bluuebunny/crossref_metadata_2025_split huggingface dataset:
Arthroscopic treatment of osteochondral lesions of the talus
Authors: Robinson D. E. , Winson I. G. , Harries W. J. , Kelly A. J. 
Published: September 2003

We reviewed, retrospectively, 65 patients who had undergone arthroscopic treatment for osteochondral lesions of the talus. The 46 men and 19 women with a mean age at operation of 34.25 years, were followed up for a mean of 3.5 years. The medial aspect was affected in 45 patients and the lateral aspect in 20. All the lateral lesions and 35 (75%) of the medial lesions were traumatic in origin. Medial lesions presented later than lateral lesions (3 v 1.5 years) and had a much greater incidence of cystic change (46% v 8%). At follow-up, 34 patients had achieved a good result, and 17 and 14 fair and poor results, respectively. Of the 14 poor results, 13 involved medial lesions. Cystic lesions had a poor outcome in 53% of patients. Excision and curettage led to better results than excision and drilling of the base. Further arthroscopic surgery for patients with a poor result was disappointing. There was no association between outcome and the patient’s age.
The natural history of spontaneous osteonecrosis of the medial tibial plateau
Authors: Satku K. , Kumar V. P. , Chong S. M. , Thambyah A. 
Published: September 2003

The natural history of spontaneous osteonecrosis of the medial tibial plateau remains controversial and incomplete. We have studied 21 patients (aged between 53 and 77 years) with clinical and scintigraphic features of spontaneous osteonecrosis of the medial tibial plateau who were observed prospectively for at least three years (37 months to 8.5 years). The mean duration of follow-up was 5.6 years. The mean duration of symptoms at presentation was 4.7 weeks (3 days to 12 weeks). Radiographs of the affected knee at the first visit were normal in 15 patients and mildly arthritic in six. The characteristic radiographic lesion of osteonecrosis was noted at presentation in five of the mildly arthritic knees and during the evolution of the disease in eight of the radiographically normal knees. During the follow-up, subchondral sclerosis of the affected medial tibial plateau was noted in 16 knees. There are three distinct patterns of outcome: 1) acute extensive collapse of the medial tibial plateau in two knees within three months of onset; 2) rapid progression to varying degrees of osteoarthritis in 12 knees, in eight within a year, in all within two years and deterioration of the pre-existing osteoarthritis in three; and 3) complete resolution in four knees, two of which were normal at presentation and two mildly osteoarthritic. The two patients with acute extensive collapse and three who had rapid progression to severe osteoarthritis required total knee arthroplasty. We conclude that osteonecrosis of the medial tibial plateau progresses in most cases to significant degenerative disease of the knee.
Thermal and mechanical properties of plasticized poly(L‐lactic acid)
Authors: Baiardo Massimo , Frisoni Giovanna , Scandola Mariastella , Rimelen Michel , Lips David , Ruffieux Kurt , Wintermantel Erich 
Published: September 2003

AbstractAcetyl tri‐n‐butyl citrate (ATBC) and poly(ethyleneglycol)s (PEGs) with different molecular weights (from 400 to 10000) were used in this study to plasticize poly(L‐lactic acid) (PLA). The thermal and mechanical properties of the plasticized polymer are reported. Both ATBC and PEG are effective in lowering the glass transition (Tg) of PLA up to a given concentration, where the plasticizer reaches its solubility limit in the polymer (50 wt % in the case of ATBC; 15–30 wt %, depending on molecular weight, in the case of PEG). The range of applicability of PEGs as PLA plasticizers is given in terms of PEG molecular weight and concentration. The mechanical properties of plasticized PLA change with increasing plasticizer concentration. In all PLA/plasticizer systems investigated, when the blend Tg approaches room temperature, a stepwise change in the mechanical properties of the system is observed. The elongation at break drastically increases, whereas tensile strength and modulus decrease. This behavior occurs at a plasticizer concentration that depends on the Tg‐depressing efficiency of the plasticizer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1731–1738, 2003
Use of rheological compatibility criteria to study SBS modified asphalts
Authors: M Yvonne Becker , Müller Alejandro J. , Rodriguez Yajaira 
Published: September 2003

