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Irrigated field experiments were conducted near Torrington, WY, during the 2001 to 2002 (year 1) and 2002 to 2003 (year 2) winter wheat growing seasons to evaluate cultivar response to different imazamox rates, adjuvants, and application timings. Five cultivars were treated postemergence in the early fall (EF), late fall (LF), or early spring (ES) with imazamox at 54 or 108 g ai/ha, including either nonionic surfactant (NIS) at 0.25% or methylated seed oil (MSO) at 1% (v/v) as adjuvants. A 28% urea ammonium nitrate solution at 1% (v/v) was included with all treatments. Spring injury was more severe in year 1 than year 2. Severe spring injury on ‘AP502 CL’, ‘Above’, ‘IMI-Fidel’, ‘IMI-Jagger’, and ‘IMI-Madsen’ was linked to fall application of 108 g/ha imazamox with MSO. Imazamox applied at 108 g/ha plus MSO applied in the fall consistently injured all cultivars more than the same rate with NIS and 54 g/ha imazamox regardless of adjuvant and timing, although severity of injury in the experiments differed between EF and LF timings in years 1 and 2, respectively. Correlation analysis supports injury reduced reproductive tillers per meter of row and wheat yields and increased the number of seeds per spike in year 1. The reduction of reproductive tillers per meter of row in year 1 was likely the result of severe injury caused by 108 g/ha imazamox applied in the EF coupled with little snow cover to protect against cold winter temperatures. Wheat yield in year 1 was reduced by 108 g/ha imazamox applied in the early fall; however, imazamox applied at 54 g/ha with either adjuvant in EF, LF, or ES were safe. Yield parameters and wheat yields in year 2 were not affected by imazamox rate, adjuvant, timing, or interactions of these factors.

This paper describes the Research Communications Studio (RCS), a structured approach for teaching undergraduate researchers to do authentic written, oral, and graphical communications tasks while they are learning to do research. In the RCS, small groups of undergraduate researchers meet weekly with a communications faculty member, an engineering graduate student mentor, and a communications graduate research assistant. The project is built upon social constructivist theory that recognizes the interdependence between communication, cognitive development, and metacognition. It investigates knowledge construction within a small-group context of distributed cognition, the concept that each group member's expertise is available to other group members. Data from surveys indicate that engineering faculty members, graduate student mentors, and undergraduate participants were very positive about the progress participants made in cognitive development and communications abilities. Analysis of participants' reflective writings shows the development of metacognitive abilities necessary for self-directed, life-long learning.

Field experiments were conducted at five locations in Kansas, Nebraska, and Wyoming to determine the effects of imazamox rate and application timing on winter annual grass control and crop response in imidazolinone-tolerant winter wheat. Imazamox at 35, 44, or 53 g ai/ha applied early-fall postemergence (EFP), late-fall postemergence, early-spring postemergence (ESP), or late-spring postemergence (LSP) controlled jointed goatgrass at least 95% in all experiments. Feral rye control with imazamox was 95 to 99%, regardless of rate or application timing at Hays, KS, in 2001. Feral rye control at Sidney, NE, and Torrington, WY, was highest (78 to 85%) with imazamox at 44 or 53 g/ha. At Sidney and Torrington, feral rye control was greatest when imazamox was applied EFP. Imazamox stunted wheat

Background: The neurodegenerative process in Alzheimer’s disease (AD) and in the Lewy body variant of AD (LBV) patients is characterized by cholinergic dysfunction and deposition of amyloid β-peptide (Aβ) 1–40 and 1–42; however, the differential effects of Aβ species on the cholinergic system are not completely clear. Objective: To better understand the relationship between levels of Aβ1–40 and 1–42 on cholinergic deficits in AD and LBV patients. Methods: Levels of choline acetyltransferase (ChAT) activity and ChAT immunoreactivity in the plaques in the frontal cortex of patients with AD and LBV were correlated with Aβ1–42 and 1–40 levels determined by ELISA and with neuropathologic and neurologic markers. Results: Although the overall levels of ChAT activity were reduced in AD and LBV cases, there was a direct correlation with Aβ1–42 levels. Furthermore, patients with high Aβ1–42 levels had more abundant cholinergic dystrophic neurites in the plaques than cases with lower Aβ1–42. Conclusion: Aβ1–42 may also trigger cholinergic dysfunction by promoting aberrant neuritic sprouting.

