Tract seeding in indwelling pleural catheter placement for the drainage of malignant pleural effusions: Incidence and related clinical and imaging factors.

BACKGROUND: The incidence of tract seeding after the placement of indwelling pleural catheter (IPC) for malignant pleural effusion drainage has been variable in the literature. RESEARCH QUESTION: To evaluate the incidence of IPC-related cancer tract seeding and find out related demographic, clinical or imaging factors to the tract seeding. STUDY DESIGN AND METHODS: This retrospective study included 124 consecutive patients seen between January 2011 and December 2021 who underwent IPC placement for malignant pleural effusion drainage. Chest radiographs before IPC placement and serial chest CT studies were obtained. One patient was diagnosed pathologically, and the other patients were diagnosed as tract seeding radiologically. The incidence of and related factors to tract seeding were assessed by reviewing medical records and imaging studies. RESULTS: The incidence of IPC tract seeding was 21.7% (27 of 124 malignant effusions). Of 27 patients, 15 had primary lung cancer and remaining 12 had extra-thoracic malignancy. Adenocarcinoma (19 of 27, 70.3%) either from the lung (N = 12) or extra-thoracic malignancy (N = 7) was the most common cell type. Mean time elapsed until tract seeding occurrence after IPC placement was 96 days (ranges; 28-306 days). The survival in seeding group after IPC placement was 185 days (ranges, 32-457 days). On odd ratio analysis, the presence of mediastinal pleural thickening (OR [95% CI]; 9.79 (2.67-35.84), p = 0.001) was significantly related to the occurrence of tract seeding. Neither tumor volume within pleural space (p = 0.168), duration of IPC indwelling (p = 0.142), days of survival after IPC placement (p = 0.26), nor pleural effusion amount (p = 0.481) was related to the tract seeding. INTERPRETATION: IPC tract seeding is seen in 27 (21.7%) of 124 malignant pleural effusion patients, particularly with adenocarcinoma cytology. CT features of mediastinal pleural thickening are related to the occurrence of tract seeding.

Development of a Real-Time Pixel Array-Type Detector for Ultrahigh Dose-Rate Beams.

Although research into ultrahigh dose-rate (UHDR) radiation therapy is ongoing, there is a significant lack of experimental measurements for two-dimensional (2D) dose-rate distributions. Additionally, conventional pixel-type detectors result in significant beam loss. In this study, we developed a pixel array-type detector with adjustable gaps and a data acquisition system to evaluate its effectiveness in measuring UHDR proton beams in real time. We measured a UHDR beam at the Korea Institute of Radiological and Medical Sciences using an MC-50 cyclotron, which produced a 45-MeV energy beam with a current range of 10-70 nA, to confirm the UHDR beam conditions. To minimize beam loss during measurement, we adjusted the gap and high voltage on the detector and determined the collection efficiency of the developed detector through Monte Carlo simulation and experimental measurements of the 2D dose-rate distribution. We also verified the accuracy of the real-time position measurement using the developed detector with a 226.29-MeV PBS beam at the National Cancer Center of the Republic of Korea. Our results indicate that, for a current of 70 nA with an energy beam of 45 MeV generated using the MC-50 cyclotron, the dose rate exceeded 300 Gy/s at the center of the beam, indicating UHDR conditions. Simulation and experimental measurements show that fixing the gap at 2 mm and the high voltage at 1000 V resulted in a less than 1% loss of collection efficiency when measuring UHDR beams. Furthermore, we achieved real-time measurements of the beam position with an accuracy of within 2% at five reference points. In conclusion, our study developed a beam monitoring system that can measure UHDR proton beams and confirmed the accuracy of the beam position and profile through real-time data transmission.

Impact of radiation on immune cells in patients with low-grade brain tumor: Identifying critical factors affecting lymphopenia and neutrophil-to-lymphocyte ratio.

