Large-scale distributions of tropospheric nitric, formic, and acetic acids over the western Pacific basin during wintertime

We report here measurements of the acidic gases nitric (HNO3), formic (HCOOH), and acetic (CH3COOH) over the western Pacific basin during the February-March 1994 Pacific Exploratory Mission-West (PEM-West B). These data were obtained aboard the NASA DC-8 research aircraft as it flew missions in the altitude range of 0.3–12.5 km over equatorial regions near Guam and then further westward encompassing the entire Pacific Rim arc. Aged marine air over the equatorial Pacific generally exhibited mixing ratios of acidic gases \u3c100 parts per trillion by volume (pptv). Near the Asian continent, discrete plumes encountered below 6 km altitude contained up to 8 parts per billion by volume (ppbv) HNO3 and 10 ppbv HCOOH and CH3COOH. Overall there was a general correlation between mixing ratios of acidic gases with those of CO, C2H2, and C2Cl4, indicative of emissions from combustion and industrial sources. The latitudinal distributions of HNO3 and CO showed that the largest mixing ratios were centered around 15°N, while HCOOH, CH3COOH, and C2Cl4 peaked at 25°N. The mixing ratios of HCOOH and CH3COOH were highly correlated (r2 = 0.87) below 6 km altitude, with a slope (0.89) characteristic of the nongrowing season at midlatitudes in the northern hemisphere. Above 6 km altitude, HCOOH and CH3COOH were marginally correlated (r2 = 0.50), and plumes well defined by CO, C2H2, and C2Cl4 were depleted in acidic gases, most likely due to scavenging during vertical transport of air masses through convective cloud systems over the Asian continent. In stratospheric air masses, HNO3 mixing ratios were several parts per billion by volume (ppbv), yielding relationships with O3 and N2O consistent with those previously reported for NOy

Abstracts of the Second Urban Sound Symposium

Following the successful first Urban Sound Symposium held at Ghent University in 2019, the second edition in 2021 had to face the challenges of the pandemic. The symposium turned this challenge into an opportunity for giving easier access to practitioners and experts from around the globe who are confronted with urban sound in their professional activities. It was organized simultaneously in Ghent, Montreal, Nantes, Zurich, London and Berlin by researchers at Ghent University, Mc Gill University, Université Gustave Eiffel, EMPA, University College London and TU Berlin. The online event created opportunities for interaction between participants at poster-booths, virtual coffee tables, and included social activities

How do road traffic noise and residential greenness correlate with noise annoyance and long-term stress? Protocol and pilot study for a large field survey with a cross-sectional design

Urban areas are continuously growing, and densification is a frequent strategy to limit urban expansion. This generally entails a loss of green spaces (GSs) and an increase in noise pollution, which has negative effects on health. Within the research project RESTORE (Restorative potential of green spaces in noise-polluted environments), an extended cross-sectional field study in the city of Zurich, Switzerland, is conducted. The aim is to assess the relationship between noise annoyance and stress (self-perceived and physiological) as well as their association with road traffic noise and GSs. A representative stratified sample of participants from more than 5000 inhabitants will be contacted to complete an online survey. In addition to the self-reported stress identified by the questionnaire, hair cortisol and cortisone probes from a subsample of participants will be obtained to determine physiological stress. Participants are selected according to their dwelling location using a spatial analysis to determine exposure to different road traffic noise levels and access to GSs. Further, characteristics of individuals as well as acoustical and non-acoustical attributes of GSs are accounted for. This paper presents the study protocol and reports the first results of a pilot study to test the feasibility of the protocol

A prospective hospital-based study of the clinical impact of non-severe acute respiratory syndrome (Non-SARS)-related human coronavirus infection.

BACKGROUND: In addition to the human coronaviruses (HCoVs) OC43 and 229E, which have been known for decades to cause infection in humans, 2 new members of this genus have recently been identified: HCoVs NL63 and HKU1. Their impact as a cause of respiratory tract disease in adults at risk for complications needs to be established. METHODS: We prospectively assessed the clinical impact of coronavirus infection (excluding cases of severe acute respiratory syndrome) among hospitalized adults. All patients with respiratory disease for whom bronchoalveolar lavage was performed were screened by reverse-transcriptase polymerase chain reaction for the presence of all 4 HCoVs. RESULTS: HCoV was identified in 29 (5.4%) of 540 bronchoalveolar lavage fluid specimens from 279 subjects (mean age, 51 years; 63% male). HCoV OC43 was identified most frequently (12 isolates), followed by 229E (7 isolates), NL63 (6 isolates), and HKU1 (4 isolates). In all, 372 (69%) of 540 bronchoalveolar lavage fluid specimens were negative for bacteria, and 2 persons were coinfected with other respiratory viruses. Transplantation was the most common underlying condition. Of the 29 patients who had HCoV identified in their bronchoalveolar lavage fluid specimens, 9 (31%) were hospitalized in the intensive care unit, 22 (76%) presented to the hospital with acute respiratory symptoms, 16 (55%) presented with cough and/or sputum, 13 (45%) presented with dyspnea, 16 (55%) had experienced prior respiratory infection, and 18 (62%) had a new infiltrate that was visible on chest radiograph. The most frequent final diagnosis was a lower respiratory tract infection. CONCLUSIONS: The recently discovered HCoVs NL63 and HKU1 contribute significantly to the overall spectrum of coronavirus infection. Our study also suggests that coronaviruses contribute to respiratory symptoms in most cases

