bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of ZnO(0001) surface termination by x‐ray photoelectron spectroscopy at photoemission angles of 0° and 70°
Authors: Zhang L. , Wett D. , Szargan R. , Chassé T.
Published: October 2004

We present an XPS method to determine the termination of the ZnO(0001) surface. By measuring O 1s and Zn 2p3/2 core‐level x‐ray photoelectron spectra at photoemission angles of 0° and 70° and comparing the intensity ratio (IO1s/IZn2p3)θ=0/(IO1s/IZn2p3)θ=70, the Zn and O termination can be distinguished. Calculations show that these two terminations have intensity ratios differing by ∼17%. This difference is not affected by a contamination layer provided that the contamination layer thickness is the same for these two differently terminated surfaces. Although this determination method prefers a clean ZnO(0001) surface (in situ measurement), it seems also feasible for surfaces with known contamination layer thickness (ex situ measurement). We have measured ex situ ZnO(0001)‐Zn, ZnO(000&1macr;)‐O single crystals and an epitaxial ZnO film deposited on Al2O3(0001). The measured intensity ratios of the first two samples agree with the calculated values for a 0.2 and 0.26 nm contamination layer, respectively. The intensity ratio and the O 1s contamination component intensity of the epitaxial ZnO film are close to those of the ZnO(0001)‐Zn single crystal thus pointing at Zn termination of the film. Copyright © 2004 John Wiley & Sons, Ltd.
The effect of within‐industry diversification on firm performance: synergy creation, multi‐market contact and market structuration
Authors: Li Stan Xiao , Greenwood Royston
Published: October 2004

This paper examines the effect of diversification upon intra‐industry performance. We propose that intra‐industry diversification promises three sets of benefits, which, separately and in combination, provide firms with a competitive advantage: synergies arising from economies of scope; premiums from mutual forbearance enabled by multi‐market competition; and efficiencies derived from market structuration. The additive and integrative effects of the first two have not been explored. The benefits of market structuration remain untheorized and thus untested. The test of our theoretical model in the Canadian general insurance industry indicates that mutual forbearance provides advantage under specified conditions, that market structuration also provides advantages, but that diversification per se does not. Copyright © 2004 John Wiley & Sons, Ltd.
Are more resources always better for growth? Resource stickiness in market and product expansion
Authors: Mishina Yuri , Pollock Timothy G. , Porac Joseph F.
Published: October 2004

We examine how managerial growth logics combine with financial and human resource slack to influence the short‐term revenue growth of a sample of 112 manufacturing firms drawn from a unique database provided by the Ewing Marion Kauffman Foundation. Our results provide evidence that firms pursuing product expansion logics generally grow more slowly than firms that are not expanding their product base, but that financial slack positively moderates this relationship. We also find that human resource slack enhances short‐term market expansion, but slows down short‐term product expansion. We discuss the implications of these results for resource‐based views of growth. Copyright © 2004 John Wiley & Sons, Ltd.
Nanowires for Integrated Multicolor Nanophotonics
Authors: Huang Yu , Duan Xiangfeng , Lieber Charles M.
Published: October 2004

Nanoscale light‐emitting diodes (nanoLEDs) with colors spanning from the ultraviolet to near‐infrared region of the electromagnetic spectrum were prepared using a solution‐based approach in which emissive electron‐doped semiconductor nanowires were assembled with nonemissive hole‐doped silicon nanowires in a crossed nanowire architecture. Single‐ and multicolor nanoLED devices and arrays were made with colors specified in a predictable way by the bandgaps of the III–V and II–VI nanowire building blocks. The approach was extended to combine nanoscale electronic and photonic devices into integrated structures, where a nanoscale transistor was used to switch the nanoLED on and off. In addition, this approach was generalized to hybrid devices consisting of nanowire emitters assembled on lithographically patterned planar silicon structures, which could provide a route for integrating photonic devices with conventional silicon microelectronics. Lastly, nanoLEDs were used to optically excite emissive molecules and nanoclusters, and hence could enable a range of integrated sensor/detection “chips” with multiplexed analysis capabilities.
Dynamic accumulation of neutrophils in lungs and visceral organs during early abdominal sepsis in the pig
Authors: Malmros Christer , Holst Elisabeth , Hansson Lars , Mårtensson Lena , Thörne Johan
Published: October 2004

Activation and accumulation of polymorphonuclear leukocytes (PMNs, neutrophils) in the lungs is considered an important mechanism in the pathogenesis of pulmonary dysfunction in association with sepsis. It probably constitutes only part of a general cellular response; and a corresponding reaction has been implicated in other organs during sepsis (e.g., the liver). In this experiment a model was developed that allows study of the dynamic PMN reaction in the lungs and visceral organs during early abdominal sepsis. The animals were divided into two groups. In the septic group (n=8) a bacterial challenge was attempted through the intraperitoneal administration of Escherichia coli (1 x 1011/kg). Five animals served as controls. All animals in the septic group developed bacteremia, leukopenia, and a hypodynamic circulatory response. PMNs were selectively labeled with 111In‐oxine. The activity over the organs was followed dynamically with a gamma camera. The animals subjected to peritonitis exhibited a significant increase in 111In‐oxine activity (i.e., neutrophil trapping) in the lungs, compared to the controls at 40 minutes and onward during the observation period. A similar picture was seen over the liver and abdomen, with significance after 70 minutes. The findings in this study indicate that accumulation of PMNs is an early phenomenon not only in the lungs but also in the liver during the development of sepsis. The present model offers possibilities for further studies of the cellular reactions during sepsis.
Simple method of hyperthermo‐chemo‐hypoxic isolated liver perfusion for hepatic metastases
Authors: Horikawa Masato , Nakajima Yoshiyuki , Kido Kiyoshi , Ko Saiho , Ohashi Kazuo , Nakano Hiroshige
Published: October 2004

