cssi/SciSciGPT-SciSciNet huggingface dataset:
Nifedipine in the Treatment of Cardiovascular Disease

Nifedipine, a calcium channel blocking agent, has been shown safe and effective in the treatment of various cardiac disorders. In Prinzmetal's variant angina, nifedipine relieves the acute spasm of a large coronary artery, and thereby reverses the sudden decrease in myocardial oxygen supply. In chronic stable angina, the efficacy of nifedipine stems from an interplay of direct and reflex effects. A decrease in systemic vascular resistance, and thus, myocardial oxygen demand, is considered the most important effect. Although this is partially offset by baroreceptor-mediated reflex increases in blood pressure and heart rate, the net effect is a decrease in myocardial oxygen consumption. The importance of nifedipine-induced increases in coronary blood flow in relieving stable angina remains controversial. Numerous clinical trials in patients with chronic angina have demonstrated that nifedipine increases exercise tolerance by lowering the heart rate-blood pressure product (an approximation of myocardial oxygen consumption). The maximal double product during exercise, however, does not increase, suggesting that the drug does not importantly improve myocardial oxygen supply. Nifedipine may also be of value in the therapy of unstable angina, acute myocardial infarction, and hypertension, as well as in the protection of the myocardium at risk during open heart surgery. However, definite recommendations on the use of the drug for these indications must await results of ongoing randomized studies. The effects of nifedipine are dose-related. Larger doses have been shown more effective than smaller doses, as long as an appropriate blood pressure is maintained. The side effects of nifedipine are mild and related to its vasodilating action.
Alterations of K-ras, p53, and erbB-2/neu in human lung adenocarcinomas.

The development of human adenocarcinoma of the lung involves multiple genetic changes including activation of oncogenes and loss of tumor suppressor genes. Patients whose lung tumors contain K- ras oncogene mutation, accumulation of the protein product of the tumor suppressor gene p53 , or erb B-2/ neu oncoprotein overexpression have been shown to have a worse prognosis. We examined these three genetic indicators in 29 lung adenocarcinomas to determine whether these markers are present in the same tumors or if they represent molecular changes that define different subsets of patients. P53 nuclear protein accumulation and erb B-2/ neu protein overexpression were determined by immunohistochemical analysis of cryostat sections of tumor specimens and corresponding normal lung tissue. K- ras mutations were detected by radiolabeled oligonucleotide probes, specific for the various twelfth codon mutations, hybridized to exon 1 of K- ras , which was amplified by the polymerase chain reaction. Increased nuclear accumulation of p53 protein was found in 11 adenocarcinomas (38 %). All of the p53 positive tumors were found to show high level staining and homogeneous expression of erb B-2/ neu protein. K- ras mutations were detected in seven tumors (24%), all of which overexpressed erb B-2/ neu . The presence of a K- ras mutation did not correlate with p53 accumulation. In total, 93% of the tumors were found to overexpress erb B-2/ neu , the highest being in one tumor with erb B-2/ neu gene amplification. The presence of K- ras twelfth codon mutation was associated with increased cigarette smoking. In conclusion, erb B-2/ neu overexpression is a common event in lung adenocarcinomas. Furthermore, the presence of K- ras mutation and p53 protein accumulation define separate groups of patients. The mechanisms by which these genetic alterations interact or adversely affect prognosis is unknown.
Krüppel-like Factors in Gastrointestinal Tract Development and Differentiation

A number of KLF family members are known to play important roles in the regulation of proliferation, differentiation, and development of the gastrointestinal tract. Of these, KLF4 (previously known as GKLF or EZF) and KLF5 (previously known as IKLF or BTEB2) have been the most extensively studied. In this chapter, we review the expression patterns and established functions for KLF family members in the gastrointestinal tract and offer insight into possible future areas of investigation of the KLFs in gastrointestinal differentiation and development.
Enanthems associated with uncommon viral syndromes.

Viral studies were done on 37 patients with enanthems and 17 well persons during the summer and fall of 1966; two-thirds of each group were 3 years old or less. Twenty-nine (84%) of the ill patients and 3 (18%) of the control patients had evidence of viral infection. Although all ill patients were referred to us because of an enanthem, it is significant that the oral signs were often only part of broader disease. The most common concurrent sign was exanthem, found in 17 of 37 ill patients. Six of 11 patients with Coxsackie A4 infection had rash which began with or after defervescence as red macules and papules on the face and trunk and lasted 1 to 4 days before disappearing or becoming vesicular. The vesicular lesions persisted 1 to 2 weeks. Exanthem was also present in Coxsackie B2 and A5-12 associated illnesses. Of 10 patients infected with Coxsackie A 16 virus, 6 had significant submandibular adenopathy, and 2 of 5 with exanthem had urticaria. In several ill patients laboratory findings were unexpected in view of clinical diagnoses. This was particularly true with herpetic stomatitis and incomplete hand, foot, and mouth syndrome.
The Coulomb gap: A review, and new developments

