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INTRODUCTIONIt is unclear whether polygenic risk for neurodegenerative disease is associated with cognitive performance and physical health.METHODSThis study tested whether polygenic scores for Alzheimer’s disease (AD), Amyotrophic Lateral Sclerosis (ALS), or frontotemporal dementia (FTD) are associated with cognitive performance and physical health. Group-based analyses were performed to compare associations with cognitive and physical function outcomes in the top and bottom 10% for the three neurodegenerative polygenic risk scores.RESULTSHigher polygenic risk scores for AD, ALS, and FTD were associated with lower cognitive performance. Higher polygenic risk scores for FTD was also associated with increased forced expiratory volume in 1s and peak expiratory flow. A significant group difference was observed on the symbol digit substitution task between individuals with high polygenic risk for FTD and high polygenic risk for ALS.DISCUSSIONOur results suggest overlap between polygenic risk for neurodegenerative disorders, cognitive function and physical health.

Background Sequential human herpes virus (HHV) reactivation is well known in drug reaction with eosinophilia and systemic symptom (DRESS), but such a phenomenon has seldom studied in other types of cutaneous adverse drug reactions (cADRs). Moreover, the association between viral reactivations and cytokine or chemokine changes is largely unknown. We aimed to evaluate the viral reactivation rates of HHV-6, HHV-7, Epstein–Barr virus (EBV), and cytomegalovirus (CMV) in different cADRs and their impacts on clinical prognosis. Cytokine and chemokine changes with viral reactivations were also examined. Methods A prospective study was conducted to monitor the viral statuses of patients with different cADRs by polymerase chain reaction and serum-specific antibody titers. Changes in plasma cytokine and chemokine levels were also evaluated by sequential blood samples. Results Among the various cADRs, HHV-6 reactivation was only observed in DRESS, but EBV and CMV could be detected in other cADRs. Many proinflammatory cytokines and chemokines, including interleukin (IL)-1β, IL-2, IL-6, interferon-γ, tumor necrosis factor-α, were significantly lower in DRESS patients with HHV-6 reactivation when compared to those without HHV-6 reactivation. In addition, these mediators were significantly lower before and during HHV-6 reactivation, compared to cytokine levels after HHV-6 reactivation in the same patient. Conclusion HHV-6 reactivation was only observed in DRESS patients, not in any other cADR. In DRESS patients, some proinflammatory cytokines were significantly lower before or during HHV-6 reactivation.

A common problem encountered in gas-assisted injection molding (GAIM) is “gas fingering,” i.e., gas bubbles penetrating outside designed gas channels and forming finger-shaped branches. Severe gas fingering can result in significant reductions in part stiffness. In this paper, nondestructive techniques have been used to quantitatively characterize gas bubble geometry in specially designed GAIM parts. Based on the quantitative measurements, the most crucial process parameters to control gas fingering have been identified through factorial design experiments. More detailed process studies reveal that there is an intrinsic relationship between gas fingering and cross-sectional gas bubble shape. By examining the effects of gas channel design and material type on the gas bubble shape, some useful gas channel design guidelines have been obtained.

Films of electroactive polymers, such as polyaniline (PAN) in its emeraldine base form, and poly(3-alkylthiophene), poly(3-hexylthiophene) (P6TH), poly(3-octylthiophene) (P8TH), and poly(3-dodecylthiophene) (P12TH) can be readily functionalized via thermal or near ultraviolet-light-induced surface graft copolymerization with monomers of polyelectrolyte, polyampholyte and polymeric acids. The monomers used in the present work include dimethyl sulphate quaternized dimethylamino-ethylmethacrylate (DMAEM·C2H6SO4), 3-dimethyl(methacryloyloxyethyl)ammonium propane sulphonate (DMAPS), acrylic acid (AAc) and a sodium salt of styrene sulphonic acid (NaSS). The surface structures and compositions of the electroactive polymer films after functionalization via graft copolymerization were characterized by angle-resolved X-ray photoelectron spectroscopy. Graft copolymerization of poly(3-alkylthiophene) films, but not PAN films, with the hydrophilic monomers readily results in a stratified surface microstructure arising from the migration of the hydrophilic graft chains beneath a thin surface layer which is much richer in the substrate chains. On the other hand, graft copolymerization of PAN films with AAc and NaSS readily gives rise to a self-protonated (and thus conductive) surface structure.

