bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of the Clay Fraction (<2 µm) of the Clay Minerals Society Reference Clays
Authors: Vogt Christoph , Lauterjung Jörn , Fischer Reinhard X.
Published: February 2003

We studied a set of 15 reference clays from The Clay Minerals Society (CMS) Source Clays repository. Our aim was to use them as reference materials in our version of the QUAX mineral database. The QUAX software (Quantitative Phase-Analysis with X-ray Powder Diffraction) has been used successfully at the KTB site (German Continental Deep Drillling) to determine mineral assemblages quickly, in an automatic fashion, on a large number of samples (∼40,000). It was also applied to Quaternary marine sediments of the Japan Sea. Our current research focuses on marine and lacrustrine sediments from the Arctic Ocean and Siberia.

QUAX is a full-pattern method using a reference materials database. The quality of a particular quantification depends on the availability of the relevant mineral phases in the database. Our aim is to extend and improve the database continuously with new data from our current projects, particularly from clay and feldspar minerals.

A reference material in the QUAX software must be monomineralic. Before X-ray diffraction (XRD) patterns of CMS clays could be added to the database, quantification of any impurities was necessary. After measuring the bulk material by XRD, the <2 µm fraction was separated because we assumed it would contain the smallest amount of impurities. Here we present grain-size data, XRD data and X-ray fluorescence (XRF) data for this clay-sized fraction. The results of chemical and mineralogical preparation techniques and (elemental) analysis methods were combined. For XRD, random and oriented clay-aggregate samples as well as pressed pellets for QUAX analysis were prepared. Semi-quantitative clay mineral determinations were run for comparison.
Adsorption of Dinitrophenol Herbicides From Water by Montmorillonites
Authors: Sheng Guangyao , Johnston Cliff T. , Teppen Brian J. , Boyd Stephen A.
Published: February 2003

The adsorption of two dinitrophenol herbicides, 4,6-dinitro-o-cresol (DNOC) and 4,6-dinitro-o-sec-butyl phenol (dinoseb), by two reference smectite clays (SWy-2 and SAz-1) was evaluated using a combination of sorption isotherms, Fourier transformation infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and molecular dynamic simulations. Clays were subject to saturation with various cations, and charge reduction. The DNOC adsorption decreased with increasing pH indicating that DNOC was primarily adsorbed as the neutral species. The FTIR spectra of DNOC-clay films showed that DNOC molecules are oriented parallel to the clay surface. Interlayer cations have a strong effect on adsorption depending largely on their hydration energies. Weakly hydrated cations, e.g. K+ and Cs+, resulted in greater sorption compared to more strongly hydrated cations such as Na+ or Ca2+. Lower hydration favors direct interactions of exchangeable cations with -NO2 groups of DNOC and manifests optimal interlayer spacings for adsorption. In the presence of sorbed DNOC, an interlayer spacing for K-SWy-2 of between 12 and 12.5 Å was maintained regardless of the presence of water. This d-spacing allowed DNOC molecules to interact simultaneously with the opposing clay layers thus minimizing contact of DNOC with water. The charge density of clays also affected sorption by controlling the size of adsorption domains. Accordingly, DNOC adsorption by low-charge clay (K-SWy-2) was much higher than by high-charge clay (K-SAz-1) and Li-charge reduction greatly enhanced dinoseb adsorption by K-SAz-1. Steric constraints were also evident from the observation that adsorption of DNOC, which contains a methyl substituent, was much greater than dinoseb, which contains a bulkier isobutyl group. Adsorption of DNOC by K-SAz-1 was not affected in the presence of dinoseb, whereas dinoseb adsorption was greatly reduced in the presence of DNOC.
On the Structural Stability of Montmorillonite Submitted to Heavy γ-Irradiation
Authors: Negron Alicia , Ramos Sergio , Blumenfeld Alexander L. , Pacheco Graciela , Fripiat Jose J.
Published: February 2003

The effect of heavy doses (up to 200 Mrad) of γ-radiation on the short-range structural organization in montmorillonite was studied using infrared (IR) spectroscopy and solid-state high-resolution 27Al and 29Si nuclear magnetic resonance (NMR). No change attributable to irradiation was observed. A small variation in the water content was noted but it is not systematic. The results show that the montmorillonite structure can accumulate high doses of radiation without damage and therefore this clay is a suitable material for use in the safe disposal of radioactive waste.
Tobelitization of Smectite During Oil Generation in Oil-Source Shales. Application to North Sea Illite-Tobelite-Smectite-Vermiculite
Authors: Drits Victor A. , Lindgreen Holger , Sakharov Boris A. , Jakobsen Hans Jørgen , Salyn Alfred L. , Dainyak Lidia G.
Published: February 2003

Illite-smectite (I-S) minerals isolated from Upper Jurassic oil-source rock shales from Denmark and the North Sea have been investigated by X-ray diffraction, thermal analysis, infrared, Mössbauer, and solid-state nuclear magnetic resonance spectroscopies and chemical analysis. Detailed structures have been determined in order to reveal the diagenetic transformation mechanism in these shales. Generally, in oil-source rocks of sedimentary basins, oil generation takes place simultaneously with the diagenetic transformation of I-S. We demonstrate a link between the two reactions: NH3 released from kerogen during maximum oil generation is fixed as NH4+ in the NH4-bearing mica or tobelite layers formed from smectite or vermiculite layers in I-S, in a diagenetic interval which we name the ‘tobelitization window’. Due to this solid-state transformation, mixed-layer structures have been formed consisting of interstratified illite, tobelite, smectite and vermiculite layers (I-T-S-V) and having maximum ordering of illite + tobelite and smectite layers for R = 1. The tobelitization of smectite in I-S is probably typical for all oil-source rock shales.
Methods of Determining Cation Exchange Capacities for Clinoptilolite-Rich Rocks of the Logudoro Region in Northern Sardinia, Italy
Authors: Cerri Guido , Langella Alessio , Pansini Michele , Cappelletti Piergiulio
Published: February 2003

