251 research outputs found

    Nodeless superconductivity in Lu5-xRh6Sn18+x with broken time reversal symmetry

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    Evidence for broken time reversal symmetry (TRS) has been found in the superconducting states of the R 5 Rh 6 Sn 18 ( R = Sc , Y, Lu) compounds with a centrosymmetric caged crystal structure, but the origin of this phenomenon is unresolved. Here, we report neutron diffraction measurements of single crystals with R = Lu , as well as measurements of the temperature dependence of the magnetic penetration depth using a self-induced tunnel-diode-oscillator (TDO)-based technique, together with band structure calculations using density functional theory. Neutron diffraction measurements reveal that the system crystallizes in a tetragonal caged structure, and that one of the nominal Lu sites in the Lu 5 Rh 6 Sn 18 structure is occupied by Sn, yielding a composition Lu 5 − x Rh 6 Sn 18 + x ( x = 1 ). The low temperature penetration depth shift Δ λ ( T ) exhibits an exponential temperature dependence below around 0.3 T c , giving clear evidence for fully gapped superconductivity. The derived superfluid density is reasonably well accounted for by a single-gap s -wave model, whereas agreement cannot be found for models of TRS breaking states with two-component order parameters. Moreover, band structure calculations reveal multiple bands crossing the Fermi level, and indicate that the aforementioned TRS breaking states would be expected to have nodes on the Fermi surface, in contrast to the observations

    A review of physical supply and EROI of fossil fuels in China

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    This paper reviews China’s future fossil fuel supply from the perspectives of physical output and net energy output. Comprehensive analyses of physical output of fossil fuels suggest that China’s total oil production will likely reach its peak, at about 230 Mt/year (or 9.6 EJ/year), in 2018; its total gas production will peak at around 350 Bcm/year (or 13.6 EJ/year) in 2040, while coal production will peak at about 4400 Mt/year (or 91.9 EJ/year) around 2020 or so. In terms of the forecast production of these fuels, there are significant differences among current studies. These differences can be mainly explained by different ultimately recoverable resources assumptions, the nature of the models used, and differences in the historical production data. Due to the future constraints on fossil fuels production, a large gap is projected to grow between domestic supply and demand, which will need to be met by increasing imports. Net energy analyses show that both coal and oil and gas production show a steady declining trend of EROI (energy return on investment) due to the depletion of shallow-buried coal resources and conventional oil and gas resources, which is generally consistent with the approaching peaks of physical production of fossil fuels. The peaks of fossil fuels production, coupled with the decline in EROI ratios, are likely to challenge the sustainable development of Chinese society unless new abundant energy resources with high EROI values can be found

    The Zinc Dyshomeostasis Hypothesis of Alzheimer's Disease

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    Alzheimer's disease (AD) is the most common form of dementia in the elderly. Hallmark AD neuropathology includes extracellular amyloid plaques composed largely of the amyloid-β protein (Aβ), intracellular neurofibrillary tangles (NFTs) composed of hyper-phosphorylated microtubule-associated protein tau (MAP-tau), and microtubule destabilization. Early-onset autosomal dominant AD genes are associated with excessive Aβ accumulation, however cognitive impairment best correlates with NFTs and disrupted microtubules. The mechanisms linking Aβ and NFT pathologies in AD are unknown. Here, we propose that sequestration of zinc by Aβ-amyloid deposits (Aβ oligomers and plaques) not only drives Aβ aggregation, but also disrupts zinc homeostasis in zinc-enriched brain regions important for memory and vulnerable to AD pathology, resulting in intra-neuronal zinc levels, which are either too low, or excessively high. To evaluate this hypothesis, we 1) used molecular modeling of zinc binding to the microtubule component protein tubulin, identifying specific, high-affinity zinc binding sites that influence side-to-side tubulin interaction, the sensitive link in microtubule polymerization and stability. We also 2) performed kinetic modeling showing zinc distribution in extra-neuronal Aβ deposits can reduce intra-neuronal zinc binding to microtubules, destabilizing microtubules. Finally, we 3) used metallomic imaging mass spectrometry (MIMS) to show anatomically-localized and age-dependent zinc dyshomeostasis in specific brain regions of Tg2576 transgenic, mice, a model for AD. We found excess zinc in brain regions associated with memory processing and NFT pathology. Overall, we present a theoretical framework and support for a new theory of AD linking extra-neuronal Aβ amyloid to intra-neuronal NFTs and cognitive dysfunction. The connection, we propose, is based on β-amyloid-induced alterations in zinc ion concentration inside neurons affecting stability of polymerized microtubules, their binding to MAP-tau, and molecular dynamics involved in cognition. Further, our theory supports novel AD therapeutic strategies targeting intra-neuronal zinc homeostasis and microtubule dynamics to prevent neurodegeneration and cognitive decline

    Does the Dose of Standard Adjuvant Chemotherapy Affect the Triple-negative Breast Cancer Benefit from Extended Capecitabine Metronomic Therapy? An Exploratory Analysis of the SYSUCC-001 Trial

