Improvements of fiberboard properties through fiber activation and subsequent copolymerization with vinyl monomer

High-temperature refined thermomechanical pulp (MDF fiber) was dried, extracted with neutral organic solvent, and reacted with three types of electrophilic reagents (glycidyl methacrylate, maleic anhydride, and succinic anhydride). The adducts formed were further reacted in a hot press with a vinyl monomer in the presence of a free-radical initiator (benzoyl peroxide). Well-conformed boards were produced by the process. Modified boards showed significant improvement in thickness swelling as well as in strength properties compared to control phenol–formaldehyde boards. Glycidyl methacrylate modified/methyl methacrylate boards were the most stable toward the wet-and dry-exposure cycles, whereas succinic anhydride/methyl methacrylate boards showed the lowest water absorption. © 1994 John Wiley & Sons, Inc.     

Renal failure in multiple myeloma: presenting features and predictors of outcome in 94 patients from a single institution

BACKGROUND: Twenty percent of patients with multiple myeloma (MM) have renal failure. OBJECTIVE: To analyze the presenting features, the response to therapy, and the factors associated with renal function recovery and survival in 94 patients with MM and renal failure. PATIENTS AND METHODS: Medical records of patients from our institution with MM and renal failure diagnosed between January 1969 and December 1994 were reviewed. The statistical methods consisted of Kaplan-Meier survival curves, the log-rank test, logistic regression analysis, and the Cox proportional hazards model for survival analysis. RESULTS: Renal failure was observed in 94 (22.2%) of 423 patients. Patients with renal failure had more advanced disease than the others. Patients with renal failure had a lower response rate to chemotherapy than those with normal renal function (39% vs 56%; P<.001). However, when patients dying within the first 2 months of treatment were excluded, no significant differences in the response rate were found between patients with renal failure and those with normal renal function. Renal function recovery was observed in 26% of patients. Serum creatinine level (<354 micromol/L [<4 mg/dL]), serum calcium level (> or =2.88 mmol/L [> or = 11.5 mg/dL]), and amount of proteinuria (< 1 g/24 h) were associated with renal function recovery. Patients who recovered renal function had a median survival of 28 months vs 4 months for those with nonreversible renal failure (P<.001). In the multivariate analysis, only serum creatinine level (P=.003) and response to chemotherapy (P<.001) were correlated with survival. CONCLUSIONS: Renal failure was present in almost one fourth of patients with MM. Patients with reversible renal failure had longer survival than those not recovering renal function. When patients dying within the first 2 months of treatment were excluded, the response rate was not affected by renal function. Factors associated with renal function recovery were degree of renal failure, presence of hypercalcemia, and amount of proteinuria. Response to chemotherapy and severity of renal failure were the only independent factors associated with survival.     

Treatment of rheumatoid arthritis with recombinant human interleukin-1 receptor antagonist

OBJECTIVE: To evaluate the efficacy and safety of interleukin-1 receptor antagonist (IL-1Ra) in patients with rheumatoid arthritis (RA). METHODS: Patients with active and severe RA (disease duration <8 years) were recruited into a 24-week, double-blind, randomized, placebo-controlled, multicenter study. Doses of nonsteroidal antiinflammatory drugs and/or oral corticosteroids (< or =10 mg prednisolone daily) remained constant throughout the study. Any disease-modifying antirheumatic drugs that were being administered were discontinued at least 6 weeks prior to enrollment. Patients were randomized to 1 of 4 treatment groups: placebo or a single, self-administered subcutaneous injection of IL-1Ra at a daily dose of 30 mg, 75 mg, or 150 mg. RESULTS: A total of 472 patients were recruited. At enrollment, the mean age, sex ratio, disease duration, and percentage of patients with rheumatoid factor and erosions were similar in the 4 treatment groups. The clinical parameters of disease activity were similar in each treatment group and were consistent with active and severe RA. At 24 weeks, of the patients who received 150 mg/day IL-1Ra, 43% met the American College of Rheumatology criteria for response (the primary efficacy measure), 44% met the Paulus criteria, and statistically significant improvements were seen in the number of swollen joints, number of tender joints, investigator's assessment of disease activity, patient's assessment of disease activity, pain score on a visual analog scale, duration of morning stiffness, Health Assessment Questionnaire score, C-reactive protein level, and erythrocyte sedimentation rate. In addition, the rate of radiologic progression in the patients receiving IL-1Ra was significantly less than in the placebo group at 24 weeks, as evidenced by the Larsen score and the erosive joint count. IL-1Ra was well tolerated and no serious adverse events were observed. An injection-site reaction was the most frequently observed adverse event, and this resulted in a 5% rate of withdrawal from the study among those receiving IL-1Ra at 150 mg/day. CONCLUSION: This study confirmed both the efficacy and the safety of IL-1Ra in a large cohort of patients with active and severe RA. IL-1Ra is the first biologic agent to demonstrate a beneficial effect on the rate of joint erosion.     

