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To assess the relapse-free survival (RFS) and the factors influencing local recurrence in patients with desmoid fibromatosis (DF) treated at our centre and to determine the role of post-operative radiotherapy (RT) in improving local control.
A retrospective analysis of 51 patients treated for DF from January 2004 to December 2013 was undertaken. The RFS was calculated using the Kaplan–Meier curve. Univariate analysis was done to assess correlation with tumour size, site, the extent of surgery, margin status and adjuvant RT with RFS.
The median age was 28 years with a male:female ratio of 1:3. The most common location of the tumour was anterior abdominal wall (47%). The median tumour size was 10 cm. Wide local excision was done in most patients. Complete resection with negative margin was achieved in eight patients. Post-operative RT was indicated for 43 patients of whom 19 received RT. At a median follow-up of 37 months, RFS in the complete resection with margin negative group was 100%. RFS for the patients with positive or close margins who received RT was 79% and for those who did not receive RT, it was 87%.
Complete excision with negative margins gives the best local control in DF. The benefit of post-operative RT could not be ascertained.
This article presents a potential analytic redundancy approach to detect faults in the air data sensor of an aircraft. In modern aircraft, fault detection of air data sensors is performed using a complex voting mechanism, which requires the availability of redundant air data sensor in all situations. However, to continuously monitor operation and performance of these sensors, the analytic redundancy-based air data estimation and fault detection is highly preferred than estimation with air data probe measurements. The proposed algorithm uses the kinematics of aircraft to estimate air data and detect air data sensor fault. In this paper, a simple mathematical model is developed, which does not consider the forces and moments acting on aircraft and uses measurements only from the Inertial Measurement Unit (IMU) and Navigation System Data (NSD). In order to implement this approach, the Iterated Optimal Extended Kalman Filter (IOEKF) is developed to estimate air data, which provides an accurate and stable estimation. With the estimated states, the physical air data sensor measurements are compared and the residual is calculated to track each sensor performance and to detect the occurrence of a fault. The key advantage of this approach is that it does not require complex dynamic equations and is free from system uncertainties. The proposed algorithm is simulated in MATLAB software using flight simulator flight data and validated using the real-time flight data of Cessna Citation II transport aircraft.
Placental structure and function determine birth outcomes. Placental mass does not always correlate with fetal birth weight (BW) in uncomplicated pregnancies which raises the possibility of other variables such as placental shape and cord insertion being the determinants of placental efficiency. In total, 160 women with singleton pregnancy, recruited into a pregnancy cohort were studied. Placental weight (PW) was measured and other data were obtained from clinical records. Birth outcomes were classified as small for gestational age (SGA) and appropriate for gestational age (AGA) based on fetal gender, gestational age (GA) and BW. High-resolution images of the chorionic plate were recorded. The shape of the placenta and the insertion of the cord were measured using eccentricity index (EI) and cord centrality index (CCI). Only placentae with eccentrically inserted cords (n=136) were included. The mean BW and PW were 2942 (±435) g and 414 (±82) g with average GA of 38.6 weeks. The mean CCI and EI was 0.483 (±0.17) and 0.482 (±0.16). Neither of these correlated with placental efficiency. However, EI showed negative correlation with placental surface area and breadth. Upon sub-grouping the cohort into SGA (n=32) and AGA (n=104), the SGA babies with the highest EI (third tertile) had significantly lower BW than those with the least eccentric placentae (first tertile). Although eccentric-shaped placentae were present in both SGA and AGA groups, the effect on BW was observed only in the SGA group.
The focused ion beam (FIB) has the necessary precision, spatial resolution and control over ion delivery for potential nano-scale doping of nanostructures such as semiconductor quantum dots (QDs). The ion current density in a FIB is 0.1-10 A/cm2, which is at least three orders of magnitude higher than that in a commercial broad beam ion implanter. Therefore an understanding of FIB implantation damage and recovery is of substantial interest. In this work we employ Raman probes of wavelengths 514 nm and 405 nm for quantifying ion implantation damage—both before and after annealing—in 30 kV Si2+, Ge2+ and Ga+ implants (fluences: 1x1012-5x1015 ions/cm2) into Si(100), for the purpose of understanding the effect of ion species on damage recovery.