As a regional therapy for hepatic malignancy, we developed a simple method of isolated liver perfusion (hyperthermo‐chemo‐hypoxic). In the present study, the influence of this method on the hepatic tissue and other organs was experimentally evaluated and applied it to seven patients. Experimentally, all dogs survived without hepatic insufficiency and systemic toxicity. Clinically, one patient died on postoperative day 14 of hepatic failure. The reason was that liver temperature reached 43°C, which seemed to be the maximum limit for thermal toxic effect to the human liver. The other six patients well tolerated the perfusion with mild increases of serum aminotransferase and total bilirubin levels and decreases of hepaprastin levels. Serum aminotransferase and total bilirubin and hepaprastin levels returned to normal levels by postoperative day 14. There were no significant differences between the isolated liver perfusion group (n=7) and hepatectomy‐only group (n=27). Six patients were discase‐free during the observation period after the perfusion. This system is a simple, useful method for treating patients with metastatic cancer limited to the liver.
Early stage gastric lymphoma: Is operation essential?
Authors: Tanaka Yasuhiro , Takao Tetsuto , Watanabe Hirotoshi , Kido Tetsuo , Ogawa Noritsugu , Iwase Kazuhiro , Sunada Shouji , Sando Kinya , Kawamoto Seiichi , Koto Kiyoshi , Satani Minoru , Ono Norio
Published: October 2004

to assess the efficacy of primary chemotherapy for treatment of early stage patients with gastric lymphoma, multiple agent chemotherapy was given to patients prior to surgery. Five patients with stages IE and IIE of primary gastric lymphoma (54–65 years of age; three men, two women) were treated with multiple agent chemotherapy prior to gastric resection. In all patients the diagnosis was established by endoscopic biopsy. Two patients had stage IE disease, and three had stage IIE. Histopathologically, there was one diffuse large cell lesion and four diffuse medium cell tesions. All patients received two cycles of VEPA every 4 weeks. On the 16th to 44th day after completion of chemotherapy, total gastrectomy, systematic dissection of regional lymph nodes with resection of the caudal pancreas, and splenectomy were performed. Swelling of the regional lymph nodes was noted in four cases. In all five cases, histologic findings revealed no residual cells of malignant lymphoma in the resected specimen. None of the patients had no evidence of recurrence at 12 to 40 months after surgery. Primary chemotherapy alone thus resulted in the disappearance of malignant cells in stage IE/IIE gastric lymphoma. Our reatment of early stage gastric lymphoma.
Local versus general anesthesia for Shouldice repair of the inguinal hernia
Authors: Peiper Christian , Töns Christian , Schippers Ekkehard , Busch Frank , Schumpelick Volker
Published: October 2004

Since February 1992 local anesthesia (LA) has been used routinely for repair of inguinal hernias at our surgical department. All patients undergoing Shouldice repair of primary uncomplicated inguinal hernia between January 1990 and March 1993 were analyzed retrospectively concerning the need for analgesics, length of stay in hospital, and rate of complications. In addition 50 patients after LA and 50 patients after general anesthesia underwent prospective pain analysis using a visual analogous score and spirometric tests (FEV1 and peak flow). After LA we found less need of analgesics, shorter hospital stays, and fewer complications. The pain level was lower, and ventilatory function was less affected. Repair of the inguinal hernia using LA is a safe method to lower the risk of the operation and to improve the patient's comfort without increasing complications.
Results of mandatory exploration for penetrating neck trauma
Authors: Apffelstaedt Justus P. , Med M. , Müller Richard
Published: October 2004

Management of penetrating wounds to the neck remains controversial despite decades of discussion in the literature. We assessed 393 consecutive stab wounds penetrating the platysma operated at our trauma service between January 14, 1991 and September 30, 1992 to evaluate our policy of mandatory neck exploration (NE). Injury to the common (n=19 cases), external (n=7), internal carotid (n=5), innominate (n=2), subclavian (n=20), vertebral (n=12), facial (n=2), and intercostal (n=2) arteries; the external (n=36), internal (n=65), subclavian (n=20), and innominate (n=4) veins; the pharynx/esophagus (n=21); and the trachea (n=28) was considered a positive NE (n=167). 226 NEs were negative. Except for hemiparesis and bruit, the presence of clinical signs (shock, active hemorrhage, hematoma, surgical emphysema, dysphagia, blowing wound) did not predict a positive NE. Clinical signs were absent in 30% of positive NEs and in 58% of negative NEs. Complications of positive NE included wound infection (n=7 cases), chyle drainage (n=6), cerebellar stroke (n=1), pneumonitis (n=8), reoperation for recurrent hemorrhage (n=1), subclavian artery graft occlusion (n=1), bronchopleural fistula (n=1), and cerebrospinal fluid leak (n=1). Negative NEs were complicated by a wound infection in four cases and pneumonitis in one case. The mean hospital stay was 4.3 days for those with a positive NE and 1.5 days for those with a negative NE. Clinical signs are of no help in determining whether a stab wound to the neck has led to potentially life‐threatening injury. Mandatory NE saves unnecessary invasive diagnostic studies, is associated with negligible morbidity, and incurs only a short hospital stay.
Intraluminal shunt for the thoracic aorta: Spinal cord and visceral blood flow in acute studies
Authors: Van Voorst Steven J. , Rustom Samir , Pate James W. , Maijub Amado G. , Leffler Charles W.
Published: October 2004

