bluuebunny/crossref_metadata_2025 huggingface dataset:
Spinning of Staple Hybrid Yarn from Carbon Fiber Wastes for Lightweight Constructions
Authors: Hengstermann Martin , Raithel Nadine , Abdkader Anwar , Cherif Chokri
Published: July 2015

The reuse of CF-wastes (rCF) is desirable due to the energy-intensive manufacturing, high price and the disposal problem of carbon fibers. It is a challenging process to spin yarn from rCFs in a short staple spinning production line which ensures a much higher strength later in the manufacturing of CFRP (carbon fiber reinforced plastics) parts than that of the parts from rCF-nonwovens or, from short-fiber reinforced injection molded parts. This spinning technology consists of several subsequent processes such as carding, drafting and spinning on a flyer frame. It is possible to produce hybrid yarn up to 2000 tex, which fineness is similar like a roving. The machines used to produce yarn for this purpose were specially modified and adapted, so that the brittle CF can be processed smoothly. Carded and draw frame slivers with different fiber lengths and mixing ratios were produced and later the high-quality hybrid yarn has been spun with different yarn twists.
Thermal Debinding of Ceramic-Filled Photopolymers
Authors: Pfaffinger Markus , Mitteramskogler Gerald , Gmeiner Robert , Stampfl Jürgen
Published: July 2015

Within the large variety of different additive manufacturing technologies stereolithography excels in high precision and surface quality. Using the Digital Light Processing (DLP) Technology a stereolithography-based system was developed, which is specifically designed for the processing of highly filled photopolymers.The powder-filled suspension enables the 3D-fabrication of a so called ceramic green part. In order to get a dense ceramic structure, subsequent thermal processing steps after the 3D-printing process are necessary. First, the polymer-ceramic composites heated up to 400°C. During this processing step, called debinding, the organic components are burned out. The resulting part, consisting of powder particles stabilized by physical interactions, is further heated to sinter the particles together, and the final, fully dense ceramic part is obtained.The debinding step is the most critical process. The used components have different evaporation or decomposition temperatures and behaviors. Thereby a reduction in weight and also in dimension occurs, which depends on the portion and composition of the organic components and especially on the temperature cycle. Furthermore, the physical characteristics of the ceramic powder, such as the particle size and the size distribution influence the debinding behavior. To measure the changes in weight and dimension a thermo-gravimetric (TGA) and a thermo-mechanical analysis (TMA) can be used. To avoid too high internal gas pressures inside the green parts a preferably constant gas evolution rate is seeked. Also the ‘surface-to-volume ratio’ affects the debinding characteristics. Therefore, optimized debinding cycles for specific geometries allow the crack-free debinding of parts with a wall thickness up to 20 mm.
Reinforcement Elements Aligned with the Direction of Forces for Load Transfer Areas of Long-Fiber-Reinforced Thermoplastic Components
Authors: Arnaut Katharina , Schiebel Patrick , Lang Anna , Herrmann Axel S.
Published: July 2015

Large-scale production of carbon fiber reinforced plastics often fails due to the increased material and manufacturing costs. Using the lightweight potential for competitive costs of materials, new construction methods are necessary, which enables an intelligent use of continuous fiber reinforcement, a largely automated production process as well as short cycle times. [1] The combination of continuous fiber reinforcement in the areas of maximum loads and cheaper materials such as long-fiber reinforced thermoplastic offers an efficient material application. Thereby, a required ratio of mechanical properties and attractive cost profile can be achieved.
New Sandwich Structures Consisting of Aluminium Foam and Thermoplastic Hybrid Laminate Top Layers
Authors: Nestler Daisy , Jung Heike , Trautmann Maik , Wielage Bernhard , Wagner Guntram , Drossel Welf Guntram , Drebenstedt Claudia , Hipke Thomas
Published: July 2015

Sandwich structures consist of one light core layer and two top layers, which form the load-bearing structure. These layers have to be stiff and strong and have to protect the structure against indentations. The main task of the core layer is to keep the top layers in place and to generate a high shear stiffness. In order to obtain the required space between the top layers, the core layer has to have a high specific volume. Different sandwich materials with aluminium or steel top layers and cores of aluminium combs, corrugated aluminium sheets or aluminium foams are already known. In order to obtain better properties in terms of strength fibre-reinforced plastics (FRP) are utilised as top layers; this is the focus of numerous of the current research studies. The sole use of these materials leads to negative effects regarding the damage and impact behaviour. New top layers with high strength and high stiffness characteristics as well as good damage tolerances are to be expected by utilising metal layers in combination with endless fibre-reinforced plastics, so called hybrid laminates. These hybrid laminates combine the positive properties of metals (e.g. ductility) and fibre-reinforced plastics (e.g. tensile strength). The focus of this investigation lies on the production and characterisation of sandwich structures with aluminium foam core layers and hybrid laminate top layers. The foam cores consist of closed pore aluminium foams produced by utilising ingot and powder metallurgical techniques. The top layers consist of glass fibre-reinforced thermoplastics and aluminium layers. The production of the sandwich materials is realised by means of thermal pressing.
The Edge Shear Test - An Alternative Testing Method for the Determination of the Interlaminar Shear Strength in Composite Materials
Authors: Weidenmann Kay André , Baumgärtner Lisa , Haspel Benedikt
Published: July 2015

