bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Low Molecular Weight Heparin on Survival in Patients With Advanced Malignancy
Authors: Klerk Clara P.W. , Smorenburg Susanne M. , Otten Hans-Martin , Lensing Anthonie W.A. , Prins Martin H. , Piovella Franco , Prandoni Paolo , Bos Monique M.E.M. , Richel Dick J. , van Tienhoven Geertjan , Büller Harry R.
Published: February 2005

Purpose

Studies in cancer patients with venous thromboembolism suggested that low molecular weight heparin may prolong survival. In a double-blind study, we evaluated the effect of low molecular weight heparin on survival in patients with advanced malignancy without venous thromboembolism.

Methods

Patients with metastasized or locally advanced solid tumors were randomly assigned to receive a 6-week course of subcutaneous nadroparin or placebo. The primary efficacy analysis was based on time from random assignment to death. The primary safety outcome was major bleeding.

Results

In total, 148 patients were allocated to nadroparin and 154 patients were allocated to placebo. Mean follow-up was 1 year. In the intention-to-treat analysis the overall hazard ratio of mortality was 0.75 (95% CI, 0.59 to 0.96) with a median survival of 8.0 months in the nadroparin recipients versus 6.6 months in the placebo group. After adjustment for potential confounders, the treatment effect remained statistically significant. Major bleeding occurred in five (3%) of nadroparin-treated patients and in one (1%) of the placebo recipients (P = .12). In the a priori specified subgroup of patients with a life expectancy of 6 months or more at enrollment, the hazard ratio was 0.64 (95% CI, 0.45 to 0.90) with a median survival of 15.4 and 9.4 months, respectively. For patients with a shorter life expectancy, the hazard ratio was 0.88 (95% CI, 0.62 to 1.25).

Conclusion

A brief course of subcutaneous low molecular weight heparin favorably influences the survival in patients with advanced malignancy and deserves additional clinical evaluation.
Clinically Meaningful Improvement in Symptoms and Quality of Life for Patients With Non-Small-Cell Lung Cancer Receiving Gefitinib in a Randomized Controlled Trial
Authors: Cella David , Herbst Roy S. , Lynch Thomas J. , Prager Diane , Belani Chandra P. , Schiller Joan H. , Heyes Anne , Ochs Judith S. , Wolf Michael K. , Kay Andrea C. , Kris Mark G. , Natale Ronald B.
Published: February 2005

Purpose

Evaluation of disease-related symptom improvement rate by the Lung Cancer Subscale (LCS) of the Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire was a coprimary end point of the pivotal phase II trial of gefitinib (Iressa; AstraZeneca, Wilmington, DE) conducted in the United States. This report includes the results of analyses exploring the relationship between weekly LCS scores and radiographic response and survival, as well as detailed protocol-specified analysis of symptom and quality-of-life data.

Patients and Methods

In this trial, 216 symptomatic patients with advanced non-small-cell lung cancer (NSCLC) who had at least two prior chemotherapy regimens received gefitinib 250 or 500 mg/d. Disease-related symptoms were assessed weekly and quality of life was assessed monthly by LCS and FACT-L, respectively.

Results

Symptom improvement was rapid and correlated with tumor response and survival. At the recommended gefitinib dose of 250 mg/d, median overall survival times were 13.6 and 4.6 months for patients with and without symptom improvement, respectively, and 9.7 months for patients with symptom improvement without tumor response. Among patients with stable disease or disease progression, those with symptom improvement had significantly better overall survival than those without improvement. At 250 mg/d, 30% of patients showed a quality-of-life improvement that was correlated with tumor response.

Conclusion

This triadic analysis of response, survival, and symptom data supports the hypothesis that tumor response and symptom response are related and that each predicts survival. Among these NSCLC patients treated with gefitinib, symptom improvement was complementary to and, for most patients, preceded evidence of radiographic regression.
Neonatal Lethal Osteochondrodysplasia with Low Serum Levels of Alkaline Phosphatase and Osteocalcin
Authors: Wyckoff Myra H. , El-Turk Chirine , Laptook Abbot , Timmons Charles , Gannon Francis H. , Zhang Xiafang , Mumm Steven , Whyte Michael P.
Published: February 2005

Neonatal lethal skeletal dysplasias are rare and typically involve thoracic malformations and severe limb shortening. We report on a newborn boy manifesting an osteochondrodysplasia associated with fatal respiratory insufficiency who had normal lung volumes and extremity lengths. His disorder featured aberrant skeletal patterning and defective ossification including a severely osteopenic skull, apparent absence of clavicles, and clefting of the mandible and vertebrae. Serum alkaline phosphatase and osteocalcin levels were markedly low. Biochemical studies suggested parathyroid insufficiency probably from critical illness. Histopathology at autopsy excluded impaired mineralization of skeletal matrix, but endochondral bone formation appeared disorganized with growth plate clustering of chondrocytes in hypertrophic zones and in zones of provisional calcification. Parathyroid glands were not found. Despite features of two distinctive heritable entities, hypophosphatasia and cleidocranial dysplasia, the cumulative findings did not match either condition, and no mutations were found in either the tissue nonspecific ALP isoenzyme or core-binding factor genes, respectively, or in the genes encoding osteocalcin or the osteoblast transcription factor osterix. This patient could represent the extreme of cleidocranial dysplasia (a disorder not always associated with structural mutation in core-binding factor A1), but more likely he defines a unique osteochondrodysplasia disrupting both intramembranous and endochondral bone formation.
Differential Role of Progesterone Receptor Isoforms in the Transcriptional Regulation of Human Gonadotropin-Releasing Hormone I (GnRH I) Receptor, GnRH I, and GnRH II
Authors: An Beum-Soo , Choi Jung-Hye , Choi Kyung-Chul , Leung Peter C. K.
Published: February 2005

