Αρχειοθήκη ιστολογίου

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Παρασκευή 5 Αυγούστου 2016

Energies, Vol. 9, Pages 620: Hysteresis Characteristic in the Hump Region of a Pump-Turbine Model

The hump feature is one of the major instabilities in pump-turbines. When pump-turbines operate in the hump region, strong noise and serious fluctuations can be observed, which are harmful to their safe and stable operation and can even destroy the whole unit as well as water conveyance system. In this paper, a low specific speed (nq = 36.1 min−1) pump-turbine model was experimentally investigated. Firstly, the hump characteristic was obtained under 19 mm guide vane opening conditions. More interestingly, when the hump characteristic was measured in two directions (increasing and decreasing the discharge), characteristic hysteresis was found in the hump region. The analysis of performance characteristics reveals that the hump instability is the result of Euler momentum and hydraulic losses, and different Euler momentum and hydraulic losses in the two development processes lead to the hysteresis phenomenon. Then, 12 pressure sensors were mounted in the different parts of the pump-turbine model to obtain the time and frequency characteristics. The analysis of the corresponding fast Fourier transform confirms that the hump characteristic is related to low-frequency (0.04–0.15 times rotational frequency) vortices. The occurrence and cessation of vortices depend on the operating condition and measurement direction, which contribute to the hysteresis feature. Finally, the type of the low-frequency vortices was analyzed through the cross power spectrum.

http://ift.tt/2b7DSit

Social Sciences, Vol. 5, Pages 41: Piracy and the Politics of Social Media

Since the 1990s, the understanding of how and where politics are made has changed radically. Scholars such as Ulrich Beck and Maria Bakardjieva have discussed how political agency is enacted outside of conventional party organizations, and political struggles increasingly focus on single issues. Over the past two decades, this transformation of politics has become common knowledge, not only in academic research but also in the general political discourse. Recently, the proliferation of digital activism and the political use of social media are often understood to enforce these tendencies. This article analyzes the Pirate Party in relation to these theories, relying on almost 30 interviews with active Pirate Party members from different parts of the world. The Pirate Party was initially formed in 2006, focusing on copyright, piracy, and digital privacy. Over the years, it has developed into a more general democracy movement, with an interest in a wider range of issues. This article analyzes how the party's initial focus on information politics and social media connects to a wider range of political issues and to other social movements, such as Arab Spring protests and Occupy Wall Street. Finally, it discusses how this challenges the understanding of information politics as a single issue agenda.

http://ift.tt/2ayG0hd

Beverages, Vol. 2, Pages 22: Fruit Juice Production Using Ultraviolet Pasteurization: A Review

Ultraviolet (UV-C at 253.7 nm) technology has been the go-to alternative pasteurization and shelf-life extension treatment for beverages for the last two decades. It has been the focal point of non-thermal methods for fruit juice processing and has been studied extensively. UV-C technology has been proven to produce microbiologically safe products with minimal negative impact towards quality of the products. However, due to the physicochemical characteristics of fruit juice, application of UV-C does have certain limitations and thus, there is a need to further study the effects of UV-C-treatment and equipment design. Critical decisions on the type of fruit product, juice color, juice composition, and juice physical characteristics, among other variables, are imperative to produce a safe and wholesome juice. Therefore, this paper serves as a source for development of UV-C technology for pasteurization and shelf-life extension of fruit juice to successfully obtain a final product with minimal changes of its nutritional component without neglecting the microbial safety. It reviews previous literatures involving ultraviolet-treated fruit juices, ranging from popular apple and orange juice to lesser-known pummelo and pitaya juice. The review also covers the aspect of microbiological and chemical safety, quality, and sensory characteristics as well as hurdle technology involving UV-C as the main method and the market potential with its cost implication of UV-C technology.

http://ift.tt/2amZSsm

Cosmetics, Vol. 3, Pages 28: Oxidative Stress and Human Skin Connective Tissue Aging

Everyone desires healthy and beautiful-looking skin. However, as we age, our skin becomes old due to physiological changes. Reactive oxygen species (ROS) is an important pathogenic factor involved in human aging. Human skin is exposed to ROS generated from both extrinsic sources such as as ultraviolet (UV) light from the sun, and intrinsic sources such as endogenous oxidative metabolism. ROS-mediated oxidative stress damages the collagen-rich extracellular matrix (ECM), the hallmark of skin connective tissue aging. Damage to dermal collagenous ECM weakens the skin's structural integrity and creates an aberrant tissue microenvironment that promotes age-related skin disorders, such as impaired wound healing and skin cancer development. Here, we review recent advances in our understanding of ROS/oxidative stress and skin connective tissue aging.

