cssi/SciSciGPT-SciSciNet huggingface dataset:
A fast immersed boundary method using a nullspace approach and multi-domain far-field boundary conditions

We report on the continued development of a projection approach for implementing the immersed boundary method for incompressible flows in two and three dimensions. Boundary forces and pressure are regarded as Lagrange multipliers that enable the no-slip and divergence-free constraints to be implicitly determined to arbitrary precision with no associated time-step restrictions. In order to accelerate the method, we further implement a nullspace (discrete streamfunction) method that allows the divergence-free constraint to be automatically satisfied to machine roundoff. By employing a fast sine transform technique, the linear system to determine the forces can be solved efficiently with direct or iterative techniques. A multi-domain technique is developed in order to improve far-field boundary conditions that are compatible with the fast sine transform and account for the extensive potential flow induced by the body as well as vorticity that advects/diffuses to large distance from the body. The multi-domain and fast techniques are validated by comparing to the exact solutions for the potential flow induced by stationary and propagating Oseen vortices and by an impulsively-started circular cylinder. Speed-ups of more than an order-of-magnitude are achieved with the new method.
Induced abortion: source of guilt or growth?

With the Supreme Court recognition of abortion as a matter between a woman and her physician, the commitment of the medical profession to the highest standards of total patient care requires greater consideration of the psychological component in the abortion experience than has heretofore been provided. This paper suggests providing social work service—individual, family, or group—in all obstetric-gynecologic facilities.
Investigation of competing interactions in alkali metal ion–acetone–water clusters

Abstract Competitive interactions were investigated in M+(Acetone)n(H2O)m cluster ions for M = Na and K. Different [n, m] combinations were characterized by infrared predissociation spectroscopy. When n + m = 4 for Na+, shifts in the water O–H stretch modes demonstrate that the acetone weakens the ion–water interaction but does not alter the solvent configuration around the ion. For K+ at this size, the acetone weakens the ion–water interaction to the extent that hydrogen bonds are formed. When n + m = 5 for both ions, O–H frequency shifts indicate that hydrogen bonds in the immediate ionic environment are weakened by the presence of acetone.
The GaAs(110)-oxygen interaction: A LEED analysis. II

The room temperature LEED study of the GaAs(110)-oxygen interaction has been further investigated. The structure model proposed by Kahn et al. (Surface Sci. 87 (1979) 325) for the oxygen exposed surface has been tested on several additional diffracted beam via single scattering theory. The study of the LEED pattern for the transition exposures (103–108 L) illustrates the evolution of the surface with increasing oxygen exposure. The LEED pattern was also observed for high (1014 L) oxygen exposures. Furthermore, the experiment was repeated using excited oxygen and according changes in the kinetics of the reaction (100 times faster) were recorded. This final result seems to confirm the dissociative-defect-induced character of the reaction.
A REACTION BETWEEN PHEOPHYTIN and CHLOROPHYLL ADSORBED TO POLYETHYLENE-TETRADECANE PARTICLES*

— When chlorophyll is adsorbed to polyethylene-tetradecane particles along with ligating amphiphiles, and pheophytin is present also, a slow but irreversible photobleaching of the chlorophyll is observed in suspensions of the particles in aqueous media. It is suggested that the reaction starts by transfer of an electron from singlet excited chlorophyll to pheophytin and concludes by hydration and reduction of the chlorophyll radical cation.
Zn + implanted silicon waveguide photodiodes for on-chip mid-infrared detection

We present the first experimental demonstration of Zn + implanted Si waveguide photodiodes for 2.2-2.4 μm operation. Preliminary responsivities > 65 mA/W are measured, suggesting suitability for on-chip sensing and communications applications in the mid-infrared.
Commissural connections mediate inhibition for the computation of interaural level difference in the barn owl.

In the barn owl (Tyto alba), the posterior nucleus of the ventral lateral lemniscus (VLVp) is the first site of binaural convergence in the pathway that processes interaural level difference (ILD), an important sound-localization cue. The neurons of VLVp are sensitive to ILD because of an excitatory input from the contralateral ear and an inhibitory input from the ipsilateral ear. A previously described projection from the contralateral cochlear nucleus, can account for the excitation. The present study addresses the source of the inhibitory input.
Two-pion exchange in the nucleon-nucleon potential

Abstract The two-pion-exchange potential is calculated using experimental ππ , π N and eN information and compared with the Hamada-Johnston and deTourreil-Sprung phenomenological potentials. The calculated potential is found to be in very satisfactory agreement with the phenomenological values at radii greater than 1.2 to 1.5 fm except in the isospin-zero spin-orbit case. The potential is somewhat sensitive to the low-energy I = J =0 ππ interaction, which is still experimentally uncertain.
Identification of a primate cytomegalovirus group-common protein antigen.

