cssi/SciSciGPT-SciSciNet huggingface dataset:
Parent-Adolescent Congruency in Reports of Adolescent Sexual Behavior and in Communications about Sexual Behavior

Agreement between mothers' and adolescents' reports of communication about sex, satisfaction with the parent-child relationship, maternal disapproval of adolescent sexual activity, and adolescent sexual behavior was investigated in a sample of 745 African American adolescents (ages 14-17) and their mothers. Congruence between the 2 sets of reports tended to be low. Adolescent perceptions and reports were found to be more predictive of adolescent sexual behavior than maternal reports. Mothers tended to underestimate the sexual activity of their teens and teens tended to underestimate their mothers' level of disapproval of their engaging in sexual activity. Reasons for these misperceptions were explored.
Ironing Out MYC in Prostate Cancer

Myc is a growth-promoting protein implicated in the formation of several malignancies, including prostate cancer. Activation of Myc has numerous effects within a cell, including increasing expression of the transferrin receptor 1 (TFRC). As the name implies, the TFRC binds transferrin, a protein
Comminution of single particles in a rigidly-mounted roll mill part 1: mill torque model and energy investment

A mathematical description of single-particle comminution in a rigidly mounted roll mill is presented. When tested against the extensive experimental data pertaining to barite, calcite, dolomite, galena, hematite, limestone and quartz particles, the model of the mill torque correlates reasonably well with the important operating parameters such as roll speed, roll gap, particle size and feed rate. The energy investment for comminuting single particles in the roll mill varies with particle size in the manner of a power function law, whose exponents are in reasonable agreement with published data for fracture of particles in uniaxial compression tests. The calculated Weibull coefficients of uniformity are also generally in conformity with the previous data.
Abstract 514: Targeting of Voltage-gated sodium channel NaV1.5 inhibits cell proliferation and colony formation in breast and ovarian cancer cells.

Breast cancer is the most common and the second leading cause of death in women worldwide while ovarian cancer is the leading cause of gynecological cancers. Breast and ovarian cancer cells have increased proliferation, invasion/metastasis and resistance to programmed cell death due to mutations, altered signaling pathways and deregulated of control mechanism. One of the differences between normal and cancer cells is the changes in the regulation and the function of ion channels. Ion channels are important signaling molecules expressed in a wide range of tissues where they have significant involvement in determining a variety of cellular functions: solute transport, volume control, enzyme activity, secretion, invasion, gene expression, excitation-contraction coupling and intercellular communication. During the malignant transformation, a series of genetic alterations occur, which may also affect the expression and activity of ion channels. This abnormal ion channel activity has been hypothesized to support cell proliferation and tumor growth. Voltage-gated sodium channels (VGNaC) are classically described as critical elements of action potential initiation and propagation in excitable cells. Recent studies showed that VGNaC expression was significantly up-regulated in metastatic human breast cancer cells and tissues, and VGNaC activity potentiated cellular directional motility, endocytosis and invasion. However, the mechanisms of the VGNaC and its functional relevance to breast cancer proliferation are currently not well-known. In this study, we investigated that the effects of downregulation NaV1.5 channel expression by specific RNA interference (ie siRNA) in breast and ovarian cancer cells in vitro. In our work, we first determined the effects of Adult NaV1.5 siRNA and analyzed the effects of Adult and Neonatal (neonatal splice variant of NaV1.5) NaV1.5 silencing by siRNA in BCa cells by Real-Time PCR. Our Real-Time PCR results showed that Adult NaV1.5 channel siRNA reduced the level of NaV1.5 mRNA for MDA-MB-231 BCa cells. We found that knockdown of NaV1.5 channel by siRNA significantly inhibited MDA-MB-231 breast and SKOV3-IP1, SKOV3-TR and HEYA8 ovarian cancer cell proliferation and colony formation. We are currently investigating downstream cellular pathways involved in NaV1.5 mediated proliferation and other cellular functions. In conclusion, our results demonstrate that targeting of NaV1.5 in breast and ovarian cancer cells decreases cell proliferation and colony formation and it may be used as a new therapeutic target in these cancers. Citation Format: Mumin A. Erdogan, Bulent Ozpolat. Targeting of Voltage-gated sodium channel NaV1.5 inhibits cell proliferation and colony formation in breast and ovarian cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 514. doi:10.1158/1538-7445.AM2013-514
Ezrin Is Highly Expressed in Early Thymocytes, but Dispensable for T Cell Development in Mice