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Prevalence of hepatitis B virus in the Kurram Agency, Pakistan: A 5-year observational study in a war-affected region

Journal of Clinical Virology

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Predictive factors of severe complications for ampullary, bile duct and duodenal cancers following pancreaticoduodenectomy: Multivariate analysis of a 10-year multicentre retrospective series

The Surgeon

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Sepsis in cirrhosis: Emerging concepts in pathogenesis, diagnosis and management

Hepatology International

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Isolated Roux-en-Y reconstruction versus conventional reconstruction after pancreaticoduodenectomy

The Surgeon

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Computed tomography findings for a gastric lymphoepithelioma-like carcinoma: How often does it present as a submucosal mass

European Radiology

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Release of infectious hepatitis C virus from Huh7 cells occurs via a trans-Golgi network-to-endosome pathway independent of very-low-density lipoprotein secretion

Journal of Virology

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A novel method for pain relief in chronic pancreatitis: An old drug in a new pack: A controlled study

Indian Journal of Surgery

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Cross-cultural adaptation and validation of the italian version of swal-qol

Dysphagia

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Cervical osteophytes increase the risk for foreign body impaction: A 171-patient case-control study

Dysphagia

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A case of remission from pre-diabetes following intermittent hypoxic training

Obesity Research & Clinical Practice

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Post Roux-en Y gastric bypass complications: A comparative study assessing the clinical effectiveness of oesophagogastroduodenoscopy and oral-contrast swallow

The Surgeon

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Perioperative outcomes of esophageal cancer surgery in a mid-volume institution in the era of centralization

Langenbeck's Archives of Surgery

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Early splenic flexure intubation competency predicts early cecal intubation competency in gastroenterology fellows

Digestive Diseases and Sciences

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Use of video-based education and tele-health home monitoring after liver transplantation: Results of a novel pilot study

Surgery

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Safety and efficacy of a same-day low-volume 1 l peg bowel preparation in colonoscopy for the elderly people and people with renal dysfunction

Digestive Diseases and Sciences

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A pilot study of the head extension swallowing exercise: new method for strengthening swallowing-related muscle activity

Dysphagia

http://ift.tt/2aY8gjn

Serial measurement of Wisteria floribunda agglutinin positive Mac-2-binding protein is useful for predicting liver fibrosis and the development of hepatocellular carcinoma in chronic hepatitis C patients treated with IFN-based and IFN-free therapy

Hepatology International

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Reflex cough and disease duration as predictors of swallowing dysfunction in Parkinson's disease

Dysphagia

http://ift.tt/2aY857G

Incidence, risk factors and outcomes of acute kidney injury (AKI) in patients with acute-on-chronic liver failure (ACLF) of underlying cirrhosis

Hepatology International

http://ift.tt/2b04F0M

A systematic review of the role of re-laparoscopy in the management of complications following laparoscopic colorectal surgery

The Surgeon

http://ift.tt/2aY8fvS

Morphological and molecular identification of nasopharyngeal bot fly larvae infesting red deer ( Cervus elaphus ) in Austria

Abstract

Nasopharyngeal myiases are caused by larvae of bot flies (Diptera: Oestridae), which have evolved a high specificity for their hosts. Bot flies (n = 916) were collected from 137 (57.6 %) out of 238 red deer (Cervus elaphus) hunted in Vorarlberg and Tyrol (Western Austria). After being stored in 75 % ethanol, larvae were identified to species level and developmental stage using morphological and morphometric keys. Larvae were also molecularly characterized by polymerase chain reaction (PCR) amplification and partial sequencing of the mitochondrial cytochrome oxidase subunit I gene. Morphological and molecular analysis allowed identification of larvae as Cephenemyia auribarbis and Pharyngomyia picta. Genetic variations were also examined within the specimens collected in both geographical locations.



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Antimalarial potential of leaves of Chenopodium ambrosioides L.

Abstract

In an effort to identify novel therapeutic alternatives for the treatment of malaria, the present study evaluated the antimalarial effect of the crude hydroalcoholic extract (HCE) from the leaves of Chenopodium ambrosioides L. For this purpose, the molecular affinity between the total proteins from erythrocytes infected with Plasmodium falciparum and HCE or chloroquine was evaluated by surface plasmon resonance (SPR). Subsequently, the plasmodicidal potential of HCE was assessed in a P. falciparum culture. Using BALB/c mice infected with Plasmodium berghei intraperitoneally (ip.), we evaluated the effects of ip. treatment, for three consecutive days (day 7, 8, and 9 after infection), with chloroquine (45 mg/kg) or HCE (5 mg/kg), considering the survival index and the parasitaemia. The groups were compared to an untreated control group that receives only PBS at the same periods. The results indicated that HCE could bind to the total proteins of infected erythrocytes and could inhibit the parasite growth in vitro (IC50 = 25.4 g/mL). The in vivo therapeutic treatment with HCE increased the survival and decreased the parasitaemia in the infected animals. Therefore, the HCE treatment exhibited a significant antiplasmodial effect and may be considered as a potential candidate for the development of new antimalarial drugs.



