cssi/SciSciGPT-SciSciNet huggingface dataset:
Toward Nonoxidative Routes to Oxygenated Organics: Stereospecific Deoxydehydration of Diols and Polyols to Alkenes and Allylic Alcohols Catalyzed by the Metal Oxo Complex (C5Me5)ReO3

Carbohydrates, with one oxygen atom per carbon, are actually too oxygen-rich relative to many important oxygenated organics. Removal of carbohydrate hydroxyl groups would therefore be useful, particularly if a different reactive functional group could be introduced. This has now been accomplished via a new catalytic reaction, the stereospecific deoxydehydration of diols and polyols to alkenes and allylic alcohols. In summary, the present catalytic method for net didehydroxylation of diols is potentially competitive in many cases with the standard Corey-Winter approach, treatment of the diol thionocarbonate with phosphite reagents at elevated temperatures. Other metal diolate complexes are known to extrude alkene at room temperature. Hence we believe that it should be possible to develop related catalytic cycles for net diol didehydroxylation that function under milder conditions, comparable to the best current stoichiometric methods. Finally, catalytic cycles utilizing more inexpensive, environmentally friendly reductants, such as hydrogen or carbon monoxide, would facilitate bulk carbohydrate deoxydehydration reactions to produce desirable oxygenated organics. 24 refs., 1 fig.
Modeling high-frequency acoustic backscattering from gas voids buried in sediments

It was found in a previous paper that strong acoustic backscattering from a soft sediment in Eckernforde Bay, Germany, is caused by scatterers buried beneath the sea floor. The scatterers are methane gas voids of nonspherical shape. This paper models backscattering due to such gas voids. Scattering cross sections of oblate spheroids are calculated to approximate those of gas voids. Proper statistical averages are taken to make model/data comparisons. It is found that this single scattering model compares favorably with measured acoustic backscattering data at 40 kHz. In the model, density and spatial distribution of gas voids are derived from limited core data.
The Bournemouth Affair: Britain's First Primary Election

T HIS PAPER EXAMINES THE RELATIONS between a Member of Parliament, his constituents, and his leaders under conditions of considerable stress. Recent interpretations of the British party system have tended to emphasize the centralization of power in both major parties as a result of the constitutional principle that governments be responsible to Parliament and to the whole electorate and of the need to appeal to a wider range of views than those embodied in the formal membership of a single party, if the party in question is to enjoy success at the polls.' These interpretations, which appear to be generally well-founded, have entailed minimizing the importance both of the backbencher and the local party organizations. Only a few polemical journalists have suggested that the ordinary Member or constituency party has ceased to be a real influence in British politics, but, in large part because of the attention devoted -to the leaders, few areas of British politics remain in more obscurity than the relations of a Member to his constituents.2 The discreet veil which local British parties, particularly the Conservatives, usually succeed in drawing over their internal processes compounds the obscurity so that generalizations about the pattern of influence and dissent within the parties are frequently based on exanples which are outdated or only superficially known. It therefore should be instructive to examine rather closely the prolonged dispute which arose between Nigel Nicolson and his constituents at Bournemouth as a result of the Suez crisis of 1956. A close study of this dispute is possible because events came closer to the surface than usual and the present writer was able to discuss
Land Development under the Threat of Taking

This paper presents a model of the land developer's response to the threat of regulatory taking. It shows that the threat of regulation affects development timing and density differently than the regulation imposed with certainty. Planned development proceeds at a more rapid pace under the taking threat, whereas the development density varies systematically by location in a spatial land market. Further, property on which regulations are actually imposed will be developed later than planned when the demanded density is falling over time. Regulated property, however, may be developed even more quickly than planned when the demanded density is rising over time.
Case study: robotic person following using fuzzy control and image segmentation

The paper proposes a scheme for amobile robot to follow a person in reasonably complex dynamic environments. The scheme consists of an image processing technique for person identification, and a fuzzy controller for following the person. The identification process utilizes image color, shape characteristics, and a region growing technique. The fuzzy logic controller receives image data such as the mass, center of mass, and their rates of change to produce steering and speed commands for the robot. A behavior control strategy is also incorporated to cope with several situations, such as hazard, that are not accounted for in the fuzzy controller. Descriptions of the software/hardware as well as experimental setup and results are provided to demonstrate the feasibility of the scheme. © 2003 Wiley Periodicals, Inc.
Mechanisms of referred visceral pain: uterine inflammation in the adult virgin rat results in neurogenic plasma extravasation in the skin

The purpose of this study was to investigate the mechanisms of referred pain observed in female patients with pain from the reproductive organs. We developed a model of inflammatory uterine pain in the rat. Inflammation of the uterus in rats pretreated with Evans Blue Dye resulted in dye extravasation in the skin over the abdomen, groin, lower back, thighs, perineal area and proximal tail, thus providing for the first time evidence for the trophic changes observed in the area of referred visceral pain in an animal model of uterine pain. The neuronal pathways mediating the observed dye extravasation in the skin after uterine inflammation may include dichotomizing afferent fibers, afferent-afferent interactions via a spinal cord pathway or a sympathetic reflex. This model will allow to gain further insight into the mechanisms of referred pain and the trophic changes observed in the area of referred pain in visceral disease.
Treatment of active refractory rheumatoid arthritis with humanized monoclonal antibody campath‐1h administered by daily subcutaneous injection

