cssi/SciSciGPT-SciSciNet huggingface dataset:
The impact of neighborhood park access and quality on body mass index among adults in New York City.

Abstract Objective To evaluate the association between adult individuals' body mass index (BMI) and characteristics of parks (size and cleanliness) in an urban environment taking into account the physical and social environments of the neighborhood. Methods Cross-sectional, hierarchical linear models were used to determine whether park effects were associated with BMI using self-reported height and weight data obtained from the Community Health Survey in New York City (2002–2006). Results Both the proportion of the residential zip code that was large park space and the proportion that was small park space had significant inverse associations with BMI after controlling for individual socio-demographic and zip code built environment characteristics (− 0.20 BMI units across the inter-quartile range (IQR) for large parks, 95% CI − 0.32, − 0.08; − 0.21 BMI units across the IQR for small parks, 95% CI − 0.31, − 0.10, respectively). Poorer scores on the park cleanliness index were associated with higher BMI, 0.18 BMI units across the IQR of the park cleanliness index (95% CI 0.05, 0.30). Conclusions This study demonstrated that proportion of neighborhoods that was large or small park space and park cleanliness were associated with lower BMI among NYC adults after adjusting for other neighborhood features such as homicides and walkability, characteristics that could influence park usage.
Effects of Discourse Mode on the Syntactic Complexity of Learning Disabled Students' Written Expression:

The purpose of this study was to investigate the effect of discourse mode on the syntactic complexity of the written expression of learning disabled students at three grade levels. A film without narration was used to elicit written language samples in each of the two discourse modes, description and argumentation. Two measures of syntactic complexity — average length of T-unit and Syntactic Density Score — were employed to determine differences between the two modes. In addition, sentence types and syntactic patterns were examined as indices of syntactic complexity. Results of the investigation and implications of these results are discussed.
Numerical simulation of entry flows of corn meal

Abstract Control volume formulation was used to calculate the entry flow of the corn meal. The contraction ratio was 6 and the half die angles were 30 °, 37.5 °, 45 ° and 90 °. To test the accuracy of the method, the calculation was first carried out for Newtonian fluid and low-density polyethylene. The numerically estimated entrance pressure drop for corn meal was compared with experimental values. Effects of die angles on entrance pressure drop and on the distribution of axial velocity were presented. The numerically estimated entrance pressure drop was lower than the experimental values, which can be mainly attributed to the constitutive equation used in this study, the power-law, which failed to predict the extensional behaviors of corn meal. It was also found that entrance pressure drop increased with increased die angle and there was an overshoot in axial velocity at the contraction. The convergence of the solutions was improved by using control volume formulation.
Airway Complications of Jet Ventilation in Neonates

Four cases of airway complications in infants surviving jet ventilation have been observed at the Children's Hospital of New Mexico. Two cases of necrotizing tracheobronchitis in preterm infants are presented: one was treated with bronchoscopy and removal of the necrotizing tissue; the second was placed on extracorporeal membrane oxygenation, prior to dilation of the affected area. A third child developed subglottic stenosis after intubation with an oversized jet endotracheal tube. A fourth child, with a history of prematurity and jet ventilation as a neonate, was found at 3 years of age to have tracheal webs in the lower third of his airway. Management and follow-up of these four cases, as well as a literature review of the known airway complications of jet ventilation, are presented.
The Strength and Cooperativity of KIT Ectodomain Contacts Determine Normal Ligand-Dependent Stimulation or Oncogenic Activation in Cancer

Summary The receptor tyrosine kinase KIT plays an important role in development of germ cells, hematopoietic cells, and interstitial pacemaker cells. Oncogenic KIT mutations play an important "driver" role in gastrointestinal stromal tumors, acute myeloid leukemias, and melanoma, among other cancers. Here we describe the crystal structure of a recurring somatic oncogenic mutation located in the C-terminal Ig-like domain (D5) of the ectodomain, rendering KIT tyrosine kinase activity constitutively activated. The structural analysis, together with biochemical and biophysical experiments and detailed analyses of the activities of a variety of oncogenic KIT mutations, reveals that the strength of homotypic contacts and the cooperativity in the action of D4D5 regions determines whether KIT is normally regulated or constitutively activated in cancers. We propose that cooperative interactions mediated by multiple weak homotypic contacts between receptor molecules are responsible for regulating normal ligand-dependent or oncogenic RTK activation via a "zipper-like" mechanism for receptor activation.
Construction of folate-conjugated pRNA of bacteriophage phi29 DNA packaging motor for delivery of chimeric siRNA to nasopharyngeal carcinoma cells