Background Ezrin/radixin/moesin (ERM) proteins are highly homologous proteins that function to link cargo molecules to the actin cytoskeleton. Ezrin and moesin are both expressed in mature lymphocytes, where they play overlapping roles in cell signaling and polarity, but their role in lymphoid development has not been explored. Methodology/Principal Findings We characterized ERM protein expression in lymphoid tissues and analyzed the requirement for ezrin expression in lymphoid development. In wildtype mice, we found that most cells in the spleen and thymus express both ezrin and moesin, but little radixin. ERM protein expression in the thymus was differentially regulated, such that ezrin expression was highest in immature thymocytes and diminished during T cell development. In contrast, moesin expression was low in early thymocytes and upregulated during T cell development. Mice bearing a germline deletion of ezrin exhibited profound defects in the size and cellularity of the spleen and thymus, abnormal thymic architecture, diminished hematopoiesis, and increased proportions of granulocytic precursors. Further analysis using fetal liver chimeras and thymic transplants showed that ezrin expression is dispensable in hematopoietic and stromal lineages, and that most of the defects in lymphoid development in ezrin−/− mice likely arise as a consequence of nutritional stress. Conclusions/Significance We conclude that despite high expression in lymphoid precursor cells, ezrin is dispensable for lymphoid development, most likely due to redundancy with moesin.
Assignment of the gene coding for phosphoribosylglycineamide formyltransferase to human chromosome 14.

Purine-requiring Chinese hamster ovary cell auxotrophs of the complementation class ade− E were hybridized with various human cells, and hybrids were isolated under selective conditions in which the retention of the complementing gene on the human chromosome is necessary for survival. Synteny analysis in 72 primary and secondary hybrid clones using isozyme, karyotypic, and biochemical methods provides evidence for an assignment of the gene for phosphoribosylglycineamide formyltransferase (GART, EC 2.1.2.2), deficient in ade− E mutants, to human chromosome 14. The importance of this gene assignment to the development of hypotheses regarding the organization, structure, and regulation of genes involved in the same biosynthetic pathway in mammalian cells is discussed.
A transcript identified by MuA of maize is associated with Mutator activity.

A Mu element, which we designated MuA, was cloned from a maize line with a Mutator background by its homology to the terminal inverted repeats of Mu1. Like other Mu elements, MuA has terminal inverted repeats of approximately 200 by which are homologous to those of Mu1, but the internal region is different. MuA is unique in several aspects, being approximately 5.5 kb in size and the largest Mu element reported to date. It is flanked by 8 by duplications instead of the 9 bp duplications found in most other Mu insertions. The internal sequences of MuA hybridize to restriction fragments that cosegregate with Mutator activity in maize lines showing 1:1 segregation for somatic mutability. The most interesting observation is that a transcript of approximately 3.5 kb identified by the internal sequences of MuA is both qualitatively and quantitatively associated with Mutator activity. This transcript is present in maize lines containing germinal Mutator activity but is undetectable in maize inbreds with no known Mutator activity. The amount of the transcript is decreased in lines that have lost germinal Mutator activity. Northern analysis of maize al-Mum mutant lines that segregate 1:1 for mutability shows that a transcript of the same size is associated with somatic Mutator activity. These data suggest that the 3.5 kb transcript is produced by the autonomous element that confers both germinal and somatic Mutator activity. The possibility that MuA is an autonomous or regulator element of the Mu family is discussed.
Altered Intrathalamic GABAA Neurotransmission in a Mouse Model of a Human Genetic Absence Epilepsy Syndrome

We previously demonstrated that heterozygous deletion of Gabra1, the mouse homolog of the human absence epilepsy gene that encodes the GABAA receptor (GABAAR) α1 subunit, causes absence seizures. We showed that cortex partially compensates for this deletion by increasing the cell surface expression of residual α1 subunit and by increasing α3 subunit expression. Absence seizures also involve two thalamic nuclei: the ventrobasal (VB) nucleus, which expresses only the α1 and α4 subtypes of GABAAR α subunits, and the reticular (nRT) nucleus, which expresses only the α3 subunit subtype. Here, we found that, unlike cortex, VB exhibited significantly reduced total and synaptic α1 subunit expression. In addition, heterozygous α1 subunit deletion substantially reduced miniature inhibitory postsynaptic current (mIPSC) peak amplitudes and frequency in VB. However, there was no change in the expression of the extrasynaptic α4 or δ subunits in VB and, unlike other models of absence epilepsy, no change in tonic GABAAR currents. Although heterozygous α1 subunit knockout increased α3 subunit expression in medial thalamic nuclei, it did not alter α3 subunit expression in nRT. However, it did enlarge the presynaptic vesicular inhibitory amino acid transporter puncta and lengthen the time constant of mIPSC decay in nRT. We conclude that increased tonic GABAA currents are not necessary for absence seizures. In addition, heterozygous loss of α1 subunit disinhibits VB by substantially reducing phasic GABAergic currents and surprisingly, it also increases nRT inhibition by prolonging phasic currents. The increased inhibition in nRT likely represents a partial compensation that helps reduce absence seizures.
Submarine groundwater discharge and nutrient addition to the coastal zone and coral reefs of leeward Hawai'i

