bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychophysiological methods and criteria for the selection of individual metered loads in athletes of taekwondo section
Authors: Ohromiy G. V. , Makarova N.U. , Kasyuha A.M.
Published: November 2014

Purpose: scientific rationale approaches Express-diagnostics for athletes of taekwondo section by psychophysiological parameters. Material: Total surveyed 84 people, including 68 boys and 16 girls. Were defined backup capabilities, exercise tolerance and selection of adequate individual dose of loads in preparation for the international competition, participants - taekwondo athletes. Was attended by representatives of Ukraine, Russia and Lithuania. Age groups of participants: 6 - 16 years. Athletes have different levels and different schools of training. Results: evaluation of exercise tolerance and definition of an adequate level of motor mode in taekwondo athletes in terms of the difference of lability (DL) before and after training, revealed: high and very high nervous system (NS) lability. These figures correspond to high and very high tolerance to physical loads. The respondents who had difference of liability (DL) <0, were well-trained athletes and their high points of strength of nervous system testified about good backup capabilities (withstand great and continuous loads). In 78 % of the tested load was chosen adequately. Less than 20% of the respondents noted the average backup capabilities. They need individual correction dose loads to increase adaptive capacity. Insignificant 10%, the share of respondents had low exercise tolerance at the average values NS strength, which indicates a good backup capabilities. The direct dependence: respondents with high levels on state of health, activity and mood - low levels of anxiety, frustration, aggression and rigidity. Conclusions The proposed optimized approach Express-diagnostics according to psychophysiological parameters allow you to determine the level of physical endurance, speed adaptation athletes in the sections taekwondo and adequate response to the loads.
The problem of search safe and effective method in reducing injuries in bodybuilding stage of specialized basic training
Authors: Slavityak O.S.
Published: November 2014

Purpose: To identify the most frequently used coaches and athletes in bodybuilding principles that can help to reduce the injuries of athletes while maintaining the progressivity results. Material : a survey participated 86 coaches and 120 athletes, bodybuilders from 5 to 8 years. Results : It was found that most of the coaches used in the course of employment principles generally accepted system of training. In such circumstances, the risk of injury to athletes is large enough. When using pre-exhaustion principle to increase the intensity of the training process increases the risk of overloading the body athletes. Conclusions : Athletes with a longer training experience (about 8 years), more likely to use the principle of prior exhaustion. In this case athletes try using this principle to reduce the operating parameters of volume load. This helps to reduce the level of injury and maintain positive dynamics performance.
The system of world golf ranking among amateur players - WAGR
Authors: Tereshchuk M.V.
Published: November 2014

Purpose: justify the particular rating-WAGR and determine its value. Material: More than 40 references, including analysis of 8 protocols of Ukraine competition in golf. Results: The features and significance of the world rankings in golf among amateur players. Displaying ranking tournaments in accordance with the system of WAGR and justified the use of the conversion of the results to determine the specific places the player in the rankings. In Ukraine, held six WAGR-Tournament, the first tournament was held in 2011. Today in the world ranking of amateur players is one player from the Ukraine. Conclusions: It was found that the top-WAGR determines the level of development of the national golf federations and influence in the international arena. For the selection of athletes for the summer Youth Olympic Games is used world-rated golf amateur players (WAGR) among boys and girls.
Sensitive Organophosphorus and Carbamate Pesticides Biosensor Based on Acetylcholinesterase and CdZnSe/ZnS Ternary Alloy Quantum Dots
Authors: Hai Nguyen Ngoc , Yen Nguyen Hai , Giang Duong Thi , Nhat Nguyen Duc , Nga Pham Thu , Cao Dao Tran
Published: November 2014

This report presents the results of ternary alloy quantum dots (TQDs) manufacturing and its superior optical properties to fabricate the biosensor for pesticide detection. The explanation for the changes in PL intensity based on the change of electronic charges that alters the pH value of the surrounding environment, and the types of interaction on the surface of CdZnSe/ZnS TQDs were discussed. We show the decomposition process of the indicator (ATCh) with the catalysis from acetylcholinesterase enzyme (AChE) that inhibited by organophosphorus and carbamate pesticides including Trichlorfon (TF), Cypermethrin (CH), Abamectin (AT), and Carbosulfan (CS) with concentrations from 0.05 ppm to 10 ppm.
EIT enhanced self-Kerr nonlinearity in the three-level lambda system under Doppler broadening
Authors: Khoa Dinh Xuan , Doai Le Van , Trong Pham Van , Cuong Tran Manh , Sau Vu Ngoc , Bang Nguyen Huy , Anh Le Nguyen Mai
Published: November 2014

Using density-matrix theory, an analytical expression of the self-Kerr nonlinear coefficient of a three-level lambda EIT medium for a weak probe light is derived. Influences of the coupling light and Doppler broadening on the self-Kerr coefficient are investigated and compared to experimental observation with a good agreement. The self-Kerr nonlinearity is basically modified and greatly enhanced in the spectral region corresponding to EIT transparent window. Furthermore, sign, slope, and magnitude of the self-Kerr coefficient can be controlled with frequency and intensity of the coupling light and temperature. Such controllable Kerr nonlinearity can find interesting applications in optoelectronic devices working with low-light intensity.
Size dependent melting of Silicon nanoparticles
Authors: Hang Nguyen Thi Thuy
Published: November 2014

