bluuebunny/crossref_metadata_2025 huggingface dataset:
Building-integrated photovoltaics: effect on the cooling load component of building façades
Authors: Yang H , Burnett J , Zhu Z
Published: November 2003

The cooling load component of building-integrated photovoltaic (PV) walls has been investigated by numerical simulation of heat transfer across PV-walls. The cooling load component across the PV façades is predicted by the room transfer function method, based on the predicted heat gains for three cases at different locations (Beijing, Shanghai and Hong Kong). The simulation results are compared with the cooling load components of conventional walls that are directly exposed to the sun. The comparison indicates that the cooling load component reduction ratio due to photovoltaic integration ranges from 33% to 52% for a typical day in a year.
Embodied energy analysis of aluminium-clad windows
Authors: Asif M , Davidson A , Muneer T
Published: November 2003

This article provides an overview of energy loads associated with the application of powder coated aluminium profiles on the exterior wooden surface of double glazed windows. The entire powder coating process has been analysed to measure its energy and environmental contribution towards window cladding. Materials involved in aluminium clad windows have been analysed for their energy impacts. The energy embodied in a standard double glazed 1.2 m × 1.2 m aluminium clad window has been calculated, and is quantified as 1459 MJ, 1967 MJ, and 5.96 GJ respectively for argon, krypton and xenon infill gases. The energy consumed in powder coating the window cladding has been estimated to be 27 MJ and the total embodied energy of adding aluminium cladding to the window has been evaluated as 724 MJ.
Improvements in investment casting with stereolithography patterns
Authors: Hague R , Dickens P M
Published: November 2003

The use of investment casting to gain functional metal parts from stereolithography (SL) models is well documented. However, despite the thousands of metal castings produced, the original stereolithography build structures that were designed for investment casting have only been partly successful in combating the effects of the thermal expansion SL resins. Investment casting foundries still have to alter their existing techniques and, significantly, are dewaxing shells containing SL models in the flash furnace rather than the steam autoclave.

This paper describes how a greater understanding has been established of why SL investment casting patterns are causing the shells to crack. Theoretical and practical stress analysis, utilizing finite element analysis and strain gauge techniques, has given a much clearer picture of the failure modes of the ceramic shells and SL models. This has led to a set of criteria for the design of build structures that allows the successful autoclaving and subsequent casting of stereolithography models.

Details of the background research, stress analysis and design criteria are presented along with a new design of internal build structure that allows the successful autoclaving and casting of stereolithography models.
A conceptual design tool: A sketch and fuzzy logic based system
Authors: Qin S-F , Wright D K , Jordanov I N
Published: November 2003

A real-time sketch and fuzzy logic based prototype system for conceptual design has been developed. This system comprises four phases. In the first one, the system accepts the input of online free-hand sketches, and segments them into meaningful parts by using fuzzy knowledge to detect corners and inflection points on the sketched curves. The fuzzy knowledge is applied to capture user's drawing intention in terms of sketching position, direction, speed and acceleration. During the second phase, each segmented subpart (curve) can be classified and identified as one of the following two-dimensional primitives: straight lines, circles, circular arcs, ellipses, elliptical arcs or B-spline curves. Then, two-dimensional topology information (connectivity, unitary constraints and pairwise constraints) is extracted dynamically from the identified two-dimensional primitives. From the extracted information, more accurate two-dimensional geometry can be built up by a two-dimensional geometric constraint solver. The two-dimensional topology and geometry information is then employed to further interpretation of a three-dimensional geometry. The system can not only accept sketched input but also users’ interactive input of two- and three-dimensional primitives. This makes it friendly and easier to use, in comparison with ‘sketched input only’ or ‘interactive input only’ systems. Finally, examples are given to illustrate the system.
Adsorption of Mercury(II) Ions by Poly(Hydroxyethylmethacrylate) Adsorbents with Thiazolidine Groups
Authors: Arpa Ç. , Sağlam A. , Bektał S. , Patir S. , Genç Ö. , Denizli A.
Published: November 2003

A wide variety of adsorbents has been reported in the literature for heavy metal adsorption. We have recently developed a new polymer system for the removal of contaminant heavy metal ions from aquatic systems. Thus, poly(hydroxyethylmethacrylate) (PHEMA) microbeads carrying thiazolidine (0.318 mmol/g) were prepared for the removal of different amounts of mercury(II) ions (50–900 mg/l) from aqueous solutions and at different pH values (3.0–7.0). Adsorption rates were high with adsorption equilibria being reached within 10 min. The adsorption of Hg(II) ions on to the thiazolidine-immobilized microbeads from single solutions amounted to 1.11 mmol/g. The formation constant of the thiazolidine–metal ion complex was investigated by the method of Ružić. The calculated value of the stability constant was 9.11 × 105 l/mol for the Hg(II)–thiazolidine complex. PHEMA microbeads carrying thiazolidine may be regenerated by washing with a solution of hydrochloric acid (0.05 M). The maximum desorption ratio was as high as 99%. These PHEMA microbeads may be used repeatedly for more than three adsorption/desorption cycles without any considerable loss in adsorption capacity.
Sorption of Metal Ions on a Mixed Oxide [0.5 M SiO2:0.5 M Fe(OH)3]
Authors: Mustafa S. , Dilara B. , Naeem A. , Rahana N. , Shahida P.
Published: November 2003