Hypothalamic GnRH is a decapeptide that plays a pivotal role in mammalian reproduction by stimulating the synthesis and secretion of gonadotropins via binding to the GnRH receptor on the pituitary gonadotropins. It is hypothesized that sex steroids may regulate GnRH I (a classical form of GnRH), GnRH II (a second form of GnRH), and GnRH I receptor (GnRHRI) at the transcriptional level in target tissues. Thus, in the present study a role for progesterone (P4) in the regulation of GnRH I, GnRH II, and GnRHRI was investigated using a human neuronal medulloblastoma cell line (TE671) as an in vitro model. The cells were transfected with human GnRHRI promoter-luciferase constructs, and promoter activities were analyzed after P4 treatment by luciferase and β-galactosidase assay. The mRNA levels of GnRH I and GnRH II were analyzed by RT-PCR. Treatment of TE671 cells with P4 resulted in a decrease in GnRHRI promoter activity compared with the control level in a dose- and time-dependent manner. Cotreatment of these cells with RU486, an antagonist of P4, reversed P4-induced inhibition of GnRHRI promoter activity, suggesting that the P4 effect is mediated by P4 receptor (PR). In the cells transfected with a full-length of PR A- or PR B-expressing vector, overexpression of PR A increased the sensitivity toward P4 in an inhibition of GnRHRI promoter, whereas PR B increased transcriptional activity of GnRHRI promoter in the presence of P4. However, PR B itself did not act as a transcriptional activator of GnRHRI promoter. Because TE671 cells have been recently demonstrated to express and synthesize two forms of GnRHs, we also investigated the regulation of GnRH mRNAs by P4. In the present study, P4 increased GnRH I mRNA levels in a time- and dose-dependent manner. This stimulatory effect of P4 in the regulation of GnRH I mRNAs was significantly attenuated by RU486, whereas no significant difference in the expression level of GnRH II was observed with P4 or RU496. Interestingly, although the expression level of PR B was low compared with that of PR A, P4 action on the GnRH I gene was mediated by PR B. In conclusion, these results indicate that P4 is a potent regulator of GnRHRI at the transcriptional level as well as GnRH I mRNA. This distinct effect of P4 on the GnRH system may be derived from different pathways through PR A or PR B.
Detection of Monoclonality of the Immunoglobulin Heavy Chain Gene in Thyroid Malignant Lymphoma by Vectorette Polymerase Chain Reaction
Authors: Takano Toru , Miyauchi Akira , Matsuzuka Fumio , Yoshida Hiroshi , Notomi Tsugunori , Kuma Kanji , Amino Nobuyuki
Published: February 2005

Distinguishing between thyroid malignant lymphoma and lymphocytic thyroiditis (Hashimoto’s thyroiditis) is quite difficult and problematic. B cell lymphomas display clonal Ig heavy-chain (IgH) gene rearrangement, and Southern blot hybridization (SBH) is often used for detection of the monoclonality of the IgH gene. However, SBH is often problematic because it requires a large volume of samples. We examined the efficiency in detecting the monoclonality of IgH gene in thyroid malignant lymphomas by vectorette PCR, which we started with only 200 ng of genomic DNA. Monoclonality was detected in 36 of 47 (76.6%) malignant lymphomas, whereas it was not detected in 10 samples of tissue of Hashimoto’s thyroiditis. The sensitivity was almost the same as that with SBH in which monoclonality was detected in 33 of 45 (73.3%) malignant lymphomas. These results suggest that vectorette PCR may be a substitute for SBH, and because it requires only a small volume of samples, it may be used in the analysis of aspiration biopsies.
Relationship of Estradiol and Inhibin to the Follicle-Stimulating Hormone Variability in Hypergonadotropic Hypogonadism or Premature Ovarian Failure
Authors: Welt Corrine K. , Hall Janet E. , Adams Judith M. , Taylor Ann E.
Published: February 2005

Recent studies have demonstrated the presence of ovarian follicular development in up to 78% of women with premature ovarian failure (POF). The purpose of this study was to examine the control of FSH by estradiol and inhibin secretion from these follicles. Weekly blood samples were collected in conjunction with assessment of ovarian follicle development by ultrasound for at least 12 wk in 49 subjects with POF. Results were compared with those of 44 normal cycling women. Ovulatory cycles occurred in 24 subjects (49%) with POF. These ovulatory cycles were characterized by higher FSH and lower inhibin B and inhibin A levels, whereas estradiol levels were higher compared with those in normal women. Follicles developed in the absence of ovulation in 18 women (37%) with POF, whereas the ovaries were inactive in seven women (14%). FSH levels were lower in POF women with ovulatory or anovulatory follicle development compared with levels in women with inactive ovaries. These findings demonstrate that ovulatory cycles in women with POF are characterized by a persistent elevation in FSH compared with levels in normal cycling women. The association of increased FSH with lower levels of inhibin B and inhibin A, but higher estradiol levels provides additional evidence for an important physiological role of the inhibins in the negative feedback control of FSH. These data also demonstrate the variability in FSH levels as a function of underlying follicular development in women with POF.
Human Lymphocyte-Synthesized Melatonin Is Involved in the Regulation of the Interleukin-2/Interleukin-2 Receptor System
Authors: Carrillo-Vico Antonio , Lardone Patricia J. , Fernández-Santos José M. , Martín-Lacave Inés , Calvo Juan R. , Karasek Michal , Guerrero Juan M.
Published: February 2005

