The evolution of electronic (spin and charge) excitations upon carrier doping is an extremely important issue in superconducting layered cuprates and the knowledge of its asymmetry between electron- ...and hole-dopings is still fragmentary. Here we combine X-ray and neutron inelastic scattering measurements to track the doping dependence of both spin and charge excitations in electron-doped materials. Copper L3 resonant inelastic X-ray scattering spectra show that magnetic excitations shift to higher energy upon doping. Their dispersion becomes steeper near the magnetic zone centre and they deeply mix with charge excitations, indicating that electrons acquire a highly itinerant character in the doped metallic state. Moreover, above the magnetic excitations, an additional dispersing feature is observed near the Γ-point, and we ascribe it to particle-hole charge excitations. These properties are in stark contrast with the more localized spin excitations (paramagnons) recently observed in hole-doped compounds even at high doping levels.
Objectives
Sugar consumption has been decreasing in Japan, suggesting higher rates of sucrose‐independent supragingival plaque formation. For developing an in vitro biofilm model of ...sucrose‐independent supragingival plaque, this study aimed to investigate the compositions and functions on contributing to cariogenicity in comparison with sucrose‐dependent biofilm.
Materials and Methods
An in vitro multispecies biofilm containing Actinomyces naeslundii, Streptococcus gordonii, S. mutans, Veillonella parvula and Fusobacterium nucleatum was formed on 24‐well plates in the absence or presence of 1% sucrose. Compositions were assessed by plate culture, scanning electron microscopy and confocal laser scanning microscopy after fluorescent in situ hybridisation or labelling of extracellular polymeric substances (EPS). Functions were assessed by acidogenicity, adherence strength and sensitivities to anticaries agents.
Results
Although both biofilms exhibited a Streptococcus predominant bacterial composition, there were differences in bacterial and EPS compositions; in particular, little glucan EPS was observed in sucrose‐independent biofilm. Compared with sucrose‐dependent biofilm, acidogenicity, adherence strength and antimicrobial resistance of sucrose‐independent biofilm were only slightly lower. However, dextranase degradation was substantially lower in sucrose‐independent biofilm.
Conclusion
Our findings suggest that sucrose‐independent biofilm may have cariogenicity as with sucrose‐dependent biofilm. These in vitro models can help further elucidate plaque‐induced caries aetiology and develop new anticaries agents.
Highlights • Projections from the dorsal peduncular cortex (DP) were examined. • In the prefrontal cortex, only DP projected to the trigeminal caudal subnucleus (Vc). • DP projected only to the ...rostro-dorsomedial part of laminae I/II of Vc (rdm-I/II-Vc). • DP also projected to descending modulation-related brainstem areas. • Mandibular oral nociceptive processing in the rdm-I/II-Vc may be influenced by DP.
Highlights • Rostral part of the rat primary somatosensory cortex (S1) was electrically stimulated to evoke jaw-movements. • Low-frequency long-train (LFLT) stimuli of the rostral S1 evoked ...jaw-movements and activated jaw-opening (JO) muscles. • Most effective sites for LFLT stimuli overlapped those for high-frequency short-train stimuli in the rostralmost S1. • The rostral S1 has projections to the lower brainstem areas including JO and jaw-closing premotoneurons. • Jaw-movements evoked by rostral S1 stimulation are likely controlled by activation of its projections to the premotoneurons.
We performed inelastic neutron scattering measurements on as-grown single crystals of electron-doped Pr1.4-xLa0.6CexCuO4+δ with x = 0, 0.08 and 0.18. We succeeded in observing the spin excitation ...spectra up to 300meV in the all samples. In both parent and electron-doped samples, a magnetic signal was observed at the magnetic zone center (0.5, 0.5) in the low-energy region below 40 meV. In the high-energy region above 100 meV, a double-peak structure reflecting the spin-wave excitation was detected in the constant-energy spectrum for the parent sample, while a single broad peak centered at (0.5, 0.5) was observed for the Ce-doped samples. These results suggest that the dispersion of spin excitation spectra become steeper upon doping. Furthermore, we newly found a drastic reduction of the magnetic intensity with Ce-substitution.
