cssi/SciSciGPT-SciSciNet huggingface dataset:
Token ring network management: Problem management

Following the tutorial ‘Token Ring Network Management’ article in the previous issue of the International Journal of Network Management, this article takes us through some more detailed Problem Management scenarios.
The η4-o-benzoquinone manganese tricarbonyl anion (o-QMTC) as an organometalloligand in the formation of M(o-QMTC)2(L-L) complexes (M = Mn, Co, Cd; L - L = bipy, phen): Generation of neutral 2-D networks containing two types of π - π stacking

The complex (η6-catechol)Mn(CO)3+ is readily deprotonated to (η4-o-benzoquinone)Mn(CO)3- (o-QMTC), which functions as an organometalloligand toward divalent metal ions by σ-bonding through the quinone oxygen atoms. The ligand o-QMTC, together with 2,2‘-bipyridine or 1,10-phenanthroline (L−L), was found to produce the stable complexes M(o-QMTC)2(L−L) (M = Mn, Co, Cd). Crystal structures of Mn(o-QMTC)2(bipy), Co(o-QMTC)2(bipy), and Cd(o-QMTC)2(phen) revealed in each case a two-dimensional supramolecular architecture consisting of π−π stacking and interdigitation of the bipy or phen ligands, as well as a pairwise π−π stacking of one of the two benzoquinone rings in each monomeric unit to generate dimeric units.
Worker Satisfaction and Work-Life Related Characteristics in the U.S. Construction Industry

While the U.S Construction industry is currently experiencing minimal shortage in craft workers, the shortages that existed prior to the current economic downturn are likely to return. Previous research argues that worker satisfaction plays an important role in retaining and attracting more workers into the construction industry. The authors previously presented a longitudinal study at the 2003 ASCE Construction Research Congress that examined construction worker characteristics related with satisfaction, including race, union status, education attainment, age, and worker preference from 1970s to 1990s. This paper extends those analyses along with investigation of work-life related characteristics (e.g. respondents' annual income and spousal employment) among U.S. construction workers from 1970s to 2000s, utilizing the General Social Survey (GSS) data. A comparison of these demographic characteristics between construction and other industries is made as well.
Molecular mechanisms of HIV-1 resistance to nucleoside and nucleotide reverse transcriptase inhibitors

The nucleoside and nucleotide reverse transcriptase inhibitors (NRTIs) were the first drugs used to treat HIV-1 infection and they remain integral components of nearly all antiretroviral regimens. However, the long-term efficacy of combination therapies that contain NRTIs is limited by the selection of drug-resistant variants of HIV-1. In general, NRTI therapy selects for viruses that have mutations in reverse transcriptase (RT). These mutations can be broadly categorized into two groups depending on their phenotypic mechanism of resistance. Mutations such as K65R, K70E, L74V, Q151M and M184V allow RT to discriminate against the NRTI triphosphate by increasing the enzyme’s selectivity for incorporation of the natural deoxynucleotide triphosphate substrate. By comparison, the thymidine analog mutations – such as M41L, D67N, K70R, L210W, T215F/Y and K219Q – augment the ability of HIV-1 RT to excise a chain-terminating NRTI monophosphate from a prematurely terminated DNA chain. A comprehensive knowledge of r...
Epineurial application of TNF elicits an acute mechanical hyperalgesia in the awake rat

Tumor necrosis factor alpha (TNF) injected into the sciatic nerve and neutralizing antibodies to its receptor injected around the nerve are respectively associated with inducing and blocking pain behavior beginning 1 to 3 days post-injection. This study examined the acute effects of TNF applied around the nerve trunk on the mechanical threshold (determined with von Frey hairs) and withdrawal latency to radiant heat. TNF (0.9 and 7.7 ng in 90 microL) injected onto the nerve via an indwelling catheter elicited a decrease in mechanical threshold. Following the low dose of TNF, no change in thermal latency was observed; after the 7.7 ng dose, thermal thresholds decreased and returned to baseline multiple times within the 3-hour observation period. Identical doses of TNF injected near, but not on the nerve, 90 ng of TNF injected on the nerve, and vehicle were without effect on either modality. These data indicate that effects of acutely administered TNF to the nerve trunk are capable of producing modality specific pain behavior. These changes may represent a first step in TNF-induced neuropathic pain.
Interpretation of VLF Resistivity Data for Ground Water Contamination Surveys

Very low frequency (VLF) military communications systems provide a primary field that can be used for shallow geophysical surveys to locate ground water contamination and vertical geologic contacts. Useful properties that can be easily obtained from the interaction of the earth and the primary field are the magnitude of the vertical secondary magnetic field, the surface impedence, and the phase angle between the electrical and magnetic horizontal components. The variations in the secondary magnetic field can be related to vertical geologic contacts, such as the edges of landfill trenches. The surface impedence yields an apparent terrain conductivity, which can be used to locate low-resistivity anomalies often associated with contaminated ground water. The phase angle gives information on vertical variations in resistivity, phase angles less than 45° indicating increasing resistivity with depth. The depth of penetration of the VLF field is about one skin depth. For a frequency of 20 kHz, the skin depth in meters is approximately equal to 3.67 where p is terrain resistivity in ohmmeters.
Hydrogen-bonding interactions in gas-phase polyether/ammonium ion complexes

