cssi/SciSciGPT-SciSciNet huggingface dataset:
Functional Expression of Recombinant Spiny Dogfish Shark (Squalus acanthias) Cytochrome P450c17 (17α-Hydroxylase/C17,20-lyase) in Yeast (Pichia pastoris)

The cDNA encoding the spiny dogfish shark (Squalus acanthias) testicular form of cytochrome P450c17 (CYP17) was used to direct the heterologous expression of a functional enzyme in yeast (Pichia pastoris). This protein possesses two enzymatic activities: 17 alpha-hydroxylase and C17,20-lyase reactions. Cytochrome P450c17 is a key steroidogenic enzyme for the production of sex steroids in gonadal tissue and for cortisol production in adrenal tissue. This study describes the culture conditions and the enzymatic activity of recombinant shark cytochrome P450c17. The shark enzyme was compatible with the endogenous yeast NADPH-cytochrome P450 reductase and was bioactive within the living yeast cell. Progesterone (at 15 microM) was metabolized (51 pmol/min/10(9) cells) faster than pregnenolone (36 pmol/min/10(9) cells). Both progesterone and pregnenolone were completely metabolized to their respective androgens (androstenedione and dehydroepiandrosterone). Although 11 beta-hydroxy-progesterone was readily 17 alpha-hydroxylated by the shark P450, the lyase reaction was not evident. Alterations to the 2-carbon sidechain of progesterone (21-hydroxylation or 20 beta-reduction) prevented metabolism. High-density cultures (> 1.5 x 10(9) cells/ml) yielded the greatest quantity of recombinant protein but cultures of lower density produced more recombinant protein per cell. This is the first report of heterologous expression in yeast of a steroidogenic cytochrome P450 from a lower vertebrate.
Real-time bio-sensors for enhanced C2ISR operator performance

The objectives of two Air Force Small Business research topics were to develop a real-time, unobtrusive, biological sensing and monitoring technology for evaluating cognitive readiness in command and control environments (i.e., console operators). We sought an individualized status monitoring system for command and control operators and teams. The system was to consist of a collection of bio-sensing technologies and processing and feedback algorithms that could eventually guide the effective incorporation of fatigue-adaptive workload interventions into weapon systems to mitigate episodes of cognitive overload and lapses in operator attention that often result in missed signals and catastrophic failures. Contractors set about determining what electro-physiological and other indicators of compromised operator states are most amenable for unobtrusive monitoring of psychophysiological and warfighter performance data. They proposed multi-sensor platforms of bio-sensing technologies for development. The sensors will be continuously-wearable or off-body and will not require complicated or uncomfortable preparation. A general overview of the proposed approaches and of progress toward the objective is presented.
Graduate Statistics Service Courses

Abstract This article describes our experience in, and recommendations for, teaching introductory statistics service courses to graduate students. Drawing on the student's research orientation, the instructor can present statistics as a valuable component of the scientific method, using examples from the student's particular discipline(s). Statistically qualified course instructors may be affiliated with statistics or other departments, and the course may be offered within any department. Course goals can range from training students to function independently as statistical analysts in future research to training students to consult a qualified statistician about design and analysis issues.
Performance analysis of photovoltaic thermal air heaters

The performance of single-pass and double-pass combined photovoltaic thermal collectors are analyzed with steady-state models. The working fluid is air and the models are based on energy conservation at various nodes of the collector. Closed form solutions have been obtained for the differential equations of both the single-pass and double-pass collectors. Comparisons are made between the performances of the two types of combined photovoltaic thermal collectors. The results show that the new design, the double-pass photovoltaic thermal collector, has superior performance. Important parameters for both types of collector are identified, and their effects on the performances of the two types of collectors are presented in detail.
The pure rotational Raman spectra of 1,4-cyclohexadiene and 1,3,5-cycloheptatriene☆

Abstract The pure rotational Raman spectra of 1,4-cyclohexadiene and 1,3,5-cycloheptatriene were photographed with a plane grating spectrograph in the thirteenth order of a 300 groove/mm blazed grating. The spectra resemble those of symmetric top rotors with well-developed R- and S-branches. The molecular constants were found to be B 0 = 1 2 (A 0 + B 0 ) = 0.1671 1 ± 0.00006 cm −1 and DJ = (2.1 ± 0.4) × 10−8 cm−1 for 1,4-cyclohexadiene and B 0 = 1 2 (A 0 + B 0 ) = 0.1226 4 ± 0.00005 cm −1 and DJ = (1.4 ± 0.5) × 10−8 cm−1 for 1,3,5-cycloheptatriene. The results of this study lend support to the molecular structures that have been derived on the basis of infrared and Raman vibrational spectra.
The gravity model, African Growth and Opportunity Act (AGOA) and US trade relations with sub-Saharan Africa

