

Polyvinylidene fluoride (PVDF) vibration sensor for stethoscope and contact microphones

NASA Astrophysics Data System (ADS)

Toda, Minoru; Thompson, Mitchell

2005-09-01

This paper describes a new type of contact vibration sensor made by bonding piezoelectric PVDF film to a curved frame structure. The concave surface of the film is bonded to a rubber piece having a front contact face. Vibration is transmitted from this face through the rubber to the surface of the PVDF film. Pressure normal to the surface of the film is converted to circumferential strain, and an electric field is induced by the piezoelectric effect. The frequency response of the device was measured using an accelerometer mounted between the rubber face and a rigid vibration exciter plate. Sensitivity (voltage per unit displacement) was deduced from the device output and measured acceleration. The sensitivity was flat from 16 Hz to 3 kHz, peaking at 6 kHz due to a structural resonance. Calculations predicting performance against human tissue (stethoscope or contact microphone) show results similar to data measured against the metal vibrator. This implies that an accelerometer can be used for calibrating a stethoscope or contact microphone. The observed arterial pulse waveform showed more low-frequency content than a conventional electronic stethoscope.

Comparing maximum intercuspal contacts of virtual dental patients and mounted dental casts.

PubMed

Delong, Ralph; Ko, Ching-Chang; Anderson, Gary C; Hodges, James S; Douglas, W H

2002-12-01

Quantitative measures of occlusal contacts are of paramount importance in the study of chewing dysfunction. A tool is needed to identify and quantify occlusal parameters without occlusal interference caused by the technique of analysis. This laboratory simulation study compared occlusal contacts constructed from 3-dimensional images of dental casts and interocclusal records with contacts found by use of conventional methods. Dental casts of 10 completely dentate adults were mounted in a semi-adjustable Denar articulator. Maximum intercuspal contacts were marked on the casts using red film. Intercuspal records made with an experimental vinyl polysiloxane impression material recorded maximum intercuspation. Three-dimensional virtual models of the casts and interocclusal records were made using custom software and an optical scanner. Contacts were calculated between virtual casts aligned manually (CM), aligned with interocclusal records scanned seated on the mandibular casts (C1) or scanned independently (C2), and directly from virtual interocclusal records (IR). Sensitivity and specificity calculations used the marked contacts as the standard. Contact parameters were compared between method pairs. Statistical comparisons used analysis of variance and the Tukey-Kramer post hoc test (P=<.05). Sensitivities (range 0.76-0.89) did not differ significantly among the 4 methods (P=.14); however, specificities (range 0.89-0.98) were significantly lower for IR (P=.0001). Contact parameters of methods CM, C1, and C2 differed significantly from those of method IR (P<.02). The ranking based on method pair comparisons was C2/C1 > CM/C1 = CM/C2 > C2/IR > CM/IR > C1/IR, where ">" means "closer than." Within the limits of this study, occlusal contacts calculated from aligned virtual casts accurately reproduce articulator contacts.

Delayed transfer from hospital to community settings: the older person's perspective.

PubMed

Swinkels, Annette; Mitchell, Theresa

2009-02-01

Prevention and management of delayed transfer of older people from hospital to community settings is an enduring issue in industrialised societies and is the subject of many recent policies in the United Kingdom. A deeper, evidence-based understanding of the complex organizational and interprofessional issues which contribute to delays in transfer has emerged in recent years. Despite this, and the relative success of recent policies, two recent reviews of the area highlight the lack of studies on patients' perspectives. We sought to address this deficit by using conversational interviews and a phenomenological approach to explore and interpret participants' perceptions of delayed transfer from hospital into the community. A purposive sampling strategy was employed to incorporate participants from different categories of delay identified on weekly Situation Reports. Participants aged 65 years and over (mean age 82 +/- 5.4 years) and with a mean delay of 32 days (+/- 26) were recruited from three hospitals based in two NHS Trusts in the South of England. This paper focuses on their perceptions of the effects of delayed transfer into the community, their involvement in discharge planning and future community care needs. Our findings show that participants actively or passively relinquished their involvement in the processes of discharge planning because of the perceived expertise of others and also feelings of disempowerment secondary to poor health, low mood, dependency, lack of information and the intricacies of discharge planning processes for complex community care needs. Participants expressed a longing for continuity, emphasised the importance of social contact and sometimes appeared unrealistic about their future care needs. While current policies may have helped reduce overall numbers of delayed patients in the UK, our study suggests that there is scope for improvement in the involvement of delayed patients in planning their discharge into the community.

Fragrances and other materials in deodorants: search for potentially sensitizing molecules using combined GC-MS and structure activity relationship (SAR) analysis.

PubMed

Rastogi, S C; Lepoittevin, J P; Johansen, J D; Frosch, P J; Menné, T; Bruze, M; Dreier, B; Andersen, K E; White, I R

1998-12-01

Deodorants are one of the most frequently-used types of cosmetics and are a source of allergic contact dermatitis. Therefore, a gas chromatography - mass spectrometric analysis of 71 deodorants was performed for identification of fragrance and non-fragrance materials present in marketed deodorants. Futhermore, the sensitizing potential of these molecules was evaluated using structure activity relationships (SARs) analysis. This was based on the presence of 1 or more chemically reactive site(s), in the chemical structure, associated with sensitizing potential. Among the many different substances used to formulate cosmetic products (over 3500), 226 chemicals were identified in a sample of 71 deodorants. 84 molecules were found to contain at least 1 structural alert, and 70 to belong to, or be susceptible to being metabolized into, the chemical group of aldehydes, ketones and alpha,beta-unsaturated aldehydes, ketone or esters. The combination of GC-MS and SARs analysis could be helpful in the selection of substances for supplementary investigations regarding sensitizing properties. Thus, it may be a valuable tool in the management of contact allergy to deodorants and for producing new deodorants with decreased propensity to cause contact allergy.

The effects of resonances on time delay estimation for water leak detection in plastic pipes

NASA Astrophysics Data System (ADS)

Almeida, Fabrício C. L.; Brennan, Michael J.; Joseph, Phillip F.; Gao, Yan; Paschoalini, Amarildo T.

2018-04-01

In the use of acoustic correlation methods for water leak detection, sensors are placed at pipe access points either side of a suspected leak, and the peak in the cross-correlation function of the measured signals gives the time difference (delay) between the arrival times of the leak noise at the sensors. Combining this information with the speed at which the leak noise propagates along the pipe, gives an estimate for the location of the leak with respect to one of the measurement positions. It is possible for the structural dynamics of the pipe system to corrupt the time delay estimate, which results in the leak being incorrectly located. In this paper, data from test-rigs in the United Kingdom and Canada are used to demonstrate this phenomenon, and analytical models of resonators are coupled with a pipe model to replicate the experimental results. The model is then used to investigate which of the two commonly used correlation algorithms, the Basic Cross-Correlation (BCC) function or the Phase Transform (PHAT), is more robust to the undesirable structural dynamics of the pipe system. It is found that time delay estimation is highly sensitive to the frequency bandwidth over which the analysis is conducted. Moreover, it is found that the PHAT is particularly sensitive to the presence of resonances and can give an incorrect time delay estimate, whereas the BCC function is found to be much more robust, giving a consistently accurate time delay estimate for a range of dynamic conditions.

"What time is my next meal?" delay-discounting individuals choose smaller portions under conditions of uncertainty.

PubMed

Zimmerman, Annie R; Ferriday, Danielle; Davies, Sarah R; Martin, Ashley A; Rogers, Peter J; Mason, Alice; Brunstrom, Jeffrey M

2017-09-01

'Dietary' delay discounting is typically framed as a trade-off between immediate rewards and long-term health concerns. Our contention is that prospective thinking also occurs over shorter periods, and is engaged to select portion sizes based on the interval between meals (inter-meal interval; IMI). We sought to assess the extent to which the length of an IMI influences portion-size selection. We predicted that delay discounters would show 'IMI insensitivity' (relative lack of concern about hunger or fullness between meals). In particular, we were interested in participants' sensitivity to an uncertain IMI. We hypothesized that when meal times were uncertain, delay discounters would be less responsive and select smaller portion sizes. Participants (N = 90) selected portion sizes for lunch. In different trials, they were told to expect dinner at 5pm, 9pm, and either 5pm or 9pm (uncertain IMI). Individual differences in future-orientation were measured using a monetary delay-discounting task. Participants chose larger portions when the IMI was longer (p < 0.001). When the IMI was uncertain, delay-discounting participants chose smaller portions than the average portion chosen in the certain IMIs (p < 0.05). Furthermore, monetary discounting mediated a relationship between BMI and smaller portion selection in uncertainty (p < 0.05). This is the first study to report an association between delay discounting and IMI insensitivity. We reason that delay discounters selected smaller portions because they were less sensitive to the uncertain IMI, and overlooked concerns about potential future hunger. These findings are important because they illustrate that differences in discounting are expressed in short-term portion-size decisions and suggest that IMI insensitivity increases when meal timings are uncertain. Further research is needed to confirm whether these findings generalise to other populations. Copyright © 2017. Published by Elsevier Ltd.

Stabilizing skateboard speed-wobble with reflex delay.

PubMed

Varszegi, Balazs; Takacs, Denes; Stepan, Gabor; Hogan, S John

2016-08-01

A simple mechanical model of the skateboard-skater system is analysed, in which the effect of human control is considered by means of a linear proportional-derivative (PD) controller with delay. The equations of motion of this non-holonomic system are neutral delay-differential equations. A linear stability analysis of the rectilinear motion is carried out analytically. It is shown how to vary the control gains with respect to the speed of the skateboard to stabilize the uniform motion. The critical reflex delay of the skater is determined as the function of the speed. Based on this analysis, we present an explanation for the linear instability of the skateboard-skater system at high speed. Moreover, the advantages of standing ahead of the centre of the board are demonstrated from the viewpoint of reflex delay and control gain sensitivity. © 2016 The Author(s).

