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Doping of conjugated polymers (CPs) is a promising strategy to obtain solution‐processable and highly conductive films; however, the improvement in electrical conductivity is limited owing to the relatively poor carrier mobility of CPs. Herein, a CP with excellent molecular doping ability, i.e., poly[2‐([2,2'‐bithiophen]‐5‐yl)‐3,8‐difluoro‐5,10‐bis(5‐octylpentadecyl)‐5,10‐dihydroindolo[3,2‐b]indole] (PIDF‐BT) is wrapped onto the surface of single‐walled carbon nanotubes (SWCNTs). The resulting PIDF‐BT@SWCNT simultaneously achieves excellent solution dispersibility and a high electrical conductivity of over 5000 S cm−1 through AuCl3 doping. The doping mechanism is systematically studied using spectroscopic analysis, and the four‐probe field‐effect transistor based on the doped PIDF‐BT@SWCNT confirms a carrier mobility up to 138 cm2 V−1 s−1. The carrier‐transfer barrier energy is related to the Schottky barrier between the SWCNT and PIDF‐BT, which can be controlled by doping. Finally, when the doped PIDF‐BT@SWCNT is applied to a thermoelectric device, a power factor exceeding 210 μW m−1 K−2 is achieved because of its high electrical conductivity, even if the increased carrier density reduces the Seebeck coefficient.

Cooperative transitions have acquired much attention for low transition barriers, ultrafast kinetics, and structural reversibility but cooperative transitions are rare in molecular crystals and their origin is poorly understood. Here the authors show that reorientation of the alkyl side chains in a 2-dimensional quinoidal terthiophene triggers cooperative behavior, and establish alkyl chain engineering to control the polymorphic behavior.

AbstractThe fungal-like family Saprolegniaceae (Oomycota), also called “water mold,” includes mostly aquatic saprophytes as well as notorious aquatic animal pathogens. Most studies on Saprolegniaceae have been biased toward pathogenic species that are important to aquaculture rather than saprotrophic species, despite the latter’s crucial roles in carbon cycling of freshwater ecosystems. Few attempts have been made to study the diversity and ecology of Saprolegniaceae; thus, their ecological role is not well-known. During a survey of oomycetes between 2016 and 2021, we investigated the diversity and distribution of culturable Saprolegniaceae species in freshwater ecosystems of Korea. In the present study, members of Saprolegniaceae were isolated and identified at species level based on their cultural, morphological, and molecular phylogenetic analyses. Furthermore, substrate preference and seasonal dynamics for each were examined. Most of the species were previously reported as animal pathogens; however, in the present study, they were often isolated from other freshwater substrates, such as plant debris, algae, water, and soil sediment. The relative abundance of Saprolegniaceae was higher in the cold to cool season than that in the warm to hot season of Korea. This study enhances our understanding of the diversity and ecological attributes of Saprolegniaceae in freshwater ecosystems.

Background Early‐stage unilateral moyamoya disease (MMD) is difficult to discriminate from isolated intracranial atherosclerotic stenosis, and identification of contralateral progression may aid in the diagnosis of MMD. The RNF213 (ring finger protein 213) R4810K variant is a strong genetic susceptibility factor for MMD; however, the role of contralateral progression in unilateral MMD is unknown. Methods and Results Patients who had undergone RNF213 R4810K genotyping with suspected unilateral MMD between January 2017 and August 2021 from 2 tertiary university hospitals were retrospectively reviewed. We compared the clinical features and radiographic outcomes of patients with and without this variant. The risk factors of contralateral progression in patients with suspected unilateral MMD were evaluated. The RNF213 R4810K variant was observed in 72 of 123 patients with suspected unilateral MMD, all of which were heterozygous. The allele frequency of the R4810K variant was significantly higher in the suspected unilateral MMD group compared with the historical control group (29.3% versus 1.2%; P

