cssi/SciSciGPT-SciSciNet huggingface dataset:
Giant oscillator strength of excitons in bulk and nanostructured systems

Abstract Coherence phenomena in atomic vapors and crystals can have remarkable effects on emission and absorption of light, such as superradiance and “giant oscillator strength.” An exciton has intrinsic spatial coherence due to its existence in a periodic crystal and so exhibits giant oscillator strength, which may be described as the scaling of its optical transition rate with the number N of lattice sites in the coherence volume, at least for diameter ⪡ λ / 2 . If one can realize sufficient coherence volume, then ultrafast (e.g. picosecond) spontaneous radiative lifetimes are achievable, whereas no single atom can have a spontaneous radiative lifetime this short for visible light. We have been intrigued by the question of what sets the upper limit of oscillator strength as the coherent source size increases beyond a half wavelength of light in the medium. This paper discusses a semi-classical diffraction-based treatment which reduces to the Rashba–Gurgenishvili/Henry–Nassau r 3 -dependence for a very small source volume and includes the development toward forward-wave emission for a large coherent source volume in which the initial state is a plane-wave exciton.
Trypsin inhibitor activities of fibroblasts increase with age of donor and are unaltered in familial Alzheimer's disease.

Increasing evidence suggests that proteases and their inhibitors play an important role in the etiology of s-amyloidogenesis and Alzheimer's disease (AD). It is not clear, however, which proteases and protease inhibitors are responsible for the amyloidogenic proteolysis. Candidates include α-1-antichymotrypsin, inter-α-trypsin inhibitor, and forms of s-amyloid precursor protein (sPP) bearing Kunitz protease inhibitor domains. As one approach to this question, we have determined the trypsin inhibitor activity of fibroblast-like cells from 10 familial AD subjects and 20 controls. The activity was quantitated by measuring remaining trypsin activity of reaction mixtures containing trypsin and cell lysates using a fluorogenic substrate and two physiologically distinct populations of fibroblasts: proliferating cells (grown in the presence of 16% serum) and quiescent cells (maintained in 0.1% serum). The remaining trypsin activities of crude protein extracts from proliferating and quiescent AD cultures were not significantly different from those of controls. Perhaps of more general interest to the biology of aging, however, was our finding that protease inhibitor activity increased with the age of the donor (p = 0.005).
The effect of age on adenosine A1 receptor function in the rat heart

Adenosine is an important regulatory metabolite in the heart where it has a cardioprotective function. In the ventricle, the cardioprotective action of adenosine is mediated through the adenosine A1 receptor and inhibition of adenylyl cyclase. In order to investigate the effect of age on adenosine signal transduction in the heart, the effect of specific adenosine A receptor agonists on adenylyl cyclase activity was measured in crude cardiac ventricular membranes isolated from 1-, 6- and 24-month-old Fisher 344 rats. There were no differences in basal cyclase activity with age. Consistent with observations from other laboratories, isoproterenol- and forskolin-stimulated cyclase activity decreased with age. In addition, there was an age-related decline in the capacity of adenosine to inhibit stimulated adenylyl cyclase. The specific A1 adenosine receptor agonists, N6-cyclopentyladenosine (CPA) and N6-p-sulfophenuladenosine (SPA) inhibited isoproterenol- and forskolin-stimulated adenylyl cyclase activity in cardiac membranes from 1-month and 6-month-old rats; however, CPA and SPA did not inhibit adenylyl cyclase in membranes from 24-month-old rats. These data indicate that in addition to the age-related decline in beta-adrenergic receptor function with age, there is also a decrease in adenosine A; receptor-mediated responses. In contrast, carbachol acting through muscarinic receptors, caused the same inhibition of adenylyl cyclase at all ages. Therefore, the age-related decline in inhibitory signal transduction is specific to the adenosine A1 receptor. The age-related defect is probably at the level of the adenosine/receptor interaction and/or the receptor/guanine nucleotide binding protein interaction.
A snapshot of the low temperature stress transcriptome of developing rice seedlings ( Oryza sativa L.) via ESTs from subtracted cDNA library

Rice (Oryza sativa L.) is sensitive to chilling particularly during early seedling development. Given the biochemical complexity of tolerance mechanisms, genetic potential for this trait depends on highly coordinated expression of many genes. We used a simple cDNA subtraction strategy to develop Expressed Sequence Tags (ESTs) that represent an important subset of cold stress-upregulated genes. The 3,084 subtracted cDNA clones represent a total of 1,967 unigenes from 1,354 singletons and 613 contigs. As expected in the developing seedlings, genes involved in basic cellular processes, i.e., metabolism, growth and development, protein synthesis, folding and destination, cellular transport, cell division and DNA replication were widely represented. Genes with stress-related and regulatory functions comprised 23.17% of the total ESTs. These categories included proteins with known function in cellular defenses against abiotic (drought, cold and salinity) and biotic (pathogen) stresses, and proteins involved in developmental and stress response signalling and transcription. Based on the types of genes represented, tolerance mechanisms rely on precise integration of developmental processes with stress-related responses. A large fraction of the ESTs (38.7%) represents unknown proteins. This EST library is a rich source of cold stress-related genes, and supplements for other publicly available libraries for comprehensive analysis of the stress-response transcriptome.
Mergers involving academic medical institutions: Impact on academic radiology departments

During the past 10 years, there have been a number of large health care mergers in which at least one partner has been an academic medical center. This review summarizes the definitions, attributes needed for success, and reasons for failure of mergers. It then describes the various mergers and their outcomes and discusses the impact of the mergers on the involved radiology departments.
Utility of p16INK4a, CEA, Ki67, P53 and ER/PR in the differential diagnosis of benign, premalignant, and malignant glandular lesions of the uterine cervix and their relationship with Silverberg scoring system for endocervical glandular lesions.

