2,398 research outputs found
Long-term clinical and radiographic results of acl reconstruction. Retrospective comparison between three techniques (hamstrings autograft, hamstrings autograft with extra-articular reconstruction, bone patellar tendon autograft)
Background. There is no consensus in the current literature on which surgical options render the best long-term results after ACL reconstruction in terms of clinical outcomes and development of radiographic osteoarthritis (AO).
The aim of this study is to investigate clinical and radiological results at long-term follow up after ACL reconstruction using hamstring tendons autograft (Group HT), hamstrings autograft with extra-articular reconstruction (Group HT-ER), and bone patellar tendon bone autograft (Group BPTB).
Methods. All patients were evaluated at final follow-up using Lysholm, Internation- al Knee Documentation Committee (IKDC), and Tegner scores. An arthrometric KT-1000 evaluation was also done. Comparative weight bearing radiographs were taken, including a skyline view for patellofemoral joint and analyzed according to Fair- bank, Kellgren, and IKDC classification.
Sixty patients were selected for this retrospective study, 20 for each group. The mini- mum final follow-up was 10 years for each group. All patients were male and involved in sport activities (Tegner pre-injury >7).
Results. Subjective scores improved significantly in all groups, with no significative differences between groups (P<0,05).
The number of patients classified as C or D at the IKDC objective activity score was higher in Group HT (2/20, 10%), than in Group BTB (1/20, 5%) and Group HT-E (0/20, 0%).
In term of failure-rate, there were no difference between the three groups (P<0,05). Radiologic evaluation shoved more arthritic changes in Group-BT in the patello-fem- oral joint (PMJ).
Conclusions. All the three techniques showed satisfactory results at long term follow up with no differences in term of subjective scores. Finally, there was a statistically significant higher incidence of arthritic changes in PFJ as evaluated with x-ray in the BPTP group respect to HT and HT + ER groups (p<0.05)
Genetic diversity of wild-type measles viruses: implications for global measles elimination programs.
Wild-type measles viruses have been divided into distinct genetic groups according to the nucleotide sequences of their hemagglutinin and nucleoprotein genes. Most genetic groups have worldwide distribution; however, at least two of the groups appear to have a more limited circulation. To monitor the transmission pathways of measles virus, we observed the geographic distribution of genetic groups, as well as changes in them in a particular region over time. We found evidence of interruption of indigenous transmission of measles in the United States after 1993 and identified the sources of imported virus associated with cases and outbreaks after 1993. The pattern of measles genetic groups provided a means to describe measles outbreaks and assess the extent of virus circulation in a given area. We expect that molecular epidemiologic studies will become a powerful tool for evaluating strategies to control, eliminate, and eventually eradicate measles
Urban Heat Island (UHI) risk maps as innovative tool for urban regeneration strategies. The case of Parma
For the purposes of regeneration of the consolidated city it is increasingly important
to have the knowledge of the micro-scale distribution of the vulnerability of the population to
the consequences of climate change and increasing urbanization. The work to be presented starts
with the creation of maps of the risk classification induced by the heat islands in the city of
Parma, and aims to investigate which are the most effective strategies that a Public
Administration can adopt. The maps that have been created allow to assess the risk for the fragile
population at the level of the single building. They relate the climatic datum of thermal variation
with the population residing within each building, and verify the causal relationship with the soil
sealing and with the morphology of the urban fabric. The results of the study can help to identify
the thermal hot spot, receivers of specific mitigation actions. The risk map is itself a tool to
develop multilevel actions, designed according to the peculiarities of the sites, where the possible
adaptive solutions are compared with the physical and morphological characteristics of the
places. The positive function of green infrastructures (contrast of overheating, flood mitigation,
creation of places and services with a recreational function) is acquired by research and urban
planning practice. It is equally well known the difficulty faced by Local Authorities in the
maintenance and increase of unbuilt public areas, fundamental for the connection of ecological
networks
Efficient Quantum Tensor Product Expanders and k-designs
Quantum expanders are a quantum analogue of expanders, and k-tensor product
expanders are a generalisation to graphs that randomise k correlated walkers.
