cssi/SciSciGPT-SciSciNet huggingface dataset:
A Windowing Technique for Optimal Time-Frequency Concentration and ACI Rejection in OFDM-Based Systems

In this paper, we introduce a windowing technique, which provides optimal time-frequency containment and maximal adjacent channel interference (ACI) rejection for orthogonal frequency-division multiplexing (OFDM)-based systems. Instead of using a single pulse shape function for all subcarriers, multiple functions are considered in order to maximize the time-frequency containment of the OFDM waveform. The main strategy is to concentrate the spectrum of windowing functions into a given bandwidth while achieving maximum suppression in the out-of-band region. This is achieved by employing prolate-based windowing functions which give optimal spectral concentration for time-limited pulse shapes. The windowing functions are designed per-subcarrier basis in order to exploit available concentration band for each subcarrier. In addition, the proposed concept is considered for the receive filtering in the presence of ACI. It is shown that the optimal spectral concentration property also maximizes ACI rejection for OFDM receivers.
Sorting out relationships among the grouse and ptarmigan using intron, mitochondrial, and ultra-conserved element sequences

The Holarctic phasianid clade of the grouse and ptarmigan has received substantial attention in areas such as evolution of mating systems, display behavior, and population ecology related to their conservation and management as wild game species. There are multiple molecular phylogenetic studies that focus on grouse and ptarmigan. In spite of this, there is little consensus regarding historical relationships, particularly among genera, which has led to unstable and partial taxonomic revisions. We estimated the phylogeny of all currently recognized species using a combination of novel data from seven nuclear loci (largely intron sequences) and published data from one additional autosomal locus, two W-linked loci, and four mitochondrial regions. To explore relationships among genera and assess paraphyly of one genus more rigorously, we then added over 3000 ultra-conserved element (UCE) loci (over 1.7million bp) gathered using Illumina sequencing. The UCE topology agreed with that of the combined nuclear intron and previously published sequence data with 100% bootstrap support for all relationships. These data strongly support previous studies separating Bonasa from Tetrastes and Dendragapus from Falcipennis. However, the placement of Lagopus differed from previous studies, and we found no support for Falcipennis monophyly. Biogeographic analysis suggests that the ancestors of grouse and ptarmigan were distributed in the New World and subsequently underwent at least four dispersal events between the Old and New Worlds. Divergence time estimates from maternally-inherited and autosomal markers show stark differences across this clade, with divergence time estimates from maternally-inherited markers being nearly half that of the autosomal markers at some nodes, and nearly twice that at other nodes.
A prospective study of the predictive value of polymerase chain reaction assay for cytomegalovirus in asymptomatic kidney transplant recipients

Cytomegalovirus (CMV) infection carries the potential for high morbidity in transplant recipients. The institution of pre-emptive therapy prior to the onset of clinical disease on the basis of CMV-polymerase chain reaction (PCR) is very attractive. We prospectively studied 52 asymptomatic kidney transplant recipients to test the hypothesis that serial CMV-PCR assays during the first 3 months post-transplant would identify patients at risk for CMV disease. Twenty-three patients (44.2%) had positive CMV-PCR tests at least once; 2 (8.6%) developed CMV. None of the 29 patients continuously negative for CMV-PCR developed CMV disease. CMV-PCR status did not influence patient and graft survival or the incidence of acute rejection. We conclude that while a substantial number of kidney transplant recipients become positive for CMV-PCR in the early post-transplant period, only a minority will develop CMV disease. Negative CMV-PCR assay is an accurate negative predictor for CMV disease but the value of CMV-PCR as a guide for pre-emptive anti-CMV therapy in kidney transplant recipients appears limited.
Bifunctional polyamines for the aqueous dispersion of carbon nanotubes and the formation of carbon nanotube-impregnated hydrogel composites

The extraordinary electronic, thermal, and mechanical properties of carbon nanotubes (CNTs) make them attractive materials for incorporation into polymer films. However, retaining these outstanding properties of CNTs during processing can be difficult due to the attractive forces that cause the nanotubes to bundle together. In this study, six different hydrophobically modified linear poly(ethylenimine) (LPEI) polymers are evaluated and effectively used as aqueous nanotube dispersants. This study also shows that the polymers are bifunctional in nature as aqueous polymer/nanotube mixtures can be cross-linked into CNT-impregnated hydrogels.
Angular Rate Esimtation Using an Array of Fixed and Vibrating Triaxial Acceleration Measurements

† Assistant Professor, Department of Mechanical Engineering, Member AIAA ‡ Graduate Research Assistant, Department of Mechanical Engineering Copyright © 2003 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. ABSTRACT The work reported here describes a method for estimating angular velocity and angular acceleration of a body using clusters of seven triaxial linear acceleration measurements. Four of the triaxial sensors are fixed to the body while three of the sensors vibrate at a constant frequency with respect to the body. Unlike other existing solutions to this problem, the method described here does not require integration and also properly resolves the algebraic sign of the angular rates. After describing the basic method, the paper conducts an error analysis to identify critical design parameters of this sensor concept. The basic algorithm is shown to work well even in the presence of sensor noise, bias and cross axis sensitivity. Practical issues such as the required number of sensors, sensor arrangement, data fusion, and quantization errors are addressed.
A Contemporary Examination Of The Miles & Snow Strategic Typology Through The Lens Of Ambidexterity

Utilizing the lens of ambidexterity, the authors studied 503 diverse firms to determine how they address their entrepreneurial, engineering, and administrative problem domains and their association...
Temperature-dependent two-state dynamics of individual cooperatively rearranging regions on a glass surface.

