cssi/SciSciGPT-SciSciNet huggingface dataset:
Scholars and social media: tweeting in the conference backchannel for professional learning

Social media are fundamentally changing core practices in various industries. Although surveys indicate that social media are impacting social scientists, we know little about how education scholars, specifically, use social media for their work or professional learning. This article explores how educational scholars incorporated the social media, Twitter, as a conference backchannel. Using qualitative interview data collected from members of the American Educational Research Association (AERA) and considering previous analysis of AERA conference tweet data, we describe participants’ purposes and practices and their perceptions of how using this social media impacts participation in the conference community. We discuss implications for those concerned with research dissemination, faculty professional development, and academic identity.
A three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses.

Background: Misalignment of an articulated ankle-foot orthosis joint axis with the anatomic joint axis may lead to discomfort, alterations in gait, and tissue damage. Theoretical, two-dimensional models describe the consequences of misalignments, but cannot capture the three-dimensional behavior of ankle-foot orthosis use. Objectives: The purpose of this project was to develop a model to describe the effects of ankle-foot orthosis ankle joint misalignment in three dimensions. Study design: Computational simulation. Methods: Three-dimensional scans of a leg and ankle-foot orthosis were incorporated into a link segment model where the ankle-foot orthosis joint axis could be misaligned with the anatomic ankle joint axis. The leg/ankle-foot orthosis interface was modeled as a network of nodes connected by springs to estimate interface pressure. Motion between the leg and ankle-foot orthosis was calculated as the ankle joint moved through a gait cycle. Results: While the three-dimensional model corroborated predictions of the previously published two-dimensional model that misalignments in the anterior -posterior direction would result in greater relative motion compared to misalignments in the proximal -distal direction, it provided greater insight showing that misalignments have asymmetrical effects. Conclusions: The three-dimensional model has been incorporated into a freely available computer program to assist others in understanding the consequences of joint misalignments. Clinical relevance Models and simulations can be used to gain insight into functioning of systems of interest. We have developed a three- dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses. The model has been incorporated into a freely available computer program to assist understanding of trainees and others interested in orthotics.
Dissecting the cosubstrate structure requirements of the Staphylococcus aureus aminoglycoside resistance enzyme ANT(4

Aminoglycosides are important antibiotics used against a wide range of pathogens. As a mechanism of defense, bacteria have evolved enzymes able to inactivate these drugs by regio-selectively adding a variety of functionalities (acetyl, phospho, and nucelotidyl groups) to their scaffolds. The aminoglycoside nucleotidyltransferase ANT(4') is one of the most prevalent and unique modifying-enzymes. Here, by TLC, HRMS, and colorimetric assays, we demonstrate that the resistance enzyme ANT(4') from Staphylococcus aureus is highly substrate and cosubstrate promiscuous. We show that deoxy-ribonucleotide triphosphates (dNTPs) are better cosubstrates than NTPs. We demonstrate that the position of the triphosphate group (5' and not 3') on the ribose/deoxyribose ring is important for recognition by ANT(4'), and that NTPs with larger substituents at the 3'-position of the ribose ring are not cosubstrates for ANT(4'). We confirm that for all aminoglycosides tested, the respective nucleotidylated products are completely inactive. These results provide valuable insights into the development of strategies to combat the ever-growing bacterial resistance problem.
Client Characteristics Associated with Not Keeping Appointments for Public Health Nursing Home Visits

Home visits have been identified as an intervention strategy for high-risk pregnant women. A necessary component of this intervention strategy is for the women to be home for the visit with the nurse. The purpose of this study was to identify factors associated with women not keeping their home visit appointments with a public health nurse. Subjects were 232 low-income high-risk pregnant women who received at least one home visit by a public health nurse. Younger age, more stressful life events, receipt of medical assistance, inadequacy of prenatal care, noncompliance with health recommendations, and longer gestational time were associated with not keeping public health nursing appointments. While this study provides some insight into the factors associated with women not keeping their appointments with the public health nurse, further investigation is warranted to identify strategies to reduce the incidence of not-kept appointments.
Posterior cruciate ligament injuries.

Medical knowledge concerning the posterior cruciate ligament (PCL) injured knee has lagged behind that of the anterior cruciate ligament (ACL) injured knee. Interest in the PCL has increased in recent years and the PCL is now a major focus of Orthopedic sports medicine research. Significant debate continues over whether or not the PCL needs to be reconstructed and if the reconstruction of the injured PCL results in improved functional outcome of the knee. There are several different techniques of reconstruction, each having their own merits, but none have been accepted as the “gold standard” technique of reconstruction.
The role of hydroxyl group acidity on the activity of silica-supported secondary amines for the self-condensation of n-butanal.

