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1.
Science ; 361(6398): 162-165, 2018 07 13.
Article in English | MEDLINE | ID: mdl-30002250

ABSTRACT

Understanding magnetic phases in quantum mechanical systems is one of the essential goals in condensed matter physics, and the advent of prototype quantum simulation hardware has provided new tools for experimentally probing such systems. We report on the experimental realization of a quantum simulation of interacting Ising spins on three-dimensional cubic lattices up to dimensions 8 × 8 × 8 on a D-Wave processor (D-Wave Systems, Burnaby, Canada). The ability to control and read out the state of individual spins provides direct access to several order parameters, which we used to determine the lattice's magnetic phases as well as critical disorder and one of its universal exponents. By tuning the degree of disorder and effective transverse magnetic field, we observed phase transitions between a paramagnetic, an antiferromagnetic, and a spin-glass phase.

2.
Minerva Pediatr ; 65(4): 361-70, 2013 Aug.
Article in Italian | MEDLINE | ID: mdl-24051969

ABSTRACT

AIM: The use of complementary and alternative medicine (CAM) has not been widely studied among children in Italy. ISTAT-2005 survey showed a prevalence of 10% of children treated with CAM. Most of other contributes were related to Northern populations. The aim of our study was to analyse the rate of CAM use in the children living in Piemonte compared to the children living in Calabria. METHODS: Data were collected through a structural questionnaire administered to the parents of the children admitted to the pediatric department of the Regional Hospital in Torino, Catanzaro and Cosenza. The questionnaire included questions about the use of CAM and the demographic characteristics of the parents and the child responding. RESULTS: For the study 1156 questionnaires were distributed in total and 1,136 were analyzed. Overall the response rate was more than 98%. In Turin 43% of the children were treated also with CAM, in Cosenza and in Catanzaro 38% and 21%, respectively. The parents who used CAM for their children were more aged and with a higher education. In Turin homeopathy was used more, in the south of Italy phytotherapy was preferred. More acute respiratory diseases were the most frequent diseases treated with CAM. In the majority of cases CAM were prescribed by pediatricians. Most of the people preferred CAM for less side effects and the majority of them declared to be satisfied. Furthermore, this survey shows that parents use CAM as complementary rather than alternative to medicine. CONCLUSION: Our study remarks as the use of CAM is dramatically increased among the Italian children in the last years as well as in other countries. Pediatricians need to improve their knowledge about CAM in order to better manage parental attitude.


Subject(s)
Complementary Therapies/statistics & numerical data , Child , Child, Preschool , Female , Humans , Infant , Italy , Male , Parents , Surveys and Questionnaires
3.
Minerva Pediatr ; 65(4): 427-45, 2013 Aug.
Article in Italian | MEDLINE | ID: mdl-24051976

ABSTRACT

Patients without spleen or with diminished splenic function are at high risk (10-50 times higher than in normal population) of developing life-threatening infections (OPSI). Mortality from OPSI is estimated at 50 to 80% of cases. More frequent causative agents are encapsulated bacteria: Streptococcus Pneumoniae, Haemophilus influenzae type b and Neisseria Meningitidis. The risk of OPSI can be reduced by immunizing patients against these pathogens and by prescribing antibiotic prophylaxis. Continuous antibiotic prophylactic for 2-5 years after splenectomy (longer periods might expose the patients to the risk of antibiotic resistance) with penicillin or amoxicillin/clavulanate acid is mandatory. Asplenic individuals should take empirical antibiotic therapy - so called "self-treatment" - and immediate medical consultation in presence of febrile illness. All patients and their parents should be carefully educated about the risk of infections in order to obtain a good long-term compliance with these recommendations.


