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Measuring the Frequency Response Functions (FRF) at the tool-tip is essential for the identification of chatter-free machining conditions. The tool-tip FRF in CNC machines are usually measured by impulse hammer tests in idle conditions, and the measured FRF remain relatively unchanged under operational conditions. This method is not effective in robotic machining, because the robot's vibration response in idle and operational conditions are significantly different. The robot's vibration response is pose-dependent and nonlinear and therefore strongly dependent on the operational conditions. This paper presents new methods for measuring the TCP (tool-tip) FRF of machining robots under operational conditions. In-process FRF are measured by leveraging the milling forces as the excitation source, and two approaches are proposed to achieve broadband, uncorrelated, and sufficiently exciting forces: i) milling of porous materials to generate randomized cutting forces, and ii) milling of a homogeneous material with spindle speed sweep. In the latter approach, the periodic content of cutting forces is used for excitation while in the former approach excitation by the random content is considered. A table dynamometer is used to measure the excitation (milling) forces and accelerometers are used to measure the resulting vibrations. The measured in-process FRF are then used to develop the chatter stability lobes diagram of the process, which determine the chatter-free combinations of the cutting depth and spindle speed for milling. Chatter experiments are conducted to confirm that the stability diagrams are more accurate when the presented in-process FRF measurements are used instead of the FRF measured in idle conditions. [ABSTRACT FROM AUTHOR]

This study aimed to explain the farmers' pro-environmental behaviors toward plant, soil and water conservation by adapting the value–belief–norm theory. This cross-sectional survey investigated 342 farmers in Mazandaran province, Iran. Data collection was done using a structured questionnaire and analyzed through structural equation modeling. The findings of the study confirmed the causal paths of variables in the value–belief–norm theory. As expected, in a causal chain, values influenced beliefs, and beliefs influenced norms, and finally norms influenced the plant, soil and water conservation behaviors among farmers. The results indicated that personal norms explained 60%, 10% and 5% of the variance of plant, soil and water conservation behavior variables, respectively. Also, ascription of responsibility explained 82% of the personal norms variance and awareness of consequences explained 35% of the variance of ascription of responsibility. In the following, ecological worldview (New Ecological Paradigm) explained 33% of the awareness of consequences' variance, and altruistic and egocentric values explained 72% of the New Ecological Paradigm' variance. In addition to providing support for the application of the value–belief–norm theory within the context of Iranian farmers, this study increased the understanding of the factors influencing the environmentally friendly behavior of farmers, helping agricultural policy makers and decision makers to formulate their policies for sustainable agricultural development with a better understanding of farmers' decisions and behaviors. [ABSTRACT FROM AUTHOR]

Objective: Bioactive glass and hydroxyapatite are biocompatible materials used as an adjunct to various dental materials. The present study aimed to evaluate the occlusion effects of bioactive glasses and hydroxyapatite on dental tubules. Materials and methods: We searched the PubMed/Medline, Embase, and Web of Science databases for the relevant records. The methodological quality of the studies was assessed by an accepted quality assessment tool. Results: From the electronic databases, 372 articles were retrieved. After evaluating the records, 35 in vitro studies were included. The studies revealed a low risk of bias. The primary outcomes from bioactive glass studies demonstrated the potential efficacy of both bioactive glass and hydroxyapatite in dentin tubule occlusion compared to the control. Conclusion: The current systematic review showed that bioactive glass and hydroxyapatite could effectively occlude the dentinal tubules. Thus, desensitizing agents containing bioactive glass and hydroxyapatite can be used to manage dentin hypersensitivity (DH). However, long-term follow-up clinical trials are required in the future before definitive recommendations can be made. Clinical relevance: This work achieved a satisfactorily systematic review for assessing desensitizing agents containing bioactive glass and hydroxyapatite in dentine hypersensitivity treatments recommended for clinical practice and research. [ABSTRACT FROM AUTHOR]

