cssi/SciSciGPT-SciSciNet huggingface dataset:
The effects of flooding attacks on time-critical communications in the smart grid

Many smart grid communications are delay sensitive and have very strict timing requirements for message deliveries. For example, trip protection messages must be delivered to the destination within 3 ms according to IEC 61850. Such time-critical communications are vulnerable to flooding attacks which attempt to increase message delivery delay through congesting the network channel and exhausting the computation resources of the communicating nodes. However, there is a lack of understanding on how much flooding attacks affect message delivery delays. In this paper, we conduct experimental studies to investigate how flooding attacks affect message delivery delays for time-critical communications in smart grid. Our experiments are based on both wireless networks in a lab and wired networks in a real, industry-standard electric power facility. Experimental results show that even low-rate flooding attacks can significantly increase the message delivery delays, especially when wireless networks are used.
COMPARISON OF FIVE MENTAL WORKLOAD ASSESSMENT PROCEDURES IN A MOVING-BASE DRIVING SIMULATOR

Five methods of measuring mental workload (secondary task performance, visual occlusion, cardiac arrhythmia, subjective opinion rating scales, and primary task performance) were compared for sensitivity to changes in operator loading. Each was used to differentiate among low, medium and high levels of workload defined in terms of the application point of crosswind gusts in a driving task. The driving task was produced using an automobile driving simulator with a six-degree of freedom computer generated display, a four-degree of freedom physical motions system, and a four-channel sound system. Gusts at the front of the vehicle represented high workload levels, and gusts toward the center of the vehicle represented progressively lower levels of workload. The results showed significant differences among workload levels for subjective opinion scales and primary performance measures of lateral deviation, yaw deviation, and steering reversals. A relative sensitivity estimate of these would be, from highest to lowest sensitivity, steering reversals and yaw deviation, rating scales, and lateral deviation. The techniques of occlusion, cardiac arrhythmia, and secondary task performance yielded no significant workload effect.
Adaptive and context-aware reconciliation of reactive and pro-active behavior in evolving systems

One distinct characteristics of the context-aware systems is their ability to react and adapt to the evolution of the environment, which is often a result of changes in the values of various (possibly correlated) attributes. Based on these changes, reactive systems typically take corrective actions, e.g., adjusting parameters in order to maintain the desired specifications of the system's state. Pro-active systems, on the other hand, may change the mode of interaction with the environment as well as the desired goals of the system. In this paper we describe our (ECA)2 paradigm for reactive behavior with proactive impact and we present our ongoing work and vision for a system that is capable of context-aware adaptation, while ensuring the maintenance of a set of desired behavioral policies. Our main focus is on developing a formalism that provides tools for expressing normal, as well as defeasible and/or exceptional specification. However, at the same time, we insist on a sound semantics and the capability of answering hypothetical "what-if" queries. Towards this end, we introduce the high-level language LEAR that can be used to describe the dynamics of the problem domain, specify triggers under the (ECA)2 paradigm, and reason about the consequences of the possible evolutions.
15 The Role of Chemical Engineering in Fuel Manufacture and Use of Fuels

Publisher Summary The manufacture and use of petroleum-based fuels has been a major factor in the growth and content of chemical engineering. Chemical engineers have pioneered advances in separations, catalytic processes such as fluid catalytic cracking, hydroprocessing, and many others. Many of the advances in chemical engineering science have been stimulated by the need for quantitative understanding of these processes. Fuel use and manufacture draw on most of the principles of chemical engineering and often add the challenge of extreme conditions of high temperature, sharp gradients, and short residence times. This chapter highlights certain relevant areas of fuel process and combustion chemistry, reduction of pollutant emission, and char reactivity. The area of study interfaces with two of the intellectual frontiers in chemistry, namely chemical kinetics and chemical theory. Advanced chemical research helps to discern the most likely pathways for energy movement within molecules and the energy distribution among reaction products. The chapter highlights three catefories of options for reducing combustion-generated pollutant emission: cleaning of the fuel, postcombustion cleaning of stack gases, and lowering the formation, and promoting the destruction of pollutants in the combustion process. Chemical engineering can make important contributions to all three of these areas, but the most challenging is that of the combustion process modification. The chapter emphasizes that the practical motivation for understanding the microscopic details of char reaction stems from certain questions. Such questions are answered empirically. A more fundamental approach is needed to resolve issues related to fuel manufacturing and use of fuels.
Importance-sampled pulse broadening statistics before and after PMD compensation

We have shown analytically and numerically that, when a variable-delay polarisation mode dispersion (PMD) compensator is used, the residual pulse broadening (or its minimum value) is proportional to second-order PMD, even in cases where the PMD correlation bandwidth exceeds the pulse bandwidth. Since second-order PMD is one of the main factors contributing to the pulse broadening after PMD compensation, numerical investigations of PMD compensators should take into account a wide range of second-order PMD values.
Smart Materials and Structures

This chapter introduces smart materials suitable for use in vibration related problems. The remaining chapters in this section integrate smart structures into the context of vibration analysis, vibration prevention and structural health monitoring (diagnostics).
The Bass Parasites of Oneida Lake, 80 Years Later

