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Current dosimetry protocols specify an effective point of measurement (EPOM) shift of 0.6r for a cylindrical ionization chamber in photon beams. However, prior studies have reported that this shift was excessively large. The objective of this study was to experimentally evaluate the EPOM shifts in photon beams for cylindrical ionization chambers, which are widely used in clinical practice, and thus determine the appropriate EPOM shift. A microdiamond detector, which is a semiconductor detector with a small sensitive volume, was used as a reference detector, and the EPOM shifts of 11 types of cylindrical ionization chambers were evaluated at 6 MV and 10 MV. The depth shift from the percent depth dose (PDD) of the reference detector to that of the evaluated chamber was calculated using the least-squares method and was defined as the EPOM shift. The EPOM shift of the 10 MV condition was slightly larger than that of the 6 MV condition. However, because this trend was not observed for all chambers, the results of the two energies were averaged, and the EPOM shifts were determined to be 0.33r-0.43r (± 0.05) for 10 types of ionization chambers, and 0.03r (± 0.03) for the A1SL chamber. The shifts for all ionization chambers were smaller than 0.6r, indicating that the recommended EPOM shifts were overestimated and the absorbed dose was underestimated at the calibration depth. Hence, the appropriate EPOM shift of the 10 types of ionization chambers was 0.4r (the geometric center of the A1SL chamber), with a dose uncertainty of 0.05%.

A new calibration method (roundabout method) was developed to precisely determine the amplification gains of 1013 Ω Faraday detectors.

We report a rare case of postoperative ascending colon cancer metastasis to the right external iliac lymph nodes. A 57- year-old woman underwent a laparoscopic right colectomy and D3 lymph node dissection. Pathological findings indicated a Stage Ⅲb, pT4aN1bM0 cancer. Because side effects were observed on adjuvant chemotherapy with FOLFOX, she was switched to S-1 administration every other week. Sixteen months postoperatively, right inguinal pain and elevated CEA values were noted. CT revealed two swollen right external iliac nodes with high FDG uptake on PET-CT. With the diagnosis of lymph node metastasis, an open celiotomy was performed to remove the lymph nodes. Pathological findings confirmed lymph node recurrence of ascending colon cancer. Postoperatively, her CEA values were normal and no recurrence was noted. This rare occurrence highlights the importance of examining adjacent lymph nodes for possible tumor recurrence. We report this case with the necessary literature review.

We report the gold-catalyzed reaction of vinyldiazo compounds and alkenylsilanes to produce skipped dienes, which are common structural motifs in an array of bioactive compounds. This carbon-carbon bond-forming transformation proceeds with complete regio- and stereoselectivity with the silyl group serving as a regio- and stereocontrolling element. Likewise, the use of alkynylsilanes as reaction partners yielded skipped enynes resulting from a C(sp)-C(sp3) coupling. Mechanistic experiments and DFT studies have provided support for a stepwise mechanism.

We prove a general stability theorem for $p$-class groups of number fields along relative cyclic extensions of degree $p^2$, which is a generalization of a finite-extension version of Fukuda's theorem by Li, Ouyang, Xu and Zhang. As an application, we give an example of pseudo-null Iwasawa module over a certain $2$-adic Lie extension., 7 pages. Archiv der Mathematik (2021)

Isotopic ratio measurements for 235U/238U and 234U/238U ratios were made for a series of solid materials using laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS). To extend the dynamic range of the isotopic ratio measurements, three Faraday detectors with different amplification gains (amplifiers with 1011 and 1013 ohm resistors) were employed. To reduce the sampling volume, isotopic ratio measurements were made on transient signals obtained by short-time LA duration (

A post-critically finite rational map ϕ of prime degree p and a base point β yield a tower of finitely ramified iterated extensions of number fields, and sometimes provide an arboreal Galois representation with a p-adic Lie image. In this paper, we take ϕ to be the monic Chebyshev polynomial x 2 − 2 , and we examine the size of the 2-part of the ideal class group of extensions in the resulting tower. In some cases, we prove an analogue of Greenberg's conjecture from Iwasawa theory. A key tool is a general theorem on p-indivisibility of class numbers of relative cyclic extensions of degree p 2 .