Objective. To investigate the dose tolerance and potential clinical activity of a humanized antilymphocyte monoclonal antibody, CAMPATH-1H (C1H), in patients with active, refractory rheumatoid arthritis (RA). Methods. Thirty adult patients with active, refractory RA were treated in an open-label, 3-center, dose-escalation study of subcutaneously injected C1H. Six patients were assigned to each of 5 dosage groups (0.3, 1.0, 3.0, 10.0 or 30.0 mg/day), and received 10 daily injections of C1H over a 12-day period. Results. Side effects occurred primarily during the first 1–2 days of dosing, and included mild fever, chills, nausea, vomiting, headache, and, in a minority of patients, hypotension. All patients developed some discomfort at the injection site. Self-limited infections occurred in 5 patients during the 6-month study period. Peripheral blood lymphocyte counts fell promptly after initial dosing and recovered slowly, usually over 2–3 months. Serum antibodies to C1H developed in 54% of patients following treatment. Clinical improvement was observed in 56% of patients, based on the composite Paulus criteria, with a median time-to-response of 22 days and a median response duration of 32 days. Conclusion. C1H is a lymphocyte-depleting antibody that exhibits biologic potency when administered subcutaneously to patients with refractory RA. Its use is associated with mild to moderate toxicity and short-term amelioration of disease activity.
Time reversal for systems with internal symmetry

Wigner time reversal implemented by antiunitary transformations on the wavefunctions is to be refined if we are to deal with systems with internal symmetry. The necessary refinements are formulated. Application to a number of physical problems is made with some unexpected revelations about some popular models.
A completely duality invariant effective action of N = 4 heterotic strings

Abstract We find a low energy effective action for N = 4 strings manifestly invariant under the full O(6,22, Z ) internal duality group. That theory is uniquely specified by its gauge symmetry, which turns out to be an infinite dimensional general Kac-Moody algebra. On any string background the Higgs mechanism leaves only finitely many light fields. The corresponding mass spectrum is studied, and shown to agree with string theory. Orbifold truncations to N = 1, 2 theories are discussed.
Mortgage Lending Discrimination and the Decision to Apply: A Methodological Note

Previous studies of lenders' decisions to accept or reject loan applications have not accounted for the possibility that lenders discourage written applications from members of protected classes, i.e., prescreening. This paper discusses how prescreening and self-selection may bias the measurement of discrimination. Estimation techniques are developed that test and correct for such bias whether or not information is available on non-applicants.
Toward Attenuation of Self-Sustained Oscillations of a Turbulent Jet Through a Cavity

Several attenuation configurations are assessed, involving the following concepts: generating streamwise vorticity, dephasing the azimuthal coherence of the jet, and reducing rigidity of the jet separation edge. By proper design, effective attenuation of the discrete frequency components of the oscillation can be achieved. For cases where there is not complete attenuation, the phase condition corresponding to maximum relative amplitude of the oscillation is maintained, the disturbance phase speed is essentially unaltered, and there is a proportional reduction in amplitude along the jet, including the initial fluctuation level at separation.
A Comparison of Metoclopramide Vs. Droperidol/Phenobarbital for Emesis Induced by Chemotherapy

Chemotherapy-induced nausea and vomiting cause morbidity and poor compliance among patients receiving intensive cancer chemotherapy. High-dose antiemetic regimens, while effective, add significantly to the cost of treatment. This study compares the efficacy and cost of high-dose metoclopramide with a combination of phenobarbital and droperidol. All patients treated were naive to prior chemotherapy, and all patients received treatment regimens containing cisplatinum. Both antiemetic regimens proved equally efficacious in suppressing emesis, but the phenobarbital/droperidol combination achieved a 100-fold decrease in cost.
Varicella zoster with extended prodrome: a case series.

Abstract Background Traditionally, varicella zoster (herpes zoster) is believed to have a prodrome of 1-3 days. The objective of our article is to emphasize the importance of including herpes zoster in the differential diagnosis of unilateral pain syndromes without vesicular lesions present for >3 days. Methods/Results We report a case series from one primary care physician's practice at a tertiary-care teaching hospital documenting herpes zoster prodromes of 6-18 days. Conclusions Our findings expand the clinical picture of herpes zoster, which hopefully will lead to cases of improved diagnoses that translate into the timely and cost-effective implementation of appropriate treatment.
Anti‐receptor antibody‐induced suppression of murine H‐Y‐specific delayed‐type hypersensitivity responses

