Sodium-assisted passivation of grain boundaries and defects in Cu2ZnSnSe4 thin films.

The long stagnation of the photo-conversion efficiency of kesterites below 13% is a source of frustration in the scientific community. In this study, we investigated the effects of sodium on the passivation of grain boundaries and defects in Cu2ZnSnSe4 (CZTSe) grown on a soda-lime glass (SLG) and borosilicate (BS) glass. Because BS glass does not inherently contain sodium, we placed a thin layer of NaF between CZTSe and Mo. The composition of the samples is Cu-poor and Zn-rich. The distribution of sodium and its contributions to phase formation and defects were examined by cross-sectional energy-dispersive X-ray profiling, Raman scattering spectroscopy and imaging, surface potential and photoluminescence. From the experimental results, it can be strongly claimed that sodium ions segregate predominantly near the grain boundaries and reduce CuZn-related defects. These local surface imaging analyses provided the exact locations of the secondary phases. In particular, the photo-assisted scanning probe method enabled us to observe the changes in the optoelectrical properties of the thin films and the carrier behavior within the materials. Further studies with distinct alkali ions and optimal processing conditions will pave a way to improve the performance of kesterite solar cells.

Impact of H-Doping on n-Type TMD Channels for Low-Temperature Band-Like Transport.

Band-like transport behavior of H-doped transition metal dichalcogenide (TMD) channels in field effect transistors (FET) is studied by conducting low-temperature electrical measurements, where MoTe2 , WSe2 , and MoS2 are chosen for channels. Doped with H atoms through atomic layer deposition, those channels show strong n-type conduction and their mobility increases without losing on-state current as the measurement temperature decreases. In contrast, the mobility of unintentionally (naturally) doped TMD FETs always drops at low temperatures whether they are p- or n-type. Density functional theory calculations show that H-doped MoTe2 , WSe2 , and MoS2 have Fermi levels above conduction band edge. It is thus concluded that the charge transport behavior in H-doped TMD channels is metallic showing band-like transport rather than thermal hopping. These results indicate that H-doped TMD FETs are practically useful even at low-temperature ranges.

Simultaneous growth of Ga2S3 and GaS thin films using physical vapor deposition with GaS powder as a single precursor.

High quality gallium sulfide II (GaS) and gallium sulfide III ([Formula: see text]) thin films on [Formula: see text]/Si substrates were simultaneously grown by using physical vapor deposition with GaS powder as a single precursor. By controlling the substrate temperature, we can selectively grow either GaS or Ga2S3 thin films on SiO2/Si substrates. Relatively high and low substrate temperature conditions resulted in Ga2S3 and GaS thin films, respectively. The synthesized thin films were characterized by x-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, atomic force microscopy, and x-ray photoelectron spectroscopy analyses.

Unclassified Variants of BRCA1 and BRCA2 in Korean Patients With Ovarian Cancer.

OBJECTIVE: The aim of the present study was to investigate unclassified variants (UVs) in BRCA1 and 2 of Korean patients with ovarian cancer. METHODS: We retrospectively analyzed 138 patients diagnosed with ovarian/fallopian tubal/peritoneal cancer between January 2013 and January 2016, whose BRCA genetic test results and clinical characteristics were available for review. Patient peripheral blood lymphocyte specimens were assessed for BRCA mutations and variations by direct sequencing. Identified UVs were classified according to several algorithms. RESULTS: The results of genetic testing revealed 31 (22.5%, 31/138) pathogenic BRCA mutations (24 BRCA1, 7 BRCA2 mutations). The BRCA1 c.390C>A mutation was observed in 4 patients (12.9%, 4/31). Thirty-four (24.6%, 34/138) BRCA UVs were identified in 33 patients. Of these, the BRCA1 c.4883T>C and BRCA2 c.8187G>T variants were each detected in 4 patients (4/34, 11.8%). According to the used algorithms and cosegregation test, the BRCA1 c.5339T>C and BRCA2 c.8437_8439delGGA variants were both predicted to be likely pathogenic. CONCLUSIONS: The 2 identified likely pathogenic UVs require further verification with clinical evidence. Clarifying the clinical significance of UVs is an increasingly important step for cancer treatment in the current era of precision medicine.

