cssi/SciSciGPT-SciSciNet huggingface dataset:
Structure-Based Design and Synthesis of Benzothiazole Phosphonate Analogues with Inhibitors of Human ABAD-Aβ for Treatment of Alzheimer’s Disease

Amyloid binding alcohol dehydrogenase, a mitochondrial protein, is a cofactor facilitating amyloid-β peptide (Aβ) induced cell stress. Antagonizing Aβ-ABAD interaction protects against aberrant mitochondrial and neuronal function and improves learning memory in the Alzheimer's disease mouse model. Therefore, it offers a potential target for Alzheimer's drug design, by identifying potential inhibitors of Aβ-ABAD interaction. 2D QSAR methods were applied to novel compounds with known IC(50) values, which formed a training set. A correlation analysis was carried out comparing the statistics of the measured IC(50) with predicted values. These selectivity-determining descriptors were interpreted graphically in terms of principle component analyses, which are highly informative for the lead optimization process with respect to activity enhancement. A 3D pharmacophore model also was created. The 2D QSAR and 3D pharmacophore models will assist in high-throughput screening. In addition, ADME descriptors were also determined to study their pharmacokinetic properties. Finally, amyloid binding alcohol dehydrogenase molecular docking study of these novel molecules was undertaken to determine whether these compounds exhibit significant binding affinity with the binding site. We have synthesized only the compounds that have shown the best drug-like properties as candidates for further studies.
The Enlightened Era of Enterprise Security (Invited Talk)

The more money and resources we seem to throw at security, the more the bad guys seem to catch up. With every new technology innovation, comes a new --- and sometimes worse --- threat to your business. It simply comes in a different form.
Single crystal silicon MEMS fabrication technology using proton-implantation smart-cut technique

A novel single crystal silicon MEMS fabrication process is proposed using proton-implantation smart-cut technique. Compared to conventional SOI wafer fabrication processes for MEMS applications, this technology can potentially result in a significant substrate and processing cost reduction. A single crystal silicon layer with 1.78 /spl mu/m thickness has been achieved using the proposed technique. Prototype structures such as cantilever beams and clamped-clamped micro-bridges have been successfully fabricated as demonstration vehicles for future micro-system implementations.
Quilting a Field Pattern Portrait Using Butcher’s Methodology

The nursing profession acknowledges Martha Rogers to the foundation of nursing theory as a true visionary. Butcher developed a method that ensures scientific rigor in the application of Rogerian theory, unitary field pattern portrait (UFPP), which was used to explore new phenomenon of inquiry resulting in insights into Rogerian pandimensionality. In this intervention, an American Indian tradition, quilting, became a culturally appropriate way for a nurse to facilitate healing through the application of Rogerian theory. In Rogers's theory of the science of unitary human beings, pattern unfolding becomes a way of knowing through expansion, evolving, blossoming, revealing, and openness. Rogers's theory was used to encourage healing as an American Indian mother and deeply depressed daughter created a quilting story based on Rogerian principles: resonancy, helicy, and integrality. This aesthetic field patterning modality using Butcher's UFPP captured the intervention as clients were engaged in health patterning through the American Indian tradition of quilting. Field notes with reflective journaling as recommended by Butcher assisted in the crystallization of a UFPP drawn from Rogerian nursing theory.
Impaired neural structure and function contributing to autonomic symptoms in congenital central hypoventilation syndrome

Congenital central hypoventilation syndrome (CCHS) patients show major autonomic alterations in addition to their better-known breathing deficiencies. The processes underlying CCHS, mutations in the PHOX2B gene, target autonomic neuronal development, with frame shift extent contributing to symptom severity. Many autonomic characteristics, such as impaired pupillary constriction and poor temperature regulation, reflect parasympathetic alterations, and can include disturbed alimentary processes, with malabsorption and intestinal motility dyscontrol. The sympathetic nervous system changes can exert life-threatening outcomes, with dysregulation of sympathetic outflow leading to high blood pressure, time-altered and dampened heart rate and breathing responses to challenges, cardiac arrhythmia, profuse sweating, and poor fluid regulation. The central mechanisms contributing to failed autonomic processes are readily apparent from structural and functional magnetic resonance imaging studies, which reveal substantial cortical thinning, tissue injury, and disrupted functional responses in hypothalamic, hippocampal, posterior thalamic, and basal ganglia sites and their descending projections, as well as insular, cingulate, and medial frontal cortices, which influence subcortical autonomic structures. Midbrain structures are also compromised, including the raphe system and its projections to cerebellar and medullary sites, the locus coeruleus, and medullary reflex integrating sites, including the dorsal and ventrolateral medullary nuclei. The damage to rostral autonomic sites overlaps metabolic, affective and cognitive regulatory regions, leading to hormonal disruption, anxiety, depression, behavioral control, and sudden death concerns. The injuries suggest that interventions for mitigating hypoxic exposure and nutrient loss may provide cellular protection, in the same fashion as interventions in other conditions with similar malabsorption, fluid turnover, or hypoxic exposure.
Issues in Algebraic Control Theory