A survey of largemouth (Micropterus salmoides) and smallmouth bass (Micropterus dolomieu) parasite communities in Oneida Lake, New York, was conducted in the summer of 2012 and compared to an earlier survey conducted by Van Cleave and Mueller during the summers of 1929 to 1931. The component helminth communities between surveys were 31% similar in composition for largemouth and 28% similar for smallmouth bass. Between species, the component helminth communities were considerably more similar in the present survey (71%) than in the survey conducted by Van Cleave and Mueller (47%). Seven species reported by Van Cleave and Mueller were present in this survey and 21 species are new records for the bass of Oneida Lake. Van Cleave and Mueller did not report prevalence values for several taxa (Monogenea, Copepoda, Myxozoa, and a Trichodina sp.) that were important for separation of parasite infracommunities in species space for both bass species. These parasites represented 28% of all species found in the current survey and may be ecologically important. Several species of parasites exhibited differences in prevalence between surveys. Two species (Rhipidocotyle papillosa and Crepidostomum cornutum) were absent from this survey but were reported as common in the 1929-1931 survey and almost certainly represent extirpations that coincide with the loss of their native bivalve hosts from Oneida Lake. Other differences in the parasite communities may also be explained by the ecological disturbances in Oneida Lake over the past 81 yr. The changes in bass parasite communities between surveys emphasize the importance of recognizing the historical nature of parasite communities, especially in ecosystems with a history of large-scale changes. Most importantly our findings suggest that, similar to trends observed in free-living freshwater biotic communities, anthropogenic ecosystem disturbances may homogenize fish parasite communities.
High frequency properties of shielded power cable. 3. Loss from neutral wire-shield interaction

In this paper, we describe the phenomenon and the basis for an analytic approximation for this loss, which we then compare with the loss as computed using finite-element analysis. The mathematical solution for the loss is too complicated to be included here. As a result, the full mathematical treatment of the problem has been submitted for publication. The discussion here will be restricted to a qualitative description of the phenomenon and graphical quantification with comparison to finite-element computations and measured data
Identity Management Strategies Among Lesbians of African Ancestry

ABSTRACT The authors present the results from a study investigating identity management strategies among African-ancestral lesbians within their families of origin. The researchers collected qualitative data from 16 African-ancestral lesbians, which were analyzed using the CQR method. From these responses we examined themes relating to the coming-out experiences, familial support patterns, and the integration and management of lesbian identities within African-ancestral families. We found that participants typically reported positive feelings and attitudes about themselves and their lesbian identities. Although levels of distress experienced during the coming-out process were mixed, our participants consistently endorsed the importance of relationships with family members as a means of more effectively managing their lesbian identities.
Meaningful graphics workstation performance measurements

Abstract We present how graphics workstation performance is currently advertised by workstation manufactures. We suggest that the manufacturers' performance numbers are not the best indicators of how well the system will perform. Four levels of graphics system performance measurement have been defined by the NCGA Graphics Performance Characterization group[1]. These levels are low-level primitives (points, lines, and polygons per second), pictures, systems (input and action response times), and applications. We suggest that the best indicator of a graphics workstation's performance capabilities is that of an application running on the system. For applications level performance measurements, there are many potential applications from which to choose. We suggest that three-dimensional visual simulators are one of the better applications to study as that type of system has a realistic mix of processor and graphics computational requirements. We describe one such system, the Moving Platform Simulator (MPS), developed at the Naval Postgraduate School with the goal of fully listing its capabilities and utilized graphics techniques. We then present how that system performs on a currently available, high-performance graphics workstation.
Histologie Investigation Of Glycol Methacrylate Embedded Chick Embryonic Tissue

SUMMARY Specific light microscopic investigations (i.e. histochemical) of early embryonic material have always been beset by difficulties in processing and obtaining tissue sections of good quality. The advent of glycol methacrylate (GMA) as an embedding medium now provides a means to overcome these inherent problems with this tissue. Investigations were carried out to assess the histological results produced by different fixatives and times of fixation of GMA embedded 5-day chick embryonic tissue. Optimum cellular preservation of all tissues occurred following fixation in a mixture of acetic acid, 95% ethanol and neutral buffered formalin (AAF). With the procedures described in this study, a new method is available for more comprehensive examination of all types of early embryonic material.
The Failed Search for the Neutral in the Secular: Public Bioethics in the Face of the Culture Wars

Public bioethics focuses on deliberating about, recommending, or establishing social policies or practices concerning health care and biotechnology. A brace of premises underlies much of the work of public bioethics. First, there is the view that, if one approaches reality and human life as if both were without ultimate significance, one will find that one shares a common public bioethics. That is, if one abstains not only from any religious concerns, but even from philosophical reflections on the circumstance that life might have ultimate meaning, one will be able to articulate a common neutral moral perspective that all persons can share and that can be the basis of a common public bioethics. The second premise is that the controversies in bioethics arise from the presence of religious belief, especially Christian belief, which supports a set of moral commitments that generate controversies that make the framing of public policy difficult. The view is that there is significant disagreement among persons who hold religious positions, particularly Christians, and that in public bioethics we should strive to eliminate these controversies by relying on a neutral moral framework. This paper documents and challenges these premises. It demonstrates that Christian bioethics finds itself already embedded in the field of secular moral controversy before it adds the perspectives it brings.
Mechanical properties and dual drug delivery application of poly(lactic-co-glycolic acid) scaffolds fabricated with a poly(β-amino ester) porogen.

