cssi/SciSciGPT-SciSciNet huggingface dataset:
Interlaboratory comparison of amino acid enantiomeric ratios in Pleistocene fossils

Abstract It has been nearly three decades since the last systematic interlaboratory comparison of amino acid racemization (AAR) measurements among active laboratories. The advent of new methods and improved instrumentation for existing techniques requires that these comparisons be conducted more frequently than has occurred. The present study represents a first step in this process. Five homogeneous liquid samples were distributed to six participating laboratories that use one or more of the following analytical methods: Ion-exchange liquid chromatography (IEx), Reverse-phase liquid chromatography (RP), or Gas chromatography (GC). The five samples have been used in previous formal or informal interlaboratory comparisons: three are Pleistocene mollusk samples, two are Pleistocene eggshell samples. Use of homogeneous liquids eliminated variables involved in the majority of the sample preparative steps (sample cleaning, hydrolysis, desalting), so any observed variability between laboratories can be attributed to instrumental factors or possible small effects associated with the hydration procedures employed prior to instrumental analysis. Although most results indicate good agreement (within 10%) for all amino acid d / l values, there are some notable exceptions for certain amino acids or certain samples. For the five amino acids that are most commonly used in geochronological applications (Asx, Glx, Leu, Val, and A/I), inter-method comparisons reported here provide quantitative regressions that can be used when results from one method are compared with those from another.
Changes in the dielectric properties of a plant stem produced by the application of voltage steps

Time Domain Dielectric Spectroscopy (TDDS) provides a useful method for monitoring the physiological state of a biological system which may be changing with time. A voltage step is applied to a sample and the Fourier Transform of the resulting current yields the variations of the conductance, capacitance and dielectric loss of the sample with frequency (dielectric spectrum). An important question is whether the application of the voltage step itself can produce changes which obscure those of interest. Long term monitoring of the dielectric properties of plant stems requires the use of needle electrodes with relatively large current densities and field strengths at the electrode-stem interface. Steady currents on the order of those used in TDDS have been observed to modify the distribution of plant growth hormones, to produce wounding at electrode sites, and to cause stem collapse. This paper presents the preliminary results of an investigation into the effects of the application of voltage steps on the observed dielectric spectrum of the stem of the plant Coleus.
COUNTERION CONDENSATION ON IONIC OLIGOMERS

Abstract The Ramanathan-Woodbury formulas representing the charge density critical for the onset of counterion condensation on finite-length polymers are derived by three alternate methods, an extension of Debye-Huckel theory, a theory of end effects, and by density functional theory. For charged oligomers with length of the same order as the Debye length, the threshold for condensation is the same as for polymers of length much greater than the Debye lenght. However, the threshold depends both on length and salt concentration if the oligomer is shorter than the Debye length, in such a way as to recede to infinity as the ratio of oligomer length to Debye length tends to zero (i.e., condensation vanishes in this limit). The extended Debye-Huckel theory additionally provides a new result for the partition function of the condensed layer, showing that the free energy of the condensed counterions is different on an oligomer and a polymer, even when the fractional extent of condensation is the same. The end effect theory discloses a hitherto unnoticed connection between the number of counterions condensed at the ends of a long polymer and the number condensed on a short oligomer.
Heat shock response in a cellular slime mold, Polysphondylium pallidum.

Abstract Cells of Polysphondylium pallidum were exposed to a heat shock by raising the temperature from 25 to 31°C. A set of four major polypeptides of approximate molecular weights 105,000, 87,000, 74,000, and 33,000 incorporated [1-14C]acetate when pulse labeled during the first hour after heat shock. The response resembles the heat shock response of Drosophila in occurring in cells at different stages of development (early in aggregation, late in aggregation, and during microcyst formation) and in being triggered by a threshold high temperature rather than a minimal change in temperature.
Analytical solutions to constrained hypersonic flight trajectories

The flight trajectory of aerospace vehicles subject to a class of path constraints is considered. The constrained dynamics is shown to be a natural two-time-scale system. Asymptotic analytical solutions are obtained. Problems of trajectory optimization and guidance can be dramatically simplified with these solutions. Applications in trajectory design for an aerospace plane strongly support the theoretical development.
DIFFERENTIAL BLOOD COUNTS IN CERTAIN ADRENAL CORTICAL DISORDERS (CUSHING'S SYNDROME, ADDISON'S DISEASE AND PANHYPOPITUITARISM)

SELYE (10) and Dougherty and White (3) demonstrated in rats that the administration of pituitary adrenocorticotrophic hormone results in an increase in the absolute number of neutrophiles and a decrease in the absolute number of lymphocytes in the blood stream. Dougherty and White (3) obtained the same hematological alterations directly with corticosterone and with 11-dehydro, 17-hydroxycorticosterone (Compound E of Kendall), both of which are adrenal cortical compounds with a marked effect on carbohydrate metabolism, hence “sugar-hormones”. Albright (1) has assembled the evidence that Cushing's syndrome is a manifestation of an hyperadrenocorticism-with-respect-to-the-“sugar-hormone”. It seemed of interest, therefore, to determine whether a neutrophilic leukocytosis coupled with a lymphopenia occurs in patients with this disorder, and to compare the findings with those in primary panhypoadrenocorticism (Addison's disease) and in panhypoadrenocorticism secondary to panhypopituitarism (Simmonds' disease, p...
A Biweight Approach to the One-Sample Problem

