cssi/SciSciGPT-SciSciNet huggingface dataset:
Complex analyses of plankton structure and function.

This paper critically evaluates some complex methods that have been used to characterize the structure and function of freshwater plankton communities. The focus is on methods related to plankton size structure and carbon transfer. The specific methods reviewed are 1) size spectrum analysis, 2) size-fractionated phytoplankton productivity, 3) size-fractionated zooplankton grazing, 4) plankton ecological transfer efficiency, and 5) grazer effects on phytoplankton community structure. Taken together, these methods can provide information on community ecological properties that are directly related to practical issues including water quality and fisheries productivity. However, caution is warranted since application without a complete understanding of assumptions and context of the manipulations could lead to erroneous conclusions. As an example, experimental studies involving the addition or removal of zooplankton, especially when coupled with nutrient addition treatments, could provide information on the degree of consumer vs. resource control of phytoplankton. Resource managers subsequently could use this information in developing effective measures for controlling nuisance algal biomass. However, the experiments must be done critically and with sufficient safeguards and other measurements to ensure that treatments (e.g., zooplankton exclosure by screening of water) actually are successful and do not introduce other changes in the community (e.g., removal of large algae). In all of the methods described here, the investigator must take care when generalizing results and, in particular, carry out a sufficient number of replications to encompass both the major seasonal and spatial variation that occurs in the ecosystem.
The effects of age and feedback on isometric knee extensor force control abilities

Abstract Objective . To investigate the effects of age and feedback on submaximal isometric force control abilities in the knee extensors. Design . Analysis of a force control task in a quasi-experimental design. Background . The ability to control submaximal strength is important to accomplish activities of daily living. The purpose of this study was to investigate the effects of age, feedback, and force level on force control ability in knee extension, which is often used to accomplish daily activities. Methods . The performance of an isometric force control task was measured in young (mean age 26, SD 2.7 yrs) and older (mean age 72, SD 2.0 yrs) adult healthy male participants. Each participant maintained a steady force in knee extension at two levels of force (20% and 60% MVC) with and without visual bandwidth feedback. Age, force level, and feedback effects were examined on the dependent variables of force variability, bias, and time in bandwidth. Results . Both groups were fairly accurate at accomplishing the task, particularly at the lower force level. The higher force was harder to control, particularly when feedback was absent. The absence of feedback did not affect variability during force control. Older adults performed with less variability and a higher safety margin. Both groups performed better in time spent in bandwidth and safety margin with visual feedback, compared to the no-feedback condition. Conclusions . Healthy older and younger adults performed quite similarly regardless of feedback being provided or not. The intermittent feedback condition may have been more closely aligned with a no feedback condition rather than a continuous feedback condition. Relevance Clinical evaluation of submaximal force control ability may be useful for delineating impairments in motor skill and measuring outcomes of intervention programs. To be useful in the clinic, force control assessments must be both sensitive and specific to underlying impairments. The current study investigated the normal range of force control variability to allow the detection of true impairments.
Neurologic Examination and Extubation Outcome in the Neurocritical Care Unit

Extubation failure in the neurocritical care unit (NCCU) is difficult to predict, and is an important source of prolonged intensive care, exposure to morbidity, and increased cost. In this observational cohort study in the NCCU of a tertiary care hospital, we examined patients undergoing extubation or tracheostomy with >6 h of intubation. Observational data were collected at the time of the decision to extubate or pursue tracheostomy. The primary end-point was extubation failure within 72 h. A total of 378 tracheostomy versus extubation decisions were made on 339 individuals, resulting in 93 tracheostomies and 285 extubations. The extubation failure rate was 48/285 (16.8%). Individuals who underwent extubation had similar GCS scores [median 10T (IQR 10–11), P = 0.21]. Extubation failures had similar rates of pneumonia and fever, chest X-ray (CXR) findings, and admission diagnoses (P = NS). Factors associated with success in univariate analysis included intact gag reflex, normal eye movements, ability to close eyes to command, and ability to cough to command (all P < 0.05). In multivariate analysis, the ability to follow four commands (close eyes, show two fingers, wiggle toes, cough to command) was associated with success (P = 0.01). ROC analysis identified a significant difference in favor of a multivariate model incorporating four commands over GCS alone (P = 0.007). The ability to follow four commands and other examination criteria were strongly associated with extubation success in this observational study. Modeling suggests that specific neurologic examination parameters provide additional predictive information over GCS alone. A prospective, protocol-driven trial is needed to test and expand these findings.
The synthesis and characterization of some titanium (III) tris N,N-dialkyldithiocarbamates

Abstract It has been demonstrated that the reaction of sodium salts of dialkyldithiocarbamates with titanium trichloride in ethanol gives a yellow-green solid, which shows a three to one stoichiometry indicating a tris coordination. Infrared spectral data indicate the complexes to be approximately of D 3 h symmetry, bonded through the sulfur atoms as chelates. Magnetic data show that the d 1 state is retained.
The evolution fo rhodopsins and neurotransmitter receptors

