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Introduction: In Japan, endometrial cytology is widely performed to evaluate the status of the endometrium in women with suspected endometrial cancer. A new classification system for endometrial cytology has recently been used: the Yokohama system, based on a descriptive reporting format. This study aimed to clarify the triage for patients with atypical endometrial cells of undetermined significance (ATEC-US) when followed by negative endometrial cytology. Methods: We enrolled patients diagnosed with ATEC-US at the Cancer Institute Hospital between January 2016 and December 2017, based on the following inclusion criteria: (1) ATEC-US diagnosed by office endometrial cytology, with or without office endometrial biopsy; (2) follow-up endometrial cytology was performed 3–6 months after initial sampling, with a negative result for malignancy; and (3) no prior history of conservative treatment with progestin for endometrial cancer or atypical endometrial hyperplasia (ATEC-A). Among eligible patients, we analyzed those later diagnosed by endometrial biopsy with ATEC-A or carcinoma. Results: Among 187 patients, 65 met the inclusion criteria. Forty-two patients (64.6%) were observed for more than 24 months. Two patients (3.1%) developed ATEC-A during a median observation time of 26.5 months; the times to diagnosis were 32 months and 22 months. Discussion/Conclusion: No patient developed ATEC-A or worse within 1 year. For patients with ATEC-US, if negative cytology is obtained at the next examination, a close follow-up is not necessary.

A 56-year-old man presented with fever, cough, and bloody sputum. He had undergone mitral valve replacement with mechanical prosthesis 14 months prior for mitral valve disease. Subsequently, the patient was taking warfarin and amiodarone. Chest imaging revealed dense, infiltrative shadows, and blood tests showed prolonged prothrombin time and eosinophilia. Warfarin was withdrawn, and antibiotics were started, but bloody sputum and respiratory failure persisted. Considering that eosinophilia was observed after the administration of amiodarone, the drug was discontinued, and bronchoalveolar lavage was performed. Cytology showed foam cells, eosinophils, and hemosiderin-laden macrophages; amiodarone-induced diffuse alveolar hemorrhage (DAH) and acute eosinophilic pneumonia (AEP) were diagnosed, and the patient was treated with corticosteroids. This report describes the first documented case of amiodarone-induced DAH and AEP. When a patient taking amiodarone presents with antibiotic-refractory pneumonia with bloody sputum and eosinophilia, amiodarone-induced DAH and AEP should be considered. LEARNING OBJECTIVE: We report the first case of amiodarone-induced diffuse alveolar hemorrhage (DAH) and acute eosinophilic pneumonia (AEP) diagnosed by foam cells, eosinophils, and hemosiderin-laden macrophages on bronchoalveolar lavage cytology. When a patient taking amiodarone presents with antibiotic-refractory pneumonia with bloody sputum and eosinophilia, amiodarone-induced DAH and AEP should be considered.

Aim Extended-field concurrent chemoradiation therapy (Ex-CCRT) has been widely used for para-aortic lymph node (PAN) metastases confirmed by radiographic assessment without surgical exploration. The objective of this prospective study was to evaluate the clinical value of laparoscopic retroperitoneal PAN biopsy in locally advanced cervical cancer (LACC) with pelvic lymph node (PLN) metastases. Methods From May 2017 to March 2020, stage IIB-IIIB cervical cancer patients who were diagnosed with PLN metastasis using positron emission tomography-computed tomography (PET-CT) with maximum standardized uptake value (SUVmax) ≥2.0 underwent laparoscopic retroperitoneal PAN biopsy. The radiation fields were extended to PAN areas with pathological metastases. Results Fourteen patients were diagnosed with cervical squamous cell carcinoma of the International Federation of Gynecology and Obstetrics (FIGO) stage IIB (n = 7) and IIIB (n = 7). The median operating time was 138 min (range, 104-184 min). The median number of harvested PANs was 19 (range, 6-36). Three patients were positive for PAN metastasis on histological analysis. In this study, the sensitivity and specificity of PET-CT were 66.7% and 90.9%, respectively. Conclusion Our study is characterized by the use of more appropriate eligibility criteria for LACC with PLN metastases. Our results revealed that laparoscopic retroperitoneal PAN biopsy may be a useful approach to determine the radiation field for PANs during standard radiotherapy planning.

