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Mammary cancer is the second most common tumor worldwide. Small animal mammary neoplasms provide an outstanding model to study cancer in humans, as tumors in both share a similar environment, histopathologic features, and biological behavior. This study aims to investigate the percentage and microscopy of breast tumors in affected dogs and cats; its relationship to breed, age, and sex; and the immunohistochemical expression of estrogen receptor (ER), progesterone receptor (PR), Ki-67, and cytokeratin 8. Twenty-four females (12 dogs and 12 cats) and one male were examined from February 2018 to February 2020. The highest percentage of mammary neoplasia from the highest to the lowest manifested as tubular carcinoma, leiomyosarcoma, fibroadenoma, and cystic papillary carcinoma. The current study reported the second micropapillary invasive carcinoma in a male cat and the third lipid-rich carcinoma in a female cat. Although tubular carcinoma was the most common mammary neoplasm in cats, leiomyosarcoma was the most common in dogs. The immunohistochemical staining revealed diffuse and intense cytoplasmic immunoreactivity for cytokeratin 8 in lipid-rich carcinomas. However, moderate expression of ER in benign tumors and slight to moderate ER expression in malignant mammary lesions were reported. On the contrary, there was a negative PR expression in benign lesion. It could be concluded that a close relationship between ER expression and nuclear antigen Ki-67 was found.
Idiopathic basal ganglia calcification (IBGC) is a neuropathological finding known to manifest motor disturbance, cognitive impairment and psychiatric symptoms. Pathophysiology of psychiatric symptoms, however, remains controversial. Previous biochemical study suggests that dopaminergic impairment is involved in IBGC. We therefore performed positron emission tomography (PET) to elucidate the pre- and postsynaptic dopaminergic function and glucose metabolism in two IBGC patients.
Case 1 is a 44 years old woman presented with disorganized thought, echolalia, verbigeration and parkinsonism. She was administered bitemporal electro-convulsive therapy (ECT). Case 2 is a 35 years old woman with persecutory delusion. Computed tomography showed bilateral symmetric calcification of striatum, globus pallidus and dentate nucei. Other causes of intracranial calcification were excluded. PET scans were obtained using [11C]-labeled 2β-carbomethoxy-3β-(4-flurophenyl)-tropane, [11C]-labeled raclopride and [18F] fluorodeoxyglucose.
The decreased binding potential was severe in bilateral head of caudate nuclei and anterior putamen. In case 1, the decline was also found in posterior putamen. There were widespread decreases of glucose uptake in frontal, temporal and parietal cortices bilaterally in case 1. Significant hypometabolism was observed in the right frontal, temporal and parietal cortices. After the ECT session, the previous areas of significant hypometabolism in the right hemisphere had improved. In case 2, there was no significant change of glucose metabolism in cerebral cortex.
The difference in affected region within basal ganglia might be associated with the diverse clinical pictures in IBGC. Particularly, in the psychiatric manifestation, dopaminergic dysfunction in caudate nucleus and anterior putamen could be participated.
In this paper the Very High Energy (VHE) gamma-ray astronomy program at the University of Adelaide is described. VHE gamma rays with energies above ~5 × 1011eV are observed using the atmospheric Cerenkov technique. Results from the first three years observations at Woomera and the current upgrading of the telecope are described. The CANGAROO project, a collaboration between the University of Adelaide and a number of Japanese institutions, is also introduced.
The present study investigates the indications for transnasal endoscopic surgery in treating post-operative maxillary cysts.
In this retrospective study, the records of 118 patients with post-operative maxillary cysts (88 unilateral and 30 bilateral) consisting of 148 procedures were reviewed.
A transnasal endoscopic approach was performed in 144 lesions (97.3 per cent). A combined endonasal endoscopic and canine fossa (external) approach was performed in 4 of 148 lesions, because the cysts were located distant from the nasal cavity and had a thick bony wall. A ventilation stent was placed in four patients (four cysts) to avoid post-operative meatal antrostomy stenosis. Recurrence was observed in five patients (4.2 per cent), all of whom subsequently underwent transnasal endoscopic revision surgery.
Transnasal endoscopic surgery is an effective treatment for post-operative maxillary cyst with the exception of cysts located distant from the nasal cavity.
To validate a 204-item quantitative FFQ for measurement of nutrient intake in the Adventist Health Study-2 (AHS-2).
Calibration study participants were randomly selected from the AHS-2 cohort by church, and then subject-within-church. Each participant provided two sets of three weighted 24 h dietary recalls and a 204-item FFQ. Race-specific correlation coefficients (r), corrected for attenuation from within-person variation in the recalls, were calculated for selected energy-adjusted macro- and micronutrients.