Abstract A survey is presented of experimental and theoretical work on the problem of Coulomb interactions in a Mott-Anderson insulator, since its inception, but emphasizing recent developments. The paper also attempts to explain the basic physical considerations, to point out some existing disagreements and to assess to what degree these may have been resolved by recent work.
Quantitative analysis of manganese, chromium and molybdenum by ion-pair reversed-phase high-performance liquid chromatography with pre-column derivatization and UV-visible detection

Abstract An ion-pair reversed-phase high-performance liquid chromatographic method with UV–visible spectrophotometric detection is proposed for the simultaneous determination of manganese, chromium and molybdenum. By using a C18-bonded silica column, 4-(2-pyridylazo)resorcinol (PAR) chelates of Mn(II), Cr(VI) and Mo(VI) were successfully separated and accurately determined at 480 nm. Tetrabutylammonium bromide (TBAB) was used as the ion-pair reagent. Effects of pH, the buffer system, the concentration of buffer, the color developing time, the concentration of chelating reagent and the ion-pair reagent on the resolution were investigated. PAR chelates were eluted within 20 min at a flow-rate of 1.0 ml min−1 with a methanol aqueous mobile phase, CH3OH–water (20:80, v/v), containing 1.0·10−3 mol l−1 acetate buffer (pH 6.5), 1.8·10−2 mol l−1 TBAB and 2.0·10−4 mol l−1 PAR. The feasibility of the proposed method was verified with the standard reference materials of nickel-based alloys. The nickel-based alloys were analyzed chromatographically after ammonium pretreatment. Under the optimum conditions, the detection limits for the chelates of Mn(II), Cr(VI) and Mo(VI) were 0.31, 4.2 and 4.6 ng with 100 μl injection, respectively. The accuracy of the proposed chromatographic method was verified by good agreement between the values obtained by this method and certified values.
Gestational nicotine treatment modulates cell death/survival-related pathways in the brains of adolescent female rats

Gestational exposure to nicotine affects brain development, leading to numerous behavioural and physiological deficits in the offspring during adolescence. To analyse the molecular mechanisms underlying these effects, a pathway-focused oligonucleotide microarray was used to determine gene expression profiles in five brain regions (i.e. amygdala, prefrontal cortex, nucleus accumbens, periventricular nucleus of the hypothalamus, and caudate putamen CPu) of adolescent rats that received nicotine or saline during gestation. Following appropriate statistical and Gene Set Enrichment Analyses, 24 cell death/survival-related pathways were found to be significantly modulated by gestational nicotine. On the basis of their biological functions, these pathways can be classified into three categories: growth factor, death receptor, and kinase cascade. We employed a quantitative real-time PCR array to verify the findings by measuring the expression of 29 genes involved in cell death/survival-related pathways. Together, our findings indicate that gestational nicotine exposure has significant effects on gene expression in cell death/survival-related pathways in the brains of adolescent offspring. Such effects appear to be brain region-specific and are realized through regulation of the expression of growth factors and receptors, caspases, kinases, and transcription factors. On the basis of these findings, we offer a hypothetical model to explain how gestational nicotine exposure may affect cell death and survival in the brains of adolescent offspring by regulating the balance between growth-factor and death-receptor pathways.
Rye as a Feed for Poultry

Abstract THERE is a considerable area of sandy soil in Wisconsin and several sections in other states where rye can be grown to advantage. In those sections where rye is produced extensively, soil conditions are usually favorable for poultry production. Rye has never been favorably known as a poultry feed. Whenever the price of rye is low it would be desirable, in those sections where rye is the main grain crop, to feed a part of the crop to the poultry flocks. Many farmers report that rye is not palatable. Experience shows that if rye is finely ground it has a tendency to be “sticky.” Halpin and Holmes (1932) in an attempt to learn ways of incorporating rye in the chick ration report that the droppings of the rye-fed chicks contained a pasty material which clung to the toes of the chicks. Large round balls adhered to each toe. The average . . .
An in situ cross-linking hybrid hydrogel for controlled release of proteins

There is a clear need for methods to provide a safe controlled release of therapeutic proteins, either to achieve and maintain high local protein concentrations, or for sustained systemic delivery. We have developed a protein delivery system that combines in situ cross-linkable polysaccharide hydrogels with gelatin. This formulation is injectable, easy to apply, and obviates the need for organic solvents or potentially toxic cross-linking agents in the formulation process. The cross-linked polysaccharides themselves (comprising hyaluronic acid, dextran and/or carboxymethylcellulose) provided prolonged release of fluorescently labeled albumin (FITC-albumin). The duration of release was markedly extended by the incorporation of gelatin into the formulation: FITC-albumin and interleukin-2 (IL-2) were released over the course of more than 3 weeks. The IL-2 maintained >70% activity throughout that time. Gelatin also accelerated the gelation time of the hydrogels, and reduced their swelling in phosphate-buffered saline. The composite hydrogel (dextran-carboxymethylcellulose-gelatin) showed minimal cytotoxicity in vitro, and benign tissue reaction after subcutaneous injection in rats.
The tubulin-bound conformation of paclitaxel: T-taxol vs "PTX-NY".

