cssi/SciSciGPT-SciSciNet huggingface dataset:
Low-cost calcium fluorometry for long-term nanoparticle studies in living cells

Calcium fluorometry is critical to determine cell homeostasis or to reveal communication patterns in neuronal networks. Recently, characterizing calcium signalling in neurons related to interactions with nanomaterials has become of interest due to its therapeutic potential. However, imaging of neuronal cell activity under stable physiological conditions can be either very expensive or limited in its long-term capability. Here, we present a low-cost, portable imaging system for long-term, fast-scale calcium fluorometry in neurons. Using the imaging system, we revealed temperature-dependent changes in long-term calcium signalling in kidney cells and primary cortical neurons. Furthermore, we introduce fast-scale monitoring of synchronous calcium activity in neuronal cultures in response to nanomaterials. Through graph network analysis, we found that calcium dynamics in neurons are temperature-dependent when exposed to chitosan-coated nanoparticles. These results give new insights into nanomaterial-interaction in living cultures and tissues based on calcium fluorometry and graph network analysis.
Linking anthocyanin diversity, hue, and genetics in purple corn.

While maize with anthocyanin-rich pericarp (purple corn) is rising in popularity as a source of natural colorant for foods and beverages, information on color range and stability-factors associated with anthocyanin decorations and compositional profiles-is currently limited. Furthermore, to maximize the scalability and meet growing demands, both anthocyanin concentrations and agronomic performance must improve in purple corn varieties. Using the natural anthocyanin diversity present in a purple corn landrace, Apache Red, we generated a population with variable flavonoid profiles-flavanol-anthocyanin condensed forms (0-83%), acylated anthocyanins (2-72%), pelargonidin-derived anthocyanins (5-99%), C-glycosyl flavone co-pigments up to 1904 µg/g, and with anthocyanin content up to 1598 µg/g. Each aspect of the flavonoid profiles was found to play a role in either the resulting extract hue or intensity. With genotyping-by-sequencing of this population, we mapped aspects of the flavonoid profile. Major quantitative trait loci (QTLs) for anthocyanin type were found near loci previously identified only in aleurone-pigmented maize varieties [Purple aleurone1 (Pr1) and Anthocyanin acyltransferase1 (Aat1)]. A QTL near P1 (Pericarp color1) was found for both flavone content and flavanol-anthocyanin condensed forms. A significant QTL associated with peonidin-derived anthocyanins near a candidate S-adenosylmethionine-dependent methyltransferase was also identified, warranting further investigation. Mapping total anthocyanin content produced signals near Aat1, the aleurone-associated bHLH R1 (Colored1), the plant color-associated MYB, Pl1 (Purple plant1), the aleurone-associated recessive intensifier, In1 (Intensifier1), and several previously unidentified candidates. This population represents one of the most anthocyanin diverse pericarp-pigmented maize varieties characterized to date. Moreover, the candidates identified here will serve as branching points for future research studying the genetic and molecular processes determining anthocyanin profile in pericarp.
Enhancing Mortgage Credit Availability Among Underserved And Higher Credit-Risk Populations: An Assessment Of Default And Prepayment Option Exercise Among Fha-Insured Borrowers

While prior analyses have provided substantial evidence of elevated default probabilities among mortgages originated to lower income, less credit worthy and minority borrowers, those risks may be offset by the reduced prepayment probabilities of those loans. To the investor in FHA-insured mortgages, such offsets could serve to appreciably reduce total loan termination risk and in so doing boost investment returns. To assess those effects, this paper employs micro-data from the FHA to estimate an option-based hazard model of the competing risks of mortgage termination. The empirical model derives from option theory and includes controls for mortgage put and call options, borrower credit worthiness, and a large number of other contemporaneous and time-invariant indicators of borrower, loan, and locational risk. Results of the analysis indicate that the elevated default probabilities of loans originated to lower credit quality and minority borrowers are more than offset by their reduced prepayment risks. The estimated cumulative probability of mortgage termination among lower credit-quality and African-American borrowers is only about three-fourths that of higher credit-quality and white borrowers, respectively. Recognition of this mortgage performance advantage should enhance the willingness of lenders and investors to originate and acquire such loans and at more competitive pricing. Findings suggest that the extension of mortgage credit to less credit-worthy and underserved borrowers, in a manner consistent with their lower termination risks, would serve to advance both their homeownership opportunities and related federal housing policy objectives.
Reverse Phase HPLC Separation of Cis-and Trans-Carotenoids and Its Application to β-Carotenes in Food Materials

Abstract Four trans-carotenoids, β-carotene, α-carotene, lutein and lycopene, were isomerized with light energy under iodine catalysis and the isomeric mixtures were subjected to reverse phase chromatography on a 5μ VYDAC TP-201 column with mobile phases of methanol-chloroform to separate the major isomers. The amounts and properties of the cis-compounds conformed with separations obtained by others from lime and alumina columns. In each case, the predominant isomers behaved as 13-cis-and 9-cis-isomers, except for the lycopene set which included isomers not previously separated. Use of the system for rapid analysis of 13-cis, 9-cis-and trans-β-carotene in some common food materials was demonstrated. The percentage of cis-isomers in the β-carotene fraction ranged from 1.6 in raw carrot to 29.6 in canned peach.
Pilot assisted coherent DS-CDMA reverse-link communications with optimal robust channel estimation

