bluuebunny/crossref_metadata_2025 huggingface dataset:
Repulsion and Attraction of Axons by Semaphorin3D Are Mediated by Different NeuropilinsIn Vivo
Authors: Wolman Marc A. , Liu Yan , Tawarayama Hiroshi , Shoji Wataru , Halloran Mary C.
Published: September 2004

Class 3 semaphorins are known to repel and/or sometimes attract axons; however, their role in guiding developing axons in the CNSin vivois still essentially unknown. We investigated the role of Semaphorin3D (Sema3D) in the formation of the early axon pathways in the zebrafish CNS. Morpholino knock-down shows that Sema3D is essential for the correct formation of two early axon pathways. Sema3D appears to guide axons of the nucleus of the medial longitudinal fasciculus (nucMLF) by repulsion and modulation of fasciculation. In contrast, Sema3D appears to be attractive to telencephalic neurons that form the anterior commissure (AC). Knock-down of Neuropilin-1A (Npn-1A) phenocopied the effects of Sema3D knock-down on the nucMLF axons, and knock-down of either Npn-1A or Npn-2B phenocopied the defects of the AC. Furthermore, simultaneous partial knock-down experiments demonstrated genetic interactions among Sema3D, Npn-1A, and Npn-2B. Together, these data support the hypothesis that Sema3D may act as a repellent through receptors containing Npn-1A and as an attractant via receptors containing Npn-1A and Npn-2B.
ATP-Induced Non-Neuronal Cell Permeabilization in the Rat Inner Retina
Authors: Innocenti Barbara , Pfeiffer Sylke , Zrenner Eberhart , Kohler Konrad , Guenther Elke
Published: September 2004

The P2X7subtype holds a special position among P2X receptors because of its ability to act both as a classical, ligand-gated ion channel, and as a permeabilization pore that can induce cell death under prolonged activation by ATP.

We have shown previously that, in rat retina, P2X7receptors are located in the inner nuclear layer and ganglion cell layer (GCL). The present study was aimed at finding whether retinal P2X7receptors can act as a mediator of cell permeabilization and, if so, at identifying the cellular target(s) of this effect.

As an indicator of cell permeabilization, we used the fluorescent dye YO-PRO-1 (molecular weight, 375 Da), which enters cells only through large pores like those opened by prolonged or sustained stimulation of P2X7receptors and binds to DNA, providing a stable labeling of the activated cells.

Different agonists for P2 receptors were tested for their ability to cause cell permeabilization in flat-mounted rat retinas. Among them, only high concentrations of ATP (500 μM) and BzATP (2′,3′-O-(4-benzoyl-benzoyl)-ATP triethylammonium) (100 μM) were able to induce accumulation of YO-PRO-1 in the GCL and in the nerve fiber layer, suggesting that different cell types were responding to P2X7stimulation. This effect was blocked by the P2 antagonists suramin and PPADS (pyridoxal-phosphate-6-azophenyl-2′,4′-disulfonic acid) and by the P2X7-selective inhibitor Brilliant Blue G.

To identify the retinal cell types affected by ATP-induced permeabilization, we usedin vivolabeling techniques. Our data clearly reveal that prolonged stimulation of P2X7receptors elicits permeabilization exclusively in microglial cells but not in neurons of the inner retina.
Patterns of Gene Expression Reveal a Temporally Orchestrated Wound Healing Response in the Injured Spinal Cord
Authors: Velardo Margaret J. , Burger Corinna , Williams Philip R. , Baker Henry V. , López M. Cecilia , Mareci Thomas H. , White Todd E. , Muzyczka Nicholas , Reier Paul J.
Published: September 2004

Spinal cord injury (SCI) induces a progressive pathophysiology affecting cell survival and neurological integrity via complex and evolving molecular cascades whose interrelationships are not fully understood. The present experiments were designed to: (1) determine potential functional interactions within transcriptional expression profiles obtained after a clinically relevant SCI and (2) test the consistency of transcript expression after SCI in two genetically and immunologically diverse rat strains characterized by differences in T cell competence and associated inflammatory responses. By interrogating Affymetrix U34A rat genome GeneChip microarrays, we defined the transcriptional expression patterns in midcervical contusion lesion sites between 1 and 90 d postinjury of athymic nude (AN) and Sprague Dawley (SD) strains. Stringent statistical analyses detected significant changes in 3638 probe sets, with 80 genes differing between the AN and SD groups. Subsequent detailed functional categorization of these transcripts unveiled an overall tissue remodeling response that was common to both strains. The functionally organized gene profiles were temporally distinct and correlated with repair indices observed microscopically and by magnetic resonance microimaging. Our molecular and anatomical observations have identified a novel, longitudinal perspective of the post-SCI response, namely, that of a highly orchestrated tissue repair and remodeling repertoire with a prominent cutaneous wound healing signature that is conserved between two widely differing rat strains. These results have significant bearing on the continuing development of cellular and pharmacological therapeutics directed at tissue rescue and neuronal regeneration in the injured spinal cord.
Organizational Commitment and Constraints on Work-Family Policy Use: Corporate Flexibility Policies in a Global Firm
Authors: Blair-Loy Mary , Wharton Amy S.
Published: September 2004

Academics, policy makers, and human resource professionals advocate flexibility policies as a way to help employees balance work and family and to promote a more committed workforce for employers. This mutually beneficial scenario assumes that employees are interested in work-family policies and perceive themselves as being able to use them. We examine these issues among managers and professionals in a global, high-commitment firm. Our analysis of individual-level and work group–level factors that contribute to workers' feeling constrained from using a corporation's generous official flexibility policies reveals that those with the heaviest job demands and least supportive work groups are most likely to feel unable to use these policies. Further, this sense of constraint is associated with lower organizational commitment. These findings suggest contradictions in the high-commitment model of employment as it has been applied to managers and professionals in the rapidly changing, competitive financial services industry.
Social Learning and Innovation at Retail Farmers' Markets*
Authors: Hinrichs C. Clare , Gillespie Gilbert W. , Feenstra Gail W.
Published: September 2004

