bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on the Fluorescence Quenching of Eosin by certain Organic Dyes
Authors: Kathiravan A. , Anbazhagan V. , Asha Jhonsi M. , Renganathan R.
Published: September 2008

The fluorescence quenching of Eosin by certain dyes has been investigated using steady state technique. The dyes used are Uniblue-A, Acid blue 129, Alizarin, Alizarin red S, Erichrome Black T, Tartrazine, Methyl orange, Methyl red, Acid orange 63, Congo red. The quenching was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear in the range of quencher concentration used [0−5×10−
5] M. The quenching rate constant (k

q
) is in the range of 0.85–26.65×1012 M−
1s−
1. The quenching mechanism is discussed on the basis of the quenching rate constants as well as the reduction potential of the dyes. Rehm-Weller equation is applied for the calculation of free energy change (ΔGet).
Structural Investigations on Nanocomposite Mixed Metal Oxide Powders Used in Surface Catalysis
Authors: Krishnan Venkata , Heislbetz Sandra , Bertagnolli Helmut
Published: September 2008

Structural investigations were performed on catalytically active WO3/CeO2 and CeO2/yttria stabilised zirconia (YSZ) nanocomposite mixed metal oxide powders, by means of extended X-ray absorption fine structure (EXAFS) and Raman spectroscopy. In the case of WO3/CeO2 nanocomposites, WO3 in varying compositions, were supported on CeO2 and in the CeO2/YSZ nanocomposites, CeO2 in different compositions, were supported on YSZ. Wet impregnation technique was used for the preparation of samples in both the cases. The EXAFS and Raman investigations on WO3/CeO2 nanocomposites show that the structure of the different WO3/CeO2 nanocomposites is similar to that of crystalline CeO2 and WO3 doping does not modify the local environment around the cerium atoms. The studies on CeO2/YSZ nanocomposites reveal that the YSZ retains its structural integrity even after doping with CeO2. Hence the studies on the ceria containing two different nanocomposite mixed metal oxide powders indicate that there is no diffusion of the doped oxides into the metal oxide support. Therefore, it is confirmed that the dopant is only on the surface of the support material.
Thermodynamic and Transport Behavior of Binary Liquid Mixtures of 1-Decanol with Hexadecane and Squalane at 298.15, 303.15 and 308.15 K
Authors: Dubey Gyan P. , Sharma Monika
Published: September 2008

This paper presents densities, ρ, speeds of sound, u and viscosities, η of pure 1decanol, C10H21OH, hexadecane, C16H34, squalane (2,4,6,10,15,19,23-hexamethyltetraco- sane), C30H62 and their binary liquid mixtures, with 1-decanol, C10H21OH as a common component, over the whole composition range at 298.15, 303.15 and 308.15 K. The excess molar volume, V

m

E
, excess molar isentropic compressibility, K

E

S

,

m
, deviation of the speed of sound, u

D
, from their ideal values u

id
in an ideal mixture, and viscosity deviation, Δη were calculated from experimental data. The apparent molar volumes, Φ

v

,

i
and apparent molar isentropic compressibilities, Φ

k

,

i
were also calculated. The values of Φ

v

,

i
and Φ

k

,

i
were used to estimate the partial molar volumes and partial molar isentropic compressibilities at infinite dilution, ߙV¯ Φ,i

0 and ߙK¯ Φ,i

0, respectively. Apart from using density data for calculating V

m

E
, excess molar volumes have also been estimated by using Prigogine-Flory-Patterson (PFP) theory.
Experimental and Quantum Chemical Study of the Oxidation Mechanism of CF2CFBr by O2
Authors: Badenes M.P. , Czarnowski Joanna , Cobos Carlos J.
Published: September 2008

The oxidation mechanism of bromotrifluoroethylene, CF2CFBr, by molecular oxygen has been investigated in the gas phase at 416 and 460 K. Based on the CF2CFBr consumption, the yields of the principal product CF2BrC(O)F were 77% and 70% at 416 and 460 K, respectively. Smaller amounts of CF2O, CFBrO and only traces of CF3C(O)F and CO2 were also formed. In the absence of O2, no consumption of CF2CFBr was observed. The oxidation follows a chain mechanism propagated by Br atoms. The energetics of the relevant reaction pathways was studied using different density functional theory methods including more accurate high-level G3 ab initio calculations. The studies revealed that the oxidation is initiated by attack on the carbon atom of the CF2 group of CF2CFBr by the O2. The predicted activation energy for this process is 26.6 kcal mol–1. All other electronic energy barriers and reaction intermediates are below the reagents energy. The theoretical calculations support the proposed reaction mechanism based on previous experimental studies.
Gene expression and secretion of LH and FSH in relation to gene expression of GnRH receptors in the brushtail possum (Trichosurus vulpecula) demonstrates highly conserved mechanisms
Authors: Crawford J L , Heath D A , Haydon L J , Thomson B P , Eckery D C
Published: September 2008

