Time-resolved structural dynamics of the out-of-equilibrium charge density wave phase transition in GdTe3.

We use ultrafast electron diffraction to study the out-of-equilibrium dynamics of the charge density wave (CDW) phase transition in GdTe3, a quasi-two-dimensional compound displaying a unidirectional CDW state. Experiments were conducted at different incident fluences and different initial sample temperatures below Tc. We find that following photo-excitation, the system undergoes a non-thermal ultrafast phase transition that occurs in out-of-equilibrium conditions. The intrinsic crystal temperature was estimated at each time delay from the atomic thermal motion, which affects each Bragg peak intensity via the Debye Waller factor. We find that the crystal temperature stabilizes with a 6 ps timescale in a quasi-equilibrium state at temperature Tq.e.. We then relate the recovery time of the CDW and its correlation lengths as a function of Tq.e.. The charge density wave is suppressed in less than a picosecond while its recovery time increases linearly with incident fluence and initial temperature. Our results highlight that the dynamics is strongly determined by the initial sample temperature. In addition, the transient CDW phase recently observed along the transverse direction in LaTe3 and CeTe3 is not observed in GdTe3.

Role of thermodynamics in the shape transformation of embedded metal nanoparticles induced by swift heavy-ion irradiation.

Swift heavy-ion irradiation of elemental metal nanoparticles (NPs) embedded in amorphous SiO(2) induces a spherical to rodlike shape transformation with the direction of NP elongation aligned to that of the incident ion. Large, once-spherical NPs become progressively more rodlike while small NPs below a critical diameter do not elongate but dissolve in the matrix. We examine this shape transformation for ten metals under a common irradiation condition to achieve mechanistic insight into the transformation process. Subtle differences are apparent including the saturation of the elongated NP width at a minimum sustainable, metal-specific value. Elongated NPs of lesser width are unstable and subject to vaporization. Furthermore, we demonstrate the elongation process is governed by the formation of a molten ion-track in amorphous SiO(2) such that upon saturation the elongated NP width never exceeds the molten ion-track diameter.

Ion-induced elongation of gold nanoparticles in silica by irradiation with Ag and Cu swift heavy ions: track radius and energy loss threshold.

Systematic investigations of the energy loss threshold above which the irradiation-induced elongation of spherical Au nanoparticles occurs are reported. Silica films containing Au nanoparticles with average diameters of 15-80 nm embedded within a single plane were irradiated with 12-54 MeV Ag and 10-45 MeV Cu ions at 300 K and at normal incidence. We demonstrate that the efficiency of the ion-induced nanoparticle elongation increases linearly with the electronic energy transferred per ion track length unit from the energetic ions to the silica film. Ion beam shaping occurs above a threshold value of the specific electronic energy transfer. Three relevant regions are identified with respect to the original size of the Au nanoparticles. For 15 and 30 nm diameter particles, elongation occurs for electronic stopping power larger than 3.5 keV nm(-1). For Au nanoparticles with 40-50 nm diameter an electronic stopping power above 5.5 keV nm(-1) is required for elongation to be observed. Elongation of Au nanoparticles with 80 nm diameter is observed for electronic stopping between ∼ 7-8 keV nm(-1). For all combinations of ions and energies, the ion track temperature profiles are calculated within the framework of the thermal spike model. The correlation between experimental results and simulated data indicates a thermal origin of the increase in the elongation rate with increasing the track diameter.

Is there a uniform basal endometrial gene expression profile during the implantation window in women who became pregnant in a subsequent ICSI cycle?

BACKGROUND: To understand which genes are really involved in the implantation process, we planned to study the gene basal expression profile during the window of implantation (WOI) of patients who became pregnant in a subsequent ICSI cycle. METHODS: Women attending their first ICSI cycle at ANDROS Day Surgery for severe male factor infertility were included in the study. An endometrial biopsy was performed during the WOI, in one of the last two cycles before the ICSI cycle. Forty-seven selected gene profiles were analyzed using Low Density Array technology. Only biopsies from women who subsequently became pregnant were evaluated, to exclude any bias regarding embryo viability and embryo transfer difficulties. RESULTS: Fifteen patients were included in the analysis as they became pregnant after ICSI procedure. Four of 47 selected genes were excluded from the analysis. Of the 43 genes analyzed, only 6 genes (VEGFA, PLA2G2A, ALPL, LIF, NNMT and STC1) showed a statistically uniform expression among patients who subsequently became pregnant. For all the other genes analyzed there were considerable differences in their expression levels amongst women who subsequently became pregnant. CONCLUSIONS: Our data suggest that very few genes, which change their expression level during the WOI, show a quantitative homogeneous expression in endometrially-receptive patients. In conclusion, in this study only six genes showed a homogeneous expression, and are probably involved in embryo implantation mechanisms.