Both monoamine oxidase (MAO) A and MAO B in the brain have been implicated in the etiology of Alzheimer's disease. MAO B is elevated in plaque-associated glia in Alzheimer brain. Elevations in MAO A in Alzheimer neurons have been linked to increases in neurotoxic metabolites and neuron loss. We investigated the relationship between cognitive function in Alzheimer patients and post-mortem prefrontal cortex MAO A and B activities. Prefrontal cortex tissue from 92 Alzheimer patients and 74 neurologically normal subjects was obtained at autopsy and analyzed for activities of MAO A and B by radioenzymatic methods. Mini Mental Status Exam was performed on Alzheimer patients within 1 year of death. Alzheimer brains were analyzed for Braak stage, tangles, plaques and choline acetyltransferase activity. Prefrontal cortex MAO B activity was significantly increased by 16% in Alzheimer patients versus normals, whereas MAO A activity was significantly decreased by 17% in these same patients. Neither MAO A nor MAO B activities correlated with cognitive function (MMSE score), choline acetyltransferase activity, plaques, neurofibrillary tangles, Braak stage, or age of disease onset in the Alzheimer patients. With increasing Alzheimer duration or increasing Braak stage, MMSE scores and choline acetyltransferase activity declined, but levels of MAO A and B in prefrontal cortex were unchanged. Patients in the upper quintile for MAO A or B activity did not differ significantly from those in the lowest quintile with respect to MMSE scores or age of Alzheimer disease onset. We conclude that the changes in MAO A and B in the prefrontal cortex occur very early in Alzheimer's disease and remain relatively constant as the disease progresses.

This book presents the reader with both facts and conclusions drawn from three case studies. Authors Ralph Espach, Daniel Haering, Javier Meléndez Quiñonez, and Miguel Castillo Giron focus on the lack of security along Guatemala’s borders and the serious narcotics trafficking, execution-style mass murders, and other severe public security issues that have developed as a result. This research looks closely at the effects of criminal organizations and illicit trafficking within the three particular border municipalities of Guatemala—Sayaxché, Gualán, and Malacatán. The three areas are compared demographically and economically, and through which a deeper analysis is developed on creating better border control through the behaviors of the local communities themselves.

The Elder Justice Act ( a part of the Patient Protection and Affordable Care Act of 2010 ) focuses on the development of a comprehensive mechanism to “prevent, detect, treat, intervene in, and prosecute elder abuse, neglect, and exploitation.” Elements of the Act that offer opportunities for nurses to demonstrate their advocacy role on behalf of older adults include (a) participating in the training of ombudsmen and/or becoming an ombudsman; (b) serving on the Elder Justice Act’s Advisory Board on Elder Abuse, Neglect, and Exploitation; (c) working in either a stationary or mobile forensic center dedicated to addressing elder abuse; (d) having an active role in the curriculum design and implementation of degree and certificate programs to build competency in gerontology and gerontological nursing; and (e) providing consultation to long-term care facilities in the areas of staff recruitment and quality of care.

Effective negative capacitance has been postulated in ferroelectrics because there is a hysteresis in plots of polarization-electric field. Compelling experimental evidence of effective negative capacitance is presented here at room temperature in engineered devices, where it is stabilized by the presence of a paraelectric material. In future integrated circuits, the incorporation of such negative capacitance into MOSFET gate stacks would reduce the subthreshold slope, enabling low power operation and reduced self-heating.

Apolipoprotein E (apoE) is known to bind to at least five receptors, including the low-density lipoprotein (LDL) receptor-related protein (LRP), very low density LDL receptor (VLDL-R), LDL-R, apoE receptor 2 (apoER2), and megalin/gp330. In this context, the main objective of the present study was to better understand the contributions of LRP and LDL-R to the in vivo neurotrophic effects of apoE. For this purpose, apoE-deficient and receptor-associated protein (RAP)-deficient mice were infused with recombinant apoE3, RAP, or saline. Infusion of apoE3 into apoE-deficient mice resulted in amelioration of degenerative alterations of pyramidal neurons, but had no effect on somatostatin-producing interneurons. In contrast, infusion of apoE3 into RAP-deficient mice resulted in amelioration of degenerative alterations of somatostatin-producing interneurons. LRP and LDL-R levels were significantly reduced in RAP-deficient mice, but significantly increased in the apoE-deficient mice. In contrast, levels of apoE were reduced in the RAP-deficient mice compared to wildtype controls, suggesting that neurotrophic effects of apoE3 in the RAP-deficient mice were related to a combined deficit in endogenous apoE and selected apoE receptors. Furthermore, in apoE-deficient mice, infusion of apoE3 had a neurotrophic effect on somatostatin-producing interneurons only when combined with RAP, suggesting that increased expression of apoE receptors in apoE-deficient mice prevented apoE from rescuing somatostatin-producing neurons. This study supports the contention that some of the in vivo neurotrophic effects of apoE are mediated by LRP and LDL-R and that a critical balance between levels of apoE and its receptors is necessary for the differential neurotrophic effects to appear.

The synthesis of single-walled carbon nanotubes (SWNTs) in sooting flames is reported. This method offers a viable path towards low-cost large-scale synthesis, which is lacking in arc- and laser-based SWNT synthetic techniques. As with other methods, the growth of the SWNTs in the flame is catalyzed by the presence of metals. Iron and nickel were introduced into the flames by subliming their bis(cyclopentadienyl) derivatives into an inert gas feed line that mixes with the hydrocarbon fuel and oxygen at the burner surface. Acetylene and ethylene are both suitable fuel choices for SWNT synthesis. While no SWNTs could be detected when benzene was used as the fuel, long metal-filled multiwalled nanotubes (MWNTs) with many defects were abundant. The effect of the fuel's chemical identity is discussed within the formation mechanisms for vapor-grown carbon fibers (VGCFs), SWNTs, MWNTs, and fullerenes.