The catalytic activity of secondary amines supported on mesoporous silica for the self-condensation of n-butanal to 2-ethylhexenal can be altered significantly by controlling the Bronsted acidity of M--OH species present on the surface of the support. In this study, M--OH (M=Sn, Zr, Ti, and Al) groups were doped onto the surface of SBA-15, a mesoporous silica, prior to grafting secondary propyl amine groups on to the support surface. The catalytic activity was found to depend critically on the synthesis procedure, the nature and amount of metal species introduced and the spatial separation between the acidic sites and amine groups. DFT analysis of the reaction pathway indicates that, for weak Bronsted acid groups, such as Si--OH, the rate-limiting step is C--C bond formation, whereas for stronger Bronsted acid groups, such as Ti and Al, hydrolysis of iminium species produced upon C--C bond formation is the rate-limiting step. Theoretical analysis shows further that the apparent activation energy decreases with increasing Bronsted acidity of the M--OH groups, consistent with experimental observation.
Differences in delay discounting between smokers and nonsmokers remain when both rewards are delayed

Rationale When offered a choice between a small monetary reward available immediately (SmallNow) versus a larger reward available after a delay (LargeLater), smokers select the SmallNow alternative more than nonsmokers. That is, smokers discount the value of the LargeLater reward more than nonsmokers.
A study of nicotine release from tobacco hairy roots by transient technique

A material balancing method for determining the productivity of nicotine-releasing Nicotiana tabacum hairy roots is presented. Diffusive nicotine release from the intracellular environment of N. tabacum to its medium is based upon an equilibrium partitioning process. By removing nicotine from a culture's medium, subsequent transient release from the tissue is induced, as is the heightened production of nicotine. Under normal conditions, sixteen hours is required for releasing tissue to re-establish equilibrium with the medium. 100 ppm of the surfactant Triton X-100 was used to enhance the rate of nicotine release and to reduce the return to equilibrium to four hours without toxic side-effects.
Novel Triphosphate Phosphohydrolase Activity of Clostridium thermocellum TTM, a Member of the Triphosphate Tunnel Metalloenzyme Superfamily

Triphosphate tunnel metalloenzymes (TTMs) are a newly recognized superfamily of phosphotransferases defined by a unique active site residing within an eight-stranded β barrel. The prototypical members are the eukaryal metal-dependent RNA triphosphatases, which catalyze the initial step in mRNA capping. Little is known about the activities and substrate specificities of the scores of TTM homologs present in bacterial and archaeal proteomes, nearly all of which are annotated as adenylate cyclases. Here we have conducted a biochemical and structure-function analysis of a TTM protein (CthTTM) from the bacterium Clostridium thermocellum. CthTTM is a metal-dependent tripolyphosphatase and nucleoside triphosphatase; it is not an adenylate cyclase. We have identified 11 conserved amino acids in the tunnel that are critical for tripolyphosphatase and ATPase activity. The most salient findings are that (i) CthTTM is 150-fold more active in cleaving tripolyphosphate than ATP and (ii) the substrate specificity of CthTTM can be transformed by a single mutation (K8A) that abolishes tripolyphosphatase activity while strongly stimulating ATP hydrolysis. Our results underscore the plasticity of CthTTM substrate choice and suggest how novel specificities within the TTM superfamily might evolve through changes in the residues that line the tunnel walls.
Microvilli on sea urchin eggs: a second burst of elongation.

Abstract A scanning EM study reveals about 300,000 microvilli on each egg of the sea urchin Strongylocentrotus droebachiensis . The microvilli are about 0.2 μm long before fertilization, elongate to about 0.5 μm soon after fertilization (the “first burst” of microvillus elongation), and subsequently elongate again about midway between fertilization and first cell division (the “second burst” of elongation). The second burst occurs during a discrete 30-min period and results in some microvilli being as long as 10 μm, although the average length is about 1.8 μm. The surface area of the egg following the second burst is about 2.7 times the area of the unfertilized egg.
Czech and Slovak women and political leadership

Abstract Women have played an important role in social movements and public life throughout the history of the Czech and Slovak nations. However, they have seldom been well represented among those who exercise power. This article reviews the historical record of women's role in public life, including women's movements, in the nineteenth century, in the republic of Czechoslovakia, and in the Communist period. Political, economic and cultural contrasts between the Czech Lands and Slovakia are longstanding, and continue in the present, when the two areas have become separated political entities. Factors common to both the Czech Lands and Slovakia limit women's interest in political leadership and their acceptance as serious candidates for high political office.
Some effects of excess methionine on lipide metabolism in the rat.

Abstract Wistar rats fed a synthetic diet containing 4.8% excess dl -methionine for 28 days showed increased serum and carcass cholesterol, and decreased total carcass lipide compared to pair-fed controls. The incorporation of acetate-2-C 14 into hepatic cholesterol in vivo and in vitro was significantly greater in the methionine-fed animals, but incorporation of acetate-2-C 14 into fatty acids of adipose tissue was much less than in controls. In methionine-fed animals, liver fatty acid was unchanged, and liver cholesterol increased in comparison to the levels observed in pair-fed controls. Methionine-fed and control rats produced respiratory C 14 O 2 from injected labeled acetate at approximately the same rate; however, liver slices from animals fed excess amino acid showed a depression in the production of C 14 O 2 from acetate-2-C 14 when compared to control slices. The results were discussed with reference to some similarities to the derangements in fat metabolism in the diabetic rat.
Effects of a change of terrain height and roughness on a wind profile

