bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical Properties Including Fatigue of CP Ti and Ti-6Al-4V Alloys Fabricated by EBM Additive Manufacturing Method
Authors: Choi Young Sin , Kim Chang Lim , Kim Gun Hee , Lee Byoung Soo , Lee Chang Woo , Lee Dong Geun
Published: November 2017

The Electron Beam Melted (EBM) method is one of the attractive attention thing additive manufacturing methods. By using an EBM additive manufacturing method, CP Ti and Ti-6Al-4V specimen were fabricated with a certain processing parameters. The mechanical properties such as fatigue limit, tensile properties including microstructural characteristics of CP Ti and Ti-6Al-4V specimens fabricated by EBM were confirmed and were compared with the conventional Ti alloys. Additive manufacturing was obtained high strength by creating martensite due to rapid cooling. On the other hand, void occurrence cannot be avoided by the method of using powder, accordingly it had a low fatigue strength value. Therefore, this study focused on that the values of fatigue characteristics of the EBM specimens and conventional specimens were compared and analyzed. EBM CP Ti had good mechanical properties such as yield strength, ultimate tensile strength, elongation and fatigue limits, approximately as same as casting CP Ti. EBM Ti-6Al-4V showed good mechanical properties, but fatigue limits were lower than wroughtTi-6Al-4V. That resulted from the formation of several kinds of internal pores which caused to increase the crack initiation and propagation.
Effects of Sintering Temperature on the Mullite-Based Ceramics Fabricated from Rice Husk Ash
Authors: Abdul Wahab Rabiatul Adawiyah , Yahya Mohd Ashmir , Matori Khamirul Amin , Ghani Wan Azlina Wan Abdul Karim
Published: November 2017

Mullite-based ceramics were prepared by utilizing agriculture by-product called as rice husk ash (RHA) from untreated rice husk (RH) and commercial alumina powdermixtures. Various samples were prepared accordingly with the mullite stoichiometric composition and subjected to the uniaxial hydraulic press. The green bodies, then were sintered to various temperatures at 1200 °C, 1300 °C, 1350 °C, 1400 °C, 1450 °C and 1500 °C in an electric furnace. Physical and microstructural characterization were done such as bulk density (BD), linear shrinkage (LS), X-ray fluorescence (XRF), X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). The sample M1, which composed the slightest RHA (40 %) was considered the optimum composition which produced the highest densification, 3.101 g/cm3 and the lowest linear shrinkage, 8.62 % which compareswith the theoretical mullite density. Besides, it is supported by the evidence of the presenceof mullite in the samples sintered 1300 °C (shown as elongated shape) as primary mullite and continued to grow at higher temperatures at 1400 °C (shown as equiaxed shape) as secondary mullite. The sintered samples showno evidence of mullite inearly at 1200 °C due to insufficient energy to diffuse for mullitization. As the sintering temperature increased, mullitization increased while decreasing the distribution of glassy phase and voids. The results revealed the high dependency of bulk density and linear shrinkage on the Al2O3 content and the values were gradually increased with the increase of sintering temperature. These findingsmay lead to the extended study ofthermal insulationmaterials as mullite ceramic is an excellent candidate for this application due to its properties.
Influence of Gama Prime Changes on the Heat Transport Phenomena of a Nickel Super Alloy
Authors: Koštial Pavel , Jonšta Petr , Kopal Ivan , Koštialová Jančíková Zora , Špička Ivo , Kulová Taťána , Vlčková Irena
Published: November 2017

The paper deals with the influence of microstructural changes of the nickel superalloy (NiS) on heat transport changes in MAR-M247. The dissolving annealing within the temperature interval of 900 – 1240°C and cooling in water has been applied to enhance structural changes. It has been shown that the narrow connection between the γ’ phase morphology changes, as well as values of density, thermal conductivity and specific heat capacity. In the dissolving annealing process, the γ’ particles change in certain cycles from fine to rough and back to fine one. Obtained results of changes of thermal conductivity, density and specific heat capacity correlate with image analysis and electron microscopy observation.
Considerations on Heat Transfer in Parallel-Plate Channels with Staggered Fins
Authors: Perão L.H. , Vaz Jr. Miguel , Zdanski Paulo S.B.
Published: November 2017

This work addresses heat transfer in channels fitted with heat-conducting fins inserted in both walls, transversally to the flow direction, in a staggered arrangement. Turbulent fluid flow and conjugate heat transfer are assumed in the simulations. The hydrodynamic (pressure coefficient) and thermal (Nusselt number) behavior of the heat exchanger is investigated for different values of fin thickness, inclination angle and blockage ratio. The simulations show that the geometrical parameters of the finned channel cause changes in the flow topology, which in turn leads to significant differences in pressure drop and heat transfer rate. It is observed that the fin blockage ratio imposes the greatest effect in the hydrodynamic and thermal problems, followed by the fin inclination angle and thickness.
Moisture Diffusion in Natural Rubber/Bentonite Nanocomposites: Effect of Clay Filler Treatments
Authors: Pajarito Bryan B. , Mangaccat Winna Faye F. , Tigue Maelyn Rose M. , Tipton Monica T.
Published: November 2017

