cssi/SciSciGPT-SciSciNet huggingface dataset:
The chemistry and biology of oligonucleotide conjugates.

Short DNA or RNA oligonucleotides have tremendous potential as therapeutic agents. Because of their ability to engage in Watson–Crick base pairing, they can interact with mRNA or pre-mRNA targets with high selectivity. As a result, they could precisely manipulate gene expression. This possibility has engendered extensive efforts to develop oligonucleotides as drugs, and many candidates are already in clinical trials. However, a major impediment to the maturation of this field of oligonucleotide-based therapeutics remains: these relatively large and often highly charged molecules don’t easily cross cellular membranes, making it difficult for them to reach their sites of action in the cytosol or nucleus.In this Account, we summarize some basic features of the biology of antisense and siRNA oligonucleotides. We then discuss chemical conjugation as an approach to improving the intracellular delivery and therapeutic potential of these agents. Instead of focusing on the details of conjugation chemistry, we emph...
Powerful Portfolios for Young Children

The use of portfolio assessment is a valuable tool for teachers to use with young children to better understand how young children develop and learn. An intentional data collection and documentation system becomes a very powerful assessment tool, one that is authentic and based on children’s capabilities and strengths. Children, educators, parents, and administrators are able to see the collection of items that celebrates the child. This article will describe several aspects of the portfolio system including: what a portfolio is; it’s purposes; how to create the portfolio; and, how to use the portfolio with families.
Radiation diagnostics and dosimetry modeling for characterization of plasma-beam interactions and x-ray production for a 500kV MILO

The University of New Mexico Electrical Engineering Department has designed and fabricated a Magnetically Insulated Transmission Line Oscillator (MILO) to operate with a 100 ns to 300 ns pulse capability at 500 kV driven by a marx capacitor bank. Its main purpose is to study the interaction between beams and plasmas as they relate to high power microwave production. The coaxial geometry MILO utilizes the self-generated magnetic insulation derived from high electron currents to maintain power flow. This eliminates the need for externally applied magnetic fields. The device the n utilizes a slow wave structure to couple electron energies in to high power microwaves on the order of 1.1 GHz. The operation of the device also results in the production of ionizing bremsstrahlung radiation due to electrons impinging on the aluminum walls of the device. The number of bremsstrahlung photons, the energy of the bremsstrahlung, and the angular distribution of those photons can be analyzed to effectively postulate the behavior of the beam and plasmas evolving from the cathode and anode. This paper presents the design of a tungsten pinhole camera built to identify time inte grated electron impact and x-ray production resulting from firing the MILO; these data will then be correlated with other diagnostics and particle in cell models to gain understanding of the beam plasma interactions within the vacuum chamber. MCNP radiation transport simulations were used in conjunction with measurements taken from thermo luminescent dosimeters and pin-diode radiation detectors in order to determine the radiation dose rates within the laboratory space housing the MILO. This data was then analyzed and used to properly to design adequate shielding as well as safety procedures within the laboratory to eliminate any risk of exposure to radiation exceeding the dose limits outlined in NRC 10CFR20 and university guidelines.
Single photons on pseudodemand from stored parametric down-conversion

We describe the results of a parametric down-conversion experiment in which the detection of one photon of a pair causes the other photon to be switched into a storage loop. The stored photon can then be switched out of the loop at a later time chosen by the user, providing a single photon for potential use in a variety of quantum information processing applications. Although the stored single photon is only available at periodic time intervals, those times can be chosen to match the cycle time of a quantum computer by using pulsed down-conversion. The potential use of the storage loop as a photonic quantum memory device is also discussed.
Increasing the sensitivity-bandwidth product of resonant FSR optical modulators using coupled resonators

Electro-optical dual-disc (1:2 ratio of diameter), resonant, RF-optical modulators have been analyzed to enhance both the sensitivity and bandwidth compared to a single disc structure when modulating at the FSR.
Gynecologic clostridial toxic shock in women of reproductive age

Clostridial toxic shock, caused by Clostridium sordellii or Clostridium perfringens, is a rare and largely fatal syndrome among reproductive-aged women with genital tract infection, and may occur following various pregnancy outcomes or without pregnancy. Clinicians should be aware of common clinical features of this very rapidly-progressing syndrome including abdominal pain, tachycardia, hypotension, third-space fluid accumulations, hemoconcentration, and marked leukemoid response, often with lack of fever. In this review, we summarize known cases through mid-2011 and information on clinical presentation, diagnosis, treatment, and results of recent investigations regarding pathogenesis, including germination, toxins, and host response that may have important implications for development of preventive or therapeutic interventions.
Effects of acute low-level microwaves on pentobarbital-induced hypothermia depend on exposure orientation