Abstract A monospecific rabbit antiserum has been prepared to the denatured 145K major capsid protein of strain Colburn cytomegalovirus (CMV). Using this antiserum to analyze proteins electrophoretically transferred to nitrocellulose, it was found that infected cell preparations from all primate CMVs examined contain a single cross-reactive protein band that ranged in molecular weight from 144K to 153K, depending upon the isolate. No reactivity was observed when similar preparations of herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), and herpes zoster virus (HZV) were tested, suggesting that this antiserum may be CMV group-specific. A second antiserum prepared to the denatured Colburn 66K matrix protein was found to be more selective in its reactivity toward other simian CMVs, and without reactivity to human CMV preparations.
Which teen mothers choose Norplant

Purpose: The objective of this study was to determine if there are sociodemographic differences between adolescent mothers who choose to use Norplant after delivery and those who do not. We hypothesized that those adolescent mothers who are at highest risk for repeat adolescent pregnancy are at least likely to select Norplant as a postpartum contraceptive. Methods: We prospectively compared the prevalence of epidemiologic risk factors for repeat adolescent pregnancy in a group of 187 consecutively delivered 13–18year-olds who were enrolled in a comprehensive, multidisciplinary, adolescent-oriented maternity program. The study subjects were interviewed at delivery; 100 subsequently had a Norplant inserted (Norplant users). Student's t -tests and chi-square analyses were used to compare Norplant users and refusers. Results: We found no statistically significant differences between Norplant users and refusers with regard to: age, race, Medicaid, or marital or school status. Compared to Norplant refusers, Norplant users were less likely to be primiparous (79% compared to 90%; p = .04) and more likely to have poor school grades (20% compared to 7%; p = .001). Norplant users were more likely to state that they had had trouble remembering to use contraceptives in the past (32% compared to 14%; p = .005). Conclusions: These data do not support the study hypothesis and are encouraging because they suggest that Norplant may reduce repeat pregnancy among adolescent parents.
Eigenvalues and separation in graphs

Abstract Consider a one-to-one map f : V ( G )→ V ( H ) of Graphs G and H , where | G |⩽| H |. We let | f |=min{dist H (f(x), f(y)):xyeE(G)} , where dist H denotes distance in H . Now define sep( G , H ), the separation of G into H , to be the maximum of | f | over all such maps f . Using the Kronecker product of matrices, we develop a method for computing, in certain favorable cases, the set of eigenvalues of graphs of the form ( G × H )( k ). Here G × H refers to the usual graph product, and S ( k ) (for a graph S ) is the graph obtained from S by joining two points of V ( S ) by an edge if and only if they are at distance at most k in S . Let Q ( n ) and C n × C n denote the n -dimensional cube and the n × n “discrete torus” respectively, and λ min ( S ) the smallest eigenvalue of a graph S . We apply our method to analyze λ min ( Q ( n )( k )) and λ min (( C n × C n )( k )), obtaining exact values for certain k and asymptotically optimal lower bounds for others. Combining these results with one of the results of Alon and Milman, we obtain bounds for the edge isoperimetric problem in the graphs Q ( n )( k ) c and ( C n × C n )( k ) c , where S c denotes the graph obtained from a graph S by joining two vertices if and only if they are not joined in S . As a corollary we obtain functions b(k, p)[c(k, p)] such that if a graph G on p points and q edges satisfies q > b(k, p)[q > c(k, p)] , then sep( G , Q ( n ))⩽ k [sep( G , C n × C n ⩽ k ].
40 Gbit/s AlGaAs/GaAs HBT 4:1 multiplexer IC

An experimental high speed 4:1 multiplexer integrated circuit capable of handling four simultaneous data channels without external delay lines is presented. The experimental circuit features an inherently fast two-stage configuration, with operation up to 40 Gbit/s demonstrated in an advanced AlGaAs/GaAs heterojunction bipolar technology. The system clock frequency is half the bit rate with only one additional self-generated internal clock necessary. A unique circuit topology has been chosen, which acquires, delays, regenerates, and retimes the incoming data. >
Vaginal erosion of cadaveric fascia lata following abdominal sacrocolpopexy and suburethral sling urethropexy.

The aim of this paper is to report vaginal erosion of cadaveric fascia lata used for abdominal sacrocolpopexy and suburethral sling urethropexy. The charts of patients who underwent abdominal sacrocolpopexy or suburethral sling urethropexy between March 1994 and February 1999 were reviewed for perioperative data. In 47 cases of abdominal sacrocolpopexy or suburethral sling, 32 utilized cadaveric fascia lata, with 11 for sacrocolpopexy and 22 for suburethral sling. Vaginal erosion of cadaveric fascia lata graft was noted in 5 (23%) following sling procedure and 3 (27%) following sacrocolpopexy, diagnosed a mean of 36.8 days (þ 7.1, range 27–45) following surgery. These women were treated conservatively with estrogen vaginal cream, and both vaginal and oral antibiotics. Four of the 8 (50%) underwent excision of the exposed graft and reapproximation of the vaginal edges under local anesthesia, whereas the remainder responded to medical therapy alone. None of the patients experienced recurrence of vaginal vault prolapse or urinary incontinence following graft erosion. Comparison of women with vaginal erosion of cadaveric fascia lata to those without revealed an association with perioperative febrile morbidity (P = 0.04), but not with age, hormonal or insurance status, body mass index, history of diabetes mellitus or smoking, length of surgery, estimated blood loss, change in hematocrit, or other perioperative complications. Vaginal erosion of cadaveric fascia lata utilized for abdominal sacrocolpopexy and suburethral sling was noted in 25% of our patients and may have an infectious etiology. Conservative treatment with antibiotics and estrogen is effective, but removal of exposed graft with vaginal closure may be necessary.
Modeling the effect of a disease on culling: an illustration of the use of time-dependent covariates for survival analysis.