Background To determine the impact of the coverage of risk-reducing salpingo-oophorectomy (RRSO) and mastectomy (RRM) as well as genetic testing for BRCA pathogenic variants by the national insurance system in Japan. Methods We compared the clinical background of women who underwent RRSO at our institution before and after its coverage by the national insurance system. Results Those who underwent RRSO between January 2017 and December 2019 and between April 2020 and March 2022 were classified as Period A and B, respectively. Overall, 134 women underwent RRSO during the study period. In Period A and B, 45 and 89 women underwent RRSO for the study period was 36 and 24 months, respectively. Compared with Period A, the number of women who underwent RRSO per month increased by 3-fold in Period B (p < 0.01). In addition, the number of women who underwent surgery for breast cancer along with RRSO increased in Period B (p < 0.01). Although the number of women who underwent concurrent RRM with RRSO in Period B increased, the difference was not statistically significant. Compared with Period A, the number of women diagnosed with BRCA pathogenic variant increased by 3.9-fold, and the proportion of women who underwent concurrent hysterectomy at the time of RRSO decreased from 66% to 7.9% in Period B (p < 0.01). Conclusion Owing to the introduction of the national insurance system, the number of women who underwent RRSO and concurrent surgery for breast cancer at the time of RRSO increased in Japan.

Obturator nerve injury is an uncommon complication frequently associated with pelvic gynecologic or urologic cancer surgery. It can lead to disability or adversely affect quality of life. Large segmental defects are particularly difficult to manage as the limited mobility of the nerve prevents tension-free direct end-to-end anastomosis. A 36-year-old woman with cervical cancer underwent sentinel lymph node biopsy, laparoscopic radical hysterectomy, and bilateral adnexectomy. During the procedure, the sentinel lymph node (right obturator node) adherent to the obturator nerve was resected together with the nerve segment leaving a 3 cm defect. Immediate laparoscopic obturator nerve repair was performed using an artificial nerve conduit leading to successful recovery. We report this unique case due to rarity of large segmental obturator nerve defects and present laparoscopic nerve repair with artificial nerve conduits as a useful treatment alternative of these important injuries, without nerve donor site morbidity.

Constructing synthetic models of the nitrogenase PN -cluster has been a long-standing synthetic challenge. Here, we report an optimal nitrogenase PN -cluster model [{(TbtS)(OEt2 )Fe4 S3 }2 (μ-STbt)2 (μ6 -S)] (2) [Tbt=2,4,6-tris{bis(trimethylsilyl)methyl}phenyl] that is the closest synthetic mimic constructed to date. Of note is that two thiolate ligands and one hexacoordinated sulfide are connecting the two Fe4 S3 incomplete cubanes similar to the native PN -cluster, which has never been achieved. Cluster 2 has been characterized by X-ray crystallography and relevant physico-chemical methods. The variable temperature magnetic moments of 2 indicate a singlet ground state (S=0). The Mossbauer spectrum of 2 exhibits two doublets with an intensity ratio of 3:1, which suggests the presence of two types of iron sites. The synthetic pathway of the cluster 2 could indicate the native PN -cluster maturation process as it has been achieved from the Fe4 S4 cubane Fe4 S4 (STbt)4 (1).

The purpose of this study was to describe how Japanese undergraduate students engage in learning in a physical activity basic instruction course, specifically, flag football. The study was situated...