We have measured profiles of an onshore wind 200 m upwind and 200 m downwind from an abruptly rising shore using a remote-sensing Doppler lidar anemometer. Data were taken at heights between 4.7 and 66.5 m above sea level. Results show that the onshore velocity vector slopes upward 16.6 to 9.6°, the amount depending on the height of measurement, due to the combined effects of a 1.7-m high bluff shoreline and the frictionally decelerated flow over land. The profile 200 m inland has the expected deceleration at lower levels because of increased surface roughness and implies a velocity vector at 66.5 m height with an upward slope of approximately 18° (2.6 m s-1 upward component, 8.4 m s-1 vector magnitude), an acceleration to 0.3 m s-1 greater than the upwind value, or a combination of both effects. All three options are consistent with mass continuity. The experiment exhibits the usefulness and limitations of a backscatter Doppler lidar for boundary-layer profile measurements in a horizontally inhomogeneous environment.
Locus of control and HIV risk among a sample of Mexican and Puerto Rican women.

The disproportionate impact of HIV/AIDS on Hispanic women in the United States has been variously attributed to a failure to utilize protective measures due to low levels of HIV knowledge, a denial or minimization of risk, and conflicts with cultural norms. It has been hypothesized that women's relative lack of power in relationships may be associated with higher risk sexual behavior. We examined the relationship between higher risk sexual behavior and perceived locus of control in sexual relationships among a sample of Puerto Rican and Mexican women. We interviewed 71 women of self-reported Mexican ethnicity in San Diego, California, and 79 women of self-reported Puerto Rican ethnicity in Cleveland, Ohio, to examine the relationship between HIV risk, HIV knowledge, and locus of control. Univariate logistic regression indicates that among Puerto Rican women, the perception that locus of control in a sexual relationship resides in the male partner was significantly associated with increased HIV risk, while younger age was significantly associated with increased risk among Mexican women only. In a combined sample of both Puerto Rican and Mexican women, multiple logistic regression analysis indicates that younger age, increased length of residence in the United States, and an other-focused locus of control are significantly associated with increased HIV risk. Women who have been in the United States for relatively longer periods of time may be more likely to integrate U.S. sexual norms into their own behavior and may, as a consequence, be at higher risk of HIV infection. Increased HIV prevention efforts must be made available to Mexican and Puerto Rican women born outside of the United States. These prevention efforts must necessarily focus not only on HIV prevention strategies, but also on the dynamics within male–female intimate relations. Increased attention to younger Puerto Rican and Mexican women is also needed.
Probability-based criteria for structural design

Abstract Probability-based loading and resistance criteria are presented that are suitable for routine safety checking in design. The criteria are based on a comprehensive analysis of statistical data on structural loads and resistances and an examination of levels of reliability implied by the use of current design standards and specifications. The criteria are intended to be used in specifications that are oriented towards limit states design.
Positive ion structure in 3He-rich liquid helium mixtures☆

Abstract The structure of positive ions in impure 3 He is investigated. We predict a “halo” of 4 He around the ion. We use the halo to interpret recent experiments on ion mobility in 3 He. Other properties of the halo are studied.
Bringing poetry into staff development.

"Quello che mai fue detto d'alfcuna," words from Dante, "strive to say which was never said by anyone." This is the art of true verbal expression, the essence of poetry. Poet W. H. Auden once wrote that "poetry can open spaces of meaning for the human spirit that is more intimate to other human beings than it is to ourselves" (Auden, 1968). Poetry has many definitions. To some, it is the rhythmic verse they remember from grade school or from Mother Goose. To others, poetry is a verse of meter and measure, of balance and harmony. However, to most individuals, poetry is the ultimate expression of human emotion. Roy (1999) believed that nursing is in need of poetry, in order to evoke the deepest of images, fears, questions, and quests of the human spirit and the nursing profession. This article examines the use of poetry and how it might be incorporated into staff education.
The Effects of the George W. Bush Presidency on Partisan Attitudes

Evidence from the eight years of the George W. Bush administration confirms that the public standing of the president's party rises and falls in concert with popular evaluations of his job performance. Reactions to the president affect the favorability ratings of his party, party identification measured individually and at the aggregate level—particularly among younger voters—as well as the party's electoral performance. Bush's second term, which provoked the longest period of low and downward-trending approval ratings on record, thus inflicted considerable damage on the Republican Party's image, popular support, and electoral fortunes.
MANAGEMENT OF AN INFECTED HEMATOMETROCOLPOS IN A PATIENT WITH CONGENITAL ADRENAL HYPERPLASIA AND VAGINAL STENOSIS

