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The present work experimentally and numerically investigates the local heat transfer enhancement induced by a piezoelectric fan interacting with a cross flow in a local heated channel. The piezoelectric fan is placed along the flow direction and tested under different amplitudes and flow rates. In the simulations, a spring-based smoothing method and a local remeshing technique are used to handle the moving boundary problems. Hybrid mesh is used to reduce the size of dynamic mesh domain and to improve computational efficiency. The experimental and numerical values of the time-averaged mean Nusselt number are found to be in good agreement, with deviations of less than 10%. The experimental result shows that the heat transfer performance of the heated surfaces is substantially enhanced with a vibrating piezoelectric fan. The numerical result shows that the heat transfer enhancement comes from the strong longitudinal vortex pairs generated by the piezoelectric fan, which significantly promote heat exchange between the main flow and the near-wall flow. In the case of a=0.66 (a is the dimensionless amplitude) and Re=1820, the enhancement ratio of the time-averaged mean Nusselt number reaches 119.9%.

Research on the dynamic properties of a plasma sheath coupled with pitching motion of the vehicle has great significance in solving the problem of communication interruption in the process of vehicle reentry. This paper investigates the dynamic properties of the plasma sheath by using the simplified conventional Burnett (SCB) equations and the Navier-Stokes (NS) equations with the thermochemical non-equilibrium effect. The eleven-species chemical kinetic models are applied to the comparison and there is verification of a dynamic plasma sheath simulation for the first time. After the introduction of vehicle pitching motion, the dynamic results are more consistent with the experimental data than the simulated results when treating it as static state. The plasma sheath characteristic parameters show periodic properties, whose changing period is the same as the pitching motion period. However, because of different velocities of the pitching motion, phase shifts exist in different positions of the vehicle. The enhancement of the rarefied effect weakens the disturbance to the plasma sheath. This research reveals the distribution and regularities of the dynamic plasma sheath. It is significant in solving the ionization blackout problem and the design of the reentry vehicle, and provides reliable data for further research on the dynamic plasma sheath.

Early detection of lung cancer has a higher likelihood of curative treatment and thus improves survival rate. Low-dose computed tomography (LDCT) screening has been shown to be effective for high-risk individuals in several clinical trials, but has high false positive rates. To evaluate the risk of stage I lung cancer in the general population not limited to smokers, a retrospective study of 133 subjects was conducted in a medical center in Taiwan. Regularized regression was used to build the risk prediction model by using LDCT and health examinations. The proposed model selected seven variables related to nodule morphology, counts and location, and ten variables related to blood tests and medical history, achieving an area under the curve (AUC) value of 0.93. The higher the age, white blood cell count (WBC), blood urea nitrogen (BUN), diabetes, gout, chronic obstructive pulmonary disease (COPD), other cancers, and the presence of spiculation, ground-glass opacity (GGO), and part solid nodules, the higher the risk of lung cancer. Subjects with calcification, solid nodules, nodules in the middle lobes, more nodules, and diseases related to thyroid, liver, and digestive systems were at a lower risk. The selected variables did not indicate causation.

Background Mounting evidence has shown that circular RNAs (circRNAs) have vital roles in human cancers, including retinoblastoma (RB). The purpose of this study was to investigate the exact roles and underlying mechanism of circRNA ER membrane protein complex subunit 9 (circ-FAM158A) in RB. Methods Quantitative real-time polymerase chain reaction (qRT-PCR) was carried out to determine the expression levels of circ-FAM158A, miR-138–5p and solute carrier family 7 member 5 (SLC7A5). Cell proliferation was evaluated by Cell counting Kit-8 (CCK-8) assay and colony formation assay. Flow cytometry analysis was applied to determine cell cycle distribution and apoptosis rate. Transwell assay was conducted to assess cell migration and invasion. The interaction between miR-138–5p and circ-FAM158A or SLC7A5 was predicted by starBase v2.0 and confirmed by dual-luciferase reporter assay. Western blot assay was performed to examine the protein expression of SLC7A5. The mice xenograft model was established, immunohistochemistry (IHC) and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling (TUNEL) assays were conducted to confirm the role of circ-FAM158A in vivo. Results Circ-FAM158A and SLC7A5 were overexpressed and miR-138–5p was downregulated in RB tissues and cells. Circ-FAM158A knockdown inhibited RB cell proliferation, metastasis, and promoted apoptosis in vitro and in vivo. MiR-138–5p was a direct target of circ-FAM158A, and miR-138–5p inhibition reversed the inhibitory effect of circ-FAM158A silence on the progression of RB cells. Additionally, SLC7A5 was identified as a target of miR-138–5p, and SLC7A5 overexpression abated the anti-tumor roles of miR-138–5p in RB cells. Besides, circ-FAM158A positively regulated SLC7A5 expression by sponging miR-138–5p. Conclusion Circ-FAM158A knockdown inhibited the progression of RB by regulating miR-138–5p/SLC7A5 axis, which provided new insights into the pathogenesis of RB.

