bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multi‐source mixing models to quantify food web sources and pathways
Authors: LUBETKIN S. C. , SIMENSTAD C. A. 
Published: September 2004

Summary

Biogeochemical tracers such as stable isotopes are often used to determine sources and pathways of organic matter through food webs, which may provide powerful indicators of environmental stress or insight into resource management issues. However, mixing models using such tracers are algebraically constrained and rarely attempted for more than two sources. This makes them of limited value for ecosystems that have numerous contributing sources.
We developed two complementary mixing models, SOURCE and STEP, which use linear programming techniques with multiple tracers, to estimate the dominant primary producer sources of consumers, and their diets and trophic levels, regardless of the number of sources and trophic steps.
SOURCE is used to estimate consumers’ direct and indirect uptake of autotrophic sources and their trophic levels. STEP calculates an estimate of a consumer's diet, which may include autotrophs and/or heterotrophs.
The two models were tested using simulated data sets of producer and consumer tracer values and then used with published δ13C, δ15N and δ34S data from a study tracing organic matter flows in a saltmarsh estuary.
SOURCE and STEP accurately estimated flows and trophic structures in the simulations, with average errors of 0·07–0·09 for SOURCE and 0·03–0·05 for STEP, depending on the number of tracers used.
We illustrate two resultant food webs for the saltmarsh estuary showing possible interpretations of the SOURCE and STEP estimates.
Synthesis and applications. SOURCE and STEP can be used with stable isotope data to estimate accurately consumers’ trophic levels, primary producer dependence and diets, even when the number of potential autotrophic sources or foods is larger than the number of tracers. SOURCE and STEP could be used to assess the roles played by individual species within food webs, to compare food webs across locations or over time, and to examine potential pollutant bioaccumulation in higher order consumers, among other potential applications. The s‐plus code for both models is available at http://staff.washington.edu/lubetkin.
Governance and Performance Implications of Diversification Strategies: Evidence from Large U.S. Firms
Authors: Singh Manohar , Mathur Ike , Gleason Kimberly C. 
Published: October 2004

AbstractRecent research focuses on explaining the diversification discount. However, there is little direct evidence regarding the relation among ownership structure, corporate governance, and corporate diversification. The results in this paper suggest that agency issues do not account for firms adopting a particular diversification strategy. Also, the performance consequences of the shift in the diversification strategy and the subsequent changes in institutional and block ownership structures are not related to agency issues. In fact, investors seem not to avoid diversified firms per se. We suggest that observed board and ownership differences between diversified and focused firms are due to their being at different stages of corporate evolution.
Stock Returns and the Business Cycle
Authors: DeStefano Michael 
Published: October 2004

AbstractThis article examines whether movements in economic factors dictated by the dividend discount model can explain broad movements in stock returns over the business cycle. As anticipated, stock returns decrease throughout economic expansions and become negative during the first half of recessions. Returns are largest during the second half of recessions, suggesting an important role for expected earnings. These results are consistent with the notion that expected stock returns vary inversely with economic conditions, yet suggest that realized returns are especially poor indicators of expected returns prior to turning points in the business cycle.
The Impact of Regulation Fair Disclosure on Information Asymmetry and Trading: An Intraday Analysis
Authors: Chiyachantana Chiraphol N. , Jiang Christine X. , Taechapiroontong Nareerat , Wood Robert A. 
Published: October 2004

AbstractThis study examines the impact of Regulation Fair Disclosure (FD) on liquidity, information asymmetry, and institutional and retail investors trading behavior. Our main findings suggest three conclusions. First, Regulation FD has been effective in improving liquidity and in decreasing the level of information asymmetry. Second, retail trading activity increases dramatically after earnings announcements but there is a significant decline in institutional trading surrounding earnings announcements, particularly in the pre‐announcement period. Last, the decline in information asymmetry around earnings announcements is closely associated with a lower participation rate in the pre‐announcement period and more active trading of retail investors after earnings releases.
A randomized study (WOS MM1) comparing the oral regime Z‐Dex (idarubicin and dexamethasone) with vincristine, adriamycin and dexamethasone as induction therapy for newly diagnosed patients with multiple myeloma
Authors: Cook G. , Clark R. E. , Morris T. C. M. , Robertson M. , Lucie N. P. , Anderson S. , Paul J. , Franklin I. M. 
Published: October 2004

