bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adult Education in Tanzania
Authors: Heisel Marsel A. 
Published: March 2008

Since the Arusha Declaration in 1967, Adult Education in Tanzania has become a major instrument in national development. Programs in literacy, health care and hygiene, and in the acquisition of technical competence have been parti cularly successful because adult education has been approached as an intrinsic and meaningful part of the learner's life. The purpose of education has changed from the learning of skills to the learn ing of self-reliance and the improvement of life in both individual and national levels. For example, in the teaching of literacy, attention is focused on subjects such as health, agricultural techniques, or political responsibilities and literacy is included in response to demand as the learners become aware of its functional importance. This paper critically reviews various adult education programs in Tanzania, particularly focusing on "Literacy for Working" and radio programs with discussion groups.
Molecular evolution of dimeric α-amylase inhibitor genes in wild emmer wheat and its ecological association
Authors: Wang Ji-Rui , Wei Yu-Ming , Long Xiang-Yu , Yan Ze-Hong , Nevo Eviatar , Baum Bernard R , Zheng You-Liang 
Published: March 2008

Abstract

Background
α-Amylase inhibitors are attractive candidates for the control of seed weevils, as these insects are highly dependent on starch as an energy source. In this study, we aimed to reveal the structure and diversity of dimeric α-amylase inhibitor genes in wild emmer wheat from Israel and to elucidate the relationship between the emmer wheat genes and ecological factors using single nucleotide polymorphism (SNP) markers. Another objective of this study was to find out whether there were any correlations between SNPs in functional protein-coding genes and the environment.

Results
The influence of ecological factors on the genetic structure of dimeric α-amylase inhibitor genes was evaluated by specific SNP markers. A total of 244 dimeric α-amylase inhibitor genes were obtained from 13 accessions in 10 populations. Seventy-five polymorphic positions and 74 haplotypes were defined by sequence analysis. Sixteen out of the 75 SNP markers were designed to detect SNP variations in wild emmer wheat accessions from different populations in Israel. The proportion of polymorphic loci P (5%), the expected heterozygosity He, and Shannon's information index in the 16 populations were 0.887, 0.404, and 0.589, respectively. The populations of wild emmer wheat showed great diversity in gene loci both between and within populations. Based on the SNP marker data, the genetic distance of pair-wise comparisons of the 16 populations displayed a sharp genetic differentiation over long geographic distances. The values of P, He, and Shannon's information index were negatively correlated with three climatic moisture factors, whereas the same values were positively correlated by Spearman rank correlation coefficients' analysis with some of the other ecological factors.

Conclusion
The populations of wild emmer wheat showed a wide range of diversity in dimeric α-amylase inhibitors, both between and within populations. We suggested that SNP markers are useful for the estimation of genetic diversity of functional genes in wild emmer wheat. These results show significant correlations between SNPs in the α-amylase inhibitor genes and ecological factors affecting diversity. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs, and the SNPs could be classified into several categories as ecogeographical predictors. It was suggested that the SNPs in the α-amylase inhibitor genes have been subjected to natural selection, and ecological factors had an important evolutionary influence on gene differentiation at specific loci.
The immunomodulator PSK induces in vitro cytotoxic activity in tumour cell lines via arrest of cell cycle and induction of apoptosis
Authors: Jiménez-Medina Eva , Berruguilla Enrique , Romero Irene , Algarra Ignacio , Collado Antonia , Garrido Federico , Garcia-Lora Angel 
Published: March 2008

Abstract

Background
Protein-bound polysaccharide (PSK) is derived from the CM-101 strain of the fungus Coriolus versicolor and has shown anticancer activity in vitro and in in vivo experimental models and human cancers. Several randomized clinical trials have demonstrated that PSK has great potential in adjuvant cancer therapy, with positive results in the adjuvant treatment of gastric, esophageal, colorectal, breast and lung cancers. These studies have suggested the efficacy of PSK as an immunomodulator of biological responses. The precise molecular mechanisms responsible for its biological activity have yet to be fully elucidated.

Methods
The in vitro cytotoxic anti-tumour activity of PSK has been evaluated in various tumour cell lines derived from leukaemias, melanomas, fibrosarcomas and cervix, lung, pancreas and gastric cancers. Tumour cell proliferation in vitro was measured by BrdU incorporation and viable cell count. Effect of PSK on human peripheral blood lymphocyte (PBL) proliferation in vitro was also analyzed. Studies of cell cycle and apoptosis were performed in PSK-treated cells.

