Detection Of Initiation Research Articles

Projected effectiveness of HIV detection during early infection and rapid ART initiation among MSM and transgender women in Peru: A modeling study.

BackgroundThe Sabes study, a treatment as prevention intervention in Peru, tested the hypothesis that initiating antiretroviral therapy (ART) early in HIV infection when viral load is high, would markedly reduce onward HIV transmission among high-risk men who have sex with men (MSM) and transgender women (TW). We investigated the potential population-level benefits of detection of HIV early after acquisition and rapid initiation of ART.MethodsWe designed a transmission dynamic model to simulate the HIV epidemic among MSM and TW in Peru, calibrated to data on HIV prevalence and ART coverage from 2004 to 2011. We assessed the impact of an intervention starting in 2018 in which up to 50% of the new infections were diagnosed within three months of acquisition and initiated on ART within 1 month of diagnosis. We estimated the impact of the intervention over 20 years using the cumulative prevented fraction of new HIV infections compared to scenarios without intervention.FindingsOur model suggests that only 19% of the infected MSM and TW are virally suppressed in 2018 and 35%–40% of the new HIV infections are transmitted from contacts with acutely-infected partners. An intervention reaching 10% of all acutely infected MSM and TW is projected to prevent 13.3% [Uncertainty interval: 11.9%–14.3%] of the new infections over 20 years and reduce HIV incidence in 2038 by 24%. Reaching 50% of all acutely infected MSM and TW will increase the prevalence of viral suppression in 2038 to 59% and prevent 41% of expected infections over 20 years. Reaching 50% of the high-risk MSM and TW in acute phase would reduce HIV incidence in 2038 by 60% and prevent 36% of new infections between 2018 and 2038.ConclusionsEarly detection of HIV infections and rapid initiation of ART among MSM is desirable as it would increase the effectiveness of the HIV prevention program in Peru. Targeting high-risk MSM and TW will be highly efficient.

An In-line, High Sensitivity, Non-contact Sensor for the Detection of Initiation of Sticking

Purpose In this paper, the development and testing of a laser sensor to detect initiation of sticking are discussed.

Grasping the weight cut-off for anorexia nervosa in children and adolescents.

The Diagnostic and Statistical Manual of Mental Disorders 5 suggests the 5th age-adjusted body mass index (BMI) percentile as the numeric cut-off for anorexia nervosa (AN) in children and adolescents. We aimed to investigate the degree to which the 5th age-adjusted percentile as the numeric cut-off for AN in youths reflects the clinical population of patients accepted for treatment. From a specialized eating disorder clinic, 305 patients with AN below 18 years of age were grouped according to age-adjusted BMI percentiles [below the 5th (low), above the 10th (high), and between the 5th and the 10th (medium)]. The distribution of eating disorder diagnoses and severity measured by the Eating Disorder Examination was compared. Full-syndrome anorexia nervosa (F.50.0) was found in 182 (59.5%) patients and atypical anorexia nervosa (F.50.1) in 123 patients (40.5%). The number of patients in the low, medium, and high BMI percentile groups was 189 (62.0%), 34 (11.1%), and 82 (26.9%), respectively. Patients in the low BMI group differed from patients in the medium BMI group by a lower frequency of vomiting. The high BMI group presented with more weight and shape concern than the lower BMI group. Age was not a confounder of these associations. We question the applicability of the 5th BMI percentile as a substantiated cut-off for the weight criterion in anorexia nervosa in youths and argue that the cut-off should not be ascribed great clinical importance as this may hinder early detection of illness and initiation of treatment.

