405 research outputs found
Severe Hypocalcemia due to Vitamin D Deficiency after Extended Roux-en-Y Gastric Bypass
Vitamin D deficiency is a well-known comorbidity of obesity that can be exacerbated after bariatric surgery and can predispose the patient for hypocalcemia. Vitamin D and calcium doses to prevent and treat vitamin D deficiency after weight loss surgery are not well defined. We describe a patient who developed severe hypocalcemia due to vitamin D deficiency 5 years after an extended Roux-en-Y gastric bypass for a type II obesity. No precipitating factors were present and malabsorption induced by the bypass was considered to be the main causative factor. High doses of vitamin D and calcium were needed to reach and maintain normal calcium and vitamin D concentrations. This case emphasises the importance of routine screening for vitamin D deficiency in obese individuals and reflects that while consensus does not exist regarding optimal dosage, vitamin D replacement should be tittered based on calcidiol levels
Hemangiosarcoma esplénico con metástasis óseas : descripción de un caso y revisión de diversos aspectos clínicos
Se diagnosticó un caso de metástasis ósea de un hemangiosarcoma esplénico subclínico, produciendo una cojera severa y continuada. El tumor produjo una fractura patológica en el húmero proximal, haciéndose intraarticular e invadiendo la membrana sinovial de la articulación escápulo-humeral. La importancia de la artrocentesis y análisis del líquido sinovial como técnicas diagnósticas auxiliares en la investigación de patologías articulares y periarticulares es puesta de manifiesto en este caso. Asimismo, se hace una revisión de diversos aspectos clínicos del hemangiosarcoma canino.A case of osseous metastasis from an asymptomatic splenic haemangiosarcoma, which produced asevere and continous lameness, was diagnosed. The tumour produced a pathological fracture in the proximal humerus and invaded the synovial membrane of the shoulder joint. The value of arthrocentesis and synovial fluid analysis as auxiliary diagnostic techniques in the investigation of articular and periarticular pathologies is stressed. Furthermore, an overview of several clinical aspects of the canine haemangiosarcoma is discussed
Sarcoma sinovial en el perro : 2 casos clínicos
Dos casos de sarcoma sinovial fueron diagnosticados en dos Rottweiler mediante biopsias sinoviales. Se describen los signos clínicos y radiográficos, así como las características histopatológicas del tumor y del líquido sinovial.Two cases of synovial sarcoma were diagnosed in two Rottweilers on the basis of synovial biopsies. Clinical and radiographic signs are described, along with histopathologic features of the tumour and synovial fluid
Electrochemical detection of Toxocara canis excretory-secretory antigens in children from rural communities in Esmeraldas Province, Ecuador: association between active infection and high eosinophilia.
BACKGROUND: The diagnosis of active Toxocara canis infections in humans is challenging. Larval stages of T. canis do not replicate in human tissues and disease may result from infection with a single T. canis larva. Recently, we developed a nanobody-based electrochemical magnetosensor assay with superior sensitivity to detect T. canis excretory-secretory (TES) antigens. Here, we evaluate the performance of the assay in children from an Ecuadorian birth cohort that followed children to five years of age. METHODS: Samples were selected based on the presence of peripheral blood eosinophilia and relative eosinophil counts. The samples were analyzed by the nanobody-based electrochemical magnetosensor assay, which utilizes a bivalent biotinylated nanobody as capturing agent on the surface of streptavidin pre-coated paramagnetic beads. Detection was performed by a different nanobody chemically labelled with horseradish peroxidase. RESULTS: Of 87 samples tested, 33 (38%) scored positive for TES antigen recognition by the electrochemical magnetosensor assay. The average concentration of TES antigen in serum was 2.1 ng/ml (SD = 1.1). The positive result in the electrochemical assay was associated with eosinophilia > 19% (P = 0.001). Parasitological data were available for 57 samples. There was no significant association between positivity by the electrochemical assay and the presence of other soil-transmitted helminth infections. CONCLUSIONS: Our nanobody-based electrochemical assay provides highly sensitive quantification of TES antigens in serum and has potential as a valuable tool for the diagnosis of active human toxocariasis
Sub-nanoscale atom-by-atom crafting of skyrmion-defect interaction profiles
Magnetic skyrmions are prime candidates as information carriers for
spintronic devices due to their topological nature and nanometric size.
