Diagnostic Test

The Mu2e Experiment at Fermilab will search for the conversion of a muon to an electron in the field of an atomic nucleus with unprecedented sensitivity. The experiment requires a beam consisting of proton bunches approximately 200ns FW long, separated by 1.7 microseconds, with no out-of-time protons at the 10⁻¹⁰ fractional level. The verification of this level of extinction is very challenging. The proposed technique uses a special purpose spectrometer which will observe particles scattered from the production target of the experiment. The acceptance will be limited such that there will be no saturation effects from the in-time beam. The precise level and profile of the out-of-time beam can then be built up statistically, by integrating over many bunches.

Chain reactions are characterized by initiation, propagation and termination, are stochastic at microscopic scales and underlie vital chemical (e.g. combustion engines), nuclear and biotechnological (e.g. polymerase chain reaction) applications.1–5 At macroscopic scales, chain reactions are deterministic and limited to applications for entertainment and art such as falling domino and Rube Goldberg machines. Appositely, microfluidic lab-on-a-chip (also called a micro total analysis system),6,7 which were envisioned pursuant to microelectronic integrated circuits, are generally not integrated on a chip owing to an enduring dependency on cumbersome connections, peripherals, and on computers for automation.8–11 Capillary microfluidics integrate energy supply and flow control onto a single chip by using capillary phenomena, but programmability remains rudimentary with at most a handful (eight) operations possible.12–19 Here we introduce mesoscopic microfluidic chain reactions (MCRs) base...

Background: Snakebite envenoming is a global health problem, mostly in tropical and subtropical countries. Bangladesh is a subtropical country facing thousands of snakebite envenoming death every year. Knowledge of the distribution of venomous snakes is necessary to identify snakebite-prone areas, develop strategies for prevention and management, and reduce venom-induced mortalities and morbidities. Methods: An integrated effort of direct observations of snakes, qualitative analysis of museum specimen records, clinical records of snakebites, and scholarly literature records were used to understand the pattern of distribution of venomous snakes in Bangladesh. Results: We enlist 65 venomous snake species from Bangladesh and present detailed documentation on their distribution pattern. However, only nine species were considered medically relevant species because of their venom potentiality to kill humans and available clinical records of envenomation. The distribution pattern of those ...

IntroductionAcute rheumatic fever (ARF) is usually considered a consequence of group A streptococcus (GAS) pharyngitis, with GAS skin infections not considered a major trigger. The aim was to quantify the risk of ARF following a GAS-positive skin or throat swab.MethodsThis retrospective analysis used pre-existing administrative data. Throat and skin swab data (1 866 981 swabs) from the Auckland region, New Zealand and antibiotic dispensing data were used (2010–2017). Incident ARF cases were identified using hospitalisation data (2010–2018). The risk ratio (RR) of ARF following swab collection was estimated across selected features and timeframes. Antibiotic dispensing data were linked to investigate whether this altered ARF risk following GAS detection.ResultsARF risk increased following GAS detection in a throat or skin swab. Māori and Pacific Peoples had the highest ARF risk 8–90 days following a GAS-positive throat or skin swab, compared with a GAS-negative swab. During this peri...

Malaria remains a major public health problem in Nigeria, that a positive, accurate and reliable microscopy or RDT should preferably be obtained before commencing treatment. High specificity will reduce unnecessary treatment with antimalarial drugs and improve the diagnosis. This study analyze the performance of microscopy and Rapid Diagnostic Techniques (RDT) used in the diagnosis of malaria at the University of Maiduguri Teaching Hospital, Maiduguri, Borno State, Nigeria from September to October, 2019. A total of 118 blood samples was screened for malaria by preparation of thick and thin film, Leishman staining and microscopic examination of the slides under oil immersion objectives. Rapid Diagnostic test (RDT) was performed using NADAL® Malaria 4 species test cassettes, with emphasis on falciparum malaria. The results shows that 65 patients (55.1%) were positive for malaria, out of which 42 (64.6%) were males, mainly (24.6%) within the young age group (1-10 years). Some of the p...

