bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutrient induced thermogenesis during major colorectal excision – a pilot study
Authors: Chandrasekaran T. V. , Morgan R. N. W. , Mason R. A. , Mangat P. S. , Watkins A. J. , Carr N. D.
Published: December 2004

Objective  Hypothermia may occur during general anaesthesia and is associated with postoperative coagulopathy, ischaemic cardiac events, wound infections and increased metabolic expenditure due to shivering. The purpose of the present pilot study was to determine whether the administration of certain amino acids (Vamin 18) during general anaesthesia could prevent postoperative hypothermia.

Patients and methods  Two groups of patients were studied. The study group comprised 10 patients who underwent complex major colorectal operations. In this group an infusion of 500 mls of Vamin 18 (Fresenius Kabi Ltd) was commenced immediately after induction of anaesthesia but prior to the skin incision. In a control group (n = 10) who underwent similar surgical procedures Vamin 18 was not administered. In both groups core body temperature, using an oesophageal probe was recorded during the procedure and recovery period. Ambient theatre and recovery room temperature and other body warming techniques were standardized for all patients. Statistical analysis was performed using t‐test for comparison of linear temperature changes at different times during the procedure for both groups of patients.

Results  The body temperature was statistically significantly reduced in both groups at skin incision when compared with temperature prior to induction of anaesthesia. (Study group: mean 0.74°C, SD = 0.38, P =<0.001; Control group: mean 0.54°C, SD = 0.43, P = 0.003]. The increase in body temperature between the time of skin incision and recovery period was statistically significant (P = 0.012) in the study group but not so in the control group (P = 0.730).

Conclusion  The results of the present pilot study demonstrate that complex colorectal operations are associated with a decrease in body temperature which is most marked immediately after the induction of anaesthesia. The perioperative administration of Vamin 18 appears to increase the rate of recovery of body temperature. The impact of this thermogenic effect on perioperative morbidity and mortality should be studied in a prospective randomised clinical trial.
Soluble transferrin receptors and ferritin in Type 2 diabetic patients
Authors: Hernández C. , Lecube A. , Carrera A. , Simó R.
Published: December 2004

Aim To determine circulating transferrin receptor levels (sTfR) in Type 2 diabetic patients to evaluate whether serum ferritin reflects iron body stores or inflammation in diabetic population.

Methods A total of 84 consecutive Type 2 diabetic patients and 60 healthy subjects matched by age and gender were included in this case‐control study. Ferritin concentration was measured by a turbidimetric method and sTfR concentration were determined by nephelometry.

Results Diabetic patients have higher serum ferritin levels than control subjects [114 ng/ml (12–831) vs. 74 ng/ml (11–697);P = 0.006]. However, no differences in sTfR concentrations were observed between both groups [1.27 mg/l (0.69–2.47) vs. 1.24 mg/l (0.77–2.80);P = NS]. A negative correlation between ferritin and sTfR concentration was detected in control subjects but not in diabetic patients.

Conclusions Serum ferritin levels are increased in Type 2 diabetic patients in the absence of a reciprocal decrease of sTfR. This finding suggests that elevated ferritin levels in Type 2 diabetes are mainly as a result of inflammatory mechanisms rather than iron overload.
Hospital in‐patients with diabetes: increasing prevalence and management problems
Authors: Wallymahmed M. E. , Dawes S. , Clarke G. , Saunders S. , Younis N. , MacFarlane I. A.
Published: December 2004

Aims  To re‐assess the prevalence, management problems, clinical outcomes and discharge summaries of hospital in‐patients with diabetes.

Methods  Case records of all patients occupying in‐patient beds were audited on a single weekday in 2003 in a large urban hospital and repeated after 3 months. Data was compared with an identical audit 12 years previously.

Results  Over 12 years the number of beds available for admission (1191) had reduced by 25% with a bed occupancy of 97%. Diabetes prevalence had increased from 7.0% to 11.1% (P < 0.01) (97% Type 2). Diabetes management was considered inappropriate in 29%, more than in 1991 (20%). After 3 months, discharge summaries had been completed on 75% of patients but diabetes was mentioned in only 53%.

Conclusion  The prevalence of in‐patient diabetes (11.1%) was over 50% greater and diabetes management was suboptimal in more patients than in 1991. In many length of stay was prolonged and almost half of the discharge summaries did not mention diabetes. These findings have major implications for service delivery and resource planning.
Insulin pump therapy in children and adolescents: improvements in key parameters of diabetes management including quality of life
Authors: McMahon S. K. , Airey F. L. , Marangou D. A. , McElwee K. J. , Carne C. L. , Clarey A. J. , Davis E. A. , Jones T. W.
Published: December 2004

Aims  To determine the impact of insulin pump therapy (continuous subcutaneous insulin infusion) on key parameters of diabetes management including quality of life in children and adolescents with Type 1 diabetes mellitus (T1DM).

Methods  All patients started on insulin pump therapy were prospectively followed before and after institution of insulin pump therapy. Data collected included age, duration of diabetes, glycated haemoglobin levels (HbA1c), anthropometric data and episodes of severe hypoglycaemia defined as hypoglycaemia resulting in coma or convulsion. A subset of patients also completed the Diabetes Quality of Life Instrument (DQOL) and Self‐Efficacy for Diabetes Scale (SED) questionnaires to assess quality of life.