Cooperatively rearranging regions (CRRs) play a central role in the temperature dependence of glass dynamics. We record real-time atomic resolution movies of individual CRRs, while ramping their temperature. Between 295 and 326 K, well below the bulk glass transition temperature ${T}_{g}$, the rate coefficient for two-state hopping of CRRs increases over tenfold, yielding an Arrhenius activation barrier of $\ensuremath{\approx}10{k}_{B}{T}_{g}$. By time resolving the dynamics of many individual CRRs, we show that highly stretched dynamics of the CRR ensemble results mainly from spatial heterogeneity, less from temporal heterogeneity of individual CRRs.
Improved Techniques Designed for Screening Candidate Termiticides on Soil in the Laboratory

Improved screening techniques provide a method for eliminating chemicals lacking the necessary toxicity or repellency for control of subterranean termites when the chemicals have been applied to the soil. Many chemicals have been screened and several have been selected for nationwide field testing as termiticides.
Spices and Flavoring Crops: Leaf and Floral Structures

The aromatic leaves and floral structures of more than 30 plants are commonly used as spices and flavorings. The leaves and floral structures have delicate flavors, and these spices require proper care, particularly during the drying process. Leaf spices are also used fresh. The diagnostic morphological and anatomical characters of the most commonly used spices are dealt with in detail, along with their common names, botanical names, family, and parts used. Handling, drying, and storage details are given wherever available. Additionally, data about antioxidant content and antifungal or bacterial properties have been given where applicable.
Ca2+/Calmodulin-dependent Protein Kinases

In this article the calcium/calmodulin-dependent protein kinases are reviewed. The primary focus is on the structure and function of this diverse family of enzymes, and the elegant regulation of their activity. Structures are compared in order to highlight the conserved architecture of their catalytic domains with respect to each other as well as protein kinase A, a prototype for kinase structure. In addition to reviewing structure and function in these enzymes, the variety of biological processes for which they play a mediating role are also examined. Finally, how the enzymes become activated in the intracellular setting is considered by exploring the reciprocal interactions that exist between calcium binding to calmodulin when interacting with the CaM-kinases.
A two-fingered underactuated anthropomorphic manipulator based on human precision manipulation motions

While designing robot hands based on grasping data is more common, fewer previous works have used details of human manipulation kinematics to improve robot hand design. The current work involves an underactuated, tendon driven, anthropomorphic manipulator with two flexor tendons and an abduction-adduction tendon, and describes its design based on experimental human precision manipulation data. Link lengths, joint axis alignment, and moment arms were derived from human subject data and values in the literature. The spring ratios, determining the torque relationships between joints, were then selected to maximize the achievable manipulation workspace from the human trial without requiring large forces, which are likely to lead to instability and object ejection. This is done by minimizing the stored spring energy in the robotic fingers across the range of precision manipulation workspace positions achieved by a representative human subject. After fabricating the hand, the energy characteristics of the resulting prototype are analyzed, and the robotic workspace is compared against the original human one. Despite only having three actuators, the hand is able to manipulate the test object within a 2.7 cm3 workspace volume, compared to an average human workspace of 5.4 cm3 for the same object. Future work could include adding antagonist actuators to achieve a larger motion range along the palmar-dorsal axis, which is currently the most limited axis of motion in comparison to the original human workspace.
Thermodynamics of the Flexible Metal-Organic Framework Material MIL-53(Cr) From First Principles

We use first-principles density functional theory total energy and linear response phonon calculations to compute the Helmholtz and Gibbs free energy as a function of temperature, pressure, and cell volume in the flexible metal-organic framework material MIL-53(Cr) within the quasiharmonic approximation. GGA and metaGGA calculations were performed, each including empirical van der Waals (vdW) forces under the D2, D3, or D3(BJ) parameterizations. At all temperatures up to 500 K and pressures from -30 MPa to 30 MPa, two minima in the free energy versus volume are found, corresponding to the narrow pore (np) and large pore (lp) structures. Critical positive and negative pressures are identified, beyond which there is only one free energy minimum. While all results overestimated the stability of the np phase relative to the lp phase, the best overall agreement with experiment is found for the metaGGA PBEsol+RTPSS+U+J approach with D3 or D3(BJ) vdW forces. For these parameterizations, the calculated free energy barrier for the np-lp transition is only 3 to 6 kJ per mole of Cr4(OH)4(C8H4O4)4.
Combined vascular and neurologic injury after cephalic vein cutdown approach for ICD implantation

