cssi/SciSciGPT-SciSciNet huggingface dataset:
Protein-carbohydrate interaction. VII. Physical and chemical studies on concanavalin A, the hemagglutinin of the jack bean.

Abstract Concanavalin A yielded a monodiperse pattern in the analytical ultracentrifuge in the pH range 2–5. The sedimentation coefficient, s o 20, w in pH 5 acetate buffer containing 0.1 m NaCl (total Γ 2 = 0.20 ) was 4S. At pH 7 and above, a two-peak schlieren pattern was observed, the faster component (about 7S) probably representing a dimer. On the basis of an s 20, w of 3.9S; a D 20, w of 5.43 × 10−7 cm 2 /second, and a ī V of 0.73 ml/gm, a molecular weight of 68,000 was calculated (0.10 m acetate, NaCl, Γr 2 = 0.45 ) for the homogeneous component at pH 5. From free-boundary electrophoresis data the isoelectric point of Concanavalin A was determined to be 7.1 ± 0.1. Starch gel electrophoresis patterns of concanavalin A in borate buffer (pH 8.6) were characterized by an anodically migrating streak. Incorporation of d -glucose into the gel gave a single sharp band which migrated slowly toward the cathode, the glucose probably inhibiting protein-starch interaction. Gel filtration experiments with Biogel P-100 suggested that at pH 5 the molecular weight of Concanavalin A is in the vicinity of 50,000; at pH 7.5 concanavalin A is completely excluded, an indication that a high molecular weight species probably is formed by the association of subunits. Concanavalin A has an extinction coefficient, E 1% 1 cm of 11.4 ± 0.1, the molar ratio Mtyrosine/ Mtryptophan being 1.78. Unlike other phytohemagglutinins, concanavalin A does not contain cysteine (or cystine) or carbohydrate. Aspartic acid and serine constitute the most abundant residues, and the protein has a high amide content (68.6 groups/10 5 gm protein). Amino terminal studies showed the presence of 1.5 moles DNP-alanine/ 68,000 gm protein together with very small amounts of DNP-serine and DNP-glycine. The manganese content of concanavalin A was found to be 0.029 and 0.036%, by activation analysis and emission spectroscopy, respectively.
Chapter 15 Future directions: Satellite observations of tropospheric chemistry

Publisher Summary This chapter focuses on future directions in the satellite observations of tropospheric chemistry. The troposphere is an essential component of the earth's life support system and is the gateway for the exchange of chemicals among different geochemical reservoirs of the earth. Satellite observation of tropospheric composition is considerably more difficult than for the stratosphere because of the complexities involved in accounting for effects due to clouds, aerosols, water vapor, and the ozone layer overhead. To date, tropospheric chemistry observations from space are limited to a few weeks of carbon monoxide (CO) measurements from the Measurement of Atmospheric Pollution from Satellites (MAPS) instrument aboard the space shuttle, indirect inferences of tropical ozone from satellite measurements of the total ozone column, and preliminary data sets for the column content of a few species (O3, NO2, HCHO, SO2, and BrO) from the Global Ozone Monitoring Experiment (GOME) solar backscatter instrument launched in 1995. It is expected that within the next few years, many studies will be performed to investigate the export of air pollution from major regions around the world. Satellite sensors will clearly be the platform of choice for such studies. These will allow the first detailed testing of global models of tropospheric chemistry.
On financial contracting: An analysis of bond covenants

Abstract With risky debt outstanding, stockholder actions aimed at maximizing the value of their equity claim can result in a reduction in the value of both the firm and its outstanding bonds. We examine ways in which debt contracts are written to control the conflict between bondholders and stockholders. We find that extensive direct restrictions on production/investment policy would be expensive to employ and are not observed. However, dividend and financing policy restrictions are written to give stockholders incentives to follow a firm-value-maximizing production/investment policy. Taking into account how contracts control the bondholder- stockholder conflict leads to a number of testable propositions about the specific form of the debt contract that a firm will choose.
Effects of nitric oxide on stem cell therapy

The use of stem cells as a research tool and a therapeutic vehicle has demonstrated their great potential in the treatment of various diseases. With unveiling of nitric oxide synthase (NOS) universally present at various levels in nearly all types of body tissues, the potential therapeutic implication of nitric oxide (NO) has been magnified, and thus scientists have explored new treatment strategies involved with stem cells and NO against various diseases. As the functionality of NO encompasses cardiovascular, neuronal and immune systems, NO is involved in stem cell differentiation, epigenetic regulation and immune suppression. Stem cells trigger cellular responses to external signals on the basis of both NO specific pathways and concerted action with endogenous compounds including stem cell regulators. As potency and interaction of NO with stem cells generally depend on the concentrations of NO and the presence of the cofactors at the active site, the suitable carriers for NO delivery is integral for exerting maximal efficacy of stem cells. The innovative utilization of NO functionality and involved mechanisms would invariably alter the paradigm of therapeutic application of stem cells. Future prospects in NO-involved stem cell research which promises to enhance drug discovery efforts by opening new era to improve drug efficacy, reduce drug toxicity and understand disease mechanisms and pathways, were also addressed.
Design of a programmable OTA with multi-decade transconductance adjustment