Aortic cross‐clamping during surgery of the thoracic aorta may result in paraplegia or kidney failure. Difficulties associated with external shunts and bypasses have limited their use. Therefore we compared intraluminal shunting to the nonshunting method of repair in neonatal pigs. Blood flow to the spinal cord and viscera was measured with radiolabeled microspheres before, during, and after thoracic aortic cross‐clamping or shunting. Two no‐shunt groups were studied: One group was clamped distal to the left subclavian artery for 30 minutes and the other for 1 hour. In the intraluminal shunt group, a shunt was placed in the aorta just below the ligamentum arteriosum for 1 hour; it was then removed and the aorta repaired. In the no‐shunt groups, there was virtually no blood flow to the lower cord and viscera during the cross‐clamp period. Hyperemia of the lower thoracic and lumbar cord occurred in the no‐shunt 30‐minute group 15 minutes after clamp removal. In the no‐shunt 60‐minute group, flow initially returned to the lumbar cord but then declined; and after 1 hour of reperfusion it was significantly lower than baseline. Renal blood flow was even more severely affected in the no‐shunt 60‐minute group, with minimal recovery during the reperfusion period. In the intraluminal shunt group baseline spinal cord and visceral blood flow were maintained during thoracic aortic cross‐clamping, without the problems associated with extracorporeal circulation.
Prevention of gastric ulcer or acute gastric mucosal lesions accompanying bleeding after abdominal aortic aneurysm surgery
Authors: Konno Hiroyuki , Kaneko Hiroshi , Maruo Yuji , Tatuo Tanaka , Nobuhiko Nishino , Nakamura Satoshi , Baba Shozo
Published: October 2004

We have previously reported that the decrease in gastric mucosal blood flow (GMBF) and consumption coagulopathy (CC) mainly contribute to the development of postoperative bleeding in the upper gastrointestinal (GI) tract in patients with abdominal aortic aneurysm (AAA). In the present study, we investigated whether our treatment for patients with low GMBF or CC effectively prevented postoperative gastric bleeding induced by gastric ulcer or acute gastric mucosal lesion. Preoperative endoscopic examinations in 66 patients with AAA and 60 patients with arteriosclerosis obliterance (ASO) revealed that 50.0% of AAA and 16.6% of ASO patients had accompanying gastric ulcer or multiple erosions. In 38 AAA and 36 ASO patients, GMBF was measured using a laser Doppler flowmeter through an endoscope. The GMBF was severely impaired in AAA patients and moderately impaired in ASO patients. The platelet counts and fibrinogen levels were significantly decreased in these 38 AAA patients compared with controls. Furthermore, fibrinogen degeneration product (FDP) levels in 36.8% of AAA patients were more than 20 μg/dl. Based on these findings, patients with low GMBF were treated postoperatively with H2‐blocker, and patients with CC were treated preoperatively with heparin. After these treatments, only 1 of 38 AAA patients developed postoperative upper GI tract bleeding and could be treated conservatively after 1988, whereas in prior years post‐operative upper GI tract bleeding developed in 7 of 112 patients, three of whom required emergency surgery.
Vascular involvement in Behçet's isease: 8‐Year audit
Authors: Kuzu Mehmet A. , Özaslan Cihangir , Köksoy Cüneyt , Gürler Aysel , Tüzüner Altan
Published: October 2004

Behçet's disease is a multisystemic disorder characterized by cecurrent ulcers of the mouth and genitalia and relapsing iritis. Four types of vascular lesion are recognized in Behçet's disease: arterial occlusions, aneurysms, venous occlusions, and variceal development. The incidence of vascular involvement reported in the literature ranges from 7% to 29%. The aim of this study was to determine the rate of vascular involvement in Behçet's disease at our hospital between 1983 and 1992. Of 1200 patients with Behçet's disease, 173 (14.4%) had venous manifestations and 19 (1.6%) had arterial manifestations (in some patients more than one organ was involved). In the group of patients with venous manifestations, there were 154 (12.8%) with venous thrombosis, 17 (1.4%) with vena cava superior syndrome, 5 (0.4%) with inferior vena cava syndrome, 5 (0.4%) with varices, 2 with upper extremity venous thrombosis, 1 with internal jugular vein thrombosis, 1 with cavernous sinus thrombosis, and 1 with hepatic vein thrombosis. In the arterial manifestation group there were 7 femoral, 3 abdominal, 3 popliteal, 2 iliac, 2 pulmonary, 1 axillary, and 1 carotid artery aneurysm as well as 3 arterial occlusions. We concluded that vascular surgeons dealing with young adults should bear Behçet's disease, an uncommon clinical entity, in mind.
Double transfection improves small interfering RNA‐induced thrombin receptor (PAR‐1) gene silencing in DU 145 prostate cancer cells
Authors: Liu Jian , Schuff-Werner Peter , Steiner Michael
Published: October 2004

The efficiency of small interfering RNA (siRNA)‐induced gene knockdown is hampered by low transfection efficiency. We established a novel and simple double transfection method using specific siRNA duplexes targeted against human thrombin receptor PAR‐1 in DU 145 prostate cancer cells. The initial siRNA transfection of cell suspensions followed by re‐transfection of adherent cells on the following day resulted in undetectable PAR‐1 mRNA and absent receptor protein. PAR‐1 mRNA expression was silenced for up to five days. Functional studies showed that PAR‐1 gene silencing in DU 145 cells abolished the modulating effects of thrombin on cell adhesion to the extracellular matrix proteins, fibronectin and laminin, thus demonstrating the essential role of PAR‐1 in mediating thrombin effects on DU 145 cell adhesion.
A new type of protein methylation activated by tyrphostin A25 and vanadate
Authors: Miranda Tina Branscombe , Lowenson Jonathan D. , Clarke Steven
Published: October 2004