AbstractPolymer‐modified asphalts (PMAs) were prepared using Bachaquero asphalt and styrene–butadiene–styrene (SBS) type copolymers. Their rheological behavior was compared to that of unmodified asphalt and of a compatible commercial PMA. Materials were submitted to frequency sweeps between 10−1and 102rad/s from 0 to 50°C. Storage stability tests were performed for 72 h at 160°C. Ring and ball softening points from the top and the bottom of the blends were compared and were used along with fluorescence microscopy to evaluate stability. Samples prepared with styrene–ethylene–butylene–styrene (SEBS) showed improved compatibility and stability as compared with SBS‐modified asphalts, probably because of a higher stability to thermal degradation from the absence of double bonds. An additional improvement in stability and compatibility was observed for SEBS functionalized with maleic anhydride (SEBS‐g‐MAH)–modified blends. Better compatibility, however, did not improve rheological behavior at low temperatures. The systems studied are so complex from a chemical point of view that the rheological criteria normally used to predict compatibility of polyblends did not give enough information regarding the compatibility of the modified asphalts. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1772–1782, 2003
Study of blend films from chitosan and hydroxypropyl guar gum
Authors: Xiao Chaobo , Zhang Jinhua , Zhang Zhenjun , Zhang Lina 
Published: September 2003

AbstractIn this study blend films of chitosan (CH) and hydroxypropyl guar gum (HGG) were prepared using a conventional solvent‐casting technique and were dried at room temperature. Their miscibility and other properties were studied by Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, scanning electron microscopy, differential thermal analysis, ultraviolet analysis, and tensile strength tests. The physical and thermal properties of the films depended on the blending ratio. The maximum tensile strength and breaking elongation values achieved were 58.94 MPa and 17.25%, respectively, with a 60% content of HGG. Thermal stability also was improved, and the blend film containing 60% HGG had greater thermal stability than did the other blend and pure CH films. In addition, the best optical transparence was observed from 500 to 800 nm in the blend film containing 60% HGG. The results indicate that intermolecular interactions that resulted from hydrogen bonding between CH and HGG occurred in the blend films. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1991–1995, 2003
Antimicrobial activity of a monomer and its polymer based on quinolone
Authors: Moon Woong‐Sig , Chul Kim Jae , Chung Kyoo‐Hyun , Park Eun‐Soo , Kim Mal‐Nam , Yoon Jin‐San 
Published: September 2003

AbstractAn acryl monomer containing the quinolone moiety was synthesized and then polymerized with azobisisobutyronitrile in a dimethylformamide solution. The resulting polymer as well as the corresponding monomer exhibited an excellent antibacterial activity. The poly(acrylated quinolone) (PQ) was compounded with other ordinary synthetic polymers such as low‐density polyethylene (LDPE), poly(butylene succinate) (PBS), poly(methyl methacrylate) (PMMA), maleated polypropylene (PPMA), and polycaprolactone (PCL). The polymer blends reduced the viable cell number significantly on contact during the shake flask test even when the PQ content was as low as 1 wt %. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1797–1801, 2003
Hole injection initiated by ionic conduction in electrically stressed insulating polymers
Authors: Kao Kwan C. , Tu Demin 
Published: September 2003

AbstractA new mechanism leading to hole injection into insulating polymers under normal operating fields is presented. In general, it is unlikely that holes can be injected into large band‐gap insulating materials under normal operating fields less than 1 MV cm−1, particularly for materials that are not in the form of thin films. However, insulating polymers consist of a large amount of various unavoidable ionic impurities, so ionic conduction plays an important role in their electrical properties. The presence of such ions modifies the field distribution in the material with the tendency of enhancing the field toward the anode, thus increasing the probability for hole tunneling from the anode to the material. The appearance of positive space charge near the anode after a prolonged period of electrical stressing, as observed by many investigators, may be considered as the experimental evidence of the mechanism. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1864–1867, 2003
Correlation between limiting oxygen index and phosphorus/nitrogen content of cotton fabrics treated with a hydroxy‐functional organophosphorus flame‐retarding agent and dimethyloldihydroxyethyleneurea
Authors: Wu Weidong , Yang Charles Q. 
Published: September 2003

