bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrate removal by nitrate-dependent Fe(II) oxidation in an upflow denitrifying biofilm reactor
Authors: Zhou Jun , Wang Hongyu , Yang Kai , Sun Yuchong , Tian Jun
Published: July 2015

A continuous upflow biofilm reactor packed with ceramsite was constructed for nitrate removal under an anaerobic atmosphere without an organic carbon source. Denitrifying bacteria, Pseudomonas sp. W1, Pseudomonas sp. W2 and Microbacterium sp. W5, were added to the bioreactor as inocula. Nitrate concentration, nitrite accumulation and nitrogen removal efficiency in the effluent were investigated under various conditions set by several parameters including pH, hydraulic retention time (HRT), ratios of carbon to nitrogen (C/N) and temperature. The results illustrated that the maximum removal efficiency of nitrogen was 85.39%, under optimum reaction parameters, approximately pH 6.5–7, HRT = 48 hours and C/N = 13.1:1 at temperature of 30 °C, which were determined by experiment.
Conversion of sewage sludge to commodity chemicals via syngas fermentation
Authors: Ganigué Ramon , Ramió-Pujol Sara , Sánchez Patricia , Bañeras Lluís , Colprim Jesús
Published: July 2015

Gasification of sewage sludge allows the recovery of energy, and produces a mix of CO, CO2 and H2 called synthesis gas (or syngas), which can be fermented by acetogenic bacteria to added-value products. This work presents the conversion of syngas to organic acids and alcohols using both pure and mixed cultures. Pure culture kinetic experiments with Clostridium carboxidivorans P7 resulted in the production of high concentrations of acetate (454 mgC/L) and ethanol (167 mgC/L). The pH was the main factor driving solventogenesis, with about 50% of the products in the form of alcohols at pH 5. Conversely, laboratory-scale experiments using a carboxydotrophic mixed culture of the genus Clostridium enriched from anaerobic digester sludge of a municipal wastewater treatment plant was capable of producing mainly butyrate, with maximum concentration of 1,184 mgC/L.
Vanadium(V) removal from aqueous solution and real wastewater using quaternized pine sawdust
Authors: Leiviskä T. , Keränen A. , Vainionpää N. , Al Amir J. , Hormi O. , Tanskanen J.
Published: July 2015

Cross-linked and quaternized pine sawdust was tested for vanadium removal from a synthetic aqueous solution as well as from real industrial wastewater which had a considerable amount of vanadium and other ions such as sulphate, ammonium and nickel. The maximum vanadium sorption capacity of the modified pine sawdust was found to be 130 mg/g in synthetic solution and 103 mg/g in real wastewater. Modified pine sawdust worked well over a wide range of pH. Column studies with real wastewater proved that vanadium was efficiently desorbed from the material with 2 M NaOH and that the material could be reused.
Removal and transformation products of ibuprofen obtained during ozone- and ultrasound-based oxidative treatment
Authors: Yargeau Viviane , Danylo Félix
Published: July 2015

The oxidation of ibuprofen (IBP) in water was evaluated using oxidative treatments: ozonation, sonication, hydrogen peroxide addition and combinations of these processes. After 20 minutes of treatment, ozone coupled with hydrogen peroxide at pH 7, 15 °C, an ozone dose of 16 mg/L and a hydrogen peroxide concentration of 7.1 mg/L was found to have the highest IBP (95%) and chemical oxygen demand (COD) (41%) removals. A synergistic effect was observed for the combined ozonation/sonication process, which might be explained by an improved mass transfer of ozone in the solution due to the presence of ultrasonic pressure waves. Transformation products were detected in the treated solutions. The nature of five of these products was confirmed by liquid chromatography–mass spectrometry (LC-MS), including 4-isobutylacetophenone (4-IBAP), oxo-IBP, 4-acetylbenzoic acid, 4-ethybenzaldehyde and oxalic acid. In addition, COD analyses for each experiment showed that the ratio of %COD removal to %IBP removal was highest with sonication; suggesting that this oxidative process offers other mechanisms of removal which may lead to further degradation of products formed. This study presents the first data on removal of IBP by sonication coupled to ozonation and provides some insight into the potential of this combined treatment approach for the removal of contaminants of emerging concern.
Magnesium ions improving the growth and organics reduction of Rhodospirillum rubrum cultivated in sewage through regulating energy metabolism pathways
Authors: Xu Chang-Ru , Wu Pan , Lang Lang , Liu Ri-Jia , Li Jian-Zheng , Ji Yu-Bin
Published: July 2015

Rhodospirillum rubrum has the potential for biomass resource recycling combined with sewage purification. However, low biomass production and yield restricts the potential for sewage purification. This research investigated the improvement of biomass production, yield and organics reduction by Mg2+ in R. rubrum wastewater treatment. Results showed that with optimal dosage (120 mg/L), biomass production reached 4,000 mg/L, which was 1.5 times of that of the control group. Biomass yield was improved by 43.3%. Chemical oxygen demand (COD) removal reached over 90%. Hydraulic retention time was shortened by 25%. Mechanism analysis indicated that Mg2+ enhanced the isocitrate dehydrogenase and Ca2+/Mg2+-ATPase activities, bacteriochlorophyll content on respiration and photophosphorylation. These effects then enhanced ATP production, which led to more biomass accumulation and COD removal. With 120 mg/L Mg2+ dosage, the isocitrate dehydrogenase and Ca2+/Mg2+-ATPase activities, bacteriochlorophyll content, ATP production were improved, respectively, by 33.3%, 50%, 67%, 41.3% compared to those of the control group.
Relationship between serum biomarkers of cartilage and bone metabolism and joint injury in young Thoroughbred racehorses in training
Authors: Jackson Brendan F. , Reed Suzanne R. , Price Joanna S. , Verheyen Kristien L. P.
Published: July 2015

OBJECTIVE To compare serum concentrations of biomarkers of cartilage and bone metabolism between racehorses with a carpal or metacarpophalangeal or metatarsophalangeal (ie, fetlock) joint injury and matched uninjured control horses, determine changes in biomarker concentrations following joint injury, and establish the biomarkers’ diagnostic test performance.