Abstract Multiple tracers of groundwater input (salinity, Si, 223Ra, 224Ra, and 226Ra) were used together to determine the magnitude, character (meteoric versus seawater), and nutrient contribution associated with submarine groundwater discharge across the leeward shores of the Hawai'ian Islands Maui, Moloka'i, and Hawai'i. Tracer abundances were elevated in the unconfined coastal aquifer and the nearshore zone, decreasing to low levels offshore, indicative of groundwater discharge (near-fresh, brackish, or saline) at all locations. At several sites, we detected evidence of fresh and saline SGD occurring simultaneously. Conservative estimates of SGD fluxes ranged widely, from 0.02–0.65 m3 m− 2 d− 1at the various sites. Groundwater nutrient fluxes of 0.04–40 mmol N m− 2 d− 1 and 0.01–1.6 mmol P m− 2 d− 1 represent a major source of new nutrients to coastal ecosystems along these coasts. Nutrient additions were typically greatest at locations with a substantial meteoric component in groundwater, but the recirculation of seawater through the aquifer may provide a means of transferring terrestrially-derived nutrients to the coastal zone at several sites.
Real-time measurements of the chemical composition of size-resolved particles during a Santa Ana wind episode, California USA

Size-resolved particle composition, mass and number concentrations, aerosol scattering coefficients, and prevailing meteorological conditions were measured at the Ellen Browning Scripps Memorial Pier located in La Jolla, California on 15 December 1998. Aerosol particles were sampled using a field transportable aerosol time-of-flight mass spectrometer, allowing for the continuous detection and characterization of single particles from a polydisperse sample. An extensive and rapid change in the chemical composition of aerosol particles with aerodynamic diameters between 1.0 and 2.5 μm has been observed during the onset of a Santa Ana Winds condition. Coincident with the observed change in meteorological conditions, a substantial decrease in sea salt particles corresponds to an increase in dust and carbon-containing particles. This paper examines observations of the rapid changes occurring in the chemical composition of single aerosol particles and demonstrates the new types of information that can be obtained by measuring single particle size and composition with high temporal resolution.
Single-layer coating of one mirror of a 90°-rooftop reflector for equal p and s net complex reflection coefficients

Abstract By coating only one of the two orthogonal mirrors of a rooftop reflector (RTR) with a transparent thin film of certain refractive index and thickness, it is possible to equalize the net (two-bounce) complex p and s reflection coefficients at a given angle of incidence. The constraint on the film and mirror substrate optical properties such that this condition is satisfied, the associated film thickness, and the polarization-independent net reflectance of the RTR are all determined. Results are represented graphically at two angles of incidence.
Single-crystal GaN pyramids grown on (1 1 1)Si substrates by selective lateral overgrowth

Abstract Single-crystalline GaN/AlN layers have been grown on (1 1 1)Si substrates and subsequently used as the seeding layer for selective lateral overgrowth on a patterned Si 3 N 4 mask. GaN pyramids are formed during the lateral overgrowth. They are epitactically oriented with respect to the Si substrate with the orientation relationships [1 1 2 0] GaN ‖[ 1 1 0] Si and (0 0 0 1) GaN ‖(1 1 1) Si . The pyramids were characterized by transmission electron microscopy and were found to have a reduced defect density compared with continuous layers of GaN on Si and very few defects in the upper portion. The threading dislocations that originated from the GaN/AlN seeding layer eventually bend through 90° and emerge at the inclined surface. Many of the threading dislocations are actually half-loops which are self-terminating. The results of this study demonstrate that GaN selective lateral overgrowth can be performed on Si substrates and show that the same GaN crystalline quality can be produced on Si as on sapphire and SiC substrates.
Prevalence and distribution of radiographically evident lesions on repository films in the hock and stifle joints of yearling Thoroughbred horses in New Zealand

Abstract AIM: To characterise the prevalence and distribution of radiographic changes in the hocks and stifles of Thoroughbred yearling colts and fillies in New Zealand and compare them with other populations of young horses. METHODS: Repository radiographs taken in New Zealand for the 2003–2006 Thoroughbred national yearling sales were evaluated by two individual readers. The distribution of radiographic changes was classified as left side only, right side only, or bilateral. Lesions were categorised by type, location, and sex of the yearling. Complete sets of hock and stifle radiographs of 1,505 yearlings were evaluated. RESULTS: Osteophytes or enthesophytes were seen radiographically in the distal tarsal joints of 460/1,505 (31%) horses. Osteochondrosis was seen in the tibiotarsal joint of 66/1,505 (4%) horses, and in the femoropatellar joint of 40/1,505 (3%) horses. Radiographic lucency in the distal or axial aspect of the medial femoral condyle was seen in 247/1,505 (16%) horses, and lucencies consis...
Species differences in circulatory responses to nasopharyngeal perfusion with smoke.

Abstract 1. Cardiovascular changes were observed in five species of laboratory mammals during upper airway perfusion with cigarette smoke. 2. Apnoea occured, both before and after vagotomy, in all species. 3. Blood pressure always went up in rabbits, rats and hamsters but was not much affected in cats and guinea-pigs. 4. Before vagotomy heart rate fell in rabbits and rats, rose in hamsters but did not change in cats and guinea-pigs. Vagotomy affected heart rate changes only in rabbits and rats. 5. Results demonstrate markedly different autonomie responses in different species.
Oxidative cyclorelease from soluble polymeric supports.