Abstract Polymeric scaffolds that are biocompatible and biodegradable are widely used for tissue engineering applications. Scaffolds can be further enhanced by enabling the release of one or more drugs to stimulate regeneration or for the treatment of a specific disease or condition. In this study, poly(lactic-co-glycolic acid) (PLGA) microspheres were mixed with poly(β-amino ester) (PBAE) particles to create novel hybrid scaffolds capable of dual release of drug and growth factor. Fast-degrading PBAE particles loaded with the drug ketoprofen acted as porogens that provided a rapid 12 h release. The PLGA microspheres were loaded with a growth factor, bone morphogenetic protein 2, and fused together around the porogens to create a slow-degrading matrix that provided sustained release lasting 70 days. Drug release was further tailored by varying the amount of porogen added to the scaffold. Bioactivity measurements demonstrated that the scaffold fabrication technique did not damage the drug or protein. The compressive modulus was affected by the amount of porogen added, extending from 50 to 111 MPa for loadings from 60 to 40% PBAE, and after 5 days of degradation, it decreased to 0.6 to 1.1 kPa when the porogen was gone. PLGA containing a quick-degrading porogen can be used to release two drugs while developing a porous microarchitecture for cell ingrowth with in a matrix capable of maintaining a compressive modulus applicable for soft tissue implants.
A Comparison of Neuropsychological Dysfunction in First-Episode Psychosis Patients with Unipolar Depression, Bipolar Disorder, and Schizophrenia

The severity and profile of cognitive dysfunction in first episode schizophrenia and psychotic affective disorders were compared before and after antipsychotic treatment. Parallel recruitment of consecutively admitted study-eligible first-episode psychotic patients (30 schizophrenia, 22 bipolar with psychosis, and 21 psychotic depression) reduced confounds of acute and chronic disease/medication effects as well as differential treatment and course. Patient groups completed a neuropsychological battery and were demographically similar to healthy controls (n=41) studied in parallel. Prior to treatment, schizophrenia patients displayed significant deficits in all cognitive domains. The two psychotic affective groups were also impaired overall, generally performing intermediate between the schizophrenia and healthy comparison groups. No profile differences in neuropsychological deficits were observed across patient groups. Following 6 weeks of treatment, no patient group improved more than practice effects seen in healthy individuals, and level of performance improvement was similar for affective psychosis and schizophrenia groups. Although less severe in psychotic affective disorders, similar profiles of generalized neuropsychological deficits were observed across patient groups. Recovery of cognitive function after clinical stabilization was similar in mood disorders and schizophrenia. To the extent that these findings are generalizable, neuropsychological deficits in psychotic affective disorders, like schizophrenia, may be trait-like deficits with persistent functional implications.
Inhibition of Monoamine Oxidase by the Pesticide Chlordimeform and Related Compounds

CHLORDIMEFORM is a formamidine acaricide and insecticide used to control phytophagous mites, cattle ticks and certain lepidopterous insects. Because of its unique spectrum of biological activity with regard to selectivity, chlordimeform may be the forerunner of a new class of agricultural chemicals. Although its mechanism of action is unknown, Knowles and Roulston1, studying the action of chlordimeform and related compounds on the southern cattle tick, suggested that inhibition of monoamine oxidase (MAO) could be involved. This hypothesis was based on observations of ticks poisoned with formamidine compounds and on the known ability of amidine compounds, such as propamidine and pentamidine, to inhibit MAO from mammals2. We have observed that symptoms manifested by rats poisoned by chlordimeform and demethylchlordimeform are similar to those elicited by sympathomimetic agents including known MAO inhibitors (unpublished results of F. R. Johannsen and C. O. K.). Thus, it seemed appropriate to examine chlordimeform and related compounds as potential inhibitors of rat liver MAO in vitro.
Converting Enzyme Inhibition in Chronic Renal Failure

Ten patients with chronic renal failure whose hypertension was controlled with triple drug therapy consisting of propranolol-hydralazine-furosemide were switched to the angiotensin-converting enzyme (ACE) inhibitor captopril for a period of 12 months. Control of hypertension was similar with both anti hypertensive regimens. Clearance of inulin and of paraaminohippuric acid increased during the first 3 months of captopril therapy and remained stable thereafter. Moreover, the decline in the reciprocal of serum creatinine over time observed during triple drug therapy was arrested during therapy with the ACE inhibitor. If the salutary effects of captopril are sustained, the results obtained in the current studies would suggest that control of hypertension by ACE inhibition may be effective in slowing progression of renal failure. Future studies to answer this important question are necessary.
CLASSROOM PERFORMANCE, HEALTH, SOCIAL FACTORS OF VERY LOW BIRTH WEIGHT (VLBW) CHILDREN: FOLLOW-UP AT 5–8 YEARS

