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Automatic assembly equipment is the key to improving the efficiency and quality of workpiece assembly. The precision of assembly directly influences the overall quality of the assembled product. To optimise the position control accuracy in the automatic assembly equipment, a variable universe fuzzy proportional integral (VUFPI) controller optimised by the sparrow search algorithm (SSA) is developed in this paper. The developed controller adopts the SSA to adjust in real time the universe of the fuzzy controller according to the deviation of the servo system. The servo system model is established to evaluate the performance of the proposed SSAVUFPI controller; furthermore, the SSA-VUFPI controller is implemented in the automatic assembly equipment for experimental evaluation. The analysis results demonstrate that the proposed SSA-VUFPI controller is capable of improving the anti-interference ability and position accuracy of the servo system compared to traditional PI, VUFPI, and currently used back propagation neural network proportional-integralderivative (BP-PID), fractional-order PID (FOPID), and SSAPID controllers. Moreover, it effectively improves the position accuracy of the workpiece and ultimately improves the quality of the assembly. [ABSTRACT FROM AUTHOR]

Automatic assembly equipment is the key to improving the efficiency and quality of workpiece assembly. The precision of assembly directly influences the overall quality of the assembled product. To optimise the position control accuracy in the automatic assembly equipment, a variable universe fuzzy proportional integral (VUFPI) controller optimised by the sparrow search algorithm (SSA) is developed in this paper. The developed controller adopts the SSA to adjust in real time the universe of the fuzzy controller according to the deviation of the servo system. The servo system model is established to evaluate the performance of the proposed SSAVUFPI controller; furthermore, the SSA-VUFPI controller is implemented in the automatic assembly equipment for experimental evaluation. The analysis results demonstrate that the proposed SSA-VUFPI controller is capable of improving the anti-interference ability and position accuracy of the servo system compared to traditional PI, VUFPI, and currently used back propagation neural network proportional-integralderivative (BP-PID), fractional-order PID (FOPID), and SSAPID controllers. Moreover, it effectively improves the position accuracy of the workpiece and ultimately improves the quality of the assembly. [ABSTRACT FROM AUTHOR]

The objective of this work is to evaluate the influences of electroneutral quaternization and sulfosuccination (electroneutral QS) on the adhesion of starch to viscose fibres and sizing properties of starch to viscose yarns at low temperature in order to study if the derivatization can improve the serviceability of starch applied for sizing viscose yarns at low temperature. The quaternized and sulfosuccinylated starch (QSS) with electroneutrality has been synthesized in aqueous dispersion by a quaternization of hydrolyzed cornstarch (HS) with N-(3-chloro-2-hydroxypropyl) trimethylammonium chloride and a further sulfosuccination is done for introducing a fixed mole ratio of 3-(trimethylammonium chloride)-2- hydroxypropyl (TACHP) substituents to sulfosuccinate (SS) substituents onto starch chains. It is found that electroneutral QS is available to ameliorate the adhesion at different temperatures. The amelioration in the adhesion depends on the level of the modification. In addition, the modification improves the mechanical properties of the sized viscose yarns, and decreases hairiness of sized yarns, even if the temperature of the electroneutral QSS paste is lowered to 60 °C. Electroneutral QSS with a degree of substitution of 0.0438 is expected to show a potential application in sizing viscose yarns at 60 °C. [ABSTRACT FROM AUTHOR]

A hydrophilic fibrous membrane consisting of a network of a non-crystalline hydrophobic polymer and an in situ crosslinked hydrophilic chitosan polymer is studied. This chitosan-functionalized membrane can be employed as a support for immobilization of horseradish peroxidases (HRPs). The immobilized HRPs (mass loading ~110 mg/g) show high stabilities over a wide pH range of 4~10 and temperature range of 25~60oC. In addition, the immobilized HRPs can function as a recyclable biocatalyst for catalytic oxidation of p-nitrophenol (PNP). After 10 cycles, the PNP removal efficiency is 70 percent. The results demonstrate that the chitosan-functionalized fibrous membrane is a promising support for immobilization of enzymes and has applications related to enzyme catalysis. [ABSTRACT FROM AUTHOR]

Background: Posttranslational histone modifications (PTHMs) are altered by arsenic, an environmental carcinogen. PTHMs are also influenced by nutritional methyl donors involved in one-carbon metabolism (OCM), which may protect against epigenetic dysregulation. Methods: We measured global levels of three PTHMs, which are dysregulated in cancers (H3K36me2, H3K36me3, H3K79me2), in peripheral blood mononuclear cells (PBMC) from 324 participants enrolled in the Folic Acid and Creatine Trial, a randomized trial in arsenic-exposed Bangladeshi adults. Sex-specific associations between several blood OCM indices (folate, vitamin B12, choline, betaine, homocysteine) and PTHMs were examined at baseline using regression models, adjusted for multiple tests by controlling for the false discovery rate (PFDR). We also evaluated the effects of folic acid supplementation (400 μg/d for 12 weeks), compared with placebo, on PTHMs. Results: Associations between choline and H3K36me2 and between vitamin B12 and H3K79me2 differed significantly by sex (Pdiff < 0.01 and <0.05, respectively). Among men, plasma choline was positively associated with H3K36me2 (PFDR < 0.05), and among women, plasma vitamin B12 was positively associated with H3K79me2 (PFDR < 0.01). Folic acid supplementation did not alter any of the PTHMs examined (PFDR = 0.80). Conclusions: OCM indices may influence PTHMs in a sex-dependent manner, and folic acid supplementation, at this dose and duration, does not alter PTHMs in PBMCs. Impact: This is the first study to examine the influences of OCM indices on PTHMs in a population that may have increased susceptibility to cancer development due to widespread exposure to arsenic-contaminated drinking water and a high prevalence of hyperhomocysteinemia. [ABSTRACT FROM AUTHOR]