Nearly 35 years after its discovery and 11 years after FDA approval of paclitaxel (PTX) as a breakthrough anticancer drug, the 3-D structure of the agent bound to its β-tubulin target was proposed to be T-Taxol. The latter bioactive form has recently been challenged by the Ojima group with a structure, “PTX-NY” (“REDOR Taxol”), in which the C-13 side chain is proposed to adopt a different conformation and an alternative hydrogen-bonding pattern in the tubulin binding site. Previously, the two conformers were compared to show that only T-Taxol fits the PTX-derived electron crystallographic density. That work has been extended by molecular mechanics and quantum chemical methods to reveal that the PTX-NY conformation is relatively less stable, on average, by 10−11 kcal/mol. In agreement with NMR studies, an 11 ns molecular dynamics treatment for PTX in an explicit water pool locates T-Taxol along the trajectory, but not PTX-NY. Docking of various PTX conformers into the electron crystallographic binding site...
Alphaherpesvirus antigen quantitation to optimize the diagnosis of herpes B virus infection

Standardized, quantified virus antigen stocks are essential for dependable quality control of diagnostic assays. Five simple, rapid and economical direct enzyme linked immunoassays (dELISA) were developed to standardize and optimize antigen from five major cross-reacting alphaherpesviruses: herpes B virus, herpesvirus papio 2, langur monkey herpesvirus, herpes simplex virus-1 and herpes simplex virus-2. Each dELISA relied on pools of convalescent sera from rhesus monkeys, baboons, langurs and humans. Conjugates were prepared from purified IgG preparations, fractionated from the same sera and then labeled with peroxidase. Serum coated microplates could be stored at -70 degrees C for at least 1 year before use. The duration of the test was approximately 2.5 h if plates were prepared at an earlier time. Virus antigen titers could be determined from titration curves or from single dilutions using a standard curve. The sensitivity of detection was approximately 8x10(5) PFU/ml. This sensitivity sufficed for the determination of viral antigen mass in live or detergent treated virus stocks that usually contain at least 1x10(8) PFU/ml. The assays were valuable for quality assurance of diagnostic serological assays for herpes B virus and other alphaherpesviruses.
High-Performance Workplace Practices in Nursing Homes: An Economic Perspective

To develop implications for research, practice and policy, selected economics and human resources management research literature was reviewed to compare and contrast nursing home culture change work practices with high-performance human resource management systems in other industries. The organization of nursing home work under culture change has much in common with high-performance work systems, which are characterized by increased autonomy for front-line workers, self-managed teams, flattened supervisory hierarchy, and the aspiration that workers use specific knowledge gained on the job to enhance quality and customization. However, successful high-performance work systems also entail intensive recruitment, screening, and on-going training of workers, and compensation that supports selective hiring and worker commitment; these features are not usual in the nursing home sector. Thus despite many parallels with high-performance work systems, culture change work systems are missing essential elements: those that require higher compensation. If purchasers, including public payers, were willing to pay for customized, resident-centered care, productivity gains could be shared with workers, and the nursing home sector could move from a low-road to a high-road employment system.
Techniques for pelvic ring reduction

Abstract This review describes surgical techniques used to treat some common pelvic ring disruptions including the indications for fixation, as well as operative techniques. Fracture patterns discussed include symphaseal injuries, sacral-iliac joint fractures and dislocations, crescent fractures, sacral fractures, and fractures involving the iliac wing. Additionally, postoperative management and complications are reviewed.
A cis-acting element within the hepatitis A virus 5'-non-coding region required for in vitro translation

Abstract Every picornavirus studied thus far has a sequence within the 5'-non-coding region that is required for internal ribosome binding and translation of the polyprotein. In an attempt to identify this region in hepatitis A virus we constructed a truncated hepatitis A virus (HAV) cDNA clone that contains the entire 736 bp 5' non-coding region (5'-NCR) and 754 base pairs of the viral capsid coding region (P1) under control of the SP6 promoter. In vitro transcription and translation of this transcript in a rabbit reticulocyte lysate yielded a protein product of about 29 kDa as analyzed by autoradiography following sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS..PAGE). A series of mutations of this construct have defined a minimal sequence between bases 347 and 734 in the 5'-NCR that is required for efficient in vitro translation. The deleted constructs (D 523–734 and D 632–734) showed a reduced ability to translate in the rabbit reticulocyte lysate system in comparison with the full-length 5'-NCR construct, pH1489. The translation of these deleted constructs was artificially restored by the addition of a 5'-terminal methylated cap structure, m7GpppG, to the RNA. This increase in translational efficiency could be competed away with cap analog (m7GDP) thus indicating that this region is required for cap-independent internal ribosome binding for HAV translation.
Electrostatic cylindrical mirror spectrometer for conversion electron Mössbauer spectroscopy

Abstract An electrostatic cylindrical mirror analyzer for intermediate energy internal conversion electrons has been constructed. The apparatus is especially designed to work with the electrons emitted in the 14.4 keV transition of 57Fe, and it is able to measure simultaneously electrons originating at three different atomic shells. With computed resolution in energy of 0.47% (fwhm), the solid angle is 2.83% of 4π, the transmission 70% and the maximum electron source diameter 2 mm. Experimental results with different electron sources are presented.
Isolation of the vma-6 gene encoding a 41 kDa subunit of the Neurospora crassa vacuolar ATPase, and an adjoining gene encoding a ribosome-associated protein.

