bluuebunny/crossref_metadata_2025 huggingface dataset:
Karakoram fault zone rocks cool in two phases
Authors: DUNLAP W. JAMES , WEINBERG ROBERTO F. , SEARLE MIKE P.
Published: December 2007

The Karakoram fault zone of Ladakh, India, is a major strike-slip boundary along which the tectonic evolution of Tibet has been accommodated. In this paper
40
Ar/
39
Ar isotopic age data are integrated with structural and metamorphic data to infer an exhumation history for granites and low- to intermediate-grade metamorphic rocks exposed adjacent to two strands of the fault zone. Near Tangtse, leucogranites which crystallized
c
. 17 Ma ago are cut by the Karakoram fault zone, indicating that fault movement was initiated subsequent to 17 Ma. The
40
Ar/
39
Ar data give temperature-time histories which indicate that the <17 Ma metamorphic rocks within the fault zone were exhumed differentially relative to the adjacent (and already cooled to <150°C) Ladakh Batholith, while cooling progressively through amphibolite to below greenschist facies temperatures.

Two phases of rapid cooling of Karakoram fault zone rocks are evident, one at
c
. 17 Ma to
c
. 13 Ma, and another, following an intervening period of relatively slow cooling, starting at
c
. 8 Ma and continuing until at least 7 Ma. Uplift since
c
. 17 Ma via dextral oblique thrusting has resulted in exhumation from amphibolite facies metamorphic conditions, possibly with a larger thrust component from 17 to 13 Ma, followed by a change to dominant strike-slip motion at about 13 Ma. Rapid cooling starting at
c
. 8 Ma at greenschist facies temperatures is probably the result of renewed oblique thrusting. It is notable that the two episodes of rapid cooling recorded in Karakoram fault zone rocks coincide with episodes of exhumation in the Pakistani Karakoram and also in southern Tibet.
Integrated chronostratigraphy of the Vendian System of Siberia: implications for a global stratigraphy
Authors: PELECHATY SHANE M.
Published: December 2007

Integrated δ
13
C chemostratigraphy and sequence stratigraphy are developed for a succession of Vendian strata (Nokhtuisk section) on the southern margin of the Siberian platform. The carbonates exhibit secular variations in δ
13
C and at least three major depositional sequences that encompass the last
c.
20 million years –(<565–545 Ma) of Vendian time. Correlation of these events with key sections in eastern Siberia reveals the development of three cratonic sequences that partition the Vendian System of Siberia into high-resolution time slices (third-order sequences). The third-order events form a larger depositional sequence, which is correlated with greater confidence on a global-scale. With the aid of global chemostratigraphic constraints, the second-order sequence in Siberia is interpreted to represent the youngest of at least two sequences of eustatic origin that span the latest 60 million years of terminal Neoproterozoic time. Evidence for repeated glaciations in many basins at this time provides a plausible mechanism for the third-order cratonic sequences in Siberia. However, effects due to sea-floor spreading related to the break-up of the supercontinent Rodinia are invoked as the primary mechanism for the longer-term, second-order sea-level fluctuations.
Lithostratigraphy of the Cretaceous (Barremian–Santonian) Hold with Hope Group, NE Greenland
Authors: KELLY SIMON R. A. , WHITHAM ANDREW G. , KORAINI A. MUNIF , PRICE SIMON P.
Published: December 2007

The finest exposures of Barremian to Santonian sedimentary rocks in the northern North Atlantic region are exposed in Hold with Hope, NE Greenland. These rocks comprise the Hold with Hope Group which, together with its constituent formations and members are defined here as new lithostratigraphic units. The strata are dated as Cretaceous by use of molluscan macrofaunas and dinoflagellate cysts. The marine mudstone-dominated Hold with Hope Group is over 1300 m thick and is divided into the Steensby Bjerg and Home Forland formations. The sandstone-dominated Steensby Bjerg Formation (Barremian–Albian) is 300 m thick. It rests with angular unconformity on sandstones attributed to the Vardekløft Formation (Middle Jurassic) and is subdivided into the Diener Bjerg, Gulelv, Stribedal, Blåelv, Stensiö Plateau and Rødelv members. The mudstone-dominated Home Forland Formation (Albian–Santonian) is over 1000 m thick. It rests unconformably on the Steensby Bjerg, Vardekløft and Wordie Creek (Triassic) formations. It is subdivided into the Fosdalen, Nanok, Østersletten, and Knudshoved members. The Hold with Hope Group is overlain unconformably by Tertiary basalts and sedimentary rocks. The original proximity of Hold with Hope to the Vøring Basin is significant for possible Cretaceous hydrocarbon plays on the formerly adjacent NW European margin.
U–Pb dating of stockwork zircons from the eastern Iberian Pyrite Belt
Authors: NESBITT R. W. , PASCUAL E. , FANNING C. M. , TOSCANO M. , SÁEZ R. , ALMODÓVAR G. R.
Published: December 2007

