bluuebunny/crossref_metadata_2025 huggingface dataset:
A Culture-Bound Syndrome ‘Amafufunyana’ and a Culture-Specific Event ‘Ukuthwasa’: Differentiated by a Family History of Schizophrenia and other Psychiatric Disorders
Authors: Niehaus D.J.H. , Oosthuizen P. , Lochner C. , Emsley R.A. , Jordaan E. , Mbanga N.I. , Keyter N. , Laurent C. , Deleuze J.-F. , Stein D.J.
Published: April 2004

Background: ‘Amafufunyana’ and ‘ukuthwasa’ are two culture-specific descriptive terms used by Xhosa traditional healers to explain aberrant behavioral and psychological phenomena. Some overlap between these conditions and schizophrenia (DSM-IV) is apparent. The aim of this study was to determine the extent to which amafufunyana and ukuthwasa were used as cultural explanatory models by traditional healers for DSM-IV-defined schizophrenia and whether there were significant phenomenological differences in schizophrenia symptoms in patients with the diagnosis of amafufunyana rather than ukuthwasa. Sampling and Methods: Xhosa patients with schizophrenia underwent a structured clinical diagnostic interview (Diagnostic Interview for Genetic Studies). The use of traditional diagnostic and treatment methods was assessed by structured open-ended interviewer-rated questions. The sample was then stratified for the presence/absence of a past/current diagnosis of amafufunyana and/or ukuthwasa. The clinical parameters were compared across groups by means of the χ2 or Student t tests. Results: 247 adult subjects participated in the study. 106 (53%) patients reported a previous diagnosis of amafufunyana, and 9 (4.5%) reported a diagnosis of ukuthwasa. A family history of schizophrenia (p = 0.004) or any psychiatric disorder (p = 0.008) was more common in the ukuthwasa group. Subjects with a primary diagnosis other than amafufunyana or ukuthwasa were more likely to be married (p = 0.004), to have a history of stressor(s) prior to illness onset (p = 0.026), to be from a rural environment (p = 0.007) or to have a history of cannabis abuse/dependency (p = 0.015). Conclusion: The culture-bound syndrome amafufunyana and the culture-specific phenomenon of ukuthwasa are both used to explain symptoms in patients with schizophrenia (DSM-IV). Identification of cases as amafufunyana and ukuthwasa may correlate with a distinction between familial and sporadic cases of schizophrenia. Whether the positive connotations associated with ukuthwasa, as opposed to the more negative connotations associated with amafufunyana, hold any implications for the treatment or prognosis of schizophrenia remains to be clarified.
Stressful Life Events and Fibrinogen Level in Middle-Aged Teachers
Authors: Fenga C. , Micali E. , Cacciola A. , Trimarchi G. , Germanò D.
Published: April 2004

Background: Strong evidence has been reported that a high plasmatic level of fibrinogen plays a central role in the development of coronary heart disease. Many researches showed that stressful life events lead to an increase in plasmatic fibrinogen. The present investigation examined the relationship between plasmatic fibrinogen level and stressful life events. Sampling and Methods: A sample of 40 middle-aged women employed as teachers underwent a general objective examination, a venous puncture for plasma fibrinogen level evaluation, and completed a questionnaire regarding health behaviours, at baseline and 1-year follow-up. The stressful life events were recorded using the Paykel’s interview for recent life events. Results: At the baseline assessment, the distribution of teachers in the two stress exposure groups was 16 women for the non-exposed group of teachers, and 24 for the exposed teachers, while at the 1-year follow-up assessment, it was 10 for the non-exposed and 30 for the exposed group. The number of teachers exposed to stress was significantly higher at the 1-year follow-up than at the baseline assessment (30 and 24, respectively; p < 0.05). Average levels of plasmatic fibrinogen were significantly higher in stress-exposed women than in non-exposed women both at baseline assessment (p < 0.01) and at 1-year follow-up (p < 0.002). Moreover, the mean value of fibrinogen at the follow-up assessment showed a higher increase in stressed women compared with non-stressed women with an annual increase of 10.71 and 5.40%, respectively. Conclusions: Stress may trigger the hypercoagulable state evidenced by an increased plasmatic fibrinogen level. This mechanism may help explain the adverse impact of stress on the cardiovascular system.
Self-Centrality, Basic Symptoms Model and Psychopathology in Schizophrenia
Authors: Maggini Carlo , Raballo Andrea
Published: April 2004

The study’s aim was to empirically derive the psychopathological constellation associated with self-centrality (i.e. non-delusional self-referential attitude) by seeking an interpretation in the light of the ‘Basic Symptoms Model’ of schizophrenic psychopathology. Eighty-four patients with an established schizophrenic illness receiving maintenance treatment at the Psychiatry Section of the Parma University Neuroscience Department were examined. The Scales for the Assessment of Positive and Negative Symptoms, the Calgary Depression Scale and the Toronto Alexithymia Scale were administered to all subjects to determine levels of positive, disorganized, negative and depressive symptoms, as well as alexithymia. Subjective experiences, including non-delusional self-centrality, were explored by means of the Bonn Scale for the Assessment of Basic Symptoms. Logistic regression detected three different psychopathological domains (delusional, alexithymic, and basic body symptoms) strongly associated with self-centrality. Among these the most influential independent variable was basic body symptoms. These results suggest that impaired lived body experience (i.e. protopathic body disattunement) is a psychopathologic condition concomitant with the emergence of autocentric polarization of experience (i.e. self-centrality).
Pathological Laughter as an Obsessive-Compulsive Phenomenon
Authors: Mendhekar D.N.
Published: April 2004

