642 research outputs found
Analyse multidimensionnelle : application à la physique des noyaux en rotation rapide
École thématiqu
Bloc de la ligne blanche au secours de la chirurgie herniaire
Une hernie de la ligne blanche est une hernie située sur la ligne médiane entre les muscles grands droits de l'abdomen. Le diagnostic repose généralement sur un examen clinique. Plus rarement, il nécessite une échographie, voire un scanner.L'intervention pour soigner une hernie de la ligne blanche est le plus souvent réalisée en ambulatoire et sous anesthésie générale. Elle est réalisée par laparotomie, laparoscopie ou assistance robotique. Le choix de la technique dépend de l'épaisseur du tissu, de la taille de la hernie et de la présence d'interventions abdominales antérieures. L'intervention consiste à remettre l'intestin dans sa position initiale et à refermer le trou par lequel il est passé. Si le trou de la hernie est supérieur à 1 cm, un treillis est placé pour renforcer l'espace fermé par la chirurgie et prévenir les récidives.La diversité des pathologies et des antécédents des patients a nécessité une diversité de techniques anesthésiques plus adaptées d'où l'anesthésie locorégionale et lesblocs de la paroi abdominal
Effect of Thiourea on Yield and Quality of Potato (Solanum tuberosum L.)
A field experiment was carried out to study the effect of five concentrations (0, 250, 500, 750 and 1000 mM) of thiourea application on mother tubers on yield and quality attributes of harvested potato, variety Spunta in the region of Chott-Mariem in Tunisia. Treated tubers (Ш = 50 mm) were planted in field after breaking dormancy at a spacing of 80 cm x 30 cm according to completely randomized design (CRD) in three replications. Quality attributes of potato tubers especially fresh matter and dry matter of plant, total reducing sugars in leaves, tuber yield, number and diameter of tubers per plant and number of sprouts per tuber was measured. Soluble proteins and starch content in potato tubers were also quantified.In general we noted that application of thiourea showed significant influence on yield and on quality of tubers comparing to control. Maximum tuber yield per plant, maximum number of tubers per plant and maximum starch content was recorded with 250 mM of thiourea. Moreover, highest dry matter of potato plant was found also at this concentration. While increasing dose of thiourea thereafter it showed slight significant improvement and do not affect significantly the diameter of tubers comparing to control
Advances in Food Allergy Diagnosis
An accurate diagnosis of food allergy is extremely important to guide safe and yet not overly restrictive dietary management. The cornerstone of the diagnosis of food allergy is the clinical history; it allows appropriate selection of the allergens to be tested and interpretation of the results of allergy tests, namely Skin Prick Test (SPT), Specific IgE (sIgE) to allergen extracts and, more recently, specific IgE to allergen components and the Basophil Activation Test (BAT). SPT and sIgE to allergen extracts are very sensitive methods to detect IgE sensitization to a specific food and assess the possibility of spontaneous resolution. Cut-offs have been generated based on the probability of clinical reactivity during oral food challenges and can improve the specificity of SPT and sIgE, helping to confirm the diagnosis of food allergy. Specific IgE to allergen components refines food allergy diagnosis as it allows differentiating species-specific from cross-reactive allergens, aiding the differential diagnosis between a true and potentially severe food allergy from pollen-food syndrome or clinically irrelevant sensitization. The BAT is a new diagnostic test which has high specificity and sensitivity and can complement specific IgE, allowing the deferral of OFC in patients with a positive BAT. Depending on the likelihood of clinical allergy determined based on the combination of the history and the results of allergy tests, an oral food challenge may be indicated to confirm or exclude the diagnosis. Oral food challenge is the gold standard for the diagnosis of food allergy, but is a resource-intensive procedure with some level of risk involved; thus they are reserved for the equivocal cases. This review article discusses the above diagnostic techniques detailing the methods, utility, advantages and disadvantages.info:eu-repo/semantics/publishedVersio
PHYSIOLOGICAL MECHANISMS FOR POTATO DORMANCY RELEASE AND SPROUTING: A REVIEW
Potato ( Solanum tuberosum \ua0L.) tubers undergo a period of
dormancy, during which visible bud growth is inhibited. The length of
the dormancy is determined by environmental, physiological and hormonal
control mechanisms. Dormancy is the final stage of tuber life, which
serves to preserve tubers as organs of vegetative reproduction under
unfavourable growth conditions. Since the duration of potato tuber
dormancy and sprouting time bear significant economic importance, this
review considers the regulation of dormancy and sprouting of potato by
phytohormones and reactive oxygen species. Two phytohormones, ABA and
ethylene suppress tuber sprouting; however, the exact role of ethylene
remains to be elucidated. Cytokinins and gibberellins are required for
bud breaking and sprout growth, respectively. The auxin seems to play a
role in vascular development. Thus, tuber dormancy and sprouting can be
controlled in potato by manipulation of Reactive Oxygen Species (ROS),
especially H2O2\ua0metabolism via the inhibition of catalase (CAT)
activity.The possible mechanisms by which CAT inhibitors or
H2O2\ua0overcome dormancy and promote sprouting in the potato tuber
are discussed.La pomme de terre ( Solanum tuberosum \ua0L.) conna\ueet une
p\ue9riode de dormance durant laquelle la germination des bourgeons