Increasing survival of VLBW infants causes concern for long term health and educational needs. This study was designed to locate VLBW children at school age, to compare educational services they required with peers and term siblings and to review computerized data of the hospital course. Parental, educational and medical information was obtained from questionnaires, interviews and clinic or field visits. Of 43 neonates weighing ≤1250g (±SEM =1076g±19.2) admitted for intensive care from 1974-1978 and surviving to school age, 7 were lost to follow-up and 3 have yet to attend school. Of the 33 VLBW children in school, 3(9.1%) were in classes for the major handicapped while 30(90.9%) were found comparable to their classmates by teachers or test scores; however, 14/30 (47%) required remedial instruction to perform at grade level. Major medical problems included seizures, spastic diplegia and visual or hearing loss. Of 13 VLBW children with siblings in school, 3 required more specialized staff than their siblings. The group without the need for specialized teaching staff had older maternal ages (±SEM=24.7yrs±1.28 vs 21.7±0.74,p<0.05, t-test) and tended to reside in higher socioeconomic households by Hollingshead Index (p<0.10,X2) which may have resulted in more stimulation at home. The VLBW children had a greater proportion (17/33, 51.5%) requiring specialized instruction than the general school population (24%, p<0.001,X2), although with this instruction most compared favorably with classmates.
Comparison of Arsenic and Phosphate Uptake and Distribution in Arsenic Hyperaccumulating and Nonhyperaccumulating Fern

Abstract Uptake of arsenic (As) and its distribution in Chinese Brake fern (Pteris vittata L.), an As hyperaccumulator, and Boston fern (Nephrolepis exaltata L.), a nonhyperaccumulator, in the presence of phosphorus (P), were characterized by employing a hydroponic experiment with a complete three-factorial design. Two levels of As (100 and 1000 µM) and four levels of P (0, 100, 500, and 1000 µM) were used in this study. Arsenic uptake rates on the basis of root fresh weight for the two ferns were similar at low As concentration (100 µM). At high As concentration (1000 µM), however, As uptake rates (373–987 nmol g−1 f wt h−1) of P. vittata were significantly greater than those of N. exaltata (164–459 nmol g−1 f wt h−1). In both ferns, addition of P reduced their As uptake rate as well as accumulation. Pteris vittata had a greater As TF (Translocation factor = concentration ratio of fronds to roots) than N. exaltata. On the contrary, N. exaltata displayed a greater P TF than P. vittata. As a result, high P...
The DeSyGNER knowledge management architecture: a building block approach based on an extensible kernel

The Decision Systems Group has been developing a 'building block' approach for creating Knowledge Management (KM) applications for medical education and decision support. Potential functions and knowledge access modes to be supported include query, browsing, testing, simulation, didactic instruction, problem solving, and personal file management. Knowledge is considered to be available in multiple forms, non-adaptive and adaptive. We believe that organization and combination of disparate components, in order to build varied and complex applications as required for KM, is best achieved through a software engineering approach based on a kernel set of functions that provide a consistent set of services for all applications, facilitating extensibility and inter-application compatibility. For this purpose, we are exploring a prototype kernel architecture called DeSyGNER (the Decision Systems Group Nucleus of Extensible Resources). Features addressed by DeSyGNER include methods for decomposition of applications into modular units and identification of their functional dependencies; methods of structuring applications to separate their storage, processing, and presentation components; database requirements for indexing and composing complex structures from disparate, disjoint data elements; and methods to support multi-user cooperative development.
Using a multi-parameter approach to reassess maturity of spiny dogfish, squalus acanthias, following increased fishing pressure in the western north atlantic

Abstract Age at size was linked to sexual maturity in 147 male and 249 female spiny dogfish, Squalus acanthias, from the Gulf of Maine using three criteria: (1) gross reproductive morphology, (2) histology and (3) steroid hormone concentrations. Collected specimens ranged from 25 cm to 102 cm stretch total length, and 0 to 24 years old. Maturity ogives for males, based on data gathered for clasper length, circulating testosterone concentrations and proportion of tissue with mature spermatocysts within the testes, predicted that 50% maturity occurred at a total length of 63.1 mm and 7.5 years of age. For females, maturity ogives, based on data gathered for embryo presence, ovary mass, shell gland mass, follicle size and circulating estradiol concentrations, predicted that 50% maturity occurred at a total length of 76.9 cm and 9.1 years of age. These maturity parameters for females decreased by over 7 cm and 3 years from those previously reported two decades ago for S. acanthias in the Western North Atlantic. While the causes for the decrease in maturity parameters could not be determined, as this was beyond the scope of the current study, these changes occurred over a period of increased fishing pressure.
A new open ocean, hybrid coordinate primitive equation model