We present an analysis of the optical nuclear spectra from the active galactic nuclei (AGN) in a sample of giant low surface brightness (GLSB) galaxies. GLSB galaxies are extreme late type spirals that are large, isolated and poorly evolved compared to regular spiral galaxies. Earlier studies have indicated that their nuclei have relatively low mass black holes. Using data from the Sloan Digital Sky Survey (SDSS), we selected a sample of 30 GLSB galaxies that showed broad Hα emission lines in their AGN spectra. In some galaxies such as UGC 6284, the broad component of Hα is more related to outflows rather than the black hole. One galaxy (UGC 6614) showed two broad components in Hα, one associated with the black hole and the other associated with an outflow event. We derived the nuclear black hole (BH) masses of 29 galaxies from their broad Hα parameters. We find that the nuclear BH masses lie in the range 105 – 107 M⊙. The bulge stellar velocity dispersion σe was determined from the underlying stellar spectra. We compared our results with the existing BH mass - velocity dispersion (MBH–σe) correlations and found that the majority of our sample lie in the low BH mass regime and below the MBH–σe correlation. The effects of galaxy orientation in the measurement of σe and the increase of σe due to the effects of bar are probable reasons for the observed offset for some galaxies, but in many galaxies the offset is real. A possible explanation for the MBH–σe offset could be lack of mergers and accretion events in the history of these galaxies which leads to a lack of BH-bulge co-evolution.
A single specimen of latticed sandperch, Parapercis clathrata measuring 163 mm total lenth was caught in a trawler off Tuticorin, south-east coast of India in February 2010. Morphometric and meristic characters of the recorded specimen are described. This record constitutes the first occurrence of the species in Indian waters and a substantial westward extension of its known geographical distribution.
Single wafer amorphous silicon deposition was characterized through process modeling and film characterization for application in semiconductor production. DOE methodology was used to determine the main deposition parameters, and the responses were limited to device production requirement properties of surface roughness, deposition rate and degree of crystallinity of the as-deposited film. The data trends and models show that deposition temperature and silane flow are the main factors. Increasing either or both factor increases the deposition rate and the surface roughness. The surface morphology, evaluated by AFM, SEM and TEM, was found to be rougher at extreme growth conditions than the poly crystalline film formed after anneal. The as-deposited surface morphology was not a result of pre-anneal crystal formations as determined by TEM cross sections of samples before and after anneal. Lack of crystalinity is important for impurity diffusion considerations. Device application of the single wafer a-Si process will be a compromise between growth rate (and associated throughput) and surface roughness that can be tolerated.
Tantalum pentoxide (Ta2O5) films were formed by oxidizing thin tantalum (Ta) films on bare and NO-nitrided silicon substrates. The 43-400 Å thick Ta films were deposited using physical vapor deposition (PVD) and oxidized using O2 for 2-60 min at 550-800 C in a furnace or single wafer tool. Uniform and stoichiometric Ta2O5 films were successfully produced as determined from XRD, AES depth profiling, XTEM, and ellipsometric analysis. The nitridation pretreatment was found to minimize the interfacial Ta-Si reactions which occur during the oxidation. Well-behaved CV and IV curves were obtained from mercury probe measurements. No CV hysteresis was observed. An equivalent oxide thickness of 38 Å and a leakage current of 7×10−9 A/cm2 at +1V were obtained for a 120 Å thick Ta2O5 film on a 15 Å interfacial SiO2 layer.
The slow flow of granular materials is often marked by the existence of narrow shear layers, adjacent to large regions that suffer little or no deformation. This behaviour, in the regime where shear stress is generated primarily by the frictional interactions between grains, has so far eluded theoretical description. In this paper, we present a rigid-plastic frictional Cosserat model that captures thin shear layers by incorporating a microscopic length scale. We treat the granular medium as a Cosserat continuum, which allows the existence of localised couple stresses and, therefore, the possibility of an asymmetric stress tensor. In addition, the local rotation is an independent field variable and is not necessarily equal to the vorticity. The angular momentum balance, which is implicitly satisfied for a classical continuum, must now be solved in conjunction with the linear momentum balances. We extend the critical state model, used in soil plasticity, for a Cosserat continuum and obtain predictions for flow in plane and cylindrical Couette devices. The velocity profile predicted by our model is in qualitative agreement with available experimental data. In addition, our model can predict scaling laws for the shear layer thickness as a function of the Couette gap, which must be verified in future experiments. Most significantly, our model can determine the velocity field in viscometric flows, which classical plasticity-based model cannot.
