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BACKGROUND: Exposure to workplace aggression adversely affects workers' health; however, little is known regarding the impact of specific types of verbal content. AIMS: We aimed to examine the relationship between exposure to several types of aggressive words at work and the victim's depressive symptoms and sleep disturbance using text mining. METHODS: We conducted a longitudinal survey with 800 workers in wholesale and retail companies; of which, 500 responded to the follow-up survey. The Centre for Epidemiologic Studies-Depression Scale and Pittsburgh Sleep Quality Index were filled out by the participants, and their responses were analysed by logistic regression to evaluate the risk of depression or sleep problems. We collected exact aggressive words encountered at work over the past year as a dependent variable and classified it into four types using text mining, such as words criticizing one's performance. RESULTS: The follow-up rate was 63%. Exposure to words threatening one's life showed a significant relationship with the risk of depression (odds ratio [OR]â =â 13.94, 95% confidence interval [CI]â =â 1.76-110.56). The exposure to words criticizing one's job performance is significantly related to the risk of sleep disturbance (ORâ =â 5.56, 95% CIâ =â 2.08-14.88). CONCLUSIONS: These findings suggest that different contents of verbal aggression can have different impacts on workers' health. This indicates that not only overtly threatening and abusive language but also words related to one's performance can be a risk factor for workers, depending on how they are delivered. To mitigate the adverse effects, promoting effective communication and cultivating psychological detachment from work may be beneficial.
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Saúde Mental , Transtornos do Sono-Vigília , Humanos , Agressão , Local de Trabalho , Inquéritos e Questionários , Mineração de DadosRESUMO
Subtotal or total glossectomy for advanced tongue cancer has an adverse impact on swallowing. The purpose of this retrospective study was to analyse postoperative swallowing outcomes and to determine the ideal reconstruction method in these patients. The clinical and swallowing data of patients with tongue cancer who underwent subtotal glossectomy at the study institution between 2005 and 2019 were reviewed retrospectively. Data were available for 101 patients. The most common reconstruction method was a free rectus abdominis musculocutaneous flap (69 cases). The postoperative feeding tube dependency rate was 11.1% at discharge and 9.4% at 1 year. During the study period, laryngeal suspension and/or a cricopharyngeal myotomy was performed in 39 patients (38.6%), with 25 of these operations performed after 2017. Patients treated in 2017-2019 were significantly more able to take thin liquid (P < 0.001) and lost less weight (P = 0.015) compared to those treated in 2005-2016. Multivariate analysis of 61 patients who did not undergo laryngeal suspension and/or cricopharyngeal myotomy showed significant feeding tube dependency in those aged 65 years and older (P = 0.004). Thin liquid intake was significantly improved after subtotal glossectomy with laryngeal suspension, which led to better postoperative swallowing and improved quality of life.
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Retalho Miocutâneo , Neoplasias da Língua , Humanos , Glossectomia/métodos , Deglutição , Neoplasias da Língua/cirurgia , Estudos Retrospectivos , Qualidade de VidaRESUMO
Bisphosphonate (BPN) therapy, which mainly targets osteoporosis, evolves rapidly, leaving patients and physicians with a substantial collection of BPN regimen options. In this study, we aimed to clarify BPN medication adherence between weekly and monthly regimens using a nationwide claims database in Japan. We analyzed 5,016 patients with a screening period of 3 months and a 12 month observation period who started using BPN. We used propensity score matching with baseline patient background after dividing the patients into two groups: weekly and monthly BPN users. Medication adherence was calculated using proportion days cover (PDC). A PDC of > 80% was 55.9% and 52.5% in monthly and weekly formulas, respectively, during the 12 months after initiating BPN treatment. PDC-based BPN medication adherence was higher in monthly regimens than in weekly regimens (66.3±34.0 vs. 64.1±36.8%). No differences were found in the proportion of patients with > 80% medication adherence between the monthly and weekly regimens after stratifying patient background using propensity score matching. Our clinical findings highlight the importance of closely monitoring BPN medication adherence, particularly during the initial year of therapy. Notably, half of the patients with osteoporosis exhibited low medication adherence. Therefore, prioritizing monthly regimens over weekly regimens is crucial to promote BPN adherence and ensure optimal treatment outcomes.
