bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of semi-volatile organic compounds (SVOCs) in surface water, soil, and groundwater in a chemical industrial park in Eastern China
Authors: Liu Benhua , Li Yuehua , Ma Jianfeng , Huang Linxian , Chen Liang
Published: February 2016

China is suffering from serious water and soil pollution, especially in the North China Plain. This work investigated semi-volatile organic compounds (SVOCs) in surface water, groundwater and soil within a chemical industrial park in Eastern China, for which the volatile organic compound (VOC) results have been previously reported. A total of 20 samples were collected from the field, and analyzed in the laboratory. A 100% detection frequency of SVOCs in samples from this chemical industrial park was observed (same as VOCs). Moreover, the detection frequency of 113 SVOCs in each sample reached 15.93, 12.39 and 20.35% for surface water, groundwater and soil, respectively. The most detected SVOCs in the park included N-containing SVOCs, polycyclic aromatic hydrocarbons, phthalates, organic pesticides and polychlorodiphenyls. The elevated detecting frequencies and concentration levels of SVOCs identified in the groundwater were attributed to the intensive chemical production activities in the park. In addition, the agricultural activities in the area might also have contributed to the SVOCs to the groundwater. The results of VOCs and SVOCs from this and previous studies suggest that the groundwater in this industrial park has been severely contaminated, and the contamination likely spreads beyond the park. Imminent hydrogeological assessments and remedial actions are warranted to eliminate the source and mitigate the potential plume expansion beyond the park boundary.
The assessment of the coke wastewater treatment efficacy in rotating biological contractor
Authors: Cema G. , Żabczyński S. , Ziembińska-Buczyńska A.
Published: February 2016

Coke wastewater is known to be relatively difficult for biological treatment. Nonetheless, biofilm-based systems seem to be promising tool for such treatment. That is why a rotating biological contactor (RBC) system focused on the Anammox process was used in this study. The experiment was divided into two parts with synthetic and then real wastewater. It was proven that it is possible to treat coke wastewater with RBC but such a procedure requires a very long start-up period for the nitritation (190 days), as well as for the Anammox process, where stable nitrogen removal over 70% was achieved after 400 days of experiment. Interestingly, it was possible at a relatively low (20.2 ± 2.2 °C) temperature. The polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) based monitoring of the bacterial community showed that its biodiversity decreased when the real wastewater was treated and it was composed mainly of GC-rich genotypes, probably because of the modeling influence of this wastewater and the genotypes specialization.
Electrocatalytic degradation of bromocresol green wastewater on Ti/SnO2-RuO2 electrode
Authors: Bai Hongmei , He Ping , Chen Jingchao , Liu Kaili , Lei Hong , Zhang Xiaojuan , Dong Faqin , Li Hong
Published: February 2016

Thermal decomposition method was employed to prepare a Ti/SnO2-RuO2 electrode, on which electrocatalytic degradation of bromocresol green (BCG) was investigated in detail. Scanning electron microscopy, an X-ray diffraction analyzer and an X-ray fluorescence spectrometer were adopted to characterize the morphology, crystal structure and element analysis of the as-prepared Ti/SnO2-RuO2 electrode. It was indicated that the Ti/SnO2-RuO2 electrode had a ‘cracked-mud’ structure and exhibited a superior specific surface area. The removal efficiency of BCG on the Ti/SnO2-RuO2 electrode was determined in terms of chemical oxygen demand and ultraviolet-visible absorption spectrometry. The results of the batch experiment indicated that the removal efficiency of BCG was influenced by the following factors in descending order: initial pH0, reaction temperature, current density and electrolysis time. The removal efficiency of BCG reached up to 91% at the optimal experiment conditions (initial concentration of 100 mg L−1, initial pH0 7, reaction temperature of 30 °C, current density of 12 mA cm−2 and electrolysis time of 150 min). As a result, it was concluded that BCG wastewater was efficiently removed by electrochemical oxidation on the Ti/SnO2-RuO2 electrode.
Pseudomonas aeruginosa Infective Endocarditis Following Transcatheter Aortic Valve Implantation: A Note of Caution
Authors: Dapás Juan Ignacio , Rivero Cynthia , Burgos Pablo , Vila Andrea
Published: February 2016

Transcatheter aortic valve implantation (TAVI) is an alternative treatment for severe aortic valve stenosis (AS) in patients with prohibitive risk for surgical aortic valve replacement (SAVR). Prosthetic valve endocarditis (PVE) is a rare complication of this relatively novel procedure and current guidelines do not include specific recommendations for its treatment.

We report a case of PVE due to Pseudomonas aeruginosa after TAVI that required SAVR, with successful outcome.