SummaryWhilst infusional vincristine, adriamycin and dexamethasone (VAD) is an effective treatment for patients with multiple myeloma (MM), administration may be complicated by line‐associated infections and thromboses. The oral regime, Z‐Dex (idarubicin and dexamethasone) has been shown to be efficacious in MM. We conducted a randomized study comparing Z‐Dex with VAD as induction therapy in newly diagnosed MM patients. A total of 106 patients (median age, 56 years; range: 37–73; Durie‐Salmon stage II/III) were randomized to receive four to six cycles of Z‐Dex or VAD. Central line complications were reported in 38 patients on 57 cycles, primarily because of infection. Neutropenia (all grades) was more common in the Z‐Dex arm (P = 0·009) although grade III/IV neutropenia was not significantly different between the treatment groups (P = 0·06). Infections (all grades) were more commonly seen in the VAD arm (P = 0·001) although grade III/IV infections were not significantly different between the two groups (P = 0·081). The responses to therapy (complete/partial response) in evaluable patients were: VAD 74% vs. Z‐Dex 58%, with an estimated difference in response of 16% (95% CI −2–33, P = 0·075). VAD recipients (15%) suffered early treatment‐related mortality compared with 12% of Z‐Dex recipients. Overall, 45 patients have died: disease progression (Z‐Dex n = 13, VAD n = 10), regimen‐related toxicity (Z‐Dex n = 2, VAD n = 2), infection (Z‐Dex n = 0, VAD n = 3), other causes (Z‐Dex n = 7, VAD n = 2), unknown (Z‐Dex n = 3, VAD n = 2). This study demonstrated that Z‐Dex might be a suitable oral alternative to VAD for treating newly diagnosed MM patients, although definitive evidence for equivalence is not provided.
Treating childhood acute myeloid leukaemia with the AML‐BFM‐83 protocol: experience in a developing country
Authors: Chan L. L. , Abdel‐Latif M. E. , Ariffin W. A. , Ariffin H. , Lin H. P. 
Published: October 2004

SummaryTreatment for childhood acute myeloid leukaemia (AML) consists of remission induction chemotherapy followed by postremission chemotherapy with or without bone marrow transplantation. The AML Berlin–Frankfurt–Munster (BFM)‐83 protocol with induction–consolidation–maintenance chemotherapy for 2 years has been reported to result in a 6‐year event‐free survival (EFS) and event‐free interval (EFI) of 49% and 61% respectively. A total of 174 Malaysian children were treated with this protocol between 1985 and 1999. The 5‐year EFS and EFI was 30.7% and 48.0% respectively. The overall mortality from sepsis was 24%, which needs urgent address. The 5‐year EFS for patients treated before 1993 and after 1993 was 18.6% and 41.3%, respectively (P = 0.04), while the EFI was 32% and 60.6% respectively (P = 0.034). The improvement seen after 1993 was related to a reduction in induction deaths for that period and probably reflected increased capability and familiarity to cope with the demands of the AML‐BFM‐83 protocol and accompanying complications in the treatment of AML.
Interaction equations for multiaxial fatigue assessment of welded structures
Authors: BÄCKSTRÖM M. , MARQUIS G. 
Published: September 2004

ABSTRACTMultiaxial fatigue data from 233 welded test specimens taken from eight different studies have been evaluated based on three published interaction equations for normal and shear stress. The interaction equations were obtained from SFS 2378, Eurocode 3 and International Institute of Welding (IIW) recommendations. Fatigue classes for normal and shear stress were obtained directly from the design guidance documents. Additionally, mean fatigue strengths were determined by regression analysis of bending only and torsion only data for different specimen types. In some cases, the S–N slopes assumed by the different standards were not appropriate for the test data. Specimens that showed significantly different cracking locations or cracking mode between bending and torsion were not easily correlated by the interaction equations. Interaction equations work best in cases where both the normal stress and the shear stress tend to produce crack initiation and growth in the same location and in the same direction. The use of a damage summation of 0.5 for non‐proportional loading as recommended by IIW was consistent with experimental observations for tube‐to‐plate specimens. Other codes used a damage sum of unity.
Psychiatric medication‐induced obesity: treatment options
Authors: Schwartz T. L. , Nihalani N. , Virk S. , Jindal S. , Chilton M. 
Published: September 2004