Since melatonin was first isolated in 1958 up to the last few years, this substance was considered a hormone exclusive to the pineal gland. Although melatonin has lately been identified in a large number of extrapineal sites, its potential biological actions have not yet been studied. This paper shows that human lymphocyte-synthesized melatonin plays a crucial role modulating IL-2/IL-2 receptor system because when blocking melatonin biosynthesis by the tryptophan hydroxylase inhibitor, parachlorophenylalanine, both IL-2 and IL-2 receptor levels fell, restoring them by adding exogenous melatonin. Moreover, we demonstrated that this endogenous melatonin interfered with the exogenous melatonin effect on IL-2 production. Melatonin exerted these effects by a receptor-mediated action mechanism because both IL-2 and IL-2 receptor expressions significantly decreased when lymphocytes were incubated in the presence of the specific membrane and/or nuclear melatonin receptor antagonists, luzindole, and/or CGP 55644, respectively. Finally, we made the real significance of the membrane melatonin receptors in this process clear, so prostaglandin E2-induced inhibition on IL-2 production increased when we blocked the membrane receptors using luzindole. In conclusion, these data show that endogenous melatonin is an essential part for an accurate response of human lymphocytes through the modulation of IL-2/IL-2 receptor system.
Body Fat and Vitamin D Status in Black Versus White Women
Authors: Looker Anne C.
Published: February 2005

Obesity has been linked to lower serum 25-hydroxyvitamin D [25(OH)D] values, but whether this relationship plays a role in the poorer vitamin D status observed in blacks vs. whites is not clear. This study examines the relationship between serum 25(OH)D and percent body fat (%BF) by race in 6042 women (3567 non-Hispanic whites and 2475 non-Hispanic blacks), aged 12+ yr, from the third National Health and Nutrition Examination Survey (NHANES III, 1988–1994). Serum 25(OH)D values were measured with an RIA kit (DiaSorin), and %BF was calculated from bioelectrical impedance analysis. Adjusting for %BF only slightly reduced differences in mean serum 25(OH)D by race. The negative relationship between serum 25(OH)D and %BF was noticeably stronger in whites than in blacks of the same age. Within race, the relationship was stronger in younger than older individuals. Adjusting for confounders reduced, but did not remove, these differences in relationship strength. In conclusion, the serum 25(OH)D-%BF relationship in women varies both by race (stronger in whites than blacks) and age (stronger in younger than older persons). This complex relationship may explain why differences in obesity do not appear to play a major role in explaining variation in serum 25(OH)D by race.
Artefacts in the mechanical characterization of porcine articular cartilage due to freezing
Authors: Willett T L , Whiteside R , Wild P M , Wyss U P , Anastassiades T
Published: February 2005

Many experimental protocols for investigating articular cartilage mechanics have involved the use of a freeze-thaw cycle for storage or tissue manipulation. It was hypothesized that mechanical properties are altered due to freeze-thaw cycling. The aim of this study, therefore, was to examine the possibility of protocol-induced artefacts in the mechanical properties of porcine articular cartilage specimens related specifically to freeze-thaw events. Twenty-eight osteochondral specimens [14 from the femoral condyles (FCs) and 14 from the patella-femoral (PF) groove] were tested in confined compression before and after being frozen at -20°C for 7 days. The fluid-independent and fluid-dependent mechanical properties (aggregate modulus of the solid phase and the half-life of stress relaxation respectively) were determined and compared. The aggregate modulus decreased by 13.5 per cent and 20.1 per cent for the PF and FC regions respectively ( p = 0.002) and the half-life of the stress relaxation at 10 per cent strain decreased by 6.4 per cent and 12.6 per cent for the PF and FC specimens respectively ( p = 0.0341). In conclusion, it has been shown that the protocol used, which involved freezing to -20°C and thawing after 7 days, caused artefacts in the mechanical properties of porcine osteochondral specimens. It is suggested that protocols requiring freezing must be critically reviewed to eliminate such artefacts.
A simple way to model wires used in ring fixators: Analysis of the wire stiffness effect on overall fixator stiffness
Authors: Nikonovas A , Harrison A J L
Published: February 2005

The Ilizarov fixator has become widely used in the treatment of complex trauma and deformity correction in the United Kingdom over the last few decades. As such, it has been widely researched. Within this fixator, the characteristic fine wires are the weakest and most flexible component. The wires allow interfragmentary micromotion, which is believed to be beneficial to bone healing. In this paper, a novel and simple numerical model of the stiffness and deflection of the wires when the fixator is subject to axial and torsional loading is presented. A range of wire lengths and pretensions are analysed, and the results compared to the findings of other researchers, with generally good agreement. This indicates that fixator stiffness can be determined simply and without recourse to sophisticated finite element analyses or extensive physical testing. In addition, the model is used to predict the contribution of the wires to the overall stiffness of the fixator.
Compression-induced damage in a muscle cell model in vitro
Authors: Wang Yak-Nam , Bouten C V C , Lee D A , Bader D L
Published: February 2005

