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We present simultaneous multi-frequency observations of PSR J1822–2256 for the first time, utilizing the unique capabilities of upgraded Giant Meterwave Radio Telescope (uGMRT). No emission is detected in about 10 % of pulses. At least two drift modes and a possibly third rare mode, occur for 66, 21 and 2 % pulses respectively (P3 ~ 17, 7.5 and 5 P0 respectively). The three drift modes and the nulls occur concurrently from 250 to 1500 MHz. Modal average profiles are distinct with their widths increasing with drift rate. These sub-pulse drift related profile mode-changes can provide independent probes of beam geometry and polar gap physics.
Although community-onset bloodstream infection (BSI) is recognized as a major cause of morbidity and mortality, its epidemiology has not been well defined in non-selected populations. We conducted population-based surveillance in the Interior Health West region of British Columbia, Canada in order to determine the burden associated with community-onset BSI. A total of 1088 episodes were identified for an overall annual incidence of 117·8/100 000 of which 639 (58·7%) were healthcare-associated (HA) and 449 (41·3%) were community-associated (CA) BSIs for incidences of 69·2 and 48·6/100 000, respectively. The incidence of community-onset BSI varied by age and gender and elderly males were at the highest risk. Overall 964 (88·6%) episodes resulted in hospital admission for a median length of stay of 8 days; the total days of acute hospitalization associated with community-onset BSI was 13 530 days or 1465 days/100 000 population per year. The in-hospital mortality rate was 10·6% (102/964) and this was higher for HA-BSI (72/569, 12·7%) compared to CA-BSI (30/395, 7·6%, P = 0·014) episodes. Community-onset BSI, especially HA-BSI, is associated with a major burden of illness.
We use radar images with decameter resolution to measure the sizes, shapes, spin states, mutual orbits, masses, and densities of components of asteroid binaries and triples. We simulate the spin-orbit dynamics of these systems and map the possible spin configurations of the satellites on surface of section plots. The presence of chaotic regions in the phase space has important consequences for the evolution of binary asteroids. It may substantially increase spin synchronization timescales, delay BYORP-type evolution, and extend the lifetime of binaries.
Marble, a non-porous stone composed of calcite, is subject to acid rain dissolution due to its relatively high dissolution rate. With the goal of preventing such damage, we have investigated the deposition of films of relatively insoluble hydroxyapatite (HAP) on marble. This paper investigates the factors that affect the nucleation and growth kinetics of HAP on marble. A mild, wet chemical synthesis route, in which diammonium hydrogen phosphate (DAP) salt was reacted with marble, alone and with cationic and anionic precursors under different reaction conditions, was used to produce inorganic HAP films on the mineral surface. Film nucleation, growth and metastable phase evolution were studied, using techniques such as scanning electron microscopy (SEM) and grazing incidence X-ray diffraction (GID). The onset of nucleation, and the growth rate of the film, increased with cationic (calcium) and anionic (carbonate) precursor additions. The calcium and phosphate precursors also influenced metastable phase formation, introducing a new phase.
This paper discusses the effectiveness of hydroxyapatite (HAP) as an inorganic consolidant for physically weathered Indiana Limestone, and as a coupling agent between limestone and a silicate consolidant. A double application is investigated, in which samples are coated with HAP followed by a commercially available silicate-based consolidant (Conservare® OH-100). To artificially weather limestone, a thermal degradation technique was utilized. Diammonium hydrogen phosphate (DAP) salt was reacted with limestone, alone and with cationic precursors, to produce HAP films. The dynamic elastic modulus, water sorptivity and tensile strength of the treated stones were evaluated. HAP was found to be an effective consolidant for weathered Indiana Limestone, and its performance was enhanced by addition of millimolar quantities of calcium chloride. However, HAP was not useful as a coupling agent; a double treatment with DAP is more effective than sequential treatment with DAP and Conservare®.
We perform a sensitivity analysis for a thus far unstudied mathematical model for the
formation, growth and lysis of clots in vitro. The sensitivity analysis procedure uses an
ensemble standard deviation for species concentrations, and is equivalent to a variance
decomposition procedure also available in the literature. Our analysis shows that fibrin
production is most sensitive to the rate constant governing activation of prothrombin to
thrombin. Further, the time-averaged sum of all species’ concentrations is most sensitive
to the rate constants governing the inactivation of VIIIa (intrinsic as well as by APC).
We therefore conclude that the rate constants for VIIIa inactivation affect the model the
greatest: this conclusion must be experimentally verified to determine if such is indeed
the case for hemostasis.