SummaryA majority of psychiatric medications are known to generate weight gain and ultimately obesity in some patients. The authors undertook a comprehensive literature review in order to provide a better understanding of novel treatment options in regards to alleviating weight gained by use of antidepressants, antipsychotics, and mood stabilizers. There are no agents for management of this weight gain approved by the Food and Drug Administration (FDA), and existing studies on options are mainly uncontrolled, small‐scale projects with limited power to produce coherent conclusions. There is a clear need for larger studies on existing options, and future psychotropics without these side‐effects are currently in the pipeline.
Direct effects of sex steroid hormones on adipose tissues and obesity
Authors: Mayes J. S. , Watson G. H. 
Published: September 2004

SummarySex steroid hormones are involved in the metabolism, accumulation and distribution of adipose tissues. It is now known that oestrogen receptor, progesterone receptor and androgen receptor exist in adipose tissues, so their actions could be direct. Sex steroid hormones carry out their function in adipose tissues by both genomic and nongenomic mechanisms. In the genomic mechanism, the sex steroid hormone binds to its receptor and the steroid–receptor complex regulates the transcription of given genes. Leptin and lipoprotein lipase are two key proteins in adipose tissues that are regulated by transcriptional control with sex steroid hormones. In the nongenomic mechanism, the sex steroid hormone binds to its receptor in the plasma membrane, and second messengers are formed. This involves both the cAMP cascade and the phosphoinositide cascade. Activation of the cAMP cascade by sex steroid hormones would activate hormone‐sensitive lipase leading to lipolysis in adipose tissues. In the phosphoinositide cascade, diacylglycerol and inositol 1,4,5‐trisphosphate are formed as second messengers ultimately causing the activation of protein kinase C. Their activation appears to be involved in the control of preadipocyte proliferation and differentiation. In the presence of sex steroid hormones, a normal distribution of body fat exists, but with a decrease in sex steroid hormones, as occurs with ageing or gonadectomy, there is a tendency to increase central obesity, a major risk for cardiovascular disease, type 2 diabetes and certain cancers. Because sex steroid hormones regulate the amount and distribution of adipose tissues, they or adipose tissue‐specific selective receptor modulators might be used to ameliorate obesity. In fact, hormone replacement therapy in postmenopausal women and testosterone replacement therapy in older men appear to reduce the degree of central obesity. However, these therapies have numerous side effects limiting their use, and selective receptor modulators of sex steroid hormones are needed that are more specific for adipose tissues with fewer side effects.
Substrate metabolism, nutrient balance and obesity development in children and adolescents: a target for intervention?
Authors: Sun M. , Schutz Y. , Maffeis C. 
Published: September 2004

SummaryObesity results from the organism's inability to maintain energy balance over a long term. Childhood obesity and its related factors and pathological consequences tend to persist into adulthood. A cluster of factors, including high energy density in the diet (high fat intake), low energy expenditure, and disturbed substrate oxidation, favour the increase in fat mass. Oxidation of three major macronutrients and their roles in the regulation of energy balance, particularly in children and adolescents, are discussed. Total glucose oxidation is not different between obese and lean children; exogenous glucose utilization is higher whereas endogenous glucose utilization is lower in obese compared with lean children. Carbohydrate composition of the diet determines carbohydrate oxidation regardless of fat content of the diet. Both exogenous and endogenous fat oxidation are higher in obese than in lean subjects. The influence of high fat intake on accumulation of fat mass is operative rather over a long term. Several future directions are addressed, such that a combination of increased physical activity and modification in diet composition, in terms of energy density and glycemic index, is recommended for children and adolescents.
Leerstellen in Der Deutschen Gedenkkultur: Die Streitschriften Von W.G. Sebald und Klaus Briegleb
Authors: Hahn Hans‐Joachim 
Published: September 2004

