High Frequency Testing Research Articles

Profile of Persons Recently Infected with HIV-1 in Belgium: New Insights to Tailor Prevention Efforts.

Despite wide availability of prevention and treatment services, including the ongoing roll-out of pre-exposure prophylaxis (PrEP), the HIV epidemic is not under control in Belgium. Hence, there is a recognized need to improve case finding and early diagnosis to curb the further spread of HIV more effectively. The objective of the present study was to improve insight into the profiles of persons recently infected with HIV-1 and on their prevention trajectory. Between May 2018 and December 2022, we selected persons diagnosed in Belgium within three months of the presumed infection date. We then analyzed information collected using a questionnaire covering topics on HIV testing, sexually transmitted infections (STIs), PrEP use, sexual behavior, partner notification and substance use. The data obtained were analyzed alongside information derived from phylogenetic cluster analysis of the viral source of infection. A total of 93 persons with a recent HIV-1 infection completed the questionnaire, the majority (74%) being MSM, 14% were heterosexual women and 12% were heterosexual men. Nearly one-third of participants engaged in sexual activity with an average of 2 to 5 casual partners around the presumed time of infection. A significant percentage reported frequent substance use during sexual activity (65%), being previously diagnosed with STI (65%) and using condoms infrequently (44%). 63% reported a testing frequency of at least one HIV test per year before being diagnosed and 46% notified their previous sex partner(s) after being diagnosed. Over 20% of respondents (including 11 MSM, 4 heterosexual men and 5 heterosexual women) reported exclusive sexual activity with their steady partner. Eight participants (9%, all MSM, 75% born outside of Belgium) reported PrEP use in the past. No significant differences in behavioral characteristics were found between persons who were part of a local transmission cluster (48%) and persons that were not part of a cluster (47%). The study results revealed that the majority of persons diagnosed early with HIV-1 infection in Belgium exhibited characteristics corresponding to a high-at-risk population and were aware of this risk, as evidenced by a high testing frequency. However, partner notification rates were low and use and awareness of PrEP limited. A notable group of persons not corresponding to the high-risk profiles was also identified. This information may help to expose missed opportunities for prevention and contribute to enhancing the implementation of future prevention measures.

To Use or Not to Use a Self-monitoring of Blood Glucose System? Real-world Flash Glucose Monitoring Patterns Using a Cluster Analysis of the FGM-Japan Study.

Objective This study investigated self-monitoring of blood glucose (SMBG) adherence and flash glucose monitoring patterns using a cluster analysis in Japanese type 1 diabetes (T1D) patients with intermittently scanned continuous glucose monitoring (isCGM). Methods We measured SMBG adherence and performed a data-driven cluster analysis using a hierarchical clustering in T1D patients from Japan using the FreeStyle Libre system. Clusters were based on three variables (testing glucose frequency and referred Libre data for hyperglycemia or hypoglycemia). Patients We enrolled 209 participants. Inclusion criteria were patients with T1D, duration of isCGM use ≥3 months, age ≥20 years old, and regular attendance at the collaborating center. Results The rate of good adherence to SMBG recommended by a doctor was 85.0%. We identified three clusters: cluster 1 (low SMBG test frequency but high reference to Libre data, 17.7%), cluster 2 (high SMBG test frequency but low reference to Libre data, 34.0%), and cluster 3 (high SMBG test frequency and high reference to Libra data, 48.3%). Compared with other clusters, individuals in cluster 1 were younger, those in cluster 2 had a shorter Libre duration, and individuals in cluster 3 had lower time-in-range, higher severe diabetic distress, and high intake of snacks and sweetened beverages. There were no marked differences in the incidence of diabetic complications and rate of wearing the Libre sensor among the clusters. Conclusions We stratified the patients into three subgroups with varied clinical characteristics and CGM metrics. This new substratification might help tailor diabetes management of patients with T1D using isCGM.

