IJOER : February 2016

Micromechanics of Thermoelastic Behavior of AA6070 Alloy/Zirconium Oxide Nanoparticle Metal Matrix Composites

Abstract The present work was deliberated to predict thermoelastic behavior of AA6070 alloy / ZrO2 nanoparticle metal matrix composites. ZrO2 is used is used in composite cutting tools and abrasive wheels. The RVE models were used to analyze thermo-elastic behavior. The stiffness of AA6070 alloy / ZrO2 nanoparticle metal matrix composites decreased with the increase of temperature. ZrO2 nanoparticles had undergone thermal shock at 300oC. The fracture was noticed at the interphase between AA6070 alloy and ZrO2 nanoparticles.

Keywords AA6070 alloy, zirconium oxide, RVE model, thermoelastic, finite element analysis.

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Role of Indian spices in cancer prevention: A Review

Abstract Indian Spices from time immemorial were considered with the philosophic concepts of improving health. Laboratory research has further demonstrated the effectiveness of a number of bioactive dietary components that have the ability to prevent cancer and other chronic diseases. Cytotoxic effects of numerous herbal extracts against cancerous cells have been reported. Research provides strong support for the future acceptance of natural compounds as chemo-preventive agents. In Indian cooking variety of spices are used for their specific delicious taste. Research on the health benefits of spices over the last century has elucidated the effects of spices as antioxidant, anti-inflammatory, anti-microbial, cardioprotective, neuroprotective and anti-cancer compounds. There has been a growing realization that spices possess anticarcinogenic properties which is supported by experimental evidences. Cancer chemoprevention is the inhibition or reversal of preinvasive carcinogenesis before cellular invasion across the basement membrane. The goals are to prevent incident precursors and cancer, regress prevalent precursors, and/or suppress recurrent precursors. The focus of cancer medicine in the 21st century is moving towards improved prediction of risk, prevention of disease, preservation of health, personalization of treatment, and more patient participation in decision-making.

Keywords Indian Spices, Cancer chemoprevention, Herbal Extracts.

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The design of the pipeline exhaust at high temperature of water heater pipeline flow channel system

Abstract This study is based on the experimental method to investigate the gas water heater cycling is connected to a short pipeline, new design piping system, The design of the pipeline exhaust at high temperature of water heater pipeline flow channel system, When the fluid passes through the shape changed flow field, under the effect of pressure distribution and geometric shape change of the flow field, The experimental results show that The design of the pipeline exhaust at high temperature can remove the water vapor pressure inside the thermal circulation pipeline, clear the flow path, and is corrosion resistant.

Keywords Water Heater, pipeline flow channel system, Fluid, Pipeline exhaust.

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An Overview of Novel Tetragonal Oxides with Enhanced High-Temperature Capabilities for Structural Applications

Abstract Tetragonal oxides possess great potential in structural applications because of the superior thermomechanical properties and corrosion resistance. This paper presents an overview of the structure and thermal properties of (Dy, Ce, Y)-doped ZrO2. The tetragonal structure is enhanced by doping Ce4+ cations to YSZ, whereas doping Dy3+ stabilizes the cubic phase. In comparison to conventional 8 wt.% Y2O3 stabilized ZrO2 (equivalent to 4 mol% Y2O3 stabilized ZrO2, 4YSZ), the thermal conductivity of 3Dy5Ce-YSZ and 2Dy-YSZ is decreased and the coefficient of thermal expansion (CTE) is increased, which are desirable for thermal barrier materials. The potential of Dy and Ce doped 4YSZ as thermal barrier materials for high-temperature applications has been highlighted in the paper.

Keywords thermal barrier coating materials, tetragonal structure, thermal conductivity, coefficient of thermal expansion

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Strategic and Operational Scope of Foreign Subsidiary Units

Abstract A foreign subsidiary unit formulates the scope of its strategic and operating activities based upon: (a) its MNC headquarters, (b) its host country and regional environments, (c) the global influences of its industry, (d) its own internal organizational environments, and (e) its own strategic leadership. Strategic and operational scope formulation process is vital to the successful unit goal accomplishments. An effective MNC would not be an “empire” model, but a “commonwealth” model.

Keywords Foreign subsidiary units, strategic and operational scope of MNC’s units, MNC competitiveness.