Abstract  Retail farmers' markets are seen as key institutions in a more “civic agriculture,” but little is known about how they promote small business entrepreneurship. Drawing on research in economic sociology and economic geography, this paper examines the role of social learning in vendor innovation. Data from a 1999 mail survey of farmers' market vendors in California, New York and Iowa show that business innovation, as represented by intensity of vendors' innovative marketing practices and vendors' successful enterprise expansion, was modest. Social learning through engagement with customers contributed to more innovative marketing by vendors, while social learning through engagement with customers and fellow vendors increased the likelihood of vendors diversifying to additional markets beyond the farmers' market. Certain individual and enterprise characteristics also influenced vendor innovation. This suggests that, although important, the beneficial effects of social learning for vendors at farmers' markets remain moderated by human capital and structural factors.
Climbing the “Agricultural Ladder”: Social Mobility and Motivations for Migration in an Ecuadorian Colonist Community*
Authors: Bates Diane C. , Rudel Thomas K.
Published: September 2004

Abstract  During the early decades of the 20th century in the American Midwest young farming families achieved social mobility by moving up an ‘agricultural ladder’ through a series of rungs, from unpaid family work, to wage labor, to tenant farming, to a mortgaged farm, and, finally, to full ownership of a farm. In this paper we use the concept of an agricultural ladder to understand processes of social mobility in a Third World setting. A case study of a small rural community in the Ecuadorian Amazon reveals that while the young think in terms of an agricultural ladder, they see temporary labor migration to distant places, rather than local wage labor, as the only way that they can amass the capital necessary to purchase land and reach the top rung on the ladder.
On Farm and Packhouse: Employment at the Bottom of a Global Value Chain*
Authors: Dolan Catherine S.
Published: September 2004

Abstract The fresh vegetables commodity chain linking Kenyan producers with United Kingdom (UK) consumers employs significant numbers of workers in production and processing. This chain is dominated by UK retailers that determine the production imperatives of Kenyan firms upstream in the chain and, indirectly the employment strategies they adopt. This paper explores how competitive pressures are transmitted through the supply chain, and how exporters absorb these risks by placing greater emphasis on organizational flexibility and the elasticity of labor in horticultural production. The paper argues that while the industry provides substantial employment opportunities in Kenya, the commodity chain is dependent upon the “gendered” and insecure forms of employment it creates.
Female‐Headed Families and Poverty in Rural America*
Authors: Snyder Anastasia R. , McLaughlin Diane K.
Published: September 2004

Abstract  Employing data from the 1980, 1990, and 2000 March supplements of the Current Population Surveys, this study examines changing household and family structure in metro and nonmetro areas and corresponding changes in poverty, emphasizing female‐headed families with children under age 18. We also pay particular attention to the structure and economic conditions of subfamilies with children during this period. Household and family structure in suburban metro and nonmetro areas were quite similar by 2000. In contrast, families and households in nonmetro and metro central city areas were similar in their high prevalence of poverty. Finally, the risk of female‐headed families and subfamilies with children living in poverty is highest for nonmetro residents, and their individual characteristics suppress rather than account for this disadvantage. This pattern persisted across the decades studied, despite economic growth during the 1990s.
Bringing the “Moral Charge” Home: Fair Trade within the North and within the South*
Authors: Jaffee Daniel , Kloppenburg Jack R. , Monroy Mario B.
Published: September 2004

Abstract  Fair trade is typically understood as an alternative market system that aims to right historically inequitable terms of trade between the geopolitical North and South and foster more direct producer/consumer linkages. We suggest that a more expansive application of the term “fair trade” to encompass agro‐food initiatives within the North and South has considerable analytic and practical utility. We profile five such initiatives in the United States and two in Mexico. The U.S. undertakings are best understood as “proto‐” fair trade projects that frame their work principally as an effort to preserve “family farming” rather than as an exercise to achieve fairness in the marketplace. The Mexican initiatives more explicitly embrace the certification‐criteria‐labeling model of international fair trade. Both, we conclude, hold potential to harness fair trade's “moral charge” to improve conditions for small producers and laborers in North and South experiencing most directly the negative effects of economic globalization.
Mikroelem-terhelés hatása a közönséges televényféregre (Enchytraeus albidus)
Authors: Somogyi Zoltán , Bakonyi Gábor , Kádár Imre , Nagy Péter , Kiss István
Published: September 2004

Krónikus toxicitási vizsgálatokat végeztünk laboratóriumban a közönséges televényféreg (Enchytraeus albidus) faj segítségével egy 1991 tavaszán beállított mikroelem-terhelési szabadföldi tartamkísérlet szántott rétegébol származó talajokon. Hét elem - a Cd, Cr, Cu, Hg, Pb, Zn és a Se - hosszú távú hatásait teszteltük a faj mortalitásán és reprodukciós képességén. A kísérletben alkalmazott elemeknek (Cd, Cr, Cu, Hg, Pb, Zn, Se) a talajba kerülésüket követoen 7 évvel is van kimutatható hatása a toxicitási tesztekben vizsgált paraméterekre. Megállapítottuk, hogy a szelén növekvo koncentrációi a mortalitást és a reprodukciós képességet is szignifikánsan csökkentik. A vizsgált talajtípuson a LOEC érték 2 mg/kg NH4-acetát + EDTA-oldható Se volt. A legmagasabb koncentrációban (810 kg/ha) kijuttatott hat nehézfém (Cd, Cr, Cu, Hg, Pb, Zn) hét évvel a kezelés után a közönséges televényféreg mortalitására nincs statisztikailag igazolható hatással, ugyanakkor a reprodukciós képességet szignifikánsan csökkentik. Alacsonyabb koncentrációban (270 kg/ha) statisztikailag kimutatható hatása már csak a cinknek van, amely a reprodukciós képességet csökkenti.
Alföldi kunhalmok talaj-növény összefüggés-vizsgálata
Authors: Barczi Attila , Penksza Károly , Joó Katalin
Published: September 2004