In this article we discuss two cases that highlight possible complications of cardiac device implantation. In particular, our first case involves a patient who, during implantable cardioverter defibrillator (ICD) implantation, sustained injuries to her subclavian artery and vein and subsequently developed a self-resolving neuropraxia of the brachial plexus. In our second case, the patient, also during ICD implantation, had his left cephalic vein nicked during cutdown. Post-op he then developed a hematoma-induced left brachial plexus injury that also eventually self-resolved. A literature search has not shown other incidences of iatrogenic brachial plexus injuries from ICD implantation as described.
From Linkage to Economic Warfare: Energy, Soviet–American Relations, and the End of the Cold War

The policy of detente during the late 1960s and early 1970s opened up new prospects for Western–USSR cooperation, namely in the area of energy. US companies were at the forefront in exploring large investment options in the case of West Siberian gas. These projects failed, however, due to strong US domestic political opposition and a general worsening of US–USSR relations in the second half of the 1970s. Instead, military buildup and economic containment, including sanctions on pipeline technology, were to become the driving policies during the Reagan era, aiming at a weakening of the Soviet Union’s potential. In vain did Washington seek to obstruct the Europeans from building up their energy partnership with Moscow. The Soviet economy had already experienced first economic turbulences in the early 1980s, but when the price of oil fell in the mid-1980s, the country’s foreign currency reserves dwindled and the crisis worsened. When the Soviet Union eventually broke up in 1991, the so-called “Reagan victory school” saw this as, in retrospect, a vindication of Washington’s policy. In contrast, this chapter argues that US policies were not the main cause of the collapse in the oil price. In a longer perspective, by choosing confrontation over cooperation, the US not only exacerbated Cold War tensions and damaged relations with its allies, but also missed an opportunity to set in motion processes that might have ended the Cold War and facilitated reform in the Soviet Union without creating conditions that led to instability and future animosity.
Certification of nutrients in Standard reference material 1846: Infant Formula

In 1996, the National Institute of Standards and Technology (NIST) released Standard Reference Material 1846 (Infant Formula), which can be used as a control material for assigning values to in-house control materials and for validating analytical methods for measurement of proximates, vitamins, and minerals in infant formula and similar matrixes. The SRM was manufactured by preparing a spray-dried formula base containing fat, protein, carbohydrates, and minerals and then combining that formula base with a dry-blend vitamin premix that supplied the vitamins. The Certificate of Analysis for SRM 1846 provides assigned values for concentrations of proximates (fat, protein, etc.), vitamins, and minerals for which product labeling is required by the Infant Formula Act of 1980 and by the Nutrition Labeling and Education Act of 1990. These assigned values were based on agreement of measurements by NIST and/or collaborating laboratories. Certified values are provided for vitamins A (trans), E, C, B2, and B6 and niacin. Noncertified values are provided for solids, ash, fat, nitrogen, protein, carbohydrate, calories, vitamin D, delta-tocopherol, gamma-tocopherol, vitamin B1, vitamin B12, folic acid, pantothenic acid, biotin, choline, inositol, calcium, phosphorus, magnesium, iron, zinc, copper, sodium, potassium, and chloride. Information values are provided for iodine, manganese, selenium, and vitamin K.
Stochastic Control and Identification Enhancement for the Flutter Suppression Problem

Abstract The topic of this paper is the application of some recent results in stochastic control to an aerospace problem where there are large uncertainties in the dynamics of the plant to be controlled. An approximation to the stochastic Dynamic Programming is considered that results in an adaptive control of the “closed-loop” type: it utilizes feedback (latest state and parameter estimates and their uncertainties) as well as their anticipated future uncertainties - it anticipates (subject to causality) subsequent feedback. This algorithm has the feature that allows the control to enhance the parameter identification in real time. This is done using the control'invarianza dual effect: the control can affect the state as well as the (augmented) state uncertainty and thus can reduce the uncertainty about some parameters. A flight control application in which stochastic adaptive control appears to offer significant payoff is the active control of aircraft wing-store flutter. Improved flutter suppression can be accomplished with an adaptive controller that has the capability to learn and identify the flutter modes during the flight.
Solidarity as environmental justice in brownfields remediation

What do individuals owe to affected communities in the name of environmental justice? Principal accounts of environmental justice have made inroads in developing a pluralistic and activist-led appr...
Tailored survivorship care plans for head and neck cancer patients.