Results  At the time of analysis, 100 patients had been managed with insulin pump therapy. The mean age when starting pump therapy was 12.5 (3.9–19.6) years. Duration of therapy ranged from 0.2 to 4.0 years (mean 1.4 years, median 1.5 years). HbA1c decreased from 8.3 ± 0.1% prior to pump therapy to 7.8 ± 0.1% (P < 0.0001). Episodes of severe hypoglycaemia decreased from 32.9 to 11.4 per 100 patient years. Components of quality of life measures showed improvement on pump treatment. BMI standard deviation scores (z scores) did not increase.

Conclusions  Pump therapy is proving an effective means of insulin therapy in the young patient that shows promise to improve glycaemic control with a reduction in hypoglycaemia frequency. Quality of Life measures suggest that psychosocial outcomes may be improved.
Lifetime glycaemic exposure predicts reduced coronary vasoreactivity in Type 1 diabetic subjects
Authors: Sundell J. , Janatuinen T. , Rönnemaa T. , Naum A. , Laine H. , Luotolahti M. , Nuutila P. , Raitakari O. T. , Knuuti J.
Published: December 2004

Aims  Subjects with Type 1 diabetes have impaired coronary vasoreactivity but the independent role of glycaemic control on myocardial perfusion is less clear. We examined the effect of lifetime glycaemic exposure on coronary vasoreactivity in 43 otherwise healthy Type 1 diabetic subjects.

Methods  Myocardial blood flow was calculated basally and during pharmacologically induced hyperaemia in the fasting state and during euglycaemic hyperinsulinaemic clamp (at an insulin infusion rate of 1 mU/kg per min for 60 min) using positron emission tomography and 15O‐water. Glycaemic exposure was estimated as glycosylated haemoglobin A1c (HbA1c) months.

Results  Hyperaemic myocardial blood flow was inversely associated with log HbA1c months in the fasting state (r = −0.72, P < 0.01) and during clamp (r = −0.35, P < 0.05). These correlations remained significant after adjustment for lipid values, blood pressures, sex, smoking, body mass index (BMI) and age (r = −0.70, P < 0.05 and r = −0.35, P < 0.05, respectively). No significant correlation was detected between hyperaemic flow and HbA1c or plasma glucose values measured immediately preceding the PET study.

Conclusions  The present study demonstrates that the lifetime glycaemic exposure appears to be a better predictor of reduced coronary vasoreactivity than recent glycaemic control in Type 1 diabetic subjects. Reduced coronary vasoreactivity in diabetic subjects with poor glycaemic control and/or long duration of diabetes may represent an early precursor of coronary artery disease.
Increasing prevalence of Type 2 diabetes mellitus in all ethnic groups in Mauritius
Authors: Söderberg S. , Zimmet P. , Tuomilehto J. , De Courten M. , Dowse G. K. , Chitson P. , Gareeboo H. , Alberti K. G. M. M. , Shaw J. E.
Published: December 2004

Aims  To describe the prevalence of different stages of glucose intolerance in a population from Mauritius followed over 11 years.

Methods  Population‐based surveys were undertaken in the multiethnic nation of Mauritius in 1987, 1992 and 1998, with 5083, 6616, and 6291 participants, respectively. Questionnaires, anthropometric measurements, and a 2‐h 75‐g oral glucose tolerance test were included. Subjects aged between 25 and 75 years with classifiable data were identified; 4991, 6463 and 5392 from 1987, 1992 and 1998, respectively. Glucose tolerance was classified according to WHO 1999 criteria.

Results  The prevalence of Type 2 diabetes increased significantly during the period studied, from 12.8% in 1987, to 15.2% in 1992, and 17.9% in 1998. The increasing prevalence was seen in both men and women, and in all age groups. The prevalence of known diabetes (KDM) increased progressively, and more markedly than the increase in newly diagnosed diabetes (NDM). A diagnosis of impaired glucose tolerance (IGT) was more prevalent amongst women whereas impaired fasting glucose (IFG) was more common amongst men. The prevalences of IGT and IFG did not change markedly during the period. The prevalence of diabetes and IGT was similar for participants of Indian, Creole and Chinese background in each survey, and the increasing prevalence of diabetes was seen in all ethnic groups.

Conclusion  In this study, we report an increasing prevalence of diabetes over an 11‐year period in Mauritius. This increase was seen in both sexes, and in all age and ethnic groups, and was mainly due to an increase in the numbers of those with known diabetes.
Studies of relationships between variation of the human G protein‐coupled receptor 40 Gene and Type 2 diabetes and insulin release
Authors: Hamid Y. H. , Vissing H. , Holst B. , Urhammer S. A. , Pyke C. , Hansen S. K. , Glümer C. , Borch‐Johnsen K. , Jørgensen T. , Schwartz T. W. , Pedersen O. , Hansen T.
Published: December 2004

Aims  Recently, a novel human G protein‐coupled receptor 40 (GPR40), which is predominantly expressed in pancreatic islets, was shown to mediate an amplifying effect of long‐chain fatty acids on glucose‐induced insulin secretion. The present aim was to examine the coding region of GPR40 for variation and to assess whether identified variants confer an increased risk of Type 2 diabetes or altered insulin release.

Methods  Mutation analysis was performed in 43 patients with Type 2 diabetes, 18 normal glucose‐tolerant subjects, and 3 maturity‐onset of diabetes in the young (MODY) X patients using direct sequencing. Genotyping was performed using polymerase chain reaction (PCR)‐generated primer extension products analysis by high throughput chip‐based mass spectrometry (MALDI‐TOF). The potential impact of GPR40 mutations on [3H]‐myo‐inositol turnover was estimated in COS‐7 cells after stimulation with various concentrations of 5,8,11‐eicosatriynoic acid.