Optimal pilot assisted estimation of communication channels is considered for coherent cellular and PCS CDMA reverse link communications. Both pilot symbol and pilot channel based schemes are described and the optimal estimators for these two schemes are analyzed. Relative mean square estimation error (RMSEE) and optimal power allocation between data and pilot signals are derived based on the analysis. Finally, simulation results are given to show the reverse link performance can be significantly improved by using the pilot assisted coherent communication instead of non-coherent schemes for the CDMA reverse link.
Influence of Fluorine on the Electrochemical Performance of Spinel LiMn2 − y − z Li y Zn z O4 − η F η Cathodes

Spinel LiMn 2-y-z Li y Zn z O 4-η5 F η (0 ≤ y ≤ 0.1, 0 ≤ z ≤ 0.1, and 0 ≤ η ≤ 0.18) cathodes have been synthesized by solid-state reactions at 800°C, employing ZnF 2 to prepare the oxyfluorides and ZnO to prepare the oxides. Although the LiMn 2-y-z Li y Zn z O 4 samples show a significant improvement in electrochemical performance compared to LiMn 2 O 4 , the oxyfluoride cathodes LiMn 2-y-z Li y Zn z O 4-η F η exhibit better capacity retention with an increase in capacity of up to 10 mAh/g compared to the corresponding oxide analogs LiMn 2-y-z Li y Zn z O 4 . The superior electrochemical performances of the LiMn 2-y-z Li y Zn z O 4-η F η oxyfluoride cathodes are found to be due to a suppression in manganese dissolution, smaller lattice parameter difference Aa between the two cubic phases formed during the charge-discharge process, lower microstrain, and maintenance of good crystallinity during cycling.
Using Literacy to Understand Mexican Boys' Perspectives of Life.

Many nine- and ten-year-old boys find reading interesting but begin to feel insecure about themselves as readers and avoid reading whenever they can. Reading avoidance starts early and for many boys, especially those of color living in poverty, fourth grade seems to be the time when this downward spiral begins. National and state assessment data consistently and currently indicates a gap and stall in the reading achievement of male Latino and English Language Learners living in poverty. However, as Weaver-Hightower (2008) notes, when educators talk about boys and their literacy achievement, they must not only ask which boys are failing but must also ask why ? The goal of this study was to answer the why to Weaver-Hightower’s questions for Mexican boys living in Phoenix, Arizona in the early part of 2010. Toward this goal, we established a fourth grade boys’ book club in a neighborhood which presented many challenges for its inhabitants but especially for the Mexican boys who were learning English at their local school. Immigration sweeps and State Bill 1070 permeated their lives and skewed their vision of academic and social success. Regardless, our book club members emerged as tolerant, courageous, and generous individuals who do enjoy reading but too often find themselves reading alone. From these findings implications for educators are provided.
Kaposi's Sarcoma–Associated Herpesvirus/Humanherpesvirus 8 (KSHV/HHV‐8)

This article has no abstract. Keywords: kaposi's sarcoma–associated herpesvirus/humanherpesvirus 8 (KSHV/HHV-8)
Geographical distribution of a neutral allele considered as a branching process

Abstract The limiting spacial correlations are derived for a population of neutral alleles migrating among K colonies. The allelic population is modeled as a subcritical branching process and the limiting correlations are obtained conditional on nonextinction of the population.
A Parametric Study Of Mesh Enhanced Forced Convection Heat Transfer For The Cooling Of High Power Density Mirrors

By sandwiching a single layer of wire screen mesh mechanically between two surfaces, a simple heat transfer enhance-ment mechanism has been demonstrated recently (Fleishman and Yuen, 1988) to be effective for general high heat flux applications. Average heat transfer coefficients of up to 9.5 W/cm2K were measured for a smooth plane surface cooled by water. Based on a first-order mathematical model, the enhancement factor was shown to be a function of mesh wire diameter, thermal conductivity, screen pitch, surface heat transfer coefficient, and a non-dimensional thermal contact resistance. In this work, additional data are generated to further understand quantitatively the performance characteristics of the mesh-enhanced heat transfer mechanism. Specifically, average heat transfer coefficients ranged between 0.7 to 6.2 W/cm2K are measured for three different screen materials (brass, stainless steel, and copper) in a 26 cm2 fixture cooled by city water under line pressure. Heating rates range from 200 to 350 kW/m2 and flow rates from 0.004 to 0.086 kg Is . Effect of macroscopic screen parameters such as thermal conductivity, the weaving pattern of the wire and the "flatness" of the screen are investigated. The mathematical model is further developed to predict parametrically the optimized conditions for maximum heat transfer. The applicability of the present mesh-enhanced heat transfer mechanism for the cooling of high power density mirrors is assessed.
The organization of spatial frequency maps measured by cortical flavoprotein autofluorescence

To determine the organization of spatial frequency (SF) preference within cat Area 17, we imaged responses to stimuli with different SFs using optical intrinsic signals (ISI) and flavoprotein autofluorescence (AFI). Previous studies have suggested that neurons cluster based on SF preference, but a recent report argued that SF maps measured with ISI were artifacts of the vascular bed. Because AFI derives from a non-hemodynamic signal, it is less contaminated by vasculature. The two independent imaging methods produced similar SF preference maps in the same animals, suggesting that the patchy organization of SF preference is a genuine feature of Area 17.
Future end-of-life care: partnership and advocacy.

