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1.
Surface crossing of the potential energy surfaces (PESs) and the formulation of differentiable PES functions are discussed in the quartet N+ 2 + O2 system containing the T shape intermediate complex. Consideration of the ion-dipole interaction between N2 and O2 fragments due to the induced dipole moment of the neutral molecule gives a good image of the surface crossing between the quartet reactant state (N+ 2 ···O2) and the quartet product state (N2 ···O+ 2) for the charge transfer (CT) reaction in terms of the conventional harpooning mechanism. Differentiable functions of PESs are constructed for the reactant and product states that may be applied for 3-dimensional dynamics calculations by means of wavepackets, and examples of 2-dimensional wavepacket dynamics calculations are introduced. Further, electron transfer processes and local electronic nature in the CT reaction are discussed in terms of the quantum mechanical energy densities based on regional density functional theory. Regional partitioning by using the kinetic energy density provides a new concept of electron transfer, and the tension density provides new images of microscopic electronic stresses.  相似文献   
2.
位置灵敏型光电倍增管(PS-PMT)代表了基于单个管子的原理开发新概念γ相机的技术进步.最近,日本滨松公司出品了一种新型紧凑型的PSPMT—R7600-C12.根据正电子放射断层成像系统(PET)的应用特点,我们测试了由该PS-PMT组合成的闪烁晶体阵列探测器的空间分辨率、空间线性度、增益均匀性及时间分辨率LSO与该PS-PMT的组合空间分辨率达到1.4mm,而且显示出良好的空间线性、增益均匀性及优异的时间分辨特性.  相似文献   
3.
Objective: The study aimed to demonstrate the significance of early postoperative physical therapy interventions on clinical outcomes by determining the influence of the distance walked under the supervision of a physical therapist in the early postoperative period after liver cancer. Methods: All consecutive patients who underwent surgery for liver cancer between April 2018 and March 2020 were eligible for enrollment in the study. The total walking distance during physical therapy till the third postoperative day was examined. The clinical outcomes comprised duration of postoperative hospital stay, time to independent walking, and occurrence of postoperative complications. For data analysis, the patients were divided into two groups: those who walked more than the median total distance (the long-distance group) and those who walked less than the median distance (the short-distance group). We used propensity score matching to match the background characteristics between the groups. Results: Of the 65 patients who were eligible, 14 patients were included in the two groups each, after matching. The long-distance walking group had a significantly shorter hospital stay (9.0 days vs. 11.0 days, p=0.008) and a shorter time to independent walking (3.5 days vs. 7.5 days, p=0.019) than the short-distance walking group. There were no significant differences in postoperative complications between the two groups (7.1% vs. 42.8%, p=0.08). Conclusion: In the early postoperative period after liver cancer surgery, increasing the walking distance under the supervision of a physical therapist is important for improving clinical outcomes. Further prospective studies are needed to confirm the findings of this study.  相似文献   
4.
Abstract— By using a highly sensitive streak-camera technique, we investigate incorporation processes of HpD into malignant tumor m-KSA cells in vitro. The picosecond decays of the total fluorescence spectra, the wavelength-resolved fluorescence decays and the time-resolved fluorescence spectra from HpD in the cells are measured as a function of the incubation time. The results show that the aggregate component of HpD which has a fast fluorescence lifetime of 100 ps and a red-shifted band of ∼ 660 nm selectively accumulates more and more in the cells with the increase of the incubation time.  相似文献   
5.
Low lying electronic states of GdO have been investigated by complete active space SCF (CASSCF) and multireference singly and doubly excited configuration interaction (MRSDCI) calculations using the model core potential (MCP) method. The 4f electrons of Gd were included explicitly in the valence space. Relativistic effects were incorporated in the MCP and basis sets for Gd at the level of Cowan and Griffin's quasirelativistic Hartree—Fock method. The 9Σ? state (f7σ) was the ground state, and excited states, 9Δ, 9Π, 29Σ?, 7Σ?, 7Δ, 7Π, and 27E?, lay between 0 ~ 22 300 cm?1. The energy separations for these states agreed well with available experimental values. Calculated GdO bond lengths and vibrational frequencies for these states are in the ranges of 1.81–1.85 Å and of 800–880 cm?1, respectively. Mulliken population analysis showed that the gross population of the 4f orbitals was 7.1 e for all these states, and that the 4f electrons were strongly localized on Gd atom. The effective charge distribution was approximated to be Gd+O?. The σ and π bonding orbitals were mainly formed by Gd 5d and O 2p orbitals.  相似文献   
6.