Background For children and adolescents with cancer, going back to school is a key milestone in returning to “normal life.” Purpose To identify the support vital for a successful transition, we evaluated the parents’ needs and the challenges they face when their children return to school. Methods This multi-institutional study was conducted by the Korean Society of Pediatric Hematology and Oncology. The written survey comprised 24 questions and was completed by 210 parents without an interviewer. Results Most parents (165 of 206) reported that their children experienced difficulties with physical status (n=60), peer relationships (n=30), academic performance (n=27), emotional/behavioral issues (n=11), and relationships with teachers (n=4) on reentering school. Parents wanted to be kept informed about and remain involved in their children’s school lives and reported good parent-teacher communication (88 of 209, 42.1%). Parents reported that 83.1% and 44.9% of teachers and peers, respectively, displayed an adequate understanding of their children’s condition. Most parents (197 of 208) answered that a special program is necessary to facilitate return to school after cancer therapy that offers emotional support (n=85), facilitates social adaptation (n=61), and provides tutoring to accelerate catch up (n=56), and continued health care by hospital outreach and school personnel (n=50). Conclusion In addition to scholastic aptitude-oriented programs, emotional and psychosocial support is necessary for a successful return to school. Pediatric oncologists should actively improve oncology practices to better integrate individualized school plans and educate peers and teachers to improve health literacy to aid them in understanding the needs of children with cancer.

Abstract Background Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS. Methods Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform. Results Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (n = 28), and followed by ANK1 (n = 19), SLC4A1 (n = 3), SPTA1 (n = 2), EPB41 (n = 1), and EPB42 (n = 1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations. Conclusions This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.

Background : : von Willebrand disease (VWD) is one of the most common inherited bleeding disorders. However, the number of patients who register to the Korea Hemophilia Foundation (KHF) is much lower than the expected prevalence rate and only few hospitals perform tests for diagnosis autonomously. Thus, we surveyed practical realities of VWD in Yeungnam region. Methods : : Patients with VWD (N=267) who were diagnosed at eleven university hospitals from March 1995 to March 2018 were enrolled in this study. We evaluated the medical records from each hospital retrospectively. Results : : Two hundred and twenty-eight children and 39 adults met the diagnostic criteria for VWD. Seventy-eight (57.4%) patients had the blood type O. Fifty-eight patients were definite type 1 (21.7%), 151 were possible type 1 (56.6%), and the others were type 2. Abnormal laboratory findings were the most common factor for the diagnosis in children. VWF mutations were detected in 17 patients. Patients with a family history showed age of diagnosis of 9 y, which is higher than in those with no family history (6 yr), and also showed a higher rate of significant bleeding (32.1% vs. 14.2%). VWF:RCo and VWF:Ag tests were performed in-hospital at only 1 of 11 hospitals. Twelve of 267 patients were enrolled at the KHF (4.5%). Conclusion : : A high rate of out-sourcing studies may result in inaccurate diagnosis. The registration rate to the KHF is still lower than the prevalence rate. A comprehensive nationwide registration system is necessary in order to identify the actual prevalence rate and promote the diagnosis of VWD in Korea.

Background/Aims Differentiating extraluminal compressions from true subepithelial tumors in the duodenum by endoscopy alone is difficult. Endoscopic ultrasonography (EUS) is one of the most useful diagnostic modalities for this purpose. Extraluminal compression in the duodenum is occasionally observed, but its clinical significance has not been reported. Therefore, the aim of this study was to evaluate the clinical significance of extraluminal compression in the duodenum according to lesion location.Materials and Methods We retrospectively evaluated 22 patients diagnosed as having extraluminal compression in the duodenum based on EUS findings between January 2006 and December 2017. Some patients underwent abdominal computed tomography for accurate diagnosis. Results The location of the extraluminal compression was the duodenal bulb in 10 cases, the superior duodenal angle in 10 cases, and the second portion of the duodenum in 2 cases. Of the 22 cases, 12 were caused by normal structures, including vessels, the right kidney, the gallbladder, and the pancreas, and 10 were caused by pathological lesions, including the hepatic cyst, remnant cystic duct and dilated common bile duct after cholecystectomy; gallstones, gallbladder polyps, remnant cystic duct cancer, and pseudomyxoma peritoneii. The anterior wall of the duodenum was the most frequent location of extraluminal compression. However, the lesions in the anterior wall of the duodenal bulb and superior duodenal angle showed a high frequency of pathologic lesions, including malignancy. Conclusions If the extraluminal compression is found in the anterior wall of the duodenum, EUS is needed because of the high frequency of pathological lesions.