PURPOSE: Studies about the effect of radiation therapy (RT) on immune cells are usually limited to a high-grade glioma mostly exposed to chemotherapy and a high dose of steroid which also could affect immune cells. The purpose of this retrospective analysis of low-grade brain tumor patients treated by RT alone is to determine significant factors influencing neutrophil-to-lymphocyte ratio (NLR), absolute neutrophil counts (ANC), and absolute lymphocyte counts (ALC). MATERIALS AND METHODS: A total of 41 patients who received RT between 2007 and 2020 were analyzed. Patients who received chemotherapy and high-dose of steroid were excluded. ANC and ALC were collected before starting RT (baseline) and within one-week before ending RT (post-treatment). Changes of ANC, ALC, and NLR between baseline and post-treatment were calculated. RESULTS: ALC decreased in 32 patients (78.1%). NLR increased in 31 patients (75.6%). No patients developed grade 2 or higher hematologic toxicities. The decrease of ALC was significantly correlated with the dose to brain V15 in a simple and multiple linear regression (p = 0.043). Brain V10 and V20 adjacent to V15 were also marginally significant factors determining the reduction of lymphocytes (p = 0.050 and p = 0.059, respectively). However, it was difficult to find predictive factors affecting changes of ANC and NLR. CONCLUSION: In low-grade brain tumor patients who are treated by RT alone, ALC decreased and NLR increased in three-fourth of patients, although the magnitude was minimal. The decrease of ALC was mainly affected by low dose to the brain. However, RT dose was not correlated with changes of ANC or NLR.

Substantiating the Therapeutic Effects of Simultaneous Heat Massage Combined with Conventional Physical Therapy for Treatment of Lower Back Pain: A Randomized Controlled Feasibility Trial.

BACKGROUND: There are various therapeutic options for the conservative management of lower back pain (LBP). A combination of two or more treatment options may be more effective in the clinical management of non-specific LBP. In this study, we compared the effects of simultaneous heat massage with conventional physical therapy in patients with subacute LBP. METHODS: A single-center randomized controlled trial in which 40 participants with LBP were allocated to one of two groups: a heat massage group (HMG) and physical therapy group (PTG). The HMG received simultaneous heat massage therapy using a mechanical device (CGM MB-1401, Ceragem, Republic of Korea). The PTG received conventional physical therapy. Both groups received 40 min of therapy once daily, five times a week, for a total of four weeks. Changes in serum cortisol, epinephrine (EP), and norepinephrine (NE) were assessed. The outcomes were measured using the pain numeric rating scale (PNRS), the Oswestry disability index (ODI), the Roland-Morris disability questionnaire (RMDQ), the short-form McGill pain questionnaire (SF-MPQ), the multidimensional fatigue inventory (MFI-20), the Beck depression inventory (BDI), surface EMG (sEMG), and sympathetic skin response (SSR) at baseline (PRE), at 2 (2 W) and 4 weeks (4 W) following the intervention. RESULTS: The serum EP and NE levels in the HMG decreased after treatment. The PNRS, ODI, RMDQ, and SF-MPQ scores improved without significance in both groups. The BDI score showed improvement in the HMG before the PTG. The MFI-20 score improved in both groups, but the results were better in the HMG than in the PTG at 4 W. All the activities of sEMG were significantly decreased in both groups. However, the improvement of the %MVIC in the HMG was better than that in the PTG at 4 W. The SSR latency on sEMG decreased while the amplitude increased in the HMG at 2 W and 4 W, respectively. CONCLUSIONS: Following 4 weeks of combined therapies, heat massage was not superior to conventional physical therapy alone. Both treatments were shown to be effective in improving LBP and pain-related disability. However, heat massage was shown to have a better effect on the control of autonomic nerve function and underlying moods.

One-Week versus Two-Week Chemoradiotherapy Followed by Curative Surgery in Rectal Cancer: Long-Term Comparative Pooled Analysis of Two Prospective Multicenter Phase II Trials.