PVE usually occurs during the first year after TAVI and entails a high mortality risk because patients eligible for this min-imally invasive procedure are fragile (i.e. advanced age and/or severe comorbidities). Additionally, clinical presentation may be atypical or subtle and transesophageal echocardiogram (TEE) may not be conclusive, which delays diagnosis and treatment worsening the prognosis. This case highlights that open SAVR might be ultimately indicated as part of treatment for TAVI-PVE despite a high-risk surgery score.
The Size of the Radial Tuberosity is Not Related to the Occurrence of Distal Biceps Tendon Ruptures: A Case-Control Study
Authors: Kodde Izaäk F. , van den Bekerom Michel P.J. , Mulder Paul G.H. , Eygendaal Denise
Published: February 2016

Introduction:

Hypertrophic changes at the radial tuberosity have traditionally been related to distal biceps tendon degeneration and rupture. From supination to pronation of the forearm, the space available for the distal biceps tendon between de lateral ulna and radial bicipital tuberosity (RBT) decreases by almost 50%. A hypertrophic change at the radial tuberosity further reduces this space with impingement of the distal biceps tendon as a result. The purpose of this study was to evaluate whether the size of the RBT plays a role in the pathophysiology of distal biceps tendon ruptures.

Materials and Methods:

Twenty-two consecutive patients with a surgically proven distal biceps tendon rupture were matched to controls, in a 1:1 ratio. The size of the RBT was expressed as a ratio of the maximum diameter of the radius at the RBT to the diameter of the diaphysis just distal to the RBT (RD ratio), measured on standard radiographs of the elbow. The RD ratio of patients and matched controls were compared.

Results:

The mean RD ratio in control group was 1.25 and not significantly different from the mean 1.30 in the group of patients with a distal biceps tendon rupture. Each 0.1 point increase in RD ratio results in an estimated 60% increase of the rupture odds, which was not significant either.

Conclusion:

Based on the RD ratio on conventional radiographs of the elbow, there was no significant difference in RBT size between patients with a distal biceps tendon rupture and matched controls without biceps tendon pathology.
Production of polygalacturonase by Aspergillus niger BC23 isolated from Irvingia gabonensis (African mango) fruit
Authors: Ogbonnaya Nwokoro , Chukwuemeka Eze
Published: February 2016

Polygalacturonase was produced from Aspergillus niger BC 23 which was
isolated from spoiled Irvingia gabonensis fruit. The influence of carbon
substrates on enzyme production showed that the medium containing sucrose
produced a maximum enzyme yield of 38.5 U/mg protein after 72 h. Enzyme
productivity in this medium was much higher than in the medium that contained
only citrus pectin as the sole carbon source. Medium containing yeast extract
as a nitrogen source caused the production of specific enzyme activity of
31.2 U/mg protein. Results on the effect of metal ions on enzyme activity
showed that Ca2+ gave a percent relative activity of 214% in comparison to
the native enzyme activity. The enzyme showed maximum activity in slight acid
and neutral pH media with optimal activity at pH 4.0. Temperature activity
profile of the enzyme showed best activity at a temperature of 35?C. Dried
fruit peels were tested for their abilities to support enzyme production in a
media devoid of citrus pectin. The best enzyme productivity of 102.3 U/mg
protein was achieved after 72 h in the medium containing orange peel and this
level was much higher than that achieved when pure carbon sources or citrus
pectin alone were used for enzyme production.
Energy and economic effects of CHP with combined technologies of corn cobs gasification and gas turbines
Authors: Gutesa Milana , Gvozdenac-Urosevic Branka , Grkovic Vojin
Published: February 2016

This paper presents the performance and economic analysis of the gas turbine
with co-firing gas from corn cob gasification and natural gas. Adiabatic and
non-adiabatic expansion in the turbine is considered. The analysis is
performed parametrically with corn cob gasification gas and natural gas
ratio. The volumetric energy content of fuels with different share of gas
from the corn cob gasification therefore, with different calorific values, is
compared by means of the Wobbe Index. In energy and economic analyses, the
following configurations are dealt with: single manifold, dual manifold and
separate gas systems.
Advanced induction motor drive control with single current sensor
Authors: Adzic Evgenije , Porobic Vlado , Adzic Milan , Ivanovic Zoran
Published: February 2016

This paper proposes induction motor drive control method which uses minimal
number of sensors, providing only DC-link current as a feedback signal.
Improved DC-link current sampling scheme and modified asymmetrical switching
pattern cancels characteristic waveform errors which exist in all three
reconstructed motor line-currents. Motor linecurrent harmonic content is
reduced to an acceptable level, eliminating torque and speed oscillations
which were inherent for conventional single sensor drives. Consequently, use
of single current sensor and line-current reconstruction technique is no
longer acceptable only for low and medium performance drives, but also for
drives where priority is obtaining a highly accurate, stable and fast
response. Proposed control algorithm is validated using induction motor drive
hardware prototype based on TMS320F2812 digital signal processor.
A comprehensive procedure for development of power electronics control systems
Authors: Grabic Stevan , Vekic Marko , Rapaic Milan
Published: February 2016

This paper analyses several tools and methods for the comprehensive and
efficient development of Power Electronics control systems. Hardware In the
Loop technology enhances a possibility for compromising two opposing demands:
the requirement for exhausting testing process and a requirement for as short
time to market as possible. The procedure was presented through development
and testing of one complex control algorithm for the connection of the
permanent magnet synchronous generator to the electrical grid. Development
steps are explained and analysed in detail. Finally, several scenarios based
on presented tools and methods are proposed.
Energy indicators for public buildings in autonomous province of Vojvodina with focus on healthcare, educational and administrative buildings
Authors: Petrovic Jovan , Medojevic Milovan , Mujan Igor
Published: February 2016