It has been reported that S‐adenosylmethionine‐dependent protein methylation in rat kidney extracts can be greatly stimulated by tyrphostin A25, a tyrosine kinase inhibitor. We have investigated the nature of this stimulation. We find that addition of tyrphostin A25, in combination with the protein phosphatase inhibitor vanadate, leads to the stimulation of methylation of polypeptides of 64, 42, 40, 36, 31, and 15 kDa in cytosolic extracts of mouse kidney. The effect of tyrphostin appears to be relatively specific for the A25 species. The enhanced methylation does not represent the activity of the families of protein histidine, lysine or arginine methyltransferases, nor that of the l‐isoaspartyl/d‐aspartyl methyltransferase, enzymes responsible for the bulk of protein methylation in most cell types. Chemical and enzymatic analyses of the methylated polypeptides suggest that the methyl group is in an ester linkage to the protein. In heart extracts, we find a similar situation but here the stimulation of methylation is not dependent upon vanadate and an additional 18 kDa methylated species is found. In contrast, little or no stimulation of methylation is found in brain or testis extracts. This work provides evidence for a novel type of protein carboxyl methylation reaction that may play a role in signaling reactions in certain mammalian tissues.
Tyrosine dephosphorylation of STAT3 in SARS coronavirus‐infected Vero E6 cells
Authors: Mizutani Tetsuya , Fukushi Shuetsu , Murakami Masaaki , Hirano Toshio , Saijo Masayuki , Kurane Ichiro , Morikawa Shigeru
Published: October 2004

Severe acute respiratory syndrome (SARS) has become a global public health emergency. p38 mitogen‐activated protein kinase (MAPK) and its downstream targets are activated in SARS coronavirus (SARS‐CoV)‐infected Vero E6 cells and activation of p38 MAPK enhances the cytopathic effects of SARS‐CoV infection. In addition, weak activation of Akt cannot prevent SARS‐CoV infection‐induced apoptosis in Vero E6 cells. In the present study, we demonstrated that signal transducer and activator of transcription (STAT) 3, which is constitutively phosphorylated at tyrosine (Tyr)‐705 and slightly phosphorylated at serine (Ser)‐727 in Vero E6 cells, was dephosphorylated at Tyr‐705 on SARS‐CoV infection. In addition to phosphorylation of p38 MAPK in virus‐infected cells, other MAPKs, i.e., extracellular signal‐regulated kinase (ERK) 1/2 and c‐Jun N‐terminal kinase (JNK), were phosphorylated. Although inhibitors of ERK1/2 and JNK (PD98059 and SP600125) had no effect on phosphorylation status of STAT3, inhibitors of p38 MAPK (SB203580 and SB202190) partially inhibited dephosphorylation of STAT3 at Tyr‐705. Tyr‐705‐phosphorylated STAT3 was localized mainly in the nucleus in mock infected cells, whereas STAT3 disappeared from the nucleus in virus‐infected cells. As STAT3 acts as an activator of transcription in the nucleus, these results suggest that STAT3 lacks its activity on transcription in SARS‐CoV‐infected Vero E6 cells.
The HECT E3 ubiquitin ligase Rsp5 is important for ubiquitin homeostasis in yeast
Authors: Krsmanović Tamara , Kölling Ralf
Published: October 2004

The HECT E3 ubiquitin ligase Rsp5, a yeast member of the Nedd4 family, has been implicated in many different aspects of cell physiology. Here, we present evidence that Rsp5 function is important for ubiquitin homeostasis. Several observations suggest that ubiquitin is limiting in the rsp5‐1 mutant. Reduced synthesis of ubiquitin appears to contribute to ubiquitin depletion. A transient inhibition of general protein synthesis is observed in a wildtype strain upon heat‐shock. While the wildtype cells quickly recover from this transient arrest, the rsp5‐1 cells remain arrested. This suggests that Rsp5 is important for recovery from heat‐induced protein synthesis arrest. Our results suggest that rsp5 phenotypes should be interpreted with caution, since some of the phenotypes could be simply the result of ubiquitin limitation.
Structure of the mitochondrial β‐ketoacyl‐[acyl carrier protein] synthase from Arabidopsis and its role in fatty acid synthesis
Authors: Olsen Johan G. , Rasmussen Anne V. , von Wettstein-Knowles Penny , Henriksen Anette
Published: October 2004

Mitochondrial fatty acid synthesis is catalyzed by a dissociated fatty acid synthase similar to those of plant plastids and bacteria. The crystal structure of a mitochondrial β‐ketoacyl‐[acyl carrier protein] synthase (mtKAS), namely that from Arabidopsis thaliana, has been determined for the first time. This enzyme accomplishes the vital condensation steps in constructing fatty acid carbon skeletons. The product profile of mtKAS is unusual in that C8 and C14–16 fatty acyl chains predominate. An enzyme architecture that likely is the basis for the observed bimodal profile of mtKAS products can be derived from the shape of the acyl binding pocket.
Consumption of nitric oxide by endothelial cells: Evidence for the involvement of a NAD(P)H‐, flavin‐ and heme‐dependent dioxygenase reaction
Authors: Schmidt Kurt , Mayer Bernd
Published: October 2004