Two series of experiments were performed to study the effects of acute exposure (45 min) to 2,450-MHz circularly polarized, pulsed microwaves (1 mW/cm2, 2-mus pulses, 500 pps, specific absorption rate (SAR) 0.6 W/kg) on the actions of pentobarbital in the rat. In the first experiment, rats were irradiated with microwaves and then immediately injected with pentobarbital. Microwave exposure did not significantly affect the extent of the pentobarbital-induced fall in colonic temperature. However, the rate of recovery from the hypothermia was significantly slower in the microwave-irradiated rats and they also took a significantly longer time to regain their righting reflex. In a second experiment, rats were first anesthetized with pentobarbital and then exposed to microwaves with their heads either pointing toward the source of microwaves (anterior exposure) or pointing away (posterior exposure). Microwave radiation significantly retarded the pentobarbital-induced fall in colonic temperature regardless of the orientation of exposure. However, the recovery from hypothermia was significantly faster in posterior-exposed animals compared to those of the anterior-exposed and sham-irradiated animals. Furthermore, the posterior-exposed rats took a significantly shorter time to regain their righting reflex than both the anterior-exposed and sham-irradiated animals.
Quantitation of proliferative mucosal cells of the Mongolian gerbil on a weight basis.

Quantitation of proliferative activity of the intestine of the gerbil shows a substantial decrease in proliferative activity as compared to the mouse. The use of dry vs wet weights proved to have no bearing on calculations of proliferative activity. The gerbil may prove a useful model for drug and radiation experimentation.
Ethanol inhibition: the humoral and cellular immune response to hepatitis C virus NS5 protein after genetic immunization.

Background: The combination of chronic hepatitis C virus (HCV) and ethanol may increase viral replication, impair cellular immunity, and result in severe and progressive liver disease. Because HCV nonstructural proteins play a major role in viral elimination, we examined the cellular and humoral immune responses after genetic immunization against NS5 in a chronic ethanol mouse model. Methods: Mice were fed an ethanol or isocaloric pair-fed control liquid diet and were immunized with HCV NS5-expression plasmid. Results: The humoral and cellular arms of the immune system were significantly impaired in ethanol-fed mice. Abstinence partially reversed the inhibitory effects on antibody levels and the CD4+ proliferative immune response but did not restore the CD8+ cytotoxic T-cell response to this HCV nonstructural protein. Furthermore, we determined whether murine interleukin-2 coadministration with the NS5 expression plasmid would reverse the inhibitory effects of chronic ethanol consumption; again, partial restoration was observed for B-cell and CD4+ T-cell activity, but not for cytotoxic T cells. Conclusions: These results suggest that the high rate of chronic HCV infection in alcoholics may be due to ethanol's effects on antiviral immune responses.
Counting as a sequence of bernoulli trials

It is shown that a certain estimator, applied in the physical sciences to counts of particles, is in general inconsistent: it need not and, normally, does not converge in probability towards the true value of the estimated number; it converges, however, towards a lower bound of it. By splitting the process of counting into suitable sub-counts, it appears possible to overcome this difficulty.
Specific expression of a tyrosine kinase gene, blk, in B lymphoid cells

Several pathways of transmembrane signaling in lymphocytes involve protein-tyrosine phosphorylation. With the exception of p56lck, a tyrosine kinase specific to T lymphoid cells that associates with the T cell transmembrane proteins CD4 and CD8, the kinases that function in these pathways are unknown. A murine lymphocyte complementary DNA that represents a new member of the src family has now been isolated and characterized. This complementary DNA, termed blk (for B lymphoid kinase), specifies a polypeptide of 55 kilodaltons that is related to, but distinct from, previously identified retroviral or cellular tyrosine kinases. The protein encoded by blk exhibits tyrosine kinase activity when expressed in bacterial cells. In the mouse and among cell lines, blk is specifically expressed in the B cell lineage. The tyrosine kinase encoded by blk may function in a signal transduction pathway that is restricted to B lymphoid cells.
Influence of preparation time and pitch separation in switching of auditory attention between streams

The ability to consciously switch attention between speakers of interest is necessary for communication in many environments, especially when multiple talkers speak simultaneously. Segregating sounds of interest from the background, which is necessary for selective attention, depends on stimulus acoustics such as differences in spectrotemporal properties of the target and masker. However, the relationship between top-down attention control and bottom-up stimulus segregation is not well understood. Here, two experiments were conducted to examine the time necessary for listeners to switch auditory attention, and how the ability to switch attention relates to the pitch separation cue available for bottom-up stream segregation.
Visible/Infrared/Microwave Agriculture Classification, Biomass, and Plant Height Algorithms

This paper describes the results of a study to determine if visible, infrared, and microwave data is correlated to crop-canopy characteristics (biomass and crop height) and can improve estimates of crop acreage. The objectives were to 1) determine if different crops can be discriminated using multifrequency microwave data, and 2) determine which visible, infrared, and microwave spectral regions can classify crops and correlate well to plant biomass, crop height, and the perpendicular vegetation index (PVI). The study was conducted at Dalhart, Texas, in 1980. Aircraft multispectral data collected during the study included visible and infrared data and active multifrequency microwave data. Ground-truth data from each field consisted of soil moisture, total plant biomass, and crop height. Results indicated that C- (4.75 GHz), L- (1.6 GHz), and P- (0.4 GHz) band active microwave data combined with visible and infrared data maintained or improved crop-discrimination accuracy compared to models using only visible and infrared data. The active microwave frequencies were more sensitive to plant height differences than total biomass differences; the K- (13.3 GHz) and C-bands were sensitive to height variations in short plants, while the P-band was sensitive to differences between tall and short plants.
DSC study of melting and solidification of salt hydrates

