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1.
Eur Phys J C Part Fields ; 75(5): 226, 2015.
Article in English | MEDLINE | ID: mdl-26041975

ABSTRACT

The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.

2.
Eur Phys J C Part Fields ; 75(1): 1, 2015.
Article in English | MEDLINE | ID: mdl-25983644

ABSTRACT

The production of the strange and double-strange baryon resonances ([Formula: see text], [Formula: see text]) has been measured at mid-rapidity ([Formula: see text][Formula: see text]) in proton-proton collisions at [Formula: see text] [Formula: see text] 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the [Formula: see text] pentaquark, decaying in the [Formula: see text] channel, has been carried out but no evidence is seen.

4.
Phys Rev Lett ; 113(23): 232504, 2014 Dec 05.
Article in English | MEDLINE | ID: mdl-25526123

ABSTRACT

We present the first measurement at the LHC of exclusive J/ψ photoproduction off protons, in ultraperipheral proton-lead collisions at sqrt[s_{NN}]=5.02 TeV. Events are selected with a dimuon pair produced either in the rapidity interval, in the laboratory frame, 2.5

5.
Eur Phys J C Part Fields ; 74(8): 2974, 2014.
Article in English | MEDLINE | ID: mdl-25814905

ABSTRACT

The inclusive production cross sections at forward rapidity of [Formula: see text], [Formula: see text], [Formula: see text](1S) and [Formula: see text](2S) are measured in [Formula: see text] collisions at [Formula: see text] with the ALICE detector at the LHC. The analysis is based on a data sample corresponding to an integrated luminosity of 1.35 pb[Formula: see text]. Quarkonia are reconstructed in the dimuon-decay channel and the signal yields are evaluated by fitting the [Formula: see text] invariant mass distributions. The differential production cross sections are measured as a function of the transverse momentum [Formula: see text] and rapidity [Formula: see text], over the ranges [Formula: see text] GeV/c for [Formula: see text], [Formula: see text] GeV/c for all other resonances and for [Formula: see text]. The measured cross sections integrated over [Formula: see text] and [Formula: see text], and assuming unpolarized quarkonia, are: [Formula: see text] [Formula: see text]b, [Formula: see text] [Formula: see text]b, [Formula: see text] nb and [Formula: see text] nb, where the first uncertainty is statistical and the second one is systematic. The results are compared to measurements performed by other LHC experiments and to theoretical models.

6.
Phys Rev Lett ; 111(22): 222301, 2013 Nov 27.
Article in English | MEDLINE | ID: mdl-24329443

ABSTRACT

The ALICE measurement of K(S)(0) and Λ production at midrapidity in Pb-Pb collisions at √(s(NN))=2.76 TeV is presented. The transverse momentum (p(T)) spectra are shown for several collision centrality intervals and in the p(T) range from 0.4 GeV/c (0.6 GeV/c for Λ) to 12 GeV/c. The p(T) dependence of the Λ/K(S)(0) ratios exhibits maxima in the vicinity of 3 GeV/c, and the positions of the maxima shift towards higher p(T) with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate p(T) is not observed in pp interactions at √s=0.9 TeV and at √s=7 TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured p(T) spectra above 2 GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of p(T), models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the p(T) dependence of the Λ/K(S)(0) ratio.

7.
Phys Rev Lett ; 111(16): 162301, 2013 Oct 18.
Article in English | MEDLINE | ID: mdl-24182258

ABSTRACT

We report on the first measurement of inclusive J/ψ elliptic flow v2 in heavy-ion collisions at the LHC. The measurement is performed with the ALICE detector in Pb-Pb collisions at √(s(NN))=2.76 TeV in the rapidity range 2.5

8.
Eur Phys J C Part Fields ; 73(11): 2617, 2013.
Article in English | MEDLINE | ID: mdl-25814847

ABSTRACT

The ALICE Collaboration at the LHC has measured the J/ψ and ψ' photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at [Formula: see text]. The charmonium is identified via its leptonic decay for events where the hadronic activity is required to be minimal. The analysis is based on an event sample corresponding to an integrated luminosity of about 23 µb-1. The cross section for coherent and incoherent J/ψ production in the rapidity interval -0.9

9.
Eur Phys J C Part Fields ; 73(12): 2662, 2013.
Article in English | MEDLINE | ID: mdl-25814850

ABSTRACT

Differential cross sections of charged particles in inelastic pp collisions as a function of pT have been measured at [Formula: see text] at the LHC. The pT spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual [Formula: see text] cannot be described by NLO-pQCD, the relative increase of cross section with [Formula: see text] is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at [Formula: see text] up to pT=50 GeV/c as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus collisions.

