Seal Mechanism of Tip Seal in Scroll Compressor

Scroll compressors are widely used in room air conditioning cycles, package air conditioning cycles, refrigeration, water heater and automobile air conditioning cycles as well as air compressors, helium compressors and vacuum pump. There are two main leakage paths in a compression chamber formed by a fixed scroll and an orbiting scroll. One is the leakage path through a radial clearance between the wraps of fixed and orbiting scroll. The leakage through the radial clearance is prevented by pressing the orbiting scroll radially against the fixed scroll by a mechanism such as a compliance mechanism. Oil inside the compression chamber also has the sealing effect and reduces the leakage through the radial clearance. Another leakage path is an axial clearance which is the clearance between a tip of the scroll wrap and a base plate. A tip seal is often used to prevent the leakage through the axial clearance. Although there have been many studies on the tip seal, the seal mechanism of the tip seal is not thoroughly clarified yet, and the influence of design parameters on efficiency of the tip seal is unclear. In addition, the relationship between the sealing effect and a frictional loss of the tip seal is also not validated well. In this study, a test apparatus which can evaluate the sealing effect and the frictional loss of the tip seal simultaneously is developed. The influence of several design parameters on the sealing effect and the frictional loss is examined with the test apparatus. By measuring pressure distribution around the tip seal in a tip seal groove, the sealing mechanism of the tip seal is clarified and a design guideline of the tip seal groove is obtained

Giant superconducting diode effect in ion-beam patterned Sn-based superconductor nanowire / topological Dirac semimetal planar heterostructures

Superconductor/topological material heterostructures are intensively studied as a platform for topological superconductivity and Majorana physics. However, the high cost of nanofabrication and the difficulty of preparing high-quality interfaces between the two dissimilar materials are common obstacles that hinder the observation of intrinsic physics and the realisation of scalable topological devices and circuits. Here, we demonstrate an innovative method to directly draw nanoscale superconducting beta-tin (beta-Sn) patterns of any shape in the plane of a topological Dirac semimetal (TDS) alpha-tin (alpha-Sn) thin film by irradiating a focused ion beam (FIB). We utilise the property that alpha-Sn undergoes a phase transition to superconducting beta-Sn upon heating by FIB. In beta-Sn nanowires embedded in a TDS alpha-Sn thin film, we observe giant non-reciprocal superconducting transport, where the critical current changes by 69% upon reversing the current direction. The superconducting diode rectification ratio reaches a maximum when the magnetic field is applied parallel to the current, distinguishing itself from all the previous reports. Moreover, it oscillates between alternate signs with increasing magnetic field strength. The angular dependence of the rectification ratio on the magnetic field and current directions is similar to that of the chiral anomaly effect in TDS alpha-Sn, suggesting that the non-reciprocal superconducting transport may occur at the beta-Sn/alpha-Sn interfaces. The ion-beam patterned Sn-based superconductor/TDS planar structures thus show promise as a universal platform for investigating novel quantum physics and devices based on topological superconducting circuits of any shape.Comment: 22 pages, 6 figure

Proton Decay in the Semi-Simple Unification

Semi-simple unification is one of a model which naturally solves two difficulties in the supersymmetric grand unification theory: doublet-triplet splitting problem and suppression of dimension 5 proton decay. We analyzed the dimension 6 proton decay of this model using perturbative analysis at the next-to-leading order. The life time of proton is 3 \times 10^{34} - 10^{35} years for wide range of SUSY breaking parameters, and there is an intriguing possibility of observing proton decay signals in the next-generation water Cherenkov detectors such as Hyper-Kamiokande and TITAND. Several uncertainties in this prediction are also discussed.Comment: 16 pages, including 2 tables and 3 figures, UT-97

Effect of AZD1480 in an epidermal growth factor receptor-driven lung cancer model