Early detection of premalignant and malignant glandular lesions of the uterine cervix and their distinction from benign mimics is crucial but sometimes difficult. In this study, we investigated utility of expression of p16, CEA, Ki67, p53 and ER/PR in evaluating the benign, premalignant, and malignant glandular lesions of the uterine cervix. A total of 35 cervical cone or LEEP cases were collected including 14 adenocarcinoma in situ (AIS), 7 endocervical glandular dysplasia (EGD), and 14 benign mimics (BM). A histological score for each case according to the criteria proposed by Silverberg group was assigned independently by 4 pathologists. Formalin-fixed, paraffin-embedded sections were immunostained with p16, CEA, p53, Ki67, and ER/PR. Immunoreactivity was scored based on intensity (0 = none, 1 = mild, 2 = moderate, 3 = marked) and percentage of cells staining (0 = 40%). A comparison of histological scores and immunoscores in 3 diagnostic categories was analysed. The histological scores assigned independently by 4 pathologists were all equal or above 6 for AIS, between 3 and 5 for EGD, and equal or below 3 for BM. There was increased expression of p16 and CEA in EGD compared with BM (P < 0.05), with further increase in expression of these markers in AIS compared with EGD (P < 0.05). Ki67 expression was significantly increased in AIS compared to EGD (P < 0.05) as well as compared to BM (P < 0.05). Ki67 expression was only slightly increased in EGD as compared to BM. There was a loss of ER/PR in cervical AIS, but not in EGD. Our results indicate that the Silverberg scoring system is a useful tool in differential diagnosis of cervical glandular lesions for increased diagnostic accuracy and interobserver agreement. Most cervical glandular lesions can be differentiated by using a combination of histological scores with a panel of immunomarkers.
Modeling of Turbulent Buoyant Flows in Aircraft Cabins

Abstract Abstract—The spread of hot gases and smoke in an aircraft cabin with and without seats due to a fire located inside the cabin is simulated by a two-dimensional finite-difference field model. Results of calculations based on several scenarios of fire locations and seating configurations show signi- ficant variations in the movement of hot gases and smoke as well as in the temperature and smoke concentration levels in the seating areas.
Repair of radiation-induced chromatid aberrations: relationship to G2 arrest in CHO cells.

SummaryThe literature suggests that the function of radiation-induced G2 arrest is to allow repair of potentially lethal damage before cell-entry into, and damage expression in, mitosis. The nature of the damage repaired is not known, but chromosome aberrations have been considered. To examine this possibility in G2 cells, the rate of repair of chromatid aberrations in CHO cells progressing to or arrested in G2 was compared with the rate of repair of the damage which gives rise to G2 arrest. To measure aberration repair rates, exponentially growing CHO cells arrested in G2 with 1·5, 2·5 or 3·5 Gy of X-rays were released into mitosis by treatment with 5 mm caffeine immediately or 1, 2 or 3 h after irradiation. Aberration frequencies in these cells were then related to the caffeine-free (repair) interval. To measure the rate of repair of arrest-causing damage a split-dose procedure was used. The half-times for aberration repair were approximately 1 h for achromatic gaps and 1·5 h for breaks, intrachanges an...
Performance specification for control tower display systems

Personnel in airport control towers monitor and direct the takeoff of outgoing aircraft, landing of incoming aircraft and all movements of aircraft on the ground. Although the primary source of information for the Local Controller, Assistant Local Controller and the Ground Controller is the real world viewed through the windows of the control tower, electronic displays are also used to provide situation awareness. Due to the criticality of the work to be performed by the controllers and the rather unique environment of the air traffic control tower, display hardware standards, which have been developed for general use, are not directly applicable. The Federal Aviation Administration (FAA) requested assistance of Air Force Research Laboratory Human Effectiveness Directorate in producing a document which can be adopted as a Tower Display Standard usable by display engineers, human factors practitioners and system integrators. Particular emphasis was placed on human factors issues applicable to the control tower environment and controller task demands.
Communication skills are critical for internal auditors

Purpose – To provide internal auditors with a summary of the communications skills needed for a successful professional career in internal auditing.Design/methodology/approach – A range of recently published (2000‐2004) publications, which aim to show the importance of communication skills to internal auditors, is reviewed to show internal auditors the importance of highly‐developed communication skills in almost every aspect of their activities.Findings – Internal auditors need to possess excellent communication skills in order to succeed and advance in the changing, complex international global marketplace. Auditors utilize communication skills in almost every situation they encounter. Auditors must create an image of adding value to the organization and not just being investigators. Auditors must possess strong listening and interpersonal skills. Auditors have to be careful in using certain voice reflections when working with different types of individuals at various levels within an organization. Audi...
On the use of Raman-active longitudinal acoustic modes in the study of polyethylene lamellar structures†