AbstractDer nachstehende Aufsatz analysiert zwei breit diskutierte Veröffentlichungen von W.G. Sebald und Klaus Briegleb zum Gegenstand deutscher Erinnerungspolitik hinsichtlich des Nationalsozialismus und der Zerstörung deutscher Städte während der alliierten Bombenangriffe. Obwohl Sebald die Weise untersucht, in der die alliierten Luftangriffe in der deutschen Literatur dargestellt und nicht dargestellt wurden, während Briegleb an einigen Texten von Mitgliedern der Gruppe 47 deren Beitrag zum Verhältnis von Juden und Nichtjuden in Deutschland nach 1945 reflektiert, beschäftigen sich beide Autoren mit offensichtlichen Lücken und Leerstellen der deutschen Nachkriegskultur. Insbesondere wird dabei gezeigt, auf welche Weise beide Veröffentlichungen zur unbeendeten Debatte um das komplexe Verhältnis von deutscher Täterschaft und Opfererfahrung beitragen. Zum anderen wird eine Antwort auf die Frage versucht, warum den Texten innerhalb des deutschen Feuilletons eine beinahe antagonistische Rezeption zuteil wurde.
Border Looking: The Cold War Visuality of the Sudeten German Expellees and its Afterlife
Authors: Komska Yuliya 
Published: September 2004

AbstractAfter their expulsion from Czechoslovakia in 1945–6, the Sudeten Germans continued to revisit the (West) German‐Czech(oslovak) border, a dividing line now about to undergo institutional dissolution within the expanded European Union. Until 1987, their different groups contributed to building what became a chain of pilgrimage sites located along the Iron Curtain and visited well into the present. Closely related to the so‐called ‘Blick in die Heimat’, the environment of these borderland shrines has produced a complex visual regime that I have dubbed ‘border looking’. Within this system, as I demonstrate, the Sudeten German visuality oscillates not only between a re‐appropriating revisionist gaze and a cursory furtive, fragmented glimpse acknowledging the irrevocability of loss, but also between the ‘gaze into the homeland’ and the ‘image of the homeland’. My examination of this condition is intended to be both a contribution to a cultural history of the Cold War and a study of the expellee subjectivity. It allows us to raise questions about the effectiveness of memory inscribed on a geographical margin at a juncture when initiatives advocating a centre to commemorate the expulsion of Germans (‘Zentrum gegen Vertreibungen’) are being countered by pleas for de‐centred, regional remembrance.
Hier kannst du die Heimat, die Heimat seh’n!1
Flüchtlings‐ und Vertriebenenschicksale im Werk Arno Schmidts
Authors: Menke Timm 
Published: September 2004

AbstractAls einer der wenigen Zeitzeugen hat Arno Schmidt in seinen Werken die Thematik der Leiden der deutschen Zivilbevölkerung am Ende des Zweiten Weltkriegs aufgegriffen. Von seinem Erstlingswerk in der unmittelbaren Nachkriegszeit, der Erzählung Leviathan (publiziert 1949), bis hin zum Roman Kaff auch Mare Crisium von 1960 hat er sich immer wieder mit dem Schicksal von Vertriebenen und Flüchtlingen auseinandergesetzt. Seine Arbeiten erfahren angesichts der gegenwärtigen Aufarbeitungswelle der Thematik durch die Enkel jener Nachkriegsgeneration eine neue Aktualität und Anerkennung, die ihnen bei ihrer Erstveröffentlichung weitgehend versagt blieben. Schmidts literaturhistorisches Verdienst besteht darin, das Leiden der Vertriebenen nie isoliert zu schildern, sondern es stets in den geschichtlichen Kontext des vom deutschen Boden ausgegangenen Weltkriegs und Völkermords zu stellen.
Erinnerung, Fiktion und Geschichte. Über Die Transformation Des Erlebten Ins Kulturelle Gedächtnis: Walser – Wilkomirski – Grass
Authors: Preusser Heinz‐Peter 
Published: September 2004

AbstractIn alle Erinnerungen mischen sich konstruktive Anteile; das gilt für die schriftlich abgefassten Autobiographien in besonderem Maße. Zuweilen wird hier deutlich die Grenze zur fiktionalen Narration überschritten. Aber gerade der Fall Wilkomirski hat gezeigt, wo die ontologische Differenz gewahrt werden muss zwischen Erinnerungen als Wahrheitsaussagen und reinen Produkten künstlerischer Phantasie. Umgekehrt hat Walser diesen Anspruch gar nicht erhoben und ist dennoch für seinen Roman Ein springender Brunnen dafür haftbar gemacht worden, kein adäquates Bild der Vergangenheit geliefert und Auschwitz verschwiegen zu haben. Schließlich hat Grass mit seiner Novelle Im Krebsgang Geschichte mit den Mitteln der Fiktion ins Bewusstsein rücken wollen; das Vergessene sollte wieder Gestalt erhalten und Allgemeingut werden. Alle drei Autoren bieten Extrempunkte im Prozess der Transformation des Erlebten ins kulturelle Gedächtnis, in denen insbesondere das Verhältnis von Individuellem und Allgemeinem unterschiedlich gewichtet wird. Und sie unternehmen ihre Versuche zu einem historisch neuralgischen Zeitpunkt, in dem die Gesellschaft abzuklären sucht, wie der Holocaust, die NS‐Zeit und die Geschichte des Zweiten Weltkrieges – im Sinne eines Archivierens – erinnert werden sollen.
The Interaction of nucleotides with the tolbutamide block of cloned atp‐sensitive k+ channel currents expressed in xenopus oocytes: a reinterpretation
Authors: Gribble Fiona M. , Tucker Stephen J. , Ashcroft Frances M. 
Published: September 2004

