cssi/SciSciGPT-SciSciNet huggingface dataset:
Trace Metal Interactions Affecting Soil Loading Capacities for Cadmium

The goal of this investigation was to establish a theoretically applicable model of, and develop an approach for, the direct measurement of cadmium loading capacities under laboratory conditions. Data from the literature were fitted to a model indicating a direct, linear relationship between the logarithm of the activity of Cd/sup 2 +/ in the soil solution and the logarithm of plant uptake of cadmium. These results support the model for passive absorption of cadmium by plants. It was postulated that the diffusion of Cd/sup 2 +/ from the soil-adsorbed phase to plant roots results from the electrochemical potential ..mu.. /SUB Cd/ , gradient established between soil-adsorbed Cd/sub 2//sup +/ and that in solution, which is depleted as a result of passive absorption by plants. Laboratory methods for relating the negative logarithm of the activity of Cd/sup 2 +/ in solution, pCd, to soil-adsorbed cadmium and plant-absorbed cadmium were developed, and test results for each are presented. It was concluded that this approach is theoretically valid and will provide routine laboratory methods for measuring soil loading capacities to protect the human food chain from undesirable concentrations of cadmium.
Vocational Transition in Acute Care Psychiatry

The history of vocational rehabilitation in mental health occupational therapy is a sporadic one. Today, vocational integration is an essential part of holistic practice. The Vocational Transition group protocol identifies vocational services in acute care settings for psychiatric inpatients who are planning to return to work after discharge.
Low temperature deformation and dislocation substructure of ruthenium aluminide polycrystals

Abstract The flow behavior and dislocation substructure present in ruthenium aluminide polycrystals due to deformation at room temperature and 77 K have been studied. Dislocations with three different types of Burgers vectors have been identified after 1–2% deformation in compression at 77 K and room temperature: 〈100〉, 〈110〉 and 〈111〉. The 〈100〉 and 〈110〉 dislocations are present with approximately equal densities, while the 〈111〉 are only occasionally observed. Trace analyses show that the majority of the dislocations are mixed in character and lie on {110} type planes. The implications of these observations with regard to the number of independent slip systems and the intrinsic deformability of this material are discussed.
Exciton thermodynamics in coupled quantum wells (Invited Paper)

In a single quantum well with no applied electric field, the typical exciton lifetime is subnanosecond. Excitons do not have time to reach thermodynamic quasi-equilibrium before recombining. Quasi-equilibrium requires both an average exciton kinetic energy of kT and thermalized occupation of the inhomogeneously broadened exciton density of states. In a coupled double quantum well under an electric field, lifetimes of the `indirect' excitons (i.e., electrons and holes mostly confined in different wells) are substantially longer, typically in the range 10 to 100 nsec. We have measured cw and time-resolved photoluminescence and photoluminescence excitation spectra as a function of temperature from a symmetric coupled double quantum well. The double wells consisted of 50 angstrom GaAs wells separated by a 40 angstrom Al0.3Ga0.7As barrier, and an electric field of 30 kV/cm was applied across the wells. The indirect exciton lifetime was measured to be 40 nsec for temperatures between 2 K and 30 K. Direct analysis of the data (discussed in detail in Refs. 3 and 4 shows that: (1) Below 6 K, the excitons are metastably trapped in spatial domains which are local energy minima; thermodynamic quasi-equilibrium is not achieved within the exciton lifetime. (2) Raising the temperature above 6 K increases the exciton kinetic energy and allows the excitons to be thermally activated out of these local minima; thermodynamic quasi-equilibrium is achieved. (3) The quasi-equilibrium occupation of the exciton density of states is very well approximated by a Fermi-Dirac distribution. This last observation is particularly noteworthy, in that excitons are bosons and there have been predictions of Bose-Einstein condensation in this system. Because of the electric dipole of the indirect excitons in coupled wells, there is a repulsion between the excitons. This repulsion is strong enough to cause the excitons to avoid each other, but sufficiently short ranged to be neglected for spatially separated excitons. Since the different energies in the inhomogeneously broadened density of states correspond to spatially different positions in the well, this exciton-exciton interaction can be modelled using non-interacting thermodynamic statistics but using a Fermi-Dirac distribution to approximately account for the repulsion.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Alternative pre-mRNA splicing in Drosophila spliceosomal assembly factor RNP-4F during development.

Abstract The 5′- and 3′-UTR regions in pre-mRNAs play a variety of roles in controlling eukaryotic gene expression, including translational modulation. Here we report the results of a systematic study of alternative splicing in rnp-4f, which encodes a Drosophila spliceosomal assembly factor. We show that most of the nine introns are constitutively spliced, but several patterns of alternative splicing are observed in two pre-mRNA regions including the 5′-UTR. Intron V is shown to be of recent evolutionary origin and is infrequently spliced, resulting in generation of an in-frame stop codon and a predicted truncated protein lacking a nuclear localization signal, so that alternative splicing regulates its subcellular localization. Intron 0, located in the 5′-UTR, is subject to three different splicing decisions in D. melanogaster. Northern analysis of poly(A+) mRNAs reveals two differently sized rnp-4f mRNA isoforms in this species. A switch in relative isoform abundance occurs during mid-embryo stages, when the larger isoform becomes more abundant. This isoform is shown to represent intron 0 unspliced mRNA, whereas the smaller transcript represents the product of alternative splicing. Comparative genomic analysis predicts that intron 0 is present in diverse Drosophila species. Intron 0 splicing results in loss of an evolutionarily conserved stem-loop constituting a potential cis-regulatory element at the 3′-splice site. A model is proposed for the role of this element both in 5′-UTR alternative splicing decisions and in RNP-4F translational modulation. Preliminary evidences in support of our model are discussed.
Administration of Dehydroepiandrosterone to Burned Mice Preserves Normal Immunologic Competence