Melting of crystalline silicon nanoparticles is studied by molecular dynamics (MD) simulations using Stillinger-Weber potential. Models are heated up from a crystalline to a normal liquid state. Temperature dependence of total energy and the Lindemann ratio exhibit a first-order-like behavior of the transition at the melting point. Heat capacity of the system presents a single peak at around the melting point. The size dependent melting is presented. As the size of the nanoparticles increases, the variation of the melting point becomes more monotonic and the temperature range of bistability shifts to higher temperatures. In large nanoparticles, the proportion of interior atoms increases and the average potential energy per atom converges to the bulk or thin films.
Fabrication and Characterization of Single-segmented CoNiP and Multi-segment CoNiP/Au Nanowires
Authors: Tu Le Tuan , Thiem Luu Van
Published: November 2014

This paper represents the fabrication of CoNiP single segment and CoNiP/Au multisegment nanowires. We have fabricated these nanowires by electrodeposition method into polycarbonate templates with a nominal pore diameter about 100 nm. The hystersis loops were measured with the applied magnetic field parallel and perpendicular to the wire axis using a vibrating sample magnetometry (VSM). The structure morphology was observed by Scanning Electron Miroscopy (SEM) and the element composition of CoNiP/Au multisegment nanowires were analyzed by EDS. The results show that these nanowires are very uniform with the diameter of 100 nm. The observed coercivity (HC) and squareness (Mr/Ms) of CoNiP single nanowires are larger than the CoNiP/Au multisegment nanowires.
Abnormal Photoluminescence of TiO\(_{2}\) nanocrystals (nanoparticles and nanotube arrays)
Authors: Tai Ly Ngoc , Hoa Dao Thi , Hong Le Van
Published: November 2014

In this paper we report new abnormal photoluminescence results of TiO\(_{2}\) nanocrystal particles and nanotube arrays. Photoluminescence spectra were recorded for TiO\(_{2}\) nanocrystal particles and nanotube arrays that were synthesized by a wet chemical route and the electrochemical anodization, respectively. It was found that the TiO\(_{2}\) nanocrystal with small size of 5-8 nm no emitted when excited by a laser beam of 325 nm, in contrary it emitted when excited by laser beam of 442 nm. The TiO\(_{2}\) nanotube arrays exhibit a similar emission behavior. The nanotube arrays weakly emitted when excited by a laser beam of 325 nm and more strongly emitted when excited by a laser beam of 442 nm. The obtained results have been explained by a two-step exciting model and supposed to be related with the size effect of nanocrystal and it is an experimental evidence to believe that the TiO\(_{2}\) nanoparticles and nanotube arrays are applicable for photo-catalysis under sun light.
Effect of polycarboxylate superplasticiser on properties of calcium aluminate cement mortar
Authors: Ukrainczyk Neven
Published: November 2014

The effect of polycarboxylate ether (PCE)-based superplasticiser on the fresh and hardened properties of calcium aluminate cement (CAC)-based materials was investigated. Cohesion of the fresh mortar was improved by addition of methyl cellulose, thus avoiding segregation induced by the superplasticiser action. As PCE significantly retarded the setting time, lithium carbonate (Li2CO3) was investigated as an accelerator by calorimetric measurements. Compressive and flexural strengths, porosity and dynamic modulus were tested after 1 d and 9 d cured at 23°C and after transformation of metastable hydration products to stable ones at 60°C. The combined usage of PCE with methyl cellulose and lithium carbonate showed promising superplasticising properties for CAC that improved properties of the material.
Demographic Correlates of Anxiety and Depression Symptoms in Chronic Sinonasal Diseases
Authors: Katotomichelakis Michael , Simopoulos Efthimios , Tzikos Anthimos , Balatsouras Dimitrios , Tripsianis Gregory , Danielides Gerasimos , Xenitidis Kiriakos , Livaditis Miltos , Danielides Vassilios
Published: November 2014

Objectives:

To explore mental health of patients with olfactory loss due to chronic sinonasal diseases and investigate the effects of age-, gender-, and socio-economic variables on anxiety and depression symptoms.

Methodology:

One hundred and eight patients (62 males; mean age: 39.78 ± 16.11 years), suffering from olfactory impairment due to chronic rhinosinusitis and allergic rhinitis and 30 healthy subjects (16 males; mean age, 37.03 ± 13.09 years) were studied. Olfactory function was evaluated using “Sniffin‘ Sticks” test. All patients completed four validated questionnaires specific for assessing anxiety and depression (Zung Anxiety Scale, State-Trait Anxiety Inventory-STAI, Zung Depression Scale, and Beck Depression Inventory-BDI).

Results:

We found significantly more severe anxiety and depression symptoms in anosmic (all p < 0.001) and hyposmic patients compared to healthy controls. No significant differences were observed between normosmic patients and controls. Scores in all psychological measures were significantly higher in elderly and female patients as well as in low, compared to high, socio-economic status patients. No significant differences were found between low and medium socio-economic level.

