cssi/SciSciGPT-SciSciNet huggingface dataset:
Factor analysis for quantitation of myocardial blood flow (MBF) using /sup 13/N-ammonia dynamic PET imaging

Regional myocardial blood flow (MBF) can be measured by /sup 13/N-ammonia PET dynamic imaging using the conventional modeling approach that requires blood sampling, region-of-interest (ROI) drawing and a time-consuming nonlinear regression on each time activity curve (TAC). In this study, the factor analysis of dynamic structures (FADS) was used to extract the "pure" blood pool TAC and generate a parametric image of MBF (pixel unit: ml/min/g) which can map the myocardial perfusion accurately, Ten dynamic /sup 13/N-ammonia dog PET studies (3 baseline, 5 hyperemia, and 2 occlusion) were included. Three factors (TACs) and their corresponding factor images (the tight and left ventricular (RV and LV) blood pools and myocardial activities) were extracted from each study. The LV factors matched well with the plasma TACs, The factor image of myocardium was then converted to parametric image of MBF using a relationship derived from a two-compartment model, The results showed that the MBF obtained from PADS correlated well with MBF by two-compartment model fitting (correlation coefficient (r)t 0.98, slope=0.83) and by microsphere technique (r=0.98, slope=0.95). The FADS generated MIBF images have good image quality and lower noise levels compared to those generated by Patlak graphical analysis (PGA). It is concluded that regional myocardial blood flow can be measured accurately and noninvasively from /sup 13/N-ammonia dynamic PET imaging and FADS technique. FADS provides a simple method to map the distribution and magnitude of myocardial perfusion accurately and generate parametric image of MBF without requiring blood sampling and spillover correction. >
Producing next-generation biofuels from filamentous cyanobacteria: An economic feasibility analysis

Abstract The need for renewable, sustainable sources of biofuels continues to increase as the world’s population continues to grow. Using microorganisms as biofuel producers is one area that is being researched extensively for this purpose. Anabaena sp. PCC 7120 is a filamentous strain of cyanobacteria capable of fixing atmospheric nitrogen, and has been genetically engineered to produce limonene, a cyclic hydrocarbon which has potential as a next-generation biofuel. This study analyzed the economic feasibility of a theoretical next-generation production facility that uses genetically engineered Anabaena 7120 to produce limonene. The economic feasibility of a limonene production facility was analyzed using the Farm-level Algae Risk Model (FARM). This model is an integrated systems compilation of numerous technoeconomic models that has been used previously in several algal production scenarios. FARM simulated 10 years of operation for the production facility for two scenarios. The 1st scenario used actual limonene productivity data (0.018 mg/L/d) from a genetically engineered strain of filamentous cyanobacteria, while the 2nd scenario used a ‘best case’ assumption that limonene productivity can be increased 100-fold (1.8 mg/L/d). It was determined that the average probability of economic success of the 1st scenario at year 5 was 0%, while the average probability of success of the 2nd scenario was 100%. Assuming no fractional reductions in OPEX and CAPEX, the average net present value (NPV) at year 5 of the 1st scenario was −$588 million, compared to $392 million for the 2nd scenario. Further analysis determined that a limonene productivity of 1.02 mg/L/d is needed to yield an NPV of 0 dollars at year 5. This study shows strong evidence that a next-generation biofuel production facility utilizing genetically engineered strains of filamentous cyanobacteria could become economically feasible in the future if strains are developed with increased biofuel productivities.
Fecal Microbiota Transplantation: Harnessing the Gut Microbiota to Treat Disease: Despite technical and regulatory questions, this procedure appears effective for treating patients with persistent Clostridium difficile infections

Fecal microbiota transplantation (FMT) involves the transfer of consortia of bacteria from healthy individuals to patients with Clostridium difficile infection (CDI) or other conditions to promote recolonization with missing components of intestinal flora. FMT dates as far back as 4th-century China when human fecal suspensions were used to treat food poisoning and severe diarrhea and has been used in veterinary medicine to treat ruminal disorders at least as far back as the 17th century.
Cruise Speed Sensitivity Study for Transonic Truss Braced Wing

NASA's investment and research in aviation has led to new technologies and concepts that make aircraft more efficient and environmentally friendly. One aircraft design operational concept is the reduction of cruise speed to reduce fuel burned during a mission. Although this is not a new idea, it was used by all of the contractors involved in a 2008 NASA sponsored study that solicited concept and technology ideas to reduce environmental impacts for future subsonic passenger transports. NASA is currently improving and building new analysis capabilities to analyze advanced concepts. To test some of these new capabilities, a transonic truss braced wing configuration was used as a test case. This paper examines the effects due to changes in the design cruise speed and other tradeoffs in the design space. The analysis was baselined to the Boeing SUGAR High truss braced wing concept. An optimization was run at five different design cruise Mach numbers. These designs are compared to provide an initial assessment space and the parameters that should be considered when selecting a design cruise speed. A discussion of the design drivers is also included. The results show that the wing weight in the current analysis has more influence on the takeoff gross weight than expected. This effect caused lower than expected wing sweep angle values for higher cruise speed designs.
Pharmacokinetics of sternal intraossesous atropine administration in normovolemic and hypovolemic swine.

