cssi/SciSciGPT-SciSciNet huggingface dataset:
Migration and differentiation of shepherd's crook cells in the optic tectum of the chick embryo

Abstract Shepherd's crook cells are a class of neurons with perikarya in the intermediate tectal layers, single or multiple basal dendrites, and long apical dendrites from which the axon arises in the form of a shepherd's crook. The axon distinguishes this neuron from all other types, even at early developmental stages. Migration and differentiation of these cells were followed in rapid Golgi preparations from a series of staged embryos and chicks. Since the axon is the first definitive process to appear, even before the cell body completes its migration, it was possible to identify this cell type early in development and to reconstruct certain morphogenetic events that characterize neurogenesis in this class of cells. The postmitotic, migratory neuroblast extends from the outer border of the matrix zone and, by its external, leading process, runs radially through the deep fiber layer into the marginal zone. While the perikaryon is still within the deep fiber layer, the axon appears on the external process in the form of a crook. The crook provides a fixed point of reference within the presumptive intermediate tectal layers during succeeding stages of development. Subsequently, the perikaryon must move up or through its own external process to reach its final location in the intermediate tectal layers. As a result of this mode of migration there often remains a long, thin tail of the trailing, internal process extending back into the deep fiber layer. The definitive apical and basal dendrites appear to develop, respectively, from the remaining portions of the external and internal processes. In the development of the shepherd's crook cell there is a strict sequence of morphogenetic changes. Hence, specificity in the nervous system manifests itself not only in the types of neurons formed and their connections, but also in the assembly process itself. However, the exact sequence of the transitions differs for different types of neurons. In the case of the shepherd's crook cell, a leading process grows into the mantle zone, followed by the outgrowth of the axon, migration of the perikaryon, and, finally, differentiation of the dendrites. The factors that initiate axonal and dendritic growth seem to be independent of perikaryal location. The perikaryon continues to migrate after axonal outgrowth but never reaches the origin of the axon. We conclude that the migration of the shepherd's crook cell takes place by perikaryal translocation through an external, leading process. In the light of these findings, we suggest that the progress of a cell's migration can be analyzed with reference to three events: a change in the length of the leading process, a change in the length of the trailing process, and a change in the position of the perikaryon within the cerebral wall. Differences in the rates at which these three events occur could explain the variety of morphological forms assumed by migratory neuroblasts in different parts of the brain.
Microinjection of morphine into the rat medullary dorsal horn produces a dose-dependent increase in facial scratching

It has been proposed that opioids act at the level of the medulla to produce facial pruritus. Supporting this hypothesis, microinjection of mu-opioid receptor agonists into the medullary dorsal horn (MDH; trigeminal subnucleus caudalis) of monkeys produces facial scratching behavior. The present study sought to establish a rodent model of opioid-induced facial pruritus. To this end, morphine (0.1, 0.3 or 1.0 micrograms/0.2 microliter) or saline (0.2 microliter) was unilaterally microinjected into the MDH of male Sprague-Dawley rats. Behavior for the 20 min preceding and the 80 min after this microinjection was videotaped. Morphine produced dose-dependent increases in facial scratching behavior ipsilateral to the microinjections with the peak effect at 30-40 min after microinjection. Facial scratching continued for the entire 80 min post-microinjection test period. Morphine also produced a lesser degree of facial scratching contralateral to the microinjections. Increases in facial scratching ipsilateral to the microinjection of 0.3 microgram morphine into the MDH were attenuated by 0.4 mg/kg s.c. naloxone. These findings support the hypothesis that the MDH is a critical site of action of opioid agonists in producing facial pruritus.
Cavity QED with optically transported atoms

Ultracold $^{87}\mathrm{Rb}\phantom{\rule{0.3em}{0ex}}\text{atoms}$ are delivered into a high-finesse optical microcavity using a translating optical lattice trap and detected via the cavity field. The atoms are loaded into an optical lattice from a magneto-optic trap and transported $1.5\phantom{\rule{0.3em}{0ex}}\mathrm{cm}$ into the cavity. Our cavity satisfies the strong-coupling requirements for a single intracavity atom, thus permitting real-time observation of single atoms transported into the cavity. This transport scheme enables us to vary the number of intracavity atoms from $1\phantom{\rule{0.5em}{0ex}}\text{to}\phantom{\rule{0.5em}{0ex}}g100$ corresponding to a maximum atomic cooperativity parameter of 5400, the highest value ever achieved in an atom-cavity system. When many atoms are loaded into the cavity, optical bistability is directly measured in real-time cavity transmission.
Influence of a dedicated paediatric cardiac intensive care unit on patient outcomes

