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This review focuses on fluid management of critically ill patients. The topic is addressed based on 10 single questions with simplified answers that provide clinicians with the basic information needed at the point of care in treating patients in the Intensive Care Unit. The review has didactic purposes and may serve both as an update on fluid management and as an introduction to the subject for novices in critical care.

In order to elucidate the origin of the interplay between charge density wave (CDW) and superconductivity in 1T-TaS2, we have synthesized powder samples of pure and C-intercalated 1T-CxTaS2 by means of a multi-anvil high-pressure synthesis method. We have found that single-phase samples are obtained in the 2-6 GPa range at 400 °C and for x=0-0.3. The structural, magnetic and transport properties of all samples have been investigated by means of neutron and x-ray diffraction, dc magnetization and dc electrical resistivity. For all x values including x=0, the data show that the CDW phase is suppressed concomitant to an abrupt onset of superconductivity, with Tc=3.2 K for x=0. The Tc value turns out to be weakly dependent on x, with a maximum Tc=3.8 K for x=0.2. This onset is accompanied by a crossover of magnetic behavior from paramagnetic Pauli-like to paramagnetic Curie-Weiss-like with effective moment  1.2 B/Ta, which suggests that a ionic picture is suitable for the superconducting phase, but not for the CDW phase. The analysis of the dependence of the a and c lattice parameters upon x as well as upon the synthesis conditions shows that the onset of superconductivity is mainly ascribed to unusual changes of the unit cell induced by the high-pressure synthesis. Specifically, the ex-situ lattice parameters exhibit a significantly larger c-axis parameter and a shrinking of the a-axis parameter stabilized by the high-pressure synthesis route. We argue that the above suppression of the CDW phase is induced by a broadening of the relevant 5d(t2g) band which stabilizes the metallic and superconducting phases. This scenario suggests that the strength of the electronic correlations are the main control parameter of the CDW-superconductivity competition in 1T-TaS2.

In this lecture we will introduce the general characteristics of non-resonant X-ray inelastic scattering, in particular its scattering and absorption cross-section as well as its kinematic conditions. We will then present how it is possible to achieve meV energy resolution with keV X-rays, hence performing light inelastic scattering of thermal excitations with a wavelength of the order of inter-atomic spacing in liquids and solids. We will describe the perfect crystal monochromator back-scattering experimental set-up and the resulting instrumental function in energy and momentum space. We will then discuss the consequence of the above mentioned experimental characteristics, in particular for the application of the technique to phonon dispersion measurements in crystals, in comparison with triple axes inelastic neutron scattering and Raman experiments.

ABSTRACTThe intussusception is one of the most frequent causes of occlusive syndrome in infants and in children.1The mesenteric lymphadenopathy, wich is very rare post rotavirus vaccination, can cause intussusception,2-5especially in genetically predisposed individuals.6There is an association between intussusception and some classes of genotype.7-9Two infants aged 3 months, vaccinated against rotavirus. After about a week, one of the 2 identical infants presented inconsolable crying, vomiting, loose stools mixed with blood, and was diagnosed with bowel obstruction with intussusception. He was operated in urgency. After a few hours, his brother presented vomiting, and was admitted to our Hospital for suspected intussusception. The controls carried out have confirmed the presence of intussusception that was treated early, before the onset of severe symptoms. The incidence of post rotavirus vaccine intussusception is very low. The determining factor hypothetically might be linked to the presence of a genotype that exposes infants to a greater risk of developing mesenteric lymphadenitis and intussusception. In our case, the diagnosis of intussusception occurred in a twin, which allowed us to recognize early symptoms which accused the brother and schedule the surgery with less urgency. Our experience may want to sensitize families and pediatricians to report cases of intussusception given a theoretical familiar association. The study of the genotype could be decisive for or not to exclude the presence of a risk of invagination, thus avoiding vaccination.

