bluuebunny/crossref_metadata_2025 huggingface dataset:
Clipping as re-treatment strategy after treatment of a cerebral aneurysm with the Woven EndoBridge embolization device: case report
Authors: Durner Gregor , Özpeynirci Yigit , Schmitz Bernd , Wirtz Christian Rainer , König Ralph , Pala Andrej
Published: March 2018

Recently, treatment of cerebral aneurysms with the Woven EndoBridge (WEB) device has become an established endovascular strategy. However, over time, neurosurgeons and neuroradiologists will be confronted with the challenge of how to treat aneurysm recanalization. The authors report the case of a 49-year-old woman who underwent re-treatment with clipping after the recanalization of a 4 × 3–mm anterior communicating artery aneurysm that had previously been treated using a 4 × 3 WEB device. In contrast to the authors’ prior experiences with clipping of previously coiled aneurysms, the WEB device was found to have a responsive softness during clip placement, and the aneurysm was more maneuverable. Moreover, evaluation with indocyanine green angiography was easy to perform because of the transparent mesh of the WEB device. No profound scarring or WEB protrusion was noted during surgery, making the procedure easier and less dangerous with regard to additional complications. The authors suggest that re-treatment via clipping should be considered in select cases of aneurysm recurrence after treatment with an intraaneurysmal flow diverter.
Key drivers of patient satisfaction in lumbar spine surgery
Authors: Levin Jay M. , Winkelman Robert D. , Tanenbaum Joseph E. , Benzel Edward C. , Mroz Thomas E. , Steinmetz Michael P.
Published: March 2018

OBJECTIVE

The Patient Experience of Care, composed of 9 dimensions derived from the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey, is being used by the Centers for Medicare & Medicaid Services to adjust hospital reimbursement. Currently, there are minimal data on how scores on the constituent HCAHPS items impact the global dimension of satisfaction, the Overall Hospital Rating (OHR). The purpose of this study was to determine the key drivers of overall patient satisfaction in the setting of inpatient lumbar spine surgery.

METHODS

Demographic and preoperative patient characteristics were obtained. Patients selecting a top-box score for OHR (a 9 or 10 of 10) were considered to be satisfied with their hospital experience. A baseline multivariable logistic regression model was then developed to analyze the association between patient characteristics and top-box OHR. Then, multivariable logistic regression models adjusting for patient-level covariates were used to determine the association between individual components of the HCAHPS survey and a top-box OHR.

RESULTS

A total of 453 patients undergoing lumbar spine surgery were included, 80.1% of whom selected a top-box OHR. Diminishing overall health status (OR 0.63, 95% CI 0.43–0.91) was negatively associated with top-box OHR. After adjusting for potential confounders, the survey items that were associated with the greatest increased odds of selecting a top-box OHR were: staff always did everything they could to help with pain (OR 12.5, 95% CI 6.6–23.7), and nurses were always respectful (OR 11.0, 95% CI 5.3–22.6).

CONCLUSIONS

Patient experience of care is increasingly being used to determine hospital and physician reimbursement. The present study analyzed the key drivers of patient experience among patients undergoing lumbar spine surgery and found several important associations. Patient overall health status was associated with top-box OHR. After adjusting for potential confounders, staff always doing everything they could to help with pain and nurses always being respectful were the strongest predictors of overall satisfaction in this population. These findings highlight opportunities for quality improvement efforts in the spine care setting.
Intraoperative use of transcranial motor/sensory evoked potential monitoring in the clipping of intracranial aneurysms: evaluation of false-positive and false-negative cases
Authors: Chung Jaewoo , Park Wonhyoung , Hong Seok Ho , Park Jung Cheol , Ahn Jae Sung , Kwun Byung Duk , Lee Sang-Ahm , Kim Sung-Hoon , Jeon Ji-Ye
Published: March 2018

OBJECTIVE

Somatosensory and motor evoked potentials (SEPs and MEPs) are often used to prevent ischemic complications during aneurysm surgeries. However, surgeons often encounter cases with suspicious false-positive and false-negative results from intraoperative evoked potential (EP) monitoring, but the incidence and possible causes for these results are not well established. The aim of this study was to investigate the efficacy and reliability of EP monitoring in the microsurgical treatment of intracranial aneurysms by evaluating false-positive and false-negative cases.

METHODS

From January 2012 to April 2016, 1514 patients underwent surgery for unruptured intracranial aneurysms (UIAs) with EP monitoring at the authors’ institution. An EP amplitude decrease of 50% or greater compared with the baseline amplitude was defined as a significant EP change. Correlations between immediate postoperative motor weakness and EP monitoring results were retrospectively reviewed. The authors calculated the sensitivity, specificity, and positive and negative predictive values of intraoperative MEP monitoring, as well as the incidence of false-positive and false-negative results.

RESULTS

Eighteen (1.19%) of the 1514 patients had a symptomatic infarction, and 4 (0.26%) had a symptomatic hemorrhage. A total of 15 patients showed motor weakness, with the weakness detected on the immediate postoperative motor function test in 10 of these cases. Fifteen false-positive cases (0.99%) and 8 false-negative cases (0.53%) were reported. Therefore, MEP during UIA surgery resulted in a sensitivity of 0.10, specificity of 0.94, positive predictive value of 0.01, and negative predictive value of 0.99.

