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Background Early mobility therapy in the intensive care unit (ICU) is widely employed to improve the physical function and prognosis of patients with critically ill. On the other hand, patients who undergo cardiovascular surgery frequently suffer from disabilities after ICU care due to their cardiopulmonary conditions and treatments. However, few studies have reported the procedures and assessments of acute-phase rehabilitation in these patients. Recently, the Perme ICU Mobility Score (Perme Score) was developed as a reliable tool to assess comprehensive mobility status of patients in the ICU. We hypothesised that the Perme Score is a useful tool for assessing the mobility levels in the ICU and predicting clinical outcomes in patients undergoing acute-phase rehabilitation after cardiovascular surgery. Purpose To investigate the associations between the Perme Score within the second days after cardiovascular surgery and the patients' clinical outcomes, including physical function and the incidence of clinical events. Methods We studied 224 consecutive patients (34.4% female; aged 65±13 years) who were admitted to the ICU of a tertiary academic hospital after cardiac and/or major vascular surgery. Clinical characteristics including patient profiles, comorbidities, surgical details and APACHE II and SOFA scores were evaluated on ICU admission. The Perme Score contains categories on mental status, potential mobility barriers, muscle strength and mobility level, with higher scores indicating greater activity levels in the ICU. We assessed the Perme Score within the second days after the surgery. As a physical function at hospital discharge, we measured the six-minute walk distance (6MWD). The primary endpoint was a composite outcome of the number of all-cause mortality and/or all-cause unplanned readmission. We analysed the associations of the Perme Score with the 6MWD and the incidence of clinical events using multiple regression analysis and multivariate Poisson regression analysis, respectively. Results After adjusting for clinical confounding factors, a higher Perme Score was an independent factor of a higher 6MWD (Table 1). During the median follow-up period of 1.3 years, 51 cases of all-cause mortality/readmission occurred in 37 (16.5%) patients, with an incidence rate of 18.6/100 person-years. In the multivariate Poisson regression analysis, even after adjusting for the severity score in the ICU, a higher Perme Score was significantly and independently associated with lower rates of all-cause clinical events (adjusted incident rate ratio: 0.96, 95% confidence interval: 0.93–0.99, P=0.008, Figure 1). Conclusions The Perme Score within the second days after cardiovascular surgery is correlated with physical function at hospital discharge and the incidence of clinical events after discharge. Thus, a comprehensive assessment of acute-phase rehabilitation after cardiovascular surgery may be useful in predicting clinical outcomes. Funding Acknowledgement Type of funding sources: None.

Introduction The emerging interdisciplinary field of cardio-oncology is of interest to clinicians because a history of cancer or cancer treatment is considered a severe risk factor for cardiovascular disease (CVD). Both cancer and CVD can reduce skeletal muscle mass; together, they can lead to a poorer prognosis. However, it is unclear whether a patient's cancer history can lower physical function and lead to a poor prognosis with the coexistence of cancer history and physical dysfunction in patients with CVD. This study aimed to identify the relationship between cancer history and physical function, as well as the prognostic value of their combination, in patients with CVD. Methods We reviewed 3,640 patients with CVD (mean age, 67.9±13.5 years) who underwent physical-function tests (gait speed and 6-min walking distance [6MWD]). We performed multivariate linear regression analysis to assess potential associations between cancer history and physical-function tests in patients with CVD. Additionally, we used the Kaplan–Meier curve and Cox regression analyses to assess survival and prognostic significance for patients divided into four groups according to the presence or absence of cancer history and high or low physical function. Results In multivariate linear regression analysis, cancer history was independently associated with lower gait speed and 6MWD (gait speed, P=0.048 and 6MWD, P=0.040). A total of 581 deaths occurred over a median follow-up period of 3.08 years (interquartile range: 1.36–5.27). For all-cause mortality, patients with a history of cancer and reduced physical function were found to have a significantly higher mortality risk even after adjusting for several covariates (gait speed, HR: 1.66, P=0.003 and 6MWD, HR: 1.71, P=0.003). Conclusion Cancer history was correlated with physical dysfunction in patients with CVD. Moreover, the coexistence of cancer history and physical dysfunction resulted in poorer prognosis in patients with CVD. Funding Acknowledgement Type of funding sources: None.