Abstract A “t”-like statistic, replacing the classical mean by a biweight location estimator in the numerator and the sample variance by a corresponding variance term in the denominator, is proposed as a modification to that used by Gross (1976) and is evaluated for its efficiency in constructing confidence intervals in symmetric, stretched-tailed situations. The one-sample biweight “t” is shown, via Monte Carlo simulations, to be efficient for samples of moderate sizes (in terms of expected length of the confidence intervals). For smaller samples (size five), the sum of the biweight weights is useful in rescaling biweight “t”. For several samples of common population width, a root mean square of the variances affords greater stability when the underlying distribution is not extremely stretched-tailed.
The impact of the Internet on information seeking in the Media1

There is very little qualitative data on what impact the Internet is having on information seeking in the workplace. Using open‐ended interviews, questionnaires and observation, the impact of the Internet on the British Media was assessed. The focus was largely on newspapers, with The Guardian being covered in some depth. Over 300 journalists and media librarians were surveyed. It was found that amongst traditional journalists use was light. Poor access to the Internet – and good access to other information resources – were largely the reasons for this. Of the journalists it was mainly the older and more senior journalists and the New Media journalists who used the Internet. Librarians were also significant users. Searching the World Wide Web was the principal Internet activity and use was generally conservative in character. Newspapers and official sites were favoured, and searches were mainly of a fact‐checking nature. Email was used on a very limited scale and was not regarded as a serious journalistic tool. Non‐users were partly put off by the Internet‘s potential for overloading them with information and its reputation for producing information of suspect quality. Users generally dismissed these concerns, dealing with potential overload and quality problems largely by using authoritative sites and exploiting the lower quality data where it was needed. Where the Internet has been used it has not been at the expense of other information sources or communication channels, but online hosts seem to be at most risk in the future.
Improving the Trustworthiness of Medical Device Software with Formal Verification Methods

Wearable and implantable medical devices are commonly used for diagnosing, monitoring, and treating various medical conditions. Increasingly complex software and wireless connectivity have enabled great improvements in the quality of care and convenience for users of such devices. However, an unfortunate side-effect of these trends has been the emergence of security concerns. In this letter, we propose the use of formal verification techniques to verify temporal safety properties and improve the trustworthiness of medical device software. We demonstrate how to bridge the gap between traditional formal verification and the needs of medical device software. We apply the proposed approach to cardiac pacemaker software and demonstrate its ability to detect a range of software vulnerabilities that compromise security and safety.
Measuring water collection times in Kenyan informal settlements

This paper uses GPS loggers and interviews to measure the time taken to collect water in two Kenyan informal settlements. The time devoted to water collection is widely believed to prevent women and girls, who do most of this work, from undertaking more creative tasks, including income generation and education. We studied collection times in two settlements to compare Nyalenda in Kisumu, where the utility has introduced a new piped water system, with Kibera in Nairobi, where no such improvement has been made. In addition to the primary results of quantitative collections times, we discuss the use of GPS in this context and our findings that the two methods of measurement provide insights which neither would have provided alone.
Effects of Wheat Starch and Gluten on Tortilla Texture

ABSTRACT Wheat starches were isolated from three wheat flours. Two vital wheat glutens, one from a commercial source and another one isolated from straight-grade flour, were combined with wheat starches to form reconstituted flours with a protein level of 10%. Several characteristics of tortillas made with the hot-press method were measured. No significant difference (P < 0.05) occurred in texture of tortillas made with hard wheat gluten and soft wheat gluten. Wheat starches did not have any significant (P < 0.05) effect on tortilla stretchability or foldability. Analysis of variance confirmed that wheat starch and gluten had limited effects on tortilla texture. The possible reasons were that the solubles of wheat flour were not included, and the shortening in the tortilla formula interfered with the interaction of gluten and starch.
Water consumption of rats with septal lesions following two days of water deprivation

Abstract Rats with bilateral septal lesions consumed more water than operated control animals under ad libitum conditions. Following 48 hr of water deprivation these differences were increased and animals with septal lesions took longer to return to pre-deprivation levels of consumption than operated controls. It was further suggested that the lightest weight animals drank the most water regardless of group, but that the greatest difference between groups was seen in those lightest weight animals.
Complexity analysis of oligodendroglial processes expressing myelin‐associated glycoprotein