PURPOSE: The optimal short-course chemotherapeutic regimen for rectal cancer has not been clearly defined until now. KROG 10-01 and KROG 11-02 prospective trials investigated the efficacy and safety of 1- and 2-week chemoradiotherapy (CRT), respectively. Materials and Methods: Patients eligible for KROG 10-01 and KROG 11-02 involved those with clinical T3-4N0-2M0 rectal cancers. They received preoperative CRT and total mesorectal excision. Patients in KROG 10-01 received radiation of 25 Gy in 5 fractions during 1 week with 5-fluorouracil/leucovorin. Patients in KROG 11-02 received radiation of 33 Gy in 10 fractions for 2 weeks with oral capecitabine. RESULTS: A total of 150 patients consisting of 70 patients from KROG 10-01 and 80 patients from KROG 11-02 were collectively analyzed. With a median follow-up time of 89.2 months, the 5-year overall survival rate was 86.5% in 1-week CRT and 85.3% in 2-week CRT (p=0.841). The 5-year recurrence-free survival rate was 83.5% in 1-week CRT and 77.1% in 2-week CRT (p=0.448). One patient (1.4%) in 1-week CRT and 11 patients (13.8%) in 2-week CRT exhibited pathologic complete regression (ypT0N0M0) after radiotherapy (p=0.006). One-week CRT had significantly higher acute hematologic (12.8% vs. 3.8%, p=0.040) and nonhematologic (38.6% vs. 16.3%, p=0.002) toxicity than 2-week CRT. CONCLUSION: Both 1- and 2-week schedules of CRT showed favorable survival outcomes after 7 years of follow-up. But, 2-week course achieved more increased tumor response and decreased acute toxicity than 1-week course.

Heterologous Expression and Purification of a CRISPR-Cas9-Based Adenine Base Editor.

CRISPR-cas9-guided adenine base editors (ABEs) site-specifically convert the A-T base pair to G-C base pair in genomic DNA. The intracellular delivery of ABE proteins preassembled with guide RNAs (gRNAs) has shown greatly reduced off-target effects compared with that of plasmids or viral vectors containing ABE and gRNA-encoding sequences. For efficient gene editing by the ribonucleoprotein delivery method, the ABE-gRNA complexes need to be prepared in high purity and quantity. Here we describe the expression and purification procedure of ABEmax, one of high-efficiency ABE versions.

Pathologic Implications of Radial Resection Margin and Perineural Invasion to Adjuvant Chemotherapy after Preoperative Chemoradiotherapy and Surgery for Rectal Cancer: A Multi-Institutional and Case-Matched Control Study.

We assessed the exact role of adjuvant chemotherapy after neoadjuvant chemoradiotherapy (CRT) and surgery in rectal cancer patients with positive surgical margin or perineural invasion (PNI). This multi-institutional study included 1799 patients with rectal cancer at cT3-4N0-2M0 stages. Patients were divided into two groups. The high-risk group had a positive margin and/or perineural invasion. The low-risk group showed no positive margin or PNI. Propensity-score matching analysis was performed, and a total of 928 patients, with 464 in each arm, were evaluated. The high-risk group showed significant differences in overall survival (OS, 73.4% vs. 53.9%, p < 0.01) and recurrence-free survival (RFS, 52.7% vs. 40.9%, p = 0.01) at five years between the adjuvant chemotherapy arm and observation arm. The low-risk group showed no significant differences in 5-year OS (p = 0.61) and RFS (p = 0.75) between the two arms. Multivariate analyses showed that age, pathologic N stage, and adjuvant chemotherapy were significantly correlated with OS and RFS in the high-risk group (all p < 0.05). Adjuvant chemotherapy improved OS and RFS more significantly in rectal cancer patients with positive surgical margin or PNI than in those with negative surgical margin and PNI.

Numerical and Experimental Analysis of DVA on the Flexible-Rigid Rail Vehicle Carbody Resonant Vibration.

