cssi/SciSciGPT-SciSciNet huggingface dataset:
Pattern of cerebral hypoperfusion in Alzheimer's disease and mild cognitive impairment measured with arterial spin-labeling MR imaging: Initial experience

Abstract Purpose To prospectively determine if pulsed arterial spin-labeling perfusion magnetic resonance (MR) imaging depicts regional cerebral hypoperfusion in subjects with Alzheimer's disease (AD) and mild cognitive impairment (MCI), compared with perfusion in cognitively normal (CN) subjects, that is consistent with results of fluorodeoxyglucose (FDG) positron emission tomography (PET) and hexamethylpropyleneamine oxime (HMPAO) single photon emission computed tomography (SPECT) studies of similar populations. Materials and methods Institutional review board approval and informed consent were obtained. 20 subjects with AD (13 men, 7 women; mean age = 72.9 years), 18 with MCI (9 men, 9 women; mean age = 73.3 years), and 23 CN subjects (10 men, 13 women; mean age = 72.9 years) underwent arterial spin-labeling and volumetric T 1 -weighted structural MR imaging. Perfusion images were coregistered to structural images, corrected for partial volume effects (PVEs) with information from the structural image to determine tissue content of perfusion voxels, and normalized to a study-specific template. Analyses of perfusion differences between groups, with and without corrections for PVEs, were performed on a voxel-by-voxel basis with a one-tailed fixed-effects analysis of covariance model adjusted for age. In addition, tests were performed with and without accounting for global perfusion. Results The AD group showed significant regional hypoperfusion, compared with the CN group, in the right inferior parietal cortex extending into the bilateral posterior cingulate gyri ( P P P = 0.007). When PVEs from underlying cortical gray matter atrophy were accounted for, the AD group still showed hypoperfusion in the right inferior parietal lobe extending into the bilateral posterior cingulate gyri ( P P = 0.003) and right ( P = 0.012) middle frontal gyri. With a more liberal voxel-level threshold of P P = 0.046), similar to the region of greatest significance in the AD group. Conclusion Arterial spin-labeling MR imaging showed regional hypoperfusion with AD, in brain regions similar to those seen in FDG PET and HMPAO SPECT studies of similar populations; this hypoperfusion persists after accounting for underlying cortical gray matter atrophy.
Spectral analysis of EEG from families

Electroencephalographic (EEG) activity was obtained under eyes open and eyes closed conditions from ten families, each consisting of a biologically related father, mother and two children. Spectral power (microV2) and mean frequency (Hz) measures from the delta, theta, alpha-1, alpha-2, beta-1, and beta-2 bands were computed for each family member. Non-family controls were constructed from the real family data by randomly pairing non-related individuals with one another, and correlations between the analogous individuals were also computed. The correlations for spectral power between family groups were greater than those obtained from the non-families for theta, alpha, and beta band power. The correlations for mean frequency between family members were greater than those of the non-families for the delta, theta, and alpha bands, although these were not as robust as the spectral power findings. In general, few family membership effects were found for the eyes open/closed or electrode site conditions. The results support findings from twin studies that suggest EEG characteristics are determined at least in part by genetic factors.
In vivo distribution of a vaginal gel: MRI evaluation of the effects of gel volume, time and simulated intercourse

A microbicide is designed to coat the vaginal epithelium and prevent transmission of HIV. Complete coverage is desired for optimal protection. In vivo factors affecting coverage have not yet been studied. This randomized crossover trial evaluates the effect of gel volume and patient activity upon vaginal epithelial coating. Gynol II gel was mixed with a magnetic resonance imaging (MRI) contrast agent. Ten women self-inserted, on separate visits, 3 or 5 mL of gel and underwent serial MRI scanning both before and after simulated intercourse. Gel spread was dependent upon time and volume. There was modest spread during the first hour and greater spread 6 h after insertion. Five milliliters of gel resulted in statistically significantly greater coverage immediately following insertion, within the first 30 min and at 6 h after insertion. Simulated intercourse greatly enhances gel spread. After simulated intercourse, the distribution of the gel at each volume was similar. Less leakage of gel was reported with the smaller volume.
Glycosylated DOTA−α-Melanocyte-Stimulating Hormone Analogues for Melanoma Targeting: Influence of the Site of Glycosylation on in Vivo Biodistribution

α-Melanocyte-stimulating hormone (α-MSH) is known to bind to the melanocortin receptor 1 (MC1R) which is overexpressed on melanotic and amelanotic melanoma cells. α-MSH analogues are potential candidates for specific targeting of melanoma metastases. Several linear and cyclic radiolabeled MSH peptides have been designed and tested in the past, showing both high affinity for the MC1R in vitro and good incorporation in tumor xenografts in vivo. However, considerable kidney reabsorption of the radiopeptides could not be avoided. With the aim to increase the tumor-to-kidney ratio, we synthesized six glycosylated derivatives of NAPamide, an α-MSH octapeptide analogue with high tumor selectivity and coupled them to the chelator DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). The peptides were evaluated in vitro for MC1R binding and bioactivity and, after labeling with 111In, for in vitro cellular uptake and in vivo tissue distribution in mice carrying B16F1 melanoma tumors. The glycopeptides sh...
The safety and effectiveness of human growth hormone using pharmacological dosing

