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The ball-end milling cutter is widely used in the machining of various complex curved surfaces and grooves. In order to meet the machining requirements of SiCp/Al, the mathematical model of ball end milling cutter, grinding track of grinding wheel and parameters in the actual machining process are optimized, and the experiment of milling SiCp/Al is designed. The results show that the surface roughness processed by the grinding tool is small. In the process of milling SiCp/Al, the main wear position of ball end milling cutter is the flank. [ABSTRACT FROM AUTHOR]

Thrombin generation assays and activated partial thromboplastin time (aPTT)-based clot waveform analysis (CWA), are some examples of global coagulation assays. Each modality evaluates different aspects of the clot forming process to globally define haemostasis with exclusive measurement parameters. Data on CWA are emerging, but its performance against other haemostatic assays is yet to be ascertained. This study evaluates the correlation between aPTT-based CWA and CAT parameters across a range of INR in warfarin-treated patients. A prospective study consisting of patients on warfarin anticoagulation with varying INR levels. CWA and CAT were performed for the study subjects. 54 samples were included covering an INR range from 1.33–6.89, with a mean of 4.31 +/- 1.13. For CAT parameters, endogenous thrombin potential (ETP) and peak thrombin were assessed. Both unadjusted and adjusted (adjusted for final plateau transmittance) aPTT-based CWA were evaluated for parameters min1 (maximum velocity), min2 (maximum acceleration) and max2 (maximum deceleration). Peak thrombin showed significant correlation with all CWA parameters (min1: r = 0.435, P<0.001; min2: r = 0.485, P<0.001; max2: r = 0.578, P<0.001; adjusted min1: r = 0.734, P<0.001, adjusted min2: r = 0.693, P<0.001; adjusted max2: r = 0.751, P<0.001). ETP correlated significantly with all CWA parameters except unadjusted min1 (min1: r = 0.235, P = 0.087; min2: r = 0.326, P = 0.016; max2: r = 0.437, P<0.001; adjusted min1: r = 0.610, P<0.001, adjusted min2: r = 0.563, P<0.001; adjusted max2: r = 0.642, P<0.001). We demonstrated a modest correlation between CAT and CWA parameters. Adjusted CWA improved this correlation. These findings provide additional understanding of CWA and it's role in the evaluation of global haemostatic function. [ABSTRACT FROM AUTHOR]

The instantaneous cutting contact relationship between tool and workpiece is changing with the change of curvature profile of open blade impeller. This leads to a strong nonlinear characteristic of the dynamic cutting load change during the machining of this type of parts, which affects the machining accuracy of the blade. This paper proposes a method to predict the machining error of ball-end milling under dynamic load. This method considers the influence of the curvature change of blade profile. Based on the analysis of the instantaneous cutting contact of complex surface in ball-end milling, a prediction model of the instantaneous undeformed cutting thickness of ball-end milling under the influence of surface curvature changes is constructed. Based on this model, the correction of the prediction model of machining complex surface milling force is realized. The prediction of the machining error when the complex surface is thin-walled impeller is processed under dynamic load. Finally, the effectiveness and accuracy of the method are verified through ball-end milling experiments. The research can provide guidance for the control and compensation of milling machining errors of complex-shaped thin-walled open blade. [ABSTRACT FROM AUTHOR]

With the increasing number of oncology patients and the use of chemotherapeutic agents, tumour multidrug resistance is becoming more and more prevalent. The search for new tumour treatment strategies to overcome tumour multidrug resistance is urgent. In this study, we designed GSH and ROS dual-responsive tumour-associated macrophages (TAMs)-targeted nanoparticles (NPs) for the co-delivery of the clinical first-line anti-breast cancer chemotherapy drug paclitaxel (PTX) and baicalin (Bai), which re-educates TAMs to alter their phenotype. We synthesised oligohyaluronic acid-mannose-folic acid (oHA-Man-FA, HMF) and astragalus polysaccharide-dithiodipropionic acid-paeoniflorol (APS-S-Pae, ASP), two hybrid materials that can self-assemble in water to form hybrid nanoparticles (HP-NPs) co-loaded with paclitaxel and baicalin (HP-NPs@PTX/Bai). The experimental results show that our designed hybrid nanoparticles can be specifically released in the tumour microenvironment and deliver the antitumor drug PTX as well as Bai, which reshapes the phenotype of TAMs, to the tumour site. The hybrid nanoparticles not only effectively re-educated TAMs from M2 TAM to M1 TAM, but also ameliorated the cytotoxic side effects caused by free PTX and provided better tumour suppression than free PTX and HP. [ABSTRACT FROM AUTHOR]

A series of D-A-type CdIIX2L (X = Cl, Br, I) complexes with asymmetric structures was designed, synthesized, and fully characterized. Structural studies indicate that Cd(II) has five-coordination with three N from terpyridine and two halides to form distorted square pyramidal complexes. The stereostructure of the metal complexes effectively reduces interactions between the complex molecules avoiding fluorescence quenching of the metal complexes in the solid state. The Cd(II) complexes also showed strong two-photon absorption in the near-infrared range by aperture Z-scan technique using a femtosecond laser in the solid state, with excellent two-photon absorption coefficients. The band gaps of the complexes suggested that they have potential applications in semiconductor materials and may be useful in near-IR nonlinear optical materials. [ABSTRACT FROM PUBLISHER]