The interlaminar shear strength is a characteristic value describing the mechanical behavior of composite materials such as laminates. Several methods for the determination of the interlaminar shear strength are described in open literature by several authors. Among these methods, the ILSS test (DIN EN ISO 14130) measuring the apparent interlaminar shear strength by using a modified bending test is the state of the art technique, as both the necessary testing equipment and the sample geometry are quite common. However, the ILSS tests implements shear loads indirectly by bending often leading to sample failure which is then not solely initiated by shear loads. Particularly for ductile matrices or those showing pronounced elastic behavior under bending, no interlaminar shear failure can be implemented and the interlaminar shear strength can not been determined or – if the user is not sensitized to the identification of non-shear failure behavior – the determined value is not correct.Up to now, alternative methods for determining the interlaminar shear strength implementing a shear load directly to the sample are quite elaborate regarding the test equipment to be used or the specimen preparation and geometry. In this contribution the authors present a novel test setup for an edge shear test which allows both a direct shear load and at the same time a reduced complexity of the specimen geometry which is comparable to those used in the ILSS test. The authors present results based on this novel testing method in comparison to conventional ILSS tests.
Process-Oriented Determination of Preform Permeability and Matrix Viscosity during Mold Filling in Resin Transfer Molding
Authors: Magagnato Dino , Henning Frank
Published: July 2015

The resin transfer molding (RTM) offers great conditions for mass production of fiber reinforced plastics. In this process, preformed fiber textiles are infiltrated with matrix material (for example: epoxy resin). During the infiltration, the matrix material starts a curing process until the complete consolidation. After the de-molding and a short post-processing step, the final part is ready to use. To reduce the cycle time for the RTM manufacturing, it is necessary to model and predict the flow behavior of the matrix material in a realistic way. An important parameter is the preform permeability, which characterizes the flow resistance of fibers against the flowing matrix material.In this study a new measurement setup is presented, which is able to determine the permeability directly during the manufacturing process, with integrated pressure and temperature sensors. This approach has many advantages against conventional measurement setups, that try to recreate the RTM process with a simple replication. With these replicas, it is only possible to simulate low flow velocities and pressures. Dynamic effects that occur at higher velocities cannot be regarded. Furthermore, the new setup has the advantage that measurement artifacts, like capillarity, have a lower impact. In addition to that, the infiltration can be done with a constant viscosity test fluid as well as with reactive matrix material. Thus, it allows further determination of the time depending viscosity.
Influence of In Situ Formed Tribolayer on Abrasive Wear Reduction
Authors: Varga Markus , Azhaarudeen Anifa Mohamed Faruck , Badisch Ewald
Published: July 2015

High temperatures (HT) are essential for many production methods. When operating with abrasives from natural sources, e.g. ores, abrasive wear is limiting the lifetime of core components. Material degradation and wear is accelerated in HT environments; wear protective solutions are necessary to minimize maintenance efforts. Especially, cost efficient solutions are needed in the industry, thereto in this research different Fe-based materials with prospective good HT wear pro­perties were chosen: i) austenitic stainless steel, ii) martensitic hot work tool steel, iii) carbide-rich ferrite MMC (metal matrix composite) and iv) complex alloyed hardfacing MMC. The materials were investigated by conducting high stress abrasion tests at temperatures up to 700°C. Wear rates were calculated and wear reducing effects by formation of mechanically mixed layers (MML) were studied. Two different technical approaches were carried out: SEM investigation of the surface coverage by abrasive embedding and optical microscopy analysis on cross-sections to determine the penetration depth of the abrasives. All materials except the hardfacing showed significant MML formation. Results showed increased coverage and penetration depth with ascending temperature. A wear reducing effect predominantly at HT is suspected, as MML forming materials showed shallower wear increase with temperature compared to the hardfacing.
Fatigue Delamination Growth in CFRP Composites: From Pure Mode I and Mode II to Mixed Mode I/II
Authors: Stelzer Steffen , Pinter Gerald
Published: July 2015

For composite design, it is desirable to have data covering the failure envelope from Mode I to Mode II. The existing standard procedures for quasi-static testing (ISO 15024 for Mode I and ISO DIS 15114 for Mode II) have recently been shown to be adaptable for the respective fatigue tests under displacement control. The Calibrated End-Loaded Split (C-ELS) test set-up developed for Mode II further allows performing a Fixed-Ratio Mixed Mode I/II (FRMM) test by simply inverting the loading direction compared to mode II.
Online Process Monitoring and Control by Dielectric Sensors for a Composite Main Spar
Authors: Breede Arne , Kahali Moghaddam Maryam , Brauner Christian , Lang Walter , Herrmann Axel S.
Published: July 2015

An online monitoring scheme to determine viscosity and permeability for a composite main spar infusion is presented. During the manufacturing process, defects such as dry spots and pores can occur and lead to poor part quality. In this study, dielectric sensors are used to create the information needed to model the process. Several experiments have been carried out to investigate the correlation between the sensors signal and the viscosity and to derivate constitutive equations. The provided data and the derived permeabilities are integrated into a simulation model of a cross section of the composite main spar. As a result, the real permeability can be identified. The knowledge of these parameters is one of the key aspects for a prediction of the resin flow and therefore for an improved process control.
Phase Change Detection in Neat and Fiber Reinforced Polyamide 6 Using Dielectric Analysis
Authors: Chaloupka Alexander , Wedel André , Taha Iman , Rudolph Natalie , Drechsler Klaus
Published: July 2015

