cssi/SciSciGPT-SciSciNet huggingface dataset:
Understanding track substructure behavior: Field instrumentation data analysis and development of numerical models

Abstract Numerous studies have targeted using numerical modeling, field instrumentation, or combinations of both to gain insight into track substructure behavior under loading. In-depth understanding of track substructure behavior serving both passenger and freight trains is critical to developing suitable design and maintenance/rehabilitation methods to ensure adequate performance under loading. This manuscript presents findings from a recently completed study involving advanced instrumentation and numerical modeling to investigate track substructure-related issues at several problematic railroad bridge approaches in the United States. Multi-Depth Deflectometers (MDDs) were installed to measure transient as well as plastic deformations experienced by track substructure layers under loading. Strain gauges were installed on the rail web to measure the vertical wheel loads applied during train passage. Data from the field instrumentation was used to make inferences regarding the relative contributions of different substructure layers towards the differential movement problem. A 3-D Finite Element (FE) model was developed to further understand the behavior of the instrumented locations, and was calibrated using the field instrumentation data. An elastic layered track analysis program, GEOTRACK, was first used to iteratively backcalculate individual track substructure layer moduli from the field measurements; these backcalculated modulus values were subsequently used in the FE model to predict track response under transient loading conditions. Modulus values estimated for the ballast layer were found to be significantly affected by the presence of gaps at the tie-ballast interface at track transitions. Once validated, the model was further modified to match transient displacement results acquired in the field using a quasi-static moving load approach. Good agreement was found between the model predictions and field instrumentation results. Development of advanced numerical models augmented by field instrumentation data can facilitate the design and maintenance of well-performing track structures.
End-of-Trial Health Outcomes in Look AHEAD Participants who Elected to have Bariatric Surgery.

OBJECTIVE This study examined end-of-trial health outcomes in participants in the Action for Health in Diabetes (Look AHEAD) trial who had bariatric surgery during the approximately 10-year randomized intervention. METHODS Data were obtained from the Look AHEAD public access database of 4,901 individuals with type 2 diabetes and overweight/obesity who were assigned to intensive lifestyle intervention (ILI) or a diabetes support and education (DSE) control group. Changes in outcomes in participants who had bariatric surgery were compared with those in participants with BMI ≥ 30 kg/m2 who remained in the ILI and DSE groups. RESULTS A total of 99 DSE and 97 ILI participants had bariatric surgery. At randomization, these 196 participants were significantly younger and more likely to be female and to have higher BMI than the remaining ILI (N = 1,972) and DSE (N = 2,009) participants. At trial's end, surgically treated participants lost 19.3% of baseline weight, compared with 5.8% and 3.3% for the ILI and DSE groups, respectively, and were more likely to achieve partial or full remission of their diabetes. CONCLUSIONS The large, sustained improvements in weight and diabetes observed in this self-selected sample of surgically treated participants are consistent with results of multiple randomized trials.
Applying Number Sense to Problem Solving.

NCTM's Commission on Standards for School Mathematics (1987) has identified problem solving and number sense as important components of an effective mathematics program. This emphasis is generating attempts to understand the problem-solving process better and to incorporate the results into classroom practice. In keeping with the thrust, this article discusses the interrelationships between problem solving and number sense in light of difficulties experienced by students participating in the problem-solving process. Earlier research on problem solving is reflected in the content found in most textbook series by the use of some variation of Polya's (1973) fourstep plan. Essentially, the four steps are (1) understand the problem, (2) develop a plan, (3) carry out the plan, and (4) look back. Although it builds a framework for the problem-solving process, progression through these steps does not guarantee students' success. In fact, many students approach problem-solving tasks apprehensively. At least two steps of the solution process can cause trouble for students. On the one hand, the four problem-solving steps may be memorized and recited, but students may still be
Chemoprevention of Cancer: From Nutritional Epidemiology to Clinical Trials

This chapter considers the evidence for chemoprevention of the more common cancers, breast, colon, lung, and prostate, emphasizing the findings from stage III clinical trials. Nutritional epidemiology has generated a number of provocative findings regarding the role of dietary elements in cancer risk and prevention. These findings have led to the hope that the most important bioactive compounds in foods might be isolated and administered to populations, much as vitamins are used to ward off nutritional deficiency diseases. Therapeutic agents in widespread use, including nonsteroidal, anti-inflammatory, and hormone-focused drugs, have also been proposed as chemopreventive agents. To date, formal testing of these agents in randomized, placebo-controlled trials has indicated that their preventive effects are modest to negligible or that their toxicities are unacceptable for use in average-risk populations. An approach which may prove fruitful for chemoprevention may be for testing to be undertaken in populations at elevated risk of cancer: individuals with premalignant lesions, such as intraepithelial neoplasms of the colon or prostate, or even with early cancers. In such populations, toxicity may be more acceptable than in average-risk populations.
Duality in Countably Infinite Linear Programs