CONCLUSIONS

Intraoperative EP monitoring has high specificity and negative predictive value. Both false-positive and false-negative findings were present. However, it is likely that a more meticulously designed protocol will make EP monitoring a better surrogate indicator of possible ischemic neurological deficits.
Validation of diffusion tensor imaging tractography to visualize the dentatorubrothalamic tract for surgical planning
Authors: Nowacki Andreas , Schlaier Jürgen , Debove Ines , Pollo Claudio
Published: March 2018

OBJECTIVE

The dentatorubrothalamic tract (DRTT) has been suggested as the anatomical substrate for deep brain stimulation (DBS)–induced tremor alleviation. So far, little is known about how accurately and reliably tracking results correspond to the anatomical DRTT. The objective of this study was to systematically investigate and validate the results of different tractography approaches for surgical planning.

METHODS

The authors retrospectively analyzed 4 methodological approaches for diffusion tensor imaging (DTI)–based fiber tracking using different regions of interest in 6 patients with essential tremor. Tracking results were analyzed and validated with reference to MRI-based anatomical landmarks, were projected onto the stereotactic atlas of Morel at 3 predetermined levels (vertical levels −3.6, −1.8, and 0 mm below the anterior commissure–posterior commissure line), and were correlated to clinical outcome.

RESULTS

The 4 different methodologies for tracking the DRTT led to divergent results with respect to the MRI-based anatomical landmarks and when projected onto the stereotactic atlas of Morel. There was a statistically significant difference in the lateral and anteroposterior coordinates at the 3 vertical levels (p < 0.001, 2-way ANOVA). Different fractional anisotropy values ranging from 0.1 to 0.46 were required for anatomically plausible tracking results and led to varying degrees of success. Tracking results were not correlated to postoperative tremor reduction.

CONCLUSIONS

Different tracking methods can yield results with good anatomical approximation. The authors recommend using 3 regions of interest including the dentate nucleus of the cerebellum, the posterior subthalamic area, and the precentral gyrus to visualize the DRTT. Tracking results must be cautiously evaluated for anatomical plausibility and accuracy in each patient.
Value of pituitary gland MRI at 7 T in Cushing’s disease and relationship to inferior petrosal sinus sampling: case report
Authors: Law Meng , Wang Regina , Liu Chia-Shang J. , Shiroishi Mark S. , Carmichael John D. , Mack William J. , Weiss Martin , Wang Danny J. J. , Toga Arthur W. , Zada Gabriel
Published: March 2018

Cushing’s disease is caused by adrenocorticotrophic hormone (ACTH)–secreting pituitary adenomas, which are often difficult to identify on standard 1.5-T or 3-T MRI, including dynamic contrast imaging. Inferior petrosal and cavernous sinus sampling remains the gold standard for MRI-negative Cushing’s disease.

The authors report on a 27-year-old woman with Cushing’s disease in whom the results of standard 1.5-T and 3-T MRI, including 1.5-T dynamic contrast imaging, were negative. Inferior petrosal sinus sampling showed a high central-to-peripheral ACTH ratio (148:1) as well as a right-to-left ACTH gradient (19:1), suggesting a right-sided pituitary microadenoma. The patient underwent 7-T MRI, which showed evidence of a right-sided pituitary lesion with focal hypoenhancement not visualized on 1.5-T or 3-T MRI. The patient underwent an endoscopic endonasal transsphenoidal operation, with resection of a right-sided pituitary mass. Postoperatively, she developed clinical symptoms suggestive of adrenal insufficiency and a nadir cortisol level of 1.6 μg/dl on postoperative day 3, and hydrocortisone therapy was initiated. Permanent histopathology specimens showed Crooke’s hyaline change and ACTH-positive cells suggestive of an adenoma.

MRI at 7 T may be beneficial in identifying pituitary microadenoma location in cases of standard 1.5-T and 3-T MRI-negative Cushing’s disease. In the future, 7-T MRI may preempt inferior petrosal sinus sampling and help in cases of standard and dynamic contrast 1.5-T and 3-T MRI-negative Cushing’s disease.
Laser interstitial thermal therapy of the spine: technical aspects
Authors: Moussazadeh Nelson , Evans Linton T. , Grasu Roxana , Rhines Laurence D. , Tatsui Claudio E.
Published: March 2018

Spinal laser interstitial thermal therapy has been developed as a minimally invasive modality to treat epidural spinal tumors percutaneously. The safe and effective use of this technology requires meticulous preoperative trajectory planning and an intraoperative workflow incorporating navigation and MR thermography. Instrumented stabilization can be performed during the same operation if needed. Operative considerations and technical aspects are reviewed.

The video can be found here: https://youtu.be/P--frsag6gU.
Laser interstitial thermal therapy for an eloquent region supratentorial brain lesion
Authors: Sharma Mayur , Krivosheya Daria , Borghei-Razavi Hamid , Barnett Gene H. , Mohammadi Alireza M.
Published: March 2018

Laser interstitial thermal therapy (LITT) is a minimally invasive stereotactic technique that causes tumor ablation using thermal energy. LITT has shown to be efficacious for the treatment of deep-seated brain lesions, including those near eloquent areas. In this video, the authors present the case of a 62-year-old man with a history of metastatic melanoma who presented with worsening right-sided hemiparesis. MRI revealed a contrast-enhancing lesion in left centrum semiovale in close proximity to corticospinal tracts, consistent with radiation necrosis. The authors review their stepwise technique of LITT with special attention to details for a lesion located near eloquent area.