A programmable operational transconductance amplifier (OTA) structure is presented which permits a g/sub m/ adjustment by greater than two decades without severe degradation in linearity. This is achieved by including a programmable current mirror structure in the OTA output stage for coarse g/sub m/ adjustment in addition to a fine g/sub m/ adjustment via control of a bias current in the OTA differential input stage. Experimental results indicate that less than 1% nonlinearity in the transconductance characteristic is achieved throughout the g/sub m/ adjustment range for input signals less than 1$iV/sub pp/. >
Slow and Fast Responses in Cockroach Leg Muscle

1. Intracellular recording from individual muscle fibres of the flexor tibiae of the cockroach shows two types of action potentials. One of these represents fast fibre activity, while the other represents slow fibre activity in this muscle. 2. The fast response consists of an all-or-none potential varying from 40 to 85 mV., with 6o% of the responses between 55 and 70 mV. This potential has an overshoot over the resting potential, and is followed by an absolute and a relative refractory period. For these reasons it is considered likely that the potential is a propagated one. The slow response is a small, facilitating potential, varying from 8 to 20 mV., and is quite likely a local phenomenon. 3. All the evidence indicates that the two types of activity do not take place in the same muscle fibres, but rather represent the responses of two different types of fibres, as is the case in some amphibian muscles. 4. Gradation of activity in the fast system seems to depend solely on the activation of a very small number of motor units and on mechanical summation. The response of this system shows little, if any, facilitation as the frequency of stimulation is increased. The facilitating slow system may be concerned with slower, more finely graded movements. 5. The resting potential in roach muscle has an amplitude of 45 ±9 mV., which falls within the range expected on the basis of the intracellular and extracellular potassium concentrations. 6. Slow and fast fibre activity in insects and Crustacea is discussed, and a revision of the earlier work on Crustacea with the use of intracellular recording is suggested.
Tumor Angiogenesis as a Target for Dietary Cancer Prevention

Between 2000 and 2050, the number of new cancer patients diagnosed annually is expected to double, with an accompanying increase in treatment costs of more than $80 billion over just the next decade. Efficacious strategies for cancer prevention will therefore be vital for improving patients' quality of life and reducing healthcare costs. Judah Folkman first proposed antiangiogenesis as a strategy for preventing dormant microtumors from progressing to invasive cancer. Although antiangiogenic drugs are now available for many advanced malignancies (colorectal, lung, breast, kidney, liver, brain, thyroid, neuroendocrine, multiple myeloma, myelodysplastic syndrome), cost and toxicity considerations preclude their broad use for cancer prevention. Potent antiangiogenic molecules have now been identified in dietary sources, suggesting that a rationally designed antiangiogenic diet could provide a safe, widely available, and novel strategy for preventing cancer. This paper presents the scientific, epidemiologic, and clinical evidence supporting the role of an antiangiogenic diet for cancer prevention.
Extinction of ethanol-induced conditioned place preference and conditioned place aversion: effects of naloxone

Four experiments examined the effect of naloxone pretreatment on the expression and extinction of ethanol-induced conditioned place preference (experiments 1, 2, 4) or conditioned place aversion (experiments 1, 3). DBA/2 J mice received four pairings of a distinctive tactile (floor) stimulus (CS) with injection of ethanol (2 g/kg) given either immediately before or after 5-min exposure to the CS. A different stimulus was paired with injection of saline. Pre-CS injection of ethanol produced conditioned place preference, whereas post-CS injection of ethanol produced conditioned place aversion. Both behaviors extinguished partially during repeated choice testing after vehicle injection. Naloxone (10 mg/kg) had little effect on the initial expression of conditioned place preference, but facilitated its extinction. Moreover, repeated naloxone testing resulted in the expression of a weak conditioned place aversion to the CS that initially elicited a place preference. In contrast, naloxone (1.5 or 10 mg/kg) enhanced expression of conditioned place aversion, thereby increasing its resistance to extinction. A control experiment (experiment 4) indicated that repeated testing with a different aversive drug, lithium chloride, did not affect rate of extinction or produce an aversion to the CS previously paired with ethanol. These findings do not support the suggestion that naloxone facilitates the general processes that underlie extinction of associative learning. Also, these data are not readily explained by the conditioning of place aversion at the time of testing. Rather, naloxone’s effects appear to reflect a selective influence on maintenance of ethanol’s conditioned rewarding effect, an effect that may be mediated by release of endogenous opioids. Overall, these findings encourage further consideration of the use of opiate antagonists in the treatment of alcoholism.
Traffic Counts, Symbols & Agendas: A Critique of the Campaign Against Trafficking of Human Beings:

Today's international campaign against the trafficking of women for sexual exploitation is examined from a critical and a historical perspective. Descriptions of the nature and magnitude of the problem are questioned, as is the accuracy of the campaign's central image of the nice girl forced into sexual exploitation. Available data suggest that the campaign is a long way from meeting its instrumental goals of preventing trafficking, prosecuting traffickers or protecting victims. However, today's phase of the campaign has had important symbolic successes, winning broad political support; providing leverage for feminists to push for improving the status of women and promoting conventional morality with its anti-prostitution orientation as the globally accepted norm. The conflicts among the moral entrepreneurs that have driven the campaign are described. The campaign's continued viability is said to rest upon whether its central image can be sustained, something that has become problematic as the result of t...
Functional Group Contributions to Partial Molar Compressibilities of Alcohols in Water

A recently developed methodology for evaluating solute functional group contributions to the partial molar compressibility of solution [Lockwood, D. M.; Rossky, P. J. J. Phys. Chem. B. 1999, 103, 1982] is used to examine solvation of methanol and ethanol in water. Additive contributions to the compressibility are resolved for the methyl and hydroxyl groups of each solute, and the results are shown to be the same for both solutes within statistical error. Further, the effect of each functional group on the solvent is found to be localized in the vicinity of that functional group, explaining the apparent independence of functional group contributions observed experimentally by other workers. The difference in partial molar compressibility between methanol and ethanol can be attributed to localized solvent perturbation by the methylene group in ethanol. For the potential functions employed, compressibilities calculated via classical molecular dynamics simulations are in best agreement with experiments perfor...
Hormonal measurement in rat anterior pituitary cell cultures: Loss of immunoreactive LH counteracted by fetal calf serum and bacitracin

Abstract Immunoassayable LH in media samples from rat anterior pituitary cell cultures declines during storage and only 20% of the LH remains after 4 weeks at -20°C. The LH loss was not due to bacterial contamination or to damage to the hormone from repeated freezing and thawing. SDS-PAGE of 125IrLH in media samples showed greater recovery of 125IrLH when 1 mM bacitracin or 2% fetal calf serum were present in the medium. The ratio of intact: subunit 125IrLH was unchanged by the presence of bacitracin or fetal calf serum indicating that the loss of immunoreactive LH was not due to dissociation of intact hormone. LH appears to be irreversibly altered in stored culture media, a process which can be prevented by the addition of bacitracin or fetal calf serum to the media prior to storage. The use of either substance allows accurate and reproducible measurement of LH released from pituitary cells in culture.
Stimulated Radiative Association of Li and H in the Early Universe

The enhancement of the rate coefficient for the radiative association of Li and H to form LiH arising from stimulated emission by the cosmic background radiation field is calculated. It is shown that the effect on the fractional abundance of LiH in the early universe for redshifts z between 1000 and 10 is small.
Some comments on the projectibility of anthropological hypotheses: Samoa briefly revisited

The purpose of this article is to examine the applicability of the theory of projection for Anthropological hypotheses. The claim is made that Goodman's classic statement of the problem does not apply in its entirety to actual Anthropological hypotheses. The recent Freeman-Mead debate is employed as a framework for the discussion, illustrating that the issue of projectibility, while central for the social sciences, is best used as a “backdrop” to illustrate several important methodological problems. For Anthropology, and other related social sciences, the central methodological problem, which is directly related to the projectibility one, is the development and justification of evidence-rules that can be used for a theory of confirmation. A preliminary attempt is then made to articulate the nature of these rules within the general Hempelian framework of qualitative confirmation.
Induction of Anemia in Female G57B1/6 Mice with Emulsions of Complete Freund's Adjuvant and Erythrocytes

SummaryAn experimental model of anemia (decrease in venous hematocrit) in association with chronic inflammation has been described. It was readily induced in adult female C57B1/6 mice by the intraperitoneal injection of 25% allogeneic C3H or syngeneic C57B1/6 erythrocytes emulsified in complete Freund's adjuvant. Direct Coombs tests were negative but hemolysis was a significant factor. Increased plasma volume appeared to be a second important component. Splenomegaly, peritoneal inflammation and fibrosis, hyperplasia of the reticuloendothelial system, plasmocytosis, and miliary hepatic granulomata occurred when the adjuvant was intraperitoneally injected. The intensity of these reactions bore a close relationship to the anemia. Splenectomy prevented hemolysis and modified the anemia but it did not totally abolish the events producing the increased plasma volume and decreased venous hematocrit.
Suppression of tumorigenicity in neuroblastoma cells by upregulation of human vasoactive intestinal peptide receptor type 1

