Distinct Kondo Screening Behaviors in Heavy Fermion Filled Skutterudites with 4f

CeOs_{4}Sb_{12} (COS) and PrOs_{4}Sb_{12} (POS) are two representative compounds that provide the ideal vantage point to systematically study the physics of multi-f-electron systems. COS with Ce 4f^{1}, and POS with Pr 4f^{2} configurations show distinct properties of Kondo insulating and heavy fermion superconductivity, respectively. We unveiled the underlying microscopic origin by angle-resolved photoemission spectroscopy studies. Their eV-scale band structure matches well, representing the common characters of conduction electrons in ROs_{4}Sb_{12} systems (R=rare earth). However, f electrons interact differently with conduction electrons in COS and POS. Strong hybridization between conduction electrons and f electrons is observed in COS with band dependent hybridization gaps, and the development of a Kondo insulating state is directly revealed. Although the ground state of POS is a singlet, finite but incoherent hybridization exists, which can be explained by the Kondo scattering with the thermally excited triplet crystalline electric field state. Our results help us to understand the intriguing properties in COS and POS, and provide a clean demonstration of the microscopic differences in heavy fermion systems with 4f^{1} and 4f^{2} configurations.

[Development and performance test of the environment scale of unintentional injury in the home for children aged 0-6 years old in urban area of China].

Objective: To develop the environment scale of unintentional injury in the home for children aged 0-6 years living in urban area of China, and test its validity and reliability. Methods: The content of the environment scale was established through the literature review, expert consultation and pilot study. A total of 1 104 children aged 0-6 years in urban area of Changsha were enrolled in this study by using a multi-stage stratified cluster random sampling method. The questionnaire was used to collect the basic information of children, the incidence of unintentional injury and the status of home environment. The reliability of the scale was tested by using Cronbach's α coefficient and split-half reliability coefficient. The content validity and construct validity were tested by using Pearson correlation analysis and factor analysis. All children were divided into two groups according to the incidence of unintentional injury in the home and the discrimination validity of the scale was tested by using t-test. Results: The scale had 54 items in 6 dimensions. The number of eligible questionnaires was 1 074, including 554 (51.6%) from boys and 519 (48.3%) from children under 3 years old. The incidence rate of unintentional injury and in-home injury was 18.34% (197 children) and 10.71% (115 children). The internal consistency reliability (Cronbach's α) coefficient for the scale was 0.87 and the split-efficacy reliability coefficient was 0.82, both meeting the standard of reliability above 0.70. The Pearson correlation coefficient between each dimension and the whole scale ranged from 0.53 to 0.84 (all P values <0.001). The common factor cumulative variance contribution rate of the scale was 58.34%. There were 54 items with factor loadings greater than 0.30. The root mean square error of approximation, comparative fit index and goodness-of-fit index were 0.07, 0.61 and 0.71, respectively. The score of scale in children with injury was significantly higher than that in children without injury (P=0.022). Conclusion: The validity and reliability of the environment scale for unintentional injury in the home for children aged 0-6 years old in the urban area of China are good.

Strong band renormalization and emergent ferromagnetism induced by electron-antiferromagnetic-magnon coupling.

The interactions between electrons and antiferromagnetic magnons (AFMMs) are important for a large class of correlated materials. For example, they are the most plausible pairing glues in high-temperature superconductors, such as cuprates and iron-based superconductors. However, unlike electron-phonon interactions (EPIs), clear-cut observations regarding how electron-AFMM interactions (EAIs) affect the band structure are still lacking. Consequently, critical information on the EAIs, such as its strength and doping dependence, remains elusive. Here we directly observe that EAIs induce a kink structure in the band dispersion of Ba1-xKxMn2As2, and subsequently unveil several key characteristics of EAIs. We found that the coupling constant of EAIs can be as large as 5.4, and it shows strong doping dependence and temperature dependence, all in stark contrast to the behaviors of EPIs. The colossal renormalization of electron bands by EAIs enhances the density of states at Fermi energy, which is likely driving the emergent ferromagnetic state in Ba1-xKxMn2As2 through a Stoner-like mechanism with mixed itinerant-local character. Our results expand the current knowledge of EAIs, which may facilitate the further understanding of many correlated materials where EAIs play a critical role.

Evidence of cooperative effect on the enhanced superconducting transition temperature at the FeSe/SrTiO3 interface.

At the interface between monolayer FeSe films and SrTiO3 substrates the superconducting transition temperature (Tc) is unexpectedly high, triggering a surge of excitement. The mechanism for the Tc enhancement has been the central question, as it may present a new strategy for seeking out higher Tc materials. To reveal this enigmatic mechanism, by combining advances in high quality interface growth, 16O [Formula: see text] 18O isotope substitution, and extensive data from angle resolved photoemission spectroscopy, we provide striking evidence that the high Tc in FeSe/SrTiO3 is the cooperative effect of the intrinsic pairing mechanism in the FeSe and interactions between the FeSe electrons and SrTiO3 phonons. Furthermore, our results point to the promising prospect that similar cooperation between different Cooper pairing channels may be a general framework to understand and design high-temperature superconductors.

FISH analysis of an AML-M5a with segmental rearrangements involving 11q23-MLL region.

