cssi/SciSciGPT-SciSciNet huggingface dataset:
A prevalent focused human antibody response to the influenza hemagglutinin head interface

Novel animal influenza viruses emerge, initiate pandemics and become endemic seasonal variants that have evolved to escape from prevalent herd immunity. These processes often outpace vaccine-elicited protection. Focusing immune responses on conserved epitopes may impart durable immunity. We describe a focused, protective antibody response, abundant in memory and serum repertoires, to a conserved region at the influenza hemagglutinin head interface. Structures of eleven examples, eight reported here, from seven human donors demonstrate the convergence of responses on a single epitope. The eleven are genetically diverse, with one class having a common, IG{kappa}V1-39, light chain. All of the antibodies bind HAs from multiple serotypes. The lack of apparent genetic restriction and potential for elicitation by more than one serotype may explain their abundance. We define the head interface as a major target of broadly protective antibodies with the potential to influence the outcomes of influenza infection.
Effect of Si content on the uniaxial tensile behavior of Mo-Si solid solution alloys

Abstract Recrystallized binary Mo-0.2 wt.% Si (Mo-0.68 at.% Si) and Mo-0.3 wt.% Si (Mo-1.0 at.% Si) alloys and a ternary Mo-0.75 wt.% Si-0.14 wt.% B (Mo-2.5 at.% Si-1.2 at.% B) alloy were tested in uniaxial tension as a function of temperature in vacuum and the results are compared to previous results on recrystallized commercial purity (CP) Mo and a binary Mo-0.1 wt.% Si (Mo-0.34 at.% Si) solid solution alloy. Yield strength increases with increasing Si content at all temperatures examined except at room temperature where the 0.1 wt.% Si alloy demonstrates softening; atomistic simulation confirms this behavior to be associated with Si segregation to the core and the associated ease of kink nucleation. Tensile ductility at room temperature rapidly deteriorates with increasing Si content in solid solution but in the Mo-0.3 wt.% Si solid solution alloy, tensile ductility of ~10% was measured at 300°C and thereafter, it increases rapidly at higher temperatures. Serrated flow occurs in the temperature range 600°C~800°C with the serration amplitude increasing with increasing Si content; atomistic simulation illustrates O trapping by Si in solid solution and subsequent de-trapping/release at higher temperatures that can account for the onset temperature delay of serrated flow in these Mo-Si solid solution alloys relative to commercial purity Mo. The serrated flow phenomenon is accompanied by significant work hardening; the presence of dislocation tangles, dipoles and prismatic loops in specimens fractured above ≥ 700°C accounts for the observed work hardening.
Impacts of phosphorus loading temporal pattern on benthic algae growth in Lake Ontario

Abstract Nuisance growth of the alga Cladophora has been a critical issue in the Laurentian Great Lakes for decades. Although loading of total phosphorus (TP) has been below target values since the 1990s, the nearshore of the lakes still experience Cladophora blooms. This study explores the effects of TP loading temporal pattern on Cladophora growth in Rochester Embayment in Lake Ontario, where Cladophora blooms are frequently observed. Long-term TP loadings from the Genesee River, which is the primary tributary to the embayment, are calculated with a hydrological model, and Cladophora indicators based on beach closures and satellite data are collected for 2008–2017 to analyze the TP loading temporal patterns and their relation with Cladophora abundance. Using time series clustering for both TP loading and Cladophora indicators, it is found that besides total annual TP loading, the timing of high TP loading also plays an important role for Cladophora growth. High TP loading in mid-March to mid-June, compared to that in January to mid-March, is found to produce higher Cladophora abundance in summer. This finding is supported and explained using an integrated hydrodynamic and ecological modeling framework that includes a state-of-the-art Cladophora module. This study suggests that future Cladophora control should consider not only the total annual TP loading mass, but also the temporal loading patterns.
Study Design and Measurement Methods for Data Collection

Many study designs and measurement methods are appropriate for use in studying headache triggers. From observational to experimental, these designs all have strengths and limitations that must be weighed when preparing a trigger assessment study. When applied appropriately, studies of various designs can further the understanding of headache and trigger associations. This chapter introduces common study designs and measurement methods and describes strategies for their successful application.
Popliteal Artery Entrapment within a Tibial Plateau Fracture: A Case Report.

Case Tibial plateau fractures can be associated with arterial injuries or dysvascular limbs, particularly in settings of trauma. Dysvascular limb in the setting of fracture is commonly due to dissection of the artery. Entrapment of the artery within the fracture is rare. We report a 48-year-old man who presented with left popliteal entrapment within a left tibial plateau fracture status-post external fixation and stent placement in the popliteal artery. Conclusion Findings from this case highlight entrapment of an artery as a mechanism of a dysvascular limb in the setting of high-energy lower-extremity fractures and specifically for tibial plateau fractures.
There is a hole in my bucky: perspective on a maverick

This small contribution about Prof. Jan C. (Kees) Hummelen shows a part of his scientific life that involved his stay at UCSB and subsequent developments that were influenced by it. The article concentrates on Kees’ major contributions to fullerene research and to organic materials science, particularly organic electronics.
Steganography in Digital Media: Principles, Algorithms, and Applications