The United States of America enacted the African Growth and Opportunity Act (AGOA) in 2000 to grant sub-Saharan African countries (SSA) a preferential treatment in their exports to the USA. With this Act, most of the exports from SSA can now enter the USA duty-free, and this is expected to boost the exporting and manufacturing sectors in SSA. Hopefully, this singular act of assistance from the USA will spur entrepreneurship in SSA, thereby creating jobs and jump starting meaningful economic growth in the region. Since trade is a major catalyst in economic development, AGOA is arguably the most meaningful intervention from a developed country to an under-developed region such as SSA in recent times. Has AGOA had any impact on US trade with SSA? This paper sheds some light on this issue by examining the flow and composition of trade between the USA and AGOA countries. The analysis uses trade data (US imports) for 36 countries over 12 years. Empirical estimations based on the gravity model show that receivin...
Transmission-constrained unit commitment based on Benders decomposition

An efficient algorithm based on Benders decomposition is proposed for dealing with the transmission-constrained unit commitment problem. Using Benders decomposition, the formulation of the unit commitment with transmission constraints is decomposed into a master problem and a subproblem. The master problem solves unit commitment without transmission constraints by augmented Lagrangian relaxation and the subproblem minimizes violations of transmission constraints by adjusting unit generation and phase shifter controls and testing the feasibility of the unit commitment schedule. In the case of infeasibility in transmission flows, a proper constraint (Benders cut) is introduced for unit commitment rescheduling based on violations in the subproblem. The iterative process between the master problem and the subproblem provides a minimum production cost solution for generation scheduling while satisfying transmission constraints. A modified IEEE-30 bus system is presented to demonstrate the efficiency of the method.
Reduced storage matrix methods in stiff ODE systems

Stiff initial-value ODE methods (e.g. BDF) normally require the Jacobian matrix as part of a Newton-like iteration within each implicit time step, and require it to be formed and stored explicitly, whether the linear algebraic method used is direct or iterative. But, a Krylov subspace iterative linear system method, which involves the system matrix only in operator form, can be made part of an inexact Newton method within such a stiff ODE method in a matrix-free manner, requiring no explicit Jacobian matrix storage. Such combinations, using BDF methods, have been implemented with Arnoldi iteration, GMRES (the Generalized Minimum RESidual method), and CG (the Conjugate Gradient Method). Various practical matters (scaling, starting, stopping, etc.) are dealt with in the stiff ODE context. In the context of general nonlinear algebraic systems, we provide some theoretical foundation for the combined Newton-Krylov method by giving convergence results that include errors due to the difference quotient approximation to the linear operator. Earlier tests showed matrix-free methods to be quite effective, at least when the spectrum of the kproblem Jacobian is rather tightly clustered. To improve their robustness, we have added preconditioning, in an experimental solver called LSODPK, which we tested on ODE systems that arise from time-dependent PDE systems by the method of lines. Preconditioner matrices can be formed from the interaction or reaction terms, from the spatial transport terms, or both (as in operator splitting). The additional matrix storage can be reduced greatly by grouping the diagonal blocks in a natural way. The methods appear to be quite effective in improving both speed and storage economy over traditional stiff methods, and over matrix-free methods without preconditioning.
Nonthermal Plasma Synthesis of Faceted Germanium Nanocrystals

Low-pressure plasmas are known for their ability to synthesize nanoparticles via gas-phase nucleation. While in the past this particle formation has often been considered from the viewpoint of a contamination problem in semiconductor processing, we here describe a low-pressure plasma that enables the synthesis of faceted germanium nanocrystals. The germanium nanocrystals are generally single crystals without any planar defects such as twin boundaries. A change in the morphology with particle size is observed. Small germanium particles up to about 30 nm in size are mostly cubes with (100) crystal facets. Larger crystals between 30–60 nm are primarily cuboctahedrons. Even larger nanocrystals are mainly spherical. The shape evolution is interpreted in terms of the equilibrium shape of hydrogen-coated germanium crystals. Possible applications of these crystals are discussed.
LEYDIG CELL TUMOR PRESENTING AS CONGENITAL ADRENAL HYPERPLASIA (CAH)

Sexual precocity and a testicular mass can result from a Leydig cell tumor or from simple virilizing CAH with adrenal rests in the testes. These diagnoses are usually distinguished by very high plasma 17-hydroxyprogesterone (170HP) in CAH. However, 170HP from adrenal rests may not be suppressible with glucocorticoids, and these entities may not be distinguishable pathologically. A 3 6/12 y.o. boy had a 2-3 month history of rapid growth and phallic enlargement. The left testis was 1.0 cm and the right was about 1.7 cm long, obscured by a hydrocele. Bone age was 7 yr, testosterone (T) 498 ng/dl, and 170HP 3340 ng/dl, suggesting CAH. Glucocorticoid treatment failed to suppress 170HP and T, and virilization progressed. At 3 9/12 y.o. the 170HP was 7409, the T was 548, and the right testis had grown to about 2.7 cm. An LRF test was prepubertal and an ACTH test showed no significant rise in the elevated basal 170HP, androstenedione or 21-deoxycortisol. Ultrasonography and magnetic resonance scanning revealed a mass replacing the right testis, shown at surgery to be a 2.0 cm Leydig cell tumor. The tumor contained mRNA for P450sec (the cholesterol side-chain cleavage enzyme) and P450c17 (17 α-hydroxylase/17, 20 lyase), but no detectable mRNA for P450c21 (21-hydroxylase), as is typical of testicular tissue but not adrenal tissue. The post-op 170HP and T were normal before and after ACTH. This case illustrates that Leydig cell tumors and non-suppressible adrenal rests in CAH may be hormonally indistinguishable preoperatively.
Cost consequences of surveillance, medical management or surgery for benign prostatic hyperplasia.