Abstract The vma-6 gene, encoding a membrane-associated subunit of the vacuolar H+-ATPase from Neurospora crassa, was cloned and sequenced. The gene contains three small introns and encodes a protein of 41 005 Da. When compared with homologous polypeptides from other species, the N. crassa protein contains a unique glycine-rich region. Three conserved cysteine residues, previously unrecognized, have been identified. An unrelated gene encoding a protein of 31 701 Da was found 2.1 kb downstream of vma-6. The second gene appears to encode the N. crassa homolog of a ribosome-associated protein identified previously in several plant and mammalian cells, and was named rap-1.
Bronchial thermoplasty for asthma : A critical review of a new therapy

Bronchial thermoplasty (BT) is a novel experimental procedure involving the application of controlled heat from a radiofrequency source to the airway wall as a means to reduce airway smooth muscle in the airway wall. After BT was shown to reduce airway smooth muscle in preclinical studies in dogs, clinical studies in humans revealed that BT resulted in a significant improvement in asthma outcomes including mild asthma exacerbations, asthma symptom-free days, asthma rescue medication use, and airway hyperresponsiveness as measured by methacholine PC(20). A second trial in humans revealed that BT was safe and effective in patients with severe asthma refractory to the current standard of care. While current trials are ongoing, BT holds promise as an exciting novel therapy in the management of patients with asthma.
The Failure and Promise of Mandated Consumer Mortgage Disclosures: Evidence from Qualitative Interviews and a Controlled Experiment with Mortgage Borrowers

Policy responses to record rates of mortgage delinquency, default, and foreclosure will likely affect the cost and availability of consumer credit for decades to come. Although the current crisis began over two years ago, one consumer policy change that surely passes a cost-benefit test has yet to be adopted. Consumers still do not receive one clear disclosure document that conveys the key costs and risks of their mortgages. The results of this study, based on quantitative testing in a controlled, randomized experiment with more than 800 mortgage borrowers, and in-depth, qualitative interviews with several dozen additional borrowers, suggests that federally mandated consumer mortgage disclosures failed, resulting in many borrowers who did not understand the costs and risks of their loans, likely contributing to the mortgage crisis. An overhaul of consumer mortgage disclosures, culminating in a single disclosure document, designed using a combination of qualitative and quantitative consumer research, could substantially improve consumer understanding of their mortgage choices. The failure of mandated disclosures to convey mortgage terms to borrowers was not due to cognitive limitations or irrationality of consumers, nor to an irreducible complexity of new mortgage instruments, but to poorly designed disclosures. Disclosure documents failed to include key loan information, and the information disclosed was often confusing and sometimes misleading. Problems with mandated disclosures were evident across a range of consumers and loan types. Prime and subprime borrowers were similarly confused. Confusion The Failure and Promise of Mandated Consumer Mortgage Disclosures: Evidence from Qualitative Interviews and a Controlled Experiment with Mortgage Borrowers
Cesium chloride density-gradient studies of nuclear proteins. Studies with control and irradiated nuclei.

Abstract Nucleoprotein gels were fractionated on a CsCl density gradient. The major component separated was found in a peak of density 1.66 g/cm 3 , consisting of nearly all the DNA and part of the histone originally present in the nucleus. The remainder of the histones was found in a layer floating on the surface of the CsCl. The residual or acid-insoluble protein was found in a peak of density 1.48 g/cm 3 ; possibly due to reaction with CsCl this fraction exhibited some unusual properties, notably an ultraviolet absorption maximum of 320 mμ. Nucleoprotein and purified DNA added separately to the gradient were located in the same peak after centrifugation. Homogenization of nucleoprotein before centrifugation apparently separated most of the DNA from the protein. Some conclusions about the arrangement of DNA and protein in the chromosome are drawn from these findings. Doses of irradiation up to 10 6 rad given to rat-liver nuclei in vitro do not produce any major changes in the buoyant density of the main nucleoprotein component. Doses as low as 100 rad result in the appearance of a second peak on the density gradient of buoyant density 1.75 g/cm 3 , containing DNA and material with an absorption maximum at 320 mμ. It seems likely that the material in this peak is a radiation-induced complex of DNA and the low-density 320 mμ-absorbing material observed in control nuclei.
Use of positively charged, leaving groups in the synthesis of α-D-linked galactosides. Attempted synthesis of 3-O-α-(D-(galactopyranosyl)-D-galactose