Hydrogen bonds are among the most important interactions involved in selective complexation in host-guest chemistry. In this study a variety of hydrogen-bonded crown ether/ammonium ion complexes are generated in the gas phase by association reactions between an amine substrate and a polyether, one of which is initially protonated, and stabilized by many collisions in the chemical ionlzation source of a triple quadrupole mass spectrometer or in a quadrupole ion trap. The nature of the hydrogen-bonding interactions of the ion complexes are evaluated by comparison of their collision-activated dissociation spectra. After collisional activation, those complexes that are weakly bound dissociate to form intact protonated polyether molecules and/or ammonium ions by simple cleavages of the hydrogen-bond association interactions. In contrast, those complexes strongly bound by multiple hydrogen bonds dissociate not only to the protonated polyether and/or ammonium ions but also by extensive covalent bond cleavage of the protonated ether skeleton.This latter type of dissociation behavior suggests that the polyether/ammonium ion complexes may be sufficiently strongly bound that surpassing the high barrier to decomposition results in formation of internally excited polyether molecules that may then undergo subsequent fragmentation by skeletal cleavages. Moreover, complexes involving multiple hydrogen bonds may have slower dissociation kinetics, allowing competition from fast dissociation processes that have substantial energy barriers.
Foreign accent conversion in computer assisted pronunciation training

Learners of a second language practice their pronunciation by listening to and imitating utterances from native speakers. Recent research has shown that choosing a well-matched native speaker to imitate can have a positive impact on pronunciation training. Here we propose a voice-transformation technique that can be used to generate the (arguably) ideal voice to imitate: the own voice of the learner with a native accent. Our work extends previous research, which suggests that providing learners with prosodically corrected versions of their utterances can be a suitable form of feedback in computer assisted pronunciation training. Our technique provides a conversion of both prosodic and segmental characteristics by means of a pitch-synchronous decomposition of speech into glottal excitation and spectral envelope. We apply the technique to a corpus containing parallel recordings of foreign-accented and native-accented utterances, and validate the resulting accent conversions through a series of perceptual experiments. Our results indicate that the technique can reduce foreign accentedness without significantly altering the voice quality properties of the foreign speaker. Finally, we propose a pedagogical strategy for integrating accent conversion as a form of behavioral shaping in computer assisted pronunciation training.
Implantable Cardioverter‐Defibrillator: Patient Selection and Implantation Protocol

L'experience acquise lors des essais cliniques avec le defibrillateur implantable souligne l'importance d'un bilan physiopathologique precis dans la periode preoperatoire. Cette evaluation demande une documentation precise de la tachyarrythmie ventriculaire, une evaluation de la possibilite d'autres interventions eventuelles aussi bien que la consideration de l'interaction entre stimulateurs et medicamments antiarrythmiques. The experience obtained from the clinical trials with the automatic implantable cardioverter-defibrillator have reemphasized the need for a detailed pathophysiologic evaluation of the patient preoperatively. This evaluation requires careful documentation of the probable cause of the ventricular tachyarrhythmia and evaluation of other surgical needs of the patient, as well as consideration of the interactive effects of pacemakers and concurrent pharmacologic therapy post-operatively.
Smooth Markov partitions and toral automorphisms

We show that the only hyperbolic toral automorphisms f for which there exist Markov partitions with piecewise smooth boundary are those for which a power fk is linearly covered by a direct product of automorphisms of the 2-torus. Only a finite number of shapes occur in a certain natural set of cross-sections of the partition boundary. The behavior of the stratified structure of a piecewise smooth boundary under the mapping forces these shapes to be self-similar. This, together with expanding properties of the mapping, means that a piecewise smooth partition is in fact piecewise linear. Orbits of affine disks in the boundary are used to construct a basis of 2-dimensional invariant toral subgroups, and then the product decomposition of a covering follows easily.
Transformations of reconstituted high-density lipoprotein subclasses as a function of temperature or LDL concentration

The objectives of this study were to determine the structural changes in defined, reconstituted high density lipoproteins (rHDL) resulting from spontaneous phospholipid depletion in the presence or absence of low-density lipoproteins (LDL), to establish the precursor-product relationships among the rHDL particles and to assess the differences in behavior of rHDL particles containing apo A-I or apo A-II. The rHDL particles were prepared by the sodium cholate dialysis method, and were incubated in buffer at 50°C, or in buffer containing different concentrations of LDL at 37°C, for up to 24 h. The changes in the rHDL particle distributions with time were followed by non-denaturing gradient gel electrophoresis, and the rHDL were isolated at various time points for chemical analysis. We found that rHDL particles containing apo A-I or apo A-II lose phospholipid and gain cholesterol when incubated with LDL. Increasing LDL concentrations remove increasingly larger amounts of phospholipid. With phospholipid loss the apo A-I containing particles undergo major structural rearrangements that give rise to 78Aand 106Aparticles from 86Aand 94Aprecursors. The 78Aproducts appear to be the most stable, lipid-poor species. Reconstituted HDL particles prepared with apo A-II (94 and 101Ain diameter) are more resistant to structural rearrangements than the apo A-I counterparts under similar reaction conditions.
Exudation from Aphid Stylets during the Period from Dormancy to Bud break in Tilia americana (L.)