THE FIELD OF END-OF-LIFE CARE may be evolving into a new phase. There has been remarkable progress in the past two decades, and now there is a respectable body of advanced knowledge in palliative care to give rise to a whole new subspecialty. However, the practice of end-of-life care still faces an uphill struggle against the conventional, technologically driven health care system. Even among a gathering of leaders in the field, there was a sense shared by many if not most, that end-of-life care still is, and continues to be, a “fringe” discipline outside mainstream healthcare. The question was asked: What are the next steps to realize the vision that palliative care principles should occupy the center stage of medicine and play a key role in how we care for the majority of patients with chronic disabling diseases, in hospital wards, intensive care units, operating rooms, emergency departments as well as hospices, nursing homes, and patients’ homes? Throughout the seminar, the participants wrote their responses to the above question, which were then collated and categorized into four broad categories: multisector collaboration, financing, professional education, and advocacy. In the final session of the last day, entitled Strategies and Actions, the participants discussed— with a bird’s-eye view—the necessary steps that must be taken to realize the above vision. It is always risky to paraphrase or interpret the oral arguments stated by others. The source for the following discussion obviously belongs to the participants,* although any misrepresentation may be ascribed to the author. The following is neither a consensus opinion nor an exhaustive list of future strategies in end-of-life care. Rather, it is offered as a summary of individual opinions to stimulate further exploration. What emerged from the final session is as follows. For the end-of-life care movement to cast a wider net and “institutionalize” its agenda in future American health care, the relatively small but rapidly expanding network of dedicated clinicians, researchers, patient advocates and private funders must pursue their reform efforts through partnership and advocacy.
Psychological impact of recall in high-risk breast MRI screening.

Purpose To address the widespread concern that false-positive results during breast MRI screening may have adverse psychological effects. Methods Impact of Event Scale measurements in 103 high-risk women enrolled in a longitudinal MRI screening study and comparison of subjects with normal results vs. those with prior recall events. Results Of 189 MRI scans performed, 64 (34%) prompted further evaluation. Subjects with previously abnormal results had significantly higher Avoidance scores at the time of their second MRI. Multivariate analysis showed this was driven by the greater number of BRCA1/2 carriers in that group but was not related to screening recall. Conclusions Practitioners’ concerns about the high false positive rate of breast MRI may not be matched by actual psychological effects in most high-risk women.
Nephrotoxicity of phenolic bromobenzene metabolites in the mouse.

Bromobenzene, at doses greater than 5.7 mmol/kg, produced renal proximal tubular necrosis and renal functional changes in mice. p-Bromophenol and o-bromophenol were the major urinary phenolic bromobenzene metabolites although m-bromophenol and 4-bromocatechol were also excreted in detectable quantities. With the exception of o-bromophenol, urinary metabolites were excreted primarily as conjugates. 4-Bromocatechol and the 3 bromophenol isomers were nephrotoxicants (measured as increased blood urea nitrogen and decreased accumulation of organic anions by renal cortical slices) but not hepatotoxicants (measured as serum glutamic pyruvate transaminase) in vivo at 0.56 mmol/kg (i.v.). Preincubation of renal cortical slices with each of these bromobenzene metabolites for 90 min resulted in dose-dependent decreases in the accumulation of p-aminohippurate and tetraethylammonium. At 10 mumol/preincubation (2.4 mM), organic ion accumulation was decreased maximally by all bromobenzene metabolites examined while equimolar amounts of bromobenzene were without effect. 4-Bromocatechol was the most potent nephrotoxicant in vitro. Administration of 0.53-2.12 mmol/kg (i.v.) 4-bromocatechol to mice resulted in a dose-dependent decrease in renal function while hepatic function was altered only slightly at the higher doses. The renal cortical necrosis produced by in vivo administration of 4-bromocatechol could not be distinguished histologically from that induced by bromobenzene. These results demonstrate that 4-bromocatechol and the 3 bromophenol isomers are nephrotoxicants that can be generated from bromobenzene in mice.
Changes in nutrient composition and pH of the culture medium during in vitro shoot proliferation of crabapple and pear

Shoot tips of Seckel pear and Almey crabapple were cultured on liquid MS medium containing 8.8 μM BA. Changes in shoot proliferation and growth and in nutrient and carbohydrate composition of the medium were determined during a 9 week culture period. Whereas shoot proliferation in crabapple increased linearly during the culture period, it levelled off after week 4 in pear. Explant dry weight in both genera showed a linear increase over time. Culture medium pH decreased in the initial weeks and increased thereafter. There was a rapid decline in medium P and Fe concentration with both genera and of Zn in the medium of crabapple. In no instance did the rate of depletion of any nutrient from the medium of pear cultures exceed that measured in the crabapple medium. The decline in sucrose concentration in the medium was similar for both genera and was accompanied by an increase in the level of glucose and fructose. At the end of the culture period slightly over half of the initial carbohydrate level remained in the medium.
The Plausibility of Homeopathy: The Systemic Memory Mechanism