Pathways to multidrug-resistant tuberculosis diagnosis and treatment initiation: a qualitative comparison of patients' experiences in the era of rapid molecular diagnostic tests.

PubMed

Naidoo, Pren; van Niekerk, Margaret; du Toit, Elizabeth; Beyers, Nulda; Leon, Natalie

2015-10-28

Although new molecular diagnostic tests such as GenoType MTBDRplus and Xpert® MTB/RIF have reduced multidrug-resistant tuberculosis (MDR-TB) treatment initiation times, patients' experiences of diagnosis and treatment initiation are not known. This study aimed to explore and compare MDR-TB patients' experiences of their diagnostic and treatment initiation pathway in GenoType MTBDRplus and Xpert® MTB/RIF-based diagnostic algorithms. The study was undertaken in Cape Town, South Africa where primary health-care services provided free TB diagnosis and treatment. A smear, culture and GenoType MTBDRplus diagnostic algorithm was used in 2010, with Xpert® MTB/RIF phased in from 2011-2013. Participants diagnosed in each algorithm at four facilities were purposively sampled, stratifying by age, gender and MDR-TB risk profiles. We conducted in-depth qualitative interviews using a semi-structured interview guide. Through constant comparative analysis we induced common and divergent themes related to symptom recognition, health-care access, testing for MDR-TB and treatment initiation within and between groups. Data were triangulated with clinical information and health visit data from a structured questionnaire. We identified both enablers and barriers to early MDR-TB diagnosis and treatment. Half the patients had previously been treated for TB; most recognised recurring symptoms and reported early health-seeking. Those who attributed symptoms to other causes delayed health-seeking. Perceptions of poor public sector services were prevalent and may have contributed both to deferred health-seeking and to patient's use of the private sector, contributing to delays. However, once on treatment, most patients expressed satisfaction with public sector care. Two patients in the Xpert® MTB/RIF-based algorithm exemplified its potential to reduce delays, commencing MDR-TB treatment within a week of their first health contact. However, most patients in both algorithms experienced substantial delays. Avoidable health system delays resulted from providers not testing for TB at initial health contact, non-adherence to testing algorithms, results not being available and failure to promptly recall patients with positive results. Whilst the introduction of rapid tests such as Xpert® MTB/RIF can expedite MDR-TB diagnosis and treatment initiation, the full benefits are unlikely to be realised without reducing delays in health-seeking and addressing the structural barriers present in the health-care system.

The Effects of Methylphenidate on Discounting of Delayed Rewards in ADHD

PubMed Central

Shiels, Keri; Hawk, Larry W.; Reynolds, Brady; Mazzullo, Rebecca; Rhodes, Jessica; Pelham, William E.; Waxmonsky, James G.; Gangloff, Brian P.

2010-01-01

Impulsivity is a central component of attention-deficit/hyperactivity disorder (ADHD). Delay discounting, or a preference for smaller, immediate rewards over larger, delayed rewards is considered an important aspect of impulsivity, and delay-related impulsivity has been emphasized in etiological models of ADHD. The current study examined whether stimulant medication, an effective treatment for ADHD, reduces discounting of delayed experiential and hypothetical rewards among 49 children (age 9–12 years) with ADHD. Following a practice day, participants completed a 3-day double-blind placebo-controlled acute medication assessment. Active doses were long-acting methylphenidate (Concerta), with the nearest equivalents of 0.3 and 0.6 mg/kg TID immediate-release methylphenidate. On each testing day, participants completed experiential (real-world money in real time) and hypothetical discounting tasks. Relative to placebo, methylphenidate reduced discounting of delayed experiential rewards, but not hypothetical rewards. Broadly consistent with etiological models that emphasize delay-related impulsivity among children with ADHD, these findings provide initial evidence that stimulant medication reduces delay discounting among those with the disorder. The present results also draw attention to task parameters that may influence the sensitivity of various delay discounting measures to medication effects. PMID:19803628

Measles outbreak associated with an arriving refugee - Los Angeles County, California, August-September 2011.

PubMed

2012-06-01

Measles is a highly communicable, acute viral illness with potential for severe complications, including death. Although endemic measles was eliminated in the United States in 2000 as a result of widespread vaccination, sporadic measles outbreaks still occur, largely associated with international travel from measles-endemic countries and pockets of unvaccinated persons. On August 26, 2011, the Los Angeles County Department of Public Health (LACDPH) was notified of suspected measles in a refugee from Burma who had arrived in Los Angeles, California, on August 24, after a flight from Kuala Lumpur, Malaysia. Passengers on the flight included 31 other refugees who then traveled to seven other states, widening the measles investigation and response activities. In California alone, 50 staff members from LACDPH and the California Department of Public Health (CDPH) interviewed and reinterviewed 298 contacts. Measles was diagnosed in three contacts of the index patient (patient A). The three contacts with measles were two passengers on the same flight as patient A and a customs worker; no secondary cases were identified. Delayed diagnosis of measles in patient A and delayed notification of health officials precluded use of measles-mumps-rubella (MMR) vaccine as an outbreak intervention. This outbreak emphasizes the importance of maintaining a high level of vaccination coverage and continued high vigilance for measles in the United States, particularly among incoming international travelers; clinicians should immediately isolate persons with suspected measles and promptly report them to health authorities.

Sensitivity to external signals and synchronization properties of a non-isochronous auto-oscillator with delayed feedback

PubMed Central

Tiberkevich, Vasil S.; Khymyn, Roman S.; Tang, Hong X.; Slavin, Andrei N.

2014-01-01

For auto-oscillators of different nature (e.g. active cells in a human heart under the action of a pacemaker, neurons in brain, spin-torque nano-oscillators, micro and nano-mechanical oscillators, or generating Josephson junctions) a critically important property is their ability to synchronize with each other. The synchronization properties of an auto oscillator are directly related to its sensitivity to external signals. Here we demonstrate that a non-isochronous (having generation frequency dependent on the amplitude) auto-oscillator with delayed feedback can have an extremely high sensitivity to external signals and unusually large width of the phase-locking band near the boundary of the stable auto-oscillation regime. This property could be used for the development of synchronized arrays of non-isochronous auto-oscillators in physics and engineering, and, for instance, might bring a better fundamental understanding of ways to control a heart arrythmia in medicine. PMID:24464086

Generation of helical gears with new surfaces topology by application of CNC machines

NASA Technical Reports Server (NTRS)

Litvin, F. L.; Chen, N. X.; Hsiao, C. L.; Handschuh, Robert F.

1993-01-01

Analysis of helical involute gears by tooth contact analysis shows that such gears are very sensitive to angular misalignment that leads to edge contact and the potential for high vibration. A new topology of tooth surfaces of helical gears that enables a favorable bearing contact and a reduced level of vibration is described. Methods for grinding of the helical gears with the new topology are proposed. A TCA (tooth contact analysis) program for simulation of meshing and contact of helical gears with the new topology has been developed. Numerical examples that illustrate the proposed ideas are discussed.

Generation of helical gears with new surfaces, topology by application of CNC machines

NASA Technical Reports Server (NTRS)

Litvin, F. L.; Chen, N. X.; Hsiao, C. L.; Handschuh, R. F.

1993-01-01

Analysis of helical involute gears by tooth contact analysis shows that such gears are very sensitive to angular misalignment that leads to edge contact and the potential for high vibration. A new topology of tooth surfaces of helical gears that enables a favorable bearing contact and a reduced level of vibration is described. Methods for grinding of the helical gears with the new topology are proposed. A TCA (tooth contact analysis) program for simulation of meshing and contact of helical gears with the new topology has been developed. Numerical examples that illustrate the proposed ideas are discussed.

Association between pet ownership and the sensitization to pet allergens in adults with various allergic diseases.

PubMed

Park, Yong-Bum; Mo, Eun-Kyung; Lee, Jae-Young; Kim, Joo-Hee; Kim, Cheol-Hong; Hyun, In-Gyu; Choi, Jeong-Hee

2013-09-01

As pet ownership increases, sensitization to animal allergens due to domestic exposure is a concern. Sensitization to animal allergens may occur from indirect exposure, as well as direct ownership of animals. However, there have been conflicting results regarding the association between pet ownership and sensitization to animal allergens in adults. In total, 401 patients with various allergic diseases were enrolled in this study. We performed skin prick tests with 55 common inhalant and food allergens, including dog, cat, and rabbit allergens. A mean wheal diameter of 3 mm or greater was considered a positive reaction. The exposure modality to each animal allergen was investigated using a questionnaire and included present ownership, past ownership, occupational exposure, occasional exposure, contact with pet owner, and no contact. Present ownership, past ownership, occupational, and occasional exposure were regarded as direct exposure. The sensitization rate for animal allergens was 20.4% for dog, 15.0% for cat, and 9.0% for rabbit. Direct exposure to dogs (72.0%) was significantly higher than that of other animals (18.4% for cats and 16.7% for rabbits), whereas 'no contact' with cats (78.3%) and rabbits (83.3%) was significantly higher than with dogs (26.8%; P<0.0001). Independent risk factors for sensitization to animal allergens were sensitization to Dermatophagoides pteronyssinus (OR=2.4, P=0.052), Dermatophagoides farinae (OR=5.1, P<0.001), cat (OR=4.4, P<0.0001), and direct exposure to dogs (OR=1.5, P=0.029) for dog, and sensitization to dog (OR=4.4, P<0.0001) and rabbit (OR=2.6, P=0.036) for cats. Finally, for rabbits, the independent risk factor was sensitization to Alternaria (OR=6.0, P<0.002). These results suggest that direct exposure to dogs contributes to the sensitization to dog allergens in patients with allergic diseases, whereas indirect exposure to cats and rabbits may induce sensitization to each animal's allergen.