Soft tissue breakdown can be initiated at the muscle layer associated with bony prominences, leading to the development of pressure ulcers. Both the magnitude and duration of pressure are important factors in this breakdown process. The present study utilizes a physical model, incorporating C2C12 mouse myoblasts in a homogeneous agarose gel, to examine the damaging effects of prolonged applied pressure. Identical cylindrical cores cut from the agarose/cell suspension were subjected to two separate compressive strains, of 10 and 20 per cent. The strain was applied for time periods ranging from 0.5 to 12 hours, using a specially designed loading apparatus. After each compression period, sections taken from the central horizontal plane of the individual constructs were stained using either haematoxylin and eosin or with the fluorescent probes, Calcein AM and ethidium homodimer-1, and assessed for cell damage. It was found that constructs subjected to the higher strain values demonstrated significantly higher values of non-viable cells for equivalent time points compared to the unstrained constructs. Further analysis on sections using the DNA nick-translation method suggested that this increase was primarily due to apoptosis. These findings imply a relationship between the duration of applied compression and damage to muscle cells seeded in the gel, which was particularly apparent at the strain level of 20 per cent, equivalent to a clinically relevant pressure of 32 mmHg (4.3 kPa). Such an approach might be useful in establishing damage threshold levels at a cellular level.
Interpretation of alpha-fetoprotein concentrations in cerebrospinal fluid of infants
Authors: Coakley J , Kellie SJ , Nath C , Munas A , Cooke-Yarborough C
Published: February 2005

Background: There are no published reference intervals for concentrations of alpha-fetoprotein (AFP) in the cerebrospinal fluid (CSF) of normal infants. The presence of abnormal concentrations of AFP in plasma or CSF may indicate the presence of a teratoma or a germ cell tumour with yolk sac elements. We measured CSF AFP in infants who did not have malignancy in order to determine its reference intervals.

Methods: AFP was measured in the CSF and/or plasma in 128 infants. Of these, 91 infants had CSF AFP measurements, 94 infants had plasma AFP measurements and in 60 infants AFP concentrations were determined in paired CSF and plasma samples. The patients ranged in age from 1 to 110 days. Both CSF and plasma AFP concentrations were measured by a microparticle enzyme immunoassay using an AxSYM analyser.

Results: Using ages corrected for prematurity, the median CSF AFP concentration for babies -69 to 31 days old was 61 kIU/L (5th-95th centile: 2-889 kIU/L), while the median CSF AFP concentration for infants 32 to 110 days was 1.2 kIU/L (5th-95th centile: 0.1-12.5 kIU/L). By age 6 weeks, the concentrations were close to those found in adult plasma and all CSF AFP concentrations from infants with a corrected age over 2 months were <3 kIU/L.

Conclusion: We have defined reference intervals for CSF AFP concentrations in infants. These results may assist in the diagnosis of CNS tumours, particularly congenital CNS tumours containing yolk sac elements.
Carbonyl stress in chronic renal failure: the effect of haemodialysis
Authors: Dursun Evrim , Dursun Belda , Süleymanlar Gültekin , Ozben Tomris
Published: February 2005

Oxidative stress has been defined as a loss of balance between free radical production and the antioxidant systems. There have been many reports of increased production of oxidants and decreased levels of antioxidants in chronic renal failure (CRF) patients. An increase in oxidative stress may contribute to the development of oxidative protein damage in CRF. Our aim was to reveal oxidative modifications of plasma proteins by measuring 2,4-dinitrophenylhydrazine reactive carbonyl derivates (PCO), protein thiol (P-SH) and reduced glutathione (GSH) in predialytic uraemic and haemodialysed (HD) patients before and after dialysis. We included 20 predialytic uraemic patients, 20 HD patients and 20 healthy volunteers in our study. PCO concentration in predialytic uraemic patients increased compared with the concentration of the control group and this increase was more profound in HD patients. P-SH concentrations were significantly decreased in haemodialytic patients compared with those of controls. GSH level was higher in HD patients (both before and after dialysis). Increased PCO and decreased P-SH concentrations in all patient groups in comparison to the control subjects indicate increased protein oxidation. Our data in ESRD patients propose plasma protein carbonyl derivates and thiol concentrations as novel specific markers for oxidative protein damage.
Japanese standard reference material JDS Lot 2 for haemoglobin A1c. II: Present state of standardization of haemoglobin A1c in Japan using the new reference material in routine clinical assays
Authors: Tominaga Makoto , Makino Hideichi , Yoshino Gen , Kuwa Katsuhiko , Takei Izumi , Aono Yukuko , Hoshino Tadao , Umemoto Masao , Shimatsu Akira , Sanke Tokio , Kuwashima Masamichi , Taminato Tomohiko , Ono Junko
Published: February 2005

Background: In 2001, the Committee on Standardization of Laboratory Testing Related to Diabetes Mellitus of the Japan Diabetes Society (JDS) prepared and certified a new reference material for haemoglobin A1c (HbA1c), Lot 2. The standardization programme for HbA1c measurement in Japan is currently based on Lot 2, although some laboratories still use the previous material (Lot 1). The values assigned to Lot 2 were based on the consensus values for Lot 1 and should give the same results. Therefore, there should be no difference in the measured values no matter which calibrators are used. The Committee conducted a domestic survey in order to confirm this relationship.

