cssi/SciSciGPT-SciSciNet huggingface dataset:
Expertise as mental set: The effects of domain knowledge in creative problem solving

Experts generally solve problems in their fields more effectively than novices because their wellstructured, easily activated knowledge allows for efficient search of a solution space. But what happens when a problem requires a broad search for a solution? One concern is that subjects with a large amount of domain knowledge may actually be at a disadvantage, because their knowledge may confine them to an area of the search space in which the solution does not reside. In other words, domain knowledge may act as a mental set, promoting fixation in creative problem-solving attempts. A series of three experiments in which an adapted version of Mednick’s (1962) remote associates task was used demonstrates conditions under which domain knowledge may inhibit creative problem solving.
An electrodynamic model of the solar wind interaction with the ionospheres of Mars and Venus

The electrodynamic model for the solar wind interaction with nonmagnetic planets modified to include the effects of nonohmic currents in the upper ionosphere is examined. The model is used to calculate convection patterns induced by the solar wind in the ionospheres of Mars and Venus, with the observations of the neutral mass spectrometer of Vikings 1 and 2 providing the neutral atmosphere for Mars. Model calculations reproduced the retarding potential analyzer data and indicate that the ionosphere above 200 km is probably controlled by convection rather than chemistry or diffusion. The resulting model calculations were compared to radio occultation data from Mariners 5 and 10 and Venera 9 which represent extremes in the variability of the upper Cytherean ionosphere, and the calculations fell within this variation.
Non-Muffin-Tin Energy Bands for Silicon by the Korringa-Kohn-Rostoker Method

A method is proposed for removing the "muffin-tin" restriction from the Green's function or the Korringa-Kohn-Rostoker method of band calculation and, more generally, from multiple-scattering theory as formulated by Beeby and Edwards. The method is applied to a model for crystalline silicon involving a single parameter which is adjusted to reproduce the experimental indirect gap. The numerical results are in good agreement with a large number of experiments and in particular support the view that the $\ensuremath{\Delta}$ axis is important to the reflectivity peak at 3.4 eV. (The energy separation ${\ensuremath{\Gamma}}_{15}\ensuremath{-}{{\ensuremath{\Gamma}}_{25}}^{\ensuremath{'}}$ is found to be 3.04 eV.)
Comment on "A new proposal for the ground state of the FeO- cluster in the gas phase and for the assignment of its photoelectron spectra".

In “A New Proposal for the Ground State of the FeOCluster ...” by Hendrickx and Anam,1 the authors attempt to interpret the photoelectron spectrum of FeOby proposing that the ground state of FeOis not a 4∆ state, the currently accepted assignment, but instead is a 6Σ+ state. The photoelectron spectrum2,3 of FeOis complex, given that the ground electronic state of neutral FeO is a 5∆ state.4 However, the proposed reassignment of the anion ground state is clearly incorrect and appears to be based on an incomplete and highly selective reading of the experimental data on this system. The key issues are summarized below. First, this proposed assignment cannot be reconciled with the very high resolution (∼0.001 cm-1) autodetachment spectrum of FeOreported by Andersen et al.5 This paper, which was inexplicably not referenced by Hendrickx, presents fully rotationally resolved electronic spectra of FeOthat originate from a ground state with the spin-orbit fine structure characteristic of a 4∆ state; specifically, bands originating from the Ω ) 7/2, 5/2, and 3/2 spin-orbit components with an average spacing of 233 cm-1 were identified. None of this fine structure would have been seen from a 6Σ+ state, which should be a Hund’s case (b) molecule with no spin-orbit splitting. Moreover, the experimental rotational constant of 0.4972 cm-1 for the Ω ) 7/2 multiplet yields a bond length of 1.641 A, in good agreement with the bond length of 1.635 A calculated by Hendrickx for the 4∆ state of FeO-, but in poorer agreement with the bond length of 1.683 A calculated for the 6Σ+ state. Second, the zero-electron-kinetic-energy (ZEKE) spectrum of FeOmeasured by Drechsler et al.,6 which was referenced by Hendrickx, exhibits partial rotational resolution on the origin band that was indeed fit very well using the rotational constants from Andersen et al., with an overall band contour consistent with detachment from a 4∆ anion state. In addition, the ZEKE spectrum exhibited spin-orbit fine structure that was shown to be fully consistent with the 4∆ spin-orbit splittings of Andersen et al. Neither the rotational structure nor fine structure in the ZEKE spectrum is consistent with a 6Σ+ ground state for the anion. Finally, we concur with Hendrickx and Anam that the photoelectron spectrum of FeOis not fully understood. At low electron binding energy, it is dominated by transitions to the 5∆ ground state of FeO but also exhibits minor transitions that have been tentatively assigned6 to an excited 7Σ+ excited state of FeO. This state is not accessible by one-electron detachment from the anion 4∆ state. However, while the 7Σ+ state is accessible by one-electron detachment from the proposed anion 6Σ+ ground state, the 5∆ state, which is responsible for most of the transitions in this region, is not (as pointed out by Hendrickx). Thus, even leaving out the issues considered in the preceding paragraphs, the proposed reassignment of the FeOground state is perplexing, as it appears to cause more problems than it solves.
Mechanical Design and Vibro-Acoustic Testing of Ultrathin Carbon Foils for a Spacecraft Instrument

