cssi/SciSciGPT-SciSciNet huggingface dataset:
Sleep disordered breathing in spinal cord injury: A systematic review

Context: Spinal cord injury commonly results in neuromuscular weakness that impacts respiratory function. This would be expected to be associated with an increased likelihood of sleep-disordered breathing.Objective: (1) Understand the incidence and prevalence of sleep disordered breathing in spinal cord injury. (2) Understand the relationship between injury and patient characteristics and the incidence of sleep disordered breathing in spinal cord injury. (3) Distinguish between obstructive sleep apnea and central sleep apnea incidence in spinal cord injury. (4) Clarify the relationship between sleep disordered breathing and stroke, myocardial infarction, metabolic dysfunction, injuries, autonomic dysreflexia and spasticity incidence in persons with spinal cord injury. (5) Understand treatment tolerance and outcome in persons with spinal cord injury and sleep disordered breathing.Methods: Extensive database search including PubMed, Cochrane Library, CINAHL and Web of Science.Results: Given the current lite...
Electronic, elastic, and fracture properties of trialuminide alloys: Al3Sc and Al3Ti

The electronic mechanism behind the brittle fracture of trialuminide alloys is investigated using the full-potential linearized augmented plane-wave (FLAPW) total-energy method within the local density functional approach. To this end, the bulk phase stability, the elastic constants, the anti-phase boundary (APB) energy, the superlattice intrinsic stacking fault (SISF) energy, and the cleavage energy on different crystallographic planes have been determined. A small energy difference (=0.10 eV/unit formula) is found between the DO22 and L12 structures of Al3Ti. In general, the trialuminide alloys have large elastic modulus, small Poisson's ratio, and small shear modulus to bulk modulus ratio. An extremely high APB energy (=670 mJ/m2) on the (111) plane is found for Al3Sc, indicating that the separation between ½(110) partials of a (110)(111) superdislocation is small. Since the total superdislocation has to be nucleated essentially at the same time, a high critical stress factor for dislocation emission at the crack tip is suggested. The high APB energy on the (111) plane is attributed to the directional bonding of Sc(d-electron)-Al(p-electron). The same type of directional bonds is also found for Al3Ti. In addition, moderately high values of SISF energy (=265 mJ/m2) on the (111) plane and APB energy (=450 mJ/m2) on the (100) plane are found for Al3Sc. The brittle fracture of trialuminide alloys is attributed to the higher stacking fault energies and a lower cleavage strength compared to those of a ductile alloy (e.g., Ni3Al). While the (110) surface has the highest surface energy, the cleavage strength (=19 GPa) of Al3Sc is found to be essentially independent of the crystallographic planes. The directional Sc—Al bond becomes even stronger on the (110) surface, which may explain the preferred (110) type cleavage observed by experiment.
YSZ-Based Electrochemical Gas Sensors for the Detection of Explosives

A zirconia-based mixed potential sensor utilizing dense lanthanum chromite and Pt electrodes and porous YSZ electrolyte was used in an alternating HC mode (unbiased) and total NOx mode (50 nA bias current applied) to detect the HC and NOx deflagration remnants of a nitroglycerin/nitrocellulose propellant (Bullseye{trade mark, serif}), ANFO (ammonium nitrate and fuel oil), blackpowder, and urea (a common, high nitrogen content fertilizer.) Unique HC and NOx sensor responses taken together with sufficient sensitivity to detect microgram quantities of Bullseye{trade mark, serif} - both directly and via capture of trace residue by swiping contaminated surfaces- suggest that detection and discrimination of HE using zirconia-based mixed potentials is possible.
Ring-substituted α-arylalanines for probing substituent effects on the isomerization reaction catalyzed by an aminomutase

β-Amino acids are emerging as an important class of compounds in medicinal chemistry. β-Aryl-β-alanines show antiepileptogenesis activity, while others have been used to synthesize antibiotic β-peptides. To assess the utility of a methylidene imidazolone-dependent Pantoea agglomerans phenylalanine aminomutase (PaPAM) for making non-natural β-amino acids, we surveyed the substrate specificity of PaPAM with several commercially available (S)-arylalanine substrates. Here, we report the Michaelis–Menten parameters and catalytic efficiency of PaPAM for each substrate. Compared to phenylalanine, substrates containing substituents that were either electron-withdrawing or -donating through resonance or inductive effects affected the kcat of PaPAM. Generally, the turnover and catalytic efficiency of PaPAM for the meta-isomers were better than for the corresponding para- and ortho-isomers, with some exceptions. PaPAM principally synthesizes the β-amino acids at >90% and the cinnamate byproducts at <10% for 11 of th...
Lateral branch formation and cellulase production in the water molds.