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Microbiota from Rhabditis regina may alter nematode entomopathogenicity

Abstract

Here we report the presence of the entomopathogenic nematode Rhabditis (Rhabditoides) regina affecting white grubs (Phyllophaga sp. and Anomala sp.) in Mexico and R. regina-associated bacteria. Bioassays were performed to test the entomopathogenic capacity of dauer and L2 and L3 (combined) larval stages. Furthermore, we determined the diversity of bacteria from laboratory nematodes cultivated for 2 years (dauer and L2–L3 larvae) and from field nematodes (dauer and L2–L3 larvae) in addition to the virulence in Galleria mellonella larvae of some bacterial species from both laboratory and field nematodes. Dauer and non-dauer larvae of R. regina killed G. mellonella. Bacteria such as Serratia sp. (isolated from field nematodes) and Klebsiella sp. (isolated from larvae of laboratory and field nematodes) may explain R. regina entomopathogenic capabilities. Different bacteria were found in nematodes after subculturing in the laboratory suggesting that R. regina may acquire bacteria in different environments. However, there were some consistently found bacteria from laboratory and field nematodes such as Pseudochrobactrum sp., Comamonas sp., Alcaligenes sp., Klebsiella sp., Acinetobacter sp., and Leucobacter sp. that may constitute the nematode microbiome. Results showed that some bacteria contributing to entomopathogenicity may be lost in the laboratory representing a disadvantage when nematodes are cultivated to be used for biological control.



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Rewards Boost Sustained Attention through Higher Effort: A Value-based Decision Making Approach

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Publication date: Available online 4 August 2016
Source:Biological Psychology
Author(s): Stijn A.A. Massar, Julian Lim, Karen S. Sasmita, Michael W.L. Chee
Maintaining sustained attention over time is an effortful process limited by finite cognitive resources. Recent theories describe the role of motivation in the allocation of such resources as a decision process: the costs of effortful performance are weighed against its gains. We examined this hypothesis by combining methods from attention research and decision neuroscience. Participants first performed a sustained attention task at different levels of reward. They then performed a reward-discounting task, measuring the subjective costs of performance. Results demonstrated that higher rewards led to improved performance (Exp1, 2, 3), and enhanced attentional effort (i.e. pupil diameter; Exp2 & 3). Moreover, discounting curves constructed from the choice task indicated that subjects devalued rewards that came at the cost of staying vigilant for a longer duration (Exp1 & 2). Motivation can thus boost sustained attention through increased effort, while sustained performance is regarded as a cost against which rewards are discounted.



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Water, Vol. 8, Pages 333: Assessment of Water Rights and Irrigation Pricing Reforms in Heihe River Basin in China

The purpose of this paper is to understand the progress of water rights and irrigation pricing reform in Heihe River Basin (HRB) and their influence on irrigation application. The data came from a village and household level survey conducted in 2009 and 2014 in five counties in Zhangye City, HRB. The main component of reforming water rights was issuing water certificates to individual farmers. However, the share of villages that have done so dropped from 70% in 2004 to 28% in 2014. Water pricing reform raised the price of water. For the pricing of surface water, which consists of an area-based fee and a volumetric price, the volumetric price was increased. Econometric results show that amending water rights substantially reduced irrigation application in the early stage of reform (by 2009) but not in the later phase (by 2014). In contrast, higher water prices lowered irrigation applications significantly at both the early and later stages. Further analysis indicates that due to ineffective implementation, high cost of implementation due to large number of farmers, variations in water supply from year to year, and small farm sizes, little benefit is gained from trading. All of these factors played a role in the failure of water rights reforms.