Abstract Most salt hydrates, especially those proposed for thermal-energy-storage applications, melt incongruently. In static systems, this property often leads to differences between the enthalpy of fusion and enthalpy of solidification. By means of differential scanning calorimetry (DSC), these differences have been determined for several salt hydrates. For Na2SO4 · 10 H2O, the enthalpy of solidification at or near the peritectic temperature is never more than 60% of the enthalpy of fusion; further cooling leads to a second phase transition at a temperature corresponding to eutectic melting of mixtures of ice and this hydrate. This asymmetrical melting and freezing behavior of Na2SO4 · 10 H2O decreases its potential as an energy-storing medium and also limits its usefulness for temperature calibration of DSC instruments. Sodium pyrophosphate decahydrate, Na4P2O7 · 10 H2O, although in some ways a higher temperature analog of Na2SO4 · 10 H2O, exhibited a smaller discrepancy between the enthalpies of fusion and of solidification; its relatively high transition temperature permits a more rapid solidification reaction than is the case for Na2SO4 · 10 H2O. For Mg(NO3)2 · 6 H2O, a congruently melting compound, the magnitude of ΔH of crystallization equalled ΔH of fusion, even when supercooling occurred; a solid-state transition at 73°C, with ΔH = 2.9 cal g−1, was detected for this hydrate. MgCl2 · 6 H2O, which melts almost congruently, exhibited no disparity between ΔH of crystallization and ΔH of fusion. CuSO4 · 5 H2O and Na2B4O7 · 10 H2O exhibited marked disparities. Na2B4O7 · 10 H2O formed metastable Na2B4O7sd 5 H2O at the phase transition; this was derived from the transition temperature and verified by relating the observed ΔH of transition to heats of hydration. Peritectic solidification of hydrates can be viewed as a dual process: crystallization from the liquid solution and reaction of the lower hydrate (or anhydrate) with the solution; where ΔH of solidification appears to be less in magnitude than the ΔH of fusion, the difference can be attributed to slower reaction rate between solution and the lower hydrate. New or previously unreported values for ΔH of fusion obtained in this study were, in cal g−1: Mg(NO3)2 · 6 H2O, 36; Na4P2O7 · 10 H2O, 59; CuSO4 · 5 H2O, 32; Na2B4O7 · 10 H2O, 33.
Donor Brain Death Mechanisms and Outcomes After Heart Transplantation

We sought to explore whether the cause of donor brain death influenced recipient outcomes after cardiac transplantation. In retrospect, 358 consecutive donors provided cardiac allografts to adult patients undergoing orthotopic heart transplantation at a single urban US medical center from January 2000 through December 2005. Alternate recipients were excluded. Mechanism and cause of donor brain injury and death were divided into five categories: anoxia (nontraumatic) (n=36), blunt head trauma (n=220), penetrating head trauma (n=83), brain tumor/infection (n=7), and cerebrovascular event (n=12). The five subgroups were categorized as traumatic or nontraumatic. The end points of the study were causes of early and late mortality, survival, and rejection rate. There were 59 deaths in the 6-year period. Total and short-term recipient mortality were found to be statistically higher among heart transplant recipients when the donors suffered from traumatic brain death compared to those whose brain death etiology was nontraumatic (P=.045, P=.033, respectively). Rejection rate was similar in all groups (P=.497). In conclusion, donor traumatic brain death was found to be a valid risk factor for recipient mortality after heart transplantation. Caution should be used when evaluating such donors, particularly in the presence of other risk factors.
‘There was so many degrees in slavery ...’: Unfree labor in an antebellum mixed farming community

(1993). ‘There was so many degrees in slavery ...’: Unfree labor in an antebellum mixed farming community. Slavery & Abolition: Vol. 14, No. 2, pp. 35-47.
Hypnosis and the unhypnotizable: a reply to Barber.

Abstract Barber (1980) has recently implied that if low hypnotic responsivity scorers respond favorably to treatments which include a hypnotic induction ceremony, then hypnotic responsivity scores are potentially misleading predictors of therapeutic gain. The logic of Barber's argument and the questionable evidence he presents in support of it are critically examined. Barber has confounded the different yet related issues of hypnotic responsivity and treatment responsivity. An explanation which simultaneously takes into account Barber's data and reaffirms the diagnositic utility of hypnotic responsivity scores is offered.
The two-component system Bacillus respiratory response A and B (BrrA-BrrB) is a virulence factor regulator in Bacillus anthracis.