The sorption of Zn2+, Ni2+, Cd2+, Ca2+ and Mg2+ ions on to a mixed oxide of iron and silicon was found to increase with increasing temperature, concentration and pH of the system. The selectivity of this mixed oxide was Cd2+ ≥ Zn2+ ≥ Ni2+ > Ca2+ > Mg2+, indicating that the mixed oxide was more selective as an exchanger towards Cd2+ ions relative to its components, SiO2 and Fe(OH)3. The sorption data fitted the linear forms of the Kurbatov and Langmuir adsorption equations. The sorption of metal cations was accompanied by the release of H+ ions to the bulk phase. On average 1 mol H+ was released for every cation sorbed. The values of the binding constants were used to estimate the apparent thermodynamic parameters, ΔH and ΔS. The phenomenon of enthalpy/entropy compensation showed that the adsorption of metal ions by the mixed oxide occurred typically through a cation-exchange mechanism.
Test of Some Aspects of Modelling the Sorption of Hydrophobic Compounds in Soils
Authors: Buszewski Bogusław , Zbytniewski Radosław
Published: November 2003

A study was carried out on the sorption of the herbicide linuron in podzolic soil (one of the typical soils of Poland), the sorption isotherms being obtained using batch equilibrium studies. Modelling sorption phenomena involving the interactions of chemicals and particularly herbicides is very difficult because of the strong heterogeneity of the soil matrix. The present work presents the results of applying the most common models, i.e. Freundlich and Linear, as well as the newer concept of the Dual Reactive Domain model. The data obtained were validated using various statistical and chemometric methods.

The results suggest that applying the non-linear least-squares method to obtain isotherm parameters gave a much better description of the sorption phenomena than often obtained using linear transformations of the adsorption equations. The study also showed that appropriate weighting schemes should be included in any model calculations. To test the goodness-of-fit of the model to the experimental data both the correlation coefficient and the Residual Root Mean Square Error were obtained. The models were also compared using the Extra Sum of Squares Principle statistical test.
Utilisation of a Mesoporous Silicate Material for the Removal of Quaternary Ammonium Hydroxides (QAHs) from Aqueous Solution
Authors: Kelleher Brian P. , Doyle Aidan M. , Hodnett Benjamin K. , O'Dwyer Thomas F.
Published: November 2003

A cubic mesoporous silicate (CMS) was prepared, characterised and assessed as an adsorbent for quaternary ammonium hydroxides (QAHs) from aqueous solution. The adsorption process was studied as a function of molecular size and CMS pore volume. Sorption closely followed the Langmuir model. A comparison of the CMS pore volume and the volume of the sorbed molecules suggested that monolayer sorption occurred and that the number of molecules sorbed was a function of the size of the quaternary ammonium hydroxide molecule and the threshold area capable of being occupied by this molecule.
Modified Organosilica Adsorbents with Bactericidal Properties
Authors: Denisova T.I. , Shvetz D.I.
Published: November 2003

The method of mathematical planning of experiments has been used to determine the optimal conditions for the formation of a two-component organosilica with various compositions modified by metal ions (CuII, ZnII) sorbed from their water–ammonia solutions. Through this method, modified forms of silico-polymethylsiloxanes (SG-PMS) containing 1–30 mg/g CuII ion [SG-PMS(Cu)] and 3–40 mg/g ZnII ion [SG-PMS(Zn)] were synthesized and their adsorption/structural characteristics established. The sorptive capacity of the organosilica sorbents and their modified forms towards pathogenic microflora ( E. coli, S. aureus, P. aeruginosa), which depend on the concentration of the modified component, the pH of the medium and the sorptional composition, has been evaluated.

It was found that the sorption levels of microorganisms increased in the following sorbent-modified range: 30:70 wt% SG-PMS(Al) < 50:50 wt% SG-PMS(Zn) < 50:50 wt% SG-PMS(Cu) and attained values in the range of 81–98% for metal-containing forms depending on the pH of the medium and the nature of the microorganisms. Copper-containing forms of organosilica exhibited an inhibiting effect towards pathogenic microorganisms even at CuII ion-containing contents of only 1 mg/g.
Improved Pore-Size Analysis of Carbonaceous Adsorbents
Authors: Choma J. , Jaroniec M. , Kloske M.
Published: November 2003

An improvement was proposed for the pore-size analysis of active carbons based on low-temperature (77 K) nitrogen adsorption isotherms measured over a wide range of relative pressures (5 × 10−7–0.995). It was shown that the applicability of the Barrett, Joyner and Halenda (BJH) computational method based on the Kelvin equation could be extended significantly towards small mesopores and large micropores when a proper t-curve was used to represent the film thickness of nitrogen adsorbed on the carbon surface. It was proposed that the aforementioned t-curve be obtained from the nitrogen adsorption isotherm at 77 K on a macroporous carbon black by fitting its multilayer part to the calibrated t-curve for nitrogen adsorbed at 77 K on a macroporous silica. To date, the Harkins–Jura or Halsey t-curves have been used to describe the pressure-dependence of the film thickness. This appears to be inaccurate, especially in the range of low relative pressures. It was shown that this inaccuracy makes the pore-size analysis questionable. However, the t-curve proposed in this work gave the pore-size distribution functions for the carbons studied thereby reproducing the total pore volume and showing realistic behaviour in the range at the borderline between micropores and mesopores.
Advances in Orthodontics
Authors: Cunningham Susan J , Jones Steven P , Hodges Samantha J , Horrocks Elisabeth N , Hunt Nigel P , Moseley Howard C , Noar Joseph H
Published: November 2003

There has been tremendous progress in orthodontics since Edward Angle first popularised the fixed orthodontic appliance at the turn of the century. Recent years have seen an increased demand for orthodontic treatment from both adolescents and adults and, in addition, patient and clinician expectations of treatment outcomes continue to rise. A desire for more aesthetic materials has resulted in both smaller and ‘tooth-coloured’ appliances. Improvements in technology, often outside orthodontics, have also led to the development of new materials. The best example of this was the development of nickel titanium alloy by the NASA space programme, which was subsequently adapted for use in nickel titanium archwires. Other technological advances adopted for use in orthodontics include magnets, computerised imaging systems and distraction osteogenesis.