Steganography, the art of hiding of information in apparently innocuous objects or images, is a field with a rich heritage, and an area of rapid current development. This clear, self-contained guide shows you how to understand the building blocks of covert communication in digital media files and how to apply the techniques in practice, including those of steganalysis, the detection of steganography. Assuming only a basic knowledge in calculus and statistics, the book blends the various strands of steganography, including information theory, coding, signal estimation and detection, and statistical signal processing. Experiments on real media files demonstrate the performance of the techniques in real life, and most techniques are supplied with pseudo-code, making it easy to implement the algorithms. The book is ideal for students taking courses on steganography and information hiding, and is also a useful reference for engineers and practitioners working in media security and information assurance.
Non-volatile programmable devices and in-circuit test

Once various obstacles are overcome, board testers can serve as programming stations for in-circuit-writable devices such as FPGAs, microcontrollers, EEPROMs, and flash memories. Manufacturing cost and cycle time can be considerably reduced.
Cooperative Strategies in Non-High-Tech New Ventures: An Exploratory Study

Cooperative strategies are of growing interest in entrepreneurship. Current research focuses on high-tech companies, but less is known about cooperative activities in non-high-tech businesses. Diff...
Isolation and Characterization of a Mutant Colicin E2

Escherichia coli K-12 colicinogenic for Col E2 yielded a mutant, SK95, that carries a nonsense mutation in the colicin structural gene. A derivative of SK95 that carries an as yet unidentified suppressor mutation produces a colicin E2 that is temperature sensitive (TS). This mutant colicin kills sensitive cells at low temperature but not at high temperature; the colicin adsorbs to cells at high temperature but does not kill them unless the temperature is lowered. Unlike normal colicin E2, which adsorbs rapidly to cells, TS colicin E2 adsorbs slowly over a period of several hours. The biochemical target of colicin E2 is deoxyribonucleic acid (DNA). When acid solubilization of DNA was compared in cells treated with either TS or normal colicin E2, striking differences were observed. Cell killing and acid solubilization of DNA by colicin E2 were shown to be separable events under certain conditions. The results are discussed in relation to the mechanism of action of colicin E2.
Hypoglycemia and hypothermia in terminal leukemia.

In 1967, Tashima1 stated that hypoglycemia in leukemia was so rare that "its occurrence in the leukemic patient should suggest an islet cell tumor or a concomitant retroperitoneal tumor." Most of the reports of hypoglycemia in leukemic patients were ascribed to in vitro glycolysis by leukocytes and were designated "artifactual hypoglycemia."2,3 Experimentally the phenomenon had been produced in test mice where lymphatic leukemia grows as a solid tumor.4,5 Hypothermia is an occasional manifestation of hypoglycemia; it is receiving increasing recognition and is considered a useful diagnostic aid.6,7 Its appearance is not dependent on the cause of the hypoglycemia. This patient with acute myelogenous leukemia experienced several episodes of hypothermia and hypoglycemia which responded to intravenous dextrose.
Freire's Message for Social Workers

ABSTRACT This paper re-examines key concepts in Paulo Freire's popular education approach and their compatibility with social work philosophy and practice on the group and community levels. Freire's vision of the field of social work is explored, and two case studies are utilized to illustrate the application of this approach and its promise for community practice at the dawn of a new century.
Time-dependent photolysis of adsorbed molecules using synchrotron radiation: CH3FSi(111)(7 × 7)

Abstract We present the first study to demonstrate photolysis of an adsorbed molecule using monochromatized synchrotron radiation. The system studied was CH 3 F adsorbed on Si(111)(7 × 7) at 30 ± 5 K. A quantum yield of 0.04 ±0.02 was derived for the photolysis of the initially physisorbed molecule, which resulted in the formation of SiF and SiC bonds. The high quantum yield suggests that an indirect mechanism drives the reaction: dissociative electron attachment by secondary photoelectrons.
LUNATE AND PERILUNAR DISLOCATIONS

1. A study of fifty patients with dislocations of the lunate bone or perilunar dislocations has been made. The period of observation was adequate in thirty-eight. 2. The injuries generally occur in young or middle-aged men after unusually severe trauma. 3. Associated injuries are frequent, and the most common of these is damage to the median nerve. 4. In one-third of the cases the nature of the lesion was not initially diagnosed or the initial treatment was inadequate. 5. A dislocated lunate bone may be replaced even at a late stage and even if the displacement is severe so long as there is some soft-tissue attachment. The anterior approach may safely be used for the replacement. 6. The lunate bone may be removed without involving the necessity for arthrodesis of the wrist. 7. Open reduction should be employed for trans-scaphoid dislocations whenever exact realignment and good fixation cannot be achieved by closed methods. 8. Excision of the proximal row of the carpus gives the possibility of salvage of a reasonable degree of function, and may be preferable to arthrodesis or removal of only part of the proximal row.
The Chaste Erotics of Marie d'Oignies and Jacques de Vitry