Method: In November 2002, four samples for HbA1c assay were sent to 795 laboratories as part of a national survey in Japan. Assays were performed using the laboratories' routine clinical methods. The coefficients of variation (CVs) of the reported values from all laboratories for the samples were calculated in order to determine the current level of standardization in Japan.

Results: The overall CVs in the measured values for the four samples ranged from 2.7% to 4.0%. Values from laboratories using calibrators based on Lots 1 and 2 were similar.

Conclusion: The present state of standardization for the routine measurement of HbA1c in Japan, as indicated by the 2002 survey, is excellent. This should aid in the eventual conversion of Lot 2 to IFCC-based values from the results of the 2002 national HbA1c survey.
Plasma aluminium: a redundant test for patients on dialysis?
Authors: Gault PM , Allen KR , Newton KE
Published: February 2005

Background: Aluminium toxicity as a cause of dementia, osteodystrophy and anaemia in patients receiving renal dialysis was first described in the 1970s and led to the regular monitoring of aluminium in plasma and dialysate water. However, aluminium phosphate binders have now been replaced by calcium-based binders or sevelamer and reverse osmosis (RO) water is used in the preparation of dialysate fluid. This has reduced the exposure of dialysis patients to aluminium and it is therefore opportune to review aluminium monitoring in patients undergoing regular renal dialysis.

Methods: Plasma and water aluminium results were audited over the period January 2000-January 2004, with results obtained from nine renal dialysis units in the UK. Patients with a plasma aluminium concentration in the toxic range (>3.7 μmol/L) were followed up by contacting the relevant consultant.

Results: Plasma aluminium results were collected on 1626 patients over the fouryear period (mean = 0.47 μmol/L, median = 0.3 μmol/L, range 0.07-30.26 μmol/L, n = 5918). Forty-six patients had an aluminium concentration >3.7 μmol/L and nine were not retested. Only three patients had a repeat aluminium concentration >2.2 μmol/L, one being a result of desferrioxamine treatment, with no further clinical information available on the other two. All renal units are using RO water to prepare dialysate and aluminium-based phosphate binders are no longer prescribed. Only one of 212 RO water aluminium concentrations measured was >10 μg/L. Patients with clinical symptoms of overt aluminium toxicity were not identified in this population.

Conclusion: The role of aluminium monitoring in long-term renal dialysis patients needs re-evaluation. Regular monitoring of plasma aluminium may not be required, but should be considered in any patient showing signs or symptoms of aluminium toxicity or exposed to a contaminated water supply. It is more important that RO water supplies are maintained and monitored. Environmental aluminium as a source of sample contamination should be considered and eliminated during blood collection and sample processing.
Troponin reporting in Australia in 2003
Authors: Davey Richard X
Published: February 2005

Background and method: This study uses a cross-sectional survey by questionnaire of Australia's pathology laboratories to describe how they report chemical markers for myocardial necrosis.

Results: The questionnaire was sent to 364 laboratories; 346 (95%) responded. Reporting data were obtained for 222 instruments used to analyse markers of myocardial necrosis, some 81% of all those in Australia. All laboratories use a troponin measurement. Reports from 132 analysers (59% of total) provide one cut-off point for the diagnosis of myocardial necrosis and 90 (41%) two cut-off points. The chosen cut-off points vary. The upper limit of 'healthy' is cited, alone, in 40 reports (18%); at this level, in 2002 no analysers predictably met required precision standards. Only 50% of all reports carry some explanatory comment; only 16% of all reports cite the source of the data.

Conclusions: Troponin is used throughout Australia to help diagnose myocardial necrosis, but there is little order in the way the results are reported or interpreted.
Conjugated bilirubin measurements in Gilbert's syndrome: method dependence
Authors: Thurlow Vanessa , Bailey Ian R , Griffiths Wyn
Published: February 2005

Background: Introducing new methodology often requires alteration to reference ranges and may cause inconvenience. Reagent suppliers may not have validated reference ranges quoted in their method sheets. When ratios of analytes are important, as for conjugated and unconjugated bilirubin, the combined changes can cause confusion.

Methods: The effect on bilirubin result interpretation following a change from Vitros (E950) dry slide technology to the Bayer ADVIA 1650 wet chemistry system was studied.

