377 research outputs found
Quantitative isoperimetric inequalities in H^n
In the Heisenberg group H^n, we prove quantitative isoperimetric inequalities
for Pansu's spheres, that are known to be isoperimetric under various
assumptions. The inequalities are shown for suitably restricted classes of
competing sets and the proof relies on the construction of sub-calibrations
The isoperimetric problem for regular and crystalline norms in
We study the isoperimetric problem for anisotropic left-invariant perimeter
measures on , endowed with the Heisenberg group structure. The
perimeter is associated with a left-invariant norm on the horizontal
distribution. We first prove a representation formula for the -perimeter
of regular sets and, assuming some regularity on and on its dual norm
, we deduce a foliation property by sub-Finsler geodesics of -smooth surfaces with constant -curvature. We then prove that the
characteristic set of -smooth surfaces that are locally extremal
for the isoperimetric problem is made of isolated points and horizontal curves
satisfying a suitable differential equation. Based on such a characterization,
we characterize -smooth -isoperimetric sets as the
sub-Finsler analogue of Pansu's bubbles. We also show, under suitable
regularity properties on , that such sub-Finsler candidate isoperimetric
sets are indeed -smooth. By an approximation procedure, we finally
prove a conditional minimality property for the candidate solutions in the
general case (including the case where is crystalline)
Anatomical variations in the human sinuatrial nodal artery
OBJECTIVE: To analyze the anatomical variations of sinuatrial nodal branch(es) of the coronary artery mainly regarding their number; a recent report from Japan claims the presence of 2 branches in up to 50% of cases, an occurrence that would permit adequate flow compensation in case of occlusion or section of 1 of these branches. METHODS: The sinuatrial nodal branch(es) of 50 human hearts fixed in formol solution were dissected with the aid of a Normo Health 3.0 degree visor magnifying lens, measured, and classified as to the origin, route, and number of branches. RESULTS: In 94% (n = 47) of cases, a single sinuatrial nodal branch was found. classified: (A) two right side types, R1 (in 46% of cases, n = 23), situated medial to the right auricle and R2 (in 4% of cases, n = 2), situated on the posterior surface of the right atrium; (B) three left side types, L1 (in 24% of cases, n = 12), situated medial to the left auricle, L2 (in 16% of cases, n = 8), situated posterior to the left auricle, and L3 (in 4% of cases, n = 2), situated on the posterior surface of the left atrium. Except for R2, each type was subdivided into 'a' or 'b' types, according to whether the sinuatrial nodal branch(es) occurred in a clockwise or counterclockwise orientation around the base of the superior cava vena. In 4% of cases (n = 2), 2 sinuatrial nodal branch(es) were observed with 1 branch originating from each of the coronary arteries. In 1 case (2%), 3 sinuatrial nodal branch(es) were found, 2 from the right coronary artery and the third probably from the bronchial branch of the thoracic aorta. In 30% of the cases, the sinuatrial nodal branch(es) formed a ring around the base of the superior cava vena. In all cases, the sinuatrial nodal branch(es) supplied collateral branches to the atrium and/or the auricle of the same side as its origin and/or to the opposite side. CONCLUSION: The low frequency of 2 sinuatrial nodal branch(es) in Brazilian individuals, compared to the higher frequency found among the Japanese, is probably due to a variation associated with ethnic group origin.OBJETIVO: Analisar as variações anatômicas do ramo do nó sinoatrial, principalmente quanto ao número, visto que a escola japonesa relatou a presença de dois ramos em até 50% dos casos, fato que permitiria a compensação, em caso de oclusão ou secção de um dos ramos. MÉTODOS: O ramo do nó sinoatrial foi dissecado com o auxílio de lente de aumento com pala Normo Health, de 3,0 graus, em 50 corações fixados em solução de formol. RESULTADOS: Em 94% dos casos, havia um ramo do nó sinoatrial, classificado em dois tipos do lado direito: D1 (46%) - ramo do nó sinoatrial situado medialmente à aurícula direita; D2 (4%) - ramo do nó sinoatrial na face posterior do átrio direito; e três tipos do lado esquerdo: E1 (24%) - ramo do nó sinoatrial medial à aurícula esquerda; E2 (16%) - posterior à aurícula esquerda; E3 (4%) - na face posterior do átrio esquerdo. Cada tipo, exceto D2, era subdividido em a ou b, conforme o sentido do RNSA fosse, respectivamente horário ou anti-horário ao redor da base da veia cava superior. Em 4% dos casos, havia dois ramos do nó sinoatrial, originados de ambas as artérias coronárias. Em 2% dos casos, havia três ramos do nó sinoatrial originados, dois da artéria coronária direita e o terceiro, provavelmente de artéria brônquica. Em 30% dos casos, o ramo do nó sinoatrial formava um anel ao redor da base da veia cava superior. Em todos os casos, o ramo do nó sinoatrial forneceu ramos colaterais para o átrio e/ou a aurícula do mesmo lado e/ou do lado oposto à sua origem. CONCLUSÃO: A baixa freqüência de dois ramos do nó sinoatrial em indivíduos brasileiros, comparada à alta encontrada em japoneses, provavelmente seja variação associada com as diferentes origens étnicas