Rhodopsins share a limited number of amino acid identities with a variety of other integral membrane proteins. Most of these proteins have seven putative transmembrane segments and are likely to play a role in transmembrane signaling. We have undertaken a systematic series of comparisons of primary and secondary structure in order to clarify the functional and evolutionary significance of these sequence similarities. On the basis of consistently high similarity scores, we find that the most internally consistent definition of the rhodopsis gene family would ionclude vertebrate rhodospins, α- and β-adrenergic receptors, M1 and M2 muscarinic acetylcholine receptors, substance K receptors and insect rhodopsins, while excluding bacterirhodopsin, themas human oncogene, vertebrate and insect nicotinic acetylcholine receptors, and the yeast STE2 and STE3 peptide receptors. The rhodopsin gene family is highly diverged at the primary sequence level but has maintained a conserved secondary structure, including a previosuly unidentified hierarchy of transmembrane segment hydrophobicity. We have deevelope new computer alogithms for progressive multiple sequence alignment and the analysis of local conservation of protein domains, and we have used these algorithms to examined the phylogeny of the rhodopsin gene family and the changing domains of sequence conservation. The results show striking diffiierences and similarities in the conserved domains in each of the three main branches of the rhodopsin gene family, and indicte that color vision arose independently in the lines of descent leading to modern humans and fruit flies.
Composite tissue allograft (CTA): tolerance induction without graft vs host disease (GvHD)

Vijay Gorantla MD, Gustavo Perez-Abadia MD, Kaustubha Prabhune MD, Haldun Orhun MD, Thanos Kakoulidis MD, Ramsey Majzoub MD, Claudio Maldonado PhD, Gary Anderson PhD, Lynn Ogden MD, Warren Breidenbach MD, Suzanne Ildstad MD, John Barker MD, PhD. Division of Plastic and Reconstructive Surgery, Institute for Cellular Therapeutics, Department of Surgery, University of Louisville & Christine M. Kleinert Institute. University of Louisville, 511 South Floyd St, 320 MDR Bldg, Louisville, KY, 40292, USA. Tel (502) 852-0166.
Tight-binding complexes of thymidylate synthetase, folate analogs and deoxyribonucleotides

Abstract Tightly-bound ternary complexes are formed when dTMP synthetase is incubated with deoxyribonucleotides such as FdUMP, dUMP, dTMP, and folate analogs, presumably mediatedy by conformational changes in the enzyme induced by these ligands. The structure of both the folate analog and the nucleotide determines the tightness of binding in the ternary complex. For example, the first order rate constant for dissociation of FdUMP from the dTMP synthetase-FdUMP PteGlu complex is almost 100-fold larger than from the dTMP synthetase-FdUMP-PteGlu3 complex. The latter had a slower rate of dissociation than did the covalent dTMP synthetast-FdUMP-5,10-CH4H4Pte-Glu complex, which had been shown to have a Kd of 10−11 M. FdUMP formed tighter complexes than did either dUMP or dTMP when using PteGlu3, PteGlu, or H2PteGlu as the folate components, but with 5,8-deazafolate complexes formed with all three nucleotides appeared to have about the same stability. H2PteGlu also induced the tight binding of dUMP to dTMP synthetase. A Scatchard plot indicated positive cooperativity in the binding of dUMP to both human and bacterial enzyme in the presence of H2PteGlu. These results suggest the possibility that when cells are exposed to MTX the decrease in dTMP synthetase activity may be due largely to formation of inhibitory enzyme-dUMP-H2PteGlun complexes and does not result primarily from depletion of reduced folates because of dihydrofolate reductase inhibition. Because this complex has a slow rate of dissociation, dTMP synthetase activity would still be inhibited for some time after an influx of reduced folates (as in leucovorin rescue) sufficient to support the enzyme reaction under normal conditions.
Olfactory Excitation of Interneurons in the Brain of the Spiny Lobster

Multimodal interneurons descending the circumesophageal connectives from the brain to the lower nervous system in decapod crustaceans respond to stimulation of cephalic sensory structures. Using intracellular recording and staining and backfilling techniques, we have examined the complexity of olfactory stimulants necessary to excite descending interneurons in the spiny lobster, and have characterized the dendritic branching pattern and responsiveness to multimodal stimulation of some of these neurons. The excitation of descending interneurons by different chemical stimulants or by different concentrations of any one stimulant appears to vary only in intensity, not in temporal pattern (Figs. 1, 2). Responses to chemical stimulation of chemoexcited interneurons at this level in the olfactory pathway resemble responses of primary receptors. Variation in the responses of chemoexcited interneurons is attributable to differences between chemical stimulants (Table 2). Two mixtures of amino acids plus betaine at concentrations proportional to their occurrence in potential foods (‘crab’ and ‘urchin’; Table 1) are more excitatory than a mixture of inverted composition or a single component, glutamic acid. Another single component, taurine, is as excitatory as equimolar ‘crab’ and ‘urchin’ mixtures. Individual chemoexcited interneurons exhibit different response spectra (Fig. 1; Tables 3, 4). Most are excited by taurine, for which there are specific antennular receptors, as well as by glutamic acid or betaine, indicating that convergence of odor qualities occurs within the olfactory pathway. Many interneurons exhibit similar concentration-response functions for taurine (Fig. 3) regardless of their responsiveness to other chemical stimulants (Table 3) or modalities (Table 4). Many chemoexcited interneurons receive bilateral chemical, tactile and visual inputs. Spatial convergence of olfactory inputs is indicated by responses of many cells to stimulation of both the ipsilateral and contralateral antennules. A few cells respond only to ipsilateral chemical stimulation. The morphological diversity of descending interneurons excited by stimulation of cephalic structures is evidenced by the variety of their dendritic branching patterns (Figs. 4–6). One striking characteristic of many chemoexcitated interneurons is the presence of extensive branching in the ipsilateral antennary neuropil (Fig. 6). Chemoexcited interneurons do not appear to contact the olfactory lobes, where the majority of the primary afferents terminate, and thus they presumably transmit at least third-order chemosensory information. Because it is unlikely that chemosensory information is further processed per se in the subesophageal nervous system, our results suggest that the chemosensory output of the spiny lobster brain is encoded by a heterogeneous population of interneurons.
The Fixed Point Theory of Multi-valued Mappings in Topological Vector Spaces.