This review paper looks at some of the innovations in the fields of materials as well as in techniques and appliance systems.
An Audit on the Placement and Replacement of Restorations in a General Dental Practice
Authors: Frost Peter M
Published: November 2003

Objectives

To determine the reasons for placing and replacing restorations in a general dental practice amongst a group of patients.

Methods

This study used the method devised by Mjör and later modified by Burke and others. Instruction and data collection sheets were sent out to general dental practitioners (GDPs) for participation in a multicentre study. The GDPs were asked to record consecutively all restorations placed over a period of one month. The author is presenting his data collected over a period of six months using the same methodology. The author's results will be compared with a VDP study and the multicentre study.

Results

779 restorations were placed during the six months of the study. Three hundred and sixty-four (47%) were initial placements and 415 (53%) replacements. Primary fractured teeth totalled (16%) of the restorations. Other reasons for restoration placement were marginal fracture/degradation (31%), non-carious defects (13%) and both primary and secondary caries (9%). The proportion of glass-ionomer restorations increased with the age of the patient compared with amalgam and composites (chi-square: p<0.001), averaging 64% in age groups between 35 and 75 years, increasing to 88% in those patients over 75 years.

Conclusions

The principal reasons for placement and replacement of restorations in this study were repairs to tooth fractures. The proportion of amalgams and composites decreased with age while the proportion of glass ionomers increased.
Optimizing Television Program Schedules Using Choice Modeling
Authors: Danaher Peter J. , Mawhinney Donald F.
Published: November 2003

The authors examine the rescheduling of television programs to maximize the total ratings for one network across a week. The key idea is to design a choice experiment in which television programs are rescheduled and presented to respondents. Respondents read these program schedules (much like the regular TV Guide listings) and give their preferences, including not watching any of the listed programs. Because there are potentially billions of possible schedules, the authors give a procedure for designing a fractional factorial experiment that can accommodate both programs of varying length and constraints on eligible program times. The authors also develop a latent class multinomial logit model for modeling program preferences and present a validation of our experimental procedure and the model. They also present an empirical test of the procedure in which they use the model to predict ratings for all the possible program schedules, not just those constituting the choice sets. In this example, the optimum schedule increases the predicted total weekly ratings during prime time by 18% for a network. The projected increase in total weekly ratings is achieved without the network needing to purchase any new programs; all it needs to do is reschedule eight programs in its existing prime-time lineup.
Threats to the External Validity of Brand Extension Research
Authors: Klink Richard R. , Smith Daniel C.
Published: November 2003

The findings of prior research suggest that a brand's extendibility is constrained by the degree of perceived fit between the brand and extension product categories. However, there are many examples of brands that have been extended successfully into “perceptually distant” domains. Drawing on theories of consumer information processing and product adoption, the authors identify three background traits of prior work that may help explain the discrepancy between prior research and marketplace observation: (1) limited extension information, (2) failure to account for consumers' new product adoption tendencies (i.e., earlier versus later), and (3) single exposure to proposed extensions. In this study, the authors find that the effects of fit disappear when attribute information is added to extension stimuli and are applicable only for later product adopters. The authors also find that perceived fit increases with greater exposure to an extension. Beyond implications for brand extension research, this study underscores the need to recognize that certain research design factors related to external validity, which are often assumed irrelevant, can alter what is held to be true.
What We See Makes Us who We are: Priming Ethnic Self-Awareness and Advertising Response
Authors: Forehand Mark R. , Deshpandé Rohit
Published: November 2003

The authors propose that “ethnic self-awareness”—a temporary state during which a person is more sensitive to information related to his or her own ethnicity—moderates consumer response to targeted advertising. Ethnic self-awareness occurs when a person engages in a process of self-categorization and uses ethnic criteria as the basis for this categorization. The authors hypothesize that “ethnic primes”—visual or verbal cues that draw attention to ethnicity—direct self-categorization and increase ethnic self-awareness. To test these hypotheses, the authors conduct two experiments. Using 109 Asian and Caucasian participants, Experiment 1 assessed the impact of exposure to an Asian ethnic prime on ethnic self-awareness and on response to targeted television advertising. Exposure to an ethnic prime increased the rate at which participants spontaneously mentioned their ethnicity in self-descriptions (a measure of ethnic self-awareness) and caused participants to respond more favorably to same-ethnicity spokespeople and advertising that targeted their ethnicity. Experiment 2 tested the theory in a print advertising context and extended the design by manipulating the type of ethnic prime participants saw (Asian or Caucasian) and the market that the focal advertisement targeted (Asian or Caucasian). Experiment 2 replicated the findings of Experiment 1 when the focal advertisement targeted Asians, but not when it targeted Caucasians.
Modeling Hedonic Portfolio Products: A Joint Segmentation Analysis of Music Compact Disc Sales
Authors: Moe Wendy W. , Fader Peter S.
Published: November 2003

