6,444 research outputs found
An update on the management of urinary tract infection
Urinary tract infection (UTI) is commonly encountered in general medical practice. The majority of patients have uncomplicated infections affecting the lower urinary tract, which respond readily to a short course of oral antibiotics. Life-threatening complications or long-term morbidity can occur, especially in patients with underlying medical predispositions or urological abnormalities. Further investigations are warranted in patients with severe or recurrent UTI, or when UTI occurs in 'low risk' individuals. Special investigations to look for vesicoureteric reflux and renal cortical scars should be considered in children with UTI. Screening of pregnant women for asymptomatic UTI is important in view of its propensity to involve the upper urinary tract. A 3-day course of appropriate oral antibiotics is often sufficient for the treatment of uncomplicated lower UTI in young females. A longer treatment duration of up to 7 days may be indicated in elderly subjects. The optimal duration of antibiotic therapy for upper UTI remains controversial. In addition to antibiotic prophylaxis, simple advice on prophylactic measures during activities of daily living is often beneficial to patients with recurrent UTI.published_or_final_versio
Dynamic Set Intersection
Consider the problem of maintaining a family of dynamic sets subject to
insertions, deletions, and set-intersection reporting queries: given , report every member of in any order. We show that in the word
RAM model, where is the word size, given a cap on the maximum size of
any set, we can support set intersection queries in
expected time, and updates in expected time. Using this algorithm
we can list all triangles of a graph in
expected time, where and
is the arboricity of . This improves a 30-year old triangle enumeration
algorithm of Chiba and Nishizeki running in time.
We provide an incremental data structure on that supports intersection
{\em witness} queries, where we only need to find {\em one} .
Both queries and insertions take O\paren{\sqrt \frac{N}{w/\log^2 w}} expected
time, where . Finally, we provide time/space tradeoffs for
the fully dynamic set intersection reporting problem. Using words of space,
each update costs expected time, each reporting query
costs expected time where
is the size of the output, and each witness query costs expected time.Comment: Accepted to WADS 201
Marketized private tutoring as a supplement to regular schooling: Liberal Studies and the shadow sector in Hong Kong secondary education
Around the world, increasing numbers of students receive after-school private supplementary tutoring. Such tutoring may be provided through informal channels or by companies; and it may be received one-to-one, in small groups, or in large classes. The tutoring is commonly called shadow education since its content mimics that of regular schooling. The spread of shadow education is part of a global shift of balance with increased roles for the private sector. Hong Kong is among the societies in which shadow education enrolment rates are particularly high. Much shadow education focuses on techniques for performance in external examinations, and is not consistent with the emphases stressed by teachers and the government. This paper focuses on a newly-introduced subject called Liberal Studies in which the tensions are especially visible. Although the official curriculum emphasizes creativity and critical thinking, many students have sought large-class tutoring focused on formulae for passing examinations. Interviews exposed the needs that the students felt were not being met in their schooling. The findings illustrate some of the complexities in relationships between the public and private sectors. Viewed in a wider context, the paper illuminates some of the mechanisms and effects of marketization which are increasingly evident globally.postprin
Colored Non-Crossing Euclidean Steiner Forest
Given a set of -colored points in the plane, we consider the problem of
finding trees such that each tree connects all points of one color class,
no two trees cross, and the total edge length of the trees is minimized. For
, this is the well-known Euclidean Steiner tree problem. For general ,
a -approximation algorithm is known, where is the
Steiner ratio.
We present a PTAS for , a -approximation algorithm
for , and two approximation algorithms for general~, with ratios
and
Association Patterns of Ontological Features Signify Electronic Health Records in Liver Cancer
published_or_final_versio
Strain- and Adsorption-Dependent Electronic States and Transport or Localization in Graphene
The chapter generalizes results on influence of uniaxial strain and
adsorption on the electron states and charge transport or localization in
graphene with different configurations of imperfections (point defects):
resonant (neutral) adsorbed atoms either oxygen- or hydrogen-containing
molecules or functional groups, vacancies or substitutional atoms, charged
impurity atoms or molecules, and distortions. To observe electronic properties
of graphene-admolecules system, we applied electron paramagnetic resonance
technique in a broad temperature range for graphene oxides as a good basis for
understanding the electrotransport properties of other active carbons. Applied
technique allowed observation of possible metal-insulator transition and
sorption pumping effect as well as discussion of results in relation to the
granular metal model. The electronic and transport properties are calculated
within the framework of the tight-binding model along with the Kubo-Greenwood
quantum-mechanical formalism. Depending on electron density and type of the
sites, the conductivity for correlated and ordered adsorbates is found to be
enhanced in dozens of times as compared to the cases of their random
distribution. In case of the uniaxially strained graphene, the presence of
point defects counteracts against or contributes to the band-gap opening
according to their configurations. The band-gap behaviour is found to be
nonmonotonic with strain in case of a simultaneous action of defect ordering
and zigzag deformation. The amount of localized charge carriers (spins) is
found to be correlated with the content of adsorbed centres responsible for the
formation of potential barriers and, in turn, for the localization effects.
Physical and chemical states of graphene edges, especially at a uniaxial strain
along one of them, play a crucial role in electrical transport phenomena in
graphene-based materials.Comment: 16 pages, 10 figure
Knuthian Drawings of Series-Parallel Flowcharts
Inspired by a classic paper by Knuth, we revisit the problem of drawing
flowcharts of loop-free algorithms, that is, degree-three series-parallel
digraphs. Our drawing algorithms show that it is possible to produce Knuthian
drawings of degree-three series-parallel digraphs with good aspect ratios and
small numbers of edge bends.Comment: Full versio
Anatomic variations of neurovascular structures of the ankle in relation to arthroscopic portals: a cadaveric study of Chinese subjects.
PURPOSE: To investigate anatomic variations of neurovascular structures in the ankle and the safety margin for arthroscopic portals. METHODS: 11 left and 12 right ankles from 8 female and 15 male fresh cadavers of Chinese ethnicity aged 53 to 88 (mean, 68) years were used. The ankle was standardised in a plantigrade position, zero-degree inversion, and neutral rotation. Four ankle portals, namely anteromedial (AM), anterolateral (AL), posteromedial (PM) and posterolateral (PL), were identified using 23-gauge needles. Skin and subcutaneous fat were dissected from the underlying fascia to visualise neurovascular structures. Distances were measured from: (1) the AM portal to the saphenous vein and nerve and its branches, (2) the AL portal to branches of the superficial peroneal nerves, of which the lateral one was labelled as the intermediate dorsal cutaneous branch and the medial one as the medial dorsal cutaneous branch, (3) the PM portal to the posterior tibial neurovascular bundles, and (4) the PL portal to the sural nerve. RESULTS: The distances from (1) the AM portal to branches of the great saphenous vein and nerve, and (2) the AL portal to the intermediate dorsal cutaneous branch of the superficial peroneal nerve were short and may be an anatomic hazard. Variations were significant among the cadavers in terms of distances of the portals to the neurovascular structures. CONCLUSION: In Chinese cadavers, variations of neurovascular structures are significant. Care must be taken to avoid inadvertent injury during ankle arthroscopy.published_or_final_versio
Simulation of the control method for the adaptive front lighting system
Author name used in this publication: K. W. E. ChengAuthor name used in this publication: S. L. HoVersion of RecordPublishe
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