The formation of lateral branches, in response to induction by metabolites containing amino acids, in the genera Achlya, Saprolegnia and Dictyuchus is accompanied by the production and release of the enzyme cellulase. Treatments which prevent the production and release of cellulase also prevent the formation of lateral branches. Inhibitor studies with cycloheximide indicate that the branching/cellulase response requires protein synthesis.
Clinical Features of Prolonged Febrile Seizures

The results of a prospective, multicenter study of 119 children (age 1 month through 5 years) with prolonged febrile seizures (30 min or longer) are reported from Montefiore Medical Center, and Columbia University, New York; Children's Memorial Hospital, Chicago; and other members of the FEBSTAT study group.
Connecting Poverty, Culture, and Cognition: The Bridges Out of Poverty Process

ABSTRACTThis article highlights how one nonprofit organization deals with the controversial issue of culture and poverty through its interactions with low-income individuals. Through interviews and participant observation, we analyze its curriculum and process, which focuses on helping participants become more reflexive by analyzing their past life and potential futures through a social class analysis. At the same time, we discuss a key theoretical debate over culture and action/agency. Specifically, we examine the distinction between practical and discursive consciousness (or declarative and non-declarative culture), and issues of agency. We show how this theoretical process is accomplished in the organization by providing people with the opportunity to change their habits, skills, “cultured capacities” and “repertoires,” which can help them get out of poverty. We also show other factors, such as social support, are crucial and how the overall process works more for some than for others.
History and Current Substance Use

Publisher Summary This chapter provides an overview of empirically supported measures of alcohol and other drug consumption that can be applied in clinical and clinical research contexts. It is evident that a number of interview/self-report measures are available for use with adolescents or adults that vary sufficiently in content and resources needed for their application to meet virtually all clinical and clinical research needs. The field is rapidly advancing in the technology of biomarkers, each providing different types of information. For both self-report/interview and biomarker measures, there is no one gold standard of perfect accuracy, so the strategy most likely to yield the most accurate representation of an individual's substance use is one utilizing a convergent validity approach. Many excellent, empirically supported instruments have been developed to measure history of and current alcohol and other drug use. The characteristics of these instruments are varied enough to provide clinicians and researchers with reliable tools to meet any assessment need. This advanced level of development of self-report/interview methods of measuring alcohol and other drug consumption is a product of past and current emphasis on the use of empirically supported self-report or interview methods of data collection in both clinical and research contexts.
Option Pricing Via Genetic Programming

We propose a methodology of Genetic Programming to approximate the relationship between the option price, its contract terms and the properties of the underlying stock price. An important advantage of the Genetic Programming approach is that we can incorporate currently known formulas, such as the Black-Scholes model, in the search for the best approximation to the true pricing formula. Using Monte Carlo simulations, we show that the Genetic Programming model approximates the true solution better than the Black-Scholes model when stock prices follow a jump-diffusion process. We also show that the Genetic Programming model outperforms various other models when pricing options in the real world. Other advantages of the Genetic Programming approach include its low demand for data, and its computational speed.
Estimation and detection in the presence of ringing noise

To minimize size and cost, most air coupled ultrasound range systems are designed as mono-static systems, where the same transducer is used for both transmission and reception. Mono-static systems suffer from a type of self interference which is referred to as ringing noise or ring-down. Ringing noise may occlude echoes from nearby targets, compromising the detection performance of the system at short ranges. This paper describes a simple method for detecting target returns embedded in ringing noise and compares the performance of the proposed method to a more popular CFAR technique.
The Future of Youth Development: Multiple Wisdoms, Alternate Pathways and Aligned Accountability

Based on trends and events observed or experienced by the author over the last 30 years in research, evaluation and practice, this article examines three challenges facing and shaping the future of the youth programs as contexts for development. The first challenge surrounds how the field comes to understand, value and integrate different forms of knowing -- particularly quantitative data. The second challenge represents how the field shifts from proving it makes a difference to improving the ways it makes a difference by expanding the pathways to impact. The third challenge regards how the field responds to and shapes accountability pressures in ways that better align accountability rather than succumb to it. Implications of each challenge for effectively bridging research and practice are noted.
Statistical Approaches to Candidate Biomarker Panel Selection

The statistical analysis of robust biomarker candidates is a complex process, and is involved in several key steps in the overall biomarker development pipeline (see Fig. 22.1, Chap. 19). Initially, data visualization (Sect. 22.1, below) is important to determine outliers and to get a feel for the nature of the data and whether there appear to be any differences among the groups being examined. From there, the data must be pre-processed (Sect. 22.2) so that outliers are handled, missing values are dealt with, and normality is assessed. Once the processed data has been cleaned and is ready for downstream analysis, hypothesis tests (Sect. 22.3) are performed, and proteins that are differentially expressed are identified. Since the number of differentially expressed proteins is usually larger than warrants further investigation (50+ proteins versus just a handful that will be considered for a biomarker panel), some sort of feature reduction (Sect. 22.4) should be performed to narrow the list of candidate biomarkers down to a more reasonable number. Once the list of proteins has been reduced to those that are likely most useful for downstream classification purposes, unsupervised or supervised learning is performed (Sects. 22.5 and 22.6, respectively).
β-Adrenergic blockade does not impair the skin blood flow sensitivity to local heating in burned and nonburned skin under neutral and hot environments in children.