Abstract A new open ocean hybrid coordinate primitive equation model based on the standard model of Bryan and Cox has been developed for regional applications. Several issues of regional modeling are addressed, including: model initialization; open boundary conditions; and horizontal filtering on sloping coordinate surfaces. The applicability of the new regional model for applications to mesoscale ocean modeling is demonstrated. The open boundary conditions are calibrated against a primitive equation reference ocean for three realistic flow regimes. The analytic solution for f -plane flow over a gaussian bump with constant stratification is reproduced. A comparison is made between the regional primitive equation model and the Harvard Open Ocean Quasigeostrophic model for a simulated mesoscale eddy field for a 30 day simulation. Differences in the two model calculations are attributed to model physics and not numerics or representations of the model variables.
Removal of dissolved aluminum (released by acid rain) using decaying leaves I. Effects of ph and species of leaves

Aluminum ion appears to be toxic to fish particularly at low pH levels. It is important, therefore, to try to remove aluminum ion from water. The short and long term effects of leaves on reducing aluminum concentration in water have been examined. The overall effect of pH on this process has also been studied. Five common species of leaves have been used and their capacities for removing aluminum from solution have been studied. Results showed that leaves absorbed aluminum in widely varying degrees, depending on the type of leaf and the pH of the solution.
Object aggregation using Neyman-Pearson analysis

This paper presents a novel approach to: 1) distinguish military vehicle groups, and 2) identify names of military vehicle convoys in the level-2 fusion process. The data is generated from a generic Ground Moving Target Indication (GMTI) simulator that utilizes Matlab and Microsoft Access . This data is processed to identify the convoys and number of vehicles in the convoy, using the minimum timed distance variance (MTDV) measurement. Once the vehicle groups are formed, convoy association is done using hypothesis techniques based upon Neyman Pearson (NP) criterion. One characteristic of NP is the low error probability when a-priori information is unknown. The NP approach was demonstrated with this advantage over a Bayesian technique.
Prognostic value of E/E' ratio in patients with unoperated severe aortic stenosis.

Objectives The aim of this study was to evaluate the value of clinical and echo-Doppler parameters for the prognosis of unoperated severe aortic stenosis (AS). Background Approximately one-third of severe, symptomatic AS patients are denied surgery. Risk stratification of unoperated AS is important to determine eligibility for percutaneous aortic valve replacement, an evolving treatment option for AS patients deemed suboptimal for surgical aortic valve replacement. Methods We retrospectively compared clinical and echo-Doppler parameters between survivors and nonsurvivors of 125 patients with unoperated severe AS. Results The 1-year survival rate was 62.4%. In univariate analysis, survivors compared with nonsurvivors were younger (80.0 ± 10.9 years vs. 84.9 ± 11.1 years, p = 0.02), had a greater left ventricular ejection fraction (LVEF) (55 ± 15% vs. 50 ± 16%, p = 0.042), a higher left ventricular stroke volume (63 ± 19 ml vs. 56 ± 13 ml, p = 0.015), a lower E/E′ ratio (12.19 ± 5.7 vs. 16.87 ± 7.43, p 15 (20% vs. 55%, p 15 had a 73.8% and 47.8% 1-year survival rate, respectively (p = 0.027). In the patients with an LVEF 15 demonstrated a 70.6% and 22.3% 1-year survival rate, respectively (p = 0.003). In multivariate analysis, significant predictors of mortality were E/E′ >15 and a combination of E/E′ >15 and B-type natriuretic peptide >300 ng/ml: adjusted mortality risk 2.34 (95% confidence interval (CI) 1.27 to 4.33, p = 0.0072) and 2.59 (95% CI 1.21 to 5.55, p = 0.014), respectively. Conclusions The E/E′ ratio is the single most predictive clinical and echo-Doppler parameter in the assessment of overall prognosis in patients with unoperated severe AS. LVEF was a significant predictor of survival only in the univariate analysis. B-type natriuretic peptide alone was not a predictor of prognosis in the study population. However, the combination of E/E′ and B-type natriuretic peptide is even more predictive of the 1-year prognosis.
Mixtures of Bose liquids at finite temperature

The superfluidity of two weakly interacting Bose gases at finite temperature is studied with the Bogoliubov model. At low temperatures, only the lowest energy normal modes are relevant, exciting particles of each species from their respective condensates. The low-temperature depletion of the zero-momentum condensate and superfluid density are calculated for arbitrary mixtures. For identical short-range interaction between all particles and low concentrations of one species, curves of constant depletion and superfluid density have a form similar to those of a free Bose gas. These considerations suggest that superfluid flow of the unstable isotope /sup 6/He at low concentrations (< or approx. =10/sup -9/) in liquid /sup 4/He would be detectable only at temperatures below approx.10/sup -6/ K. Other, more general interaction potentials predict similar behavior.
SPECTROSCOPIC FACTORS FROM DEUTERON STRIPPING REACTIONS LEADING TO GROUND AND FIRST EXCITED STATES OF EVEN SPHERICAL NUCLEI.