Subject(s)
Bacterial Infections/prevention & control , Postoperative Complications/prevention & control , Spleen/physiopathology , Splenectomy , Antibiotic Prophylaxis , Bacterial Infections/diagnosis , Bacterial Infections/etiology , Bacterial Infections/microbiology , Family , Humans , Patient Compliance , Patient Education as Topic , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Postoperative Complications/microbiology , Splenectomy/adverse effects
4.
Nat Commun ; 4: 1903, 2013.
Article in English | MEDLINE | ID: mdl-23695697

ABSTRACT

Efforts to develop useful quantum computers have been blocked primarily by environmental noise. Quantum annealing is a scheme of quantum computation that is predicted to be more robust against noise, because despite the thermal environment mixing the system's state in the energy basis, the system partially retains coherence in the computational basis, and hence is able to establish well-defined eigenstates. Here we examine the environment's effect on quantum annealing using 16 qubits of a superconducting quantum processor. For a problem instance with an isolated small-gap anticrossing between the lowest two energy levels, we experimentally demonstrate that, even with annealing times eight orders of magnitude longer than the predicted single-qubit decoherence time, the probabilities of performing a successful computation are similar to those expected for a fully coherent system. Moreover, for the problem studied, we show that quantum annealing can take advantage of a thermal environment to achieve a speedup factor of up to 1,000 over a closed system.

5.
Phys Rev Lett ; 104(17): 177004, 2010 Apr 30.
Article in English | MEDLINE | ID: mdl-20482130

ABSTRACT

We demonstrate coherent tunable coupling between a superconducting phase qubit and a lumped-element resonator. The coupling strength is mediated by a flux-biased rf SQUID operated in the nonhysteretic regime. By tuning the applied flux bias to the rf SQUID we change the effective mutual inductance, and thus the coupling energy, between the phase qubit and resonator. We verify the modulation of coupling strength from 0 to 100 MHz by observing modulation in the size of the splitting in the phase qubit's spectroscopy, as well as coherently by observing modulation in the vacuum Rabi oscillation frequency when on resonance. The measured spectroscopic splittings and vacuum Rabi oscillations agree well with theoretical predictions.

6.
Ultrasound Obstet Gynecol ; 24(1): 23-9, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15229912

ABSTRACT

OBJECTIVE: To compare maternal hemodynamics in women whose fetuses are small-for-gestational age (SGA) with those in women with fetal growth restriction (FGR) before manifestation of the clinical disease. METHODS: Thirty-five normotensive pregnant women with fetal abdominal circumference < 10th centile, normal fetal anatomy and normal umbilical artery pulsatility index (PI) underwent maternal echocardiographic examinations between 27 and 30 weeks of gestation. Pregnancies were followed until delivery and fetuses were retrospectively classified as either SGA or FGR and the maternal hemodynamic data were compared. RESULTS: Nineteen SGA and 16 FGR patients were retrospectively identified after delivery. Heart rate, stroke volume, cardiac output, left atrial function and left ventricular mass index were higher, while mean blood pressure and total vascular resistance were lower in the SGA group compared with the FGR group. A significant inverse linear correlation was found between total vascular resistance and weight centile (r = 0.83; P < 0.0001). CONCLUSIONS: Mothers of SGA fetuses show hemodynamic features similar to those with physiological pregnancies suggesting that their fetuses are likely to be constitutionally small and not pathologically growth-restricted.


Subject(s)
Fetal Growth Retardation , Pregnancy Complications, Hematologic/diagnostic imaging , Adult , Birth Weight , Case-Control Studies , Echocardiography , Female , Hemodynamics , Humans , Infant, Newborn , Infant, Small for Gestational Age , Linear Models , Pregnancy , Pregnancy Trimester, Third , Retrospective Studies , Ultrasonography, Prenatal
7.
Ultrasound Obstet Gynecol ; 22(6): 591-7, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14689531

ABSTRACT

OBJECTIVE: To determine reference values of fetal subcutaneous tissue thickness (SCTT) throughout gestation in a healthy population and to compare them with those from a population of pregnant women with gestational diabetes under standard therapy. METHODS: Three hundred and three women recruited from a high-risk pregnancy clinic were classified as being healthy (n = 218) or as having gestational diabetes (n = 85) on the basis of a negative or positive oral glucose tolerance test, respectively. They were enrolled into the cross-sectional study at 20 weeks' gestation. Ultrasound examinations were performed approximately every 3 weeks until delivery at term. The mid-arm fat mass and lean mass (MAFM, MALM), the mid-thigh fat mass and lean mass (MTFM, MTLM), the abdominal fat mass (AFM) and the subscapular fat mass (SSFM) were evaluated. Time-specific reference ranges were constructed from the 218 healthy women and a conventional Student's t-test was performed to compare SCTT values between the two study groups throughout gestation. RESULTS: Normal ranges, including 5th, 50th and 95th centiles of the distribution, were generated for each SCTT parameter obtained in each of the two groups of women. Significant differences were found between the two study groups at 37-40 weeks' gestation for MTFM, at 20-22 and 26-28 weeks for MTLM, at 31-34 and 35-37 weeks for MAFM, at 26-28 and 38-40 weeks for SSFM, and at 39-40 weeks for AFM, the mean residual values always being greater in gestational diabetic women than they were in the group of healthy pregnant women. CONCLUSIONS: We provide gestational age-specific reference values for fetal SCTT. Fetal fat mass values, particularly in late gestation, are greater in women with gestational diabetes compared with healthy women. The reference values may have a role in assessing the influence of maternal metabolic control on fetal state.