Adult members of the AHS-2 cohort geographically spread throughout the USA and Canada.
Calibration study participants included 461 blacks of American and Caribbean origin and 550 whites.
Calibration study subjects represented the total cohort very well with respect to demographic variables. Approximately 33 % were males. Whites were older, had higher education and lower BMI compared with blacks. Across fifty-one variables, average deattenuated energy-adjusted validity correlations were 0·60 in whites and 0·52 in blacks. Individual components of protein had validity ranging from 0·40 to 0·68 in blacks and from 0·63 to 0·85 in whites; for total fat and fatty acids, validity ranged from 0·43 to 0·75 in blacks and from 0·46 to 0·77 in whites. Of the eighteen micronutrients assessed, sixteen in blacks and sixteen in whites had deattenuated energy-adjusted correlations ≥0·4, averaging 0·60 and 0·53 in whites and blacks, respectively.
With few exceptions validity coefficients were moderate to high for macronutrients, fatty acids, vitamins, minerals and fibre. We expect to successfully use these data for measurement error correction in analyses of diet and disease risk.
When intrathecally or epidurally administered, α2-adrenoceptor agonists produce potent antinociception by affecting the activity of primary afferent fibres and spinal cord neurons. Recent reports have indicated that in dorsal root ganglion neurons, tetrodotoxin-resistant Na+ channels play important roles in the conduction of nociceptive sensation. We therefore investigated the effects of α2-adrenoceptor agonists on tetrodotoxin-resistant Na+ currents.
Using the whole-cell patch-clamp technique, we recorded tetrodotoxin-resistant Na+ currents from rat dorsal root ganglion neurons.
Both clonidine and dexmedetomidine reduced the peak amplitude of the tetrodotoxin-resistant Na+ current concentration- and use-dependently. The concentration required for a half-maximal effect was significantly lower for dexmedetomidine (58.0 ± 10.2 μmol) than for clonidine (257.2 ± 30.9 μmol) at holding potential −70 mV. The current inhibitions induced by these agonists were not prevented by 1 μmol yohimbine, an α2-adrenoceptor antagonist. Both clonidine and dexmedetomidine shifted the inactivation curve for the tetrodotoxin-resistant Na+ current in the hyperpolarizing direction. The combinations clonidine with lidocaine and dexmedetomidine with lidocaine produced an additive blockade-type interaction on the tetrodotoxin-resistant Na+ current.
The results suggest that a direct inhibition of tetrodotoxin-resistant Na+ channels may contribute to the antinociceptive effects of clonidine and dexmedetomidine when used as additives to regional anaesthesia.
To examine a possible mechanism for the antinociceptive action of the N-methyl-d-aspartate receptor antagonist ifenprodil, we compared its effects with those of ketamine on tetrodotoxin-resistant Na+ channels in rat dorsal root ganglion neurons, which play an important role in the nociceptive pain pathway.
Experiments were performed on dorsal root ganglion neurons from Sprague–Dawley rats, recordings of whole-cell membrane currents being made using patch-clamp technique.
Both drugs blocked tetrodotoxin-resistant Na+ currents dose dependently, their half-maximal inhibitory concentrations being 145 ± 12.1 μmol (ketamine) and 2.6 ± 0.95 μmol (ifenprodil). Ifenprodil shifted the inactivation curve for tetrodotoxin-resistant Na+ channels in the hyperpolarizing direction and shifted the activation curve in the depolarizing direction. Use-dependent blockade of tetrodotoxin-resistant Na+ channels was more marked with ifenprodil than with ketamine. When paired with lidocaine, these drugs produced similar additive inhibitions of tetrodotoxin-resistant Na+ channel activity.
The observed suppressive effects on tetrodotoxin-resistant Na+ channel activity may, at least in part, underlie the antinociceptive effects of these N-methyl-d-aspartate receptor antagonists.
We report the preparation of Cu(In,Ga)Se2 (CIGS) thin-films using the electrodeposited (ED) CuGaSe2 (CGS)/CuInSe2 (CIS) bilayers. CGS/CIS bilayers were prepared on soda-lime glass /Mo substrates to realize the controlled Ga/(Ga+In) ratios and smooth layers of CIGS thin-films. It was found that the composition and morphology of CGS films was highly dependent on the composition of the bath. Crack-free and morphological CGS thin-films were obtained by the addition of supporting electrolyte and brightener. For the morphology and the crystallization of the ED-CIGS films, the best electric charges of CGS and CIS films were 1.0 C and 6.0 C respectively and the films were annealed at 600 oC for 60 min. However, the interface of the ED-CGS/CIS film had some voids and interdiffusions of Ga and In did not take place by annealing. The CIGS solar cell using ED-CGS/CIS films as an absorber exhibited diode behavior.
