bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation on Anti-hepatitis Viral Activity of Vitis vinifer L
Authors: Liu Tao , Zhao Jun , Li Haibo , Ma Long
Published: October 2010

Suosuo grape (Vitis vinifer L) is traditionally used as a therapeutic agent for measles and hepatitis by the ethnic Uighurs. This work aimed to investigate the anti-HBV effect of total triterpene (VTT), total flavonoids (VTF) and total polysaccharides (VTP) from Suosuo grape, and their synergistic effects were also tested. The viral antigens of cellular secretion, HBsAg and HBeAg, were determined by enzyme linked immunosorbent assay (ELISA).The quantity of HBV-DNA released in the supernatant was assayed by real-time PCR. It was found that it effectively suppressed the secretion of HBsAg and HBeAg from HepG2.2.15 cells in a dose-dependent manner, as well as the HBV DNA. The results of orthogonal design experiment showed that the combination of VTT 20 μg/mL, VTF 50 μg/mL and VTP 50 μg/mL had the best optimistic inhibitory effects on HBeAg secretion.
Prenylated Xanthones from the Bark of Garcinia xanthochymus and Their 1,1-Diphenyl-2-picrylhydrazyl (DPPH) Radical Scavenging Activities
Authors: Chen Yu , Fan Hua , Yang Guang-zhong , Jiang Yan , Zhong Fang-fang , He Hong-wu
Published: October 2010

Garcinia xanthochymus has been widely used in traditional Chinese medicine for expelling worms and removing food toxins. Bioassay-guided fractionation of an EtOAc-soluble extract of G. xanthochymus stem bark led to the isolation of six new xanthones. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques. Free-radical-scavenging activities of the isolated compounds were elucidated through DPPH method. Most of the isolated compounds showed considerable free radical scavenging activity on DPPH assay. Compound 1 exhibited effective antioxidant scavenging activity against DPPH radical with an IC50 value of 19.64 μM, and compound 6 showed the lowest activity among all the tested molecules, with an IC50 value of 66.88 μM. These findings support the notion that the plant genus Garcinia is a good source of bioactive compounds.
Le droit comparé en question(s). Entre pragmatisme et outil épistémologique
Authors: Ponthoreau Marie-Claire
Published: October 2010

Il semblerait bien que la période au cours de laquelle les comparatistes déploraient la marginalisation du droit comparé, soit révolue. Le droit comparé cependant fait toujours l’objet de controverses aussi bien quant à sa méthodologie, son rôle qu’à sa place dans le cursus académique. Les comparatistes eux-mêmes ressentent aujourd’hui plus qu’hier le besoin d’offrir une approche critique de la comparaison juridique. Cet article vise à partir des débats les plus récents et de l’assimilation de la comparaison à une directive d’interprétation à formuler des exigences d’ordre méthodologique et à rapprocher les comparatistes «traditionnels» et «post-modernistes». Il appartient aux comparatistes de prendre avec eux le meilleur de la critique développée par les postmodernistes (ceux qui valorisent l’expérience de la pluralité et de la différence). Ces derniers ont le grand mérite d’attirer l’attention sur la tâche sans borne que représente la comparaison des droits.
Méthodologie du droit comparé : bilan et prospective
Authors: Jaluzot Béatrice
Published: October 2010

Comparative law methodology is invoked by a number of authors. Yet, what each means by «comparative law» is not always clear. This work aims to present a survey of comparative law methodology, how it is perceived and its different schools of thought. In doing so, this work will bring us to question about the future of comparative law.
Responsabilité civile et naissance d’un enfant. Aperçu comparatif
Authors: Demme Géraldine , Lorentz Romain
Published: October 2010

Birth-related torts take several forms and may be distinguished, on the one hand, according to the type of plaintiff and, on the other, according to whether the child is born healthy or handicapped. Through a study of German, American, English, and French statutes and judicial decisions, one may observe that ethical and moral considerations often interfere with the legal reasoning. Taking into account non-legal criteria sometimes leads to exonerating medical professionals from liability where this cannot be legally justified when others, whose faults are objectively less serious but without any relation to the birth of a child, are held liable without hesitation. This situation is all the more unfortunate in that it denies compensation to a whole category of victims whose damages are nevertheless very real. It is therefore left to the legal community to find realistic and reasonable solutions that are based on the law.
La réception du modèle juridique français par le Code civil irakien
Authors: Al Dabbagh Harith
Published: October 2010

One of the first modern civil codifications in the Arab World, the Iraqi Civil Code is fifty-four years old today. Although it is rarely tackled by the studies of comparative law in France, it presents an obvious family tie with French law, of which it has widely followed the model. However unlike other Arab countries such as Lebanon, Egypt and Syria which adopted the Romano-Germanic system, the Iraqi Civil Code has affirmed this reception whilst reserving a rather considerable place for legal rules borrowed from Islamic Law which was at its root. By this means, the study of the Iraqi Civil Code offers a considerable interest for specialists in comparative studies. Hence, this fruitful meeting between two legal systems -with different pasts, origins, traditions, attitudes and intellectual know-how, opens the way to cooperation and prolific exchange between civilizations. This study also allows one to highlight the use of foreign laws as an instrument of legislative politics. The aim of this article is to show the most sensitive features of French law which have influenced the Iraqi Civil Code and the efforts of harmonization and integration that have resulted from this approach.
Le port du voile islamique dans le domaine scolaire en France et en Allemagne
Authors: Le Goff Aymeric
Published: October 2010