Négy kunhalom (Pincés-halom, Kántor-halom, Hegyes-halom, Bökény-halom) botanikai és talajtani felvételezését végeztük el. A halmok növényzetének jellemzése érdekében a tipikus vegetációs egységekben cönológiai felvételeket készítettünk. Az általános botanikai vizsgálatok mellett a talaj-növény kapcsolatok értékelése érdekében a Kántor-halmon transzekt-felvételeket is készítettünk.  Összességében nemcsak a morfológiai vizsgálat mutatta hasonlónak az eltéro társulások talajviszonyait, hanem a vizsgált fizikai és kémiai talajjellemzok között sem találtunk olyan tényezot, amelyik egyértelmuvé tenné a vegetációváltást. Az eltéro társulások talajánál a pH-ban, CaCO3-tartalomban és fizikai féleségben nem tapasztaltunk eltérést. Eltérés a humusztartalomban, tápanyagokban és mintavételezéskori nedvességtartalomban mutatkozott.  A kutatást vízgazdálkodási és mikroklíma mérésekkel kívánjuk bovíteni.
A talajnedvesség-tartalom alakulása egy bükkös erdőben és benne kialakított lékekben
Authors: Hagyó Andrea , Rajkai Kálmán
Published: September 2004

Az erdészeti beavatkozásokkal együtt járó, a természetes lékdinamikát közelítő léknyitás talajnedvesség-tartalomra gyakorolt hatását tanulmányoztuk bükkös állományban, a Börzsöny hegységben. A K-ÉK-i kitettségű lejtőn elhelyezkedő, kb. 80 éves állományban 2000 telén létrehozott, kör alakú lékeket vizsgáltuk. A terület talaja andezit alapkőzeten kialakult, átlagosan 20-30 cm termőréteg-vastagságú, erodálódott agyagbemosódásos barna erdőtalaj. Feltételeztük, hogy a talajnedvesség-viszonyok a zárt lombkorona alatt és a lékekben különböznek. A talajnedvesség-mérések egy kis (kb. 20 m átmérőjű) és egy nagy (kb. 35 m átmérőjű) lékben, ill. környezetükben, vegetációs időszakban háromhetente és a vegetációs időszakon kívül összesen két alkalommal történtek transzekt, ill. grid elrendezésben. Kimutattuk, hogy a felső 10 cm-es talajréteg nedvességtartalma esős időszakok után kis mértékben különbözött a lékben és a zárt lombsátor alatt. Száraz időszakok után pedig szignifikánsan nagyobb volt a lékekben, mint az állomány alatt. A talajnedvesség-tartalom átlaga mindkét lékben minden mérési időpontban közel volt a szántóföldi vízkapacitás értékhez. Vizsgálatainkból arra következtettünk, hogy a lékek nyitása megváltoztatja a talaj felső rétegének nedvességviszonyait,  ahogy azt bükkös állomány lékeiben  leírták (pl. Bauhus, 1996). Méréseink szerint is a talaj a lékekben nedvesebb, mint a zárt lombsátor alatt. A két vizsgált lékméret hatása a talajnedvesség-tartalom nagyságára hasonló volt, míg a léken belüli térbeli mintázat különbözött. A lékhatás általánosabb érvényű jellemzéséhez a talajnedvesség-tartalom több lékben és hosszabb időn keresztül történő vizsgálatára van szükség. A méréseket a talajnedvesség-tartalmon kívül a fényre, mint abiotikus tényezőre is tervezzük kiterjeszteni.
Tápanyagellátás hatása az olajlen termésére, minőségére és elemfelvételére
Authors: Kádár Imre , Lukács Dánielné , László Sándorné
Published: September 2004

