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Traumatic spinal cord injuries (TSCI) have devastating consequences on patients’ quality of life. More specifically, TSCI with spinal fractures (TSCIF) have the most severe neurological impairment, although limited data are available. This study aimed at providing data and analyzing TSCIF in a level I trauma center in the province of Québec, Canada.
Two hundred eighty-two TSCIF were reviewed. Spinal injuries and neurological impairment were assessed with AO classification and AIS, respectively. Variables included age, sex, cause, location, mechanism of injury (MOI), and severity of TSCIF. Chi-squared Pearson determined significant associations (p < 0.05).
Male-to-female ratio was 3.21:1. Patients were 42.5 ± 18.7 years. The leading causes of TSCIF were high-energy falls (28.4%), cars (26.2%) and vehicle without restraint system (motorcycle, all-terrain vehicle, snowmobile, and bicycle) (21.3%). Vehicle collisions, pooling cars and unrestrained vehicles, mostly affected the 20–49-year population (62.2%). The main MOI was distraction in males (47.9%), and axial compression in females (44.8%). There were significant associations between causes and injured spinal level, as well as between MOI and injured spinal level, sex, and TSCIF severity. Most patients involved in unrestrained vehicle accidents sustained a thoracolumbar spine distraction with complete motor deficit. A severe neurologic deficit affected most patients following car accidents that caused cervical spine distraction or axial torsion.
In Québec, most TSCIF caused by vehicle collisions affect a young population and have severe neurological impairments. Future efforts should focus on better understanding accidents involving the unrestrained vehicle category to further improve preventive measures.
As an extension of a central limit theorem established by Svante Janson, we prove a Berry–Esseen inequality for a sum of independent and identically distributed random variables conditioned by a sum of independent and identically distributed integer-valued random variables.
Recent observations of solar flares at high-frequencies have provided evidence of a new spectral component with fluxes increasing with frequency in the sub-THz to THz range. This new component occurs simultaneously but is separated from the well-known microwave spectral component that maximizes at frequencies of a few to tens of GHz. The aim of this work is to study in detail a mechanism recently suggested to describe the double-spectrum feature observed in solar flares based on the physical process known as microbunching instability, which occurs with high-energy electron beams in laboratory accelerators.
be a maximal order in a definite quaternion algebra over
of prime discriminant
a small prime. We describe a probabilistic algorithm which, for a given left
-ideal, computes a representative in its left ideal class of
-power norm. In practice the algorithm is efficient and, subject to heuristics on expected distributions of primes, runs in expected polynomial time. This solves the underlying problem for a quaternion analog of the Charles–Goren–Lauter hash function, and has security implications for the original CGL construction in terms of supersingular elliptic curves.
In the present study, the effect of flax hulls with or without flax oil bypassing the rumen on the expression of lipogenic genes in the mammary tissue of dairy cows was investigated. A total of eight dairy cows were used in a replicated 4 × 4 Latin square design. There were four periods of 21 d each and four treatments: control diet with no flax hulls (CONT); diet with 9·88 % flax hulls in the DM (HULL); control diet with 500 g flax oil/d infused in the abomasum (COFO); diet with 9·88 % flax hulls in the DM and 500 g flax oil/d infused in the abomasum (HUFO). A higher mRNA abundance of sterol regulatory element binding transcription factor, fatty acid (FA) synthase, lipoprotein lipase (LPL), PPARγ1, stearoyl-CoA desaturase (SCD) and acetyl-coenzyme A carboxylase-α was observed in cows fed HULL than in those fed CONT, and HUFO had the opposite effect. Compared with CONT, COFO and HUFO lowered the mRNA abundance of SCD, which may explain the lower proportions of MUFA in milk fat with flax oil infusion. The mRNA abundance of LPL in mammary tissue and proportions of long-chain FA in milk fat were higher in cows fed COFO than in those fed CONT. The highest proportions of trans FA were observed when cows were fed HULL. The present study demonstrates that flax hulls with or without flax oil infusion in the abomasum can affect the expression of lipogenic genes in the mammary tissue of dairy cows, which may contribute to the improvement of milk FA profile.