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Conservadores da Densidade Óssea , Osteoporose , Humanos , Difosfonatos , Esquema de Medicação , Osteoporose/tratamento farmacológico , Adesão à Medicação , Resultado do Tratamento , Conservadores da Densidade Óssea/uso terapêuticoRESUMO
The superconducting (SC) phase diagram in uranium ditelluride is explored under magnetic fields (H) along the hard magnetic b axis using a high-quality single crystal with T_{c}=2.1 K. Simultaneous electrical resistivity and ac magnetic susceptibility measurements discern low- and high-field SC (LFSC and HFSC, respectively) phases with contrasting field-angular dependence. Crystal quality increases the upper critical field of the LFSC phase, but the H^{*} of â¼15 T, at which the HFSC phase appears, is always the same through the various crystals. A phase boundary signature is also observed inside the LFSC phase near H^{*}, indicating an intermediate SC phase characterized by small flux pinning forces.
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BACKGROUND: Recent studies have indicated the potential benefit of intraoperative near-infrared fluorescence imaging (NIR-FI) with indocyanine green in reducing early anastomotic leakage in colorectal surgery. Nonetheless, whether NIR-FI is effective in reducing structural sequelae of anastomotic leakage (SSAL) remains unclear. The aim of the present study was to investigate the impact of NIR-FI on SSAL after laparoscopic intersphincteric resection (ISR) of malignant rectal tumors. METHODS: This study was a retrospective single-center cohort study. A total of 293 consecutive patients who underwent elective laparoscopic ISR from May 2010 to August 2017 were included. Patients were divided into 2 groups; those who underwent elective laparoscopic ISR with lymphadenectomy for malignant rectal tumors using NIR-F (NIR-FI group) and those who underwent elective laparoscopic ISR with lymphadenectomy for malignant rectal tumors without using NIR-FI (control group). Thirty were excluded from the analyses (13 died, 7 had pelvic recurrence, and 10 were lost to follow-up). The primary endpoint was the rate of SSAL within 2 years after the primary resection, whereas the secondary endpoint was the rate of natural defecation via the anus at 2 years after the primary resection. Using various statistical analyses, such as propensity score matching, the rate of SSAL was compared between groups. RESULTS: A total of 263 patients were analyzed [177 males and 86 females, median age 61 (27-84) years]. Prior to propensity score matching (n = 263), NIR-FI was performed in 70 patients (26.6%) The rates of SSAL were 1.4% (1/70) in the NIR-FI group and 10.4% (20/193) in the control group (p = 0.02). After propensity score matching (n = 163), the rates of SSAL were 1.5% (1/66) in the NIR-FI group and 11.7% (12/103) in the control group (p = 0.02). Propensity score analyses, as well as simple regression analyses, revealed that NIR-FI was associated with a significantly lower risk of SSAL (OR 0.10-0.13; p = 0.03-0.05). CONCLUSIONS: NIR-FI is useful in reducing the rate of SSAL after laparoscopic ISR.
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Laparoscopia , Neoplasias Retais , Canal Anal/diagnóstico por imagem , Canal Anal/patologia , Canal Anal/cirurgia , Anastomose Cirúrgica , Fístula Anastomótica/diagnóstico por imagem , Fístula Anastomótica/etiologia , Fístula Anastomótica/prevenção & controle , Estudos de Coortes , Feminino , Humanos , Verde de Indocianina , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Imagem Óptica , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND: Placing a transanal endoscopic rectal purse-string suture (taEPS) is the crucial first component of transanal total mesorectal excision (taTME). However, no structured training is available to improve the procedure-specific skills for taEPS. The aim of this study was to create a performance rubric to improve taEPS skills and provide preliminary evidence for its validity. METHODS: A performance rubric was created based on technical considerations for taEPS, identified by consulting with taTME surgical and performance assessment experts. Ten independent, blinded raters assessed 10 videotaped taEPS procedures of consecutive taTME cases, at National Cancer Center Hospital East (NCCHE), Chiba, Japan, in January 2018-March 2019 using the rubric and the Global Operative Assessment of Laparoscopic Skills (GOALS). Internal consistency and inter-rater reliabilities were calculated. Videotaped taEPS procedures were timed and assessed by the rubric. Correlation between rubric scores and suturing times were analyzed. RESULTS: The rubric consists of four items: loading the needle (LN), atraumatic needle passage (AP), planned suture path (PS), and overall performance (OA). Videotaped performances were graded on a 3-point Likert scale; scores were calculated as sums of the points. Cronbach's α for internal consistency was 0.713. Inter-rater reliabilities were LN: 0.73, AP: 0.76, PS: 0.71, and OA: 0.70. Rubric and GOALS scores were strongly correlated (r = 0.964, p < 0.001). In 112 consecutive taEPS performances, rubric scores were strongly correlated with suturing time (r = - 0.69, p < 0.001). Surgeons' experience with taTME was associated with rubric scores and suturing time. CONCLUSIONS: This study provides preliminary validation for the taEPS skill performance rubric. The rubric's structured training may facilitate skill acquisition by providing trainees with critical clinical considerations.
