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The room-temperature photochemical reaction of the tricarbollide anion [nido-7,8,9-C3B8H11]^- (1a) with [CpFe(C6H6)]⁺ proceeds without cluster rearrangement to form the 12-vertex closo-ferratricarbollide 1-Cp-1,2,3,4-FeC3B8H11 (2a, the metal atom is assigned number 1). 2a rearranges to the isomeric complex 1-Cp-1,2,3,5-FeC3B8H11 (2b) at 110 °C and further to 1-Cp-1,2,4,10-FeC3B8H11 (2c) at 165 °C. The reaction of 1a with [Cp*RuCl]4 is accompanied by polyhedral rearrangement giving 1-Cp*-1,2,3,5-RuC3B8H11 (3b). Its further isomerization occurs slowly at room temperature and rapidly at 65 °C to give complex 1-Cp*-1,2,4,10-RuC3B8H11 (3c). Similar reactions of [nido-7,8,10-C3B8H11]^- (1b) with [CpFe(C6H6)]⁺ and [Cp*RuCl]4 afford 2b and 3b, respectively. A diamond-square-diamond mechanism for the 2a → 2b → 2c rearrangement sequence is proposed. The relative stability of isomers 2a−c was estimated by DFT calculations. The constitution of the compounds prepared was determined by multinuclear NMR spectroscopy and mass spectrometry. The structures of 2a, 2b, and 3c were established by X-ray diffraction.

We describe an efficient protocol to effect multisite conjugation reactions to oligomers on solid-phase support. Sequence-specific N-substituted glycine “oligopeptoids” were utilized as substrates for azide−alkyne cycloaddition reactions. Diverse groups, including nucleobases and fluorophores, were conjugated at up to six positions on peptoid side chains with yields ranging from 88 to 96%. This strategy will be broadly applicable for generating polyvalent displays on peptides and other scaffolds, allowing precise control of spacing between the displayed groups.

Background & Aims: Endoscopy is commonly performed to evaluate symptoms of dyspepsia. The aim of this study was to characterize patients who receive endoscopy for dyspepsia and measure predictors of primary endoscopic outcomes, utilizing a large national endoscopic database. Methods: The Clinical Outcomes Research Initiative (CORI) receives endoscopy reports from a network of 74 sites in the United States. Sixty-one percent of reports come from private practice settings. Patients with reflux dyspepsia and nonreflux dyspepsia were identified from January 2000 to June 2002. Patients with dysphagia and known Barrett's esophagus were excluded. Primary endoscopic outcomes included esophageal inflammation and stricture, gastric ulcer, duodenal ulcer, suspected Barrett's esophagus (>=2cm), and suspected esophageal and gastric malignancy. The presence or absence of alarm symptoms (vomiting, weight loss, and evidence of GI blood loss) was determined. Adjusted relative risk (RR) for predicting serious outcomes was calculated in a multivariate model. Results: We received 117,497 endoscopic reports, representing 99,558 unique patients. Dyspepsia, with and without reflux symptoms, accounted for 43% of upper endoscopies. Among dyspeptic patients, 36.5% were younger than 50 years of age without alarm symptoms. Esophageal or gastric malignancy in patients with dyspepsia was associated with increasing age, male sex, Asian race, Native American race, and symptoms of weight loss and vomiting. Suspected Barrett's esophagus (>=2cm) was associated with reflux symptoms, male sex, age, and white race. Ulcers were associated with evidence of bleeding, vomiting, male sex, black race, and Hispanic ethnicity. Conclusions These practice-based data reveal important practice behaviors and outcomes.

Data on the survival of all incident cases collected by population-based cancer registries make it possible to evaluate the overall performance of diagnostic and therapeutic actions on cancer in those populations. EUROCARE-3 is the third round of the EUROCARE project, the largest cancer registry population-based collaborative study on survival in European cancer patients. The EUROCARE-3 study analysed the survival of cancer patients diagnosed from 1990 to 1994 and followed-up to 1999. Sixty-seven cancer registries of 22 European countries characterised by differing health systems participated in the study. This paper includes essays providing brief overviews of the state and evolution of the health systems of the considered countries and comments on the relation between cancer survival in Europe and some European macro-economic and health system indicators, in the 1990s.

Let $ W(D)$ $ f(z) = \sum\nolimits_{n = 0}^\infty {{a_n}{z^n}} $ $ \sum\nolimits_{n = 0}^\infty {\left\vert {{a_n}} \right\vert < + \infty } $ the $ k$ $ \left\{ {{z^{kn}} \cdot f(z)} \right\}_{n = 0}^\infty $ equivalent to the basis $ \left\{ {{z^n}} \right\}_{n = 0}^\infty $ has no set of $ k$ .