In eutherian mammals, the gonadotrophins (LH and FSH) are synthesized and stored in gonadotroph cells under the regulation of multiple mechanisms including GnRH. Very little is known about the regulation of gonadotrophin secretion and storage in pituitary glands of marsupials. This study revealed, using quantitative PCR and heterologous RIA techniques, thatLHBmRNA expression levels remained constant over the oestrous cycle, regardless of the presence of a preovulatory LH surge, which is characteristic of a hormone secreted under regulation. Our sampling regime was unable to detect pulses of LH during the follicular phase, althoughGNRHRmRNA levels had increased at this time. Pulses of LH were, however, detected in the luteal phase of cycling females, in anoestrus females and in males. There was a positive correlation between gene expression ofFSHBand plasma levels of FSH at different stages of the oestrous cycle and no pulses of FSH were detected at any time; all characteristics of a hormone secreted via the constitutive pathway. Usingin situhybridisation and immunohistochemistry methods, we determined that mRNA expression ofLHBandFSHB, and protein storage of gonadotrophins exhibited a similar pattern of localisation within the pituitary gland. Additionally, sexual dimorphism of gonadotroph populations was evident. In summary, these findings are similar to that reported in eutherians and considering that marsupial evolution diverged from eutherians over 100 million years ago suggests that the regulation of gonadotrophins is highly conserved indeed.
Effect of sowing date and N fertilisation on the yield and yield stability of maize ( Zea mays L.) hybrids in a long-term experiment
Authors: Berzsenyi Z. , Dang Q.
Published: September 2008

The effect of sowing date, N fertilisation and genotype on the grain yield and yield stability of maize was studied between 1991 and 2006 in a long-term N fertilisation experiment set up on chernozem soil in Martonvásár, Hungary. The N treatments (0, 60, 120, 180 and 240 kg ha−1) represented the main plot of the three-factor, split-split-plot experiment, with the sowing date (early, optimum, late, very late) in the sub-plots and hybrids from different maturity groups in the sub-sub-plots. The highest yields were obtained for the early and optimum sowing dates (8.712 and 8.706 t ha−1). Compared with the optimum sowing date, a delay of ten or twenty days led to yield losses of 5% and 12.5%, respectively. In the late and very late sowings and in years with unfavourable weather conditions, yield increments were only observed up to an N rate of 60 kg ha−1, while in the early and optimum sowings and in favourable years yield increments were significant up to 120 kg ha−1N. Yield stability was smallest in the early and very late sowings, in the control and for high N rates, and in the early and late maturity hybrids. It can be concluded that high yields and yield stability are not mutually exclusive.
Histological aspects of the cryopreservation of potato
Authors: Pepó P. , Kovács A.
Published: September 2008

Cryopreservation appears to be a suitable solution for the maintenance of potato germplasms. The protocol described in this paper can be applied for the vitrification and preservation of meristems. During histo-cytological studies it is possible to observe modifications at the cellular level and to understand the adaptive mechanism to low temperatures. Control potato meristem tissue contained a number of meristematic cells with a gradient of differentiation. After freezing there were a large number of vacuolated cells, some of which exhibited broken cell walls and plasmolysis. The thickening of the cell wall, giving them a sinuous appearance, was observed after freezing and thawing the meristems, with ruptures of the cuticle and epidermal layer.
Effect of different nutrient levels on the resistance of soybean to Macrophomina phaseolina infection in field experiments
Authors: Csöndes I. , Balikó K. , Dégenhardt A.
Published: September 2008

Field experiments were carried out with soybean [
Glycine max
(L.) Merrill] on a Haplic Chernozem soil. Eleven treatment combinations were applied with increasing rates of fertilizers in three replicates. At full maturity the dry weight production, total biomass production, root weight, yield, shoot NPK concentration and severity of
Macrophomina phaseolina
infection were determined. The highest degree of
Macrophomina
infection was found in the lowest NPK treatment, while the lowest rate of disease was observed for the highest NPK combination. By increasing the NK supply, the degree of infection decreased. At the same fertilizer rates, significantly lower infection was observed at higher phosphorus levels. The dry weight production, total biomass production of the shoots, pod weight and nitrogen concentration of the shoots were negatively correlated with the rate and severity of infection, which was positively correlated with the concentration of phosphorus. No correlation was found between root weight and infection or between potassium concentration and infection.
Results of a 30-year-old fertilisation experiment
Authors: Füleky G.
Published: September 2008

The long-term mineral fertilisation experiment set up on acidic brown forest soil in Gödöllő in 1972 has made it possible over the years to answer a number of questions. It became clear that, in general, increasing rates of NPK fertilisation only caused a significant increase in the yields obtained in the crop rotation at lower rates (150–300 kg NPK/ha). As time went on, rates higher than this caused yield depression. The continuous application of high fertiliser rates led to a substantial increase in the P and K contents of the ploughed layer and in the quantity of nitrate accumulating in the 3 m soil profile. An increase in the quantity of nutrients was associated with a reduction in the pH and in the content of Ca and Mg. When mineral fertilisation was omitted for six years, there was a substantial reduction in the P and K contents of the ploughed layer.
Effect of organics on nitrogen transformations in soil under different moisture regimes
Authors: Mavi M. , Singh B. , Setia R.
Published: September 2008