friends clasped her hand from an excess of spiritual affection because he was very close to her although in his chaste mind he thought no evil he felt the first masculine stirrings rising in him."1 Although the motive for taking her hand seems innocent enough, the moment his hand comes into contact with hers, he no longer sees the two of them as priest and holy woman, as confessor and penitent, but as man and woman, subject to lust and physical attraction. The chances are very good that the priest in the story is indeed the hagiographer, Jacques de Vitry (ca. 1160-1240). Throughout his vita of the late-twelfth, earlythirteenthcentury female mystic, he writes himself in a starring role, often referring to himself in the third person and vaguely as "a certain priest."2 The woman, Marie d'Oignies (d. 1213) of the Liege
Cationic agent contrast-enhanced computed tomography imaging of cartilage correlates with the compressive modulus and coefficient of friction

summary Objective: The aim of this study is to evaluate whether contrast-enhanced computed tomography (CECT) attenuation, using a cationic contrast agent (CA4þ), correlates with the equilibrium compressive modulus (E) and coefficient of friction (m )o fex vivo bovine articular cartilage. Methods: Correlations between CECT attenuation and E (Group 1, n ¼ 12) and m (Group 2, n ¼ 10) were determined using 7 mm diameter bovine osteochondral plugs from the stifle joints of six freshly slaughtered, skeletally mature cows. The equilibrium compressive modulus was measured using a fourstep, unconfined, compressive stress-relaxation test, and the coefficients of friction were determined from a torsional friction test. Following mechanical testing, samples were immersed in CA4þ, imaged using mCT, rinsed, and analyzed for glycosaminoglycan (GAG) content using the 1,9-dimethylmethylene blue (DMMB) assay. Results: The CECT attenuation was positively correlated with the GAG content of bovine cartilage (R 2 ¼ 0.87, P < 0.0001 for Group 1 and R 2 ¼ 0.74, P ¼ 0.001 for Group 2). Strong and significant positive correlations were observed between E and GAG content (R 2 ¼ 0.90, P < 0.0001) as well as CECT attenuation and E (R 2 ¼ 0.90, P < 0.0001). The CECT attenuation was negatively correlated with the three coefficients of friction: CECT vs mstatic (R 2 ¼ 0.71, P ¼ 0.002), CECT vs mstatic_equilibrium (R 2 ¼ 0.79, P < 0.001), and CECT vs mkinetic (R 2 ¼ 0.69, P ¼ 0.003). Conclusions: CECT with CA4þ is a useful tool for determining the mechanical properties of ex vivo cartilage tissue as the attenuation significantly correlates with the compressive modulus and coefficient of friction.
Pulsars as gamma ray sources: Nebular shocks and magnetospheric gaps

I summarize the results of recent research on the structure and particle acceleration properties of relativistic shock waves in which the magnetic field is transverse to the flow direction in the upstream medium, and whose composition is primarily electrons and positrons with an admixture of heavy ions. Shocks which contain heavy ions that are a minority constituent by number but which carry most of the energy density in the upstream medium put ~ 20% of the flow energy into a nonthermal population of pairs downstream, whose distribution in energy space is N(E) α E -2, where N(E)dE is the number of particles with energy between E and E + dE. Synchrotron maser activity in the shock front, stimulated by the quasi-coherent gyration of the whole particle population as the plasma flowing into the shock reflects from the magnetic field in the shock front, provides the mechanism of thermalization and non-thermal particle acceleration. The maximum energy achievable by the pairs is γ±m±c2 = m i c 2 γ 1/Z i , where ; 1 is the Lorentz factor of the upstream flow and Z i is the atomic number of the ions. The shock’s spatial structure contains a series of “overshoots” in the magnetic field, regions where the gyrating heavy ions compress the magnetic field to levels in excess of the eventual downstream value. These overshoots provide a new interpretation of the structure of the inner regions of the Crab Nebula, in particular of the “wisps”, surface brightness enhancements near the pulsar. The wisps appear brighter because the small Larmor radius pairs are compressed and radiate more efficiently in the regions of more intense magnetic field. This interpretation suggests that the structure of the shock terminating the pulsar’s wind in the Crab Nebula is spatially resolved, and allows one to measure ; 1~ 4 × 106, the upstream magnetic field B 1 to be ~ 3 × 10-5 Gauss, as well as to show that the total ion flow is~ 3 × 1034 elementary charges/sec, in good agreement with the total current flow predicted by the early Goldreich and Julian (1969) model. The total pair outflow is shown to be about 5 × 1037 pairs per second, in good agreement with the particle flux required to explain the nebular X—ray source. The energetics of particle acceleration within the magnetospheres of rotation powered pulsars and the consequences for pulsed gamma ray emission are also briefly discussed. The gamma ray luminosity above 100 MeV is shown to scale in proportion to Ė1/2 R, as is in accord with some of the simplest ideas about “polar cap” models. Models based on acceleration in the outer magnetosphere are also briefly discussed.
What is atypia? Use, misuse and overuse of the term atypia in diagnostic cytopathology

