Predicting soil water content at - 33 kPa by pedotransfer functions in stoniness 1 soils in northeast Venezuela.

Soil water content is a key property in the study of water available for plants, infiltration, drainage, hydraulic conductivity, irrigation, plant water stress and solute movement. However, its measurement consumes time and, in the case of stony soils, the presence of stones difficult to determinate the water content. An alternative is the use of pedotransfer functions (PTFs), as models to predict these properties from readily available data. The present work shows a comparison of different widely used PTFs to estimate water content at-33 kPa (WR-33kPa) in high stoniness soils. The work was carried out in the Caramacate River, an area of high interest because the frequent landslides worsen the quality of drinking water. The performance of all evaluated PTFs was compared with a PTF generated for the study area. Results showed that the Urach's PTF presented the best performance in relation to the others and could be used to estimate WR-33kPa in soils of Caramacate River basin. The calculated PTFs had a R2 of 0.65. This was slightly higher than the R2 of the Urach's PTF. The inclusion of the rock fragment volume could have the better results. The weak performance of the other PTFs could be related to the fact that the mountain soils of the basin are rich in 2:1 clay and high stoniness, which were not used as independent variables for PTFs to estimate the WR-33kPa.

Landslides susceptibility change over time according to terrain conditions in a mountain area of the tropic region.

Susceptibility to landslides in mountain areas results from the interaction of various factors related to relief formation and soil development. The assessment of landslide susceptibility has generally taken into account individual events, or it has been aimed at establishing relationships between landslide-inventory maps and maps of environmental factors, without considering that such relationships can change in space and time. In this work, temporal and space changes in landslides were analysed in six different combinations of date and geomorphological conditions, including two different geological units, in a mountainous area in the north-centre of Venezuela, in northern South America. Landslide inventories from different years were compared with a number of environmental factors by means of logistic regression analysis. The resulting equations predicted landslide susceptibility from a range of geomorphometric parameters and a vegetation index, with diverse accuracy, in the study area. The variation of the obtained models and their prediction accuracy between geological units and dates suggests that the complexity of the landslide processes and their explanatory factors changed over space and time in the studied area. This calls into question the use of a single model to evaluate landslide susceptibility over large regions.

Robotic assessment of neuromuscular characteristics using musculoskeletal models: A pilot study.

OBJECTIVE: Non-invasive neuromuscular characterization aims to provide greater insight into the effectiveness of existing and emerging rehabilitation therapies by quantifying neuromuscular characteristics relating to force production, muscle viscoelasticity and voluntary neural activation. In this paper, we propose a novel approach to evaluate neuromuscular characteristics, such as muscle fiber stiffness and viscosity, by combining robotic and HD-sEMG measurements with computational musculoskeletal modeling. This pilot study investigates the efficacy of this approach on a healthy population and provides new insight on potential limitations of conventional musculoskeletal models for this application. METHODS: Subject-specific neuromuscular characteristics of the biceps and triceps brachii were evaluated using robot-measured kinetics, kinematics and EMG activity as inputs to a musculoskeletal model. RESULTS: Repeatability experiments in five participants revealed large variability within each subjects evaluated characteristics, with almost all experiencing variation greater than 50% of full scale when repeating the same task. CONCLUSION: The use of robotics and HD-sEMG, in conjunction with musculoskeletal modeling, to quantify neuromuscular characteristics has been explored. Despite the ability to predict joint kinematics with relatively high accuracy, parameter characterization was inconsistent i.e. many parameter combinations gave rise to minimal kinematic error. SIGNIFICANCE: The proposed technique is a novel approach for in vivo neuromuscular characterization and is a step towards the realization of objective in-home robot-assisted rehabilitation. Importantly, the results have confirmed the technical (robot and HD-sEMG) feasibility while highlighting the need to develop new musculoskeletal models and optimization techniques capable of achieving consistent results across a range of dynamic tasks.

Cerebral sponginess and GM3 gangliosidosis; ultrastructure and probable pathogenesis.

Extensive multifocal vacuolation of the cerebral hemispheres, brain stem, cerebellum, optic nerves and spinal cord were demonstrated in a 3 1/2 month-old infant. This co-existed with marked increases in cerebral and hepatic ganglioside GM3 (hematoside), absence of its higher homologues (GM1 and GM2) and absence of tissue N-acetylgalactosaminyl transferase. Ultrastructurally, there are major abnormalities in myelin and astroglia. The absence of identifiable "storage" material is believed to correlate with an enzymatic defect involved in ganglioside anabolism. A familial occurrence of this disorder is strongly suggested by the clinical history.

Unusual demyelinating disease. A form of diffuse-disseminated sclerosis.

A young man, in good health until the age of 22, developed progressive personality changes, lethargy, motor diffuculities, urinary bladder dysfunction, and convulsions. Spinal fluid abnormalities included monocytic pleocytosis and selective increase of gamma globulins. The clinical features and the structural lesions in the central nervous system are reminiscent of disseminated-diffuse sclerosis. Oligodendrocytes appeared normal in number and showed nonspecific abnormalities. Comparison of the structural lesions found in this case with those described in seven reports of demyelination indicates that the separation of this syndrome, as a distinct entity, may not be justified. We suggest that such cases be classified as myelinoclastic disorders, in the same category with multiple sclerosis and its variants.

