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Based on the results of international multicenter randomized trials, completion lymph node dissection for patients with sentinel lymph node-positive melanoma is no longer routinely recommended. However, clinicians should take into consideration racial and medical resource differences when applying this evidence to clinical practice in Japan. To evaluate the clinical validity of the observation policy of omitting completion lymph node dissection, we retrospectively surveyed patients with sentinel lymph node-positive melanoma between 2002 and 2020 at Niigata Cancer Center Hospital. A total of 59 patients were categorized into the observation group (n = 19) and completion lymph node dissection group (n = 40). Newly developed anticancer agents, including targeted therapy and immunotherapy, were more commonly used in the observation group than in the completion lymph node dissection group as either adjuvant therapy (31.6% vs. 5.0%) or post-recurrence therapy (100% vs. 34.8%). The median overall survival in the observation group (not reached) was significantly longer than that in the completion lymph node dissection group (95.0 months; p = 0.02), which was mainly attributed to the difference in post-recurrence overall survival. There was no significant difference in recurrence-free survival between the two groups (p = 0.63). Although the use of new anticancer agents leads to bias, this study demonstrates that observation without prompt completion lymph node dissection provides a favorable overall survival without increasing the risk of recurrence compared with completion lymph node dissection. The observation policy for patients with sentinel lymph node-positive melanoma patients is considered to be clinically valid in real-world medical practice.

Basal cell carcinoma is the most common type of skin cancer, and surgical excision with clear margins is the standard of care. Surgical margins are determined based on risk factors (high or low risk) for recurrence according to the National Comprehensive Cancer Network and Japanese basal cell carcinoma guidelines. The clarity of the clinical tumor border (well-defined or poorly defined) is considered a risk factor, and significant discrepancies in the judgment of clinical tumor borders among dermato-oncologists may occur. Therefore, we analyzed the dermato-oncologists' concordance in judging the clinical tumor border of basal cell carcinoma. Forty-seven dermato-oncologists (experts: 37; young trainees: 10) participated in this study. The datasets of clinical and dermoscopic photographs of 79 Japanese cases of head and neck basal cell carcinoma were used to determine the concordance in the judgment of clinical tumor border. The probability of the border that was selected more often was used to calculate the rater agreement rate for each dataset. Correct judgment was defined as a more frequently selected border, and the concordance rate of clarity of clinical tumor border for each dermato-oncologist was calculated based on the definition of the correct judgment. A median concordance rate of 85% or higher for all dermato-oncologists was predefined as an acceptable rate for clinical use. Of the 79 datasets, rater agreement rates were 80-100%, 60-79%, and 51-59% for 55, 19, and five datasets, respectively. The median concordance rate for all dermato-oncologists was 86% (interquartile range: 82-89%). There was no significant difference in the concordance rate between the experts and the trainees (median, 87% vs. 85.5%; p = 0.58). The concordance rates of dermato-oncologists for all datasets were relatively high and acceptable for clinical use.

The incidence of skin cancers is on the rise due to population growth and aging.1 The eyelid region is one of the common sites for skin cancers, the majority of which are basal cell carcinoma, followed by squamous cell carcinoma and sebaceous carcinoma.2 Of note, the lower eyelid is more prone to be affected by skin cancers. The eyelid is composed of anterior and posterior lamellae, and when full-thickness lower eyelid defects cannot be directly closed, reconstruction of both the posterior and anterior lamellae, along with tarsal plate replacement, are typically performed.3 However, elderly patients with skin cancer may not be amenable to such extensive surgery. Between 1997 and 2019 at our hospital, 5 patients underwent successful reconstruction of full-thickness lower eyelid defects with the repair of only the anterior lamella while allowing the posterior lamellar portion to heal secondarily. We herein report one representative case. In addition, we discuss the clinical validity of less extensive surgery for elderly patients by allowing the posterior lamellar portions of lower eyelid defects to heal secondarily.