This paper examines the influence of the equipment considered as a DVA (Dynamic Vibration Absorber) upon the mode of vertical vibrations of the car body in high-speed vehicles. The car body is represented as an Euler-Bernoulli beam to minimize flexible vibration. The DVA approach is used to find the appropriate suspension frequencies for various types of equipment. A vertical mathematical model with a flexible car body and equipment is developed to investigate the effect of equipment mass, suspension stiffness, damping, and mounting location on car-body flexible vibrations. A three-dimensional, rigid-flexible coupled vehicle system dynamics model is developed to simulate the car body and equipment's response to track irregularities. The experimental result was considered to verify the theoretical analysis and dynamic simulation. The mathematical analysis demonstrates that the DVA theory can be used to design the suspension parameters of the equipment and that it is suitable and effective in reducing the flexible vibration of the car body in which the vertical bending mode is greatly affected. Heavy equipment should be mounted as close to the car body's center as possible to achieve significant flexible vibration reduction, whereas light equipment contributes very little flexible vibration reduction.

Synthesis and Characterization of a Conductive Polymer Blend Based on PEDOT:PSS and Its Electromagnetic Applications.

The purpose of this study is to prepare a resistive lossy material using conducting polymers for electromagnetic wave absorbers. This paper presents a conductive paste largely composed of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) with a polyurethane binder. The various secondary compounds are added in small amounts to an aqueous blended solution in order to enhance the electrical and mechanical properties of the conductive thin film. The synthesized conductive paste is characterized through electrical, chemical, and morphological analyses. The electrical conductivity of the thin film is measured using a four-point probe and surface profiler. The chemical and morphological changes are studied in various experiments using a Raman microscope, X-ray photoelectron spectroscopy, a scanning electron microscope, and an atomic force microscope. In order to verify the applicability of the synthesized conductive paste, which is composed of 70 wt% PEDOT:PSS, 30 wt% polyurethane, and secondary additives (DMAE 0.4 wt%, A-187 0.5 wt%, DMSO 7 wt%, Dynol 604 0.1 wt%, PUR 40 2.5 wt%), the Salisbury screen absorber is fabricated and evaluated in the X-band. According to the results, the absorber resonates at 9.7 GHz, the reflection loss is -38.6 dB, and the 90% absorption bandwidth is 3.4 GHz (8.2 to 11.6 GHz). Through this experiment, the applicability of the PEDOT:PSS-based conductive paste is sufficiently verified and it is found that excellent radar-absorbing performance can be realized.

Short- and long-term outcomes of local excision with adjuvant radiotherapy in high-risk T1 rectal cancer patients.

PURPOSE: The standard of care for early rectal cancer is radical surgery; however, it carries high postoperative morbidity. This study aimed to assess the short-term and oncological outcomes of local excision and adjuvant radiotherapy in patients with high-risk pathological stage (p) T1 rectal cancer. METHODS: Fifty-five patients underwent local excision with adjuvant radiotherapy or radical resection for high-risk T1 rectal cancer. Patients with adenocarcinoma within 10 cm from the anal verge; pT1 with high-risk features (grade 3-4); a tumor size of ≥3 cm; a positive margin; a lymphovascular or perineural invasion; or a submucosal invasion depth of ≥SM2 were included. RESULTS: The rates of postoperative complications and stoma formation were higher in the radical surgery group (P = 0.021 and P = 0.003, respectively). No significant differences were observed in the overall survival and disease-free survival (DFS) between the 2 groups (P = 0.301 and P = 0.076, respectively). Vascular invasion was a significantly poor prognostic factor for DFS (P = 0.033). The presence of 3 or more high-risk features was associated with a poor DFS (P = 0.002). CONCLUSION: Local excision with adjuvant radiotherapy significantly reduces the risk of complications and stoma formation. It is also an alternative option for patients with fewer than 3 high-risk features.

Effects of Personal Low-Frequency Stimulation Device on Myalgia: A Randomized Controlled Trial.

