cssi/SciSciGPT-SciSciNet huggingface dataset:
Phenotypic correlations among quality traits of fresh and dry-cured hams.

In this study, fresh and processing quality traits were collected on a total of 312 Country Hams. Phenotypic correlations between traits were estimated and numerous values were significantly different (P < 0.05) from zero. Yield was significantly correlated with several fresh pork quality traits measured on the fresh hams, including subjective color (0.34) and lipid percentage (0.32). Some meat color traits were significantly correlated, including associations between the color scores taken on the fresh and cured hams. Correlations between fresh pork quality traits were also determined, with results showing significant correlations between ultimate pH and other pork quality traits. The results indicate that yield can be maximized if hams with good fresh pork quality parameters are used for curing. The correlations estimates are helpful for understanding of the biological mechanisms behind the production of dry-cured hams and can potentially be used to improve the efficiency of the dry-cured ham production chain.
Laser light induced modulations in metabolic activities in human brain cancer

The role of low visible or near infra-red laser intensity in suppressing metabolic activity of malignant human brain cancer (glioblastoma) cells was investigated through the application of either a continuous wave 633nm HeNe or a pulsed picosecond 1,552nm wavelength laser. Human glioblastomas were exposed in their growth culture medium with serum for several energy doses. For both types of laser exposures the glioblastomas exhibited a maximal decline in the metabolic activity relative to their respective sham control counterparts at 10 J/cm2. The cellular metabolic activities for various treatment doses were measured through the colorimetric MTS metabolic assay after the laser exposure. Interestingly, addition of (the enzyme) catalase in the growth medium prior to the laser exposure was found to diminish the laser induced metabolic suppression for all fluence treatment conditions, thus suggesting a functional role of H2O2 in the metabolic suppression. Taken together, our findings reveal that visible or near infra-red low level light exposures could potentially be a viable tool in reducing the metabolic activity of cancers; evidence at hand implicates a role of light induced H2O2 in bringing about in part, suppression in the metabolic activity. Due to the cellular "biphasic" response to the laser exposure, further research needs to be undertaken to determine exposure parameters which would optimize metabolic and cellular growth suppression in-vivo.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Materials science: on the straight and narrow.

Nanoscale chemical patterns written on a substrate can direct the self-assembly of polymer overlayers with remarkable precision. These polymer films, in turn, can be used as templates for nanofabrication.
Non-epithelial tumors of the nasal cavity, paranasal sinuses, and nasopharynx: A clinicopathologic study(III. Cartilaginous tumors (chondroma, chondrosarcoma))

In a review of non-epithelial tumors involving the nasal cavity, paranasal sinuses, and nasopharynx, 256 lesions, 156 benign and 100 malignant, were identified. of these, 17 were cartilaginous neoplasms, 7 chondromas and 10 chondrosarcomas. The clinical findings associated with these cartilaginous tumors are described, the histologic features illustrated, results of therapy presented, and clinicopathologic correlations made. Chondromas were small asymptomatic incidentally found nodules which were successfully treated by limited local resections. The prognosis of the chondrosarcomas depended upon: 1) the location and extent of the lesion; 2) the adequacy of the surgical therapy; and 3) the degree of differentiation of the tumor.
Network characterization of piezoelectric stacks for smart structures

We provide exact equivalent network representations for the electromechanical behavior of crystal stacks that are piezoelectrically driven in simple thickness modes of vibration. These configurations are archetypes for many sensors and actuators under development for smart structure applications. The stacked configuration may consists of any number of layers, with each layer comprised of an homogeneous, but arbitrarily anisotropic crystal medium, whose constitutive equations are linear. No further limitations are imposed upon the elastic, piezoelectric, and dielectric coefficients of each stratum other than those required by energy considerations.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The View from Economics: Discussion of Castle's Conceptual Framework

It is a tall order to develop a conceptual framework for use by at least four distinct academic disciplines. I have the far simpler task of assessing the framework from the perspective of a single discipline (economics). Castle's emphasis on assets and asset formation is useful. Four categories of assets are identified: natural, man created, human, and social capital. Static neoclassical economic theory explains flows (value created during one period of time) but largely ignores assets (also called stocks, which are the net accumulation of flows over time). Over the past several decades, dynamic theories and models that incorporate assets and that explain how assets accumulate over time have been developed, yet regional and rural economists continue to use empirical models (such as export base and input-output) that ignore asset creation and deal only with the flow of income or employment. While this is partly because of the scarcity of spatially disaggregated data required to implement asset-endogenous models of regions or rural areas, a conceptual framework that stresses the long run is needed if we are to gain a deeper understanding of rural well-being. Why is an asset approach important? In a market economy, claims on the flows of economic value are based largely on the ownership of assets. While incomes can be transferred, transfers do not represent the best long-run solution for most low income communities, households, or individuals. Dealing only with flows in rural economic studies ignores the issue of local capacity to create economic well-being and to do so in a self-directed manner. Regional income, whether the money-measured variety or the nonmarket psychic income variety, is generated largely by the capacity inherent in place-specific assets. C stle believes that the concept of social capital is useful in rural studies, a point on which I agree. Critics believe some social theorists have a rosy view of social capital that ignores material constraints, class divisions, and power relations. These are reasons to improve nd enrich the concept, not to reject it. Human capital theory enriched economists' vision of "homo economicus" and led to an-
Sparse biologically-constrained optimal perturbation of gene regulatory networks