Aphid stylet exudation during the period from dormancy to bud break was studied in Tilia americana by means of detached branches brought from the woods into conditions of warmth and extended photoperiod. During physiological dormancy little exudation was obtained. Thereafter until mid-March exudation was more variable, but its onset accelerated progressively until mid-March, after which persistent exudation could be obtained from all branches within 2 days. When the buds were removed from one branch at this time, exudation persisted for only 5 days compared with 14 to 21 days for branches with buds. To account for these results it is suggested that a hormonal factor is produced by the buds which results in sieve-tube activation, that the factor is virtually absent during physiological dormancy, and thereafter requires a few weeks to become fully active. Determinations of sugar concentration, level of exudation, and bud dry weight indicated that exudation was most intense before the bud sinks were active and then rapidly falls off. It is suggested that the stylet acts as a sink competing with the natural sinks for solutes from a limited region of the stem. Other interpreta tions are also considered.
Effects of Relaxin on Neonatal Porcine Uterine Growth and Development

Abstract: Relaxin (RLX), a key reproductive hormone in pigs, stimulates uterine growth in pregnant and prepubertal gilts and in neonates 2 weeks after birth. The neonatal uterotrophic response to RLX is developmentally regulated and estrogen receptor dependent because RLX fails to increase uterine weight in the absence of estrogen receptor (ER)-α or when the ER is chemically inactivated. However, the role of RLX and insulin-like peptide-3 receptors, LGR7 and LGR8, respectively, in the neonatal uterotrophic response is unknown. Current studies focus on direct (LGR7/8-mediated) and indirect (ER-mediated) effects of RLX in the neonatal porcine uterus. Porcine LGR7 and LGR8 cDNAs were cloned and used as probes to identify uterine transcripts for LGR7 and LGR8, which increased from birth (postnatal day [PND] 0) to PND 14, a critical period for porcine uterine development. In situ hybridization showed that endometrial signals for both LGR7 and LGR8 are predominantly stromal during this period. Administration of RLX on PND 0, before onset of uterine ER expression, increased uterine luminal epithelial height (P <.05) but not uterine weight in the LGR7/8-positive uterus on PND 2. However, RLX increased both uterine weight and luminal epithelial height by PND 14 (P <.05), after overt endometrial ER expression. Aberrant ER activation between PND 0 and 14 alters the uterine organizational program and affects the function of adult porcine uterine tissues. Present data suggest that crosstalk between LGR7/8 and ER may be involved in estrogen-sensitive morphoregulatory events that are central to the development of an optimally functional adult uterus in the pig.
Sulfur oxidizers dominate carbon fixation at a biogeochemical hot spot in the dark ocean

Bacteria and archaea in the dark ocean (>200 m) comprise 0.3–1.3 billion tons of actively cycled marine carbon. Many of these microorganisms have the genetic potential to fix inorganic carbon (autotrophs) or assimilate single-carbon compounds (methylotrophs). We identified the functions of autotrophic and methylotrophic microorganisms in a vent plume at Axial Seamount, where hydrothermal activity provides a biogeochemical hot spot for carbon fixation in the dark ocean. Free-living members of the SUP05/Arctic96BD-19 clade of marine gamma-proteobacterial sulfur oxidizers (GSOs) are distributed throughout the northeastern Pacific Ocean and dominated hydrothermal plume waters at Axial Seamount. Marine GSOs expressed proteins for sulfur oxidation (adenosine phosphosulfate reductase, sox (sulfur oxidizing system), dissimilatory sulfite reductase and ATP sulfurylase), carbon fixation (ribulose-1,5-bisphosphate carboxylase oxygenase (RuBisCO)), aerobic respiration (cytochrome c oxidase) and nitrogen regulation (PII). Methylotrophs and iron oxidizers were also active in plume waters and expressed key proteins for methane oxidation and inorganic carbon fixation (particulate methane monooxygenase/methanol dehydrogenase and RuBisCO, respectively). Proteomic data suggest that free-living sulfur oxidizers and methylotrophs are among the dominant primary producers in vent plume waters in the northeastern Pacific Ocean.
Perceptions, expectations, and attitudes about communication with physicians among Chinese American and non-Hispanic white women with early stage breast cancer.

Purpose Asian Americans have consistently reported poorer communication with physicians compared with non-Hispanic Whites (NHW). This qualitative study sought to elucidate the similarities and differences in communication with physicians between Chinese and NHW breast cancer survivors.
Determination of intracellular pH using sensitive, clickable fluorescent probes.

