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1.
J Phys Chem A ; 127(8): 1866-1873, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802640

RESUMO

This paper reports a theoretical study of valence shell excitation in CCl4 by high-energy electron impact. Generalized oscillator strengths are calculated for the molecule at the equation-of-motion coupled-cluster singles and doubles level. To elucidate the influence of nuclear dynamics on electron excitation cross-sections, the effects of molecular vibration are included in the calculation. Based on a comparison with recent experimental data, several reassignments of spectral features are made, and it is found that excitations from the Cl 3p nonbonding orbitals to σ* antibonding orbitals, 7a1 and 8t2, play dominant roles below the excitation energy of ∼9 eV. Furthermore, the calculations reveal that distortion of the molecular structure due to the asymmetric stretching vibration significantly affects the valence excitations at small momentum transfers, where contributions from dipole transitions are dominant. It indicates that vibrational effects have a considerable influence on Cl formation in the photolysis of CCl4.

2.
Entropy (Basel) ; 25(3)2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36981343

RESUMO

Based on the classical dynamical entropy, the channel coding theorem is investigated. Attempts to extend the dynamical entropy to quantum systems have been made by several researchers In 1999, Kossakowski, Ohya and I introduced the quantum dynamical entropy (KOW entropy) for completely positive maps containing an automorphism describing the time evolution. Its formulation used transition expectations and lifting in the sense of Accardi and Ohya and was studied as a measure of the complexity of quantum mechanical systems. This KOW entropy allowed the extension of generalized AF (Alicki and Fannes) entropy and generalized AOW (Accardi, Ohya and Watanabe) entropy. In addition, the S-Mixing entropy and S-mixing mutual-entropy were formulated by Ohya in 1985. Compound states are an important tool for formulating mutual entropy, and the complexity was constructed by the generalized AOW entropy. In this paper, the complexity associated with the entangled compound states in the C* dynamical system based on the generalized AOW entropy based on the KOW entropy is investigated to lay the foundation for the proof of the theorem of channel coding for quantum systems. We show that the fundamental inequalities of the mutual entropy are satisfied when the initial state is transmitted over the channel changes with time.

3.
Scand J Gastroenterol ; 57(2): 165-168, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34663142

RESUMO

BACKGROUND AND AIM: Mayo endoscopic subscore is a simple and validated endoscopic score for ulcerative colitis but the range of inflammation was not considered for scoring. There were few reports analyzing the range of inflammation for clinical relapse using Mayo endoscopic subscore (MES). The aim of this study is to investigate the relapsing potential of limited mucosal inflammation on endoscopic remission equivalent to MES of 0. METHODS: For this retrospective observational study, ulcerative colitis patients underwent total colonoscopy were enrolled. Small mucosal lesion (SML) was defined as limited inflammation of range less than 3 cm. Clinical relapse was analyzed using the Kaplan-Meier curve with log-rank test, and factors associated with clinical relapse was analyzed using the cox proportional hazard regression model. RESULTS: A total of 102 periods with mucosal healing or modified MES of 0 with SML were analyzed. In 12-months observation periods, clinical relapse occurred more frequently in MES of 1 than in MES of 0 or modified MES of 0 with SML, but it was comparable between MES of 0 and modified MES of 0 with SML. When compared to patients with modified MES of 0 with SML, the hazard ratio in patients with MES of 1 (6.55; p = .028) was significantly high but similar in those with MES of 0 (2.59; p = .29). CONCLUSIONS: Small mucosal inflammation in UC does not affect the clinical relapse if most of the mucosa achieved a score similar to MES of 0.