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Remote Sensing, Vol. 8, Pages 641: Wavelet Based Analysis of TanDEM-X and LiDAR DEMs across a Tropical Vegetation Heterogeneity Gradient Driven by Fire Disturbance in Indonesia

Three-dimensional information provided by TanDEM-X interferometric phase and airborne Light Detection and Ranging (LiDAR) Digital Elevation Models (DEMs) were used to detect differences in vegetation heterogeneity through a disturbance gradient in Indonesia. The range of vegetation types developed as a consequence of fires during the 1997–1998 El Niño. Two-point statistic (wavelet variance and co-variance) was used to assess the dominant spatial frequencies associated with either topographic features or canopy structure. DEMs wavelet spectra were found to be sensitive to canopy structure at short scales (up to 8 m) but increasingly influenced by topographic structures at longer scales. Analysis also indicates that, at short scale, canopy texture is driven by the distribution of heights. Thematic class separation using the Jeffries–Matusita distance (JM) was greater when using the full wavelet signature (LiDAR: 1.29 ≤ JM ≤ 1.39; TanDEM-X: 1.18 ≤ JM ≤ 1.39) compared to using each decomposition scale individually (LiDAR: 0.1 ≤ JM ≤ 1.26; TanDEM-X: 0.1 ≤ JM ≤ 1.1). In some cases, separability with TanDEM-X was similar to the higher resolution LiDAR. The study highlights the potential of 3D information from TanDEM-X and LiDAR DEMs to explore vegetation disturbance historywhen analyzed using two-point statistics.

http://ift.tt/2aNcSFO

Energies, Vol. 9, Pages 621: Automated Variable Selection and Shrinkage for Day-Ahead Electricity Price Forecasting

In day-ahead electricity price forecasting (EPF) variable selection is a crucial issue. Conducting an empirical study involving state-of-the-art parsimonious expert models as benchmarks, datasets from three major power markets and five classes of automated selection and shrinkage procedures (single-step elimination, stepwise regression, ridge regression, lasso and elastic nets), we show that using the latter two classes can bring significant accuracy gains compared to commonly-used EPF models. In particular, one of the elastic nets, a class that has not been considered in EPF before, stands out as the best performing model overall.

http://ift.tt/2aztMem

Photonics, Vol. 3, Pages 48: Photodynamic Therapy-Induced Microvascular Changes in a Nonmelanoma Skin Cancer Model Assessed by Photoacoustic Microscopy and Diffuse Correlation Spectroscopy

One of the main mechanisms of action for photodynamic therapy (PDT) is the destruction of tumor vasculature. We observed the PDT-induced vasculature destruction in a mouse model of skin cancer using two techniques: Photoacoustic microscopy (PAM) and diffuse correlation spectroscopy (DCS). PAM showed high-resolution images of the abnormal microvasculature near the establishing tumor area at pre-PDT, as well as the subsequent destruction of those vessels post-PDT. DCS indicated a significant blood flow decrease after PDT, confirming the vascular destruction. Noninvasive assessment of vascular changes may be indicative of therapy response.

http://ift.tt/2aNchUR

IJERPH, Vol. 13, Pages 787: A Framework for Flood Risk Analysis and Benefit Assessment of Flood Control Measures in Urban Areas

Flood risk analysis is more complex in urban areas than that in rural areas because of their closely packed buildings, different kinds of land uses, and large number of flood control works and drainage systems. The purpose of this paper is to propose a practical framework for flood risk analysis and benefit assessment of flood control measures in urban areas. Based on the concept of disaster risk triangle (hazard, vulnerability and exposure), a comprehensive analysis method and a general procedure were proposed for urban flood risk analysis. Urban Flood Simulation Model (UFSM) and Urban Flood Damage Assessment Model (UFDAM) were integrated to estimate the flood risk in the Pudong flood protection area (Shanghai, China). S-shaped functions were adopted to represent flood return period and damage (R-D) curves. The study results show that flood control works could significantly reduce the flood risk within the 66-year flood return period and the flood risk was reduced by 15.59%. However, the flood risk was only reduced by 7.06% when the flood return period exceeded 66-years. Hence, it is difficult to meet the increasing demands for flood control solely relying on structural measures. The R-D function is suitable to describe the changes of flood control capacity. This frame work can assess the flood risk reduction due to flood control measures, and provide crucial information for strategy development and planning adaptation.

http://ift.tt/2aztjJf

Micromachines, Vol. 7, Pages 133: A Modified Lattice Configuration Design for Compact Wideband Bulk Acoustic Wave Filter Applications