Awareness of the environmental aspects of the quality of crop production has increased in recent decades, leading to renewed interest in organics such as crop residues, green manures and organic manures. The effect of organics on urea transformation was investigated by conducting a laboratory incubation experiment in alluvial clay loam soil (Typic Ustifluvents) at 33±1°C with two moisture levels (1:1 soil:water ratio and field capacity). The rate of urea hydrolysis decreased as the time of incubation increased and the disappearance of urea N was associated with a corresponding increase in the (NH
4+
+ NO
3−
)-N content in soils treated with crop residues (rice straw and wheat straw), organic manures (poultry manure and farmyard manure) and green manures (cowpea and sesbania). In untreated soil, the time taken for the complete hydrolysis of the applied urea (200 μg urea N g
−1
soil) was more than 96 h at both the moisture levels, whereas in amended soils it was completed in 48 h. The rate of urea hydrolysis was more rapid at field capacity than at the 1:1 soil:water ratio. Urea hydrolysis was higher in sesbaniatreated soils, followed by cowpea, poultry manure, farmyard manure, rice straw and wheat straw at both the moisture levels. At field capacity, 85.5% urea was hydrolysed in sesbania-treated soil as compared to 32% in untreated soil after 24 hours of incubation, while at the 1:1 soil:water ratio the corresponding values were 81.5 and 27.5%. Urea hydrolysis followed first order reaction kinetics at both the moisture levels.
Residual effect of leguminous crops and inorganic fertilizer on soil properties and maize grain yield
Authors: Asibuo J. , Safo E. , Asafo-Adjei B. , Osei-Bonsu P.
Published: September 2008

Soil management practices that utilize organic matter have great potential to increase productivity in sub-Saharan Africa. Field studies were carried out between September 1995 and August 1998 to determine the effects of three leguminous crop species: velvet bean (
Mucuna pruriens
var.
utilis
), groundnut (
Arachis hypogaea
L.) and cowpea (
Vigna unguiculata
(L.) Walp), and inorganic fertilizer on the soil properties and succeeding maize grain yield when grown in rotation on a sandy soil classified as Haplic Lixisol in the forest-savannah transition zone of Ghana. The legumes were established in the minor seasons and maize in all the plots in the major cropping seasons. A 2 × 3 factorial design laid out in a randomized complete block was used. The main plots consisted of three leguminous crop residues and the sub-plots of two fertilizer levels (0 and 45 kg N ha
−1
, 19 kg P ha
−1
, 19 kg K ha
−1
). The control consisted of maize following maize with the recommended fertilizer rate (90 kg N ha
−1
, 37 kg P ha
−1
, 37 kg K ha
−1
). On average the
Mucuna
plots added 4.0 t ha
−1
of crop residue to the soil in a season and cowpea 1.0 t ha
−1
. The preceding crops had little effect on the soil properties. Leaf area index, total dry matter and maize grain yields were significantly affected by fertilizer. The best maize grain yield (6787 kg ha
−1
) was recorded in the first year on
Mucuna
plots with half the recommended rate of fertilizer. The cropping sequence with
Mucuna
residue was the most efficient. The gap in maize grain yield between the fertilized and unfertilized treatments widened each successive year. The interaction between organic matter and fertilizer may have been limited due to the surface application of the organic residue.
Impact of improved fallow periods on soil properties and productivity of maize ( Zea mays L.) in major and minor seasons of Asian humid tropics
Authors: Sangakkara U. , Stamp P.
Published: September 2008

Improved fallows are considered an easy, low cost and suitable method of increasing the productivity and sustainability of smallholder tropical rainfed cropping systems, although most farmers allow weeds to grow when the environmental conditions are not conductive for crop production. Field studies were carried out over the minor and major seasons, to evaluate the impact of a preceding improved fallow using
Crotalaria
or
Tithonia
, two popular tropical green manures, on selected soil properties, and on the growth and yield of maize. Improved fallows enhanced chemical soil properties significantly and the impact was most prominent at the onset of the minor maize season. Thus, the growth and yield of maize was also increased to a greater extent in this season, when yields are generally lower due to the suboptimal climatic conditions of lower rainfall and higher temperatures. However, fallows in the minor season also improved soil characteristics and maize yields in the major season, the most significant impact being increased seed yields and harvest indices. Although farmers may not grow fallow crops in major seasons, the potential of these green manure fallows in increasing maize yields in minor seasons and possible strategies to include the fallows in the cropping sequences of tropical rainfed upland cropping systems are discussed on the basis of this field study.
Studies on the drought and heat stress response of green bean ( Phaseolus vulgaris L.) varieties under phytotronic conditions
Authors: Nemeskéri E. , Remenyik J. , Fári M.
Published: September 2008