Objective We tested the hypothesis that propranolol, a drug given to burn patients to reduce hypermetabolism/cardiac stress, may inhibit heat dissipation by changing the sensitivity of skin blood flow (SkBF) to local heating under neutral and hot conditions. Methods In a randomized double-blind study, a placebo was given to eight burned children, while propranolol was given to 13 burned children with similar characteristics (mean±SD: 11.9±3 years, 147±20 cm, 45±23 kg, 56±12% Total body surface area burned). Nonburned children (n=13, 11.4±3 years, 152±15 cm, 52±13 kg) served as healthy controls. A progressive local heating protocol characterized SkBF responses in burned and unburned skin and nonburned control skin under the two environmental conditions (23 and 34°C) via laser Doppler flowmetry. Results Resting SkBF was greater in burned and unburned skin compared to the nonburned control (main effect: skin, P .05) under either condition. Conclusion Therapeutic propranolol does not negatively affect SkBF under neutral or hot environmental conditions and further compromise temperature regulation in burned children.
Optimal Modification and Evolution of Elastic Continuum Structures

The developments reported in this paper relate to the concept of optimal evolutionary remodelling. A variational formulation is presented for the problem of optimal remodel of an arbitrary, given continuum structure, where the modification may be interpreted to represent a strengthening (growth) of or diminishing (resorbtion) from the starting structure. Modification variables have the form of an unrestricted material modulus tensor or a set (mixture) of such tensors. The argument of the isoperimetric constraint is expressed in generalized form, as is the objective. Evolution is simulated as a stepwise process, where each step is determined as an optimal remodel. Both local material properties and load configuration may vary with the process. Necessary and sufficient conditions for the optimal stepwise remodel are identified. Interpretations of the simulation model are compared to known methods for application to growth or degradation in bone.
Imaging the physiological evolution of the ischemic penumbra in acute ischemic stroke

We review the hemodynamic, metabolic and cellular parameters affected during early ischemia and their changes as a function of approximate cerebral blood flow ( CBF) thresholds. These parameters underlie the current practical definition of an ischemic penumbra, namely metabolically affected but still viable brain tissue. Such tissue is at risk of infarction under continuing conditions of reduced CBF, but can be rescued through timely intervention. This definition will be useful in clinical diagnosis only if imaging techniques exist that can rapidly, and with sufficient accuracy, visualize the existence of a mismatch between such a metabolically affected area and regions that have suffered cell depolarization. Unfortunately, clinical data show that defining the outer boundary of the penumbra based solely on perfusion-related thresholds may not be sufficiently accurate. Also, thresholds for CBF and cerebral blood volume ( CBV) differ for white and gray matter and evolve with time for both inner and outer penumbral boundaries. As such, practical penumbral imaging would involve parameters in which the physiology is immediately displayed in a manner independent of baseline CBF or CBF threshold, namely pH, oxygen extraction fraction ( OEF), diffusion constant and mean transit time ( MTT). Suitable imaging technologies will need to meet this requirement in a 10-20 min exam.
Teacher versus peer models.

Female Ss (N=80) observed either a teacher or a peer model (M) demonstrate a motor task with either high or low performance ability. The effects’ of viewing these live performances on S’s subsequent motor performances were examined. After the observation of M, S’s performance in the presence or absence of the observed M was investigated. A Control Group consisting of 20 Ss, viewing no M, was compared to ail other groups for analysis. Results of the M Type × M’s Ability Level × M Presence design indicated that those in the Control Group had significantly lower performances than all other groups on all blocks of trials. In addition, across all trial blocks, S’s performances were enhanced subsequent to having viewed a skillful teacher M. Upon observing M’s demonstration, Ss exhibited increased matching responses and better performances when performing in the presence of M.
Negative capacitance transients in metal-ferroelectric Hf 0.5 Zr 0.5 O 2 -Insulator-Semiconductor (MFIS) capacitors

The subthreshold swing (SS) in MOSFETs is limited to 60 mV/dec change in drain current at room temperature by the Boltzmanr distribution of carriers, thus limiting its operating voltage (V D >SS×log I on /I OFF ). Ferroelectric FETs can achieve sub-60 mV/dec by harnessing the negative capacitance (NC) effect in a Ferroelectric (FE) material, thus enabling low voltage operation [1]. Previous works have reported the direct observation of NC transients in Metal-FE-Metal (MFM) capacitors using epitaxial and polycrystalline ferroelectrics that are directly grown on metal electrodes [2][3][4]. For transistor application, however, FE directly grown on silicon channel with an interfacial oxide layer, such as the Metal-FE-Insulator-Semiconductor (MFIS), represent a more practica] configuration. In this paper, we report on the observation of negative capacitance transient for the first time in the Hafnium Zirconium oxide MFIS capacitor connected in series with a load resistor. We perform systematic experiments to study the influence of series resistance, applied AC voltage amplitude and the role of partial dipole switching on the NC effect.
Determining influential descriptors for polymer chain conformation based on empirical force-fields and molecular dynamics simulations

Abstract Many properties of bulk polymers are closely related to the molecular chain conformation. It is ideal if guidance exists to link molecular features to polymer chain conformation to significantly narrow down the design space. Here, we analyze a series of molecular descriptors derived from empirical force-fields and relate them to single chain conformation characterized by radius of gyration calculated from molecular dynamics simulations. Using data analyses and machine learning techniques, we identify that the weakest dihedral angle, characterized by the energy constants, along the chain backbone is the most influential descriptor determining the single chain radius of gyration.
Evaluation of Anisotropic Properties of Graphite-Epoxy Composites Using Lamb Waves

