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Background: CSF shunt obstruction secondary to omental adhesion alone, without cyst or pseudocyst formation, is rarely reported in the literature. Here we present a case of distal catheter obstruction due to omental wrapping with an atypical presentation of shunt failure. CT imaging demonstrated omental stranding. The shut revision was entirely laparoscopic. The case is supplemented with intraoperative images. Methods: Chart review and literature search. Results: 33-year-old female with right-sided cystoperitoneal shunt for posterior fossa arachinoid cyst who presented to ED with a picture of a surgical abdomen suggestive of acute cholecystitis. Interestingly, this patient had a gallbladder removed a year ago. CT abdomen showed non-specific findings of omental fat stranding around the tip of the catheter. Although this patient had no headache or any neurological symptoms, CT brain was done and showed increase in the cyst size. Diagnostic laparoscopy showed Intraoperative findings suggestive of active omental role in the aetiology of this shunt malfunction. After adequate adhesiolysis, the catheter was noted to be working and dripping CSF and repositioned into the peritoneal cavity. Conclusions: Shunt malfunctions due to omentoperitoneal adhesion is rarely reported but may in fact be under-recognized. This requires high index of suspicion especially in case of equivocal imaging.
Background: Intracranial intratumoural abscesses are rare occurrences typically treated with antibiotics and possible surgical resection. This study describes a meningioma-associated abscess and a review of the literature. Methods: Medical records and investigations were reviewed. A literature search of PubMed was completed. Results: A 56-year-old male presented with septic shock and dysuria. Urine culture isolated E. Coli, and he was treated with Ertapenem prior to discharge. A CT scan was ordered during hospitalization for unrelenting headaches, revealing a meningioma. Conservative management with follow-up as an outpatient was decided. However, he returned within two weeks with a fever and progressive left-sided weakness. A right frontal craniotomy for tumour resection was performed, and culture of necrotic-appearing tissue within the tumour revealed E. Coli. He was treated with Meropenem for six weeks, and at follow-up, the patient was asymptomatic. Our scoping review illustrated that 18 meningioma-associated abscesses have been reported in the literature since the first report in 1994. Conclusions: This case highlights the hematogenous spread of a urinary infection, resulting in an intratumoural abscess. Review of the literature indicated that, similarly, 39% of cases had recent or concurrant urinary tract infections. Future studies should seek to determine conclusive guidelines for diagnosing intratumoural abscesses.
This paper describes an overview of our recent discovery – clear demonstration that LiF crystals can be efficiently used as a high-performance neutron imaging detector based on optically stimulated luminescence of color centers generated by neutron irradiation. It is shown that the neutron images we have obtained are almost free from granular noise, have a spatial resolution of ${\sim}5.4~{\rm\mu}\text{m}$ and a linear response with a dynamic range of at least $10^{3}$. The high contrast and good sensitivity of LiF crystals allow us to distinguish two holes with less than 2% transmittance difference. We propose to use such detectors in areas where high spatial resolution with high image gradation resolution is needed, including diagnostics of different plasma sources such as laser and z-pinch produced plasmas.
Background: Temporal Lobe Epilepsy is associated with bilateral gray (GM) and white matter (WM) loss. After surgical treatment progressive bilateral temporal and extra-temporal WM change occur, however, less is known regarding post-operative GM change. We set out to measure contralateral hippocampal volume (CHV) following TLS. Methods: 1.5T-3D-1mm-isotropic-MPRAGE scans in 26 TLE patients and 3 controls in two groups: longitudinal (n=10)(imaged POD1,2,3,6,60,120 and >360d) and single post-operative scan (n=16). Manual volumetry protocols. Results: We find significant CHV atrophy at delayed scan relative to baseline (mean atrophy 26.8%). In the longitudinal group there is significant and progressive atrophy from baseline to POD4-8 (72.6+/-6.5%), POD60-360 (69.7+/-12.3%) and >360 (58.5+/-10.6%). No significant atrophy in either the control group HV or contralateral CV over time. No significant difference in mean HV at the most delayed exam for surgery type (p=0.13) or side (p=0.24). Conclusions: We find a statistically significant CHV atrophy following surgery which is progressive over time. Our longitudinal within-subject design describes the time course and extent more fully than previous work. Caudate analysis indicates that early CHV atrophy is not due to global atrophy following brain surgery but rather may be due to deafferentation and deefferentation. Finally, we find no significant difference in atrophy when analyzed by surgical approach or surgical side.