Karbonátos csernozjom vályogtalajon, egy mutrágyázási tartamkísérlet 14. évében vizsgáltuk az eltéro N-, P- és K-ellátottsági szintek és kombinációik hatását az olajlen (Szegedi-43 fajta) magtermésének olajtartalmára, zsírsavösszetételére, ásványi elemtartalmára és elemfelvételére. A termohely talaja a szántott rétegben mintegy 3% humuszt, 5% CaCO3-ot és 20% agyagot tartalmazott. A talaj oldható K, Mg, Mn és Cu elemekkel közepesen, P és Zn elemekkel gyengén ellátottnak minosült. A kísérlet 4N×4P×4K = 64 kezelést × 2 ismétlést = 128 parcellát foglalt magában. A fobb eredmények és következtetések: - Ezen a káliummal közepesen, foszforral gyengén ellátott termohelyen a P- és K-mutrágyázás érdemi terméstöbbleteket nem eredményezett. Optimális N-adagnak a 100 kg N/ha/év bizonyult. A 140-150 mg/kg ammónium-laktát (AL) oldható P2O5-tartalom, ill. 100 kg/ha/év N-trágyázás felett, az együttes NP-túlsúlyos kezelésekben az olajtartalom 3%-kal, a magtermés 25-30%-kal és az olajhozam 30-40%-kal csökkent. - A magtermés 1,2-2,0 t/ha, az olaj 38-41%, az olajhozam 453-789 kg/ha minimális (NP-túltrágyázás) és maximális értékeket mutatott a kezeléstol függoen. A mag olajában átlagosan 3,8% sztearinsav, 6,6% palmitinsav, 13,2% linolsav, 21,4% olajsav és 54,9% linolensav képzodött. A P-ellátás növelte, a N-trágyázás igazolhatóan mérsékelte a linolsav mennyiségét. Ellentétes irányú, de hasonló mértéku (4% körüli) változás állt be az olajsavtartalomban, azaz módosult a meghatározó linolensav/olajsav aránya. Igazolhatóan 10%-kal csökkent a linolsav mennyisége is az NP-túlsúlyos magban. - Az NP-túltrágyázás 10-12%-kal növelte a hulladék, ill. csökkentette a tiszta anyag mennyiségét a magtermésben. A csírázott magban 4-5%-kal igazolhatóan mérséklodött az ép csírák, ill. hasonló mértékben emelkedett a ki nem kelt rothadt csírák mennyisége. - Az extrém NP-túlsúlyos parcellákon nagyságrenddel nott a gyomborítottság és 20-30-szorosára emelkedett a hajtásokba épült makroelemek tömege. A K- 2-60, N- 2-34, Ca- 2-40, Mg- 0,3-6,8 és P-tartalom 0,2-4,3 kg/ha mennyiséget tett ki. A gyomok érdemi konkurensei lehetnek az olajlennek a talaj felveheto tápelemkészletének hasznosításában is. - A virágzás elott vett hajtásban a 2,5-3,5% N-, 0,30-0,45% P- és 1,5-2,5% K-koncentráció, ill. 8-10 N/P, 6-8 K/P és 1-2 N/K körüli arány lehet kívánatos, melyhez a termés, ill. olajhozam maximumai kötodtek. Adataink iránymutatóul szolgálhatnak a szaktanácsadás számára.  - A föld feletti betakarított termésbe aratáskor maximálisan 107 kg N, 44 kg K (53 kg K2O), 31 kg Ca, 9 kg Mg, 27 kg P (62 kg P2O5), 1-2 kg Na, 900 g Fe, 264 g Mn, 79 g Zn és 16 g Cu épült be. A fajlagos, azaz 1 t mag + a hozzá tartozó melléktermés (szár és tok) elemigénye az alábbi volt a kísérlet átlagában: 59 kg N, 32 kg P2O5, 26 kg K2O, 25 kg CaO, 8 kg MgO, 1,2 kg Na, 0,5 kg Fe, 135 g Mn, 45 g Zn, 9 g Cu. A szár + tok/magtermés aránya 1,63, a szár + tok + gyökér/mag aránya 1,93 volt átlagosan.
Futures and Forward Prices - Theory and Hungarian Experience
Authors: Radnai M.
Published: September 2004

Researchers have examined the difference between forward and futures prices since the introduction of futures contracts. In this paper we derive the explicit formula for stock-index futures prices under the assumptions of lognormal asset prices, determine the relative difference between futures and forward prices, and test the model for BUX contracts traded on the Budapest Stock Exchange between 1997 and 2002.
Effect of melatonin on biochemical variables of the blood in dairy cows
Authors: Darul Katarzyna , Kruczyńska Helena
Published: September 2004

In order to examine the effect of exogenous melatonin on selected biochemical variables of the blood in ruminants, dairy cows were given the pineal gland hormone in the dose of 0.1 mg/kg body weight. One and four hours after melatonin administration blood samples were collected from the cows in the control and the treated group in order to determine the levels of glucose, insulin, total cholesterol, triglycerides, free fatty acids, as well as the activities of alanine and aspartate aminotransferase. The pineal gland hormone caused a significant increase in the levels of total cholesterol and triglycerides, slight increases in glucose and insulin levels, and a significant decrease in the concentration of free fatty acids. Melatonin did not exert an effect on the activity of liver enzymes.
Effect of supplementation with methionine and different fat sources on the glutathione redox system of growing chickens
Authors: Németh Katalin , Mézes M. , Gaál T. , Bartos Á. , Balogh K. , Husvéth F.
Published: September 2004

The effect of supplementary methionine and fats of different saturation levels on the glutathione redox system of growing broiler cockerels was studied. The diet of three groups of chicks was supplemented with corn germ oil, beef tallow and fish oil at the levels of 30 g/kg and 50 g/kg of feed, respectively. The diet of further three groups was supplemented with methionine (5 g/kg of feed) in addition to the different fat sources. Control chicks were fed with a compound feed without methionine and fat supplementation. Reduced glutathione (GSH) and glutathione disulphide (GSSG) content as well as glutathione peroxidase activity in the liver were determined and GSH/GSSG ratio was calculated at day old and then at one and three weeks of age. Our results indicate that supplementary methionine stimulates both the synthesis of the glutathione redox system and glutathione peroxidase activity in growing chickens in the first period of postnatal life, when the risk of lipid peroxidation is high due to feeding unsaturated fats in the diet.
Comparative study of biochemical methods for the identification of Dichelobacter nodosus
Authors: Jiménez Ruth , Píriz S. , Mateos E. M. , Vadillo S.
Published: September 2004

The aim of this study was to compare four identification procedures to detect Dichelobacter nodosus and develop a rapid, simple and effective method to identify D. nodosus strains isolated from cases of ovine footrot. The four methods used were: (a) the classic guidelines set down by Holdeman et al. (1977) and Summanen et al. (1993) which are based on gas liquid chromatography (GLC) and different biochemical tests, this method was considered as landmark; (b) Baron and Citron's flowchart for the rapid identification of Gram-negative rod-shaped anaerobes (1997); (c) the API rapid 32 A system (bio Mérieux), and (d) Mast ID™ Anaerobe ID Ring (MID8) (Mast Diagnostics). None of the four methods used allowed us to correctly identify the D. nodosus strains (neither the strains isolated from cases of ovine footrot nor those originating from type collection). Because of the difficulties encountered in obtaining a correct identification of D. nodosus, we propose a simple, rapid and effective way to achieve this task. Our flowchart will provide the means to identify this microorganism in any laboratory of general microbiology without having to use any specialised equipment.
Soybean: feed quality and safety. Part 1: Biologically active components. A review
Authors: Csáky I. , Fekete S.
Published: September 2004

