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Frequency doubling a 140 × 110 mm 40 J sub-ps 1054 nm beam for laser matter interaction studies was investigated at the Central Laser Facility, with efficiencies greater than 60% being achieved. The conversion characteristics (efficiency, beam quality, focusability, and pulse length) for two large 157 mm diameter aperture high quality KDP crystals of thickness 2 mm and 4 mm were studied. Using a fundamental drive beam of two times diffraction limited quality, focal spots of four times the diffraction limit in the frequency doubled beam were achieved and beam degradation effects shown to be minimal.

ZF87/MAZ is a zinc finger-containing transcription factor that was cloned based on its ability to bind to a site within the c-myc P2 promoter. However, its role in the control of c-myc transcription has not yet been well established. Here we have analyzed the effect of ZF87/MAZ overexpression on transcription from the murine c-myc P2 promoter. It was found that when overexpressed in COS cells, ZF87/MAZ significantly represses transcription from P2. The repression is mediated through the ME1a2 element, located at position -86 relative to the P2 transcriptional start site, and is not mediated through either the E2F or the ME1a1 sites. ZF87/MAZ functions as a true transcriptional repressor since it can repress transcription independently of the c-myc promoter, as part of a fusion with the GAL4 protein. The repressive domain within ZF87/MAZ is located in the amino-terminal half of the protein, a region rich in proline and alanine residues. ZF87/MAZ therefore shares features (i.e. a Pro/Ala-rich region) with those of known transcriptional repressor proteins.

The trypsin-like serine proteinase superfamily contains a number of potential therapeutic targets, many of which are unsuitable for routine X-ray crystallographic studies. We have cocrystallized a selection of benzamidine-based inhibitors with bovine trypsin and solved their structures to a resolution of up to 1.7 Å. Despite similar chemical formulas, the inhibitors exhibit a range of diverse binding modes that reflect their inhibitory spectra against the serine proteinases trypsin, thrombin, factor Xa, tissue-type plasminogen activator (tPA) and urokinase (uPA). In contrast to the compact folded conformations of thrombin inhibitors which allow optimal binding in the well-defined hydrophobic S2/S4 pocket of thrombin, those effective against factor Xa exhibit an extended conformation that allows occupation of the S3/S4 region, where hydrophobic and electrostatic interactions can stabilize the conformation. One group of inhibitors containing an N-terminal 2,4,6-triisopropylphenylsulfonyl (TIPPS) moiety show little or no penetration into the S3/S4 subsites of trypsin. These latter sites are occluded in uPA, explaining why this class of compounds is effective against uPA. Despite presenting an extensive hydrophobic surface toward the solvent, the Ki values for TIPPS-containing compounds against trypsin is in the range 10^-7 to 10^-8 M. Comparison of the binding of a bis-benzamidine inhibitor in trypsin and tPA indicate that a shift in potency can be induced by relatively minor changes in binding mode. Implications for the inhibition of these proteinases are discussed.

A series of derivatives of rac-benzenesulfonyl-glycyl-phenylalanine or its ethyl ester with a combination of thioamido/amidino or amidino/amidino substituents in the benzene rings was synthesized as potential inhibitors of factor Xa (fXa). Among these, the racemic 4‘-amidinobenzenesulfonyl-glycyl-4-amidinophenylalanine ethyl ester was found to exhibit the highest affinity for fXa despite the unfavored location of the amidino substituent in the para position. X-ray structural analysis of the trypsin complex with this bis-benzamidine compound revealed a retro-binding mode if compared to those of similar compounds, so far analyzed in complexes with trypsin or fXa. This noncanonical binding mode as well as its slow plasma clearance rates in rats, if compared to those of other benzamidine derivatives, suggests this compound as an interesting new lead structure for the design of fXa inhibitors.

