Interactive computer programs for education and research: A survey

In this paper, a survey is given of the development and use of interactive computer packages for education and research in the field of control engineering, signal analysis and parameter estimation. Relevant aspects are: aims and goals of the package, its design and structure, the interaction, the development of the software, the necessary hardware, the educational aspects, the contents of the package and possible future developments.     

The Minor Structural Difference between the Antioxidants Quercetin and 4′O-Methylquercetin Has a Major Impact on Their Selective Thiol Toxicity

Antioxidants act as intermediates by picking up the high unselective reactivity of radicals and transferring it to other molecules. In this process the reactivity is reduced and becomes selective. This channeling of the reactivity can cause selective toxicity. The antioxidant quercetin is known to channel the reactivity towards thiol groups. The present study compares the thiol reactivity of quercetin with that of 4′O-methylquercetin (tamarixetin) towards creatine kinase (CK), a vital protein that contains a critical thiol moiety. Our results showed that oxidized quercetin and oxidized tamarixetin both adduct CK, which then loses its enzymatic function. Ascorbate, an important representative of the antioxidant network, is able to prevent adduction to and thus the inhibition of the enzyme by tamarixetin but not by quercetin. Apparently, tamarixetin is less thiol toxic than quercetin, because—rather than adduction to CK—tamarixetin quinone prefers to pass reactivity to the antioxidant network, i.e., to ascorbate. The findings exemplify that radical scavenging flavonoids pick up the reactivity of radicals and act as a pivot in directing the way the reactivity is channeled. A mere minor structural difference of only one methyl moiety between quercetin and tamarixetin appears to have a high impact on the selective, thiol toxicity.     

Fear and loathing in VR: the emotional and physiological effects of immersive games

Virtual Reality - Compared to traditional screen-based media, virtual reality (VR) generally leads to stronger feelings of presence. The current study aimed to investigate whether playing games in...     

Single Crystal Growth and Effect of Doping on Structural, Transport and Magnetic Properties of A1?xKxFe2As2 (A = Ba, Sr)

We demonstrate the preparation of large, free-standing iron pnictide single crystals with a size up to 20×10×1 mm³ using solvents in zirconia crucibles under argon atmosphere. Transport and magnetic properties have been investigated to study the effect of potassium doping on the structural and superconducting property of the compounds. The spin density wave (SDW) anomaly at T _s ∼138 K in BaFe₂As₂ single crystals from self-flux shifts to T _s ∼85 K due to Sn solvent growth. We show evidence for an incorporation of Sn on the Fe site. The electrical resistivity data show a sharp superconducting transition temperature T _c ∼38.5 K for a single crystal of Ba_0.68K_0.32Fe₂As₂. A nearly 100% shielding fraction and the bulk nature of the superconductivity for the single crystal are confirmed by magnetic susceptibility data. A sharp transition T _c ∼25 K occurs for the single crystal of Sr_0.85K_0.15Fe₂As₂. There is direct evidence for a coexistence of the SDW and superconductivity in the low doping regime of Sr_1−x K _x Fe₂As₂ single crystals. Structural implications of the doping effects as well as the coexistence of the two order parameters are discussed.     

Laparoscopic ventral hernia repair: a community hospital experience

OBJECTIVE: To study the suitable age for intraocular lens (IOL) implantation in children. METHODS: 240 (240 eyes) normal children aged 3-13 years old were selected. Their corneal refraction, anterior chamber depth, lens thickness and ocular axial length were measured with Roden-Stock Keratometer C-MES and Eyescan Model 55 separately. RESULTS: The corneal refraction of 3-year-old children, the anterior chamber depth and lens thickness after 5 years old, and the ocular axial length after 9 years old approach the adult magnitude. CONCLUSIONS: A 3-year-old child has been qualified with IOL implantation, the child younger than 9 years old should be implanted with a normal adult IOL and then corrected with glasses, and a child after 10 years old should be directly implanted with a proper dioptric IOL.     

Two genes in the rat homologous to human NKG2

OBJECTIVES: The purpose of this study was to investigate the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) genotype and endothelial cell dysfunction or hypercoagulable state in elderly hypertensive patients. BACKGROUND: Angiotensin-converting enzyme (ACE) insertion/ deletion (I/D) polymorphism was recently reported to be associated with various cardiovascular diseases. However, the precise mechanism of this association remains unknown, and some confounding factors might also affect the association. Endothelial cell dysfunction and coagulation activation play important roles in both the atherosclerotic process and the onset of cardiovascular events. METHODS: We identified the ACE I/D genotype and measured the plasma levels of markers of endothelial cell damage (von Willebrand factor [vWF] and thrombomodulin) and of coagulation activation (prothrombin fragment F1 + 2 [F1 + 2]) in 318 asymptomatic elderly patients with hypertension, aged 59-93 years. RESULTS: The vWF level was significantly higher in those with the DD genotype (n = 54) than in those with the II genotype (n = 131, p < 0.0001) or with the ID genotype (n = 133, p < 0.0001). The TM levels were also higher in patients with the ID genotype (p < 0.005) and the DD genotype (p < 0.01) than in those with the II genotype. There were no differences in F1 + 2 level among the groups. Positive correlations of systolic blood pressure with levels of both vWF and thrombomodulin were found predominantly in patients with the II genotype (both p < 0.001), but no correlation was noted in those with the DD genotype. CONCLUSIONS: Considering the increased plasma levels of both endothelial cell-derived markers in the hypertensive patients with ACE DD genotype, we speculate that the ACE D allele is a risk factor for the development of hypertensive cardiovascular disease associated with endothelial cell damage.     

Pancreatitis associated with diclofenac

A 34 year old female developed acute pancreatitis after commencing diclofenac for a painful arthropathy. The possible role of prostaglandin inhibition in non-steroidal analgesic drug-induced pancreatitis is discussed and the suggestion is made that serum amylase should be measured in patients who develop abdominal pain, following ingestion of non-steroidal anti-inflammatory