Background: The utility of functional deficits in patients with mild cognitive impairment is not established.Materials and Methods: In 3886 individuals with mild cognitive impairment evaluated and followed at 34 National Alzheimer Coordinating Center sites, informant-reported Pfeffer Functional Activities Questionnaire (FAQ) items associated with progression to dementia were derived in a training set (n=1943) and tested in the validation set (n=1943).Results: In the training set, the optimal combination comprised 6 FAQ items (FAQ6): difficulties with finances (2 items), remembering events/appointments, playing games of skill, current events, and travel. In the validation set, hazard ratio for dementia increased from 2.00 for 1 FAQ6 deficit to 5.56 for 6 FAQ6 deficits. In patients 50 to 67 years old with high Mini Mental State Exam scores, dementia risk rose from 12.06% for no FAQ6 deficits to 56.75% for 6 functional deficits. Likelihood of progression to dementia reached 80% to 89% in older age groups with low Mini Mental State Exam and severe FAQ6 deficits.Conclusions: Specific functional deficits increased dementia risk and, with age and global cognition, constituted a validated clinical algorithm to estimate dementia risk. Clinicians can use this clinically important algorithm to personalize decision-making about further investigation and identify high-risk patients for early treatment or inclusion in clinical trials. [ABSTRACT FROM AUTHOR]

Background: Depletion of global 5-hydroxymethylcytosine (5- hmC) is observed in human cancers and is strongly implicated in skin cancer development. Although arsenic (As)-a class I human carcinogen linked to skin lesion and cancer risk-is known to be associated with changes in global %5-methylcytosine (%5-mC), its influence on 5-hmC has not been widely studied. Methods: We evaluated associations of As in drinking water, urine, and blood with global %5-mC and %5-hmC in two studies of Bangladeshi adults: (i) leukocyte DNA in the Nutritional Influences on Arsenic Toxicity study (η = 196; 49% male, 19-66 years); and (ii) peripheral blood mononuclear cell DNA in the Folate and Oxidative Stress study (η = 375; 49% male, 30-63 years). Results: Overall, As was not associated with global %5-mC or %5-hmC. Sex-specific analyses showed that associations of As exposure with global %5-hmC were positive in males and negative in females (P for interaction < 0.01). Analyses examining interactions by elevated plasma total homocysteine (tHcys), an indicator of B-vitamin deficiency, found that tHcys also modified the association between As and global %5-hmC (P for interaction < 0.10). Conclusion: In two samples, we observed associations between As exposure and global %5-hmC in blood DNA that were modified by sex and tHcys. Impact: Our findings suggest that As induces sex-specific changes in 5-hmC, an epigenetic mark that has been associated with cancer. Future research should explore whether altered %5-hmC is a mechanism underlying the sex-specific influences of As on skin lesion and cancer outcomes. [ABSTRACT FROM AUTHOR]

In order to evaluate the effect of polyphosphonic acid used as a stabilizer on the hydrogen peroxide, VSP2 (Vent Sizing Package 2) was employed to carry out the thermal runaway reaction for the various concentrations of Amino Trimethylene Phosphonic Acid(ATMP) with hydrogen peroxide (H 2 O 2 ) and H 2 O 2 mixes with 100 ppm Fe 3+ , respectively. Thermodynamic parameters were recorded under the adiabatic condition, and the time to the maximum rate TMRad at 25 °C was obtained from the dynamics data. The results indicated that polyphosphonic acid could restrain the effect of temperature and Fe 3+ on the catalytic decomposition of H 2 O 2 , and reduced the risk of thermal runaway significantly. The initial decomposition temperature T 0 of H 2 O 2 rises as the concentration of ATMP increases but stops rising when the concentration exceeds 400 ppm. In the environment of 400 ppm ATMP, it was discovered that T 0 of H 2 O 2 increased from 50°C to 115°C. [ABSTRACT FROM AUTHOR]