Systematic Review of the Long-term Surgical Outcomes of Discoid Lateral Meniscus.

PURPOSE: To evaluate the surgical treatment of the discoid lateral meniscus (DLM) with long-term follow-up and to search which factors are related to good clinical or radiological outcomes. METHODS: Search was performed using a MEDLINE, EMBASE, and Cochrane database, and each of the selected studies was evaluated for methodological quality using a risk of bias (ROB) covering 7 criteria. Clinical and radiological outcomes with more than 5 years of follow-up were evaluated after surgical treatment of DLM. They were analyzed according to the age, follow-up period, kind of surgery, DLM type, and alignment. RESULTS: Eleven articles (422 DLM cases) were included in the final analysis. Among 7 criteria, 3 criteria showed little ROB in all studies. However, 4 criteria showed some ROB ("Yes" in 63.6% to 81.8%). The minimal follow-up period was 5.5 years (weighted mean follow-up: 9.1 years). Surgical procedures were performed with open or arthroscopic partial central meniscectomy, subtotal meniscectomy, total meniscectomy, or partial meniscectomy with repair. The majority of the studies showed good clinical results. Mild joint space narrowing was reported in the lateral compartment, but none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy could be related to degenerative change. The majority of the complications was osteochondritis dissecans at the lateral femoral condyle (13 cases) and reoperation was performed by osteochondritis dissecans (4 cases), recurrent swelling (2 cases), residual symptom (1 case), stiffness (1 case), and popliteal stenosis (1 case). CONCLUSIONS: Good clinical results were obtained with surgical treatment of symptomatic DLM. The progression of degenerative change was minimal and none of the knees demonstrated moderate or advanced degenerative changes. Increased age at surgery, longer follow-up period, and subtotal or total meniscectomy were possible risk factors for degenerative changes. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.

Placental Site Trophoblastic Tumors: Analysis of the Clinicopathologic Characteristics of 20 Cases in Korea.

OBJECTIVES: The aim of this study was to evaluate the clinicopathologic features of placental site trophoblastic tumors (PSTTs) in Korea. METHODS/MATERIALS: Twenty patients given a diagnosis of PSTT in Korea (1990-2013) were evaluated retrospectively, including 14 patients identified through a literature review and 6 patients identified through a medical chart review of a single institution. The analysis included patient age, antecedent pregnancies, time since antecedent pregnancy, presenting symptoms, serum ß-human chorionic gonadotropin level, International Federation of Gynecology and Obstetrics stage, treatment, outcome, and follow-up. RESULTS: The mean age of the 20 patients was 32 years (range, 25-53 years). The antecedent pregnancies included 8 term pregnancies, 8 abortions, and 2 molar pregnancies. The time since the antecedent pregnancy was less than 1 year in 16 patients (80%). Nineteen patients (95%) presented with abnormal vaginal spotting or amenorrhea. Serum ß-human chorionic gonadotropin levels ranged from normal to 13,480 mIU/mL, although most patients (80%) had a level less than 1000 mIU/mL. Seventeen patients (85%) presented with stage I disease. Ten patients (50%) underwent hysterectomy, and 14 patients (70%) were treated with chemotherapy with or without hysterectomy. In 11 evaluated patients, the median mitotic count index was 3.4 (0.4-10) per 10 high-power fields. The median follow-up time was 17 months (range, 1-68 months). There was no recurrence or death from disease. CONCLUSIONS: Korean patients with PSTT often have early-stage disease, which has a favorable prognosis even with fertility-preserving therapy. However, international studies are necessary to determine the optimal treatment and prognostic factors.

Germline Mutations of BRCA1 and BRCA2 in Korean Ovarian Cancer Patients: Finding Founder Mutations.