Abstract We synthesized and evaluated a series of acidic fluorescent pH probes exhibiting robust pH dependence, high sensitivity and photostability, and excellent cell membrane permeability. Titration analyses indicated that probe 3 could increase its fluorescence intensity 800-fold between pH 8.0 and 4.1. Additionally, its p K a value is optimal for intracellular probing of acidic organelles. Fluorescent imaging of HepG2 and Hela cells further revealed that probe 3 demonstrates outstanding capacity for monitoring of intracellular [H + ] levels. The easily accessible terminal alkyne/azido function groups of these probes offer the possibility of rapidly constructing sensor molecule libraries using ‘click’ chemistry.
Protective action of a thromboxane synthetase inhibitor in preventing extension of infarct size in acute myocardial infarction.

Abstract U-63,557A, a new selective thromboxane synthetase inhibitor, was evaluated for its ability to prevent the extension of myocardial infarct size. Left coronary arteries of male Sprague-Dawley rats (230 – 270 g) were acutely ligated, producing a consistent model of myocardial infarction NO in rats analyzed 48 hours later. Left ventricular free wall (LVFW), creatine kinase (CK) activity,, and amino-nitrogen concentrations were assayed as indices of infarct size. U-63,557A was administered intravenously in two doses (4 and 8 mg/kg) with a split schedule (2 min post-ischemia and either 4 or 24 hrs later). Administration of the thromboxane synthetase inhibitor significantly reduced both myocardial CK and amino-nitrogen loss at a dose of 8 mg/kg, but it was only slightly effective at 4 mg/kg. Drug treatment significantly increased the percent LVFW spared; 27 ± 39% (vehicle) vs 43 ± 796 and 52 ± 796 (8 mg/kg). U-63,557A is an effective agent in myocardial ischemia for limiting the extension of infarct size after acute coronary artery ligation. Previous studies of other thromboxane synthetase inhibitors showed effectiveness in the early stages of MI. This study shows an effect on true infarct size 48 hours post-ligation, and suggests that inhibition of thromboxane A 2 plays an important role in the pathogenesis of ischemic damage in the myocardium.
A spatial habitat model for the marsh-breeding red-winged blackbird (Agelaius phoeniceus L.) in coastal Lake Erie wetlands

A spatial model was developed to predict the distribution of a marsh-nesting bird species, red-winged blackbird (Agelaius phoeniceus L.) in Lake Erie coastal wetlands. The study site was in two diked wetland basins in Ottawa County, Ohio, USA. Geographic Information System (GIS) was used for data handling, storage, analyzing and running the model. Nests of birds were located, and vegetation durability, vegetation height, vegetation density, water depth, open water and structural aspects of the study basins were quantified by low altitude aerial photography and extensive field work for ground truthing. Spatial variables such as distance to open water edge, distance to wetlands edge, and friction maps by spread over depth and stem density for simulating predator access to wetlands were generated using the GIS. Model variables and coefficients were determined using logistic regression. Vegetation durability, distance to open water and depth of water significantly (P < 0.01) affected the nesting outcome. Results show that the probability of a bird nesting in a location within a marsh increased with increasing vegetation durability, water depth, and with decreasing distance to open water edge. Model verification and validation indicated that the model did not show any interspecific interactions or clumping of nest sites defined by behavioral constraints. Results were in accordance with the conclusions of previous studies looking at breeding success of red-winged blackbird. This study validated the processes affecting nest site selection of red-winged blackbirds with extensive data and statistical analyses. The methodology and versatile character of the GIS-based spatial model enables adaptations to any other marsh-nesting bird species and geographic area. Data needed for the model are relatively easy to obtain and the model provides micro-habitat scale results that can be used by wetland conservationists and managers.
On n-uniform Hjelmslev planes

Abstract We define 1-uniform and strongly 1-uniform Hjelmslev planes (H-planes) to be the ordinary affine and projective planes. An n-uniform H-plane (n>1) is an H-plane whose point neighborhoods all are (n−1)-uniform affine H-planes. A strongly n-uniform H-plane (n>1) is an n-uniform projective H-plane which collapses to a strongly (n−1)-uniform H-plane upon identifying maximally connected points (points joined by t lines). All uniform projective H-planes are strongly n-uniform with n=1 or n=2. It is proved that all Desarguesian projective H-planes are strongly n-uniform. Many nice intersection properties are given for n-uniform H-planes; strongly n-uniform H-planes satisfy a strong intersection property called “property A.” It is proved that an n-uniform projective H-plane π is strongly n-uniform if and only if π satisfies property A, and also if and only if π*, the dual of π, is n-uniform.
Finite element stress analysis of the inhomogeneous carbon overcoat for rigid magnetic disks

Recent investigations of the initiation of the wear process have identified the presence of wear features that result from specific inhomogeneities in phase and properties of a wear coat. To better understand the creation and formation of wear debris, detailed analysis of the sliding contact stress field is required in studying tribological reliability of the protective overcoats. Stress calculations by the finite element method were used to study the response of solid multilayered materials under sliding contact interaction, assuming Hertzian contact conditions. Numerical results are presented for both homogeneous and inhomogeneous protective overcoats.
Large V waves in the pulmonary capillary wedge pressure tracing without mitral regurgitation: the influence of the pressure/volume relationship on the V wave size.