Bacillus anthracis, a bioterrorism threat as well as an agricultural concern, has complex mechanisms for regulation of its major virulence factors. Genome searches identified the putative two-component system that we designated Bacillus anthracis respiratory response (Brr)A−BrrB. A brrA deletion strain was constructed, and real-time reverse transcriptase polymerase chain reaction and Western blot analysis were used to assess the effect of BrrA−BrrB on levels of virulence factors, the regulator atxA, and growth characteristics. When brrA was deleted, the genes for anthrax toxins (lethal factor, protective antigen, and edema factor) where expressed 4−6-log10-fold less than in the parent Sterne strain. The global regulator atxA was downregulated when compared to atxA in the Sterne strain. Thus, the BrrA−BrrB two-component system positively regulates B. anthracis toxin genes as well as the atxA regulator. Aerobic growth was not affected by the ΔbrrA mutation, but colonies showed differences in morphology, the...
AGU Journals Are Compliant With Research Councils UK Open Access Policies

The Research Councils UK (RCUK) has mandated that after 1 April 2013, papers with RCUK funding be submitted to journals that are compliant with its open-access policy. This policy requires “immediate and unrestricted access to the final published version of papers” and use of the Creative Commons Attribution License (known as CC-BY). Copyright remains with the authors.
Computed tomography of stress fracture

An athletic young female developed gradual onset of pain in the right leg. Plain radiographs demonstrated solid periosteal reaction in the tibia compatible with stress fracture. She stopped sport activites but her pain continued. Follow-up radiographs of the tibia revealed changes suspicious for osteoid osteoma. Computed tomography (CT) scan demonstrated periosteal reaction, but in addition, lucent fracture lines in the tibial cortex were evident. CT obviated the need for more invasive diagnostic procedures in this patient. In selected cases CT may be useful to confirm the diagnosis of stress fracture when plain radiographic or routine tomographic studies are not diagnostic.
Cerebellar unipolar brush cells are targets of primary vestibular afferents: an experimental study in the gerbil

The unipolar brush cell (UBC) is an excitatory glutamatergic interneuron, situated in the cerebellar granular layer, that itself receives excitatory synaptic input on its dendritic brush from a single mossy fiber terminal in the form of a giant glutamatergic synapse. The UBC axon branches within the granular layer, giving rise to large terminals that synapse with both granule cell and UBC dendrites within glomeruli and resemble in morphological and functional terms those formed by extrinsic mossy fibers. So far, the only demonstrated extrinsic afferents to the UBC are the choline acetyltransferase (ChAT)-positive mossy fibers, some of which originate from the medial and descending vestibular nuclei. To ascertain whether UBCs are innervated by primary vestibular fibers, we performed a tract-tracing light and electron microscopic study of the vestibulocerebellum in gerbils. Macular and canal vestibular end-organs were individually labeled by injection of biotinylated dextran amine. After an appropriate survival time, gerbils were then processed for light and electron microscopic analysis of central vestibular projections. In the nodulus and uvula, labeled primary vestibular fibers formed mossy terminals synapsing with both granule cells and UBCs in all of the injected gerbils. Thus, innervation of UBCs by extrinsic mossy fibers carrying static and dynamic vestibular signals represents the first synapse of networks that contribute a powerful form of distributed excitation in the granular layer.
A microscopic model of hydrogen-induced intergranular cracking—II. Steady state crack growth

Abstract A steady state model of hydrogen-induced intergranular crack growth has been developed. It is assumed that the steady state growth of an intergranular crack, screened by dislocations, is controlled by the grain boundary and crack surface diffusion processes of hydrogen. A series of second-order differential equations controlling the diffusion processes of hydrogen in the intergranular crack regions is solved numerically to determine the hydrogen distribution along a steadily moving crack and thereby the change of the ideal work of fracture. The relationship of the stress intensity required for the crack growth to the crack velocity is established as a function of several values of the grain boundary and crack surface diffusivities, the crack length, and the grain size. It is found that while the susceptibility to hydrogen-induced intergranular crack growth increases with increasing hydrogen diffusivities, it decreases with increasing crack length and grain size. The effect of grain size on the growth characteristics of hydrogen-induced intergranular cracking are discussed in terms of the direction change of the hydrogen flux along the moving crack.
Wear mechanism maps of 440C martensitic stainless steel

AISI 440C martensitic stainless steel is the material of choice for the high pressure oxygen turbopump (HPOTP) of the space shuttle main engine (SSME). Tests have been done over a range of sliding speeds from 0.5 to 2.0 m s−1, initial hertzian stresses from 0.915 to 3.66 GPa, and bulk temperatures from −184 °C (liquid oxygen temperature) to 760 °C, which cover the variations thought to exist in the HPOTP. Data are presented in the form of contour wear maps to allow a more direct view of the interdependencies of the major tribological variables than can be obtained with wear data presented vs. a single variable. Wear maps are used as a tool to aid in the determination of regions dominated by a given wear mode. Parametric combinations that result in transitions between wear modes are more easily detected with the use of wear maps. Wear maps can simplify design by identifying combinations of speed, load, and bulk temperature that need to be avoided, because of undesirable wear modes.
Kinetics and mechanism of iron(III)-nitrilotriacetate complex reactions with phosphate and acetohydroxamic acid.

