Pseudomonas aeruginosa is one of the most common pathogens isolated from respiratory tract specimen in patients with bronchiectasis. It is considered highly responsible for pathogenicity, progression ...and clinical outcomes of bronchiectasis.
To summarize existing evidence on how different factors of Pseudomonas aeruginosa affect the pathogenicity, progression and clinical outcomes of bronchiectasis, so as to provide possible insights for clinical practice and related research in the future.
PubMed was searched for studies pertaining to bronchiectasis and P. aeruginosa published to date, with no specific inclusion or exclusion criteria. Reference lists of retrieved reviews were searched for additional articles.
This review focused on non–cystic fibrosis bronchiectasis and also provided some data on cystic fibrosis when studies in bronchiectasis were limited. We discussed various factors in relation to P. aeruginosa: virulence factors, drug resistance, regulatory systems, genomic diversity and transmission of P. aeruginosa, as well as treatment for P. aeruginosa. Their impacts on bronchiectasis and its management were discussed.
The impact of P. aeruginosa on bronchiectasis is definite, although conclusions in some aspects are still vague. Faced with the worrying drug-resistance status and treatment bottleneck, individualized management and novel therapies beyond the classic pathway are most likely to be a future trend. To confirm the independent or integrated impact of various factors of P. aeruginosa on bronchiectasis and to figure out all the problems mentioned, larger randomized control trials are truly needed in the future.
Abstract
This paper studies the feasibility of replacing damaged deck of posttensioned concrete box-girder bridges without the use of falsework to support the superstructure span. Parameters of the ...study included straight, curved, and skewed bridges, and simple versus multispan bridges. Deck replacement in posttensioned box-girder bridges requires special attention because the deck forms an integral part of the load-resisting mechanism and large precompression has been locked in by the posttensioning in the superstructure. The potential unfavorable stress reversals or redistribution during deck replacement should be carefully considered. In this study, practical options for lane closure and traffic rerouting were incorporated into the replacement strategies, and these options included temporal longitudinal and transverse replacements. Additionally, time-dependent properties for concrete and steel representatives of current construction practice were included in the finite-element model. Results indicated that full-depth deck replacement may be difficult and undesirable because the current AASHTO stress limits were violated in all four of the posttensioned box-girder bridges selected for the study. Additionally, the increase in permanent deflections through deck replacement was relatively large for these selected bridges, which is likely to result in degraded ride quality, safety, and poor drainage condition for the bridge. As a general trend, critical stresses at the top of the web and downward deflection of the girders were found to accumulate as the deteriorated deck was removed and a new deck cast.
Thin polymer films have striking dynamical properties that differ from their bulk counterparts. With the simple geometry of a stepped polymer film on a substrate, we probe mobility above and below ...the glass transition temperature Tg. Above Tg the entire film flows, whereas below Tg only the near-surface region responds to the excess interfacial energy. An analytical thin-film model for flow limited to the free surface region shows excellent agreement with sub-Tg data. The system transitions from whole-film flow to surface localized flow over a narrow temperature region near the bulk Tg. The experiments and model provide a measure of surface mobility in a simple geometry where confinement and substrate effects are negligible. This fine control of the glassy rheology is of key interest to nanolithography among numerous other applications.
The SARS-CoV-2 Omicron variant has demonstrated enhanced transmissibility and escape of vaccine-derived immunity. Although first-generation vaccines remain effective against severe disease and death, ...robust evidence on vaccine effectiveness (VE) against all Omicron infections, irrespective of symptoms, remains sparse. We used a community-wide serosurvey with 5,310 subjects to estimate how vaccination histories modulated risk of infection in infection-naive Hong Kong during a large wave of Omicron BA.2 epidemic in January-July 2022. We estimated that Omicron infected 45% (41-48%) of the local population. Three and four doses of BNT162b2 or CoronaVac were effective against Omicron infection 7 days after vaccination (VE of 48% (95% credible interval 34-64%) and 69% (46-98%) for three and four doses of BNT162b2, respectively; VE of 30% (1-66%) and 56% (6-97%) for three and four doses of CoronaVac, respectively). At 100 days after immunization, VE waned to 26% (7-41%) and 35% (10-71%) for three and four doses of BNT162b2, and to 6% (0-29%) and 11% (0-54%) for three and four doses of CoronaVac. The rapid waning of VE against infection conferred by first-generation vaccines and an increasingly complex viral evolutionary landscape highlight the necessity for rapidly deploying updated vaccines followed by vigilant monitoring of VE.