AbstractPurpose: The cost consequences of alternative treatment modalities for benign prostatic hyperplasia (BPH) were investigated. The present lifetime costs of watchful waiting, medical management and surgery alone and in various combinations were estimated for a synthetic cohort of men comprised of 5 age groupings.Materials and Methods: Synthetic cohort models were constructed to follow men at different ages “analytically” for specific intervals and to calculate the cumulative health care costs associated with alternative BPH treatment regimens during those periods. These models accounted explicitly for survival probabilities, the use of different types of health care services and products, price changes for those services and products, failure rates of some therapies and a discount factor needed to compute the present value of the cost streams. The models were implemented with hospital discharge and other data on BPH incident cases in the state of Florida in approximately 1989.Results: The addition o...
Excellence, School Culture, and Lessons in Futility: Another Case against Simplistic Views of Educational Change.

(1986). Excellence, school culture, and lessons in futility: another case against simplistic views of educational change. Journal of Curriculum Studies: Vol. 18, No. 1, pp. 31-43.
A. M. Quennell Father of Transform Faults and Poles of Rotation

In the 1940s and 1950s, A. M. Quennell (1906–1985) was using, in a very practical way, many of the concepts of plate tectonics which were to become so important in the 1960s and 1970s. He spent most of his working life in the Middle East and Africa and made the Dead Sea Rift his special study. In his first major publication on the geology and mineral resources of former Trans-Jordan in 1951, he came down firmly in favor of the views originally proposed by Lartet [1869] that the Dead Sea Rift is due to shear and the Red Sea to drift, the shear zone being the boundary between the “Palestine block” (Sinai plate) and the “Arabia block” (Arabian plate).
Novel theory and algorithm for fuzzy distance transform and its applications

This paper describes the theory and algorithms of fuzzy distance transform (FDT). Fuzzy distance is defined as the length of the shortest path between two points. The length of a path in a fuzzy subset is defined as the integration of fuzzy membership values of the points along the path. The shortest path between two points is the one with the minimum length among all (infinitely many) paths between the two points. It is demonstrated that, unlike in the binary case, the shortest path in a fuzzy subset is not necessarily a straight-line segment. The support of a fuzzy subset is the set of points with nonzero membership values. It is shown that, for any fuzzy subset, fuzzy distance is a metric for the interior of its support. FDT is defined as the process on a fuzzy subset that assigns at each point the smallest fuzzy distance from the boundary of the support. The theoretical framework of FDT in continuous space is extended to digital spaces and a dynamic programming-based algorithm is presented for its computation. Several potential medical imaging applications are presented including the quantification of blood vessels and trabecular bone thickness in the regime of limited special resolution.
Subcallosal brain structure: correlation with hearing threshold at supra-clinical frequencies (>8 kHz), but not with tinnitus.

This study tested for differences in brain structure between tinnitus and control subjects, focusing on a subcallosal brain region where striking differences have been inconsistently found previously. Voxel-based morphometry (VBM) was used to compare structural MRIs of tinnitus subjects and non-tinnitus controls. Audiograms of all subjects were normal or near-normal at standard clinical frequencies (≤8 kHz). Mean threshold through 14 kHz, age, sex and handedness were matched between groups. There were no definitive differences between tinnitus and control groups in modulated or unmodulated maps of gray matter (GM) probability (i.e., GM volume and concentration, respectively). However, when the image data were tested for correlations with parameters that were either not measured or not matched between the tinnitus and control groups of previous studies, a notable correlation was found: Threshold at supra-clinical frequencies (above 8 kHz) was negatively correlated with modulated GM probability in ventral posterior cingulate cortex, dorsomedial prefrontal cortex, and a subcallosal region that included ventromedial prefrontal cortex and coincided with previously-reported differences between tinnitus and control subjects. The results suggest an explanation for the discrepant findings in subcallosal brain: threshold at supra-clinical frequencies may have differed systematically between tinnitus and control groups in some studies but not others. The observed correlation between (1) brain structure in regions engaged in cognitive and attentional processes and (2) hearing sensitivity at frequencies generally considered unnecessary for normal human auditory behavior is surprising and worthy of follow up.
Liposome encapsulation circumvents the hepatic clearance mechanisms of all-trans-retinoic acid.