Comparative evaluation of e-beam sensitive chemically amplified resists for mask making

NASA Astrophysics Data System (ADS)

Irmscher, Mathias; Beyer, Dirk; Butschke, Joerg; Constantine, Chris; Hoffmann, Thomas; Koepernik, Corinna; Krauss, Christian; Leibold, Bernd; Letzkus, Florian; Mueller, Dietmar; Springer, Reinhard; Voehringer, Peter

2002-07-01

Positive tone chemically amplified resists CAP209, EP012M (TOK), KRS-XE (JSR) and FEP171 (Fuji) were evaluated for mask making. The investigations were performed on an advanced tool set comprising of a Steag coater ASR5000, Steag developer ASP5000, 50kV e-beam writer Leica SB350, UNAXIS MASK ETCHER III , STS ICP silicon etcher and a CD-SEM KLA8100. We investigated and compared resolution, sensitivity, resist slope, dark field loss, CD-uniformity, line edge roughness, and etch resistance of the evaluated resists. Furthermore, the influence of post coating delay, post exposure delay and other process parameters on the resist performance was determined.

Parameter estimation and sensitivity analysis for a mathematical model with time delays of leukemia

NASA Astrophysics Data System (ADS)

Cândea, Doina; Halanay, Andrei; Rǎdulescu, Rodica; Tǎlmaci, Rodica

2017-01-01

We consider a system of nonlinear delay differential equations that describes the interaction between three competing cell populations: healthy, leukemic and anti-leukemia T cells involved in Chronic Myeloid Leukemia (CML) under treatment with Imatinib. The aim of this work is to establish which model parameters are the most important in the success or failure of leukemia remission under treatment using a sensitivity analysis of the model parameters. For the most significant parameters of the model which affect the evolution of CML disease during Imatinib treatment we try to estimate the realistic values using some experimental data. For these parameters, steady states are calculated and their stability is analyzed and biologically interpreted.

[Orthopedic surgical implants and allergies. Joint statement by the Implant Allergy Working Group (AK 20) of the DGOOC (German Association of Orthopedics and Orthopedic Surgery), DKG (German Contact Dermatitis Research Group) and DGAKI (German Society for Allergology and Clinical Immunology)].

PubMed

Thomas, P; Schuh, A; Ring, J; Thomsen, M

2008-03-01

Materials used in osteosynthesis or artificial joint replacement are usually well tolerated. Complaints after such operations are mostly related to infection or mechanical problems but may also be caused by allergic reactions. The latter encompass skin changes, e.g., eczema, delayed wound/bone healing, recurrent effusion, pain, or implant loosening. In contrast to the high incidence of cutaneous metal contact allergy, allergies associated with implants are a rare condition. However, epidemiological data on the incidence of implant-related allergic reactions are still missing. Typical elicitors are nickel, chromium, cobalt, and constituents of bone cement (acrylates und additives such as gentamicin or benzoyl peroxide). After exclusion of the most common differential diagnoses, allergy diagnostic procedures are primarily based on patch tests including a metal and bone cement component series. Additional analysis of periimplant tissue is recommended. However, further studies are necessary to show the significance of the histologic findings and the role of the lymphocyte transformation test (LTT). Which combinations of factors will induce allergic sensitization to implants or trigger periimplant allergic reactions in the case of preexisting cutaneous metal allergy is still unknown. Titanium-based osteosynthesis materials are recommended for metal allergic patients. In elective hip replacements, a ceramic/polyethylene (PE) articulation should be used, and in knee replacements "alternative materials". If a regular, potentially applicable CoCr/PE articulation is preferred, the patient must be well informed and must give his/her written consent.

Sensitization and cross-reactivity patterns of contact allergy to diisocyanates and corresponding amines: investigation of diphenylmethane-4,4'-diisocyanate, diphenylmethane-4,4'-diamine, dicyclohexylmethane-4,4'-diisocyanate, and dicylohexylmethane-4,4'-diamine.

PubMed

Hamada, Haneen; Bruze, Magnus; Zimerson, Erik; Isaksson, Marléne; Engfeldt, Malin

2017-10-01

Isocyanates are used in polyurethane production. Dermal exposure to isocyanates can induce contact allergy. The most common isocyanate is diphenylmethane diisocyanate used for industrial purposes. The isomer diphenylmethane-4,4'-diisocyanate (4,4'-MDI) is used in patch testing. Diphenylmethane-4,4'-diamine (4,4'-MDA) is its corresponding amine. Concurrent reactions to 4,4'-MDI and 4,4'-MDA have been reported, as have concurrent reactions to 4,4'-MDI and dicyclohexylmethane-4,4'-diisocyanate (4,4'-DMDI). To investigate the sensitization capacities and the cross-reactivity of 4,4'-MDI, 4,4'-MDA, 4,4'-DMDI, and dicyclohexylmethane-4,4'-diamine (4,4'-DMDA). The guinea-pig maximization test (GPMT) was used. The GPMT showed sensitizing capacities for all investigated substances: 4,4'-MDI, 4,4'-MDA, 4,4'-DMDI, and 4,4'-DMDA (all p < 0.001). 4,4'-MDI-sensitized animals showed cross-reactivity to 4,4'-MDA (p < 0.001) and 4,4'-DMDI (all p < 0.05). 4,4'-MDA-sensitized animals showed cross-reactivity to 4,4'-DMDA (p = 0.008). All of the investigated substances were shown to be strong sensitizers. Animals sensitized to 4,4'-MDI showed cross-reactivity to 4,4'-MDA and 4,4'-DMDI, supporting previous findings in the literature. The aromatic amine 4,4'-MDA showed cross-reactivity to the aliphatic amine 4,4'-DMDA. © 2017 The Authors. Contact Dermatitis published by John Wiley & Sons Ltd.

Delays reducing waterborne and water-related infectious diseases in China under climate change

PubMed Central

Hodges, Maggie; Belle, Jessica H.; Carlton, Elizabeth J.; Liang, Song; Li, Huazhong; Luo, Wei; Freeman, Matthew C.; Liu, Yang; Gao, Yang; Hess, Jeremy J.; Remais, Justin V.

2014-01-01

Despite China’s rapid progress improving water, sanitation and hygiene (WSH) access, in 2011, 471 million people lacked access to improved sanitation and 401 million to household piped water. Because certain infectious diseases are sensitive to changes in both climate and WSH conditions, we projected impacts of climate change on WSH-attributable diseases in China in 2020 and 2030 by coupling estimates of the temperature sensitivity of diarrheal diseases and three vector-borne diseases, temperature projections from global climate models, WSH-infrastructure development scenarios, and projected demographic changes. By 2030, climate change is projected to delay China’s rapid progress toward reducing WSH-attributable infectious disease burden by 8–85 months. This development delay summarizes the adverse impact of climate change on WSH-attributable infectious diseases in China, and can be used in other settings where a significant health burden may accompany future changes in climate even as the total burden of disease falls due to non-climate reasons. PMID:25530812

Sensitivity of a mesoscale model to initial specification of relative humidity, liquid water and vertical motion

NASA Technical Reports Server (NTRS)

Kalb, M. W.; Perkey, D. J.

1985-01-01

The influence of synoptic scale initial conditions on the accuracy of mesoscale precipitation modeling is investigated. Attention is focused on the relative importance of the water vapor, cloud water, rain water, and vertical motion, with the analysis carried out using the Limited Area Mesoscale Prediction System (LAMPS). The fully moist primitive equation model has 15 levels and a terrain-following sigma coordinate system. A K-theory approach was implemented to model the planetary boundary layer. A total of 15 sensitivity simulations were run to investigate the effects of the synoptic initial conditions of the four atmospheric variables. The absence of synoptic cloud and rain water amounts in the initialization caused a 2 hr delay in the onset of precipitation. The delay was increased if synoptic-scale vertical motion was used instead of mesoscale values. Both the delays and a choice of a smoothed moisture field resulted in underestimations of the total rainfall.

Asymmetric noise sensitivity of pulse trains in an excitable microlaser with delayed optical feedback

NASA Astrophysics Data System (ADS)

Terrien, Soizic; Krauskopf, Bernd; Broderick, Neil G. R.; Andréoli, Louis; Selmi, Foued; Braive, Rémy; Beaudoin, Grégoire; Sagnes, Isabelle; Barbay, Sylvain

2017-10-01

A semiconductor micropillar laser with delayed optical feedback is considered. In the excitable regime, we show that a single optical perturbation can trigger a train of pulses that is sustained for a finite duration. The distribution of the pulse train duration exhibits an exponential behavior characteristic of a noise-induced process driven by uncorrelated white noise present in the system. The comparison of experimental observations with theoretical and numerical analysis of a minimal model yields excellent agreement. Importantly, the random switch-off process takes place between two attractors of different nature: an equilibrium and a periodic orbit. Our analysis shows that there is a small time window during which the pulsations are very sensitive to noise, and this explains the observed strong bias toward switch-off. These results raise the possibility of all optical control of the pulse train duration that may have an impact for practical applications in photonics and may also apply to the dynamics of other noise-driven excitable systems with delayed feedback.

Delays in reducing waterborne and water-related infectious diseases in China under climate change

NASA Astrophysics Data System (ADS)

Hodges, Maggie; Belle, Jessica H.; Carlton, Elizabeth J.; Liang, Song; Li, Huazhong; Luo, Wei; Freeman, Matthew C.; Liu, Yang; Gao, Yang; Hess, Jeremy J.; Remais, Justin V.