Oligodendroglia synthesize myelin in the mammalian central nervous system. Mature oligodendroglia have been identified in culture by two criteria; the expression of molecules characteristic of myelin, such as galactocerebroside (galC) and myelin-associated glycoprotein (MAG), and the elaboration of complex processes. Myelin gene expression can be documented by the binding of specific antibodies and antisera to the myelin-specific molecules; process complexity can be described by the fractal dimension, D. In this study, anti-MAG antisera was used to document MAG expression in the processes of oligodendroglia. Eighty percent of the galC+ oligodendroglia bound anti-MAG antiserum. With time in culture, MAG immunoreactivity seemed to extend from the cell soma into the oligodendroglial processes. To quantify this observation, fractal dimensions were calculated using either galC or MAG immunoreactivity to visualize oligodendroglial processes. A fractal dimension of 1.5 was calculated for O1+ processes by day 4 of culture; this value for D remained constant over the course of 1 month in culture. The fractal dimension calculated for MAG+ processes increased from 1.2 to 1.5 over the course of 28 days in culture. This change in fractal dimension confirms our visual impression that galC-containing processes acquire MAG slowly over the course of several weeks in culture.
Human histamine N-methyltransferase pharmacogenetics: gene resequencing, promoter characterization, and functional studies of a common 5'-flanking region single nucleotide polymorphism (SNP).

Abstract Histamine N-methyltransferase (HNMT) catalyzes one of two major metabolic pathways for histamine. The levels of HNMT activity and immunoreactive protein in human tissues are regulated primarily by inheritance. Previous studies of HNMT identified two common single nucleotide polymorphisms (SNPs), including a functionally significant nonsynonymous coding SNP (cSNP), (C314T, Thr105Ile), but that polymorphism did not explain all of the phenotypic variation. In the present study, a genotype-to-phenotype strategy was used to search for additional genetic factors that might contribute to the regulation of human HNMT activity. Specifically, we began by resequencing the human HNMT gene using 90 ethnically anonymous DNA samples from the Coriell Cell Repository and identified a total of eight SNPs, including the two that had been reported previously. No new nonsynonymous cSNPs were observed, but three of the six novel SNPs were located in the 5′-flanking region (5′-FR) of the gene—including a third common polymorphism with a frequency of 0.367 (36.7%). That observation directed our attention to possible genetic effects on HNMT transcription. As a first step in testing that possibility, we created and studied a series of reporter gene constructs for the initial 1 kb of the HNMT 5′-FR. The core promoter and possible regulatory regions were identified and verified by electrophoresis mobility shift assays. We then studied the possible functional implications of the new common HNMT 5′-FR SNP. However, on the basis of reporter gene studies, that SNP appeared to have little effect on transcription. Phenotype–genotype correlation analysis performed with 112 human kidney biopsy samples that had been phenotyped for their level of HNMT activity confirmed that the common 5′-FR SNP was not associated with the level of HNMT activity in vivo. In summary, this series of experiments resulted in the identification of several novel HNMT polymorphisms, identification of the HNMT core promoter, and a comprehensive functional genomic study of a common HNMT 5′-FR SNP. These results represent an additional step in the definition of molecular genetic mechanisms involved in the regulation of this important autacoid-metabolizing enzyme in humans.
On the longest circuit in an alterable digraph

Analterable digraph is a digraph with a subset of its edges marked alterable and their orientations left undecided. We say that an alterable digraph has an invariant ofk on the length of the longest circuit if it has a circuit of length at leastk regardless of the orientations over its alterable edges. Computing the maximum invariant on the length of the longest circuit in an alterable digraph is aglobal optimization problem. We show that it is hard to approximate the global optimal solution for the maximum invariant problem.
Functional Calcium-sensing Receptors in Rat Fibroblasts Are Required for Activation of SRC Kinase and Mitogen-activated Protein Kinase in Response to Extracellular Calcium

Changes in the concentration of extracellular calcium can affect the balance between proliferation and differentiation in several cell types, including keratinocytes, breast epithelial cells, and fibroblasts. This report demonstrates that elevation of extracellular calcium stimulates proliferation-associated signaling pathways in rat fibroblasts and implicates calcium-sensing receptors (CaR) as mediators of this response. Rat-1 fibroblasts express CaR mRNA and protein and respond to known agonists of the CaR with increased IP3 production and release of intracellular calcium. Agonists of the CaR can stimulate increased c-SRC kinase activity and increased extracellular signal-regulated kinase 1/mitogen-activated protein kinase activity. Both of the increases in SRC activity and mitogen-activated protein kinase activation are blocked in the presence of a nonfunctional mutant of the CaR, R796W. Proliferation of wild-type Rat-1 cells is sensitive to changes in extracellular calcium, but expression of the nonfunctional CaR mutant or inhibition of the calcium-dependent increase in SRC kinase activity block the proliferative response to calcium. These results provide evidence of a novel signal transduction pathway modulating the response of fibroblasts to extracellular calcium and imply that calcium-sensing receptors may play a role in regulating cell growth in response to extracellular calcium, in addition to their well known function in systemic calcium homeostasis.
Bipolar Illness, God, and Object Relations: The Treatment of M