We have investigated an influence of positive polarization charges generated at an interface between GaN barrier/p-AlGaN EB (Electron Blocking) layer in a blue-LED. Simulation results suggested that such polarization charges caused an electron overflow from QWs. The simulation results also indicated that sufficient acceptor doping at the interface could neutralize the positive polarization charges and suppress the electron overflow. We then demonstrated the electron overflow caused by the positive polarization charges and its suppression with sufficient Mg doping at the interface by monitoring emissions from an additional second QW inserted between the p-EB layer and the p-GaN layer. Finally we conclude that the contribution of the electron overflow is not significant for the efficiency droop in blue-LEDs.
We investigated MOVPE growth conditions for AlInN layers with high growth rates and obtained 0.5µm/h with smooth surfaces. We found that short gas mixing time, relatively high growth temperature, and very low In/Al supply ratio were key growth parameters in order to obtain the AlInN layers with high growth rate and smooth surface simultaneously. AlInN/GaN DBRs grown under such growth conditions showed smooth surfaces and a reflectivity of over 99%.
Soil type may drive vegetation structure. In turn, the richness, identity and diversity of arthropod herbivores may be related to plant diversity through specific host plant relationships in a location. We test the hypothesis that the soil type (calcicolous vs alluvial soils) will drive the assemblage structure of a dominant group of arthropod herbivores: the moths. We used sampling sites in rain-forest fragments in south-western China around the Xishuangbanna Tropical Botanical Gardens (21°41′N, 101°25′E) to test this hypothesis. We used Pennsylvania style light traps to take point samples of macromoths and pyraloids from four sampling sites in forest remnants on a limestone geological base and four from alluvial-based forest. A total of 3165 moths (1739 from limestone-based and 1255 from alluvium-based forests) was collected representing 1255 species. The limestone-based sites showed statistically similar levels of species richness and other alpha diversity indices to the four alluvium-based site. Nevertheless the sites were clearly significantly different in terms of species composition. Analysis of contrasting similarity (‘beta’ diversity) indices suggested that there was ‘leakage’ between the two classes of sites when ‘rare’ species were emphasized in the calculations. We used an indicator value procedure to select species that most characterized this separation. We expect that these differences reflect associated changes in plant assemblage structure acting through the herbivorous habits of larval moths. Accordingly, in any assessment of landscape level diversity the nature of the substrate and its associated vegetation is clearly of great importance. This observation also has consequences for the design of conservation programmes.
Often, silver nanoparticles (AgNps) are looked at in the realm of their plasmonic effects that are characterized by unique absorptional bands in the visible spectrum. Herein, the kinetics of a simple gravity mediated sedimentation process of AgNps, in aqueous suspensions. The surface energy mismatch between the AgNps and the receiver substrate allow for the formation of irregularly shaped AgNp microclusters with interconnected microchannels with dimensions and particle density controlled by the distance between the exposed substrate surface and the water/suspension interface. An investigation of the interplay between these properties and the films’ nanoparticle density is presented.
We review observational results of PAH emission in harsh interstellar environments, whichare mostly based on recent works by Spitzer and AKARI. The harsh environments includeshock regions in our Galaxy, the ionized superwinds and haloes of external galaxies, andthe hot plasmas of elliptical galaxies. Owing to the unprecedented high sensitivity forPAH emission with Spitzer and AKARI, it is found that an appreciable amount of PAHs arepresent in some cases with such hostile conditions. Some of them exhibit unusual PAHinterband strength ratios, reflecting either evolution of PAHs or physical conditions ofthe ISM. The distribution of the PAH emission, as compared to that of dust emission, isshown to discuss their ways of evolution and survival.
Napoleon Bonaparte's remarkable political and military career was ended by Wellington at Waterloo in 1815. He died at age 52 on St. Helena in 1821 due to gastric cancer. Napoleon had a childhood of poverty, a poor diet in his early career, and a strong family history of gastric cancer, all of which contributed to his demise. It is now apparent that Helicobacter pylori, acting in the context of host genetic susceptibility, is responsible for most cases of stomach cancer. Napoleon was most likely infected with H. pylori – an example of the bacterium being mightier than the sword. This interaction between bacterium and host offers a new paradigm for carcinogenesis in the gastrointestinal (GI) tract and provides clues to the prevention and screening of this lethal malignancy.
As information concerning the epidemiology and molecular genetics of gastric cancer improves, sophisticated strategies for early detection and prevention of this disease in high-risk areas of the world will be developed. Eventually, molecular techniques will help identify those people at highest risk for this disease, so that resource-intensive endoscopic screening programs can be directed to this population. It is possible that, with directed use, screening programs will be validated by gastric cancer mortality reduction.
In this chapter, new concepts and horizons concerning prevention, screening, diagnosis, and treatment of patients with gastric adenocarcinoma are presented.