Multilayer cutting is widely used in finish machining process of thin-walled parts to improve the machining precision. The paper presents a cutting allowance optimization method using genetic algorithm to improve the machining quality and efficiency of thin-walled parts in the field of aerospace. Considering the coupling relationship of the deformation between the layers in layered milling, the parameterized finite element model of thin-walled parts in side milling process is established. The best relationship between the workpiece stiffness and the cutting force is determined though iterative calculations, and the deformation caused by the cutting force can be minimized. The results show that the optimized distribution of the depth of finishing cutting was better than the experience. The method proposed in this paper can reduce the deformation of the workpiece during the machining process, and thus improve the machining accuracy.

The combination of a microchannel and a circular synthetic jet has been proven as a promising cooling technology for microelectronic devices. However, the flow control and heat transfer characteristics of a circular synthetic jet in a microchannel are still not clear. This work numerically investigates the interaction between a circular synthetic jet and a cross flow in a microchannel using an in-house solver based on the finite volume method and analyzes its impact on the heat transfer process to further understand the heat transfer enhancement induced by a circular synthetic jet in a microchannel. The effects of the synthetic jet Reynolds number (Resj = 0 to 324), dimensionless stroke length (L/H = 1.8432 to 92.16), and cross-flow Reynolds number (Rec = 188 to 470) are studied herein. The results show that the main body of the vortex structure generated by the circular impinging synthetic jet during the discharge stage is a hairpin vortex. During the downstream motion of the hairpin vortex, the vortex legs gradually stretch and evolve into a pair of large-scale longitudinal vortex. The heat transfer enhancement induced by a circular synthetic jet can be divided into two parts according to the difference in acting mechanism: an impinging region with severe heat transfer fluctuation and an entraining region with a relatively stable heat transfer performance. The parametric study demonstrates that the enhancements of the time-area-averaged Nusselt number and the total pressure drop are mainly affected by Resj, while the transient heat transfer performance is determined by L/H. Furthermore, the growth rates of the time-area-averaged Nusselt number and the total pressure drop are almost independent of Rec.

The thermal performances of high-speed angular contact ball bearings have not been thoroughly addressed so far. The effect of contact angle on the thermal expansion and deformation of bearings was not fully considered. Meanwhile the influence of substructures on heat exchange, especially the assembly constraints and cooling/lubrication systems significantly impacting bearing temperature were not well characterized. Again, the heat transfer of various bearing's sub sources based on different heat generation mechanisms was seldom discussed independently. In this paper, the influence of contact angle on thermal deformation was first factored into the force equilibrium of angular contact ball bearings to calculate the bearing loads and then heat generation, and the heat generation and transfer of each sub heat source were detailed. Next, the lubricant, radial/axial structural constraints and assembly relations between parts were fully analyzed in affecting bearing temperature. The heat exchange of cooling unit was modeled and the equivalent size of coolant passage was determined to facilitate the thermal estimation. On these bases, an integrated comprehensive thermal grid model for a pair of front bearings of high-speed spindle and their surroundings was developed to forecast the temperature rise of bearings. Finally, the bearing temperature variation, for the purpose of validation, was tested and compared with the corresponding numerical solutions. As a result, the bearing temperature can be better forecasted when using the developed model.

The ruled surface of impeller is widely used in the industry of automobile, shipbuilding, aerospace and aeronautics. Researches on the manufacture of blade possess general meaning. The importance of their performance in the certain field and the non-replace ability of their functions in the specified mechanical systems have resulted in that the technology of manufacturing and measurement for ruled surfaces has been a critical research project in the field of dimensional manufacturing and measurements. With the rapid development of the modern science and technology, complex ruled surfaces are employed more and more widely, but their tolerances become narrower and narrower. The common impeller surfaces represented by NURBS are given and then curve and surface interpolation algorithm represented by NURBS are presented. These provide theoretical foundation for NC machining programming of impeller surface. Principals of normal offset curve and inclined offset surface are used to simplify the model. The NC milling method of divide area is presented to raise machining efficiency and to improve quality of machined surface. The machining efficiency is important in line property of rule surface, flank milling rule surface with end-milling, improve surface quality and cutter efficiency. This paper presents a calculate method to generate five-axis flank milling NC code of divide area in the blade of compressor with Vericut simulating the five-axis flank milling NC code and measurement the result of processing that verification the precision of five-axis flank milling. This paper also simulates four-axis machining for comparing cutting efficiency between five-axis machining and four-axis machining and the status of both the great differences in processing efficiency.