This paper aims to show the current state of energy consumption and
accompanying energy indicators in the public building sector in The
Autonomous Province of Vojvodina, Serbia. The public building energy
consumption data (healthcare, administration and schools) was collected by
surveys supported by on-site measurements, calculations and interviews with
people responsible for energy monitoring. Statistical processing of the
collected data on the real extent and manner of energy usage in public
buildings in Vojvodina was used. This paper presents energy indicators which
are on average three times higher than allowed by Serbian Ordinance and what
is currently present in neighboring European Countries. It is of the utmost
importance to use this data and its implications as a catalyst for the
implementation of energy management in the public building sector and an
increase in energy efficiency.
Development of the multi-segment lumbar spine for humanoid robots
Authors: Pencic Marko , Borovac Branislav , Kovacevic Dusan , Cavic Maja
Published: February 2016

The paper presents development of multi-segment lumbar structure based on the
human spine. The research is performed within the project based on
development of socially acceptable robot named "SARA". Two approaches for
spine realization of humanoids exist: multi-joint viscoelastic structures
(5-10 joints) that have variable flexibility and structures that consist of
one joint - torso/waist joint, which has low elasticity and high stiffness.
We propose multi-joint flexible structure with stiff, low backlash and
self-locking mechanisms that require small actuators. Based on
kinematic-dynamic requirements dynamical model of robot is formed. Dynamical
simulation is performed for several postures of the robot and driving torques
of lumbar structure are determined. During development of the lumbar
structure 16 variant solutions are considered. Developed lumbar structure
consists of three equal segments, it has 6 DOFs (2 DOFs per segment) and
allows movements of lateral flexion ?30? and torsion ?45?, as well as the
combination of these two movements. In development phase the movements of
flexion/extension are excluded, for the bending of the body forward to an
angle of 45? is achieved by rotation in the hip joints. Proposed solution of
the lumbar structure is characterized by self-locking of mechanisms (if for
any reason actuators stop working, lumbar structure retains current posture),
low backlash (high positioning accuracy and repeatability of movements),
compactness, high carrying capacity and small dimensions.
Viability analysis of heat recovery solution for industrial process of roasting coffee
Authors: Kljajic Miroslav , Andjelkovic Aleksandar , Gvozdenac Dusan
Published: February 2016

Every industrial heat recovery solution is specific engineering challenge but
not because predicted energy rationalization or achieved energy savings but
potential unavoidable technological deviations and consequences on related
processes and for sure, high investment because of delicate design and
construction. Often, the energy savings in a particular segment of the
industrial process is a main goal. However, in the food industry, especially
roasting coffee, additional criteria has to be strictly observed and
fulfilled. Such criteria may include prescribed and uniform product quality,
compliance with food safety standards, stability of the processes etc., and
all in the presence of key process parameters variability, inconsistency of
raw material composition and quality, complexity of measurement and
analytical methods etc. The paper respects all circumstances and checks
viability of proposed recovery solution. The paper analyzes the possibility
of using waste heat from the roasting process to ensure shortening of
roasting cycle, reduction of fuel consumption and increasing capacity of
roasting lines on daily basis. Analysis concludes that effects are valuable
and substantial, although the complete solution is on the threshold of
economic sustainability with numerous opportunities to improve of both
technical and economic indicators. The analysis combines measuring and
analytical methods with standard cost-benefit analysis. Conclusions are
derived from measurements and calculations of key parameters in the operating
conditions and checked by experimental methods. Test results deviate from 10
to 15%, in relation with parameters in main production line.
State Liability Regimes within the United States and Auditor Reporting
Authors: Anantharaman Divya , Pittman Jeffrey A. , Wans Nader
Published: February 2016

We examine how state liability regimes within the United States affect auditor reporting decisions. We exploit variation across state-level common law in two aspects of auditor liability: the extent to which auditors can be held liable by third parties for negligence, and rules for apportioning liability across multiple defendants. We find that auditors are more likely to issue a modified going-concern (GC) report to financially distressed clients from high-liability states than to those from low-liability states. We sharpen inferences using a natural experiment that examines the causal effects of two exogenous shocks to auditor third-party liability standards, which dramatically restricted auditors' liability in New Jersey in 1995 and in California in 1992. Results from difference-in-differences tests imply that auditors' propensity to issue a modified opinion for client firms in New Jersey and California decreases significantly after the decline in auditors' litigation exposure, relative to control firms from other jurisdictions. These findings add to our understanding of how litigation risk affects auditor behavior and highlight an important source of variation in litigation risk within the U.S. that has seldom been studied to date.
Malleable Standards of Care Required by Jurors When Assessing Auditor Negligence
Authors: Maksymov Eldar M. , Nelson Mark W.
Published: February 2016

We report the results of four experiments investigating the relationship between (1) the quality of an audit, (2) jurors' assessments of the standard of prudent care (SOC) against which audit quality is compared, and (3) jurors' negligence verdicts. Experiment 1 operationalizes audit quality by varying the sample size used in audit testing, and provides evidence that jurors anchor their assessment of SOC on audit quality, producing a “competitive mediation” in which audit quality reduces the potential for a negligence verdict directly, but increases that potential indirectly by increasing SOC. Experiment 2 generalizes this finding to a setting that operationalizes audit quality by varying the size of adjustment the auditor required. Experiments 3 and 4 extend these results to a setting in which SOC is elicited after jurors make negligence verdicts. Overall, these experiments provide insight into the role of SOC in constraining and justifying negligence verdicts.