The drought tolerance of six green-and yellow-podded varieties of green beans with different genetic backgrounds was tested in the phytotron. During the week prior to flowering the plants were kept either at 25/15°C (day/night) or at high temperature (30/15°C), with RH 75% and optimum water supplies. The heat-stressed plants were then divided into three groups; the first was returned to the control (25/15°C) chamber (RH 75%, optimum water supplies), while the second and third were exposed to mild drought stress (RH 60%, 50% water) at temperatures of 30/15°C and 35/25°C, respectively, throughout the flowering period.The varieties survived the short period of heat stress (30/15°C) prior to flowering without damage provided the temperature during flowering was reduced to 25/15°C and the water supplies were optimum. There was a sharp increase in the carotene level in the leaves of drought-stressed plants when the temperature during flowering was 30/15°C, but in plants exposed to 35/25°C during flowering the level dropped to near the control level. The latter group exhibited considerable damage, with a reduction in the water-soluble antioxidant content (ACW: antioxidant capacity of water-soluble substances) and the chlorophyll
b
content compared with the control.The antioxidant content (ACW) in the dark green leaves of green-podded varieties was lower than in the yellow-podded varieties and did not change as the result of drought and heat stress. In yellow-podded varieties, however, there was a significant decline in ACW in response to stress. Differences between the varieties in their adaptability to drought and heat could be detected as changes in the chlorophyll and carotene contents of the leaves even at 30/15°C.
Effect of drought damage in vine varieties
Authors: Mikóczy N.
Published: September 2008

Drought stress caused substantial damage to the certified vineyard examined in Szomód, Hungary, in 2004. The varieties included in the experiment were Chardonnay, Sauvignon Blanc, Királyleányka, Pinot Noir and Kékfrankos. Drought caused the greatest deterioration in yield quantity and quality in the varieties Kékfrankos and Királyleányka. The yield was 66% lower and the quality 3 MM° (Hungarian must degrees) lower than that recorded on the control area, which was less severely affected by the drought. In the case of Pinot Noir the soil water-holding capacity (WHC%) was below the critical 15% value, again leading to a decline in yield quantity and sugar concentration, though the difference compared with the control was not as great as for the two former varieties. Although the yield of Chardonnay decreased slightly, the quality improved. This could probably be attributed to the similarly low soil WHC% in the control and drought-struck areas.All in all it could be concluded that all the vine varieties exhibited stress symptoms at a soil WHC of below 30%. The varieties could be divided into three groups on the basis of stress sensitivity, with Királyeányka and Kékfrankos in the most susceptible group, Chardonnay in the moderately susceptible group, and Pinot Noir and Sauvignon Blanc intermediate between the two.
Some comments on reforming the system of health insurance in Hungary
Authors: Kornai J.
Published: September 2008

Transforming the system of health insurance was on the reform agenda of the Hungarian government in 2007. Two alternative approaches were presented: to maintain the old state-owned single-payer scheme, or to introduce a multi-payer scheme based on the competition of private insurance companies. Finally a compromise was accepted. According to the draft legislation several insurance companies would enter, each of them based on a blend of public and private ownership.The paper presents a critique of this compromise scheme, discussing the advantages and shortcomings of various alternative approaches. It argues against mechanical, universal and too rapid changes, and advocates caution, experimentation and gradual changes.In spite of the warnings the law on health insurance reform was first accepted by the Hungarian Parliament, and then, a few months later, it was withdrawn.
Competitive and cooperative attitudes in the transforming economy of Hungary
Authors: Hámori B. , Szabó K. , Derecskei A. , Hurta H. , Tóth L.
Published: September 2008

The basic institutions and legal frames of a market economy were established quite quickly after the regime change in East-Central Europe, including Hungary. But there has been a much slower change in the behaviour of economic actors. The purpose of the research was to show the extent to which the competitive attitude and the cooperative behaviour both essential to market economies have developed in the nearly two decades since the regime change.* Are the actors in the economy capable of a positive response to the appearance of foreign competitors, or has the old, anti-competitive attitude still been prevailing? How is the behaviour of the competitors influenced by state intervention? The answers to these questions are based on 71 semi-structured interviews and on their comparison to the data of some international surveys. In the paper we were searching for links between the picture developing from the interviews and the age of the interviewees, the market position and the size of their firms.
Estimating the Hungarian New-Keynesian phillips curve
Authors: Menyhért B.
Published: September 2008

This paper estimates the hybrid New-Keynesian Phillips curve (NKPC) for Hungary with different techniques. Because of weak instruments, single-equation GMM estimations yield very unreliable results. More robust methods show that basically no statistical inference is possible as to the true specification of the inflation dynamics. However, a more efficient simultaneous-equations method, the full information maximum likelihood (FIML) estimator provides identified parameters. Furthermore, coefficient estimates on the driving variable are positive and significant for the first time, lending much-needed empirical support in favour of the New-Keynesian model. Inflation appears to be determined to an equal extent by past inflation and forward-looking expectations. Structural analysis yields realistic estimates for the frequency of price adjustments and suggests that the dominant price setting behaviour is backward-looking.
Packing a triangle with positive homothetical copies
Authors: Lassak Marek , Ściesińska Joanna
Published: September 2008

We consider packing a triangle with a number of equal positive homothetical copies. In particular, we show that every triangle can be packed with 7 copies of ratio \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tfrac{2}{7}$$
\end{document}, with 8 copies of ratio \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tfrac{3}{{11}}$$
\end{document}, and with 9 and 10 copies of ratio \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tfrac{1}{4}$$
\end{document}. All these ratios cannot be enlarged. We also present hypothetically best packings by greater number of copies.
King Tubby meets the Upsetter at the grass roots of dub
Authors: Partridge Christopher
Published: September 2008