This study investigated the effects of clay filler treatments on moisture diffusion in natural rubber (NR)/bentonite nanocomposites. Four types of clay filler treatments were considered: sodium activation using sodium chloride (NaCl), ion exchange using hexadecyldimethylamine (HDA) chloride salt, modification using coco diethanolamide (CDEA), and wet grinding using ethanol as medium. A 24 full factorial design of experiment (DOE) was utilized during clay filler treatments. The measured vulcanization characteristics of rubber specimens show the NR nanocomposites to be stiffer than unfilled NR, with very small differences in scorch and curing times. The moisture uptake of rubber specimens at 80°C is linear with square root of immersion time showing Fickian behavior. The rate of moisture uptake (slope of moisture uptake versus square root time) was measured. Determination of factor effects and analysis of variance show all clay filler treatments except for wet grinding significantly increase the rate of moisture uptake of NR nanocomposites. When compared to unfilled NR, only wet grinding of clay is found effective in lowering moisture diffusion.
Correlation between the Energy Input and the Microstructure of Additively Manufactured Cobalt-Chromium
Authors: Hitzler Leonhard , Williams Philipp , Merkel Markus , Hall Wayne , Öchsner Andreas
Published: November 2017

Powder-bed based additive manufacturing techniques are of high interest for the medical sector and recent trial studies have shown their feasibility. Due to the rapid improvements made in the machinery and the related changes in the type and characteristics of the utilized power source, optimizations regarding the fabrication parameters tend to differ amongst various machines. In this study, a parameter optimization was undertaken for a biocompatible dental CoCrMo alloy on a SLM 280HL machine, featuring a 400 W fibre laser. It was shown that the availability of higher laser powers enables a more energy efficient fabrication. Moreover, parameter sets for fast and economic fabrication, as well as for high density and fine-grained microstructure, were defined.
Pressure Model for Capillary Tree-Shaped Fractal Networks
Authors: Miguel Antonio Ferreira
Published: November 2017

Capillary tree networks can be efficiently used for several applications. These trees display the same patterns at different levels of scale, which is a property found in fractal objects. This paper combines a thermodynamic formulation with the geometric characteristics of the tree fractal network, to describe the equilibrium capillary pressure. The model proposed here accounts for, in addition to physical properties of the fluids, the fractal dimension, the scale factor between the size of parent and daughter tubes, and the branching level. The effect of each of these properties on the capillary pressure is also investigated.
Antibiotic Containing Poly Lactic Acid/Hydroxyapatite Biocomposite Coatings for Dental Implant Applications
Authors: Karacan Ipek , Macha Innocent Jacob , Choi Gina , Cazalbou Sophie , Ben-Nissan Besim
Published: November 2017

The biodegradable and biocompatible antibiotic containing thin film composites are very appropriate biomaterials as coating materials for dental implants because of their adjustable drug loading and release rates for the prevention of implant related infections. Coralline hydroxyapatite (HAp) was loaded with gentamicin antibiotics and combined with a biodegradable polylactic acid (PLA) to form thin film composites. PLA-HAp, PLA-Gentamicin (GM) and PLA-HAp-GM composites were produced, and their dissolution studies were carried out in phosphate buffered saline under SINK conditions. It was observed that the coatings could be efficiently applied to titanium dental implants and the drug release rates can be efficiently controlled.
Preparation and Evaluation of Calcium Sulfate/Collagen Composite Pellets
Authors: He Xu Zhao , Zhuang Jun Jun , Cheng Kui , Weng Wen Jian
Published: November 2017

Calcium sulfate/type I collagen composite pellets were prepared by a feasible route of casting method. The as-prepared composite pellets were characterized and the results showed that the collagen fibrils acted as bridges to connect the adjacent calcium sulfate grains, especially when there was a high mass loading of collagen, which effectively depressed the rapid degradation of the pellets and improved compressive strength, and the optimal strength reached 17.2 MPa with 6 mg/mL collagen solution. The MC3T3-E1 cells could be well attached and spread on the surface of the composite pellets. Moreover, it is found that the collagen be released through pellets degradation further promoted the cells proliferation.
Foam-Based Bionanocomposite Scaffold for Bone Tissue Engineering
Authors: Quemeneur Fany , Tourne-Peteilh Corine , Drouet Christophe , Dupret-Bories Agnès , Tourrette Audrey , Begu Sylvie , Girod Fullana Sophie
Published: November 2017

The repair of large bone defects is a major clinical problem for which tissue engineering (association of a biomaterial and cells) constitutes a valuable alternative. In this domain, the architecture and the mechanical properties of the 3D scaffold aimed to support cells is of key importance to succeed in bone reconstruction. In this study, we aim to design and evaluate a bionanocomposite foam-based scaffold, exhibiting all the desired biofunctional attributes of biocompatibility, bioactivity, osteoconduction/induction, combined with potential release properties. To perform this, 2 components have been associated: (i) a biopolymer, pectin, incorporating (ii) calcium phosphate nanoparticules to provide bone apatite nucleation sites, mechanical reinforcement, and to play the role of potential drug reservoir. The goal of this study was to determine the feasibility of obtention of such bionanocomposite by foam-templating, and to study the influence of mineral particules ratio on pectin foam and final scaffold 3D architecture and properties.
TEM Observation of Heat-Treated β-Tricalcium Phosphate Powder and its Precursor Obtained by Mechanochemical Reaction
Authors: Shishido Atsumasa , Yokogawa Yoshiyuki
Published: November 2017

Mechanical and biological functions of b-tricalcium phosphate (b-TCP) ceramics is of importance with respect to medical application such as bone graft substitute. The degrees of crystallynity and morphology of as-prepared b-TCP powders are concerned with the above functions. Mechanochemical synthesis is a process of producing a fine particle of b-TCP through an intermediate phases (precursor) of calcium phosphate. The b-TCP precursor synthesized by mechanochemical reaction, followed by heat-treatment, was analysed by using transmission electron microscopy, X-ray diffraction and Fourier transformation infrared spectroscopy. The hydrate layer and carbonate ions involved in the precursor were found to affect the degrees of crystallinity and morphology of as-prepared b-TCP particles at a certain temperature, 700 °C. The specific characteristics of crystallinity and morophology of as-prepared b-TCP particle is expected to be favorble to forming and sintering of b-TCP ceramics.
Physicochemical Characterization of Nano-Hydroxyapatite Prepared by a Wet Method
Authors: Xu Jia Yun , Kasugai Shohei , Aoki Hideki , Terukina Takayuki , Otsuka Makoto
Published: November 2017