Objective: STAT3 plays a vital role in inducing and maintaining a pro-carcinogenic inflammatory microenvironment and is reported to be a critical mediator of the oncogenic effects of EGFR mutations. STAT3 activation is mediated through JAK family kinases. We investigated the effect of the JAK1/2 inhibitor AZD1480 on lung tumors induced by an activating EGFR mutation. Materials and methods: Three EGFR tyrosine kinase inhibitor-resistant cell lines (RPC-9, PC-9/Van-R and PC-9/ER3) established from PC-9 harboring an EGFR exon19 deletion mutation were used. Growth inhibition was measured using an MIT assay. Effects of AZD1480 were also evaluated in the xenograft model and in the EGFR transgenic mice model. Protein expressions were assessed by immunoblotting and immunohistochemistry. Group differences were compared using Student's t-test. To evaluate the efficacy of AZD1480 on survival, AZD1480 or vehicle was administered orally from 7 weeks of age of the transgenic mice. Overall survival curves were calculated using the Kaplan-Meier method. Results: The sensitivities of resistant and parent cells to AZD1480 were similar in vitro. AZD1480 (30 or 50 mg/kg/day, per os) reduced angiogenesis and revealed significant tumor regression in a mouse xenograft model: Subsequently, the transgenic mice were treated with AZD1480 (30 mg/kg/day) or vehicle alone. The numbers of lung tumors (long axis exceeding 1 mm) in the AZD1480-treated group and control group were 0.37 +/- 0.18 and 2.25 +/- 0.53 (p <0.001), respectively. AZD1480 treatment suppressed pSTAT3, pJAK1, pJAK2 and angiogenesis. The median survival time in the AZD1480-treated group (217 days) was significantly greater than that in the control group (106 days) (log-rank test, p <0.0001). Conclusion: AZD1480 may be effective against lung tumors driven by an activating EGER mutation

Impact of CRAB symptoms in survival of patients with symptomatic myeloma in novel agent era

The acronym CRAB summarizes the most typical clinical manifestations of multiple myeloma, these being hypercalcemia, renal failure, anemia, and bone disease. CRAB can be used to distinguish between active, symptomatic multiple myeloma and monoclonal gammopathy of undermined significance or smoldering myeloma. The distinction is relevant not only for classification and diagnosis but also for therapy. CRAB factors influence the prognosis of multiple myeloma. However, it is unclear whether the presence of CRAB factors has an influence on the prognosis of myeloma treated with novel agents. In the current study, patients with hypercalcemia and bone disease showed a significantly worse prognosis, whereas anemia and renal failure showed no difference in survival. Novel agents used for treatment of patients with renal failure suggested a favorable outcome compared with conventional therapy. Bone disease was the most common factor and may have the strongest prognostic value in symptomatic myeloma patients using novel agents

Clinical significance of dasatinib-induced pleural effusion in patients with de novo chronic myeloid leukemia

Dasatinib is currently approved for clinical use as a first-line treatment agent for newly diagnosed chronic myeloid leukemia (CML). However, only a few clinical trials have been performed to evaluate dasatinibinduced PE following first-line therapy. We investigated the incidence and clinical features of dasatinib-induced PE following first-line therapy in Japanese CML patients of real world clinical practice settings. Among 22 patients, the median age of PEpositive patients was higher than that of PEnegative patients. Major molecular response was achieved in 75% of PE-positive patients and 50% of PE-negative patients. Most patients developed PE more than 1 year after treatment. Appearance of PE is associated with better clinical response during dasatinib treatment, however it is developed at any time. Elderly and high-risk patients tend to develop PE. The clinical features of dasatinib-induced PE following first-line therapy might be late onset and might not immediately follow the increasing of large granular lymphocyte

Novel prospective umbrella-type lung cancer registry study for clarifying clinical practice patterns: CS-Lung-003 study protocol

Introduction Conventional cancer registries are suitable for simple surveillance of cancer patients, including disease frequency and distribution, demographics, and prognosis; however, the collected data are inadequate to clarify comprehensively diverse clinical questions in daily practice. Methods We constructed an umbrella‐type lung cancer patient registry (CS‐Lung‐003) integrating multiple related prospective observational studies (linked studies) that reflect clinical questions about lung cancer treatment. The primary endpoint of this registry is to clarify daily clinical practice patterns in lung cancer treatment; a key inclusion criterion is pathologically diagnosed lung cancer. Under this registry, indispensable clinical items are detected in advance across all active linked studies and gathered prospectively and systematically to avoid excessive or insufficient data collection. Researchers are to input information mutually, irrespective of the relevance to each researcher's own study. Linked studies under the umbrella of the CS‐Lung‐003 registry will be updated annually with newly raised clinical questions; some linked studies will be newly created, while others will be deleted after the completion of the analysis. Enrollment began in July 2017. Discussion We successfully launched the umbrella‐type CS‐Lung‐003 registry. Under this single registry, researchers collaborate on patient registration and data provision for their own and other studies. Thus, the registry will produce results for multiple domains of study, providing answers to questions about lung cancer treatment raised by other researchers. Through such analysis of each linked study, this registry will contribute to the comprehensive elucidation of actual daily practice patterns in lung cancer treatment. Key points CS‐Lung‐003 registry directly integrates multiple linked studies created under the umbrella of this cancer registry to solve various clinical questions regarding daily practice patterns of lung cancer treatment