This article explores the concomitant change in one client's object relations and his image of God that occurred in the context of psychoanalytically oriented psychotherapy. The case demonstrates the benefit of long-term psychoanalytically oriented treatment to help an individual with major mental illness to heal emotionally, mentally, and spiritually. The client, who suffers from bipolar I disorder, experienced significant developmental mastery as he moved from the paranoid/schizoid position to the depressive position (developmental stages conceptualized by theorists Melanie Klein and Douglas Fairbairn). In addition, the psychotherapy mitigated the effects of homonegativity on M's self-image and his experience of his homosexuality. Through our work, the client began to see and interact with this clinical social worker, others, and the God of his understanding, in a more realistic and healthy manner. M's participation in a 12-Step group and his adherence to its beliefs augmented changes he made through ps...
A direct ab initio dynamics study of the water‐assisted tautomerization of formamide

Direct ab initio dynamics calculations based on a canonical variational transition-state theory with several multidimensional semiclassical tunneling approximations were carried out to obtain rate constants for the water-assisted tautomerization of formamide. The accuracy of the density functionals, namely, B-LYP, B3-LYP, and BH&H-LYP, were examined. We found that the BH&H-LYP method yields the most accurate transition-state properties when comparing it to ab initio MP2 and QCISD results, whereas B-LYP and B3-LYP methods predict barrier heights too low. Reaction path information was calculated at both the MP2 and nonlocal hybrid BH&H-
A prospective study of histocompatible leukocyte and platelet transfusions during induction chemotherapy of adult acute nonlymphocytic leukemia

A prospective clinical trial was conducted to test the effectiveness of granulocyte transfusions during induction chemotherapy of patients with adult acute non-lymphocyte leukemia. Thirty-eight patients who received prophylactic granulocyte transfusions from related donors when their phagocyte counts decreased to less than 1000 microliter were compared to twenty-five controls who did not have qualified donors from which to obtain granulocyte transfusions. The frequency of complete remissions (CR) (28/38 versus 7/25) was significantly greater for the granulocyte transfusion group than for controls. Patients older than 45 responded more often in the transfused group (P less than 0.025) when compared to the similar age group in controls. Both duration of complete remission and survival were greater in the granulocyte transfused group. However, these differences were not statistically significant. Survival for all responders (complete plus partial remission) was longer for the granulocyte transfusion group (P = 0.01). No significant difference in frequency or severity of either infection or hemorrhage was noted in the two groups. The advantage noted in this study largely occurred in patients older than 45 and this suggests that this age group is more likely to respond if they have histocompatible donors from which to obtain granulocyte and platelet transfusions. Immune mechanisms may be involved in the beneficial effects observed with HLA compatible granulocyte transfusions.
AGU's Thriving Earth Exchange: Five Reasons to Join In

AGU has launched the Thriving Earth Exchange, a new initiative that supports communities as they protect themselves from hazards, adapt to a changing planet, and create sustainable futures. Through the program, AGU members will work with local leaders to contribute their Earth and space science expertise to these significant societal challenges.
Models of the cerebellum and motor learning

This article reviews models of the cerebellum and motor learning, from the landmark papers by Marr and Albus through those of the present time. The unique architecture of the cerebellar cortex is ideally suited for pattern recognition, but how is pattern recognition incorporated into motor control and learning systems? The present analysis begins with a discussion of exactly what the cerebellar cortex needs to regulate through its anatomically defined projections to premotor networks. Next, we examine various models showing how the microcircuitry in the cerebellar cortex could be used to achieve its regulatory functions. Having thus defined what it is that Purkinje cells in the cerebellar cortex must learn, we then evaluate theories of motor learning. We examine current models of synaptic plasticity, credit assignment, and the generation of training information, indicating how they could function cooperatively to guide the processes of motor learning.
Structure and Function of the Influenza A M2 Proton Channel

The M2 protein of influenza A viruses forms a tetrameric pH-activated proton-selective channel that is targeted by the amantadine class of antiviral drugs. Its ion channel function has been extensively studied by electrophysiology and mutagenesis; however, the molecular mechanism of proton transport is still elusive, and the mechanism of inhibition by amantadine is controversial. We review the functional data on proton channel activity, molecular dynamics simulations of the proton conduction mechanism, and high-resolution structural and dynamical information of this membrane protein in lipid bilayers and lipid-mimetic detergents. These studies indicate that elucidation of the structural basis of M2 channel activity and inhibition requires thorough examination of the complex dynamics and conformational plasticity of the protein in different lipid bilayers and lipid-mimetic environments.
Sugar pills for pancreatic cancer: the benefits of becoming (insulin) sensitive.

Background & Aims: Our previous study suggested that the known promotional effect of a high fat diet, which in hamsters induces peripheral insulin resistance, is related to a compensatory proliferation of islet cells. The present study was to examine whether the prevention of islet cell proliferation can inhibit the promotional effect of a high-fat diet in pancreatic carcinogenesis. Methods: Two groups of high fat-fed hamsters were used. One group received Metformin in drinking water for life (HF+Met group), and the other group served as a control (HF group). At the time when the normalization of the plasma insulin level was expected, all hamsters were treated with the pancreatic carcinogen, N-nitrosobis-(2-oxopropyl)amine, and the experiment was terminated 42 weeks later. Results: Although 50% of the hamsters in the high-fat group developed malignant lesions, none was found in the HF+Met group (P < 0.05). Also, significantly more hyperplastic and premalignant lesions, most of which were found within the islets, were detected in the high-fat group (8.6 lesions/hamster) than in the HF+Met group (1.8 lesions/hamster). Conclusions: The results lend further support on the significant role of islet cells in pancreatic carcinogenesis and may explain the association between pancreatic cancer and obesity, which is usually associated with peripheral insulin resistance.
LOCKE ON IDEAS OF SUBSTANCE AND THE VEIL OF PERCEPTION

