bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some physicochemical, microbiological, and sensory properties of tulum cheese produced from ewe's milk via a modified method
Authors: CEYLAN ZİYA GÖKALP , ÇAǦLAR ABDULLAH , ÇAKMAKÇI SONGÜL 
Published: July 2007

The purpose of this research was to investigate an alternative way to manufacture Erzincan tulum cheese in order to shorten production time and improve food safety. By adding 0.5% starter culture (Streptococcus salivarius ssp. thermophilus and Lactobacillus delbrueckii ssp. bulgaricus cultures at a 1 : 1 ratio) to pasteurized ewe's milk (65°C for 30 min), the required time for manufacturing Erzincan tulum cheese was shortened from the traditional 10–12 days to 2 days. The cheeses manufactured with the modified method were ripened in three different packaging materials: goatskin, plastic, and ceramic. Physicochemical, microbiological, and sensory properties of the Erzincan tulum cheese were obtained during the ripening period at intervals of 2, 30, 60, and 90 days, and compared with those properties of samples manufactured by the traditional method. Significant microbiological and physicochemical differences were found between the modified samples and the traditional samples (P < 0.01). However, the modified samples and the traditional samples were statistically similar in sensory properties to the exception of the modified sample packaged in plastic.
Flip-Flop of Fluorescently Labeled Phospholipids in Proteoliposomes Reconstituted with
Saccharomyces cerevisiae
Microsomal Proteins
Authors: Vehring Stefanie , Pakkiri Leroy , Schröer Adrien , Alder-Baerens Nele , Herrmann Andreas , Menon Anant K. , Pomorski Thomas 
Published: July 2007

ABSTRACT

A phospholipid flippase activity from the endoplasmic reticulum (ER) of the model organism
Saccharomyces cerevisiae
has been characterized and functionally reconstituted into proteoliposomes. Analysis of the transbilayer movement of acyl-7-nitrobenz-2-oxa-1,3-diazol-4-yl (acyl-NBD)-labeled phosphatidylcholine in yeast microsomes using a fluorescence stopped-flow back exchange assay revealed a rapid, ATP-independent flip-flop (half-time, <2 min). Proteoliposomes prepared from a Triton X-100 extract of yeast microsomal membranes were also capable of flipping NBD-labeled phospholipid analogues rapidly in an ATP-independent fashion. Flippase activity was sensitive to the protein modification reagents
N
-ethylmaleimide and diethylpyrocarbonate. Resolution of the Triton X-100 extract by velocity gradient centrifugation resulted in the identification of a ∼4S protein fraction enriched in flippase activity as well as of other fractions where flippase activity was depleted or undetectable. We estimate that flippase activity is due to a protein(s) representing ∼2% (wt/wt) of proteins in the Triton X-100 extract. These results indicate that specific proteins are required to facilitate ATP-independent phospholipid flip-flop in the ER and that their identification is feasible. The architecture of the ER protein translocon suggests that it could account for the flippase activity in the ER. We tested this hypothesis using microsomes prepared from a temperature-sensitive yeast mutant in which the major translocon component, Sec61p, was quantitatively depleted. We found that the protein translocon is not required for transbilayer movement of phospholipids across the ER. Our work defines yeast as a promising model system for future attempts to identify the ER phospholipid flippase and to test and purify candidate flippases.
Integration Site Selection by the
Bacteroides
Conjugative Transposon CTnBST
Authors: Song Bo , Shoemaker Nadja B. , Gardner Jeffrey F. , Salyers Abigail A. 
Published: July 2007