Background Sarcopenia is highly prevalent in patients with heart failure (HF) and is associated with a poor prognosis and a low quality of life. On the other hand, cardiac rehabilitation (CR) has improved clinical outcomes in patients with HF. However, the clinical impact of improving sarcopenia after CR in patients with HF is unclear. Purpose This study aimed to investigate whether improved or not improved sarcopenia is associated with mortality and the number of readmissions for HF in patients with HF. Methods We reviewed a total of 647 patients who were admitted for HF treatment and underwent a 5-month outpatient CR after discharge. We assessed sarcopenia at discharge, 3 months and 5 months of outpatient CR, based on Asian Working Group for Sarcopenia 2019 diagnostic criteria. For subjects assessed for sarcopenia at both 3 and 5 months, the assessment results at 5 months were used in the analysis. All patients were classified according to the presence of sarcopenia at baseline and the time of outpatient CR as follows: patients without sarcopenia were the robust group, those with sarcopenia at baseline but improving at the time of outpatient CR were the improved group, and those with sarcopenia at baseline and at the time of outpatient CR were the non-improved group. To assess mortality between the robust, improved, and non-improved groups, we used multivariate Cox proportional hazard analyses. Additionally, we used multivariate Poisson regression analyses to assess the number of readmissions for HF between the robust, improved, and non-improved groups. Moreover, as a subgroup analysis, the same Cox proportional hazards analysis was evaluated by categorizing patients with HF with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). The endpoint was all-cause death or rehospitalization for HF. Results Of the 647 patients, 381 (58.9%) were in the robust group, 103 (15.9%) were in the improved group, and 163 (25.2%) were in the non-improved group. In multivariate Cox proportional hazard analyses, the non-improved group had significantly higher mortality compared to the robust group [adjusted hazard ratio (HR): 2.71, 95% confidence interval (CI): 1.58–4.66] after adjusting for severity of HF (Figure 1-A). In addition, both HFrEF and HFpEF groups had significantly higher mortality in the non-improved group compared to the robust group (HFrEF; HR: 2.41, 95% CI: 1.22–4.76, HFpEF; HR: 2.86, 95% CI: 1.01–8.09) (Figure 1-B and 1-C, respectively). In multivariate Poisson regression analyses, the non-improved group had a high incidence of readmissions for HF compared to the robust group (adjusted incident rate ratio: 1.56, 95% CI: 1.20–2.02) (Figure 2). Conclusions A lack of improvement in sarcopenia after CR in patients with HF has affected the life expectancy and the number of readmissions for HF. Funding Acknowledgement Type of funding sources: None.

Introduction While the major outcome of cardiac rehabilitation for heart failure (HF) is the improvement of exercise tolerance, prognosis, and quality of life, instrumental activities of daily living (IADL) has also been focused on as one of the its outcomes. IADL has been reported to be associated with all-cause mortality and quality of life in community-dwelling people and in patients with stable heart disease, but no report has examined the relationship between IADL after cardiac rehabilitation for HF and prognosis. In addition, it is assumed that sex differences may affect the frequency of performing each component of IADL, but there are no reports examining the association with prognosis by sex. Purpose The present study aimed to investigate the sex differences in frequency of IADL and its impact on outcomes. Methods We retrospectively studied 490 consecutive patients who were admitted due to acute decompensated HF and participated in outpatient cardiac rehabilitation after discharge. The study was performed in accordance with the tenets of the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of our institution. IADL frequency was assessed using the questionnaire-based Frenchay Activities Index (FAI). The primary endpoint was all-cause death and secondary endpoint was combined events (all-cause death and/or readmission due to HF). We performed the Kaplan–Meier and log-rank tests and multivariable Cox regression analysis to evaluate the prognostic predictive capability of the FAI. Results The study population had a median age of 69 (interquartile range [IQR]: 58–76) years, and 33.9% of patients were females. The median FAI score was 24 (IQR: 16–29) points. According to the Youden index based on the area under the curve calculated by the receiver operating characteristics curve, the cut-off values of FAI for all-cause death in all-over, females, and males were 23, 22, and 23 points, respectively. Over a median follow-up period of 4.8 years (IQR: 2.3–6.6 years), all-cause death and combined events were occurred in 95 (19.4%) and 213 (43.5%), respectively. After adjustment for several pre-existing prognostic factors, IADL assessed by the FAI was independently associated with all-cause mortality (hazard ratio [HR]: 0.961, 95% confidence interval [CI]:0.937–0.986) and combined events (HR: 0.968, 95% CI: 0.952–0.985), respectively. In addition, there was no interaction between sex in prognostic capability (P=0.664). Conclusion Lower IADL frequency assessed by FAI at the end of outpatient cardiac rehabilitation was shown to be associated with poorer prognosis in patients with HF, regardless of sex. The IADL level is generally higher in females than in males but seems to be a useful marker for risk stratification at the end of cardiac rehabilitation in both females and males. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid [JSPS KAKENHI Grant Number JP 19K19884]