OBJECTIVES: To investigate and analyze the BRCA mutations in Korean ovarian cancer patients with or without family history and to find founder mutations in this group. METHODS/MATERIALS: One hundred two patients who underwent a staging operation for pathologically proven epithelial cancer between January 2013 and December 2014 were enrolled. Thirty-two patients declined to analyze BRCA1/2 gene alterations after genetic counseling and pedigree analysis. Lymphocyte specimens from peripheral blood were assessed for BRCA1/2 by direct sequencing. RESULTS: BRCA genetic test results of 70 patients were available. Eighteen BRCA1/2 mutations and 17 unclassified variations (UVs) were found. Five of the BRCA1/2 mutations and 4 of the UVs were not reported in the Breast Cancer Information Core database. One BRCA2 UV (8665_8667delGGA) was strongly suspicious to be a deleterious mutation. BRCA1/2 mutations were identified in 11 (61.1%) of 18 patients with a family history and in 7 (13.5%) of 52 patients without a family history.Candidates for founder mutations in Korean ovarian cancer patients were assessed among 39 BRCA1/2 mutations from the present study and from literature reviews. The analysis showed that 1041_1043delAGCinsT (n = 4; 10.2%) and 3746insA (n = 4; 10.2%) were possible BRCA1 founder mutations. Only one of the BRCA2 mutations (5804_5807delTTAA) was repeated twice (n = 2; 5.1%). CONCLUSIONS: The prevalence of BRCA1/2 mutations in Korean ovarian cancer patients irrespective of the family history was significantly higher than previously reported. Possible founder mutations in Korean ovarian cancer patients were identified.

Photodynamic therapy for premalignant lesions of the vulva and vagina: A long-term follow-up study.

BACKGROUND AND OBJECTIVE: We aimed to evaluate responses to photodynamic therapy (PDT) and its long-term efficacy in preserving normal anatomy and function in women with premalignant lesions of the lower genital tract. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients received PDT for vulvar intraepithelial neoplasia (VIN), vaginal intraepithelial neoplasia (VAIN), or vulvar Paget's disease between January 2003 and December 2013. Patients underwent colposcopy and/or vulvoscopy for assessment of lesions. Surface photoillumination with a 630-nm red laser light was applied to the lesions 48 hours after intravenous injection of 2 mg/kg photosensitizer (PSZ; Photogem®). The light dose to the lesions was 150 J/cm2 . RESULTS: The median age of the 15 patients (VIN II: 3, VIN III: 4, VAIN II: 2, VAIN III: 3, Paget's disease: 3) was 42.3 years. The complete response (CR) rate was 80% (12/15) at the 3-month follow-up and 71.4% (10/14) at the 1-year follow-up. There were two cases of persistent disease at the 3-month follow-up. One patient with persistent disease underwent partial vulvectomy three times for repetitive recurrence, and the other received secondary PDT with topical 5-aminolevulinic acid (5-ALA) and subsequently showed no evidence of disease (NED). Another patient achieved 90% remission through a combination of additional alternative treatments after showing partial response (PR). In two cases of CR, recurrence was observed at the 1-year follow-up. Regarding adverse events, photosensitivity reactions such as facial edema and urticaria occurred in 13.3% (2/15) and perineal pain occurred in one patient. CONCLUSIONS: PDT may be an effective alternative treatment for premalignant lesions of the female lower genital tract to preserve normal anatomy and sexual function without therapeutic impairment. Lasers Surg. Med. 47:566-570, 2015. © 2015 Wiley Periodicals, Inc.

Anti­adipogenic effect and underlying mechanism of lignan­enriched nutmeg extract on 3T3­L1 preadipocytes.