Significant differences were observed in the amount and proportion of free amino acids in different organs of Arabidopsis thaliana (L.) Heynh, ecotype Columbia. The most notable were found for proline, which formed 17-26% of the total free amino acid concentration in reproductive tissues (floret and seed), but only 1-3% of the total free amino acid concentration in vegetative tissues (rosette leaf and root). Proline accumulation was associated with tissues that had relatively low water contents. Tissues which displayed high water contents, such as rosette leaves, contained low levels of proline. A significant increase in the levels of proline accumulation occurred in plants subjected to experimentally induced low water potentials as compared to unstressed plants. For instance, an 8-10-fold increase in proline was observed in the presence of 120 mmol kg -1 NaCl or KCl, and a 20-fold increase was stimulated by 60mmol kg -1 PEG. However, in addition to the accumulation of proline, massive accumulation of Na + , K + and Cl - ions occurred in tissues of plants stressed with salt. No significant differences were observed in mineral ions in plants stressed with PEG. Isotope tracer experiments with 14 C compounds established that glutamate, ornithine and arginine are precursors of the proline biosynthesis induced by PEG in response to low water potentials in Arabidopsis thaliana. We conclude that the accumulation of proline in response to PEG occurs through increased biosynthesis.

Herpesviruses may play roles in the development of periodontal diseases. This study analyzed the effects of herpes simplex virus type 1 (HSV-1) infection on neutrophil function. The effects of lipopolysaccharide (LPS) from the periodontal pathogen, Porphyromonas gingivalis, during HSV-1 infection were also determined.Purified HSV-1 was pretreated with buffer containing no serum, with HSV-1 immunoglobulin G (IgG)-positive serum (HSV-1 antiserum) or with control serum. Neutrophils were mock-infected or infected with the pretreated HSV-1. Viral binding and phagosome formation were detected using immunostaining. Intracellular reactive oxygen species (ROS) were determined using 2',7'-dichlorofluorescin diacetate and fluorometry. Leukotriene B(4) (LTB(4)) and interleukin-8 (IL-8) were detected using enzyme immunoassays. Release of matrix metalloproteinase-9 (MMP-9) was examined using gelatin zymography. Phosphorylation of Akt/glycogen synthase kinase-3 (GSK-3) was determined using western blotting.HSV-1 bound directly to neutrophils and enhanced the release of MMP-9. HSV-1 immune complexes, formed in the HSV-1 antiserum, bound neutrophils and induced the formation of early phagosome more effectively than did HSV-1 alone. The relative levels of ROS and phosphorylation of Akt/GSK-3 were increased significantly in neutrophils after infection with HSV-1 immune complexes. Infection with HSV-1 and HSV-1 immune complexes also stimulated the production of inflammatory mediators, LTB(4) and IL-8. Moreover, LPS enhanced the HSV-1-stimulatory production of IL-8.This study demonstrated differences in neutrophils infected with HSV-1 alone or with HSV-1 immune complexes, suggesting that opsonization of HSV-1 might enhance its effects on neutrophils. The in vitro findings suggest that HSV-1 infection may induce the inflammatory response and affect periodontal health.