Background The purpose of this study was to evaluate the factors associated with asymptomatic splenic artery aneurysm (SAA) dilatation. Methods Among patients with SAA admitted to our department from 2001 to 2018, 70 lesions in 59 patients were selected and analyzed retrospectively. There were no cases of rupture or pregnancy in the follow-up period. We defined egg-shell appearance as SAA with >75% calcification of the outer shell. We measured the dilatation rate (mm/year) and evaluated the comorbidity and anatomical factors using univariate and multiple linear regression models. Post-hoc multiple linear regression models were fitted to evaluate the possible interactions. Results The mean age was 61.4 years (range 35–85 years), and the initial aneurysm diameter was 15.1 mm (range 3–47 mm). The mean dilatation rate was 0.26 mm/year (range 0–3.2 mm/year) during the follow-up period (average 4.6 years). Univariate analysis revealed that, portal hypertension (PHT) (P = 0.0003), egg-shell appearance (P = 0.007), and aneurysm diameter > 20 mm (P = 0.05) were significantly associated with the dilatation rate. Multivariate analysis revealed that egg-shell appearance was found to be an independent inverse risk factor of dilatation rate (P = 0.006). The multivariate analysis, including interaction terms, revealed a stronger effect of PHT and diameter >20 mm in cases with no egg-shell appearance (P = 0.08 and P = 0.05 for interactions, respectively). Conclusions The egg-shell appearance of SAA was an independent inverse risk factor affecting the SAA dilatation rate. The dilatation rates in the case of PHT and diameter >20 mm were restricted in the presence of the egg-shell appearance.

An 80-year-old female of Jehovah's Witness with anemia was diagnosed with advanced gastric cancer(cT4aN2M0, stage ⅢA). The first value of Hb at the clinic was 7.5 g/dL that made it difficult to perform total gastrectomy in safe. The treatment of blood augmentation included the administration of intravenous iron and oral intake of vitamins in the earlier period. The number of hemoglobin was not optimized sufficiently in the first 10 days, that necessitated administration of erythropoietin( ESPO® INJECTION: 24,000 unit×2 times). Hb value increased in 11.6 g/dL 34 days after the treatment, that enabled laparoscopic total gastrectomy to be performed. The tumor infiltrated left crus of diaphragm. The patient was discharged in 16th postoperative day with Hb value of 10.1 g/dL without any complications. Pathological findings showed pT4b(crus) N2M0, stage ⅢB. Preoperative blood augmentation benefited the patients with anemia who decline allogenic blood transfusion. Anemia with malignant tumors is associated with not only iron deficiency due to the chronic bleeding but also functional deficiency or iron sequestration due to malignant itself, inflammation and infection. Erythropoiesis along with infusion of iron contributed to the optimization of Hb value that ensure performing total gastrectomy in safe.

Phlegmasia cerulea dolens (PCD) is caused by obstruction of limb venous return that may result in venous gangrene and limb loss. We present a case of a fistula between a ruptured right common iliac artery aneurysm and the left common iliac vein (ilioiliac arteriovenous fistula [AVF]), which initially manifested as left PCD and acute renal failure. Resection of the aneurysm and repair of the AVF immediately improved the PCD and acute renal failure. We should be aware that an iliac AVF might present as PCD and should keep this in mind. Keywords: Phlegmasia cerulea dolens, Arteriovenous fistula, Acute renal failure

BACKGROUND Specialized proresolving mediators from ω-3 polyunsaturated fatty acid may control resolution of inflammation. We evaluated the influence of two specialized proresolving mediators, resolvin D1 (RvD1) and protectin D1 isomer (PD1 iso) on neointimal hyperplasia after balloon injury. MATERIALS AND METHODS Sprague Dawley male rats at 12-14 wk of age were injured as a model of balloon angioplasty. Then, 1 μg/rat of RvD1 or PD1 iso was administered intravenously via the tail vein immediately and 2 d after angioplasty. The proliferation of injured artery and the infiltration of leukocytes, monocytes, and macrophages at 3 d after injury were evaluated by immunostaining. The activity of the inflammatory transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) in the injured artery at 3 d after injury was evaluated using an enzyme-linked immuno sorbent assay kit. The proliferation of the neointima was evaluated by calculating the ratio of the neointimal and medial areas using specimens at 14 d after injury. RESULTS RvD1 and PD1 iso attenuated proliferation of medial cells (P