Conclusions:

Olfactory loss in chronic sinonasal diseases was found to be associated with anxiety and depression symptoms. Moreover, anxiety was correlated with depression. With regard to patients' demographics, female gender and low socioeconomic status proved to be independently correlated with anxiety and depression levels.
Severe Anorexia Nervosa in a 20-Year-Old Male with Pericardial Effusion and Cortical Atrophy
Authors: Shapiro Michael , Davis Amelia A. , Nguyen Mathew L.
Published: November 2014

This case report describes a 20-year-old man with a severe presentation of anorexia nervosa. His case is unique in that he presented at 49% of his ideal body weight and had a body mass index (BMI) of 11.59. In addition, he had cognitive slowing on exam and had cortical atrophy on a head CT. Other medical complications included pericardial tamponade that was treated with an open window pericardiocentesis, hepatitis, and anemia. He was treated nutritionally, first with a Dobb-Hoff tube and then with oral feedings, as well as had group, individual, and family therapies. He responded well to treatment, his labs normalized and he was discharged at 75% of his ideal body weight after a weight increase of 40 pounds and after 106 days of hospitalization at our facility. In addition, a head CT was repeated and the cortical atrophy had resolved.
Some notes on matrix mappings and their Hausdorff measure of noncompactness
Authors: Malkowsky E. , Özger F. , Alotaibi A.
Published: November 2014

We consider the sequence spaces s0?(?B), s(c)? (?B) and s?(?B) with their
topological properties, and give the characterizations of the classes of
matrix transformations from them into any of the spaces ?1, ?1, c0 and c. We
also establish some estimates for the norms of bounded linear operators
defined by those matrix transformations. Moreover, the Hausdorff measure of
noncompactness is applied to give necessary and sufficient conditions for a
linear operator on the sets s0?(?B), s(c)?(?B) and s?(?B) to be compact.
We also close a gap in the proof of the characterizations by various authors
of matrix transformations on matrix domains.
Normal extensions of a first order differential operator
Authors: Ismailov Z.I. , Sertbaş M. , Güler B.Ö.
Published: November 2014

In the paper of W.N. Everitt and A. Zettl [26] in scalar case, all
selfadjoint extensions of the minimal operator generated by
Lagrange-symmetric any order quasi-differential expression with equal
deficiency indexes in terms of boundary conditions are described by
Glazman-Krein-Naimark method for regular and singular cases in the direct
sum of corresponding Hilbert spaces of functions. In this work, by using the
method of Calkin-Gorbachuk theory all normal extensions of the minimal
operator generated by fixed order linear singular multipoint differential
expression l = (l-, l1,... ln, l+), l-+ = d/dt + A-+, lk = d/dt + Ak
where the coefficients A-+, Ak are selfadjoint operator in separable Hilbert
spaces H-+, Hk, k= 1,..., n, n ? N respectively, are researched in the
direct sum of Hilbert spaces of vector-functions L2(H_, (-? a))? L2(H1,
(a1, b1)) ?...? L2(Hn, (an, bn)) ? L2(H+, (b,+?)) -? < a < a1 < b1 < .
.. < an < bn < b < +?. Moreover, the structure of the spectrum of normal
extensions is investigated. Note that in the works of A. Ashyralyev and O.
Gercek [2, 3] the mixed order multipoint nonlocal boundary value problem for
parabolic-elliptic equation is studied in weighed H?lder space in regular
case.
High order approximation of the inverse elliptic problem with Dirichlet-Neumann conditions
Authors: Ashyralyyev Charyyar
Published: November 2014

Inverse problem for the multidimensional elliptic equation with
Dirichlet-Neumann conditions is considered. High order of accuracy difference
schemes for the solution of inverse problem are presented. Stability, almost
coercive stability and coercive stability estimates of the third and fourth
orders of accuracy difference schemes for this problem are obtained.
Numerical results in a two dimensional case are given.
In Vivo Pancreatic β-Cell–Specific Expression of Antiaging Gene Klotho: A Novel Approach for Preserving β-Cells in Type 2 Diabetes
Authors: Lin Yi , Sun Zhongjie
Published: November 2014

Protein expression of an antiaging gene, Klotho, was depleted in pancreatic islets in patients with type 2 diabetes mellitus (T2DM) and in db/db mice, an animal model of T2DM. The objective of this study was to investigate whether in vivo expression of Klotho would preserve pancreatic β-cell function in db/db mice. We report for the first time that β-cell–specific expression of Klotho attenuated the development of diabetes in db/db mice. β-Cell–specific expression of Klotho decreased hyperglycemia and enhanced glucose tolerance. The beneficial effects of Klotho were associated with significant improvements in T2DM-induced decreases in number of β-cells, insulin storage levels in pancreatic islets, and glucose-stimulated insulin secretion from pancreatic islets, which led to increased blood insulin levels in diabetic mice. In addition, β-cell–specific expression of Klotho decreased intracellular superoxide levels, oxidative damage, apoptosis, and DNAJC3 (a marker for endoplasmic reticulum stress) in pancreatic islets. Furthermore, β-cell–specific expression of Klotho increased expression levels of Pdx-1 (insulin transcription factor), PCNA (a marker of cell proliferation), and LC3 (a marker of autophagy) in pancreatic islets in db/db mice. These results reveal that β-cell–specific expression of Klotho improves β-cell function and attenuates the development of T2DM. Therefore, in vivo expression of Klotho may offer a novel strategy for protecting β-cells in T2DM.
TLR2- and Dectin 1–Associated Innate Immune Response Modulates T-Cell Response to Pancreatic β-Cell Antigen and Prevents Type 1 Diabetes
Authors: Karumuthil-Melethil Subha , Sofi M. Hanief , Gudi Radhika , Johnson Benjamin M. , Perez Nicolas , Vasu Chenthamarakshan
Published: November 2014