Nutmeg is the seed derived from Myristica fragrans. Nutmeg seeds contain alkylbenzene derivatives such as myristicin, which are toxic to the human organism, and lignan compounds such as nectandrin B, which possess anti-aging and anti-diabetic properties. However, the anti-adipogenic, prolipolytic and anti-inflammatory effects of lignan-enriched nutmeg extract (LNX) on preadipocytes remain unclear. In the present study, the effects of LNX on lipid accumulation, glycerol release and inflammatory cyclooxygenase-2 (COX-2) expression in differentiated 3T3-L1 preadipocytes were investigated. Oil red O staining demonstrated that treatment with LNX resulted in a concentration-dependent reduction in lipid accumulation in differentiating 3T3-L1 preadipocytes without affecting cell growth. Mechanistically, LNX treatment at 6 µg/ml led to a reduction in phosphorylation levels of signal transducer and activator of transcription 3 (STAT3), whereas it did not influence the peroxisome proliferator-activated receptor gamma (PPAR-γ) and CCAAT enhancer binding protein alpha (C/EBP-α) expression levels during 3T3-L1 preadipocyte differentiation. In addition, LNX treatment at 6 µg/ml led to a decrease in fatty acid synthase (FAS) expression levels on day (D) 2, but not D5 and D8, during preadipocyte differentiation. Treatment with LNX at 6 µg/ml did not affect the expression levels of perilipin A during preadipocyte differentiation. In differentiated 3T3-L1 adipocytes, LNX treatment at 6 µg/ml did not stimulate glycerol release and hormone-sensitive lipase phosphorylation, which are known lipolysis hallmarks. Furthermore, LNX treatment at the doses tested had no effect on tumor necrosis factor alpha-induced COX-2 expression in 3T3-L1 preadipocytes. Collectively, these results demonstrated that LNX has an anti-adipogenic effect on differentiating 3T3-L1 preadipocytes, which is mediated by the downregulation of STAT3 phosphorylation and FAS expression.

Negative Valley Polarization of the Intralayer Exciton via One-Step Growth of H-Type Heterobilayer WS2/MoS2.

Vertical type II van der Waals heterobilayers of transition metal dichalcogenides (TMDs) have attracted wide attention due to their distinctive features mostly arising from the emergence of intriguing electronic structures that include moiré-related phenomena. Owing to strong spin-orbit coupling under a noncentrosymmetric environment, TMD heterobilayers host nonequivalent +K and -K valleys of contrasting Berry curvatures, which can be optically controlled by the helicity of optical excitation. The corresponding valley selection rules are well established by not only intralayer excitons but also interlayer excitons. Quite intriguingly, here, we experimentally demonstrate that unusual valley switching can be achieved using the lowest-lying intralayer excitons in H-type heterobilayer WS2/MoS2 prepared by one-step growth. This TMD combination provides an ideal case for interlayer coupling with an almost perfect lattice match, thereby also in the momentum space between +K and -K valleys in the H-type heterostructure. The underlying valley-switching mechanism can be understood by bright-to-dark conversion of initially created electrons in the valley of WS2, followed by interlayer charge transfer to the opposite valley in MoS2. Our suggested model is also confirmed by the absence of valley switching when the lowest-lying excitons in MoS2 are directly generated in the heterobilayer. In contrast to the H-type case, we show that no valley switching is observed from R-type heterobilayers prepared by the same method, where interlayer charge transfer does not occur between the opposite valleys. We compare the case with the series of valley polarization data from other heterobilayer combinations obtained under different excitation energies and temperatures. Our valley switching mechanism can be utilized for valley manipulation by controlling the excitation photon energy together with the photon helicity in valleytronic devices derived from H-type TMD heterobilayers.

Upregulation of CD9 in ovarian cancer is related to the induction of TNF-α gene expression and constitutive NF-κB activation.

Ovarian cancer is a gynecological cancer with a high death rate. We utilized global gene expression profiles of ovarian carcinomas obtained by complementary DNA (cDNA) microarray to identify ovarian cancer-specific proteins. CD9 was upregulated in ovarian carcinomas, and overexpression of the CD9 protein was detected in ovarian carcinomas by immunohistochemistry. CD9 was also overexpressed in several cancer cell lines, including ovarian cancer cells. In order to elucidate the biological significance of highly expressed CD9 in cancer cells, functional studies of CD9 were performed by ectopic expression, knockdown of CD9 using small interfering RNA (siRNA) and blockage of CD9 activity using the CD9-specific monoclonal antibody ALB6. Ectopic CD9 induced cell survival. In order to identify signaling pathways related to CD9, the gene expressions of CD9/SKOV3 cells were analyzed by cDNA microarray. Among the many upregulated genes, tumor necrosis factor (TNF)-α was induced in CD9/SKOV3 cells. The effect of overexpressed CD9 on the downstream signaling events of TNF-α was further investigated. In CD9/SKOV3 cells, the nuclear factor-kappaB (NF-κB)-signaling pathway was constitutively activated. Knockdown of CD9 by siRNA and blockage of CD9 activity by ALB6 in ovarian cancer cells demonstrated that constitutive activation of NF-κB is CD9 dependent and that CD9 is involved in anti-apoptosis. A CD9 functional study was performed in an ovarian cancer-xenograft mouse by injecting ALB6 into the peritoneum. ALB6 resulted in reduced tumor weight compared with that of control IgG(1). Collectively, these results demonstrate that CD9 functions as an oncogene and represents a target for the development of cancer-specific therapeutics.