Nasopharyngeal carcinoma is a poorly differentiated upper respiratory tract cancer that highly expresses human folate receptors (hFR). Binding of folate to hFR triggers endocytosis. The folate was conjugated into adenosine 5′-monophosphate (AMP) by 1,6-hexanediamine linkages. After reverse HPLC to reach 93% purity, the folate–AMP, which can only be used for transcription initiation but not for chain extension, was incorporated into the 5′-end of bacteriophage phi29 motor pRNA. A 16:1 ratio of folate–AMP to ATP in transcription resulted in more than 60% of the pRNA containing folate. A pRNA with a 5′-overhang is needed to enhance the accessibility of the 5′ folate for specific receptor binding. Utilizing the engineered left/right interlocking loops, polyvalent dimeric pRNA nanoparticles were constructed using RNA nanotechnology to carry folate, a detection marker, and siRNA targeting at an antiapoptosis factor. The chimeric pRNAs were processed into ds-siRNA by Dicer. Incubation of nasopharyngeal epidermal carcinoma (KB) cells with the dimer resulted in its entry into cancer cells, and the subsequent silencing of the target gene. Such a protein-free RNA nanoparticle with undetectable antigenicity has a potential for repeated long-term administration for nasopharyngeal carcinoma as the effectiveness and specificity were confirmed by ex vivo delivery in the animal trial.
The attainment of specified objectives by medical students in different learning environments

Summary Medical students were provided with behavioural objectives for the problem solving phase of their curriculum. They were assigned for 11 weeks to various hospital settings that differed in the presence or absence of structured classes, the expertise of the teaching staff, the amount of instruction time and the types of learning experiences. At the end of that time, the students took the same examination to measure attainment of the objectives. The only variable that was associated with significantly different examination scores was presence or absence of structured classes.
The use of flotation isolation to modify important type a components in young adults

Abstract The Type A Behavior Pattern has been associated with increased risk for coronary-heart disease. Recently, some researchers in the field. including Friedman and colleagues, have attempted to modify global or component behaviors of the Type A pattern. However, early results have been compromised by methodological difficulties such as lack of controls or small sample size. Effective modification programs have also proved to be time-consuming and complex. This study utilized flotation isolation and compared this technique with a control condition of a darkened relaxed environment, as a short-term method for impacting on self-reported Type A behaviors. Twenty male and 20 female extreme Type A and Type B subjects were randomly placed in a flotation or control envlronment for one hour. Comparison of pre-and post-scores on various measures suggest a greater reduction in Type A characteristics such as hostility, tension, and anxiety in flotation isolation than in the more standard restricted stimuli environment.
Cadaveric morphometric analysis for atlantal lateral mass screw placement.

Objective Atlantal lateral mass screws provide an alternative to C1/C2 transarticular screws and, in some cases, can obviate the need for extending a fusion to the occiput. For these reasons, C1 lateral mass screws are becoming increasingly popular. However, the critical local anatomy and unfamiliarity with this new technique can make C1 screw placement more challenging. Methods Morphometric analysis was performed on 74 cadaveric spines obtained from the Department of Anatomy at the Keck School of Medicine, University of Southern California. Critical measurements were determined for screw entry points, trajectories, and lengths for application of the technique described by Harms and Melcher. Results The mean height and width for screw entry on the posterior surface of the lateral mass were 3.9 and 7.3 mm, respectively. The maximum medialized screw trajectory ranged from 25 to 45 degrees (mean, 33 degrees). The mean maximal screw length to obtain bicortical purchase was 22.5 mm, and the mean minimum screw depth was 14.4 mm. Screw depths varied on the basis of the entry point, trajectory, and vertebral morphology. The overhang of the posterior arch averaged 11.4 mm (range, 6.9-17 mm). All specimens could accommodate 3.5-mm lateral mass screws bilaterally with proper preparation of the entry site. Conclusion Significant variations in the morphology of C1 exist. However, the large size of the atlantal lateral mass makes screw placement forgiving. Preoperative computed tomographic scans and intraoperative fluoroscopy are useful in guiding proper screw placement. Close attention should be paid to preparation of the screw entry site.
Transfer of delayed cutaneous hypersensitivity with transfer factor

The effect of dialyzable transfer factor from 16 donors on transfer of delayed skin reactivity was studied in 20 patients with cellular immunodeficiency syndromes. Successful transfer of delayed hypersensitivity was achieved in 50 of the 89 opportunities. There were three additional instances in which recipients became reactive to antigens to which the donors were unresponsive. Four patients received multiple injections of transfer factor from donors who were unresponsive to candida; in no instance did a recipient become reactive to candida, although three became reactive to other donor-responsive antigens. The data also showed that conversions of skin responses by recipients occurred as independent events and not in all-or-none manner. The results of this investigation are interpreted as being compatible with antigen-specific activities in dialyzable transfer factor.
Dual-Credit in Kentucky.

