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This paper considers an output-based event-triggered control approach for discrete-time systems and proposes three new types of performance measures under unknown disturbances. These measures are motivated by the fact that signals in practical systems are often associated with bounded energy or bounded magnitude, and they should be described in the $ \ell_{2} $ and $ \ell_\infty $ spaces, respectively. More precisely, three performance measures from $ \ell_{q} $ to $ \ell_{p} $, denoted by the $ \ell_{p/q} $ performances with $ (p, q) = (2, 2), \ (\infty, 2) $ and $ (\infty, \infty) $, are considered for event-triggered systems (ETSs) in which the corresponding event-trigger mechanism is defined as a function from the measured output of the plant to the input of the dynamic output-feedback controller with the triggering parameter $ \sigma (>0) $. Such a selection of the pair $ (p, q) $ represents the $ \ell_{p/q} $ performances to be bounded and well-defined, and the three measures are natural extensions of those in the conventional feedback control, such as the $ H_\infty $, generalized $ H_2 $ and $ \ell_1 $ norms. We first derive the corresponding closed-form representation with respect to the relevant ETSs in terms of a piecewise linear difference equation. The asymptotic stability condition for the ETSs is then derived through the linear matrix inequality approach by developing an adequate piecewise quadratic Lyapunov function. This stability criterion is further extended to compute the $ \ell_{p/q} $ performances. Finally, a numerical example is given to verify the effectiveness of the overall arguments in both the theoretical and practical aspects, especially for the trade-off relation between the communication costs and $ \ell_{p/q} $ performances.

This paper considers a model-free control approach to Euler-Lagrange equations and proposes a new quantitative performance measure with its Lyapunov-based computation method. More precisely, this paper aims to solve a trajectory tracking problem for uncertain Euler-Lagrange equations by using a model-free controller with a proportional-integral-derivative (PID) control form. The $ L_\infty $-gain is evaluated for the closed-loop systems obtained through the feedback connection between the Euler-Lagrange equation and the model-free controller. To this end, the input-to-state stability (ISS) for the closed-loop systems is first established by deriving an appropriate Lyapunov function. The study further extends these arguments to develop a computational approach to determine the $ L_\infty $-gain. Finally, the theoretical validity and effectiveness of the proposed quantitative performance measure are demonstrated through a simulation of a $ 2 $-degree-of-freedom ($ 2 $-DOF) robot manipulator, which is one of the most representative examples of Euler-Lagrange equations.

The purpose of this study was to evaluate the factors associated with the bioimpedance phase angle (PhA) in older patients with prostate cancer, and to determine the optimal cutoff for the PhA in patients with sarcopenia and prostate cancer.This retrospective cross-sectional analysis enrolled patients with prostate cancer aged ≥60 years. Appendicular skeletal muscle mass and PhA estimated by bioimpedance analysis, grip strength, the five-time chair stand test, gait speed, the Short Physical Performance Battery, the 2-min walk test and the International Physical Activity Questionnaire Short Form were obtained at enrollment. The diagnosis of sarcopenia was based on the 2019 consensus of the Asian Working Group for Sarcopenia.In total, 119 male participants (mean age = 70.7 ± 6.1 years) were available for analysis. A multivariable linear regression model revealed that age, body mass index and the maximal grip strength value were associated with the PhA. The area under the receiver operating characteristic curve value of the PhA for sarcopenia diagnosis was 0.77 (95% confidence interval 0.64-0.90, P 0.001), with a PhA cutoff value of 4.87°.PhA estimated by bioimpedance analysis may be utilized as useful clinical biomarker for reflecting muscle strength and sarcopenia in older patients with prostate cancer. Geriatr Gerontol Int 2022; 22: 623-627.