All-trans-retinoic acid (ATRA) has been proven active against a range of malignancies in isolated tissue culture systems and in human clinical trials, but the duration of its effects has been transient. Recent evidence indicates that the basis for the limited duration of ATRA's activity, at least in one form of leukemia, is a pharmacological adaptation that results in reduced serum concentration after prolonged treatment. This finding suggests that an i.v. formulation of ATRA may significantly improve the potency and duration of ATRA's activity in leukemia and, potentially, other malignancies as well. Liposomal ATRA (L-ATRA) was developed to provide a formulation of this retinoic acid isomer that can be administered intravenously to provide potential pharmacological advantages over the oral formulation. When L-ATRA was administered to rats over a prolonged period, the blood levels of the drug did not change over time. In vitro studies of isolated liver microsomes revealed that catabolism of the drug was not altered in rats that were repeatedly administered the L-ATRA formulation. Whereas microsomes isolated from animals that were orally administered free ATRA the same number of times with the same doses showed a significant increase in metabolism of the drug. These results suggest that an i.v. formulation of ATRA such as L-ATRA could be extremely useful in inducing long-term remissions in patients with APL.
Some comments on neighborhood size for tessellation automata

The simplest possible neighborhood interconnection patterns that can be constructed from both partition and cover blocking preserving behavioral isomorphism are established for a broad class of two-dimensional arrays.
Possible upper limit to the distance of BL Lacertae.

BL LAC (VRO 42.22.01) is a strange source of radio, infrared and visual radiation. The radio spectrum has been investigated1 and rapid variations of radio frequency radiation have been found2–5. The continuum at visual and near infrared wavelengths has been described6,7 and the optical continuum is markedly polarized6. Rapid variations of the visual radiation on time scales as short as 1 day have recently been reported8.
Metabolism of isopropyl carbanilate (propham) in alfalfa grown in nutrient solution

Abstract Alfalfa plants, Moapa variety, were grown in nutrient solution containing isopropylring-[14C] carbanilate (43.8 μCi/liter propham). After 8 days, 41.2% of the radioactivity initially added to the nutrient culture was recovered; 10.9% of this was from shoots, 3.4% from roots and 26.9% from nutrient medium. Nonextracted residues accounted for 23% of the radioactivity in shoots and 62% of that in roots. The parent herbicide constituted 53 and 38% of the radioactivity extracted from shoots and roots, respectively. The balance of extracted 14C was polar metabolites which were purified and subjected to enzymatic and acid hydrolysis. Four aglycones were isolated, three of which were purified by thin-layer chromatography and characterized by mass spectrometry. The principal aglycones were: isopropyl-2-hydroxycarbanilate, isopropyl-4-hydroxycarbanilate, and 1-hydroxy-2-propylcarbanilate. The fourth aglycone was not identified.
The effects of dietary selenium on the biotransformation of 7,12-dimethylbenz[a]anthracene

Abstract The influence of dietary selenium on the mutagenic activation of 7,12-dimethylbenz[ a ]anthracene (DMBA) by rat liver S9 was studied using the Ames test. Rats received supplemental selenium, as sodium selenite, in the drinking water or in the diet. All rats additionally received 0, 20, 50, 100, or 500 mg Aroclor 1254 per kg body weight. Revertant counts decreased 72 and 31% at the 20- and 100-mg/kg induction levels, respectively, with S9 preparations from rats given selenium supplementation, compared to controls. No significant effect of selenium on S9 preparations was observed in rats treated with 500 mg/kg Aroclor. Preparations of S9 from rats receiving 2.5 ppm Se in their diet produced 46, 84 and 70% less revertants than controls at the 20-, 50- and 100-mg/kg induction levels. Increasing the selenium concentration in the diet to 5 ppm reduced the revertant counts by 71, 68 and 65%, at the 20-, 50- and 100-mg/kg induction level of Aroclor, respectively. Dietary selenium supplementation was shown to decrease the mutagenic activation of DMBA by liver microsomes. These studies indicate that in vivo selenium supplementation may reduce susceptibility to the action of various carcinogens.
Mean Wiener numbers and other mean extensions for alkane trees

The “Wiener number” (the sum over intersite graph distances of a structure) as averaged over all alkane structural isomers of a fixed number N of carbon atoms is considered. This and several other measures of average graphical “extension” of N-site alkanes are computed for N up to 90 (where there are over 1035 such isomers). Fits are then made for several surmised or derived asymptotic forms, and a heuristic argument is made relating these results to geometric extensions of a random mix of (N-site) alkanes.
A 100GHz active-varactor VCO and a bi-directionally injection-locked loop in 65nm CMOS

A 100GHz fundamental active-varactor VCO and a bi-directionally injection-locked loop are demonstrated in 65nm CMOS. Without using a conventional passive varactor, the proposed VCO achieves a tuning range of 5.2% at 100GHz and a phase noise of -112.1dBc/Hz at 10MHz offset. By utilizing the proposed transmission-line-based capacitive coupling, four oscillators are injection-locked properly and the loop creates eight phases of the carrier and 6dB(=10log4) of phase noise improvement, realizing a measured phase noise is -118.8dBc/Hz at 10MHz offset.
Iatrogenic Hypophosphatemia in Infants ith Renal Insufficiency

The brief report of W. F. Dodge and L. B. Travis concerning "Iatrogenic Hypophosphatemia in Infants with Renal Insufficiency" (Pediatrics, 35: 792, 1965) prompts me to air my doubts in "A Letter to the Editor" about the value of restriction of phosphate intake as a means of treatment for hypocalcemia and hyperphosphatemia encountered in infants with renal insufficiency. The difficulties posed by decreased renal capacity for phosphate clearance in renal insufficiency are well recognized. The importance of deficient intestinal absorption of calcium in renal insufficiency is, however, often overlooked.
What Fame Is: Bukowski's Exploration of Self

