bluuebunny/crossref_metadata_2025 huggingface dataset:
Kidney Lipidomics by Mass Spectrometry Imaging: A Focus on the Glomerulus
Authors: Abbas Imane , Noun Manale , Touboul David , Sahali Dil , Brunelle Alain , Ollero Mario
Published: April 2019

Lipid disorders have been associated with glomerulopathies, a distinct type of renal pathologies, such as nephrotic syndrome. Global analyses targeting kidney lipids in this pathophysiologic context have been extensively performed, but most often regardless of the architectural and functional complexity of the kidney. The new developments in mass spectrometry imaging technologies have opened a promising field in localized lipidomic studies focused on this organ. In this article, we revisit the main works having employed the Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) technology, and the few reports on the use of TOF-Secondary Ion Mass Spectrometry (TOF-SIMS). We also present a first analysis of mouse kidney cortex sections by cluster TOF-SIMS. The latter represents a good option for high resolution lipid imaging when frozen unfixed histological samples are available. The advantages and drawbacks of this developing field are discussed.
Statistical Arbitrage with Mean-Reverting Overnight Price Gaps on High-Frequency Data of the S&P 500
Authors: Stübinger Johannes , Schneider Lucas
Published: April 2019

This paper develops a fully-fledged statistical arbitrage strategy based on a mean-reverting jump–diffusion model and applies it to high-frequency data of the S&P 500 constituents from January 1998–December 2015. In particular, the established stock selection and trading framework identifies overnight price gaps based on an advanced jump test procedure and exploits temporary market anomalies during the first minutes of a trading day. The existence of the assumed mean-reverting property is confirmed by a preliminary analysis of the S&P 500 index; this characteristic is particularly significant 120 min after market opening. In the empirical back-testing study, the strategy delivers statistically- and economically-significant returns of 51.47 percent p.a.and an annualized Sharpe ratio of 2.38 after transaction costs. We benchmarked our trading algorithm against existing quantitative strategies from the same research area and found its performance superior in a multitude of risk-return characteristics. Finally, a deep dive analysis shows that our results are consistently profitable and robust against drawdowns, even in recent years.
Effects of Extrusion on Mechanical and Corrosion Resistance Properties of Biomedical Mg-Zn-Nd-xCa Alloys
Authors: Lou Gui , Xu Shumin , Teng Xinying , Ye Zhijian , Jia Peng , Wu Hao , Leng Jinfeng , Zuo Min
Published: April 2019

Magnesium alloys act as ideal biomedical materials with good biocompatibility. In this paper, the extruded biomedical Mg-6Zn-0.5Nd-0.5/0.8Ca alloys were prepared and their microstructure, mechanical properties and corrosion properties were investigated. The results showed that the surfaces of Mg-6Zn-0.5Nd-0.5/0.8Ca alloys extruded at medium temperature were smooth and compact without cracks. The tensile strength and elongation of Mg-6Zn-0.5Nd-0.5/0.8Ca alloys were 222.5 MPa and 20.2%, and 287.2 MPa and 18.4%, respectively. A large number of dislocations were generated in the grains and on grain boundaries after the extrusion. The alloy was immersed in simulating body fluid (SBF) for the weightlessness corrosion, and the corrosion products were analyzed by FTIR, SEM equipped with EDS. It was found that the corrosion rate of Mg-6Zn-0.5Nd-0.5Ca and Mg-6Zn-0.5Nd-0.8Ca alloy were 0.82 and 2.98 mm/a, respectively. Furthermore, the compact layer was formed on the surface of the alloy, which can effectively hinder the permeation of Cl− and significantly improve the corrosion resistance of magnesium alloys.
Determination of Forming Limits in Sheet Metal Forming Using Deep Learning
Authors: Jaremenko Christian , Ravikumar Nishant , Affronti Emanuela , Merklein Marion , Maier Andreas
Published: April 2019

The forming limit curve (FLC) is used to model the onset of sheet metal instability during forming processes e.g., in the area of finite element analysis, and is usually determined by evaluation of strain distributions, derived with optical measurement systems during Nakajima tests. Current methods comprise of the standardized DIN EN ISO 12004-2 or time-dependent approaches that heuristically limit the evaluation area to a fraction of the available information and show weaknesses in the context of brittle materials without a pronounced necking phase. To address these limitations, supervised and unsupervised pattern recognition methods were introduced recently. However, these approaches are still dependent on prior knowledge, time, and localization information. This study overcomes these limitations by adopting a Siamese convolutional neural network (CNN), as a feature extractor. Suitable features are automatically learned using the extreme cases of the homogeneous and inhomogeneous forming phase in a supervised setup. Using robust Student’s t mixture models, the learned features are clustered into three distributions in an unsupervised manner that cover the complete forming process. Due to the location and time independency of the method, the knowledge learned from formed specimen up until fracture can be transferred on to other forming processes that were prematurely stopped and assessed using metallographic examinations, enabling probabilistic cluster membership assignments for each frame of the forming sequence. The generalization of the method to unseen materials is evaluated in multiple experiments, and additionally tested on an aluminum alloy AA5182, which is characterized by Portevin-LE Chatlier effects.
Effect of Ti on Microstructure and Properties of Tungsten Heavy Alloy Joint Brazed by CuAgTi Filler Metal
Authors: Lu Yuzhen , Qiu Xiaoming , Ruan Ye , Luo Cui , Xing Fei
Published: April 2019