Background Early rehabilitation in the intensive care unit (ICU), including early mobility therapy, is known to improve the clinical outcomes in patients with critically ill. However, the effectiveness of acute-phase cardiovascular rehabilitation (CR) during ICU treatment have not been thoroughly evaluated in patients with cardiovascular disease (CVD). Purpose We aimed to investigate the trends and outcomes of acute-phase CR in the ICU for patients with CVD, including in-hospital and long-term clinical outcomes. Methods We reviewed 1948 consecutive patients with CVD admitted to tertiary academic ICU at a university hospital. Patients were arbitrarily assessed by an ICU team consisting of medical and surgical doctors, nurses and physiotherapists within 24 hours after admission to ICU to discover whether their rehabilitation could be initiated according to the specific clinical trial and statement. As clinical characteristics, disease aetiology, comorbid conditions, and ICU treatment were obtained from an electronic database. We evaluated the probability of return to walking independence and return to home as in-hospital clinical outcomes. All patients were followed for five years and investigated all-cause and cardiovascular events after hospital discharge as long-term clinical outcomes. The associations between the implementation of CR during ICU treatment (ICU-CR) and clinical outcomes were evaluated using propensity score-matched analysis with adjustment for clinical characteristics in all matched patients and various subgroups, including aged >65 years, surgical patients, emergency, and length of ICU stay ≥48 hours. Results Out of studied patients, 1092 patients received ICU-CR, the number of which positively correlated with year-trend (r=0.986, P Conclusions The implementation of acute-phase CR in the ICU increased with year-trend, considered beneficial to improve in-hospital and long-term clinical outcomes in patients with CVD and various subgroups of relatively severe disease conditions. Funding Acknowledgement Type of funding sources: None.

Background Patients with heart failure (HF) have a high prevalence of liver function abnormalities such as bilirubin abnormalities. However, the relationship between abnormalities of direct bilirubin (DB), a fraction of total bilirubin, and dynapenia are unclear, and the effect of the coexistence of both on the prognosis of patients with HF remains unclear. Purpose This study investigated the association between total/direct bilirubin and dynapenia, a muscle weakness syndrome. Moreover, we considered the effect of the combination of high DB and dynapenia on increased mortality. Methods In this retrospective cohort study, we reviewed patients with HF for whom we assessed total bilirubin, DB, handgrip strength, and leg strength at discharge, which were further evaluated to determine the presence of dynapenia. Dynapenia was defined by the lower handgrip strength and leg strength. Low handgrip strength was defined as Results Among 853 inpatients enrolled, high DB was identified in 147 and dynapenia in 377 (44.2%) patients. Multiple regression analysis showed that high DB was independently associated with decreased grip and leg strengths (grip strength, P=0.027; leg strength, P=0.002). Furthermore, after adjusting for covariates, the high DB group (odds ratio: 1.800, 95% confidence interval [CI]: 1.203–2.695, P=0.004) was significantly associated with dynapenia compared to the low DB group. During the follow-up period, 189 patients died (median, 1.77 years; interquartile range, 0.64–3.81 years). The risk of death was significantly higher in the high DB/dynapenia group than in the low DB group, even after adjusting for the severity of HF (hazard ratio: 2.610, 95% CI: 1.680–4.051, P Conclusions High DB is associated with muscle weakness in patients with HF and affects patient prognosis. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): This work was partially supported by JSPS KAKENHI.

Introduction Exercise intolerance in patients with heart failure (HF) is a strong indicator of a poor prognosis. As the respiratory impairment in HF patients, the small airway is reportedly more susceptible than central airways, which results in increased airway resistance and may cause poor outcomes. However, the impact of small-airway disease (SAD) on exercise intolerance and prognosis in patients with HF is still unclear. Purpose We investigated the associations between SAD and exercise intolerance in patients with HF, and the clinical significance of SAD for long-term clinical events with a reduced or preserved ejection fraction. Methods We reviewed 1015 patients with HF (mean age, 66.9±14.6 years; male, 64.5%) admitted for medical treatment. Patients with a prior history of chronic respiratory disease or an obstructive lung pattern – defined as the forced expiratory volume (%) in 1 s relative to Result SAD was observed in 479 (47.2%) patients. LVEF subgroups included 458 (45.1%) and 518 (51.0%) patients with LVEF Conclusion This study is the first to reveal that SAD is associated with exercise intolerance in patients with HF regardless of LVEF. Moreover, SAD may have a predictive significance for long-term outcomes in patients with HF and subgroups with reduced, but not preserved ejection fraction. Funding Acknowledgement Type of funding sources: None.