Objective : The percutaneous thread transection technique is a surgical dissecting method using a dissecting thread inserted through a needle under ultrasound guidance without skin incision. As the new dissecting threads were developed domestically, this cadaver study was conducted to compare the effectiveness and safety between the new threads (ultra V sswire and smartwire-01) and a pre-existing commercial dissecting thread (loop & shear) by demonstrating a modified looped thread cubital tunnel release.Methods : The percutaneous cubital tunnel release procedure was performed on 29 fresh cadaveric upper extremities. The preexisting commercial thread was used in 5 upper extremities. The two newly developed threads were used in 24 upper extremities. Two practitioners performed the procedures separately. After the modified looped thread cubital release, anatomical and histological analyses were performed by a blinded anatomist. The presence of the dissected cubital tunnel and damaged adjacent soft tissue was assessed.Results : Out of the 29 cadaveric upper extremities, 27 specimens showed complete dissection of the Osborne ligament and the proximal fascia of the flexor carpi ulnaris muscle. One specimen was incompletely dissected in each of the ultra V sswire and smartwire-01 groups. There were no injuries of adjacent structures including the ulnar nerve, ulnar artery, medial antebrachial cutaneous nerve, or flexor tendon with either the commercial thread or the newly developed threads. The anatomical analysis revealed clear and sharp incisional margins of the cubital tunnel in the Smartwire-01 and loop & shear groups. All three kinds of threads maintained proper linear elasticity for easy handling during the procedure. The smartwire-01 provided higher visibility in ultrasound than the other threads.Conclusion : The newly developed threads were effective and safe for use in the thread cubital tunnel release procedure.

Background Reconstruction of congenital microtia remains challenging, particularly in patients with a history of ear canaloplasty due to insufficient regional soft tissue. The insertion of a tissue expander prior to implantation of the cartilage framework has traditionally been employed. However, this procedure could induce additional morbidity. Herein, we present a method using V-Y advancement of a temporal triangular flap to gain additional soft tissue in these challenging cases. Methods Congenital microtia patients with a history of ear canaloplasty who underwent auricular reconstruction using the Nagata technique between 2016 and 2020 were reviewed. To obtain additional soft tissue, V-Y advancement of a temporal triangular flap was performed concurrently with implantation of the costal cartilage framework, without prior insertion of a tissue expander. The outcomes of these patients with respect to postoperative complications and esthetics were evaluated. Results Eight patients with bilateral lesions were included. No specific complications developed after the first-stage surgery. However, one patient experienced complications after the second stage (auricular elevation). An analysis of the esthetic results showed most patients had excellent outcomes, achieving a satisfactory convolution. The median number of operations needed to complete reconstruction was 2, which was fewer than required using the conventional method with prior insertion of a tissue expander. Conclusions In patients with a history of previous canaloplasty, V-Y advancement of a temporal triangular flap could serve as an alternative to tissue expansion for microtia reconstruction. This technique provided reliable and satisfactory results with a reduced number of surgical stages.

Background This study aimed to assess whether the reconstructed breast volume changed postoperatively following a deep inferior epigastric artery perforator (DIEP) flap. Methods Patients were included if they had undergone unilateral breast reconstruction with a DIEP flap at the two selected centers between April 2017 and September 2019. Serial 3-D surface imaging of both breasts was taken at 1, 3, 6, and 12 months postoperatively. The primary outcome was a volume ratio of the reconstructed to the contralateral breast. A linear mixed-effect model was used to evaluate whether the DIEP flap volume changed according to the postoperative time. Results A total of 74 patients were included in the analysis. The mean volume ratio of the reconstructed side compared with the contralateral breast at 1, 3, 6, and 12 months postoperatively were 106.9%, 105.9%, 108.7%, and 107.6%, respectively. In the linear mixed effect model, the volume ratio of the reconstructed breast did not change over time for immediate reconstructions (p = 0.376). However, there was an increase over time in delayed reconstructions (p = 0.043). Adjuvant radiation, chemotherapy, and hormone therapy did not influence the volume ratio of the reconstruced breast. Correlation analysis using repeatedly measured values showed that both reconstruced and healthy breast volumes had positive correlation with the patient's body weight (p Conclusion The volume ratio of the reconstructed to the contralateral breast does not decrease postoperatively following DIEP flap breast reconstruction.