An earthquake with a magnitude of 8 or 9 is predicted to occur near the Ryukyu Islands in Japan, for which the Okinawa Prefecture is preparing countermeasures. Evacuating people to a safe shelter within the tsunami arrival time is a crucial countermeasure. This study aims to understand the vulnerabilities of patients with chronic respiratory diseases in southern parts of Okinawa during a tsunami evacuation, thereby calculating evacuation distance of vulnerable patients and creating individual evacuation plans. Data for chronic respiratory patients obtained in July 2021 from the hospitals in Okinawa Prefecture include age, gender, diagnosis, residence, nearest tsunami shelter, oxygen flow at rest and walking, and maximum walking distance for 6 min based on a 6-min walk test. A quantum geographic information system was used for mapping the data. The survival potential of patients with chronic respiratory disease was evaluated by using a tsunami inundation depth of one meter and the distance within which an evacuation can be performed until the first tsunami wave reaches the nearest evacuation shelter. Results revealed a low survival potential for respiratory disease patients under the current tsunami evacuation plan. The study suggests creating an individual evacuation plan for vulnerable patients involving families and medical staff and then conducting a drill for improving the plan.

The purpose of this study was to describe and explain American undergraduate students’ social experiences interacting with non-native English-speaking Chinese international students during conversational practices at an American university. This study used an explanatory (holistic) multiple case study design (Yin, 2003) using in-depth, semistructured interviews grounded in the social exchange theory. The participants were seven American students (three men and four women) who served as conversation partners of Chinese international exchange students during each fall semester. Three major interrelated and complex themes emerged from the data. They were (a) developing social reward relationships, (b) proving the social norm information during the conversational partnerships, and (c) employing/utilizing strategies for developing trust relationships. The results of this study can be utilized to encourage faculty, global education office staff, and all students to respect, value, and embrace the languages and cultures of Chinese international students. This contribution can prompt a greater appreciation for diversity which leads to meaningful academic, athletic, and social experiences for all students at American college and university.

The purpose of this study was to extract current issues associated with the understanding of tackling techniques taught by college football coaches in Japan. The goal was to acquire fundamental information for a coaching method that would promote safe and effective tackling techniques. A total of 99 college football coaches from Japan (mean age 36.7±0.5 years) took part in the study. A questionnaire was conducted in order to understand key points that were considered important in their coaching methods. The results and observations can be summarized as follows. 1. Tackling techniques taught by football coaches in Japan often lead to concussions. This is due to coaching methods that focus heavily on tackling techniques with high concussion risks, and placing no importance on HUT-based tackling. In addition, their understanding of the “Hit” phase and “HUT” varies, leading to a greater possibility of teaching tackling with a high risk of concussion. 2. Regardless of factors such as age, the position taken as an active player, the instructor’s income, and coaching qualifications, coaches who do not have much player or coach experience have an increased tendency to teach tackling techniques associated with high risks of concussion and injury. 3. In order to prevent concussions and promote safer tackling coaching in Japan, it is crucial for coaches who have little experience in playing or coaching to have access to appropriate information and education opportunities, and for coach certification programs to be improved.

Constructing synthetic models of the nitrogenase P

Backgroud: Extended-field concurrent chemoradiation therapy (Ex-CCRT) is widely used for para-aortic lymph node (PAN) metastasis confirmed by radiographic assessment without surgical assessment. The objective of this prospective study was to evaluate the clinical value of laparoscopic retroperitoneal PAN biopsy in locally advanced cervical cancer (LACC) with pelvic lymph node metastases.Methods: From May 2017 to March 2020, patients with stage IIB-IIIB cervical cancer, who were diagnosed with pelvic node metastasis using positron emission tomography-computed tomography (PET-CT) with SUVmax ≥ 2.0, underwent laparoscopic retroperitoneal PAN biopsy. The radiation fields were extended to the PAN area with pathological metastases.Results: Fourteen patients were diagnosed with squamous cell carcinoma of the cervix at FIGO stage IIB (n=7) and IIIB (n=7). The median operating time was 138 (range, 104–184) minutes. The median number of harvested PANs was 19 (range, 6–36). Three patients were diagnosed as positive for PAN metastasis by histological analysis. In this study, the sensitivity and specificity of PET-CT were 66.7% and 90.9%, respectively.Conclisions: The results of this study revealed that laparoscopic retroperitoneal PAN should be the standard treatment method worldwide because it is not appropriate to determine the radiation field of PAN by image examination without performing a histological assessment.