Single electron oxidation is shown to be a viable method for effecting concomitant cyclization and cleavage (cyclorelease) of a series of polymer bound homobenzylic ethers. Soluble oligonorbornene polymers are stable toward redox chemistry and are isolable through precipitation with methanol, making them excellent supports for this process. These oxidative conditions are also shown to cleave secondary and tertiary alcohols and ethers in a new traceless approach to polymer-supported aldehyde and ketone synthesis.
Adeno-associated virus vectors integrate at chromosome breakage sites

Adeno-associated virus (AAV) vectors transduce cells by multiple pathways, including integration at nonhomologous chromosomal locations by an unknown mechanism. We reasoned that spontaneous chromosome breaks may facilitate vector integration and investigated this in cells containing a specific chromosomal double-strand break created by the endonuclease I-SceI or multiple breaks created by treatment with etoposide or gamma-irradiation. Vector proviruses were found at I-SceI cleavage sites, and sequencing of vector-chromosome junctions detected microhomologies, deletions and insertions that were similar when integration occurred spontaneously at random locations or at induced double-strand breaks. Infection with AAV vectors did not increase mutation rates in normal human cells. Our results establish a mechanism for integration and suggest that AAV vectors can integrate at existing chromosome breaks rather than causing breaks themselves, which has implications for their clinical use.
OPTIMAL NUMBER OF CHOICES PER ITEM—A COMPARISON OF FOUR APPROACHES1

Two approaches in the literature for determining the optimal number of choices for a test item are compared with two new approaches.
11B NMR studies of glassy B2S3

Abstract Temperature dependence of the quadrupolar broadened 11 B NMR spectrum in glassy B 2 S 3 reveals a gradual change in the steric environment of the boron atoms with increasing temperature. Additionally, above 100°C the spectrum is motionally narrowed by atomic reorientation.
The Process of Cognitive Liberation: Cultural Synapses, Links, and Frame Contradictions in the U.S.‐Central America Peace Movement*

Based upon qualitative interviews with thirty-two Central American peace activists, this article elaborates the process of “cognitive liberation” through the application of frame analysis. In addition, I seek to explain the diffusion of this social-psychological state from Central to North America. Attention is given to the role of the church as a common cultural link that functioned as a micro-mobilizing context, which provided missionaries who served as “meso-mobilizing actors.” The term frame contradictions is introduced to specify the condition in which irreconcilable differences between a movement’s frame and its opponent’s frame are exposed, thereby facilitating frame adoption. I conclude that some type of cultural link is necessary for the development of a common frame that can integrate groups cross-nationally and that can provide agents of mobilization to serve as a synapse through which frames can be transmitted from one country to another.
Sexual identity: conflict and confusion in a male adolescent.

This paper presents a conceptual formulation, derived from developmental object relations theory and ego psychology, of the passage in male adolescence that culminates with the achievement of a masculine heterosexual identity. Themes of psychosexuality, male gender attributes, masculinity and object preference, and sexual orientation are discussed with reference to the adolescent stage. Finally, the critical tasks, core conflicts, and internalizations of prior developmental stages, as well as the integration that is required of adolescence proper relative to a sexual identity as heterosexual and masculine, are highlighted through an extensive case illustration of an adolescent male with sexual identity confusion.
Thyroid Hormone Receptor α1 Follows a Cooperative CRM1/Calreticulin-mediated Nuclear Export Pathway

The thyroid hormone receptor α1 (TRα) exhibits a dual role as an activator or repressor of its target genes in response to thyroid hormone (T3). Previously, we have shown that TRα, formerly thought to reside solely in the nucleus bound to DNA, actually shuttles rapidly between the nucleus and cytoplasm. An important aspect of the shuttling activity of TRα is its ability to exit the nucleus through the nuclear pore complex. TRα export is not sensitive to treatment with the CRM1-specific inhibitor leptomycin B (LMB) in heterokaryon assays, suggesting a role for an export receptor other than CRM1. Here, we have used a combined approach of in vivo fluorescence recovery after photobleaching experiments, in vitro permeabilized cell nuclear export assays, and glutathione S-transferase pull-down assays to investigate the export pathway used by TRα. We show that, in addition to shuttling in heterokaryons, TRα shuttles rapidly in an unfused monokaryon system as well. Furthermore, our data show that TRα directly interacts with calreticulin, and point to the intriguing possibility that TRα follows a cooperative export pathway in which both calreticulin and CRM1 play a role in facilitating efficient translocation of TRα from the nucleus to cytoplasm.
Laser-induced fluorescence of se, as, and sb in an electrothermal atomizer.