There can be few aficionados of electronic dance music who have not come across the term ‘dub’. Its ubiquity within contemporary dance cultures is conspicuous. However, its roots lie not in contemporary dance music per se, nor within Anglo-American, white, middle-class cultures, but within the ska and reggae sound system culture that emerged in Jamaica in the 1960s. ‘Dub’ refers to a process of deconstruction, by which the engineer strips music down to its basic rhythm components, introduces novel elements, and thereby provides a new interpretation of the material. While such processes are very common within contemporary electronic music, their origins are not well known and often misunderstood. Focusing on the work of King Tubby and Lee Perry, this article maps the emergence of dub and, in so doing, both indicates its wider significance and posits a particular understanding of its genesis. Whilst it is recognized that the early history of dub is complex, being the result of a confluence of various streams of Jamaican musical creativity, and whilst key figures such as Joe Gibbs, Errol Thompson, Sylvan Morris, and Augustus Pablo need to be discussed in any comprehensive account, the article argues that its genesis can be traced to one engineer in particular, King Tubby.
Human T-Cell Lymphotropic Virus Type 1 Infection of CD34+ Hematopoietic Progenitor Cells Induces Cell Cycle Arrest by Modulation of p21cip1/waf1 and Survivin
Authors: Banerjee Prabal , Sieburg Michelle , Samuelson Elizabeth , Feuer Gerold
Published: September 2008

Human T-cell lymphotropic virus type 1 (HTLV-1) is an oncogenic retrovirus and the etiologic agent of adult T-cell leukemia (ATL), an aggressive CD4+ malignancy. HTLV-2 is highly homologous to HTLV-1; however, infection with HTLV-2 has not been associated with lymphoproliferative diseases. Although HTLV-1 infection of CD4+ lymphocytes induces cellular replication and transformation, infection of CD34+ human hematopoietic progenitor cells (HPCs) strikingly results in G0/G1 cell cycle arrest and suppression of in vitro clonogenic colony formation by induction of expression of the cdk inhibitor p21cip1/waf1 (p21) and concurrent repression of survivin. Immature CD34+/CD38− hematopoietic stem cells (HSCs) were more susceptible to alterations of p21 and survivin expression as a result of HTLV-1 infection, in contrast to more mature CD34+/CD38+ HPCs. Knockdown of p21 expression in HTLV-1-infected CD34+ HPCs partially abrogated cell cycle arrest. Notably, HTLV-2, an HTLV strain that is not associated with leukemogenesis, does not significantly modulate p21 and survivin expression and does not suppress hematopoiesis from CD34+ HPCs in vitro. We speculate that the remarkable differences in the activities displayed by CD34+ HPCs following infection with HTLV-1 or HTLV-2 suggest that HTLV-1 uniquely exploits cell cycle arrest mechanisms to establish a latent infection in hematopoietic progenitor/hematopoietic stem cells and initiates preleukemic events in these cells, which eventually results in the manifestation of ATL.

Disclosure of potential conflicts of interest is found at the end of this article.
Endogenous Matrix Metalloproteinase (MMP)-3 and MMP-9 Promote the Differentiation and Migration of Adult Neural Progenitor Cells in Response to Chemokines
Authors: Barkho Basam Z. , Munoz Ari E. , Li Xuekun , Li Lu , Cunningham Lee Anna , Zhao Xinyu
Published: September 2008

Adult neurogenesis is regulated by both intrinsic programs and extrinsic stimuli. The enhanced proliferation of adult neural stem/progenitor cells (aNPCs) in the subventricular zone and the migration of neuroblasts toward the ischemic region in adult brains present a unique challenge as well as an opportunity to understand the molecular mechanisms underlying the extrinsic cue-induced neurogenic responses. Matrix metalloproteinases (MMPs) are a family of proteinases known to play a role in extracellular matrix remodeling and cell migration. However, their presence in aNPCs and their potential function in injury-induced aNPC migration remain largely unexplored. Here we demonstrate that in response to two injury-induced chemokines, stromal cell-derived factor 1 (SDF-1) and vascular endothelial growth factor, aNPCs differentiated into migratory cells that expressed increased levels of MMP-3 and MMP-9. Whereas differentiated neuroblasts and a subpopulation of astrocytes migrated toward the chemokines, undifferentiated progenitors did not migrate. Blocking the expression of MMP-3 or MMP-9 in aNPCs interfered with both the differentiation of aNPCs and chemokine-induced cell migration. Thus, endogenous MMPs expressed by aNPCs are important for mediating their neurogenic response to extrinsic signals.