Uterine endometrial carcinoma: 10 years' experience with long-term follow-up at a single Korean institution.

AIM: To evaluate prognostic factors in Korean patients with endometrial cancer. METHODS: A retrospective analysis was conducted on 248 patients who were staged surgically at the Samsung Medical Center between 1995 and 2004. Survival data were analyzed using Kaplan-Meier estimates, and multivariate analysis was performed using the Cox regression method. RESULTS: The median age was 51 years (range 21-75), which was younger than in previous studies in Western patients, and the age of 50 years was the cutoff to predict survival. More than half (55.6%) were normal weight or underweight (BMI <25). Multivariate analysis revealed that age, Fédération Internationale de Gynécologie et d'Obstétrique (FIGO) stage, and histopathology were independent predictors of disease-free survival, and FIGO stage and p53 mutation were independent prognostic factors for disease-specific survival (DSS). The 5-year DSS for patients with stage I, II, III and IV disease was 95.6, 93.8, 69.8 and 50%, respectively. The 5-year DSS rate for patients with a p53 mutation was 84.4%, compared with 97.1% for patients without. CONCLUSIONS: Korean patients with endometrial cancer were younger and had a lower BMI than previously reported. Furthermore, age greater than 50 years was predictive of a poor outcome. Age, FIGO stage, histopathology and a p53 mutation were independent prognostic factors for survival.

Insulin-like growth factor-binding protein-5 (IGFBP-5) inhibits TNF-α-induced NF-κB activity by binding to TNFR1.

IGFBP-5 is known to be involved in various cell phenomena such as proliferation, differentiation, and apoptosis. However, the exact mechanisms by which IGFBP-5 exerts its functions are unclear. In this study, we demonstrate for the first time that IGFBP-5 is a TNFR1-interacting protein. We found that ectopic expression of IGFBP-5 induced TNFR1 gene expression, and that IGFBP-5 interacted with TNFR1 in both an in vivo and an in vitro system. Secreted IGFBP-5 interacted with GST-TNFR1 and this interaction was blocked by TNF-α, demonstrating that IGFBP-5 might be a TNFR1 ligand. Furthermore, conditioned media containing secreted IGFBP-5 inhibited PMA-induced NF-κB activity and IL-6 expression in U-937 cells. Coimmunoprecipitation assays of TNFR1 and IGFBP-5 wild-type and truncation mutants revealed that IGFBP-5 interacts with TNFR1 through its N- and L-domains. However, only the interaction between the L-domain of IGFBP-5 and TNFR1 was blocked by TNF-α in a dose-dependent manner, suggesting that the L-domain of IGFBP-5 can function as a TNFR1 ligand. Competition between the L-domain of IGFBP-5 and TNF-α resulted in inhibition of TNF-α-induced NF-κΒ activity. Taken together, our results suggest that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-α inhibitor.

A comparison of pure adenocarcinoma and squamous cell carcinoma of the cervix after radical hysterectomy in stage IB-IIA.