Duality results on countably infinite linear programs (CILPs) are scarce. Roughly speaking, one fundamental hurdle is as follows. Subspaces that admit an interior point, which is a sufficient condition for a zero duality gap, yield a dual problem where the constraints cannot be expressed using the ordinary transpose of the primal doubly-infinite constraint matrix. Subspaces that do allow us to write the dual using this ordinary transpose do not admit an interior point. This has recently been called the "Slater conundrum." We find a way around this hurdle. We propose a pair of primal-dual spaces with three properties: (i) the series in the primal and dual objective functions converge; (ii) the series defined by the rows and columns of the primal constraint matrix converge; and (iii) the order of sums in a particular iterated series of a double sequence defined by the primal constraint matrix can be interchanged so that the dual is defined by the ordinary transpose. Weak duality and complementary slackness are then immediate. Instead of using interior point conditions to establish a zero duality gap, we call upon the planning horizon method. When the series in the primal and dual constraints are continuous, we prove that strong duality holds if a sequence of optimal solutions to finite-dimensional truncations of the primal and dual CILPs has an accumulation point. We show by counterexample that the requirement that such an accumulation point exist cannot be relaxed. We also prove that the Lagrangean of our CILPs provides a linear support to the primal optimal value function. Finally, we establish that saddle points of the Lagrangean are equivalent to complementary feasible solutions of our CILPs. Our results are illustrated using several examples, and are also applied to countable-state Markov decision processes and to a problem in robust optimization.
Palliative Care in the Neuro-ICU: Perceptions, Practice Patterns, and Preferences of Neurointensivists

The proportion of hospitals with specialist palliative care services in the USA has increased substantially over the past decade. Severe acute brain injury presents with unique challenges, especially regarding quality of life. The growth and increased recognition of neurocritical care as a subspecialty has not been paralleled by studies regarding how best to integrate palliative care for this unique patient population. Thus, we surveyed members of the Neurocritical Care Society (NCS) to explore current practice patterns, perceptions, and preferences regarding integration of palliative care in the neurological intensive care unit (Neuro-ICU). We created a 19-item survey using SurveyMonkey to assess practice patterns, perceptions, and preferences of neurointensivists regarding integration of palliative care in the Neuro-ICU. The survey, approved by the NCS research committee, was distributed to all active members of the NCS. A total of 424 NCS members representing 19% of the 2200 list serve members completed the survey. The majority (58%) of respondents were attending physicians, who worked primarily in a dedicated Neuro-ICU (67%), at university affiliated academic medical centers (65%). Palliative care consultations are utilized infrequently (< 11%) by the majority of the respondents (59%). The most common indication for a palliative consultation was to discuss goals of care and make treatment decisions (73%). A large majority (77%) either agreed or strongly agreed that palliative care services were utilized in the management of difficult cases apart from discussions regarding withdrawal of life sustaining therapy. Palliative care needs of Neuro-ICU patients were considered different from patients in other ICUs by the majority of respondents (66%). Our study provides insights into the current perceptions, practice patterns, and preferences of neurointensivists as it relates to palliative care consultation in the Neuro-ICU.
Smart-Hop Arbitration Request Propagation: Avoiding Quadratic Arbitration Complexity and False Negatives in SMART NoCs

SMART-based NoC designs achieve ultra-low latencies by enabling flits to traverse multiple hops within a single clock cycle. Notwithstanding the clear performance benefits, SMART-based NoCs suffer from several shortcomings: each router must arbitrate among a quadratic number of requests, which leads to high costs; each router independently makes its own arbitration decisions, which leads to a problem called false negatives that causes throughput loss. In this article, we propose a new SMART-based NoC design called SHARP that overcomes these shortcomings. Our evaluation demonstrates that SHARP increases throughput by up to 19% and average link utilization by up to 24% by avoiding false negatives. By avoiding quadratic arbitration, our evaluation further demonstrates that SHARP reduces the wiring and area overhead significantly.
The Subjective Impressions of Sixth Grade Urban Adolescents Concerning Their Ability to Achieve Personal Goals

The current study investigated the subjective impressions of sixth grade participants in Going for the Goal (GOAL), a ten-workshop peer-led life skills program, about their ability to get what they want. Four focus groups from three middle schools in a large Southeastern urban area school district were conducted. Analysis of the transcripts from these focus groups indicated that the sixth graders discussed changes within themselves that are consistent with important developmental advances in cognition that occur during early adolescence. The results of this empirical study provide suggestions for the modification of expectations concerning the impact of positive youth development programs.
Review of Canadian Curriculum Studies: A Métissage of Inspiration/Imagination/Interconnection

A Review of Canadian Curriculum Studies: A Metissage of Inspiration/Imagination/Interconnection
Single-cell RNAseq analysis of testicular germ and somatic cell development during the perinatal period

Pro-spermatogonia (SG) serve as the gateway to spermatogenesis. Using single-cell RNA sequencing (RNAseq), we studied the development of ProSG, their SG descendants and testicular somatic cells during the perinatal period in mice. We identified both gene and protein markers for three temporally distinct ProSG cell subsets, including a migratory cell population with a transcriptome distinct from the previously defined T1- and T2-ProSG stages. This intermediate (I)-ProSG subset translocates from the center of seminiferous tubules to the spermatogonial stem cell (SSC) 'niche' in its periphery soon after birth. We identified three undifferentiated SG subsets at postnatal day 7, each of which expresses distinct genes, including transcription factor and signaling genes. Two of these subsets have the characteristics of newly emergent SSCs. We also molecularly defined the development of Sertoli, Leydig and peritubular myoid cells during the perinatal period, allowing us to identify candidate signaling pathways acting between somatic and germ cells in a stage-specific manner during the perinatal period. Our study provides a rich resource for those investigating testicular germ and somatic cell developmental during the perinatal period.
Impact of selective adenosine A2A receptor agonists on cardiac imaging feeling the lightning, waiting on the thunder.