ABSTRACT

A newly discovered
Bacteroides
conjugative transposon (CTn), CTnBST, integrates more site specifically than two other well-studied CTns, the
Bacteroides
CTn CTnDOT and the enterococcal CTn Tn
916
. Moreover, the integrase of CTnBST, IntBST, had the C-terminal 6-amino-acid signature that is associated with the catalytic regions of members of the tyrosine recombinase family, most of which integrate site specifically. Also, in most of these integrases, all of the conserved amino acids are required for integration. In the case of IntBST, however, we found that changing three of the six conserved amino acids in the signature, one of which was the presumed catalytic tyrosine, resulted in a 1,000-fold decrease in integration frequency. Changes in the other amino acids had little or no effect. Thus, although the CTnBST integrase still seems to be a member of the tyrosine recombinase family, it clearly differs to some extent from other members of the family in its catalytic site. We also determined the sequence requirements for CTnBST integration in the 18-bp region where the crossover occurs preferentially during integration. We found that CTnBST integrates in this preferred site about one-half of the time but can also use other sites. A consensus sequence was tentatively derived by comparison of a few secondary sites: AATCTGNNAAAT. We report here that within the consensus region, no single base change affected the frequency of integration. However, 3 bp at one end of the consensus sequence (CTG) proved to be essential for integration into the preferred site. This sequence appeared to be at one end of a 7-bp crossover region, CTGNNAA. The other bases could vary without affecting either integration frequency or specificity. Thus, in contrast to well-studied site-specific recombinases which require homology throughout the crossover region, integration of CTnBST requires homology at one end of the crossover region but not at the other end.
Simultaneous Catabolite Repression between Glucose and Toluene Metabolism in
Pseudomonas putida
Is Channeled through Different Signaling Pathways
Authors: del Castillo Teresa , Ramos Juan L. 
Published: July 2007

ABSTRACT

Pseudomonas putida
KT2440(pWW0) can use toluene via the TOL plasmid-encoded catabolic pathways and can use glucose via a series of three peripheral chromosome-encoded routes that convert glucose into 6-phosphogluconate (6PG), namely, the glucokinase pathway, in which glucose is transformed to 6PG through the action of glucokinase and glucose-6-phosphate dehydrogenase. Alternatively, glucose can be oxidized to gluconate, which can be phosphorylated by gluconokinase to 6PG or oxidized to 2-ketogluconate, which, in turn, is converted into 6PG. Our results show that KT2440 metabolizes glucose and toluene simultaneously, as revealed by net flux analysis of [
13
C]glucose. Determination of glucokinase and gluconokinase activities in glucose metabolism, gene expression assays using a fusion of the promoter of the Pu TOL upper pathway to ′
lacZ
, and global transcriptomic assays revealed simultaneous catabolite repression in the use of these two carbon sources. The effect of toluene on glucose metabolism was directed to the glucokinase branch and did not affect gluconate metabolism. Catabolite repression of the glucokinase pathway and the TOL pathway was triggered by two different catabolite repression systems. Expression from Pu was repressed mainly via PtsN in response to high levels of 2-dehydro-3-deoxygluconate-6-phosphate, whereas repression of the glucokinase pathway was channeled through Crc.
An Existential-Dialectical-Phenomenological Approach to Understanding Cultural Tilts: Implications for Multicultural Research and Practice
Authors: Hannush Mufid James 
Published: July 2007

AbstractAn existential-dialectical-phenomenological approach is applied to the understanding of the universal tensions between multicultural and transcultural value-laden modalities of existence. Differences in cultural comportments are described as variations in local human ways in dealing with universal and bipolar existential modalities, values, or needs, such as freedom versus limitation, independence versus (inter)dependence, and connectedness versus separateness. Cultures are described as being organized around and as providing their members with ways of dealing with these value-laden dialectical dilemmas. Cultures are further depicted as legitimating one dialectical pole to the detriment of the other dialectical pole. Some cultures, for example, legitimate the dialectical poles of freedom, independence, and separateness, while deemphasizing or denying the dialectical poles of limitation, (inter)dependence, and connectedness. Other cultures legitimate the opposite. These one-sided value orientations of cultures are referred to as cultural tilts. The implications for the practice of multicultural counseling and phenomenologically-based qualitative research are delineated.
The Multitude and the Kangaroo: A Critique of Hardt and Negri's Theory of Immaterial Labour
Authors: Camfield David 
Published: July 2007