A unified view of recent results in the algebraic theory of linear, time-invariant multiinput-multioutput control systems is presented, with emphasis on the unity-feedback system (one-degree-of-freedom design) and the more general two-input two-output plant and compensator configuration (four-degrees-of-freedom design). The issues of stability, parametrization of all stabilizing compensators, achievable input-output maps and decoupling are discussed.
Change-point Methods in Statistical Process Control†

Change-point methodologies applied to statistical process control are predicated on the possibility that a special cause induces a shift from an in-control statistical model to an out-of-control statistical model, and so are particularly attractive for persistent special causes. Along with indications of a loss of control, they provide estimates of when the shift occurred, and (if needed) of the before- and after-shift process parameters. A less obvious advantage is that some change-point proposals allow for the near-universal situation that the in-control distribution of process readings is not known exactly. This feature largely removes the need for extensive phase I calibration studies, and allows phase II production use to start early. In addition to the stand-alone use of change-point methodologies for both signaling and diagnosing the effects of special causes, they have been proposed as tools for following up signals given by other charting methods, when their likelihood properties lead to good estimators of the time of occurrence and effect of the special cause. Keywords: change point; LRT ; GLR ; phase I; phase II; SPC
Developmental correlation of higher levels of estrogen binding by macromolecules in rat liver supernatant and of increases in plasma renin substrate levels after estrogen administration.

Abstract The adult female liver supernatant contains a high affinity estrogen specific binding protein. The liver of the prepubescent female rat has less estrogen specific binding macromolecules than the adult. This difference in quantity is maintained when binding activities are partially purified by precipitation with ammonium sulfate at 30% saturation. After administration in vivo of ethinyl estradiol, plasma renin substrate (PRS) levels increase 167 per cent above control in the adult female rat. The corresponding increase is only 15 per cent in the prepubescent rat. In contrast, renin substrate levels are markedly increased in both the prepubescent and adult by administration of the glucocorticoid, dexamethasone. The substantial increase in the amount of estrogen binding and PRS responsiveness to estrogen administration with sexual maturation suggests that the estrogen binding protein may be an estrogen receptor involved in modulating synthesis of at least one plasma protein.
Temperature and irradiating species effects on the critical amorphization dose in NiAl3

Thin film samples of NiAl 3 have been used to examine the effects of sample temperature and mass of the irradiating species on the crystalline to amorphous transformation. Irradiations were carried out at 100 K and 300 K using 300 keV Xe, 60 keV Ne, and 1 MeV electron. At 100 K the NiAl 3 phase was completely transformed into an amorphous solution between = 0.30 and 0.40 displacements per atom (dpa) for Xe, Ne, and electrons. At 300 K only Xe irradiation produced a complete transformation to the amorphous state between 0.40 and 0.50 dpa; Ne irradiations only partially amorphized the NiAl 3 phase while electron irradiated NiAl 3 remained crystalline and ordered. These results suggest that the critical damage dose for amorphization is independent of the irradiating species at low temperature and that the critical amorphization temperature is irradiating species dependent. There is reasonable agreement between the experimental amorphization dose and the dose predicted by a cascade model suggesting that a direct transformation mechanism may be operating during low temperature ion irradiation.
A near-Earth Asteroid Population Estimate From the LINEAR Survey

I estimate the size and shape of the near-Earth asteroid (NEA) population using survey data from the Lincoln Near-Earth Asteroid Research (LINEAR) project, covering 375,000 square degrees of sky and including more than 1300 NEA detections. A simulation of detection probabilities for different values of orbital parameters and sizes combined with the detection statistics in a Bayesian framework provides a correction for observational bias and yields the NEA population distribution as a function of absolute magnitude, semi-major axis, eccentricity, and inclination. The NEA population is more highly inclined than previously estimated, and the total number of kilometer-sized NEAs is 1227−90 +170 (1σ).
Alpha2-adrenoceptor agonists in the management of chronic pain

Abstract The rationale and potential use of α 2 -agonists in the management of chronic pain is discussed, along with a review of the literature. Most published reports describe the spinal or epidural administration of clonidine. The oral administration of α 2 -agonists such as tizanidine has also proved effective in the management of spinal spasticity. Pre-clinical data suggests that spinal α 2 -agonists may be a useful alternative when spinal opioid tolerance develops because of the relative lack of cross-tolerance between these two drug classes. The published experience with chronic neuraxial administration of α 2 -agonists is limited to a few studies of chronic epidural administration in cancer patients and some case reports of chronic intrathecal administration in non-cancer pain patients. Approved in the USA for epidural administration in cancer patients with intractable pain, the epidural administration of clonidine appears to be safe given the lack of reported toxicity in animals and in human bolus dose studies. There is still, however, a lack of clinical data to assess toxicity during chronic intrathecal infusion. The principal advantages of clonidine over spinal morphine appear to be its potential, efficacy in some neuropathic pain states, a different side-effect profile and a lack of cross-tolerance to morphine. Further clinical studies are required to explore further its potential in this regard and establish a lack of toxicity during chronic intrathecal administration.
Sexism and Handicapism in Interpersonal Helping