The term "atypical" was introduced by the founder of modern cytodiagnosis, Dr. George N. Papanicolaou, to convey a very low suspicion of (pre)malignancy. Despite controversies concerning its ambiguous and imprecise definition and its uncertain optimal use, the term "atypia" has continued to be used in cytopathology, and has recently been increasingly used in standardized nongynecologic cytopathology diagnostic reporting terminologies. Its increasing use suggests that "atypia" continues to be a useful category to fill the gap between what we can recognize as entirely normal (including reactive changes) and what we can recognize as clearly abnormal (premalignant or malignant). However, this diagnosis should be used parsimoniously, since the potential overuse of "atypia" diagnoses can lead to the erosion of clinicians' confidence in cytopathology, their misunderstanding of the cytopathology report, and to an increase the clinicians' diagnostic uncertainty, with negative consequences on patients' satisfaction and wellbeing, and on health care costs. A clinically meaningful, standardized cytodiagnostic category of "atypia" requires a narrow definition, quantitative criteria, agreed-upon reference images, a clear clinical meaning (likelihood of underlying malignancy or premalignancy) and, ideally, well-defined management options. The successful implementation of such a standardized "atypia" diagnostic category requires continuous education of cytology professionals and quality assurance efforts to monitor its use. The interobserver variability and potential excessive use of the diagnosis of "atypia" may be reduced by considering and addressing the major factors involved in its variable use, namely the quality of the sample, the definition of "atypia", the education/training of the cytologist/pathologist, and cytologist/pathologist-related "supracytologic" factors.
Effects of linearly polarized 0.6–1.6 μM irradiation on stellate ganglion function in normal subjects and people with complex regional pain (CRPS I)

Background and Objectives Stellate ganglion blocks are an effective but invasive treatment of upper extremity pain. Linearly polarized red and near-infrared (IR) light is promoted as a safe alternative to this procedure, but its effects are poorly established. This study was designed to assess the physiological effects of this latter approach and to quantitate its benefits in people with upper extremity pain due to Complex Regional Pain Syndrome I (CRPS I, RSD). Study Design/Materials and Methods This was a two-part study. In the first phase, six adults (ages 18–60) with normal neurological examinations underwent transcutaneous irradiation of their right stellate ganglion with linearly polarized 0.6–1.6 μm light (0.92 W, 88.3 J). Phase two consisted of a double-blinded evaluation of active and placebo radiation in 12 subjects (ages 18–72) of which 6 had upper extremity CRPS I and 6 served as “normal” controls. Skin temperature, heart rate (HR), sudomotor function, and vasomotor tone were monitored before, during, and for 30 minutes following irradiation. Analgesic and sensory effects were assessed over the same period as well as 1 and 2 weeks later. Results Three of six subjects with CRPS I and no control subjects experienced a sensation of warmth following active irradiation (P = 0.025). Two of the CRPS I subjects reported a >50% pain reduction. However, four noted minimal or no change and improvement did not reach statistical significance for the group as a whole. No statistically significant changes in autonomic function were noted. There were no adverse consequences. Conclusions Irradiation is well tolerated. There is a suggestion in this small study that treatment is beneficial and that its benefits are not dependent on changes in sympathetic tone. Further evaluation is warranted. Lasers Surg. Med. 32:417–423, 2003. © 2003 Wiley-Liss, Inc.
Preparing Preservice General Educators for Inclusion: A Survey of Teacher Preparation Programs in Illinois

General educators must be prepared at the preservice level to accommodate students with diverse learning needs. The purpose of this study was to evaluate the extent to which undergraduate general educators, enrolled in approved teacher preparation programs in public or private institutions across Illinois, received instruction in inclusion and collaboration. Surveys were sent to instructors who taught the state-mandated course on exceptional children to general educators. Thirty-seven instructors representing 35 institutions responded. It was found that a significant gap existed between what instructors perceived as important for preservice educators to know and the actual degree of emphasis they placed in their course on competencies associated with inclusion and collaboration. Overall, it appeared that preservice general educators received limited information about the concepts and practices of inclusion and collaboration and will require additional information if they are to be prepared adequately to a...
Vapor-liquid-solid and vapor-solid growth of phase-change Sb2Te3 nanowires and Sb2Te3/GeTe nanowire heterostructures.

We report the synthesis and characterization of radial heterostructures composed of an antimony telluride (Sb2Te3) core and a germanium telluride (GeTe) shell, as well as an improved synthesis of S...
POPULATION VARIATION AND HYBRIDIZATION IN SEA-ROCKETS (CAKILE, CRUCIFERAE): SEED GLUCOSINOLATE CHARACTERS'

In a study of intra- and interpopulation variation in seed glucosinolates, remarkable uniformity was found among individuals within the two chemically distinct subspecies of East Coast Cakile edentula. Glucosinolates were used as taxonomic markers in a study of hybridization between ssp. edentula and ssp. harperi where they form mixed populations on the Outer Banks of North Carolina. Thirteen plants with hybrid chemical profiles were detected in a sample of 89 individuals from four populations; the zone of hybridization is narrow, and has persisted for at least eight years. Artificial hybrids of the two subspecies are additive for kinds and intermediate for proportions of seed glucosinolates, and families of F2' s show a range of recombinant chemical profiles. Natural hybridization was confirmed by recovering hybrid and parental types in 47 progeny of three presumptive wild hybrids. Glucosinolate profile characteristics segregated independently of the segregation patterns for fruit length and seed weight. Selection against particular glucosinolate phenotypes is one possible mechanism maintaining this narrow hybrid zone on the Outer Banks.
Mutagenic Effect of Azaserine in Relation to Azaserine Resistance in Escherichia coli