Abstract Quaternary ammonium and phosphonium salts were readily obtained by treating 2,3,4,6-tetra-O-benzyl-α- D -galactopyranosyl bromide with tertiary amines and phosphines in various solvents under anhydrous conditions. Optical rotations and n.m.r. spectra of the hygroscopic syrups indicated that they exist mainly in the β- D configuration. Several dialkyl sulfides reacted very slowly with the galactosyl bromide and no conclusive evidence for sulfonium salt formation was obtained. 2,3,4,6-Tetra-O-benzyl-α- D -galactopyranosyl chloride failed to react with any of the nucleophiles. Methanolysis reactions of the phosphonium salts were too slow to be practical and were not studied extensively. Methanolyses of several quaternary ammonium salts in various solvents were not completely stereospecific, but gave good yields of methyl 2,3,4,6-tetra-O-benzyl-α- D -galactopyranoside. Attempted reactions of benzyl 2-O-benzoyl-4,6-O-benzylidene-β- D -galactopyranoside with quaternary ammonium salts derived from 2,3,4,6-tetra-O-benzyl-α- D -galactopyranosyl bromide failed to produce the corresponding derivative of 3-O-(α- D -galactopyranosyl)- D -galactose.
Self-sacrificial behavior in crisis situations: The competing roles of behavioral and situational factors

As charismatic and transformational leadership theories have broadened their perspective to include situational factors (i.e., crisis), it is important to understand how specific leader behaviors might interact with such situations. Recently, Choi and Mai-Dalton [Leadersh. Q. 10 (1999) 397; Leadersh. Q. 9 (1998) 475] have given both empirical and theoretical attention to the behavior of self-sacrifice, which is an important facet of both Transformational [Organ. Dyn. 13 (1985) 26] and Charismatic Leadership Theories [Acad. Manage. Rev. 12 (1987) 637; House, R. J. (1977). A 1976 theory of charismatic leadership. In J. G. Hunt & L. L. Larson (Eds.), Leadership: The cutting edge (pp. 189–207). Carbondale: Southern Illinois University Press]. The present experimental study investigates the effects of self-sacrificial behavior, along with the effects of situational crisis on followers' perceptions of their leader's charisma and organizational commitment. Leaders are perceived particularly well when exhibiting self-sacrificial behavior in times of crisis.
The cost-effectiveness of bariatric surgery: Craig BM, Tseng DS. Cost-Effectiveness of Gastric Bypass for Severe Obesity, Am J Intern Med 2002;113:491–8

The purpose of the study was to estimate the cost-effectiveness of gastric bypass in the treatment of severe obesity (body mass index > 40). A deterministic decision analysis that compared the lifetime expected costs and outcomes between open gastric bypass and no treatment of severe obesity from the payer perspective was performed. Men and women between the ages of 35 and 55 yr, with body mass index between 40 and 50 kg/m2, who did not have cardiac disease and who failed conservative treatment, including pharmacotherapy, were included. Cost-effectiveness ratio of the base case conditions was made with parameter estimates from the literature and expert discussion and expressed as cost per quality-adjusted life-years (QALY). One- and two-way sensitivity analyses were performed on selected variables. Gastric bypass was not cost-saving, because the reduction in lifetime medical costs was less than the cost of treatment in any subgroup. The base case cost-effectiveness ratios ranged from $5,400 to $16,100 for women and from $10,700 to $35,600 per QALY for men. Sensitivity analysis demonstrated that in older, less obese men, the cost effectiveness ratio was responsive to the amount of weight lost, obesity-related quality of life, and complication rates. Parameter variation did not significantly affect cost-effectiveness ratios in the remaining patients. The authors concluded that gastric bypass is a cost-effective alternative to no treatment in the severely obese, at less than $50,000 per QALY.
Distribution of software engineering concepts beyond the software engineering course

The importance of the role of documentation in the development and maintenance of software is not in dispute among computer professionals. Within the profession, software has come to mean more than just the source or object code which is produced. A modern definition of software includes documents as a vital component. The largest part of such documentation is external to the program and records the history of the project. Included could be project plans, requirements specification, preliminary detailed code design, user-directed manuals and maintenance journals.All too often the computer science curriculum, whether by design or default, limits student experience with external documentation to specialized courses such as software engineering. While the documentation experience provided by these courses may prove valuable, its quality may be limited by the student's attitude. If the student's previous experience has been limited to internal documentation, there is a good chance that he has come to view documentation as an add-on, something to be completed after the project is really finished. It is difficult to alter this mind-set.Identification of a solution to this problem may require not only a reevaluation of the documentation requirements for student software projects but an examination of the availability of programming languages and design tools which support the documentation effort. This paper reports the development of several design tools which are intended for student use in the preparation of preliminary project documentation. Special among these is an interactive graphics editor to be used to assist in the design, documentation and implementation of programs.
A new filtering method for linear singularly perturbed systems

