Virus tests to maximize availability of software systems

To determine the prevalence of testing for human immunodeficiency virus (HIV) antibody among adults with various risk factors for infection, particularly those residing in large metropolitan areas where the bulk of cases of acquired immunodeficiency syndrome (AIDS) have occurred. A nationwide, population-based telephone survey eliciting testing, sexual, and injection drug use histories. A total of 2673 randomly chosen US residents and 8263 randomly chosen residents of 23 metropolitan areas containing 64% of reported cases of AIDS. None. Testing for HIV antibody. Overall, rates of individuals ever tested were only slightly higher in the urban areas (23%) than in the nation as a whole (21%). Testing frequencies were low among all risk groups (less than 40%), except men engaging in same-sex sexual activity (60%) and male and female injection drug users (46% and 73%, respectively). The low rate of testing (35%) among the largest risk group, heterosexual men and women engaging in unprotected sexual intercourse with multiple partners, was particularly worrisome. To encourage antibody testing among the many at risk for infection who have not yet been tested, promotional campaigns should explain the universal susceptibility to infection among those at risk, and the availability of prophylactic medical therapies and social support services to persons who are HIV-seropositive. As there were comparable levels of risk-taking behavior among subjects in both samples, these campaigns must be designed to reach all segments of the population.

The High voltage static converter systems are deployed at different military and DoD assets in which power electronics is used for the isolated and stabilized AC or DC voltage/frequency conversion process and the Insulated Gate Bipolar Transistor (IGBT) triggering system plays crucial role in such systems. Such type of systems and equipments are being operated by the combat deployed personnel and they rely upon in order to complete their critical missions. Therefore, it is evident that reliability and availability during the mission and maintainability of the system before and after the mission is paramount. The objective of this paper is to present the predicted Reliability, Maintainability, Availability and Failure rate analysis of the IGBT triggering system. The analysis is made in the marine environment by defining specific parameters. The method used to calculate the reliability prediction of the IGBT triggering system is based on the calculation of Mean Time Between Failure (MTBF), which is obtained from the calculation of Failure rate of individual components used in the system. The maintainability analysis is done based on the length of the time required by the repairable components, repair through replaceable components or replacing the whole system. Therefore, this analysis will use the Mean Time To Repair (MTTR). MTBF and MTTR are used as key elements in the availability analysis of the system. Pareto analysis is presented in order to show the individual components failure rate contribution used in the system. The presented analysis shows the relationship between reliability, maintainability and availability of a system and also shows how the reliability and maintainability analysis improves the availability of the designed system. The presented analysis can be viewed with reference to system lifetime calculation as it will help in investment plan of designed system in marine environment.

Exascale systems will present considerable fault-tolerance challenges to applications and system software. These systems are expected to suffer several hard and soft errors per day. Unfortunately, many fault-tolerance methods in use, such as rollback recovery, are unsuitable for many expected errors, for example DRAM failures. As a result, applications will need to address these resilience challenges to more effectively utilize future systems. In this paper, we describe work on a cross-layer application/OS framework to handle uncorrected memory errors. We illustrate the use of this framework through its integration with a new fault-tolerant iterative solver within the Trilinos library, and present initial convergence results.

We sought to identify reasons for late human immunodeficiency virus (HIV) testing or late presentation for care. A structured chart review was performed to obtain data on test- and health-seeking behaviour of patients presenting late with CD4 cell counts below 350 cells/µl or with acquired immunodeficiency syndrome (AIDS), at the Zurich centre of the Swiss HIV Cohort Study between January 2009 and December 2011. Logistic regression analyses were used to compare demographic characteristics of persons presenting late with not late presenters. Of 281 patients, 45% presented late, 48% were chronically HIV-infected non-late presenters, and an additional 7% fulfilled the <350 CD4 cells/µl criterion for late presentation but a chart review revealed that lymphopenia was caused by acute HIV infection. Among the late presenters, 60% were first tested HIV positive in a private practice. More than half of the tests (60%) were suggested by a physician, only 7% following a specific risk situation. The majority (88%) of patients entered medical care within 1 month of testing HIV positive. Risk factors for late presentation were older age (odds ratio [OR] for ≥ 50 vs <30 years: 3.16, p = 0.017), Asian versus Caucasian ethnicity (OR 3.5, p = 0.021). Compared with men who have sex with men (MSM) without stable partnership, MSM in a stable partnership appeared less likely to present late (OR 0.50, p = 0.034), whereas heterosexual men in a stable partnership had a 2.72-fold increased odds to present late (p = 0.049). The frequency of late testing could be reduced by promoting awareness, particularly among older individuals and heterosexual men in stable partnerships.