Roundness and spindle error motion measurements are two fundamental issues in the geometrical measuring techniques. Most of the fixture with rotating cylindrical shaft, cylinder defined by the minimum circumscribed axis, can be obtained the minimum circumscribed rotation surface high-precision axis. Generally, a more accurate measurement points, can result in a more accurate cylindrical shaft, but the longer the time of the calculation time. In this paper, the drawing method can handle a large number of measurement data to avoid lengthy and complicated calculations, and can quickly obtain the minimum circumscribed cylindrical axis precise location, deviation and cylindrical radius and tolerance. This article is the use of the minimum circumscribed cylinder theoretical approach with computer drawing ways. Comparison is relatively quick and easy. The actual display of the results, which can be easily, obtained the position, skew and deviation of the spindle. This paper will be established a cylindrical outer edge quality assessment model and provided a basis for the cylindrical outer edge quality assessment. This paper for seeking the axis of cylindrical shank is based on minimum circumscribed cylindrical theory with computer drawing method and instances for verification. The computer drawing method can be determined spindle eccentric angle and the distance of deviation, to provide a reliable model for the evaluation of rotary spindle, the mode established by the paper at the same time applicable to any other rotating spindle error evaluation.

Machining accuracy of thin-walled parts is easily affected by clamping and cutting deformation due to its poor stiffness. In this paper, synchronous optimization method of clamping force and cutting parameters is presented based on GA and FEM. The optimization objective is to minimize the maximum deformation and to improve the machining efficiency. GA is used to optimize cutting parameters and clamping force, and FEM is used to predict the machining deformation of the thin-walled workpiece. Finally, taking a titanium alloy thin-walled part with irregular shape as an example, the optimal clamping force and cutting parameters at every cutting position are obtained to demonstrate the feasibility of the method.

Large gantry machining centers are used for machining of products in almost all industry. To raise the design and production efficiency of machining centers, an integrated method of fast design and analysis is proposed in this paper. Firstly, large components unit structures are decomposed and extracted based on functions and structures. Then, after conducting fast analysis using APDL programming, a method of Comprehensive Evaluation is employed to optimal select the design schemes. Finally, the column of large gantry machining center QLMT6300 is taken as example to illustrate the validity of the method presented.

The autoclave moulding process of composites is characterized by reentrance, capacity and time constraints. Its scheduling directly affects productivity and production cycle of composites. Scheduling methods in the existing literature can't meet the requirements of its scheduling optimization. Aiming at improving utilization and reducing energy consumption of autoclave, based on the Theory of Constraints, a heuristic algorithm considering the capacity and time constraints is proposed to solve the scheduling problem, and priority scheduling rules are established. The studying of a case shows the effectiveness of the algorithm.

Patients with high vancomycin minimum inhibitory concentrations (MICs) and heteroresistant vancomycin-intermediate Staphylococcus aureus (hVISA) infection are associated with treatment failure and poor outcomes. The main purpose of this study was to investigate the effect of hVISA on patient outcome, considering both the high vancomycin MIC and the existence of heteroresistant phenotypes. From January 2005 to December 2009, consecutive meticillin-resistant S. aureus (MRSA) isolates from 284 cases of MRSA bacteraemia receiving glycopeptide therapy were collected for further MIC and hVISA testing. The demographic distribution, clinical features and outcomes in bacteraemia patients with different vancomycin MICs and hVISA status in MRSA isolates were subsequently compared. Subjects were divided into three groups: low vancomycin MIC (

An approach to optimize the cutting parameters based on Particle Swarm Algorithm(PSO) and Finite Element Method(FEA) was proposed. A cutting parameters optimization model was established whose design variables are the cutting parameters and objective function is to minimize the maximum deformation. PSO was used to optimize the cutting parameters and FEA was utilized to predict the machining deformation of the thin-walled workpiece. Finally, the entire technique was demonstrated in a case study. The simulation and experimental results show that the approach can be further employed into the practical machining situation.

Hashimoto disease (HD) is an autoimmune thyroid disease resulting from complex interactions between genetic and environmental factors. The human leukocyte antigen (HLA) gene has been established to be involved in the susceptibility to HD. We aim to investigate the associations between HLA-B alleles and Han Chinese children with HD by both case-control and family-based studies. A total of 108 unrelated children with HD, 380 unrelated healthy controls, 58 trios of affected patients and their parents, and 75 trios of unaffected siblings and their parents were recruited. HLA-B genotyping was performed by polymerase chain reaction and detected with a sequence-specific oligonucleotide probes system. We found that B*46:01 allele (OR = 2.31, 95% CI 1.60-3.34, P(c) = 9.99 × 10(-5)) and carrier (OR = 3.28, 95% CI 2.10-5.11, P(c) = 1.35 × 10(-6)) were associated with HD risk. Transmission/disequilibrium test further confirmed an overtransmission of the B*46:01 (OR 2.55, 95% CI 1.36-6.10, P = 6.5 × 10(-3)). The findings were similar in females when stratified by gender. In conclusion, our results clearly identify that HLA-B*46:01 confers susceptibility to HD in Han Chinese children. Further studies with larger children cohort are required to confirm the role of B*46:01 in the development of HD.