SHR22000是日本滨松光子学株式会社开发的人体全身用正电子发射断层扫描仪. 扫描仪具有32层探测器环, 二维采集可形成63个切片, 病人孔径为60cm, 单个体位数据采集时间为3—5min.扫描仪的轴向视野为22.5cm, 经5个体位可以完成全身扫描, 视野中轴10mm处平均横向分辨率可达到3.2mm. 本文依照国际标准IEC 61675-1(亦即GB/T18988.1-2003)规定的各项指标对该扫描仪的空间分辨率、灵敏度、散射和计数率特性以及复原系数进行了测试, 并给出结果数据.  相似文献   
7.
We measure the femtosecond time-dependent, third-order nonlinear optical response for 4-(N, N-diethylamino)-β-nitrostyrene (DEANST) dissolved in N, N-dimethylformamide (DMF) from 0.1 to 1.4 M concentrations in the nonresonant region using time-resolved degenerate four-wave mixing (DFWM) spectroscopy. It is found that the DFWM signal profile with delayed responses depends on the concentration. This concentration dependence is determined to be mainly due to the group-velocity dispersion effect of the DEANST solution at the high concentration and the nonlinear response of the DMF solvent at the low concentration, but not due to the change in third-order nonlinear response of DEANST itself.  相似文献   
8.
Objectives: Patients with cancer cachexia have poor adherence to treatment, which affects their prognosis. Currently, there are many studies on the effects of rehabilitation on cancer cachexia, but there is a lack of evidence on the effects of nutrition therapy alone or in combination with rehabilitation and nutrition therapy. This article describes a case in which rehabilitation nutrition care process was effective in a patient with lung cancer who developed cancer cachexia. Methods: A 68-year-old woman was hospitalized for treatment of lung adenocarcinoma. The patient had moderate malnutrition, sarcopenia, and cachexia at the time of admission, so the authors intervened according to rehabilitation nutrition care process. The physiotherapist mainly prescribed resistance training and aerobic exercise, 40-60 minutes a day, 5-6 days a week. And the dietitian provided oral nutritional supplements (100 kcal, branched-chain amino acid: 3.0 g) in addition to hospital food and adjusted the patient''s energy intake to 26.96-33.05 kcal/kg/day and protein intake to 1.07-1.14 g/kg/day. Outcomes: Comparing the initial evaluation with the discharge, nutritional status, such as body mass index and skeletal muscle mass, and physical functions, such as maximum grip strength, gait speed, and functional independence measure (motor items), were improved. Conclusions: Rehabilitation nutrition care process-based interventions may improve nutritional status and physical functions more than exercise therapy alone in patients with lung cancer cachexia.  相似文献   
9.
Objective: Early mobilization and rehabilitation has become common and expectations for physical therapists working in intensive care units have increased in Japan. The objective of this study was to establish consensus-based minimum clinical practice standards for physical therapists working in intensive care units in Japan. It also aimed to make an international comparison of minimum clinical practice standards in this area. Methods: In total, 54 experienced physical therapists gave informed consent and participated in this study. A modified Delphi method with questionnaires was used over three rounds. Participants rated 272 items as “essential/unknown/non-essential”. Consensus was considered to be reached on items that over 70% of physical therapists rated as “essential” to clinical practice in the intensive care unit. Results: Of the 272 items in the first round, 188 were deemed essential. In round 2, 11 of the 62 items that failed to reach consensus in round 1 were additionally deemed essential. No item was added to the “essential” consensus in round 3. In total, 199 items were therefore deemed essential as a minimum standard of clinical practice. Participants agreed that 42 items were not essential and failed to reach agreement on 31 others. Identified 199 items were different from those in the UK and Australia due to national laws, cultural and historical backgrounds. Conclusions: This is the first study to develop a consensus-based minimum clinical practice standard for physical therapists working in intensive care units in Japan.  相似文献   
10.
An investigation has been made of the elementary surface reactions of alane and its surface dissociation products using density functional theory and a cluster model to elucidate the reaction mechanism of the deposition of aluminium in aluminium chemical vapour deposition (Al-CVD) using dimethylethylamine alane (DMEAA). Molecular structures, potential energies, and normal mode frequencies of the reactants, the products, and the transition states were calculated for each of the surface elementary reactions. Based on transition state theory, rate constants were estimated from the calculation results. The proposed reaction mechanism is the following. DMEAA is adsorbed onto an aluminium surface without any dissociation in the gas phase; DMEAA dissociates into dimethylethylamine (DMEA) and alane on the surface; DMEA is desorbed and alane remains adsorbed; the adsorbed alane molecules dissociate to AlH2, AlH, and H on the surface; hydrogen molecules to be desorbed are produced from the hydrogen atoms of AlH whose aluminium atoms form a quasi-aluminium surface on the original surface. The cluster size and structure dependence in quantum chemical calculations has also been considered using model clusters.  相似文献   
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