ANIMALS 50 Thoroughbred racehorses with a carpal or fetlock joint injury and 50 matched uninjured horses (control horses).

PROCEDURES Serum concentrations of 2 cartilage synthesis biomarkers (carboxy-terminal propeptide of type II collagen [CPII] and chondroitin sulfate epitope 846 [CS846]), 2 cartilage degradation biomarkers (neoepitope generated by collagenase cleavage of type II collagen [C2C] and cross-linked carboxy-terminal telopeptide fragments of type II collagen [CTX-II]), and serum activity of a bone formation marker (bone-specific alkaline phosphatase [BAP]) were measured around the time of injury diagnosis and monthly thereafter for as long as possible.

RESULTS Injured horses as a group and horses specifically with fetlock joint injuries had significantly lower serum CPII concentrations and significantly higher serum BAP activities than matched control horses. Concentrations of CTX-II were decreased between 2 and 4 months following joint injury. Measurement of CPII concentration at baseline could distinguish between injured horses and control horses with a sensitivity of 82% and specificity of 50%.

CONCLUSIONS AND CLINICAL RELEVANCE Although significant differences in specific biomarker concentrations between horses with carpal and fetlock joint injuries and matched control horses were identified, there was no convincing evidence of the suitability of these biomarkers as diagnostic or prognostic tools in a clinical setting.
Dynamic computed tomographic determination of scan delay for use in performing cardiac angiography in clinically normal dogs
Authors: Kim Jisun , Bae Yeonho , Lee Gahyun , Jeon Sunghoon , Choi Jihye
Published: July 2015

OBJECTIVE To determine the scan delay for use in performing cardiac CT angiography in dogs.

ANIMALS 4 clinically normal adult Beagles.

PROCEDURES In a crossover study, 12 formulations of iohexol solutions differing in iodine dose (300, 400, and 800 mg/kg) and concentration (undiluted and diluted 1:1, 1:2, and 1:3 with saline [0.9% NaCl] solution) were administered IV to each dog. Dynamic CT angiography was performed to evaluate enhancement characteristics of each formulation, with the region of interest set over the aorta. Time-attenuation curves (TACs) were obtained and analyzed.

RESULTS Peak arc–type TACs were obtained after administration of all undiluted formulations. Curve shape changed from peak arc type to plateau type as the total volume of the contrast solution (ie, dilution) increased. Prolonged peaks characteristic of plateau-type TACs suggested that a sufficient period of homogeneous attenuation could be achieved for CT scanning with administration of higher iohexol dilutions (1:2 or 1:3) containing higher iodine doses (400 or 800 mg/kg). In particular, attenuation values for plateau-type TACs remained between 200 and 300 Hounsfield units for > 16 seconds after the plateau endpoint was reached for 1:2 and 1:3 dilutions containing an iodine dose of 800 mg/kg. Scan delays of 13 to 17 seconds were computed for those 2 formulations.

CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that for clinically normal dogs, a scan delay of 13 to 17 seconds could be used to perform cardiac CT angiography with iohexol solutions containing an iodine dose of 800 mg/kg at dilutions of 1:2 or 1:3.
Effects of various cardiovascular drugs on indices obtained with two-dimensional speckle tracking echocardiography of the left atrium and time–left atrial area curve analysis in healthy dogs
Authors: Osuga Tatsuyuki , Nakamura Kensuke , Morita Tomoya , Lim Sue Yee , Yokoyama Nozomu , Morishita Keitaro , Ohta Hiroshi , Takiguchi Mitsuyoshi
Published: July 2015

OBJECTIVE To evaluate the effects of dobutamine, esmolol, milrinone, and phenylephrine on left atrial phasic function of healthy dogs.

ANIMALS 9 healthy Beagles.

PROCEDURES Following sedation with propofol on each of 4 experimental days, dogs were administered a constant rate infusion of dobutamine (5 μg/kg/min), esmolol (500 μg/kg/min), milrinone (25 μg/kg, IV bolus, followed by 0.5 μg/kg/min), or phenylephrine (2 μg/kg/min). There was at least a 14-day interval between experimental days. Each drug was administered to 6 dogs. Conventional and 2-D speckle tracking echocardiography were performed before (baseline) and after administration of the cardiovascular drug, and time–left atrial area curves were derived to calculate indices for left atrial reservoir, conduit, and booster pump functions (left atrial phasic function) and left ventricular contractility and lusitropy.