2082. Using a Commercially Available Assay Measuring Cytomegalovirus (CMV)-Specific CD4+ and CD8+ T-Cell Immunity by Intracellular Cytokine Staining to Predict Clinically Significant CMV Events

BackgroundCytomegalovirus (CMV) infection is a common opportunistic infection associated with significant morbidity, mortality, and risk of allograft loss. Early detection of viremia and initiation of treatment prior to disease progression is paramount. Alternatively, in the absence of treatment, many patients also control CMV infection, including low-level viremia, without progressing to disease. Thus, many treatment decisions (e.g., viremia thresholds to initiate treatment) are not currently well-defined. Given the excessive toxicities and costs of antiviral therapy, there is growing interest in assays that measure CMV-specific T-cell immunity (TCI), which may predict protection against infection. The Viracor® CMV T-cell Immunity Panel (CMV-TCIP) uses flow cytometry and intracellular cytokine staining (ICS) to measure % of CMV-specific CD4+ and CD8+ T-cells. Other currently available TCI commercial assays measure only aggregate (CD4+ and CD8+) or CD8+ immune responses only.MethodsWe included patients who had CMV-TCIP results at Rhode Island Hospital (January 2016–February 2018) and who subsequently had at least one additional assessment for CMV viremia. CMV events were defined as rising viremia prompting initiation of treatment and were captured after the most recent CMV-TCIP result. We built CMV-protection relative-operating curves (ROC) for % of CD4+ and CD8+ CMV-specific T-cells.ResultsWe analyzed 17 samples from 13 patients: 10 were SOT (eight kidney, two heart) recipients (seven CMV R+, three D+/R−); two had hematologic malignancies; one other was immunosuppressed (prednisone, infliximab) for autoimmune colitis. Four additional samples were excluded because of CD4+ or CD8+ ICS background positivity. The CMV-protection ROC AUC was significant for % of CMV-specific CD4+ but not CD8+ T-cells (Figure 1). At a cut-off of 0.26% CMV-specific CD4+ T-cells, PPV was 90% (95% CI 71–100%), and NPV was 86% (95% CI 60–100%). In 14 of 17 cases (82%), the CMV-TCIP result was useful in guiding management.ConclusionIn this small, single-center, heterogeneous series, the % of CMV-specific CD4+ T-cells measured by ICS was predictive of protection against CMV. The CMV-TCIP can be a useful, cost-effective test, and merits further validation in larger prospective studies. Figure 1.Disclosures D. Farmakiotis, Viracor: Consultant and Invited speaker, Consulting fee.

Circulating BRAF V600E Cell-Free DNA as a Biomarker in the Management of Anaplastic Thyroid Carcinoma.

Anaplastic thyroid cancer (ATC) is a deadly form of thyroid cancer. BRAF V600E is the only actionable mutation for which there is a Food and Drug Administration-approved drug combination. Rapid detection of BRAF V600E and initiation of therapy is critical. We explored the ability of droplet digital polymerase chain reaction (ddPCR) to identify this mutation in circulating cell-free DNA (cfDNA) in plasma. The ddPCR assay was evaluated for its sensitivity, specificity for detection of BRAF V600E cfDNA, and concordance with tumor tissue. The assay also was used to evaluate its potential role as a biomarker of response. Forty-four patients with ATC who were tested for the BRAF mutation by tumor tissue DNA sequencing or immunohistochemistry were included. Sixteen BRAF V600E-positive patients had treatment samples to evaluate cfDNA levels as a biomarker of response in correlation with restaging scans. Concordance of ddPCR with tumor tissue was 93%, with a sensitivity of 85% and specificity of 100%. Area under the curve by Wilcoxon rank sum test was 0.9 (95% CI, 0.80 to 0.99; P < .001). As a biomarker of response to treatment, 94% of ddPCR samples were concordant with tumor shrinkage in restaging scans, and 47% were concordant with tumor growth (Fisher's exact test P = .0061). In addition, cfDNA levels by ddPCR were predictive of treatment response in 71% of samples. cfDNA detection by ddPCR is highly sensitive, specific, and concordant with mutation status on ATC tumors. ddPCR also can be used for monitoring cfDNA levels in conjunction with imaging scans in patients with ATC.

Detection and treatment initiation for depression and alcohol use disorders: facility-based cross-sectional studies in five low-income and middle-income country districts

ObjectivesTo estimate the proportion of adult primary care outpatients who are clinically detected and initiate treatment for depression and alcohol use disorder (AUD) in low-income and middle-income country (LMIC) settings.DesignFive...