Disclosure of potential conflicts of interest is found at the end of this article.
TRIB3 is implicated in glucotoxicity- and oestrogen receptor-stress-induced β-cell apoptosis
Authors: Qian Bo , Wang Haiyan , Men Xiuli , Zhang Wenjian , Cai Hanqing , Xu Shiqing , Xu Yaping , Ye Liya , Wollheim Claes B , Lou Jinning
Published: September 2008

We found that TRIB3, an endogenous inhibitor of Akt (PKB), is expressed in pancreatic β-cells. The TRIB3 expression is significantly increased in islets isolated from hyperglycemic Goto–Kakizaki rats compared with normal glycemic controls. In vitro high glucose treatment also resulted in increased TRIB3 expression in rat INS1 cells. To investigate the role of TRIB3 in the regulation of β-cell function, we established an INS1 stable cell line allowing inducible expression of TRIB3. We demonstrated that overexpression of TRIB3 mimicked the glucotoxic effects on insulin secretion and cell growth in INS1 cells. Moreover, induction of TRIB3 also synergistically enhanced high-glucose-elicited apoptosis in INS1 cells, whereas siRNA knock-down of TRIB3 showed the opposite effects. We also confirmed that the ΔΨm of mitochondria was decreased, caspase-3 activity was up-regulated and reactive oxygen species content was increased in TRIB3 overexpressing β cells in high glucose condition. Most interestingly, the oestrogen receptor (ER) stress inducer, thapsigargin, mimicked the high glucose effects on up-regulation of TRIB3 and generation of apoptosis in cultured INS1 cells. These effects were specifically prevented by siRNA knock down of TRIB3. We therefore conclude that TRIB3 is implicated in glucotoxicity- and ER stress-induced β-cell failure. TRIB3 could be a potential pharmacological target for prevention and treatment of type 2 diabetes.
Controlling and increasing the inherent voltage in cement paste
Authors: Huang C.-Y. , Chung D.D.L.
Published: September 2008

An inherent voltage occurs in cement paste, making the material an electret. Both poling (up to 225 V/m DC, causing long-range ion movement) during the 24 h setting and the use of sodium silicate liquid (which provides Na+ ions) as an admixture were found to increase the inherent voltage, in addition to making the voltage more stable and better controlled. Without poling and sodium silicate, the inherent voltage after curing varied in sign and magnitude in an uncontrolled fashion among specimens poured from the same mix; for the same specimen, it varied significantly with the curing time and asystematically during the first 10 days of curing and stabilised thereafter. With both sodium silicate and poling, the voltage was positive (same polarity as the poling voltage), decreased with time throughout curing, and levelled off at a voltage that increased with increasing sodium silicate content, with the highest value attained in the present study being 0·35 V. The time constant for depoling during curing ranged from 2 to 7 days in the initial depoling period (up to 11 days), and ranged from 74 to 150 days in the subsequent period.
SEASONALITY OF WATER AND HEAT FLUXES OVER A TROPICAL FOREST IN EASTERN AMAZONIA
Authors: da Rocha Humberto R. , Goulden Michael L. , Miller Scott D. , Menton Mary C. , Pinto Leandro D. V. O. , de Freitas Helber C. , e Silva Figueira Adelaine M.
Published: September 2008

We used the eddy covariance technique from July 2000 to July 2001 to measure the fluxes of sensible heat, water vapor, and CO2 between an old‐growth tropical forest in eastern Amazonia and the atmosphere. Precipitation varied seasonally, with a wet season from mid‐December 2000 to July 2001 characterized by successive rainy days, wet soil, and, relative to the dry season, cooler temperatures, greater cloudiness, and reduced incoming solar and net radiation. Average evapotranspiration decreased from 3.96 ± 0.65 mm/d during the dry season to 3.18 ± 0.76 mm/d during the wet season, in parallel with decreasing radiation and decreasing water vapor deficit. The average Bowen ratio was 0.17 ± 0.10, indicating that most of the incoming radiation was used for evaporation. The Bowen ratio was relatively low during the early wet season (December–March), as a result of increased evaporative fraction and reduced sensible heat flux. The seasonal decline in Bowen ratio and increase in evaporative fraction coincided with an increase in ecosystem CO2 assimilation capacity, which we attribute to the growth of new leaves. The evaporative fraction did not decline as the dry season progressed, implying that the forest did not become drought stressed. The roots extracted water throughout the top 250 cm of soil, and water redistribution, possibly by hydraulic lift, partially recharged the shallow soil during dry season nights. The lack of drought stress during the dry season was likely a consequence of deep rooting, and possibly vertical water movement, which allowed the trees to maintain access to soil water year round.
Managing for ocean biodiversity to sustain marine ecosystem services
Authors: Palumbi Stephen R , Sandifer Paul A , Allan J David , Beck Michael W , Fautin Daphne G , Fogarty Michael J , Halpern Benjamin S , Incze Lewis S , Leong Jo-Ann , Norse Elliott , Stachowicz John J , Wall Diana H
Published: September 2008

Managing a complex ecosystem to balance delivery of all of its services is at the heart of ecosystem‐based management. But how can this balance be accomplished amidst the conflicting demands of stakeholders, managers, and policy makers? In marine ecosystems, several common ecological mechanisms link biodiversity to ecosystem functioning and to a complex of essential services. As a result, the effects of preserving diversity can be broadly beneficial to a wide spectrum of important ecosystem processes and services, including fisheries, water quality, recreation, and shoreline protection. A management system that conserves diversity will help to accrue more “ecoservice capital” for human use and will maintain a hedge against unanticipated ecosystem changes from natural or anthropogenic causes. Although maintenance of biodiversity cannot be the only goal for ecosystem‐based management, it could provide a common currency for evaluating the impacts of different human activities on ecosystem functioning and can act as a critical indicator of ecosystem status.
Twenty years of zebra mussels: lessons from the mollusk that made headlines
Authors: Strayer David L
Published: September 2008

