A kinematic wave theory of capacity drop

Capacity drop at active bottlenecks is one of the most puzzling traffic phenomena, but a thorough understanding is practically important for designing variable speed limit and ramp metering strategies. In this study, we attempt to develop a simple model of capacity drop within the framework of kinematic wave theory based on the observation that capacity drop occurs when an upstream queue forms at an active bottleneck. In addition, we assume that the fundamental diagrams are continuous in steady states. This assumption is consistent with observations and can avoid unrealistic infinite characteristic wave speeds in discontinuous fundamental diagrams. A core component of the new model is an entropy condition defined by a discontinuous boundary flux function. For a lane-drop area, we demonstrate that the model is well-defined, and its Riemann problem can be uniquely solved. We theoretically discuss traffic stability with this model subject to perturbations in density, upstream demand, and downstream supply. We clarify that discontinuous flow-density relations, or so-called "discontinuous" fundamental diagrams, are caused by incomplete observations of traffic states. Theoretical results are consistent with observations in the literature and are verified by numerical simulations and empirical observations. We finally discuss potential applications and future studies.Comment: 29 pages, 10 figure

Different Types of Housing and Respiratory Health Outcomes

Evidence has shown that housing conditions may substantially influence the health of residents. Different types of housing have different structures and construction materials, which may affect indoor environment and housing conditions. This study aimed to investigate whether people living in different types of housing have different respiratory health outcomes. The data from the 1999–2006 National Health and Nutrition Examination Survey were used for the analyses. The types of housing included houses, townhouses, apartments, and mobile homes. Respiratory symptoms included wheezing, coughing, sputum, and dyspnea; respiratory diseases included asthma, chronic bronchitis, emphysema, and chronic obstructive pulmonary disease (COPD). Multiple logistic regression was used to calculate odds ratio (OR) and 95% confidence interval (CI) after adjustment for potential confounding factors. A total of 11,785 participants aged 40 years and older were included in the analyses. Compared with those living in single family houses, participants living in mobile homes were more likely to have respiratory conditions, the OR (95% CI) was 1.38 (1.13–1.69) for wheezing, and 1.49 (1.25–1.78) for dyspnea; whereas participants living in apartments were less likely to have respiratory conditions, the OR (95% CI) was 0.58 (0.36–0.91) for chronic bronchitis, and 0.69 (0.49–0.97) for COPD. Compared with living in single family houses, living in mobile home was associated with worse, whereas living in apartments was associated with better, respiratory health outcomes. Further research is needed to better understand the underlying mechanisms and prevent adverse respiratory effects associated with living in mobile homes

Effects of the endoparasitoid Cotesia chilonis (Hymenoptera: Braconidae) parasitism, venom, and calyx fluid on cellular and humoral immunity of its host Chilo suppressalis (Lepidoptera: Crambidae) larvae

AbstractThe larval endoparasitoid Cotesia chilonis injects venom and bracoviruses into its host Chilo suppressalis during oviposition. Here we study the effects of the polydnavirus (PDV)-carrying endoparasitoid C. chilonis (Hymenoptera: Braconidae) parasitism, venom and calyx fluid on host cellular and humoral immunity, specifically hemocyte composition, cellular spreading, encapsulation and melanization. Total hemocyte counts (THCs) were higher in parasitized larvae than in unparasitized larvae in the late stages following parasitization. While both plasmatocyte and granulocyte fractions and hemocyte mortality did not differ between parasitized and unparasitized hosts, in vitro spreading behavior of hemocytes was inhibited significantly by parasitism throughout the course of parasitoid development. C. chilonis parasitism suppressed the encapsulation response and melanization in the early stages. Venom alone did not alter cellular immune responses, including effects on THCs, mortality, hemocyte composition, cell spreading and encapsulation, but venom did inhibit humoral immunity by reducing melanization within 6h after injection. In contrast to venom, calyx fluid had a significant effect on cell spreading, encapsulation and melanization from 6h after injection. Dose–response injection studies indicated the effects of venom and calyx fluid synergized, showing a stronger and more persistent reduction in immune system responses than the effect of either injected alone

The unidirectional valve patch provides no benefits to early and long-term survival in patients with ventricular septal defect and severe pulmonary artery hypertension

ObjectiveOur aim was to test whether a unidirectional valve patch would provide benefit to early and long-term survival for patients with ventricular septal defect and severe pulmonary artery hypertension.MethodsEight hundred seventy-six cases of ventricular septal defect with severe pulmonary artery hypertension were closed with or without a unidirectional valve patch and were classified as the unidirectional valve patch (UVP) group (n = 195) and nonvalve patch (NVP) group (n = 681), respectively. Propensity scores of inclusion into the UVP group were used to match 138 pairs between the 2 groups. Kaplan–Meier survival curves were constructed to compare early and long-term survival.ResultsFor the 138 propensity-matched pairs, there were 7 and 9 early deaths (in-hospital deaths) in the UVP and NVP groups, respectively. The difference in early mortality between the 2 groups did not reach statistical significance (χ2 = 0.265, P = .6064). With a mean of 9.2 ± 4.92 years' and 2511 patient-years' follow-up, there were 6 late deaths in the UVP group and 7 late deaths in the NVP group. The difference in actuarial survival at 5, 10, 15, and 18 years between the 2 groups was not significant (log-rank test, χ2 = 0.565, P = .331). The difference in the late mortality between the groups with or without a patent patch at the time of discharge did not reach statistical significance (χ2 = 1.140, P = .2856). There was no difference between the 2 groups in the 6-minute walk distance assessed at the last follow-up (525.9 ± 88.0 meters for the UVP group and 536.5 ± 95.8 meters for the NVP group, F = 1.550, P = .214).ConclusionA unidirectional valve patch provides no benefits to early and long-term survival when it is used to deal with ventricular septal defect and severe pulmonary artery hypertension