A novel measurement method for ash deposition based on coplanar capacitance principle: Theoretical, numerical and experimental studies

Monitoring for the fouling and slagging is critical to ensure the stable operation of gasification system. This paper proposes a novel measurement method for the ash deposition based on coplanar capacitance principle. A theoretical analysis of electrostatic field is conducted to obtain the correlation between the coplanar capacitance value and the deposition thickness. A finite element simulation is carried out to discuss the electric field characteristics of ash depositing on the coplanar capacitor. It shows that the capacitance value initially increases and tends to be constant with the increase of deposition thickness. The lower distance between positive and negative electrodes is favorable to the capacitance value (signal strength) but unfavorable to the maximum measurable thickness. Furthermore, a cold state experiment is conducted to verify the correctnesses of the theoretical and numerical models, and a hot state experiment is carried out to study the capacitance characteristics of sensor in the high temperature range of 700 °C–1200 °C. Results show that the permittivity of the material is lower under the higher test frequency, which leads to the lower capacitance value of sensor. The complex impedance curve of ash is conformed to IBLC dielectric model, this explains that the sensor capacitance increases with the test temperature increasing caused by the increase of permittivity due to the enlargement of ash grain. The change of Si/Al content has little effect on the dielectric properties of ash, however, the higher Fe2O3 content or the lower CaO content results into the lower ash fusion point, larger grain size, and thence higher permittivity and sensor capacitance. The maximum measurable thicknesses of the sensors in the cold state and hot state are 11.2 mm and 10.0 mm, respectively, which are independent with the test frequency, test temperature, and ash component.

Improved resonance method for fatigue test of full-scale wind turbine blades

To further reduce the power of exciter in the common fatigue testing methods and increase the testing frequency to decrease the fatigue testing time, this paper proposes an improved fatigue testing method—Tug Fatigue Testing system (TFTs). The advantages of this new fatigue testing method are low power and high testing frequency of its exciter due to no exciter with moving masses attached to the blade. In TFTs, exciters mounted on the ground or fixed bracket can be used to excite the blade in the uniaxial or biaxial fatigue test. In this paper, the mechanical model of TFTs is established to compare the motor power required by exciters in TFTs and the inertial exciters and the shear load on the blades in both ways. Furthermore, a test of a 56.5 m blade will be performed to verify the feasibility of the new method. In addition, the bending moment distribution of an 80 m blade excited by TFTs was measured and compared with the bending moment distribution of the same blade excited by inertial resonance excitation to evaluate its excitation effect. The test results prove that this improved method needs lower power of exciter, produces smaller shear loads, and provides a higher test frequency in the flap-wise test direction than common inertial resonance excitation. Biaxial fatigue tests can also be conducted by this new method.

Integration of Sequencing and Epidemiologic Data for Surveillance of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infections in a Tertiary-Care Hospital.

BackgroundThe ongoing COVID-19 pandemic significantly burdens hospitals and other healthcare facilities. Therefore, understanding the entry and transmission of SARS-CoV-2 is critical for effective prevention and preparedness measures. We performed surveillance and analysis of testing and transmission of SARS-CoV-2 infections in a tertiary-care hospital in Germany during the second and third pandemic waves in fall/winter 2020.MethodsBetween calendar weeks 41/2020 and 1/2021 40% of all positive patient and staff samples (284 total) were subjected to full-length viral genome sequencing. Clusters were defined based on similar genotypes indicating common sources of infection. We integrated phylogenetic, spatial, and temporal metadata to detect nosocomial infections and outbreaks, uncover transmission chains, and evaluate containment measures’ effectiveness.ResultsEpidemiologic data and contact tracing readily recognize most healthcare-associated patient infections. However, sequencing data reveal that temporally preceding index cases and transmission routes can be missed using epidemiologic methods, resulting in delayed interventions and serially linked outbreaks being counted as independent events. While hospital-associated transmissions were significantly elevated at a moderate rate of community transmission during the second wave, systematic testing and high vaccination rates among staff have led to a substantial decrease in healthcare-associated infections at the end of the second/beginning of the third wave despite high community transmissions.ConclusionsWhile epidemiologic analysis is critical for immediate containment of healthcare-associated SARS-CoV-2 outbreaks, integration of genomic surveillance revealed weaknesses in identifying staff contacts. Our study underscores the importance of high testing frequency and genomic surveillance to detect, contain and prevent SARS-CoV-2-associated infections in healthcare settings.

Automated Urinal-Based Specific Gravity Measurement Device for Real-Time Hydration Monitoring in Male Athletes.