Summary In a factorially designed field study, two female and two male confederates (Cs) encountered 320 male and 320 female street pedestrians asking for help. Factors manipulated included sex of C, sex of Ss, handicap condition of C, dress condition of C, and the use of a wedding band to connote C's marital status. Results showed that women were helped more than men and that handicapped were helped more than nonhandicapped. Interaction effects suggest that women and the handicapped share a single category in terms of meriting and requiring increased assistance. It is argued that such overhelping is symptomatic of underlying social prejudice against women and the handicapped.
Haematological response of dogs to canine recombinant granulocyte colony stimulating factor (rcG-CSF)

Three beagle dogs were given 5 μg canine recombinant granulocyte colony stimulating factor (rcG-CSF)/kg/day for 42 days. One day after the first dose the neutrophil count exceeded the pretreatment counts by 3- to 4-fold. A steady and rapid increase occurred during days 1 to 12. In two of the dogs the counts continued to increase, but at a slower rate, from day 14 to 28. The neutrophil count in the third dog decreased steadily from day 14 to 28, although the count remained above those of the presample period and exceeded the reference range for dogs established at the Veterinary Medical Teaching Hospital, University of California, Davis. After day 28 that dog had a rapid increase in neutrophil count that reached similar numbers to the other two dogs at 34 days. At no time was a significant left shift found, although an occasional band neutrophil was observed. In addition, a moderate increase in lymphocyte and monocyte counts were found. The degree of these increases was much less than that of the neutrophils. The leukocyte counts decreased rapidly after the last dose, and 10 days later the counts were similar to those of the pretrial period.
Preliminary Safety, Pharmacokinetics, and Efficacy of Regorafenib, Cisplatin, and Pemetrexed in Patients With Advanced Nonsquamous Non-Small-Cell Lung Cancers.

Abstract Background The combination of bevacizumab, an antiangiogenesis agent, with cytotoxic chemotherapy improves survival in patients with advanced nonsquamous non–small-cell lung cancers (nsNSCLCs). Regorafenib is an oral multitargeted kinase inhibitor with potent antiangiogenic activity that is approved for patients with advanced colorectal cancer and gastrointestinal stromal tumors. In this phase I trial we evaluated the safety, pharmacokinetics (PK), and efficacy of regorafenib with cisplatin and pemetrexed for patients with advanced nsNSCLCs. Patients and Methods Chemotherapy-naive patients with advanced nsNSCLCs were treated with regorafenib 60 mg/d continuously and cisplatin 75 mg/m2 with pemetrexed 500 mg/m2 once every 21 days for up to 6 cycles. Thereafter, regorafenib with or without pemetrexed could be continued as maintenance. Results Nine patients enrolled before premature termination of the study because of slow recruitment and a change in the development strategy of regorafenib by the study sponsor. Five patients experienced at least 1 treatment-related Grade 3 adverse event. No Grade 4 or 5 toxicity occurred. Five of 9 (56%) patients had a partial response and the median progression-free survival was 7 months (range, 1.5-15.1 months). Minor PK interactions between regorafenib and chemotherapy were observed. Conclusion Regorafenib had acceptable tolerability and minor PK interactions in combination with standard doses of cisplatin and pemetrexed in patients with advanced nsNSCLCs. Encouraging activity was appreciated in chemotherapy-naive patients with advanced nsNSCLCs. However, the small number of patients treated limits conclusions that can be drawn from these results.
Atomistic Characterization of the HIV Capsid from Molecular Dynamics Simulations

The HIV capsid is large, containing about 1,300 proteins with altogether 4 million atoms. Although the capsid proteins are all identical, they nevertheless arrange themselves into a largely asymmetric structure. The large size and lack of symmetry pose a huge challenge to studying the chemical details of the HIV capsid. Simulations of 64 million atoms for over 1 micro­ second allow us to conduct a comprehensive study of the physical properties of the entire HIV capsid including electrostatic potential, all­atom normal modes, as well as the effects of the solvent (ions and water) on the capsid. The results from the simulations reveal critical details of the capsid protein with important implications for assembly, uncoating and nuclear import.
Quantum walks based on an interferometric analogy

There are presently two models for quantum walks on graphs. The ``coined'' walk uses discrete-time steps, and contains, besides the particle making the walk, a second quantum system, the coin, that determines the direction in which the particle will move. The continuous walk operates with continuous time. Here a third model for quantum walks is proposed, which is based on an analogy to optical interferometers. It is a discrete-time model, and the unitary operator that advances the walk one step depends only on the local structure of the graph on which the walk is taking place. This type of walk also allows us to introduce elements, such as phase shifters, that have no counterpart in classical random walks. Several examples are discussed.
Design of an Ankle Rehabilitation Device Using Compliant Mechanisms