RESULTS Compared with baseline values, indices for left atrial reservoir and booster pump functions and left ventricular contractility and lusitropy were significantly increased following dobutamine administration; indices for left atrial phasic function and left ventricular lusitropy were changed insignificantly, and indices for left ventricular contractility were significantly impaired following esmolol administration; indices for left atrial phasic function and left ventricular relaxation were changed insignificantly, and indices for left ventricular systolic function were significantly augmented following milrinone administration; and indices for left atrial phasic function and left ventricular lusitropy were changed insignificantly, and indices of ventricular contractility were significantly impaired following phenylephrine administration.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that, following administration of dobutamine, esmolol, milrinone, or phenylephrine to healthy dogs, left atrial phasic function indices were fairly stable and did not parallel changes in left ventricular function indices.
Discrimination of healthy versus sick steers by means of continuous remote monitoring of animal activity
Authors: Smith Jacqueline L. , Vanzant Eric S. , Carter Craig N. , Jackson Carney B.
Published: July 2015

OBJECTIVE To test a unique electronic ear tag designed to collect movement data to determine whether physical activity of sick steers differed from that of healthy steers.

ANIMALS 206 steers.

PROCEDURES Physical activity in 2 groups of steers during November and December of 2010 (101 steers; the tag of 1 steer failed, and thus that steer was removed from the study, which resulted in data for 100 steers) and 2011 (105 steers) was monitored with an electronic ear tag device with an on-board triple-axis accelerometer. The accelerometer recorded motion in all 3 axes in the form of counts per minute. A radio-frequency transmitter on the ear tag delivered serial packets of motion data to a local server. An algorithm was developed to analyze the activity data to determine whether this technique could be used to assess health status with high accuracy.

RESULTS Steers that became sick had significantly fewer activity counts (approx 25% fewer), compared with the activity counts of steers that remained healthy the entire time.

CONCLUSIONS AND CLINICAL RELEVANCE In this study, automated detection of health status in growing cattle was feasible through remote monitoring of animal activity. Early identification of sick animals should lead to improved health outcomes, increased marketability, and improved animal well-being and help to minimize the use of antimicrobials that could contribute to resistant bacteria.
Nominal KAŊ form in Basse Mandinka: Its cognitive mapping and taxonomical status (Part 2)
Authors: Andrason Alexander
Published: July 2015

Purpose: T he present study, divided into a series of two papers, provides a detailed empirical description and cognitive-grammaticalization analysis of the meaning of a Mandinka verbal expression compounded of the non-verbal predicator be ‘be’, a verbal noun expressing a given action and the postposition kaŋ ‘on, at’ (so-called the Nominal KAŊ form).

Method: T he author follows the cognitive approach to verbal semantics which consists first of determining the exact range of contextually induced senses and next of unifying such values into a consistent map based upon certain diachronic universals or grammaticalization paths.

Results: T he synchronic inventory of senses of the Nominal KAŊ form (i.e. progressive, continuous, progressive-iterative, iterative, habitual and durative values) shows that this construction can be mapped using the imperfective path as a template of chaining. This mapping, hypothesized on the ground of synchronic semantic evidence and typological diachronic laws, is next corroborated by the structural properties of the Nominal KAŊ locution, especially by its locative and nominal character.

Conclusion: A ll the evidence enables the author to semantically define the NomKAŊ form as a nonadvanced imperfective-path gram.

Part 1: In the second article of the series, the author designs the map of the semantic potential of the Nominal KAŊ locution and corroborates it by analyzing formal properties of this construction
The safety of vasopressor-induced hypertension in subarachnoid hemorrhage patients with coexisting unruptured, unprotected intracranial aneurysms
Authors: Reynolds Matthew R. , Buckley Robert T. , Indrakanti Santoshi S. , Turkmani Ali H. , Oh Gerald , Crobeddu Emanuela , Fargen Kyle M. , El Ahmadieh Tarek Y. , Naidech Andrew M. , Amin-Hanjani Sepideh , Lanzino Giuseppe , Hoh Brian L. , Bendok Bernard R. , Zipfel Gregory J.
Published: July 2015

OBJECT

Vasopressor-induced hypertension (VIH) is an established treatment for patients with aneurysmal subarachnoid hemorrhage (SAH) who develop vasospasm and delayed cerebral ischemia (DCI). However, the safety of VIH in patients with coincident, unruptured, unprotected intracranial aneurysms is uncertain.

METHODS

This retrospective multiinstitutional study identified 1) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who required VIH therapy (VIH group), and 2) patients with aneurysmal SAH and 1 or more unruptured, unprotected aneurysms who did not require VIH therapy (non-VIH group). All patients had previously undergone surgical or endovascular treatment for the presumed ruptured aneurysm. Comparisons between the VIH and non-VIH patients were made in terms of the patient characteristics, clinical and radiographic severity of SAH, total number of aneurysms, number of ruptured/unruptured aneurysms, aneurysm location/size, number of unruptured and unprotected aneurysms during VIH, severity of vasospasm, degree of hypervolemia, and degree and duration of VIH therapy.