Spontaneous intramural hematoma is a rare complication of oral anticoagulants, and its incidence is expected to increase because of the increasing number of elderly patients undergoing anticoagulant therapy. Clinical manifestations of spontaneous intramural hematoma vary from mild abdominal pain to intestinal obstruction or acute abdomen. Early diagnosis is important because most patients can be treated successfully without surgery. The role of endoscopy in the diagnosis of intramural hematoma is not well established because almost all cases are diagnosed non-invasively with computed tomography scans. However, confirmation of the intramural hematoma through direct visualization of the involved bowel mucosa is helpful, if the imaging diagnosis is uncertain. We report a case of anticoagulant-induced spontaneous intramural hematoma, which was diagnosed using endoscopy, with relevant literature review.

Acute myeloid leukemia (AML) is the second most common pediatric leukemia, with a survival rate of 70%. In this retrospective study, we evaluated the treatment outcomes of pediatric AML among 144 patients diagnosed between 2000 and 2013. After induction, 80.6% of patients achieved complete remission (CR). The 5-year overall survival (OS) and event-free survival (EFS) rates were 58.8 ± 4.2% and 49.8 ± 4.2%, respectively. Based on the response to induction therapy, the 5-year OS was 66.9 ± 5.7% in patients with CR (p < 0.001). Ninety-nine patients with CR after induction therapy were examined, and their 5-year OS and EFS were 66.4 ± 4.9% and 56.3 ± 5.1%, respectively. The 5-year OS rates according to treatment were 59.9 ± 7.4% in the chemotherapy group and 72.3 ± 6.3% in the hematopoietic stem cell transplantation (HSCT) group (p = 0.089). The EFS was 50.1 ± 7.4% in the chemotherapy group and 61.7 ± 6.9% in the HSCT group (p = 0.098). OS and EFS according to cytogenetics were insignificant. Our findings confirmed that the response to induction treatment was important for survival and HSCT had no significant survival benefits compared with those of chemotherapy. Moreover, many early induction deaths under the age of 2 years were observed.

An m-sequence (PN sequence) preestimator scheme for direct-sequence spread spectrum (DS-SS) signal acquisition by using block sequence estimation (BSE) is proposed and analyzed. The proposed scheme consists of an estimator and a verifier which work according to the PN sequence chip clock, and provides not only the enhanced chip estimates with a threshold decision logic and one-chip error correction among the first m received chips, but also the reliability check of the estimates with additional decision logic. The probabilities of the estimator and verifier operations are calculated. With these results, the detection, the false alarm, and the missing probabilities of the proposed scheme are derived. In addition, using a signal flow graph, the average acquisition time is calculated. The proposed scheme can be used as a preestimator and easily implemented by changing the internal signal path of a generally used digital matched filter (DMF) correlator or any other correlator that has a lot of sampling data memories for sampled PN sequence. The numerical results show rapid acquisition performance in a relatively good CNR.

Orthogonal frequency division multiple access (OFDMA) is a key multiple access technique for the long term evolution (LTE) downlink. However, high peak-to-average power ratio (PAPR) can cause the degradation of power efficiency. The well-known PAPR reduction technique, dummy sequence insertion (DSI), can be a realistic solution because of its structural simplicity. However, the large usage of subcarriers for the dummy sequences may decrease the transmitted data rate in the DSI scheme. In this paper, a novel DSI scheme is applied to the LTE system. Firstly, we obtain the null subcarriers in single-input single-output (SISO) and multiple-input multiple-output (MIMO) systems, respectively; then, optimized dummy sequences are inserted into the obtained null subcarrier. Simulation results show that Walsh-Hadamard transform (WHT) sequence is the best for the dummy sequence and the ratio of 16 to 20 for the WHT and randomly generated sequences has the maximum PAPR reduction performance. The number of near optimal iteration is derived to prevent exhausted iterations. It is also shown that there is no bit error rate (BER) degradation with the proposed technique in LTE downlink system.