The obvious advantage of composite materials is in their high strength and stiffness to weight ratios. The anisotropy of the material allows strength to be utilized in a given design direction without the addition of extra weight resulting from strength in unnecessary directions, as is usually the case in isotropic materials. The use of these materials can yield dramatic weight savings over their more conventional metallic counterparts which can reduce fuel consumption and allow for carrying additional fuel or cargo.
Oral history of American science: A forty-year review

L'A. retrace une retrospective des projets interwieves et archives de l'histoire des sciences modernes en se limitant a l'Amerique du Nord et aux developpements scientifiques du XX e siecle
On the Benefits (or Not) of a Clustering Algorithm in Student Tracking

This study proposes a first step toward the automated realization of student tracking, i.e., dividing a class of students into several streams according to criteria such as overall strength, specific abilities, etc. Our study is based on a database of 214 students who took a 64-question multiple choice exam. We examine a family of tracking schemes based on the k means algorithm but differing in feature selection and attribute weighting. We compare these schemes to a naive scheme based solely on overall grades and a human-based scheme that applies k means to content-based features assigned by experienced teachers.
Biomass Conversion to Methane

During the Arab oil embargo of 1973 a world-wide “energy-crisis” was proclaimed, but subsequent experience has revealed that it is really our technological addiction to the use of fluid fuels which is the underlying cause of energy malaise in the industrial world. Although great emphasis is presently being given to the conversion of solid fossil fuels (oil shale, coal, tar sands, and peat) into fluid fuels (“synfuels”), some scientists and policy makers have begun to ask the question: “Why not do the problem right and shift our reliance to renewable sources of fluid fuels rather than perpetuate our dependence on disappearing resources?” This presentation examines the possibility of answering their question affirmatively by using the renewable biomass resource to produce gaseous fuels.
Intelligent Assistive Technology: The Present and the Future

Recent advances in two areas of computer science--wireless sensor networks and AI inference strategies--have made it possible to envision a wide range of technologies that can improve the lives of people with physical, cognitive, and/or psycho-social impairments. To be effective, these systems must perform extensive user modeling in order to adapt to the changing needs and capabilities of their users. This invited talk provides a survey of current projects aimed at the development of intelligent assistive technology and describes further design challenges and opportunities.
WHEN A PATENT DUCTUS ARTERIOSUS IS NOT JUST A DUCTUS

Although isolated patent ductus arteriosus (PDA) is a common cardiac lesion, syndromic PDA from genetic mutations or environmental insult occurs less frequently. Syndromic associations are not always recognized and have clinically significant implications. A 4-week-old, term infant was transferred
Differential Effects of Intrauterine Growth Restriction on the Regional Neurochemical Profile of the Developing Rat Brain.

Intrauterine growth restricted (IUGR) infants are at increased risk for neurodevelopmental deficits that suggest the hippocampus and cerebral cortex may be particularly vulnerable. Evaluate regional neurochemical profiles in IUGR and normally grown (NG) 7-day old rat pups using in vivo 1H magnetic resonance (MR) spectroscopy at 9.4 T. IUGR was induced via bilateral uterine artery ligation at gestational day 19 in pregnant Sprague–Dawley dams. MR spectra were obtained from the cerebral cortex, hippocampus and striatum at P7 in IUGR (N = 12) and NG (N = 13) rats. In the cortex, IUGR resulted in lower concentrations of phosphocreatine, glutathione, taurine, total choline, total creatine (P < 0.01) and [glutamate]/[glutamine] ratio (P < 0.05). Lower taurine concentrations were observed in the hippocampus (P < 0.01) and striatum (P < 0.05). IUGR differentially affects the neurochemical profile of the P7 rat brain regions. Persistent neurochemical changes may lead to cortex-based long-term neurodevelopmental deficits in human IUGR infants.
Assessment of Aortic Stenosis Beyond the Aortic Valve Area

ABSTRACTAortic stenosis (AS) is a common and complex disease for which currently there is no intervention other than aortic valve replacement (AVR). In the current guidelines, AVR is indicated for ...
The Influence of Variable Flows on FIO2 Delivery via Self-Inflating Resuscitation Bags