Zircons found in the stockwork zones of the massive sulphide Los Frailes deposit, Iberian Pyrite Belt, are interpreted to have grown during the hydro-thermal alteration of host felsic volcanic rocks. Ion microprobe (SHRIMP) dating gives a
206
Pb/
238
U age of 345.7 ± 4.6 Ma (2σ) and together with published spore data from the deposit suggest an age of uppermost Devonian to lowermost Carboniferous. Stockwork zircons offer the possibility of precisely defining the emplacement ages of these giant sulphide accumulations over the whole Pyrite Belt and from this will emerge estimates of the thermal budget necessary to generate the deposits.
Ice-flow stages and glacial bedforms in north central Ireland: a record of rapid environmental change during the last glacial termination
Authors: McCABE A. MARSHALL , KNIGHT JASPER , McCARRON STEPHEN G.
Published: December 2007

Satellite imagery is a useful tool to assess large-scale (>10
3
km
2
) geological patterns. Satellite imagery of north central Ireland shows cross-cut and overprinted subglacial bedform patterns. Bedform lineations, supported by sedimentary evidence, are used to reconstruct four ice-flow stages (named A-D) during the termination of the last (Devensian) glaciation (22 000–13 000 radiocarbon (
14
C) years
BP
).

Flow stage A relates to southwesterly flow of Scottish ice across eastern Ireland. Flow stage B, during the last glacial maximum
(c.
25 000–22 000
14
C years BP), records southeasterly ice-flow from dispersal centres in northern parts of Ireland. Transverse subglacial ridges (Rogen moraines) formed during stage B are the largest area of this ridge type in western Europe. Flow stage C records erosional headcutting in the Rogen moraine field and sediment streamlining (drumlinization) by ice streams drawn into the Irish Sea Basin. This flow stage is constrained by AMS radiocarbon dates from marine microfaunas to around 14 500
14
C years BP. Flow stage D records drumlinization from an inland centre in the Lough Neagh Basin.

Overall bedform patterns can be used to reconstruct ice mass history and evaluate controls on ice activity, including millennial-scale changes in amphi-North Atlantic climate. Field evidence of bedform relationships also casts doubt on current concepts of drumlinization and the role of pervasive sediment deformation in glacial systems.
Actively growing siliceous oncoids in the Waiotapu geothermal area, North Island, New Zealand
Authors: JONES BRIAN , RENAUT ROBIN W. , ROSEN MICHAEL R.
Published: December 2007

Oncoids that are actively growing in some of the shallow-water pools around Champagne Pool, Waiotapu, New Zealand, are formed of amorphous silica (opal-A) with minor amounts of native sulphur. The growth of these oncoids is being mediated by a high-diversity microbial biota that achieves optimal growth in waters that have a temperature of 35–42°C and pH of 6.6–6.9. Although this biota is dominated by coccoid, bacilliform, and filamentous cyanobacteria, sulphur-oxidizing bacteria are common in the cortical laminae of some oncoids. In addition, diatoms and silicified pollen grains are present in some cortical laminae. The silicified microbes are superbly preserved with their three-dimensional form and some of their internal structures being apparent, including the sites of sulphur globules in the sulphur-oxidizing bacteria. The microbes probably acted as templates for silica precipitation and thereby mediated the growth of the oncoids.

Some cortical laminae are formed entirely of silicified pollen grains that came from the
Pinus radiata
that grow in the exotic pine plantations around Champagne Pool. By using these laminae as a record of the annual pollination event (typically in September–November), it can be shown that many of the oncoids are <15 years old and that the cortical laminae grew at 0.2–1.0 mm (average 0.35 mm) per year. The average daily rate of silica precipitation (0.5–2.75 μm, average 1 μm) is high compared to the average size of the microbes (commonly < 1 μm in length and diameter). This rapid rate of silica precipitation accounts for the superb preservation of the microbes and is consistent with silicification of the microbes within days of their demise.
Palaeokarst systems in the Neoproterozoic of eastern North Greenland in relation to extensional tectonics on the Laurentian margin
Authors: SMITH M. P. , SOPER N. J. , HIGGINS A. K. , RASMUSSEN J. A. , CRAIG L. E.
Published: December 2007

Palaeokarst, in the form of large, uncollapsed cave systems, is described from the Proterozoic of Kronprins Christian Land, eastern North Greenland. The endokarst, of entirely meteoric origin, is developed in dolostones of the Fyns Sø Formation (Hagen Fjord Group, Riphean). At one locality, Hjørnegletscher, shallow, sub-horizontal phreatic conduits are present below an unconformity surface and are infilled by the overlying Ediacaran Kap Holbæk Formation. In Sæfaxi Elv, the unconformity is overlain by the Wandel Valley Formation, an Early Ordovician carbonate sequence that is widely transgressive over northeastern Greenland. Vertical vadose fissures extend down towards the phreas, but the cave systems are again filled by Kap Holbæk Formation sediments. At Hjørnegletscher, channels up to 40 m wide incise the phreatic system, pointing to relative base-level lowering before, or during, deposition of the Kap Holbaek Formation.

Recognition of a depositional hiatus between the Fyns S0 and Kap Holbaek formations, in what was previously thought to be a continuous Vendian Hagen Fjord sequence, has implications for regional correlation and tectonics. The unconformity could represent most of Vendian time, accounting for the absence, in this area, of glaciogenic sedimentary rocks in the Hagen Fjord Group. This permits correlation of the Fyns SøFormation with other end-Riphean transgressive carbonate sequences developed in East Greenland, Svalbard and perhaps Scotland, that represent the culmination of a major pre-Iapetan rift-sag cycle.