RESULTS

For the VIH group (n = 176), 484 aneurysms were diagnosed, 231 aneurysms were treated, and 253 unruptured aneurysms were left unprotected during 1293 total days of VIH therapy (5.12 total years of VIH therapy for unruptured, unprotected aneurysms). For the non-VIH group (n = 73), 207 aneurysms were diagnosed, 93 aneurysms were treated, and 114 unruptured aneurysms were left unprotected. For the VIH and non-VIH groups, the mean sizes of the ruptured (7.2 ± 0.3 vs 7.8 ± 0.6 mm, respectively; p = 0.27) and unruptured (3.4 ± 0.2 vs 3.2 ± 0.2 mm, respectively; p = 0.40) aneurysms did not differ. The authors observed 1 new SAH from a previously unruptured, unprotected aneurysm in each group (1 of 176 vs 1 of 73 patients; p = 0.50). Baseline patient characteristics and comorbidities were similar between groups. While the degree of hypervolemia was similar between the VIH and non-VIH patients (fluid balance over the first 10 days of therapy: 3146.2 ± 296.4 vs 2910.5 ± 450.7 ml, respectively; p = 0.67), VIH resulted in a significant increase in mean arterial pressure (mean increase over the first 10 days of therapy relative to baseline: 125.1% ± 1.0% vs 98.2% ± 1.2%, respectively; p < 0.01) and systolic blood pressure (125.6% ± 1.1% vs. 104.1% ± 5.2%, respectively; p < 0.01).

CONCLUSIONS

For small, unruptured, unprotected intracranial aneurysms in SAH patients, the frequency of aneurysm rupture during VIH therapy is rare. The authors do not recommend withholding VIH therapy from these patients.
Restoration of ankle movements with the ActiGait implantable drop foot stimulator: a safe and reliable treatment option for permanent central leg palsy
Authors: Martin Klaus Daniel , Polanski Witold Henryk , Schulz Anne-Kathrin , Jöbges Michael , Hoff Hansjoerg , Schackert Gabriele , Pinzer Thomas , Sobottka Stephan B.
Published: July 2015

OBJECT

The ActiGait drop foot stimulator is a promising technique for restoration of lost ankle function by an implantable hybrid stimulation system. It allows ankle dorsiflexion by active peroneal nerve stimulation during the swing phase of gait. In this paper the authors report the outcome of the first prospective study on a large number of patients with stroke-related drop foot.

METHODS

Twenty-seven patients who experienced a stroke and with persisting spastic leg paresis received an implantable ActiGait drop foot stimulator for restoration of ankle movement after successful surface test stimulation. After 3 to 5 weeks, the stimulator was activated, and gait speed, gait endurance, and activation time of the system were evaluated and compared with preoperative gait tests. In addition, patient satisfaction was assessed using a questionnaire.

RESULTS

Postoperative gait speed significantly improved from 33.9 seconds per 20 meters to 17.9 seconds per 20 meters (p < 0.0001), gait endurance from 196 meters in 6 minutes to 401 meters in 6 minutes (p < 0.0001), and activation time from 20.5 seconds to 10.6 seconds on average (p < 0.0001). In 2 patients with nerve injury, surgical repositioning of the electrode cuff became necessary. One patient showed a delayed wound healing, and in another patient the system had to be removed because of a wound infection. Marked improvement in mobility, social participation, and quality of life was confirmed by 89% to 96% of patients.

CONCLUSIONS

The ActiGait implantable drop foot stimulator improves gait speed, endurance, and quality of life in patients with stroke-related drop foot. Regarding gait speed, the ActiGait system appears to be advantageous compared with foot orthosis or surface stimulation devices. Randomized trials with more patients and longer observation periods are needed to prove the long-term benefit of this device.
Magnetic resonance susceptibility weighted imaging in neurosurgery: current applications and future perspectives
Authors: Di Ieva Antonio , Lam Timothy , Alcaide-Leon Paula , Bharatha Aditya , Montanera Walter , Cusimano Michael D.
Published: July 2015

Susceptibility weighted imaging (SWI) is a relatively new imaging technique. Its high sensitivity to hemorrhagic components and ability to depict microvasculature by means of susceptibility effects within the veins allow for the accurate detection, grading, and monitoring of brain tumors. This imaging modality can also detect changes in blood flow to monitor stroke recovery and reveal specific subtypes of vascular malformations. In addition, small punctate lesions can be demonstrated with SWI, suggesting diffuse axonal injury, and the location of these lesions can help predict neurological outcome in patients. This imaging technique is also beneficial for applications in functional neurosurgery given its ability to clearly depict and differentiate deep midbrain nuclei and close submillimeter veins, both of which are necessary for presurgical planning of deep brain stimulation. By exploiting the magnetic susceptibilities of substances within the body, such as deoxyhemoglobin, calcium, and iron, SWI can clearly visualize the vasculature and hemorrhagic components even without the use of contrast agents. The high sensitivity of SWI relative to other imaging techniques in showing tumor vasculature and microhemorrhages suggests that it is an effective imaging modality that provides additional information not shown using conventional MRI. Despite SWI’s clinical advantages, its implementation in MRI protocols is still far from consistent in clinical usage. To develop a deeper appreciation for SWI, the authors here review the clinical applications in 4 major fields of neurosurgery: neurooncology, vascular neurosurgery, neurotraumatology, and functional neurosurgery. Finally, they address the limitations of and future perspectives on SWI in neurosurgery.
Robotic intercostal nerve harvest: a feasibility study in a pig model
Authors: Miyamoto Hideaki , Serradori Thomas , Mikami Yoji , Selber Jesse , Santelmo Nicola , Facca Sybille , Liverneaux Philippe
Published: July 2015

The aim of this study was to report the feasibility of robotic intercostal nerve harvest in a pig model. A surgical robot, the da Vinci Model S system, was installed after the creation of 3 ports in the pig’s left chest. The posterior edges of the fourth, fifth, and sixth intercostal nerves were isolated at the level of the anterior axillary line. The anterior edges of the nerves were transected at the rib cartilage zone. Three intercostal nerve harvesting procedures, requiring an average of 33 minutes, were successfully performed in 3 pigs without major complications.