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DevOps Maturity Calculator DOMC – Value oriented approach

Abstract New style of IT puts many organizations in the current IT market under pressure to move their traditional delivery approaches towards modern mechanisms like DevOps. These new modern approaches consider the high demand rate of their clients who starve for having new features deployed to production every min to satisfy their needs especially with cloud computing and virtualizations become very common. Building on that needs, those organizations need to develop on their DevOps capabilities and invest on their resources skill set to cope with this new style of IT. Objective of this research work is to help those organizations to develop their DevOps capabilities and process maturity via designing a quantitative framework/tool that calculates the DevOps maturity level of the respective organization or project. This research is based on the work introduced in [Samer I. Mohamed] that describes the DevOps transformation framework. The proposed tool called DevOps Maturity Calculator or DOMC which measures the organization or project maturity level based on its level of maturity corresponds to each and every DevOps capability within the transformation framework introduced in [Samer I. Mohamed] DOMC introduces new set of features that enable organization to promote their business process by embed the DevOps maturity framework model along with set of metrics (KPIs, CSFs) to measure the current and expected mode of operation based on the organization targets/objectives..

Keywords Metric based, Transformation framework, Key Performance Indicator, Critical Success Factor, Maturity model.

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Controller Design for Nonlinear Networked Control Systems with Random Data Packet Dropout

AbstractThis paper investigates the state feedback control problem of nonlinear networked control systems in presence of data packet dropout. The random data packet dropout is modeled as a Bernoulli distributed sequence with a known conditional probability distribution. The closed-loop system model is obtained through the state augmentation method. The sufficient conditions for the existence of a state feedback controller are derived by means of Lyapunov stability theory such that the closed-loop control system is exponentially stable in the mean-square sense. The maximum bound of the nonlinear item of the control system is also obtained. Then a linear matrix inequality (LMI) based approach for designing such a controller which can be solved by Matlab LMI tool box is presented. Finally, a numerical simulation example is used to demonstrate the effectiveness of the proposed method.

KeywordsData Packet Dropout, Exponentially Mean-square Stable, Linear Matrix Inequality, Nonlinear.

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Alteration of pelvic floor biometry in different modes of delivery

Abstract

Objective: The objective of this study is to investigate and compare the effects of different modes of delivery on bladder neck mobility, anorectal angle and levator hiatus distensibility detected by ultrasound assessment.

Methods: Two hundreds nulliparous women were divided into two groups based on their type of delivery, vaginal delivery (VD) group and cesarean section (CS) group. The biometry of pelvic floor, including bladder neck mobility, anorectal angle and levator hiatus distensibility, in both groups of women was observed and compared at 6-8 weeks after delivery by perineal ultrasound assessment.

Results: On valsalva, the bladder neck mobility in the VD group was significantly increase, when compared with CS group (P<0.05). However, here was no significant difference between two groups at rest. The anorectal angle (ARA) was no significant differences between two groups at rest and on valsalva. Compared with the CS group, transverse diameters (LR), anteroposterior (AP) and levator hiatal area (LHA) of levator hiatus in VD group were significantly increased at rest and on valsalva (P<0.05)

Conclusion: Perineal ultrasound can objectively and movably detect pelvic floor dysfunction of women after different modes of delivery, and a normal VD may be a risk factor for pelvic floor dysfunction.

Keywords Pevic floor biometry; Delivery; Ultrasound.

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Comparative Study of Various Pre-Treatments Coupled to Vacuum Drying in Terms of Structural, Functional and Physical Properties of Carrot DaucusCarota

Abstract Different processes were studied as pretreatment operations in order to adequately intensify the drying of carrot. Blanching, freezing/thawing F/T, Steaming implying high saturated steam pressure and 120-s decompression time, Instant controlled pressure drop process (DIC) with pressure-drop time of about 0.02 s were studied. Their various texturing impacts were defined through the value of porosity ration J and the Scanning electron microscopy (SEM). More than the determination of the specific impacts of each considered pretreatment operation; correlations were established between various structural and functional parameters, and between drying performances and final product quality.

Keywords Carrot, Instant controlled pressures drop (DIC), Freezing/thawing, lipid content, carotene content, vacuum drying.

