A simple technique for high resolution time domain phase noise measurement

A new time domain phase comparator is described. The device uses a novel technique to allow time domain phase measurements to be made with period and time interval counters without the use of offset reference oscillators. The device uses a single reference oscillator and allows measurements with a phase resolution greater than the noise floor of the reference. Data is presented showing a phase resolution of 0.02ps at 5 MHz with a crystal reference. The device has application in measuring the phase stability of systems where approximate phase quadrature can be maintained

016— Quality of College Students’ Close Peer Relationships

This study compares the quality of different types of college students’ relationships: same-sex (SS) friendships, other-sex (OS) friendships, and romantic relationships. Previous research by Hand and Furman (2009) indicated that adolescents perceived their OS friendships as less supportive than both their SS friendships and romantic relationships. Adolescents also perceived their OS friendships as having less conflict than their romantic relationships. The current study attempts to replicate these findings with college students, who tend to have more time and opportunity to develop close OS friendships. In addition, we examine the power dynamic in these relationships, as well as several factors of each type of relationship, including length of the current relationship and previous experience with each type of relationship

Arrow-mounted ballistic system for measuring performance of arrows equipped with hunting broadheads

Measuring an arrow's ballistic performance such as arrow velocity on impact, total time of flight and arrow shaft oscillation is challenging because of the dynamic nature of arrow flight. This challenge becomes increasingly difficult as the distance of the shot increases. It is also of great interest to bowhunters to understand the ballistic performance of arrows that include hunting broadheads. A miniaturized, sensory data acquisition system, located in the arrow tip and engineered to withstand the high accelerations experienced at launch and impact, enables the precise measurement of arrow ballistics in flight. By continuously recording arrow drag in flight, the system enables measurement of the ballistic performance of an arrow as it travels downrange. The authors have also built an adapter that is connected to the housing of the sensing system to allow for comparative ballistic tests to be performed on hunting broadheads. Here, we present results obtained using the sensing system to perform initial testing on two commercially available broadheads at shot distances of approximately 45 m

High Frequency of Cytomegalovirus-Specific Cytotoxic T-Effector Cells in HLA-A*0201-Positive Subjects during Multiple Viral Coinfections

How the cellular immune response copes with diverse antigenic competition is poorly understood. Responses of virus-specific cytotoxic T lymphocytes (CTL) were examined longitudinally in an individual coinfected with human immunodeficiency virus type 1 (HIV-1), Epstein-Barr virus (EBV), and cytomegalovirus (CMV). CTL responses to all 3 viruses were quantified by limiting dilution analysis and staining with HLA-A*0201 tetrameric complexes folded with HIV-1, EBV, and CMV peptides. A predominance of CMV-pp65-speciflc CTL was found, with a much lower frequency of CTL to HIV-1 Gag and Pol and to EBV-BMLF1 and LMP2. The high frequency of CMV-speciflc CTL, compared with HIV-1- and EBV-specific CTL, was confirmed in an additional 16 HLA-A*0201-positive virus-coinfected subjects. Therefore, the human immune system can mount CTL responses to multiple viral antigens simultaneously, albeit with different strength

VINYL COATING OF GRAPHITE PLATES FOR ULTRASONIC INSPECTION

A process has been developed for application of a thin, adherent vinyi plastic coating to graphite plates to prevent absorption of coupling fluids'' used in ultrasonic inspection. The plates are preheated and dipped mechanically in a fluid plastisol, and the resulting coating is fused in an infra-red heater. No significant attenuation of ultrasonic impulse results from presence of the coating. After inspection, the vinyl sheath may be easily stripped from the plate. (auth

Molecularly Self-Assembled Nucleic Acid Nanoparticles for Targeted In Vivo siRNA Delivery