This paper derives a sparse optimal perturbation of gene regulatory networks by determining the optimal perturbation of the minimal number of individual genes that force the network to settle into desired equilibrium states. Previous efforts have led to intervention in gene regulatory networks by deriving the optimal perturbation of the state probability transition matrix. Current technology in molecular biology, however, is limited to perturbation of the state of individual genes, not the state probability transition matrix. Our computer simulation experiments on the Human melanoma gene regulatory network demonstrate the superiority of the proposed approach to gene regulation in comparison to the previous methods based on the marginal of the optimal perturbation of the probability transition matrix of the network.
Activity and properties of (-)-S-adenosyl-L-methionine: magnesium-protoporphyrin IX methyltransferase in crude homogenates from wheat seedlings.

Abstract A direct, rapid assay for the enzyme S-adenosylmethionine:magnesium-protoporphyrin IX methyltransferase (EC 2.1.1.11) is presented. Using the assay developed, the effect of temperature and pH on the activity of the enzyme in a crude homogenate of etiolated wheat seedlings was studied. The pH optimum was found to be 7.7 using phosphate buffer; the enzyme exhibited maximum activity at 37 °C although activity was found to be nearly optimal at 25 °C. The Km (pH 7.7, 25 °C) values determined for Mg-protoporphyrin IX and S-adenosylmethionine were 36 and 48 μM, respectively. Treatment of the crude preparation from etiolated wheat with n-butanol to remove endogenous pigments did not result in a decrease in specific activity of the preparation. A crude preparation from green wheat seedlings when treated with butanol exhibited an activity comparable with that of the etiolated wheat preparation so treated thereby demonstrating that this assay could be used in green plant systems.
NIGHT BLINDNESS AND THE MECHANISM OF CONSTITUTIVE SIGNALING OF MUTANT G90D RHODOPSIN

The G90D rhodopsin mutation is known to produce congenital night blindness in humans. This mutation produces a similar condition in mice, because rods of animals heterozygous (D+) or homozygous (D+/+) for this mutation have decreased dark current and sensitivity, reduced Ca(2+), and accelerated values of tau(REC) and tau(D), similar to light-adapted wild-type (WT) rods. Our experiments indicate that G90D pigment activates the cascade, producing an equivalent background light of approximately 130 Rh* rod(-1) for D+ and 890 Rh* rod(-1) for D+/+. The active species of the G90D pigment could be unregenerated G90D opsin or G90D rhodopsin, either spontaneously activated (as Rh*) or in some other form. Addition of 11-cis-retinal in lipid vesicles, which produces regeneration of both WT and G90D opsin in intact rods and ROS membranes, had no effect on the waveform or sensitivity of dark-adapted G90D responses, indicating that the active species is not G90D opsin. The noise spectra of dark-adapted G90D and WT rods are similar, and the G90D noise variance is much less than of a WT rod exposed to background light of about the same intensity as the G90D equivalent light, indicating that Rh* is not the active species. We hypothesize that G90D rhodopsin undergoes spontaneous changes in molecular conformation which activate the transduction cascade with low gain. Our experiments provide the first indication that a mutant form of the rhodopsin molecule bound to its 11-cis-chromophore can stimulate the visual cascade spontaneously at a rate large enough to produce visual dysfunction.
Using Kolb's Experiential Learning Cycle to improve student learning in virtual computer laboratories

In information security education, learning experiences that involve hands-on experimentation are extremely important. However, information security topics are challenging to teach in traditional computer laboratories mainly due to restrictive information technology policies. In the literature, virtual computer laboratories have been proposed to address the challenges of providing students with hands-on learning experiences in information security. While the literature mainly focuses on technical aspects of virtual computer laboratories and related hands-on activities, pedagogical aspects of hands-on activities are overlooked. Our experiences with a virtual computer laboratory have shown that hands-on activities which are designed based on a prescriptive, step-by-step approach do not always achieve the expected learning outcomes. In this paper, we propose Kolb's Experiential Learning Cycle as a framework to design hands-on activities in virtual computer laboratories, and we argue that hands-on activities designed based on this framework enhance student learning outcomes. We illustrate how the stages of Kolb's model can be incorporated into hands-on activities and present results from two empirical studies to test the effectiveness of the proposed framework. The empirical findings in the first study suggest that hands-on activities designed based on the proposed framework are more likely to increase student interest and competency compared to step-by-step hands-on activities. In the second study, the collected data is analyzed using structural equation modeling to determine the relationships among the factors affecting student learning outcomes as a result of hands-on activities. The results of the second study show that student-to-student interaction is an important factor determining student learning experiences. Hands-on learning is studied in virtual computer laboratories.Cookbook activities do not achieve comprehensive learning.To enhance student learning, Kolb's model is proposed to design hands-on activities.The benefits of Kolb's model are investigated in the information security domain.The proposed approach enhances student learning in virtual computer laboratories.
Influence of Limonin on Consumer Preference of Processed Grapefruit Juice

