The pathogenesis of UC relates to gut microbiota dysbiosis. We postulate that alterations in the viral community populating the intestinal mucosa play an important role in UC pathogenesis. This study ...aims to characterise the mucosal virome and their functions in health and UC.
Deep metagenomics sequencing of virus-like particle preparations and bacterial 16S rRNA sequencing were performed on the rectal mucosa of 167 subjects from three different geographical regions in China (UC=91; healthy controls=76). Virome and bacteriome alterations in UC mucosa were assessed and correlated with patient metadata. We applied partition around medoids clustering algorithm and classified mucosa viral communities into two clusters, referred to as mucosal virome metacommunities 1 and 2.
In UC, there was an expansion of mucosa viruses, particularly
bacteriophages, and a decrease in mucosa
diversity, richness and evenness compared with healthy controls. Altered mucosal virome correlated with intestinal inflammation. Interindividual dissimilarity between mucosal viromes was higher in UC than controls.
and
were more abundant in the mucosa of UC than controls. Compared with metacommunity 1, metacommunity 2 was predominated by UC subjects and displayed a significant loss of various viral species. Patients with UC showed substantial abrogation of diverse viral functions, whereas multiple viral functions, particularly functions of bacteriophages associated with host bacteria fitness and pathogenicity, were markedly enriched in UC mucosa. Intensive transkingdom correlations between mucosa viruses and bacteria were significantly depleted in UC.
We demonstrated for the first time that UC is characterised by substantial alterations of the mucosa virobiota with functional distortion. Enrichment of
bacteriophages, increased phage/bacteria virulence functions and loss of viral-bacterial correlations in the UC mucosa highlight that mucosal virome may play an important role in UC pathogenesis.
A copper/aluminum/copper sandwich clad sheet was fabricated by means of cold rolling process and heat treated with different temperature and time. The Al/Cu interface and its bond strength were ...investigated by SEM, TEM and peeling test. The results reveal that low temperature heat treatment can improve the morphology of Al/Cu interface and increase its bond strength. However high temperature and long time result in the formation of Al
2Cu intermetallic compound layer, which is detrimental to the bond strength, and moreover, small Al
2O
3 particles precipitate along the Al
2Cu and Al interface. When the interlayer along Al/Cu interface grows to a certain thickness, the effect of heat treatment temperature and time become weak. For the present study, the reasonable heat treatment may be 423
K and 20
h.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
•T4 treatment improves the corrosion fatigue strength.•Localized corrosion and cracked TBs compete for the fatigue crack initiation.•T4 treatment alleviates the corrosion attack and weakens the ...HE.•Cracking at TBs reduces the corrosion fatigue lifetimes of T4 samples.
In this work, the corrosion fatigue behaviors of an as-forged Mg-6.7%Zn-1.3%Y-0.6%Zr alloy before and after solid solution treatment (T4) in 3.5 wt% NaCl solution have been investigated and compared. S-N curves showed that the fatigue strength of as-forged samples corresponding to 5 × 106 cycles was 30 MPa, whereas the fatigue strength of T4 samples was 50 MPa. Fracture observations showed that for the as-forged samples, fatigue cracks mainly initiated at localized corrosion sites on sample surfaces. However, for the T4 samples, the crack initiation was respectively related to the localized corrosion and TB cracking at low and high stress amplitudes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Postprocedural infections by Mycobacterium abscessus complex are increasing worldwide, and the source and route of transmission are infrequently identified. Here the extension of a previous ...clustering of paediatric patients with surgical site infections due to a single strain of the subspecies M. massiliense is reported. The investigation was conducted at a 2200-bed teaching hospital in Taiwan and included microbial surveillance of the environment (water, air, equipment and supplies) and a case–control study. We performed molecular identification and typing of the isolates by a trilocus sequencing scheme, confirmed by multilocus sequencing typing and pulsed-field gel electrophoresis. We investigated 40 patients who developed postprocedure soft tissue or bloodstream infections by M. massiliense (TPE101) during a 3-year period. Thirty-eight patients were identified at hospital A, and one newborn and her mother were identified at hospital B (185 km from hospital A). A case–control study identified the association of invasive procedures (adjusted odds ratio, 9.13) and ultrasonography (adjusted odds ratio, 2.97) (both p <0.05) with acquiring the outbreak strain. Isolates from the cases and unopened bottles of ultrasound transmission gel were all of strain ST48 and indistinguishable or closely related by pulsed-field gel electrophoresis. After replacement of contaminated gel, no new cases were detected during 18 months' follow-up. This investigation identified the use of contaminated gel as the common source causing an outbreak on a larger scale than had been recognized. Our findings halted production by the manufacturer and prompted revision of hospital guidelines.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