10.
Phys Rev Lett ; 111(23): 232302, 2013 Dec 06.
Article in English | MEDLINE | ID: mdl-24476260

ABSTRACT

The directed flow of charged particles at midrapidity is measured in Pb-Pb collisions at √(s(NN))=2.76 TeV relative to the collision symmetry plane defined by the spectator nucleons. A negative slope of the rapidity-odd directed flow component with approximately 3 times smaller magnitude than found at the highest RHIC energy is observed. This suggests a smaller longitudinal tilt of the initial system and disfavors the strong fireball rotation predicted for the LHC energies. The rapidity-even directed flow component is measured for the first time with spectators and found to be independent of pseudorapidity with a sign change at transverse momenta p(T) between 1.2 and 1.7 GeV/c. Combined with the observation of a vanishing rapidity-even p(T) shift along the spectator deflection this is strong evidence for dipolelike initial density fluctuations in the overlap zone of the nuclei. Similar trends in the rapidity-even directed flow and the estimate from two-particle correlations at midrapidity, which is larger by about a factor of 40, indicate a weak correlation between fluctuating participant and spectator symmetry planes. These observations open new possibilities for investigation of the initial conditions in heavy-ion collisions with spectator nucleons.

11.
Phys Rev Lett ; 111(10): 102301, 2013 Sep 06.
Article in English | MEDLINE | ID: mdl-25166659

ABSTRACT

Azimuthally anisotropic distributions of D0, D+, and D*+ mesons were studied in the central rapidity region (|y|<0.8) in Pb-Pb collisions at a center-of-mass energy sqrt[sNN]=2.76 TeV per nucleon-nucleon collision, with the ALICE detector at the LHC. The second Fourier coefficient v2 (commonly denoted elliptic flow) was measured in the centrality class 30%-50% as a function of the D meson transverse momentum pT, in the range 2-16 GeV/c. The measured v2 of D mesons is comparable in magnitude to that of light-flavor hadrons. It is positive in the range 2

12.
Minerva Chir ; 66(1): 21-40, 2011 Feb.
Article in Italian | MEDLINE | ID: mdl-21389922

ABSTRACT

AIM: Can the tension-free suturless technique, used in the surgical treatment of inguinal hernia, to be the gold standard for treatment of inguinal hernia? METHODS: The tension-free suturless technique is often criticized as a fundamental principle: do not have suture. The criticism stems from concern that the mesh can migrate and cause damage to important anatomical structures. We conducted a study on the mobility of prosthesis on 33 patients, by using titanium clips that we have fixed on the meshes corner, X-rays over time, done at last, a follow-up of ten years. RESULTS: The study shows that the prosthesis moves together with the anatomical space in which there is the forces present in the inguinal canal: gravity, intra-abdominal pressure, reactive force ascending gait. Across thirty-three patients have relapsed in the first six months and two recurrences in ten years, in the reconstitution of the neo-orifice, through which passes the cord. In the remaining patients the mesh were relocated upward and medially (as identified by the clips of the increase of 10-15%). CONCLUSION: Our study shows that the mesh migrates upwards and medially. Migration is more or less, depending on the patient's age and quality of its tissue. Fix the prosthesis is good practice to secure at the flag on the inguinal ligament leads to two advantages: not to frustrate the principle tension-free, since the fixed prosthesis on one side does not create moments of tension, and prevent the prosthesis returns to the opening road to relapse.


Subject(s)
Foreign-Body Migration/epidemiology , Hernia, Inguinal/surgery , Prosthesis Implantation/methods , Surgical Mesh/adverse effects , Suture Techniques , Aged , Ambulatory Surgical Procedures/methods , Biomechanical Phenomena , Female , Follow-Up Studies , Foreign-Body Migration/prevention & control , Hernia, Inguinal/diagnostic imaging , Hernia, Inguinal/therapy , History, 18th Century , History, 19th Century , History, 20th Century , History, Ancient , History, Medieval , Humans , Laparotomy/history , Male , Middle Aged , Patient Selection , Radiography , Recurrence , Trusses/history
13.
G Chir ; 27(8-9): 324-7, 2006.
Article in Italian | MEDLINE | ID: mdl-17064493