Background Experimental studies have reported that angiotensin receptor blockers (ARBs) increase the risk of surgical complications. However, clinical data on their effect on surgical outcomes are limited. The aim of this study was to investigate the impact of perioperative use of ARBs on the outcomes of breast reconstruction using population-based claim data. Methods Data of patients who underwent direct-to-implant or abdomen-based autologous breast reconstruction after total mastectomy from April 2015 to December 2018 were obtained from the Health Insurance Review and Assessment Service database. The patients were categorized as ARB, non-ARB, control, and non-hypertension groups. The effects of ARBs on surgical complications, length of hospital stay, and complication-related medical costs were evaluated. Results Of the 9,036 patients who met the inclusion criteria, 5,192 underwent direct-to-implant reconstruction, and 3,844 underwent abdomen-based autologous reconstruction. The length of hospital stay was the longest and the surgical complication rate and complication-related medical cost were the highest in the ARB group after both reconstruction methods. Compared with non-treatment with antihypertensive drugs, ARB use was found to be an independent risk factor for surgical complications in direct-to-implant reconstruction [odds ratio (OR), 1.96; 95% confidence interval (CI), 1.09-3.50; P=0.0237] and complication-related medical cost (OR, 1.93; 95% CI, 1.10-3.40; P=0.0221) in abdomen-based autologous reconstruction. Conclusions Perioperative ARB use was associated with adverse postoperative breast reconstruction outcomes. These findings might have a significant impact on perioperative antihypertensive management; nevertheless, further studies are warranted to confirm the study findings.

Background In two-stage prosthetic breast reconstruction, two types of tissue expanders are used for the first stage: microtextured Siltex and macrotextured Biocell. Despite emerging concerns regarding the safety of macrotextured prostheses, the association between the use of macrotextured expanders and adverse outcomes remains unknown clinically. This study aimed to evaluate potential impacts of the type of tissue expander on the long-term outcomes of implant-based breast reconstruction. Methods Patients who underwent immediate two-stage tissue expander/implant breast reconstruction between 2014 and 2018 were evaluated and categorized into two groups according to the expander type. Those two were propensity score matched for baseline characteristics and compared for complication rates after the first- and second-stage operations. The impacts of several variables, including type of tissue expander used, on outcomes were assessed using multivariable logistic regression analyses. Results Of the 1391 cases in 1294 patients, 276 pairs (552 cases) were successfully propensity score matched. In the first-stage operation, the macrotextured group showed a significantly shorter drain indwelling period and lower rate of seroma than the microtextured group. These differences retained influences after adjusting for other variables. Incidence rates of other complications were similar between the groups. Regarding the second-stage operation, the use of macrotextured expanders showed a significant association, with an increased rate of severe capsular contracture on the multivariable analyses in cases using textured implants. Development of other complications was not affected by the expander type. Conclusion The type of tissue expander might influence the outcomes of two-stage implant-based breast reconstruction, and generally acceptable safety of both microtextured and macrotextured expanders was shown. Clinical question/level of evidence Therapeutic, III.

Transcranial direct current stimulation (tDCS) is one of the latest post-stroke dysphagia treatment modalities, and the effect of tDCS is known to be affected by various factors including genetic polymorphisms. However, the role of catechol-O-methyltransferase (COMT) polymorphisms on tDCS in swallowing is unclear. In this prospective pilot study, we aim to explore the effect of tDCS on the swallowing cortex and subsequent swallowing motor function according to COMT polymorphism. Twenty-four healthy participants received either anodal tDCS or sham mode tDCS on the mylohyoid motor cortex at random order, after inhibitory repetitive transcranial magnetic stimulation (rTMS) for preconditioning. The primary outcome was the changes of mylohyoid-motor-evoked potentials (MH-MEP) amplitude in each COMT polymorphism group, from the post-inhibitory rTMS baseline state to immediate, 30, and 60 min after tDCS. The secondary outcomes were the changes in swallowing function. The results showed that COMT Val/Val polymorphism showed improvement across time in the MH-MEP amplitudes and triggering time of swallowing after tDCS, whereas COMT Met carrier group did not show significant changes of MH-MEP or swallowing function across time. This therapeutic response variability of tDCS in the mylohyoid motor system according to COMT polymorphism support the importance of genetic analysis in individualized dysphagia treatment.

Background After receiving breast cancer surgery or reconstruction, shoulder dysfunctions including weakness, post-operative pain, shoulder joint instability, and limited range of motion (ROM) often occur. Due to limited ROM, patients may suffer difficulty in activities of daily living, and quality of life may be reduced. The objective of this study is to compare the effects on shoulder ROM of a real-time interactive digital healthcare system and brochure-based home rehabilitation program in post-operative breast cancer patients. Methods This study is a prospective, multi-center, assessor-blinded randomized controlled trial. The study aims to recruit 100 breast cancer patients exhibiting limited shoulder ROM after undergoing axillary lymph node dissection or breast reconstruction following mastectomy. Patients will be randomly assigned to two groups for 8 weeks of rehabilitation: a digital healthcare system rehabilitation (intervention) group and a brochure-based rehabilitation (control) group. The primary outcome is the change in ROM of the affected shoulder between baseline and 12 weeks after enrollment. Secondary outcomes include pain in the affected shoulder, as measured using a numerical rating scale, functional outcomes (QuickDASH scores), and quality of life (FACT-B and EQ-5D-5L scores), all of which will be measured on enrollment and 4, 8, and 12 weeks thereafter. Discussion This study will compare the effectiveness of a newly developed, augmented reality-based real-time interactive digital healthcare system with that of brochure-based home rehabilitation for improving the shoulder ROM, pain, functional outcomes, and quality of life of post-operative breast cancer patients. Trial registration ClinicalTrials.govNCT04316156. Registered on 20 March 2020.