Recently nano-hydroxyapatite (nano-HA) has been used as a new biomaterial in medical and dental fields. There are many methods to synthesize the nano-HA. In the present study, the nano-HA was synthesized under various reaction conditions by a wet method using neutralization reaction of calcium hydroxide suspension and phosphoric acid solution. The physicochemical properties of the nano-HA were characterized by XRD, FTIR, TG and TEM. The XRD, FTIR and TEM results indicated that the nano-HA samples were pure and the sizes were less than 50 nm. However, all samples contained carbonate and the contents were determined to be 2-4% by TG. The crystallinity of the nano-HA increased higher at body temperature of 37°C than at lower temperature of 7-10°C.
Bioactive Glasses in Treating Bone Infections
Authors: Lupescu Olivera , Nagea Mihail , Dimitriu Alexandru , Antoniac Iulian Vasile
Published: November 2017

Bone infections are challenging due to their difficult and prolonged treatment, considerable possibility of relapse and strong negative physical and emotional impact. Since their treatment require thorough excisions, bone substitutes have been studied for restoring bone continuity, but with limited efficacy due to the pathophysiology of bone infections; one of the classes which proved to be efficient were the BioActive Glasses [BAG], synthetic biocompatible inorganic materials with a controlled ionic release, with demonstrated properties of wound healing, osteoconduction, angiogenesis and antibacterial activity. This paper presents the clinical experience from a Level 1 Trauma Centre where post-traumatic osteitis was treated using BioActive Glasses as bone fillers, demonstrating the potential clinical impact of these materials. The outcome of the patients was favourable, with no relapse of sepsis, therefore proving the efficacy of BAG in cases with limited grafting possibilities
Preliminary Study for Co-Culture of Osteoblasts and Endothelial Cells to Construct the Regenerative Bone
Authors: Honda Michiyo , Aizawa Mamoru
Published: November 2017

Vascularization is a crucial process during bone development and regeneration. A number of studies have shown that the interaction between osteoblasts and endothelial cells plays a key role in osteogenesis by using co-culture system. However, vascularization strategies in cell-based bone tissue engineering depend on optimal culture conditions. In this study, we determined the optimal co-culture conditions in view of osteogenic parameters and examined the effects of angiogenic properties on osteogenesis. As for cell proliferation, the proportion of osteoblasts increased and that of endothelial cells decreased as culture period passed. Assessment of osteogenic differentiation shows that co-culture of osteoblasts and endothelial cells significantly increased alkaline phosphatase activity and expression of bone-related genes. Furthermore, abundant microcapillary-like structures were observed which endothelial cells self-assembled into branches and net-like structures. The use of endothelial cells would be a promising strategy to promote vascularization to support the bone regeneration. Combination of these cell-based approaches and tissue engineering like three-dimensional scaffolds could provide a novel treatment therapy for bone defects and bone diseases.
Preparation and Characterization of Novel Bioceramic Coatings on Ti6Al4V Substrates for Biomedical Applications
Authors: Grima Lorena , Peña J.I. , Pardo José A.
Published: November 2017

With age bones lose quality being in some cases necessary their replacement. Research is underway on the development of biomaterials to meet the mechanical and biological requirements. One of the most used alloys is Ti6Al4V. The disadvantage of this biomaterial is the formation of a layer of connective tissue between the implant and the surrounding tissue, which makes it difficult to attach to living bone. Ceramic coatings are made on the surface of these metal biomaterials, which improve the communication between the implant and the living tissue.Ti6Al4V substrates have been coated with a bioactive ceramic with composition 7CaO.P2O5.2SiO2 by Pulsed laser deposition (PLD). Layers have been deposited under different substrate conditions and their microstructure and composition have been characterized by XRD and SEM.
Control of HAp Formation and Osteoconductivity on Nitrogen-Doped TiO2 Scale Formed by Oxynitridation of Ti
Authors: Hashimoto Masami , Kitaoka Satoshi , Obata Yoshihiro , Muto Shunsuke , Ogawa Takafumi , Furuya Maiko , Kanetaka Hiroyasu
Published: November 2017

The surface potential of the TiO2 scale formed on Ti was controlled by varying the Ti heat treatment conditions in a N2 atmosphere containing a trace amount of O2. The surface potential was attributed to the effective charge of nitrogen-related defects in the TiO2, where the positive and negative surface charges were associated with (N2)0+2 and (NO)0-1, respectively. The latter defects were formed only during the early stages of the heat treatment, and with increasing treatment time, this was followed by the formation of voids containing N2 in the scale rather than the disappearance of the defects in the TiO2 crystal lattice, resulting in zero surface charge. Hydroxyapatite (HAp) formation and osteoconductivity were enhanced on nitrogen-doped TiO2 scale with either a positive or negative surface potential. In contrast, for the unchanged TiO2 scale, no HAp formation was observed and the osteoconductivity was low.
Venous Sinus Stenting using Transcranial Access for the Treatment of Idiopathic Intracranial Hypertension in a Pediatric Patient
Authors: Buell Thomas J. , Starke Robert M. , Ding Dale , Hixson Harry R. , Raper Daniel M. S. , Chen Ching-Jen , Liu Kenneth C.
Published: November 2017