Assuntos
Colite Ulcerativa , Colite Ulcerativa/patologia , Colonoscopia , Humanos , Inflamação/patologia , Mucosa Intestinal/patologia , Recidiva , Índice de Gravidade de Doença
4.
Tohoku J Exp Med ; 257(4): 301-308, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35598974

RESUMO

Leucine-rich alpha-2 glycoprotein (LRG) is a novel biomarker for monitoring disease activity in inflammatory bowel disease (IBD). The aim of this study was to evaluate its utility in monitoring disease activity. In this retrospective study based on case records between August 2020 and July 2021 at our two centers, we examined the correlation between serum levels of LRG and C-reactive protein (CRP) with disease activity in IBD patients. Background factors related to serum LRG levels were also analyzed. Overall, 47 Crohn's disease (CD) and 123 ulcerative colitis (UC) patients were evaluated. In patients with CD, LRG and CRP levels correlated with Harvey-Bradshaw Index (HBI) and Simple Endoscopic Score for CD (SES-CD) (LRG and HBI, r = 0.397; LRG and SES-CD, r = 0.637; CRP and HBI, r = 0.253; CRP and SES-CD, r = 0.332). In patients with UC, LRG and CRP significantly correlated with the partial Mayo score (PMS) and Mayo endoscopic subscore (MES) (LRG and PMS, r = 0.3; CRP and PMS, r = 0.282; LRG and MES, r = 0.424; CRP and MES, r = 0.459). In CD patients with normal CRP, serum LRG level was significantly higher in those with mucosal inflammation than in those with mucosal healing (16.4 vs. 10.7 µg/ mL). Stenosis was associated with serum LRG levels in CD group using multiple regression analysis. Therefore, LRG is a useful biomarker for monitoring disease activity and mucosal inflammation, and indicates the status of intestinal stenosis in IBD patients.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Biomarcadores , Proteína C-Reativa/metabolismo , Colite Ulcerativa/complicações , Constrição Patológica/complicações , Doença de Crohn/complicações , Glicoproteínas , Humanos , Inflamação/complicações , Doenças Inflamatórias Intestinais/complicações , Leucina , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
Tohoku J Exp Med ; 257(1): 65-71, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35387907

RESUMO

Disruption of cancer screening programs and diagnoses of gastrointestinal cancers by the COVID-19 pandemic has been reported; however, little attention has been paid to the situation in depopulated areas with low infection rates. Akita Prefecture is one of the most depopulated areas of Japan and has the lowest COVID-19 infection rate per capita; at the same time, the prefecture has been top-ranked for mortality due to gastrointestinal cancer for years. In this population-based study in Akita Prefecture, we investigated the occurrence of gastrointestinal cancers and the number of cancer screening procedures over the five-year period of 2016-2020, employing a database from the collaborative Akita Prefecture hospital-based registration system of cancers. The occurrence of gastrointestinal cancers, especially esophago-gastric cancers, declined by 11.0% in 2020, when the COVID-19 pandemic affected the overall healthcare system, compared with the average of 2016-2019. Nonetheless, the occurrence of advanced-stage (stage IV) esophago-gastric cancers increased by 7.2% in 2020. The decrease in the gastrointestinal cancer diagnosis rate in 2020 coincided with a 30% decline in the total number of regular population-based screening programs. Under the ongoing COVID-19 pandemic, cancer screening was uniformly suspended throughout Japan. Accordingly, the COVID-19 pandemic has substantially disrupted the cancer screening system, leading to delays in diagnoses of gastrointestinal cancer, even in depopulated areas (Akita Prefecture) of Japan with a low prevalence of infection. Suspension of cancer screening procedures during an infectious disease pandemic should be thoroughly considered for each region based on the cancer incidence and infection status in that area.


