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Experiments are conducted to explore the rolling of a cylinder over a pool of viscous fluid. The speed, width and loading of the cylinder are varied along with the initial depth and length of the viscous pool. Depending on the conditions, the cylinder will either ride on a lubrication film or remain in solid contact with the underlying substrate. For the former situation, a lubrication theory is presented that describes the pressure underneath the cylinder and the thickness of the film. The theory approximates the flow by the one-dimensional Reynolds equation with the addition of one term, with an adjustable parameter, to account for the flux of fluid to the cylinder sides. Once this parameter is calibrated against experiment, the theory predicts peak lubrication pressures, gap sizes and film thicknesses to within approximately ten per cent. For lubricated rolling, the film splits evenly between the cylinder and substrate downstream of the nip. The printer's instability arises during the splitting process, patterning the residual fluid films on the substrate and cylinder. If the pool length is less than the cylinder circumference, the fluid adhering to the cylinder is rotated back into contact with the substrate, and when there is sufficient adhered fluid a lubrication film forms that can again be modelled by the theory. Conversely, if there is insufficient adhered fluid, no contiguous lubrication film is formed; instead, the pattern from the printer's instability ‘prints’ from the cylinder to the substrate.
Our objective was to quantify the cross-sectional associations between dietary fatty acid (DFA) patterns and cognitive function among Hispanic/Latino adults. This study included data from 8,942 participants of the Hispanic Community Health Study/Study of Latinos, a population-based cohort study (weighted age 56.2 y and proportion female 55.2%). The NCI (National Cancer Institute) method was used to estimate dietary intake from two 24-hr recalls. We derived DFA patterns using principal components analysis with 26 fatty acid and total plant and animal monounsaturated fatty acid (MUFA) input variables. Global cognitive function was calculated as the average z-score of 4 neurocognitive tests. Survey linear regression models included multiple potential confounders such as age, sex, education, depressive symptoms, physical activity, energy intake, and cardiovascular disease. DFA patterns were characterized by consumption of long-chain saturated fatty acids (SFA), animal-based MUFA, and trans fatty acids (Factor 1); short to medium-chain SFA (Factor 2); very-long-chain omega-3 polyunsaturated fatty acids (PUFA) (Factor 3); very-long-chain SFA and plant-based MUFA and PUFA (Factor 4). Factor 2 was associated with greater scores for global cognitive function (β=0.037 ± 0.012) and the Digit Symbol Substitution (DSS) (β=0.56±0.17), Brief Spanish English Verbal Learning-Sum (B-SEVLT) (β=0.23 ± 0.11), and B-SEVLT-Recall (β=0.11 ± 0.05) tests (P<0.05 for all). Factors 1 (β=0.04 ± 0.01) and 4 (β=0.70 ± 0.18) were associated with the DSS test (P<0.05 for all). Consumption of short to medium-chain SFA may be associated with higher cognitive function among U.S.-residing Hispanic/Latino adults. Prospective studies are necessary to confirm these findings.
Pulmonary atresia with ventricular septal defect and severe tetralogy of Fallot require a palliative procedure for pulmonary artery rehabilitation. For first-stage palliation, two main surgical options are still debated: right ventricle to pulmonary artery connection and modified Blalock–Taussig shunt. We compared the clinical outcomes of the two procedures.
From 1995 to 2018, 88 patients needed palliation (pulmonary atresia with ventricular septal defect n = 47; tetralogy of Fallot n = 41). Among these patients, 70 modified Blalock–Taussig shunt and 18 transannular path augmentation were performed before 6 months of age. Using a 1:1 propensity score match analysis, 20 patients were included in the analysis. The primary outcome was in-hospital mortality and pulmonary artery growth.
After matching, the pre-operative Nakata was smaller in transannular path augmentation 54 ± 24 mm2/m2 than modified Blalock–Taussig shunt 109 ± 31 mm2/m2 (p < 0.001). The age and weight were similar (p = 0.31 and p = 0.9, respectively). There was no difference in in-hospital mortality (p = 0.3). The Nakata index before biventricular repair and delta Nakata were smaller in modified Blalock–Taussig shunt group (206 ± 80 mm2/m2, 75 ± 103 mm2/m2) than transannular path augmentation (365 ± 170 mm2/m2, 214 ± 165 mm2/m2; p = 0.03; p < 0.001). Median time to biventricular repair was similar (p = 0.46). The rate of interstage reintervention was similar (p = 0.63).
The transannular path augmentation is better for the rehabilitation of the native pulmonary artery. Despite a smaller pulmonary artery, right ventricle to pulmonary artery connection is equivalent to modified Blalock–Taussig shunt for rate of biventricular repair and time to biventricular repair.
