cssi/SciSciGPT-SciSciNet huggingface dataset:
Synchronization of Coupled Harmonic Oscillators by Time-Dependent Topology Switching

Abstract This paper studies the approach of taking network topology as a control variable for the analysis of coupled harmonic oscillators. We particularly consider the setting where the local control inputs of individual oscillators are governed by their relative positions. Based on the known results in the theory of stability of switched linear systems, we propose a time-dependent topology-switching algorithm that enables the oscillators to asymptotically achieve synchronization. The main advantages of the proposed method, with respect to the prior work, are two-fold: we allow the coupling strength to be negative; and we do not constrain the magnitude of positive coupling strength. Simulation results are provided to verify the effectiveness of the algorithm.
Contemporary strategies for enhancing nitrogen retention and mitigating nitrous oxide emission in agricultural soils: present and future

The increasing food demand and deteriorating climate change require improvement in current strategies for enhancing nitrogen (N) retention and mitigating nitrous oxide (N2O) emission in agricultural soils. This paper has discussed and compared the mechanisms, effects and affecting factors of major contemporary strategies, including soil amendment with biochar, biological nitrification inhibition (BNI) and applications of synthetic nitrification inhibitor (NI), urease inhibitor (UI), hydrogel and slow-/controlled-release fertilizer (SRF/CRF). Among these strategies, soil amendment with biochar seems to be the most promising, considering its demonstrated effectiveness and sustainable nature. Despite the large number of biochar-relevant studies in the recent years, the data have not been systematically utilized. A database model has been proposed in this review to link the production, properties and performance of biochar and delve into the valuable information scattered in current and future biochar studies. At the same time, the other strategies should also be continuously studied for improvement. NIs and UIs need to be more stable and lasting; hydrogels and SRFs/CRFs have to be more environmentally friendly and economically sound; BNI deserves broader investigations and its future applications can be more widespread. Future studies may also explore strategic combinations of two or more contemporary strategies. More long-term studies should be conducted to improve the evaluation of benefits and flaws of these strategies.
α-Helix-Mimetic Foldamers for Targeting HIV-1 TAR RNA

An oligopyridylamide-based foldamer approach has been employed to target HIV TAR RNA-TAT assembly as a model system to study RNA-protein interactions. The oligopyridylamide scaffold adopts a constrained conformation which presents surface functionalities at distinct spatial locations and mimic the chemical features of the secondary structure of proteins. We have designed a library of oligopyridylamides containing diverse surface functionalities which mimic the side chain residues of the TAT protein domain. The interaction of TAR RNA and TAT plays a pivotal role in facilitating HIV replication. The library was screened using various fluorescent based assays to identify antagonists of the TAR RNA-TAT complex. A tricationic oligopyridylamide ADH-19, possessed the highest affinity towards TAR and efficiently inhibited the TAR RNA-TAT interaction with apparent Kd of 4.1±1.0 μm. Spectroscopic studies demonstrated that ADH-19 interacts with the bulge and the lower bulge regions of TAR RNA, the domains important for TAT interaction. ADH-19 demonstrated appreciable in vivo efficacy (IC50 =25±1 μm) by rescuing TZM-bl cells infected with the pseudovirus HIV-1HXB-2.
Asymmetric δ-Lactam Synthesis with a Monomeric Streptavidin Artificial Metalloenzyme

Reliable design of artificial metalloenzymes (ArMs) to access transformations not observed in nature remains a long-standing and important challenge. We report that a monomeric streptavidin (mSav) Rh(III) ArM permits asymmetric synthesis of α,β-unsaturated-δ-lactams via a tandem C-H activation and [4+2] annulation reaction. These products are readily derivatized to enantioenriched piperidines, the most common N-heterocycle found in FDA approved pharmaceuticals. Desired δ-lactams are achieved in yields as high as 99% and enantiomeric excess of 97% under aqueous conditions at room temperature. Embedding a Rh cyclopentadienyl (Cp*) catalyst in the active site of mSav results in improved stereocontrol and a 7-fold enhancement in reactivity relative to the isolated biotinylated Rh(III) cofactor. In addition, mSav-Rh outperforms its well-established tetrameric forms, displaying 11-33 times more reactivity.
Caribeño or mexicano , profesionista or albañil ? Mexican listeners’ evaluations of /s/ aspiration and maintenance in Mexican and Puerto Rican voices

Mexican Spanish is generally recognized as a conservative variety that maintains syllablefinal /s/, while Puerto Rican Spanish consistently weakens it. To explore what social properties are indexed by coda /s/ variants and whether these variants alone can alter evaluations of speaker origin, 75 Mexican listeners participated in a matched-guise test. They listened to recordings of five Mexican and Puerto Rican Spanish speakers spliced to include only coda [s] or coda [h], evaluating speakers on a scale of social properties and identifying their perceived place of origin. Mixed effects models fitted to 6,750 evaluations demonstrate that [s] is associated with various measures of status, including intelligence, work ethic, confidence, and snobbishness. However, these evaluations are conditioned by listeners' stereotypes and regional expectations, as Mexicans were evaluated as speaking better Spanish when presented with [s] and Puerto Ricans as speaking better Spanish with [h]. Finally, listeners evaluated Puerto Rican voices as significantly more Mexican given coda [s] and Mexican voices as significantly more Caribbean given coda [h], with the most drastic shift for Mexican speakers. The paper concludes that manipulating a single salient variable (/s/) is sufficient to override other linguistic features, which play a much more limited role in social identification and evaluation.
Optimizing the performance of reactive molecular dynamics simulations for many-core architectures