Assuntos
COVID-19 , Neoplasias Gastrointestinais , Neoplasias Gástricas , COVID-19/epidemiologia , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/epidemiologia , Humanos , Japão/epidemiologia , Pandemias
6.
Int Heart J ; 63(2): 278-285, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35296618

RESUMO

This study examined quality indicators (QIs) for heart failure (HF) in patients' referral documents (PRDs).We conducted a nationwide questionnaire survey to identify information that general practitioners (GPs) would like hospital cardiologists (HCs) to include in PRDs and that HCs actually include in PRDs. The percentage of GPs that desired each item included in PRDs was converted into a deviation score, and items with a deviation score of ≥ 50 were defined as QIs. We rated the quality of PRDs provided by HCs based on QI assessment.We received 281 responses from HCs and 145 responses from GPs. The following were identified as QIs: 1) HF cause; 2) B-type natriuretic peptide (BNP) or N-terminal pro-BNP concentration; 3) left ventricular ejection fraction or echocardiography; 4) body weight; 5) education of patients and their families on HF; 6) physical function, and 7) functions of daily living. Based on QI assessment, only 21.7% of HCs included all seven items in their PRDs. HCs specializing in HF and institutions with many full-time HCs were independently associated with including the seven items in PRDs.The quality of PRDs for HF varies among physicians and hospitals, and standardization is needed based on QI assessment.


Assuntos
Insuficiência Cardíaca , Indicadores de Qualidade em Assistência à Saúde , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Japão , Encaminhamento e Consulta , Volume Sistólico , Função Ventricular Esquerda
7.
Circ J ; 85(9): 1565-1574, 2021 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-34234052

RESUMO

BACKGROUND: The purpose of this study was to clarify the current status and issues of community collaboration in heart failure (HF) using a nationwide questionnaire survey.Methods and Results:We conducted a survey among hospital cardiologists and general practitioners (GPs) using a web-based questionnaire developed with the Delphi method, to assess the quality of community collaboration in HF. We received responses from 46 of the 47 prefectures in Japan, including from 281 hospital cardiologists and 145 GPs. The survey included the following characteristics and issues regarding community collaboration. (1) Hospital cardiologists prioritized medical intervention for preventing HF hospitalization and death whereas GPs prioritized supporting the daily living of patients and their families. (2) Hospital cardiologists have not provided information that meets the needs of GPs, and few regions have a community-based system that allows for the sharing of information about patients with HF. (3) In the transition to home care, there are few opportunities for direct communication between hospitals and community staff, and consultation systems are not well developed. CONCLUSIONS: The current study clarified the real-world status and issues of community collaboration for HF in Japan, especially the differences in priorities for HF management between hospital cardiologists and GPs. Our data will contribute to the future direction and promotion of community collaboration in HF management.


Assuntos
Cardiologistas , Clínicos Gerais , Insuficiência Cardíaca , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/terapia , Humanos , Japão , Encaminhamento e Consulta
8.
Heart Vessels ; 36(10): 1496-1505, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33825976

RESUMO

Chronic kidney disease is a prognostic factor for cardiovascular disease. Worsening renal function (WRF), specifically, is an important predictor of mortality in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention (PCI). We evaluate the prognostic impact of mid-term WRF after PCI on future cardiovascular events. We examined the renal function data of 1086 patients in the first year after PCI using the SHINANO 5-year registry. Patients were divided into two groups, mid-term WRF and non-mid-term WRF, and primary outcomes were major adverse cardiovascular events (MACE) and death. Mid-term WRF was defined as an increase in creatinine (≥ 0.3 mg/dL) in the first year after PCI. Mid-term WRF was found in 101 patients (9.3%), and compared to non-mid-term WRF, it significantly increased the incidence of MACE (p < 0.001), and all-cause death (p < 0.001), myocardial infarction (p = 0.001). Furthermore, mid-term WRF patients had higher incidence of future heart failure (p < 0.001) and new-onset atrial fibrillation (p = 0.01). Patients with both mid-term WRF and chronic kidney disease had increased MACE compared to patients with either condition alone (p < 0.001). Similarly, patients with mid-term WRF and acute kidney injury had increased MACE compared to patients with either condition alone (p < 0.001). Multivariate Cox regression analysis revealed mid-term WRF as a strong predictor of MACE (hazard ratio: 2.50, 95% confidence interval 1.57-3.98, p < 0.001). Mid-term WRF after PCI negatively affects MACE, as well as future admission due to heart failure and new-onset atrial fibrillation, chronic kidney disease, and acute kidney injury.