We construct a special $2$-adic Lie extension of a number field as an iterated tower by a conjugate of Joukowski map. If the number field is totally real, the unramified Iwasawa module over such a $2$-adic Lie iterated extension is conjecturally pseudo-null under Greenberg's conjecture for all intermediate cyclotomic $\mathbb{Z}_2$-extensions. We give some examples of such $2$-adic Lie iterated extensions with pseudo-null Iwasawa modules.

The Meyer-Schuster rearrangement of propargylic alcohols into α,β-unsaturated carbonyl compounds has been revisited by setting up an atom-economic process catalyzed by a deep eutectic solvent FeCl3·6H2O/glycerol. Isomerizations take place smoothly, at room temperature, under air and with short reaction times. The unique solubilizing properties of the eutectic mixture enabled the use of a substrate concentration up to 1.0 M with the medium being recycled up to ten runs without any loss of catalytic activity.

Background Systemic scleroderma (SSc) involves multiple organs including the skin, the lung, the kidney, and the esophagus. Nowadays, patient life prognosis has substantially improved due to more appropriate management of lung complications, including lung transplantation. However, the extension of their survival may increase SSc patients with chronic kidney diseases and requiring renal replacement therapy (RRT). Case presentation A 51-year-old female with SSc who underwent unilateral deceased-donor lung transplantation was referred because of progressive renal dysfunction. Despite no episodes of scleroderma renal crisis, her renal function gradually deteriorated for 2 years with her serum creatinine level increasing from 0.5 mg/dL at transplantation to 4.3 mg/dL. Although we reinforced antihypertensive treatment and reduced calcineurin inhibitor dose, she thereafter developed symptomatic uremia. Due to impaired manual dexterity with contracture of the interphalangeal joints, no caregivers at home, and kidney transplantation donor unavailability, maintenance hemodialysis was chosen as RRT modality. Further, due to the narrowing of superficial vessels in the sclerotic forearm skin and post-transplant immunocompromised status, the native left brachiocephalic arteriovenous fistula was created. Post-operative course was uneventful while any sign of cutaneous infection and pulmonary hypertension was closely monitored. Our literature review also indicates several difficulties with initiating and maintaining RRT in patients with SSc although case reports of kidney failure after lung transplanation in SSc were not accumulated. Conclusions With respect to initiating RRT for post-lung transplant patients with SSc, the clinical course of our case exemplifies recent complex trends of renal management. The optimal modality with secured initiation of RRT should be carefully determined based on the severity and risk for the cardiopulmonary, peripheral vascular, cutaneous, and systemic or local infectious complications.

An iterated tower of number fields is constructed by adding preimages of a base point by iterations of a rational map. A certain basic quadratic rational map defined over the Gaussian number field yields such a tower of which any two steps are relative bicyclic biquadratic extensions. Regarding such towers as analogues of $\mathbf{Z}_{2}$-extensions, we examine the parity of 2-ideal class numbers along the towers with some examples.

Objective: To create a web application that can evaluate suture performance and assess its quality. Material and Methods: We developed the web application using a few cloud computing systems, servers, database, and computing languages. We used 20 anastomosed graft samples for optimizing the application. The images of the anastomosed grafts were captured two-dimensionally. Five vascular surgeons utilized the application to compute the objective score and rank the score of the anastomoses subjectively. Results: Steps for using the application include uploading a two-dimensional image of sutures, tracing the stitch line manually, and pushing the button to have the score displayed. After using this system for more than 1,000 times without server issues or failures, we confirmed its stability and easy accessibility. The system calculated the score within several seconds. The score of the three factors (bite, pitch, and skewness of angle) ranged from 0.25 to 0.76. The error range of the application was acceptable. The interclass correlation coefficient (ICC (2,1)) of the three factors was 0.92. Conclusion: The quality of the application was acceptable considering the low range of interoperator variations in the scores.