Reactive molecular dynamics simulations are computationally demanding. Reaching spatial and temporal scales where interesting scientific phenomena can be observed requires efficient and scalable im...
Experimental and Molecular Dynamics Simulation Study of the Effects of Lignin Dimers on the Gel-to-Fluid Phase Transition in DPPC Bilayers

High resolution differential scanning calorimetry (DSC) and molecular dynamics (MD) simulations were used to investigate the effect of three lignin dimers on the gel to fluid phase transition in DPPC lipid bilayers. The goal of this research is to begin to understand the partitioning of model lignin dimers into lipid bilayers and its effects on the gel to fluid transition temperature (Tm). The long-term objective is to establish structure-function relationships for well-defined lignin derivatives at biologically relevant surfaces. This work uses a newly synthesized guiacylglycerol guaiacol ester with a hydroxypropenyl (HOC3H4-) group resembling natural lignin (GG dimer), compared with a truncated GG dimer without the HOC3H4- and benzyl-modified GG dimers. The DSC results show that the dimer most like natural lignin (with a hydroxypropenyl tail) has log K = 2.72 ± 0.05, and MD simulations show that it associates with the headgroups of the lipid but does not penetrate strongly into the interior of the bilayer. Therefore, this dimer has little effect on the Tm value. In contrast, the truncated dimer, which has been used as a representative GG dimer in prior studies, partitions into the bilayer, as seen in MD simulations, and shifts Tm because of its increased lipophilicity (DSC log K = 3.45 ± 0.20). Similarly, modification of the natural GG dimer by benzylation of the phenol makes it lipophilic (DSC log K = 3.38 ± 0.28), causing it to partition into the bilayer, as seen in MD simulations and shift Tm. In MD, we capture the transition from gel to fluid phase by defining and analyzing a normalized deuterium order parameter averaged over all carbon atoms located in the middle of the lipid tails. In this way, the phase transition can be clearly observed and, importantly, MD results show the same trend of transition temperature shifts as the DSC results. Furthermore, we compare partition coefficients estimated from free energy profiles calculated in MD to those obtained from experiment and they are in qualitative agreement. The success at predicting the structural effects of lignin dimers on lipid bilayers suggests that MD simulations can be used in the future to screen the interactions of lignin oligomers and their derivatives with lipid bilayers.
Relationships Between p -values and Pearson Correlation Coefficients, Type 1 Errors and Effect Size Errors, Under a True Null Hypothesis

The American Statistical Association (ASA) published a statement in 2016 in The American Statistician for “researchers, practitioners and science writers who are not primarily statisticians” on the proper use and interpretation of p-values. Three years later, the ASA acknowledged that telling researchers what not to do with p-values was insufficient. Consequently, 3 years later an open access, special issue appeared with 43 papers proposing various novel and sophisticated alternatives to classical p-values for use with scientific methods in the twenty-first century. In the opening remarks, the editors stated that “no p-value can reveal the plausibility, presence, truth, or importance of an association or effect” and banned statistical significance: “don’t say it, don’t use it.” This paper questions both statements with a simulated data study. It is shown that p-values are strongly related to correlation coefficients under a true null hypothesis; hence, can reveal the “importance of an association or effect.” Furthermore, it demonstrates why a cut point for statistical significance is still a viable, ancillary tool for assessing the substantive significance of statistical effects with small sample sizes (n < 1000).
The Neurological Examination Improves Cranial Accelerometry Large Vessel Occlusion Prediction Accuracy

We combined cranial accelerometry, a device-based approach to large vessel occlusion (LVO) prediction, with neurological examination findings to determine if this improves diagnostic accuracy compared to either alone. Cranial accelerometry recordings and NIHSS scores were obtained during stroke codes and thrombectomy transfers at an academic medical center using convenience sampling. The reference standard was discharge diagnosis of LVO stroke. We compared accuracy statistics between machine learning models trained using cranial accelerometry alone, with asymmetric arm weakness added, with NIHSS scores added, and retrospective examination only LVO prediction scales. An exploratory analysis required asymmetric arm weakness prior to model training or scale testing. Of 68 patients, there were 23 LVO strokes. Cranial accelerometry was 65% sensitive (95% CI 43–84%) and 87% specific (95% CI 73–95%). Adding asymmetric arm weakness increased specificity to 91% (95% CI 79–98%). Adding asymmetric arm weakness and the NIHSS increased sensitivity to 74% (95% CI 52–90%) and decreased specificity to 89% (95% CI 76–96%). LVO prediction scales had wide sensitivity and specificity ranges. The exploratory analysis improved sensitivity to 91% (95% CI 72–99%) and specificity to 93% (95% CI 92–99%) with only three false positives and two false negatives. Cranial accelerometry models are improved by various additions of asymmetric arm weakness and the NIHSS. An exploratory analysis requiring asymmetric arm weakness prior to cranial accelerometry model training minimized false positives and negatives.
Asparagine-linked carbohydrate chains of inducible rat parotid proline-rich glycoprotein contain terminalβ-linked N-acetylgalactosamine