Les lois que les États français et allemand ont récemment adoptées relativement au port du voile islamique sont susceptibles de diverses interprétations et reflètent ainsi les hésitations auxquelles restent confrontés ces États quant à leur modèle de neutralité religieuse. L’État français hésite encore à abandonner un modèle de neutralité principalement fondé sur l’abstention au profit d’un modèle de promotion égalitaire des différentes religions. Si les engagements internationaux incitent à la reconnaissance d’une pleine et entière liberté d’expression religieuse au profit des élèves, cet État ne peut cependant faire fi, ni des revendications communautaires exprimées par les élèves, ni du risque d’ «une école à la carte», ni des plaintes du monde enseignant directement confronté à la gestion des troubles engendrés par l’hypertrophie du droit fondamental à la liberté religieuse de l’élève. L’État allemand, quant à lui, abandonne actuellement un modèle de coopération avec les Églises chrétiennes au profit d’une véritable neutralité par promotion égalitaire des différentes religions. Encouragé sinon contraint dans cette démarche par les juridictions administrative et constitutionnelle fédérales, cet État se doit toutefois de considérer les aspirations de certains Länder qui restent fortement attachés aux liens privilégiés traditionnels avec les Églises chrétiennes.
L’exercice de la tutelle des mineurs et des incapables par des personnes morales (article 242 du Code civil espagnol)
Authors: Lasarte Alvarez Carlos , Blanco Perez-Rubio Lourdes
Published: October 2010

Depuis la publication du Code civil espagnol en 1889, la tutelle sous laquelle étaient placés les mineurs et incapables était une tutelle de famille, qui était exercée uniquement par des personnes physiques. À la suite de la promulgation de la loi du 24 octobre 1983 cette situation change. En effet, en vertu de cette dernière il est établi, à l’article 242 du Code civil, la possibilité que la tutelle soit exercée par des personnes morales (différente de celle établie par la loi du 11 novembre 1987, à l’article 172 du Code civil, qui fait référence à la tutelle exercée par les administrations publiques en relation avec les mineurs se trouvant dans une situation d’abandon). Dans ce travail, on étudie le fonctionnement de ladite tutelle, en essayant de répondre aux multiples questions que pose dans la pratique ce genre de tutelle, au caractère d’une réglementation spécifique qui permette de déterminer, par exemple, comment se réalise la désignation du tuteur personne morale, si les parents du mineur ou d’un majeur incapable peuvent mener à bien telle désignation, les excuses que la personne morale désignée peut présenter, les causes de changement, etc.
La révision de la Constitution de Roumanie concernant les langues des minorités nationales : un modèle à suivre
Authors: Vrabié Genoveva
Published: October 2010

The problem of the languages of national minorities in Romania •including the one regarding the revision of constitutional regulations in the field •is approached by the author in a vast perspective which concerns both the defence of the national language as well as the defence of the languages of the minorities. Also, these two categories of policies are considered within the scope of the democratisation of the Romanian society on the one hand and of the integration of the state in supernational structures, such as the European Council, the European Union etc. on the other hand. By analysing the two texts added to the Constitution at the time of its revision in 2003 in the light of similar texts of other European constitutions the author argues that the Romanian legislator has found appropriate means to associate two constitutional principles which appear to be in conflict: that of the consecration of the Romanian language as the official language of the country and the one regarding the linguistic rights of national minorities. In conclusion, the author argues that the regulation of the linguistic rights of the national minorities in Romania constitutes a model to be followed by other states. Viewed as ethnic groups with a long experience of co-existence, with common aspirations and values, the Romanians and the national minorities in Romania have succeeded to develop linguistic policies which make living together both possible and peaceful while orienting at the same time the social activity as a whole towards the accomplishment of the fundamental objectives of the unitary Romanian state.
L’indemnisation du risque thérapeutique en droit anglais et la possibilité d’un rapprochement des systèmes européens
Authors: Taylor Simon
Published: October 2010

L’introduction dans les pays scandinaves et en France de régimes législatifs d’indemnisation pour certaines catégories de victimes d’accidents médicaux contribue à différencier lourdement ces systèmes par rapport à d’autres au sein de l’Union européenne, qui proposent peu d’alternatifs à l’action en justice pour faute. Cet article examinera l’évolution du droit anglais en matière de responsabilité médicale, qui est passé d’une attitude de déférence vis-à-vis des médecins de la part des juges vers une position aujourd’hui plus favorable à la victime. L’augmentation significative des actions en justice dans ce domaine et leur coût financier pour la

National Health Service a soulevé des demandes de réformes législative en Angleterre. Nous considérerons des propositions récentes pour l’introduction d’un régime législatif d’indemnisation des accidents médicaux. Nous réfléchirons ensuite sur l’opportunité d’une harmonisation communautaire des règles nationales de responsabilité et d’indemnisation des victimes d’accidents médicaux.
Des principes de la conclusion du contrat dans l’acquis communautaire
Authors: Schulze Rainer
Published: October 2010