The video can be found here: https://youtu.be/ndrTgi6MXqE.
Contemporaneous biopsy and laser interstitial thermal therapy for two treatment-refractory brain metastases
Authors: Shah Ashish H. , Richardson Angela M. , Burks Joshua D. , Komotar Ricardo J.
Published: March 2018

Recurrent treatment-refractory brain metastases can be treated with modern adjuvant therapies such as laser interstitial thermal therapy (LITT). Since previously radiated lesions may be indolent (treatment effect) or recurrent tumor, histological confirmation may be helpful. The authors present the utility of contemporaneous biopsy and LITT using intraoperative O-arm navigation in a patient who presented with multiple refractory metastases. The authors demonstrate the utility of O-arm navigation to confirm intraoperative biopsy and LITT placement. Concurrent stereotactic biopsy and LITT may be a safe and efficacious method for both the diagnosis and treatment of deep lesions that are unamenable to standard adjuvant treatment modalities.

The video can be found here: https://youtu.be/SUY-qiahMyo.
Efficacy of an experimental propylene glycol-based, water-free caries detecting dye in comparison with Snoop® using histological analysis
Authors: Iranparvar Parastoo , Tabari Kasra , Shahi Anahita
Published: March 2018

Background and Aim: One limitation of caries disclosing dyes is the risk of sound dentin removal. This study sought to assess the efficacy of a newly developed experimental caries disclosing dye in complete removal of infected dentin and its properties in comparison with Snoop caries detecting dye using histological analysis.Materials and Methods: A caries detecting dye with improved properties was experimentally prepared. Twenty permanent teeth with occlusal caries were selected and divided into two groups of staining with the experimental dye (group 1) and Snoop caries detecting dye (group 2). Stained carious dentin was removed and the process of staining and caries removal was repeated until no staining was observed. DIAGNOdent laser caries detection aid was used in all cavities to ensure absence of caries. After decalcification, 5 sections were made of each tooth, Gram-stained and subjected to histological analysis. Presence of bacteria in the two groups following staining with the experimental and Snoop dyes was evaluated and statistically analyzed using Fisher’s exact test.Results: In the Snoop group, bacteria were present in 3 out of 50 (6.0%) specimens. In the experimental group, bacteria were found in 2 out of 60 specimens (4.0%). Fisher’s exact test showed no significant difference in this respect between the two groups.Conclusion: Histological analysis revealed similar efficacy of Snoop and the experimental caries detecting dyes in terms of complete elimination of infected dentin. Considering the improved properties of the experimental caries detecting dye, it may have superior efficacy in preventing unnecessary removal of sound dentin.Bangladesh Journal of Medical Science Vol.17(2) 2018 p.218-223
Handmade endoloop knotting technique without knot pusher for appendicular stump closure in laparoscopic appendectomy- personal experience
Authors: Iqbal Sajid , Malhotra Mohinder Kumar , Singh Majhail , Tabassum Saima
Published: March 2018

Aim: to devises a handmade endoloop knotting technique without the use of knot pusher thereby reducing the overall cost of laparoscopic appendectomy.Material and methods: This prospective study was conducted in MMIMSR Ambala from January 2015 to august 2017. All operations were performed by the same surgical team. Mesoappendix was coagulated with bipolar cautery and cut with scissors. Two handmade Meltzer loops were placed on base of appendix and tightened using conventionalgraspers.Results: 53 patients were included in the study. The time spent for preparing and tyingone loop was approximately 20-25 seconds. None of the patients had leakage from the appendicular stump. Only one polyglactin suture was used to make three loops. Knot pusher was not used in any of the patients.Conclusion: handmade endoloop used in this prospective study for securing appendicular stump using conventional laparoscopic graspers was found to be equally safe and can be easily mastered by any laparoscopic surgeon, which will reduce his dependency upon preformed endoloops making the procedure cost effective.Bangladesh Journal of Medical Science Vol.17(2) 2018 p.255-257
Extraction of Antioxidant Phenolic Compounds from Brewer’s Spent Grain: Optimization and Kinetics Modeling
Authors: Carciochi Ramiro , Sologubik Carlos , Fernández María , Manrique Guillermo , D’Alessandro Leandro
Published: March 2018

The kinetics of polyphenol extraction from brewer’s spent grain (BSG), using a batch system, ultrasound assistance, and microwave assistance and the evolution of antioxidant capacity of these extracts over time, were studied. The main parameters of extraction employed in the batch system were evaluated, and, by applying response surface analysis, the following optimal conditions were obtained: Liquid/solid ratio of 30:1 mL/g at 80 °C, using 72% (v/v) ethanol:water as the solvent system. Under these optimized conditions, ultrasound assistance demonstrated the highest extraction rate and equilibrium yield, as well as shortest extraction times, followed by microwave assistance. Among the mathematical models used, Patricelli’s model proved the most suitable for describing the extraction kinetics for each method tested, and is therefore able to predict the response values and estimate the extraction rates and potential maximum yields in each case.
A Stability Analysis on Mixed Convection Boundary Layer Flow along a Permeable Vertical Cylinder in a Porous Medium Filled with a Nanofluid and Thermal Radiation
Authors: Abu Bakar Shahirah , Arifin Norihan , Md Ali Fadzilah , Bachok Norfifah , Nazar Roslinda , Pop Ioan
Published: March 2018