A 4-year-old male with headaches, papilledema, intracranial hypertension, and bilateral transverse sinus (TS) stenosis underwent attempted percutaneous placement of a right TS stent. Stent deployment was not technically feasible due to the stiffness of the stent and tortuosity of the patient's jugular bulb. Therefore, the patient underwent hybrid endovascular stenting of the right TS using neuronavigation and direct access of the TS following a single burr hole craniectomy. Two Express 8 mm × 17 mm balloon-mounted stents were deployed into the right TS, which resulted in obliteration of the preexisting trans-stenosis pressure gradient and decreased intracranial parenchymal pressure as monitored through an intracranial pressure bolt. The patient's headaches and papilledema resolved, and follow-up imaging demonstrated no in-stent or stent-adjacent stenosis. This case demonstrates the feasibility of combining minimally invasive open surgical access to allow direct cannulation for venous sinus stenting.
Role of Biomarkers in Differentiating New-onset Seizures from Psychogenic Nonepileptic Seizures
Authors: Javali Mahendra , Acharya Purushottam , Shah Shripal , Mahale Rohan , Shetty Pushparaja , Rangasetty Srinivasa
Published: November 2017

Introduction: Review of literature revealed very limited studies considering a combination of serum prolactin (PRL) and serum creatine kinase (CK) as markers for differentiating epileptic and psychogenic nonepileptic seizures (PNES). Therefore, in the present study, we analyzed the role of serum PRL and serum CK, individually and in combination. Methodology: This prospective study was conducted in a tertiary care medical teaching hospital over a period of 18 months. Patients aged over 15 years suspected to have new-onset seizures presenting within 5 h of ictus were included in this study. CK, serum PRL was measured at 0–1, 1–3, and 3–5 h after seizures. Results: Hundred subjects were studied for the role of serum PRL and serum CK in differentiating epileptic and PNES. The mean age was 42.24 years with a male:female ratio of 1.27:1. All patients of generalized tonic–clonic seizures (GTCS), who presented within 1 h, had elevated PRL, whereas 75% of patients with partial seizures had elevated PRL within 1 h of presentation. Nearly 91.66% of patients with GTCS who presented within 1 h had elevated CPK, whereas 70% of patients with partial seizures had elevated CPK. None of the patients diagnosed with PNES showed rise in either of the markers. Conclusion: In the present study, none of the patients with PNES showed raise in either serum PRL or CK. However, there was no correlation between the types of seizure and PRL or serum CK levels.
Usefulness of Pulsed Arterial Spin Labeling Magnetic Resonance Imaging in New.onset Seizure Patients and Its Comparison with Dynamic Susceptibility Contrast Magnetic Resonance Imaging
Authors: Bansal Varun , Kumar Suresh , Sharma Sudhir , Sharma Sanjiv , Sood R. G.
Published: November 2017

Introduction: Dynamic susceptibility contrast (DSC) perfusion and pulsed arterial spin labeling (PASL) imaging are newer advanced magnetic resonance sequences which are capable of detecting vascular changes in patients with new-onset seizure disorder even when no significant abnormalities are visualized on conventional sequences. The purpose of our study is to establish utility of arterial spin labeling (ASL) in new-onset seizure patients and compare ASL with DSC perfusion sequence. Materials and Methods: Twenty-six patients coming to emergency department with new-onset seizure disorder were evaluated using DSC and ASL sequence. Perfusion asymmetry was assessed using region of interests taken at places where signal asymmetry was maximal. Results: PASL sequence showed focal vascular changes in form of hyperperfusion in four patients, hypoperfusion in nine patients, and normal perfusion in 13 patients. Altered perfusion whether hypo/hyperperfusion was detected in five out of 16 patients even when conventional sequences were normal. There was strong positive linear correlation between ASL and DSC with P = 0.001. Conclusion: Noninvasive PASL is capable of detecting vascular changes induced by seizure and is comparable to DSC sequence. Thus, it is recommended when there is a need for repeated evaluations; in follow-up/therapy response assessment and when contrast administration is contraindicated.
Delayed Visual Loss Following Transcranial Surgery for Tuberculum Sella Meningioma
Authors: Menon Sudha , Menon Girish
Published: November 2017

Postoperative visual loss is a dreaded complication following transcranial excision of tuberculum sella meningioma. Visual deterioration is commonly noticed immediately after surgery, and delayed deterioration after 72 h is uncommon. We report a case of delayed postoperative deterioration in a 48-year-old female and discuss the possible mechanisms.
Trend of Neuropsychiatric Morbidity in Sub-Himalayan Region: An Audit of Retrospective Data Mining
Authors: Gandhi Manoj Kumar , Sharma Piyush , Singh Mitasha , Raina Sunil Kumar , Pal Ranabir
Published: November 2017