Trace detection of Se, As, and Sb atoms has been performed by electrothermal atomization laser-induced fluorescence (ETA-LIF) approaches. Production of far-UV radiation necessary for excitation of As atoms at 193.696 nm and Se atoms at 196.026 nm was accomplished by stimulated Raman shifting (SRS) of the output of a frequency-doubled dye laser operating near 230 nm. Both wavelengths were obtained as second-order anti-Stokes shifts of the dye laser radiation and provided up to 10 μJ/pulse, which was shown through power dependence studies to be sufficient for saturation in the ETA. An excited-state direct line fluorescence approach using excitation at 206.279 nm was also investigated for the LIF detection of Se. High-sensitivity LIF of Sb atoms was accomplished using 206.833-nm excitation and detection at 259.805 nm. The accuracy of the ETA-LIF approaches was demonstrated by determining the As and Se content of aqueous reference samples. The limits of detection (absolute mass) were 200 fg by ground-state LI...
Social-Emotional Competence as Support for School Readiness: What Is It and How Do We Assess It?

The overall issue of assessment during early childhood, and its relation to school readiness and other decisions, is currently widely debated. Expanding early childhood education and child care enrollments, better scientific knowledge about early childhood development, and decisions about public spending, necessitate careful consideration of which assessment tools to use, as well as why and when to use them. More specifically, the disconnection between the importance of social and emotional domains of development, and their status within educational programming and assessment, has long been lamented. The last several years have, however, witnessed a blossoming of attention to these areas during early childhood, as crucial for both concurrent and later well-being and mental health, as well as learning and academic success. Teachers view children's "readiness to learn" and "teachability" as marked by positive emotional expressiveness, enthusiasm, and ability to regulate emotions and behaviors. Based on thes...
Profile: Patrick Soon-Shiong

Dr Patrick Soon-Shiong is the Executive Director of the UCLA Wireless Health Institute, and Professor of Microbiology, Immunology, Molecular Genetics and Bioengineering at UCLA. He is a fellow of both the American College of Surgeons and the Royal College of Physicians and Surgeons of Canada. He serves on the Board of Directors for the National Institute of Transplantation, the Technology Council for the Center for Cancer Nanotechnology Excellence at Northwestern University, which is part of the National Cancer Institute's (NCI) five-year initiative for nanotechnology in cancer research. He serves on the RAND Health Board of Advisors and the President's Council at RAND, the Board of Trustees for the Saint John's Health Center, the Advisory Board of the California NanoSystems Institute at UCLA, the Advisory Board for the Institute for Technology Advancement (ITA) at UCLA School of Engineering, the Board of Councillors of the USC Viterbi School of Engineering, and the Arizona Commerce Authority Board. He is a founding board member of the Dossia Foundation, a non-profit consortium of large employers (Wal-Mart, AT&T, BP America, Intel, Pitney Bowes, Cardinal Health, Sanofi-Aventis, Applied Materials, and Vanguard) that seek to enhance consumer engagement in their own healthcare through use of personal health records. In 2009, he was appointed by Attorney General Cuomo to the board of FAIR Health, a new not-for-profit entity to facilitate nationwide reform of consumer reimbursement for out of network healthcare charges.
On the size of vote trades

What do the preceding results tell us for democratic theory? First, that a majority can always defend itself against 2-issue special interest vote trades with a coalition no larger than that used by the minority. In terms of numbers counter-trades are no harder to organize than 2-issue special interest vote trades. Since we might expect that 2-issue vote trades are easier to organize than trades involving 3 or more issues, this result is encouraging. The author is currently conducting research on the incidence of various types of strategic voting in the U.S. Congress. This research indicates that voter agreements, when they can be identified, are usually quite simple. Thus 2-issue trades may be found to comprise the bulk of the vote trading that takes place in the Congress. If so, then in those cases the majority needs a coalition no larger than that used by the minority to block vote trades that are harmful to its interests. However, for special interest trades involving 3 or more issues, Figure 3 demonstrates that the size advantage may rest with the minority. If size is a major consideration in organizing vote trading coalitions, we should expect then that more of these trades will be successful than 2-issue special interest trades. Given the complexity of trades involving 3 or more issues, it seems reasonable to expect that in Congress such trades would usually be transacted at the staff or committee level. Special interest vote trading carried out at this level would then appear to be the most difficult kind to block. Thus trade size is both important for the theory of vote trading and may also be an important determinant of how vote trading is practiced.
“Thinking without thinking” about natalizumab and PML

The novel multiple sclerosis (MS) therapeutic natalizumab has taken neurologists and their MS patients on a roller-coaster ride: initial encouraging efficacy data led to expedited release in the United States, followed by suspension of dosing with the unexpected occurrence of progressive multifocal leukoencephalopathy (PML) in three clinical trial participants. The drug was re-released in 2006, in a restricted distribution format. Aside from PML, natalizumab treatment was not associated with opportunistic infections, suggesting the possibility that PML in these individuals was mechanism-based, and was not a consequence of generalized immunosuppression. This commentary proposes a hypothesis to account for PML in natalizumab-treated patients.
Multiplicity of mechanisms of serotonin receptor signal transduction