A batch of Florida frozen concentrated grapefruit juice (GJ) was reconstituted with limonin addition to produce 5 juices containing from 2.3 (control) to 11.0 ppm limonin, 10° Brix, and 8.5 Brix: percent acid. Consumers from 4 large U.S. cities evaluated the juices for flavor and 5 additional quality attributes, and juice preference. Flavor means varied within an acceptable range and were affected negatively by limonin concentration. GJ users rated products significantly higher than did nonusers. Preference by users and nonusers was least for the highest limonin content juice. Bitterness and tartness perception increased with increasing limonin content whereas sweetness perception decreased. All samples were judged somewhat too bitter and tart, and not quite sweet enough.
Towards accurate modeling for protein rigidity analysis

We evaluate the performance of the modeling in KINARI, our pebble-game rigidity analysis system, on a benchmark data set of 32 PDB files used by the Gerstein Lab to validate the RigidFinder algorithm. For this we use a novel evaluation method, called the cluster decomposition score. This is adapted from the B-cubed score from the information retrieval literature, which is used as a comparative score on two clusterings of the same data. We focus on the the most extensively used tuning parameter in rigidity analysis, the hydrogen bond energy cutoff. We also propose a new modeling methodology for hydrogen bonds, where those with energies lower than the cutoff, instead of being discarded, are modeled with a weaker constraint. For the 5 largest proteins (501 residues or more), the KINARI decompositions scored significantly better than the crude baseline, indicating that the parameterization used is reliable for larger proteins. For most of the proteins including all hydrogen bonds leads to the best scores. For the others, where a cutoff improved the score, our new modeling methodology matched or improved results for 9 out of 10 PDBs. We investigate the sensitivity of the cluster decomposition score with case studies on pyruvate phosphate dikinase and phosphotransferase.
Payment for cancer prevention. Community and government perspectives.

PURPOSE The development of a stronger interest in cancer prevention and early detection programs has led to the opportunity for mechanisms to provide adequate financial support at the individual, practitioner, and community levels. This discussion draws on the experiences of public health systems and emerging models for personal care to describe a framework for consideration of prevention and early detection funding, and to discuss the prospects of funding. OVERVIEW Some prevention and early detection services are financed appropriately through individual payment mechanisms and can be covered in indemnity and capitated insurance plans. Population-based approaches to prevention do not fit this model, however, and need to be financed at the community level, through taxes or other shared financing schemes. CLINICAL IMPLICATIONS Lack of public understanding of the differences between individual- and population-based prevention makes resource development difficult. Practitioners interested in such approaches need to join with others in the community to gain support. Long-term support of community efforts currently remains unclear. Although the actions identified are essential, they are not sufficient to support a comprehensive cancer prevention and detection program fully. The concerned clinician should become a part of the community-wide effort. This may be done individually, through participation on a local board of health or a hospital-based health promotion coalition. This also may be achieved through associations such as the local medical society or the local American Cancer Society.
AGA technical review on nonalcoholic fatty liver disease

Abstract Nonalcoholic fatty liver disease (NAFLD) represents a spectrum of conditions characterized histologically by mainly macrovesicular hepatic steatosis and occurs in those who do not consume alcohol in amounts generally considered to be harmful to the liver. There are 2 histologic patterns of NAFLD: fatty liver alone and steatohepatitis. NAFLD is an increasingly recognized cause of liver-related morbidity and mortality. In this review, the existing literature regarding the nomenclature, clinical and histologic spectrum, natural history, diagnosis, and management of this condition are discussed. GASTROENTEROLOGY 2002;123:1705-1725
Equal Pay for Comparable Work: Stimulus for Future Civil Service Reform:

The equal pay for work of comparable value movement forces reexamination not only of the processes of the merit system but also its outcomes. This study identifies key issues in equal pay for compa...
Variability in Measured Bedlo Ad-Transport Rates

: Variability in bedload-transport rates during constant water discharge is an inherent part of the bedload-transport process. Although this variability has been measured extensively in the laboratory, similar information generally is not available from field measurements. During a four-day period of nearly constant water discharge, four sets of consecutively collected bedload samples, ranging from 43 to 120 samples, were obtained at the same cross channel location using a standard 65-pound Helley-Smith bedload sampler. When the measured transport rates are converted to dimensionless rates and plotted as cumulative frequency distributions, they show good agreement with a theoretical probability distribution function of rates derived for the case of ripples on dunes. The distributions show that during constant water discharge individual measured rates at a fixed point vary from near zero to four times the mean rate, and 60 percent of the sampled rates will be less than the mean. Because of the large variation in transport rates that occurs at every location in the cross section, many observations are required to establish an accurate estimate of the mean rate at any given location.
Biliary stent migration presenting with leg pain.