The first-, third-, and fifth-order low-frequency, Raman-active, longitudinal acoustical modes of the n-alkane C94H190 and different morphological forms of semicrystalline polyethylene have been obtained. An analysis of the results shows that the correction needed to obtain the extended planar-zigzag ordered sequence length is maximum for the n-alkane and very small for the polymer systems. These represent solution crystals as well as bulk-crystallized material. For the latter, samples were prepared so that the crystallite thickness is either comparable to or very much smaller than the extended chain length. An approximate method is also developed which enables the natural linewidth to be determined.
Design methodology for the molding of short-fiber thermoset composites

Abstract The thermoelastic properties of a molded component are a strong function of the fiber orientation, which in turn is governed by the mold geometry and the processing parameters. A methodology is presented to relate mold geometry and the molding parameters to the desired thermoelastic properties of a molded section. Such a methodology enables the designer to satisfy stiffness constraints by controlling the microstructure through the selection of appropriate process conditions and rheological properties of the molding compound. The fluid flow is modelled as a laminate of two Newtonian fluids, and a non-isothermal constitutive relationship for thermoset molding compounds is proposed as the dominant mechanisms governing the thickness of the surface layer of aligned fibers. As a consequence of the resulting laminated microstructure, the inplane and flexural properties are not equivalent.
On singular integrals with variable kernels

(1978). On singular integrals with variable kernels. Applicable Analysis: Vol. 7, No. 3, pp. 221-238.
Platelet-Activating Factor and Sepsis-Induced Small Intestinal Microvascular Hypoperfusion

Platelet-activating factor (PAF) and bacteremia both cause small intestinal (SI) hypoperfusion which may contribute to mucosal injury, and PAF has been postulated to mediate impaired SI microvascular blood flow during sepsis. Our previous studies demonstrate that sepsis-induced SI hypoperfusion is associated with both arteriolar and venular constriction, but the microvascular mechanisms by which PAF impairs SI blood flow are not well defined. Microcirculation studies in other tissues indicate that PAF is an arteriolar dilator, but this effect in the SI would not explain PAF-mediated hypoperfusion. We studied the effects of PAF on SI microvessels to characterize the microvascular mechanisms which mediate PAF-induced hypoperfusion. We also determined the role of PAF as a mediator of microvascular effects in the intestine during bacteremia by PAF receptor antagonism. Animals received either 10(9) live Escherichia coli IV or PAF applied topically to the SI (30, 80, and 300 nM). Arteriolar and venular diameters and red blood cell velocity (A1, V1) were measured with intravital microscopy and velocimetry. Both PAF and sepsis resulted in impaired SI blood flow (maximum decrease in blood flow -37 and 65%, respectively), but sepsis was associated with both arteriolar and venular constriction (20 and 30% diameter reduction each), whereas PAF produced only venular constriction (50% diameter reduction). Inhibition of PAF action prevented the microvascular alterations of bacteremia (blood flow unchanged, P < 0.05; venular diameter unchanged, P < 0.05), suggesting that PAF is an important mediator of these responses.
Stimulated polarization echoes with long decay times in ferromagnetic powders

Abstract Stimulated polarization echoes with decay time, T 1 , exceeding one minute at room temperature have been detected in powders of ferromagnetic materials.
PROMOTION-SENSITIVE EPIDERMAL AND MAMMARY EPITHELIAL CELLS MAINTAINED IN SUSPENSION OVER AGAROSE

The molecular basis of tumour promotion is still largely unknown. In in vitro model of tumour promotion, the promotion-sensitive cells are induced to grow under anchorage-independent conditions in the presence of promoting agent. The customary way of providing such conditions is to immobilize these cells in soft agar, but such cells cannot be readily recovered to study the induced biochemical and molecular events. In the present report, we analysed these events using JB6 mouse epidermal cells maintained in suspension in liquid medium over agarose. 12-O-Tetradecanoylphorbol-13-acetate (TPA) induced anchorage-independent synthesis of DNA in promotion-sensitive P+ (but not in promotion-resistant P-) JB6 cells and this TPA-induced synthesis of DNA positively correlated with TPA-induced formation of colonies in soft agar. The TPA-induced synthesis of DNA began on or shortly before 24 h after the introduction of TPA, peaked at about 48 h and then declined to the control levels over the next several days. All trans-retinoic acid and dexamethasone inhibited and calcitriol (1 alpha,25-dihydroxy-vitamin D3) synergistically stimulated this TPA-induced DNA synthesis. Western immunoblot analysis of cyclins (A, B1, D1 and E) and p27Kip1, a cyclin-dependent kinase inhibitor, indicated that TPA induced cyclin A and cyclin B1 expression in P+ (but not in P-) JB6 cells and this induction coincided in time with TPA-induced synthesis of DNA. TPA also strongly induced cyclin D1 expression in P+ (but not in P-) JB6 cells, but this induction started prior to the expression of cyclin A and cyclin B1. TPA did not affect the expression of either cyclin E or p27Kip1 to any significant extent. We also found that NMU38 rat mammary epithelial cells were operationally equivalent to the promotion-sensitive P+ JB6 cells, but in these cells 17 beta-oestradiol exerted a strong synergistic effect on TPA-induced synthesis of DNA. Based on these observations, we tentatively propose a sequence of molecular events which possibly lead to the anchorage-independent synthesis of DNA in these cells.
Design considerations for a VLSI microprocessor