The serotonin (5-hydroxytryptamine, 5-HT) receptors have been divided into 7 subfamilies by convention, 6 of which include 13 different genes for G-protein-coupled receptors. Those subfamilies have been characterized by overlapping pharmacological properties, amino acid sequences, gene organization, and second messenger coupling pathways. Post-genomic modifications, such as alternative mRNA splicing or mRNA editing, creates at least 20 more G-protein-coupled 5-HT receptors, such that there are at least 30 distinct 5-HT receptors that signal through G-proteins. This review will focus on what is known about the signaling linkages of the G-protein-linked 5-HT receptors, and will highlight some fascinating new insights into 5-HT receptor signaling.
Variability in Mechanical Properties of Insect Tracheal Tubes

Insects employ a network of tracheal tubes to transport oxygen directly to every cell of the body. During respiration, these tubes undergo localized and rhythmic deformations due to local variation in their structural and mechanical properties. In order to elucidate the mechanisms of insect respiration, mechanical tests on ring sections of tracheal tubes extracted from American Cockroaches were conducted. A total of 33 specimens collected from 14 tracheal tubes located in the upper thorax of the insects were successfully tested. The ultimate tensile strength (22.6 ± 13.3 MPa), ultimate strain (1.57 ± 0.68 %), elastic modulus (1740 ± 840 MPa), and toughness (0.175 ± 0.156 MJm−3) were measured in the radial direction. The mechanical properties of ring sections excised from the same tracheal tube were shown to exhibit less variability than those of ring sections excised from different tracheal tubes. The results of this study will help in determining the relationship between the mechanics and structure of tracheal tube thus ultimately leading to the creation of novel bio-inspired micro-systems.© 2013 ASME
Heat Transfer in Rotating Narrow Rectangular Ducts With Heated Sides Oriented at 60° to the r-z Plane

Gas turbine blade life is often limited by the effectiveness of the cooling in the trailing edge convective cavity, which generally has a narrow cross-section. Previous research on rotational effects considered cavity shapes quite different from those of typical trailing edge cavities. In this research, experiments were conducted to determine the effect of rotation on heat transfer in ducts of narrow cross-section (height-to-width ratio of 1:10), oriented with the heated sides at 60° to the r-z plane. In the experiment, a high-molecular-weight gas (Refrigerant-134A) at ambient pressure and temperature conditions was used to match the dimensionless parameters at engine conditions. Thin foil heaters were used to produce a constant heat flux at the long sides of the duct; the narrow sides were unheated. Duct Reynolds numbers were varied up to 20,000; rotation numbers were varied up to 0.25. The test results show the effect of rotation and aspect ratio on duct leading and trailing side heat transfer. In addition, the results show the variation in heat transfer coefficient with transverse location in the duct, demonstrating the effect of rotation not only on lead and trail side heat transfer, but also on forward and aft end heat transfer.Copyright © 2000 by ASME
Foreign direct investment and country risk: Further empirical evidence

Global political and economic changes over the last decade have resulted into massive capital inflows to developing countries, most of these flows are foreign direct investments. In light of threats of political instability in the forms of civil wars, illegal capital flight, financial market instability, and political corruption, etc., further assessment of country risk is warranted. We examine the relationship between FDI and political and economic risks for 26 countries for the years 1992, 1993, and 1994 by using regression analysis and cross section data. The results indicate a significant relationship between FDI and these risks. This study provides more reliable estimates by using a current and eclectic measurement of risks represented by Euromoney indexes of political and economic risks. In the previous studies the perception of risk was narrowly defined and also political instability events were mistakenly interpreted as political risks.
The utility of transactional and transformational leadership for predicting performance and satisfaction within a path-goal theory framework

In a test of hypotheses derived from the integration of principles of path-goal theory (House, 1996) and transformational leadership theory (Bass, 1985), data collected from 179 high school teachers and their principals were examined with hierarchical regression analysis. Augmentation analysis indicated that transactional leadership had a stronger role in explaining unique criterion variance beyond the contribution of transformational leadership, than did transformational leadership relative to transactional leadership. In addition, both the transactional and transformational leadership had a negative interactive relationship for predicting the outcome of performance, such that leader vision and leader intellectual stimulation were more positively correlated with employee performance when leader use of contingent reward was low. These augmentation effects, in conjunction with the findings of negative moderation, suggest that transactional leadership may have greater potential predictive value than previously assumed.
Optional two-part tariffs constrained by price caps

Abstract Cost reducing incentives possibly generated by price cap regulation may invoke allocative inefficiencies. However, if the regulated firm can offer optional (two-part) tariffs in addition to the price caps, then Pareto optimal outcomes will be reached under quite general conditions.
A rare garnet-tourmaline-sillimanite-biotite-ilmenite-quartz assemblage from the granulite-facies region of south-central Massachusetts

