bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of energy‐space diagrams in free‐electron models of field electron emission
Authors: Forbes Richard G. 
Published: June 2004

AbstractAn improved method is reported for deriving the equations for cold field electron emission from a free‐electron metal. It is shown that the derivation of these equations can be presented as a straightforward double integral in a space where the vertical axis represents the total electron energy, and the horizontal axis represents the component of electron kinetic energy parallel to the emitter surface. A general approach is developed that applies to a tunnelling barrier of any shape. It is shown that the temperature‐correction factor derived by Murphy and Good for emission through an image‐rounded barrier also applies to a more general barrier. For the standard image‐rounded barrier the results coincide with those of Murphy and Good, but the derivation is more straightforward mathematically and the physics involved can be visualized more easily. The method developed here should be a good foundation for developing an improved theory of cold field electron emission from semiconductors: the main object of the paper is to lay this foundation. Copyright © 2004 John Wiley & Sons, Ltd.
Characterization of the effectiveness of hexose transporters for transporting xylose during glucose and xylose co‐fermentation by a recombinant Saccharomyces yeast
Authors: Sedlak Miroslav , Ho Nancy W. Y. 
Published: June 2004

AbstractWe have developed recombinant Saccharomyces yeasts that can effectively co‐ferment glucose and xylose to ethanol. However, these yeasts still ferment glucose more efficiently than xylose. The transport of xylose could be one of the steps limiting the fermentation of xylose. In this study, we characterized the changes in the expression pattern of the hexose transporter and related genes during co‐fermentation of glucose and xylose using one of our recombinant yeasts, Saccharomyces cerevisiae 424A(LNH‐ST). The transcription of the hexose transporter and related genes was strongly influenced by the presence of glucose; HXT1, HXT2 and HXT3 were greatly activated by glucose and HXT5, HXT7 and AGT1 were significantly repressed by glucose. We also examined the effectiveness of individual transporters encoded by HXT1, HXT2, HXT4, HXT5, HXT7 and GAL2 genes for transporting xylose during co‐fermentation of glucose and xylose in a Saccharomyces hxt° mutant (RE700A). We compared these hxt° derivatives to RE700A wild‐type strain (S. cerevisiae MC996A) where all of them contained the same xylose metabolizing genes present in our xylose‐fermenting yeasts such as 424A(LNH‐ST). Our results showed that recombinant RE700A containing the cloned HXT7 or HXT5 were substantially more effective for fermenting xylose to ethanol. In addition, we found that the efficiency of transporters for intracellular accumulation of xylose was as follows: HXT7 > HXT5 > GAL2 > WT > HXT1 > HXT4 > > > RE700A. Furthermore, we provided evidence that the Saccharomyces galactose transporter system could be a highly effective xylose transporter. The information reported here should be of great importance for improving the Saccharomyces yeast transport of xylose. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of a Ty1‐less variant of Saccharomyces paradoxus: the gain and loss of Ty1 elements
Authors: Moore Sharon P. , Liti Gianni , Stefanisko Karen M. , Nyswaner Katherine M. , Chang Caroline , Louis Edward J. , Garfinkel David J. 
Published: June 2004

AbstractBecause Ty elements transpose through an RNA intermediate, element accumulation through retrotransposition must be regulated or offset by element loss to avoid uncontrolled genome expansion. Here we examine the fate of Ty sequences in Saccharomyces strain 337, a strain that is reported to lack Ty1 and Ty2 elements, but contains remnant solo long terminal repeats (LTRs). Although strain 337 was initially classified as Saccharomyces cerevisiae, our work indicates that this strain is more closely related to S. paradoxus. Several degenerate Ty1 and Ty2 LTRs were mapped to the same insertion sites as full‐length Ty1 and Ty2 elements in S. cerevisiae, suggesting that this strain lost Ty elements by LTR–LTR recombination. Southern analysis indicates that strain 337 also lacks Ty4 and Ty5 elements. We estimated the rates of element gain and loss in this strain by introducing a single transposition‐competent Ty1 element. The results indicate that Ty1 retrotransposition occurs at a much higher rate than elimination, suggesting that copy‐number‐dependent co‐factors or environmental conditions contribute to the loss of Ty elements in this genome. Copyright © 2004 John Wiley & Sons, Ltd.
Comparative Effectiveness of Several Agents for Preventing Postoperative Adhesions
Authors: Kutlay Jehat , Ozer Yusuf , Isık Burak , Kargici Hulagu 
Published: June 2004