Background: The impact of a designated intensive care unit (ICU) for postoperative cardiac care in children is not clear. In our hospital (in the USA), we started a new Paediatric Cardiac Surgery programme 5 years ago, in September 2004. During the first 2 years of the programme, postoperative care was accomplished within the general paediatric ICU (PICU or c-ICU). Subsequently, in September 2006, a dedicated cardiac ICU (d-ICU) was established. We looked at our experience during these two periods to determine whether the designation of a separate ICU affected outcomes for these children. Design and Methods: We obtained Institutional Review Board (IRB) approval to review the medical records for all postoperative cardiac admissions to the ICU during the first 4 years of the programme (September 2004–September 2008). Variables collected included age, gender, diagnosis, type of cardiac surgery, Risk Adjustment for Congenital Cardiac Surgery, version 1 (RACHS-1) classification, ventilator use, hospital stay, invasive line infections, ventilator-related infections, wound infections, need for cardiopulmonary support, return to the operating room, re-exploration of the chest, delayed sternal closure, accidental extubations, re-intubation and mortality rates. These variables were summed and compared for the combined PICU and the dedicated paediatric cardiac ICU. Results: There were 199 cases performed in the first 2 years compared with 244 in the following 2 years. We saw a statistically insignificant increase in the number and complexity of cases during the second period (p = 0·08). However, morbidity declined as evidenced by the decrease in wound infection (p < 0·001) and need for chest re-exploration (p < 0·001). In addition, mortality declined from 7 of 199 (3·5%) to 2 of 244 (0·8%). p < 0·04 and less children required resuscitation (p < 0·01). Conclusions: We believe the designation of a specific area for postoperative cardiac care was instrumental in the growth and development of our cardiac programme. This rapid change accomplished several crucial elements that lead to accelerated improvement in patient care and a decline in morbidity and mortality.
Communication: On nucleation statistics in small systems

Non-stationary random formation of stable nuclei from a small metastable system is considered. Distribution of waiting times to observe the first nucleus is examined, and it is shown that the steady-state nucleation rate is given by inverse of the standard deviation, which is independent of the post-critical size n where the nucleus is detected. The mean time, on the other hand, is n-sensitive and contains additional information on transient nucleation and growth effects. The method is applied to Monte Carlo data on nucleation in a cold two-dimensional Ising ferromagnet with Metropolis dynamics, where nucleation rates obtained earlier from low-temperature cluster expansions can provide a strict independent test.
Characterization of 5-Chloro-5-Deoxy-D-Ribose-1-Dehydrogenase in Chloroethylmalonyl-Coenzyme A Biosynthesis: Substrate and Reaction Profiling

SalM is a short-chain dehydrogenase/reductase enzyme from the marine actinomycete Salinispora tropica that is involved in the biosynthesis of chloroethylmalonyl-CoA, a novel halogenated polyketide synthase extender unit of the proteasome inhibitor salinosporamide A. SalM was heterologously overexpressed in Escherichia coli and characterized in vitro for its substrate specificity, kinetics, and reaction profile. A sensitive real-time 13C NMR assay was developed to visualize the oxidation of 5-chloro-5-deoxy-d-ribose to 5-chloro-5-deoxy-d-ribono-γ-lactone in an NAD+-dependent reaction, followed by spontaneous lactone hydrolysis to 5-chloro-5-deoxy-d-ribonate. Although short-chain dehydrogenase/reductase enzymes are widely regarded as metal-independent, a strong divalent metal cation dependence for Mg2+, Ca2+, or Mn2+ was observed with SalM. Oxidative activity was also measured with the alternative substrates d-erythrose and d-ribose, making SalM the first reported stereospecific non-phosphorylative ribose 1-dehydrogenase.
Robust numerical simulation of porosity evolution in chemical vapor infiltration III: three space dimension

Chemical vapor infiltration (CVI) process is an important technology to fabricate ceramic matrix composites (CMC's). In this paper, a three-dimension numerical model is presented to describe pore microstructure evolution during the CVI process. We extend the two-dimension model proposed in [S. Jin, X.L. Wang, T.L. Starr, J. Mater. Res. 14 (1999) 3829; S. Jin. X.L. Wang, T.L. Starr, X.F. Chen, J. Comp. Phys. 162 (2000) 467], where the fiber surface is modeled as an evolving interface, to the three space dimension. The 3D method keeps all the virtue of the 2D model: robust numerical capturing of topological changes of the interface such as the merging, and fast detection of the inaccessible pores. For models in the kinetic limit, where the moving speed of the interface is constant, some numerical examples are presented to show that this three-dimension model will effectively track the change of porosity, close-off time, location and shape of all pores.
Automated stopped-flow analyser in clinical chemistry: determination of albumin with bromcresol green and purple.

Abstract We describe an adaptation of a microcomputer-controlled stopped-flow analyzer for automated analysis of albumin in serum. The immediate reaction between bromcresol green or purple and albumin is used to develop a routine procedure with 12 s reaction time. The approach shows excellent linearity to 68 g/l, good sensitivity, a relative SD of
Linear release nanoparticle devices for advanced targeted cancer therapies with increased efficacy

The cross-linked supramolecular structure of prepared polyester based nanoparticles enable increased and efficient small molecule drug loading after nanoparticle formation and post-modification with targeting peptides via thiol-ene ‘click’ chemistry. It could be demonstrated that the drug loading does not influence the structural integrity of the particle and its diameter was not significantly changed. A prolonged linear release profile of the drug without the typical ‘burst effect’ was observed in emulsified particles and mirrored the linear degradation profile of the investigated particles, which are critical properties for controlled and predictable pharmacokinetics in cancer therapies. Furthermore, the final peptide-targeted and drug-loaded particles were found to be readily dispersed in buffer or water, and with the confirmed biocompatibility, these novel and adjustable drug delivery systems are promising vectors for the treatment of various cancers.
Formation of Polycyanoacrylate-Silica Nanocomposites by Chemical Vapor Deposition of Cyanoacrylates on Aerogels