In this paper, we present the design, analysis, and testing of an ankle rehabilitation device (ARD), the purpose of which is to improve the efficacy of ankle joint complex (AJC) injury diagnosis and treatment. The ARD enables physicians to quantitatively measure the severity of an injury. This is done by measuring deficiencies in the joint’s range of motion, as well as force, torque, and power output. Evaluation of the relative degree of recovery over time can also reduce the error associated with current methodologies for rehabilitation, which rely on measurements based on the patient’s verbal response. A Wheatstone bridge circuit is used for the measurement of the various parameters as applied to the blades of complementary rotational flexures; the device is designed to measure motion about three axes of rotation in the ankle joint: pitch, roll, and yaw. A full bridge circuit is applied to each axis of rotation, and the use of multiple axes increases anatomically accurate measurement, enabling characterization of coupled motions. The device has flexibility and a range of motion such that it can be adjusted to take measurements of multiple different degrees of plantar or dorsiflexion of the AJC. The ARD is able to measure both range of motion, force, and torque output simultaneously. Experimental results show that there is significant coupled motion among the ankle joint rotations but that it is highly dependent on a subject’s own physical development.
Hookworm and poverty.

Human hookworm infection is the leading cause of anemia and undernutrition and the second most important parasitic infection of humans. Hookworm occurs almost exclusively in the setting of rural poverty in the developing countries of the tropics. The rural dependency reflects the precise soil and temperature requirements of the environmental life history stages of the parasite, whereas the relationship between hookworm and poverty is based on multiple factors, including inadequate sanitation, the absence of concrete floors in home dwellings, and lack of access to essential medicines. Also, hookworm not only occurs in the setting of poverty but also promotes poverty because of its health and educational effects in children, its adverse effect on pregnancy outcome, and its effect on worker productivity. Since the middle of the 20th century, poverty reduction and urbanization have successfully reduced the prevalence of hookworm in the world's industrialized nations and some middle-income countries. However, the control of hookworm in low-income countries still relies heavily on the frequent and periodic use of anthelminthic drugs either through deworming programs targeting school-aged children or through integrated control programs that simultaneously target the seven neglected tropical diseases, including hookworm. However, the high rates of hookworm reinfection and the possible emergence of drug resistance will ultimately require the development of new control tools—including the Human Hookworm Vaccine, one of several so-called antipoverty vaccines that could undergo development and testing over the next decade.
Analysis of DNA replication intermediates suggests mechanisms of repeat sequence expansion

We previously developed a system to investigate the mechanism of repeat sequence expansion during eukaryotic Okazaki fragment processing. Upstream and downstream primers were annealed to a complementary template to overlap across a CAG repeat region. Annealing by the competing primers lead to structural intermediates that ligated to expand the repeat segment. When an equal number of repeats overlapped on the upstream and downstream primers, a 2-fold expansion was expected, but no expansion occurred. We show here that such substrates do not expand irrespective of their repeat length. To reveal mechanism, we tested different hairpin loop intermediates expected to form and facilitate ligation. Substrates configured to form large loops in either the upstream or downstream primer alone allowed expansion. Large or small fixed position single loops allowed expansion when located at least six nucleotides up- or downstream of the nick. Fixed loops in both primers, simulating a double loop intermediate, allowed expansion as long as each loop was nine nucleotides from the nick. Thus, neither the double loop configuration required to form with equal length overlaps nor the large single loop configuration are fundamental structural impediments to expansion. We propose a model for the expansion mechanism based on the relative stabilities of single loop, double loop, hairpin, and flap intermediates that is consistent with the observed expansion efficiency of equal and unequal overlap substrates. The model suggests that the equilibrium concentration of double loop intermediates is so vanishingly small that they are not likely contributors to sequence expansion.
The biosynthesis of ubiquinone in isolated rat heart cells.

Beating heart cells were isolated from the adult rat and the biosynthesis of ubiquinone was studied. These cells were able to incorporate p-hydroxy[U-14C]benzoate into ubiquinone and some unidentified compounds, presumably intermediates in the biosynthesis of ubiquinone. The unidentified compounds were labile to alkali and were also labeled by [5-3H]-mevalonate and [methyl-3H]methionine, but not by p-hydroxy[carboxy-14C]benzoate. They appear to be chromatographically different from 5-demethoxy ubiquinone and 5-desmethyl ubiquinone. Addition of unlabeled mevalonate stimulated the incorporation of p-hydroxy [U-14C]benzoate into ubiquinone and the other compounds. The addition of dimethylsulfoxide to the isolated cells or the isolation medium caused inhibition of ubiquinone biosynthesis. Adriamycin was not inhibitory to the biosynthesis of ubiquinone in the cells. The advantages of these cells are the rapidity and ease in studying the biosynthesis of ubiquinone from various precursors and its regulation.
Cost analysis of endovenous catheter ablation versus surgical stripping for treatment of superficial venous insufficiency and varicose vein disease