Graves disease (GD) is an autoimmune thyroid disease with a female preponderance and a wide range of ages at onset, and human leukocyte antigen (HLA) gene plays a primary role in the susceptibility to GD. We aim to investigate the associations between HLA-DRB1 alleles and Taiwanese children with GD by both case-control and family-based studies. A total of 241 unrelated children with GD, 539 healthy controls, 115 trios of affected patients and their parents, and 121 trios of unaffected siblings and their parents were recruited. HLA-DRB1 genotyping was performed by polymerase chain reaction and sequence-based typing assays. We found that DRB1*09:01 (OR = 2.60, 95% CI 2.02–3.35, Pc = 6.55 × 10−13) was associated with GD risk, while DRB1*12:02 (OR = 0.32, 95% CI 0.20–0.53, Pc = 4.55 × 10−5) was protective against GD. Transmission/disequilibrium test further confirmed an overtransmission of the DRB1*09:01 (OR 3.37, 95% CI 2.13–6.22, Pc = 1.0 × 10−5) and an undertransmission of the DRB1*12:02 (OR 0.21, 95% CI 0.05–0.42, Pc = 1.7 × 10−3). The findings were similar in females when stratified by gender. In conclusion, our results clearly identify that HLA-DRB1*09:01 confers susceptibility to GD and DRB1*12:02 exerts protection against GD development in Taiwanese children.

Cervical cancer is caused primarily by infection with oncogenic types of human papillomavirus (HPV). However, HPV infection alone is not sufficient for the progression to cervical cancer. Host immunogenetic factors may involve in the development of this disease. Inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) is recently shown to act as a negative regulator of T-cell activation. We aim to study if polymorphisms in the ITPKC gene are associated with the risk of cervical cancer in Taiwanese women. ITPKC rs28493229 C/G, rs890934 G/T, rs2303723 C/T, and rs10420685 A/G polymorphisms were genotyped in a hospital-based study of 465 women with cervical squamous cell carcinoma (CSCC) and 800 age-matched healthy control women. The presence and genotypes of HPV in CSCC were determined. The frequency of G/G genotype and G allele of the ITPKC rs28493229 polymorphism was significantly higher in patients with CSCC compared with controls (OR = 1.81, 95 % CI 1.20–2.73, P = 0.005, P c = 0.02; OR = 1.70, 95 % CI 1.14–2.54, P = 0.008, P c = 0.03, respectively). No significant associations were found for other 3 polymorphisms. Haplotype analysis revealed the distribution of haplotype CGTA was significantly reduced in women with CSCC (OR = 0.59, 95 % CI 0.40–0.89, P = 0.01, P c = 0.04). In conclusion, we found the G/G genotype and G allele of the ITPKC rs28493229 polymorphism may contribute to the risk of CSCC in Taiwanese women. This finding provides new insights into the mechanisms of immune activation in cervical cancer.

Escherichia coli producing the highly virulent, multidrug-resistant, CTX-M-15 extended-spectrum β-lactamase (ESBL), sequence type 131 (ST131), has emerged on three continents since the late 2000s. We described the molecular epidemiology, clinical features, and outcome of ESBL-producing E. coli bacteremia in Taiwan from 2005 to 2010. This study aims to determine whether the risk factors, clinical features, and outcomes of the ST131 isolate differ from those of non-ST131 isolates. From 2005 to 2010, we collected 122 nonduplicated, consecutive, ESBL-producing E. coli isolates from bloodstream infections in a 1,200-bed hospital in Taiwan. Isolates were characterized using multilocus sequence typing. Demographic data, clinical features, and outcomes were collected from medical chart records. Thirty-six (29.5%) patients with bacteremia with ESBL-producing E. coli ST131 were identified. Patients with clone ST131 were more likely to have secondary bacteremia and noncatheterized urinary tract infections ( P < 0.05). Secondary bacteremia (odds ratio [OR], 5.05; 95% confidence interval [CI], 1.08 to 23.56) and urinary catheter nonuse (OR, 3.77; 95% CI, 1.17 to 12.18) were independent risk factors for the ST131 clone after adjustment. Mortality rates at day 28 were similar in ST131 and non-ST131 populations. Independent risk factors predicting mortality at day 28 included malignancy, shock, and hospital-acquired bacteremia. In ESBL-producing E. coli bloodstream infections, the ST131 clone was not associated with health-care-associated risk factors, such as urinary catheter use or antibiotic exposure. Although highly virulent and multidrug resistant, the ST131 clone was not associated with higher mortality than non-ST131 clones.