Credit-based transition programs provide high school students with opportunities to jump start their college education. The Kentucky Community and Technical College System (KCTCS) offers college credit through dual-credit programs. While KCTCS dual-credit offerings have been successful in helping high school students start their college education before high school graduation, these offerings need to move from enrollment mechanisms to recruitment tools. This manuscript provides areas where more can be done to improve dual-credit offerings and make the change from enrollment tool to recruitment and completion tools.
Mucosal lymphatic-derived γδ T cells respond early to experimental Salmonella enterocolitis by increasing expression of IL-2Rα

To better understand the roles of gammadelta T cells in mucosal infection, we utilized Salmonella enterica serovar Typhimurium (Salmonella serovar Typhimurium) infection in cattle as it closely approximates Salmonella serovar Typhimurium-induced enterocolitis in humans. Protein and gene expression in alphabeta and gammadelta T cells derived from lymphatic ducts draining the gut mucosa in Salmonella serovar Typhimurium-infected calves were analyzed. In calves with enterocolitis, general gene expression trends in gammadelta T cells suggested subtle activation and innate response, whereas alphabeta T cells were relatively quiescent following Salmonella serovar Typhimurium infection. An increase in IL-2R alpha expression on gammadelta T cells from infected calves and results from in vitro assays suggested that gammadelta T cells were primed by Salmonella serovar Typhimurium LPS to better respond to IL-2 and IL-15. Together with gene expression trends in vivo, these data support early priming activation of target tissue gammadelta T cells during Salmonella serovar Typhimurium infection.
Efficient quantum-chemical geometry optimization and the structure of large icosahedral fullerenes

Abstract Geometry optimization is efficient using generalized Gaunt coefficients, which significantly limit the amount of cross differentiation for multi-center integrals of high-angular-momentum solid-harmonic basis sets. The geometries of the most stable C 240 , C 540 , C 960 , C 1500 , and C 2160 icosahedral fullerenes are optimized using analytic density-functional theory, which is parameterized to give the experimental geometry of C 60 . The calculations are all electron, the orbital basis set includes d functions and the exchange-correlation-potential basis set includes f functions. The largest calculation on C 2160 employed about 39000 basis functions.
Scalable Tree-Based Architectures for IPv4/v6 Lookup Using Prefix Partitioning

Memory efficiency and dynamically updateable data structures for Internet Protocol (IP) lookup have regained much interest in the research community. In this paper, we revisit the classic tree-based approach for solving the longest prefix matching (LPM) problem used in IP lookup. In particular, we target our solutions for a class of large and sparsely distributed routing tables, such as those potentially arising in the next-generation IPv6 routing protocol. Due to longer prefix lengths and much larger address space, preprocessing such routing tables for tree-based LPM can significantly increase the number of prefixes and/or memory stages required for IP lookup. We propose a prefix partitioning algorithm (DPP) to divide a given routing table into k groups of disjoint prefixes (k is given). The algorithm employs dynamic programming to determine the optimal split lengths between the groups to minimize the total memory requirement. Our algorithm demonstrates a substantial reduction in the memory footprint compared with those of the state of the art in both IPv4 and IPv6 cases. Two proposed linear pipelined architectures, which achieve high throughput and support incremental updates, are also presented. The proposed algorithm and architectures achieve a memory efficiency of 1 byte of memory for each byte of prefix for both IPv4 and IPv6. As a result, our design scales well to support either larger routing tables, longer prefix lengths, or both. The total memory requirement depends solely on the number of prefixes. Implementations on 45 nm ASIC and a state-of-the-art FPGA device (for a routing table consisting of 330K prefixes) show that our algorithm achieves 980 and 410 million lookups per second, respectively. These results are well suited for 100 Gbps lookup. The implementations also scale to support larger routing tables and longer prefix length when we go from IPv4 to IPv6. Additionally, the proposed architectures can easily interface with external SRAMs to ease the limitation of on-chip memory of the target devices.
Swallowing in Fetal Sheep

Swallowing was measured in fetal sheep by using electromagnetic flowmeter heads chronically implanted in the fetal esophagus. The fetus swallows 20 to 200 milliliters of amniotic fluid in two to seven discrete episodes per day. The episodes are 1 to 9 minutes in duration and occur at seemingly random intervals. Swallowing is influenced by the condition of the fetus and may be the first manifestation of eating and drinking behavior.
Work in progress: Changes in elementary teachers' Noticing of engineering Pre/Post professional development with engineering

The addition of engineering to many state standards has created a need for effective teacher professional development. The Institute for P-12 Engineering Research and Learning (INSPIRE) facilitated summer engineering workshops for teachers in grades two to four. Participants completed the Noticing Activity, an assessment meant to gauge teachers' ability to notice and discuss engineering and its role in society. This work in progress describes the coding system being developed to analyze teacher responses. Analysis of teacher responses to the Noticing Activity will be used to determine what teachers notice about engineering in society and, later, help study how teachers discuss engineering with their students. Results from the coding will be used for programmatic evaluation and revision.
Spectra and structure of organophosphorus compounds. LVII. Raman and infrared spectra, conformational stability, vibrational assignment and ab initio calculations of n-propyltetrafluorophosphorane☆