The impact of a new emotional self-management program on stress, emotions, heart rate variability, DHEA and cortisol

In an attempt to develop an assay for the susceptibility of plasma lipids to oxidation, we have studied the kinetics of copper-induced oxidation in diluted serum and plasma prepared with different anticoagulants (heparin, citrate and EDTA) by monitoring the absorbance of oxidation-products at several wavelengths. These studies revealed the complex and interrelated effects of the water-soluble antioxidant ascorbic acid, citrate and chloride ions on the kinetics of copper-induced oxidation of plasma lipids. Specifically, the onset of oxidation induced by copper-citrate chelates is only slightly affected by chloride ions and is accelerated upon increasing the copper concentration. By contrast, in the absence of citrate, the lag preceding oxidation in diluted serum or plasma (but not the maximal rate of oxidation) depends markedly on the chloride concentration in the diluting medium. In the absence of Cl-, the lag preceding oxidation is a decreasing saturable function of copper concentration, whereas in a normal phosphate-buffered saline solution (PBS), the lag shows a biphasic dependence on copper concentration such that at copper concentrations above 10-30 microM (depending on the extent of plasma dilution), increasing the concentration of copper results in prolongation of the lag. This dependence of copper-induced oxidation on the concentration of copper is not observed for dialyzed serum unless ascorbic acid is added. Our interpretation of these results is that water-soluble reductants and chloride ions act synergistically to stabilize Cu+, on the expense of Cu2+. Quenching of free radicals by Cu+ may be responsible for the prolongation of the lag at high copper concentrations, with no reduction of the maximal rate of oxidation. In spite of the complex dependencies described above, spectrophotometric monitoring of the kinetics of oxidation of plasma lipids, under 'optimized conditions' (50-fold diluted serum, in PBS containing 720 microM sodium citrate and 100 microM copper), agrees with independent measurements of the consumption of polyunsaturated fatty acids. Hence, the spectroscopic method may become useful for evaluation of the susceptibility of plasma lipids to oxidation. This possibility, however, has yet to be elucidated through investigations of the correlation between the susceptibility of serum lipids to copper-induced oxidation in vitro and clinical factors of significance.     

The effect of rat anterior cingulate inactivation on cognitive flexibility.

The present experiment investigated the effects of muscimol injections into the rat dorsal anterior cingulate on the acquisition and reversal learning of a 4-choice odor discrimination. Long-Evans rats were trained to dig in cups that contained distinct odors. In the odor discrimination, one odor cup contained a cereal reinforcement in acquisition whereas a different odor cup contained a cereal reinforcement in reversal learning. The other 2 odor cups were never associated with reinforcement. Bilateral infusions of the gamma aminobutyric acid-A agonist muscimol did not impair acquisition of the odor discrimination but impaired reversal learning in a dose-dependent manner. During reversal learning, dorsal anterior cingulate inactivation did not lead to perseveration but selectively increased errors to the odor cups that were never reinforced. These findings suggest that the dorsal anterior cingulate supports learning when conditions require a shift in choice patterns and may enhance cognitive flexibility by decreasing interference of irrelevant stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of coupling agents on the mechanical and physical properties of oil palm empty fruit bunch–polypropylene composites

Oil palm empty fruit bunch–polypropylene (EFB‐PP) composites have been produced using a twin‐screw extruder as the compounding equipment. Two levels of EFB were employed, 40 % and 60 % of the total weight of the sample. Three types of coupling agent, maleic anhydride‐modified polypropylene (commercial name Epolene E‐43), polymethylene(polyphenyl isocyanate) (PMPPIC) and 3‐(trimethoxysilyl)‐propylmethacrylate (TPM), were used. Overall, all coupling agents imparted considerable improvements in the flexural properties, E‐43 showing the highest enhancement. However, only E‐43 was observed to improve impact strength and tensile properties of the composites. All composites with coupling agents showed lower water absorption and thickness swelling. The absorption and swelling decreased as the loading of the coupling agents was increased. © 2000 Society of Chemical Industry     

Noise analysis of the UHF RFID system

Noise is one of the most important parameters in designing a radio frequency (RF) system. Especially in ultra-high frequency (UHF) RF identification (RFID) systems noise plays and important role. This is because the noise performance of the receiver chain is defined not only by the intrinsic noise of the receiver, but also by the large self-jammer signal. This self-jammer signal on the one hand requires that the receiver is designed for high input dynamic range which increases the intrinsic noise of the receiver. On the other hand this self-jammer signal through the effects of reciprocal mixing and range correlation contributes significantly to the total noise of the receiver. To our knowledge this is the first work that deals in detail with the amplitude and phase noise in a UHF RFID system.     