Method: Pathological laughter has been known to occur in organic and functional psychotic disorders and is sometimes seen in hysteria. Though it is an important phenomenon, its significance in other psychiatric disorders has been negligible. This case report highlights the phenomenology of pathological laughter as an obsessive-compulsive phenomenon in an adolescent girl. Results: The girl was brought by her parents with a history of laughing without reason, but on detail evaluation, it was found that her laughing was an irrational and ego-dystonic phenomenon. She also showed resistance to her symptom. A family history of obsessive-compulsive disorder in the parental grandfather, the habit of smiling in her father and her childhood emotional trauma and sexual abuse could have contributed to the formation of the symptom. Selective serotonin reuptake inhibitor drugs and behavior therapy showed good improvement in this case. Discussion: Pathological laughter, though common in organic and psychotic disorders, can present primarily as an obsessive-compulsive phenomenon as well. This case suggests that each and every patient with a history of pathological laughter in a psychiatry clinic should not be labeled as psychotic unless he or she is assessed in detail.
In vivo Effect of Recombinant Human Granulocyte Colony-Stimulating Factor on Phagocytic Function and Oxidative Burst Activity in Septic Neutropenic Neonates
Authors: Ahmad Magdy , Fleit Howard B. , Golightly Marc G. , La Gamma Edmund F.
Published: April 2004

Neutrophil dysfunction may contribute to an increased risk of sepsis in very-low-birth-weight (VLBW) neonates. The current study was designed to determine whether recombinant human granulocyte colony-stimulating factor (rhG-CSF) affects absolute neutrophil count (ANC), phagocytic function, and oxidative burst in neutropenic VLBW neonates. Fourteen ventilated VLBW neonates were treated with rhG-CSF (10 µg/kg/day × 3 days i.v.). Phagocytic activity and oxidative burst were assessed before and after treatment with rhG-CSF using flow cytometry and fluorescence labeled opsonized Staphylococcus aureus. Control (nonseptic, nonneutropenic, n = 4), preeclamptic neutropenic (PET; nonseptic, n = 5), and septic neutropenic (n = 5) neonates with a gestational age ranging from 24 to 30 weeks were studied. In both PET and septic neonates, posttreatment phagocytosis more than doubled, but did not achieve matching control levels, whereas rhG-CSF treatment maintained the level of the phagocytic activity in the control group. The oxidative burst increased in all groups, but, again, PET and septic groups did not achieve matching control values. These effects occurred independent of a 2- to 12-fold increase in ANC. These results suggest that other disease-specific factors delay full functional recovery even after rhG-CSF treatment. We speculate that PET and septic neonates may remain susceptible to infection due to deficient neutrophil-killing capacity, even though their ANC returns to normal ranges. Augmenting immune function beyond the immediate period of ANC recovery suggests that prophylaxis with rhG-CSF may be an important risk reduction strategy for susceptible VLBW neonates.
Favorable Effect of Cotransfection with TGF-β and CTLA4Ig of the Donor Kidney on Allograft Survival
Authors: Tomasoni Susanna , Longaretti Lorena , Azzollini Nadia , Gagliardini Elena , Mister Marilena , Buehler Thomas , Remuzzi Giuseppe , Benigni Ariela
Published: April 2004

Background/Aims: Gene transfer of viral interleukin 10 (vIL-10) or transforming growth factor beta (TGF-β) successfully prolonged liver and heart graft survival. Here we assessed whether injection of adenovirus (Ad) coding vIL-10 (AdvIL-10) or TGF-β3 (AdTGF-β3) prolonged kidney allograft survival. Since we previously demonstrated that transfection of the donor kidney with CTLA4Ig significantly prolonged allograft survival, we also evaluated the effect of a combined injection of AdvIL-10 or AdTGF-β3 with the AdCTLA4Ig. Methods: Adenoviral vectors or saline were ex vivo injected into the renal artery of Brown Norway (RT.1n) donor kidneys subsequently grafted into Lewis (RT.1l) rats. Graft survival, transgene expression, graft cell infiltration, and histological changes were assessed. Results: Allografts of saline or Ad-β-galactosidase controls were promptly rejected (mean survival time ± SE 7.6 ± 0.2 and 7.8 ± 0.3 days, respectively). AdvIL-10 significantly prolonged survival only in 2 out of 9 animals (23.2 ± 9.9 days), with vIL-10 expression detected on day 4. Survival was prolonged in 1 out of 5 animals by AdTGF-β3 (14.4 ± 5.3 days) despite the fact that the transgene was still observed after 14 days. While the combined injection of AdvIL-10 with AdCTLA4Ig did not protect the kidney from rejection (17.4 ± 4.6 days), AdTGF-β3 added to AdCTLA4Ig consistently prolonged the allograft lifespan in all animals (70.6 ± 39.6 days), inducing indefinite survival in 1 animal which showed long-term gene expression and T cells hyporesponsive to alloantigens. Conclusion: Overexpression of AdTGF-β3 concomitant with the blockade of the CD28/B7 pathway by AdCTLA4Ig induces strong immunosuppression that occasionally allows the acceptance of a fully major histocompatibility complex mismatched renal graft.
Neonatal Identification of Pituitary Aplasia: A Life-Saving Diagnosis
Authors: Scommegna Salvatore , Galeazzi Daniela , Picone Simonetta , Farinelli Edoardo , Agostino Rocco , Bozzao Alessandro , Boscherini Brunetto , Cianfarani Stefano
Published: April 2004