AbstractThe combination of a hydroxyl‐functional organophosphorus flame‐retarding agent (FR) and dimethyloldihydroxyethyleneurea (DMDHEU) was used as a durable flame‐retardant finish system for cotton fabrics. DMDHEU functions as a binder between FR and cotton cellulose, thus making this flame‐retarding system durable to home laundering. DMDHEU also provides nitrogen to this system, therefore enhances its performance. Limiting oxygen index (LOI) is one of the most commonly used parameters to indicate the flammability of textiles and other polymeric materials. In this research, we investigated the correlation between LOI and phosphorus/nitrogen content on the cotton fabric treated with that durable flame‐retardant system. Phosphorus concentration on the fabric was analyzed by inductively coupled plasma atomic emission spectroscopy, whereas the nitrogen content was determined indirectly by measuring the carbonyl band intensity in the infrared spectra of the treated fabric. We developed a statistical model to predict LOI of the cotton fabric treated with FR and DMDHEU based on the phosphorus concentration and the intensity of carbonyl band of DMDHEU on cotton. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1885–1890, 2003
Preparation and characterization of poly(styrene butylacrylate) latex/nano‐ZnO nanocomposites
Authors: Xiong Mingna , Gu Guangxin , You Bo , Wu Limin 
Published: September 2003

AbstractPoly(styrene butylacrylate) latex/nano‐ZnO composites were prepared by blending poly(styrene butylacrylate) latex with a water slurry of nano‐ZnO particles, and the effects of certain parameters, such as particle size, dispersant type, dispersing time and others, on the dispersibility, mechanical properties, ultraviolet (UV) shielding and near infrared (NIR) shielding were investigated with transmission electron microscopy (TEM), an Instron testing machine, dynamic mechanical analysis and ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) spectrophotometry. TEM observation showed that dispersants with long chains are better than those with short chains at enhancing the dispersibility of nano‐ZnO particles in a matrix; extending dispersing time also improves the dispersibility of nano‐ZnO particles in a matrix. Instron tests showed that the nanocomposite polymers embedded with nano‐ZnO particles had much higher tensile strength than the corresponding composite polymers with micro‐ZnO particles. As the nano‐ZnO content increased, the temperature of glass transition (Tg) of the nanocomposite polymer embedded with 60 nm ZnO particles first increased then decreased, but 100 nm ZnO and micro‐ZnO particles seemed to have no influence on the Tg of the composite polymers. The better dispersibility of nano‐ZnO particles resulted in higher Tg values. Increasing nano‐ZnO content or dispersibility could enhance the UV shielding properties of the nanocomposite polymers, and 60 nm ZnO particles could more effectively shield UV rays than 100 nm ZnO particles. Micro‐ZnO particles basically had no effect on the UV absorbance of the composite polymers. A blue‐shift phenomenon was observed at 365 nm when nano‐ZnO particles were present in the nanocomposite polymers. NIR analysis indicated that as nano‐ZnO content increased, the NIR shielding of the nanocomposite polymers increased, but the NIR shielding properties seemed to be more influenced by particle size than by the nano‐effect. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1923–1931, 2003
Mechanical properties and microstructure of poly(ethylene terephthalate) microfiber prepared by carbon dioxide laser heating
Authors: Suzuki Akihiro , Mochizuki Noriaki 
Published: September 2003

AbstractWe determined that a poly(ethylene terephthalate) microfiber was easily obtained by irradiating a carbon dioxide laser to an annealed fiber. The annealed fiber was prepared by zone drawing and zone annealing. First, an original fiber was zone drawn at a drawing temperature of 90°C under an applied tension of 4.9 MPa, and the zone‐drawn fiber was subsequently zone annealed at 150°C under 50.9 MPa. The zone‐annealed fiber had a degree of crystallinity of 48%, a birefringence of 218.9 × 10−3, tensile modulus of 18.8 GPa, and tensile strength of 0.88 GPa. The microfiber prepared by laser heating the zone‐annealed fiber had a diameter of 1.5 μm, birefringence of 172.8 × 10−3, tensile modulus of 17.6 GPa, and tensile strength of 1.01 GPa. The draw ratio estimated from the diameter was 9165 times; such a high draw ratio has thus far not been achievable by any conventional drawing method. Microfibers may be made more easily by laser heating than by conventional technologies such as conjugate spinning. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1955–1958, 2003
Modeling dynamic inconsistency with a changing reference point
Authors: Barkan Rachel , Busemeyer Jerome R. 
Published: September 2003