The machine architecture and design considerations for an interrupt-driven bipolar VLSI Microprocessor are presented. The processor is designed to a complex architecture and includes an integrated channel and a flexible storage interface. Floating-point functions are optional. A 3-ns custom bipolar technology was developed for the microprocessor, resulting in a very high circuit density package. The 50-mm four-chip air-cooled microprocessor module is packaged on a printed-circuit card with associated repowering circuits and high-speed random-access memory. Important design considerations and tradeoffs associated with the development of this machine, within specific cost, performance, reliability, and schedule objectives, are discussed. Various processor design techniques are described which minimize hardware where performance is not critical. A degree of functional parallelism is utilized, as well as timing flexibility, to attain the required performance.
Effects of mesoporous silica supports and alkaline promoters on activity of Pd catalysts in CO2 hydrogenation for methanol synthesis

Abstract Nano-structured Pd catalysts with enhanced CH 3 OH synthesis activities for CO 2 hydrogenation were prepared by integrating two different effects, i.e., incorporation of uniform mesoporous support such as MCM-41 and SBA-15 leading to small Pd nanoparticles inside nano-sized pore channels, and promotion by alkali/alkaline earth metal additives. Pd supported on these mesoporous silica without any promoters exhibited only weak activities for CH 3 OH formation, while the addition of K, Mg and Ca significantly enhanced their activities. K(Ca)-promoted Pd supported on SBA-15 yielded CH 3 OH 2–5 times as much as amorphous SiO 2 -supported Pd catalysts. The formation rate of CH 3 OH over the supported Ca/Pd varied as a function of average pore diameter of the support, and decreased in the order of MCM-41 > SBA-15 > MCM-48 > MSU-F ∼ amorphous SiO 2 . In situ Pd K-edge EXAFS and H 2 chemisorption measurements of the reduced catalysts demonstrated that small mesopores of MCM-41 and SBA-15 worked as a template for the formation of small Pd 0 nanoparticles, leading to the higher activities for CH 3 OH formation compared to the conventional amorphous silica supported counterpart.
Mutagenic consequences of the incorporation of 6-thioguanine into DNA

Abstract 6-Thioguanine (S 6 G) has been used in the treatment of acute leukemias because of its cytotoxic effect on proliferating leukemic cells. The cytotoxicity of S 6 G is thought to derive from its incorporation into DNA in place of guanine. The deoxyribonucleoside triphosphate of S 6 G, SdGTP, is a good substrate for bacterial and human DNA polymerases (Ling et al. , Mol Pharmacol 40: 508–514, 1991). Since SdGTP was observed to misincorporate in place of adenine at a greater frequency than did dGTP, it appeared plausible that this analog could produce more subtle effects (mutations) due to mispairing with thymine. To assess whether such mutations occur, SdGTP was incorporated into the lacI gene of phage M131acISaXb in reactions that omitted dGTP ( −G) or dATP (−A). LacI mutation frequency was determined by β-galactosidase colorimetric staining (inactivation of the lac repressor results in blue plaques in the absence of inducet). When a high concentration of SdGTP (24 μM) was used in the DNA polymerase reaction, phage infectivity was inhibited. When a relatively low concentration (2.4 nM) was added to the −G and −A reactions, mutagenic effects were observed. DNA sequencing of mutant progeny arising from the −G + S 6 G reaction revealed C-to-T base transitions and some C-to-A transversions. Similarly, the presence of SdGTP in the −A reactions led to mutants with T-to-C transitions. No insertions or deletions were observed. These data indicate that mispairing of S 6 G with thymine leads to mutagenic effects in this assay.
Evaluation of the carcinogenic potential of 2,4-dinitrofluorobenzene and its implications regarding mutagenicity testing

Tumor promoters are compounds which dramatically enhance the appearance of tumors when chronically applied after an initiating dose of a carcinogen. Initiators are generally considered mutagens while promoters have previously been shown not to induce either DNA damage or mutations. 2,4-Dinitrofluorobenzene (2,4-DNFB), a compound used in the identification of N-terminal amino acids of polypeptides, had been previously reported to be a tumor promoter in mouse skin, while other investigators have found it to be a mutagen in bacteria and yeast. To investigate this apparent discrepancy, we chose to study the carcinogenic potential of 2,4-DNFB utilizing various methods available in V79 Chinese hamster cells. 2,4-DNFB exposure did not result in any unscheduled DNA synthesis a measure of DNA excision repair, nor did it increase the frequency of sister chromatid exchanges in V79 cells either in the presence or absence of rat liver postmitochondrial supernatant (S-15). Forward mutations in V79 cells, either to ouabain or 6-thioguanine resistance, were not induced by 2,4-DNFB, in the presence or absence of S-15. 2,4-DNFB was, however, able to induce reversions in methionine-requiring E. coli auxotrophs in a dose-dependent fashion. Phylogenetic differences between lower organisms and mammals may account for this discordance. 2,4-DNFB was found to inhibit metabolic cooperation, in a dose dependent manner, in V79 cells. This property has previously been shown to be correlated with tumor promoting ability in mouse skin. Therefore, we conclude that the carcinogenic potential of 2,4-DNFB might reside in its ability as a tumor promoter and not as a carcinogenic initiator. Furthermore, these studies serve to illustrate the need for caution when extrapolating bacterial data for risk assessment in humans.
Magnetic coupling in dinuclear Gd complexes