Results  Two nucleotide substitutions, an Arg211His polymorphism and a rare Asp175Asn mutation, were identified. Both variants showed EC50 values similar to the wild type. However, the maximal efficacy of the rare Asp175Asn was 39% lower compared with the wild type (P = 0.01). The Arg211His polymorphism had a similar allele frequency among 1384 Type 2 diabetic patients [MAF%; 23.4 (95% CI: 21.8–25.0)] and 4424 middle‐aged glucose‐tolerant subjects [24.1% (23.2–25.0)]. A genotype‐quantitative trait study of 5597 non‐diabetic, middle‐aged subjects from the Inter99 cohort showed no significant differences in oral glucose tolerance test (OGTT)‐derived estimates of insulin release between carriers of various GPR40 genotypes.

Conclusions  Variations in the coding region of GPR40 do not appear to be associated with Type 2 diabetes or insulin release alterations.
Previous abdominal surgery and closed entry for gynaecological laparoscopy: a prospective study
Authors: Rafii Arash , Camatte Sophie , Lelièvre Loïc , Daraï Emile , Lécuru Fabrice
Published: December 2004

Objectives  To assess the morbidity from closed laparoscopic access and define the role of previous surgery on the occurrence of these complications.

Design and Methods  We prospectively recorded data on all laparoscopic procedures between January 2000 and January 2001. We compared results from patients without previous abdominal surgery (group I) with patients with prior abdominal surgery (group II). The insertion site for the Verres needle was trans‐umbilical for patients in group I and in the left upper quadrant for patients in group II.

Setting  Gynaecology department of a University Hospital.

Population  All laparoscopic procedures between January 2000 and January 2001.

Main outcome measures  We compared results from patients without previous abdominal surgery (group I) with patients with prior abdominal surgery (group II). The insertion site for the Verres needle was trans‐umbilical for patients in group I and the left upper quadrant for patients in group II.

Results  Four hundred and seventy‐seven laparoscopies were carried out during the study period, 368 women without previous surgery were included in group I, and 109 women were included in group II. We recorded 1 complication (overall complication rate of 0.2% and 31 incidents (6.4%). One complication (small bowel injury) was related to the insertion of the Verres needle (0.2%). The incidents and complications occurred only in group II (P < 0.05). All the complications were treated by laparoscopy.

Conclusion  The complication rate of the entry step is low in gynaecological laparoscopy. A previous history of laparotomy increases the risk of these complications and incidents. Safety rules and other access method should be investigated for these patients.
Association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth
Authors: Freeman K. , Oakley L. , Pollak A. , Buffolano W. , Petersen E. , Semprini A.E. , Salt A. , Gilbert R. ,   for The European Multicentre Study on Congenital Toxoplasmosis (EMSCOT) Members of The European Multicentre Study on Congenital Toxoplasmosis (EMSCOT) are listed on page 000
Published: December 2004

Objective  To determine the association between congenital toxoplasmosis and preterm birth, low birthweight and small for gestational age birth.

Design  Multicentre prospective cohort study.

Setting  Ten European centres offering prenatal screening for toxoplasmosis.

Population  Deliveries after 23 weeks of gestation in 386 women with singleton pregnancies who seroconverted to toxoplasma infection before 20 weeks of gestation. Deliveries after 36 weeks in 234 women who seroconverted at 20 weeks or later, and tested positive before 37 weeks.

Methods  Comparison of infected and uninfected births, adjusted for parity and country of birth.

Main outcome measures  Differences in gestational age at birth, birthweight and birthweight centile.

Results  Infected babies were born or delivered earlier than uninfected babies: the mean difference for seroconverters before 20 weeks was −5.4 days (95% CI: −1.4, −9.4), and at 20 weeks or more, −2.6 days (95% CI: −0.5, −4.7). Congenital infection was associated with an increased risk of preterm delivery when seroconversion occurred before 20 weeks (OR 4.71; 95% CI: 2.03, 10.9). No significant differences were detected for birthweight or birthweight centile.

Conclusion  Babies with congenital toxoplasmosis were born earlier than uninfected babies but the mechanism leading to shorter length of gestation is unknown. Congenital infection could precipitate early delivery or prompt caesarean section or induction of delivery. We found no evidence for a significant association between congenital toxoplasmosis and reduced birthweight or small for gestational age birth.
The long term neurologic outcome of children from pregnancies complicated by twin‐to‐twin transfusion syndrome
Authors: Dickinson Jan E. , Duncombe Gregory J. , Evans Sharon F. , French Noel P. , Hagan Ronnie
Published: December 2004

Objective  To assess long term outcomes of children from pregnancies complicated by twin‐to‐twin transfusion syndrome.

Design  Comparison of children from pregnancies with twin‐to‐twin transfusion syndrome in Western Australia with a contemporaneous regional comparison cohort of preterm and term infants studied using an identical assessment procedure.

Population and setting  All infants aged ≥18 months were identified from a geographically based longitudinal cohort of monochorionic twin pregnancies with an antenatal diagnosis of twin‐to‐twin transfusion syndrome conducted prospectively since 1992.

Methods  Children were evaluated using age‐specific developmental and behavioural assessments. Cerebral palsy was diagnosed clinically and ascertainment confirmed through the Western Australian Cerebral Palsy Register.

Main outcome measures  Intellectual disability, cerebral palsy, behavioural and cognitive function.