AbstractPostoperative adhesions (PAs) are usually clinically asymptomatic. Symptomatic cases, however, may present with chronic abdominal and pelvic pain, infertility, and intestinal obstruction; and they may require intensive, costly therapeutic modalities. Various agents have been used to prevent PAs, but the results indicate general suboptimal effectiveness. Our objective was to evaluate the comparative effectiveness of two pharmacologic agents for preventing PA: nadroparine calcium (low‐molecular‐weight heparin, or LMWH) and aprotinin, as well as a barrier agent, sodium hyaluronate/carboxymethycellulose (SCMC). Our subjects were 40 male Wistar‐Albino rats divided into four groups, each consisting of 10 rats, which underwent standard cecal abrasion preceding midline laparotomy. In the control group (group 1) 1 ml of 0.9% NaCl was administered intraperitoneally before abdominal closure. In the three preventive groups, 100 U AXa (anti factor X activity) LMWH, 1800 IU aprotinin, and SCMC were administered intraperitoneally to groups 2, 3, and 4, respectively. Relaparotomy was performed on the 14th postoperative day. Visceral and abdominal wall adhesions were scored in a blinded fashion. The adhesion scores (mean ± SD) for groups 1, 2, 3, and 4 were 2.00 ± 0.67, 0.6.00 ± 0.84, 1.10 ± 0.74, and 0.20 ± 0.42, respectively. The differences in the adhesion scores among all three preventive groups (groups 2, 3, 4) were statistically significant when compared with the control group (p < 0.001, p = 0.017, p < 0.001, respectively). Intraperitoneal SCMC and administration of LMWH were more effective than giving aprotinin.
Molecular Detection of APC, K‐ras, and p53 Mutations in the Serum of Colorectal Cancer Patients as Circulating Biomarkers
Authors: Wang Jaw‐Yuan , Hsieh Jan‐Sing , Chang Mei‐Yin , Huang Tsung‐Jen , Chen Fang‐Ming , Cheng Tian‐Lu , Alexandersen Ketil , Huang Yu‐Sheng , Tzou Wen‐Shyong , Lin Shiu‐Ru 
Published: June 2004

AbstractEarly detection of tumor DNA in serum/plasma prior to the development of recurrence or metastases could help improve the outcome of patients with colorectal cancer (CRC) after tumor resection. Recent advances in the detection of tumor DNA in the serum/plasma has opened up numerous new areas for investigation and new possibilities for molecular diagnosis. APC and K‐ras mutations are considered to be early‐stage developments of CRCs, whereas p53 mutations are thought to be relatively late events in the tumorigenesis of CRCs. The aim of this study was to search for the presence of genetic mutations in the DNA extracted from the serum of CRC patients and healthy subjects. We simultaneously evaluate the significance of APC, K‐ras, and p53 gene mutations in cancer tissues and their paired serum samples of 104 CRC patients by polymerase chain reaction‐single strand conformation polymorphism analysis (PCR‐SSCP) followed by direct sequencing. Additionally, analysis was carried out to detect the serum carcinoembryonic antigen (CEA) levels in CRC patients. Overall, we found at least one of the gene mutations in tumor tissues from 75% (78/104) of the CRC patients. Comparison of the three molecular markers showed that the detection rates in the serum were 30.4%, 34.0%, and 34.2% for APC, K‐ras, and p53 genes, respectively. Of these patients, 46.2% (36/78) were identified as having positive serum results, whereas all healthy controls remained negative. The overall positive tumor DNA detection rates in the serum were 0% (0/7) for Dukes’ A classification, 22.4% (11/49) for Dukes’ B, 48.7% (19/39) for Dukes’ C, and 66.7% (6/9) for Dukes’ D. The detection rate increased as the tumor stage progressed (p = 0.012). Concurrently, a significant difference was observed between lymph node metastases and positive serum tumor DNA detection (p < 0.001). A significantly higher postoperative metastasis/recurrence rate in patients harboring gene mutations with serum tumor DNA than those without serum tumor DNA was also demonstrated (p < 0.001). However, no significant correlation between the postoperative metastasis/recurrence and serum CEA levels was observed (p = 0.247). These data suggest that the identification of circulating tumor DNA using the molecular detection of APC, K‐ras, and p53 gene mutations is a potential tool for early detection of postoperative recurrence/metastases. Moreover, these genes may be potential molecular markers of poor clinical outcome in CRC patients.
Source Control for Surgical Infections
Authors: Schein Moshe , Marshall John 
Published: June 2004