In the 20 years since zebra mussels (Dreissena polymorpha) first appeared in North America, they have become one of our most widespread and abundant freshwater animals, and have fundamentally transformed freshwater food webs and biogeochemistry. Indeed, few human impacts on North American fresh waters have been greater or more far‐reaching than the arrival of this single species. Nevertheless, ecological research has been uneven, and important research questions remain unanswered, especially concerning the long‐term, large‐scale effects of the invasion. Economic impacts have also been incompletely estimated, although they already exceed $100 million. We know little about the extent to which large outreach programs about zebra mussels have changed public knowledge, attitudes, or behaviors, and there are still substantial gaps in policies to curb the establishment, spread, and impacts of species like zebra mussels. Scientific, educational, and policy responses to the zebra mussel invasion highlight our successes and limitations concerning alien species in general.
Design and Production of Specifically High Affinity Reacting Peptides (SHARP®-s)
Authors: Biro Jan C.
Published: September 2008

Background:

A partially random target selection method was developed to design and produce affinity reagents
(target) to any protein query. It is based on the recent concept of Proteomic Code (for review see Biro, 2007 [1]) which
suggests that significant number of amino acids in specifically interacting proteins are coded by partially complementary
codons. It means that the 1 and 3 residues of codons coding many co-locating amino acids are complementary but the
2 may but not necessarily be complementary: like 5’-AXG-3’/3’-CXT-5’ codon pair, where X is any nucleotide.

Results:

A mixture of 45 residue long, reverse, partially complementary oligonucleotide sequences (target pool) was synthesized
to selected epitopes of query mRNA sequences. The 2nd codon residues were randomized. The target oligonucleotide
pool was inserted into vectors, expressed and the protein products were screened for affinity to the query in Bacterial
Two-Hybrid System. The best clones were used for larger-scale protein syntheses and characterization. It was possible
to design and produce specific high affinity reacting (Kd: ~100 nM) oligopeptide reagents to GAL4 query oligopeptides.

Conclusions:

Second codon residue randomization is a promising method to design and produce affinity peptides to any
protein sequences. The method has the potential to be a rapid, inexpensive, high throughput, non-immunoglobulin based
alternative to recent in vivo antibody generating procedures.
Microfluidic Micropillar Arrays for 3D Cell Culture
Authors: Kim Minseok S. , Hwang Hyundoo , Choi Youn-Suk , Park Je-Kyun
Published: September 2008

Cell-based assays are one of the most important steps to select huge amount of drug candidates in drug discovery.
To get more credible assay results, cell culture in the form of microscale environment and three-dimension has been
exploited by microfluidic hydrodynamic focusing. However, the method still needs an enhanced reliability of scaffold
formation and fast cell immobilization in a microchannel. In this report, we fabricated a microfluidic micropillar arrays
(MMA) platform for cell culture using a poly(dimethylsiloxane) (PDMS) replica molding process. Peptide hydrogel and
Matrigel were nicely patterned along the micropillars by surface tension. In addition, a linear concentration gradient profile
was presented in a stripe-shaped Matrigel matrix and the simulation result with computational fluid dynamics (CFD)
solver was corresponded to the experimental profile. The MMA platform was successfully applied to the hepatocellular
carcinoma cell (HepG2) culture for 2 days.
Plasma Assisted Decontamination of Bacterial Spores
Authors: Kuo Spencer P
Published: September 2008

The efficacy and mechanism of killing bacterial spores by a plasma torch is studied. Bacterial-spore (Bacillus cereus) suspension is inoculated onto glass/paper slide-coupons and desiccated into dry samples, and inoculated into well-microplate as wet sample. The exposure distance of all samples is 4 cm from the nozzle of the torch. In the experiment, paper slide-coupon is inserted inside an envelope. The kill times on spores in three types of samples are measured to be about 3, 9, and 24 seconds. The changes in the morphology and shape of still viable spores in treated wet samples are recorded by scanning electron and atomic force microscopes. The loss of appendages and exosporium in the structure and squashed/flattened cell shape are observed. The emission spectroscopy of the torch indicates that the plasma effluent carries abundant reactive atomic oxygen, which is responsible for the destruction of spores.
Interaction Between Engineering, Science and Art
Authors: Tamir Abraham
Published: September 2008