Objective: Characterize and compare the pharmacokinetics of atropine administered via the sternal intraosseous (IO) route in a normovolemic and hypovolemic swine model. Design: Prospective, experimental study. Setting: Vivarium. Subjects: Yorkshire-cross swine (N = 12). Intervention: Atropine was administered via the sternal IO route to normovolemic and hypovolemic swine. Blood samples were drawn at regular intervals after atropine administration and analyzed for plasma atropine concentration. Pharmacokinetic parameters were obtained from modeling the plasma concentrations. Main Outcome Measurements: Pharmacokinetic parameters, maximum concentration (Cmax), and time to maximum concentration (Tmax). Results: The normovolemic and hypovolemic models reached peak plasma concentration immediately and had a very rapid distribution phase with no apparent absorption phase for the IO groups. The hypovolemic group had slower clearance and longer half-life compared to the normovolemic group. Conclusion: The sternal IO route is an effective method of administering atropine and is comparable to the previously reported tibial IO and intravenous data even under conditions of significant hemorrhage.
Retinoic acid receptor gamma impacts cellular adhesion, Alpha5Beta1 integrin expression and proliferation in K562 cells

The interplay between cellular adhesion and proliferation is complex; however, integrins, particularly the α5β1 subset, play a pivotal role in orchestrating critical cellular signals that culminate in cellular adhesion and growth. Retinoids modify the expression of a variety of adhesive/proliferative signaling proteins including α5β1 integrins; however, the role of specific retinoic acid receptors involved in these processes has not been elucidated. In this study, the effect of all-trans-retinoic acid receptor (RAR) agonists on K562 cellular adhesion, proliferation, and α5β1 integrin cell surface expression was investigated. RARγ agonist exposure increased K562 cellular adhesion to RGD containing extracellular matrix proteins fibronectin and FN-120 in a time- and concentration dependent manner, while RARα or RARβ agonist treatment had no effect on cellular adhesion. Due to the novel RARγ- dependent cellular adhesion response exhibited by K562 cells, we examined α5 and β1 integrin subunit expression when K562 cells were exposed to retinoid agonists or vehicle for 24, 48, 72 or 96 hours. Our data demonstrates no differences in K562 cell surface expression of the α5 integrin subunit when cells were exposed to RARα, RARβ, or RARγ agonists for all time points tested. In contrast, RARγ agonist exposure resulted in an increase in cell surface β1 integrin subunit expression within 48 hours that was sustained at 72 and 96 hours. Finally, we demonstrate that while exposure to RARα or RARβ agonists have no effect on K562 cellular proliferation, the RARγ agonist significantly dampens K562 cellular proliferation levels in a time- and concentration- dependent manner. Our study is the first to report that treatment with a RARγ specific agonist augments cellular adhesion to α5β1 integrin substrates, increases cell surface levels of the β1 integrin subunit, and dampens cellular proliferation in a time and concentration dependent manner in a human erythroleukemia cell line.
A Review of Psychosocial and Interpersonal Determinants of Sexuality in Older Adulthood

This brief review identifies a number of psychological, social, and interpersonal barriers to sexual expression among older adults. Cultural ideas about sexuality and aging as well as attitudes about sex are noted psychological factors that impact sexuality in older adulthood. Social factors, including the availability of a healthy partner, provide the opportunity structure for partnered sexual activity to occur. Among partnered individuals, interpersonal factors, such as sexual communication and relationship quality, impact individuals’ sexual desire, sex frequency, and sexual satisfaction. Overall, this review highlights the importance of taking a more comprehensive approach to the study of aging and sexuality. In particular, researchers should continue to integrate interpersonal aspects of sexuality in older adulthood into the traditional physiological and psychosocial models.
SOME IDEAS IN COMPUTATIONAL PROBABILITY

Publisher Summary This chapter presents some ideas in computational probability. The computers play an important role in contemporary mathematics. When computers began to be available to the academic community, their importance became obvious to workers in many fields: physics, biology, medicine, and geology. The examples of a computer's use can also be found in the social sciences, such as in statistical data analysis, and even in humanities. The mathematicians do not show the same sort of enthusiastic acceptance of the computer as a new research tool, except for isolated cases such as Lehmer's work in number theory. It is important to realize the qualitative difference between mathematics and the physical sciences. The chemistry or astronomy deals with certain aspects of the physical world, while mathematics deals with an abstract world constructed by man. The probabilist deals with logical structures and not with lots of data so that he could not be confronted with massive number crunching.
Freedom of Speech and Intellectual Property: Some Thoughts After Eldred, 44 Liquormart, Saderup, and Bartnicki