Background: The appropriate delivery of oxygen therapy during patient resuscitation is a critical task for respiratory therapists. Normal textbook guidelines for resuscitation bags instruct oxygen flows to be set at 10-15 L/min during code blues and rapid responses. This conservative approach to oxygen administration seems to be the cultural norm across classroom and hospital settings. Our staff respiratory therapists found benefit to increasing the oxygen flow to >15 L/min as effective tool to reverse or prevent hypoxia during resuscitations, particularly in patients with high oxygen requirements. Methods: We took our self inflating resuscitation bag (AmbuBag Spur II) and connected its oxygen tubing to an oxygen flow meter (Timeter) which was plugged into the quick connect hospital wall oxygen outlet. The ventilation side of the bag was then connected to a test lung (Bio-Tek VT-2) with an oxygen analyzer (Mini Ox I) installed in the test lung. Respiratory rate timing for hand bagging was set by using a metronome (Metro Timer). Resuscitation bag was immobilized and compressed fully using a hinged manual compressor. Maximum achieved FIO2 was measured with variable flows of 10 L/min, 15 L/min, >15 L/min "top of valve" (with metal ball floating at very top of flow meter), and "full flush" (oxygen flow meter valve completely open). Results: We found a significant increase in measured FIO2 with increased oxygen flows. At 10 L/min, the highest measured FIO2 was 43.2% At 15 L/min, the highest measured FIO2 was 54.5%. At "top of the valve" >15 L/min, the highest measured FIO2 was 74.2%. Lastly, when the flow meter valve was set to "full flush", highest measured FIO2 was 92.2%. This translated into a 113% increase in FIO2 from when going from 10 L/min to full flush. We took a razorblade to one of our resuscitation bags, and after entirely disassembling we discovered the advantage of having a length of corrugated tubing tail that surrounds the oxygen tubing. When flow meter is set to >15 L/min, this tail collects and stores supplemental oxygen that can be drawn from, during vigorous bagging. This study was presented to our Respiratory care leadership and led to our adopting a new clinical practice advisory that supports the delivery of higher oxygen flows when indicated. Conclusions: When using certain self inflating resuscitation bags, our data suggests that increasing the oxygen flow to >15 L/min is an effective way for clinicians to dramatically increase FIO2 delivery. Disclosures: None.
Chapter 16 – Imperfection

Since we now understand that evolution has no innate progressionistic plan or goal, there is no reason to believe that biological “perfection” is ever attainable, nor would we be able to determine when perfection had been achieved. Rather, natural selection results in organisms that are simply better than the competition—since that is all that is required to achieve genetic fitness in populations. Selection also is forced to work with the genes and alleles available. It cannot create de novo new genes with completely new and more perfect phenotypes. Most of evolution is about adjusting the set of genes already present. Selection often cannot quickly eliminate a trait and its associated genes that have become useless—thus vestigial genes and structures are common in most organisms. Sexual selection in some cases results in males burdened with costly ornamentation that reduces survival value, yet increases their attractiveness to females. This combination does make for better fitness, but seems obviously not to be a perfect situation for the males. The genome itself is revealing itself to be an especially complex system filled with useless pseudogenes, vestigial genes, genetic parasites, B chromosomes, and other entities that add little if anything to organismal fitness. With change playing such a significant role in the evolution of life, imperfection to a certain degree is to be expected.
A Case of Hypokalemic Periodic Paralysis in a Young Athlete

Hypokalemic periodic paralysis (HPP) is one of the group muscle disorders that can cause sudden onset paresis or paralysis. It is a quite rare, yet, potentially life-threatening condition that, if appropriately and promptly diagnosed and treated, can be completely reversed. Other forms of periodic paralysis include thyrotoxic periodic paralysis, hyperkalemic periodic paralysis, and Anderson syndrome. We are presenting a case of a young male who presented to the emergency department (ED) with sudden paralysis to shed light on such a diagnosis and on other differential diagnoses.
The use of staples for external ventricular drain catheter fixation: A single-institution experience.

Abstract Background Sutures are conventionally used for external ventricular drain (EVD) catheter fixation, but staples are an appealing alternative as they are quicker and easier to learn. We report our institutional experience with EVD fixation techniques and the patterns of catheter fixation. Methods We conducted a retrospective review of all aneurysmal subarachnoid hemorrhage (aSAH) patients treated in a single US center between 2007 and 2017. Results Out of 307 patients, 217 patients (62.2% female, mean age 59.5 years) met inclusion criteria harboring 268 EVDs. Two main configurations were used for EVD catheter fixation; spiral-shaped EVDs in 139 (51.9%) cases and arciform (C-shaped) EVDs in 129 (48.1%) of the cases. 220 (82.1%) were secured with staples and 48 (17.9%) with sutures. The most common complication was obstruction (n = 43, 16.2%), followed by infections (n = 18, 6.8%). Catheter dislodgements occurred in 16 (5.9%) catheters and 61 (22.8%) required repositioning/replacement. EVD dislodgement rates did not differ between the staples and sutures group, or between the spiral and C-shaped EVDs (p = 0.5 and 0.93, respectively). No cases of catheter perforation by the staples were encountered in our cohort. Conclusion Staples and sutures are equally valid and acceptable methods for EVD fixation with similar dislodgement rates. Scarce data exist in the literature regarding dislodgements, and further studies are needed to address its incidence and the best preventive strategies.
The Process of Forging the Curriculum Review Proposal

In this chapter, the process of securing final faculty approval of the new MBA curriculum is presented. The process effectively began with the CRC’s debriefing of the faculty forum and concluded with passage of three motions at a specially convened faculty meeting in fall 1991. Between these events, the CRC struggled to develop a consensus on the design of a new MBA curriculum.
Basics of Biotechnology