Superficial gains made by Black students studying in the United States have created the illusion that college access and retention rates have improved. However, to support their education, commuter students from lower socioeconomic communities have developed coping skills that inhibit positive social adjustment. This article presents an examination of Black commuter-student relationships and associations.

If members of a suite of sensors from which fusion is to be carried out are not colocated, it is unreasonable to assume that they share a common resolution cell grid; this is generally ignored in the data fusion community. We explore the effects of such "noncoincidence", and we find that what at first seems to be a problem can in fact be exploited. The idea is that a target is known to be confined to an intersection of overlapping resolution cells, and this overlap is generally small. We examine noncoincidence from two viewpoints: tracking and detection. With respect to tracking our analysis is first static, by which is meant that we establish the decrease in measurement error; and then dynamic, meaning that the overall effect in the tracking problem is quantified. The detection viewpoint considers noncoincidence as it has impact on a predetection fusion system. Specifically, the role of the fusion rule is examined, and the use of noncoincidence to improve detection performance (rather than that of tracking) is explored.

Cell shape and membrane remodeling rely on regulated interactions between the lipid bilayer and cytoskeletal arrays at the cell cortex. During cytokinesis, animal cells build an actomyosin ring anchored to the plasma membrane at the equatorial cortex. Ring constriction coupled to plasma membrane ingression separates the two daughter cells [1]. Plasma-membrane lipids influence membrane biophysical properties such as membrane curvature and elasticity and play an active role in cell function [2], and specialized membrane domains are emerging as important factors in regulating assembly and rearrangement of the cytoskeleton [3]. Here we show that mutations in the gene bond [4], which encodes a Drosophila member of the family of Elovl proteins that mediate elongation of very-long-chain fatty acids [5], block or dramatically slow cleavage-furrow ingression during early telophase in dividing spermatocytes. In bond-mutant cells at late stages of division, the contractile ring frequently detaches from the cortex and constricts or collapses to one side of the cell, and the cleavage furrow regresses. Our findings implicate very-long-chain fatty acids or their derivative complex lipids in allowing supple membrane deformation and the stable connection of cortical contractile components to the plasma membrane during cell division.

Fullerenes have been synthesized in sooting flames using a two-ring feedstock (1,2,3,4-tetrahydronaphthalene). Regardless of how yield is measured, dramatic improvement over a single-ring feedstock (toluene) was observed. Implications for the formation of fullerenes in sooting flames are briefly discussed.

Recent studies have shown that deficient functioning of glutamate transporters (GTs) in Alzheimer disease (AD) might lead to neurodegeneration via excitotoxicity; however, the characteristics of cell death and pathways involved are not yet clear. The main objective of the present study was to determine if deficient GT functioning in AD could be associated with cell damage and caspase activation. For this purpose, we analyzed the levels of caspase-1 and 3 immunoreactivity in AD and control brains and correlated this data with the numbers of cells displaying DNA fragmentation, GT activity, and amyloid precursor protein (APP) mRNA expression. Compared to controls, AD cases showed extensive positive labeling of neurons and glial cells with an assay for DNA fragmentation suggestive of cell damage, as well as increased neuronal caspase-3 and Bcl-2 immunoreactivity. Linear regression analysis showed a strong negative correlation between GT activity and apoptosis, and between deficient GT functioning and caspase-3 immunoreactivity. Neurons displaying DNA fragmentation presented more intense caspase-3 immunoreactivity than intact neurons. In addition, the altered ratio between the spliced forms of APP correlated with DNA fragmentation and caspase-3 immunolabeling. Taken together, these results support the possibility that excitotoxic injury associated with deficient GT functioning and an imbalance in ratio of spliced APP forms might lead to cell death via caspase-3 activation.

The loss of neocortical synapses that occurs in Alzheimer's disease (AD) has been shown to correlate with cognitive decline. In addition, marked losses in the cholinergic system in AD, specifically choline acetyltransferase (ChAT) activity and high affinity presynaptic neuronal nicotinic cholinergic receptors (nAChRs), have also been described. We hypothesized that in AD, the loss of [3H]-ligand binding to nAChRs, which are largely presynaptic, would correlate with changes in two other presynaptic markers: synaptophysin (Syn), a measure of synaptic density, and ChAT activity. The midfrontal (MF) cortex of 36 autopsy confirmed (NIA and CERAD criteria) AD patients (mean death age +/- SD 80.1 +/- 8.4 years) who met NINDS-ADRDA criteria for a clinical diagnosis of probable or possible AD, and 11 nondemented controls (mean death age +/- SD 77.9 +/- 8.0) were examined. Synapse counts were quantified by a dotimmunobinding assay for Syn. ChAT activity was assessed by standard biochemical assays. Nicotinic cholinergic receptor binding was assayed using the high affinity nicotinic agonist [3H]-(+/-)-epibatidine ([3H]-EPI). The mean +/- SD Syn in AD (83.4 +/- 31.9 arbitrary units (AU)/mg protein) was significantly lower than controls (126.1 +/- 19.9, p = 0.0003; t-test). The mean ChAT activity in AD (139.0 +/- 75.6 nmol ACh/hr/100 mg protein) was significantly lower than controls (219.6 +/- 70.8, p = 0.004). The mean [3H]-EPI total binding in AD (6.2 +/- 2.8 fmol/mg protein) was significantly lower than controls (14.8 +/- 3.2; p < 0.0001). Syn correlated with [3H]-EPI binding in AD (r = 0.48, p = 0.006; Pearson) but ChAT did not (r = -0.20, p = 0.34). We conclude that loss of high affinity nAChR binding correlates with loss of synapses in AD. The lack of correlation between [3H]-EPI binding and ChAT activity suggests that the targeted receptor populations may not be located exclusively on cholinergic neurons.