Background Due to its clinical efficacy and faster recovery, endovenous catheter ablation has become the treatment of choice over surgical intervention for patients with varicose veins secondary to saphenous vein reflux. Methods A retrospective analysis of costs was performed on patients undergoing vein stripping, endovenous radiofrequency ablation (RFA), endovenous laser treatment (EVLT), and phlebectomy of varicosities at a community hospital and a tertiary care hospital in southeastern Michigan. Results In 2010 to 2011, higher costs resulted in a net loss per case for vein stripping, RFA, and phlebectomy procedures performed in the operating room for the community hospital. In contrast, RFA, EVLT, and phlebectomy procedures performed in an office setting resulted in a net profit for the tertiary care institution. Conclusions Treatment of saphenous vein reflux and varicose vein disease with vein stripping was associated with higher costs than RFA and EVLT. Endovenous RFA performed in the operating room is associated with net loss per case vs office-based interventions. At present, catheter-based interventions in an office setting can be considered the more cost-effective method for treating patients with superficial venous reflux and varicose veins.
Application of dynamic programming to optimisation of hydroelectric/steam power-system operation

The paper discusses the computational aspects in the application of dynamic programming to the schedule of generation among hydroelectric and steam units in a power system for minimum operating cost. An attractive feature of this method is its ability to handle restrictions upon problem variables, such as limits upon hydroelectric plant discharge and river elevation.A computation algorithm is presented. In order to avoid excessive computer requirements, an iterative method of solution is developed using a series of grids or meshes with increasingly smaller distances between its points. A coarse grid will cover the major portion of the available operating space. The next grid points are located around the optimum solution found with the previous grid. The convergence behaviour for a chosen example is numerically analyzed. It is found that the solution is almost unique with respect to the optimum cost of operation. The optimum trajectory itself is dependent upon the location of the first grid in the available space.In any series of iterations, a solution with an accuracy of practical value would require four or more iterations. Typical convergence behaviour of both the trajectory and the return function are demonstrated from computer experiments. The paper also discusses some aspects of the use of the method for online control purposes.
Treatment of Co-Occurring Child Maltreatment and Substance Abuse

Despite high prevalence and severe negative consequences of child maltreatment (e.g., Brown, G. R., and Anderson, B., (1991). Psychiatric morbidity in adult inpatients with childhood histories of sexual and physical abuse. American Journal of Psychiatry, 148, 55-61; Jaudes, P. K., Ekwo, E., and Van Voorhis, J.V., (1995). Association of drug abuse and child abuse. Child Abuse and Neglect, 19, 1065-1075; Murphy, J. M., Jellinek, M., Quinn, D., Smith, G., and Goshkom, M., (1991). Substance abuse and serious child mistreatment: Prevalence, risk, and outcome in a court sample. Child Abuse and Neglect, 15, 197--211), the treatment of perpetrators and victims of child abuse and neglect remains grossly understudied (Behl, L. E., Conyngham, H. A., and May, P. F., (2003). Trends in child maltreatment literature. Child Abuse and Neglect, 27, 215-229). More than half of parentes founded for the abuse and neglect of their children have evidenced drug abuse, yet no treatments have been validated that concurrently address these problems. The reciprocal interaction between substance abuse and child maltreatment supports the need to concurrently treat these problems. This article illustrates the relationship between child maltreatment and parental substance abuse and proposes a behavioral model to explain the reciprocal influence of drug abuse and child maltreatment. A behavioral treatment plan that is designed to concurrently address drug abuse and child abuse is proposed and suggestions are made for future directions in this area.
Axis Curvature and Ligand Induced Bending in the CAP-DNA Oligomers

The origin of DNA axis curvature in complexes of the catabolite activator protein with DNA is studied using multiple molecular dynamics (MD) simulations of the free and protein-bound forms of the DNA. The results are compared to available solution and crystal structure data. The MD simulations reproduce the experimentally observed bend in DNA and indicate that ∼40% of the bending observed in the complex is intrinsic to the DNA sequence, whereas ∼60% is induced on protein binding. The MD provides a model for the dynamical structure of the DNA free in solution and for ligand-induced bending.
Method for Calculating Collision Probability Between a Satellite and a Space Tether

A method for calculating the collision probability between an orbiting object and a space tether, given the respective state vectors and error covariance matrices, has been developed. The methodology employs an efficient computational scheme that was used successfully in predicting the collision hazard for asymmetrical satellites. The tether is modeled as a very long, slender body having a predefined serpentine shape with a circular cross section. The colliding space object is assumed to be spherical in shape. Analytical techniques are used to reduce the collision prediction problem to that of integrating a two-dimensional symmetric probability density over a region representing the collision cross section of the tether and space object. The symmetric form of the probability density enables the two-dimensional integral to be reduced to a one-dimensional path integral that permits easy numerical implementation. Test case results indicate collision probabilities significantly higher than satellite-satellite collision probabilities.
Inequalities for bivariate distribution with x ≤ y and marginals given