OBJECTIVE: This study was designed to investigate the survival difference between pure adenocarcinoma (AC) and squamous cell carcinoma (SCC) in early cervical cancer (FIGO stage IB-IIA) after radical hysterectomy with or without adjuvant therapy performed at a single institution. METHODS: Patients with AC or SCC between November 1994 and September 2007 at the Samsung Medical Center, Sungkyunkwan University School of Medicine in Seoul, Korea were evaluated. RESULTS: Among the 775 patients, 636 patients had SCC, and 139 patients had pure AC. In basal characteristics, preoperative FIGO stage, adjuvant therapy after surgery, as well as chemotherapeutic regimens, were not different between the two groups. However, the median age was about 5 years younger in pure AC patients than in SCC patients (44 years vs. 49 years, P=.001). In the comparison of pathological findings after surgery between the two groups, there were no differences between the two groups, except for LVSI status. The recurrence rate was higher in the pure AC group than in the SCC group (SCC; 36/636; 5.7%, AC; 20/139; 14.4%, P=<0.001, respectively). The pure AC group had a higher recurrence rate in hematogenous/distant areas than the SCC group (SCC: 8/36; 22.2%, AC; 9/20; 45.0%, P=.076, respectively). In multivariable analysis, positive for pelvic LN and the pure AC cell type were independent factors in both DFS and OS. CONCLUSION: We observed that pure AC of the cervix might entail a worse survival outcome than SCC in patients with early cervical cancer (IB-IIA).

Metastatic urachal carcinoma of the ovary.

A 52-year-old woman had undergone a partial cystectomy for a cystic mass at the dome of the urinary bladder in 1997. The pathological diagnosis was a urachal mucinous cystadenoma with borderline malignancy. Twelve years later, multiple masses were noted on the uterus, ovaries and abdominal wall. She underwent debulking surgery, including a total hysterectomy, bilateral salpingo-oophorectomy, pelvic lymph node dissection, infracolic omentectomy, appendectomy, colon mass removal and abdominal wall mass removal. Remnants of the tumor were seeded throughout the abdominal cavity. The pathological evaluation confirmed metastatic urachal mucinous adenocarcinoma in both ovaries, the abdominal wall, the colon mass, the uterosacral ligament and the bladder. Adjuvant chemotherapy with paclitaxel and carboplatin was administered, which showed stable disease. She is now undergoing second-line chemotherapy.

Bosonic spinons in anisotropic triangular antiferromagnets.

Anisotropic triangular antiferromagnets can host two primary spin excitations, namely, spinons and triplons. Here, we utilize polarization-resolved Raman spectroscopy to assess the statistics and dynamics of spinons in Ca3ReO5Cl2. We observe a magnetic Raman continuum consisting of one- and two-pair spinon-antispinon excitations as well as triplon excitations. The twofold rotational symmetry of the spinon and triplon excitations are distinct from magnons. The strong thermal evolution of spinon scattering is compatible with the bosonic spinon scenario. The quasilinear spinon hardening with decreasing temperature is envisaged as the ordering of one-dimensional topological defects. This discovery will enable a fundamental understanding of novel phenomena induced by lowering spatial dimensionality in quantum spin systems.

Thickness-dependent in-plane anisotropy of GaTe phonons.

Gallium Telluride (GaTe), a layered material with monoclinic crystal structure, has recently attracted a lot of attention due to its unique physical properties and potential applications for angle-resolved photonics and electronics, where optical anisotropies are important. Despite a few reports on the in-plane anisotropies of GaTe, a comprehensive understanding of them remained unsatisfactory to date. In this work, we investigated thickness-dependent in-plane anisotropies of the 13 Raman-active modes and one Raman-inactive mode of GaTe by using angle-resolved polarized Raman spectroscopy, under both parallel and perpendicular polarization configurations in the spectral range from 20 to 300 cm-1. Raman modes of GaTe revealed distinctly different thickness-dependent anisotropies in parallel polarization configuration while nearly unchanged for the perpendicular configuration. Especially, three Ag modes at 40.2 ([Formula: see text]), 152.5 ([Formula: see text]), and 283.8 ([Formula: see text]) cm-1 exhibited an evident variation in anisotropic behavior as decreasing thickness down to 9 nm. The observed anisotropies were thoroughly explained by adopting the calculated interference effect and the semiclassical complex Raman tensor analysis.

International Price Comparisons of Anticancer Drugs: A Scheme for Improving Patient Accessibility.