In the present study, we investigated the mechanism of nitric oxide (NO) inactivation by endothelial cells. All experiments were performed in the presence of superoxide dismutase to minimize the peroxynitrite reaction. Incubation of the NO donor diethylamine/NO adduct with increasing amounts of intact cells led to a progressive decrease of the NO concentration, demonstrating a cell‐dependent consumption of NO. In cell homogenates, consumption of NO critically depended on the presence of NADPH or NADH and resulted in the formation of nitrate. Both NO consumption and nitrate formation were largely inhibited by the heme poisons NaCN and phenylhydrazine as well as the flavoenzyme inhibitor diphenylene iodonium. Further characterization of this NO consumption pathway suggests that endothelial cells express a unique membrane‐associated enzyme or enzyme system analogous to the bacterial NO dioxygenase that converts NO to nitrate in a NAD(P)H‐, flavin‐ and heme‐dependent manner.
SHP2 binds catalase and acquires a hydrogen peroxide‐resistant phosphatase activity via integrin‐signaling
Authors: Yano Sumio , Arroyo Nelly , Yano Noriko
Published: October 2004

Here, we examined whether catalase binds SHP2 and alters SHP2 susceptibility to H2O2. Our results indicated that serum and fibrinogen commonly evoked catalase binding to SHP2 in HeLa and A549 cells in a herbimycin‐A and TNFα sensitive manner. Expression of active catalase nearly 15‐fold over control levels in tet‐off HeLa cells substantially increased the SHP2 binding, and the catalase‐associated SHP2 displayed significantly high phosphatase activities with a H2O2‐resistance compared to those with little catalase. Site‐directed mutagenesis at 280 abolished the binding capability of catalase to SHP2–SH2 in vitro. These results suggest that catalase‐280pYIQV binds SHP2 via integrin‐signaling to increase a H2O2‐resistant SHP2 activity.
The Sauve–Kapandji Procedure and the Darrach Procedure for Distal Radio–Ulnar Joint Dysfunction after Colles’ Fracture
Authors: GEORGE M. S. , KIEFHABER T. R. , STERN P. J.
Published: October 2004

This retrospective study evaluated the results of the Darrach procedure and the Sauve–Kapandji procedure for the treatment of distal radio–ulnar joint derangement following malunion of dorsally displaced, unstable, intraarticular fractures of the distal radius in patients under 50 years of age. Twelve of 18 possible patients in the Sauve–Kapandji group completed the disabilities of the arm, shoulder, and hand survey at a mean of 4 years postoperatively and nine of the 18 returned for a follow-up examination at a mean of 2 years. Twenty-one of 30 possible patients in the Darrach group completed the disabilities of the arm, shoulder, and hand survey at a mean of 6 years postoperatively and 13 of these 30 returned for follow-up examination at a mean of 4 years. The Darrach procedure and the Sauve–Kapandji procedure yielded comparable and unpredictable results with respect to both subjective and objective parameters.
The transfer of 73As, 109Cd and 203Hg to the milk and tissues of dairy cattle
Authors: CROUT N. M. J. , BERESFORD N. A. , DAWSON J. M. , SOAR J. , MAYES R. W.
Published: October 2004

By a variety of exposure routes it is possible that the toxic heavy metals cadmium, arsenic and mercury could enter the diet of farm animals and hence contaminate food products derived from those animals. Therefore, there is a need to be able to assess the likely levels of contamination in animal tissues if exposed to contaminated feed and also to estimate how rapidly an animal will decontaminate once the source of contamination is removed from the feed. The development of dynamic models to predict changes in the degree of heavy metal contamination in tissues of ruminants have been hindered by the lack of data on the transfer and excretion rates of these metals from tissues. A study is described during which dairy cows were given a single intraruminal administration of 109Cd, 73As and 203Hg and measurements made of the subsequent concentrations of the radioisotopes in body tissues and milk. The resultant data were used to adapt previously developed compartment models describing the behaviour of the metals in sheep for use with dairy cows. Two changes were made to the sheep models: (i) a new excretion route was included to describe transfer to milk; (ii) the rate coefficients (with the exception of those involving gut absorption and transfer) were adjusted according to the ratio of the metabolic live-weights (live-weight (kg)0·75) of the sheep to that of the cattle. The models predicted levels of the metals in the cattle tissues and milk reasonably well.
Active immunization against adrenocorticotrophic hormone (ACTH) in grazing lambs suppresses the immune response to a GnRH antigen but does not alter growth
Authors: PAULL D. , RIGBY R. , THOMPSON J. , WYNN P.
Published: October 2004

This experiment examined the effects of immunizing against ACTH (adrenocorticotrophic hormone) and GnRH (hypothalamic peptide gonadotrophic releasing hormone) on growth and carcase composition of entire ram lambs from 6 to 35 weeks of age. There were four experimental groups (each of 17 animals) in a 2×2 factorial design: (1) a non-immunized control group, (2) immunized against ACTH, (3) immunized against GnRH and (4) immunized against both antigens. After booster injections, experimental lambs exhibited antibody titres to the two antigens presented, resulting in significantly lower cortisol and testosterone levels (P<0·001) in peripheral blood. The fall in blood cortisol levels in response to ACTH immunization was later matched by a similar decline in control animals to a point where they were not different.