Clinoptilolite-rich materials from widespread pyroclastic and epiclastic deposits of northern Sardinia were investigated to assess their cation exchange properties and to find the most reliable experimental method to determine their cation exchange capacity (CEC). The CECs were evaluated using a cross exchange method (CEM) and a batch exchange method (BEM). The CEM resulted in values 30–35% lower than the theoretical or expected CEC calculated from the chemical analyses of the clinoptilolite-rich materials. The BEM resulted in CECs 6–12% lower than the expected CECs. Various parameters, such as the grain-size of powders (<64 µm and 125–250 µm) and replacement cation (Na+, K+, Li+, Cs+, NH4+, Ca2+, Mg2+, Sr2+) were evaluated in order to optimize the cation exchange process, i.e. enhance complete exchange. The particle size did not affect the exchange process appreciably. The type of replacement cation had a substantial effect on the experimental CEC determined by the BEM. The NH4+ and Cs+ replacement solutions resulted in the best experimental CECs ranging between 75% and 94% of the theoretical CEC with NH4+ as the replacement cation and 79% and 88% of the theoretical CEC with Cs+ as the replacement cation. The exchange efficiency was also measured as a function of ammonium concentration in the replacement solution (0.50, 1.00, 2.00 and 3.00 M). Experimental CECs ranged between 94% (0.5 M NH4Cl solution) and 99% (1 M NH4Cl solution) of the theoretical CEC for one epiclastic rock sample and between 79% (3 M NH4Cl solution) and 87% (2 M NH4Cl solution) of the theoretical CEC for one pyroclastic rock sample.
Crystal Chemistry of Fe-Sudoites From Uranium Deposits in the Athabasca Basin (Saskatchewan, Canada)
Authors: Billault Valérie , Beaufort Daniel , Patrier Patricia , Petit Sabine
Published: February 2003

Sudoites exhibit different crystal-chemical and textural properties which may be related to the structural and valence state of Fe. Mössbauer spectroscopic analysis shows that all Fe previously analyzed using a microprobe (from 1 wt.% to 7.2 wt.% total Fe as Fe2O3) is structural and occurs in both oxidation states (40% Fe2+and ∼60% Fe3+). Electron microprobe analyses from ∼200 sudoites indicate that Fe occurs in both octahedral sheets according to three main types of substitution: Fe3+= octahedral Al; Fe2+= Mg; and Fe3++ Fe2++ □ = 3Mg. Decreasing tetrahedral substitution balances Fe3+substitution in the trioctahedral sheet. Increasing octahedral Fe results in a more dioctahedral character of sudoite.

X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, differential thermal analysis (DTA) and scanning electron microscope-transmission electron microscope (SEM-TEM) analyses showed that increasing octahedral Fe is associated with decreased stacking order and thermal stability due to the greater number of defects. In addition, with increasing octahedral Fe in sudoite, particles became smaller and more anhedral and consequently less stable with increasing Fe content. These structural and textural variations are interpreted as a result of the distortion of the sudoite structure by substitutions of Fe3+with larger ionic radii for Al and Mg octahedral cations and by the formation of octahedral vacancies.
Microbiotic Formation of Silicate Minerals in the Weathering Environment of a Pyroclastic Deposit
Authors: Kawano Motoharu , Tomita Katsutoshi
Published: February 2003

Bacterial mineralization in weathered pyroclastic deposits of the Kaimondake volcanic ash (4040 ybp) and the Koya pyroclastic flow (6400 ybp) was investigated to evaluate the impacts of bacteria on mineral formation, and to characterize the microbiogenic minerals in the weathering environment. The mineralogy of abiogenic weathering products was also investigated for comparison with the microbiogenic products, and mineral saturation indices were calculated for porewaters using the PHREEQC computer code. The results indicated that these weathered pyroclastic deposits contain 108–109 cells/g, consisting of spherical to rod-shaped bacteria. Associated abiogenic allophane had an Al/Si ratio ranging from 1.01 to 2.13. The bacterial cell surfaces were completely or partially covered by poorly-ordered silicate minerals, which could be divided into two groups based on their chemical and morphological characteristics. Group I was characterized by well developed fibrous to smectite-like flaky habits with variable Al, Si and Fe, corresponding to compositions between proto-imogolite allophane and chamosite. These Al-Si-Fe minerals were the most abundant and major microbiogenic products in both lithologies. Group II exhibited poorly-developed aggregates of allophane-like granular materials composed mainly of Al and Si with minor Fe. Geochemical calculations revealed that the porewaters were saturated with respect to allophane and other crystalline clay minerals such as halloysite, kaolinite, montmorillonite and nontronite. These microbiogenic minerals may be formed as the earliest phase of these clay minerals after interaction of the bacterial cell surfaces with dissolved cations mainly Si, Al and Fe, in the porewaters.
Significance of the Formation of Calcium Carbonate Minerals in the Pedogenesis and Management of Cracking Clay Soils (Vertisols) of India
Authors: Srivastava Pankaj , Bhattacharyya Tapas , Pal Dilip Kumar
Published: February 2003