John Yolton has argued that Locke held a direct realist position according to which sensory ideas are not perceived intermediaries, as on the representational realist position, but acts that take material substances as objects. This paper argues that were Locke to accept the position Yolton attributes to him he could not at once account for appearance-reality discrepancies and maintain one of his most important anti-nativist arguments. The paper goes on to offer an interpretation of Locke's distinction between ideas of substances and modes, a distinction that helps Locke to explain appearance-reality discrepancies, although not in a large enough range of cases to strengthen Yolton's interpretation.
Muscles in a mouse model of spinal muscular atrophy show profound defects in neuromuscular development even in the absence of failure in neuromuscular transmission or loss of motor neurons

A mouse model of the devastating human disease "spinal muscular atrophy" (SMA) was used to investigate the severe muscle weakness and spasticity that precede the death of these animals near the end of the 2nd postnatal week. Counts of motor units to the soleus muscle as well as of axons in the soleus muscle nerve showed no loss of motor neurons. Similarly, neither immunostaining of neuromuscular junctions nor the measurement of the tension generated by nerve stimulation gave evidence of any significant impairment in neuromuscular transmission, even when animals were maintained up to 5days longer via a supplementary diet. However, the muscles were clearly weaker, generating less than half their normal tension. Weakness in 3 muscles examined in the study appears due to a severe but uniform reduction in muscle fiber size. The size reduction results from a failure of muscle fibers to grow during early postnatal development and, in soleus, to a reduction in number of fibers generated. Neuromuscular development is severely delayed in these mutant animals: expression of myosin heavy chain isoforms, the elimination of polyneuronal innervation, the maturation in the shape of the AChR plaque, the arrival of SCs at the junctions and their coverage of the nerve terminal, the development of junctional folds. Thus, if SMA in this particular mouse is a disease of motor neurons, it can act in a manner that does not result in their death or disconnection from their targets but nonetheless alters many aspects of neuromuscular development.
Education and the changing age pattern of American fertility: 1963-1989

Using pooled data from the 1980, 1985, and 1990 Current Population Surveys, we describe fertility trends by age and education for the period 1963-1989. Interest focuses on whether the effects of education have changed across this period. We show that women with college degrees experienced dramatic shifts toward later ages of childbearing. This shift is consistent with arguments we develop about the increased opportunity for women to pursue careers and about changes in the availability of child care.
Neonatal outcome of triplet versus twin and singleton pregnancies: a matched case control study

Objective: To determine the neonatal outcome of triplet gestations versus that of singletons and twins matched for gestational age. Study design: All live born triplet gestations delivered between 1 April 1993 and 31 March 2000 were compared to an age matched control group consisting of live born twins and singletons. The neonatal outcome of 116 sets of triplets was compared to that of 116 sets of twins and 116 singletons. Results: During a 7-year period 116 sets of triplet pregnancies were reviewed. Of 116 sets of live born triplets (348 newborns), 70.67% triplets were born between 33- and 36-week gestation, 28.44% between 28 and 32 weeks and 0.86% less than 28 weeks. Triplets were smaller in weight than singletons but not twins. Apgar score, use of prenatal steroid and sex ratio were similar in the three groups. Incidence of respiratory distress syndrome (RDS), use of surfactant, infants requiring intubation, pneumothorax, patent ductus arteriosus, sepsis, intraventricular hemorrhage, periventricular leucomalacia, retinopathy of prematurity, necrotizing enterocolitis, gastroesophageal reflux and jaundice requiring phototherapy were not statistically different among the three groups. Incidence of major and minor congenital anomalies, percent neonatal intensive care unit (NICU) admissions, and mean duration of NICU stay were also similar. There was no influence of birth order on neonatal outcome of triplet pregnancy and outcome did not significantly change over 7 years of the study period. Conclusions: Triplets have a similar outcome to twins and singletons when matched for gestational age. Since outcome is dependent on gestational age, the closer the gestational age is to term the better is the outcome.
Thiol Level in Liver, Kidneys and Blood of Chickens Resistant and Susceptible to Lymphoid Leukosis or Marek’s Disease,

Abstract Total, soluble and protein bound thiol values of the livers and kidneys and the soluble blood thiol values were determined using 10 strains of chickens selected for resistance or susceptibility to lymphoid leukosis and/or Marek’s disease. Liver total thiol, and liver soluble thiol were higher (P
THROMBOXANE B2 INHIBITS THE PULMONARY INACTIVATION OF PROSTAGLANDIN E2 IN THE DOG