Secondly, recognition of the scale of the sub-Wandel Valley unconformity points to regional uplift and tilting of northeastern Greenland in mid-Cambrian to earliest Ordovician time. This must represent a phase of renewed extension of the Iapetus passive margin that is unique to this corner of Laurentia, not terrane collision as previously suggested.
Testing the predictive capability of curvature analyses
Authors: Bergbauer S.
Published: December 2007

The curvature of geological surfaces has been used to predict areas of elevated strain, deformation and fracture density. The research presented here tests if and to what extent a geometric measure such as normal surface curvature can be used as a proxy for deformation by comparing field observations with geometric modelling results. This is achieved by first quantifying fracturing in outcrop and then by performing a curvature analysis of the deformed bedding surface. This research suggests that curvature analysis by itself does not allow for the prediction of deformation: fracture density in the Emigrant Gap anticline is unrelated to horizon curvature, and synfolding fractures are aligned with prefolding fractures instead of the directions of principal curvature.

Normal surface curvature by itself has only limited value in predicting strain or fracture density; however, surface curvature is a unique descriptor of shape. Describing the geometry of a horizon quantitatively is an essential first step when attempting to compare physical and numerical models with natural surfaces. The tools presented here allow for unique descriptions of three dimensional folded surfaces that are based on the normal surface curvature, and they provide the necessary mathematical rigour and flexibility to allow for descriptions of non-cylindrical folded surfaces.
Testing fault transmissibility predictions in a structurally dominated reservoir: Ringhorne field, Norway
Authors: Myers R. D. , Allgood A. , Hjellbakk A. , Vrolijk P. , Briedis N.
Published: December 2007

At Ringhorne field, in the North Sea, judicious well placement and high quality 3D seismic data allow good control over stratigraphic and structural frameworks. In particular, two near-horizontal producing wells about 150 m apart on both sides of a critical normal fault are key for deciphering the fault effects on flow. These elements make this field ideal for using production data to constrain a range of process-based fault permeability predictions in a siliciclastic reservoir. A high resolution (50 m×50 m×1.8 m) faulted geological model, constructed in Petrel™, was used as input to process-based fault permeability predictions. Subsequent multiphase simulation and testing identified critical stratigraphic connections across shale layers and structural connections along a faulted relay around an isolated fault block. The simulations were used systematically as a probe to investigate both these and other controls on production and determine the likely range for permeability of fault zone materials, which are inferred to include deformed shales, sands, and minor cements. This study leverages the most pertinent observations and best constrained interpretations in the field to attempt to extract accurate, quantitative information on fault properties. A range of predicted fault permeability cases, linked to particular fault movement timing scenarios, were tested. The middle case, from a fault timing perspective, was determined to provide the best overall flow simulation match to all actual production information, providing valuable feedback for our process-based fault property prediction approach. Establishing the link between predicted and actual flow, and pressure history in response to critical reservoir plumbing elements, is paramount for evaluating and improving fault permeability predictions.
Structural evolution of the Penguins Cluster, UK northern North Sea
Authors: Domínguez R.
Published: December 2007

The Penguins Cluster is a group of four oil and gas fields in the northern end of the East Shetland Basin. Its structural complexity is caused by the interaction between two or more fault trend populations, fault reactivation and the impact of faulting on the Brent reservoir architecture. This structural picture is further complicated by a NW–SE trending basement lineament interpreted as a Caledonian shear zone. The present day structural configuration is the result of two Mesozoic rifting episodes and their associated thermal subsidence phases. The Permo-Triassic rifting created a number of north–south-trending tilted fault blocks, and was followed by a period of tectonic quiescence until the Middle Jurassic, when a faulting episode coeval with the Brent Group deposition caused footwall rotation, uplift and erosion of the upper Rannoch Formation prior to the deposition of the Etive Formation across the area. The rifting climaxed in the late Jurassic, when the reactivation of pre-existing faults under oblique-slip conditions in the Penguin C Field created small-scale lozenge-shaped transpressional and transtensional fault blocks. The presence of reverse faults in the area is explained with a continuous kinematic model of structural evolution and oblique-slip fault reactivation rather than positive basin inversion.
Coupled geomechanics–flow modelling at and below a critical stress state used to investigate common statistical properties of field production data
Authors: Zhang X. , Koutsabeloulis N. C. , Heffer K. J. , Main I. G. , Li L.
Published: December 2007

An areal model of a fractured/faulted reservoir with 49 wells is developed that incorporates fully-coupled geo-mechanics and fluid flow. It is a generic example of a pattern waterflood although it is inspired by a parallel study of the Gullfaks reservoir in the North Sea, in which stress-related, fault-related and long-range correlations in rate fluctuations are observed. Based on this model, three scenarios are examined in terms of different initial stress states prior to production, each of which involves 36 months of production and injection in the presence of fracture sets and faults. The results support the concept that the long-range, stress-related and fault-related characteristics of correlations in rate fluctuations, observed not only in the Gullfaks data, but also in several other fields worldwide, are symptomatic of a system near a geomechanical critical point. These characteristics are not observed in models that are sub-critical. Short-range rate correlations are likely to exist where there are highly permeable zones between producers and injectors. Long-range rate correlations occur only within critically-stressed regions where there is active shearing or fault reactivation. The modelling results are consistent with field evidence suggesting that incipient shearing is an important mechanism coupled with reservoir flow behaviour.
Seismic anisotropy as an indicator of reservoir quality in siliciclastic rocks
Authors: Kendall J.-M. , Fisher Q. J. , Crump S. Covey , Maddock J. , Carter A. , Hall S. A. , Wookey J. , Valcke S. L. A. , Casey M. , Lloyd G. , Ismail W. Ben
Published: December 2007