Electrotherapy is commonly used for myalgia alleviation. Low-frequency stimulation (LFS) is primarily used for controlling acute and chronic pain and is a non-invasive therapy that can be easily performed with electric stimulation applied on the skin. However, little evidence exists regarding the pain alleviation effects of personal low-frequency stimulation device for home use. Moreover, no studies have compared myalgia alleviation effects between personal low-frequency stimulation (PLS) and physical therapy (PT), which are most commonly used for patients with myalgia in hospitals and clinics. Therefore, we aimed to investigate the pain alleviation effects of PLS in patients with myalgia and compare these effects with those of conventional PT (transcutaneous electrical nerve stimulation + ultrasound). In total, 39 patients with myalgia in the neck, shoulder, back, and waist areas were randomly assigned to the personal low-frequency stimulation group (PLSG: n = 20) and physical therapy group (PTG: n = 19). Both groups were treated for 3 weeks (20 min per session and 5 sessions per week). Patients were assessed for pain intensity by surface electromyography (sEMG), visual analogue scale (VAS) and a short-form McGill pain questionnaire (SF-MPQ) before and after the intervention period. Our results showed that PLSG showed a tendency of muscle relaxation with a significant decrease in sEMG in the neck (p = 0.0425), shoulder (p = 0.0425), and back (p = 0.0046) areas compared to the control group. However, there was no significant difference in waist area. Additionally, VAS scores significantly decreased between pre- and post-treatment in both PTG (p = 0.0098), and PLSG (p = 0.0304) groups, but there was no significance difference between the groups. With respect to SF-MPQ, the PLSG showed greater pain alleviation (5.23 ± 0.25) effects than the PTG (6.23 ± 0.25). Accordingly, our results suggest that PLS treatment using a home device might offer positive assistance in pain alleviation for patients with myalgia that is as equally effective as conventional PT treatment. However, further detailed studies are required considering larger samples to fully claim the effectiveness of this device.

Analysis of PET parameters predicting response to radiotherapy for myeloid sarcoma.

PURPOSE: Positron-emission tomography (PET)-CT has recently been used for diagnostic imaging and radiotherapy for myeloid sarcoma, but there is little research on predicting the response of radiotherapy. The aim of this study was to analyze the association between PET-CT variables and the response to radiotherapy in patients with myeloid sarcoma. MATERIALS AND METHODS: This study was conducted in myeloid sarcoma patients who received radiotherapy and PET-CT before and after radiotherapy. The response to radiotherapy was evaluated based on the European Organization for Research and Treatment of Cancer PET response criteria, and binary regression analysis was performed to assess the factors predicting reductions in the maximum standardized uptake value (SUVmax). RESULTS: Twenty-seven sites in 12 patients were included in the study. Complete metabolic responses were seen in 24 patients after radiotherapy, a partial metabolic response in one, and progressive metabolic disease in two patients. The prescribed dose of more than 3000 cGy10 was significantly greater in the treatment control group (P = 0.024). In binary logistic regression analysis predicting reductions in the SUVmax of more than 70% after radiotherapy, the pretreatment SUVmax (≥ 7.5) and further chemotherapy after radiotherapy showed significant differences in univariate and multivariate analyses. CONCLUSION: Good metabolic responses (complete or partial) to radiotherapy were achieved in 92.6% of the myeloid sarcoma patients. Radiation doses < 3000 cGy10 and increased SUVmax were related to treatment failure and high SUVmax before radiotherapy was a factor influencing SUVmax reduction. Further large-scale studies are needed.

A Study on Minimizing Welding Deformation of Joints for the Sealing of Emission After-Treatment Structure.