This article makes several different observations about the Free Speech Clause and intellectual property law, in light of some recent doctrinal developments: (1) the Court's decision about copyright in Eldred v. Ashcroft; (2) the Court's evolving commercial speech jurisprudence in cases such as 44 Liquormart v. Rhode Island, which is relevant to trademark dilution law; (3) the California Supreme Court's right of publicity decision in Comedy III Productions v. Saderup; and (4) the Court's decision in Bartnicki v. Vopper, which indirectly bears on trade secret law.
Transnational Spatial Dimensions of Colombian–Canadian Relations in the Era of Capitalist Expansionism

The study of the history of the Western Hemisphere, as a spatial unit, has been for the most part disregarded. In North America, historians such as Lester Langley and Herbert Bolton tried to make h...
N2 Chemistry in Interstellar and Planetary Ices: Radiation-Driven Oxidation

As part of our work on nitrogen-rich ices, the IR spectra and band strengths used in a recent paper to identify and quantify radiation-induced changes in an N2+H2O ice near 15 K are examined, along with reports of (i) a chemical tracer for N2+H2O ices, (ii) a new IR feature of solid N2, and (iii) a striking 15N isotopic enrichment. Problems are found for each IR band strength used and for each of the three claims made, to the extent that none are supported by the results presented to date. In contrast, new work presented here, combined with several older investigations, strongly supports the formation of di- and triatomic nitrogen oxides in irradiated N2-rich ices. Observations and trends in the chemistry of N2-rich icy solids are described, and conclusions are drawn. A considerable amount of material from previous chemical studies of N2-rich systems, spanning more than a century, is brought together for the rst time and used to examine the chemistry of N2-rich ices in extraterrestrial environments. Needs are identied and suggestions made for future studies of N2-rich interstellar and planetary ice analogs.
School-Based Weight Management Program Curbs Summer Weight Gain Among Low-Income Hispanic Middle School Students.

Background Research shows that elementary students gain weight over the summer. It is unknown if these findings apply to Hispanic adolescents. We evaluated school and summer standardized body mass index (zBMI) changes in Hispanic middle school students. Methods Hispanic middle school students were randomly assigned to a weight management program (N = 230) or control condition (N = 195). Paired sample t-tests compared zBMI change scores during the school year versus summer when not enrolled in a weight management program (eg, control group). We used 2 × 2 repeated measures analysis of variances to determine program group differences in zBMI scores across school versus summer periods separately for normal and overweight/obese students. Results In the control group, students' zBMI change scores decreased during the school year, but increased during summer for both normal weight and overweight/obese students. Program effects on zBMI indicated school year decreases and summer increases for both normal and overweight/obese students. However, zBMI scores did not differ by program status for normal weight students. Overweight/obese students in the program compared to the control group increased zBMI to a lesser extent over the summer. Conclusion For all students, zBMI increased during the summer. A school-based weight management program protected overweight/obese students against potentially greater summer weight gain.
Di-4-pyridylmethane-diol.

In the title compound, C11H10N2O2, individual mol­ecules lie across crystallographic twofold rotation axes. Neighboring mol­ecules engage in O—H⋯N hydrogen bonding, forming square-grid layers parallel to the ab plane.
The phosphatidylethanolamine biosynthesis pathway provides a new target for cancer chemotherapy

Background & aims Since human induced pluripotent stem cells (iPSCs) develop into hepatic organoids through stages that resemble human embryonic liver development, they can be used to study developmental processes and disease pathology. Therefore, we examined the early stages of hepatic organoid formation to identify key pathways affecting early liver development. Methods Single-cell RNA-sequencing and metabolomic analysis was performed on developing organoid cultures at the iPSC, hepatoblast (day 9) and mature organoid stage. The importance of the phosphatidylethanolamine biosynthesis pathway to early liver development was examined in developing organoid cultures using iPSC with a CRISPR-mediated gene knockout and an over the counter medication (meclizine) that inhibits the rate-limiting enzyme in this pathway. Meclizine's effect on the growth of a human hepatocarcinoma cell line in a xenotransplantation model and on the growth of acute myeloid leukemia cells in vitro was also examined. Results Transcriptomic and metabolomic analysis of organoid development indicated that the phosphatidylethanolamine biosynthesis pathway is essential for early liver development. Unexpectedly, early hepatoblasts were selectively sensitive to the cytotoxic effect of meclizine. We demonstrate that meclizine could be repurposed for use in a new synergistic combination therapy for primary liver cancer: a glycolysis inhibitor reprograms cancer cell metabolism to make it susceptible to the cytotoxic effect of meclizine. This combination inhibited the growth of a human liver carcinoma cell line in vitro and in a xenotransplantation model, without causing significant side effects. This drug combination was also highly active against acute myeloid leukemia cells. Conclusion Our data indicate that phosphatidylethanolamine biosynthesis is a targetable pathway for cancer; meclizine may have clinical efficacy as a repurposed anti-cancer drug when used as part of a new combination therapy. Lay summary The early stages of human liver development were modeled using human hepatic organoids. We identified a pathway that was essential for early liver development. Based upon this finding, a novel combination drug therapy was identified that could be used to treat primary liver cancer and possibly other types of cancer.
The impact of engineering information format on task performance: Gaze scanning pattern analysis