In this study, we demonstrate the EEG activation patterns during the performance of different difficulty and duration of mental tasks in normal subjects. The EEG was recorded when the subjects performing mental tasks, and the power spectrum was calculated in alpha (8~13Hz) and beta (14~40Hz) frequency band. Maze tasks with different difficulty (size) and duration (execution time) were utilized to control the variability of mental workload. Statistical analysis showed that the decrease in alpha-band activity and the increase in betaband activity were marked between resting condition and performing mental tasks. Here no significant difference was found in the EEG activate pattern between task difficulty and task duration. In conclusion, these results imply that the fact of performing mental tasks is the main player in changing the activation pattern of alpha- and beta-band activity under the combined mental stress.

In most human movement tasks, the same goal can be achieved by a diversity of coordination patterns. For instance, when learning to juggle, individuals adopt their own unique coordination patterns in the early stages of acquiring the fundamental skills of juggling. These individual differences in the learning paths lead to differences in adaptability to new constraints. However, the reason for these differences in adaptability is still unknown. To address this problem, we quantified these differences in terms of attractor stability of the coordination patterns of expert jugglers using Recurrence Quantification Analysis. Furthermore, we quantified the attractor stability of intermediate jugglers and examined adaptability in a sensorimotor synchronization task. We found differences in attractor stability among coordination patterns of expert jugglers, as well as a difference in attractor stability between intrinsic coordination patterns of intermediate jugglers. Whereas, almost no significant direct correlation between attractor stability and adaptability of intermediate jugglers was found, suggesting a difference in both attractor stability and adaptability between intrinsic coordination patterns such that the difference in attractor stability might affect adaptability to new constraints. We submit that the learning path selected by each learner in the early stages of learning plays an important role in the subsequent development of expertise.

People suffering from dementia often forget to drink water due to deterioration of their cognitive functions. Usually water intake of these people is managed by care workers. However, the water intake cannot be monitored while the care workers are absent. Therefore, if we could estimate water intake of the patients while the care workers are absent, we could better manage the water intake of said patients. Therefore, in this paper, we propose a method for estimating water intake by measuring vibrations caused by larynx movement and swallowing sounds.When we ingest water, the larynx rises up with a vibration of 1 Hz to 20 Hz in the pharyngeal stage, and water flows into the stomach with a swallowing sound of frequency 400 Hz to 750 Hz in esophageal stage. Here, we assume that water intake is associated with the vibration and the swallowing sound. To measure the vibration and the swallowing sound, we developed two sensing devices based on an electret condenser microphone. The first device is an earphone-type device that measures the swallowing sound. The other sensing device is a neck-collar type device and measures the vibrations caused due to larynx movement. Output signals from the earphone-type device and the neck-collar type device are filtered by band-pass filters with passbands of 1 Hz to 20 Hz, and 400 Hz to 750 Hz, respectively. To estimate the water intake, we apply the dynamic time warping (DTW) algorithm that can take time dynamics into account for template matching method. The template data, which have n types of labels representing the water intake, is prepared in advance. Water intake is estimated by comparing the unknown data with the template data and selecting the label which gives minimum DTW distance.We conducted an experiment with two healthy subjects in their twenties. Each subject wears the proposed sensing devices. The sampling frequency is 25 kHz and measurement time is 3.2 s. In this experiment, n is set to three different values: 5 ml, 10 ml, and 15 ml. These are used as labels for the template data. Three trials were conducted for each round of water intake; therefore, the total number of observations is 18. The leave-one-data-out cross validation is applied, and accuracy is calculated to be 0.78. This result indicates that the proposed method can be helpful for the improvement of food management.