Data Availability: Contact the authors.
Correlates of External Quality Assessment and Improvement Programs in Internal Auditing: A Study of 68 Countries
Authors: DeSimone Steven M. , Abdolmohammadi Mohammad
Published: February 2016

We use survey responses from 1,053 chief audit executives (CAEs) of public companies located in 68 countries to investigate the theoretical correlates of the use of external quality assessment and improvement programs (ExternalQAIP) for the Internal Audit Function (IAF). Our test variables are (1) internal quality assessment and improvement programs (InternalQAIP) and its related components and IAF performance measures, (2) chief audit executive competence, (3) audit committee involvement with the internal audit, (4) IAF age, (5) IAF outsourcing status (in-house or outsourced), and (6) the nature of the IAF's work (work performed by IAF). We find support for our hypothesized associations between various measures of InternalQAIP and ExternalQAIP. We also find significant and positive results for associations between audit committee involvement and IAF age and ExternalQAIP. However, we do not find significant results for in-house or outsourcing of internal audit activities, CAE competence, or control variables. Our results should be of interest to management, CAEs, corporate boards, regulators, and external auditors.

Data Availability: Please contact The Institute of Internal Auditors Research Foundation (IIARF) that owns the CBOK (2010) database used in this study.
A Review of the Uses of Nuclear Radiation in Tobacco and Smoke Research
Authors: Jenkins RW
Published: February 2016

In summary, nuclear radiation has been widely used to elucidate many aspects of the mechanisms of tobacco being converted to smoke. In addition, the mechanisms of smoke transfer, tobacco inorganic chemistry and smoke filtration have been clarified by many authors worldwide. The newer techniques now being developed, using radiation detection coupled with the enhanced use of electronic-data reduction and interpretation, promise to continue the important role these techniques have played in understanding smoke-formation mechanisms.
Effect of Exogenous Potassium on the Reduction in Tar, Nicotine and Carbon Monoxide Deliveries in the Mainstream Smoke of Cigarettes
Authors: Yamamoto T , Umemura S , Kaneko H
Published: February 2016

Deliveries of tar, nicotine and carbon monoxide in mainstream smoke decreased as the exogenous-potassium content of tobacco increased. The puff count was almost unchanged with added potassium malate, but slightly decreased with added nitrate. Potassium malate was more effective than the nitrate for the reduction of carbon monoxide, whereas the opposite was observed in the case of nicotine. Both the exogenous and the endogenous potassium contents influenced the reduction of carbon-monoxide delivery through a decrease in the peak temperature of the burning cone. The pungency and off-taste peculiar to the tobacco were eliminated to some extent by the addition of potassium malate at levels less than 2 % expressed as potassium.
Medial Longitudinal Arch Development of Children Aged 7 to 9 Years: Longitudinal Investigation
Authors: Tong Jasper W.K. , Kong Pui W.
Published: February 2016

Background

It is unclear at what age the medial longitudinal arch (MLA) of the foot becomes stable in children. The influence of footwear on MLA development also is unknown.

Objective

The purpose of this study was to examine the MLA development of children using a longitudinal approach. The relationship between wearing different types of footwear and MLA development also was explored longitudinally.

Design

This was a longitudinal cohort observational study.

Methods

The MLA of 111 healthy children (mean age=6.9 years, SD=0.3) was evaluated using 3 parameters (arch index [AI], midfoot peak pressure [PP], and maximum force [MF]) extracted from dynamic foot loading measurements at baseline (t0), 10-month follow-up (t1), and 22-month follow-up (t2). Information on footwear usage was surveyed. Linear mixed modeling was used to test for differences in MLA over time.

Results

The MLA of the children remained stable over time (AI: t0/t1/t2=0.25 [95% confidence interval (CI)=0.24, 0.26]/0.25 [95% CI=0.24, 0.26]/0.25 [95% CI=0.24, 0.26]; P=.95). When the children's sex was considered, the AI of boys decreased (higher arch) with age (0.26 [95% CI=0.24, 0.27]/0.25 [95% CI=0.24, 0.27]/0.25 [95% CI=0.23, 0.27]; P=.02). Boys also displayed a flatter MLA than girls at age 6.9 years (AI: mean difference=0.02 [95% CI=0.01, 0.04]; P=.02). At baseline, children who wore closed-toe shoes displayed the lowest MLA overall (AI: closed-toe shoes/sandals/slippers=0.26 [95% CI=0.24, 0.28]/0.24 [95% CI=0.23, 0.25]/0.25 [95% CI=0.24, 0.26]; P<.01). Children who used slippers at toddlers' age experienced a higher PP (flatter arch) in later childhood than those who wore sandals (mean difference=31.60 kPa [95% CI=1.44, 61.75]; post hoc P=.04).