This study demonstrated five different approaches, with and without time-dependent covariates, to determine the effect of disease on culling. It was also of interest to determine whether the time of the disease had an effect on subsequent culling (i.e., whether disease should be treated as a time-dependent covariate). To this purpose, five separate models were studied: Models 1 through 4 were Cox proportional hazards models, and Model 5 was a Weibull model. Model 1 treated disease as a binary, time-independent covariate. Model 2 treated disease as a time-dependent covariate, and one change of status was assumed to occur at the time of disease. Model 3 also assumed that one change in status occurred at the time of disease, but the effect of that change was assumed to be different depending on when the disease occurred. Models 4 (Cox) and 5 (Weibull) assumed an interaction between the occurrence of disease (time of disease) and the occurrence of culling (time of culling). As an illustration, the effect of mastitis on culling was studied for 2998 Holstein dairy cows in 10 herds. Parity and previous 305-d milk yield were also included as covariates; the data were stratified by herd. For all models, mastitis was a significant factor for culling. The significance tests for the estimates from Models 4 and 5 demonstrated that the hazard of culling differed for different stages of lactation, depending on when mastitis had occurred and when its effect on culling occurred; that is, time dependence exists between time of mastitis and time of culling.
Two novel point mutations in the long‐range SHH enhancer in three families with triphalangeal thumb and preaxial polydactyly

Spatio-temporal expression of sonic hedgehog (SHH) is driven by a regulatory element (ZRS) that lies 1 Mb upstream from SHH. Point mutations within the highly conserved ZRS have been described in the hemimelic extra toes mouse and in four families with preaxial polydactyly [Lettice et al., 2003]. Four North American Caucasian families were identified with autosomal dominant triphalangeal thumb. DNA from 20 affected and 36 unaffected family members was evaluated by sequence analysis of a 774-bp highly conserved ZRS contained within LMBR1 intron 5. Mutations within ZRS were identified in three of four families. In pedigree A and C, a novel A/G transition was identified near the 5′ end of ZRS at bp 739 that segregated with disease or carrier status. Pedigree A, described previously [Dobbs et al., 2000], is a large family with 19 affected members who exhibit a milder phenotype, including predominantly triphalangeal thumbs and low penetrance (82%) relative to other families. Pedigree C is a small family with two affected family members with triphalangeal thumb, and one affected with both triphalangeal thumb and preaxial polydactyly. A novel C/G mutation at bp 621 was identified in pedigree B that segregated with the disease in all four affected individuals who manifested both preaxial polydactyly and triphalangeal thumb. Both mutations alter putative Cdx transcription factor binding sites. Mutations within ZRS appear to be a common cause of familial triphalangeal thumb and preaxial polydactyly. A genotype/phenotype correlate is suggested by pedigree A, whose mutation lies near the 5′ end of ZRS; this family demonstrates a higher rate of nonpenetrance and milder phenotype. However, modifier genes may be contributing to the milder phenotype in this family. © 2006 Wiley-Liss, Inc.
Retrovirus Reverse Transcriptases Containing a Modified YXDD Motif

The YXDD motif, where X is a variable amino acid, is highly conserved among various viral RNA-dependent DNA polymerases. Mutations in the YXDD motif can abolish enzymatic activity, alter the processivity and fidelity of enzymes and decrease virus infectivity. This review provides a summary of the significant documented studies on the YXDD motif of HIV-1, simian immunodeficiency virus, feline immunodeficiency virus and murine leukaemia virus and the impact of mutation that this motif has had on viral pathogenesis and drug treatment.
Phosphorus, calcium, and magnesium fertilization effects on upland rice in an ultisol

Abstract Acid‐related soil infertility is the major constraint to crop production on low‐activity clay soils in the tropics. We investigated the role of phosphorus (P), calcium (Ca), and magnesium (Mg) in alleviating the acid‐related fertility problem in upland rice on an Ultisol in the humid forest zone of West Africa. A field experiment was conducted in 1994 under rainfed condition to determine the response of an acid‐tolerant, upland rice cultivar (WAB 56–50) to the application of P, Ca, and Mg nutrient combinations. Phosphorus alone or in combination with Ca and Mg significantly increased yield and agronomic and physiological P efficiencies and improved harvest index of the crop. Application of Ca and Mg alone or together had a non‐significant effect on yield, elemental composition of plant tissue at tillering, and the uptake of macro‐ and micronutrients at harvest. The results indicate that P deficiency was the most important nutrient disorder in the Ultisol and that the application of Ca and Mg as p...
Causes of readmission after operation for congenital heart disease.