High-performance bulk acoustic wave (BAW) filters have been widely applied in the advanced radio frequency (RF) wireless communication systems in the past decade. However, the demand for filters with large bandwidth, up to 10%, still puts a significant stress on the typical aluminum nitride (AlN)-based BAW filters. In this work, a modified lattice configuration is proposed to achieve a wideband filter response using AlN-based BAW resonators. The single stage of this novel topology comprises two auxiliary inductors paralleled in the balanced input and output of the conventional lattice topology. In multi-stage configuration, adjacent two auxiliary inductors can be combined into one; thus, the number of auxiliary inductors decreases exponentially, enabling the compact integration of filter chips. The circuit analysis is performed to reveal the working principle of this configuration. The systematic design methodology is developed ranging from the schematic design to the electromagnetic (EM) simulation. For proof-of-concept validation purposes, a prototype film bulk acoustic wave filter in this configuration is designed and fabricated. The measured 3-dB bandwidth is 400 MHz at the central frequency of 3.25 GHz (12.3% relative bandwidth), which demonstrates a huge superiority in contrast with the conventional ladder and lattice topologies.

http://ift.tt/2aNchEl

Entropy, Vol. 18, Pages 285: ECG Classification Using Wavelet Packet Entropy and Random Forests

The electrocardiogram (ECG) is one of the most important techniques for heart disease diagnosis. Many traditional methodologies of feature extraction and classification have been widely applied to ECG analysis. However, the effectiveness and efficiency of such methodologies remain to be improved, and much existing research did not consider the separation of training and testing samples from the same set of patients (so called inter-patient scheme). To cope with these issues, in this paper, we propose a method to classify ECG signals using wavelet packet entropy (WPE) and random forests (RF) following the Association for the Advancement of Medical Instrumentation (AAMI) recommendations and the inter-patient scheme. Specifically, we firstly decompose the ECG signals by wavelet packet decomposition (WPD), and then calculate entropy from the decomposed coefficients as representative features, and finally use RF to build an ECG classification model. To the best of our knowledge, it is the first time that WPE and RF are used to classify ECG following the AAMI recommendations and the inter-patient scheme. Extensive experiments are conducted on the publicly available MIT–BIH Arrhythmia database and influence of mother wavelets and level of decomposition for WPD, type of entropy and the number of base learners in RF on the performance are also discussed. The experimental results are superior to those by several state-of-the-art competing methods, showing that WPE and RF is promising for ECG classification.

http://ift.tt/2azu6Kg

Micromachines, Vol. 7, Pages 134: Integration of a Droplet-Based Microfluidic System and Silicon Nanoribbon FET Sensor

We present a novel microfluidic system that integrates droplet microfluidics with a silicon nanoribbon field-effect transistor (SiNR FET), and utilize this integrated system to sense differences in pH. The device allows for selective droplet transfer to a continuous water phase, actuated by dielectrophoresis, and subsequent detection of the pH level in the retrieved droplets by SiNR FETs on an electrical sensor chip. The integrated microfluidic system demonstrates a label-free detection method for droplet microfluidics, presenting an alternative to optical fluorescence detection. In this work, we were able to differentiate between droplet trains of one pH-unit difference. The pH-based detection method in our integrated system has the potential to be utilized in the detection of biochemical reactions that induce a pH-shift in the droplets.

http://ift.tt/2aNcOGb

Forests, Vol. 7, Pages 171: Aftermath of Mountain Pine Beetle Outbreak in British Columbia: Stand Dynamics, Management Response and Ecosystem Resilience

The mountain pine beetle (Dendroctonus ponderosae Hopkins) (MPB) has infested and killed millions of hectares of lodgepole pine (Pinus contorta var. latifolia Engelm) forests in British Columbia, Canada, over the past decade. It is now spreading out of its native range into the Canadian boreal forest, with unknown social, economic and ecological consequences. This review explores the ramifications of the MPB epidemic with respect to mid-term timber supply, forest growth, structure and composition, vegetation diversity, forest fire, climate change, and ecosystem resilience. Research confirms that, in British Columbia, all of these variables are more significantly impacted when salvage logging is used as management response to the outbreak. We conclude that appropriate management in response to MPB is essential to ensuring ecologically resilient future forests and reliable mid-term timber supplies for affected human communities. We highlight knowledge gaps and avenues for research to advance our understanding in support of sustainable post-disturbance forest management policies in British Columbia and elsewhere.