ABSTRACT

Authors report an uncommon case of spontaneous rupture of common iliac artery in a man 43 years old with Ehlers-Danlos syndrome. The clinical presentation was devious in the beginning and catastrophic after few hours with a haemo-peritoneum and haemorragic shock. The Ehlers-Danlos syndrome is a rare affection of the connective tissue with an incidence of 1/5000, representing one of the most common disorders of the connective tissue. This disease is characterized by the fragility of arteries, intestine and uterus. Its presentation is often catastrophic, with rupture of a big artery, rupture of uterus during pregnancy or bowel perforation. The mean age of death in subjects with Ehlers-Danlos syndrome is 45 years. This syndrome is inherited in most cases in an autosomal dominant manner; 50% of the cases are due to new mutations. A minority of cases, due to deficit of tenascina X, is inherited in an autosomal recessive manner.


Subject(s)
Ehlers-Danlos Syndrome/complications , Iliac Artery , Adult , Humans , Male , Rupture, Spontaneous
14.
G Chir ; 27(3): 97-9, 2006 Mar.
Article in Italian | MEDLINE | ID: mdl-16681869

ABSTRACT

Mucinous cystadenomas of the appendix are rare tumours. In this article we describe the case of a young woman who presented with abdominal pain and a clinical pattern likely to a chronic appendicitis. At laparotomy we found a dilatation of the appendix which contained an abundant quantity of mucus. Histological examination showed a mucinous cystadenoma of the appendix. This neoplasm requires a surgical treatment, usually only appendectomy and right hemicolectomy in case of involvement of the caecum. During operation, the surgeon must take care in handling the appendix because of the risk of rupture with consequent dissemination of epithelial cells in the peritoneal cavity (pseudomyxoma peritonei).


Subject(s)
Appendiceal Neoplasms/complications , Cystadenoma, Mucinous/complications , Mucocele/etiology , Appendectomy , Appendiceal Neoplasms/diagnosis , Appendiceal Neoplasms/surgery , Cystadenoma, Mucinous/diagnosis , Cystadenoma, Mucinous/surgery , Female , Humans , Laparotomy , Middle Aged , Mucocele/diagnosis , Mucocele/surgery , Treatment Outcome
15.
G Chir ; 26(10): 362-4, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16371186

ABSTRACT

Inflammatory myofibroblastic pseudotumors (IPM) are very rare tumor characterized by unpredictable clinical behaviour. They arise in soft tissues of almost every organ and the most common site is the lung. Over 200 cases of inflammatory myofibroblastic pseudotumor of the lung have been described in literature. Intra-abdominal IMP are very rare. We describe a case of intra-abdominal IMP in a boy of 15 years old who presented symptoms and signs of acute appendicitis. Exploratory laparotomy revealed a mass in the peritoneal cavity. The mass was removed. The histologic examination showed that it was an IMP. Surgical treatment was the only therapy. Six months after the surgical operation the patient has no sign of illness.


Subject(s)
Granuloma, Plasma Cell/surgery , Neoplasms, Muscle Tissue/surgery , Peritoneal Neoplasms/surgery , Adolescent , Diagnosis, Differential , Granuloma, Plasma Cell/pathology , Humans , Male , Neoplasms, Muscle Tissue/pathology , Peritoneal Neoplasms/pathology , Treatment Outcome
16.
G Chir ; 26(1-2): 25-8, 2005.
Article in Italian | MEDLINE | ID: mdl-15847090

ABSTRACT

The pheochromocytoma is a very rare neoplasm, which originates in 98% of cases in the adrenal medulla; it is often bilateral in familial syndromes. It is more frequent in syndromes like MEN2, von Hippel-Lindau disease, and neuofribromatosis type 1. In this article the Authors report a case of a young woman with a large adrenal pheochromocytoma, that presented by an acute abdomen; the treatment was explorative laparotomy with unilateral adrenalectomy. Therapy of this tumour is founded on surgery, plus chemiotherapy radiotherapy or treatment with 131I-MIBG (iodine-131-metaiodobenzylguanidine in malignant cases (10%). According with the absence of a correlation between pathological findings and clinical behaviour, a long-term follow up is indispensable.