A putative anti-H-Y receptor antiserum (ARA) was raised in C57BL/6 male mice against splenic T lymphocytes from syngeneic females immunized against H-Y antigen. When this antiserum is given i.v. to C57BL/6 females it prevents the expression of H-Y-specific delayed-type hypersensitivity (DTH). The suppressive activity in ARA was selectively retained on rabbit anti-mouse immunoglobulin columns, and could be absorbed by H-Y-immune spleen cells from C57BL/6 female mice. The abrogation of H-Y DTH reactivity was at least in part due to the generation of suppressor T cells which are generated by ARA in naive female mice. ARA-generated suppressor cells specifically ininhibit the induction phase of DTH responses to the H-Y antigen, having no effect on (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific cutaneous sensitivity responses or on DTH responses to minor histocompatibility antigens. Furthermore, there is a requirement for Igh gene homology between the strain producing the ARA and the strain in which the DTH response is induced. Thus, C57BL/6 ARA given to A.BY (H-2b, Igh-1e) or to B.C-8 (H-2b, Igh-1a) mice was unable to suppress homologous H-Y DTH responses in these strains. However, C57BL/6 ARA induced suppressor cells in B.C-8 mice which were capable of inhibiting H-Y DTH responses when adoptively transferred to C57BL/6 females.
A Reexamination of Protoliteracy through an Analysis of Modern Chinese Character Use

Chinese characters are often viewed as a premodern or incomplete form of literacy. Authors with an autonomous view of literacy view Chinese as a concrete, homeostatic language inadequate for use in abstract thought and movement toward mass literacy. Even those with an ideological model framework propose that the intrinsic nature of Chinese characters identifies it as an elite language of gentry and political rulers. This study reexamines this view of Chinese characters as a protoliteracy by investigating recent national literacy rates, economic trends, and relevant literature for East Asian nations that use Chinese characters as an integral part of their written language. The author argues for caution in using the protoliteracy paradigm for Chinese language reform because modern Chinese is associated with high levels of mass literacy and economic prosperity. In addition, recent cognitive and historical literature suggests Chinese characters are used in languages because of their advantages for abstract th...
Supply chain agility: Securing performance for Chinese manufacturers

Abstract This study develops and empirically tests a conceptual framework to investigate the antecedents of manufacturers' supply chain agility and the connection of their agility with performance in an emerging economy. Drawing upon the information theory, this study argues that technical (IT capability) and relational factors (information sharing and trust, and operational collaboration) are the antecedents of a manufacturer's supply chain agility. This study also posits that cost efficiency mediates the relationship between agility and performance based on transaction cost economics. Employing path analysis, this study shows that strong associations exist between a manufacturing firm's IT capability and operational collaboration with suppliers and its supply chain agility. The results also indicate the significant mediating effect of cost efficiency between the manufacturer's supply chain agility and performance. Implications are discussed and future research directions are also suggested.
Detection of a marker layer in a 7YSZ thermal barrier coating by femtosecond laser-induced breakdown spectroscopy

Abstract A new technique for detection of thickness loss in thermal barrier coatings caused by erosion or foreign/domestic object damage has been demonstrated for a 7YSZ thermal barrier coating. The thickness loss was assessed via femtosecond laser-induced breakdown spectroscopy (fs-LIBS) inspection for a marker layer of gadolinium zirconate, embedded at a critical depth within the 7YSZ coating. Spectroscopic detection of the marker layer was possible at fluence levels as low as 18 J cm − 2 , which is about 11 times the ablation threshold fluence for 7YSZ. The surface damage caused by the laser pulses was minimal and consisted of extremely small individual circular craters with approximate diameter of 30 μm. Further, the laser action also did not cause any cracking in the 7YSZ layer. The minimal collateral damage associated with fs-laser pulses is one of the major advantages of fs-LIBS for spectroscopic characterization of thermal barrier coatings.
Mentoring Support and Relational Uncertainty in the Advisor-Advisee Relationship.

We examine the extent to which career mentoring and psychosocial mentoring received from their advisors relates to advisee perceptions of advisor–advisee relational uncertainty. Doctoral students (N = 378) completed the Academic Mentoring Behaviors Scale (Schrodt, Cawyer, & Sanders, 2003), the Mentoring and Communication Support Scale (Hill, Bahniuk, Dobos, & Rouner, 1989), and the Relational Uncertainty Scale (Knobloch & Solomon, 1999). The results of a series of Pearson correlational analyses indicate that advisees' reports of received career mentoring and psychosocial mentoring from their advisors are negatively related to their advisor–advisee relational uncertainty. These findings emphasize further the importance of advisors' provision of mentoring support for their advisees.
A New Genus and New Tribe of Cicada From South America (Hemiptera: Cicadoidea: Cicadidae) with a Note on the Taxonomic Position of Ahomana Distant, 1905

Abstract The cicada genus Chilecicada Sanborn n. gen. is described to accommodate the Chilean species, C. occidentis (Walker, 1850) n. comb., which is redescribed and illustrated, with the first description of the female. The new genus is placed in the Chilecicadini Sanborn n. tribe. Ahomana Distant, 1905 is transferred from the Tibicinini within the Tibicininae to the Carinetini within the Cicadettinae. A lectotype is designated for Ahomana neotropicalis Distant, 1905.
NUCLEAR MAGNETIC RESONANCE IN SOLID HELIUM-3