In this study online-capable dielectric analysis techniques were investigated to show its potential on the example of detecting phase transitions of polyamide 6 (PA6) and its composites. The differential scanning calorimetry (DSC), a standard testing method commonly applied in thermophysical analysis, is used as a reference method throughout this work. Dielectric measurement techniques are introduced as a means for providing an online measuring concept that is able to monitor phasechanges in both neat, as well as glass and carbon reinforced PA6. Whereas a simple sensor setup has proven to be adequate for dielectric measurements of neat and glass reinforced PA6, the insertion of an additional insulation layer between sample and sensor was necessary to overcome short circuit problems induced through the conductive nature of carbon in carbon fiber reinforced PA6.Results show that crystallization and melting can be successfully identified using dielectric analysis and can be compared directly with results from the DSC. Analysis in the dielectric method is based on relative permittivity ϵ′, loss factor ϵ′′ and ion viscosity ρ. Here phase changes can be observed as a frequency dependent step in the measurement signal, which becomes increasingly apparent with increasing frequency. Plotting the first derivative of ϵ′, ϵ′′ and ρ relative to the temperature the phase change can be depicted in form of a peak, similar to the case of DSC. The derivative signals can be used as a direct means for monitoring in manufacturing processes.
Practical Results to the Long Term Behaviour of Fibre Reinforced Polymers under Constant Load
Authors: Zemann Richard
Published: July 2015

The long term behaviour of fibre reinforced polymers is important for many uses. In this publication experiments are described in which three different carbon fibre epoxy compound specimens, with different fibre orientations, are compared. For a comparison to metallic materials, as well as to get a benchmark, steel and aluminium specimens are also tested. All specimens are loaded with constant loads; the investigated load types are bending and torsion. In the experiments two different scenarios are investigated. The first scenario compares the creep behaviour under uniform start deflections and the second scenario compares the creep behaviour under uniform load conditions.
Strength and Stiffness Degradation of Carbon Fiber Reinforced Plastic under Cyclic Loading under Membran-, Shear- and Bending Loading
Authors: Haefele Peter , Herrera Oscar
Published: July 2015

In order to meet the increasing lightweight requirements, the application of fiber reinforced plastics is indispensable. To ensure the structural durability of the car or machine under operational conditions, it is essential to know the long term behavior of carbon fiber reinforced plastic material (CFRP) under the numerous influencing factors under fatigue loading. For a reliable safety assessment of the car structure under operational conditions, the degradation of the stiffness and of the static strength after a certain damage due to cyclic loading is of particular importance. The paper covers the loss of stiffness and remaining strength as a function of fatigue damage for specimen and components under membrane, shear and bending loading. The tests are done using different layer set-ups (unidirectional, angle ply, quasiisotropic) and various loading conditions (membrane, shear and bending loading). In order to account for the transferability, the tests are carried out using specimen and components (hat sections). Both specimen and components show a significant loss in strength and stiffness.
Our percutaneous nephrolitotomy experience in patients with horseshoe kidney
Authors: Suelozgen Tufan , Isoglu Cemal Selcuk , Turk Hakan , Yoldas Mehmet , Ilbey Ozlem Yusuf , Zorlu Ferruh
Published: July 2015

Objectives: Horseshoe kidney is the most common renal congenital fusion anomaly. Kidney stone formation is more common in horseshoe kidneys and some of them requires surgical procedure. So we want to evaluate the results of PNL in patients with horseshoe kidney anomaly.
Matherial and method: Between January 2009-January 2014 PNL operation was performed in 6 patients with horseshoe kidney anomaly in our clinic. Success of surgery and postoperative/peroperative complications were evalutaed retrospectively.
Results: No severe complications occured in any patient caused by surgery. Three patients became stonefree. One patient had less than 4 mm. residual stone, two patients had more than 4 mm. residual stone.
Conclusion: PNL is safe surgical method and it can be performed successfully in patients with horseshoe kidney anomaly.
Evaluation of Tl-201 SPECT imaging findings in prostate cancer
Authors: Ozyurt Sinem , Koca Gokhan , Diri Akif , Demirel Koray , Karakan Tolga , Resorlu Berkan , Korkmaz Meliha , Germiyanoglu Cankon
Published: July 2015

Objectives: To compare with histopathological findings the findings of prostate cancer imaging by SPECT method using Tl-201 as a tumor seeking agent.
Methods: The study comprised 59 patients (age range 51-79 years, mean age 65.3 ± 6.8 years) who were planned to have transrectal ultrasonography (TRUS)-guided biopsies due to suspicion of prostate cancer between April 2011 and September 2011. Early planar, late planar and SPECT images were obtained for all patients. Scintigraphic evaluation was made in relation to uptake presence and patterns in the visual assessment and to Tumor/Background (T/Bg) ratios for both planar and SPECT images in the quantitative assessment. Histopathological findings were compatible with benign etiology in 36 (61%) patients and malign etiology in 23 (39%) patients. Additionally, comparisons were made to evaluate the relationships between uptake patterns,total PSA values and Gleason scores.
Results: A statistically significant difference was found between the benign and malignant groups in terms of uptake in planar and SPECT images and T/Bg ratios and PSA values. No statistically significant difference was found between uptake patterns of planar and SPECT images and Gleason scores in the malignant group.
Conclusions: SPECT images were superior to planar images in the comparative assessment. Tl-201 SPECT imaging can provide an additional contribution to clinical practice in the diagnosis of prostate cancer and it can be used in selected patients.
Lower urinary tract symptoms associated with neurological conditions: Observations on a clinical sample of outpatients neurorehabilitation service
Authors: Torelli Fabrizio , Terragni Erica , Blanco Salvatore , Di Bella Natale , Grasso Marco , Bonaiuti Donatella
Published: July 2015