Abstract We hypothesize that vasoactive intestinal peptide (VIP) promotes neural crest differentiation through VIP receptor type I (VPAC1). In order to test this hypothesis, SKNSH neuroblastoma cells were stably transfected with VPAC1 and receptor expression was verified by real-time RT-PCR. Overexpression of VPAC1 in SKNSH cells resulted in upregulation of endogenous retinoic acid receptor expression for both RARα and RXRα with no change in expression of RARβ. Transfected cells demonstrated high affinity binding of VIP (KD=0.2 nM) and VIP-mediated stimulation of adenylate cyclase and a shift in cell cycle kinetics to a near triploid DNA index in G1. SKNSH/VPAC1 cells treated with VIP were observed to express a more differentiated phenotype compared to wild type cells as characterized by an increase in tissue transglutaminase II and a decrease in bcl-2 immunostaining. VIP-induced differentiation effects were potentiated by retinoic acid. This differentiation resulted in decreased proliferative potential in a xenograft model. Whereas, wild type SKNSH cells induced tumor growth in 100% of nude mice within 13 days post-injection, SKNSH transfected with VPAC1 demonstrated no tumor formation in xenografts followed for 6 months. Taken together, these data support the hypothesis that VIP modulation of neural crest differentiation is mediated via VPAC1 and that high expression of VPAC1 induces differentiation in and decreases tumorigenicity of neuroblastoma cells.
Autothermal reforming of aliphatic and aromatic hydrocarbon liquids

Results are presented from a study of the autothermal reforming of paraffins and aromatics over nickel catalysts. The trials were performed to examine the carbon products that appear when steam is passed over hydrocarbon liquids to form H2-rich gases, i.e., the autothermal process (ATR). Attention was given to n-hexane, n-tetradecane, benzene, and benzene solutions of naphthalene with reactant preheat to 1000-1150 F. The carbon-formation limit was sought as a function of the steam-to-carbon and oxygen to carbon molar ratios at constant pressure and the preheat temperatures. The catalyst bed was examined after each trial to identify the locations and types of carbon formed using SEM, thermal gravimetric analysis, and X ray diffraction techniques. The hydrocarbon fuels each had a separate temperature and reaction profile, as well as carbon formation characteristics. No carbon formation was observed in the upper layer of the reactor bed, while both gas phase and surface-grown deposits were present in the lower part. The results are concluded of use in the study of No. 2 fuel oil for ATR feedstock.
Early Low-Titer Neutralizing Antibodies Impede HIV-1 Replication and Select for Virus Escape

Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab) responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1∶20 to 1∶50 (IC50) selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env) in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1–V3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical infection is typically one.
Preferred Route for vic-Dichloride Formation from Alkenes. Comparison of Cyclohexene Chlorination with Chlorine, Sulfuryl Chloride, and Trichloramine

Abstract The objective of this study was to determine the best method for generating vic-dichlorides from alkenes with chlorine, trichloramine, and sulfuryl choride as candidate chlorinating agents. In general, cyclohexene was employed as the model alkene.
The Hotspot Matrix: A Framework for the Spatio‐Temporal Targeting of Crime Reduction

The growth of intelligence‐led policing has placed even greater emphasis on the clear identification of crime hotspots as well as the choice of the crime reduction or detection strategy identified to combat a problem. Crime hotspots are becoming central to policing strategy in many locations, as they enable an operational commander to focus resources into the areas of highest need. This paper outlines the techniques used to identify the spatial and temporal components of crime hotspots, and utilizes these methods to identify three broad categories of temporal hotspot and three broad categories of spatial hotspot. These categories are described in the form of a Hotspot Matrix. Real examples show how the spatial and temporal characteristics combine within the hotspot matrix, and the paper concludes by showing how operational commanders and crime prevention practitioners might employ the hotspot matrix to determine an appropriate prevention or detection strategy.
Vesicle biomechanics in a time-varying magnetic field.

Background Cells exhibit distortion when exposed to a strong electric field, suggesting that the field imposes control over cellular biomechanics. Closed pure lipid bilayer membranes (vesicles) have been widely used for the experimental and theoretical studies of cellular biomechanics under this electrodeformation. An alternative method used to generate an electric field is by electromagnetic induction with a time-varying magnetic field. References reporting the magnetic control of cellular mechanics have recently emerged. However, theoretical analysis of the cellular mechanics under a time-varying magnetic field is inadequate. We developed an analytical theory to investigate the biomechanics of a modeled vesicle under a time-varying magnetic field. Following previous publications and to simplify the calculation, this model treated the inner and suspending media as lossy dielectrics, the membrane thickness set at zero, and the electric resistance of the membrane assumed to be negligible. This work provided the first analytical solutions for the surface charges, electric field, radial pressure, overall translational forces, and rotational torques introduced on a vesicle by the time-varying magnetic field. Frequency responses of these measures were analyzed, particularly the frequency used clinically by transcranial magnetic stimulation (TMS).
Partial isolation and characterization of the 15-hydroxyprostaglandin dehydrogenases and 9-ketoprostaglandin reductases in rabbit kidney