The authors present a framework that enables researchers to differentiate better among a wide array of hedonic products. Specifically, the authors define and discuss characteristics of hedonic portfolio products and offer a joint segmentation model that is appropriate for understanding the sales dynamics of this class of products. The model offered in this article can accommodate a large degree of product heterogeneity through product clusters and model covariates. The basic premise is that several generic consumer segments exist and remain fixed across all albums, and each album (or each cluster of similar albums) can be viewed as drawing different proportions from each of these underlying segments. The authors also allow explanatory variables to have a differential impact on both components of the model—that is, accelerating purchase rates within a consumer segment and changing the proportions drawn from each consumer segment by each product cluster—thereby expanding or contracting the potential market size. The authors apply this model to music compact disc sales for 20 different albums and discuss the different effects of radio airplay and holiday buying on sales for a sample in the music industry.
Strategic Management of Expectations: The Role of Disconfirmation Sensitivity and Perfectionism
Authors: Kopalle Praveen K. , Lehmann Donald R.
Published: November 2003

The authors suggest that people strategically manage—specifically, lower—their expectations to increase future satisfaction. Consumers who are more disconfirmation sensitive, that is, those who are more satisfied (dissatisfied) when a product performs better (worse) than expected, are hypothesized to have lower expectations. In contrast, the authors expect that consumers who are perfectionists will have higher expectations than those who are not. Results from a laboratory experiment and a field study are consistent with the hypotheses. Furthermore, the authors identify a possible third type of expectation (“as-if”) that serves as a basis for post-purchase evaluation and provide preliminary evidence that it differs from both will and should expectations.
The Differential Impact of Goal Congruency on Attitudes, Intentions, and the Transfer of Brand Equity
Authors: Martin Ingrid M. , Stewart David W.
Published: November 2003

Various theories suggest that the perceived similarity of objects facilitates the transfer of knowledge, affect, and intentions from one object to the other. However, there is disagreement as to the meaning of similarity and how it should be operationalized among these various theories, and no effort to relate these various measures to one another exists in the literature. In an empirical study, the authors examine the relationships among measures of product similarity in three different contexts: (1) goal-congruent products, (2) moderately goal-incongruent products, and (3) extremely goal-incongruent products. The results of exploratory factor analyses revealed that perceived similarity is a multidimensional construct and that the number and structure of these dimensions of similarity are different when products differ in their degrees of goal congruency. Structural equation analyses of the measures based on a second sample confirmed the structure obtained in the earlier exploratory analyses and demonstrated that brand attitudes and purchase intention exhibit different relationships to the underlying dimensions of similarity in the goal-congruent and goal-incongruent conditions, consistent with expectations based on the theory of goal-derived categorization. The authors discuss implications of these findings for theory and practice.
Do We Really Know how Consumers Evaluate Brand Extensions? Empirical Generalizations Based on Secondary Analysis of Eight Studies
Authors: Bottomley Paul A. , Holden Stephen J.S.
Published: November 2003

The authors investigate the empirical generalizability of Aaker and Keller's model of how consumers evaluate brand extensions. Various replications have reported different results. Using a comprehensive data set containing the data from the original study and seven replications conducted around the world, the authors undertake a secondary analysis to understand what generalizations emerge. The study has implications for the understanding of how brand extensions are evaluated and how empirical generalizations are made. For brand extensions, Aaker and Keller's model hypothesizes that evaluations of brand extensions are based on the quality of the original brand, the fit between the parent and extension categories, and the interaction of the two. The authors find support for this full model despite published results, including Aaker and Keller's own, that support only some of the hypotheses. The authors find evidence that the level of contribution of each of these components varies by brand and culture. With respect to empirical generalizations, the key implication is that it is premature to make firm conclusions about theory on the basis of only one study.
Mode of Infiltrative Growth of Colorectal Liver Metastases Is a Useful Predictor of Recurrence after Hepatic Resection
Authors: Yamaguchi Junzo , Komuta Kou , Matsuzaki Sumihiro , Okudaira Sadayuki , Fujioka Hikaru , Kanematsu Takashi
Published: November 2003

Many studies have been conducted to determine prognosis on the basis of the characteristics of metastatic liver tumor from colorectal cancer. The present study was carried out to determine whether the pathological mode of infiltrative growth (INF) of a metastatic liver nodule is useful in predicting recurrence in the remnant liver after hepatic resection. A total of 42 curative hepatic resections were performed for 37 patients with isolated liver metastases from colorectal cancer. Multivariate analysis (n = 42) showed that number, INF type, and size of liver metastases were statistically significant as independent risk factors. Of these, 28 resected liver metastases (smaller than 6 cm in size or containing fewer than 4 nodules) were classified pathologically into INF alpha or beta types (INF a b; n = 14) and gamma type (INFg; n = 14). Disease‐free survival at 5 years was 64% for patients with INF a b type, and 14% for those with the INF g type of liver metastases. Of these, recurrent disease of the liver after hepatic resection was found in 2 (14%) and 11 (79%) patients with INF a b and INF g types, respectively. From these observations, we concluded that pathological infiltrative growth of liver metastases is an informative predictor of disease‐free survival and especially of recurrence in the remnant liver.
Neoadjuvant Chemotherapy followed by Salvage Surgery: Effect on Survival of Patients with Primary Noncurative Gastric Cancer
Authors: Yano Masahiko , Shiozaki Hitoshi , Inoue Masatoshi , Tamura Shigeyuki , Doki Yuichiro , Yasuda Takushi , Fujiwara Yoshiyuki , Tsujinaka Toshimasa , Monden Morito
Published: November 2003

