Extra processors versus future information in optimal deadline scheduling

This paper is concerned with the extra-resource analysis of online scheduling algorithms. In particular, it studies how to make use of multiple processors to counteract the lack of future information in online deadline scheduling. Our results extend the previous work that are primarily based on using a faster processor to obtain a performance guarantee. The challenge arises from the fact that jobs are sequential in nature and cannot be executed on more than one processor at the same time. Thus, a faster processor can speed up a job while multiple unit-speed processors cannot help.postprin

Competitive deadline scheduling via additional or faster processors

This paper studies on-line scheduling in a single-processor system that allows preemption. The aim is to maximize the total value of jobs completed by their deadlines. It is known that if the on-line scheduler is given a processor faster (say, two times faster) than the off-line scheduler, then there exists an on-line algorithm called SLACKER that can achieve an O(1) competitive ratio. In this paper, we show that using additional unit-speed processors instead of a faster processor is a possible but not cost effective way to achieve an O(1) competitive ratio. Specifically, we find that-θ(log k) unit-speed processors are required, where k is the importance ratio. Another contribution of this paper is an improved analysis of the competitiveness of SLACKER; this new analysis enables us to show that SLACKER, when extended to multi-processor systems, can still guarantee an O(1) competitive ratio.postprin

Frequency-domain multiscale quantum mechanics/electromagnetics simulation method

A frequency-domain quantum mechanics and electromagnetics (QM∕EM) method is developed. Compared with the time-domain QM/EM method [Meng et al., J. Chem. Theory Comput. 8, 1190-1199 (2012)], the newly developed frequency-domain QM∕EM method could effectively capture the dynamic properties of electronic devices over a broader range of operating frequencies. The system is divided into QM and EM regions and solved in a self-consistent manner via updating the boundary conditions at the QM and EM interface. The calculated potential distributions and current densities at the interface are taken as the boundary conditions for the QM and EM calculations, respectively, which facilitate the information exchange between the QM and EM calculations and ensure that the potential, charge, and current distributions are continuous across the QM/EM interface. Via Fourier transformation, the dynamic admittance calculated from the time-domain and frequency-domain QM/EM methods is compared for a carbon nanotube based molecular device.published_or_final_versio

Lipid profiles and outcomes of patients with prior cancer and subsequent myocardial infarction or stroke

Patients with cancer are at increased risk of myocardial infarction (MI) and stroke. Guidelines do not address lipid profile targets for these patients. Within the lipid profiles, we hypothesized that patients with cancer develop MI or stroke at lower low density lipoprotein cholesterol (LDL-C) concentrations than patients without cancer and suffer worse outcomes. We linked nationwide longitudinal MI, stroke and cancer registries from years 2007-2017. We identified 42,148 eligible patients with MI (2421 prior cancer; 39,727 no cancer) and 43,888 eligible patients with stroke (3152 prior cancer; 40,738 no cancer). Median LDL-C concentration was lower in the prior cancer group than the no cancer group at incident MI [2.43 versus 3.10 mmol/L, adjusted ratio 0.87 (95% CI 0.85-0.89)] and stroke [2.81 versus 3.22 mmol/L, adjusted ratio 0.93, 95% CI 0.91-0.95)]. Similarly, median triglyceride and total cholesterol concentrations were lower in the prior cancer group, with no difference in high density lipoprotein cholesterol. Prior cancer was associated with higher post-MI mortality [adjusted hazard ratio (HR) 1.48, 95% CI 1.37-1.59] and post-stroke mortality (adjusted HR 1.95, 95% CI 1.52-2.52). Despite lower LDL-C concentrations, patients with prior cancer had worse post-MI and stroke mortality than patients without cancer

Targeting TAO kinases using a new inhibitor compound delays mitosis and induces mitotic cell death in centrosome amplified breast cells