Micromorphological studies were performed in order to understand the factors and processes involved in the formation of calcium carbonate (CaCO3) in twenty three soil series of Vertisols representing sub-humid, semi-arid and arid climatic regions of Peninsular India. The study indicates that Vertisols contain both pedogenic calcium carbonate (PC) and non-pedogenic calcium carbonate (NPC) irrespective of the ecosystems to which they belong. The NPCs are part of the parent material of Vertisols. Dissolution of NPCs and recrystallization of dissolved Ca2+ ions are responsible for the formation of PCs. Vertisols of arid and semi-arid climates contain more PC in their soil control section (SCS) than those of sub-humid climates. Formation of PC is the prime chemical reaction responsible for the increase in pH, the decrease in the Ca/Mg ratio of exchange site with depth and in the development of subsoil sodicity. Petrographic and scanning electron microscopic (SEM) examination of quartz, feldspars and micas indicate little or no alteration, discounting the possibile formation of smectite during Vertisol formation. X-ray diffraction (XRD) analysis of clays indicates that smectites of Vertisols are fairly well crystallized and do not show any sign of transformation except for hydroxy interlayering. The preservation of the crystallinity of smectite and the lack of transformation of primary minerals thus validate the hypothesis of positive entropy change during the formation of Vertisols.

The precise cause-effect relationship between CaCO3 of pedogenic and non-pedogenic origin, and exchangeable Mg, Na and Ca percentages (EMP, ESP and ECP) has been established in the study. This indicates that impoverishment of Ca2+ ions on the exchange sites of Vertisols needs to be controlled by rehabilitation methods that can replenish Ca2+ ions, and thus the study provides relevant information for future land resource management programmes not only on Vertisols of India but also on similar soils occurring elsewhere.
Influence of Gibbsite Surface Area and Citrate on Ni Sorption Mechanisms at pH 7.5
Authors: Yamaguchi Noriko U. , Scheinost Andreas C. , Sparks Donald L.
Published: February 2003

We investigated the sorption of Ni to gibbsite of two different surface areas at pH 7.5, in the presence and absence of citrate, over a time period of 180 days. Extended X-ray absorption fine-structure spectroscopy was employed to elucidate the sorption mechanisms at the molecular level. In agreement with former results, Ni-Al layered double hydroxide (LDH) formed in the presence of gibbsite of low surface area. However, gibbsite of high surface area suppressed the formation of the surface precipitate. Instead, two Al atoms neighboring Ni at distances of 2.95–2.98 Å indicated formation of an inner-sphere sorption complex, where each NiO6-octahedron shares edges with two AlO6-octahedra. Focused multiple scattering arising from Al atoms at a distance of 6 Å suggest that sorbed Ni(OH)2(OH2)4 monomers epitaxially extend the hexagonal arrangement of Al atoms in gibbsite. Only after 30 days or more was a small amount of LDH formed. The presence of citrate prevented the formation of LDH, while maintaining the formation of inner-sphere sorption complexes.
Effect of Acid and Alkali Treatments on Surface Areas and Adsorption Energies of Selected Minerals
Authors: Jozefaciuk Grzegorz , Bowanko Grzegorz
Published: February 2003

Bentonite, biotite, illite, kaolin, vermiculite and zeolite were acidified or alkalized with hydrochloric acid or sodium hydroxide at concentrations of 0.1, 1.0 and 5.0 mole dm−3 at room temperature for two weeks. In acid treatments, dissolution of Al prevailed over Si and the opposite was observed in alkali treatments. The XRD patterns showed severe alteration of the crystal structure after acid treatments, whereas sharpening of the XRD peaks after alkali treatments was observed. Illite and kaolin were most resistant to acid attack. with a few exceptions, the surface areas of the minerals computed from both water and nitrogen adsorption isotherms increased with acid and alkali treatments. with increasing reagent concentration, the nitrogen surface area increased faster than the water surface area. well-defined trends were not noted in either changes of average water or nitrogen adsorption energies or in relative amounts of adsorption sites, indicating that the effects of acid and alkali attack are controlled by the individual character of the minerals.
Emanation Thermal Analysis of Natural and Chemically-Modified Vermiculite
Authors: Poyato J. , Pérez-Maqueda L. A. , Justo A. , Balek V.
Published: February 2003

Emanation thermal analysis (ETA), based on radon release measurements from previously labeled samples, was used for the first time in the characterization of the thermal behavior of natural Mg2+-vermiculite (Santa Olalla, Huelva, Spain) and of Na+- and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:c="http://cambridge.org/core/content" xmlns:core="http://cambridge.org/core" xmlns:m="http://cambridge.org/core/metadata" xmlns:cup="http://contentservices.cambridge.org" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:mnf="http://cambridge.org/core/manifest">NH4+-exchanged vermiculite samples. In addition, vermiculite samples subjected to a chemical treatment with an aqueous solution of (NH4)2SiF6 and partially or totally re-saturated with Na+ ions were also investigated by ETA. The ETA results of natural Mg2+-vermiculite, Na+-vermiculite and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:c="http://cambridge.org/core/content" xmlns:core="http://cambridge.org/core" xmlns:m="http://cambridge.org/core/metadata" xmlns:cup="http://contentservices.cambridge.org" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:mnf="http://cambridge.org/core/manifest">NH4+-vermiculite gave supplementary information about microstructure changes of the samples observed under dynamic heating conditions. The method has proved to be very useful for characterization of microstructure changes due to modification in the interlayer space of samples during the heat treatment. The crystallization of vermiculite into new phases, such as enstatite (for <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:c="http://cambridge.org/core/content" xmlns:core="http://cambridge.org/core" xmlns:m="http://cambridge.org/core/metadata" xmlns:cup="http://contentservices.cambridge.org" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:mnf="http://cambridge.org/core/manifest">NH4+-vermiculite and Mg2+-vermiculite) and forsterite (for Na+-vermiculite) was also observed by ETA.
Preparation and Characterization of Eu-Magadiite Intercalation Compounds
Authors: Mizukami Naoko , Tsujimura Masashi , Kuroda Kazuyuki , Ogawa Makoto
Published: February 2003