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science (JSPS) KAKENHI Background Owing to the spread of coronavirus disease 2019 (COVID-19), people have refrained from going out unnecessarily and have been maintaining social distance. These new lifestyle approaches have affected people physically, psychologically, and socially. Patients with heart failure (HF) are more likely to have social frailty, physical frailty, cognitive impairment, and depressive symptoms, and an overlap of these conditions leads to adverse events. Therefore, multi-domain assessment and understanding of the condition of patients with HF are important for disease management. The spread of COVID-19 is a predicted risk factor for these events, but its impact in patients with HF has not been investigated. Purpose We investigated whether the spread of COVID-19 is associated with the development of the multi-domain of frailty in patients with HF. Methods Patients who were independent in their daily activities before admission were included in the study. The presence of social frailty (Makizako’s five items), physical frailty (Fried phenotype model), cognitive impairment (Mini-Cog), and depressive symptoms (the Patient Health Questionnaire-2) in patients with HF were assessed at hospital discharge. Logistic regression analyses were used to examine the impact of the spread of COVID-19 on the development of the multi-domain of frailty in patients with HF. Results We included 482 patients in this study. Median patient age was 74 years, and 64.5% were male. In multivariate logistic regression analyses, the spread of COVID-19 was significantly associated with the development of social frailty (odds ratio [OR]: 1.15, 95% confidence interval [CI]: 1.02–1.30) and depressive symptoms (OR: 1.14, 95% CI: 1.02–1.27) but not with the development of physical frailty (OR: 1.24, 95% CI: 0.51–3.02) and cognitive impairment (OR: 1.72, 95% CI: 0.80–3.73). Conclusion The spread of COVID-19 was associated with the development of social frailty and depressive symptoms in patients with HF. Evaluation of social frailty and depressive symptoms during hospitalization would support disease management and understand their social and psychological conditions specific to the spread of COVID-19.

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI Grant Background Sarcopenia is a chronic condition that is characterized by the loss of skeletal muscle mass with declining muscle strength and/or performance that occurs gradually with aging. It has been reported that sarcopenia is highly prevalent in patients with heart failure (HF) and is a poor prognostic factor. Therefore, it is important to accurately assess skeletal muscle mass in patients with HF. However, there are no reports that have simultaneously examined different skeletal muscle mass metrics as factors in the prognosis of HF patients. Purpose The purpose of this study is to examine if the different skeletal muscle mass metrics are associated with the prognosis of HF patients. Methods We examined a total of 869 patients with HF, aged ≥20 years (73 [63, 80] years; 537 males), who were admitted to our hospital and participated in an inpatient cardiac rehabilitation program. We used skeletal muscle mass index (SMI) as measured by bioelectrical impedance analysis (BIA), mid-upper arm circumference (MUAC), arm muscle circumference (AMC), and calf circumference (CC) as metrics of skeletal muscle mass. The primary outcome was all-cause deaths, and secondary outcome was HF readmission. To investigate the association between each skeletal muscle mass metric and prognosis, patients were divided into three groups according to the tertiles of SMI, MUAC, AMC, and CC. In addition, cumulative event rates of survival curves, Gray test, and Fine & Gray test were performed to evaluate the prognostic predictive capability. Results Over a median follow-up period of 0.9 years (interquartile 0.4–1.9) years, a total of 80 deaths and 195 HF readmissions occurred in the patients. Cumulative event rates of survival curves and Gray test showed that there was a significant decrease in all-cause mortality and HF readmission in the high MUAC group and high AMC group compared to their respective low groups (P < 0.05). Fine & Gray test after multivariate adjustment showed significantly better prognosis in the high MUAC group and high AMC group compared to their respective low groups (All-cause mortality: high MUAC group, subdistribution hazard ratio [sHR] = 0.42, 95% confidence interval [CI] = 0.20-0.88, P < 0.05; high AMC group, sHR = 0.34, 95%CI = 0.16-0.72 P < 0.05, HF readmission: high MUAC group, sHR = 0.69, 95%CI = 0.47-1.00, P < 0.05; high AMC group, sHR = 0.63, 95%CI = 0.43-0.93, P < 0.05). Conclusion Patients with HF who maintained high MUAC and high AMC had a good prognosis. CC and SMI were not associated with the prognosis of HF patients. This suggests the importance of evaluating MUAC and AMC in HF patients.

Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI Background It is widely known that patients with acute coronary syndrome (ACS) are at increased risk of nonalcoholic fatty liver disease (NAFLD), which is linked to sarcopenia and physical dysfunction. However, the relationship between metabolic dysfunction-associated fatty liver disease (MAFLD) and physical dysfunction remains unclear. Purpose The purpose of this study was to investigate the prevalence of MAFLD in patients with ACS to assess the relationship between MAFLD and muscle strength, walking speed, and 6-minute walking distance (6 MWD). Methods We reviewed patients with ACS who were assessed for hepatic steatosis using the fatty liver index, and the results were further assessed to determine the presence of MAFLD. Multiple regression analysis was used to examine the association between MAFLD and physical function. Results Among 479 enrolled hospitalized patients, MAFLD was identified in 234 (48.9%) patients. We conducted a multiple regression analysis in which MAFLD was independently associated with lower leg strength, gait speed, and 6 MWD (leg strength, P = 0.023; gait speed, P = 0.002 and 6 MWD, P = 0.017). Furthermore, having more metabolic impairment was still associated with lower physical function decline (leg strength, P for trend = 0.002; gait speed, P for trend = 0.019 and 6 MWD, P for trend = 0.003). Conclusions MAFLD is common in hospitalized patients with ACS, and most patients with MAFLD have many overlapping metabolic abnormalities. MAFLD is associated with impaired physical function, and the greater the number of overlapping metabolic abnormalities, the worse the motor function.

Introduction The coexistence of heart failure (HF) and frailty leads to a worse prognosis. Frailty is generally diagnosed using the Fried criteria. To assess whether patients are frail according to the Fried scale, face-to-face physical examinations are required. However, with the COVID-19 pandemic, to avoid the spread of the virus in hospitals, it is important to screen hospitalized patients for frailty without contact. Therefore, non-contact measurement methods, such as questionnaires, should be used to screen for frailty in clinical practice. The FRAIL scale is a questionnaire used to screen for frailty. There are no studies regarding the consistency of the FRAIL scale with the Fried criteria, the impact on mortality, and physical dysfunction in elderly patients with HF. Purpose We investigated whether the FRAIL scale questionnaire is consistent with the Fried criteria, predicts all-cause mortality, and reflects physical dysfunction in patients with HF. Methods The present study was secondary analysis of FRAGILE-HF, a cohort study that enrolled participants from 2016 to 2018 and followed up for 1-year of discharge. A prospective multicenter cohort study in which 15 hospitals in Japan (8 university hospitals and 7 non-university teaching hospitals) participated. We prospectively enrolled 1332 consecutive hospitalized patients with HF ≥65 years old and analyzed 1028 patients after excluding 304 patients with missing data on the FRAIL scale. The FRAIL scale, the Fried model, and physical function were measured before discharge. The endpoint was all-cause mortality. Results According to the FRAIL scale, 459 (44.6%) and 491 (47.8%) were classified as frail and pre-frail, respectively. The Kappa coefficient between the FRAIL scale and the Fried criteria were 0.39 (95% confidence interval [CI]: 0.34–0.44; P value: Conclusions The FRAIL scale had moderate consistency with the Fried criteria, predicted all-cause mortality, and reflected clinically important physical dysfunction. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): the Japan Society for the Promotion of Science Grant-in-Aid (JSPS KAKENHI, Grant Number 19K19884)

Background Impella has been increasingly used in patients with cardiogenic shock (CGS). Target values for clinical indices for appropriate management of Impella have not yet been established. Purpose We aimed to elucidate the association between heat rate (HR) during Impella treatment in patients with CGS and clinical outcomes. Methods and results We retrospectively evaluated 62 patients (68±14 years; male 77%) with CGS receiving temporary circulatory support with the Impella between February 1, 2019, and February 31, 2021. The primary end point was 30-day mortality. Clinical characteristics, laboratory and hemodynamic markers at implantation of Impella (baseline), 12, 24 hr after implantation, and removal of Impella were assessed. There were 28 patients with concomitant use of extracorporeal membrane oxygenation (ECMO). Treatment periods using Impella were 8±6 days. After excluding 11 patients who died during Impella support, the relationship between clinical indicators at each time points and 30-day mortality was evaluated. There were 22 patients (43%) with 30-day mortality. Factors associated with 30-day mortality were: female, ECMO, higher 24-hr lactate level, lower 24-hr cardiac power output, and higher HR at removal. Lower HR of ≤81 bpm at removal was found to most accurately predict lower 30-day mortality (Figure 1). Higher increases in dose of beta-blockers during Impella support and lower absolute doses of norepinephrine at removal were correlated with decreases in HR during Impella support. Conclusions In patients with CGS treated with Impella, lower HR at removal was associated with lower incidence of 30-day mortality. Lowering HR during Impella treatment was recognized as a simple indicator for favorable clinical outcomes in patients with CGS. It was suggested that chronotropic interventions during Impella treatment may be novel therapeutic options in patients with CGS. Funding Acknowledgement Type of funding sources: None. Figure 1

In an attempt to establish tobacco stalks as a raw material for biomass resources, a preliminary evaluation of their chemical and physical properties in comparison with wood species prior to their utilization for various wood-based applications is indispensable and, hence, the main object of this study.