• Burned individuals display a reduced ability to elicit cellular and humoral immune responses and a depression in the in vitro production of certain T-cell lymphokines. Treatment of burned mice with 100 μg of dehydroepiandrosterone within 1 hour after injury resulted in preserving a completely normal capacity to produce T-cell—derived lymphokines and to generate cellular immune responses. In addition, dehydroepiandrosterone-treated thermally injured mice demonstrated an above-normal ability to resist an induced infection with the intracellular pathogen, Listeria monocytogenes. Dehydroepiandrosterone-treated animals also did not exhibit the sustained plasma levels of interleukin 6 that normally accompany thermal injury and infection. Because of its antiglucocorticoid effects and positive immunoregulatory influences, we believe dehydroepiandrosterone to be a beneficial form of therapy for thermally injured individuals. ( Arch Surg. 1993;128:318-325)
The politics of naming: critiquing “learner-centred” and “teacher as facilitator” in English language and humanities classrooms

“Learner-centred” and “teacher as facilitator,” among the most influential concepts (re)shaping education over the past decades, are often represented as bringing democratic participation, equality, and empowerment to learners and helping transform and liberate societies. At the same time, these concepts are constructed in binary terms with “teacher-centred” and “teacher as authority” projecting the two ends as being mutually exclusive. Drawing on data collected through interviews and scholarly works from teachers teaching Humanities and Teaching English to Speakers of Other Languages (TESOL) in Asian and English-speaking Western universities, this article examines their positionings, mode, and form of critique/criticality of learner-centred education. It demonstrates in what ways equality as the starting point (Ranciere) is not embedded in how learner-centred education has largely been promoted in these contexts. As well, while Ranciere’s concepts of equality and dissensus may empower those seen as margi...
Synthesis, Crystal Structure, and Ionic Conductivity of a Polycrystalline Lithium Phosphorus Oxynitride with the γ-Li3PO4 Structure

Abstract A crystalline form of lithium phosphorus oxynitride, Li 2.88 PO 3.73 N 0.14 , has been prepared by solid state reaction between Li 3 N and LiPO 3 under a flowing N 2 atmosphere. The structure of the oxynitride was refined by Rietveld analysis of neutron powder diffraction data using the orthorhombic unit cell of γ-Li 3 PO 4 with space group Pmnb . High-performance liquid chromatography measurement indicates that most nitrogen substitutes for oxygen to form PO 3 N structural units with small concentrations of P-N[]P due to some Li ↔ P disorder in the structure. The ionic conductivity of Li 2.88 PO 3.73 N 0.14 (σ25°C ∼ 10 -13 S · cm-1) is several orders of magnitude higher than that of γ-Li 3 PO 4 (σ 25°C ∼ 10 -18 S · cm -1 ).
Characteristics of Traumatic Experience and Survivor Perceptions of Mental Health Services: The 2004–2005 Erie County Community Trauma Survey

Trauma is associated with severe mental illness and substance abuse problems, yet it typically is not addressed sufficiently in treatment. This article reports on an assessment of mental health service recipients and their experience of traumatic events and perceptions of service providers' sensitivity, helpfulness, and knowledge regarding their trauma and service needs using a community-based participatory research model. Demographic characteristics and status of co-occurring disorders were measured. Participants perceived that individual therapists and peer service providers were sensitive to and knowledgeable about their trauma. Group treatment and peer programs were seen as being most helpful. Psychiatric services were seen as being the least sensitive to trauma issues. Implications for practice and research are discussed.
Invasive Micro-optics for In Vivo Imaging in Mouse Brain

Invasive micro-optics, including both gradient index lenses and micro-prisms, enable multiphoton microscopy of deep brain structures in vivo that would otherwise be impossible to observe. We present the latest developments in use of micro-optics.
Current Options for Systemic Therapy in Mesothelioma

Systemic therapy options for patients with mesothelioma remain limited. Although many conventional chemotherapeutic agents have shown modest activity in this disease, only the combination of cisplatin plus pemetrexed has demonstrated an improvement in clinical outcomes in a phase III trial when compared with single modality therapies. Clinical investigations of the use of targeted therapies in mesothelioma are ongoing, as investigators attempt to inhibit critical pathways in this disease. This article surveys the current clinical landscape of systemic therapies in mesothelioma and explores the impact of both conventional and targeted agents.
Nitrogen fixation in the rhizosphere and rhizoplane of barley