IBEX-Hi is an electrostatic analyzer spacecraft instrument designed to measure the energy and flux distribution of energetic neutral atoms (ENAs) emanating from the interaction zone between the Earth’s solar system and the Milky Way galaxy. A key element to this electro-optic instrument is an array of fourteen carbon foils that are used to ionize the ENAs. The foils are comprised of an ultrathin (50–100A thick) layer of carbon suspended across the surface of an electroformed Nickel wire screen, which in turn is held taught by a metal frame holder. The electroformed orthogonal screen has square wire elements, 12.7 μm thick, with a pitch of 131.1 wires/cm. Each foil holder has an open aperture approximately 5 cm by 2.5 cm. Designing and implementing foil holders with such a large surface area has not been attempted for spaceflight in the past and has proven to be extremely challenging. The delicate carbon foils are subject to fatigue failure from the large acoustic and vibration loads that they will be exposed to during launch of the spacecraft. This paper describes the evolution of the foil holder design from previous space instrument applications to a flight-like IBEX-Hi prototype. Vibro-acoustic qualification tests of the IBEX-Hi prototype instrument and the resulting failure of several foils are summarized. This is followed by a discussion of iterative foil holder design modifications and laser vibrometer modal testing to support future fatigue failure analyses. The results of these activities indicate that there is no strong dependency of the natural frequencies or transmissibilities of the foils on the different foil holder and screen configurations. However, for all foil holder designs, the natural frequencies of the foils were observed to decrease noticeably from exposure to acoustic testing. These test results, when combined with foil holder assembly considerations, suggest that the welded frame and integrated screen designs should be incorporated into the architecture of the IBEX-Hi flight instrument.Copyright © 2009 by ASME
A Flipped First-Year Digital Circuits Course for Engineering and Technology Students

This paper describes a flipped and improved first-year digital circuits (DC) course that incorporates several active learning strategies. With the primary objective of increasing student interest and learning, an integrated instructional design framework is proposed to provide first-year engineering and technology students with practical knowledge of DC. The research presented here compares the effectiveness of the flipped course to the previous traditional course through a controlled experimental study. The improved effectiveness of the flipped course is confirmed through the significant increase in course content and significant improvements in students' performance and their perceptions of their learning experience. Preliminary results suggest that students' academic success, and their engagement and interest in engineering, can be enhanced by refinement of an integrated instructional design framework. The authors believe that this positive outcome is a result of alignment of online preview of lectures, face-to-face student/instructor and peer interactions, discussions, hands-on activities, combined with several active learning strategies infused into the class.
Derivatives of 5-deoxy-5-seleno-d-xylose

Abstract The synthesis of derivatives of 5-deoxy-5-seleno- d -xylose is described. These anhydro derivatives represent a new class of carbohydrates in which the usual anhydro oxygen is replaced by selenium.
Effects of lubricants on the second fusion behavior of rigid polyvinyl chloride

Rigid polyvinyl chloride (RPVC) is thermally unstable and difficult to process. The processibility of RPVC compounds markedly depends on the type and level of lubricants present. Lubricants are compounded into RPVC powder and the resulting dry blend is either directly converted into the final product requiring the resin to fuse only once, or pelletized first followed by conversion into the final product in a subsequent operation requiring the resin to fuse twice. The effects of lubricants on the first fusion have been well studied but little is known about the second fusion. We studied the effects of eleven common lubricants on the second fusion of a RPVC master, batch at three levels of concentration at several temperatures., The lubricants were compunded with the RPVC powder, the dry blends molded into one-inch cube samples, and the molded samples fused under shearing conditions comparable to the actual processing. We found that the effects of the lubricants on the second fusion were generally the same as those on the first fusion. Apparently, the properties of the lubricants and their interactions with the RPVC resin are not altered by the first fusion history.
Quantile contours and multivariate density estimation for massive datasets via sequential convex hull peeling

We propose a low-storage, single-pass, sequential method for the execution of convex hull peeling for massive datasets. The method is shown to vastly reduce the computation time required for the existing convex hull peeling algorithm from O(n 2) to O(n). Furthermore, the proposed method has significantly smaller storage requirements compared to the existing method. We present algorithms for low-storage, sequential computation of both the convex hull peeling multivariate median and the convex hull peeling pth depth contour, where 0 < p < 1. We demonstrate the accuracy and reduced computation time required of the proposed method by comparing to the existing convex hull peeling method through simulation studies.
The response of white spruce (Picea glauca (Moench) Voss) shoot apices to exposures of chronic gamma radiation