Background: Neonatal onset hypopituitarism is a life-threatening, potentially treatable endocrine disease. A possible cause is congenital absence of the anterior pituitary gland, a condition very rarely reported in the literature. Methods: A series of 5 cases of children with pituitary aplasia referred to the Centre of Paediatric Endocrinology ‘Rina Balducci’, Tor Vergata University, Rome, is presented. Results: Major clinical features in our patients were respiratory distress on the first day of life, in spite of uneventful pregnancy, labour and delivery, metabolic acidosis, non-cholestatic jaundice, hypotonia, severe hypoglycaemia, hypogenitalism, and midline defects. Diagnosis was established by endocrine tests during hypoglycaemia and hypothalamic-pituitary MRI scan. Symptoms disappeared soon after replacement therapy was started. Conclusion: We stress the importance of performing baseline endocrine tests as soon as possible during hypoglycaemia and MRI of the brain aimed at visualizing the hypothalamic-pituitary area in neonates with hypogenitalism and severe unexplained hypoglycaemia, so that the irreversible neurological and developmental consequences of panhypopituitarism can be prevented by adequate replacement therapy.
Dysphagia following Stroke
Authors: Paciaroni Maurizio , Mazzotta Giovanni , Corea Francesco , Caso Valeria , Venti Michele , Milia Paolo , Silvestrelli Giorgio , Palmerini Francesco , Parnetti Lucilla , Gallai Virgilio
Published: April 2004

Background: Dysphagia is common after stroke. We aimed to study the prognosis of dysphagia (assessed clinically) over the first 3 months after acute stroke and to determine whether specific neurovascular-anatomical sites were associated with swallowing dysfunction. Methods: We prospectively examined consecutive patients with acute first-ever stroke. The assessment of dysphagia was made using standardized clinical methods. The arterial territories involved were determined on CT/MRI. All patients were followed up for 3 months. Results: 34.7% of 406 patients had dysphagia. Dysphagia was more frequent in patients with hemorrhagic stroke (31/63 vs. 110/343; p = 0.01). In patients with ischemic stroke, the involvement of the arterial territory of the total middle cerebral artery was more frequently associated with dysphagia (28.2 vs. 2.2%; p < 0.0001). Multivariate analysis revealed that stroke mortality and disability were independently associated with dysphagia (p < 0.0001). Conclusions: The frequency of dysphagia was relatively high. Regarding anatomical-clinical correlation, the most important factor was the size rather than the location of the lesion. Dysphagia assessed clinically was a significant variable predicting death and disability at 90 days.
Brain White Matter Lesions in an Italian Family with Charcot-Marie-Tooth Disease
Authors: Sacco Simona , Totaro Rocco , Bastianello Stefano , Marini Carmine , Carolei Antonio
Published: April 2004

Type 1A, the most common form of Charcot-Marie-Tooth (CMT1A) disease, is characterized by demyelination of the peripheral nervous system. So far, only a few cases of the disease with concomitant brain white matter lesions have been described. We report an Italian family with CMT1A disease, consisting of the proband and 4 affected members, presenting with concomitant brain white matter lesions at magnetic resonance imaging. The association is particularly fascinating and might depend on an autoimmune mechanism, not yet clarified.
11- to 15-Year-Old Children of Women Who Danced during Their Pregnancy
Authors: Bellieni Carlo V. , Cordelli Duccio M. , Bagnoli Franco , Buonocore Giuseppe
Published: April 2004

Aim: To determine whether high levels of maternal physical activity (dancing during pregnancy), influenced the offspring. Materials and Methods: Sixty-four women (32 of whom had continued to dance for at least 2 months after the beginning of pregnancy) filled in a questionnaire to assess the health and behavior of their offspring, now 11–15 years of age. Results: More children born from women who had continued to dance during pregnancy needed to be rocked to sleep during their first year (p < 0.05). More children in the study group played musical instruments (p < 0.05). There were no significant differences between the groups regarding other parameters. Conclusions: The greater need to be rocked to fall asleep and the attitude to play musical instruments recorded in the children of dancers may be related to prenatal maternal movement. But they may also be due to other causes as discussed.
Literal and Extended use of Kinship Terms in Documentary Papyri
Authors: Dickey Eleanor
Published: March 2004

Kinship terms in papyrus letters do not always refer to actual relatives and so pose many problems for modern readers. But by examining all the kinship terms in six centuries of letters it is possible to discover some rules governing the use of kinship terms: in some situations they appear to be always literal, and in others they appear to be almost always extended, though a third group of contexts remains ambiguous. The rules are complex and depend on the particular kinship term involved, the date of writing, the use of names, the position of the kinship term in the letter, and the person to whom it connects the referent.
Egyptian Maat and Hesiodic Metis
Authors: Teeter Emily , Faraone Christopher
Published: March 2004

Metis appears twice in the Hesiodic corpus as an anthropomorphic goddess, who is courted and then ingested by Zeus. In the Theogony this narrative ends with the permanent stabilization of his monarchic rule over gods and men. We argue that the myth of Metis and Zeus most probably derives - directly or indirectly - from Egyptian royal ideology, as it is expressed most emphatically in a series of New Kingdom and later (i.e. 1500 BCE-200 CE) texts and relief sculptures that depict the offering to various monarchical male gods of the goddess Maat. Like Hesiodic Mêtis/mêtis, Maat appears in Egyptian texts both as an abstract idea (maat) and as an anthropomorphized goddess Maat and several odd details in the Hesiodic narratives can be explained by Egyptian influence, especially the idea that Zeus swallows Metis and that afterwards she gives him moral guidance. Metis and Egyptian Maat are both closely connected to the idea of legitimate monarchic rule, a relationship that is expressed by the insertion of Maat herself into the coronation names of Egyptian kings, much the same as Metis' name appears in two of the traditional epithets attached to Zeus.
1.5D inversion of lateral variation of Scholte‐wave dispersion
Authors: Bohlen Thomas , Kugler Simone , Klein Gerald , Theilen Friedrich
Published: April 2004