Abstract The Raman (3100 to 50 cm −1 ) and infrared (3100 to 50 cm −1 ) spectra of gaseous and solid n-propyltetrafluorophosphorane, C 3 H 7 PF 4 , have been recorded. Additionally, the Raman spectra of the liquids have been obtained with qualitative depolarization ratios. From these data, two conformers, trans and gauche, have been identified in the fluid states. The trans conformer is shown to be the most stable rotamer in both gaseous and liquid states, and the only conformer present in the solid. The enthalpy difference between the conformers has been determined from Raman variable temperature studies to be 107 ± 20 cm −1 (306 ± 57 cal/mol) for the vapor and 168 ± 38 cm −1 (480 ± 109 cal/mol) for the liquid. A complete vibrational assignment is proposed for the trans conformer as well as for the fundamentals of most of the heavy atom motions for the gauche conformer. The conformational stabilities and fundamental vibrational frequencies, which have been determined experimentally, are compared to those obtained from ab initio calculations employing the RHF/3–21G ∗ and RHF/6–31G ∗ basis sets. Additionally, the conformational stabilities and structural parameters have also been determined with the 6–31G ∗ basis set with electron correlation at the MP2 level. The barriers to internal rotation of the hydrocarbon skeleton and the PF 4 moiety, as well as the barrier to Berry pseudorotation of the axial and equatorial fluorine atoms, have been determined using ab initio calculations at various levels. These results are compared to corresponding quantities for some similar molecules.
Rotational effects on natural convection in a horizontal cylinder

A numerical computation is carried out to study the interaction of rotation and natural convection inside a finite horizontal cylinder. The natural convection is due to differential heating on the two ends, while the rotation is along the axis of the horizontal cylinder. The aspect ratio, length of the cylinder to its radius, is 2.0. The Grashof number is fixed at 1.43 × 106 with air as a working fluid. The effect of rotation is examined with Gr/Re2 from 7.0 × 10−2 to ∞, which covers the range from rotation dominated flow to buoyancy dominated flow. It is found that when rotational speed is relatively small or Gr/Re2 » 1, the effect of rotation is to render the spatial heat flux distribution more uniform. As the rotational speed increases, the heat transfer rate distribution on the end surfaces is more homogenous and its level is also reduced. When the rotational speed is sufficiently high (Gr/Re2 « 1.0), heat transfer is by conduction only and the whole fluid inside the enclosure rotates as a rigid body. It is shown that there exists a rotation speed range in which one can have both relatively high and uniform heat transfer rates on the end walls.
A portable pendulum for testing dynamic tissue failure susceptibility of potatoes

Abstract A portable pendulum for measuring the extent of dynamic tissue failure in potatoes and other materials over a wide range of conditions (impact damage) is described. It can be used to measure energy absorbed during impact, sample deformation, non-recoverable deformation, time taken for the indentor to deform the tuber and time for it to return to its original point of contact with the tuber. Measurements are made using an angular displacement transducer and interpreted by means of logic circuits.
Extrapulmonary inflammatory pseudotumor in children

Inflammatory pseudotumor (IPT), an unusual etiology of an intraabdominal mass, is typically heralded by fever, anemia, thrombocytosis, and systemic symptoms that bear a resemblance to an inflammatory diathesis. Two cases of IPT seen within a 1-year period are presented: an adrenal IPT simulating a neuroblastoma was seen in an 8-year-old girl, and IPT in the jejunal mesentery mimicked a sarcoma in a 9-year-old boy. Although IPTs are histologically benign, they can be locally aggressive and often mimic a malignancy both radiographically and grossly. This diagnosis is rarely considered in the differential diagnosis of an abdominal mass.
Penicillin-induced epileptiform activity in the hippocampal in vitro preparation

An in vitro preparation has been developed in which epileptogenesis in mammalian central nervous system tissue may be studied. Addition of sodium penicillin to the medium bathing slices of guinea pig hippocampus induced epileptiform activity similar to that seen in hippocampal penicillin foci in vivo. Epileptiform events were recorded as synchronous field potentials and correlated cellular bursts that occurred spontaneously and could be triggered by orthodromic stimulation. Intracellular recordings revealed that bursts were generated from large depolarization shifts in some neurons, while in others, burst discharges had little underlying baseline depolarization. This finding, and the presence of fast prepotentials in penicillin-treated preparations, suggested the involvement of dendritic activity in generation of epileptiform discharges.
Axial dispersion in turbulent flow through standard 90 degree elbows

Axial dispersion was studied experimentally for turbulent flow through a 1 1/4-in. piping system containing 90 deg. elbows. The Reynolds number range was 15,400 to 96,555. The imperfect pulse tracer technique was used with the axial dispersion numbers being obtained from the difference in variances of concentration-time curves observed at two points in the system. Elbows interconnected by short lengths of pipe with each succeeding one reversed so as to cause a change in the direction of flow, increased axial dispersion by 35 to 61% over that expected for straight pipe, while the same elbows turned so as to form a helix decreased the dispersion substantially; however, the amount of axial dispersion was still 8 to 22% greater than that observed for straight pipe. The equivalent lengths of the elbows depend upon both their arrangement and the Reynolds number. Closely placed, helically arranged elbows required equivalent lengths of from 2.9 to 5.1 diam., while a reversed arrangement required 6.9 to 11.6 diam. Elbows separated by a developing length and randomly arranged yielded an equivalent length range of 3.6 to 10.6 diam. The geometical l/d ratio of the elbows used was 2.05.
The St. Petersburg two-envelope paradox