This paper summarizes research activities in National Institute of Radiological Sciences (NIRS) for evaluation of the radiation effects on selected terrestrial and aquatic organisms as well as the ecosystems. Seven organisms, conifers, fungi, earthworms, springtails, algae, daphnia and Medaka are presently selected to study. For the estimation of possible radiation dose, transfers of radionuclides and related elements from medium to organisms are evaluated. Dose-effect relationships of acute gamma radiation on the survival, growth, and reproduction of selected organisms have been studied. Studies on the effect of chronic gamma radiation at low dose rate were also started. In order to understand the mechanism of radiation effects and to find possible indicators of the effects, information of genome- and metagenome-wide gene expression has been collected. Evaluation of ecological effects of radiation is more challenging task. Study methods by using three-species microcosm were established, and an index for the holistic evaluation of effects on various ecological parameters was proposed. The microcosm has been simulated as a computer simulation code. Developments of more complicated and practical model ecosystems have been started. The Denaturant Gradient Gel Electrophoresis (DGGE) has been applied on soil bacterial community in order to evaluate the radiation effects on soil ecosystems.
Inulin, a linear β fructan, is present in a variety of plants including chicory root and wheat. It exhibits prebiotic properties and has been shown to enhance mineral absorption and increase beneficial bacteria in the colon. The aim of the present study was to assess the effect of dietary inulin on the gene expression of selected intestinal Fe transporters and binding proteins. Anaemic piglets at age 5 weeks were allocated to a standard maize–soya diet (control) or the same diet supplemented with inulin at a level of 4 %. After 6 weeks, the animals were killed and caecum contents and sections of the duodenum and colon were removed. Segments of the genes encoding for the pig divalent metal transporter 1 (DMT1) and duodenal cytochrome-b reductase (Dcytb) were isolated and sequenced. Semi-quantitative RT-PCR analyses were performed to evaluate the expression of DMT1, Dcytb, ferroportin, ferritin, transferrin receptor (TfR) and mucin genes. DMT1, Dcytb, ferroportin, ferritin and TfR mRNA levels in duodenal samples were significantly higher in the inulin group (P ≤ 0·05) compared with the control. In colon, DMT1, TfR and ferritin mRNA levels significantly increased in the inulin group. Additionally, the caecal content microflora was examined using 16S rDNA targeted probes from bacterial DNA. The Lactobacillus and Bifidobacterium populations were significantly increased in the inulin group (P ≤ 0·05) compared with the control group. These results indicate that dietary inulin might trigger an up regulation of genes encoding for Fe transporters in the enterocyte. The specific mechanism for this effect remains to be elucidated.
We report the results of mid- to far-infrared spectroscopic observations of Galactic star-forming regions with ISO, Spitzer, and AKARI. Owing to the high sensitivity of the IRS onboard Spitzer, we detected [Si II] 35 μm, [Fe II] 26 μm, and [Fe III] 23 μm lines widely in low-density star-forming regions, and derived gas-phase Si and Fe abundances as 3–100% and <22%, respectively. With the FTS onboard AKARI, we obtained the spatial distribution ofthe [O III] 88 μm emission in two star-forming regions.
To determine risk factors for neonatal methicillin-resistant Staphylococcus aureus (MRSA) skin and soft-tissue infection in a well-infant nursery.
Design.
Case-control studies.
Setting.
A well-infant nursery in a nonteaching, community hospital.
Methods.
Case infants were newborns in the nursery who were born in the period November 2003 through June 2004 and had onset of MRSA skin and soft-tissue infection within 21 days after discharge from the nursery. Site inspections were conducted. Control infants were randomly selected male infants in the nursery during the outbreak periods. MRSA isolates were characterized with pulsed-field gel electrophoresis.
Results.
Eleven case infants were identified in 2 outbreaks: outbreak 1 occurred from November 18 through December 24, 2003, and outbreak 2 occurred from May 26 through June 5, 2004. All were full-term male infants with pustular-vesicular lesions in the groin. Inspection revealed uncovered circumcision equipment, multiple-dose lidocaine vials, and inadequate hand hygiene practices. In outbreak 1, case infants (n = 6) had a significantly higher mean length of stay than control infants (3.7 vs 2.5 days; P = .01). In outbreak 2, case infants (n = 5) were more likely to have been circumcised in the nursery (OR, undefined [95% CI, 1.7 to undefined]) and to have received lidocaine injections (OR, undefined [95% CI, 2.6 to undefined]). Controlling for length of stay, case infants were more likely to have been circumcised in the nursery (OR, 12.2 [95% CI, 1.5 to undefined]). Pulsed-field gel electrophoresis showed that 7 available isolates were indistinguishable from a community-associated MRSA strain (USA300-0114).
Conclusions.