Novel Vaccines to Human Rabies

Rabies, the most fatal of all infectious diseases, remains a major public health problem in developing countries, claiming the lives of an estimated 55,000 people each year. Most fatal rabies cases, with more than half of them in children, result from dog bites and occur among low-income families in Southeast Asia and Africa. Safe and efficacious vaccines are available to prevent rabies. However, they have to be given repeatedly, three times for pre-exposure vaccination and four to five times for post-exposure prophylaxis (PEP). In cases of severe exposure, a regimen of vaccine combined with a rabies immunoglobulin (RIG) preparation is required. The high incidence of fatal rabies is linked to a lack of knowledge on the appropriate treatment of bite wounds, lack of access to costly PEP, and failure to follow up with repeat immunizations. New, more immunogenic but less costly rabies virus vaccines are needed to reduce the toll of rabies on human lives. A preventative vaccine used for the immunization of children, especially those in high incidence countries, would be expected to lower fatality rates. Such a vaccine would have to be inexpensive, safe, and provide sustained protection, preferably after a single dose. Novel regimens are also needed for PEP to reduce the need for the already scarce and costly RIG and to reduce the number of vaccine doses to one or two. In this review, the pipeline of new rabies vaccines that are in pre-clinical testing is provided and an opinion on those that might be best suited as potential replacements for the currently used vaccines is offered

Lower Semicontinuity in L1 of a Class of Functionals Defined on BV with Carathéodory Integrands

We prove lower semicontinuity in L1Ω for a class of functionals G:BVΩ⟶ℝ of the form Gu=∫Ωgx,∇udx+∫ΩψxdDsu where g:Ω×ℝN⟶ℝ, Ω⊂ℝN is open and bounded, g·,p∈L1Ω for each p, satisfies the linear growth condition limp⟶∞gx,p/p=ψx∈CΩ∩L∞Ω, and is convex in p depending only on p for a.e. x. Here, we recall for u∈BVΩ; the gradient measure Du=∇u dx+dDsux is decomposed into mutually singular measures ∇u dx and dDsux. As an example, we use this to prove that ∫Ωψxα2x+∇u2 dx+∫ΩψxdDsu is lower semicontinuous in L1Ω for any bounded continuous ψ and any α∈L1Ω. Under minor addtional assumptions on g, we then have the existence of minimizers of functionals to variational problems of the form Gu+u−u0L1 for the given u0∈L1Ω, due to the compactness of BVΩ in L1Ω

Lower Semicontinuity in <math xmlns="http://www.w3.org/1998/Math/MathML" id="M1"> <msup> <mrow> <mi>L</mi> </mrow> <mrow> <mn>1</mn> </mrow> </msup> </math> of a Class of Functionals Defined on <math xmlns="http://www.w3.org/1998/Math/MathML" id="M2"> <mi>B</mi> <mi>V</mi> </math> with Carathéodory Integrands

We prove lower semicontinuity in L 1 Ω for a class of functionals G : B V Ω ⟶ ℝ of the form G u = ∫ Ω g x , ∇ u d x + ∫ Ω ψ x d D s u where g : Ω × ℝ N ⟶ ℝ , Ω ⊂ ℝ N is open and bounded, g · , p ∈ L 1 Ω for each p , satisfies the linear growth condition lim p ⟶ ∞ g x , p / p = ψ x ∈ C Ω ∩ L ∞ Ω , and is convex in p depending only on p for a.e. x . Here, we recall for u ∈ B V Ω ; the gradient measure D u = ∇ u   d x + d D s u x is decomposed into mutually singular measures ∇ u   d x and d D s u x . As an example, we use this to prove that ∫ Ω ψ x α 2 x + ∇ u 2   d x + ∫ Ω ψ x d D s u is lower semicontinuous in L 1 Ω for any bounded continuous ψ and any α ∈ L 1 Ω . Under minor addtional assumptions on g , we then have the existence of minimizers of functionals to variational problems of the form G u + u − u 0 L 1 for the given u 0 ∈ L 1 Ω , due to the compactness of B V Ω in L 1 Ω </mfen

On time flows of minimizers of general convex functionals of linear growth with variable exponent in BV space and stability of pseudosolutions

AbstractHere we examine a method of selective smoothing in image restoration in BV space using a variable exponent functional of linear growth. Variable exponent growth was suggested in P. Blomgren et al. (1997) [6], and in Y. Chen et al. (2006) [8] the notion of a pseudosolution of the minimization problem is discussed, as well as the proof of existence and uniqueness of the solution of the time flow for the associated time dependent PDE. Here we prove stability for pseudosolutions, while also discussing the case for more general convex functionals of linear growth and variable exponent for use as an approximation for the time flow other than that which is used in Y. Chen et al. (2006) [8]