Emergent Wave Conversion as a Precursor to Shear Crack Initiation

AbstractGeophysical assessments of subsurface instability rely on a link between physical failure mechanisms and a geophysical measurement. Here a laboratory study demonstrates the emergence of a converted phase at the damage onset in limestone prior to failure from shear crack formation. Shear (S) to compressional (P) wave conversions arise from the presence of an array of disconnected microcracks and occur prior to the crack initiation detection from surface displacement measurements. The converted waves increase in amplitude with shear crack propagation until crack coalescence. The inception of the S to P wave converted phase supports the use of elastic wave conversions as an active diagnostic tool to detect the initiation and propagation of shear cracks.

Effect of Multiwalled Carbon Nanotubes on Sensing Crack Initiation and Ultimate Strength of Cement Nanocomposites

Sensing crack in multiwalled carbon nanotube (MWCNT)-reinforced cement under compression stress was investigated to aid in the temporal detection of crack initiation. Cement-based nanocomposite specimens were prepared with fixed proportions (e.g., water/cement ratio and sand/cement ratio) and varying concentrations of MWCNTs (0.01%, 0.02%, 0.1% and 0.2% by weight of cement). Microstructure was analyzed by means of a scanning electron microscope to show crack bridging and EDX spectroscopy to confirm the existence of MWCNTs in cement paste. Crack monitoring was presented through the variation of the temporal slope of electrical resistance during compression stress of nanocomposite samples. It is shown that temporal slope variation can be used as an index for crack warning owing to its well-defined patterns with distinct peaks that correlate with crack initiations and propagation. A significant increase in ultimate compressive strength with MWCNT concentration more than 0.1 wt% with respect to cement was observed.

Interference of Therapeutic Monoclonal Antibodies With Routine Serum Protein Electrophoresis and Immunofixation in Patients With Myeloma: Frequency and Duration of Detection of Daratumumab and Elotuzumab.

We investigated the frequency and pattern of detection of therapeutic monoclonal antibodies (t-mAbs) daratumumab and elotuzumab by routine serum protein electrophoresis (SPE) and immunofixation (IF) in treated patients with myeloma. Detection of t-mAb was assessed in 22 patients by retrospective review of SPE/IF ordered prior to, during, and after 26 individual courses of therapy. t-mAb was distinguishable from M-protein in 16 of 26 courses, with daratumumab detected in nine of nine and elotuzumab in six of seven patients. t-mAb was detected on first follow-up SPE/IF in 12 patients, with earliest detection 7 days after therapy initiation and latest detection 70 days after therapy. t-mAb persisted throughout induction therapy in most patients, with loss of detection during maintenance daratumumab. When distinguishable from M-protein, t-mAbs are detectable in 93% of treated patients as soon as 7 days after the initial dose and are consistently observed throughout induction therapy, warranting increased monitoring and careful interpretation of SPE/IF.

The nondestructive evaluation of the GFRP composite plate with an elliptical hole under fatigue loading conditions

Abstract The accurate assessment of the fatigue strength for structures made of composite materials is difficult because of the great number of possible failure forms. The Structural Health Monitoring (SHM) systems are developed and applied in engineering structures for permanent monitoring the state of the constructions. In this paper the Lamb wave propagation method and the infrared thermography were applied to observe the fatigue damage evolution in the multilayered composite plate with an elliptical hole in the middle. The active pitch-catch measurement technique was introduced based on the surface mounted piezoelectric transducers. The localization of the piezoelectric actuator and sensors responsible for excitation and detection of the elastic wave was chosen based on the progressive failure analysis applied in finite element method. The multipoint measuring system was responsible for analysis of the elastic wave propagation phenomenon during the fatigue tests. The sequential measurement of the elastic wave parameters allow one to observe the state of the structure. The different parameters describing the wave propagation phenomenon like amplitude and time of flight was considered. The infrared thermography make possible of detection of the damage initiation and permanent monitoring of the structure. The measurement of the temperature distribution is straightforward and doesn’t need complicated algorithms and software. Application of the coupled approach to the damage detection (piezoelectric transducers in SHM system with the permanent surface temperature monitoring) allow one to build cost effective system for detection of the damage initiation and for monitoring failure form evolution.