OBJECTIVES To explore the association between the prevalence of hypertension in a Japanese working population and job strain (a combination of low control over work and high psychological demands), ...and to estimate this association in different sociodemographic strata. METHODS From a multicentre community based cohort study of Japanese people, sex specific cross sectional analyses were performed on 3187 men and 3400 women under 65 years of age, all of whom were actively engaged in various occupations throughout Japan. The baseline period was 1992–4. The association between job characteristics—measured with a Japanese version of the Karasek demand-control questionnaire—and the prevalence of hypertension defined by blood pressure and from clinical diagnoses were examined. Adjustments were made for possible confounders. The analyses were repeated for stratified categories of occupational class, educational attainment, and age group. RESULTS In men, the level of job strain (the ratio of psychological job demands to job control) correlated with the prevalence of hypertension. In a multiple logistic regression model, job strain was significantly related to hypertension (odds ratio 1.18; 95% confidence interval 1.05 to 1.32), after adjustment for age, employment (white collarv blue collar), marital status, family history of hypertension, cigarette smoking, alcohol intake, physical activity, and body mass index. The stratified analyses showed significant excess risks in the subordinate groups compared with managers, blue collar workers, less educated workers, and the older age groups. This association was not significant in women. Multiple linear regression analyses, with systolic and diastolic blood pressures as dependent variables, did not show any significant association. CONCLUSIONS The findings provided limited proof that job strain is related to hypertension in Japanese working men. Older men in a lower social class may be more vulnerable to the hypertensive effects of job strain.
The microdosimetric-kinetic (MK) model is one of the models that can describe the fraction of cells surviving after exposure to ionizing radiation. In the MK model, there are specific parameters, k ...and y
D
, where k is an inherent parameter to represent the number of potentially lethal lesions (PLLs) and y
D
indicates the dose-mean lineal energy in keV/μm. Assuming the PLLs to be DNA double-strand breaks (DSBs), the rate equations are derived for evaluating the DSB number in the cell nucleus. In this study, we estimated the ratio of DSBs for two types of photon irradiation (6 MV and 200 kVp X-rays) in Chinese hamster ovary (CHO-K1) cells and human non-small cell lung cancer (H1299) cells by observing the surviving fraction. The estimated ratio was then compared with the ratio of γ-H2AX foci using immunofluorescent staining. For making a comparison of the number of DSBs among a variety of radiation energy cases, we next utilized the survival data in the literature for both cells exposed to other photon types, such as 60Co γ-rays, 137Cs γ-rays and 100 kVp X-rays. The ratio of DSBs based on the MK model with conventional data was consistent with the ratio of γ-H2AX foci numbers, confirming that the γ-H2AX focus is indicative of DSBs. It was also shown that the larger y
D
is, the larger the DSB number is. These results suggest that k and y
D
represent the characteristics of the surviving fraction and the biological effects for photon irradiation.
With many patients living long after microsurgical aneurysm clipping for subarachnoid hemorrhage (SAH) and with the evolution of intravascular procedures as less invasive alternatives, knowledge of ...the long-term results of clipping is becoming important.
Of 412 patients who underwent clipping of ruptured or unruptured cerebral aneurysms at our institution between 1976 and 1994 and who survived >3 years after surgery, 225 patients who were in good general condition and younger than 80 years were offered follow-up angiography to detect newly formed aneurysms. Of the 225, 80 patients (35.6%) agreed to undergo angiography. In addition, 32 patients underwent angiography for new medical indications other than SAH. Therefore, 112 patients underwent angiography, representing a total of 140 clipped aneurysms.
The mean interval from surgery was 9.3 years for all patients and 9.0 years for the clipped aneurysms (range 3 to 21 years). Four aneurysm regrowths were detected of the 140 (2.9%) clipped aneurysms, representing 3 of 125 completely clipped aneurysms, 1 of 14 incompletely clipped aneurysms, and 0 of 1 aneurysm not studied with postoperative angiography. De novo aneurysms were detected in 9 of 112 (8.0%) patients. The annual rate of de novo aneurysm formation was 0.89%.
This study shows that the annual rate of de novo aneurysm formation is relatively high (0.89%) and that the cumulative risk becomes significant after 9 years. In consideration of the fatality rate of SAH, follow-up angiography may be indicated for patients with clipped aneurysms 9 to 10 years after surgery.
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