The crossbeam is an important part in the gantry machining center which greatly affects the machining accuracy. Four kinds of crossbeam structure for the large machining center were designed and their static and dynamic characteristics were analyzed. The optimal crossbeam structure was selected by the comprehensive performance evaluation method. Then the thicknesses of rib plates in the crossbeam were defined as the optimization parameters after conducting the sensitivity analysis. The first four natural frequencies were defined as the objective functions and the static performance and the mass were defined as the constraint conditions. The optimal sizes of the rib plates in the crossbeam were obtained by the optimization analysis. Finally the feasibility of the result was demonstrated by the simulation. The result indicated that with the mass increased only by 0.18%, the first four natural frequencies of the optimal crossbeam were increased by 19.56%, 19.45%, 19.84%, 17.05%.

Background and Objective: Biliary atresia (BA) is a destructive inflammatory obliterative cholangiopathy of neonates that affects both intrahepatic and extrahepatic bile ducts. Although the etiology is unknown, immunologically mediated injury of the bile ducts triggered by as yet unidentified infectious agents is likely to play a critical role. Interleukin-18 (IL-18) is a proinflammatory cytokine that plays an important role in immune, infectious, and inflammatory diseases because of its induction of interferon-gamma. In this study, we investigated whether polymorphisms of the IL18 gene were associated with susceptibility to BA. Patients and Methods: Genomic DNA was extracted from whole-blood samples of 50 Taiwanese children with BA and 1117 ethnically matched healthy controls. The IL18 ―1297 T/C, ―607 C/A, ―137 G/C, and +105 A/C polymorphisms were genotyped using the TaqMan assay. Results: No statistically significant differences of genotype, allele, carrier, and haplotype frequencies of these IL18 gene variants were found between children with BA and healthy controls. Conclusions: Our data suggest that the IL18 gene does not play a major role in BA predisposition in Taiwanese children.

Background/Purpose Sphingomonas paucimobilis is a glucose-nonfermenting Gram-negative bacillus that is widely distributed in both natural environment and hospitals. Various infections in humans have been reported, but most have been limited to sporadic case reports. The aim of this study was to describe the clinical characteristics and manifestations of S. paucimobilis bacteremia. We also reviewed the literature on S. paucimobilis bacteremia. Methods Cases of S. paucimobilis bacteremia were identified retrospectively at a university-affiliated hospital in Taiwan. In addition, relevant case reports were identified through PubMed and reviewed. Results From April 2004 to April 2008, 42 cases of S. paucimobilis bacteremia were identified in this study. Among them, 16 cases were identified from E-Da hospital, Kaohsiung, Taiwan and 26 cases from the literature review. The median age of patients was 48.5 years and 57.1% were male. The most common comorbidities included malignancy (57.1%), immunosuppressant use (40.5%), and diabetic mellitus (11.9%). Hospital-acquired bacteremia accounted for 69.0% of infections. Primary bacteremia and catheter-related bloodstream infection were found in 35.7% and 33.3% respectively. The most effective antibiotics were fluoroquinolones, carbapenems, and β-lactam/β-lactamase inhibitor combinations. All 42 patients survived the S. paucimobilis bacteremic episodes, but three patients experienced septic shock. Conclusion S. paucimobilis can cause infections in healthy as well as immunocompromised individuals. Although it is an organism of low clinical virulence, infection caused by S. paucimobilis can lead to septic shock. Further clinical research is required to characterize this infection.

Kawasaki disease (KD) is a systemic vasculitis caused by unknown infectious agents, host immune dysregulation and genetic susceptibility in children. Coronary artery lesions (CALs) complicate 15-25% of cases of untreated KD. The aim of this study was to investigate if the single-nucleotide polymorphism (SNP) rs28493229 of the ITPKC gene is associated with susceptibility to KD or with CALs in Taiwanese children. A total of 385 unrelated Taiwanese children (222 boys and 163 girls) with KD were included, 140 of whom had CALs. Mean age at diagnosis was 1.9 +/- 1.7 (0.1-10.2) years. Rs28493229 was genotyped in children with KD and 1158 ethnically matched healthy controls using the TaqMan Allelic Discrimination Assay. In 184 families with KD, both biological parents were available, constituting 184 trios with their children. They were assessed in a family-based study by means of a transmission/disequilibrium test (TDT). No significant differences in genotype (P = 0.29 and P = 0.29, respectively), allele (P = 0.14 and P = 0.22, respectively) and carrier (P = 0.22 and P = 0.25, respectively) frequencies of the SNP were found between healthy controls and children with KD or those with CALs. TDT in the 184 family trios and in 69 trios where the child had CALs did not reveal significant overtransmittion of the C allele. In conclusion, we did not find a statistically significant association between the ITPKC gene SNP rs28493229 and KD or CALs in Taiwanese children.