However, unavoidable inhomogeneities inherent to any material leads to pinning
or repulsion of skyrmions that, in analogy to biology concepts, define the
phenotype of the skyrmion-defect interaction, generating complexity in their
motion and challenging their application as future bits of information. Here,
we demonstrate that atom-by-atom manufacturing of multi-atomic defects, being
antiferromagnetic or ferromagnetic, permits the breeding of their energy
profiles, for which we build schematically a Punnet-square. As established from
first-principles for skyrmions generated in PdFe bilayer on Ir(111) surface,
the resulting interaction phenotype is rich. It can be opposite to the original
one and eventually be of dual pinning-repulsive nature yielding energy
landscapes hosting multi-domains. This is dictated by the stacking site,
geometry, size and chemical nature of the adsorbed defects, which control the
involved magnetic interactions. This work provides new insights towards the
development of disruptive device architectures incorporating defects into their
design aiming to control and guide skyrmions.Comment: 32 pages, 7 figure
Zitterbewegung, chirality, and minimal conductivity in graphene
It has been recently demonstrated experimentally that graphene, or
single-layer carbon, is a gapless semiconductor with massless Dirac energy
spectrum. A finite conductivity per channel of order of in the limit
of zero temperature and zero charge carrier density is one of the striking
features of this system. Here we analyze this peculiarity based on the Kubo and
Landauer formulas. The appearance of a finite conductivity without scattering
is shown to be a characteristic property of Dirac chiral fermions in two
dimensions.Comment: final version; 4 pages, 1 eps figur
Application of embedded accident prevention system for infant crawling stage in intelligent textiles
Infant crawling is a method to discover and learn its motor, cognitive, social and emotional functions. Therefore, infants face different risks, such as falls, burns and personal injuries. The most common is that the family is the place where the main event occurs. Therefore, the focus of this research is to develop the embedded system inside the intelligent textile to realize the early warning and prevention of accidents. The system is located in a clothing harness with a crawling knee pad connection including a magnetic sensor. These devices are responsible for detecting security tapes previously placed in the most dangerous location in the home. Therefore, the system gives an alarm with a response time of 7.6 seconds after activation
Analysis of quantum conductance of carbon nanotube junctions by the effective mass approximation
The electron transport through the nanotube junctions which connect the
different metallic nanotubes by a pair of a pentagonal defect and a heptagonal
defect is investigated by Landauer's formula and the effective mass
approximation. From our previous calculations based on the tight binding model,
it has been known that the conductance is determined almost only by two
parameters,i.e., the energy in the unit of the onset energy of more than two
channels and the ratio of the radii of the two nanotubes. The conductance is
calculated again by the effective mass theory in this paper and a simple
analytical form of the conductance is obtained considering a special boundary
conditions of the envelop wavefunctions. The two scaling parameters appear
naturally in this treatment. The results by this formula coincide fairly well
with those of the tight binding model.
The physical origin of the scaling law is clarified by this approach.Comment: RevTe
Prediction equations of skinfold in children of primary school
El objetivo de este trabajo es crear ecuaciones que estimen las medidas de los pliegues cutáneos para escolares de 6 a 13 años de edad. Como resultado se obtuvieron catorce ecuaciones que estiman algunos pliegues cutáneos. Las ecuaciones se validaron con muestras aleatorias de 479 niñas y 541 niños del estado de Puebla y otras 2 muestras aleatorias del estado de Veracruz con 155 niñas y 146 niños respectivamente; las mediciones directas se realizaron con la metodología y unidades ISAK (International Society for the Advancement of Kinanthropometry)The aim of this paper is to create equations that predict the skinfold measures for school children 6 to 13 years old. Fourteen resulting equations were derived to estimate some measures of skinfold. The equations were validated with random samples of 479 girls and 541 boys in the state of Puebla and 2 other random samples of the state of Veracruz with 155 girls and 146 boys respectively; direct measurements were performed with the methodology and units ISAK (International Society for the Advancement of Kinanthropometr
Band structures of periodic carbon nanotube junctions and their symmetries analyzed by the effective mass approximation
The band structures of the periodic nanotube junctions are investigated by
the effective mass theory and the tight binding model.
The periodic junctions are constructed by introducing pairs of a pentagonal
defect and a heptagonal defect periodically in the carbon nanotube.
We treat the periodic junctions whose unit cell is composed by two kinds of
metallic nanotubes with almost same radii, the ratio of which is between 0.7
and 1 .
The discussed energy region is near the undoped Fermi level where the channel
number is kept to two, so there are two bands.
The energy bands are expressed with closed analytical forms by the effective
mass theory with some assumptions, and they coincide well with the numerical
results by the tight binding model. Differences between the two methods are
also discussed. Origin of correspondence between the band structures and the
phason pattern discussed in Phys. Rev. B {\bf 53}, 2114, is clarified. The
width of the gap and the band are in inverse proportion to the length of the
unit cell, which is the sum of the lengths measured along the tube axis in each
tube part and along 'radial' direction in the junction part. The degeneracy and
repulsion between the two bands are determined only from symmetries.Comment: RevTeX, gif fil
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