2014-12-01

Despite China's rapid progress in improving water, sanitation and hygiene (WSH) access, in 2011, 471 million people lacked access to improved sanitation and 401 million to household piped water. As certain infectious diseases are sensitive to changes in both climate and WSH conditions, we projected impacts of climate change on WSH-attributable diseases in China in 2020 and 2030 by coupling estimates of the temperature sensitivity of diarrhoeal diseases and three vector-borne diseases, temperature projections from global climate models, WSH-infrastructure development scenarios, and projected demographic changes. By 2030, climate change is projected to delay China's rapid progress towards reducing WSH-attributable infectious disease burden by 8-85 months. This development delay summarizes the adverse impact of climate change on WSH-attributable infectious diseases in China, and can be used in other settings where a significant health burden may accompany future changes in climate even as the total burden of disease falls owing to non-climate reasons.

Delays reducing waterborne and water-related infectious diseases in China under climate change.

PubMed

Hodges, Maggie; Belle, Jessica H; Carlton, Elizabeth J; Liang, Song; Li, Huazhong; Luo, Wei; Freeman, Matthew C; Liu, Yang; Gao, Yang; Hess, Jeremy J; Remais, Justin V

2014-12-01

Despite China's rapid progress improving water, sanitation and hygiene (WSH) access, in 2011, 471 million people lacked access to improved sanitation and 401 million to household piped water. Because certain infectious diseases are sensitive to changes in both climate and WSH conditions, we projected impacts of climate change on WSH-attributable diseases in China in 2020 and 2030 by coupling estimates of the temperature sensitivity of diarrheal diseases and three vector-borne diseases, temperature projections from global climate models, WSH-infrastructure development scenarios, and projected demographic changes. By 2030, climate change is projected to delay China's rapid progress toward reducing WSH-attributable infectious disease burden by 8-85 months. This development delay summarizes the adverse impact of climate change on WSH-attributable infectious diseases in China, and can be used in other settings where a significant health burden may accompany future changes in climate even as the total burden of disease falls due to non-climate reasons.

Prediction of the contact sensitizing potential of chemicals using analysis of gene expression changes in human THP-1 monocytes.

PubMed

Arkusz, Joanna; Stępnik, Maciej; Sobala, Wojciech; Dastych, Jarosław

2010-11-10

The aim of this study was to find differentially regulated genes in THP-1 monocytic cells exposed to sensitizers and nonsensitizers and to investigate if such genes could be reliable markers for an in vitro predictive method for the identification of skin sensitizing chemicals. Changes in expression of 35 genes in the THP-1 cell line following treatment with chemicals of different sensitizing potential (from nonsensitizers to extreme sensitizers) were assessed using real-time PCR. Verification of 13 candidate genes by testing a large number of chemicals (an additional 22 sensitizers and 8 nonsensitizers) revealed that prediction of contact sensitization potential was possible based on evaluation of changes in three genes: IL8, HMOX1 and PAIMP1. In total, changes in expression of these genes allowed correct detection of sensitization potential of 21 out of 27 (78%) test sensitizers. The gene expression levels inside potency groups varied and did not allow estimation of sensitization potency of test chemicals. Results of this study indicate that evaluation of changes in expression of proposed biomarkers in THP-1 cells could be a valuable model for preliminary screening of chemicals to discriminate an appreciable majority of sensitizers from nonsensitizers. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Prospective analysis of delayed colorectal post-polypectomy bleeding.

PubMed

Park, Soo-Kyung; Seo, Jeong Yeon; Lee, Min-Gu; Yang, Hyo-Joon; Jung, Yoon Suk; Choi, Kyu Yong; Kim, Hungdai; Kim, Hyung Ook; Jung, Kyung Uk; Chun, Ho-Kyung; Park, Dong Il

2018-01-17

Although post-polypectomy bleeding is the most frequent complication after colonoscopic polypectomy, only few studies have investigated the incidence of bleeding prospectively. The aim of this study was to investigate the incidence of delayed post-polypectomy bleeding and its associated risk factors prospectively. Patients who underwent colonoscopic polypectomy at Kangbuk Samsung Hospital from January 2013 to December 2014 were prospectively enrolled in this study. Trained nurses contacted patients via telephone 7 and 30 days after polypectomy and completed a standardized questionnaire regarding the development of bleeding. Delayed post-polypectomy bleeding was categorized as minor or major and early or late bleeding. Major delayed bleeding was defined as a > 2-g/dL drop in the hemoglobin level, requiring hospitalization for control of bleeding or blood transfusion; late delayed bleeding was defined as bleeding occurring later than 24 h after polypectomy. A total of 8175 colonoscopic polypectomies were performed in 3887 patients. Overall, 133 (3.4%) patients developed delayed post-polypectomy bleeding. Among them, 90 (2.3%) and 43 (1.1%) patients developed minor and major delayed bleeding, respectively, and 39 (1.0%) patients developed late delayed bleeding. In the polyp-based multivariate analysis, young age (< 50 years; odds ratio [OR] 2.10; 95% confidence interval [CI] 1.18-3.68), aspirin use (OR 2.78; 95% CI 1.23-6.31), and polyp size of > 10 mm (OR 2.45; 95% CI 1.38-4.36) were significant risk factors for major delayed bleeding, while young age (< 50 years; OR 2.6; 95% CI 1.35-5.12) and immediate bleeding (OR 3.3; 95% CI 1.49-7.30) were significant risk factors for late delayed bleeding. Young age, aspirin use, polyp size, and immediate bleeding were found to be independent risk factors for delayed post-polypectomy bleeding.

The local lymph node assay and skin sensitization testing.

PubMed

Kimber, Ian; Dearman, Rebecca J

2010-01-01

The mouse local lymph node assay (LLNA) is a method for the identification and characterization of skin sensitization hazards. In this context the method can be used both to identify contact allergens, and also determine the relative skin sensitizing potency as a basis for derivation of effective risk assessments.The assay is based on measurement of proliferative responses by draining lymph node cells induced following topical exposure of mice to test chemicals. Such responses are known to be causally and quantitatively associated with the acquisition of skin sensitization and therefore provide a relevant marker for characterization of contact allergic potential.The LLNA has been the subject of exhaustive evaluation and validation exercises and has been assigned Organization for Economic Cooperation and Development (OECD) test guideline 429. Herein we describe the conduct and interpretation of the LLNA.

Contact sensitization in Dutch children and adolescents with and without atopic dermatitis - a retrospective analysis.

PubMed

Lubbes, Stefanie; Rustemeyer, Thomas; Sillevis Smitt, Johannes H; Schuttelaar, Marie Louise; Middelkamp-Hup, Maritza A

2017-03-01

Allergic contact dermatitis is known to occur in children with and without atopic dermatitis, but more data are needed on contact sensitization profiles in these two groups. To identify frequent allergens in children with and without atopic dermatitis suspected of having allergic contact dermatitis. A retrospective analysis of children aged 0-17 years patch tested between 1996 and 2013 was performed. Of all 1012 children tested because of suspected contact dermatitis, 46% developed one or more positive reactions, the proportions for children with (n = 526) and without (n = 395) atopic dermatitis being 48% and 47%, respectively. Children with atopic dermatitis reacted more often to lanolin alcohol (30% pet., p = 0.030), Amerchol L-101 (p = 0.030), and fragrances [fragrance mix I (p = 0.048) and Myroxylon pereirae (p = 0.005)]. Allergens outside the European baseline series that frequently gave positive reactions in these groups included cocamidopropyl betaine and Amerchol L-101. Reactivity to these allergens was significantly more common in atopic dermatitis children. Sensitization prevalences in children with and without atopic dermatitis were similar, but children with atopic dermatitis reacted significantly more often to lanolin alcohol and fragrances. Testing with additional series besides the European baseline series may be necessary, as reactions to, for example, cocamidopropyl betaine and Amerchol L-101 may otherwise be missed. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Uncertainty in Damage Detection, Dynamic Propagation and Just-in-Time Networks

DTIC Science & Technology

2015-08-03

estimated parameter uncertainty in dynamic data sets; high order compact finite difference schemes for Helmholtz equations with discontinuous wave numbers...delay differential equations with a Gamma distributed delay. We found that with the same population size the histogram plots for the solution to the...schemes for Helmholtz equations with discontinuous wave numbers across interfaces. • We carried out numerical sensitivity analysis with respect to

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

NASA Astrophysics Data System (ADS)

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.; Sirk, Martin; Muirhead, Philip S.; Muterspaugh, Matthew W.; Lloyd, James P.; Ishikawa, Yuzo; McDonald, Eliza A.; Shourt, William V.; Vanderburg, Andrew M.

2016-04-01

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the "TEDI" interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced by the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels-EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. A section on theoretical photon limited sensitivity is in a companion paper, part 2.

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

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

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the “TEDI” interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced bymore » the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels—EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. Lastly, a section on theoretical photon limited sensitivity is in a companion paper, part 2.« less

High-resolution broadband spectroscopy using externally dispersed interferometry at the Hale telescope: Part 1, data analysis and results

DOE PAGES

Erskine, David J.; Edelstein, Jerry; Wishnow, Edward H.; ...