Motivated by the fact that a number of present state estimations require some presumed conditions and could not lead to a desired accuracy when they are applied to real systems, this paper is concerned with providing a new framework for the state estimation. We first introduce some existing methods of state estimations and describe their weaknesses for unknown bounded persistent elements. Aiming at taking into account more practical situations of real systems, which cannot be treated by the existing methods, this paper provides a new state estimation method by using the l1 optimal control theory. More precisely, the new state estimation method called the l 1 optimal state estimation considers unknown bounded persistent elements such as external disturbances and measurement noises, which often occur in the systems and make the estimation difficult. The problem of minimizing the effect of the bounded persistent elements on the corresponding state estimation error could be mathematically formulated by using the arguments on l 1 optimal state estimation introduced in this paper. Finally, the effectiveness of the l 1 optimal state estimation is demonstrated through some simulation results associated with the center of mass (CoM) estimation for a bipedal robot on its linear inverted pendulum model (LIPM).

As visual perception development proceeds rapidly after birth, early detection of developmental maturity is required. Healthy infants do not have many opportunities for visual perception evaluation, so a reliable evaluation method is necessary. This retrospective study included 276 healthy full-term infants p < 0.05). In those 12 month and above, no clinical factors were significantly associated with the PreViAs scores in all domains. The PreViAs questionnaire is a useful tool for visual assessment of healthy full-term infants under 24 months of age, suggesting reference values and cutoff scores according to age, and estimating the maturation age for visual perception development of each domain.

A stroke may be followed by central post-stroke pain (CPSP), which is characterized by chronic neuropathic pain. The exact mechanism has not yet been fully uncovered. We investigated alterations in the white matters in patients with CPSP, compared with stroke patients without CPSP and normal controls. Our retrospective cross-sectional, case-control study participants were assigned to three groups: CPSP (stroke patients with CPSP (n = 17)), stroke control (stroke patients without CPSP (n = 26)), and normal control (normal subjects (n = 34)). The investigation of white matter for CPSP was focused on the values of fiber numbers (FN) and fractional anisotrophy (FA) for spinothalamic tract (STT), anterior thalamic radiation (ATR), superior thalamic radiation (STR) and posterior thalamic radiation (PTR), and corticospinal tract (CST) was measured. The FA for the STT and STR of the CPSP group were lower than those for the stroke control and normal control groups. The FA of CST and ATR did not differ between the CPSP and stroke groups, but both differed from the normal control. The FA of PTR in the stroke control group differed from the normal control group, but not from the CPSP group. The FN of CST, STT, ATR, and STR for the CPSP and stroke control groups did not differ from each other, but both differed from those of normal controls. FN of PTR did not differ between the CPSP and normal control groups. The alterations in the spinothalamic tract and superior thalamic radiation after stroke would play a role in the pathogenesis of CPSP.