51Background: Survivorship care plans SCPs typically include generic advice for cancer surveillance, management of late effects (LEs), wellness recommendations (WRs), and cancer screening. We devel...
'Keeper of the fire': human resource management's role in the organisational development of an employee sustainability mindset

Sustainability is "meeting the needs and demands of today without compromising the ability of future generations to meet their requirements" [Burton, (1987), p.8] Sustainable development requires that organisations' social, environmental, well-being, and economic factors are managed in balance and from short and long-term as well as external and internal perspectives organisations have been advised to yoke sustainability practice to virtually every facet of an organisation's strategic management process, including human resource management as a functional level organisational strategic unit In recent years, human resource management (HRM) has been highlighted as a key agent with which to advance the firm because it is a central internal consultant for all matters of human capital management Thusly positioned, HRM can play a critical role in engendering employee sustainability practices. The purpose of this paper is to flesh out a key, core role for HRM as 'keeper of the fire' of an employee sustainability mindset Essentials of mindset are first developed, then the sustainability mindset and its integration into HRM and employee practices is explored Finally, critical concerns and future directions for sustainable HRM practice are examined.
Neurogenic hypertension: pathophysiology, diagnosis and management

Discussions about the cause and treatment of essential hypertension usually focus on mechanisms such as sodium/volume and the renin–angiotensin system. Less often discussed is hypertension driven by the sympathetic nervous system, i.e., neurogenic hypertension. In this review I discuss the pathophysiology of neurogenic hypertension, the controversy of renal versus central origin, the clinical clues that suggest neurogenic hypertension, and the interventions best suited in its treatment. Neurogenic hypertension is most likely to occur in patients with labile or paroxysmal hypertension, but evidence of increased sympathetic tone also suggests a neurogenic component in hypertension in patients with severe or resistant hypertension, chronic renal disease, comorbidities associated with increased sympathetic tone, and ingestion of drugs that stimulate sympathetic tone. The importance of combined alpha- and beta-blockade in pharmacologic treatment and the status of renal denervation are discussed. Although there is much that is unclear in its pathophysiology, recognition of neurogenic hypertension is of considerable clinical importance in individualizing drug therapy and achieving blood pressure control.
Normal Pregnancy, Pregnancy Complications, and Obstetric Management

Profound changes in maternal physiology occur during pregnancy to accommodate the growing fetus. Understanding these changes is fundamental to proper management of the obstetric patient and identification of pathologic changes. This chapter provides an overview of the obstetric patient and serves to familiarize the rheumatologist with pregnancy. First, we address normal fetal development followed by the various maternal physiologic changes that occur in major organ systems. Next we address antenatal care and fetal surveillance. Finally, we discuss common complications of pregnancy, some of which may mimic rheumatologic conditions or occur in greater frequency in the woman with underlying rheumatic disease. This chapter lays the foundation required to understand the nuances of pregnancy management in each specific rheumatologic disease.
Triune Brain Concept: A Comparative Evolutionary Perspective

Paul MacLean’s triune brain model essentially states that the brains of extant mammals, including humans, evolved by the sequential gain of some limbic and all neocortical components, added onto an ancestral ‘reptilian’ core, the basal ganglia. While this model has been enthusiastically adopted by some neuroscientists, particularly those with interests in psychiatry, it has been dismissed as evolutionarily incorrect and of no heuristic value by those in comparative, evolutionary neurobiology. An alternative, more objective model of amniote brain evolution is offered, based on the latter perspective, that allows for a broader consideration of how higher cognitive processes are generated.
Classification of protein kinases into messenger-dependent and independent kinases. The regulation of independent kinases.

This paper is divided into three sections. The first section gives an overview of the protein phosphorylation-dephosphorylation process. The second section presents a classification scheme for the protein kinases, and the third section constitutes a brief review of casein kinase II and describes recent work that is being carried out in our laboratory on this messenger-independent protein kinase.
Revisiting the Newsvendor and Traveling Salesman in a Healthcare Disaster or Pandemic Response

There are significant challenges to provide timely relief in healthcare disaster and pandemic response situations. The impact of these types of events risk large number of people to potentially fatal outcomes. A key element of providing timely relief is the distribution of critical medicines and supplies. Based on current literature, there appears to be a gap between simplistic solutions and complex optimization models. The goal of this paper is to provide a useful model that can be applied in time critical healthcare and pandemic situations.
Free-Breathing Fast Low-Angle Shot Quiescent-Interval Slice-Selective Magnetic Resonance Angiography for Improved Detection of Vascular Stenoses in the Pelvis and Abdomen: Technical Development.