A 12-year-old girl presented with abdominal pain associated with menses. She had a history of congenital adrenal hyperplasia, and had undergone clitoral recession and posterior flap vaginoplasty at age 18 months. Evaluation revealed abdominal tenderness and pyuria. She was treated for urinary tract infection. The pain worsened and was associated with fever, and the patient was seen by a urologist. Ultrasound demonstrated a pelvic mass consistent with a dilated, fluid filled vagina. The patient underwent endoscopy through the common urogenital sinus but the vaginal introitus could not be identified. Symptoms improved significantly on intravenous antibiotics, and she was referred for further evaluation. Physical examination demonstrated suprapubic tenderness, an enlarged clitoris and a single perineal opening. Rectal examination revealed a large bulging mass anteriorly. Urinalysis showed no infection. The perineal opening was cannulated and a voiding cystourethrogram showed mass effect with anterior displacement of the bladder. Despite several bladder fillings and voidings, no contrast material entered the vagina. MRI was performed to characterize the suspected hematometrocolpos. The sagittal fast spin echo series showed a large midline pear-shaped, fluid filled mass displacing and compressing the bladder and rectum (see figure). Superiorly the mass was contiguous with a small fluid filled uterus and inferiorly it appeared obstructed just above the urogenital diaphragm. The signal intensity of the vaginal and uterine contents was suggestive of proteinaceous fluid and did not follow the signal characteristics of simple blood products. Based on MRI and history, infected hematometrocolpos due to vaginal stenosis was suspected. At cystoscopy the bladder neck was 2 cm. from the perineal opening of the urogenital sinus. It was elevated due to compression from the posterior mass. The bladder contained abundant whitish debris but was otherwise unremarkable. The vaginal introitus was not visible along the urogenital sinus. Based on the MRI and using real-time transabdominal ultrasound guidance, the stifF end of a 0.038-inch polytetrafluorwthylene coated guide wire was passed through the wall of the urogenital sinus and into the vagina. The tract
Emergency Contraception: The Pill’s Little-known Secret Goes Public

Thanks to a recent and unique approval from the Food and Drug Administration (FDA), health care providers and consumers are now learning a fact too long a secret: oral contraceptives in particular dosages can provide emergency postcoital contraception.
Quorum-sensing signals and quorum-sensing genes in Burkholderia vietnamiensis.

Acyl-homoserine lactone (acyl-HSL) quorum sensing is common to many Proteobacteria including a clinical isolate of Burkholderia cepacia. The B. cepacia isolate produces low levels of octanoyl-HSL. We have examined an environmental isolate of Burkholderia vietnamiensis. This isolate produced several acyl-HSLs. The most abundant species was decanoyl-HSL. Decanoyl-HSL in B. vietnamiensis cultures reached concentrations in excess of 20 μM. We isolated a B. vietnamiensis DNA fragment containing a gene for the synthesis of decanoyl-HSL (bviI) and an open reading frame that codes for a putative signal receptor (bviR). A B. vietnamiensis bviI mutant did not produce detectable levels of decanoyl-HSL.
Unilateral delegation and reimbursement systems in an environmental conflict

How unilateral delegation by a citizens’ group with lower ability than a firm affects individual and total effort and the contest favourite under the two reimbursement systems are examined. A citizens’ group that unilaterally hires a delegate to represent them causes the firm to increase its effort level so that it always exceeds the group's delegate – irrespective of the relative strength of the two parties. In contrast to earlier work without either delegation or reimbursement, a citizens’ group that hires a delegate could now be the contest favourite; although it is more likely to occur under the asymmetric reimbursement rule.
The fine structure of the gregarine Pyxinoides balani parasitic in the barnacle Balanus tintinnabulum.

SYNOPSIS. The fine structure of the eugregarine Pyxinoides balani was studied and compared with that of other gregarines previously examined with the electron microscope. P. balani contains cell organelles comparable to those in the archigregarine Selenidium hollandei. These include mitochondria, Golgi complexes, granular and agranular endoplasmic reticulum, membrane-limited granules, vacuoles and myonemes. A comparison of the distribution and fine structure of these organelles with those of the above archigregarine was made. The possible function of the Golgi complex in assisting in producing the transverse septum is suggested. The surface of P. balani is composed of a surface-membrane complex different from that of S. hollandei, and similar to those of the eugregarines previously studied. The complex is composed of an outer plasmalemma, subjacent pentalaminar layer, and underlying, homogeneous, electron-dense layer. The pentalaminar layer is 140–170 A thick and has a structure reminiscent of fused cell membranes seen in tight junctions, myelin figures and nerve myelin. The pentalaminar layer is derived from subsurface cisternae found in sporozoites. The underlying, homogeneous, electron-dense layer is 450–500 A thick. Pores and caveolae are found as specializations of the pentalaminar and homogeneous electron-dense layers. Endoplasmic reticulum is closely associated with the caveolae. The location of the pentalaminar layer at the surface and the presence of pores and caveolae in its structure suggests some transport and/or segregation function.
Malnutrition-induced macrophage apoptosis