Abstract Four-year-old trees of white spruce ( Picea glauca (Moench) Voss) were exposed to chronic gamma irradiation at exposures ranging from 0·5 to 30·0 R/20-hr day for one growing season. The LD 50 for shoot growth was about 28 R/20-hr day. The apical initials were the first cells to show radiation damage. The central mother cell zone was the next most sensitive region. Needle primordia formation decreased with increased exposure rates, with an LD 50 of 2·0 R/20-hr day. The controls appeared to indicate that volume of the central mother cell zone was related to production of needle primordia, but this was disproved in the treated material when needles were produced in apices having no central mother cell zone.
Laparoscopic choledochoscopy and extraction of common bile duct stones

Various strategies have been proposed for the treatment of common bile duct stones encountered during laparoscopic cholecystectomy (LC). Eighty-three patients who had choledocholithiasis discovered during or just prior to LC are included in this study. These patients were treated by various modalities including preoperative, intraoperative, and postoperative endoscopic retrograde cholangiopancreatography and sphincterotomy, laparoscopic choledochotomy, transcystic duct-common bile duct (TCD-CBD) exploration, and conventional “open” common duct exploration. Sixty-six patients were successfully treated with TCD-CBD exploration. They were discharged on average 2.6 days postoperatively and were able to return to normal physical activities within 7 days of discharge. There was minimal morbidity and no mortality. The technique of TCD-CBD exploration is described in detail. The role of laparoscopic choledochotomy and endoscopic sphincterotomy for management of common duct stones in patients undergoing laparoscopic cholecystectomy appears limited.
Commissural projection to the dentate gyrus of the rat: evidence for feed-forward inhibition

We studied the response properties of interneurons of the dentate gyrus to stimulation of the commissural and perforant path inputs in urethane-anesthetized rats. Commissural stimulation inhibited the population spike evoked by concurrent stimulation of the perforant path. Stimulation thresholds of the interneurons were significantly lower than thresholds of the projection cells. The latency of 3 interneurons was shorter than the onset of the commissurally evoked field response. The results suggest that commissural fibers directly excite interneurons of the dentate gyrus, and the activity of the projection cells may be inhibited in a feed-forward manner.
Environmental and chemical degradation of carbon/epoxy lap joints for aerospace applications, and effects on their mechanical performance

Composite structures in service are typically subjected to different environmental conditions, which may affect their mechanical performance as well as their flammability potential. This study investigates the degradation encountered by lap joints made with woven carbon/epoxy and epoxy-based adhesive, treated in water or anti-icing additive or jet fuel or hydraulic fluid. Gravimetric tests were carried out, and degradation was observed with changes in color, mass, microscopic features and mechanical properties, with the support of statistics. This investigation proves that the performance of the epoxy-based structural adhesive deteriorates considerably when the adhesive is contaminated by hydraulic fluid and anti-icing additive, while the carbon/epoxy weave appears affected by anti-icing additive at a lesser rate.
Health impact assessment: A comparison of 45 local, national, and international guidelines

Abstract This article provides a comparison of health impact assessment (HIA) guidelines from around the world and for multiple geographic scales. We identify commonalities and differences within HIA guides to discuss the plausibility of consensus guidelines and to inform guideline development. The practice of HIA has grown over the last two decades with a concurrent growth of HIA guides. This study expands on earlier review work and includes guides published since 2007 (Mindell, Boltong and Forde, 2008). From April 2010 to October 2011, 45 HIA guides were identified through an internet search and review of previous research. Common characteristics, key features, and the HIA process were analyzed. The 45 documents recommended similar but not identical processes for conducting HIAs. These analyses suggest that guidelines for HIAs are similar in many areas of the world and that new HIA practitioners can use these findings to inform their approach. Further discussion is needed to determine if the approaches established in these guidelines are followed and if one set of common guidelines could be written for use in numerous countries and regions.
Optimal causal control of a wave energy converter in a random sea

Abstract This paper concerns the design of feedback control systems to maximize power generation of a wave energy converter (WEC) in a random sea. In the literature on WEC control, most of the proposed feedback controllers fall into three categories. Many are static; i.e., they extract power by imposing an equivalent damping or resistive load on the power take-off (PTO) devices. Others are dynamic and are designed to maximize power generation at all frequencies, which results in an anticausal feedback law. Other dynamic control design methods are causal, and are tuned to achieve the anticausal performance at only a single frequency. By contrast, this paper illustrates that the determination of the true optimal causal dynamic controller for a WEC can be found as the solution to a nonstandard linear quadratic Gaussian (LQG) optimal control problem. The theory assumes that the control system must make power generation decisions based only on present and past measurements of the generator voltages and/or velocities. It is shown that unlike optimal anticausal control, optimal causal control requires knowledge of the stationary spectral characteristics of the random sea state. Additionally, it is shown that the efficiency of the generator factors into the feedback synthesis. The theory is illustrated on a linear dynamical model for a buoy-type WEC with significant resonant modes in surge and pitch, and equipped with three spatially-distributed generators.
In-Hospital Cardiopulmonary Resuscitation