Upper and lower bounds on the joint bivariate distribution are found when the marginals are given and under the additional condition that X ≤ Y with probability one. The upper bound is the same as for the unrestricted bivariate distribution with marginals given, For the lower bound a simple inequality is derived which is exact, that is, achievable, in many cases including normal and exponential marginals.
Comparison of QTLs for seed germination under non-stress, cold stress and salt stress in tomato

The purpose of this study was to examine whether rate of tomato seed germination under non-stress, cold-stress and salt-stress conditions was under similar genetic control by identifying and comparing quantitative trait loci (QTLs) which affect germination rate under these conditions. A fast-germinating accession (LA722) of the wild tomato species Lycopersicon pimpinellifolium Jusl. and a slow-germinating cultivar (NC84173, maternal and recurrent parent) of tomato (Lycopersicon esculentum Mill.) were hybridized and BC 1 and BC 1 S 1 progeny produced. The BC 1 population was used to construct a linkage map with 151 restriction fragment length polymorphism (RFLP) markers. The BC 1 S 1 population (consisting of 119 BC 1 S 1 families) was evaluated for germination under non-stress (control), cold-stress and salt-stress conditions and the mean time to 50% germination (T50) in each treatment was determined. Germination analyses indicated the presence of significant (P < 0.01) phenotypic correlations between T50 under control and cold stress (r = 0.71), control and salt stress (r = 0.58) and cold stress and salt stress (r = 0.67). The QTL analysis indicated the presence of genetic relationships between germination under these three conditions: a few QTLs were identified which commonly affected germination under both stress- (cold-, salt- or both) and non-stress conditions, and thus were called stress-nonspecific QTLs. A few QTLs were also identified which affected germination only under cold or salt stress and thus were called stress-specific QTLs. However, the stress-nonspecific QTLs generally exhibited larger individual effects and together accounted for a greater portion of the total phenotypic variation under each condition than the stress-specific QTLs. Whether the effects of stress-nonspecific QTLs were due to pleiotropic effects of the same genes, physical linkage of different genes, or a combination of both could not be determined in this study. The results, however, indicate that the rate of tomato seed germination under different stress and non-stress conditions is partly under the same genetic control.
A librational entropy mechanism for elastomers with repeating peptide sequences in helical array

A librational entropy mechanism is proposed for the elastomeric polypentapeptide of elastin which derives from the particular properties of a previously described dynamic β-spiral structure comprised of the repeating pentamer sequence. Using a cutoff energy of 2 kcal/mol residue, it is shown that the number of conformational states accessible to a single pentamer segment without perturbing the rest of the β-spiral is large in the relaxed state but becomes greatly decreased on extension. With use of the Boltzmann relation, it is seen that the effect of identical repeating units in a dynamic β-spiral is to linearly increase the entropy as the chain length increases. This occurs in spite of the valyl and prolyl side chains that significantly limit the states of the polymer and the Pro-Gly sequence which inserts a flexible β-turn. The aggregated states of the dynamic β-spiral with their weak hydrophobic intermolecular interactions that occur at high concentrations of chains and at physiologic temperatures are presented as an effective means of avoiding the entanglements that can limit numbers of accessible states for a concentrated random tangle of chains. Thus, a new mechanism is presented for an entropic elastomer which does not require that the relaxed state be totally random.
A simple batch epidemic process

Abstract A simplifying assumption for an epidemic process is that at most one person may become infected at any one time. However, it is quite conceivable that when an infected person makes simultaneous contact with two people, both could become infected. In this note we introduce the concept of a batch epidemic process in which infection can occur in batches of one or two. The distribution of the number of infectives present at any time is derived. The concept can be extended to include batches of any size.
Determination of kinetic parameters related to the piasmid instability: For the recombinant fermentation under repressed condition

The plasmid stability under the repressed state of cloned gene was studied theoretically as well as experimentally using recombinant E. coli K12DeltaH1Deltatrp/pPLc23trpA1 as a "host-vector" model system. The important kinetic parameters studied were the plasmid loss rate (theta) describing the rate at which the plasmid-harboring cells lose plasmids and the plasmid-free cells are generated per unit time and the difference in growth rates (Delta) between the two genotypes. These parameters were carefully defined, studied, and compared with other key kinetic parameters involved in the recombinant fermentation to further our understanding of metabolism of recombinants. The ratio of the concentration of plasmid-free cells to plasmid-harboring cells (Omega) was introduced, and the mathematical model was derived and used for the determination of the kinetic parameters associated with plasmid instability. These methods developed based on the theoretical considerations were tested experimentally. The results of these methods were compared, and the best method was selected and recommended. The effect of temperature and dilution rate on kinetic parameters theta and Delta were also studied in continuous culture, in order to provide some practical information related to the operation and control of recombinant fermentation processes.
Crack propagation testing using a YCOB acoustic emission sensor