Although this quote reads like a description of Hollywood and its celluloid environs, the author is reviewing Run With the Hunted: A. Charles Bukowski Reader, a comprehensive anthology of the poet-novelist's work. From Flower, Fist and Bestial Wail (1960), his first full-length collection of poetry, to Pulp, published shortly after his death in 1994, Bukowski chronicled the humorous, lyric, impoverished lives of prostitutes, drinkers, bums, writers, and miscreants of every description. His tales of squalor which document the starving and passionate Angeleno writer are in large measure inspired by John Fante.Los Angeles is Buk territory. He lived in and wrote about Central Los Angeles for most of his seventy-three years. L.A. is a place where, in the realm beyond fiction, people migrate in pursuit of dreams. One category of migrant dream-seeker is the writer. Whether he/she is a neophyte seeking fortune as a screenwriter or an aging, established author reviving an endangered career, the writer confronts an industry whose interests and intents are tangential to his/her own.
The origins of age-related proinflammatory state

We hypothesized that the rising levels of inflammatory markers with aging is explained by cardiovascular risk factors and morbidity becoming progressively more prevalent in older persons. Information on inflammatory markers, cardiovascular risk factors, and diseases was collected in 595 men and 748 women sampled from the general population (age, 20-102 years). In both men and women, older age was associated with higher levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1ra), IL-18, C-reactive protein (CRP), and fibrinogen, while soluble IL-6 receptor (sIL-6r) increased significantly with age only in men. Adjusting for cardiovascular risk factors and morbidity, the age regression coefficients became substantially smaller in models predicting IL-6, IL-1ra, IL-18, and fibrinogen and larger in the model predicting sIL6r. Adjustment for cardiovascular morbidity substantially reduced the effect of age on CRP in men but not in women. Findings were confirmed in a subgroup of 51 men and 45 women with low risk profile and no cardiovascular morbidity. Part of the “proinflammatory state” in older persons is related to the high prevalence of cardiovascular risk factor and morbidity.
A critical role for increased labile zinc in reducing sensitivity of cultured sheep pulmonary artery endothelial cells to LPS-induced apoptosis.

We previously noted an important signaling role for decreased labile intracellular zinc ([ Zn ] i) in LPS-induced apoptosis in cultured sheep pulmonary artery endothelial cells (SPAEC) (Tang ZL, Wa...
Cephalosporin-resistant pneumococcal pneumonia: does it, affect outcome?

Abstract Study Objectives: Penicillin resistance has been reported in various studies to have no impact on the outcome of pneumococcal pneumonia. However, the importance of cephalosporin resistance has not been systematically studied. We conducted an analysis of patients with high-level cephalosporin-resistant Streptococcus pneumoniae pneumonia (H-CRSPP)– Design: Retrospective matched, case–control study. Setting: Two inner-city academic hospitals. Patients: Twenty-six patients with H-CRSPP admitted to the hospital between 1995 and 1999 were identified. Each patient was matched with two controls with cephalosporin-sensitive but oxacillin-resistant pneumococcal pneumonia admitted during the same time period. Matching was done based on pneumonia severity of illness index (PSI) and for other factors. Interventions: None. Measurements and Results: We evaluated a number of outcomes including mortality, length of stay in the hospital, and time to respond to treatment. Patients with H-CRSPP took longer to respond to treatment (6.5±0.9 days vs 4.1±0.7 days, P =0.05) and had a longer length of stay in hospital (15.4±2.2 days vs 9.2±1.6 days, P =0.02), None of the other outcomes were different between the two groups. Conclusions: Overall, we have found that the presence of cephalosporin resistance does impact the course of pneumococcal pneumonia.
The Wisdom Development Scale: Further Validity Investigations.

Researchers are gaining an interest in the concept of wisdom, a more holistic yet often ineffable educational outcome. Models of wisdom abound, but few have rigorously tested measures. This study looks at Brown's (2004a, 2004b) Model of Wisdom Development and its associated measure, the Wisdom Development Scale (WDS; Brown & Greene, 2006). The construct validity, measurement invariance, criterion validity, and reliability of scores from the WDS were assessed with over 3000 participants from two separate groups: one a sample of professionals and the other a sample of college students. Support for construct validity and reliability with these samples was found, along with measurement invariance. Latent means analyses showed predicted discrimination between the groups, and criterion validity evidence, with another measure of collegiate educational outcomes, was found.
Race/Ethnicity, Religious Involvement, and Domestic Violence

The authors explored the relationship between religious involvement and intimate partner violence by analyzing data from the first wave of the National Survey of Families and Households. They found that: (a) religious involvement is correlated with reduced levels of domestic violence; (b) levels of domestic violence vary by race/ethnicity; (c) the effects of religious involvement on domestic violence vary by race/ethnicity; and (d) religious involvement, specifically church attendance, protects against domestic violence, and this protective effect is stronger for African American men and women and for Hispanic men, groups that, for a variety of reasons, experience elevated risk for this type of violence.
Radio frequency fingerprinting commercial communication devices to enhance electronic security