To the Editor.— Although our article 1 was cited by all four authors who discussed do-not-resuscitate (DNR) orders in a recent issue of JAMA , 2-5 a critical distinction was missed that might have clarified the apparent disagreement between Murphy 2 and Youngner. 3 The former called for unilateral DNR decisions by the physician when resuscitation is demonstrably futile; the latter accused the former of unacceptable paternalism in excluding patient or family participation in DNR discussions. The distinction missing from this debate is that between the physician's decision whether resuscitation should be offered and the decision whether resuscitation should be discussed. As we explained in our article, when resuscitation is futile and offers nothing of benefit to the patient, it need not be offered as a matter of choice since it serves neither the patient's interests nor his rights. In this case, the decision against resuscitation is a matter of the
Maintenance lysine requirement and efficiency of using lysine for accretion of whole-body lysine and protein in young chicks

Two bioassays were conducted to determine the maintenance requirement and efficiency of utilization of dietary Lys in young chicks. New Hampshire x Columbian males were used in Assay 1 and Avian x Avian males were used in Assay 2. In each assay, chicks were given free access for 10 d to crystalline amino acid (AA) diets containing graded levels of L-Lys.HCl. Doses of Lys represented 5, 40, 55, 70, and 95% of its ideal level in Assay 1; all other AA were set at 100% of their ideal levels, except for the lowest Lys level, in which the other AA were maintained at a 15% excess. In Assay 2, doses of Lys represented 5, 10, 40, 55, 70, and 95% of ideal; all other AA were maintained at minimized excess levels that were 15% (of ideal) above the various doses of Lys. After 24 h of feed deprivation, chicks were killed for whole-body protein and AA analysis. In Assay 1, protein accretion (r2 = 0.95) and Lys accretion (r2 = 0.98) were linear (P < 0.01) functions of Lys intake. Slope of the Lys accretion regression line indicated that 75.8% of the crystalline Lys ingested (above maintenance) was retained. The Lys required for zero protein accretion was 12 mg/d or 45 mg/d per kg3/4, whereas the Lys required for zero Lys accretion was 30.3 mg/d or 114 mg/d per kg3/4. With Avian x Avian chicks, protein accretion (r2 = 0.99) and Lys accretion (r2 = 0.99) were linear (P < 0.01) functions of Lys intake. Slope of the Lys regression line indicated that 79.3% of the Lys ingested was retained. The Lys requirement for zero protein accretion was 2.5 mg/d or 6.9 mg/d per kg3/4. The Lys maintenance requirement for zero Lys accretion, however, was 32.3 mg/d or 89.1 mg/d per kg3/4. The data demonstrated that at nitrogen equilibrium, chicks are in negative Lys balance but are in positive balance of glycine and proline.
Theoretically unlimited bandwidth frequency divider

A new method of synthesiziag a sine wave frequency divider (division by 2) with theoretically unlimited bandwidth is presented.
Detecting Deception: Current Models and Directions

Traditional procedures for detecting deception are based on the global-signs-of-lying model, with its assumption that certain universal, physiologically mediated signs result from attempts to deceive, independent of content. More recent attempts to detect deception can profitably be viewed from a cognitive rather than affective perspective: (a) in terms of accuracy of knowledge, in which a person's success at deception regarding a particular characteristic depends on the extent of his or her knowledge of that characteristic; and (b) in terms of attempts to personalty influence the examiner. Such procedures have been successful in detecting simulation in psychopathology, amnesia, neurological disorders, pain, and other areas. They tend to be situation specific and to depend on empirically discovered differences between simulators and persons who possess the characteristic.
Small Intestinal Disaccharidase Activity and Ileal Villus Height Are Increased in Piglets Consuming Formula Containing Recombinant Human Insulin-Like Growth Factor-I

The effect of orally administered IGF-I on intestinal development was assessed in piglets. Cesarean-derived, colostrum-deprived piglets received formula alone or formula containing 65 nM (500 microg/L) of recombinant human IGF-I. IGF-I intake averaged 200 microg/kg/d. On d 7 and 14 postpartum, piglets were killed, organs were removed and weighed, and tissue and blood samples were collected. The small intestine was divided into 13 segments that were weighed and measured. A sample of each segment was fixed in formalin, and the mucosa was scraped for enzyme analyses. Food intake, body and organ weights, intestinal weight, length, protein, DNA and RNA content did not differ between the treatment groups. Serum IGF-I, IGF-II, and IGF-binding protein profiles and tissue IGF-binding protein mRNA expression were also comparable between the treatment groups. In contrast, intestinal enzymes and villus height were increased by oral IGF-I. Lactase was approximately 2-fold higher (p < or = 0.05) in the jejunum and proximal ileum, and sucrase was approximately 50% higher (p < or = 0.05) in the jejunum of IGF-I-treated animals than in controls. Villus height in the terminal ileum was approximately 50% greater in IGF-I-treated animals than in controls (p = 0.03). In conclusion, orally administered IGF-I at 200 microg/kg did not affect whole body or organ growth or serum IGF-I concentrations; however, intestinal disaccharidase activity and ileal villus growth were responsive to orally administered IGF-I, supporting a potential role for milk-borne IGF-I in neonatal intestinal development.
Energy policy issues in developing countries Lessons from ASEAN's experience

