Search

The liver releases glucose into the blood using the glucose-6-phosphatase (G6Pase) system, a multiprotein complex located in the endoplasmic reticulum (ER). Here, we show for the first time that the G6Pase system is also expressed in hypothalamic tanycytes, and it is required to regulate energy balance. Using automatized qRT-PCR and immunohistochemical analyses, we evaluated the expression of the G6Pase system. Fluorescent glucose analogue (2-NBDG) uptake was evaluated by 4D live-cell microscopy. Glucose release was tested using a glucose detection kit and high-content live-cell analysis instrument, Incucyte s3. In vivo G6pt knockdown in tanycytes was performed by AAV 1 -shG6PT-mCherry intracerebroventricular injection. Body weight gain, adipose tissue weight, food intake, glucose metabolism, c-Fos, and neuropeptide expression were evaluated at 4 weeks post-transduction. Tanycytes sequester glucose-6-phosphate (G6P) into the ER through the G6Pase system and release glucose in hypoglycaemia via facilitative glucose transporters (GLUTs). Strikingly, in vivo tanycytic G6pt knockdown has a powerful peripheral anabolic effect observed through decreased body weight, white adipose tissue (WAT) tissue mass, and strong downregulation of lipogenesis genes. Selective deletion of G6pt in tanycytes also decreases food intake, c-Fos expression in the arcuate nucleus (ARC), and Npy mRNA expression in fasted mice. The tanycyte-associated G6Pase system is a central mechanism involved in controlling metabolism and energy balance. [Display omitted] • Tanycytes express the G6Pase system. • Tanycytes sequester G6P in the ER. • Tanycytes release glucose in hypoglycaemia through GLUTs. • Tanycytes-expressing G6Pase system regulate the energy balance. [ABSTRACT FROM AUTHOR]

[Display omitted] • We propose a procedure for indoor soiling studies by using spin coating technique. • Dust samples were collected from PV modules installed in the Atacama Desert. • Homogeneous dust deposition was obtained within 25 s using spin coating technique. • Physicochemical characteristics of material allowed understanding the cementation. • As dust amount increased, light attenuation in the UV range became more significant. Soiling affects the economic profitability of solar photovoltaic plants, reducing productivity of the photovoltaic modules and increasing maintenance costs. Typically, studies on the soiling impact on photovoltaic technologies conducted outdoors require long exposure times. This paper deals with a new methodology for accelerated indoor test. Dust samples from the Atacama Desert are used to study physicochemical aspects of local soiling and its effects in the performance of solar cells. The new methodology is based on spin-coating to deposit homogeneous soiling layers on photovoltaic glass. This technique allows different soil mixtures to be deposited, resulting in the desired surface dust densities. X-ray diffraction and scanning electron microscopy of samples with artificially indoor and naturally outdoor deposited dust revealed similar behavior. In both, gypsum was the soluble material supporting the cementation process. The external quantum efficiency of the solar cell under different soiling conditions allowed to evaluate its effect on the photogenerated current density (J ph) for different spectral ranges. As expected from other studies, the influence of soiling is higher in the ultraviolet spectral range than at other wavelengths. It is observed that as the amount of deposited soil increases, the J ph losses are higher in the ultraviolet spectral range than in the visible or infrared. Because of the reduction in current density, efficiency is affected as the surface dust density increases. For instance, the efficiency decreased by 66.5% for 1.37 mg/cm2. [ABSTRACT FROM AUTHOR]