For demonstration of the mutagenic effect of azaserine (mutation from streptomycin dependence to nondependence), higher concentrations of this antibiotic are required with azaserine-resistant Escherichia coli than with the sensitive, parental strain. At barely toxic concentrations of azaserine, however, the mutagenic response of the resistant strain is many times higher than that of the sensitive strain.
Rac in the Act of Forgetting

Forgetting has been thought to occur as a result of the natural decay of the neuronal changes induced by learning or because of interference from other cognitive functions. In this issue, Shuai et al. (2010) find that the small G protein Rac may function as a switch for remembering versus forgetting.
C–H⋯O hydrogen bonding in a 4-fluorobenzoate multilayer induced by silver nanoparticles

Abstract SERS, SEIRA, and DFT calculations showed silver nanoparticles can stimulate C–H⋯O hydrogen bonding in 4-fluorobenzoate ion/n-heptane multilayers. SERS/DFT demonstrated that 4-fluorobenzoic acid (4FBA) adsorbed as a 4-fluorobenzoate (4FBT) monolayer on nanosilver. Ionization of 4FBA to 4FBT occurred in the multilayer when 4FBA was deposited in n-heptane onto nanosilver. Frequency shifts in SEIRA bands of 4FBT COO stretch and n-heptane CH bend modes illustrated a change in the degree of C–H⋯O hydrogen bonding as more 4FBT/n-heptane was adsorbed to the multilayer. This work will influence many research areas such as sensors formed from thin organic layers on metal nanoparticles.
Intravital 2-photon imaging, leukocyte trafficking, and the beating heart

Intravital two-photon microscopy allows for the analysis of single-cell dynamics within intact tissues. As it is well recognized that molecular cues that regulate leukocyte trafficking into inflammatory sites differ between various tissues, it is important to study organ-specific responses. Recently, intravital two-photon microscopy has been expanded to moving organs in the mouse such as beating hearts. Unlike previous experimental approaches to image cardiac tissue explants or isolated perfused heart preparations by two-photon microscopy, intravital imaging accounts for the mechanical force transmitted to vessels by the heartbeat and accurately assesses dynamic leukocyte behavior in the coronary vessels and myocardial tissue. Intravital two-photon imaging of beating hearts is a promising experimental tool that will help elucidate cellular and molecular immune processes that contribute to a variety of cardiovascular diseases.
Functional and aesthetic guidelines for stress-reduced direct posterior composite restorations.

SUMMARY Amalgam has been used in the restoration of structurally compromised posterior teeth for many years. When placing large amalgam restorations, replacement of weak cusps with restorative material is recommended to prevent tooth fracture. This recommendation can be modified with new guidelines using modern adhesive techniques. Semidirect and indirect inlay/onlay composite restorations have progressively replaced amalgam restorations over the past 20 years. Lately, single visit direct resin-bonded composite (RBC) restorations have also been used as a viable alternative to conventional indirect restorations. This paper is intended to introduce a step-by-step protocol for the direct restoration of structurally compromised posterior teeth using RBCs with stress-reducing protocols.
Intracellular pH and the sodium requirement at fertilisation.

Several lines of evidence suggest that ionic messengers are primary agents in the metabolic derepression which occurs at fertilisation. The derepression at fertilisation or partheno-genetic activation of the sea urchin egg occurs in two main phases. The first phase, which triggers the early events of fertilisation, is mediated by transitory increase of intracellular free calcium1–3. The second, which triggers the late events of fertilisation, is mediated by a rise in the intracellular pH (refs 4–6). The transition from the early events of fertilisation of sea urchin eggs to the late events requires a minimal concentration of sodium in the external medium7. External Na+ is required for the acid efflux which follows fertilisation8. Na+ requirement and the acid efflux have been correlated in a hypothesis which proposes that internal protons are exchanged for external Na+ (refs 8, 9). By using pH-sensitive microelectrodes, we have examined the relationship between external Na+ and internal pH more closely. We demonstrate here that the increase of the intracellular pH following egg activation does require external Na+. However, the relative insensitivity of the alkalisation of the egg cytoplasm to large reductions of external Na+ is evidence against the Na–H exchange hypothesis.
A validated new method for nevirapine quantitation in human plasma via high-performance liquid chromatography.

A fully validated and clinically relevant assay was developed for the assessment of nevirapine concentrations in neonate blood plasma samples. Solid-phase extraction with an acid-base wash series was used to prepare subject samples for analysis. Samples were separated by high performance liquid chromatography and detected at 280 nm on a C8 reverse-phase column in an isocratic mobile phase. The retention times of nevirapine and its internal standard were 5.0 and 6.9 min, respectively. The method was validated by assessment of accuracy and precision (statistical values 0.996) and the average recovery was 93% (n = 18). The lower limit of quantification (relative standard deviation <20%) was determined to be 25 ng/mL for 50 microL of plasma, allowing detection of as little as 1.25 ng of nevirapine in a sample. This value represents an increase in sensitivity of up to 30-fold over previously published methods.
A trypsin-resistant heme peptide from cardiac cytochrome c1.