The article shows, focussing on formation of contract that the existing European Community law contains principles which can form the basis for a more coherent future European contract law in accordance with the action plan of the European Commission. These include not only fundamental principles of contract law such as freedom of contract, ensuring contractual parity in favour of the structurally weaker party and nondiscrimination on grounds of race, ethnic origin and gender. Moreover, one can also extract from the Acquis communautaire a series of further principles with regard to various aspects of formation of contract, such as the agreement of the parties as the basis of contractual obligation, the binding effect of pre-contractual information duties and the exercise of withdrawal rights. These principles more closely correspond to the modern developments and needs in the internal market than the principles which result from a comparison of the legal traditions of the member states. They should therefore assume a central role in the elaboration of the Common Frame of Reference for European contract law.
ModelingNymphoidesarchitecture: A morphological analysis ofNymphoides aquatica(Menyanthaceae)
Authors: Richards Jennifer H. , Dow Marlene , Troxler Tiffany
Published: October 2010

•Premise of the study: Species in the aquatic genusNymphoideshave inflorescences that appear to arise from the petioles of floating leaves. The inflorescence‐floating leaf complex can produce vegetative propagules and/or additional inflorescences and leaves. We analyzed the morphology ofN. aquaticato determine how this complex relates to whole plant architecture and whether whole plant growth is sympodial or monopodial.

•Methods: We used dissections, measurements, and microscopic observations of field‐collected plants and plants cultivated for 2 years in outdoor tanks in south Florida, USA.

•Key results:Nymphoides aquaticahad a submerged plagiotropic rhizome that produced floating leaves in an alternate/spiral phyllotaxy. Rhizomes were composed of successive sympodial units that varied in the number of leaves produced before the apex terminated. The basic sympodial unit had a prophyll that subtended a renewal‐shoot bud, a short‐petioled leaf (SPL) with floating lamina, and an inflorescence; the SPL axillary bud expanded as a vegetative propagule. Plants produced either successive basic sympodial units or expanded sympodia that intercalated long‐petioled leaves between the prophyll and the SPL.

•Conclusions:Nymphoides aquaticagrows sympodially, forming a rhizome composed of successive basic sympodia and expanded sympodial units. Variations on these types of sympodial growth help explain the branching patterns and leaf morphologies described for otherNymphoidesspecies. Monitoring how these two sympodial phases are affected by water depth provides an ecologically meaningful way to assessN. aquatica's responses to altered hydrology.
Effectiveness of home-based directly observed treatment for tuberculosis in Kweneng West subdistrict, Botswana
Authors: Mash Bob , Kabongo Diulu
Published: October 2010

Background: Tuberculosis (TB) and HIV are major public health problems in Botswana. In the face of growing TB notification rates, a low cure rate, human resource constraints and poor accessibility to health facilities, Botswana Ministry of Health decided to offer home-based directly observed treatment (DOT) using community volunteers.Objectives: The aim of this study was to assess the outcomes of home-based directly observed treatment (HB-DOT) versus facility-based, directly observed treatment (FB-DOT) in the Kweneng West subdistrict in Botswana and to explore the acceptability of HB-DOT among TB patients,community volunteers and health workers.Method: A quantitative, observational study using routinely collected TB data from 405 TB patientswas conducted and combined with 20 qualitative in-depth interviews.Results: The overall cure rate for smear-positive pulmonary TB patients was 78.5%. Treatmentoutcomes were not statistically different between FB-DOT and HB-DOT. Contact tracing was significantly better in FB-DOT patients. Interviews revealed advantages and disadvantages for both FB and HB options and that flexibility in the choice or mix of options was important. A number of suggestions were made by the interviewees to improve the HB-DOT programme.Conclusion: HB-DOT is at least as good as FB-DOT in terms of the treatment outcomes, but attention must be given to contact tracing. HB-DOT offers some patients the flexibility they need to adhere to TB treatment and community volunteers may be strengthened by ongoing training and support from health workers, financial incentives and provision of basic equipment.
Irrigation enhances precipitation at the mountains downwind
Authors: Jódar J. , Carrera J. , Cruz A.
Published: October 2010

Abstract. Atmospheric circulation models predict an irrigation-rainfall feedback. However, actual field evidences for local evaporation recycling (moisture feedback) are weak. We present strong field evidence for an increase in rainfall at the mountains located downwind of irrigated zones. We chose two regions, located in semiarid southern Spain, where irrigation started at a well defined date, and we analyzed rainfall statistics before and after the beginning of irrigation. Analyzed statistics include the variation of (1) mean rainfall Δ P, (2) ratio of monthly precipitation to annual precipitation Δ r, and (3) number of months with noticeable rainfall episodes Δ Pmin after a shifting from unirrigated to irrigated conditions. All of them show statistically significant increases. Δ P and Δ r show larger and more statistically significant variations in June and July than in August. They also tend to increase with the annual volume of water applied in the neighbouring upwind irrigation lands. Increases in Δ Pmin are statistically significant during the whole summer. That is, the number of noticeable rainfall events displays a relevant increase after irrigation. In fact, it is this number, rather than sporadic large rainfall episodes what makes the summers wetter. The increase in rainfall, while statistically significant, is distributed over a broad region, so that it is of little relevance from a water resources perspective, although it may enhance vegetation yield.
Intraoperative Floppy Iris Syndrome Associated with Risperidone Intake
Authors: Ford Rebecca L. , Sallam Ahmed , Towler Hamish M.A.
Published: October 2010

Purpose

Intraoperative floppy iris syndrome (IFIS) has been strongly associated with intake of selective α1 adrenergic blockers, particularly tamsulosin. Intraoperative floppy iris syndrome has also been linked to the use of other drugs with some a antagonist activity.