Ornithodorin, isolated from the blood sucking soft tick Ornithodoros moubata, is a potent (Ki = 10(‐12) M) and highly selective thrombin inhibitor. Internal sequence homology indicates a two domain protein. Each domain resembles the Kunitz inhibitor basic pancreatic trypsin inhibitor (BPTI) and also the tick anticoagulant peptide (TAP) isolated from the same organism. The 3.1 A crystal structure of the ornithodorin‐thrombin complex confirms that both domains of ornithodorin exhibit a distorted BPTI‐like fold. The N‐terminal portion and the C‐terminal helix of each domain are structurally very similar to BPTI, whereas the regions corresponding to the binding loop of BPTI adopt different conformations. Neither of the two ‘reactive site loops’ of ornithodorin contacts the protease in the ornithodorin‐thrombin complex. Instead, the N‐terminal residues of ornithodorin bind to the active site of thrombin, reminiscent of the thrombin‐hirudin interaction. The C‐terminal domain binds at the fibrinogen recognition exosite. Molecular recognition of its target protease by this double‐headed Kunitz‐type inhibitor diverges considerably from other members of this intensely studied superfamily. The complex structure provides a model to explain the perplexing results of mutagenesis studies on the TAP‐factor Xa interaction.

Measurement of the adenine nucleotide and inorganic phosphate content of normoxic and ischaemic kidney in vivo has been made, comparing enzymic assay (after freeze-clamping and acid extraction) with quantification by 31P-n.m.r. Both methods give similar results for ATP, and n.m.r. quantification of Pi gives a value 25-50% of that obtained by enzymic assay. ADP, which is largely invisible to n.m.r. in the normoxic kidney, remains invisible during ischaemia despite a 2-3 fold rise in enzymically assayed ADP. N.m.r. and enzymic assay of the acid extracts give similar values for all metabolites measured. The question of ADP binding in the kidney is discussed, as are the implications for the metabolic regulation of ADP-dependent reactions.

A method is described for the determination of the pH of intracellular water based on the distribution of [14C]benzoate (0.01 mM) between intra- and extra-cellular water. Benzoate at higher concentrations (2-10mM) enters the yeast cell in the undissociated form, and its neutralization within the cell can cause a shift of the pH of the intracellular water by more than 1 pH unit. Benzoate causes an accumulation of the two hexose monophosphates of yeast glucose fermentation and a decrease in intermediates beyond phosphofructokinase, suggesting inhibition at this stage. Benzoate also causes a concomitant fall in [ATP]. Phosphofructokinase is inhibited to a greater extent than hexokinase at acid pH. There is a relationship between intracellular pH, phosphofructokinase inhibition and CO2 production, suggesting that the antifungal action of benzoate is caused by an accumulation of benzoate at low external pH, which lowers the intracellular pH into the range where phosphofructokinase is sensitive. The subsequent inhibition of glycolysis causes a fall in [ATP] and thus restricts growth.

A comparative study of electrical performance is made between normal and superconducting multiple conductors, for applications in high-speed, high-density VLSI interconnects and uniplanar MICs. The self-consistent electromagnetic analysis is presented, which can handle the multiconductors as normal dielectrics, with high real or complex conductivity in the electromagnetic simulation. Examples of interconnecting lines and multiple uniplanar waveguides are shown for dispersion and losses. Extremely low losses and dispersion of superconducting multiple lines, over a very wide frequency range, demonstrate promising potential for high-speed interconnects.

Using the three-dimensional structures of thrombin and the leech-derived tryptase inhibitor (LDTI), which does not inhibit thrombin, we were able to construct three LDTI variants inhibiting thrombin. Trimming of the inhibitor reactive site loop to fit thrombin's narrow active site cleft resulted in inhibition constants (Ki) in the 10 nM concentration range; similar values were obtained by the addition of an acidic C-terminal peptide corresponding to hirudin's tail to LDTI. Combination of both modifications is additive, resulting in very strong inhibition of thrombin (Ki in the picomolar range). On the one hand, these results confirm the significance of the restricted active site cleft of thrombin in determining its high cleavage specificity; on the other, they demonstrate that sufficient binding energy at the fibrinogen recognition exosite can force thrombin to accept otherwise unfavorable residues in the active site cleft. The best inhibitor thus obtained is as effective as hirudin in plasma-based clotting assays.