As the environmental pollution issue has recently become significant, environmental regulations in Europe and the United States are being strengthened. Thus, there is a demand for the quality improvement of emission after-treatment systems to satisfy the strengthened environmental regulations. Reducing the amount of welding heat distortion by optimization of the welding order of each part could be a solution for quality improvement since the emission after-treatment system consists of many parts and each assembly is produced by welding individual ones. In this research, a method to derive a welding sequence that effectively minimizes welding deformation was proposed. A two-stage simulation was performed to obtain the optimal welding sequence. In the first stage, the welding sequence was derived by analyzing the number of welding groups in each assembly of a structure. The derived welding sequence was verified by performing a thermal elasto-plastic analysis and comparing it with the experimental results.

Crash Analysis of Aluminum/CFRP Hybrid Adhesive Joint Parts Using Adhesive Modeling Technique Based on the Fracture Mechanics.

This study describes the numerical simulation results of aluminum/carbon-fiber-reinforced plastic (CFRP) hybrid joint parts using the explicit finite-element solver LS-DYNA, with a focus on capturing the failure behavior of composite laminates as well as the adhesive capacity of the aluminum-composite interface. In this study, two types of adhesive modeling techniques were investigated: a tiebreak contact condition and a cohesive zone model. Adhesive modeling techniques have been adopted as a widely commercialized model of structural adhesives to simulate adhesive failure based on fracture mechanics. CFRP was studied with numerical simulations utilizing LS-DYNA MAT54 to analyze the crash capability of aluminum/CFRP. To evaluate the simulation model, the results were compared with the force-displacement curve from numerical analysis and experimental results. A parametric study was conducted to evaluate the effect of different fracture toughness values used by designers to predict crash capability and adhesive failure of aluminum/CFRP parts.

Mechanical Changes of the Lumbar Intervertebral Space and Lordotic Angle Caused by Posterior-to-Anterior Traction Using a Spinal Thermal Massage Device in Healthy People.

BACKGROUND: The axial (horizontal) traction approach has been traditionally used for treatment of low back pain-related spinal disorders such as nuclear protrusion, primary posterolateral root pain, and lower thoracic disc herniation; however, it is known to have some technical limitations due to reductions of the spinal curve. Lumbar lordosis plays a pivotal function in maintaining sagittal balance. Recently, vertical traction and combination traction have been attracting attention due to improving therapeutic outcomes, although evidence of their clinical application is rare; therefore, this study was conducted to investigate the mechanical changes of lumbar intervertebral space, lordotic angle, and the central spinal canal area through vertical traction treatment using a spinal massage device in healthy participants. METHODS: In total, 10 healthy subjects with no musculoskeletal disorders and no physical activity restrictions participated. The participants lay on the experimental device (CGM MB-1901) in supine extended posture and vertical traction force was applied in a posterior-to-anterior direction on the L3-4 and L4-5 lumbar sections at level 1 (baseline) and level 9 (traction mode). Magnetic resonance (MR) images were recorded directly under traction mode using the MRI scanner. The height values of the intervertebral space (anterior, center, and posterior parts) and lordosis angle of the L3-4 and L4-5 sections were measured using Image J software and the central spinal canal area (L4-5) was observed through superimposition method using the MR images. All measurement and image analyses were conducted by 2 experienced radiologists under a single-blinded method. RESULTS: The average height values of the intervertebral space under traction mode were significantly increased in both L3-4 and L4-5 sections compared to baseline, particularly in the anterior and central parts but not in the posterior part. Cobb's angle also showed significant increases in both L3-4 and L4-5 sections compared to baseline (p < 0.001). The central spinal canal area showed a slightly expanded feature in traction mode. CONCLUSIONS: In this pilot experiment, posterior-to-anterior vertical traction on L3-4 and L4-5 sections using a spinal massage device caused positive and significant changes based on increases of the intervertebral space height, lumbar lordosis angle, and central spinal canal area compared to the baseline condition. Our results are expected to be useful as underlying data for the clinical application of vertical traction.

Clinical outcome and toxicity of radiotherapy for inferior vena cava tumor thrombus in HCC patients: A retrospective study.