A 66-year-old man was diagnosed 10 years ago with thrombocytosis and treated with hydroxyurea. Recently, his condition deteriorated and he was found to have 68% blasts in the blood and AML-M5a. Conventional cytogenetic analysis and fluorescence in situ hybridization studies using 11-painting and MLL probes showed that chromosome 11 had duplications or triplications; the markers were also derived from the chromosome 11-MLL region. Therefore, we have demonstrated segmental rearrangement of chromosome 11 involving the MLL region resulting in multiple copies of the MLL gene.

DNA content of head and neck squamous carcinoma by flow and image cytometry.

OBJECTIVE: To compare the measurement of quantitative DNA in squamous cell carcinoma of the head and neck by flow cytometry and image cytometry. DESIGN: Comparison of image cytometry to the more commonly used flow cytometry using paraffin-embedded tissues. SETTING: University of California, Davis Medical Center, Sacramento. A 472-bed university teaching hospital. PATIENTS: Records of 26 patients with squamous cell carcinoma of the tongue, base of tongue, and larynx were obtained from the case files of an otolaryngologist-head and neck surgeon. They were reviewed for staging and follow-up. RESULTS: We demonstrated a 96% concordance rate between the methods. A solitary discrepant case was aneuploid by image cytometry and diploid by flow cytometry. The specimen involved tumor infiltrated by lymphocytes that may have masked the aneuploid population to measurement by flow cytometry. Quantitative DNA analysis correlated moderately well with tumor grade, tumor stage, and patient outcome with a minimum of 6 years of follow-up. All patients with diploid tumors were long-term survivors. CONCLUSIONS: Both methods provide accurate quantitative DNA analyses in squamous cell carcinoma of the head and neck. The methods are highly correlative and yield similar predictive data regarding tumor behavior and prognosis.

Homotransplantation of adrenal gland.

Eight patients with Addison's disease or Cushing's syndrome received adrenal homograft for 9 times after total adrenalectomy. All patients were followed up for 1 to 5 years. Symptoms and signs were improved without the supplement of steroids. The grafts showed satisfactory endocrinal functions in the recipients, but the grafts were dead in two patients 2 and 4 years after operation respectively. One of the two patients received the second homograft with good result. Single perfusion and ice-storage method of the all-adrenal gland and their clinical results were also presented.

[Familial pheocromocytoma. Report of 4 families].

Twelve patients with pheochromocytomas were found in members of 4 families in the recent 25 years. Nine of them were treated and confirmed surgically. Follow-up showed that 50% of the members were found to suffer from pheochromocytomas. Six of the 9 patients had bilateral and multiple tumors. The tumors developed in the adrenal glands and benign in nature. Three of the 12 patients were associated with thyroid tumors. Peripheral leukocyte chromosomes were studied in two families. Chromosomal analysis showed no evidence of marker on the 15th chromosomal pair. These findings were not consistent with the previous results. Tumor tissue contents of catecholamine were determined in 4 familial tumors and 14 sporadic pheochromocytomas. Familial pheochromocytomas tissue contained significantly higher norepinephrine and epinephrine than the sporadic tumors.

Alteration in regional brain catecholamines during and after acute hemorrhage in the rat.

Using high-performance liquid chromatography (HPLC), we carried out a simultaneous assay of norepinephrine (NE), epinephrine (E), and dopamine (DA) in specific brain regions before and at 5 min, 30 min, 1 hr, 2 hr, and 24 hr following acute hemorrhage in the rat. Thirty-six awake male Sprague-Dawley rats were subjected to rapid fixed-volume hemorrhage (8.5 ml/300 g) over 5 min. In the hypothalamus, concentrations of NE and E fell markedly and significantly by 5 min posthemorrhage (P < 0.001), while hypothalamic DA concentrations fell gradually to reach a nadir by 2 hr (P < 0.005). Hypothalamic concentrations of all three catecholamines remained significantly reduced up to 24 hr posthemorrhage. Dopamine concentrations in the medulla increased transiently, while striatal DA concentrations fell following hemorrhage to reach a nadir by 2 hr (P < 0.001). By 2 hr posthemorrhage, NE concentrations in both cortex and medulla were significantly decreased (P < 0.01 and P < 0.005, respectively), with cortical NE levels remaining significantly depressed for up to 24 hr. These results suggest that regional and prolonged changes occur in central catecholaminergic systems following acute, uncompensated hemorrhage. It is possible that these changes in the central nervous system contribute to the cardiovascular dysfunction observed following hemorrhage.

Inefficacy of extracorporeal photochemotherapy in the treatment of B-cell chronic lymphocytic leukemia: preliminary results.

Because extracorporeal photopheresis has been shown to be clinically effective in Sezary syndrome, a disease characterized by a circulating malignant clone, we initiated a pilot study of its use in B-cell chronic lymphocytic leukemia (B-CLL) to see if it could be similarly effective. We treated three patients with Rai stage III and IV B-CLL with photopheresis (3 consecutive days a week every 3 weeks) and followed serial clinical and immunologic parameters. While we noted no major toxicity, there was neither clinical response to treatment nor marked improvement in white counts or mitogen assays. We conclude that photopheresis was not effective in inducing remission in this pilot study of advanced stage B-CLL patients.