This work employs a coupled analysis of the fluid flow and heat transfer in the polymer melt during the filling and post-filling stages of the injection-molding process and of mold cooling/heating which occurs during the entire process. Polymer melt analysis (PMA) has been carried out through a unified theoretical model implemented using a hybrid finite-element/finite-difference/control-volume numerical solution of the generalized Hele-Shaw flow of a compressible viscous fluid under non-isothermal conditions. Further, mold-cooling analysis (MCA) has been carried out utilizing a periodic heat conduction model implemented using a modified three-dimensional boundary-element method. To faithfully accommodate the effects of mold cooling on the fluid flow and heat transfer in the polymer melt, PMA and MCA have been coupled for appropriate data exchange and iterations carried out until a convergent solution for mold temperatures and for flow, pressure and temperatures within the polymer melt is obtained. The results obtained from this integrated simulation for different test cases have been compared with experimental data and a favorable agreement has been noticed. Using an illustrative example, the results are discussed in detail.

The advent of CAE (computer-aided engineering) technology for injection molding and related processes is having a rapidly growing impact on the molding industry. Proper use of this technology has enhanced engineers' capability in handling all aspects of the molding process and has been proven to benefit both productivity and product quality. However, while CAE can serve as a powerful tool to help engineers make rational engineering decisions, it is by no means a panacea for solving all molding problems. The viability of CAE packages depends heavily not only on the scientific principles and numerical methods used for developing the software, but also on the reliability of the input data such as material properties and process conditions. This article discusses the state-of-the-art of the technology with an emphasis on simulations of latest innovations in injection molding. A three-layer approach that systematically integrates and efficiently utilizes various CAE tools to solve design problems at different levels of sophistication is also presented. © 1993 by John Wiley & Sons, Inc.

Steady-shear-viscosity data sets for commercial-grade acrylonitrile-butadiene-styrene terpolymer, nylon, polycarbonate, poly(methylmethacrylate), and polystyrence are fitted in terms of a generalized Cross/Carreau modeling for the shear-rate dependence. Based upon extensive data sets from the open literature as well as in-house measurements, it is shown that the shear-rate dependence can be more accurately described in terms of the Cross rather than Carreau model. Although the resulting viscosity fits based upon these two models might differ by 20% or more for the same well-characterized data set, the resulting effect upon simulating the injection-molding process is found to be much smaller since such predictions reflect a range of shear stresses (varying linearly from centerline to wall of cavity) over which the two models alternate in relative magnitude. This is demonstrated by detailed representative numerical predictions which are presented for both the filling and post-filling stages.

This study employs a unified theoretical model to simulate the filling and postfilling stages of the injection-molding process. Implementation of such a model is based on a hybrid finite-element/finite-difference numerical solution of the generalized Hele-Shaw flow of a compressible viscous fluid under nonisothermal conditions. The shear viscosity of the polymeric material is represented by a Cross model for the shear-rate dependence and a WLF-type functional form for the temperature and pressure dependence, whereas the specific volume is modeled in terms of a double-domain Tait equation. The analysis also handles variable specific heat and thermal conductivity of the polymer as a function of temperature. Complex thin parts of variable thickness can be modeled and discretized by flat, triangular finite elements which may have arbitrary orientation in three-dimensional space, whereas runners and possible round pins or bosses in the part are represented as one-dimensional circular-tube elements. A control-volume scheme is employed that leads to automatic melt-front advancement during the cavity-filling stage.

The unified numerical simulation of the filling/postfilling stages of the injection-molding process described in Part I is compared in the present paper with experimental results obtained with instrumented test molds. Flush-mounted pressure traces in the delivery system as well as in the cavity are favorably compared with corresponding predictions for both an amorphous and a semicrystalline polymer. It is demonstrated that the present unified formulation is well suited to handle complicated molds where compressibility effects can become important even during the filling stage, as portions of the cavity fill and undergo a packing behavior even when other regions of the cavity are still only partially filled.

To assess warpage and shrinkage of an injection-molded plastic part, an integrated computer-aided engineering (CAE) system has been developed. This integrated system employs a simultaneous analysis of the compressible fluid flow, heat transfer, and residual stresses in the polymer during the filling and postfilling stages of the injection molding process and of mold cooling/heating that occurs throughout the entire process. Using the polymer temperature and pressure distributions as a function of time, an analysis has been performed to predict the residual stresses, treating the polymer as a viscoelastic material. The resultant loading is interfaced with the structural analysis program ABAQUSTM to predict the postmolding shape of the plastic part. Analysis has also been performed to evaluate the load-deflection behavior of a molded part and the effects of different degrees of material anisotropy.