Approximately equal numbers of thunderstorms and cardiac stress imaging studies occur daily around the world (approximately 40,000). The U.S. National Center for Health Statistics reported 1,318 deaths from lightning from 1980 to 1995 ([1][1]). In the same era, multi-center registries of 89,973
Modeling Household Food Insecurity with a Polytomous Rasch Model

The Household Food Security Survey Module (HFSSM) is an 18-item scale created and maintained by the US Department of Agriculture (USDA) that measures food insecurity in the United States. The HFSSM includes ten items that reference food hardships among adults in the household and eight items that reference food hardships among children. The scale was created and maintained using a dichotomous Rasch model (Engelhard et al., Educ Psychol Meas 78:1–19, 2017). However, the item responses that are collected for nine of the items are polytomous that are later dichotomized for creating the final scale. In 2006, the Committee on National Statistics (CNSTAT) reviewed the HFSSM and the USDA’s procedures for measuring food insecurity. They suggested modeling polytomous item responses with a polytomous model instead of dichotomizing item responses (Wunderlich and Norwood, Food insecurity and hunger in the United States: an assessment of the measure. The National Academies Press, Washington, DC, 2006). The purpose of this study is to explore modeling polytomous HFSSM items with a partial credit model, building on Nord’s (Assessing potential technical enhancements to the US household food security measures. US Department of Agriculture, Economic Research Service, 2012) work on the partial credit model and the HFSSM. The polytomous Rasch model is compared to the dichotomous Rasch model currently used by the USDA. The data suggest that the polytomous model provides better model-data fit, explaining 62% of the variation as opposed to 58% with the dichotomous model. The use of a polytomous model increases the precision of the estimates of food insecurity.
Human brain evolution: Emerging roles for regulatory DNA and RNA.

Abstract Humans diverge from other primates in numerous ways, including their neuroanatomy and cognitive capacities. Human-specific features are particularly prominent in the cerebral cortex, which has undergone an expansion in size and acquired unique cellular composition and circuitry. Human-specific gene expression is postulated to explain neocortical anatomical differences across evolution. In particular, noncoding regulatory loci are strongly linked to human traits, including progenitor proliferation and cortical size. In this review, we highlight emerging noncoding elements implicated in human cortical evolution, including roles for regulatory DNA and RNA. Further, we discuss the association of human-specific genetic changes with neurodevelopmental diseases.
Chromatographic separation of diastereoisomeric esters. I. Lactate and mandelate of butanol-2.

Abstract A chromatographic procedure is described in which aqueous solutions of dl -sec.-butyl d (−)-mandate and pure water were fed alternately to a column, 10 m × 1.29 cm2, of Dowex 50 W–X2. The time required for the chromatography was 680 h. About 7 mmole of d -sec.-butyl d -mandelate (contained in 1.1 l of water) and an equal amount of l -sec-butyl d -mandelate (contained in 2.4 l of water) were isolated. Evidence is presented that much larger yields of the active sec.-butyl d -lactates can be obtained under approximately the same conditions because of the much greater solubility of the lactates.
Optimizing Equational Programs

Equational programming [HO82b] involves replacing subterms in a term according to a set of equations or rewrite rules. Each time an equation is applied to the term, the subterm that matches the left hand side of the equation is replaced by the corresponding right hand side. In that process several nodes of the term tree are created. Some of these nodes may later turn out to be useless, and will be reclaimed.
Flow Control Protocols

A packet-switched network may be thought of as a distributed pool of productive resources (channels, buffers, and switching processors) whose capacity must be shared dynamically by a community of competing users (or, more generally, processes) wishing to communicate with each other. Dynamic resource sharing is what distinguishes packet switching from the more traditional circuit-switching approach, in which network resources are dedicated to each user for an entire session. The key advantages of dynamic sharing are greater speed and flexibility in setting up users connections across the network and more efficient use of network resources after the connection is established.
Bounding the Effective Yield Behavior of Mixtures

The yield surface of a mixture of elastic/plastic materials is examined through mathematical techniques. A variational principle is derived from the local yield behavior (which may be anisotropic) and is used to generate upper bounds on the effective yield surface of the mixture. These bounds effectively reduce estimates on the nonlinear problem of yield to estimates on the elastic properties of mixtures oflinearly elastic“reference materials.” Upper bounds obtained from the variational principle are shown to be tighter than previous bounds, provided one uses a linear bound which is tighter than the arithmetic-mean bound. Finally, explicit bounds are derived for the yield surface of anisotropic mixtures of two von Mises type materials when one phase takes the form of ellipsoidal inclusions embedded in a matrix of the second phase, and difficulties arising in applications to polycrystals are discussed.
Adaptation Bridges and Barriers in Water Planning and Management: Insight from Recent Extreme Droughts in Arizona and Georgia1

