bluuebunny/crossref_metadata_2025_split huggingface dataset:
The transmission of electric waves around the earth's surface
Authors: Macdonald Hector Munro 
Published: December 2006

In a previous communication, an expression for the magnetic force at any point when a Hertzian oscillator is placed outside a perfectly conducting sphere was obtained, and the principal parts of this were evaluated ; in particular it was found that when the point is inside the geometrical shadow and at an angular distance from the lino of contact of the shadow with the surface which is of higher order than (
ka
)
-⅓
, the ratio of the magnetic force to the magnetic force due to the oscillator alone is a Gilbert integral; when the point and the oscillator both approach the surface this integral tends to zero, but it may be expected to give information as to the way the magnetic force dies away in tins neighbourhood where it has diminished to order (
ka
)
-½
ψ1. The magnetic force on the surface when the oscillator is also on the surface was reinvestigated by Poincaré. and he indicated that the magnetic force at angular distance θ from the oscillator is of the form A
e
-aθ
, where A and α depend on the zero of ∂/∂
z
0
{
z
0
½
K

n
+½

(
lz
0)}, for which |
n
+½-z
0
| is least. The value of this zero was calculated by Nicholson,* who also calculated the value of A. The value given by him docs not agree with the coefficient of the corresponding term in the series found below ; this may be due to the fact that the process of summation employed by him is invalid as it assumes that
z
½
K
n+½
(
lz
)/∂/∂
z
{
z
0
½
K

n
+½

(
lz
)} is a meromorphic function of
n
+½, which is not true. The problem has recently been discussed by March and Rybczynski; the discussion in the second of these papers is very interesting, but the singularity of the integrand which contributes ultimately alone to the result is one which appears to have been introduced in the process, and which is not a singularity of the original expression for which the integrand is an approximation.	The author remarks on the impossibility of representing the facts by a single exponential as the oscillator is approached ; this is fully borne out below. In what follows a aeries is obtained which represents the magnetic force at any point on the surface when the oscillator is also on the surface ; the series converges rapidly for large values of
θ
, and for largo values the first term is a sufficient approximation. For small values of
θ
the series converges very slowly. Tables showing the fall in amplitude with increase of distance have been calculated for different wave-lengths.
Differential Effects of Prenatal Exposure to Cocaine and Amphetamine on Growth Parameters and Morphometry of the Prefrontal Cortex in the Rata
Authors: TAVARES M. A. , SILVA M. C. 
Published: December 2006

SUMMARYThe purpose of this study was to investigate the differential effects of prenatal exposure to psychostimulants, e.g., cocaine or amphetamine, on basic growth parameters and morphometry of the medial prefrontal cortex of the rat. A group of pregnant Wistar rats was given 60 mg/kg body weight/day of cocaine hydrochloride and another group 10 mg/kg body weight/day of d‐amphetamine sulfate, subcutaneously, from gestational days 8 to 22. Control groups of pregnant rats were pair‐fed; litters were culled to eight pups (4 males and 4 females) weighed every other day until postnatal day 30 and every week until day 90. The body weight growth patterns modelled by a Gompertz curve were different in rats prenatally exposed to the two psychostimulants. Rats exposed to amphetamine had on average a slower growth than those exposed to cocaine, reaching an identical estimated adult weight. Allometric relationships between forebrain and body weight and cerebellum and body weight were described by two distinct postnatal growth phases that are different among the experimental groups. In the comparison of the two psychostimulants the relative cerebellum/body growth is lower in the offspring of the cocaine group than in the amphetamine group between PND14‐PND30; between PND30‐PND90 the relative growth rate is considerably higher in the offspring of the cocaine dams compared to that of the amphetamine dams. Groups of perfused animals were selected at postnatal days 14 and 30 to analyze the morphometric organization of the medial prefrontal cortex. In serial celloidin sections the volumes of the prefrontal cortex were determined; the number of neurons per unit volume of reference area was calculated using the stereological technique of the disector. The changes found in the morphometric parameters show a catch‐up at postnatal day 30 of the “increased” density of neurons of the medial prefrontal cortex found at postnatal day 14. These data show differential growth patterns of offspring from cocaine‐ and amphetamine‐exposed rats; a delayed development in the achievement of normal morphometric parameters of neurons in the prelimbic subarea of the medial prefrontal cortex occurs in the prenatally amphetamine‐exposed offspring at early ages, and a catch‐up is found after the first month of life. Complementary studies are needed to assess whether these changes have functional implications in the rats exposed prenatally to psychostimulants.
A Theory of Metric Labelled Transition Systems
Authors: VAN BREUGEL FRANCK 
Published: December 2006