AbstractA rational principle of decision making called dynamic consistency was tested by presenting decision makers with a sequence of two gambles. The first gamble was obligatory. Before playing the first gamble, participants were asked to make a planned choice as to whether they would take the second gamble. After experiencing the actual results of the first gamble, decision makers were asked to make a final choice regarding the second gamble. Dynamic consistency requires agreement between the planned and final choices. Violations of dynamic consistency were observed, e.g. anticipating a gain in the first gamble, decision makers planned to take the second gamble; after experiencing the gain, they changed their minds and rejected the second gamble. Two models of dynamic inconsistency were compared. One assumes that experience shifts the reference point and changes the utility associated with the gamble; another assumes that experience changes the subjective probability associated with the gamble. The reference point model provided the best account for the findings. Copyright © 2003 John Wiley & Sons, Ltd.
The lure of choice
Authors: Bown Nicola J. , Read Daniel , Summers Barbara 
Published: September 2003

AbstractWe report three studies demonstrating the ‘lure of choice’ people prefer options that allow them to take further choices over those that do not, even when the extra choices cannot improve the ultimate outcome. In Studies 1 and 2, participants chose between two options: one solitary item, and a pair of items between which they would then make a further choice. Consistent with the lure of choice, a given item was more likely to be the ultimate choice when it was initially part of a choice pair than when it was offered on its own. We also demonstrate the lure of choice in a four‐door version of the Monty Hall problem, in which participants could either stick with their original choice or switch to one of two unopened doors. Participants were more likely to switch if they could first ‘choose to choose’ between the two unopened doors (without immediately specifying which) than if they had to choose one door straightaway. We conclude by suggesting that the lure of choice is due to a choice heuristic that is very reliable in the natural world, but much less so in a world created by marketers. Copyright © 2003 John Wiley & Sons, Ltd.
The role of affect in the WTA/WTP disparity
Authors: Peters Ellen , Slovic Paul , Gregory Robin 
Published: September 2003

AbstractFour studies demonstrated robust within‐ and between‐subject differences in willingness‐to‐pay (WTP) and willingness‐to‐accept (WTA) measures of the value of lottery tickets. Buyers and sellers attended to different numerical cues and interpreted the same numbers differently when setting these two kinds of monetary values. Affective influences appeared to guide the valuation process. Buyers with stronger positive feelings about owning a ticket were willing to pay more for a ticket; sellers with stronger negative feelings about no longer having a ticket required a greater minimum payment in exchange for their ticket. In addition, the WTA/WTP disparity tended to be greater for more affectively‐laden lottery tickets. The results suggest that WTA and WTP prices are constructed using salient numerical cues and affective feelings. Copyright © 2003 John Wiley & Sons, Ltd.
Anti-inflammatory drugs, analgesics and the risk of perforated colonic diverticular disease
Authors: Morris C R , Harvey I M , Stebbings W S L , Speakman C T M , Kennedy H J , Hart A R 
Published: September 2003

Abstract

Background
Acute perforated colonic diverticular disease has a mortality rate of up to 30 per cent, but little is known about its aetiology. The aim of this study was to test the hypothesis that three classes of drugs, namely non-steroidal anti-inflammatory drugs (NSAIDs), opioid analgesics and corticosteroids, are risk factors for perforated diverticular disease.

Methods
All patients with confirmed perforated colonic diverticular disease were identified over a 5-year period in two hospitals in Norfolk, UK. Two control groups were selected and matched for age, sex and hospital of admission. Data on medication use were obtained from hospital records. Odds ratios for each drug were calculated using conditional logistic regression.