The prognosis for gastric cancer patients who undergo noncurative resection is extremely poor. This study evaluated the effects of neoadjuvant chemotherapy for primary noncurative gastric cancer. Thirty‐four patients with biopsy‐proven noncurative gastric cancer were treated with either of two neoadjuvant chemotherapies: FEMTXP (5‐fluorouracil, epirubicin, methotrexate, cisplatin) or THP‐FLPM (pirarubicin, 5‐fluorouracil, leucovorin, cisplatin, mitomycin C). Noncurability was determined by conventional staging procedures, staging laparoscopy, and exploratory laparotomy. After chemotherapy the resectability of the tumors was reassessed. Patients who were judged to be candidates for curative resection underwent salvage surgery. Of the final 33 patients, 8 (24.2%) showed a major response [0 complete response (CR), 8 partial response (PR)]. In three patients the second laparoscopy revealed disappearance of the peritoneal metastasis. Of the 33 patients, 14 (42.4%) underwent salvage surgery, including 8 curative resections (2 curability A, 6 curability B). Pathologic examinations revealed a grade 2 response in eight patients but no grade 3 response. Univariate analysis showed the following to be significant prognostic factors: histology type (differentiated type vs. undifferentiated type; p = 0.035), T4 as a noncurative factor (T4 vs. T3 or less; p = 0.025), clinical response (PR + no change vs. progressive disease; p = 0.002), and salvage surgery (resected vs. unresected; p = 0.001). Among these factors, salvage surgery was found to be the only independent prognostic factor by multivariate analysis, with a relative risk of 0.253 and a 95% confidence interval of 0.066 to 0.974. The treatment was well tolerated. Major toxicities of WHO grade 3 or more were leukopenia in 20 (60.6%), gastrointestinal toxicities in 5 (15.2%), renal toxicities in 2 (6.1%), and alopecia in 1 (3.0%). In conclusion, neoadjuvant chemotherapy is effective for primary noncurative gastric cancer when salvage surgery can be performed. A chemotherapy regimen with a higher complete response rate would improve the prognosis of this dismal disease even more.
Hepatic Resection Combined with Portal Vein or Hepatic Artery Reconstruction for Advanced Carcinoma of the Hilar Bile Duct and Gallbladder
Authors: Shimada Hiroshi , Endo Itaru , Sugita Mitsutaka , Masunari Hideki , Fujii Yoshiro , Tanaka Kuniya , Misuta Koichi , Sekido Hitoshi , Togo Shinji
Published: November 2003

Hepatectomy with vascular reconstruction for biliary malignancy remains controversial. This study aimed to clarify the indications for surgery. Patients with advanced hilar bile duct cancer (HBDC) (n = 26) and gallbladder cancer (GBC) involving the hepatoduodenal ligament (n = 13) who underwent hepatectomy were enrolled. They were divided into two groups on the basis of whether vascular reconstruction was performed (HBDC, 10 yes vs. 16 no; GBC, 5 yes vs. 8 no). Portal vein (PV) reconstruction was performed on the right branch in seven patients and on the left branch in two; hepatic artery (HA) reconstruction was done on the right branch in 11 patients and on the left branch in 1. Five patients with HBDC and one with GBC underwent both PV and HA reconstruction. Patency rates were 88.0% and 83.3% for PV and HA reconstructions, respectively. Vascular reconstruction‐related morbidity occurred in one patient with fatal liver failure owing to a portal thrombus and in two patients with multiple liver abscesses caused by arterial obstruction. Microsurgery eliminated reconstruction‐related morbidity. Mortality in vascular reconstruction cases was 13.3% (2/15), and in those without reconstruction it was 8.3% (2/24). Curability rates (R0 and R1+R2) were 50.0% and 56.0% for HBDC and 40.0% and 62.5% for GBC, respectively. The 3‐year survivals of HBDC patients were, respectively, 33% and 42%, and the 5‐year survivals were 18% and 25%, whereas for GBC the 1‐year survivals were 20% and 60% and the 2‐year survivals 0% and 25%. Two patients with vascular involvement who underwent PV with HA reconstruction survived more than 3 years. Hepatectomy with vascular reconstruction for selected HBDC patients offers low surgical risk and increased survival by curable resection, but it is not recommended for advanced GBC.
Quality of Life Improvement after Videothoracoscopic Splanchnicectomy in Chronic Pancreatitis Patients: Case Control Study
Authors: Makarewicz Wojciech , Stefaniak Tomasz , Kossakowska Marlena , Basiński Andrzej , Suchorzewski Marek , Stanek Aleksander , Gruca Zbigniew B.
Published: November 2003