Although the therapeutic benefits of endoscopic retrograde cholangiopancreatography (ERCP) usually outweigh the risks, there can be rare complications, including stent migration leading to perforation, intestinal obstruction or penetration. An 87-year-old woman presented with symptomatic choledocholithiasis. Two previous endoscopic attempts at stone removal were unsuccessful. On repeat ERCP at our institution, multiple large stones were removed, but complete duct clearance could not be achieved. A plastic biliary stent was placed with plans to reattempt in 6 weeks. Postoperatively, she had mild back pain radiating into her right leg that gradually worsened to the point where she was unable to ambulate. An abdominal CT scan showed the distal aspect of the biliary stent extending through the wall of the duodenum with the tip positioned within the right psoas muscle. The stent was successfully removed via a rat-toothed forceps. Our case illustrates an extremely rare complication of biliary stent placement.
Senescence-associated decline in hepatic peroxisomal enzyme activities corresponds with diminished levels of retinoid X receptor alpha, but not peroxisome proliferator-activated receptor alpha.

Abstract Aging is associated with alterations in hepatic peroxisomal metabolism and susceptibility to hepatocarcinogenicity produced by agonists of peroxisome proliferator-activated receptor alpha (PPARα). Mechanisms involved in these effects are not well understood. However, as a heterodimer with retinoid X receptor alpha (RXRα), PPARα regulates transcription of genes involved in oxidative stress, cell proliferation and apoptosis. Modulating these important cell functions as a result of aging may be responsible for altered hepatic peroxisomal responses in the senescent liver. Therefore, we investigated hepatic apoptosis, and peroxisomal β-oxidation activity, a major source of H 2 O 2 , as well as the activity of the peroxisomal anti-oxidant enzyme catalase, in male Fischer-344 rats of four age groups (4, 10, 50 and 100 week old). We further quantified protein levels of both PPARα and RXRα in these animals. Data show that peroxisomal β-oxidation and catalase activities were significantly lower in livers of the 100 week old animals compared with other age groups, while percentage of apoptotic hepatocytes were identical in all animal age groups. However, aging had no effect on hepatic PPARα protein levels. In the senescent group, the level of decline in both peroxisomal enzyme activities of 30% was surprisingly similar to the decline observed in the hepatic expression of the RXRα protein. Results from this study suggest that alterations in peroxisomal metabolism observed in the senescent liver may be a result of the decline in the availability of RXRα receptor, and not the primary PPARα receptor. On the other hand, PPARα-independent mechanisms appear to play a role in controlling apoptosis in the senescent liver.
Organization of the human motor system as studied by functional magnetic resonance imaging

Blood oxygenation level dependent functional magnetic resonance imaging (BOLD fMRI), because of its superior resolution and unlimited repeatability, can be particularly useful in studying functional aspects of the human motor system, especially plasticity, and somatotopic and temporal organization. In this survey, while describing studies that have reliably used BOLD fMRI to examine these aspects of the motor system, we also discuss studies that investigate the neural substrates underlying motor skill acquisition, motor imagery, production of motor sequences; effect of rate and force of movement on brain activation and hemispheric control of motor function. In the clinical realm, in addition to the presurgical evaluation of neurosurgical patients, BOLD fMRI has been used to explore the mechanisms underlying motor abnormalities in patients with neuropsychiatric disorders and the mechanisms underlying reorganization or plasticity of the motor system following a cerebral insult.
Small-signal characteristics of lateral transistors

Abstract This paper considers the small-signal characteristics of lateral transistors made on epitaxial layers of finite thickness, as is the case in most monolithic integrated circuits. For tractability and ease of comprehension, one-dimensional approximations are made, but these are usually adequate for predicting the essential features of the frequency response. Various circuit models are proposed, including the low-frequency charge control model whose validity can be extended to higher frequencies by the use of frequency-dependent elements. Alternatively, multilump models with frequency-independent elements can be used at the higher frequencies. Experimental data on small-signal common-emitter current gain is presented in support of the theory.
564 TREATMENT OF GLUTATHIONE SYNTHETASE DEFICIENT FIBROBLASTS BY INHIBITION OF γ-GLUTAMYL TRANSPEPTIDASE WITH SERINE-BORATE