Abstract The emergence of new visualization technologies such as Virtual Reality (VR) and Augmented Reality (AR) had been widely implemented in the Architecture, Engineering, and Construction (AEC) industry. Although cumulative evidence pointed out a positive impact of these visualization technologies on construction task performance, there is still an obvious disagreement on the benefits or implications of these new visualization technologies, due to the lack of understanding of the mechanisms in which the visualization affects cognitive processes related to information processing. To obtain more evidence, this paper presents a human-subject experiment (n = 90) to investigate the impact of information format on the performance of an industrial pipeline maintenance task. The investigation centers around how different engineering information formats affect the attention patterns as a potential explanation for the changes in performance. A between-group experiment design was used where the participants were randomly assigned to one of the three groups (2D group, 3D group, and VR group) depending on what type of information was given to review the pipe operation instruction. After the review session, the participants were asked to perform the operation task in the virtual environment based on their memory. The results showed that the 3D and VR groups outperformed the 2D group in task performance. The analysis of eye-tracking data further indicated that the information format significantly changed the gaze scanning pattern when participants were reviewing the operational instructions. We also found that the task performance was correlated with eye-tracking features including gaze movement and pupil dilation. Our findings provided more evidence about the mechanisms in which new visualization technologies affect the attention patterns, helped resolve the current disagreement within the literature. In addition, a prediction model was proposed to use eye-tracking features to predict construction task performance.
Imaging “Thyroiditis”: A Primer for Radiologists

A variety of inflammatory disorders, generically classified as "thyroiditis," can affect the thyroid gland diffusely, generating distinctive radiographic patterns. While a precise diagnosis can seldom be made based on sonographic appearance alone, interpreting these patterns in the correct clinical and biochemical context will help support the most appropriate diagnosis. We believe that the generic term "thyroiditis" is often not helpful and often may be incorrect. Therefore, it is important for radiologists to understand the sonographic and functional correlations to provide the most appropriate differential diagnosis in their reports. This brief review is designed to provide information and guidance for radiologists when dealing with various thyroid disorders which cause diffuse changes in the thyroid and underline the pitfalls most often encountered in clinical practice.
SiO2 Is Wasted Space in Single-Nanometer-Scale Silicon Nanoparticle-Based Composite Anodes for Li-Ion Electrochemical Energy Storage

The electrode processing conditions of silicon-based composite anodes play a pivotal role in the resulting interfacial chemical speciation and, thus, the electrochemical cycling behavior of the ele...
The Conversion of Iberia’s Bells

In 997 the bells of Santiago de Compostela converted to Islam. Al-Mansur, de facto ruler of al-Andalus, destroyed the Christian shrine of Santiago de Compostela and carried off its bells to Cordoba...
Striping in large tape libraries

The authors evaluate the effectiveness of applying data striping concepts to large tape libraries, for randomly distributed access to the tape library. They believe such operations will be characteristic of future tertiary storage databases using large objects, such as online libraries and multimedia databases. Using an event-driven simulator, it is shown that striped large tape libraries perform poorly for this random workload because striping causes contention for the small number of readers and robot arms in these libraries. Increasing the number of readers results in better striped performance. The authors also examine how the effectiveness of striping may change as readers and robots improve in performance. They find that striping continues to be an effective technique for increasing the throughput of large accesses if reader and robot performance scale at similar rates.
Electronic nose system based on a functionalized capacitive micromachined ultrasonic transducer (CMUT) array for selective detection of plant volatiles

Abstract Here, a small, low-power, wireless gas sensor platform for selective detection of volatile organic compounds (VOCs) released from plants under different abiotic or biotic stress conditions is described. This sensor platform is implemented based on a capacitive micromachined ultrasonic transducer (CMUT) array, in which elements were functionalized with a variety of materials including polymers, phthalocyanines, and metals to improve selectivity. Input impedance measurements of the functionalized CMUT array were compared to pre-coating measurements to analyze the mechanical loading. The CMUT arrays were then exposed to VOCs known to be emitted by plants with different concentrations under dry air flow at room temperature. The results demonstrated that 1-Octanol created the strongest response across different channels and a resolution of 3-ppb was calculated for the CMUT element functionalized using silver ink when exposed to 1-Octanol. The relative responses of different channels to tested volatiles were observed to be different. The k-nearest neighbor (k-NN) algorithm was used for the gas classification by dividing the data to training and test groups. The k-NN results showed that the gases at low concentrations were successfully classified with better than 97 % accuracy. Finally, to emulate the ambient atmosphere for plants, the gas tests were repeated by adding different levels of humidity to the gas flow. With a minimum 98 % accuracy, the k-NN classifier demonstrated that the functionalized CMUT array can be used for selective detection of the group of plant VOCs used in this study, even at different relative humidity levels in the ambient atmosphere.
A dual voltage clamp technique to study gap junction hemichannels in astrocytes cultured from neonatal rodent spinal cords