A large number of soybean components have diverse biological activities. These include hormonal, immunological, bacteriological and digestive effects. The presently known allergens are listed. The divergence between chemical evaluation and biological value is highlighted. The following components are discussed: Kunitz inhibitor, Bowman-Birk inhibitor, saponins, soyacystatin, phytoestrogens (daidzein, glycitein, genistein), Maillard products, soybean hydrophobic protein, soy allergens, lecithin allergens, raffinose, stachyose, 2-pentyl pyridine. The studies describing the effects of the isolated components are reviewed.
Soybean: feed quality and safety. Part 2: Pathology of soybean feeding in animals. A review
Authors: Csáky I. , Fekete S.
Published: September 2004

Various animal models in farm and laboratory animals indicate the possible pathological effect of soybean feeding. Immunity and tolerance to oral soybean intake and a generalised meta-model of effects are discussed. It seems that FAO/WHO recommendations will have to be considered in assessing the biological value of soybean feed sources. Determination of hull content, antigenic potential, conglycinin and trypsin inhibitor content is warranted in view of the future component pricing of soybean meals.
Immunohistochemical investigation of cerebellum in dogs infected with canine distemper virus
Authors:   Nalan Kabakci,   Murat Yarim,   Siyami Karahan,   Tolga Guvenc,   Burahan Bekir Yagci,   I. Safa Gurcan
Published: September 2004

The cerebella of 21 dogs with canine distemper virus (CDV) infection and four normal dogs were examined histopathologically and immunohistochemically. Cerebella of CDV-infected dogs showed nonsuppurative demyelinating encephalomyelitis, classified as acute, subacute or chronic. Immunolocalisation of CDV antigen also confirmed the infection. Tissues were examined for co-localisation of the CDV antigen with either an astrocyte-specific marker, glial fibrillary acidic protein (GFAP), or an oligodendrocyte-specific marker, galactocerebroside (GalC). Immunoreactive cells were counted in demyelinating areas of the white matter. The number of astrocytes (GFAP positive) was significantly (p < 0.05) higher in CDV-infected dogs compared to controls. In contrast, the number of oligodendrocytes (GalC positive) was significantly (p < 0.001) lower in CDV-infected dogs and was much lower in chronic cases (p < 0.05). Approximately 41% of astrocytes and 17% of oligodendrocytes were immunoreactive for CDV. The ratio of CDV-infected oligodendrocytes and astrocytes remained almost constant during the progression of the disease (P ≯ 0.05). In conclusion, CDV infects both astrocytes and oligodendrocytes. The gradual loss of oligodendrocytes is most likely responsible for the progressive demyelination in CDV infection. Astrocytosis in CDV infection should be further investigated if it occurs to stimulate oligodendrocytes for myelin production to compensate for the loss or to induce oligodendrocyte degeneration.
75 éves a Magyar Pszichológiai Társaság
Authors: Hunyady György
Published: September 2004

A Magyar Pszichológiai Társaság ünnepi közgyűlésén tartott előadás folytatja a magyar pszichológia múltjának felderítését. Rendszeresen áttekinti, hogy a magyar társadalom történetének egymást követő nyolc szakasza milyen korlátokat szabott a pszichológia fejlődésének, és milyen akadályokat gördített útjába az 1920-as évektől kezdődően, a második világháborút követően, a rendszerváltás utáni évtizeddel bezáróan. A kontraszelekciós hatásokkal azonban az egyetemi és akadémiai keretekben intézményesedő tudományág sikerrel birkózott meg. Tükrözik ezt - arányosan nyolc pozitívum - többek között a magyar tudósok külföldi sikerei, a hazai pszichológia előrevivő szemléleti sajátosságai, a szakterület egészséges generációs összetétele, publikációs termése, a képzést megújító reformjai, valamint a Társaság betöltött missziója.
A szülőkhöz való kötődés és az óvodai társas kapcsolatok
Authors: Inántsy-Pap Judit , Máth János
Published: September 2004

A családi tapasztalatok kortárskapcsolatokra kiterjedő hatásának kutatásában tradicionálisnak tekinthető alternatíva a kötődéselmélet. A csecsemőkori biztonságos kötődés feltételezhető előnyeit a későbbi társas kapcsolatokra vonatkozóan sok empirikus kutatás választotta tárgyául. Az ilyen jellegű, korai kötődési konstellációból kiinduló vizsgálatok adatai azonban, főleg hosszabb távú előrejelzés esetén, nem voltak mindig konzisztensek, előfordultak ellentmondásos eredmények, és olyanok is, amelyek igen gyenge korrelációt találtak a korai kötődés és a későbbi társas kapcsolatok alakulása között. Az ellentmondásos eredmények a korai kötődési mintázat stabilitásának és folytonosságának problémáját vetik fel. A kötődési biztonság és a társas kapcsolatok azonos életkorban történő vizsgálatával azonban a korai kötődési mintázatok stabilitásának problémája elkerülhető. Jelen vizsgálat célja, hogy azonos idejű méréseket alkalmazva két egymástól független mintán is megvizsgálja a szülőkhöz való kötődési biztonság szerepét az óvodás gyerekek társas kapcsolatainak kialakulásában. Két településen, Nyíregyházán és Tiszaújvárosban végeztünk vizsgálatokat, összesen 143 gyerek részvételével, életkoruk 5, 5 és fél év.  A társas helyzet azonosítására használatos dimenziók közül konkrétan a népszerűség, az elutasítás, a baráti kapcsolatok és a magányosság a vizsgálat tárgya. A kötődési biztonság mérésére a Szeparációs szorongás teszt Seattle verzióját használtuk (Slough, Greenberg, 1988). A gyerekek társas helyzetének azonosítását pedig szociometrikus eljárással végeztük.  Eredményeink mintától függetlenül demonstrálják a kötődési biztonság szerepét a társas kapcsolatok alakulásában. Az elutasítás kivételével minden a társas helyzet mérésére használt változó esetében kimutatható a kötődési biztonság mértéke és a társas helyzet alakulása közötti összefüggés.
Az erkölcsi ítélet keletkezése: a vétség súlyossága és az erkölcsi jelleg
Authors: Vajda Zsuzsanna
Published: September 2004