Improving the accuracy of subsurface imaging is commonly the main incentive for including the effects of anisotropy in seismic processing. However, the anisotropy itself holds valuable information about rock properties and, as such, can be viewed as a seismic attribute. Here we summarize results from an integrated project that explored the potential to use observations of seismic anisotropy to interpret lithological and fluid properties (the SAIL project). Our approach links detailed petrofabric analyses of reservoir rocks, laboratory based measurements of ultrasonic velocities in core samples, and reservoir-scale seismic observations. We present results for the Clair field, a Carboniferous–Devonian reservoir offshore Scotland, west of the Shetland Islands. The reservoir rocks are sandstones that are variable in composition and exhibit anisotropy on three length-scales: the crystal, grain and fracture scale.

We have developed a methodology for assessing crystal-preferred-orientation (CPO) using a combination of electron back-scattered diffraction (EBSD), X-ray texture goniometry (XRTG) and image analysis. Modal proportions of individual minerals are measured using quantitative X-ray diffraction (QXRD). These measurements are used to calculate the intrinsic anisotropy due to CPO via Voigt-Reuss-Hill averaging of individual crystal elasticities and their orientations. The intrinsic anisotropy of the rock is controlled by the phyllosilicate content and to a lesser degree the orientation of quartz and feldspar; the latter can serve as a palaeoflow indicator. Our results show remarkable consistency in CPO throughout the reservoir and allow us to construct a mathematical model of reservoir anisotropy. A comparison of CPO-predicted velocities and those derived from laboratory measurements of ultrasonic signals allows the estimation of additional elastic compliance terms due to grain-boundary interactions. The results show that the CPO estimates are good proxies for the intrinsic anisotropy of the clean sandstones. The more micaceous rocks exhibit enhanced anisotropy due to interactions between the phyllosilicate grains. We then compare the lab-scale predictions with reservoir-scale measurements of seismic anisotropy, based on amplitude variation with offset and azimuth (AVOA) analysis and non-hyperbolic moveout. Our mathematical model provides a foundation for interpreting the reservoir-scale seismic data and improving the geological modelling of complex reservoirs. The observed increases in AVOA signal with depth can only be explained with an increase in fracturing beneath the major unit boundaries, rather than a change in intrinsic CPO properties. In general, the style and magnitude of anisotropy in the Clair field appears to be indicative of reservoir quality.
Na+/H+ exchange and pH regulation in the control of neutrophil chemokinesis and chemotaxis
Authors: Hayashi Hisayoshi , Aharonovitz Orit , Alexander R. Todd , Touret Nicolas , Furuya Wendy , Orlowski John , Grinstein Sergio
Published: December 2007

Large proton fluxes accompany cell migration, but their precise role remains unclear. We studied pH regulation during the course of chemokinesis and chemotaxis in human neutrophils stimulated by attractant peptides. Activation of cell motility by chemoattractants was accompanied by a marked increase in metabolic acid generation, attributable to energy consumption by the contractile machinery and to stimulation of the NADPH oxidase and the ancillary hexose monophosphate shunt. Despite the increase in acid production, the cytosol underwent a sizable alkalinization, caused by acceleration of Na+/H+ exchange. The development of the alkalinization mirrored the increase in the rate of cell migration, suggesting a causal relationship. However, elimination of Na+/H+ exchange by omission of external Na+ or by addition of potent inhibitors was without effect on either chemokinesis or chemotaxis, provided the cytosolic pH remained near neutrality. At more acidic levels, cell motility was progressively inhibited. These observations suggest that Na+/H+ exchange plays a permissive role in cell motility but is not required for the initiation or development of the migratory response. Chemokinesis also was found to be exquisitely sensitive to extracellular acidification. This property may account for the inability of neutrophils to access abscesses and solid tumors that have been reported to have inordinately low pH.
Restoration of CREB function ameliorates cisplatin cytotoxicity in renal tubular cells
Authors: Arany Istvan , Herbert Johann , Herbert Zsolt , Safirstein Robert L.
Published: December 2007

We have shown that mouse proximal tubule cells (TKPTS) survive H2O2 stress by activating the cAMP-responsive element binding protein (CREB)-mediated transcription via the canonical EGFR-Ras/ERK pathway. By contrast, cisplatin activates EGFR/Ras/ERK signaling in TKPTS cells yet promotes cell death rather than survival. We now demonstrate that the cisplatin-induced activated EGFR/Ras/ERK signaling cascade fails to activate CREB-mediated transcription even in the presence of phosphorylated CREB. CREB-mediated transcription as well as survival was restored by the histone deacetylase (HDAC) inhibitor trichostatine A (TSA), an effective chemotherapeutic agent. Similar to severe oxidant stress, TSA-mediated survival could be abrogated by inhibition of CREB-mediated transcription. These studies confirm the importance of CREB-mediated transcription in the survival of renal cells subjected to either oxidant- or cisplatin-induced stress. The use of cisplatin and TSA in combined chemotherapy protocols may be an effective strategy to enhance cancer cell death and limit nephrotoxicity.
Sustained hypoxia-induced proliferation of carotid body type I cells in rats
Authors: Wang Z.-Y. , Olson E. B. , Bjorling D. E. , Mitchell G. S. , Bisgard G. E.
Published: December 2007