Results
PSK showed in vitro inhibition of tumour cell proliferation as measured by BrdU incorporation and viable cell count. The inhibition ranged from 22 to 84%. Inhibition mechanisms were identified as cell cycle arrest, with cell accumulation in G0/G1 phase and increase in apoptosis and caspase-3 expression. These results indicate that PSK has a direct cytotoxic activity in vitro, inhibiting tumour cell proliferation. In contrast, PSK shows a synergistic effect with IL-2 that increases PBL proliferation.

Conclusion
These results indicate that PSK has cytotoxic activity in vitro on tumour cell lines. This new cytotoxic activity of PSK on tumour cells is independent of its previously described immunomodulatory activity on NK cells.
Increased expression of EphA7 correlates with adverse outcome in primary and recurrent glioblastoma multiforme patients
Authors: Wang Lin-Fang , Fokas Emmanouil , Juricko Janko , You An , Rose Frank , Pagenstecher Axel , Engenhart-Cabillic Rita , An Han-Xiang 
Published: March 2008

Abstract

Background
Malignant gliomas are lethal cancers, highly dependent on angiogenesis and treatment options and prognosis still remain poor for patients with recurrent glioblastoma multiforme (GBM). Ephs and ephrins have many well-defined functions during embryonic development of central nervous system such as axon mapping, neural crest cell migration, hindbrain segmentation and synapse formation as well as physiological and abnormal angiogenesis. Accumulating evidence indicates that Eph and ephrins are frequently overexpressed in different tumor types including GBM. However, their role in tumorigenesis remains controversial, as both tumor growth promoter and suppressor potential have been ascribed to Eph and ephrins while the function of EphA7 in GBM pathogenesis remains largely unknown.

Methods
In this study, we investigated the immunohistochemical expression of EphA7 in a series of 32 primary and recurrent GBM and correlated it with clinical pathological parameters and patient outcome. In addition, intratumor microvascular density (MVD) was quantified by immunostaining for endothelial cell marker von Willebrand factor (vWF).

Results
Overexpression of EphA7 protein was predictive of the adverse outcome in GBM patients, independent of MVD expression (p = 0.02). Moreover, high density of MVD as well as higher EphA7 expression predicted the disease outcome more accurately than EphA7 variable alone (p = 0.01). There was no correlation between MVD and overall survival or recurrence-free survival (p > 0.05). However, a statistically significant correlation between lower MVD and tumor recurrence was observed (p = 0.003).

Conclusion
The immunohistochemical assessment of tissue EphA7 provides important prognostic information in GBM and would justify its use as surrogate marker to screen patients for tyrosine kinase inhibitor therapy.
Process and effects of a community intervention on malaria in rural Burkina Faso: randomized controlled trial
Authors: Kouyaté Bocar , Somé Florent , Jahn Albrecht , Coulibaly Boubacar , Eriksen Jaran , Sauerborn Rainer , Gustafsson Lars , Tomson Göran , Becher Heiko , Mueller Olaf 
Published: March 2008

Abstract

Background
In the rural areas of sub-Saharan Africa, the majority of young children affected by malaria have no access to formal health services. Home treatment through mothers of febrile children supported by mother groups and local health workers has the potential to reduce malaria morbidity and mortality.

Methods
A cluster-randomized controlled effectiveness trial was implemented from 2002–2004 in a malaria endemic area of rural Burkina Faso. Six and seven villages were randomly assigned to the intervention and control arms respectively. Febrile children from intervention villages were treated with chloroquine (CQ) by their mothers, supported by local women group leaders. CQ was regularly supplied through a revolving fund from local health centres. The trial was evaluated through two cross-sectional surveys at baseline and after two years of intervention. The primary endpoint of the study was the proportion of moderate to severe anaemia in children aged 6–59 months. For assessment of the development of drug efficacy over time, an in vivo CQ efficacy study was nested into the trial. The study is registered under http://www.controlled-trials.com (ISRCTN 34104704).

Results
The intervention was shown to be feasible under program conditions and a total of 1.076 children and 999 children were evaluated at baseline and follow-up time points respectively. Self-reported CQ treatment of fever episodes at home as well as referrals to health centres increased over the study period. At follow-up, CQ was detected in the blood of high proportions of intervention and control children. Compared to baseline findings, the prevalence of anaemia (29% vs 16%, p < 0.0001) and malaria parameters such as prevalence of P. falciparum parasitaemia, fever and palpable spleens was lower at follow-up but there were no differences between the intervention and control group. CQ efficacy decreased over the study period but this was not associated with the intervention.

