293 research outputs found
Herstel van de fascia transversalis bij directe of indirecte liesbreuken
De chirurgische behandeling van liesbreuken geniet nog steeds grote belangstelling,
getuige de ongeveer zeventig publicaties die per jaar over dit onderwerp
verschijnen.
In onze moderne tijd met de grote vooruitgang in de hartchirurgie en de
orgaantransplantaties lijkt het onbegrijpelijk, dat aan dit onderwerp nog zoveel
aandacht wordt besteed. Begrijpelijker wordt dit echter, wanneer men zich
realiseert dat in Nederland ongeveer 25.000 liesbreukoperaties per jaar worden
verricht (Van de Wetering 1960) en dat het percentage recidieven in de literatuur
varieert van 2,5 tot 30, waarbij opvalt dat de lagere percentages meestal worden
verkregen bij nacontroles, die zijn verricht per circulaire.
Ontevredenheid over de bereikte resultaten verklaart de voortdurende belangstelling
voor dit onderwerp.
Reeds in 1921 stelde Pitzman: "The size and endlessness of the stream of
inguinal herniotomy technique raises the strong suspicion that sarnething is fundamenrally
wrong".
De stroom van nieuwe technieken of modificaties op oude technieken is
echter blijven aanhouden.
De laatste twee decennia is er belangrijke vooruitgang geboekt in het praktisch
gebruik van de verworven anatomische kennis van het liesgebied, zodat
sommige eerder geaccepteerde orthodoxe anatomische concepten moesten worden
herzien, evenals sommige details van erkende technische procedures voortdurend
moesten worden gemodificeerd
Actors that Unify Threads and Events
There is an impedance mismatch between message-passing concurrency and virtual machines, such as the JVM. VMs usually map their threads to heavyweight OS processes. Without a lightweight process abstraction, users are often forced to write parts of concurrent applications in an event-driven style which obscures control flow, and increases the burden on the programmer. In this paper we show how thread-based and event-based programming can be unified under a single actor abstraction. Using advanced abstraction mechanisms of the Scala programming language, we implemented our approach on unmodified JVMs. Our programming model integrates well with the threading model of the underlying VM
Sub-millimeter Tests of the Gravitational Inverse-square Law
Motivated by a variety of theories that predict new effects, we tested the
gravitational 1/r^2 law at separations between 10.77 mm and 137 microns using
two different 10-fold azimuthally symmetric torsion pendulums and rotating
10-fold symmetric attractors. Our work improves upon other experiments by up to
a factor of about 100. We found no deviation from Newtonian physics at the 95%
confidence level and interpret these results as constraints on extensions of
the Standard Model that predict Yukawa or power-law forces. We set a constraint
on the largest single extra dimension (assuming toroidal compactification and
that one extra dimension is significantly larger than all the others) of R <=
160 microns, and on two equal-sized large extra dimensions of R <= 130 microns.
Yukawa interactions with |alpha| >= 1 are ruled out at 95% confidence for
lambda >= 197 microns. Extra-dimensions scenarios stabilized by radions are
restricted to unification masses M >= 3.0 TeV/c^2, regardless of the number of
large extra dimensions. We also provide new constraints on power-law potentials
V(r)\propto r^{-k} with k between 2 and 5 and on the gamma_5 couplings of
pseudoscalars with m <= 10 meV/c^2.Comment: 34 pages, 38 figure
Improving biosecurity: A necessity for aquaculture sustainability
The implementation of biosecurity measures is vital to the future development of aquaculture, if the culture of aquatic species is to make it possible to feed the global human population by 2030. Biosecurity includes control of the spread of aquatic plant and animal diseases and invasive pests, and the production of products that are safe to eat. For controls on diseases and invasive pests, it is necessary to implement programmes that involve all regional countries. Lessons from measures implemented in Asia need to be expanded/upscaled in Latin America, Africa and other emerging aquaculture regions. Such development will make countries more self sufficient and will feed local populations.
Globally, there is good evidence that aquatic animal diseases and invasive animal and plant pests are being spread by hull fouling and ballast water in shipping, and serious aquatic animal diseases by the international trade in ornamental fish. While there has been a growing awareness of the danger of ballast water transfer, hull fouling remains a serious problem. It is widely recognized that ornamental fish present a disease risk, but individual countries have tried to address this alone, and there has not been an international effort to control the trade.
Developments in genetics and molecular biology hold great potential for disease control, either by breeding for disease resistance, or by the use of rapid, specific, culture site testing. Currently, there is no evidence that the use of antibiotics in aquaculture poses a threat to human health or that antibiotic-resistant strains have developed; however, the future use of genetically modified aquatic organisms (GMOs) may negate the need for chemotherapy. Cultured aquatic organisms, selected for disease resistance or rapid growth, are likely to become more acceptable, and probably necessary, to feed the rapidly growing global population.