Objectives: The overall aims of this study were to investigate the lower urinary tract symptoms (LUTS) associated with neurological conditions and their prevalence and impact on a clinical sample of outpatients of a neurorehabilitation service. Materials and methods: We reviewed the files of 132 patients treated in our neurorehabilitation service from December 2012 to December 2013. Patients were divided into several subgroups based on the neurological diagnosis: Multiple Sclerosis (MS), other demyelinating diseases, Peripheral Neuropathy, neurovascular disorders (ND), neoplastic disease, traumatic brain injury (TBI), Parkinson and Parkinsonism, spinal cord injuries (SCI). Urinary status was based on medical evaluations of history of LUTS, type, degree, onset and duration of symptoms. We tried to analyze prevalence, kind of disorder, timing of presentation (if before or after the neurological onset) and eventual persistence of urological disorders (in the main group and in all subgroups). Results: At the time of admission to our rehabilitation service, LUTS were observed in 14 out of 132 cases (11%). A high proportion of these outpatients (64.2%) presented bothersome urinary symptoms such as incontinence, frequency and urgency (storage LUTS). The most frequent symptom was urinary urge incontinence (42.8%). This symptom was found to be prevalent in the multiple sclerosis and neurovascular disorders. In 93% the urinary symptoms arose as a result of neurologic conditions and 78.5% did not present a complete recovery of urological symptoms in spite of improved selfreported functional activity limitations. None of these patients performed urological rehabilitation. Conclusions: Neurological disorders are a significant issue in rehabilitation services and it can lead to lower tract dysfunction, which causes LUTS. Storage symptoms are more common, especially urge incontinence. Current literature reports that a further optimization of the rehabilitation potential of neurologically ill patients is possible through an implementation of urological basic measures into the neurological treatment routine.
Internal urethrotomy versus plasmakinetic energy for surgical treatment of urethral stricture
Authors: Ozcan Levent , Polat Emre Can , Otunctemur Alper , Onen Efe , Cebeci Oğuz Ozden , Memik Omur , Voyvoda Bekir , Ulukaradag Emre , Ozkan Tayyar Alp , Sener Murat , Ozbek Emin
Published: July 2015

Purpose: we aimed to compare the longterm outcome of surgical treatment of urethral stricture with the internal urethrotomy and plasmakinetic energy. Material and Methods: 60 patients, who have been operated due to urethral stricture were enrolled in our clinic. None of the patients had a medical history of urethral stricture. The urethral strictures were diagnosed by clinical history, uroflowmetry, ultrasonography and urethrography. The patients were divided two groups. Group 1 consisted of 30 patients treated with plasmakinetic urethrotomy and group 2 comprised 30 men treated with cold knife urethrotomy. Results: There were no statistically significant differences between two groups in terms of patient age, maximum flow rate (Qmax) and quality of life score (Qol) value. A statistical difference between the two groups was observed when we compared the 3rd-month uroflowmetry results. Group 1 patients had a mean postoperative Qmax value of 16,1 ± 2,3 ml/s, whereas group 2 had a mean postoperative Qmax value of 15,1 ± 2,2 ml/s (p < 0.05). In the cold knife group, 3 of 11 (27,7%) recurrences appeared within the first 3 months, whereas in the plasmakinetic group zero recurrences appeared within the first 3 months in our study. The urethral stricture recurrence rate up to the 12 month period was statistically significant for group 1 (n = 7, 23%) compared with group 2 (n = 11, 37%) (p < 0.05). Conclusion: We believe that plasmakinetic surgery is better method than the cold knife technique for the treatment of urethral stricture.
Recurrence of sigmoid colon carcinoma in the retained urethra after cystectomy: A case report and review of the literature
Authors: Yagihashi Yusuke , Arakaki Yoshitaka
Published: July 2015

Urethral recurrence arising from a primary colorectal adenocarcinoma is rare. Here, we report a case of urethral recurrence of sigmoid colon cancer, which developed after cysto-prostato-sigmoidectomy for sigmoid colon cancer invading the bladder. The patient underwent urethrectomy successfully and is currently tumor-free. Surgeons who follow patients with colorectal cancer invading the bladder should be aware of this case. The early detection of recurrence improves the chances for disease-free survival.
Lower pole renal cut injury due to the iliac wing fracture: A rare case report
Authors: Yildirim Çaglar , Yüksel Özgür Haki , Akan Serkan , Ürkmez Ahmet , Verit Ayhan
Published: July 2015

The most frequent causes of blunt genitourinary injuries are falls from heights, motor vehicle accidents and sports injuries. Firearm injuries and penetrating stab wounds are also frequently encountered. Skeletal system traumas in the vicinity of the urogenital system can cause urological organ injuries. Though rarely, renal traumas can be dependent on the kinetic energy of the trauma and the retroperitoneal movement capacity of the kidneys and cannot be explained with the proximity of the kidney to the skeletal system. In cases with high-energy decelerations, renal pedicle and ureteropelvic junction traumas are more frequently observed. Herein, we presented a grade 3 left kidney lower pole injury developed secondary to A2 type pelvic fracture following a high energy deceleration trauma. It should not be forgotten that especially in this type of fractures, injuries of the lower renal pole can occur.
Letter to Editors about Rare case of intra-testicular adenomatoid tumour
Authors: Fabiani Andrea , Maurelli Valentina , Filosa Alessandra , Fioretti Fabrizio , Mammana Gabriele
Published: July 2015