Glutathione synthetase (GSH-S) deficiency (5-oxoprolinuria) results in decreased cellular glutathione (GSH) content (10-20% of normal), and secondary over-production of 5-oxoproline. γ-glutamyl transpeptidase (GGTP) is the primary catabolic enzyme for GSH, and inhibition of this enzyme might thus be an approach to correcting the consequences of GSH-S deficiency. L-serine inhibits fibroblast GGTP. Inhibition is markedly enhanced by sodium borate buffer, 20 mM serine-20 mM borate causing>95% inhibition. Serine-borate added to Eagle's MEM produced a dose and time dependent increase in GSH content of GSH-S deficient cultured fibroblasts. GSH content was doubled at 24 hours with 40 mM serine-40 mM borate. Borate alone was without effect. Conversion of 14C-glutamic acid to 5-oxoproline by GSH-S deficient cells was decreased by 70% to near normal levels by 24-hour pre-treatment with 40 mM serine-borate. The increased cell GSH content may block overproduction of 5-oxoproline from excess γ-glutamylcysteine by feed-back inhibiting γ-glutamylcysteine synthetase. Treatment produced no apparent toxicity; cell amino acid concentrations were unaffected other than an increase in serine and phosphoserine. The study demonstrates the possible therapeutic value of an inhibitor of a major catabolic enzyme for a substrate decreased secondary to a deficiency of its synthetic enzyme.
Acidic pH Hyperpolarizes Nasal Potential Difference

Nasal potential difference (NPD) has served as a non-invasive diagnostic method for cystic fibrosis (CF) a disease of chloride channel expression and function in secretory epithelia. Investigators have also used NPD to demonstrate ion transport abnormalities in newborns with respiratory distress. Standard perfusates for diagnostic NPD studies include the use of amiloride, replacement of chloride with gluconate, cAMP agonists, and nucleotides such as ATP. The pH of these perfusates may also be relevant to NPD studies as we have previously shown that the respiratory epithelia in mammals express CLC-2, which is a pH sensitive chloride channel. We hypothesized that acidic pH might activate chloride secretion in vivo if CLC-2 is present in human respiratory epithelia. Our objective was to determine the effect of acidic pH on NPD measurements and the frequency of expression of CLC-2 in normal subjects. Healthy adults were recruited and CLC-2 protein expression was detected in 20 of 29 primary nasal epithelial cell cultures. Acidic pH stimulated NPD responses in 33% of subjects. These findings suggest that pH sensitive alternative pathways are available for modulation in human respiratory epithelia and that NPD protocols should standardize pH of perfusates.
Quantitative fractionation of serum bilirubin species by reversed-phase high-performance liquid chromatography

Abstract A rapid high-performance liquid chromatographic method is described for separating and quantifying four bilirubin species present in serum: bilirubin, bilirubin monoglucuronide, bilirubin diglucuronide, and bilialbumin. Sample preparation consists of dilution with ascorbic acid and dimethylsulfoxide and filtration to remove solid materials. The diluted serum was injected directly onto a wide-pore (300 A) reversed-phase column and the bilirubin species eluted with a water—isopropanol gradient. Excellent agreement was found between the total bilirubin concentration measured by the high-performance liquid chromatographic method and a diazotized sulfanilic acid procedure.
Spectral emissivities and integrated intensities of the 6·3-μ fundamental band of H2O

Abstract Spectral emissivities of thev2-fundamental band of water have been measured between 550° and 2200°K. The hot water vapor samples were produced in a small supersonic burner using H2 and O2 gases. The variation of the spectral emissivities of H2O as a function of temperature has been obtained for a constant amount of H2O in the optical path. An estimate of the integrated intensity of the 6·3-μ fundamental band has been made from the high temperature emission spectra. The observed integrated intensity of the 6·3-μ H2O band was 300±20 per cent (cm-2·atm-1) at 273°K and is independent of the temperature.
Energy intensities in ecological and economic systems

Abstract The concept of energy intensity (the energy needed, directly and indirectly, to effect the production of a “modity” an be applied to both economic and ecological systems. Hannon (1979) and Constanza (1980) have remarked on the lack of variation of energy intensity between different commodities for an ecosystem and an economic system, respectively. T This is particularly surprising for the ecosystem, since it seems to violate the traditional pyramid view of trophic systems. I show rigorously that Hannon's result is a mathematical consequence of his assumptions which are physically unjustified. I present a similar intuitive argument for Costanza's result, which is based on controversial but not physically unacceptable assumptions. The discussion brings out common threads of input-output economics and ecosystem analysis.
The reaction center and associated cytochromes of Thiocapsa pfennigii: Their thermodynamic and spectroscopic properties, and their possible location within the photosynthetic membrane