Results  Fifty‐two children were identified as eligible for study and assessments were performed on 49 (94%). Three surviving children had a diagnosis of cerebral palsy (5.8%). The mean IQ score was 8 points lower in twin‐to‐twin transfusion syndrome children compared with the comparison cohort although this was mainly due to a decrement of 13 points in those born before 33 weeks of gestation. There was no difference between the donor and the recipient twin in terms of IQ scores (median difference −3, 95% CI −9 to 6). There was no relationship of IQ score to the worst stage of the twin‐to‐twin transfusion syndrome. Child Behavior Check List and Vineland Adaptive Behavior Scale scores did not differ between twin‐to‐twin transfusion syndrome children and the comparison group.

Conclusions  Twin‐to‐twin transfusion syndrome is associated with a significant reduction in IQ score in very preterm survivors. There seems to be no increase in the prevalence of cerebral palsy. Overall behaviour and adaptive behaviour scale scores are similar to a comparison group.
Total laparoscopic hysterectomy as a primary surgical treatment for endometrial cancer in morbidly obese women
Authors: Yu C.K.H. , Cutner A. , Mould T. , Olaitan A.
Published: December 2004

To evaluate the feasibility of total laparoscopic hysterectomy as the primary treatment for endometrial cancer in morbidly obese women, an audit was carried out during an 18‐month period in a tertiary referral centre for gynaecological oncology. Four women who had laparoscopic surgery were compared with a similar cohort who had open surgery. The mean operating time was equivalent, without evidence of excess morbidity with the laparoscopic approach. However, inpatient stay was longer with open versus laparoscopic surgery (11.5 vs 4 days). Laparoscopic surgery is safe to use in morbidly obese women with endometrial cancer.
Repeated measures screening for Down's Syndrome
Authors: Wright David E. , Bradbury Ian
Published: December 2004

Objective  To demonstrate the potential value of screening for Down's Syndrome using highly correlated repeated measures of serum markers taken in the first and second trimesters of pregnancy.

Design  A Monte Carlo simulation study.

Population  Detection rates and false positive rates relating to the maternal age distribution of England and Wales for the period 1996 to 1998 were obtained using marker distributions from the SURUSS study.

Results  Screening using first trimester nuchal translucency and repeated measures of uE3 and PAPP‐A in the first and second trimester has an estimated false positive rate of 0.3% for an 85% detection rate. This should be compared with the integrated test with an estimated false positive rate of 1.2% for the same detection rate.

Conclusions  The performance of repeated measures screening tests, and their acceptability to women, should be assessed in further prospective studies.
An extended episode of early Mesoproterozoic metamorphic fluid flow in the Reynolds Range, central Australia*
Authors: WILLIAMS I. S. , BUICK I. S. , CARTWRIGHT I.
Published: December 2004

ABSTRACT The products of metamorphic fluid flow are preserved in zones within the marbles and metamorphosed semipelites of the Upper Calcsilicate Unit in the granulite portion of the Late Palaeoproterozoic Reynolds Range Group, northern Arunta Block, central Australia. The zones of retrogression, characterized by minerals such as wollastonite, grossular and clinohumite, local resetting of oxygen isotopic compositions and local major element metasomatism, were channelways for water‐rich fluids derived from granulite facies metapelites. U–Th–Pb isotopic ages measured by the SHRIMP ion microprobe on zircon and monazite from a granulite facies semipelite, an early semiconcordant aluminous quartz‐rich fluid‐flow segregation and a late discordant quartz‐rich segregation record some of the extended thermal history of the area. Zircon cores from the semipelite show its likely protolith to be an igneous rock 1812 ± 11 Ma old, itself derived from a source containing zircon as old as 2.2 Ga. Low‐Th/U overgrowths on the zircon grew during granulite facies metamorphism at 1594 ± 6 Ma. Monazite cooled to its blocking temperature at 1576 ± 8 Ma. Zircon cores from the semiconcordant segregation are dominantly >2.3 Ga old, indicating that the source of the fluids was not the particular metamorphosed semipelite studied. Two generations of low‐Th/U overgrowths on the zircon give indistinguishable ages for the older and younger of 1589 ± 8 and 1582 ± 8 Ma, respectively. The monazite age is the same, 1576 ± 12 Ma. Zircon from the late discordant segregation gave 1568 ± 4 Ma. Fluid flow occurred for at least 18 ± 3 (σ) Ma and ended 26 ± 3 (σ) Ma after the peak of metamorphism, suggesting a very slow cooling rate of ∼3°C Ma–1. The last regional high‐grade metamorphism in the Reynolds Range occurred at ∼1.6 Ga, not ∼1.78 Ga as previously thought. The high‐grade event at ∼1.78 Ga is a separate event that affected only the basement to the Reynolds Range Group.
Metallogenesis of the late Pan‐African gold‐bearing East Ouzzal shear zone (Hoggar, Algeria)
Authors: MARIGNAC CH. , SEMIANI A. , FOURCADE S. , BOIRON M.‐C. , JORON J.‐L. , KIENAST J.‐R. , PEUCAT J.‐J.
Published: December 2004

In the W Hoggar (Algeria), the major transcurrent N–S East Ouzzal shear zone (EOSZ) hosts several world‐class gold deposits over a 100‐km length. The late Pan‐African EOSZ separates two contrasting Precambrian domains: the Archaean In Ouzzal block to the west (orthogneisses with subordinate metasediments, reworked and granulitized in the c. 2 Ga Eburnean event) and a Middle Proterozoic block to the east (again orthogneisses and metasediments, involved in the c. 600 Ma Pan‐African event).