Background Readmission after operations for congenital heart conditions has significant implications for patient care. Readmission rates vary between 8.7% and 15%. The aim of this study was to determine the incidence, causes, and risk factors associated with readmission. Methods 811 consecutive patients undergoing operations for congenital heart conditions were analyzed. Readmission was defined as admission to any hospital within 30 days of discharge for any cause. Demographic, preoperative, operative, and postoperative variables were evaluated. Univariate comparisons were made between the nonreadmission and readmission groups, and multivariate logistic regression analysis was made to determine independent risk factors for readmission. Results There were a total of 92 readmissions in 79 patients (9.7%). The reasons included cardiac (36, 39%), pulmonary (20, 22%), gastrointestinal (13, 14%), infectious (20, 22%), and other adverse events (2, 2%). Patients with either single-ventricle palliation or nasogastric feeding accounted for 40 (50%) readmissions. On univariate analysis, there were significant differences between readmitted and nonreadmitted patients in relation to patient age, chromosomal abnormality, mortality risk score, duration of mechanical ventilation, postoperative length of stay, single-ventricle physiology, and nasogastric feeding at discharge (p Conclusions The incidence of readmission after operations for congenital cardiac conditions remains high. Efforts focusing on patients with single-ventricle palliation and those with preoperative arrhythmia, prolonged postoperative length of stay and nasogastric tube feeding at discharge may be particularly beneficial.
Simple Methodology for Syntheses of Porphyrins Possessing Multiple Peripheral Substituents with an Element of Symmetry

New methodology was developed for synthesis of regiochemically pure porphyrins with D2h symmetry (e.g. 9) via tetramerization reactions involving two different pyrroles. The two pyrrole components ...
Continuing gastric secretion after insulin hypoglycemia despite glucose injection.

In gastric fistula dogs actively secreting under the influence of insulin hypo-glycemia, the injection of 25 gm. glucose, I.V., 30 min. after injection of insulin, reduced acid and pepsin output by about 60–65%, but only for 45 min. In other experiments, glucose injected 90 min. after injection of insulin reduced acid by 35% but did not reduce pepsin secretion. This suggests that the response of the gastric secretory vagus to insulin is not a simple all-or-none mechanism related solely or even critically to the concentration of glucose in the blood or brain.
High-frequency skywave radar measurements of hurricane anita.

We tracked and monitored hurricane Anita over a 5-day period by using the SRI-operated Wide Aperture Research Facility (WARF) high-frequency skywave radar. The WARF-derived positions for Anita agreed to within +/- 19 kilometers of the coincident temporal positions along the National Hurricane Center's smooth track. Hurricane Anita passed near the open ocean-moored buoy EB-71 of the National Oceanic and Atmospheric Administration, and measurements of wind direction, wind speed, and significant wave height made during this period at the WARF and in situ at the buoy showed agreement of 7 degrees , 0.4 meter per second, and 0.5 meter, respectively. The WARF estimates of longshore coastal surface currents showed good agreement with measurements made at a moored current meter.
Monochromator crystal mounting stage

An insertion device beamline at the Advanced Photon Source had received a second insertion device “undulator A” and consequently needed an upgrade of the optics. The decision to use diamond optics required a mechanical modification of the double crystal monochromator and its crystal alignment stages. Specifications for the tilt alignment accuracy are developed. A crystal alignment stage with independent tilt and translation is described. A new crystal holder was developed, which reduces the temperature of the diamond crystal by over 100 °C and allows for strain-free mounting.
Corticosteroids inhibit the generation of lymphokine-activated killer activity in vitro.

In phase-I clinical trials of adoptive immunotherapy using lymphokine-activated killer (LAK) cells plus recombinant interleukin-2 (rIL-2) (Cetus) for the treatment of malignant glioma, we observed that blood mononuclear cells (MNC) from patients dependent on dexamethasone for management of cerebral edema produced substantially less LAK activity as compared to MNC of normal blood donors or glioma patients not receiving steroid therapy. Therefore, we examined the in vitro effects, brought about by therapeutically attainable concentrations of various corticosteroids, on the proliferative response, production of γ interferon (IFN-γ), and induction of LAK activity from blood MNC of normal donors. Incubation in media containing rIL-2 (1000 U/ml) with either dexamethasone, hydrocortisone, methylprednisolone, or prednisolone profoundly affected all of these parameters. First, while 0.01 μg/ml of either dexamethasone or hydrocortisone caused a slight enhancement of the mitogenic response of lymphocytes to phytohemagglutinin, a dose-dependent decline occurred as concentrations increased to 10 μg/ml. The addition of prednisolone and methylprednisolone elicited a dose-dependent inhibition of lymphocyte proliferation over the entire concentration range tested. At 0.1 μg/ml or higher, dexamethasone, hydrocortisone, methylprednisolone and prednisolone significantly (P<0.02) inhibited the production of IFN-γ: respectively 18.9%, 4.4%, 2.2%, and 12.3% of the IFN-γ produced by MNC in the absence of steroids. All four corticosteroids inhibited the induction of LAK activity. Compared to MNC that had been incubated with 1000 U/ml rIL-2 alone, MNC cultured with rIL-2 and 10 μg/ml either dexamethasone or prednisolone demonstrated significantly lower cytotoxicity (P<0.05) for the natural-killer-cell-resistant cell line, Daudi. Culturing MNC with hydrocortisone had a more dramatic result, causing a significant decline (P<0.01) in lytic activity at both 1.0 μg/ml and 10 μg/ml, while incubation with methylprednisolone produced a significant drop (P<0.02) in LAK-mediated cytotoxicity at 0.1 μg/ml as well as 1.0 μg/ml and 10 μg/ml. When cytotoxicity was expressed as lytic units per million effectors, a dose-response decline in lytic activity was once again apparent, with hydrocortisone, methylprednisolone and prednisolone showing significant inhibition (P<0.05) at both 1.0 μg/ml and 10 μg/ml and dexamethasone at 10 μg/ml (P<0.01). These results indicate that corticosteroids commonly used in the management of cerebral tumors and other malignancies inhibit induction of LAK activity in vitro, and this may explain why it is often difficult to generate LAK activity from blood MNC of patients who are receiving chronic steroid therapy.
Wage Negotiation under Good Faith Bargaining