Assuntos
Injúria Renal Aguda , Intervenção Coronária Percutânea , Insuficiência Renal Crônica , Injúria Renal Aguda/epidemiologia , Fibrilação Atrial/epidemiologia , Insuficiência Cardíaca/epidemiologia , Humanos , Rim/fisiologia , Infarto do Miocárdio/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Sistema de Registros , Insuficiência Renal Crônica/epidemiologia
9.
Entropy (Basel) ; 23(3)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809816

RESUMO

This paper is our attempt, on the basis of physical theory, to bring more clarification on the question "What is life?" formulated in the well-known book of Schrödinger in 1944. According to Schrödinger, the main distinguishing feature of a biosystem's functioning is the ability to preserve its order structure or, in mathematical terms, to prevent increasing of entropy. However, Schrödinger's analysis shows that the classical theory is not able to adequately describe the order-stability in a biosystem. Schrödinger also appealed to the ambiguous notion of negative entropy. We apply quantum theory. As is well-known, behaviour of the quantum von Neumann entropy crucially differs from behaviour of classical entropy. We consider a complex biosystem S composed of many subsystems, say proteins, cells, or neural networks in the brain, that is, S=(Si). We study the following problem: whether the compound system S can maintain "global order" in the situation of an increase of local disorder and if S can preserve the low entropy while other Si increase their entropies (may be essentially). We show that the entropy of a system as a whole can be constant, while the entropies of its parts rising. For classical systems, this is impossible, because the entropy of S cannot be less than the entropy of its subsystem Si. And if a subsystems's entropy increases, then a system's entropy should also increase, by at least the same amount. However, within the quantum information theory, the answer is positive. The significant role is played by the entanglement of a subsystems' states. In the absence of entanglement, the increasing of local disorder implies an increasing disorder in the compound system S (as in the classical regime). In this note, we proceed within a quantum-like approach to mathematical modeling of information processing by biosystems-respecting the quantum laws need not be based on genuine quantum physical processes in biosystems. Recently, such modeling found numerous applications in molecular biology, genetics, evolution theory, cognition, psychology and decision making. The quantum-like model of order stability can be applied not only in biology, but also in social science and artificial intelligence.

10.
J Phys Chem A ; 124(49): 10258-10265, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33258373

RESUMO

This paper investigates vibrational excitation effects on valence electron momentum distributions of dimethyl ether. A symmetric noncoplanar (e, 2e) experiment has been performed for the molecule at a high temperature (980 K) as well as at room temperature (300 K). For comparison, theoretical calculations with vibrational effects being involved have also been carried out. Changes of the momentum profiles with the rise of temperature are observed for the 2b1 and 6a1 orbitals, indicating that distortion of these molecular orbitals is appreciably enhanced upon excitation of the methyl torsional vibrations. The present study provides a way for exploring the influence of vibrational excitation on electronic wavefunctions of molecules.

11.
Digestion ; 101(1): 31-37, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31722351

RESUMO

BACKGROUND: Gastrointestinal bleeding (GIB) is one of the most common medical emergencies. We investigated the overall mortality after GIB in our institute and analyzed the prognostic factors in upper GIB (UGIB) and lower GIB (LGIB) separately. SUMMARY: Between January 2010 and December 2018, 190 patients diagnosed with GIB in our hospital were retrospectively enrolled. Clinical records and biological data were collected. Risks for rebleeding and in-hospital mortality were assessed by a logistic regression analysis. Overall, the rebleeding rate and in-hospital mortality were 22.6 and 7.6%, respectively. GIB itself was not the direct cause of death in any cases. While older age (>65 years) was a significant risk factor for rebleeding in UGIB with an OR of 6.1 and 95% CI of 1.3-29.1, a poorer performance status (PS; ≥3) was a strong risk factor for rebleeding in LGIB, with an OR of 11.8 and 95% CI of 1.7-83.8. Poor PS and tachycardia (>100/min) were significantly associated with mortality in both UGIB and LGIB. In contrast, hypoalbuminemia (<3.0 g/dL) was associated with the mortality in LGIB alone. Key Messages: There were considerable differences in the risk factors for rebleeding and in-hospital mortality between UGIB and LGIB. The overall in-hospital mortality was 7.9% after GIB, including that a substantial portion of patients with GIB died from systemic complications after successful endoscopic hemostasis. Physicians need to diligently perform systematic treatment for GIB, which may be particularly important in societies of advancing aging, like Japan.


