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Depending on whether the experiments are quasi-static or fast dynamics, the measured twin boundary velocity values range from zero to the material's sound speed. The twin boundary velocity is not yet predicted theoretically in the continuum mechanics framework. The extension of continual description is provided in the paper by means of internal variables. It is shown that a diffusional slow motion of twin boundaries can be represented using a single internal variable. The dual internal variable technique is employed for the description of the fast dynamics of twin boundaries. [ABSTRACT FROM AUTHOR]

The dynamic space charge distribution within cross‐linked polyethylene (XLPE) cable insulations is simulated in this study. To simulate charge dynamics inside the insulation, different models have been developed. Conductivity‐based models describe electronic and ionic charges. Such models are structurally simpler than bipolar charge transport models because of their macroscopic description. So far, the macroscopic description is insufficient, as it does not depict the accumulation of homocharges and heterocharges near the electrodes and the transport of charge packets. In this study, a conductivity‐based model is developed to simulate the transport of charges and the formation of homocharges and heterocharges. The conductivity model depends on the electric field and on the temperature. This model is extended by two Gaussian curves, moving from the electrodes to the counter electrodes, which features an increased conductivity in comparison to bulk conductivity. The bulk conductivity is obtained from measurements in the literature. The permittivity is modelled to be non‐constant in the vicinity of the electrodes due to e.g. interdiffusion between the bulk insulation and the semiconducting layer. A comparison between the simulation results and the reference measurements confirms the applicability of the presented approach for the description of the dynamic charge distribution in XLPE cable insulation. [ABSTRACT FROM AUTHOR]

Background: Sloths of the species Bradypus variegatus are mammals with peculiar habits, which feed mostly young leaves of 'embaúba' and occur broadly in Central and South America. This specie has the greatest occurrence in Brazilian Northeast, making it a biological model for several researches in the fields as anatomy, physiology, genetics, pathology, histology and ecology, which provide data to literature in order to benefit maintenance and preservation of these animals. This study aimed to describe unpublished data about small and large intestine anatomy of the sloth Bradypus variegatus, in order to collaborate for knowledge of its digestive processes. Materials, Methods & Results: In order to perform this present research, 10 corpses of specie Bradypus variegatus belonged to the acquis of Anatomy Division, Department of Animal Morphology and Physiology (DMFA); Federal Rural University of Pernambuco (UFRPE), with 5 males and 5 females, the study was authorized by Animal Use and Experimentation Ethic Committee license (CEUA-UFRPE), n° 034/2015. All 10 animals used had natural death, were obtained through a donation of CETAS Tangará (Centro de Triagem de Animais Silvestres - Wildlife Screening Center), and located in the city of Recife. Animals were dissected at abdominal and pelvic portion, from a median sagittal incision, followed by lateral folding of skin, muscle and withdrawal of pubis portion for exposition and description of intestines, with analysis of syntopy and measurement of these organs. A relation was observed among external holes of urinary, reproductive and digestive systems. A relation was still observed among intestines and stomach, liver, kidneys, bladder and abdominal cavity wall. Some animals had absence of sigmoid colon, ventral and dorsal descendent colon. Regarding measurement, small intestine ranged from 147.09 to 163.59 cm for males and 117.44 to 151.28 cm for females, while large intestine varied between 39.68 and 43.35 cm for males, and 33.19 and 44.47 cm for females. Urinary and reproductive systems had a same external hole at perineal portion for both gender. Whereas digestive system ended at anus as occur commonly among mammals. Discussion: Among specimens described, most had the same anatomic profile regarding the intestinal portions and syntopy performed over other abdominal cavity organs. A difference was observed on liver size, increment of 20% for females and males sampled, excluding animals that had absence of structure that were minority, once 40% of females had no ventral descending colon, 20% of males and females had no sigmoid colon, and 20% of males had no dorsal descending colon. However, some animals that had absence demonstrated increase of other adjacent structures, for example, male that had no dorsal descending colon developed the largest sigmoid colon observed among animals measured for portions of duodenum, ventral descending colon, ascending colon and dorsal descending colon. Regarding the measurement of small and large intestine, Bradypus variegatus had differences compared to other herbivores, what suggests that this fact is associated to a restricted diet, in which that animal is submitted. Because of literature shortage about digestive system of specie Bradypus variegatus and other species of wild animals in general, it still difficult to infer or plot more accurate affirmations about this subject. [ABSTRACT FROM AUTHOR]