The purpose of this study was to investigate five Japanese graduate (master's level) students’ experiences in online courses in international development and peace through sport that used English as the medium of instruction. The study was situated in the framework of andragogy theory and used a descriptive-qualitative design using an in-depth, semistructured interview approach using online oral and written interviews. Three emergent themes were established. These recurrent themes were (a) learning online specialized content using English as a second language, (b) students’ struggles in group projects through online education, and (c) students’ opinions about the improvement of online education. To better support Japanese graduate students’ online learning, this study encourages academic departments, administrators, and faculty to better design appropriate courses and online activities. This will contribute to a greater appreciation for the richness of sports development and peace and to increasing the availability of meaningful academic and social experiences for graduate students at Japanese universities.

An unprecedented, super oxidized all-ferric iron-sulfur cubanoid cluster with all terminal thiolates, Fe4 S4 (STbt)4 (3) [Tbt=2,4,6-tris{bis(trimethylsilyl)methyl}phenyl], has been isolated from the reaction of the bis-thiolate complex Fe(STbt)2 (2) with elemental sulfur. This cluster 3 has been characterized by X-ray crystallography, zero-field 57 Fe Mossbauer spectroscopy, cyclic voltammetry, and other relevant physico-chemical methods. Based on all the data, the electronic ground state of the cluster has been assigned to be Stot =0.

Background and Purpose— Endovascular therapy is effective against acute cerebral large vessel occlusion (LVO). However, many patients do not receive such interventions because of the lack of timely identification of the type of stroke. If the types of stroke (any stroke, LVO, intracranial hemorrhage [ICH], and subarachnoid hemorrhage [SAH]) were to be predicted at the prehospital stage, better access to appropriate interventions would be possible. Japan Urgent Stroke Triage (JUST) score was clinical prediction rule to classify suspected patients of acute stroke into different types at the prehospital stage. Methods— We obtained information for signs and symptoms and medical history of consecutive suspected patients of acute stroke at prehospital stage from paramedics and final diagnosis from the receiving hospital. We constructed derivation cohort in the historical multicenter cohort study from June 2015 to March 2016 and validation cohort in the prospective multicenter cohort study from August 2016 to July 2017. The derivation and the validation cohorts included 1229 and 1007 patients, respectively. We constructed multivariate logistic regression models with 21 variables to develop clinical prediction rules, which distinguish between different types of stroke: any stroke, LVO, ICH, and SAH. Results— Among the 1229 patients (median age, 72 years; 55% men) in the derivation cohort, 533 stroke, 104 LVO, 169 ICH, and 57 SAH cases were observed. The developed rules showed that the areas under the receiver operating curves were 0.88 for any stroke, 0.92 for LVO, 0.84 for ICH, and 0.89 for SAH. The validation cohort of 1007 patients (median age, 75 years; 56% men) showed that the areas under the curves of any stroke, LVO, ICH, and SAH were 0.80, 0.85, 0.77, and 0.94, respectively. Conclusions— These clinical prediction rules can help paramedics classify the suspected patients of stroke into any stroke, LVO, ICH, and SAH groups with excellent accuracy.

Background and Purpose— Several studies suggested that statins during hospitalization were associated with better disability outcomes in patients with acute ischemic stroke, but only 1 small randomized trial is available. Methods— We conducted a multicenter, open-label, randomized controlled trial in patients with acute ischemic strokes in 11 hospitals in Japan. Patients with acute ischemic stroke and dyslipidemia randomly received statins within 24 hours after admission in the early group or on the seventh day in the delayed group, in a 1:1 ratio. Statins were administered for 12 weeks. The primary outcome was patient disability assessed by modified Rankin Scale at 90 days. Results— A total of 257 patients were randomized and analyzed (early 131, delayed 126). At 90 days, modified Rankin Scale score distribution did not differ between groups ( P =0.68), and the adjusted common odds ratio of the early statin group was 0.84 (95% confidence interval, 0.53–1.3; P =0.46) compared with the delayed statin group. There were 3 deaths at 90 days (2 in the early group, 1 in the delayed group) because of malignancy. Ischemic stroke recurred in 9 patients (6.9%) in the early group and 5 patients (4.0%) in the delayed group. The safety profile was similar between groups. Conclusions— Our randomized trial involving patients with acute ischemic stroke and dyslipidemia did not show any superiority of early statin therapy within 24 hours of admission compared with delayed statin therapy 7 days after admission to alleviate the degree of disability at 90 days after onset. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT02549846.