AbstractFour shear-critical RC shear walls were tested under a tension-bending-shear load to replicate seismic behavior of the bottom shear wall in high-rise buildings. The axial tension ratio ranged ...from 0 to 0.5 and the aspect ratio was 1.06. The shear compression failure mode was observed for each specimen, characterized by the formation of an inclined crack at 45° and direct strut action. The shear displacement was a dominant deformation component throughout the loading history. When the axial tension force increased from 0 to 1,293 kN, the ultimate drift ratio increased from 0.90% to 2.38%, while shear capacity linearly decreased from 1,507 to 895 kN. The load–displacement curve showed a significant pinching effect and strength degradation effect. In addition, this paper reports an innovative experimental method to obtain shear resistance of transverse reinforcement (Vs) based on the plasticity theory and strain measuring result. Test results using this method show that not all horizontal distributed rebar yield simultaneously at the ultimate capacity. The US code-specified shear strength contribution of horizontal distributed rebar was found to be unsafe for each test specimen. Finally, a database of RC shear walls subject to combined tension-bending-shear load was established to evaluate shear strength formulas in design codes. The comparison showed the Chinese code predicted spuriously higher tension-shear capacity, while the US code predicted conservative capacity. Based on the developed database, a simplified design formula is proposed with adequate safety concerns and accuracy.
Throat auroras have been suggested to correspond to magnetopause indentations, but how such indentations can be generated is an open question. Using coordinated magnetopause in situ and ...two‐dimensional auroral imaging observations, we showed that a transient magnetopause crossing observed by Time History of Events and Macroscale Interactions during Substorms near the dayside magnetopause corresponds to a throat aurora observed by Defense Meteorological Satellite Program/Special Sensor Ultraviolet Spectrographic Imager. The magnetopause crossing was confirmed to present a localized magnetopause indentation rather than arise from motion of the whole magnetopause. Using the minimum variance analysis and Walén test methods, we captured clear reconnection signatures at either boundary of the indentation. Also, an upstream solar wind discontinuity and a magnetosheath variation were identified to correlate well with the magnetopause indentation occurrence. These observations suggest that the magnetopause indentation was generated by reconnection and lend solid support to an assumption that throat aurora is produced by a particular reconnection that can develop inward the magnetosphere at a much‐localized region.
Plain Language Summary
The equatorward boundary of the discrete auroral oval near magnetic local noon is generally regarded as the open‐close field line boundary, which corresponds to the roughly smooth magnetopause boundary. Throat auroras are some north‐south aligned discrete auroral arcs attached at the equatorward edge of discrete auroral oval near local noon. Therefore, the throat auroras have been suggested to correspond to magnetopause indentations. However, no in situ observations show the existence of such indentations and how the indentations can be generated is also an open question. Taking advantage of coordinated Time History of Events and Macroscale Interactions during Substorms and Defense Meteorological Satellite Program/Special Sensor Ultraviolet Spectrographic Imager observations, we provided multipoint in situ observations, confirming that a transient magnetopause crossing correspondent to a typical throat aurora event was a magnetopause indentation. Also, with these observations, we captured clear reconnection signatures at either boundary of the indentation. Combined with the two‐dimensional morphology of the throat aurora, such magnetopause reconnection signatures may imply that during the generation of the throat aurora there exist an inwardly u‐shaped X line along the magnetopause indentation boundary.
Key Points
A localized magnetopause indentation correspondent to throat aurora is confirmed by multipoint in situ observations for the first time
Reconnection signatures at either boundary of the magnetopause indentation are captured by in situ observations for the first time
An upstream solar wind discontinuity is identified to be correlated with the occurrence of throat aurora for the first time
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Conducting polydimethylsiloxane (PDMS) composites are synthesized by mixing conductive nano‐ or microparticles witha PDMS gel. Experiments show that such composites exhibit good electrical ...conductivity and mechanical reliability, as well as desirable thermal characteristics. 3D microstructures, such as for the use of bio‐microchips, can be realized by a simple lithographic technique and a realistic 3D application is demonstrated (see figure).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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