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New simultaneous X-ray and radio observations of the archetypal mode-switching pulsar PSR B0943+10 have been carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in November 2014. They allowed us to better constrain the X-ray spectral and variability properties of this pulsar and to detect, for the first time, the X-ray pulsations also during the X-ray-fainter mode. The combined timing and spectral analysis indicates that unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap are present during both radio modes and vary in a correlated way.
Brain abscess is uncommon in paediatric population, but of clinical importance because of significant long-term morbidity and mortality. In this multicentre study, promoted by the Italian Society for Paediatric Infectious Diseases, we retrospectively collected patients aged 0–18 years, with a diagnosis of ‘brain abscess’. Seventy-nine children were included; the median age was 8·75 years. As predisposing factor, 44 children had preceding infections. The Gram-positive cocci were mostly isolated (27 cases). Sixty (76%) children underwent a surgical intervention. Intravenous antibiotic therapy was administered in all patients, then switched to oral treatment. Clinical sequelae were recorded in 31 (39·2%) children. Twenty-one of them had a single sequela, of which, the most represented, was epilepsy in nine of them. This study focus the attention on the need to have standardized national guidelines or adequate recommendations on type and duration of antibiotic treatment.
In recent years, a revolution in astronomical position measurements has been taking place with the advent of modern space techniques. These new techniques, which supplement the traditional astrometric measurements, include laser ranging to the moon and artificial satellites, very-long-baseline interferometry (VLBI) of galactic and extra-galactic radio sources and spacecraft, radio tracking of satellites, and radar-ranging and spacecraft tracking during planetary encounters. Impressive accuracies have been achieved and further improvements are forthcoming. Each technique can be expected to establish its own reference frame which is derived from observations of a particular class of objects. The celestial and terrestrial coordinate systems are related through adopted constants and definitions. Contemporary astronomy has led to the development of three principal celestial coordinate systems: the optical frame (FK4/FK5) based on positions of galactic stars; the planetary/lunar ephemeris frame based on the major celestial bodies of the solar system; and the radio frame constructed from observations of extragalactic radio sources (quasars). Each frame is rotated with respect to others; furthermore, the optical frame offset is time variable. It is important that all frames be interconnected and unified. The optical frame is being connected to the radio frame by VLBI observations of radio emitting stars. The radio frame is being tied to the ephemeris frame in several ways – one is via differential VLBI measurements between quasars and planet-orbiting spacecraft.
We present a nano-patterning process for semiconducting polymeric composites that could potentially be utilized for the development of polymer-based data storage devices. Nano-patterning (writing) operates on the basis of the mechanical interaction between the electrically unbiased tip of an atomic force microscope and the surface of polymeric composite films. Via friction forces, the tip/sample interaction produces a local increase of molecular disorder in the polymer matrix, inducing a localized lowering in the conductivity of the organic semiconductor. Herein we suggest a figure of merit for quantifying the efficiency of pattern formation and we address the dependence of the writing process on the thermal annealing temperature of the composite film. Control experiments on composite films deposited on substrates with different roughness suggest that the writing effect is invariant to the roughness of the substrate. The potential storage density of the writing process depends on the tip curvature.
The morphology of the sperm head has often been correlated with the outcome of in vitro fertilization, and has been shown to be the sole parameter in semen of value in predicting the success of intracytoplasmic sperm injection and intracytoplasmic morphologically selected sperm injection.
In this paper, we have studied whether digital holographic microscopy (DHM) may be useful to obtain quantitative data on human sperm head structure and compared this technique with high-power digitally enhanced Nomarski optics. The main advantage of digital holography is that high-resolution three-dimensional quantitative sample imaging may be automatically produced by numerical refocusing of a two-dimensional image at different object planes without any mechanical scanning. We show that DHM generates useful information on the dimensions and structure of human sperm, not revealed by conventional phase-contrast microscopy, in particular the volume of vacuoles, and suggest its use as an additional prognostic tool in assisted reproduction technology.
We report on the long term X-ray monitoring with Swift, RXTE, Suzaku, Chandra, and XMM-Newton of the outburst of the newly discovered magnetar Swift J1822.3–1606 (SGR 1822-1606), from the first observations soon after the detection of the short X-ray bursts which led to its discovery (July 2011), through the first stages of its outburst decay (April 2012). Our X-ray timing analysis finds the source rotating with a period of P = 8.43772016(2) s and a period derivative Ṗ = 8.3(2) × 10−14 ss−1, which entails an inferred dipolar surface magnetic field of B ≃ 2.7 × 1013 G at the equator. This measurement makes Swift J1822.3–1606 the second lowest magnetic field magnetar (after SGR 0418+5729; Rea et al. 2010). Following the flux and spectral evolution from the beginning of the outburst, we find that the flux decreased by about an order of magnitude, with a subtle softening of the spectrum, both typical of the outburst decay of magnetars. By modeling the secular thermal evolution of Swift J1822.3–1606, we find that the observed timing properties of the source, as well as its quiescent X-ray luminosity, can be reproduced if it was born with a poloidal and crustal toroidal fields of Bp ~ 1.5 × 1014 G and Btor ~ 7 × 1014 G, respectively, and if its current age is ~550 kyr (Rea et al. 2012).