The intercalation of europium ions (Eu3+) into the interlayer space of a layered silicate, magadiite, was conducted by ion-exchange reactions between magadiite and europium(III) chloride. X-ray diffraction and elemental analysis results indicated that Eu3+ cations were intercalated into the interlayer space of magadiite. The ion exchange between Eu3+ and Na+ occurred preferentially so that the adsorbed Eu3+ amounts were controlled quantitatively. Thermal transformation of the original layered structure was suppressed by the intercalation of Eu3+. The resulting intercalation compounds exhibited photoluminescence arising from the intercalated Eu3+. The luminescence intensity varied in accordance with the amount of Eu3+ absorbed, suggesting that the self-quenching occurred at higher loading levels. The luminescence intensity was also changed by the heat treatment, corresponding to the change in the surroundings of the Eu3+ adsorbed, induced by the removal of the adsorbed water molecules and the hydroxyl groups of the silicate.
Diagnosis of fetal acrania during the first trimester nuchal translucency screening for Down syndrome
Authors: Cheng C.‐C. , Lee F.‐K. , Lin H.‐W. , Shih J.‐C. , Tsai M.‐S.
Published: February 2003

Objectives: Prenatal screening during the first‐trimester using fetal nuchal translucency (NT) measurement and maternal serum levels of free β‐human chorionic gonadotropin (hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) has become an established method for the detection of fetal Down syndrome. Increasing evidence has shown that some of the fetal structural abnormalities could be identified during NT scanning. Second trimester maternal serum alpha‐fetoprotein (MSAFP) measurements and ultrasound scans have been widely used in clinical practice to identify fetal neural tube defects (NTDs). In this study, we evaluated the effectiveness of early diagnosis of fetal acrania during NT scanning. Methods: We reviewed the medical records of 5890 pregnancies that were delivered in our hospital between January 1, 1999 and January 31, 2001. Among them, 3600 pregnant women received NT‐based Down syndrome screening at 10–13 weeks’ gestation. Pregnancies with fetal NTDs were evaluated and their maternal serum levels of free β‐hCG and PAPP‐A were compared with those of the normal control pregnancies. Results: Seven of the 3600 pregnancies were identified with fetal acrania and all of them were detected during first‐trimester NT scanning. Among the seven cases, five had measurements of maternal serum concentration free β‐hCG and PAPP‐A concentration, yet there were not significant difference between the pregnancies with fetal acrania and those of the control pregnancies (PAPP‐A, 1.13 vs. 0.96; free β‐hCG, 1.10 vs. 1.06; P>0.05). Two of the seven affected patients did not have maternal serum biochemical measurements due to the immediate termination of pregnancies. Conclusions: We demonstrated that pregnancies with fetal acrania could be easily identified at the time of NT scanning. Careful ultrasound inspection of fetal structure during NT measurements at 10–13 weeks of gestation provides an encouraging advantage for early diagnosis of fetal acrania.
Calcium–phosphorus–magnesium homeostasis in pregnant women after renal transplantation
Authors: Czajkowski K. , Wójcicka‐Bentyn J. , Grymowicz M. , Smolarczyk R. , Malinowska‐Polubiec A. , Romejko E.
Published: February 2003

Objective: The aim of the study was the assessment of calcium–phosphorus–magnesium homeostasis in pregnant women after renal transplantation. Methods: The study covered 64 pregnant women in the third trimester of gestation including: 33 women after renal transplantation (the study group) and 31 healthy pregnant women (the control group). Women from both groups were at the similar age: 30.8±4.7 vs. 31.3±5.0 years (NS) and at the same gestational age 34.8±2.4 vs. 35.3±2.6 weeks (NS). The mean body mass index (BMI) in the women from the study group before pregnancy was 21.49±2.81 vs. 22.1±3.02 in the control group (NS), BMI before delivery was 25.43±3.05 vs. 26.0±3.35 (NS), the percentage of the BMI increase during pregnancy was 18.7±7.68 vs. 17.65±7.13 (NS) and BMI increase during gestation was 3.93±1.56 vs. 3.90±1.54, respectively (NS). Arterial blood pressure at the time of blood samples collection for biochemical tests was 151.4±26.8/92.5±16.9 in women from the study group comparing to 115.0±6.0/68.0±7.0 mmHg (P<0.001) in the patients from the control group. The maximal blood pressure during pregnancy was 169.2±20.7/102.7±14.0 vs. 118.0±7.0/70.0±8.0 mmHg (P<0.001), respectively. We estimated serum levels of: total Ca, ionized Ca2+, inorganic phosphorus (Pi), Mg, total protein, albumin and blood morphology. Moreover, urine levels of Ca, Pi, Mg and protein were assessed. Results: The pregnant women after renal transplantation presented increases in serum concentrations of total Ca (2.54±0.20 vs. 2.16±0.10 mmol/l; P<0.001) and ionized Ca2+ (1.322±0.104 vs. 1.12±0.07 mmol/l; P<0.001) and the decrease in Pi level (1.013±0.211 vs. 1.10±0.16 mmol/l; P<0.05), total protein (59.3±7.0 vs. 65±5 g/l; P<0.001) and albumin (461.6±65.65 vs. 493.2±59 μmol/l; P<0.05). Moreover, in the study group drop in red blood cells count to 3.71±0.56 vs. 4.01±0.35×1012/l (P<0.02) in the control group was detected. Despite increased volume of 24‐h urine collection in the kidney recipients we observed significantly decreased urine 24‐h calcium excretion 2.47±0.92 vs. 6.72±3.49 mmol (P<0.001) and simultaneous increase in urine Mg excretion 3.422±1.025 vs. 2.18±0.52 mmol/24 h (P<0.001). There was no difference in urine 24‐h Pi excretion between the study and the control group. The pregnant renal transplant recipients presented proteinuria of 1.19±1.9 g/24 h. Conclusions: Women after kidney grafting present vital aberrations in calcium–phosphorus–magnesium homeostasis during pregnancy. The most significant changes are associated with calcium metabolism (high increase in serum Ca levels and impairment of renal elimination of calcium). The observed changes may be influenced by the doses of immunosuppressive agents and disturbed renal function.
Comparison of fennel and mefenamic acid for the treatment of primary dysmenorrhea
Authors: Namavar Jahromi B. , Tartifizadeh A. , Khabnadideh S.
Published: February 2003