Human growth hormone in currently recommended dosage is effective in many short children, irrespective of their endogenous growth-hormone status. This suggests that present dosing is pharmacological rather than physiological. As for any drug, issues of safety should be of paramount concern. Reassuring short-term data with pharmacological dosing or long-term data with replacement dosing cannot guarantee the ultimate safety of this form of therapy. The risk of future malignancy should be of particular concern. Poorly growing children without classic (severe) growth-hormone deficiency constitute an increasing proportion of children treated with human growth hormone. There are no satisfactory criteria for the diagnosis of neurosecretory growth-hormone dysfunction. The closer to puberty these children are treated, the less likely it is that there will be benefits in terms of increased final height. Recommendations as to a 'safety first' approach to growth-hormone treatment are given. A multicentre controlled trial is urgently needed to establish the benefits of treating children with neurosecretory growth hormone dysfunction.
Autoradiography of long-term RNA metabolism in rabbit neurones.

ATTEMPTS at studying the metabolism of RNA in neurones by the usual techniques of autoradiography have been hampered because parenteral injections of RNA precursors show very little uptake in the brain, while injections directly into the cerebrospinal fluid produce uneven distribution1,2.
Understanding Infidelity: Pitfalls and Lessons for Couples Counselors:

Infidelity is a serious problem with serious consequences for couples and creates substantial obstacles for couples counselors. At the same time, it is the most often cited reason that couples come for counseling. The good news is that couples counselors can be effective in these areas, but not without understanding the emotional, mental, and physical complexity of infidelity. Unfortunately, many couples counselors do not feel adequately prepared to handle the subject of infidelity. There are several “pitfalls” into which counselors commonly fall. By understanding the relevant research on the effectiveness of couples counseling approaches and paying attention to a counselor's own personal reactions, a practitioner can help couples navigate the difficult, painful emotions that stem from infidelity.
Structured Home Study Evaluations: Perceived Benefits of SAFE Versus Conventional Home Studies

Structured decision-making methods are gaining ascendance in child welfare services, in which professionals combine standardized methods of data collection and analysis with clinical judgments. This study measures professionals’ perception of a new approach to home study assessments, the Structured Analysis Family Evaluation (SAFE). Findings indicate that workers favor the use of SAFE overall. Less experienced workers are especially positive about SAFE, while more experienced workers and supervisors tend to be less positive. State-by-state differences also emerged. Open-ended responses offer areas for clarification, training, and potential improvement.
Subsonic jet noise reduction by microjets with various injection port geometries

The effect of injecting tiny secondary jets (‘∝jets’) on the radiated noise from a subsonic primary jet is studied experimentally. The ∝jets are injected through ports near the nozzle exit with variable port geometry, driving pressure, and yaw angle. A small but clear noise reduction is observed that improves with increasing ∝jet pressure. It is found that smaller diameter ports with higher driving pressure, but involving less thrust and mass fraction, can produce better noise reduction. The present data are compared with data from other investigations on the subject in an attempt to correlate the noise reduction with the operating parameters. The results appear to indicate that the OASPL reduction at a shallow angle correlates with the ratio of the density-velocity-diameter product of the ∝jet to that of the primary jet.
Galvanic Responses of Preschool Children

*Received for publication by Helen Thompson Woolley of the Editorial Board, January 13, 1930.
HOT-WATER QUARANTINE TREATMENT TO CONTROL FRUIT FLIES IN MANGOES IMPORTED INTO THE UNITED STATES FROM PERU

Heated water was tested as a quarantine treatment to control infestations of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann); West Indian fruit fly, Anastrepha oblique (Macquart); A. fraterculus (Wiedemann), and A. distincta Greene in mango, Mangifera indica L., imported from Peru. Immersing infested fruit for 10-70 min at 46.1 ± 0.25°C reduced the number of surviving pupae that developed from treated larvae. Probit analysis of the data estimated immersion times needed to reach 99.9968% (Probit 9) mortality as 76.1 min for C. capitata , 113.4 min for A. oblique , 75.6 min for A. fraterculus , and 65.8 min for A. distincta . Large-scale confirmatory tests for C. capitata and A. oblique resulted in no survivors based on normal appearing pupae when 148,925 C. capitata in 3,710 infested mangoes and 122,417 A. oblique in 4,118 infested mangoes were immersed in water at 46.1 ±0.25°C for 90 min.
The Ara Pacis Augustae: Visual Rhetoric in Augustus' Principate

Scholars of rhetoric have veered away from non-traditional rhetorical artifacts in the classical period. In this article I examine the Ara Pacis Augustae, Altar of Augustan Peace, as one such overlooked rhetorical artifact. I argue the altar, although constructed as a war monument, shapes public memory to persuade the people of Rome to accept the dynastic succession of Augustus's heir. In addition, I show a variety of rhetorical theories operate on the altar in visual form including amplification, imitation, and enthymeme. Ultimately I contend that by focusing on non-traditional rhetorical artifacts, we can deepen our understanding of the rhetorical tradition in a period in which rhetoric is generally believed to have faded away.
MIGRACIONES Y POBREZA