Introduction Let K be a compact convex subset of a real topological vector space E, which we shall always assume to be separated (i.e. Hausdorff). We consider multi-valued mappings T of K into E, i.e. mappings (in the usual sense) of K into 2 e, the space of subsets of E, where for each x in K, T(x) is a non-empty closed convex subset of E. By a fixed point of such a mapping, we mean a point u of K such that u e T(u). The earliest extension of the topological theory of fixed points of continuous mappings to the case of multi-valued mappings was made by von Neumann [27] in the connection with the proof of the fundamental theorem of game theory. The extension of the Brouwer fixed point theorem to an upper semi-continuous multivalued mapping T of a n-disk into itself was carried through by Kakutani [23] and corresponding extensions of the Schauder fixed point theorem in Banach spaces were given independently by Bohnenblust-Karlin [33 and Glicksberg [193. The corresponding extension of TychonolTs theorem for locally convex topological vector spaces was proved by Ky Fan [12], who in a group of subsequent papers ([13, 14, 15, 16, 17]) refined and extended this result and considered a variety of applications. Asymptotic fixed point theorems for multi-valued mappings in Banach spaces were established in Browder [4], and parts of the Leray-Schauder theory in Banach spaces were extended to multi-valued mappings by Granas [20, 21]. It is our object in the present paper to present a new general treatment of the fixed point theory of multi-valued mappings in topological vector spaces which has the dual virtues of obtaining new and stronger results on the one hand and drastically simplifying the proofs of known results on the other. The starting point of our investigation of this theory lies in recent results of the writer in connection with the study of monotone operators and non-linear variational inequalities [6, 7, 8]. In this direction, one considers mappings S of a compact convex set K into E*, the dual space of E, rather than E itself. Instead of trying to find fixed points of a mapping T of K into E, one looks for points u in K for which S(u)= 0, or more generally, for which
Variations in Magnetic Hyperfine fields for Thin Epitaxial Heterostructures Of (110)Fe ON (111)Ag

We have made a study of magnetic heterostructures involving the epitaxial growth of (110)Fe on (111)Ag. The flatness and continuity of the films was verified by Reflection High Energy Electron Diffraction during the growth process. A series of structures were made with very thin intervening silver layers with thicker iron layers. The doping of appropriate layers by enriched Fe57 made it possible to examine the magnetic structure of the iron films as a function of depth. Preliminary results indicate that thin layers of silver sandwiched between two very thin Fe layers are able to transmit conduction electron polarization, resulting in iron behavior which resembles that of bulk iron. Implications of these results for understanding the nature of the magnetization of iron will be addressed in the following.
Three-dimensional characterization of microstructurally small fatigue-crack evolution using quantitative fractography combined with post-mortem X-ray tomography and high-energy X-ray diffraction microscopy

Abstract An experimental methodology based on post-mortem measurements is proposed to quantify rates of propagation and crack-surface crystallography of a 3-D, naturally nucleated, microstructurally small fatigue crack (MSFC) in a polycrystalline aluminum alloy (Al–Mg–Si). The post-mortem characterization involves: scanning electron microscopy-based fractography to measure crack-front projections (marker bands) at known cycle counts during the load history, X-ray computed tomography to provide high-resolution reconstructions of the 3-D crack-surface morphology, and near-field high-energy X-ray diffraction microscopy to provide 3-D grain geometries and orientations adjacent to fatigue-crack surfaces. Local MSFC-propagation rates are measured by accounting for the 3-D crack-surface morphology and varied by two orders of magnitude in the Al–Mg–Si specimen. Both intergranular and transgranular MSFC evolution were observed, with the latter occurring along a wide range of crystallographic planes. The findings demonstrate: (i) the complexity and variability of 3-D MSFC evolution in the Al–Mg–Si alloy; and (ii) the viability of the post-mortem characterization approach for quantifying 3-D MSFC evolution in polycrystalline alloys.
Fluid-induced Rotordynamic Forces and Instabilities