A study on mixed convection boundary layer flow with thermal radiation and nanofluid over a permeable vertical cylinder lodged in a porous medium is performed in this current research by considering groupings of a variety nanoparticles, consisting of copper (Cu), aluminium (Al2O3) and titanium (TiO2). By using a method of similarity transformation, a governing set of ordinary differential equations has been reduced from the governing system of nonlinear partial differential equations, which are the values of selected parameters such as mixed convection parameter λ , nanoparticle volume fraction φ , radiation parameter Rd, suction parameter S, and curvature parameter ξ are solved numerically. From the numerical results, we observed that the involving of certain parameters ranges lead to the two different branches of solutions. We then performed a stability analysis by a bvp4c function (boundary value problem with fourth-order accuracy) to determine the most stable solution between these dual branches and the respective solutions. The features have been discussed in detail.
High-Performance Asymmetric Supercapacitors Based on the Surfactant/Ionic Liquid Complex Intercalated Reduced Graphene Oxide Composites
Authors: Lin Jun-Hong , Shi Bo-Wen , Chen Zhao-Cheng
Published: March 2018

In this paper, ionic surfactants are employed to intercalate thermally-reduced graphene oxide (TRG). The ionic interaction between the intercalated surfactant and the ionic liquid could lead to the formation of large-sized ionic aggregates and, hence, enlarge the interlayer distance between the TRG sheets. The morphology and vibration modes of these composites were systematically characterized using XRD (X-ray diffraction), SAXS (small-angle X-ray scattering), and FTIR (Fourier transform infrared spectroscopy). An asymmetric supercapacitor, which consisted of a cationic surfactant-intercalated electrode on one side and an anionic surfactant-intercalated electrode on the other, was examined. It was found that, with the increased interlayer distance, the energy density and capacitance of the cells were improved. It seems that the cell with a cationic surfactant as the cathode had the best energy density of 67.8 Wh/kg, which is 4.4-fold higher than that of the TRG cell.
Spatial Coherence of Backscattered Signals in Multi-Line Transmit Ultrasound Imaging and Its Effect on Short-Lag Filtered-Delay Multiply and Sum Beamforming
Authors: Matrone Giulia , Ramalli Alessandro
Published: March 2018

In Multi-Line Transmission (MLT), high frame-rate ultrasound imaging is achieved by the simultaneous transmission of multiple focused beams along different directions, which unfortunately generates unwanted artifacts in the image due to inter-beam crosstalk. The Filtered-Delay Multiply and Sum (F-DMAS) beamformer, a non-linear spatial-coherence (SC)-based algorithm, was demonstrated to successfully reduce such artifacts, improving the spatial resolution at the same time. In this paper, we aim to provide further insights on the working principle and performance of F-DMAS beamforming in MLT imaging. First, we carry out an analytical study to analyze the behavior and trend of backscattered signals SC in MLT images, when the number of simultaneously transmitted beams and/or their angular spacing change. We then reconsider the F-DMAS algorithm proposing the “short-lag F-DMAS” formulation, in order to limit the maximum lag of signals used for the SC computation on which the beamformer is based. Therefore, we investigate in simulations how the performance of short-lag F-DMAS varies along with the maximum lag in the different MLT configurations considered. Finally, we establish a relation between the obtained results and the signals SC trend.
Variability and Factors of Influence of Extreme Wet and Dry Events in Northern Mexico
Authors: Llanes-Cárdenas Omar , Gaxiola-Hernández Alberto , Estrella-Gastelum Rosa , Norzagaray-Campos Mariano , Troyo-Diéguez Enrique , Pérez-González Ernestina , Ruiz-Guerrero Rosario , De J. Pellegrini Cervantes Manuel
Published: March 2018

The goal of this study was to generate a method to examine seasonal variability by climatic classification and Pacific seasonal factors to identify extreme wet and dry events in northern Mexico for the period 1952–2013. Using the standardized precipitation and evapotranspiration index (SPEI) on scales of three months (SPEI-3) and 24 months (SPEI-24), the variability of extreme wet and dry events were measured. The SPEI-3 and SPEI-24 anomalies were divided by the standard deviation (standardized Z anomalies). A Pearson correlation for SPEI-3, SPEI-24, Pacific decadal oscillation (PDO) and the oceanic El Niño index (ONI) was applied. Wet extreme events were recorded in 1954, 1968, 1976–1977, 1981, 1984, 1986 and 2003, of which the greatest magnitude was recorded in 1984 for the Sinaloa-very dry region. Extreme dry events were recorded in 1952–1953, 1990, 1997, 2003 and 2011–2013. The Z anomalies of the wet extreme events observed coincide with +PDO phase anomalies. In this study, the El Niño southern oscillation (ENSO) has little influence on wet and dry extreme events in northern Mexico. The negative phase anomalies of sea surface temperature (−SST) in the equatorial and eastern Pacific are indicators of extreme wet events. This study shows for the first time the influence of the PDO and the ONI on seasonal variability of extreme wet and dry events by climatic classification through the SPEI index in northern Mexico.
Pharmacological Activities of Phytomedicines: A Challenge Horizon for Rational Knowledge
Authors: Rodríguez Villanueva Javier , Martín Esteban Jorge , Rodríguez Villanueva Laura
Published: March 2018