The progression of autoimmune diseases is dictated by deviations in the fine balance between proinflammatory versus regulatory responses, and pathogen recognition receptors (PRRs) play a key role in maintaining this balance. Previously, we have reported that ligation of Toll-like receptor 2 (TLR2) and Dectin 1 on antigen-presenting cells by zymosan results in a regulatory immune response that prevents type 1 diabetes (T1D). Here, we show that TLR2 and Dectin 1 engagement by zymosan promotes regulatory T-cell (Treg) responses against the pancreatic β-cell–specific antigen (Ag). Unlike the TLR4 ligand, bacterial lipopolysaccharide, which induced proinflammatory cytokines and pathogenic T cells, zymosan induced a mixture of pro- and anti-inflammatory factors and Tregs, both in vitro and in vivo. Ag-specific T cells that are activated using zymosan-exposed dendritic cells (DCs) expressed Foxp3 and produced large amounts of IL-10, TGF-β1, and IL-17. NOD mice that received β-cell-Ag–loaded, zymosan-exposed DCs showed delayed hyperglycemia. Injection of NOD mice at the prediabetic age and early hyperglycemic stage with β-cell-Ag, along with zymosan, results in a superior protection of the NOD mice from diabetes as compared with mice that received zymosan alone. This therapeutic effect was associated with increased frequencies of IL-10–, IL-17–, IL-4–, and Foxp3-positive T cells, especially in the pancreatic lymph nodes. These results show that zymosan can be used as an immune regulatory adjuvant for modulating the T-cell response to pancreatic β-cell-Ag and reversing early-stage hyperglycemia in T1D.
Iterative learning control with sampled-data feedback for robot manipulators
Authors: Delchev Kamen , Boiadjiev George , Kawasaki Haruhisa , Mouri Tetsuya
Published: November 2014

This paper deals with the improvement of the stability of sampled-data (SD) feedback control for nonlinear multiple-input multiple-output time varying systems, such as robotic manipulators, by incorporating an off-line model based nonlinear iterative learning controller. The proposed scheme of nonlinear iterative learning control (NILC) with SD feedback is applicable to a large class of robots because the sampled-data feedback is required for model based feedback controllers, especially for robotic manipulators with complicated dynamics (6 or 7 DOF, or more), while the feedforward control from the off-line iterative learning controller should be assumed as a continuous one. The robustness and convergence of the proposed NILC law with SD feedback is proven, and the derived sufficient condition for convergence is the same as the condition for a NILC with a continuous feedback control input. With respect to the presented NILC algorithm applied to a virtual PUMA 560 robot, simulation results are presented in order to verify convergence and applicability of the proposed learning controller with SD feedback controller attached
Comparison of Methane Drainage Methods Used in Polish Coal Mines
Authors: Szlązak Nikodem , Borowski Marek , Obracaj Dariusz , Swolkień Justyna , Korzec Marek
Published: November 2014

Methane drainage is used in Polish coal mines in order to reduce mine methane emissions as well as to keep methane concentration in mine workings at safe levels.

This article describes methods of methane drainage during mining used in Polish coal mines. The first method involves drilling boreholes from tailgate roadway to an unstressed zone in roof or floor layers of a mined seam. It is the main method used in Polish mining, where both the location of drilled boreholes as well as their parameters are dependent on mining and ventilation systems of longwalls. The second method is based on drilling overlying drainage galleries in seams situated under or over the mined seam.

This article compares these methods with regard to their effectiveness under mining conditions in Polish mines. High effectiveness of methane drainage of longwalls with different ventilation and methane drainage systems has been proven. The highest effectiveness of methane drainage has been observed for the system with overlying drainage gallery and with the parallel tailgate roadways. In case of classic U ventilation system of longwall panel, boreholes drilled from the tailgate roadway behind the longwall front are lost.
Predictive Regression Models of Monthly Seismic Energy Emissions Induced by Longwall Mining
Authors: Jakubowski Jacek , Tajduś Antoni
Published: November 2014

This article presents the development and validation of predictive regression models of longwall mining-induced seismicity, based on observations in 63 longwalls, in 12 seams, in the Bielszowice colliery in the Upper Silesian Coal Basin, which took place between 1992 and 2012. A predicted variable is the logarithm of the monthly sum of seismic energy induced in a longwall area. The set of predictors include seven quantitative and qualitative variables describing some mining and geological conditions and earlier seismicity in longwalls. Two machine learning methods have been used to develop the models: boosted regression trees and neural networks. Two types of model validation have been applied: on a random validation sample and on a time-based validation sample.