Sustained hypoxia (SH) has been shown to cause profound morphological and cellular changes in carotid body (CB). However, results regarding whether SH causes CB type I cell proliferation are conflicting. By using bromodeoxyuridine, a uridine analog that is stably incorporated into cells undergoing DNA synthesis, we have found that SH causes the type I cell proliferation in the CB; the proliferation occurs mainly during the first 1–3 days of hypoxic exposure. Moreover, the new cells survive for at least 1 mo after the return to normoxia. Also, SH does not cause any cell death in CB as examined by the terminal deoxynucleotidyl transferase-mediated dUTP-X nick-end labeling assay. Taken together, our results suggest that SH stimulates CB type I cell proliferation, which may produce long-lasting changes in CB morphology and function.
Short-Latency Crossed Inhibitory Responses in Extensor Muscles During Locomotion in the Cat
Authors: Frigon Alain , Rossignol Serge
Published: December 2007

During locomotion, contacting an obstacle generates a coordinated response involving flexion of the stimulated leg and activation of extensors contralaterally to ensure adequate support and forward progression. Activation of motoneurons innervating contralateral muscles (i.e., crossed extensor reflex) has always been described as an excitation, but the present paper shows that excitatory responses during locomotion are almost always preceded by a short period of inhibition. Data from seven cats chronically implanted with bipolar electrodes to record electromyography (EMG) of several hindlimb muscles bilaterally were used. A stimulating cuff electrode placed around the left tibial and left superficial peroneal nerves at the level of the ankle in five and two cats, respectively, evoked cutaneous reflexes during locomotion. During locomotion, short-latency (∼13 ms) inhibitory responses were frequently observed in extensors of the right leg (i.e., contralateral to the stimulation), such as gluteus medius and triceps surae muscles, which were followed by excitatory responses (∼25 ms). Burst durations of the left sartorius (Srt), a hip flexor, and ankle extensors of the right leg increased concomitantly in the mid- to late-flexion phases of locomotion with nerve stimulation. Moreover, the onset and offset of Srt and ankle extensor bursts bilaterally were altered in specific phases of the step cycle. Short-latency crossed inhibition in ankle extensors appears to be an integral component of cutaneous reflex pathways in intact cats during locomotion, which could be important in synchronizing EMG bursts in muscles of both legs.
Pharmacokinetic and Tumor Distribution Characteristics of Temsirolimus in Patients with Recurrent Malignant Glioma
Authors: Kuhn John G. , Chang Susan M. , Wen Patrick Y. , Cloughesy Timothy F. , Greenberg Harry , Schiff David , Conrad Charles , Fink Karen L. , Robins H. Ian , Mehta Minesh , DeAngelis Lisa , Raizer Jeffrey , Hess Kenneth , Lamborn Kathleen R. , Dancey Janet , Prados Michael D. ,   for the North American Brain Tumor Consortium and the National Cancer Institute
Published: December 2007

Purpose: To characterize the pharmacokinetics of temsirolimus and its major metabolite, sirolimus, in patients receiving enzyme-inducing antiepileptic drugs (EIAED) compared with patients receiving non-EIAEDs. An additional objective was to determine whether concentrations of temsirolimus or sirolimus were achieved in brain tumor tissue.

Experimental Design: Patients with recurrent malignant gliomas not receiving EIAEDs initially received temsirolimus weekly at a dose of 250 mg i.v. The dose was subsequently reduced to 170 mg due to intolerable side effects. For patients taking EIAEDs, the starting dose of temsirolimus was 250 mg with standard dose escalation until the maximal tolerated dose was established. Ten whole blood samples were obtained over a period of 24 h after administration of temsirolimus for pharmacokinetic assessments. Patients eligible for cytoreductive surgery received temsirolimus before tumor resection. Whole blood and tumor tissue were obtained for analysis.

Results: Significant differences in the pharmacokinetic variables for temsirolimus and sirolimus were observed between the two patient groups at a comparable dose level of 250 mg. For patients receiving EIAEDs, the systemic exposure to temsirolimus was lower by 1.5-fold. Likewise, peak concentrations and exposure to sirolimus were lower by 2-fold. Measurable concentrations of temsirolimus and sirolimus were observed in brain tumor specimens. The average tissue to whole blood ratio for temsirolimus was 1.43 and 0.84 for sirolimus.