Limitations

Information on the type of footwear worn was self-reported and, therefore, may be subjected to recall bias.

Conclusions

The MLA of children remained stable from 7 to 9 years of age. The child's sex and the type of footwear worn during childhood may influence MLA development.
Population Synthesis in Activity-Based Models
Authors: Choupani Abdoul-Ahad , Mamdoohi Amir Reza
Published: February 2016

Activity-based travel demand modeling requires socioeconomic micro-data of the population under study. Because the acquisition of such data for the entire population is infeasible or highly expensive, techniques such as iterative proportional fitting (IPF) have been applied extensively to estimate such data for the population, synthetically. Despite its many advantages, IPF results in noninteger values instead of integers: fractions of households or individuals are obtained for zones. Although methods have been proposed to produce integers for noninteger tables, seldom has this problem been viewed as tabular rounding. This paper proposes a binary linear programming model for tabular rounding in which the integer-converted table totals and marginal sums perfectly fit the input data obtained from the Census Bureau. Furthermore, the model minimizes distortion to the correlation structure of the household- and individual-level noninteger tables. The model does not bias the joint or marginal distributions of the socioeconomic attributes of population units or the sampling of rare demographic groups (at a significance level of a = .05). The empirical comparison of the proposed method with eight existing methods demonstrates that the proposed model outperforms the tested methods. Sensitivity analysis demonstrates that the integer conversion of small values is as significant as it is for large values. In this study, deterministic methods outperform stochastic methods in accuracy and perfect fit to census data. Finally, a scoring and ranking tool is used to reflect concisely the advantages and disadvantages of these methods.
Activity Pattern Models with Well-Being Indicators
Authors: Carrion Carlos , Enam Annesha , Pattabhiraman Varun , Abou-Zeid Maya , Ben-Akiva Moshe
Published: February 2016

Activity-based travel demand models, particularly a class widely used in practice known as the activity schedule approach, constitute the state of the art in metropolitan travel demand forecasting. In a 2012 paper, Abou-Zeid and Ben-Akiva proposed two extensions to the specification of the activity pattern model in the activity schedule approach. This paper focuses on the econometric extension, which involves adding happiness measurement equations to an activity pattern model to enhance the measurement of utility. This extension is tested with the activity schedule model system and data provided by the Denver Regional Council of Governments in Colorado. Furthermore, a comparison of two criteria—the goodness of fit and the efficiency—of activity pattern models with and without happiness measurement equations is presented. The results indicate that happiness measures enhance the efficiency of the estimates of the activity pattern model.
Modeling Transit Passenger Choices of Access Stop
Authors: Nassir Neema , Hickman Mark , Malekzadeh Ali , Irannezhad Elnaz
Published: February 2016

A logit discrete choice model is developed to investigate the choice of transit access stop (i.e., departure stop). The model incorporates different components of the transit service between given origin–destination pairs at given times. A choice set generation algorithm is developed to create the set of access stop choices and calculate the time-dependent impedances from each departure stop to the destination. The correlation between the choices is treated at two levels: ( a) the mode of travel and ( b) the route of travel. A nested logit model structure is adopted to account for the dependencies among the choices on the same mode, and a correction term is proposed that captures the correlation between the stop choices that results from the commonality of the routes that serve the destination. The data are from the household travel survey of 2009 in Southeast Queensland, Australia and include travel records on three public transit modes: bus, train, and ferry. The case study analysis of Southeast Queensland shows the effectiveness of the proposed correction by demonstrating improvements in modeling the choice of access stop. The research concludes a new finding that the choice of access stop is affected not only by the attributes of the transit path between the journey ends but also, significantly and directly, by the attributes of the departure stop itself.
Unifying Long- and Short-Distance Personal Travel in a Statewide Planning Model
Authors: Stefan Kevin J. , Brownlee Alan T. , Hunt J. D.
Published: February 2016

A disaggregate behavioral tour-based microsimulation model was developed to forecast intrastate long-distance personal travel on a typical weekday as part of an overall statewide travel model system for all residents of California. A novel approach to what is traditionally described as travel generation was developed as a series of choice models focusing on consistency and integration with other components of the model system. Key features include the explicit integration of this long-distance personal travel model with the complementary short-distance personal travel model, the specification of a travel party size model for long-distance travel based on household size, and the development of models to represent characteristics of the long-distance travel tour, including duration of tour (number of nights), travel day status for a typical weekday, and time of travel within the weekday. The explicit trade-off between long- and short-distance travel produces appropriate sensitivities and reproduces the real-world phenomenon of rural travelers producing more long-distance travel. Subsequent models not described in detail in this paper take advantage of this information; in particular, party size has a significant effect on mode choice. The model system is operational and has been calibrated and validated.
Interpretation of the causes of instability of flash visual evoked potentials in intraoperative monitoring and proposal of a recording method for reliable functional monitoring of visual evoked potentials using a light-emitting device
Authors: Sato Atsushi
Published: February 2016

OBJECTIVE

Effective monitoring and application of visual evoked potentials (VEPs) during neurosurgery is a major challenge. While many monitoring methods have been effectively used, the use of VEPs as an objective determination method has not been established. The purpose of this report was to present a method for overcoming this limitation according to the use of a specific stimulus.