Nuclear magnetic resonance experiments have been performed in solid ${\mathrm{He}}^{3}$ at constant molar volumes in the $\ensuremath{\alpha}$ and $\ensuremath{\beta}$ phases at various magnetic fields and temperatures by the spin-echo method. The self-diffusion coefficient $D$ as well as the relaxation times ${T}_{1}$ and ${T}_{2}$ have been determined. $D$ is observed to obey the Arrhenius equation as the temperature is lowered in the $\ensuremath{\alpha}$ phase, but at a low enough temperature it becomes temperature independent and depends only on the density. The activation energy for diffusion correlates well with that determined from specific heat measurements. At high magnetic fields ${T}_{1}$ and ${T}_{2}$ are observed to obey the Bloembergen, Purcell, and Pound relationships characteristic of relaxation caused by diffusion. At low magnetic fields, ${T}_{1}$ becomes temperature independent as the temperature is lowered, and is observed to depend on magnetic field as $\mathrm{exp}(\frac{{H}^{2}}{H_{0}^{}{}_{}{}^{2}})$, implying that the relaxation is from Zeeman to exchange systems. Values of the exchange integral $J$ are deduced from temperature-independent diffusion, field-dependent relaxation, and rigid-lattice values of ${T}_{2}$, and show fair agreement internally. No agreement can be obtained with values of $J$ deduced from observations of departures from Curie's law, the values here reported being much smaller.
N2 and Ar broadening and line mixing in the P and R branches of the v3 band of CH4

Abstract N2- and Ar-broadened spectra of the allowed P- and R-branch manifolds for J ⩽ 10 in the v3 band of CH4, have been recorded from the Doppler limit to ∼ 67 kPa at T = 295 K using a tunable difference-frequency laser spectrometer. The broadening coefficients exhibit larger variations among the tetrahedral components in the R-branch manifolds than in the P branch, which in turn are very similar to the Q branch previously measured [A.S. Pine, J. Chem. Phys. 97, 773 (1992)]. The broadenings for Ar are uniformly 88(1)% of those for N2. Line intensities, pressure shifts and Dicke narrowing coefficients are also obtained. Strong line mixing among the blended tetrahedral components is observed, and an analysis is presented restricting line coupling among transitions with the same nuclear spin A, E or F symmetry with the sum of the mixing coefficients for a given symmetry in a J manifold constrained to zero.
Distribution of mRNAs encoding the arylhydrocarbon receptor, arylhydrocarbon receptor nuclear translocator, and arylhydrocarbon receptor nuclear translocator-2 in the rat brain and brainstem.

Dioxin exposure alters a variety of neural functions, most likely through activation of the arylhydrocarbon receptor (AhR) pathway. Many of the adverse effects, including disruption of circadian changes in hormone release and depressed appetite, seem to be mediated by hypothalamic and/or brainstem neurons. However, it is unclear whether these effects are direct or indirect, because there have been no comprehensive studies mapping the expression of components of the AhR pathway in the brain. Therefore, we used a sensitive in situ hybridization histochemical (ISHH) method to map the neural expression of AhR mRNA, as well as those of the mRNAs encoding the AhR dimerization partners, arylhydrocarbon receptor nuclear translocator (ARNT) and ARNT2. We found that AhR, ARNT, and ARNT2 mRNAs were widely distributed throughout the brain and brainstem. There was no neuroanatomic evidence that AhR is preferentially colocalized with ARNT or ARNT2. However, ARNT2, unlike ARNT expression, was relatively high in most regions. The most noteworthy regions in which we found AhR, ARNT, and ARNT2 mRNA were several hypothalamic and brainstem regions involved in the regulation of appetite and circadian rhythms, functions that are disrupted by dioxin exposure. These regions included the arcuate nucleus (Arc), ventromedial hypothalamus (VMH), paraventricular nucleus (PVN), suprachiasmatic nucleus (SCN), nucleus of the solitary tract (NTS), and the dorsal and median raphe nuclei. This neuroanatomic information provides important clues as to the sites and mechanisms underlying the previously unexplained effects of dioxins in the central nervous system. J. Comp. Neurol. 427:428–439, 2000. © 2000 Wiley-Liss, Inc.
The influence of microstructure on the susceptibility of titanium alloys to internal hydrogen embrittlement

Beta-processed near-alpha titanium alloys with a large colony microstructure were found to be susceptible to internal hydrogen embrittlement under conditions of sustained loading or fatigue cycling with a dwell period at peak load. The embrittlement occurs by localized increases in hydrogen content at the tips of long, blocked shear bands developed during time-dependent plastic deformation. The key microstructural features responsible for the embrittlement process have been determined to be a large transformed beta colony size and a fine, discontinuous distribution of beta phase within the colony. Alpha-beta alloys that contain thick, continuous beta platelets were determined to be immune to embrittlement. The results are consistent with a previously-proposed model for the embrittlement process.
TENTH-ORDER QED CONTRIBUTION TO THE ELECTRON g 2 AND HIGH PRECISION TEST OF QUANTUM ELECTRODYNAMICS

This paper presents the current status of the theory of electron anomalous magnetic moment ae ≡(g-2)/2, including a complete evaluation of 12,672 Feynman diagrams in the tenth-order perturbation theory. To solve this problem, we developed a code-generator which converts Feynman diagrams automatically into fully renormalized Feynman-parametric integrals. They are evaluated numerically by an integration routine VEGAS. The preliminary result obtained thus far is 9.16 (58) (α/π)5, where (58) denotes the uncertainty in the last two digits. This leads to ae(theory) = 1.159 652 181 78 (77) ×10-3, which is in agreement with the latest measurement ae (exp:2008) = 1.159 652 180 73 (28) ×10-3. It shows that the Feynman–Dyson method of perturbative QED works up to the precision of 10-12.
Protein flexibility and adaptability seen in 25 crystal forms of T4 lysozyme.