The x-ray crystal structure of recombinant leech-derived tryptase inhibitor (rLDTI) has been solved to a resolution of 1.9 A in complex with porcine trypsin. The nonclassical Kazal-type inhibitor exhibits the same overall architecture as that observed in solution and in rhodniin. The complex reveals structural aspects of the mast cell proteinase tryptase. The conformation of the binding region of rLDTI suggests that tryptase has a restricted active site cleft. The basic amino terminus of rLDTI, apparently flexible from previous NMR measurements, approaches the 148-loop of trypsin. This loop has an acidic equivalent in tryptase, suggesting that the basic amino terminus could make favorable electrostatic interactions with the tryptase molecule. A series of rLDTI variants constructed to probe this hypothesis confirmed that the amino-terminal Lys-Lys sequence plays a role in inhibition of human lung tryptase but not of trypsin or chymotrypsin. The location of such an acidic surface patch is in accordance with the known low molecular weight inhibitors of tryptase.

In studies of the metabolism of isolated hepatocytes, it is often necessary to measure the concentrations of cell constituents both in cells and medium. When hepatocytes are separated in the special tubes of Hems, Lund & Krebs (1975) (Biochem. J. 150, 47–50), they lose much glucose, urea and Na+, whereas there is no loss of K+, glutamate, aspartate and adenine nucleotides. Cell water is also lost, as measured by the distribution of 3H2O. This loss is mainly due to an exchange of cell water with the aqueous solution in the stems of the tubes through which the cells pass on centrifugation. In general, substances are lost only when the intracellular concentration is equal to, or lower than, the extracellular concentration. Probably solutes are lost because they travel with the water unidirectionally out of the cell. A loss of solute does not occur when the cells are centrifuged in conical tubes with a layer of silicone oil between the cell suspension and the deproteinizing layer. The reasons for the loss occurring in the special separation tubes are discussed.

1. Isolated hepatocytes were used to establish the reasons for the accumulation of aspartate, previously observed when the isolated rat liver was perfused with ethanol in the presence of alanine or ammonium lactate. 2. The isolated cells did not form aspartate when incubated with alanine and ethanol, but much aspartate was formed on incubation with ammonium lactate and ethanol. 3. Urea was the main nitrogenous product on incubation with alanine, in contrast with the perfused liver, where major quantities of NH4+ are also formed. When the formation of urea was nullified by the addition of urease, alanine plus ethanol caused aspartate formation, indicating that aspartate formation depends on the presence of critical concentrations of NH4+. 4. The accumulated aspartate was present in the cytosol. Ethanol halved the content of 2-oxoglutarate in the cytosol and more than trebled that of glutamate in the mitochondria. 5. The findings support the assumption that 2-oxoglutarate formed by the mitochondrial aspartate aminotransferase is not translocated to the cytosol in the presence of ethanol and NH4+, because it is rapidly converted into glutamate, the dehydrogenation of ethanol providing the required NADH. Aspartate, however, is translocated to the cytosol and accumulates there because of the lack of stoicheiometric amounts of oxoglutarate.

The recent structure determination of the catalytic domain of tissue-type plasminogen activator (tPA) suggested residue Arg174 could play a role in P3/P4 substrate specificity. Six synthetic chromogenic tPA substrates of the type R-Xaa-Gly-Arg-p-nitroanilide, in which R is an N-terminal protection group, were synthesized to test this property. Although changing the residue Xaa (in its L or D form) at position P3 from the hydrophobic Phe to an acidic residue, Asp or Glu, gave no improvement in catalytic efficiency, comparative analysis of the substrates indicated a preference for an acidic substituent occupying the S3 site when the S4 site contains a hydrophobic or basic moiety. The 2.9 A structure determination of the catalytic domain of human tPA in complex with the bis-benzamidine inhibitor 2, 7-bis-(4-amidinobenzylidene)-cycloheptan-1-one reveals a three-site interaction, salt bridge formation of the proximal amidino group of the inhibitor with Asp189 in the primary specificity pocket, extensive hydrophobic surface burial, and a weak electrostatic interaction between the distal amidino group of the inhibitor and two carbonyl oxygens of the protein. The latter position was previously occupied by the guanidino group of Arg174, which swings out to form the western edge of the S3 pocket. These data suggest that the side chain of Arg174 is flexible, and does not play a major role in the S4 specificity of tPA. On the other hand, this residue would modulate S3 specificity, and may be exploited to fine tune the specificity and selectivity of tPA substrates and inhibitors.