Abstract: It is critical to understand the ability of water management to prepare for and respond to the likely increasing duration, frequency, and intensity of droughts brought about by climate variability and change. This article evaluates this ability, or adaptive capacity, within large urban community water systems (CWSs) in Arizona and Georgia. It analyzes interview data on the bridges and barriers to adapting water management approaches in relation to extreme droughts over the past decade. This study not only finds levers for building adaptive capacity that are unique to each state but also identifies several unifying themes that cut across both cases. The interviews also show that a particular bridge or barrier, such as state regulation, is not universally beneficial or detrimental for building adaptive capacity within each state. Such knowledge is useful for improving water and drought management and for understanding how CWSs might prepare for future climate variability and change by removing the barriers and bolstering the bridges in efforts to build adaptive capacity.
Enhancement of head and neck squamous cell carcinoma proliferation, invasion, and metastasis by tumor-associated fibroblasts in preclinical models.

Background Head and neck squamous cell carcinoma (HNSCC) has had little improvement in mortality rates in decades. A clearer understanding of the HNSCC tumor microenvironment will aid in finding more effective targeted therapies for this disease. Tumor-associated fibroblasts (TAFs) are the largest stromal cellular components of the tumor microenvironment in HNSCC. Methods We isolated TAFs from clinical HNSCC cases and propagated in vitro. The effects of TAF-secreted paracrine factors on in vitro HNSCC migration, invasion, and proliferation was assessed. The effect of TAFs on HNSCC growth and metastases was determined in an orthotopic floor-of-the-mouth tumor model. Results TAF-conditioned media increased HNSCC cell migration, invasion, and proliferation. TAFs increased HNSCC tumor growth and metastases in vivo. Conclusion TAFs play a major role in increasing tumor growth and metastasis in HNSCC. Targeting the tumor stroma may be important to reduce the rate of HNSCC metastasis. © 2013 Wiley Periodicals, Inc. Head Neck 36: 385–392, 2014
Both Protein Kinase A and Mitogen-Activated Protein Kinase Are Required in the Amygdala for the Macromolecular Synthesis-Dependent Late Phase of Long-Term Potentiation

The lateral amygdala (LA) is thought to be critical for the specific acquisition of conditioned fear, and the emotionally charged memories related to fear are thought to require a form of synaptic plasticity related to long-term potentiation (LTP). Is LTP in the lateral amygdala enduring, and, if so, does it require gene expression and the synthesis of new protein? Using brain slices, we have examined the molecular-signaling pathway of LTP in the cortico-amygdala and the thalamo-amygdala pathways. We find that a single high-frequency train of stimuli induces a transient LTP (E-LTP); by contrast, five repeated high-frequency trains induce an enduring late phase of LTP (L-LTP), which is dependent on gene expression and on new protein synthesis. In both pathways the late phase of LTP is mediated by protein kinase A (PKA) and mitogen-activated protein kinase (MAPK). Application of the adenylyl cyclase activator forskolin induced L-LTP in both pathways, and this potentiation is blocked by inhibitors of protein synthesis. The late phase of LTP also is modulated importantly by β-adrenergic agonists. An inhibitor of β-adrenergic receptors blocks L-LTP; conversely, application of a β-adrenergic agonist induces the L-LTP. Immunocytochemical studies show that both repeated tetanization and application of forskolin stimulate the phosphorylation of cAMP response element-binding proteins (CREB) in cells of the lateral nucleus of the amygdala. These results suggest that PKA and MAPK are critical for the expression of a persistent phase of LTP in the lateral amygdala and that this late component requires the synthesis of new protein and mRNA.
From Soul to Mind: The Emergence of Psychology, from Erasmus Darwin to William James

"Trailblazing history. . . . After presenting a brilliant kaleidoscope of 18th- and 19th-century writings, Reed concludes that philosophy broke away from psychology, not the reverse, and that psychology is the poorer for it. . . . Reed uncovers and makes accessible an intellectual treasure-trove that will change the way we think about the last 250 years."-Library Journal "Intellectually challenging . . . informative and rewarding."-Kirkus Reviews "Reed is a person who thinks in an uncluttered way as well as writes so. His history is a splendid achievement beautifully crafted, sensibly and wisely thought through."-William Kessen In this lively and original account of psychology's formative years, the late Edward S. Reed describes the attempts of nineteenth-century thinkers and practitioners to make psychology into a science. Setting psychological developments within the social, religious, and literary contexts of the time, Reed counters the widespread belief that psychology emerged from philosophy and shows that the reverse is true.
Tyrosine Modification Is Not Required for Myeloperoxidase-induced Loss of Apolipoprotein A-I Functional Activities

