The clinical features and immune responses of asymptomatic individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been well described. We studied 37 ...asymptomatic individuals in the Wanzhou District who were diagnosed with RT-PCR-confirmed SARS-CoV-2 infections but without any relevant clinical symptoms in the preceding 14 d and during hospitalization. Asymptomatic individuals were admitted to the government-designated Wanzhou People's Hospital for centralized isolation in accordance with policy
. The median duration of viral shedding in the asymptomatic group was 19 d (interquartile range (IQR), 15-26 d). The asymptomatic group had a significantly longer duration of viral shedding than the symptomatic group (log-rank P = 0.028). The virus-specific IgG levels in the asymptomatic group (median S/CO, 3.4; IQR, 1.6-10.7) were significantly lower (P = 0.005) relative to the symptomatic group (median S/CO, 20.5; IQR, 5.8-38.2) in the acute phase. Of asymptomatic individuals, 93.3% (28/30) and 81.1% (30/37) had reduction in IgG and neutralizing antibody levels, respectively, during the early convalescent phase, as compared to 96.8% (30/31) and 62.2% (23/37) of symptomatic patients. Forty percent of asymptomatic individuals became seronegative and 12.9% of the symptomatic group became negative for IgG in the early convalescent phase. In addition, asymptomatic individuals exhibited lower levels of 18 pro- and anti-inflammatory cytokines. These data suggest that asymptomatic individuals had a weaker immune response to SARS-CoV-2 infection. The reduction in IgG and neutralizing antibody levels in the early convalescent phase might have implications for immunity strategy and serological surveys.
We report acute antibody responses to SARS-CoV-2 in 285 patients with COVID-19. Within 19 days after symptom onset, 100% of patients tested positive for antiviral immunoglobulin-G (IgG). ...Seroconversion for IgG and IgM occurred simultaneously or sequentially. Both IgG and IgM titers plateaued within 6 days after seroconversion. Serological testing may be helpful for the diagnosis of suspected patients with negative RT-PCR results and for the identification of asymptomatic infections.
In the recent years, Mn4+‐doped phosphors for indoor plant cultivation have received extensive concern owing to the far‐red emission that can match well with the absorption spectra of plant pigments. ...Whereas, many Mn4+‐doped phosphors still face some challenges such as poor light efficiency and low thermal stability. It is an effective way to resolve these problems via cation vacancies engineering. Herein, the Ca14−xAl10Zn6−yO35: Mn4+ phosphors are successfully synthesized by combustion method. The luminescence intensity of Ca14−xAl10Zn6−yO35: Mn4+ phosphor is enhanced through engineering Ca2+ and Zn2+ vacancies according to the charge compensation mechanism. The optimal content of each Ca2+ and Zn2+ vacancy is equal to be 0.3. Furthermore, the defect formation is accompanied with lattice distortion, which plays a vital role in driving the excited phonon traps to reduce the energy loss by non‐radiation transitions. Therefore, the thermal stability of Ca14−xAl10Zn6−yO35: Mn4+ phosphor is also improved via engineering cation vacancies. In addition, the Ca14−xAl10Zn6−yO35: Mn4+ phosphors can be effectively excited by blue light and it exhibits far‐red emission due to the Mn4+ spin‐forbidden 2E → 4A2 transition. The results suggest that the Ca14−xAl10Zn6−yO35: Mn4+ phosphors can have a tremendous potential in indoor plant cultivation.
To understand the protective effect of NF-κB signaling pathway inhibitor pyrrolidinedithiocarbamate (PDTC) on mice with chronic atrophic gastritis (CAG).
Helicobacter pylori (H. pylori) infection ...combined with high-salt diet was used to construct the CAG mouse model, and 100 or 200 mg/kg/day PDTC was intragastrically treated for 8 weeks. Then, hematoxylin and eosin (HE) and Alcian blue-periodic acid-Schiff (AB-PAS) staining were used to observe the pathology of gastric mucosa, while immunohistochemistry, quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immuno sorbent assay (ELISA) and western blotting were determined to detect the expression of related molecules.