This essay argues that political efforts toward eradicating poverty in the developing countries should take precedence over political efforts to get more poor and oppressed persons admitted into our affluent societies. Efforts of both kinds are directed at morally worthy goals. But the former efforts are likely to be far more effective than the latter.
Direct observation of hydration of TiO2 on Ti using electrochemical AFM: freely corroding versus potentiostatically held

Abstract Hydration of titanium/titanium oxide surfaces under freely corroding and potentiostatically held conditions has been characterized using electrochemical atomic force microscopy (EC AFM). In contrast to conventional high vacuum techniques, AFM enables measurement of morphological surface structure in the in situ hydrated state. Electrochemical probes in the imaging environment further enable acquisition of electrical characteristics during AFM imaging. Experiments were performed on etched, electropolished commercially pure titanium. As noted by direct observation and corroborated by power spectral density (Fourier analysis) measurements, oxide domes cover the titanium surface and grow laterally during hydration. Applied potential altered the growth rate. Under open circuit potential conditions, growth proceeded approximately six times faster than under a −1 V applied voltage ( 1098±52 nm 2 / min ± versus 184.84±19 nm 2 /min). Film growth increased electrical resistance and lowered interfacial capacitance based on step polarization impedance spectroscopy tests.
The importance of problem-driven research: Bringing Wachtel's argument into the present

Abstract There is no one best way to do psychological research. Rather, the “best” way depends on the fit to the problem. Research should be problem-driven rather than method-driven. Psychologists sometimes envy certain natural scientists, and over-reward those who do research with a surface structure more like that of research in the natural sciences, leading to sub-optimal progress in the field.
Hippocampal units during orienting and arousal in rabbits

Abstract Unit responses were recorded in CA1 of the hippocampus of awake restrained rabbits concurrently with cortical EEG, nuchal EMG and ECG. Changes in rate of unit activity were nonlinearly related to changes in arousal level, whether the latter occurred spontaneously or were evoked by novel stimuli. These data were discussed in relation to models proposing hippocampal roles in orienting and modulation of arousal.
Periodicity in the isotope chemistry of hydrogen

Abstract Periodicities and regularities are established among the deuterium to protium isotopic reduced partition function ratios, ln(s/s′)f, of 39 diatomic and 19 polyatomic hydrides. It is shown that ln(s/s′)f for diatomic hydrides can be correlated with the position in the periodic table of the element X in the hydride HX. A similar analysis is made for the contributions from X—H stretching motion in the polyatomic hydrides HnX. It is shown that the contributions from stretching motions to ln(s/s′)f in diatomic and polyatomic molecules are a linear function of the square root of the stretching force constants. The contributions from bending coordinates to ln(s/s′)f depend on both the molecular structure of the hydride and the bending force constant. Simple correlations are established for the bending contributions to ln(s/s′)f for the hydrides of the elements belonging to a common group in the periodic table. Four periodic rules of the isotope chemistry of hydrogen summarize and classify the data on the isotopic partition function ratios and the isotopic differences in free energies of formation of hydrides.
Gel electrophoretic and density gradient analysis of the (K+ + Ca2+)-ATPase and the (Na+ + K+)-ATPase activities of cardiac membrane vesicles.

The two major ATPase activities of intact and leaky cardiac membrane vesicles (microsomes) were characterized with respect to ionic activation requirements. The predominant ATPase activity of intact vesicles was (K+ + Ca2+)-ATPase, an enzymic activity localized to sarcoplasmic reticulum, whereas the predominant ATPase activity of leaky, sodium dodecyl sulfate-pretreated vesicles was (Na+ + K+)-ATPase, an enzymic activity localized to sarcolemma. The (K+ + Ca2+)-ATPase activity was stimulated 4- to 5-fold by 100 mM K+ in the presence of 50 μM Ca2+. Phosphorylation of the (K+ + Ca2+)-ATPase of intact vesicles with [γ-32P]ATP was Ca2+ dependent, and monovalent cations including K+ increased the level of [32P]phosphoprotein by up to 50% when phosphorylation was measured at 5°C. After the intact vesicles were treated with SDS (0.30 mg/ml), (K+ + Ca2+)-ATPase was inactivated, as was Ca2+-dependent 32P incorporation. The monovalent cation-stimulated ATPase activity of the particulate residue (SDS-extracted membrane vesicles) displayed the usual characteristics of ouabain-sensitive (Na+ + K+)-ATPase and the activity was increased 9- to 14-fold over the small amount of patent (Na+ + K+)-ATPase activity of intact membrane vesicles. 32P incorporation by the (Na+ + K+)-ATPase of SDS-extracted vesicles was Na+ dependent, and Na+-stimulated incorporation was increased 7- to 9-fold over that of intact vesicles. Slab gel polyacrylamide electrophoresis of both intact and SDS-extracted crude vesicle preparations revealed at least 40 distinct Coomassie Blue-positive protein bands and provided evidence for a possible heterogeneous membrane origin of the vesicles. Periodic acid-Schiff staining of the gels revealed at least two major glycoproteins. Simultaneous electrophoresis of the 32P-intermediates of the (K+ + Ca2+)-ATPase and the (Na+ + K+)-ATPase in the same gels did not resolve the two enzymes clearly. With sucrose gradient centrifugation of intact membrane vesicles, it was possible to physically resolve the two ATPase activities. Latent (Na+ + K+)-ATPase activity (unmasked by exposing the various fractions to SDS) was found in the higher regions of the gradient, whereas (K+ + Ca2+)-ATPase activity was primarily in the denser regions. A reasonable interpretation of the data is that cardiac microsomes consist of membrane vesicles derived both from sarcolemma and sarcoplasmic reticulum. (Na+ + K+)-ATPase is localized to intact vesicles of sarcolemma but is mainly latent, whereas (K+ + Ca2+)-ATPase is mostly patent and is localized to vesicles of sarcoplasmic reticulum.
Manganese-induced toxicity in normal and human B lymphocyte cell lines containing a homozygous mutation in parkin