As cancer treatment advances, the need for dermatologists in the treatment process is increasing. Cancer patients often experience cutaneous manifestations of internal diseases and dermatological adverse events from chemotherapy, radiation, surgery, and stem cell transplants. These diminish patients' health-related quality of life and negatively affect cancer treatment adherence. To identify the dermatologist's role, we analyzed 893 cases of in-hospital dermatology consultations at the Niigata Cancer Center Hospital during 2019. The number of dermatology consultations was the second highest among all hospital departments. Malignant tumors accounted for 91.7% of the underlying diseases, including hematological, gastrointestinal, and lung cancer as the top three primary cancers. The most common consultation category was inflammatory skin disorders (29.2%), followed by chemotherapy-related skin disorders (23.5%), cutaneous infections (11.5%), skin tumors (9.5%), and continued treatment of pre-existing skin disorders (8.8%). The average intervention time was the longest for continued treatment of existing skin disorders (229 ± 60.6 days), followed by malignant wound management (126 ± 60.6 days) and chemotherapy-related skin disorders (122 ± 60.6 days). The median overall survival time of the 27 patients in the malignant wound management group was 5 months (95% confidence interval, 1.8-8.2 months) from the initial dermatology consultation. Our results show an increasing demand for dermatologists in cancer management. However, the number of full-time dermatologists is insufficient in some Japanese cancer hospitals. There is a need to consider increasing the number of adequately trained dermatologists in cancer medical settings.

Hailey-Hailey disease (HHD) is an autosomal dominant genetic disease caused by a mutation of the ATP2C1 gene. Corticosteroids, antibiotics or cyclosporine have been administered to reduce inflammation and prevent flare-ups, but the efficacy is not always sufficient. We herein report two cases of HHD effectively treated with apremilast and review the previous literature. Patient 1 was a 28-year-old male and patient 2 was a 35-year-old female. Both patients were diagnosed with HHD based on histological and genetic analyses. Both patients were treated with oral antibiotics or topical corticosteroids, but their symptoms were refractory, therefore apremilast was administered to both patients. Two weeks later, the skin lesion of both patients was improved. No adverse reaction was observed except for mild headache in patient 2. There have been 13 reported cases of HHD treated with apremilast, including our cases. Eight cases showed a good response to apremilast, whereas five cases showed no response. There seems to be no association between the disease severity and efficacy of apremilast, although the reason remains unknown. Interestingly, an early improvement of the HHD lesion was observed in all good response cases. Although digestive symptoms, headache, and myalgia were observed as adverse events, the treatment was well-tolerated. The accumulation of a greater number of similar cases and further research will be required. We hypothesize that apremilast may be a useful therapeutic option for skin lesions of HHD.

An 81-year-old man presented to our hospital for the evaluation of two tumors located on a burn scar at his right temple. The patient had suffered a thermal burn to his temple from a hearth at one year old. One year before his consultation, two tumors simultaneously developed and had progressively grown. The tumors were surgically resected with margins; thereafter, full thickness skin grafting was performed. A histological examination revealed that the tumors were histologically squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). The patient is now being carefully observed. SCC is a malignant tumor that originates from epidermal keratinocytes and occasionally develops from burn scars. In post-burned lesions, scars or any other chronic wound, malignant degeneration typically ensues over a period of time. Skin cancers that develop from burn scars are considered more aggressive than other types of skin cancer and showed higher rates of regional metastasis and mortality. BCC is the most common skin malignancy and arises from basal keratinocytes of the interfollicular epidermis or hair follicle; burn scars are rarely associated with it. To our knowledge, there have been very few case reports published concerning burn scar carcinomas comprising both SCC and BCC. We herein report a unique case in which SCC and BCC co-existed within a single burn scar region on the temple with a review of the literature concerning burn scar carcinogenesis. Keywords: Squamous cell carcinoma, Basal cell carcinoma, Burn scar carcinoma, Tumorigenesis

Herein, a photocatalytic Giese-type reaction with alkylsilicates bearing C,O-bidentate ligands as stable alkyl radical precursors has been reported. The alkylsilicates were prepared in one step from organometallic reagents. Not only primary, secondary, and tertiary alkyl radicals, but also elusive methyl radicals, could be generated by using the present reaction system. The generated radicals were trapped by electron-deficient olefins bearing various functional groups to give the desired alkyl adducts. The silicon byproduct can be recovered after the photoreaction. The radical generation process was investigated by theoretical calculations, which provided an insight into the facile generation of methyl radicals from methylsilicate bearing C,O-bidentate ligands.