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Analysis of Vibro-Isolated Building Excited by the Technical Seismicity of Traffic Effects

Abstract— By location of a building in the vicinity of underground tube structure the effect of train operation excites the groundborne vibration. The solution of vibration transfer from the subsoil environment to the building structure is demonstrated using the example of a multistorey reinforced concrete building. The application of an elastic layer at foundation base level is used in order to eliminate excessive vibrations of these technical seismicity effects. The building is loaded by the non-stationary history of vibrations in accelerations. The measured time histories in acceleration were selected and then the typical history was used as an input for a dynamic analysis of the structure. Two 3-D numerical models of the building take into account the individual storeys, firstly modelled with vibro-isolation of building and secondly without this elastic part. The elastic layer was considered as the elastic subsoil of the Winkler-Pasternak model below the whole area of the upper part of the dual foundation plate and as the elastic support for columns and walls above the piles on the upper foundation plate level. The response prediction for vibro-isolated and non-isolated structure is compared and discussed. In the conclusion, the methodology of vibro-base isolation is evaluated.

Keywords Analysis, building, validation, vibro-isolation.

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Isomorphic transformation of the Lorenz equations into a single-control-parameter structure

Abstract An isomorphic structure that converts the Lorenz equations, whose dynamic properties are usually described in terms of three independent factors, into a single control-parameter system, is put forward and analyzed. Such an isomorphism is shown to bring an intrinsic simplification that offers much better depictions of the Lorenz non-linear dynamics, while it allows for quicker and forthright inspection of the control-parameter domains, inside which well-defined periodic, both symmetric and asymmetric, as well as chaotic solutions occur.

Keywords Lorenz equations, Fluid turbulence, Laser theory, Instabilities and chaos, Nonlinear dynamics

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Estimation of Rolling-Contact Bearings Operational Properties by Electrical Probe Method

Abstract The substantiation of an electrical probe method using for diagnostic real bearing units on a boundary state is given. The circuit diagram is developed and the way of estimation tribological properties of rolling-contact bearing races surfaces by means of electrical probe methods is offered. Correlation between parameters of conductance, mechanical strength and frictional metal surface characteristics is installed. It is shown, that application of the given methods allows to control the rolling-contact bearing state.

Keywords boundary lubricating layer (BLL), metal surfaces, contact resistance, dislocation structure, fracture mechanisms and surface deterioration, rolling-contact bearing.

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Thermo-mechanical fatigue behavior of a copper-alumina metal matrix composite with interpenetrating network structure

Abstract

The properties of interpenetrating metal-ceramic composites (IPC) may be designed following application requirements. High thermal conductivity combined with low thermal expansion, as well as high stiffness and high strength can be achieved. Such composites may be adequate materials to meet the requirements of thermally stressed components like heat sinks. For this purpose an interpenetrating copper-matrix composite was fabricated by squeeze-cast infiltration of porous alumina preforms. In this work a first approach into characterizing the Out-of-phase-TMF (OOP-TMF) behavior of such a composite is presented. For that purpose the composite is initially characterized by microstructural investigations, which showed a mostly homogenous distribution of metallic and ceramic phase, with randomly distributed coarse agglomerates of alumina. The OOP-TMF experiments were realized via inductive heating of the specimen and were conducted with maximum temperatures between 250 and 400 °C. The temperature- lifetime correlation from these experiments is presented and the cyclic deformation behavior was analyzed. A linear correlation between maximum temperature and specimen lifetime was found. Lifetime of nonreinforced copper was found to exceed the lifetime of the composite and was attributed to inner stress concentration due to mismatch of thermal expansion coefficients between copper and alumina and coarse alumina phases. Additional fractographic analyses revealed a crack initiation in surface-near areas and mostly with involvement of coarse alumina agglomerates.

KeywordsAlumina preform, cyclic deformation behavior, MMC, Squeeze Casting, TMF

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Online Tuning of the Fuzzy PID Controller using the Back-Propagation Algorithm