Objectives: To compare the effect of Foeniculum vulgare variety dulce (Sweet Fennel) vs. mefenamic acid for the treatment of primary dysmenorrhea. Methods: A cohort of seventy women, 15–24 years old from a local university and high‐school, who complained of dysmenorrhea were enrolled in this study. Ten cases were excluded due to evidence of secondary dysmenorrhea. The remaining 60 patients were graded mild, moderate and severe on the basis of a verbal multidimensional scoring system. Thirty patients with mild dysmenorrhea were also excluded from the study. Each of the 30 cases with moderate to severe dysmenorrhea was evaluated for three cycles. In the first cycle no medication was given (control cycle), in the second cycle the cases were treated by mefenamic acid (250 mg q6h orally) and in the third cycle, essence of Fennel's fruit with 2% concentration (25 drops q4h orally), was prescribed at the beginning of the cycle. These cycles were compared day by day for the effect, potency, time of initiation of action and also complications associated with each treatment modality, by using a self‐scoring system. Intensity of pain was reported by using a 10‐point linear analog technique. Statistical analyses were performed by the independent sample t‐test, paired t‐test and repeated measurement analysis method. Results: In the study group the mean age of menarche was 12.5±1.3 years, the mean duration of menstruation was 6.6±1.4 days with the mean cycle days of 27±3. The findings observed during menses were as follows: headache in 26.7%, nausea in 63.3%, vomiting in 23.3%, diarrhea in 33.3%, fatigue in 93.3% and leaving the daily tasks undone was reported in 86.9% of the cases. Both of the drugs effectively relieved menstrual pain as compared with the control cycles (P<0.001). The mean duration of initiation of action was 67.5±46.06 min for mefenamic acid and 75±48.9 min for fennel. The difference was not statistically significant (P=0.57). Mefenamic acid had a more potent effect than fennel on the second and third menstrual days (P<0.05), however, the difference on the other days was not significant. No complication was reported in mefenamic acid treated cycles, but five cases (16.6%) withdrew from the study due to fennel's odor and one case (3.11%) reported a mild increase in the amount of her menstrual flow. Conclusions: The essence of fennel can be used as a safe and effective herbal drug for primary dysmenorrhea, however, it may have a lower potency than mefenamic acid in the dosages used for this study.
Autotransfusion for ruptured ectopic pregnancy
Authors: Selo‐Ojeme D.O , Onwude J.L , Onwudiegwu U
Published: February 2003

Objectives: Clinical outcomes following the exclusive use of autotransfusion in the management of ruptured ectopic pregnancy are reviewed. Methods: A MEDLINE search (1966–2002) for relevant articles documenting the exclusive use of autotransfusion, and data collection and analysis was made. Results: There were 21 studies, 16 from developing and five from developed countries, involving 632 cases of ruptured ectopic pregnancies. Hypovolemic shock with significant hemoperitoneum (>500 ml) was the most common complication. The procedure was performed completely manually in developing countries and with the help of a device in developed countries. The mean volume of autotransfused blood was over 1000 ml, with mean hemoglobin levels ranging from 6 to 12.5 g/dl. Mean posttransfusion hemoglobin levels were higher than pretransfusion levels. There was one death, thought to be due to pulmonary embolism, and nine major and minor complications. Conclusions: Autotransfusion is useful in the management of ruptured ectopic pregnancy.
Parametrial tumor spreading patterns in cervix cancer patients treated by radical hysterectomy
Authors: Yen M.‐S. , Yuan C.‐C. , Wang P.‐H. , Ng H.‐T. , Twu N.‐F. , Juang C.‐M.
Published: February 2003

Objectives: To evaluate tumor‐spreading patterns in the parametrium. Methods: We conducted a prospective clinical trial between January 1998 and December 2000 to define a new method for parametrium evaluation. The parametrium was divided into three areas, paracorpus, paracervix, and paravagina. A total of 284 consecutive patients with FIGO stage IB to IIA cervical cancer who had undergone radical hysterectomy were considered for the study. Results: Of the 262 patients who were found eligible for evaluation, 135 had histopathologic analysis performed according to the new method and 127 with the traditional method. The detection of rate of parametrial invasion was 36 (26.7%) with the new and 13 (10.2%) with the traditional method (P=0.0014). The frequency of pelvic lymph node metastasis was 66.7% in patients who had tested positive for invasion of the paracorpus, 57.7% in those who had tested positive for invasion of the paracervix, and 71.4% in those who had tested positive for invasion of the paravagina. The frequency of pelvic lymph node metastasis in patients who had tested negative for invasion of the paracorpus, paracervix, or paravagina was 4.0%. Tumor cells tend to spread laterally and inferiorly in the parametrium. Conclusions: Using our classification of three parametrium areas for histologic examination can increase the detection rates of parametrial tumor invasion and help prevent failure of local treatment by allowing to implement appropriate adjuvant therapy.
Factors influencing the quality of life of infertile women in United Arab Emirates
Authors: Khayata G.M. , Rizk D.E.E. , Hasan M.Y. , Ghazal‐Aswad S. , Asaad M.A.N.
Published: February 2003