OBJECTIVES Balanced steady-state free precession-based quiescent-interval slice-selective (bSSFP QISS) magnetic resonance angiography (MRA) is accurate for the noncontrast evaluation of peripheral arterial disease (PAD); however, drawbacks include the need for breath-holding when imaging the abdomen and pelvis, and sensitivity to off-resonance artifacts. The purpose of this study was to evaluate the image quality and diagnostic accuracy in the pelvis and abdomen of free-breathing fast low-angle shot-based QISS (FLASH QISS) techniques in comparison to bSSFP QISS in patients with PAD, using computed tomographic angiography as the reference. MATERIALS AND METHODS Twenty-seven patients (69 ± 10 years, 17 men) with PAD were enrolled in this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant prospective study between April and December 2018. Patients underwent noncontrast MRA using standard bSSFP QISS and prototype free-breathing radial-FLASH and Cartesian-FLASH QISS at 3 T. A subset of patients (n = 22) also underwent computed tomographic angiography as the reference standard. Nine arterial segments per patient were evaluated spanning the abdomen, pelvis, and upper thigh regions. Objective (signal intensity ratio and relative standard deviation) and subjective image quality (4-point scale) and stenosis (>50%) were evaluated by 2 readers and compared using one-way analysis of variance, Wilcoxon, and McNemar tests, respectively. RESULTS A total of 179 vascular segments were available for analysis by all QISS techniques. No significant difference was observed among bSSFP, radial-FLASH, and Cartesian-FLASH QISS techniques in signal intensity ratio (P = 0.428) and relative standard deviation (P = 0.220). Radial-FLASH QISS demonstrated the best image quality (P < 0.0001) and the highest interreader agreement (κ = 0.721). The sensitivity values of bSSFP, radial-FLASH, and Cartesian-FLASH QISS for the detection of greater than 50% stenosis were 76.0%, 84.0%, and 80.0%, respectively, whereas specificity values were 97.6%, 94.0%, and 92.8%, respectively. Moreover, FLASH QISS consistently reduced off-resonance artifacts compared with bSSFP QISS. CONCLUSIONS Free-breathing FLASH QISS MRA techniques provide improved image quality and sensitivity, high specificity, and reduced off-resonance artifacts for vascular stenosis detection in the abdomen and pelvis.
An Exploration of Civic Identity in First-Generation College Students: From Charity to Solidarity

The intertwining effects of the college environment and first-generation status on student civic engagement have not been examined in detail, yet this information is essential to support the develo...
Cost of Austerity: Effect of Fiscal Consolidation in Europe Post 2010

This paper investigates the effect of fiscal consolidation on GDP per capita following the 2008 Financial Crisis and European Debt Crisis. I use the synthetic control method to assess the GDP performance of three European countries that pursued large quantities of fiscal consolidation: Greece, Spain and Italy. I estimate that without fiscal consolidation GDP per capita would have been 30, 11, and 17 percent higher in each country respectively.
A Review of Generalizability and Transportability

When assessing causal effects, determining the target population to which the results are intended to generalize is a critical decision. Randomized and observational studies each have strengths and limitations for estimating causal effects in a target population. Estimates from randomized data may have internal validity but are often not representative of the target population. Observational data may better reflect the target population, and hence be more likely to have external validity, but are subject to potential bias due to unmeasured confounding. While much of the causal inference literature has focused on addressing internal validity bias, both internal and external validity are necessary for unbiased estimates in a target population. This paper presents a framework for addressing external validity bias, including a synthesis of approaches for generalizability and transportability, the assumptions they require, as well as tests for the heterogeneity of treatment effects and differences between study and target populations.
Rare left colic artery variation of the gut arterial system

Most variations of the abdominal blood supply are related to branching of the celiac trunk and superior mesenteric artery. This case details a remarkable variation in the branching pattern of the left colic artery (LCA) observed during routine cadaveric dissection of an 84-year-old male donor. An anomalous common trunk, originating from the common hepatic artery, gave rise to three branches: 1) an accessory posterior pancreaticoduodenal artery to the head of the pancreas and adjacent duodenum, 2) the dorsal pancreatic artery anastomosing with branches of the splenic artery, and 3) the LCA. The LCA descended between the splenic vein and superior mesenteric artery to supply the left colic flexure and form a collateral route with the middle colic artery by contributing to the marginal artery of Drummond. Knowledge of this variation is clinically relevant for surgical and radiological procedures in the abdomen.
Systems Optimization on Retinal Research

The analisys of the properties of specialized cells in the retina using concepts from Systems Theory allow us to exclude several retinal mechanisms in the generation of responses to spatial and temporal stimuli, suggesting other mechanisms as more probable. We need more experimentation to clarify the underlying mechanisms.
The Emotions Thermometer: An Intervention for the Scaling and Psychoeducation of Intense Emotions

This article introduces a technique for the scaling of emotions and the psychoeducation of brain activity and physiological responses associated with intense emotions. The technique is simple to use and provides an illustration of a thermometer with emotional intensity scaled on one side and available intelligence inversely scaled on the other side. The emotions thermometer allows clients to describe and process their emotional experience in a concrete and specific manner. The technique can be integrated into a wide variety of therapeutic methods. A case example is provided.
Decision tree evolution using limited number of labeled data items from drifting data streams

Most previously proposed mining methods on data streams make an unrealistic assumption that "labelled" data stream is readily available and can be mined at anytime. However, in most real-world problems, labelled data streams are rarely immediately available. Due to this reason, models are reconstructed only when labelled data become available periodically. This passive stream mining model has several drawbacks. We propose a concept of demand-driven active data mining. In active mining, the loss of the model is either continuously guessed without using any true class labels or estimated, whenever necessary, from a small number of instances whose actual class labels are verified by paying an affordable cost. When the estimated loss is more than a tolerable threshold, the model evolves by using a small number of instances with verified true class labels. Previous work on active mining concentrates on error guess and estimation. In this paper, we discuss several approaches on decision tree evolution.
Applying action attribute class validation to improve human activity recognition