Commentary: When “Thucydides and the Plague in Athens: The Roots of Scientific Writing” was written in 1988, genre analysis was an emerging area for scholarship. Thucydides' Historiae, which includes numerous political speeches in context, provides a rich resource for exploring the ancient roots of rhetorical genres. Thucydides' text also sheds light on the origin of a specific scientific genre - the medical case history. In describing a devastating plague in Athens, Thucydides uses the Hippocratic approach, following an ancient genre or form that is remarkably similar to the modern medical case history. Thucydides' case history of the Athenian plague enabled 20th-century epidemiologists to establish a diagnosis of the illness (influenza plus toxic shock syndrome), predict its return, and validate their diagnosis during a 1987 flu epidemic. Although “Thucydides and the Plague in Athens” only hints at Thucydides' genre knowledge, his case history of the plague and his presentation of speeches display considerable insight into the social construction and function of these recurring forms. In explaining the speeches in his text, for example, Thucydides says, “[M]y habit has been to make the speakers say what was in my opinion demanded of them by the various occasions” (1.22). He prefaces his account of the plague with a statement of purpose: to help future scholars recognize future outbreaks of the same illness. These remarks, viewed in the context of genre theory today, suggest that Thucydides not only knew how to use genres but also understood their social origin and purposes.

The diversity of molecular structures exhibited by fullerenes1 suggests a wide range of interesting and useful properties. Several fullerenes are now considered to be well characterized, but only minor variations in their chemical and physical properties have been observed2. Here we show that there are in fact two distinct classes of fullerenes, with some very different chemical properties. Members of the first class, typified by C60 and C70, have large energy gaps between the highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO), and are soluble in many organic solvents. The second, previously unrecognized class is represented by C74 and selected isomers of the higher fullerenes, such as that of C80 with icosahedral symmetry: these are either free radicals or have small HOMO–LUMO gaps. Like radical metallofullerenes, they are kinetically unstable and react readily to form insoluble, polymerized solids. These intermolecular bonds can be broken by electrochemical reduction. After reducing them to soluble anions, we have been able to isolate and characterize these new fullerenes.

Excitatory neurotransmitters such as glutamate are required for the normal functioning of the central nervous system but can trigger excitotoxic neuronal injury if allowed to accumulate to abnormally high levels. Their extracellular levels are controlled primarily by transmitter uptake into astrocytes. Here, we demonstrate that the amyloid protein precursor may participate in the regulation of this important process. The amyloid protein precursor has been well conserved through evolution, and a number of studies indicate that it may function as an endogenous excitoprotectant. However, the mechanisms underlying this neuroprotective capacity remain largely unknown. At moderate levels of expression, human amyloid protein precursors increased glutamate/aspartate uptake in brains of transgenic mice, with the 751-amino acid isoform showing greater potency than the 695-amino acid isoform. Cerebral glutamate/aspartate transporter protein levels were higher in transgenic mice than in non-transgenic controls, whereas transporter mRNA levels were unchanged. Amyloid protein precursor-dependent stimulation of aspartate uptake by cultured primary astrocytes was associated with increases in protein kinase A and C activity and could be blocked by inhibitors of these kinases. The stimulation of astroglial excitatory amino acid transport by amyloid protein precursors could protect the brain against excitotoxicity and may play an important role in neurotransmission.

Near infrared photoluminescence spectra of Er3+ have been measured in samples containing erbium metallofullerenes. The structured emission lines in the region of 1.52 microns are typical of Er3+ emission. Mass spectrometry measurements on the samples reveal the presence of erbium metallofullerenes in the samples. Possible sources of the observed signal are discussed in terms of specific erbium metallofullerenes identified in the mass spectrum. In addition, differences between the emission spectra of samples generated from raw soot and toluene extract are presented and discussed.