In order to explore the molecular basis for the glycopeptide specificity of legume lectins, we have developed an experimental system in which specific amino acid alterations can be introduced into the carbohydrate binding site of pea lectin. This system is based on the production of pea lectin in Escherichia coli. The plasmid coding for the lectin was constructed from two lectin cDNA sequences isolated from Pisum sativum seeds (Higgins, T. J. V., Chandler, P. M., Zurawski, G., Button, S. C., and Spencer, D. (1983) J. Biol. Chem. 258, 9544-9549) and an expression vector based on the gene for the outer membrane lipoprotein of E. coli (Nakamura, K., and Inouye, M. (1982) EMBO J. 1, 771-775). The lectin is produced as a single polypeptide chain and forms insoluble aggregates in E. coli cells (2-5 mg/liter). Functional lectin is recovered by solubilization of the aggregates in guanidinium hydrochloride, renaturation in the presence of MnCl2 and CaCl2, and affinity purification on Sephadex. This procedure yields a homogeneous 28,000-dalton protein. Comparison of the recombinant lectin with natural pea lectin in an inhibition of hemagglutination assay demonstrated that there is no detectable difference in the carbohydrate binding properties of the two lectins.

The application of functional magnetic resonance (MR) imaging techniques to the measurement of oxygenation and blood flow in tumors is described. Gradient recalled echo MR imaging (GRE-MRI) offers a real-time noninvasive method for monitoring tumor response to vasomodulators such as carbogen (95% O"2/5% CO"2) breathing in attempts to overcome tumor hypoxia and improve treatment efficacy. Although the response is tumor-type dependent, increases in signal intensity of up to 100% have been observed in several animal tumor types. Responses are also seen in human tumors. The observed increases in GRE-MRI signal intensity are due to a combination of a reduction of deoxyhemoglobin in the blood causing changes in the MR imaging relaxation time T"2^* and changes in blood flow and may also reflect the capillary density. Thus, the magnitude of the GRE image intensity change gives an indication of the potential response of an individual tumor to treatments that aim to improve tissue oxygenation and therefore how the tumor may respond to therapy. In addition, carbogen breathing by the host has been shown to increase the uptake and efficacy of chemotherapeutic agents in animal tumors.

The 2.6-A x-ray crystal structure of bovine alpha-thrombin in complex with rhodniin, a protein inhibitor isolated from the bug Rhodnius prolixus, has been solved and refined. The structure has enabled us to trace the N-terminal part of the 49-residue A-chain of bovine alpha-thrombin for the first time, which is fixed in a U-shaped loop on the molecular surface opposite the active site canyon. Model building shows that the 25 amino acid residues that link the A-chain and F2 kringle cannot run through the fibrinogen recognition exosite. This demonstrates that this fibrinogen recognition exosite is available in prothrombin and meizothrombin.

The article discusses the improvements in stucco-based exterior insulation finish systems (EIFS) in the U.S. Buck Buchanan of Sto Corp. defines the growth of EIFS as occurring in two phases, namely energy conservation and Postmodernism. The Exterior Insulation Manufacturers Association (EIMA) promotes EIFS and works to ensure the model code agencies that theirs are safe, viable products.

The article focuses on the architectural design of the Knott Athletic Recreation/Convocation Complex at a campus in rural Maryland, which incorporates the tension-structured fabric roof designed by Horst Berger Partners. It states that the athletic complex offers space for varsity and intramural sports of the 1,800 students and entices community participation by providing shared spaces. It cites that the double-layered roof consists of a silicone-coated fiberglass and an ethylene propylene diene monomer (EPDM) fabric liner, for thermal insulation.