Damage characteristics analysis of GFRP-Balsa sandwich beams under Four-point fatigue bending

Four-point bending static and fatigue experiments were performed on composite sandwich beams with glass fiber reinforced polymer (GFRP) face sheets and Balsa wood cores. Specimens with various span-to-depth ratios were prepared using a vacuum-assisted resin transfer molding process. The results showed that the sandwich beams under both static and fatigue tests failed due to core shear and debonding. The S–N curves of sandwich beams were determined using an exponential empirical model. The study showed that to sustain at least one million cycles, the service load should be limited to 60% of the ultimate load. The deflection evolution of the sandwich beams were found to occur in three stages, namely, transient fall, stable evolution, and rapid failure. Furthermore, a fatigue damage model closely related to the possible detection of damage initiation and progression was proposed. The model was proved to be appropriate for describing the fatigue response of GFRP-Balsa sandwich beams.

Evaluation of molecular tests in diagnosis of osteoarticular tuberculosis

Osteoarticular tuberculosis is a relatively uncommon type of extrapulmonary tuberculosis. It is an important cause of mortality and morbidity and accounts for approximately 10-15% of all extrapulmonary forms of tuberculosis. The diagnosis is difficult and hence often late. The disability resulting from osteoarticular tuberculosis is directly related to the time of detection of disease and initiation of treatment. A prospective study of 36 patients suspected with osteoarticular tuberculosis was done from August 2010 to December 2012 was done at St. stephens hospital Delhi. For the purpose of this study, a diagnosis of osteoarticular TB was based on a combination of suggestive clinical features, in conjunction with typical radiological findings associated with osteoarticular TB. The specimens were subjected to ZN staining, Real Time PCR, Bac-T alert culture & Accuprobe. The sensitivity of real time PCR was 100%, specificity was 58.8%, positive predictive value was 73%, negative predictive value was 100%, efficiency was 80.5% considering culture as gold standard. As shown by the study, each diagnostic test including Real time PCR has its own disadvantages and shortcomings and does not provide 100% accuracy in diagnosing osteoarticular tuberculosis, therefore, strong clinical suspicion and correlation along with radiological and laboratory evidence is a must in establishing a diagnosis.

Design Strategy of the Sabes Study: Diagnosis and Treatment of Early HIV Infection Among Men Who Have Sex With Men and Transgender Women in Lima, Peru, 2013-2017.

The Sabes Study evaluated a treatment-as-prevention intervention among cisgender men who have sex with men and transgender women in Lima, Peru-populations disproportionately affected by the human immunodeficiency virus (HIV) epidemic. The intervention was designed to prevent onward transmission of HIV by identifying HIV-negative high-risk individuals, testing them monthly for the presence of HIV, and then rapidly treating those who became HIV-positive. The main outcome of interest was the development of a model predicting the population-level impact of early detection of HIV infection and immediate initiation of antiretroviral therapy in this population. From July 2013 to September 2015, a total of 3,337 subjects were screened for HIV; 2,685 (80.5%) were negative, and 2,109 began monthly testing. We identified 256 individuals shortly after HIV acquisition, 216 of whom were enrolled in the treatment phase of the study. All participants were followed for 48 weeks (follow-up ended in 2017) and were then referred to the Peruvian Ministry of Health to continue receiving free HIV care and treatment. Initial findings from this intervention demonstrate that it is possible to recruit high-risk individuals, screen them for HIV, continue to test those who are initially HIV-negative in order to identify incident cases shortly after acquisition, and then rapidly link them to health care.