A Generalized Robust Minimization Framework for Low-Rank Matrix Recovery

This paper considers the problem of recovering low-rank matrices which are heavily corrupted by outliers or large errors. To improve the robustness of existing recovery methods, the problem is solved by formulating it as a generalized nonsmooth nonconvex minimization functional via exploiting the Schatten p-norm (0 < p ≤1) and Lq(0 < q ≤1) seminorm. Two numerical algorithms are provided based on the augmented Lagrange multiplier (ALM) and accelerated proximal gradient (APG) methods as well as efficient root-finder strategies. Experimental results demonstrate that the proposed generalized approach is more inclusive and effective compared with state-of-the-art methods, either convex or nonconvex

Puerarin attenuates pressure overload-induced cardiac hypertrophy

AbstractBackgroundPuerarin is the most abundant isoflavonoid in kudzu root. It has been used to treat angina pectoris and myocardial infarction clinically. However, little is known about the effect of puerarin on cardiac hypertrophy.MethodsAortic banding (AB) was performed to induce cardiac hypertrophy in mice. Puerarin premixed in diets was administered to mice after one week of AB. Echocardiography and catheter-based measurements of hemodynamic parameters were performed at 7 weeks after starting puerarin treatment (8 weeks post-surgery). The extent of cardiac hypertrophy was also evaluated by pathological and molecular analyses of heart samples. Cardiomyocyte apoptosis was assessed by measuring Bax and Bcl-2 protein expression and terminal deoxynucleotidyl transferase dUTP nick end labeling staining. In addition, the inhibitory effect of puerarin (1μM, 5μM, 10μM, 20μM, 40μM) on mRNA expression of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) in Ang II (1μM)-stimulated H9c2 cells was investigated using quantitative real-time reverse transcription-polymerase chain reaction.ResultsEchocardiography and catheter-based measurements of hemodynamic parameters at 7 weeks revealed the amelioration of systolic and diastolic abnormalities. Puerarin also decreased cardiac fibrosis in AB mice. Moreover, the beneficial effect of puerarin was associated with the normalization in gene expression of hypertrophic and fibrotic markers. Further studies showed that pressure overload significantly induced the activation of phosphoinositide 3-kinase (PI3K)/Akt signaling and c-Jun N-terminal kinase (JNK) signaling, which was blocked by puerarin treatment. Cardiomyocyte apoptosis and induction of Bax in response to AB were suppressed by puerarin. Furthermore, the increased mRNA expression of ANP and BNP induced by Ang II (1μM) was restrained to a different extent by different concentrations of puerarin.ConclusionPuerarin may have an ability to retard the progression of cardiac hypertrophy and apoptosis which is probably mediated by the blockade of PI3K/Akt and JNK signaling pathways

Clinical and laboratory features of PCR-confirmed periocular tuberculosis in China

Experts lack knowledge of periocular tuberculosis (TB) in China. Nested polymerase chain reaction (PCR) shows advantages in diagnosis of extrapulmonary TB. Our study aims to explore the clinical and laboratory features of PCR-confirmed periocular TB. We retrospectively reviewed medical records of presumptive periocular TB and performed nested PCR test to confirm diagnosis. Nine cases were recruited. Clinical symptoms were chronic and insidious. Eight cases achieved favorable visual acuity, while one underwent enucleation due to fungal-TB panophthalmitis. Sensitivity of caseous necrosis, acid-fast bacilli (AFB) staining and interferon γ release assay (T-SPOT) test are 33.3%, 44.4% and 85.7% respectively. Low lymphocyte percentage (P=0.019) and high monocyte-lymphocyte ratio (P=0.042) positively correlate with AFB staining. Male gender (P=0.048) and Langhans giant cell (P=0.048) positively correlate with caseous necrosis. To conclude, traditional TB ancillary tests are not as sensitive as nested PCR technique. Several factors facilitate diagnosis including male gender, decreased lymphocytes, and typical Langhans giant cells

α-Glucosidase Inhibitory Effect and Simultaneous Quantification of Three Major Flavonoid Glycosides in Microctis folium

FWN – Publicaties zonder aanstelling Universiteit Leide

The activation of GABAergic neurons in the hypothalamic tuberomammillary nucleus attenuates sevoflurane and propofol-induced anesthesia in mice

Background: The histaminergic neurons in the hypothalamic tuberomammillary nucleus (TMN) have been suggested to play a vital role in maintaining a rising state. But the neuronal types of the TMN are in debate and the role of GABAergic neurons remains unclear.Methods: In the present study, we examined the role of TMN GABAergic neurons in general anesthesia using chemogenetics and optogenetics strategies to regulate the activity of TMN GABAergic neurons.Results: The results indicated that either chemogenetic or optogenetic activation of TMN GABAergic neurons in mice decreased the effect of sevoflurane and propofol anesthesia. In contrast, inhibition of the TMN GABAergic neurons facilitates the sevoflurane anesthesia effect.Conclusion: Our results suggest that the activity of TMN GABAergic neurons produces an anti-anesthesia effect in loss of consciousness and analgesia