Processing precision of numerical control machine tool is decided by static rigidity and dynamic rigidity of spindle to a great extent. 3- D model of numerical control machine tool was established by using parametric modeling and virtual assembly function of Solidworks. Simultaneously, simulation and Experiment study of the spindle static rigidity was carried out, and practicability of the simulation analysis method was proved. The result indicates that the biggest deformation appears in the front of spindle. The static rigidity of spindle can been enhanced greatly by enhancing three carriage-feed system’s static rigidity of machine tool. The simulation for the dynamic rigidity of spindle indicates that the dynamic rigidity of spindle is uniformly distributed and resonance can be avoided effectively by the spindle when working.

Biliary atresia (BA) is a devastating neonatal hepatobiliary disease characterized by bile duct inflammation and fibrosis. The pathogenesis remains unclear, but immunologically mediated injury to bile ducts following an infectious insult is likely to play a critical role. Interferon-gamma (IFN-gamma) is a key cytokine that affects immune-mediated inflammatory responses.This study aims to investigate whether polymorphisms of the IFN-gamma (IFNG) gene were associated with susceptibility to BA.The IFNG -1615 C/T, -183 G/T, +874 A/T, and +2197 A/G polymorphisms were genotyped using the TaqMan assay, and CA repeat microsatellite was analyzed using capillary electrophoresis in 50 children with BA and 788 ethnically matched healthy controls.The distribution of genotype, allele, and haplotype frequencies of these IFNG gene variants did not differ significantly between children with BA and controls.Polymorphisms of the IFNG gene do not appear to play a major role in the genetic predisposition to BA in Taiwanese children.

Designing a flexible fixture is much more complicated. In this paper a collaborative environment was introduced for flexible fixture design. The tasks involved in fixture design are analyzed and decomposed into five subtasks, which are assigned to workgroups by a project manager. The workgroups can be distributed in different departments or in different locations geographically. The framework of collaborate design environment is constructed. Each workgroup is responsible to a certain job. However, the information needed for flexible fixture design is shared among these workgroups. The information exchanging and management in the environment are expressed with a block diagram. Finally, an example of flexible fixture for manufacturing a thin-walled workpiece is employed to illustrate the efficiency of the collaborative environment.

Thin-walled workpiece is prone to produce deformation in the process of machining because of cutting and clamping forces. In this paper, a model of cutting parameters optimization is proposed to control the deflection. The influence of deflection on nominal milling depth is taken into account and the machining deflection is computed by iterative method. Based on the optimization model, a prototype system is developed to optimize the cutting parameters for a thin-walled workpiece with the genetic algorithm and finite element method. Finally, a simulation example is used to demonstrate the feasibility of the cutting parameters optimization method. The simulation result can be further employed into practical machining situation.

Fluoroquinolone-nonsusceptible Streptococcus pyogenes has rapidly emerged in several countries. The aim of this study was to survey the epidemiology and molecular characteristics of fluoroquinolone-nonsusceptible S. pyogenes in Taiwan. A total of 350 consecutive S. pyogenes isolates were collected between January 2005 and December 2012, including 152 (43.4%) invasive and 198 (56.6%) noninvasive isolates. Thirty-nine isolates (11.1%) of S. pyogenes were nonsusceptible to fluoroquinolones, including one emm1/ST28, 4 emm4/ST39, 33 emm12/ST36, and 1 emm87/ST62. Of all the isolates, emm12 (50%) demonstrated the highest prevalence of fluoroquinolone nonsusceptibility. Alterations of Ser79Phe and Ala12Val in ParC were the most frequently mutations in fluoroquinolone-nonsusceptible S. pyogenes isolates. There were no amino acid substitutions in GyrB, and 1 emm87 isolate exhibited 3 nonsynonymous mutations in ParE. Our study reveals the emergence of fluoroquinolone-nonsusceptible S. pyogenes emm12/ST36 in Taiwan. Regular surveillance of fluoroquinolone susceptibility in S. pyogenes is suggested.