The kinetics and mechanism of the substitution of coordinated water in nitrilotriacetate complexes of iron(III) (Fe(NTA)(OH2)2 and Fe(NTA)(OH2)(OH)-) by phosphate (H2PO4- and HPO42-) and acetohydroxamic acid (CH3C(O)N(OH)H) were investigated. The phosphate reactions were found to be pH dependent in the range of 4−8. Phosphate substitution rates are independent of the degree of phosphate protonation, and pH dependence is due to the difference in reactivity of Fe(NTA)(OH2)2 (k = 3.6 × 105 M-1 s-1) and Fe(NTA)(OH2)(OH)- (k = 2.4 × 104 M-1 s-1). Substitution by acetohydroxamic acid is insensitive to pH in the range of 4−5.2, and Fe(NTA)(OH2)2 and Fe(NTA)(OH2)(OH)- react at equivalent rates (k = 4.2 × 104 and 3.8 × 104 M-1 s-1, respectively). Evidence for acid-dependent and acid-independent back-reactions was obtained for both the phosphate and acetohydroxamate complexes. Reactivity patterns were analyzed in the context of NTA labilization of coordinated water, and outer-sphere electrostatic and H-bonding infl...
Reaction Invariants and Mole Balances for Plant Complexes

Many pharmaceuticals, specialty chemicals, pesticides, or monomers are manufactured in processes with a large number of reaction steps and separations between reactors. These coupled steps lead to ...
Structuring the Macromarket: Lessons from Alexander Hamilton:

As the first U.S. Secretary of the Treasury, Alexander Hamilton exerted significant influence on the formation of governmental policy. This article examines Hamilton's attempt to institute a macrom...
The development of mastication in rodents: From neurons to behaviors

The development of suckling behavior is a fundamental characteristic of mammalian development. The occurrence of this behavior across mammals allows us to extrapolate information from animal models to better understand normal and abnormal masticatory development in infants. This review focuses on prenatal cell, molecular, and morphological changes in rat and/or mouse masticatory muscles, trigeminal motoneurons (Mo5) and mesencephalic trigeminal neurons (Me5) that accompany the development of suckling behavior. A special emphasis is placed on N-methyl-d-aspartate (NMDA) receptor subunit expression because of the important role that NMDA receptors play in the production of rhythmical jaw movements and neuronal development. Prenatally the timing of NMDA subunit changes follows neuromuscular junction formation in masticatory muscles, and is coincident with the emergence of rhythmical jaw movements and in vitro rhythmical trigeminal activity. Our data suggest that NMDA receptor subunit changes in Mo5 and Me5 are synchronized with the emergence of rhythmical jaw movements and trigeminal motor activity.
Confidence Limits in the Non-Parametric Case

Abstract The purpose of this article is to give a survey 1 of certain methods available for finding confidence limits when nothing is assumed about the population from which a sample has been drawn except possibly that it has a continuous distribution. The following three cases are treated: a confidence band for the unknown cumulative distribution function, a confidence interval for the proportion of a population for which the variate is smaller (or larger) than a given value, and confidence intervals for quantiles. The results have been known for many years, but have often been accessible only to those who were able to follow rather involved mathematical arguments. It is the purpose of this paper to state certain important results without referring to any mathematical proofs. 1I should like to thank Professor Wolfowits for pointing out the need for such a survey.
Longitudinal relationships between visual acuity and severe depressive symptoms in older adults: the Salisbury Eye Evaluation study

Objectives: To assess the longitudinal relationship between visual acuity (VA) and depressive symptoms (DSs) among older adults.Methods: A population-based sample of 2520 white and black individuals aged 65–84 years in 1993--1995 was assessed at baseline and at two, six, and eight years later. Presenting and best-corrected VA was assessed using early treatment diabetic retinopathy study chart. DSs were assessed using the severe depression subscale of General Health Questionnaire 28. Latent growth curve models estimated VA and DS trajectories and age-adjusted associations between trajectories.Results: Best-corrected logMAR VA worsened over time (slope = 0.026, intercept = 0.013, both p < 0.001). No change in DS over time was observed (slope = −0.001, p = 0.762; intercept = 1.180, p < 0.001). However, a small change in DS was observed in participants who completed all rounds (slope = 0.005, p = 0.015). Baseline VA levels correlated with baseline DS levels (r = 0.14, p < 0.001). Baseline DS was associated wi...
Sensor Placement and Structural Damage Identification from Minimal Sensor Information

A method of prioritizing sensor locations on a flexible structure for the purpose of determining damaged structural elements from measured modal data is presented. This method is useful in applications where practicality dictates only a small subset of the total structural degrees of freedom can be instrumented. In such cases, it is desirable to place sensors in locations yielding the most information about the damaged structure. No a priori knowledge of the damage location is assumed. The prioritization is based on an eigenvector sensitivity analysis of a finite element model of the structure. In addition, the dual problem is presented and solved, which determines the observability of change in the measured elgenstracture from the instrumented degrees of freedom. This analysis is used to determine the extent to which damage can be localized. An analytical example is presented that illustrates the relationship between the number of measured modes, the number of instrumented degrees of freedom, and the extent to which damage can be localized. Additionally, an analysis of an experimental cantilevered eight-bay truss assembly consisting of 104 elements instrumented with eight single-axis accelerometers is presented. The extent to which structural damage can be localized from the measurement data is limited by the number of measured modes.
Glycogen structure and utilization in Allomyces macrogynus