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    Ying Chen,1,2,* Wen-Xia Li,1,2,* Jia-Hua Wu,1,2 Geng-Hang Chen,2 Chun-Min Yang,1,2 Hai Lu,1,2 Xi Wang,3 Shu-Sen Wang,4 Heng Huang,5 Li Cai,6 Li Zhao,7 Rou-Jun Peng,8 Ying Lin,9 Jun Tang,3 Jian Zeng,10 Le-Hong Zhang,11 Yong-Li Ke,12 Xian-Ming Wang,13 Xin-Mei Liu,14 An-Qin Zhang,15 Fei Xu,4 Xi-Wen Bi,4 Jia-Jia Huang,4 Ji-Bin Li,16 Dan-Mei Pang,17 Cong Xue,4 Yan-Xia Shi,4 Zhen-Yu He,18 Huan-Xin Lin,18 Xin An,4 Wen Xia,4 Ye Cao,16 Ying Guo,16 Ruo-Xi Hong,4 Kui-Kui Jiang,4 Yong-Yi Zhong,4 Ge Zhang,19 Piyawan Tienchaiananda,20 Masahiro Oikawa,21 Zhong-Yu Yuan,4 Qian-Jun Chen22,23 1Department of Breast Surgery, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, People’s Republic of China; 2Department of Breast Surgery, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China; 3Department of Breast Oncology, Sun Yat-sen University Cancer Center, the State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 4Department of Medical Oncology, Sun Yat-sen University Cancer Center, the State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 5Department of Breast Oncology, Lianjiang People’s Hospital, Lianjiang, People’s Republic of China; 6Department of Medical Oncology, The Affiliated Tumour Hospital of Harbin Medical University, Harbin, People’s Republic of China; 7Department of Breast Oncology, Guangzhou First People Hospital, Guangzhou, People’s Republic of China; 8Department of Integrated Therapy in Oncology, Sun Yat-sen University Cancer Center, the State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 9Department of Breast Oncology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, People’s Republic of China; 10Department of Breast Oncology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, People’s Republic of China; 11Department of Breast Oncology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China; 12Department of Breast Oncology, General Hospital of PLA Guangzhou Military Area, Guangzhou, People’s Republic of China; 13Department of Breast Oncology, Shenzhen Second People’s Hospital, Shenzhen, People’s Republic of China; 14Department of Breast Oncology, Haikou People’s Hospital, Haikou, People’s Republic of China; 15Department of Breast Oncology, Maternal and Child Health Care Hospital of Guangdong Province, Guangzhou, People’s Republic of China; 16Department of Good Clinical Practice, Sun Yat-sen University Cancer Center, the State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 17Department of Medical Oncology, Foshan First People’s Hospital, Foshan, People’s Republic of China; 18Department of Radiotherapy, Sun Yat-sen University Cancer Center, the State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China; 19Law Sau Fai Institute for Advancing Translational Medicine in Bone and Joint Diseases (TMBJ), School of Chinese Medicine, Hong Kong Baptist University, Hong Kong; 20Division of Medical Oncology, Department of Medicine, Faculty of Medicine, Rangsit University, Rajavithi Hospital, Bangkok, Thailand; 21The Department of Breast Surgery, New-wa-kai Oikawa Hospital, Fukuoka, Japan; 22State Key Laboratory of Traditional Chinese Medicine Syndrome/Departments of Gynecologic Oncology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China; 23State Key Laboratory of Traditional Chinese Medicine Syndrome, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Qian-Jun Chen, 55N, Neihuanxi Road, Guangzhou, Guangdong, 510006, People’s Republic of China, Tel +86 1868883505, Email [email protected] Zhong-Yu Yuan, 651 Dongfeng Road, Guangzhou, Guangdong, 510060, People’s Republic of China, Tel +86 13798027658, Email [email protected]: Results from studies of extended capecitabine after the standard adjuvant chemotherapy in early stage triple-negative breast cancer (TNBC) were inconsistent, and only low-dose capecitabine from the SYSUCC-001 trial improved disease-free survival (DFS). Adjustment of the conventional adjuvant chemotherapy doses affect the prognosis and may affect the efficacy of subsequent treatments. This study investigated whether the survival benefit of the SYSUCC-001 trial was affected by dose adjustment of the standard adjuvant chemotherapy or not.Patients and Methods: We reviewed the adjuvant chemotherapy regimens before the extended capecitabine in the SYSUCC-001 trial. Patients were classified into “consistent” (standard acceptable dose) and “inconsistent” (doses lower than acceptable dose) dose based on the minimum acceptable dose range in the landmark clinical trials. Cox proportional hazards model was used to investigate the impact of dose on the survival outcomes.Results: All 434 patients in SYSUCC-001 trial were enrolled in this study. Most of patients administered the anthracycline-taxane regimen accounted for 88.94%. Among patients in the “inconsistent” dose, 60.8% and 47% received lower doses of anthracycline and taxane separately. In the observation group, the “inconsistent” dose of anthracycline and taxane did not affect DFS compared with the “consistent” dose. Moreover, in the capecitabine group, the “inconsistent” anthracycline dose did not affect DFS compared with the “consistent” dose. However, patients with “consistent” taxane doses benefited significantly from extended capecitabine (P=0.014). The sufficient dose of adjuvant taxane had a positive effect of extended capecitabine (hazard ratio [HR] 2.04; 95% confidence interval [CI] 1.02 to 4.06).Conclusion: This study found the dose reduction of adjuvant taxane might negatively impact the efficacy of capecitabine. Therefore, the reduction of anthracycline dose over paclitaxel should be given priority during conventional adjuvant chemotherapy, if patients need dose reduction and plan for extended capecitabine.Keywords: adjuvant chemotherapy, capecitabine, SYSUCC-001, triple-negative breast cancer, TNB
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