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Medicines, Vol. 3, Pages 21: Why We Need Minimum Basic Requirements in Science for Acupuncture Education

As enthusiasm for alternatives to pharmaceuticals and surgery grows, healthcare consumers are turning increasingly to physical medicine modalities such as acupuncture. However, they may encounter obstacles in accessing acupuncture due to several reasons, such as the inability to locate a suitable practitioner, insufficient reimbursement for treatment, or difficulty gaining a referral due to perceived lack of evidence or scientific rigor by specialists. Claims made about a range of treatment paradigms outstrip evidence and students in acupuncture courses are thus led to believe that the approaches they learn are effective and clinically meaningful. Critical inquiry and critical analysis of techniques taught are often omitted, leading to unquestioning acceptance, adoption, and implementation into practice of approaches that may or may not be rational and effective. Acupuncture education for both licensed physicians (DOs and MDs) and non-physicians needs to include science (i.e., explanation of its effects based on contemporary explanations of biological processes), evidence, and critical thinking. Erroneous notions concerning its mechanisms such as moving "stuck Qi (Chi)" or "energy" with needles and that this energy stagnates at specific, tiny locations on the body called acupuncture points lead to mistakes in methodologic design. For example, researchers may select sham and verum point locations that overlap considerably in their neural connections, leading to nonsignificant differences between the two interventions. Furthermore, attributing the effects of acupuncture to metaphorical and arcane views of physiology limits both acceptance and validation of acupuncture in both research and clinical settings. Finally, the content and quality of education and clinical exposure across acupuncture programs varies widely, with currently no minimum basic educational requirements in a scientific methodology. Considering the pressures mounting on clinicians to practice in an evidence-based and scientific manner that also demonstrates cost-effectiveness, acupuncture schools and continuing medical education (CME) courses need to provide their students a strong foundation in rational approaches supported by research.

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Computation, Vol. 4, Pages 28: Highly Excited States from a Time Independent Density Functional Method

A constrained optimized effective potential (COEP) methodology proposed earlier by us for singly low-lying excited states is extended to highly excited states having the same spatial and spin symmetry. Basic tenets of time independent density functional theory and its COEP implementation for excited states are briefly reviewed. The amended Kohn–Sham-like equations for excited state orbitals and their specific features for highly excited states are discussed. The accuracy of the method is demonstrated using exchange-only calculations for highly excited states of the He and Li atoms.

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Atmosphere, Vol. 7, Pages 101: GNSS Measurement of Rain Rate by Polarimetric Phase Shift: Theoretical Analysis

In this paper, a novel method for rain rate estimation is researched by polarimetric phase shift of the Global Navigation Satellite System (GNSS). The physical process of GNSS signals propagating through rain-filled medium is investigated, by which the cause of polarimetric phase shift is explored. Then, a theoretical model between polarimetric phase shift Δ ϕ and rain rate R is established and simulated, which is based on the oblate spheroid raindrop model, four different popular raindrop size distribution models and raindrop canting angle distribution across the Space-Earth rain path. Additionally, effects of raindrop size distribution, rain path length, raindrop canting angle and temperature on the Δ ϕ -R relation are discussed systematically. Other factors in the slant path such as ice crystals, melting particles and ionosphere are also researched preliminarily. The results show that polarimetric phase shift of GNSS signals, which has a strong correlation with rain rate, can be used to estimate the rain rate, and these influencing factors, raindrop size distribution, rain path length, raindrop canting angle and temperature, are quite important in the process of rain rate measurement. It can be also found that the effect of ice crystals can be negligible, while that of melting particles should be considered, and though ionosphere effects are not obvious, the ionospheric anomalies cannot be neglected in future experiments. This method has potential applications in real-time, continuous, extreme precipitation reconnaissance and numerical weather prediction.

http://ift.tt/2aVzZRh

Sensors, Vol. 16, Pages 1235: CoDA: Collaborative Data Aggregation in Emerging Sensor Networks Using Bio-Level Voronoi Diagrams

To implement minimum power consumption of the link, cluster heads adopt the multi-hop manner for inter-cluster communication so as to forward the aggregation data to the relay nodes. This paper proposes a collaborative data aggregation in emerging sensor networks using a bio-level Voronoi diagram, which is an energy-efficient data aggregation protocol that integrates topology control, Multiple Access Control (MAC) and routing. The sensor nodes situated in the lower level of the diagram are responsible for listening and gathering data, and should be organized by optimal clustering node. In the inter-cluster communication stage, a particle swarm optimization algorithm is addressed to seek optimal transmission path which could simultaneously achieve the minimization of the maximum next hop distance between two nodes in the routing path and the minimization of the maximum hop count, so the minimization of whole network energy consumption is realized. The results of theoretical analysis and simulation results show that energy efficiency and synchronization accuracy of the proposed algorithm can be much better than with traditional routing protocols, and the energy consumption of nodes in the whole network can be more balanced.

http://ift.tt/2ayrSGS

Biosensors, Vol. 6, Pages 41: Microfluidic Devices for Forensic DNA Analysis: A Review