In GnRH-immunized animals, antibodies disrupted the pituitary-gonadal axis, thereby impacting severely on testes development in growing lambs to the degree that by day 119 their testes were smaller than at the commencement of the experiment. Towards the end of the growth phase of the animals, GnRH-immunized lambs had significantly lower body weights at day 189 (P<0·05) and day 204 (P<0·01) while ACTH-immune lambs were not different in weight from control animals. Also, GnRH-immunized lambs were found to have greater GR measurement (P<0·05). Although ACTH immunization was capable of lowering cortisol for a brief period during the current experiment, the results were variable and detrimental to the efficacy of the immuno-castration vaccine (GnRH).
The promotional state and Canada's Juno Awards
Authors: YOUNG DAVID
Published: October 2004

The scholarly literature on popular music has rarely addressed music awards shows and the role of the state with regard to popular music. In an effort to deepen what is known about both sets of issues, this article utilises the concept of a promotional state to examine Canada's Juno Awards. A promotional state employs state intervention to support domestic popular music, and the promotional state in Canada has been connected to the Junos in three ways (through Canadian content regulations, public broadcasting and government funding). The historical, political economic analysis in the article considers how the role of the promotional state has undergone changes with regard to the Juno Awards. There has been some ‘hollowing out’ of the promotional state's role since the Junos began in 1971, but the article contends that (in the interests of private capital) the role of this state has continued and even increased in some respects.
Imageforschung mit Kognitiven Karten: Die Landschaft der Fernsehsender in der Wahrnehmung der Zuschauer/innen
Authors: Läge Damian , Kälin Stephan
Published: October 2004

Zusammenfassung. Kognitive Karten bilden die strukturelle Sichtweise ab, die eine Gruppe von Personen von einem Ausschnitt der Welt besitzt. Insofern ist diese psychologische Konzeption geeignet, den stärker soziologisch orientierten Fragebogenansatz in der Imageforschung zu ergänzen. Am Beispiel der in der Schweiz empfangbaren deutschsprachigen Fernsehsender wird der methodische Ansatz Multidimensionaler Skalierung exemplarisch auf die Imageforschung im Bereich der Medien angewendet. Zwei Studien arbeiten die strukturellen Merkmale des von den Zuschauer/inne/n wahrgenommenen Gesamtfeldes heraus und ermöglichen so die Betrachtung jedes einzelnen Senders in seiner relationalen Position zum Gesamt. Die wahrgenommene Senderlandschaft erweist sich als geprägt einerseits von der Dichotomie öffentlich-rechtlicher und privat finanzierter Sender, andererseits durch prototypische Spartensender.
Subduction zone anisotropy beneath Corvallis, Oregon: A serpentinite skid mark of trench‐parallel terrane migration?
Authors: Park Jeffrey , Yuan Huaiyu , Levin Vadim
Published: October 2004

We studied the back azimuth dependence of Ps converted phases at GSN station COR (Corvallis, Oregon) using broadband P receiver functions computed from 602 teleseismic earthquakes. The amplitudes and polarities of the transverse Ps phases are largely two‐lobed, which indicates anisotropy with a tilted symmetry axis. A double‐peaked Ps conversion at 4.5–6.5 s delay has the moveout of a dipping slab but is not consistent with simple deflection of the Ps converted phase by the dipping interface. A polarity flip on the transverse receiver function near north‐south back azimuth indicates an anisotropic symmetry axis aligned north‐south, far from the convergence direction (N68°E). The Ps phase is modeled using reflectivity synthetics with a highly anisotropic layer of depressed wave speed (VP ∼ 6.0–6.5 km/s) near 40 km depth, at the slab interface with the overriding North American plate. One‐dimensional modeling suggests 10% anisotropy in the supraslab layer, with a slow symmetry axis oriented N5°W at a 60° tilt from the vertical. Adjustments for the effect of slab interface dip on Ps amplitude suggest a somewhat lower 7% anisotropy. We infer a thin (∼7 km) anisotropic detachment zone for the northward slippage of the Siletz forearc terrane along the top of the descending slab, a motion consistent with GPS measurements and models of regional lithospheric dynamics. Serpentinite is a likely constituent for the deep anisotropic layer, owing to its reduced VP and high Poisson ratio. The ductile rheology and hydrated composition of serpentinite make it a plausible lithology for a mechanical detachment zone.
Source inversion of intensity patterns of earthquakes: A destructive shock in 1936 in northeast Italy
Authors: Sirovich Livio , Pettenati Franco
Published: October 2004

We demonstrate that it is possible to retrieve geometric and kinematic information about the source of a destructive past earthquake by inverting its regional macroseismic intensity patterns. In fact, in the case study the inversion results agree with the seismological instrumental measurements of the 1930s and with neotectonic evidence. This leads to the hope that more knowledge about preinstrumental events can be obtained: a key toward improving the calculation of seismic hazard, mostly in the Old World. After validating our technique on the 1987 Whittier Narrows, California, earthquake [Pettenati and Sirovich, 2003;Gentile et al., 2004] we achieve the present results by investigating an earthquake that happened in 1936 in northeast Italy. The automatic inversions were performed by using a simplified formula for body waves that radiate from a linear source. The inversion shows two minima on the hypersurface of the minimum residuals (calculated – observed intensity at all sites) in the multiparameter model space. These two minimum variance source models resemble the two auxiliary planes of the same theoretical fault plane solution, similar to that given by the standard use of the firstPwave arrivals. The present result encourages us to treat more cases and to explore new inversion techniques for quantitatively treating the intensity patterns of earthquakes because, at least in some cases, they carry geometric and kinematic information about their source.
Thermal isolation of Campbell Plateau, New Zealand, by the Antarctic Circumpolar Current over the past 130 kyr
Authors: Neil Helen L. , Carter Lionel , Morris Michele Y.
Published: October 2004