Background: There is a paradigm shift in health loss due to premature mortality and disability from neuropsychiatric disorders with major burden in low- and middle-income countries. Objective: To study the trend of admissions with neuropsychiatric and substance-use disorders in 3 years in psychiatry and medicine wards of tertiary care hospital in rural Himachal Pradesh. Methodology: A retrospective data mining was done from records of Inpatient wards of Dr. R. P. Government Medical College, Tanda, Himachal Pradesh, for the year 2013–2015. Demographic details and diagnosis of neuropsychiatric disorders, licit and illicit drug use, and their consequences in the form of hanging and poisoning were analyzed. Results: Majority of admissions were attributed to alcohol abuse which increased in 3 years significantly in the months of July–September (P = 0.02) and October–December (P = 0.00). Almost all cases of neuropsychiatric disorders and majority of poisoning (58.2%) were observed among females. The productive young and middle age group (21–40 years) was mostly affected by all cause neuropsychiatric disorders (80.9%) and presented with poisoning (66.2%). Illicit drug abuse was on increasing drift among females. Conclusion: Indoor admissions were attributed to alcohol use and poisoning while neuropsychiatric disorders and substance abuse were probably dealt with at outpatient level. Treatment pertaining to mental illnesses was sought in severe cases only. Data demonstrating population burden are needed urgently to address the barriers to treatment to reduce burden.
Subarachnoid Hemorrhage Due to Ruptured Intracranial Aneurysm Arising from a Vertebral Artery-Bihemispheric Posterior Inferior Cerebellar Artery Bifurcation
Authors: Ogasawara Yasushi , Kashimura Hiroshi , Aso Kenta , Saura Hiroaki
Published: November 2017

Although the anatomy of the posterior inferior cerebellar artery (PICA) is highly variable, a solitary PICA supplying both hemispheres of the cerebellum is rare. A 76-year-old woman presented with severe headache and subsequent loss of consciousness and was admitted to our hospital. Initial computed tomography showed subarachnoid hemorrhage. Three-dimensional digital subtraction angiography revealed a saccular aneurysm arising from the right vertebral artery (VA)-PICA bifurcation. The PICA branching from the right VA was enlarged, tortuous, and crossed the midline to supply both cerebellar hemispheres. This right PICA was interpreted as a bihemispheric PICA. Recognizing this variant preoperatively could help prevent complications of surgery. Careful follow-up studies are necessary in cases with bihemispheric PICA to monitor for the development of aneurysm at the junction between the bihemispheric PICA and the VA or the distal portion of the bihemispheric PICA.
Symptoms of Neurotoxicity among Carpenters Living in Rural Ecuador: A Population-based Study (The Atahualpa Project)
Authors: Del Brutto Oscar H. , Mera Robertino M. , de Amador Ani Reich , Zambrano Mauricio , Castillo Pablo R.
Published: November 2017

Background: There is no information on the prevalence of symptoms related to neurotoxicity among carpenters working in underserved populations. To assess the magnitude of the problem, we conducted a population-based study in Atahualpa, a rural Ecuadorian village, where most men work as carpenters under poor safety conditions. Methods: All men aged 40–75 years living in Atahualpa were identified during a door-to-door survey and evaluated with a general demographic questionnaire, the Q16 questionnaire, the depression axis of the Depression Anxiety Stress Scale-21, and the Montreal Cognitive Assessment (MoCA). Results: Among 230 participants, 63% were carpenters. Seventy participants (30%) had a positive Q16 questionnaire (≥6 points), which suggested neurotoxicity. In a logistic regression model adjusted for age, education, alcohol intake, symptoms of depression, and MoCA score, the proportion of Q16 positive persons was 39.1% for carpenters and 15.9% for noncarpenters (odds ratio: 3.53, 95% confidence interval: 1.75–7.15, P < 0.0001). In a generalized linear model, adjusted mean scores in the Q16 questionnaire were 4.9 for carpenters and 3.6 for noncarpenters (β: 1.285, standard error: 0.347, P < 0.0001). There was no correlation between scores in the Q16 questionnaire and the MoCA (Pearson correlation coefficient = −0.02), and the only significant covariate in the multivariate linear model was age, with every 10 years of age difference contributing 0.64 points in the Q16 questionnaire. Conclusion: This study shows a high prevalence of symptoms associated with neurotoxicity among carpenters after adjusting for a number of confounders. Long-term exposure to toxic solvents is the most likely explanation to this finding.
Chromosome 15 Duplication and Attention-Deficit Hyperactivity Disorder
Authors: Gnanavel Sundar
Published: November 2017

Chromosome 15 duplication has been associated with a number of psychiatric illnesses including psychosis and autism. However, literature on association with attention-deficit hyperactivity disorder (ADHD) is scant. This case report describes a patient with chromosome 15 duplication diagnosed with ADHD in our neurodevelopmental clinic. The possible biological underpinnings are discussed along with possible challenges in diagnosis and management. The need for better understanding ADHD as a behavioral phenotype in such cases along with need for tailored management strategies is emphasized.
Postepidural Spinal Intradural Arachnoid Cyst: A Rare Case Report
Authors: Umerani Muhammad Sohail , Mostafa Gabr Ahmed , F. Nada Mona A. , Darwish Amjad Abdel Qader
Published: November 2017

Compression of the neural structures in spine by an intradural arachnoid cyst is a rare entity. At times such a cyst is an incidental finding. Spinal epidural injection is one of the few rare etiological factors for its development. Symptomatic cysts can present with variable neurological manifestations depending on the spinal level involved. This includes back pain, lower limb weakness, and sphincteric dysfunction. If asymptomatic, they can be followed radiologically. Surgical decompression along with a histological diagnosis is reserved for cysts that are enlarging, symptomatic or the ones for whom the diagnosis is uncertain. Incomplete excision of cyst wall or simple fenestration and decompression mandates close follow-up, clinically and radiologically for further recurrences.
Behavioral Problems and Intelligence Quotient Changes in Pediatric Epilepsy: A Case–Control Study
Authors: Choudhary Shyama , Niranjan N. , Khichar Satyendra , Berwal Pramod K. , Barath Abhijeet Singh
Published: November 2017