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Laparoscopia , Protectomia , Neoplasias Retais , Cirurgia Endoscópica Transanal , Humanos , Laparoscopia/métodos , Complicações Pós-Operatórias/cirurgia , Neoplasias Retais/cirurgia , Reto/cirurgia , Suturas , Cirurgia Endoscópica Transanal/métodosRESUMO
Interleukin-27 (IL-27) is an immunoregulatory cytokine whose essential function is to limit immune responses. We found that the gene encoding cholesterol 25-hydroxylase (Ch25h) was induced in CD4+ T cells by IL-27, enhanced by transforming growth factorß (TGF-ß), and antagonized by T-bet. Ch25h catalyzes cholesterol to generate 25-hydroxycholesterol (25OHC), which was subsequently released to the cellular milieu, functioning as a modulator of T cell response. Extracellular 25OHC suppressed cholesterol biosynthesis in T cells, inhibited cell growth, and induced nutrient deprivation cell death without releasing high-mobility group box 1 (HMGB1). This growth inhibitory effect was specific to actively proliferating cells with high cholesterol demand and was reversed when extracellular cholesterol was replenished. Ch25h-expressing CD4+ T cells that received IL-27 and TGF-ß signals became refractory to 25OHC-mediated growth inhibition in vitro. Nonetheless, IL-27treated T cells negatively affected viability of bystander cells in a paracrine manner, but only if the bystander cells were in the early phases of activation. In mouse models of skin inflammation due to autoreactive T cells or chemically induced hypersensitivity, genetic deletion of Ch25h or Il27ra led to worse outcomes. Thus, Ch25h is an immunoregulatory metabolic switch induced by IL-27 and dampens excess bystander T effector expansion in tissues through its metabolite derivative, 25OHC. This study reveals regulation of cholesterol metabolism as a modality for controlling tissue inflammation and thus represents a mechanism underlying T cell immunoregulatory functions.
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Linfócitos T CD4-Positivos/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Interleucina-27/metabolismo , Pele/metabolismo , Esteroide Hidroxilases/metabolismo , Animais , Colesterol/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Esteroide Hidroxilases/genéticaRESUMO
Metal-organic frameworks (MOFs), which are self-assemblies of metal ions and organic ligands, provide a tunable platform to search a new state of matter. A two-dimensional (2D) perfect kagome lattice, whose geometrical frustration is a key to realizing quantum spin liquids, has been formed in the π - d conjugated 2D MOF [Cu3(C6S6)] n (Cu-BHT). The recent discovery of its superconductivity with a critical temperature T c of 0.25 kelvin raises fundamental questions about the nature of electron pairing. Here, we show that Cu-BHT is a strongly correlated unconventional superconductor with extremely low superfluid density. A nonexponential temperature dependence of superfluid density is observed, indicating the possible presence of superconducting gap nodes. The magnitude of superfluid density is much smaller than those in conventional superconductors and follows the Uemura's relation of strongly correlated superconductors. These results imply that the unconventional superconductivity in Cu-BHT originates from electron correlations related to spin fluctuations of kagome lattice.