A tanulmány az erkölcsi fejlődés területspecifikus elméletével kapcsolatos vitákat, a kutatás újabb irányait, valamint a szerző saját kutatásait mutatja be. A területspecifikus megközelítés a bírálók szerint nem oldotta meg az erkölcsi szabályszegés definíciós problémáit. Továbbra is tisztázatlan az erkölcs metafizikai háttere, illetve a racionális megfontolásnak az erkölcsi döntésben játszott szerepe, bár e kérdések Turiel, Nucci és munkatársai 1990-es években végzett kutatásaiban is nagy súllyal szerepelnek. Saját kutatásaim két szakaszra tagolhatók: az első szakaszban elvégeztem a területspecifikus elmélet standard kísérleteit a kutatók által eredetileg is alkalmazott módszerekkel, gyerekek körében. A kutatásban alkalmazott módszer gyengesége, hogy az ítélet erkölcsi jellege és a súlyosság mértéke szétválaszthatatlanul egybeolvad. A másik probléma, hogy a kutatás előfeltevése nem tartalmazza a sok évszázados kulturális tapasztalatot, amelynek megfelelően valódi erkölcsi döntés csak a komplex racionális mérlegelésre képes felnőttektől várható. A kutatás második szakaszában felnőttek ítéleteit vizsgáltam, verbális dilemmák segítségével, a területspecifkus megközelítés módszertani elvei alapján. A dilemmák különböző formájú expozíciója alapján adott válaszok segítségével sikerült részlegesen különválasztani a súlyosság és az erkölcsi jelleg megítélését. Az eredmények azt is megmutatták, hogy a gyerekek és a felnőttek erkölcsi döntései valóban különböznek. A gyerekek élettapasztalata és gyengébb formállogikai képességei nem teszik lehetővé a szabályszegések komplex értékelését, ezért az elvont értéktartalmat tekintik alapnak, míg a felnőttek tekintetbe veszik a cselekvő szándékát és a szabályszegés következményeit is.
Molecular genetics of the ichthyoses
Authors: Richard Gabriele
Published: September 2004

The ichthyoses are a large, clinically, genetically, and etiologically heterogeneous group of disorders of cornification due to abnormal differentiation and desquamation of the epidermis. Although they differ in clinical features, inheritance, and structural and biochemical abnormalities of the epidermis, they often pose a diagnostic challenge. For each of the 12 ichthyoses and related disorders described here, the major disease genes have been identified and genotype–phenotype correlation have begun to emerge. The molecular findings reveal the functional importance and interactions of many different epidermal proteins and metabolic pathways, including major structural proteins (keratins, loricrin), enzymes involved in lipid metabolism (transglutaminase 1, lipoxygenases, fatty aldehyde dehydrogenase, steroid sulfatase, glucocerebrosidase, Δ8‐Δ7 sterol isomerase, 3β‐hydroxysteroid dehydrogenase), and protein catabolism (LEKTI), peroxisomal transport and processing (Peroxin 7 receptor, Phytanoyl‐CoA hydroxylase) and DNA repair (proteins of the transcription repair complex). This review highlights the spectacular advances in the molecular genetics and biology of heritable ichthyoses over the past decade. It illustrates the power of molecular diagnostics for refining disease classification, providing prenatal diagnosis, improving genetic counseling, and clinical management. © 2004 Wiley‐Liss, Inc.
Genetics of pigmentary disorders
Authors: Tomita Yasushi , Suzuki Tamio
Published: September 2004

The genetic and molecular bases of various types of congenital pigmentary disorders have been classified in the past 10 years, as follows: (1) disorders of melanoblast migration in the embryo from the neural crest to the skin: piebaldism; Waardenburg syndrome 1–4 (WS1–WS4); dyschromatosis symmetrica hereditaria. (2) Disorders of melanosome formation in the melanocyte: Hermansky–Pudlak syndrome 1–7 (HPS1–7); Chediak–Higashi syndrome 1 (CHS1). (3) Disorders of melanin synthesis in the melanosome: oculocutaneous albinism 1–4 (OCA1–4). (4) Disorders of mature melanosome transfer to the tips of the dendrites Griscelli syndrome 1–3 (GS1–3). These disorders are presented and their gene mutations and pathogenesis are discussed. © 2004 Wiley‐Liss, Inc.
Effects of arsenobetaine, a major organic arsenic compound in seafood, on the maturation and functions of human peripheral blood monocytes, macrophages and dendritic cells
Authors: Ohta Takami , Sakurai Teruaki , Fujiwara Kitao
Published: September 2004

We examine the in vitro immunotoxicity of synthetically pure arsenobetaine [AsBe; trimethyl (carboxymethyl) arsonium zwitterion], which is a major organic arsenic compound in seafood, on various human immune cells, such as peripheral blood monocytes, monocyte‐derived macrophages and monocyte‐derived dendritic cells (DCs). In particular, we examine the differentiation of monocytes into macrophages or DCs by comparing the effects of AsBe with those pentavalent inorganic arsenate. AsBe neither enhanced nor inhibited the differentiation of human monocytes into macrophages or DCs, and also did not affect their various immune functions. Furthermore, AsBe had no cytolethality in monocyte‐derived macrophages or DCs even at a concentration of 5 mmol l−1. In contrast, inorganic arsenate showed strong cytolethality in these human immune cells in vitro at micromolar concentrations. These data indicate that the organic arsenic compound AsBe in seafood has no in vitro immunotoxicity in human immune cells. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of humic substances and soya lecithin on the aerobic bioremediation of a soil historically contaminated by polycyclic aromatic hydrocarbons (PAHs)
Authors: Fava Fabio , Berselli Sara , Conte Pellegrino , Piccolo Alessandro , Marchetti Leonardo
Published: September 2004