ABSTRACT:Labelled transition systems are useful for giving semantics to programming languages. Kok and Rutten have developed some theory to prove semantic models defined by means of labelled transition systems equal to other semantic models. Metric labelled transition systems are labelled transition systems with the configurations and actions endowed with metrics. The additional metric structure allows us to generalize the theory developed by Kok and Rutten.
An Effective Construction of a Free z‐ultrafilter
Authors: HERRLICH HORST 
Published: December 2006

ABSTRACT:It is known that free ultrafilters cannot be constructed effectively (i.e., in ZF set theory without any additional choice principle). In this paper a nonconvergent, thus free, z‐ultrafilter is constructed effectively in a suitable zero‐dimensional topological space X. Thus the implication C‐compact ?B‐compact(which under AC is an equivalence for completely regular spaces) fails to be an equivalence in ZF even for zero‐dimensional spaces, where B‐compact (respectively, C‐compact) means that every ultrafilter (respectively, z‐ultrafilter) converges.
Topological Symmetry and the Theory of Metrization
Authors: HUNG H.H. 
Published: December 2006

ABSTRACT:We reaffirm the importance of the role of topological symmetry in the Theory of Metrization and obtain, as a consequence, a number of elegant and interesting metamorphoses of the Double Sequence Theorem of Nagata, all of which improve significantly upon some classical theorems in ways very obvious.
Completeness of the Quasi‐uniformity of Quasi‐uniform Convergence
Authors: KÜNZI HANS‐PETER A. , ROMAGUERA SALVADOR 
Published: December 2006

ABSTRACT:We discuss the completeness of the quasi‐uniformity of quasi‐uniform convergence on function spaces. In particular we observe that the notions of quasi‐uniform completeness based on the convergence of several types of stable filters provide satisfactory results in this context.
Net Spaces in Categorical Topologya
Authors: ŠLAPAL JOSEF 
Published: December 2006

ABSTRACT:In the paper we introduce the notion of S‐nets, S a nonempty construct, as a generalization of the usual nets. S‐net spaces and continuous maps between them are then defined in a natural way. For S‐net spaces we introduce a number of axioms and study the categories obtained. We find some topological and Cartesian closed categories of S‐net spaces and describe their relations to certain known topological categories.
The Krull Dimension of Alexandroff T0‐spaces
Authors: WIEDERHOLD PETRA , WILSON RICHARD G. 
Published: December 2006

ABSTRACT:Alexandroff T0‐spaces have been studied as topological models of the supports of digital images and as discrete models of continuous spaces in theoretical physics. In [17] we have defined (topologically) the Alexandroff dimension for arbitrary Alexandroff spaces. In this paper we will prove that the Alexandroff dimension of a T0‐space is equal to its Krull dimension, which is defined in terms of the lattice of closed sets of the space and which was first studied in [16]. Since the category of Alexandroff T0‐spaces is known to be isomorphic to the category of posets (see [3, Theorem 3.5]), the results could be formulated in this latter category as well.
EZE MMIRI DI EGWU, THE WATER MONARCH IS AWESOME
Authors: JELL‐BAHLSEN SABINE 
Published: December 2006

About 20 million Igbo (Ibo) live in southeastern Nigeria, a country of approximately 100 million people. Their language belongs to the Kwa‐Niger group and has several sub‐dialects. The group on which my study is based is mostly limited to the Oru‐Igbo. The Oru live in a group of hierarchically related towns along the Oguta (Ugwuta) Lake and the Njaba, Urash and other tributaries of the Niger River. They refer to themselves as riverine Igbo. Oguta is their administrative center, today, the biggest and most well‐known town. Orsu‐Obodo is their most senior town.The precolonial economy of the Oru was based primarily on farming, fishing and trading. The staples are still yam and cassava and the diet is supplemented by plantains, rice, a variety of beans, vegetables, palm oil, fish, small game, goats, sheep, poultry and cow meat. Waterways are an important means of local transportation for people, materials, produce, and trade.Oru society, like other subgroups of Igbo is patrilineal, but in precolonial times, there were parallel male and female institutions. The patri‐lineages own the land and run the towns' external and internal affairs. Today there are a number of other groups, secret societies, trade associations, Mammy Water societies, and traditional age‐grades.The Oru trace their origin to Benin, having migrated over 10 generations ago. The Obi bears the title of Eze Igwe, sometimes translated as “divine king.” However, his office is quite different from that of the Oba of Benin, the Oru being an essentially egalitarian society (Jell‐Bahlsen 1980).
Nutrition and Human Cancer
Authors: HILL MICHAEL J. 
Published: December 2006