Assuntos
Hemorragia Gastrointestinal/mortalidade , Hemorragia Gastrointestinal/terapia , Hemostase Endoscópica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Mortalidade Hospitalar , Humanos , Japão , Trato Gastrointestinal Inferior , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiologia Intervencionista , Recidiva , Estudos Retrospectivos , Fatores de Risco , Trato Gastrointestinal Superior
12.
Antonie Van Leeuwenhoek ; 113(1): 71-81, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31414275

RESUMO

Aquatic pathogen Aeromonas hydrophila produces an array of virulence factors, many of which are excreted proteins that causes infectious disease in fish, reptiles, and humans. Aerolysin, a haemolytic toxin, is the most well-known of the A. hydrophila virulence factors and is encoded by aerA. Although used as a virulence gene marker in several studies, recent whole-genome sequencing data suggest there may be some variation in aerolysin genes, as well as in the genetic environment of these genes, among A. hydrophila strains. Here, we used PCR-based assays to examine gene arrangement in the traditional aerA region of 42 aerA-minus clinical and environmental A. hydrophila isolates. PCR primers were designed based on known genes from within the target regions of reference strains carrying non-aerA aerolysin genes. Analyses revealed four different gene arrangement patterns among the isolates, indicating considerable genetic diversity in the target region. While 19 of the 21 environmental isolates showed the same gene pattern, all four patterns were represented among the clinical isolates, implying that the gene pattern is highly conserved in the target region among environmental isolates. Further analysis of the gene regions showed that the predominant pattern among environmental isolates, which did not contain an aerolysin gene, appeared to be the progenitor of the other three patterns, which likely arose as a result of gene acquisition, deletion, and rearrangement events during the evolution of A. hydrophila, and may be linked to the acquisition of aerolysin genes. These findings shed light on the evolution of virulence in A. hydrophila.


Assuntos
Aeromonas hydrophila/genética , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Reação em Cadeia da Polimerase
13.
J Chem Phys ; 152(16): 164301, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32357771

RESUMO

We experimentally investigate the molecular-orientation dependence of high-energy electron-impact ionization of CO. The direction of the molecular-axis with respect to the momentum transfer vector K is deduced from the angular correlation between the fragment ion and the scattered electron. The experimental results on the 3 2Π ionization reveal that at small momentum transfer, the ionization probability near the threshold is higher when K points toward the C atom along the molecular axis than when it is in the opposite direction. Such a forward-backward asymmetry does not appear in single-photon ionization and requires non-dipole contributions. It is also shown that the {4 2Σ+ + 5 2Σ+ + 6 2Σ+} ionization preferentially takes place in the vicinity of the molecular orientation parallel to K at small momentum transfer, while non-dipole contributions cause the decrease in the relative intensity of the parallel direction.