Abstract This paper reviews the energy policy responses of the five countries originally composing the Association of Southeast Nations (ASEAN) — Indonesia, Malaysia, the Philippines, Singapore, and Thailand — following the first price shocks of 1973–1974. It analyses the implications of the demand and supply management policies adopted, especially those related to pricing and diversification. It calls attention to the implications of these policies for structural changes in industries, including the shift away from energy-intensive to labour-intensive technologies; the role that technological change and technology transfer can play; the role of the transport sector in conservation, and the scope for oil-to-coal switching. It raises policy and research questions on the allocative efficiency of demand and supply management policies.
Indicators of scientific manpower

Although the statistics on science and engineering personnel inScience Indicators — 1976 can be used to trace changes in the supply and utilization of these personnel, very little is presented that would allow readers to discern the emergence of strengths or weaknesses in this area. The author suggests that the inclusion of a variety of indicators relating to age, quality and mobility of scientific personnel would be a useful addition to the chapter. Additional indicators of labor market change, such as salaries, would also be helpful for policy purposes.
Underpricing of IPOs that Follow Private Placements

This study addresses the question of the effectiveness of private placements in mitigating the information asymmetry problem faced by IPO firms, and their impacts on issuing costs, both underpricing and underwriting spreads, of IPOs. We examine the underpricing of initial public offerings by firms that made private placements prior to their IPOs (PP IPO firms). We find that PP IPOs experience significantly lower underpricing. They also have smaller offer price revisions following the book building process. Furthermore, PP IPOs are associated with more reputable underwriting syndicates and lower underwriting spreads. These findings persist after we control for known factors that impact underpricing in the regression analysis. We conclude that the results are consistent with the information asymmetry explanation for the global phenomenon of IPO underpricing, and lend support to the notion that prior private placements help reduce information asymmetry, thus resulting in lower issuing costs for IPO firms.
The role of gene O protein in the replication of bacteriophage λ

Abstract The role of the product of gene O of bacteriophage λ in phage DNA replication was examined by shifting cells infected with an Ots mutant to the nonpermissive temperature after incubation at the permissive temperature. Thymidine incorporation after the temperature shift exhibits biphasic kinetics, with rapid synthesis immediately after the shoft and slower synthesis 2–15 min after the shift. Following a shift to the nonpermissive temperature early in infection, the proportion of replicative intermediates decreases substantially and σ-structures are favored for preservation. When the shift is done late in infection, the proportion of replicative intermediates remains the same. The average length of single-stranded regions at the branch points increases after a shift to the nonpermissive temperature. Most of the counts which are incorporated after the temperature shift are incorporated into strands which are longer than unit length. These results favor a model in which λ O protein is required for the initiation of replication, but at least some elongation can continue in the absence of O. It is possible that O protein plays a role in elongation of the lagging strand at replicative forks. This model suggests a way to regulate the transition between θ and σ replication which occurs as λ infection proceeds.
A mobile augmented reality system to enhance live sporting events

Sporting events broadcast on television or through the internet are often supplemented with statistics and background information on each player. This information is typically only available for sporting events followed by a large number of spectators. Here we describe an Android-based augmented reality (AR) tool built on the Tesseract API that can store and provide augmented information about each participant in nearly any sporting event. This AR tool provides for a more engaging spectator experience for viewing professional and amateur events alike. We also describe the preliminary field tests we have conducted, some identified limitations of our approach, and how we plan to address each in future work.
Efficient recursive algorithm for the operational space inertia matrix of branching mechanisms

This article describes an efficient recursive algorithm for the computation of the operational space inertia matrix of an n-link branching robotic mechanism with multiple (m) operational points. Th...
cDNA and genomic cloning of HRC, a human sarcoplasmic reticulum protein, and localization of the gene to human chromosome 19 and mouse chromosome 7.

Abstract Histidine-rich calcium binding protein (HRC) is a luminal sarcoplasmic reticulum (SR) protein of 165 kDa identified by virtue of its ability to bind 125 I-labeled lowdensity lipoprotein with high affinity after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (Hofmann et al., J. Biol. Chem. 264: 8260–8270, 1989). Its role in SR function is unknown. In this report, the gene encoding human HRC was localized to human chromosome 19 and mouse chromosome 7 by hybridization of a human HRC cDNA fragment to a panel of somatic cell hybrids. Known synteny between a portion of human chromosome 19 and a portion of mouse chromosome 7 and in situ hybridization of a biotin-labeled HRC probe to human chromosomes suggest a localization to a region corresponding to 19q13.3. The locus for myotonic dystrophy resides in the region 19q13.2–13.3. Therefore, we considered HRC , a muscle-specific gene, to possibly represent a “candidate gene” for myotonic muscular dystrophy. As a first step toward localizing HRC in relation to the myotonic dystrophy locus, we report the cloning of the human HRC gene, its intron-exon organization, and characterization of several informative polymorphisms to be used in future linkage studies in families with myotonic dystrophy. Of particular interest is an Alu -associated poly-d(GA) sequence located in an intron in the middle of the gene, and two stretches of acidic amino acids in the coding region of exon 1 that vary in length among different individuals.
Estimating Weight in Children With Down Syndrome