There is a current shift toward protecting against unauthorised network access at the open systems interconnection physical layer by exploiting radio frequency characteristics that are difficult to mimic. This work addresses the use of RF 'fingerprints' to uniquely identify emissions from commercial devices. The goal is to exploit inherent signal features using a four step process that includes: 1. feature generation, 2. transient detection, 3. fingerprint extraction and 4. classification. Reliable transient detection is perhaps the most important step and is addressed here using a variance trajectory approach. Following transient detection, two fingerprinting and classification methods are considered, including 1. power spectral density (PSD) fingerprints with spectral correlation and 2. statistical fingerprints with multiple discriminant analysis-maximum likelihood (MDA-ML) classification. Each of these methods is evaluated using the 802.11a orthogonal frequency-division multiplexing (OFDM) signal. For minimal transient detection error, results show that amplitude-based detection is most effective for 802.11a OFDM signals. It is shown that MDA-ML classification provides approximately 8.5-9.0% better classification performance than spectral correlation over a range of analysis signal-to-noise ratios (SNRA) using three hardware devices from two manufacturers. Overall, greater than 80% classification accuracy is achieved for spectral correlation at SNRA > 6 dB and for MDA-ML classification at SNRA > -3 dB.
Resveratrol Preconditioning Induces a Novel Extended Window of Ischemic Tolerance in the Mouse Brain

Background and Purpose—Prophylactic treatments that afford neuroprotection against stroke may emerge from the field of preconditioning. Resveratrol mimics ischemic preconditioning, reducing ischemic brain injury when administered 2 days before global ischemia in rats. This protection is linked to silent information regulator 2 homologue 1 (Sirt1) and enhanced mitochondrial function possibly through its repression of uncoupling protein 2. Brain-derived neurotrophic factor (BDNF) is another neuroprotective protein associated with Sirt1. In this study, we sought to identify the conditions of resveratrol preconditioning (RPC) that most robustly induce neuroprotection against focal ischemia in mice. Methods—We tested 4 different RPC paradigms against a middle cerebral artery occlusion model of stroke. Infarct volume and neurological score were calculated 24 hours after middle cerebral artery occlusion. Sirt1-chromatin binding was evaluated by ChIP-qPCR. Percoll gradients were used to isolate synaptic fractions...
Lineage tracing with Axin2 reveals distinct developmental and adult populations of Wnt/β-catenin–responsive neural stem cells

Since the discovery of neural stem cells in the mammalian brain, there has been significant interest in understanding their contribution to tissue homeostasis at both the cellular and molecular level. Wnt/β-catenin signaling is crucial for development of the central nervous system and has been implicated in stem cell maintenance in multiple tissues. Based on this, we hypothesized that the Wnt pathway likely controls neural stem cell maintenance and differentiation along the entire developmental continuum. To test this, we performed lineage tracing experiments using the recently developed tamoxifen-inducible Cre at Axin2 mouse strain to follow the developmental fate of Wnt/β-catenin–responsive cells in both the embryonic and postnatal mouse brain. From as early as embryonic day 8.5 onwards, Axin2+ cells can give rise to spatially and functionally restricted populations of adult neural stem cells in the subventricular zone. Similarly, progeny from Axin2+ cells labeled from E12.5 contribute to both the subventricular zone and the dentate gyrus of the hippocampus. Labeling in the postnatal brain, in turn, demonstrates the persistence of long-lived, Wnt/β-catenin–responsive stem cells in both of these sites. These results demonstrate the continued importance of Wnt/β-catenin signaling for neural stem and progenitor cell formation and function throughout developmental time.
The role of the immune system in the insulin resistance syndrome.

The complex relationship between immunity and the insulin resistance syndrome is likely mediated to a significant degree by cytokines and the inflammatory proteins they induce. Epidemiologic work has revealed associations between cytokines and clinically evident insulin resistance, and mechanistic studies have yielded insight into the induction of insulin resistance at the cellular level by cytokines such as tumor necrosis factor-α. Genetic polymorphisms significantly influence this relationship, and variations in cellular immunity as manifested by T-helper cell phenotype are likely to be important as well. Further elucidation of the link between immunity and insulin resistance may lead to more effective treatment, and potentially prevention, of the insulin resistance syndrome.
Phase transformations in low-alloy steel laser deposits

We examined the microstructure evolution in medium-carbon low-alloy steel upon laser engineering net shape (LENS) (LENS is a trademark of Sandia National Laboratories and the US Department of Energy, Albuquerque, NM). Involved was the deposition of 14 superimposed fine layers. Several characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), nanoindentation and electron back scattered diffraction (EBSD) were used in conjunction with three-dimensional finite element thermal modeling to rationalize the transformation mechanisms. Delta ferrite was the primary phase to solidify from the melt. Solid-state austenitisation led to allotriomorphic hexagonal prisms that grew following a unique direction depending upon the parent delta-grain crystallographic orientation. A supersaturated lower bainitic plate was the main phase to have transformed from austenite, except for the first two deposited layers where martensite predominated. The supersaturated plate underwent a sudden-tempering reaction at the 10th layer but was confined at the plate boundaries. This tempering reaction became more transgranular and increasingly affected retained austenite and microphases for the underlying layers. Coalescence of carbon-depleted ferrite plates gave rise to the steady-stage microstructure at the fourth layer. This complicated microstructural evolution corroborated the microhardness fluctuations through all deposited layers.
Achieving robust human-computer communication