1. The growth of a number of inbred lines from the Pacific cage population have been compared under different conditions of temperature and nutrition. Body size and duration of the larval period were taken as measures of performance. Sub-optimal diets were provided by growing larvae on chemically defined synthetic media.
2. Gene-environment interaction is widespread and often very great. The phenotypic effects of inbreeding on body size, even on a live yeast medium, may be greatly influenced by temperature. In one set of comparisons, inbred lines averaged 20% smaller at 25° C. but only 3% smaller at 18° C.
3. Sub-optimal diets of different chemical composition, which lead to about the same average decline in body size, may differ greatly in the level of heterogeneity of response among the same set of inbred lines. Thus much greater heterogeneity was found on diets deficient in RNA than on diets with low protein levels. Such information is a useful guide to further study of gene-environment interaction in the outbred population.
4. Diets which lead to a decline in body size of flies of the foundation population do not necessarily cause greater proportional decline on the part of inbred lines. Individual lines have been encountered in which body size is quite unaffected by changes in diet which reduce the size of the outbred flies by 25% or more.
5. A series of crosses between lines from the same foundation population showed a striking level of homeostasis. The average body size and development time of the F1's was close to that of the population of flies on the favourable and two alternative sub-optimal diets. Also, compared with the parent lines, there was little evidence of gene-environment interaction among the crosses.
We have investigated the flow of dry granular materials through vertical channels in the regime of dense slow flow using video imaging of the particles adjacent to a transparent wall. Using an image processing technique based on particle tracking velocimetry, the video movies were analysed to obtain the velocities of individual particles. Experiments were conducted in two- and three-dimensional channels. In the latter, glass beads and mustard seeds were used as model granular materials, and their translational velocities were measured. In the former, aluminium disks with a dark diametral stripe were used and their translational velocities and spin were measured. Experiments in the three-dimensional channels were conducted for a range of the channel width W, and for smooth and rough sidewalls. As in earlier studies, we find that shearing takes place predominantly in thin layers adjacent to the walls, while the rest of the material appears to move as a plug. However, there are large velocity fluctuations even in the plug, where the macroscopic deformation rate is negligibly small. The thickness of the shear layer, scaled by the particle diameter dp, increases weakly with W/dp. The experimental data for the velocity field are in good agreement with the Cosserat plasticity model proposed recently. We also measured the mean spin of the particles in the two-dimensional channel, and its deviation from half the vorticity. There is a clear, measurable deviation, which too is in qualitative agreement with the Cosserat plasticity model. The statistics of particle velocity and spin fluctuations in the two-dimensional channel were analysed by determining their probability distribution function, and their spatial and temporal correlation. They were all found to be broadly similar to previous observations for three-dimensional channels, but some differences are evident. The spatial correlation of the velocity fluctuations are much stronger in the two-dimensional channel, implying a pronounced solid-like motion superimposed over an uncorrelated fluid-like motion. The strong spatial correlation over large distances has led us to propose a mechanism for the production of velocity fluctuations in the absence of a macroscopic deformation rate.
We report a case and review the recent literature describing 36 patients with both Lhermitte-Duclos disease (LDD) and Cowden disease (CD). Lhermitte-Duclos disease, or dysplastic gangliocytoma, is a benign hamartomatous condition involving the cerebellum. The presenting symptoms are usually headaches, gait ataxia, and symptoms of lower cranial nerve involvement. Cowden disease is a rare autosomal dominant disease that usually presents with multiple mucocutaneous lesions. Patients with CD are prone to multiple systemic malignancies, the most common of which is breast cancer. Recent studies have demonstrated an association between LDD and CD.