2016-05-27

High-resolution broadband spectroscopy at near-infrared wavelengths (950 to 2450 nm) has been performed using externally dispersed interferometry (EDI) at the Hale telescope at Mt. Palomar. Observations of stars were performed with the “TEDI” interferometer mounted within the central hole of the 200-in. primary mirror in series with the comounted TripleSpec near-infrared echelle spectrograph. These are the first multidelay EDI demonstrations on starlight, as earlier measurements used a single delay or laboratory sources. We demonstrate very high (10×) resolution boost, from original 2700 to 27,000 with current set of delays (up to 3 cm), well beyond the classical limits enforced bymore » the slit width and detector pixel Nyquist limit. Significantly, the EDI used with multiple delays rather than a single delay as used previously yields an order of magnitude or more improvement in the stability against native spectrograph point spread function (PSF) drifts along the dispersion direction. We observe a dramatic (20×) reduction in sensitivity to PSF shift using our standard processing. A recently realized method of further reducing the PSF shift sensitivity to zero is described theoretically and demonstrated in a simple simulation which produces a 350× times reduction. We demonstrate superb rejection of fixed pattern noise due to bad detector pixels—EDI only responds to changes in pixel intensity synchronous to applied dithering. This part 1 describes data analysis, results, and instrument noise. Lastly, a section on theoretical photon limited sensitivity is in a companion paper, part 2.« less

Area 3a Neuron Response to Skin Nociceptor Afferent Drive

PubMed Central

Favorov, Oleg V.; Li, Yongbiao; Quibrera, Miguel; Tommerdahl, Mark

2009-01-01

Area 3a neurons are identified that respond weakly or not at all to skin contact with a 25–38 °C probe, but vigorously to skin contact with the probe at ≥49 °C. Maximal rate of spike firing associated with 1- to 7-s contact at ≥49 °C occurs 1-2 s after probe removal from the skin. The activity evoked by 5-s contact with the probe at 51 °C remains above-background for ∼20 s after probe retraction. After 1-s contact at 55–56 °C activity remains above-background for ∼4 s. Magnitude of spike firing associated with 5-s contact increases linearly as probe temperature is increased from 49–51 °C. Intradermal capsaicin injection elicits a larger (∼2.5×) and longer-lasting (100×) increase in area 3a neuron firing rate than 5-s contact at 51 °C. Area 3a neurons exhibit enhanced or novel responsivity to 25–38 °C contact for a prolonged time after intradermal injection of capsaicin or α, β methylene adenosine triphosphate. Their 1) delayed and persisting increase in spike firing in response to contact at ≥49 °C, 2) vigorous and prolonged response to intradermal capsaicin, and 3) enhanced and frequently novel response to 25–38 °C contact following intradermal algogen injection or noxious skin heating suggest that the area 3a neurons identified in this study contribute to second pain and mechanical hyperalgesia/allodynia. PMID:18534992

Use of an ex vivo local lymph node assay to assess contact hypersensitivity potential.

PubMed

Piccotti, Joseph R; Kawabata, Thomas T

2008-07-01

The local lymph node assay (LLNA) is used to assess the contact hypersensitivity potential of compounds. In the standard assay, mice are treated topically with test compound to the dorsum of both ears on Days 1-3. The induction of a hypersensitivity response is assessed on Day 6 by injecting [(3)H]-thymidine into a tail vein and measuring thymidine incorporation into DNA of lymph node cells draining the ears. The ex vivo LLNA is conducted similarly except lymphocyte proliferation is assessed after in vitro incubation of lymph node cells with [(3)H]-thymidine, which significantly reduces the amount of radioactive waste. The current study tested the use of this approach for hazard assessment of contact hypersensitivity and to estimate allergenic potency. Female BALB/c mice were treated on Days 1-3 with two nonsensitizers (4' -methoxyacetophenone, diethyl phthalate), three weak sensitizers (hydroxycitronellal, eugenol, citral), one weak-to-moderate sensitizer (hexylcinnamic aldehyde), two moderate sensitizers (isoeugenol, phenyl benzoate), and one strong sensitizer (dinitrochlorobenzene). On Day 6, isolated lymph node cells were incubated overnight with [(3)H]-thymidine and thymidine incorporation was measured by liquid scintillation spectrophotometry. The ex vivo LLNA accurately distinguished the contact sensitizers from the nonsensitizing chemicals, and correctly ranked the relative potency of the compounds tested. The EC3 values, i.e., the effective concentration of test substance needed to induce a stimulation index of 3, were as follows: 4' -methoxyacetophenone (> 50%), diethyl phthalate (> 50%), hydroxycitronellal (20.4%), eugenol (13.6%), citral (8.9%), isoeugenol (3.8%), hexylcinnamic aldehyde (2.7%), phenyl benzoate (2%), and dinitrochlorobenzene (0.02%). In addition, low inter-animal and inter-experiment variability was seen with 25% hexyl-cinnamic aldehyde (assay positive control). The results of the ex vivo LLNA in the current study were consistent with published reports using the standard LLNA and provided further evidence that supports the use of this alternative approach to assess the skin sensitization potential of test compounds.

Multicultural Experience and Intercultural Sensitivity among South Korean Adolescents

ERIC Educational Resources Information Center

Park, Jung-Suh

2013-01-01

This study examined experience with multicultural contact and the intercultural sensitivity of majority adolescents in South Korean society, one that is rapidly shifting toward a more multicultural environment. It also analyzed the influence of these multicultural experiences on intercultural sensitivity. The results of the analysis revealed a…

The Application of MRI for Depiction of Subtle Blood Brain Barrier Disruption in Stroke

PubMed Central

Israeli, David; Tanne, David; Daniels, Dianne; Last, David; Shneor, Ran; Guez, David; Landau, Efrat; Roth, Yiftach; Ocherashvilli, Aharon; Bakon, Mati; Hoffman, Chen; Weinberg, Amit; Volk, Talila; Mardor, Yael

2011-01-01

The development of imaging methodologies for detecting blood-brain-barrier (BBB) disruption may help predict stroke patient's propensity to develop hemorrhagic complications following reperfusion. We have developed a delayed contrast extravasation MRI-based methodology enabling real-time depiction of subtle BBB abnormalities in humans with high sensitivity to BBB disruption and high spatial resolution. The increased sensitivity to subtle BBB disruption is obtained by acquiring T1-weighted MRI at relatively long delays (~15 minutes) after contrast injection and subtracting from them images acquired immediately after contrast administration. In addition, the relatively long delays allow for acquisition of high resolution images resulting in high resolution BBB disruption maps. The sensitivity is further increased by image preprocessing with corrections for intensity variations and with whole body (rigid+elastic) registration. Since only two separate time points are required, the time between the two acquisitions can be used for acquiring routine clinical data, keeping the total imaging time to a minimum. A proof of concept study was performed in 34 patients with ischemic stroke and 2 patients with brain metastases undergoing high resolution T1-weighted MRI acquired at 3 time points after contrast injection. The MR images were pre-processed and subtracted to produce BBB disruption maps. BBB maps of patients with brain metastases and ischemic stroke presented different patterns of BBB opening. The significant advantage of the long extravasation time was demonstrated by a dynamic-contrast-enhancement study performed continuously for 18 min. The high sensitivity of our methodology enabled depiction of clear BBB disruption in 27% of the stroke patients who did not have abnormalities on conventional contrast-enhanced MRI. In 36% of the patients, who had abnormalities detectable by conventional MRI, the BBB disruption volumes were significantly larger in the maps than in conventional MRI. These results demonstrate the advantages of delayed contrast extravasation in increasing the sensitivity to subtle BBB disruption in ischemic stroke patients. The calculated disruption maps provide clear depiction of significant volumes of BBB disruption unattainable by conventional contrast-enhanced MRI. PMID:21209786

The application of MRI for depiction of subtle blood brain barrier disruption in stroke.

PubMed

Israeli, David; Tanne, David; Daniels, Dianne; Last, David; Shneor, Ran; Guez, David; Landau, Efrat; Roth, Yiftach; Ocherashvilli, Aharon; Bakon, Mati; Hoffman, Chen; Weinberg, Amit; Volk, Talila; Mardor, Yael

2010-12-26

The development of imaging methodologies for detecting blood-brain-barrier (BBB) disruption may help predict stroke patient's propensity to develop hemorrhagic complications following reperfusion. We have developed a delayed contrast extravasation MRI-based methodology enabling real-time depiction of subtle BBB abnormalities in humans with high sensitivity to BBB disruption and high spatial resolution. The increased sensitivity to subtle BBB disruption is obtained by acquiring T1-weighted MRI at relatively long delays (~15 minutes) after contrast injection and subtracting from them images acquired immediately after contrast administration. In addition, the relatively long delays allow for acquisition of high resolution images resulting in high resolution BBB disruption maps. The sensitivity is further increased by image preprocessing with corrections for intensity variations and with whole body (rigid+elastic) registration. Since only two separate time points are required, the time between the two acquisitions can be used for acquiring routine clinical data, keeping the total imaging time to a minimum. A proof of concept study was performed in 34 patients with ischemic stroke and 2 patients with brain metastases undergoing high resolution T1-weighted MRI acquired at 3 time points after contrast injection. The MR images were pre-processed and subtracted to produce BBB disruption maps. BBB maps of patients with brain metastases and ischemic stroke presented different patterns of BBB opening. The significant advantage of the long extravasation time was demonstrated by a dynamic-contrast-enhancement study performed continuously for 18 min. The high sensitivity of our methodology enabled depiction of clear BBB disruption in 27% of the stroke patients who did not have abnormalities on conventional contrast-enhanced MRI. In 36% of the patients, who had abnormalities detectable by conventional MRI, the BBB disruption volumes were significantly larger in the maps than in conventional MRI. These results demonstrate the advantages of delayed contrast extravasation in increasing the sensitivity to subtle BBB disruption in ischemic stroke patients. The calculated disruption maps provide clear depiction of significant volumes of BBB disruption unattainable by conventional contrast-enhanced MRI.

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

Contact Tracing during an Outbreak of Ebola Virus Disease in the Western Area Districts of Sierra Leone: Lessons for Future Ebola Outbreak Response.