Campbell Plateau occupies a key position in the southwest Pacific sector of the Southern Ocean. The plateau confines and steers the Antarctic Circumpolar Current (ACC) along its flanks, isolating the Subantarctic plateau from cold polar waters. Oxygen and carbon isotope records from Campbell Plateau cores provide new records of water mass stratification for the past 130 kyr. During glacial climes, strengthening of the Subantarctic Front (SAF) caused waters over the plateau flanks to be deeply mixed and ∼3°C cooler. Waters of the plateau interior remained stratified and isolated from the cold southern waters. In the west, waters cooled markedly (∼4°C) owing to reduced entrainment of Tasman Sea water. Marked cooling also occurred north of Campbell Plateau under increased entrainment of polar water by a branch of the SAF. The ACC remained along the flanks of Campbell Plateau during the last interglacial, when interior waters were stratified and warmer by ∼1°C than now.
Glacial‐interglacial modulation of the marine nitrogen cycle by high‐latitude O2 supply to the global thermocline
Authors: Galbraith Eric D. , Kienast Markus , Pedersen Thomas F. , Calvert Stephen E.
Published: October 2004

An analysis of sedimentary nitrogen isotope records compiled from widely distributed marine environments emphasizes the global synchrony of denitrification changes and provides evidence for a strong temporal coupling of these variations to changes in nitrogen fixation as previously inferred. We explain the global coherence of these records by a simple physical control on the flux of dissolved oxygen to suboxic zones and the coupling to fixation via the supply of phosphorus to diazotrophs in suitable environments. According to our hypothesis, lower glacial‐stage sea surface temperature increased oxygen solubility, while stronger winds in high‐latitude regions enhanced the rate of thermocline ventilation. The resultant colder, rapidly flushed thermocline lessened the spatial extent of denitrification and, consequently, N fixation. During warm periods, sluggish circulation of warmer, less oxygen rich thermocline waters caused expansion of denitrification zones and a concomitant increase in N fixation. Local fluctuations in export productivity would have modulated this global signal.
The melt anomaly of 2002 on the Greenland Ice Sheet from active and passive microwave satellite observations
Authors: Steffen K. , Nghiem S. V. , Huff R. , Neumann G.
Published: October 2004

Active and passive microwave satellite data are used to map snowmelt extent and duration on the Greenland ice sheet. The passive microwave (PM) data reveal the extreme melt extent of 690,000 km2 in 2002 as compared with an average extent of 455,000 km2 from 1979–2003. A statistical analysis of the melt time series affirms an increased melt extent earlier in the melt season. The QuikSCAT (QSCAT or AM) analysis for 1999 to 2004 confirms the extreme melt situation in 2002. QSCAT data show a significant increase in melt season length over several areas in 2003. SSM/I and QSCAT melt data reveal that the later detects melt earlier and is more sensitive to surface melt. QSCAT detects an earlier stage of melt and SSM/I detects a later stage of melt. The SSM/I XGPR melt extent is approximately confined to the QSCAT melt areas experiencing 2 weeks or more of melting time.
Strato‐mesospheric measurements of carbon monoxide with the Odin Sub‐Millimetre Radiometer: Retrieval and first results
Authors: Dupuy É. , Urban J. , Ricaud P. , Le Flochmoën É. , Lautié N. , Murtagh D. , De La Noë J. , El Amraoui L. , Eriksson P. , Forkman P. , Frisk U. , Jégou F. , Jiménez C. , Olberg M.
Published: October 2004

The Sub‐Millimetre Radiometer (SMR) aboard the Odin satellite has been measuring vertical profiles of atmospheric trace gases since August 2001. We present the inversion methodology developed for CO measurements and the first retrieval results. CO can be retrieved from a single scan measurement throughout the middle atmosphere, with a typical resolution of ∼3 km and a relative error of ∼10% to ∼25%. Retrieval results are evaluated through comparison with data from the Whole Atmosphere Community Climate Model (WACCM) and observations of the Improved Stratospheric and Mesospheric Sounder (ISAMS) on board the Upper Atmospheric Research Satellite (UARS). Considering the large natural variability of CO, the SMR retrievals give good confirmation of the WACCM results, with an overall agreement within a factor of 2. ISAMS abundances are higher than SMR mixing ratios by a factor of 5–10 above 0.5 hPa from ∼80°S to ∼50°N.
Persistent drainage migration in a numerical landscape evolution model
Authors: Pelletier Jon D.
Published: October 2004

Numerical landscape evolution models driven by uniform vertical uplift often develop a static drainage network and a precise balance between uplift and erosion. Small‐scale physical models of uplifting drainage basins, however, continually reorganize by ridge migration and do not reach an ideal steady state. Here I show that the presence or absence of persistent drainage migration in a bedrock numerical landform evolution model depends on the flow‐routing algorithm used to determine upstream contributing area. The model version that uses steepest‐descent routing achieves an ideal steady state, while the model version that uses bifurcation routing results in continually‐evolving drainage basins, even under conditions of uniform vertical uplift, bedrock erodibility, precipitation, and landsliding threshold. This result suggests that persistent drainage migration can occur by erosional processes alone. This result has important implications for numerical‐modeling methodology, our understanding of the natural variability of landform evolution, and the interpretation of thermochronological data.
Assessing the work budget and efficiency of fault systems using mechanical models
Authors: Cooke Michele L. , Murphy Susan
Published: October 2004