Rats treated with daily injection of DL-isoproterenol for 10 consecutive days (25 mg kg1 body weight) showed marked induction of a proline-rich glycoprotein (GPRP) of 220 kDa. Proteinase K digestion of GPRP produced a homogeneous glycopeptide with an average chemical composition as follows (residues per mol): Pro4, Glx3, Asx2, Gly1, His1, Thr1, Arg1, GlcNAc5, GalNac1, Man3, Gal2–3, and Fuc1. The structural analysis of the asparagine-linked carbohydrate unit was performed by methylation, periodate oxidation and enzymatic degradation. Methylation studies indicated that the three mannosyl residues were substituted at 1,2-, 1,2,4-, and 1,3,6-positions. Fucose, N-acetylgalactosamine, 1.5 residues of galactose and 0.35 residues of N-acetylglucosamine were terminally located and one galactose residue was 1,4-substituted. Approximately four of the 5 N-acetylglucosamine residues were substituted at 1,4-position and approximately 1 residue of N-acetylglucosamine was substituted at 1,4,6-positions. Periodate oxidation studies and exoglycosidase results were consistent with the methylation data. Based on the results of Smith degradation, methylation and sequential exoglycosidase digestions a triantennary oligosaccharide structure having terminal N-acetylgalactosamine in one of the branches is proposed for the major Asn-linked carbohydrate moiety of GPRP.
Peripheral Guanylate Cyclase-C modulation of corticolimbic activation and corticotropin-releasing factor signaling in a rat model of stress-induced colonic hypersensitivity

Background Psychological stress is a risk factor for irritable bowel syndrome, a functional gastrointestinal pain disorder featuring abnormal brain-gut connectivity. The guanylate cyclase-C (GC-C) agonist linaclotide has been shown to relieve abdominal pain in IBS-C and exhibits antinociceptive effects in rodent models of post-inflammatory visceral hypersensitivity. However, the role GC-C signaling plays in psychological stress-induced visceral hypersensitivity is unknown. Here, we test the hypothesis that GC-C agonism reverses stress-induced colonic hypersensitivity via inhibition of nociceptive afferent signaling resulting in normalization of stress-altered corticotropin-releasing factor (CRF) expression in brain regions involved in pain perception and modulation. Methods Adult female rats were exposed to water avoidance stress or sham stress for 10 days, and the effects of linaclotide on stress-induced changes in colonic sensitivity, corticolimbic phospho-extracellular signal-regulated kinase (pERK), and CRF expression were measured using a combination of behavioral assessments, immunohistochemistry, and qRT-PCR. Key results Stressed rats exhibited colonic hypersensitivity and elevated corticolimbic pERK on day 11, which was inhibited by linaclotide. qRT-PCR analysis revealed dysregulated CRF expression in the medial prefrontal cortex, paraventricular nucleus of the hypothalamus, and central nucleus of the amygdala on day 28. Dysregulated CRF expression was not affected by linaclotide treatment. Conclusions and inferences Our results demonstrate that exposure to repeated stress induces chronic colonic hypersensitivity in conjunction with altered corticolimbic activation and CRF expression. GC-C agonism attenuated stress-induced colonic hypersensitivity and ERK phosphorylation, but had no effect on CRF expression, suggesting the analgesic effects of linaclotide occur independent of stress-driven CRF gene expression in corticolimbic circuitry.
Algorithm Awareness in Repeated Marketing Campaigns: A Field Experiment

In this paper, we study how consumers respond to repeated marketing campaigns driven by algorithms and how the responses vary across different algorithms. To investigate it, we collaborate with a U.S. food delivery company and conduct a field experiment where targeted coupons are sent by applying the same algorithms repeatedly. Our results show that algorithms utilizing more information perform better than simpler algorithms, and this difference only exists when the consumers have already been treated by the same algorithm-driven policy a few times. By exploring the variation in the purchase patterns, we show that those differences arise because advanced algorithms reduce the level of learning and strategic behaviors against the rules. This result also suggests that consumers may have some level of algorithm awareness, especially when algorithms are easy to learn, and are forward-looking enough to play strategically against the policies powered by those algorithms.
Understanding China's Legal Gamesmanship in the Rules-Based Global Order