Abstract A tryptic resistant heme peptide has been prepared and purified from cardiac cytochrome c 1 . This purified peptide is not further hydrolyzed by reactions of other proteolytic enzymes, such as pronase. The peptide contains 2 residues each of serine, cysteine and valine, and 1 residue each of alanine, methionine, tyrosine, histidine, arginine, proline, glutamic acid (glutamine) and aspartic acid. The intensity of the absorption spectrum of the peptide has been found to be dependent upon, but the positions of the absorption maxima do not vary with, concentration. The heme peptide does not show multiple splitting of absorption peaks at liquid N2 temperatures as does the intact cytochrome c 1 . However, cyanide rapidly reacts with the peptide and causes significant spectral changes. CD spectra of the peptide exhibit a typical profile of a non-structured heme peptide with positive CD bands in the Soret region and around 250 nm, and a broad negative extreme of 320–360 nm. The similarities and differences between the tryptic resistant heme peptides from cytochromes c 1 and c have been compared.
High-temperature and high-power terahertz quantum cascade lasers

We report the demonstration of terahertz QCLs based on a two-phonon depopulation scheme, intended to improve the high-temperature performance, and also the demonstration of QCLs emitting 250 mW in pulsed mode at 4.3 THz.
Disturbances and Defects in Enamel Development

Ameloblastic disturbances are correlated with defects in enamel. Experimental disturbances created by tetracyclines, fluorides, and antimitotic drugs are emphasized. Cellular alterations are shown to interfere with both matrix production and secretion. Defects in enamel formation are characterized by abnormal crystal size and distribution. Further research in normal and particularly abnormal enamel development is needed to establish: 1. exact mode of matrix secretion and its relation to crystal nucleation and orientation 2. function of maturative ameloblast and its relation to the stratum intermedium and papillary layer during that phase 3. cause for lack of mineralization of matrix, particularly in ectopic areas.
K(+) cycling and its regulation in the cochlea and the vestibular labyrinth.

Potassium (K + ) plays a very important role in the cochlea. K + is the major cation in endolymph and the charge carrier for sensory transduction and the generation of the endocochlear potential. The importance of K + handling in the cochlea is marked by the discovery of several forms of hereditary deafness that are due to mutations of K + channels. Deafness results from mutations of KCNQ4, a K + channel in the sensory hair cells, as well as from mutations of the gap junction proteins GJB2, GJB3 and GJB6 that may facilitate cell-to-cell movements of K + . Deafness results also from mutations of KCNQ1 or KCNE1, subunits of a K + channel that carries K + from strial marginal cells and vestibular dark cells into endolymph. Further, deafness results from mutations of KCNJ10, a K + channel that generates the endocochlear potential in conjunction with the high K + concentration in strial intermediate cells and the low K + concentration in the intrastrial fluid spaces. This review details recent advances in the understanding of K + transport and its regulation in the cochlea and the vestibular labyrinth.
Nonadherence to oral linezolid after hospitalization: A retrospective claims analysis of the incidence and consequence of claim reversals

Abstract Background: Linezolid is available in an oral as well as an intravenous formulation. It is an oxazolidinone antibiotic and is effective in treating resistant gram-positive organisms such as methicillin-resistant Staphylococcus aureus and multidrug-resistant Streptococcus pneumoniae . Objectives: The goals of this study were to identify the incidence of claim reversals for oral linezolid in members who were recently discharged from a hospital and to study the subsequent pattern of health care utilization to quantify the consequences for members who have a reversed linezolid claim. Methods: This study was a retrospective claims analysis of Humana Medicare Advantage Prescription Drug patients who had a claim for oral linezolid after an inpatient discharge between April 1, 2006, and June 30, 2008. The incidence of reversed claims among those with a linezolid prescription was measured as a proxy for medication adherence. Propensity scores were calculated to account for differences in patients' propensity to have a reversed claim. The association of the claim reversal with subsequent expenditures was assessed through 3 multivariate regression models wherein the dependent variables were drug, medical, and total costs for the 60-day period after discharge. The key independent variable was the occurrence of a reversed linezolid claim, and control variables included the propensity score quartiles and other clinical and demographic characteristics. All costs were provided in US dollars and from the year in which they occurred. Results: Of 1046 patients identified (mean [SD] age, 69 [12] years; 51% male), 252 patients (24.1%) had a claim reversal for linezolid. Among these, 125 patients (49.6%) received linezolid within 10 days of the initial reversal, 39 patients (15.5%) received other antibiotics, and 88 patients (34.9%) did not receive any antibiotics. The unadjusted, mean outpatient drug costs were $696 and $2265 for patients with and without a reversal, respectively, whereas mean medical costs were $13,567 and $9355. Multivariable analyses revealed that members who did not receive linezolid after the claim reversal had significantly higher medical expenditures (Wald χ 2 , 8.370; P = 0.004) and lower drug expenditures (Wald χ 2 , 122.630; P 2 , 1.540; P=0.215), however, as the medical savings were partially negated by the higher drug costs. Conclusion: These patients with a reversed outpatient claim for linezolid had lower outpatient drug costs and higher medical costs in the 60-day period after the reversal.
Salmonella typhimurium as a novel RNA interference vector for cancer gene therapy.