We have previously demonstrated that a large V wave in the pulmonary capillary wedge tracing may occur in the absence of mitral regurgitation. This study evaluates the role of left atrial and pulmonary vein compliance on such a finding. We studied 11 patients with coronary disease, without clinical or angiographic mitral regurgitation. Heart rate, pulmonary capillary wedge mean, A and V waves, V-wave slope, left ventricular and aortic pressures, cardiac output, and left atrial echo and apical phonocardiogram were recorded simultaneously. Preload was modified acutely by volume overload and by the administration of i.v. nitroglycerine. Volume administration induced a marked increase in V-wave pressure (13.0 +/- 9.6 vs. 27.0 +/- 9.6 mmHg, p less than 0.05), without producing mitral regurgitation, and without appreciable change in left atrial dimension by echo (33.0 +/- 4.9 vs. 35.5 +/- 5.2 mm, NS), or stroke volume (101.7 +/- 26.2 vs. 97.8 +/- 34.3 ml, NS). An increase was also seen in the A wave (13.6 +/- 8.9 vs. 23.3 +/- 8.5 mmHg, p less than 0.05), pulmonary capillary wedge mean pressure (9.8 +/- 7.2 vs. 20.6 +/- 7.8 mmHg, p less than 0.05), and left ventricular diastolic pressure (7.4 +/- 5.5 vs. 14.6 +/- 6.3 mmHg, p less than 0.05). All values returned to baseline after nitroglycerine. The compliance of the left atrium/pulmonary veins decreased with increasing pulmonary capillary wedge pressures. With large filling volumes, a small stroke volume brings on a large pressure change, thus explaining the finding of large V waves in patients with elevated pulmonary capillary wedge pressure and without mitral regurgitation.
Improved efficiencies of light-emitting diodes through incorporation of charge transporting components in tri-block polymers

9,9-Di-n-hexylfluorene-co-anthracene (DHF-ANT) random copolymer and triphenylamine (TPA)- and oxadiazole (OXA)-containing tri-block copolymers along with a crosslinked TPA polymer are used to fabricate single- and double-layer light emitting diodes (LEDs). In both single-layer and double-layer devices, TPA hole transporting components improve hole injection and transport, leading to improved device performance when low work function calcium (Ca) is used as the cathode, whereas OXA electron transporting components improve electron injection when high work function aluminum (Al) is used. This suggests that DHF-ANT copolymer and DHF-ANT blocks in the two tri-block polymers are hole-limited in devices with Ca cathodes, and electron-limited with Al cathodes. Furthermore, double-layer devices including a separate hole transporting crosslinked TPA layer increase device efficiencies by at least one order in magnitude over the corresponding single-layer devices, due to the improved charge injection, charge confinement and charge recombination.
The effects of position and size of drywall on the physical demands for installers

The present study utilized an integrated biomechanical modeling approach that was previously developed by the researchers to investigate the effects of position and size of drywall on the physical demands for drywall installers. If the drywall sheets were stored vertically instead of flat, it reduced the required muscle contraction forces and joint reaction forces at the low back and shoulder approximately 8% on average during drywall installation. In particular, the L4/L5 disc compression forces and the absolute values of L4/L5 anterior-posterior shear forces decreased 6.1% and 8.5%, respectively, and at the shoulder during lifting the forces of rotator cuff muscles decreased 9.8%, and the coracohumeral ligament forces decreased 12.8%. The reaction forces at both the GH (glenohumeral) and SC (sternoclavicular) joints were reduced 7.2% and 3.6%, respectively. The larger size (e.g., 4x12 and 4x16) of drywall sheets increased the physical burden for the installers tremendously and could expose them to a higher risk of musculoskeletal injuries and disorders. In some simulations the average low back lateral shear forces increased to 1675 N and 2152 N, respectively. These forces are well above the 1000 N recommended for a single lift. These results indicated that it would be physically too difficult or even impossible for one person alone to lift bigger and heavier drywall sheets. Therefore, sound engineering (e.g., lifting tables) and/or administrative (e.g., two-person team work) solutions to handling oversized drywall sheets are strongly recommended.
Applications of imaging techniques to studies of epithelial tight junctions

The intercellular junctional complex, which consists of the tight junction (TJ), adherens junction, and desmosomes, mediates cell-cell adhesion in epithelia and endothelia. The TJ forms the apical-most portion of this complex in epithelia, serving as a fence to lateral diffusion of apical and basolateral membrane components and as a semi-permeable barrier or gate to the flow of ions and solutes through the paracellular pathway. The TJ consists of a series of integral membrane and cytoplasmic plaque proteins with complex interactions. Included among the TJ proteins are the claudins, which play a major role in mediating the charge and solute selectivity of the junction. Yet, the profile of claudin and associated protein expression differs among epithelia and the function and regulation of many of the TJ proteins remain unknown. This review discusses the application of techniques to discern the function, localization, and regulation of epithelial TJs based on examples from published studies.
Resource partitioning among competing species--a coevolutionary approach.