In the late 1970s, the authors began a collaboration with our colleague Tom Caughey that helped define a new set of fluid-structure interaction phenomena in turbomachines, namely fluid-induced rotordynamic forces and instabilities. That collaboration and the 31 joint ABC papers it produced epitomized Tom Caughey's genius and we reprise it here in his honor. The design of the space shuttle main engine (SSME) pushed beyond the boundaries of many known technologies. In particular, the rotating speeds and operating conditions of the high speed liquid oxygen and liquid hydrogen turbopumps were extreme and early testing revealed a whirl instability whose magnitude exceeded expectations and allowable limits. It was suspected and later proven that fluid-induced rotordynamic effects were a contributing factor and yet very little was known of such phenomena. As one of the efforts seeking understanding, we constructed a facility to measure fluid-induced rotordynamic forces. This was subsequently used in a broad range of investigations. Initially, the effort was directed to understanding the source and parametric variations of destabilizing fluid forces. Later various components of the flow in a high speed turbopump were investigated. And finally, some ameliorative measures and their effectiveness were examined. This paper reviews this body of knowledge and the lessons learnt along the way.
Giant anterior communicating artery aneurysm infiltrated with a primary cerebral lymphoma: case report.

Objective and importance Central nervous system lymphomas exhibit angiotropic characteristics. Nevertheless, direct association with an intracranial aneurysm is very rarely reported. We present a case of a giant aneurysm infiltrated with a large cell non-Hodgkin's lymphoma. The incidence of primary central nervous system lymphoma is increasing, and similar cases may become more frequent in the future. Clinical presentation A 65-year-old man had presented with a giant anterior cerebral artery aneurysm, new onset of seizures, aphasia, and hemiparesis. The aneurysm was treated with Guglielmi detachable coils. Six months later, the patient exhibited fever and neurological deterioration. Magnetic resonance images suggested an enhancing lesion posterior to the neck of the aneurysm. Antibiotic treatment given elsewhere was unsuccessful. Intervention A craniotomy for a suspected abscess was performed, with removal of the aneurysm and clipping of the neck. The aneurysm sac appeared to be filled with thrombus and pus. The results of aerobic, anaerobic, and fungal cultures were negative. Postoperative magnetic resonance images demonstrated a residual mass, posterior to the aneurysm within the striatum and the internal capsule. Histological examination of the aneurysm wall revealed a large B-cell lymphoma. The diagnosis was confirmed by a stereotactic biopsy. Radiation therapy resulted in a transient decrease in the size of the lesion. Conclusion Although the tumor was not apparent on the initial imaging studies, it may have been the cause of the patient's presenting symptoms. Infiltration of the aneurysm wall by the lymphoma also raises the possibility of a causal relationship. As the incidence of primary central nervous system lymphoma is reported to be on the increase, awareness this uncommon association of an aneurysm and malignant lymphoma is of value.
Absolute regularity and functions of Markov chains

Abstract We first give an extension of a theorem of Volkonskii and Rozanov characterizing the strictly stationary random sequences satisfying ‘absolute regularity’. Then a strictly stationary sequence {Xk, k = …, −1, 0, 1,…} is constructed which is a 0−1 instantaneous function of an aperiodic Markov chain with countable irreducible state space, such that n−2 var (X1 + ⋯ + Xn) approaches 0 arbitrarily slowly as n → ∞ and (X1 + ⋯ + Xn) is partially attracted to every infinitely divisible law.
Enhancement of in situ adsorption on the acetone-butanol fermentation by Clostridium acetobutylicum

Abstract An integrated process of the acetone-butanol batch fermentation coupled with in situ toxic products removal was developed. It was found that the in situ adsorption process using polyvinylpyridine as the adsorbent enhanced the fermentation rates and the reactor productivity by Clostridium acetobutylicum. In a typical traditional acetone-butanol fermentation process, only about 60.0 g/L of glucose could be used in a batch operation mode and thus at maximum only 21 g/L of the total final products concentration could be achieved. In the adsorption-coupled system, an initial glucose concentration of 94.0 g/L was fermented when a weight ratio of the adsorbent to the fermentation broth of 3/10 was used. An overall product concentration of 29.8 g/L and a productivity of 0.92 g/L · h were achieved in the adsorptive batch fermentation system. Compared with the controlled traditional batch acetone-butanol fermentation, the integrated process increased the final product concentration by 54% and the productivity by 130%.
Column sizing design aid

Presented in this paper is an interactive computer program which will aid the engineer in selecting the trial section properties of a column for the iterative design and analysis process. An algorithm is developed around the effective length factor (K) and the end restraint factor (ψ) for an unbraced frame. The output is a table of values of the ratio of the column moment of inertia to the beam moment of inertia (IR) as a function of the effective length factor (K). The program is written in standard Fortran.
Role of c-Cbl carboxyl terminus in serotonin 5-HT2A receptor recycling and resensitization