In the contemporary era of international relations, some government officials and non-government observers have posited that the People's Republic of China (PRC) is a rising power that challenges the existing, rules-based global order. But it would be an oversimplification to argue that the PRC always seeks to undermine the rules-based component of that order. Therefore, this chapter examines the PRC’s approach to the rules-based component of the global order more closely, and reaches a more nuanced conclusion. At the outset, this chapter assumes that the PRC is competing with other states within a complicated international system composed of complex relationships. Yet while international conflict is undesirable and international cooperation can be appealing, sandwiched in between the two is international competition, which is not inherently bad or evil. In the competitive aspect of relationships between states, individual states can and will use a range of tactics to further their own interests, to include tactics involving law and rulesets. Over the past two decades, American legal scholars coined the portmanteau “lawfare” and Chinese military strategists have developed the concept of “legal warfare,” both of which are defined as “using law as a weapon.” These labels, however, might be too warlike, provocative, or under inclusive in nature to capture what the PRC is actually doing. If a primary goal of any competition is to win, then one must consider what might be the best way to characterize tactics employed by players for the purpose of winning. In the competitive context of sports and leisure games, particular behavior by participants could be labelled as “gamesmanship,” which has been defined as “the art of winning games without actually cheating.” Therefore, in the context of the PRC and its actions in relation to the existing rules-based global order, one must consider how the PRC is utilizing various “legal gamesmanship” tactics in different situations for a competitive advantage. This chapter argues that the PRC seeks to shape and reshape the normative aspects of the rules-based component of the global order, while also attempting to leverage the instrumental aspects of that same component. To support this argument, this chapter explores several of the common “legal gamesmanship” tactics employed by the PRC, offers specific examples of those employed tactics, and analyzes the purposes of those tactics. While the PRC’s approach to international law is more nuanced than arguing that the PRC always seeks to undermine the rules-based component of the global order, what the PRC is seeking to accomplish remains troubling nonetheless. Thus, this chapter concludes by showing why those tactics should be concerning to other states, and recommends a number of counter-tactics for other states to employ in order to counter the PRC’s “legal gamesmanship.”
Specific phenotypic, genomic, and fitness evolutionary trajectories toward antibiotic resistance induced by pesticide co-stressors in Escherichia coli

To explore how co-occurring non-antibiotic environmental stressors affect evolutionary trajectories toward antibiotic resistance, we exposed susceptible Escherichia coli K-12 populations to environmentally relevant levels of pesticides and streptomycin for 500 generations. The coexposure substantially changed the phenotypic, genotypic, and fitness evolution trajectories, resulting in much stronger streptomycin resistance (>15-fold increase) of the populations. Antibiotic target modification mutations in rpsL and rsmG, which emerged and dominated at late stages of evolution, conferred the strong resistance even with less than 1% abundance, while the off-target mutations in nuoG, nuoL, glnE, and yaiW dominated at early stages only led to mild resistance (2.5 - 6-fold increase). Moreover, the strongly resistant mutants exhibited lower fitness costs even without the selective pressure and had lower minimal selection concentrations than the mildly resistant ones. Removal of the selective pressure did not reverse the strong resistance of coexposed populations at a later evolutionary stage. The findings suggest higher risks of the selection and propagation of strong antibiotic resistance in environments potentially impacted by antibiotics and pesticides.
J M Keynes's Evidential Weight of the Argument, V(A/H),Which Applies to Arguments, is Different from the Weight of the Evidence, W, Which is a Measure of the Completeness of the Information, Data, Evidence, or Knowledge in the Premises, H

Keynes’s V(a/h) relation, first presented on p.72 of chapter 6 of the A Treatise on Probability (1921), represents the Evidential Weight of the Argument from h to a. H and a are related to each other and can’t be separated. V relates two sets of propositions, a and h. H is the premises and a is the conclusion. It is not possible to talk about h separately from a or a separately from h when using V. Keynes introduced w, the weight of the evidence, in Chapter 26 of the A Treatise on Probability in preparation for the construction of his conventional coefficient of weight and risk, c. C is not a probability. C is a decision weight. It represents the first use of and creation of a decision weight in history. W is defined by Keynes as a measure of the completeness of the relevant evidence, knowledge or data that is contained in the premises, h. It is a measure of the completeness of the evidence contained in the premises. It has nothing to do with V(a/h). It was introduced in the first paragraph of chapter 6 on p.71, before Keynes introduced his V(a/h) relation on p.72. The first paragraph deals exclusively with the premises containing the evidence. It does not deal with V. It is impossible to substitute V for w since they are different. V and w can’t be compared because V represents the logical relation between h and a, while w is a mathematical variable, normalized on the unit interval [0,1], that represents the completeness of the amount of available evidence, data, or knowledge, represented by h. Keynes never normalized V on the unit interval [0,1]. Keynes only normalized w on the unit interval [0,1]. The failure to understand the differences between V(a/h) and w, which is a measure of the strength of h, leads to confusion and error among heterodox economists, Post Keynesians, and economists associated with Cambridge University, England.
FLAME-in-NeRF : Neural control of Radiance Fields for Free View Face Animation

This paper presents a neural rendering method for controllable portrait video synthesis. Recent advances in volumetric neural rendering, such as neural radiance fields (NeRF), has enabled the photorealistic novel view synthesis of static scenes with impressive results. However, modeling dynamic and controllable objects as part of a scene with such scene representations is still challenging. In this work, we design a system that enables both novel view synthesis for portrait video, including the human subject and the scene background, and explicit control of the facial expressions through a low-dimensional expression representation. We leverage the expression space of a 3D morphable face model (3DMM) to represent the distribution of human facial expressions, and use it to condition the NeRF volumetric function. Furthermore, we impose a spatial prior brought by 3DMM fitting to guide the network to learn disentangled control for scene appearance and facial actions. We demonstrate the effectiveness of our method on free view synthesis of portrait videos with expression controls. To train a scene, our method only requires a short video of a subject captured by a mobile device.
NeuroConstruct: 3D Reconstruction and Visualization of Neurites in Optical Microscopy Brain Images.