Conclusions: Drugs that induce cytochrome P450 3A4, such as EIAEDs, significantly affect the pharmacokinetics of temsirolimus and its active metabolite, sirolimus. Total exposure to temsirolimus and sirolimus was lower in the EIAED group at the maximum tolerated dose of 250 mg compared with the non-EIAED group at the maximum tolerated dose of 170 mg. However, brain tumor tissue concentrations of temsirolimus and sirolimus were relatively comparable in both groups of patients at their respective dose levels. Correlative analyses of the tissue for the inhibition of the key regulators (p70S6 kinase and 4E-binding protein 1) of mammalian target of rapamycin are necessary to define the therapeutic significance of the altered exposure to temsirolimus.
Fractionated versus Standard Continuous Light Delivery in Interstitial Photodynamic Therapy of Dunning Prostate Carcinomas
Authors: Xiao Zhengwen , Halls Steve , Dickey Dwayne , Tulip John , Moore Ronald B.
Published: December 2007

Purpose: The study aims to compare the standard/continuous light delivery with fractionated light delivery for interstitial photodynamic therapy (PDT) of prostate cancer.

Experimental Design: Dunning R3327 prostate tumor models were established in male syngeneic rats. When tumors reached ∼3,000 mm3, animals were randomized to various treatment groups. Three hours after QLT0074 injection, tumors were illuminated by 690-nm light delivered by a computer-controlled switch, which sequentially directed light to one of the seven optical fibers in cycles. For comparison, tumors were treated with continuous illumination. Tumors treated with light-only served as control. Dynamic contrast-enhanced magnetic resonance imaging was used to monitor tumor perfusion changes before and after PDT.

Results: Tumor response (animal survival) to PDT with fractionated light delivery was PDT dose dependent in both tumor models. Rats bearing anaplastic tumor treated by fractionated light (PDT dose: 1.5 mg/kg QLT0074, 900 J light) had a median survival of 51 days with 25% tumor cures compared with that of 26 days with no tumor cure by continuous illumination (P = 0.015) and 14 days by light-only (P = 0.0001). Rats bearing well-differentiated tumor treated by fractionated light had a median survival of 82 days compared with 65 days by continuous illumination (P = 0.001) and 37 days by light-only. PDT with fractionated light generated a perfusion reduction of 80% compared with 52% for continuous illumination in well-differentiated tumors.

Conclusions: Fractionated light delivery is more effective than continuous light delivery in PDT of prostate cancer (solid tumors). These results warrant further investigation in clinical trials.
Viewing Resistance as Ambivalence: Integrative Strategies for Working With Resistant Ambivalence
Authors: Engle David , Arkowitz Hal
Published: December 2007

Resistance to change is a problem that has long evaded easy solutions. In this article, the authors suggest the value of understanding and working with some forms of resistance as ambivalence. They describe resistant ambivalence in the context of an integrative and multivoiced understanding. A person who is ambivalent possesses a voice that moves toward change and a voice that struggles against change. The authors sought therapy methods that were consistent with the multivoiced integrative understanding of ambivalence and that could be useful in its resolution. Motivational interviewing and the two-chair method are described in this article, along with illustrative case material. These methods share a common spirit and therapist style that is accepting of the client's worldview and creates a strong partnership between the therapist and client. These methods can be used in conjunction with other therapy approaches and have a research base supporting their use.
Noninvasive Quantitation of Drug Concentration in Prostate and Seminal Vesicles: Improvement and Validation With Desipramine and Aspirin
Authors: Cao Ying‐Jun , Caffo Brian , Choi Leena , Radebaugh Christine L. , Fuchs Edward J. , Hendrix Craig W.
Published: December 2007

The accessory glands of the male genital tract are the sites of several major health problems, including benign prostatic hyperplasia, prostate cancer, and human immunodeficiency virus (HIV) transmission. We aimed to validate and improve our noninvasive method for the quantitation of drug concentrations in these physiological subcompartments. Twenty‐seven men were dosed with 100 mg desipramine (a weak base) and 975 mg aspirin (a weak acid) and ejaculated their semen in 1 pass across 5 compartments of a collection device 2.5 hours later. A Bayesian latent‐variable model previously developed by our group was further advanced for the estimation of drug concentrations in prostate and seminal vesicles based on drug and biomarker concentrations in the split ejaculate. Under normality assumptions, desipramine concentration (with 95% credible intervals) in prostate and seminal vesicles were 27 (8.3–52) ng/mL and 7.6 (4.0–11) ng/mL, respectively; salicylate concentration in prostate and seminal vesicles were 2.0 (0.093–6.5) μg/mL, and 9.9 (8.2–12) μg/mL, respectively. The prostate‐to‐seminal vesicles concentration ratio was 0.20 (0.0087–0.75) for salicylate and 3.6 (0.91–9.9) for desipramine. We conclude that our quantitative analysis along with the split ejaculate method is sensitive, reproducible, and applicable for the assessment of pharmacokinetics of the accessory glands of the male genital tract.
Board Up the Windows: The Interactive Effects of Hurricane-Induced Job Stress and Perceived Resources on Work Outcomes
Authors: Hochwarter Wayne A. , Laird Mary Dana , Brouer Robyn L.
Published: December 2007

The authors conducted five studies to examine the interactive effects of hurricane-induced job stress and perceived resources on job satisfaction, job tension, and work effort. The authors hypothesized that heightened hurricane-induced job stress would increase adverse reactions for those with fewer perceived resources. Conversely, the authors expected higher levels of perceived resources to neutralize these effects. Results support the hypothesis across studies. Interestingly, job satisfaction improved for those with high levels of perceived resources as hurricane-induced job stress increased in two studies. The authors discuss theoretical implications for traumatic and general stress research, as well as practice, and provide directions for future research.
Primary Care Trusts
Authors: Abbott Stephen , Smith Richard , Procter Susan , Iacovou Nicci
Published: December 2007