In this paper, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffractometer (XRD) were used to comprehensively analyze the microstructure and brazing performance of a CuAgTi filler metal with braze tungsten heavy alloys. The association of microstructure, wettability and shear strength of brazing joints was also investigated. With the addition of Ti, the Ti3Cu4 phase appeared in the microstructure of filler metal. Ti is active element that promotes the reaction of filler with tungsten. Therefore, the Ti element is enriched around tungsten and forms a Ti2Cu layer at the interface, leaving a Cu-rich/Ti-poor area on the side. Remaining Ti and Cu elements form the acicular Ti3Cu4 structure at the center of the brazing zone. The wettability of filler metal is improved, and the spreading area is increased from 120.3 mm2 to 320.9 mm2 with the addition of 10 wt.% Ti. The shear strength of joint reaches the highest level at a Ti content of 2.5 wt.%, the highest shear strength is 245.6 MPa at room temperature and 142.2 MPa at 400 °C.
Analysis of the Effect of Processing Conditions on Physical Properties of Thermally Set Cellulose Hydrogels
Authors: Huber Tim , Feast Sean , Dimartino Simone , Cen Wanwen , Fee Conan
Published: April 2019

Cellulose-based hydrogels were prepared by dissolving cellulose in aqueous sodium hydroxide (NaOH)/urea solutions and casting it into complex shapes by the use of sacrificial templates followed by thermal gelation of the solution. Both the gelling temperatures used (40–80 °C), as well as the method of heating by either induction in the form of a water bath and hot press or radiation by microwaves could be shown to have a significant effect on the compressive strength and modulus of the prepared hydrogels. Lower gelling temperatures and shorter heating times were found to result in stronger and stiffer gels. Both the effect of physical cross-linking via the introduction of additional non-dissolving cellulosic material, as well as chemical cross-linking by the introduction of epichlorohydrin (ECH), and a combination of both applied during the gelation process could be shown to affect both the mechanical properties and microstructure of the hydrogels. The added cellulose acts as a physical-cross-linking agent strengthening the hydrogen-bond network as well as a reinforcing phase improving the mechanical properties. However, chemical cross-linking of an unreinforced gel leads to unfavourable bonding and cellulose network formation, resulting in drastically increased pore sizes and reduced mechanical properties. In both cases, chemical cross-linking leads to larger internal pores.
Investigation of the Effect of Induction Heating on Asphalt Binder Aging in Steel Fibers Modified Asphalt Concrete
Authors: Li Hechuan , Yu Jianying , Wu Shaopeng , Liu Quantao , Li Yuanyuan , Wu Yaqi , Xu Haiqin
Published: April 2019

Induction heating is a valuable technology to repair asphalt concrete damage inside. However, in the process of induction heating, induced particles will release a large amount of heat to act on asphalt binder in a short time. The purpose of this paper was to study the effect of induction heating on asphalt binder aging in steel fibers modified asphalt concrete. The experiments were divided into two parts: induction heating of Dramix steel fibers coated with asphalt binder (DA) and steel wool fibers modified asphalt concrete. After induction heating, the asphalt binders in the samples were extracted for testing aging indices with Fourier Transform Infrared (FTIR), Dynamic Shear Rheometer (DSR), and Four-Components Analysis (FCA) tests. The aging of asphalt binder was analyzed identifying the change of chemical structure, the diversification of rheological properties, and the difference of component. The experiments showed that the binder inside asphalt concrete began aging during induction heating due to thermal oxygen reaction and volatilization of light components. However, there was no peak value of the carbonyl index after induction heating of ten cycles, and the carbonyl index of DA was equivalent to that of binder in asphalt concrete after three induction heating cycles, which indicated the relatively closed environment inside asphalt concrete can inhibit the occurrence of the aging reaction.
Time Dependent Structure and Property Evolution in Fibres during Continuous Carbon Fibre Manufacturing
Authors: Nunna Srinivas , Maghe Maxime , Rana Rohit , Varley Russell J. , Knorr Daniel B. , Sands James M. , Creighton Claudia , Henderson Luke C. , Naebe Minoo
Published: April 2019

Here we report on how residence time influences the evolution of the structure and properties through each stage of the carbon fibre manufacturing process. The chemical structural transformations and density variations in stabilized fibres were monitored by Fourier Transform Infrared Spectroscopy and density column studies. The microstructural evolution and property variation in subsequent carbon fibres were studied by X-ray diffraction and monofilament tensile testing methods, which indicated that the fibres thermally stabilized at longer residence times showed higher degrees of structural conversion and attained higher densities. Overall, the density of stabilized fibres was maintained in the optimal range of 1.33 to 1.37 g/cm3. Interestingly, carbon fibres manufactured from higher density stabilized fibres possessed lower apparent crystallite size (1.599 nm). Moreover, the tensile strength of carbon fibres obtained from stabilized fibres at the high end of the observed range (density: 1.37 g/cm3) was at least 20% higher than the carbon fibres manufactured from low density (1.33 g/cm3) stabilized fibres. Conversely, the tensile modulus of carbon fibres produced from low density stabilized fibres was at least 17 GPa higher than those from high density stabilized fibres. Finally, it was shown that there is potential to customize the required properties of resultant carbon fibres suiting specific applications via careful control of residence time during the stabilization stage.
Effect of Austenitization Conditions on the Transformation Behavior of Low Carbon Steel Containing Ti–Ca Oxide Particles
Authors: Wang Chao , Wang Xin , Kang Jian , Yuan Guo , Wang Guodong
Published: April 2019