In order to elucidate the origin of the interplay between charge density wave (CDW) and superconductivity in 1T-TaS2, we have synthesized powder samples of pure and C-intercalated 1T-CxTaS2 by means of a multi-anvil high-pressure synthesis method. We have found that single-phase samples are obtained in the 2-6 GPa range at 400 °C and for x=0-0.3. The structural, magnetic and transport properties of all samples have been investigated by means of neutron and x-ray diffraction, dc magnetization and dc electrical resistivity. For all x values including x=0, the data show that the CDW phase is suppressed concomitant to an abrupt onset of superconductivity, with Tc=3.2 K for x=0. The Tc value turns out to be weakly dependent on x, with a maximum Tc=3.8 K for x=0.2. This onset is accompanied by a crossover of magnetic behavior from paramagnetic Pauli-like to paramagnetic Curie-Weiss-like with effective moment  1.2 B/Ta, which suggests that a ionic picture is suitable for the superconducting phase, but not for the CDW phase. The analysis of the dependence of the a and c lattice parameters upon x as well as upon the synthesis conditions shows that the onset of superconductivity is mainly ascribed to unusual changes of the unit cell induced by the high-pressure synthesis. Specifically, the ex-situ lattice parameters exhibit a significantly larger c-axis parameter and a shrinking of the a-axis parameter stabilized by the high-pressure synthesis route. We argue that the above suppression of the CDW phase is induced by a broadening of the relevant 5d(t2g) band which stabilizes the metallic and superconducting phases. This scenario suggests that the strength of the electronic correlations are the main control parameter of the CDW-superconductivity competition in 1T-TaS2.

The study of phonon dispersion curves of materials under hydrostatic pressure provides important information such as the evolution of sound velocities, elastic constants, interatomic potentials, phase transition mechanisms, etc. Until very recently, coherent inelastic neutron scattering was the only spectroscopic technique, which allowed performing these types of studies up to typically 10 GPa. Today, inelastic X-ray scattering with meV energy resolution provides a complementary spectroscopic technique, where, using diamond anvil cell techniques, pressures beyond 100 GPa can be reached.

We investigated whether intervention with antioxidant vitamins C and E in enteral feeding influenced oxidative stress and clinical outcome in critically ill patients. Two-hundred sixteen patients expected to require at least 10 days of enteral feeding completed the study. One-hundred five patients received enteral feeding supplemented with antioxidants, and 111 control patients received an isocaloric formula. Plasma lipoperoxidation (by thiobarbituric acid reactive substances [TBARS] and prostaglandin F2aisoprostane levels), low-density lipoprotein (LDL) oxidizability, and LDL tocopherol content were determined at baseline and at the end of the 10-day period. The clinical 28-day outcome was also assessed. Plasma TBARS and isoprostanes were 5.33 ± 1.26 nM/mL and 312 ± 68 pg/mL, respectively, before treatment and 2.42 ± 0.61 nM/mL and 198± 42 pg/mL after intervention (p< .01 for both comparisons). Antioxidants improved LDL resistance to oxidative stress by approximately 30% (the lag time before treatment was 87 ± 23 minutes and was 118 ± 20 minutes after treatment; p< .04). There was a significantly reduced 28-day mortality after antioxidant intervention (45.7% in the antioxidant group and 67.5% in the regular-feeding group; p< .05). Isoprostanes may provide a sensitive biochemical marker for dose selection in studies involving antioxidants.

Kasabach-Merrit syndrome, the association of a vascular lesion and consumptive coagulopathy represent a diagnostic and therapeutic challenge to clinicians. We report a case of an infant with a large mass of the liver diagnosed at 25 weeks of amenorrhea that started to bleed at 33 weeks of gestational age. A male newborn, 33 GW, 3170 gr of weight, was admitted to the neonatal intensive care unit for severe consumption coagulopathy caused by hepatic mass prenatally diagnosed. At the admission the clinical conditions were severe and so we decided for surgical treatment. He was then operated on at 3 hours of life. The operation was a total excision of the tumor with a left-side hemihepatectomy. Macroscopically the tumor was brown, encapsulated, elastic in consistency. The weight was 200 gr and the diameter 9 cm. Histological examination revealed an infantile hemangioendothelioma of the liver. The infant received a pre and postoperatively supportive care with transfusions of fresh frozen plasma and red blood cells and infusion protein C i.v. To stop the activation of coagulopathy. The postoperative course was uneventful. At 6 months after surgery the patient had no evidence of residual tumor or further coagulopathy. In 1940, Kasabach and Merrit first described the association of a large vascular tumor and trombocytopenia and termed this Kasabach-Merrit syndrome. This is a potentially life-threatening condition, with mortality estimates ranging from 20 to 30% as a result of severe sepsis, coagulopathy, or invasion of vital organs. Treatment modality have included corticosteroids, interferon alfa 2a or 2b, vincristine, cyclophosphamide, ticlopidine, aspirin, amicar, radiation therapy, and surgical excision. In our case the treatment of this life-threatening condition was aggressive surgery at birth associated to medical treatment of coagulopathy. To our knownledge our patient is the younger one in literature who underwent surgery for this lesion.