Mutations in the parkin gene are linked to development of juvenile onset of Parkinson’s disease and recent studies have reported that parkin can protect against increased oxidative stress and mitochondrial dysfunction caused by a variety of oxidative and toxic insults. Overexpression of parkin has also been reported to selectively protect dopaminergic neurons from Mn toxicity. Accordingly, in this paper we compare the effect that mutations in parkin have on Mn toxicity and associated apoptotic signals in normal and human B lymphocyte cell lines containing a homozygous mutation in the gene. Results of these studies reveal that Mn toxicity was similar in both control and mutant parkin lymphocyte cells indicating that cell death caused by Mn was not altered in cells devoid of parkin activity. In contrast, Mn did inhibit mitochondrial function to a greater extent in cells devoid of active parkin as indicated by a decrease in ATP production although mitochondrial membrane potential was essentially unaffected. Consistent with inactive parkin influencing the Mn response is the observation of increased activity in the down-stream apoptotic signal, caspase 3. In summary, results reported in this paper demonstrate that mutations in parkin can lead to functional changes in potential signaling processes known to provoke Mn toxicity. The selectivity and magnitude of this response, however, does not necessarily lead to cell death in lymphocytes which are devoid of dopamine.
Dietary Supplements and Sports Performance: Amino Acids

This is the third in a series of six articles to discuss the major classes of dietary supplements (vitamins; minerals; amino acids; herbs or botanicals; metabolites, constituents/extracts, or combinations). The major focus is on efficacy of such dietary supplements to enhance exercise or sport performance.
A 0.13-/spl mu/m CMOS Ultra-Low Power Front-End Receiver for Wireless Sensor Networks

This paper presents an ultra-low power monolithic CMOS RF receiver, consisting of current re-use common gate LNA with inductive feedback gm-boosting, and followed by balanced I/Q mixers. The receiver is fabricated in a 0.13-mum CMOS digital process operating at 2.45 GHZ. The measurement results show that the RF receiver achieves a gain of 20 dB and a noise figure of 7.5 dB at 2 MHz. Input 1-dB compression point is -19 dBm and IIP3 is -10 tlBm, with 0.4 mA total current consumption from a 1.5-V supply.
Bounds and Protocols for a Rate-Constrained Relay Channel

In this correspondence, a relay rate-constrained variation of the three-node relay channel is introduced and studied. In the rate-constrained relay channel, the relay cannot reliably decode or encode beyond a rate constraint R macr. A cut-set upper bound, and rate-constrained variations of decode-and-forward and estimate-and-forward protocol are derived. It is observed that relative performance of the unconstrained protocols does not predict relative performance of the constrained protocols; that is, estimate-and-forward almost always offers superior performance for small rate constraints. A new metric, denoted as the relay efficiency, measures the slope at which the relay channel rate increases over the relay-less channel. While the cut-set upper bound has a relay efficiency of one for the Gaussian relay channel at R macr = 0, the two new protocols do not. Finally, it is shown that an effective relay rate constraint can be computed for general relay protocols. To demonstrate this concept, a Markovian amplify-and-forward protocol, in which the relay does not perform any explicit encoding or decoding, is examined and compared to the introduced rate-constrained protocols.
First responder information flow simulation: a tool for technology assessment

New information technology is becoming available for first responders at a rapid rate. Often this new technology comes with not only new capabilities but also a high price tag. Policy makers and emergency managers need a way to assess which portfolio of technologies achieves the greatest benefit at a minimal cost. Assessing these technologies in a real world setting not only takes a long time but is also often cost-prohibitive. Thus, using computer simulation to assess the benefits of new technologies would yield significant insight into the usefulness of new technologies in a cost and time-efficient manner. A computer simulation combining an agent-based architecture and GIS information called Disaster Response Information Flow and Technology Simulator (DRIFTS) is developed to model the information flow in a disaster setting. DRIFTS, combined with a response surface methodology, can be used to assess different types of information technologies for disaster response.
Rhythmic expression of cytochrome P450 epoxygenases CYP4x1 and CYP2c11 in the rat brain and vasculature.