We study the wage negotiation model of Haller and Holden (1990) and Fernandez and Glazer (1991) under the "Good Faith Bargaining" (GFB) rule, where a party may not demand more than it has previousl...
The importance of race in medical student performance of an AIDS risk assessment interview with simulated patients

Introduction This study was done to ascertain the effect of race on medical student‐patient communication. The primary hypothesis was that interviewing performance scores would be higher when race of student and race of simulated patient instructor (SPI) were concordant than when they were discordant. Methods Data obtained from student interactions with four Caucasian and four African American female SPIs participating in a case involving an AIDS risk assessment interview were analysed. Performance was assessed using two instruments: an 8-item behaviourally anchored interviewing skills scale and a 14-item checklist reflecting content relevant to sexual behaviour and AIDS risk. SPI groups were comparable and SPIs were trained to a high level of inter-rater reliability. Students (24 African American and 180 non-African American) were assigned to SPIs based on the spelling of the student’s name. Performance was scored independently at the conclusion of each interview by both the SPI and the student her/himself. Results African American students had lower scale scores than non-African American students in interactions with Caucasian (but not African American) SPIs; and all student scores, both on the skills scale and the content checklist, were higher with African American than with Caucasian SPIs (as assessed by both SPI and student). Women students had higher scores than men. Conclusions Race of SPI has an influence on student performance of an AIDS risk assessment interview. Further studies focusing on racial interactions in the medical interview are required. It appears that race of SPI may need to be accounted for in the development and interpretation of SPI-based clinical competence exams.
A computerized tomography system for transcranial ultrasound imaging

Hardware for tomographic imaging presents both challenge and opportunity for simplification when compared with traditional pulse-echo imaging systems. Specifically, point diffraction tomography does not require simultaneous powering of elements, in theory allowing just a single transmit channel and a single receive channel to be coupled with a switching or multiplexing network. In our ongoing work on transcranial imaging, we have developed a 512-channel system designed to transmit and/or receive a high voltage signal from/to arbitrary elements of an imaging array. The overall design follows a hierarchy of modules including a software interface, microcontroller, pulse generator, pulse amplifier, high-voltage power converter, switching mother board, switching daughter board, receiver amplifier, analog-to-digital converter, peak detector, memory, and USB communication. Two pulse amplifiers are included, each capable of producing up to 400Vpp via power MOSFETS. Switching is based around mechanical relays that allow passage of 200V, while still achieving switching times of under 2ms, with an operating frequency ranging from below 100kHz to 10MHz. The system is demonstrated through ex vivo human skulls using 1MHz transducers. The overall system design is applicable to planned human studies in transcranial image acquisition, and may have additional tomographic applications for other materials necessitating a high signal output.
Toxicity effects of latex gloves on boar spermatozoa.

Abstract It is known that several materials used in semen collection have been found to be detrimental to spermatozoal motility. In this study, examinations for toxic effects of latex and vinyl gloves, used with and without talcum powder on boar spermatozoa, were performed. Ten boars of known fertility with ≥80% sperm motility were divided into two groups (n = 5 boars each) for in vitro and in vivo studies. In the in vitro study, semen was collected from each of the five boars and was divided into five separate aliquots (5 ml each). One aliquot from each of the boars remained as the control, while the remaining aliquots were divided into individual treatments exposing the semen to a l cm 2 piece of latex or vinyl glove with or without talcum powder. In the in vivo experiment, semen from each of the five boars was collected using a gloved hand. During collection, the first half of the sperm-rich fraction was collected into a filtered sterile container, while the second half of the fraction was allowed to run through the palm of either a latex or vinyl powdered glove prior to collection in the container. In both experiments, semen sample motility was assessed by two independent observers at 1 minute after exposure. Results of both experiments consistently showed a significant (P 0.05) in motility was observed between the control semen and the semen exposed to talcum powdered vinyl gloves. These results show that latex gloves are detrimental to boar spermatozoa. Therefore, it is suggested that when collecting boar semen vinyl gloves should be used.
Comparisons of the Educational Value of Distance Delivered versus Traditional Classroom Instruction in Introductory Agricultural Economics

