Background
The clinical characteristics of novel coronavirus disease (COVID‐2019) patients outside the epicenter of Hubei Province are less understood.
Methods
We analyzed the epidemiological and ...clinical features of all COVID‐2019 cases in the only referral hospital in Shenzhen City, China, from January 11, 2020, to February 6, 2020, and followed until March 6, 2020.
Results
Among the 298 confirmed cases, 233 (81.5%) had been to Hubei, while 42 (14%) did not have a clear travel history. Only 218 (73.15%) cases had a fever as the initial symptom. Compared with the nonsevere cases, severe cases were associated with older age, those with underlying diseases, and higher levels of C‐reactive protein, interleukin‐6, and erythrocyte sedimentation rate. Slower clearance of the virus was associated with a higher risk of progression to critical condition. As of March 6, 2020, 268 (89.9%) patients were discharged and the overall case fatality ratio was 1.0%.
Conclusions
In a designated hospital outside Hubei Province, COVID‐2019 patients could be effectively managed by properly using the existing hospital system. Mortality may be lowered when cases are relatively mild, and there are sufficient medical resources to care and treat the disease.
This study analyzes the epidemiological and clinical features of all 298 COVID‐19 cases in the only referral hospital of Shenzhen City. Slower clearance of virus is associated with a higher progression to severe critical condition. Compared with the nonsevere cases, severe cases are associated with older age, underlying diseases, higher levels of C‐reactive protein, interleukin‐6, and erythrocyte sedimentation rate. Abbreviations: CRP, C‐reactive protein; ESR, erythrocyte sedimentation rate.
Children’s respiratory health are particularly vulnerable to outdoor air pollution, but evidence is lacking on the very acute effects of air pollution on the risk of acute upper respiratory ...infections (AURI) and acute lower respiratory infections (ALRI) in children. This study aimed to evaluate the risk of cause-specific AURI and ALRI, in children within 24 h of exposure to air pollution. We obtained data on emergency cases, including 11,091 AURI cases (acute pharyngitis, acute tonsillitis, acute obstructive laryngitis and epiglottitis, and unspecified acute upper respiratory infections) and 11,401 ALRI cases (pneumonia, acute bronchitis, acute bronchiolitis, unspecified acute lower respiratory infection) in Brisbane, Australia, 2013–2015. A time-stratified case-crossover analysis was used to examine the hourly association of AURI and ALRI with high concentration (95th percentile) of four air pollutants (particulate matters with aerodynamic diameter <10 μm (PM10) and <2.5 μm (PM2.5), ozone (O3), nitrogen dioxide (NO2)). We observed increased risk of acute tonsillitis associated with PM2.5 within 13–24 h (odds ratio (OR), 1.45; 95% confidence interval CI, 1.02–2.06) and increased risk of unspecified acute upper respiratory infections related to O3 within 2–6 h (OR, 1.38, 95%CI, 1.12–1.70), NO2 within 1 h (OR, 1.19; 95%CI, 1.01–1.40), and PM2.5 within 7–12 h (OR, 1.21; 95%CI, 1.02–1.43). Cold season and nigh-time air pollution has greater effects on AURI, whereas greater risk of ALRI was seen in warm season and daytime. Our findings suggest exposures to particulate and gaseous air pollution may transiently increase risk of AURI and ALRI in children within 24 h. Prevention measures aimed at protecting children’s respiratory health should consider the very acute effects of air pollution.
Display omitted
•Children’s respiratory infections are vulnerable to transient air pollution exposure.•We observed increased risk of upper and lower infections within few hours.•Greater risk of upper respiratory infections was seen in cold season and nigh-time.•Greater risk of lower respiratory infections was seen in warm season and daytime.
Children’s AURI and ALRI could happen within hours after exposure to particulate and gaseous air pollution.