Inclusion-induced acicular ferrite (AF) nucleation has been used for microstructure refinement in steel. Austenitization conditions have a significant influence on AF nucleation ability. In this paper, the effects of austenitization temperature and holding time on the transformation behaviors of low carbon steel containing Ti–Ca oxide particles were studied. A thermal treatment experiment, high temperature in situ observation, and calculation of Mn diffusion were carried out. The results indicate that small austenite grain size under low austenitizing temperature promoted grain boundary reaction products. With an increase in austenitizing temperature, the nucleation sites transferred to intragranular particles and AF transformation was improved. The inclusion particles in the Ti–Ca deoxidized steel were featured by an oxide core rich in Ti and a lesser amount of Ca and with MnS precipitation on the local surface, which showed a strong ability to promote AF nucleation. At a low austenitizing temperature, Mn diffusion was limited and the development of Mn-depleted zones (MDZs) around inclusions was not sufficient. The higher diffusion capacity of Mn at a high austenitizing temperature promoted the formation of MDZs to a larger degree and increased the AF nucleation ability. Boron segregation at large-sized austenite grain boundaries played an important role in AF transformation. Austenite grain size, Mn-depleted zone development, and boron segregation at grain boundaries were the decisive factors influencing the transformation behaviors under different austenitization conditions for the test steel.
Effect of Arc Pressure on the Digging Process in Variable Polarity Plasma Arc Welding of A5052P Aluminum Alloy
Authors: Xu Bin , Tashiro Shinichi , Jiang Fan , Chen Shujun , Tanaka Manabu
Published: April 2019

The keyhole digging process associated with variable polarity plasma arc (VPPA) welding remains unclear, resulting in poor control of welding stability. The VPPA pressure directly determines the dynamics of the keyhole and weld pool in the digging process. Here, through a high speed camera, high frequency pulsed diode laser light source and X-ray transmission imaging system, we reveal the potential physical phenomenon of a keyhole weld pool. The keyhole depth changes periodically corresponding to the polarity conversion period if the current is same in the electrode negative (EN) phase and electrode positive (EP) phase. There exist three distinct regimes of keyhole and weld pool behavior in the whole digging process, due to the arc pressure attenuation and energy accumulation effect. The pressure in the EP phase is smaller than that of the EN phase, causing the fluctuation of the weld pool free surface. Based on the influence mechanism of energy and momentum transaction, the arc pressure output is balanced by separately adjusting the current in each polarity. Finally, the keyhole fluctuation during the digging process is successfully reduced and welding stability is well controlled.
The Effect of Elevated Curing Temperatures on High Ye’elimite Calcium Sulfoaluminate Cement Mortars
Authors: Jeong Yeonung , Hargis Craig W. , Kang Hyunuk , Chun Sung-Chul , Moon Juhyuk
Published: April 2019

This study investigated the material properties and hydration characteristics of calcium sulfoaluminate cement (CSA) based mortars cured under 3 different initial curing temperatures. Two CSA cements with different M-values were selected. Obtained experimental results of mechanical properties, dimensional stability, and heat release were explained by hydration characteristics from X-ray diffraction, thermal gravimetric analysis, porosimetry, and thermodynamic modeling. Decomposition of ettringite decreased compressive strength but re-formation of ettringite after additional curing at 30 °C helped to recover the strength in CSA cement with a high amount of calcium sulfate. CSA cement with a low amount of calcium sulfate which was designed to predominantly have monosulfate as the main hydration product, showed increased 1-day strength after higher temperature curing but this occurred was at the expense of decreased 28-day strength.
Remodeling of Intrahepatic Ducts in a Model of Caroli Syndrome: Is Scar Carcinoma a Consequence of Laplace’s Law?
Authors: Chavre Bharvi M. , Jiang Kai , St. Surin Luce G. , Bissoondial Terrence , Zhou Ping , Li Jingsong , Gadhiya Satishkumar V. , Goldberg Itzhak D. , Narayan Prakash
Published: April 2019

Caroli syndrome, characterized by saccular dilatation of intrahepatic ducts and congenital hepatic fibrosis, is without therapy in part due to its ultra-rare prevalence and the apparent lack of availability of a suitable experimental model. While the PCK rat has long been used as a model of fibropolycystic kidney disease, hepatobiliary biophysics in this animal model is incompletely characterized. Compared to age-matched, wild-type controls, the PCK rat demonstrated severe hepatomegaly and large saccular dilated intrahepatic ducts. Nevertheless, hepatic density was greater in the PCK rat, likely due to severe duct wall sclerosis accompanied by scarring across the hepatic parenchyma. Extracellular matrix accumulation appeared proportional to duct cross-sectional area and liver volume and appeared compensatory in nature. The PCK rat livers exhibited both cholangiocarcinoma and hepatocellular carcinoma coincident with areas of increased extracellular matrix deposition. Together, these data suggest that the PCK rat model mimics at least in part the spectrum of hepatobiliary pathology observed in Caroli syndrome and highlights the attendant risk associated with this disease.
Corrosion Behavior of Fe-Ni-Al Alloy Inert Anode in Cryolite Melts
Authors: Guan Pingping , Liu Aimin , Shi Zhongning , Hu Xianwei , Wang Zhaowen
Published: April 2019

