4D printing shape memory polymers for dynamic jewellery and fashionwear

4D printing is a novel approach that enables dynamic functionality in ordinary static object. We used a methacrylated semicrystalline polymer to print objects exhibiting thermally triggered shape memory behaviour. By exploring various molecular weights, it was found that a methacrylated polycaprolactone polymer with a number average molecular weight of 10,000?g?mol^?1 exhibited the best thermal and mechanical behaviour. The effect of dyes’ addition to the ink formulation on the photopolymerisation and on the printing processes was evaluated. The ink was utilised for demonstrating fabrication of dynamic jewellery and a shoe accessory by Digital Light Processing printing.     

Pseudogap Behavior in the Electronic Specific Heat of La2−xSrxCuO4

In La214, the electronic specific heat coefficient (=C _el /T) is gradually suppressed with lowering T below a certain temperature T* (> T _c ), where the in-plane resistivity and magnetic susceptibility also tend to be suppressed slightly. Temperature T*, increasing with lowering x, is in qualitative agreement with the mean field T _c (T _co ), estimated from the superconducting gap amplitude 2 _o at T T _c , as the onset temperature T* of a pseudogap in Bi2212. The gradual suppression of below T _co implies that a pseudogap will also open up below T _co in La214 as in Bi2212. In underdoped samples, whose pseudogap-like behaviors in C _el(T) become marked, the anomaly of C _el around T _c is rather different from the BCS expectation.     

Intel's incident-free culture: a case study

The occupational ergonomic program that Intel's newly established manufacturing plant in Israel implemented in 1997 helped prevent injuries and also marked the launch of a whole new approach to ergonomics. A key element in the success of the seven-point program was a strong commitment from management, which came to regard this plan as a vital strategic element in the new plant's success. Comprehensive, top-down planning imposed obligations on all elements in the manufacturing spectrum, from suppliers to contractors to employees. Work requirements were set; cooperation with the plant's occupational health professionals was established; and long-term reporting and instruction systems were developed. Extensive ergonomic training was a crucial factor in integrating ergonomic procedures into the organization's day-to-day activities. Along with this instructional program, ergonomic engineers implemented a strict measuring system to ensure that each ergonomic activity would be performed according to schedule. By the time the factory opened its gates and began to produce, a vigorous ergonomic environment had emerged and employees were displaying an ergonomic mindset that also impinged upon their non-work activities. As a result of the successful implementation of the program, Intel's ergonomic program has become a model for Israeli industry. This paper presents a full ergonomic program that besides supplying the Intel plant with solutions was unique enough to impact the whole Israeli industry.     

The effectiveness of a training method using self-modeling webcam photos for reducing musculoskeletal risk among office workers using computers

An intervention study was conducted to examine the effectiveness of an innovative self-modeling photo-training method for reducing musculoskeletal risk among office workers using computers. Sixty workers were randomly assigned to either: 1) a control group; 2) an office training group that received personal, ergonomic training and workstation adjustments or 3) a photo-training group that received both office training and an automatic frequent-feedback system that displayed on the computer screen a photo of the worker's current sitting posture together with the correct posture photo taken earlier during office training. Musculoskeletal risk was evaluated using the Rapid Upper Limb Assessment (RULA) method before, during and after the six weeks intervention. Both training methods provided effective short-term posture improvement; however, sustained improvement was only attained with the photo-training method. Both interventions had a greater effect on older workers and on workers suffering more musculoskeletal pain. The photo-training method had a greater positive effect on women than on men.     

Mean shift trackers with cross-bin metrics

Cross-bin metrics have been shown to be more suitable than bin-by-bin metrics for measuring the distance between histograms in various applications. In particular, a visual tracker that minimizes the earth mover's distance (EMD) between the candidate and reference feature histograms has recently been proposed. This tracker was shown to be more robust than the Mean Shift tracker, which employs a bin-by-bin metric. In each frame, the former tracker iteratively shifts the candidate location by one pixel in the direction opposite to the EMD's gradient until no improvement is made. This optimization process involves the clustering of the candidate feature density in feature space, as well as the computation of the EMD between the candidate and reference feature histograms after each shift of the candidate location. In this paper, alternative trackers that employ cross-bin metrics as well, but that are based on Mean Shift (MS) iterations, are derived. The proposed trackers are simpler and faster due to 1) the use of MS-based optimization, which is not restricted to single pixel shifts, 2) abstention from any clustering of feature densities, and 3) abstention from EMD computations in multidimensional spaces.     

New, Highly Accurate Propagator for the Linear and Nonlinear Schr?dinger Equation

A propagation method for the time dependent Schr?dinger equation was studied leading to a general scheme of solving ode type equations. Standard space discretization of time-dependent pde??s usually results in system of ode??s of the form 0.1 $$u_t - G u =s$$ where G is a operator (matrix) and u is a time-dependent solution vector. Highly accurate methods, based on polynomial approximation of a modified exponential evolution operator, had been developed already for this type of problems where G is a linear, time independent matrix and s is a constant vector. In this paper we will describe a new algorithm for the more general case where s is a time-dependent r.h.s vector. An iterative version of the new algorithm can be applied to the general case where G depends on t or u. Numerical results for Schr?dinger equation with time-dependent potential and to non-linear Schr?dinger equation will be presented.     