Optimal checkpointing interval of a communication system with rollback recovery

Adenoviral transduction has the advantage of a strong and transient induction of the expression of the gene of interest into a broad variety of cell types and organs. However, recombinant adenoviral technology is laborious, time-consuming, and expensive. Here, we present an improved protocol using the pAdEasy system to obtain purified adenoviral particles that can induce a strong green fluorescent protein (GFP) expression in transduced cells. The advantages of this improved method are faster preparation and decreased production cost compared to the original method developed by Bert Vogelstein. The main steps of the adenoviral technology are: (1) the recombination of pAdTrack-GFP with the pAdEasy-1 plasmid in BJ5183 bacteria; (2) the packaging of the adenoviral particles; (3) the amplification of the adenovirus in AD293 cells; (4) the purification of the adenoviral particles from cell lysate and culture medium; and (5) the viral titration and functional testing of the adenovirus. The improvements to the original method consist of (i) the recombination in BJ5183-containing pAdEasy-1 by chemical transformation of bacteria; (ii) the selection of recombinant clones by “negative” and “positive” PCR; (iii) the transfection of AD293 cells using the K2 transfection system for adenoviral packaging; (iv) the precipitation with ammonium sulfate of the viral particles released by AD293 cells in cell culture medium; and (v) the purification of the virus by one-step cesium chloride discontinuous gradient ultracentrifugation. A strong expression of the gene of interest (in this case, GFP) was obtained in different types of transduced cells (such as hepatocytes, endothelial cells) from various sources (human, bovine, murine). Adenoviral-mediated gene transfer represents one of the main tools for developing modern gene therapies.

PurposeIn this paper, the objective is to perform mathematical modeling to optimize the steady-state availability of a multi-state repairable crushing system of a sugar plant using the evolutionary algorithm of Particle Swarm Optimization (PSO). The system availability is optimized by evaluating the optimal values of failure and repair rate parameters concerned with the subsystem of the system.Design/methodology/approachMathematical modeling of the multi-state repairable system is performed to develop the first-order differential equations based on the exponential distribution of the failure and repair rates. These differential equations are recursively solved to obtain the availability under normalizing conditions. The availability of the system is optimized by using the PSO algorithm. The results obtained by PSO are validated by using the Genetic Algorithm (GA).FindingsThe availability analysis of the system concludes that the cane preparation (F1) is critical of the crushing system and the optimized availability of the system using PSO is achieved as high as 87.12%.Originality/valueA crushing system of the sugar plant is evaluated as it is the main system of the sugar plant. The maintenance data associated with failure and repair rate parameters were analyzed with the help of maintenance records/logbook and by conducting personal meetings with maintenance executives of the plant. The results obtained in the paper helped them to plan maintenance strategies accordingly to get optimal system availability.

Intrahepatic cholestasis of pregnancy: Green-top Guideline No. 43 June 2022.