Acute and chronic hydration status is important for athlete safety and performance and is frequently measured by sports scientists and performance staff in team environments via urinalysis. However, the time required for urine collection, staff testing, and reporting often delays immediate reporting and personalized nutrition insight in situations of acute hydration management before training or competition. Furthermore, the burdensome urine collection and testing process often renders chronic hydration monitoring sporadic or non-existent in real-world settings. An automated urinalysis device (InFlow) was developed to measure specific gravity, an index of hydration status, in real-time during urination. The device was strongly correlated to optical refractometry with a mean absolute error of 0.0029 (±0.0021). Our results show this device provides a novel and useful approach for real-time hydration status via urinalysis for male athletes in team environments with high testing frequency demands.

A new LFSR based high-frequency test method for RSFQ circuit

Rapid single flux quantum (RSFQ) circuits have the advantages of high speed and low power consumption. The typical frequency of the RSFQ circuits is tens of GHz. Therefore, it is necessary to reliably test the high-frequency performance of RSFQ circuits simply and effectively. This paper proposes a new on-chip high-frequency testing method, which uses pseudo-random sequences generated by linear feedback shift register (LFSR) as the test vectors, and the output shift registers (SRs) to store the last piece of high-frequency testing result and read out it at low-frequency. Unlike the traditional high-frequency demonstration method of using the Input/Output SRs, our testing system can automatically generate a large number of test vectors to test the circuit at high frequency at low cost, making the whole high-frequency demonstration more reliable and convincing. On the other hand, this method is also a feasible and straightforward on-chip high-frequency test method for various RSFQ circuits. This work verified the proposed method, and the highest test frequency can reach 54 GHz while the circuit shows good operating margins.

A hybrid stochastic model and its Bayesian identification for infectious disease screening in a university campus with application to massive COVID-19 screening at the University of Liège

Amid the COVID-19 pandemic, universities are implementing various prevention and mitigation measures. Identifying and isolating infectious individuals by using screening testing is one such a measure that can contribute to reducing spread. Here, we propose a hybrid stochastic model for infectious disease transmission in a university campus with screening testing and its surrounding community. Based on a compartmental modeling strategy, this hybrid stochastic model represents the evolution of the infectious disease and its transmission using continuous-time stochastic dynamics, and it represents the screening testing as discrete stochastic events. We also develop, in a Bayesian framework, the identification of parameters of this hybrid stochastic model, including transmission rates. These parameters were identified from the screening test data for the university population and observed incidence counts for the surrounding community. We implement the exploration of the Bayesian posterior using a machine-learning simulation-based inference approach. The proposed methodology was applied in a retrospective modeling study of a massive COVID-19 screening conducted at the University of Liège in Fall 2020. The emphasis of the paper is on the development of the hybrid stochastic model to assess the impact of screening testing as a measure to reduce spread. The hybrid stochastic model allows various factors to be represented and examined, such as interplay with the surrounding community, variability of the transmission dynamics, the rate of participation in the screening testing, the test sensitivity, the test frequency, the diagnosis delay, and compliance with isolation. The application in the retrospective modeling study suggests that a high rate of participation and a high test frequency are important factors to reduce spread.

Consideration of the Heating of High-Performance Concretes during Cyclic Tests in the Evaluation of Results

Material-efficient, highly load-bearing members made of high-performance compressive concretes are often exposed to cyclical loads because of their slender construction, which can be relevant to the design. When investigating the fatigue behaviour of high-performance concretes in pressure swell tests, however, the specimen temperature rises strongly owing to the elevated loading rate at frequencies higher than 3 Hz. This leads to a negative influence on the achieved number of load cycles compared to tests carried out at slow speeds and calculated values, for example, according to fib Model Code 2010. This phenomenon, which was already observed, must be considered when generating design formulae or Wöhler lines for component design, as the test conditions with high constant load frequencies as well as sample storage in a climate chamber at constant conditions are prerequisites that cannot be expected in real material applications. Therefore, laboratory testing influences must be eliminated in order to avoid underestimating the material. Instead of adjusting the test conditions to prevent or control temperature development, as was the case in previous approaches, this article shows how the temperature effects can be corrected when analysing the results, considering both the applied stress and the maximum temperature reached. For this purpose, a calculation method was developed that was validated on the basis of a large number of fatigue tests. Thus, in the future, the application of one temperature sensor to the test specimen can effectively advance the extraction of values for Wöhler curves, even with high test frequencies.