To study the effect of extract of Radix Tetrastigma hemsleyani on the proliferation and apoptosis of human lung carcinoma H1299 cells, and to explore its mechanisms. METHODS H1299 cells were treated with the extract of Radix Tetrastigma hemsleyani in different concentrations at different time points. Its inhibition on H1299 cell proliferation was detected by Cell Counting Kit-8 (CCK-8) assay. The morphology of the H1299 cell was observed by inverted microscope. Changes of apoptosis were observed by Hoechst33258 methods. The apoptosis rate was detected by flow cytometry. Expression changes of apoptosis-related proteins pro-caspase-3, pro-caspase-9, cle-caspase-3, cle-caspase-9, and poly-ADP-ribose polymerase (PARP) were detected by Western blot.Compared with the control group, the inhibition rate of H1299 cells increased after acted by 0.5, 1, 5, and 10 mg/mL extract of Radix Tetrastigma hemsleyani (P0.05, P0.01). The longer the acting time, the higher the inhibition rate (P0.01). Under inverted microscope, typical morphological changes could be seen and the number of H1299 cells was reduced. Under fluorescence microscope, dark stained nucleus and formed apoptotic body could be observed. Results of flow cytometry showed that the apoptosis rate was obviously dose-effect correlated with the concentration of extract of Radix Tetrastigma hemsleyani. Results of Western blot indicated that compared with the control. group, the protein expression of pro-caspase-3, pro-caspase-9, and PARP were down-regulated and that of cle-caspase-3, cle-caspase-9, and cle-PARP were up-regulated by 5 and 10 mg/mL extract of Radix Tetrastigma hemsleyani (P0.05).Extract of Radix Tetrastigma hemsleyani had obvious effect in inhibiting the proliferation and inducing apoptosis of human lung carcinoma H1299 cells, which might be achieved by activating the expression of caspase protein.

Having first defined the helical angle as the angle between the cutting edge and the axis of rotation of the cutter, this paper then presents design models for producing the cutting edge and groove of a ball-end cutter with concave-arc generator. The relative feed speeds of the grinding wheel in the radial and axial directions during NC machining of the cutter are derived based upon a given speed of rotation. The feed speed of the grinding wheel in the radial direction is modified according to the cross section of the groove that passes through the center of the cutter sphere. The paper presents a method for manufacturing a concave-arc ball-end (CABE) cutter using a 2-axis NC machine. The models that are used to calculate the actual obtained groove and the computer simulation method are also included. To further enhance the accuracy of the mathematical models, a compensatory machining process that eliminates residual profile on the revolving surface is presented. This paper provides a valuable reference for the design and machining of this cutter type.

This paper presents models for defining the minimum circumscribed cylinder (MCC) of the cutter shank, the minimum circumscribed circular-arc-type revolving surface (MCCRS) and the minimum circumscribed corner arc revolving surface (MCCARS) with a spiral groove. A systematic modeling procedure is presented for the assessment of the contour quality of the circular-arc end milling (CAEM) cutters with a cylindrical shank. The axis of the MCC of the cylindrical shank of a revolving cutter with a circular-arc generator curve and a corner radius is taken as the datum line. The profile tolerances and errors are estimated. The presented models are all illustrated and verified by example. This approach can be generalized to a cutter with more than two circular arcs in its shape profile. The paper provides a valuable reference for the evaluation of the actual contour quality of this type of revolving cutter.

The paper presents a systematic manufacturing model for producing the circular-arc ball-end milling (CABEM) cutter. Having first defined the helical angle as the angle between the cutting edge and the axis of rotation of the cutter, the geometric shapes of helical grooves and cutting edge profiles are analytically derived. The feed speed of the grinding wheel in the radial direction is modified according to the cross-section of the groove that passes through the centre of the cutter sphere. The models that are used to calculate the actually obtained groove, and the method of computer simulation are also included. To further enhance the accuracy of the mathematical models, a compensatory machining process, which eliminates residual profile on the revolving surface, is also presented.

The toroid-shaped helical cutter with an involute generator is a precision tool used in the machining of involute helical gears. Taking the axis of the minimum circumscribed cylinder of the measured points on the cylinder shank as the datum axis, this paper provides models of the minimum circumscribed involute revolving surface and the minimum circumscribed toroid-shaped revolving surface. This paper also presents models for evaluating the contour quality of a toroid-shaped cutter with an involute generator. The validity and accuracy of these models are confirmed by worked examples.

Outer cycloid gears are used widely in many instruments and machines. The outer cycloid slotting cutter is an important cutting tool used in the manufacturing of this type of gear. In the process of design, the ideal outer cycloid cutter is one where a cylindrical surface takes the tooth profile of the outer cycloid as the directrix. However, during the manufacturing process, it is used as a cutter and therefore a cutting edge is required. As a result, it will be seen that the processes of design and usage of the outer cycloid cutter are not the same. The range of the qualified length of tooth is deduced in this paper by using the mid-point and mid-line method. This paper also presents the associated outer cycloid slotting cutter design and manufacturing models so that the modelling accuracy and the necessary relief angles of the top cutting edge and side cutting edge can be ensured. This paper is intended as a reference to be used in the manufacture and application of this type of slotting cutter.