Abstract Three types of 15-hydroxyprostaglandin dehydrogenase were identified in rabbit whole kidney homogenate when the centrifuged homogenate was sequentially fractionated by ammonium sulfate precipitation, DEAE-cellulose and Mātrex Gel Blue A chromatographies, and Sephadex gel filtration. The first type is not adsorbed to DEAE-cellulose (peak 1). It catalyzes oxidoreduction of prostaglandins at both the C-15 and C-9 positions, is more active with NADP than NAD, is inhibited by indomethacin and ethacrynic acid, and migrates as three bands on disc gel electrophoresis. The second type is adsorbed to DEAE-cellulose (peak 2). It also migrates as multiple electrophoretic bands, has similar catalytic actions and co-factor requirements as the peak 1 enzyme and is inhibited by indomethacin and ethacrynic acid. A third type of 15-hydroxyprostaglandin dehydrogenase is also adsorbed to DEAE-cellulose but is partially separable from the other peak 2 enzymes on Mātrex Gel Blue A and differs from those enzymes in preferentially oxidizing PGI 2 . It migrates as a single electrophoretic band and is also inhibited by indomethacin and ethacrynic acid.
Factors predicting the persistence of asthma insights from the Tucson children's respiratory study

Abstract The Tucson Children’s Respiratory Study (TCRS) is a longitudinal, epidemiology study of respiratory health, which enrolled a birth cohort of over 1200 children from 1980 to 1984. Over 800 of these children were still being followed at adolescence allowing the characterization of several distinct wheezing phenotypes throughout childhood, as well as, those risk factors associated with the development of asthma and its persistence. Evaluating the persistence of asthma is a complex issue. There are several distinct wheezing phenotypes in childhood, which vary in prevalence and course with age. The challenge here is that the phenotypes of wheezing illness change with age; i.e. in infancy most children with wheezing illnesses are transient wheezers who will cease wheezing by age six. In contrast, by age six most children with wheeze have either persisted since infancy without apparent remission or have late onset wheeze. Both of these groups have increased rates of atopy representing dysregulated immune systems. Although its prevalence decreases substantively by early adolescence, non-atopic wheeze continues in a relevant proportion of school age children. Further, although the majority of adolescents with asthma have developed wheeze by age six, there are some who first present with asthma after this age. Thus, as children age, the meaning of wheezing transitions from most likely not being asthma in the first 3 years to most likely being asthma by late adolescence. This article will review the progression of wheezing from infancy through early adolescence and will address both changes in phenotypes as well as risk factors for both persistent and incident asthma in childhood.
Surgical techniques: robot-assisted laparoscopic colposacropexy with the da Vinci(®) surgical system.

Colposacropexy is the gold-standard operation for repair of apical vaginal support defects. While it is feasible to perform this operation using conventional laparoscopic techniques, a limited number of surgeons have mastered the advanced minimally invasive skills that are required. Introduction of the da Vinci® robotic system with instruments that have improved dexterity and precision and a camera system with three-dimensional imaging presents an opportunity for more surgeons treating women with pelvic organ prolapse to perform the procedure laparoscopically. This paper will outline a technique that is exactly modeled after the open procedure for completion of a robotic-assisted colposacropexy using the da Vinci® surgical system.
Hope in the Social Environment: Factors Affecting Future Aspirations and School Self-Efficacy for Youth in Urban Environments

Having a sense of hope and aspirations for the future are often conceptualized as components of resilience for youth in urban environments. However, less is known about the factors that may influence how young people develop their future aspirations, and how those aspirations may impact their experiences at school. This study uses structural equation modeling to identify some potential pathways through which parental relationships and neighborhood environments may impact perceptions of future success and associations between future aspirations and self-efficacy in school settings for adolescents in urban environments. Data from a self-efficacy questionnaire completed by 489 participants in the Project on Human Development in Chicago Neighborhoods (mean age 17.2) were used to test the fit of our conceptual model. The analyses indicated strong relationships among the variables and a robust model fit, as assessed by multiple fit indices. The findings suggest that several factors, including neighborhood safety and supportive parental relationships, can help youth maintain hope for the future and that such future aspirations can bolster adolescents’ sense of self-efficacy in school. Implications of these findings for social work theory, practice, policy, and research are described.
A Note on the Use of Bootstrap Tetrad Tests for Covariance Structures

Abstract Tetrad tests are a valuable tool for testing covariance structures, particularly when other tests such as the likelihood ratio test are not appropriate. However the implementation of tetrad tests is complicated by the fact that there are often multiple sets of nonredundant vanishing tetrads, and also by computational limitations, particularly for bootstrap tetrad tests for models with a large number of indicator variables. We show that a simple modification of a bootstrap tetrad test can overcome these limitations. Another beneficial result of this modification is that it can increase the power of the test.
Double inclusion of ferrocene within a doubly interpenetrated three-dimensional framework based on a resorcin[4]arene

Abstract Co-crystallization of C-methylcalix[4]resorcinarene (1) and 4,4′-bipyridine (2) from ethanol in the presence of ferrocene affords single crystals of 3h·2.15 (ethanol)·0.85 (ferrocene) that consist of a doubly interpenetrated 3D hydrogen-bonded framework, 1·1.5(2) (3h). The 3D framework 3h is a supramolecular isomer of a reported 2D framework 3g and possesses box-shaped cavities that include two molecules of ferrocene as a guest.
Multiple cycles of high dose chemotherapy supported by hematopoietic progenitor cells as treatment for patients with advanced malignancies