The EOSZ is a mylonite belt, 1–3 km wide, with a 50‐m‐wide ultramylonite belt hosting numerous quartz veins and lenses (giant hydrothermal quartz system) associated with a quartz‐sericite‐pyrite‐carbonate (beresite) alteration. These hydrothermal events occurred under ductile (evolving towards brittle) conditions, between 500 and 300 MPa, at 500–300°C, with aqueous‐carbonic fluids derived both from underlying devolatilized metamorphic rocks and a mantle source, as recorded by stable (C, O) isotope data. No gold mineralization was associated with these typical mesothermal events.

Following a pressure drop (to 130 MPa), related to the inception of extensional tectonics, the EOSZ was later percolated by a new set of hydrothermal fluids, evolved from basinal waters that deeply penetrated into the In Ouzzal basement. These fluids were Ca‐bearing brines (up to 25% wt. eq. NaCl), characterized by high δD (‐9 to + 18‰ range), mobilized by the thermal energy released by the late Pan‐African granite magmatism (Taourirt granites).

As demonstrated by Pb isotope data, the brines leached Au from the In Ouzzal granulites (which contain 3 ppb Au). Fluid inclusion studies indicate that gold was deposited from these brines in the EOSZ at a depth of c. 5 km, due to mixing and cooling with descending diluted fluids.
Geochemistry and isotope (Sr, Nd, O) study of Al–Mg granulites from the In Ouzzal Archaean block (Hoggar, Algeria)
Authors: BERNARD‐GRIFFITHS J. , FOURCADE S. , KIENAST J.‐R , PEUCAT J.‐J. , MARTINEAU F. , RAHMANI A.
Published: December 2004

The In Ouzzal Al–Mg granulites are found within sedimentary units deposited after 2.7 Ga, the whole association being metamorphosed under extreme temperature conditions (c.1000 °C) at 2 Ga. The Al–Mg granulites are interlayered with other metasediments, including metapelites, quartzites and magnetite‐bearing quartzites, forsterite‐spinel marbles, and a few meta‐igneous rocks (mainly pyroxenites). They do not occur at a specific position in the sedimentary suite, and they do not reflect any particular structural control.

The major and trace element compositions of Al–Mg granulites (especially the high Cr, Ni, Co contents) show that their peculiar ‘refractory’ chemistry is more compatible with premetamorphic sedimentary characteristics rather than with metasomatic, metamorphic or partial melting processes. Sedimentary admixtures of a common mature detrital component coming from the weathering of the local acidic igneous crustal protoliths (normal pelitic component) with an extremely immature component derived from reworking of basic/ultrabasic lithologies (Al–Mg–Cr–Co–Ni–rich chloritic component) is consistent with the geochemistry of such rocks.

As in other instances, the quartz‐garnet oxygen isotopic thermometer here records an apparent temperature close to the peak metamorphism (c.1000 °C). Although the persistence of pre‐existing δ18O variations on a small scale during the metamorphism does not support a major pervasive fluid flow during metamorphism, it does not rule out the presence of syn‐ to post‐metamorphic CO2. The low δ18O (c.+ 5 to + 6‰) of the most typical Al–Mg granulites indicate that the ‘chloritic component’ in these rocks was derived from hydrothermally altered mafic/ultramafic protoliths rather than dominantly from palaeosols. It is suggested that the presence of such Al–Mg–Cr–Co–Ni–rich sediments is indirect evidence for the presence of greenstone belts in the local crust of the In Ouzzal at 2.6–2.7 Ga.
How well known are the thermodynamics of Fe–Mg–Ca garnet? Evidence from experimentally determined exchange equilibria
Authors: GUIRAUD M. , POWELL R.
Published: December 2004

ABSTRACT Many thermodynamic calculations relating to metamorphic rocks hinge on the thermodynamic parameters of garnet. Though some models are widely used, it is not clear whether their underlying premise is correct: that a single set of equations can be written for the activities of the end‐members of garnet covering the whole compositional range. A voluminous body of data can be used to constrain the thermodynamics of garnet, namely Fe–Mg exchange experimental data involving garnet and another mineral, particularly clinopyroxene, orthopyroxene and olivine. However, examination of these data reveals inconsistencies, apparently stemming from differences between the thermodynamics of low‐Ca and high‐Ca garnets, with a boundary of about XgCa= 0.15. In the two regions, for the high P–T of the experimental data, the thermodynamics follow the regular model, with values for the interaction parameters in the low Ca region of about wgFeMg= 50R and waFe–wgMgCa=– 1300R, in which R is the gas constant, and in the high Ca region of about wgFeMg= 1100R and wgCaFe–wgMgCa=– 2200R. Using the subregular, rather than the regular, model does not remove the discrepancy. The cause of the discrepancy needs to be identified if reliable calculations on rocks are to be made.
Desertification alters regional ecosystem–climate interactions
Authors: Asner Gregory P. , Heidebrecht Kathleen B.
Published: December 2004

We studied the spatial patterns and temporal dynamics of vegetation structural responses to precipitation variation in grassland, transitional, and desertified‐shrubland ecosystems in an 800 km2 region of Northern Chihuahua, USA. Airborne high‐fidelity imaging spectroscopy data collected from 1997 to 2001 provided spatially detailed measurements of photosynthetic and senescent canopy cover and bare soil extent. The observations were made following wintertime and summer monsoonal rains, which varied in magnitude by >300% over the study period, allowing an assessment of ecosystem responses to climate variation in the context of desertification.