Abstract Background. Human and murine studies suggest protein-calorie malnutrition (PCM) results in significant host immunosuppression resulting in increased morbidity and mortality. Apoptosis has been implicated as an important mediator in the immunosuppression observed in several disease states. This study was designed to characterize macrophage apoptosis in a murine model of PCM and investigate components that regulate the apoptotic process, such as protein kinase C (PKC) and Bcl-2 activity. Methods. Swiss-Webster mice (n = 50) were randomly assigned to receive either a control (24% protein) or a PCM diet (0% protein) for 7 days. Peritoneal macrophages were harvested and detection of apoptosis was performed by terminal deoxy-transferase-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) and propidium iodide DNA staining under baseline and pro-apoptotic conditions. Pro-apoptotic conditions included cells treated with tumor necrosis factor-α (TNF-α) (10 ng/mL), interferon-γ (IFN-γ) (50 μ/mL), and a combination of both agents. In addition, levels of PKC activity and expression of Bcl-2 and p53 protein were measured. Results. Peritoneal macrophages from PCM mice had a significantly greater amount of apoptosis at baseline and under stimulated conditions compared with controls. Levels of PCM apoptosis were elevated at baseline by TUNEL staining compared with macrophages from the control group (16.5% ± 1.4%, versus 4.5% ± 1.1%, P P P P P Conclusions. Thus, peritoneal macrophages from PCM mice exhibit significantly greater levels of apoptosis at baseline and when stimulated with pro-apoptotic agents compared with controls. The propensity of macrophages from PCM mice to undergo apoptosis may be attributable in part to decreased PKC activity and Bcl-2 protein expression. These findings may help to explain the associated immune dysfunction observed in malnutrition. (Surgery 2001;129:617-25.)
Craft Specialization, Gender, and Personhood among the Postconquest Maya of Yucatan, Mexico

The early ethnohistoric sources from Yucatan contain a wealth of information concerning Maya artisans, their craft activities, and the special goods they produced. We examine the principal sources for information on the sexual division of labor, engendered craft activities, and the influence of crafts and related domestic arts on Maya perceptions of self. Lexical data from the dictionary sources demonstrate a clear gender complementarity in the organization of work and craft activities. Detailed observations of native practices by early Spanish clerics further suggest that mastery of the basic domestic arts was critical in Maya self perceptions of full personhood.
Do predictions of visual perception aid design

Understanding and exploiting the abilities of the human visual system is an important part of the design of usable user interfaces and information visualizations. Designers traditionally learn qualitative rules of thumb for how to enable quick, easy, and veridical perception of their design. More recently, work in human and computer vision has produced more quantitative models of human perception, which take as input arbitrary, complex images of a design. In this article, we ask whether models of perception aid the design process, using our tool DesignEye as a working example of a perceptual tool incorporating such models. Through a series of interactions with designers and design teams, we find that the models can help, but in somewhat unexpected ways. DesignEye was capable of facilitating A/B comparisons between designs, and judgments about the quality of a design. However, overall “goodness” values were not very useful, showed signs of interfering with a natural process of trading off perceptual vs. other design issues, and would likely interfere with acceptance of a perceptual tool by professional designers. Perhaps most surprisingly, DesignEye, by providing in essence a simple visualization of the design, seemed to facilitate communication about not only perceptual aspects of design, but also about design goals and how to achieve those goals. We discuss resulting design principles for making perceptual tools useful in general.
Classroom Community Building as Framework and Practice in an Elementary Humanities Methods Class: An Instructor's Reflections.

Abstract A team of humanities methods instructors framed their course within the concept of classroom community building to address issues relevant to preservice teachers in areas such as moral commitment, professionalism, caring, and concern. Through activities, lessons, a classroom community analysis paper, and oral and written responses, preservice teachers were asked to address the question, “How can we teach humanities in our classrooms to help students develop a sense of classroom and global community?” This article discusses how classroom community building became a course framework, provides examples of how a community was built and the strengths and limitations of that choice, and closes with insights for teacher educators who may wish to use a similar approach.
Localization of the proenzyme form of the vitellin-processing protease in Blattella germanica by affinity-purified antibodies.

During Blattella germanica embryo development, the nutritive yolk protein vitellin is processed by a cysteine protease, which is activated proteolytically from a proprotease during acidification of yolk granules. A murine polyclonal antiserum was generated with the purified proprotease as the immunogen. The antiserum was made monospecific to proprotease by subtractive affinity chromatography using proprotease-free yolk proteins as ligand. The purified antibodies were employed to investigate the temporal and spatial expression of the proprotease during vitellogenesis and embryo development. Anti-proprotease-reactive peptides appeared in extracts of fat bodies and ovarian follicles of post-mating females, but not in fat bodies of males or the fat bodies or follicles of unmated females, suggesting that the proprotease is synthesized extraovarially. Use of the antibodies was extended to monitor the kinetics of proprotease disappearance during early embryo development. Arch. Insect Biochem. Physiol. 38:109–118, 1998. © 1998 Wiley-Liss, Inc.
A Natural Toxic Defense System: Cardenolides in Butterflies versus Birdsa