Objective To evaluate the effect of dienogest (DNG) in preventing the occurrence of pain and endometriomas after laparoscopic resection of uterosacral ligaments (USLs) with deep infiltrating endometriosis (DIE). Study design This retrospective analysis included 126 patients who underwent laparoscopic resection of USLs with DIE followed by postoperative administration of DNG or no medication. Every 6 months postoperatively, patients answered questions and underwent ultrasound examination to identify pain and/or endometrioma. Result There were three (5.0%) cases of endometrioma in 59 patients from the DNG group and 21 (31.3%) cases in 67 patients from the no medication group ( P = 0.0002). Pain returned to preoperative levels in eight (11.9%) cases in the no medication group. No recurrence of pain occurred in the DNG group ( P = 0.0061). Conclusion The administration of DNG after resection of USLs with DIE significantly reduces the occurrence rate of endometriosis-related pain and endometriomas.

1 and 2 were synthesized through the complexation of 5,10,15,20-tetra-4-pyridyl-21H,23H-porphine with copper(II) acetate and copper(II) 1-naphthoate and exhibited two-dimensional open and closed form structures, respectively. X-ray diffraction identified the supramolecular interactions leading to these packing motifs. N2 and CO2 sorption isotherms indicate that 2 allows the separation of these gases.

Supplemental Digital Content is available in the text., Background and Purpose— Endovascular therapy is effective against acute cerebral large vessel occlusion (LVO). However, many patients do not receive such interventions because of the lack of timely identification of the type of stroke. If the types of stroke (any stroke, LVO, intracranial hemorrhage [ICH], and subarachnoid hemorrhage [SAH]) were to be predicted at the prehospital stage, better access to appropriate interventions would be possible. Japan Urgent Stroke Triage (JUST) score was clinical prediction rule to classify suspected patients of acute stroke into different types at the prehospital stage. Methods— We obtained information for signs and symptoms and medical history of consecutive suspected patients of acute stroke at prehospital stage from paramedics and final diagnosis from the receiving hospital. We constructed derivation cohort in the historical multicenter cohort study from June 2015 to March 2016 and validation cohort in the prospective multicenter cohort study from August 2016 to July 2017. The derivation and the validation cohorts included 1229 and 1007 patients, respectively. We constructed multivariate logistic regression models with 21 variables to develop clinical prediction rules, which distinguish between different types of stroke: any stroke, LVO, ICH, and SAH. Results— Among the 1229 patients (median age, 72 years; 55% men) in the derivation cohort, 533 stroke, 104 LVO, 169 ICH, and 57 SAH cases were observed. The developed rules showed that the areas under the receiver operating curves were 0.88 for any stroke, 0.92 for LVO, 0.84 for ICH, and 0.89 for SAH. The validation cohort of 1007 patients (median age, 75 years; 56% men) showed that the areas under the curves of any stroke, LVO, ICH, and SAH were 0.80, 0.85, 0.77, and 0.94, respectively. Conclusions— These clinical prediction rules can help paramedics classify the suspected patients of stroke into any stroke, LVO, ICH, and SAH groups with excellent accuracy.

