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[en] A dorsal acetabular rim (DAR) radiographic view and positioning was devised to visualize the weight-bearing of the acetabulum of dogs for hip evaluation. The DAR view was performed on 250 dogs including 38 breeds. Both males and females were evaluated; ages ranged from six weeks to 11 years. The value of this technique is to evaluate the dorsal rim of the acetabulum for damage and secondary osteoarthritic changes, to correlate palpation of joint capsule laxity and crepitation with the radiographic appearance, to show acetabular filling, and to have an objective reproducible tool for determining whether a hip is normal, dysplastic or injured. This view is recommended as part of the routine procedure for hip examination
[en] Highlights: • Qualitative SWE classification proposed here was significantly better than quantitative SWE parameters. • Qualitative classification proposed here was better than the classification proposed before. • Qualitative classification proposed here could obtain higher specificity without a loss of sensitivity. - Abstract: Objectives: To examine the efficacy of qualitative shear wave elastography (SWE) in the classification and evaluation of solid breast masses, and to compare this method with conventional ultrasonograghy (US), quantitative SWE parameters and qualitative SWE classification proposed before. Methods: From April 2015 to March 2016, 314 consecutive females with 325 breast masses who decided to undergo core needle biopsy and/or surgical biopsy were enrolled. Conventional US and SWE were previously performed in all enrolled subjects. Each mass was classified by two different qualitative classifications. One was established in our study, herein named the Qual1. Qual1 could classify the SWE images into five color patterns by the visual evaluations: Color pattern 1 (homogeneous pattern); Color pattern 2 (comparative homogeneous pattern); Color pattern 3 (irregularly heterogeneous pattern); Color pattern 4 (intralesional echo pattern); and Color pattern 5 (the stiff rim sign pattern). The second qualitative classification was named Qual2 here, and included a four-color overlay pattern classification (Tozaki and Fukuma, Acta Radiologica, 2011). The Breast Imaging Reporting and Data System (BI-RADS) assessment and quantitative SWE parameters were recorded. Diagnostic performances of conventional US, SWE parameters, and combinations of US and SWE parameters were compared. Results: With pathological results as the gold standard, of the 325 examined breast masses, 139 (42.77%) samples were malignant and 186 (57.23%) were benign. The Qual1 showed a higher Az value than the Qual2 and quantitative SWE parameters (all P < 0.05). When applying Qual1 = Color pattern 1 for downgrading and Qual1 = Color pattern 5 for upgrading the BI-RADS categories, we obtained the highest Az value (0.951), and achieved a significantly higher specificity (86.56%, P = 0.002) than that of the US (81.18%) with the same sensitivity (94.96%). Conclusions: The qualitative classification proposed in this study may be representative of SWE parameters and has potential to be relevant assistance in breast mass diagnoses.
[en] Nonvisualization of gallbladder in cholescintigraphy has been established to be a major and reliable finding for acute cholecystitis. A rim of increased pericholecystic hepatic activity (PCHA or Rim sign) in conjunction with gallbladder nonvisualization was reported to be secondary sign of acute cholecystitis. To determine the frequency and significance of the pericholecystic hepatic activity, we evaluated 217 cholescintigram in patients clinically suspected of acute cholecystitis. After brief review of cholescintigraphic findings of acute cholecystitis, the significance of the Rim sign is described. 1) The frequency of the Rim sign in surgically proved acute cholecystitis was 14.9%. 2) The frequency of Rim sign in complicated acute cholecystitis including gallbladder empyema and/or pericholecystic abscess (7/22) and in noncomplicated acute cholecystitis (3/45) was 31.8%, 6.6% respectively. The present study suggests that the Rim sign appear to indicate relatively high incidence of complicated acute cholecystitis and effort should be made observing the presence of the Rim sign in cholescintigraphy.