Commentary to:Oral administration of attenuated S. typhimurium carrying shRNA-expressing vectors as a cancer therapeuticNan Yang, Xiangying Zhu, Lishan Chen, Shenghua Li, Daming Ren
A cohort cost analysis of lumbar laminectomy—current trends in surgeon and hospital fees distribution

Abstract Background context Spine-related health-care expenditures accounted for $86 billion dollars in 2005, a 65% increase from 1997. However, when adjusting for inflation, surgeons have seen decreased reimbursement rates over the last decade. Purpose To assess contribution of surgeon fees to overall procedure cost, we reviewed the charges and reimbursements for a noninstrumented lumbar laminectomy and compared the amounts reimbursed to the hospital and to the surgeon at a major academic institution. Study design/setting Retrospective review of costs associated with lumbar laminectomies. Patient sample Seventy-seven patients undergoing lumbar laminectomy for spinal stenosis throughout an 18-month period at a single academic medical center were included in this study. Outcome measures Cost and number of laminectomy levels. Methods The reimbursement schedule of six academic spine surgeons was collected over 18 months for performed noninstrumented lumbar laminectomy procedures. Bills and collections by the hospital and surgeon professional fees were comparatively analyzed and substratified by number of laminectomy levels and patient insurance status. Unpaired two-sample Student t test was used for analysis of significant differences. Results During an 18-month period, patients underwent a lumbar laminectomy involving on average three levels and stayed in the hospital on average 3.5 days. Complications were uncommon (13%). Average professional fee billing for the surgeon was $6,889±$2,882, and collection was $1,848±$1,433 (28% overall, 30% for private insurance, and 23% for Medicare/Medicaid insurance). Average hospital billing for the inpatient hospital stay minus professional fees from the surgeon was $14,766±$7,729, and average collection on such bills was $13,391±$7,256 (92% overall, 91% for private insurance, and 85% for Medicare/Medicaid insurance). Conclusion Based on this analysis, the proportion of overall costs allocated to professional fees for a noninstrumented lumbar laminectomy is small, whereas those allocated to hospital costs are far greater. These findings suggest that the current focus on decreasing physician reimbursement as the principal cost saving strategy will lead to minimal reimbursement for surgeons without a substantial drop in the overall cost of procedures performed.
An ultrastructural study on the blood-brain barrier dysfunction following mercury intoxication.

Methyl mercuric chloride (CH3HgCl) was administered in a single intraperitoneal injection to adult male rats at a dosage of 10 mg/kg body weight. Horseradish peroxidase was systemically injected into these animals at various time intervals following methyl mercury administration. Horseradish peroxidase activity as demonstrated by 3,3′-diaminobenzidene conjugation was used as a tracer to study blood-brain barrier dysfunction induced by methyl mercury. Permeation of tracer into the parenchyma of the central nervous system was observed ultrastructurally as early as 4–6 hrs following methyl mercury administration. Examination of capillary regions in the calcarine cortex and cerebellum at this time also revealed many endothelial cells with mitochondrial injury, increased pinocytotic transport of tracer, and in several instances, widening of lateral leaflet spaces without disruption of tight junctions. 6 hrs after the intoxication, many astrocytic end-feet abutting these injured capillaries displayed swelling and tracer accumulation. Horseradish peroxidase activity could be localized within neuronal and glial elements after 10–12 hrs of methyl mercury treatment. A newly developed electron microscopic histochemical technique utilizing an ammonium sulfide reaction was also employed to study the distribution of mercury within the blood-brain barrier structures. Localization of mercury corresponded with observed sites of cellular injury and tracer extravasation. It is believed that the observed blood-brain barrier dysfunction was due to the impairment of endothelial cells and astrocytic end-feet by mercury ions.
Static axial stretching enhances the mechanical properties and cellular responses of fibrin microthreads

Abstract Fibrin microthreads are a platform technology that can be used for a variety of applications, and therefore the mechanical requirements of these microthreads differ for each tissue or device application. To develop biopolymer microthreads with tunable mechanical properties, we analyzed fibrin microthread processing conditions to strengthen the scaffold materials without the use of exogenous crosslinking agents. Fibrin microthreads were extruded, dried, rehydrated and static axially stretched 0–200% of their original lengths; then the mechanical and structural properties of the microthreads were assessed. Stretching significantly increased the tensile strength of microthreads 3-fold, yielding scaffolds with tensile strengths and stiffnesses that equaled or exceeded values reported previously for carbodiimide crosslinked threads without affecting intrinsic material properties such as strain hardening or Poisson’s ratio. Interestingly, these stretching conditions did not affect the rate of proteolytic degradation of the threads. The swelling ratios of stretched microthreads decreased, and scanning electron micrographs showed increases in grooved topography with increased stretch, suggesting that stretching may increase the fibrillar alignment of fibrin fibrils. The average cell alignment with respect to the longitudinal axis of the microthreads increased 2-fold with increased stretch, further supporting the hypothesis that stretching microthreads increases the alignment of fibrin fibrils on the surfaces of the scaffolds. Together, these data suggest that stretching fibrin microthreads generates stronger materials without affecting their proteolytic stability, making stretched microthreads ideal for implantable scaffolds that require short degradation times and large initial loading properties. Further modifications to stretched microthreads, such as carbodiimide crosslinking, could generate microthreads to direct cell orientation and align tissue deposition, with additional resistance to degradation for use as a long-term scaffold for tissue regeneration.
Additive relations and function tables