Results and conclusion: Over-estimation of conjugated bilirubin without an appropriate reference range can cause interpretative confusion. It is important to identify key patient groups likely to be affected by method changes well in advance. These need to be worked up in addition to reference range checks. It is unwise to rely on manufacturers for advice in this area. This report gives conjugated or direct bilirubin and total bilirubin values obtained using the above methods in nine patients with Gilbert's syndrome.
A Summary of Genetic Classification Using Dynamic Models of Hydrocarbon Reservoirs
Authors: Xiong-Qi Pang , Sheng-Jie Zuo , Zhi-Jun Jin , Lerche I.
Published: February 2005

Hydrocarbon reservoirs can be divided into 3 groups and 8 sub-groups. The 8 sub-groups include hydrocarbon reservoirs caused by: (i) high pressure potential fields; (ii) low pressure potential fields; (iii) release of dissolved gas from oil and water; (iv) buoyancy; (v) capillary pressure; (vi) deep-basin gas accumulations; (vii) coal-bed methane accumulations formed by molecular adsorption; and (viii) hydrate formation. The 8 sub-groups can be more broadly combined into 3 groups: (1) hydrocarbon reservoirs resulted from episodic fluid pressure, which include sub-groups (i) and (ii); (2) hydrocarbon reservoirs caused by steady and continuous hydrocarbon potential difference, including sub-groups (iii)-(v); (3) hydrocarbon reservoirs formed under unconventional conditions, which are represented by sub-groups (vi)-(viii). Hydrocarbon reservoirs with the same dynamic origin can be further subdivided into groups according to their geological settings. With different dynamic origins, various hydrocarbon reservoirs have different distribution patterns and major controlling factors. In order to enhance oil and gas field exploration and increase exploration probabilities of success, it is both important and necessary to study the dynamic mechanisms and associated genetic models for hydrocarbon migration and accumulation.
Economic Exploration Assessment of Hydrocarbon Leakage across a Fault. II. Charged Sand before Faulting
Authors: Lerche Ian
Published: February 2005

That faults cross-cut sands and cause leakage of hydrocarbons, either out of the upthrown and downthrown sand system or from the downthrown sand to the upthrown sand, is well known The decision to drill either or both of such sands depends on what it is one assesses as the likely hydrocarbon potential of the total system and also for each sand independently. This paper provides a quantitative procedure to determine a strategy for deciding what to drill.

The economic worth for such a sand system depends on the chances the sands were originally hydrocarbon charged, and on the leakage possibilities for each sand, together with the recharge of the upthrown sand from the downthrown sand, and seems not to have received a quantitative investigation to date. In addition, at the exploration stage the amount of detailed information about such a fault cut system is limited, so that any and all assessments of parameters influencing the economic worth are also uncertain. This paper shows how one can include uncertainties caused by such “fuzzy” parameters in attempting to decide on a drilling strategy geared to satisfying corporate mandated economic returns criteria. Numerical illustrations are given to show how the strategies to decide to drill either only the downthrown sand, or only the upthrown sand, or to drill both sands can be brought to a rational form so that corporate decision-makers can compare and contrast the three strategies under the same quantitative framework.
Economic Exploration Assessment of Hydrocarbon Leakage across a Fault. I. Charged Sand after Faulting
Authors: Lerche Ian
Published: February 2005

This paper concerns itself with providing economic estimates for hydrocarbon Exploration when a sand is offset by a fault and when the downthrown part of the sand is later charged with hydrocarbons. The fault may leak, so that hydrocarbons can be transferred to the upthrown part of the sand body or may be leaked from the system and so lost. The costs of drilling the upthrown sand are usually less than those to drill the deeper sand. However, it is in general unknown what fraction of the original hydrocarbon charge is reassigned to the upthrown side and what fraction is leaked away. Also unknown is the probability that the fault leaks. The economic assessment is then made up of three possibilities: drill only the downthrown sand; drill only the upthrown sand; or drill both components of the sand. The concern is with estimating the best strategy to follow to maximize the value to be gained from the system. This paper shows how to provide such an economic assessment.

The more complex problem of hydrocarbons already in the sand before the fault occurs will be taken up in the next paper, together with uncertainties and their influence on assessed worth, when none of the potential gains, costs, leak probability, or the chance the sands were hydrocarbon charged, are known with any degree of precision. The dominance of each to the uncertainty of economic worth will also be considered.
Adsorption of Aniline from Aqueous Solution Using Copper-Exchanged ZSM-5 and Unmodified H-ZSM-5
Authors: O'Brien J. , Curtin T. , O'Dwyer T.F.
Published: February 2005

Three medium-pore aluminosilicates were investigated with a view to examining their potential as adsorbents for the removal of aniline from aqueous solutions. H-ZSM-5 was exchanged with copper to prepare two different metal-loaded zeolites. The aqueous stability of the copper-exchanged zeolites was then examined by assessing the quantity of copper leached from each zeolite into solution as a function of pH. The optimum stability range with minimal copper leaching occurred between pH values of 5 and 9. The adsorption of aniline from aqueous solution onto each of the three zeolites was carried out within this pH window and the influence of the exchanged copper on the uptake level was assessed. The sorption experiments indicated an uptake level of approximately 40 mg/g for each zeolite. In all cases, the process followed the Langmuir adsorption model with the level of aniline adsorbed being largely unaffected by a change in temperature or the presence of extra-framework copper.
Thorium Ion Uptake by Zeolite a Synthesized from Natural Clinoptilolite Tuffs
Authors: Faghihian H. , Maragheh M.G. , Amini M.K. , Nezamzadeh A.R.
Published: February 2005