Aerobic and anaerobic N2-fixing bacteria developed in the rhizosphere of barley seedlings and exhibited N2ase activity when seedlings were grown in sterilized sand-nutrient cultures containing low levels of combined nitrogen. The source of the N2-fixing bacteria appeared to be the seed. Average daily rates up to 0.9 μmoles C2H4 h−1 g−1 dry root tissue were measured, but the intensity of the activity was affected by moisture levels and concentration of combined N in the rhizosphere. Removal and washing of the roots did not remove the activity, and roots remained active even after surface-sterilization. An unidentified aerobic N2-fixing bacterium was isolated from the rhizoplane of active barley roots. Inoculation of barley seedlings with the aerobic N2-fixing bacterium enhanced N2ase activity of excised roots 10-fold, with average rates of 0.9, 1.1 and 1.3 μmoles h−1 g−1 dry root assayed under pO2 of 0.01, 0.02 and 0.04 atm respectively. The aerobic N2-fixing bacterium also exhibited N2ase activity when inoculated into the rhizosphere of oat, rice and wheat seedlings. Microscopic observations of sterilized live and stained barley roots suggest that the aerobic N2-fixing bacterium is an endophyte which infects root tissue and metamorphoses into vesicle-like structures.
The Completion of a Lattice Ordered Group

A lattice ordered group(‘l-group’) is called complete if each set of elements that is bounded above has a least upper bound (and dually). A complete l-group is archimedean and hence abelian, and each archimedean l-group has a completion in the sense of the following theorem.
Sorption of estrogens, triclosan, and caffeine in a sandy loam and a silt loam soil

Recently, pharmaceuticals and personal care products (PPCPs) have been identified in the environment. Concerns on the occurrence and fate of these compounds in soil and sediment have significantly increased. It is believed that these PPCPs sorb to soil and sediment; however, information on sorption of PPCPs is still limited. In this study, the sorption of estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2), triclosan, and caffeine to two loam soils and Ottawa sand was assessed. Sorption was determined using the batch equilibrium method. Freundlich and linear equations were applied to the sorption data in order to obtain sorption isotherms for each test compound and the respective sorption coefficients (K f, K d, and log K oc). The results indicated that isotherms were generally linear over the range of concentrations tested. Sorption capacity was directly related to organic carbon content such that partition coefficients for silt loam soil > sandy loam soil > sand. Triclosan had the highest values of Kf (231 in the sandy loam and 344 in the silt loam) and K d (256 in the sandy loam and 282 in the silt loam). The log Koc values for the PPCPs tested varied from 1.85 to 4.30. Desorption tests over 24 h indicated that caffeine had the greatest desorption capacity (>15%) among the compounds in sandy loam soil, while triclosan had the lowest desorption capacity ( sandy loam soil > sand.
Lactate production in blood circulating in a pump oxygenator: effect of carbon dioxide.

Abstract Blood gas tensions, pH, and glucose, lactate, and pyruvate concentrations were determined in whole blood circulated through a pump-oxygenator, ventilating the oxygenator with 100% O 2 and 93% O 2 -7% CO 2 in random order. Blood to which insulin or glucose had been added also was studied in a similar fashion. A high P O 2 was maintained throughout the study, thus eliminating any element of cellular hypoxia. Blood utilized glucose and produced lactate at a constant rate during conditions of cucapnia, and at an accelerated rate during conditions of severe hypocapnia and respiratory alkalosis. Eucapnia after hypocapnia slowed the rate of lactate production and glucose utilization but did not stop them, nor did it decrease the level of lactate in the blood. Pyruvate concentrations decreased then stabilized with hypocapnia and increased with eucapnia. Blood alone, however, seems to account for only a small fraction of the hyperlactatemia of hyperventilation in vivo . The mechanism of lactate production in blood alone with adequate oxygen levels is due to red blood cell metabolism being primarily anaerobic through the Embden-Meyerhof pathway. Whether this is accentuated by hyperoxia is not known. Also, why lactate is not decreased with hypercapnia in blood alone as occurs in vivo is not understood.
Fossil Evidence Bearing on Southwestern Mammalian Biogeography

The fossil record from the Wisconsin (Pleistocene) of Trans-Pecos Texas, New Mexico, Arizona, and southern Nevada indicates that most of the region north of a line from northwestern Arizona southeast to the Guadalupe Mountains of Trans-Pecos Texas supported habitats suitable for taxa now occurring in the high Southern Rockies of northern New Mexico and southern Colorado. South of this line, highlands were isolated from many of these taxa throughout the late Wisconsin by lowland barriers. However, many species of mammals that now occur in the Southern Rockies only in high-elevation habitats, but that occur in nonboreal habitats farther north, ranged far south of this line. Some taxa now typical of the Great Basin also occurred far to the south, some to the Mexican boundary and southeastern New Mexico. Following full­ glacial conditions, slightly warmer and more mesic summers allowed eastern and southern grass­ land taxa to penetrate westward, but with little loss of northern and Great Basin species of mammals. The full-glacial situation for lowland taxa is less well known; some had distributions similar to now, but others were restricted greatly. The present ranges of many taxa probably were reached early in the Holocene, but some taxa may have survived in refugia into the late Holocene. Several lowland taxa expanded north and west of their present ranges during the middle Holocene under conditions warmer and possibly more moist than today.
Purification, analysis, and preservation of reduced nicotinamide adenine dinucleotide 2'-phosphate.