Methods

We identified patients on long-term treatment with the antipsychotic agent risperidone who showed typical features of IFIS during cataract surgery.

Results

We report 3 eyes in 2 patients taking risperidone in which typical features of IFIS were noted during cataract surgery.

Conclusions

Risperidone is a widely prescribed drug in psychiatric practice and has α-blocking actions as well as strong affinity for serotonin 2A receptors. Ophthalmologists should be aware of the possible association with IFIS when performing cataract surgery on patients taking risperidone.
Metal‐Organic Frameworks: A Rapidly Growing Class of Versatile Nanoporous Materials
Authors: Meek Scott T. , Greathouse Jeffery A. , Allendorf Mark D.
Published: October 2010

Metal‐organic frameworks (MOFs) represent a new class of hybrid organic‐inorganic supramolecular materials comprised of ordered networks formed from organic electron donor linkers and metal cations. They can exhibit extremely high surface areas, as well as tunable pore size and functionality, and can act as hosts for a variety of guest molecules. Since their discovery, MOFs have enjoyed extensive exploration, with applications ranging from gas storage to drug delivery to sensing. This review covers advances in the MOF field from the past three years, focusing on applications, including gas separation, catalysis, drug delivery, optical and electronic applications, and sensing. We also summarize recent work on methods for MOF synthesis and computational modeling.
Pre‐eminence and persistence of immature natural killer cells in acute myeloid leukemia patients in first complete remission
Authors: Dauguet Nicolas , Récher Christian , Demur Cécile , Fournié Jean‐Jacques , Poupot Mary , Poupot Rémy
Published: October 2010

Despite substantial progress in the treatment of AML, a proportion of patients do not achieve first complete remission (1st CR) with the induction chemotherapy, and, among patients achieving it, a majority is expected to relapse within three years. As allogeneic hematopoietic stem cell transplantation has been established as the most effective form of antileukemic therapy in patients with AML in remission, many studies have focused on the reconstitution and the functionality of the innate immune system in this context, especially regarding cytotoxic effectors such as natural killer (NK) cells. On the contrary, very few data are available concerning the innate immune system of patients in 1st CR. Herein we investigated the phenotype of autologous NK cells of AML patients in 1st CR. We showed that immature NK cells were pre‐eminent in the blood of these patients and that this immature phenotype was persistent during the first months after 1st CR. Am. J. Hematol., 2010. © 2010 Wiley‐Liss, Inc.
Hubble parameter in QCD Universe for finite bulk viscosity
Authors: Tawfik A. , Wahba M. , Mansour H. , Harko T.
Published: October 2010

We consider the influence of the perturbative bulk viscosity on the evolution of the Hubble parameter in the QCD era of the early Universe. For the geometry of the Universe we assume the homogeneous and isotropic Friedmann‐Lemaitre‐Robertson‐Walker metric, while the background matter is assumed to be characterized by barotropic equations of state, obtained from recent lattice QCD simulations, and heavy‐ion collisions, respectively. Taking into account a perturbative form for the bulk viscosity coefficient, we obtain the evolution of the Hubble parameter, and we compare it with its evolution for an ideal (non‐viscous) cosmological matter. A numerical solution for the viscous QCD plasma in the framework of the causal Israel‐Stewart thermodynamics is also obtained. Both the perturbative approach and the numerical solution qualitatively agree in reproducing the viscous corrections to the Hubble parameter, which in the viscous case turns out to be slightly different as compared to the non‐viscous case. Our results are strictly limited within a very narrow temperature‐ or time‐interval in the QCD era, where the quark‐gluon plasma is likely dominant.
Evaluation of block shear properties of selected extreme‐pH structural adhesives by short‐term exposure test
Authors: Zhang Yaolin , Wang Xiang‐Ming , Casilla Romulo , Cooper Paul , Huang Zeen , Wang Xiaodong
Published: October 2010

Nine structural adhesives with varying pH were selected to examine the effect of adhesive pH on wood–adhesive bond quality. The adhesives evaluated included four highly alkaline phenol–formaldehyde, one intermediate pH phenol–resorcinol–formaldehyde, two acidic melamine–urea–formaldehyde, and two acidic melamine–formaldehyde resins. Block shear specimens were prepared using Douglas‐fir and black spruce wood. The adhesive performance was evaluated by measuring the shear properties (strength and wood failure) of the specimens tested at the dry and vacuum–pressure–redry (VPD) conditions. Adhesive pH, test condition, and wood species showed significant effects on shear properties. The different adhesives performed differently at the dry and VPD conditions. The high‐pH adhesives (phenol–formaldehyde and phenol–resorcinol–formaldehyde) showed similar high wood failures at both test conditions and performed better than the low‐pH adhesives (melamine–formaldehyde and melamine–urea–formaldehyde), especially after the VPD conditioning. The low‐pH adhesives showed high wood failure at the dry condition, but wood failure decreased significantly after VPD conditioning for both species, indicating that the low‐pH adhesives were less durable than the high‐pH adhesives. High‐pH adhesives did not have a negative impact on the strength of the bonded specimens. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Steady shear and viscoelastic properties of a micro‐crosslinked acrylamide‐based terpolymer
Authors: Zhong Chuanrong , Meng Xianghao , Deng Jun
Published: October 2010