Herbal drugs have been widely used throughout the course of history. Traditional knowledge based on religious beliefs and/or experience has been transmitted orally between generations. First attempts to provide scientific evidence came in the 19th century when potent compounds were first isolated. Since then, modern pharmacology theory has been assumed by phytotherapy. Scientists have tried to elucidate the molecular mechanism of each compound and, for a pharmacological indication, propose an effective and secure dose. Stepwise, clinical trials confirm the benefits of herbal drug use in therapeutics, especially for chronic diseases. However, herbal drugs exert pleiotropic effects, and there is still a need for a complete, rational, and widely accepted theory that can explain phytotherapy efficacy. The “-omics” might help with this matter. Studies of modification in the gene expression profile, the metabolome, and the physiopathological state after the administration of a herbal extract could provide relevant information that verifies herbal therapies.
Effects of Short-Chain n-Alcohols on the Properties of Asphaltenes at Toluene/Air and Toluene/Water Interfaces
Authors: Martins Raphael , Martins Lilian , Santos Ronaldo
Published: March 2018

Crude oil asphaltenes contain a wide series of chemical species, which includes the most polar compounds and interfacially active agents from the petroleum. Asphaltenes have been considered to be implicated in foam and emulsion formation during the petroleum recovery and production process. In this work, the interfacial activity of organic solutions containing asphaltene and n-alcohols was investigated. Asphaltene extraction from a 28°API crude oil produced 2.5 wt % of n-pentane precipitated asphaltene (C5I). Dynamic surface and interfacial tensions of asphaltene solutions were assessed by the pendant drop method. Asphaltene films were evaluated at the air-water interface using a Langmuir trough. Results were expressed by means of the interfacial tension time-dependence. Interfacial tension measurements showed alcohols reduce the toluene/water interfacial tension of asphaltene solutions. The interfacial tension was reduced from 23 mN/m to 15.5 mN/m for a 2 g/L solution of asphaltene plus n-butanol. Higher asphaltene concentrations did not affect the toluene/air surface tension. The effects of n-alcohols on the asphaltene surface activity was dependent on the asphaltene aggregation state. n-Alcohols modify the asphaltene film elasticity and the film phase behavior.
Comprehensive Evaluation of Coal-Fired Power Units Using Grey Relational Analysis and a Hybrid Entropy-Based Weighting Method
Authors: Wu Dianfa , Wang Ningling , Yang Zhiping , Li Chengzhou , Yang Yongping
Published: March 2018

In recent years, coal-fired power plants contribute the biggest part of power generation in China. Challenges of energy conservation and emission reduction of the coal-fired power plant encountering with a rapid growth due to the rising proportion of renewable energy generation in total power generation. Energy saving power generation dispatch (ESPGD) based on power units sorting technology is a promising approach to meet the challenge. Therefore, it is crucial to establish a reasonable and feasible multi-index comprehensive evaluation (MICE) framework for assessing the performance of coal-fired power units accessed by the power grid. In this paper, a hierarchical multiple criteria evaluation system was established. Except for the typical economic and environmental indices, the evaluation system considering operational flexibility and power quality indices either. A hybrid comprehensive evaluation model was proposed to assess the unit operational performance. The model is an integration of grey relational analysis (GRA) with analytic hierarchy process (AHP) and a novel entropy-based method (abbreviate as BECC) which integrates bootstrap method and correlation coefficient (CC) into entropy principle to get the objective weight of indices. Then a case study on seven typical 600 megawatts coal-fired power units was carried out to illustrate the proposed evaluation model, and a weight sensitivity analysis was developed in addition. The results of the case study shows that unit 4 has the power generating priority over the rest ones, and unit 2 ranks last, with the lowest grey relational degree. The weight sensitivity analysis shows that the environmental factor has the biggest sensitivity coefficient. And the validation analysis of the developed BECC weight method shows that it is feasible for the MICE model, and it is stable with an ignorable uncertainty caused by the stochastic factor in the bootstrapping process. The elaborate analysis of the result reveals that it is feasible to rank power units with the proposed evaluation model. Furthermore, it is beneficial to synthesize the updated multiple criteria in optimizing the power generating priority of coal-fired power units.
Design and Experiment Analysis of a Direct-Drive Wave Energy Converter with a Linear Generator
Authors: Zhang Jing , Yu Haitao , Shi Zhenchuan
Published: March 2018

Coastal waves are an abundant nonpolluting and renewable energy source. A wave energy converter (WEC) must be designed for efficient and steady operation in highly energetic ocean environments. A direct-drive wave energy conversion (D-DWEC) system with a tubular permanent magnet linear generator (TPMLG) on a wind and solar photovoltaic complementary energy generation platform is proposed to improve the conversion efficiency and reduce the complexity and device volume of WECs. The operating principle of D-DWECs is introduced, and detailed analyses of the proposed D-DWEC’s floater system, wave force characteristics, and conversion efficiency conducted using computational fluid dynamics are presented. A TPMLG with an asymmetric slot structure is designed to increase the output electric power, and detailed analyses of the magnetic field distribution, detent force characteristics, and no-load and load performances conducted using finite element analysis are discussed. The TPMLG with an asymmetric slot, which produces the same power as the TPMLG with a symmetric slot, has one fifth detent force of the latter. An experiment system with a prototype of the TPMLG with a symmetric slot is used to test the simulation results. The experiment and analysis results agree well. Therefore, the proposed D-DWEC fulfills the requirements of WEC systems.
Evaluation of Tree Species for Biomass Energy Production in Northwest Spain
Authors: Álvarez-Álvarez Pedro , Pizarro Consuelo , Barrio-Anta Marcos , Cámara-Obregón Asunción , Bueno Julio , Álvarez Ana , Gutiérrez Inés , Burslem David
Published: March 2018

