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Summary
There is an increasing recognition of ethnic dermatology to reflect the increase in skin of colour (SOC) populations in the UK. ...Hyperpigmentary disorder is one of the commonest skin concerns in SOC but there has been limited training available in this field of dermatology. Variations in skin colour are genetically determined by the amount of melanin content, the eumelanin/pheomelanin ratio and the size of melanosomes, but is also influenced by other factors such as hormones and extrinsic factors such as ultraviolet radiation. Hyperpigmentation is a broad term to describe increased pigmentation in the skin, and making a correct diagnosis is an important first step in the successful management of hyperpigmentary disorders. A systematic approach based on the disease pathogenesis (e.g. reactive vs. nonreactive, increased melanin vs. increased number of cells or epidermal vs. dermal pigmentation) aided by a detailed history and clinical examination is the best way to diagnose a hyperpigmentary disorder. Based on its pathogenesis, management can be planned. For epidermal hyperpigmentation caused by increased melanin, topical skin‐lightening agents targeting inhibition of tyrosinase or melanosome transfer and promotion of keratinocyte turnover can be used. Hydroquinone‐containing cream is the gold‐standard treatment for epidermal hyperpigmentation. Alternative treatments include laser toning or chemical peels. However, increased dermal pigmentation is more challenging to target with topical treatments. If hyperpigmentation is due to increased numbers of melanocytes or keratinocytes, high‐fluence laser is the most appropriate treatment method.
Summary
Background
Rifaximin might decrease the risk of portal hypertension‐related complications by controlling small intestinal bacterial overgrowth.
Aim
To evaluate whether rifaximin was ...associated with the risk of death and cirrhotic complications.
Methods
We conducted a retrospective study that included 1042 patients experiencing hepatic encephalopathy (HE): 421 patients without hepatocellular carcinoma (HCC; the non‐HCC cohort) and 621 patients with HCC (the HCC cohort). The primary endpoint was overall survival and secondary endpoints were recurrence of HE and the development of spontaneous bacterial peritonitis (SBP), hepatorenal syndrome (HRS) and variceal bleeding.
Results
In the non‐HCC cohort, 145 patients received rifaximin plus lactulose (the rifaximin group) and 276 patients received lactulose alone (the control group). The multivariate analysis revealed that rifaximin was significantly associated with lower risk of death (adjusted hazard ratio aHR, 0.697; P = .024) and reduced the risk of recurrent HE (aHR, 0.452; P < .001), SBP (aHR, 0.210; P < .001) and variceal bleeding (aHR, 0.425; P = .011) but not HRS (aHR, 0.598; P = .08). In the HCC cohort, 173 patients received rifaximin plus lactulose and 448 patients received lactulose. Rifaximin was not associated with the risk of death (aHR, 1.177; P = .121). Rifaximin was associated with lower risk of SBP (aHR, 0.323; P < .001) but not with variceal bleeding (aHR, 0.660; P = .104) or recurrent HE (aHR, 0.689; P = .057). The risk of Clostridium difficile‐associated diarrhoea was not different between the groups (aHR, 0.028; P = .338).
Conclusions
In patients without HCC, rifaximin treatment was significantly associated with prolonged overall survival and reduced risks of spontaneous bacterial peritonitis, variceal bleeding and recurrent hepatic encephalopathy.
Linked Content
This article is linked to Juang, Kang et al, Wang et al, and Borentain et al papers. To view these papers visit https://doi.org/10.1111/apt.14325, https://doi.org/10.1111/apt.14343, https://doi.org/10.1111/apt.14353 and https://doi.org/10.1111/apt.14516.