Early in the system design process, a design method must be chosen. This choice is usually dictated by what methods the designer has previously used, not by an open selection process. We provide descriptions of some available design methods and examples of their use. We develop benchmark problems that are solved by a variety of design methods and which identify characteristics of problems that might make one system design method more or less appropriate. The question we wish to answer is, "For which type of problem is each method best?" If a system is to be built, then that system must ultimately be described as a collection of state machines. However, these state machines are often not created by the systems engineers. The systems engineers use some method to create a high-level abstraction of the desired system. Then they turn this abstraction over to the specialty engineers who actually reduce it to a collection of state machines. We present solutions for a simple design problem by using the following 11 high-level system design methods: state transition diagrams, algorithmic state machine (ASM) notation, model-based system engineering, graphical description language, RDD-100, structured analysis, functional decomposition, object-oriented analysis (OOA) with Shlaer-Mellor notation, OOA and object-oriented design (OOD) with Booch notation, an operational evaluation modeling-directed graph, and IDEF0. Each method was used by an expert user of that method. The solutions presented make it obvious that the choice of a design method greatly effects the resulting system design.

Vesicle trafficking and new membrane addition at the cleavage furrow have been extensively documented. However, less clear is the old idea that expansion at the cell poles occurs during cytokinesis. We find that new membrane is added to the cell poles during anaphase, causing the plasma membrane to expand coincident with the constriction of the contractile ring and may provide a pushing force for membrane ingression at the furrow. This membrane addition occurs earlier during mitosis than membrane addition at the furrow and is dependent on actin and astral microtubules. The membrane that is added at the polar regions is compositionally distinct from the original cell membrane in that it is devoid of GM1, a component of lipid rafts. These findings suggest that the growth of the plasma membrane at the cell poles during cell division is not due to stretching as previously thought, but due to the addition of compositionally unique new membrane. © 2012 Wiley Periodicals, Inc

Because cancer care requires a multifaceted approach, providing useful and timely information to people with colorectal cancer may be fragmented and inconsistent. Our interest was in examining what has and has not captured the attention of researchers speaking to the information needs of people with colorectal cancer. We followed Arksey and O'Malley's framework for the methodology of scoping review. Focusing solely on colorectal cancer, we analysed 239 articles to get a picture of which information needs and sources of information, as well as the timing of providing information, were attended to. Treatment-related information received the most mentions (26%). Healthcare professionals (49%) were mentioned as the most likely source of information. Among articles focused on one stage of the care continuum, post-treatment (survivorship) received the most attention (16%). Only 27% of the articles consulted people with colorectal cancer and few attended to diet/nutrition and bowel management. This study examined the numerical representation of issues to which researchers attend, not the quality of the mentions. We ponder, however, on the relationship between the in/frequency of mentions and the actual information needs of people with colorectal cancer as well as the availability, sources and timing of information.

The amyloid precursor protein (APP) is involved in Alzheimer's disease (AD) because its degradation products accumulate abnormally in AD brains and APP mutations are associated with early onset AD. However, its role in health and disease appears to be complex, with different APP derivatives showing either neurotoxic or neurotrophic effects in vitro. To elucidate the effects APP has on the brain in vivo, cDNAs encoding different forms of human APP (hAPP) were placed downstream of the neuron-specific enolase (NSE) promoter. In multiple lines of NSE-hAPP transgenic mice neuronal overexpression of hAPP was accompanied by an increase in the number of synaptophysin immunoreactive (SYN-IR) presynaptic terminals and in the expression of the growth-associated marker GAP-43. In lines expressing moderate levels of hAPP751 or hAPP695, this effect was more prominent in homozygous than in heterozygous transgenic mice. In contrast, a line with several-fold higher levels of hAPP695 expression showed less increase in SYN-IR presynaptic terminals per amount of hAPP expressed than the lower expressor lines and a decrease in synaptotrophic effects in homozygous compared with heterozygous offspring. Transgenic mice (2–24 months of age) showed no evidence for amyloid deposits or neurodegeneration. These findings suggest that APP may be important for the formation/maintenance of synapses in vivo and that its synaptotrophic effects may be critically dependent on the expression levels of different APP isoforms. Alterations in APP expression, processing or function could contribute to the synaptic pathology seen in AD.

There has been a great deal of theoretical study into decentralized detection networks composed of similar (often identical), independent sensors, and this has produced a number of satisfying theoretical results. At this point it is perhaps worth asking whether or not there is a great deal of point to such study-certainly two sensors can provide twice the illumination of one, but what does this really translate to in terms of performance? We take as our metric the ground area covered with a specified Neyman-Pearson detection performance. To be fair, the comparison will be of a multisensor network to a single-sensor system where both have the same aggregate transmitter power. The situations examined are by no means exhaustive but are, we believe, representative. Is there a case? The answer, as might be expected, is "sometimes." When the statistical situation is well behaved there is very little benefit to a fused system; however, when the environment is hostile the gains can be significant. We see, depending on the situation, gains from colocation, gains from separation, optimal gains from operation at a "fusion range," and sometimes no gains at all. >