Fe-Ni-based alloys are promising materials of inert anodes for use in aluminum electrolysis and adding Al can further improve the corrosion resistance. Fe-Ni-Al alloys with 1.4–8.6 wt.% Al were prepared by vacuum melting, and their corrosion as anodes during the production of pure Al (98.14–99.68%) by electrolysis was studied in a melt of NaF-AlF3-NaCl-CaF2-Al2O3 at 850 °C. The corrosion layer on the anode contains fluorine salt that corrodes the oxide film, and the inner layer is Ni-enriched while the outer layer is enriched with Fe and O due to the preferential oxidation of Fe. The electrolytically deposited oxide films on Fe-Ni-Al alloys with different compositions contains Fe2O3, Fe3O4, NiO, Al2O3, FeAl2O4, NiFe2O4, and other protective oxides, making the alloys very corrosion-resistant. The linear voltammetric curves can be divided into three parts: active dissolution, passivation transition, and over-passivation zones. The alloy with 3.9 wt.% Al (57.9Fe-38.2Ni-3.9Al) has a relatively negative passivation potential, and therefore, is easier to become passivated. According to the Tafel curve, this alloy shows a relatively positive corrosion potential as anode (1.20 V vs. Al/AlF3), and thus can form a protective film.
Comparative Transcriptome Analysis of Ampelopsis megalophylla for Identifying Genes Involved in Flavonoid Biosynthesis and Accumulation during Different Seasons
Authors: Yang Min , Zhou Peina , Gui Chun , Da Guozheng , Gong Ling , Zhang Xiuqiao
Published: April 2019

Ampelopsis megalophylla is an important species used in Chinese folk medicine. Flavonoids, the most important active components of plants, greatly determine the quality of A. megalophylla. However, biosynthesis of flavonoids at the molecular and genetic levels in A. megalophylla is not well understood. In this study, we performed chemical analysis and transcriptome analysis of A. megalophylla in different seasons (i.e., May, August, and October). Accumulation of flavonoids was higher in May than in the other two months. Genes involved in the flavonoid biosynthesis pathway, such as chalcone synthase, anthocyanidin synthase, flavanone 3-hydroxylase, flavonoid-3′,5′-hydroxylase, caffeoyl-CoA O-methyltransferase, dihydroflavonol 4-reductase, 4-coumarate-CoA ligase, phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, flavonoid 3′-monooxygenase, shikimate O-hydroxycinnamoyltransferase, and leucoanthocyanidin reductase, were identified based on transcriptome data. Fifty ATP binding cassette (ABC) transporter, nine SNARE, forty-nine GST, and eighty-four glycosyltransferases unigenes related to flavonoid transport and biomodification were also found. Moreover, seventy-eight cytochrome P450s and multiple transcription factors (five MYB, two bHLH, and three WD40 family genes) may be associated with the regulation of the flavonoid biosynthesis process. These results provide insights into the molecular processes of flavonoid biosynthesis in A. megalophylla and offer a significant resource for the application of genetic engineering in developing varieties with improved quality.
“I Knew Him, Horatio”: Shakespeare’s Beliefs, Early Textual Editing, and Nineteenth-Century Phrenology
Authors: Hampton Bryan Adams
Published: April 2019

As Hamlet gazes into Yorick’s skull, he reassembles the quirks of the jester’s personhood and also imagines a self that he used to be, in relation to Yorick. Partially through the lens of Hamlet, characterized by A.C. Bradley as Shakespeare’s most “religious” play, this essay interrogates how several eighteenth-century textual editors, and some nineteenth-century scholars and popular admirers, imagine and construct Shakespeare’s beliefs: the first, through their efforts to reassemble the textual “bones” of Shakespeare’s works; and the second, through the rising pseudoscience of phrenology, operating in the background in the national debate to exhume and examine Shakespeare’s skull.
Monastic Meat: The Question of Meat Eating and Vegetarianism in Tibetan Buddhist Monastic Guidelines (bca’ yig)
Authors: Barstow Geoffrey
Published: April 2019

The practice of vegetarianism has long been connected with monasticism in Tibet, despite explicit statements in the vinaya that monks and nuns are allowed to eat meat. This paper examines one particular aspect of this connection: the rules governing meat eating found in monastic guidelines. Texts of this genre reveal a variety of approaches to the question of meat eating, from avoiding the issue entirely (the most common) to banning meat outright (the least). In this paper I argue that, when viewed collectively, those monastic guidelines that discuss meat do so in a measured way that makes clear that while meat is not fully condoned, individual monks or nuns can choose how strictly they will adhere to this ideal. Meat was, thus, generally permitted, but within a context in which it was still viewed in a negative light.
Bioethics and Jainism: From Ahiṃsā to an Applied Ethics of Carefulness
Authors: Donaldson Brianne
Published: April 2019

Although Jainism has been largely absent from discourses in bioethics and religion, its rich account of life, nonviolence, and contextual ethical response has much to offer the discussion within and beyond the Jain community. In this essay, I explore three possible reasons for this discursive absence, followed by an analysis of medical treatment in the Jain tradition—from rare accommodations in canonical texts to increasing acceptance in the post-canonical period, up to the present. I argue that the nonviolent restraint required by the ideal of ahiṃsā is accompanied by applied tools of carefulness (apramatta) that enable the evolution of medicine. These applied tools are derived from the earliest canonical strata and offer a distinct contribution to current bioethical discourses, demanding a more robust account of: (1) pervasive life forms; (2) desires and aversions that motivate behavior; (3) direct and indirect modes of harm; and (4) efforts to reduce harm in one’s given context. I conclude by examining these tools of carefulness briefly in light of contemporary Jain attitudes toward reproductive ethics, such as abortion and in vitro fertilization.
Reconstruction of 3D Object Shape Using Hybrid Modular Neural Network Architecture Trained on 3D Models from ShapeNetCore Dataset
Authors: Kulikajevas Audrius , Maskeliūnas Rytis , Damaševičius Robertas , Misra Sanjay
Published: April 2019