The specific aim of this study was to gain insight into the influence of scaffold pore size, pore shape and permeability on the in vitro proliferation and differentiation of three-dimensional (3-D) ...human periosteum-derived cell (hPDC) cultures. Selective laser melting (SLM) was used to produce six distinct designed geometries of Ti6Al4V scaffolds in three different pore shapes (triangular, hexagonal and rectangular) and two different pore sizes (500μm and 1000μm). All scaffolds were characterized by means of two-dimensional optical microscopy, 3-D microfocus X-ray computed tomography (micro-CT) image analysis, mechanical compression testing and computational fluid dynamical analysis. The results showed that SLM was capable of producing Ti6Al4V scaffolds with a broad range of morphological and mechanical properties. The in vitro study showed that scaffolds with a lower permeability gave rise to a significantly higher number of cells attached to the scaffolds after seeding. Qualitative analysis by means of live/dead staining and scanning electron micrography showed a circular cell growth pattern which was independent of the pore size and shape. This resulted in pore occlusion which was found to be the highest on scaffolds with 500μm hexagonal pores. Interestingly, pore size but not pore shape was found to significantly influence the growth of hPDC on the scaffolds, whereas the differentiation of hPDC was dependent on both pore shape and pore size. The results showed that, for SLM-produced Ti6Al4V scaffolds with specific morphological and mechanical properties, a functional graded scaffold will contribute to enhanced cell seeding and at the same time can maintain nutrient transport throughout the whole scaffold during in vitro culturing by avoiding pore occlusion.
Stem cells are remarkable, and stem cell–based tissue engineering is an emerging field of biomedical science aiming to restore damaged tissue or organs. In dentistry and reconstructive facial ...surgery, it is of great interest to restore lost teeth or craniofacial bone defects using stem cell–mediated therapy. In the craniofacial region, various stem cell populations have been identified with regeneration potential. In this review, we provide an overview of the current knowledge concerning the various types of tooth- and craniofacial bone–related stem cells and discuss their in vivo identities and regulating mechanisms.
A Josephson radiation threshold detector (JRTD) that is based on the threshold behaviour of a current bias Josephson junction (CBJJ) is designed and fabricated for infrared radiation (IR@1550nm) ...detection at low temperatures. To achieve the optimal performance, we develop a binary hypothesis detection method to calibrate Josephson threshold behaviours (i.e. the switching current distributions of the CBJJ with the Al/AlO
/Al junction) in the absence and presence of radiation. In the absence of IR radiation, the junction transitioned with a measurable voltage drop across the junction, and this signal was treated as the events of hypothesis H
. The events of junction transition observed in the presence of the IR radiation served as hypothesis H
. Considering the usual Gaussian noise and based on statistical decision theory, the accumulated data of the measured switching current distributions are processed, and the threshold sensitivity of the demonstrated JRTD device is estimated. The minimum detectable IR radiation power of the proposed detector is approximately 0.74 pW, which corresponds to the photon rate of 5.692 × 10
photons/second. Further optimisation of JRTDs to implement the desired binary detection of a single photon is still a subject of argument, at least theoretically.
Self-accommodation morphology of the
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martensites in Ti–Nb shape memory alloys with Nb content ranging from 20 to 24 at.% was investigated. Hollow and solid triangular morphologies consisting of ...three
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variants were found to be the
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self-accommodation morphologies. The
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variants are related to each other by twinning on
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. A V-shaped morphology consisting of two
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variants coupled with a solid triangular morphology consisting of three
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variants was found to be another type of self-accommodation morphology. The
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variants from the V-shaped morphology are related by twinning on
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}
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, whereas the
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variants from the solid triangular morphology are related to each other by twinning on
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. Pairs of crystallographically equivalent
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twinning dislocations with steps of opposite signs were found to cause the overall orientation of the twinning terraces and steps to be parallel to the
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twinning interface.
The 2010/2011 Canterbury earthquakes in New Zealand revealed: 1) Improved structural response resulting from historical design advancements; 2) Poor structural performance due to previously ...identified shortcomings being insufficiently addressed in design practice; and 3) New deficiencies that were not previously recognized because of premature failure resulting from other design flaws. This paper summarizes damage to concrete walls observed in the February 2011 Christchurch earthquake, proposes links between the observed response and specific design concerns, and offers suggestions for improving seismic design of walls in the following areas: amount of longitudinal reinforcement in wall end regions, suitable wall thickness to minimize the potential for out-of-plane buckling, and minimum vertical reinforcement requirements.
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