The set of a few selected variables enabled nonlinear regression models to be built which gave relatively small prediction errors, taking the complex and strongly stochastic nature of the phenomenon into account. The article presents both the models of periodic forecasting for the following month as well as long-term forecasting.
The Use of Fuzzy Systems in the Designing of Mining Process in Hard Coal Mines
Authors: Brzychczy Edyta , Kęsek Marek , Napieraj Aneta , Sukiennik Marta
Published: November 2014

This article presents examples of solutions supporting the design of certain elements of the mining process in coal mines. The focus is on two fuzzy systems: the first supports the selection of equipment for longwall faces (FSES); and the second supports the estimation of production results (FSOE). System FSES generates proposals for equipment in designed longwall faces. The module of fuzzing in this system enables a fuzzing operation for the following quantitative variables: longwall length; longwall height; longitudinal and crosswise incline of the longwall, workability of the coal and thickness of rock vein in a given section of the longwall. The knowledge base includes over 100 fuzzy rules indicating possible options for equipment under specified site conditions.

After a proposal of equipment is generated, it is then possible to insert the values obtained into the second system FSOE, which estimates output for a given shift time using the chosen parameters. The module of fuzzing in system FSOE includes 9 variables, which are crucial in determining shift output for the given longwall face. The knowledge base in this system contains over 2000 rules.

As a result of the operation of both systems, the designer receives both a proposal of equipment for the designed longwall face and the size of shift output under the given conditions.

Operation of the two systems has been presented using a case study.
Identification of the Oscillation Period of Chemical Reactors by Chaotic Sampling of the Conversion Degree
Authors: Lawnik Marcin , Berezowski Marek
Published: November 2014

To stabilise the periodic operation of a chemical reactor the oscillation period should be determined precisely in real time. The method discussed in the paper is based on adaptive sampling of the state variable with the use of chaotic mapping to itself. It enables precise determination of the oscillation period in real time and could be used for a proper control system, that can successfully control the process of chemical reaction and maintain the oscillation period at a set level. The method was applied to a tank reactor and tubular reactor with recycle.
Broadband Input Block of Radio Receiver for Software-Defined Radio Devices
Authors: Magnuski Mirosław , Surma Maciej , Wójcik Dariusz
Published: November 2014

In the paper a cost-effective input block of the SDR receiver for 0.9 — 2.4 GHz frequency band built of capacitive-tuned selective amplifier and broadband Vivaldi antenna is presented. The applied selective amplifier consists of three identical sections of tunable filters and two stages of monolithic broadband amplifiers. The single filter section proposed by the authors, due to its ability to absorb parasitic inductances of varicap diodes, simplifies usage of encapsulated varicap diodes in design of tunable in broad band selective filters dedicated to input stages of the receivers. Moreover, proposed filter section has small variation of in-band insertion loss in comparison to varicap-tuned filters built of coupled transmission lines which are commonly applied in input blocks of the microwave receivers. The described selective amplifier could be easily integrated on a single substrate with the Vivaldi antenna which is a cost effective way of fabrication of the tunable in broad band input block of a receiver that has desired gain, selectivity and directivity of the antenna.
Influence of Pumping Beam Width on Vecsel Output Power
Authors: Sokoł Adam K. , Sarzała Robert P.
Published: November 2014

The paper is devoted to a numerical analysis of an influence of a pumping beam diameter on output power of optically pumped vertical-external-cavity surface-emitting lasers. Simulations have been carried out for a structure with a GaInNAs/GaAs active region operating at 1.32 urn. Various assembly configurations have been considered. Results obtained show that laser power scaling is strongly affected by thermal properties of the device.
Modelling and Simulation of Normally-Off AlGaN/GaN MOS-HEMTs
Authors: Taube Andrzej , Sochacki Mariusz , Szmidt Jan , Kaminska Eliana , Piotrowska Anna
Published: November 2014

The article presents the results of modelling and simulation of normally-off AlGaN/GaN MOS-HEMT transistors. The effect of the resistivity of the GaN:C layer, the channel mobility and the use of high-k dielectrics on the electrical characteristics of the transistor has been examined. It has been shown that a low leakage current of less than 10−6 A/mm can be achieved for the acceptor dopant concentration at the level of 5 X 1015 cm−3. The limitation of the maximum on-state current due to the low carrier channel mobility has been shown. It has also been demonstrated that the use of HfO2, instead of SiO2, as a gate dielectric increases on-state current above 0.7A/mm and reduces the negative influence of the charge accumulated in the dielectric layer.
An Overview of Free Space Optics with Quantum Cascade Lasers
Authors: Mikołajczyk Janusz
Published: November 2014

The article presents an overview of the work on quantum cascade lasers application in free space optical systems (Free Space Optics - FSO). There are discussed the main issues of the open-space laser communications and their practical construction. Comparative analyses of each FSO technology were performed. Brief description of quantum cascade (QC) lasers and some developments related to the use of these lasers in optical data link are also presented. In summary, the constructed models of FSO links with QC lasers are characterized.
Extensions of Three Matrix Inequalities to Semisimple Lie Groups
Authors: Liu Xuhua , Tam Tin-Yau
Published: November 2014

We give extensions of inequalities of Araki-Lieb-Thirring, Audenaert, and Simon, in the context ofsemisimple Lie groups.
Singular M-matrices which may not have a nonnegative generalized inverse
Authors: Sushama Agrawal N. , Premakumari K. , Sivakumar K.C.
Published: November 2014