Three types of forest stands (chestnut coppice, maritime pine stands, and poplar and willow short-rotation woody crops (SRWC)) were evaluated to determine their potential for energy production. The properties of the main aboveground biomass fractions (wood, bark and crown) and also the whole tree were analysed, thus providing data that could be used for management purposes and for evaluating potential forest, biomass energy yields and atmospheric emissions. Proximate, elemental and energetic analyses of the biomass provided important information for evaluating the fuel potential. The energetic value of the biomass derived from the maritime pine stands was higher than that of the poplar and willow clonal stands and chestnut coppice stands. The high ash content of the chestnut bark, relative to that of the wood and crown material, is also an important consideration in relation to energy production. The proportion of carbon concentration accumulated per tree was very similar in all types of material studied, although the N and S contents were higher in the maritime pine stands than in the other stands. For this reason, selection of species and fractions can help to improve fuel quality and the efficiency of the combustion processes, and to minimize atmospheric emissions.
Forest Above-Ground Biomass Estimation Using Single-Baseline Polarization Coherence Tomography with P-Band PolInSAR Data
Authors: Zhang Haibo , Wang Changcheng , Zhu Jianjun , Fu Haiqiang , Xie Qinghua , Shen Peng
Published: March 2018

Forest above ground biomass (AGB) extraction using Synthetic Aperture Radar (SAR) images has been widely used in global carbon cycle research. Classical AGB inversion methods using SAR images are mainly based on backscattering coefficients. The polarization coherence tomography (PCT) technology which can generate vertical profiles of forest relative reflectivity, has the potential to improve the accuracy of biomass inversion. The relationship between vertical profiles and forest AGB is modeled by some parameters defined based on geometric characteristics of the relative reflectivity distribution curve. But these parameters are defined without physical characteristics. Among these parameters, tomographic height (TomoH) is considered as the most important one. However, TomoH only corresponds to the highest volume relative reflectivity, which is lower than the actual forest height, affecting the accuracy of forest height and AGB inversion. In this paper, we introduce a new parameter, the canopy height (Hac), for AGB inversion by analyzing the vertical backscatter power loss. Then, we construct an inversion model based on the combination of the new parameter (Hac) and other parameters from the tomographic profile. The P-band polarimetric SAR datasets of the European Space Agency (ESA) BioSAR 2008 campaign acquired over Krycklan Catchment are selected for the verification experiment at two different flight directions. The results show that Hac performs better in estimating forest height and AGB than TomoH does. The inversion root mean square error (RMSE) of the proposed method is 18.325 t ha−1, and the result of using TomoH is 21.126 t ha−1.
Real-Time Estimation of Population Exposure to PM2.5 Using Mobile- and Station-Based Big Data
Authors: Chen Bin , Song Yimeng , Jiang Tingting , Chen Ziyue , Huang Bo , Xu Bing
Published: March 2018

Extremely high fine particulate matter (PM2.5) concentration has been a topic of special concern in recent years because of its important and sensitive relation with health risks. However, many previous PM2.5 exposure assessments have practical limitations, due to the assumption that population distribution or air pollution levels are spatially stationary and temporally constant and people move within regions of generally the same air quality throughout a day or other time periods. To deal with this challenge, we propose a novel method to achieve the real-time estimation of population exposure to PM2.5 in China by integrating mobile-phone locating-request (MPL) big data and station-based PM2.5 observations. Nationwide experiments show that the proposed method can yield the estimation of population exposure to PM2.5 concentrations and cumulative inhaled PM2.5 masses with a 3-h updating frequency. Compared with the census-based method, it introduced the dynamics of population distribution into the exposure estimation, thereby providing an improved way to better assess the population exposure to PM2.5 at different temporal scales. Additionally, the proposed method and dataset can be easily extended to estimate other ambient pollutant exposures such as PM10, O3, SO2, and NO2, and may hold potential utilities in supporting the environmental exposure assessment and related policy-driven environmental actions.
The Association between Potential Exposure to Magazine Ads with Voluntary Health Warnings and the Perceived Harmfulness of Electronic Nicotine Delivery Systems (ENDS)
Authors: Shang Ce , Weaver Scott , Zahra Nahleen , Huang Jidong , Cheng Kai-Wen , Chaloupka Frank
Published: March 2018

(1) Background: Several brands of electronic nicotine delivery systems (ENDS) carry voluntary health warning messages. This study examined how potential exposure to ENDS magazine ads with these voluntary health warnings were associated with the perceived harmfulness of ENDS. (2) Methods: Risk perception measures and self-reported exposure to ENDS ads were obtained from the 2014 Georgia State University (GSU) Tobacco Products and Risk Perceptions Survey of a nationally representative sample of U.S. adults. We examined the association between potential exposure to magazine ads with warnings and the perceived harms of ENDS relative to cigarettes, using binary logistic regressions and controlling for general ENDS ad exposure and socio-demographic characteristics. (3) Results: Potential exposure to ENDS magazine ads with warnings was associated with a lower probability of considering ENDS to be more or equally harmful compared to cigarettes, particularly among non-smokers (OR = 0.16; 95% CI: 0.04–0.77). In addition, ad exposure, ENDS use history, race/ethnicity, gender, education, and income were also associated with harm perceptions. (4) Conclusions: This study did not find evidence that magazine ads with warnings increased misperceptions that ENDS are equally or more harmful than cigarettes. With more ENDS advertisements carrying warnings, more research is needed to determine how the warnings in advertisements convey relative harm information to consumers and the public.
Assessment of Potentially Toxic Elements as Non-Point Sources of Contamination in the Upper Crocodile Catchment Area, North-West Province, South Africa
Authors: Nde Samuel , Mathuthu Manny
Published: March 2018