Here, we report the first CVD reinforcement of silica aerogels using cyanoacrylates to create a silica-polycyanoacrylate nanocomposite. Deposition is fast and homogeneous through monolithic aerogels. The nanocomposite results in a 32× improvement over native silica aerogels while not diminishing the aerogels attractive physical properties.
STRATEGIC POSITIONING OR INSTITUTIONAL COERCION? THE STRUCTURE OF GOVERNING BOARDS

The strategic management perspective suggests that organizations structure their governing boards to complement the strategic goals of the organization. In contrast, the institutionalization perspective holds that organizations structure their governing boards to respond to institutional pressures in their task environment. Regardless of which perspective is followed, three structural dimensions of governing boards are expected to be affected: size, diversity of composition, and medical staff representation. A study was conducted to relate the institutional requirements and strategies of acute care hospitals to the structural characteristics of their boards of directors. Results indicated that, after controlling for organizational size and membership in a multihospital system, the governing board structure of 109 acute care hospitals varied significantly both as a function of their overall business strategy and as a function of institutional linkages. However, the proportion of the total variance in board structure accounted for by strategy variables was approximately twice as much as that accounted for by institutional variables.
Activity-dependent Synaptic Wnt Release Regulates Hippocampal Long Term Potentiation

Abstract Wnts are important for various developmental and oncogenic processes. Here we show that Wnt signaling functions at synapses in hippocampal neurons. Tetanic stimulations induce N-methyl-d-aspartate receptor-dependent synaptic Wnt3a release, nuclear β-catenin accumulations, and the activation of Wnt target genes. Suppression of Wnt signaling impairs long term potentiation. Conversely, activation of Wnt signaling facilitates long term potentiation. These findings suggest that Wnt signaling plays a critical role in regulating synaptic plasticity.
Nicotine and lung cancer

Tobacco use in cancer patients is associated with increased cancer treatment failure and decreased survival. Nicotine is one of over 7,000 compounds in tobacco smoke and nicotine is the principal chemical associated with addiction. The purpose of this article is to review the tumor promoting activities of nicotine. Nicotine and its metabolites can promote tumor growth through increased proliferation, angiogenesis, migration, invasion, epithelial to mesenchymal transition, and stimulation of autocrine loops associated with tumor growth. Furthermore, nicotine can decrease the biologic effectiveness of conventional cancer treatments such as chemotherapy and radiotherapy. Common mechanisms appear to involve activation of nicotinic acetylcholine receptors and beta-adrenergic receptors leading to downstream activation of parallel signal transduction pathways that facilitate tumor progression and resistance to treatment. Data suggest that nicotine may be an important mechanism by which tobacco promotes tumor development, progression, and resistance to cancer treatment.
Narrative Development in Monolingual Spanish-Speaking Preschool Children

Research Findings: The purpose of this study was to describe differences in the narratives produced by 3-, 4-, and 5- year old Spanish-speaking (SS) children. Narrative productions of 104 typically developing children were collected using a story-retelling task and coded using the Index of Narrative Complexity. The results of this study indicate that 3-year-old SS children produced stories containing characters and actions. Four-year-old SS children’s stories were characterized by the use of characters, actions, and internal responses. Five-year-old SS children retold stories containing characters, settings, initiating events, actions, internal responses, formulaic markers, temporal markers, and knowledge of dialogue. Practice: Developmental information to assist educators working with SS children.
Colin Gray, Strategic Studies and Public Policy: American Experiences, (The University Press of Kentucky Lexington, Kentucky, 1982) $19.50.

(1984). Colin Gray, Strategic Studies and Public Policy: American Experiences, (The University Press of Kentucky Lexington, Kentucky, 1982) $19.50. Political Science: Vol. 36, No. 2, pp. 187-188.
Clinical Usefulness of Haptoglobin Levels to Evaluate Hemolysis in Recently Transfused Patients

Introduction. Haptoglobin binds the globin portion of free hemoglobin. Serum haptoglobin measurement is used as a laboratory marker for the diagnosis of hemolytic anemia. Since stored blood contains free hemoglobin, transfusion may affect haptoglobin levels. Study Objectives. The aim of the study was to evaluate whether serum haptoglobin could be measured to assess hemolysis in recently transfused patients. Patients and Methods. Twenty-one patients, receiving more than one unit of packed red blood cells (PRBCs) for presumed nonhemolytic indications, were enrolled. Serum haptoglobin levels were recorded before, immediately after, and 24 and 48 hours after transfusion. Observations and Results. Analysis of variance with a repeated measures was used to examine the serum haptoglobin levels at different time periods and no significant difference was found (P = .28). Conclusion. The results suggest that serum haptoglobin can be used in the diagnosis of hemolysis in patients receiving multiple units of PRBC.
An Alternant Method to the Traditional NASA Hindlimb Unloading Model in Mice