AbstractHardt and Negri's theory of immaterial labour provides a socio-economic foundation in the contemporary world for the philosophical and political elements of their thought. Although there has been considerable engagement with Hardt and Negri's work, the socio-economic dimension of their thought has received little sustained attention. This is certainly true of their theory of immaterial labour. This article aims to remedy this oversight. It presents and scrutinises Hardt and Negri's concept of immaterial labour and its putative hegemony. It then examines the depiction of the world of paid work in advanced capitalist societies with which the theory is associated and looks at three alleged consequences of the rise of immaterial labour. It concludes that this dimension of Hardt and Negri's thought is profoundly flawed, that immaterial labour cannot play the role they wish to assign it in their theory, and that this failure suggests the importance of a different method of developing theory from that employed by Hardt and Negri, along with so many other contemporary writers.
Induction of P-glycoprotein expression and activity by ritonavir in bovine brain microvessel endothelial cells
Authors: Perloff Michael D , von Moltke Lisa L , Fahey Jeanne M , Greenblatt David J 
Published: July 2007

AbstractExtended treatment with human immunodeficiency virus (HIV) protease inhibitors (HPIs) is standard in HIV/AIDS therapy. While these drugs have helped decrease the overall incidence of AIDS defining illnesses, the relative prevalence of HIV/AIDS dementia has increased. HPIs may cause induction of blood-brain barrier (BBB) drug transporters (P-glycoprotein; P-gp) and thereby limit entry of HPIs into brain tissue, increasing the probability that the brain could become an HIV sanctuary site. Using bovine brain microvessel endothelial cells (BMEC) as an in-vitro model of the BBB, the potential for the HIV protease inhibitor ritonavir to cause induction of P-gp activity and expression was examined. BMEC were isolated from fresh cow brain by enzymatic digest and density centrifugation. Primary culture BMEC were co-incubated with ritonavir or vehicle control for 120 h. Quantitative drug accumulation of rhodamine 123 (Rh123) and fluorescence microscopy were used as measures of P-gp activity. P-gp expression was assessed using quantitative Western blotting. Ritonavir decreased Rh123 cell accumulation and increased P-gp immunoreactive protein in a concentration-dependent manner. Fluorescent microscopy mirrored Rh123 quantitative studies. In BMEC pretreated with 30 μM ritonavir, Rh123 accumulation was decreased 40% and immunoreactive P-gp protein increased 2-fold. Collectively, a strong correlation between decreased Rh123 BMEC accumulation and increased P-gp immunoreactive protein was observed (Spearman r2 = 0.77, P &lt; 0.0001). Thus extended exposure of BMEC to ritonavir caused a concentration-dependent increase in P-gp activity and expression. Similar findings may occur at the clinical level with prolonged HIV protease inhibitor use, giving insight into the central nervous system as an HIV sanctuary site and eventual development of HIV dementia.
Protective effect of total flavonoids fromBidens bipinnataL. against carbon tetrachloride-induced liver injury in mice
Authors: Zhong Ming-mei , Chen Fei-hu , Yuan Li-ping , Wang Xiao-hua , Wu Fan-rong , Yuan Feng-lai , Cheng Wen-ming 
Published: July 2007

AbstractBidens bipinnata L. is well known in China as a traditional Chinese medicine. This study was designed to evaluate the hepatoprotective activity of the total flavonoids of B. bipinnata L. (TFB) against carbon tetrachloride (CCI4)-induced acute liver injury in mice and to determine its mechanism of action. Oral administration of TFB at doses of 50, 100 and 200 mg kg−1 for 7 days significantly reduced the elevated relative values of liver weight, serum transaminases (alanine aminotransferase and aspartate aminotransferase) and the hepatic morphologic changes induced by CCl4 in mice. In addition, TFB markedly inhibited CCl4-induced lipid peroxidation and enhanced the activity of the antioxidant enzymes superoxide dismutase and glutathione peroxidase. Moreover, pretreatment with TFB suppressed nitric oxide production and nuclear factor-kB activation in CCl4-treated mice. The results suggest that TFB has significant hepatoprotective activity and its mechanism is related, at least in part, to its antioxidant properties. Further research is required to investigate the detailed mechanism of the protective effect of TFB on acute liver injury.
Sphingosine 1-phosphate (S1P) induces shape change in rat C6 glioma cells through the S1P2 receptor: development of an agonist for S1P receptors
Authors: Kim Kyeok , Kim Yu-Lee , Sacket Santosh J , Kim Hyo-Lim , Han Mijin , Park Deok Seong , Lee Baeck Kyoung , Lee Won Koo , Ha Hyun-Joon , Im Dong-Soon 
Published: July 2007

