3,808 research outputs found
Bipolar Quantum Molecular Resonance versus Blunt Dissection tonsillectomy
Bipolar Quantum Molecular Resonance versus Blunt Dissection tonsillectomy. Objectives: This study compared a quantum molecular resonance tonsillectomy (QMRT) to a standard blunt dissection tonsillectomy (BDT) for effectiveness and safety. Methodology: From January 2011 to September 2012, we recruited 80 children (ages 3 to 16 y) with paediatric obstructive sleep apnoea syndrome and/or recurrent tonsillitis. Patients were randomly assigned to receive QMRT (N = 40) or BDT (N = 40). The operating time and blood loss during surgery were evaluated. During the first postoperative week, the patients' parents completed a questionnaire to evaluate bleeding, ear and neck pain, nausea, vomiting, interrupted sleep, oral liquid intake or discomfort in fluid assumption, and analgesic consumption. Results: The average tonsillectomy duration was significantly shorter in the QMRT group (22.07 min \ub1 9.05) than in the BDT group (35.12 min \ub1 13.32; p < 0.000005). The average blood loss during tonsillectomy was significantly lower for the QMRT group (5.62 ml \ub1 7.44) than for the BDT group (43 ml \ub1 33.20; p < 000000001). However, the BDT group reported significantly lower pain scores than the QMRT group on days 2 (p < 0.05), 5 (p < 0.05), and 6 (p < 0.05); on other days, the groups were not significantly different. The BDT group reported two early and one late bleeding episodes; the QMRT group recorded only two late bleeding episodes. Conclusions: QMRT significantly reduced the operating time and intra-operative blood loss. No significant differences were found between the two techniques in postoperative pain or bleeding
The puzzling case of the accreting millisecond X-ray pulsar IGR J00291+5934: flaring optical emission during quiescence
We present an optical (gri) study during quiescence of the accreting
millisecond X-ray pulsar IGR J00291+5934 performed with the 10.4m Gran
Telescopio Canarias (GTC) in August 2014. Despite the source being in
quiescence at the time of our observations, it showed a strong optical flaring
activity, more pronounced at higher frequencies (i.e. the g band). Once the
flares were subtracted, we tentatively recovered a sinusoidal modulation at the
system orbital period in all bands, even if a significant phase shift with
respect to an irradiated star, typical of accreting millisecond X-ray pulsars
is detected. We conclude that the observed flaring could be a manifestation of
the presence of an accretion disc in the system. The observed light curve
variability could be explained by the presence of a superhump, which might be
another proof of the formation of an accretion disc. In particular, the disc at
the time of our observations was probably preparing to the new outburst of the
source, that happened just a few months later, in 2015.Comment: 6 pages, 2 figures, 1 table. Accepted for publication in A&
SAX J1808.4-3658, an accreting millisecond pulsar shining in gamma rays?
We report the detection of a possible gamma-ray counterpart of the accreting
millisecond pulsar SAX J1808.4-3658. The analysis of ~6 years of data from the
Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi-LAT)
within a region of 15deg radius around the position of the pulsar reveals a
point gamma-ray source detected at a significance of ~6 sigma (Test Statistic
TS = 32), with position compatible with that of SAX J1808.4-3658 within 95%
Confidence Level. The energy flux in the energy range between 0.6 GeV and 10
GeV amounts to (2.1 +- 0.5) x 10-12 erg cm-2 s-1 and the spectrum is
well-represented by a power-law function with photon index 2.1 +- 0.1. We
searched for significant variation of the flux at the spin frequency of the
pulsar and for orbital modulation, taking into account the trials due to the
uncertainties in the position, the orbital motion of the pulsar and the
intrinsic evolution of the pulsar spin. No significant deviation from a
constant flux at any time scale was found, preventing a firm identification via
time variability. Nonetheless, the association of the LAT source as the
gamma-ray counterpart of SAX J1808.4-3658 would match the emission expected
from the millisecond pulsar, if it switches on as a rotation-powered source
during X-ray quiescence.Comment: 8 pages, 4 figures, accepted by MNRA
An XMM-Newton and INTEGRAL view on the hard state of EXO 1745-248 during its 2015 outburst
CONTEXT - Transient low-mass X-ray binaries (LMXBs) often show outbursts
lasting typically a few-weeks and characterized by a high X-ray luminosity
( erg/sec), while for most of the time they are
found in X-ray quiescence ( erg/sec). EXO 1745-248
is one of them. AIMS - The broad-band coverage, and the sensitivity of
instrument on board of {\xmm} and {\igr}, offers the opportunity to
characterize the hard X-ray spectrum during {\exo} outburst. METHODS - In this
paper we report on quasi-simultaneous {\xmm} and {\igr} observations of the
X-ray transient {\exo} located in the globular cluster Terzan 5, performed ten
days after the beginning of the outburst (on 2015 March 16th) shown by the
source between March and June 2015. The source was caught in a hard state,
emitting a 0.8-100 keV luminosity of ~{\lumcgs}. RESULTS - The
spectral continuum was dominated by thermal Comptonization of seed photons with
temperature keV, by a cloud with moderate optical depth
and electron temperature keV. A weaker soft
thermal component at temperature --0.7 keV and compatible
with a fraction of the neutron star radius was also detected. A rich emission
line spectrum was observed by the EPIC-pn on-board {\xmm}; features at energies
compatible with K- transitions of ionized sulfur, argon, calcium and
iron were detected, with a broadness compatible with either thermal Compton
broadening or Doppler broadening in the inner parts of an accretion disk
truncated at gravitational radii from the neutron star. Strikingly, at
least one narrow emission line ascribed to neutral or mildly ionized iron is
needed to model the prominent emission complex detected between 5.5 and 7.5
keV. (Abridged)Comment: 14 pages, 6 figure, 2 tables. Accepted for publication on A&A