Abstract A reasonably general theory for predicting the outcome of coevolution among interacting species is developed. It is applied to a model for resource partitioning among competing species. Current theory for resource partitioning is based on derivations of a “limiting similarity”—i.e., a limit to how similar competitors can be to one another consistent with coexistence. This theory presumes there is a mechanism, perhaps invasion and extinction, which causes competitors to attain the limiting similarity. The view taken in this paper is that partitioning is an evolutionary compromise between pressures for character displacement and disadvantages inherent in the shift to different resource types. A set of principles is offered for the evolution of the parameters in ecological models. (1) For single population models natural selection causes the parameters ultimately to assume those values which produce the highest equilibrium population size. (2) For models of interacting populations, but without interspecific frequency-dependence, natural selection causes the parameters to assume values which produce either the highest or lowest equilibrium population size for any species depending on the sign of the “feedback” in the community obtained by deleting that species. (3) For models of interacting populations with interspecific frequency dependence natural selection leads to parameter values which produce intermediate equilibrium population sizes. A function called the conditional equilibrium population size is introduced. Provided (a) the mean fitness is a maximum in each species at a stable coevolutionary equilibrium and (b) there is negative density-dependence in each species then natural selection causes the parameters to assume values which produce the highest conditional equilibrium population size for each species. These coevolutionary principles, applied to a model for resource partitioning, entail that the niche separation between species relative to given niche widths, increases with the variety of available resources and decreases with the number of competing populations. Also, the evolution of character displacement between two species does not proceed far enough to maximize the equilibrium population sizes of the species involved. These results imply that the relationship between the niche overlap (of nearest neighbors) and species diversity is qualitatively different depending on whether the variety of resources at any place covaries with the species diversity there. Without covariation niche overlap increases with species diversity; with covariation overlap may decrease with species diversity. This study provides the beginning of a theory for the convergent evolution of community structure.
Problem-Solving Approaches to Homicide: An Evaluation of the Indianapolis Violence Reduction Partnership

Indianapolis experienced record levels of homicide in the mid-1990s. Officials decided to use a problem-solving strategy that modeled a successful program implemented in Boston. The Indianapolis Violence Reduction Partnership involved a coalition of criminal justice and community agencies using a problem-solving approach to violence. The strategic response included having multiple agencies respond to homicide incidents, directing resources to crimes committed by chronic offenders, and having notification meetings with high-risk probationers and parolees. This research focuses on two issues. First, we describe the impact on homicide. Second, we evaluate the effectiveness of the notification meetings. The results indicate that homicides declined, and the evaluation of the notification meetings shows that arrestees thought the criminal justice system was more effective at responding to crime, however, probationers/parolees were not less likely to recidivate compared to a matched control group. The implicatio...
Elective cesarean delivery: when is it justified?

There has been much recent debate regarding the optimal mode of delivery. In a clinical commentary in the New England Journal of Medicine, the risks and benefits of elective primary cesarean delivery to both the mother and neonate were discussed.1 While a small number of neonates may benefit from elective cesarean delivery, the woman undergoing cesarean incurs increased surgical risk. In addition, there are increased risks to both the mother and neonate in subsequent pregnancies. Trials of labor after cesarean and elective repeat cesareans both carry increased risks.2, 3 Further, the risk of intrauterine fetal demise may be higher in women with a prior cesarean delivery.4
Ecdysone-stimulated secretion from the salivary glands of Manduca sexta

Abstract Metamorphosing larvae of Manduca sexta (Lepidoptera) secrete, during a brief interval, 1–2 ml of fluid which contains up to 2.5 mg of protein, including a 5000-dalton protein which appears at metamorphosis. The protein is secreted in the copious alkaline fluid (pH 9–10), which is released into the burrow. When salivary glands are isolated in vitro in Grace's medium, 20-hydroxyecdysone at first stimulates and then suppresses the synthesis and secretion of the protein.
A rare case of hyponatremia from a hypothalamic lesion in a patient with multiple sclerosis

The syndrome of inappropriate antidiuretic hormone secretion (SIADH) can occur from a variety of neurologic and systemic processes; however, it has rarely been seen in multiple sclerosis (MS). We report a case of SIADH in a patient with MS and compare it with previously reported English-only cases. A 32-year-old woman experienced generalized fatigue followed by confusion and was found to have profound hyponatremia. Her work-up demonstrated SIADH secondary to a discrete enhancing hypothalamic lesion. Despite the seldom occurrence of SIADH in MS, hypothalamic lesions are more common than appreciated and should be considered in patients presenting with hyponatremia or endocrinopathy symptoms.
Effects of properties and location in the plume on droplet diameter for injection in a supersonic stream

The mean droplet diameter in the spray resulting from transverse injection of liquid jets into supersonic airstream was investigated in detail by the use of the diffractively scattered light method. The effects of viscosity, surface tension, jet/freestream dynamic pressure ratio, injector diameter, and location in the plume on the mean droplet diameter were determined. AH tests were performed at A/^ =3.0, with P0 4.2 atm and T0 = 300 K. The injectants used were water, various solutions of glycerine and ethanol in water, and Fluorinert to produce wide variations in viscosity and surface tension. The important results can be summarized as follows: 1) the droplet size has an inverse relation with respect to jet/freestream dynamic pressure ratio, 2) the droplet diameter decreases as the measurement station moves downstream, 3) the smallest droplets are formed at the outer edge of the spray plume, 4) droplet size has a direct relation with respect to surface tension and viscosity of the injectant, and 5) at very high viscosities the jet does not break up into nominally spherical particles. For a certain range of viscosity and dynamic pressure ratio, the breakup of the jet is into ligaments rather than droplets.
Molecular Tagging Using Vibrationally Excited Nitric Oxide in an Underexpanded Jet Flowfield