Background: Epilepsy is the most common chronic neurological disease and has neurological impairment as an important comorbidity. Objective: To find behavioral problems and intelligence quotient (IQ) changes associated with epilepsy and to know the association of variables such as frequency, type of seizures, and duration of disease with cognitive impairment. Materials and Methods: A descriptive cross sectional study, consisting of 50 cases (patients of epilepsy) and 50 controls (other patients of same socioeconomic status) was conducted at S.P. Medical College, Bikaner. The patients were subjected to detailed clinical history, thorough examination, Pediatric Symptom Checklist, and Bhatia's Battery of Performance intelligence Test. Data analysis was carried out with the help of SPSS 22 software. Results: The prevalence of behavioral problems in generalized and partial seizure group was high (42% and 53.8%) as compared to control group (9%). Low IQ was present more in the patients (44%) of generalized and partial seizure group as compared with the control group, and results were statistically significant. Furthermore, behavioral problems were more in patients who were having more number of seizures (≥3 per year) with significant P values (χ2 = 5.067, P = 0.024). Conclusion: We conclusively found that behavioral problems and cognitive factors, apart from control of seizures, must be kept in mind to determine how well a child with epilepsy progresses toward independence.
On the isoperimetric profile for a mixed Euclidean–Log-convex measure
Authors: Fusco Nicola , Pallara Diego
Published: November 2017

We study the isoperimetric problem in

\mathbb R^h\times\mathbb R^k

endowed with a mixed Euclidean–Log-convex measure

\lambda=e^{\psi(x)}\, dxdy

. We prove the existence of an isoperimetric set and we show some of its qualitative properties.
The role of interplay between coefficients in the $G$-convergence of some elliptic equations
Authors: Boccardo Lucio , Orsina Luigi , Ponce Augusto C.
Published: November 2017

In [3] it is proved that, in some Dirichlet problems, the interplay between the coefficient of the lower order term and the right hand side yields a regularizing effect on the solution:

u

belongs to

{W_0^{1,2}(\Omega)\cap L^\infty}

even with a right hand side

f

belonging only to

L^1 (\Omega)

. In this paper we study the role of the interplay assumption under perturbation of the elliptic operator in the sense of the

G

-convergence.
A note on the Moser–Trudinger inequality in Sobolev–Slobodeckij spaces in dimension one
Authors: Iula Stefano
Published: November 2017

We discuss some recent results by Parini and Ruf on a Moser–Trudinger type inequality in the setting of Sobolev–Slobodeckij spaces in dimension one. We push further their analysis considering the inequality on the whole

\mathbb R

and we give an answer to one of their open questions.
Control de Tracción para un Vehículo Eléctrico basado en Observadores no Lineales
Authors: Aligia Diego A. , Magallán Guillermo A. , De Angelo Cristian H.
Published: November 2017

En este trabajo se propone una estrategia de control de tracción para un vehículo eléctrico de cuatro ruedas, basada en observadores no lineales que permiten estimar la fuerza máxima que se puede transferir al suelo. El conocimiento de la fuerza máxima permite realizar un control del deslizamiento de los neumáticos de tracción, evitando que las ruedas patinen aún en superficies de baja adherencia. La estrategia propuesta permite además evitar que se produzca un momento de guiño no deseado en el vehículo cuando las condiciones de suelo a cada lado del mismo son diferentes. Con ello se logra mejorar la eficiencia y el control del vehículo, evitando posibles pérdidas de estabilidad que pueden resultar en riesgos para sus ocupantes. Tanto el observador como el control propuestos son diseñados en base a un modelo dinámico rotacional de la rueda y un modelo de fuerzas de brush. Se presentan resultados de simulación obtenidos  empleando un modelo completo de vehículo sobre la plataforma Simulink/CarSim
Generación de Regiones con Potencial de Contener Peatones usando Reconstrucción 3D No Densa a partir de Visión Monocular
Authors: Zubiaguirre-Bergen Ignacio , Torres-Torriti Miguel , Flores-Calero Marco
Published: November 2017

Los accidentes de tráfico son un problema de salud pública a escala mundial, por el alto número de víctimas humanas y los elevados costos económicos y sociales que generan. En este contexto, los peatones se encuentran entre los elementos más importantes y vulnerables de la escena vial que necesitan ser protegidos. Es así que en este trabajo se presenta una innovadora propuesta utilizado la información visual monocular para emular la visión estéreo, y a partir de ello: i) generar regiones de interés (ROIs) con alta posibilidad de contener un peatón, y ii) estimar la trayectoria del vehículo. Los experimentos han sido desarrollados sobre una base de datos de imágenes tomadas en varias calles de la ciudad de Santiago (Región-Metropolitana), Chile. Esta información fue obtenida usando una plataforma experimental en condiciones reales de conducción durante el día. La tasa de detección de ROIs es del 86;6 % para distancias menores a 20 metros, 82;9 % para distancias menores a 30 metros y del 76;2 % para distancias menores a 40 metros.
UWSim, un simulador submarino conectado a la nube como herramienta educacional
Authors: Pérez Javier , Fornas David , Marín Raúl , Sanz Pedro J.
Published: November 2017