Lay persons can learn cardiopulmonary resuscitation (CPR) with the instructors' method, and by self-training with the use of manikins. LSFA includes airway control (head-tilt, jaw thrust), mouth-to-mouth ventilation, control of external bleeding by direct compression and elevation, positioning for coma (stable side position) and shock (horizontal, legs up), and extrication from a wreck (rescue pull). LSFA so far has not included chest compressions for cardiac arrest. LSFA capability by bystanders who would treat injured victims in mass disasters might be the most important component to consider for disaster response. A LSFA self-training system, including a manual which coaches skill practice on one another, and an attractive first aid kit (A. Laerdal) was found effective in a study carried out in Norway. The present controlled study was to compare two self-training systems (designed by A. Laerdal et al), one with and one without the use of manikins, with the presently prevalent instructors' method and an untrained control group. The trainees were high school students in a typical community in Indiana PA, USA. The study was carried out in 1978–1979.
Cryopreservation of gametes is an important tool in assisted reproduction programmes; long-term storage of oocytes or spermatozoa is necessary when in vitro fertilization (IVF) or artificial insemination is to be performed at a future date. Cryopreservation of epididymal spermatozoa offers a potential tool for rescuing genetic material from males of endangered populations. The objectives of this work were to: (1) examine sperm motility, viability, abnormality and acrosome integrity of frozen–thawed domestic cat epididymal spermatozoa; and (2) evaluate the same cryopreservation method on wild feline spermatozoa, needed to preserve their genetic resources. Epididymides were collected from 20 domestic cats during routine neutering procedure and from two wild felines at autopsy. The sperm samples, diluted with 4% glycerol/Tris/egg yolk, were loaded into 0.25 ml mini-straws, exposed to nitrogen vapour and stored in liquid nitrogen. After 4 weeks, samples were thawed and re-evaluated. The quality of each fresh and frozen–thawed sperm sample was tested by determining the motility (54.7 ± 11.3% and 32 ± 13.1% respectively for cat spermatozoa; 38.3 ± 18.7% and 21.5 ± 16.8% respectively for tiger spermatozoa), viability (74.3 ± 8.6% and 45.2 ± 9.4% respectively for cat spermatozoa; 42.4 ± 14.5% and 33.5 ± 12.9% respectively for wild felid spermatozoa), morphology and acrosomal status. The present study showed that feline epididymal spermatozoa can be frozen in egg-yolk extender with 4.0% glycerol in 0.25 ml straws. The procedure used in the present study for epididymal cat sperm cryopreservation may be applied to bank the genetic resources of wild felid species.
To evaluate the use of remifentanil–propofol administered as target-controlled infusion during awake fibreoptic intubation for anticipated difficult tracheal intubation in acromegalic patients.
In all, 20 consecutive acromegalic patients underwent elective endonasal endoscopic transsphenoidal pituitary surgery. After premedication with midazolam 0.03 mg kg−1, initially a target-controlled infusion of remifentanil 1.0 ng mL−1 and propofol 1.5 μg mL−1 was started. The fibreoptic intubation was performed by the same physician experienced with the fibreoptic technique. During the fibreoptic procedure the target concentrations of remifentanil and propofol ranged between 1.0 and 5.0 ng mL−1, and between 1.5 and 3.5 μg mL−1, respectively. Changes in heart rate and mean arterial pressure were recorded during airway manipulation, during tracheal intubation, and at 1 and 3 min after. On the first postoperative day, patient recall and level of discomfort during fibreoptic intubation were evaluated.
Endotracheal intubation was efficaciously and quickly secured in all patients. A significant increase in mean arterial pressure and heart rate was recorded only during tracheal intubation (P < 0.05). Oxygenation was sufficient and no bradypnea or apnoea was recorded. All patients later described their anaesthetic experience as satisfactory. During fibreoptic intubation, remifentanil (ng mL−1) and propofol (μg mL−1) mean effect-site concentrations were 3.2 ± 0.3 and 2.0 ± 1.0, respectively.
Remifentanil and propofol target-controlled infusion provided satisfactory conscious sedation allowing for successful oral fibreoptic intubation in acromegalic patients with no recall.