The authors report on the effectiveness of videothoracoscopic splanchnicectomy (VSPL) as a method of pain treatment in patients with chronic pancreatitis (CP). A minimally invasive technique, VSPL is used in CP as an alternative method of pain treatment. The aim of the investigation was to evaluate by a prospective, semirandomized case‐control study the influence of VSPL on the quality of life and the level of pain suffered by patients with CP. The study groups consisted of 32 patients who underwent VSPL between March 2000 and January 2001 and a control group of 32 CP patients who received conservative treatment. The effect of the therapy on subjective pain measures and multiparametric quality of life was measured before VSPL and throughout the first year thereafter. In the follow‐up period there was a significant decrease in intensity of pain and an improvement in the quality of life of the patients—most significantly concerning emotional well‐being and functioning in everyday life. We conclude that the VSPL is a safe, effective, and minimally invasive procedure and recommend that it be used in such cases.
Prevalence of Ischemia in Diabetic Foot Infection
Authors: Khammash Muhammad R. , Obeidat Khaled A.
Published: November 2003

Foot infection is a common problem affecting diabetics. In addition to neuropathy, ischemia is a major factor contributing to the progress and morbidity of the disease. The aim of this study was to determine the prevalence of lower limb ischemia in patients with diabetic foot infection by prospectively measuring the ankle‐brachial pressure index (ABI). Over a 21‐month period 60 patients were treated in the general surgical ward of Princess Basma Teaching Hospital. Ischemia was present in 35 of the 60 patients (58.4%). Among them 27 had moderate ischemia (ABI 0.5–0.9) and were treated successfully before further vascular workup. The other 8 patients had severe ischemia (ABI < 0.5) and required below‐knee amputation because their feet were severely infected and not salvageable. This study confirmed the recommendation for early detection of lower limb ischemia in diabetics, especially those with foot infection, as it should improve the outcome of treatment. In addition to patient education and periodic foot examinations, estimating the ABI is an easy. reliable way to determine foot blood flow and to detect patients who require further vascular workup and treatment.
Relation of Cytokines to Vasodilation after Coronary Artery Bypass Grafting
Authors: Wei Minxin , Kuukasjärvi Pekka , Laurikka Jari , Kaukinen Seppo , Honkonen Eva‐Liisa , Metsänoja Riina , Tarkka Matti
Published: November 2003

Hemodynamic instability is frequent after coronary surgery. The present study tested the hypothesis that inflammation, as determined by circulating cytokine levels, may contribute to the difficulty of controlling arterial blood pressure after coronary artery bypass grafting. A group of 44 male patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass were studied. Plasma levels of tumor necrosis factor‐α, interleukin‐6 (IL‐6), IL‐8, and IL‐10 were measured before anesthesia induction, 5 minutes and 1 hour after reperfusion to the myocardium, and 2 and 18 hours after arriving in the intensive care unit (ICU). The 29 patients who did not need a vasopressor (norepinephrine) during their ICU stay were designated group I. They were compared to group II, which consisted of 15 patients who required a pressor agent in the ICU. Although no significant differences between groups were found regarding their hemodynamic variables, IL‐6 and IL‐8 levels were higher in the patients who used a pressor agent in the ICU. The norepinephrine dosage used in the ICU correlated with plasma IL‐8 levels 2 hours after arriving in the ICU (r = 0.56, p = 0.031). Circulating IL‐6 levels in group II were significantly higher than those in group I 2 hours after arriving in the ICU (126.5 ± 90.5 vs. 66.5 ± 48.2 pg/ml; p < 0.05). The mean IL‐8 levels were higher in group II at 5 minutes (34.9 ± 25.7 vs. 17.3 ± 11.3 pg/ml) and 1 hour (38.6 ± 30.5 vs. 22.4 ± 16.7 pg/ml) after reperfusion, and 2 hours (33.0 ± 21.6 vs. 22.8 ± 16.7 pg/ml) after arriving in the ICU (p = 0.036). Postoperative vasodilation was associated with increased circulating IL‐8 levels. Strategies that modulate cytokine responses may improve hemodynamic stability after coronary artery bypass grafting.
Prediction of Cardiac Risk prior to Elective Abdominal Aortic Surgery: Role of Multiple Gated Acquisition Scan
Authors: Karkos Christos D. , Thomson George J.L. , Hughes Robert , Joshi Miland , Baguneid Mohamed S. , Hill Jonathan C. , Mukhopadhyay Umasankar S.
Published: November 2003

Debate continues regarding the value of cardiac testing before major vascular surgery. Studies looking at whether a low radioisotope left ventricular ejection fraction (LVEF) could reliably predict postoperative cardiac events have produced conflicting results. Technetium‐99m multiple gated acquisition (MUGA) scanning was employed in 122 patients undergoing elective abdominal aortic aneurysm surgery to estimate the resting LVEF and to detect regional or global myocardial wall motion abnormalities (WMAs). Adverse cardiac outcomes were predicted using logistic regression analysis. Among this group of patients, 20 did not proceed to surgery for a variety of reasons, and 102 underwent surgical repair. More than half of the patients (55%) had a history of cardiac disease. The mean ± SD LVEF was 55.5% ± 11.1%. Altogether, 31 patients had WMAs, and 21 had both WMAs and an abnormal LVEF (≤ 50%). Altogether, 20 cardiac complications were encountered in 17 patients (17%). Logistic regression analysis identified four significant predictors of cardiac complications: history of cardiac disease [odds ratio (OR) 10.43; 95% confidence interval (CI) 1.3 and 80.5], the presence of WMAs (OR 10.1, CI 1.4 and 74.6), additional procedures (OR 12.1, CI 1.4 and 103.0), and reoperation during the postoperative period (OR 6.4, CI 1.4 and 30.4). This is the largest reported British series of cardiac testing using MUGA scans prior to abdominal aortic reconstruction. Only the presence of WMAs (not the resting LVEF) was useful for predicting postoperative cardiac events. A history of cardiac disease, additional procedures, and reoperation during the postoperative period also place a patient at high risk for cardiac complications. A normal LVEF is by no means reassuring that a patient is at low risk of suffering an adverse cardiac outcome.
Locally Advanced Breast Cancer inDeveloping Countries: The Place of Surgery
Authors: Apffelstaedt Justus P.
Published: November 2003