The aim of the study was to examine the relationship between the brain natriuretic peptide (BNP) level and progression or remission of diabetic nephropathy with microalbuminuria for 3 years. The subjects were 100 Japanese type 2 diabetes mellitus outpatients with microalbuminuria. Associations between metabolic parameters at baseline [HbA1c, systolic blood pressure (SBP), urine albumin-creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and BNP] and the progression or remission of diabetic nephropathy were examined for 3 years. A total of 83 patients were examined at the end of the 3-year period, including 17 with remission to normoalbuminuria, 47 with continuing microalbuminuria, and 19 with progression to macroalbuminuria. HbA1c, ACR, and BNP differed significantly among the 3 groups (p=0.024, p

This article presents multiple potential uses of the Yakushima native cedar (Cryptomeria japonica), known in Japan as the Yaku-sugi tree. The Yaku-sugi was divided into four parts: leaves, branches with leaves, branches, and stems. We obtained the essential oil, hydrosol, distillation residue, and distillation wastewater from the trees. Essential oil and hydrosol were determined to be volatile organic compounds. All samples were screened for the following bioactivities: antioxidative, antibacterial, and anti-melanogenesis activities. Freeze-dried distillation residue was tested to assess whether it had a deodorizing effect. The main component of the leaf essential oil was found to be monoterpenes. In contrast, the stem essential oil mainly contained sesquiterpenes. In terms of bioactivities, the leaf essential oil showed antibacterial activity and the stem essential oil showed anti-melanogenesis activity. Distillation residue and wastewater showed many activities, including antioxidant, antibacterial, and...

Introduction: The effectiveness of endovascular thrombectomy for acute cerebral large vessel occlusion (LVO) was proved, but many patients did not received such interventions because capable operators were not placed at all hospitals. If the type of stroke [large vessel occlusion, subarachnoid hemorrhage (SAH), intracranial hemorrhage (ICH), other cerebral infarction (CI)] was predicted at prehospital, better access to appropriate interventions were capable. We, thus, developed the clinical prediction rules to classify the type of stroke who were suspected to suffer acute stroke at prehospital, and validated them. Methods: We analyzed consecutive 1,229 patients who were suspected to suffer acute stroke from June, 2015 to March 2016. We obtained the history and physical signs at prehospital from paramedics and final diagnosis from hospital transferred. We constructed multivariate logistic regression models for 1) LVO, 2) SAH, 3) ICH, 4) CI, and developed the clinical prediction rules for each type. We prospectively validated the rules with another consecutive patients from August 2016 to July 2017 using mobile application. Results: In the derivation cohort, 104 LVO, 57 SAH, 169 ICH, and 183 CI were observed. The area under the receiver operating curve (AUC) of the rules were 0.90 for LVO, 0.90 for SAH, 0.85 for ICH, and 0.65 for CI. The validation cohort of 932 patients showed the sensitivity and specificity of the rules were 0.53 and 0.95 for LVO, 0.73 and 0.96 for SAH, 0.52 and 0.85 for ICH, 0.63 and 0.70 for CI. The AUCs of LVO, SAH, ICH, and CI were 0.85, 0.96, 0.77, and 0.67, respectively. Conclusions: The clinical prediction rule calculated by paramedics at prehospital can easily classify the patients who suspected to have stroke into LVO, SAH, ICH, and CI with excellent performance. By applying the rules, more patients would receive appropriate interventions without unnecessary delay.

We propose an image analysis method for quality evaluation of human pluripotent stem cells based on biologically interpretable features. It is important to maintain the undifferentiated state of induced pluripotent stem cells (iPSCs) while culturing the cells during propagation. Cell culture experts visually select good quality cells exhibiting the morphological features characteristic of undifferentiated cells. Experts have empirically determined that these features comprise prominent and abundant nucleoli, less intercellular spacing, and fewer differentiating cellular nuclei. We quantified these features based on experts' visual inspection of phase contrast images of iPSCs and found that these features are effective for evaluating iPSC quality. We then developed an iPSC quality evaluation method using an image analysis technique. The method allowed accurate classification, equivalent to visual inspection by experts, of three iPSC cell lines.