PubMed

Olu, Olushayo Oluseun; Lamunu, Margaret; Nanyunja, Miriam; Dafae, Foday; Samba, Thomas; Sempiira, Noah; Kuti-George, Fredson; Abebe, Fikru Zeleke; Sensasi, Benjamin; Chimbaru, Alexander; Ganda, Louisa; Gausi, Khoti; Gilroy, Sonia; Mugume, James

2016-01-01

Contact tracing is a critical strategy required for timely prevention and control of Ebola virus disease (EVD) outbreaks. Available evidence suggests that poor contact tracing was a driver of the EVD outbreak in West Africa, including Sierra Leone. In this article, we answered the question as to whether EVD contact tracing, as practiced in Western Area (WA) districts of Sierra Leone from 2014 to 2015, was effective. The goal is to describe contact tracing and identify obstacles to its effective implementation. Mixed methods comprising secondary data analysis of the EVD case and contact tracing data sets collected from WA during the period from 2014 to 2015, key informant interviews of contact tracers and their supervisors, and a review of available reports on contact tracing were implemented to obtain data for this study. During the study period, 3,838 confirmed cases and 32,706 contacts were listed in the viral hemorrhagic fever and contact databases for the district (mean 8.5 contacts per case). Only 22.1% (852) of the confirmed cases in the study area were listed as contacts at the onset of their illness, which indicates incomplete identification and tracing of contacts. Challenges associated with effective contact tracing included lack of community trust, concealing of exposure information, political interference with recruitment of tracers, inadequate training of contact tracers, and incomplete EVD case and contact database. While the tracers noted the usefulness of community quarantine in facilitating their work, they also reported delayed or irregular supply of basic needs, such as food and water, which created resistance from the communities. Multiple gaps in contact tracing attributed to a variety of factors associated with implementers, and communities were identified as obstacles that impeded timely control of the EVD outbreak in the WA of Sierra Leone. In future outbreaks, early community engagement and participation in contact tracing, establishment of appropriate mechanisms for selection, adequate training and supervision of qualified contact tracers, establishment of a well-managed and complete contact tracing database, and provision of basic needs to quarantined contacts are recommended as measures to enhance effective contact tracing.

Acrylate and methacrylate contact allergy and allergic contact disease: a 13-year review.

PubMed

Spencer, Ashley; Gazzani, Paul; Thompson, Donna A

2016-09-01

(Meth)acrylates are important causes of contact allergy and allergic contact disease, such as dermatitis and stomatitis, with new and emerging sources resulting in changing clinical presentations. To identify the (meth)acrylates that most commonly cause allergic contact disease, highlight their usefulness for screening, and examine their relationship with occupational and clinical data. A retrospective review of results from patch tests performed between July 2002 and September 2015, in one tertiary Cutaneous Allergy Unit, was performed A series of 28 (meth)acrylates was applied to 475 patients. Results were positive in 52 cases, with occupational sources being identified in 24. Industrial exposures and acrylic nails were responsible for 13 and 10 cases, respectively, with wound dressings being implicated in 7. We found that four individual (meth)acrylates (2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, bisphenol A glycerolate dimethacrylate, and ethyl acrylate), if used as a screening tool, could have identified 47 (90.4%) of our positive cases. Our 13-year experience indicates a changing landscape of (meth)acrylate contact allergy and allergic contact disease, with an observed shift in exposures away from manufacturing and towards acrylic nail sources. Wound dressings are highlighted as emerging sources of sensitization. Larger studies are required to establish the sensitivity and specificity of the four (meth)acrylates proposed for potential screening. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Long-Term Stability of Oxide Nanowire Sensors via Heavily Doped Oxide Contact.

PubMed

Zeng, Hao; Takahashi, Tsunaki; Kanai, Masaki; Zhang, Guozhu; He, Yong; Nagashima, Kazuki; Yanagida, Takeshi

2017-12-22

Long-term stability of a chemical sensor is an essential quality for long-term collection of data related to exhaled breath, environmental air, and other sources in the Internet of things (IoT) era. Although an oxide nanowire sensor has shown great potential as a chemical sensor, the long-term stability of sensitivity has not been realized yet due to electrical degradation under harsh sensing conditions. Here, we report a rational concept to accomplish long-term electrical stability of metal oxide nanowire sensors via introduction of a heavily doped metal oxide contact layer. Antimony-doped SnO 2 (ATO) contacts on SnO 2 nanowires show much more stable and lower electrical contact resistance than conventional Ti contacts for high temperature (200 °C) conditions, which are required to operate chemical sensors. The stable and low contact resistance of ATO was confirmed for at least 1960 h under 200 °C in open air. This heavily doped oxide contact enables us to realize the long-term stability of SnO 2 nanowire sensors while maintaining the sensitivity for both NO 2 gas and light (photo) detections. The applicability of our method is confirmed for sensors on a flexible polyethylene naphthalate (PEN) substrate. Since the proposed fundamental concept can be applied to various oxide nanostructures, it will give a foundation for designing long-term stable oxide nanomaterial-based IoT sensors.

Children with atopic dermatitis may have unacknowledged contact allergies contributing to their skin symptoms.

PubMed

Simonsen, A B; Johansen, J D; Deleuran, M; Mortz, C G; Skov, L; Sommerlund, M

2018-03-01

Whether children with atopic dermatitis have an altered risk of contact allergy than children without atopic dermatitis is frequently debated and studies have been conflicting. Theoretically, the impaired skin barrier in atopic dermatitis (AD) facilitates the penetration of potential allergens and several authors have highlighted the risk of underestimating and overlooking contact allergy in children with atopic dermatitis. To determine the prevalence of contact allergy in Danish children with atopic dermatitis and explore the problem of unacknowledged allergies maintaining or aggravating the skin symptoms. In a cross-sectional study, 100 children and adolescents aged 5-17 years with a diagnosis of atopic dermatitis were patch tested with a paediatric series of 31 allergens. Thirty per cent of the children had at least one positive patch test reaction, and 17% had at least one contact allergy that was relevant to the current skin symptoms. The risk of contact allergy was significantly correlated to the severity of atopic dermatitis. Metals and components of topical skincare products were the most frequent sensitizers. Patch testing is relevant as a screening tool in the management of children with atopic dermatitis as they may have unacknowledged contact allergies contributing to or maintaining their skin symptoms. Children with atopic dermatitis seem to be at greater risk of sensitization to certain allergens including metals and components of skincare products. © 2017 European Academy of Dermatology and Venereology.

[Isothiazolinones as causal factors of contact allergy epidemics in the 20th and 21st centuries].

PubMed

Chomiczewska-Skóra, Dorota; Kręcisz, Beata; Kieć-Świerczyńska, Marta

2014-01-01

Chloromethylisothiazolinone (MCI) and methylisothiazolinone (MI) have been widely used as preservatives in cosmetics, household products and industrial products since the late 1970s. First cases of contact allergy to the MCI/MI combination were noted in 1980-1982 in Sweden. Then, a significant increase in the frequency of sensitization to these compounds was observed in many European centers. The increase has been stopped by the introduction of legislation on their maximum concentrations in consumer and industrial products in Europe and in some non-European countries. But approval of the use of MI alone without limits in industrial products (from 2000) and at a maximum concentration of 100 ppm in cosmetics (from 2005) resulted in an unprecedented increase in the number of individuals sensitized to this compound. Allergic contact dermatitis due to MI occurs in both adults and children. It is often manifested by severe symptoms, which may be also induced by airborne exposure. The most important sources of sensitization include cosmetic products and paints. To counteract the increasing problem of contact allergy epidemic to MI, the recommendations have been developed, suggesting the ban on the use of MI in "leave-on" cosmetics and maximum concentration of 15 ppm in "rinse-off" products. The recommendations are likely to be implemented in 2014.

[Assessment of the sensitizing potency of cosmetic ingredients and commodities. How will the ingredients of cosmetics and commodities be tested in Europe today and tomorrow?].

PubMed

Peiser, M; Platzek, T; Luch, A

2012-03-01

Cosmetics and certain commodities are applied or used by consumers directly on the skin. Creams may remain on the skin for longer periods, hair is dyed multiple times per year, nickel ions can be released from studs and piercings in areas of skin damage or migrate from toy materials into the skin of children. Accordingly, using or handling such products always entails a risk for developing a contact allergy. Moreover, daily usage and repeated contacts to certain cosmetics and commodities might lead to repeated elicitation of contact eczema in people already sensitized against allergenic ingredients. Unfortunately, contact allergy is not curable. For the assessment of the allergenic potential of chemicals, only testing based on animal experiments was available in the past. In 2003, the 7(th) amendment of the Cosmetics Directive 76/768/EWG laid down a ban on animal testing of cosmetic ingredients and from 2013 a general marketing ban of such products as well. Therefore, the development and validation of non-animal methods for assessing the toxicological endpoint sensitization/allergenic potency of chemicals is a major task for the years ahead and remains equally a challenge for industry and regulatory agencies.

Pramipexole-induced disruption of behavioral processes fundamental to intertemporal choice.

PubMed

Johnson, Patrick S; Stein, Jeffrey S; Smits, Rochelle R; Madden, Gregory J

2013-05-01

Evaluating the effects of presession drug administration on intertemporal choice in nonhumans is a useful approach for identifying compounds that promote impulsive behavior in clinical populations, such as those prescribed the dopamine agonist pramipexole (PPX). Based on the results of previous studies, it is unclear whether PPX increases rats' impulsive choice or attenuates aspects of stimulus control. The present study was designed to experimentally isolate behavioral processes fundamental to intertemporal choice and challenge them pharmacologically with PPX administration. In Experiment 1, the hypothesis that PPX increases impulsive choice as a result of enhanced sensitivity to reinforcer delays was tested and disconfirmed. That is, acute PPX diminished delay sensitivity in a manner consistent with disruption of stimulus control whereas repeated PPX had no effect on delay sensitivity. Experiments 2 and 3 elaborated upon this finding by examining the effects of repeated PPX on rats' discrimination of response-reinforcer contingencies and reinforcer amounts, respectively. Accuracy of both discriminations was reduced by PPX. Collectively these results provide no support for past studies that have suggested PPX increases impulsive choice. Instead, PPX impairs stimulus control over choice behavior. The behavioral approach adopted herein could be profitably integrated with genetic and other biobehavioral models to advance our understanding of impulsive behavior associated with drug administration. © Society for the Experimental Analysis of Behavior.