The structures of various mutants of T4 lysozyme have been determined in 25 non-isomorphous crystal forms. This provides an unusually diverse data base to compare the structures and dynamics of a closely related set of proteins in different crystal packing environments. In general, the more tightly packed crystals diffract better than those that are highly hydrated although the wild-type crystal form is an exception. The ability of the protein to form a relatively open but stable lattice may help explain why many of the mutants crystallize in this form. In different crystalline environments, the lysozyme molecules associate with 2-fold, 3-fold, 4-fold, and 5-fold symmetry, as well as with various types of screw associations. A "back-to-back" dimeric association, and a "head-to-tail" 2(1) screw association, are especially common, each occurring in more than half a dozen crystal forms. The 4-fold and 5-fold modes of association are closely related and provide an example of quasi-equivalent association as envisaged by Caspar and Klug. In different crystal environments the lysozyme molecules display a range of over 50 degrees in the hinge-bending angle between the amino and carboxy-terminal domains. Large variations in the hinge-bending angle are observed not only for lysozymes with mutations in the hinge region, but for molecules with mutations far from this site. This suggests that hinge-bending is an intrinsic property of the lysozyme molecule and is not an artifact due to mutation. As the hinge-bending angle increases about 15 degrees beyond that seen in wild-type there is a distinct conformations change in the side-chains of five residues in the hinge-bending region. Changes in the backbone are localized near residues 13, 59 and 80, but do not include significant changes in (phi, psi). Comparison of the different structures indicates that crystal contacts perturb the backbone structure of the protein by 0.2 to 0.5 A. These perturbations are of the same magnitude for helices and beta-sheet strands, suggesting that protein structures can be defined and maintained equally well by hydrogen-bonding (i.e. strand-strand) or by non-hydrogen-bonding (i.e. helix-helix) interactions. The discrepancies between the lysozyme structures in different crystallographic environments are in line with other comparisons of independently determined protein crystal structures. They suggest that protein structures in general are subject to low energy changes in conformation of 0.2 to 0.5 A.(ABSTRACT TRUNCATED AT 400 WORDS)
Dehydration in the elderly: strategies for prevention and management

Dehydration is the most common fluid and electrolyte disturbance among the elderly population today. It is defined as a state of diminished total body water content and is associated with high morbidity and mortality rates. Such health outcomes highlight the urgent need for effective screening and prevention in the primary care arena. Myriad predisposing factors make the elderly more vulnerable to dehydration. On physical examination, many of the classic signs of dehydration may be present among normally hydrated older populations, highlighting the need for an age-appropriate assessment. In this regard, health care practitioners with a working knowledge of pertinent underlying pathophysiology and relevant predisposing factors will more readily identify high-risk clients and implement successful preventative strategies. Prompt intervention can dramatically affect health care outcomes among high-risk populations and go a long way in providing high-quality, cost-effective health care.
Confrontation as moral drama: The Boston massacre in rhetorical perspective

The rhetoric of the American Revolution can offer insights not only into the function of persuasion in that monumental social movement, but also into the function of confrontation within agitational movements. The Boston Massacre, like later confrontations in the civil rights movement, the student power movement, and the anti‐war movement, had a persuasive impact far out of proportion to the objective importance of the incident. Because it served as a moral drama, the Boston Massacre helped to define the larger conflict between America and England in terms of good versus evil, liberty versus tyranny. The real significance of the Boston Massacre is not to be found in the riot itself, but in the rhetoric it fostered.
A Physical Description of CdSe TFT Operation

ABSTRACT CdSe TFT's have been built and tested in which the electron mobility values inferred from Weimor's description of the TFT in some cases exceed the bulk single- crystal values. A two-gate TFT was tested in which the possibility of charge injection can be eliminated. It had better modulation when operated with the input and output circuits isolated than when operated in the conventional mode. A physical model based on electric field excitation of carriers is presented which is compatible with these results and also is consistent with the dependence of transconductance on temperature and illumination.
Statistical Hydrodynamical Model Of Perfusion For NMR Studies