Deuteron stripping reactions on odd-neutron targets from Cr to Sm leading to the ground and first excited states of the even system are analyzed with distorted-wave Born approximation calculations. Theoretical spectroscopic factors are computed for these reactions using wave functions derived from the pairing-plus-${P}^{(2)}$ model. One such factor is calculated and measured for the ground-state transition, while for the first excited state the analysis is in terms of several spectroscopic factors corresponding to several $l$ values for the transferred neutron. For the ground state, the agreement between experiment and theory is excellent. For the excited state the agreement is not so good, but most of the spectroscopic factors are in agreement to about a factor of 2.
Identification of the Escherichia Coli SecA Solution State Dimer Orientation using Forster Resonance Energy Transfer

Over the past 8 years four different SecA dimer crystal structures have been solved. While the subunits of the dimer remain essentially the same, the orientation of the subunits is drastically different for each of the crystal structures. Some data has been published (Ding, H., Hunt, J.F., Mukerji, I., Oliver, D.B. 2003 Biochemistry 42, 8729-38) that suggest one of the anti-parallel dimers (Hunt, J.F., Weinkauf, S., Henry, L., Fak, J.J., McNicholas, P., Oliver, D.B., Deisenhofer, J. 2002 Science 297, 2018-26) is the solution state orientation, while other data suggests that it is the parallel dimer (Vassylyev, D.G., Mori, H., Vassylyeva, M.N., Tsukazaki, T., Kimura, Y., Tahirov, T.H., Ito, K. 2006 J Mol Biol 364, 248-58). Thus, the solution state orientation of the SecA dimer is currently unknown. The aim of the present study is to identify the dominant dimer orientation of E. coli SecA in solution. Forster Resonance Energy Transfer (FRET) was used to measure distances between dye-labeled monocysteine residues on SecA dimer subunits. Three fluorescent dye pairs with R0 values of 34 A, 62 A, and 82 A were used to measure distances from ∼11 A to 140 A, which corresponds to the possible distances expected within any of the 4 proposed dimer orientations. The FRET measured distances were then compared to those measured in the SecA dimer crystal structures to determine if one of the structures represents the dominant solution state dimer orientation or if a mixed population of dimer states appears likely.Funding provided by National Institute of Health
Period Doubling and Chaotic Behavior in a Driven Anharmonic Oscillator

A driven anharmonic oscillator is described which exhibits period doubling and chaotic behavior. The measured behavior of the oscillator under successive period doublings is in quantitative agreement with a recent theory which describes the behavior of nonlinear systems. Both the scalirg and the convergence rate predicted by the theory are verified by the experiment. The oscillator also exhibits period tripling and quintupling.
Microgap X-ray nanolithography

Abstract At linewidths of 0.1μm and below, the time required to expose large-area patterns (∼1cm 2 ) by electron-beam lithography becomes impractically long. Thus, there is a critical need for reliable replication techniques in this linewidth domain. Replication of features as fine as 18nm by x-ray lithography has been demonstrated. However, all sub-0.2μm-linewidth x-ray lithography to date has been done in intimate contact using polyimide-membrane masks. Polyimide is subject to distortion, and contact can cause mask damage. For these reasons we have investigated x-ray nanolithography with inorganic membranes, and mask-sample gaps of ∼4μm. We discuss the resolution-limiting factors of penumbra, diffraction, and photo-electron range, and consider the tradeoffs of gap and wavelength that need to be made to achieve high resolution. With a Cu L source (λ=1.3nm), a linewidth of 0.1μm requires a gap of ∼4μm. We have used stress-controlled SiON 0.5 membranes of 6cm 2 area attached to a narrow rim etched into a Si substrate. The gap was set by small spaces studs. Gaps of 4–6μm were achieved with uniformities of ∼0.5μm. They were measured using an angular fringe counting technique. Microgap nanolithography was used to replicate 100nm lines with the Cu L x-ray. High aspect-ratio PMMA structures were achieved with steep sidewalls, suggesting that 50nm lines could be faithfully printed with the microgap technique.
Block Bootstrap Estimation of the Distribution of Cumulative Outdoor Degradation

An interesting prediction problem involving degradation of materials exposed to outdoor environments (weathering) is estimating the distribution of future cumulative degradation using small- to moderate-sized degradation datasets. This distribution, which is assumed to arise as a result of the uncertainty/variability in the weather, can be expressed mathematically as the distribution of the sum of a periodic dependent time series and is approximately normal by the central limit theorem. The estimation of this distribution is thus equivalent to estimating the mean and the variance of the distribution. In this article, we propose a block bootstrap-based approach for the estimation and a novel technique to estimate the variance of the distribution. We provide an example involving the degradation of a solar reflector material, as well as the results of a simulation study to show the efficacy of the proposed estimators. We also give a procedure for constructing an approximate confidence interval for the probab...
A method for preparing and maintaining rhesus monkeys with chronic venous catheters

A procedure for implanting and maintaining chronic venous catheters in primates is described. Surgical procedures and hardware suitable for maintaining the S in operant behavior equipped cages are presented. All equipment can be assembled with hand tools or obtained from commercial sources at low cost.
Rauwolfia and guanethidine: Pharmacology and clinical use in treatment of hypertension

Abstract Both reserpine and guanethidine appear to utilize the same fundamental pharmacological mode of action which leads to depletion of tissue catecholamines. Guanethidine produces effects on the blood pressure similar to those of the ganglion-blocking agents without the troublesome side effects. It is an extremely potent agent, however, and is likely to produce symptoms attributable to postural hypotension.
The non-commutative Gurarii space