14.
Entropy (Basel) ; 22(3)2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33286072

RESUMO

It has been shown that joint probability distributions of quantum systems generally do not exist, and the key to solving this concern is the compound state invented by Ohya. The Ohya compound state constructed by the Schatten decomposition (i.e., one-dimensional orthogonal projection) of the input state shows the correlation between the states of the input and output systems. In 1983, Ohya formulated the quantum mutual entropy by applying this compound state. Since this mutual entropy satisfies the fundamental inequality, one may say that it represents the amount of information correctly transmitted from the input system through the channel to the output system, and it may play an important role in discussing the efficiency of information transfer in quantum systems. Since the Ohya compound state is separable state, it is important that we must look more carefully into the entangled compound state. This paper is intended as an investigation of the construction of the entangled compound state, and the hybrid entangled compound state is introduced. The purpose of this paper is to consider the validity of the compound states constructing the quantum mutual entropy type complexity. It seems reasonable to suppose that the quantum mutual entropy type complexity defined by using the entangled compound state is not useful to discuss the efficiency of information transmission from the initial system to the final system.

15.
J Clin Gastroenterol ; 53(4): e164-e170, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29498952

RESUMO

GOALS: To investigate retrospectively the risk factors for synchronous and metachronous cancers in the upper gastrointestinal tract in patients with superficial esophageal squamous cell carcinoma (ESCC). BACKGROUND: In patients who have received endoscopic resection (ER) for ESCC, synchronous and metachronous cancers are frequently detected not only in the esophagus but also in the head and neck area and the stomach. STUDY: A total of 285 patients who received ER for superficial ESCC were enrolled in this analysis. These patients were periodically followed-up endoscopically. Cumulative occurrence rates of the metachronous second primary cancers were determined by Kaplan-Meier method. Risk factors for synchronous and metachronous cancers in the head and neck area and the stomach were determined by logistic regression analyses. RESULTS: During a mean follow-up period of 76 months, the 5-year cumulative occurrence of metachronous esophageal, head and neck, and stomach cancer was 14.0%, 2.8%, and 4.1%, respectively. Although the presence of multiple lugol-voiding lesions in the esophagus was a significant risk factor for synchronous and metachronous head and neck cancers (odds ratio, 3.8; 95% confidence interval, 1.7-9.0), older age (>65 y) was a significant risk factor for synchronous and metachronous gastric cancer (odds ratio, 3.1; 95% confidence interval, 1.2-9.3). CONCLUSIONS: The risk factors for the cooccurrence of head and neck cancer and that of gastric cancer in patients with ESCC differ. This information will likely be useful for managing patients who have been treated with ER for ESCC and who possess carcinogenic potential throughout the upper gastrointestinal tract.


Assuntos
Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Neoplasias Gástricas/epidemiologia , Idoso , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/epidemiologia , Neoplasias Primárias Múltiplas/patologia , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/patologia , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/patologia
16.
J Chem Phys ; 150(19): 194306, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117792

RESUMO

We report an electron momentum spectroscopy study on methyl formate. A symmetric noncoplanar (e, 2e) experiment has been performed at an incident electron energy of 1.2 keV and electron momentum profiles of the valence orbitals have been obtained. On the basis of the result, assignments of the 10a'-1 and 1a″-1 bands have been made to resolve a contradiction between photoelectron spectroscopy and Penning ionization electron spectroscopy studies. Comparisons between experiment and theory reveal that the influence of the molecular vibration has to be taken into account for a proper understanding of the electron momentum profiles. Contributions of individual vibrational normal modes have also been investigated in detail by means of the harmonic analytical quantum mechanical approach.

17.
Phys Chem Chem Phys ; 20(2): 1063-1071, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29236114

RESUMO

We report an (e, e+ion) spectroscopy study on electron-induced dissociative ionization of N2. Vector correlation between the scattered electron and N+ ion has been measured for inner-valence ionization of N2 at an incident electron energy of 1.4 keV and scattering angles of 2.2°, 4.2°, and 8.2°. By analyzing the experimental data, partial ion yield spectra have been obtained for transitions to the C 2Σ, F 2Σ, and 2σ ion states, showing that the individual transitions depend on the momentum transferred to the target, K, in different ways. The molecular-orientation dependence of the ionization cross section has subsequently been examined for the F 2Σ ionization. To account for the angular anisotropy of the scattering cross section, a compact analytical form has been developed. It is elucidated that for small K the F 2Σ ionization preferentially takes place when the molecule has its axis aligned parallel to the momentum transfer vector due to σu shape resonance, while the angular distribution drastically changes with K, indicating strong influences of non-dipole interaction on the ionization dynamics. It has been shown that the present method provides a powerful means to explore K-dependent stereodynamics in electron-induced dissociative ionization of molecules.