A novel adaptive deconvolution and system identification scheme is introduced for a linear, non-minimum-phase finite-impulse-response (FIR) system driven by non-Gaussian white noise. The adaptive scheme is based on approximating the FIR system by noncausal autoregressive (AR) models and using higher order cumulants of the system output. As such, it is a blind equalization (deconvolution) scheme. The set of updated AR parameters is obtained by using a gradient-type algorithm and by using higher order cumulants instead of time samples of the output signal. It is demonstrated by means of extensive simulations that the adaptive scheme works well for both stationary and nonstationary cases. As expected, it outperforms the autocorrelation-based gradient method for nonminimum-phase system identification and deconvolution. Performance comparisons to existing methods are given, using as figures of merit the probability of errors in the restored input sequence, computational complexity, and convergence rate. >

In Taiwan, cervical cancer is the leading malignancy among women. For the early detection of cervical neoplasia, light-induced fluorescence spectroscopy was conducted ex vivo to assess the ability of this technique to differentiate cervical neoplastic tissue (20 samples) from normal or inflammatory cervical tissue (37 samples) at an excitation wavelength of 280 nm. The principal fluorescent peaks occurred within +/- 5 nm of 330 nm and 470 nm emission. At 330 nm emission, the spectrum of the normal or inflammatory tissue was significantly stronger than that of the neoplastic tissue after are normalization. However, at 470 nm emission, the spectrum of the normal or inflammatory tissue was significantly weaker than that of the neoplastic tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the 5 +/- nm peak area of each sample was calculated and paired. The ratios showed that histologically neoplastic lesions could be distinguished from inflammatory samples using a 280-nm-excitation wavelength with a sensitivity, specificity and positive predictive value of 94%, 82% and 73%, respectively. The average ratio of malignant or dysplastic cervical samples was significantly greater than that of the inflammatory samples (p0.001). Our ex vivo study indicated that light-induced fluorescence spectroscopy may be useful in differentiating malignant or premalignant from normal or inflammatory cervical tissue.

For the early detection of oral neoplasia, light-induced fluorescence spectroscopy was used to measure the fluorescence emission of malignant (squamous cell carcinomaverrucous carcinoma) and premalignant (epithelial dysplasia, hyperkeratosislichen planus) oral tissues as well as normal oral mucosa ex vivo to assess the ability of this technique to distinguish neoplastic from normal oral tissues. The emission spectra of histologically normal and neoplastic oral tissues were obtained under excitation wavelengths varied from 270 nm to 400 nm at 10-nm intervals. At 300-nm excitation, the most intensely fluorescent peak occurred at 330-nm and 470 nm emission. At 330-nm emission, the spectrum of the malignant oral tissue was significantly stronger than that of the normal oral mucosal tissue after area normalization. However, at 470-nm emission, the spectrum of the malignant oral tissue was significantly weaker than that of the normal oral mucosal tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the +/-5 nm peak area of each sample was calculated and paired. The histogram of ratios showed that histologically neoplastic oral tissues could be distinguished from normal oral mucosal tissues using the 300 nm excitation wavelength. The average ratio of malignant or premalignant oral samples was significantly greater than that of the normal oral mucosal samples (p0.001). This ex vivo study indicated that fluorescence spectroscopy may be useful in differentiating malignant or premalignant oral tissue from normal oral mucosa.