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BACKGROUND: Geant4 is a Monte Carlo code extensively used in medical physics for a wide range of applications, such as dosimetry, micro- and nanodosimetry, imaging, radiation protection, and nuclear medicine. Geant4 is continuously evolving, so it is crucial to have a system that benchmarks this Monte Carlo code for medical physics against reference data and to perform regression testing. AIMS: To respond to these needs, we developed G4-Med, a benchmarking and regression testing system of Geant4 for medical physics. MATERIALS AND METHODS: G4-Med currently includes 18 tests. They range from the benchmarking of fundamental physics quantities to the testing of Monte Carlo simulation setups typical of medical physics applications. Both electromagnetic and hadronic physics processes and models within the prebuilt Geant4 physics lists are tested. The tests included in G4-Med are executed on the CERN computing infrastructure via the use of the geant-val web application, developed at CERN for Geant4 testing. The physical observables can be compared to reference data for benchmarking and to results of previous Geant4 versions for regression testing purposes. RESULTS: This paper describes the tests included in G4-Med and shows the results derived from the benchmarking of Geant4 10.5 against reference data. DISCUSSION: Our results indicate that the Geant4 electromagnetic physics constructor G4EmStandardPhysics_option4 gives a good agreement with the reference data for all the tests. The QGSP_BIC_HP physics list provided an overall adequate description of the physics involved in hadron therapy, including proton and carbon ion therapy. New tests should be included in the next stage of the project to extend the benchmarking to other physical quantities and application scenarios of interest for medical physics. CONCLUSION: The results presented and discussed in this paper will aid users in tailoring physics lists to their particular application.
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Benchmarking , Física , Radiometria , Simulação por Computador , Método de Monte CarloRESUMO
Materials that possess nontrivial topology and magnetism is known to exhibit exotic quantum phenomena such as the quantum anomalous Hall effect. Here, we fabricate a novel magnetic topological heterostructure Mn4Bi2Te7/Bi2Te3 where multiple magnetic layers are inserted into the topmost quintuple layer of the original topological insulator Bi2Te3. A massive Dirac cone (DC) with a gap of 40-75 meV at 16 K is observed. By tracing the temperature evolution, this gap is shown to gradually decrease with increasing temperature and a blunt transition from a massive to a massless DC occurs around 200-250 K. Structural analysis shows that the samples also contain MnBi2Te4/Bi2Te3. Magnetic measurements show that there are two distinct Mn components in the system that corresponds to the two heterostructures; MnBi2Te4/Bi2Te3 is paramagnetic at 6 K while Mn4Bi2Te7/Bi2Te3 is ferromagnetic with a negative hysteresis (critical temperature ~20 K). This novel heterostructure is potentially important for future device applications.
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Charge acceleration during an intense light field application to solids attracts much attention as elementary processes in high-harmonic generation and photoelectron emission. For manipulating such attosecond dynamics of charge, carrier-envelope-phase (CEP: relative phase between carrier oscillation of light field and its envelope function) control has been employed in insulators, nanometal and graphene. In superconducting materials, collective control of charge motion is expected because of its strongly coherent nature of quasi-particles. Here we report that, in a layered organic superconductor, a non-linear petahertz current driven by a single-cycle 6 femtosecond near infrared field shows up as second harmonic generation (SHG), which is in contrast to the common belief that even harmonics are forbidden in the centrosymmetric system. The SHG represents a CEP sensitive nature and an enhancement near the superconducting temperature. The result and its quantum many-body analysis indicate that a polarized current is induced by non-linear acceleration of charge, which is amplified by superconducting fluctuations. This will lead to petahertz functions of superconductors and of strongly correlated systems.