Results
Opioid analgesics, NSAIDs and corticosteroids were all positively associated with perforated colonic diverticular disease. The odds ratio for opioid analgesics was 1·8 (95 per cent confidence interval (c.i.) 1·1 to 3·0) in the analysis with ophthalmology controls and 3·1 (95 per cent c.i. 1·8 to 5·5) in that with dermatology controls. Respective odds ratios for NSAIDs were 4·0 (95 per cent c.i. 2·1 to 7·6) and 3·7 (95 per cent c.i. 2·0 to 6·8), and those for corticosteroids were 5·7 (95 per cent c.i. 2·2 to 14·4) and 7·8 (95 per cent c.i. 2·6 to 23·3).

Conclusion
Opioid analgesics, NSAIDs and corticosteroids are all positively associated with perforated colonic diverticular disease. The consistency of these associations, together with plausible biological mechanisms, suggests that these drugs may have a causative role in this condition.
Randomized clinical trial comparing epidural anaesthesia and patient-controlled analgesia after laparoscopic segmental colectomy
Authors: Senagore A J , Delaney C P , Mekhail N , Dugan A , Fazio V W 
Published: September 2003

Abstract

Background
This randomized clinical trial compared the use of thoracic epidural anaesthesia–analgesia (TEA) with morphine patient-controlled analgesia (PCA) for pain relief after laparoscopic colectomy.

Methods
Patients scheduled for segmental laparoscopic colectomy were randomized to receive TEA or PCA. Patients in the TEA group received bupivacaine and fentanyl before incision and after surgery by continuous infusion for 18 h. Patients in the PCA group self-administered morphine using an intravenous pump. The postoperative care plan was otherwise identical for the two groups. Postoperative pain was measured during ambulation using a visual analogue pain score.

Results
The study included 38 patients (18 TEA, 20 PCA), 16 of whom underwent right hemicolectomy or ileocolectomy and 22 sigmoid colectomy. Operating times, patient weight and distribution of American Society of Anesthesiologists grade were similar in the two groups. The mean(s.e.m.) total dose of drugs administered was 64(41) mg morphine in the PCA group, and 79(42) mg bupivacaine and 205(140) µg fentanyl in the TEA group. Postoperative pain scores were significantly better in the TEA group at 6 h (mean(s.e.m.) 2·2(0·4) versus 6·6(0·5) with PCA; P = 0·001) and 18 h (2·2(0·3) versus 4·0(0·4); P = 0·003). Hospital stay was similar in the two groups.

Conclusion
TEA significantly improved early analgesia following laparoscopic colectomy but did not affect the length of hospital stay.
Evaluation of POSSUM and P-POSSUM scoring systems in assessing outcome after laparoscopic colectomy
Authors: Senagore A J , Delaney C P , Duepree H J , Brady K M , Fazio V W 
Published: September 2003

Abstract

Background
The purpose of this study was to compare the actual and predicted risk-adjusted morbidity and mortality after laparoscopic colectomy (LAC) calculated using both the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) and Portsmouth POSSUM (P-POSSUM) scoring systems.

Methods
All patients who underwent LAC performed by a single surgeon between March 1999 and December 2000 were analysed. The observed morbidity and mortality rates were compared with those predicted by the POSSUM scoring system, and the observed mortality rate with that predicted by P-POSSUM. The operative severity component of the operative score was sequentially decreased from 4 (standard score for open colectomy) to 2, then 1, in an attempt to correct overprediction.

Results
Two hundred and fifty-one consecutive patients underwent LAC, with a conversion rate of 8·0 per cent. The morbidity rate (6·8 per cent) was significantly lower than the predicted rates calculated with an operative score of 4 or 2 (12·4 per cent, P &lt; 0·001; 9·6 per cent, P = 0·001), but was fully corrected with an operative score of 1 (7·0 per cent, P = 0·325). The observed mortality rate (0·8 per cent) was significantly different from the expected mortality rates calculated using either uncorrected POSSUM (9·6 per cent, P = 0·001) or P-POSSUM (3·5 per cent, P = 0·001). POSSUM (2·6 per cent, P = 0·007) continued to overpredict mortality but P-POSSUM (1·0 per cent, P = 0·001) accurately predicted mortality with an operative score of 1.

Conclusion
LAC appeared to be associated with lower morbidity and mortality rates than those predicted by the POSSUM scoring system, and with a lower mortality rate than that predicted using the P-POSSUM system.