Here we give an efficient construction of constant-degree, constant-gap quantum
k-tensor product expanders. The key ingredients are an efficient classical
tensor product expander and the quantum Fourier transform. Our construction
works whenever k=O(n/log n), where n is the number of qubits. An immediate
corollary of this result is an efficient construction of an approximate unitary
k-design, which is a quantum analogue of an approximate k-wise independent
function, on n qubits for any k=O(n/log n). Previously, no efficient
constructions were known for k>2, while state designs, of which unitary designs
are a generalisation, were constructed efficiently in [Ambainis, Emerson 2007].Comment: 16 pages, typo in references fixe
Catalytic electrophilic halogenation of silyl-protected and terminal alkynes: trapping gold(I) acetylides vs. a bronsted acid-promoted reaction
In the presence of a cationic gold(I) catalyst and N-halosuccinimide, both trimethylsilyl-protected and terminal alkynes are converted into alkynyl halides. Further experiments showed that silyl-protected alkynes undergo electrophilic iodination and bromination under BrĂžnsted acid catalysis, whilst terminal alkynes require a cationic gold catalyst. The former reactions probably proceed via activation of the electrophile, whilst the latter reactions proceed via a gold(I) acetylide intermediate. Gold-catalysed halogenation was further combined with gold-catalysed hydration and subsequent annulation to provide convenient routes to iodomethyl ketones and five-membered aromatic heterocycles
Uniform generation in trace monoids
We consider the problem of random uniform generation of traces (the elements
of a free partially commutative monoid) in light of the uniform measure on the
boundary at infinity of the associated monoid. We obtain a product
decomposition of the uniform measure at infinity if the trace monoid has
several irreducible components-a case where other notions such as Parry
measures, are not defined. Random generation algorithms are then examined.Comment: Full version of the paper in MFCS 2015 with the same titl
Legionella spp. and legionellosis in southeastern Italy: disease epidemiology and environmental surveillance in community and health care facilities
<p>Abstract</p> <p>Background</p> <p>Following the publication of the Italian Guidelines for the control and prevention of legionellosis an environmental and clinical surveillance has been carried out in Southeastern Italy. The aim of the study is to identify the risk factors for the disease, so allowing better programming of the necessary prevention measures.</p> <p>Methods</p> <p>During the period January 2000 - December 2009 the environmental surveillance was carried out by water sampling of 129 health care facilities (73 public and 56 private hospitals) and 533 buildings within the community (63 private apartments, 305 hotels, 19 offices, 4 churches, 116 gyms, 3 swimming pools and 23 schools). Water sampling and microbiological analysis were carried out following the Italian Guidelines. From January 2005, all facilities were subject to risk analysis through the use of a standardized report; the results were classified as <it>good </it>(G), <it>medium </it>(M) and <it>bad </it>(B). As well, all the clinical surveillance forms for legionellosis, which must be compiled by physicians and sent to the Regional Centre for Epidemiology (OER), were analyzed.</p> <p>Results</p> <p><it>Legionella </it>spp. was found in 102 (79.1%) health care facilities and in 238 (44.7%) community buildings. The percentages for the contamination levels < 1,000, 1,000-10,000, > 10,000 cfu/L were respectively 33.1%, 53.4% and 13.5% for samples from health care facilities and 33.5%, 43.3% and 23.2% for samples from the community. Both in hospital and community environments, <it>Legionella pneumophila </it>serogroup (<it>L. pn </it>sg) 2-14 was the most frequently isolate (respectively 54.8% and 40.8% of positive samples), followed by <it>L. pn </it>sg 1 (respectively 31.3% and 33%). The study showed a significant association between M or B score at the risk analysis and <it>Legionella </it>spp. positive microbiological test results (p < 0.001). From clinical surveillance, during the period January 2001 - August 2009, 97 cases of legionellosis were reported to the OER: 88 of community origin and 9 nosocomial. The most frequent symptoms were: fever (93.8%), cough (70.1%), dyspnea (58.8%), shivering (56.7%). Radiological evidence of pneumonia was reported in 68%. The laboratory diagnostic methods used were: urinary antigen (54.3%), single antibody titer (19.8%), only seroconversion (11.1%), other diagnostic methods (14.8%).</p> <p>Conclusions</p> <p>Our experience suggests that risk analysis and environmental microbiological surveillance should be carried out more frequently to control the environmental spread of <it>Legionella </it>spp. Furthermore, the laboratory diagnosis of legionellosis cannot be excluded only on the basis of a single negative test: some patients were positive to only one of the diagnostic tests.</p