Most global aquaculture occurs in developing Asian countries, in which aquaculture products can harbor zoonotic parasites, and there is a need to treat such products to negate the threat of parasitic zoonoses and permit international export. Climate change is likely to be a major influence on aquaculture in the future, with impacts on coastal aquaculture through increased sea levels affecting coastlines, and acidification. To feed the growing global population, it will be necessary to culture new species, for which research on diseases and invasiveness will be necessary to acquire the information necessary to implement biosecurity measures
Optical symmetries and anisotropic transport in high-Tc superconductors
A simple symmetry analysis of in-plane and out-of-plane transport in a family
of high temperature superconductors is presented. It is shown that generalized
scaling relations exist between the low frequency electronic Raman response and
the low frequency in-plane and out-of-plane conductivities in both the normal
and superconducting states of the cuprates. Specifically, for both the normal
and superconducting state, the temperature dependence of the low frequency
Raman slope scales with the axis conductivity, while the
Raman slope scales with the in-plane conductivity. Comparison with experiments
in the normal state of Bi-2212 and Y-123 imply that the nodal transport is
largely doping independent and metallic, while transport near the BZ axes is
governed by a quantum critical point near doping holes per
CuO plaquette. Important differences for La-214 are discussed. It is also
shown that the axis conductivity rise for is a consequence of
partial conservation of in-plane momentum for out-of-plane transport.Comment: 16 pages, 8 Figures (3 pages added, new discussion on pseudogap and
charge ordering in La214
Comparison of pharmacopeial statistical methods applied in microbiological assay for antibiotics potency determination using parallel lines and three-dose level
Pharmaceutical equivalence studies, useful for checking the interchangeability of generic medicines and their respective innovator medicines, have been carried out in Brazil since 1999, as a consequence of the establishment of the generic medicine policy. For medicines containing antibiotics, microbiological assays are often the most appropriate method. However, the statistical methods applied in these assays are not widely known due to the difficult access to official codes and/or little knowledge of the statistical tools of analysis. Thus, the aim of this work was to compare the statistical methods for determining the potency of antibiotics through the cylinder-plate method using parallel lines and a three-dose level model, as described in the Brazilian Pharmacopeia (4th edition, 1988), British Pharmacopoeia 2011, European Pharmacopoeia (7th edition), The International Pharmacopoeia (4th edition), and United States Pharmacopeia (34th edition). The assay is illustrated with the antibiotic ofloxacin, and details on orthogonal coefficients, normality test, homogeneity of variance test, and detection of outliers are discussed. The calculations obtained by statistical analyses from different pharmacopeias lead to the same final interpretation. In practice, with the availability of alternative pharmacopeial methods, the analyst can choose the most appropriate statistical calculation to be used.Os estudos de equivalência farmacêutica, úteis na verificação da intercambialidade entre os medicamentos genéricos e respectivos medicamentos de referência, têm sido realizados no Brasil desde 1999, como consequência do estabelecimento da política de medicamentos genéricos. Para medicamentos contendo antibióticos, os ensaios microbiológicos são, muitas vezes, o método mais adequado. Entretanto, os métodos estatísticos aplicados nesses ensaios não são amplamente conhecidos devido à dificuldade de acesso aos compêndios oficiais e/ou pouca compreensão das ferramentas estatísticas de análises. Portanto, o objetivo desse trabalho foi comparar os métodos estatísticos para determinação de potência de antibióticos pelo delineamento por retas paralelas e três níveis de doses, descritos nas farmacopeias Brasileira 4. ed. (1988), Britânica 2011, Europeia 7. ed., Internacional 4. ed. e na Farmacopeia dos Estados Unidos 34. ed. (2011). O ensaio é exemplificado com o antibiótico ofloxacino e detalhes sobre coeficientes ortogonais, teste de normalidade, teste de homogeneidade de variância e detecção de outliers são discutidos. Os cálculos obtidos pelas análises estatísticas segundo as diferentes farmacopeias resultaram na mesma interpretação final. Na prática, métodos farmacopéicos alternativos permitem ao analista a escolha do cálculo estatístico mais apropriado a ser utilizado
Low Q^2 Jet Production at HERA and Virtual Photon Structure
The transition between photoproduction and deep-inelastic scattering is
investigated in jet production at the HERA ep collider, using data collected by
the H1 experiment. Measurements of the differential inclusive jet
cross-sections dsigep/dEt* and dsigmep/deta*, where Et* and eta* are the
transverse energy and the pseudorapidity of the jets in the virtual
photon-proton centre of mass frame, are presented for 0 < Q2 < 49 GeV2 and 0.3
< y < 0.6. The interpretation of the results in terms of the structure of the
virtual photon is discussed. The data are best described by QCD calculations
which include a partonic structure of the virtual photon that evolves with Q2.Comment: 20 pages, 5 Figure
Hadron Production in Diffractive Deep-Inelastic Scattering
Characteristics of hadron production in diffractive deep-inelastic
positron-proton scattering are studied using data collected in 1994 by the H1
experiment at HERA. The following distributions are measured in the
centre-of-mass frame of the photon dissociation system: the hadronic energy
flow, the Feynman-x (x_F) variable for charged particles, the squared
transverse momentum of charged particles (p_T^{*2}), and the mean p_T^{*2} as a
function of x_F. These distributions are compared with results in the gamma^* p
centre-of-mass frame from inclusive deep-inelastic scattering in the
fixed-target experiment EMC, and also with the predictions of several Monte
Carlo calculations. The data are consistent with a picture in which the
partonic structure of the diffractive exchange is dominated at low Q^2 by hard
gluons.Comment: 16 pages, 6 figures, submitted to Phys. Lett.
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