The advantages of robotic microsurgery for intercostal nerve harvest include elimination of physiological tremor, free movement of joint-equipped robotic arms, and amplification of the surgeon’s hand motion by as much as 5 times. Robot-assisted neurolysis may be clinically useful for intercostal nerve harvest for brachial plexus reconstruction.
Management of idiopathic pediatric syringohydromyelia
Authors: Rodriguez Analiz , Kuhn Elizabeth N. , Somasundaram Aravind , Couture Daniel E.
Published: July 2015

OBJECT

Syringohydromyelia is frequently identified on spinal imaging. The literature provides little guidance to decision making regarding the need for follow-up or treatment. The purpose of this study was to review the authors' experience in managing pediatric syringohydromyelia of unknown cause.

METHODS

A single-institution retrospective review of all cases involving pediatric patients who underwent spinal MRI from 2002 to 2012 was conducted. Patients with idiopathic syringohydromyelia (IS) were identified and categorized into 2 subgroups: uncomplicated idiopathic syrinx and IS associated with scoliosis. Clinical and radiological course were analyzed.

RESULTS

Ninety-eight patients (50 female, 48 male) met the inclusion criteria. Median age at diagnosis of syrinx was 11.9 years. Median maximum syrinx size was 2 mm (range 0.5–17 mm) and spanned 5 vertebral levels (range 1–20 vertebral levels). Thirty-seven patients had scoliosis. The most common presenting complaint was back pain (26%). Clinical follow-up was available for 78 patients (80%), with a median follow-up of 20.5 months (range 1–143 months). A neurological deficit existed at presentation in 36% of the patients; this was either stable or improved at last follow-up in 64% of cases. Radiological follow-up was available for 38 patients (39%), with a median duration of 13 months (range 2–83 months). There was no change in syrinx size in 76% of patients, while 16% had a decrease and 8% had an increase in syrinx size. Thirty-six patients had both clinical and radiological follow-up. There was concordance between clinical and radiological course in 14 patients (39%), with 11 patients (31%) showing no change and 3 patients (8%) showing clinical and radiological improvement.

No patients had concurrent deterioration in clinical and radiological course. One patient with scoliosis and muscular dystrophy underwent direct surgical treatment of the syrinx and subsequently had a deteriorated clinical course and decreased syrinx size.

CONCLUSIONS

There remains a paucity of data regarding the management of pediatric IS. IS in association with scoliosis can complicate neurosurgical decision making. There was no concordance between radiological syrinx size increase and clinical deterioration in this cohort, indicating that surgical decision making should reflect clinical course as opposed to radiological course.
Assessment of Community Exposure to Ambient Respirable Crystalline Silica near Frac Sand Processing Facilities
Authors: Richards John , Brozell Todd
Published: July 2015

Due the rapid expansion of frac sand production, local residents, community leaders, and state regulatory authorities have expressed concerns regarding the lack of ambient respirable crystalline silica concentration data for areas near to these facilities. Long-term average data are needed to compare the fence line concentrations against chronic reference exposure guidelines such as the one adopted by the California Office of Environmental Health Hazard Assessment (OEHHA). This paper provides comprehensive sets of 24 h respirable crystalline silica concentration measurements compiled during multi-year sampling programs at the fence lines of four Wisconsin facilities—three frac sand mines and one frac sand processing plant. The authors adapted Environmental Protection Agency (EPA) reference method PM2.5 filter-based samplers to provide respirable (PM4) filter samples. Crystalline silica content of the PM4 particulate matter samples was measured using National Institute of Occupational Safety and Health (NIOSH) Method 7500 X-ray diffraction. The respirable crystalline silica limit of quantification was 0.31 µg/m3. The geometric mean (GM) respirable crystalline silica concentrations at the fence lines of the frac sand-producing facilities were less than 10% of the 3.0 µg/m3 California OEHHA chronic exposure level and were consistent with background concentrations throughout the upper Midwest of the U.S.
Cluster Analysis of the Wind Events and Seasonal Wind Circulation Patterns in the Mexico City Region
Authors: Carreón-Sierra Susana , Salcido Alejandro , Castro Telma , Celada-Murillo Ana-Teresa
Published: July 2015

The residents of Mexico City face serious problems of air pollution. Identifying the most representative scenarios for the transport and dispersion of air pollutants requires the knowledge of the main wind circulation patterns. In this paper, a simple method to recognize and characterize the wind circulation patterns in a given region is proposed and applied to the Mexico City winds (2001–2006). This method uses a lattice wind approach to model the local wind events at the meso-β scale, and hierarchical cluster analysis to recognize their agglomerations in their phase space. Data of the meteorological network of Mexico City was used as input for the lattice wind model. The Ward’s clustering algorithm with Euclidean distance was applied to organize the model wind events in seasonal clusters for each year of the period. Comparison of the hourly population trends of these clusters permitted the recognition and detailed description of seven circulation patterns. These patterns resemble the qualitative descriptions of the Mexico City wind circulation modes reported by other authors. Our method, however, permitted also their quantitative characterization in terms of the wind attributes of velocity, divergence and vorticity, and an estimation of their seasonal and annual occurrence probabilities, which never before were quantified.
Pro-Lie Groups: A Survey with Open Problems
Authors: Hofmann Karl , Morris Sidney
Published: July 2015