Biotechnology involves the use of living organisms in industrial processes—particularly in agriculture, food processing, and medicine. Biotechnology has been around ever since humans began manipulating the natural environment to improve their food supply, housing, and health. Biotechnology is not limited to humankind. Beavers cut up trees to build homes. Elephants deliberately drink fermented fruit to get an alcohol buzz. People have been making wine, beer, cheese, and bread for centuries. For wine, the earliest evidence of wine production has been dated to c. 6000 BC. All these processes rely on microorganisms to modify the original ingredients. Ever since the beginning of human civilization, farmers have chosen higher yielding crops by trial and error, so that many modern crop plants have much larger fruit or seeds than their ancestors.
A Real-Time Server for Experiments in Nonlinear Control

The Boston University Robotics Laboratory is currently developing a Transputer-based Real-Time Server with workstation interface to act as host for experiments in robotics and the control of mechanical systems. Some of the hardware is based on designs which originated in the Yale Robotics Laboratory. A lab rack populated with XP/DCS boards has been interfaced to a Silicon Graphics IRIS 4D/120 GTX workstation. As far as we know, this is the first time in which an IRIS has been connected to a Transputer network for realtime control applications. The details of the installation are described below together with three working experiments in the control of mechanical systems.
Search for Cooper-pair fluctuations in severely underdoped Y 1 − δ Ca δ Ba 2 Cu 3 O 6 + x films ( δ = 0 and 0.2)

The preformed-pairs theory of pseudogap physics in high-${T}_{C}$ superconductors predicts a nonanalytic $T$ dependence for the $ab$-plane superfluid fraction, ${\ensuremath{\rho}}_{S}$, at low temperatures in underdoped cuprates. We report high-precision measurements of ${\ensuremath{\rho}}_{S}(T)$ on severely underdoped $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6+x}$ and ${\mathrm{Y}}_{0.8}{\mathrm{Ca}}_{0.2}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6+x}$ films. At low $T$, ${\ensuremath{\rho}}_{S}$ looks more like $1\ensuremath{-}{T}^{2}$ than $1\ensuremath{-}{T}^{3∕2}$, in disagreement with theory.
Anxious Anthropologists: The Study of Sex

Thomas Gregor. Anxious Pleasures: The Sexual Lives of an Amazonian People. Chicago: The University of Chicago Press. 1985. 223 pp. $19.95 (paper)
Maintaining soundness in hybrid verification approaches for stateful models: A case study

Formal verification techniques such as model checking (MC) and theorem proving (TP) have found increasingly widespread use in the design of critical digital systems as a means to ensure their functional correctness. However, both MC and TP have their limitations. TP generally requires non-trivial human intervention, and MC is limited by the state explosion problem. The situation for MC is especially daunting for systems with large data components. In these cases, it is common to rely on a model abstraction to make MC feasible. Unfortunately, this may also add inaccuracies to the verification process, rendering it invalid. In this paper, we build upon current research and propose a hybrid verification approach that leverages the automation of MC and the logical soundness of TP to build a highly automated, high confidence verification system. We perform a preliminary investigation of the effectiveness of this method by verifying a random access memory (RAM) model. We also discuss how the lessons learned in this case study can be extended and implemented in a robust verification system to verify other similar systems.
The oxidation of cis- and trans-CHClCHCl

When Cl atoms react with CHClCHCl in the presence of O2 at 31°C, a long-chain oxidation occurs. The products are the geometrical isomer of the starting olefin and CHClO, HCl, CO, and CCl2O. The quantum yields of the oxygen-containing products are the same with both isomers and are Φ{CHClO} = 30, Φ{CO} = 11.7, and Φ{CCl2O} = 1.29. The chlorine atom adds to the olefin and is followed by O2 addition. The reaction then proceeds with k6a/k6b = 19 and k7a/k7 ∼ 0.5, where k7 ≡ k7a + k7b. The CCl2H radical oxidizes to regenerate the chain carrier. O(3P) reacts with CHClCHCl at 25°C with a rate coefficient of 6.6 × 108M−1 sec−1 for trans-CHClCHCl and 2.8 × 108M−1 sec−1 for cis-CHClCHCl. The reaction channels are with k1a/k1 = 0.23 and 0.28, respectively, for the cis and trans compounds. Reaction (1b) occurs < 4% of the time. Reaction (1c) leads to polymer production and presumably, via redissociation, to the geometrical isomer of the starting olefin. In the presence of O2 the same long-chain oxidation is observed as in the chlorine-atom initiated oxidation. The chain-initiating step is
Is the chemical gate of connexins voltage sensitive? Behavior of Cx32 wild-type and mutant channels.

Connexin channels are gated by transjunctional voltage (V j) or CO2 via distinct mechanisms. The cytoplasmic loop (CL) and arginines of a COOH-terminal domain (CT1) of connexin32 (Cx32) were shown ...
Development of Stealth Polymeric Ultrasound Contrast Agents

Previous research in our lab has shown that when injected intravenously, drug-loaded polymeric ultrasound contrast agents (UCAs) accumulate within the liver and spleen likely caused by recognition of the UCA by the complement proteins within the blood and uptake by the mononuclear phagocyte system. This study investigates two means of incorporating polyethylene glycol (PEG), a well-researched molecule used for immune system avoidance, into the shell of UCAs to facilitate avoidance mechanisms. The first route used a PEG-polylactic acid (PLA) copolymer to create the UCAs via a water-oil-water emulsion technique. A second approach used d-α tocopheryl polyethylene glycol 1000 succinate (TPGS) as a surfactant during the creation of UCAs with PLA. The resulting formulations of pegylated UCAs were compared to control UCAs created from PLA and a surfactant solution of polyvinyl alcohol (PVA). The impact of adding PEG on size, surface charge, surface morphology, acoustic enhancement, and UCA stability was determined under simulated body conditions. It was seen that complete replacement of PLA with PEG-PLA or PVA with TPGS did not result in functional UCAs. However, PEG could be added by both means in conjunction with PLA and PVA to create UCAs with minimal changes to properties.
Ultraviolet-resonance raman spectroscopy of the filamentous virus Pf3: interactions of Trp 38 specific to the assembled virion subunit.