Piezoelectric crystals are popular for passive sensors, such as accelerometers and acoustic emission sensors, due to their robustness and high sensitivity. These sensors are widespread in structural health monitoring among civil and industrial structures, but there is little application in high temperature environments (e.g. > 1000°C) due to the few materials that are capable of operating at elevated temperatures. Most piezoelectric materials suffer from a loss of electric properties above temperatures in the 500-700°C range, but rare earth oxyborate crystals, such as Yttrium calcium oxyborate (YCOB), retain their piezoelectric properties above 1000 °C. Our previous research demonstrated that YCOB can be used to detect transient lamb waves via Hsu-Nielsen tests, which replicate acoustic emission waves, up to 1000°C. In this paper, YCOB piezoelectric acoustic emission sensors were tested for their ability to detect crack progression at elevated temperatures. The sensor was fabricated using a YCOB single crystal and Inconel electrodes and wires. The sensor was mounted onto a stainless steel bar substrate, which was machined to include a pre-crack notch. A dynamic load was induced on the bar with a shaker in order to force the crack to advance along the thickness of the substrate. The obtained raw data was processed and analyzed in the frequency domain and compared to the Lamb wave modes that were evaluated in previous Hsu-Nielsen testing for the substrate.
The influence of microstructure on tribological properties of WO3 thin films

Abstract The influence of the microstructure of WO 3 thin films upon friction and wear during sliding contact was studied using two different tribometers. The tungsten trioxide (WO 3 ) thin films of controlled microstructure were grown on R-plane sapphire substrates using electron cyclotron resonance (ECR) oxygen-plasma-assisted electron beam evaporation of WO 3 pellets. The WO 3 films were fabricated to consist of amorphous, polycrystalline or epitaxial microstructure, depending on the deposition temperature, as indicated by in situ RHEED analysis. Pin-on-disk testing of the WO 3 films was performed using 10 mm diameter sapphire and 440C stainless steel sliders and 1 N normal force. Epitaxial crystalline WO 3 films showed lowest friction ( μ ∼0.3 for both sapphire and steel spheres) and greatest production of debris, while amorphous WO 3 films exhibited higher friction coefficients (up to μ ∼0.6 for sapphire spheres and μ ∼1.1 for steel spheres), less debris production, and more slider wear. Epitaxial WO 3 films exhibited low friction ( μ ∼0.16) in single pass tests with sapphire and steel sliders (1 mm stroke, 0.1 mm/s, 0.1 N load,), whereas amorphous and polycrystalline WO 3 films showed transitions to much higher friction (up to μ ∼0.7). Lower friction and wear of WO 3 films with epitaxial structure compared to amorphous structure appears to be due to a lubricious WO 3 layer transferred to the slider from the epitaxial film.
Effect of Thermal Aging on the Interfacial Reactions of Tin-Based Solder Alloys and Copper Substrates and Kinetics of Formation and Growth of Intermetallic Compounds (Efeito do envelhecimento térmico nas reações interfaciais de ligas de soldagem branda a base de estanho em substratos de cobre e cinética de formação e crescimento de compostos intermetálicos)

The formation and growth of intermetallic compounds at the interface between four solder alloys, Sn-3.5Ag, Sn-0.7Cu, Sn-3.2Ag0.8Cu and Sn-9Zn, and Cu-plated substrates have been studied. Thermal aging tests for 20, 100, 200, 500 hours at 70, 100 and 150 oC were carried out. As expected, results indicate that the formation of the intermetallic layer is a diffusion-controlled process. Nevertheless, migration and dissolution of Cu into the solder was observed, especially at lower temperatures. The thickness of the layer of intermetallic compound increased with increasing aging temperature and time. The Sn-3.5Ag alloy showed the smallest intermetallic growth and the Sn-9Zn alloy the highest, compared to the other alloys. The results also show definite morphological differences between the Cu/Cu3Sn, the Cu3Sn/Cu6Sn5 and the Cu6Sn5/solder-matrix interfaces.
fMRI studies of associative encoding in young and elderly controls and mild Alzheimer’s disease

Objective: To examine alterations in patterns of brain activation seen in normal aging and in mild Alzheimer's disease by functional magnetic resonance imaging (fMRI) during an associative encoding task. Methods: 10 young controls, 10 elderly controls, and seven patients with mild Alzheimer's disease were studied using fMRI during a face–name association encoding task. The fMRI paradigm used a block design with three conditions: novel face–name pairs, repeated face–name pairs, and visual fixation. Results: The young and elderly controls differed primarily in the pattern of activation seen in prefrontal and parietal cortices: elderly controls showed significantly less activation in both superior and inferior prefrontal cortices but greater activation in parietal regions than younger controls during the encoding of novel face–name pairs. Compared with elderly controls, the Alzheimer patients showed significantly less activation in the hippocampal formation but greater activation in the medial parietal and posterior cingulate regions. Conclusions: The pattern of fMRI activation during the encoding of novel associations is differentially altered in the early stages of Alzheimer's disease compared with normal aging.
Cultivar identification of cherimoya (Annona cherimola Mill.) using isozyme markers