When learning a new classifier, poor quality training data can significantly degrade performance. Applying selection conditions to the training data can prevent mislabeled, noisy, or damaged data from skewing the classifier. We extend a set of action attributes and apply training case attribute selection conditions to a challenging action recognition dataset.
Diffusion in three-dimensionally ordered scaffolds with inverted colloidal crystal geometry

Abstract Inverted colloidal crystal geometry has been recently utilized in the design of highly organized 3D cell scaffolds. The regularity of the resulting scaffolds enables computational modeling of scaffold properties. In this work we probe the resistance offered by these scaffolds to nutrient transport, by using Brownian dynamics and Monte Carlo simulations to model the effective nutrient diffusivity. Brownian dynamics simulations indicate that the effective diffusivity for small nutrients in the scaffold, D eff = 0.3 D 0 , where D 0 is the free solution diffusivity. Further, results of Monte Carlo simulations for dilute solutions of larger particles show that the D eff decreases linearly with the size of the particles.
Efflux of hydraulically lifted water from mycorrhizal fungal hyphae during imposed drought

Apart from improving plant and soil water status during drought, it has been suggested that hydraulic lift (HL) could enhance plant nutrient capture through the flow of mineral nutrients directly from the soil to plant roots, or by maintaining the functioning of mycorrhizal fungi. We evaluated the extent to which the diel cycle of water availability created by HL covaries with the efflux of HL water from the tips of extramatrical (external) mycorrhizal hyphae, and the possible effects on biogeochemical processes. Phenotypic mycorrhizal fungal variables, such as total and live hyphal lengths, were positively correlated with HL efflux from hyphae, soil water potential (dawn), and plant response variables (foliar 15 N). The efflux of HL water from hyphae was also correlated with bacterial abundance and soil enzyme activity (P), and the moistening of soil organic matter. Such findings indicate that the efflux of HL water from the external mycorrhizal mycelia may be a complementary explanation for plant nutrient acquisition and survival during drought.
Endometriosis and Tissue Factor

Tissue factor (TF), is a cellular receptor that binds the ligand factor VII/VIIa to initiate the blood coagulation cascade. In addition to its role as the initiator of the hemostatic cascade, TF is known to be involved in angiogenesis via an interaction with factor VIIa and protease-activated receptor-2 (PAR-2). In this article we review previous studies from our laboratory demonstrating that the pattern and level of TF expression is altered in multiple cell types derived from eutopic and ectopic endometrium from women with endometriosis compared with normal endometrium. We posit that the inflammatory environment that occurs in ectopic and eutopic endometrium from patients with disease results in high TF expression that in turn, signals via PAR-2 to further produce inflammatory cytokine or chemokine production and macrophage recruitment. Thus, our studies suggest that TF might be an ideal target for therapeutic intervention in endometriosis.
Solution Structure of Proinsulin: CONNECTING DOMAIN FLEXIBILITY AND PROHORMONE PROCESSING*

The folding of proinsulin, the single-chain precursor of insulin, ensures native disulfide pairing in pancreatic β-cells. Mutations that impair folding cause neonatal diabetes mellitus. Although the classical structure of insulin is well established, proinsulin is refractory to crystallization. Here, we employ heteronuclear NMR spectroscopy to characterize a monomeric analogue. Proinsulin contains a native-like insulin moiety (A- and B-domains); the tethered connecting (C) domain (as probed by {1H}-15N nuclear Overhauser enhancements) is progressively less ordered. Although the BC junction is flexible, residues near the CA junction exhibit α-helical-like features. Relative to canonical α-helices, however, segmental 13Cα/β chemical shifts are attenuated, suggesting that this junction and contiguous A-chain residues are molten. We propose that flexibility at each C-domain junction facilitates prohormone processing. Studies of protease SPC3 (PC1/3) suggest that C-domain sequences contribute to cleavage site selection. The structure of proinsulin provides a foundation for studies of insulin biosynthesis and its impairment in monogenic forms of diabetes mellitus.
Nitrous oxide analgesia in humans: Acute and chronic tolerance

Abstract Electrical tooth stimulation was used to investigate whether humans develop tolerance to nitrous oxide (N2O) analgesia within a single administration as well as over repeated administrations. In a double-blind cross-over experiment, 77 subjects received a 40-min administration of 38% N2O at one session and placebo gas at the other. The sessions were separated by 1 week and the order of gas administration was counterbalanced. Acute analgesic tolerance developed for pain threshold but not for detection threshold. There was no evidence of a hyperalgesic rebound effect following cessation of the N2O administration. In a second double-blind experiment, 64 subjects received both 30-min of placebo gas and 30-min of 35% N2O, separated by a 35-min gas wash-out period, during each of five sessions. Sensory thresholds were assessed prior to drug or placebo administration (baseline) and between 7–12 and 25–30 min of gas administration. A control group of 16 subjects received only placebo gas at these five sessions. During a sixth session, the experimental procedures were similar to the previous sessions except that the control group received N2O for the first time and the experimental group was sub-divided to test for conditioned drug effects. For both detection and pain threshold measures, acute tolerance developed during the initial N2O exposure and chronic tolerance developed over repeated administrations. Although chronic tolerance developed, a test for Pavlovian drug conditioning found no evidence of conditioned effects on sensory thresholds. In conclusion, acute and chronic tolerance develop to N2O's analgesic effects in humans.
Regular Article: An Accurate Cartesian Grid Method for Viscous Incompressible Flows with Complex Immersed Boundaries