A matrix A ∈ ℝn×n is a GM-matrix if A = sI − B, where 0 < ρ(B) ≤ s and B ∈WPFn i.e., both B and Bthave ρ(B) as their eigenvalues and their corresponding eigenvector is entry wise nonnegative. In this article,we consider a generalization of a subclass of GM-matrices having a nonnegative core nilpotent decompositionand prove a characterization result for such matrices. Also, we study various notions of splitting of matricesfrom this new class and obtain sufficient conditions for their convergence.
Segregation of phosphorus to ferrite grain boundaries during transformation in an Fe–P alloy
Authors: Kim Jeong In , Pak Jun Hak , Park Kyong-Su , Jang Jae Hoon , Suh Dong-Woo , Bhadeshia Harshad Kumar Dharamshi Hansraj
Published: November 2014

A binary alloy of iron containing 0.17 wt.% of phosphorus has been heat treated under a variety of conditions in order to see whether the segregation of phosphorus to grain boundaries can be controlled. The alloy transforms fully into ferrite. It is found that the majority of solute found at the ferrite grain boundaries has its origins in the temperature range where phase transformation occurs, in other words, phosphorus that is accumulated and dragged with the growing ferrite–austenite transformation front. As a consequence, it cannot be suppressed using cooling rates as high as 400 K s−1.
Primary glioblastoma of the trigeminal nerve root entry zone: case report
Authors: Breshears Jonathan D. , Ivan Michael E. , Cotter Jennifer A. , Bollen Andrew W. , Theodosopoulos Phillip V. , Berger Mitchel S.
Published: November 2014

Gliomas of the cranial nerve root entry zone are rare clinical entities. There have been 11 reported cases in the literature, including only 2 glioblastomas. The authors report the case of a 67-year-old man who presented with isolated facial numbness and was found to have a glioblastoma involving the trigeminal nerve root entry zone. After biopsy the patient completed treatment with conformal radiation and concomitant temozolomide, and at 23 weeks after surgery he demonstrated symptom progression despite the treatment described. This is the first reported case of a glioblastoma of the trigeminal nerve root entry zone.
Cerebral paragonimiasis: a retrospective analysis of 27 cases
Authors: Xia Yong , Ju Yan , Chen Jing , You Chao
Published: November 2014

OBJECT

The authors retrospectively analyzed the clinical characteristics, existing problems, and treatment experiences in recently diagnosed cerebral paragonimiasis (CP) cases and sought to raise awareness of CP and to supply reference data for early diagnosis and treatment.

METHODS

Twenty-seven patients (22 male and 5 female; median age 20.3 years, range 4–47 years) with CP were diagnosed between September 2008 and September 2013. These diagnoses were confirmed by IgG enzyme-linked immunosorbent assays. Follow-up was performed in 24 cases for a period of 6–56 months.

RESULTS

Cerebral paragonimiasis accounted for 21.6% of paragonimiasis cases (27 of 125). The average duration from onset to praziquantel treatment was 69 days. All patients resided in rural areas. Twenty patients had positive lung results, which included visible lung lesions in 14 cases. The lesions were surgically removed in 8 of these cases. Twenty-four patients had high eosinophil counts (≥ 0.08 × 109/L), and eosinophilic meningitis was noted in 17 cases. The rate of misdiagnosis and missed diagnosis was 30.4%. Most symptoms were markedly improved after treatment, but mild movement disorders combined with impaired memory and personality changes remained in a small number of patients.

CONCLUSIONS

Clinicians should be alert to the possibility of CP in young patients (4–16 years) with the primary symptoms of epilepsy and hemorrhage. Early diagnosis and timely treatment can reduce the need for surgery and further impairments to brain function. Liquid-based cytological examination of CSF and peripheral blood eosinophil counts can aid in differentiating CP from similar lesions.
A modified Bohlman technique using a novel implant for treatment of high-grade spondylolisthesis
Authors: Hire Justin M. , Jacobs Jeremy M. , Bundy Justin V. , DeVine John G.
Published: November 2014

Several surgical options for managing high-grade spondylolisthesis have been described in the literature and range from posterior-only in situ fusion to circumferential fusion with complete reduction of the dislocation. The level of evidence supporting any one technique is weak, and to date there is no Level I or II evidence supporting any current surgical treatment option. Techniques have evolved as implant technology has advanced and surgeons have gained experience with deformity correction. Still, the paucity of cases at any one institution limits the ability to perform clinical studies in a prospective and randomized fashion. To the authors' knowledge, the use of the AxiaLif bolt in a modified Bohlman technique has not been described. In the setting of a case of symptomatic high-grade spondylolisthesis refractory to nonoperative management, the authors describe a modified Bohlman technique in which they used the AxiaLif bolt rather than the fibula graft that was originally described. They then supplemented this with pedicle screw instrumentation and an iliac crest autograft. At the 2-year follow-up exam, the patient exhibited relief of his preoperative back and leg pain and he had returned to all activities. The latest radiographs demonstrated successful fusion. A single-stage, posterior instrumented fusion in which the AxiaLif bolt is used in lieu of fibula autograft or allograft in a modified Bohlman technique is technically less demanding, does not have the morbidity associated with harvesting a fibula autograft, and carries no risk of disease transmission associated with the use of allograft.
Spinal stimulator peri-electrode masses: case report
Authors: Scranton Robert A. , Skaribas Ioannis M. , Simpson Richard K.
Published: November 2014

The authors describe a case of delayed spastic quadriparesis caused by a peri-electrode mass following the implantation of a minimally invasive percutaneous spinal cord stimulator (SCS). Prior reports with paddle-type electrodes are reviewed, and a detailed histological and pathophysiological comparison with the present case is made.