Gold-catalysis has enabled new synthetic opportunities in the chemistry of vinyldiazo compounds. Herein, we report the gold-catalyzed reaction of stabilized vinyldiazo compounds with pinacol alkenylboronates to provide boryl-functionalized cyclopentene derivatives through a formal [3+2] carbocycloaddition reaction, a very unusual pathway in alkenylboronate chemistry. This reaction proceeds with high regio- and stereoselectivity. The synthetic usefulness of the resulting borylated cyclopentene derivatives toward the synthesis of densely functionalized cyclopentanoids is also demonstrated.

The prevalence of arteriosclerosis obliterans (ASO) and critical limb ischemia (CLI) is currently increasing, and arterial reconstruction is often attempted to salvage the limb. Some patients cannot undergo attempted revascularization because of contraindications, and they only receive conservative treatment. In this study, we investigate the comorbidities and survival rates of patients with CLI who receive conservative treatment. Thirty-five patients with CLI due to ASO, who had not undergone revascularization surgery (C group), were enrolled. As controls, 136 patients with CLI due to ASO who did undergo revascularization (R group), mainly via bypass surgery, were enrolled. Coronary artery disease, heart failure, and respiratory dysfunction were factors indicating conservative treatment. Limb salvage rates and survival rates were not significantly different between the two groups. Patients who had survived for less than two years after surgery had a higher prevalence of chronic heart failure, cardiovascular disease, and end-stage renal disease compared to patients who had survived for more than two years. The use of statins, dual antiplatelets, aspirin, or warfarin did not influence whether a patient survived for longer than two years. 77% of patients survived for more than two years after receiving only conservative therapies. Surgical revascularization did not improve the prognosis of patients with CLI as compared with the conservative therapy. Clinicians might start with conservative treatment while considering other treatment options for patients with CLI.

The main objective is to examine whether the severity of peripheral arterial disease (PAD) affects the expenses and hospital stay of the patients who undergo bypass surgery below the inguinal ligament for PAD. Eighty consecutive patients who underwent infrainguinal bypass surgery for PAD between January 2012 and December 2014 were included in the study. Patients were divided into groups according to their critical limb ischemia (CLI) symptoms and the Wound, Ischemia, and Foot Infection (WIfI) classification. As endpoints, we assessed the duration of postoperative hospital stay and expenses during hospitalization. CLI was a significant factor for longer hospital stay and increased medical expenses (p = 0.009 and p = 0.001). In the patients with CLI, significant factors for longer hospital stay and increased medical expenses were (1) history of distal bypass (p = 0.33 and p = 0.003, respectively) and stage 4 local lower limb status in WIfI classification (p = 0.0007 and p = 0.053). PAD severity was associated with prolonged postoperative hospital stay and increased medical expenses. The presence or absence of CLI and its severity according to the WIfI classification correlated with medical expenses and hospital stay duration between the milder and severe groups.

Objective: To elucidate the outcomes of open surgery for popliteal artery aneurysm (PAA) in a single Japanese institution. Materials and Methods: Between 1999 and 2016, 35 patients (44 PAAs) underwent open surgery in our department. The first-line surgical strategy involved the medial approach, with excision of the aneurysm sac and autologous vein bypass grafting. Associations between the outcomes and 1) the surgical management of the aneurysmal sac (aneurysmectomy vs. ligation with bypass) and 2) the preoperative clinical symptoms were evaluated. Results: There were no aneurysm-related deaths during the follow-up period (mean, 4 years; range, 1 - 17.6 years). The 5-year primary, primary-assisted, and secondary patency rates were 67.9%, 72.7%, and 94.5%, respectively. Re-intervention was required for 19 PAAs (14 patients), including two PAAs in patients with suspected Behcet’s disease. Patency rates did not differ between the aneurysmectomy and ligation groups. Remnant sac enlargement occurred in 3 cases. Among asymptomatic patients, clinical symptoms did not deteriorate; however, the ankle brachial pressure index decreased ≥0.15 in patients with artery-graft mismatching. Conclusion: Patency rates were good, and our modified ligation with bypass procedure, which involves excising the sac as much as possible, exhibited less risk in terms of remnant sac enlargement compared to that in previous studies.