The majority of photosynthetic bacteria possess bacteriochlorophyll a, but two species, Rhodopseudomonas viridis and Thiocapsa pfennigii, possess bacteriochlorophyll b, which absorbs at significantly longer wavelengths. The reaction center of Rps. viridis has been extensively studied; this paper presents studies on the reaction center of T. pfennigii, with the following results. 1. (i) The “primary donor” bacteriochlorophyll dimer of T. pfennigii has a midpoint redox potential of +490 mV at pH 7, and the oxidized form has a gaussian EPR signal centered close to g = 2.0025 with a peak-to-peak width of 13 G. The zero field splitting characteristics of the light-induced triplet state of the bacteriochlorophyll dimer, seen when the “primary acceptor” is reduced before illumination, are D = 158 · 10−4 cm−1, E = 39 · 10−4 cm−1. These EPR properties are very similar to those of the bacteriochlorophyll dimer of Rps. viridis, and are quite distinct from those of bacteriochlorophyll a-containing species. 2. (ii) The intermediary carrier, I, which is probably a bacteriopheophytin b molecule in close association with the “primary acceptor”, can be trapped in its reduced form by the illumination of appropriately poised samples at 200 K. The EPR signals associated with I−· are very similar to those of Chromatium vinosum, with the majority of the spins being observed in the form of a broad signal centered close to g = 2.003, and split by 68 G; the magnitude of the splitting of this signal is only half that seen in Rps. viridis. We have been unable to measure the Em of the I/I−· couple in T. pfennigii. 3. (iii) The “primary acceptor” of T. pfennigii is very similar to that of the majority of other purple bacterial species, being characterized by an EPR signal at g = 1.82 and g = 1.62. The Em of the redox couple is pH-dependent below pH 6.5, and the Em of the unprotonated couple, which is believed to function in electron flow, is −130 mV. 4. (iv) Four cytochrome hemes can apparently donate electrons to the photooxidized bacteriochlorophyll dimer free radical cation, two of cytochrome c-555 (Em7 = 340 mV) and two of cytochrome c-550 (Em7 = 0). If all are reduced prior to illumination, the latter are preferentially oxidized. 5. (v) The carotenoid bandshift of T. pfennigii can be interpreted as indicating that the bacteriochlorophyll dimer is located near the middle of the membrane dielectric, with the high potential cytochrome c-555 closer to the inside, and quinone · iron closer to the outside of the chromatophore membrane. The low potential cytochrome c-550 seems to be nearer the outside of the membrane than the bacteriochlorophyll dimer.
Use of in vitro fertilization and embryo transfer to circumvent infertility caused by an inherited imperforate vagina in mice.

An autosomal recessive mutation (ipv) causing infertility in homozygous females (ipv/ipv) because of imperforate vaginae was discovered in a line of mice selected for low lean tissue mass as a proportion of body weight. The aim of this study was to determine if the mutation could be propagated in offspring following embryo transfer of oocytes collected from mutant females and fertilized in vitro with sperm from males known to carry the gene (ipv/?). Caudal epididymal sperm were incubated with cumulus-enclosed oocytes for 8–10 hr in tissue culture medium 199+5% fetal calf serum +0.4% bovine serum albumin. Oocytes possessing at least two pronuclei were transferred to recipient CD-1 females which had been mated 24 hr earlier to vasectomized males. A total of 683 oocytes was collected from 27 superovulated mutant females. A large proportion of the oocytes was abnormal as evidenced by cytoplasmic fragmentation (259/683, 38%). Seventy-eight percent (331/424) of the normal oocytes were fertilized and 181 of these were transferred to 10 recipients. Six of 10 recipients delivered 38 offspring (24 females, 14 males). Fifty-eight percent (14/24) of the female offspring displayed an imperforate vagina. The results demonstrate that in vitro fertilization and embryo transfer can be used for propagating a mutant gene that causes infertility in females.
A model of crossbridge action: the effects of ATP, ADP and Pi.

We have explored a model of crossbridge kinetics that explains many of the effects on steady-state muscle contraction of ligands that bind to the nucleotide site on myosin. The mathematical model follows the basic framework for crossbridge function first established by A. F. Huxley. In the model, detached crossbridges initially bind in a weakly Attached, A.M.D.Pi state (A, actin; M, myosin; D, ADP; Pi, orthophosphate) at the beginning of the region of positive force production. Pi release then results in transition to a strongly-bound A.M.D state, as has been suggested by other investigators from both biochemical and mechanical data. Mg2+ ADP release and subsequent crossbridge detachment due to Mg2+ ATP binding to the A.M state occur at the end of the region of positive force production. Work in a number of laboratories has now defined the effects on steady-state contraction of variations in the concentrations of Mg2+ ATP, Mg2+ ADP and Pi. These data provide valuable constraints that can be used to further refine current models. The maximum velocity of shortening (V max) and ATPase activity of muscle fibres exhibit classical saturation behaviour with respect to Mg2+ ATP concentration, with Mg2+ ADP acting as a competitive inhibitor. The model can reproduce this behaviour. The model also explains the observations that increasing [Mg2+ ATP] decreases isometric tension and increasing [Mg2+ ADP] increases tension. As the concentration of Pi increases, model predictions suggest that tension should decrease approximately as log[Pi], that ATPase activity should decrease less than tension and thatV max should be almost unchanged, as has been found experimentally. The model also demonstrates that the connection between the parameters of contraction and the free energy of hydrolysis of Mg2+ ATP can be complex.
Additive Manufacturing: Exploration of Porosity and Form Features Using Layer by Layer Deposition