BACKGROUND Retrospective studies suggest that dose intensity is an important determinant of outcome in the treatment of patients with a variety of malignant diseases such as breast cancer, ovarian cancer, and lymphoma. Unfortunately, these results have not been clearly substantiated in prospective randomized trials. One problem with these studies may be that the degree of dose escalation is not sufficient to result in an improved outcome because the chemotherapy doses are limited by hematopoietic toxicity. In an attempt to deliver more dose-intensive therapy, the feasibility of the administration of multiple cycles of high dose chemotherapy with hematopoietic progenitor cell and growth factor support was investigated in patients with advanced malignancies. METHODS Nineteen patients with metastatic breast cancer and six patients with refractory non-Hodgkin's lymphoma were initially treated with etoposide (VP-16) (2 gm/m2) and granulocyte-colony stimulating factor (G-CSF). Peripheral blood hematopoietic progenitor cells were collected by leukapheresis and cryopreserved as the patients' leukocyte counts recovered from the nadir induced by VP-16. Patients were then treated with four cycles of mitoxantrone (18 mg/m2), thiotepa (150-200 mg/m2) and cyclophosphamide (4500-5000 mg/m2) as a 48-72 hour continuous infusion followed by infusion of one-quarter of their progenitor cells 48 hours later. All patients also received G-CSF (5 micrograms/kg/day) until engraftment. RESULTS A total of 88 of a planned 100 cycles of therapy were administered to these 25 patients. The median time to recovery of an absolute neutrophil count of 500/microliters or greater was 13-14 days (range, 7-18 days) and time to recovery of a platelet count of 20,000/microliters or greater was 13-14 days (range, 7-16 days) after the initiation of each cycle of chemotherapy. The median number of platelet transfusions required after each cycle was 2-3 (range, 0-18 transfusions) and the number of erythrocyte transfusions was 4 (range, 0-10). The most common toxicity was diarrhea. Prophylactic intravenous antibiotics were administered to avoid fever with neutropenia. Two patients developed interstitial pneumonitis and one patient died. One heavily pretreated patient failed to engraft after the first cycle. Reversible veno-occlusive disease of the liver developed in one patient after the fourth cycle of therapy. Four patients progressed while on therapy. Eight patients were disease free and 13 patients had a partial response or had a positive bone scan as the only evidence of disease at the completion of therapy. Seven patients, two with lymphoma and five with breast cancer (28%), remain progression free with a median follow-up of 24.7 months (range, 17-28 months). CONCLUSIONS Support with hematopoietic progenitor cells and growth factors allows the timely administration of repetitive cycles of high dose chemotherapy, resulting in a significant increase in dose intensity with acceptable toxicity.
Postcolonialism, language, and the visual: By way of Haiti

Who can claim the condition of postcoloniality and how can it be represented today? What is the role of cinema in disseminating knowledge about the “periphery”? This paper will argue that when a film privileges linguistic diversity, it can communicate better than the written word the full texture of minor or resistant identities. My example is taken from a series of short stories by Dany Laferriere that deal with sexual or “romance tourism” in Haiti, and that form the basis of French cineaste Laurent Cantet’s Vers le sud. Much more than a film “adaptation” of the written text, Cantet’s film is a statement about Haiti, poverty, political tyranny, and “work” as alienated labor (a recurrent theme of all his films). What are the interpretive and critical issues that arise from the circulation of words and images in a global cultural market that can exacerbate the traffic in desire between North and South, as well as between writers, filmmakers, and their audiences? Is Cantet a “postcolonial” filmmaker, and, i...
Vegetation diversity and insect pest outbreaks

The development of most insect pest complexes have been associated with the expansion of crop monocultures at the expense of weeds, hedgerows and other natural vegetation, thereby decreasing local habitat diversity. This simplification can seriously affect the abundance and efficiency of natural enemies, which depend on habitat complexity for sources of alternate prey/hosts, pollen and nectar, shelter, nesting and overwintering sites. Plant diversification of agroecosystems can result in increased environmental opportunities for natural enemies, and consequently improved biological pest control. Agronomically, there are two ways to design plant diverse cropping systems. One way is by manipulating the vegetation of field margins, and this can imply the management of the species composition and density of plants in ditchbanks, hedgerows, windbreaks and other types of shelterbelts. Within‐field plant diversity can be manipulated by designing polycultures of various temporal and spatial crop arrangements. The...
Quantum Coherence in a One-Electron Semiconductor Charge Qubit

We study quantum coherence in a semiconductor charge qubit formed from a GaAs double quantum dot containing a single electron. Voltage pulses are applied to depletion gates to drive qubit rotations and noninvasive state readout is achieved using a quantum point contact charge detector. We measure a maximum coherence time of ∼7 ns at the charge degeneracy point, where the qubit level splitting is first-order insensitive to gate voltage fluctuations. We compare measurements of the coherence time as a function of detuning with numerical simulations and predictions from a 1/f noise model.
Gamma Irradiation: Effects on Biomechanical Properties of Human Bone-Patellar Tendon-Bone Allografts