Natural clinoptilolite tuffs from the Semnan region of Iran were used for the synthesis of zeolite A. The tuffs and synthesized zeolite were characterized by XRD and XRF methods. The sorption behaviour of the synthesized zeolite towards thorium ions was studied. The corresponding adsorption constant was calculated using the Lagergren equation. The measured values of the distribution coefficient (Kd) indicated that Th(IV) ion uptake was higher at lower initial concentrations, higher temperature and higher pH values. The thermodynamic parameters for the exchange were calculated through the construction of ion-exchange isotherms at 298, 323 and 343 K, respectively. The dynamic adsorption of Th(IV) ions was also studied by passing the solution through a column in the presence and absence of sodium ions.
Polarising Ability of the Metal Surface Atoms of a Catalyst and the Work Function
Authors: Stokłosa Andrzej , Kurek Stefan S. , Laskowska Barbara
Published: February 2005

An attempt was made to determine the polarising ability of metal surface atoms. On the basis of an analysis of the metal cohesive energy and the electron binding energy in ionic cores, a new parameter was proposed called the polarising ability of surface atoms as defined by the equation:

[Formula: see text]

where EEBE denotes the electron binding energy at the outermost shell of the ionic core, the product (αδG0sub) determines the surface Gibbs energy that is proportional (the quantity α denoting the proportionality factor) to the standard Gibbs energy of sublimation of the metal (δG0subM), r is the metallic radius (half the length of the metallic bond), ao is the radius of the first Bohr orbit and R is the Rydberg constant.

It was shown that the above parameter is proportional to the work function and that, in a similar fashion to the ionisation energy of ions, this can indicate the polarising ability of the surface atoms. The correlation between the polarising ability parameter and the initial heat of adsorption of H2, O2, CO and N2, and between the limiting exchange current (log io) of the hydrogen evolution on metals, was demonstrated.
Dual Purpose Design of Small Wind Turbine Blades
Authors: Wood D. H.
Published: February 2005

Experimental studies of the starting behaviour of small wind turbines have shown that the initial “idling period”, characterised by small rotor acceleration, is usually much longer than the subsequent period of rapid accleration to reach operational rotor speed. Idling obviously reduces the power generation potential of any turbine. The experimental results also imply that most starting torque is generated near the hub, whereas power-producing torque is concentrated near the tip. Therefore this paper considers the computational design of blades for small wind turbines for the dual purposes of (i) efficient power production at rated wind speeds and (ii) rapid starting at smaller wind speeds. Standard blade element theory is used to determine the power coefficient, which is the first objective function to be maximised. A modified blade element method gives the start, whose inverse is the second objective function. During the idling period, the blade angles of attack are relatively large, allowing the lift and drag to be modelled using “generic” flat-plate equations with a small adjustment for the particular aerofoil. No power is extracted from the wind while the blades are accelerated by the aerodynamic torque. Starting is deemed to be complete at a tip speed ratio representing the end of the idling period, which considerably less than the period for power generation.

The design is by “differential evolution”. An initial population of blade types is generated randomly and allowed to evolve through random modification and selection of the fittest blades to comprise the next generation. The blade “genes” are the chord and pitch of each blade element; the aerofoil section is the same for all elements and all blades. In multi-objective optimisation, most interest focusses on the members of the population which have at least one objective function greater than every other member, as the final design is usually chosen from these blades. The geometry of the best power extracting blade obtained from the evolutionary optimisation was compared with that arising from standard blade element theory. Good agreement was found for the case of an aerofoil having a pronounced peak in its lift to drag ratio but only a small Reynolds number dependence in the lift coefficient at which the ratio is a maximum. Using an aerofoil with a much flatter lift to drag characteristic, the evolutionary method easily adapted to the significant Reynolds number dependence of the aerofoil characteristics. The effects of blade inertia and the resistive torque of the generator and drive train are also considered. In all cases studied, the best power-producing blade always had relatively poor starting performance, but it was usually possible to choose an alterntive blade with only a small reduction in power output but with a starting time decreased by a factor of around two.
Analysis of the Barriers for the Hydrogen Energy Technology in Stand-Alone Power Systems
Authors: Tsoutsos T.D. , Zoulias E.I. , Lymberopoulosa N. , Glöckner R.
Published: February 2005

The integration of hydrogen technologies in renewable energy systems of remote areas is expected to be a challenging development in the foreseeable future, since hydrogen can be generated and stored in large quantities, can be produced on site, does not produce polluting gas or other emissions and has a high energy content (enthalpy) per unit weight. However, such development has to overcome significant barriers, such as high capital cost and limited experience and availability of equipment. Nevertheless, there is a large potential for applications and so a normal market development, with reducing costs, can be expected. This paper presents the results and recommendations of an international workshop on market potential analysis for the introduction of hydrogen energy technology in stand-alone power systems.
Modelling the Control of an Isolated Power System Based on Diesel and Pitch Controlled Wind Generation
Authors: Mufti Mairajud – din , Balasubramanian R. , Lone S. A. , Tripathy S. C.
Published: February 2005

This paper deals with the control of a stand alone power system comprised of a pitch controlled wind turbine and two diesel units. First, a single-input single-output (SISO) self-tuning regulator (STR) is designed for blade-pitch control, with a conventional diesel governor control. Then, a two-input two-output (TITO) STR is used for coordinated pitch and diesel governor controls. Finally a case study is made with a superconducting magnetic energy storage unit (SMES), introduced as a damping device. In this case, a three-input three-output STR controls the wind-diesel-SMES system in a co-ordinated manner. The design of the various control schemes ensures that the system performs well under both wind and load disturbances.
Design of Grid-Connected Induction Generators for Wind Power Generation
Authors: Balamurugan K. , Slochanal S. Mary Raja , Vijayalakshmi N.
Published: February 2005

The design of an induction machine for grid connected wind energy applications should be different from isolated wind electricity generation and motor applications. Commonly, standard induction machines are used as grid connected induction generators. However, such machines are designed for motor operation and have more reactive power consumption and greater no-load losses than necessary.