Improved calibration technique for two-probe setup to enhance its in-circuit impedance measurement accuracy

The in-circuit impedance is a key parameter to evaluate the health and operation of many electrical systems. The two-probe setup (TPS) based on the inductive coupling approach is preferred for in-circuit impedance measurement because it does not require physical electrical contact with the energized system under test. However, the existing calibration technique for the TPS degrades its measurement accuracy at relatively high test frequencies. To enhance the measurement accuracy of the TPS, this paper proposes an improved calibration technique. It considers the frequency-dependent effects of the selected calibration components so that the TPS can maintain good measurement accuracy even at relatively high test frequencies. Using an actual TPS as a test case, experimental results show that the TPS based on the proposed calibration technique maintains good measurement accuracy up to 10 MHz, whereas the same TPS based on the existing calibration technique exhibits significant measurement errors when approaching 10 MHz.

Detection of porcine reproductive and respiratory syndrome virus (PRRS) genome fragments and anti-- bodies in chewing ropes allow -monitoring of PRRS in pig farms

Saliva samples from chewing ropes are a reliable diagnostic of porcine reproductive and respiratory syndrome virus (PRRSV) infections. The aim of this study was to test whether saliva samples taken with saliva swabs (cotton swabs and GenoTube Livestock) or with chewing ropes are suitable for monitoring PRRSV in unsuspicious farms, this means to detect a prevalence of 20% infected animals with a 95% probability. Saliva samples were collected from 12-16 pens in five pig farms by using a chewing rope for collective samples and by individual saliva swaps from five randomly selected animals per pen. A total of 291 animals from 58 pens in four study farms and 60 animals from 12 pens in one control farm were collected. The samples were taken from all age categories. According to the current monitoring system the analysis of five individual serum samples from the same pens served as the reference method for the relative sensitivity of the saliva samples. Serum and chewing rope samples were tested by ELISA for antibodies. Two different systems were used for the serum samples. Chewing ropes, saliva swabs (GenoTube Livestock) and serum samples were examined for virus genomes using a nested reverse-transcriptase PCR and a commercial real-time reverse-transcriptase PCR kit. Cohen's Kappa was used as a measure of agreement. PRRSV antibodies were detected in the chewing ropes of 44 pens and in the serum samples of only 34 pens. Viral RNA was found in 13 (chewing ropes), respectively 16 pens (serum samples). Saliva swabs (GenoTube Livestock) showed a lower relative sensitivity of 20.00% compared to serum samples. The agreement of the two serum analysis was very good for the ELISAs (κ = 0,911), and moderate for the PCR (κ = 0,706). The comparison of the chewing rope method with the analysis of the serum samples advocates this method as a suitable supplementary monitoring tool in PRRSV unsuspicious pig farms. Easy handling and lower examination costs of the chewing rope method allow higher testing frequency and would therefore improve the monitoring system. However, they are not an alternative to serum samples. Sampling with saliva swabs is unsuitable.

Occupational Noise Exposure and Longitudinal Hearing Changes in Post-9/11 US Military Personnel During an Initial Period of Military Service.