ABSTRACT: It is now widely accepted that nutrition is as important as tobacco as a cause of human cancer. However, whereas we can dispense with tobacco with general benefit to health, we cannot do without food. It is, therefore, necessary to determine the pattern of nutrition that is associated with the lowest overall cancer risk. This is made more difficult by the fact that some kinds of cancer are associated with overnutrition (e.g., that of the colon, breast, and prostate) and some with poor nutrition (e.g., esophagus, stomach, and liver). The tools to determine this are epidemiology, animal models, in vitro studies, and dietary intervention studies. These all have their strengths and weaknesses, which will be discussed.It is concluded that the major nutrition factors associated with increased cancer risk are: (a) overweight [as a surrogate for excess energy intake]; (b) low intake of fresh fruit; (c) low intake intake of vegetables; and (d) low intake of whole‐grain cereals. There have been many other associations with cancer at specific sites noted in the literature. However, it is the overall risk of cancer that must be minimized.
Viral Theory for Ménière's Disease and Endolymphatic Hydrops: Overview and New Therapeutic Options for Viral Labyrinthitis
Authors: ARENBERG I. KAUFMAN , LEMKE CHRISTINE , SHAMBAUGH GEORGE E. 
Published: December 2006

In six cases of Ménière's disease, the sac wall was definitely fibrotic and ischemic and the epithelium either absent or markedly altered. There was partial or complete obliteration of the lumen in every case. In cases where the duct was not seen by polytomography, the epithelium was usually absent in the sac. Since none of these patients had a history of suppurative otitis media or mastoiditis, the most likely etiology for the changes observed is an old viral labyrinthitis affecting especially or perhaps primarily the duct and sac, destroying or markedly impairing the normal resorption of endolymph.—George E. Shambaugh and I. Kaufman Arenberg
Tenascin-C Stimulates Glioma Cell Invasion through Matrix Metalloproteinase-12
Authors: Sarkar Susobhan , Nuttall Robert K. , Liu Shuhong , Edwards Dylan R. , Yong V. Wee 
Published: December 2006

Abstract
The capacity of glioma cells to invade extensively within the central nervous system is a major cause of the high morbidity rate of primary malignant brain tumors. Glioma cell invasion involves the attachment of tumor cells to extracellular matrix (ECM), degradation of ECM components, and subsequent penetration into adjacent brain structures. These processes are accomplished in part by matrix metalloproteinases (MMP) within a three-dimensional milieu of the brain parenchyma. As the majority of studies have used a two-dimensional monolayer culture system, we have used a three-dimensional matrix of collagen type I gel to address glioma-secreted proteases, ECM, and invasiveness of glioma cells. We show that in a three-dimensional collagen type I matrix, the presence of tenascin-C, commonly elevated in high-grade gliomas, increased the invasiveness of glioma cells. The tenascin-C–mediated invasiveness was blocked by metalloproteinase inhibitors, but this did not involve the gelatinases (MMP-2 and MMP-9) commonly implicated in two-dimensional glioma growth. A thorough analysis of 21 MMPs and six members of a disintegrin and metalloproteinase domain showed that MMP-12 was increased in gliomas by tenascin-C in three-dimensional matrix. Furthermore, examinations of resected specimens revealed high MMP-12 levels in the high-grade glioblastoma multiforme tumors. Finally, a function-blocking antibody as well as small interfering RNA to MMP-12 attenuated the tenascin-C–stimulated glioma invasion. These results identify a new factor, MMP-12, in regulating glioma invasiveness through interaction with tenascin-C. (Cancer Res 2006; 66(24): 11771-80)
Cross-talk between Peroxisome Proliferator-Activated Receptor δ and Cytosolic Phospholipase A2α/Cyclooxygenase-2/Prostaglandin E2 Signaling Pathways in Human Hepatocellular Carcinoma Cells
Authors: Xu Lihong , Han Chang , Lim Kyu , Wu Tong 
Published: December 2006