Thousand-and-one amino acid kinases (TAOKs) 1 and 2 are activated catalytically during mitosis and can contribute to mitotic cell rounding and spindle positioning. Here, we characterize a compound that inhibits TAOK1 and TAOK2 activity with IC50 values of 11-15 nM, is ATP-competitive and targets these kinases selectively. TAOK inhibition or depletion in centrosome amplified SKBR3 or BT549 breast cancer cell models increases the mitotic population, the percentages of mitotic cells displaying amplified centrosomes and multipolar spindles, induces cell death and inhibits cell growth. In contrast, non-tumorigenic and dividing bipolar MCF-10A breast cells appear less dependent on TAOK activity and can complete mitosis and proliferate in the presence of the TAOK inhibitor. We demonstrate that TAOK1 and TAOK2 localize to the cytoplasm and centrosomes respectively during mitosis. Live cell imaging shows that the TAOK inhibitor prolongs the duration of mitosis in SKBR3 cells, increases mitotic cell death and reduces the percentages of cells exiting mitosis, whereas MCF-10A cells continue to divide and proliferate. Over 80% of breast cancer tissues display supernumerary centrosomes and tumor cells frequently cluster extra centrosomes to avoid multipolar mitoses and associated cell death. Consequently, drugs that stimulate centrosome declustering and induce multipolarity are likely to target dividing centrosome amplified cancer cells preferentially, whilst sparing normal bipolar cells. Our results demonstrate that TAOK inhibition can enhance centrosome declustering and mitotic catastrophe in cancer cells and these proteins may therefore offer novel therapeutic targets suitable for drug inhibition and the potential treatment of breast cancers, where supernumerary centrosomes occur

Home exposure to Arabian incense (bakhour) and asthma symptoms in children: a community survey in two regions in Oman

<p>Abstract</p> <p>Background</p> <p>Incense burning has been reported to adversely affect respiratory health. The aim of this study was to explore whether exposure to bakhour contributes to the prevalence of asthma and/or triggers its symptoms in Omani children by comparing two Omani regions with different prevalence of asthma.</p> <p>Methods</p> <p>A randomly selected sample of 10 years old schoolchildren were surveyed using an Arabic version of ISAAC Phase II questionnaires with the addition of questions concerning the use and effect of Arabian incense on asthma symptoms. Current asthma was defined as positive response to wheeze in the past 12 months or positive response to "ever had asthma" together with a positive response to exercise wheeze or night cough in the past 12 months. Simple and multivariable logistic regression analyses were performed to estimate the effect of bakhour exposure and other variables on current asthma diagnosis and parents' response to the question: "Does exposure to bakhour affect your child breathing?"</p> <p>Results</p> <p>Of the 2441 surveyed children, 15.4% had current asthma. Bakhour use more than twice a week was three times more likely to affect child breathing compared to no bakhour use (adjusted OR 3.01; 95% CI 2.23–4.08) and this effect was 2.55 times higher in asthmatics (adjusted OR 2.55; 95% CI 1.97–3.31) compared to non-asthmatics. In addition, bakhour caused worsening of wheeze in 38% of the asthmatics, making it the fourth most common trigger factor after dust (49.2%), weather (47.6%) and respiratory tract infections (42.2%). However, there was no significant association between bakhour use and the prevalence of current asthma (adjusted OR 0.87; 95% CI 0.63–1.20).</p> <p>Conclusion</p> <p>Arabian incense burning is a common trigger of wheezing among asthmatic children in Oman. However, it is not associated with the prevalence asthma.</p