Auditory impairments, particularly those resulting from hazardous occupational noise exposures, are pressing concerns for the US Departments of Defense (DoD) and Veterans Affairs (VA). However, to date, no studies have estimated the rate of hearing threshold change that occurs during service or how changes may vary by military occupation. Hearing threshold changes during military service have historically been reported as the proportion of Service members demonstrating a significant threshold shift. This approach does not capture the rate of the hearing threshold change or the specific audiometric frequencies impacted. Determining the rate of hearing threshold change, and factors that affect the rate of change, is important to elucidate the impact of military service on hearing and to guide prevention strategies and subsequent hearing health care. Our primary objective was to estimate the annual rate of hearing threshold change during military service as a consequence of military occupational noise exposure ranking. We linked audiometric data, collected from military personnel as part of a DoD hearing conservation program, to data describing demographic and military-service characteristics obtained from individuals enrolled in the Noise Outcomes In Service members Epidemiology Study. The analytic cohort included Veterans who enlisted in military service after September 2001 (n = 246). We examined the longitudinal association between military occupations categorized as having a low, moderate, or high noise exposure ranking and pure-tone hearing thresholds (500 to 6000 Hz) using a hierarchical linear model. The average annual rate of hearing threshold change and their 95% confidence intervals were estimated by service branch, military occupational noise exposure ranking, and audiometric test frequency. On average, hearing threshold change ranged between -0.5 and 1.1 dB/year and changes over time varied by service branch, audiometric test frequency, and military occupation noise ranking. Generally, higher test frequencies (3000 to 6000 Hz) and military occupations with moderate or high noise exposure rankings had the greatest average annual rates of hearing threshold change; however, no dose-response relationship was observed. Among Marine Corps personnel, those exposed to occupations with high noise rankings demonstrated the greatest average annual rate of change (1.1 dB/year at 6000 Hz). Army personnel exposed to occupations with moderate noise rankings demonstrated the greatest average annual rate of change (0.6 dB/year at 6000 Hz). This study (1) demonstrates the unique use of DoD hearing conservation program data, (2) is the first analysis of hearing threshold changes over time using such data, and (3) adds to the limited literature on longitudinal changes in hearing. The difference in hearing threshold changes across military branches is likely indicative of their varying noise exposures, hearing protection device use and enforcement, and surveillance practices. Results suggest Marine Corps and Army personnel are at risk for hearing threshold changes and that, among Army personnel, this is most pronounced among those exposed to moderate levels of occupational noise exposure. Estimates of the rate of hearing threshold change by frequency and factors that impact hearing are useful to inform the DoD's efforts to protect the hearing of their Service members and to the Veterans Affairs's efforts to identify and rehabilitate those most likely to experience hearing threshold change.

Simulation-Based What-If Analysis for Controlling the Spread of COVID-19 in Universities

A simulation model is developed to analyze the spread of COVID-19 in universities. The model can be used to conduct what-if analysis and to estimate infection cases and the probability of death for students and faculty/staff under different policies. For proof-of-concept, the model is simulated for a hypothetical university of 25,000 students and 3,000 faculty/staff in a US college town. In this case, students arrive on campus in September and the semester is planned to last for a 90-day period. In base run, absent major policies other than reactive testing at 500 tests per day (sensitivity=.8, specificity=.998), limited quarantine of 170 beds, and R0=3, the disease quickly spreads and the probability of having at least 1, 2, and 5 deaths by the middle of the semester reaches .94, .78, and .16 for students, and ~1, ~1, and ~1 for faculty/staff. Simulation results show that there is no silver bullet to avoid an outbreak and, instead, a combination of policies should be carefully implemented. The effectiveness of proactive testing highly depends on testing capacity (to maintain high test frequency) and, inversely, on the delay between symptom onset and test results. Contact tracing and quarantine only when combined with other policies such as rapid, frequent testing and mask use enforcement are effective. To decrease death likelihood, universities should ask all staff/faculty of over 60 years old, and a large fraction of 30-60 years old to work remotely. Simulation results suggest these alternatives: 1) (almost) full remote operation from the beginning, 2) remote operation for high-risk individuals (all over 60s and most of 30-60s) in addition to frequent rapid tests, contact tracing with high capacity for quarantine, enforcing mask use, and social distancing. Results show that the system is highly vulnerable, and considering implementation challenges, many universities are likely to close and switch to remote classes to avoid catastrophic outcomes. A simulation platform for what-if analysis is offered so marginal effectiveness of different policies, and different decision making thresholds for closure can be tested for universities of varying populations. The model in Vensim is available. A web app is provided at https://forio.com/app/navidg/covid-19-v2/ and an instructional video is available at https://youtu.be/PrYarrpqa4Y for further analysis.

Impedansa sistema uzemljenja - opseg frekvencijske linearnosti

The measurement of grounding system impedance of in-service power facilities is a very complex issue since the power system frequency interference and harmonic frequencies may adversely affect the measurement. Recently, to overcome this problem the Frequency Shift Method (FSM) has been proposed. FSM requires that two of three test frequencies must be above power system frequency (in our case 50 Hz). However, due to the nonlinear dependence of the grounding system impedance versus frequency, the choice of test frequencies is not arbitrary. In this paper, this issue is experimentally examined based on the analysis of grounding system impedance linearity range. For this purpose, the grounding system impedance, for a sample of 16 substations (HV and MV), is examined. We find that the highest test frequency should be ≤80 Hz.

