Efficient detection of contagious outbreaks in massive metropolitan encounter networks

Physical contact remains difficult to trace in large metropolitan networks, though it is a key vehicle for the transmission of contagious outbreaks. Co-presence encounters during daily transit use provide us with a city-scale time-resolved physical contact network, consisting of 1 billion contacts among 3 million transit users. Here, we study the advantage that knowledge of such co-presence structures may provide for early detection of contagious outbreaks. We first examine the "friend sensor" scheme --- a simple, but universal strategy requiring only local information --- and demonstrate that it provides significant early detection of simulated outbreaks. Taking advantage of the full network structure, we then identify advanced "global sensor sets", obtaining substantial early warning times savings over the friends sensor scheme. Individuals with highest number of encounters are the most efficient sensors, with performance comparable to individuals with the highest travel frequency, exploratory behavior and structural centrality. An efficiency balance emerges when testing the dependency on sensor size and evaluating sensor reliability; we find that substantial and reliable lead-time could be attained by monitoring only 0.01% of the population with the highest degree.Comment: 4 figure

Synthesis and Evaluation of Protein-Phenylboronic Acid Conjugates as Lectin Mimetics

Glycan-binding molecules, such as lectins, are very important tools for characterizing, imaging, or targeting glycans and are often involved in either physiological or pathological processes. However, their availability is far less compared to the diversity of native glycans. Therefore, development of lectin mimetics with desired specificity and affinity is in high demand. Boronic acid reacts with 1,2- and 1,3-diols of saccharides in aqueous media through reversible boronate ester formation and are regarded as synthetic lectin mimetics. In this study, bovine serum albumin (BSA)-phenylboronic acid (PBA) conjugates were synthesized in a density-controlled manner by targeting both aspartic and glutamic acids to afford lectin mimetics with multivalent PBA, as multivalency is a key factor for glycan recognition in both specificity and affinity. The resultant BSA-PBA conjugates were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. Their macrophage cell surface glycan-binding capacity was characterized by a competitive lectin-binding assay examined by flow cytometry, and 3-(4,5-di-methylthiazol-2-yl)-2,5 -diphenyltetrazolium bromide assay showed biocompatibility. These novel lectin mimetics will find a broad range of applications as they can be wittingly modified, altering binding specificity and capacity

Reduction in squamous cell carcinomas in mouse skin by dietary zinc supplementation.

Inadequate dietary Zn consumption increases susceptibility to esophageal and other cancers in humans and model organisms. Since Zn supplementation can prevent cancers in rodent squamous cell carcinoma (SCC) models, we were interested in determining if it could have a preventive effect in a rodent skin cancer model, as a preclinical basis for considering a role for Zn in prevention of human nonmelanoma skin cancers, the most frequent cancers in humans. We used the 7,12-dimethyl benzanthracene carcinogen/phorbol myristate acetate tumor promoter treatment method to induce skin tumors in Zn-sufficient wild-type and Fhit (human or mouse protein) knockout mice. Fhit protein expression is lost in \u3e50% of human cancers, including skin SCCs, and Fhit-deficient mice show increased sensitivity to carcinogen induction of tumors. We hypothesized that: (1) the skin cancer burdens would be reduced by Zn supplementation; (2) Fhit(-/-) (Fhit, murine fragile histidine triad gene) mice would show increased susceptibility to skin tumor induction versus wild-type mice. 30 weeks after initiating treatment, the tumor burden was increased ~2-fold in Fhit(-/-) versus wild-type mice (16.2 versus 7.6 tumors, P \u3c 0.001); Zn supplementation significantly reduced tumor burdens in Fhit(-/-) mice (males and females combined, 16.2 unsupplemented versus 10.3 supplemented, P = 0.001). Most importantly, the SCC burden was reduced after Zn supplementation in both strains and genders of mice, most significantly in the wild-type males (P = 0.035). Although the mechanism(s) of action of Zn supplementation in skin tumor prevention is not known in detail, the Zn-supplemented tumors showed evidence of reduced DNA damage and some cohorts showed reduced inflammation scores. The results suggest that mild Zn supplementation should be tested for prevention of skin cancer in high-risk human cohorts

Beam Splitter for Spin Waves in Quantum Spin Network

We theoretically design and analytically study a controllable beam splitter for the spin wave propagating in a star-shaped (e.g., a $Y$-shaped beam) spin network. Such a solid state beam splitter can display quantum interference and quantum entanglement by the well-aimed controls of interaction on nodes. It will enable an elementary interferometric device for scalable quantum information processing based on the solid system.Comment: 5 pages, 4 figures, derivation of formulae change

Repeated Plastic Stentings of Common Hepatic Duct for Portal Vein Aneurysm Compression in a Patient Unsuitable for Surgery

Portal vein aneurysms are rare vascular malformations with unclear etiologies and optimal treatment guidelines. Although Doppler ultrasonography is the most commonly used diagnostic tool, there is no gold standard imaging modality. Despite recommendations of surgical treatment for symptomatic aneurysms, there are limited options in the management of portal vein aneurysm-related complications in patients unfit for surgical intervention. We describe an 85-year-old man who presented with abdominal pain and low-grade fever with clinical signs consistent with cholangitis. Endoscopic retrograde cholangiopancreatography revealed a common hepatic duct stricture and concomitant intraductal ultrasonography identified adjacent aneurysmal portal vein dilatation. The final diagnosis of portal vein aneurysm was made using contrast computerized tomography scan. The patient was considered unsuitable for surgery due to his advanced age and multiple comorbidities. Instead, an endoscopic biliary plastic stent was inserted as a therapeutic alternative, which successfully achieved complete resolution of symptoms 3 days after the procedure. The patient was regularly followed at the outpatient clinic with repeated stent replacements every 3 to 4 months. After a follow-up of over 3.5 years, the patient remained symptom-free without signs of portal vein aneurysm compression. The result suggests that repeated stent replacements may be a therapeutic option for biliary compression by portal vein aneurysm in patients contraindicated for surgical intervention