In the present work, sodium alginate (ALG) was degraded by heterogeneous phase acid degradation. The molecular weight distribution of ALG after degradation was close to homogenization. Then the blood bio-compatibility of ALG with different molecular weights (ALG-0h 50,075, ALG-0.5h 20,680, ALG-2h 13,170 and ALG-96h 1170 kDa) was evaluatedin vitroandvivo. The human umbilical vein endothelial cells were used to assess the cytotoxicity of ALGs, ALG-0.5h and ALG-2h exhibited greater increment in percentage of cell viability comparing with ALG-0h and ALG-96h. With increasing of molecular weight of ALG, the blood clotting time was shortened and the hemolysis rate was slightly decreased. The different degree aggregation of red blood cells (RBCs) was observed in the ALG with different molecular groups and ALG-0h caused a severe aggregation of RBCs. Hematology analysisin vivobehavior after intraperitoneal (i.p.) injection indicated ALG-0h could cause blood solidification. Above results provided a reference for molecular weight selection in different applications. [ABSTRACT FROM AUTHOR]

Two new lanthanide(III) complexes were designed and synthesized: DAS[M(TTA)4]–, (M = Sm [1], M = Eu [2]), each of them contained one trans-4-[4′-(N, N-dimethylamino)styryl]-N-methyl pyridinium (DAS) cationic moiety, four 2-thenoyltrifluoroacetone anions (TTA-), and one cationic lanthanide(III). Herein, the structures were confirmed by single-crystal X-ray diffraction analysis. The results revealed that the central lanthanide(III) atom was fashionable eight-coordinated with square-antiprismatic coordination environment. Meanwhile, the photophysical properties of1and2were investigated by fluorescence spectra. It was proposed that there was an antenna effect and the energy transfer took place from the DAS cationic moiety to lanthanide(III) ions. [ABSTRACT FROM PUBLISHER]

Abstract: Background: Modern medicine has created a need for innovative methods of training that create safe, proficient specialists with adequate experience, and who are fit for purpose in this new system. Patient safety and patient-focused care are central to current practice and promoted by the use of simulation, human factors, team-based, multidisciplinary and interspecialty training. An acknowledgement that postgraduate training occurs within the work environment underlies the need to create systems that support learning within the workplace. Supervision, protected time for adequate induction and the opportunity to be involved in workplace learning are the key. It is also important that robust mechanisms to assure the quality of postgraduate education are in place. Methods: Available reports were researched, and the particularities of anaesthetic training were outlined and summarised. Then, in a translational approach, we examined how to apply the lessons learned from anaesthesiological training to surgical training. Results: The trend towards reducing the working hours of junior doctors, whilst still providing excellent training, creates a need for innovative, efficient, concentrated training programmes, where trainers and trainees are engaged in a seamless, constant educational endeavour. Conclusion: Within this review we offer the system of anaesthetic training in the UK, and some of its recent changes, as a template to highlight themes in postgraduate education that exemplify this innovation and are transferable not only to surgery but across different specialties. [Copyright &y& Elsevier]

Cancers are often with spontaneous or therapeutic necrosis that could be utilized as a generic target for developing new treatments. The purpose of this study was to investigate the biodistribution and pharmacokinetics of radioiodinated hypericin (Hyp), a naturally occurring compound, after intravenous (i.v.) injection in a rat model of liver and muscle necrosis ( n = 42), and evaluate its necrosis affinity. Hyp was labeled with 131I with labeling efficiency >99%. After incubating in solution/rat plasma for 8 days, radiochemical purity of 131I-Hyp remained 98.1 and 97.1%, respectively, indicating good in vitro stability. SPECT-CT images at 24 h after i.v. injection of 131I-Hyp in rats with induced liver and muscle necrosis showed obvious tracer absorption in necrotic tissues. Biodistribution studies revealed that the percentage of the injected dose per gram of tissue (%ID/g) evolved from 1.9 %ID/g at 6 h, through a maximum 3.0 %ID/g at 12 h, to 1.0 %ID/g at 192 h in necrotic liver. Pharmacokinetics studies revealed that the terminal elimination half-life, total body clearance and area under the curve of 131I-Hyp were 32.7 h, 9.2 L/h/kg and 1.6 MBq/L*h, respectively. These results demonstrated that 131I-Hyp features a long blood circulation in animals and persistent retention in necrotic tissues. Therefore, 131I-labeled Hyp could be a broad-spectrum anti-tumor agent with a cost much cheaper relative to the biological agents such as monoclonal antibodies. [ABSTRACT FROM AUTHOR]

The article discusses the theory of needs in relation to research. There are several meanings of need. Phrases like "felt needs" or "unmet needs" are used often by people. The concept of need is examined with standards, numbers, social psychological variables, allocation, and relationship. Needs are generally joined with numbers because they are associated with authority.

The article presents an analysis of functional behavior in case of a disaster. To the few hundred people directly involved, the tornado spelled tragedy. But for many of the remaining million residents of the Kansas City Metropolitan Area it spelled excitement and entertainment. To the sociological observer, viewing the event as collective behavior, several latent functions of disaster appear. it is suggested here that the storm which descended upon the fringe of the city appeared to provide thousands of spring-fever stricken citizens with recreation, occupation, relaxation, and a sense of fulfillment, the kind of collective excitement which offers a welcome respite from the monotonous routine of urban living. The unanticipated and frequently unrecognized consequences of a disaster need not be dysfunctional from the perspective of all of the groups concerned. It is suggested below that there may be important latent functions of a disaster. For example, it would be difficult for anyone to admit to himself that he could find pleasure in the tragedy of others although this is apparently what happened.

In this note, a simple identity with some of its applications is given. [ABSTRACT FROM AUTHOR]

This paper presents a characterization of the exponential distribution in terms of the means of the left-truncated values of the random variable concerned. This characterizing property leads to the Cauchy equation just as in the case of the lack of memory characterization. While the latter characterization assumes somewhat less easily accessible information concerning the probability distribution, the former only requires more readily available information regarding the expected values. The present characterization will be particularly useful in testing exponentiality for a failure model. A similar characterization is given for the geometric distribution. [ABSTRACT FROM AUTHOR]