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Background. Middle-ear carcinoid tumour is a rare malignant tumour with an indolent course occasionally causing regional or distant metastasis. This paper presents a case of middle-ear carcinoid tumour metastasising to the parapharyngeal space and the parotid gland 20 years after the first surgery.
Case report. A 35-year-old woman who underwent multiple tympanomastoidectomies for middle-ear carcinoid presented with tumours of both the parapharyngeal space and parotid gland, detected by regular imaging. Based on the clinical course, metastatic relapse of middle-ear carcinoid was suspected. This was treated with subtotal parotidectomy with elective neck dissection (levels II and III), leading to the pathological diagnosis of carcinoid tumour. A cervico-parotid approach was selected to avoid complications associated with parapharyngeal space tumour removal. Transient facial palsy (House–Brackmann grade III) occurred, which completely recovered two months after surgery.
Conclusion. Awareness of parapharyngeal space tumours possibly caused by metastasis from a middle-ear tumour is necessary.
Sleep restriction has adverse effects on performance and neurobehavioral function. However, the mechanism of impaired performance and neurobehavioral function has not been studied yet.
We examined the effect of insufficient sleep on cerebral blood flow and cognitive function in 8 healthy adults (mean age 22.4 years).
All participants were in bed for 8 h (sufficient sleep), and for < 4 h (insufficient sleep). The oxyhemoglobin (oxyHb) level by a word fluency task was measured with a near-infrared spectroscopy recorder on the morning following sufficient and insufficient sleep periods. Wisconsin card sorting test (WCST), continuous performance test (CPT) and N-back test were evaluated on the same days.
The peak oxyHb level was significantly lower in the left and right frontal lobes after insufficient sleep than after sufficient sleep (left: 0.25 ± 0.10 vs. 0.70 ± 0.29 mmol, P < 0.05; right: 0.23 ± 0.13 vs. 0.73 ± 0.22 mmol, P < 0.05). There was no significant difference in the number of words generated during the word fluency task between sufficient and insufficient sleep states. The percentage of correct responses on CPT after insufficient sleep was significantly lower than that after sufficient sleep (86.6 ± 10.2 vs. 96.0 ± 4.9%, P < 0.05). The reaction time of WCST was significantly longer after insufficient sleep than after sufficient sleep (76.6 ± 13.4 vs. 70.6 ± 16.2 sec, P < 0.05).
One night sleep restriction decreased the concentration changes of oxyHb in brain tissue, leading to impaired cognitive function.
Chronic sleep restriction results from a number of factors; medical condition and social demands, and has adverse effects on daytime function, such as cognitive function and driving performance. We demonstrated that the acute sleep restriction (time in bed < 4 h/night) impaired cortical oxygenation response during word fluency task.
We examined the chronic effect of insufficient sleep on cerebral blood flow and cognitive function.
Ten healthy adults (mean age 19.0 years, mean BMI 22.5 kg/m2) were enrolled in this study. All participants spent > or = 8 h/night in bed prior to study day (sufficient sleep), followed by < 4 h/night in bed for 3 days (insufficient sleep1, 2 and 3). The oxyhemoglobin (oxyHb) level by a word fluency task was measured with a near-infrared spectroscopy recorder on the morning following sufficient and insufficient sleep 1 and 3. Wisconsin card sorting test (WCST), continuous performance test -identical pairs version (CPT-IP) and 2-back test were evaluated on the same day.
The peak oxyHb during the word fluency task was significantly reduced after insufficient sleep 1 and 3 than that after sufficient sleep. The percentage of correct responses on CPT-IP and 2- back test after insufficient sleep 3 were lower than those after sufficient sleep, though there were no significant differences on those. WCST did not significantly differ among insufficient sleep 1 and 3 and sufficient sleep.
The chronic sleep restriction reduced cortical oxygenation response, and might result in cognitive performance impairment.
The implementation of advanced multi-level modulation schemes such as quadrature phase-shift keying (QPSK) in contrast to the conventional on–off keying is crucial to further boost the terahertz (THz) communications speed. Thereby, carrier phase noise reduction in the THz range is one of the key goals that need to be urgently achieved. In this paper, the photonic-based THz sources and the phase noise problem are briefly summarized. Then, a low phase-noise photonic source based on the stimulated Brillouin scattering (SBS) optical fiber cavity is first applied for a 300-GHz-band QPSK wireless communication link. The highest data rate at forward-error-correction limited condition was 15 Gbaud utilizing the SBS-based photonic source with a small transmit power of ~ −36 dBm. Its transmission characteristics are evaluated and compared with the conventional optical frequency comb generator (OFCG)-based source at 5 Gbaud. The proposed SBS-based photonic source has been proven to offer better performances than the OFCG-based source with respect to the phase noise, optical carrier to noise ratio, and bit error rate in communications.