Abstract An effective method for the 3D porous scaffold design of human tissue is presented based on a hybrid method of distance field and triply periodic minimal surface (TPMS). By the creative ...application of traditional distance field algorithm into the Boolean operations of the anatomical model and TPMS-based unit cell library, an almost defects free porous scaffolds having the complicated micro-structure and high quality external surface faithful to a specific anatomic model can be easily obtained without the difficult and time-consuming trimming and re-meshing processes. After generating the distance fields for the given tissue model and required internal micro-structure, a series of simple modifications in distance fields enable us to obtain a complex porous scaffold. Experimental results show that the proposed scaffold design method has the potential to combine the perfectly interconnected pore networks based on the TPMS unit cell libraries and the given external geometry in a consistent framework irrespective of the complexity of the models.
This paper reviews advanced optical burst switching (OBS) and optical packet switching (OPS) technologies and discusses their roles in the future photonic Internet. Discussions include optoelectronic ...and optical systems technologies as well as systems integration into viable network elements (OBS and OPS routers). Optical label switching (OLS) offers a unified multiple-service platform with effective and agile utilization of the available optical bandwidth in support of voice, data, and multimedia services on the Internet Protocol. In particular, OLS routers with wavelength routing switching fabrics and parallel optical labeling allow forwarding of asynchronously arriving variable-length packets, bursts, and circuits. By exploiting contention resolution in wavelength, time, and space domains, the OLS routers can achieve high throughput without resorting to a store-and-forward method associated with large buffer requirements. Testbed demonstrations employing OLS edge routers show high-performance networking in support of multimedia and data communications applications over the photonic Internet with optical packets and bursts switched directly at the optical layer
The spatiotemporal variations of surface air pollutants (O3, NO2, SO2, CO, and PM10) with four land-use types, residence (R), commerce (C), industry (I) and greenbelt (G), have been investigated at ...283 stations in South Korea during 2002-2013, using routinely observed data. The volatile organic compound (VOC) data at nine photochemical pollutant monitoring stations available since 2007 were utilized in order to examine their effect on the ozone chemistry. The land-use types, set by the Korean government, were generally consistent with the satellite-derived land covers and with the previous result showing anti-correlation between O3 and NO2 in diverse urban areas. The relationship between the two pollutants in the Seoul Metropolitan Area (SMA) residence land-use areas was substantially different from that outside of the SMA, probably due to the local differences in vehicle emissions. The highest concentrations of air pollutants in the diurnal, weekly, and annual cycles were found in industry for SO2 and PMPM10, in commerce for NO2 and CO, and in greenbelt for O3. The concentrations of air pollutants, except for O3, were generally higher in big cities during weekdays, while O3 showed its peak in suburban areas or small cities during weekends. The weekly cycle and trends of O3 were significantly out of phase with those of NO2, particularly in the residential and commercial areas, suggesting that vehicle emission was a major source in those areas. The ratios of VOCs to NO2 for each of the land-use types were in the order of I (10.2) > C (8.7) > G (3.9) > R (3.6), suggesting that most areas in South Korea were likely to be VOC-limited for ozone chemistry. The pollutants (NO2, SO2, CO, and PMPM10 except for O3 have decreased, most likely due to the effective government control. The total oxidant values (OX = O3 + NO2) with the land-use types were analyzed for the local and regional (or background) contributions of O3, respectively, and the order of OX (ppb) was C (57.4) > R (53.6) > I (50.7) > G (45.4), indicating the greenbelt observation was close to the background.