Abstract
Peroxisome proliferator-activated receptor δ (PPARδ) is a nuclear transcription factor that is recently implicated in tumorigenesis besides lipid metabolism. This study describes the cross-talk between the PPARδ and prostaglandin (PG) signaling pathways that coordinately regulate human hepatocellular carcinoma (HCC) cell growth. Activation of PPARδ by its pharmacologic ligand, GW501516, enhanced the growth of three human HCC cell lines (HuH7, HepG2, and Hep3B), whereas inhibition of PPARδ by small interfering RNA prevented growth. PPARδ activation up-regulates the expression of cyclooxygenase (COX)-2, a rate-limiting enzyme for PG synthesis, and tumor growth. PPARδ activation or PGE2 treatment also induced the phosphorylation of cytosolic phospholipase A2α (cPLA2α), a key enzyme that releases arachidonic acid substrate for PG production via COX. Activation of cPLA2α by the calcium ionophore A23187 enhanced PPARδ binding to PPARδ response element (DRE) and increased PPARδ reporter activity, which was blocked by the selective cPLA2α inhibitors. Consistent with this, addition of arachidonic acid to isolated nuclear extracts enhanced the binding of PPARδ to DRE in vitro, suggesting a direct role of arachidonic acid for PPARδ activation in the nucleus. Thus, PPARδ induces COX-2 expression and the COX-2–derived PGE2 further activates PPARδ via cPLA2α. Such an interaction forms a novel feed-forward growth-promoting signaling that may play a role in hepatocarcinogenesis. (Cancer Res 2006; 66(24): 11859-68)
A Ras Inhibitor Tilts the Balance between Rac and Rho and Blocks Phosphatidylinositol 3-Kinase–Dependent Glioblastoma Cell Migration
Authors: Goldberg Liat , Kloog Yoel 
Published: December 2006

Abstract
Glioblastoma multiforme are highly aggressive tumors for which no adequate treatment has yet been developed. Glioblastoma multiforme show large amounts of active Ras, considered an appropriate target for directed therapy. Here, we show that the Ras inhibitor S-trans, trans-farnesyl thiosalicylic acid (FTS) can avert the transformation of human glioblastoma multiforme cells by inhibiting both their migration and their anchorage-independent proliferation. FTS, by down-regulating Ras activity in glioblastoma multiforme cells, inhibited phosphatidylinositol 3-kinase signaling, resulting in decreased activity of Rac-1. At the same time, activation of RhoA was increased. These two small GTPases are known to control the arrangement of the actin cytoskeleton. By tilting the balance between Rac-1 and RhoA activities, FTS caused the glioblastoma multiforme cells to undergo profound changes in morphology, including rearrangement of actin into stress fibers and assembly of focal adhesions, both of which are governed by RhoA signaling. These morphologic changes allowed strong attachment of the cells to the matrix, rendering them immobile. The results show that FTS should be considered as a candidate drug for glioblastoma multiforme therapy because it targets not only cell proliferation but also cell migration and invasion, which together constitute the most problematic aspect of these malignancies. (Cancer Res 2006; 66(24): 11709-17)
N-Glycosylation of MDA-7/IL-24 Is Dispensable for Tumor Cell–Specific Apoptosis and “Bystander” Antitumor Activity
Authors: Sauane Moira , Gupta Pankaj , Lebedeva Irina V. , Su Zao-zhong , Sarkar Devanand , Randolph Aaron , Valerie Kristoffer , Gopalkrishnan Rahul V. , Fisher Paul B. 
Published: December 2006