C-reactive protein in patients on chronic hemodialysis with different techniques and different membranes.

In hemodialysis patients, C-reactive protein (CRP), an acute-phase reactant, is a sensitive and independent marker of malnutrition, anemia, and cardiovascular mortality. The aim of the present study was to evaluate CRP levels in plasma samples from long-term hemodialysis patients on different extracorporeal modalities and dialyzed with different membranes, at baseline and after 6 months. Two hundred and forty-seven patients were recruited in eight hospital-based centers. All patients had been on their dialytic modality for at least 3 months and were prospectively followed in their initial dialytic modality for 6 months. Patients were treated with conventional bicarbonate dialysis (N = 127) or hemodiafiltration (N = 120). Patients treated with conventional bicarbonate dialysis were dialyzed with different membranes: Cuprophane (N = 51), low-flux cellulose modified membrane (N = 37) and synthetic membranes (N = 39). Hemodiafiltration was performed in post-dilution mode with polysulfone (N = 66) and polyacrylonitrile (N = 54) membranes. Analysis of baseline CRP values in the clinically stable patients showed that an unexpectedly high proportion (47%) of the patients had CRP values higher than 5 mg/l (upper limit in normal subjects). The mean +/- S.D. CRP values were significantly higher (P < 0.05) in hemodiafiltration with infusion volumes < 10 l per session (14.6+/-3.1 mg/l) than in standard hemodialysis (5.1 +/- 2.1 mg/l) and hemodiafiltration with infusion volumes > 20 l per session (4.9 +/- 2.1 mg/l). These values did not significantly change after 6 months of follow-up. Concerning the membranes, the highest levels of CRP were observed in patients dialyzed with Cuprophane with a significant increase from 15.1 +/- 3.6 to 21.2 +/- 3.1 mg/l after 6 months (P < 0.05); a significant reduction of CRP levels was observed in patients dialyzed with polysulfone in the same follow-up period (from 13.5 +/- 2.9 to 8.1 +/- 2.4 mg/l; P < 0.05). The CRP increase following low volume HDF can be related to back-filtration of bacterial derived contaminants.; moreover, an important effect on CRP of the hemodialysis membrane is observed and new synthetic membranes can be used to decrease these levels.

Safety and effects on the lipid and C-reactive protein plasma concentration of the association of ezetimibe plus atorvastatin in renal transplant patients treated by cyclosporine-A: a pilot study.

Ezetimibe (E) is a new cholesterol adsorption inhibitor which prevents the adsorption of dietary and biliary cholesterol by binding to a recently described cholesterol transporter. This pilot study was performed to evaluate the safety and the low-density lipoprotein (LDL)-C and C-reactive protein lowering efficacy of atorvastatin (A) and of the association of A plus E in five renal transplant patients with hypercholesterolemia and mild renal functional impairment receiving cyclosporine-A (CsA). Patients received for three periods, each of 3 weeks, A at a dose of 20 mg/day; A at a dose of 10 mg/day and finally, A 10 mg plus E 10 mg daily. The medications were well-tolerated and no important clinical or laboratory (muscle enzyme, creatinine clearance and CsA concentration) abnormalities were observed throughout the study period. A alone lead to target LDL-C values only in two of five patients and did not significantly reduce the mean CRP values. The combination of E plus A produced the lowest lipid levels and significantly reduced CRP mean values and allowed all patients to attain target levels of LDL-C: total cholesterol decreased from 240 +/- 42 (mean +/- S.D.) to 171 +/- 34 mg/dl, LDL-C from 129 +/- 32 to 87 +/- 21 mg/dl, plasma triglycerides from 330 +/- 54 to 194 +/- 71 mg/dl and CRP from 6.2 +/- 1.9 to 3.9 +/- 2.4 mg/l (P < 0.05 for all). This pilot study suggests that the co-administration of E and A at 10 mg/day in renal transplant patients receiving CsA is well-tolerated and effective in reducing important cardiovascular risk factors.

[Graduated and constant compression of the lower extremities in the prevention of postoperative deep venous thrombosis and of pulmonary thromboembolism. Clinical trial]. / Compressione graduata e costante degli arti inferiori, nella profilassi delle flebotrombosi profonde e delle trombo-embolie polmonari post-operatorie. Sperimentazione clinica.