METHODS

Data analysis was performed in 26 cases of brain surgery. Observation was carried out for 2 groups of responses: the response derived from the start of light emission, described as the on response, and the response derived from the end of light emission, described as the off response. These reactions were separated by extending the light emission time. The waves from the visual cortex were selected from each reaction following the start and the end of light emission with consideration for the characteristics of the potential distribution. The waves were observed to characterize changes resulting from variations in duration and quantity of light emission. The results of the analysis were used to determine the optimal emission time and amount of light for effective use of wave components during VEP monitoring.

RESULTS

Stable and recordable waves were observed by monitoring the off response, consisting of the P1-N1-P2 component, with a wave latency of approximately 100 msec. Since the off response was correlated with the input, the stable wave derived from the off response could be adjusted by changing the light emission time and intensity. Individual differences in the latency of the off response were decreased by extending the light emission time and reducing the quantity of light. However, it was difficult to achieve stability by adjusting the light intensity and emission time using the on response. The off response was confirmed to be sufficiently stable for intraoperative monitoring. Moreover, during 1 case in which manipulation of the optic nerve was necessary, reduction in the off response was found to occur when the nerve was manipulated and to reverse when the manipulation stopped.

CONCLUSIONS

The off response was shown to have the capacity to function as a monitoring tool, providing more stable wave forms than the on response. Recording conditions could be adjusted to achieve a light-emitting time of 500 msec and a light quantity of 8000 Lx. Stable monitoring of VEPs using light-emitting stimuli can contribute toward improving surgical outcomes.
Clipping of previously coiled cerebral aneurysms: efficacy, safety, and predictors in a cohort of 111 patients
Authors: Daou Badih , Chalouhi Nohra , Starke Robert M. , Barros Guilherme , Ya'qoub Lina , Do John , Tjoumakaris Stavropoula , Rosenwasser Robert H. , Jabbour Pascal
Published: February 2016

OBJECTIVE

With the increasing number of aneurysms treated with endovascular coiling, more recurrences are being encountered. The aim of this study was to evaluate the efficacy and safety of microsurgical clipping in the treatment of recurrent, previously coiled cerebral aneurysms and to identify risk factors that can affect the outcomes of this procedure.

METHODS

One hundred eleven patients with recurrent aneurysms whose lesions were managed by surgical clipping between January 2002 and October 2014 were identified. The rates of aneurysm occlusion, retreatment, complications, and good clinical outcome were retrospectively determined. Univariate and multivariate logistic regressions were performed to identify factors associated with these outcomes.

RESULTS

The mean patient age was 50.5 years, the mean aneurysm size was 7 mm, and 97.3% of aneurysms were located in the anterior circulation. The mean follow-up was 22 months. Complete aneurysm occlusion, as assessed by intraoperative angiography, was achieved in 97.3% of aneurysms (108 of 111 patients). Among patients, 1.8% (2 of 111 patients) had a recurrence after clipping. Retreatment was required in 4.5% of patients (5 of 111) after clipping. Major complications were observed in 8% of patients and mortality in 2.7%. Ninety percent of patients had a good clinical outcome. Aneurysm size (OR 1.4, 95% CI 1.08–1.7; p = 0.009) and location in the posterior circulation were significantly associated with higher complications. All 3 patients who had coil extraction experienced a postoperative stroke. Aneurysm size (OR 1.2, 95% CI 1.02–1.45; p = 0.025) and higher number of interventions prior to clipping (OR 5.3, 95% CI 1.3–21.4; p = 0.019) were significant predictors of poor outcome. An aneurysm size > 7 mm was a significant predictor of incomplete obliteration and retreatment (p = 0.018).

CONCLUSIONS

Surgical clipping is safe and effective in treating recurrent, previously coiled cerebral aneurysms. Aneurysm size, location, and number of previous coiling procedures are important factors to consider in the management of these aneurysms.
Pediatric isolated thoracic and/or lumbar transverse and spinous process fractures
Authors: Akinpelu Babatunde J. , Zuckerman Scott L. , Gannon Stephen R. , Westrick Ashly , Shannon Chevis , Naftel Robert P.
Published: February 2016

OBJECTIVE

Isolated transverse and spinous process fractures (TPFx and SPFx) in the thoracic and/or lumbar region have been deemed clinically insignificant in the adult population. This same rule is often applied to the pediatric population; however, little evidence exists in this younger group. The goal of this study was to describe the clinical, radiographic, and long-term data on isolated TPFx and SPFx in an exclusively pediatric population.

METHODS

A retrospective chart review at Monroe Carell Jr. Children's Hospital at Vanderbilt University identified 82 pediatric patients with isolated TPFx and/or SPFx following a traumatic event between January 2000 and December 2013. Patient demographic information, presenting symptoms, radiographic characteristics, and follow-up data were collected. Follow-up was used to determine the outcome (presence of neurological deficits) of such injuries via complete physical examination and, when available, radiographic evidence.