We have verified that wild birds can become conditioned to reject naturally toxic insects either visually (experiment 1) or by taste (experiment 2). We have also verified, however, that unconditioned taste rejection of noxious chemicals by wild birds also occurs (experiment 3). Such unconditioned responses to the aposematic visual and taste cues of many insects, in fact, often appear to be as important as, or more important than, conditioned responses. In a large number of laboratory feeding experiments with wild birds as predators of aposematic insects, initial and/or long-term rejection occurs without prior laboratory conditioning experience. Although in some experiments the birds may have previously been exposed to (and therefore perhaps conditioned by) the aposematic prey in the wild, other experiments have used naive birds or insects whose ranges do not overlap those of the birds. Wiklund and Jarvi, for example, tested the response of 47 naive hand-raised birds of four species to five aposematic insect species, and found that 69/136 (51%) insects were rejected visually without even tasting, while 63 were tasted and then rejected. Only four of the insects were actually ingested. Similarly, in Bowers' study of the response of Massachusetts blue jays to aposematic western U.S. Euphydryas butterflies, several blue jays consistently rejected the butterflies visually or by taste without having eaten any. While these studies were not designed to separate neophobic effects from innate visual and/or taste aversions, they do differentiate between conditioned and unconditioned responses. Since both conditioned and unconditioned rejections can be demonstrated in the lab by insectivorous birds, and our available field evidence does not yet let us distinguish the mechanisms behind the observed patterns, our initial question, of the relative importance of conditioned versus unconditioned rejection mechanisms in different natural situations, is not yet answerable. The most important requirement of a food-rejection strategy is that it prevents both poisoning and starvation. We have shown, however, that rejection of a noxious insect by a bird can take place at four distinct levels (visual, non-destructive taste sampling, destructive taste sampling, or post-ingestional physiological rejection), the first three of which may be either unconditioned or conditioned by a physiological reaction to ingestion.(ABSTRACT TRUNCATED AT 400 WORDS)
Mediation of mouse natural cytotoxic activity by tumour necrosis factor.

Natural cell-mediated cytotoxic activity in the mouse has been associated with two types of effector cells, the natural killer (NK) cell and the natural cytotoxic (NC) cell, which seem to differ with regard to their patterns of target selectivity, cell surface characteristics and susceptibility to regulatory factors1. During studies on the mechanism of action of cytotoxic molecules, it became evident that WEHI-164, the prototype NC target cell, was highly susceptible to direct lysis by both human and mouse recombinant tumour necrosis factor (TNF). Here we show that NC, but not NK activity mediated by normal splenocytes, is abrogated by rabbit antibodies to recombinant and natural TNF, respectively. Thus, the cell-mediated activity defined as NC is due to release of TNF by normal spleen cells and does not represent a unique natural effector mechanism.
Overlap elimination in floorplans

Describes an algorithm for eliminating/reducing overlaps among blocks (macros) in VLSI chip floorplans. These blocks are assumed to be rectangular and can be either preplaced or movable. A movable block can have a fixed or a flexible shape. The authors describe applications for such an algorithm in the floorplanning process. The approach discussed in the paper is targeted towards macro cell based sea-of-gates designs. >
Topological tradeoffs in autocatalytic metabolic pathways

Metabolic pathways in cells convert external food and resources into useful cell components and energy. In many cases the cell employs product inhibition to regulate and control these pathways. We investigate the performance of such regulation and control on certain autocatalytic pathways. Specifically, we examine how well the pathways can maintain the desired output concentrations in the presence of disturbances, such as perturbations in resources, enzyme concentrations and product demand. Using control theoretic tools, we show the effects of the pathway size, the reversibility of the intermediate reactions and the coupling of pathways through the consumption of intermediate metabolites on performance. In addition, we establish some necessary conditions on the existence of fixed points and their stability for such pathways.
Ultra long-range interactions between silicon surfaces

Abstract This paper takes a new look at interactions between hydroxylated silicon surfaces, which are commonly exploited in wafer bonding. In the past, strong connections have been made between the fracture toughness associated with such interactions. Here, we go one step further to examine the strength and range of the interactions, as well as the fracture energy from the perspective of traction-separation relations and cohesive zone modeling. The surface profiles of the interacting surfaces along with the initially bonded state were characterized by interferometry. The bonded silicon strips were separated by wedge loading while the separation of the surfaces was measured by infra-red crack opening interferometry. This data was used in conjunction with J-integral concepts to extract traction-separation relations directly. Variations in the fracture energy and strength and range of the interactions of a range of samples were linked to the mismatch in the waviness of the contact pairs and the amount of damage this caused. Finally, the strength and range of the interactions of well-bonded samples appeared to be linked to DLVO and capillary effects rather than van der Waals interactions.
The changing indications for excretory urography

EXCRETORY urography (EU) is considered the first and foremost radiological procedure in the evaluation of the urinary tract. However, with experience and the emergence of newer imaging modalities, the role of EU needs reevaluation in the diagnostic studies of patients in many clinical situations. Numerous reports have appeared in the literature detailing the low yield of EU in certain clinical settings. Despite repeated condemnation of routine EU in conditions where its role is questionable, no decrease in the overall numbers of this procedure has been observed; teaching hospitals may be an exception. Approximately 4 million excretory urograms are performed in this country every year, with a total cost of over a half billion dollars. 1 Most of these examinations are accomplished in physicians' offices and nonteaching hospitals. Whether excretory urograms really are indicated in so large a group of patients is questionable and controversial. Escalating medical costs make it imperative
Ciprofloxacin Resistance in Campylobacter jejuni Evolves Rapidly in Chickens Treated with Fluoroquinolones