After 72 h of cultivation on defined medium, mycelia of Allomyces macrogynus contain 36, 7.3, and 4.2% protein, lipid, and glycogen, respectively. Isolated and purified glycogen is water soluble and iodophilic and consists of at least 99% anhydroglucose. After partial hydrolysis of glycogen, maltose ( α -1,4-linkage) and isomaltose ( α -1,6-linkage) are the only detectable disaccharides. Absorption spectra of glycogen-iodine complexes are similar to those observed with glycogens from other organisms. The β -amylase hydrolysis limit (44–48%) and average chain length (11–12 glucose units) of the polysaccharide indicate that it is a typical glycogen. During starvation, as much as 48% of the stored glycogen is depleted while protein and lipid utilization is 45 and 25%, respectively. However, 72% of the dry weight loss during starvation occurs as a result of protein utilization. Glycogen from unstarved and starved mycelia shows no significant differences as judged by comparison of the iodine complex spectra, β -amylase limits, and average chain lengths. The quantity of a soluble galactose polymer increases more than twofold during starvation. Although the glycogen utilized during this period can easily account for the galactan increase, it is not known whether or not there is a direct relationship between these two polysaccharides. Although sporulation occurs during starvation, this work does not permit any definite conclusions regarding a relationship between sporogenesis and changes in the amounts of mycelial constituents.
Therapeutic goals and treatment options for prevention of stress ulcer syndrome

Stress ulcer syndrome, the occurrence of acute upper gastrointestinal bleeding or perforation from stress-related mucosal damage, is a significant cause of morbidity and mortality in critically ill patients. The mortality rate in critically ill patients who have bled from stress ulcers ranges from 50 to 77 percent, whereas the mortality rate for similar patients without stress ulcer bleeding ranges from 9 to 22 percent. The mortality rate may be as high as 90 percent in patients with clinically overt bleeding; as many as one-third of these deaths can be directly related to bleeding. Prophylactic therapy for prevention of stress ulcer bleeding is based on three premises: (1) morbidity and mortality related to stress ulcer syndrome are significant; (2) the population at risk can be identified prior to bleeding; and (3) therapy that decreases gastric acidity or improves gastric mucosal defense mechanisms will prevent ulcer formation or progression to bleeding. A review of prospective clinical studies utilizing prophylactic therapy in critically ill patients and patients undergoing surgery revealed a 17 percent overall bleeding rate for placebo groups compared with lower bleeding rates for antacid- and histamine (H2)-receptor-antagonist-treated groups (4 and 7 percent, respectively). Studies varied greatly in definition of bleeding, dosage regimens, and gastric pH goals. The need to measure gastric pH during treatment is controversial, and the optimal pH goal and the length of time for which it must be maintained remain unknown. Controversy exists as to the best therapeutic option for prophylaxis of stress ulcer syndrome, but when prevention of clinically significant bleeding is the therapeutic goal, antacids and H2-receptor antagonists appear to be equally efficacious.
Raman spectroscopic evidence of crystalline phosphate precursor to bone apatitic mineral

ABSTRACT Bone is a highly specialized connective tissue comprised of cross-linked collagen fibers interspersed with apatitic mineral crystallites of various sizes, shapes, orientation, and composition. However, the nucleation, growth, and propagation of mineral crystallite into the collagenous matrix are not clearly understood. By using a research grade inverted microscope fitted with a line-shaped 830 nm lase r and spectrograph, we show that the Raman scatter from mineralizing cell cultures in an incubation chamber can be collected and monitored directly through the bottom of the well-plates over a period of 24 hours. In our studies, murine-derived MC3T3 cells were incubated at 37°C in the presence of 5% CO 2 and 85% humidity. Results show a gradual shift in the phosphate 1 apatitic band center (955957 cm -1 ) during the first hour of mineralization. The phosphate 1 apatitic band width also narrowed during this time. To quantify the amount of crystal growth in vivo , we used a calibration curve derived from X-ray powder diffraction and Raman studies performed on a series of synthetic carbona ted apatites and deproteinated mouse femoral specimens. Mineralization in neonatal mouse calvari al culture was observed along the lambdoid suture. Deposition proceeded in a stepwise fashion over the course of ~30 h. Keywords: Mineralization, apatite, Raman, calvari um, osteoblast, octacalcium phosphate
The picture theory of meaning

The general features of a picture theory of meaning (PTM) are stated. The PTM is then applied to a particular ontological perspective, and suggestions are made for generalizing the PTM to most ontological perspectives. Several ways around the classic problem for the PTM-that the language used to describe a situation must have at least one more component than the situation described-are offered.
Relations of Physical Habitat to Abundance of Four Nongame Fishes in High-Plains Streams: A Test of Habitat Suitability Index Models