AbstractTreatment with isoprenaline led to a change in the cell morphology of rat C6 glioma cells. This morphological change was reverted by the addition of sphingosine 1-phosphate (S1P). Using this morphological change as a response marker we determined that DS-SG-44 ((2S,3R)-2-amino-3-hydroxy-4-(4-octylphenyl)butyl phosphoric acid) was an agonist of S1P receptors. The DS-SG-44-induced morphological reversion was not observed with such structurally related molecules as DS-SG-45 ((2S,3R)-2-amino-3-hydroxy-4-(3-octylphenyl)butyl phosphoric acid) and DS-SG-12 ((2S,3R)-2-amino-4-(4-octylphenyl)butane-1,3-diol). The S1P- and DS-SG-44-induced shape changes were nseither reproduced with the S1P1/S1P3 receptor agonist VPC24191 nor inhibited by the S1P1/S1P3 receptor antagonist, VPC23019. Transfection with small interfering RNA (siRNA) for the S1P2 receptor greatly inhibited the DS-SG-44-induced shape change, and in part an S1P-induced response. In the presence of VPC23019, siRNA transfection for the S1P2 receptor almost completely blocked the S1P- and DS-SG-44-induced shape changes. Our results suggested that DS-SG-44, a newly-synthesized S1P analogue, acted as an S1P receptor agonist and that the S1P-induced shape change in rat C6 glioma cells was mediated mainly through the S1P2 receptor, and cooperatively through the S1P1/S1P3 receptors.
Free bending characteristics of sheathed spiral strands under cyclic loading
Authors: Raoof M , Huang Y P 
Published: July 2007

A theoretical insight is given into the non-linear free bending characteristics of axially preloaded and large diameter sheathed spiral strands experiencing high external hydrostatic pressure in, for example, deep water floating platform applications. The theoretical model takes geometrical non-linearities and interwire friction fully into account. It is capable of estimating variations of strand plane-section bending stiffness, ( EI)eff, and hysteresis as a function of the imposed radius of curvature, magnitude of the external pressure, and level of mean axial load. An oversight in a previously reported analytical model for following the reductions in strand flexural rigidity due to interlayer slippage has also been identified and subsequently corrected. In addition, the corrected model (which assumed small deflections) has been extended to cover geometrical non-linearities due to changes in lay angle and helix radius. Numerical results are presented for a large diameter (102 mm OD) sheathed spiral strand experiencing various levels of mean axial load and external pressure. In particular, it is shown that under the plane-section bending assumption, the upper and lower bounds to ( EI)eff are, for all practical purposes, independent of the magnitude of mean axial load and external pressure. Moreover, the maximum possible values of radii of curvature associated with which plane-section bending is possible, have been identified in all cases. It is believed that even in the presence of interlayer slippage, the damping model (which is based on plane-section bending) offers reasonable and useful lower bounds to a strand's specific damping which should prove of value in certain applications involving cable dynamics.
Weight functions for curved crack fronts using bem
Authors: Bains R , Aliabadi M H , Rooke D P 
Published: July 2007

This paper presents an efficient numerical weight function technique, based on the boundary element method, for the determination of stress intensity factors of curved crack fronts in three-dimensional finite bodies. The weight functions are based on the notion of fundamental fields, which are defined from point loads acting at the crack front. A regularization procedure that incorporates the fundamental fields of the penny-shaped crack in an infinite elastic body is used to obtain weight functions for a penny-shaped edge crack in a cylindrical bar. Stress intensity factors for elliptical crack fronts can be generated by employing the properties of the fundamental fields at the load points on the crack front. Stress intensity factor variations along the crack-fronts are presented when these finite cracked geometries are subjected to various loads that produce mode I deformation of the crack faces. Wherever possible, solutions are compared with values published in the literature and are found to be in good agreement.
The use of model materials to simulate creep behaviour
Authors: Fessler H , Hyde T H 
Published: July 2007