Astrocytes express surface channels involved in purinergic signaling, and among these channels, pannexin-1 (Px1) and connexin-43 (Cx43) hemichannels (HCs) mediate ATP release that acts directly, or through its derivatives, on neurons and glia via purinergic receptors. Although HCs are functional, i.e., open and close, under physiological and pathological conditions, single channel conductance of Px1 HCs is not well defined. Here, we developed a dual voltage clamp technique in HeLa cells overexpressing human Px1-YFP, and then applied this system to rodent spinal astrocytes. Single channels were recorded in cell attached patches and evoked with ramp cycles of 2 s duration and -/+ 80-100 mV amplitude or rectangular pulses through another pipette in whole cell clamp. Conductance of Px1 HC openings recorded during ramp stimuli ranged 25-110 pS. Based on their single channel conductances, Px1 HCs could be distinguished from Cx43 HCs and P2X7 receptors (P2X7Rs) in spinal astrocytes during dual voltage clamp experiments. Furthermore, we found that single channel activity of Cx43 HCs and P2X7Rs was increased, and that of Px1 HCs was decreased, in spinal astrocytes treated for 7h with FGF-1, a growth factor implicated in neurodevelopment, repair and inflammation.
Ultrasonic Evaluation of in-Plane and out-of-Plane Elastic Properties of Composite Materials

Evaluation of elastic properties of composite materials using ultrasound is important for the generation of output data for the design of composites. It is also extremely important as a nondestructive tool for quality evaluation of the composites after manufacturing. The problem was addressed in the seventies [1–3] when Markham [1] suggested using the time-delay through transmission technique with obliquely incident ultrasonic waves from water onto a composite plate. The full set of elastic constants was measured later by Kriz and Stinchcomb [4] on samples cut out in different directions from a composite plate. Recently several works have appeared where the set of elastic constants was measured by using Markham’s technique [5–7].
Recent Advancements in Split Hopkinson Pressure Bar (SHPB) Technique for Small Strain Measurements

Recent advances in SHPB technique are discussed. A compliance calibration technique together with an exact 1-D Hopkinson bar theory has been developed to accurately measure the rate dependent elastic modulus in the small strain range. A right circular cylinder (RCC) specimen with chamfered edges is found to minimize the stress concentration at the edges and thus provide a more uniform uni-axial stress state in the specimen. A new SHPB experimental methodology using an equal diameter RCC specimen and a small diameter RCC specimen is developed in determining the dynamic stress-strain behavior of materials.
Bilateral Aid to Least Developed Countries: A Study of the U.S., the U.K., France and Japan

Bilateral aid allocation is affected by a number of factors on the donor side. It has been found that public satisfaction with government positively affects the willingness to give bilateral aid (Gradstein and Chong, 2007). Economic and strategic interests of the donor country play a role in determining bilateral aid allocation (Tingley, 2009). Perhaps the most interesting finding is that ideology has a significant impact on bilateral aid allocation (Fleck and Kilby, 2001) (Milner and Tingley, 2010). This article is available in The Park Place Economist: http://digitalcommons.iwu.edu/parkplace/vol20/iss1/18 The Park Place Economist, Volume XX 94 BILATERAL AID TO LEAST DEVELOPED COUNTRIES: A STUDY OF THE U.S., THE U.K., FRANCE, AND JAPAN
The Wolff-Parkinson-White syndrome. Report of a case with fatal arrhythmia and autopsy findings of myocarditis, interatrial lipomatous hypertrophy, and prominent right moderator band.

Abstract A case of WPW syndrome with atrial fibrillation resulting in death is presented. Autopsy revealed lipomatous hypertrophy of the interatrial septum, diffuse interstitial myocarditis, and an abnormal muscle bundle within the right ventricular cavity. A possible etiologic relationship of ventricular pre-excitation to myocardial hypertrophy is proposed. The mortality rate hazard of WPW syndrome is discussed.
Searching for the elusive targets of farnesyltransferase inhibitors

Farnesyltransferase (FTase) inhibitors (FTIs) were developed originally as anti-RAS compounds and novel target-based drugs for cancer treatment. The analyses of FTIs continue in the clinic, but the antitumour activity cannot be ascribed simply to inhibition of RAS. Although FTI action is due to inhibition of FTase, and RAS proteins are indeed substrates for this enzyme, the RAS proteins that are most frequently mutated in human cancers escape FTI inhibition. RHOB has been suggested as a target, but is this issue resolved or do the crucial targets of FTIs remain to be identified?
The prevention of deep venous thrombosis in physically restrained patients with schizophrenia