Desertification caused a persistent increase in both photosynthetic vegetation (PV) and bare soil cover, and a lasting decrease in nonphotosynthetic vegetation (NPV). We did not observe a change in the spatial variability of PV cover, but its temporal variation decreased substantially. In contrast, desertification caused the spatial variability of NPV to increase markedly, while its temporal variation did not change. Both the spatial and temporal variation of exposed bare surfaces decreased with desertification. Desertification appeared to be linked to a shift in seasonal precipitation use by vegetation from mainly summer to winter inputs, resulting in an apparent decoupling of vegetation responses to inter‐annual monsoonal variation. Higher winter rainfall led to decreased springtime spatial variability in the PV cover of desertified areas. Higher summer rainfall resulted in decreased PV cover variation in grassland, transition and desertified‐shrubland regions. The effects of desertification on NPV dynamics were more than three times greater than on PV or bare soil dynamics. Using remotely sensed PV and NPV as proxies for net primary production (NPP) and litter dynamics, respectively, we estimated that desertification decreases the temporal variability of NPP and increases spatial variation of litter production and loss. Quantitative studies of surface biological materials and ecosystem processes can now be measured with high ‘structural’ detail using imaging spectroscopy and shortwave‐infrared spectral mixture analysis.
Protective Effect of Vitamin E in an Animal Model of LPS‐Induced Inflammation
Authors: Mayorga M. , Iborra A. , Estany S. , Martínez P.
Published: December 2004

Problem:  Many sterility outcomes may be associated to the presence of an inflammatory response that would lead to an inability of the endometrium to support implantation and maintain viable embryos. We have established an animal model of inflammation in which the systemic administration of lipopolysaccharyde (LPS) results in a low embryo implantation rate. The purpose of this work was to investigate the effect of the inflammatory agent LPS on embryo viability and to verify the ability of vitamin E to modulate the inflammatory effect of LPS on embryo viability.

Method of study:  For pre‐implantation studies B6CBAF1 mice, which were intraperitoneally inoculated with LPS (4–10 mg/kg), were used. Mice were also treated with vitamin E (4–10 mg/kg) before or after LPS injection. Embryos were obtained from the oviduct after each treatment.

Results:  The LPS produces a decrease in the number of pre‐implantational embryos in a concentration dependent manner. The LPS effect can be partially reversed or prevented by vitamin E. Preliminary results show that inflammatory cytokines are secreted by intraperitoneal macrophages in LPS treated mice.

Conclusion:  Our results demonstrate the ability of vitamin E to avoid an inflammatory environment and to allow viability of embryos.
B‐ and T‐cells in the Follicular Fluid and Peripheral Blood of Patients Undergoing IVF/ET Procedures
Authors: Vujisić Sanja , Lepej Snježana Židovec , Akšamija Alenka , Jerković Lidija , Sokolić Božica , Kupešić Sanja , Vince Adriana
Published: December 2004

Problem:  To analyse percentage of total and memory CD27+ B‐cells and other lymphocyte subpopulations in the peripheral blood (PB) and follicular fluid (FF) of infertile married couples.

Method of study:  Forty‐eight couples from in vitro fertilization/embryo transfer (IVF/ET) programme were divided into four groups: patients with previous unsuccessful fertilization (n = 13), ectopic pregnancy (n = 8), multiple (at least three) failed IVF/ET (n = 18) and missed abortions (n = 9). Control group consisted of 15 married couples with healthy children.

Results:  PB memory CD27+ B‐cells were significantly decreased in all groups of infertile patients compared with controls. First group had increased memory B‐cells percentages compared with the second group. The differences in the percentages of PB memory B‐cells in third and fourth group compared with the first group were not statistically significant. FF memory B‐cells in the first and third group were significantly increased compared with second and fourth group. The percentage of total FF B‐cells in all groups were significantly decreased compared with their percentage in PB. Male partners of women from the first group had had significantly increased percentages of memory B‐cells compared with the partners of women from the second group. Percentage of total T‐ and B‐cells, CD4+ and CD8+ T‐cells, NK cells and activated HLA‐DR+ T‐cells in all groups were not significantly different from controls. We found no statistically significant difference between immunoglobulin E levels in all groups of patients. We found lower levels of IgA and IgM in FF compared with serum in all groups.

Conclusion:  Infertile patients have significantly decreased percentage of CD27+ B‐cells in the PB. Abnormalities in the memory B‐cell compartment may contribute to the pathogenesis of infertility. In the T‐cell compartment abnormalities were not detected. It appears that hormonal stimulation did not influence cellular immunity parameters.
Job Complexity, Performance, and Well‐being: When Does Supplies‐Values Fit Matter?*
Authors: SHAW JASON D. , GUPTA NINA
Published: December 2004

We extend person–job fit research by investigating job performance as a moderator of the supplies–values fit relationship with strain outcomes (somatic complaints and depression). Drawing on cybernetic stress and psychological centrality perspectives, we argue that supplies–values misfit relates to lower well‐being levels when job performance is low but that this effect is attenuated when job performance is high. The results are consistent with this prediction across 3 studies that provide progressively more rigorous tests of the hypothesis. Implications of the results for theoretical and empirical person–job fit research are addressed.
Can Changes in Differential Dropout Rates Reduce Adverse Impact? A Computer Simulation Study of a Multi‐wave Selection System
Authors: TAM ANITA P. , MURPHY KEVIN R. , LYALL JOSEPH T.
Published: December 2004