Aerospace companies use high-strength metal alloys like Inconel or Titanium which could be very difficult to fabricate using conventional methods. The current manufacturing techniques result in significant waste. Additive Manufacturing (AM), in its current state is not sufficiently understood, nor characterized such that conventional design practices and process qualification methodologies can be used. In addition, AM cannot be considered for the manufacture of aircraft components unless the process is stable and controlled. The mechanical properties of fabricated parts require to be characterized to demonstrate their invariability. The laser deposition using complex geometries is a challenge. In addition, the structural performances of AM parts have to be proved. Inherent in these requirements is the need to develop a process specification which requires the monitoring and control of key raw materials, consumables, and process parameters; the development of a fixed practice for each of the AM process. Several procedures are required in order to understand how additive manufacturing works using advanced and complex design models. The ability to adopt AM to the production of components is not only predicated on the ability of AM to be competitive with conventional manufacturing methods in terms of cost, but also on its ability to deliver parts with repeatable mechanical performance. The objective of this paper is to define and characterize the limitation of various complex geometries using additive manufacturing. The experimental research involved the creation of a number of specimens using direct metal laser sintering process, examination of their form features, documenting DMLS geometry limits for the form features and finally the creation of calibration models that can be used in aerospace design manuals.Copyright © 2012 by ASME
Safety of the American Heart Association Step 1 Diet in Childhood

Can we totally answer the question of the safety of the American Heart Association Step 1 Diet in children over the age of 2 years? Available evidence certainly points to this diet as being safe and not harmful to growing children. A major concern of cholesterol-lowering diets is the misapplication of nutritional guidelines. However, this concern is not exclusive to cardiovascular related nutrition. Therefore, we feel confident that this diet can be implemented in the general population without any adverse effects on growth and development in North American children. It seems prudent to continually monitor children in different settings as is being currently evaluated in certain ongoing studies such as the Dietary Intervention Study in Children (DISC). The DISC program is monitoring children's growth, development, and nutritional status to insure no long-term adverse effects of Step 1 Diets. The focus of future strategies and investigations should be to identify effective methods for the dissemination of accurate nutritional information. Proper education via school programs, the various forms of media, and instructions from educated allied health professionals may all play a major role. It is essential that a variety of strategies be used to provide information and guidance to the general population and to families with children who have high blood cholesterol levels.
Mechanism of electron conduction in self-assembled alkanethiol monolayer devices.

A BSTRACT : Electron tunneling through self-assembled monolayers (SAMs) of alkanethiols was investigated using nanometer scale devices that allow temperature-dependent current‐voltage, I ( V , T ), measurements. The I ( V , T ) measurement results show, for the first time, temperature-independent electron transport characteristics, proving direct tunneling as the transport mechanism in alkanethiol SAMs. The measured tunneling currents can be fitted with theoretical calculations using the modified rectangular barrier model of
Analysis of Juniperus communis and its varieties based on DNA fingerprinting

Abstract Plants of Juniperus communis L. var. communis , J. c . var. depressa Pursh, J. c . var. hemispherica J. & C. Presl, J . communis var. megistocarpa Fern. & St. John, J. c . var. nipponica (Maxim.) Wils., J. c . var. oblonga hort. ex Loudon and J . c . var. saxatilis Pall. were sampled and DNA fingerprinting (RAPDs, Random Amplified Polymorphic DNAs) was performed. Based on 191 RAPD bands, there was little evidence to support the recognition of J. communis var. hemispherica , J. c . var. oblonga and J. c . var. nipponica . Juniperus communis var. communis (Sweden) was found to be most similar to J . c . var. hemispherica from Sicily, and also very similar to J. c. var. saxatilis . The recognition of J. c . var. saxatilis , sensu stricto, and var. hemispherica (from Sicily) was not supported by the RAPD data in this study. All of the J. c . var. depressa populations sampled from the Western Hemisphere formed a distinct group. Juniperus communis var. megistocarpa , endemic to maritime eastern Canada, was the most distinct variety of J. communis . Juniperus communis var. “ saxatilis ” populations from the Kamchatka peninsula and J . c . var. “ hemispherica ” from the Sierra Nevada, Spain, were very distinct from other J. c . var. communis – saxatilis populations.
Understanding leakage current susceptibility in dielectrics using molecular modeling

Dielectric materials are universally used in the fabrication and packaging of transistors in microelectronics and displays, as well as used in discrete devices such as sensors, switches and photovoltaics. However, as device and interconnect sizes become smaller, the question of the source of electrical failure becomes more and more important. During the development of these materials it has been found that small changes in the molecular structure can lead to small increases in conductivity which is undesirable for most applications. Although important to the final commercial acceptance of the dielectric, leakage current is often one of the final properties measured when developing the chemistry of the dielectric, so a dielectric with very good mechanical properties can ultimately fail at customer due to the electrical properties. Knowledge of the susceptibility for electrical failure can be a great aid to the developer.
Pathophysiology of hydrops fetalis