The high hydrophobicity of polycyclic aromatic hydrocarbons (PAHs) strongly reduces their bioavailability in aged contaminated soils, thus limiting their bioremediation. The biodegradation of PAHs in soils can be enhanced by employing surface‐active agents. However, chemical surfactants are often recalcitrant and exert toxic effects in the amended soils. The effects of two biogenic materials as pollutant‐mobilizing agents on the aerobic bioremediation of an aged‐contaminated soil were investigated here. A soil historically contaminated by about 13 g kg−1 of a large variety of PAHs, was amended with soya lecithin (SL) or humic substances (HS) at 1.5% w/w and incubated in aerobic solid‐phase and slurry‐phase reactors for 150 days. A slow and only partial biodegradation of low‐molecular weight PAHs, along with a moderate depletion of the initial soil ecotoxicity, was observed in the control reactors. The overall removal of PAHs in the presence of SL or HS was faster and more extensive and accompanied by a larger soil detoxification, especially under slurry‐phase conditions. The SL and HS could be metabolized by soil aerobic microorganisms and enhanced the occurrence of both soil PAHs and indigenous aerobic PAH‐degrading bacteria in the reactor water phase. These results indicate that SL and HS are biodegradable and efficiently enhance PAH bioavailability in soil. These natural surfactants significantly intensified the aerobic bioremediation of a historically PAH‐contaminated soil under treatment conditions similar to those commonly employed in large‐scale soil bioremediation. © 2004 Wiley Periodicals, Inc.
Energy‐efficient growth of phage Qβ in Escherichia coli
Authors: Kim Hwijin , Yin John
Published: September 2004

The role of natural selection in the optimal design of organisms is controversial. Optimal forms, functions, or behaviors of organisms have long been claimed without knowledge of how genotype contributes to phenotype, delineation of design constraints, or reference to alternative designs. Moreover, arguments for optimal designs have been often based on models that were difficult, if not impossible, to test. Here, we begin to address these issues by developing and probing a kinetic model for the intracellular growth of bacteriophage Qβ in Escherichia coli. The model accounts for the energetic costs of all template‐dependent polymerization reactions, in ATP equivalents, including RNA‐dependent RNA elongation by the phage replicase and synthesis of all phage proteins by the translation machinery of the E. coli host cell. We found that translation dominated phage growth, requiring 85% of the total energy expenditure. Only 10% of the total energy was applied to activities other than the direct synthesis of progeny phage components, reflecting primarily the cost of making the negative‐strand RNA template that is needed for replication of phage genomic RNA. Further, we defined an energy efficiency of phage growth and showed its direct relationship to the yield of phage progeny. Finally, we performed a sensitivity analysis and found that the growth of wild‐type phage was optimized for progeny yield or energy efficiency, suggesting that phage Qβ has evolved to optimally utilize the finite resources of its host cells. © 2004 Wiley Periodicals, Inc.
Heterogeneous conditions in dissolved oxygen affect N‐glycosylation but not productivity of a monoclonal antibody in hybridoma cultures
Authors: Serrato J. Antonio , Palomares Laura A. , Meneses‐Acosta Angélica , Ramírez Octavio T.
Published: September 2004

It is known that heterogeneous conditions exist in large‐scale animal cell cultures. However, little is known about how heterogeneities affect cells, productivities, and product quality. To study the effect of non‐constant dissolved oxygen tension (DOT), hybridomas were subjected to sinusoidal DOT oscillations in a one‐compartment scale‐down simulator. Oscillations were forced by manipulating the inlet oxygen partial pressure through a feedback control algorithm in a 220‐mL bioreactor maintained at a constant agitation. Such temporal DOT oscillations simulate spatial DOT gradients that can occur in large scales. Different oscillation periods, in the range of 800 to 12,800 s (axis of 7% (air saturation) and amplitude of 7%), were tested and compared to constant DOT (10%) control cultures. Oscillating DOT decreased maximum cell concentrations, cell growth rates, and viability indexes. Cultures at oscillating DOT had an increased glycolytic metabolism that was evidenced by a decrease in yield of cells on glucose and an increase in lactate yield. DOT gradients, even several orders of magnitude higher than those expected under practical large‐scale conditions, did not significantly affect the maximum concentration of an IgG1 monoclonal antibody (MAb). The glycosylation profile of the MAb produced at a constant DOT of 10% was similar to that reported in the literature. However, MAb produced under oscillating culture conditions had a higher amount of triantennary and sialylated glycans, which can interfere with effector functions of the antibody. It was shown that transient excursions of hybridomas to limiting DOT, as occurs in deficiently mixed large‐scale bioreactors, is important to culture performance as the oscillation period, and thus the time cells spent at low DOT, affected cell growth, metabolism, and the glycosylation pattern of MAb. Such results underline the importance of monitoring protein characteristics for the development of large‐scale processes. © 2004 Wiley Periodicals, Inc.
Computer programs for temperature in fins and slab bodies with the method of Green's functions
Authors: Cole Kevin D.
Published: September 2004

Heat conduction in fins and slab bodies, a traditional undergraduate topic, is treated with the Green's function (GF) method. A variety of boundary conditions and heating conditions are included. Computer programs are described which are designed to improve student learning of the GF method. The programs are available from the author. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 189–197, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20010
Experimenting with a computer‐mediated collaborative interaction model to support engineering courses
Authors: Fuller David A. , Moreno Andres F.
Published: September 2004