Apolipoprotein A-I (apoAI), the major protein of high density lipoprotein, plays an important role in reverse cholesterol transport via its activity as an ABCA1-dependent acceptor of cellular cholesterol. We reported recently that myeloperoxidase (MPO) modification of apoAI inhibits its ABCA1-dependent cholesterol acceptor activity (Zheng, L., Nukuna, B., Brennan, M. L., Sun, M., Goormastic, M., Settle, M., Schmitt, D., Fu, X., Thomson, L., Fox, P. L., Ischiropoulos, H., Smith, J. D., Kinter, M., and Hazen, S. L. (2004) J. Clin. Invest. 114, 529–541). We also reported that MPO-mediated chlorination preferentially modifies two of the seven tyrosines in apoAI, and loss of parent peptides containing these residues dose-dependently correlates with loss in ABCA1-mediated cholesterol acceptor activity (Zheng, L., Settle, M., Brubaker, G., Schmitt, D., Hazen, S. L., Smith, J. D., and Kinter, M. (2005) J. Biol. Chem. 280, 38–47). To determine whether oxidative modification of apoA-I tyrosine residues was responsible for the MPO-mediated inactivation of cholesterol acceptor activity, we made recombinant apoAI with site-specific substitutions of all seven tyrosine residues to phenylalanine. ApoAI and the tyrosine-free apoAI were equally susceptible to dose-dependent MPO-mediated loss of ABCA1-dependent cholesterol acceptor activity, as well as lipid binding activity. MPO modification altered the migration of apoAI on SDS gels and decreased its α-helix content. MPO-induced modification also targeted apoAI tryptophan and lysine residues. Specifically, we detected apoAI tryptophan oxidation to mono- and dihydroxytryptophan and apoAI lysine modification to chlorolysine and 2-aminoadipic acid. Thus, tyrosine modification of apoAI is not required for its MPO-mediated inhibition of cholesterol acceptor activity.
An experimental comparison of the effectiveness of computers and humans as search intermediaries.

An experimental computer intermediary system, CONIT, that assists users in accessing and searching heterogeneous retrieval systems has been enhanced with various search aids. Controlled experiments have been conducted to compare the effectiveness of the enhanced CONIT intermediary with that of human expert interme diary search specialists. Some 16 end users, none of whom had previously operated either CONIT or any of the four connected retrieval systems, performed searches on 20 different topics using CONIT with no assistance other than that provided by CONIT itself (except to recover from computerlsoftware bugs). These same users also performed searches on the same topics with the help of human expert intermediaries who searched using the retrieval systems directly. Sometimes CONIT and sometimes the human expert were clearly superior in terms of such parameters as recall and search time. In general, however, users searching alone with CONIT achieved somewhat higher online recall at the expense of longer session times. We conclude that advanced experimental intermediary techniques are now capable of providing search assistance whose effectiveness at least approximates that of human intermediaries in some contexts. Also analyzed is the cost effectlveness of current intermediary systems. Finally, consideration is given to the prospects for much more advanced systems which would perform such functions as automatic database selection and the simulation of human experts, and thereby make information retrieval more effective for all classes of users.
A note on Koornwinder's polynomials with weight function (1−x)α(1+x)β+Mδ(x+1)+Nδ(x−1)

We derive the distribution and three-term recurrence relation for the Koornwinder [2] polynomials with weight function shown above using the method developed in our paper [3]. We are able to obtain explicit expressions for the linear functional in terms of the coefficients of the three-term recurrence relation for the Jacobi polynomials and we obtain the distribution using a more direct approach.
Ridge regression estimator comparisons using pitman's measure of closeness

The theory presented in Mason, Keating, Sen and Blaylock (1990) and applied to the comparison of ridge regression estimators using Pitman's measure of closeness is illustrated on two data sets, one that contains a strong collinearity and one that is nearly orthogonal. The regions of preference for the ridge regression estimator over the least squares estimator are established and shown to be dependent on the eigenvalues and eigenvectors of the correlation matrix of the predictor variables, the unknown coefficient vector, the error variance, and the value of the biasing constant in the ridge estimator.
The relationship between stochastic and temporal dominance under an accuracy set

The method of replicated paired-comparisons was utilized to obtain estimates of response consistency and mean response latency for both preferential choices for two outcome gambles and judgmental choices of the riskiness of these bets. The results indicate that under an accuracy set stochastically-dominant choices have a shorter mean latency than stochastically-non-dominant choices. The implications of this result for mathematical models of response latency are considered.
090 Extracellular Matrix Regulation and Dermal Repair in Burn Wound