(21/03/2017
Discovery of 105 Hz coherent pulsations in the ultracompact binary IGR J16597-3704
We report the discovery of X-ray pulsations at 105.2 Hz (9.5 ms) from the
transient X-ray binary IGR J16597-3704 using NuSTAR and Swift. The source was
discovered by INTEGRAL in the globular cluster NGC 6256 at a distance of 9.1
kpc. The X-ray pulsations show a clear Doppler modulation implying an orbital
period of ~46 minutes and a projected semi-major axis of ~5 lt-ms, which makes
IGR J16597-3704 an ultra-compact X-ray binary system. We estimated a minimum
companion mass of 0.0065 solar masses, assuming a neutron star mass of 1.4
solar masses, and an inclination angle of <75 degrees (suggested by the absence
of eclipses or dips in its light-curve). The broad-band energy spectrum of the
source is well described by a disk blackbody component (kT ~1.4 keV) plus a
comptonised power-law with photon index ~2.3 and an electron temperature of ~30
keV. Radio pulsations from the source were searched for with the Parkes
observatory and not detected.Comment: 4 pages, 4 images, Accepted for publication in A&
A phase II study of induction chemotherapy followed by concurrent chemoradiotherapy in elderly patients with locally advanced non-small-cell lung cancer.
The optimal management of unresectable locally advanced non-small-cell lung cancer in older patients has not been defined to date. The present phase II study was planned to evaluate the activity and safety of platinum-based induction chemotherapy followed by concurrent chemoradiotherapy in elderly patients with locally advanced non-small-cell lung cancer. Patients received two cycles of paclitaxel (175 mg/m) and carboplatin (area under the curve: 5) day 1, every 3 weeks. Chemoradiotherapy (thoracic radiation therapy) was initiated on day 42 and consisted of 1.8 Gy daily, five times per week over 5 weeks (45.0 Gy target dose) followed by 10 2.0 Gy daily fractions. Concomitant chemotherapy was weekly paclitaxel 50 mg/mq followed by weekly carboplatin at an area under the curve of 2. The eligibility for patients: age 70 or older and histologically documented untreated non-small-cell lung cancer, locally advanced, unresectable, stage III A N2 bulky or III B. Thirty consecutive patients were enrolled onto the study. The median age was 73 (range 70-76). According to the intention-to-treat analysis, 1 month after the end of combined chemoradiotherapy, we observed complete and partial responses in one and 19 of the 30 patients, respectively, for an overall response rate of 66% (95% confidence interval, 45-76%). Median progression-free survival was 8.7 months (95% confidence interval, 3.4-37.8) and median survival was 15 months (95% confidence interval, 4.2-52.1). During the treatment, 12 patients (40.0%) experienced grade 3-4 neutropenia, two patients neutropenic fever, and three patients grade 3 anaemia and grade 3 thrombocytopenia, respectively. Grade 3 oesophagitis, during concomitant radiotherapy, was observed in six patients (20.0%). No treatment-related mortality was reported. The investigated sequential approach including induction chemotherapy followed by concurrent chemoradiotherapy appears safe and seems a reasonable chance for the treatment of locally advanced non-small-cell lung cancer in the elderly population
Sweat analysis with a wearable sensing platform based on laser-induced graphene
The scientific community has shown increasing interest in laser scribing for the direct fabrication of conductive graphene-based tracks on different substrates. This can enable novel routes for the noninvasive analysis of biofluids (such as sweat or other noninvasive matrices), whose results can provide the rapid evaluation of a person's health status. Here, we present a wearable sensing platform based on laser induced graphene (LIG) porous electrodes scribed on a flexible polyimide sheet, which samples sweat through a paper sampler. The device is fully laser manufactured and features a two layer design with LIG-based vertical interconnect accesses. A detailed characterization of the LIG electrodes including pore size, surface groups, surface area in comparison to electroactive surface area, and the reduction behavior of different LIG types was performed. The bare LIG electrodes can detect the electrochemical oxidation of both uric acid and tyrosine. Further modification of the surface of the LIG working electrode with an indoaniline derivative [4-((4-aminophenyl)imino)-2,6-dimethoxycyclohexa-2,5-dien-1-one] enables the voltammetric measurement of pH with an almost ideal sensitivity and without interference from other analytes. Finally, electrochemical impedance spectroscopy was used to measure the concentrations of ions through the analysis of the sweat impedance. The device was successfully tested in a real case scenario, worn on the skin during a sports session. In vitro tests proved the non-cytotoxic effect of the device on the A549 cell line
Chandra Observation of the Dipping Source XB 1254-690
We present the results of a 53 ks long Chandra observation of the dipping
source XB 1254--690. During the observation neither bursts or dips were
observed. From the zero-order image we estimated the precise X-ray coordinates
of the source with a 90% uncertainty of 0.6\arcsec. Since the lightcurve did
not show any significant variability, we extracted the spectrum corresponding
to the whole observation. We confirmed the presence of the \ion{Fe}{xxvi}
K absorption lines with a larger accuracy with respect to the previous
XMM EPIC pn observation. Assuming that the line width were due to a bulk motion
or a turbulence associated to the coronal activity, we estimate that the lines
were produced in a photoionized absorber between the coronal radius and the
outer edge of the accretion disk.Comment: 8 pages, 10 figs, accepted by A&A on 6 December 200
A self-consistent approach to the hard and soft states of 4U 1705-44
Context. High-resolution spectroscopy has recently revealed in many low-mass X-ray binaries hosting a neutron star that the shape of the broad iron line observed in the 6.4-6.97 keV range is consistently well-fitted by a relativistically smeared line profile.