A simulation was used to explore the effects of variations in the rate at which applicants drop out of selection processes on racial differences in selection outcomes. Archival data was used to simulate a realistic range of selection scenarios in which test score differences between groups and selection ratios varied. The basis for dropping out was manipulated in two separate studies. Study 1 simulated dropout decisions that occurred at random within racial subgroups; in this study, dropout rates of minority versus White candidates were varied. Study 2 examined dropout decisions that occurred as a function of test scores. Results from both studies showed that mean test score differences between White and minority applicants have the largest influence on adverse impact. Interventions designed to reduce the tendency of minority applicants to withdraw from selection are likely to have, at best, small effects on the adverse impact of selection tests.
The Impact of Poor Performers on Team Outcomes: An Empirical Examination of Attribution Theory*
Authors: TAGGAR SIMON , NEUBERT MITCHELL
Published: December 2004

We test assertions that attribution theory (AT) can explain the responses of peers to the characteristics of a poor performing team member. Study 1 assessed the processes used to interpret the behavior of a poor performer and found that behavioral manifestations of cognitive ability (g) and Conscientiousness were associated with causal attributions (locus, controllability, and stability), emotional and cognitive reactions, and behavioral intentions to help or punish a fellow team member. Building on Study 1, Study 2 focused on team level responses to the lowest performer. It assessed the impact of g/Conscientiousness of a poorly performing team member on involving others, communication, feedback, and citizenship behaviors of team members at the team level. Both studies converged in finding that individual team members' intentions to help or punish were related to poor performer traits.
Relation between early life socioeconomic position and all cause mortality in two generations. A longitudinal study of Danish men born in 1953 and their parents
Authors: Osler Merete , Andersen Anne-Marie Nybo , Batty G David , Holstein Bjørn
Published: December 2004

Objective:To examine (1) the relation between parental socioeconomic position and all cause mortality in two generations, (2) the relative importance of mother’s educational status and father’s occupational status on offspring mortality, and (3) the effect of factors in the family environment on these relations.

Design:A longitudinal study with record linkage to the Civil Registration System. The data were analysed using Cox regression models.

Setting:Copenhagen, Denmark.

Subjects:2890 men born in 1953, whose mothers were interviewed regarding family social background in 1968. The vital status of this population and their parents was ascertained from April 1968 to January 2002.

Main outcome measures:All cause mortality in study participants, their mothers, and fathers.

Results:A similar pattern of relations was found between parental social position and all cause mortality in adult life in the three triads of father, mother, and offspring constituted of the cohort of men born in 1953, their parents, and grandparents. The educational status of mothers showed no independent effect on total mortality when father’s occupational social class was included in the model in either of the triads. Low material wealth was the indicator that remained significantly associated with adult all cause mortality in a model also including parental social position and the intellectual climate of the family in 1968. In the men born in 1953 the influence of material wealth was strongest for deaths later in adult life.

Conclusion:Father’s occupational social class is associated with adult mortality in all members of the mother-father-offspring triad. Material wealth seems to be an explanatory factor for this association.
POLARIZATION OF TAU LEPTONS PRODUCED IN QUASIELASTIC NEUTRINO–NUCLEON SCATTERING
Authors: KUZMIN KONSTANTIN S. , LYUBUSHKIN VLADIMIR V. , NAUMOV VADIM A.
Published: December 2004

A numerical analysis of the polarization vector of τ's produced through quasielastic ντ and [Formula: see text] interactions with nucleons is given with two models for vector electromagnetic form factors of proton and neutron. The impact of G parity violating axial and vector second-class currents is investigated by applying a simple heuristic model for the induced scalar and tensor form factors.
BF AND ANTI-BF THEORIES IN THE GENERALIZED CONNECTION FORMALISM
Authors: AIDAOUI A. , DOEBNER H.-D. , TAHIRI M.
Published: December 2004

We present a generalized connection formalism to explicitly determine an off-shell BRST–anti-BRST algebra for BF theories. This results in the construction of anti-BF theories based on an anti-BRST exact quantum action. These are not fundamentally different from BF theories, since they are in complete duality with respect to a mirror symmetry of the ghost numbers.
A POSSIBLE GATEWAY TO ηb: χb0(2P)→ηηb
Authors: VOLOSHIN M. B.
Published: December 2004

It is argued that the branching ratio for the decay χb0(2P)→ηηb can reach few permil as a result of the enhancement of the η emission by the axial anomaly in QCD. This might make the discussed process practical for an experimental search for the ηb.
COSMIC STRING SPACETIME IN DILATON GRAVITY AND FLAT ROTATION CURVES
Authors: LEE TAE HOON
Published: December 2004

In dilaton gravity theories, we consider a string-like topological defect formed during U (1) gauge symmetry-breaking phase transition in the early Universe, and far from the cosmic string we have vacuum solutions of the generalized Einstein equation. We discuss how they can be related to the flatness of galactic rotation curves.
MOVING BREATHERS IN BENT DNA WITH REALISTIC PARAMETERS
Authors: CUEVAS J. , STARIKOV E. B. , ARCHILLA J. F. R. , HENNIG D.
Published: December 2004

Recent papers have considered moving breathers (MB) in DNA models including long range interaction due to the dipole moments of the hydrogen bonds. We have recalculated the value of the charge transfer when hydrogen bonds stretch using quantum chemical methods which takes into account the whole nucleoside pairs. We explore the consequences of this value on the properties of MBs, including the range of frequencies for which they exist and their effective masses. They are able to travel through bending points with fairly large curvatures, provided that their kinetic energy is larger than a minimum energy which depends on the curvature. These energies and the corresponding velocities are also calculated in function of the curvature.
EXTREME VALUE SEARCHING IN UNSORTED DATABASES BASED ON QUANTUM COMPUTING
Authors: IMRE SÁNDOR
Published: December 2004