Depth-based reconstruction of three-dimensional (3D) shape of objects is one of core problems in computer vision with a lot of commercial applications. However, the 3D scanning for point cloud-based video streaming is expensive and is generally unattainable to an average user due to required setup of multiple depth sensors. We propose a novel hybrid modular artificial neural network (ANN) architecture, which can reconstruct smooth polygonal meshes from a single depth frame, using a priori knowledge. The architecture of neural network consists of separate nodes for recognition of object type and reconstruction thus allowing for easy retraining and extension for new object types. We performed recognition of nine real-world objects using the neural network trained on the ShapeNetCore model dataset. The results evaluated quantitatively using the Intersection-over-Union (IoU), Completeness, Correctness and Quality metrics, and qualitative evaluation by visual inspection demonstrate the robustness of the proposed architecture with respect to different viewing angles and illumination conditions.
Ag@Au Core–Shell Porous Nanocages with Outstanding SERS Activity for Highly Sensitive SERS Immunoassay
Authors: Huang Yaqi , Lin Dajie , Li Mengting , Yin Dewu , Wang Shun , Wang Jichang
Published: April 2019

A highly sensitive immunoassay of biomarkers has been achieved using 4-mercaptobenzoic acid-labeled Ag@Au core–shell porous nanocage tags and α-fetoprotein immuno-sensing chips. The Ag@Au porous nanocages were uniquely synthesized by using an Ag core as a self-sacrificial template and reducing agent, where the slow reaction process led to the formation of a porous Au layer. The size of the remaining Ag core and surface roughness of the Au shell were controlled by adjusting the chloroauric acid concentration. The porous cage exhibited excellent surface-enhanced Raman spectroscopy (SERS) activity, presumably due to a synergetic interaction between newly generated hot spots in the rough Au shell and the retained SERS activity of the Ag core. Using α-fetoprotein as a model analyte for immunoassay, the SERS signal had a wide linear range of 0.20 ng mL−1 to 500.0 ng mL−1 with a detection limit of 0.12 ng mL−1. Without the need of further signal amplification, the as-prepared Ag@Au bimetallic nanocages can be directly used for highly sensitive SERS assays of other biomarkers in biomedical research, diagnostics, etc.
Flexible Three-Dimensional Reconstruction via Structured-Light-Based Visual Positioning and Global Optimization
Authors: Yin Lei , Wang Xiangjun , Ni Yubo
Published: April 2019

Three-dimensional (3D) reconstruction using line structured light vision system commonly cooperates with motion restraint devices, such as parallel guide rail push-broom devices. In this study, we propose a visual positioning method to eliminate the motion constraint. An extended orthogonal iteration algorithm for visual positioning is proposed to obtain the precise position of the line structured light binocular camera system during movement. The algorithm uses the information acquired by the binocular camera, and produces a better positioning accuracy than the traditional vision localization algorithm. Furthermore, a global optimization method is proposed to calculate the poses of the camera relative to the world coordinate system at each shooting position. This algorithm effectively reduces the error accumulation and pose drift during visual positioning, and 3D information of the surface can be measured via the proposed free-moving line structured light vision system. The simulation and physical experiments performed herein validate the proposed method and demonstrate the significant improvement in the reconstruction accuracy: when the test distance is 1.5 m, the root mean square error of the point cloud is within 0.5 mm.
Advances in Methylmercury Toxicology and Risk Assessment
Authors: Chan Hing Man
Published: April 2019

Mercury (Hg) is a global pollutant that affects the health of both humans and ecosystems [...]
Síndrome neuroléptico maligno. Presentación de un caso y revisión de la literatura
Authors: Colón Núñez Solangel , López Santacruz Yenis Angélica , Brito Hernández Alberto
Published: April 2019

El Síndrome Neuroléptico Maligno (SNM), es una peculiar y peligrosa complicación del tratamiento con fármacos antipsicóticos, que se caracteriza por fiebre, rigidez muscular severa y cambios en el estado autonómico y mental. Se realizó una revisión de los aspectos epidemiológicos, fisiopa- tológicos, diagnósticos y enfoques terapéuticos siguiendo una investigación cualitativa descriptiva con  triangulación  de información,  resultado  del  análisis  de  la  historia  clínica,  del  seguimiento  y evolución del caso en la terapia intensiva y apoyada en la revisión de la literatura científica, sobre esta patología. Se presenta el caso clínico de un paciente con el SNM, después de la medicación con antipsicóticos, del tipo haloperidol, asociado a la administración de metoclopramida y que por sus complicaciones, presentó arritmias cardiacas, trastornos del medio interno y trombosis venosa profunda del miembro inferior izquierdo, lo que necesitó el ingreso en la unidad de cuidados inten- sivos. Como conclusión, se destaca la importancia de mantener la vigilancia teniendo en cuenta un pensamiento clínico sobre los síntomas iniciales o de alerta de esta entidad, lo que permitirá realizar un diagnóstico precoz e iniciar un tratamiento oportuno y adecuado, logrando así reducir la morbimortalidad asociada.

Palabras clave: Fármacos antipsicóticos, complicaciones asociadas, síndrome, morbimortalidad.