Abstract Despite 200 years of practice of high dilution therapy known as homeopathy, and despite a number of recent studies documenting homeopathic treatment effects under double-blind conditions, the medical and scientific community has generally dismissed these findings because of a lack of a plausible mechanism for the observed effects. This article outlines how modern systems science reenvisions memory in water and dynamic systems in general. We present the logic that inexorably leads to the prediction that recurrent feedback interactions result in the storage of information and the creation of systemic memories in dynamic systems at all levels in nature. The complex nonlinear interactions that naturally accumulate through the circulation of information and energy in systems are shown to be dynamic memories that reflect the evolving identity of systems as emerging wholes. The theory provides a highly plausible mechanism for understanding numerous seemingly implausible and controversial observations in contemporary science and medicine, including memory in water and homeopathy.
Transient Moderate Bilateral Maternal Hydronephrosis at 7 Weeks Gestation Resolving Imzmediately After Micturition

A case in which moderate bilateral maternal hydronephrosis was documented sonographi cally at 7 weeks0 gestatio, and resolved spontane ously immediately after micturition, is presented. This occurr...
Cancer in Inflammatory Bowel Disease.

Colorectal cancer (CRC) is a complication in both patients with longstanding ulcerative colitis and those with Crohn’s disease. As with sporadic CRC, surgical therapy (with adjuvant chemotherapy in advanced disease) is the only effective treatment. Identifying risk factors for CRC in inflammatory bowel disease (IBD) should allow patients to receive appropriate medical, endoscopic, and surgical care to minimize CRC morbidity and mortality. Total proctocolectomy remains the most effective form of cancer prophylaxis in IBD patients, but because of the impact of this approach and the low absolute risk of cancer, clinicians seldom recommend it. Colonoscopic surveillance with systematic biopsies is used to detect mucosal dysplasia and thus identify those patients at greatest risk for developing CRC. Patients with dysplasia other than that in readily excised polyps should be referred for surgery. Although fraught with limitations, surveillance is the best method currently available for reducing CRC mortality and morbidity short of prophylactic colectomy. It will have to remain the standard of practice until better diagnostic tests are available. Surveillance should be offered and performed in the same manner for patients with Crohn’s disease and ulcerative colitis. Chemoprevention may prove effective in the future, but currently used agents have only a modest benefit, if any. Adenocarcinoma of the small intestine occurs at an increased rate in patients with Crohn’s disease of the bowel with longstanding small bowel involvement, but there are no current methods of early detection. Treatment is based on disease identified from evaluation of symptoms or incidental finding. Some extraintestinal cancers have been noted to occur at increased rates in series from referral centers but not in population-based studies.
A role of auxin in phloem regeneration in Coleus internodes

Abstract The physiology of regenerative phloem formation in the number 5 internode of Coleus blumei Benth. was studied by estimating quantitatively its extent in plants or plant parts wounded so as to sever one or more of the existing phloem bundles and then allowed to regenerate for a short period (usually 5 days). Removal of all leaves and buds from plants resulted in a marked reduction (to approximately one-quarter of the value of the intact controls) in phloem regeneration. Primary leaf removal also resulted in some, though a smaller, reduction, as did the one other treatment—removal of all distal organs—which involved removal of young primary leaves. The other patterns of shoot organ removal tried—all buds removed and all proximal leaves and buds removed—had no effect on phloem regeneration. Indoleacetic acid (IAA) applied in aqueous solution (2 mg/l) to plants from which all leaves and buds had been removed completely substituted for them in phloem regeneration. Applied in lanolin paste (0.1% and 1%), it evoked more phloem regeneration than attached organs themselves. Sucrose (2%) applied alone or together with IAA in aqueous solution had no effect. IAA (0.1%) applied in lanolin to excised internodes increased phloem regeneration in these, but the anomalous appearance of some of the wound sieve tubes indicated that sugar or other material may have become limiting for full differentiation. A relationship between the number of phloem bundles cut in wounding and the extent of phloem regeneration was shown. This and other observations were interpreted as indicating the involvement in phloem regeneration of a substance or substances leaking from the cut phloem. Existing evidence is interpreted to mean that auxin is limiting for the cell divisions which immediately precede phloem differentiation and that some other factor, presently unknown, may be limiting for differentiation when auxin is in sufficient supply for cell division. However, present evidence neither implies nor excludes the possible participation of auxin in differentiation itself.
Breath Hydrogen Reflects Canine Intestinal Ischemia

Summary: The relationship between breath hydrogen excretion and intestinal ischemia was investigated in nine mechanically ventilated dogs under pentobarbital anesthesia. An ileal segment was isolated in situ, ligated at each end, and insufflated with hydrogen. Expired air was collected at intervals. Blood volume was reduced 30% by three successive equivalent hemorrhages 10 min apart. Local bowel ischemia was produced by clamping the blood supply to the isolated segment for 10 min. Graded hemorrhage produced stepwise reductions in breath hydrogen concentration, to 77 ± 13, 66 ± 15, and 35 ± 8% (mean ± S.E.) of baseline after the first, second, and third hemorrhages, respectively. These reductions correlated highly (r = 0.84; P < 0.01) with declines in mean aortic blood pressure. Occlusion of blood supply caused a significant (P < 0.025) decrease in breath hydrogen concentration and excretion to 39 ± 14% of baseline. Termination of occlusion was followed within 2 min by a 7-fold increase in breath H2 concentration above the original baseline, probably reflecting reactive hyperemia. Breath hydrogen measurements appear to reflect functional (hemorrhagic shock-induced) and mechanical (vascular occlusion induced) enteric ischemia in dogs. Speculation: Monitoring of breath Hz excretion in the infant at risk for necrotizing enterocolitis may indicate the development of enteric hypoperfusion. Inhibition of transfer of Hz into the portal circulation in the presence of reduced mesenteric blood flow may contribute to distention of the bowel in necrotizing enterocolitis and further impede intestinal perfusion.
Reflection properties of the core‐mantle boundary from global stacks of PcP and ScP