The most frequently discussed ethical issue on the subject of cancer is whether patients should be told their diagnosis. Cancer patients' knowledge of their diagnosis and the relationship between patient characteristics and that knowledge were evaluated in a cross-sectional study. From July 1992 to December 1993 at Tri-Service General Hospital, Taipei, a total of 964 patients with cytologically- or pathologically-proven cancer were studied. Of those studied, 359 patients (37.2%) knew their diagnosis. The proportion of patients who believed that they had a benign tumor was 25.1%; 12.6% believed they had nonneoplastic disease (inflammation or other chronic disease); 7.5% believed they had precancerous changes; and 17.6% knew nothing about their diagnosis. Multivariate analyses showed that patients with the following characteristics were inclined to know their diagnosis: younger age (20-59 yr), higher levels of education (9 yr) with relatives of a high socioeconomic status, cancer of a genital organ, cancer requiring disfiguring treatment (osteosarcoma, leukemia), cancer in obvious sites (head and neck), cancer of more than one type (multiple primary lesions), cancer of good prognosis (excluding lung, liver, gall bladder or pancreatic cancers), aggressive anticancer treatment and longer duration of pathologic proof (14 d). The results showed that concealing the diagnosis from cancer patients is still very common in Taiwan. Patient's sociodemographic background and disease-related factors were the most important patient characteristics related to their knowledge of the diagnosis.

Injection molding is a widely used polymer processing operation due to its ability to produce net-shaped components of good dimensional accuracy with relatively short cycle-times. This process is also employed in the production of short-fiber filled polymeric parts, combining the inherent processing advantages in injection-molding with the enhanced performance characteristics of fiber-filled composite materials. In contrast to continuous-fiber reinforced- or unidirectional short-fiber-composites, the properties of short-fiber-reinforced injection-molded (SFRIM) composites greatly depend on the orientation distribution of the fibers in the plastic matrix in addition to the properties of the component phases. One of the key ingredients in the application of computer-aided-engineering techniques to the production of SFRIM parts is the capability to determine the fiber orientation distribution as a result of the processing and also predict the mechanical properties in relation to the orientation distribution.

X-ray absorption near-edge structure (XANES) and x-ray emission spectroscopy (XES) measurements were used to investigate the effect of Mg doping in ZnO nanorods. The intensities of the features in the O K-edge XANES spectra of Zn{sub 1-x}Mg{sub x}O nanorods are lower than those of pure ZnO nanorods, suggesting that Mg doping increases the negative effective charge of O ions. XES and XANES spectra of O 2p states indicate that Mg doping raises (lowers) the conduction-band-minimum (valence-band-maximum) and increases the bandgap. The bandgap is found to increase linearly with the Mg content, as revealed by photoluminescence and combined XANES and XES measurements.

X-ray absorption near-edge structure (XANES) and scanning photoelectron microscopy (SPEM) measurements have been performed for Zn1−xCoxO and Zn1−xMgxO to elucidate the effects of the doping of Co and Mg, which have very different electronegativities, on the electronic structures of ZnO nanorods. The intensities of O K-edge near-edge features in the XANES spectra of Zn1−xCoxO and Zn1−xMgxO nanorods are found to be lower than those of ZnO, which suggests that both Co and Mg substitutions of the Zn ions enhance the effective charge on the O ion. The valence-band SPEM measurements show that Mg doping does not increase the density of near-Fermi-level states, which implies that Mg doping will not improve field emission of ZnO nanorods. It is surprising to find that both Co and Mg substitutions of Zn increase the numbers of O 2p dominated valence-band states, despite that Co and Mg have larger and smaller electronegativities than that of Zn.

Based upon a compilation of steady-shear and dynamic-shear viscosity data from the literature for polystyrene melts, an assessment has been made concerning the relative merits of the Cross and Carreau models in describing the shear-rate dependence of such viscosities. It is shown that the Cross model is decidedly more appropriate for PS of BMWD. Based upon master plots, it is demonstrated that the Cox-Merz relation applies to PS of both BMWD and NMWD. It is also shown that the Cox-Merz relation applies even into the second-Newtonian regime, withη∞ being independent ofMw and MWD. In addition, the applicability of the Prest-Porter-O'Reilly relationship between shear viscosity and recoverable shear compliance is corroborated in the case of PS of NMWD.