Fluoroquinolones are commonly used to treat gastroenteritis caused by Campylobacter species. Domestically acquired fluoroquinolone-resistant Campylobacter infection has been documented recently in the United States. It has been proposed that the increase in resistance is due, in part, to the use of fluoroquinolones in poultry. In separate experiments, the effects of sarafloxacin and enrofloxacin treatment of Campylobacter jejuni–infected chickens on the development of ciprofloxacin resistance were measured. Fecal samples were collected before and after treatment and were cultured for C. jejuni. When enrofloxacin or sarafloxacin was used at US Food and Drug Administration‐ approved doses in broiler chickens, resistance developed rapidly and persisted in C. jejuni. MICs of ciprofloxacin increased from a base of 0.25 mg/mL to 32 mg/mL within the 5-day treatment time frame. These results show that the use of these drugs in chickens rapidly selects for resistant Campylobacter organisms and may result in less effective fluoroquinolone therapy for cases of human campylobacteriosis acquired from exposure to contaminated chicken. Campylobacter jejuni is recognized as the leading cause of bacterial gastroenteritis in the United States, accounting for 2.4 million cases each year [1]. Epidemiologic investigations of sporadic cases have indicated that chicken is the most common source of human infection [2, 3]. In addition, survey data show that Campylobacter species contaminate80% of retail chicken meats [4]. Campylobacter infection causes acute inflammatory enteritis that may be indistinguishable from that caused by Salmonella infection. Although Campylobacter enteritis is usually a selflimiting diarrheal disease, infrequent cases of serious invasive or relapsing illness, particularly in immunocompromised patients, may require antibiotic therapy. When antimicrobials are used to treat adults with enteritis, they are most effective in limiting the duration of illness when given early in the course of infection, before the etiologic agent is confirmed by culture [5]. Because fluoroquinolones are commonly used to treat persons with Campylobacter infections, the emergence of resistant strains will limit the therapeutic usefulness of these drugs. The fluoroquinolones sarafloxacin and enrofloxacin were licensed in 1995 and 1996, respectively, for controlling mortality associated with Escherichia coli infections in chickens. Both antimicrobials are administered to the entire chicken house ad libitum in water for up to 5 days for sarafloxacin and for 5‐ 7 days for enrofloxacin. Surveillance data suggest a temporal association between the approval of these drugs in poultry and increased resistance in Campylobacter isolates from human infections [6, 3]. To measure the impact of fluoroquinolone use in chickens on resistance development in C. jejuni, experimentally infected animals were medicated with sarafloxacin or enrofloxacin. C. jejuni isolates were collected over time, and fluoroquinolone MICs were measured.
On the origin of the Galápagos hawk: an examination of phenotypic differentiation and mitochondrial paraphyly

Previous phylogenetic hypotheses suggest a sister group relationship between mainland and widespread Buteo swainsoni (Swainson’s hawk) and the island archipelago taxon Buteo galapagoensis (Galapagos hawk). We further describe phylogenetic relationships of this clade using molecular data from the mitochondrial control region, and consider the role of niche expansion on phenotype using morphological data from B. galapagoensis, B. swainsoni, and related Buteo jamaicensis (red-tailed hawk). Among 52 unique Buteo haplotypes, phylogenetic analyses support a monophyletic B. galapagoensis clade within a clade of B. swainsoni haplotypes, rendering B. swainsoni paraphyletic with respect to B. galapagoensis. Mitochondrial paraphyly is likely a result of incomplete lineage sorting subsequent to a recent colonization event and exemplifies speciation of peripheral population isolates. Morphological comparisons indicate that metrics associated with prey capture differ significantly between B. galapagoensis and B. swainsoni, but are similar between B. galapagoensis and B. jamaicensis. These results suggest directional selection on B. galapagoensis morphology associated with feeding, possibly an outcome of decreased interspecific competition and change towards a more generalist diet shared by B. jamaicensis. In the B. galapagoensis lineage, our results suggest that genetic drift influences the neutral mitochondrial marker, whereas selection may have driven phenotypic character change. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95, 779‐789.
FastQuery: A Parallel Indexing System for Scientific Data

Modern scientific datasets present numerous data management and analysis challenges. State-of-the-art index and query technologies such as FastBit can significantly improve accesses to these datasets by augmenting the user data with indexes and other secondary information. However, a challenge is that the indexes assume the relational data model but the scientific data generally follows the array data model. To match the two data models, we design a generic mapping mechanism and implement an efficient input and output interface for reading and writing the data and their corresponding indexes. To take advantage of the emerging many-core architectures, we also develop a parallel strategy for indexing using threading technology. This approach complements our on-going MPI-based parallelization efforts. We demonstrate the flexibility of our software by applying it to two of the most commonly used scientific data formats, HDF5 and NetCDF. We present two case studies using data from a particle accelerator model and a global climate model. We also conducted a detailed performance study using these scientific datasets. The results show that FastQuery speeds up the query time by a factor of 2.5x to 50x, and it reduces the indexing time by a factor of 16 on 24 cores.
Percutaneous reduction and fixation of an intra-articular calcaneal fracture using an inflatable bone tamp: description of a novel and safe technique