We examine the work energy budget of actively deforming fault systems in order to develop a means of examining the systemic behavior of complex fault networks. Work done in the deformation of a faulted area consists of five components: (1) work done against gravity in uplift of topography (Wgrav); (2) internal energy of the strained host rock (Wint); (3) work done resisting friction during slip on faults (Wfric); (4) seismic energy released in earthquake events as ground shaking (Wseis); and (5) work done in initializing new faults and propagating existing faults (Wprop). The energy budget of a fault system can be expressed as WTOT = Wgrav + Wint + Wfric + Wseis + Wprop. For a balanced energy budget the total of these five components will equal the external tectonic work applied to the system. We examine the work balance within hypothetical and simulated two‐dimensional static fault systems using mechanical models. The boundary element method models produce a balanced work budget for both simple and complex fault system models. The presence of slipping faults reduces the internal strain energy of the faulted area (Wint), at a “cost” of work done against friction and gravity (and propagation and seismic energy, where applicable). Calculations of minimum work deformation match expected deformation paths, indicating the usefulness of this approach for evaluating efficiency in more complex systems. The partitioning of various work terms may express the relative efficiency or maturity of fault systems. Furthermore, calculation of potential seismic energy release can provide an upper bound to earthquake seismic moment assessments.
The temporal evolution of plate driving forces: Importance of “slab suction” versus “slab pull” during the Cenozoic
Authors: Conrad Clinton P. , Lithgow‐Bertelloni Carolina
Published: October 2004

Although mantle slabs ultimately drive plate motions, the mechanism by which they do so remains unclear. A detached slab descending through the mantle will excite mantle flow that exerts shear tractions on the base of the surface plates. This “slab suction” force drives subducting and overriding plates symmetrically toward subduction zones. Alternatively, cold, strong slabs may effectively transmit stresses to subducting surface plates, exerting a direct “slab pull” force on these plates, drawing them rapidly toward subduction zones. This motion induces mantle flow that pushes overriding plates away from subduction zones. We constrain the relative importance of slab suction and slab pull by comparing Cenozoic plate motions to model predictions that include viscous mantle flow and a proxy for slab strength. We find that slab pull from upper mantle slabs combined with slab suction from lower mantle slabs explains the observation that subducting plates currently move ∼4 times faster than nonsubducting plates. This implies that upper mantle slabs are strong enough to support their own weight. Slab suction and slab pull presently account for about 40 and 60% of the forces on plates, but slab suction only ∼30% if a low‐viscosity asthenosphere decouples plates from mantle flow. The importance slab pull has been increasing steadily through the Cenozoic because the mass and length of upper mantle slabs has been increasing. This causes subducting plates to double their speed relative to nonsubducting plates during this time period. Our model explains this temporal evolution of plate motions for the first time.
Atmospheric correction and surface spectral unit mapping using Thermal Emission Imaging System data
Authors: Bandfield Joshua L. , Rogers Deanne , Smith Michael D. , Christensen Philip R.
Published: October 2004

Three techniques are described for the extraction of surface emissivity and compositional information from Thermal Emission Imaging System (THEMIS) images. Synthetic images were constructed with different atmospheric properties and random and systematic errors to estimate the uncertainty in the retrieved surface emissivity. The three techniques are as follows: (1) A constant radiance removal algorithm determines and removes a constant radiance from atmospheric emission as well as systematic calibration radiance offsets. (2) Surface emissivity retrieval uses low‐resolution Thermal Emission Spectrometer surface emissivity data to determine atmospheric properties for an image that can be then applied to individual THEMIS pixels. (3) A spectral unit mapping algorithm determines spectral end‐member concentrations using a deconvolution routine similar to several previous applications. The initial application of these techniques to three images covering the same region of the Martian surface but at different surface temperature and atmospheric conditions yields consistent surface spectral shapes as well as end‐member concentrations. Retrieved aerosol opacity information is consistent with an independently developed opacity retrieval method. The application of the techniques described here is done in a stepwise fashion and may be applied to the desired level of analysis necessary for interpretation of surface properties.
Suprathermal ions ahead of interplanetary shocks: New observations and critical instrumentation required for future space weather monitoring
Authors: Posner A. , Schwadron N. A. , McComas D. J. , Roelof E. C. , Galvin A. B.
Published: October 2004

We report new findings on the low‐energy ion population associated with interplanetary (IP) shocks based on Wind/Suprathermal Ion Composition Spectrometer (STICS) observations. Suprathermal ions (6–200 keV) are present in the upstream region of most (86%) IP shocks at 1 AU. These foreshock ions are characterized by (1) median energy >25 keV, that is, higher than a thermal distribution; (2) spectra that increase in intensity with energy in the range 10–30 keV; (3) flow predominantly outward (antisunward). In the months surveyed, all forward shocks with speeds >30 km/s showed at least one of the above features. Because these characteristics are so often seen in foreshocks, 5 to 100 keV ions can be used to provide advance warning (∼5–72 hours) of disturbances that are drivers of the most hazardous geomagnetic storms. These characteristics of the preshock suprathermal ions could be readily monitored on future space weather missions in order to predict the arrival of the IP shocks that initiate space weather events; here we define these measurement requirements and describe the implementation of such an instrument.
Protecting the Power Grid From Electromagnetic Pulses
Authors: Simpson Sarah
Published: October 2004

A U.S. Congress‐appointed commission makes recommendations for protecting the nation's electrical power network against high‐altitude nuclear attacks and severe geomagnetic disturbances.