Abstract:

The Neuroleptic Malignant Syndrome (NMS) is a peculiar and dangerous complication of treatment with antipsychotic drugs, which is characterized by fever, severe muscle stiffness and autonomic and mental status changes. We conducted a review of the epidemiological aspects, physiopatholog- ical, diagnosis and therapeutic approaches following a descriptive qualitative research with triangu- lation of information, results of the analysis of the clinical history, monitoring and evolution of case in intensive therapy and supported in the review of the scientific literature about this pathology, the clinical case of a patient who presented the NMS, after medication with antipsychotics, haloperidol type, associated with the administration of metoclopramide and presented  complications like cardi- ac arrhythmias, disorders of the internal environment and deep venous thrombosis of the left lower limb, which needed admission to the intensive care unit. As conclusion we highlight the importance of maintaining surveillance taking into account clinical thinking about early symptoms or warning of this entity, which will allow early diagnosis and initiate treatment timely and appropriate, and thus reducing the associated mortality and morbidity.

Key words: Drugs antipsychotic, associated complications, syndrome, morbidity and mortality.
Comportamiento del endotelio corneal con la técnica de Mini-Nuc, una experiencia con 50 pacientes
Authors: Martínez Carballo Martha
Published: April 2019

La cirugía de catarata es causa frecuente de edema corneal; este puede expresarse clínicamente en el postoperatorio inmediato o hacerlo muy tardíamente como consecuencia de la pérdida progresiva de células endoteliales que origina por sí mismo este procedimiento. Por este motivo, se realizó un estudio descriptivo, prospectivo, de corte longitudinal, con el objetivo de determinar las alteraciones del endotelio corneal en pacientes operados de catarata mediante la Técnica de Mini-Nuc, en el Hospital Calixto García. La investigación incluyó 50 pacientes que cumplieron con los criterios de inclusión y se realizó en el período comprendido entre septiembre de 2009 y septiembre de 2010. Algunos de los resultados más sobresalientes fueron: se evidenció modificación significativa de la densidad celular, el coeficiente de variabilidad y el índice de hexagonalidad luego de la realización del proceder quirúrgico, no sucediendo lo mismo con la paquimetría óptica. El polimegatismo y pleomorfismo aumentaron en el postoperatorio, al igual que la presencia de espacios acelulares. A pesar de comprobar la presencia en el postquirúrgico de alteraciones estructurales en el endotelio corneal, estas no comprometieron de manera irreversible su funcionamiento

Palabras clave: Endotelio corneal, postquirúrgicos, densidad celular, hexagonalidad, coeficiente de variabilidad, oftalmología.

 Abstract

Cataract surgery is a common cause of corneal edema; this can express itself clinically in the immediate postoperative period or late as a result of the progressive loss of endothelial cells that originates by itself this proceeding. In order to determine changes in the corneal endothelium in 50 patients with diagnosis of cataract operated by Mini Nuc technique, a descriptive and prospective study was conducted at the Hospital General Calixto García University, which met the criteria of inclusion, from September 2009 to September 2010. The outstanding results, showed the significant change cell density, coefficient of variability and the hexagonal index, while with the optical pachymetry was not the same. The polimegatism and pleomorphism and acellular spaces increased in the postoperative period. Despite presence of structural alterations in corneal endothelium during post-operatory period, they did not affect irreversibly the endothelium working.

Key words: Corneal endothelium, post-surgery, cell density, coefficient of variability and rate of hexagonal forms.
Asociaciones entre alimentos, flora intestinal y sistema nervioso central
Authors: Caballero Torres Angel Eladio , Fernández Vélez Yumy Estela
Published: April 2019

Existe un incremento del interés sobre posibles efectos de la alimentación en el funcionamiento del sistema nervioso central, aunque la importancia de esa influencia parece requerir mayores respaldos científicos. Estos señalamientos son motivos para   valorar, sobre la base de los aportes de otros autores, el posible significado de la relación de alimentos, flora intestinal y sistema nervioso. Para cumplir este objetivo fue necesario una búsqueda de informaciones científicas en la US National Library of Medicine sobre este tema, una selección de publicaciones relevantes y análisis de los datos encontrados. Según esas publicaciones, la protección de la inocuidad de los alimentos, probióticos y algunas sustancias químicas de la dieta tienen relación con la composición y funcionamiento de la flora intestinal que puede afectar el eje intestino cerebro y causar alteraciones en el funcionamiento del sistema nervioso central. Se acepta que son insuficientes las explicaciones sobre relaciones específicas entre componentes de la dieta y efectos en el sistema nervioso central de los consumidores de alimentos, incluyendo los posibles mecanismos de esas relaciones.

 

Palabras clave: alimentos, eje intestino cerebro, sistema nervioso central, microbiota intestinal.

 

Abstract

 

There is an increased interest in possible effects of food on the central nervous system functioning, although the importance of this influence seems to require more scientific support. These indications are reasons to value, based on the contributions of other authors, the possible meaning of the relationship of food with the intestinal flora and the nervous system. To accomplish this goal, a search of scientific information was necessary for the US National Library of Medicine on this topic, a selection of relevant publications and analysis of the data found. According to those publications, food safety, probiotics and some dietary chemicals has a relationship with to the composition and functioning of the intestinal microbiome that can affect the brain intestinal axis and cause alterations in the functioning of the central nervous system. It’s accepted that explanations about specific relationships between diet components and effects on the central nervous system of food consumers, including the possible mechanisms of these relationships, are insufficient.