[1] Seismic phases that reflect off the core-mantle boundary (CMB) are sensitive to the velocity and density contrasts between the base of the mantle and the core. We measure the amplitudes of CMB reflections to seek effects of large velocity reductions and possible density increases in proposed thin basal layers (ultralow-velocity zones, or ULVZs). We construct globally averaged envelope stacks of PcP and ScP in 3� -wide epicentral distance bins, correcting for propagation and source effects. We measure the amplitude ratios PcP/P and ScP/P and compare them with the predicted range dependence for preliminary reference Earth model (PREM) and several proposed ULVZ models. The amplitude ratios are not compatible with ULVZs containing 30% S wave velocity reductions or with a 3-km-wide core-mantle transition zone. The PcP data cannot distinguish between PREM and models with 10% reductions in both P wave velocity (VP) and S wave velocity (VS) and up to a 20% increase in density. The ScP data also match PREM closely but contain greater uncertainty from the correction for mantle attenuation. In well-sampled regions, lateral variations of reflection amplitudes mapped to bounce point locations are consistent with previous detections and nondetections of ULVZs. These results suggest that extreme velocity reductions near the CMB are not global features and that regions with large velocity reductions do not result from global phenomena such as phase changes in an isochemical mantle but rather from local thermal or compositional anomalies. INDEX TERMS: 7203 Seismology: Body wave propagation; 7207 Seismology: Core and mantle; 8124 Tectonophysics: Earth’s interior—composition and state (1212); KEYWORDS: core-mantle boundary, ultralow-velocity zones, PcP, ScP Citation: Persh, S. E., and J. E. Vidale (2004), Reflection properties of the core-mantle boundary from global stacks of PcP and ScP, J. Geophys. Res., 109, B04309, doi:10.1029/2003JB002768.
A survey of cancer support groups provided by national cancer institute (NCI) clinical and comprehensive centers

The 42 National Cancer Institute Clinical and Comprehensive Cancer Centers were surveyed about their group support programs. All responding centers (81%) offered group support programs, an average of 3.5 groups per center. There were an average of 6.0 members per group. About an equal number of groups were composed of patients or family members only; more groups included both patients and family members. About one-third of the groups were limited by site, most commonly breast cancer. One-quarter limited membership by treatment, and a few groups limited membership by stage of disease. Most of the groups were open-ended in structure. Nearly all groups met with a frequency between weekly and monthly. Support and education were the primary focus of groups, rather than cognitive-behavioral or psychotherapy. Social workers and nurses led the majority of groups. Almost all of the groups were provided without payment. Implications of the survey's findings for research and clinical applications of support groups for cancer patients are discussed.
The isolation and identification of 4-methylthiazole-5-acetic acid as a metabolite of thiamine inPhycomyces blakesleeanus

Abstract The thiamine metabolite 4-methylthiazole-5-acetic acid (thiazole acetic acid) has been isolated and identified from broth cultures of Phycomyces blakesleeanus . Preliminary evidence indicates that NADP + -dependent alcohol dehydrogenase is involved in the formation of thiazole acetic acid.
Electric Propulsion Space Experiment (ESEX) On-Orbit Results

The U.S. Air Force Research Laboratory's Electric Propulsion Space Experiment was launched and successfully operated, demonstrating the compatibility and readiness of a 26-kW ammonia arcjet subsystem for satellite applications. The Electric Propulsion Space Experiment is one of nine experiments on the U.S. Air Force's Advanced Research and Global Observation Satellite. Data were acquired to characterize the thruster in four different areas: electromagnetic interactions, contamination effects, optical properties of the plume, and thruster system performance. The results demonstrated that the critical system components including the arcjet, power processor, and propellant system operated well and verified the interoperability of high-power electric propulsion with generic satellite operations.
High temperature pyrolyses of acetylene and diacetylene behind reflected shock waves

A time-of-flight mass spectrometer coupled to a shock tube was used to study the thermal decompositions of C2H2 and C4H2 over the temperature range 1880–2620 K at total reflected shock pressures of ∼ 0.4 atm. Comparison of the experimental results obtained from 3.2% C2H2 mixtures, one of which contained synthesized, acetone-free acetylene, and the other comprised of purified tank acetylene containing 30 ppm acetone, reveals no discernible differences in the reaction profiles. The results are modeled satisfactorily with a new 40 step reaction mechanism which incorporates a recently proposed value for ΔfH0(C2H) of 130.4 kcal/mol. The concentration profiles obtained for C2H2, C4H2 and C6H2 are not affected by inclusion of molecular reactions in the mechanism over the temperature range covered herein. The rate employed for the dominant chain initiation at moderate temperatures, 2 C2H2→ C4H3+H, is that calculated from an RRKM analysis of new measurements on the dissociation of vinylacetylene. Strongly non-Arrhenius rate constants are employed for the crucial reaction, C2H+H2→C2H2+H, which exceed previous estimates by more than a factor of three at 2000 K. Additional support for the mechanism is provided by the kinetic data obtained from mixtures containing C4H2 as an initial reagent. It is concluded that a fragment chain reaction mechanism is clearly dominant in the high temperature region.
Risk Management and Risk Preferences in Agriculture: Discussion