This paper describes a computational approach to robust human?computer interaction. The approach relies on an explicit, declarative representation of the content and structure of the interaction that a computer system builds over the course of the interaction. In this paper, we will show how this representation allows the system to recognize and repair misunderstandings between the human and the computer. We demonstrate the utility of the representations by showing how they facilitate the repair process.
An unsupervised Gaussian cluster formation technique as a Bussgang blind deconvolution algorithm

A decision-directed-type blind equalization algorithm is reformulated. It is based on the unsupervised Gaussian cluster formation technique. It is shown that the end result is closely related to the Bussgang algorithm and its implementation simplicity compares to the Bussgang blind deconvolution algorithm. It is also shown that along with the new algorithm, popular algorithms such as the Sato, Godard, maximum-level-error (MLE), and Bussgang blind equalization algorithms can all be categorized as decision-directed-type blind equalization algorithms which use a nonlinear estimator at the output of the equalizer to generate a decision-directed estimated error. >
Loading and Release Mechanism of Red Clover Necrotic Mosaic Virus Derived Plant Viral Nanoparticles for Drug Delivery of Doxorubicin

Loading and release mechanisms of Red clover necrotic mosaicvirus (RCNMV) derived plant viral nanoparticle (PVN) are shown for controlled delivery of the anticancer drug, doxorubicin (Dox). Previous studies demonstrate that RCNMV's structure and unique response to divalent cation depletion and re-addition enables Dox infusion to the viral capsid through a pore formation mechanism. However, by controlling the net charge of RCNMV outer surface and accessibility of RCNMV interior cavity, tunable release of PVN is possible via manipulation of the Dox loading capacity and binding locations (external surface-binding or internal capsid-encapsulation) with the RCNMV capsid. Bimodal release kinetics is achieved via a rapid release of surface-Dox followed by a slow release of encapsulated Dox. Moreover, the rate of Dox release and the amount of released Dox increases with an increase in environmental pH or a decrease in concentration of divalent cations. This pH-responsive Dox release from PVN is controlled by Fickian diffusion kinetics where the release rate is dependent on the location of the bound or loaded active molecule. In summary, controllable release of Dox-loaded PVNs is imparted by 1) formulation conditions and 2) driven by the capsid's pH- and ion- responsive functions in a given environment.
Diabetes and endometrial cancer in the Iowa Women's Health Study

Diabetes has been associated with increased risk of endometrial cancer in some epidemiological studies. Body mass index (BMI) and other measures of obesity have been associated positively with both diabetes and endometrial cancer. It is not clear whether or not the association of diabetes with endometrial cancer is explained entirely by obesity. Thus, we sought to test the hypothesis that diabetes is not associated with endometrial cancer independent of obesity. We examined the association between self-reported diabetes (onset at >30 years of age) and incident endometrial cancer in a prospective cohort study of 24,664 postmenopausal women in Iowa. Over 12 years of follow-up, 346 cases occurred among the cohort at risk. Data were analyzed using proportional hazards regression models. Diabetes was analyzed as reported at baseline and as a time-dependent variable using information obtained during follow-up. After adjustment for BMI, waist:hip ratio, and other covariates, the relative risk (RR) for women with diabetes versus women without diabetes was 1.43 [95% confidence interval (CI), 0.98-2.1]. The diabetes association was confined to women in the upper two BMI quintiles (RR, 1.47; 95% CI, 0.98-2.20), but a formal test of interaction was not statistically significant. Analyses that included diabetes ascertained at baseline and at follow-up gave similar results; the diabetes-associated RR in the higher BMI strata was 1.64 (95% CI, 1.16-2.31). We conclude that after adjustment for other risk factors, diabetes is associated with a modestly increased risk for endometrial cancer among women in this cohort.
Lifetime Prediction of Internally Pressurized Siliconized SiC Tubes Subjected to Creep Rupture Loading

The main objective of this research was to develop an experimental and analytical methodology to predict the lifetime of internally pressurized SiC tubes from the lifetimes of simple specimens subjected to similar delayed failure modes. Finite element analysis was used to determine the strain rate distribution in a thick-wall tube subjected to sustained internal pressure. This analysis was used along with the Monkman-Grant creep rupture criterion (obtained from creep testing of tensile specimens) to predict the lifetime of SCRB210 tubes. Results showed a large difference between experimental and predicted lifetimes. This difference was due to the existence of severe defects in the SCRB210 tubes which failed at low stresses. These tubes failed in crack growth mode rather than creep mode. This result leads to the conclusion that creep rupture criteria obtained from testing simple specimens cannot be projected to predict the lifetimes of large and more complex components.
Anti-Atheist Bias in the United States: Testing Two Critical Assumptions