Summary Background: Physical restraint and seclusion are associated with several risks. Antipsychotic drug use increases this risk. Objective: To evaluate whether the risk of thromboembolism in physical restraint and seclusion of patients with psychosis, treated with antipsychotic medication, was considered by taking preventive measures. Method: Anonymous data on all consecutively admitted patients with schizophrenia, treated with antipsychotic medication, between 2002 and 2009, were analysed. Diagnostic information and data about seclusion procedures and medication were collected. Preventive measures of thromboembolism in patients in physical restraint were assessed by reviewing case notes and the medication prescribed at the time of seclusion. Results: Seclusion of patients with psychosis is common. Out of 679 identified patients, 170 had been secluded (472 events). Physical restraint use was not a rare event (N seclusions with restraint use 296, 62.7%). Pharmacological preventive measures (use of heparine dugs) were taken frequently to prevent deep vein thrombosis (DVT) by physical restraint or isolation. Sixty-five (38.2%) out of 170 secluded patients, including a majority of patients who had been under physical restraint, had been administered anticoagulants at the time of seclusion. No cases of DVT occurred. Conclusions: Preventive measures were routinely administered in clinical practice and were effective in the prevention of DVT. For a clinical setting, it is important to establish a clear and detailed management plan on seclusion and fixation taken into account in all possible risks of physical restraint.
Dynamical stability and parameter selection in neural optimization

Finding suitable parameter values in solving optimization problems with the Hopfield net is of crucial importance. The authors present a systematic approach, based on analyzing dynamical stability of valid solutions for finding relationships among the parameters which make their selection much easier. This technique can show whether the problem formulation is flawed. As an example they discuss the Hopfield-Tank formulation of the traveling salesman problem and show that it is dynamically unstable, hence obtaining valid solutions is difficult. The modified formulation given by S.Y.B. Aiyer et al. (1990) which overcomes the instability problems is also discussed. >
Matrix-mediated cellular rejuvenation.

Biomaterial surface morphology and chemistry influence cell responses mediated via signaling cascades that regulate a wide range of metabolic processes. These responses may range from changes in surface adhesion and remodeling of the extracellular matrix to activation of cytokine, cytoskeletal and other biochemical pathways regulating or modulating cellular morphology and function. The present study has focused on collagen Type I, a key extracellular matrix protein, and its potential impact on the process of cellular aging. This study was undertaken for several reasons. First, several investigators reported that growth of cells on a collagen matrix markedly enhanced the resistance of cells to stresses. Second, a large body of accumulated data strongly indicated a relationship between the potential to respond to stresses and cellular aging with the former strongly influencing the rate of the latter. Finally, it has been recently demonstrated that in aged cells one of the key aging-related processes previously considered irreversible, attenuation of the expression of a major stress response protein, Hsp70, can be reversed. This fact together with a probable regulatory role of the stress response potential in cellular aging suggested a possibility that the cellular aging process as a whole can be altered. Indeed, in the present study, growth on a denatured collagen matrices reversed in aged cells not only the attenuation of Hsp70 expression but also other aging-related processes, such as β-galactosidase expression, increase in protein oxidation and changes in cell morphology. Moreover, it appeared to reduce the rate of aging in young cells. Understanding the nature of collagen matrix-mediated cellular rejuvenation might suggest approaches for interfering with organismic aging. Some immediate applications include cell rejuvenation for purposes of cloning and reduction of the rate of aging during expansion of stem cells for purposes of tissue engineering.
NaI detector nonlinearity for PGNAA applications

Abstract The nonlinearity of a 6″×6″ NaI detector used for PGNAA has been measured. The prompt γ-rays from pure element samples mixed with graphite were used for this determination in the range from 1.712 to 10.829 MeV and γ-rays from radioisotope sources were used in the range from 0.356 to 1.333 MeV. A surprising result is that the pulse height per unit absorbed energy is slightly higher from single escape as opposed to full energy peaks. One explanation for this is that the light production efficiency for positrons may be different than that for electrons. By interpolation a value for the coincidence spectral full energy peak exhibited by NaI detectors that are neutron activated is obtained. The value reported is 6.885 MeV which is slightly higher than the cross section weighted value of 6.834 MeV. (The reported S N values for I and Na are 6.826 and 6.959 MeV, respectively.)
Synthesis and characterization of mixed-ligand diimine-piperonal thiosemicarbazone complexes of ruthenium(II): Biophysical investigations and biological evaluation as anticancer and antibacterial agents