A malignant tumor can cause hypercoagulation and it also often coexists with thrombosis. Cisplatin-based chemotherapy can also induce adverse vascular effects, including arterial thrombosis. We herein report a case of acute arterial thrombosis in a patient undergoing postoperative adjuvant cisplatin-based chemotherapy for completely resected lung cancer. The patient complained of acute leg pain after chemotherapy, and computed tomography revealed multiple thrombi from the thoracic to popliteal arteries. Arterial thrombosis during adjuvant chemotherapy is extremely rare; however, careful clinical observation of patients receiving cisplatin-based chemotherapy is important, because arterial thrombosis, even in the absence of the primary malignant tumor, is possible.

Low rates of arteriovenous fistula (AVF) maturation prevent optimal fistula use for hemodialysis; however, the mechanism of venous remodeling in the fistula environment is not well understood. We hypothesized that the embryonic venous determinant Eph-B4 mediates AVF maturation. In human AVF and a mouse aortocaval fistula model, Eph-B4 protein expression increased in the fistula vein; expression of the arterial determinant Ephrin-B2 also increased. Stimulation of Eph-B-mediated signaling with Ephrin-B2/Fc showed improved fistula patency with less wall thickness. Mutagenesis studies showed that tyrosine-774 is critical for Eph-B4 signaling and administration of inactive Eph-B4-Y774F increased fistula wall thickness. Akt1 expression also increased in AVF; Akt1 knockout mice showed reduced fistula diameter and wall thickness. In Akt1 knockout mice, stimulation of Eph-B signaling with Ephrin-B2/Fc showed no effect on remodeling. These results show that AVF maturation is associated with acquisition of dual arteriovenous identity; increased Eph-B activity improves AVF patency. Inhibition of Akt1 function abolishes Eph-B-mediated venous remodeling suggesting that Eph-B4 regulates AVF venous adaptation through an Akt1-mediated mechanism.

This paper presents a novel atomic force microscopy (AFM)-based nanofabrication technique for Si in water that is based on highly localized catalytic etching with a Pt-coated AFM probe. It has been shown that nanoscale grooves can be fabricated on the Si surface at room temperature via Pt-assisted catalytic chemical etching in water without the addition of any chemicals. Furthermore, dissolved oxygen (O2) in water has been found to be a key element for driving the chemical reaction of Si with water in the Si removal process. Experimental results have also suggested that an oscillating cantilever of the Pt-coated AFM probe for the stirring of water is essential in order to overcome the oxygen mass-transfer limitations and enhance the Si removal rate. The elementary chemical reactions taking place during the etching of Si has been estimated on the basis of electrochemical theory. It is proposed that in the first step, dissolved oxygen is reduced and forms hydroxide ions (OH−) with water molecules (H2O) on the surface of the Pt-coated tip. In the second step, Si atoms are oxidized on reaction with OH− ions and water soluble silicates are formed. The catalytic reaction taking place on the surface of a Pt-coated tip can be enhanced by the application of an anodic potential to an additional Pt wire electrode, resulting in a dramatic fifty-fold increase in the Si removal rate.

Autogenous vein grafts remain the gold standard conduit for arterial bypass, particularly for the treatment of critical limb ischemia. Vein graft adaptation to the arterial environment, i.e., adequate dilation and wall thickening, contributes to the superior performance of vein grafts. However, abnormal venous wall remodeling with excessive neointimal hyperplasia commonly causes vein graft failure. Since the PREVENT trials failed to improve vein graft outcomes, new strategies focus on the adaptive response of the venous endothelial cells to the post-surgical arterial environment. Eph-B4, the determinant of venous endothelium during embryonic development, remains expressed and functional in adult venous tissue. After surgery, vein grafts lose their venous identity, with loss of Eph-B4 expression; however, arterial identity is not gained, consistent with loss of all vessel identity. In mouse vein grafts, stimulation of venous Eph-B4 signaling promotes retention of venous identity in endothelial cells and is associated with vein graft walls that are not thickened. Eph-B4 regulates downstream signaling pathways of relevance to vascular biology, including caveolin-1, Akt, and endothelial nitric oxide synthase (eNOS). Regulation of the Eph-B4 signaling pathway may be a novel therapeutic target to prevent vein graft failure.