As many universities are promoting distance courses, the comparative advantages and disadvantages over conventional classroom delivery are being debated. Student attitudes and test performance in an introductory microeconomics course are compared across the two different course delivery formats. Results show that students with average or below-average college aptitude test scores perform more poorly in the distance class.
Multiple levels of the single L-type Ca2+ channel conductance in adult mammalian ventricular myocytes

In cardiac muscle, Ca(2+) entry through the L-type Ca(2+) channel during excitation triggers Ca(2+) release from sarcoplasmic reticulum (SR) via the ryanodine receptor, causing muscle contraction. This Ca(2+) induced Ca(2+) release (CICR) is locally controlled by openings of the single L-type Ca(2+) channel that triggers the opening of ryanodine receptors located within the dyadic junction. The unitary current through the single Ca(2+) channel determines the open probability of the ryanodine receptors, and hence the efficacy of CICR. Here, we report findings of multiple conductance levels of L-type Ca(2+) channels in freshly isolated rat ventricular myocytes. When 10mM Ca(2+) was used in the pipette solution as the charge carrier in the cell-attached configuration, the most frequently occurring conductance levels are 6.9pS and 2.9pS. Three distinct conductance levels were also observed, although infrequently, in the same cell, corresponding to unitary currents of 0.33pA, 0.24pA, and 0.17pA upon depolarization to -10mV. In conclusion, our data demonstrate the existence of multiple single L-type Ca(2+) channel conductance levels in the adult mammalian ventricular myocytes with Ca(2+) as the charge carrier. The multiple conductance levels present heterogeneity in the Ca(2+) trigger signal strength at local dyadic junctions. The physiological significance of this heterogeneity on affecting the efficacy of CICR in the cardiac muscle is discussed.
Randomized versus nondeterministic communication complexity

Our main result is the demonstration of a Boolean function f with nondeterministic and co-nondeterministic complexities O(log n) and e-error randomized complexity O(log2n), for 0 ≤ e
Determination of Unbiased Selectivity Coefficients Using Pulsed Chronopotentiometric Polymeric Membrane Ion Sensors

A new procedure for the determination of selectivity coefficients of neutral carriers using pulsed chronopotentiometric ion selective sensors (pulstrodes) is established. Pulstrode membrane which lacks an ion-exchanger suppresses the zero current ion flux, allowing a Nernstian response slope for even highly discriminated ions. Unlike previously developed methods, unbiased selectivity remains unaltered even with the exposure to the primary ion solution for prolonged time. Studies with potassium-, silver-, and calcium-selective electrodes reveal that pulstrodes yield the same or slightly favorable unbiased selectivity coefficients than reported earlier. In contrast to alternative methods for the determination of unbiased selectivity, this technique offers a unique simplicity and reliability. Therefore the new procedure promises to be a valuable additional tool for the characterization of unbiased selectivity coefficients for the ISEs.
Monoclonal Antibodies for Diagnosis and Treatment

One of the marvels of the host immune response is its response to antigenic foreign substances by manufacturing proteins that bind tenaciously to their targets. These proteins are antibodies or immunoglobulins produced in vast diversity during an individual's lifetime. By virtue of this process, the mammalian host possesses the innate ability to mount an initial response to antigens to which there has been no prior experience and to develop an even more effective response on reexposure to these same substances. This capacity to distinguish self from nonself is one of the most basic aspects of the cellular and humoral arms of the immune response and is one of the primary means by which the host combats infection caused by many different types of pathogens. 1,2 In this context, antibodies have long been recognized as a critical component of host defenses and are capable of binding to invading microbes and microbial toxins. (Arch Surg. 1993;128:1274-1280)
Sodium binding to d-glucuronate residues: Crystal structure of sodium d-glucuronate monohydrate

Abstract Three-dimensional X-ray diffraction data were used to determine the crystal structure of sodium β- d -glucuronate monohydrate, a model system for investigating the factors involved in the binding of sodium ions to d -glucuronate residues of glycosaminoglycans. Crystals of the salt are monoclinic, space group P2 1 , with a = 9.206(3) A, b = 7.007(2) A, c = 7.378(3) A, β = 96.84(3)°, and Z = 2. Intensity data for 858 reflections were measured with an automated diffractometer. A trial structure, obtained by direct methods, was refined by least squares to R = 0.035. An outstanding feature of the crystal packing is the interaction of d -glucuronate anions with sodium ions. The sodium ion is coordinated to three symmetry-related d -glucuronate anions and to one water molecule. The d -glucuronate anion binds sodium cations through the three following sites: one that involves a carboxyl oxygen atom combined with ring oxygen O-5; one that includes a single carboxyl oxygen atom, and one composed of the O-3–O-4 pair of hydroxyl groups.
Recalling Bitterness: Historiography, Memory, and Myth in Maoist China