Objective. Significant attention has been paid to weight estimation in settings where scales are impractical or unavailable; however, no studies have evaluated the performance of published weight estimation methods in children with Down syndrome. This study was designed to evaluate the predictive performance of various methods in this population with well-established differences in height and weight for age. Methods. This was a prospective study of children aged 0 to 18 years with Down syndrome. Anthropometric measurements including height, weight, humeral length, and mid-upper arm circumference were collected and applied to 4 distinct weight estimation strategies based on age (APLS), length (Broselow), habitus (Cattermole), and length plus habitus (Mercy). Predictive performance was evaluated by examining residual error (RE), percentage error (PE), root mean square error (RMSE), limits of agreement, and intraclass correlation coefficients. Results. A total of 318 children distributed across age, gender, and body mass index percentile were enrolled. APLS and Mercy showed the smallest degree of bias (PE = 7.8 ± 24.5% and −3.9 ± 12.4%, respectively). Broselow suffered the most extreme underestimation (−63%), whereas the APLS suffered the greatest degree of overestimation (107%). Mercy demonstrated the highest intraclass correlation coefficient (0.987 vs 0.867-0.885) and predicted weight within 20% of actual in the largest proportion of participants (88% vs 40% to 76%). All methods were less robust in children with Down syndrome than reported for unaffected children. Conclusions. Mercy offered the best option for weight estimation in children with Down syndrome. Additional anthropometric data collected in this special population would allow investigators to refine existing weight estimation strategies specifically for these children.
In vitro transformation of mesenchymal cells derived from embryonic muscle into cartilage in response to extracellular matrix components of bone.

Abstract Subcutaneous implantation of demineralized diaphyseal bone matrix into rats induces cartilage and bone formation in vivo. When minced skeletal muscle is cultured on hemicylinders of demineralized bone in vitro, mesenchymal cells are transformed into chondrocytes. In the present investigation, the potential of extracellular matrix components of bone to trigger cartilage differentiation in vitro was examined. Extraction of bone hemicylinders with 6 M guanidine X HCl resulted in the absence of chondrogenesis in vitro and endochondral bone formation in vivo. Biologically inactive hemicylinders of bone were then reconstituted with the guanidine extract and also with partially purified components extracted from bone matrix and bioassayed. Reconstitution completely restored the ability to elicit chondrogenesis in vitro and endochondral bone differentiation in vivo. Reconstitution of the whole guanidine extract on Millipore filters coated with gels of tendon collagen (type I) and subsequent culture with minced skeletal muscle also resulted in cartilage induction in vitro. These observations show that the extracellular matrix of bone is a repository of factors that govern local cartilage and bone differentiation.
Of proneurotrophins and their antineurotrophic effects.

Neurotrophins perform essential processes throughout neural development. They signal through Trk receptor proteins, typically in association with a “low affinity” p75 NTR pan-neurotrophin co-receptor. Neurotrophins are synthesized as proproteins; the pro domains are removed proteolytically to yield the mature, presumably functional forms of the neurotrophins. Recent findings, however, have revealed a positive role for the proneurotrophins themselves. The proproteins bind with high affinity to the p75 NTR pan-neurotrophin receptor in the absence of Trks to initiate a separate set of signaling cascades that actively oppose the effects of the mature growth factors. These experiments suggest that the balance between pro- and mature neurotrophin plays a critical role in tuning downstream signaling. This view changes the neurotrophin field substantially and also points to the broader idea that the potential activities of precursor proteins deserve a closer look.
Citraconylated rabbit IgG.

Abstract Citraconic anhydride and ϵ-Amino hexanoic acid were reacted and ϵ,N-Citraconyl Aminocaproate (ENCTC) was prepared. The molar extinction coefficient of ENCTC at 280 nm = 116 M −1 , and at 241 nm = 7610 M −1 . These were used to determine the number of citraconyl groups covalently attached per mole of rabbit IgG. It was found that all free NH 2 groups could be readily citraconylated with virtually no loss of protein. O-citraconyl and N-citraconyl groups of rabbit IgG are labile at low alkaline, and near neutral pHs. There is some evidence, however, for stable citraconyl groups being formed which are not removed readily by treatment with NH 2 OH at pH 9·6.
Using Inquiry and Tree-Thinking to “March Through the Animal Phyla”: Teaching Introductory Comparative Biology in an Evolutionary Context