Toca 511 (vocimagene amiretrorepvec) is an investigational, conditionally lytic, retroviral replicating vector (RRV). RRVs selectively infect cancer cells due to innate and adaptive immune response defects in cancers that allow virus replication, and the requirement for cell division for virus integration into the genome. Toca 511 spreads through tumors, stably delivering an optimized yeast cytosine deaminase gene that converts the prodrug Toca FC (investigational, extended-release 5-FC) into 5-FU within the tumor microenvironment. 5-FU kills infected dividing cancer cells and surrounding tumor, myeloid derived suppressor cells, and tumor associated macrophages, resulting in long-term tumor immunity in preclinical models. Data from a Phase 1 resection trial showed six durable CRs and extended mOS compared to historical controls. The FDA granted Breakthrough Therapy Designation for Toca 511 & Toca FC in the treatment of patients with rHGG. Toca 5 is an international, randomized, open-label Phase 3 trial (NCT02414165) of Toca 511 & Toca FC versus SOC in patients undergoing resection for first or second recurrence of rHGG. Patients will be stratified by IDH1 status, KPS, and geographic region. Primary endpoint is OS, and secondary endpoints are durable response rate, durable clinical benefit rate, duration of durable response, and 12-month survival rate. Key inclusion criteria are histologically proven GBM or AA, tumor size ≥1cm and ≤5cm, and KPS ≥70. Immune monitoring and molecular profiling will be performed. Approximately 380 patients will be randomized. An IDMC is commissioned to review the safety and efficacy data which includes 2 interim analyses. Enrollment is ongoing.
US public health laboratories began reporting Escherichia coli O157 isolates to CDC in 1996. We describe temporal and geographical patterns of isolates reported from 1996 to 2011 and demographics of persons whose specimens yielded isolates. We calculated annual E. coli O157 isolation rates/100 000 persons by patient's state of residence, county of residence, age, and sex using census data. The average annual isolation rate was 0·84. The average isolation rate in northern states (1·52) was higher than in southern states (0·43). Counties with ⩾76% rural population had a lower isolation rate (0·67) than counties with ⩽25%, 26–50%, and 51–75% rural populations (0·81, 0·92, and 0·81, respectively). The highest isolation rate (3·19) was in children aged 1–4 years. Infections were seasonal with 49% of isolates collected during July to September. Research into reasons for higher incidence in northern states and for seasonality could guide strategies to prevent illnesses.
A multistate outbreak of Escherichia coli O157:H7 infections occurred in the USA in November–December 2006 in patrons of restaurant chain A. We identified 77 cases with chain A exposure in four states – Delaware, New Jersey, New York, and Pennsylvania. Fifty-one (66%) patients were hospitalized, and seven (9%) developed haemolytic uraemic syndrome; none died. In a matched analysis controlling for age in 31 cases and 55 controls, illness was associated with consumption of shredded iceberg lettuce [matched odds ratio (mOR) 8·0, 95% confidence interval (CI) 1·1–348·1] and shredded cheddar cheese (mOR 6·2, CI 1·7–33·7). Lettuce, an uncooked ingredient, was more commonly consumed (97% of patients) than cheddar cheese (84%) and a single source supplied all affected restaurants. A single source of cheese could not explain the regional distribution of outbreak cases. The outbreak highlights challenges in conducting rapid multistate investigations and the importance of incorporating epidemiological study results with other investigative findings.
Infection by Listeria monocytogenes in pregnant women may result in fetal loss or invasive disease in the newborn. We examined listeriosis cases reported through the U.S. Listeria Initiative during 2004–2007. Cases were classified as pregnancy-associated if illness occurred in a pregnant woman or an infant aged <28 days. Of 758 reported Listeria cases, 128 (16·9%) were pregnancy-associated. Maternal infection resulted in four neonatal deaths and 26 (20·3%) fetal losses. Invasive illnesses in newborns (n=85) were meningitis (32·9%) and sepsis (36·5%). Pregnant women with Listeria were more likely to report Hispanic ethnicity (52·8% vs. 25·6%, respectively; OR 3·3 95% CI 2·2–4·8) than mothers giving live birth in the USA during 2005 and were more likely to report consumption of Mexican-style cheese (OR 2·6, 95% CI 1·6–4·2) than were non-pregnant patients with Listeria infection. Pregnant woman comprised a considerable proportion of reported listeriosis cases. Further declines in pregnancy-associated listeriosis will require education about avoiding high-risk foods, and continued regulatory and industry efforts to decrease Listeria in foods.