Assessment of intraspecies variability in fungal growth initiation of Aspergillus flavus and aflatoxin B1 production under static and changing temperature levels using different initial conidial inoculum levels

Intraspecies variability in fungal growth and mycotoxin production has important implications for food safety. Using the Bioscreen C we have examined spectrophotometrically intraspecies variability of A. flavus using 10 isolates under different environments, including temperature shifts, in terms of growth and aflatoxin B1 (AFB1) production. Five high and five low AFB1 producers were examined. The study was conducted at 5 isothermal conditions (from 15 to 37 °C) and 4 dynamic scenarios (between 15 and 30 °C). The experiments were carried out in a semisolid YES medium at 0.92 aw and two inoculum levels, 102 and 103 spores/mL. The Time to Detection (TTD) of growth initiation was determined and modelled as a function of temperature through a polynomial equation and the model was used to predict TTD under temperature upshifts conditions using a novel approach. The results obtained in this study have shown that a model can be developed to describe the effect of temperature upshifts on the TTD for all the studied isolates and inoculum levels. Isolate variability increased as the growth conditions became more stressful and with a lower inoculum level. Inoculum level affected the intraspecies variability but not the repeatability of the experiments. In dynamic conditions, isolate responses depended both on the temperature shift and, predominantly, the final temperature level. AFB1 production was highly variable among the isolates and greatly depended on temperature (optimum temperature at 30–35 °C) and inoculum levels, with often higher production with lower inoculum. This suggests that, from an ecological point of view, the potential isolate variability and interaction with dynamic conditions should be taken into account in developing strategies to control growth and predicting mycotoxin risks by mycotoxigenic fungi.

A review of non-destructive techniques used for mechanical damage assessment in polymer composites

Polymer composite materials are being increasingly used in primary load-bearing structures in several advanced industrial fields such as aerospace vessels, railway wagons and mega-scaled wind turbines where detection of subcritical damage initiation can significantly reduce safety issues and maintenance costs. It is therefore crucial to inspect these composite structures in order to assess their structural health and to ensure their integrity. Non-destructive testing techniques (NDT) are used for this purpose, making it possible to monitor mechanical damage of composite materials under in situ or ex situ service conditions. This paper reviews the capabilities of the most common NDT techniques used to inspect the integrity of composite materials. Each technique has a detection potential and cannot allow a full diagnosis of the mechanical damage state of the material. Thus, depending on the occurring damage mechanism and the conditions of use, one technique will be preferred over another, or several techniques should be combined to improve the diagnosis of the damage state of the structures.

Acoustic Emission from Microcrack Initiation in Polymer Matrix Composites in Short Beam Shear Test

Acoustic emission (AE) was applied for detection of microcrack initiation in carbon fiber reinforced polymer composites subjected to shear stresses. Experimental materials were prepared from polyester bonded unidirectional (1D) non-crimp fabric and 2D plain-weave carbon fiber fabrics, using the resin transfer moulding technology. Control of epoxy resin/carbon textile proportions enabled variation of fiber volume content from small (34/35% for 2D/1D), through medium (51%) to high (68%). Rectangular samples (45 times 4 times 2 mm) were cut from 1D plates along [0] and across [90] fibers. Similar size samples from 2D plates were cut along warp/weft axes as well as in two orthogonal bias directions. Selected side surfaces were polished for microscopic (SEM) observations. Short-beam-strength tests were performed in 3-point bending (l/h=4), with two AE sensors attached for damage monitoring, which allowed to interrupt loading sequence before final failure. The acoustic emission historic index was the most effective AE parameter in damage initiation control. Microcracks developing on polished composite side-surfaces were observed under the SEM and direct microscopic evidence confirmed fiber debonding to be the principal mechanism of crack initiation in these materials and testing conditions before any further damage.

Temperature dependent crack initiation of 42CrMo4 steel at high loading rates

Dynamic crack initiation with crack tip loading rates K˙ of approximately 2 ‧ 106 MPa√ms− in high-strength 42CrMo4 steel was investigated. To this end, a recently developed split Hopkinson pressure bar with four-point bending was utilized. V-notched and precracked Charpy specimens were tested. The tests were performed at temperatures of –40 °C and 20 °C. The loading of the specimen was determined by analyzing the strain in the incident and transmission bars. Furthermore, strain gauges at the specimen’s surface were applied to measure the crack tip loading. High-speed photography complemented the analysis of the specimens loading and the detection of the crack initiation. Fracture surface analysis by means of scanning electron microscopy enabled the measurement of the fracture surface topography and, consequently, stretch zone height and width. Hence, the macroscopically measured dynamic crack initiation toughness was correlated with the toughness at microscopic scale. It was observed that the resistance against dynamic crack initiation decreased with decreasing temperature. Microscopically, a decrease in toughness was analogously observed. Non-metallic inclusions resulted in crack path deflection with localized shear zones. After a small stable crack extension, cleavage fracture was observed.