Abstract Nicotinamide-containing cofactors are ubiquitous in biological systems. Consequently, numerous assays have been developed to study such systems that involve a variety of derivatives and isotopically labeled forms of these cofactors. Often the nicotinamide ring is labeled at the C-4 position which is directly involved in the hydride transfer chemistry catalyzed by nicotinamide-dependent enzymes. A label remote from the reactive center is often also required to follow the course of a reaction or the location of the cofactor. Since the necessary labeling pattern can be as unique as the designed experiment, these cofactors need to be synthesized, analyzed, and, most preferably, preserved. The micro-scale preservation of reduced nicotinamides has long been a challenge due to the inherent lability of the reduced cofactors. Furthermore, it has been found that the reduced 2 ′ -phosphorylated cofactor is even less stable (i.e., reduced nicotinamide adenine dinucleotide phosphate (NADPH) is more labile than reduced nicotinamide adenine dinucleotide). Presented here are methods that were established to purify nicotinamide cofactors via reverse-phase high-performance liquid chromatography (HPLC) and, most importantly, to stabilize NADPH under optimal conditions for long-term storage. Additionally, an analytical HPLC method which achieves 7-min resolution between oxidized and reduced cofactors was developed. This method also results in over 4-min resolution of these nicotinamide cofactors from various derivatives of folic acid. This analysis affords a new analytical assay for the dihydrofolate reductase-catalyzed reaction and several dehydrogenases involved in folic acid metabolism.
Cytokine inhibitors for sepsis and septic shock

Abstract Lipopolysaccharide and other bacterial products stimulate the immune cells of the host to elicit secondary inflammatory mediators, including cytokines. The 2 primary proinflammatory cytokines elicited in septic shock are tumor necrosis factor (TNF) and interleukin-1 (IL-1). Because of the importance of these cytokines in the biologic response to sepsis, they stand out as potential targets for adjunctive therapies of sepsis. This review focuses on therapies designed to inhibit the responses of TNF and IL-1, including studies in animals and humans evaluating TNF monoclonal antibodies, TNF receptor fusion proteins, IL-1 receptor antagonists, IL-1 receptor antibodies, and phosphodiesterase inhibitors. In general, the human trials have been disappointing in comparison with corresponding animal studies. As of yet, no cytokine inhibitor therapy that significantly decreases mortality in patients with severe sepsis or septic shock has been found. Copyright © 2001 by W.B. Saunders Company
Calculations of Strains and Internal Displacement Fields Using Computerized Tomography

A novel treatment of computerized tomography is developed to calculate strains and displacements at internal nodes from known boundary displacements. The formulation is blended with finite element numerical scheme. Numerical simulations are performed to verify accuracy of this new technique using several plane problems whose solutions exist in closed form. Excellent agreement shows the potential of developing the tomographic technique into a hybrid numerical-experimental method for solving mechanics problems.
The Concept of “Isolation” in Contemporary Aesthetic Theory

A consideration of the concept of “isolation” in contemporary aesthetic theory will enable me to suggest a position which denies that the aesthetic has to do only with what is immediately presented. The point will be made by arguing that a work of art exhibits aspects or elements which are tied to a historical period and that in some cases a work of art cannot be viewed aesthetically until these elements are considered or evaluated. An analysis of three uses of isolation in contemporary aesthetic theory will enable me to show the relevance of the historical components of a work of art to the aesthetic response.
Private property, public archaeology: resident communities as stakeholders in American archaeology

AbstractIn the United States, archaeological sites on private lands have few legal protections, and are thus at risk of damage or destruction. To alleviate these risks, archaeologists must engage thoughtfully with private property owners and develop strategies to promote site stewardship. In this article, I identify the resident community – those people who live on archaeological sites, regardless of their ancestral ties to those sites – as an important stakeholder in archaeology. Based on recent fieldwork experiences on a privately owned site in the south-eastern US, I discuss the unique challenges of engaging a resident community in archaeological research, and the potential of such engagement for fostering archaeological stewardship. Specifically, I use theories of place attachment derived from environmental psychology to explore how resident communities may be encouraged to empathize with and protect the archaeological records of past people.
Variability in Diagnosing Creutzfeldt–Jakob Disease Using Standard and Proposed Diagnostic Criteria