Not available.
A new entropy model for RNA: part V, Incorporating the Flory-Huggins model in structure prediction and folding
Authors: Dawson Wayne , Kawai Gota
Published: July 2015

The effect of solvent-biopolymer interactions is hardly negligible. Whereas the ideal (non-interacting) polymer consisting of N monomers in an ideal solvent is expected to have the terminal ends of its chain with a root-mean-squared (rms) end-to-end separation distance (rms) proportional to the square root of N, real interactions of a rms polymer both with itself and with the solvent often tend to strongly perturb rms. In rms poor solvent, the biopolymer can collapse into a small globule much smaller than the ideal rms due to excluding solvent. In good solvent, the biopolymer can swell to a size much larger than the ideal r due to favoring solvent. These effects require rms corrections to an ideal polymer equation. We have been developing the cross linking entropy (CLE) model in this series. The model attempts find the maximum entropy of a folded polymer by taking into account the correlation caused by bonding and other interactions of the structure. In RNA, this mostly occurs in the stems. Here we adapt CLE model to handle polymer swelling and collapse for RNA molecules both in good and in poor solvent. This work is intended to introduce this type of study and to allow its systematic application in problems of RNA folding and structure prediction. The current study suggests that there may be some tendency for RNA to behave as a polymer in poor solvent and that this collapse may happen in sequences longer than 50 nt.
Short Communications
Authors: Authors The
Published: July 2015

- Extinct or not extinct: the case of the Chalcides ocellatus(Squamata: Scincidae) population from the Park of the ex Bourbonic Royal Palace of Portici (Naples, Italy)

- Petrochirus fabroensis Pasini, Garassino & De Angeli, 2014 (Anomura, Diogenidae) and Ranina sp. (Brachyura, Raninidae) from the Pliocene of Masserano (Piedmont, NW Italy)

- Ranina sp. (Brachyura, Raninidae) from the Pliocene sands of “Serre di Rapolano” (Siena, Tuscany, central Italy)

- Esemplari di lince Lynx lynx (Linnaeus, 1758) dalle Alpi Orientali del XIX secolo in musei italiani
Effect of glycerol in combination with alfalfa on in vitro gas production and microbial protein synthesis
Authors: Alfonso-Ávila Á. R. , Charbonneau E. , Lafrenière C. , Berthiaume R.
Published: July 2015

Alfonso-Ávila, Á. R., Charbonneau, E., Lafrenière, C. and Berthiaume, R. 2015. Effect of glycerol in combination with alfalfa on in vitro gas production and microbial protein synthesis. Can. J. Anim. Sci. 95: 577–588. This study sought to determine the effect of added glycerol on microbial protein synthesis, ruminal degradation and utilization of alfalfa at different concentrations of nonstructural carbohydrates (NSC), using in vitro gas production. The 2×3 factorial plus one treatment consisted of oven-dried alfalfa with two NSC levels [high: 17.9 (HNSC) or low: 7.4% dry matter (DM) (LNSC)] and three glycerol treatments [control without glycerol, 15% crude glycerol (CG) and 15% pure glycerol (PG)], the additional treatment was LNSC+exogenous sugars (LNSC+ES: LNSC with 5% sucrose+5% starch). Five pre-planned contrasts were evaluated from the seven treatments: (1) HNSC vs. LNSC alfalfa; (2) with glycerol vs. without; (3) interaction of alfalfa and glycerol; (4) CG vs. PG, and; (5) LNSC+ES vs. HNSC. Gas production over 24 h was higher for HNSC than LNSC (202 vs. 179 mL g−1 DM) and with glycerol than without glycerol (202.2 vs. 168 mL g−1 DM). A decrease in the acetate:propionate ratio was observed for HNSC compared with LNSC (2.87 vs. 3.27) and for the addition of glycerol vs. no glycerol (2.78 vs. 3.65). Reduced microbial mass (185.5 vs. 240.5 mg g−1 DM) was observed for CG compared with PG. The LNSC+ES treatment had lower microbial protein synthesis and propionic acid production in relation to HNSC. No significant interaction was observed between the effect of NSC content of alfalfa and glycerol utilization. When effects were studied separately, results indicate that increasing NSC in alfalfa stimulates the synthesis of microbial protein. Also, the addition of glycerol promotes the synthesis of glucose precursors. Finally, the type of glycerol has an impact on results obtained suggesting caution when extrapolating results for PG to CG.
Short Communication: Birdsfoot trefoil as a preventative treatment for gastrointestinal nematodes in pastured dairy heifers
Authors: Shepley E. , Vasseur E. , Bergeron R. , Villeneuve A. , Lachance S.
Published: July 2015

Shepley, E., Vasseur, E., Bergeron, R., Villeneuve, A. and Lachance, S. 2015. Short Communication: Birdsfoot trefoil as a preventative treatment for gastrointestinal nematodes in pastured dairy heifers. Can. J. Anim. Sci. 95: 533–537. Bioactive forages, such as birdsfoot trefoil, may serve as an alternative to anthelmintic drugs in pastured dairy heifers. Differences in parasite burden and growth were examined between eight treatment heifers fed a birdsfoot trefoil mixture and nine control heifer fed alfalfa silage 45-min per day for 12 wk. A significant 3.8- to 9.4-fold reduction in fecal egg counts was observed for treatment heifers at weeks 5, 9, 11 and 12. No treatment effect was found for weight gain. Our results suggest that birdsfoot trefoil may reduce parasite fecal egg counts in pastured dairy heifers without detrimental impact on growth.
Evaluation of the performance of sorghum genotypes using GGE biplot
Authors: Gasura Edmore , Setimela Peter S. , Souta Caleb M.
Published: July 2015