Newborns in well-infant nurseries are at risk for nosocomial infection with community-associated MRSA strains. Reducing length of stay, improving circumcision and hand hygiene practices, and eliminating use of multiple-dose lidocaine vials should decrease transmission of community-associated MRSA strains in nurseries.
We have started a VLBI monitoring program for Asymptotic Giant Branch (AGB) stars at 22 and 43 GHz as part of a project of the VLBI Exploration of Radio Astrometry (VERA) for precisely obtaining the period-luminosity (PL) relation of Galactic Mira variables. Using accurate distances measured with VERA, we reveal PL relation in the Galaxy based on the absolute magnitudes of the sources. We selected the sources for VLBI monitoring so that they have a good coverage of various pulsation periods. Photometry in the infrared J, H, and K bands for over 600 AGB stars has also started since 2003 with the 1m telescope of Kagoshima University to obtain the pulsation periods and magnitudes. Current analysis of the phase referencing VLBI observations of S Crt shows that the parallax of 2.3±0.2 milliarcsec (mas) corresponds to a distance of 435+41−35 pc. From the infrared monitoring data, pulsation periods and magnitudes in K band for 248 sources were obtained.
We have investigated the flat-band voltage (VFB) shifts of tantalum nitride gate MOS capacitors prepared by two methods. One is CVD-tantalum nitride (CVD-TaN) deposited by the chemical vapor deposition technique using Ta[NC(CH3)2C2H5][N(CH3)2]3 as a precursor, and the other one is sputtered tantalum nitride (sp-TaN) electrodes deposited by reactive DC magnetron sputtering. In the case of the CVD-TaN electrodes, the effective work function estimated from the relationship between VFB and the equivalent oxide thickness (EOT) of the MOS capacitors was about 4.4eV after post metallization annealing (PMA) at 400°C, and shifted to the mid-gap after PMA at 950°C. Moreover, the VFB values of MOS capacitors with sp-TaN electrodes also showed the same behavior after PMA. This shift is mainly dependent on the PMA temperature, regardless of the deposition method used. Similar VFB shifts induced by PMA were also observed in sp-TaN/ Al2O3/ SiO2/ p-Si and sp-TaN/ TaOx/ SiO2/ p-Si capacitors. However, in the case of the sp-TaN/ TaOx/ SiO2/ p-Si capacitors, the VFB shift was also observed when the PDA temperature after the TaOx deposition was 800°C and the PMA temperature after the TaN deposition was only 400°C. These results strongly suggest that this VFB shift caused by the PMA originates from a thin interfacial oxide layer between the TaN gate electrode and the dielectrics. Therefore, the maximum processing temperature after gate electrode deposition is important in order to control the threshold voltage of tantalum nitride gate MOSFETs.
We study the total luminosity function (LF) and the type-specific LF of 7 nearby clusters of galaxies (A1060, S805, A2063, A1736, A1644, A1631, and A754) using the R-band image (1.0 × 0.5 deg2) taken with our mosaic CCD camera mounted on 1-m telescope at the Las Campanas Observatory.
We observed three 0.44 square degree fields centered on the Coma cluster center (Coma-1), about 1 degree SW of the Coma center (Coma-3), and on a control field in SA57 with the mosaic CCD camera at the prime focus of the 4.2-m William Herschel Telescope. We detected 5628, 5020, and 4323 galaxies down to R = 22 mag in Coma-1, Coma-3, and SA57 fields, respectively. We measure the magnitude and color within the variable aperture r90 in which about 90% of the total flux is included. The histograms of (B–R) colors of galaxies are made for four magnitude bins of width ΔR = 2 mag covering 13 < R < 21 mag for each of the three fields. The mean colors and the 1σ scatters of the Coma galaxies are obtained by a histogram subtraction technique (Coma-1/3 minus SA57). We find a very shallow slope of the color-magnitude relation (CMR), Δ(B–R)/ΔR=−0.0037, which indicates nearly a constant (B–R) color over 6 magnitude in 15 < R < 21 mag (−19.5 < MR < −13.5 at Coma cluster). Dwarf galaxies are dominant in this magnitude range, and we conclude that the mean color of dwarf galaxies in the Coma clusters is nearly constant at (B–R) ∼ 1.6–1.7, which is similar to the color of the faint end of giant elliptical galaxies.
At present, the photometric data for clusters at z ≲ 0.2 mainly come from photographic photometry. The lack of CCD data for such clusters is simply due to the fact that no CCD camera had been available until recently that covers the wide extension of clusters within a reasonable amount of observing time. We have developed a large mosaic CCD camera and conducted multicolor imaging observations of z ≲ 0.2 clusters using the 40-inch Swope telescope at Las Campanas Observatory.