Calcaneal fractures are common injuries involving the hind foot and often a source of significant long-term morbidity. Treatment options have changed throughout the ages from periods of preferred nonoperative management to closed reduction with a mallet, and more recently, open reduction and anatomic internal fixation. The current treatment of choice; however, is often debated, as open management of these fractures carries many risks to include wound breakdown and infection. A less invasive form of surgical management through small incisions, while maintaining the ability to obtain joint congruency, anatomic alignment, and restore calcaneal height and width would be ideal. We propose a novel form of fracture reduction using an inflatable bone tamp and percutaneous fracture fixation. Preoperative planning and experienced fluoroscopy is crucial to successful management using this method. Although we achieved successful radiographic outcome in this case, long-term functional outcome of this technique are yet to be published.
Chemical Method for the Determination of Starch in Polyethylene

Abstract A chemical/spectrophotometric procedure has been developed that allows the determination of starch and some modified starches (as glucosyl residues) in polyethylene films and pellets. The method uses samples containing up to 60 mg polyethylene and determines the anhydrous starch content of samples possessing starch loads in the range typically encountered with degradable plastics (5–40%). The method consists of dissolution of the polyethylene component into decahydronapthalene (decalin) at 150[ddot]C followed by solubilization with partial hydrolysis of the starch component in 1M HCl at 100[ddot]C. An aliquot of the resulting starch hydrolyzate is analyzed for total carbohydrate using the phenol-sulfuric acid method. The method has been tested on two sets of specially prepared starch-polyethylene films as well as on several commercial products.
Identifying and Solving Impediments to the Social and Counseling Psychology Interface

After 30 years of scholarship, experts on the interface of counseling and social psychology are raising serious and important questions regarding its scientific and practical effectiveness and its future. Written by psychologists actively researching at the interface, this group of articles provides a conceptualization of the interface, employs that conceptualization to identify and understand impediments to effective collaboration, and proposes solutions.
Antihyperalgesic effect of tetrodotoxin in rat models of persistent muscle pain.

Persistent muscle pain is a common and disabling symptom for which available treatments have limited efficacy. Since tetrodotoxin (TTX) displays a marked antinociceptive effect in models of persistent cutaneous pain, we tested its local antinociceptive effect in rat models of muscle pain induced by inflammation, ergonomic injury and chemotherapy-induced neuropathy. While local injection of TTX (0.03-1 μg) into the gastrocnemius muscle did not affect the mechanical nociceptive threshold in naive rats, exposure to the inflammogen carrageenan produced a marked muscle mechanical hyperalgesia, which was dose-dependently inhibited by TTX. This antihyperalgesic effect was still significant at 24h. TTX also displayed a robust antinociceptive effect on eccentric exercise-induced mechanical hyperalgesia in the gastrocnemius muscle, a model of ergonomic pain. Finally, TTX produced a small but significant inhibition of neuropathic muscle pain induced by systemic administration of the cancer chemotherapeutic agent oxaliplatin. These results indicate that TTX-sensitive sodium currents in nociceptors play a central role in diverse states of skeletal muscle nociceptive sensitization, supporting the suggestion that therapeutic interventions based on TTX may prove useful in the treatment of muscle pain.
9‐Fluorenylmethyl 1‐Benzotriazolyl Carbonate (3‐Oxy‐benzotriazolinium‐1‐carboxylic Acid 9H‐Fluoren‐9‐ylmethyl Ester)

[82911-71-5] C21H15N3O3 (MW 357.4) InChI = 1S/C21H15N3O3/c25-21(27-24-20-12-6-5-11-19(20)22-23-24)26-13-18-16-9-3-1-7-14(16)15-8-2-4-10-17(15)18/h1-12,18H,13H2 InChIKey = KNSPZTVPSAKHBN-UHFFFAOYSA-N (reagent for the preparation of 9-fluorenylmethoxycarbonyl (Fmoc) derivatives of amines and amino acids) Alternate Name: 3-oxy-benzotriazolinium-1-carboxylic acid 9H-fluoren-9-ylmethyl ester; benzotriazol-1-yl-9-fluorenylmethyl carbonate; Fmoc-OBt. Physical Data: white solid; mp 180 °C.1 Solubility: soluble in common organic solvents (i.e., diethyl ether, THF, and CH2Cl2). Form Supplied in: solid. Analysis of Reagent Purity: melting point. Preparative Methods: it can be prepared from 9-fluorenylmethyl chloroformate and dicyclohexylammonium salt of 1-hydroxybenzotriazole. This protocol provided the product in 83% yield.1 Purification: recrystallization from chloroform–ether.1 Handling, Storage, and Precautions: irritating to eyes, respiratory system, and skin. Stored at 2–8 °C.