Background WW surveillance enables real time monitoring of SARS-CoV-2 burden in defined sewer catchment areas. Here, we assessed the occurrence of total, Delta and Omicron SARS-CoV-2 RNA in sewage from three tertiary-care hospitals in Calgary, Canada. Methods Nucleic acid was extracted from hospital (H) WW using the 4S-silica column method. H-1 and H-2 were assessed via a single autosampler whereas H-3 required three separate monitoring devices (a-c). SARS-CoV-2 RNA was quantified using two RT-qPCR approaches targeting the nucleocapsid gene; N1 and N200 assays, and the R203K/G204R and R203M mutations. Assays were positive if Cq< 40. Cross-correlation function analyses (CCF) was performed to determine the time-lagged relationships between WW signal and clinical cases. SARS-CoV-2 RNA abundance was compared to total hospitalized cases, nosocomial-acquired cases, and outbreaks. Statistical analyses were conducted using R. Results Ninety-six percent (188/196) of WW samples collected b...

Kajian ini melibatkan pemantauan perkembangan parasitemia dan taburan morfologi Plasmodium berghei sewaktu infeksi parasit dalam mencit, serta penentuan kesan infeksi P. berghei ke atas pengisyaratan MAP kinase eritrosit perumah. Analisis mikroskop ke atas slaid calitan ...

Spinal accessory nerve (SAN) injury results in loss of motor function of the trapezius muscle and leads to severe shoulder problems. Primary end-to-end or graft repair is usually the standard treatment. The authors present 2 patients who presented late (8 and 10 months) after their SAN injuries, in whom a lateral pectoral nerve transfer to the SAN was performed successfully using a supraclavicular approach.

Bone marrow aspiration (BMA) and biopsy (BMTB) are important investigations for diagnosis of haematolgical malignancies and non-malignant diseases both in adults and children. BMA and BMTB are complementary and if both are done a comprehensive analysis of bone marrow involvement is possible. 53 cases of BMTB were studied in order to underscore the indications and importance of BMTB. BMTB was done to determine cellularity in aplastic anaemia (AA) (33.96%, n=18) and in cases of failure of aspiration (32.08%, n=17). Failure of aspiration was attributable to bone marrow (BM) fibrosis (76%, n=13) due to acute leukaemia (35.30%, n=6) and myelofibrosis (43.17%, n=7). BMTB upstaged non Hodgkin’s lymphoma (NHL) from IIIB to IVB in 22.22% cases. 1 case of AA showed focal lymphoid aggregate which later evolved into acute lymphoblastic leukaemia (ALL). BMTB is a safe procedure and increased bleeding was noted only in a case of polycythaemia vera. DOI: http://dx.doi.org/10.3329/jdmc.v22i2.21544 ...

Background The diagnostic accuracy of unsupervised self-testing with rapid antigen diagnostic tests (Ag-RDTs) is mostly unknown. We studied the diagnostic accuracy of a self-performed SARS-CoV-2 saliva and nasal Ag-RDT in the general population. Methods This large cross-sectional study consecutively included unselected individuals aged $$\ge$$ ≥ 16 years presenting for SARS-CoV-2 testing at three public health service test sites. Participants underwent molecular test sampling and received two self-tests (the Hangzhou AllTest Biotech saliva self-test and the SD Biosensor nasal self-test by Roche Diagnostics) to perform themselves at home. Diagnostic accuracy of both self-tests was assessed with molecular testing as reference. Results Out of 2819 participants, 6.5% had a positive molecular test. Overall sensitivities were 46.7% (39.3–54.2%) for the saliva Ag-RDT and 68.9% (61.6–75.6%) for the nasal Ag-RDT. With a viral load cut-off (≥ 5.2 log10 SARS-CoV-2 E-gene copies/mL) as a proxy ...