To better understand the mechanisms of dermal restoration in burn wound we examined the mRNA expressions, using a porcine secondary-degree burn wound model, of major dermal matrices including type I, III collagens and elastin, basement membrane components of collagen IV and laminins, regulatory Matrix Metalloproteinase MMP 1 and MMP 9, as well as growth factors of bFGF, CTGF, TGFβ, and VEGF. Fresh skin burn wound samples from six pigs were collected at days 0, 1, 4, 7, 10, 14, and 21. Semiquantitative Reverse Transcription and Polymerase Chain Reactions (RT-PCR) were used with gene-specific primers. RT-PCR products were run on ethidium bromide gel and analyzed under UV light with Bio-Rad Gel Document 2000 system. One-way analysis of variance was used for statistical analysis. The results showed:'1) There were increases of all dermal extracellular matrices and growth factors tested; 2) A significant increase of type IV collagen occurred the earliest, while expressions of type I collagen and elastin increased at the latest; 3) A dramatic induction of MMP 1 and MMP 9 was observed shortly after wounding, which lasted through entire experiment; 4) The increased expression of VEGF, which is critical to angiogenesis, occurred early with peak at days 1 and 4, respectively. The expression pattern of bFGF, which has strong promoting effects on both endothelial cells and fibroblasts, is similar to that of VEGF; 5) For growth factors important for matrix deposition, both TGF beta 1 and 3 expressions increased gradually with sustained high level during entire experiment. The expression of CTGF, which is important in matrix production and remodeling, increased in later stage. This study showed the correlation between growth factor expression and dermal matrix deposition, which may have implications in developing strategies to improve burn wound healing. This study was supported by grants from DOD/DARPA and the Dermatology Foundation of South Florida.
On Groups in Which Every Subgroup of Infinite Rank Is Subnormal of Bounded Defect

Abstract A special case of the main result is as follows: Let G be a locally (soluble-by-finite) group of infinite rank in which every subgroup of infinite rank is subnormal of defect at most d. Then G is nilpotent of class bounded in terms of d only. This extends a famous theorem of Roseblade and holds, more generally, for groups G that belong to the class &#x1d51b; introduced by Cernikov. It is also shown that G is a Dedekind group if d = 1.
Diversity of Archaeosine Synthesis in Crenarchaeota

Archaeosine (G+) is found at position 15 of many archaeal tRNAs. In Euryarchaeota, the G+ precursor, 7-cyano-7-deazaguanine (preQ0), is inserted into tRNA by tRNA-guanine transglycosylase (arcTGT) ...
Quantitative multiparametric two-photon imaging of tissues

The characterization of engineered tissue development has been performed via invasive means that have limited abilities to capture the dynamic nature of the interactions and changes that occur. Optical spectroscopic imaging could serve as a non-invasive approach to overcome this limitation. Implemented on a two-photon microscopy platform, spectroscopic imaging can provide information on the biochemistry, structure and organization of the cellular, extracellular matrix and biomaterial scaffolds that make up engineered tissues. We find that distinct spectral shifts characterize the secondary structure of biomaterial silk scaffolds, as well as the differentiation status of epithelial and mesenchymal stem cells. The knowledge we gain is relevant not only for the optimization of tissue regeneration, but also for disease diagnostic and therapeutic applications.
Observation of the temporal Talbot effect for entangled photons

We demonstrate the generation of two-photon correlation trains based on spectral filtering of broadband biphotons and for the first time verify the temporal Talbot effect for entangled photons.
A principal component analysis of sulfur concentrations in the Western United States

Abstract Data from a 40 site network of air samplers in the western United States were used in a principal components analysis to obtain spatial patterns of the inter-site correlations of sulfur concentrations. After rotation of the initial eigenvectors, two large regions were identified which accounted for 33.1% of the variance in the data. Three other smaller regions were identified which also had significant variance. The first eigenvector included all sites in the southern part of the network and was attributed to copper smelter emissions in Arizona and New Mexico. The second eigenvector included sites in the northern great plains and was attributed to episodic incursions of sulfur from the east. The third, fourth and fifth eigenvectors were attributed to locally important conditions.
The Equilibrium Energy Spectrum of Randomly Forced Two-Dimensional Turbulence

Abstract From a statistical mechanical treatment of an ensemble of randomly forced two-dimensional flows of a viscous fluid, we derive two independent integral constraints on the form of the equilibrium energy spectrum. With a single hypothesis about the shape-preserving properties of the spectrum, those constraints determine the spectrum to within the value of a single universal dimensionless constant. In all other respects the argument is deductive and does not depend on closure approximations or hypotheses about the process of nonlinear energy transfer. The spectrum exhibits minus third-power dependence for, small scales, but minus first-power dependence for large scales. It is in good agreement with the results of detailed numerical integrations of the Navier-Stokes equations.
Optically inhibited collisional dephasing

We have performed a photon-echo experiment on the 555.6-nm intercombination line of atomic Yb vapor which demonstrates that an intense laser field acts to inhibit the dephasing resulting from velocity-changing collisions. This finding implies that the optical Bloch equations, which assume that relaxation is independent of the strength of the driving field, cannot correctly describe the behavior of gas-phase samples in all regimes.
Biochemical genetic analysis of 2',3'-dideoxyadenosine metabolism in human T lymphocytes.

Summary 2′,3′-dideoxyadenosine (ddAdo) has been shown to inhibit the infection of cultured human T lymphoblasts with the human immunodeficiency virus-1 (HIV-1). However, the pathways of ddAdo metabolism in T lymphocytes have not been well defined. We have studied the uptake and degradation of ddAdo in human CEM T lymphoblasts, in mutant CEM T cells deficient in adenosine kinase or deoxycytidine kinase, and in normal lymphocytes and monocytes. The results indicate that ddAdo may be phosphorylated in T cells by several different enzymes, although deoxycytidine kinase predominates. However, 99% of the ddAMP formed is deaminated by AMP deaminase and subsequently dephosphorylated. Thus, the ability of ddAdo to prevent HIV-1 infection may be limited in cells with high AMP deaminase activity.
Inadvertent positioning of pacemaker leads in the pericardium.