Discussion
The decreasing prevalence of malaria morbidity including anaemia over the study period can be explained by an overall increase of malaria prevention and treatment activities in the study area. The lack of effectiveness of the intervention was likely caused by contamination, pre-existing differences in the coverage of malaria treatment in both study groups and an unexpectedly rapid increase of resistance against CQ, the first-line treatment drug at the time of the study.
A stochastic automaton shows how enzyme assemblies may contribute to metabolic efficiency
Authors: Amar Patrick , Legent Guillaume , Thellier Michel , Ripoll Camille , Bernot Gilles , Nystrom Thomas , Saier Milton H , Norris Vic 
Published: March 2008

AbstractBackgroundThe advantages of grouping enzymes into metabolons and into higher order structures have long been debated. To quantify these advantages, we have developed a stochastic automaton that allows experiments to be performed in a virtual bacterium with both a membrane and a cytoplasm. We have investigated the general case of transport and metabolism as inspired by the phosphoenolpyruvate:sugar phosphotransferase system (PTS) for glucose importation and by glycolysis.ResultsWe show that PTS and glycolytic metabolons can increase production of pyruvate eightfold at low concentrations of phosphoenolpyruvate. A fourfold increase in the numbers of enzyme EI led to a 40% increase in pyruvate production, similar to that observedin vivoin the presence of glucose. Although little improvement resulted from the assembly of metabolons into a hyperstructure, such assembly can generate gradients of metabolites and signaling molecules.Conclusionin silicoexperiments may be performed successfully using stochastic automata such as HSIM (Hyperstructure Simulator) to help answer fundamental questions in metabolism about the properties of molecular assemblies and to devise strategies to modify such assemblies for biotechnological ends.
N,O-Heterocycles as synthetic intermediates
Authors: Bates Roderick W. , Boonsombat Jutatip , Lu Yongna , Nemeth Joseph A. , Sa-Ei Kanicha , Song Ping , Peiling Cai Melody , Cranwell Philippa B. , Winbush SusAnn 
Published: March 2008

Abstract
Hydroxylamines can be cyclized under various conditions according to the nature of the unsaturation in the N-substituent. Both isoxazolidines and tetrahydrooxazines can be formed with good synthetic control. The choice of the appropriate cyclization reaction leads to syntheses of the natural products sedamine and monomorine. The related N,O-acetals are shown to undergo efficient ring-opening under Sakurai conditions.
Heterocycle synthesis via radical reactions
Authors: Naito Takeaki 
Published: March 2008

Abstract
A novel synthetic method for the preparation of nitrogen-containing heterocycles via the route involving domino-type radical addition/cyclization reaction of oxime ethers is described. Alkyl radical addition/cyclization of oxime ethers carrying an appropriate leaving group proceeded smoothly to form the alkylated nitrogen-containing heterocyclic compounds. Additionally, tin-mediated radical addition/cyclization/elimination (RACE) reaction of oxime ethers is newly found and successfully applied to an asymmetric total synthesis of (-)-martinellic acid.
Exploiting the borono-Mannich reaction in bioactive alkaloid synthesis
Authors: Pyne Stephen G. , Au Christopher W. G. , Davis Andrew S. , Morgan Ian R. , Ritthiwigrom Thunwadee , Yazici Arife 
Published: March 2008

Abstract
We have demonstrated that the borono-Mannich reaction is a versatile and efficient reaction for the diastereoselective preparation of chiral 1,2-amino alcohols. These Mannich products are valuable starting materials as shown in this report by the synthesis of bioactive polyhydroxylated pyrrolizidine and indolizidine alkaloids. Initial studies, directed at the more complex Stemona alkaloids and using the borono-Mannich reaction on cyclic N-acyliminium ions, are encouraging, as demonstrated by the synthesis of the pyrido[1,2-a]azepine core structure of stemocurtisinol.
Greener and expeditious synthesis of bioactive heterocycles using microwave irradiation
Authors: Polshettiwar Vivek , Varma Rajender S. 
Published: March 2008