A reinforcement learning model to inform optimal decision paths for HIV elimination.

The ‘Ending the HIV Epidemic (EHE)’ national plan aims to reduce annual HIV incidence in the United States from 38,000 in 2015 to 9,300 by 2025 and 3,300 by 2030. Diagnosis and treatment are two most effective interventions, and thus, identifying corresponding optimal combinations of testing and retention-in-care rates would help inform implementation of relevant programs. Considering the dynamic and stochastic complexity of the disease and the time dynamics of decision-making, solving for optimal combinations using commonly used methods of parametric optimization or exhaustive evaluation of pre-selected options are infeasible. Reinforcement learning (RL), an artificial intelligence method, is ideal; however, training RL algorithms and ensuring convergence to optimality are computationally challenging for large-scale stochastic problems. We evaluate its feasibility in the context of the EHE goal. We trained an RL algorithm to identify a ‘sequence’ of combinations of HIV-testing and retention-in-care rates at 5-year intervals over 2015–2070 that optimally leads towards HIV elimination. We defined optimality as a sequence that maximizes quality-adjusted-life-years lived and minimizes HIV-testing and care-and-treatment costs. We show that solving for testing and retention-in-care rates through appropriate reformulation using proxy decision-metrics overcomes the computational challenges of RL. We used a stochastic agent-based simulation to train the RL algorithm. As there is variability in support-programs needed to address barriers to care-access, we evaluated the sensitivity of optimal decisions to three cost-functions. The model suggests to scale-up retention-in-care programs to achieve and maintain high annual retention-rates while initiating with a high testing-frequency but relaxing it over a 10-year period as incidence decreases. Results were mainly robust to the uncertainty in costs. However, testing and retention-in-care alone did not achieve the 2030 EHE targets, suggesting the need for additional interventions. The results from the model demonstrated convergence. RL is suitable for evaluating phased public health decisions for infectious disease control.

Pesticide selectivity to the parasitoid Trichogramma pretiosum: A pattern 10-year database and its implications for Integrated Pest Management

Trichogramma pretiosum is one of the main egg parasitoids used in the control of lepidopteran pests in Brazil. This natural enemy can be negatively affected by the use of insecticides, herbicides, and fungicides. The present work used a systematic review and meta-analysis to group information from multiple studies on the selectivity of pesticides (279 commercial products) in rice, corn, soybean, apple and peach crops for immature stages (egg-larva, pre-pupa, and pupa) and adult parasitoids. The selected studies used the International Organization for Biological and Integrated Control (IOBC) methodology with the same adaptations for T. pretiosum. The meta-analysis found that corn crops had the highest frequency of tests (2 0 7). The most frequently tested active ingredients (a.i.) were glyphosate, glyphosate isopropylamine salt, and sulfur at frequencies of 41, 32 and 24 tests, respectively. The pesticides registered for rice crops showed the greatest sublethal effects on T. pretiosum, with an approximately 47% reduction in parasitism (RP) or emergence (RE). The adult stage of the parasitoid showed greater sensitivity to the tested pesticides (65% RP), in comparison to the immature stages. In general, insecticides showed superior toxicity for all development stages of T. pretiosum, compared to herbicides and fungicides, regardless of the recommended dosage for the crop. The present study aggregates information related to selectivity for the four life stages of T. pretiosum, contributing significantly to the integration of biological control and chemical control in rice, corn, soybean, apple and peach crops in Brazil.

Perceived HIV stigma and HIV testing among men and women in rural Uganda: a population-based study