Most breast cancer patients in developing countries still
present with locally advanced breast cancer (LABC). Because surgery is the most
widely available treatment modality, we examine its place in the management of
LABC. Historically, single local treatment modalities have had disappointing
results, and multimodality therapy has become the norm for combatting LABC.
Combining surgery and radiotherapy will lead to superior local control rates.
Surgery should precede radiotherapy. Preoperative systemic treatment—with
the possible exception of cyclophosphamide, methotrexate, 5‐fluououracil (CMF)
chemotherapy—does not influence surgical complication rates. Hormonal
therapy is understudied and underutilized; its benefits become apparent only in
prolonged follow‐up. Sequencing of local and systemic treatments does not
influence oncologic outcome, but failure to respond to preoperative systemic
therapy may identify patients with a poor prognosis. With multimodality
management including hormonal therapy, chemotherapy, radiotherapy, and surgery,
local control rates of more than 80% and 5‐year survival rates of more than 50%
have become the norm.
Does Fibrin Glue Reduce Lymph Leakage (Pleural Effusion) after Extended Esophagectomy? Prospective Randomized Clinical Trial
Authors: Tachibana Mitsuo , Kinugasa Shoichi , Yoshimura Hiroshi , Dhar Dipok Kumar , Ueda Shuhei , Fujii Toshiyuki , Kohno Hitoshi , Nagasue Naofumi
Published: November 2003

Fibrin glue has been shown to be effective in improving postoperative chylothorax following various thoracic procedures and in reducing lymphorrhea after axillary dissection. It is unknown, however, whether fibrin glue is effective in reducing lymph leakage (pleural effusion) after esophagectomy. A series of 43 consecutive patients with thoracic esophageal cancer who underwent extended esophagectomy were prospectively randomized to two groups: group A (n = 21), in whom 3 ml of fibrin glue was applied to the dissected mediastinum; and group B (n = 22), in whom fibrin glue was not applied. The time of drain removal and the volume of the thoracic drainage were compared. All data were expressed as the mean ± standard deviation. There were no significant differences in the clinicopathologic characteristics between the two groups. None of the patients developed chylothorax or died during their hospital stay. The daily volume from the thoracic drain (457 ± 273 ml) was significantly (p < 0.05) larger on postoperative day (POD) 1 in group A than in group B (298 ± 158 ml) and tended to be larger (p < 0.10) on PODs 4 and 6 in group A than in group B. The cumulative drainage volume was significantly (p < 0.05) larger on PODs 4 to 6 and POD 9, and it tended to be larger (p < 0.10) on PODs 1, 3, 7, 8, 10, and 11 in group A than in group B, suggesting that the cumulative drainage volume in group A was consistently larger than that in group B. The cumulative numbers of patients with a drain remaining in place were not significantly different for the two groups (p = 0.4683). Three patients in group A, however, had prolonged insertion (> 20 days) of the chest tube. There were no significant differences in the incidence of postoperative chest‐related complications. No patients in group A developed viral infectious disease during the long‐term follow‐up. Application of fibrin glue to the dissected mediastinum seems to induce postoperative lymph leakage and thus be responsible for prolonged chest tube insertion in some patients. Hence the use of fibrin glue cannot be recommended for reducing lymph leakage after esophagectomy.
Expression of Transforming Growth Factor Betas and Their Signaling Receptors in Stone‐containing Intrahepatic Bile Ducts and Cholangiocarcinoma
Authors: Lee King‐Teh , Liu Tsan‐Shium
Published: November 2003

Transforming growth factor betas (TGF‐βs) are multifunctional polypeptides that either inhibit or stimulate cell proliferation. They mediate their functions through their signaling receptors. Clinically, hepatolithiasis has been regarded as a risk factor for cholangiocarcinoma. The aim of this study was to examine the expression of TGF‐βs and their receptors in stone‐containing intrahepatic bile ducts (IHD) and cholangiocarcinoma and try to predict whether hepatolithiasis has a predisposition to development of cholangiocarcinoma. Twenty‐eight surgically resected specimens of stone‐containing IHD and 15 specimens of cholangiocarcinoma were subjects for this study. Immunohistochemical analysis was done on three TGF‐βs and their signaling receptors to check their expression in non‐neoplastic and neoplastic bile ducts. No immunoreactivity of TGF‐β1 was found in any specimens. The overexpression of TGF‐β2 and TGF‐β3 was found in both hepatolithiasis (93%–100%) and cholangiocarcinoma (80%) at levels significantly higher than those of normal controls (10%–20%) (p < 0.001). The immunoreactivity of type I receptor (TβRI) and type II receptor (TβRII) also showed increased expression in stone‐containing IHD, whereas TβRII was absent in cholangiocarcinoma. We conclude that the overexpression of TGF‐β2 and TGF‐β3 and the absence of TβRII in cholangiocarcinoma could lead to enhanced tumor cell proliferation. At the same time, the overexpression of TGF‐βs and their receptors in stone‐containing IHD could suggest a close relationship between hepatolithiasis and cholangiocarcinoma.
Obstructive Jaundice Alters Proliferating Cell Nuclear Antigen Expression in Rat Small Intestine
Authors: Sheen‐Chen Shyr‐Ming , Ho Hsin‐Tsung , Chen Wei‐Jen , Eng Hock‐Liew
Published: November 2003