Sixty 10-mm bone-patellar tendon-bone allografts from young human donors were placed into four test groups, a control fresh-frozen group and three fresh-frozen irradiated groups. The irradiated groups were exposed to 2.0, 3.0, or 4.0 Mrad of gamma irradiation. The specimens were tested to tensile failure. The initial biomechanical strength of fresh-frozen allografts was reduced up to 15% when compared with fresh-frozen controls after 2.0 Mrad of irradiation. Maximum force, strain energy, modulus, and maximum stress demonstrated a statistically significant reduction after 2.0 Mrad of irradiation (P < 0.01). Stiffness, elongation, and strain were reduced but not with statistical significance. A 10% to 24% and 19% to 46% reduction in all biomechanical properties were found after 3.0 (P < 0.005) and 4.0 (P < 0.0005) Mrad of irradiation, respectively. After irradiation with a 4.0 Mrad dose, the ultimate load was below that of reported values for the human anterior cruciate ligament. It is clinically important to observe and document changes in human ligaments that result from currently used doses of gamma irradiation. The results from this study provide important information regarding the initial biomechanical properties of fresh-frozen human bone-patellar tendon-bone allografts after bacterial sterilization with gamma irradiation. The current accepted dose for sterilization is between 1.5 and 2.5 Mrad. There appeared to be a dose-dependent effect of irradiation on all the biomechanical parameters studied. Four of seven parameters were found to be reduced after 2.0 Mrad of irradiation. Reductions were found in all parameters after 3.0 and 4.0 Mrad of irradiation.
Characterizing daily movements, nomadic movements, and reproductive migrations of Panulirus argus around the Western Sambo Ecological Reserve (Florida, USA) using acoustic telemetry

Abstract The movements of the Caribbean spiny lobster (Panulirus argus) were studied in three subregions: (1) patch reefs, (2) forereef, and (3) outlier reef, in and around the Western Sambo Ecological Reserve (WSER) (Florida, USA) using acoustic tags and receivers. The studies took place from the June 2003 through July 2007 and involved various receiver deployments such as tracking grids and emigration rings designed to track relatively short daily movements and long-distance (>1 km) movements. Daily movements were found to be highly repetitive in some individual lobsters in both the patch reef and the forereef. Some forereef lobsters shifted foraging preference between the forereef itself (63%), a shallow back reef area (10%), reef base (9%), and a deeper reef base area (4%), with undetermined making up the remainder. Approximately one-third of the patch reef resident lobsters exhibited significantly enhanced nocturnal movements during periods of low or no lunar illumination. Twenty-two nomadic movements were detected and occurred throughout the year and included individuals that moved between Western Sambo Ecological Reserve and the outlier reef south of the reserve. Lateral movements detected along the forereef were exhibited by only a few male lobsters. Reproductive migrations by reproductively active female lobsters were observed in all subregions. These movements are characterized by a sudden rapid southward move initiated near midnight. For patch reef and forereef females, the destination is deep water to the south of the forereef. Outlier reef females moved to deeper water to their south. Up to three reproductive migrations were conducted at a median interval of 25 days (16 multiple trips detected). With respect to one of WSER's stated management goals, i.e., to protect life histories, lobster movements have shown that the outlier reef subregion, located 1 km south of the southern WSER border, is integral to the spiny lobster life history and should be considered for inclusion into WSER.
Endogenous Substrates of Sphingosine-Dependent Kinases (SDKs) Are Chaperone Proteins: Heat Shock Proteins, Glucose-Regulated Proteins, Protein Disulfide Isomerase, and Calreticulin†

Protein kinases whose activity is detectable only in the presence of sphingosine (Sph) or N,N'-dimethyl-Sph (DMS), but not in the presence of 15 other sphingolipids, phospholipids, and glycerolipids tested (Megidish, T., et al. (1995) Biochem. Biophys. Res. Commun. 216, 739-747), have been termed "sphingosine-dependent kinases" (SDKs). We showed previously that a purified SDK (termed "SDK1") phosphorylates a specific Ser position of adapter/chaperone protein 14-3-3 isoforms beta, eta, and zeta but not tau or sigma (Megidish, T., et al. (1998) J. Biol. Chem. 273, 21834-45). In this study we found the following: (i) other SDKs with different substrate specificities are present in cytosolic and membrane extracts of mouse Balb/c 3T3 (A31) fibroblasts. (ii) The activation of these SDKs is specific to D-erythro-Sph and its N-methyl derivatives, the effect of L-threo-Sph or its N-methyl derivatives is minimal, and nonspecific cationic amphiphiles have no effect at all. An SDK separated as fractions "TN31-33" phosphorylated a 50 kDa substrate which was identified as calreticulin, as well as two endogenous substrates with molecular mass 58 and 55 kDa, both identified as protein disulfide isomerase (PDI). This SDK, which specifically phosphorylates calreticulin and PDI, both molecular chaperones found at high levels in endoplasmic reticulum, is tentatively termed "SDK2". Another SDK activity was copurified with glucose-regulated protein (GRP) and heat shock proteins (HSP). One GRP substrate had the same amino acid sequence as GRP94 (synonym: endoplasmin); another HSP substrate had the same amino acid sequence as mouse HSP86 or HSP84, the analogues of human HSP90. An SDK activity separated and present in "fraction 42" from Q-Sepharose chromatography specifically phosphorylated GRP105 (or GRP94) and HSP68 but did not phosphorylate PDI or 14-3-3. This SDK is clearly different from other SDKs in its substrate specificity and is tentatively termed "SDK3". Interestingly, substrates of all these SDKs so far identified are molecular chaperones or adapters capable of binding to enzymes and key molecules involved in signal transduction, maintaining tertiary structure of bioactive molecules, or maintaining cellular homeostasis in response to environmental stress. Thus, the essential role of Sph and DMS is to activate molecular chaperones, thereby providing a link to the mechanism by which SDK activity regulates cellular homeostasis and signal transduction.
Influence of Antibiotics Administered in Therapeutic Doses on Colonisation Resistance Against Enteric Pathogens in Mice