Abstract
Biochemical and genetic mutation–based analyses confirm that the MDA-7/IL-24 protein can induce transformed cell–specific apoptosis through a mechanism involving endoplasmic reticulum (ER) stress–associated pathways. Covalent modifications by N-linked glycans in the ER contribute to the conformational maturation and biological functions of many proteins. Because MDA-7/IL-24 is a glycosylated protein, we investigated the role of glycosylation in mediating the specific biological and “bystander” antitumor activities of this cytokine. An adenovirus vector expressing a nonsecreted and nonglycosylated version of MDA-7/IL-24 protein was generated via deletion of its signal peptide and point mutations of its three N-glycosylated sites. In this study, we showed that this intracellular nonglycosylated protein was as effective as wild-type MDA-7/IL-24 protein in inducing apoptosis in multiple tumor cell lines. Both constructs (a) displayed transformed cell specificity and localization to the ER compartment, (b) mediated apoptosis through JAK/STAT-independent and p38MAPK-dependent pathways, (c) induced sustained ER stress as evidenced by expression of ER stress markers (BiP/GRP78, GRP94, XBP-1, and eIF2α), and (d) generated proteins that physically interacted with BiP/GRP78. Additionally, an expression construct containing the mda-7/IL-24 signal peptide linked to the mutated nonglycosylated mda-7/IL-24 gene retained the ability to induce bystander antitumor activity. These studies reveal that MDA-7/IL-24 glycosylation is not mandatory for inducing cell death or bystander activities in different cancer cells, providing new insights into the mechanism by which MDA-7/IL-24 induces apoptosis and ER stress. (Cancer Res 2006; 66(24): 11869-77)
Dendrimer-Encapsulated Camptothecins: Increased Solubility, Cellular Uptake, and Cellular Retention Affords Enhanced Anticancer Activity In vitro
Authors: Morgan Meredith T. , Nakanishi Yuka , Kroll David J. , Griset Aaron P. , Carnahan Michael A. , Wathier Michel , Oberlies Nicholas H. , Manikumar Govindarajan , Wani Mansukh C. , Grinstaff Mark W. 
Published: December 2006

Abstract
A biocompatible polyester dendrimer composed of the natural metabolites, glycerol and succinic acid, is described for the encapsulation of the antitumor camptothecins, 10-hydroxycamptothecin and 7-butyl-10-aminocamptothecin. The cytotoxicity of the dendrimer-drug complex toward four different human cancer cell lines [human breast adenocarcinoma (MCF-7), colorectal adenocarcinoma (HT-29), non–small cell lung carcinoma (NCI-H460), and glioblastoma (SF-268)] is also reported, and low nmol/L IC50 values are measured. Cellular uptake and efflux measurements in MCF-7 cells show an increase of 16-fold for cellular uptake and an increase in drug retention within the cell when using the dendrimer vehicle. (Cancer Res 2006; 66(24): 11913-21)
A Novel Pathway Involving Melanoma Differentiation Associated Gene-7/Interleukin-24 Mediates Nonsteroidal Anti-inflammatory Drug–Induced Apoptosis and Growth Arrest of Cancer Cells
Authors: Zerbini Luiz F. , Czibere Akos , Wang Yihong , Correa Ricardo G. , Otu Hasan , Joseph Marie , Takayasu Yuko , Silver Moriah , Gu Xuesong , Ruchusatsawat Kriangsak , Li Linglin , Sarkar Devanand , Zhou Jin-Rong , Fisher Paul B. , Libermann Towia A. 
Published: December 2006

AbstractNumerous studies show that nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in chemoprevention or treatment of cancer. Nevertheless, the mechanisms underlying these antineoplastic effects remain poorly understood. Here, we report that induction of the cancer-specific proapoptotic cytokine melanoma differentiation associated gene-7/interleukin-24 (MDA-7/IL-24) by several NSAIDs is an essential step for induction of apoptosis and G2-M growth arrest in cancer cells in vitro and inhibition of tumor growth in vivo. We also show that MDA-7/IL-24–dependent up-regulation of growth arrest and DNA damage inducible 45 α (GADD45α) and GADD45γ gene expression is sufficient for cancer cell apoptosis via c-Jun NH2-terminal kinase (JNK) activation and growth arrest induction through inhibition of Cdc2-cyclin B checkpoint kinase. Knockdown of GADD45α and GADD45γ transcription by small interfering RNA abrogates apoptosis and growth arrest induction by the NSAID treatment, blocks JNK activation, and restores Cdc2-cyclin B kinase activity. Our results establish MDA-7/IL-24 and GADD45α and GADD45γ as critical mediators of apoptosis and growth arrest in response to NSAIDs in cancer cells. (Cancer Res 2006; 66(24): 11922-31)