AbstractThe concept of source control encompasses all of the physical interventions, surgical and otherwise, that are used to treat infection. Although source control is one of the most important aspects of the treatment of serious infection, it has received relatively little attention. It is the topic of this overview, which draws heavily on a book we edited recently: Source Control: A Guide to the Management of Surgical Infection (Springer‐Verlag, 2002). The first section focuses on general considerations: historical perspective, scientific basis, and surgical principles of source control. The second section highlights specific considerations of source control in various situations.
Collagen fibres of the spontaneously ruptured human tendons display decreased thickness and crimp angle
Authors: Järvinen Tero A. H. , Järvinen Teppo L. N. , Kannus Pekka , Józsa László , Järvinen Markku 
Published: June 2004

AbstractPurpose. To study collagen fibre thickness and crimp formation in healthy and ruptured human tendons.Methods. The thickness, crimp angle and wavelength of the collagen fibres were analyzed by interference and polarization microscopy and the samples were studied by transmission and scanning electron microscopy in four different healthy human tendons (Achilles, Quadriceps, Biceps brachii and Extensor pollicis longus) and in 66 spontaneously ruptured tendons.Results. In the normal (healthy) tendons, the diameter and crimp angle of the collagen fibres varied greatly between the four different tendons, the thickest fibres with the largest crimp angle being in the Achilles and Quadriceps tendons, whereas the Biceps brachii and Extensor pollicis longus, tendons that bear lighter strains but carry functions of high specificity, were found to have substantially smaller collagen fibres with lower crimp angle. Ruptured tendons had significantly smaller collagen fibre diameter than the normal tendons, the fibre diameter being −36% in comparison to their healthy counterparts in the Achilles tendons (P < 0.0001), −24% in the Quadriceps tendons (P < 0.0001), −37% in the Biceps brachii (P < 0.0001) and −14% in the Extensor pollicis longus (P = 0.10), respectively. Similarly, the crimp angle of the collagen fibres was also found to be lower in the ruptured tendons than in healthy, normal tendons. Further, the collagen fibres in the ruptured human tendons showed great variation in the crimp angle between the adjacent fibres and in the successive crimps of the same fibre.Conclusion. Our results show that spontaneously ruptured tendons display focal regions with decreased collagen fibre thickness, decreased crimp angle and disrupted crimp continuity, microscopic alterations that possibly result in reduced strength of the tendons being less resistant to tensile forces, and thus, place them at increased risk of ruptures. © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.
The Deligne complex for the four-strand braid group
Authors: Charney Ruth 
Published: June 2004

This paper concerns the homotopy type of hyperplane arrangements associated to infinite Coxeter groups acting as reflection groups on

C

n

\mathbb C^n

. A long-standing conjecture states that the complement of such an arrangement should be aspherical. Some partial results on this conjecture were previously obtained by the author and M. Davis. In this paper, we extend those results to another class of Coxeter groups. The key technical result is that the spherical Deligne complex for the 4-strand braid group is CAT(1).
Dual Radon transforms on affine Grassmann manifolds
Authors: Gonzalez Fulton , Kakehi Tomoyuki 
Published: June 2004