BACKGROUND: The demand for implementing a new listing scheme to expedite patient access to novel oncology drugs has increased in South Korea. This study was conducted to compare the prices of anticancer drugs between eight countries and to explore the feasibility of a 'pre-listing and post-evaluation' scheme to expedite patient access to oncology drugs. METHODS: This study included 34 anticancer drugs, which were reimbursed between 1 January 2007 and 31 December 2017. The unit price and sales volume of the study drugs were collected from eight countries and IQVIA data, respectively. The prices were adjusted to estimate the ex-factory prices using the discount/rebate rate suggested by the Health Insurance Review Agency (HIRA). The four price indices of Laspeyres, Paasche, Fisher, and the unweighted index were calculated using the price in each country, the average price, and lowest price among the study countries. Each currency was converted using the currency exchange rate and purchasing power parity (PPP). The budget impact of implementing the proposed pre-listing and post-evaluation scheme on payers was calculated. RESULTS: Based on the currency exchange rate, anticancer drug prices were higher in other countries (index range: 1.05-2.78) compared to Korea. The prices in Korea were similar to countries with the lowest prices. When the PPP was applied, prices were higher in the US, Germany, Italy, and Japan than in Korea (range: 1.10-2.13); however, the prices were lower in the UK, France, and Switzerland than in Korea (range: 0.72-0.99). The financial burden of implementing the pre-listing and post-evaluation scheme was calculated at 0.83% of the total anticancer drug sales value in Korea from 2013-2017. CONCLUSIONS: The prices of anticancer drugs in Korea were similar to the lowest prices among the seven other study countries. A pre-listing and post-evaluation scheme should be considered to improve patient access to novel anticancer drugs by reducing the reimbursement review time and uncertainties.

Bias-controlled multi-functional transport properties of InSe/BP van der Waals heterostructures.

Van der Waals (vdW) heterostructures, consisting of a variety of low-dimensional materials, have great potential use in the design of a wide range of functional devices thanks to their atomically thin body and strong electrostatic tunability. Here, we demonstrate multi-functional indium selenide (InSe)/black phosphorous (BP) heterostructures encapsulated by hexagonal boron nitride. At a positive drain bias (VD), applied on the BP while the InSe is grounded, our heterostructures show an intermediate gate voltage (VBG) regime where the current hardly changes, working as a ternary transistor. By contrast, at a negative VD, the device shows strong negative differential transconductance characteristics; the peak current increases up to ~5 µA and the peak-to-valley current ratio reaches 1600 at VD = -2 V. Four-terminal measurements were performed on each layer, allowing us to separate the contributions of contact resistances and channel resistance. Moreover, multiple devices with different device structures and contacts were investigated, providing insight into the operation principle and performance optimization. We systematically investigated the influence of contact resistances, heterojunction resistance, channel resistance, and the thickness of BP on the detailed operational characteristics at different VD and VBG regimes.

Selective Growth and Robust Valley Polarization of Bilayer 3R-MoS2.

Noncentrosymmetric transition-metal dichalcogenides, particularly their 3R polymorphs, provide a robust setting for valleytronics. Here, we report on the selective growth of monolayers and bilayers of MoS2, which were acquired from two closely but differently oriented substrates in a chemical vapor deposition reactor. It turns out that as-grown bilayers are predominantly 3R-type, not more common 2H-type, as verified by microscopic and spectroscopic characterization. As expected, the 3R bilayer showed a significantly higher valley polarization compared with the centrosymmetric 2H bilayer, which undergoes efficient interlayer scattering across contrasting valleys because of their vertical alignment of the K and K' points in momentum space. Interestingly, the 3R bilayer showed even higher valley polarization compared with the monolayer counterpart. Moreover, the 3R bilayer reasonably maintained its valley efficiency over a very wide range of excitation power density from ∼0.16 kW/cm2 to ∼0.16 MW/cm2 at both low and room temperatures. These observations are rather surprising because valley dephasing could be more efficient in the bilayer via both interlayer and intralayer scatterings, whereas only intralayer scattering is allowed in the monolayer. The improved valley polarization of the 3R bilayer can be attributed to its indirect-gap nature, where valley-polarized excitons can relax into the valley-insensitive band edge, which otherwise scatter into the contrasting valley to effectively cancel out the initial valley polarization. Our results provide a facile route for the growth of 3R-MoS2 bilayers that could be utilized as a platform for advancing valleytronics.