Gasura, E., Setimela, P. S. and Souta, C. M. 2015. Evaluation of the performance of sorghum genotypes using GGE biplot. Can. J. Plant Sci. 95: 1205–1214. In spite of sorghum's drought tolerance, it is largely affected by genotype×environment interaction (GE), making it difficult and expensive to select and recommend new sorghum genotypes for different environments. The objectives of this study were to examine the nature of GE for sorghum grain yield, to identify superior sorghum genotypes for sorghum production environments and determine ideal testing locations for future breeding activities in Zimbabwe. The grain yield of 20 sorghum genotypes from Seed Co. Pvt. Ltd. were evaluated for 2 yr (2011/2012 and 2012/2013 cropping seasons) at five locations in different agro-ecological zones of Zimbabwe. Combined analyses of variance showed significant differences for genotypes (P<0.01), environments (P<0.001) and genotype×location (P<0.01). Genotype×environment variance component was seven times greater than that of genotypes. Genotype×environment interaction was attributed to the variability in the predictable biotic and abiotic factors associated with the different locations. The genotype main effect plus GE biplot showed that the experimental sorghum genotypes W07, W09, W05, G06 and OP46 were high yielding and stable, and possessed other desirable agronomic traits. The most discriminating and representative location was Rattray Arnold Research Station.
Addressing Uduma’s Africanness of a Philosophy Question and Shifting the Paradigm from Metaphilosophy to Conversational Philosophy
Authors: Chimakonam JO
Published: July 2015

This conversation is inspired by Uduma O. Uduma’s essay entitled “The Question of the ‘African’ in African Philosophy: In search of a Criterion for the Africanness of a Philosophy”. In this essay, Uduma coined what he calls “the Africanness of a Philosophy Question which consists in the ultimate criterion for African philosophy. He was not the first to dwell on the Africanness issue in African philosophy but he was the first, to my knowledge, to christen it as such. Before Uduma framed the question into a proper metaphilosophical concern in African philosophy, old campaigners like Paulin Hountondji, Odera Oruka, Peter Bodunrin, Kwasi Wiredu,Sophie Oluwole, Innocent Onyewuenyi, etc., have all dwelt on it with some going more in-depth than others. I have also dwelt partly on this question before in an essay entitled “The Criteria Question in African Philosop hy: Escape from the Horns of Jingoism and Afrocentrism”. Incidentally, my treatment of the issue was not digestive enough as I did not mention the likes of Bodunrin, Wiredu, Oluwole and even Uduma himself—a terrible short-sightedness—one that I wish to correct in this discussion. My first aim in this work is to attempt to settle this metaphilosophical vicious circle once and for all. On the basis of this, I wish also to orchestrate a shift from the vicious circle of metaphilosophical engagements to a more f ruitful conversational engagement in contemporary African philosophy. Our method shall consist in critical conversationalism.Keywords: Africanness question, African philosophy, criteria question,metaphilosophy, conversational philosophy
Postmodernism and the Objectivity of the Social Sciences: An Interrogative Conversation with Augustine Atabor
Authors: Nweke VCA
Published: July 2015

No Abstract
Efectos de la discretización en la simulación de escorrentía urbana
Authors: Macor Jose Luis , Pedraza Rául A.
Published: July 2015

La urbanización produce un fuerte impacto sobre las respuestas hidrológicas de las cuencas. El incremento de la impermeabilidad aumenta notablemente los escurrimientos superficiales. Para evacuar los excedentes pluviales urbanos, se diseñan y construyen sistemas de drenaje, utilizando modelos matemáticos que permiten realizar los cálculos de diseño, operación y planificación de tales sistemas. El avance de la informática ha generalizado la aplicación de la modelación distribuida, lo que supone una mejora de la descripción de los fenómenos que participan en la transformación lluvia-escorrentía. Sin embargo, incorpora una incertidumbre relacionada con la elección del tamaño de la discretización superficial apropiada para la simulación. Este trabajo examina los efectos de la discretización espacial sobre la simulación del escurrimiento en una red de conductos pluviales, analiza la variación del parámetro de calibración W para diferentes escalas espaciales de una cuenca urbana y propone criterios para elegir la mayor escala espacial que satisfaga una precisión deseada en los resultados. Para ello se realizaron ensayos numéricos con el modelo SWMM sobre una cuenca urbana teórica y sobre una cuenca urbana experimental. A partir de los resultados obtenidos, se observa que la escala espacial influye en los resultados de la simulación con el modelo SWMM. La red de renaje adiciona almacenamiento al sistema, atenuando y retardando los caudales pico. A medida que aumenta la escala una parte de la red es removida y en consecuencia se empuntan los hidrogramas y se anticipan los picos. Para que el modelo represente, a una escala mayor, una función de respuesta similar a la obtenida con la escala de detalle, es necesario compensar la pérdida de almacenamiento. Para ello, se debe reducir el ancho total de la cuenca, es decir, aumentar la longitud de escurrimiento. Para aplicaciones del modelo SWMM en cuencas similares a la del estudio, una vez discretizada la cuenca y si no se dispone de información pluvio-hidrométrica, se puede estimar el valor medio del parámetro W a partir de la relación ancho medio de escorrentía - área media de subcuencas. Para la cuenca experimental estudiada la escala espacial más grande que conserva la precisión admisible de los hidrogramas a la salida y de niveles de agua en nodos de interés es la meso escala.
Estudio de las reglas de explotación de los embalses del sistema Cantareira, Sao Paulo Brasil
Authors: Silva Peixoto Luciana , Fábio Mauad Frederico , Andreu Álvarez Joaquín
Published: July 2015