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BACKGROUND AND PURPOSE: The detection rate of diffusion-weighted (DWI) hyperintense lesions varies widely in patients with transient global amnesia (TGA). The aim was to examine the association of hyperintense lesions on DWI magnetic resonance imaging (MRI) with patient characteristics, precipitating factors, clinical presentation and MRI settings in patients with TGA. METHODS: In this multicenter retrospective observational study, using the standardized diagnosis entry system of electronic health records of four tertiary medical centers in the Kansai district of Japan, TGA patients (n = 261) who underwent brain MRI within 28 days of onset were examined. When the onset time was unavailable, the discovery time was used. RESULTS: Diffusion-weighted hyperintense lesions were observed in 79 patients (30%). There were no significant differences in age, sex, vascular risk factors, precipitating factors or clinical presentation between patients with and without DWI lesions. The detection rate increased linearly 24 h after onset and then reached a plateau of 60%-80% by 84 h. After 84 h, the detection rate decreased rapidly. In a multivariate logistic regression model, MRI examination 24-84 h after onset (odds ratio 7.00, 95% confidence interval 3.50-13.99) and a thin-slice (≤3 mm) DWI sequence (odds ratio 7.59, 95% confidence interval 3.05-18.88) were independent predictors of DWI lesions. CONCLUSIONS: This study suggests that DWI hyperintense lesions in TGA are not associated with patient characteristics and clinical presentation. Brain MRI examination 24-84 h after onset and thin-slice DWI sequences enhance the detection of DWI lesions in TGA patients.
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Amnésia Global Transitória , Amnésia Global Transitória/diagnóstico por imagem , Hipocampo , Humanos , Japão/epidemiologia , Imageamento por Ressonância MagnéticaRESUMO
Plasma window is a feasible device as an atmosphere-vacuum interface, which can withstand energetic particle beams. It is, however, essential to enlarge the diameter to several tens of millimeters for actual beam passing in the accelerator applications. The pressure separation performance and discharge voltage V current I characteristics should be investigated in detail to design the plasma window for each purpose. Therefore, a cascade arc discharge device with a diameter of up to 20 mm was developed, and its characteristics as a function of diameter were examined. As a result, with an increase in the channel diameter, the discharge pressure that was achieved decreased, whose values were smaller compared with the values by the prediction formula, assuming the viscous gas flow with a constant plasma temperature. It showed that the bulk plasma temperature for the larger discharge channel was low because of the low-current density over the channel. Furthermore, the transition of the V-I slope was observed with an increase in the diameter.
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The cardiac conduction system was examined histologically in 12 canine cases of lymphocytic myocarditis with complete atrioventricular (AV) block. Histological analysis showed active myocarditis characterized by intense infiltration of mononuclear cells, primarily lymphoid, associated with degeneration and necrosis of the adjacent cardiomyocytes. Additionally, there was healing or healed myocarditis manifested by disappearance of cardiomyocytes and replacement fibrosis. This destructive inflammatory process of lymphocytic myocarditis involved the whole of the AV conduction system, resulting in loss and deletion of the conduction fibres, as well as the myocardium of all chambers. Such total or subtotal destruction of the AV conduction system caused by the inflammatory changes was thought to have set the stage for blocking AV conduction of cardiac impulses, but the aetiology of the lymphocytic myocarditis was not elucidated.
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Bloqueio Atrioventricular/veterinária , Doenças do Cão/patologia , Miocardite/veterinária , Animais , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/patologia , Cães , Feminino , Masculino , Miocardite/complicações , Miocardite/patologiaAssuntos
Receptores ErbB , Nevo , Neoplasias Cutâneas , Criança , Receptores ErbB/genética , Humanos , Masculino , Mutação/genética , Nevo/genética , Neoplasias Cutâneas/genéticaRESUMO
AIM: In patients with a previous history of rectal anastomotic leakage (AL), the surgical indications and timing for closure of a diverting stoma have to be carefully judged. Even if AL has apparently healed before stoma closure, re-leakage may occur after closure. The aim of this study was to determine the incidence and risk factors for recurrent AL following stoma closure. We also examined the treatment strategies aiming to minimize the risk of recurrent AL. METHODS: From January 2009 to December 2016, 1008 patients underwent sphincter-saving surgery [low anterior resection, all-sphincter-preserving rectal resection with hand-sewn coloanal anastomosis (CAA) and intersphincteric resection (ISR)] for primary rectal cancer with curative intent at our hospital. A total of 69 patients with AL with a Clavien-Dindo Grade III or more who subsequently underwent closure of a diverting stoma were retrospectively reviewed for this study. RESULTS: The incidence of recurrent leakage after stoma closure in this series was 13% overall with an incidence of 25% in the CAA/ISR group and 5% in the low anterior resection group. Significant risk factors included hand-sewn anastomosis (P = 0.0257) compared to stapled anastomosis, ischaemia at the anastomotic site as the cause of initial AL (P < 0.001) and a shorter interval between confirmation of healing and stoma closure (P = 0.00952). CONCLUSION: Ischaemia at the anastomotic site was the main risk factor for recurrent leakage, particularly after CAA/ISR. Additional treatment options before stoma closure should be considered to avoid re-leakage in such cases.