The Morey-Holton hindlimb unloading (HU) method is a widely accepted National Aeronautics and Space Administration (NASA) ground-based model for studying disuse-atrophy in rodents. Our study evaluated an alternant method to the gold-standard Morey-Holton HU tail-traction technique in mice. Fifty-four female mice (4-8 mo.) were HU for 14 days (n=34) or 28 days (n=20). Recovery from HU was assessed after 3 days of normal cage ambulation following HU (n=22). Aged matched mice (n=76) served as weight-bearing controls. Prior to HU a tail ring was formed with a 2-0 sterile surgical steel wire that was passed through the 5(th), 6(th), or 7(th) inter-vertebral disc space and shaped into a ring from which the mice were suspended. Vertebral location for the tail-ring was selected to appropriately balance animal body weight without interfering with defecation. We determined the success of this novel HU technique by assessing body weight before and after HU, degree of soleus atrophy, and adrenal mass following HU. Body weight of the mice prior to HU (24.3 ± 2.9g) did not significantly decline immediately after 14d of HU (22.7 ± 1.9g), 28d of HU (21.3 + 2.1g) or after 3 days recovery (24.0 ± 1.8g). Soleus muscle mass significantly declined (-39.1%, and -46.6%) following HU for 14 days and 28 days respectively (p<0.001). Following 3 days of recovery soleus mass significantly increased to 74% of control values. Adrenal weights of HU mice were not different compared to control mice. The success of our novel HU method is evidenced by the maintenance of animal body weight, comparable adrenal gland weights, and soleus atrophy following HU, corresponding to expected literature values. The primary advantages of this HU method include: 1) ease of tail examination during suspension; 2) decreased likelihood of cyanotic, inflamed, and/or necrotic tails frequently observed with tail-taping and HU; 3) no possibility of mice chewing the traction tape and coming out of the suspension apparatus; and 4) rapid recovery and normal cage activity immediately after HU.
Silicon-based bridge wire micro-chip initiators for bismuth oxide?aluminum nanothermite

We present a micro-manufacturing process for fabricating silicon-based bridge wire micro-chip initiators with the capacity to liberate joules of chemical energy at the expense of micro joules of input electrical energy. The micro-chip initiators are assembled with an open material reservoir utilizing a novel 47 °C melting point solder alloy bonding procedure and integrated with a bismuth oxide–aluminum nanothermite energetic composite. The electro-thermal conversion efficiency of the initiators is enhanced by the use of a nanoporous silicon bed which impedes thermal coupling between the bridge wire and bulk silicon substrate while maintaining the structural integrity of the device. Electrical behaviors of the ignition elements are investigated to extract minimum input power and energy requirements of 382.4 mW and 26.51 µJ, respectively, both in the absence and presence of an injected bismuth oxide–aluminum nanothermite composition. Programmed combustion of bismuth oxide–aluminum nanothermite housed within these initiators is demonstrated with a success rate of 100% over a 30 to 80 µJ range of firing energies and ignition response times of less than 2 µs are achieved in the high input power operation regime. The micro-initiators reported here are intended for use in miniaturized actuation technologies.
Sex-specific relationships between adverse childhood experiences and chronic obstructive pulmonary disease in five states.

Purpose Adverse childhood experiences (ACEs) before age 18 have been repeatedly associated with several chronic diseases in adulthood such as depression, heart disease, cancer, diabetes, and stroke. We examined sex-specific relationships between individual ACEs and the number of ACEs with chronic obstructive pulmonary disease (COPD) in the general population. Materials and methods Data from 26,546 women and 19,015 men aged ≥18 years in five states of the 2011 Behavioral Risk Factor Surveillance System were analyzed. We used log-linear regression to estimate prevalence ratios (PRs) and their corresponding 95% confidence intervals (CIs) for the relationship of eight ACEs with COPD after adjustment for age group, race/ethnicity, marital status, educational attainment, employment, asthma history, health insurance coverage, and smoking status. Results Some 63.8% of women and 62.2% of men reported ≥1 ACE. COPD was reported by 4.9% of women and 4.0% of men. In women, but not in men, there was a higher likelihood of COPD associated with verbal abuse (PR =1.30, 95% CI: 1.05, 1.61), sexual abuse (PR =1.69, 95% CI: 1.36, 2.10), living with a substance abusing household member (PR =1.49, 95% CI: 1.23, 1.81), witnessing domestic violence (PR =1.40, 95% CI: 1.14, 1.72), and parental separation/divorce (PR =1.47, 95% CI: 1.21, 1.80) during childhood compared to those with no individual ACEs. Reporting ≥5 ACEs (PR =2.08, 95% CI: 1.55, 2.80) compared to none was associated with a higher likelihood of COPD among women only. Conclusion ACEs are related to COPD, especially among women. These findings underscore the need for further research that examines sex-specific differences and the possible mechanisms linking ACEs and COPD. This work adds to a growing body of research suggesting that ACEs may contribute to health problems later in life and suggesting a need for program and policy solutions.
Sensible method for updating motif instances in an increased biological network.