Hyperplastic anterior choroidal artery (AchA) is an extremely rare congenital vascular variant that can be mistaken for other cerebral arteries. This case report presents a 38-year-old man who presented with a severe sudden-onset headache and was diagnosed with a ruptured aneurysm originating from a hyperplastic AchA. The aneurysm was successfully treated with coil embolization, but recurrence was detected after eight months, leading to additional surgical intervention. The discussion highlights the classification of hyperplastic AchA and emphasizes the importance of recognizing this anatomical variant to avoid complications during treatment. This case report underscores the need for awareness and understanding of hyperplastic AchA in the management of cerebral aneurysms. [ABSTRACT FROM AUTHOR]

Parasitic flatworms cause various clinical and veterinary infections that impart a huge burden worldwide. The most clinically impactful infection is schistosomiasis, a neglected tropical disease caused by parasitic blood flukes. Schistosomiasis is treated with praziquantel (PZQ), an old drug introduced over 40 years ago. New drugs are urgently needed, as while PZQ is broadly effective it suffers from several limitations including poor efficacy against juvenile worms, which may prevent it from being completely curative. An old compound that retains efficacy against juvenile worms is the benzodiazepine meclonazepam (MCLZ). However, host side effects caused by benzodiazepines preclude development of MCLZ as a drug and MCLZ lacks an identified parasite target to catalyze rational drug design for engineering out human host activity. Here, we identify a transient receptor potential ion channel of the melastatin subfamily, named TRPMMCLZ, as a parasite target of MCLZ. MCLZ potently activates Schistosoma mansoni TRPMMCLZ through engagement of a binding pocket within the voltage-sensor-like domain of the ion channel to cause worm paralysis, tissue depolarization, and surface damage. TRPMMCLZ reproduces all known features of MCLZ action on schistosomes, including a lower activity versus Schistosoma japonicum, which is explained by a polymorphism within this voltage-sensor-like domain-binding pocket. TRPMMCLZ is distinct from the TRP channel targeted by PZQ (TRPMPZQ), with both anthelmintic chemotypes targeting unique parasite TRPM paralogs. This advances TRPMMCLZ as a novel druggable target that could circumvent any target-based resistance emerging in response to current mass drug administration campaigns centered on PZQ. [ABSTRACT FROM AUTHOR]

Flow-diverting stents (FDSs) have proven advantageous for the treatment of large, fusiform, and dissecting aneurysms that are otherwise difficult to treat. Retreatment strategies for recurrent large or giant aneurysms after FDSs are limited to overlapping implantation of an additional FDS or definitive occlusion of the parent vessel. We report a recurrent giant aneurysm that was initially treated with an FDS with coils and was successfully treated with an additional FDS. Visual symptoms due to the mass effect of the recurrent aneurysm were completely resolved, and follow-up digital subtraction angiography revealed complete obliteration of the aneurysm. Additional FDS implantation for the retreatment of incompletely occluded aneurysms after the initial FDS treatment may be feasible and safe. Further studies are required to validate these results. [ABSTRACT FROM AUTHOR]

Objective: To report our experience with intraprocedural rupture (IPR) of intracranial aneurysms during endovascular treatment and evaluate alterations in vital signs as independent prognostic factors to predict the outcomes of IPR. Methods: Between January 2008 and August 2021, 34 patients (8 ruptured and 26 unruptured) were confirmed to have IPR based on our dataset with 3178 endovascular coiling procedures. The patients who underwent additional surgeries related to IPR were classified as the OP group (n=9), while those who did not receive additional surgeries were classified as the non-OP group (n=25). Vital signs were recorded during the procedure by anesthesiologists and analyzed. Results: Of the 34 patients included in this study, eight initially presented with subarachnoid hemorrhage due to a ruptured aneurysm. The clinical outcomes at discharge were significantly different between the two groups (p=0.046). In the OP group, five patients showed favorable outcomes at discharge, while four showed unfavorable outcomes. In the non-OP group, 23 patients showed favorable outcomes at discharge while two patients showed unfavorable outcomes. Maximal (MAX) systolic blood pressure (SBP) (odds ratio [OR] 1.520, 95% confidence interval [CI] 1.084-2.110; p=0.037) and higher differential value MAX-median blood pressure (MBP) (OR 1.322, 95% CI 1.029-1.607; p=0.044) remained independent risk factors for poor prognosis after IPR on multivariate logistic regression analysis. Conclusions: The MAX SBP and the difference between the maximal and baseline values of MBP are key factors in predicting the prognosis of patients after IPR, as well as providing useful information for predicting the outcome. Further research is required to confirm the relationship between naive pressure and prognosis. [ABSTRACT FROM AUTHOR]