Neurodegenerative disorders are characterized by damage to selective neuronal populations (1) that could be followed or proceeded by synaptic injury (2). The mechanisms triggering cell death and synaptic damage in these disorders might be related to gain of a toxic property and/or loss of neuroprotective capacity of a specific neuronal protein (3). Many of these neuronal molecules play an important role in the maintenance and functioning of the synaptic apparatus (4,5). Therefore, specific mutations and other alterations of synaptic proteins might result in particular neurodegenerative diseases. In this regard, recent studies have shown that molecules involved in the pathogenesis of Alzheimer's disease (AD) in fact have a synaptic location. Examples of such proteins include amyloid precursor protein (APP) (6-8), nonamyloid-β component precursor (NACP) (9), and presenilin 1 and 2 (10-12). Furthermore, other neurodegenerative disorders such as Huntington's disease (HD) (13,14), Parkinson's disease (PD) (15-17), Creutzfeldt-Jakob disease (CJD) (18), and myotonic dystrophy (19) have turned out to be the result of mutations in proteins that concentrate at the synaptic site. Therefore, in order to better understand the mechanisms of central nervous system (CNS) dysfunction in neurodegenerative disorders, it is important to determine the concentrations of specific synaptic proteins at the synaptic site, as well as to determine overall synaptic density in specific brain regions. For example, in AD, memory deficits in early stages of the disease are associated with synaptic loss in the molecular layer of the hippocampal dentate gyrus, which reflects degeneration of the perforant pathway (2,20).

Recent evidence has revealed that the dynein motors and highly conserved signaling proteins are localized within the ciliary 9 + 2 axoneme. One key mechanism for regulation of motility is phosphorylation. Here, we review diverse evidence, from multiple experimental organisms, that ciliary motility is regulated by phosphorylation / dephosphorylation of the dynein arms through kinases and phosphatases that are anchored immediately adjacent to their axonemal substrates.

Fullerenes have been produced efficiently by direct vaporization of carbon in focused sunlight. Large-scale solar furnace implementations of this simple process may be uniquely capable of producing fullerenes and doped fullerenes in large amounts while avoiding the yield-limiting problems encountered with carbon arcs or plasmas. Evidence is presented that the worst of these problems is photochemical destruction of the fullerenes in the light from the arc. Solar furnaces can mitigate this problem both by avoiding the intense ultraviolet radiation associated with arcs and by preventing clustering of the carbon vapor until it passes into a relatively dark cluster formation and annealing zone. 21 refs., 4 figs.

About one quarter of Alzheimer's disease patients have been found to have concomitant subcortical and neocortical Lewy bodies (LBs). We compared the aberrant neuronal sprouting and the extent of neuritic and synaptic damage in these Lewy body variant of Alzheimer's disease (LBV), with the same pathologic alterations in Alzheimer's disease without LBs (AD). More of the thioflavine-S-positive senile plaques of the LBVs contained growth associated protein 43 (GAP-43), a marker of neuritic growth and sprouting. Compared to AD, the LBVs had 39% more GAP-43-positive plaques in the frontal cortex, and 53% more in the hippocampus. These neuritic alterations were accompanied by an accumulation of amyloid precursor protein and phosphorylate neurofilaments.. Synapse loss was the same in LBV and AD. These results suggest more extensive aberrant neuronal sprouting in LBV than in AD.

The electronic structure of Ca@C60 in the gas phase was probed by ultraviolet photoelectron spectroscopy (UPS) of Ca@C−60. The electron affinity of Ca@C60 was found to be 3.0 eV. The spectrum suggests that Ca donates its two 4s electrons to the C60 t1u LUMO. Ab initio self-consistent field Hartree-Fock calculations were performed on Ca@C60 at four different symmetries, Ih, D3d, D5d, and C5v. We found that the C5v symmetry has the lowest energy with the central Ca2+ ion 0.7 A away from the center of C60 and that Ca@C60 has a 3A2 triplet electronic ground state in C5v symmetry.

Patients with parkinsonism-dementia complex (PDC) of Guam showed moderate loss of choline acetyl transferase activity in the midfrontal and inferior parietal cortex, and severe loss in the superior temporal cortex. This deficit was similar to that seen in Alzheimer's disease and less severe than Lewy body disease. Thus, cholinergic deficits in the neocortex might contribute to some of the cognitive alterations in PDC of Guam.

The expression levels of three synaptic proteins (synaptophysin, synaptotagmin, and growth-associated protein 43 [GAP43]) in AD cases clinically classified by Clinical Dementia Rating (CDR) score were analyzed. Compared with control subjects (CDR = 0), mild (early) AD (CDR = 0.5 to 1) cases had a 25% loss of synaptophysin immunoreactivity. Levels of synaptotagmin and GAP43 were unchanged in mild AD, but cases with CDR of >1 had a progressive decrement in these synaptic proteins. Thus, synaptic injury in frontal cortex is an early event in AD.

Silicon clusters in the size range from 5 to 66 atoms were generated by laser vaporization in a supersonic nozzle and injected into the ion trap of a specially‐designed Fourier transform ion cyclotron resonance apparatus. On the positively charged clusters ammonia chemisorption reaction rates were found to vary by over three orders of magnitude as a function of cluster size, with clusters of 21, 25, 33, 39, and 45 atoms being particularly unreactive, and cluster 43 being the most reactive. For the negative cluster ions, 43 was the only cluster found to react substantially. Although the reaction behavior of many clusters clearly indicated that several structural isomers were present with different reaction rates, the strikingly low net reactivity of such clusters as 39 and 45 provides evidence that they have effectively crystallized into a single specially stable form.