La creciente demanda social de nuevas aplicaciones de la robótica, desde robots domésticos a coches autónomos, confirma la conveniencia de utilizar dicha tecnología como factor motivante en el contexto educacional. Así, el presente trabajo analiza cómo canalizar esta motivación hacia fines productivos, poniendo el énfasis en las posibilidades que ofrecen los simuladores de robots submarinos. En particular, se propone un entorno de aprendizaje en la nube con un simulador capaz de evaluar al alumno como eje central del sistema. Utilizando este tipo de herramientas tan solo es necesario un dispositivo capaz de acceder a Internet a través de un navegador para alcanzar una cantidad virtualmente ilimitada de recursos. Como caso de estudio, se detallan las mejoras implementadas, en una aplicación de seguimiento de tuberías submarinas, creando un entorno de comparación en la nube que permite a los alumnos competir por obtener el mejor resultado posible. Finalmente, es importante destacar que se aporta una primera experiencia de aplicación en un contexto de enseñanza real de la herramienta propuesta, demostrándose la viabilidad e idoneidad de la misma para el aprendizaje de robótica y ROS.
Estabilización Automática de una Bicicleta sin Conductor mediante el Enfoque de Control por Rechazo Activo de Perturbaciones
Authors: Baquero-Suárez Mauro , Cortes-Romero John , Arcos-Legarda Jaime , Coral-Enriquez Horacio
Published: November 2017

Este trabajo propone una estrategia de Control por Rechazo Activo de Perturbaciones (ADRC), usando observadores extendidos de perturbación, para estabilizar una bicicleta en movimiento, sin conductor y con una velocidad de avance variable. Aunque la bicicleta tiene una dinámica inestable y no lineal alrededor de su posición vertical, que puede modelarse como un sistema Lineal de Parámetros Variantes (LPV) dependientes de la velocidad, el diseño del controlador usa un modelo simplificado de parámetros concentrados invariantes en el tiempo y una velocidad nominal constante. El esquema ADRC agrupa las discrepancias entre el modelo simplificado y la planta, junto con las perturbaciones externas en una señal aditiva unificada, que es estimada a través del observador y realimentada mediante una ley de control lineal para rechazarla. La efectividad de la estrategia es validada mediante una co-simulación entre ADAMS y MATLAB, la cual exhibe un alto desempeño y robustez sobre un modelo dinámico virtual de la bicicleta, sometida a perturbaciones externas severas y variaciones de parámetros.
Aerosol trends as a potential driver of regional climate in the central United States: evidence from observations
Authors: Cusworth Daniel H. , Mickley Loretta J. , Leibensperger Eric M. , Iacono Michael J.
Published: November 2017

Abstract. In situ surface observations show that downward surface solar radiation (SWdn) over the central and southeastern United States (US) has increased by 0.58–1.0 Wm−2 a−1 over the 2000–2014 time frame, simultaneously with reductions in US aerosol optical depth (AOD) of 3.3–5.0  ×  10−3 a−1. Establishing a link between these two trends, however, is challenging due to complex interactions between aerosols, clouds, and radiation. Here we investigate the clear-sky aerosol–radiation effects of decreasing US aerosols on SWdn and other surface variables by applying a one-dimensional radiative transfer to 2000–2014 measurements of AOD at two Surface Radiation Budget Network (SURFRAD) sites in the central and southeastern United States. Observations characterized as clear-sky may in fact include the effects of thin cirrus clouds, and we consider these effects by imposing satellite data from the Clouds and Earth's Radiant Energy System (CERES) into the radiative transfer model. The model predicts that 2000–2014 trends in aerosols may have driven clear-sky SWdn trends of +1.35 Wm−2 a−1 at Goodwin Creek, MS, and +0.93 Wm−2 a−1 at Bondville, IL. While these results are consistent in sign with observed trends, a cross-validated multivariate regression analysis shows that AOD reproduces 20–26 % of the seasonal (June–September, JJAS) variability in clear-sky direct and diffuse SWdn at Bondville, IL, but none of the JJAS variability at Goodwin Creek, MS. Using in situ soil and surface flux measurements from the Ameriflux network and Illinois Climate Network (ICN) together with assimilated meteorology from the North American Land Data Assimilation System (NLDAS), we find that sunnier summers tend to coincide with increased surface air temperature and soil moisture deficits in the central US. The 1990–2015 trends in the NLDAS SWdn over the central US are also of a similar magnitude to our modeled 2000–2014 clear-sky trends. Taken together, these results suggest that climate and regional hydrology in the central US are sensitive to the recent reductions in aerosol concentrations. Our work has implications for severely polluted regions outside the US, where improvements in air quality due to reductions in the aerosol burden could inadvertently pose an enhanced climate risk.
Integrated Impact of Digital Elevation Model and Land Cover Resolutions on Simulated Runoff by SWAT Model
Authors: Al-Khafaji Mahmoud Saleh , Al-Sweiti Fouad Hussein
Published: November 2017

Abstract. Complemental interactive effects of the Digital Elevation Model (DEM) and Land Cover (LC) resolutions on the estimated runoff by using Soil and Water Assessment Tool (SWAT), which is of critical importance for water resource management, was investigated in this paper. Also, to specify the optimal DEM and LC resolutions for maximizing accuracy of the estimated runoff for Dokan, Adhaim, and Duhok watersheds located in Iraq. Twenty daily time step based SWAT models of each watershed were implemented using five DEMs in conjunction with five LCs. Assessment of models results shows that the watershed delineation significantly affected by DEM resolution, especially in flat regions. However, there is no clearly discernible trend of this effect on the determination of watershed boundary, stream network, number of sub-basins and total area. Furthermore, the number of Hydrologic Response Units (HRUs) and the maximum altitudes are directly related to the DEM whereas the minimum altitudes have an inverse relationship with the DEM. Also, the number of HRUs increases with the increase in LC resolution until it reaches a maximum value and then starts to gradually decrease. While there is no significant trend between the accuracy of the estimated runoff and the increase in the DEM and LC resolutions. The most accurate estimated runoffs of Dokan, Adhaim and Duhok Watersheds were obtained by using DEM 90 m and LC 1000 m, DEM 250 m and LC 1000 m, and DEM 30 m and LC 30 m with Nash and Sutcliffe Efficiency of 0.59, 0.68 and 0.69 respectively.
Toward force detection of a cable-driven micromanipulator for a surgical robot based on disturbance observer
Authors: Wang Wenjie , Yu Lingtao , Yang Jing
Published: November 2017