The role of boards in the public sector is unclear, particularly at a time of increased control of services by central government. This paper looks at the case of primary health care organizations, which are responsible for providing or commissioning the health care required by their local populations. Documentary analysis of board papers from 15 such organizations showed that boards are more likely to discuss `second order' functions (finance, governance, administration) than clinical and service issues. In general, they appear to avoid a challenging style in their relationships with officers. Interviews with officers and board members of three organizations found that the possibility that boards might challenge did affect how business is conducted, even though in reality challenge was rare. However, the contribution of boards outside board meetings was also valued, in the work of subcommittees, strategy planning sessions, etc. Though the boards are in no sense representative and their importance in setting strategy and monitoring performance somewhat overshadowed by central government's activity in these areas, they nevertheless do have some authority, which both checks and supports officers.
Nursing Management of Medication Errors
Authors: Luk Leung Andrew , Ng Wai I Milly , Ko Kam Ki Stanley , Vai Ha Ung
Published: December 2007

Medication error is the most common and consistent type of error occurring in hospitals. This article attempts to explore the ethical issues relating to the nursing management of medication errors in clinical areas in Macau, China. A qualitative approach was adopted. Seven registered nurses who were involved in medication errors were recruited for in-depth interviews. The interviews were transcribed and analyzed using content analysis. Regarding the management of patients, the nurses acknowledged the mistakes but did not disclose the incidents to patients and relatives. Concerning management of the nurses involved by senior staff, most participants experienced fairness, comfort and understanding during the process of reporting and investigation. The ethical issues relating to the incidents were discussed, particularly in the Chinese context. There is a need for further study relating to the disclosure of medication incidents to patients and some suggestions were made.
Uncovering the Ethics of Suffering Using a Narrative Approach
Authors: Råholm Maj-Britt
Published: December 2007

The purpose of this article is to portray the ethics of suffering based on the published literature. Narrative use has become common in the fields of nursing education and curriculum development and in the determination of practice competencies. Understanding the ethics of suffering implies a hermeneutic movement between alienation and dedication. To understand the ethical significance of human suffering, the scene of suffering is described through the concepts of: to endure, to struggle, to sacrifice life and health, and to become. To respond, to discover, to approach, to touch and to shape patients' different patterns of life implies responsibility: to see, to affirm their dignity by being, and to express this in ethical words. Narration plays a crucial role in transforming suffering, that is, reformulating patients' stories. It is vital that educators should create a learning environment where students can find the courage and intention to be present and listen to patients' narratives.
Literature Review: ADHD in Adults
Authors: Davidson Megan A.
Published: December 2007

Objective: ADHD presents significant challenges to adults. The current review's goals are (a) to critically examine the current state of knowledge regarding ADHD in adults and (b) to provide clinicians with practice-friendly information regarding assessment, diagnosis, and treatment. Method: Searches of PsycINFO and Medline were conducted, and reference lists from articles and books were searched for additional relevant references. Results/Conclusion: A valid and reliable assessment should be comprehensive and include the use of symptom rating scales, a clinical interview, neuropsychological testing, and the corroboration of patient reports. Specific diagnostic criteria that are more sensitive and specific to adult functioning are needed. In treatment, pharmacological interventions have the most empirical support, with the stimulants methylphenidate and amphetamine and the antidepressants desipramine and atomoxetine having the highest efficacy rates. Scientific research on psychosocial treatments is lacking, with preliminary evidence supporting the combination of cognitive behavioral therapy and medication. (J. of Att. Dis. 2008; 11(6) 628-641)
Barriers to and Facilitators of Walking and Bicycling to School: Formative Results From the Non-Motorized Travel Study
Authors: Ahlport Kathryn N. , Linnan Laura , Vaughn Amber , Evenson Kelly R. , Ward Dianne S.
Published: December 2007

Barriers to and facilitators of walking and bicycling to school were explored through 12 focus groups made up of fourth- and fifth-grade students and their parents who lived near their respective schools. The barriers and facilitators reported by parents and children generally fell into one of three categories: intrapersonal and interpersonal characteristics of parents and children, environmental characteristics of the neighborhood, and environmental and policy characteristics of the school. Findings indicate that a supportive environment is a necessary but insufficient condition to increase walking and biking to school. Initiatives to increase active school travel may need to include multiple levels of intervention to be effective.
Study on electroless Ni–P–ZrO2 composite coatings on AZ91D magnesium alloys
Authors: Song Y.-W. , Shan D.-Y. , Chen R.-S. , Han E.-H.
Published: December 2007