Objectives: To measure the quality of life in a representative sample of infertile women and evaluate their sociocultural attitude to this condition. Methods: Two hundred sixty‐nine infertile women attending the Assisted Reproduction clinic, Tawam Hospital were consecutively selected. They were interviewed about the effect of infertility on their quality of life using a structured, measurement‐specific and pre‐tested questionnaire. Results: Parameters mostly affected were mood‐related mainly in women above 30 years, with primary and female factor infertility and those in polygamous marriages. Quality of life did not affect sexual performance and was not affected by duration of infertility or cost of treatment. Conclusion: The results highlight the importance of bearing children and the stresses exerted on infertile women in Eastern societies. Thorough counseling and continuing support of infertile women is therefore indicated to improve their quality of life.
Attitudes of Singapore women toward cesarean and vaginal deliveries
Authors: Chong E.S.Y. , Mongelli M.
Published: February 2003

Objectives: To assess the attitude, knowledge, and expectations of Asian pregnant women toward cesarean and vaginal deliveries. Methods: Written questionnaires were given to pregnant women attending the National University Hospital antenatal clinics, and 160 responses were tabulated and analyzed using SPSS software. Results: The participation rate was 65% and 50% of the respondents were Chinese, 20% Indian, 21% Malay, 2% White, and 9.2% Other. The median age was 31 years, and approximately 43% were primiparas. Only 3.7% of them would prefer an elective cesarean delivery, and although 50% had friends or relatives who requested one, only 3% felt that this influenced their preference. The most common reasons for choosing a cesarean delivery were avoiding labor pains and lowering the risk of fetal distress. When asked which modality they would recommend to their friends, only 2% expressed that they would recommend cesarean delivery; however, 71% stated that women should have the right to request a cesarean delivery. Awareness of complications arising from vaginal and cesarean deliveries was generally low and related to the frequency of these complications. There was no significant correlation between demographic characteristics and maternal preference for mode of delivery. Conclusions: Asian women largely prefer a vaginal delivery, and their attitude toward cesarean delivery on demand is comparable with that of Western women. Cultural or ethnic differences are unlikely to affect maternal preference for cesarean delivery in Singapore women.
Sonohysterosalpingographic screening for infertile patients
Authors: Alborzi S. , Dehbashi S. , Khodaee R.
Published: February 2003

Objectives: To compare the diagnostic accuracy of hysterosalpingography and sonohysterosalpingography in detecting tubal and uterine abnormalities. Methods: In a prospective study for the evaluation of uterine and tubal pathologies, 186 patients with primary and secondary infertility rates (51.6% and 44%, respectively), as well as recurrent abortion rates (3.8%), underwent sonohysterosalpingography. The tubal pathologies, as well as intracavitary and/or structural uterine abnormalities, detected with this procedure were compared with preoperative hysterosalpingography and operative procedures. Results: With surgical findings as the gold standard, sonohysterosalpingography had a sensitivity of 78.2%, a specificity of 93.1%, a positive predictive value of 82.7%, and a negative predictive value of 91%. For total tubal and uterine pathologies, the findings for the same parameters using HSG were 76.3%, 81.8%, 90.9%, and 59.2%, respectively. Sonohysterosalpingography was more accurate than hysterosalpingography for detecting intrauterine adhesions and various forms of uterine anomalies. Conclusions: Sonohysterosalpingography is a safe, easy, accurate, and promising procedure for the detection of female upper genital tract pathologies, especially because it can differentiate specific uterine anomalies.
Modulation of junctional communication by phosphorylation: protein phosphatases, the missing link in the chain
Authors: Hervé Jean Claude , Sarrouilhe Denis
Published: February 2003

Summry— Protein phosphorylation has been proposed to control the degree of intercellular gap junctional communication at several steps, from gene expression to protein degradation. In vertebrates, gap junctions are composed of proteins from the “connexin” (Cx) gene family, and the majority of connexins are post‐translationally modified by phosphorylation. Alterations in the phosphorylation status of proteins, resulting from the dynamic interplay of protein kinases and protein phosphatases, are thought to be involved in a broad variety of connexin processes (such as the trafficking, assembly/disassembly and degradation, as well as the gating of gap junction channels), but the underlying mechanisms remain poorly understood. Although protein kinases have an established role in this process (see Cruciani and Mikalsen, this issue), less is known about the involvement of protein phosphatases. The present review examines the role played by protein dephosphorylation catalysers in the regulation of gap junctional communication.
InsP3‐mediated calcium release induced by heterologous expression of total chicory Leaf RNA
Authors: Debarbieux‐Deleporte M. , Delbreil B. , Collin T. , Delcourt P. , Vasseur J. , Prevarskaya N. , Ouadid‐Ahidouch H.
Published: February 2003