The effects of flax meal (FM) on the activity of antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT)) in the blood, mammary tissue and ruminal fluid, and oxidative stress indicators (thiobarbituric acid-reactive substances (TBARS) and 1,1-diphenyl-2-picrylhydrazyl-scavenging activity) in the milk, plasma and ruminal fluid of dairy cows were determined. The mRNA abundance of the antioxidant enzymes and oxidative stress-related genes was assessed in mammary tissue. A total of eight Holstein cows were used in a double 4 × 4 Latin square design. There were four treatments in the diet: control with no FM (CON) or 5 % FM (5FM), 10 % FM (10FM) and 15 % FM (15FM). There was an interaction between treatment and time for plasma GPx and CAT activities. Cows supplemented with FM had a linear reduction in TBARS at 2 h after feeding, and there was no treatment effect at 0, 4 and 6 h after feeding. TBARS production decreased in the milk of cows fed the 5FM and 10FM diets. There was a linear increase in nuclear factor (erythroid-derived 2)-like 2 (NFE2L2) mRNA abundance in mammary tissue with FM supplementation. A linear trend for increased mRNA abundance of the CAT gene was observed with higher concentrations of FM. The mRNA abundance of CAT, GPx1, GPx3, SOD1, SOD2, SOD3 and nuclear factor of κ light polypeptide gene enhancer in B-cells (NFKB) genes was not affected by the treatment. These findings suggest that FM supplementation can improve the oxidative status of Holstein cows as suggested by decreased TBARS production in ruminal fluid 2 h post-feeding and increased NFE2L2/nuclear factor-E2-related factor 2 (Nrf2) mRNA abundance in mammary tissue.
The objectives of the study were to investigate the effects of dietary supplementation of flax hulls and/or flax oil on the activity of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX)) in plasma and the mammary gland and the relative mRNA abundance of antioxidant genes in the mammary gland of dairy cows. A total of eight dairy cows were used in a replicated 4 × 4 Latin square design. There were four treatments: control with no flax hulls (CONT), 9·88 % flax hulls in the DM (HULL), control with 500 g flax oil/d infused in the abomasum (COFO), 9·88 % flax hulls in the DM and 500 g flax oil/d infused in the abomasum (HUFO). Plasma GPX activity tended to decrease with flax oil supplementation. Cows fed HULL had higher levels of CAT, GPX1 and SOD1 mRNA in the mammary gland and lower mRNA abundance of GPX3, SOD2 and SOD3 compared with those fed CONT. Abundance of CAT, GPX1, GPX3, SOD2 and SOD3 mRNA was down-regulated in the mammary gland of cows fed HUFO compared to those fed CONT. The mRNA abundance of CAT, GPX1, GPX3 and SOD3 was lower in the mammary gland of cows fed COFO than in the mammary gland of cows fed CONT. The present study demonstrates that flax hulls contribute to increasing the abundance of some antioxidant genes, which can contribute to protecting against oxidative stress damage occurring in the mammary gland and other tissues of dairy cows.
Porous materials, concentrated colloidal suspensions are example of confining systems developing large specific surface and presenting a rich variety of shapes. Such an interfacial confinement strongly influences the molecular dynamics of embedded fluids and the diffusive motion of entrapped Brownian particles. An individual trajectory near the interface can be described as an alternate succession of adsorption steps and random flights in the bulk. Statistical properties of these random flights in various interfacial confining systems are determinant to understand the full transport process. Related to first passage processes, these properties play a central role in numerous problems such as the mean first exit time in a bounded domain, heterogeneous catalytic reactivity and nuclear magnetic relaxation in complex and biological fluids. In the present work, we first consider the various possibilities to connect two points of a smooth interface by a random flight in the bulk. Second, we analyze at the theoretical and experimental points of view a way to probe Brownian flights statistics. Implications concerning diffusive transport in disordered porous materials are discussed.
The potential importance of backfilling and plugging in underground radioactive waste repositories has led differents research institutions around the world (SKB in Sweden, CEA in France, AECL in Canada, etc.) to carry out extensive studies of swelling clay materials for the development of engineered barriers. These materials, which have to be emplaced in underground conditions, should combine a variety of complementary properties from both the hydro-thermo-mechanical and geochemical viewpoints: impermeability, swelling ability in order to fill all void space, heat transfer and retention capacity for the most noxious radionuclides. For years, the scientific community has acknowledged the fact that smectite clays best exhibit these properties and, thus, most of the research effort has been devoted to this type of materials. The aim of such studies is to try and link the microscopic characteristics of the material (mineralogy, geochemical properties, microstructure, etc.) to its macroscopic behaviour (swelling properties, etc…).
The strength of the association between intensive care unit (ICU)-acquired nosocomial infections (NIs) and mortality might differ according to the methodological approach taken.
TO assess the association between ICU-acquired NIs and mortality using the concept of population-attributable fraction (PAF) for patient deaths caused by ICU-acquired NIs in a large cohort of critically ill patients.
Eleven ICUs of a French university hospital.
We analyzed surveillance data on ICU-acquired NIs collected prospectively during the period from 1995 through 2003. The primary outcome was mortality from ICU-acquired NI stratified by site of infection. A matched-pair, case-control study was performed. Each patient who died before ICU discharge was defined as a case patient, and each patient who survived to ICU discharge was denned as a control patient. The PAF was calculated after adjustment for confounders by use of conditional logistic regression analysis.