Microfluidic devices may offer various advantages for forensic DNA analysis, such as reduced risk of contamination, shorter analysis time and direct application at the crime scene. Microfluidic chip technology has already proven to be functional and effective within medical applications, such as for point-of-care use. In the forensic field, one may expect microfluidic technology to become particularly relevant for the analysis of biological traces containing human DNA. This would require a number of consecutive steps, including sample work up, DNA amplification and detection, as well as secure storage of the sample. This article provides an extensive overview of microfluidic devices for cell lysis, DNA extraction and purification, DNA amplification and detection and analysis techniques for DNA. Topics to be discussed are polymerase chain reaction (PCR) on-chip, digital PCR (dPCR), isothermal amplification on-chip, chip materials, integrated devices and commercially available techniques. A critical overview of the opportunities and challenges of the use of chips is discussed, and developments made in forensic DNA analysis over the past 10–20 years with microfluidic systems are described. Areas in which further research is needed are indicated in a future outlook.

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Sensors, Vol. 16, Pages 1237: A Non-Intrusive Pressure Sensor by Detecting Multiple Longitudinal Waves

Pressure vessels are widely used in industrial fields, and some of them are safety-critical components in the system—for example, those which contain flammable or explosive material. Therefore, the pressure of these vessels becomes one of the critical measurements for operational management. In the paper, we introduce a new approach to the design of non-intrusive pressure sensors, based on ultrasonic waves. The model of this sensor is built based upon the travel-time change of the critically refracted longitudinal wave (LCR wave) and the reflected longitudinal waves with the pressure. To evaluate the model, experiments are carried out to compare the proposed model with other existing models. The results show that the proposed model can improve the accuracy compared to models based on a single wave.

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Is uveitis associated with topiramate use? A cumulative review



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Forests, Vol. 7, Pages 172: Baseline Mortality Analysis Reveals Legacy of Contrasting Land Use Practices on the Structural Sustainability of Endangered Moroccan and Spanish Mountain Forests

Disturbances can affect forest health and are important modulating factors of tree responses to environmental changes. However, standard methods are needed to assess and elucidate the relative effects of disturbance legacies on forest health among species. Here, structural sustainability was used to evaluate and to compare the impacts of contrasting disturbances on the health of Quercus ilex, Cedrus atlantica, and Abies pinsapo forest stands in Morocco and Spain. Disturbance effects on structural sustainability were related to type, severity, and land-use history, and showed inter-regional variability. Cedrus atlantica was structurally sustainable in its core distribution in Morocco, but not at its southern and northernmost geographical range limits. Quercus ilex was structurally sustainable in Morocco. Abies pinsapo was structurally sustainable at optimal elevation sites in Morocco (Rif Mts.), but considering the whole A. pinsapo dataset including Morocco and Spain, the species is structurally unsustainable due to excessive mortality. However, at the lower elevation plots in Spain, unsustainability was due to insufficient mortality. Although some forests were structurally sustainable, none of them were deemed healthy because none met their management objectives. Results also support the key role of disturbance regimes as drivers of forest structural sustainability and adaptive capacity.

http://ift.tt/2amT2Du

Water, Vol. 8, Pages 330: Reconstruction of a Storm Map and New Approach in the Definition of Categories of the Extreme Rainfall, Northeastern Sicily

After more than 350 mm of rainfall fell in a few hours on 22 November 2011, thousands of landslides and floods were induced in two main zones of Northeastern Sicily. The total rainfall has been reconstructed integrating available rain gauge data with Tropical Rainfall Measuring Mission (TRMM) satellite data from NASA (National Aeronautics and Space Administration); the landslide distribution in the field has confirmed the pattern of rainfall accumulated on 22 November 2011. Precipitation maxima of 1, 3, 6, 12, and 24 h was recognized as the hazardous events, which marks the evidence of a changing climate, with a shift toward more intense rainfalls in recent times. To investigate the sequence of the annual maxima, the historical time series have been transformed in the Standard normal distribution, from the cumulative probability of the GEV (Generalized Extreme Value) distribution. Following a similar definition of the Standard Precipitation Index (SPI), the transformation of the historical data in the standardized values allows the definition of categories of hourly maxima in term of extreme, severe, moderate, or mild. This transformation allows to eliminate the asymmetry of the time series, so that trends and fluctuations have been highlighted by the progressive accumulation of data (Rescaled Adjust Partial Sum). This statistical approach allows the improvement of the interpretability of the hydrological extreme events, and could also be used in other cases.