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Canal Anal/cirurgia , Fístula Anastomótica/epidemiologia , Colo/cirurgia , Isquemia/complicações , Estomas Cirúrgicos/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/etiologia , Fístula Anastomótica/cirurgia , Bases de Dados Factuais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Protectomia/efeitos adversos , Estudos Prospectivos , Neoplasias Retais/cirurgia , Recidiva , Estudos Retrospectivos , Fatores de RiscoRESUMO
OBJECTIVES: An operations leader (OL) takes an important role in occupational health management for radiation decontamination workers in Japan, and candidates for the position must participate in a training session to acquire the necessary knowledge as required by law. However, it has not been clarified whether the candidates for the OL position actually possess accurate knowledge regarding occupational health management for such work after the training session. We, therefore, aimed at examining the current occupational health management knowledge among the candidates and investigating factors related to the knowledge, with hypothesis that possession of accurate knowledge is associated with prior experience of having worked in radiation decontamination. DESIGN: A cross-sectional study. SETTING: The training sessions held by Fukushima Prefecture Labor Standard Associations in Fukushima, Japan, in 2017. PARTICIPANTS: Eighty male candidates participated in the training sessions. OUTCOME: The number/proportion of correct answers to the questions regarding occupational health management, such as those on working environment management, control of operations and health management. RESULTS: The proportion of those who possessed accurate knowledge regarding working environment management, control of operations and health management was 68.8%, 55.0% and 51.2%, respectively. Experience of radiation decontamination work was associated with the possession of inaccurate knowledge regarding working environment management (OR 0.140 (95% CI 0.042 to 0.464)), and the uncertainty of future radiation decontamination work schedules in difficult-to-return zones was associated with the possession of accurate knowledge regarding health management (OR 4.344 (95% CI 1.509 to 12.50)). CONCLUSIONS: Previous experience in radiation decontamination work may hinder the ability to acquire accurate information regarding working environment management among candidates for an OL position. To promote adequate occupational health management for radiation decontamination workers, it is required to establish an effective instructional method for the OL candidate training sessions with consideration of previous relevant experience.
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Descontaminação , Gestão do Conhecimento , Liderança , Doenças Profissionais/psicologia , Saúde Ocupacional/educação , Adulto , Ansiedade/psicologia , Estudos Transversais , Acidente Nuclear de Fukushima , Humanos , Japão , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Centrais Nucleares , Exposição Ocupacional , Exposição à Radiação , Inquéritos e Questionários , Local de TrabalhoRESUMO
An important factor controlling tree species diversity is conspecific density dependence (CDD). Adult trees associated with arbuscular mycorrhiza (AM) and ectomycorrhiza (ECM) can exhibit negative and positive CDD effects on conspecific recruitment, respectively. However, the extent to which these mycorrhizal associations affect spatial distributions of individual trees and their relative abundances within forests through CDD remains uncertain. We analysed changes in spatial correlations between adults and conspecific juveniles at different growth stages of five hardwood species in a 6-ha plot of an old-growth forest using a point pattern analysis. The clump sizes of large individuals were also evaluated using the Iδ index (a measure of individual dispersion) in 24 species. In two AM-associated species, juveniles were distributed at greater distances with increasing size or were always distributed at a distance from adults, resulting in small clumps of adults. In contrast, juveniles of two ECM-associated species were distributed close to adults during early or late growth stage, resulting in large clumps of adults. Juveniles of an ECM-associated species disappeared with increasing size, probably due to shade intolerance. In 24 tree species with large numbers of individuals within a plot, the relative basal area was related to both mycorrhizal type and maximum diameter, suggesting that the relative abundance of a species is largely related to its mycorrhizal associations and maximum plant size. This study strongly demonstrated that mycorrhizal associations play an important role in determining the spatial distribution patterns and community structure of tree species through CDD.