Translocation of bacteria and endotoxin has long been documented in obstructive jaundice, and altered intestinal barrier function is considered to be one of the important mechanisms for this phenomenon. Proliferating cell nuclear antigen (PCNA), also known as cyclin, is an auxiliary protein of DNA polymerase‐δ, and the level of synthesis correlates directly with rates of cellular proliferation and DNA synthesis. This study was designed with the aim of evaluating the effect of obstructive jaundice on PCNA expression in small bowel epithelium. Male Sprague‐Dawley rats were randomized to four groups. Group A (n = 10, control group) underwent a sham operation. Group B (n = 9, obstructive jaundice group for 1 week) underwent common bile duct ligation. Group C (n = 8, obstructive jaundice group for 2 weeks) underwent common bile duct ligation. Group D (n = 8, obstructive jaundice group for 2 weeks) underwent common bile duct ligation with oral glutamine intake. After periods of 7 days and 2 weeks, segments of small bowel were harvested from groups A & B and groups C & D, respectively. Nuclear immunohistochemical expression of PCNA in small bowel was evaluated. The PCNA‐labeling index [(PCNA‐positive cells/500 cells) × 100] was quantified. Comparisons among the four groups were performed. The PCNA‐labeling index in small bowel of group B was significantly higher than that of group A (29.0% vs 21.2%, p = 0.001). After 2 weeks of common bile duct ligation, the PCNA‐labeling index in small bowel of group C was significantly lower than that of group A (19.4% vs 21.2%, p = 0.045). With oral glutamine intake daily, the PCNA‐labeling index in small bowel of Group D was restored and was significantly higher than that of group A (24.5% vs 21.2%, p = 0.002). Obstructive jaundice for 1 week upgraded PCNA expression in rat small intestine. PCNA expression in rat small intestine later became depressed after obstructive jaundice for 2 weeks. Oral glutamine intake daily could effectively restore the PCNA expression in small bowel of rats subjected to obstructive jaundice for 2 weeks.
Experimental Evidence for Mutagenic Potential of Duodenogastric Juice on Barrett’s Esophagus
Authors: Theisen Joerg , Peters Jeffrey H. , Stein Hubert J.
Published: November 2003

The aim of this article is to review the current experimental knowledge of mutagenesis in Barrett’s esophagus (BE) with special emphasis on the effect of bile salts and acid. Human evidence of direct mutagenicity is rare. Only the correlation of increased quantities and a change in the quality of bile salts with the complications of duodenogastric reflux such as BE and esophageal adenocarcinoma as an indirect marker of mutagenicity has been shown in several studies. Further evidence comes fromp53studies demonstrating an increased number of mutatedp53genes in patients with BE, esophageal adenocarcinoma, or both. Most animal and cellular experiments are carried out in a neutral pH environment, not reflecting the true nature of a reflux episode. The few studies using moderate low acid reflux conditions in combination with bile salts demonstrated a combined effect on mutagenicity. Our current knowledge of bile salt mutagenicity is predominantly based on experiments with hepatocytes and colon cancer cell lines. Future studies must be aimed at esophageal cell lines, cultured Barrett’s tissue, and esophageal adenocarcinoma cell lines.
Fluorodeoxyglucose‐Positron Emission Tomography in Adenocarcinomas of the Distal Esophagus and Cardia
Authors: Ott Katja , Weber Wolfgang A. , Fink Ulrich , Helmberger Hermann , Becker Karen , Stein Hubert J. , Müller James , Schwaiger Markus , Siewert Jörg Rüdiger
Published: November 2003

Adenocarcinomas of the esophagogastric junction (AEG) are now recognized as a separate tumor entity with increasing incidence. The aim of the present study was to evaluate whether positron emission tomography (PET) using the glucose analog F‐18‐fluorodeoxyglucose (FDG) can be used for metabolic characterization of this tumor type. Fifty‐two patients with histologically proven, locally advanced AEG (distal esophagus, type I: n = 31; cardia, type II: n = 21) were studied by FDG‐PET. None of the tumors had been previously treated. Findings of endoscopy (growth type), endoluminal ultrasound (uT, uN), computed tomography (cN, cranio‐caudal extent, tumor thickness), histological evaluation (Lauren classification, tumor grade), anatomical classification, and survival were correlated with the results of FDG‐PET. There was no correlation between FDG uptake and clinical stage, grade, Lauren classification, or survival. All AEG I tumors were visualized by FDG‐PET with high contrast, whereas FDG uptake by five AEG II tumors (24%) did not differ from background activity. In a quantitative analysis, mean FDG uptake of AEG I tumors was 1.6 times higher than that of AEG II tumors (p = 0.0005). PET can be used to visualize type I adenocarcinomas of the esophagogastric junction (AEG I). In AEG II tumors, however, the use of FDG‐PET appears to be limited. The significantly higher FDG uptake of AEG I tumors compared to AEG II tumors suggests that these two tumor types differ in glucose utilization. This finding strengthens the hypothesis that AEG I and AEG II are two different tumor entities.