Objective To report the treatment of the first maternal patient infected with novel avian Influenza A (H5N6) virus in the world, and to investigate the clinical features and treatment of the maternal patient. Methods On December 28th, 2015, a maternal patient infected with H5N6 virus was admitted to the First Municipal Hospital of Zhaoqing City. The clinical features and treatments of this patient were analyzed. Results ① A 40-year-old female in 35-week gestation was admitted with the complaint of fever and cough for 6 days with the following characteristics: fever 6 days ago after getting a cold, mainly in the afternoon and night, the maximum body temperature was 39 ℃, with chills, shiver, single cough, short of breath after walking 50 meters which could be relieved after having a rest, but no expectoration, sore throat, nasal obstruction, rhinorrhea, chest tightness, chest pain, paroxysmal nocturnal dyspnea. The body temperature could be decreased after taking antibiotic and antipyretic which was prescribed by the doctor in the local hospital, and was repeatedly administrated. ② She had been to the local live poultry market before the onset of fever. ③ Auxiliary examination: on admission, the patient's blood test showed that the white blood cell count was normal (7.94×109/L), the neutrophil was normal (7.42×109/L), but the lymphocyte was low (0.44×109/L); it was shown by the arterial blood gas analysis that pH was 7.441, the oxygen partial pressure was 68.7 mmHg (1 mmHg = 0.133 kPa), and the carbon dioxide partial pressure was 23.9 mmHg. Infiltration was found in the lung by chest X-ray on the 2nd day, specifically, with double lung texture thickening, fuzzy, visible patchy fuzzy shadow, and double lung portal shadow. On the 3rd day, the throat swab specimen and sputum for virus nucleic acid detection of H7N9-RNA was negative, the H1N1-RNA was negative, but the avian influenza virus (AIV)-RNA was positive. The throat swab specimens and sputum for virus nucleic acid detection were performed by Disease Prevention Control Center of Zhaoqing City on the 4th day and by Disease Prevention Control Center of Guangdong Province on the 5th day, which showed positive H5N6-RNA, but her child's nasal swab specimens for AIV-RNA was negative on the 3rd day of birth. On the 5th day, blood influenza A virus antibody IgM was negative. ④ Treatment: a medium flow oxygen inhalation by nasal cannula was given after admission. On the 2nd day, the breath of the patient raised to 40 breaths/min, and the pulse oxygen saturation (SpO2) fell to 0.80, in order to avoid the fetal death because of hypoxemia, the patient was send for cesarean section, and invasive ventilation was given with 1.00 fraction of inspired oxygen (FiO2) in the intensive care unit (ICU) after the cesarean section, and the extracorporeal membrane oxygenation (ECMO) was given since the 4th day. 150 mg oseltamivir was given bid on the 4th day for 2 times a day, and it was changed to peramivir 600 mg everyday (qd) on the 6th day for 6 days, and oseltamivir 150 mg was given bid again on the 9th day for 14 days. ⑤ Outcome: the throat appeared red, and the tonsils were swollen, breath sounds on both sides was weak, but no rale or rhonchi was found at admission. But from the 2nd day fine rales were detectable in both sides of chest. The temperature was normal except on the 1st day (the maximum body temperature was 38.2 ℃), the 4th day (the maximum body temperature was 38 ℃), and the 10th day (the maximum body temperature was 37.5 ℃). The viral nucleic acid test of the throat swab specimen and sputum showed that the H5N6-RNA turned negative on the 9th day, the 10th day and the 11th day for 3 days. Pleural effusion was rapidly increased after the admission as shown by chest X-ray films, bilateral partial ground-glass opacities were observed in the low lung, and extended to all the lung fields on the 5th day, the bilateral lung infiltrations were absorbed slowly, and showed bilateral reticular opacities as the image of pulmonary fibrosis at last. The computed tomography scan of the chest showed bilateral irregular reticular opacities and basal discoid atelectasis on the 31st day. The color Doppler ultrasonography showed the systolic pressure of the pulmonary artery was about 78 mmHg on the 39th day. On the 49th day, norepinephrine was given for the hypotension, the serum creatinine (SCr) was 73.9 μmol/L; the SCr raised to 160.2 μmol/L on the 50th day, the urine output fell to less than 30 mL/h for 27 hours. Although the active antiviral, mechanical ventilation, ECMO and other therapies were prescribed, the patient eventually died due to multiple organ failure (MOF) on the 50th day. Conclusions The reported patient course was short, with an acute onset, with fever and cough as the chief complaint, and acute respiratory distress syndrome (ARDS) and MOF developed quickly. Her baby was born through cesarean delivery on the 2nd day after admission, and had not infected with H5N6 avian influenza. The clinical manifestations and the treatment strategy need to be further explored. Key words: H5N6 avian influenza A; Maternal; Anti-viral drug; Acute respiratory distress syndrome; Extracorporeal membrane oxygenation

Development of serological and nucleic acid testing (NAT) has revolutionized hepatitis C virus (HCV) diagnosis. Although third generation anti-HCV enzyme immunoassays (EIAs) are very effective for testing high prevalence populations, confirmatory testing is still necessary when these tests are applied to populations with a low HCV prevalence to exclude false positive results. Limitations of third generation anti-HCV EIAs include: the relatively prolonged time between acute infection and detection of seroconversion (which typically requires at least 5-6 weeks); delayed seroconversions in immunocompromised hosts (requiring months to years); and the inability of serological tests to confirm active HCV infection. In contrast, nucleic acid testing (NAT) can directly detect HCV RNA in serum, plasma or tissue and thereby confirm active infection as well as narrow the window between infection and HCV detection to as little as 1-2 weeks. Commercial NAT assays are now highly sensitive, specific, and reproducible and have largely replaced unreliable home brew nucleic acid amplification assays. Qualitative commercial NAT are typically more sensitive than quantitative assays and therefore the method of choice to confirm active infection. Given the efficacy of combination therapy with interferon/ribavirin and newer antiviral agents under development, HCV infection may become curable, which will likely impact future disease transmission. As the therapeutic costs are currently very high, there is clearly a need to assess the utility of quantitative NAT and to further evaluate the role of HCV genotyping to optimize antiviral therapy. Thus for the foreseeable future, a combination of both serological tests and NAT will be required for cost-effective HCV diagnosis and monitoring.