Abstract 1 The systemic vasodepressor response to intravenously administered prostaglandin E2 (PGE2, 0.3, 1.0 and 3.0 micrograms/kg) is potentiated during intravenous infusion of thromboxane B2 (TXB2, 1.0 micrograms kg-1 min-1) in the anaesthetized dog. 2 The augmented haemodynamic response returns toward control values following cessation of the TXB2 infusion. 3 The systemic haemodynamic responses to intra-arterially administered PGE2, PGF2 alpha and PGI2 as well as intravenously administered PGF2 alpha and PGI2 are not altered by TXB2 infusion. 4. This study suggests that TXB2 inhibits the pulmonary inactivation of PGE2. 5 Arachidonic acid metabolites may interact, producing haemodynamic responses differing from their individual effects.
SU-E-T-563: A Fast and Quantative Picket-Fence Test of a Submillimeter Patient Positioning System for Stereotactic Radiosurgery

Purpose: Picket-fence test is a qualitative TG142-recommended quality assurance (QA) test for multileaf collimators. In study, we adopted the same concept and developed a fast but quantatitive QA test for an automatic patient positioning system that requires submilleter accuracy for a radiosurgical treatment. Methods: A piece of radiochromic film was first placed inside a spherical solid water phantom and then irradiated with a sequenence of linearly placed shots of same collimator size (e.g. 4-mm) via the Leskell Gamma Knife Perfexion system (PFX). The shots were positioned with either equal or non-equal gaps of approximately 4 mm to 8 mm depending on the location of the region of interest. A pattern recognization program was developed and then applied to measure the gap spacing between two adjacent shots. The measured distance was then compared with the initial preset values for the test. Results: By introducing variable systematic and random shifts of 0.1 mm to 0.5 mm to the shot sequence, the maximum gap variation from the described test was found to be 0.35 mm or less. On average the positioning uncertainty for the PFX delivery system was found to be 0.1±0.2 mm. No significant difference in the positioning uncertainty was noted for the centrally aligned shot sequence locations versus the peripherally aligned shot sequence locations. Conclusion: A new quantitative picket-fence type test was developed and demonstrated for routine QA of the submillimeter PFX patient positioning sytem. This test also enables independent verification of any patient-specific shot positioning for a critical treatment such as a tumor in brainstem. Dr Ma is currently on the board of international society of stereotactic Radiosurgery
A Multiple-Component Analysis of US Dairy Trade

This paper develops a multiple component-based methodology to account for imports and exports of dairy products and products with a significant dairy content. More specifically, it accounts for imports, exports, and net trade for all dairy products on the basis of milk fat, protein, other solids, and moisture. This approach provides a less biased method of assessing the amount of dairy imports entering the US than the USDA's milk equivalent conversions.
Practical aspects of ADCP data use for quantification of mean river flow characteristics; Part I: moving-vessel measurements

Abstract Acoustic Doppler Current Profiler (ADCP) measurements have gained considerable popularity because of their capabilities to efficiently measure discharges from boats moving across river transects. The accuracy of the estimated discharges is relatively good compared with the existing measurement alternatives. Currently, there is an increased demand for measurement of the mean velocity field in rivers for applications where mean and turbulence quantities play important roles. Given the good estimates for discharges, it can be inferred that velocity profiles collected during transects can be potentially used for characterization of the average mean velocity field. Instrument and operational limitations, as well as environmental factors result in large scattering of the instantaneous velocity profiles collected from moving boats during transects, making it difficult to readily use the collected data for reporting mean velocities and turbulence parameters across the depth or in cross-sections. The paper presents several methods for enhancing the significance of the ADCP velocity distribution profiles collected from moving boats and proposes complementary software to further process and visualize the ADCP data for better support of hydraulic investigation requirements. The paper analyzes first the assumptions and error sources involved in the measurement process. The appearance of the velocity profiles collected with ADCP operated from moving vessels and post-processing algorithms for data conditioning and smoothing are tested and evaluated next. The relevance of data collected from moving vessels along transects for description of the mean velocity profiles is inferred by comparison with data obtained with the same ADCP system and settings, collected from fixed locations along the transect route. Velocities enhanced using the optimum tested post-processing algorithms are used to further determine depth-averaged velocities, velocity components in river coordinates, and river discharge estimates.
Phytoremediation of High-Phosphorus Soil by Annual Ryegrass and Common Bermudagrass Harvest

Removal of soil phosphorus (P) in crop harvest is a remediation option for soils high in P. This 4-year field-plot study determined P uptake by annual ryegrass (ARG, Lolium multiflorum Lam.) and common bermudagrass (CB, Cynodon dactylon (L.) Pers.) from Ruston soil (fine-loamy, siliceous, thermic Typic Paleudult) enriched in P by five previous annual applications of poultry litter, and related P removed to Bray 2 P in surface (0–15 cm) soil. Decreases in surface soil Bray 2 P were largely attributable to uptake. Phosphorus uptake was positively related to Bray 2 P but approached a limit. Mass of P removed in harvest closely approximated the decrease in mass of surface soil Bray 2 P. Maximum Bray 2 P drawdown per harvest (ARG and CB, average) was ˜3 mg kg−1 at Bray 2 P ˜ 300 mg kg−1, generally consistent with measured decreases in Bray 2 P.
A review of Charcot neuroarthropathy of the midfoot and hindfoot: what every radiologist needs to know