A rare lithology consisting of garnet-tourmaline-sillimanite-biotite-ilmenite-quartz has been found within the granulite-facies region of south-central Massachusetts. The homogeneous, Ti-rich oxy-dravitic tourmaline, X Mg = Mg/(Mg + Fe) = 0.72–0.77, falls into the alkali group, and is similar in composition to lower grade tourmaline found in corresponding metapelitic rocks in Maine. Charge-balancing calculations and binary diagrams suggest that, like biotite in the region, tourmaline has undergone deprotonation by means of the exchange vectors AlOR −1 (OH) −1 and TiO 2 R −1 (OH) −2 , where R represents Fe + Mg. The restriction of a concordant tourmaline-rich horizon in otherwise tourmaline-free rocks of this granulite-facies region suggests that either: (1) B, released during prograde fluid-absent dehydration reactions of muscovite and biotite, was locally available in a fluid phase or melt for later crystallization near the peak of granulite-facies metamorphism along pathways that provided a conduit for fluid migration; or (2) that this is simply a B-rich compositional horizon (tourmalinite) that survived anatexis and granulite-facies metamorphism and that records the incipient conditions of tourmaline breakdown and subsequent recrystallization near or post-peak metamorphism.
Magnetic Field Dependence of the Knight Shift in Aluminum

The magnetic field dependence of the Knight shift in high-purity single crystals of aluminum at low temperatures shows an oscillatory behavior. The oscillations are measured for the field directed along the [111] axis of the crystal and are found to match the de Haas-van Alphen frequency of electrons on the third zone of the Fermi surface. Details of the method of analysis necessary to obtain the wave-function amplitude for this set of carriers are given.
Determining elasticity from single polymer dynamics

The ability to determine polymer elasticity and force–extension relations from polymer dynamics in flow has been challenging, mainly due to difficulties in relating equilibrium properties such as free energy to far-from-equilibrium processes. In this work, we determine polymer elasticity from the dynamic properties of polymer chains in fluid flow using recent advances in statistical mechanics. In this way, we obtain the force–extension relation for DNA from single molecule measurements of polymer dynamics in flow without the need for optical tweezers or bead tethers. We further employ simulations to demonstrate the practicality and applicability of this approach to the dynamics of complex fluids. We investigate the effects of flow type on this analysis method, and we develop scaling laws to relate the work relation to bulk polymer viscometric functions. Taken together, our results show that nonequilibrium work relations can play a key role in the analysis of soft material dynamics.
Interview of Wives: A Necessary Adjunct in the Evaluation of Impotence

Clinical reports have suggested that involving wives in the evaluation of their husbands' sexual dysfunction is important, but data are scant. Our study shows that interviews with wives (or other significant sexual partners) are essential, not only for assessing the possible role of marital conflict in impotence etiology, but also for correcting patients' misinformation and for gaining insight into the wives' sexual and psychological dynamics which will be necessary for optimal referral if medical treatment for the impotence is not indicated. Over a period of six months, 49 currently married or substantially involved men were evaluated for impotence in our Male Sexual Dysfunction Unit. Forty of their wives or primary sex partners were interviewed by the Unit psychologist yielding significant medical and psychosocial information and concrete details of erectile and ejaculatory performance. In several cases, this information contradicted that obtained from the patients themselves. In many instances, the information was an important supplement and affected treatment recommendations.
Micromolar L-2-amino-4-phosphonobutyric acid selectively inhibits perforant path synapses from lateral entorhinal cortex.

Abstract Transverse slices of the rat hippocampus were used to examine the ability of phosphonate analogues of acidic amino acids to inhibit perforant path synaptic transmission. Micromolar concentrations of l -2-amino-4-phosphonobutyric acid (APB), an analogue of l -glutamic acid, inhibited transmission from the lateral entorhinal cortex. Two other less-sensitive components were detected in projections from the medial entorhinal cortex. The component from the lateral entorhinal cortex showed high stereospecificity for the l -isomer of APB and was relatively insensitive to phosphonate homologues of shorter and longer chain length.
Increasing predictive accuracy by prefetching multiple program and user specific files

Recent increases in CPU performance have outpaced increases in hard drive performance. As a result, disk operations have become more expensive in terms of CPU cycles spent waiting for disk operations to complete. File prediction can mitigate this problem by prefetching files into cache before they are accessed However, incorrect prediction is to a certain degree both unavoidable and costly. We present the Program-based and User-based Last n Successors (PULnS) file prediction model that identifies relationships between files through the names of the programs and the users accessing them. Our simulation results show that, in the worst case, PULnS makes at least 20% fewer incorrect predictions and roughly the same number of correct predictions as the last-successor model.
Plant‐specific mitotic targeting of RanGAP requires a functional WPP domain