Decades of opinion polling and empirical investigations have clearly demonstrated a pervasive anti-atheist prejudice in the United States. However, much of this scholarship relies on two critical and largely unaddressed assumptions: (a) that when people report negative attitudes toward atheists, they do so because they are reacting specifically to their lack of belief in God; and (b) that survey questions asking about attitudes toward atheists as a group yield reliable information about biases against individual atheist targets. To test these assumptions, an online survey asked a probability-based random sample of American adults (N = 618) to evaluate a fellow research participant (“Jordan”). Jordan garnered significantly more negative evaluations when identified as an atheist than when described as religious or when religiosity was not mentioned. This effect did not differ as a function of labeling (“atheist” versus “no belief in God”), or the amount of individuating information provided about Jordan. These data suggest that both assumptions are tenable: nonbelief—rather than extraneous connotations of the word “atheist”—seems to underlie the effect, and participants exhibited a marked bias even when confronted with an otherwise attractive individual.
Defending Rorty: Pragmatism and Liberal Virtue

Introduction: defending California: Richard Rorty's virtue liberalism 1. Rorty's pragmatism: the critique of philosophy 2. Rorty's pragmatic virtue liberalism 3. Critics: from left to right 4. Rorty vs Taylor: ontology, pluralism, and authoritarianism 5. Rorty, religion, and pragmatic liberalism 6. Rorty's liberal utopia and Huxley's pragmatist Island 7. Conclusion.
Shape modeling and matching in identifying 3D protein structures

In this paper, we describe a novel geometric approach in the process of recovering 3D protein structures from scalar volumes. The input to our method is a sequence of @a-helices that make up a protein, and a low-resolution protein density volume where possible locations of @a-helices have been detected. Our task is to identify the correspondence between the two sets of helices, which will shed light on how the protein folds in space. The central theme of our approach is to cast the correspondence problem as that of shape matching between the 3D volume and the 1D sequence. We model both shapes as attributed relational graphs, and formulate a constrained inexact graph matching problem. To compute the matching, we developed an optimal algorithm based on the A*-search with several choices of heuristic functions. As demonstrated in a suite of synthetic and authentic inputs, the shape-modeling approach is capable of identifying helix correspondences in noise-abundant volumes at high accuracy with minimal or no user intervention.
Climate Change: Politics and Practice

This autumn, President George W. Bush belatedly held international meetings to discuss global climate change. It may have been a calculated gesture from a leader whose political stock has been plummeting for some time. But the move underscored the dramatic shift in the debate over global warming. Mostly ignored for years, climate change had burst into view again between 2005 and 2007 for a number of reasons: the release of a major scientific report that the Arctic was melting; the unprecedented natural devastation on US soil of Hurricane Katrina; two more years of record heat in 2005 and 2006 followed by an ongoing severe drought in 2007; the release in early 2007 of a gloomy Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment of climate change; a renewed environmental and climate change movement symbolized by the popularity of Al Gore's An Inconvenient Truth ; and, of course, the sweep of the Republican Congress that had featured climate change deniers like Senator James (“it's a hoax”) Inhofe (R-OK).
The Ritual Meaning of Corn Pollen Among the Navajo Indians

Navajo religious rituals are so multifaceted that one has trouble perceiving any centre of gravity. The inevitable question is: What are the sources of unity behind the diversity of the chant system? Let us see what evidence there is among the Navajo that all religions tend to seek some point of contact with the divine.
High-quality ISA synthesis for low-power cache designs in embedded microprocessors

Energy efficiency, performance, area, and cost are critical concerns in designing microprocessors for embedded systems, such as portable handheld computing and personal telecommunication devices. This work introduces framework-based instruction set architecture (ISA) synthesis, which reduces code size and energy consumption by tailoring the instruction set to the requirement of a targeted application. This is achieved by replacing the fixed instruction and register decoding of general-purpose embedded processors with programmable decoders that can achieve application-specific processor performance, low energy consumption, and smaller code size while maintaining the fabrication advantages of a mass-produced single-chip solution. Experimental results show that our synthesized instruction set results in significant power reduction in the L1 instruction cache compared with ARM® instructions.
An assessment of variables affecting transition readiness in pediatric rheumatology patients

We sought to identify which adolescent patient characteristics might lead to subjective reported independence in accessing medical care when patients transition from pediatric to adult medicine. Pediatric and adult rheumatologists were asked which pediatric patient characteristics they believed would improve transition to adult medical care. Based on these responses, a questionnaire was created and administered to 76 teenage/young adult patients in a pediatric rheumatology clinic. The first set of questions included demographic, disease features, and life skills questions. The second set of questions pertained to self-reported independence in managing medical care. Data was analyzed to see if there were any significant associations between an individual’s response to demographic, disease feature, or life skills questions and the independence outcome questions. In our study, older age correlated with self-reported independence in almost all questions asked regarding accessing medical care. Other patient characteristics that were associated with increased self-perceived autonomy included having a younger parent, having a family member with a similar disease, longer disease duration, having a comorbid non-rheumatic diagnosis, and having had a summer job. The patient characteristics that we found associated with self-reported independence in obtaining medical care should be considered when determining which patients might be more likely to make a successful transition.