A water‐soluble micro‐crosslinked associating polymer (PASA‐PL): poly (acrylamide/butyl styrene/sodium 2‐acrylamido‐2‐methylpropane sulphonate) (PASA)–phenolic aldehyde (PL) was prepared to reduce the critical associated concentration and enhance the thickening properties for the linear PASA polymer in aqueous and brine solutions. The consecutive steady shear and viscoelastic properties were investigated to explore the correlations between the rheologic performance and supramolecular structures for the PASA‐PL brine solutions. Upon consecutive steady shear, the intermolecular hydrophobic association is greatly reinforced because of the expansion of the coiled PASA‐PL chains at the suitable shear rate, and the brine solution exhibits obvious shear thickening behavior. The steady shear results show that the intermolecular hydrophobic association is reversible, and that the polymer chains do not degrade upon shearing. The PASA‐PL brine solutions with 50 g L−1 NaCl have predominantly elastic character over the angular frequency range at the polymer concentration higher than 1.0 g L−1, which is remarkably strengthened with a slight increase in polymer concentration. The PASA‐PL brine solutions display a salt‐thickening effect and predominantly exhibit elastic character over the angular frequency range at 10–50 g L−1 NaCl. These results demonstrate that the viscoelastic behavior of the PASA‐PL solutions mainly depends on the formation of hydrophobically associated structures via the intermolecular association strengthened by the micro‐crosslink of PASA with PL. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Oligocarbonate diols from ethylene carbonate—Optimization of the synthesis process
Authors: Tomczyk Karolina M. , Parzuchowski Pawel G. , Rokicki Gabriel
Published: October 2010

Oligocarbonate diols due to their resistance to oxidation and hydrolysis are particularly valuable components of polyurethanes for biomedical applications. It was shown that for their synthesis “green monomer,” ethylene carbonate can be used in the reaction with 1,6‐hexanediol, instead of usually applied toxic and harmful phosgene. Depending on reaction conditions, besides ester exchange leading to the desired product, competitive etherification is often observed. To optimize the reaction conditions leading to oligocarbonates of high molecular weight without oxyethylene fragments, the method of an experimental design was applied. Such approach enabled the estimation of the influence of reaction temperature, ethylene carbonate to 1,6‐hexanediol molar ratio and catalyst (NaCl) concentration on the molar mass of oligocarbonate diol, content of ether bonds and reaction time. Application of central composite method as an experimental design allowed not only to choose the optimal set of conditions, but also the coefficients of the regression equation were interpreted in a chemical way. Oligocarbonate diols obtained under optimal conditions were used for synthesis poly(urethane‐urea)s which exhibited very good mechanical properties (tensile strength 45–50 MPa and elongation at break up to 500%). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Improving the processability of biodegradable polymer by stearate additive
Authors: Yu Tao , Luo Faliang , Zhao Ying , Wang Dujin , Wang Fosong
Published: October 2010

Maleated poly(propylene carbonate)/calcium stearate (MAPPC/CaSt2) composite was prepared through melt‐extruding poly(propylene carbonate) (PPC) with maleic anhydride and CaSt2. The processability, thermal stability, interaction between two components as well as the morphology of the composites were systematically characterized. The flow instability of biodegradable PPC was greatly alleviated due to the incorporation of stearate additive in polymer matrix. It was found that the MAPPC and MAPPC/CaSt2 composites were more thermostable than pristine PPC under melt‐processing conditions. The melt fluidity of the composites was noticeably superior to that of MAPPC, arising from the lubricating effect of CaSt2 on the polymer/barrel wall interface as well as from the improvement of resistance to thermal degradation of the composite. The coordination interaction between MAPPC and calcium ion also contributes to the enhanced thermal stability and high melt stability of composites. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of acid and pH value on the photografting initiated by aliphatic ketones in aqueous solutions
Authors: Jin Enquan , Xie Mingyang , Gao Yue , Wang Huiliang
Published: October 2010

The photografting of methacrylic acid (MAA) onto high‐density polyethylene (HDPE) initiated by aliphatic ketones (acetone, butanone, and cyclohexanone) in aqueous solutions with different pH values adjusted by adding different amount of mineral acids was reported. Acids significantly enhanced the photografting yield, and the extent of grafting generally increased with decreasing pH value. The effect of pH value on the grafting reactions varied with the acid used. The grafting of MAA onto HDPE surface was confirmed with FTIR and SEM characterizations. The water absorbency of the grafted p‐MAA varied with the extent of grafting. When the extent of grafting was less than 2000–3000 μg/cm2, grafted p‐MAA absorbed about 25–30% water, whereas at higher extent of grafting, it absorbed about 50% water. The mechanism of the acid enhancement of the photografting of MAA initiated by aliphatic ketones in aqueous solutions is believed to be attributed to the change of the solubility of monomer in the solution and the conformation of grafted chains, both are favorable for accelerating grafting reactions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Ten years of experience in the rearing of young freshwater pearl mussels (Margaritifera margaritifera)
Authors: Schmidt Christine , Vandré Robert
Published: October 2010

In rearing experiments performed between 1997 and 2007, captive‐bred juvenile mussels were harvested shortly after they had dropped off their host fish, and exposed to different types of cages and holding systems.