We report a laser diagnostic technique which relies on planar laser-induced fluorescence of vibrationally excited nitric oxide (NO v=1 ) molecules produced from the 355 nm photodissociation of seeded NO 2 for molecular tagging velocimetry applications. The technique was applied toward an axisymmetric highly underexpanded jet flowfield to yield single-component (streamwise) velocity maps. Detection of the photodissociated NO v=1 molecules would be valuable in flow environments where molecular tagging velocimetry would be highly desirable, but where there are also significant background concentrations of NO. The technique would also be valuable in high-quenching and/or low-velocity flow conditions due to the long-lived nature of the photodissociated NO molecules. Single-shot streamwise velocity uncertainties were about 5% and could be lowered by increasing signal to noise. In addition, the vibrational relaxation of NO was explored in support of a U.S. Air Force Office of Scientific Research Multidisciplinary University Research Initiative project and it was found that the vibrational decay of NO was heavily dependent on collisional vibrational relaxation with oxygen atom formed through NO 2 photodissociation.
Preparation and characterization of microspheres containing the anti-inflammatory agents, indomethacin, ibuprofen, and ketoprofen

Abstract The anti-inflammatory agents, indomethacin, ibuprofen, and ketoprofen, were encapsulated by the solvent evaporation method using polymers such as ethylcellulose, poly(ϵ-caprolactone), poly(methyl methacrylate), polystyrene, and Eudragit RS and RL. In vitro dissolution studies, scanning electron microscopy, and differential scanning calorimetry were used to characterize the microspheres. In contrast to the release of ibuprofen and ketoprofen, the release of indomethacin from ethylcellulose microspheres was too slow for oral use even at high drug loadings. The indomethacin release could be increased by using more permeable polymers or polymer blends. The rates of polymer and drug precipitation during microsphere formation were dependent upon the organic solvent selected. When chloroform was selected as the organic solvent, the drug precipitated before the polymer and indomethacin crystals were visible on the microsphere surface. With methylene chloride, the polymer precipitated before the drug, and drug crystals were not observed. The analysis of the microspheres by differential scanning calorimetry was inconclusive since the drugs dissolved in the molten polymer during the heating step. Indomethacin-poly(ϵ-caprolactone) microspheres were prepared by a melt-dispersion technique without the use of organic solvents.
Trends in Age of Identification and Intervention in Infants with Hearing Loss

Objective In 1993, 11 hospitals in the United States were known to screen more than 90% of newborns for hearing loss. By 2000, approximately 1000 hospitals reported screening at least 90% of their babies. This study was designed to identify trends in the age of identification and intervention for infants and young children with hearing loss in light of expanded implementation of newborn hearing screening. Design Parents of children under 6 yr of age with a confirmed hearing loss were surveyed. The survey instrument was designed to investigate three questions: 1) is the age of identification and intervention earlier for babies whose hearing is screened at birth compared with those whose hearing is not screened; 2) when hearing is screened at birth, do ages of dia-gnosis of hearing loss and intervention meet the guide-lines established in 2000, by the Joint Committee on Infant Hearing (Reference Note 1), and 3) what are the barriers to timely identification and intervention? Six hundred fifty-seven parents received the mailing. Results Responses of 151 parents of children with hearing loss, born between 1996 and 2000, were analyzed. Parents from 41 states provided information. Approximately half the children reported on were screened for hearing loss at birth. Age of identification and hearing aid fitting varied substantially based on degree of hearing loss and whether the cause of hearing loss was known or unknown; however, diagnosis and intervention occurred at an earlier age for infants screened at birth. Findings indicate that when hearing is screened at birth, infants with more severe degrees of hearing loss and an unknown cause tend to be identified and receive intervention within the 2000 timelines proposed by the Joint Committee on Infant Hearing. Barriers to timely identification and intervention are discussed. Conclusions Before widespread implementation of newborn hearing screening, age of identification and intervention were consistently reported to exceed 2 yr of age. The results reported here indicate a trend toward earlier identification and hearing aid fitting with the implementation of newborn hearing screening. Although limited to literate and English speaking respondents, the study provides supporting evidence that newborn hearing screening lowers the ages of identification and intervention.
Using Experiential Tasks to Enhance Cultural Sensitivity Among MFT Trainees

Approximately 60% of accredited MFT master's programs now offer a single course devoted to diversity and oppression, which is noteworthy given that this is not mandated by accreditation standards. For educators and trainers seeking guidance on how to most effectively teach diversity issues and train therapists who will be culturally competent, the MFT literature does an excellent job of providing support for enhancing cultural awareness, for example, cognizance of, insight into, and knowledge about diversity issues. However, far less attention is focused on assisting educators in how to enhance cultural sensitivity, for example, attunement to, emotional resonance with, and meaningful responsiveness to the needs and feelings of others. This article presents a model for how to teach about issues of diversity in ways that promote both cultural awareness and sensitivity but with emphasis on enhancing sensitivity through the use of a series of experiential tasks.
The structural basis of DNA target discrimination by papillomavirus E2 proteins.