Abstract
The utilization of green chemistry techniques is dramatically reducing chemical waste and reaction times as has recently been proven in several organic syntheses and chemical transformations. To illustrate these advantages in the synthesis of bioactive heterocycles, we have studied various environmentally benign protocols that involve greener alternatives. Microwave (MW) irradiation of neat reactants catalyzed by the surfaces of recyclable mineral supports, such as alumina, silica, clay, or their "doped" versions, enables the rapid one-pot assembly of heterocyclic compounds, such as flavonoids, related benzopyrans, and quinolone derivatives. The strategy to assemble oxygen and nitrogen heterocycles from in situ generated reactive intermediates via enamines or using hypervalent iodine reagents is described. Examples of multicomponent reactions that can be adapted for rapid parallel synthesis include solventless synthesis of dihydropyrimidine-2(1H)-ones (Biginelli reaction), imidazo[1,2-a]annulated pyridines, pyrazines, and pyrimidines (Ugi reaction). The relative advantages of greener pathways, which use MW irradiation and eco-friendly aqueous reaction medium, for the synthesis of various heterocycles, such as N-aryl azacycloalkanes, isoindoles, 1,3-dioxane, 1,3,4-oxadiazole, 1,3,4-thiadiazole, pyrazole, and diazepines, are also summarized.
Classifying Borel automorphisms
Authors: Clemens John D. 
Published: March 2008

§1. Introduction. This paper considers several complexity questions regarding Borel automorphisms of a Polish space. Recall that a Borel automorphism is a bijection of the space with itself whose graph is a Borel set (equivalently, the inverse image of any Borel set is Borel). Since the inverse of a Borel automorphism is another Borel automorphism, as is the composition of two Borel automorphisms, the set of Borel automorphisms of a given Polish space forms a group under the operation of composition. We can also consider the class of automorphisms of all Polish spaces. We will be primarily concerned here with the following notion of equivalence:Definition 1.1. Two Borel automorphisms f and g of the Polish spaces X and Y are said to be Borel isomorphic, f ≅ g, if they are conjugate, i.e. there is a Borel bijection φ: X → Y such that φ ∘ f = g ∘ φ.We restrict ourselves to automorphisms of uncountable Polish spaces, as the Borel automorphisms of a countable space are simply the permutations of the space. Since any two uncountable Polish spaces are Borel isomorphic, any Borel automorphism is Borel isomorphic to some automorphism of a fixed space. Hence, up to Borel isomorphism we can fix a Polish space and represent any Borel automorphism as an automorphism of this space. We will use the Cantor space 2ω (with the product topology) as our representative space.
Intuitionistic logic freed of all metarules
Authors: Corsi Giovanna , Tassi Gabriele 
Published: March 2008

AbstractIn this paper we present two calculi for intuitionistic logic. The first one. IG, is characterized by the fact that every proof-search terminates and termination is reached without jeopardizing the subformula property. As to the second one, SIC, proof-search terminates, the subformula property is preserved and moreover proof-search is performed without any recourse to metarules, in particular there is no need to back-track. As a consequence, proof-search in the calculus SIC is accomplished by a single tree as in classical logic.
Consequences of the provability of NP ⊆ P/poly
Authors: Cook Stephen , Krajíček Jan 
Published: March 2008

AbstractWe prove the following results: (i) PV proves NP ⊆ P/poly iff PV proves coNP ⊆ NP/O(1). (ii) If PV proves NP ⊆ P/poly then PV proves that the Polynomial Hierarchy collapses to the Boolean Hierarchy, (iii) proves NP ⊆ P/poly iff proves coNP ⊆ NP/O(log n). (iv) If proves NP ⊆ P/poly then proves that the Polynomial Hierarchy collapses to PNP[log n]. (v) If proves NP ⊆ P/poly then proves that the Polynomial Hierarchy collapses to PNP.Motivated by these results we introduce a new concept in proof complexity: proof systems with advice, and we make some initial observations about them.
An untyped higher order logic with Y combinator
Authors: Andrews James H. 
Published: March 2008

AbstractWe define a higher order logic which has only a notion of sort rather than a notion of type, and which permits all terms of the untyped lambda calculus and allows the use of the Y combinator in writing recursive predicates. The consistency of the logic is maintained by a distinction between use and mention, as in Gilmore's logics. We give a consistent model theory, a proof system which is sound with respect to the model theory, and a cut-elimination proof for the proof system. We also give examples showing what formulas can and cannot be used in the logic.
Mechanistic Insights into Transition Metal‐Catalysed Oxidation of a Hydroxamic Acid with in situ Diels–Alder Trapping of the Acyl Nitroso Derivative
Authors: Howard Judith A. K. , Ilyashenko Gennadiy , Sparkes Hazel A. , Whiting Andrew , Wright Allen R. 
Published: March 2008