Biodiversity was originally taught in our Introductory Organismal Biology course at Michigan State University (LB144; freshman/sophomore majors) by rote memorization of isolated facts about organisms. When we moved to an inquiry-based laboratory framework to improve pedagogy, an unfortunate and unforeseen result was the loss of much of our study of biodiversity. In this paper, we describe the restructuring of LB144 to restore the study of biodiversity and organismal groups while retaining the benefits of an inquiry-based approach. The curricular intervention was accomplished through the creation and implementation of a four-week Comparative Biology laboratory stream. During this stream, student research teams recorded and organized observations that they made on a range of organisms and analyzed their data in a phylogenetic framework. During the stream, our students worked through a set of exercises designed to help them learn how to read, interpret, and manipulate phylogenetic trees. We placed particular emphasis on the concept that phylogenetic trees are hypotheses of relationship that can be tested with scientific data. This incorporation of phylogenies and phylogenetic analysis, or “tree-thinking,” into our students’ work provided an explicit synthetic evolutionary framework for their comparative biodiversity studies. End-of-stream products included a team phylogenetic analysis exercise and an individual comparative biology oral presentation.
Toxicity of calcium lonophore A23187 in monolayers of hypoxic hepatocytes

Abstract Increased cytoplasmic calcium has been implicated in hepatic necrosis induced by cytochrome P-450-mediated halocarbon metabolism; hepatic necrosis is exacerbated by hypoxia. It is known that addition of the calcium ionophore A23187 to a cell can mimic the metabolic causes of increased cytoplasmic calcium. In the present experiments, confluent monolayers of rat hepatocytes were exposed to A23187 (0.5–50 μ M ) under conditions of normoxia and hypoxia. The toxicity of A23187, as calculated by ED 50 values, was increased 18-fold during a 4-h incubation at 0.5% (5 μ M ) O 2 compared with 20% (212 μ M ) O 2 . The ED 50 values of A23187 were 0.92, 1.84, 10.98, and 16.81 μ M at 0.5, 1, 2, and 20% O 2 , respectively. The results demonstrate that small reductions in the oxygen concentrations normally encountered by pericentral hepatocytes (i.e., below 28 μ M ) may severely decrease the ability of these already compromised hepatocytes to manage perturbations in calcium homeostasis.
Conversion of trypsin to a functional threonine protease.

The hydroxyl group of a serine residue at position 195 acts as a nucleophile in the catalytic mechanism of the serine proteases. However, the chemically similar residue, threonine, is rarely used in similar functional context. Our structural modeling suggests that the Ser 195 → Thr trypsin variant is inactive due to negative steric interaction between the methyl group on the β-carbon of Thr 195 and the disulfide bridge formed by cysteines 42 and 58. By simultaneously truncating residues 42 and 58 and substituting Ser 195 with threonine, we have successfully converted the classic serine protease trypsin to a functional threonine protease. Substitution of residue 42 with alanine and residue 58 with alanine or valine in the presence of threonine 195 results in trypsin variants that are 102–104-fold less active than wild type in kcat/KM but >106-fold more active than the Ser 195 → Thr single variant. The substitutions do not alter the substrate specificity of the enzyme in the P1′– P4′ positions. Removal of the disulfide bridge decreases the overall thermostability of the enzyme, but it is partially rescued by the presence of threonine at position 195.
Elements of Map-Scale Structure

The primary objective of structural map making and map interpretation is to develop an internally consistent three-dimensional picture of the structure that agrees with all the data. This can be difficult or ambiguous because the complete structure is usually undersampled. Thus an interpretation of the complete geometry will probably require a significant number of inferences, as, for example, in the interpolation of a folded surface between the observation points. Constraints on the interpretation are both topological and mechanical. The basic elements of map-scale structure are the geometries of folds and faults, the shapes and thicknesses of units, and the contact types. This chapter provides a short review of the basic elements of the structural and stratigraphic geometries that will be interpreted in later chapters, reviews some of the primary mechanical factors that control the geometry of map-scale folds and faults, and examines the typical sources of data for structural interpretation and their inherent uncertainties.
Millimeter-wave bi-polar planar phaseless measurements and diagnostics: Characterization of a Ka-band patch array

In this paper, for the first time, the effectiveness of phaseless measurements and diagnostics for millimeter-wave antennas will be demonstrated using a Ka-Band planar rectangular patch array. Using a newly constructed millimeter-wave bi-polar planar antenna measurement system at UCLA, we will show the viability and advantages of using phaseless techniques to facilitate millimeter-wave antenna measurement. To achieve this, a Ka-band patch array was designed, fabricated, and measured with the system at an operating frequency of 31.2GHz. Two measurements, a full (amplitude and phase) measurement and a phaseless (amplitude only) measurement, were then conducted and processed to produce far-field patterns. These results were compared to verify the accuracy of the technique.
LPmerge: an R package for merging genetic maps by linear programming