Arbitrary-oriented object detection (AOOD) is a challenging task to detect objects in the wild with arbitrary orientations and cluttered arrangements. Existing approaches are mainly based on ...anchor-based boxes or dense points, which rely on complicated hand-designed processing steps and inductive bias, such as anchor generation, transformation, and non-maximum suppression reasoning. Recently, the emerging transformer-based approaches view object detection as a direct set prediction problem that effectively removes the need for hand-designed components and inductive biases. In this paper, we propose an Arbitrary-Oriented Object DEtection TRansformer framework, termed AO2-DETR, which comprises three dedicated components. More precisely, an oriented proposal generation mechanism is proposed to explicitly generate oriented proposals, which provides better positional priors for pooling features to modulate the cross-attention in the transformer decoder. An adaptive oriented proposal refinement module is introduced to extract rotation-invariant region features and eliminate the misalignment between region features and objects. And a rotation-aware set matching loss is used to ensure the one-to-one matching process for direct set prediction without duplicate predictions. Our method considerably simplifies the overall pipeline and presents a new AOOD paradigm. Comprehensive experiments on several challenging datasets show that our method achieves superior performance on the AOOD task.
Coronavirus disease 2019 (COVID-19) causes severe community and nosocomial outbreaks. Comprehensive data for serial respiratory viral load and serum antibody responses from patients infected with ...severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not yet available. Nasopharyngeal and throat swabs are usually obtained for serial viral load monitoring of respiratory infections but gathering these specimens can cause discomfort for patients and put health-care workers at risk. We aimed to ascertain the serial respiratory viral load of SARS-CoV-2 in posterior oropharyngeal (deep throat) saliva samples from patients with COVID-19, and serum antibody responses.
We did a cohort study at two hospitals in Hong Kong. We included patients with laboratory-confirmed COVID-19. We obtained samples of blood, urine, posterior oropharyngeal saliva, and rectal swabs. Serial viral load was ascertained by reverse transcriptase quantitative PCR (RT-qPCR). Antibody levels against the SARS-CoV-2 internal nucleoprotein (NP) and surface spike protein receptor binding domain (RBD) were measured using EIA. Whole-genome sequencing was done to identify possible mutations arising during infection.
Between Jan 22, 2020, and Feb 12, 2020, 30 patients were screened for inclusion, of whom 23 were included (median age 62 years range 37–75). The median viral load in posterior oropharyngeal saliva or other respiratory specimens at presentation was 5·2 log10 copies per mL (IQR 4·1–7·0). Salivary viral load was highest during the first week after symptom onset and subsequently declined with time (slope −0·15, 95% CI −0·19 to −0·11; R2=0·71). In one patient, viral RNA was detected 25 days after symptom onset. Older age was correlated with higher viral load (Spearman's ρ=0·48, 95% CI 0·074–0·75; p=0·020). For 16 patients with serum samples available 14 days or longer after symptom onset, rates of seropositivity were 94% for anti-NP IgG (n=15), 88% for anti-NP IgM (n=14), 100% for anti-RBD IgG (n=16), and 94% for anti-RBD IgM (n=15). Anti-SARS-CoV-2-NP or anti-SARS-CoV-2-RBD IgG levels correlated with virus neutralisation titre (R2>0·9). No genome mutations were detected on serial samples.
Posterior oropharyngeal saliva samples are a non-invasive specimen more acceptable to patients and health-care workers. Unlike severe acute respiratory syndrome, patients with COVID-19 had the highest viral load near presentation, which could account for the fast-spreading nature of this epidemic. This finding emphasises the importance of stringent infection control and early use of potent antiviral agents, alone or in combination, for high-risk individuals. Serological assay can complement RT-qPCR for diagnosis.
Richard and Carol Yu, May Tam Mak Mei Yin, The Shaw Foundation Hong Kong, Michael Tong, Marina Lee, Government Consultancy Service, and Sanming Project of Medicine.
We prove the well‐posedness and smoothing properties of a distributed‐order time‐fractional diffusion equation with a singular density function in multiple space dimensions, which could model the ...ultraslow subdiffusion processes. We accordingly derive a finite element approximation to the problem and prove its optimal‐order error estimate. Numerical results are presented to support the mathematical and numerical analysis.