Subject(s)
Diabetes, Gestational/diagnostic imaging , Embryonic and Fetal Development , Subcutaneous Tissue/diagnostic imaging , Adult , Cross-Sectional Studies , Diabetes, Gestational/diagnosis , Female , Gestational Age , Glucose Tolerance Test , Humans , Pregnancy , Reference Values , Reproducibility of Results , Subcutaneous Tissue/anatomy & histology , Subcutaneous Tissue/embryology , Ultrasonography, Prenatal/methods
8.
Acta Diabetol ; 40 Suppl 1: S216-21, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14618477

ABSTRACT

We assessed total body water (TBW) content and cardiac function in 25 normotensive (N) and 22 gestational hypertensive (GH) women matched for age, gestational age, and prepregnancy body mass index (BMI) during the third trimester of gestation. Patients underwent maternal echocardiography, bioelectrical impedance analysis (BIA), and hematocrit (Hct %) evaluation. The TBW:Hct ratio (water balance index, WBI) was calculated. Hct was significantly lower in N vs. GH women (31.9+/-2.2% vs. 36.2+/-2.5; p<0.001). There was no difference in TBW between the two groups. WBI was higher in N vs. GH women (1.35+/-0.20 l.kg(-1) x m(-2) vs. 1.19+/-0.18; p<0.001). N subjects showed a higher stroke volume than GH patients (78.0+/-9.7 ml vs. 67.9+/-10.2; p=0.001). Atrial function was higher in N vs. GH women (left atrial fractional area change 57.4+/-5.1% vs. 42.5+/-7.5; p<0.001). A correlation was found between stroke volume and WBI ( r=0.93, p<0.0001). Maternal cardiac function and WBI are strongly related and might help in understanding the mechanisms of adaptation in normal and hypertensive pregnancy.


Subject(s)
Heart/physiology , Hypertension/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Pregnancy/physiology , Adult , Atrial Function, Left , Body Water/physiology , Echocardiography, Three-Dimensional/methods , Electric Impedance , Female , Heart/physiopathology , Heart Function Tests , Humans , Hypertension/diagnostic imaging , Parity , Pregnancy Complications, Cardiovascular/diagnostic imaging , Reference Values , Stroke Volume , Ventricular Function, Left
9.
Acta Diabetol ; 40 Suppl 1: S225-32, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14618479

ABSTRACT

Maternal body composition undergoes a deep adaptative change during the course of pregnancy. Fat mass, fat-free mass, and total body water (TBW) increase in different ways and their effects on pregnancy outcome represent a field of major interest in perinatal medicine. The aim of this study was to evaluate the changes in maternal body composition [maternal weight, TBW, intracellular water (ICW) and extracellular water (ECW)] during healthy pregnancy by using bioimpedance analysis (BIA). A total of 170 healthy pregnant women, aged 22-44 years, volunteered to participate in our study. The BIA measurements were carried out with a Tefal BIA scale determining resistance and reactance. Lukaski's multiple-regression equation was used to estimate TBW and ICW and ECW were computed using the prediction formula of Segal. The evaluations were performed at 10-38 weeks' gestation, every 3-4 weeks, and hematocrit was determined at every time interval. Analysis of variance and multiple comparisons of Bonferroni were performed to compare variables among the different study intervals. Second-order polynomial interpolation was used to obtain percentile values for each bioimpedance parameter. Percentile bioimpedance values of the healthy population are provided at each study time, by showing the mean value and the 5th, 25th, 75th, 95th percentiles. Moreover, normal reference ranges for TBW are provided for each gestational age, in relation to maternal weight gain. Reactance, TBW, and ICW enhance slightly during the course of gestation. Tetrapolar BIA could be an easy and practical tool for evaluating changes of maternal body components during pregnancy. It could also provide indirect proof of the normal hemodilution occurring in normal pregnancies. Moreover, fat mass deposition, and not only fluid retention, seems to be responsible for the mother's gestational weight gain, since reactance is an indirect parameter in estimating fat mass amount.