Survival of juveniles ranged from 0 to 92% in the first 4 months, but the mean annual mortality was high in all trials and with all systems. In three trials with sheet cages and sediment boxes exposed to mussel rivers from an initial number of 1440 to 1660 only one to eight mussels reached 4 years of age.

With the exception of mussels kept in spring water no relationship between growth and survival was observed.

Low survival rates were obtained in sheet cages exposed to very oligotrophic and highly eutrophic brook stretches. Several natural sites that were lacking recruitment in the wild nevertheless showed good results in the cages.

All holding systems showed irregular variations in survival rates. Pairs of sheet cages showed no correlation between the survival of mussels in the adjacent cages. In contrast, growth rates were correlated.

No relationship could be found between the growth or survival in sheet cages at different sites and brooks and the corresponding data on water chemistry.

The systems tested for rearing young mussels involving a minimal time and effort in the natural habitat were not successful due to the elevated mortality rates of juveniles.

The rearing success of young pearl mussels in cages in the water flow of mussel rivers gives no information about the suitability of these sites for natural reproduction. Thus, to find potential natural habitats for Margaritifera, it is imperative to survey water quality, sediments and habitat structure. Copyright © 2010 John Wiley & Sons, Ltd.
Does reintroduction stabilize the population of the critically endangered gharial (Gavialis gangeticus, Gavialidae) in Chitwan National Park, Nepal?
Authors: Ballouard Jean‐Marie , Priol Pauline , Oison Jean , Ciliberti Alexandre , Cadi Antoine
Published: October 2010

Despite conservation programmes (India 1975, Nepal 1978) gharial populations (Gavialis gangeticus) have declined over their entire distribution range. Information about the current status and main threats is needed to implement effective conservation measures.

This study presents a survey (2003/2004) of the largest Nepalese gharial population in the Chitwan National Park that has benefited from regular re‐introduction of young gharials since 1981.

Population size estimates fluctuate between 34 (2003) and 38 (2004). The reintroduction programme, although of limited success, has helped to maintain the gharial population.

Gharials bask preferentially in large sand banks, and these sites must be protected.

The main threats are from a dam that causes fish depletion and flushes gharials from the protected area, sand mining and grazing that destroy basking sites, fishing that causes food shortage, drift nets that kill gharial, and water pollution.

Improvement in the survival of reintroduced gharials is needed. Strict protection of preferred basking sites and prohibition of fishing in the main settling zones are the principal conservation measures while in the long term, education and participatory management by local people are also necessary. Copyright © 2010 John Wiley & Sons, Ltd.
Infection with an intestinal helminth parasite reduces Freund's complete adjuvant–induced monoarthritis in mice
Authors: Shi Meiqing , Wang Arthur , Prescott David , Waterhouse Christopher C. M. , Zhang Shuren , McDougall Jason J. , Sharkey Keith A. , McKay Derek M.
Published: October 2010

Objective

Assessment of infection with helminth parasites in murine models of disease could identify antiinflammatory mechanisms that translate into treatments for arthritic disease. The aim of this study was to test the ability of infection with the tapeworm Hymenolepis diminuta to ameliorate Freund's complete adjuvant (CFA)–induced monoarthritis in mice.

Methods

Mice received CFA with or without H diminuta, and knee swelling, pain, and measures of inflammation were assessed.

Results

Injection of CFA resulted in rapid (within 24 hours) and sustained (lasting 20 days) knee swelling, a decreased pain threshold, increased blood flow to the knee, and increased production of tumor necrosis factor α and interleukin‐12p40 (IL‐12p40). In mice that were infected with H diminuta 8 days prior to receiving CFA, the severity of arthritis was reduced as assessed by these indices of inflammation and infection 2 days after CFA injection and resulted in more rapid resolution of knee swelling. This antiarthritic effect required a viable infection and was dependent on adaptive immunity, because infection with H diminuta did not protect mice lacking T cells and B cells or the IL‐4 receptor α chain from CFA‐induced inflammation. Interleukin‐10 was of prime importance in the antiarthritic effect, because IL‐10–knockout mice were not protected by infection, the antiarthritic effect was ablated by use of neutralizing IL‐10 antibodies, and transfer of CD4+ cells from infected wild‐type mice but not IL‐10–knockout mice significantly reduced CFA‐induced knee swelling.

Conclusion

In mice, the adaptive immune response to infection with H diminuta involves mobilization of IL‐10, which has the concomitant advantage of dampening the innate immune responses that drive CFA‐induced joint inflammation.
Iridium‐Catalyzed Asymmetric Hydrogenation of Unfunctionalized, Trialkyl‐Substituted Olefins
Authors: Wang Aie , Fraga Rui P. A. , Hörmann Esther , Pfaltz Andreas
Published: October 2010

Chiral iridium complexes with bicyclic pyridine‐based N,P ligands have emerged as efficient catalysts for the enantioselective hydrogenation of unfunctionalized trialkyl‐substituted olefins. Optimization of the reaction conditions by variation of the solvent, pressure, and temperature led to enantiomeric excesses of up to 99 %. Three pure alkenes, (E)‐2‐cyclohexyl‐2‐butene and (E)‐ and (Z)‐3,4‐dimethyl‐2‐pentene were converted into the corresponding chiral alkanes with 97 %, 94 %, and 93 % ee, respectively. Hydrogenation of the three CC bonds of both α‐ and γ‐tocotrienyl acetate led to α‐ and γ‐tocopheryl acetate with very high diastereoselectivity. The same catalysts were successfully applied in the hydrogenation of trisubstituted alkenes with a carboxylic ester or a keto group in the γ position. This reaction was used as a key step in a highly enantioselective synthesis of the pheromone of the caddisfly Hesperophylax occidentalis. The hydrogenation of a structurally analogous allylic alcohol also gave high enantioselectivities.
Hydrophobic polycationic coatings disinfect poliovirus and rotavirus solutions
Authors: Larson Alyssa M. , Hsu Bryan B. , Rautaray Debabrata , Haldar Jayanta , Chen Jianzhu , Klibanov Alexander M.
Published: October 2010