Reliable models of in‐situ shear‐wave velocities of shallow‐water marine sediments are important for geotechnical applications, lithological sediment characterization, and seismic exploration studies. We infer the 2D shear‐wave velocity structure of shallow‐water marine sediments from the lateral variation of Scholte‐wave dispersion. Scholte waves are recorded in a common receiver gather generated by an air gun towed behind a ship away from a single stationary ocean‐bottom seismometer. An offset window moves along the common receiver gather to pick up a local wavefield. A slant stack produces a slowness–frequency spectrum of the local wavefield, which contains all modes excited by the air gun. Amplitude maxima (dispersion curves) in the local spectrum are picked and inverted for the shear‐wave velocity depth profile located at the center of the window. As the window continuously moves along the common receiver gather, a 2D shear‐wave velocity section is generated. In a synthetic example the smooth lateral variation of surficial shear‐wave velocity is well reconstructed. The method is applied to two orthogonal common receiver gathers acquired in the Baltic Sea (northern Germany). The inverted 2D models show a strong vertical gradient of shear‐wave velocity at the sea floor. Along one profile significant lateral variation near the sea floor is observed.
Estimation of effective porosity using geostatistics and multiattribute transforms: A case study
Authors: Pramanik A. G. , Singh V. , Vig Rajiv , Srivastava A. K. , Tiwary D. N.
Published: April 2004

The middle Eocene Kalol Formation in the north Cambay Basin of India is producing hydrocarbons in commercial quantity from a series of thin clastic reservoirs. These reservoirs are sandwiched between coal and shale layers, and are discrete in nature. The Kalol Formation has been divided into eleven units (K‐I to K‐XI) from top to bottom. Multipay sands of the K‐IX unit 2–8 m thick are the main hydrocarbon producers in the study area. Apart from their discrete nature, these sands exhibit lithological variation, which affects the porosity distribution. Low‐porosity zones are found devoid of hydrocarbons. In the available 3D seismic data, these sands are not resolved and generate a composite detectable seismic response, making reservoir characterization through seismic attributes impossible. After proper well‐to‐seismic tie, the major stratigraphic markers were tracked in the 3D seismic data volume for structural mapping and carrying out attribute analysis. The 3D seismic volume was inverted to obtain an acoustic impedance volume using a model‐based inversion algorithm, improving the vertical resolution and resolving the K‐IX pay sands. For better reservoir characterization, effective porosity distribution was estimated through different available techniques taking the K‐IX upper sand as an example. Various sample‐based seismic attributes, the impedance volume, and effective porosity logs were used as inputs for this purpose. These techniques are map‐based geostatistical methods using the acoustic impedance volume, stepwise multilinear regression, probabilistic neural networks (PNN) using multiattribute transforms, and a new technique that incorporates both geostatistics and multiattribute transforms (either linear or nonlinear). This paper is an attempt to compare different available techniques for porosity estimation. On comparison, it is found that the PNN‐based approach using ten sample‐based attributes showed highest crosscorrelation (0.9508) between actual and predicted effective porosity logs at eight wells in the study area. After validation, the predicted effective porosity maps for the K‐IX upper sand are generated using different techniques, and a comparison among them is made. The predicted effective porosity map obtained from PNN‐based model provides more meaningful information about the K‐IX upper sand reservoir. In order to give priority to the actual effective porosity values at wells, the predicted effective porosity map obtained from PNN‐based model for the K‐IX upper sand was combined with actual effective porosity values using co‐kriging geostatistical technique. This final map provides geologically more realistic predicted effective porosity distribution and helps in understanding the subsurface image. The implication of this work in exploration and development of hydrocarbons in the study area is discussed.
VSP traveltime inversion for linear inhomogeneity and elliptical anisotropy
Authors: Slawinski Michael A. , Wheaton Chad J. , Powojowski Miro
Published: April 2004

To account for measured vertical seismic profiling (VSP) traveltimes, we study a velocity model described by three parameters. We assume that the velocity increases linearly with depth and is given in terms of parameters a and b, whereas the anisotropy is the result of elliptical velocity dependence and is given in terms of parameter χ. Using this model, we formulate an analytical expression for traveltime between a given source and a given receiver. This traveltime expression contains the three parameters that are present in the velocity model. To obtain the values of a, b, and χ, we use least‐squares fitting of this traveltime expression, with respect to measured traveltimes. This process of obtaining the parameters is exemplified by a study of traveltime data acquired with a two‐offset VSP in the Western Canada Basin. Having obtained a, b, and χ, we perform a statistical analysis, which shows good agreement between the field data and the modeled data. Furthermore, it shows that the elliptical velocity dependence, although small, is statistically significant.
Gassmann's equation and fluid‐saturation effects on seismic velocities
Authors: Han De‐hua , Batzle Michael L.
Published: April 2004

