During mitosis, a single nucleus gives rise to two nuclei that are identical to the parent nucleus. Mitosis consists of a continuous sequence of events that must be carried out once and only once. Two such important events are the disassembly of the nuclear envelope (NE) during the first stages of mitosis, and its accurate reassembly during the last stages of mitosis. NE breakdown (NEBD) is initiated when maturation-promoting factor (MPF) enters the nucleus and starts phosphorylating nuclear pore complexes (NPCs) and nuclear lamina proteins, followed by NPC and lamina breakdown. Nuclear reassembly starts when nuclear membranes assemble onto the chromatin. This article focuses on the different models of NEBD and reassembly with emphasis on recent data.
Thin films with enantioselective properties for electrochemically active chiral probes were developed. Enantioselectivity was accomplished via molecular imprinting. The films were fabricated through the sol-gel technique and were spin-coated on ITO electrodes. The chiral selectivity recognition was detected using two enantiomer pairs: D- and L-3,4-dihydroxyphenylalanine (D- and L-dopa) and (R)- and (S)-N,N'-dimethylferrocenylethylamine [(R)-Fc and (S)-Fc]. A defined chiral cavity was obtained by selection of functional monomers that interact with the template molecule, followed by its removal. Chiral selection properties were measured by cyclic voltammetry and square wave voltammetry. For both template molecules, very good chiral recognition was revealed by electrochemical measurement. The nonspecific adsorption measured for reference nonimprinted films was negligible (less than 5%). Dopa imprinted films revealed both high sensitivity, by the detection of 1 nM (0.2 ppb) concentration, and excellent selectivity, when challenged with a series of catechol derivatives. Fc-imprinted films were able to detect ca. 2 ppm of the target molecule, with very good enantioselectivity and low nonspecific adsorption. To our knowledge, this is the first report of successful molecular imprinting of a ferrocene derivative.[on SciFinder (R)]
Thin films with enantioselective properties for electrochem. active chiral probes were developed. Enantioselectivity was accomplished via mol. imprinting. The films were fabricated through the sol-gel technique and were spin-coated on ITO electrodes. The chiral selectivity recognition was detected using two enantiomer pairs: D- and L-3,4-dihydroxyphenylalanine (D- and L-dopa) and (R)- and (S)-N,N'-dimethylferrocenylethylamine [(R)-Fc and (S)-Fc]. A defined chiral cavity was obtained by selection of functional monomers that interact with the template mol., followed by its removal. Chiral selection properties were measured by cyclic voltammetry and square wave voltammetry. For both template mols., very good chiral recognition was revealed by electrochem. measurement. The nonspecific adsorption measured for ref. nonimprinted films was negligible (<5%). Dopa imprinted films revealed both high sensitivity, by the detection of 1 nM (0.2 ppb) concn., and excellent selectivity, when challenged with catechol derivs. Fc-imprinted films were able to detect ∼2 ppm of the target mol., with very good enantioselectivity and low nonspecific adsorption. To the authors' knowledge, this is the 1st report of successful mol. imprinting of a ferrocene deriv. [on SciFinder(R)]
OBJECTIVES: To describe the clinical, genetic, and electrophysiologic characteristics of a new PAS-domain HERG mutation (M124R) that has been identified in a single large Jewish family with Long QT syndrome (LQTS).
BACKGROUND: Many previously reported HERG mutations causing LQTS are located either in the C-terminus, or in the pore region. Relatively fewer clinical data are available on N-terminus (PAS-domain) mutation carriers.
METHODS: Clinical data were available in 76 family members (aged 1-93 years, 69 alive) over 18 years of follow-up, while electrocardiographic data were available in 57, and genetic data in 45 family members. Cellular electrophysiology was assessed in transfected Chinese Hamster Ovary (CHO) cells using the whole-cell patch-clamp technique.
RESULTS: Thirty-six family members were phenotypically categorized as nonaffected, 3 as equivocal, and 20 as affected. Mean QTc was 410+/-23, 440+/-10, and 498+/-41 ms, respectively, in these three subgroups. Eight out of 20 affected family members were symptomatic: five had only syncope, two had aborted cardiac arrest, and one sudden death. Genetic analyses identified the M124R point mutation in all affected members tested (n=16), while all those tested with nonaffected (n=26) and equivocal (n=3) phenotype did not carry the mutation. The M124R mutation reduced the HERG tail-current density by 65%, significantly accelerated the deactivation kinetics, and caused a negative shift in the voltage dependence of activation.
CONCLUSIONS: A new PAS-domain HERG mutation (M124R) was identified as causing LQTS in a large Jewish family, with high penetrance and frequent disease-related symptoms. This mutation markedly decreased the tail-current density and accelerated the deactivation kinetics of the HERG channel in transfected CHO cells.
Robust arrays of ordered nanoparticles (see Figure and cover) have been created by combining two self‐assembly strategies: microphase separation of block copolymers and coordination chemistry. Thin films of a microphase‐separated block copolymer serve as templates for patterning of terpyridine‐functionalized gold nanoparticles. Subsequent treatment with iron salts crosslinks the patterned nanoparticles via the formation of iron–terpyridine complexes.
We derive an exact representation of the exchange-correlation energy within density functional theory (DFT) which spawns a class of approximations leading to correct long-range asymptotic behavior. Using a simple approximation, we develop an electronic structure theory that combines a new local correlation energy (based on Monte Carlo calculations applied to the homogeneous electron gas) and a combination of local and explicit long-ranged exchange. The theory is applied to several first-row atoms and diatomic molecules where encouraging results are obtained: good description of the chemical bond at the same time allowing for bound anions, reasonably accurate affinity energies, and correct polarizability of an elongated hydrogen chain. Further stringent tests of DFT are passed, concerning ionization potential and charge distribution under large bias
For many years, political communication scholars believed that political campaigns have only minimal effects on the public and subsequently on election results. The main justification for this minimal effects hypothesis was the fact that scholars found it impossible to measure and identify substantial persuasion effects that are the outcome of a campaign. But for more than a decade now, scholars who study political campaigns hypothesize that political campaigns have a strong persuasive effect on the voters. They argue that such persuasive effects could hardly be measured because most major political campaigns are relatively balanced, and therefore have a canceling-out effect. They hypothesize that it would be possible to measure the effects of persuasion in an extremely asymmetric campaign, but they hardly find any such major campaigns in modern times. The campaign over Sharon’s disengagement plan in Israel was extremely imbalanced and is therefore an interesting and important example
The article focuses on the detection of minimal effects in imbalanced political campaigns. The minimal effects hypothesis is slowly loosing its paradigmatic position in the field of political communication. Among the reasons for this paradigmatic change are the recognition in importance of the indirect cognitive effects of the campaign. These include findings on the educational role of campaigns, campaign effects on voter turnout and the short-term effects of campaign events.