The 5-hydroxytryptamine 2A receptor (5-HT2AR) undergoes constitutive and agonist-dependent internalization. Despite many advances in our understanding of G protein-coupled receptor trafficking, the exact mechanism of endocytic sorting of G protein-coupled receptors remains obscure. Recently, we have reported a novel finding documenting a global role for the ubiquitin ligase c-Cbl in regulating vesicular sorting of epidermal growth factor receptor (Baldys, A., Gooz, M., Morinelli, T. A., Lee, M. H., Raymond, J. R., Jr., Luttrell, L. M., and Raymond, J. R., Sr. (2009) Biochemistry 48, 1462–1473). Thus, we tested the hypothesis that c-Cbl might play a role in 5-HT2AR recycling. In this study, we demonstrated an association of 5-HT2AR with c-Cbl. Furthermore, down-regulation of c-Cbl by RNA interference blocked efficient recycling of 5-HT2AR to the plasma membrane. Immunofluorescence microscopy revealed that 5-HT2A receptors were trapped in early endosome antigen 1- and Rab11-positive sorting endosomes in cells overexpressing c-Cbl mutants lacking carboxyl termini. This inhibitory effect was associated with a relative decrease in association of c-Cbl truncation proteins with the 5-HT2AR, compared with that observed for the full-length c-Cbl fusion protein. Consistent with the delayed recycling, 5-HT2AR resensitization was greatly attenuated in the presence of c-Cbl mutants lacking carboxyl termini, as detected by changes in the cytosolic calcium. Taken together, these studies have led to the discovery that the C-terminal region of c-Cbl plays a crucial role in the temporal and spatial control of 5-HT2AR recycling.
Sources of resistance to aflatoxin production in maize.

Drought-tolerant maize genotypes (Huffman, Z08-004, Tuxpan, PH 9, NRC 5348, Chunco, Saint Croix, and Arizona) were compared in the field and laboratory to toxin-resistant GT-MAS:gk and Yellow Creole. SDS-PAGE, scanning electron microscopy of kernel cuticle, amount of kernel wax, Aspergillus flavus kernel colonization, Aspergillus ear rot, insect damage, aflatoxin production, and their relationships were examined. SDS-PAGE showed the presence of a 14 kDa trypsin inhibitor in the kernels of all genotypes except Chunco, which contains a protein of a larger molecular weight. The 14 kDa trypsin inhibitor protein content in these genotypes was higher than in GT-MAS:gk and Yellow Creole. Scanning electron microscopy revealed that Arizona, Huffman, and Chunco genotypes had abundant wax deposits on kernel surfaces and the amount of pericarp wax was equal to or above that from GT-MAS:gk and Yellow Creole. Differences in Aspergillus ear rot ratings, fungal colonization, and insect damage by corn earworm were observe...
Insulin-stimulated translocation of glucose transporter (GLUT) 12 parallels that of GLUT4 in normal muscle.

Context: GLUT4 is the predominant glucose transporter isoform expressed in fat and muscle. In GLUT4 null mice, insulin-stimulated glucose uptake into muscle was diminished but not eliminated, suggesting that another insulin-sensitive system was present. Objective: This study was intended to determine whether insulin caused GLUT12 translocation in muscle. Design: Six normal volunteers had muscle biopsies before and after euglycemic insulin infusions. Setting: Infusions and biopsies were performed in an outpatient clinic. Participants: Subjects were nonobese, young adults with no family history of diabetes. Main Outcome Measures: GLUT12, GLUT4, and GLUT1 proteins were quantified in muscle biopsy fractions. Cultured myoblasts were used to determine whether GLUT12 translocation was phosphatidyl inositol-3 kinase (PI3-K)-dependent. Intervention. Insulin was infused at 40 mU/m2 · min for 3 h. Results: In human muscle, insulin caused a shift of a portion of GLUT12 from intracellular low-density microsomes to the plasma membrane (PM) fraction (17% in PM at baseline, 38% in PM after insulin). Insulin increased GLUT4 in PM from 13 to 42%. GLUT1 was predominantly in the PM fractions at baseline and did not change significantly after insulin. L6 myoblasts in culture also expressed and translocated GLUT12 in response to insulin, but inhibiting PI3-K prevented the translocation of GLUT12 and GLUT4. Conclusions: Insulin causes GLUT12 to translocate from an intracellular location to the plasma membrane in normal human skeletal muscle. Translocation of GLUT12 in cultured myoblasts was dependent on activation of PI3-K. GLUT12 may have evolutionarily preceded GLUT4 and now provides redundancy to the dominant GLUT4 system in muscle.
A Cognitive-Behavioral Treatment Program for Posttraumatic Stress Disorder in Persons with Severe Mental Illness

Clients with severe mental illnesses (SMI) such as schizophrenia and bipolar disorder have high rates of exposure to trauma over their lives, and are at sharply increased risk for the development of posttraumatic stress disorder (PTSD). However, at present there are no validated treatments of PTSD in the SMI population. In this article we describe a new cognitive-behavioral treatment program for PTSD in clients with SMI. We begin with a brief review of the research on trauma and PTSD in clients with SMI. Next, we summarize findings on the treatment of PTSD in the general population, followed by considerations in the development of a treatment program for clients with SMI. We then describe our program, which is based primarily on the principles of cognitive restructuring and involves treatment closely integrated with the ongoing provision of comprehensive services for the SMI. We conclude with a description of how common challenges of working with clients with SMI are handled in the treatment program, incl...
Synthesis of optically active imidazopyridinium salts and the corresponding NHCs

Abstract A convergent synthesis of chiral imidazo-[1,5-a]-pyridinium salts is described by facile introduction of a stereogenic center via the N2 substituent. Conversion of these optically active salts to the corresponding N-heterocyclic carbenes (NHCs) and their trapping with sulfur followed by optical activity measurements are discussed.
Specific Headache Factors Predict Sleep Disturbances Among Youth With Migraine