Summry— A calcium dependent‐chloride current (Ini) was recorded in Xenopus oocytes injected with total RNA from chicory leaf tissues, following depolarization from −35 to +60 mV. However, the signal transduction mechanism mediating Ini is unknown. The development of this current was mimicked by intracellular injection of the second messenger InsP3 in control (non‐injected) oocytes. Moreover, InsP3 injection after Ini rundown did not reinitiate the current. The same phenomenon was observed following a second injection into control oocytes. Measurement of InsP3 production in injected oocytes showed a net increase in the InsP3 level on depolarization. Moreover, extracellular application of caffeine (5 mM) significantly reduced the number of oocytes displaying Ini. Also, extracellular application of U‐73122, a potent PLC inhibitor, clearly reduced the occurrence of Ini. These data provide the first evidence that the calcium homeostasis mechanism induced by heterologous expression of total RNA from chicory leaves involves the InsP3 signaling pathway.
The electrophysiology of gap junctions and gap junction channels and their mathematical modelling
Authors: Vogel Rolf , Weingart Robert
Published: February 2003

Summry— In most tissues of vertebrates, gap junctions control the exchange of ions and small molecules between adjacent cells, thus co‐ordinating the cellular activities. The application of the dual voltage‐clamp method to cell pair preparations enables one to elucidate the electrical properties of gap junctions and gap junction channels. The conductive and kinetic data obtained at the multichannel and single channel level led to a generalised concept for the operation of gap junction channels. Based on the biological data gained in this way, a mathematical model has been developed. This model is versatile and allows to simulate the electrophysiological behaviour of different types of vertebrate gap junctions.
Transforming growth factor β activates Rac1 and Cdc42Hs GTPases and the JNK pathway in skeletal muscle cells
Authors: Meriane Mayya , Charrasse Sophie , Comunale Franck , Gauthier‐Rouvière Cécile
Published: February 2003

Summry— The transforming growth factor β (TGFβ) plays an important role in cell growth and differentiation. However, the intracellular signaling pathways through which TGFβ inhibits skeletal myogenesis remain largely undefined. By measuring GTP‐loading of Rho GTPases and the organization of the F‐actin cytoskeleton and the plasma membrane, we analyzed the effect of TGFβ addition on the activity of three GTPases, Rac1, Cdc42Hs and RhoA. We report that TGFβ activates Rac1 and Cdc42Hs in skeletal muscle cells, two GTPases previously described to inhibit skeletal muscle cell differentiation whereas it inactivates RhoA, a positive regulator of myogenesis. We further show that TGFβ activates the C‐jun N‐terminal kinases (JNK) pathway in myoblastic cells through Rac1 and Cdc42Hs GTPases. We propose that the activation of Rho family proteins Rac1 and Cdc42Hs which subsequently regulate JNK activity participates in the inhibition of myogenesis by TGFβ.
Six Sigma: a goal‐theoretic perspective
Authors: Linderman Kevin , Schroeder Roger G. , Zaheer Srilata , Choo Adrian S.
Published: February 2003

Six Sigma is a phenomenon that is gaining wide acceptance in industry, but lacks a theoretical underpinning and a basis for research other than “best practice” studies. Rigorous academic research of Six Sigma requires the formulation and identification of useful theories related to the phenomenon. Accordingly, this paper develops an understanding of the Six Sigma phenomena from a goal theoretic perspective. After reviewing the goal theory literature, these concepts, when applied to Six Sigma, suggest some propositions for future research. This paper can help serve as a foundation for developing scientific knowledge about Six Sigma.
Upper critical field and location of surface nucleation of superconductivity
Authors: Helffer Bernard , Pan Xing-Bin
Published: February 2003

In this paper we improve the estimate obtained by Lu–Pan on the value of the upper critical field

H_{C_3}(κ)

for a cylindrical superconductor with cross section

Ω

being an arbitrary 2-dimensional smooth bounded domain. We also show that, when a homogeneous magnetic field is applied along the axis of the cylinder with magnitude of the field close to

H_{C_3}

, superconductivity nucleates first at the surface of the sample where the curvature of

∂Ω

is maximal.

Nous améliorons dans cet article l’estimation obtenue par Lu–Pan de la varleur du champ surcritique

H_{C_3}(κ)

pour un supraconducteur cylindrinque dont la section

Ω

est un ouvert régulier borné dans le plan.

Nous montrons aussi que, lorsqu’un champ magnétique constant parallèle à l’axe du cylindre est appliqué avec une intensité voisine de

H_{C_3}(κ)

, la supraconductivité apparaı̂t d’abord aux points du bord où la courbure

∂Ω

est maximale.
Boundary layer formation in the transition from the Porous Media Equation to a Hele–Shaw flow
Authors: Gil O. , Quirós F.
Published: February 2003

Let

u_m(x,t)

be the solution to the Porous Media Equation,

u_t=Δu^m

, in a domain

Ω⊂ ℝ^n

, with initial data

u_m(x,0)=f(x)

and boundary data

u^m_m(x,t)=g(x)

. Let

v_m≡u^m_m

. We prove the convergence as

m

goes to infinity of the pair

(u_m,v_m)

to a pair

(u_∞,v_∞)

which is a weak solution of the Hele–Shaw problem with boundary data

v_∞=g

and initial data

u_∞(x,0) = \tilde f(x)

, where

\tilde f

is the projection of the initial data

f(x)

into a ‘mesa’. We also prove the convergence of the positivity sets of the functions

u_m

to the positivity set of

u_∞

. For large but finite

m

a boundary layer connecting the initial data 

f(x)

and its projection 

\tilde f(x)

appears. We analyze the convergence of solutions and positivity sets in this boundary layer by introducing a suitable time scale. All our results hold true also for the Cauchy problem (

Ω=ℝ^n

, no boundary data).