New five-way hybrid power dividers are synthesized by making use of two sections of five-wire uncoupled transmission-lines of equal length with isolation resistors which are connected by the ends of the neighboring wires. As for the theoretical analysis of five-way planar HPD, the isolation characteristics among five ports show more than 20 dB, and the VSWR's of six ports show less than 1.4 in 2:1 bandwidth.

NTT is developing a family of optical subscriber systems, named IFOS (Integrated Fiber-Optic Subscriber System). The scenario of upgrading fiber-in-the-loop (FITL) systems toward a full B-ISDN system using IFOS is discussed. A basic subscriber system model is introduced to separate service independent portion (access system) from the subscriber system. Based on the proposed model, upgrading of the service independent access system using asynchronous transfer mode (ATM) is discussed. The system configuration of IFOS is also addressed. >

Economical B-ISDN services can be realized with the passive double star (PDS) system which shares fiber cables and telephone office equipment among several users. PDS system flexibility can be enhanced by using the ATM transmission technique. Our assumption is that POTS and narrowband ISDN (N-ISDN) are services that must be supported. This paper proposes a PDS system based on the ATM transmission technique (A-PDS) and shows how to transmit POTS and N-ISDN as well as B-ISDN. >

This paper presents a practical design method as well as optimal design parameters for a 155 Mb/s ATM-PON access system. In this system, burst signals from multiple optical network units are received by the subscriber line terminal with various level and bit timing values. Receiver parameters, which are conventionally optimized for continuous or low bit rate bursts, have to be optimized for high bit rate and short burst transmission. This paper presents bandwidth, clock phase number, timing detection method, and noise reduction method for short burst signals. This design is implemented and found to work successfully.

This paper describes design concept of an STM-based high speed digital FTTH system that can provide not only high speed digital end-to-end service, but also digital video services such as distribution video and video-on-demand services. The configuration and protocol of the video service control are also discussed. The node functions needed for video services are discussed considering system introduction when the density of video-on-demand customers is low. A prototype system offering bi-directional STM-1 transmission is also described. >

The paper proposes a new passive double star (PDS) duplex configuration that enables either single or duplex wiring in customer buildings. The automatic protection switching algorithm using this duplex configuration is also discussed. The paper also proposes an orderly and quick round trip delay control algorithm of plural optical network units (ONUs) of the PDS system. The control algorithm is required in the activation process of an automatic protection switching, since the new duplex configuration requires a cold stand-by mechanism in the transmission equipment. This algorithm uses only one shared channel by ONUs to minimize the waste of transmission capacity.

The authors propose and examine the distribution composition of an XC-MUX (crossconnect multiplexer) with the aim of applying it to an optical transfer network. A numerical analysis confirms that the proposed composition is able to efficiently cope with demand changes on small-scale circuits. A distributed cooperative algorithm, including a self-healing algorithm, is proposed, which can also be applied to distributed XC-MUXs. The algorithm can efficiently use spare paths even in the case of nonideal topologies and multiple failures. >

The path multiplexing architecture for optical subscriber systems that are constructed with synchronous transfer mode (STM) techniques is discussed. A novel concept, the virtual sub-container (VSC), is proposed to realize multiple network access. The VSC multiplexing method will make it possible to offer various services flexibly and inexpensively. Configuration of the digital service unit (DSU) based on VSC and the user network interface, and ideas for operation, administration, and maintenance are shown. The necessity of considering the introduction of asynchronous transfer mode (ATM) is also discussed. >

This paper clarifies the bandwidth characteristics of a VAD-fabricated optical line constructed with short-length optical fibers. The refractive index profiles of these optical fibers are slightly distorted from the ideal profile. Their bandwidth characteristics are calculated and measured under the overfill mode distribution (OMD) and the equilibrium mode distribution (EMD) excitations. As a result, some of the optical fibers are shown to have extremely narrow bandwidths at the short fiber length under OMD excitation as compared with those under EMD excitation. The concatenation factor of the optical line consequently becomes a smaller value than that of an optical line constructed with long-length optical fibers. In addition, the measurement results of the optical subscriber transmission line field trial are shown to be in good agreement with those obtained in this paper.

This paper clarifies crosstalk dependence on fiber parameters to ensure proper multicore or bunch fiber design. The analysis of crosstalk between adjacent graded-index optical fibers is accomplished by extending the meridional quasi-ray tracing procedure, whose analysis method is based on the total reflection of waves in a multilayered medium. Crosstalk attenuations in several bunch fibers with various parameters are measured. Crosstalk inclination measured for fiber parameters agrees with the analyzed results. Equations which express the approximate relationship between crosstalk and fiber parameters are derived from the analyzed results. The experimental findings can be applied to realize high-count high-density low-cost cable.