In this paper we present a new method which allows complete decomposition of the optimal global Kalman filter for linear singularly perturbed systems into pure-slow and pure-fast local optimal filters both driven by the system measurements. The method is based on the exact decomposition of the global singularly perturbed algebraic Riccati equation into pure-slow and pure-fast local algebraic Riccati equations. An F-8 aircraft example demonstrates the proposed method. >
Insights from biophysical studies on the role of polyunsaturated fatty acids for function of G-protein coupled membrane receptors

The composition of the lipid matrix is critical for function of membrane proteins. Perhaps one of the best studied examples is the function of the G-protein-coupled membrane receptor (GPCR) rhodopsin which is located in membranes with high content of phospholipids with polyunsaturated docosahexaenoic acid chains (DHA, 22:6n-3). Technological advances enabled a more detailed study of structure and dynamics of DHA chains and their interaction with rhodopsin. It was established that polyunsaturated DHA differs from saturated and monounsaturated hydrocarbon chains by far more rapid structural conversions. Furthermore, DHA chains tend to have higher density near the lipid/water interface while density of saturated chains is higher in the bilayer center. The interface of rhodopsin has a small number of sites for tighter interaction with DHA. Polyunsaturated phosphatidylethanolamines accumulate preferentially near the protein. Surprisingly, the high conformational freedom of most DHA chains is not measurably reduced upon interaction with rhodopsin. While some observations point at an involvement of continuum elastic properties of membranes in modulation of rhodopsin function, there is growing evidence for a role of weakly specific DHA–rhodopsin interactions.
High-speed beams of small particles

Abstract Beams of latex particles with diameters of 0.126, 0.365, and 1.305 μ were generated by continuously expanding an aerosol through a nozzle into an evacuated chamber and extracting the core of the jet with a skimmer. A convergent nozzle with a throat diameter of 157 μ and capillaries of different lengths but the same inner diameter were used. The expansion angle, the intensity, and the velocity of the beam were investigated as functions of the source pressure, the particle size, and the nozzle geometry. Without collimation, minimum expansion angles of about 10 −4 sr. and particle velocities of 200 m./sec. have been achieved. The possibility of aerodynamically focusing particles of a narrow size range is suggested by the experimental results.
Visual memories and mental images

A model is presented for the architecture of the neural networks which encode visual information for storage and which reconstruct iconic representations from storage representations. (Iconic representations are geometrically similar to projections of the objects they represent.) Each storage representation consists of a sequence of patterns derived while the eyes fixate at different positions in the visual field. Each pattern in the sequence has three components: (1) a control component which describes both where the eyes fixated and the size of the attended scene fragment; (2) a surface quality component which describes visual surface characteristics of the object; and (3) a spatial component which describes the spatial extent, spatial position (depth), surface orientation and visual flow (movement) of the surface having the specified surface characteristics. Prior to storage, all spatial components are transformed using a complex logarithmic mapping. As a consequence, stored spatial patterns are not iconic representations of the scene fragments they represent. Also, storage representations can be recognized and reconstructed at any desired size and orientation: they are size and orientation invariant. During reconstruction, each pattern in the storage representation is transformed back into an iconic representation using a complex exponential mapping. One consequence of the combined complex logarithmic and exponential mappings and the limited size of the storage representations is that the fidelity of the recalled information degrades exponentially from its centre. A neural network, called spatial memory, not only holds the partially reconstructed representation during recall, but also shifts it to remain in registration with the fragment currently being recalled and combined. The control system uses the control component of each stored pattern and knowledge of the size and orientation of the reconstruction to determine how to shift the partially reconstructed representation in spatial memory. Due to the decreasing fidelity from the centre to the perimeter of each reconstructed scene fragment, spatial memory only preserves information from overlapping fragments having the highest fidelity. It does so by maintaining and using fidelity information for each position in the reconstructed representation. Spatial memory can maintain a current stable representation of the visual world. It can also magnify, reduce, shift and rotate representations. The representations are therefore independent of their position in spatial memory. It is suggested that the representations held and processed by spatial memory correspond to the representations we call mental images and for this reason they are called mental images in the model.
Singularities of n-dimensional cell functions and the associated index theory

Abstract In [1,2] a new and promising method for global analysis of non-linear systems has been presented in the form of cell-to-cell mappings. It is seen to be a very powerful method indeed. However, many fundamental questions about this new kind of mapping remain to be investigated. In this paper we present a theory of singularities for cell functions by introducing a system of singular entities. The key steps in the development are to introduce a simplicial structure to the cell space and to use simplicial mappings to create an associated continuous vector field for a given cell function. The construction of the associated vector field also allows us to develop a theory of index for cell functions. This theory of index then serves very nicely as a unifying force for the whole development reported in this paper.
Effect of viscosity and iodine concentration of nonionic radiographic contrast media on coronary arteriography in patients