We construct a “universal space” for 1-exact finite dimensional operator spaces (an analogue of the Gurarii space).
Influence of Cu diffusion conditions on the switching of Cu-SiO2-based resistive memory devices

Abstract This paper presents a study of Cu diffusion at various temperatures in thin SiO 2 films and the influence of diffusion conditions on the switching of Programmable Metallization Cell (PMC) devices formed from such Cu-doped films. Film composition and diffusion products were analyzed using secondary ion mass spectroscopy, Rutherford backscattering spectrometry, X-ray diffraction and Raman spectroscopy methods. We found a strong dependence of the diffused Cu concentration, which varied between 0.8 at.% and 10 − 3 at.%, on the annealing temperature. X-ray diffraction and Raman studies revealed that Cu does not react with the SiO 2 network and remains in elemental form after diffusion for the annealing conditions used. PMC resistive memory cells were fabricated with such Cu-diffused SiO 2 films and device performance, including the stability of the switching voltage, is discussed in the context of the material characteristics.
Structure of the liquid-vapor interface of a dilute ternary alloy: Pb and In in Ga

We report the results of grazing incidence x-ray diffraction and x-ray reflectivity studies of the liquid-vapor interfaces of three dilute ternary alloys, composed of a small constant amount of Pb (0.072 at. %) and a small variable amount of Sn (0.12, 3.4, and 7.7 at. %) dissolved in Ga. The solutes Pb and Sn compete to segregate in the liquid-vapor interfaces of these alloys; in each case, over the temperature range studied (30--120 \ifmmode^\circ\else\textdegree\fi{}C), the composition of the outermost layer of the interface is dominated by excess Pb. In the case of the alloy with Sn concentration of 0.12 at. %, the excess Pb in the liquid-vapor interface forms a crystalline monolayer that melts at 67.8 \ifmmode^\circ\else\textdegree\fi{}C. In the case of the alloy with Sn concentration of 3.4 at. %, the excess Pb in the liquid-vapor interface again forms a crystalline monolayer, but that crystalline monolayer melts at 40.5 \ifmmode^\circ\else\textdegree\fi{}C. In the case of the alloy with Sn concentration of 7.7 at. %, the excess Pb in the liquid-vapor interface forms a two-dimensional liquid over the entire accessible temperature range. When the excess Pb in the liquid-vapor interface forms a two-dimensional crystal, it fully covers the surface of the liquid; at higher temperatures, when the Pb monolayer is liquid, it only partially covers the liquid alloy surface, with the remainder covered by a partial monolayer of liquid Sn. Two-dimensional liquid Pb and two-dimensional liquid Sn appear to be immiscible under the conditions of our experiments. In the case of the sample with the smallest concentration of Sn, the correlation length obtained from the width of the diffraction peak drops almost discontinuously at 67.8 \ifmmode^\circ\else\textdegree\fi{}C to a smaller value. It then further decreases continuously until about 90 \ifmmode^\circ\else\textdegree\fi{}C, thereafter becoming constant. These data suggest the existence of an intermediate disordered phase stable between 67.8 and 90 \ifmmode^\circ\else\textdegree\fi{}C. Our experiments fall short of providing unambiguous evidence for the existence and character of this disordered phase. We speculate that between 67.8 and about 90 \ifmmode^\circ\else\textdegree\fi{}C the Pb monolayer has a hexatic structure and that above 90 \ifmmode^\circ\else\textdegree\fi{}C it is liquid, as is implied by the results of recent simulations of the temperature dependence of the structure of a quasi-two-dimensional layer of Pb.
Characterizing Solar PV Output Variability and Effects on the Electric System in Florida, Initial Results

This paper shares initial results from a major collaborative project in Florida underway to study and address effects of high penetration levels of solar photovoltaic (PV) generation on the electric power system. The effort includes characterizing the variability of the solar resource in Florida, where a number of new multi-megawatt solar projects have either recently come online or are in the planning or construction stages (including the largest solar PV generating station in N. America at the time of this writing). Until now, most work on characterizing solar variability has focused on the Southwestern U.S. This paper shares initial results and insights on the variability of Solar PV generation output in Florida on different timescales and provides some preliminary insights into the implications and effects of the variability on the successful integration of increasingly higher penetration levels of solar PV, with respect to the integration technology, control systems, and the electric power system.Copyright © 2011 by ASME
Improving compliance and increasing control of hypertension: Needs of special hypertensive populations