ABSTRACT: Hepatocellular carcinoma (HCC) involving the inferior vena cava rarely occurs, but its prognosis is extremely poor, with no established treatment to date. This study aimed to analyze the clinical outcome and toxicity of radiotherapy (RT) targeting inferior vena cava tumor thrombus (IVCTT) in HCC patients.From November 2011 to July 2020, medical record of 19 HCC patients who were treated with RT for IVCTT was retrospectively reviewed. RT was delivered using 3-dimensional conformal radiation therapy, intensity-modulated radiation therapy, and stereotactic body radiation therapy. The median radiation dose was 50 Gy (range, 45-55.8 Gy) for intensity-modulated radiation therapy and three-dimensional conformal radiotherapy. Stereotactic body radiation therapy was performed in 5 patients, for a total of 32 Gy in 4 fractions.The median follow-up duration was 8.1 months (range, 3.3-26.5 months). The median overall survival was 9.4 months (range, 3.7-26.5 months), and the 1-year overall survival rate was 37.1%. Eight of 19 patients (42.1%) had extrahepatic metastasis at the start of RT. Six of 11 patients (54.5%) who did not have extrahepatic metastasis at the start of RT showed extrahepatic metastasis after RT. The major cause of death was progression of extrahepatic metastasis (11 patients, 57.9%). The overall response rate of IVCTT for RT was 84.2%, and the local control rate at the time of the last follow-up was 89.4%. After RT, the most common first progression site was the lungs (9 patients, 47.4%). Most toxicities were grade 1 to 2 gastrointestinal (26.3%) and liver enzyme elevation (68.4%). Three patients occurred pulmonary embolism after RT later than 5 months after.RT is a feasible and safe local therapy for IVCTT, with favorable tumor control and acceptable toxicity. Extrahepatic metastasis is the major progression pattern and a leading cause of death in patients treated with RT. The combination of effective systemic therapy with RT may have to be considered.

Sigmoidal Dependence of Electrical Conductivity of Thin PEDOT:PSS Films on Concentration of Linear Glycols as a Processing Additive.

We investigate the sigmoidal concentration dependence of electrical conductivity of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) processed with linear glycol-based additives such as ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), hexaethylene glycol (HEG), and ethylene glycol monomethyl ether (EGME). We observe that a sharp transition of conductivity occurs at the additive concentration of ~0.6 wt.%. EG, DEG, and TEG are effective in conductivity enhancement, showing the saturation conductivities of 271.8, 325.4, and 326.2 S/cm, respectively. Optical transmittance and photoelectron spectroscopic features are rather invariant when the glycols are used as an additive. Two different figures of merit, calculated from both sheet resistance and optical transmittance to describe the performance of the transparent electrodes, indicate that both DEG and TEG are two most effective additives among the series in fabrication of transparent electrodes based on PEDOT:PSS films with a thickness of ~50-60 nm.

Current Trends in the Quality Assessment of Colorectal Cancer Practice and Treatment in South Korea during 2012-2017.

PURPOSE: Colorectal cancer (CRC) is increasing in South Korea due to westernized eating habits and regular health check-ups. The Korean Health Insurance Review and Assessment Service (HIRA) has conducted a national quality assessment of the treatment of CRC. This study examined the quality assessment report of the Korean HIRA and analyzed the status of practice pattern and the epidemiology of CRC in South Korea. MATERIALS AND METHODS: The number of subjects was determined based on the number of surgical procedures in each institution during 2012-2017. The institution types were classified according to the number of beds and the composition of oncologic specialists. Twenty-one indicators for diagnosis, chemotherapy, radiotherapy, surgery, pathology, and mortality were analyzed and the interinstitutional variation for each indicator was calculated. RESULTS: Among 21 evaluation indices, indicators related to medical records, receipt of chemotherapy with a high coefficient of variation of ≥ 0.1% were improved over 6 years until the survey in 2017. In the analysis of indices affecting surgical mortality, the regional lymph node resection and examination rate (p=0.022) showed a negative correlation with surgical mortality. Hospitalization stay (p < 0.001) and hospitalization cost (p=0.002) were positively correlated with surgical mortality. CONCLUSION: This study showed that the treatment quality and examination status for CRC in South Korea were appropriate for improving relevant medical records, receipt of chemotherapy, maintaining the quality of treatment, and mortality. These analyses could be the basis for developing an improved quality assessment program worldwide.