Mammals have circadian variation in blood pressure, heart rate, vascular tone, thrombotic tendency, and cerebral blood flow (CBF). These changes may be in part orchestrated by circadian variation i...
Cyclic Trophic Relationships of Fishes in an Unpolluted, River-Dominated Estuary in North Florida

Regular patterns in seasonal occurrence of dominant fishes were observed over a six-year period in the Apalachicola estuary of north Florida. Examination of potential physico-chemical and biological community determinants has led to the hypothesis that trophic relationships and underlying physical-biological inter-actions structure this estuarine fish community. Six species (Anchoa mitchilli, Micropogonias undulatus, Leiostomus xanthurus, Cynoscion arenarius, Brevoortia patronus, and Bairdiella chrysura) comprise 85% of the trawl-susceptible fishes in the Apalachicola system, and each is characterized by distinctive seasonal abundances and trophic spectra. Two benthic omnivores (Micropogonias and Leiostomus) exhibit high spatial and temporal overlap but differ in prey type and size. These two species utilize the estuary subsequent to high river discharge/detritus input and concurrent with maximum benthic standing crops. Two epibenthic carnivores (Cynoscion and Bairdiella) also use the estuary but differ in times of peak abundances and in prey types. Two planktivores (Brevoortia and Anchoa) also frequent the estuary but during different seasons (spring and fall, respectively), yet neither cooccurs with the maximum zooplankton standing crop (summer). Anchoa is prevented from doing so by the piscivorous Cynoscion population. Thus, regular seasonal progressions of dominant fishes are linked to available trophic resources, competition, and predation, which are in turn dependent upon such factors as river flow, detrital input, plankton production, and offshore processes. The data indicate that the trophic organization of the Apalachicola estuary is highly structured and is not simply the result of a series of physically forced events superimposed over a network of trophic opportunism.
Characteristic impedance of a soliton-bearing nonlinear transmission line

The wave reflection and transmission in a nonlinear LC transmission line terminated with a resistive load are studied numerically. It is found that the soliton signals in the strongly nonlinear transmission line are almost perfectly absorbed by the linear resistor terminating the transmission line.
An unusual and challenging case of HIV-associated primary CNS Lymphoma with Hodgkin-like morphology and HIV encephalitis

HIV-associated primary CNS lymphomas are well-recognized, almost exclusively EBV-driven neoplasms with poor clinical prognosis. We report a challenging, atypical case of an HIV-associated lymphoproliferative disorder with unusual morphologic features reminiscent of Hodgkin Lymphoma, accompanied by HIV encephalitis. A 52-year-old male presented with acute seizures after seven months of progressive neurocognitive decline that was clinically diagnosed as progressive supranuclear palsy. Clinical work-up revealed HIV infection along with two ring-enhancing lesions in the brain on MRI, and negative CSF EBV testing. Subsequent biopsy showed well-demarcated hypercellular regions in the brain comprised of scattered Reed-Sternberg-like cells in a background of small to medium-sized lymphocytes exhibiting focal angiocentricity and geographic necrosis. The atypical cells were positive for CD20, EBV, and CD79a, and negative for CD45, GFAP, CD15, CD30, and p24. These cells were admixed with numerous CD68-positive cells. The adjacent brain showed classic features of HIV encephalitis with perivascular, CD68 and p24-positive multinucleated giant cells. This case illustrates several diagnostic pitfalls in the work-up of HIV-associated brain lesions, as well as reporting a unique histomorphology for an HIV-related primary CNS lymphoproliferative disorder.
Toggles and oscillators: new genetic circuit designs.

Two recent papers report the de novo design of a functioning biological circuit using well-characterized genetic elements.(1,2) Gardner et al. designed and constructed a genetic toggle switch while Elowitz and Leibler built an oscillating genetic circuit. Both circuits were designed with the aid of mathematical models. These papers demonstrate progress towards the unification of theory and experiment in the study of genetic circuits. Comparison of the predicted and observed behavior of the circuits, however, shows that the models explain only some of the circuits' properties. Further study of the observed behaviors not predicted by the model would lead to new insight into the properties of genetic networks. BioEssays 22:507-509, 2000.
Triptycene-like behaviour of tertiary 9,10-dihydro-9-amthrols

Abstract Secondary alcohols in the 9,10-dihydro-9-anthrol series frequently undergo acid-catalyzed elimination and substitution reactions more rapidly than do corresponding tertiary alcohols - a phenomenon attributed to predominant existence of the tertiary alcohols in triptycene-like conformations with the hydroxy groups in pseudoequatorial positions.
Differentiation in Acanthamoeba castellanii is induced by specific monoclonal antibodies

Monoclonal antibodies that bind a large molecular weight plasma membrane protein of Acanthamoeba castellanii cause the cells to differentiate. A different monoclonal antibody that binds specifically to the major plasma membrane protein has no effect upon cell division or differentiation. The induction of differentiation by the monoclonal antibodies requires a bivalent attachment, more than a single binding cycle of the antibody to the plasma membrane protein, does not require cell-cell contact, and appears to be mediated by an inhibition of pinocytosis. These results suggest one of two alternatives: either (1) this free living amoeba possesses a cell surface receptor that serves to initiate the differentiation process when stimulated, or (2) the specific plasma membrane antigen for the differentiation-inducing monoclonal antibodies is an essential component of the pinocytotic mechanism. While it seems more likely on the basis of available evidence that we are observing the biological effects of a cell surface receptor, either of the two alternative circumstances open up investigative areas of large significance.
The use of PET and knockout mice in the drug discovery process.