The patient developed tolerance to a cervical percutaneous SCS 4 months after implantation, followed by the onset of spastic quadriparesis 9 months after implantation. The stimulator was removed, and contrast-enhanced MRI revealed an enhancing epidural mass where the system had been placed, with severe spinal cord compression. Decompression was carried out, and the patient experienced neurological improvement. Pathological examination revealed fibrotic tissue with granulomatous and multinucleated giant cell reactions. No evidence of infection or hemorrhage was found. Professionals treating patients with SCSs or contemplating their insertion should be aware of this delayed complication and associated risk factors.
Evaluation of monoenergetic imaging to reduce metallic instrumentation artifacts in computed tomography of the cervical spine
Authors: Komlosi Peter , Grady Deborah , Smith Justin S. , Shaffrey Christopher I. , Goode Allen R. , Judy Patricia G. , Shaffrey Mark , Wintermark Max
Published: November 2014

OBJECT

Monoenergetic imaging with dual-energy CT has been proposed to reduce metallic artifacts in comparison with conventional polychromatic CT. The purpose of this study is to systematically evaluate and define the optimal dual-energy CT imaging parameters for specific cervical spinal implant alloy compositions.

METHODS

Spinal fixation rods of cobalt-chromium or titanium alloy inserted into the cervical spine section of an Alderson Rando anthropomorphic phantom were imaged ex vivo with fast-kilovoltage switching CT at 80 and 140 peak kV. The collimation width and field of view were varied between 20 and 40 mm and medium to large, respectively. Extrapolated monoenergetic images were generated at 70, 90, 110, and 130 kiloelectron volts (keV). The standard deviation of voxel intensities along a circular line profile around the spine was used as an index of the magnitude of metallic artifact.

RESULTS

The metallic artifact was more conspicuous around the fixation rods made of cobalt-chromium than those of titanium alloy. The magnitude of metallic artifact seen with titanium fixation rods was minimized at monoenergies of 90 keV and higher, using a collimation width of 20 mm and large field of view. The magnitude of metallic artifact with cobalt-chromium fixation rods was minimized at monoenergies of 110 keV and higher; collimation width or field of view had no effect.

CONCLUSIONS

Optimization of acquisition settings used with monoenergetic CT studies might yield reduced metallic artifacts.
Two-level total disc replacement with Mobi-C cervical artificial disc versus anterior discectomy and fusion: a prospective, randomized, controlled multicenter clinical trial with 4-year follow-up results
Authors: Davis Reginald J. , Nunley Pierce Dalton , Kim Kee D. , Hisey Michael S. , Jackson Robert J. , Bae Hyun W. , Hoffman Gregory A. , Gaede Steven E. , Danielson Guy O. , Gordon Charles , Stone Marcus B.
Published: November 2014

OBJECT

The purpose of this study was to evaluate the safety and effectiveness of 2-level total disc replacement (TDR) using a Mobi-C cervical artificial disc at 48 months' follow-up.

METHODS

A prospective randomized, US FDA investigational device exemption pivotal trial of the Mobi-C cervical artificial disc was conducted at 24 centers in the US. Three hundred thirty patients with degenerative disc disease were randomized and treated with cervical total disc replacement (225 patients) or the control treatment, anterior cervical discectomy and fusion (ACDF) (105 patients). Patients were followed up at regular intervals for 4 years after surgery.

RESULTS

At 48 months, both groups demonstrated improvement in clinical outcome measures and a comparable safety profile. Data were available for 202 TDR patients and 89 ACDF patients in calculation of the primary endpoint. TDR patients had statistically significantly greater improvement than ACDF patients for the following outcome measures compared with baseline: Neck Disability Index scores, 12-Item Short Form Health Survey Physical Component Summary scores, patient satisfaction, and overall success. ACDF patients experienced higher subsequent surgery rates and displayed a higher rate of adjacent-segment degeneration as seen on radiographs. Overall, TDR patients maintained segmental range of motion through 48 months with no device failure.

CONCLUSIONS

Four-year results from this study continue to support TDR as a safe, effective, and statistically superior alternative to ACDF for the treatment of degenerative disc disease at 2 contiguous cervical levels.

Clinical trial registration no.: NCT00389597 (clinicaltrials.gov)
Petroclival meningiomas resected via a combined transpetrosal approach: surgical outcomes in 60 cases and a new scoring system for clinical evaluation
Authors: Morisako Hiroki , Goto Takeo , Ohata Kenji
Published: November 2014

OBJECT

Petroclival meningiomas are among the most challenging intracranial tumors to treat surgically. Many skull base approaches have been described to improve resection and decrease patient morbidity. The authors undertook this study to evaluate the results of their treatment of petroclival meningiomas using objective measurements of tumor volume and a new impairment scoring system to assess neurological symptoms that severely affect the patient's quality of life, such as impairment of swallowing and speaking, motor function, and consciousness and communication.