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Sustainability, Vol. 8, Pages 753: Cool Marble Building Envelopes: The Effect of Aging on Energy Performance and Aesthetics

Marble envelopes represent a relatively common architectural solution used in variety of historic, modern and contemporary building facades. White marble envelopes have been shown to reduce solar heat gains, while improving indoor thermal comfort and energy efficiency in summer time. While marble is useful in this context, the urban atmosphere accelerates the degradation of marble elements. This leads to changes in optical characteristics, hence the aesthetics, and affects the energy efficiency benefits offered by white marble facades. These issues are investigated in order to predict the impact of degradation on energy performance and to the aesthetic value, such as change of color and luminosity. In this study, surface degradation of white marble is analyzed by means of accelerated weathering in the laboratory while examining changes to the optical characteristics of the materials. A dynamic simulation is carried out to assess the energy performance of a building as a case study.

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Coatings, Vol. 6, Pages 34: An Overview on Corrosion-Resistant Coating Technologies in Biomass/Waste-to-Energy Plants in Recent Decades

Highly efficient electric power generation from biomass/waste fuels becomes an important worldwide issue to prevent global warming. In these plants, severe high-temperature corrosion and erosion-corrosion damage occur in boiler tubes influenced by HCl, SOx gases, and chlorides as contaminants in fuels. Coating technologies become important as a countermeasure for such damage, because of the easy maintenance, cost performance, and ease of application on various materials. In severe corrosive conditions of boilers, formation of dense, homogenous, and tough coating layers, as well as protective oxide layers of corrosion-resistant materials, are important. In the last 30 years, materials and coating processes applied in shop and on site have progressed based on many field observations and the consideration of deterioration mechanisms in order to maintain long lifetimes in the plants. Furthermore, new innovative coatings are now being developed by using advanced precise control, nanotechnologies, etc. This paper introduces recent trends of advanced coating developments and applications, such as weld-overlay, cladding, thermal spray coating, and slurry coating for biomass/waste boilers. Furthermore, the evaluation results of deterioration mechanisms and lifetime of coatings, and the future issue for innovative coatings, are presented.

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IJERPH, Vol. 13, Pages 786: Psychosocial Determinants of Fruit and Vegetable Consumption in a Japanese Population

There is limited evidence in Japan regarding the psychosocial determinants of fruit/vegetable intake. We performed a cross-sectional study of people aged 18 years or older in four regions of Japan; 2308 (men: 1012, women: 1296) individuals who completed the questionnaires were included. We found that 24.8% of people were aware of the current recommendations for vegetables and 13.2% for fruit and that "ability to design meals" and "availability when eating outside of the home" were the most important factors related to self-efficacy and barriers to fruit and vegetable intake, respectively. People with high self-efficacy (OR: 3.16; 95% CI: 2.17, 4.60 for fruit; OR: 4.52; 95% CI: 3.08, 6.64 for vegetables) were more likely to consume more fruit and vegetables. People with high scores on attitude (OR: 1.54; 95% CI: 1.06, 2.24) and social support (OR: 1.59; 95% CI: 1.11, 2.27) were more likely to consume more fruit. People with high perceived barriers (OR: 0.69; 95% CI: 0.48, 0.98) were less likely to consume fruit. This study suggests a need to increase the general population's awareness of the fruit and vegetable intake recommendations; facilitating positive attitudes, self-efficacy, and social support for individuals and strengthening the ability of individuals to design meals with more vegetables and fruit might be useful intervention programs.

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Associated ultrasonographic findings in fetuses with microcephaly due to suspected Zika virus (ZIKV) infection during pregnancy

Abstract

Objective

To describe associated fetal ultrasonographic findings and outcome in a series of cases of fetal microcephaly associated with Zika virus infection.

Methods

Retrospective case series of microcephaly with definite (laboratory evidence) or highly probable (specific neuroimaging findings and negative laboratory results) maternal Zika virus infection. Microcephaly was graded as mild if the head circumference was between 2 and 3 standard deviation (SD) below the mean, and severe if 3 or more SD below the mean. Associated central nervous system (CNS) and extracranial malformations are described.

Results

19 singleton pregnancies fulfilling the inclusion criteria were identified. Severe microcephaly and mild microcephaly were identified in 14 and 5 fetuses, respectively. Additional CNS malformations were present in 17 cases and 7 had extracranial congenital anomalies. Symptoms were reported in 13/19 cases at a gestational age between 5 and 16 weeks. Mean (±SD) gestational age at ultrasound diagnosis was 32.3 ± 5.1 weeks. Amniocentesis was performed in 5 cases at a median gestational age of 31 weeks (range 28-38) and was positive for ZIKV RT-PCR in 2 cases. There were three neonatal deaths and one stillbirth.

Conclusion

In the presence of fetal microcephaly associated with Zika virus infection, CNS malformations are frequently detected.



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