In this paper factorization techniques are introduced into the study of tensor product mappings to complete and improve on some results obtained by the author in an earlier paper [Tensor product mappings, Math. Ann. 188 (1970), 1-12. MR 44 #2052]. The main results are as follows: Let $ \alpha $-norm. Then (i) if S is absolutely summing and T is an integral operator then $ S{ \otimes _\alpha }T$ (ii) if S is quasi-nuclear and T is nuclear then $ S{ \otimes _\alpha }$ (iii) if S and T are integral operators then $ S{ \otimes _\alpha }T$ That the results (i) and (ii) are essentially the best possible was shown by examples in the earlier quoted paper. Also, the methods developed in this paper yield a much simpler proof of the main result of the earlier paper.

The purpose of this paper is to give a number of characterizations of reflexive Banach spaces having Schauder bases. We show that a Banach space $ X$ is contained in either $ X$ $ {X^{\ast}}$. It follows that a Banach space with an unconditional basis is reflexive if and only if no basis is of type . It is also shown that a Banach space with a basis is reflexive if and only if every basis converges weakly to zero.

Giving a new proof of a result of Grothendieck, it is shown that a weak operator limit of a bounded net of integral maps is again integral and that every integral map is a weak operator limit of a net of finite dimensional maps which are uniformly bounded in nuclear norm. It is also shown that the subnuclear maps defined by Ruckle are precisely the integral maps. Using this result some questions of Ruckle are answered.

This paper studies the relationship between unitarily invariant crossnorms on the tensor product of Hilbert spaces and the corresponding symmetric sequence spaces. It is shown that problems concerning the behavior of norm ideals of compact operators on Hilbert space can often be treated successfully by translating the problem to one concerned with basis theory (and hence, perhaps, to one more transparent). For example, Schatten has asked for necessary and sufficient conditions that the conjugate space of a minimal norm ideal again be a minimal norm ideal. Using the ideas developed here we give such a characterization.

Let E and F be Banach spaces, $ E \otimes F$ $ E{ \otimes _\alpha }F$ $ E \otimes F$ $ \alpha \geqq \lambda $ is the ``least", and $ \gamma $ $ E{ \otimes _\lambda }F$ $ {E^ \ast }$F and from $ {F^ \ast }$E, take the unit balls in $ {E^ \ast }$ $ {F^ \ast }$F and E, respectively. In §3 we prove that if $ {T_1}:{E_1} \to {E_2}$ $ {T_2}:{F_1} \to {F_2}$ $ {T_1}{ \otimes _\lambda }{T_2}$ $ {T_1}{ \otimes _\lambda }{T_2}$ are also given. Schatten has characterized $ {(E{ \otimes _\alpha }F)^ \ast }$-norm". In §4 we show that a space of operators has such a representation if and only if its unit ball is weak operator compact.

Let X and Y denote Banach spaces with bases $ ({x_i})$, respectively, and let $ X{ \otimes _\varepsilon }Y$ $ X{ \otimes _\pi }Y$ $ \varepsilon $ crossnorms of the algebraic tensor product $ X \otimes Y$ The purpose of this paper is to study the structure of the tensor product spaces $ X{ \otimes _\varepsilon }Y$ $ X{ \otimes _\pi }Y$ $ ({x_i} \otimes {y_j})$ of such bases.

Abstract: Very often experience on virtual conferences is vague: there have been problems with discussion and personal contacts. Also the recognition of papers published “virtually” may be a problem. On the other side, there are clear benefits, too: speed of procedure, no need for travelling, a possibility to extend the discussion, etc. The paper presents methods and procedures in a case where drawbacks could be minimized and a positive experience claims a success.

Let $ E$ be Banach spaces and denote by $ L(E,F)$ the space of all bounded linear operators (resp., all compact operators) from $ E$. In this note the following theorem is proved: If $ E$ are reflexive and one of $ E$ has the approximation property then the following are equivalent: (i) $ L(E,F)$is reflexive, (ii) $ L(E,F) = K(E,F)$ (iii) if $ T \ne 0 \in L(E,F)$ $ \vert\vert T\vert\vert = \vert\vert Tx\vert\vert$ $ x \in E,\vert\vert x\vert\vert = 1$ This result extends a recent result of Ruckle (Proc. Amer. Math. Soc. 34 (1972), 171-174) who showed (i) and (ii) are equivalent when both $ E$ have the approximation property. Moreover the proof suggests strongly that the assumption of the approximation property may be dropped.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.