Background Rapid antigen diagnostic tests (Ag-RDTs) are the most widely used point-of-care tests for detecting SARS-CoV-2 infection. Since the accuracy may have altered by changes in SARS-CoV-2 epidemiology, indications for testing, sampling and testing procedures, and roll-out of COVID-19 vaccination, we evaluated the performance of three prevailing SARS-CoV-2 Ag-RDTs. Methods In this cross-sectional study, we consecutively enrolled individuals aged >16 years presenting for SARS-CoV-2 testing at three Dutch public health service COVID-19 test sites. In the first phase, participants underwent either BD-Veritor System (Becton Dickinson), PanBio (Abbott), or SD-Biosensor (Roche Diagnostics) testing with routine sampling procedures. In a subsequent phase, participants underwent SD-Biosensor testing with a less invasive sampling method (combined oropharyngeal-nasal [OP-N] swab). Diagnostic accuracies were assessed against molecular testing. Results Six thousand nine hundred fifty-fiv...

BackgroundPre-/asymptomatic close contacts of SARS-CoV-2 infected individuals were tested at day 5 after contact by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Diagnostic accuracy of antigen-detecting rapid diagnostic tests (Ag-RDT) in pre-/asymptomatic close contacts was up till now unknown.MethodsWe performed a prospective cross-sectional diagnostic test accuracy study. Close contacts (e.g. selected via the test-and-trace program or contact tracing app) aged ≥16 years and asymptomatic when requesting a test, were included consecutively and tested at day 5 at four Dutch public health service test sites. We evaluated two Ag-RDTs (BD Veritor™ System Ag-RDT (BD), and Roche/SD Biosensor Ag-RDT (SD-B)) with RT-PCR as the reference standard. Virus culture was performed in RT-PCR positive individuals to determine the viral load cut-off above which 95% was culture positive, as a proxy of infectiousness.ResultsOf 2,678 BD-tested individuals, 233 (8.7%) were RT-PCR po...

BackgroundSARS-CoV-2 self-tests may lower the threshold of testing and produce a result quickly. This could support the early detection of infectious cases and reduce further community transmission. However, the diagnostic accuracy of (unsupervised) self-testing with rapid antigen diagnostic tests (Ag-RDTs) is mostly unknown. We therefore conducted a large-scale head-to-head comparison of the diagnostic accuracy of a self-performed SARS-CoV-2 saliva and nasal Ag-RDT, each compared to a molecular reference test, in the general population in the Netherlands.MethodsIn this cross-sectional study we consecutively included individuals aged 16 years and older presenting for SARS-CoV-2 testing at three Dutch public health service test sites irrespective of their indication for testing, vaccination status, and symptomatology. Participants were sampled for molecular testing at the test site and received two self-tests (the Hangzhou AllTest saliva self-test and the SD Biosensor nasal self-test...

We suggest an empirical rule-of-thumb for calculating the cross sections of charged-current quasielastic (CCQE) and CCQE-like interactions of neutrinos and antineutrinos with nuclei. The approach is based on the standard relativistic Fermi-gas model and on the notion of neutrino energy dependent axial-vector mass of the nucleon, governed by a couple of adjustable parameters, one of which is the conventional charged-current axial-vector mass. The inelastic background contributions and final-state interactions are therewith simulated using GENIE 3 neutrino event generator. An extensive comparison of our calculations with earlier and current accelerator CCQE and CCQE-like data for different nuclear targets shows good or at least qualitative overall agreement over a wide energy range. We also discuss some problematical issues common to several competing contemporary models of the CCQE (anti)neutrino–nucleus scattering and to the current neutrino interaction generators.

This study used epidemiological data of Chinese ferret-badger (CFB) rabies in eastern Taiwan, the Hualien County, from July 2013 to December 2020 to estimate its wave front spread rate. The first case of the CFB rabies virus in eastern Taiwan was detected in Zhuoxi Township in Hualien County on July 31, 2013. Our technique regressed TIME (months elapsed from the first case in Zhuoxi and the first case in each infected township invaded by the first case of CFB rabies) on DISTANCE (kilometers between locations of the first case in Zhuoxi and centroids of each infected township invaded by the first case of CFB rabies), using simple linear regression. The mean rate of wave front spread was 10.698 kilometers/year. The correlation between TIME and DISTANCE was R = 0.9273 at p = 0.0001. As CFB rabies has only occurred in China and Taiwan, studies on its epidemiology are extremely rare. This paper is the first study to estimate the wave front spread rate of CFB rabies in the world.