To assess the influence of viscosity and iodine concentration, three matched and standardized left coronary arteriograms were obtained in 20 patients using iopamidol (Isovue-370), ioversol (Optiray-320), and iohexol (Omnipaque-350). The order of contrast media was randomized and the administration of contrast was double-blinded. Quantitative densitometric angiographic evaluation of the coronary angiograms was performed in addition to independent operator qualitative assessment. The injection volume of iopamidol (5.4 +/- 1.0 ml) was slightly but significantly less than that of ioversol and iohexol (5.6 +/- 1.0 ml, 5.7 +/- 1.0 ml, both p less than 0.05). The calculated iodine concentration was also lower for ioversol (1.7 +/- 0.32 gm) than for iopamidol (1.98 +/- 0.35 gm) and iohexhol (1.9 +/- 0.35 gm, both p less than 0.05). There were significantly lower contrast syringe injection pressures for ioversol (6.6 +/- 0.8 atm) than for iopamidol (7.5 +/- 0.9 atm) and iohexol (7.2 +/- 1.1 atm, both p less than 0.05). The quantitative densitometric analysis failed to demonstrate significant differences among the contrast media with respect to image density parameters for any individual agent. All coronary angiograms were deemed of diagnostic quality. The data in this study indicated that although differences in iodine concentration exist among the three agents, operator compensation with more rapid contrast delivery (higher volume) and lower viscosity (lower injection pressure) produced equivalent image opacification during coronary angiography. Given the same incidence of adverse hemodynamic and clinical effects, selection of a low viscosity media theoretically provides an advantage during procedures using small diameter catheters or interventional procedures requiring contrast visualization through reduced catheter lumina.
"Ethics and clinical research" revisited. A tribute to Henry K. Beecher

The doctrine of informed consent, borrowed from the law of torts, cannot be readily transplanted into therapeutic settings. The broader, as yet unrealized, idea of informed consent, which suggests that parties must make decisions jointly, should guide interactions between physicians and patients or investigators and subjects.
Coordinated movement and rapport in teacher-student interactions

High school students in 19 teaching dyads were measured for their degree of interpersonal coordination and rapport. Two types of movement coordination were identified and rated by a group of untrained judges: the degree of perceivedmovement synchrony, and the extent ofbehavior matching. Ratings of movement synchrony in true interactions were significantly greater than similar ratings in pseudo interaction control clips (i.e., video clips that appeared to be of the teacher and student interacting but were, in fact, a combination of video clips of each interactant recorded fromdifferent points within their interaction). Self-ratings collected from interactants indicated a strong relationship between participants' rapport and the degree of movement synchrony perceived by raters. This relationship remained even after observer ratings of each interactant's friendliness, a possible confound, were partialled out. This result provided empirical evidence for the hypothesized relationship between rapport and interpersonal coordination (Tickle-Degnen & Rosenthal, 1987). Ratings of behavior matching did not differ significantly between the true interactions and pseudo interaction control clips. Behavior matching failed to correlate significantly with dyadic rapport. It was, however, significantly predictive of self-reported anxiety.
Single molecule probes of membrane structure: Orientation of BODIPY probes in DPPC as a function of probe structure

Single molecule fluorescence measurements have recently been used to probe the orientation of fluorescent lipid analogs doped into lipid films at trace levels. Using defocused polarized total internal reflection fluorescence microscopy (PTIRF-M), these studies have shown that fluorophore orientation responds to changes in membrane surface pressure and composition, providing a molecular level marker of membrane structure. Here we extend those studies by characterizing the single molecule orientations of six related BODIPY probes doped into monolayers of DPPC. Langmuir–Blodgett monolayers transferred at various surface pressures are used to compare the response from fluorescent lipid analogs in which the location of the BODIPY probe is varied along the length of the acyl chain. For each BODIPY probe location along the chain, comparisons are made between analogs containing phosphocholine and smaller fatty acid headgroups. Together these studies show a general propensity of the BODIPY analogs to insert into membranes with the BODIPY probe aligned along the acyl chains or looped back to interact with the headgroups. For all BODIPY probes studied, a bimodal orientation distribution is observed which is sensitive to surface pressure, with the population of BODIPY probes aligned along the acyl chains increasing with elevated surface pressure. Trends in the single molecule orientations for the six analogs reveal a configuration where optimal placement of the BODIPY probe within the acyl chain maximizes its sensitivity to the surrounding membrane structure. These results are discussed in terms of balancing the effects of headgroup association with acyl chain length in designing the optimal placement of the BODIPY probe.
Fatigue Life Estimation in Notched Geometries

The fatigue failure in components is divided in two stages: an initiation stage that defines the number of cycles that it takes for a crack to appear in the material and a second stage that estimates the number of cycles where the crack grows until it becomes unstable.Usual fatigue life estimation procedures (in crack free components) only consider the initiation stage and assume that the crack propagation period is relatively small compared with the total life. However, in the case of severely notched geometries like threaded connections, the propagation stage can be an important part of the component fatigue life and must be evaluated.A fundamental issue in the calculation of initiation plus propagation fatigue life is the definition of the initial crack size after the initiation stage. In the present study techniques for crack initiation and crack growth are described. Also the procedure to combine the two techniques and define an initial crack size is presented. The study is based on previous work of C. Navarro, et al. [1]. Additionally, validation against experimental tests on notched specimens is provided.Copyright © 2013 by ASME
Regional myocardial blood flow and glucose utilization in symptomatic patients with hypertrophic cardiomyopathy.