I would like to commend the authors of both papers delivered in this session. The papers deal with important topics that deserve our attention. Because my major interest in this area has been the representation of economic agents' beliefs (see Bessler, and Bessler and Moore), I find it appropriate to direct the bulk of my comments to the paper delivered by Young. My comments on the paper by Mapp, Hardin, Walker, and Persaud will reflect only methodological points. Briefly, the paper by Young reviews several empirical works on the elicitation of economic agents' risk preferences and makes certain observations on the feasibility of incorporating these preferences in various extension and research applications. The paper by Mapp et al., describes the selection of alternative risky production and management strategies using a variant of the mean-variance analysis for a southwestern Oklahoma farm operation. Outcomes from this analysis are then simulated, under alternative equity and price assumptions, over a twenty-year period. My primary concern with both papers is that they have, for the most part, ignored the problems associated with using variance as a measure of risk and the associated stochastic dominance literature. The concern is quite real for the paper by Mapp et al., because their results are directly based on the representation of risk by variance (or an approximation of variance). My concern also applies to Young's paper. He too directs his discussion to the traditional mean-variance analysis of risky choice. Although he suggests that other procedures might apply, such as Meyer's stochastic dominance theorems, he gives only passing mention of their use in research and extension programs. Criticisms of the mean-variance approach to analysis of risky choice have been heard for some time-probably the most elegant of these
Millet Processing for Improved Stability and Nutritional Quality Without Functionality Changes

Whole millet adjusted to 15% moisture was gradually heated to 97°C over 12 min by passing through a steam-jacketed paddle conveyer to inactive lipid enzymes. Both processed and unprocessed millet were milled to 50% and 80% extraction flours. The 80% flour contained germ fractions, which resulted in much higher protein, lipid, thiamine, riboflavin, niacin, iron, zinc, available lysine, and protein efficiency ratios than the 50% flour. After 49°C storage, peroxide and fat acidity values were lower and flavor scores higher for processed than for unprocessed millet flours. No differences between processed and unprocessed flours were found in birefringence, water absorption and solubility, viscoamylograph values, or in their use in several traditional foods.
The electrostatic potential of a discretely charged cylinder in solution

The electrostatic potential of an infinitely long cylinder with a periodic, discrete charge density was calculated, assuming the cylinder was immersed in a simple 1 : 1 electrolyte solution. The charge density of the simple electrolyte was taken to be the linearized Debye-Huckel charge density. It was also assumed that the discrete charge density, was within the cylinder (rather than on its surface), and that the interior of the cylinder had a unique dielectric constant Dh, which was treated as a parameter. Although this model (except for the Debye-Huckel assumption) more realistically represents DNA than previous models, the calculated potential was found to be ambiguous, depending on the value chosen for the depth of the discrete charge below the cylinder surface. However it was also found that the dependence of the potential on the simple electrolyte concentration was well-defined and was identical to that of a continuously charged cylinder. It was concluded that the continuously charged cylinder model adequately describes differential salt effects.
Non-bonded intra-molecular interactions in 1,8-disubstituted naphthalenes with a cyano group as the electrophilic substituent

Ab initio, self-consistent field, molecular-orbital, calculations were carried out for two 1,8-disubstituted naphthalene compounds to probe non-bonded, intra-molecular, interactions between electrophilic and nucleophilic substituents located at the 1 and 8 positions of the naphthalene rings. The cyano (–CN) group is the electrophilic substituent; the cyano carbon atom is the electrophilic center. The nucleophilic substituents were each, a nitro (–NO2) group in compound I, and a methoxy (–OCH3) group in compound II. The X-ray structure showed that the nitro-nitrile compound existed as two distinct structures, each with different bond distances and bond-angles of the peri substituents. We probed the nature of intra-molecular interactions in these compounds by calculating the electronic charges and molecular electrostatic potentials adjacent to the substituents. Similar studies for carbonyl group as the electrophilic substituent indicated the presence of electronic interactions for naphthalene compounds with the carbonyl group as the electrophilic substituent.
A global view of gene expression in the preimplantation mouse embryo: morula versus blastocyst

As a first step to understand preimplantation development, we performed global gene-expression profiling of morula and blastocyst using the NIA 15k mouse cDNA microarray. Gene expression levels were measured four times for blastocyst and five times for morula. Student’s ttest at the 5% significance level identified 428 genes upregulated and 748 downregulated in blastocyst compared to morula. This trend was consistent with semi-quantative RT-PCR analysis of sample genes. The upregulated genes known to be involved in critical regulatory processes, included Mist1, Id2, Hd1, and Requiem; the downregulated genes included CREB-binding protein, Per3, zinc finger protein 217, Krox-25, and miwi1. Such well-characterized genes and many novel genes provide markers for early stages in development and starting materials for further functional studies. Published by Elsevier Ireland Ltd.
Functional defects in lysosomal enzymes in autosomal dominant polycystic kidney disease (ADPKD): abnormalities in synthesis, molecular processing, polarity, and secretion.