18.
Tohoku J Exp Med ; 246(2): 131-140, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30369514

RESUMO

With the decreasing global trend in the Helicobacter pylori infection rate, compositional changes in the gastric cancer subsites have occurred worldwide. However, the compositional changes in Asian countries, including Japan, remain to be clarified. The aim of this study is to investigate the latest chronological changes in the gastric cancer subsite using a hospital-based registration system in Akita prefecture in Japan. From 2007-2015, subsites of gastric cancers were coded according to the International Classification of Diseases for Oncology (ICD-03). The nine-year registration period was divided into the three 3-year periods: 2007-2009, 2010-2012, and 2013-2015. A total of 10,804 cases of gastric cancer were registered. The proportion of cardiac cancer among total gastric cancer slightly but significantly declined from 12.1% in 2007-2009 to 9.2% in 2013-2015 (P < 0.01). Among non-cardia cancer, the proportion of corpus cancer significantly increased from 41.3% to 50.2% during the study period (P < 0.01), while that of antropylorus cancer significantly decreased from 37.6% to 34.3% (P < 0.05). Such compositional changes in the gastric cancer subsite were observed largely in men, regardless of the histologic subtype of cancer. With the decreasing H. pylori infection rate, compositional changes in the gastric cancer subsite are occurring in Japan. While the proportion of cardia and antropylorus cancer is declining, that of corpus cancer is increasing, indicating diverse etiology of gastric carcinogenesis depending on the subsites. Identifying the most common sites of occurrence, may help to improve the efficiency of screening for gastric cancer.


Assuntos
Hospitais , Sistema de Registros , Neoplasias Gástricas/patologia , Idoso , Feminino , Humanos , Japão , Masculino , Fatores de Tempo
19.
Philos Trans A Math Phys Eng Sci ; 375(2106)2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-28971948

RESUMO

Transmitted complexity (mutual entropy) is one of the important measures for quantum information theory developed recently in several ways. We will review the fundamental concepts of the Kossakowski, Ohya and Watanabe entropy and define a transmitted complexity for quantum dynamical systems.This article is part of the themed issue 'Second quantum revolution: foundational questions'.

20.
J Phys Chem A ; 121(1): 277-287, 2017 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27998060

RESUMO

The interpretation of experimental electron momentum distributions (EMDs) of ethanol, one of the simplest molecules having conformers, has confused researchers for years. High-level calculations of Dyson orbital EMDs by thermally averaging the gauche and trans conformers as well as molecular dynamical simulations failed to quantitatively reproduce the experiments for some of the outer valence orbitals. In this work, the valence shell electron binding energy spectrum and EMDs of ethanol are revisited by the high-sensitivity electron momentum spectrometer employing symmetric noncoplanar geometry at an incident energy of 1200 eV plus binding energy, together with a detailed analysis of the influence of vibrational motions on the EMDs for the two conformers employing a harmonic analytical quantum mechanical (HAQM) approach by taking into account all of the vibrational modes. The significant discrepancies between theories and experiments in previous works have now been interpreted quantitatively, indicating that the vibrational effect plays a significant role in reproducing the experimental results, not only through the low-frequency OH and CH3 torsion modes but also through other high-frequency ones. Rational explanation of experimental momentum profiles provides solid evidence that the trans conformer is slightly more stable than the gauche conformer, in accordance with thermodynamic predictions and other experiments. The case of ethanol demonstrates the significance of considering vibrational effects when performing a conformational study on flexible molecules using electron momentum spectroscopy.

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