The nuclear content of NF-κB p65 in the gastric mucosa of the CAG mice was increased accompanying by the structural disorder of the gastric mucosal epithelium, inflammatory cell infiltration, intestinal metaplasia, and increased MUC2 expression, but the symptoms were alleviated after PDTC treatment. In addition, the expressions of TNF-α, IL-1β, IL-6 and COX2 in the gastric mucosa and serum of CAG mice were higher than those control mice, which were reduced in CAG mice treated with either 100 or 200 mg/kg PDTC. Furthermore, 100 mg/kg and 200 mg/kg PDTC treatments reduced the serum PGE
2
in CAG mice with the decreased PCNA and Ki-67 expression in gastric mucosa. The therapeutic effect of 200 mg/kg PDTC was significantly better than that of 100 mg/kg PDTC.
PDTC inhibited inflammation and the excessive proliferation of gastric mucosal epithelial cells, thereby exerting a potential therapeutic effect on CAG.
Plant growth LEDs have attracted broad attention in modern society, desperate for specific phosphors with a characteristic emission band. A novel Mn4+ and Dy3+ co-doped Y3Al4GaO12 phosphor were ...successfully prepared through a conventional high-temperature solid-state reaction. A three band emission including red (625–700 nm), orange (550–607 nm) and blue (462–490 nm) is observed in these phosphors when excited under a near-UV lamp, which is ascribed to 2E → 4A2 of Mn4+, 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 of Dy3+, respectively. The three emissions match the absorption spectra of chlorophyll A and chlorophyll B well. Meanwhile, the energy transfer from Dy3+ to Mn4+ was confirmed by the luminescence spectra and lifetime analysis. Finally, an LED device was fabricated that consisted of a 365 nm ultraviolet chip and the Y3Al4GaO12:Mn4+,Dy3+ phosphor. The excellent properties indicate that the synthesized phosphor has a promising application in the optical agricultural industry.
Combining spatial and temporal primitives together is quite useful to specify dynamic behaviors of cyber-physical systems. The ability to represent spatio-temporal properties by means of formulas in ...spatio-temporal logics has recently found important applications in various fields, such as runtime verification, parameter synthesis, and falsification. In this paper, we present a spatio-temporal specification language,
STSL
, by combining signal temporal logic (
STL
) with a spatial logic
S
4
u
to characterize spatio-temporal dynamic behaviors of cyber-physical systems. This language is highly expressive: it allows the description of quantitative signals, by expressing spatio-temporal traces over real-valued signals in dense time, and Boolean signals, by constraining values of spatial objects across threshold predicates.
STSL
combines the power of temporal modalities and spatial operators and enjoys important properties such as safety and liveness. We provide the falsification problem through extending Lemire’s algorithm and a parameter synthesis procedure by calling the simulated annealing algorithm. We demonstrate the proposed approach on the adaptive cruise control system and path planning of quadrotors.
Acute leukemia with ambiguous lineage (ALAL) is a rare and highly aggressive malignancy with limited molecular characterization and therapeutic recommendations. In this study, we retrospectively ...analyzed 1635 acute leukemia cases in our center from January 2012 to June 2018. The diagnose of ALAL was based on either EGIL or 2016 WHO criteria, a total of 39 patients were included. Four patients diagnosed as acute undifferentiated leukemia (AUL) by both classification systems. Among the patients underwent high-throughput sequencing, 89.5% were detected at least one mutation and the median number of gene mutation was 3 (0-8) per sample. The most frequently mutated genes were NRAS (4, 21%), CEBPA (4, 21%), JAK3 (3, 16%), RUNX1 (3, 16%). The mutations detected in mixed-phenotype acute leukemia (MPAL) enriched in genes related to genomic stability and transcriptional regulation; while AUL cases frequently mutated in genes involved in signaling pathway. The survival analysis strongly suggested that mutation burden may play important roles to predict the clinical outcomes of ALAL. In addition, the patients excluded by WHO criteria had even worse clinical outcome than those included. The association of the genetic complexity of blast cells with the clinical outcomes and rationality of the diagnostic criteria of WHO system need to be evaluated by more large-scale prospective clinical studies.