BACKGROUNDPrevious studies suggested the presence of myocardial ischemia in symptomatic patients with hypertrophic cardiomyopathy. Positron emission tomography, a technique that can identify metabolic consequences of ischemia in coronary artery disease, permits the noninvasive measurements of regional myocardial blood flow and glucose metabolism. This new quantitative imaging approach should therefore be suitable for detecting a possible enhancement of glucose utilization in myocardium of patients with hypertrophic cardiomyopathy and thus may help to elucidate the pathomechanism of ischemia in this disease.METHODS AND RESULTSIn 13 symptomatic patients with hypertrophic cardiomyopathy, myocardial blood flow and glucose utilization were measured with intravenous N-13-ammonia and F-18 deoxyglucose at rest and, in four patients, again during supine bicycle exercise. At rest, blood flow was significantly lower in hypertrophied than in normal myocardium (0.78 +/- 0.19 versus 0.99 +/- 0.13 mL.min-1.g-1, p < 0.02...
Thermal characterization of embedded electronic features by an integrated system of CCD thermography and self-adaptive numerical modeling

This work provides a practical application of a coupled experimental-computational system devised for the full characterization of the thermal behavior of complex three-dimensional active submicron electronic devices. A thermoreflectance thermography (TRTG) technique is used to non-invasively measure the 2D surface temperature field of an activated device, with submicron spatial resolution. The measured planar temperature distribution field is then used as input for an ultra-fast inverse computational solution to derive the three-dimensional temperature distribution throughout the device. For the purposes of this investigation, test micro-heater devices were constructed on epitaxial layers of natural (Si) and isotopically pure (Si^2^8) silicon. Then, all devices were activated and measured with the TRTG technique. In order to demonstrate the coupled experimental-computational system, the measured temperature fields of the samples whose thermal properties are known (Si) were used to extract critical physical parameters (the oxide layer thickness and the effective heater length). Then, since the devices with unknown thermal properties (Si^2^8) share the same construction with the Si devices, the extracted parameters were used together with the measured planar temperature fields to derive the thermal conductivity of Si^2^8. The extracted oxide layer thickness and thermal conductivity of Si^2^8 compared very closely to values obtained by other independent direct methods.
Operational experience with a 2.5 × 1.5 meter delay line chamber

Abstract We have completed a fixed target hadron experiment at Fermilab which used a large delay line drift chamber in the tracking spectrometer. Such a chamber delivers a 2-dimensional coordinate for each hit, uses conventional TDCs, and requires no special low noise electronics. The chamber's performance was quite satisfactory, but some improvement might be realized with better construction and operating procedures.
A survey of computer-assisted research in modern German

This survey is limited to computer-aided research on German language and literature of the seventeenth through twentieth century.' Readers interested in other Germanic languages should begin by consulting Arne Zettersten's article on current computer-aided research in Scandinavia [1976: 275-80] 2 and recent issues of Informatie Nederlandse Lexicologie for information on Dutch projects.3 Those interested in early German before 1600 should consult Rudolf Hirschmann's informative survey of this period [1974: 279-84]. Also excluded from consideration are machine translation and computer-aided instruction, each of which merits a separate discussion. Rather than attempting to cover all computeraided projects in modern German undertaken during the last decade, I shall concentrate on a few centers of activity, projects, conferences and publications which characterize the most significant and frequently pursued areas of research. An introductory survey of German texts in machine-readable form is followed by a discussion of word-indexes and standard concordances produced since the midsixties. Discussion then proceeds to other types of computer-generated indexes and lexica, to statistical studies of the phonological, syntactic and semantic structure of German texts, and finally to some important conferences, journals and anthologies devoted in whole or in part to German literary and linguistic data processing.
Cleavage sites in the polypeptide precursors of poliovirus protein P2-X

Abstract Partial amino-terminal sequence analysis has been performed on the three major polypeptide products (P2-3b, P2-5b, and P2-X) from the central region (P2) of the poliovirus polyprotein, and this analysis precisely locates the amino termini of these products with respect to the nucleotide sequence of the poliovirus RNA genome. Like most of the products of the replicase region (P3), the amino termini of P2-5b and P2-X are generated by cleavage between glutamine and glycine residues. Thus, P2-5b and P2-X are probably both produced by the action of a single (virus-encoded?) proteinase. The amino terminus of P2-3b, on the other hand, is produced by a cleavage between the carboxy-terminal tyrosine of VP1 and the glycine encoded by nucleotides 3381–3383. This result may suggest that more than one proteolytic activity is required for the complete processing of the poliovirus polyprotein.