We introduce NeuroConstruct, a novel end-to-end application for the segmentation, registration, and visualization of brain volumes imaged using wide-field microscopy. NeuroConstruct offers a Segmentation Toolbox with various annotation helper functions that aid experts to effectively and precisely annotate micrometer resolution neurites. It also offers an automatic neurites segmentation using convolutional neuronal networks (CNN) trained by the Toolbox annotations and somas segmentation using thresholding. To visualize neurites in a given volume, NeuroConstruct offers a hybrid rendering by combining iso-surface rendering of high-confidence classified neurites, along with real-time rendering of raw volume using a 2D transfer function for voxel classification score vs. voxel intensity value. For a complete reconstruction of the 3D neurites, we introduce a Registration Toolbox that provides automatic coarse-to-fine alignment of serially sectioned samples. The quantitative and qualitative analysis show that NeuroConstruct outperforms the state-of-the-art in all design aspects. NeuroConstruct was developed as a collaboration between computer scientists and neuroscientists, with an application to the study of cholinergic neurons, which are severely affected in Alzheimers disease.
Automated Case Cancellation Review System Improves Systems-Based Practice

Accreditation Council for Graduate Medical Education (ACGME) core competencies of systems-based practice and practice-based learning and improvement are difficult to assess, as they are often not directly measurable or observable. Reviewing day-of-surgery cancellations could provide resident learning opportunities in these areas. An automated system to facilitate anesthesiology resident review of cancelled cases was implemented on the Preoperative Evaluation Clinic (PEC) rotation at the authors’ institution. This study aims to evaluate its impact on resident education. Residents on the PEC rotation during the 6 months preceding (n = 22) and following (n = 13) implementation in 2014 were surveyed about their experience performing cancelled case reviews in order to ascertain the effect of the intervention on their training. Significant changes were reported in the number of cases reviewed by each resident (p < 0.0001), perceived importance of review (p = 0.03), and ease of review (p = 0.03) after system implementation. There was also an increase in the proportion of cancelled cases reviewed from 17.3 % (34 of 196) to 95.6 % (194 of 203) (p < 0.0001). Non-significant trends were seen in perceived rotation effect on ACGME competencies, including systems-based practice. Several specific improvements to our clinical practice, including the creation of standardized guidelines, arose from these case reviews. Implementation of automated systems can improve compliance with educational goals by clarifying priorities and simplifying workflow. This system increased the number of cases reviewed by residents and the perceived importance of this review as a part of their educational experience.
On the effective distribution of knowledge represented by complementary graphs

Graph transformations are a very powerful tool for enabling formal description of the behavior of software systems. In most cases, however, they fail with regards to efficiency. This can be overcome by introducing parallel graph transformations. The concept of complementary graphs enables two things: the decomposition of a centralized graph into many cooperating subgraphs, and their parallel transformations. The rules of cooperation and implicit synchronization of knowledge, in this way represented, have been already defined in [8]. Such a model is very useful in an agent environment, where subgraphs represent the individual knowledge of particular agents; this knowledge may be partially replicated and exchanged between the agents. The basic problem is an initial graph distribution assuming the size criterion: the heuristic method proposed previously succeeds in 60% (i.e. 60% of subgraphs is consistent with the criterion). The method presented in this paper gives a 99.8% fit.
The therapeutic roller coaster : dilemmas in the treatment of childhood abuse survivors.

Survivors of severe childhood abuse often encounter profound difficulties. In addition to posttraumatic and dissociative symptomatology, abuse survivors frequently have characterologic problems, particularly regarding self-care and maintaining relationships. Backgrounds of abuse, abandonment, and betrayal are often recapitulated and reenacted in therapy, making the therapeutic experience arduous and confusing for therapists and patients. Efforts must be directed at building an adequate psychotherapeutic foundation before undertaking exploration and abreaction of past traumatic experiences. This discussion sets out a model for treatment of childhood abuse survivors, describing stages of treatment and suggesting interventions. Common treatment dilemmas or "traps" are discussed, with recommendations for their resolution.
Feasibility and Requirements for Dispersion Compensation in Coherent FOC

Despite many difficulties, a coherent Fiber Optical Communication (FOC) system is very attractive for long distance transmission because of its potentially enormous information bandwidth. Over long distance, fiber dispersion remains an important factor in limiting the information bandwidth. We discuss in this paper the feasibility of dispersion compensation using a novel optical modulation technique by which either one of the sidebands or the carrier can be suppressed.
Molecular sieve studies of interacting protein systems. X. Behavior of small zone profiles for reversibly self-associating solutes.