Neural mobilization (NM) techniques have been shown to improve the neural tissue's viscoelastic properties that may lead to recover of the function of the nerve after lumbar spine surgery. This study aimed to determine the effects of NM in addition to standard rehabilitation on lumbar and sciatic pain intensity, disability level, and quality of life in patients after receiving a microdiscectomy of the intervertebral lumbar disc (IVD). Twenty-four participants (age 41.3 ± 8.3 years old) within 3–4 weeks of a microdiscectomy of an IVD were randomly allocated to control (CTRL; n = 12) or NM group (n = 12). The CTRL group received ten standard rehabilitation sessions. The NM group received the same rehabilitation sessions with the addition of NM techniques. The intensity of lumbar and sciatic pain (visual analogue scale), disability level (Oswestry disability index), and health-related quality of life (SF-36 questionnaire) were measured before and after the intervention. Within-group analysis revealed a significant reduction in lumbar (p < 0.05) and sciatic pain intensity (p < 0.001), disability level (p < 0.001), and improvement in the physical function and problems, vitality, emotional well-being, and pain SF-36 items (p < 0.05) in both groups. There were no statistical differences between groups in all outcomes. A standard rehabilitation protocol alone or in combination with NM techniques are equally effective in reducing pain and disability level, as well as improving quality of life in patients after a microdiscectomy due to intervertebral lumbar disc lesion. • Rehabilitation alone or in combination with NM decreased pain and disability in patients after a microdiscectomy. • Rehabilitation alone or in combination with NM improved quality of life in patients after a microdiscectomy. • The NM techniques do not induce further beneficial effects to standard rehabilitation in patients after a microdiscectomy. [ABSTRACT FROM AUTHOR]

Social media has gained widespread recognition for its importance in the medical field. Such platforms play an important role for learning and teaching, because knowledge can be transmitted instantly and massively, and specialists in different world-wide locations can discuss experiences instantaneously. The present article presents our experience of using social media to facilitate surgical learning while encouraging leadership and global mentoring. This retrospective descriptive study was initiated at the time of the creation of our social media handle on Twitter, February 22, 2019. Since that time, we have posted 10,587 academic tweets; the monthly growth rate has been 9% (393 new followers per month). Currently, we have 4,213 followers, 11,241,000 impressions, 121,105 visits, and 121,105 mentions. We have reviewed 59 topics of interest in general surgery and 132 clinical cases in trauma, as well as in hepatobiliary, gastrointestinal, thoracic, and acute-care surgery. We have made 13 image challenges using illustrations of diagnostic and intraoperative images. Although the evidence is uncertain to promote education performed entirely through social media, we show that @Cirbosque has been effective, and the impact of this initiative on Twitter is appreciated by many surgeons worldwide, including renowned teachers in each of the topics addressed. Furthermore, the number of participants in the discussions increased each day, as did all impact indicators according to Twitter Analytics. Thus, we conclude that the educational message of @Cirbosque is having a positive effect and reaching thousands of people worldwide, suggesting that others can develop similar outreach programs in education and communication. [ABSTRACT FROM AUTHOR]