Measuring Egyptian Farmersâ Attitude Towards Staying Organic
Organic agriculture (OA) in Egypt is well-developed and still fast growing. Improving the relation between organic farmers and the other agents in the chain can provide a positive contribution to the whole organic chain competitiveness. One possible approach to investigate the farmersâ perceived role and satisfaction within the organic system is to explore the factors influencing their decision to stay organic. In particular, the aim of the present study was to measure the farmersâ attitude towards staying organic. Organic agricultural experts and institutional stakeholders were interviewed to complete a literature review and to obtain information about the Egyptian context. The survey questionnaire was pre-tested (n = 13) and then administered to a different sample (n = 232). A split-half validation procedure was used to evaluate and then confirm the factor structure. Explorative and confirmatory factor analysis yielded a final 29-item measure consisting of 8 distinct factors showing how organic agriculture influences a broad range of farmersâ life dimensions (environmental, economic, social, psychological). The significant role played by psychological and social factors in defining the farmersâ decision to stay organic emerged as a relatively unexpected outcome. The study supports the sustainable development of small family farmers, providing a useful tool to support the growth of organic production and consumption, mostly in developing countries. By monitoring farmersâ attitudes and perception towards OA, the instrument proposed in the present study can support policy makers, farmersâ organizations, civil society organizations (NGOs) and organic chains focal companies when defining policies, advocating campaigns, and chain coordination strategies for farmers involved in the organic food system development
Verb Semantics modulates neural activity in the left Lateral Temporal Cortex
Here we show that the implicit processing of telicity, dynamicity and agentivity differentially modulate neural activity across different brain clusters and, in particular, within lMTG. We found that selectivity for state and telic verbs identified the most anterior and the most posterior portion of lMTG, respectively. Furthermore, dynamicity and agentivity modulated brain responses in parietal and ventral extrastriate regions. The role of each property was clearly isolated, as the stimuli were specifically controlled for and the task design covertly assessed the representation of those properties. Different event types are differentially mapped based on their semantic representation and, in particular, lMTG represents conceptual semantic properties of verbs: specifically, that kind of conceptual information which is relevant to morphosyntax, that is, telicity, stativity and agentivity, that, unlike referential semantic features, and independently of them, govern morphosyntax in a specified way
Time-ordering and a generalized Magnus expansion
Both the classical time-ordering and the Magnus expansion are well-known in
the context of linear initial value problems. Motivated by the noncommutativity
between time-ordering and time derivation, and related problems raised recently
in statistical physics, we introduce a generalization of the Magnus expansion.
Whereas the classical expansion computes the logarithm of the evolution
operator of a linear differential equation, our generalization addresses the
same problem, including however directly a non-trivial initial condition. As a
by-product we recover a variant of the time ordering operation, known as
T*-ordering. Eventually, placing our results in the general context of
Rota-Baxter algebras permits us to present them in a more natural algebraic
setting. It encompasses, for example, the case where one considers linear
difference equations instead of linear differential equations
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