We have used a novel microwave-assisted method developed in our laboratories to synthesize a series of ruthenium-thiosemicarbazone complexes. The new thiosemicarbazone ligands are derived from benzo[d][1,3]dioxole-5-carbaldehyde (piperonal) and the complexes are formulated as [(diimine)(2)Ru(TSC)](PF(6))(2) (where the TSC is the bidentate thiosemicarbazone ligand). The diimine in the complexes is either 2,2'-bipyridine or 1,10-phenanthroline. The complexes have been characterized by spectroscopic means (NMR, IR and UV-Vis) as well as by elemental analysis. We have studied the biophysical characteristics of the complexes by investigating their anti-oxidant ability as well as their ability to disrupt the function of the human topoisomerase II enzyme. The complexes are moderately strong binders of DNA with binding constants of 10(4) M(-1). They are also strong binders of human serum albumin having binding constants on the order of 10(4) M(-1). The complexes show good in vitro anticancer activity against human colon cancer cells, Caco-2 and HCT-116 and indeed show some cytotoxic selectivity for cancer cells. The IC(50) values range from 7 - 159 μM (after 72 h drug incubation). They also have antibacterial activity against Gram-positive strains of pathogenic bacteria with IC(50) values as low as 10 μM; little activity was seen against Gram-negative strains. It has been established that all the compounds are catalytic inhibitors of human topoisomerase II.
Chromatographic Fractionation of SWNT/DNA Dispersions with On-Line Multi-Angle Light Scattering

Single wall carbon nanotubes (SWNTs) dispersed in aqueous medium by the use of DNA are separated by size using a size exclusion chromatographic (SEC) column. On-line measurements are made of SWNT concentration, molar mass, and size using UV−vis absorption detection and multi-angle light scattering (MALS). Molar mass and length distributions are calculated for SWNT dispersions from this data. The SWNTs are shown to separate primarily by a SEC mechanism, but the elution times are affected by a high performance liquid chromatography (HPLC) mechanism in which adsorption on the column delays the elution of the components. This mechanism is most evident by the elution of small quantities of large, polydisperse SWNTs after the SEC column limit. MALS data are fit with a polydisperse anisotropic rod scattering function giving low polydispersity for most of the fractions with higher polydispersities near the large size exclusion limit and beyond the small size exclusion limit of the SEC column. These fits indicate ...
Modeling and design of coupled cavity for the electro-optical modulators

In this paper we presented the modeling, design of a millimeter wave (MMW) photonic modulator operating at high Giga-Hertz frequency, i.e. 94GHz. Our approach combines high quality factors (Qs) photonic microdisks with nonlinear properties of electro-optic (EO) material at the present of applied millimeter wave to achieve optical modulation. The high Q values and strong field densities associated with WGMs in microdisk resonators result in the enhancement of the nonlinear interaction of optical fields with a material that exhibits coherent attributes, even with weak millimeter waves. The coupled mode theory (CMT) is applied to incorporate the nonlinearity of EO material in the optical analysis. In the simulations, two EO materials, LiNBO3 and GaAs, are considered and designed to realize the MMW photonic modulation. In addition, carefully design and analysis is taken by using rigorous electromagnetic (EM) algorithm to accurately determine EM field in the MMW resonator, which will provide maximum modulation.
A discrete damage zone model for mixed-mode delamination of composites under high-cycle fatigue

A discrete damage zone model is developed to describe the mode-mix ratio and temperature dependent delamination of laminated composite materials under high cycle fatigue loading within the framework of the finite element method. In this approach, discrete nonlinear spring elements are placed at the finite element nodes of the laminate interface, and a combination of static and fatigue damage growth laws is used to define its constitutive behavior. The model is implemented in the commercial software Abaqus using the user element subroutine. The static damage model parameters are estimated from fracture mechanics principles, whereas the fatigue damage model parameters are calibrated by fitting the numerical results to published experimental data. A quadratic relation is proposed to describe the non-monotonic variation of fatigue damage model parameters with mode-mix ratio. Next, an Arrhenius relation is proposed for the temperature dependence of fatigue damage, in addition to the incorporation of the temperature dependence of critical fracture energy. The model is convergent upon mesh refinement; however, for accurate prediction the mesh size used for model calibration should be sufficiently small. The model predicted fatigue crack growth rates are in agreement with those obtained from a quadratic relation for the Paris law parameters for variable mode mix conditions, thus verifying the approach. While the model captures the temperature effects on delamination for mode I and 50 % mode II, our prediction deviates from experiments for pure mode II, since the corresponding damage mechanism entirely changes with temperature.
The Effect of Microdiet Supplementation of Dietary Digestive Enzymes and a Hormone on Growth and Enzyme Activity in Yellow Perch Juveniles

Abstract Juvenile yellow perch Perca flavescens were evaluated to assess their needs for exogenous digestive enzyme and hormone supplementation in dry diets. Evidence exists to support the hypothesis that these supplements may assist young fish in digestion. Four diets were tested: A commercially available trout starter; an experimental diet based on high quality fish meals and squid meal; and the experimental diet supplemented with either 0.1% (by weight) bombesin (digestive tract neurohormone) or pancreatin (digestive enzyme extract). Fish fed all diets had similar growth. Survival was high and was not significantly different between treatments. Specific activities for both trypsin and chymotrypsin were not significantly different between diets, indicating that digestive enzyme supplementation was not necessary in tested juveniles. Specific activities for pepsin were also not significantly different between treatments, indicating supplementation of dry diets with the digestive hormone bombesin did not a...
Time after time: environmental influences on the aging brain.