A topological group is called a pro-Lie group if it is isomorphic to a closed subgroup of a product of finite-dimensional real Lie groups. This class of groups is closed under the formation of arbitrary products and closed subgroups and forms a complete category. It includes each finite-dimensional Lie group, each locally-compact group that has a compact quotient group modulo its identity component and, thus, in particular, each compact and each connected locally-compact group; it also includes all locally-compact Abelian groups. This paper provides an overview of the structure theory and the Lie theory of pro-Lie groups, including results more recent than those in the authors’ reference book on pro-Lie groups. Significantly, it also includes a review of the recent insight that weakly-complete unital algebras provide a natural habitat for both pro-Lie algebras and pro-Lie groups, indeed for the exponential function that links the two. (A topological vector space is weakly complete if it is isomorphic to a power RX of an arbitrary set of copies of R. This class of real vector spaces is at the basis of the Lie theory of pro-Lie groups.) The article also lists 12 open questions connected to pro-Lie groups.
Vitamins and Melanoma
Authors: Russo Irene , Caroppo Francesca , Alaibac Mauro
Published: July 2015

A tremendous amount of information was published over the past decades in relation to the role of vitamins in various neoplastic diseases. In particular, several studies showed an inverse relationship between selected vitamins intake and cancer risk. In this review we will focus on the role played by vitamins in melanoma with particular regard to vitamin A, D, K, E and C. Given that vitamin supplementation is easy, convenient, and readily accepted by patients, in the future the use of vitamins in chemoprevention and therapy of melanoma could be encouraged if supported by pre-clinical and clinical evidence.
Effect of ZIF-8 Crystal Size on the O2 Electro-Reduction Performance of Pyrolyzed Fe–N–C Catalysts
Authors: Armel Vanessa , Hannauer Julien , Jaouen Frédéric
Published: July 2015

The effect of ZIF-8 crystal size on the morphology and performance of Fe–N–C catalysts synthesized via the pyrolysis of a ferrous salt, phenanthroline and the metal-organic framework ZIF-8 is investigated in detail. Various ZIF-8 samples with average crystal size ranging from 100 to 1600 nm were prepared. The process parameters allowing a templating effect after argon pyrolysis were investigated. It is shown that the milling speed, used to prepare catalyst precursors, and the heating mode, used for pyrolysis, are critical factors for templating nano-ZIFs into nano-sized Fe–N–C particles with open porosity. Templating could be achieved when combining a reduced milling speed with a ramped heating mode. For templated Fe–N–C materials, the performance and activity improved with decreased ZIF-8 crystal size. With the Fe–N–C catalyst templated from the smallest ZIF-8 crystals, the current densities in H2/O2 polymer electrolyte fuel cell at 0.5 V reached ca. 900 mA cm−2, compared to only ca. 450 mA cm−2 with our previous approach. This templating process opens the path to a morphological control of Fe–N–C catalysts derived from metal-organic frameworks which, when combined with the versatility of the coordination chemistry of such materials, offers a platform for the rational design of optimized Metal–N–C catalysts.
Iron Fischer-Tropsch Catalysts Prepared by Solvent-Deficient Precipitation (SDP): Effects of Washing, Promoter Addition Step, and Drying Temperature
Authors: Brunner Kyle , Huang Baiyu , Woodfield Brian , Hecker William
Published: July 2015

A novel, solvent-deficient precipitation (SDP) method for catalyst preparation in general and for preparation of iron FT catalysts in particular is reported. Eight catalysts using a 23 factorial design of experiments to identify the key preparation variables were prepared. The catalysts were characterized by electron microprobe, N2 adsorption, TEM, XRD, and ICP. Results show that the morphology of the catalysts, i.e., surface area, pore volume, pore size distribution, crystallite sizes, and promoter distribution are significantly influenced by (1) whether or not the precursor catalyst is washed, (2) the promoter addition step, and (3) the drying condition (temperature). Consequently, the activity, selectivity, and stability of the catalysts determined from fixed-bed testing are also affected by these three variables. Unwashed catalysts prepared by a one-step method and dried at 100 °C produced the most active catalysts for FT synthesis. The catalysts of this study prepared by SDP compared favorably in activity, productivity, and stability with Fe FT catalysts reported in the literature. It is believed that this facile SDP approach has promise for development of future FT catalysts, and also offers a potential alternate route for the preparation of other catalysts for various other applications.
Security Property Validation of the Sensor Network Encryption Protocol (SNEP)
Authors: Islam Salekul
Published: July 2015

Since wireless sensor networks (WSNs) have been designed to be deployed in an unsecured, public environment, secured communication is really vital for their wide-spread use. Among all of the communication protocols developed for WSN, the Security Protocols for Sensor Networks (SPINS) is exceptional, as it has been designed with security as a goal. SPINS is composed of two building blocks: Secure Network Encryption Protocol (SNEP) and the “micro” version of the Timed Efficient Streaming Loss-tolerant Authentication (TESLA), named μTESLA. From the inception of SPINS, a number of efforts have been made to validate its security properties. In this paper, we have validated the security properties of SNEP by using an automated security protocol validation tool, named AVISPA. Using the protocol specification language, HLPSL, we model two combined scenarios—node to node key agreement and counter exchange protocols—followed by data transmission. Next, we validate the security properties of these combined protocols, using different AVISPA back-ends. AVISPA reports the models we have developed free from attacks. However, by analyzing the key distribution sub-protocol, we find one threat of a potential DoS attack that we have demonstrated by modeling in AVISPA. Finally, we propose a modification, and AVISPA reports this modified version free from the potential DoS attack.
Non-Fourier Heat Transfer with Phonons and Electrons in a Circular Thin Layer Surrounding a Hot Nanodevice
Authors: Cimmelli Vito , Carlomagno Isabella , Sellitto Antonio
Published: July 2015