The authors report their experience with graded-pressure elastic hose (TED Stockings) for the prevention of deep venous thrombosis of the lower limbs and pulmonary embolism in high-risk, bedridden postoperative patients. The trial was designed according to a closed sequential program and gave positive, statistically significant results in terms of preventing pathology with this type of hose.

[Closed injuries of the liver]. / Traumi chiusi del fegato.

The authors shortly illustrate the etiopathogenesis, symptomatology, diagnosis, complications and treatment of liver blunt trauma. They describe their experience of 33 hepatic lesions out of 210 abdominal blunt trauma with a 12,1% mortality, and emphasize the usefulness of the laparoscopic investigation in the precocious diagnosis of such disease.

[Papilloma of the gallbladder]. / Papilloma della colecisti.

Gall-bladder papilloma, although rare to be found, should be considered as a precancerous lesion, the sole treatment of which is the surgical one. The authors, starting from three cases of such pathology, they had the opportunity to observe, deal with histogenesis, symptomatology and treatment of such disease, and indicate the possibility for a careful diagnosis through the modern diagnostical means.

[Our experience with closed injuries of the pancreas]. / La nostra esperienza sui traumi chiusi del pancreas.

The authors illustrate the types of anatomo-pathologic lesions, symptomatology, diagnostical means and treatment of pancreatic blunt trauma. They describe their experience about 4 cases (1,94%) of pancreatic trauma out of 210 abdominal blunt trauma. They, moreover, emphasize the usefulness of laparoscopy as an investigating mean offering a sure diagnostical reliability.

[Spontaneous hemoperitoneum]. / Emoperitoneo spontaneo.

The authors report their experience of 11 cases of hemoperitoneum due to hemorrhagic endoabdominal neoformation, diagnosed through laparoscopy, and the diagnosis of which was confirmed by the biopsy under the sight. They describe the casuistry observed: 4 hepatic neoplasms (11,9%); 4 ovary neoplasmus (12,1%); 1 neuroblastoma (10%); 2 ovary endometriosic cysts (16,6%). They, at last, emphasize the usefulness of laparoscopy as an investigating mean offering a sure diagnostical reliability.

[Bladder hernia]. / Le ernie della vescica.

A case of bladder hernia in a 61 years old patient affected by benign prostatic hypertrophy is presented. Pre-operative diagnosis was made by cystography. After an adenomiomectomy of the prostate, the patient underwent the resection of the herniated bladder which gave the bladder its normal shape with only a slight reduction of its capacity. Inguino-scrotal bladder hernias are very rare; recognized predisponing factors are weakening of muscular and connective structures of the inguinal canal, and bladder hypotonia secondary to urethro-prostatic obstruction. These hernias, according to the anatomical position of the hernial sac, bladder and peritoneum, are classified in paraperitoneal (most frequent), intraperitoneal and extraperitoneal. The typical symptom of this disease is the two-stage micturition: the patient after a first spontaneous voiding, presses the mass and voids again. Other than cystography, useful diagnostic means are urography and cystoscopy which may confirm the diagnosis and rule out associated urinary disease. The treatment consists of either simple reduction of the bladder hernia, if the hernia is small, or resection of the herniated portion of the bladder, if the hernia is large or is associated with other diseases (e.g. tumors). Bladder resection is then followed by closure of the bladder wall in two layers and by inguinal hernia repair.

SAXS investigations of the morphology of swift heavy ion tracks in α-quartz.

The morphology of swift heavy ion tracks in crystalline α-quartz was investigated using small angle x-ray scattering (SAXS), molecular dynamics (MD) simulations and transmission electron microscopy. Tracks were generated by irradiation with heavy ions with energies between 27 MeV and 2.2 GeV. The analysis of the SAXS data indicates a density change of the tracks of ~2 ± 1% compared to the surrounding quartz matrix for all irradiation conditions. The track radii only show a weak dependence on the electronic energy loss at values above 17 keV nm(-1), in contrast to values previously reported from Rutherford backscattering spectrometry measurements and expectations from the inelastic thermal spike model. The MD simulations are in good agreement at low energy losses, yet predict larger radii than SAXS at high ion energies. The observed discrepancies are discussed with respect to the formation of a defective halo around an amorphous track core, the existence of high stresses and/or the possible presence of a boiling phase in quartz predicted by the inelastic thermal spike model.