Gassmann's (1951) equations commonly are used to predict velocity changes resulting from different pore‐fluid saturations. However, the input parameters are often crudely estimated, and the resulting estimates of fluid effects can be unrealistic. In rocks, parameters such as porosity, density, and velocity are not independent, and values must be kept consistent and constrained. Otherwise, estimating fluid substitution can result in substantial errors. We recast the Gassmann's relations in terms of a porosity‐dependent normalized modulus Kn and the fluid sensitivity in terms of a simplified gain function G. General Voigt‐Reuss bounds and critical porosity limits constrain the equations and provide upper and lower bounds of the fluid‐saturation effect on bulk modulus. The “D” functions are simplified modulus‐porosity relations that are based on empirical porosity‐velocity trends. These functions are applicable to fluid‐substitution calculations and add important constraints on the results. More importantly, the simplified Gassmann's relations provide better physical insight into the significance of each parameter. The estimated moduli remain physical, the calculations are more stable, and the results are more realistic.
Nonlinear rock physics model for estimation of 3D subsurface stress in anisotropic formations: Theory and laboratory verification
Authors: Prioul Romain , Bakulin Andrey , Bakulin Victor
Published: April 2004

We develop a rock physics model based on nonlinear elasticity that describes the dependence of the effective stiffness tensor as a function of a 3D stress field in intrinsically anisotropic formations. This model predicts the seismic velocity of both P‐ and S‐waves in any direction for an arbitrary 3D stress state. Therefore, the model overcomes the limitations of existing empirical velocity‐stress models that link P‐wave velocity in isotropic rocks to uniaxial or hydrostatic stress. To validate this model, we analyze ultrasonic velocity measurements on stressed anisotropic samples of shale and sandstone. With only three nonlinear constants, we are able to predict the stress dependence of all five elastic medium parameters comprising the transversely isotropic stiffness tensor. We also show that the horizontal stress affects vertical S‐wave velocity with the same order of magnitude as vertical stress does. We develop a weak‐anisotropy approximation that directly links commonly measured anisotropic Thomsen parameters to the principal stresses. Each Thomsen parameter is simply a sum of corresponding background intrinsic anisotropy and stress‐induced contribution. The stress‐induced part is controlled by the difference between horizontal and vertical stresses and coefficients depending on nonlinear constants. Thus, isotropic rock stays isotropic under varying but hydrostatic load, whereas transversely isotropic rock retains the same values of dimensionless Thomsen parameters. Only unequal horizontal and vertical stresses alter anisotropy. Since Thomsen parameters conveniently describe seismic signatures, such as normal‐moveout velocities and amplitude‐variation‐with‐offset gradients, this approximation is suitable for designing new methods for the estimation of 3D subsurface stress from multicomponent seismic data.
Measurement of acoustic properties of near‐surface soils using an ultrasonic waveguide
Authors: Long Rob , Vogt Thomas , Lowe Mike , Cawley Peter
Published: April 2004

A technique is presented that uses a circular ultrasonic waveguide to measure the bulk shear (S‐wave) and longitudinal (P‐wave) velocities of unconsolidated media, with particular application to near‐surface soils. The technique requires measuring the attenuation characteristics of the fundamental longitudinal mode that propagates along an embedded bar, from which the acoustic properties of the surrounding medium are inferred. The principles behind the technique are discussed, and the results of an experimental laboratory validation are presented, followed by details of in‐situ soil property measurements obtained at various sites in urban areas of the United Kingdom.
Fast monostatic GPR modeling
Authors: Baradello Luca , Carcione José M. , Gei Davide
Published: April 2004

We propose the exploding‐reflector method to simulate a monostatic survey with a single simulation. The exploding reflector, used in seismic modeling, is adapted for ground‐penetrating radar (GPR) modeling by using the analogy between acoustic and electromagnetic waves. The method can be used with ray tracing to obtain the location of the interfaces and estimate the properties of the medium on the basis of the traveltimes and reflection amplitudes. In particular, these can provide a better estimation of the conductivity and geometrical details. The modeling methodology is complemented with the use of the plane‐wave method. The technique is illustrated with GPR data from an excavated tomb of the nineteenth century.
A classification for the pressure‐sensitivity properties of a sandstone rock frame
Authors: MacBeth Colin
Published: April 2004

A three‐parameter formula is proposed to describe the sensitivity of the bulk modulus (κ) or shear rigidity (μ) for a sandstone rock frame under applied isotropic loading. The theoretical basis for this relation is the use of excess compliance as a pseudo function to describe all internal weaknesses in the rock, regardless of their origin. The law is fitted to 179 sets of laboratory measurements on unsaturated reservoir core and outcrop sandstones that have low to moderate porosity and a range of clay fractions and cementation. A stress index, defined to quantitatively rank the reservoir sands, indicates that laboratory‐derived pressure sensitivity is highest (10% per MPa maximum) for the clean, moderate‐porosity Paleocene sands from the Forties Formation and West of Shetlands, whereas the lower‐porosity, cemented, and more‐consolidated Permian sands rank as least pressure sensitive (1% per MPa maximum). Higher‐porosity sands are stress sensitive because of the overall rock‐frame compressibility. All of the sands appear to contain microcracks induced by core unloading, with some harder rocks being more susceptible to this damage. Theory predicts, and laboratory data confirm, that VP/VS generally increases with pressure, although a small proportion of the samples do show the opposite trend. The sign and magnitude of the pressure sensitivity for η [(VS/VP)2] may relate to the intensity of the microcracking in the samples.
Seismic imaging of reservoir flow properties: Time‐lapse pressure changes
Authors: Vasco Don W.
Published: April 2004