Abstract We examined relations between habitat variables and biomasses of white sucker Catostomus commersoni, creek chub Semotilus atromaculatus, longnose dace Rhinichthys cataractae, and common shiner Notropis cornutus from data collected at 29 sites in the Horse Creek drainage of eastern Wyoming. Few of the habitat variables that have been used in habitat suitability index (HSI) models were correlated with the biomass of the four species. Also, composite HSI scores were not correlated with the biomass of the four species. However, abundances of these species were related to other habitat features that we measured and analyzed by correlation and multiple-regression analysis. White sucker biomass was correlated with main-channel run habitat, shade, turbidity, water temperature in August, and large woody debris. Creek chub biomass was related to the coefficient of variation (SD/mean) in current velocity and to submerged aquatic vegetation, average current velocity, and main-channel pool habitat. Longnose d...
Incidence of charcoal rot of sorghum and soil populations of Macrophomina phaseolina associated with sorghum and native vegetation in Somalia

Studies were conducted in the Bay Region of Somalia to determine the incidence of charcoal rot in sorghum incited by Macrophomina phaseolina and the soil population of M. phaseolina in sorghum fields and areas of native vegetation. Charcoal rot was detected in 34 of 40 sorghum fields. Incidence (percent sorghum hills with diseased plants) in the four regional districts was 21, 70, 20 and 35% (mean of 15 hills/field and 10 fields/district) for Baidoa, Burhakaba, Dinsoore and Quansadhere, respectively. Soil collected from the 40 sorghum fields and from 40 native vegetation sites (10 in each district) all contained M. phaseolina. Mean soil populations for sorghum fields and native vegetation sites were 25.2 and 2.5 microsclerotia g−1 soil, respectively. Soil populations of M. phaseolina in sorghum fields were significantly (p=0.05) different from populations in native vegetation sites and ranged from 7 to 107 and 0.1 to 14.0 microsclerotia g−1 soil, respectively. Incidence of charcoal rot in sorghum was positively correlated with soil populations of M. phaseolina (r=0.53, p= 0.01). Correlation between ratoon failure and disease incidence was also highly significant (r=0.48, p=0.01). Correlation between ratoon failure and soil population of M. phaseolina was not significant (r=0.17, p=0.10). Only one out of 30 seed lots of sorghum grown in the Bay Region contained seed infected with M. phaseolina.
Corporate Strategy and Public Policy in Saudi Arabia

Abstract This paper examines the nature of public sector planning and its impact on businesses strategies and plans in Saudi Arabia, a resource-strong country. With a stable government and a dominant public sector, the Saudi environment typifies conditions in which a firm's strategies need to be in accord with government plans and priorities. Insights are gained by utilizing a framework of resource spending, conceptualized in three phases: revenue surplus, revenue deficit and revenue balance. The paper concludes that business firms should develop timely plans to capitalize on opportunities and to cope with pressures during each of the phases.
The effects of nutrition on survival and fecundity in Florida mosquitoes. Part 2. Utilization of a blood meal for survival.

Unfed 2- to 5-day-old females of different species of Florida mosquitoes were fed ad lib. a meal of chicken blood to repletion and analyzed for weights and calorie intake, survival, and accumulation and depletion of energy reserves. Females ingested blood meals with wet weights of 2.5 to 4 times greater than their own wet weights and dry weights of 1.2 to 1.7 times greater than their own dry weights. Efficiency of blood ingested for survival was highest in Aedes aegypti (84.5 hr/cal.) followed by Aedes taeniorhynchus (68.5 hr/cal.) and A. sollicitans, Anopheles quadrimaculatus and Psorophora confinnis (44.0 to 48.4 hr/cal.). Glycogen and triglycerides accumulated after blood ingestion, reaching maximum values within 24 to 72 hr before decreasing to stable values in the next 24 to 96 hr. Part of the energy reserves synthesized from blood prolonged survival of unfed females from 3 days in An. quadrimaculatus to 8 days in A. taeniorhynchus more than the starved females, and the remainder of the reserves was stored in yolk of matured oocytes. It is concluded that a blood meal provides sufficient reserves to enable the species investigated to survive long enough to produce a batch of eggs.
Flip-flopping binary black holes

We study binary spinning black holes to display the long term individual spin dynamics. We perform a full numerical simulation starting at an initial proper separation of $d\ensuremath{\approx}25M$ between equal mass holes and evolve them down to merger for nearly 48 orbits, 3 precession cycles, and half of a flip-flop cycle. The simulation lasts for $t=20\text{ }000M$ and displays a total change in the orientation of the spin of one of the black holes from an initial alignment with the orbital angular momentum to a complete antialignment after half of a flip-flop cycle. We compare this evolution with an integration of the 3.5 post-Newtonian equations of motion and spin evolution to show that this process continuously flip flops the spin during the lifetime of the binary until merger. We also provide lower order analytic expressions for the maximum flip-flop angle and frequency. We discuss the effects this dynamics may have on spin growth in accreting binaries and on the observational consequences for galactic and supermassive binary black holes.
Diabetes, Related Conditions, and Dementia