Summary: Consensus genetic maps constructed from multiple populations are an important resource for both basic and applied research, including genome-wide association analysis, genome sequence assembly and studies of evolution. The LPmerge software uses linear programming to efficiently minimize the mean absolute error between the consensus map and the linkage maps from each population. This minimization is performed subject to linear inequality constraints that ensure the ordering of the markers in the linkage maps is preserved. When marker order is inconsistent between linkage maps, a minimum set of ordinal constraints is deleted to resolve the conflicts. Availability and implementation: LPmerge is on CRAN at http://cran.
Multirate simulation for high fidelity haptic interaction with deformable objects in virtual environments

Haptic interaction is an increasingly common form of interaction in virtual environment simulations. This medium introduces some new challenges. In this paper we study the problem arising from the difference between the sampling rate requirements of haptic interfaces and the significantly lower update rates of the physical models being manipulated. We propose a multirate simulation approach which uses a local linear approximation. The treatment includes a detailed analysis and experimental verification of the approach. The proposed method is also shown to improve the stability of the haptic interaction.
Structure of the cannabinoid receptor 1: homology modeling of its inactive state and enrichment study based on CB1 antagonist docking

Cannabinoid receptor 1 (CB1) antagonists have potential to be used clinically to treat obesity, but there are currently no such drugs on the market. Since no X-ray crystal structure is available for CB1, considerable attempts have been made to prepare CB1 protein homology models, but in this work we propose a new CB1 inactive state model which is specific to CB1 antagonists, as validated by its enrichment performance. We first built multiple CB1 homology models. The enrichment performance of these models was then systematically examined using two datasets. A small dataset that contains 72 highly active CB1 antagonists was docked into these models. Only one of the models was able to dock all the compounds. After minimization and followed by redocking, two more models were able to dock all the 72 compounds. Next, a large dataset that contains 181 active CB1 antagonists and 3439 inactive CB1 antagonists/decoy compounds was used to assess the enrichment performance of the 3 models. One of the models was found to have much better enrichment performance than the other 2 models. This best CB1 model will be used in future virtual screening studies.
Peripheral Vascular Stenosis in Apolipoprotein E-Deficient Mice Potential Roles of Lipid Deposition, Medial Atrophy, and Adventitial Inflammation

A systematic analysis of the distribution of advanced atherosclerotic lesions was undertaken in chow-fed, 9-month-old apolipoprotein (apo) E-deficient mice to identify sites amenable for study of mechanisms of formation of stenotic lesions. The arterial tree was dissected intact and included medium-sized arteries in the extremities as well as arteries of the head and neck. The most reproducible lesions were seen in the ascending aorta and in the carotid, femoral, and popliteal arteries. Casting of the vascular tree provided additional verification of the presence of lumen narrowing in the external branches of the carotid artery. Consistent with what has been observed in human atherosclerotic arteries, there was dilation in response to lesion growth and no correlation between lesion mass and lumen loss in the mouse arteries. This adaptation was especially true in the ascending aorta, where normal lumen size was maintained at atherosclerotic sites. In contrast, the external carotid arteries were stenotic in 9 of 12 animals. Here too, however, loss of lumen did not correlate with lesion mass but did correlate with adventitial inflammation and medial atrophy. Lumen narrowing also occurred most frequently at sites where extracellular cholesterol clefts were a prominent part of the lesion. These data suggest that the stenotic process in advanced atherosclerotic vessels may depend on death of medial smooth muscle cells, possibly in response to inflammatory changes in the plaque or adventitia.
Human memory and the storage of information

The amount of selective information in a message can be increased either by increasing the variety of the symbols from which it is composed or by increasing the length of the message. Psychological experiments indicate that the variety of the symbols is far less important than the length of the message in controlling what human subjects are able to remember. Two messages equal in length but differing in the amount of information per symbol are equally easy to memorize. This fact provides an opportunity for the effective use of recoding procedures and reveals the mental economy involved in organizing the materials we want to remember. An apparent exception to the rule that length, not variety, is the limiting factor in human memory occurs in the case of redundant messages. If two messages of the same length differ because one contains redundancy familiar to the learner and the other does not, the redundant message will usually be easier to learn and remember. In terms of the theory of information, redundancy can be viewed equally well as a reduction in the information per symbol or as a reduction in the effective length of the message. Psychologically, however, these two alternatives are not equivalent; redundancy permits a reorganization into familiar sequences in a way that effectively shortens the length of the message and so makes it easier to memorize, but this is not psychologically equivalent to reducing the amount of information per symbol. It is as if each storage register could accept any one of a tremendous variety of alternative symbols, but the number of registers available was quite limited. If we use these registers to store binary symbols, the storage is inefficient. If we group the binary symbols into sequences, give each sequence a different name, and store the recoded names, we can make much more efficient use of the registers. Familiar redundancy is helpful because it enables us to recode more efficiently. These results for human memory are all the more striking in view of the fact that the amount of information per symbol is a critically important variable controlling the accuracy of our perceptions.