Coating surfaces with N‐alkylated polyethylenimines (PEIs), namely branched N,N‐hexyl,methyl‐PEI via covalent attachment to glass or linear N,N‐dodecyl,methyl‐PEI by physical deposition (“painting”) onto polyethylene, enables the resultant materials to quickly and efficiently disinfect aqueous solutions of (non‐enveloped) poliovirus and rotavirus. Biotechnol. Bioeng. 2011; 108:720–723. © 2010 Wiley Periodicals, Inc.
Purification of monomeric mAb from associated aggregates using selective desorption chromatography in hydroxyapatite systems
Authors: Morrison Christopher J. , Gagnon Pete , Cramer Steven M.
Published: October 2010

Selective desorption on ceramic hydroxyapatite (CHT) was implemented for the purification of monomeric monoclonal antibody (mAb) from associated aggregates and other post‐protein A step impurities. A robotic liquid handling system was employed to carry out a parallel batch screen of selective desorbents on a post‐protein A step mAb mixture. The effect of different phosphate concentrations was also investigated. Selective batch separations were achieved between monomeric mAb and associated aggregates/impurities. The batch screen results also established optimal mobile phase conditions for each selective desorbent. These initial batch results were then used to guide column separations, and baseline separation of monomeric mAb from associated aggregates and impurities was achieved, validating the screening results. Selective desorption also resulted in improved separations on CHT, with 100% yield of pure monomeric mAb as compared to 61% and 79%, respectively, for conventional linear and step gradient operations. This proof of concept study demonstrates selective desorption on CHT as an effective separation technique for the purification of monomeric mAb from associated aggregates and other post‐protein A step impurities in a single process step. Biotechnol. Bioeng. 2011; 108:813–821. © 2010 Wiley Periodicals, Inc.
Is your QSAR/QSPR descriptor real or trash?
Authors: Kiralj Rudolf , Ferreira Márcia M. C.
Published: October 2010

The sign change problem in quantitative structure–activity relationship (QSAR), quantitative structure–property relationship (QSPR) and related studies is the controversy related to the signs of correlation coefficients and regression coefficients of a descriptor in univariate and multivariate regressions, before and after the data split. Among 50 investigated regression models with 227 descriptors extracted from the literature, the sign change problem was shown to have a very high frequency, according to four new criteria proposed in this work for its assessment. The sign change problem can be substantially reduced and even eliminated for a given dataset by statistically based variable selection and by checking for the sign change problem before model validation and interpretation. Knowing the fundamentals of statistics related to the sign change problem, its identification and understanding aid in finding effective means to remedy regression models with this deficiency. Copyright © 2010 John Wiley & Sons, Ltd.
Luminescent Cyclometalated Dialkynylgold(III) Complexes of 2‐Phenylpyridine‐Type Derivatives with Readily Tunable Emission Properties
Authors: Au Vonika Ka‐Man , Wong Keith Man‐Chung , Zhu Nianyong , Yam Vivian Wing‐Wah
Published: October 2010

A novel class of luminescent dialkynylgold(III) complexes containing various phenylpyridine and phenylisoquinoline‐type bidentate ligands has been successfully synthesized and characterized. The structures of some of them have also been determined by X‐ray crystallography. Electrochemical studies demonstrate the presence of a ligand‐centered reduction originating from the cyclometalating C^N ligand, whereas the first oxidation wave is associated with an alkynyl ligand‐centered oxidation. The electronic absorption and photoluminescence properties of the complexes have also been investigated. In dichloromethane solution at room temperature, the low‐energy absorption bands are assigned as the metal‐perturbed π–π* intraligand (IL) transition of the cyclometalating C^N ligand, with mixing of charge‐transfer character from the aryl ring to the pyridine or isoquinoline moieties of the cyclometalating C^N ligand. The low‐energy emission bands of the complexes in fluid solution at room temperature are ascribed to originate from the metal‐perturbed π–π* IL transition of the cyclometalatng C^N ligand. For complex 4 that contains an electron‐rich amino substituent on the alkynyl ligand, a structureless emission band, instead of one with vibronic structures as in the other complexes, was observed, which was assigned as being derived from an excited state of a [π(CCC6H4NH2)→π*(C^N)] ligand‐to‐ligand charge‐transfer (LLCT) transition.
Dual Effect of Halides in the Stille Reaction: In Situ Halide Metathesis and Catalyst Stabilization
Authors: Verbeeck Stefan , Meyers Caroline , Franck Philippe , Jutand Anny , Maes Bert U. W.
Published: October 2010