Plant proteinase inhibitors are among the promising biopesticides which are induced in plants tissues against the several Lepidoptera pests to inhibit digestive proteases. In this study, protein extracts of two nonhost plant seeds, Amaranthus retroflexus Linnaeus (Amaranthaceae) and Cuminum cyminum Linnaeus (Apiaceae), were examined on Helicoverpaarmigera (Hübner) (Lepidoptera: Noctuidae). The results obtained by using azocasein as a substrate showed that inhibitory activity of general proteases of the larvae fed on a diet incorporated with both inhibitors was dose dependent. Seed extracts of A. retroflexus and C. cyminum at the highest concentration showed that inhibition activities of chymotrypsin-like proteinase and trypsin-like proteinase were between 31–45% and 28–61%, respectively. Based on polyacrylamide gel electrophoresis, all of the proteinase isoforms, including those of A. retroflexus seed extracts, disappeared entirely, and only one band was detected in the seed extracts of C. cyminum. Larval mortality in the larvae fed on A. retroflexus and C. cyminum seed extracts was 56 ± 2.15 and 68 ± 2.23, respectively, but mortality in control (no seed protein extract) was 12 ± 2.34 individuals. Also, the life table parameters were affected significantly by A. retroflexus and C. cyminum protein seed extracts. Therefore, A. retroflexus and C. cyminum seed protein extracts showed inhibitory effect on H. armigera digestive proteinases and adverse effects on survival and fitness of the pest; hence, they could be introduced as a successful biopesticide in the near future.
REM sleep behaviour disorder (RBD) is associated with psychiatric symptoms, such as anxiety and depression. RBD is characterized by loss of normal skeletal muscle atonia during rapid eye movement (REM) sleep with prominent motor activity and dreaming and is a usual symptom of the early stages of Parkinson's disease (PD). Diffusion MRI connectometry was used to carry out group analysis between age and gender matched PD patients with RBD in with and without depression to characterize possible depression-related white matter microstructural changes in the Parkinson patients with RBD.
DWI images were obtained for 15 PD-RBD with depression and 27 PD-RBD without depression. This dataset was acquired on a 3 Tesla Siemens scanner, producing 64 DWI at b = 1000 s/mm2 and one b0 image. Diffusion MRI data were corrected for subject motion, eddy current distortions, and susceptibility artefacts due to the magnetic field inhomogeneity. Diffusion MRI connectometry was conducted in a total of 27 subjects using percentage measurement.
PD-RBD Patients with depressive symptoms showed decreased anisotropy (FDR < 0.05) in the fornix bilaterally, right cingulum, inferior longitudinal fasciculus bilaterally, right corticospinal tract and Genu of corpus callosum compared to PD-RBD patients without depression.
Since RBD is considered to be an early symptom of PD and also a marker of progression to PD, these results might PD-RBD patients with depression may progress dementing processes and visuospatial dysfunction earlier since fornix, cingulum and ILF have proven to be associated with these cognitive dysfunctions respectively.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
The robotic intervention has great potential in the rehabilitation of post-stroke patients to regain their lost mobility. In this paper, firstly, we present a design of a novel, 7 degree-of-freedom (DOF) upper limb robotic exoskeleton (u-Rob) that features shoulder scapulohumeral rhythm with a wide range of motions (ROM) compared to other existing exoskeletons. An ergonomic shoulder mechanism with two passive DOF was included in the proposed exoskeleton to provide scapulohumeral motion with corresponding full ROM. Also, the joints of u-Rob have more range of motions compared to its existing counterparts. Secondly, we propose a fractional sliding mode control (FSMC) to control u-Rob. Applying the Lyapunov theory to the proposed control algorithm, we showed the stability of it. To control u-Rob, FSMC has shown effectiveness to handle unmodeled dynamics (e.g. friction, disturbance, etc.) in terms of better tracking and chatter compared to traditional SMC.
This paper addresses the application of a novel elimination algorithm with a newly developed homotopy continuation method (HCM) for forward kinematics of a specific hybrid modular manipulator known as n-(6UPS). First, the kinematic model of n-(6UPS) was extracted using a homogenous transformation matrix method. Then, a novel algebraic elimination algorithm was developed to transform the highly nonlinear proposed kinematic model into a system of polynomial equations for each module. Next, the HCM is considered to solve the system of equations. Comparison of the results from the proposed approach with experimental data and other methods demonstrates the efficiency of the proposed contribution.