The extraordinary evolutionary history of the reticuloendotheliosis viruses

The reticuloendotheliosis viruses (REVs) comprise several closely related amphotropic retroviruses isolated from birds. These viruses exhibit several highly unusual characteristics that have not so far been adequately explained, including their extremely close relationship to mammalian retroviruses, and their presence as endogenous sequences within the genomes of certain large DNA viruses. We present evidence for an iatrogenic origin of REVs that accounts for these phenomena. Firstly, we identify endogenous retroviral fossils in mammalian genomes that share a unique recombinant structure with REVs—unequivocally demonstrating that REVs derive directly from mammalian retroviruses. Secondly, through sequencing of archived REV isolates, we confirm that contaminated Plasmodium lophurae stocks have been the source of multiple REV outbreaks in experimentally infected birds. Finally, we show that both phylogenetic and historical evidence support a scenario wherein REVs originated as mammalian retroviruses that were accidentally introduced into avian hosts in the late 1930s, during experimental studies of P. lophurae, and subsequently integrated into the fowlpox virus (FWPV) and gallid herpesvirus type 2 (GHV-2) genomes, generating recombinant DNA viruses that now circulate in wild birds and poultry. Our findings provide a novel perspective on the origin and evolution of REV, and indicate that horizontal gene transfer between virus families can expand the impact of iatrogenic transmission events

Thoracic empyema: a 12 year experience from a UK tertiary cardiothoracic Centre

Background Empyema is an increasingly frequent clinical problem worldwide, and has substantial morbidity and mortality. Our objectives were to identify the clinical, surgical and microbiological features, and management outcomes, of empyema. Methods A retrospective observational study over 12 years (1999–2010) was carried out at The Heart Hospital, London, United Kingdom. Patients with empyema were identified by screening the hospital electronic ‘Clinical Data Repository’. Demographics, clinical and microbiological characteristics, underlying risk factors, peri-operative blood tests, treatment and outcomes were identified. Univariable and multivariable statistical analyses were performed. Results Patients (n = 406) were predominantly male (74.1%); median age = 53 years (IQR = 37–69). Most empyema were community-acquired (87.4%) and right-sided (57.4%). Microbiological diagnosis was obtained in 229 (56.4%) patients, and included streptococci (16.3%), staphylococci (15.5%), Gram-negative organisms (8.9%), anaerobes (5.7%), pseudomonads (4.4%) and mycobacteria (9.1%); 8.4% were polymicrobial. Most (68%) cases were managed by open thoracotomy and decortication. Video-assisted thoracoscopic surgery (VATS) reduced hospitalisation from 10 to seven days (P = 0.0005). All-cause complication rate was 25.1%, and 28 day mortality 5.7%. Predictors of early mortality included: older age (P = 0.006), major co-morbidity (P = 0.01), malnutrition (P = 0.001), elevated red cell distribution width (RDW, P<0.001) and serum alkaline phosphatase (P = 0.004), and reduced serum albumin (P = 0.01) and haemoglobin (P = 0.04). Conclusions Empyema remains an important cause of morbidity and hospital admissions. Microbiological diagnosis was only achieved in just over 50% of cases, and tuberculosis is a notable causative organism. Treatment of empyema with VATS may reduce duration of hospital stay. Raised RDW appears to associate with early mortality

Incense smoke: clinical, structural and molecular effects on airway disease

In Asian countries where the Buddhism and Taoism are mainstream religions, incense burning is a daily practice. A typical composition of stick incense consists of 21% (by weight) of herbal and wood powder, 35% of fragrance material, 11% of adhesive powder, and 33% of bamboo stick. Incense smoke (fumes) contains particulate matter (PM), gas products and many organic compounds. On average, incense burning produces particulates greater than 45 mg/g burned as compared to 10 mg/g burned for cigarettes. The gas products from burning incense include CO, CO2, NO2, SO2, and others. Incense burning also produces volatile organic compounds, such as benzene, toluene, and xylenes, as well as aldehydes and polycyclic aromatic hydrocarbons (PAHs). The air pollution in and around various temples has been documented to have harmful effects on health. When incense smoke pollutants are inhaled, they cause respiratory system dysfunction. Incense smoke is a risk factor for elevated cord blood IgE levels and has been indicated to cause allergic contact dermatitis. Incense smoke also has been associated with neoplasm and extracts of particulate matter from incense smoke are found to be mutagenic in the Ames Salmonella test with TA98 and activation. In order to prevent airway disease and other health problem, it is advisable that people should reduce the exposure time when they worship at the temple with heavy incense smokes, and ventilate their house when they burn incense at home