INTRODUCTION Creutzfeldt-Jakob disease (CJD) is a rapidly progressive dementia with a median survival of 2-14 months. The diagnosis can only be made accurately by biopsy/autopsy. However, this is not always feasible or desirable. Thus, diagnostic criteria have been proposed by UCSF, European MRI-CJD Consortium, and WHO. We will compare these criteria. PATIENTS AND METHODS Retrospective study of 31 patients (average age of 69.2 years) between 2003 to 2010 by ICD9 codes 046.1, 046.11, and 046.19. RESULTS All patients presented with rapidly progressive dementia (mean duration of 4.25 months). Pyramidal and extrapyramidal findings, myoclonus, cerebellar changes, akinetic mutism, and visual disturbances were observed in 6.5-48.4%. Five had periodic pattern on EEG. CSF biomarker 14-3-3 was positive in 11. Tau was positive in 6. Neuron specific enolase was positive in 9. By consensus (kappa = 0.62), MRI was “typical” of CJD in 23 with cortical ribboning (n = 16), basal ganglia hyperintensity (n = 15), or combination (n = 8). By WHO criteria, which does not include neuroimaging, CJD was diagnosed in 10, but 14 if any CSF biomarker was used (p = NS). The UCSF criteria, which does not include CSF biomarkers, diagnosed 18 cases, and the European MRI-CJD Consortium, which includes neuroimaging and CSF biomarkers but with less neurological signs, diagnosed 23 cases (p < 0.05 and p < 0.001, respectively). CJD-mimics included urosepsis, neurosarcoidosis, idiopathic left temporal lobe epilepsy, alcohol intoxication, central nervous system vasculitis, viral encephalitis, and non-Hodgkin's lymphoma. CONCLUSION This study illustrates the variability in diagnosing CJD and emphasizes the diagnostic utility of neuroimaging. It also highlights false-positives that occur with neuroimaging.
Local structure and oxide-ion motion in defective perovskites

Abstract Macroscopic thermodynamic and transport properties of disordered materials are determined largely by their local structure, which may differ substantially from long-range crystalline symmetry. In order to better understand local structure and ionic motion in highly disordered perovskite oxides, we have investigated several cubic perovskites using high-temperature oxygen-17 NMR in conjunction with other experimental techniques. Materials we have studied include Ba(In 0.67 Zr 0.33 )O y , Ba(In 0.67 Ce 0.33 ) O y , (La 0.5 Ba 0.5 ) (Co 0.7 Cu 0.3 O y , and (La 0.6 Sr 0.4 ) (Co 0.8 Cu 0.2 ) O y . We show that despite having the long-range cubic symmetry as determined by X-ray and neutron powder diffraction, these materials possess microdomains with layered structures on a short length scale (50–500 A). These microdomains are apparent in HRTEM images of these materials, and manifest themselves as unit cell doublings in the electron diffraction patterns. Neutron powder profile refinements and oxygen- 17 DAS NMR both suggest that oxygen nuclei are displaced from sites of cubic symmetry in a manner reminiscent of layered perovskite-related structures. As is the case with known layered materials, the high temperature oxygen- 17 spectra and relaxation measurements show that few oxygen atoms are mobile below 800°C due to trapping of oxygen-ion vacancies in ordered layers. In the case of (La 0.6 Sr 0.4 ) (Co 0.8 Cu 0.2 ) O y , estimates of the vacancy trapping energy and the vacancy migration energy, extracted from NMR, appear to rationalize macroscopic transport measurements.
Partnering to train group therapists

Partnerships between mental health organizations and universities are necessary to provide opportunities for graduate students to observe experienced group therapists. Both students and experienced clinicians can benefit from a training model that blends the craft knowledge and book knowledge in group psychotherapy. A description of this interorganizational training arrangement which has worked for four years is presented.
Bulbospinal projections in the primate: a light and electron microscopic study of a pain modulating system.

The projections of the nucleus raphe magnus (NRM) and the immediately adjacent reticular formation were studied in the macaque monkey following injections of the rostroventral medulla with 3H-leucine and examination of the resultant labeled axons and terminals by light and electron microscopic autoradiography. Five monkeys had accurately placed injections, which resulted in fiber pathway labeling that coursed caudally, laterally, and dorsally to project to laminae I, II, and V of subnucleus caudalis of the trigeminal and then traveled in the dorsolateral funiculus of the cord and terminated in similar laminae of the spinal dorsal horn at cervical levels. The pathway was only lightly labeled caudal to the cervical enlargement and could not be readily discerned above background in the thoracic or lumbar cord. Electron microscopy revealed that axons and terminals serving this system constitute a heterogeneous population. Large-diameter myelinated axons (3–6-μm diameter), small myelinated axons (0.75–3-μm diameter), and clusters of nonmyelinated axons were labeled. Terminals in laminae I, II, and V contained mixtures of clear round and granular vesicles or clear pleomorphic and granular vesicles or formed the central element in synaptic glomeruli. The labeled profiles formed asymmetrical or symmetrical synapses on medium and small dendrites; labeled axosomatic synapses were not observed. In rare instances there were contacts between labeled profiles and vesicle-containing structures, which were probably dendritic, but whether the NRM axon was pre- or postsynaptic to such structures could not be determined. It was concluded that the NRM in the monkey is organized in a manner quite similar to that previously described in the cat. The wide variety of fiber types and synapti termials serving this system suggests that different classes of neurons participate in it, probably using several transmitter substances that result in varying postsynaptic effects on neurons located in the trigeminal complex and dorsal horn.
Characterization of atherosclerotic lesions with laser-induced time-resolved fluorescence spectroscopy