Non-invasive Assessment of Central Retinal Artery Pressure: Age and Posture-dependent Changes.

Purpose: Assessment of Ocular Perfusion Pressure (OPP) requires estimation of the Mean Central Retinal Artery Pressure (MCRAP) [OPP = MCRAP-IOP]. In a seated position, MCRAP is currently estimated as 2/3 of the Mean Arterial Pressure (MAP) to account for the hydrostatic reduction of MAP at eye level. We tested a surrogate method for direct MCRAP assessment by measuring MAP with Arm-Up and cuff at eye level (AUMAP) at different postures and ages. Methods: MAP and AUMAP were assessed in a mixed population of 136 subjects (mean age 44 ± 17.39 years) including healthy participants (N = 30) and patients with optic neuropathies (Glaucoma suspects, N = 14; Open-Angle Glaucoma, N = 26, LHON, N = 19; MS, N = 47) not expected to alter systemic blood pressure. None of the subjects had history of carotid stenosis or pharmacological treatment to regulate blood pressure. AUMAP was also tested in two subgroups in supine (N = 42) and -10° Head Down body Tilt position (HDT, N = 46). Results: In the seated position, both 2/3MAP and AUMAP increased with increasing age, however with steeper (2x) slope for AUMAP (P < .0001). With decreasing angle of body tilt, AUMAP increased while MAP decreased. The mean AUMAP/MAP ratio (posture coefficient) was, seated, 0.73 (SE 0.003); supine, 0.90 (SE 0.005); HDT, 0.97 (SE 0.005). In the seated position only, the AUMAP/MAP ratio significantly increased with age (P < .0001). Mean posture coefficients obtained with AUMAP were in the range of those based on either direct ophthalmodynamometric measurements or hydrostatic estimations. Conclusions: Surrogate measurement of MCRAP in individual subjects is feasible using the simple AUMAP approach that provides a straightforward estimation of OPP (OPP = AUMAP - IOP) at different body postures. The standard method OPP = 2/3*MAP-IOP in the seated posture underestimates OPP at older ages. Clinical estimation of OPP would benefit from the use of AUMAP, in particular for head-down postures.

Solid-State Organic Electrolyte-Gated Transistors Based on Doping-Controlled Polymer Composites with a Confined Two-Dimensional Channel in Dry Conditions.

We report comprehensive and comparative studies on chemical and electrochemical controls of doping characteristics of various poly(3,4-ethylenedioxythiophene) (PEDOT) composites complexed with sulfonates. Chemical treatment of PEDOT composites was conducted with a dedoping agent, tetrakis(dimethylamino)ethylene (TDAE), resulting in the changes in conformation and bulk charge-carrier density. Electrochemical control of doping states was done with a solid-state ionogel based on an ionic liquid dispersed in a polymer matrix. With this approach, we can fabricate solid-state organic electrolyte-gated transistors (OEGTs) with a large current modulation, a high mobility of holes, and a low driving voltage. Our OEGTs are operational in a dry environment and, surprisingly, form the two-dimensional channel of the interfacial charge carriers modulating the conductance under gate bias, unlike conventional liquid-based OEGTs. The charge-carrier mobility and the on-to-off current ratio reach up to ∼7 cm2 V-1 s-1 and over 104, respectively, from the chemically dedoped PEDOT composites. The ionogel-based gating of the layer of TDAE-treated PEDOT composites induces a reversible transition between a highly doped bipolaronic state and neutral/polaronic states, as revealed by the absorption profiles under gate bias. We also demonstrate in-plane OEGTs, in which the dedoped channel and the conductive source/drain electrodes are made of a single PEDOT composite layer.