[en] Resonance ionization is a photophysical process wherein electromagnetic radiation is used to ionize atoms, molecules, transient species, etc., by exciting them through their quantum states. The number of photons required to ionize depends on the species being investigated and energy of the photon. Once a charged particle is produced, it is easy to detect it with high efficiency. With the advent of narrow band high power pulsed and cw tunable dye lasers, it has blossomed into a powerful spectroscopic and analytical technique, commonly known as resonance ionization spectroscopy (RIS)/resonance enhanced multiphoton ionization (REMPI). The alliance of resonance ionization with mass spectrometry has grown into a still more powerful technique, known as resonance ionization mass spectrometry (RIMS), which has made significant contributions in a variety of frontier areas of research and development, such as spectroscopy, chemical dynamics, analytical chemistry, cluster science, surface science, radiochemistry, nuclear physics, biology, environmental science, material science, etc. In this article, we shall describe the application of resonance ionization mass spectrometry to spectroscopy of uranium and chemical dynamics of polyatomic molecules
[en] This communication presents results on a RIMS analysis of thorium. Thorium is of interest for geochronological and geochemical purposes. The measurement of uranium series disequilibrium is a well established and valuable approach for geochronological studies: disequilibrium between 234/238U and 230Th can be used to date samples younger than 350,000 years. Both continuous wave (cw) and pulsed lasers were utilized in this study for resonantly exciting and subsequently ionizing thorium. In the case of the pulsed laser RIMS experiments, two excimer laser-pumped dye lasers were used in conjunction with a 0.4 m time-of-flight mass spectrometer. The cw RIMS experiments used an Ar+ laser-pumped dye laser and a second Ar+ in combination with a single magnetic sector mass spectrometer (NBS 12-90 design). Experiments performed with the pulsed RIMS apparatus were aimed at determining the autoionization state structure and re-determining the ionization potential (IP). By tuning one dye laser to a resonance and scanning the second laser such that the total energy was equal to or above the IP, over 150 autoionization states were determined. The IP was re-determined to be 6.211±.002 eV (50900 ± 20 cm-1). In addition, the typical cross section for ionization of an autoionizing state was determined to be 1 x 10-15 cm2
[en] A compact resonance ionization mass spectrometer is presented. It is presently applied for sensitive and highly selective ultratrace determination of the long-lived radioisotope 41Ca for environmental, biological, and fundamental investigations. The development of coherent multistep resonance ionization enables the realization of experimental detection limits as low as 106 atoms per sample and very high isotopic selectivity above 1012
[en] The first ionization potential of einsteinium (IPEs) was determined by resonance ionization mass spectroscopy (RIMS) using samples with ≤1012 atoms of 254Es (T1/2=276 days). This method is based on the measurement of photoionization thresholds as a function of applied electric field strength, followed by extrapolation to zero field strength to yield IPEs. An atomic beam of Es was created by heating a filament on which einsteinium was electrodeposited from an aqueous solution onto a tantalum backing and covered with titanium metal. Es atoms were ionized via a three-step excitation scheme, and the ions mass-selectively detected in a time-of-flight (TOF) mass spectrometer. The excitation scheme used included a previously unknown EsI level at 32 924.9 cm-1. Furthermore, an autoionizing state at 51 447.3 cm-1 was also found. The first ionization potential of Es was determined to be 6.3676(5) eV (≡51 358(5) cm-1). (orig.)
[en] Negative ion/description chemical ionization mass spectrometry was used in this paper to characterize Lax at sign Cn and Yx at sign Cn fullerenes in soot generated from metal compound-impregnated graphite rods. La at sign C82 and La at sign C80 are extracted by pyridine from the soot, but La at sign C60 and La at sign C70 are not. There are greater abundances of metallofullerenes with the lower ionization potential metal atom in the pyridine extracts. These observations indicate that metallofullerenes exist as ionic complexes with fullerenes (Lax at sign Cn)+Cn-. 16 refs., 4 figs
[en] Purpose: To explore whether superb microvascular imaging (SMI) technology could be helpful for the evaluation of hepatic tumors. Materials and methods: Our institutional review board approved this study, and informed consent was obtained from all of the patients. Twenty-three patients with 29 hepatic tumors were enrolled in our study. The tumors consisted of hemangiomas (n = 15), focal nodular hyperplasias (FNHs) (n = 7), and hepatocellular carcinomas (n = 7). All lesions were pathologically (n = 2) or radiologically (n = 27) confirmed. The mean tumor diameter was 1.9 cm (range, 0.9 cm to 5.0 cm). Using SMI technology, all lesions were scanned and categorized into subgroups according to the flow pattern on the SMI. Results: The hemangiomas exhibited nodular rim patterns (33%) and spotty dot-like patterns (20%), and both of these findings were very specific for the diagnosis of hemangioma. The FNHs exhibited spoke-wheel patterns (43%) and radiating vessel patterns (29%) that were very specific findings for the diagnosis of FNH. The other tumors did not exhibit any specific patterns on SMI. Conclusion: Evaluations of the inner vascularities of hepatic tumors with the SMI technique were feasible, and the SMI features were significantly different between the different types of hepatic tumors. These differences could aid the diagnoses of hepatic tumors with US.