Self-aligned ultra-high-speed SiGe HBTs were developed by using selective epitaxial growth (SEG) technology. The use of HCl-free SEG, incorporation of C, and optimization of doping profiles significantly improves the performance of the HBT, producing a transistor with a high cutoff frequency of 170 GHz and a maximum oscillation frequency of 204 GHz, for a minimum ECL gate delay time of 4.8 ps. This is applied in a 16:1 MUX with a maximum clock rate of 57 GHz. A 0.13-μm SiGe BiCMOS technology is also realized without any degradation of CMOS due to the high stability of SiGe HBTs. Furthermore, the structure of SiGe HBT is optimized for an emitter scaled down towards 100 nm, mainly through the use of a funnel-shaped emitter electrode to reduce both emitter and base resistances. High-speed operation of a static frequency divider demonstrates the advantage of SiGe HBTs for ultra-high-speed communications systems.
We prepared a SiO2/nanocrystalline Si (nc-Si)/SiO2 sandwich structure. A clear positive shift in C-V and G-V curves due to electrons trapped in nc-Si dots has been observed at room temperature. The peak in conductance around flat band condition indicates that a trap event had occurred where an electron is stored per nc-Si dot. A logarithmic charge loss function is found and this discharging process is independent of the thermal activation mechanism. The longer memory retention time and logarithmic charge loss in the dots are explained by a “built-in” electric field through the tunnel oxide, which varies with time, resulting in a variable tunneling probability. The electric repulsion induced by the built-in electric field hinders the discharging of electrons remained in the dots.
Using very-high-frequency (VHF) plasma decomposition of SiH4 and pulsed gas technique, we have successfully prepared nanocrystalline silicon (nc-Si) quantum dots having average diameter of 8 nm and dispersion of 1 nm. The role of natural oxide is very important. It controls the size of nc-Si dots. Of particular interest is that the oxidation of these dots can be self limited, due to the stress induced near Si/oxide interface, which would allow further reduction of size and improvement in dispersion. This paper deals with the systematic study of oxidation process of nc-Si dots. Nc-Si dots formed in an Ar plasma with SiH4 gas pulses are deposited onto a Pt mesh The dots are then oxidized at 750, 800 and 850°C from 20 minutes to 15 hours. The dimensions of the residual nc-Si and the grown oxide are measured directly from the TEM micrographs and analyzed. For comparison, field oxide is investigated using ellipsometry. Retardation in the oxidation rate of nc-Si is observed. The mechanism of the reduction of oxidation rate in nc-Si is discussed taking into account the effect of stress.
A cold electron emitter has been made from nanocrystalline silicon (nc-Si) dots. Nc-Si dots are formed in the gas phase by very-high-frequency (VHF) plasma enhanced chemical vapor deposition (CVD). Electrons, accelerated by electric field, are ballistically transported through nc-Si and SiO2, then extracted into vacuum. Electron emission efficiency is optimized through varying nc-Si film thickness, surface roughness, and by short thermal oxidation.
The technologies utilizing Fluorinated Silicon Oxide (FSG, k=3.6) and Hydrogen Silsesquioxane (HSQ, k=3.0) have been established for 0.25-μm and 0.18-μm generation ULSIs. However, low-k materials for the next generation ULSIs, which have a dielectric constant of less than 3.0, have not become mature yet. In this paper, we review process integration issues in applying FSG and HSQ, and describe integration results and device performance using Fluorinated Amorphous Carbon (a-C:F, k=2.5) as one of the promising low-k materials for the next generation ULSIs.
A new method for the fabrication of nanocrystalline silicon (nc-Si) in SiH4 plasma with very-highfrequency (VHF; 144MHz) excitation is proposed to increase the deposition rate, to control the size, and to minimize size dispersion of nc-Si. Nanocrystalline silicon is formed in the gas phase of the SiH4 plasma cell by coalescence of radicals. Supplying Ar enhances the nucleation of nc-Si because of high efficiency of SiH4 excitation into SiH2 radicals resulting in the nucleation. The deposition rate is thus increased by a factor of 100 to 1012/cm2.h. At the low flow rate of SiH4, smaller nc-Si with small dispersion is obtained. Moreover, when pulsed-SiH4 is supplied into Ar plasma, the growth of nuclei is limited by the time when SiH4 flows. The size of nc-Si and its dispersion are adjusted by the duration of SiH4 gas pulse.