Nanoparticles are employed for delivering therapeutics into cells1,2. However, size, shape, surface chemistry and the presentation of targeting ligands on the surface of nanoparticles can affect circulation half-life and biodistribution, cell specific internalization, excretion, toxicity, and efficacy3-7. A variety of materials have been explored for delivering small interfering RNAs (siRNAs) - a therapeutic agent that suppresses the expression of targeted genes8,9. However, conventional delivery nanoparticles such as liposomes and polymeric systems are heterogeneous in size, composition and surface chemistry, and this can lead to suboptimal performance, lack of tissue specificity and potential toxicity10-12. Here, we show that self-assembled DNA tetrahedral nanoparticles with a well-defined size can deliver siRNAs into cells and silence target genes in tumours. Monodisperse nanoparticles are prepared through the self-assembly of complementary DNA strands. Because the DNA strands are easily programmable, the size of the nanoparticles and the spatial orientation and density of cancer targeting ligands (such as peptides and folate) on the nanoparticle surface can be precisely controlled. We show that at least three folate molecules per nanoparticle is required for optimal delivery of the siRNAs into cells and, gene silencing occurs only when the ligands are in the appropriate spatial orientation. In vivo, these nanoparticles showed a longer blood circulation time (t1/2 ∼ 24.2 min) than the parent siRNA (t1/2 ∼ 6 min)

Diabetes Mellitus and Mortality after Acute Coronary Syndrome as a First or Recurrent Cardiovascular Event

Diabetes Mellitus (DM) is associated with adverse cardiovascular prognosis. However, the risk associated with DM may vary between individuals according to their overall cardiovascular risk burden. Therefore, we aimed to determine whether DM is associated with poor outcome in patients presenting with Acute Coronary Syndrome (ACS) according to the index episode being a first or recurrent cardiovascular event.We conducted a retrospective analysis of a prospective cohort study involving 2499 consecutively admitted patients with confirmed ACS in 11 UK hospitals during 2003. Usual care was provided for all participants. Demographic factors, co-morbidity and treatment (during admission and at discharge) factors were recorded. The primary outcome was all cause mortality (median 2 year follow up), compared for cohorts with and without DM according to their prior cardiovascular disease (CVD) disease status. Adjusted analyses were performed with Cox proportional hazards regression analysis. Within the entire cohort, DM was associated with an unadjusted 45% increase in mortality. However, in patients free of a history of CVD, mortality of those with and without DM was similar (18.8% and 19.7% respectively; p = 0.74). In the group with CVD, mortality of patients with DM was significantly higher than those without DM (46.7% and 33.2% respectively; p<0.001). The age and sex adjusted interaction between DM and CVD in predicting mortality was highly significant (p = 0.002) and persisted after accounting for comorbidities and treatment factors (p = 0.006). Of patients free of CVD, DM was associated with smaller elevation of Troponin I (p<0.001). However in patients with pre-existing CVD Troponin I was similar (p = 0.992).DM is only associated with worse outcome after ACS in patients with a pre-existing history of CVD. Differences in the severity of myocyte necrosis may account for this. Further investigation is required, though our findings suggest that aggressive primary prevention of CVD in patients with DM may have beneficially modified their first presentation with (and mortality after) ACS

Burnout syndrome in Cypriot physiotherapists: a national survey

Background. Burnout in the healthcare workers is formally defined as a state of physical, emotional and mental exhaustion caused by long-term involvement in situations that are emotionally demanding. Methods. Using a random stratified sampling method and taking into account geographical location, specialty and type of employment, 172 physiotherapists working both in the private and public sectors completed an anonymous questionnaire that included several aspects related to burnout; the MBI scale, questions related to occupational stress, and questions pertaining to self image. Results. Almost half (46%) of the 172 participants believed that their job is stressful. Approximately 57% of the physiotherapists who worked in the public sector and 40% of those who worked in the private sector (p = 0.038) reported that their job is stressful. In total, 21.1% of participants met Maslach's criteria for burnout. The point prevalence of burnout was as follows: (1) 13.8% of those who worked in the public sector and 25.5% of those in the private sector (2) 22.2% of males and 20% of females (3) 21.6% who were married, 18% who were single and 33.3% who were separated. Gender was found to be associated with the level of personal accomplishment (chi-squared test; p = 0.049), as 17.8% of men compared with 24.3% of women reported high personal accomplishment. The number of years of working as a physiotherapist correlated negatively (r = -0.229, p = 0.004) with the total depersonalization score. Regression analysis showed that the perception that the job is stressful (p < 0.001) and the low salary (p = 0.016) were significant predictors of high emotional exhaustion scores, while age group (p = 0.027) predicted high scores of depersonalization and the employment sector (p = 0.050) as well as the low salary predicted high personal accomplishment scores. Conclusions. Burnout levels in physiotherapists in Cyprus ranged from low to moderate

Association of Circulating Tumor DNA Testing Before Tissue Diagnosis With Time to Treatment Among Patients With Suspected Advanced Lung Cancer: The ACCELERATE Nonrandomized Clinical Trial.