[4Fe-4S] clusters modeled after those in organisms having three cysteine thiolates and one carboxylate were synthesized by using the tridentate thiolato chelate. X-ray structural analysis reveals that the carboxylates coordinate to the unique irons in an η(1) manner rather than η(2). Redox potentials show a positive shift from that of the cluster having ethanethiolate and the tridentate thiolato chelate. These properties conform to the arrangement of the [4Fe-4S] clusters in the electron transfer systems included in Rc dark operative protochlorophyllide oxidoreductase (DPOR) and formaldehyde oxidoreductase (FOR) with Pf ferredoxin.

In this study, we have numerically analyzed the transport properties of Bi-Sb nanowires, taking into account wire boundary scattering. Wire boundary scattering slightly decreased the Seebeck coefficient of Bi-Sb nanowires. This effect is due to the observation that boundary scattering and the mobility ratio of L-point electrons to T-point holes in the nanowires are smaller than those in bulk Bi-Sb because the wire boundary scattering suppresses the mobilities of L-point electrons and heavy holes. The largest Seebeck coefficient for all wire diameters was obtained when the Sb concentration was 5 at.%. The effective mass approached zero near 5 at.% Sb, and the small effective mass led to a large subband shift in each band. Thus, a small effective mass enhances the quantum effect at a fixed wire diameter, even if wire boundary scattering is taken into account.

Dissimilar metal joining of aluminium alloys to steel is generally difficult to be in practical use because of a formation of brittle intermetallic Fe–Al compound (IMC) at the interface of the joint. The authors have been researching in order to minimize the thickness of this brittle IMC in order to get excellent joint strength and have found that the formation of this brittle IMC is regionally prevented by using the advanced hot-dip aluminized steel sheet and by adopting suitable joining conditions. In particular, this paper focuses on the mechanism of creating this IMC-free region in the case of MIG-braze welding and the results obtained are as follows. (1) The creation of IMC-free region is initiated as the first process by the dissolution of the τ5 phase (Fe–Al–Si) in the aluminized layer into the weld metal, and temperatures of more than 886 K for dissolution during MIG-braze welding and the use of filler metal for dilution of Fe and Si in τ5 phase have significant effects. (2) In the second process,...

Weldability of A6082 with Nd–YAG laser was investigated to explain the advantages over the conventional MIG process. It is concluded that rapid cooling rate in heat-affected zone (HAZ) contributes to increasing joint strength and improvement durability against liquation cracking in HAZ during Nd–YAG laser welding. This is why rapid cooling rate is enough to prevent crossing the C-curve for precipitation of β′ and small volume of weld metal is enough to reduce shrinkage strain during solidification. And the joint strength increased with an increase of manganese content in the base metal, but by contraries the minimum hardness in HAZ where the fracture occurred in the tensile test decreased. This may be attributed to the prevention of intercrystalline embrittlement due to the addition of manganese in case of Al–Mg–Si series alloys with excessive Si content.

An important feature of efforts to prevent global warming is the appropriate use of aluminium to reduce the weight of motor vehicles, etc., and this necessitates the development of techniques for j...

The Ni(I) tetraazacycles [Ni(dmmtc)](+) and [Ni(mtc)](+), which have methylthioethyl pendants, were synthesized as models of the reduced state of the active site of methyl coenzyme M reductase (MCR), and their structures and redox properties were elucidated (dmmtc, 1,8-dimethyl-4,11-bis{(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane; mtc, 1,8-{bis(2-methylthio)ethyl}-1,4,8,11-tetraaza-1,4,8,11-cyclotetradecane). The intramolecular CH(3)-S bond of the thioether pendant of [Ni(I)(dmmtc)](OTf) was cleaved in THF at 75 °C in the presence of the bulky thiol DmpSH, which acts as a proton source, and methane was formed in 31% yield and a Ni(II) thiolate complex was concomitantly obtained (Dmp = 2,6-dimesityphenyl). The CH(3)-S bond cleavage of [Ni(I)(mtc)](+) also proceeded similarly, but under milder conditions probably due to the lower potential of the [Ni(I)(mtc)](+) complex. These results indicate that the robust CH(3)-S bond can be homolytically cleaved by the Ni(I) center when they are properly arranged, which highlights the significance of the F430 Ni environment in the active site of the MCR protein.