A Cartesian grid method has been developed for simulating two-dimensional unsteady, viscous, incompressible flows with complex immersed boundaries. A finite-volume method based on a second-order accurate central-difference scheme is used in conjunction with a two-step fractional-step procedure. The key aspects that need to be considered in developing such a solver are imposition of boundary conditions on the immersed boundaries and accurate discretization of the governing equation in cells that are cut by these boundaries. A new interpolation procedure is presented which allows systematic development of a spatial discretization scheme that preserves the second-order spatial accuracy of the underlying solver. The presence of immersed boundaries alters the conditioning of the linear operators and this can slow down the iterative solution of these equations. The convergence is accelerated by using a preconditioned conjugate gradient method where the preconditioner takes advantage of the structured nature of the underlying mesh. The accuracy and fidelity of the solver is validated by simulating a number of canonical flows and the ability of the solver to simulate flows with very complicated immersed boundaries is demonstrated.
Community consultation: not the problem--an important part of the solution.

In “Accidental Communities: Race, Emergency Medicine, and the Problem of PolyHeme®,” Holloway illustrates some of the complexities related to involving communities in reviewing and conducting clini...
Hybrid phosphazene-organosilicon polymers: I. Background, rationale, and small-molecule model compound chemistry

Most of the polymers that have been synthesized and studied over the past 50 years are organic macromolecules. However, many advantages exist for the development of polymers with inorganic backbones. The first major class of inorganic backbone polymers to be developed widely were the poly(organosiloxanes) (silicones), and these now are the subject of broad industrial and fundamental interest. Polyphosphazenes are a relatively new class of inorganic backbone polymers which rival many organic systems in their molecular structural diversity and property variations. They constitute only the second group of inorganic-organic polymers to be developed extensively. An emerging field of research involves an attempt to create a new area of polymer science at the interface between these two subjects, by the synthesis of hybrid organophosphazene organosilicon systems. This review is a summary of recent progress in this new field.
IgD-receptor up-regulation on human peripheral blood T cells in response to IgD in vitro or antigen in vivo correlates with the antibody response to influenza vaccination

Aged individuals (more than 65 years) were classified as antibody (Ab) responders on the basis that they showed increases to more than or = 1:40 in serum Ab titers to all influenza virus strains present in the trivalent influenza vaccine within 4 weeks after immunization. The peripheral blood mononuclear cells (PBMC) from pre-immunization samples of blood taken from seven Ab-responders and seven Ab-nonresponders were examined for their ability to exhibit up-regulation of IgD-receptor (IgD-R) after exposure for 2 h to immobilized cross-linked IgD, as shown by rosetting with IgD-coated ox erythrocytes. The responsiveness to IgD was found to be predictive of the ability to produce Ab responses to viral protein Ag: the IgD-R up-regulation was greater than 5% in all Ab-responders and less than 4% in all the Ab-nonresponders. In addition, there was an excellent correlation between mean Ab titers (to the three viruses in sera collected 4 weeks after immunization) and the percentage of IgD-R+ cells obtained in response to IgD in PBMC from the same individual prior to immunization: p = 0.894. Injection of influenza vaccine itself also induced IgD-R on PBMC in vivo. The percentage of IgD-R+ cells peaked after 24 h, was still detectable above background by day 7 or 14, and returned to pre-injection levels by day 28 in young subjects and aged Ab-responders, but not in Ab-nonresponders. Similarly, purified peripheral blood T cells obtained from aged Ab-responders exhibited IgD-R upon immunization in vivo. These findings suggest that Ag injection causes rapid up-regulation of IgD-R by cross-linking IgD in humans as well as in mice as shown previously. In analogy with results in mice, the present data are consistent with a role for IgD-R+ T cells in the humoral response in man. Proliferative responses to influenza proteins in peripheral blood T cells from vaccinated individuals were found to peak on day 7 and were higher in Ab-responders than in Ab-nonresponders.
Geometric design of microfluidic chambers: platelet adhesion versus accumulation