Charcot neuroarthropathy (CN) occurs commonly in diabetic patients in the joints of the foot and ankle. Radiologists may be the first to suggest the diagnosis of CN and can facilitate prompt intervention and treatment if they are aware of the radiographic manifestations of CN and the signs of progression of disease. Radiologists should also become aware of the evolving treatment of the disease as focus is shifting toward early surgical intervention and limb salvage rather than amputation. Knowledge of preoperative assessment, the types of surgeries performed, and some of the encountered postoperative complications enable the radiologist to facilitate timely intervention by our surgical colleagues and be a valuable member of the management team.
Deleterious activity of cultivated grasses (Poaceae) and residues on soilborne fungal, nematode and weed pests

Experiments were conducted in laboratory bioreactors and in field plots to test effects of certain cultivated members of the grass family (Poaceae = Gramineae), including wheat (Triticum aestivum cv. Yolo), barley (Hordeum vulgare cv. UC337), oats (Avena sativa cv. Montezuma), triticale (X Triticosecale), and a sorghum-sudangrass hybrid (Sorghum bicolor x S. sudanense = “sudex”, cv. Green Grazer V) for soil disinfestation potential. Soilborne pest organisms tested for effects on survival and activity included the phytopathogens Sclerotium rolfsii, Pythium ultimum and Meloidogyne incognita, and a variety of weed taxa. Following soil amendment, bioreactors were incubated for 7 days at ambient (23°C) or elevated, but sublethal (38°C day/27°C night), soil heating regimens. Addition of each of the poaceous amendments to soil at 23°C resulted in inconsistently reduced tomato root galling (49–97%) by M. incognita, or reduced recovery of S. rolfsii and P. ultimum (0–100%) fungi in soil, after 7 days’ incubation (P ≤ 0.05). When the organisms were exposed to the poaceous soil amendments at the 38o/27o temperature regimen, nematode galling and recovery of active fungi were consistently and significantly reduced by 98–100%. These results demonstrated feasibility of soil disinfestation (“biofumigation”) by activity of poaceous amendments, further aided by combining plant residues with soil heating (e.g. solarization). Results from three field experiments with sudex cover crops, conducted throughout the growing season, demonstrated biocidal activity on a range of weedy plants, including Amaranthus retroflexus, Calandrinia ciliata, Cerastium arvense, Digitaria sanguinalis, Echinochloa crus-galli and Poa annua. Both shoots and roots of sudex provided allelopathic weed biomass reductions of 35–100%, and for at least 106 days after shredding. Deleterious activity of shredded residues incorporated in soil was less persistent. These properties in poaceous crops can be useful for soil disinfestation; however, harmful phytotoxicity to subsequent crops may also result. In order to take full advantage of these low-input measures for controlling soilborne diseases and pests, further understanding of their properties must be gained, and user guidelines developed.
On the construction of geomagnetic timescales from non-prejudicial treatment of magnetic anomaly data from multiple ridges

SUMMARY When marine magnetic-anomaly data are used to construct geomagnetic polarity timescales, the usual assumption of a smooth spreading-rate function at one seafloor spreading ridge forces much more erratic rate functions at other ridges. To eliminate this problem, we propose a formalism for the timescale problem that penalizes non-smooth spreading behaviour equally for all ridges. Specifically, we establish a non-linear Lagrange multiplier optimization problem for finding the timescale that (1) agrees with known chron ages and with anomaly-interval distance data from multiple ridges and (2) allows the rate functions for each ridge to be as nearly constant as possible, according to a cumulative penalty function. The method is applied to a synthetic data set reconstructed from the timescale and rate functions for seven ridges, derived by Cande & Kent (1992) under the assumption of smooth spreading in the South Atlantic. We find that only modest changes in the timescale (less than 5 per cent for each reversal) are needed if no one ridge is singled out for the preferential assumption of smoothness. Future implementation of this non-prejudicial treatment of spreading-rate data from multiple ridges to large anomaly-distance data sets should lead to the next incremental improvement to the pre-Quaternary geomagnetic polarity timescale, as well as allow a more accurate assessment of global and local changes in seafloor spreading rates over time.
Protein–Protein Interactions Governing Septin Heteropentamer Assembly and Septin Filament Organization in Saccharomyces cerevisiae

Mitotic yeast (Saccharomyces cerevisiae) cells express five related septins (Cdc3, Cdc10, Cdc11, Cdc12, and Shs1) that form a cortical filamentous collar at the mother-bud neck necessary for normal morphogenesis and cytokinesis. All five possess an N-terminal GTPase domain and, except for Cdc10, a C-terminal extension (CTE) containing a predicted coiled coil. Here, we show that the CTEs of Cdc3 and Cdc12 are essential for their association and for the function of both septins in vivo. Cdc10 interacts with a Cdc3–Cdc12 complex independently of the CTE of either protein. In contrast to Cdc3 and Cdc12, the Cdc11 CTE, which recruits the nonessential septin Shs1, is dispensable for its function in vivo. In addition, Cdc11 forms a stoichiometric complex with Cdc12, independent of its CTE. Reconstitution of various multiseptin complexes and electron microscopic analysis reveal that Cdc3, Cdc11, and Cdc12 are all necessary and sufficient for septin filament formation, and presence of Cdc10 causes filament pairing. These data provide novel insights about the connectivity among the five individual septins in functional septin heteropentamers and the organization of septin filaments.
An analytical method for design of compliant grippers with macro/micro manipulation and assembly applications