Problems in the development of large computer-based systems indicate that a new discipline is needed at the systems engineering level. Designing systems with distributed processing and databases requires analysis of critical end-to-end processing flows to determine feasibility and proper allocation. An expanded skills base would be required to enable either software or systems engineers to perform the necessary tradeoff studies concerning software, hardware, and communication components. This paper informs managers, engineers, educators, and researchers about the need for computer-based systems engineering and the strategic opportunities this discipline provides for systems engineering improvement.

X-ray photoemission spectral probes of endohedral lanthanum—fullerene complexes, La@C n , show that the central La atom is in a formal charge state close to +3, and has been effectively protected from reaction with water an oxygen by the enclosing fullerene cage. Similar results were obtained with endohedral yttrium complexes, Y @C n , and the first carbon-caged metal cluster, Y 2 @C 82 . EPR spectral results are also reported for Y @C 82 which is found to be an S = 1 2 spin system with a 0.48 G hyperfine splitting (at 9.216 GHz) centered at g =1.9999(1).

Both protein kinases and phosphoprotein phosphatases are important components of signal transduction systems in cells. Recent studies in Alzheimer's disease (AD) have shown abnormal protein phosphorylation in the cortex suggesting an alteration in these enzymes. In the present study, an antibody against CD45 was used to analyze the status of this protein phosphotyrosine phosphatase in AD. We studied and quantified the immunohistochemical and immunochemical distribution of this integral membrane protein in control and AD brain. We found that anti-CD45 immunostained the great majority of microglia, both resting and activated. These cells were Ricinus communis agglutinin I positive and glial fibrillary acidic protein and neurofilament negative. The AD frontal cortex showed a 35% (P less than 0.01) increase in the number of anti-CD45 immunoreactive microglia as compared with controls. These results were consistent with the immunoblot quantification of CD45 immunoreactivity following native gel electrophoresis. In AD, 30% of the CD45-immunostained microglia were clustered in the neuritic plaques (about six per plaque) while the remaining 70% were scattered in the neuropil. The AD hippocampus showed an increase in CD45-immunoreactive microglia in the molecular layer of the dentate gyrus. At the ultrastructural level, CD45 immunoreactivity was localized exclusively to the plasma membrane of the microglia. The presence of the anti-CD45 immunoreactivity in microglia suggests the possibility that they may require the presence of CD45 as a cell surface receptor which may regulate cell function through modulation of intracellular signaling.

The authors fabricated and measured cylindrical superconducting current leads composed of a Y/sub 1/Ba/sub 2/Cu/sub 3/O/sub 7/ (YBCO) and Bi/sub 2-x/Pb/sub x/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub 10/ (Pb-BSCCO) that were approximately 20 cm long and 1 cm/sup 2/ in cross section. A steady-state, DC, critical current of 170 (230) A at a temperature of 77 K was measured for YBCO (Pb-BSCCO) using a voltage criterion of 2*10/sup -7/ V ( rho =8*10/sup -10/ Omega -cm). This current was limited by the current-induced self-magnetic field. At a temperature of 63 K this current increased to approximately 390 (465) A. The character of the magnetic field dependence of the critical current and shape of the current-induced voltage curves are different for the two materials.

Silicon clusters in the size range from 5 to 66 atoms were generated by laser vaporization in a supersonic nozzle and injected into the ion trap of a specially‐designed Fourier transform ion cyclotron resonance apparatus. On the positively charged clusters ammonia chemisorption reaction rates were found to vary by over three orders of magnitude as a function of cluster size, with clusters of 21, 25, 33, 39, and 45 atoms being particularly unreactive, and cluster 43 being the most reactive. For the negative cluster ions, 43 was the only cluster found to react substantially. Although the reaction behavior of many clusters clearly indicated that several structural isomers were present with different reaction rates, the strikingly low net reactivity of such clusters as 39 and 45 provides evidence that they have effectively crystallized into a single specially stable form.

Currently available specific synaptic markers have made it possible to estimate the synaptic density by immunochemical techniques. In the present study we labeled the neocortical presynaptic terminals in histological sections of human autopsy tissue with a monoclonal antibody against synaptophysin. The characteristic granular neuropil reaction was quantified by measuring the average optical density (OD) in the different layers of the parietal cortex with the aid of image analysis equipment. The raw neuropil OD was corrected by subtracting the OD of the white matter in the same section. Our study showed that consistent microdensitometric results can be obtained on 5-microns paraffin sections from specimens with less than 8 hr of post-mortem time before fixation, incubated with 5 micrograms/ml of anti-synaptophysin. The corrected OD measurements were slightly larger in neocortical layers II, III, and V than in layers I, IV, and VI, but the differences were not statistically significant. In area 17, layer IV was denser than the others. We conclude that with certain precautions this method can be used to measure relative amounts of synaptophysin-like immunoreactivity and to infer the density of presynaptic boutons in human situations and in animal models.