The time-dependent decay of arterial wall fluorescence remains relatively unexplored. We measured the timeresolved fluorescence emission (337 urn excitation) of 37 excised samples of human aorta classified histologically as normal or Type I- Type Va atherosclerotic lesion (Stary's classification). Time-resolved spectra (370-510 nm, 0.5 ns temporal resolution) were constructed by deconvoluting the emission waveform using the discrete-time Laguerre basis for expansion of the decay. The spectra changed markedly with tissue type, being spectrally broad for normal samples and peaked for atherosclerotic samples. In the time dimension, the emission lasted longer for the atherosclerotic samples. Biexponential approximation of the fluorescence time-dependent decay (390 nm) showed that the long decay constant for Type II lesions (5.95±0.16 ns) was larger than the corresponding parameter for normal arterial wall (5.42±0.17 ns) and smaller than the decay constant for intermediate (Type III) and advanced (Types P1-Va) lesions (6.88±0.32 ns, 7.38±0.51 ns). Discriminant analysis using the time constants at 390 nm and the intensity ratio I 39011 470 as predictor variables classified near-normal (normal-Type I) and diseased samples (Types ffi-V) with <90% sensitivity. 75% of Type II lesions were correctly classified. These results suggest that atherosclerotic lesions can be accurately classified based on their time-resolved fluorescence spectra. Keywords: time-resolved fluorescence, atherosclerosis, nitrogen laser, arterial wall, classification of lesions
FueVAir Nonuniformity-Effect on Nitric Oxide Emissions

An analytical and experimental study was performed to determine the effect of inlet fuel/air profile nonuniformity on NO(x) emissions. The theoretical NO(x) levels were verified in a flame-tube rig at inlet air temperatures of 600, 700, and 800 K, 0.3 MPa rig pressure, 25 m/sec reference velocity, overall equivalence ratio of 0.6 and residence time near 0.002 sec. The theory predicts an increase in NO(x) emissions for increased fuel/air nonuniformity for average equivalence ratios less than 0.7, while for average equivalence ratios near stoichiometric, increasing the nonuniformity will decrease NO(x) emissions. The results can be used to predict the degree of uniformity of fuel/air profiles necessary to achieve NO(x) emissions goals for actual engines that use lean premixed, prevaporized combustion systems.
Genetic insights into the morphogenesis of inner ear hair cells

The mammalian inner ear is a sensory organ that has specialized hair cells that detect sound, as well as orientation and movement of the head. The 'hair' bundle on the apical surface of these cells is a mechanosensitive organelle that consists of precisely organized actin-filled projections known as stereocilia. Alterations in hair-bundle morphogenesis can result in hearing loss, balance defects or both. Positional cloning of genes that underlie hereditary hearing loss, coupled with the characterization of corresponding mouse models, is revealing how hair cells have adapted the molecular mechanisms of intracellular motility and intercellular adhesion for the morphogenesis of their apical surfaces.
Hormonal regulation of androgen-binding protein in the rat.

Effects of gonadotropins and gonadal steroids on androgen-binding protein (ABP) production by the testis and its secretion into the blood and transport into the epididymis were studied in 20- and 30-day-old rats. These animals had been treated with hCG, FSH, the Nal-Glu GnRH antagonist [Ac-D2Nal1,D4ClDPhe2,D3Pal3,Arg5,DGlu6(AA) ,DAla10]LHRH (antagonist), testosterone propionate, or estradiol benzoate, alone or in combination, for 10 days before assessment of ABP. Antagonist administration suppressed the testicular content (nanograms per organ) of ABP to below control (untreated) levels in both age groups. When hCG or testosterone was given along with the antagonist, they overcame the effect of the antagonist, and the resultant ABP values exceeded untreated control levels in both the 20- and 30-day-old rats. Treatment of rats with these hormones in the absence of the GnRH antagonist also elevated the ABP content of the testis above that of untreated controls. FSH administered with antagonist was able to prevent the antagonist-induced suppression of testicular ABP content. When rats were treated with FSH alone, the content of ABP in the testis was increased above untreated control levels in the 30-day-old group, but not in the 20-day-old group. The simultaneous administration of FSH and hCG did not result in an increase in testicular ABP content above that caused by hCG or testosterone alone. The increase in the ABP content of the testis caused by FSH administration was only about one sixth that caused by hCG or testosterone. Since testosterone or hCG, even in the presence of antagonist, was able to maximally stimulate ABP production by the testis of both age groups, we conclude that testosterone is the major in vivo regulator of its synthesis. Only combined treatment with hCG and FSH was able to increase transport of ABP into the epididymis of 20-day-old rats. All treatments that increased the testicular content of ABP in the 30-day-old rats also increased its transport into the epididymis. Treatments that drastically reduced the content of ABP in the testis of 20-day-old rats (antagonist, estradiol, estradiol plus antagonist) also reduced ABP secretion into the serum. Only treatment with estradiol reduced the secretion of ABP into the serum of 30-day-old rats. None of the treatments increased the ABP secretion into the bloodstream above untreated control levels.
Community development alters photosynthesis‐irradiance relations in stream periphyton