Advances in anticancer therapy, including the development of targeted therapy and immunotherapy, have drastically changed treatment options for metastatic melanoma. However, to date, only a few studies have been published that directly compare overall survival (OS) before and after introduction of these new therapeutic options in Japan. We retrospectively surveyed patients with metastatic melanoma treated in our hospital between 1989 and 2019 to investigate the OS benefit of the new therapies. A total of 115 patients with metastatic melanoma (cutaneous origin, 92; mucosal, 14; uveal, two) were included in the study. Kaplan-Meier analysis showed that the patient group receiving targeted therapy/immunotherapy (TT/IT) (n = 47) had a median OS of 19.0 months, which was longer than that in patients receiving conventional chemotherapy (n = 42, 8.0 months) or no treatment (n = 26, 6.0 months) (P < 0.001). In the subgroup analysis performed for the TT/IT group, patients of younger age and with the BRAF mutation had significantly improved OS. As the number of treatment lines increased, the median OS tended to become longer. Our real-world data confirmed an improvement of median OS upon the introduction of the new therapies for metastatic melanoma. However, the long-term OS benefit was limited, possibly because of racial differences in some of the clinical characteristics. To improve the overall melanoma prognosis, the entire treatment strategy, including perioperative therapy needs strengthening.

The correlation of the chemical composition, the structure, and the microwave characteristic of solid solutions of the BaFe12 – xDxO19 (0.1 ≤ x ≤ 1.2) barium hexaferrite substituted with diamagnetic Al3+ and In3+ ions has been studied. The precise data on the crystal structure have been obtained by powder neutron diffraction using a high-resolution Fourier diffractometer (Dubna, JINR). The data on the distribution of the diamagnetic substituting ions in the hexaferrite structure have been obtained by Mossbauer spectroscopy. The microwave properties (the transmittance and the reflectance) have been studied in the frequency range 20–65 GHz and in external magnetic fields to 8 kOe. It is found that the transmission spectra are characterized by a peak that corresponds to the resonant frequency of the electromagnetic energy absorption, which is due to the ferromagnetic resonance phenomenon. The correlation of the chemical composition, the features of the ion distribution in the structure, and the electromagnetic properties has been revealed. It is shown that external magnetic fields shift the absorption peak of electromagnetic radiation to higher frequencies due to an increase in the magnetocrystal anisotropy. The results enable the conclusion that the features of the intrasublattice interactions and the electromagnetic properties should be explained using the phenomenological Goodenough–Kanamori model.

The kinetics of impregnation of graphite surface by water-salt solutions has been described theoretically. This process for the indicated group of carbon materials was shown to be of diffusive character. The equation to estimate the time of graphite materials impregnation by water-salt solutions has been derived. This parameter was shown to be determined by the state of surface, geometry structure of pores, type of salt, and its solution concentration as well as by the parameters of air diffusion through salt solution. The process of salt crystallization on the surface of graphite materials has been analyzed theoretically. The equilibrium value of wetting angle (i.e., the state of graphite surface) was revealed to be the main parameter determining this process. The dependence between part of crystalline salt phase on the surface of graphite material and wetting angle has been derived. The chemical activation of graphite material surface results in the reducing of wetting angle and, respectively, to the increasing of the part of crystalline salt phase was shown.

An effective permittivity of polymer composites (CMs) with randomly distributed electroconductive and dielectric nanoparticles was considered within the Maxwell-Garnett (MG) model. The modeling of effective permittivity showed that the content and parameters of conductive filler particles affect the value and frequency dependence of permittivity of CMs. It was found that at equal parameters of electroconductive inclusions in CMs such as aspect ratio (AR), electrical conductivity, and content (lower than the percolation threshold), the use of 1D (carbon nanotubes CNT) particles as filler leads to sufficiently higher values of real and imaginary parts of permittivity and shifts the maximum of dielectric loss into lower frequency range of electromagnetic radiation (EMR) compared with 2D (graphite nanoplatelets GNP) filler particles. The use of mixed 1D/2D conductive filler allows extending the frequency range of dielectric loss in CMs varying the aspect ratio and electrical conductivity of fillers. The addition of spherical highly dielectric disperse particles (e.g., BaTiO3 at content in 10 vol.%) into CMs with 1D (or 2D) conductive filler slightly increases permittivity, however, increases the percolation threshold, so the larger number of conductive particles may be inserted into polymer matrix before percolation and higher permittivity may be achieved. The increase of content and aspect ratio of BT particles in three-phase carbon/BaTiO3/polymer composites may result in sufficient increase of permittivity.

