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Objectives We determined the common clinical characteristics of patients infected with Helicobacter pylori (H. pylori) and investigated the relationship between H. pylori infection, and clinical symptoms, and gastroscopic manifestations. Our focus was specifically on the clinical manifestations in asymptomatic patients. Methods We obtained the physical examination data of patients who underwent the 14C urea breath test between January 2018 and December 2020 at our Hospital. Basic demographic data, questionnaire data on clinical symptoms, and clinical examination data of the patients were also collected, and the correlation analysis was performed. Results A total of 2863 participants were included in the study. The overall H. pylori infection rate was 26.30%. The clinical symptoms between H. pylori -positive patients and H. pylori- negative patients did not differ significantly (P  > .05). However, H. pylori -positive patients exhibited more severe gastroscopic manifestations (P  < .001). The 14C urea breath test disintegrations per minute (DPM) values in H. pylori -positive patients correlated with their serum pepsinogen and gastrin-17 levels. With an increase in the DPM value, more combinations of clinical symptoms appeared in the patients. Among H. pylori -positive patients, DPM levels in asymptomatic patients were lower than those in symptomatic patients (P  < .001). However, gastroscopic manifestations did not vary significantly between asymptomatic and symptomatic patients (P  > .05). Conclusion Patients infected with H. pylori showed no specific gastrointestinal symptoms. Patients with asymptomatic infection showed lower DPM levels, but their gastroscopic manifestations were similar to those of patients with symptomatic infection, and their lesions were more severe than H. pylori -negative people. Key message What is already known on the subject H. pylori is highly contagious and is an important etiological factor for many kinds of disease. Eradication of H. pylori infection can decrease the cost of prevention, diagnosis, and treatment of H. pylori -associated diseases, but the eradication therapy may lead to adverse drug reactions. It has been suggested the treatment for asymptomatic infections should not overkill. What we have found Gastroscopic manifestations of asymptomatic patients were similar to those of symptomatic patients. Both of their lesions were more severe than H. pylori -negative individuals. We provide a theoretical basis for the consideration of the need for further gastroscopy and treatment in clinically asymptomatic infected patients. [ABSTRACT FROM AUTHOR]

The basic principles and methods of infrared radiation and infrared stealth technology were discussed in this paper. It was found that flexible regulation of multi-band spectrum was the key to realize infrared stealth compatible with radar stealth, laser stealth and visible light stealth. The research status of traditional infrared stealth materials were summarized and the bottleneck of their development was clarified. Furthermore, the design idea, research basis and development advantages of infrared stealth metamaterials with spectral tailoring function were proposed. We reviewed the research status and development trend of the infrared stealth compatible with radar stealth, infrared stealth with infrared radiation window and infrared stealth compatible with laser and visible light.

We evaluate the factors influencing the abundance, [Li], and isotopic composition of riverine Li delivered to the oceans through analyses and modeling of [Li] and δ7Li in streams and groundwaters draining a single continental lithology, the Columbia River Basalts (CRBs). The streams were sampled in different climate zones that lie east (dry), and west (wet) of the Cascades Mountains, and during two different seasons (summer and late winter) in order to evaluate climatic and seasonal influences on Li isotopes in rivers. Dissolved Li (δLidis7=+9.3 to +30.4) is systematically heavier than that of fresh or weathered CRBs (-4.7 to +6.0, Liu et al., 2013), suspended loads (-5.9 to -0.3), and shallow groundwaters (+6.7 to +9.4), consistent with previous studies showing that Li isotope fractionation is affected by equilibration between stream water and secondary minerals. However, the lack of correlation between δ7Lidis and climate zone, the uniform secondary minerals and bedrock, coupled with the highly variable (>20‰) δLidis7 indicate that other factors exert a strong control on δ7Lidis. In particular, the heavier Li in streams compared to the shallow groundwaters that feed them indicates that continued isotopic fractionation between stream water and suspended and/or bed loads has a major influence on riverine δ7Li. Seasonal δ7Li variation is observed only for streams west of the Cascades, where the difference in precipitation rate between the dry and wet seasons is greatest. Reactive transport model simulations reveal that riverine δ7Li is strongly controlled by subsurface residence times and the Li isotope fractionation occurring within rivers. The latter explains why there is no positive correlation between δ7Li and traditional weathering proxies such as Si or normalized Si in rivers, as riverine Li isotope fractionation drives δ7Li to higher values during transport, whereas the concentrations of major cations and anions are diluted. The varying residence time for groundwaters feeding the western streams in summer (long residence times, higher δ7Li, greater weathering) and winter (short residence times, lower δ7Li, less weathering) explains the observed seasonal variations. A global, negative correlation between δ7Li and Li/Na for streams and rivers draining basaltic catchments reflects the overall transport time, hence the amount of silicate weathering. Based on our results, the increase of δ7Li in seawater during the Cenozoic is unlikely related to changing climate, but may reflect mountain building giving rise to increased silicate weathering.

This study aimed to explore the mechanism of naringin (Nar) in alleviating ultraviolet B (UVB)‐induced HaCaT cell senescence and damage. Human keratinocytes (HaCaT cells) were divided into control, UVB, UVB + Nar, UVB + Cap, and UVB + Nar + Cap groups. Analysis was performed using the MTT assay to assess cell viability, flow cytometry to measure the apoptosis level, SA‐β‐Gal staining to observe cellular senescence, and Western blot to assess protein levels of TRPV1, p16, p53, p21, matrix metalloproteinase (MMP)‐1, and MMP‐9. Both UVB irradiation and capsaicin (Cap) treatment upregulated the expression of TRPV1 in HaCaT cells, inhibited cell proliferation, promoted apoptosis, and increased the expression of p16, p53, p21, MMP‐1, and MMP‐9. Nar treatment reversed the above effects via inhibition of TRPV1 expression, thereby relieving senescence and cell damage induced by UVB irradiation. Taken together, these findings suggest that Nar can reduce UVB‐induced senescence and damage in HaCaT cells by acting as an antagonist of TRPV1. [ABSTRACT FROM AUTHOR]

Mineralogical, chemical, and Li and Nd isotopic compositions of two drill cores (8-9m deep) through bauxites developed on the Miocene Columbia River Basalts document the changes associated with basalt weathering, provide insights into the processes involved, and allow us to examine the overall influence of chemical weathering on juvenile (basaltic) crust. Gibbsite, hematite, ±kaolinite, halloysite, goethite, and maghemite are the weathering products in the bauxites. Quartz is observed near the tops of the cores and its abundance decreases progressively with depth; no quartz is observed below five meters depth in either core. Most major and trace elements, including "mobile" and some "immobile" elements are severely depleted in the bauxites. Niobium is less mobile relative to the rare earth elements, thus chemical weathering attenuates the negative Nb anomaly in the continental crust. Li and Nd are strongly depleted relative to fresh basalt, and both increase systematically towards the surface in the quartz-bearing samples while δ7Li and εNd values decrease systematically towards the surface in these same samples. Both Li and Nd were likely lost from the bauxites through leaching. The systematic enrichment of Li, Nd, and quartz, as well as the less radiogenic Nd isotopic composition at the tops of both profiles reflects 20-60wt.% addition of an eolian component to the soils. The eolian dust is unlikely to have experienced significant post-depositional weathering due to the relatively high Li contents near the tops of the profiles, and, therefore, the low δ7Li and εNd values suggest that the dust came from an old, weathered region of the continent. Our results demonstrate that lithium isotopes are sensitive tracers of chemical weathering, particularly in extreme weathering settings, and support the hypothesis that chemical weathering influences the mass and composition of the continental crust. © 2013 Elsevier Ltd.