Abstract The phenotype of autosomal dominant polycystic kidney disease (ADPKD) is characterized by basement membrane abnormalities, hyperproliferation, and alterations in epithelial cell polarity. Since proteinases have been implicated in matrix degradation and growth factor activation, lysosomal enzymes were compared in normal and ADPKD tissues and cell cultures. Acidic proteolytic activity (azocasein) was reduced in ADPKD, and specific enzymatic assays detected disease-dependent decreases in the specific activities of β-galactosidase, β-hexosaminidase, and cathepsins, B, L, and H. Cathepsin D-specific activities were unchanged. Lucifer yellow fluorescence in ADPKD cells was consistent with an alteration in heterogeneity of lysosomal enzyme content in ADPKD rather than a decrease in total lysosomal number. Western analysis, metabolic labeling, and immunoprecipitation analysis confirmed decreases in the expression and synthesis of the major normal molecular immunoreactive species of β-galactosidase and cathepsins B and H in ADPKD tissue and cells but no changes in cathepsin D. In addition, ADPKD-specific high-molecular-weight species of cathepsin H were seen and abnormal forms of cathepsin B and β-galactosidase were common in ADPKD, suggesting abnormal molecular processing and posttranslational modifications. In addition, immunolocalization studies showed abnormal apical plasma-membrane localization of cathepsins B and H in ADPKD cyst epithelial cells, consistent with a protein sorting defect in ADPKD. Increased extracellular secretion of lysosomal enzymes was also measured in ADPKD cultured cells and in filter-grown epithelia shown to be predominantly directed to the basal compartment. These results demonstrate that lysosomal enzyme alterations in ADPKD may play a role in aberrant processing of the basement membrane. Alterations in the polarized secretion of lysosomal enzymes by ADPKD epithelia in vitro were also detected. Whereas all normal epithelia cells secreted lysosomal enzymes predominantly to the apical medium compartments, basally directed secretion was increased in all ADPKD epithelia and attained an overall reversal of polarity for cathepsins B + L. It is concluded that alterations in lysosomal enzyme function in ADPKD are the result of alterations in synthesis, molecular processing, and polarized secretion of specific enzymes and may have impact on proliferative and basement membrane abnormalities in this genetic disease. These results are consistent with a fundamental defect in protein processing, sorting, and trafficking in ADPKD.
Antagonistic Interactions among Marine Pelagic Bacteria

Recent studies suggest that bacterial abundance and species diversity in the ocean's water column are variable at the millimeter scale, apparently in response to the small-scale heterogeneity in the distribution of organic matter. We hypothesized that bacterium-bacterium antagonistic interactions may contribute to variations in community structure at the microscale. We examined each of the 86 isolates for their inhibition of growth of the remaining 85 isolates by the Burkholder agar diffusion assay. More than one-half of the isolates expressed antagonistic activity, and this trait was more common with particle-associated bacteria than with free-living bacteria. This was exemplified by members of the α subclass of the class Proteobacteria (α-proteobacteria), in which production of antagonistic molecules was dominated by attached bacteria. We found that γ-proteobacteria (members of the orders Alteromonadales and Vibrionales) are the most prolific producers of inhibitory materials and also the most resilient to them, while members of the Bacteriodetes were the organisms that were least productive and most sensitive to antagonistic interactions. Widespread interspecies growth inhibition is consistent with the role of this phenomenon in structuring bacterial communities at the microscale. Furthermore, our results suggest that bacteria from pelagic marine particles may be an underutilized source of novel antibiotics.
Thyroid function abnormalities during amiodarone therapy for persistent atrial fibrillation.

Abstract Background Many patients receiving amiodarone therapy are male. The long-term risk for amiodarone-induced thyroid dysfunction in these patients has not been systematically and prospectively investigated. The purpose of this study was to determine the extent of amiodarone-induced thyroid dysfunction in a large male cohort. Methods This is a substudy of a prospective randomized controlled trial (SAFE-Trial) in which amiodarone, sotalol, and placebo for persistent atrial fibrillation were evaluated. For the purpose of this substudy, sotalol and placebo groups were combined into a control group. Serial thyroid function tests were performed over 1-4.5 years. Of the 665 patients enrolled in the SAFE-Trial, 612 patients were included in this sub-study. Results Subclinical hypothyroidism, thyroid-stimulating hormone (TSH) level 4.5-10 mU/L, was seen among 25.8% of the amiodarone-treated patients and only 6.6% of controls ( P 10 mU/L, was seen among 5.0% of the amiodarone-treated patients, and only 0.3% of controls ( P P =.07). Conclusions Hypothyroidism developed in 30.8% of older males treated with amiodarone and in only 6.9% of the controls. Hypothyroidism presented at an early stage of therapy. Hyperthyroidism occurred in 5.3% of amiodarone treated patients, and was a subclinical entity in all but 1 case.
Investigation of the pH dependence of proton uptake by porcine heart mitochondrial malate dehydrogenase upon binding of NADH.