Time‐lapse fluid pressure and saturation estimates are sensitive to reservoir flow properties such as permeability. In fact, given time‐lapse estimates of pressure and saturation changes, one may define a linear partial differential equation for permeability variations within the reservoir. The resulting linear inverse problem can be solved quite efficiently using sparse matrix techniques. An application to a set of crosswell saturation and pressure estimates from a CO2 flood at the Lost Hills field in California demonstrates the utility of this approach. The pressure and saturation estimates are mapped into reservoir permeability variations between the boreholes. The resulting permeability estimates agree with a permeability log in an adjacent well and are in accordance with water and CO2 saturation changes imaged in the interwell region.
Shear waves in acoustic anisotropic media
Authors: Grechka Vladimir , Zhang Linbin , Rector James W.
Published: April 2004

Acoustic transversely isotropic (TI) media are defined by artificially setting the shear‐wave velocity in the direction of symmetry axis, VS0, to zero. Contrary to conventional wisdom that equating VS0= 0 eliminates shear waves, we demonstrate their presence and examine their properties. Specifically, we show that SV‐waves generally have finite nonzero phase and group velocities in acoustic TI media. In fact, these waves have been observed in full waveform modeling, but apparently they were not understood and labeled as numerical artifacts.

Acoustic TI media are characterized by extreme, in some sense infinite strength of anisotropy. It makes the following unusual wave phenomena possible: (1) there are propagation directions, where the SV‐ray is orthogonal to the corresponding wavefront normal, (2) the SV‐wave whose ray propagates along the symmetry axis is polarized parallel to the P‐wave propagating in the same direction, (3) P‐wave singularities, that is, directions where P‐ and SV‐wave phase velocities coincide might exist in acoustic TI media.

We also briefly discuss some aspects of wave propagation in low‐symmetry acoustic anisotropic models. Extreme anisotropy in those media creates bizarre phase‐ and group‐velocity surfaces that might bring intellectual delight to an anisotropic guru.
Finite‐difference modeling of viscoelastic and anisotropic wave propagation using the rotated staggered grid
Authors: Saenger Erik H. , Bohlen Thomas
Published: April 2004

We describe the application of the rotated staggered‐grid (RSG) finite‐difference technique to the wave equations for anisotropic and viscoelastic media. The RSG uses rotated finite‐difference operators, leading to a distribution of modeling parameters in an elementary cell where all components of one physical property are located only at one single position. This can be advantageous for modeling wave propagation in anisotropic media or complex media, including high‐contrast discontinuities, because no averaging of elastic moduli is needed. The RSG can be applied both to displacement‐stress and to velocity‐stress finite‐difference (FD) schemes, whereby the latter are commonly used to model viscoelastic wave propagation. With a von Neumann‐style anlysis, we estimate the dispersion error of the RSG scheme in general anisotropic media. In three different simulation examples, all based on previously published problems, we demonstrate the application and the accuracy of the proposed numerical approach.
Nonstretch NMO
Authors: Perroud Hervé , Tygel Martin
Published: April 2004

We describe a new implementation of the normal‐moveout (NMO) correction that is routinely applied to common‐midpoint (CMP) reflections prior to stacking. The procedure, called nonstretch NMO, automatically avoids the undesirable stretch effects that are present in conventional NMO. Under nonstretch NMO, a significant range of large offsets that normally would be muted in the case of conventional NMO can be kept and used, thereby leading to better stack and velocity determinations. We illustrate the use of nonstretch NMO by applying it to synthetic and real data sets obtained from high‐resolution (HR) seismic and ground‐penetrating radar (GPR) measurements.
Bispectral Electroencephalographic Analysis of head‐injured Patients in the Emergency Department
Authors: Haug Eric , Miner James , Dannehy Mark , Seigel Todd , Biros Michelle
Published: April 2004

Objectives: Bispectral analysis of single‐lead electroencephalographs (BIS) has proven valuable in assessing the level of awareness in sedated patients. In this study, the authors sought to determine if BIS values had a predictive value in patients with traumatic brain injuries (TBIs). Therefore, the objective was to determine in emergency department (ED) patients presenting with head trauma whether BIS and Glasgow Coma Scale score (GCS) prior to sedation would be sensitive and specific in predicting TBI. Methods: A convenience sample of patients with known or suspected head trauma presenting between June and August of both 2001 and 2002 were entered into the study by having a BIS monitor placed immediately on presentation to the ED. BIS and GCS scores were collected every 2 minutes. Head computed tomography (CT) results and discharge dictations were then evaluated to determine the presence of TBI. RESULTS: Fifty‐two patients were entered into the study; 13 were excluded due to receiving sedatives prior to enrollment. Of the remaining 39 patients, 14 had intracranial hemorrhage on initial head CT. Of these 14, two had BIS scores over 95. Both of these were neurologically intact at discharge. Eleven of the 12 remaining patients died or left the hospital neurologically impaired. Of the patients with no abnormalities on initial head CT, 19 of 25 had initial BIS scores >95 and all left the hospital neurologically intact. Of the patients with normal initial head CT and initial BIS scores < 95, four of six died or were neurologically impaired at discharge. Twenty of 39 patients presented with an initial GCS of 15; four of 20 had an initial BIS score < 95, three of whom were neurologically impaired at discharge. The 16 of 20 with BIS >95 left the hospital neurologically intact. All patients with a GCS of 14 had BIS scores >95 and left the hospital neurologically intact. All patients with a GCS of 13 had initial BIS scores < 95 and were neurologically impaired at discharge. One patient with a GCS of 11 and a BIS score of 67 left the hospital neurologically intact; all other patients with a GCS < 12 had a BIS < 95 and left the hospital with a neurologic deficit. Conclusions: BIS scores obtained prior to sedative medicines in the face of trauma are predictive of TBI and neurologic outcome at discharge.
Development of Polyethylene Copolymers Manufacturing Technologies and Synthesis of New Functionalized Polyolefins with Designed Catalysts
Authors: Imuta Jun-ichi , Todo Akira , Tsutsui Toshiyuki , Hachimori Toshimi , Kashiwa Norio
Published: April 2004