Abstract Although [15O]H2O, 2-[18F]fluoro-2-deoxyglucose (FDG) and other radioligands for low-density receptors and enzymes have been used in drug discovery and drug development, the impact on the pharmaceutical industry, to date, has been anecdotal. As new chemical entities are developed, radiotracers that aid in characterizing these drugs need to be developed rapidly to have an impact on the development process. The combined use of positron emission tomography (PET) and gene-manipulated animal models to validate radioligands quickly holds great promise for accelerating the discovery process
Alloying Effects of Cosputtered Gold-Platinum Thin Films on the Oxygen Reduction Reaction in Acidic Electrolyte

A better understanding of the effects of alloying Pt with Au on the oxygen reduction reaction (ORR) was achieved in this study. Recent investigations of carbon-supported Au-Pt nanoparticle catalysts have shown enhanced response for the ORR with respect to pure Pt nanoparticles. These results were reported to be due to homogeneous mixing of Au and Pt atoms that was accomplished in nanoscale particles, effectively removing the miscibility gap inherent in the equilibrium phase diagram. In this study, cosputtering of Au and Pt is used to form 350 nm thick films to achieve homogeneous mixing without nanoparticle geometries, thereby isolating the effects of alloying from nanoparticle effects. ORR activity and stability at these electrodes are investigated via cyclic voltammetry in O 2 -saturated 0.5 M H 2 SO 4 under oxidizing potentials. Cosputtering yielded solid solution alloys throughout the entire composition range as shown by X-ray diffraction results. Furthermore, as-deposited near-surface compositions determined by X-ray photoelectron spectroscopy indicated that extensive Au surface segregation was avoided by room-temperature deposition. Metastable compositions within the miscibility gap, explicitly Pt 21 Au 79 , Pt 43 Au 57 , and Pt 59 Au 41 , were found to be significantly more electrocatalytic for O 2 reduction than the pure Pt film, although Pt 43 Au 57 and Pt 59 Au 41 rapidly lost catalytic activity with subsequent potential sweeps.
Insulin resistance and vascular function

It has become clear that amongst its many actions insulin is also a vasoactive hormone. Its effect to cause endothelial-nitric oxide-dependent vasodilation is physiologic and dose-dependent. Recent data suggest that insulin's metabolic and vascular actions are closely linked. Indeed, insulin resistant states, which by definition, exhibit diminished insulin-mediated glucose uptake into peripheral tissues also display impaired insulin mediated vasodilation as well as impaired endothelium dependent vasolidation to the muscarinic receptor agonist acetylcholine. Free fatty acids are elevated in states of insulin resistance and also cause endothelial dysfunction along with impaired insulin-mediated vasodilation. Thus, a picture is emerging linking insulin action in peripheral tissues to its action in endothelium. More recent data suggest that insulin signaling mechanisms in peripheral tissues and endothelium may be shared. Thus mechanisms causing insulin resistance via defects in insulin signaling might be expected to be manifest in both tissues. The protective action of nitric oxide and healthy endothelial function are critical to prevent atherosclerotic vascular disease. If follows that endothelial dysfunction associated insulin resistance through common defects in insulin signaling presents a parsimonious mechanism to account for the increased risk of cardiovascular disease associated with insulin resistance.
Digital filtering using pseudo fermat number transforms

In this paper pseudo Fermat number transforms (FNT's) are discussed. These transforms are defined in a ring of integers modulo an integer submultiple of a pseudo Fermat number, and can be computed without multiplications while allowing a great flexibility in word length selection. Complex pseudo FNT's are then introduced and are shown to relieve some of the length limitations of conventional Fermat number transforms (FNT's). These transforms, which under certain conditions can be computed via fast transform algorithms allow the implementation of digital filters with better efficiency and accuracy than the fast Fourier transform (FFT).
Topological Proof of Cartan’s Theorem

We will give another proof of Cartan’s Theorem 16.5. Since this was already proved in the last chapter, the reader can skip this chapter with no loss of continuity. As a by-product of this second proof, we will obtain some topological insight into the “flag manifold” G/T, where T is a maximal torus in the compact Lie group T, a topic that we will take up in the final chapter.
Rationale for and dimensions of impact surfaces for biofidelity tests of different sizes of frontal and side impact dummies.

This paper describes how the biofidelity impact response corridors that were used to develop the Hybrid III family of dummies were established by scaling the various biofidelity corridors that were defined for the Hybrid III mid-size, adult male dummy. Scaling ratios for the responses of force, moment, acceleration, velocity, deflection, angle, stiffness and time were also developed using dimensions and masses that were prescribed for these dummies. In addition, an elastic modulus ratio for bone was used to account for the differences between child and adult bone elastic properties. A similar method is being used by ISO/TC22/SC12/WG 5 in order to develop biofidelity guidelines for a family of side impact dummies based on scaling the biofidelity impact response corridors that are prescribed for WorldSID, which is a mid-size adult male dummy. While the various biomechanical impact response requirements for the Hybrid III family of dummies and the WorldSID are documented in literature, the scaling used to prescribe the dimensions of the impact surfaces that are used for the various biofidelity tests for various sizes of dummies are not documented. This paper describes the rationale for how these impact surfaces should be scaled, gives the scaling equations, and gives the dimensions of the impact surfaces that should be used for the various biofidelity tests of the different sizes of adult and child dummies. It is recommended that the impact surfaces be scaled for the test subject size so that the data can be appropriately normalized to any size subject for future post-mortem human subject (PMHS) and human volunteer tests that are conducted to define impact biofidelity guidelines.
Highly Stable Operation of Lithium Metal Batteries Enabled by the Formation of a Transient High-Concentration Electrolyte Layer