Halide anions can increase or decrease the transmetallation rate of the Stille reaction through in situ halide metathesis. Although the influence of the halogen present in oxidative addition complexes on the transmetallation rate with organostannanes was already known, the application of in situ halide metathesis to accelerate cross‐coupling reactions with organometallic reagents is not described in the literature yet. In addition a second unprecedented role of halides was discovered. Halide anions stabilize the [Pd0(L)2] catalyst in Stille reactions, by means of [Pd0X(L)2]− formation (X=Cl, I), hereby preventing its leaching from the catalytic cycle. Both arene (iodobenzene) and azaheteroarene (2‐halopyridine, halopyrazine, 2‐halopyrimidine) substrates were used.
Das Periodensystem aus der Haribo®‐Tüte
Authors: Schlicht Harald
Published: October 2010

Mithilfe von Haribo‐Konfekt lässt sich ein anschauliches Modell zur Erläuterung der grundsätzlichen Struktur des Periodensystems der Elemente erarbeiten. Dieses Vorgehen ist in einer 8. Klasse der Realschule (lt. Nds. Kerncurriculum) einsetzbar. Ein Periodensystem aus einer Gummibärentüte? Das klingt interessant und das soll es auch sein, insbesondere für die Schülerinnen und Schüler, die auf den ersten Blick sicherlich keinen Zusammenhang zwischen Spaß (den Süßwaren) und dem „bitteren“ Ernst des Lebens (Chemieunterricht) erkennen werden.
Bromwasser
Authors: Kreher Richard P. , Schmidkunz Heinz
Published: October 2010

Bromwasser ist ein attraktives und elegantes Reagenz für organische Verbindungen mit nucleophiler Reaktivität (Alkene, Cyclo‐ und Polyalkene, Phenole und Lebensmittelfarbstoffe). Die eindrucksvollen Experimente sind für einen interessanten und motivierenden Chemieunterricht an Schulen geeignet.
KEMIE: Kinder Erleben Mit Ihren Eltern Chemie
Authors: Sommer Katrin , Russek Adrian , Kleinhorst Helma
Published: October 2010

Das Projekt KEMIE (Kinder Erleben Mit Ihren Eltern Chemie) ist ein langfristig angelegtes Eltern‐Kind‐Projekt, das sich an Kinder ab der 3. bis einschließlich der 6. Jahrgangsstufe und deren Eltern richtet. Dabei stehen die Eltern ihren Kindern als Experimentier‐ und Lernpartner zur Seite. Die Entwicklung der insgesamt neun Versuchstage, die über einen Zeitraum von Oktober bis Juni stattfinden, basiert auf einem didaktischen Konzept, das die Leitlinien „naturwissenschaftliche Denk‐ und Arbeitsweisen“, „Stoff‐Struktur‐Eigenschaften“ und „Alltagsbezug“ einschließt. Als Veranstaltungsort für das KEMIE‐Projekt wird ein außerschulischer Lernort, nämlich das Alfried Krupp‐Schülerlabor der Ruhr‐Universität Bochum, genutzt. In diesem Beitrag werden das didaktische Konzept und Schwerpunkte eines fachmethodischen Spiralcurriculums exemplarisch vorgestellt sowie erste Ergebnisse zur Annahme des Projektes durch die Teilnehmer präsentiert.
Asborin Inhibits Aldo/Keto Reductase 1A1
Authors: Scholz Matthias , Steinhagen Max , Heiker John T. , Beck‐Sickinger Annette G. , Hey‐Hawkins Evamarie
Published: October 2010

Asborin is the carbaborane analogue of aspirin. Replacement of the phenyl ring in aspirin by ortho‐carbaborane was found to change the pharmacological profile of the compound remarkably. Unlike aspirin, asborin cannot selectively acetylate a single serine residue in the active site of cyclooxygenase, and as a result inhibitory potency is reduced. Activation of the acetyl group and the presence of the hydrophobic and bulky cluster therefore did not meet the requirements for cyclooxygenase inhibition. Both features, however, match perfectly for inhibition of the aldo/keto reductase family. Herein, we describe the identification of aldo/keto reductase (AKR) 1A1 as an enzymatic target of asborin, which is inhibited in the low micromolar range. The detailed mode of inhibition was studied and is discussed with respect to the cluster properties. The results shed light on how ortho‐carbaborane can be used as a drug synthon, as well as on the development of carbaborane‐based inhibitors of other aldo/keto reductases.
Devices to facilitate magic angle studies in peripheral MRI
Authors: Rea Marc , Tse Zion Tsz Ho , Elhawary Haytham , Lamperth Michael , Paley Martyn , Bydder Graeme M. , Young Ian R.
Published: October 2010

Purpose: Four devices are described as variants of a single concept to assist the imaging of tissues with T2 relaxation times substantially influenced by dipolar coupling. The signal levels of such tissues are subjected to “magic angle” effects and determined by their orientation to B0. Methods: The pneumatically actuated devices remotely move patient's anatomy so that the angle of tissues relative to B0 can be easily adjusted within a closed‐bore MRI scanner. Images taken with tissues at various orientations are analyzed to study the dipolar coupling effects. The devices include: a small hand unit, a unit for the Achilles tendon, a 3DOF platform for imaging the knee, and an upper limb unit. Results: Results obtained with all four devices are illustrated, demonstrating their utility to manipulate anatomy in an MRI environment. Conclusion: The successful demonstration of the devices can facilitate a fuller clinical evaluation of magic angle‐related phenomena. © 2010 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 37B: 220–225, 2010.