El rendimiento de un sistema de recursos hídricos es analizado, a través de simulación computacional, considerando diferentes políticas de operación de los embalses. Son utilizados indicadores de rendimiento (garantía, resiliencia, déficit máximo y medio) en la comparación de las diferentes estrategias de operación. Los resultados obtenidos en las simulaciones están, en general, de acuerdo con estudios similares desde el punto de vista de los criterios de rendimiento. Se ha encontrado que la regla de operación, definida en la “Portaría” del Departamento de Aguas y Energía Eléctrica-DAEE Nº 1213, proporciona mejores resultados en relación a la vulnerabilidad, a costa de una mayor frecuencia de fallos.
Interpretazione multifrattale dei tratti vallivi dei corsid'acqua Calabresi
Authors: De Bartolo Samuele G. , D'Ippolito Antonio , Veltri Massimo
Published: July 2015

Se realiza una Investigación sobre el comportamiento multifractal en la parte final de algunos cursos fluviales de Calabria (sur de Italia). Esta investigación se ha llevado a cabo mediante la utilización del Método de la Integral de Correlación Generalizada. 
Estrategias de eliminación de sulfuro de hidrógeno con el reactivo IBS® en un reactor biopelícula
Authors: Cacho Rasillo L. , Amieva del Val J.J. , Tejero Monzón I.
Published: July 2015

Los olores debidos a compuestos del azufre son un problema en conducciones y depuradoras de aguas residuales. Ciertas condiciones que se ocasionan en estos medios favorecen la formación de sulfuro de hidrógeno, principal gas maloliente que plantea problemas técnicos debidos a su corrrosividad y toxicidad, así como quejas sociales al ser fácilmente detectado por el sistema olfativo humano. Este trabajo estudia la eliminación de olores en un reactor biopelícula de laboratorio utilizando un compuesto químico (proporcionado por la empresa ACIdEKA S.A.) inhibidor de la actividad de la biomasa sulfato-reductora. Su eficacia se estudia variando la concentración, los modos de adición y el tiempo entre dosis. Por otro lado se investiga la posible aclimatación de la biomasa al reactivo. Se consiguen rendimientos máximos de eliminación de olor (SH2 y mercaptanos) cercanos al 99%, utilizando dosis de 18,6mg·g-1Biopelícula húmeda y adicionando de forma continua, no encontrándose indicios de aclimatación por parte de la biomasa al producto.
Programación del riego en cítricos con base en sensores de medida del estado hídrico del suelo y de la planta.
Authors: Vélez Sánchez J.E. , Sebastiano Intrigliolo D. , Castel Sánchez J.R.
Published: July 2015

Se ha realizado un experimento de riego deficitario en una parcela de “Clementina de Nules/Citrange carrizo” en el que se estudiaron tres programaciones diferentes de riego por goteo basadas en: i) información del suelo (Watermark), ii) de la planta (dendrómetros) y iii) riego deficitario fijo. Todas ellas se compararon con un control bien regado durante todo el año al 115% de la evapotranspiración de un lisímetro de pesada (ETlis) situado en la misma parcela. Los tratamientos diferenciales de riego, se aplicaron tras la caída fisiológica de frutos, durante el periodo de crecimiento del fruto, desde mediados de julio hasta octubre. Durante el resto del año todos los tratamientos se regaron al 115% de la Etlis. Al tratamiento regado con base en la información de la planta (MCD1.25) se le aplicó semanalmente un volumen de agua variable para mantener la máxima concentración diaria del tronco (MCD) en torno al 125% de la del control. Mientras fue posible programar el riego para mantener el valor del MCD en un 125% de la del control, en el tratamiento WMK, los sensores no respondieron a los ciclos de secado y hunedecimiento por lo que no se pudo regar dicho tratamiento en base a los umbrales establecidos. Ningún tratamiento de riego difirió significativamente del control en cuanto a producción y calidad de la fruta, obteniéndose ahorros de agua en todos ellos cercanos a un 30%. Por lo tanto, no queda demostrado el valor añadido de regar en función de la información derivada de los dendómetros.
La ingeniería y la gestión del agua de riego en Al-Andalus
Authors: Roldán Cañas J. , Moreno Pérez M.F.
Published: July 2015