Abstract Background There is a paucity of pediatric data addressing the complex relationship between primary headaches and sleep disturbances. Our study objective was to explore headache-related factors that predict sleep disturbance and to compare sleep complaints with other forms of headache-related disability among youth with migraines. Methods A prospective cohort study was conducted in patients 10-18 years old with migraine or probable migraine and without daily sleep complaints. The patients completed a 90-day internet-based headache diary. On headache days, patients rated headache intensity, answered Pediatric Migraine Disability Assessment-based questions modified for daily scoring, and reported sleep disturbances that resulted as a direct effect of proximate headaches. Results Fifty-two patients generated 4680 diary entries, 984 patients (21%) involved headaches. Headache intensity ( P = 0.009) and timing of headache onset ( P P = 0.04), recreational activities prevented ( P P r pb = 0.35; P Conclusion We conclude that specific headache factors predict sleep disturbances among youth with primary headaches.
Dimethylsulfide in a large-scale coccolithophore bloom in the Gulf of Maine

Abstract Blooms of the coccolithophore, Emiliania huxleyi , are common phenomena in the Gulf of Maine in early summer, as revealed by AVHRR imagery. It is known from laboratory cultures and some field studies that the production of the important volatile sulfur compound, DMS, and its precursor, DMSP, are confined largely to a few classes of phytoplankton, specifically the Dinophyceae and the Prymnesiophyceae, which includes the coccolithophores. In the Gulf of Maine, concentrations of DMS and DMSP were as much as an order of magnitude higher within a E. huxleyi bloom than at stations outside the bloom area, including stations with high phytoplankton biomass of other taxa. Values of both DMS and DMSP were highest in the mixed layer, with depth maxima associated with the chlorophyll maxima, generally at 10–15 m. In addition, higher levels of DMS and dissolved DMSP were associated with older parts of the bloom, as determined by numbers of loose coccoliths. This is the first example in nature where DMS production is related, not only to a given species of algae, but also to the stage of the bloom.
How Pegylation Stabilizes a Protein

Protein PEGylation has been widely applied by the pharmaceutical industry for making protein drugs with lower immunogenicity, longer circulatory half-life and better bioactivity. However, the efficacy of PEGylation depends on parameters such as attachment site and chain length. Characterizing the relationship between PEGylation pattern and protein stability would therefore be beneficial to designing improved protein PEGylation. Although recent studies have shown that site-specific PEGylation has impact on protein conformation stability and folding rate, there is no clear consensus on how PEGylation stabilizes a protein on the atomistic scale.Through all-atom molecular dynamics simulation, we explored the interaction between the attached PEG oligomer and a β-sheet protein WW domain. While experiments showed clues that stabilizing effect could be attributed to specific interactions between PEG and protein surface residues, a direct correlation cannot be drawn from simulation results. The attached PEG oligomer was flexible and undergoes rapid transitions between extending into the solvent and collapsing onto the protein surface, on a 10 ns time scale. A mechanism including water mediated interaction is therefore suggested.
DIFFERENTIAL ROTATION OF SOLAR FILAMENTS

The latitudinal component of solar differential rotation and the possibility of a radial component are discussed and compared to the observed rotational velocities of solar filaments. The author's values of rotational rate versus heliographic latitude for 100 points in the solar atmosphere derived from 17 quiescent filaments are shown to be comparable to the rates found by d'Azambuja and d'Azambuja (1948). The filament rate is significantly greater than the spot rate (Newton and Nunn, 1951); the difference cannot be accounted for by the poleward migration of filaments and seems to reflect a true radial gradient of rotational velocity in the sun. It is shown that filaments in closer proximity to active regions usually exhibit no differential rotation, while those far from active regions generally show it clearly. Comparison with Mt. Wilson photospheric Doppler measurements shows that filaments rotate faster than the general photosphere and that the spot rate exceeds that for the general photosphere.
Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT) is a recently developed approach to treat dilated heart failure with discoordinate contraction. Such dyssynchrony typically stems from electrical delay that then translates into mechanical delay between the septal and lateral walls. Over the past decade, many studies have examined the pathophysiology of cardiac dyssynchrony, tested the effects of cardiac resynchronization on heart function and energetics,tested the chronic efficacy of this therapy to enhance symptoms and reduce mortality, and better established which patients are most likely to benefit. This brief review discusses these topics.
GEOMETRICAL ATTENUATION FACTORS FOR DIRECTIONAL CORRELATION EXPERIMENTS.