A spin density functional (SDFT) study of carboxylate-bridged and diazenido-bridged dinuclear gadolinium compounds is presented. Calculated magnetic coupling constants for the carboxylate-bridged structures are in good agreement with experimental data, confirming the ability of the broken symmetry approach used in this work to predict magnetic behavior in such compounds. The systematic trend wherein symmetrically bridged complexes are antiferromagnetically coupled and asymmetrically bridged are ferromagnetically coupled is reproduced by the SDFT calculations. The mechanism underlying magnetic coupling in closed- and open-shell dinuclear complexes is described using a perturbative molecular orbital model that focuses the influence of the 4f 7-5d exchange interaction on molecular orbitals with significant 5d-orbital character for the complex [{[(Me3Si)2N]2(thf)Gd}2(N2)]. Open-shell electronic configurations facilitate strong ferromagnetic coupling, whereas in closed-shell systems antiferromagnetic coupling ...
Spin Cast Self-assembled Monolayer Field Effect Transistors

Abstract Top-contact self-assembled monolayer field-effect transistors (SAMFETs) were fabricated through both spin-coating and solution assembly of a semiconducting phosphonic acid-based molecule (11-(5⁗-butyl-[2,2′;5′,2″;5″,2‴;5‴,2⁗]quinquethiophen-5-yl)undecylphosphonic acid) (BQT-PA). The field-effect mobilities of both spin-cast and solution assembled SAMFETs were 1.1–8.0 × 10 −6 cm 2 V −1 s −1 for a wide range of channel lengths (between 12 and 80 μm). The molecular monolayers were characterized by atomic force microscopy (AFM), attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. It was found that the BQT-PA monolayer films exhibit dense surface coverage, bidentate binding, and tilt angles of ∼32° and ∼44° for the thiophene rings and alkyl chain, respectively. These results indicate that rapid throughput of fabricating SAMFETs is possible even by spin-coating.
Colorimetric determination of some sulfonamides with 9‐chloroacridine

A colorimetric procedure based on the reaction between 9-chloroacridine and primary aromatic amines has been applied to some sulfonamides and sulfonamide mixtures. It has been found to be comparable in sensitivity to other sulfonamide determinations, particularly the popular diazotization-coupling procedures. Quantitative data from several systems reveal that use of this procedure permits the determination of sulfonamides in the presence of an azo dye, tetracycline hydrochloride, sodium penicillin G, hexamethyleneamine, and other sulfonamides. Comparative analyses were performed with the method of Bratton and Marshall on sulfamerazine, sulfamethoxypyridazine, and succinylsulfathiazole tablets.
"Applejack" concentration of urinary chlorpromazine metabolites: a widely applicable and mild procedure.

Abstract Urine specimens from patients on chlorpromazine therapy, frozen in batches from 750 to 4000 ml, were slowly thawed at refrigerator temperatures of 5–8° C. Aliquots of increasing volumes were collected sequentially for determinations of comjugated and unconjugated drug fractions. From 9 to 15 fold concentration of the drug content was obtained in the initial 1 2 % of collected volumes, and from 50 to 60% of the drug metabolites were recovered in 10 to 12% of the original volumes. The procedure therefore lends itself to a variety of purposes concerned with concentration and isolation of chlorpromazine drug metabolites.
Localization of Mycobacterium leprae to Endothelial Cells of Epineurial and Perineurial Blood Vessels and Lymphatics

Infection of peripheral nerve by Mycobacterium leprae, the histopathological hallmark of leprosy, is a major factor in this disease, but the route and mechanisms by which bacilli localize to peripheral nerve are unknown. Experimentally infected armadillos have recently been recognized as a model of lepromatous neuritis; the major site of early accumulation of M. leprae is epineurial. To determine the epineurial cells involved, 1-cm segments of 44 nerves from armadillos were screened for acid-fast bacilli and thin sections were examined ultrastructurally. Of 596 blocks containing nerve, 36% contained acid-fast bacilli. Overall, M. leprae were found in endothelial cells in 40% of epineurial blood vessels and 75% of lymphatics, and in 25% of vessels intraneurally. Comparison of epineurial and endoneurial findings suggested that colonization of epineurial vessels preceded endoneurial infection. Such colonization of epineurial nutrient vessels may greatly increase the risk of endoneurial M. leprae bacteremia, and also enhance the risk of ischemia following even mild increases in inflammation or mechanical stress. These findings also raise the possibility that early, specific mechanisms in the localization of M. leprae to peripheral nerve may involve adhesion events between M. leprae (or M. leprae-parasitized macrophages) and the endothelial cells of the vasa nervorum.
On Goffman's frame analysis

Though betraying traces of the Hauptwerk-prolonged gestation period, wideranging secondary references from linguistics to theatrical history, a voluminous file of clippings poured in pell-mell-Frame A nalysis may also be regarded as yet another version, albeit a vastly distended one, of that peculiar monographic form which is Goffman's invention and to which we return below. It is in any case further testimony to the increasing rapprochement between ethnomethodology and semiotics, a development which may seem healthier for the latter, where it means liberation from a narrow dependence on linguistics, than for ethnomethodology, where, as we shall see in the present case, it suggests the spell of some distant and unattainable formalization, and is accompanied by a decided shift in emphasis from the content of social events and social phenomena to their form, from the concrete meanings of the raw material in question to the way in which they mean and ultimately to the nature of social meaning in general.
HIF-1-dependent respiratory, cardiovascular, and redox responses to chronic intermittent hypoxia.