Abstract We present work with a second grade classroom where we carried out a teaching experiment that attempted to bring out the algebraic character of arithmetic. In this paper, we specifically illustrate our work with the second graders on additive relations, through the children’s work with function tables. We explore the different ways in which the children represented the information of a problem in the form of a self-designed function table. We argue that the choices children make about the kind of information to represent or not, as well as the way in which they constructed their tables, highlight some of the issues that children may find relevant in their construction of function tables. This open-ended format pointed to how they were understanding and appropriating tables into their thinking about additive relations.
Voltage quantization by ballistic vortices in two-dimensional superconductors.

The voltage generated by moving ballistic vortices with a mass ${\mathit{m}}_{\ensuremath{\nu}}$ in a two-dimensional superconducting ring is quantized, and this quantization depends on the amount of charge enclosed by the ring. The quantization of the voltage is the dual to flux quantization in a superconductor, and is a manifestation of the Aharonov-Casher effect. The quantization is obtained by applying the Bohr-Sommerfeld criterion to the canonical momentum of the ballistic vortices. The results of this quantization condition can also be used to understand the persistent voltage predicted by van Wees for an array of Josephson junctions.
Theory of stimulated Raman scattering with broad-band lasers

Abstract : The authors have extended the theory of stimulated Raman scattering to include the effects of laser bandwidths, in both the transient and steady-state regimes. The case of two interacting laser beams, a pump laser and a probe (Stokes) laser, is treated. Using the phase-diffusion model for laser bandwidth, the authors demonstrate that in the absence of dispersion, the forward Raman gain is essentially independent of the laser bandwidths in the high-gain limit, while in the low gain limit the gain coefficient is inversely proportional to the sum of the bandwidths. It is further shown that when the pump-laser bandwidth is much larger than the linewidth of the Raman medium, the stimulated Stokes output assumes the same spectrum as the pump laser in the high-gain limit. A possible interpretation of these results is discussed assuming a phase-locking of the Stokes phase to the fluctuations in the pump-laser phase, due to the nonlinear interaction of the two beams through the Raman medium.
Energy and Performance-Aware Task Scheduling in a Mobile Cloud Computing Environment

Mobile cloud computing (MCC) offers significant opportunities in performance enhancement and energy saving in mobile, battery-powered devices. An application running on a mobile device can be represented by a task graph. This work investigates the problem of scheduling tasks (which belong to the same or possibly different applications) in an MCC environment. More precisely, the scheduling problem involves the following steps: (i) determining the tasks to be offloaded on to the cloud, (ii) mapping the remaining tasks onto (potentially heterogeneous) cores in the mobile device, and (iii) scheduling all tasks on the cores (for in-house tasks) or the wireless communication channels (for offloaded tasks) such that the task-precedence requirements and the application completion time constraint are satisfied while the total energy dissipation in the mobile device is minimized. A novel algorithm is presented, which starts from a minimal-delay scheduling solution and subsequently performs energy reduction by migrating tasks among the local cores or between the local cores and the cloud. A linear-time rescheduling algorithm is proposed for the task migration. Simulation results show that the proposed algorithm can achieve a maximum energy reduction by a factor of 3.1 compared with the baseline algorithm.
Condom use to prevent incident STDs: the validity of self-reported condom use.

Studies of sexual behavior and of interventions designed to reduce human immunodeficiency virus risk usually depend on self-report. Validation of self-reported condom use measures has not been previously reported in an urban population at high risk for sexually transmitted diseases (STDs) and human immunodeficiency virus. A prospective cohort study was performed in subjects recruited from STD clinics in Baltimore. At enrollment a questionnaire was administered that assessed human immunodeficiency virus risk factors and STD history and used a retrospective calendar to assess sexual events and condom use over the previous 30 days. Clinical evaluation was performed for STDs. A follow-up 3 months later the same procedures were repeated. Incident STDs at follow-up were defined as new culture or serologically documented diagnoses of gonorrhea chlamydia syphilis or trichomoniasis. In the 323 male and 275 female (total = 598) subjects who completed a follow-up visit 21% reported using condoms for every act of sexual intercourse over the previous 30 days 21% reported occasionally using condoms and 59% reported not using condoms. At follow-up 21% of subjects had new incident gonorrhea chlamydia syphilis or trichomoniasis. 15% of the men who were "always" condom users had incident STDs compared with 15.3% of "never users;" 23.5% of women who were "always" users had incident STDs compared with 26.8% of "never" users. In this high-risk population self-reported condom use is not associated with lower STD incidence. This finding suggests that self-reported condom use measures even in a research setting may be subject to substantial reporting bias. (authors)