Many of the engineering education lecture courses are taught only with the support of a board or transparencies. In both cases, the students have to copy the material passed in class, including additional annotations and comments. We performed a controlled experiment to measure the impact of the insertion of a computer mediated collaborative interaction model to support the teaching/learning process in such scenarios, using a Web‐based computer application. Our experiment was done during two consecutive semesters of a First Year Programming Engineering course, with 447 enrolled students where 234 students were surveyed. In this paper, we describe the design and execution of the experiment, and show the obtained results. Based on our results, we conclude that there are advantages of using a collaborative interaction model supported by a collaborative software tool in an Engineering course such as the experimented. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 175–188, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20012
A learning model based on a didactic cognitive approach: The case of single‐degree‐of‐freedom systems
Authors: Laureano‐Cruces Ana Lilia , Terán‐Gilmore Amador , Arriaga Fernando de
Published: September 2004

Aiding the acquisition of cognitive abilities is an important issue within the teaching–learning process. The student should not only control his/her own learning process, but also the way he/she does it. One of the new developments in education, focused on achieving those goals, is the use of tools, models, and techniques derived from cognitive psychology to improve the design of course “curricula” within a specific knowledge domain. The paper presents a learning model that focuses on a specific topic, and uses a cognitive approach for building human expert mental models and schemes, partially based on the concepts of Forbus' qualitative theory. Regarding the didactic approach, the authors' experience is taken into account within a “student centered” learning approach, in which training or learning systems have a great significance. All these elements are integrated in the formulation of an intelligent learning prototype, now under construction, that fosters a qualitative understanding of the domain, before the quantitative part is dealt with. The selected domain is a specific topic of structural dynamics known as single‐degree‐of‐freedom (SDOF) systems. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 152–164, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20013
A set of microprocessor‐based procedures for an industrial engineering course
Authors: González E. J. , Hamilton A. , Moreno L. , Marichal R. L. , Torres S.
Published: September 2004

Nowadays, microprocessors have become an essential tool in a widely set of industrial applications. Because of this, Engineering students, especially Industrial Engineering ones, should be properly taught in its use by implementing sufficiently interesting procedures. The authors consider that these procedures should allow students to manage most of the features that a standard microprocessor offers, such as I/O ports, timer counters, serial communication, or external interruptions. In this way, this article describes a wide and reasonable‐priced set of microprocessor‐based procedures that forces Industrial Engineering students to be familiarized with the described features. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 145–151, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20015
Development of low‐cost data acquisition hardware as an undergraduate capstone senior design project
Authors: Thompson Elizabeth A. , Acierto Jonathon , Chavis Adrian
Published: September 2004

This paper discusses a capstone senior design project involving development of a data acquisition system for gaining understanding of digital signal processing at the level of hardware architecture. The Pentium II PC‐based design includes a microphone with corresponding conditioning circuitry, an analog‐to‐digital converter, an 8255 peripheral interface adapter, a MATLAB® interface, a digital‐to‐analog converter, and speakers. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 198–207, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20016
Enantioselective Conjugate Addition of Dialkylzinc and Diphenylzinc to Enones Catalyzed by a Chiral Copper(I) Binaphthylthiophosphoramide or Binaphthylselenophosphoramide Ligand System
Authors: Shi Min , Wang Chun‐Jiang , Zhang Wen
Published: September 2004

The enantioselective conjugate addition of dialkylzinc or diphenylzinc to enones was catalyzed by a copper(I)‐axially chiral binaphthylthiophosphoramide or binaphthylselenophosphoramide ligand system at room temperature (20 °C) or 0 °C, affording the Michael adducts in high yields with excellent ee for cyclic and acyclic enones. The enantioselectivity and reaction rate achieved here are one of the best results yet for the Cu‐catalyzed conjugate addition to enones. It was revealed that this series of chiral phosphoramides was a novel type of S,N‐bidentate ligands on the basis of 31P NMR and 13C NMR spectroscopic investigations. The mechanism of this asymmetric conjugate addition system has been investigated as well. We found that the acidic proton of phosphoramide in these chiral ligands play a significant role in the formation of the active species. A bimetallic catalytic process has been proposed on the basis of previous literature. The linear effect of product ee and ligand ee further revealed that the active species is a monomeric CuI complex bearing a single ligand [CuI:ligand 1:1].
Valence Electron Rules for Three‐ and Four‐Membered Atomic Rings: High‐Row Representative Elements.
Authors: Ding Yi‐hong , Takeuchi Kunihiro , Inagaki Satoshi
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.
Vibrational Study and Crystal Structure Refinement of BaHPO4.
Authors: BenChaabane Tahar , Smiri Leila , Bulou Alain
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.
Cathodoluminescence and Photoluminescence Properties of CaS Thin Film Codoped with Pb and Cu.
Authors: Choi Sung‐Ho , Park Chong‐Ook , Park Hyung‐Sang , Park Sang‐Hee Ko , Yun Sun Jin
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.
Strong Near‐Infrared Luminescence in BaSnO3.
Authors: Mizoguchi Hiroshi , Woodward Patrick M. , Park Cheol‐Hee , Keszler Douglas A.
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Colloidal Mn2+: ZnO Quantum Dots and High‐Tc Ferromagnetic Nanocrystalline Thin Films.
Authors: Norberg Nick S. , Kittilstved Kevin R. , Amonette James E. , Kukkadapu Ravi K. , Schwartz Dana A. , Gamelin Daniel R.
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.
Room‐Temperature Ferroelectricity in Strained SrTiO3.
Authors: Haeni J. H. , et al. et al.
Published: September 2004

For Abstract see ChemInform Abstract in Full Text.