Endophthalmitis caused by Moraxella species.

PubMed

Berrocal, A M; Scott, I U; Miller, D; Flynn, H W

2001-11-01

To report the incidence, clinical presentation, antibiotic sensitivities, and treatment outcomes for endophthalmitis caused by Moraxella species. Consecutive interventional case series. Medical records were reviewed of all patients treated at Bascom Palmer Eye Institute between 1991 and 2000 for endophthalmitis caused by Moraxella species. Moraxella species were recovered from 9 patients (10 eyes), or 1.3% (10 of 757) of all culture-proven bacterial endophthalmitis cases; Moraxella catarrhalis was recovered from 7 eyes and Moraxella osloensis from 3. Endophthalmitis was delayed-onset (5 months to 10 years postoperatively) and bleb-associated in 9 eyes and trauma-related in 1. All isolates were sensitive to ceftazidime, ciprofloxacin, and the aminoglycosides, and they were resistant to vancomycin; resistance to ampicillin and trimethoprim/sulfa was 11%. Although presenting vision was hand motion or worse in 7 of 10 eyes, all but 3 regained baseline visual acuity (including two eyes in which the post-treatment course was complicated by retinal detachment and one eye with coexistent traumatic injuries). Endophthalmitis caused by Moraxella species is usually delayed-onset and bleb-associated. Although patients usually present with a profound decrease in vision, the organisms are sensitive to most antibiotics and, unlike most series of delayed-onset bleb-associated endophthalmitis, visual outcomes are generally good unless coexistent ocular morbidities exist.

Face distinctiveness and delayed testing: differential effects on performance and confidence.

PubMed

Metzger, Mitchell M

2006-04-01

The author investigated the effect of delayed testing on participants' memory for distinctive and typical faces. Participants viewed distinctive and typical faces and were then tested for recognition immediately or after a delay of 3, 6, or 12 weeks. Consistent with prior research, analysis of measure of sensitivity (d') showed that participants performed better on distinctive rather than typical faces, and memory performance declined with longer retention intervals between study and testing. Furthermore, the superior performance on distinctive faces had vanished by the 12-week test. Contrary to d' data, however, an analysis of confidence scores indicated that participants were still significantly more confident on trials depicting distinctive faces, even with a 12-week delay between study and recognition testing.

Allergic contact dermatitis caused by isobornyl acrylate in OmniPod, an innovative tubeless insulin pump.

PubMed

Raison-Peyron, Nadia; Mowitz, Martin; Bonardel, Nathalie; Aerts, Olivier; Bruze, Magnus

2018-04-10

The frequency of allergic contact dermatitis caused by (meth)acrylates is increasing worldwide, and isobornyl acrylate (IBOA) has been identified as a culprit sensitizer in FreeStyle Libre, a medical device used by diabetic patients. To report on 4 patients sensitized to IBOA contained in OmniPod, a new, tubeless insulin pump, and to describe the clinical and chemical analytical work-up. Four patients with eczematous skin eruptions after using OmniPod, including 2 with previous adverse skin reactions to FreeStyle Libre, were patch tested with a baseline series and additional (meth)acrylates, including IBOA in several concentrations and/or vehicles. Gas chromatography-mass spectrometry (GC-MS) was used to identify the presence of IBOA in OmniPod. All patients were shown to be sensitized to IBOA. GC-MS identified IBOA in OmniPod, with the highest concentrations being found in the unit itself and not in the adhesive patch. The OmniPod tubeless insulin pump is another source of IBOA, and its use may lead to primary sensitization to this acrylate, or may provoke elicitation of allergic contact dermatitis in previously sensitized patients. Our cases highlight the need to obtain satisfactory cooperation from pharmaceutical companies involved in the manufacture of these widely used medical devices. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Susceptibility of various areas of the nervous system of hens to TOCP-induced delayed neuropathy.

PubMed

Classen, W; Gretener, P; Rauch, M; Weber, E; Krinke, G J

1996-01-01

Sensitivity of in-life parameters, biochemical endpoints, and susceptibility of various areas of the chicken nervous system to delayed neuropathy induced by tri-orthocresyl phosphate (TOCP) was assessed. Groups of hens were exposed to a single oral dose of TOCP of 0, 50, 200 or 500 mg/kg and the animals observed for 21 days. Perfusion fixed, paraffin embedded tissue sections were stained with Bodian's silver and Luxol blue and semi-thin epoxy sections with toluidine blue. Sciatic and tibial nerves, lumbosacral, midthoracic, and upper cervical spinal cord, medulla oblongata and cerebellum were examined using a semiquantitative scoring system. In pair-dosed hens inhibition of brain and spinal cord neurotoxic esterase (NTE) and cholinesterase and of plasma and erythrocyte cholinesterases was determined 24 hr and 48 hr after administration. At all dose levels NTE in brain and spinal cord and plasma cholinesterase was inhibited markedly. Quantitative inhibition of NTE was seen also in absence of neuropathy. Ataxia and body weight loss occurred in high-dose animals only, while dose-related neuropathy was seen in the distal tibial nerve, medulla oblongata and cerebellum. Ataxia was correlated best with neuropathy in peripheral nerves while degeneration of nerve fibers in the cerebellum, seen best in mid-longitudinal sections, was the most sensitive histological indicator of TOCP-induced delayed neuropathy. The particular susceptibility of spinocerebellar neurons was recognized long ago, but often has been neglected in delayed neurotoxicity studies and respective guidelines. Optimal sensitivity of toxicity tests is a prerequisite for risk assessment, can be cost efficient, and nowadays should be a main interest of animal welfare in order to reduce animals' suffering. Based on these data, determination of NTE inhibition together with histopathological examination of longitudinal sections of distal tibial nerves, mid-longitudinal sections of rostral cerebellum and cross sections of upper cervical spinal cord represents an optimally sensitive and cost efficient test requirement.

The Development of Fine-Grained Sensitivity to Eye Contact after 6 Years of Age

ERIC Educational Resources Information Center

Vida, Mark D.; Maurer, Daphne

2012-01-01

Adults use eye contact as a cue to the mental and emotional states of others. Here, we examined developmental changes in the ability to discriminate between eye contact and averted gaze. Children (6-, 8-, 10-, and 14-year-olds) and adults (n=18/age) viewed photographs of a model fixating the center of a camera lens and a series of positions to the…

New generation methods for spur, helical, and spiral-bevel gears

NASA Technical Reports Server (NTRS)

Litvin, F. L.; Tsung, W.-J.; Coy, J. J.; Handschuh, R. F.; Tsay, C.-B. P.

1986-01-01

New methods for generating spur, helical, and spiral-bevel gears are proposed. These methods provide the gears with conjugate gear tooth surfaces, localized bearing contact, and reduced sensitivity to gear misalignment. Computer programs have been developed for simulating gear meshing and bearing contact.

New generation methods for spur, helical, and spiral-bevel gears

NASA Technical Reports Server (NTRS)

Litvin, F. L.; Tsung, W.-J.; Coy, J. J.; Handschuh, R. F.; Tsay, C.-B. P.

1987-01-01

New methods for generating spur, helical, and spiral-bevel gears are proposed. These methods provide the gears with conjugate gear tooth surfaces, localized bearing contact, and reduced sensitivity to gear misalignment. Computer programs have been developed for simulating gear meshing and bearing contact.

Contact-coupled impact of slender rods: analysis and experimental validation

PubMed Central

Tibbitts, Ira B.; Kakarla, Deepika; Siskey, Stephanie; Ochoa, Jorge A.; Ong, Kevin L.; Brannon, Rebecca M.

2013-01-01

To validate models of contact mechanics in low speed structural impact, slender rods were impacted in a drop tower, and measurements of the contact and vibration were compared to analytical and finite element (FE) models. The contact area was recorded using a novel thin-film transfer technique, and the contact duration was measured using electrical continuity. Strain gages recorded the vibratory strain in one rod, and a laser Doppler vibrometer measured speed. The experiment was modeled analytically on a one-dimensional spatial domain using a quasi-static Hertzian contact law and a system of delay differential equations. The three-dimensional FE model used hexahedral elements, a penalty contact algorithm, and explicit time integration. A small submodel taken from the initial global FE model economically refined the analysis in the small contact region. Measured contact areas were within 6% of both models’ predictions, peak speeds within 2%, cyclic strains within 12 με (RMS value), and contact durations within 2 μs. The global FE model and the measurements revealed small disturbances, not predicted by the analytical model, believed to be caused by interactions of the non-planar stress wavefront with the rod’s ends. The accuracy of the predictions for this simple test, as well as the versatility of the diagnostic tools, validates the theoretical and computational models, corroborates instrument calibration, and establishes confidence that the same methods may be used in experimental and computational study of contact mechanics during impact of more complicated structures. Recommendations are made for applying the methods to a particular biomechanical problem: the edge-loading of a loose prosthetic hip joint which can lead to premature wear and prosthesis failure. PMID:24729630

Defense responses regulated by jasmonate and delayed senescence caused by ethylene receptor mutation contribute to tolerance of petunia to Botrytis cinerea

USDA-ARS?s Scientific Manuscript database

The death of cells can be a programmed event that occurs when plants are attacked by pathogens. Botrytis cinerea (B. cinerea), a model necrotrophic pathogen, triggers the host cell death response because it produces toxins. A hypersensitive reaction (HR) occurs at the site of contact. In Arabidopsis...