Soit

u_m(x,t)

la solution de l’équation des milieux poreux

u_t=Δu^m

, dans un domaine

Ω⊂ℝ^n

, avec donnée initiale

u_m(x,0)=f(x)

et

u^m_m(x,t)=g(x)

fixée sur la frontière de 

Ω

. Soit

v_m≡u^m_m

. Nous montrons la convergence, lorsque l’exposant

m

va à l’infini, de la paire

(u_m,v_m)

vers

(u_∞,v_∞)

, qui est l’unique solution faible du problème de Hele–Shaw avec donnée

v_∞=g

au bord de

Ω

, et donnée initiale

u_∞(x,0) = \tilde f(x)

,

\tilde f(x)

étant la projection de

f(x)

sur une ‘mesa’. Nous prouvons aussi la convergence des ensembles de positivité des functions

u_m

vers celui de

u_∞

. Pour

m

grand, mais fini, une couche limite apparaı̂t, faisant la connexion entre la donnée initiale

f(x)

et sa projection 

\tilde f(x)

. Nous étudions la convergence des solutions et des ensembles de positivité dans cette couche limite, introduisant une échelle de temps convenable. Les résultats de ce papier contiennent également le cas du problème de Cauchy pour l’équation des milieux poreux (

Ω=ℝ^n

, aucune donnée n’est fixée sur la frontière de

Ω

).
Multi-bump ground states of the Gierer–Meinhardt system in ℝ2
Authors: del Pino Manuel , Kowalczyk Michał , Wei Juncheng
Published: February 2003

We consider the stationary Gierer–Meinhardt system in

ℝ^2

:

\begin{cases}
\Delta A - A + \frac{A^{2}}{H} = 0 & \text{in }ℝ^{2}, \\
\Delta H - \sigma ^{2}H + A^{2} = 0 & \text{in }ℝ^{2}, \\
A,H > 0;\ A,H\rightarrow 0 & \text{as }\left|x\right|\rightarrow + \infty .
\end{cases}

We construct multi-bump ground-state solutions for this system for all sufficiently small

σ

. The centers of these bumps are located at the vertices of a regular polygon, while the bumps resemble, after a suitable scaling in their

A

-coordinate, the unique radially symmetric solution of

\begin{cases}
\Delta w - w + w^{2} = 0 & \text{in }ℝ^{2}, \\
0 < w\left(y\right)\rightarrow 0 & \text{as }\left|y\right|\rightarrow \infty .
\end{cases}

A similar construction is made for vertices of two concentric polygons and a general procedure for detection of organized finite patterns is suggested.

On considère le système stationnaire de Gierer–Meinhardt dans

\begin{cases}
\Delta A - A + \frac{A^{2}}{H} = 0 & \text{dans }ℝ^{2}, \\
\Delta H - \sigma ^{2}H + A^{2} = 0 & \text{dans }ℝ^{2}, \\
A,H > 0;\ A,H\rightarrow 0 & \text{quand }\left|x\right|\rightarrow + \infty .
\end{cases}

On construit des solutions fondamentales multi-pics pour ce système, pour tout

σ

suffisamment petit. Les centres de ces pics sont localisés aux sommets d’un polygone régulier, tandis que les pics ressemblent, après un changement d’échelle approprié dans la coordonnée

A

, à l’unique solution radiale de

\begin{cases}
\Delta w - w + w^{2} = 0 & \text{dans }ℝ^{2}, \\
0 < w\left(y\right)\rightarrow 0 & \text{quand }\left|y\right|\rightarrow \infty .
\end{cases}

Une construction similaire est faite pour les sommets de deux polygones concentriques et une procédure générale de détection destructures finies organisées est suggérée.
A dissection and computer tomograph study of tarsal coalitions in 100 cadaver feet
Authors: Solomon L. B. , Rühli F. J. , Taylor J. , Ferris L. , Pope R. , Henneberg M.
Published: February 2003

Most of the clinical studies report the incidence of tarsal coalitions (TC) as less than 1% but they disregard the asymptomatic coalitions. TC have been associated with degenerative arthritic changes. After X‐rays, computer tomography (CT) is the most commonly used diagnostic test in the detection of TC.

The aims of our study were to establish the incidence of TC; the association between TC and accessory tarsal bones and between TC and tarsal arthritis; and to assess the sensitivity of CT as a diagnostic tool in TC. We performed spiral CT scans of 100 cadaver feet (mean age at death 77.7 ± 10.4), which were subsequently dissected. The dissections identified nine non‐osseous TC: two talocalcaneal and seven calcaneonavicular. There was no osseous coalition. Tarsal arthritis was identified in 31 cases. Both talocalcaneal coalitions were associated with arthritis while none of the calcaneonavicular coalitions were associated with tarsal arthritis. The CT diagnosed an osseous talocalcaneal coalition and was suspicious of fibrocartilaginous coalitions in eight cases. There was correlation between dissection and CT in two talocalcaneal coalitions and three calcaneonavicular coalitions thus CT identifying 55.5% of the coalitions. CT did not diagnose four non‐osseous coalitions and diagnosed errouresly four possible coalitions. In conclusion our study demonstrated that the incidence of non‐osseous TC is higher than previously thought (12.72%). The calcaneonavicular coalitions are the most common single type (9.09%) and they do not seem to be associated with arthritic changes in the tarsal bones. Our CT results suggest that spiral CT has a low sensitivity in the detection of non‐osseous coalitions and questions if multislice CT should be used routinely when TC are suspected.

© 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.