In this research we estimated the contribution of a major-gene
effect to the control of litter size in
hybrids between two local populations of the house musk shrew (Suncus murinus). Segregation
analysis was performed on the basis of a mixed polygene and major-gene
model. The model
presumes that two parental populations may differ from each other
in gene frequencies and in the
values of polygenic effects but not in the major-gene contribution of the
trait. Moreover, the
peculiarity of the trait – litter size – is taken into account.
This trait is not an individual attribute.
It characterizes the parental couple and may depend on the genotypes of
both parents. Results of
segregation analysis of a large hybrid pedigree of Suncus murinus
indicate that the parental
populations differ in the allele frequency of the major gene (one
population is homozygous, while
the other contains the two alleles in approximately equal proportions)
in the values of average
polygenic effects. Both major-gene and polygenic components are necessary
for the correct
description of litter size inheritance in interracial hybrids of
S. murinus, inasmuch as the exclusion
of either of them leads to a significant drop in likelihood. The
Elston–Stewart criterion also
confirms the Mendelian inheritance of the major gene.
A new method for the formation of nanocrystalline Si (nc-Si) in the SiH4 plasma using pulsed-H2 supply with very-high-frequency (VHF;144MHz) excitation is proposed to control the size of nc-Si. Nanocrystalline Si is formed in the gas phase of SiH4 plasma cell by coalescence of radicals. The principle of size control is based on the separation of nucleation and growth process. Supplying H2 into a SiH4 plasma enhances nucleation of nc-Si and suppresses growth rate of nc-Si. The nucleated nc-Si grows larger in a SiH4 plasma during the off state of the H2 supply. As the newly supplied H2 forces nc-Si grown in the previous cycle out of the plasma cell into the deposition chamber, the next nucleation of nc-Si is enhanced simultaneously. Using this method, we fabricated 8 nm-diameter nc-Si with small dispersion (±1 nm) successfully.
The Collaboration of Australia and Nippon for a GAmma Ray Observatory in the Outback operates two large telescopes at Woomera (South Australia), which detect the Čerenkov light images produced in the atmosphere by electronpositron cascades initiated by very high energy (~1 TeV or 1012 eV) gamma rays. These gamma rays arise from a different mechanism than at EGRET energies: inverse Compton (IC) emission from relativistic electrons.
The spoke-like images are recorded by a multi-pixel camera which facilitates the rejection of the large numbers of oblique and ragged cosmic ray images. A field of view ~3.5° is required. The Australian team operates a triple 4 m diameter mirror telescope, BIGRAT, with a 37 photomultiplier tube camera and energy threshold 600 GeV. The Japanese operate a single, highly accurate 3.8 m diameter f/1 telescope and high resolution 256 photomultipler tube camera. In 1998 a new 7 m telescope is planned for Woomera with a design threshold ~;200GeV.
We have proposed digital plasma processing for the fabrication of silicon quantum dots with grain size less than l0nm. By using the pulsed gas supply of SiH4 and H2 in the very-high frequency (VHF) plasma, we have clarified the role of atomic hydrogen in the nucleation, crystallization of nanocrystalline Si (nc-Si) as well as in the selective etching of amorphous Si to nc-Si. Recently, we have prepared nc-Si by employing an ultra-high-vacuum (UHV) chamber equipped with VHF plasma cells of SiH4 and H2. Flux rate of Si cluster depends significantly on the pressure of the plasma cell and VHF power. Spherical shaped nc-Si clusters less than 6nm in diameter have been observed by transmission electron microscopy (TEM). Infrared absorption measurements have clarified that the surface of nc-Si is covered by hydrogen. In an attempt to control the position of nuclei, we have prepared nc-Si on SiO2 with micro trenches, 40nm wide and 20nm deep, fabricated by electron beam exposure and electron cyclotron resonance (ECR) etching. It has been revealed by TEM observation that nc-Si are formed preferentially along micro trenches.
SI GaAs crystals submitted to single- or multi-step, ingot-or wafer-annealing are investigated using photoluminescence (PL) and photoacoustic spectroscopy (PA). The near-band-edge PL transitions are well resolved, with a neutral acceptor-bound exciton recombination displayed as a split doublet. The improvement induced by wafer-annealing is illustrated by the absence of additional defect-related transitions found after ingot-annealing. For the room temperature PA measurements, the intensity of a peak occuring at 1.39 eV is shown to lead to an estimation of the arsenic micro-defect density as evaluated by AB etching. The 1.39 eV PA band is also asserted to be the non-radiative recombination path of a 1.482 eV band found in the low-temperature PL spectra.