Background and objectives: This study aimed to determine the cut-off values of the following three respiratory pressure meters, the voluntary peak cough flow (PCF), maximal expiratory pressure (MEP) and maximal inspiratory pressure (MIP), associated with post-stroke dysphagia and assess which of these parameters show good diagnostic properties associated with post-stroke dysphagia. Materials and Methods: Retrospective analysis of a prospectively maintained database. Records of patients with first-ever diagnosed dysphagia attributable to cerebrovascular disease, who had performed spirometry measurements for the PCF, MIP and MEP. Results: From a total of 237 stroke patients, 163 patients were diagnosed with dysphagia. Those with dysphagia had significantly lower PCF values than those without dysphagia (116.3 &plusmn, 75.3 vs. 219.4 &plusmn, 91.8 L/min, p &lt, 0.001). In addition, the former group also had lower MIP (30.5 &plusmn, 24.7 vs. 41.6 &plusmn, 25.7 cmH2O, p = 0.0002) and MEP (41.0 &plusmn, 27.9 vs. 62.8 &plusmn, 32.3 cmH2O, p &lt, 0.001) values than the latter group. The receiver operating characteristic curve analysis showed that the PCF cut-off value of 151 L/min (area under the receiver operating characteristic curve [AUC] 0.81, sensitivity 72%, specificity 78.8%) was associated with post-stroke dysphagia. The optimum MEP and MIP cut-off were 38 cmH2O (AUC 0.70, sensitivity 58%, specificity 77.7%) and 20 cmH2O (AUC 0.65, sensitivity 49%, specificity 84%). PCF showed the highest AUC results. Results from the univariate analysis indicated that PCF values of &le, 151 L/min increased risk of dysphagia by 9.51-fold (4.96&ndash, 18.23). Multivariable analysis showed that after controlling of other clinical factor, the PCFs at this cut-off value still showed increased risk of by 4.19 (2.02&ndash, 83.69) but this was not observed with the MIPs or MEPs. Conclusions: Our study has provided cut-off values that are associated with increased risk of dysphagia. Among the three parameters, PCF showed increased association with post-stroke dysphagia.

Background: Resorption of the cartilage framework results from hematoma or infection, deteriorating outcomes in microtia reconstruction. Delayed resorption still occurs for unclear reasons in patie...

Background Previous studies suggest that specific genes may predispose some to increased risk of dysphagia in the geriatric population, but whether these genes may affect swallowing recovery after a stroke is unknown. This study investigated whether single-nucleotide polymorphisms (SNP) of the brain-derived neurotrophic factor (BDNF), catechol-O-methyl transferase, apolipoprotein E, interleukin-1 receptor antagonist, and dopamine, which have been linked to swallowing, could adversely affect the prognosis of post-stroke dysphagia. Methods In this study, 218 subjects with confirmed post-stroke dysphagia were enrolled. The primary endpoint was failed recovery from nil per mouth (NPM) status with the first 3 months post-stroke. Key results The Val/Val group from the rs6265, BDNF, showed higher score changes on the Functional Oral Intake Scale at 1 month. The proportion of patients with recovery from NPM status within the first 1 month was 60.8% in the Val/Val group, which was statistically higher than those in the Met allele groups (38.1%, P = .017). At 3 months, the BDNF rs6265 showed significant group differences in Modified Barium Swallow Impairment Profile© score changes with the Val/Val allele leading to greater improvement. However, no single SNP was associated with increased risk of poor recovery with persistence of NPM at 3 months post-stroke. Conclusions and inferences Those with the dominant Val/Val phenotype of BDNF manifested with faster and greater improvement than the Met-phenotypes. Based on our results, the BDNF Val allele may play a positive role with faster score improvement and rapid recovery from NPM than the Met allele. Clinical Trials gov: NCT03577444 (https://clinicaltrials.gov/ct2/show/study/NCT03577444).

Stroke often leads to disability, and poststroke survivors often have limited accessibility to medical facilities.For such patients, mobile videoconferencing technology offers an opportunity to perform follow-up assessment and appropriate management of cognitive impairment. We aimed to determine the validity of the Korean version of the Mini-Mental State Examination (MMSE-K) when administered using a smartphone.Thirty patients with ischemic or hemorrhagic stroke were included in this study (20 males, 10 females; mean age, 69.8 ± 12.9 years). Both face-to-face and remote assessments of cognitive function through MMSE-K were performed for each patient at an interval of at least 3 days. Additionally, an in-person collaborator evaluated the MMSE-K score during the remote assessment. A smartphone and a tablet were used by the patient and the examiner, respectively, and remote connection was mediated using a dedicated videoconferencing application. The MMSE-K scores obtained through face-to-face, remote, and in-person assessments were compared using the Wilcoxon signed rank test and the Spearman correlation analysis.There was good agreement between face-to-face and remote assessments, as well as between remote assessment and in-person collaborator's evaluation regarding total MMSE-K score and subscores for each MMSE-K domain (orientation, memory, attention/calculation, language, and visuospatial function).Remote assessment can be a useful clinical evaluation method, and this study confirmed the validity.The smartphone represents a promising tool for the assessment of cognitive function in clinical practice, but further research into the intra- and inter-rater reliability of observations is warranted.