Reflexes in cat ankle muscles after landing from falls.

PubMed Central

Prochazka, A; Schofield, P; Westerman, R A; Ziccone, S P

1977-01-01

1. Electrical activity and length of ankle muscles were recorded by telemetry during free fall and landing in cats. 2. After foot contact, there was a delay in onset of stretch of ankle extensors of between 8 and 11 ms. High-speed cinematography showed the delay to be associated with rapid initial dorsiflexion of the toes. 3. Electromyograms (e.m.g.) from lateral gastrocnemius increased in amplitude prior to landing. An early depression of lateral gastrocnemius e.m.g. commenced at 8 ms after foot contact, and was followed by a large peak of activity commencing some 8 ms after the first increase in lateral gastrocnemius length. 4. Local anaesthesia of the plantar cushion did not alter this pattern of response. 5. The early inhibition of lateral gastrocnemius was attributed to the action on lateral gastrocnemius motoneurones of non-cutaneous afferents responding to the initial toe dorsiflexion. Additional autogenetic inhibition may also have contributed. 6. The subsequent peak of e.m.g. was at a latenty consistent with a rapid stretch reflex, and occurred soon enough for the resulting active tension to contribute significantly to the extensor force during body deceleration. PMID:592210

Real-time energy-saving metro train rescheduling with primary delay identification

PubMed Central

Li, Keping; Schonfeld, Paul

2018-01-01

This paper aims to reschedule online metro trains in delay scenarios. A graph representation and a mixed integer programming model are proposed to formulate the optimization problem. The solution approach is a two-stage optimization method. In the first stage, based on a proposed train state graph and system analysis, the primary and flow-on delays are specifically analyzed and identified with a critical path algorithm. For the second stage a hybrid genetic algorithm is designed to optimize the schedule, with the delay identification results as input. Then, based on the infrastructure data of Beijing Subway Line 4 of China, case studies are presented to demonstrate the effectiveness and efficiency of the solution approach. The results show that the algorithm can quickly and accurately identify primary delays among different types of delays. The economic cost of energy consumption and total delay is considerably reduced (by more than 10% in each case). The computation time of the Hybrid-GA is low enough for rescheduling online. Sensitivity analyses further demonstrate that the proposed approach can be used as a decision-making support tool for operators. PMID:29474471

A comparison of between- and within-subjects imitation designs.

PubMed

Kressley, Regina A; Knopf, Monika

2006-12-01

Two experimental methods, which have dominated the study of declarative memory in preverbal children with imitation tasks, namely the deferred imitation and elicited imitation paradigm, differ in the amount of physical contact with test stimuli afforded infants prior to a test for long-term recall. The current study assessed effects of pre- and post-demonstration contact with test stimuli on deferred imitation of novel, single-step unrelated actions with multiple objects by 8(1/2)- and 10(1/2)-month-old infants (N=50). The rate of target action completion after a delay remained consistent at both ages across different conditions of prior contact with test stimuli. This study shows that a within-subjects baseline appraisal is valid within certain experimental parameters and offers a more economical alternative. The results show furthermore that different experimental designs utilized to assess deferred imitation are highly comparable for the first year despite differences in determining baseline.

Feasibility on Ultrasonic Velocity using Contact and Non-Contact Nondestructive Techniques for Carbon/Carbon Composites

NASA Astrophysics Data System (ADS)

Im, K. H.; Chang, M.; Hsu, D. K.; Song, S. J.; Cho, H.; Park, J. W.; Kweon, Y. S.; Sim, J. K.; Yang, I. Y.

2007-03-01

Advanced materials are to be required to have specific functions associated with extremely environments. One of them is carbon/carbon(C/C) composite material, which has obvious advantages over conventional materials. The C/Cs have become to be utilized as parts of aerospace applications and its low density, high thermal conductivity and excellent mechanical properties at elevated temperatures make it an ideal material for aircraft brake disks. Because of permeation of coupling medium such as water, it is desirable to perform contact-less nondestructive evaluation to assess material properties and part homogeneity. In this work, a C/C composite material was characterized with non-contact and contact ultrasonic methods using a scanner with automatic-data acquisition function. Also through transmission mode was performed because of the main limitation for air-coupled transducers, which is the acoustic impedance mismatch between most materials and air. Especially ultrasonic images and velocities for C/C composite disk brake were compared and found to be consistent to some degree with the non-contact and contact ultrasonic measurement methods. Low frequency through-transmission scans based on both amplitude of the ultrasonic pulse was used for mapping out the material property inhomogeneity. Measured results were compared with those obtained by the dry-coupling ultrasonic UT system and through transmission method in immersion. Finally, feasibility has been found to measure and compare ultrasonic velocities of C/C composites with using the contact/noncontact peak-delay measurement method based on the pulse overlap method.

Enhanced insulin sensitivity in prepubertal children with constitutional delay of growth and development.

PubMed

Wilson, Dyanne A; Hofman, Paul L; Miles, Harriet L; Sato, Tim A; Billett, Nathalie E; Robinson, Elizabeth M; Cutfield, Wayne S

2010-02-01

To test the hypothesis that prepubertal children with presumed constitutional delay of growth and development (CDGD) have enhanced insulin sensitivity and, therefore, insulin sensitivity is associated with later onset of puberty. Twenty-one prepubertal children with presumed CDGD and 23 prepubertal control children, underwent a frequently sampled intravenous glucose tolerance test to evaluate insulin sensitivity and other markers of insulin, glucose, and growth regulation. Children in the CDGD group were shorter and leaner than control subjects. Children with presumed CDGD were 40% more insulin sensitive (17.0 x 10(-4) min(-1)/[mU/L] versus 12.1 x 10(-4) min(-1)/[mU/L]; P = .0006) and had reduced acute insulin response, thus maintaining euglycemia (216 mU/L versus 330 mU/L; P = .02) compared with control subjects. In addition, the CDGD group had lower serum insulin-like growth factor binding protein 3 levels (3333 ng/mL versus 3775 ng/mL; P = .0004) and a trend toward lower serum insulin-like growth factor-II levels (794 ng/mL versus 911 ng/mL; P = .06). Prepubertal children with presumed CDGD have enhanced insulin sensitivity, supporting the hypothesis that insulin sensitivity is associated with timing of puberty. It may signify long-term biological advantages with lower risk of metabolic syndrome and malignancy. Copyright 2010 Mosby, Inc. All rights reserved.

Hopf bifurcation of an (n + 1) -neuron bidirectional associative memory neural network model with delays.

PubMed

Xiao, Min; Zheng, Wei Xing; Cao, Jinde

2013-01-01

Recent studies on Hopf bifurcations of neural networks with delays are confined to simplified neural network models consisting of only two, three, four, five, or six neurons. It is well known that neural networks are complex and large-scale nonlinear dynamical systems, so the dynamics of the delayed neural networks are very rich and complicated. Although discussing the dynamics of networks with a few neurons may help us to understand large-scale networks, there are inevitably some complicated problems that may be overlooked if simplified networks are carried over to large-scale networks. In this paper, a general delayed bidirectional associative memory neural network model with n + 1 neurons is considered. By analyzing the associated characteristic equation, the local stability of the trivial steady state is examined, and then the existence of the Hopf bifurcation at the trivial steady state is established. By applying the normal form theory and the center manifold reduction, explicit formulae are derived to determine the direction and stability of the bifurcating periodic solution. Furthermore, the paper highlights situations where the Hopf bifurcations are particularly critical, in the sense that the amplitude and the period of oscillations are very sensitive to errors due to tolerances in the implementation of neuron interconnections. It is shown that the sensitivity is crucially dependent on the delay and also significantly influenced by the feature of the number of neurons. Numerical simulations are carried out to illustrate the main results.

Missed or Delayed Cervical Spine or Spinal Cord Injuries Treated at a Tertiary Referral Hospital in Rwanda.

PubMed

Nkusi, Agabe Emmy; Muneza, Sévérien; Hakizimana, David; Nshuti, Steven; Munyemana, Paulin

2016-03-01

This study was aimed at 1) reporting cases of missed cervical spine injuries treated at a tertiary-level hospital, King Faisal Hospital, Rwanda (KFH-R), and 2) identifying the causes of delaying the diagnosis. We prospectively collected data from patients with a missed or delayed cervical spine and/or cord injury treated at King Faisal Hospital, Kigali for a 12-month period (January 2012 to December 2012). The total number of cervical spine injury patients treated at our center was retrieved from the hospital admission registry. Forty-two patients with cervical spine or spinal cord injuries were treated at KFH-R in 2012, and 4 of them had a missed or delayed diagnosis. Clinical and radiologic findings of all 4 patients are presented, and the reasons for delaying diagnosis are identified. This study found that the cervical spine injuries were missed in 9.5% of the cervical spine trauma patients and resulted in a longer hospital stay for all 4 patients and severe disability in 1 patient (25%). The reasons for missed diagnoses in this study were 1) lack of cervical spine radiographic evaluation, 2) inadequate cervical spine radiographs to show the level of injury, 3) poor sensitivity of cervical spine plain radiography, 4) poor physical examination, 5) the presence of a distracting injury, and 6) poor sensitivity of radiographs and computed tomography scans for soft tissue injuries. Copyright © 2016 Elsevier Inc. All rights reserved.

Newborn Auditory Brainstem Evoked Responses (ABRs): Longitudinal Correlates in the First Year.

ERIC Educational Resources Information Center

Murray, Ann D.

1988-01-01

Aimed to determine to what degree newborns' auditory brainstem evoked responses (ABRs) predict delayed or impaired development during the first year. When 93 infants' ABRs were evaluated at three, six, and nine months, newborn ABR was moderately sensitive for detecting hearing impairment and more sensitive than other indicators in detecting…