Abstract The behavior of small zone profiles for reversibly self-associating solutes has been investigated by computer simulation. Results indicate that the role played by axial dispersion in small zone profiles is dramatically different from that in corresponding large zone (plateau) experiments. The bimodal character of monomer-n-mer systems seen in derivative profiles from large zone experiments is greatly diminished and largely obscured by the greater dominance of axial dispersion effects. The effect of loading concentration has been investigated and the possible determination of equilibrium constants from variations in small zone elution time with loading concentration has been explored. It was found that even if the stoichiometry of reaction is already known, completely misleading information regarding the equilibrium constant is obtained from such procedures.
Ethically speaking: Bottoms up

Recently, I committed a faux pas. I'll tell you the story, and let you decide if I committed an ethical violation.
Mortality risk perceptions: a Bayesian reassessment.

This paper uses a Bayesian learning model to assess the respective influence of different risk measurements on mortality risk perceptions. People form risk beliefs using several sources of information, including the actual population mean death risk level, the discounted lost life expectancy, and the age-specific hazard rate considered by Benjamin and Dougan (1997). The appropriate criterion for judging the validity of risk perceptions is not the perfect information case, but rather whether people form their risk beliefs in a rational manner given a world of costly and limited risk information. Although the statistical results support the overall conclusion that the learning process is rational, the character of the learning process differs depending on the risk level. Risk-related variables are much better predictors of larger risks than of small risks, which reflects the role of information costs and the benefits of learning about larger risks.
Boundary force method for analyzing two-dimensional cracked plates

The Boundary Force Method (BFM) was formulated for the two-dimensional stress analysis of complex crack configurations. In this method, only the boundaries of the region of interest are modeled. The boundaries are divided into a finite number of straight-line segments, and at the center of each segment, concentrated forces and a moment are applied. This set of unknown forces and moments is calculated to satisfy the prescribed boundary conditions of the problem. The elasticity solution for the stress distribution due to concentrated forces and a moment applied at an arbitrary point in a cracked infinite plate are used as the fundamental solution. Thus, the crack need not be modeled as part of the boundary. The formulation of the BFM is described and the accuracy of the method is established by analyzing several crack configurations for which accepted stress-intensity factor solutions are known. The crack configurations investigated include mode I and mixed mode (mode I and II) problems. The results obtained are, in general, within + or - 0.5 percent of accurate numerical solutions. The versatility of the method is demonstrated through the analysis of complex crack configurations for which limited or no solutions are known.
TESTS OF GUSSET PLATE MODELS

The research program explored experimentally the means of gathering information about the stress distribution within gusset plates. Of the various joining methods, bolting was chosen. Two load conditions, one which corresponds to high chord forces and another which corresponds to high web forces were selected. Three modes of load transfer were investigated analytically and the case of load transfer through the boundary of the plates was also included in view of its importance in judging the applicability of photoelastic models. Of the available finite element methods two were compared. Small scale photoelastic models also were tested and compared to the steel models. From the comparison of the experimental results and the analytical data, it appears that large model tests are not likely to yield much more information than the proper combination of small model tests and modern numerical methods. The present data show that an assumed load transfer through the boundary of the plate will still not significantly change the internal stress distribution pattern in the plate.
Interleukin 6 modulates c-sis gene expression in cultured human endothelial cells

Abstract Human vascular endothelial cells secrete platelet-derived growth factor (PDGF)-like polypeptides which may mediate some of the vascular effects in the inflammatory process. We have demonstrated that IL-6 caused a significant increase in the mRNA level of the c-sis gene (PDGF B chain) in cultured human endothelial cells. IL-1α and IL-1β also increased c-sis mRNA transcripts after an extended incubation period and both cytokines acted synergistically with IL-6 in increasing c-sis expression. Tumor necrosis factor enhanced the accumulation of c-sis mRNA and interferon-γ decreased its level. In the inflammatory process specific cytokines can modulate c-sis expression in human endothelial cells. Their subsequent production of PDGF-like polypeptides could stimulate cell migration and proliferation, and cause the release of vascular inflammatory mediators.
Role of p38 MAP Kinase and Transforming Growth Factor-β Signaling in Transepithelial Migration of Invasive Bacterial Pathogens