The Two-Envelope Paradox: I am presented with two envelopes A and B containing money, and am told that one contains twice as much as the other. I am given envelope A, and am offered the options of keeping envelope A or switching to B. What should I do? I reason: (1) For any x, if I knew that A contained x, then the odds would be then that B contains either 2x or x/2, so the expected amount in B would be 5x/4. So (2) for all x, if I knew that A contained x, I would have an expected gain in switching to B. So (3) I should switch to B. But this seems clearly wrong, as my information about A and B is symmetrical. It is widely accepted that one's reasoning in this scenario should depend on one's initial probability distribution for the amounts in the envelopes. It is also widely accepted that if this distribution has a finite expected value, (1) and (2) are false, so the reasoning goes wrong. However, it is well known that there are certain distributions with infinite expected value such that although (1) is false, (2) is still true. For such distributions, the paradox seems to arise as strongly as ever, and there is no widespread agreement on how to handle it.1 To help diagnose the residual 'paradox', I offer the following variant, obtained by mixing two well-known scenarios: The St. Petersburg two-envelope paradox: I am presented with two envelopes, A and B. I am told that each of them contains an amount determined by the following procedure, performed separately for each envelope: a coin is flipped until it comes up heads, and if it comes up heads on the nth trial, 2n is put into the envelope. This procedure is performed separately for each envelope. I am given envelope A, and offered the options of keeping A or switching to B. What should I do? I reason: (0) Before opening the envelopes, the expected value in each is infinite. (1) For any x, if I knew that A contained x, then the expected value in B would still be infinite. So (2) for all x, if I knew that A contained x, I would have an expected gain in switching to B. So (3) I should switch to B. But this seems clearly wrong, as my information about A and B is symmetrical.
Point Prevalence, Clinical Characteristics, and Treatment Variation for Infants with Severe Bronchopulmonary Dysplasia.

Objectives Despite improvements in survival of preterm infants, bronchopulmonary dysplasia (BPD) remains a persistent morbidity. The incidence, clinical course, and current management of severe BPD (sBPD) remain to be defined. To address these knowledge gaps, a multicenter collaborative was formed to improve outcomes in this population. Study Design We performed a “snapshot” in eight neonatal intensive care units (NICUs) on December 17, 2013. A standardized clinical data form for each inpatient born at Results Of a total census of 710 inpatients, 351 infants were born at Conclusion The high point prevalence of sBPD and variable management among NICUs emphasizes the lack of evidence in guiding optimal care to improve long-term outcomes of this high-risk, understudied population.
Simplicial maps for progressive transmission of polygonal surfaces

We present a new method for (1) automatically generating multiple Levels Of Detail (LODs) of a polygonal surface, (2) progressively loading, or transmitting, and displaying a surface, and for (3) changing interactively the LOD when displaying. We build the LODs using any algorithm that performs edge collapses and certain vertex removals to simplify surfaces, and provides an ordered list of ordered vertex pairs (edge collapse specifications). We propose a Surface Partition for encoding surface LODs: we define vertex and triangle levels during simplification; vertices and triangles are partitioned and sorted according to their level, and are passed to the display algorithm in decreasing level order, one level at a time, together with a vertex representatives array. Each level of vertices and triangles, together with higher levels and the vertex representatives, form a valid surface. The vertex representatives array encodes a succession of simplicial maps between the highest resolution LOD and other LODs. We propose a data structure using a Directed Acyclic Graph (DAG) for recording a partial ordering among edge collapses, and varying the LODs across the surface. We describe an implementation of our method in VRML. Key-words : Simplicial Map, Edge Collapse, Vertex and Triangle Levels, Surface Levels of Detail, Surface Partition, Progressive Transmission and Display, Dynamic Simplification.
Weaning and Parent‐offspring Conflict: Variation Relative to Interbirth Interval in Bison

Weaning and parent-offspring conflict were examined in bison (Bison bison). Maternal care and interactions with offspring during the first year were compared between mothers that did or did not conceive 4–5 mo postpartum; unlike barren mothers, pregnant mothers ceased nursing late in the first year. Pre-estrus nursing bouts were shorter for pregnant mothers; however, neither overall nursing time nor other forms of maternal care differed between groups. Offspring of pregnant mothers spent more time resting in Months 1–5; their grazing time also increased more slowly, suggesting higher rates of parental investment for pregnant mothers. For both groups, time spent suckling decreased due to decreasing bout frequency rather than duration. As soon as mothers differed in reproductive status, nursing time and frequency diverged dramatically, increasing for barren while decreasing for pregnant mothers. However, interactions with offspring differed little. The percentage of suckling bouts ended by calves decreased in Months 1–9 for both groups. Frequencies of rejected suckling attempts and maternal aggression increased in Months 2–4 but not subsequently. Contrary to the expectation that parent-offspring conflict is associated with the end of nursing, maternal aggression and nursing interruptions decreased in frequency with time. Because changes in interactions were gradual, there was no clear weaning period, i.e. when maternal care decreases most and conflict increases. Such changes were greatest in Months 1–3; however, suckling continued for 6–18 mo afterward. It appears that weaning occurs gradually, through maturational changes more than through parent-offspring conflict.
Experimental identification and control of a flexible beam