We have fabricated and measured a high-capacity superconducting current lead composed of a Y1Ba2Cu3O7−x cylinder, 20 cm long and 0.9 cm2 cross section. A steady-state, d.c., critical current of 225 A at a temperature of 77 K was measured in this sample, using a voltage criterion of 2×10−7 V/cm (p = 8×10−10 ohm-cm). This current was limited by the currentinduced, self magnetic field. To our knowledge this is the largest d.c. critical current so far reported in a Y1Ba2Cu3O7−x sample and demonstrates the possibility of using hightemperature superconducting HTS materials for current leads to low-temperature superconducting LTS magnets or in power distribution systems.

The empty interior cavity of fullerenes has long been touted for containment of radionuclides during in vivo transport, during radioimmunotherapy (RIT) and radioimaging for example. As the chemistry required to open a hole in fullerene is complex and exceedingly unlikely to occur in vivo, and conformational stability of the fullerene cage is absolute, atoms trapped within fullerenes can only be released during extremely energetic events. Encapsulating radionuclides in fullerenes could therefore potentially eliminate undesired toxicity resulting from leakage and catabolism of radionuclides administered with other techniques. At the start of this project however, methods for production of transition metal and p-electron metal endohedral fullerenes were completely unknown, and only one method for production of endohedral radiofullerenes was known. They therefore investigated three different methods for the production of therapeutically useful endohedral metallofullerenes: (1) implantation of ions using the high intensity ion beam at the Oak Ridge National Laboratory (ORNL) Surface Modification and Characterization Research Center (SMAC) and fullerenes as the target; (2) implantation of ions using the recoil energy following alpha decay; and (3) implantation of ions using the recoil energy following neutron capture, using ORNL's High Flux Isotope Reactor (HFIR) as a thermal neutron source. While they were unablemore » to obtain evidence of successful implantation using the ion beam at SMAC, recoil following alpha decay and neutron capture were both found to be economically viable methods for the production of therapeutically useful radiofullerenes. In this report, the procedures for preparing fullerenes containing the isotopes {sup 212}Pb, {sup 212}Bi, {sup 213}Bi, and {sup 177}Lu are described. None of these endohedral fullerenes had ever previously been prepared, and all of these radioisotopes are actively under investigation for RIT. Additionally, the chemistry for derivatizing the radiofullerenes for water-solubility and a method for removing exohedral radionuclides are reported. The methods and chemistry developed during this CRADA are the crucial first steps for the development of fullerenes as a method superior to existing technologies for in vivo transport of radionuclides.« less

Fullerenes could potentially play a valuable role in radioimmunotherapy by more stably encapsulating radionuclides, especially where conventional chelation chemistry is inadequate due to the physical and/or chemical properties of the radionuclide. One of the therapeutically useful radionuclides that requires improved containment in vivo is 212Pb (tau1/2 = 10.6 h), the beta-emitting parent to alpha-emitting 212Bi (tau1/2 = 60.6 min). Myelotoxicity resulting from the accumulation of 212Pb in the bone marrow has limited the use of this radionuclide despite its favorable decay characteristics. In this work, 212Pb@C60 and its malonic ester derivatives were prepared for the first time by allowing the 212Pb to recoil into C60 following alpha-decay from its parent, 0.15-s 216Po, generated in situ from the decay of 224Ra (tau1/2 = 15 days). Repeated washing of the organic phase containing the 212Pb@C60 malonic esters with challenge solutions containing cold Pb2+ ions demonstrated that some of the 212Pb could not be exchanged and was apparently inside of the fullerenes. Malonic esters of endohedral alpha-emitting 213Bi (tau1/2 = 45 min) fullerenes were prepared by an analogous procedure. Following acidification of the esters, a preliminary biodistribution study in mice was performed with the untargeted water-soluble radiofullerenes. It was found that 212Pb did not accumulate in bone after being administered as an endohedral fullerene, in contrast to results with polyhydroxylated radiofullerenes and conventional polyaminocarboxylate chelators for 212Pb. The results indicate that 212Pb is held more tightly in the fullerene than in other methods and suggest that fullerenes may have an important role in the targeted delivery of 212Pb.

In a theoretical interpretation of observational data from the neutron star EXO 0748-676, Ozel concludes that quark matter probably does not exist in the centre of neutron stars. However, this conclusion is based on a limited set of possible equations of state for quark matter. Here we compare Ozel's observational limits with predictions based on a more comprehensive set of proposed quark-matter equations of state from the literature, and conclude that the presence of quark matter in EXO 0748-676 is not ruled out.

Ozel, in a recent reanalysis of EXO 0748-676 observational data (astro-ph/0605106), concluded that quark matter probably does not exist in the center of compact stars. We show that the data is actually consistent with the presence of quark matter in compact stars., 4 pages, LaTeX; New title and overall rewrite to reflect version published in Nature. Conclusions unchanged