Streptococcus pneumoniae and Haemophilus influenzae are human pathogens that often asymptomatically colonize the mucosal surface of the upper respiratory tract, but also occasionally cause invasive disease. The ability of these species to traverse the epithelium of the airway mucosa was modeled in vitro using polarized respiratory epithelial cells in culture. Migration across the epithelial barrier was preceded by loss of transepithelial resistance. Membrane products of S. pneumoniae that included lipoteichoic acid induced disruption of the epithelial barrier in a Toll-like receptor 2-dependent manner. This result correlates with a recent genetic study that associates increased TLR2 signaling with increased rates of invasive pneumococcal disease in humans. Loss of transepithelial resistance by the TLR2 ligand correlated with activation of p38 MAP kinase and transforming growth factor (TGF)-β signaling. Activation of p38 MAPK and TGF-β signaling in epithelial cells upon nasal infection with S. pneumoniae was also demonstrated in vivo. Inhibition of either p38 MAPK or TGF-β signaling was sufficient to inhibit the migration of S. pneumoniae or H. influenzae. Our data shows that diverse bacteria utilize common mechanisms, including MAPK and TGF-β signaling pathways to disrupt epithelial barriers and promote invasion.
Cardiac safety profile of prolonged (≥6 cycles) pegylated liposomal doxorubicin administration in patients with gynecologic malignancies

Abstract Objective . Pegylated liposomal doxorubicin (PLD) is currently utilized in the management of several solid tumors. While PLD has been shown to be less cardiotoxic than doxorubicin, the safety of prolonged administration (e.g., ≥6 cycles) of the agent remains undefined. Methods . A retrospective chart review was performed of the Cleveland Clinic experience from 1997 to 2003 with the prolonged (≥6 cycles) use of PLD in individuals with gynecologic malignancies. PLD was administered at doses ranging from 20 to 40 mg/m 2 (infused over 1–2 h) with treatment repeated every 4–6 weeks. While on therapy, patients underwent routine evaluation for toxicity, including the performance of multigated acquisition (MUGA) scans for determination of left ventricular ejection fraction (LVEF). Results . Twenty-two patients (18 ovarian cancer; 3 primary peritoneal cancer, 1 endometrial cancer) met the criteria for inclusion in this analysis. This population had received a median of 4 (range 1–8) chemotherapy regimens before initiation of PLD. No patient had previously received doxorubicin. The median number of PLD cycles and cumulative dose of LD delivered were 8 (range 6–26) and 483 mg/m 2 (256–1699 mg/m 2 ), respectively. One or more MUGA scans were obtained in 14 (64%) patients. No patient experienced clinical evidence (physical findings, symptoms) of heart failure. There were no dose reductions due to cardiac dysfunction, and no patient experienced a decline in LVEF to Conclusions . Prolonged therapy with PLD is possible in appropriately selected patients with advanced gynecologic malignancies. In this clinical setting, cardiac dysfunction does not appear to be a toxicity, which limits the duration of treatment. The development of evidence-based guidelines for monitoring cardiac function in this patient population would be quite useful.
The equilibrium structure of C70. An ab initio Hartree-Fock study

Abstract Ab initio self-consistent field (SCF) Hartree—Fock (HF) calculations employing basis sets of double-zeta plus polarization (dzP) quality are reported for C 70 . The D 5h rugby-ball shaped equilibrium geometry, obtained via analytic energy derivatives, is reminiscent of C 60 except for a ring of ten carbon atoms that give rise to a central band of five hexagons composed of aromatic CC bonds. The calculated ionization potential of C 70 (7.6 eV) is in excellent agreement with recent experimental measurements.
Approaches for Optimizing the First Electronic Hyperpolarizability of Conjugated Organic Molecules

A two-state, four-orbital, independent electron analysis of the first optical molecular hyperpolarizability, β, leads to the prediction that |β| maximizes at a combination of donor and acceptor strengths for a given conjugated bridge. Molecular design strategies that focus on the energetic manipulations of the bridge states are proposed for the optimization of β. The limitations of molecular classes based on common bridge structures are highlighted and more promising candidates are described. Experimental results supporting the validity of this approach are presented.
An analysis of refractory silicate nucleation via the theory of the physical spinodal

An analysis of experimental data has been conducted using the theory of the spinodal, as a test of its applicability to refractory vapors. A promising aspect of this approach is its prediction of a temperature and supersaturation at which there no longer exists a barrier to nucleation; such a phenomenon has been observed in both the SiO-H2 and MgSiO-H2 systems, where a small change in ambient temperature yielded 5-10 orders of magnitude increases in the nucleation rate within a few seconds.
Altered DNA binding and replication activities of JC virus T-antigen mutants.

Abstract Ten mutations were introduced into the JC virus (JCV) T antigen within a region corresponding to the SV40 T-antigen DNA binding domain (SV40 amino acids 131 to 220); nine of these increased homology between the two proteins in sequences critical for SV40 T antigen DNA binding. All mutant JCV T antigens bound to JCV and SV40 origins of DNA replication. Binding efficiency relative to that of wild-type JCV T antigen ranged from 83 to 301 % for the JCV binding sites and from 44 to 240% for the SV40 binding sites. Nine mutant proteins promoted viral DNA replication in primary human fetal glial (PHFG) and CV-1 cells. In PHFG cells, promotion of DNA replication ranged from 26 to 220% relative to that of wild-type T antigen; in CV-1 cells it ranged from 14 to 522%. Coding sequences for five mutant proteins were transferred into the hybrid virus M1(SV40) [M1(SV40) contains coding sequences from JCV and regulatory sequences from SV40]. Wild-type T antigen promoted replication weakly from the SV40 origin in these hybrid viruses in CV-1 cells (2% that from the JCV origin); replication driven by the mutant proteins ranged from 110 to 412% of that induced by the wild-type protein. Efficient specific DNA binding by a mutant T antigen was not a reliable indicator of that mutant protein's ability to promote DNA replication.
Estimating Indexes of Coincident and Leading IndicatorsAn Application to Jordan