A 44-year-old woman with a previous history of breast cancer, multiple benign skin lesions, Hashimoto's thyroiditis, and chronic headaches presented with exacerbation of her headaches during the previous year. Magnetic resonance imaging of the brain revealed a right cerebellar nonenhancing mass and an acquired tonsillar herniation.
The patient underwent resection of the right cerebellar mass, posterior fossa decompression, C1 and C2 laminectomies, and a duraplasty. Pathologic examination confirmed LDD. The patient recovered well after surgery, with immediate improvement of her headaches.
The association between LDD and CD has been under-recognized and under-reported. Recognition of this association has direct clinical relevance, because diligent monitoring of individuals with LDD and CD may lead to the early detection of systemic malignancies.
Although the benefits of radiotherapy for pituitary adenomas are well-documented, post-irradiation sarcomas of the sella are rarely seen, with only 20 cases (mainly of fibrosarcoma) reported in the medical literature.
We describe a case of post-irradiation sarcoma five years after surgery followed by external-beam irradiation for an extensive and locally invasive growth hormone-secreting tumor. The patient was subsequently given pegvisomant, an antagonist of growth hormone receptor, to control symptoms of growth hormone excess.
The patient underwent transsphenoidal resection of the recurrent tumor, followed by adjuvant chemotherapy. This led to significant relief in the patient's symptoms including radiological evidence of tumor shrinkage, but the tumor regrew when, owing to dose-limiting toxicity, chemotherapy was stopped.
Post-irradiation sarcomas of the pituitary are well-recognized but rare. They should be suspected in patients following sellar irradiation who show abrupt onset of new symptoms and appropriate radiological findings, and such tumors may respond to cytotoxic chemotherapy.
Background and objective Variability in blink duration was examined to see whether it was sensitive to sevoflurane sedation at 0.05 and 0.1 minimum alveolar concentration (MAC).
Methods Blinks were measured with an infrared transducer in eight subjects. Sedation was scored using a visual analogue scale (VAS).
Results At baseline, 0.05 and 0.1 MAC sevoflurane, respectively, the overall median value of blink duration and its interquartile range were 95 (80–110) ms, 198 (163–245) ms and 210 (130–980) ms. The median percentage of blinks exceeding 500 ms was 0% (0–0.7%), 33.3% (25.5–34.7%) and 25% (15.7–63.3%) respectively. Values during 0.05 and 0.1 MAC sevoflurane were significantly different from baseline (P < 0.035) but not from each other. Baseline visual analogue scales showed large intersubject variability. Compared with baseline, VAS scores were higher at 0.05 MAC (P < 0.035) but not at 0.1 MAC. After discontinuing sevoflurane, median blink duration returned to baseline with a recovery half-life of 2.6 min (R2 = 0.95).
Conclusion Blink duration is a sensitive measure of sevoflurane sedation even at 0.05 MAC.
We report a case of non-ketotic hyperosmolar coma, which presented with blood sugar levels far exceeding any previously recorded in the literature. The patient developed acute renal failure, probably because of rhabdomyolysis, which was successfully managed with continuous veno-venous haemofiltration. He developed blurring of vision resulting from biochemical changes, which was managed conservatively. We discuss the mechanisms of causation of the renal failure and visual blurring.
Maximal voluntary contraction (MVC) using a handgrip dynamometer was assessed in seventy-two young adult males. The subjects were divided into two groups on the basis of a BMI of 18·5 kg/m2. The subjects with a BMI < 18·5 kg/m2 (n 38) were further divided into an underweight (UW;n 20) group and a chronically energy-deficient (CED; n 18) group. The CED subjects had significantly lower MVC (30·1, SD 5·9 kg) than either the well-nourished controls (BMI > 18·5 kg/m2: 39·8, SD 5·8 kg) or the underweight group (37·6, SD 4·9 kg). The differences between the CED and UW groups persisted even after the MVC were corrected for forearm muscle area and stature. The results suggest that MVC may be a useful functional indicator of nutritional status particularly in differentiating subjects with chronic undernutrition from individuals who are underweight and not undernourished but have similar BMI.