Molecular alignment structure of dimeric liquid crystals

While an antiferroelectric liquid crystal (AFLC) with dimeric molecules which take a bent molecular structure may show the phase transition from the isotropic liquid to the chiral smectic-C AFLC () phase via the nematic (N) phase, it has not been obvious yet why the and N phases may coexist in the phase sequence of the dimeric AFLC medium. In this study, the molecular alignment structures of the N and the SmC_A phases of an achiral dimeric LC were researched in detail with a polarized Fourier transform infrared spectroscopy (FT-IR). The domain structure with two orientational directions is formed both in the SmC_A and N phase, and the occupation ratio of two types of domain does not change in the phase transition. Since their alignment structures are basically same except for the existence of layer structure, their phases may coexist in the phase sequence of the dimeric AFLC.     

Oxidative degradation of polyolefins. I. Thermal oxidative degradation of atactic polypropylene in solution

Atactic polypropylene was oxidized in solution with radical initiator in the absence and presence of metal catalyst to considerably high conversion over the temperature range of 70° to 125°C, and oxidation products and the change in molecular weight distribution were measured. The unoxidized polypropylene had no ultraviolet absorption at 253.7 nm, whereas the oxidized polypropylene showed distinct absorption over a wide range of molecular weights. It was found that oxygen was incorporated into the polymer chain as hydroperoxide, acid, carbonyl, and hydroxy groups. Much of the absorbed oxygen was found to be involved in smaller fraction of low molecular weight products. Although the average molecular weight of the oxidized polypropylene decreased significantly, the formation of low-boiling products was quite small.     

Heterogeneous effects of G-CSF and GM-CSF on cell growth and ara-C cytotoxicity in childhood leukemias which express myeloid markers

It is uncertain if acute lymphoblastic leukemia (ALL) cells expressing myeloid makers can respond to granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF). We investigated the effects of G-CSF (0.01 microgram/ml) and GM-CSF (0.01 microgram/ml) on [3H]thymidine (TdR) uptake, and the cytotoxicity of 1-beta-D-arabinofuranosylcytosine (ara-C) in leukemia cells from 17 pediatric patients. ALL cells without myeloid markers did not respond to G-CSF or GM-CSF. On the other hand, these cytokines enhanced the [3H]TdR uptake and cell growth, not only of AML cells but also of ALL cells expressing myeloid antigens. However, G-CSF and GM-CSF did not always enhance the growth inhibitory effect of the cell cycle specific drug ara-C when the cells were co-cultured with the drug. There was no relationship between cell growth and the amount of [3H]TdR incorporation or the intracellular ara-CTP level. These results indicate the heterogeneous effects of G-CSF and GM-CSF on cell growth and ara-C sensitivity in childhood leukemia cells.     

Development of a new method for simultaneously evaluating mucociliary clearance and pulmonary epithelial permeability in rabbit experiments by means of 18FDG, three-dimensional positron emission tomography and rectilinear scan

OBJECTIVE: To determine which types of kinin receptor are present in human bronchial epithelial cells we studied the capability of bradykinin to mobilize intracellular Ca2+ ([Ca2+]i) in a human bronchial epithelial cell line (16HBE cells). MATERIAL: Human bronchial epithelial cell line transformed with an original defective simian virus 40 (SV40). TREATMENT: Bradykinin (0.1 pM to 0.1 microM), des-Arg9 bradykinin (1 microM), des-Arg10) kallidin (1 microM), indomethacin (1 microM), phosphoramidon (1 microM), captopril (1 microM), des-Arg9-[Leu8]bradykinin (1 microM), HOE 140 (DArg-[Hyp3, Thi5, DTic , Oic8]-bradykinin) (1 microM), and NPC 16731 (DArg-[Hyp3, Thi5, DTic7, Tic8]-bradykinin) (1 microM). METHODS: The mobilization of [Ca2+]i was determined by the fura-2 method. Two sample Wilcoxon rank-sum (Mann-Whitney) test was used for statistical calculations. RESULTS: Bradykinin, but not the selective agonists for kinin B1 receptor des-Arg9 bradykinin and des-Arg10 kallidin, increased the mobilization of [Ca2+]i (EC50, 0.079+/-0.009nM) in 16HBE cells in a concentration-dependent manner. Pretreatment with the cyclooxygenase inhibitor indomethacin (1 microM) or the peptidase inhibitors, phosphoramidon (1 microM) or captopril (1 microM), did not affect the response to bradykinin. The kinin B1 receptor antagonist, des-Arg9-[Leu8]bradykinin (1 microM), was inactive. HOE 140 and NPC 16731, two selective antagonists of the kinin B2 receptor abolished the response to bradykinin (IC50 of HOE 140 and NPC 16731 were 0.52+/-0.037nM and 1.67 +/- 0.41 nM, respectively). CONCLUSIONS: The present data indicate the presence of kinin B2 receptors in the 16HBE cells.