In order to evaluate the effect of polyphosphonic acid used as a stabilizer on the hydrogen peroxide, VSP2 (Vent Sizing Package 2) was employed to carry out the thermal runaway reaction for the various concentrations of Amino Trimethylene Phosphonic Acid(ATMP) with hydrogen peroxide (H 2 O 2 ) and H 2 O 2 mixes with 100 ppm Fe 3+ , respectively. Thermodynamic parameters were recorded under the adiabatic condition, and the time to the maximum rate TMRad at 25 °C was obtained from the dynamics data. The results indicated that polyphosphonic acid could restrain the effect of temperature and Fe 3+ on the catalytic decomposition of H 2 O 2 , and reduced the risk of thermal runaway significantly. The initial decomposition temperature T 0 of H 2 O 2 rises as the concentration of ATMP increases but stops rising when the concentration exceeds 400 ppm. In the environment of 400 ppm ATMP, it was discovered that T 0 of H 2 O 2 increased from 50°C to 115°C. [ABSTRACT FROM AUTHOR]

The article presents an analysis of data from the Nordic Research on Ageing (NORA) study aimed at probing the effect of the presence of frailty features on mortality in 75-year-old men and women with varying degrees of depressive symptomatology. Findings discussed include the link between depressive symptoms, characteristics of frailty and mortality, the possible models explaining the depressed-frail phenotype, and the higher risk of death from depressive illness and conditions of frailty.

The article discusses the study that determined the relationship between diagnostic delay or lag time of unilateral and bilateral retinoblastoma, and sociodemographic factors on the extent of disease at diagnosis. Findings discussed include lag time to predict bilateral disease stage at diagnosis using Saint Jude's, and International Staging System (ISS) criteria, and overall survival (OS), and lag time to not predict extent of disease, nor OS in unilateral retinoblastoma disease.

The article discusses research in geriatric psychiatry, with a focus on an investigation of the effects of cognitive performance and depression on functional impairment in older people with mild cognitive impairment (MCI). Topics include measurement of memory impairment and cognitive processing speed, executive functioning and dysfunction, and depressive symptoms.

The article examines the association of exposure to arsenic to global posttranslational histone modifications in vitro among participants in a clinical trial in Bangladesh. Water and urinary arsenic concentrations including global levels of histone 3 lysine 9 di-methylation were measured. Arsenic and other posttranslational histone modifications differed in a gender-dependent manner. Arsenic exposure is suggested to link to epigenetic dysregulation.

The article discusses a research study which documented the association of urinary naphthol metabolites with chromosomal aberrations, including translocations, in five-year old urban minority children. The sturdy examined the link between chromosomal aberrations and concurrent concentrations of polycyclic aromatic hydrocarbon (PAH) metabolites measured in urine. The researchers recorded the levels of occurrence and frequency of chromosomal aberrations in lymphocytes.

The article discusses the virtual reality that could benefit virtual process engineering (VPE) in combination with computer simulations with real-time online data for engineers. It notes that engineers through the VPE could be able to simulate industrial process with high accuracy and compare simulation outputs with experimental results. It also explores the use of advanced computational science in chemical engineering, use of computer modeling and the acceleration of process and technologies.

Abstract: In order to realize information sharing and information reuse of technique preparation process, idea of domain ontology was applied in technique preparation process. The concept of technique preparation domain ontology was proposed and its structure was designed. Moreover, the information retrieval framework for technique preparation based on domain ontology was put forward and the flowchart of the proposed approach was designed. Furthermore, the similarity relation between concepts was elaborated and the similarity computing approach of domain ontology was designed to resolve the problem of technique preparation information similarity. Finally, an application case was illustrated and the information retrieval approach was proved efficient. [Copyright &y& Elsevier]

Objective: To examine the utility of single-photon emission computed tomography (SPECT) to predict conversion from mild cognitive impairment (MCI) to Alzheimer disease (AD). Design: Longitudinal, prospective study. Setting: University-based memory disorders clinic. Participants: One hundred twenty seven patients with MCI and 59 healthy comparison subjects followed up for 1-9 years. Measurements: Diagnostic evaluation, neuropsychological tests, social/cognitive function, olfactory identification, apolipoprotein E genotype, magnetic resonance imaging, and brain 99mTc hexamethyl-propylene-aminoxime SPECT scan with visual ratings, and region of interest (ROI) analyses were done. Results: Visual ratings of SPECT temporal and parietal blood flow did not distinguish eventual MCI converters to AD (TV = 3D from nonconverters (TV = 96), but the global rating predicted conversion (41.9% sensitivity and 82.3% specificity, Fisher's exact test p = 0.013). Blood flow in each ROI was not predictive, but when dichotomized at the median value of the patients with MCI, low flow increased the hazard of conversion to AD for parietal (hazard ratio: 2.96, 95% confidence interval: 1.16-7.53, p = 0.023) and medial temporal regions (hazard ratio: 3-12, 95% confidence interval: 1.14-8.56, p = 0.027). In the 3-year follow-up sample, low parietal (p <0.05) and medial temporal (p <0.01) flow predicted conversion to AD, with or without controlling for age, Mini-Mental State Examination, and apolipoprotein E ∈4 genotype. These measures lost significance when other strong predictors were included in logistic regression analyses: verbal memory, social/cognitive functioning, olfactory identification deficits, hippocampal, and entorhinal cortex volumes. Conclusions: SPECT visual ratings showed limited utility in predicting MCI conversion to AD. The modest predictive utility of quantified low parietal and medial temporal flow using SPECT may decrease when other stronger predictors are available. [ABSTRACT FROM AUTHOR]