This paper presents a design for an induction generator exclusively for grid connected applications by reducing both reactive power consumption and no-load losses. The theoretical performance of the proposed generator is compared with the conventional induction motor used as a generator. Evolutionary programming is used as a tool for design optimization of both generator and motor.
Estimation of Cut-In and Shut-Down Wind Speed for a Grid Connected Wind Turbine
Authors: Coxon S.
Published: February 2005

The Gazelle 22 kW wind turbine is grid connected with an induction generator used as a motor at cut-in. Unnecessary cut-ins reduces net power generation. Development of the control system of the grid connected Gazelle wind turbine highlighted a problem when values of the measured local wind speed were used to disconnect and reconnect the turbine. The measured wind speed at shut down is less than when the blades are stationary, as related to the induction factor. Experiments were performed to investigate this difference, allowing the results to be used within the design of the turbine controller. This gave improved net power generation.
Potential of Autonomous/Off-Grid Hybrid Wind-Diesel Power System for Electrification of a Remote Settlement in Saudi Arabia
Authors: Shaahid S. M. , El-Amin I. , Rehman S. , Al-Shehri A. , Bakashwain J. , Ahmad F.
Published: February 2005

In the present study, hourly mean wind-speed data recorded at Rafha, Saudi Arabia, have been analyzed for the potential of utilising autonomous hybrid (wind-diesel) power systems to meet the load requirements of a typical remote settlement, namely Rawdhat Bin Habbas, near Rafha and with a population of 10,000 and having an annual electrical energy demand of 13,200 MWh. The monthly average wind speeds range from 2.7 m/s to 4.2 m/s at 10 m height. The hybrid systems considered consist of different combinations of 1.3 MW commercial wind machines supplemented with diesel generators. National Renewable Energy Laboratory's (NREL's) HOMER software has been used to evaluate the potential of hybrid wind-diesel power systems.

The study indicates that for a hybrid system consisting of 3.9 MW (three 1.3 MW wind machines, 50 m hub-height) wind farm capacity together with 4.5 MW diesel system (three 1.5 MW units), the simulated wind penetration is 24 %. The cost of electricity from this hybrid configuration is calculated to be 0.078 $/kWh (assuming a diesel fuel price of 0.1 $/litre). The results confirm that the number of operational hours of diesel generators in this wind-diesel system decreases with increase in wind farm capacity. Emphasised are: wind penetration, reducing excess energy production, un-met load, cost of energy, effect of hub-height on energy production, fuel-savings/reduction-in-carbon-emissions (relative to the diesel-only situation).
Effect of Surface Roughness on the Aerodynamic Characteristics of a Symmetrical Airfoil
Authors: Chakroun Walid , Al-Mesri Issa , Al-Fahad Sami
Published: February 2005

The objective of this study is to investigate the effect of surface roughness by varying the roughness size and location on the aerodynamic characteristics of the airfoil. Tests were conducted on the symmetrical airfoil models NACA 0012 on which the nature of the surface was varied from smooth to very rough and at a chord Reynolds number of 1.5*105. Different airfoil models with various roughness sizes and roughness locations were tested for different angles of attack. Lift, drag and pressure coefficients were measured and velocity profiles were determined for the smooth and grit 36 roughened models.

It is shown that as the surface roughness increases, the minimum drag also increases due to the increase of the skin friction and the lift decreases. Surface roughness is seen to delay the stall angle and also increase the lift in the stall region.

The airfoil model with the roughness located at the trailing edge shows minimum drag and maximum lift up to the stall angle compared to the other cases of different roughness locations. It is confirmed that, for the rough surface, a turbulent boundary layer exists where the laminar boundary layer is encountered for the smooth surface at the same Reynolds number. The measured skin friction for the rough surface is larger than that for the smooth surface.
Negotiating Sustainable Consumption: A Review of the Consumption Debate and its Policy Implications
Authors: Jackson Tim
Published: February 2005

Concern over the environmental and social implications of modern consumption patterns has emerged as a defining feature of debates about sustainable development. During the last decade, these concerns have crystallised around the concept of ‘sustainable consumption’. This paper briefly reviews the recent history of this debate. It highlights, in particular, the failure of policy-makers to agree on precise definitions of sustainable consumption and the contentious nature of exhortations to ‘consume less’. In spite of these difficulties, the author suggests that progress towards understanding and changing unsustainable patterns of consumption is not only necessary but possible. Such progress relies, however, on two key understandings: Firstly, an informed view of the wider and deeper debates about consumption and consumer behaviour within which the sustainable consumption debate sits; and secondly, a culturally open approach to the role of policy in negotiating change. The paper highlights, in particular, the potential for community-based initiatives for social change. Far from offering an intractable policy domain, the author argues that a sophisticated understanding of the social and institutional context of consumer action opens out a much more creative vista for policy innovation than has hitherto been recognised.