Arterial, platelet-rich thrombosis depends on shear rates and integrin binding to either a collagen surface or to the growing thrombus, which are mechanistically different. In general, small microfluidic test sections may favor platelet-surface adhesion without testing for the primary mode of intra-arterial thrombosis, i.e. platelet-platelet bonding and accumulation. In the present report, the ratio of platelet-platelet to platelet-surface interactions, R, and the percentage of platelet-platelet interactions, P, are estimated using an analytical approach for circular and rectangular test sections. Results show that the test section geometry strongly affects both R and P, with test section height in low-aspect ratio channels or diameter greater than 90 μm dominated by platelet-platelet interactions (R > 10). Increasing rectangular test section aspect ratio decreases the required height. R increases linearly while P approaches 100 % asymptotically with increasing channel dimension. Analysis of platelet shape shows that the assumption of spherical platelets has a small effect on R compared to discoid platelets adhering flat against test section wall. However, an increase in average platelet volume resulted in a large decrease in R. Nonetheless, Monte Carlo simulations of a typical distribution of human platelet sizes show intrasubject variation in platelet size has only a 10 % net effect on R. Finally, experiments of thrombus formation show that platelet-surface lag times and platelet-platelet accumulation are similar for rectangular microfluidic test sections and round test sections when R > 10. The findings show that the size of a microfluidic test section should be carefully considered in studies of cell-cell accumulation versus cell-surface adhesion.
New Substrates for Polymer Cationization with Time-of-Flight Secondary Ion Mass Spectrometry

Cationization of large polymers and their fragments on novel self-assembled monolayer substrates has been studied with time-of-flight secondary ion mass spectrometry (ToF-SIMS). Low (1 kDa) and high (400 kDa) molecular weight poly(ethylene oxide) (PEO) were spin-coated on metal ion substituted, carboxylic terminated, self-assembled monolayers on gold. Both cationized fragments and additional whole molecular species were observed for the 1 kDa PEO, while for 400 kDa PEO, only chain fragments of up to 30 monomer units were detected. Fragmentation pattern dependence on polymer molecular weight and the nature of the substrate is discussed. The intensity of the cationized fragments was found to depend on the metal ion used. Complementary experiments carried out on methyl terminated self-assembled monolayers suggested that metal ions that are desorbed from the gold surface, and therefore not in close proximity to the polymer, do not cationize polymers and their fragments. The substrates used in this work are si...
Evidence for 12-lipoxygenase induction in the vessel wall following balloon injury.

Objective: Vascular smooth muscle cell (VSMC) migration and proliferation are key events in the development of atherosclerosis and restenosis following angioplasty. These events are mediated by several growth factors and cytokines whose cellular effects include activation of phospholipases and arachidonic acid metabolism via the lipoxygenase (LO) pathway. Since 12-LO products have potent growth and chemotactic effects, we have examined if 12-LO is upregulated in the neointima of injured rat carotid arteries and also if LO inhibition could attenuate neointimal thickening. Methods: The left common carotid arteries of male Sprague Dawley rats were injured using a 1.8F PTCA balloon catheter. Four–fourteen days after injury, injured and uninjured tissue samples were processed for histology, and immunohistochemistry or polymerase chain reaction (PCR) to examine 12-LO expression. Results: Twelve days after injury, immunohistochemical staining with a 12-LO antibody revealed intense staining in injured left carotid arteries, mainly in neointimal VSMCs and inflammatory cells, but not in the uninjured right arteries. There was also a marked upregulation of 12-LO mRNA (over five-fold by competitive PCR) in the injured arteries. Treatment of the arteries with a LO inhibitor, phenidone, soon after injury resulted in significant inhibition of neointimal thickening. In contrast, a cyclooxygenase inhibitor, ibuprofen, had no effect. Conclusions: These results indicate for the first time that balloon injury results in marked induction of 12-LO mRNA and protein expression in the vessel wall. Furthermore, LO pathway activation may mediate, at least in part, the development of the lesion or plaque instability, suggesting a novel target for therapeutic intervention to block these pathological events.
High-efficiency three-terminal laser array for optical interconnect

Strained InGaAs/GaAs quantum well three terminal lasers with monolithically integrated intracavity modulators were fabricated using low threshold current structures formed by the temperature engineered growth (TEG) technique. An on-off efficiency ratio of 556 with optical power contrast ratio of 7.5 was measured with a total DC power consumption of 25.3 mW. Preliminary digital modulation shows bit error rate (BER) lower than 10 -16 at 500 Mb/s. A theoretical analysis of the dynamic behavior of this device shows potential operation of 6.6 Gb/s with low inter-symbol interference.
Sand Suspension and Transport on Equilibrium Beach

A time-dependent cross-shore model for sand suspension and transport in the surf zone on a beach is compared with an irregular wave experiment that was conducted on an equilibrium terraced beach, consisting of fine sand in a wave flume. The measured free surface elevations and cross-shore velocities dominated by irregular wave motions are predicted within errors of the order of 20%. The measured sand concentrations dominated by intermittent high suspension events are predicted only within a factor of about two, because this ID numerical model does not account for sand suspension processes due to eddies and turbulence generated by irregular breaking waves. The computed net cross-shore sediment transport rate is relatively small and is not zero when the net rate must be zero for the equilibrium beach. Relatedly, the computed difference between the time-averaged sand suspension and settling rates is relatively small and is not zero. A better understanding of sand suspension processes will be required to predict the small net rates more accurately.