 

Key words: food, intestine brain axis, central nervous system, nutrition, intestinal microbiota.
El buen humor para el buen vivir de la educación
Authors: Zambrano Cedeño Edison Rubén , Barcia Briones Marcelo Fabián
Published: April 2019

Cuando  se  habla  de  buen  humor,  muchos  poseen  la  acepción  de  que son  la  risa  y  el  chiste  sus  elementos  principales  dentro  de  su desarrollo,  sin  embargo,  el  buen  humor  implica  un  estado  más amplio que la simple jocosidad, implica el entorno mismo del ser humano para desenvolverse dentro de la sociedad; ya en educación se puede decir que es el entorno y el ambiente de aprendizaje que el  docente propicia  para  poder  desarrollar  las  capacidades  de cada  uno  de  sus  estudiantes.  Este  trabajo  se  realizó  en  dos partes: la primera en la que consta la literatura del buen humor dentro  del  contexto  mundial, que  por  ser  un  campo  no  muy explorado se torna un tanto complicado en cuanto a sus líneas de trabajo  especialmente  en  el  ámbito  educativo  siendo  un  elemento psicopedagógico  dentro  del  quehacer educacional  y  como  una herramienta  esencial  para  lograr  los  resultados  deseados;  la segunda  parte  contiene  experiencias  vividas  y  resultados  de estudios  ejecutados  con  estudiantes  universitarios.  Se concluye con  la  teoría  de  que  el  aplicar  el  buen  humor  en  el  aula  de clases  es  una  ayuda  efectiva  para  lograr  aprendizajes significativos en el estudiante.
Diseño de guiones metodológicos de recorridos guiados
Authors: Pino Urías Naima , Pino Torrens Ricardo , Urías Arboláez Graciela
Published: April 2019

En  Cuba  la  actividad  turística  ha  ido  ganando  auge  durante  las últimas décadas. Entre los atractivos ofertados se encuentran los productos  de  recorrido,  que  en  la  mayoría  de  las  ocasiones requieren  de  un guía  para  su  conducción.  El  guía  de  turismo  es uno de los principales comunicadores de un destino; su trabajo es dinámico y requiere de mucho tiempo y organización. Los productos que  conduce  el  guía  están diseñados  con  anterioridad,  pero  el guion  del  recorrido  que  va  a  llevar  a  cabo  tiene  que  ser  creado por  él,  lo  cual  ocurre  no  pocas  veces,  de  forma  espontánea  y generalmente  poco  organizada;  esto constituye  un  serio  problema para  desarrollar  la  actividad.  En  la  literatura  consultada  se detectan  carencias  de  metodologías  o  procedimientos  para  el esbozo  de  los  guiones  para  la  conducción  de recorridos  guiados, así  como  poca  orientación  con  respecto  a  la  aplicación  de  las técnicas  de  interpretación  del  patrimonio  natural  y  cultural, causas  por  las  cuales  el  trabajo  del  guía  se  presenta  como un proceso  empírico  y  espontáneo,  es  por  ello  que  la  presente investigación  propone  un  procedimiento  para  el  diseño  de recorridos  turísticos  guiados;  en  ella  se  explican  las  técnicas de guiaje y de interpretación  del patrimonio. Este procedimiento es  aplicable  a  todas  las  modalidades  turísticas  y  a  todos aquellos productos que requieran de la actuación de un guía para que  su  trabajo  sea  organizado, orientado  en  sus  objetivos  y estrategias,  y  logre  comunicar  una  imagen  de  destino  adecuada  a los intereses del mercado y del país.
Propuesta de un modelo para el aprendizaje de hábitos posturales en la escuela
Authors: Ramiro Monroy Edgar
Published: April 2019

Entre  los  factores  ambientales  que  influyen  en  las  alteraciones osteomusculares  del niño son las posturas inadecuadas durante el sueño,  el  tiempo  de  juego  y  como  se  sienta1.  Entre  los  factores se encuentran:  posturas inadecuadas y mantenidas por periodos de tiempo;  peso  y  colocación  incorrecta  de  la  mochila;  gestos incorrectos y estilos de vida, en relación a la actividad física y al sedentarismo. El dolor lumbar en estudiantes es un problema de  salud  pública  en  aumento  y  su  presencia  incrementa  el  riesgo de  sufrir  dolor  lumbar  en  el  futuro.  Varios  estudios referenciados  demuestran  que  el  dolor  lumbar puede  ocasionar discapacidad y limitar las actividades diarias entre el 9,7% y el 40%  de  los  adolescentes.  La  mayoría  de  las  alteraciones  de columna  vertebral  se  pueden  prevenir  mediante  una  educación postural en la edad escolar, si el centro educativo dispone de un modelo  de  concienciación  postural  precoz  para  adoptar  posturas neutrales,  en  el  aula  y  fuera  de  ellas,  que  podrían  convertirse en  hábitos que prevenga  enfermedades  musculo  esqueléticas  en  la adultez.  El  objeto  es  proponer  un  modelo  de  aprendizaje  de hábitos  posturales  preventivos,  para  centros  educativos  de primaria  y  secundaria  y siguiendo  el  concepto  de  Rapport  au savoir, basado en el sentido que le da al aprender y al saber de las  posturas  ergonómicas,  al  compromiso  consigo  mismo  en aplicarlas, con los otros y el mundo.
Atención de los docentes universitarios a estudiantes con discapacidad:caso Universidad Politécnica Salesiana
Authors: Gallego Condoy Miriam , Gallegos Navas Miriam
Published: April 2019