A comparison study of lignocellulosic–thermoplastic composites prepared from different compounding techniques

A comparison study was carried out to determine the effect of different types of compounding technique, i.e., internal mixer, twin screw extruder, and high speed mixer in the preparation of kenaf‐polypropylene composite. The effect of percentage kenaf loading and particle size of kenaf (core) on the flexural properties of the composite was investigated. From the results, the incorporation of kenaf, regardless of particle size had resulted in the reduction of flexural strength of the composite. However, flexural modulus of the composites increased as the percentage of kenaf loading was increased due to the increasing of the stiffness contributed by kenaf fiber. Composites produced from internal mixer had displayed higher flexural properties as compared to those prepared from high speed mixer and twin screw extruder. It was believed that this phenomenon was attributed to the effectiveness of internal mixer with a better compounding mechanism which improved the wetting and distribution on kenaf within the polypropylene matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Splenomegalic pancytopenia of probable immune origin: cure after treatment with glucocorticoids

Two female patients of 54 and 48 years, respectively, with pancytopenia and splenomegaly of probable immune origin are reported. The first presented anemic syndrome and fever, and the second bleeding. In both cases large sized splenomegaly was found on physical examination. Serologic and immunologic studies excluded chronic infection or systemic autoimmune disease. Bone marrow biopsy showed hematopoietic hyperplasia with lymphoid nodules and reticulin fibrosis. Treatment with glucocorticoids and splenectomy was performed in one case and only glucocorticoids were administered in the other case with the cytopenias disappearing and the bone marrow becoming normocellular. Reactive follicular hyperplasia was observed in the white pulp of the spleen in one of the patients, as were abundant macrophagic activity in the red pulp, and myeloid metaplasia. The patients remain asymptomatic at 4 and 12 years of follow up. The origin of the process was attributed probably to an immune etiology and differential diagnosis with idiopathic myelofibrosis and non tropical idiopathic splenomegaly must be considered.     

The stainless steel screw as an orthopaedic implant

The study reported here dealt with the metallographical inspection and analysis of corrosion behavior of screws for mild Slipped Capital Femoral Epiphysis (SCFE), which is a serious orthopedical problem in early adolescence. The screws were fabricated from low carbon, austenitic grade stainless steel type 316L (AISI) with 1600 ppm of nitrogen (316LN2). They were clinically tested in a nearly 25‐year‐long study where patients in early adolescence were operated with these screws with the fixation in situ. Since the results obtained in all patients were similar, we present the results obtained in screws removed after 3 years of implantation from a 14‐year‐old boy. Metallographical inspection results reveal that a low content of carbon in the SS 316LN2, and annealing this material at a high temperature ensures the monophasic microstructure of austenitic grains. In the grains twin bands that appeared during mechanical deformation were observed. As the hardness measured at the stalk (262 HV) was lower than that measured at the head of the screw (293 HV) it was concluded that cold mechanical deformation of the head was much more extensive than that of the stalk. Accordingly, corrosion of the head could be more probable than that of the stalk. Corrosion behavior of the screw in simulated physiological media (0.9% NaCl solution), carried out by the electrochemical method, gave an E_corr of ?0.124 V (vs. SCE), corrosion current density of 21 nA/cm², and corrosion rate of 0.010 ± 0.005 mpy. This low corrosion rate indicates that SS 316LN2 expresses relatively high corrosion resistance in a saline solution. However, potentiodynamic polarization measurements, where the specimen was driven to more than 1.8 V above the E_corr., showed that in the region between ?0.1 and 0.15 V the specimen corroded, while around 0.2 V a small valley appeared where passivation proceeded. The narrow passive region between 0.15 and 0.25 V indicated that chlorides prevented the formation of thick protecting films. With potentials more positive than 0.3 V the passivating film broke down and the specimen began to corrode. These data indicate that SS 316LN2 can not be effectively protected by passivation since it is not corrosion resistant in a chloride containing environment.