Lithium (Li) metal has been extensively investigated as an anode for rechargeable battery applications due to its ultrahigh theoretical specific capacity and the lowest redox potential. However, significant challenges including dendrite growth and low Coulombic efficiency are still hindering the practical applications of rechargeable Li metal batteries. It is demonstrated that long-term cycling of Li metal batteries can be realized by the formation of a transient high-concentration electrolyte layer near the surface of Li metal anode during high rate discharge process. The highly concentrated Li+ ions in this transient layer will immediately be solvated by the available solvent molecules and facilitate the formation of a stable and flexible solid electrolyte interphase (SEI) layer composed of a poly(ethylene carbonate) framework integrated with other organic/inorganic lithium salts. This SEI layer largely suppresses the corrosion of Li metal anode attacked by free organic solvents and enables the long-term operation of Li metal batteries. The fundamental findings in this work provide a new direction for the development of Li metal batteries that could be operated at high current densities for a wide range of applications.
Chronic lymphocytic leukemia cells diversify and differentiate in vivo via a nonclassical Th1-dependent, Bcl-6–deficient process

Xenografting primary tumor cells allows modeling of the heterogeneous natures of malignant diseases and the influences of the tissue microenvironment. Here, we demonstrate that xenografting primary chronic lymphocytic leukemia (CLL) B lymphocytes with activated autologous T cells into alymphoid mice results in considerable CLL B cell division and sizable T cell expansion. Nevertheless, most/all CD5+CD19+ cells are eventually lost, due in part to differentiation into antibody-secreting plasmablasts/plasma cells. CLL B cell differentiation is associated with isotype class switching and development of new IGHV-D-J mutations and occurs via an activation-induced deaminase-dependent pathway that upregulates IRF4 and Blimp-1 without appreciable levels of the expected Bcl-6. These processes were induced in IGHV-unmutated and IGHV-mutated clones by Th1-polarized T-bet+ T cells, not classical T follicular helper (Tfh) cells. Thus, the block in B cell maturation, defects in T cell action, and absence of antigen-receptor diversification, which are often cardinal characteristics of CLL, are not inherent but imposed by external signals and the microenvironment. Although these activities are not dominant features in human CLL, each occurs in tissue proliferation centers where the mechanisms responsible for clonal evolution operate. Thus, in this setting, CLL B cell diversification and differentiation develop by a nonclassical germinal center-like reaction that might reflect the cell of origin of this leukemia.
Method of controllable 3D manipulation for single virus

The 3D manipulation of single virus has great significance to the researches of molecular and cellular immunology in a bottom-up way.However,this 3D manipulation has not been well demonstrated due to the limitations of operation tools and methods.In this paper,we carried out a detailed study of controllable single virus 3D manipulation based on the nanorobot developed from the Atomic Force Microscope(AFM),it mainly concludes the method of preparing high uniform and scattered virus sample,the real-time sensing strategy of 3D manipulation results based on local scan technique,and the implementation skills of releasing single virus in a certain location controllably.The experimental results show that single virus can not only be controllably picked up or released in certain place,but can be constructed into 3D structure successfully with the method we proposed,which verifies the validity and effectiveness of the proposed method,and further provides a feasible way for the study of bottom-up cellular immunology.
Assessment of carotid artery stenosis by MR angiography: comparison with x-ray angiography and color-coded Doppler ultrasound.

PURPOSE To compare magnetic resonance angiography (MRA) with duplex Doppler ultrasound (US) and x-ray angiography (XRA) in the evaluation of the carotid bifurcation. METHODS The carotid arteries of 61 patients were studied using MRA, US, or XRA; 31 of the patients underwent all three examinations. MRA included both 2D and 3D time-of-flight sequences. Internal and external carotid artery origins were graded normal, mild, moderate, severe, or critical stenosis, or complete occlusion by each of the three studies. RESULTS Spearman rank correlations of both internal and external carotid artery grades were 0.85 (MRA and XRA), 0.69 (MRA and US), and 0.73 (XRA and US). For internal carotid artery origins only, the correlations were 0.94 (MRA and XRA), 0.85 (MRA and US), and 0.82 (XRA and US). Of discrepancies in internal carotid artery interpretation greater than one grade, seven resulted from US error, three from MRA error, and one from XRA error. A 2-cm partially thrombosed aneurysm detected by US and MRA was missed by XRA. Of 16 possible ulcers on XRA, 11 were noted by MRA, none by US. CONCLUSIONS MRA and XRA are similar in assessment of carotid bifurcation stenosis. MRA, like US, permits direct visualization of plaque. This preliminary study suggests that MRA may be used to clarify equivocal findings of US, or replace XRA in presurgical planning.
Product Design Issues and Hospital Staffing

Nurses are leaving the field in ever increasing numbers. This article explores product design issues as they relate to the nursing shortage. It suggests ways for hospital administrators to use product design planning to offer jobs less susceptible to turnover and attrition. Information used in product design was collected from nurses through focus group discussions.
Protein Disulfide Isomerase Is Required for Fibrin Generation and Platelet Thrombus Formation In Vivo.