This Tutorial will discuss the motivation, benefits, and challenges of photonic switching in data centers and cover prospects of future data centers involving emerging new technologies and ...cross-layer solutions. The primary motivation for considering photonic switching in data centers rises from the need for energy-efficient and scalable intra-data center networks to meet rapid increases in data traffic driven by emerging applications, including machine learning. The data traffic inside the data centers (East-West traffic) is typically significantly greater than that of the traffic coming in and out of the data centers (North-South traffic) (Benson et al. 2010). To accommodate such traffic, today's large-scale data centers employ cascaded stages of many power-hungry electronic packet switches interconnected across the data center network in fixed hierarchical communication topologies. These electronic switches add significant latency and energy consumption while limiting the communication bandwidth. On the other hand, photonic switches can, in principle, support interconnections at very high data rates on many parallel wavelengths while keeping their energy consumption nearly independent of the switch port bandwidth. Numerous research papers have predicted significant benefits in scalability, throughput, and power efficiency from deploying photonic switches in data centers. However, photonic switching is not yet widely deployed in commercial warehouse-scale data centers at the time of writing this Tutorial due to significant challenges. They are related to 1) cross-layer issues involving control and management planes together with data integrity during switching, 2) scalability to >5000 racks (>a quarter-million servers), 3) performance monitoring required for reliable operation, 4) currently existing standards allowing limited power margin (3 dB), and 5) other practical (technology-dependent) issues relating to polarization sensitivity, temperature sensitivity, cost, etc. In telecom, commercial deployments of reconfigurable optical add-drop multiplexers (ROADMs) (Lightwave, 2003)-(Perrin, 2015) also had faced similar challenges and took place nearly ten years after the first research network testbed demonstrations in 1997 (Garrett, 2015) with fully implemented network control and management planes. In data centers, the challenges are far more significant due to the scale of the network and the dynamicity of the traffic. We will discuss possible solutions for future data centers involving cross-layer methods, new topologies, and innovative photonic switching technologies. In particular, the Tutorial broadly surveys state-of-the-art photonic switching technologies, architectures, and experimental results, and further covers the details of arrayed-waveguide-grating-router-based switch fabrics offering hybrid switching methods with distributed control planes towards scalable data center networking.
The human body characteristics as a signal transmission medium are studied for the application to intrabody communication. The measurements of the body channel cover the frequency range from 100 kHz ...to 150 MHz and the distance on the body up to 1.2 m. A distributed RC model is developed to analyze the large variation of the channel properties according to the frequency and channel length. The simulation results using the channel model match well with the measurements in both the frequency and time domains. The effect of the ground plane to the body channel transceivers is also investigated and an empirical formula for the minimum ground size is obtained. Finally, the amount of the electromagnetic radiation due to the body antenna effect is measured. With regards to the Federal Communications Commission regulations, the proper frequency range for the intrabody communication is determined to satisfy given bit error rate requirements
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Bioengineering of a functional cardiac tissue composed of primary cardiomyocytes has great potential for myocardial regeneration and in vitro tissue modeling. However, its ...applications remain limited because the cardiac tissue is a highly organized structure with unique physiologic, biomechanical, and electrical properties. In this study, we undertook a proof-of-concept study to develop a contractile cardiac tissue with cellular organization, uniformity, and scalability by using three-dimensional (3D) bioprinting strategy. Primary cardiomyocytes were isolated from infant rat hearts and suspended in a fibrin-based bioink to determine the priting capability for cardiac tissue engineering. This cell-laden hydrogel was sequentially printed with a sacrificial hydrogel and a supporting polymeric frame through a 300-µm nozzle by pressured air. Bioprinted cardiac tissue constructs had a spontaneous synchronous contraction in culture, implying in vitro cardiac tissue development and maturation. Progressive cardiac tissue development was confirmed by immunostaining for α-actinin and connexin 43, indicating that cardiac tissues were formed with uniformly aligned, dense, and electromechanically coupled cardiac cells. These constructs exhibited physiologic responses to known cardiac drugs regarding beating frequency and contraction forces. In addition, Notch signaling blockade significantly accelerated development and maturation of bioprinted cardiac tissues. Our results demonstrated the feasibility of bioprinting functional cardiac tissues that could be used for tissue engineering applications and pharmaceutical purposes.