Fix

0
≤
p
>
q
≤
n
−
1

0 \leq p > q \leq n-1

, and let

G
(
p
,
n
)

G(p,n)

and

G
(
q
,
n
)

G(q,n)

denote the affine Grassmann manifolds of

p
p

- and

q
q

-planes in

R

n

\mathbb {R}^n

. We investigate the Radon transform

R

(
q
,
p
)

:

C

∞

(
G
(
q
,
n
)
)
→

C

∞

(
G
(
p
,
n
)
)

\mathcal {R}^{(q,p)} : C^{\infty } (G(q,n)) \to C^{\infty } (G(p,n))

associated with the inclusion incidence relation. For the generic case

dim
⁡
G
(
q
,
n
)
>
dim
⁡
G
(
p
,
n
)

\dim G(q,n) > \dim G(p,n)

and

p
+
q
>
n

p+q > n

, we will show that the range of this transform is given by smooth functions on

G
(
p
,
n
)

G(p,n)

annihilated by a system of Pfaffian type differential operators. We also study aspects of the exceptional case

p
+
q
=
n

p+q =n

.
Varieties of tori and Cartan subalgebras of restricted Lie algebras
Authors: Farnsteiner Rolf 
Published: June 2004

This paper investigates varieties of tori and Cartan subalgebras of a finite-dimensional restricted Lie algebra

(

g

,
[
p
]
)

(\mathfrak {g},[p])

, defined over an algebraically closed field

k
k

of positive characteristic

p
p

. We begin by showing that schemes of tori may be used as a tool to retrieve results by A. Premet on regular Cartan subalgebras. Moreover, they give rise to principal fibre bundles, whose structure groups coincide with the Weyl groups in case

g

=
Lie
⁡
(

G

)

\mathfrak {g}= \operatorname {Lie}(\mathcal {G})

is the Lie algebra of a smooth group

G

\mathcal {G}

. For solvable Lie algebras, varieties of tori are full affine spaces, while simple Lie algebras of classical or Cartan type cannot have varieties of this type. In the final sections the quasi-projective variety of Cartan subalgebras of minimal dimension

rk

(

g

)

\textrm {rk}(\mathfrak {g})

is shown to be irreducible of dimension

dim
k

⁡

g

−

rk

(

g

)

\dim _k\mathfrak {g}-\textrm {rk}(\mathfrak {g})

, with Premet’s regular Cartan subalgebras belonging to the regular locus.
Free trade and garment work: the impact of NAFTA on service and manufacturing jobs in the Los Angeles apparel industry
Authors: Kessler Judi A. 
Published: June 2004

This article examines the impact of North American economic integration on apparel‐related employment in Los Angeles and provides a first look at consequent changes in the composite of apparel‐related occupations in the Los Angeles apparel industry. It assesses the effects of new NAFTA‐generated transnational production networks and global production strategies on apparel industry employment, including the creation of ‘new NAFTA jobs’in the greater Los Angeles area, as well as changes in hiring patterns across occupational categories. The article also explores the accessibility of NAFTA‐generated apparel jobs to displaced workers in the labor‐intensive segments of the industry. The findings suggest that the new NAFTA jobs are inaccessible to the thousands of apparel manufacturing workers displaced by the trend in offshore sourcing. Finally, the article discusses the implications and consequences of recent state‐industry partnership programs designed to train and cross‐train sewing operators for jobs that are rapidly leaving the region.Cet article examine l'impact de l'intégration économique nord‐américaine sur l'emploi dans l'habillement à Los Angeles, en procurant un premier regard sur les changements occasionnés pour la mosaïque des métiers de ce secteur d'activités dans cette ville. Il évalue les effets des nouveaux réseaux de fabrication transnationale générés par l'ALENA et des stratégies de production mondialisées sur l'emploi du secteur, y compris la création des ‘nouveaux emplois ALENA’ dans l'agglomération de Los Angeles, ainsi que les changements dans les schémas d'embauche pour les diverses catégories professionnelles. De plus, il explore l'accessibilité des emplois de l'habillement créés par l'ALENA pour les travailleurs déplacés dans les segments industriels à forte main‐d'œuvre. D'après les résultats, ces nouveaux emplois sont inaccessibles aux milliers d'ouvriers de la fabrication vestimentaire déplacés par la tendance à un approvisionnement étranger. Enfin, sont abordées les implications et conséquences des récents programmes de partenariat État‐industrie pour la formation et la formation polyvalente d'opératrices de machines à coudre à des postes qui quittent rapidement la région.
Community economic development in a context of globalization and metropolization: a comparison of four North American cities
Authors: Morin Richard , Hanley Jill 
Published: June 2004