A new n-way planar hybrid power divider (henceforth HPD) and an n-way coaxial-type HPD are proposed, and the synthesis methods of three-way and four-way planar HPD's are shown. As for the three-way planar HPD, the isolation characteristics among three ports show more than 20 dB, and the VSWR'S of four ports show less than 1.4 in 2:1 bandwidth. The experimental characteristics are in good agreement with the theoretical analysis.

Parameters of bunched GI-optical fiber for use in the 1.3- μm wavelength subscriber line are designed. Suitable fiber parameters were determined mainly from studies concerning transmission loss and crosstalk characteristics. A core diameter around 45 μm and a relative refractive-index difference range from 1.2 to 1.5 percent were found to be suitable for the allowable cladding diameter range from 70 to 90 μ determined by crosstalk and economical considerations. It is also found that a transmission line composed of bunched optical fibers with suitably designed parameter range exhibits a loss level comparable to that composed of the conventional monocore fiber.

An optical branching component is proposed for coupling bunched optical fiber to mono-core optical fibers and the component loss and crosstalk characteristics are investigated. The component is constructed with two graded-index (GRIN) rod lenses for matching different parameters between bunched and mono-core optical fibers. The method of analyzing mismatching and misalignment losses is based on geometrical optics. Measured losses are found to be in agreement with the calculated results and demonstrate that bunched optical fibers can be branched with low loss. Crosstalk measurements show that crosstalk attenuation greater than 30 dB can be easily maintained in the component.

To produce an ultra-high fiber count optical cable with ultra-high density for subscriber loop applications, a new multicore fiber format, called "flat bunch fiber" format has been developed and manufactured. Individual cores in a flat bunch fiber format were arranged in a line contacted with neighboring claddings. This new format gave some advantages over existing optical fibers, from high density and mass-spliceability viewpoints. In this paper, fundamental characteristics of a flat bunch fiber, such as optical loss, bending, microbending, and tensile strength were mainly studied experimentally, comparing with an existing fiber. As a result, good characteristics to use in practice were shown. Moreover, crosstalk, which was one item of great concern for this kind of optical fiber, was the order to -40 dB for 500-m long optical fiber.

Structural modification of poly(p-phenylene sulphide) (PPS) upon heavy doping with SO3 has been investigated by means of 1H n.m.r., 13C CP/MAS n.m.r. and i.r. spectroscopy. It was confirmed that two of the four hydrogens in a unit of the phenyl ring are removed, which excludes the possibility of sulphonation. A direct intramolecular crosslink between neighbouring phenyl rings is shown to be the most probable modification. This forms a poly(benzothiophene) (PBT) molecule, consistent with the conductivity mechanism involving polarons. It is also pointed out that additional crosslinks via sulphuryl groups restrict the conjugation length, thus limiting the enhancement of conductivity.

オープンロールを使用してSBRの素練りを行なったところ, SBRの平均分子量Mは薄通しによる素練り回数Nと次のような近似的関係にあり,M=(M0-M∞)e-αN+M∞Mは素練り条件やポリマーの種類によって決まる一定値 M∞ に収歛することがわかった.次に各素練り状態の異なった試料をムーニー試験機によってテストしたところ, えられたデータは本文中の式(2), (3)および(4)によってその時間的変化が記述されることがわかり, その分子量依存性も近似的に本文中の式(5), (6), (7), (8)および(9)によって記述できることがわかった. これは未素練り SBR における分子量依存性と全く同じ関係になっているので, SBR の素練り過程はその平均分子量を知ることによってすべて明らかにされることがわかった.

レラクソメーターにより分子量が2.0×105～6.0×105の範囲にわたる4種のSBRおよびPB (ポリブタジエン) 試料について, 測定温度が25～150°Cの範囲でゴム状領域における応力緩和実験を行った. えられた結果を時間温度換算則および線型粘弾性現象論によって整理し, 合成緩和曲線, shift factor #aT, 緩和スペクトル, 定常流動粘度などを求めた. その結果, 未加硫SBRおよびPBもまた, 他の無定形高分子と本質的に同じような線型粘弾性挙動を示すものであるということがわかった.

スペクトロメータおよびトーションペンデュラムにより2種のSBRおよびIR (ポリイソプレン) 試料について, 周波数が0.2～70C.P.S.および測定温度範囲が-80℃～+90℃で遷移領域における動的測定をおこなった.その結果, SBRおよびIRの未加硫物もまた他の無定形高分子と本質的に同じ線型粘弾性挙動を示すものであることがわかった.