Advanced supported metallocene catalysts for commercialization were developed in the consequence of improving catalyst performances and accomplishing industrial tasks. The relationship between molecular structures and physical properties of ethylene and α-olefin copolymers produced with metallocene catalysts was also investigated. Metallocene catalyzed ethylene/α-olefin copolymers have excellent physical properties (high strength, high clarity, good heat sealability) owing to a homogeneous molecular structure that had never been achieved by conventional Ziegler–Natta catalysts. We have also succeeded in producing long chain branched ethylene copolymers with narrow molecular weight distributions but excellent melt properties by the use of the catalyst technologies to control of the branches in a polymer chain. Moreover, we have found the first example of metallocene-catalyzed allyl alcohol or allylamine incorporation having only one CH2 chain spacer into the nonpolar polymer backbone, using new metallocene and methylaluminoxane with high activity at high temperature. This is the first example of predominant chain end and/or site-selective introduction of polar groups into the polyolefins.
Aggregation of Octahedral Thiolato Complexes by Forming Sulfur-Bridged Structures with Transition Metal Ions
Authors: Konno Takumi
Published: April 2004

The main developments in rational construction of chiral metallo-aggregates based on octahedral metal complexes with 2-aminoethanethiolate (aet) or l-cysteinate (l-cys), as well as their functionality as an S-donating chiral metalloligand, are reviewed in this paper. The reactions of the tris(thiolato)-type fac(S)-[M(aet or l-cys-N,S)3]0 or 3− (M = CoIII, RhIII, IrIII) with transition metal ions gave a variety of S-bridged metallo-aggregates, the structures and chiral properties of which are highly dependent on the nature of the reacting metal ions. The aggregation of the bis(thiolato)-type cis(S)-[Co(aet)2(en)]2+ was also performed through the replacement of a NiII ion in [Ni{Co(aet)2(en)}2]4+ by other transition metal ions. While aggregation of these tris(thiolato)- and bis(thiolato)-types of octahedral units commonly produced discrete S-bridged polynuclear structures, one-dimensional and two-dimensional extended polymeric structures, besides a discrete trinuclear structure, were constructed by the reactions of the mono(thiolato)-type [Co(aet or l-cys-N,S)(en)2]2+ or + with silver(I) ion, because of the adoption of μ3-thiolato bridging mode and/or the coordination ability of the free carboxylate group.
Magnetic Resonance Energy and Aromaticity of Polycyclic Aromatic Hydrocarbon Dianions/Dications
Authors: Aihara Jun-ichi
Published: April 2004

Molecular dianions/dications of many polycyclic aromatic hydrocarbons (PAHs) have long been regarded as antiaromatics because of their global paratropic π-electron current. However, many of them are supposed to be aromatic due to their positive topological resonance energies (TREs). In order to reconcile such energetic and magnetic criteria of aromaticity, we derived a new TRE-like energetic quantity from the magnetic response of the π-system and called it a magnetic resonance energy (MRE). MRE was found to be highly correlative with TRE for a variety of PAHs and their molecular dianions/dications. We can now discuss energetic and magnetic criteria of aromaticity unambiguously on this theoretical basis. Many PAH dianions/dications indeed turned out to be aromatic with positive MREs even if they exhibit paratropic currents along the periphery of the π-system.
Comparative Studies on the Stability of a Chelate-Ring Unit in Dynamic Aspects. Chelate-Rings of the Cu(II) Complexes Composed of [N-(Glycyl)], [N-(β-Alanyl)], and [N-(2-Aminoethyl)] Moieties
Authors: Hanaki Akira , Ozawa Toshihiko , Funahashi Yasuhiro , Odani Akira
Published: April 2004

The kinetic stability of a chelate-ring unit in Cu(H−1GlyGly), Cu(H−1β-AlaGly), and Cu(EDMA) complexes has been inspected by stopped-flow spectroscopy. Those three Cu(II) complexes reacted with cysteine (CysH) or penicillamine (PesH) to form primarily ternary complexes, formulated as Cu(H−1L)(Rs−); L = GlyGly and β-AlaGly, and Cu(EDMA)(Rs−); where Rs− represents the aminothiolates. The chelate-ring units composed of [N-(Gly)]-, [N-(β-Ala)]-, and [N-(2-aminoethyl)]-moieties in Cu(H−1GlyGly), Cu(H−1β-AlaGly), and Cu(EDMA) were conserved, respectively, in the corresponding ternary complexes. The rate of the ternary complex formation was very rapid, so much so that the rate constants, k1+, could not be determined by the conventional stopped-flow techniques. The ternary complexes upon forming reacted with the RsH to produce the binary Cu(Rs−)2 species. Thus, the observables were limited to the rate constants, k2+, for the transformation from Cu(H−1L)(Rs−) to Cu(Rs−)2. The kinetic stabilities of those chelate-ring units were compared based on the rate constant, k2+, and equilibrium constant, K2. The stability was arranged as follows: [N-(Gly)]- > [N-(2-aminoethyl)]- > [N-(β-Ala)]-unit. Though Cu(EDMA) was kinetically stable, the Cu(II) in Cu(EDMA)(Rs−) was rapidly delivered by a nucleophilic attack of RsH to form Cu(Rs−)2. On the contrary, Cu(H−1GlyGly) was kinetically less stable than Cu(EDMA), but delivery of the Cu(II) from Cu(H−1L)(Rs−), by the proton-assisted mechanism, was comparatively slow.
Tetranuclear NiII and Dinuclear MnIII Complexes Derived from a New Macrocyclic Ligand with Four Endogenous Phenolic Groups
Authors: Ikeda Kazuhide , Matsufuji Kanako , Ohba Masaaki , Kodera Masahito , Okawa Hisashi
Published: April 2004