The crystal structure of solid solutions of an M-type hexagonal barium ferrite BaFe1–x Ga x O19 (x = 0.1–1.2) with the isostructural diamagnetic substitution of Ga3+ ions has been studied by X-ray diffraction. The unit cell parameters have been calculated for all compositions. The field and temperature dependences of the specific magnetization of these solid solutions have been measured by vibrational magnetometry. The microwave properties of BaFe12–x Ga x O19 (x = 0.1–1.2) have been studied in a bias field. It has been shown that the frequency of natural ferromagnetic resonance decreases as the Ga concentration increases from x = 0.1 to x = 0.6 and it increases once again as the Ga concentration increases to x = 1.2. As the Ga concentration increases, the natural ferromagnetic resonance lines broaden. This indicates an increase in the frequency range of strong absorption of electromagnetic radiation. In this case, the amplitude of the resonance curve peak changes insignificantly. The frequency shift of the natural ferromagnetic resonance in an external magnetic field increases as the gallium ion concentration in the sample decreases.

X-ray powder diffraction is used to determine the unit cell parameters and to refine the crystal structure of the solid solutions of M-type hexagonal barium ferrite BaFe12–x Ga x O19 (x = 0.1–1.2) with isostructural diamagnetic cation Ga3+ substitution at T = 300 K. As the level of substitution increases, the unit cell parameters are shown to decrease monotonically. The temperature (300 K ≤ T ≤ 750 K, H = 8.6 kOe) and field (T = 300 K,–20 kOe ≤ H ≤ 20 kOe) dependences of the saturation magnetization of these solid solutions are studied with a vibrating-sample magnetometer. The concentration dependences of the Curie temperature T C, the specific spontaneous magnetization, and the coercive force are plotted. The magnetic parameters are found to decrease with increasing substitution. The microwave properties of the solid solutions are analyzed in an external magnetic field (0 ≤ H ≤ 4 kOe). As the cation Ga3+ concentration increases from x = 0.1 to 0.6, the natural ferromagnetic resonance (NFMR) frequency decreases; as the concentration increases further to x = 1.2, this frequency again increases. As the cation Ga3+ concentration increases, the NFMR line width increases, which indicates a widening of the frequency range where electromagnetic radiation is intensely absorbed. Here, the resonance curve peak amplitude changes insignificantly. The shift of the NFMR frequency in an applied magnetic field is more pronounced for samples with low cation Ga3+ concentrations. The role of diamagnetic substitution is revealed, and the prospects and advantages of Ga-substituted beryllium hexaferrite as the material absorbing high-frequency electromagnetic radiation are demonstrated.

The purpose of this study is to investigate the origin of nitride inclusions in the aluminum casting process. The authors surveyed the behavior of aluminum and magnesium under several environmental conditions. The results showed that the oxidation and nitridation reactions during the melting process are key factors for producing nitride inclusions. The authors determined the forming conditions of AlN and Mg3N2, and established a method of producing them in liquid aluminum. Additionally, the standard Gibbs free energies of formation of several oxides and nitrides were calculated. The experimental results were consistent with the thermodynamic stability. The method of preventing the formation of nitride inclusions was both experimentally and theoretically derived.