For Mao Zedong and the Chinese Communist Party, the socialist transformation after 1949 was not only a political and administrative construction, but also a process of transforming the consciousness of the people and rewriting history. To fight lukewarm attitudes and “backward thoughts” among the peasants, as well as their resistance to rural socialist transformation and collectivization of production and their private lives, Mao decided that politicizing the memory of the laboring class and reenacting class struggle would play a significant role in ideological indoctrination and perpetuating revolution. Beginning in the 1950s, the Party made use of grassroots historical writing, oral articulation, and exhibition to tease out the experiences and memories of individuals, families, and communities, with the purpose of legitimizing the rule of the CCP. The cultural movement of recalling the past combined grassroots histories, semi-fictional family sagas, and public oral presentations, as well as political ri...
Patients With Small, Asymptomatic, Unruptured Intracranial Aneurysms and No History of Subarachnoid Hemorrhage Should Be Treated Conservatively

It is foolhardy to remove from consideration of treatment any aneurysm solely because its maximal size is <10 mm or 7 mm. Annually, ≥15 000 American patients have subarachnoid hemorrhage (SAH) from aneurysms with a maximum diameter <7 mm and consequently experience irreparable morbidity and severe mortality. The majority of their aneurysms were, of course, unruptured, single, asymptomatic, and even smaller at some point before rupture. If the rupture rates for <10-mm aneurysms in International Study of Unruptured Intracranial Aneurysm (ISUIA) I1 or <7 mm in ISUIA II2 are used with the known number of ruptured aneurysms of these sizes admitted each year to calculate the prevalence of such small aneurysms in American adults, there is an unbelievably high result: in the range of 7% to 14%. Previous best estimates of prevalence on the basis of retrospective and prospective, radiological and pathological data have been ≈2% for all sizes of aneurysms and for those <10 mm, less than 1%. In autopsy studies, unruptured aneurysms have not outnumbered ruptured ones; the reverse is the case.3 Between ISUIA I1 and ISUIA II,2 the rupture rate …
Radiologic assessment of the paranasal sinuses after endoscopic skull base surgery.

Objectives To identify sinuses demonstrating postoperative radiographic mucosal thickening after endoscopic exposure of the cranial base through the transsphenoidal corridor. Design Retrospective review. Setting University-based medical center. Participants Patients undergoing endoscopic transnasal transsphenoidal approaches to the skull base who had both preoperative and postoperative imaging. Main Outcome Measures Change in preoperative and postoperative imaging scores for each sinus and side at 3 and 6 months. The left-sided undissected sinuses served as internal controls for comparison. Results Fifty-one patients were identified with the aforementioned inclusion and exclusion criteria. The mean difference in preoperative and postoperative imaging scores for the right anterior ethmoid sinus was significantly different from the left-sided equivalents (p = 0.0020). The difference in the frontal sinuses approached significance (p = 0.0625). Conclusions Resection of the lower half of the middle turbinate and maxillary antrostomy and harvest of a nasoseptal flap are associated with an increased radiographic incidence of mucosal thickening of the ipsilateral anterior ethmoids compared with the undissected contralateral side. When accessing the transnasal transsphenoidal corridor for skull base surgery, preservation of native anatomy is associated with a lower incidence of mucosal thickening on postoperative imaging.
Using onsite office hours to connect with healthcare professionals

Four librarians at the A. Alfred Taubman Health Sciences Library recently began offering on-site office hours to four distinct units within the University of Michigan Health System and academic health sciences environment: the School of Dentistry, School of Public Health, Cardiovascular Center, and a research laboratory in the Comprehensive Cancer Center. The goal of each office hour experience was to better reach and more proactively support the information needs of underserved clients, while also providing the librarians with more visibility in the units. Despite relatively low walk-in rates, the librarians found that the exposure gained by offering the office hours made each experience an invariable success.
Full-spectrum FBG analysis of inhomogeneous, fast-varying strain effects

Embedded sensors provide a high sensitivity to sub-surface damage due to their proximity to the damage features. In particular, fiber Bragg gratings (FBG) are easily embedded into laminates with a minimum of perturbation to the surrounding material microstructure. In this paper we summarize some recent advances derived from full-spectral interrogation of FBG sensors for structural health monitoring and damage identification in composites. In particular we present signals from the FBG reflected spectra that have been correlated to the progression of delamination due to multiple low-velocity impacts in woven composite laminates and foam-core sandwich composites. We also discuss recent advances in interrogation systems for these sensors which have permitted dynamic evaluation of these parameters. Finally, spectral distortion can lead to errors in the interpretation of strain values from the peak wavelength measurement when peak waveforms are assumed. We demonstrate that full-spectral interrogation can provide sensor specific error compensation for these measurements.
Molecular approaches to nontoxic antifouling

Summary A consequence of environmental and human health concerns arising from the use of toxic metals in marine antifouling coatings has been to recognise the need for a nontoxic alternative to fouling control. Recent research has focused on two approaches to this problem: the development of (a) foul-release coatings that work on the principle of either low surface free energy or coating ablation, and (b) coatings that incorporate a compound(s) that is nontoxic, or at least environmentally benign, that will deter fouling. Here we discuss the nature of the fouling problem and a new technology that is emerging to address it. The use of natural marine products and of analogues to these compounds holds considerable promise and is an area of intense research. It is recognized, however, that a melding of the technologies of foul-release and foul-deterrence may be required to develop broad spectrum, nontoxic antifouling coatings. This approach may more closely reflect antifouling strategies adopted by marine org...
Two-loop corrections for nuclear matter in a covariant effective field theory