Non–rare earth Mn4+‐activated strontium aluminate phosphor is considered to be a promising material for plant cultivation field owing to their advantage of inexpensively, environment friendly, ...nontoxic, and appropriate spectral range. In this paper, a Sr4−xBaxAl13.99O25:0.01Mn4+,1.4H3BO3 strontium aluminate phosphor is synthesized by a convenient high‐temperature solid‐state reaction. The photoluminescence spectra located at red region with a peak at 655 nm in the range of 600 to 750 nm that can be excited under the excitation of ultraviolet (~346 nm) or blue light (~450 nm). The shape emission band at 655 nm is attributed to the transition of 2Eg‐4A2g. Furthermore, the emission intensity of Sr4−xBaxAl13.99O25: 0.01Mn4+,1.4H3BO3 phosphor is conducted in detail with the variety of Ba2+ doping concentration and the intensity can be enhanced to 140.9% than the Sr4Al13.99O25:0.01Mn4+,1.4H3BO3 when the value of Ba2+ concentration equal to 0.1 mol. In addition, the X‐ray diffraction spectra, element mapping, composition modifying, optical properties, FT‐IR spectra, diffuse reflectance spectra, thermal stability, and fluorescence lifetime are systematically investigated. According to the electro‐luminescent spectra of as‐packaged LED, indicating that the Sr3.9Ba0.1Al13.99O25:0.01Mn4+,1.4H3BO3 phosphor will become a great candidate for plant cultivation LEDs due to the emission spectra match well the plant pigment spectrum.
Black carbon (BC) is an essential climate forcer in the atmosphere. Large uncertainties remain in BC’s radiative forcing estimation by models, partially due to the limited measurements of BC vertical ...distributions near the surface layer. We conducted time-resolved vertical profiling of BC using a 356-m meteorological tower in Shenzhen, China. Five micro-aethalometers were deployed at different heights (2, 50, 100, 200, and 350 m) to explore the temporal dynamics of BC vertical profile in the highly urbanized areas. During the observation period (December 6–15, 2017), the average equivalent BC (eBC) concentrations were 6.6 ± 3.6, 5.4 ± 3.3, 5.9 ± 2.8, 5.2 ± 1.8, and 4.9 ± 1.4 μg m
−3
, from 2 to 350 m, respectively. eBC temporal variations at different heights were well correlated. eBC concentrations generally decreased with height. At all five heights, eBC diurnal variations exhibited a bimodal pattern, with peaks appearing at 09:00–10:00 and 19:00–21:00. The magnitudes of these diurnal peaks decreased with height, and the decrease was more pronounced for the evening peak. eBC episodes were largely initiated by low wind speeds, implying that wind speed played a key role in the observed eBC concentrations. eBC wind-rose analysis suggested that elevated eBC events at different heights originate from different directions, which suggested contributions from local primary emission plumes. Air masses from central China exhibited much higher eBC levels than the other three backward trajectory clusters found herein. The absorption Ångström exponent (AAE
375–880
) showed clear diurnal variations at 350 m and increased slightly with height.
This study aimed to help improve the diagnosis and treatment of isolated myeloid sarcoma. We report the case of a female adolescent patient with isolated meningeal myeloid sarcoma. She was admitted ...to our department because of vomiting, headache and hearing loss. Positron emission tomography-computed tomography and brain magnetic resonance imaging showed multiple intracranial space-occupying lesions. A complete examination, including morphology, cytology, immunophenotyping, cytogenetics and molecular biology tests of cerebrospinal fluid and bone marrow, was conducted. The diagnosis of primary myeloid sarcoma of the central nervous system with mixed lineage leukemia gene rearrangement with AF6 was established. The patient underwent systemic chemotherapy and intrathecal treatment followed by whole-brain radiotherapy. She achieved complete remission for 84 months and has not developed bone marrow involvement during follow-up. The combination of morphology, cytology, flow cytometry, cytogenetics and molecular analysis can improve the definite diagnosis of isolated myeloid sarcoma.
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