Background: PIN1, a peptidyl-prolyl cis–trans isomerase, specifically can regulate phosphorylation of proteins on serine/threonine residues that precede proline and has critical roles in cell proliferation and transformation. Many studies have revealed that overexpression of PIN1 is involved in the malignant biological behavior of various cancers, but to date, no meta-analyses have evaluated PIN1 clinical and prognostic value in patients with malignant tumors. Methods: We retrieved related articles from PubMed, Web of Science and Scopus databases up to April 20, 2019. Pooled odds ratios (ORs) and hazard ratios (HRs) with 95% CIs were used to estimate the correlation of PIN1 expression with clinicopathological characteristics and survival outcomes. The methodology was according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and the Cochrane Collaboration guidelines. Results: A total of 20 studies containing 2574 patients with various tumors were included in this analysis. Pooled results showed that PIN1 overexpression was significantly associated with the advanced clinical stages of cancer (OR = 1.37, 95% CI 1.06–1.78), positive lymph node metastasis (OR = 1.65, 95% CI 1.15–2.37) and poor prognosis (HR = 2.40, 95% CI 1.55–3.74), although no correlation with poor differentiation was found. Conclusions: These results suggest that high expression of PIN1 can be considered as a risk factor for progression and invasion of malignant tumors and thus may serve as a promising therapeutic target and prognostic biomarker for human solid tumors. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the preclinical utility and antitumor efficacy of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) delivered by Ad-IU2, a prostate-specific replication-competent adenovirus (PSRCA), against androgen-independent prostate cancer. Through transcriptional control of adenoviral early genes E1a, E1b and E4, as well as TRAIL by two bidirectional prostate-specific enhancing sequences (PSES), the expression of TRAIL and adenoviral replication was limited to prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA)-positive cells. Ad-IU2 induced fivefold greater apoptosis selectively in PSA/PSMA-positive CWR22rv and C4-2 cells than an oncolytic adenoviral control. Furthermore, prolonged infection with Ad-IU2 reversed TRAIL resistance in LNCaP cells. Ad-IU2 showed superior killing efficiency in PSA/PSMA-positive prostate cancer cells at doses five- to eight-fold lower than required by a PSRCA to produce a similar effect; however, this cytotoxic effect was not observed in non-prostatic cells. As an enhancement of its therapeutic efficacy, Ad-IU2 exerted a TRAIL-mediated bystander effect through direct cell-to-cell contact and soluble factors such as apoptotic bodies. In vivo, Ad-IU2 markedly suppressed the growth of subcutaneous androgen-independent CWR22rv xenografts compared with a PSRCA at 6 weeks after treatment (3.1- vs 17.1-fold growth of tumor). This study shows the potential clinical utility of a PSRCA armed with an apoptosis-inducing ligand. [ABSTRACT FROM AUTHOR]

Enzyme pro-drug suicide gene therapy has been hindered by inefficient viral delivery and gene transduction. To further explore the potential of this approach, we have developed AdIU1, a prostate-restricted replicative adenovirus (PRRA) armed with the herpes simplex virus thymidine kinase (HSV-TK). In our previous Ad-OC-TK/ACV phase I clinical trial, we demonstrated safety and proof of principle with a tissue-specific promoter-based TK/pro-drug therapy using a replication-defective adenovirus for the treatment of prostate cancer metastases. In this study, we aimed to inhibit the growth of androgen-independent (AI), PSA/PSMA-positive prostate cancer cells by AdIU1. In vitro the viability of an AI- PSA/PSMA-expressing prostate cancer cell line, CWR22rv, was significantly inhibited by treatment with AdIU1 plus GCV (10 μg ml−1), compared with AdIU1 treatment alone and also cytotoxicity was observed following treatment with AdIU1 plus GCV only in PSA/PSMA-positive CWR22rv and C4-2 cells, but not in the PSA/PSMA-negative cell line, DU-145. In vivo assessment of AdIU1 plus GCV treatment revealed a stronger therapeutic effect against CWR22rv tumors in nude mice than treatment with AdIU1 alone, AdE4PSESE1a alone or in combination with GCV. Our results demonstrate the therapeutic potential of specific-oncolysis and suicide gene therapy for AI-PSA/PSMA-positive prostate cancer gene therapy.Cancer Gene Therapy (2009) 16, 73–82; doi:10.1038/cgt.2008.59; published online 5 September 2008 [ABSTRACT FROM AUTHOR]

This paper reports investigation conducted to study the fatigue performance of steel fibre reinforced concrete (SFRC) containing fibres of mixed aspect ratio. An extensive experimental program was conducted in which 90 flexural fatigue tests were carried out at different stress levels on size 500 mm × 100 mm × 100 mm SFRC specimens respectively containing 1.0%, 1.5% and 2.0% volume fraction of fibres. About 36 static flexural tests were also conducted to determine the static flexural strength prior to fatigue testing. Each volume fraction of fibres incorporated corrugated mixed steel fibres of size 0.6 mm × 2.0 mm × 25 mm and 0.6 mm × 2.0 mm × 50 mm in ratio 50:50 by weight. The results are presented both as S-N relationships, with the maximum fatigue stress expressed as a percentage of the strength under static loading, and as relationships between actually applied fatigue stress and number of loading cycles to failure. Two-million-cycle fatigue strengths of SFRC containing different volume fractions of mixed fibres were obtained and compared with plain concrete. [ABSTRACT FROM AUTHOR]