The concentration of potential toxic elements (PTEs) in the Upper Crocodile river catchment area in North-west Province, South Africa, was investigated. Water and sediment samples were collected among different land uses in the upper Crocodile River catchment area and analysed using inductively-coupled plasma–mass spectrometry (ICP–MS). Several guidelines were used to gauge the level of contamination and possible toxic effect of PTEs. The physicochemical analysis showed that electrical conductivity (EC), pH, and total dissolved solids (TDS) values complied with the recommended values of Department of Water and Forestry (DWAF) guidelines for South Africa. The average concentration of Cu, Pb, Cd, Zn, As, Cr, Al, and Mn in the water samples were lower than the recommended levels for water-quality guidelines for aquatic environments except for Fe, which exceeded the recommended values of DWAF of 0.1 mg/L and EPA (US) of 0.3 mg/L. The level of contamination was measured using the enrichment factor, contamination factor, and geoaccumulation index. The level of Cr was above the stipulated threshold limit of the sediment quality guideline for adverse biological effects, suggesting an ecotoxicology risk of anthropogenic origin, which was confirmed by statistical analysis. The non-point sources of PTEs are spatially distributed according to land-use types and are strongly correlated to land use.
Investigating the Effect of Personality, Internet Literacy, and Use Expectancies in Internet-Use Disorder: A Comparative Study between China and Germany
Authors: Stodt Benjamin , Brand Matthias , Sindermann Cornelia , Wegmann Elisa , Li Mei , Zhou Min , Sha Peng , Montag Christian
Published: March 2018

Research on Internet-use Disorder (IUD) has increased rapidly, indicating its clinical and global importance. Past studies suggested cultural diversity regarding the prevalence of an IUD, e.g., between Asian and European countries. Additionally, it was found that personality factors, Internet-related cognitions and specific competences seem to influence IUD tendencies, but research lacks in cultural comparative studies regarding these mechanisms. This study focuses on differences between Germany and China regarding the above-mentioned characteristics. German (n = 411; M = 20.70 years, SD = 3.34 years) and Chinese participants (n = 410; M = 20.72 years, SD = 2.65 years) answered the short Internet Addiction Test, Big Five Inventories, the Internet-use Expectancies Scale, as well as the Internet Literacy Questionnaire. The results revealed higher occurrence of IUD symptoms in China. Furthermore, Chinese participants scored significantly higher on neuroticism and agreeableness, whereas German participants scored higher on extraversion and openness. Compared to German participants, Chinese showed higher expectancies to avoid negative feelings online and to be positively reinforced. Regarding Internet literacy, German participants indicated higher skills concerning the reflection and critical analysis of online content, whereas Chinese showed higher expertise in producing and interacting online. Further, simple slope analyses indicated that certain Internet literacy domains were related differentially to IUD symptoms in Germany and China. While Chinese participants with higher reflective skills indicated highest IUD symptoms, reflective skills revealed no effect in Germany. Additionally, higher self-regulative skills correlated with lower IUD symptoms in the German, but not in the Chinese sample. The results give a hint to potential cultural differences regarding IUD, especially on the predictive and protective role of Internet literacy domains.
Branched Chain Amino Acids: Beyond Nutrition Metabolism
Authors: Nie Cunxi , He Ting , Zhang Wenju , Zhang Guolong , Ma Xi
Published: March 2018

Branched chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile), and valine (Val), play critical roles in the regulation of energy homeostasis, nutrition metabolism, gut health, immunity and disease in humans and animals. As the most abundant of essential amino acids (EAAs), BCAAs are not only the substrates for synthesis of nitrogenous compounds, they also serve as signaling molecules regulating metabolism of glucose, lipid, and protein synthesis, intestinal health, and immunity via special signaling network, especially phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signal pathway. Current evidence supports BCAAs and their derivatives as the potential biomarkers of diseases such as insulin resistance (IR), type 2 diabetes mellitus (T2DM), cancer, and cardiovascular diseases (CVDs). These diseases are closely associated with catabolism and balance of BCAAs. Hence, optimizing dietary BCAA levels should have a positive effect on the parameters associated with health and diseases. This review focuses on recent findings of BCAAs in metabolic pathways and regulation, and underlying the relationship of BCAAs to related disease processes.
Angiotensin II-Induced Mesangial Cell Damage Is Preceded by Cell Membrane Permeabilization Due to Upregulation of Non-Selective Channels
Authors: Gómez Gonzalo , Fernández Paola , Velarde Victoria , Sáez Juan
Published: March 2018