The article discusses developments in the 1980s architectural practice. It is stated that in the past decades, greater public awareness of architecture, both in positive and negative aspects has been brought in the country. Following the interest of people in architecture is the developing abilities of architecture clients. Clients' knowledge on design challenge architects to improve their ability.

The article offers information on Griggs Farm, a 280-unit affordable housing project in Princeton, New Jersey. Half of the units are offered at below market rates for low and moderate-income buyers and renters as a compliance to the Mount Laurel decision in 1975. It carries the name of its owner Burnett Griggs, who appealed to the court to save the area from commercial development. However, the property was sold to the Princeton Community Housing (PCH).

The article focuses on the architectural education of the Virginia Polytechnic Institute and State University in Blacksburg, Virginia. It discusses the obsolescence of the department of architecture due to the incorporation of the educational philosophy on the teaching of a small number of students. The Bachelor of Architecture program comprises foundation of studies, professional studies, undergraduate thesis work and off-campus study.

The article offers information on Rowan Williams Davies & Irwin Inc. (RWDI), a Canadian consulting engineering firm specializing in microclimate studies. The company's microclimate laboratory in Guelph, Ontario was introduced in 1972 to conduct studies on the effects of wind, snow, airborne pollutants, and the sun. According to RWDI President William H. D. Rowan, the designers' increased interest in air quality has boosted his firm's business.

The article presents information on several larger-scale commercial buildings that were pioneers in the use of energy-conservation techniques in the U.S. The Lovins House at the Rocky Mountain Institute Research Center in Old Snowmass, Colorado uses air-to-air heat exchangers, air locks for exterior doors, and efficient fluorescent lamps. Meanwhile, the Mississippi County Community College in Blytheville, Arkansas employs photovoltaics (PV) as a source of electrical energy for its new building complex.

The article presents the results of interviews with representatives of seven architectural firms on the commingling of the art and science of design into the reality of architecture. According to Robert J. Frasca of Zimmer Gunsul Frasca Partnership, architects need to recognize that architecture goes beyond just the execution of design. William H. Grover of Centerbrook Architects reveals that the firm has no formal review process among the partners.

The article discusses restorations made to the Octagon House in Washington, D.C. American Institute of Architects (AIA) first conducted repairs to the building to ensure its suitability for office use from 1902 to 1926. Some of the restorations made during the postwar period were the repair of the stairway at the second floor, replacement of floor and recast of cornices and ceiling. The Fellow American Institute of Architects made renovations in the building's basement rooms and fireplaces in 1968.

The article focuses on the restoration of the Union Station in Washington, D.C. The Congress authorized the Department of the Interior to spend $11 million to conduct structural repairs and install a new roof. The Congress has also established Union Station Redevelopment Corp. (USRC) to oversee the restoration and hired Harry Weese & Associates and Gilbane Building Co. as construction manager. Union Station Venture Ltd. (USVL) was selected for the development aspect of the project while Dick Corp. is the contractor.

The article focuses on the architectural acoustics of the technical building at the Skywalker Ranch production facility owned by film director George Lucas in Marin County, California. It says that the technical building is a facility for postproduction sound recording and mixing which has sound stages and mixing rooms. It states that Backen, Arrigoni & Ross Inc. and Charles M. Salter Associates faced a series of challenges in the acoustic requirements for the recording spaces and isolated site.

The article presents several factors to consider when selecting windows and skylights in relation to a series of case studies. They include structural factors which include wind load and operating forces. The architects of the Wroxton Street Town Houses by William F. Stern & Associates strove for interior windows and cameo views to the outside.

An interview with several experts on the role of computer programmers in architecture is presented. David M. Harper of Harper Careño in Miami believes that changes in design approach have assimilated programmers into the design process. Herbert McLaughlin of Kaplan/McLaughlin/Diaz thinks that postmodernism in architecture has made programming a distinct art form. Wilbur H. Tusler Jr. of Stone Marraccini & Patterson opines that programming process of the 1960s and 1970s has been bypassed in the 1980s movement for search of a new product.