The effects of biomass accumulation and community age on the photosynthesis-irradiance response of periphyton were examined in developmental sequences from three stream locations that differed in canopy cover. (P-I) curves for four developmental stages from each location were constructed from 14C uptake at six irradiances (22–1,100 µmol quanta m‒2 s‒1) in the laboratory. Photoinhibition in the periphyton from the two shaded sites declined with development, indicating that self-shading significantly influenced photosynthesis in older communities. Photoinhibition was absent, however, in all of the developmental stages from the high light site. Maximum photosynthesis (Pmax) and slope (α) of the light-limited portion of the chlorophyll-specific light response decreased >40% in developing periphyton at all sites. Significant negative correlations between biomass and biomass-specific Pmax suggested that light or metabolic substrates became progressively more limiting during development. Although there was little community-level evidence of shade adaptation during development (photosynthesis did not saturate at lower light intensities as development proceeded), periphyton understories appear to retain considerable photosynthetic potential despite significant shading by upper layers.
The chronic toxicity of 3-chloro-4-methyl benzamine HCl to birds

3-Chloro-4-methyl benzamine HCl (DRC-1339), an avian toxicant, was fed to five species of birds for periods up to 120 days. The 30-day LC50 of uniformly treated feed for starlings was 4.7 ppm and the 90-day LC50 was 1.0 ppm. The 28-day LC50 for coturnix was 18 ppm. The 30-day LC50 for pigeons was less than 100 ppm. Pheasants fed diets containing 2% DRC-1339 baits diluted to a rate of 286 ppm of DRC-1339 died within 22 days. Bobwhite quail fed similar diets suffered some mortality at levels as low as 2.9 ppm, but most survived 10 times this dosage level for the 120-day test period. Application of the Kenaga “Index of Chronicity,” resulted in the conclusion that DRC-1339 was cumulatively toxic to birds.
Modifying electronic properties at the silicon-molecule interface using atomic tethers

Abstract The electronic properties at the semiconductor–molecule interface can be altered by changing the nature of covalent attachment. We examine the change in work function of the silicon surface after formation of Si–O–C, Si–C–C, and Si–S–C bonded alkyl monolayers and separate charge transfer and dipolar contributions. The chemical state, monolayer structure, and electronic properties of aliphatic monolayers with oxygen, carbon, and sulfur covalent linkages to the Si(1 1 1) surface were investigated with contact angle wetting, spectroscopic ellipsometry, infrared vibrational spectroscopy, X-ray photoemission spectroscopy, and ultraviolet photoemission spectroscopy. Vibrational spectra indicate aliphatic films tethered to Si with few gauche defects in agreement with hydrophobic contact angles and ellipsometric thickness measurements. Core level electronic spectra taken as a function of semiconductor doping reveal shifts in binding energy attributed to molecular bonding. Valence band spectra reveal the work function of the molecule–Si composite as a function of semiconductor doping and atomic tether. By combining valence band spectra with core level spectra, the electronic properties of the molecule–Si system can be understood. In particular, the relative contribution of charge transfer due to surface band bending and the polarization due to molecular dipoles were determined. The O, C, and S atomic tethers induce differing amounts of band bending and interface dipoles which can be utilized to engineer the electronic properties of molecule–semiconductor junctions.
Immunochemical studies on inter-species molecular hybrids of hemoglobin.

Abstract Several inter-species hybrids of hemoglobin have been produced, primarily under conditions of acid dissociation but also at alkaline pH. These hybrids have been analyzed using antisera, directed specifically toward horse, human A1, pig, chicken, and mouse hemoglobins. Unfractioned solutions of hybridized hemoglobins fix complement less effectively than the same two hemoglobins incubated separately under identical hybridizing conditions. The isolated hybrids do not fix complement with either homologous antibody at the dilutions of the serum used in the assay, but do not inhibit the homologous systems at these serum dilutions. The hybrids will, however, fix complement if serum concentrations greater than those used to measure the homologous system are used. A variety of hemoglobins from different species has been hybridized and the hybrids detected immunochemically. A mouse-human hybrid system has been analyzed in detail and the serological activities of the isolated hybrids studied quantitatively. Location of the antigenic determinants in two molecules as a result of hybrid formation decreases their serological effectiveness, probably by decreasing the antigenic determinant density. Evidence is presented which demonstrates the feasibility of the immunochemical method being utilized as a measure of hemoglobin hybridization. The possible usefulness of specific antibody in the detection and analysis of hybrid molecules that have been synthetized in vitro is discussed.
Virtual Team Leadership: A Case Study in Christian Higher Education

This study focused on virtual team leadership in Christian higher education by exploring the viability and acceptability of leadership practices defined by Malhotra, Majchrzak, and Rosen (2007). They identified six leadership practices effective leaders use to overcome the unique challenges associated with virtual teams, including: (a) establishing and maintaining trust through the use of communication technology, (b) ensuring that distributed diversity is understood and appreciated, (c) managing virtual work-life cycle (meetings), (d) monitoring team progress using technology, (e) enhancing visibility of virtual members within the team and outside in the organization, and (f) enabling individual members of the virtual team to benefit from the team. Using a case study design, a qualitative in-depth interview was conducted with an exemplary virtual team leader to explore his views of the leader's role and effectiveness within a virtual team environment in Christian higher education. Analysis of the data fo...
Darwin’s Busts and Public Evolutionary Outreach and Education