Abstract This paper presents a novel methodology for the online update the fuzzy rule base of the type-1 fuzzy logic system that estimates the proportional-integral-derivative (PID) gains of the professional PID control. Two different types of benchmarking PID controllers are used to compare the performance of the proposed methodology. The first controller is the so-called professional PID (P-PID), where the proportional gain KP, the integral gain KI, and the derivative gain KD, are offline calculated based on the dynamics of the process under control using the Zeigler Nichols method: in this controller the three gains remains fixed during the entire process control. The second controller uses three type-1 fuzzy logic systems to estimate each one of the gains of the professional PID controller every control cycle; each fuzzy rule base is offline estimated by the expert and remains fixed during the complete control process. This paper proposes a fuzzy self-tuning professional PID controller: it has three singleton type-1 fuzzy logic systems to calculate each gain of the controller every control cycle, with the novel characteristics that each fuzzy rule base is updated and tuned each feedback cycle using the back-propagation BP algorithm. This proposal is named the fuzzy professional proportional-integral-derivative controller (T1 SFLS P-PID) with back-propagation (BP) tuning. The experiments show that the proposed fuzzy self-tuning controller has better transient performance compared with the two benchmarking controllers. It shows the minimum overshoot and the minimum response time.

Keywords PID control, singleton type-1 fuzzy logic systems, back propagation algorithm.

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A Professional PID Implemented using a Non-singleton Type-1 Fuzzy Logic System to Control a Stepper Motor

Abstract This paper describes the stepper motor position control implemented using a novel non- singleton type-1 fuzzy logic system to update the gains of the professional proportional-integral-derivative controller running on ATMEGA 2560 microcontroller. In this work, three controllers are compared: a) the professional proportional-integral-derivative controller, b) the type-1 singleton fuzzy logic system coupled with the professional proportional-integral-derivative controller, and c) the novel type-1 non-singleton fuzzy logic system coupled with the professional proportional-integral-derivative controller. The experimental results show that the proposed controller has the best performance.

Keywords Fuzzy logic, Non-singleton, P-PID, singleton, stepper motor.

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The Microorganism Contamination Affect the Physical and Chemical Composition of Milk

Abstract

Background

The changes that occurred in the Brazilian dairy industry since 1990 began the advances in milk production observed in recent years and the greatest reflection of this transformation was the implementation of the new legislations. The somatic cell count (SCC) and total bacterial count (TBC) in milk are among the most discussed factors due to their importance in Brazil and related to losses at farms and industry. Studies evaluating the effect of TBC on the milk components are scarce and generally assess the effects of confounding between SCC and TBC. The objective of this study was to evaluate the milk from Zebu contamination by somatic cell count (SCC) and total bacterial count (TBC), isolated.

Material, Methods and Results

The samples were collected monthly from 180 farms in the Territory of Identity of the Middle Southwest Bahia. The samples were collected in the farms after manual milking and before cooling in sanitized plastic containers with a volume of 1 L. The contents of crude protein, fat, and lactose, SCC and TBC were determined electronically. Were formed 4 classes of the SCC and TBC. The up limit of the SCC was200,000 cells/ml were selected in order to evaluate only the effect of TBC on milk components, being classified in the same categories mentioned above. As the SCC increased, the contents of fat, crude protein, and total solids increased, an inverse behavior in relation to the content of lactose, which decreased. The TBC presented an inverse behavior, and, as it increased, the contents of fat, protein, and total solids decreased, however with no significant effect between the first and the last class.

Discussion

The increase in the content of crude protein in milk with high SCC is caused by the increase in serum proteins, especially the immuno-globulins; however, the fraction which is the most important for the dairy industry, the casein, decreases. The TBC results indicate that the country will face difficulty to produce milk and derivatives for export.Still, the TBC indicate that there are effects on the macrocomponents of milk, without a very clear behavior. However, the most adverse effects are observed in the degradation process of these. Two processes interact to decrease the content of lactose in the milk, i) mastitis, which causes reduced production in the mammary gland, and; ii) increased consumption by contaminant microbiota, with the increase of that population. The action of the contaminant microbiota on the macrocomponents of milk does not make the adverse effects very clear. The analytical method used in this study determines the protein fraction as a whole, as well as the lipid fraction. However, the protein fraction is divided in: i) casein (CN): α-s1-CN and α-s2-CN; β-CN, γ-CN; ii) serum protein: α-lactalbumin and β-lactoglobulin; iii) nonprotein nitrogen. Among these, casein is the most important for the dairy industry, and the SCC exerts negative effect on it. The proteolytic action of the enzymes produced by the natural microbiota of milk exists; however, with the contamination of the milk (mastitis, or microbial contamination after milking), this exogenous flora increases this proteolysis.In the lipid fraction in milk, there are: i) phospholipids; ii) cholesterol; iii) triacylglycerols; iv) diacylglycerols; v) free fatty acids; vi) monoacylglycerols; vii) free cholesterol; and others. In addition to evaluating the effects on the content of fat, it is necessary to know the effect of SCC and TBC on the lipid fraction.As related, both (SCC and TBC) are the principal factors related to milk quality, especially, TBC.