The class II filamentous virus Pf3 packages a circular single-stranded DNA genome of ∼6300 nucleotides within a cylindrical capsid constructed from ∼2630 copies of a 44 residue α-helical subunit. The single tryptophan residue (Trp 38) of the capsid subunit is located within a basic C-terminal sequence (...R+WIK+AQFF). The local environment of Trp 38 in the native Pf3 assembly has been investigated using 229 nm excited ultraviolet-resonance Raman (UVRR) spectroscopy and fluorescence spectroscopy. Trp 38 exhibits an anomalous UVRR signature in Pf3, including structure-diagnostic Raman bands (763, 1228, 1370, and 1773 cm-1) that are greatly displaced from corresponding Raman markers observed in either detergent-disassembled Pf3, class I filamentous viruses, most globular proteins, or aqueous l-Trp. An unusual and highly quenched fluorescence spectrum is also observed for Trp 38. These distinctive UVRR and fluorescence signatures together reflect interactions of the Trp 38 side chain that are specific to the ...
Weakly nonlinear wave interactions in multi-degree of freedom periodic structures

Abstract This work presents a multiple time scales perturbation analysis for analyzing weakly nonlinear wave interactions in multi-degree of freedom periodic structures. The perturbation analysis is broadly applicable to (discretized) periodic systems in any dimensional space and with a wide range of constitutive nonlinearities. Specific emphasis is placed on cubic nonlinearity, as dispersion shifts typically arise from the cubic components in nonlinear restoring forces. The procedure is first presented in general. Then, application to the diatomic chain and monoatomic two-dimensional lattice demonstrates, individually, the treatment of multiple degree of freedom systems and higher dimensional spaces. The dispersion relations are modified by weakly nonlinear wave interactions and lead to additional opportunities to control wave propagation direction, band gap size, and group velocity. Numerical simulations validate the expected dispersion shifts. An amplitude-tunable focus device demonstrates the viability of utilizing dynamically-introduced dispersion to produce beam steering that may, ultimately, lead to a phononic superprism effect as well as multiplexing/demultiplexing behavior.
A 6-month, randomized, double-blind, placebo-controlled pilot discontinuation trial following response to haloperidol treatment of psychosis and agitation in Alzheimer's disease.

Objective In patients with Alzheimer’s disease (AD) with psychosis or agitation that respond to haloperidol treatment, to evaluate the risk of relapse following discontinuation.
Test of directional photoionisation models of second harmonic generation in optical fibres

We present a set of experiments in which optical fibres are prepared with three optical fields of different frequencies to produce second harmonic generation. The results obtained are shown to be inconsistent with directional photoionisation models for second harmonic generation in glasses.
Manipulation of Central GABAergic and Dopaminergic Systems Alters Stress Responding in the Rat

Activation of central GABA(A) systems with muscimol has been shown to facilitate stress responding and GABA is known to modulate central dopaminergic activity. To evaluate the possibility that this effect of muscimol may depend upon a dopamine mechanism we have tested the effect of intracerebroventricular coadministration of muscimol and the selective D(1) antagonist SCH 23390 on behaviors evoked by tail pinch stress. When injected by themselves muscimol (1.75 nmol) facilitated stress-evoked oral behavior while SCH 23390 (6-600 nmol) produced a dose-related suppression of oral behavior. Coadministration of muscimol and doses of SCH 23390 selected for producing no (6 and 30 nmol), or marginal (60 nmol), effects on stress responding resulted in a dose-related reversal of the increase in orality seen with muscimol alone. The results are consistent with the notion that stressful stimuli activate central GABA(A) systems which, in turn, enhance dopaminergic neurotransmission.
Embedding Ethical Leadership within and across Organization Levels

We develop and test a model linking ethical leadership with unit ethical culture, both across and within organizational levels, examining how both leadership and culture relate to ethical cognition...
Evolving microprocessors which better meet the needs of automotive electronics

The rather explosive historical progress being made in large-scale integration of semiconductor elements is moving faster than the two or three years lead time needed in the automotive industry to move a new idea into production. By presenting a forecast of what can be done soon at a developmental level, both at the automotive electronic-control level and at the LSI microcomputer single-chip development level, the writer hopes that the next generation of automotive electronics in the early 1980's can be started with a clear picture of the calculated risk-taking involved. Topics discussed are the need for custom microprocessors, input and output information rates, and applications to engine control and instrument panel display control, including the concept of satellite assemblies which exchange information available at remote locations.
Sodium Absorption by Intact Sugar Beet Plants

Sodium absorption by intact sugar beet plants (Beta vulgaris) was found to be mediated by at least two distinct mechanisms when uptake was studied over a wide range of Na and K concentrations. The first mechanism operates at low Na concentrations ( 1 milliequivalent per liter), transporting Na as well as K; but apparently this mechanism is not active for Na absorption in young sugar beet plants up to the 10-leaf stage.
Reading Stances in Mathematics: Positioning Students and Texts.