Abstract A network motif is defined as an over-represented subgraph pattern in a network. Network motif based techniques have been widely applied in analyses of biological networks such as transcription regulation networks (TRNs), protein–protein interaction networks (PPIs), and metabolic networks. The detection of network motifs involves the computationally expensive enumeration of subgraphs, NP-complete graph isomorphism testing, and significance testing through the generation of many random graphs to determine the statistical uniqueness of a given subgraph. These computational obstacles make network motif analysis unfeasible for many real-world applications. We observe that the fast growth of biotechnology has led to the rapid accretion of molecules (vertices) and interactions (edges) to existing biological network databases. Even with a small percentage of additions, revised networks can have a large number of differing motif instances. Currently, no existing algorithms recalculate motif instances in ‘updated’ networks in a practical manner. In this paper, we introduce a sensible method for efficiently recalculating motif instances by performing motif enumeration from only updated vertices and edges. Preliminary experimental results indicate that our method greatly reduces computational time by eliminating the repeated enumeration of overlapped subgraph instances detected in earlier versions of the network. The software program implementing this algorithm, defined as SUNMI (Sensible Update of Network Motif Instances), is currently a stand-alone java program and we plan to upgrade it as a web-interactive program that will be available through http://faculty.washington.edu/kimw6/research.htm in near future. Meanwhile it is recommended to contact authors to obtain the stand-alone SUNMI program.
Lateral migration mechanisms in capillary hydrodynamic chromatography

Abstract In all chromatographic systems that achieve separation of colloidal particles based on the particles' hydrodynamic behavior, there are partitioning mechanisms that promote lateral migration of particles across solvent streamlines. In this work, solvent inertia and particle electrostatics are incorporated in Brenner & Gaydos' general diffusive transport theory for particles and solvent flowing in a capillary, yielding the mean axial velocity of particles as a function of particle size. A comparison is made with capillary hydrodynamic chromatography results. The lateral migration of small particles is primarily due to diffusion, while large particles are focused by the inertial force at one equilibrium radial position, as observed in “tubular pinch” experiments. The transition from diffusion- to inertia-controlled lateral migration can be tuned to specific particle size ranges through variation of solvent ionic strength, flowrate and capillary radius. Poor prediction of the separation behavior of large particles is attributed to inaccuracy in the calculation of the inertial radial velocity, suggesting the need for further theoretical analysis and experimental study of inertial migration.
Invariant fundamental solutions and solvability for symmetric spaces of type GC/GR with only one conjugacy class of Cartan subspaces

and we show that this condition implies that F(D) has a fundamental solution on A, and hence, as an application of Theorem 5, that D is solvable, see Theorem 7. Notation Let G be a reductive complex connected Lie group with Lie algebra g, and let H be a real form of G with Lie algebra ~. Let cr denote the conjugation of 1~ relative to b and let also cr denote the involution of G whose differential is a, then H is the open connected subgroup of G ~, the fixpoint set of cr in G. The space
Observed patient compliance with a structured outpatient bladder retraining program.

Abstract Objective: Our purpose was to determine patient compliance with a telephone-based retraining program. Study Design: This was a retrospective study of 123 women with urinary urgency or urge incontinence who were offered bladder retraining with facsimile machine submission of a retraining diary and weekly telephone feedback. Results: Completion was defined as having ≥4 follow-up sessions and ≥6 weeks of retraining. Seventy-one percent (87/123) began the retraining program; 63% (55/87) of them completed it, for an overall compliance rate of 45% (55/123). When we compared those who completed retraining with those who started but did not complete it, only concurrent use of pharmacologic therapy was significantly different (87% vs 53%, respectively; P Conclusions: A total of 55% of women to whom telephone-based bladder retraining was recommended either never started or were noncompliant with the treatment. Bladder retraining success in the "real world" may be substantially lower than that described in well-funded labor-intensive clinical trials. (Am J Obstet Gynecol 1999;181:1392-4.)
The acquisition and maintenance of cytolytic activity by CD4+ murine T-lymphocyte clones.

Abstract The class II MHC antigen-specific CTL clones described in this report lose lytic activity when grown in exogenous rIL-2, but regain lytic activity when rIL-2 is removed from the culture medium. Using this cell model, we have investigated the metabolic activities (i.e., DNA, RNA, and protein synthesis) required for CTL to acquire or down-regulate lytic activity. DNA synthesis inhibitors (hydroxyurea and cytosine-arabinoside) and irradiation did not prevent CTL from gaining lytic activity. However, when protein or RNA synthesis was inhibited, these CTL could no longer acquire lytic activity. Furthermore, evidence showed that continuous RNA and protein syntheses were essential for CTL to exert their lytic function. Studies on cell surface antigen expression of CD3, CD4, Thy-1, and LFA-1 revealed no significant difference of antigen expression between a cloned CTL in its lytic and nonlytic states. Our data suggested that the synthesis of certain proteins and their encoded mRNA are essential for CTL to exert its lytic function, and these proteins are not the cell surface antigens involved in CTL-target recognition or binding. Data also indicated that a granule enzyme, serine-esterase, was not involved in the expression of lytic activity in these CTL clones.
A 207Pb NMR study of the adducts of triphenyllead chloride and diphenyllead dichloride