In this article, we highlight the links, few as they are, between metropolitan development institutions and community economic development (CED) organizations in a context of global economy where urban agglomerations compete for investments, while some groups of people are marginalized and some neighbourhoods are declining. First, we begin with a theoretical consideration of globalization, metropolization and community economic development. Second, we examine the relation between institutions responsible for metropolitan development and CED organizations in two Canadian agglomerations, Toronto and Montreal, and two American ones, Boston and Pittsburgh. Third, we suggest some explanations for the weak linkages between CED organizations and metropolitan institutions by raising questions about the identity, the resources and the political aspect of CED organizations, and about the vision of metropolitan actors.L'article met en avant les liens, aussi rares soient‐ils, entre institutions d'aménagement métropolitain et organisations de développement économique communautaire (DEC) dans le contexte d'une économie mondialisée où les agglomérations urbaines rivalisent dans leur quête d'investissements, tandis que certains groupes sont marginalisés et des quartiers déclinent. Ce travail commence par une étude théorique de la mondialisation, de la métropolisation et du développement économique communautaire. Il examine ensuite la relation entre institutions chargées de l'aménagement métropolitain et organisations de DEC dans deux agglomérations canadiennes, Toronto et Montréal, et américaines, Boston et Pittsburgh. Enfin, il tente d'expliquer les liens ténus entre les deux types d'organismes au travers de plusieurs questions sur l'identité, les ressources et l'aspect politique des organisations de CED, ainsi que sur la vision des acteurs métropolitains.
World city formation, geopolitics and local political process: Taipei's ambiguous development
Authors: Wang Jenn‐hwan 
Published: June 2004

This article argues that the existing literature on world city formation overlooks geopolitics and political struggles in accounting for a city's transformation. Using Taipei as a case study, the article shows that geo‐economics, geopolitics and local politics each played an important role in Taipei's ambiguous world city formation in the late 1990s and are expected to continue to do so in the not too promising future. It is argued that the globalization process in the 1980s and the corresponding restructuring of the Taiwan economy induced the state to adopt a new developmental strategy that enhanced Taipei's competitiveness. However, the democratization process facilitated a new nation‐building process in the late‐1990s and the newly‐elected regime suppressed the city of Taipei's ongoing development, as a consequence of which Taipei's competitiveness as a regional world city has been declining. Geopolitics and local politics are thus found to explain to a large degree the ambiguities currently defining Taipei's world city formation.La littérature existante sur la formation des villes mondiales néglige les luttes géopolitiques et politiques dans ses explications de la transformation d'une ville. Prenant comme cas Taipei, l'article montre que géo‐économie, géopolitique et politique locale ont chacune joué un r^le important dans la formation complexe de cette ville mondiale vers la fin des années 1990, rôle qu'elles devraient conserver dans un avenir peu prometteur. Le processus de mondialisation des années 1980 et la restructuration subséquente de l'économie taiwanaise ont conduit l'&#5´tat à adopter une nouvelle stratégie de développement, laquelle a renforcé la compétitivité de Taipei. En revanche, le processus de démocratisation a encouragé un processus de construction nationale dans la fin des années 1990 et le régime récemment élu a asphyxié l'évolution de cette ville, en conséquence de quoi la compétitivité de Taipei en tant que ville mondiale de la région a décliné. La géopolitique et la politique locale peuvent donc expliquer en grande partie les ambiguïtés qui définissent actuellement la formation de la ville mondiale de Taipei.