IMPORTANCE Liquid biopsy has emerged as a complement to tumor tissue profiling for advanced non-small cell lung cancer (NSCLC). The optimal way to integrate liquid biopsy into the diagnostic algorithm for patients with newly diagnosed advanced NSCLC remains unclear. OBJECTIVE To evaluate the use of circulating tumor DNA (ctDNA) genotyping before tissue diagnosis among patients with suspected advanced NSCLC and its association with time to treatment. DESIGN, SETTING, AND PARTICIPANTS This single-group nonrandomized clinical trial was conducted among 150 patients at the Princess Margaret Cancer Centre-University Health Network (Toronto, Ontario, Canada) between July 1, 2021, and November 30, 2022. Patients referred for investigation and diagnosis of lung cancer were eligible if they had radiologic evidence of advanced lung cancer prior to a tissue diagnosis. INTERVENTIONS Patients underwent plasma ctDNA testing with a next-generation sequencing (NGS) assay before lung cancer diagnosis. Diagnostic biopsy and tissue NGS were performed per standard of care. MAIN OUTCOME AND MEASURES The primary end point was time from referral to treatment initiation among patients with advanced nonsquamous NSCLC using ctDNA testing before diagnosis (ACCELERATE [Accelerating Lung Cancer Diagnosis Through Liquid Biopsy] cohort). This cohort was compared with a reference cohort using standard tissue genotyping after tissue diagnosis. RESULTS Of the 150 patients (median age at diagnosis, 68 years [range, 33-91 years]; 80 men [53%]) enrolled, 90 (60%) had advanced nonsquamous NSCLC. The median time to treatment was 39 days (IQR, 27-52 days) for the ACCELERATE cohort vs 62 days (IQR, 44-82 days) for the reference cohort (P < .001). Among the ACCELERATE cohort, the median turnaround time from sample collection to genotyping results was 7 days (IQR, 6-9 days) for plasma and 23 days (IQR, 18-28 days) for tissue NGS (P < .001). Of the 90 patients with advanced nonsquamous NSCLC, 21 (23%) started targeted therapy before tissue NGS results were available, and 11 (12%) had actionable alterations identified only through plasma testing. CONCLUSIONS AND RELEVANCE This nonrandomized clinical trial found that the use of plasma ctDNA genotyping before tissue diagnosis among patients with suspected advanced NSCLC was associated with accelerated time to treatment compared with a reference cohort undergoing standard tissue testing. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT04863924

Seroprevalence of Toxoplasma gondii infection in arthritis patients in eastern China

Background: There is accumulating evidence for an increased susceptibility to infection in patients with arthritis. We sought to understand the epidemiology of Toxoplasma gondii infection in arthritis patients in eastern China, given the paucity of data on the magnitude of T. gondii infection in these patients. Methods: Seroprevalence of T. gondii infection was assessed by enzyme-linked immunosorbent assay using a crude antigen of the parasite in 820 arthritic patients, and an equal number of healthy controls, from Qingdao and Weihai cities, eastern China. Sociodemographic, clinical and lifestyle information on the study participants were also obtained. Results: The prevalence of anti-T. gondii IgG was significantly higher in arthritic patients (18.8%) compared with 12% in healthy controls (P < 0.001). Twelve patients with arthritis had anti-T. gondii IgM antibodies comparable with 10 control patients (1.5% vs 1.2%). Demographic factors did not significantly influence these seroprevalence frequencies. The highest T. gondii infection seropositivity rate was detected in patients with rheumatoid arthritis (24.8%), followed by reactive arthritis (23.8%), osteoarthritis (19%), infectious arthritis (18.4%) and gouty arthritis (14.8%). Seroprevalence rates of rheumatoid arthritis and reactive arthritis were significantly higher when compared with controls (P < 0.001 and P = 0.002, respectively). A significant association was detected between T. gondii infection and cats being present in the home in arthritic patients (odds ratio [OR], 1.68; 95% confidence interval [CI]: 1.24 – 2.28; P = 0.001). Conclusions: These findings are consistent with and extend previous results, providing further evidence to support a link between contact with cats and an increased risk of T. gondii infection. Our study is also the first to confirm an association between T. gondii infection and arthritis patients in China. Implications for better prevention and control of T. gondii infection in arthritis patients are discussed. Trial registration: This is an epidemiological survey, therefore trial registration was not required