DAS: a data management system for instrument tests and operations
The Data Access System (DAS) is a metadata and data management software
system, providing a reusable solution for the storage of data acquired both
from telescopes and auxiliary data sources during the instrument development
phases and operations. It is part of the Customizable Instrument WorkStation
system (CIWS-FW), a framework for the storage, processing and quick-look at the
data acquired from scientific instruments. The DAS provides a data access layer
mainly targeted to software applications: quick-look displays, pre-processing
pipelines and scientific workflows. It is logically organized in three main
components: an intuitive and compact Data Definition Language (DAS DDL) in XML
format, aimed for user-defined data types; an Application Programming Interface
(DAS API), automatically adding classes and methods supporting the DDL data
types, and providing an object-oriented query language; a data management
component, which maps the metadata of the DDL data types in a relational Data
Base Management System (DBMS), and stores the data in a shared (network) file
system. With the DAS DDL, developers define the data model for a particular
project, specifying for each data type the metadata attributes, the data format
and layout (if applicable), and named references to related or aggregated data
types. Together with the DDL user-defined data types, the DAS API acts as the
only interface to store, query and retrieve the metadata and data in the DAS
system, providing both an abstract interface and a data model specific one in
C, C++ and Python. The mapping of metadata in the back-end database is
automatic and supports several relational DBMSs, including MySQL, Oracle and
PostgreSQL.Comment: Accepted for pubblication on ADASS Conference Serie
Pituitary hyperplasia secondary to acquired hypothyroidism: case report
<p>Abstract</p> <p>Objective and Importance</p> <p>despite recent progress in imaging, it is still difficult to distinguish between pituitary adenoma and hyperplasia, even using Magnetic Resonance Imaging (MRI) with gadolinium injection. We describe an example of reactive pituitary hyperplasia from primary hypothyroidism that mimicked a pituitary macroadenoma in a child.</p> <p>Clinical Presentation</p> <p>a 10 year old boy presented with headache and statural growth arrest. MRI revealed an intrasellar and suprasellar pituitary mass. Endocrine evaluation revealed primary hypothyroidism.</p> <p>Intervention</p> <p>the patient was started on levothyroxine with resolution of the mass effect.</p> <p>Conclusion</p> <p>primary hypothyroidism should be considered in the differential diagnosis of solid mass lesions of the pituitary gland. Examination of thyroid function in patients with sellar and suprasellar masses revealed by MRI may avoid unnecessary operations which can cause irreversible complications.</p
CIWS-FW: a Customizable InstrumentWorkstation Software Framework for instrument-independent data handling
The CIWS-FW is aimed at providing a common and standard solution for the
storage, processing and quick look at the data acquired from scientific
instruments for astrophysics. The target system is the instrument workstation
either in the context of the Electrical Ground Support Equipment for
space-borne experiments, or in the context of the data acquisition system for
instrumentation. The CIWS-FW core includes software developed by team members
for previous experiments and provides new components and tools that improve the
software reusability, configurability and extensibility attributes. The CIWS-FW
mainly consists of two packages: the data processing system and the data access
system. The former provides the software components and libraries to support
the data acquisition, transformation, display and storage in near real time of
either a data packet stream and/or a sequence of data files generated by the
instrument. The latter is a meta-data and data management system, providing a
reusable solution for the archiving and retrieval of the acquired data. A
built-in operator GUI allows to control and configure the IW. In addition, the
framework provides mechanisms for system error and logging handling. A web
portal provides the access to the CIWS-FW documentation, software repository
and bug tracking tools for CIWS-FW developers. We will describe the CIWS-FW
architecture and summarize the project status.Comment: Accepted for pubblication on ADASS Conference Serie
Mine Closure in Iberoamerica (Module V, Economy and Finances)
Dina Franceschi is a contributing author, Improving Environmental Compliance in Mine Closure: The Case for a System of Performance Bonds , p. 207-218.
Book description: This book brings to the interested public the discussions and propositions delivered during the First Iberoamerican Seminar on Mine Closure held in La Rabida, at the monastery where Colon lived upon his return to Spain, after reaching the American Continent.-- Foreword.https://digitalcommons.fairfield.edu/economics-books/1005/thumbnail.jp
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