For the 1909 Darwin Centennial, the New York Academy of Sciences gave a large bronze bust of Charles Darwin to the American Museum of Natural History. Created by the well-known sculptor, William Couper, the bust was placed on its tall granite pedestal at the entrance at the newly designated exhibition hall, the Charles Darwin Hall of Invertebrate Zoology. Later that year, the American Museum ordered a bronze copy of the bust and presented it to Christ’s College, in Cambridge, England at the British Darwinian celebration. In 1935, Victor Von Hagen requested a plaster copy of the bust for a monument he was erecting on San Cristobal in the Galapagos Islands to celebrate Darwin’s arrival in the Galapagos. During 1960, the American Museum of Natural History returned the original bronze bust to the New York Academy of Science, where it is now on display at its headquarters in New York City. To celebrate the Darwin bicentennial, the National Academy of Sciences recreated the bust in a computer-generated copy for display at their Washington, DC headquarters.
Multicenter evaluation of primary care internal medicine residency training. Are practice goals met

Over the past decade primary care internal medicine residencies, combining inpatient and outpatient training, were developed with two goals: 1) to provide more appropriate training for practice and 2) to increase the number of general internists.l2 Although recent studies report that graduates from these programs choose primary care careers,3 the quality of ambulatory patient care practiced by residents in these new programs has not been documented. This study reports an assessment of the quality of outpatient care provided by 26 2nd-year primary care residents in six university-affiliated training programs. Our goal was to assess the clinical ambulatory practice of residents currently in training. Using a chart-based audit, patient
Sing the genome electric: excited cells adjust their splicing.

Those of us who study alternative splicing like to think it is the driving force behind the rapid evolution of human nature. Of course, we could be wrong, but in complexity and capability of the human species without a corresponding increase in gene number? Humans have an estimated 20,000–25,000 protein-coding genes, compared to about 19,200 for worms. Are we simply very smart worms? Our complexity is most evident (to us) in that most special of special human features, the brain. How did only 5 million years of evolution squeeze so much out of the primate genome so quickly? Perhaps it is not so much the written poem, but the reading that matters. While it is true that RNA polymerase controls what part of the genome to read and when, it is the spliceosome and its splicing factors—the machinery that removes noncoding information from nascent gene transcripts to make messenger RNA (mRNA)—that provide the interpretive pace, phraseology, emphasis, and intonation to the reading. The splicing machinery, through the process of alternative splicing, can produce different mRNAs and hence different proteins from the same gene, depending on the biological circumstances. Human genes produce on average three distinctly spliced alternative mRNAs rather than only one, and some genes have the potential to produce thousands of distinct mRNAs through alternative splicing. The view that alternative splicing adds the genetic complexity that makes us human may help us feel better about sharing most of our genes with less psychologically complex organisms. But is it true? Perhaps there is more to it than our own self-absorption. In this issue of PLoS Biology, An and Grabowski [1] and Lee et al. [2] connect the electrical activity of neurons with complex and coordinated regulation of gene expression at the level of alternative splicing.
The Gulf of Corinth floor

The Gulf of Corinth is a narrow, 65-mile-long, 470-fathom-deep trench. The canyons of the steep southern continental slope lead from major river mouths to coalescing sub-sea fans. A narrow abyssal plain underlain by turbidites occupies the deepest part of the gulf. Three telegraph cables were laid the length of the gulf and maintained for over fifty years. Two of the cables lay on the continental slope and one traversed the abyssal plain. The two cables on the continental slope were broken frequently by turbidity currents originating at the mouth of the major rivers. On the few occasions when cable repairs were made to the cable which crosses the abyssal plain, the cable was found buried.
Mutations of Tyrosine 537 in the Human Estrogen Receptor-α Selectively Alter the Receptor's Affinity for Estradiol and the Kinetics of the Interaction†

Mutation of tyrosine 537 (Y537) of the human estrogen receptor-alpha (hERalpha) produces receptors having a range of constitutive activity, which suggests that this residue modulates the conformational changes of the receptor. We investigated the effect of several mutations at this position, to phenylalanine (Y537F), to serine (Y537S), and to glutamic acid (Y537E), on the hormone-binding properties of the receptor. The affinities of the wt, the Y537F mutant, and the Y537S mutant for estradiol were similar: K(a) = 2.2 +/- 0.2, 3.9 +/- 0.5, and 2.8 +/- 0.4 nM(-1), respectively. By contrast, the affinity of the Y537E mutant for estradiol was reduced 10-fold, K(a) = 0.2 +/- 0.1 nM(-1). All proteins bound [(3)H]estradiol with a positive cooperative mechanism (n(H) = 1.7-1.9), indicating they can form dimers. The wt receptor and the Y537S and Y537E mutants exhibited biphasic dissociation kinetics, which is also indicative of dimerization. Surprisingly, the half-lives of the slow component of the wt and the Y537E mutant were indistinguishable, 118 +/- 3.4 and 122 +/- 4.5 min, respectively, even though the affinity of the Y537E mutant for hormone was reduced 10-fold. The half-life of the slow component of the Y537S mutant was reduced to 96.5 +/- 3.8 min. Molecular models were constructed and compared to identify changes in the structure that correlate with the observed effects on hormone binding. Local alterations in hydrogen bonding, the position of side chains, and the position of the peptide backbone were observed. Taken together, these results show that mutations at Y537 selectively alter the affinity and kinetics of hormone binding to the receptor, and are consistent with the idea that the estradiol-estrogen receptor interaction can follow more than one pathway.