207Pb NMR spectra were used to determine the structure of adducts of triphenyllead chloride and diphenyllead dichloride in CH2Cl2 and CH3CN. The bases included several phosphorus donors, such as tributylphosphine, oxygen donors, such as tributylphosphine oxide, and nitrogen donors, such as pyridine. A number of bidentate bases were also studied. The 207Pb spectra indicate that rapid exchange occurs in the adducts, even at temperatures of −90 °C. The magnitude of the shift relative to the lead acid indicates that all of the bases, including the bidentate bases, form five-coordinate adducts with triphenyllead chloride. Diphenyllead dichloride forms six-coordinate adducts, except for the adduct with tributylphosphine, which is five-coordinate. This is the first report of a five-coordinate adduct of diphenyllead dichloride. Copyright © 2003 John Wiley & Sons, Ltd.
A Hormone Response Element in the Human Apolipoprotein CIII (ApoCIII) Enhancer Is Essential for Intestinal Expression of the ApoA-I and ApoCIII Genes and Contributes to the Hepatic Expression of the Two Linked Genes in Transgenic Mice

We have generated transgenic mice carrying wild-type promoters of the human apolipoprotein A-I (apoA-I)-apoCIII gene cluster or promoters mutated in their hormone response elements. The wild-type cluster directed high levels of apoA-I gene expression in liver and intestine, moderate expression in kidney, and low to minimal expression in other tissues. It also directed high levels of chloramphenicol acetyltransferase (CAT) expression (used as a reporter for the apoCIII gene) in liver, low levels in intestine and kidney, and no expression in other tissues. Mutations in the apoCIII promoter and enhancer abolished the intestinal and renal expression of the apoA-I gene, reduced hepatic apoA-I expression by 80%, and abolished CAT expression in all tissues. A similar pattern of expression was obtained by mutations in the apoCIII enhancer alone. Mutations in the proximal apoA-I promoter reduced by 85% hepatic and intestinal apoA-I expression and did not affect CAT expression. The findings suggest that a hormone response element within the apoCIII enhancer is essential for intestinal and renal expression of apoA-I and apoCIII genes and also enhances hepatic expression. The hormone response elements of the proximal apoA-I promoter or the apoCIII enhancer can promote independently low levels of hepatic and intestinal expression of the apoA-I gene in vivo.
Structural heterogeneity promotes triggered activity, reflection and arrhythmogenesis in cardiomyocyte monolayers

Patients with structural heart disease are predisposed to arrhythmias by incompletely understood mechanisms. We hypothesized that tissue expansions promote source-to-sink mismatch leading to early after-depolarizations (EADs) and reflection of impulses in monolayers of well-polarized neonatal rat ventricular cardiomyocytes.We traced electrical propagation optically in patterned monolayers consisting of two wide regions connected by a thin isthmus.Structural heterogeneities provided a substrate for EADs, retrograde propagation along the same pathway (reflection) and reentry initiation. Reflection always originated during the action potential (AP) plateau at the distal expansion. To determine whether increased sodium current(INa) would promote EADs, we employed adenoviral transfer of Nav1.5 (Ad-Nav1.5). Compared with uninfected and adenoviral expression of green fluorescent protein (Ad-GFP; viral control),Ad-Nav1.5 significantly increased Nav1.5 protein expression, peak and persistent INa density, A Pupstroke velocity, AP duration, conduction velocity and EAD incidence, as well as reflection incidence (29.2%, n =48 vs. uninfected, 9.4%, n =64; and Ad-GFP, 4.8%, n =21). Likewise,the persistent INa agonist veratridine (0.05–3 μM) prolonged the AP, leading to EADs and reflection. Reflection led to functional reentry distally and bigeminal and trigeminal rhythms proximally. Reflection was rare in the absence of structural heterogeneities.Computer simulations demonstrated the importance of persistent INa in triggering reflection and predicted that the gradient between the depolarizing cells at the distal expansion and the repolarizing cells within the isthmus enabled retrograde flow of depolarizing electrotonic current to trigger EADs and reflection. A combination of a substrate (structural heterogeneity) and a trigger (increased persistent INa and EADs) promotes reflection and arrhythmogenesis.
Skeletal Muscle Ischemia-Reperfusion Injury: A Review of Endothelial Cell-Leukocyte Interactions

Ischemia-reperfusion injury remains a difficult problem facing vascular surgeons because of its associated high morbidity and mortality. The basis for tissue injury during ischemia depends on depletion of tissue oxygen and energy substrates. Cell injury, as documented cellular edema and lysosomal degranulation, begins after only 30 min of ischemia. Irreversible cellular changes occur after 4-6 h of skeletal muscle ischemia. Following acute arterial occlusion, the restoration of blood flow heralds the onset of biochemical events, forming the basis of what is known as the reperfusion syndrome. This tissue injury is maximal in areas with the greatest blood flow during reperfusion. Endothelium-leukocyte interactions play an important role in ischemia-reperfusion injury. Both endothelial and white blood cells have the biochemical machinery and capacity to generate molecular signals, to express adhesion proteins, and to produce toxic metabolic by-products. Since the microcirculatory changes in ischemia-reperfusion injury parallel those seen in inflammation, the leukocyte-endothelial interaction can explain many of the reactions associated with the early phases of ischemia-reperfusion injury.
SMRP: fast restoration of multicast sessions from persistent failures