Colonisation resistance against oral challenge with Salmonella typhimurium, Shigella flexneri and enterotoxigenic Escherichia coli (ETEC) was determined using untreated mice and mice pre-treated with therapeutic doses of either amoxicillin, chloramphenicol, erythromycin, penicillin or trimethoprim-sulfamethoxazole (TMS), or with streptomycin, administered in high dose. The effects of these antibiotics on the pH levels and volatile fatty acid (VFA) concentrations of caecal contents were also determined. Only streptomycin treatment altered colonisation resistance. The incidence of caecal colonisation by all three pathogens and their populations were significantly greater in streptomycin treated than untreated mice. Except for an increase in the incidence of colonisation by ETEC after erythromycin treatment, none of the antibiotics, administered in therapeutic doses, produced significant effects on colonisation resistance. Relative to untreated mice, streptomycin treatment caused a statistically significant decrease in total caecal VFA's, from 60.80 μeq/g to 21.63 μeq/g, and a significant increase in pH from 6.75 to 7.04. Treatment with TMS caused an increase in total caecal VFA to 91.18 μeq/g. Treatment with the other antibiotics failed to produce significant changes in total caecal VFA's and, with the exception of chloramphenicol treatment resulting in a pH of 7, in caecal pH levels. All of the pathogens were sensitive to the presence of VFA in nutrient broth. In every case, their populations, after 12 h incubation, were greatest in broth containing 21.63 μeq/ml VFA adjusted to pH 7.04, simulating conditions in the caecum of streptomycin treated mice, and were smallest in broth containing 91.18 μeq/ml VFA adjusted to pH 6.74, simulating conditions in the caecum of TMS treated mice. Despite the suppressive effects of conditions simulating TMS treatment in vitro , mice treated with this combination of antibiotics were no more resistant to colonisation with the pathogens than were untreated mice. The results demonstrate that antibiotics, administered in therapeutic doses, have little effect on colonisation resistance against enteric pathogens in mice and suggest that a similar situation may exist in humans. Keywords: Antibiotics; Colonisation resistance; Mice.
An ocean model's response to north Atlantic Oscillation-like wind forcing

The response of the Atlantic Ocean to North Atlantic Oscillation (NAO)-like wind forcing was investigated using an ocean-only general circulation model coupled to an atmospheric boundary layer model. A series of idealized experiments was performed to investigate the interannual to multi-decadal frequency response of the ocean to a winter wind anomaly pattern. Overall, the strength of the SST response increased slightly with longer forcing periods. In the subpolar gyre, however, the model showed a broad response maximum in the decadal band (12-16 years).
Propagation of polarized light beams through biological tissues

The rate of randomization of linearly polarized light as a collimated polarized beam passes through scattering media was characterized by a diffusivity ((chi) ) (radians 2 /mean free path) in the angle space ((theta) ) describing orientation of the linear polarization: probability of orientation at an angle p((theta) ) equals exp[-(theta) 2 /(2(sigma) 2 )]/[(sigma) sqrt((pi) /2)] where (sigma) equals (chi) (tau ) and (tau) is the mean free path ((mu) s L) where (mu) s is the scattering coefficient (cm -1 ) and L is sample thickness (cm). The media studied were polystyrene microsphere solutions, liver, muscle, and skin. The (chi) for microspheres ranged from 0.80 - 0.03 for 300 - 6000 nm diameter, and was 0.28 for skin, 0.06 for muscle, and 0.003 for liver.
Their Day in Court: Assessing Guilty Plea Rates Among Terrorists

Individuals who are charged for traditional crimes are substantially more likely to plead guilty than individuals who are charged under the same statutes but who are officially involved in terrorism (Smith & Damphousse, 1998). Relying on a structural–contextual theory framework, a quantitative analysis not only confirmed that terrorists plead guilty more often than traditional offenders but that the defendant’s age and number of counts in the indictment are important predictors. Directions for future research are suggested.