RESULTS

In the 82 identified patients, the mean age was 15.5 ± 3.1 years (mean is expressed ± SD throughout), with 72 injuries (87.8%) resulting from a motor vehicle, motorcycle, or all-terrain vehicle accident. There was a mean of 1.7 ± 1.0 fractured vertebral levels involved and a mean of 1.8 ± 1.1 fractures was identified per patient. Seventy-one patients (86.6%) needed bedside pain control, 7 (8.5%) were prescribed a brace, and 4 patients (4.9%) received a collar. Physical therapy was recommended for 12 patients (14.6%). A total of 84.1% had follow-up, and the mean length of follow-up was 19 ± 37 months. No patients had true neurological deficits at presentation or follow-up as a result of their isolated fractures, whereas 95.1% had other associated system injuries.

CONCLUSIONS

These data shows that there is no appreciable long-term complication associated with isolated thoracic and/or lumbar TPFx and/or SPFx in an exclusively pediatric population. Because these fractures are, however, associated with high-energy blunt trauma, they often result in associated soft-tissue or other skeletal injury. All pediatric patients in the cohort benefited from conservative management and aggressive treatment of their comorbidities.
Vertebral compression fractures after stereotactic body radiation therapy: a large, multi-institutional, multinational evaluation
Authors: Jawad Maha Saada , Fahim Daniel K. , Gerszten Peter C. , Flickinger John C. , Sahgal Arjun , Grills Inga S. , Sheehan Jason , Kersh Ronald , Shin John , Oh Kevin , Mantel Frederick , Guckenberger Matthias
Published: February 2016

OBJECTIVE

The purpose of this study was to identify factors contributing to an increased risk for vertebral compression fracture (VCF) following stereotactic body radiation therapy (SBRT) for spinal tumors.

METHODS

A total of 594 tumors were treated with spinal SBRT as primary treatment or re-irradiation at 8 different institutions as part of a multi-institutional research consortium. Patients underwent LINAC-based, image-guided SBRT to a median dose of 20 Gy (range 8–40 Gy) in a median of 1 fraction (range 1–5 fractions). Median patient age was 62 years. Seventy-one percent of tumors were osteolytic, and a preexisting vertebral compression fracture (VCF) was present in 24% of cases. Toxicity was assessed following treatment. Univariate and multivariate analyses were performed using a logistic regression method to determine parameters predictive for post-SBRT VCF.

RESULTS

At a median follow-up of 10.1 months (range 0.03–57 months), 80% of patients had local tumor control. At the time of last imaging follow-up, at a median of 8.8 months after SBRT, 3% had a new VCF, and 2.7% had a progressive VCF. For development of any (new or progressive) VCF following SBRT, the following factors were predictive for VCF on univariate analysis: short interval from primary diagnosis to SBRT (less than 36.8 days), solitary metastasis, no additional bone metastases, no prior chemotherapy, preexisting VCF, no MRI used for target delineation, tumor volume of 37.3 cm3 or larger, equivalent 2-Gy-dose (EQD2) tumor of 41.8 Gy or more, and EQD2 spinal cord Dmax of 46.1 Gy or more. Preexisting VCF, solitary metastasis, and prescription dose of 38.4 Gy or more were predictive on multivariate analysis. The following factors were predictive of a new VCF on univariate analysis: solitary metastasis, no additional bone metastases, and no MRI used for target delineation. Presence of a solitary metastasis and lack of MRI for target delineation remained significant on multivariate analysis.

CONCLUSIONS

A VCF following SBRT is more likely to occur following treatment for a solitary spinal metastasis, reflecting a more aggressive treatment approach in patients with adequately controlled systemic disease. Higher prescription dose and a preexisting VCF also put patients at increased risk for post-SBRT VCF. In these patients, pre-SBRT cement augmentation could be considered to decrease the risk of subsequent VCF.
Transsacral transdiscal L5–S1 screws for the management of high-grade spondylolisthesis in an adolescent
Authors: Palejwala Ali , Fridley Jared , Jea Andrew
Published: February 2016

The surgical management of high-grade spondylolisthesis in adolescents remains a controversial issue. Because the basic procedure, posterolateral fusion, is associated with a significant rate of pseudarthrosis and listhesis progression, there is a pressing need for alternative surgical techniques. In the present report, the authors describe the case of an adolescent patient with significant low-back pain who was found to have Grade IV spondylolisthesis at L5–S1 that was treated with transsacral transdiscal screw fixation. Bilateral pedicle screws were placed starting from the top of the S-1 pedicle, across the L5–S1 intervertebral disc space, and into the L-5 body. At 14 months after surgery, the patient had considerable improvement in his pain and radiographic fusion across L5–S1. The authors conclude that transsacral transdiscal pedicle screws may serve as an efficacious and safe option for the correction of high-grade spondylolisthesis in adolescent patients.
Symbiotic Efficiency of Native and Exotic Rhizobium Strains Nodulating Lentil (Lens culinaris Medik.) in Soils of Southern Ethiopia
Authors: Tena Wondwosen , Wolde-Meskel Endalkachew , Walley Fran
Published: February 2016