Since August Krogh's original work in 1919, organ perfusion has been modelled extensively after what is known as "single capillary" model. In these models, the perfused organ is conceptualized as composed of identical building blocks, each consisting of either a circular or a hexagonal tissue cylinder supplied by a single capillary. A vast literature has grown up on such models, the most noteworthy of which are listed in references. Krogh's original model, shown in Fig. 1, consists of identical parallel capillaries each supplying it's own circular tissue cylinder. A variant of Krogh cylinder model for a well-perfused organ with parallel capillaries with equal flow and supplying hexagonal axisymmetric tissue columns of equal lengths is that of Bassingthwaighte and is shown in Fig. 2. Another approach to perfusion modelling is that of compartmental analysis where the perfused organ is divided into a blood and a tissue compartment. Various assumptions are then made regarding the nature of these two compartments. The tissue compartment is usually considered to be well stirred and for the blood compartment, a linearly distributed capillary bed is assumed. This is equivalent to a single capillary with an axial variation of concentration down its length. Usually the mixing in the radial direction is assumed to take place infinitely rapidly. Most important of these models are those of Renkinll , Johnson and Wilson, and Levitt. The model presented here is shown in Fig. 3, and assumes that the blood compartment, where the microcirculation takes place, is a random network of interconnected microchannels, the network being in contact with the tissue compartment. Blood from the arterial side enters this capillary network in which microcirculation takes place with or without exchange with the tissue compartment, and finally the perfused blood exits at the venus end. This clearly departs from the single capillary models since no assumption is made as to the orientation, distribution and identity in structure of the microcirculatory capillaries. For the same reason, this also differs from the linearly or any other deterministically distributed capillary bed of the compartmental analysis. Moreover, the concentration distribution in such a network is not inferred or prescribed, but is calculated from the basic hydrodynamics of the medium. This leads to a concentration distribution in both parallel and perpendicular (to mean flow) directions in terms of the dispersion of statistical hydrodynamics.
Kinetics and mechanisms of drug action on microorganisms X: Action of spectinomycin on escherichia coli by microbial kinetics

The steady-state growth of Escherichia coli cultures, N = N0ek0t, is slowly inhibited by spectinomycin to a new steady state with a new rate constant, kapp. The kapp. is linearly dependent on drug concentration, S, above a certain minimum concentration of spectinomycin, S*; i.e., kapp = k0 - kS(S - S*). This minimum concentration is a function of the concentration of the media and can be assigned to binding or removal of microbiologically effective spectinomycin as protonated material by the components of the media. The logarithm of the inhibitory constant, ks, linearly increases with the pH of the media to pH 7.6, and this implies that only uncharged material is biologically active. The slow rate of achievement of a drug-equilibrated, steady-state, microbial generation rate can be reconciled with a relatively rapid reequilibrated rate on dilution with fresh media by postulating depletion of a cell-generated vital metabolite linked to the growth rate of the microorganism.
COMPLEX PERIODIC MARKET CYCLES

ABSTRACT Market cycles are conceptualized from the viewpoint of users. Distinctions are made between part-time and full-time traders, number of market days in a market week, location of the trader, routes used to frequent markets, the order of the good, and short-term changes in supply and demand. A number of complex market cycle types are identified with the aid of graph theoretic notions. Ecological complementarity within a market cycle framework is measurable in matrix format. An index of regional specialization can measure ecological or economic complementarity among regions.
Effect of Maturation on 31P Magnetic Resonance Spectroscopy of the Rabbit Masseter Muscle

This work studies the dynamic metabolic changes of the rabbit masseter muscle during post-natal development. The composition and proportion of oxidative and glycolytic muscle fibers alter during maturation. The masseter muscle, as most muscles of the craniofacial region, exhibits unusual development in composition of isoforms of myosin. The effect of this unusual composition on the dynamic metabolic properties of the masseter muscle have not been assessed. The metabolism of the rabbit masseter muscle was studied by means of 31P-nuclear magnetic resonance (NMR) spectroscopy. Contraction was elicited by electrical stimulation of the muscle in the anesthetized animal. Five animals were studied at 8 weeks and 24 weeks so that both the juvenile and adult stages could be evaluated. The dynamic biochemical changes in the masseter muscle were studied by the analysis of NMR spectra. A single-turn surface coil (copper) was used, and the original signal was treated with Fourier transforms to obtain 31P spectra. The low signal-to-noise ratio required averaging 16 acquisitions (acquisition time = 400 msec, repetition rate = 1.8 sec) in 30 sec and then obtaining continuous spectra for 27 min. Each averaged spectrum demonstrated five peaks: inorganic phosphate (Pi), creatine phosphate (PCr), and three peaks related to adenosine triphosphate (ATP). The protocol involved recording an initial three-minute rest period, stimulating the muscle at 5 Hz for 3 min twice, separated by three-minute rest periods, and stimulating the muscle at 50 Hz twice for 3 min separated by rest periods. The Pi/PCr ratio increased significantly in the adult masseter during both 5-Hz stimulations, evoking twitching, and the first 50-Hz stimulation, evoking tetany (repeated ANOVA, P < 0.05). The resting pH (6.96 +/- 0.13) was significantly lowered during both twitching (6.85 +/- 0.10; P < 0.0038) and tetany (6.55 +/- 0.13; P < 0.0001), but only in the adult masseter muscle. These finding suggest that the adult masseter muscle possesses more glycolytic fibers as it modifies its metabolism during postnatal development.
Gelation properties of fatty fish processed with or without added sodium chloride, cryoprotectants and antioxidants