This paper presents a systematic modelling procedure for assessing the profile quality of concave-arc ball-end (CABE) milling cutters with a cylindrical shank. CABE milling cutters are widely used in three-axis numerical control (NC) machines for producing dies and moulds of complicated surface features. Evaluation of the contour quality of the CABE milling cutter is crucial in enhancing machining accuracy and efficiency. In order adequately to describe the shape of the clamped cutter, the centre-line axis of the minimum circumscribed cylinder of the cylinder shank is taken as the referenced datum axis. The minimum circumscribed concave-arc revolving surface and the minimum circumscribed spherical surface are carefully derived in sequence. The profile errors and tolerances are estimated. The quality of the CABE milling cutter is assured by using the proposed modelling procedure, and several numerical examples are presented to illustrate its effectiveness. The results indicate that the present method is feasible and can be extended to enhance the quality of various revolving cutters.

The paper presents a geometric modelling approach for the precision design and NC machining of a concave-arc ball-end milling (CABEM) cutter which is an important tool for mould-making industries. This paper presents systematic models of the cutting edge, helical groove, and grinding wheel design for the NC machining of a CABEM cutter. Both the normal to the revolving axis and the tangent to the groove, are used to derive the required precision sectional profiles of the grinding wheel. In compliance with the maximal sectional radius of the cutter, the profile of the groove section and both the radial and axial cutting speeds of the grinding wheel are computed in sequence. Using the computer simulation results of the groove actually obtained, this paper proposes a method to resolve the problems of the residual revolving surface and the narrow cutting edge strip. This paper is intended to serve as a reference for the design and NC machining of cutters of this type.

This paper presents models for evaluating the contour quality of a toroidal cutter with a concave-arc generator and a cylindrical shank. Taking the axis of the minimum circumscribed cylinder of measured data on the cutter shank as the datum axis, models are developed to investigate the minimum circumscribed concave-arc revolving surface and the minimum circumscribed toroidal revolving surface. Illustrative examples are given to verify the validity of these models. This paper provides a reference for evaluating the contour quality of this type of revolving cutter.

The paper presents a systematic modelling approach for precision design and numerical control (NC) machining of the tapered ball-end milling (TBEM) cutter that has emerged as a powerful tool for mould-making industries. The major contribution of this work is to produce a complete cutting edge that was conventionally neglected or oversimplified near the ending portion interfacing with the tapered ball end. In order to comply suitably with the requirement for a specific rotating speed, both radial and axial cutting speeds are carefully derived by using a given helical angle defined as the angle between the cutting edge and the revolving axis. Both projected profiles, one normal to the revolving axis and the other tangential to the groove, are used to produce precision sectional profiles of the grinding wheel. In compliance with maximal sectional radius of the taper, the profile of the groove section and the feeding speed of the grinding wheel are computed in sequence. By means of a two-axis NC machine, the shape of the TBEM cutter that possesses a nearly constant helical angle can be systematically designed and produced. With a slightly remedial grinding procedure at the ball end, the dimensional accuracy of the groove and the cutting edge of the TBEM cutter can be well controlled.

This paper presents mathematical models of the cutting edge and helical groove, and the design of the grinding wheels for use in the NC machining of toroid-shaped cutters with a concave-arc generator. According to computer simulation results of the groove actually obtained, the problems of residual profile errors on the groove surface and the cutting edge curve are presented, and rectification action is proposed. This paper provides a reference for the design and NC machining of this type of cutter.

This paper introduces the differences in quality evaluation for the sampling inspection of drills with taper or cylindrical shanks. For a drill with a taper shank, the datum axis is taken to be the axis of the minimum circumscribed cone, whereas for a drill with a cylindrical shank, the datum axis is taken to be the axis of the minimum circumscribed cylinder. The features that are common to both drill types are the definition of the minimum circumscribed cylinder of the cylinder part with helical grooves and the minimum circumscribed univalent hyperboloid based upon the datum axes given above. This paper presents all the necessary supporting models, illustrated and verified by examples, for the evaluation of actual contour quality for these two drill types which are comprised of compound surfaces.

The void structures and related optical properties after thermal annealing with ambient oxygen in regularly patterned ZnO nanrorod (NR) arrays grown with the hydrothermal method are studied. In increasing the thermal annealing temperature, void distribution starts from the bottom and extends to the top of an NR in the vertical (c-axis) growth region. When the annealing temperature is higher than 400°C, void distribution spreads into the lateral (m-axis) growth region. Photoluminescence measurement shows that the ZnO band-edge emission, in contrast to defect emission in the yellow-red range, is the strongest under then-ZnO NR process conditions of 0.003 M in Ga-doping concentration and 300°C in thermal annealing temperature with ambient oxygen. Energy dispersive X-ray spectroscopy data indicate that the concentration of hydroxyl groups in the vertical growth region is significantly higher than that in the lateral growth region. During thermal annealing, hydroxyl groups are desorbed from the NR leaving anion vacancies for reacting with cation vacancies to form voids.