Abstract Experimentally determined values are given for the attenuation factors due to finite solid angle in directional correlation measurements. The method is applied to cylindrical NaI(Tl) detectors and Ge(Li) detectors. Experimental determination of attenuation coefficients is especially useful in the latter case due to the uncertainty regarding the position and extent of active volume of the Ge(Li) detector. The attenuation factors for escape peaks differ from those for the full-energy peaks of the Ge(Li) detectors. Results are given for specific detectors and geometries and verified experimentally.
Surface immobilization of DNA aptamers for biosensing and protein interaction analysis

To utilize aptamers as molecular recognition agents in biosensors and biodiagnostics, it is important to develop strategies for reliable immobilization of aptamers so that they retain their biophysical characteristics and binding abilities. Here we report on quartz crystal microbalance (QCM) measurements and atomic force microscope (AFM)-based force spectroscopy studies to evaluate aptasensors fabricated by different modification strategies. Gold surfaces were modified with mixed self assembled monolayers (SAMs) of aptamer and oligoethylene glycol (OEG) thiols (HS-C(11)-(EG)(n)OH, n=3 or 6) to impart resistance to nonspecific protein adsorption. By affinity analysis, we show that short OEG thiols have less impact on aptamer accessibility than longer chain thiols. Backfilling with OEG as a step subsequent to aptamer immobilization provides greater surface coverage than using aptamer and OEG thiol to form a mixed SAM in one-step. Immunoglobulin E and vascular endothelial growth factor (VEGF) were studied as target proteins in these experiments. Binding forces obtained by these strategies are similar, demonstrating that the biophysical properties of the aptamer on the sensors are independent from the immobilization strategy. The results present mixed SAMs with aptamers and co-adsorbents as a versatile strategy for aptamer sensor platforms including ultrasensitive biosensor design.
Hermansky-Pudlak syndrome: an immunologic assessment of 15 cases.

Purpose: The Hermansky-Pudlak syndrome is an autosomal recessive disorder consisting of the triad of oculocutaneous albinism, a storage pool platelet defect, and multisystem tissue deposition of ceroid pigment. Although the underlying metabolic defect has not been identified, secondary or associated effects on the immune system are suggested by reports of an association with disorders such as pulmonary fibrosis, granulomatous colitis, lupus, and frequent bacterial infections. We evaluated a large group of patients with the Hermansky-Pudlak syndrome to assess immune competence in this condition. Patients and methods: Fifteen patients with this syndrome were studied. Control subjects included healthy volunteers in the same age range as the patients. Peripheral blood lymphocytes and neutrophils were isolated according to previously described methods. Immunofluorescent staining, flow cytometry, and cytotoxicity assays were performed. Determination of lymphocyte transformation, mixed lymphocyte response, and neutrophil function was made. Results: Immunoglobulin levels, complement, lymphocyte subsets, natural killer and lymphokine-activated cytotoxicity, mixed lymphocyte responses, and lectin-induced transformation were normal in all patients. In addition, there was no evidence for a lymphocyte proliferative response to a preparation of urinary ceroid pigment isolated from these patients. Neutrophil function, including luminol-dependent chemiluminescence, chemotaxis, and aggregation was not significantly different from control values. Conclusion: The results suggest that there is no generalized defect of peripheral blood lymphocyte or neutrophil function in the Hermansky-Pudlak syndrome. We propose that future studies should examine the possibility that associated disorders arise from a defect within the monocyte-macrophage system, perhaps secondary to ceroid accumulation.
Climate forcing by carbonaceous and sulfate aerosols

An atmospheric general circulation model is coupled to an atmospheric chemistry model to calcu- late the radiative forcing by anthropogenic sulfate and carbonaceous aerosols. The latter aerosols result from biomass burning as well as fossil fuel burning. The black carbon associated with carbonaceous aerosols is absorbant and can decrease the amount of reflected radiation at the top-of-the-atmosphere. In contrast, sulfate aerosols are reflectant and the amount of reflec- ted radiation depends nonlinearly on the relative hu- midity. We examine the importance of treating the range of optical properties associated with sulfate aero- sol at high relative humidities and find that the direct forcing by anthropogenic sulfate aerosols can decrease from !0.81 W m~2 to !0.55 Wm~2 if grid box aver- age relative humidity is not allowed to increase above 90%. The climate forcing associated with fossil fuel emissions of carbonaceous aerosols is calculated to range from #0.16 to #0.20 Wm~2, depending on how much organic carbon is associated with the black carbon from fossil fuel burning. The direct forcing of carbonaceous aerosols associated with biomass burning is calculated to range from !0.23 to !0.16 Wm~2. The pattern of forcing by carbonaceous aerosols depends on both the surface albedo and the presence of clouds. Multiple scattering associated with clouds and high surface albedos can change the forcing from negative to positive.
Topographic diversity of fungal and bacterial communities in human skin