Suzuki coupling reactions are performed using PdO loaded on dealuminated Y (USY) zeolite. The reaction between bromobenzene and phenylboronic acid is complete in 15 min at room temperature in air, with a turnover number of 1300. The reaction can be repeated at least five times by using 1 wt % Pd. Inductively coupled plasma analysis does not reveal the dissolution of Pd from products, even if the reaction is repeated up to four times. Pd K-edge extended X-ray absorption fine structure analysis reveals the presence of molecular-like PdO and a mixture of Pd(0) -PdO before and after the reaction, respectively. This is probably because Pd stabilized by Al sites is present at the II sites of the Y-type zeolite, as estimated using first-principles calculations. Conversely, Pd species change to PdO clusters after repeated reactions in air using the thermally treated sample.

The processes of formation of nanostructured metals phases on the surface of graphites with different structure and surface morphology (thermoexfoliated graphite, dispersion graphite) are considered. Substrates of graphite carriers of different structural types differ in characteristics of the surface condition. The thermoexfoliated graphite has the most developed, porous and defective surface. Further in this series there is dispersed graphite with a chemically activated by acid surface and the least developed and defective structure of the surface is determined for dispersion graphite. A generalized model of the processes occurring in the formation of nanostructured forms of metal on the surface of a graphite carrier is proposed, which is based on description of the common positions of topographic reactions of all stages of the formation of a metal component — crystallization of salt, salt thermolysis on a surface of a graphite carrier, reaction of oxide recovery to pure metal. For each stage of the process function is introduced that determines the dependence of the emergence of certain mass of the new phase on the unit surface of the substrate. The evolution of this function from time to time is described by the system of differential equations, taking into account that each subsequent stage proceeds independently of the previous one at a certain time, and is related to the previous mass only of the new phase obtained at this stage. The generalized model of the processes occurring in the formation of nanostructured forms of metal on the surface of a graphite carrier, constructed from unified positions, allows us to model and describe each stage of this process using different types of graphite materials, different salts and conditions of each stage.

The purpose of this study is to investigate the effect of adding the Al–Ti–B grain refiner to the aluminum twin roll casting. The authors analyzed the microstructure of the as-cast strip produced by the twin roll casting based on several casting conditions. The results showed that the amount of the TiB2 particles and the temperature gradient in the solidification area are the key factors for enhancing the effect of the grain refining. Additionally, this study simulated the behavior of the TiB2 particles in the aluminum melt. The temperature distribution of the aluminum between the twin rolls was also calculated. The authors clarified the relationship between the grain refiner particles and the temperature gradient for the grain refining effect during the twin roll casting.

The influence of CO2 in the oxidant gas on the cell performance of anion-exchange membrane fuel cells was investigated using a three-electrode single cell with a reversible hydrogen electrode (RHE). The overpotential of the cathode was hardly changed by the presence of CO2, while the overpotential of the anode increased after the introduction of CO2 at the cathode. The high anode overpotential was caused by a high CO32- concentration in the anode catalyst layer, even when most of the CO32- ions in the electrolyte membrane are purged during operation through the self-purging mechanism.

A model based on discrete element method has been developed for the interaction between wet cohesive granular materials and mechanical tools with complex geometry. To obtain realistic results, the motion of 52.5 million particles has been simulated and the formation of multiple shear bands during an excavation process by a bulldozer blade was observed.

Making digital games can help people learn collaboratively. Recent advances in game education allow for experimental game development in a short time period with low cost. To examine the possibilities of game development and learning, we focus on the recent "game jam" approach in collaborative game development. The concept of game jam becomes well-known these days, however, its historical development, goals, and strategies have not yet been explored. To bring game jam into the education and learning, we first look at its historical development and key concept referencing Global Game Jam, the biggest annual game jam in the world, and then we discuss the recent case of "localized" Global Game Jam---style events embedded in the social context of a specific region.

The effects of CO2 on the performance of an anion-exchange membrane fuel cell were investigated using a three-electrode single cell equipped with a reference electrode. Though the membrane resistance decreased at high current densities in the presence of CO2 via the self-purging mechanism, the cell voltage was significantly lower than that for pure O2 especially at low current densities even at a very low CO2 concentration of 100 ppm. The overpotential at the cathode was hardly changed by the presence of CO2, while that at the anode significantly increased in the presence of CO2. It was concluded that carbonate/bicarbonate ions accumulated at the anode during operation, and reduces the ionic conductivity and the pH in the anode catalyst layer, which results in a high overpotential at the anode.