Esta investigación analiza los apoyos académicos que brindan los docentes de la Universidad Politécnica Salesiana a los estudiantes con discapacidad para garantizar su aprendizaje y participación, y muestra las dificultades que encuentran en su práctica docente. Participaron en el estudio una muestra de 48 docentes de las Sedes Quito, Guayaquil y Cuenca que durante el curso 2014-2015 tuvieron estudiantes con discapacidad en sus aulas. Los docentes respondieron a un cuestionario estructurado en torno a cuatro dimensiones básicas: capacitación recibida, práctica inclusiva en el aula, percepción del nivel  de  concienciación  y  necesidades  de  capacitación.  Dentro  de  los  hallazgos  importantes  en  la  investigación  se  constata  el  hecho  de  que  el profesorado  universitario  no  está  preparado  para  dar  una  respuesta  educativa  ajustada  a  las  necesidades  de  aprendizaje  de  los  estudiantes  con discapacidad, dejando  en evidencia,  la demanda de una  formación en  el  uso de  estrategias y  recursos.  El  trabajo  de atención a  los  estudiantes con discapacidad que realizan los docentes es voluntarista.
Estrategias para la comercialización de los servicios académicos internacionales de la Universidad de Holguín
Authors: Font Osorio Yaneidy , López Báster Liliana , Riverón Hernández Matilde , Velázquez Zaldivar Reynaldo
Published: April 2019

La Universidad de Holguín desde hace varios años presenta insuficientes niveles de ingresos por los servicios académicos internacionales pregrado y posgrado internacional. Situación contradictoria, ya que estos servicios constituyen las fuentes fundamentales de ingresos netos que se obtienen en el marco del autofinanciamiento de las universidades cubanas; sin obviar el hecho de que la razón social de las mismas es formar profesionales. Es por ello que la presente investigación tiene como objetivo el diseño y aplicación de un procedimiento para la elaboración de estrategias de gestión comercial para los servicios académicos internacionales en la Universidad de Holguín, a fin de resolver las insuficiencias existentes. Se parte del estudio de aspectos de carácter teórico práctico conceptual relacionados con los procesos de comercialización y de planeación estratégica, como instrumentos de trabajo para contribuir al perfeccionamiento del sistema de comercialización. Esto permitirá lograr una mayor precisión de las acciones de colaboración internacional que deberán emprenderse para garantizar el sostenible desarrollo que demanda la Universidad de Holguín. Los análisis desarrollados constituyen el fundamento investigativo y los resultados obtenidos demuestran la factibilidad, pertinencia y significación práctica de la investigación.
El trabajo metodológico en el año académico: necesidad para elevar la calidad de la clase en la Educación Superior
Authors: Miqueli Rodríguez Bertha , Polo Robaina Melba
Published: April 2019

El artículo, (de revisión bibliográfica), recoge uno de los resultados del proyecto de investigación de la Universidad de Artemisa, Cuba. Su objetivo es fundamentar desde lo teórico la relación entre trabajo metodológico, las competencias didácticas y el eslabón de base (año académico) a partir de su concreción en la clase para una formación crítica, humanista y social de los estudiantes. Se exponen las competencias didácticas, así como el contenido del trabajo metodológico en el eslabón de base. Esta relación hace más coherente el trabajo en la Universidad y se convierten en una herramienta de gran valía para lograr la calidad en el proceso de formación.
La educación superior en contextos carcelarios, el caso de la Ciudad de México
Authors: Díaz Pontones Mónica , Mora Gutiérrez Luis Ariosto
Published: April 2019

Se presentan algunos de los resultados más significativos de la investigación institucional realizada en torno a la educación superior en contextos carcelarios, el caso de la Ciudad de México. Su objeto de estudio fueron los significados, creencias, percepciones y expectativas de la formación universitaria de los estudiantes en situación de reclusión. El Programa de Educación Superior para Centros de Readaptación Social en el Distrito Federal (PESCER) de la Universidad Autónoma de la Ciudad de México (UACM), es una de las primeras experiencias de educación superior presencial en reclusión. Para la UACM la educación pública en su más amplia concepción busca integrar a la mayor cantidad de aspirantes independientemente de su situación social o económica y dar la oportunidad de educación superior a los sectores de la sociedad que menos oportunidad tienen. “Una institución de educación pública, así definida es aquella donde se tratan de eliminar las diferencias que acentúan la desigualdad”. En este sentido, y con el propósito de ofrecer apoyo a uno de los sectores marginados de la sociedad, la Universidad ha llevado su proyecto educativo al interior de los Centros de Readaptación del Distrito Federal, hoy llamado Ciudad de México, estructurando programas flexibles con la finalidad de incorporar al mayor número de interesadas/os y de reducir la exclusión provocada por los rígidos programas institucionales.
Aspectos teóricos para la gestión sostenible del turismo rural en la zona Sur de Manabí, Ecuador
Authors: Pin Figueroa Walter Jesús , Pita Lino Alexandra Elsy , Santos Moreira Vanessa Teresa
Published: April 2019

En este documento se analizan aspectos teóricos y metodológicos que aportan al diseño de un modelo de gestión sostenible de turismo rural en la zona Sur de la provincia de Manabí. Se realizó una búsqueda bibliográfica que permitió estudiar las especialidades del turismo rural, identificar sus principales particularidades y el modelo de desarrollo turístico en el cual se puede enmarcar, así como detallar los elementos centrales a considerar en el diseño e implementación de estrategias de intervención sostenibles para el territorio en el turismo rural cafetalero. Se reafirma la importancia y contribución del turismo a la economía ecuatoriana, considerando dos indicadores macroeconómicos básicos, el Producto Interno Bruto (PIB) y la generación de empleo. El estudio se desarrolló en el marco de las investigaciones del Programa Ecoturístico-forestal en el proyecto "Indicadores de sostenibilidad para la gestión ambiental enfocada al turismo. Fase 1. Referentes teóricos metodológicos” de la Universidad Estatal del Sur de Manabí, Ecuador.