Resumo Justificativa A isquemia miocárdica perioperatória é comum em pacientes submetidos à cirurgia de fratura de quadril. Nosso objetivo foi avaliar a eficácia do bloqueio perioperatório contínuo do plexo lombar na redução do risco de eventos cardíacos isquêmicos em pacientes idosos submetidos à cirurgia para fraturas de quadril, expresso como uma redução de eventos isquêmicos por indivíduo. Métodos Pacientes com mais de 60 anos de idade, ASA II–III com fatores de risco para ou com doença coronariana conhecida foram incluídos neste estudo controlado e randomizado. Os pacientes foram aleatorizados para analgesia convencional usando analgésicos opioides para administração de analgesia intravenosa controlada pelo paciente ( Intravenous Patient‐Controlled Analgesia – IVPCA) ou analgesia contínua com o bloqueio do Plexo Lombar (PL), ambas iniciadas no pré‐operatório e mantidas até o terceiro dia de pós‐operatório. Monitoração contínua de ECG com análise do segmento ST foi registrada. Enzimas cardíacas seriadas e escores de dor foram registrados durante todo o período. Medimos a incidência de eventos isquêmicos por indivíduo registrados com monitoração contínua do segmento ST via Holter. Resultados Trinta e um pacientes (IVPCA 14, PL 17) foram incluídos. Não houve eventos cardíacos sérios durante o período de observação. O número de eventos isquêmicos registrados por sujeito durante o período de observação foi de seis no grupo PL e três no grupo IVPCA. Essa diferença não foi estatisticamente significativa ( p = 0,618). Não houve diferenças estatisticamente significativas no número de casos com aumento dos valores de troponina no perioperatório (três casos no grupo LP e um caso no grupo IVPCA) ou em termos de escores de dor. Conclusões O uso da analgesia perineural contínua comparado ao da analgesia sistêmica convencional não modifica a incidência de eventos isquêmicos cardíacos no período perioperatório de pacientes idosos com fratura de quadril. Background Perioperative myocardial ischemia is common among patients undergoing hip fracture surgery. Our aim is to evaluate the efficacy of perioperative continuous lumbar plexus block in reducing the risk of cardiac ischemic events of elderly patients undergoing surgery for hip fractures, expressed as a reduction of ischemic events per subject. Methods Patients older than 60 years, ASA II–III, with risk factors for or known coronary artery disease were enrolled in this randomized controlled study. Patients were randomized to conventional analgesia using opioid intravenous patient‐controlled analgesia or continuous lumbar plexus block analgesia, both started preoperatively and maintained until postoperative day three. Continuous electrocardiogram monitoring with ST segment analysis was recorded. Serial cardiac enzymes and pain scores were registered during the entire period. We measured the incidence of ischemic events per subject registered by a continuous ST‐segment Holter monitoring. Results Thirty‐one patients (intravenous patient‐controlled analgesia 14, lumbar plexus 17) were enrolled. There were no major cardiac events during the observation period. The number of ischemic events recorded by subject during the observation period was 6 in the lumbar plexus group and 3 in the intravenous patient‐controlled analgesia group. This difference was not statistically significant ( p = 0.618). There were no statistically significant differences in the number of cases with increased perioperative troponin values (3 cases in the lumbar plexus group and 1 case in the intravenous patient‐controlled analgesia group) or in terms of pain scores. Conclusions Using continuous perineural analgesia, compared with conventional systemic analgesia, does not modify the incidence of perioperative cardiac ischemic events of elderly patients with hip fracture. [ABSTRACT FROM AUTHOR]

The soling can negatively affect the performance of photovoltaic systems. We studied the species, which deposit on photovoltaic (PV) modules in northern Chile (Atacama Desert). The environmental conditions are the base for the interaction of dust particles and the module’s surfaces. We considered 4 locations for the study. We determined that the particle size of the dust to deposit on PV modules is smaller than 63 μm for all the selected sites. However, the morphology varies from place to place influencing optical response of the modules. After 4 months dust accumulation the transmittance of PV glass reduced by 55%. [ABSTRACT FROM AUTHOR]

Fischer and Heun [SICOMP 2011] proposed the first Range Minimum Query (RMQ) data structure on an array A [ 1 , n ] that uses 2 n + o ( n ) bits and answers queries in O ( 1 ) time without accessing A . Their scheme converts the Cartesian tree of A into a general tree, which is represented using DFUDS. We show that, by using instead the BP representation, the formula becomes simpler since border conditions are eliminated. We also improve the current implementation of the BP representation for this purpose. This leads to the fastest and most compact practical implementation to date. [ABSTRACT FROM AUTHOR]

Knowledge and experience are vital assets within the construction industry. Nevertheless, small and medium construction companies still have problems to transfer the knowledge acquired in their projects to the rest of the organization. Lessons-learned are elements of knowledge management that could help companies to improve this process, and therefore, their global performance. This research presents a cloud-based mobile shared workspace to support knowledge management in construction. The article presents the original system and the modifications made to it based on an initial evaluation by construction professionals. The main upgrades were to include a notification system, letting users know when an action is required from them, and to improve the synchronization process for a better offline experience on site. The evaluators considered these were essentials features to be able to use the system on site. The 2.0 version of the system was validated with construction experts. The article concludes that one of the most relevant features of the system is its capacity to save information on site without an internet connection for later synchronization. Also, the proposed cloud-based shared workspace is a feasible option to improve knowledge management in small and medium Chilean construction companies, mainly because of mobility, usability and investment-related factors. [ABSTRACT FROM AUTHOR]