The growing reliance of networked applications on timely and reliable data transfer requires the underlying networking infrastructure to provide adequate services even in the presence of "persistent" failures (e.g., broken links/routers). It is much more difficult to meet this requirement for multicast sessions than for unicast communications because any on-tree component failure may often cause simultaneous service disruptions to multiple receivers. This paper presents a new multicast routing protocol, called the survivable multicast routing protocol (SMRP), which facilitates fast recovery of multicast sessions in face of persistent failures via local detour paths. Our evaluation results show that SMRP trades end-to-end delay and resource usage for short, and hence fast, recovery paths. For example, under a certain set of parameter values, SMRP shortens the recovery path by 20% with only a 5% increase of end-to-end delay and resource usage. Moreover, several design enhancements have made SMRP efficient, robust, flexible and scalable.
Design and fabrication of a microimpedance biosensor for bacterial detection

A biosensor for bacterial detection was developed based on microelectromechanical systems, heterobifunctional crosslinkers and immobilized antibodies. The sensor detected the change in impedance caused by the presence of bacteria immobilized on interdigitated gold electrodes and was fabricated from (100) silicon with a 2-/spl mu/m layer of thermal oxide as an insulating layer. The sensor active area is 9.6 mm/sup 2/ and consists of two interdigital gold electrode arrays measuring 0.8 /spl times/ 6 mm. Escherichia coli specific antibodies were immobilized to the oxide between the electrodes to create a biological sensing surface. The impedance across the interdigital electrodes was measured after immersing the biosensor in solution. Bacteria cells present in the sample solution attached to the antibodies and became tethered to the electrode array, thereby causing a change in measured impedance. The biosensor was able to discriminate between different cellular concentrations from 10/sup 5/ to 10/sup 7/ CFU/mL in pure culture. The sample testing process, including data acquisition, required 5 min. The design, fabrication, and testing of the biosensor is discussed along with the implications of these findings toward further biosensor development.
Through Gritted Teeth and Clenched Jaw: Court-Initiated Sanctions in Bankruptcy Opinions

This article discusses what types of behavior can trigger a bankruptcy court's initiation of sanctions against an attorney.
AgDscam, a hypervariable immunoglobulin domain-containing receptor of the Anopheles gambiae innate immune system.

Activation of the insect innate immune system is dependent on a limited number of pattern recognition receptors (PRRs) capable of interacting with pathogen-associated molecular pattern. Here we report a novel role of an alternatively spliced hypervariable immunoglobulin domain-encoding gene, Dscam, in generating a broad range of PRRs implicated in immune defense in the malaria vector Anopheles gambiae. The mosquito Down syndrome cell adhesion molecule gene, AgDscam, has a complex genome organization with 101 exons that can produce over 31,000 potential alternative splice forms with different combinations of adhesive domains and interaction specificities. AgDscam responds to infection by producing pathogen challenge-specific splice form repertoires. Transient silencing of AgDscam compromises the mosquito's resistance to infections with bacteria and the malaria parasite Plasmodium. AgDscam is mediating phagocytosis of bacteria with which it can associate and defend against in a splice form–specific manner. AgDscam is a hypervariable PRR of the A. gambiae innate immune system.
Copy Number Suppressors of the Aspergillus nidulans nimA1 Mitotic Kinase Display Distinctive and Highly Dynamic Cell Cycle-Regulated Locations

The Aspergillus nidulans NIMA kinase is essential for mitosis and is the founding member of the conserved NIMA-related kinase (Nek) family of protein kinases. To gain insight into NIMA function, a copy number suppression screen has been completed that defines three proteins termed MCNA, MCNB, and MCNC (multi-copy-number suppressor of nimA1 A, B, and C). All display a distinctive and dynamic cell cycle-specific distribution. MCNC has weak similarity to Saccharomyces cerevisiae Def1 within a shared CUE-like domain. MCNC, like Def1, is a cytoplasmic protein with slow mobility during sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its deletion causes polarization defects and a small colony phenotype. MCNC enters nuclei during mitosis. In contrast, MCNB is a nuclear protein displaying increased nuclear levels as cells progress through interphase but is lost from nuclei at mitosis. MCNB is highly related to the Schizosaccharomyces pombe forkhead transcription factor Sep1 and is likely a transcriptional activator of nimA. Most surprisingly, MCNA, a protein restricted to the aspergilli and pathogenic systemic dimorphic fungi (the Eurotiomycetes), defines a nuclear body located near nucleoli at the nuclear periphery of G2 nuclei. During progression through mitosis, the MCNA body is excluded from nuclei. Cytoplasmic MCNA bodies then diminish during early stages of interphase, and single MCNA bodies are formed within nuclei as interphase progresses. Three sites of MCNA phosphorylation were mapped and mutated to implicate proline-directed phosphorylation in the equal segregation of MCNA during the cell cycle. The data indicate all three MCN proteins likely have cell cycle functions.
Group decision-making in chacma baboons: leadership, order and communication during movement

Background Group coordination is one of the greatest challenges facing animals living in groups. Obligatory trade-offs faced by group members can potentially lead to phenomena at the group level such as the emergence of a leader, consistent structure in the organization of individuals when moving, and the use of visual or acoustic communication. This paper describes the study of collective decision-making at the time of departure (i.e. initiation) for movements of two groups of wild chacma baboons (Papio ursinus). One group was composed of 11 individuals, whilst the other consisted of about 100 individuals.
Factors in rubber compounds affecting the adhesion of polyester tire cords