*Summary The small GTPase Ran is involved in nucleocytoplasmic transport, spindle formation, nuclear envelope (NE) formation, and cell-cycle control. In vertebrates, these functions are controlled by a three-dimensional gradient of Ran-GTP to Ran-GDP, established by the spatial separation of RanGTPase-activating protein (RanGAP) and the Ran guanine nucleotide exchange factor RCC1. While this spatial separation is established by the NE during interphase, it is orchestrated during mitosis by association of RCC1 with the chromosomes and RanGAP with the spindle and kinetochores. SUMOylation of vertebrate RanGAP1 is required for NE, spindle, and centromere association. Arabidopsis RanGAP1 (AtRanGAP1) lacks the SUMOylated C-terminal domain of vertebrate RanGAP, but contains a plant-specific N-terminal domain (WPP domain), which is necessary and sufficient for its targeting to the NE in interphase. Here we show that the human and plant RanGAP-targeting domains are kingdom specific. AtRanGAP1 has a mitotic trafficking pattern uniquely different from that of vertebrate RanGAP, which includes targeting to the outward-growing rim of the cell plate. The WPP domain is necessary and sufficient for this targeting. Point mutations in conserved residues of the WPP domain also abolish targeting to the nuclear rim and the cell plate, suggesting that the same mechanism is involved in both targeting events. These results indicate that plant and animal RanGAPs undergo different migration patterns during cell division, which require their kingdom-specific targeting domains.
Miniaturization of specimens for mechanical testing

Etude des proprietes de traction sur des echantillons «miniatures»: disques de 3 mm de diametre sur une epaisseur de 0,25 mm qui sont necessaires pour determiner l'influence d'une irradiation ionique sur les proprietes mecaniques des materiaux utilises dans la construction des reacteurs de fusion. Presentation de resultats d'essais concernant la ductilite, les proprietes de fatigue et la transition ductile-fragile dans des alliages commerciaux d'aluminium, dans des alliages a base de cuivre et dans un acier ferritique
On the accuracy of stratospheric aerosol extinction derived from in situ size distribution measurements and surface area density derived from remote SAGE II and HALOE extinction measurements

In situ stratospheric aerosol measurements, from University of Wyoming optical particle counters (OPCs), are compared with Stratospheric Aerosol Gas Experiment (SAGE) II (versions 6.2 and 7.0) and Halogen Occultation Experiment (HALOE) satellite measurements to investigate differences between SAGE II/HALOE-measured extinction and derived surface area and OPC-derived extinction and surface area. Coincident OPC and SAGE II measurements are compared for a volcanic (1991-1996) and nonvolcanic (1997 2005) period. OPC calculated extinctions agree with SAGE II measurements, within instrumental uncertainty, during the volcanic period, but have been a factor of 2 low during the nonvolcanic period. Three systematic errors associated with the OPC measurements, anisokineticity, inlet particle evaporation, and counting efficiency, were investigated. An overestimation of the OPC counting efficiency is found to be the major source of systematic error. With this correction OPC calculated extinction increases by 15 30% (30 50%) for the volcanic (nonvolcanic) measurements. These changes significantly improve the comparison with SAGE II and HALOE extinctions in the nonvolcanic cases but slightly degrade the agreement in the volcanic period. These corrections have impacts on OPC-derived surface area density, exacerbating the poor agreement between OPC and SAGE II (version 6.2) surface areas. This disparity is reconciled with SAGE II versionmore » 7.0 surface areas. For both the volcanic and nonvolcanic cases these changes in OPC counting efficiency and in the operational SAGE II surface area algorithm leave the derived surface areas from both platforms in significantly better agreement and within the 40% precision of the OPC moment calculations.« less
Weight Initialization for Simultaneous Recurrent Neural Network Trained with a Fixed-point Learning Algorithm

This letter presents a study of the Simultaneous Recurrent Neural network, an adaptive algorithm, as a nonlinear dynamic system for static optimization. Empirical findings, which were recently reported in the literature, suggest that the Simultaneous Recurrent Neural network offers superior performance for large-scale instances of combinatorial optimization problems in terms of desirable convergence characteristics improved solution quality and computational complexity measures. A theoretical study that encompasses exploration of initialization properties of the Simultaneous Recurrent Neural network dynamics to facilitate application of a fixed-point training algorithm is carried out. Specifically, initialization of the weight matrix entries to induce one or more stable equilibrium points in the state space of the nonlinear network dynamics is investigated and applicable theoretical bounds are derived. A simulation study to confirm the theoretical bounds on initial values of weights is realized. Theoretical findings and correlating simulation study performed suggest that the Simultaneous Recurrent Neural network dynamics possesses desirable stability characteristics as an adaptive recurrent neural network for addressing static optimization problems.
Meta Aircraft Flight Dynamics

A meta aircraft is an air vehicle composed of a set of independent aircraft that are connected together in flight to form a larger composite aircraft. This paper explores the dynamics of meta aircraft systems with a focus on the changes in the aircraft flight dynamic modes and flexible modes of the system. Specifically, when aircraft are connected, basic flight dynamic modes such as the phugoid, short period, dutch roll, spiral, and roll modes change as a function of the number of connected aircraft. For aircraft connected in a wing-tip-to-wing-tip configuration, the longitudinal modes remain largely invariant with respect to the number of aircraft, whereas lateral modes are variable for both tip-to-tail and wing-tip-to-wing-tip connection configurations. In addition, connected aircraft exhibit complex flexible modes that change based on the characteristics of the connection joint and the number of connected aircraft. These conclusions are reached using a rigid six-degree-of-freedom representation for a s...