Today we are facing an increasingly uncertain world that can pose a threat to any business, but also an instance to leverage and generate new opportunities. Risk Management (RM) understands that present decisions and actions can influence the future, by identifying opportunities and threats. This paper addresses these issues with regards to the procurement and contract management of construction services in the mining industry, considering that this industry has not yet established a systematic framework for the application of RM in these functions. This situation results in the lack of knowledge about RM performance and gaps in procurement and contracting, making an evaluation and monitoring system of this function a needed methodology. With such a system, gaps in RM can be identified, improvement actions recommended and performance controlled. Then, a prototype evaluation system has been constructed based on maturity models where the evaluation is based on 1) a knowledge-based system that is able to propose actions to overcome current limitations of the RM function, and 2) a monitoring approach that is able to show the evolution of the RM function with the goal of improving it continuously. The maturity model and the prototype system used for this evaluation are described and results from two case studies corresponding to two mining companies are discussed. Also, main conclusions obtained from their analysis are presented. The prototype system has been validated through these cases and it might become the basis for the construction of a more functional system that could improve RM in procurement and contracting management in the future. These mining companies have considered the prototype as a useful tool because it establishes a framework for RM in the management of procurement and contracting processes, it can generate a systematic evaluation of RM in this area, and it is of easy access and use. [ABSTRACT FROM AUTHOR]

Construction projects are an important source of organizational knowledge. Though, it is common to find that most lessons learned in construction projects are lost because most companies never take care of collecting them. To change this situation, a mobile lesson-learned system application with interface for smartphones and web in a cloud environment is proposed. This article focuses on the design of a prototype of the system and the main characteristics of its architecture. It is concluded that the application of mobile technology on the field would facilitate the use of the system, been an appropriate tool for knowledge management. [ABSTRACT FROM AUTHOR]

Fourteen percent cases in a relapsing polychondritis (RP) cohort can be classified as MAGIC syndrome. Patients with MAGIC syndrome have higher likelihood of having clinical features of Behcet's disease (BD). Patients with MAGIC syndrome have features unique to both RP and BD, including aortitis, Raynaud's phenomena and elevated anti-collagen II antibodies. Fulfillment of either McAdam's or Damiani's Criteria for RP plus the International Criteria for Behçet's Disease have excellent sensitivity to classify MAGIC syndrome. Mouth and genital ulcers with inflamed cartilage (MAGIC) syndrome is characterized by overlapping features of relapsing polychondritis (RP) and Behcet's disease (BD). To date, no studies have defined the clinical spectrum of disease in a cohort of patients with MAGIC syndrome. Adult patients within an ongoing prospective, observational cohort study in RP were clinically assessed for MAGIC syndrome. A systematic review was conducted to identify additional cases of MAGIC syndrome by searching four databases: PubMed (US National Library of Medicine), Embase (Elsevier), Scopus (Elsevier) and Web of Science: Core Collection (Clarivate Analytics). The inclusion criteria used were: [1] patients of any age or gender who were diagnosed with MAGIC syndrome, or both RP and BD; [2] case report or case series study; [3] published from 1985 – July 2020; and [4] in English language. Risk of bias was assessed using a checklist developed by the authors and based on the Consensus-based Clinical Case Reporting (CARE) Guidelines. Search results screening, article inclusion, data extraction and risk of bais assessment was performed independently by two investigators. Clinical characteristics, particularly BD-related features, were compared between patients with MAGIC syndrome and cases of non-MAGIC RP. The performance characteristics of different criteria to classify MAGIC syndrome were also evaluated. Out of 96 patients with RP, 13 (14%) patients were diagnosed with MAGIC syndrome. For the systematic review, 380 articles were retrieved of which 90 were screened at title and abstract levels. Of these screened, 60 were excluded and 30 proceeded to full text review where an additional 8 were excluded. Twenty-two articles were included in our review and from which 27 additional cases of MAGIC syndrome were identified. Pooling all 40 cases together and comparing them with non-MAGIC RP, there was a significantly higher prevalence of ocular involvement (28% vs 4%, p <0.01), cutaneous involvement (35% vs 1%, p <0.01), GI involvement (23% vs 4%, p <0.01), and CNS involvement (8% vs 0, p = 0.04) in MAGIC syndrome. A higher prevalence of aortitis (23% vs 1%, p <0.01), Raynaud's phenomenon (54% vs 11%, p <0.01), and elevated anti-collagen II antibodies (50% vs 9%, p = 0.04) were observed in MAGIC syndrome. Fulfillment of either McAdam's or Damiani's Criteria for RP plus the International Criteria for Behçet's Disease had excellent sensitivity (98%) to classify cases of MAGIC syndrome. A substantial proportion of patients with RP can be clinically diagnosed with MAGIC syndrome. These patients have features of RP, BD, and other unique features including aortitis, Raynaud's phenomenon and elevated anti-collagen II antibodies. [ABSTRACT FROM AUTHOR]