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.
“Stand-support sintering”, that is supporting the load of the sinter cake with bars or
plates attached to pallets, has been developed and applied practically to the sintering
machines in Kimitsu works, Nippon Steel. The stands start to support the load of the sinter
cake just after the top layer is melted and starts to solidify. Shrinkage is stopped
and the gas flow rate is increased when the stands start to support the load of the
sinter cake. It was found that sintering time was shortened and productivity was improved in
actual sintering machines.
We discuss the properties of the very energetic Type Ic supernovae (SNe Ic) 1998bw and 1997ef, and of Type IIn supernova (SN IIn) 1997cy. SNe Ic 1998bw and 1997ef are characterized by their large luminosity and very broad spectral features. Their observed properties can be explained if they are very energetic SN explosions (EK ≳ 1 × 1052 erg), originating probably from the core collapse of the bare C+O cores of massive stars (~ 30–40M⊙). At late times, both the light curve and the spectra suggest that the explosion may have been asymmetric; this may help us understand the claimed connection with GRBs. Type IIn SN 1997cy is even more luminous than SN 998bw, and the light curve declines more slowly than the 56Co decay. We model such a light curve with circumstellar interaction, which requires the explosion energy of ~ 5 × 1052 erg. Because these kinetic energies of explosion are much larger than in normal core-collapse SNe, we call objects like these SNe “hypernovae”.
T. Shigeyama, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
K. Iwamoto, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
I. Hachisu, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
K. Nomoto, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
H. Saio, Tohoku University, Sendai 980, Japan
We calculate a nonlinear growth of the Rayleigh-Taylor instability in the exploding red supergiant stars with a two-dimensional hydrodynamical code, and examine how the extent of mixing depends on the progenitor's core mass and the envelope mass. The results are compared with the observations of type II-P supernovae and the recent type II-b supernova 1993J.
Large scale mixing in supernova ejecta has been indicated in spectroscopic and photometric observations of various types of supernovae. This has stimulated 2D and 3D hydrodynamical calculations of the Rayleigh-Taylor (R-T) instabilities during supernova explosions for SN 1987A (Arnett et al. 1989; Hachisu et al. 1990, 1992; Fryxell et al. 1991; Müller et al. 1991; Den et al. 1990; Yamada et al. 1990; Yamada & Sato 1991; Herant & Benz 1991, 1992), type Ib/Ic supernovae (Hachisu et al. 1991, 1994a), type II-P supernovae (Herant & Woosley 1994; Hachisu et al. 1994b), and the type II-b supernova 1993J (Iwamoto et al. 1994). In particular, Hachisu et al. (1991, 1994a) found that development of the R-T instabilities depend sensitively on the presupernova structure, so that the comparison between hydrodynamical simulations and observations can provide a new clue to the understanding of supernova progenitors, their structure, and the explosion mechanism.
In the present paper, we follow a nonlinear growth of the R-T instabilities in the exploding red supergiant stars, i.e., type II-P and II-b supernovae. We find that the extent of mixing depends on the core mass and the envelope mass of red supergiants.
K. Nomoto, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
H. Yamaoka, Kyushu University, Fukuoka 810, Japan,
T. Shigeyama, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan,
K. Iwamoto, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan
We summarize various explosion models of Type Ia supernovae and their nucleosynthesis features for both Chandrasekhar and sub-Chandrasekhar mass white dwarf models. These models provide different predictions of the photometric and spectroscopic variations among Type Ia supernovae, which are compared with observations. Some attempts to model the peculiar SNe 1991T and 1991bg are shown.
Type I supernovae (SNe I) are spectroscopically defined by the absence of hydrogen in their optical spectra and further subclassified into Ia, Ib, and Ic (see, e.g., Branch et al. 1991). The early–time optical spectra of SNe Ia are characterized by the presence of a deep absorption Si II line near 6150 Å, and their late–time spectra are dominated by strong blends of Fe emission lines (Harkness & Wheeler 1990). Relatively uniform light curves and spectral evolution of SNe Ia have led to the use of SNe Ia as a standard candle to determine cosmological parameters, H0 and q0 (Branch & Tammann 1992).