Background and objective: Reducing postoperative mechanical ventilation in patients undergoing liver transplantation may have clinical and organizational advantages. On the basis of our experience, we here evaluate the possibility of practising immediate tracheal extubation in the operating theatre. Methods: In this prospective study, patients consecutively undergoing liver transplantation between 1 June 1999 and 31 May 2004 were extubated in the operating theatre at the end of surgery on the basis of standardized and universally accepted criteria, under conditions of haemodynamic and metabolic stability. Results: Two hundred and seven of the 354 patients (58.5%) were extubated immediately after the completion of the surgical procedure (mean time between end of surgery and extubation: 0.4 ± 1.4 min); two were re-intubated. In the last of the 5 yr of the study, the percentage of immediate extubations increased to 82.5%. During the study period, there was a progressive increase in the number of immediate extubations per individual member of the team of anaesthetists. The pre-transplant Child-Pugh severity of the underlying liver disease did not predict rapid extubation, but the Model for End-stage Liver Disease score of <11 did (receiver operator characteristic area under the curve = 0.61; P < 0.05). Conclusions: Immediate extubation after liver transplantation is possible in a substantial percentage of cases; confidence, habit and a spirit of emulation are decisive factors in encouraging anaesthetists to extend this practice to the largest possible number of patients. A successful immediate extubation may be an important indicator of perioperative quality of care in liver transplantation.
The present study is the second part of a program of characterization of the site surrounding the SoGIN Garigliano Nuclear Power Plant (Southern Italy), which is currently involved in decommissioning activities. In the first phase of the project the reference groups of the population were established on the basis of a socio-economical study of the site; the radiological doses due to the assumed radioactive releases during the decommissioning phase were calculated by using climatological, hydrological, geomorphological parameters of the studied area; transport and diffusion specific models of some radionuclides in the environment were implemented to calculate the dose using specific evaluation software. The second part of the study focuses on the project of an environmental network designed in order to ensure the continuous monitoring of the radioactive release concentrations. All the criteria for the choice of grid points, by considering specific paths of transfer in the environment, were established for all the environmental compartments. A field campaign was carried out aiming to assess the “zero level" due to the natural radioactivity and past anthropogenic activities.
SPARC and SPARX are two different initiatives toward an Italian
Free Electron Laser (FEL) source
operating in the Self Amplified Spontaneous
Emission (SASE) mode, in which several national
research institutions are involved. SPARC is a high gain FEL project
devoted to provide a source of visible and VUV radiation while
exploiting the SASE mechanism. An advanced Photo-Injector system,
emittance compensating RF-gun plus a 150 MeV Linac, will inject a high
quality e-beam into the undulator to generate high brilliance FEL
radiation in the visible region at the fundamental wavelength,
(∼500 nm). The production of flat top drive laser beams, high peak
current bunches, and emittance compensation scheme will be investigated
together with the generation of higher harmonic radiation in the VUV
region. SPARX is the direct evolution of such a high gain SASE FEL
toward the 13.5 and 1.5 nm operating wavelengths, at 2.5 GeV. To get
the required value for the bunch peak current, Ipeak ≈
2.5 kA, the “hybrid” scheme, RF-compression stage plus
magnetic chicane, is analyzed and compared with the more standard
double stage of magnetic compression. The two options are reviewed
considering the tolerance to the drive laser pulse phase jitter.
The solution structure and stability of N-terminally
truncated β2-microglobulin (ΔN6β2-m), the major
modification in ex vivo fibrils, have been investigated
by a variety of biophysical techniques. The results show
that ΔN6β2-m has a free energy of stabilization
that is reduced by 2.5 kcal/mol compared to the intact
protein. Hydrogen exchange of a mixture of the truncated
and full-length proteins at μM concentrations at pH
6.5 monitored by electrospray mass spectrometry reveals
that ΔN6β2-m is significantly less protected than
its wild-type counterpart. Analysis of ΔN6β2-m
by NMR shows that this loss of protection occurs in β
strands I, III, and part of II. At mM concentration gel
filtration analysis shows that ΔN6β2-m forms a
series of oligomers, including trimers and tetramers, and
NMR analysis indicates that strand V is involved in intermolecular
interactions that stabilize this association. The truncated
species of β2-microglobulin was found to have a higher
tendency to self-associate than the intact molecule, and
unlike wild-type protein, is able to form amyloid fibrils
at physiological pH. Limited proteolysis experiments and
analysis by mass spectrometry support the conformational
modifications identified by NMR and suggest that ΔN6β2-m
could be a key intermediate of a proteolytic pathway of
β2-microglobulin. Overall, the data suggest that removal
of the six residues from the N-terminus of β2-microglobulin
has a major effect on the stability of the overall fold.
Part of the tertiary structure is preserved substantially
by the disulfide bridge between Cys25 and Cys80, but the
pairing between β-strands far removed from this constrain
is greatly perturbed.
The Authors have investigated by means of the immuno-electrophoretic method the protein composition of the funicular blood of 19 twin-pairs from pregnancies of 5 to 9 months. Monochorionic twins showed a concordant picture, while in 7 of the 14 bichorionic twin-pairs slight differences could be observed, due to the presence in one of the twins of one or two more lines. The Authors put these results in correlation with the hypothesis of a genie control of the production of proteins.
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