Abstract Experimental parameter identification and tip position control of a flexible beam attached at one end to a motor shaft are discussed in this paper. Modelling and identification experiments, including discussion of sampling-time and input amplitude selection and a unique displacement sensor for measuring the tip-position are considered first. Then tip-position control using optimal control (Linear Quadratic) and “preview” control methods are demonstrated. Position control performances with and without tip position feedback are compared.
Authorial Identity: A Graduate Student Odyssey

Doctoral students who seek to become part of what Geertz called “intellectual villages” (Geertz 1983: 157) must acculturate themselves into the ways of being, knowing, and especially writing in an academic discourse community. In this autobiographical case study, I use the academic writing I produced as a doctoral student to explore the process of developing an academic identity. I analyzed my writing for the absence or presence of the following rhetorical strategies: referencing conventions, use or avoidance of the scholarly I, and use of questions in the text. This critical examination of my writing illustrates the ways in which I experimented with my emerging academic identity as I struggled to begin participating meaningfully in the ongoing conversation within the discourse community I sought to join.
Changing Patterns of Anal Canal Carcinoma in the United States

Purpose Persistent human papillomavirus infection is associated with squamous cell carcinoma of the anal canal (SCCA). With changing sexual behaviors, SCCA incidence and patient demographics may also have changed in recent years. Methods The Surveillance, Epidemiology, and End Results public-use data set from 1973 to 2009 was analyzed to determine incidence trends for and demographic factors characterizing SCCA. Joinpoint analyses identified time points when incidence rates changed. For comparison, similar analyses were conducted for anal adenocarcinoma. Results Joinpoint analyses identified 1997 as the single inflection point among 11,231 patients with SCCA, at which the slope of incidence rates statistically increased (1997 to 2009 v 1973 to 1996: risk ratio [RR], 2.2; 95% CI, 2.1 to 2.3). Annual percent change (APC) increased for all SCCA stages and was the greatest for anal carcinoma in situ (CIS; APC, 14.2; 95% CI, 10.2 to 18.4). Demographic changes characterizing later versus earlier time period inc...
Dynamical Mechanical Analysis and Curing Analysis of Fouling Release Coatings and Components

A commercially available fouling release (adsorbed foulants removed by shear flow) coating based on poly(dimethylsiloxane) and a commercial marine epoxy primer have been analyzed by diffusing wave spectroscopy and by thermal and dynamical mechanical methods. Diffusing wave spectroscopy reveals 7-9 distinct relaxation intervals over short (minutes) to long (20 hour) time scales. Several junctures of these intervals are shown to correlate with mechanically determined film formation parameters, such as set to touch times, tack free times, and dry through times. Thickness series of coatings made by casting illustrate similarities and distinct differences between the epoxy primer and poly(dimethylsiloxane)-based fouling release coating formulations. Several low temperature β transitions are resolved in the fouling release coatings in addition the α (T g ) transition in both formulations. A scaling analysis of the thickness series data shows that both the primer and the top coat exhibit a negative exponent for thickness; -0.77 for the epoxy; -1.2 for the top coat. Stress-strain experiments reveal further significant difference between these two types of elastomers. The elastic modulus for the epoxy is 1000-fold higher than for the topcoat. A small elastic modulus is thought to be key in the successful functioning of fouling release coatings. Analyses of substrate effects (wire mesh, fiberglass braid) and of coating or loading levels on dynamical mechanical properties, in comparison with thickness series of thin films are presented. The woven braid offers the advantage that it can be loaded more easily than can wire mesh substrates. The negative exponents show that thinner coatings may be more mechanically resilient than thicker coatings, as the ability to store and dissipate mechanical energy decreases as thickness increases.
Where are the Web factories: The urban bias of e–business location

The Internet has been considered the great equaliser for business, allowing distant locals to compete with large metropolitan regions. Recent research points to a different geography, where domains and connectivity cluster predominantly in large urban areas. The question remains, are new businesses of the Internet economy doing the same or avoiding metropolitan areas? This paper examines the head and branch locations of the top 40 e–business integration firms in the USA. The analysis of the distribution of these locations will provide insight to what regions most benefit from the Internet economy. Further, the data should provide a useful comparison to metropolitan trends for domain and connectivity agglomeration.
A resource-trading mechanism for efficient distribution of large-volume contents on peer-to-peer networks