Muchas de las tecnologías introducidas por los árabes en al-Andalus tienen origen romano o principalmente oriental, siendo estas utilizadas para mejorar el manejo y aplicación del riego, y para llevar el agua a las ciudades. Sin embargo, los árabes comienzan una etapa próspera respecto de la agricultura, desde el siglo ocho. La práctica del riego fue mejorada y extendida en todo el territorio islámico incluyendo al-Andalus. Entonces, la civilización islámica desarrolla y mejora las técnicas conocidas desde la antigüedad. Las mejoras fueron basadas en la necesidad de una correcta distribución del agua y de su mejor aprovechamiento, y con el imperativo de evitar conflictos relacionados con esta. Algunas de las reglas comunes son: distribución de agua proporcionalmente a la cantidad de tierra poseída; responsabilidad individual de los regantes en aspectos tales como mantenimiento del canal, aceptación de los turnos de riego y compensación de los posibles daños provocados a los vecinos; y carácter autónomo de los regadíos de modo que la justicia sea realizada internamente por sus propias instituciones de autogobierno, aunque dependiendo jurisdiccionalmente del juez o cadí general. En conclusión los árabes realizaron una expansión de las técnicas agrícolas orientales incluyendo el regadío, hacia el oeste del mediterráneo. Finalmente, al-Andalus se convierte en un nuevo foco de difusión con vuelta al norte de Africa y , posteriormente, hacia América. Su civilización, quizás poco innovadora, preservó perfeccionó e intensificó, en cambio, tecnologías que, de otro modo, no habrían llegado al mundo occidental y que, en algunos casos, habían desaparecido durante los siglos anteriores.
Uso sustentável da água e convivência com a escassez: revisitando conceitos e indicadores.
Authors: Santos Pereira L.
Published: July 2015

A sustentabilidade do uso da agua tem implicações ambientais, tecnolóicas, económicas e sociais que imlican conservação e poupança, quer pela necessidade de considerar a convivência com a escassez, quer no que se refere à qualidade da agua. Considerando os regimes de escassez, uns devidos a causas naturais, a aridez e as secas, outros com causas antrópicas, a desertificação e a penúria, aborda-se a dinâmica dos usos, evidenciando que parte dos problemas de escassez resultam do insuficiente controlo da procura. Assim, analisam-se alguns conceitos que estão na base do uso sustentável da água, distinguindo usos e consumos, perdas e desperdícios, usos benéficos e não benéficos e formulando-se uma aproximação aos caminhos para tornar mais eficiente o uso da água em regadio, incluindo a produtividade da água. Consequentemente, propõem-se indicadores apropriados que substituam o uso generalizado do termo “eficiência”, tantas vezes mal usado e mal interpretado. Visando a conservação e poupança de água, abordam-se diversas medidas que a ambas se referem, nomeadamente educação, formação, colaboração institucional, informação e participação. Finalmente analisa-se a problemática dos impactos do “preço” da água como medida indutora de conservação e poupança em regadío , concluindo-se pela necessidade de uma abordagem diferenciada em relação com as condições produtivas a que se pretende aplicar; além disso propõe-se que o valor da água substitua o preço da água, isto é, que se valorize a água e os seus usos de uma forma completa, considerando os valores económicos em conjunto com os ambientais, sociais e culturais.
Risco Associado à ruptura por calgamento de barragens em aterro
Authors: Brito dos Santos J. , Franca M.J. , Betâmio de Almeida A.
Published: July 2015

O enorme potencial destrutivo que constitui o volumen de agua armazenado numa albufeira induz un factor risco no vale a jusante de uma barragem. O conceito de risco assenta na estimativa de probav¡bilidades de ocorrência e danos provocados pelo acidente, conduzindo à necessidade de modelação de fenómenos. O presente artigo aborda a modelação física e matemática e a análise de incertezas aos modelos de ruptura de barragens no ámbito da análise do risco. Ao tratar-se da condição de frontera a montante na análise de propagação de cheias, a modelação física e matemática da ruptura de barragens constitui a base da análise do risco. A modelação da ruptura de barragens não se trata de uma modelação determinística; os resultados provenientes da modelação transportam incertezas de natureza epistémica e aleatória que devem ser integradas na análise do risco. Neste documento apresentam-se resultados provenentes de um estudo experimental e numérico de ruptura de barragens em aterro, assim como resultados da aplicação de um método de propagação de incertezas (probabilidades) a um modelo de ruptura de barragens.
Desafíos do setor elétrico brasileiro
Authors: Biazetti Prefeito L.F.
Published: July 2015

A reestructuração do sector elétrico brasileiro, iniciado em meados da década de 1990, deve ser vista dentro de uma perspectiva histórico-estrutural, envolvendo em uma mesma análise a privatização, a crise do setor elétrico e a garantia à cidadania. Para entender as reformas ocorridas no setor, é necessário evidenciar um pouco da trajetória histórica do setor, vocação hidrelétrica, as opções político-econômicas para a reestructuração em curso e as respostas dadas pelo governo à crise elétrica brasileira.
Sedimentación de finos en el entorno del embalse de Salto Grande en el Río Uruguay
Authors: Mangini S. , Prendes H. , Huespe J. , Amsler M. , Piedra Cueva I.
Published: July 2015

La Universidad Nacional del Litoral (Santa Fe, Argentina) y la Universidad de la República (Montevideo, Uruguay), realizaron mediciones y estudios relacionados con un control de la sedimentación en el embalse de Salto Grande, sobre el Río Uruguay. El trabajo cumplió con el doble propósito de: por una parte, atender a un servicio técnico; y por otra, obtener información imprescindible para el desarrollo de proyectos de investigación y de una tesis de doctorado, sobre sedimentación de limos y arcillas en ambientes fluviales. En el presente artículo se describen resumidamente los estudios realizados, se analizan los resultados obtenidos y presenta la morfología y dinámica muy particular de los depósitos acumulados en determinados sectores localizados en el antiguo cauce, dentro del embalse. Además, se aportan conclusiones preliminares sobre mecanismos de sedimentación por floculación, como así también sobre procesos de resuspensión y desplazamiento de sedimentos, observados dentro del mismo lago.