This manuscript provides a brief review of the epidemiologic evidence linking type 2 diabetes (T2D) and its precursor conditions, elevated adiposity and hyperinsulinemia, to dementia. Elevated adiposity in middle age is related to a higher risk of dementia but the data on this association in old age is conflicting. Hyperinsulinemia, a consequence of higher adiposity and insulin resistance is also related to a higher risk of dementia, including late onset Alzheimer's disease (LOAD). Studies have consistently shown a relation of T2D with higher dementia risk, but the associations are stronger for vascular dementia compared to LOAD. One implication of these associations is that strategies used to prevent T2D can be used to prevent dementia. Several studies in the prevention and treatment of T2D are currently measuring cognitive outcomes and will provide information on whether T2D treatment and prevention can prevent cognitive decline and dementia.
Proton transport by bacteriorhodopsin through an interface film.

Interface films of purple membrane and lipid containing spectroscopically intact and oriented bacteriorhodopsin have been used as a model system to study the function of this protein. Small positive charges in surface potential (<1 mV) are detected upon illumination of these films at the air-water interface. These photopotentials, are not affected by overlaying the interface film with a thin layer (0.3 mm) of decane. However, they are dramatically increased when lipid soluble proton carriers FCCP or DNP are added to the decane. The polarity of the photopotential indicates that, in the light, positive charges are transported through the interface from the aqueous to the organic phase. The action spectrum of the photopotential is identical to the absorption spectrum of bacteriorhodopsin. Since bacteriorhodopsin molecules are oriented with their intracellular surface towards the aqueous subphase, the characteristics of the photopotential indicate that in the light bacteriorhodopsin translocates protons from its intracellular to its extracellular surface. The kinetics of the photopotential reveal that the rate and extent of proton transport are proportional both to the fraction of bacteriorhodopsin molecules excited and to the concentration of proton acceptor. The photopotentials result from changes in the ionic distribution across the decane-water interface and can be cancelled by lipid soluble anions.
Dose-response relationships for resetting of human circadian clock by light

Since the first report in unicells, studies across diverse species have demonstrated that light is a powerful synchronizer which resets, in an intensity-dependent manner, endogenous circadian pacemakers. Although it is recognized that bright light (approximately 7,000 to 13,000 lux) is an effective circadian synchronizer in humans, it is widely believed that the human circadian pacemaker is insensitive to ordinary indoor illumination (approximately 50-300 lux). It has been proposed that the relationship between the resetting effect of light and its intensity follows a compressive nonlinear function, such that exposure to lower illuminances still exerts a robust effect. We therefore undertook a series of experiments which support this hypothesis and report here that light of even relatively low intensity (approximately 180 lux) significantly phase-shifts the human circadian pacemaker. Our results clearly demonstrate that humans are much more sensitive to light than initially suspected and support the conclusion that they are not qualitatively different from other mammals in their mechanism of circadian entrainment.
Myocardial perfusion and contrast echocardiography: review and new perspectives.

Myocardial perfusion can be assessed qualitatively and quantitatively with new ultrasound contrast techniques. This article reviews progress and problems in this area, discussing intracoronary and aortic root injections in animals and humans. The technique has great potential clinical application for the identification of coronary flow reserve, and the assessment of the need for and outcome of coronary revascularization procedures. It may allow direct measurements of regional myocardial perfusion. (ECHOCARDIOGRAPHY, Volume 8, January 1991)
Protein indirect relaxation effects in exchange-transferred NOESY by a rate-matrix analysis

Abstract The influence of relaxation by protein protons on ligand-ligand intensities measured by two-dimensional exchange-transferred nuclear Overhauser spectroscopy (ET-NOESY) is examined by simulation studies using a rate-matrix analysis. Evidence that effects from the protein protons can be significant is demonstrated by experimental data from the complex NADH · lactate dehydrogenase. Both protein and ligand protons are explicitly considered in a rate matrix comprising chemical-exchange and NMR relaxation rates. In the fast-exchange limit with respect to magnetic relaxation rates, the matrix equation simplifies to a symmetrical form, so that standard symmetric matrix diagonalization methods can be used to solve the equation. Computer simulation studies for a three-spin system show that, for certain geometries, protein protons have significant indirect effects on ligand-ligand cross-peak intensities which could lead to inaccurate estimates for the distances between ligand protons. The simulation studies also show that T1 of the free ligand influences the observed exchange-transferred NOE. Analysis of experimental ET-NOE data finds that protein relaxation effects are present; a comparison between expected ET-NOESY intensities based on crystallographic coordinates and those measured experimentally for NADH-lactate dehydrogenase indicates a significant indirect effect from Ser 137 Hα of the protein to the ligand-ligand cross peak H1′-H4′ of the ribose of the ribonicotinamide moiety