Conclusion

The somatic cell count and the total bacterial count negatively affect the physical and chemical composition of milk from zebu animals. Few studies were found in the literature that evaluated the effects of contamination of milk from zebu cows, which demonstrates the importance of this study.

Keywords cheese quality, dairy inefficiency, mastitis, milk contamination, zebu.

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Physical, chemical and sensory characteristics of cream goat cheese produced with Saanen and Alpine milk

Abstract The objective of this study was to evaluate the effect of inclusion of different protein sources in the diet of Saanen and Alpine goat on the physical and chemical parameters and sensory quality of cream goat cheese. The experimental design was based in double balanced 4×4 latin square (four animals by breed x four diets), with different protein sources: soybean meal (SBM), cottonseed meal (CM), cassava foliage hay (CFH) and leucaena hay (LH) in diets. The physical, chemical, texture and color parameters were not influenced (p>0.05) by feed, but the pH, fat, moisture and elasticity of the cheeses were influenced by breed. The levels of pH ranged from 4.24 to 4.43 and lactic acidity from 0.50 to 0.56g lactic acid/100g, fat from 12.31% to 17.85 and moisture ranged from 63.08 to 70.71%. The Alpine presented greater variability in the sensory profile, with the attributes softness, pasty, homogeneity, appearance, acid taste and goat milk taste presented highest variation due different animal. The Saanen presented the same sensorial profile for three animals, only one animal presented variation influenced by the attribute goat milk taste.

Keywords composition, nutrition, quality, sensorial profile.

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Mapping saline soils using Hyperion hyperspectral images data in Mleta plain of the Watershed of the great Oran Sebkha (West Algeria)

Abstract The hyperspectral optical imagery constitutes a significant mine of information. These images reveal valuable information about soil conditions and can be used successfully in the saline soils mapping domain.

Currently, the use of spatial hyperspectral image is considered to be a most spectacular technological revolution, because it has the advantage to reconstruct almost the entire spectrum of each images pixel. This characteristic, which is connected to the large number of bands, is achieved at the expense of the size of the image swath on the ground.

Only one scene satellite Hyperion image composed of more than two hundred twenty (220) images was used to cover the central part of the Mleta plain. These images are corrected on radiometric and atmospheric plan. The atmospheric corrections are made by FLAASH module using the MODTRAN radiative transfer model. This operation will subtract the values of absorbed radiation and layers atmospheric backscattered to find in the end the true reflectance values at ground level. The classification, based on almost continuous spectral information of the thematic objects across the electromagnetic spectrum, applied on these images will allow highlighting the different saline soils classes.

Two mapping methods have been used to mapping salinity. The first method is made from a colored composition between the first MNF (Minimum Noise Fraction) images. As for the second, it is done using a SAM (Spectral Angle Mapper) classification method based on information contained in the various spectral calculated from the image and compared with those of the spectral library.

Keywords Saline Soil, Hyperspectral Image, EO-1 Hyperion Satellite, Mleta Plain.

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Relationship between the Apex of Flexible Nail and the Level of Fracture: A Biomechanical Study

Abstract

Background

The use of flexible nails in paediatric femoral fractures is widely accepted. Flexible nails are uniformly bent in a C-shaped curve and apex (maximum curve of the nail) is matched to the fracture site. This biomechanical study analyzes how the relationship of the apex of the elastic nails to the level of the fracture influences the stiffness in a synthetic bone model.

Materials Methods

Twelve synthetic femurs were divided into three groups (n=4/group) depending on the level of fracture. Retrograde elastic nailing was performed with a pair of pre-bent C-shaped nails and inserted with the apex of the nail in middle of the shaft. We compared Group A (fracture 2.5cms distal to the middle of the shaft) group B (fracture in the middle of the shaft) and group C (fracture 2.5cms proximal to the middle of the shaft) using 4-point testing 90º (antero-posterior) and 0º (medio-lateral) to the plane of the nails.

Results

Group A showed significantly higher stiffness in antero-posterior and medio-lateral planes.

Conclusion

This study demonstrates that when the cortical entry point and the apex of the nails are on either side of fracture has highest stiffness characteristics.