Sleep-disordered breathing with recurrent apnea is a major cause of morbidity and mortality. Affected individuals have increased risk of systemic hypertension. Sleep apnea results in chronic intermittent hypoxia (CIH). Exposure of rodents to CIH is sufficient to induce hypertension by activation of the carotid body and sympathetic nervous system, leading to increased levels of circulating catecholamines. CIH induces increased levels of reactive oxygen species (ROS), and antioxidant treatment blocks CIH-induced hypertension. The transcriptional activator hypoxia-inducible factor 1 (HIF-1) plays an essential role in O2 homeostasis. HIF-1 activity is induced when mice or cultured cells are subjected to CIH, an effect that is blocked by antioxidants. The carotid bodies from mice that are heterozygous for a null (knockout) allele at the locus encoding HIF-1 appear histologically normal but do not respond to continuous hypoxia or CIH. In contrast to wild-type littermates, when heterozygous-null mice are subject...
Design Optimization for a Parallel MEMS Mechanism With Flexure Joints

This paper presents an analysis tool and design method for MEMS parallel mechanisms. Due to processing constraints in MEMS fabrication, flexure joints are frequently used in MEMS mechanisms. Flexure joints offer advantages over other joint designs due to their monolithic characteristics. They can be used to reduce the size of manipulators or to increase the precision of motion. Their inherent flexibility, however, also results in task space compliance which needs to be carefully designed to match the task specification. This paper presents an analysis and design tool for such mechanisms by using the differential kinematics. Performance metrics are chosen based on manipulability and task stiffness matrices, which in turn are used in a multi-objective optimization. As an illustrative example, a 1-DOF MEMS parallel mechanism based on the macro- and meso-scale models designed by NIST is considered with several choices of performance metrics and design variables. The resulting designs are successfully fabricated using DRIE process.Copyright © 2004 by ASME
Pressure–volume–temperature behavior of binary mixtures of hydrogen fluoride with HCFC-22, HFC-32 and HFC-134a

Abstract Vapor phase pressure–volume–temperature ( P – V – T ) measurements have been performed for binary mixtures of hydrogen fluoride (HF) with three different alternative refrigerants. A total of 62 mixtures were tested at temperatures ranging from 283.15 to 343.15 K. Pressures ranged from 100 to 1400 kPa, and HF concentrations varied from about 0.2 to 0.9 mole fraction HF. Several data were also obtained for the system HF/Nitrogen at 323.15 K. Data have been compared to a model based on a monomer–hexamer chemical association model and the Soave equation of state. Deviations in compressibility factors between the model and the experimental data averaged 1.5%.
Load management and automatic meter reading through the use of power line carrier

Abstract The paper shows the practicality of communications over the power line. The discussion explains the characteristics of the power line as a communication medium and a communication technique that communicates reliably in this hostile environment. The reasons for Rockwell's selection of DPSK modulation/detection are presented, and the superiority of DPSK to any other modulation/detection technique for a power line communications system is explained. It is shown that such a system is not only feasible, but that the communications reliability is more than that required to support load management and automatic meter reading. The system design presented in this paper has taken full advantage of current microprocessor technology and modern communications theory. With the microprocessor as the basic component of system elements, maximum flexibility is available to meet the evolution of requirements and lessen the probability of product obsolescence. The Rockwell communication system is capable of dealing effectively with load control, load survey, time-of-use metering, automatic meter reading and distribution automation.
Optimal Foraging in a Uniform Habitat: The Search Mechanism of the Green Lacewing

Abstract The effects of food deprivation and prey contact on the components of searching behaviour in larval green lacewings ( Chrysopa carnea Stephens) were examined to test the applicability of optimal foraging theory to predation in a uniform habitat. Variation in foraging intensity was primarily the result of changes in the meander. Modulation of the response to prey contact with increasing deprivation involved changes in the velocity and the response persistence and suggested the occurrence of adaptation to inferred differences in the spatial distribution of the prey. The ratio of giving-up times at different levels of deprivation was in accordance with the predictions of optimal foraging theory, even though the conditions precluded a discrete decision process.
Dissolution morphology of iron (oxy)(hydr)oxides exposed to the dissimilatory iron-reducing bacterium Shewanella oneidensis MR-1.