In recent years, the rapid growth of peer-to-peer (P2P) networks has provided a new paradigm for content distribution. To improve the efficiency of a P2P system, it is important to provide incentives for the peers to participate and contribute their resources. Various attempts have been made to reward/penalize peers by providing service differentiation based on a requesting peer's history or reputation. However, in a truly distributed, non-cooperative environment, maintaining and preventing the untruthful revealing of such information within the community impose larger computation and communication overheads to the system. These problems are further magnified when large-volume contents are being distributed because of the length distribution processes and the update of history or reputation has to keep up with the distribution process. In this paper, we address the incentive provisioning problem for distribution of large-volume content in P2P networks, and present a "seeing-is-believing" incentive-compatible mechanism (protocol) in which a peer will decide how much resources will be assigned to which neighbors based on what it has experienced. The protocol applies a utility-based resource-trading concept where peers will maximize their contributions for a fair or better return, and we show that by adopting this protocol, the system will achieve Cournot Equilibrium. Furthermore, our protocol is light-weight, completely decentralized, and cheat-proof. Experimental results illustrate significant improvements on the distribution efficiency of our protocol over other adopted alternatives.
An elegant approach for stereocontrolled synthesis of furopyran building blocks

Abstract An elegant approach for stereocontrolled synthesis of furopyran (hexahydro-2 H -furo[3,2- b ]pyran) building blocks was reported. The key steps in the sequence involved an efficient intramolecular 3-oxidopyrylium-alkene [5+2] cycloaddition for the synthesis of cycloadduct 6 and Beckmann fragmentation of ketoxime 13 to yield the furopyrans ( 5a – c ).
User-oriented performance evaluation of data communication services: measurement results

The experimental design used by the Institute for Telecommunication Sciences (ITS) to measure the user information transfer performance parameters specified in American National Standard X3.102 on several US public data networks is discussed. The experimental design was developed in accordance with the data communication performance measurement procedures specified in a related American National Standard, X3.141. After summarizing the experimental design, with a focus on the interface events and boundaries used to measure block transfer time, a comparison is made with the CCITT X.130-series recommendations that establish performance standards for international packet-switched public data networks. Differences between the interface boundaries and events instrumented in these measurements and those specified in the CCITT X.130-series recommendations are discussed. >
Electromagnetic wave propagation in dispersive negative group velocity media

We study theoretically the propagation of electromagnetic waves in an infinite, isotropic, and homogenous, medium with both temporal and spatial dispersion included. We derive a partial differential equation connecting temporal and spacial dispersion to achieve negative group velocity. An exact solution of the equation is found and is shown to lead to negative-refraction media even when both ∈ and μ are positive. The formal solution suggests the possibility to engineer new artificial materials by carefully manipulating the spatial dispersion profile. We also analyze the power flow and suggests a path beyond the group velocity concept.
Evidence of a large‐scale gradient in the solar wind velocity

Measurements of the solar wind velocity have been compared at two widely separated locations using plasma data obtained in mid-1967 with Mariner 5, en route to Venus, and with the near-earth satellites Explorer 33, 34, and 35. A previous study of the propagation of interplanetary sector boundaries between Mariner and earth had implied the existence of a large-scale gradient in the velocity which we interpreted as a latitude gradient of approximately 13 km/s per degree of latitude. The present investigation extended this earlier study to the overall solar wind without regard to the presence of sector boundaries. Over 2000 hourly averages of the solar wind velocity which originated from essentially the same solar longitudes were compared at Mariner and earth. When Mariner 5 was still near earth, the velocity measurements were found to agree to within 7 km/s (≲2%). However, as the separation between Mariner and earth increased in radial distance, longitude, and latitude, the Explorer velocities became systematically larger than the corresponding Mariner velocities. By plotting both velocities as a function of the heliographic longitude at the instant that the solar wind passed the heliocentric distance of Mariner 5, it was possible to observe directly the systematic velocity differences. Several regression analyses of the Mariner and Explorer velocities were carried out to obtain a quantitative measure of the velocity differences. In addition to the 1-hour averages, 1-, 2-, and 4-day averages were analyzed to allow for the possible effect of persistence (i.e., a nonzero autocorrelation at lags of ≅ 1 day). All of these analyses yielded statistically significant departures which implied higher velocities at earth than at Mariner. In 4 months these velocity differences had increased on the average to 80 km/s (≅20%). The regression analysis results are in excellent agreement with the results obtained from the sector boundary propagation study. This agreement shows conclusively that the gradient cannot be attributed to stream-stream interactions or other possible acceleration mechanisms operating in the vicinity of sector boundaries. It is evident that a large-scale velocity gradient existed during this interval and was a general property of the solar wind. The quantitative agreement between the two studies implies that the most plausible interpretation of the gradient is that the solar wind velocity is latitude dependent.
Wild Shanghai Grass