Finding the extreme value of a database or a function plays an important role in computing and communication applications. Unfortunately, classical solutions suffer from computational complexity if the database is unsorted or, equivalently, the function has many local minimum/maximum points. Proposed quantum computing based solutions can guarantee success only in terms of the expected value of the database queries. In this paper we introduce a new technique exploiting the parallel processing capabilities of quantum computing in a different way. We derive quantum existence testing which allows adapting the classical logarithmic search algorithm suitable for structured databases to unstructured ones while maintaining its efficiency.
LEARNING TO ACT FROM OBSERVATION AND PRACTICE
Authors: BENTIVEGNA DARRIN C. , ATKESON CHRISTOPHER G. , UDE ALEŠ , CHENG GORDON
Published: December 2004

We present a method for humanoid robots to quickly learn new dynamic tasks from observing others and from practice. Ways in which the robot can adapt to initial and also changing conditions are described. Agents are given domain knowledge in the form of task primitives. A key element of our approach is to break learning problems up into as many simple learning problems as possible. We present a case study of a humanoid robot learning to play air hockey.
ON THE REPRESENTATION, LEARNING AND TRANSFER OF SPATIO-TEMPORAL MOVEMENT CHARACTERISTICS
Authors: ILG WINFRIED , BAKIR GÖKHAN H. , MEZGER JOHANNES , GIESE MARTIN A.
Published: December 2004

In this paper we present a learning-based approach for the modeling of complex movement sequences. Based on the method of Spatio-Temporal Morphable Models (STMMs) we derive a hierarchical algorithm that, in a first step, identifies automatically movement elements in movement sequences based on a coarse spatio-temporal description, and in a second step models these movement primitives by approximation through linear combinations of learned example movement trajectories. We describe the different steps of the algorithm and show how it can be applied for modeling and synthesis of complex sequences of human movements that contain movement elements with a variable style. The proposed method is demonstrated on different applications of movement representation relevant for imitation learning of movement styles in humanoid robotics.
THE DETERMINATION OF THE UNKNOWN THERMAL PROPERTIES OF HOMOGENEOUS HEAT CONDUCTORS
Authors: LESNIC D.
Published: December 2004

The aim of this paper is to determine the two constant parameters corresponding to the physical properties of a homogeneous heat conductor, namely, the heat capacity and the thermal conductivity, from heat flux and temperature measurements. An iterative nonlinear least-squares boundary element method is proposed. The inversion is performed for both exact and noisy measurements. Numerically, it is shown that the thermal properties can uniquely and stably be retrieved from two measurements containing at least one heat flux measurement for finite homogeneous heat conductors, whilst theoretically, for the semi-infinite conductor it is shown that one heat flux and one internal temperature measurement are necessary and sufficient.
DISCRETE COMPRESSIVE SOLUTIONS OF SCALAR CONSERVATION LAWS
Authors: DESPRÉS BRUNO
Published: December 2004

We prove the convergence of numerical approximations of compressive solutions for scalar conservation laws with convex flux. This new proof of convergence is fully discrete and does not use Kuznetsov's approach. We recover the well-known rate of convergence in O(Δx½). With the same fully discrete approach, we also prove a rate of convergence in O(Δx) uniformly in time, if the initial data is a shock, or asymptotically after the compression of the initial profile. Numerical experiments confirm the theoretical analysis.
SUSTAINABLE DEVELOPMENT EVALUATIONS IN EUROPE — MARKET ANALYSIS, META EVALUATION AND FUTURE CHALLENGES
Authors: MARTINUZZI ANDRÉ
Published: December 2004

In May 2002 and 2003, two EuroConferences on "Evaluation of Sustainability" took place in Vienna. The key objectives of the two conferences were to support an international and interdisciplinary exchange of experience, to provide training opportunities to young researchers and to build capacities for evaluations in the context of sustainable development. In the course of the series young researchers carried out country surveys, analysing the state of Sustainable Development (SD) Evaluations in their home countries. In addition, a meta-evaluation of 106 evaluation reports analysed the extent to which evaluation standards are considered. Based on the surveys conducted in 10 countries by young researchers and the findings of the meta-evaluation, the article provides a market analysis, showing the fields of application in which SD-evaluations are conducted and which driving forces may lead to a better institutionalisation of SD-evaluations. Based on the presentations and discussions at the two conferences, future research questions and policy recommendations are identified. A new "Governance by Evaluation" policy style is outlined as a concluding recommendation.
GUEST EDITORIAL: EVALUATION OF REGIONAL SUSTAINABLE DEVELOPMENT — MAPPING THE LANDSCAPE
Authors: RAVETZ JOE
Published: December 2004

This editorial introduction takes an overview of the policy and technical context for evaluation methods and tools, as applied to regional sustainable development (RSD). The papers are drawn from the European expert workshop of the REGIONET Thematic Network project. The papers were grouped into four themes to reflect the structure of the workshop: current practice; technical tools; social processes; and integrated frameworks. Each of these demonstrates different aspects of the current "landscape" of evaluation in theory and practice, and the future developments in prospect. One emerging theme is the tension between a policy orientation and a technical orientation, and the many current experiments on this interface.