Unstable shear layers in environmental and industrial flows roll up into a series of vortices, which often form complex nonlinear merging patterns such as pairs and triplets. These patterns crucially determine the subsequent turbulence, mixing and scalar transport. We show that the late-time, highly nonlinear merging patterns are predictable from the linearized initial state. The initial asymmetry between consecutive wavelengths of the vertical velocity field provides an effective measure of the strength and pattern of vortex merging. The predictions of this measure are substantiated using direct numerical simulations. We also show that this measure has significant implications in determining the route to turbulence and the ensuing turbulence characteristics.
In the present paper, a general analytical solution is proposed for anisotropic heat conduction through truncated composite spherical shells. The solution is so important in designing the spherical vessels which are usually used to store the CNG, LNG, LPG and other petroleum condensates. Herein, it is supposed that the fiber angle of composite laminate is in range of zero to 90 degrees. Heat convection with ambient flow, an external heat radiation, and a possible internal heat generation are modeled within the heat transfer equation. The exact solution is derived using the complex finite Fourier transform method. The particular solution of transferred equation is found based on the Green’s function and Sturm-Liouville theories. Finally, an inverse integral transformation is applied to form the final analytical solution in physical space. Defining four materials differing in the value of conductivity coefficient in fiber direction, the effects of used composite material and fiber angle on temperature distribution of the spherical shell are investigated in detail.
Employing an analytical method, non-linear low-velocity impact response of carbon nanotube (CNT)-reinforced sandwich cylindrical panels in thermal environments is analysed. Two types of core (i.e. homogenous and functionally graded) are considered for sandwich panels. The face sheets of sandwich panels are multi-layer which consist of CNT-reinforced composite (CNTRC) and metal layers. Micromechanical models are used to estimate the material properties of CNTRCs. A higher-order shear deformation theory with a von Kármán-type of kinematic non-linearity provides the equations of motion. Temperature-dependent material properties are used to include the thermal effects. The equations of motion are solved using a two-step perturbation technique. Existing numerical results in the literature are used to validate the present method. The effect of nanotube volume fraction, material property gradient, impactor initial velocity, geometrical parameters of cylindrical panel, temperature change and edge boundary condition on the impact response of cylindrical panel structures is discussed. The quantitative results and analytical formulations can be helpful in better designing of CNTRC structures subjected to low-velocity impact in thermal environments.
Surprise best seller fails to capture the triumph of azar nafisi's reading lolita in tehran (2003). This “memoir in books” recounting the cultural politics of postrevolutionary Iran—not exactly the subject matter that typically sends a book to the top of the literary charts—turned out to be “a bookseller's dream” (Burwell 143). It sold millions, was translated into thirty-two languages, and—perhaps most impressively—generated a critical lovefest that united neocon hawks like Bernard Lewis with progressive luminaries like Margaret Atwood. Far less surprising, however, was the familiar canard of “Oriental darkness” dominating the book's mainstream reception: the idea that non-Westerners have no literature of their own and know nothing about the Western canon. Many commentators refused to consider the radical possibility that Iranians may have already been acquainted with some canonical occidental texts. Nowhere to be found in this discussion was the name Ibrahim Younisi (1926-2012), whose fifty-year career in literary translation underscores that Iranians have long been avid readers and enthusiastic translators of world literature. Sadly, this ignorance is not limited to mainstream literary publications; John O. Jordan and Nirshan Perera's Global Dickens fails to mention that Charles Dickens's works have been in widespread circulation in Iran since the 1960s. Decades before Nafisi supposedly led her students to Western literary civilization, Younisi had translated not just Dickens but also Thomas Hardy, Henry Fielding, Shakespeare, and George Eliot. By the time of his death, Younisi's résumé included more than seventy translations, encompassing literary texts, criticism, memoir, and historical scholarship.
This study analyses the epidemiologic, clinical and molecular findings of all culture-confirmed cases of listeriosis notified from 2010 to 2015 in the Tel Aviv District, which is known to have high rates of listeriosis. All clinical isolates of Listeria monocytogenes were subtyped using two-enzyme pulsed-field gel electrophoresis. During the studied period, 102 cases of listeriosis were notified, including 23 pregnancy-associated cases (23%). Among 79 non-pregnancy-associated cases, 18 had neuro-invasive disease (21%). There were 26 deaths associated with the disease. Using molecular identification, we found a number of clusters of identical bacterial clones, which pointed to possible sources of infection. The high rates of morbidity and mortality resulting from listeriosis, as well as the diverse ways of infection demonstrated in this study, accentuate the need to boost public health actions, in order to raise awareness and better control high-risk contamination routes.