In the development of dynamic random access memory (DRAM) with a device size of 20 nm or less, the leakage current of a capacitor with high-k dielectrics is one of the main factors causing the failure of a device. To reduce the failure rate of the device, we conducted experiments to reduce the boron impurities, which form defect sites in the dielectrics of the capacitor. The boron source flux was reduced during the deposition process of the capping layer after the formation of the capacitor, and the actual boron concentration in the capping layer was measured by an atom probe tomography. The leakage current characteristics of the samples were confirmed through the dielectric leakage failure test, which is a mass production test technique. In addition, the resistance failure test was performed to measure the risk of increased resistance. From these results, it was confirmed that the failure rate due to the leakage current of the capacitor decreased linearly with reduced boron concentration and the increase in failure rate due to the cell node resistance was negligible. In addition, the results show that the failure rate of mass-produced DRAM products can be significantly reduced without any change in the structure or materials of the capacitor. This is expected to contribute greatly to the development of DRAM with dimensions on the scale of 20 nm or less.

This paper presents reliability, availability, and maintainability (RAM) analysis framework for evaluating the performance of a circulation system of water (WCS) used in a coal-fired power plant (CFPP). The performance of WCS is evaluated using a reliability block diagram (RBD), fault tree analysis (FTA), and Markov birth–death probabilistic approach. In this work, the system under study consists of five subsystems connected in series and parallel configuration namely condensate extraction pump (CEP), low-pressure feed water heater (LPH), deaerator (DR), boiler feed pump (BFP), high-pressure feed water heater (HPH). The reliability block diagram (RBD) and fault tree approach (FTA) have been employed for the performance evaluation of WCS. The Markov probabilistic approach based simulation model is developed. The transition diagram of the proposed model represented several states with full working capacity, reduced capacity, and failed state. The ranking of critical equipment is decided on the basis of criticality level of equipment. The study results revealed that the boiler feed pump affects the system availability at most, while the failure of deaerator affects it least. The availability of the system is optimized using the particle swarm optimization method. The optimized availability parameter (TBF, TTR) based modified maintenance strategy is recommended to enhance the availability of the plant system. The optimized failure rate and repair rate parameters of the subsystem are used to suggest a suitable maintenance strategy for the water circulation system of the thermal power plant. The proposed RAM framework helps the decision-makers to plan the maintenance activity as per the criticality level of subsystems and allocate the resources accordingly.

Classical swine fever (CSF) marker vaccine: Trial I. Challenge studies in weaner pigs

Polyoma BK virus nephropathy is a serious complication after renal transplantation and is associated with a high rate of allograft failure. Progressive infection with BK virus in immunocompromised renal transplant recipients occurs in detectable stages: Viruria, viremia, then nephropathy. In January, 2006, we initiated a plasma screening policy for all new transplant recipients, with monthly blood testing for BK virus by polymerase chain reaction (PCR). Between January 1, 2006, and February 28, 2007, 66 renal transplants were performed at our center. The 11 patients with a positive plasma BK PCR test underwent prompt reduction in baseline immunotherapy consisting of a 50% daily dose reduction (n = 6) or complete discontinuation of therapy with mycophenolate mofetil (n = 5). After reduction or discontinuation of mycophenolate mofetil, 10 patients became negative for BK virus in the plasma within 6 months. Progression to BK nephropathy has not occurred, and renal transplant dysfunction secondary to acute cellular rejection developed in only 1 patient (9%). One year post-transplant, the mean serum creatinine values for these 11 patients remained stable at 1.5 mg/dL. Monthly plasma screening for BK virus by PCR together with immunosuppressive regimen reduction prevents BK nephropathy. In addition, this intensive screening protocol is associated with a low rate of acute rejection and excellent preservation of renal function.

Reengineering of object-oriented software is not much grown area. It is difficult for the software managers when to decide for Reengineering software system. Software is delivered, it is corrected, and maintenance starts from the very beginning. Maintenance cost increases with time as requirements, technology and environment changes. The accumulated effects of maintenance make the system complex and quality of software decreases. As a result, maintenance cost increases rapidly. A situation comes when maintenance cost is too much high and it is difficult to maintain the system at such a high cost. This is a good time for reengineering the software system. If we do not reengineer the software system at this optimal time and go for high maintenance cost then complexity increases and system quality is worsen. It will be difficult to reengineer the system or reengineering cost is not justified as compared to the cost of new system. Software managers have no options except for having costly new software. Little efforts are done in this piece of work to escape this situation. Models of Decisive Point (right time for reengineering) are presented and it will help the software managers to reengineer the software system at most favorable time. Keywords: Object, reengineering zone, maintenance zone, decisive point, fine object, faulty object