This article is the beginning of a new section entitled Engineering and Science by Art where the emphasis will
be on Chemical Engineering. It applies to an approach developed by the author where subjects related to engineering and sciences are demonstrated by artworks. This makes the subjects more understandable and easy to percept. After studying
the articles written by the author, he believes that in the future the readers will also be able to write articles of this type.
Antioxidant Activity of a Cissus verticillata Fraction and Tyramine, its Bioactive Constituent, on Alloxan-Induced Diabetic Rats
Authors: Lino Cleide de Sousa , Sales Thiago de Paiva , Alexandre Francisco S. Oliveira , Ferreira Jamile M. , Sousa Daniel Freire de , Gomes Patrícia Bezerra , Amaral Jeferson Falcão do , Maia Flávio D. , Silveira Edilberto R. , Queiroz Maria Goreti Rodrigues de , Sousa Francisca Cléa Florenço de , Viana Glauce Socorro de Barros
Published: September 2008

In the present study, the antioxidant activity of a methanol soluble fraction (MSF) from Cissus verticillata, used
in Brazil and elsewhere as a hypoglycemic and antidiabetic medicinal plant, and tyramine (TYR), one of its main bioactive
constituents, was assessed. For this, male Wistar rats were submitted to alloxan injection (40 mg/kg, i.v.) in order to
induce a diabetic state and, 48 h later, glycemia was determined. Animals were distributed into groups: normal controls
(NC); diabetic controls (DC); DC plus MSF; and DC plus TYR. Another group was treated with glibenclamide (GLI),
used as a positive control. After 5-day treatments, animals were sacrificed for liver dissection, and determination of antioxidant
markers such as thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), catalase and nitrite
concentrations. The antioxidant effect was also evaluated on the pentobarbital-induced sleeping time, before and after
CCl4 treatment. Under our experimental conditions, diabetic rats did not present any alteration in liver lipid peroxidation,
before (DC) or after treatments with the MSF; TYR or GLI, as compared to normal controls (NC). Levels of GSH were
significantly increased in 79% in DC, as related to NC, and the effects were partially reversed in diabetic rats, after MSF
treatments at the higher dose. However, while similar effects were observed after TYR and GLI, both drugs brought values
of GSH to normality. The DC group had increased liver catalase activity, as compared to NC, and these effects were
partially reversed by MSF and almost completely by TYR and GLI. Significant increases were also detected in nitrite
concentrations in livers of DC, as an index of free radical formation, and a large reduction was observed after MSF, TYR
and GLI treatments of diabetic rats, as compared to NC. MSF and TYR also prevented prolongation of the pentobarbitalinduced
sleeping time by CCl4, suggesting hepatoprotective and anti-oxidative effects. In conclusion, we showed that the
antioxidant activity probably plays an important role in the antidiabetic effect of C. verticillata, and TYR is at least in part
responsible for this property.
Mechanisms of Acute Cocaine Toxicity
Authors: Heard Kennon , Palmer Robert , Zahniser Nancy R.
Published: September 2008

Patients with acute cocaine poisoning present with life-threatening symptoms involving several organ systems.
While the effects of cocaine are myriad, they are the result of a limited number of cocaine-protein interactions, including
monoamine transporter, neurotransmitter receptor and voltage-gated ion channels. These primary interactions trigger a
cascade of events that ultimately produce the clinical effects. The purpose of this article is to review the primary interactions
of cocaine and the effects that these interactions trigger. We also describe the progression of symptoms observed in
cocaine poisoning as they relate to serum cocaine concentrations.
Lightning Channel-Base Current Identification as Solution of a Volterralike Integral Equation
Authors: Delfino Federico , Procopio Renato , Rossi Mansueto
Published: September 2008

In this paper, a novel procedure to reconstruct the lightning channel-base current starting from the measurement of the induction field generated by it is presented. The procedure is based on a suitable mathematical manipulation of the equation expressing the induction field in the time domain, in order to transform it into a Volterra-like integral equation. Such kind of equations can be easily numerically solved without resorting to any sort of regularization techniques as they are not affected by the typical ill-conditioning of the inverse problems. The developed algorithm has been validated by means of several numerical simulations, which have shown its effectiveness also in presence of measurement noise on the induction field values.
Emission Scenario Assessment of Gasohol Reformulation Proposals and Ethanol Use in the Metropolitan Area of São Paulo
Authors: Martins L.D. , Andrade M.F.
Published: September 2008

The frequent episodes of high concentrations of ozone and of inhalable particulate matter occurring in the Metropolitan Area of Sao Paulo (MASP) are primarily associated with vehicle emissions. The objective of this study was to evaluate the impact of the use of reformulations of the gasoline-ethanol blend known as gasohol and of ethanol on the ozone formation. A three-dimensional photochemical model was employed to estimate the sensitivity of ozone and evaluate the implementation of emission scenarios, considering various fuel formulations, in the MASP. The base case ozone concentrations were consistent with the observations over six air quality monitoring stations located in the MASP, suggesting that the model can be used to evaluate the impact that various emission scenarios would have on ozone levels. Six scenarios were analyzed; scenarios 1 to 5 involved reductions in compounds found in gasohol in various proportions compared with the base emission inventory and scenario 6 specified that the entire light duty fleet would burn pure ethanol. In scenario 3 (reductions in olefins, aromatics and benzene) and scenario 5 (reductions in the five species that are associated with higher ozone sensitivity), ozone concentrations were below the national standard only at the air quality monitoring stations (not domain-wide). Our results suggest that implementing scenario 6 would improve air quality in the MASP.