Abstract: In this work we characterize height-selective emitters. The concept of a height-selective emitter is similar to the classical selective emitter but applied on a much smaller scale. Concretely, we masked textured wafers by a spin coating oxide. Scanning electron microscopy (SEM) analysis revealed that only the valleys between the tips of the pyramids are covered by the oxide while the tips are open. Thus, subsequent phosphorus diffusion leads to a highly doped emitter on the tips of the pyramids, and a lowly doped emitter at the sides and valleys in between. This was demonstrated by SEM measurements on cross section prepared samples. Further characterization consisted of IV, spectral response, and contact resistivity measurements as well as the determination of the silver crystallites’ distribution, both on height-selective and standard emitter cells with different emitter sheet resistances. In contrast to homogeneous emitter cells, height-selective emitter cells, although exhibiting a high macroscopical sheet resistance, could still be well contacted by standard silver pastes. Just a few silver crystallites at the tips of the pyramids allowed a good contact. Up to 110Ω/sq fill factors higher than 77.5% could be achieved. The last part of the characterization consisted of carrier lifetime measurements on standard and height-selective emitter samples with symmetric structures to determine the implied open circuit voltage, emitter saturation current density and effective lifetime to identify limiting factors such as emitter, front, and back surface recombination. These measurements demonstrated that height-selective emitters benefit from a lower recombination in the emitter allowing a higher open circuit voltage. [Copyright &y& Elsevier]

The estimation of daily solar radiation is needed in many studies related to solar power plant placements. To optimize photovoltaic (PV) systems, their placement must be as efficient as possible in terms of the prevailing meteorological conditions. There are situations where radiation data are not available, as in the case of desert areas, suitable for the operation of PV systems. In this work, daily global solar radiation has been estimated in desert areas using Artificial Neural Networks (ANN), where the inputs used are daily minimum and maximum temperatures and extraterrestrial radiation. The ANN model is validated with data from deserts in Chile, Israel, Saudi Arabia, South Africa and Australia. The results show that the average Relative Root-Mean-Square Deviation (RRMSD) value is 13%, the average Relative Mean Bias Difference (RMBE) value is less than 4% and the average correlation coefficient (r) value is about 0.8. [ABSTRACT FROM AUTHOR]

We present strong arguments and experimental findings for the definition of a photovoltaic module accelerated ageing procedure for high irradiance and desert conditions to create a Desert Label for the particular Atacama Desert climatic conditions. A special focus on high ultraviolet solar radiation dosage in combination with either damp heat, salt mist or aggressive thermal cycling are presented. Indoor experimental results, strengthened by outdoor monitoring of sister mini-modules at the Atacama Desert, allowed selecting the appropriate ageing tests while exploring the reliability and durability of a wide range of module configurations, including various typical encapsulants, high efficiency cell technologies and module designs, for industrial applications. • Some heterojunction solar cells are sensitive to UV light. • Good correlations between indoor UV ageing and outdoor results are reported. • Much higher UV dose than the IEC61215 are required for PV modules dedicated to Desert conditions. • No synergy have been detected between UV and moisture from indoor and outdoor results. • Severity 3 salt mist test do not damage our PV modules. [ABSTRACT FROM AUTHOR]