A tetranucleating macrocyclic ligand with four endogenous phenolic groups is obtained by the condensation of 3-aminomethyl-5-methylsalicylaldehyde in the presence of metal ion as two tetranuclear NiII complexes, [Ni4(L)(OH)(H2O)4](ClO4)3 (1) and [Ni4(L)(O)(dmf)4](ClO4)2 (2), and a dinuclear MnIII complex, [Mn2(H2L)(OH)(AcO)2(H2O)]Br (3). X-ray crystallographic studies for [Ni4(L)(OH)(H2O)8](ClO4)3·7H2O (1′) indicate that the macrocyclic ligand accommodates four NiII ions, producing a square Ni4 core with μ4-hydroxo group at the center of the core. Water molecules occupy the axial sites of each Ni affording a nearly octahedral geometry about the metal. Complex 2 has a similar tetranuclear Ni4-core possessing a μ4-oxo group at the center of the core. In complex 3, the di-protonated ligand (H2L)2− accommodates two MnIII ions, affording a (μ-hydroxo)(μ-acetato)dimanganese(III) core. Magnetic studies for 1 and 2 indicate a ferromagnetic interaction between the adjacent NiII centers and an antiferromagnetic interaction between the diagonal NiII centers. Complex 3 shows a weak antiferromagnetic interaction between the two MnIII ions.
Pyrolysis of High-Molecular-Weight Complex Organics Synthesized from a Simulated Interstellar Gas Mixture Irradiated with 3 MeV Proton Beam
Authors: Takano Yoshinori , Tsuboi Taiki , Kaneko Takeo , Kobayashi Kensei , Marumo Katsumi
Published: April 2004

High-molecular-weight organic matter synthesized from mixtures of carbon monoxide, ammonia, and water gases similar to those found in the interstellar medium were irradiated with a 3 MeV proton beam and analyzed by Curie-point pyrolysis with detection by a gas chromatograph and a mass spectrometer (Pyr–GC–MS). A wide variety of organic compounds, not only a number of amide compounds, but also heterocyclic and polycyclic aromatic hydrocarbons (PAHs), were detected among the products of the pyrolysis. Detection of biologically interesting compounds, such as glycolamide (HOCH2CONH2), is also cosmochemically interesting. The present data show that primary and primitive organic matter serving as “precursors” to bioorganic compounds, such as amino acids, nucleic acid bases, and sugar, might have been formed in a gaseous mixture of similar composition to that of the interstellar dust environment. Consequently, the matrix of extraterrestrial organic compounds delivered by comets and meteorites may have played an important role in the early stages of chemical evolution on the primitive Earth.
Self-Assembly of Synthetic Bacteriochlorophyll-f Analogues Having C8-Formyl Group
Authors: Sasaki Shin-ichi , Tamiaki Hitoshi
Published: April 2004

31-Epimerically pure C8-formyl analogues Zn–3R/S of zinc methyl bacteriopheophorbide-f (Zn–MBPhe-f) were synthesized. Their spectroscopic and self-aggregation properties were compared to those of Zn–MBPhe-f possessing the C7-formyl group (Zn–2R/S) as a model compound of bacteriochlorophyll-f. Movement of a formyl group from the 7- to 8-position as in Zn–2 → Zn–3 caused large spectral changes in both monomeric and oligomeric forms. Monomeric Zn–3R/S in THF showed a more red-shifted Qy peak (650 nm) than Zn–2R/S (628 nm), but both afforded the same Soret maximum at 448 nm. Self-aggregates of Zn–3R/S in 6% (v/v) THF–H2O gave a more red-shifted Qy peak accompanied by a large diastereomeric control in the oligomeric Qy peaks.
Control Crystallization of Calcium Carbonate in Aqueous Solution with In-Situ Radical Polymerization of Sodium Acrylate as a Latent Inductor for Crystal Nucleation and Growth
Authors: Naka Kensuke , Keum Dong-Ki , Tanaka Yasuyuki , Chujo Yoshiki
Published: April 2004

Crystallization of CaCO3 with in-situ radical polymerization of sodium acrylate in aqueous solution was carried out by a double jet method to prevent heterogeneous nucleation at glass walls. The concentration of sodium acrylate was 1.71 mM and the feed ratio of sodium acrylate to calcium ions was 0.62. After addition of the calcium reactants into the aqueous solution of sodium acrylate was completed, an aqueous solution of potassium peroxodisulfate as a water-soluble radical initiator was added to the reaction mixture after incubation at 30 °C for several minutes (1, 3, or 20 min). Three different crystal polymorphs of CaCO3 (aragonite, vaterite, and calcite) were selectively induced by changing the time for adding the radical initiator to a calcium carbonate solution with sodium acrylate. Formation of crystalline CaCO3 in the presence of sodium acrylate with the radical initiator at different feed ratio of sodium acrylate to calcium ions was also studied. The higher concentration of sodium acrylate increased sizes of vaterite spherical particles. The present results indicate that the final crystalline phases are highly sensitive to the presence of the active additives at the very initial nucleation stage (within several minutes).