Abstract. Force sensing plays an important role in minimally invasive surgery (MIS). Force sensing makes it possible for the surgeon to feel the tissue properties and apply an appropriate level force and avoid tissue damage. The micromanipulators are compact and to allow appropriate disinfection, it is inappropriate to integrate sensors at the end of the micromanipulator. In this study, a new asymmetric cable-driven type of micromanipulator for a surgical robot was designed, and a joint angle estimator (JAE) was designed based on the dynamical model of the single cable-driven joint. Closed-loop control of the joint angle was carried out by regarding the JAE output as the feedback signal. On this basis, an external force estimator was designed using a disturbance observer (DOB). The experimental results show an average accuracy of the joint angle estimator of about −0.150°, with excellent control precision, the largest absolute error of about 0.95°, and an average error of 0.175°. The accuracy of the force estimator was at a high level during static loading. The estimated accuracy was 94 % at external force is greater than 1 N, and the estimated accuracy was 82 % for an external force of 0.3 N. These results predict that force sensing of a cable-driven micromanipulator in this paper can used to realize the micromanipulator's force feedback of a minimally invasive surgical robot.
Adriano y el calendario imperial de juegos atléticos: propuesta sobre el tercer y cuarto año del ciclo olímpico
Authors: Gordillo Hervás Rocío
Published: November 2017

Este artículo intentará aportar una reconstrucción alternativa al tercer y cuarto año del calendario de juegos atléticos inscrito en la estela de Alejandría en la Tróade, siguiendo la línea de investigación de los editores de la estela, G. Petzl y E. Schwerteheim. El artículo se centrará en el interés del emperador Adriano por preservar los juegos Panateneos en su fecha tradicional en el tercer año del calendario a expensas de los juegos Píticos, que fueron movidos al cuarto año. Se explorará las consecuencias del traslado de los juegos Píticos en los juegos Ístmicos, quienes estaban íntimamente ligados a ellos, para intentar buscar una solución a la recurrente objeción de los investigadores sobre la inserción de los juegos Píticos en el cuarto año del ciclo olímpico.
Mito y realidad en la batalla entre los pigmeos y las grullas en el mundo griego y romano
Authors: Ovadiah Asher , Mucznik Sonia
Published: November 2017

Escritores antiguos, tales como Homero, Esopo, Hecateo de Mileto, Herodoto, Aristóteles, Filóstrato, Plinio el Viejo, Juvenal y otros se refirieron frecuentemente a la enemistad y guerra entre los pigmeos y las grullas. Es posible que este cuento popular fuese transmitido a los griegos a través de fuentes egipcias. Obras de arte visual griegas y romanas describen a los pigmeos luchando contra el ataque violento de las grullas. Este artículo examina las razones de las representaciones literarias y artísticas de esta batalla (Geranomachia) en el contexto de la migración de estas aves en el otoño desde el Caúcaso (llanuras de Escitia) hasta el África Central (Ecuatorial). Además, intentará clarificar si las fuentes literarias y las obras artísticas reflejan el mito y la realidad
Una aproximación al marco teórico de los riesgos
Authors: Sotelo Pérez María , Sotelo Pérez Ignacio
Published: November 2017

En el presente estudio se lleva a cabo un análisis pormenorizado de la importancia que tiene, en los momentos actuales, la protección del Medio Ambiente de los distintos “riesgos, peligros, impactos y desastres”. Y, es que, el medio ambiente que nos rodea ha de ser valorado, conservado y protegido mediante eficaces y eficientes medidas de preservación, de modo que se no solo sirva para obtener crecimiento meramente económico, sino que se integre en los propios modelos de desarrollo, permitiendo generar un entorno ambiental y ecológico justo, equitativo y, sobre todo, de calidad, para el conjunto de la ciudadanía.
Plan de Dinamización Turística de la Montaña de Riaño
Authors: García Díez Noelia
Published: November 2017

El presente trabajo realiza un análisis del medio físico, la situación social y económica y la perspectiva turística de una comarca del noroeste leonés, conocida como la Montaña de Riaño. De esta forma, nos acercaremos tanto a los problemas que deberán ser abordados y solucionados, como a las ventajas y atractivos que pueden suponer un incentivo turístico. El objetivo principal será el planteamiento de propuestas e iniciativas para la implantación de un Plan de Dinamización Turística (PDT) que convierta a este territorio en un núcleo de atracción sostenible y respetuoso con el entorno, preservando, asimismo, los usos y costumbres tradicionales y dotándolos de un valor turístico.
Nuevo Modelo de Desarrollo de las Comarcas Mineras de Teruel, a partir de los Planes de Ayudas al Carbón
Authors: Serrano Prades Sofía
Published: November 2017

Los sucesivos planes de reordenación de la industria de la minería del carbón iniciados a mediados de la década de los 80 no tuvieron los resultados esperados. Las ayudas en su mayoría, dirigidas desde un punto de vista puramente económico, fueron destinas a cubrir los costes de explotación, así como las prejubilaciones e indemnizaciones por despido. Así, la reactivación de las cuencas mineras no produjo alternativas económicas suficientes como para suponer una alternativa real al carbón. De este modo, en el actual Plan de Cierre 2013-2018, las cuencas mineras de Teruel se enfrentan a un futuro igual de negro que el carbón, ya que de no haber una alternativa económica el destino del territorio está condenado.