A nonlocal model for heat transfer with phonons and electrons is applied to infer the steady-state radial temperature profile in a circular layer surrounding an inner hot component. Such a profile, following by the numerical solution of the heat equation, predicts that the temperature behaves in an anomalous way, since for radial distances from the heat source smaller than the mean-free path of phonons and electrons, it increases for increasing distances. The compatibility of this temperature behavior with the second law of thermodynamics is investigated by calculating numerically the local entropy production as a function of the radial distance. It turns out that such a production is positive and strictly decreasing with the radial distance.
Flexible Electronics: Integration Processes for Organic and Inorganic Semiconductor-Based Thin-Film Transistors
Authors: Vidor Fábio , Meyers Thorsten , Hilleringmann Ulrich
Published: July 2015

Flexible and transparent electronics have been studied intensively during the last few decades. The technique establishes the possibility of fabricating innovative products, from flexible displays to radio-frequency identification tags. Typically, large-area polymeric substrates such as polypropylene (PP) or polyethylene terephthalate (PET) are used, which produces new requirements for the integration processes. A key element for flexible and transparent electronics is the thin-film transistor (TFT), as it is responsible for the driving current in memory cells, digital circuits or organic light-emitting devices (OLEDs). In this paper, we discuss some fundamental concepts of TFT technology. Additionally, we present a comparison between the use of the semiconducting organic small-molecule pentacene and inorganic nanoparticle semiconductors in order to integrate TFTs suitable for flexible electronics. Moreover, a technique for integration with a submicron resolution suitable for glass and foil substrates is presented.
An Optimal PR Control Strategy with Load Current Observer for a Three-Phase Voltage Source Inverter
Authors: Dou Xiaobo , Yang Kang , Quan Xiangjun , Hu Qinran , Wu Zaijun , Zhao Bo , Li Peng , Zhang Shizhan , Jiao Yang
Published: July 2015

Inverter voltage control is an important task in the operation of a DC/AC microgrid system. To improve the inverter voltage control dynamics, traditional approaches attempt to measure and feedforward the load current, which, however, needs remote measurement with communications in a microgrid system with distributed loads. In this paper, a load current observer (LCO) based control strategy, which does not need remote measurement, is proposed for sinusoidal signals tracking control of a three-phase inverter of the microgrid. With LCO, the load current is estimated precisely, acting as the feedforward of the dual-loop control, which can effectively enlarge the stability margin of the control system and improve the dynamic response to load disturbance. Furthermore, multiple PR regulators are applied in this strategy conducted in a stationary frame to suppress the transient fluctuations and the total harmonic distortion (THD) of the output voltage and achieve faster transient performance compared with traditional dual-loop control in a rotating dq0 frame under instantaneous change of various types of load (i.e., balanced load, unbalanced load, and nonlinear load). The parameters of multiple PR regulators are analyzed and selected through the root locus method and the stability of the whole control system is evaluated and analyzed. Finally, the validity of the proposed approach is verified through simulations and a three-phase prototype test system with a TMS320F28335 DSP.
Application of Artificial Bee Colony in Model Parameter Identification of Solar Cells
Authors: Wang Rongjie , Zhan Yiju , Zhou Haifeng
Published: July 2015

The identification of values of solar cell parameters is of great interest for evaluating solar cell performances. The algorithm of an artificial bee colony was used to extract model parameters of solar cells from current-voltage characteristics. Firstly, the best-so-for mechanism was introduced to the original artificial bee colony. Then, a method was proposed to identify parameters for a single diode model and double diode model using this improved artificial bee colony. Experimental results clearly demonstrate the effectiveness of the proposed method and its superior performance compared to other competing methods.
Inventory of Engineered Nanoparticle-Containing Consumer Products Available in the Singapore Retail Market and Likelihood of Release into the Aquatic Environment
Authors: Zhang Yuanyuan , Leu Yu-Rui , Aitken Robert , Riediker Michael
Published: July 2015

Consumer products containing engineered nanoparticles (ENP) are already entering the marketplace. This leads, inter alia, to questions about the potential for release of ENP into the environment from commercial products. We have inventoried the prevalence of ENP-containing consumer products in the Singapore market by carrying out onsite assessments of products sold in all major chains of retail and cosmetic stores. We have assessed their usage patterns and estimated release factors and emission quantities to obtain a better understanding of the quantities of ENP that are released into which compartments of the aquatic environment in Singapore. Products investigated were assessed for their likelihood to contain ENP based on the declaration of ENP by producers, feature descriptions, and the information on particle size from the literature. Among the 1,432 products investigated, 138 were “confirmed” and 293 were “likely” to contain ENP. Product categories included sunscreens, cosmetics, health and fitness, automotive, food, home and garden, clothing and footwear, and eyeglass/lens coatings. Among the 27 different types of nanomaterials identified, SiO2 was predominant, followed by TiO2 and ZnO, Carbon Black, Ag, and Au. The amounts of ENP released into the aquatic system, which was estimated on the basis of typical product use, ENP concentration in the product, daily use quantity, release factor, and market share, were in the range of several hundred tons per year. As these quantities are likely to increase, it will be important to further study the fate of ENP that reach the aquatic environment in Singapore.
Injury Risk Factors in a Small-Scale Gold Mining Community in Ghana’s Upper East Region
Authors: Long Rachel , Sun Kan , Neitzel Richard
Published: July 2015

