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Treatment of pancreatic cancer by inhibiting the aberrant activation of the survival signaling pathways has received considerable attention. We investigated the probable action of DHA on the suppression of cell proliferation in human pancreatic ductal adenocarcinoma (PDAC) cells. Our results demonstrated that DHA dose-dependently inhibited cell proliferation through an induction of cell cycle arrest in human PDAC cells. DHA suppressed the expression of phosphorylated-Rb (p-Rb), cyclin D1, cyclin E, cyclin A, E2F1 and c-Myc proteins. Blocking the activation of STAT3 signaling pathway led to an inactivation of CAMKII and increased phosphorylation of c-Myc (T58) protein accompanied with decreased expression of c-Myc protein. Treatment of DHA effectively inhibited cell survival through decreased phosphorylation levels of EGFR, STAT3 and CAMKII proteins. The mechanisms of action were associated with increased phosphorylation levels of c-Myc (T58) and instability of c-Myc proteins. DHA inhibited cell survival through an increased GSSG/GSH ratio and oxidative stress level in HPAF-II cells. DHA induced cell apoptosis through increased expression of Bax, c-caspase 3 and c-PARP proteins in HPAF-II cells. Moreover, treatment of DHA significantly inhibited nucleotide synthesis. In conclusion, DHA might significantly suppress the proliferation of PDAC cells and therefore have potential as an anti-cancer therapeutic agent.

Aims and objectives: To compare the frequency of nurse‐provided spiritual care across diverse cultures. Background: Given an ethical imperative to respect patient spirituality and religiosity, nurses are increasingly taught and expected to provide spiritual care. Although nurses report positive attitudes toward spiritual care, they typically self‐report providing it infrequently. Evidence about the reported frequency of spiritual care is constrained by substantial variation in its measurement. Design: This cross‐sectional, descriptive study involved secondary analysis of data collected in multiple sites globally using one quantitative instrument. Methods: Data were collected from practicing nurses using the Nurse Spiritual Care Therapeutics Scale and analysed using descriptive statistics and a meta‐analysis procedure with random‐effect modelling. Datasets from 16 studies completed in Indonesia, Iran, Malaysia, Philippines, Portugal, Taiwan, Turkey and the United States contributed to a pooled sample (n = 4062). STROBE guidelines for cross‐sectional observational studies were observed. Results: Spiritual care varied between countries and within countries. It was slightly more frequent within Islamic cultures compared with predominantly Christian cultures. Likewise, frequency of spiritual care differed between nurses in palliative care, predominantly hospital/inpatient settings, and skilled nursing homes. Overall, "Remaining present..." was the most frequent therapeutic, whereas documenting spiritual care and making arrangements for the patient's clergy or a chaplain to visit were among the most infrequent therapeutics. Conclusions: In widely varying degrees of frequency, nurses around the world provide care that is cognisant of the spiritual and religious responses to living with health challenges. Future research should be designed to adjust for the multiple factors that may contribute to nurses providing spiritual care. Relevance to clinical practice: Findings offer a benchmark and begin to inform nurse leaders about what may be normative in practice. They also encourage nurses providing direct patient care that they are not alone and inform educators about what instruction future nurses require. [ABSTRACT FROM AUTHOR]

For the optimal control problem of induction motor in field-weakening control, the paper introduced the optimal current distribution method of induction motor in field-weakening region. The result of Matlab/Simulink simulation verifies the optimal current distribution method has better effect of field-weakening control than traditional 1/ωr field-weakening method. The field-weakening control of the optimal current distribution method is realized under experiment platform based on TMS320LF2407A, which proves field-weakening control effect of the method is better than the traditional field-weakening method.

A mathematical model of induction motor was constructed. A new speed identification method of model reference adaptive system based on improved back-EMF was proposed on basis of analysis of stability of the model reference adaptive system based on reactive power. Error signal of speed identification of model reference adaptive system was re-constructed by the method. The error signal was composed of cross and dot product of the back-EMF error vector and the rotor flux vector. The rotor speed of the motor was identified by the error signal. The experimental results show that the new method is effective to solve problem of instability of the model referencing adaptive system under status of motor parking brake and power generation.

In this paper, the two state M-integral is extended from macrofacture to nanodefect mechanics. The question as to why the M-integral for a nanovoid or a soft nano-inclusion might be negative is clarified. It is concluded that the surface tension plays a dominant role in evaluating the M-integral, whereas the surface Lame constants yield much less influence than the surface tension. Their influence on the M-integral for a nanovoid or a soft nano-inclusion could be neglected. [DOI: 10.1115/1.3176998] Keywords: The two state M-integral, Mode decomposition, Nano-inclusion, Surface tension, Surface Lame constants

This paper deals with the M-integral analysis for a nano-inclusion in plane elastic materials under uni-axial or bi-axial loadings. Based on previous works (Gurtin and Murdoch, 1975, 'A Continuum Theory of Elastic Material Surfaces,' Arch. Ration. Mech. Anal., 57, pp. 291-323; Mogilevskaya, et al., 2008, 'Multiple Interacting Circular Nano-Inhomogeneities With Surface/Interface Effects,' J. Mech. Phys. Solids, 56, pp. 2298-2327), the surface effect induced from the surface tension and the surface Lame constants is taken into account, and an analytical solution is obtained. Four kinds of inclusions including soft inclusion, hard inclusion, void, and rigid inclusions are considered. The variable tendencies of the M-integral for each of four nano-inclusions against the loading or against the inclusion radius are plotted and discussed in detail. It is found that in nanoscale the surface parameters for the hard inclusion or rigid inclusion have a little or little influence on the M-integral, and the values of the M-integral are always negative as they would be in macroscale, whereas the surface parameters for the soft inclusion or void yield significant influence on the M-integral and the values of the M-integral could be either positive or negative depending on the loading levels and the surface parameters. Of great interest is that there is a neutral loading point for the soft inclusion or void, at which the M-integral transforms from a negative value to a positive value, and that the bi-axial loading yields similar variable tendencies of the M-integral as those under the uni-axial tension loading. Moreover, the bi-axial tension loading increases the neutral loading point, whereas the bi-axial tension-compression loading decreases it. Particularly, the magnitude of the negative M-integral representing the energy absorbing of the soft inclusion or void increases very sharply as the radius of the soft inclusion or void decreases from 5 nm to 1 nm. [DOI: 10.1115/1.3176997] Keywords: M-integral, nano-inclusion, Gurtin and Murdoch model, surface tension, surface Lame constants