Aims: The presence of other broad features, besides the iron line, together with a high S/N of the spectra offer the possibility of testing a self-consistent approach to the overall broadband reflection spectrum and evaluating the impact of the reflection component in the formation of the broadband X-ray spectra.
Methods: We analyzed two XMM-Newton observations of the bright atoll source 4U 1705-44, which can be considered a prototype of the class of the persistent NS LMXBs showing both hard and soft states. The first observation was performed when the source was in a hard low flux state, the second during a soft, high-flux state. Both the spectra show broad iron emission lines. We fit the spectra using a two-component model, together with a reflection model specifically suited to the case of a neutron star, where the incident spectrum has a blackbody shape.
Results: In the soft state, the reflection model, convolved with a relativistic smearing component, consistently describes the broad features present in the spectrum, and we find a clear relation between the temperature of the incident flux and the temperature of the harder X-ray component that we interpret as the boundary layer emission. In this state we find converging evidence that the boundary layer outer radius is ~2 times the neutron star radius. In the low flux state, we observe a change in the continuum shape of the spectrum with respect to the soft state. Still, the broad local emission features can be associated with a disk reflecting matter, but in a lower ionization state, and possibly produced in an accretion disk truncated at greater distance.
Conclusions: Our analysis provides strong evidence that the reflection component in soft states of LMXBs comes from to hard X-ray thermal irradiation, which we identify with the boundary layer emission, also present in the continuum model. In the hard state, the broad iron line if also produced by reflection, and the continuum disk emission can be self-consistently accounted if the disk is truncated at a greater distance than the soft state
Upscaling cervical cancer screening and treatment for women living with HIV at a rural referral hospital in Tanzania: protocol of a before-and-after study exploring HPV testing and novel diagnostics
BACKGROUND: Cervical cancer (CC) is nearly always caused by persistent human papillomavirus (HPV) infection. It is the most common cancer among women living with HIV (WLWH) and is the leading cause of cancer-related death in women in East Africa, with 10,241 new cases reported in Tanzania in 2020. In 2019, the World Health Organization (WHO) presented a global strategy for the elimination of CC as a public health problem, proposing targets to meet by 2030 for HPV vaccine coverage (90% of all 15-year-old girls), CC screening (70% of all women once at 35 and again at 45 years of age) and treatment delivery, to be scaled at national and subnational levels with a context-sensitive approach. This study aims to evaluate the upscaling of screening and treatment services at a rural referral hospital in Tanzania in order to address the second and third WHO targets. METHODS: This is an implementation study with a before-and-after design performed at St. Francis Referral Hospital (SFRH) in Ifakara (south-central Tanzania). CC screening and treatment services are integrated within the local HIV Care and Treatment Center (CTC). The standard of care, consisting of visualization of the cervix with acetic acid (VIA) and cryotherapy has been up-scaled with self-sampled HPV testing and also involved the introduction of mobile colposcopy, thermal ablation and loop electrosurgical excision procedure (LEEP). Participants are WLWH aged 18 to 65 years. Outcome measures included the percentage of women screened, HPV prevalence and genotype, and adherence to screening, treatment and follow-up plan. Additionally, we will explore the performance of novel diagnostic tests (QG-MPH(R), Prevo-Check(R) and PT Monitor(R)), which share the features of being manageable and inexpensive, and thus a potential tool for effective triage in HPV high-prevalence cohorts. DISCUSSION: The study will provide relevant information about HPV prevalence and persistence, as well as reproductive and lifestyle indicators in a CC high-risk cohort of WLWH and about upscaling screening and treatment services at the level of a rural referral hospital in Tanzania. Furthermore, it will provide exploratory data on novel assays. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT05256862, date of registration 25/02/2022. Retrospectively registered
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