A new macroscopic description of capillary transport of liquid and gas in porous materials is presented within the framework of multiphase continuum mechanics. It is assumed that unsaturated porous material form a macroscopic continuum composed of three constituents: gas, mobile liquid and capillary liquid, while the skeleton is rigid with an isotropic pore space structure. The capillary liquid forms a thin layer on the internal contact surface with the skeleton, is immoveable and contains the whole capillary energy. The remaining part of the liquid, surrounded by the layer of the capillary liquid and menisci, forms the constituent called mobile liquid. Both liquids exchange mass, momentum and energy in the vicinity of menisci surfaces during their motion, which is described by an additional macroscopic velocity field. A macroscopic scalar quantity is introduced, parametrizing changes of saturations, which for quasi static and stationary processes is equal to the capillary pressure. This quantity extends the dimensionality of the description of mechanical processes taking place in unsaturated porous materials. For the three fluid constituents of the medium, balance equations of mass and linear momentum and evolution equations for saturations are formulated. The constitutive relations for quantities describing mechanical processes in such a medium are proposed based on the dissipation inequality of mechanical energy for the whole system. A new approach is proposed, similar to that used in rational thermodynamics, based on entropy inequality analysis and the Lagrange multipliers method. [ABSTRACT FROM AUTHOR]

Abstract: The macroscopic design of granular filtration is based on phenomenological equations for the prediction of the overall filtration efficiency and pressure drop across the length of a typical filter. Despite the fact that a variety of empirical models have already been proposed in the past, an analytical expression for the prediction of the performance of the porous medium during filtration process is not yet broadly accepted. In the particular case of horizontal flow filtration, a non-uniform distribution of particle and cluster deposits along the main direction of flow (width of the horizontal filter) is obtained, which necessitates a three-dimensional phenomenological description. To evade the assumption of uniform deposition of particles within a certain zone, differential mass balance expressions are introduced in the present work, and filtration rates are expressed as functions of the width and the depth of the filter. Results for the filter coefficient correction factors entered in the macroscopic equations are presented for the case of horizontal flow and are compared with results from downward filtration. [Copyright &y& Elsevier]

Consideration is given to the dynamics of disturbances of a charged weakly ionized plasma on exposure to a fairly strong electric field in the presence of high velocities and disturbance gradients. Equations for macroscopic description of the plasma are constructed by the projective-kinetic method; the general expressions for correlation functions and their related nonequilibrium kinetic coefficients are obtained. With the example of the correlation density function and the diffusion coefficient of a highly nonequilibrium plasma, the asymptotics of its kinetic coefficients is considered. [ABSTRACT FROM AUTHOR]

We present the anatomical study of a horseshoe kidney found during dissection practice at the human anatomy laboratory. The specimen consisted of a renal mass joined at its lower poles by an isthmus composed of renal parenchyma. We provide a macroscopic description of renal blood supply and the excretory system. We also discuss the anatomic and embryologic importance of this anomaly. [ABSTRACT FROM AUTHOR]

Casa Montero is a mining complex located outside Madrid (Spain), dated from the Early Neolithic (c. 5400–5000 cal bc ). An area of some 4 ha has been investigated and some 4000 shafts recorded, of which 324 have been excavated. The characterization of its raw flint materials and the establishment of its diagnostic features are indispensable in the reconstruction of the distribution of the mine's products beyond the immediate site. This work reports the geological study of the mine's Miocene flint layers and their petrological characterization. Archaeological samples from the mine's shafts were classified according to macroscopic features and petrological characteristics. [ABSTRACT FROM AUTHOR]

Summary: The aim of the study was a qualitative anatomical analysis of the macroscopic features of the surface of the calcaneal tuberosity, of the architecture of its cancellous bone and histological structure of the whole region. Dry human bones and pathological dissection material 24–36h post mortem were used in the study. On the tuberosity, the variability of its surface relief and the two borders between the superior, middle and inferior facets were studied. More frequent medial declination of the inferior line, corresponding to the distal circumference of the Achilles tendon attachment, was found. Two systems of expressive condensation of cancellous bone just below the surface of the calcaneal tuberosity were described. In the histological part of the study, the distribution and different thickness of the fibrous cartilage layer covering the attachment region of Achilles tendon, the bottom of retrocalcaneal bursa and the whole surface of the calcaneal tuberosity were described. The functional and clinical relevance of results obtained are evaluated from the point of view of disciplines dealing with the pathology and surgery of the heel region. The relationships of official anatomical terms and a wide spectrum of clinical synonyms designating this region are discussed. [Copyright &y& Elsevier]

We examined whether introduction of a structured macroscopic reporting template for rectal tumour resection specimens improved the completeness and efficiency in collecting key macroscopic data elements. Fifty free text (narrative) macroscopic reports retrieved from 2012 to 2014 were compared with 50 structured macroscopic reports from 2013 to 2015, all of which were generated at John Hunter Hospital, Newcastle, NSW. The six standard macroscopic data elements examined in this study were reported in all 50 anatomical pathology reports using a structured macroscopic reporting dictation template. Free text reports demonstrated significantly impaired data collection when recording intactness of mesorectum (p<0.001), relationship to anterior peritoneal reflection (p=0.028) and distance of tumour to the non-peritonealised circumferential margin (p<0.001). The number of words used was also significantly (p<0.001) reduced using pre-formatted structured reports compared to free text reports. The introduction of a structured reporting dictation template improves data collection and may reduce the subsequent administrative burden when macroscopically evaluating rectal resections., (Copyright © 2016 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.)