Several factors in rubber stocks were demonstrated to be important in the adhesion of polyester tire cords to rubber compounds. The retained adhesion of polyester tire cords, determined after heat-aging laboratory cord–rubber samples at elevated temperatures, was improved by (a) eliminating the sources of amines in the elastomers and compounding ingredients, (b) reducing the moisture content of the stocks, (c) increasing the overall water vapor permeability (WVP) of the cord–rubber composite, and (d) lowering the modulus of the stock. Sulfenamide cure accelerators and water were found to be synergistic in reducing the retained adhesion of polyester cord after in-rubber aging at high temperatures. The harmful effects of amines released from sulfenamides during curing and heat aging were eliminated by compounding the stocks with accelerators that do not form amines. Aliphatic diamines present as nonrubber components in natural rubber (NR) were shown to be detrimental to adhesion. Since synthetic polyisoprene rubber (IR) does not contain any nonrubber components, IR stocks containing the nonamine accelerator benzothiazyl disulfide (MBTS) showed excellent retained adhesion to polyester cords. A recently developed nonamine-type accelerator gave adhesion essentially equal to MBTS but showed excellent scorch safety and high stock modulus typical of sulfenamides. The retained adhesion in IR stocks after heat aging was less dependent on moisture level and stock modulus than in NR stocks. Finally, examples of practical rubber compounds giving improved retained adhesion to polyester tire yarns are given.
Three-dimensional constrained variational analysis: Approach and application to analysis of atmospheric diabatic heating and derivative fields during an ARM SGP intensive observational period

Atmospheric vertical velocities and advective tendencies are essential large-scale forcing data to drive single-column models (SCMs), cloud-resolving models (CRMs), and large-eddy simulations (LESs). However, they cannot be directly measured from field measurements or easily calculated with great accuracy. In the Atmospheric Radiation Measurement Program (ARM), a constrained variational algorithm (1-D constrained variational analysis (1DCVA)) has been used to derive large-scale forcing data over a sounding network domain with the aid of flux measurements at the surface and top of the atmosphere (TOA). The 1DCVA algorithm is now extended into three dimensions (3DCVA) along with other improvements to calculate gridded large-scale forcing data, diabatic heating sources (Q1), and moisture sinks (Q2). Results are presented for a midlatitude cyclone case study on 3 March 2000 at the ARM Southern Great Plains site. These results are used to evaluate the diabatic heating fields in the available products such as Rapid Update Cycle, ERA-Interim, National Centers for Environmental Prediction Climate Forecast System Reanalysis, Modern-Era Retrospective Analysis for Research and Applications, Japanese 55-year Reanalysis, and North American Regional Reanalysis. We show that although the analysis/reanalysis generally captures the atmospheric state of the cyclone, their biases in the derivative terms (Q1 and Q2) at regional scale of a few hundred kilometers are large and all analyses/reanalyses tend to underestimate the subgrid-scale upward transport of moist static energy in the lower troposphere. The 3DCVA-gridded large-scale forcing data are physically consistent with the spatial distribution of surface and TOA measurements of radiation, precipitation, latent and sensible heat fluxes, and clouds that are better suited to force SCMs, CRMs, and LESs. Possible applications of the 3DCVA are discussed.
Effects of centroid location on determination of earthquake mechanisms using long-period surface waves

Determination of shallow earthquake source mechanisms by inversion of longperiod (150 to 300 sec) Rayleigh waves requires epicentral locations with greater accuracy than that provided by routine source locations of the National Earthquake Information Center (NEIC) and International Seismological Centre (ISC). The effects of epicentral mislocation on such inversions are examined using synthetic calculations as well as actual data for three large Mexican earthquakes. For Rayleigh waves of 150-sec period, an epicentral mislocation of 30 km introduces observed source spectra phase errors of 0.6 radian for stations at opposing azimuths along the source mislocation vector. This is larger than the 0.5-radian azimuthal variation of the phase spectra at the same period for a thrust fault with 15 ° dip and 24-km depth. The typical landward mislocation of routinely determined epicenters of shallow subduction zone earthquakes causes source moment tensor inversions of long-period Rayleigh waves to predict larger fault dip than indicated by teleseismic P-wave first-motion data. For dip-slip earthquakes, inversions of long-period Rayleigh waves that use an erroneous source location in the down-dip or along-strike directions of a nodal plane, overestimate the strike, dip, and slip of that nodal plane. Inversions of strike-slip earthquakes that utilize an erroneous location along the strike of a nodal plane overestimate the slip of that nodal plane, causing the second nodal plane to dip incorrectly in the direction opposite to the mislocation vector. The effects of epicentral mislocation for earthquakes with 45 ° dip-slip fault mechanisms are more severe than for events with other fault mechanisms. Existing earth model propagation corrections do not appear to be sufficiently accurate to routinely determine the optimal surface-wave source location without constraints from body-wave information, unless extensive direct path (R1) data are available or empirical path calibrations are performed. However, independent surface-wave and body-wave solutions can be remarkably consistent when the effects of epicentral mislocation are accounted for. This will allow simultaneous unconstrained body-wave and surface-wave inversions to be performed despite the well known difficulties of extracting the complete moment tensor of shallow sources from fundamental modes.