This study aimed to evaluate the incidence of submandibular gland metastases in cases of oral cavity squamous cell carcinoma.
Sixty-nine patients treated between 1 January 2004 and 30 June 2009 were retrospectively reviewed. Patients were treated with wide local excision of the primary tumour, plus simultaneous neck dissection and reconstruction if required.
Of 69 submandibular glands from 46 men and 23 women (mean age, 58 years), 43 (62.3 per cent) had advanced, tumour stage three or four lesions. Histopathological reappraisal of all submandibular glands demonstrated an absence of metastatic spread. Only 2/69 (2.9 per cent) submandibular glands demonstrated ipsilateral contiguous tumour involvement.
This study demonstrated an absence of metastasis to the submandibular gland from oral cavity squamous cell carcinoma. Patients with early stage oral cavity squamous cell carcinoma and with a pre-operative node stage zero neck may be candidates for preservation of the submandibular gland during neck dissection.
This paper develops a theoretical framework for the description and classification of small-amplitude waves with frequencies much less than the ion gyrofrequency, propagating in an ion-beam plasma system. In this respect, the results extend to the strongly magnetized regime the results obtained previously by Zank and McKenzie and applied by Greaves et al. to study wave propagation in such a system for frequencies in excess of the ion gyrofrequency but less than the electron plasma frequency. For completeness, the full wave equation governing an ion-beam plasma system for any strength of applied magnetic field is derived. In specializing to the strong-magnetic-field limit, we find that the class of refractive-index topologies (which characterize the kinematic properties of wave propagation) is less rich than in the un-magnetized case. After investigating the topology of the refractive-index surface and the phase-, ray- and group-velocity surfaces, we construct a CMA diagram appropriate to the strongly magnetized ion-beam plasma system. The temporal stability and spatial amplification of the slow ion-acoustic mode for frequencies less than the stationary ion plasma frequency is investigated. We show that a strong magnetic field normal to the drift direction of the ion beam stabilizes long-wavelength modes that would be unstable in the unmagnetized case.
This study examined the auditory status of females with Rett syndrome (RS) using auditory brainstem response (ABR) testing and measures of acoustic admittance. Prevalence of hearing impairment in 81 female patients (age range 1 year 3 months to 39 years 8 months; mean age 8 years 7 months, SD 6 years 4 months) was evaluated with ABR measurements. If the ABR latencies at 20dB nHL exceeded those of the normative group, a slight hearing loss was diagnosed. For ABR thresholds in the range 30 to 40dB nHL, a mild hearing loss was determined; moderate hearing loss was diagnosed for ABR thresholds in the range 50 to 60dB nHL. Bilateral hearing loss was found in 16 (19.3%) patients and unilateral hearing loss in 13 (16%) patients. Bilateral hearing loss of moderate degree was found in one patient. No patient was found with severe hearing loss (ABR threshold of 70dB nHL and above) in either ear. Slight hearing loss was found in 10.5% of ears (17 of 162), mild hearing loss in 14.2% of ears(23 of 162), and moderate hearing loss in 3.1% of ears (5 of 162). In 72.2% of ears (117 of 162), findings indicated the presence of normal peripheral auditory sensitivity. Prevalence of sensorineural hearing loss was 17.3% (28 of 162). Evidence of conductive involvement (conductive and mixed hearing loss) was observed in 9.9% of ears (16 of 162). In this cross-sectional study, the prevalence of hearing loss was increased in older RS participants and in those with seizures requiring the use of anticonvulsants. Neither the type of hearing loss nor the presence of preserved speech seemed to be correlated with the type of mutation in methyl-CpG-binding protein 2 (MeCP2) gene that is associated with RS.
Patients with schizophrenia differ from controls in several measures of brain structure and function, but it is uncertain how these relate to clinical features of the illness. We dichotomised patient groups by treatment response to test the hypothesis that treatment-resistant patients exhibit more marked biological abnormalities than treatment-responsive parients.
Twenty treatment-responsive and 20 treatment-resistant patients with schizophrenia, matched for sex, age, and illness duration, were compared by magnetic resonance imaging, single photon emission tomography, and detailed neuropsychological assessment.
Brain-imaging variables were not statistically related to treatment response, although poorly responsive patients had lower volumes of most brain structures. Several highly significant differences emerged between patient groups on neuropsychological testing. Episodic memory functioning distinguished patient groups even after we controlled for global cognitive impairment.
Cerebral structure and blood flow have a limited effect on treatment response in schizophrenia, but long-term episodic memory impairment is associated with, and may predict, poor prognosis.
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