The population of Americans aged 65 and older is expected to double between 2010 and 2050,1 and by midcentury the proportion of the human population made up of people over age 80 is projected to have quadrupled since 2000.2 So factors that affect this aging population are of increasing importance. Of particular concern are the neurological diseases and disorders typically associated with advanced age, among them Alzheimer’s and Parkinson’s diseases, dementia, and reduced cognitive function. Investigators are studying the effects of not just present-day exposures and environmental influences such as physical and mental exercise, but also exposures that occurred much earlier in life, whose effects may only become apparent in old age. A growing body of evidence suggests that neurological function in the elderly can be affected by exposures from years earlier. It was long assumed that “once the brain received its allotted quota of nerve cells, its destiny was frozen. After that, the passage of time eroded our allotment steadily and irrevocably,” as professor emeritus Bernard Weiss of the University of Rochester School of Medicine and Dentistry wrote in 2007.3 Now, however, there is increasing evidence that the brain is capable of generating new neurons and other functional brain cells even during advanced age. There is also evidence that the older brain can respond quickly and positively to external influences such as physical exercise and intellectual stimulation. This is prompting considerable interest in developing strategies for protecting and enhancing neurological function in the elderly. The two most vulnerable periods for the brain, Weiss says, are early in life, when the organ is first developing, and later in life, when the body’s defenses and compensatory mechanisms begin to falter. There is a large and growing body of evidence indicating these two vulnerable life stages can be linked when damage incurred during early development contributes to health disorders that may not become apparent until later in life.4 Weiss also notes that declining defense mechanisms may magnify vulnerability to contemporary environmental exposures. He says that when older adults experience cognitive problems, diagnoses rarely consider the possibility that environmental chemical exposure may be involved, simply because questions about such exposures are typically not asked as part of clinical intake. Over the past 30 years, Weiss says, research attention has focused primarily on environmental influences on early developmental stages. Far less extensively researched, but a subject of increasing interest, are environmental chemical exposures that can affect the health of the aging brain.
Non-Insulin-Mediated Glucose Disappearance in Subjects With IDDM: Discordance Between Experimental Results and Minimal Model Analysis

Both insulin and glucose contribute to the regulation of glucose metabolism in vivo. We directly measured the ability of glucose per se to promote glucose disposal in subjects with insulin-dependent diabetes mellitus (IDDM). We compared our results with predictions of the minimal model of glucose metabolism. To identify minimal model parameters, a frequently sampled intravenous glucose tolerance test (FSIVGTT) was administered to each subject while they were connected to a Biostator (a device that monitors blood glucose and gives insulin to mimic normal insulin secretion). Data from this test reflected normal glucose tolerance and were in excellent agreement with minimal model predictions. The FSIVGTT was then repeated without the Biostator in the same diabetic subjects in order to directly measure the effect of glucose per se to promote glucose disposal in the absence of an incremental insulin effect (a basal insulin drip was maintained). To compare these results with minimal model predictions, the equations describing glucose disappearance in the absence of an incremental insulin effect were solved using parameters identified from the Biostator experiment. The glucose disappearance measured in the absence of an incremental insulin response was much slower than the minimal model predictions. Thus, the minimal model appears to overestimate the effect of glucose per se on glucose uptake and underestimate the contribution of incremental insulin.
Atmospheric Science Measurements by the EOS Geoscience Laser Altimeter System

Scheduled for Launch in July 2001, the Geoscience Laser Altimeter System (GLAS) is to be the first satellite instrument to provide full global lidar profiling of clouds and aerosol in the earth's atmosphere. GLAS is an EOS program instrument that is on its own satellite, now called the Ice, Cloud and land Elevation Satellite. The instrument is both a surface laser ranging system and an atmospheric profiling lidar. A most important surface measurement for the instrument is to study the change in the mass balance of the polar ice sheets by measuring the change in regional altitudes to an accuracy of 1.5 cm per year. The strategy to combine the surface measurement with a Cloud and aerosol lidar profiling mission is based on the compatibility of the altimetry instrument requirements with those for the required lidar measurements. The primary atmospheric science goal of the GLAS cloud and aerosol measurement is to determine the radiative forcing and vertically resolved atmospheric heating rate due to cloud and aerosol by directly observing the vertical structure and magnitude of cloud and aerosol parameters that are important for the radiative balance of the earth-atmosphere system, but which are ambiguous or impossible to obtain from existing or planned passive remote sensors. A further goal is to directly measure the height of atmospheric transition layers (inversions) which are important for dynamics and mixing, the planetary boundary layer and lifting condensation level.