Subject(s)
Body Composition/physiology , Pregnancy/physiology , Adipose Tissue/anatomy & histology , Body Water/physiology , Body Weight/physiology , Electric Impedance , Female , Gestational Age , Humans , Reference Values , Weight Gain/physiology
10.
Ultrasound Obstet Gynecol ; 20(5): 452-7, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12423481

ABSTRACT

OBJECTIVE: To explore maternal cardiac function through an echocardiographic evaluation, in a group of nulliparous patients with intrauterine fetal growth restriction during the third trimester of pregnancy. METHODS: Twenty-one consecutive nulliparous pregnant women who had fetuses with intrauterine growth restriction (IUGR) and abnormal umbilical artery Doppler pulsatility index (PI) underwent maternal echocardiographic examination during the third trimester of gestation. The data were then compared with those obtained from 21 normal nulliparous women who had fetuses with an estimated fetal weight > 10th percentile and a normal umbilical artery Doppler PI who were considered as the control group. RESULTS: Heart rate was slightly lower in the IUGR group, whereas blood pressure and total vascular resistance were higher compared with the control subjects. End-diastolic volume, stroke volume and cardiac output were lower in the IUGR patients compared with normal patients. The IUGR group had smaller left atrial maximal dimensions and greater left atrial minimal areas compared with the control subjects. Left atrial function was depressed in the IUGR group. A smaller left ventricular mass was present in the IUGR patients compared with the control subjects. Isovolumetric relaxation time (IVRT) was prolonged in the IUGR patients compared with the controls. CONCLUSIONS: The absence of a 'correct' maternal cardiovascular compensatory response to abnormal trophoblastic invasion, might be one of the factors that slowly determine the conditions of reduced placental perfusion and eventually of the development of fetal growth restriction.


Subject(s)
Fetal Growth Retardation/physiopathology , Heart Diseases/physiopathology , Pregnancy Complications, Cardiovascular/physiopathology , Adult , Blood Pressure/physiology , Case-Control Studies , Diastole , Echocardiography/methods , Female , Fetal Growth Retardation/pathology , Heart Atria , Heart Diseases/pathology , Heart Rate/physiology , Heart Ventricles , Humans , Pregnancy , Pregnancy Complications, Cardiovascular/pathology , Pregnancy Outcome , Pregnancy Trimester, Third , Stroke Volume/physiology , Vascular Resistance/physiology , Ventricular Function, Left/physiology
12.
AJNR Am J Neuroradiol ; 17(4): 749-54, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8730196

ABSTRACT

PURPOSE: To estimate the prevalence of abnormal ocular enhancement in children with Sturge-Weber syndrome as detected with MR imaging and CT and to correlate this with the clinical, fundoscopic, and intracranial imaging findings. METHODS: Fifteen children, 4 years old or younger, with Sturge-Weber syndrome were examined with enhanced CT and MR imaging. Eleven children had unilateral intracranial involvement and 4 had bilateral involvement, for a total of 19 abnormal hemispheres and related orbits. The presence of ocular enhancement was compared with the fundoscopic findings independently. Ocular enhancement was correlated with the extent of leptomeningeal disease, the severity of the cutaneous lesion, and the presence of glaucoma by the calculation of likelihood ratios and 95% confidence limits. RESULTS: Seven of the 15 patients had abnormal ocular enhancement, which was present in 10 (53%) of the eyes associated with the 19 abnormal hemispheres. MR imaging showed choroidal hemangioma in 7 of 8 patients in whom hemangiomas were shown at fundoscopy. The likelihood of ocular enhancement was increased with the presence of bilateral disease, extensive facial nevi, and glaucoma; there was no significant correlation with the extent of hemispheric involvement. CONCLUSION: Both enhanced MR imaging and CT can show diffuse choroidal hemangioma in patients with Sturge-Weber syndrome. However, MR imaging is more sensitive and is recommended to aid in the detection of abnormalities with preventable late complications.