Lentil plays a major role in the food and nutritional security of low income Ethiopian families because of the high protein content of their seed; however, their productivity typically is low largely due to soil fertility limitations. Field and pot experiments were conducted during the 2011 cropping season to determine the effectiveness of Rhizobium strains on two cultivars of lentil in Southern Ethiopia. Six rhizobial inoculant treatments (four indigenous and two commercial inoculants), a nitrogen (N) fertilizer treatment (50 kg·urea·ha−1) and an absolute control (non-inoculated non-fertilized) were used. Inoculated plants produced significantly higher nodule number, nodule dry weight, grain yield and yield components than non-inoculated non-fertilized plants. Inoculation of field grown lentil with rhizobia strain Lt29 and Lt5 enhanced seed yield by 59% and 44%, respectively. Whereas urea fertilization enhanced yields by 40%. Similarly, grain yields were increased during the pot experiment by 92% and 67% over the control treatments by inoculation with Lt29 and Lt5, respectively. The highest levels of N fixation were achieved in plants inoculated with Lt29 (65.7% Ndfa). Both field and pot investigations indicate that inoculation of lentil with native rhizobial strains replace the need for inorganic N fertilization to optimize lentil yields.
Stability of the Inherent Target Metallome in Seed Crops and a Mushroom Grown on Soils of Extreme Mineral Spans
Authors: Gramss Gerhard , Voigt Klaus-Dieter
Published: February 2016

Extremes in soil mineral supply alter the metallome of seeds much less than that of their herbage. The underlying mechanisms of mineral homeostasis and the “puzzle of seed filling” are not yet understood. Field crops of wheat, rye, pea, and the mushroom Kuehneromyces mutabilis were established on a set of metalliferous uranium mine soils and alluvial sands. Mineral concentrations in mature plants were determined from roots to seeds (and to fungal basidiospores) by ICP-MS following microwave digestion. The results referred to the concentrations of soil minerals to illustrate regulatory breaks in their flow across the plant sections. Root mineral concentrations fell to a mean of 7.8% in the lower stem of wheat in proportions deviating from those in seeds. Following down- and up-regulations in the flow, the rachis/seed interface configured with cuts in the range of 1.6%–12% (AsPbUZn) and up-regulations in the range of 106%–728% (CuMgMnP) the final grain metallome. Those of pea seeds and basidiospores were controlled accordingly. Soil concentration spans of 9–109× in CuFeMnNiZn shrank thereby to 1.3–2× in seeds to reveal the plateau of the cultivar’s desired target metallome. This was brought about by adaptations of the seed:soil transfer factors which increased proportionally in lower-concentrated soils. The plants thereby distinguished chemically similar elements (As/P; Cd/Zn) and incorporated even non-essential ones actively. It is presumed that high- and low-concentrated soils may impair the mineral concentrations of phloems as the donors of seed minerals. In an analytical and strategic top performance, essential and non-essential phloem constituents are identified and individually transferred to the propagules in precisely delimited quantities.
Factors Influencing the Safety Behavior of German Equestrians: Attitudes towards Protective Equipment and Peer Behaviors
Authors: Ikinger Christina-Maria , Baldamus Jana , Spiller Achim
Published: February 2016

Human interactions with horses entail certain risks. Although the acceptance and use of protective gear is increasing, a high number of incidents and very low or inconsistent voluntary use of safety equipment are reported. While past studies have examined factors influencing the use of safety gear, they have explored neither their influence on the overall safety behavior, nor their relative influence in relation to each other. The aim of the present study is to fill this gap. We conducted an online survey with 2572 participants. By means of a subsequent multiple regression analysis, we explored 23 different variables in view of their influence on the protective behavior of equestrians. In total, we found 17 variables that exerted a significant influence. The results show that both having positive or negative attitudes towards safety products as well as the protective behavior of other horse owners or riding pupils from the stable have the strongest influence on the safety behavior of German equestrians. We consider such knowledge to be important for both scientists and practitioners, such as producers of protective gear or horse sport associations who might alter safety behavior in such a way that the number of horse-related injuries decreases in the long term.
Two Photon Processes in an Atom Confined in Gaussian Potential
Authors: Lumb Sonia , Lumb Shalini , Prasad Vinod
Published: February 2016

Transitions of an atom under the effect of a Gaussian potential and loose spherical confinement are studied. An accurate Bernstein-polynomial (B-polynomial) method has been applied for the calculation of the energy levels and radial matrix elements. The transition probability amplitudes, transparency frequencies, and resonance enhancement frequencies for transitions to various excited states have been evaluated. The effect of the shape of confining potential on these spectral properties is studied.
The Role of HPV in Head and Neck Cancer Stem Cell Formation and Tumorigenesis
Authors: Swanson Mark , Kokot Niels , Sinha Uttam
Published: February 2016

The cancer stem cell (CSC) theory proposes that a minority of tumor cells are capable of self-replication and tumorigenesis. It is these minority of cells that are responsible for cancer metastasis and recurrence in head and neck squamous cell cancers (HNSCC). Human papilloma virus (HPV)-related cancer of the oropharynx is becoming more prevalent, which makes understanding of the relationship between HPV and CSCs more important than ever. This relationship is critical because CSC behavior can be predicted based on cell surface markers, which makes them a suitable candidate for targeted therapy. New therapies are an exciting opportunity to advance past the stalled outcomes in HNSCC that have plagued patients and clinicians for several decades.