Stigma is a formidable social structural barrier to HIV testing, and yet the effect of stigma on HIV testing is rarely examined at the community level. We aimed to examine the geospatial relationships of perceived HIV stigma and HIV testing among men and women living in rural Uganda. Women and men (aged ≥18 years or emancipated minor) residing in rural areas of Uganda who self-identified as HIV negative completed interviews that included measures of HIV testing history and how participants perceived HIV stigma. We used geospatial cluster analyses to identify areas of higher perceived stigma and lower perceived stigma and the geographical dispersion of these areas. We used Poisson regression models stratified by gender to test individual-level and community-level perceived stigma in relation to frequency of HIV testing in the previous 2 years. Between Nov 25, 2015, and May 26, 2017, we interviewed 9740 participants (4359 [45%] men and 5381 [55%] women]), among whom 940 (9%) had never been tested for HIV, and among those who had been tested, 1131 (12%) had not been tested in the previous 2 years. Men (3134 [72%] of 4359) were less likely to have been tested in the past 2 years than women (4535 [84%] of 5381) were (p<0·001). We used Poisson regression models, reporting B coefficients, to test study hypotheses regarding the effects of individual-level and community-level stigma on HIV testing frequency counts. Multilevel modelling showed that women showed significant individual-level (B=-0·173, p<0·001) and community-level (B=-0·223, p<0·001) associations between lower stigma predicting higher rates of HIV testing. For men, lower individual-level perceived stigma was also associated with higher testing frequency (B=-0·030, p=0·018), whereas higher community-level perceived stigma was associated with higher testing frequency (B=0·077, p=0·008). Our results suggest that perceived HIV stigma at the community level exerts a differential influence on testing for women and men. HIV testing campaigns that are targeted to men and women in rural Uganda will require gender tailoring to fit local contexts. US National Institute of Mental Health.

Ethnic and socio-economic disparities in prostate cancer screening: lessons from New Zealand.

To investigate the presence of ethnic and socio-economic disparities in prostate cancer (PCa) screening and identify its impact on cancer outcomes. From January 2008 to December 2017, all men in the Northern region of New Zealand who had a prostate-specific antigen (PSA) test performed in the community were identified from the electronic laboratory reports database. Asymptomatic men, with no known diagnosis of PCa, were included. Variables collected were age, ethnicity, social deprivation, medical therapy, PSA test information and cancer data. Disparities were investigated by comparing the frequency of PSA testing, proportions of men screened, and rates of cancer detection, between Māori (indigenous) and non-Māori ethnic groups. The study cohort included 248 491 men, who each received approximately 3.45 PSA tests over the 10-year study period. Māori men were less likely to be tested compared to non-Māori men (25.4% vs 46.1% of the total aged-matched region population; P < 0.001). Moreover, they received less frequent PSA testing irrespective of their deprivation status (mean difference of 0.97 PSA tests per person; P < 0.001). The higher testing frequency in non-Māori men was associated with increased PCa diagnosis rates. Nevertheless, cancers detected in Māori men were 73% more likely to be of high grade (Gleason 8 or above), compared to those in non-Māori men. There were significant ethnic disparities in PCa screening rates in the Northern region of New Zealand. Māori men, regardless of other demographic factors, were disproportionately affected. The difference in the rates of screening by ethnicity had influenced the incidence and clinical significance of the diagnosed cancers.

Enhancing thermal conductivity of the insulating layer of high-frequency copper clad laminates via incorporating surface modified spherical hBN fillers

The rapid development of modern information technology needs highly thermal-conductive with high-frequency copper clad laminates (HFCCLs) as a key point. In this study, ShBN (spherical hexagonal boron nitride) and ShBN/KH550 (surface modified by KH550) were used as fillers to enhance the thermal conductivity for the insulating layer of HFCCLs. Due to the merits of not only the rotational symmetry for effective thermal networks, but also a compatibility with the polymer matrix, the ShBN/KH550 filled with HFCCLs (SK-CCLs) could reach a high value of 1.18 W m−1K−1 when the content of the filler was 63 wt%. On the other hand, the incorporation of ShBN and ShBN/KH550 fillers had led to the decrease the dielectric losses with a low dielectric permittivity even at a high testing frequency of 5 GHz. In addition, the peel strength and flexural strength of the HFCCLs were not significantly reduced with the addition of either ShBN or ShBN-KH550 fillers, showing the same downward trend. This study presents a new direction to promote the conductive insulating layer for HFCCLs to meet the high requirement of upcoming 5G or 6G era.

A cohort study comparing rate of repeat testing for sexually transmitted and blood-borne infections between clients of an internet-based testing programme and of sexually transmitted infection clinics in Vancouver, Canada

ObjectivesInternet-based sexually transmitted and blood-borne infection (STBBI) testing services reduce testing barriers through bypassing face-to-face clinical encounters, potentially enabling clients at ongoing sexual risk to test more frequently. To our...