Subject(s)
Abdomen, Acute/etiology , Adrenal Gland Neoplasms/complications , Pheochromocytoma/complications , Adrenal Gland Neoplasms/diagnostic imaging , Adrenal Gland Neoplasms/surgery , Adrenalectomy , Adult , Female , Follow-Up Studies , Humans , Immunohistochemistry , Pheochromocytoma/diagnostic imaging , Pheochromocytoma/surgery , Radiography, Abdominal , Rupture, Spontaneous , Time Factors , Tomography, X-Ray Computed , Ultrasonography
17.
G Chir ; 26(11-12): 419-21, 2005.
Article in Italian | MEDLINE | ID: mdl-16472419

ABSTRACT

Splenic marginal zone lymphomas are rare tumors which take origin from the B cells. More common in the elderly, often asymptomatic, they can present with abdominal pain, splenomegaly and cytopenia and have an indolent clinical course. We describe a case of a women 79 years old who presented with abdominal pain, fever and splenomegaly. Computed tomography demonstrated splenomegaly with an area of low density in the spleen. Only by laparotomy and splenectomy the correct diagnosis was possible. Because of the indolent course of this kind of lymphomas, splenectomy is the main treatment for patients with abdominal pain, splenomegaly and cytopenia. If there is no pain and no cytopenia, the treatment can be only wait and see. Only in case of progression of disease chemotherapy can be employed.


Subject(s)
Lymphoma , Splenic Neoplasms , Abdominal Pain/etiology , Aged , Diagnosis, Differential , Disease Progression , Female , Humans , Immunohistochemistry , Laparotomy , Lymphoma/complications , Lymphoma/diagnosis , Lymphoma/diagnostic imaging , Lymphoma/pathology , Lymphoma/surgery , Prognosis , Radiography, Abdominal , Spleen/pathology , Splenectomy , Splenic Neoplasms/complications , Splenic Neoplasms/diagnosis , Splenic Neoplasms/diagnostic imaging , Splenic Neoplasms/pathology , Splenic Neoplasms/surgery , Splenomegaly/diagnostic imaging , Splenomegaly/etiology , Splenomegaly/pathology , Splenomegaly/surgery , Tomography, X-Ray Computed
18.
G Chir ; 26(11-12): 446-8, 2005.
Article in Italian | MEDLINE | ID: mdl-16472426

ABSTRACT

Laser treatment of primary varicose veins of the legs is a new mini-invasive technique which represent an alternative to the safenectomy. Endovascular laser treatment is based on the employ of laser to destroying the vascular wall and inducing fibrosis. This technique is not without complications: burns, paraesthesias, haematomas, but most of all disappear in few days. Encouraged by the promising results reported in literature, we have performed 18 laser ablation of greater saphenous vein since 2003 till today. Our patients had a good post-operative course and a follow up without troubles (3-17 months). We think that laser treatment is effective in the treatment of the primary varicose veins of the legs. It requests attention and experience in dosing the laser energy for minimizing the complications. Today there isn't long term follow up in literature.


Subject(s)
Laser Therapy , Saphenous Vein/surgery , Varicose Veins/surgery , Adult , Aged , Female , Follow-Up Studies , Humans , Laser Therapy/adverse effects , Male , Middle Aged , Minimally Invasive Surgical Procedures , Time Factors
20.
Vet Res ; 25(2-3): 218-22, 1994.
Article in French | MEDLINE | ID: mdl-8038788

ABSTRACT

The relationships between nutrition and udder inflammation/infection were studied in the dairy cow using an ecopathological approach. The study ('enquête écopathologique Bretagne') was performed over 4 yr in French herds with high-lactating cows. A long distribution time of Italian ryegrass silage and a low quantity of dietary cereal-based concentrates in the first 2 months of lactation was linked with low milk leukocyte counts, probably due to a high dietary energetic level or to a polyunsaturated fatty acid imbalance and a subsequent decrease in the synthesis of leukotriene LTB4. In the late gestation period, a long distribution time of fresh English rye-grass, which induced high uraemia and a larger distribution of vitamins A, D and E, was related to lower frequencies of major pathogens in the milk.


Subject(s)
Animal Nutritional Physiological Phenomena , Mastitis, Bovine/etiology , Animal Feed , Animals , Bacteria/growth & development , Cattle , Energy Intake , Fatty Acids, Unsaturated/metabolism , Female , Leukocyte Count/veterinary , Leukotriene B4/biosynthesis , Milk/cytology , Milk/microbiology , Vitamins/administration & dosage
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