Status of Noncommunicable Disease Screening in an Urban Resettlement Colony in Delhi, India: A Descriptive Cross-Sectional Study

Background Noncommunicable diseases (NCDs) are responsible for more than two-third cases of premature mortality (30–69 years) in India. Screening for NCDs is the most effective means for detection of undiagnosed NCD cases and early treatment initiation that lowers morbidity and mortality due to these diseases. The objective of the present study was to assess the NCD screening status in an urban resettlement colony of Delhi. Materials and Methods A community-based cross-sectional study was conducted among residents of the area. Patients with preexisting hypertension and diabetes and aged below 30 years were excluded. The patients were further screened for hypertension by taking three separate readings using an aneroid sphygmomanometer. The Indian Diabetes Risk Score (IDRS) was calculated to evaluate diabetes risk. Results A total of 110 men and 103 women (N = 213) met the inclusion criteria. The mean (±standard deviation) age of the patients was 40 (±9.3) years. A history of previous screening for hypertension and diabetes was reported by 73 (34.2%) and 40 (35.4%) patients, respectively. A medium or high-risk of having diabetes mellitus as per the IDRS score was present in most (88.4%) patients. On current screening, nine (8.2%) men and nine (8.7%) women were identified as undiagnosed hypertension cases. Only four (3.8%) women had undergone a clinical breast exam, and just nine (8.7%) women ever had a Pap smear examination. Conclusion The present study shows that the current strategy of opportunistic screening for NCDs has been unable to reach large segments of vulnerable and at risk populations.

NEUROPSYCHOLOGY AND THE NEUROPHYSIOLOGY OF PERCEPTUAL MICROGENESIS

Perception is one of the psychological operations that can be analyzed from the point of view of microgenetic theory. Our study tests the basic premise of microgenesis theory – the existence of recurrent stages of visual information processing. The event related potentials in two variants of a cued GO/NOGO task (contrasting images of Animals and Plants in the first variant, and contrasting images of Angry and Happy faces in the second variant) were studied during the first 300 ms following stimulus presentation. The independent component analysis was applied to a large collection of ERPs. The functional independent components associated with visual category discrimination, comparison to working memory, action initiation and conflict detection were separated. Information processing in the ventral visual stream (the temporal independent components) occurs at two sequential stages with positive/negative fluctuations of the cortical potential as indexes of the stages. The first stage represents the comparison of the pure physical features of the visual input with the memory trace. The second stage represents the comparison of more sophisticated semantic/emotional features with the working memory. The two stages are the results of interplay between bottom-up and top-down projections in the visual ventral stream.

Damage accumulation and crack initiation detection based on the evolution of surface roughness parameters

Cyclic strain localization generates sharp surface slip markings in the form of depressions and elevations on the surface of materials. The process gives rise to the formation of persistent slip bands and results in immanent changes that manifest themselves in the form of surface roughening. The heights and depths of these extrusions and intrusions grow during cyclic loading up to a critical value leading to crack initiation. In this study, we investigate the evolution of the surface roughness parameters starting from pristine specimens and ending in final fracture in fully-reversed cyclic bending tests. Results are presented for both low-and high-cycle fatigue that covers a wide range of surface finish. Two types of contacting (via a stylus) and no-contacting (optical) profilometers were used in this investigation. The most sensitive and useful surface roughness parameter for the assessment of fatigue growth in low-and high-cycle fatigue is identified, and it is shown that results can be utilized to detect the onset of fatigue crack nucleation. For this purpose, a surface roughness criterion for detecting crack initiation at different applied loads is introduced.