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Numerical Study of Microbial Depolymerization Process with the Newton-Raphson Method and the Newton’s Method

AbstractComputational techniques are proposed for a numerical solution of an inverse problem that arises in a study of a microbial depolymerization processes. The Newton-Raphson method in conjunction with the Newton’s method is applied to a time factor that involves three parameters. The Newton-Raphson method reduces a system of three equations for three unknowns to a single variable equation, which is solved with the Newton’s method. Those techniques were applied to a microbial depolymerization process of polyethylene glycol. Introduction of experimental results into analysis leads to simulation of a microbial depolymerization problem.

Keywords Newton’s method, Newton-Raphson method, biodegradation, polymer, mathematical model, numerical simulation.

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Effects of soil physical and chemical properties on the distribution of trees in some ecological zones of Zalingei-Darfur; Sudan

Abstract This paper is part of a big research work on the analysis of woody vegetation and natural regeneration of some areas, as influenced by topography and distance from major wades at the study area. Inventories of tree species abundance, dominance and natural regeneration were made. Composite soil samples were taken from the seven identified ecological zones, the soil samples were analyzed for their chemical and physical properties. The distribution of tree species based on soil characteristic was analyzed. The soil texture of the study area was found to be sandy loam at lower hill slope (LH), Stony hill slope (SH) and lower terraces (LT). Sandy clay loam at sedentary plain (SP) and upper terraces (UT). Loamy sand at contemporary flood plain (CF). Clay at clay plain (CP) and. The soil pH is generally acidic. Faidherbia albida is the dominant tree species in Loamy sand and Sandy loam of (CF) and (LT). Balanites aegyptiaca dominant at the sandy clay loam of (UT). At sandy clay loam of (SP) and Sandy loam of (LH) the dominant species are Albizia amara and Acacia senegal. But Acacia seyal and Acacia Senegal dominant at the CP. Boswellia papyrifera and Albizia amara dominant at the sandy loam of SH. Result of Simpson diversity index showed that the most diversity site is at sandy loam of LT (0.15) , sandy loam of LH (0.26), SH (0.33), CP (0.34), sandy clay loam of SP (0.35), UT (0.41) and there is no diversity at loamy sand of CF. Generally there is no diversity in (CF). The (LT) have the highest diversity index of (0.15).

Keywords distribution, dominant , properties , soil , trees.

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Characterization of Musculoskeletal Disorders in the manufacturing industry in northwest of México

Abstract The aim of this work is to characterize occupational injuries in northwestern Mexico. To make this work resorted to the original source, the Mexican Social Security Institute (IMSS), who certifies labor lesions generated in the workplace. On the other hand, 706 workstations of the Manufacturing Industry were evaluated to determine the level of ergonomic risk. The results are: In the period between the years 2010-2014 its shows the increase of Musculoskeletal Disasters (MSD), from 84 in the year 2010 to 310 in 2014. The prevalence of injury is greater in women than in men. In the early years (2010-2012) the shoulder was the most affected part of the body, but in the entire series of years, the wrist has a positive trend that exceeds the shoulder in recent years. In reviewing injuries by industry can be seen that the wrist has prevalence in the electronics industry, the shoulder in the automotive industry, but MSD injuries decreased in the textile industry. Also a positive relationship between the data obtained from IMSS and assessments made in companies considering a correlation coefficient of 0.758 was found.

Keywords Ergonomics, Musculoskeletal Disasters, Manufacturing Industry, Northwest México

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Preparation and characterization of cross-linked polymer supports for catalysts immobilization

Abstract A series of macroporous cross-linked polystyrenes for applications as supports in catalysis have been synthesized and characterized in terms of their structural, thermal and morphological features. In this regards, we have shown how Fourier-transformed infrared spectroscopy mapping (µ-FTIR) may represent a very useful and easy-to-handle tool for the advanced spatial characterization of substituted cross-linked resins at a single bead level, thereby helping synthetic chemists in the prediction of their behavior during chemical processes. Further, scanning electron microscopy (SEM), thermal analysis (MTDSC), and N2 absorption (BET) measurements have been performed. Direct correlations between the polymerization conditions and resins chemical-physical properties have been identified.

Keywords Polymer catalyst supports; Green Chemistry; macroporous resins; polystyrene; micro-FTIR

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