Multiple pulmonary leiomyomatous hamartomas in women.

A rare case of multiple pulmonary leiomyomatous hamartomas is described and seven previously reported cases are reviewed. The pathological and clinical features of this lesion, which is benign and occurs in middle-aged women, are unique; a conservative approach following the establishment of diagnosis is recommended.

Thoracopulmonary hypogenesis with systemic artery-pulmonary vessel fistulae: report of a case.

A patient seen with recurrent hemoptysis was found to have large systemic artery-pulmonary vessel fistulae. Associated anomalies were unique, and included hypogenetic left thorax, hypoplastic unilobar left lung, and dextrocardia. Left pneumonectomy was curative.

A case of laboratory acquired Leishmania donovani infection; evidence for primary lymphatic dissemination.

We report the case of a laboratory worker who received close medical follow-up after accidently inoculating her hand with a needle containing a Humera strain of Leishmania donovani amastigotes. She developed a leishmanoma and histologic evidence of local lymphatic dissemination before being treated. The spectrum of disease caused by L. donovani is discussed.

Sebaceous cell carcinoma of the parotid gland.

Sebaceous cell carcinoma of the parotid gland is a rare lesion. A review of the English literature reveals nine previously reported cases. Two cases are presented in which the tumor was originally diagnosed as mucoepidermoid carcinoma. Aggressive treatment of the recurrence, which was subsequently recognized as sebaceous cell carcinoma has resulted in apparent cure. Histologic features and possible histogenesis are discussed.

Lumbosacral spinal intradural extramedullary paciniomyolipoma: magnetic resonance imaging, computed tomography, and pathology findings.

This report describes a paciniomyolipoma as an intradural tumor of the lumbar spinal cord composed of adipose tissue, striated skeletal muscle, and pacinian corpuscles. Simple lipomas, myolipomas, and other variant lipomas of the spinal cord have been described in the literature; to the authors' knowledge, however, this is the first report of this unusual and unique lipoma.

Extramedullary plasmacytoma of the orbit: case report with results of immunocytochemical studies.

Orbital involvement as the initial manifestation of primary extramedullary plasmacytoma is rare. The case presented in this article illustrates several interesting aspects of the disease. The neoplastic process involved monoclonal B-lymphocytes that produced IgG-lambda chains.

Intoxicación por setas: síndrome orellánico / Mushroom poisoning: Orellanus syndrome

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Human Herpes simplex encephalitis (cellular events).

Electron microscopic demonstration of herpes viral particles in cerebral tissues obtained at autopsy was easily accomplished. Analysis of the structural abnormalities in this case offers support for the proposed mechanisms of cellular injury in herpes simplex encephalitis. Interference with synthesis of nucleic acids and glycoproteins which has been suggested by in vitro studies correlates well with the structural abnormalities of endoplasmic reticulum cisternae and changes in nuclear membranes, described in the case reported herein.

Histoplasma capsulatum in vessels of the choroid.

In a 3-year-old boy disseminated histoplasmosis was recognized from a liver biopsy. The patient died shortly afterwards and had foci of the disease in liver, spleen, and kidneys. Large numbers of yeast cells of Histoplasma capsulatum were found within histiocytes in other organs including the eye. This rare finding is remarkable in view of the search for Histoplasma capsulatum in the syndrome known as "so-called histoplasmosis of the choroid."

Cardiac tamponade as a presentation of extracardiac malignancy.

Three cases of adenocarcinoma of the lung manifesting as acute pericardial effusion with tamponade are presented and the medical literature concerning this unusual manifestation of extracardiac malignancy is reviewed. We have found 22 cases of carcinoma and 4 cases of sarcoma. Of the carcinomas, 14 of 19 (74%) with known primary are pulmonary and 13 of 18 (72%) with tissue diagnosis are adenocarcinomas. Daignosis was made by cytologic examination of pericardial fluid in 14 of 16 cases (87%) in which it was performed. The lymphatic drainage of the heart renders some anatomical explanations for the prevalence of carcinoma of the lung as the cause of cardiac tamponade and the discrepancy of finding tumor cells in the pericardial fluid but not in the pericardium. Patients treated with pericardiectomy with or without ancillary radio- or chemotherapy survived longer than those treated with periocardiocentesis or radio- or chemotherapy alone.

Malignant fibrous histiocytomas of the head and neck.

Fibrous histiocytomas are soft tissue neoplasms of histiocytic origin showing partial fibroblastic and histiocytic differentiation. The histopathology of these tumors and their nomenclature are discussed. A case of primary intraosseous malignant fibrous histiocytoma of the mandible is presented and added to the previously reported nine cases. One hundred and ten cases of fibrous histiocytoma are reviewed, a rapidly increasing number of reported cases in the deep tissues of the head and neck region. No definite reliable histologic criteria have been found to predict the true malignant lesions. Malignant fibrous histiocytomas show the most aggressive behavior in the head and neck region with a metastatic rate of 30-42%. Aggressive surgery remains the treatment of choice with a five year survival rate of approximately 60%, chemotherapy and radiotherapy being used as adjunctive treatment.