Electroless Ni–P–ZrO2 composite coatings on AZ91D magnesium alloys was developed and their characteristics were investigated. The experimental results showed that the composite coatings were uniform and compact. The hardness of Ni–P–ZrO2 composite coatings reached the maximum value at 350°C heat treatment, and then decreased at 400°C. The nickel phosphor alloys provided solution strengthening and precipitation strengthening, while the ZrO2 nanoparticles provided dispersion hardening, making the composite coatings harder than that of Ni–P coatings. The wear resistance of Ni–P–ZrO2 composite coatings was obviously superior to Ni–P coatings, especially with longer wear time, which can be attributed to the dispersion strengthening and load support effect of ZrO2 in the coatings. The Ni–P–ZrO2 coatings exhibited better corrosion resistance than that of Ni–P coatings owing to codeposition of ZrO2 together with NiP leading to a more compact composite coating.
Deposition and properties of novel microcrystalline Mg alloy coatings
Authors: Bohne Y. , Manova D. , Blawert C. , Störmer M. , Dietzel W. , Mändl S.
Published: December 2007

The present work gives and overview of the deposition, microstructure and corrosion properties of magnesium based supersaturated coatings for the corrosion protection of standard magnesium alloy components. Such protective surface layers with high corrosion resistance were produced using physical vapour deposition techniques at different particle energies, such as magnetron sputtering, ion beam sputtering and cathodic arc deposition. For all these films, a homogeneous microcrystalline morphology with a highly oriented basal texture was observed. The solubility limit of all alloying elements studied was largely extended beyond the thermodynamic equilibrium. Thus highly supersaturated single phase coatings free of localised corrosion and/or microgalvanic corrosion effects between different phases were observed, showing low corrosion rates. Furthermore, the less noble corrosion potentials of some alloying systems compared to standard cast or wrought magnesium alloy substrates allow a cathodic protection of the substrate material by the coating.
Effect of auxiliary preheating of filler wire on dilution in gas metal arc stainless steel surfacing using RSM
Authors: Shahi A. S. , Pandey S. , Gill J. S.
Published: December 2007

Weld surfacing is a process for producing surfaces with good corrosion resistant properties by means of depositing/laying of stainless steels on low carbon steel components with an objective of achieving maximum economy and enhanced life. The aim of the work presented here was to investigate the effect of auxiliary preheating of the solid filler wire in mechanised gas metal arc welding (GMAW) process (using a specially designed torch to preheat the filler wire independently, before its emergence from the torch) on dilution. Four factor five level central composite rotatable design was used to develop relationship for predicting dilution, which enables to quantify the direct and interactive effects of four numeric factors, namely, wire feed rate, arc voltage, welding speed and electrode extension, and one categorical factor, preheat current. Mathematical models developed show that dilution increases with increasing wire feed rate, arc voltage and welding speed, whereas it decreases with increasing electrode extension and preheat current. External preheating of the filler wire resulted in greater contribution of arc energy by resistive heating due to which significant drop in the main welding current values and hence low dilution levels were observed. Numerical optimisation was carried out and the optimal solutions generated indicate that for same levels of dilution, higher deposition rates are achievable in the auxiliary preheating arrangement. Conformity experimental runs show a good agreement with the numerical results.
Coloration and bleaching mechanism of tungsten oxide thin films in different electrolytes
Authors: Sivakumar R. , Shanthakumari K. , Thayumanavan A. , Jayachandran M. , Sanjeeviraja C.
Published: December 2007

In the present paper, the authors report on the electrochromic properties of electron beam evaporated tungsten oxide (WO3) thin films at different electrolytes. The authors observe the better electrochromic performance for the as deposited room temperature prepared films than the higher substrate temperature prepared films and annealed films. In addition, the less reversible coloration was observed for the heavier ion (K+) intercalation/deintercalation than the lighter one (Li+), which may be due to the effect of microstructure of the films, and ion mobility. The possible role of electrochromic performance in the mechanism of film crystallinity has been discussed.
Serglycin proteoglycan deletion induces defects in platelet aggregation and thrombus formation in mice
Authors: Woulfe Donna S. , Lilliendahl Joanne Klimas , August Shelley , Rauova Lubica , Kowalska M. Anna , Åbrink Magnus , Pejler Gunnar , White James G. , Schick Barbara P.
Published: December 2007

Serglycin (SG), the hematopoietic cell secretory granule proteoglycan, is crucial for storage of specific secretory proteins in mast cells, neutrophils, and cytotoxic T lymphocytes. We addressed the role of SG in platelets using SG−/− mice. Wild-type (WT) but not SG−/− platelets contained chondroitin sulfate proteoglycans. Electron microscopy revealed normal α-granule structure in SG−/− platelets. However, SG−/− platelets and megakaryocytes contained unusual scroll-like membranous inclusions, and SG−/− megakaryocytes showed extensive emperipolesis of neutrophils. SG−/− platelets had reduced ability to aggregate in response to low concentrations of collagen or PAR4 thrombin receptor agonist AYPGKF, and reduced fibrinogen binding after AYPGKF, but aggregated normally to ADP. 3H-serotonin and ATP secretion were greatly reduced in SG−/− platelets. The α-granule proteins platelet factor 4, β-thromboglobulin, and platelet-derived growth factor were profoundly reduced in SG−/− platelets. Exposure of P-selectin and αIIb after thrombin treatment was similar in WT and SG−/− platelets. SG−/− mice exhibited reduced carotid artery thrombus formation after exposure to FeCl3. This study demonstrates that SG is crucial for platelet function and thrombus formation. We propose that SG−/− platelet function deficiencies are related to inadequate packaging and secretion of selected α-granule proteins and reduced secretion of dense granule contents critical for platelet activation.