The article discusses methods for testing the life span of single-ply roofing. Basic accelerated tests used by manufacturers are the QUV test, carbon-arc testing, xenon-arc testing and the equitorial mount with mirrors for acceleration with water test. According to the article, roof warranty is the indication of roofing system reliability most visible to the owner.

The article focuses on the role of the project team involved in the architectural design and construction of the Liberty Center building in Pittsburgh, Pennsylvania. The design involved a combination of prefabricated and traditional structural systems which accommodates the project's mixed uses. Component delivery was the construction management challenge posed by the modular system.

The article focuses on the issue regarding the laws relating to the construction of buildings in the U.S. It outlines the major concerns in response to building fire disasters including fire resistance. According to the author, the building codes of today do not seem to be the target of the complaints but rather the situation of architects working in more than one jurisdiction. She explains that microcomputers will likely influence the future relationship of designers to building codes.

Information about several papers discussed at the International Council for Building Research, Studies and Documentation (CIB) held in Washington, D.C. in September 1987 is presented. The papers presented include "Modern Trends in Rural Housing," "Prospects and Strategies for Local Building Materials Development in Africa" and "Properties of Lightweight Aggregate Concrete Made with Ethiopian Pumice and Scoria."

The article presents views from nine architectural educators on the integration of technical education into the design studio. It also offers some alternative approaches toward accomplishing the technical education of architects. It also features several schools of architecture that offer technology course tied to architectural studios.

The article examines the architectural design of the National Commercial Bank, as applied by Skidmore, Owings & Merrill architects. To break the tradition with the Saudi Arabian practice of spread-out and horizontal architecture, these architects have decided to sit the bank on an irregular shaped and placed it between the old city and the sea. It likewise has been characterized by a central wall to allegedly allow accumulated heat to rise out of the courts.

The article reports on the technological advances utilized in various establishments to ensure safety from any form of calamities. Fire stops and barriers have become prevalent in most buildings due to the occurrence of big fires which damaged properties and produced numerous casualties. Likewise, fire suppression systems were also developed for special building situations. Moreover, homebuilders also formulated solar technologies which include motorized and automated controls.

The article discusses the role of architect professionals in the approval of shop drawings in the U.S. Shop drawings, by nature more detailed than drawings in the contract documents, serve several purposes. Overall, they explain how the contractor intends to construct a portion of the work. Specifically, shop drawings indicate a component of the work.

The article examines appropriate wood connections with emphasis on wood shrinkage and swelling. It notes that excellent anticipation on the mode of shrinkage allows one to locate connections which could help deal about extra stress. It likewise adds that shrinkage, which results from the significant loss of moisture content, must likewise be considered in the connection of wood to other materials. Meanwhile, it provides illustrations that sample problems related to shrinkage.

The article provides information on the solutions to problems related to building rehabilitation in the U.S. It is stated that building rehabilitation involves assessing structural soundness, reconfiguring interior space to meet the needs and upgrading mechanical and electrical systems. It has been noted that access for people with disabilities is another concern with respect to historic rehabilitation projects.

Analysis of duration of hospitalization of patients admitted to the Texas Institute for Rehabilitation and Research during the past 10 years has provided guidelines for testing the efficiency of the rehabilitation process. This study was conducted in order to provide meaningful criteria of optimal length of stay in rehabilitation centers. Analyses of variance and regression analyses were made on rational subgroups of patients using data stored in the computer files on nature of disability, program of hospitalization, attending physician, and year of discharge. Control charts and statistical tables were provided for internal management of the Institute as well as for use by other agencies. The analyses revealed varying length of stay among disabilities; marked differences in hospital duration among care programs; no significant variation of the patient's length of stay among patient groups classified according to attending physician, and yearly deviation of duration of hospitalization within the established control limits but no evidence of a downward trend.