Recent attention has been paid to variations of light curves and spectra among SNe Ia. SNe 1991T and 1991bg have clearly revealed the presence of both spectroscopically and photometrically peculiar SNe Ia. Photometrically, maximum brightness and the decline rate of the light curve show some systematic variations, where SNe 1991T and 1991bg are situated at the two extreme ends of the brighter–slower tendency (Phillips 1993; Branch et al. 1993). Spectroscopically, the pre-maximum spectra of SNe Ia reveal a significant variation of the composition and expansion velocities of the outermost layers, whereas the post-maximum spectra are relatively uniform except for SN 1991bg.
Supernovae are classified as type I and type II and further subdivided into Ia, Ib, Ic, II-P, II-L, and IIb. The origin of this observational diversity has not been well understood. The recent nearby supernovae SN 1993J and SN 1994I have provided particularly useful material to clarify the supernova — progenitor connection. For a progenitor of type IIb supernova 1993J, we propose that merging of two stars in a close binary is responsible for the formation of a thin H-rich envelope. As a progenitor of type Ic supernova 1994I, we propose a bare C+O star that has lost both its H and He envelope after a common-envelope phase. By generalizing these scenarios, we show that common-envelope evolution in massive close binary stars leads to various degrees of stripping off of the envelope of a massive star. This naturally leads to an explanation of the origin of type II-L, IIn, IIb, Ib, and Ic in a unified manner. The binary hypothesis to explain the diversity of supernovae can be substantiated with new information on SN IIb 1993J and SN Ic 1994I. Model light curves are compared with observations. Since extensive mass loss is essential for the binary scenario, circumstellar interactions are examined for comparison with X-ray observations.
Mixtures of mono- and diacrylates showing a nematic phase were polymerized in an electric field. The orientation of chromophores in the thin films depended on the direction of dipole moment as well as the polymerization conversion of the liquid crystalline monomers.
Bioactive ORMOSILS (Organically Modified Silicates) were synthesized by a sol-gel method, with tetraethoxysilane (TEOS) and polydimethylsiloxane (PDMS). Ca(II) ions were incorporated into the ormosil monoliths by addition of calcium nitrate. The synthesized samples were examined on the bioactivity by the use of a simulated body fluid (the Kokubo solution). The Ca(II) containing ormosils were bioactive that deposited apatite during soaking in the Kokubo solution. The dissolution of Ca(II) from the sample favored the formation of the hydrated silica, which gave nucleation sites for apatite, while the effect of dissolved Ca(II) ions to increase the degree of supersaturation in the fluid could not be neglected.
We summarize various explosion models of Type la supernovae and their nucleosynthesis features for both Chandrasekhar and sub-Chandrasekhar mass white dwarf models. These models provide different predictions of the photometric and spectroscopic variations among Type la supernovae, which are compared with observations. Some attempts to model the peculiar SNe 1991T and 1991bg are shown.
We have demonstrated the influence of surface microroughness on the electrical characteristics of MOS devices and investigated the influence of wafer's manufacturing methods, such as Czochralski(Cz), floating-zone(FZ), and epitaxial(Epi) silicon wafers, on the susceptibility to the surface microroughness when some chemical treatment was performed. As a result, it was found that Cz and FZ wafers are very susceptible to the surface microroughness and the amount of the vacancy of Epi wafer is much smaller than that of another wafers. It was also demonstrated that the electrical characteristics of very thin gate oxide films are strongly influenced by the silicon substrate quality. Epi wafer is a strong candidate for fablication of highly-reliable devices on 300mm wafers.
We calculate a nonlinear growth of the Rayleigh-Taylor instability in the exploding red supergiant stars with a two-dimensional hydrodynamical code, and examine how the extent of mixing depends on the progenitor's core mass and the envelope mass. The results are compared with the observations of type II-P supernovae and the recent type Il-b supernova 1993J.
Microstructure evolution was studied in silicon nitride ceramics by a novel characterization method, and its relevance to the strength was discussed. The characterization method involves an immersion liquid for making green and partially sintered bodies transparent, and a subsequent direct optical microscopic examination. Granules for compaction process were prepared with the spray-drying process and were found to contain pores or deep dimples. Green bodies formed by CIP with these granules contain regularly arrayed pores at the center of granules and also crack-like voids at the boundaries of granules. These pores were preserved in the sintering process and resulted in large pores in the sintered body. They behave as fracture origin in ceramics and reduce the fracture strength. The Weibull modulus was high due to the presence of uniformly distributed pores.