We have examined the mechanism by which nucleotides modulate the tolbutamide block of the β‐cell ATP‐sensitive K+ channel (KATP channel), using wild‐type and mutant KATP channels heterologously expressed in Xenopus oocytes. This channel is composed of sulphonylurea receptor (SUR1) and pore‐forming (Kir6.2) subunits.
The dose–response relation for tolbutamide block of wild‐type KATP currents in the absence of nucleotide showed both a high‐affinity (Ki=2.0 μm) and a low‐affinity (Ki=1.8 mm) site.
The dose–response relation for tolbutamide block of Kir6.2ΔC36 (a truncated form of Kir6.2 which is expressed independently of SUR1) was best fitted with a single, low‐affinity site (Ki=1.7 mm). This indicates that the high‐affinity site resides on SUR1, whereas the low‐affinity site is located on Kir6.2.
ADP (100 μM) had a dual effect on wild‐type KATP currents: the nucleotide enhanced the current in the presence of Mg2+, but was inhibitory in the absence of Mg2+. Kir6.2ΔC36 currents were blocked by 100 μM ADP in the presence of Mg2+.
For wild‐type KATP currents, the blocking effect of 0.5 mm tolbutamide appeared greater in the presence of 100 μm MgADP (84 ± 2%) than in its absence (59 ± 4%). When SUR1 was mutated to abolish MgADP activation of KATP currents (K719A or K1384M), there was no difference in the extent of tolbutamide inhibition in the presence or absence of MgADP.
The ki for tolbutamide interaction with either the high‐ or low‐affinity site was unaffected by 100 μM MgADP, for both wild‐type and K719A‐K1384M currents.
MgGDP (100μM) enhanced wild‐type KATP currents and was without effect on K719A– K1384M currents. It did not affect the ki for tolbutamide block at either the high‐ or low‐affinity site.
Our results indicate that interaction of tolbutamide with the high‐affinity site (on SUR1) abolishes the stimulatory action of MgADP. This unmasks the inhibitory effect of ADP and leads to an apparent increase in channel inhibition. Under physiological conditions, abolition of MgADP activation is likely to constitute the principal mechanism by which tolbutamide inhibits the KATP channel.
Effect of hydroxylamine on photon‐like events during dark adaptation in toad rod photoreceptors
Authors: Leibrock C.S. , Lamb T.D. 
Published: September 2004

The suction pipette technique was used to investigate the recovery of toad rod photoreceptors following small bleaches of 0.2‐3% of the rhodopsin.The reduction in sensitivity and the increase in noise elicited by bleaches were measured, and from these measurements the underlying rate of occurrence of photon‐like events was calculated as a function of time after the bleach.Exposure to hydroxylamine solution was used to hasten the decomposition of the meta‐rhodopsin photoproducts. The outer segment was exposed to 110 mmhydroxylamine in a low‐Ca2+Ringer solution for a period of 10–50 s beginning 10–17 min after the bleaching exposure.By the time of the hydroxylamine exposure, the flash sensitivity and response kinetics had returned almost to normal, and were not significantly altered by the exposure.Following hydroxylamine exposure, the rate of spontaneous photon‐like events in the rods declined rapidly to near pre‐bleach levels.We conclude that hydroxylamine reduces the rate of occurrence of photon‐like events induced by a bleach, and we postulate that this reduction results from the removal of metarhodopsin (most likely metarhodopsin II) from the outer segment.Our results are consistent with a model in which photon‐like events result from reversal of the reactions (phosphorylation and capping by arrestin) that lead to inactivation of the activated form of rhodopsin, Rh*.