METHODS

Between January 1990 and December 2009, the authors used a combined transpetrosal approach to treat 60 patients with benign (WHO Grade I) petroclival meningiomas. In this retrospective study, all 60 cases were analyzed in detail with regard to tumor volume, extent of resection (EOR), long-term tumor control, neurological outcome, and the patient condition. In addition, patients were divided into 2 groups according to the period during which the surgery was performed: the early group, from 1990 to 1999, and the late group, from 2000 to 2009. A new scoring system, the petroclival meningioma impairment scale (PCMIS), was created for quantitative assessment of 8 categories of neurological functions, with scores assigned in each category according to the level of disability and its impact on the patient. The PCMIS was used preoperatively, at 3 months after surgery, and at the time of the last follow-up examination, and the results for the 2 groups were compared.

RESULTS

There were 24 cases in the early group (1990–1999), and the mean duration of follow-up was 149.3 months. The mean EOR was 96.1%, and good long-term tumor control was obtained in 22 patients (91.7%). One of patients died because of a postoperative complication in the perioperative period. The PCMIS improved in 3 patients (12.5%), remained stable in 1 (4.2%), and worsened in 20 (83.3%). There were 36 cases in the late group (2000–2009), and the mean duration of follow-up was 77.9 months. The mean EOR was 92.7%, and good long-term tumor control was obtained in 34 patients (94.4%). The PCMIS score improved in 23 patients (63.9%), remained stable in 5 (13.9%), and worsened in 8 (22.2%).

CONCLUSIONS

The combined transpetrosal approach has provided satisfactory functional improvements and excellent tumor control for patients with petroclival meningiomas. The PCMIS provides a specific tool for quantitative assessment of the patient's state.
Hyperprolactinemia due to spontaneous intracranial hypotension
Authors: Schievink Wouter I. , Nuño Miriam , Rozen Todd D. , Maya M. Marcel , Mamelak Adam N. , Carmichael John , Bonert Vivien S.
Published: November 2014

OBJECT

Spontaneous intracranial hypotension is an increasingly recognized cause of headaches. Pituitary enlargement and brain sagging are common findings on MRI in patients with this disorder. The authors therefore investigated pituitary function in patients with spontaneous intracranial hypotension.

METHODS

Pituitary hormones were measured in a group of 42 consecutive patients with spontaneous intracranial hypotension. For patients with hyperprolactinemia, prolactin levels also were measured following treatment. Magnetic resonance imaging was performed prior to and following treatment.

RESULTS

The study group consisted of 27 women and 15 men with a mean age at onset of symptoms of 52.2 ± 10.7 years (mean ± SD; range 17–72 years). Hyperprolactinemia was detected in 10 patients (24%), ranging from 16 ng/ml to 96.6 ng/ml in men (normal range 3–14.7 ng/ml) and from 31.3 ng/ml to 102.5 ng/ml in women (normal range 3.8–23.2 ng/ml). In a multivariate analysis, only brain sagging on MRI was associated with hyperprolactinemia. Brain sagging was present in 60% of patients with hyperprolactinemia and in 19% of patients with normal prolactin levels (p = 0.02). Following successful treatment of the spontaneous intracranial hypotension, hyperprolactinemia resolved, along with normalization of brain MRI findings in all 10 patients.

CONCLUSIONS

Spontaneous intracranial hypotension is a previously undescribed cause of hyperprolactinemia. Brain sagging causing distortion of the pituitary stalk (stalk effect) may be responsible for the hyperprolactinemia.
Outcome methods used in clinical studies of Chiari malformation Type I: a systematic review
Authors: Greenberg Jacob K. , Milner Eric , Yarbrough Chester K. , Lipsey Kim , Piccirillo Jay F. , Smyth Matthew D. , Park Tae Sung , Limbrick David D.
Published: November 2014

OBJECT

Chiari malformation Type I (CM-I) is a common and often debilitating neurological disease. Efforts to improve treatment of CM-I are impeded by inconsistent and limited methods of evaluating clinical outcomes. To understand current approaches and lay a foundation for future research, the authors conducted a systematic review of the methods used in original published research articles to evaluate clinical outcomes in patients treated for CM-I.

METHODS

The authors searched PubMed, Embase, the Cumulative Index to Nursing and Allied Health Literature, ClinicalTrials.gov, and Cochrane databases to identify publications between January 2003 and August 2013 that met the following criteria: 1) reported clinical outcomes in patients treated for CM-I; 2) were original research articles; 3) included at least 10 patients or, if a comparative study, at least 5 patients per group; and 4) were restricted to patients with CM-I.

RESULTS

Among the 74 papers meeting inclusion criteria, there was wide variation in the outcome methods used. However, all approaches were broadly grouped into 3 categories: 1) “gestalt” impression of overall symptomatic improvement (n = 45 papers); 2) postoperative change in specific signs or symptoms (n = 20); or 3) results of various standardized assessment scales (n = 22). Among standardized scales, 11 general function measures were used, compared with 6 disease-specific tools. Only 3 papers used scales validated in patients with CM-I. To facilitate a uniform comparison of these heterogeneous approaches, the authors appraised articles in multiple domains defined a priori as integral to reporting clinical outcomes in CM-I. Notably, only 7 articles incorporated patient-response instruments when reporting outcome, and only 22 articles explicitly assessed quality of life.

CONCLUSIONS

The methods used to evaluate clinical outcomes in CM-I are inconsistent and frequently not comparable, complicating efforts to analyze results across studies. Development, validation, and incorporation of a small number of disease-specific patient-based instruments will improve the quality of research and care of CM-I patients.