visibles est inhib\ue9e. La dur\ue9e de dormance est
d\ue9termin\ue9e par des m\ue9canismes de contr\uf4le
environnemental, physiologique and hormonal. La dormance est le stade
final de la vie des tubercules servant \ue0 pr\ue9server les
tubercules comme organes de reproduction v\ue9g\ue9tative sous
condition de germination d\ue9favorables. Etant donn\ue9 que la
dur\ue9e de la dormance des tubercules de la pomme de terre et le
temps de rejet rev\ueatent une importance \ue9conomique
significative, cette revue consid\ue8re la r\ue9gulation de la
dormance et le rejet de la pomme de terre par des hormones et
d\u2019esp\ue8ces r\ue9actives d\u2019oxyg\ue8ne (ROS). Deux
phytohormones\ua0; ABA et \ue9thyl\ue8ne emp\ueachent le rejet
des tubercules\ua0; par ailleurs, le r\uf4le extractif de
l\u2019\ue9thyl\ue8ne reste \ue0 \ue9lucider. Les cytokinines
and les gibb\ue9rellines sont n\ue9cessaires dans
l\u2019\ue9limination des bourgeons et la croissance des rejets,
respectivement. L\u2019auxine semble jouer un r\uf4le dans le
d\ue9veloppement vasculaire. Ainsi, la dormance et les rejets des
tubercules peuvent \ueatre contr\uf4l\ue9s par manipulation
d\u2019esp\ue8ces r\ue9actives d\u2019oxyg\ue8ne (ROS),
sp\ue9cialement le m\ue9tabolisme du H2O2\ua0\ue0 travers
l\u2019inhibition de l\u2019activit\ue9 de la catalase (CAT). Les
m\ue9canismes possibles par lesquels les inhibiteurs du CAT ou
H2O2\ua0 surmontent la dormance et facilitent le rejet de la pomme de
terre sont discut\ue9s
Comportement agronomique d'une collection de pois (Pisum sativum L)
Agronomical Behaviour of a Pea Collection (Pisum sativum L.). This experience was achieved under greenhouse conditions. Twelve genotypes of pea were used (Asgrow, Jumbo, Lincoln, Merveille de Kelvedon, Purser, Rajai Torpe, Snajor Kosep, Korai,Wando, Rondo, local genotype, Major Kosep Korai and Surgevil). They were cultivated on peat during 5.5 months (from October to April). Some agronomical parameters were studied: resistance to diseases, (Powdery-mildew, mildew, top yellow virus, anthracnose, browning), fresh matter, number of branches/plant, number of flowers/plant, number of pods/ plant and the yield of grains /plant. Results showed that only the genotype Purser is resistant to all diseases and Surgevil is sensitive only to the Top Yellow virus. The local genotype is sensitive to three frequent diseases (Powdery-mildew, mildew and Anthracnose). With regard to vegetative growth, the highest yield of fresh matter do not contribute towards a high fertility rate. In fact, only the genotypes having a weak yield of fresh matter (Snajor Kosep Korai, Asgrow, Major Kosep Korai, Rajai Torpe and Purser) have the most important rate of fertility (> 30%). Within this group, the most important yield (> 9 g/plant) is a result of high: number of pods/plant (7.5 to 21.6) and of grains/pod (2.8 to 4.92). Finally, genotype Purser should be retained for farmers and programs of genetic amelioration for its resistance to diseases and agronomical performances
Elements Discrimination in the Study of Super-Heavy Elements using an Ionization Chamber
Dedicated ionization chamber was built and installed to measure the energy
loss of very heavy nuclei at 2.7 MeV/u produced in fusion reactions in inverse
kinematics (beam of 208Pb). After going through the ionization chamber,
products of reactions on 12C, 18O targets are implanted in a Si detector. Their
identification through their alpha decay chain is ambiguous when their
half-life is short. After calibration with Pb and Th nuclei, the ionization
chamber signal allowed us to resolve these ambiguities. In the search for rare
super-heavy nuclei produced in fusion reactions in inverse or symmetric
kinematics, such a chamber will provide direct information on the nuclear
charge of each implanted nucleus.Comment: submitted to NIMA, 10 pages+4 figures, Latex, uses elsart.cls and
grahpic
Collisionless Shock Acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves
We recently proposed a new technique of plasma tailoring by laser-driven
hydrodynamic shockwaves generated on both sides of a gas jet [J.-R. Marqu\`es
et al., Phys. Plasmas 28, 023103 (2021)]. In the continuation of this numerical
work, we studied experimentally the influence of the tailoring on proton
acceleration driven by a high-intensity picosecond-laser, in three cases:
without tailoring, by tailoring only the entrance side of the ps-laser, or both
sides of the gas jet. Without tailoring the acceleration is transverse to the
laser axis, with a low-energy exponential spectrum, produced by Coulomb
explosion. When the front side of the gas jet is tailored, a forward
acceleration appears, that is significantly enhanced when both the front and
back sides of the plasma are tailored. This forward acceleration produces
higher energy protons, with a peaked spectrum, and is in good agreement with
the mechanism of Collisionless Shock Acceleration (CSA). The spatio-temporal
evolution of the plasma profile was characterized by optical shadowgraphy of a
probe beam. The refraction and absorption of this beam was simulated by
post-processing 3D hydrodynamic simulations of the plasma tailoring. Comparison
with the experimental results allowed to estimate the thickness and
near-critical density of the plasma slab produced by tailoring both sides of
the gas jet. These parameters are in good agreement with those required for
CSA
Spin-rotor Interpretation of Identical Bands and Quantized Alignment in Superdeformed A 190 Nuclei
The ``identical'' bands in superdeformed mercury, thallium, and lead nuclei
are interpreted as examples of orbital angular momentum rotors with the weak
spin-orbit coupling of pseudo- symmetries and supersymmetries.Comment: 15 pages, revtex 3.0, 7 figures available upon request from
[email protected]
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