Abstract The effect of 3% (w/w) added salt; an antioxidant mixture consisting of 0·02% (w/w) t-butylhydroquinone (TBHQ) (based on total lipid), 0·2% (w/w) ascorbate and 0·2% (w/w) sodium tripolyphosphate (STPP) added during the grinding and washing steps; and a cryoprotectant mixture of 4% (w/w) sorbitol, 4% (w/w) sucrose, and 0·2% (w/w) STPP added just prior to gel formation were tested for their effects on true strain and stress at breakage and fold test scores of washed bluefish and mackerel mince. The addition of 3% (w/w) NaCl and the cryoprotectant mixture increased true strain values under all conditions; fold test scores followed similar patterns. The antioxidant mixture gave increased strain values in the absence of the added 3% (w/w) NaCl in both bluefish and mackerel prepared with or without cryoprotectants; in the case of mackerel, the antioxidant mixture gave higher true strain values in the presence of salt as well. Stress values were highly variable and no clear trends were observed with bluefish with any of the parameters; seven out of eight samples of mackerel had lower stress values in the presence of the antioxidant mixture. The results may be useful in designing a process for improving the gelation characteristics of fatty fish.
Epidermal carcinogenesis studies of synthetic fossil fuel materials in mice.

Abstract Skin tumor response in mice to solvent fractions of heavy distillate (HD) from a solvent-refined coal (SRC-II) process indicated that the basic tar and neutral tar were the most carcinogenically potent fractions. Assays of another SRC-II coal liquid that had been fractionally distilled indicated that the carcinogenicity of this material for mouse skin is due to that portion boiling above 371°C (700°F), and that the carcinogenic potency of the material increased with boiling point. Samples of the 399–427°C (750–800°F) distillate were nitrosated to destroy primary aromatic amines and were chemically fractionated to assess the carcinogenicity of chemical class fractions of these complex mixtures. Data from these assays indicated that neutral polycyclic aromatic hydrocarbons (PAH) and nitrogen-containing polycyclic aromatic compounds (NPAC) both contribute to the carcinogenicity of this distillate.
Reply 1: An assessment of the preconceptional mitochondrial hypothesis.

Sir, We found Dr van Noord's preconceptional mitochondrial hypothesis interesting particularly in line with a recent report linking polymorphisms of two DNA base excision repair genes (XRCC1 and hOGG1) to breast cancer risk in daughters born to older mothers (Hodgson et al, 2003). Manganese superoxide dismutase (MnSOD) may impair the mitochondria's ability to reduce oxidative stress (Oberley and Oberley, 1997). MnSOD has been linked to breast cancer (Ambrosone et al, 1999), and may be another pathway through which older maternal age may function. Further support for this hypothesis comes from a recent study that found mitochondrial DNA damage in breast cancer tissue (Richard et al, 2000). To test this hypothesis, we analysed the association of parental age with breast cancer risk using data from the Shanghai Breast Cancer Study (SBCS), and the results are in shown Table 1 . After adjustment for established breast cancer risk factors and pregnancy order, we did not find an association between older maternal or paternal age and premenopausal breast cancer in our low-risk population. Additional adjustment for paternal age resulted in a nonsignificantly elevated risk of breast cancer associated with older maternal age. All perinatal information was based on maternal report. Table 1 Odds ratios of breast cancer associated with maternal age and paternal age Although we collected information on whether the mother had a threatened miscarriage with the index pregnancy, too few women reported this adverse event (six case mothers, 13 control mothers) to provide a stable risk estimate. Other studies may have sufficient numbers of mothers to investigate this aspect of Dr van Noord's hypothesis. Dr van Noord argued that insulin-like growth factor- I (IGF-1) might be unlikely to explain the inconsistent findings on birth weight and breast cancer risk in the literature, since the link between IGF-I and breast cancer risk has been found primarily in premenopausal women, while the high birth weight-breast cancer association has been seen among pre- and postmenopausal women. A previous report from the SBCS showed that elevated levels of IGF-I were associated with an increased risk of breast cancer among all women, but the association was more pronounced among women diagnosed premenopausally and among women with a high body mass index or waist-to-hip ratio (Yu et al, 2001). We found in a large US study that high birth weight was associated with an elevated risk among premenopausal women (OR=1.7, 95% CI 1.1–2.5), but a nonsignificantly reduced risk among postmenopausal women (OR=0.6, 95% CI 0.3–1.1) (Sanderson et al, 1996). Therefore, IGF-I as a potential explanation for the birth weight-breast cancer relationship cannot be ruled out.
Highway Noise Barriers: 1994 Survey of Practice

Highway traffic noise is an ever-increasing problem for transportation agencies. The challenge presented to transportation agencies is to incorporate noise abatement into the highway environment without compromising the aesthetic integrity of the surrounding communities. In an effort to guide highway designers, a survey of practice was sent to all state transportation agencies and their equivalents in Puerto Rico and Ontario, Canada. The portions of the survey regarding noise-barrier materials, aesthetic visual quality in design, and public involvement in the design process are discussed in this paper. The literature review revealed a long-standing effort throughout Europe to incorporate many aesthetic features into noise-barrier systems and to use public preferences to guide design. Many new products that provide aesthetically pleasing noise barriers, in addition to the noise-level reductions required of transportation agencies, are now available. Innovative and versatile methods of using standard materials, such as concrete, have provided a continual supply of barrier designs. A multidisciplinary collaboration (including citizen representatives) in the design process has proved to be an effective method of ensuring that the best design is implemented for both sides of the highway environment. Collectively, transportation agencies, private industry, and institutional research programs should work together to advance the knowledge available in noise research and to further develop the aesthetic visual quality of the highway environment.
Collaboration between Writers and Graphic Designers in Documentation Projects.