Atomic force microscopy was used to compare the dissolution morphology of iron (oxy)(hydr)oxide coated slides exposed to the dissimilatory iron reducing bacterium Shewanella oneidensis MR-1 and a Type II protein secretion mutant unable to reduce iron minerals without an exogenous electron shuttle. Dissolution morphologies of slides exposed to the wild-type organism were heterogeneous and consistent with the morphology of bacterial microcolonies observed by confocal microscopy. In contrast, dissolution morphologies of slides exposed to wild-type or mutant strains and the electron shuttling compound 9,10-anthraquinone-2,6-disulfonate were homogeneous. These results suggest that microcolony formation by the wild-type strain may limit dissolution whereas respiration using the shuttle compound relieves this limitation.
SYNTHESIS, CHARACTERIZATION AND STRUCTURAL ANALYSES OF THREE LANTHANIDE CYANIDE-BRIDGED COMPLEXES

Abstract Three lanthanide (Ln) complexes (DMF)4(H2O)3LnFe(CN)6 · H2O, where Ln = Er, Yb, and Lu, were structurally determined by means of three-dimensional single-crystal X-ray diffraction analysis. These systems crystallize in the centrosymmetric monoclinic space group P21/c (No. 14) with Z = 4 and respective lattice constants of a = 13.956(2), 13.952(1), 13.937(3); b = 8.867(4), 8.864(1), 8.862(2); c = 24.857(3), 24.812(2), 24.770(5) A; and β = 96.30(1)°, 96.33(1)°, 96.30(3)°. Final least-squares full-matrix refinements based on 3499, 3367, and 2555 unique reflections yielded reliability (R) index factors of 0.071, 0.051, and 0.032, respectively. In each complex, the coordination about the central Ln ion is eight in a square-antiprism arrangement and the coordination about the Fe ions is six, oriented octahedrally. Cyanide bridging links the Ln ions to the FeC6 groups. Molecules in the crystal lattice of each complex are held together by van der Waals forces and a network of hydrogen bonding. Characteri...
Input data resolution-induced uncertainty in watershed modelling

The temporal-spatial resolution of input data-induced uncertainty in a watershed-based water quality model, Hydrologic Simulation Program-FORTRAN (HSPF), is investigated in this study. The temporal resolution-induced uncertainty is described using the coefficient of variation (CV). The CV is found to decrease with decreasing temporal resolution and follow a log-normal relation with time interval for temperature data while it exhibits a power-law relation for rainfall data. The temporal-scale uncertainties in the temperature and rainfall data follow a general extreme value distribution and a Weibull distribution, respectively. The Nash-Sutcliffe coefficient (NSC) is employed to represent the spatial resolution induced uncertainty. The spatial resolution uncertainty in the dissolved oxygen and nitrate-nitrogen concentrations simulated using HSPF is observed to follow a general extreme value distribution and a log-normal distribution, respectively. The probability density functions (PDF) provide new insights into the effect of temporal-scale and spatial resolution of input data on uncertainties involved in watershed modelling and total maximum daily load calculations. This study exhibits non-symmetric distributions of uncertainty in water quality modelling, which simplify weather and water quality monitoring and reducing the cost involved in flow and water quality monitoring. Copyright © 2011 John Wiley & Sons, Ltd.
The phenomenon of conglomerate crystallization. XI. Clavic dissymmetry in coordination compounds. VIII. An investigation of the crystallization, conformational and configurational behaviour of [mer-Co(1,5-diamino-3-azapentane)(NO2)3]

Abstract [mer-Co(dien)(NO2)3] does not form conglomerates when crystallized from water at a variety of temperatures; instead, it crystallizes in the racemic space group Pbca. Crystals obatined at 21 °C, and studied by X-ray diffraction at 16 °C, crystallize with unit cell parameters of a = 13.030(3), b = 12.688(2) and c = 13.172(3) A; V = 2177.66 A3, D(calc; M = 300.12 g mol−1; Z = 8) = 1.831 g cm−3. Data were collected with Mo Kα (4° ⩽ 20 ⩽ 50°; 2268 data), corrected for absorption (μ = 16.01 cm−1; relative transmission coefficients range from 0.9026 to 1.0000) producing a reduced set of 1556 reflections for which I ⩾ 3σ(I). The structure was solved by the Patterson method and refined to R(F) = 0.0282 and Rw(F) = 0.0330, using as weights w = [σ(Fo)]−2. The Co(dien) fragment has the shape of pleated sheet in which the conformation of the two (NHCH2CH2NH2) fragments are δ and λ or their inverse. The two CoN(H2) distances are identical (1.942(1) and 1.944(1) A) and shorter than the CoN(H) distance of 1.952(1) A. The two mutually trans CoN(O2) bonds are 1.97(1) and 1.931(1) A, reflecting an interesting molecular asymmetry; the effect in question being the bending of one of the NO2 ligands towards the NH2CoNH2 edge of the molecule so as to maximize the strength of the bonds. The bent NO2(N4) is the one with the long CoN distance. Finally, the unique CoN(O2) distance is 1.914(1) A, shorter than either of the previous ones and a clear example of the trans effect. The geometry at Co is a distorted octahedron, as expected. The largest distortion being the angle N1CoN3(169.9(6)°) defined by the two terminalNH2 ligands. Other angular distortions are smaller. The NC distances range from 1.473(2) to 1.493(2) A and the two CC distances are 1.505(2) and 1.498(2) A. Refined NH (terminal) distances range from 0.81(2) to 0.88(2) A and the secondary NH distance is 0.90(1) A. CH distances range from 0.90(2) to 1.05(2) A.
Predictive factors, morphologic effects, and proposed treatment paradigm for type II endoleaks after repair of infrarenal abdominal aortic aneurysms.