Cardiovascular disease remains a leading cause of death in the United States and a major health-care burden. Myocardial infarction (MI) is a main cause of death in cardiovascular diseases. MI occurs as a consequence of sudden blocking of blood vessels supplying the heart. When occlusions in the coronary arteries occur, an immediate decrease in nutrient and oxygen supply to the cardiac muscle, resulting in permanent cardiac cell death. Eventually, scar tissue formed in the damaged cardiac muscle that cannot conduct electrical or mechanical stimuli thus leading to a reduction in the pumping efficiency of the heart. The therapeutic options available for end-stage heart failure is to undergo heart transplantation or the use of mechanical ventricular assist devices (VADs). However, many patients die while being on a waiting list, due to the organ shortage and limitation of VADs, such as surgical complications, infection, thrombogenesis, and failure of the electrical motor and hemolysis.
Ultimately, 3D bioprinting strategy aims to create clinically applicable tissue constructs that can be immediately implanted in the body. To date, the focus on replicating complex and heterogeneous tissue constructs continues to increase as 3D bioprinting technologies advance. In this study, we demonstrated the feasibility of 3D bioprinting strategy to bioengineer the functional cardiac tissue that possesses a highly organized structure with unique physiological and biomechanical properties similar to native cardiac tissue. This bioprinting strategy has great potential to precisely generate functional cardiac tissues for use in pharmaceutical and regenerative medicine applications.
Background
A virtual reality (VR) tour of the operating theatre before anaesthesia could provide a realistic experience for children. This study was designed to determine whether a preoperative VR ...tour could reduce preoperative anxiety in children.
Methods
Children scheduled for elective surgery under general anaesthesia were randomized into a control or VR group. The control group received conventional information regarding anaesthesia and surgery. The VR group watched a 4‐min video showing Pororo, the famous little penguin, visiting the operating theatre and explaining what is in it. The main outcome was preoperative anxiety, assessed using the modified Yale Preoperative Anxiety Scale (m‐YPAS) before entering the operating theatre. Secondary outcomes included induction compliance checklist (ICC) and procedural behaviour rating scale (PBRS) scores during anaesthesia.
Results
A total of 69 children were included in the analysis, 35 in the control group and 34 in the VR group. Demographic data and induction time were similar in the two groups. Children in the VR group had a significantly lower m‐YPAS score than those in the control group (median 31·7 (i.q.r. 23·3–37·9) and 51·7 (28·3–63·3) respectively; P < 0·001). During anaesthesia, the VR group had lower ICC and PBRS scores than the control group.
Conclusion
This preoperative VR tour of the operating theatre was effective in alleviating preoperative anxiety and increasing compliance during induction of anaesthesia in children undergoing elective surgery. Registration number: UMIN000025232 (http://www.umin.ac.jp/ctr).
Reduces anxiety
Electroreduction of small molecules such as H2O, CO2, and N2 for producing clean fuels or valuable chemicals provides a sustainable approach to meet the increasing global energy demands and to ...alleviate the concern on climate change resulting from fossil fuel consumption. On the path to implement this purpose, however, several scientific hurdles remain, one of which is the low energy efficiency due to the sluggish kinetics of the paired oxygen evolution reaction (OER). In response, it is highly desirable to synthesize high‐performance and cost‐effective OER electrocatalysts. Recent advances have witnessed surface reconstruction engineering as a salient tool to significantly improve the catalytic performance of OER electrocatalysts. In this review, recent progress on the reconstructed OER electrocatalysts and future opportunities are discussed. A brief introduction of the fundamentals of OER and the experimental approaches for generating and characterizing the reconstructed active sites in OER nanocatalysts are given first, followed by an expanded discussion of recent advances on the reconstructed OER electrocatalysts with improved activities, with a particular emphasis on understanding the correlation between surface dynamics and activities. Finally, a prospect for clean future energy communities harnessing surface reconstruction‐promoted electrochemical water oxidation will be provided.
During water splitting, the water oxidation condition reconstructs the electrocatalyst surface and concurrently enhances the performance and durability. To address the surface dynamics of the electrocatalyst and importance of reconstruction process under oxygen evolution reaction (OER) condition, in this review, the fundamentals of OER, origin of surface reconstruction, and comprehensive discussion on the experimental approaches for the electrocatalyst surface reconstruction are presented.
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