The objective of this paper is to show that there are model materials which can be used to develop better assumption to improve theories, to verify the applicability of theories, or to get creep information which is otherwise unobtainable. The mechanical properties necessary to characterize non-linear component behaviour are defined and presented for some chill-cast lead alloys at 20°C. When normalized, they are shown to be sufficiently similar to structural steels to allow the prediction of prototype response from model tests. This paper also describes the methods used to make lead alloy models for the experimental study of creep of components.
An analysis of the symmetric rolling of aluminium strips using a three-dimensional elastic—plastic large deformation finite element method
Authors: Lin Z C , Huang C J 
Published: July 2007

This study focuses on the deformation which occurs in three-dimensional elastic-plastic aluminium strips when they undergo symmetric rolling with a rigid body roller. This research is based on the theory of large deformation and large strain, using the updated Lagrangian formulation (ULF) and the incremental method to develop the analysis model of the three-dimensional elastic-plastic characteristic of aluminium strip rolling. As for the determination of the direction of tangential friction force, this study also develops a modification algorithm to adjust to the three-dimensional rolling process. In addition, another rule is devised to identify the neutral point in order to further develop the theoretical model and computer program for the large deformation finite element method with the two-order strain rate equation. Finally, this study uses the numerical analysis model developed in this research to simulate the deformation which occurs in aluminium strips when they undergo symmetric rolling, and the variation of rolling force. The research also compares the average rolling force of simulated cold rolling with experimental results. The results verify that the author's model is acceptable.
Local government structure as a spatial framework for rural development in Nigeria
Authors: Akpan Philip A. 
Published: July 2007

AbstractRural development has attracted attention from many quarters. The present administration in Nigeria is particularly anxious to bring it about in the shortest time possible. But most of the discussions of rural development tend to neglect the vital link between it and administrative structure. This paper therefore stresses the role which an appropriate administrative arrangement can play in bringing about rural development. The paper reviews the various efforts that Nigeria has made since 1950 to derive a suitable local administrative structure. It focuses on the 1976 reform and shows how it has failed to provide a suitable spatial framework for rural development. Based on the experiences of the past and the realities of the present, some principles are put forward as guidelines for an effective local administrative structure. Finally, an administrative arrangement which is development oriented and comprehensive enough to cater for the interest of all communities is proposed.
State intervention, contradictions and agricultural stagnation in Tanzanian—Cashew nut vs charcoal production
Authors: Nindi B. C. 
Published: July 2007

AbstractThe article first describes Tanzanian development ideology and main economic activities. It explains economic decline and gives a brief description of Rufiji District. The next section examines the dynamics of state‐peasant‐commercial class relationship in Rufiji district within the wider context. There is a number of broad theoretical lines of reasoning that have come to predominate in contemporary debate on the origins and genesis of the African agricultural crisis and Tanzania in particular. This paper seeks to show that the notion of crisis must be subject to a careful, specific, and historically sensitive analysis.
Urban local government finance in Nigeria: The case of Onitsha local government
Authors: Olowu Dele 
Published: July 2007

AbstractOnitsha, located along the route that connects south‐western and south‐eastern Nigeria, has a very financially dynamic local government. Over one‐quarter of the total revenues of this local government come from its market and motor parks. This is an unusual source for a local government that has perhaps the largest per capita revenue in Nigeria—almost N40, compared with the national average of N4.9. The procedure for collecting this revenue is regarded as highly successful since there is greater reliance on the citizens than tax officials. The volume of revenues collected has allowed the council maintain a large surplus revenue over a long period of time, which enables it to carry out important programmes of primary and adult education. It is also beginning to develop its property revenue collection system in collaboration with the Anambra State government.
Small town local government finance in Kenya: The case of Karatina Town Council
Authors: Smoke Paul 
Published: July 2007

AbstractIn a country where local governments are plagued by numerous problems and are under frequent attack from national politicians and the central government, Karatina Town Council stands out as one of the few local authorities widely considered to be doing a highly effective job. This paper reviews the organization and functions of Kenyan local authorities and highlights major constraints on their performance. Some background information on Karatina Town Council is presented, followed by documentation of the council's superior performance and an analysis of the factors that seem to contribute to Karatina's success.