Connexin43 (Cx43), pannexin1 (Panx1) and P2X7 receptor (P2X7R) are expressed in kidneys and are known to constitute a feedforward mechanism leading to inflammation in other tissues. However, the possible functional relationship between these membrane channels and their role in damaged renal cells remain unknown. In the present work, we found that MES-13 cells, from a cell line derived from mesangial cells, stimulated with angiotensin II (AngII) developed oxidative stress (OS, thiobarbituric acid reactive species (TBARS) and generated pro-inflammatory cytokines (ELISA; IL-1β and TNF-α). The membrane permeability increased progressively several hours before the latter outcome, which was a response prevented by Losartan, indicating the involvement of AT1 receptors. Western blot analysis showed that the amount of phosphorylated MYPT (a substrate of RhoA/ROCK) and Cx43 increased progressively and in parallel in cells treated with AngII, a response followed by an increase in the amount in Panx1 and P2X7R. Greater membrane permeability was partially explained by opening of Cx43 hemichannels (Cx43 HCs) and Panx1 channels (Panx1 Chs), as well as P2X7Rs activation by extracellular ATP, which was presumably released via Cx HCs and Panx1 Chs. Additionally, inhibition of RhoA/ROCK blocked the progressive increase in membrane permeability, and the remaining response was explained by the other non-selective channels. The rise of activity in the RhoA/ROCK-dependent pathway, as well as in Cx HCs, P2X7R, and to a minor extent in Panx1 Chs led to higher amounts of TBARS and pro-inflammatory cytokines. We propose that AngII-induced mesangial cell damage could be effectively inhibited by concomitantly inhibiting the RhoA/ROCK-dependent pathway and one or more non-selective channel(s) activated through this pathway.
Micro-Economics of Apoptosis in Cancer: ncRNAs Modulation of BCL-2 Family Members
Authors: Villanova Lidia , Careccia Silvia , De Maria Ruggero , Fiori Micol
Published: March 2018

In the last few years, non-coding RNAs (ncRNAs) have been a hot topic in cancer research. Many ncRNAs were found to regulate the apoptotic process and to play a role in tumor cell resistance to treatment. The apoptotic program is on the frontline as self-defense from cancer onset, and evasion of apoptosis has been classified as one of the hallmarks of cancer responsible for therapy failure. The B-cell lymphoma 2 (BCL-2) family members are key players in the regulation of apoptosis and mediate the activation of the mitochondrial death machinery in response to radiation, chemotherapeutic agents and many targeted therapeutics. The balance between the pro-survival and the pro-apoptotic BCL-2 proteins is strictly controlled by ncRNAs. Here, we highlight the most common mechanisms exerted by microRNAs, long non-coding RNAs and circular RNAs on the main mediators of the intrinsic apoptotic cascade with particular focus on their significance in cancer biology.
A Whole Germline BRCA2 Gene Deletion: How to Learn from CNV In Silico Analysis
Authors: Scaglione Giovanni , Concolino Paola , De Bonis Maria , De Paolis Elisa , Minucci Angelo , Ferrandina Gabriella , Scambia Giovanni , Capoluongo Ettore
Published: March 2018

BRCA1/2 screening in Hereditary Breast and Ovarian Syndrome (HBOC) is an essential step for effective patients’ management. Next-Generation Sequencing (NGS) can rapidly provide high throughput and reliable information about the qualitative and quantitative status of tumor-associated genes. Straightforwardly, bioinformatics methods play a key role in molecular diagnostics pipelines. BRCA1/2 genes were evaluated with our NGS workflow, coupled with Multiplex Amplicon Quantification (MAQ) and Multiplex Ligation-dependent Probe Amplification (MLPA) assays. Variant calling was performed on Amplicon Suite, while Copy Number Variant (CNV) prediction by in house and commercial CNV tools, before confirmatory MAQ/MLPA testing. The germline profile of BRCA genes revealed a unique HBOC pattern. Although variant calling analysis pinpointed heterozygote and homozygote polymorphisms on BRCA1 and BRCA2, respectively, the CNV predicted by our script suggested two conflicting interpretations: BRCA1 duplication and/or BRCA2 deletion. Our commercial software reported a BRCA1 duplication, in contrast with variant calling results. Finally, the MAQ/MLPA assays assessed a whole BRCA2 copy loss. In silico CNV analysis is a time and cost-saving procedure to powerfully identify possible Large Rearrangements using robust and efficient NGS pipelines. Our layout shows as bioinformatics algorithms alone cannot completely and correctly identify whole BRCA1/2 deletions/duplications. In particular, the complete deletion of an entire gene, like in our case, cannot be solved without alternative strategies as MLPA/MAQ. These findings support the crucial role of bioinformatics in deciphering pitfalls within NGS data analysis.
State-of-the-Art Fluorescence Fluctuation-Based Spectroscopic Techniques for the Study of Protein Aggregation
Authors: Kitamura Akira , Kinjo Masataka
Published: March 2018

Neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease, are devastating proteinopathies with misfolded protein aggregates accumulating in neuronal cells. Inclusion bodies of protein aggregates are frequently observed in the neuronal cells of patients. Investigation of the underlying causes of neurodegeneration requires the establishment and selection of appropriate methodologies for detailed investigation of the state and conformation of protein aggregates. In the current review, we present an overview of the principles and application of several methodologies used for the elucidation of protein aggregation, specifically ones based on determination of fluctuations of fluorescence. The discussed methods include fluorescence correlation spectroscopy (FCS), imaging FCS, image correlation spectroscopy (ICS), photobleaching ICS (pbICS), number and brightness (N&B) analysis, super-resolution optical fluctuation imaging (SOFI), and transient state (TRAST) monitoring spectroscopy. Some of these methodologies are classical protein aggregation analyses, while others are not yet widely used. Collectively, the methods presented here should help the future development of research not only into protein aggregation but also neurodegenerative diseases.