Hydrops fetalis occurs when the rate of interstitial fluid production by capillary ultrafiltration exceeds the rate of interstitial fluid return to the circulation via lymphatic vessels. Developmental differences in the microcirculation and lymphatic system of the fetus, as compared with mature subjects, renders the fetus susceptible to interstitial fluid accumulation. These differences include greater capillary permeability, more compliant interstitial compartment, and greater influence of venous pressures on lymphatic return. The balance between interstitial fluid production and removal is most commonly disrupted as a consequence of homeostatic mechanisms serving to preserve adequate systemic delivery of metabolic substrate when cardiocirculatory function is impaired. The pathophysiology of two conditions of impaired cardiocirculatory function, atrial tachycardia and severe anemia, serve as examples of the mechanisms by which these homeostatic mechanisms perturb the balance of interstitial fluid movement.
Ethical thought in public relations history: Seeking a relevant perspective

A serious retardant to development of a specifically public relations (PR) ethical philosophy is the tendency to retain a commitment uniquely journalistic— objectivity. Ivy Lee and Edward Bernays offered two ethical options or imperatives, based on objectivity or on advocacy. Public relations must accept a commitment to the ethics of persuasion in order to reduce a crippling inferiority complex and advance understanding of the profession by its practitioners as well as the public.
A Real Time Price Signal for FACTS Devices to Reduce Transmission Congestion

The challenge of operating the electric power system while not being able to directly control power flows on the transmission grid is exacerbated as industry restructuring substantially alters the use of the aging transmission system. This paper investigates the use of a proposed closed-loop price signal that integrates FACTS devices into the real time electricity market with the objective of decreasing congestion as needed in real time to facilitate scheduled power flows and improve the transfer capability of the high voltage grid. Dynamic models of the power system are developed, and simulation results demonstrate FACTS devices responding to nodal price and transmission constraint information. These results are intended to be useful to system operators as well as to policy makers and regulators interested in developing methods for transmission system operation that minimize congestion in order to allow scheduled power transactions to flow
Simple Equivalent Circuit Model of a Stripline in Inhomogeneous Dielectric Media

Equivalent circuit models of a stripline have been proposed previously but most of them are either in a very complex form or are only able to model striplines in homogeneous media. In this work, modal decomposition technique is applied and a simple equivalent circuit model for a stripline in inhomogeneous substrate is proposed. Comparison with other models is also presented.
Toward a total synthesis of the stemofoline alkaloids: advancement of a 1,3-dipolar cycloaddition strategy

Novel, intramolecular 1,3-dipolar cycloadditions of azomethine ylides have been applied to the synthesis of functionalized core structures of the stemofoline alkaloids. In an effort to maximize the efficiency of this key transformation in the context of an eventual total synthesis of these complex natural products, a number of strategic modifications to the cycloaddition substrate were investigated. The collective efforts have provided useful insights into the operative, regiochemical control elements for 1,3-dipolar cycloadditions leading to stemofoline alkaloids. A potential intermediate in the synthesis of these alkaloids was prepared.
Integrating Ecological Momentary Assessment and Functional Brain Imaging Methods: New Avenues for Studying and Treating Tobacco Dependence

introduction: Ecological momentary assessment (EMA) and related methods typically entail repeatedly and intensively sampling behavior as it occurs over time and under naturalistic conditions. Although the methodological features of EMA make it a highly valuable research technique in its own right, EMA can also be a potent counterpart to other approaches. One methodological partnership with substantial yet largely untapped potential for the study of tobacco dependence is the pairing of EMA with functional brain imaging. Methods: The goal of this review is to outline the promise of this approach, with a focus on the combined use of EMA and functional magnetic resonance imaging (fMRI). Due to the unique and complementary strengths of each method, the merger of EMA and fMRI methods has the potential to advance the understanding of tobacco dependence in ways difficult or impossible to achieve through the use of either method in isolation. Results: In addition to describing a conceptual basis for combining EMA with fMRI, we provide a preliminary empirical illustration of this integrative approach using data from an ongoing study. conclusions: EMA and fMRI have independently yielded important findings regarding the nature and treatment of tobacco dependence. The integration of these powerful research methods, however, holds even greater potential for the field of tobacco research. Additionally, recent advances are paving the way for the synergistic use of fMRI and EMA-based methods to develop innovative approaches to tobacco cessation.
Structure of the Disulfide Bond Generating Membrane Protein DsbB in the Lipid Bilayer

The integral membrane protein DsbB in Escherichia coli is responsible for oxidizing the periplasmic protein DsbA, which forms disulfide bonds in substrate proteins. We have developed a high-resolution structural model by combining experimental X-ray and solid-state NMR with molecular dynamics (MD) simulations. We embedded the high-resolution DsbB structure, derived from the joint calculation with X-ray reflections and solid-state NMR restraints, into the lipid bilayer and performed MD simulations to provide a mechanistic view of DsbB function in the membrane. Further, we revealed the membrane topology of DsbB by selective proton spin diffusion experiments, which directly probe the correlations of DsbB with water and lipid acyl chains. NMR data also support the model of a flexible periplasmic loop and an interhelical hydrogen bond between Glu26 and Tyr153.