In a previous paper, the relationship between the relaxation spectrum of an amorphous high polymer in the rubbery region and the molecular weight distribution function was studied by the phenomenological theory method. We found a simple, direct proportional relationship between them. The reliability of assumptions and approximations made for the theoretical study can be evaluated by comparison of calculated and experimental data. As reported previously, selection of values for the simplified method was optional in calculating molecular weight dependence of the relaxation spectrum of a sample with a homogeneous distribution. Therefore, the feasibility of selection has to be evaluated by comparison of calculated results with observed data. For the comparison, it is necessary to obtain experimental data for a sample having a homogeneous distribution and compare it with calculated results for the relaxation spectrum and molecular weight distribution of the previous paper. However, these data are scarce in the current literature. From available past literature, we selected polystyrene, poly(vinyl acetate) and polyisobutene as typical samples of amorphous high polymers. In addition, experimental data for two samples of polystyrene were included. Thus, data for a total of five samples were compared with calculated results of the previous paper.

分子状には混合していないが巨視的には混合しているような高分子系のなかで, 例えば, ゴム～充てん剤系, 無定形高分子～微結晶系あるいは一部のポリマーブレンド系などのように, 非連続相成分が連続相成分にくらべて著しく変形しにくいような混合系についてその力学的性質に関する混合法則を求めることを理論的に試みた.先ず非連続相成分である分散粒子と連続相成分であるゴム状ポリマーとの界面における相互作用を, 分散粒子径のみかけ上の増大および連続相における自由容積の減少という2つの効果によって近似的に表現し, 次に巨視的には両相の変形量の和が混合系の変形量に等しくなるとして, 結局複素コンンプライアンス, J*(ω), について次のような混合法則がえられることを示した.J*bl (ω) =φ1J*1 (λ1ω) +φ2J*2 (λ2ω) ここに添字bl, 1および2はそれぞれ混合系, 非連続相成分および連続相成分をあらわし, φおよびλは両相問の相互作用や両相の混合比などによって変化するパラメターである.上述のような混合系では上式右辺第1項の寄与は第2項のそれにくらべて無視できるから, φ2およびλ2の値は実験的に簡単に求めることができる.また, 分散粒子径のみかけ上の増大は非連続相成分のみかけ上の容積分率, νe, が(φ2/λ2)= [1- (νe/0.74)] 2.5によって与えられることから定量的に評価することができる.既発表の代表的な実験例に対してこの混合法則を適用してみたところ, かなり高精度で一般的な適合性をもつものと期待される結果がえられた.

活性および不活性充てん剤と代表的な2, 3のゴムとを組み合わせ, 充てん剤濃度を変えて得た20数個の試料について破断および応力緩和実験を行ない, 従来の知見を基にして得た方法により解析した. その結果, i) 破断スペクトルの形状は充てん剤の混入によってほとんど影響を受けず純ゴムの場合の形状的特徴を維持する. ii) 純ゴムの場合と同じ方法でかつ同程度の近似で数式表示がき, 式中のパラメータの値も充てん剤混合系として特異な値をとることはなかった. iii) 破断伸びが最大になる温度Tmaxは充てん剤とともに大きくなり, 同程度の加硫状態では活性充てん剤混合系のTmax>純ゴムのTmax>不活性充てん剤混合系のTmaxの傾向がある, iv) 最大破断伸長比αbmaxに対しては内部変形に関する一体近似を含む混合則がかなりよく適用できる, などのことがわかった.

ゴム状ポリマーの線形粘弾性挙動におよぼす同族列の混合効果に関する最近の研究結果をもとにして, 緩和スペクトルと分子量分布関数との関係の定量化を現象論的方法によって試みた.その結果, まずゴム状領域の緩和スペクトル, H(lnθ)は分子量の重量 (微分) 分布関数, f(M)と次のような関係にあることがわかった.H(lnθ)=∫0∞f(M)HM(ln[θ/λM])dM.HMは均一分配試料の緩和スペクトル, λMは均一分配試料が他の異分子量試料と混合する際におこる摩擦抵抗の変化に関係するパラメータであってともに分子量, Mの関数である.HMおよびλMの分子量依存性を既発表の実験結果から類推し, さらに適当な近似によって次のような関係式を導いた.H(lnθM)/G0=Mnf(M)/3.4,G0θM/K=M3.4.ここにMnは試料の数平均分子量であり, G0およびKはそれぞれrubbery plateauの剛性率および定常流粘度についての3.4乗則の比例定数であっていずれも分子量には依存しない.