1019-25 A Comparison of Preoperative Risk Factors for Early and Late Hospital Death in Cardiac Surgeries

Influence of preoperative risk factors on hospital mortality in cardiac surgeries has been investigated, but no one has identified differences in risk factors on early (postop day ≤ 2) and late death (postop day ≤ 3). To explore proper preventive strategies for each death, data were reviewed in 4351 adult patients who underwent cardiac surgery between 1/1/90 and 6/30/94. There were 93 (2.14%) early deaths and 171 (4.02%) late deaths in this series. Patients who died are older (early: 67.8 vs. 64.2, p=0.002; late: 71.1 vs. 63.9, p <0.001) Proportion of females is higher in late deaths (41.5% vs. 29.7%. p=0.001). but not in early deaths (32.3% vs. 30.2%, p=0.6). The early and late mortality are 1.65% and 2.78% for isolated CABGs (n=3037). 1.82% and 4.0% for isolated valves (n=713), 3.79% and 9.61% for CABG + valve (n=422), 7.82% and 12.73% for others (n=179). To adjust influence of preoperative risk factors on each type of death. stepwise logistic regression was applied.Early DeathLate DeathRisk FactorOdds RatiopRisk FactorOdds RatiopCardiac arrest5.98<0.001Cardiogenic shock6.93<0.001Refuse blood5.84<0.001Renal disease5.50<0.001Age≥ 85 years5.010.008CV disease4.08<0.001Emergency3.67<0.001MI <30 days3.360.004Re-operation2.85<0.001Cardiac arrest3.31<0.001Rheumatic dis.2.790.001Respiratory dis3.19<0.001Preop EF <35%2.71<0.001Liver disease3.040.051Hypotension2.260.009Age ≥ 75 years2.80<0.001MI < 10 days2.100.005Rheumatic dis2.190.002IABP support1.920.042Emergency1.560.035Age 65–64 years1.770.017Heart Failure1.480.050Diabetes1.470.055Chronic Isch. HD0.37<0.001Conclusions(1) Acute cardiac factors dominate early mortality. (2) Chronic organ system function is more important in late deaths than in early deaths. (3) Risk adjusted mortality does not differ significantly in genders

The relationship between substructure in 2D X-ray surface brightness images and weak lensing mass maps of galaxy clusters: A simulation study

In this paper, we undertake a study to determine what insight can be reliably gleaned from the comparison of the X-ray and the weak lensing mass maps of galaxy clusters. We do this by investigating the 2D substructure within three high-resolution cosmological simulations of galaxy clusters. Our main results focus on non-radiative gas dynamics, but we also consider the effects of radiative cooling at high redshift. For our analysis, we use a novel approach, based on unsharp-masking, to identify substructures in 2D surface mass density and X-ray surface brightness maps. At full resolution (~ 15 h^-1 kpc), this technique is capable of identifying almost all self-bound dark matter subhaloes with M>10^12 h^-1 M_sun. We also report a correlation between the mass of a subhalo and the area of its corresponding 2D detection; such a correlation, once calibrated, could provide a useful estimator for substructure mass. Comparing our 2D mass and X-ray substructures, we find a surprising number of cases where the matching fails: around one third of galaxy-sized substructures have no X-ray counterpart. Some interesting cases are also found at larger masses, in particular the cores of merging clusters where the situation can be complex. Finally, we degrade our mass maps to what is currently achievable with weak-lensing observations (~100 h^-1 kpc at z=0.2). While the completeness mass limit increases by around an order of magnitude, a mass-area correlation remains. Our paper clearly demonstrates that the next generation of lensing surveys should start to reveal a wealth of information on cluster substructure. (Abridged)Comment: 30 pages, 27 figures, 3 tables. Accepted for publication in MNRAS. High resolution version available at http://www.physics.ox.ac.uk/users/powell/clustersubs_highres.pd

Treatment of oil-water emulsion from the machinery industry by Fenton’s reagent

An oil–water emulsion from the machinery industry was treated using Fenton\u27s reagent. The objective was to reduce the high chemical oxygen demand (COD) of this waste stream so that it would meet the COD effluent limit of Chinese Standard JS-7740-95. The optimal [H2O2]/[Fe2+] ratio for COD removal was 3. An orthogonal experimental design was developed based on the optimal [H2O2]/[Fe2+] ratio to evaluate the significance of four parameters relevant to the treatment process, namely, H2O2 dosage, initial pH, oxidation time and coagulation pH. The influence of the four parameters on COD removal efficiency decreased as follows: H2O2 dosage \u3e oxidation time \u3e coagulation pH \u3e initial pH. The COD removal efficiency was further investigated based on the most important single-factor parameter, which was H2O2 dosage, as discovered in the orthogonal test. A well-fitted empirical correlation was obtained from the single-factor analysis and up to 98% COD removal was attained using 50 mM H2O2. Using the doses and conditions identified in this study, the treated oil–water emulsion can be discharged according to Chinese Standard JS-7740-95