AbstractNew insights into the mechanism for the transition metal‐mediated oxidation of hydroxamic acids to give intermediate acyl nitroso species, with subsequent hetero‐Diels–Alder trapping are presented. The activation of triphenylphosphine‐ligated ruthenium‐salen complexes is examined, and evidence is presented for the ruthenium‐oxo species which are involved in the oxidative process of the hydroxamic acid. The observation of the lack of asymmetric induction involved in the intermolecular cycloaddition process involving the intermediate acyl nitrsoso species is explained, with the aid of comparing the ruthenium‐salen‐based systems with nitrosotoluene, and copper(I)/copper(II) BINAP‐based catalysis of nitrosopyridine complexes. This study demonstrates the importance of secondary coordination to achieve asymmetric induction in nitroso‐Diels–Alder reactions.
Au‐Induced Polyvinylpyrrolidone Aggregates with Bound Water for the Highly Shape‐Selective Synthesis of Silica Nanostructures
Authors: Zhang Jianhui , Liu Huaiyong , Wang Zhenlin , Ming Naiben 
Published: March 2008

AbstractNovel Au‐induced polyvinylpyrrolidone (PVP) aggregates with bound water (PVP–water) were created for the highly shape‐selective synthesis of distinctive silica nanostructures, such as core–shell spheres, rods, snakes, tubes, capsules, thornlike, and dendritic morphologies. A water/PVP/n‐pentanol system was first designed to bind water to PVP, and then Au nanoparticles were used to induce the PVP–water species to aggregate into distinctive soft structures by exploiting the interplay between PVP and gold. This was confirmed by the IR absorption spectra. The bound water in the soft structures was consumed during the hydrolysis of tetraethylorthosilicate and the target silica nanostructures were obtained. The soft structures, and therefore, the silica morphologies, can be readily tuned by adjusting the experimental parameters. The tunable Au‐induced PVP–water soft structures reported herein open up new dimensions for the synthesis of distinctive nanomaterials (other than silica) that have new physicochemical properties and applications. These soft structures were also successfully extended to synthesize ZnO and SnO2 particles with remarkable shapes, such as spheres, leaves, T‐shaped structures, and dendritic morphologies.
Luminescent Excited‐State Intramolecular Proton‐Transfer (ESIPT) Dyes Based on 4‐Alkyne‐Functionalized [2,2′‐Bipyridine]‐3,3′‐diol Dyes
Authors: Ulrich Gilles , Nastasi Francesco , Retailleau Pascal , Puntoriero Fausto , Ziessel Raymond , Campagna Sebastiano 
Published: March 2008

AbstractFunctionalized 6,6′‐dimethyl‐3,3′‐dihydroxy‐2,2′‐bipyridine dyes (BP(OH)2) exhibit relatively intense fluorescence from the relaxed excited state formed by excited‐state intramolecular proton transfer (ESIPT). Bromo functionalization of (BP(OH)2) species followed by palladium(0)‐catalyzed reactions allows the connection (via alkyne tethers) of functional groups, such as the singlet‐emitter diazaboraindacene (bodipy) group or a chelating module (terpyridine; terpy). The X‐ray structure of the terpy‐based compound confirms the planarity of the 3,3′‐dihydroxy‐bipyridine unit. The new dyes exhibit relatively intense emission on the nanosecond timescale when in fluid solution, in the solid state at 298 K, and in rigid glasses at 77 K. In some cases, the excitation wavelength luminescence was observed and attributed to 1) inefficiency of the ESIPT process in particular compounds when not enough vibrational energy is introduced in the Franck–Condon state, which is populated by direct light excitation or 2) the presence of an additional excited state that deactivates to the ground state without undergoing the ESIPT process. For some selected species, the effect of the addition of zinc salts on the absorption and luminescence spectra was investigated. In particular, significant fluorescence changes were observed as a consequence of probable consecutive formation of a 1:1 and 1:2 molecular ratio of ligand/zinc adducts owing to coordination of ZnII ions by the bipyridyldiol moieties, except when an additional terpyridine subunit is present. In fact, this latter species preferentially coordinates to the ZnII ion in a 1:1 molecular ratio and further inhibits ZnII interaction. In the hybrid Bodipy/BP(OH)2 species, complete energy transfer from the BP(OH)2 to the bodipy fluorophore occurs, leading to exclusive emission from the lowest‐lying bodipy subunit.