Approximately 60 million people in the United States have hypertension. More than half are either untreated or treated without blood pressure control, despite the well-known risks of hypertension and the established benefits of treatment. The major reason for inadequate control of hypertension is poor adherence to treatment. Approximately 50% of patients with hypertension fail to keep follow-up appointments, and only 60% take their medications as prescribed. Barriers to effective therapeutic adherence include poor doctor-patient communication, cost of antihypertensive therapy, and side effects of the drugs. To increase control of hypertension, compliance with therapy must be improved. Physicians and patients must be mutually committed to achieving control of blood pressure. Physicians should communicate instructions clearly and prescribe therapies that are effective, affordable, and have minimal or no adverse effects on patient quality of life or overall cardiac risk profile. The needs of special hypertensive populations (i.e., elderly, black, and young patients) must also be recognized and addressed. Patients must follow recommendations and alert their physicians to any problems with their medications--particularly those relating to side effects and cost. When selecting drug therapy it should be noted that older patients are sensitive to volume depletion and sympathetic inhibition. In this group of patients, initial drug doses should be low and increments smaller and more gradual than in younger patients. Black patients with hypertension show an accentuated response to diuretics and blunted responses to beta-blockers and angiotensin-converting enzyme (ACE) inhibitors as monotherapy. However, when used with a diuretic, there are no racial differences in the blood pressure lowering effects of beta-blockers and ACE inhibitors.(ABSTRACT TRUNCATED AT 250 WORDS)
The accumulation and metabolism of [14C]hypoxanthine by slices of rabbit renal medulla

The uptake of hypoxanthine by rabbit renal medulla has been studied with in vitro conditions. Unlike the uptake by renal cortex slices reported earlier, no evidence was found for involvement of an organic cation transport system. Medullary accumulation of the 14C-labeled material occurred in the absence of O2 if glucose was present as substrate. Uptake of the 14C label was not supported by other sugars or metabolic intermediates, however. Metabolic inhibitors reduced both aerobic and anaerobic uptake. Tissue extracts were subjected to high-voltage electrophoresis and gel filtration for identification of possible metabolites. These studies indicated that most of the uptake of 14C-labeled material was accounted for by its conversion to inosine-like and/or inosinic acid-like compounds. That is, when experimental conditions were designed to retard slice metabolism of hypoxanthine, tissue to medium ratios for 14C approximated 1.0. A third metabolite was found occasionally, but remains unidentified.
The Petrology and Geochemistry of the Azores Islands

Forty lavas from the Azores Islands have been analyzed for 87Sr/86Sr ratios, major elements, first transition series metals, and LIL elements. The samples belong to the alkali basalt magma series but range from transitional hy-normative basalts from Terceira to basanitoids from Santa Maria. Differentiated lavas include both typical trachytes and comenditic trachytes and comendites. Major and trace element concentrations define smooth trends on variation diagrams, and these trends can be related to phases crystallizing in the rocks. Systematic interisland differences are also apparent in these variation diagrams. LIL element concentrations in island basalts are roughly twice as high as those in tholeiites from the adjacent Mid-Atlantic Ridge which transects the Azores Plateau. 87Sr/86Sr ratios in lavas from 6 of the 9 islands range from 0.70332 to 0.70354, a range similar to that found in tholeiites from the Mid-Atlantic Ridge transect of the Azores Plateau. This suggests that lavas from these islands and this portion of the Mid-Atlantic Ridge may be derived from a similar source. However, lavas from the islands of Faial and Pico have 87Sr/86Sr ratios up to 0.70394 and ratios in Sao Miguel lavas range up to 0.70525, suggesting basalts from these islands are derived from a chemically distinct source. Differences in the average LIL element concentrations of the least fractionated ridge tholeiites from the Azores Plateau and alkali basalts from the islands result from differences in extent of partial melting and residual mineralogy. The alkali basalts are derived by roughly half as much melting as are the tholeiites. Trace element concentrations in Azores peralkaline lavas preclude their derivation by partial melting of peridotitic mantle or basaltic crust; rather the data suggest they are produced by fractional crystallization of a basaltic parent.
Determination of the partition coefficient for yeast invertase between microwater droplets in air in contact with liquid water

The experiments carried out in the separatory funnel provide a simple technique for concentrating proteins up to 30 times. From a feed concentration of 0.1 g Lr, it is possible to obtain a condensed droplet solution with a concentration as high as 3 g L-1. The directly determined equilibrium constant (from the separatory funnel experiments) matched well with that estimated from the air-fluidized bed data (using an equilibrium model corrected with an efficiency term).
A phase 1 trial dose-escalation study of tipifarnib on a week-on, week-off schedule in relapsed, refractory or high-risk myeloid leukemia

Inhibition of farnesyltransferase (FT) activity has been associated with in vitro and in vivo anti-leukemia activity. We report the results of a phase 1 dose-escalation study of tipifarnib, an oral FT inhibitor, in patients with relapsed, refractory or newly diagnosed (if over age 70) acute myelogenous leukemia (AML), on a week-on, week-off schedule. Forty-four patients were enrolled, two patients were newly diagnosed, and the rest were relapsed or refractory to previous treatment, with a median age of 61 (range 33-79). The maximum tolerated dose was determined to be 1200 mg given orally twice daily (b.i.d.) on this schedule. Cycle 1 dose-limiting toxicities were hepatic and renal. There were three complete remissions seen, two at the 1200 mg b.i.d. dose and one at the 1000 mg b.i.d. dose, with minor responses seen at the 1400 mg b.i.d. dose level. Pharmacokinetic studies performed at doses of 1400 mg b.i.d. showed linear behavior with minimal accumulation between days 1-5. Tipifarnib administered on a week-on, week-off schedule shows activity at higher doses, and represents an option for future clinical trials in AML.