OCTOBER 133, Summer 2010, pp. 75–105. © 2010 Molly Nesbit. In late April 1927 the writer Lu Xun sat as a refugee in the southern Chinese city of Guangzhou and wrote a preface to his new group of prose poems, which he was calling Wild Grass. “When I am silent, I feel replete,” he began. “As I open my mouth to speak, I am conscious of emptiness.” Words came to him. Past life had died. Dead life had decayed. From its clay, no trees grew, only wild grass. “I love my wild grass,” he wrote, “but I detest the ground which decks itself with wild grass.” He pointed to the fires underground that would one day erupt red and devour it. At that point he would laugh out loud and sing, he claimed, and he repeated this laughing and singing, because this fierce turn of events was the fair proof that he had lived.1 The poems that followed had been written to stand apart from the fray of the press. Pulled back and collected, they were a motley group. Freeform meditations rife with inversions, vicious observations, visions exploding; cackling, tart, wafting, they were his dreams, he said—his wild grass. These pieces were not uniform. He shifted voices and cadences. He gave them titles that charted no path: “The Shadow’s Leave-taking,” “Snow,” “The Passer-By,” “Tremors of Degradation,” “The Wise Man, the Fool, and the Slave.”
Decoupling approximation for the nonlinear-optical response of composite media

A nonlinear decoupling approximation (NDA) is described for calculating the nonlinear-optical response of composite materials. The NDA is used in conjunction with the effective-medium approximation for the linear response to calculate the effective third-order susceptibility, χe, of model metal–insulator and semiconductor–insulator composites as a function of frequency and composition. It is found that the ratio χe can be strongly enhanced relative to χ1, the corresponding third-order nonlinear susceptibility of a pure constituent in bulk. The enhancement is found to be sensitive to composite topology as well as to composition. The nonlinear susceptibility of randomly oriented nonlinear ellipsoidal particles in a linear host is calculated in the dilute limit. The susceptibilities of the model composites are also shown to be strongly influenced by particle shape.
Assignment of Downfield Proton Resonances in Purine Nucleoside Phosphorylase‚Immucillin-H Complex by Saturation-Transferred NOEs †

Purine nucleoside phosphorylase (PNP) catalyzes N-ribosidic bond phosphorolysis in 6-oxypurine nucleosides and deoxynucleosides to form purine and α-d-phosphorylated ribosyl products. The transition state has oxacarbenium ion character with partial positive charge near C-1‘, ionic stabilization from the nearby phosphate anion, and protonation at N-7 of the purine. Immucillin-H (ImmH) has a protonated N-7 and resembles the transition-state charge distribution when N-4‘ is protonated to the cation. It binds tightly to the PNPs with a Kd value 56 pM for human PNP. Previous NMR studies of PNP·ImmH·PO4 have shown that the N-4‘ of bound ImmH is a cation and is postulated to have a significant contribution to its tight binding. Several unassigned downfield proton resonances (>11 ppm) are specific to the PNP·ImmH·PO4 complex, suggesting the existence of strong hydrogen bonds. In this study, two of the proton resonances in this downfield region have been assigned. Using 15N-7-labeled ImmH, a resonance at 12.5 ppm ...
Reporting adverse events in randomized controlled trials.

Purpose How randomized controlled trial results are reported may minimize concerns and detection of adverse side effects. We aimed to describe the methods of reporting adverse events in these published trials. Methods Five frequently cited journals were investigated: Annals of Internal Medicine, British Medical Journal, JAMA, The Lancet, and the New England Journal of Medicine. For each journal, all randomized controlled trials conducted on the use of a medication were selected from January 2000 through June 2003. All issues of each journal were reviewed manually. Information retrieved included any mention of adverse events in the abstract, methods, results, or discussion section of the article; or inclusion of adverse events data in tables or figures. We also cataloged whether there was a separate subheading in the results section for reporting adverse events. Reports of trials that referred to methods described in a previous report were excluded. Results There were 521 eligible articles. Explicit mention of adverse events was in 328 (63%) of abstracts (range 47–66%), 380 (73%) of methods (range 51–81%), 464 (89%) of results (range 80–95%), and 250 (48%) of tables (range 31–49%). There was a separate subheading for adverse events in 240 (46%) (range 22–64%) of the eligible articles. Conclusion There is variation among authors and journals as to the location of reporting adverse events and the means by which it is done. Authors and editors should include specific information on adverse events when reporting the results of randomized controlled trials. It would be ideal if there was more consistency among authors and journals as to how these adverse events are described. Copyright © 2006 John Wiley & Sons, Ltd.
Contributions of Managerial Levels: Comparing MLB and NFL

Sports differ according to the number of players, interdependencies among them, complexity of strategy, and other dimensions. For example, baseball has been described as ‘an individual game in which a team score is kept’. These differences suggest differences in the relative importance of managerial inputs: owners, general managers, and managers (or head coaches). Using panels over 1970–2011, I estimate performance production regressions for Major League Baseball and the National Football League that permit the relative importance of these managerial inputs to be assessed within and across sports while taking explicit account of the hierarchical structure of management levels. In addition, with predicted individual effects, I present rankings of best and worst managers, general managers, and owners. Copyright © 2013 John Wiley & Sons, Ltd.