Abstract This review of recent literature, focusing on the integration of mathematics and reading, highlights three reading stances within mathematics classrooms. The first stance, reading problems, highlights the scope-and-sequence, transmission approach to learning mathematics, where the purpose of reading is to figure out how to solve an immediate mathematical problem. The second stance, reading mathematics, focuses on understanding the language of mathematics and often includes diverse texts. In the third stance, reading life, students extend their mathematical understanding to sociopolitical issues, particularly issues that affect students' daily lives. This review concludes by suggesting a source of text for reading life: Environmental print.
Pathways for transcriptional activation of a glutathione-dependent formaldehyde dehydrogenase gene

The widespread occurrence of glutathione-dependent formaldehyde dehydrogenases (GSH-FDH) suggests that this enzyme serves a conserved function in preventing the cytogenetic and potentially lethal interaction of formaldehyde with nucleic acids, proteins and other cell constituents. Despite this potential role of GSH-FDH, little is known about how its expression is regulated. Here, we identify metabolic and genetic signals that activate transcription of a GSH-FDH gene (adhI) in the bacterium Rhodobacter sphaeroides. Activity of the adhI promoter is increased by both exogenous formaldehyde and metabolic sources of this toxin. Elevated adhI promoter activity in DeltaGSH-FDH mutants implicates formaldehyde or the glutathione adduct that serves as a GSH-FDH substrate, S-hydroxymethylglutathione, as a transcriptional effector. From studying adhI expression in different host mutants, we find that the photosynthetic response regulator PrrA and the trans-acting spd-7 mutation increase function of this promoter. The behavior of a nested set of adhI::lacZ fusions indicates that activation by formaldehyde, PrrA and spd-7 requires only sequences 55 bp upstream of the start of transcription. A working model is presented to explain how GSH-FDH expression responds to formaldehyde and global signals generated from the reduced pyridine nucleotide produced by the activity of this enzyme.
Steady-state microbunching in a storage ring for generating coherent radiation.

Synchrotrons and storage rings deliver radiation across the electromagnetic spectrum at high repetition rates, and free electron lasers (FELs) produce radiation pulses with high peak brightness. However, at present few light sources can generate both high repetition rate and high brightness outside the optical range. We propose to create steady-state microbunching (SSMB) in a storage ring to produce coherent radiation at a high repetition rate or in continuous wave (CW) mode. In this paper we describe a general mechanism for producing SSMB and give sample parameters for EUV lithography and sub-millimeter sources. We also describe a similar arrangement to produce two pulses with variable spacing for pump-probe experiments. With technological advances, SSMB could reach the soft X-ray range (< 10 nm).
Probing the Interfacial Structure of Aqueous Electrolytes with Femtosecond Second Harmonic Generation Spectroscopy

The existence of polarizable anions at the outermost layer of electrolyte solutions has received much recent attention from both theory and experiment, but remains controversial. Anions can be probed directly in the UV via their strong charge-transfer-to-solvent (CTTS) transitions. We have recently described experimental characterizations of enhanced concentrations of several anions at the air−water interface, using the surface-specific technique of second harmonic generation. Here we present a detailed description of the experimental design and methodology used in these experiments, as well as a proof of principle experiment with the known surfactant tetrabutylammonium iodide (TBAI), yielding surface enhancements in excellent agreement with surface tension measurements. Furthermore, we analyze the observed increase in the nonresonant contribution to the SHG response from the water background of alkali halide solutions. The observed change in the water structure of alkali halide (except iodide) solutions ...
Using Shared Savings to Foster Coordinated Care for Dual Eligibles

New federal policy initiatives are promoting organizations that integrate and coordinate care to meet the complex needs of people who are dually eligible for Medicare and Medicaid. The hope is that their health care costs will fall and quality of care will improve.
Changes in type I collagen following laser welding

Selection of ideal laser parameters for tissue welding is inhibited by poor understanding of the mechanism. We investigated structural changes in collagen molecules extracted from rat tail tendon (> 90% type I collagen) after tissue welding using an 808 nm diode laser and indocyanine green dye applied to the weld site. Mobility patterns on SDS-PAGE were identical in the lasered and untreated tendon extracts with urea or acetic acid. Pepsin incubation after acetic acid extraction revealed a reduction of collagen alpha and beta bands in lasered compared with untreated specimens. Circular dichroism studies of rat tail tendon showed absence of helical structure in collagen from lasered tendon. No evidence for covalent bonding was present in laser-treated tissues. Collagen molecules are denatured by the laser wavelength and parameters used in this study. No significant amount of helical structure is regenerated on cooling. We conclude that non-covalent interactions between denatured collagen molecules may be responsible for the creation of tissue welding. © 1992 Wiley-Liss, Inc.