Thiol isomerases catalyze disulfide oxidation, reduction and isomerization, playing an important role during protein synthesis. Recent studies suggest a role for protein disulfide isomerase (PDI), a prototype of the thiol isomerase family, in platelet function and regulation of tissue factor activity (Essex and Li. Curr Drug Targets. 2006; Chen and Hogg. J Thromb Haemost. 2006). To determine the role of intravascular PDI during thrombus formation, PDI expression, platelet accumulation, and fibrin generation were monitored following laser-induced arteriolar injury in the mouse cremaster muscle by intravital fluorescence microscopy. PDI antigen exhibited a time-dependent increase in the developing thrombus after vessel wall injury and remained associated with the thrombus. Infusion of bacitracin, a non-specific inhibitor of thiol isomerases, into the circulation inhibited platelet thrombus formation and fibrin generation in a dose-dependent manner. Infusion of a function-blocking monoclonal antibody to PDI (RL90) into the circulation of a wild type mouse also resulted in dose-dependent inhibition of platelet accumulation and fibrin generation. To determine whether PDI inhibits fibrin formation by blocking tissue factor activation, or by preventing platelet activation and the development of the membrane surface that is required for assembly of the tenase and the prothrombinase complex in vivo, we explored fibrin formation in mice lacking protease-activated receptor-4 (Par4). Although there is no stable accumulation of platelets and no platelet activation, fibrin formation is normal in the Par4 null mouse (Vandendries et al, Proc Natl Acad Sci USA. 2007), suggesting that fibrin generation in the laser-induced vessel injury model is independent of platelet activation. Infusion of the function-blocking anti-PDI antibody (RL90) into the circulation of a Par4 null mouse prior to vessel wall injury inhibited fibrin generation. These results indicate that PDI is required to generate tissue factor in a form that leads to thrombin generation and fibrin formation during thrombus development and is required for thrombus formation.
Bacterial Infections of the Central Nervous System: Pathogenesis, Pathophysiology and Clinical Aspects

The central nervous system may be infected by a wide variety of bacteria, often as part of what is at first a bacteraemia but may later become a septicaemia, and sometimes as a result of extension from adjacent tissues. This chapter considers the pathophysiology of CNS bacterial infections and some of the host responses to these infections. In some cases an inadequate immune response may allow chronic infection to develop. Under other circumstances, notably meningitis, it is the host response that gives rise to tissue injury.
Exploring Complexities of Energy Options Through a Jigsaw Activity

Currently, the world’s transportation and commerce infrastructure is designed for coal, oil, and natural gas—energy resources, which are relatively easy to transport and store, can be used when desired, and have low production costs and high energy output. However, these fossil fuels are nonrenewable and have significant negative side effects. Therefore, we are in an energy crisis, and it may be argued that alternative energy sources (anything besides fossil fuels) should be used to help “solve” this crisis. However, factors such as economic and environmental costs and efficiency need to be considered when looking at the possibility of transitioning to these alternatives. The goal of the learning activity in this chapter is for students to learn about energy sources through a jigsaw activity so that they can explain the advantages and disadvantages of each. After completing the activity, students should be able to (1) define the concept of net energy ratio and explain how it impacts the viability of an energy source, (2) articulate the advantages and disadvantages of using different energy sources, (3) describe what an externality is and list ones associated with using fossil fuels, and (4) explain the challenges of replacing fossil fuels with alternative energy sources.
A Comparison of Von Willebrand Factor Indexes in Heartmate II Compared to Heartware Left Ventricular Assist Devices

Background: Von Willebrand factor (VWF) is a multimeric glycoprotein synthesized in endothelium and megakaryocytes. Elevated total VWF antigen has been associated with arterial thrombosis, while in patients with left ventricular assist devices (LVAD), loss of high molecular weight multimers is associated with spontaneous bleeding. We hypothesized that the lower rotational speed of the Heartware LVAD would be associated with less severe disruption of VWF. Methods: A total of 22 patients were included. We compared samples from a) 17 patients with Heartmate II LVAD (HM II), 76% male, median age 67 (54-73) years, 24% non-white, 45 (33-59) months after implant, with b) 5 patients with Heartware (HW) LVAD, all male, age 64 (59-65) years, 20% non-white, 27 (14-29) months after implant. All patients received warfarin. All HW patients took aspirin, while 82% of HM II patients took aspirin. Samples were analyzed for VWF antigen, activity, platelet function analyzer-100 collagen adenosine diphosphate closure time (PFA) and VWF multimers by gel electrophoresis. Multimers were assessed qualitatively and quantitatively by dividing mers > 15 by mers 2-15 (multimer ratio) and with a normalized multimer ratio (multimer ratio of patient / normal plasma control from the same gel). Results: Although flow rates did not differ significantly between HM II and HW, 5.2 (4.6-6.5) versus 4.3 (4.2-5.4) liters per minute respectively, rotational speeds were very different, mean 9472 versus 2680 rpms, p Conclusion: The lower rotational speed associated with the Heartware LVAD appears to produce less elevation of VWF antigen, and slightly less loss of VWF high molecular weight multimers compared to the Heartmate II LVAD. Additional studies are needed to describe whether or not lower pump thrombosis rates and rates of spontaneous bleeding are associated with these differences. Disclosures No relevant conflicts of interest to declare.