Subject(s)
Brain/pathology , Eye/pathology , Magnetic Resonance Imaging , Sturge-Weber Syndrome/diagnosis , Tomography, X-Ray Computed , Child, Preschool , Choroid Neoplasms/diagnosis , Diagnosis, Differential , Female , Follow-Up Studies , Fundus Oculi , Hemangioma/diagnosis , Humans , Infant , Male
13.
J Biol Chem ; 266(16): 10461-9, 1991 Jun 05.
Article in English | MEDLINE | ID: mdl-2037593

ABSTRACT

By screening approximately 10(6) plaques in a wheat DNA library with a "full-length" germin cDNA probe, two genomic clones were detected. When digested with EcoRI, one clone yielded a 2.8-kilobase pair fragment (gf-2.8) and the other yielded a 3.8-kilobase pair fragment (gf-3.8). By nucleotide sequencing, each of gf-2.8 and gf-3.8 was found to encode a complete sequence for germin and germin mRNA, and to contain appreciable amounts of 5'- and 3'-flanking sequences. The "cap" site in gf-2.8 was determined by primer extension and the corresponding site in gf-3.8 was deduced by analogy. The mRNA coding sequences in gf-2.8 and gf-3.8 are intronless and 87% homologous with one another. The 5'-flanking regions in gf-2.8 and gf-3.8 contain recognizable sites of what are probably cis-acting elements but there is otherwise little if any significant similarity between them. In addition to putative TATA and CAAT boxes in the 5'-flanking regions of gf-2.8 and gf-3.8, there are AT-rich inverted-repeats, GC boxes, long purine-rich sequences, two 19-base pair direct-repeat sequences in gf-2.8, and a remarkably long (200-base pair) inverted-repeat sequence (approximately 90% homology) in gf-3.8. An 8% difference between the mature-protein coding regions in gf-2.8 and gf-3.8 is reflected by a corresponding 7% difference between the corresponding 201-residue proteins. Most significantly, the same 8% difference between the mature-protein coding regions in gf-2.8 and gf-3.8 is allied with no change whatever in a central part (61-151) of the encoded polypeptide sequences. It seems likely that this central, strongly conserved core in the germins is of first importance in the biochemical involvements of the proteins. When an equivalence is assumed between like amino acids, the gf-2.8 and gf-3.8 germins show significant (approximately 44%) similarity to spherulins 1a and 1b of Physarum polycephalum, a similarity that increases to approximately 50% in the conserved core of germin. Near the middle (87-96) of the conserved core in the germins is a rare PH(I/T)HPRATEI decapeptide sequence which is shared by spherulins (1a and 1b) and germins (gf-2.8 and gf-3.8). These similarities are discussed in the context of evidence which can be interpreted to suggest that the biochemistry of germins and spherulins is involved with cellular, perhaps cell-wall responses to desiccation, hydration, and osmotic stress.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Glycoproteins/genetics , Plant Proteins/genetics , Triticum/genetics , Amino Acid Sequence , Autoradiography , Base Sequence , Coccidioidin/genetics , DNA/genetics , DNA Probes , Fungal Proteins/genetics , Molecular Sequence Data , Ploidies , RNA, Messenger/genetics , Restriction Mapping
14.
Radiology ; 116(02): 413-4, 1975 Aug.
Article in English | MEDLINE | ID: mdl-1153746

ABSTRACT

A white male teenager with carcinoma of the breast had received radiation therapy for an asymptomatic enlarged thymus on the second, fourth and seventh days of life. The dose delivered to the infant breasts, the latent period, and the unusually young age of the patient suggest that the malignancy was related to the course of radiotherapy.


Subject(s)
Adenocarcinoma/etiology , Breast Neoplasms/etiology , Infant, Newborn, Diseases/radiotherapy , Radiotherapy/adverse effects , Thymus Hyperplasia/radiotherapy , Adolescent , Humans , Infant, Newborn , Male , Radiotherapy Dosage
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