The analysis of coincident and leading indicators can help policymakers gauge the short-term direction of economic activity. While such analysis is well established in advanced economies, it has received relatively little attention in many emerging market and developing economies, reflecting in part the lack of sufficient historical data to determine the reliability of these indicators. This paper presents an econometric approach to deriving composite indexes of coincident and leading indicators for a small open economy, Jordan. The results show that, even with limited monthly observations, it is possible to establish meaningful economic and statistically significant relations between indicators from different sectors of the economy and the present and future direction of economic activity.
A micromechanical model of surface steps

The surface of an epitaxial thin film typically consists of terraces separated by steps of atomic height and it evolves largely by the motion of steps. Steps are sources of stress that interact with other residual stress fields, and these interactions have a profound effect on surface evolution. A model of the elastic field arising from a two-dimensional step is presented as a departure from the commonly used half-plane point-multipole model. The field is calculated asymptotically for small step height up to second order in terms of ‘structural’ parameters that can be determined from empirical data or atomistic calculations. Effects of a lattice mismatch and surface stress are included. The model is shown to be in remarkable agreement with atomistic predictions. It is demonstrated that second-order terms are necessary for understanding non-trivial step–step interactions, and that these second-order fields cannot be described by point sources on a half-plane.
High frequency oscillations and infraslow activity in epilepsy

In pre-surgical evaluation of epilepsy, there has been an increased interest in the study of electroencephalogram (EEG) activity outside the 1-70 Hz band of conventional frequency activity (CFA). Research over the last couple of decades has shown that EEG activity in the 70-600 Hz range, termed high frequency oscillations (HFOs), can be recorded intracranially from all brain regions both interictally and at seizure onset. In patients with epilepsy, HFOs are now considered as pathologic regardless of their frequency band although it may be difficult to distinguish them from the physiologic HFOs, which occur in a similar frequency range. Interictal HFOs are likely to be confined mostly to the seizure onset zone, thus providing a new measure for localizing it. More importantly, several studies have linked HFOs to underlying epileptogenicity, suggesting that HFOs can serve as potential biomarkers for the illness. Along with HFOs, analysis of ictal baseline shifts (IBS; or direct current shifts) and infraslow activity (ISA) (ISA: <0.1 Hz) has also attracted attention. Studies have shown that: IBSs can be recorded using the routine AC amplifiers with long time constants; IBSs occur at the time of conventional EEG onset, but in a restricted spatial distribution compared with conventional frequencies; and inclusion of IBS contacts in the resection can be associated with favorable seizure outcome. Only a handful of studies have evaluated all the EEG frequencies together in the same patient group. The latter studies suggest that the seizure onset is best localized by the ictal HFOs, the IBSs tend to provide a broader localization and the conventional frequencies could be non-localizing. However, small number of patients included in these studies precludes definitive conclusions regarding post-operative seizure outcome based on selective or combined resection of HFO, IBS and CFA contacts. Large, preferably prospective, studies are needed to further evaluate the implications of different EEG frequencies in epilepsy.
Bird Community Response to Vegetation Cover and Composition in Riparian Habitats Dominated by Russian Olive (Elaeagnus angustifolia)

Abstract Riparian systems in the western United States provide important habitat for bird communities during all times of the year. In recent decades, invasive plants, such as Russian olive (Elaeagnus angustifolia), have achieved broad distribution and local dominance in many western riparian areas, raising concerns over the loss of ecological function within these systems. In 2005 and 2006 we conducted avian point counts and surveyed vegetation cover at 95 points along the Snake and Columbia Rivers in southeastern Washington to investigate the effects of total woody vegetation cover and the relative proportion of Russian olive cover on breeding and wintering riparian bird communities. Our results indicated that riparian habitats dominated by Russian olive can support diverse and abundant bird communities, though cavity nesting species were noticeably sparse. Bird density and species richness were best explained by a quadratic relationship to total woody vegetation cover in both seasons, as was breeding b...
The Influence of Atomizing Gas Molecular Weight on Low Mass Flowrate Effervescent Atomizer Performance

The relationship between atomizing gas molecular weight and spray mean drop size, Rosin-Rammler distribution parameter, and number averaged drop velocity is reported for a low mass flowrate effervescent atomizer-produced spray. Experimental data at lower gas-liquid ratios (GLR’s) demonstrate that an increase in the molecular weight of the atomizing gas increases mean drop size and decreases number averaged drop velocity. The increase in mean drop size is attributed to an increase in the thickness of the liquid annulus at the nozzle exit and a subsequent increase in the diameter of ligaments formed there. The decrease in number averaged velocity results from a decrease in jet momentum rate. A model developed to explain the atomization process indicates that the gas flow is choked at higher GLR’s.