The papillomavirus E2 proteins regulate the transcription of all papillomavirus genes and are necessary for viral DNA replication. Disruption of the E2 gene is commonly associated with malignancy in cervical carcinoma, indicating that E2 has a role in regulating tumor progression. Although the E2 proteins from all characterized papillomaviruses bind specifically to the same 12-base pair DNA sequence, the cancer-associated human papillomavirus E2 proteins display a unique ability to detect DNA flexibility and intrinsic curvature. To understand the structural basis for this phenomenon, we have determined the crystal structures of the human papillomavirus-18 E2 DNA-binding domain and its complexes with high and low affinity binding sites. The E2 protein is a dimeric β-barrel and the E2-DNA interaction is accompanied by a large deformation of the DNA as it conforms to the E2 surface. DNA conformation and E2-DNA contacts are similar in both high and low affinity complexes. The differences in affinity correlate with the flexibility of the DNA sequence. Preferences of E2 proteins from different papillomavirus strains for flexible or prebent DNA targets correlate with the distribution of positive charge on their DNA interaction surfaces, suggesting a role for electrostatic forces in the recognition of DNA deformability.
Eccentric-mode excitation of accretion discs.

The development of eccentric-mode resonances in accretion discs within binary systems is simulated. The measured rotational rates of the resulting eccentric discs are found to agree with the observed superhump periods of SU UMa stars. This lends support to the eccentric-disc model of superhump formation. In addition, the decline of the superhump period is found to be explained by the inwards propagation of the eccentric mode. Measurements of superhump periods therefore constrain both the mass ratio of a system and the structure of its accretion disc
Ex-vivo ureteroscopy at the time of live donor nephrectomy.

Abstract Background and Purpose: Potential transplant renal allograft recipients exceed the number of donors. Our institution now considers patients with small, unilateral, nonobstructing, incidental renal calculi for possible renal donation. We adopted ex-vivo ureteroscopy (ExURS) to render these kidneys stone free at the time of renal transplantation. We examined the safety and efficacy of ExURS. Patients and Methods: After confirming a lack of significant metabolic defects on 24-hour urinalysis, 23 patients with small nonobstructing unilateral nephrolithiasis detected on preoperative CT angiography underwent donor nephrectomy. Immediately after cold perfusion, ExURS was performed with ice cold saline irrigation. Retrospective review was performed. Results: Pyeloscopy was successfully performed in all 23 patients. A total of 28 calculi, mean largest diameter 3.9 mm (range 3–6 mm), were visualized in 19 kidneys. Basket extraction and holmium laser lithotripsy was performed in 12 and 6 kidneys, respective...
Compensation Of Tissue-induced PSF Aberrations Using Adaptive Phase Modulation

View Large Image | View Hi-Res Image | Download PowerPoint SlideTissue structures present index mismatches at a variety of spatial scales that can aberrate the focal volume and thus blur cellularly resolved multiphoton images acquired within biological tissues and live animals. We are surveying the types of aberrations that are caused by a variety of tissues to determine the best phase modulation strategies for adaptively correcting the excitation wavefront. A Ti:Sapphire beam is reflected off of a reflective spatial light modulator conjugate to the objective pupil plane. The excitation point-spread-function (PSF) is directly imaged with a separate objective mounted laterally to the optic axis. We find that the fluorescence signal increases with increasing size of the scattering structures. Resolution degradation, however, reaches a maximum with scatterer spatial frequencies at one tenth of the maximal frequency allowed by the focusing objective NA. PSF aberrations can be somewhat compensated by modulating the phase at the back aperture using Zernike polynomials as a basis set for increasing overall image brightness. (See figure for uncorrected vs corrected PSF's through mouse peritoneum.) Initial results show that spherical aberration is a problem, but not the only problem. (Research supported by NIH/NIBIB 41 RR04224 and NIH/NCI R01 CA116583.)
The use of adaptive grids in conjunction with shock capturing methods

The use of shock capturing finite-difference techniques in computing flow fields containing shocks results in a smeared or oscillatory solution in the vicinity of the shocks. This smearing or oscillatory behavior is due to the discretized form of the governing differential equations used to compute the solution. The discretization error can be reduced by a proper clustering of mesh points in the region of the shock and by using shock aligned grids. This paper uses a simple method that was developed earlier to cluster points near the shocks and serves to introduce a new method of generating a shock aligned mesh. Applications to the one-dimensional inviscid Burgers' equation, supersonic flow over a wedge with the associated straight oblique shock, one- and two-dimensional inviscid flows through an expanding duct and the problem of a straight oblique shock in a uniform supersonic freestream are presented. Significant reduction in the oscillatory behavior of the solution is demonstrated.