Microbial sequencing of samples obtained from multiple skin sites in healthy human adults shows that core-body and arm sites are dominated by fungal species of the genus Malassezia, whereas foot sites show high fungal diversity, and that skin topography is associated with differential compositions of bacterial and fungal communities. As well as protecting against invasion by pathogens, our skin plays host to a varied population of microbes, some of which have important roles in human health and disease. The bacterial component of these communities is by now fairly well known, but our knowledge of the fungal members of the skin microbiota remains limited. Here Julia Segre and colleagues construct a map of the fungal species diversity at 14 different skin sites from 10 healthy adults, and compare this with the bacterial flora. They find that fungal richness varies across the body, and that bacterial and fungal communities are shaped by different factors. One finding with particular relevance to disease is that microbial communities around the feet that are commonly affected by fungal disease, such as athlete's foot, tend to be unstable. This instability may provide opportunities for harmful microbes to flourish. This finding highlights the need to develop new treatment strategies that specifically target microbial imbalances. Traditional culture-based methods have incompletely defined the microbial landscape of common recalcitrant human fungal skin diseases, including athlete’s foot and toenail infections. Skin protects humans from invasion by pathogenic microorganisms and provides a home for diverse commensal microbiota1. Bacterial genomic sequence data have generated novel hypotheses about species and community structures underlying human disorders2,3,4. However, microbial diversity is not limited to bacteria; microorganisms such as fungi also have major roles in microbial community stability, human health and disease5. Genomic methodologies to identify fungal species and communities have been limited compared with those that are available for bacteria6. Fungal evolution can be reconstructed with phylogenetic markers, including ribosomal RNA gene regions and other highly conserved genes7. Here we sequenced and analysed fungal communities of 14 skin sites in 10 healthy adults. Eleven core-body and arm sites were dominated by fungi of the genus Malassezia, with only species-level classifications revealing fungal-community composition differences between sites. By contrast, three foot sites—plantar heel, toenail and toe web—showed high fungal diversity. Concurrent analysis of bacterial and fungal communities demonstrated that physiologic attributes and topography of skin differentially shape these two microbial communities. These results provide a framework for future investigation of the contribution of interactions between pathogenic and commensal fungal and bacterial communities to the maintainenace of human health and to disease pathogenesis.
A continuous fluorimetric assay for protoporphyrinogen oxidase by monitoring porphyrin accumulation

A continuous spectrofluorimetric assay for protoporphyrinogen oxidase (PPO, EC 1.3.3.4) activity has been developed using a 96-well plate reader. Protoporphyrinogen IX, the tetrapyrrole substrate, is a colorless nonfluorescent compound. The evolution of the fluorescent tetrapyrrole product, protoporphyrin IX, was detected using a fluorescence plate reader. The apparent Km (Kapp) values for protoporphyrinogen IX were measured as 3.8+/-0.3, 3.6+/-0.5, and 1.0+/-0.1 microM for the enzymes from human, Myxococcus xanthus, and Aquifex aeolicus, respectively. The Ki for acifluorfen, a diphenylether herbicide, was measured as 0.53 microM for the human enzyme. Also, the specific activity of mouse liver mitochondrial PPO was measured as 0.043 nmol h-1/mg mitochondria, demonstrating that this technique is useful for monitoring low-enzyme activities. This method can be used to accurately measure activities as low as 0.5 nM min-1, representing a 50-fold increase in sensitivity over the currently used discontinuous assay. Furthermore, this continuous assay may be used to monitor up to 96 samples simultaneously. These obvious advantages over the discontinuous assay will be of importance for both the kinetic characterization of recombinant PPOs and the detection of low concentrations of this enzyme in biological samples.
Marital Status and Health.

In the United States, mortality rates are higher for nonmarried people than married people, and are especially high for the formerly married. To determine if morbidity and disability reveal the same differentials, age-adjusted data from the Health Interview Survey, Health Examination Survey, 1960 and 1970 Censuses of Population, and other federal health surveys are examined. The noninstitutional population is considered first: divorced and separated people have the worst health status, with highest rates of acute conditions, of chronic conditions which limit social activity, and of disabilityfor health problems. Widowed people rank second for health status, followed by single people. Married people appear healthiest, having low rates of chronic limitation and disability. Their rates of restricted activity and medical care are intermediate, but hospital stays tend to be short. Considering the institutional population, rates of residence in health institutions are highest for single people and lowest for married ones. These results are explained by marital roles and life styles which influence health, by selectivity into a marital status because of health, and by propensities to take health actions when feeling ill.
Potentialities of Electron Bombardment Ion Engines for Electric Propulsion

This paper discusses the expected performance of electron bombardment ion sources when used for electrostatic propulsion. Two particular sources, the duoplasmatron and the Penning Ion source, are examined in some detail and suggestions are made on how their performance for application with electric thrust devices could be improved. It is concluded that electron bombardment sources may offer some advantages over surface contact engines if ways can be found to significantly improve their propellant utilization.
Career Assessment with Lesbian, Gay, and Bisexual Individuals.

This article discusses key concepts in the counseling and assessment literature that can guide sound career assessment with lesbian, gay, and bisexual individuals. Sexual identity development and e...
Scheduling of toxicology protocol studies

Abstract Longitudinal large-scale toxicology studies involving groups of animals tested sequentially and in parallel over a number of weeks or months are advantageously supported by a suitably designed computer program which instantly maps out scheduled events and workloads on a daily basis. The prescribed event schedule for each animal group, which can be varied as required by the research investigators, is treated as one scale of a multielement “slide rule,” so that the start date for each group can be adjusted independently of the others. The computer program sums each kind of event by days and in total, and automatically correlates calendar dates with animal group days, study days, and compound-series days. Weekend loads are directly indicated, as are daily loads for each “event.” Direct interactive access by remote computer terminal is available for planning future schedules, short-term work schedules, and for interim revisions to schedules during testing. Substantial benefits accrue in the time required for planning tests, and in the elapsed time for testing. Research data quality is enhanced by the avoidance of excessive daily overload of support personnel and facilities, and by the ease of monitoring protocol observance.