Purpose To evaluate the predictive factors and outcome of type II endoleaks after endovascular repair of infrarenal abdominal aortic aneurysms with use of a Zenith endograft. Materials and Methods Patients classified at high risk were enrolled in a prospective study and evaluated with serial cross-sectional imaging techniques. The effect of a type II endoleak on sac behavior and associated factors were analyzed. Type II endoleaks were categorized as absent, persistent, or transient, and the morphologic effects were determined. Logistic regression and classification tree were used to predict which patients may be at risk for persistent type II endoleaks. Results A total of 273 patients were enrolled. Patients were excluded in the absence of a minimum of 6 months digital data or the presence of endoleak not classified as type II. Two hundred four patients met inclusion criteria, with a median follow-up period of 24 months (range, 6–60 months). Early type II endoleak was detected in 35 patients (17%), which resolved spontaneously in 17 cases. There were 18 patients with persistent endoleak, 17 patients with transient type II endoleak, and 169 patients with no endoleak. Aneurysm enlargement was detected in seven patients with persistent endoleak (39%), no patients with transient type II endoleak, and one patient with no endoleak. No variables were predictive of the development of persistent endoleak. The relative risk of aneurysmal growth was 77 with persistent endoleak. Successfully treated persistent endoleaks were not associated with any growth. Conclusions Persistent endoleaks are associated with sac growth. Transient type II endoleaks have a benign course and do not require treatment. Successful treatment of persistent endoleak ameliorates the risk of growth.
Cultured lymphocytes from alcoholic subjects have altered cAMP signal transduction

Previous work has shown that freshly isolated lymphocytes from alcoholic subjects show significantly reduced basal and adenosine receptor-stimulated cAMP levels. This decrease could be due to ethanol-induced cellular adaptation or to a genetic difference in the regulation of cAMP signal transduction. Therefore, we cultured human lymphocytes in defined medium without ethanol for 7-8 days and then examined differences in receptor-dependent cAMP accumulation between lymphocytes from alcoholic and nonalcoholic subjects. After four to six generations in culture without ethanol, lymphocytes from alcoholic subjects have significantly higher cAMP levels than do cells from nonalcoholic subjects. Thus, a difference in cAMP signal transduction is demonstrable in cells from alcoholic subjects grown without ethanol. We also found that cultured lymphocytes from both alcoholic and nonalcoholic subjects show a decrease in receptor-stimulated cAMP levels after exposure to 200 mM ethanol for 48 hr. To determine whether alcoholic subjects have increased sensitivity to ethanol, lymphocytes were exposed to only 100 mM ethanol for 24 hr. Under these conditions, receptor-dependent cAMP levels did not change in cells from nonalcoholic subjects. However, lymphocytes from alcoholic subjects showed a 39% decrease (P less than 0.003) in adenosine receptor-stimulated cAMP levels. Taken together, the results show that (i) chronic ethanol treatment in culture reproduces the suppression of cAMP levels found in circulating lymphocytes from alcoholic subjects and (ii) despite four to six cell divisions in culture without ethanol, lymphocytes from alcoholic subjects exhibit significantly increased adenosine receptor-dependent cAMP levels and increased sensitivity to chronic exposure to ethanol. These findings suggest that the suppression of cAMP levels observed in freshly isolated lymphocytes from alcoholic subjects results from both a direct effect of chronic exposure to ethanol and a genetic difference leading to altered cAMP signal transduction.
Effects of protein size on the rate of import of the precursors of aldehyde dehydrogenase and ornithine transcarbamylase into rat liver mitochondria.

It is known that a signal peptide is required for the import of a protein into mitochondrial matrix. It is also known that a signal peptide can be attached to any protein and allow it to be imported. We recently reported that the rate of import of rat liver mitochondrial aldehyde dehydrogenase precursor was slower than that of ornithine transcarbamylase precursor (Wang TTY, Farres J, and Weiner H. Arch Biochem Biophys 272, 440-449, 1989). It was not known if the difference in the rate of import was related to the fact that the mature portion of aldehyde dehydrogenase is larger (500 amino acids compared with 322 amino acids) or because the signal peptides were different. We further showed that treatment of the mitochondria with alcohols caused an inhibition of the import of the precursor of aldehyde dehydrogenase but not that of ornithine transcarbamylase. In the present study we constructed chimeric proteins that contained the signal peptide from one precursor protein and the mature portion from the other. We found that the rate of import was related to the overall size of the precursor protein. Consistent with this observation was finding that a truncated aldehyde dehydrogenase precursor, which contained 317 amino acids, was imported more rapidly than was the authentic precursor. Consistent with this finding was the fact that butanol caused the inhibition of only the large precursor proteins. Thus, it appears that size of the protein being imported is a major determinant of the rate at which a precursor protein is imported into mitochondria.
Piecewise-Linear Approximations of Multidimensional Functions

We develop explicit, piecewise-linear formulations of functions f(x):ℝ n ↦ℝ, n≤3, that are defined on an orthogonal grid of vertex points. If mixed-integer linear optimization problems (MILPs) involving multidimensional piecewise-linear functions can be easily and efficiently solved to global optimality, then non-analytic functions can be used as an objective or constraint function for large optimization problems. Linear interpolation between fixed gridpoints can also be used to approximate generic, nonlinear functions, allowing us to approximately solve problems using mixed-integer linear optimization methods. Toward this end, we develop two different explicit formulations of piecewise-linear functions and discuss the consequences of integrating the formulations into an optimization problem.