Among 8,068 ICU patients, a total of 1,725 deceased patients were successfully matched with 1,725 control Patients. The adjusted PAF due to ICU-acquired NI for patients who died before ICU discharge was 14.6% (95% confidence interval [CI], 14.4%—14.8%). Stratified by the type of infection, the PAF was 6.1% (95% CI, 5.7%–6.5%) for pulmonary infection, 3.2% (95% CI, 2.8%–3.5%) for central venous catheter infection, 1.7% (95% CI, 0.9%–2.5%) for bloodstream infection, and 0.0% (95% CI, –0.4% to 0.4%) for urinary tract infection.
ICU-acquired NI had an important effect on mortality. However, the statistical association between ICU-acquired NI and mortality tended to be less pronounced in findings based on the PAF than in study findings based on estimates of relative risk. Therefore, the choice of methods does matter when the burden of NI needs to be assessed.
The second, or informal, economy developed later in Lubumbashi (DRC) than it had in Kinshasa. The Katanga metropolis, long protected from the process of informalization thanks to its large industrial complexes, suffered seriously from the crisis of the 1990s which led to the collapse of the mining industry and, more generally, of the whole salaried sector. After a brief history of the city and of the state of play of the informal economy, this article attempts a detailed analysis of this economy's lexicon. Expressions newly created from Swahili, French and other languages provide an excellent point of entry into the concrete practices of this sector, as well as the representations and morality on which such practices are based. Strongly associated with expressions of energy, cunning and conspiracy, the vocabulary emerging from the second economy bears witness to the appreciation of the ‘anti-hero’ and demonstrates the inception of a new moral economy in which the state and the powerful have become targets of legitimate predation based on the principle of redistribution.
In this paper we consider a free boundary problem for a nonlinear
parabolic partial differential equation. In particular, we are
concerned with the inverse problem, which means we know the
behavior of the free boundary a priori and would like a solution,
e.g. a convergent series, in order to determine what the
trajectories of the system should be for steady-state to
steady-state boundary control. In this paper we combine two
issues: the free boundary (Stefan) problem with a quadratic
nonlinearity. We prove convergence of a series solution and give a
detailed parametric study on the series radius of convergence.
Moreover, we prove that the parametrization can indeed can be used
for motion planning purposes; computation of the open loop motion
planning is straightforward. Simulation results are given and we
prove some important properties about the solution. Namely, a weak
maximum principle is derived for the dynamics, stating that the
maximum is on the boundary. Also, we prove asymptotic positiveness
of the solution, a physical requirement over the entire domain, as
the transient time from one steady-state to another gets large.
The purse-seiners of the Java Sea use light and fish aggregating devices (FAD) to concentrate and catch small pelagic fish (Decapterus sp., Amblygaster sirm, Sardinella gibbosa). This sets a question about the interaction between fish and fishing vessels. Relevant estimates of fishing mortality and fishing effort require an understanding of this interaction. To gain information on this relationship, acoustic surveys were performed on the fishing grounds and the present paper analyses these data. Using acoustic surveys, the fish density was measured and the number of schools was counted per sea surface unit. The fishing vessels were located by radar. Acoustic data were stratified into two groups, one where fishing vessels were present and the other where they were not. This stratification was tested for by resampling the data. Day and night sampled data were analysed in each strata separately. Variograms were computed to characterise spatial structure both for the fish and the purse-seiners. Contingency tables between number of schools and fish density were computed to characterise the relation between biomass and schools for the day and the night when seiners are absent or present. At night, in the absence of purse-seiners, the number of schools increase and fish rise from the bottom. In areas where purse-seiners are present this natural phenomenon is stronger. It also changes the spatial structure both of the fish density and the school abundance. The spatial structure of the vessels is similar to that of the fish density. The fishermen seem to be able to detect by day fish concentrations which will be fished later by night.
Drawing on observations among the Luba of Shaba (Zaire) and their neighbours, this article analyses the relationship between the sacred king and the spirits. The strong connection which unites them appears to be an important source of the symbolic efficacy of royalty, too often reduced to the single theme of the king's monstrosity or ambivalence. The epic of the kingdom is used as a main theme, as it subtly evokes three institutions at the heart of this problem, the royal ancestors' cult, the enthronement process which stresses the agreement of the spirits as to a candidate, and the use of relics in order to pass on a spiritual principle. These royal rites appear to be an elaboration of commoner rites, of which they constitute a complex form. The specificity of the king appears more clearly in the use of relics which makes him the living continuation of his predecessors.