Few, if any, studies on collaboration examine interactions between software manual writers and graphic designers. This study analyzes these collaborations, inquiring into the ways in which writers' and designers' processes of collaboration directly affect the form and substance of a finished manual. We argue that when these developers have dialogue, draft iteratively, and jointly make decisions, they produce manuals that could not possibly be developed through linear, assembly-line collaborative processes. We characterize three possible models of collaboration—assembly line (linear drafting), swap meet (iterative drafting and joint problem solving), and symphony (codevelopment in every aspect)—and use as a case study our own collaboration in developing a manual, detailing the concerns that writers and designers bring to a manual project. Analyzing our collaboration as an example of a swap-meet model, we examine four design problems that we faced and explain the ways in which our collaborative processes un...
Analysis of vitamin B12 in seawater and marine sediment porewater using ELISA

Vitamin B12 (B12) is a set of closely related organocobalt compounds required by phytoplankton. A highly sensitive and specific enzyme-linked immunosorbent assay (ELISA) was developed for the determination of B12 in seawater and marine sediment porewater. An antibody directed against B12 was coated on the surface of a 96-well microtiter plate, and horseradish peroxidase (HRP) was used as a labeling enzyme. In the indirect competitive immunoassay format, water samples or standards and a constant amount of HRP-labeled B12 were added into the microtiter plate wells, HRP-labeled and free B12 compete for binding to the plate-bound antibody. After immunoreaction, the immunochemically adsorbed HRP-B12 conjugate was determined by measuring the absorbance produced in a solution containing substrate tetramethylbenzidine (TMB) and hydrogen peroxide. The calibration graph for B12 was linear over the range of 0.4–100 ng/mL (0.3–74 nM; higher concentrations were not evaluated) with a detection limit of 0.2 ng/mL (3s). Coupled with C-18 column extraction–preconcentration, the method is readily applicable to seawater levels (~1–10 pM). No interferences from humic acids, total dissolved organic matter (DOM), and salinity were observed. ELISA determined B12 in coastal seawater and surface tidal flat porewater (0–2 cm) ranged from 4.5–38 pM and 12–47 pM, respectively.
Treatment of type II endoleaks associated with left subclavian artery coverage during thoracic aortic stent grafting.

Objective Increasing experience with thoracic aortic stent grafts has led to a more aggressive approach to thoracic aortic pathologies in the distal aortic arch and proximal descending thoracic aorta. To increase the length of the proximal landing zone, it is sometimes necessary to cover the left subclavian artery with the thoracic stent-graft, introducing the risk of retrograde filling of the excluded aorta from the left subclavian artery. It is currently unclear how best to manage these patients to prevent persistent risk of aneurysm expansion or rupture. We report our experience with a minimally invasive endovascular repair of the covered left subclavian artery. Methods We reviewed prospectively gathered data on all investigational device exemption-approved patients undergoing thoracic aortic stent grafting at the Arizona Heart Institute from 2000 to 2006 (n = 289 patients). Patients had surveillance with a contrast-enhanced computed tomography scan on the first postoperative day and during follow-up at 1, 6, and 12 months. Results A total of 289 patients received thoracic stent grafts during the study: Medtronic Talent (Medtronic, Minneapolis, Minn) (n = 25) or Gore TAG (WL Gore & Associates Inc, Flagstaff, Ariz) (n = 261). The left subclavian artery was covered in 23% of patients (n = 66), of whom 17% had preoperative carotid-subclavian bypass (n = 11/66). Among patients with left subclavian artery coverage, the 30-day mortality was 6.1% (n = 4), procedure-related strokes developed in 3 patients (n = 3, 4.6%), and the incidence of left arm claudication was 7.6% (n = 5), necessitating postoperative carotid-subclavian bypass in 2 patients. Twelve patients (18%) had a type I (n = 6) or II (n = 7) endoleak. Coverage of the left subclavian artery accounted for 71% of the type II endoleaks (n = 5), whereas patent intercostals accounted for the rest (n = 2). Type II endoleaks associated with left subclavian artery coverage were successfully treated by retrograde coil embolization from the left brachial artery (n = 3) or left subclavian artery ligation (n = 1). Conclusion Coverage of the left subclavian artery during thoracic aortic stent grafting is associated with a low incidence of arm complications and type II endoleaks. All type II endoleaks were successfully treated by retrograde coil embolization or ligation of the left subclavian artery. Successful treatment of endoleaks may reduce the risk of aneurysm expansion or rupture.