A patient had a dual chamber pacemaker with endocardial leads implanted chronically. The lead position on chest X ray and the ECG pattern indicated lead malposition, but a CT scan and transesophageal echocardiography were nondiagnostic. Venography indicated that both leads were in the mediastinal and pericardial space. (PACE 2003; 26:2039–2041)
Catalyst-controlled inverse-electron-demand hetero-Diels-Alder reactions in the enantio- and diastereoselective synthesis of iridoid natural products.

Iridoid natural products 1−4 are accessed stereoselectively by means of tridentate (Schiff base)Cr(III)-catalyzed hetero-Diels−Alder reactions between ethyl vinyl ether and enantioenriched 5-methyl-1-cyclopentene-1-carboxaldehyde. An efficient route to the aldehyde from citronellal is afforded by the ring-closing metathesis reaction.
WOMEN AND THE FALSE PROMISE OF MICROENTERPRISE

Since the 1980s, microenterprise development programs have proliferated in the United States, where they are widely praised as strategies for economic development and poverty alleviation, especially for low-income women and welfare mothers. Based on research in a highly respected urban center for women, this article argues that microenterprise development is more detrimental and problematic than it is purported to be. Two reasons are isolated. First, gender constraints mean women tend to choose small-scale, undercapitalized, and barely profitable “pink-collar” businesses, largely home-based operations based on work women are already doing as part of their gender-specific role. Second, microenterprise training programs reinforce this business segregation by discounting the sociocultural conditions women bring with them to business and instead emphasizing the personal growth of individuals. The result is that women are encouraged to maintain their economic vulnerability and social peripheralization rather t...
Computational study of opposed-force-flow flame spread across propanol pools

Abstract Two-dimensional flame-spread across sub-flash-point propanol pools in opposed-forced airflow is investigated numerically for normal and zero gravities with finite-rate, one-step chemical kinetics, variable properties, and an adaptive finite-difference gridding scheme. Effects of air speed, liquid depth, and gravity on the characteristics of the flame-spread are examined with correct initial profiles for the gas-phase velocity and the mass-fraction of fuel vapor before ignition. Some of the results are as follows: (1) 10-mm pools are deep enough to examine flame-spread rates on deep pools in the uniform regime and pulsation frequencies on deep pools in the pulsating regime; (2) the pseudo-uniform regime is found only in deep pools and not in shallow pools; (3) the effect of opposed-forced airflow on the flame-spread rate is different, depending on the regime for T 0 , where T 0 denotes the initial pool temperature. Effects of pool depth on the liquid phase are also investigated: there is only a surface-tension-driven flow in the liquid phase of shallow pools. Finally, the flame-spread regime is displayed as a function of initial pool temperature, air speed, pool depth, and gravity.
Modulation and fast decay of photon-echos in ruby

Abstract Observations are reported on concentration effects, Cr-Al modulation and fast decay in photon-echo relaxation measurements in ruby, performed by the direct echo-signal versus time method.
A meta-analysis comparing tree growth in monocultures and mixed plantations

Ample evidence has indicated that mixed tree plantations are the most appropriate option for providing a broad range of goods and environmental services, but still debate continues about whether mixed plantations can achieve greater productivity than can monocultures. In this study, a meta-analysis of published studies was performed to synthesize results of growth in mixed plantations and monocultures across differing regions and species. A total of 14 studies representing 46 tree species from tropical and temperate ecosystems were included to test three hypotheses: stand composition affects tree height growth rate; stand composition affects tree diameter growth rate; and presence of nitrogen-fixing tree species in mixed tree plantations affects the diameter growth rate of non-fixing species. It was found that mixed plantations did not have larger height growth rates, but that the diameter growth rate was higher in mixed plantations, with a moderate but statistically significant effect size. Nitrogen-fixing tree species had a positive effect on the diameter growth rate of non-fixing species, with a large and statistically significant effect size. This study suggests that mixing tree species generally increases plantation growth rate. Furthermore, mixed tree plantations can play an important role in satisfying economic needs by shortening rotations yet adding other ecological benefits. Silviculturalists should adopt mixed plantations more widely across degraded landscapes, as well as nitrogen-fixing tree species to maximize positive interactions in mixed plantations.
High-frequency plant regeneration from seed-derived callus cultures of Kentucky bluegrass ( Poa pratensis L.)