Abstract The cherimoya and its relatives are becoming increasingly important fruit crops in tropical and subtropical regions. However, virtually no reliable genetic markers have been developed for variety and species identification. Here we report isozyme variation patterns at 15 loci resolved from 8 enzyme systems for 15 varieties of cherimoya ( Annona cherimola ) and one variety of atemoya ( A. cherimola × A. squamosa ). We found sufficient isozyme variation to distinguish between all varieties analyzed, as well as clearly separating the atemoya from the cherimoyas. Using examples from our data, we demonstrate how isozyme markers can be used to solve problems of cherimoya cultivar identification and to determine the parentage of varieties.
Agricultural resource use in an andean coastal ecosystem

Five concurrent systems of agricultural resource management in the Viru Valley in Peru's arid northern coastal plain are discussed as adjustments to microenvironmental variations in soil humidity. Widespread dependence on canal irrigation in an environment characterized by uncertainty in the availability of river water affects the agrarian population in several ways. The upper socioeconomic class has adapted to uncertainty by implementing a deviation-counteracting mechanism (tubular wells) that provides water on demand, giving them flexibility in choice of agricultural activities. Another class of farmers is unable to introduce this mechanism, however, and consequently must depend on a repertoire of inflexible decisions to cope with uncertainty. Each group exploits different opportunity costs to increase economic gain. One pattern provides for expansion, whereas the other at best establishes stability and maintenance. Noncanal techniques permit expansion of cultivation in conditions where canal irrigation is not feasible, thereby improving the overall level of effectiveness of resource use. Alternative techniques do not involve regulatory mechanisms nor do they require complex, interlocking social, economic, and political components. Their presence and persistence in the agricultural system provide variation that may ultimately be amplified as the need to intensify resource exploitation increases in the future.
Pancreatic stenting prevents pancreatitis after biliary sphincterotomy in patients with sphincter of Oddi dysfunction

Abstract Background & Aims: Patients with sphincter of Oddi dysfunction are at high risk of developing pancreatitis after endoscopic biliary sphincterotomy. Impaired pancreatic drainage caused by pancreatic sphincter hypertension is the likely explanation for this increased risk. A prospective, randomized controlled trial was conducted to determine if ductal drainage with pancreatic stenting protects against pancreatitis after biliary sphincterotomy in patients with pancreatic sphincter hypertension. Methods: Eligible patients with pancreatic sphincter hypertension were randomized to groups with pancreatic duct stents (n = 41) or no stents (n = 39) after biliary sphincterotomy. The primary measured outcome was pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP). Results: Pancreatic stenting significantly decreased the risk of pancreatitis from 26% to 7% (10 of 39 in the no stent group and 3 of 41 in the stent group; P = 0.03). Only 1 patient in the stent group developed pancreatitis after sphincterotomy, and 2 others developed pancreatitis at the time of stent extraction. Patients in the no stent group were 10 times more likely to develop pancreatitis immediately after sphincterotomy than those in the stent group (relative risk, 10.5; 95% confidence interval, 1.4–78.3). Conclusions: Pancreatic duct stenting protects significantly against post-ERCP pancreatitis in patients with pancreatic sphincter hypertension undergoing biliary sphincterotomy. Stenting of the pancreatic duct should be strongly considered after biliary sphincterotomy for sphincter of Oddi dysfunction; pancreatic sphincter of Oddi manometry identifies which high-risk patients may benefit from pancreatic stenting. GASTROENTEROLOGY 1998;115:1518-1524
Effect of molecular weight on fibrous PVA produced by electrospinning

Abstract The effects of polymer weight average molecular weight (MW) on the fiber structure of electrospun polyvinylalcohol (PVA) have been studied. PVA with a degree of hydrolysis of 98–99% and with molecular weights ranging from 9000 to 186,000 g/mol was dissolved in water. The concentration (C) of the polymer in the solution was varied depending on the molecular weight. The solution was electrospun at 30 kV and the sample obtained on the collector was examined by scanning electron microscopy. It was observed that for each molecular weight, a fibrous structure was stabilized above a minimum concentration, generally corresponding to [η]C>5. The average fiber diameter was between 250 nm and 2 μm. The fiber diameter increases with MW and concentration. At low MW and/or concentrations ([η]C 9).
Perforated stomach following the Heimlich maneuver

The use of infradiaphragmatic abdominal pressure for relief of airway obstruction caused by food was first described by Henry Heimlich in 1974. Since that time, several complications have been reported. We report a case of gastric perforation occurring in a choking victim following the application of the Heimlich maneuver.
High thermal stability of carbon-coated L10-FePt nanoparticles prepared by salt-matrix annealing

Department of Physics, University of Texas at Arlington. Ames Laboratory and Department of Materials Science and Engineering, Iowa State University. NanoTech Institute, University of Texas at Dallas.