Abstract Although one-loop calculations provide a realistic description of bulk and single-particle nuclear properties, it is necessary to examine loop corrections to develop a systematic finite-density power-counting scheme for the nuclear many-body problem when loops are included. Moreover, it is imperative to study exchange and correlation corrections systematically to make reliable predictions for other nuclear observables. One must also verify that the natural sizes of the one-loop parameters are not destroyed by explicit inclusion of many-body corrections. The loop expansion is applied to a chiral effective hadronic Lagrangian; with the techniques of Infrared Regularization, it is possible to separate out the short-range contributions and to write them as local products of fields that are already present in our Lagrangian. (The appropriate field variables must be re-defined at each order in loops.) The corresponding parameters implicitly include short-range effects to all orders in the interaction, so these effects need not be calculated explicitly. The remaining (long-range) contributions that must be calculated are nonlocal and resemble those in conventional nuclear-structure calculations. Calculations at the two-loop level are carried out to illustrate these techniques at finite densities and to verify that the coupling parameters remain natural when fitted to the empirical properties of equilibrium nuclear matter.
Polymeric metallic electrodes for rechargeable battery applications

A review is presented on the status of plastic metal electrodes, emphasizing the use of polyacetylene as a prototype polymeric material. The electrochemical characteristics of polyacetylene are examined; and the potential use of this material, as well as other types of plastic metal electrodes, in batteries is evaluated. Several problem areas which must be solved before polyacetylene can be widely used in battery applications are discussed, including the problem of electrolyte stability, the problem that the depth of discharge and the energy density is limited by the metal-semiconductor transition, and also the poor electrochemical performance of impure material.
Lead intoxication among demolition workers: the effect of lead on the hepatic cytochrome P-450 system in humans.

Overt clinical disease from undue lead exposure has become a relatively rare phenomenon in adult populations. However, exposure situations that may result in subclinical disease are not uncommon in various occupational settings. Five demolition workers, dismantling an old iron structure covered with lead‐content paint, were studied. The use of cutting torches resulted in lead fumes, with significant exposure, albeit without gross “lead poisoning.” All five workers showed biochemical manifestations of chronic lead intoxication‐that is, elevated blood lead level, inhibition of δ‐aminolevulinic acid dehydratase (ALA‐D), and elevated erythrocytic protoporphyrin concentration (PROTO). The effect of lead on the biosynthesis of heme was assessed by investigating the functional capacity of the cytochrome P‐450 system of the liver, through drug metabolism studies. The plasma elimination rates (half‐lives) of antipyrine and phenylbutazone—drugs primarily metabolized by the hemeprotein P‐450 dependent hepatic micros...
Tools and methodologies to support more sustainable biofuel feedstock production

Increasingly, government regulations, voluntary standards, and company guidelines require that biofuel production complies with sustainability criteria. For some stakeholders, however, compliance with these criteria may seem complex, costly, or unfeasible. What exiting tools, then, might facilitate compliance with a variety of biofuel-related sustainability criteria? This paper presents four existing tools and methodologies that can help stakeholders assess (and mitigate) potential risks associated with feedstock production, and can thus facilitate compliance with requirements under different requirement systems. These include the Integrated Biodiversity Assessment Tool (IBAT), the ARtificial Intelligence for Ecosystem Services (ARIES) tool, the Responsible Cultivation Areas (RCA) methodology, and the related Biofuels + Forest Carbon (Biofuel + FC) methodology.
Time-independent mechanical and physical properties of the ternary 95.5Sn-3.9Ag-0.6Cu solder

The development of a constitutive model for predicting the thermal-mechanical fatigue (TMF) of 95.5Sn-3.9Ag-0.6Cu (wt.%) Pb-free solder interconnects requires the measurement of time-independent mechanical and physical properties. Yield stress was measured over the temperature range of −25–160°C using strain rates of 4.2 × 10−5 s−1 and 8.3 × 10−4 s−1. The yield-stress values ranged from approximately 40 MPa at −25°C to 10 MPa at 160°C for tests performed at 4.2 × 10−5 s−1. The faster strain rate and specimen aging had a limited impact on the yield stress. The true stress/true strain curves indicated that dynamic-recovery and dynamic-recrystallization processes took place in as-cast samples exposed to temperatures of 125°C and 160°C, respectively, while tested at a strain rate of 4.2 × 10−5 s−1. Aging the sample prior to testing, as well as a faster strain rate, mitigated both phenomena. Dynamic Young’s modulus values ranged from 55 GPa at −50°C to 35 GPa at 200°C, while the coefficient of thermal expansion (CTE) increased from approximately 12 × 10−6°C−1 to 24 × 10−6°C−1 for the same temperature range. The aging treatment had little effect on either Young’s modulus or the CTE.