Shoot regeneration from seed-derived callus cultures of Kentucky bluegrass (Poa pratensis L.) was tested on MS basal medium supplemented with four different growth regulators. Regeneration frequencies for medium supplemented with 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 60 μM 4amino-3, 5,6-picolinic acid (picloram), or 30 μM 3,6dichloro-o-anisic acid (dicamba) ranged from 0.4 to 4%. Medium supplemented with 30 μM dicamba plus 10 μM 6-benzylaminopurine (BA) resulted in regeneration of shoots from 20% of the calli tested. Higher rates of growth regulators (60 or 90 μM dicamba, 20 μM BA) resulted in regeneration of shoots from 45% of calli of the cultivar ‘Baron’. In a subsequent study, the response of 12 North American cultivars grown on these media was cultivar-specific, with mean frequencies of regeneration ranging from 4% to 40%.
Thyroid neoplasia in children

In 1995, the incidence of childhood thyroid cancer in England and Wales was only 0.5 cases per million children per year. Papillary cancers in younger children were histologically distinct from tumors in older individuals. The incidence of thyroid cancer in the vicinity of Chernobyl increased by 62 times within 5 years of the nuclear explosion. Mutations of the RET protooncogene (a growth factor receptor) occur in nearly all familial medullary thyroid carcinomas and may be used for family screening. RET is involved in chromosomal rearrangements in a majority of childhood papillary thyroid cancers. Fine-needle aspiration biopsy identifies the childhood thyroid nodules that are at greatest risk for cancer. It should be noted, however, that approximately 2% of aspirates are falsely negative. The adequacy of unilateral surgery for papillary thyroid cancers is controversial. Aggressive surgery for persistent medullary carcinoma produces remission in one third of patients. Novel radionuclide techniques are useful in detecting and treating metastatic medullary carcinoma.
Simulation of an absorption heat pump solar heating and cooling system

Abstract An absorption heat pump (AHP) is a heat driven heat pump utilizing the absorption process. A continuous, liquid absorbent AHP with chemical storage is modeled using mass and energy balances and assuming mass transfer equilibrium. This model is used with the TRNSYS program [5] to simulate the performance of an AHP in a residential solar-driven heating and cooling system. The effects of collector area for an AHP using the NaSCNNH 3 chemical system are investigated for the Columbia, MO, Madison, WI, and Fort Worth, TX climates. The AHP system is compared to a conventional solar heating and cooling system and the effects of heat exchanger effectiveness, storage mass, additional thermal capacitance and alternative control strategies are studied for the Columbia climate.
Optical pumping experiments on next-generation light sources

Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at the redistribution of radiation. However, the possibilities for optical lasers end for plasmas with n{sub e}>10{sup 22}cm{sup -3} as light propagation is severely altered by the plasma. The construction of the Tesla Test Facility(TTF) at DESY(Deutsche Elektronen-Synchrotron), a short pulse tunable free electron laser in the vacuum-ultraviolet and soft X-ray regime (VUV FEL), based on the SASE(self amplified spontaneous emission) process, will provide a major advance in the capability for dense plasma-related research. This source will provide 10{sup 13} photons in a 200 fs duration pulse that is tunable from {approx} 6nm to 100nm. Since an VUV FEL will not have the limitation associated with optical lasers the entire field of high density plasmas kinetics in laser produced plasma will then be available to study with tunable source. Thus, one will be able to use this and other FEL x-ray sources to pump individual transitions creating enhanced population in the excited states that can easily be monitored. We show two case studies illuminating different aspects of plasmamore » spectroscopy.« less
THE ULTRASTRUCTURE OF LICHENS. II. CLADONIA CRISTATELLA: THE LICHEN AND ITS ISOLATED SYMBIONTS1,2,3

SUMMARY A Comparative Study Was Made Of The Fine Structure of Cladonia Cristatella and its algal Symbiont Trebouxia Erici in their lichenized and cultured ( nonlichenized) states. Pyrenoglobuli were produced by the alga in the symbiotic and free conditions. Starch was formed during hydrated conditions. Pyrenoglobbuli migrated to the outer parts of the pyrenoid only during dry periods. Dictyosomes and eyespots were observed for the first time in Trebouxia. The pyrenoid divided by fragmentation. Ellipsoidal bodies were common in the hyphae of the lichenized fungus and absent in cultured hyphae, except for 1 colony which had been induced to form pycnidia. The ellipsoidal bodies were associated closely with the internal membrane system of the mycobiont. Haustoria seemed to penetrate the algal cells by enzymatic digestion. Intrahyphal hyphae were common.
Polymer surface modification for the attachment of bioactive compounds

This paper reviews recent advances in the covalent attachment of bioactive compounds to functionalized polymer surfaces including relevant techniques in polymer surface modification such as wet chemical, organosilanization, ionized gas treatments, and UV irradiation. Methods of analysis of biofunctionalized polymer surfaces, including spectral methods (X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, atomic force microscopy, and others) as well as non-spectral methods (contact angle, dye assays, biological assays, and zeta potential) are also considered. State-of-the-art techniques in covalent conjugation of bioactive compounds to the modified surfaces, such as usage of hydrophilic, bifunctional, and/or branched spacer molecules, are presented. Relevant bioconjugation reagents and chemistries are described and tabulated. Recently reported applications in areas such as biomedicine, biosensors, enzyme reactors, and textiles, all of which utilize a common set of surface bioconjugation techniques to address these diverse needs, are discussed. Finally, challenges to this emerging field of research are critically evaluated.