Occupational injury is one of many health concerns related to small-scale gold mining (ASGM), but few data exist on the subject, especially in sub-Saharan Africa. In 2011 and 2013, we examined accidents, injuries, and potential risk factors in a Ghanaian ASGM community. In 2011, 173 participants were surveyed on occupational history and health, and 22 of these were surveyed again in 2013. Injury rates were estimated at 45.5 and 38.5 injuries per 100 person-years in 2011 and in 2013, respectively; these rates far surpass those of industrialized mines in the U.S. and South Africa. Demographic and job characteristics generally were not predictive of injury risk, though there was a significant positive association with injury risk for males and smokers. Legs and knees were the most common body parts injured, and falling was the most common cause of injury. The most common type of injuries were cuts or lacerations, burns and scalds, and contusions and abrasions. Only two miners had ever received any occupational safety training, and PPE use was low. Our results suggest that injuries should be a priority area for occupational health research in ASGM.
Novel Radiolytic Rotenone Derivative, Rotenoisin B with Potent Anti-Carcinogenic Activity in Hepatic Cancer Cells
Authors: Badaboina Srilatha , Bai Hyoung-Woo , Na Yun , Park Chul-Hong , Kim Tae , Lee Tae-Hoon , Chung Byung
Published: July 2015

Rotenone, isolated from roots of derris plant, has been shown to possess various biological activities, which lead to attempting to develop a potent drug against several diseases. However, recent studies have demonstrated that rotenone has the potential to induce several adverse effects such as a neurodegenerative disease. Radiolytic transformation of the rotenone with gamma-irradiation created a new product, named rotenoisin B. The present work was designed to investigate the anticancer activity of rotenoisin B with low toxicity and its molecular mechanism in hepatic cancer cells compared to a parent compound, rotenone. Our results showed rotenoisin B inhibited hepatic cancer cells’ proliferation in a dose dependent manner and increased in apoptotic cells. Interestingly, rotenoisin B showed low toxic effects on normal cells compared to rotenone. Mitochondrial transmembrane potential has been decreased, which leads to cytochrome c release. Down regulation of anti-apoptotic Bcl-2 levels as well as the up regulation of proapoptotic Bax levels were observed. The cleaved PARP (poly ADP-ribose polymerase) level increased as well. Moreover, phosphorylation of extracellular signal regulated kinase (ERK) and p38 slightly up regulated and intracellular reactive oxygen species (ROS) increased as well as cell cycle arrest predominantly at the G2/M phase observed. These results suggest that rotenoisin B might be a potent anticancer candidate similar to rotenone in hepatic cancer cells with low toxicity to normal cells even at high concentrations compared to rotenone.
Differential DNA Methylation in Relation to Age and Health Risks of Obesity
Authors: Mansego María , Milagro Fermín , Zulet María , Moreno-Aliaga María , Martínez José
Published: July 2015

The aim of this study was to evaluate whether genome-wide levels of DNA methylation are associated with age and the health risks of obesity (HRO); defined according to BMI categories as “Low HRO” (overweight and class 1 obesity) versus “High HRO” (class 2 and class 3 obesity). Anthropometric measurements were assessed in a subsample of 48 volunteers from the Metabolic Syndrome Reduction in Navarra (RESMENA) study and 24 women from another independent study, Effects of Lipoic Acid and Eicosapentaenoic Acid in Human Obesity (OBEPALIP study). In the pooled population; the methylation levels of 55 CpG sites were significantly associated with age after Benjamini-Hochberg correction. In addition, DNA methylation of three CpG sites located in ELOVL2; HOXC4 and PI4KB were further negatively associated with their mRNA levels. Although no differentially methylated CpG sites were identified in relation to HRO after multiple testing correction; several nominally significant CpG sites were identified in genes related to insulin signaling; energy and lipid metabolism. Moreover, statistically significant associations between BMI or mRNA levels and two HRO-related CpG sites located in GPR133 and ITGB5 are reported. As a conclusion, these findings from two Spanish cohorts add knowledge about the important role of DNA methylation in the age-related regulation of gene expression. In addition; a relevant influence of age on DNA methylation in white blood cells was found, as well as, on a trend level, novel associations between DNA methylation and obesity.
The miR-200 Family: Versatile Players in Epithelial Ovarian Cancer
Authors: Muralidhar Goda , Barbolina Maria
Published: July 2015

The role of microRNAs (miRNAs or miRs) in the pathology of epithelial ovarian cancer (EOC) has been extensively studied. Many miRNAs differentially expressed in EOC as compared to normal controls have been identified, prompting further inquiry into their role in the disease. miRNAs belonging to the miR-200 family have repeatedly surfaced over multiple profiling studies. In this review, we attempt to consolidate the data from different studies and highlight mechanisms by which these miRNAs influence progression of metastasis and chemo-resistance in EOC.