A compliant gripper gains its dextral manipulation by the flexural motion of its fingers. It is a preferable device to grippers with actuations because of reduced fabrication complexity and increased structural reliability. The prediction of contact forces and deflected shape are essential to the design of a compliant gripper. We present here a formulation based on nonlinear constrained optimization (NCO) techniques to analyze contact problems of compliant grippers. For a planar compliant gripper this formulation essentially reduces the domain of discretization by one dimension. Hence it requires simpler formulation and is computationally more efficient than other methods such as finite element analysis. As this method is rather generic, its use would facilitate design analysis and optimization of compliant devices. We illustrate these attractive features with two types of compliant grippers; macro-handling and micro-assembly applications
AIDS and Community Health Issues.

“Toxoplasmic Encephalitis in Patients with Acquired Immune Deficiency Syndrome,” Benjamin J. Luft, et al. An epidemic of cases of toxoplasmic encephalitis is occurring in patients with acquired immune deficiency syndrome (AIDS). Serological or histopathologic studies were performed on 70 cases with AIDS and toxoplasmic encephalitis. In many cases conventional stains of brain-tissue specimens failed to disclose Toxoplasma organisms; all were positive when stained by the peroxidase-antiperoxidase technique. Except for a single patient, serological titers were not indicative of an acute acquired infection. The ratios of titers in the agglutination test to titers in the Sabin-Feldman dye test seemed to be more predictive of active toxoplasmic encephalitis in patients with AIDS than either test alone. Based on histological and serological data, an approach is presented for diagnosis and treatment of suspected toxoplasmic encephalitis in patients with AIDS. (Journal of the American Medical Association ...
Perceived influence of close friends, well-liked peers, and popular peers: Reputational or personal influence?

This study examined two types of influence (reputational and personal) children perceive from different sources (i.e., close friends, well-liked peers, and popular peers). Participants included 455 third through fifth grade students. A quadratic assignment procedure was used wherein children’s peer nominations of the source of influence were correlated with their nominations of the type of influence. Findings suggested that children perceive personal influence more so than reputational influence from close friends and well-liked peers. In contrast, children perceive reputational influence more so than personal influence from popular peers. The degree to which children perceive personal influence from the three sources differed by behavioral domains (i.e., academic and trend-following behaviors). Implications for peer influence research and intervention are discussed.
Maturation of Little Skate and Winter Skate in the Western Atlantic from Cape Hatteras to Georges Bank

Abstract We estimated the length and age of maturation in little skate Leucoraja erinacea and winter skate L. ocellata based on samples of 1,884 little skate and 1,153 winter skate ovaries collected from Cape Hatteras, North Carolina, to Georges Bank. Two levels of maturity were recognized: onset maturity, which marks the onset of the allocation of energy from somatic growth to reproduction; and “functional” maturity, which marks the point when mature oocytes are released. Size at maturation increased with latitude in little skate, 50% onset maturity occurring at 42.5, 43.0, and 46.5 cm (total length) and 50% functional maturity at 43, 44, and 46 cm for the mid-Atlantic, southern New England–Georges Bank, and Gulf of Maine regions, respectively. Based on age estimates from previously published work, the age at which little skate achieve functional maturation ranged between 7.0 and 7.5 years for the U.S. northeast coast. In winter skate, no statistically significant regional differences in maturation rates...
Polymer-capped fiber-optic Raman probe for non-invasive Raman spectroscopy.

Advances in fiber optic probe design are moving Raman spectroscopy into the clinic, although there remain important practical problems. While much effort has been devoted to minimizing Raman and fluorescence background from fibers, less attention has been given to the need to generate reference Raman signals that can correct for variations in tissue albedo, which is important in quantifying changes in tissue composition. To address this shortcoming, we have developed a fiber optic probe that incorporates a fluorinated ethylene-propylene copolymer (FEP) cap at the end of each excitation fiber. Transmission of laser light through the transparent cap generates a 732 cm−1 Raman band whose intensity scales linearly with the laser power delivered to the tissue of interest. In our first design, the FEP cap functions as a waveguide with only a small insertion loss (∼5%). Laser transmission through 1 mm of the polymer is sufficient to generate a usable reference Raman signal. We show the application of the probe to quantitative non-invasive Raman spectroscopy of animal tissues using rat leg phantoms as models. Ex-vivo Raman spectroscopy of excised rat tibia supports the use of the probe for spectroscopy of various tissues. These results provide proof of principle that the Raman probe can be used in multiple spectroscopic applications.