Abstract The pH dependence of proton uptake upon binding of NADH to porcine heart mitochondrial malate dehydrogenase ( l -malate: NAD + oxidoreductase, EC 1.1.1.37) has been investigated. The enzyme has been shown to exhibit a pH-dependent uptake of protons upon binding NADH at pH values from 6.0 to 8.5. Enzyme in which one histidine residue has been modified per subunit by the reagent iodoacetamide ( E. M. Gregory, M. S. Rohrbach, and J. H. Harrison, 1971, Biochim. Biophys. Acta 253 , 489–497 ) was used to establish that this specific histidine residue was responsible for the uptake of a proton upon binding of NADH to the native enzyme. It has also been established that while there is no enhancement of the nucleotide fluorescence upon addition of NADH to the iodoacetamide-modified enzyme, NADH is nevertheless binding to the modified enzyme with the same stoichiometry as with native enzyme. The data are discussed in relation to the involvement of the essential histidine residue in the catalytic mechanism of “histidine dehydrogenases” recently proposed by Lodola et al. ( A. Lodola, D. M. Parker, R. Jeck, and J. J. Holbrook, 1978, Biochem. J. 173 , 597–605 ) and the catalytic mechanism of “malate dehydrogenases” recently proposed by L. H. Bernstein and J. Everse (1978, J. Biol. Chem. 253 , 8702–8707 ).
Serum luteinizing hormone, 13,14-dihydro-15-keto-prostaglandin F2α and cortisol profiles during postpartum anestrus in Brahman and Angus cows

Pluriparous suckled Brahman and Angus cows were utilized to evaluate the effect of breed, day after calving and endogenous opioid peptides (EOP) on hormonal profiles during postpartum anestrus. On Days 17 and 34 after calving, blood samples with and without heparin were collected at 15- and 30-min intervals, respectively, for a 7-h period via jugular cannula. Two hours after the start of blood sampling, cows of each breed were administered either 1 mg/kg iv naloxone or saline. Three hours later, all animals received 10 ng/kg iv GnRH. On Day 34 after calving cows received 0.2 IU/kg iv ACTH. Mean LH, basal LH and area under the LH curve increased (P < 0.01) from Day 17 to Day 34 after calving. Height of LH pulses increased (P < 0.05) by Day 34 after calving. Brahman cows had higher (P < 0.05) mean LH, basal LH, LH pulse frequency and area under the LH curve than Angus cows. Naloxone increased postchallenge area under the LH curve in treated cows above that of control cows (P < 0.06). Naloxone also increased the postchallenge area under the LH curve above that of the prechallenge level (P < 0.01). No breed differences in the response to the naloxone challenge were observed. The LH response to naloxone challenge occurred earlier on Day 34 than on Day 17 after calving but the amount of LH released was similar between days. The GnRH-induced LH release was greater in Brahman than in Angus cows (P < 0.04). Mean cortisol concentrations and area under the cortisol curve decreased (P < 0.05) between Day 17 and Day 34 after calving. Mean cortisol concentrations and area under the cortisol curve were lower (P < 0.01) in Brahman than in Angus cows. Cortisol secretion after ACTH treatment was similar between Brahman and Angus cows. The cortisol response after ACTH challenge was positively correlated (r=0.68; P < 0.001) to the prechallenge area under the cortisol curve. Under optimal environmental conditions Brahman cows have a greater LH release and their anterior hypophysis is more sensitive to GnRH challenge than the Angus cows.
English Studies as Creole Scholarship: Reconfiguring the Discipline for Postcolonial Conditions

The shifts underway in contemporary social conditions call for a new alignment between the specializations constituting English Studies: namely, literature, applied linguistics, and rhetoric and composition. Postcolonial social movements have generated new language, textual, and literary practices. These developments bring to the fore practices that have always characterized communication, but ignored in English Studies because dominant paradigms have not been sensitive to these practices. Influenced by modernist values, English Studies took on a trajectory that isolated the object of analysis in order to identify the finite rules that capture the core of communicative practices. Postcolonial communicative conditions draw attention to liminalities, flows, and mixtures that require a situated, multimodal, and multisensory understanding of languages and texts, and the plurality of meanings that emerge from a negotiation of diverse contexts. To understand such language practices, students and scholars have t...
Changes in phospholipid composition and calcium flux in LLC-PK cells cultured at low magnesium concentrations.

Abstract Monolayers of porcine kidney cells (LLC-PK) were grown in a series of Nu-Serum-supplemented media containing different Mg 2+ concentrations (480, 250, 25, 6.3 or 2.6 μM) to study the effect of Mg 2+ depletion on cellular phospholipid changes and the consequent effect on the membrane permeability to Ca 2+ . Cells grown on 6.3 or 2.6 μM Mg 2+ showed a decrease in PE, PS, Sph, PI and an increase of PC. These changes were attributed mainly to the decreased rate of Sph synthesis through the transfer of phosphocholine from PC to ceramide, or due to the increase of PE N -methylation as found in Mg 2+ -deficient cells. The 45 Ca uptake was increased in cells grown on 25.0 μM Mg 2+ , while it was decreased in cells grown on 6.3 or 2.6 μM Mg 2+ . These changes in Ca 2+ uptake were related to changes of cellular phospholipids and fatty acids which affect adenylate cyclase activity in the membrane, as well as the membrane fluidity.