The ability to determine the electronic structure of catalysts during electrochemical reactions is highly important for identification of the active sites and the reaction mechanism. Here we ...successfully applied soft X-ray spectroscopy to follow in operando the valence and spin state of the Co ions in Li
Co
O
under oxygen evolution reaction (OER) conditions. We have observed that a substantial fraction of the Co ions undergo a voltage-dependent and time-dependent valence state transition from Co
to Co
accompanied by spontaneous delithiation, whereas the edge-shared Co-O network and spin state of the Co ions remain unchanged. Density functional theory calculations indicate that the highly oxidized Co
site, rather than the Co
site or the oxygen vacancy site, is mainly responsible for the high OER activity.
Amorphous materials have attracted increasing attention in diverse fields due to their unique properties, yet their controllable fabrications still remain great challenges. Here, we demonstrate a ...top-down strategy for the fabrications of amorphous oxides through the amorphization of hydroxides. The versatility of this strategy has been validated by the amorphizations of unitary, binary and ternary hydroxides. Detailed characterizations indicate that the amorphization process is realized by the variation of coordination environment during thermal treatment, where the M-OH octahedral structure in hydroxides evolves to M-O tetrahedral structure in amorphous oxides with the disappearance of the M-M coordination. The optimal amorphous oxide (FeCoSn(OH)
-300) exhibits superior oxygen evolution reaction (OER) activity in alkaline media, where the turnover frequency (TOF) value is 39.4 times higher than that of FeCoSn(OH)
. Moreover, the enhanced OER performance and the amorphization process are investigated with density functional theory (DFT) and molecule dynamics (MD) simulations. The reported top-down fabrication strategy for fabricating amorphous oxides, may further promote fundamental research into and practical applications of amorphous materials for catalysis.
Sulfamethoxazole (SMX), a typical sulfonamide antibiotic, has been widely detected in secondary wastewater effluents and surface waters. In this work we investigated the oxidative degradation of SMX ...by commonly used oxidants of chlorine, ozone and permanganate. Chlorine and ozone were shown to be more effective for the removal of SMX (0.05-5.0mg/L), as compared with permanganate. Higher pH enhanced the oxidation of SMX by ozone and permanganate, but decreased the removal by chlorine. Moreover, the ozonation of SMX was significantly influenced by the presence of humic acid (HA), which exhibited negligible influence on the oxidation by chlorine and permanganate. Fairly lower mineralization of SMX occurred during the oxidation reactions, with the highest dissolved organic carbon (DOC) removal of 13% (for ozone). By using LC-MS/MS, 7, 5 and 5 oxidation products were identified for chlorine, ozone and permanganate and possible transformation pathways were proposed. It was shown that different oxidants shared some common pathways, such as the cleavage of SN bond, the hydroxylation of the benzene ring, etc. On the other hand, each of the oxidants also exhibited exclusive degradation mechanisms, leading to the formation of different transformation products (TPs). This work may provide useful information for the selection of oxidants in water treatment processes.
Abstract
The state-of-the-art active HER catalysts in acid media (e.g., Pt) generally lose considerable catalytic performance in alkaline media mainly due to the additional water dissociation step. ...To address this issue, synergistic hybrid catalysts are always designed by coupling them with metal (hydro)oxides. However, such hybrid systems usually suffer from long reaction path, high cost and complex preparation methods. Here, we discover a single-phase HER catalyst, SrTi
0.7
Ru
0.3
O
3-δ
(STRO) perovskite oxide highlighted with an unusual super-exchange effect, which exhibits excellent HER performance in alkaline media via atomic-scale synergistic active centers. With insights from first-principles calculations, the intrinsically synergistic interplays between multiple active centers in STRO are uncovered to accurately catalyze different elementary steps of alkaline HER; namely, the Ti sites facilitates nearly-barrierless water dissociation, Ru sites function favorably for OH* desorption, and non-metal oxygen sites (i.e., oxygen vacancies/lattice oxygen) promotes optimal H* adsorption and H
2
desorption.
PDF
