bluuebunny/crossref_metadata_2025 huggingface dataset:
Sketches of American mayors. III. James M. Curley of Boston
Authors: Goos T. G.
Published: June 2007

From early years an indefatigable political worker, Curley rose from the tenements to become twice mayor of Boston. Self dramatization is his strength and as old friends leave him a new following springs up. And Boston hasn't finished with him yet, nor he with Boston.
Crime and political corruption in Chicago. Facts versus melodrama
Authors: Yarros Victor S.
Published: June 2007

The recent flurry in Washington advertised Chicago as the National crime center. Is tte reputation deserved? Are their peculiar forces at work there? Is the Volstead Act responsible?
Is there a vicious circle of transit development and city congestion?
Authors: Turner Daniel L.
Published: June 2007

Shall we ever catch up in rapid transit construction? No, unless we build decentralizing lines or limit building operations and the extent to which land can be used.
Local government in Ireland under the free state
Authors: Horgan John J.
Published: June 2007

Mr. Horgan is a solicitor, residing in Cork, who has held numerous local ofices and has written widely on legal and political topics. You will find his article both scholarly and captivating.
Baltimore's new retirement system
Authors: Buck George B.
Published: June 2007

Baltimore substitutes a sound municipal pension system for various depadmental and piecemeal plans.
The bicameral principle in the new mexico legislature
Authors: Hall John E.
Published: June 2007

The possibilities latent in the bicameral system when one party dominates the senate and the other the house. The results justify the National Municipal League's proposal contained in our Model State Constitution for a single–chamber legislature.
Standards of adequate fire protection
Authors: Booth George W.
Published: June 2007

Measurements such as any citizen amy apply to the fire–fighting forces of his own city.
The skyschaper does cause congestion. Major Curran comes back at Mr. Corbett
Authors: Curran Henry H.
Published: June 2007

A reply to harvey Wiley Corbett's article, “Up Wtih hte Skyscraper,” in the February Review.
The case method of instruction in municipal government
Authors: Munro William B.
Published: June 2007

The case method applied ot college courses in municipal government with some hints as to how to proceed.
The Lessons of the Colorado River Compact
Authors: Corwin Edward S.
Published: June 2007

Will interstate compacts concluded under the campact clause of the United States Constitution provide the politicla authority needful to control the interests of large regions?
Chicago's disposition of street traffic violations
Authors: Hulse Granvyl G.
Published: June 2007

As a class, the most serious cases receive the most inefficient treatment. The traffic bureau with system of automatic fines proves its worth
Compulsory atuomobile insurance. Compensation, not liability insurance needed
Authors: Marx Robert S.
Published: June 2007

Compel every automobile owner to procure a compensation insurance policy as a condition to obtaining a drivre's license, victims of accidents to be compensated from the insurance fund according to fixed schedules and without regard to fault
Women as lobbyists
Authors: Boyce William A.
Published: June 2007

If you want your bill passed by the legislature, writes Mr. Boyce, enlist the services of one or more attractive, keen–witted and resourceful women to lobby it through
Putting the citizens to work for government
Authors: Stone Hubert W.
Published: June 2007

Town officials of Harrison, N. Y., receive expert advice nad assistance in budgetin and other administrative problems from a non–official group of citizens called the Finance Committee
Zoning in minnesota; eminent domain vs. police power
Authors: Anderson William
Published: June 2007

The development of zoning law in Minnesota is a cross section of the history of zoning in the United States
The initiative and the referendum in 1925 and 1926
Authors: Boots Ralph S.
Published: June 2007

A review of the use and the results of I. and R. in 1925 and 1926, with tables of votes on measures
Free cities in oklahoma
Authors: Barth Harry
Published: June 2007

Oklahoma gives its cities greater greedom of local self–government than do most other states. State control is limited to education, pubilc utility rates, tax limits, and methods of removing city officials
American governors
Authors: Macdonald Austin F.
Published: June 2007

The governorship may sometimes be a stepping–stone to fame; usually it is a tobaggan ot political oblivion. Greater emphasis on the administrative functionof hte governor is needed
Des Moines Tries The Conciliation Court
Authors: Aumann Francis R.
Published: June 2007

Des Moines joins the list of cities which have lifted justice in small matters out of the class of probihited luxuries available only to the rich.
Dublin's Proposed manager‐council plan
Authors: Boland F. H.
Published: June 2007

The Free State is about to confer city manager government upon Greater Dublin. The proposal departs from the American plan inseveral important features designed to meet conditions peculiar to Ireland. The system of metropolitan government is novel.
Voteless Washington expresses itself
Authors: Havenner George C.
Published: June 2007

The effective work of spotaneous voters' associations in a district in which no one can vote, told by the President of the Anacostia Citizens' Association, an officer of the Federation fo Citizens'; Associations, and a farmer member of the Citizens' Advisory Council.
The french parliamentary elcetions and the new electoral law
Authors: Pollock James K.
Published: June 2007

France ha restored the single member system with the second ballot for Parliamentary elections, after two experiences with a bogus form of proportional representation.
Depreciation in commercial and municipal accounting
Authors: Landman Adrian M.
Published: June 2007

Many municipalities operating under laws requiring the retirement of indebtedness have a sounder financial structure than large nmbers of commercial companies which meticulously set up theoretical depreciation.
Philadelphia's free library
Authors: Woodruff Clinton Rogers
Published: June 2007

Philadelphia's new library results in increased use by the reading public.
The tax situation in chicago
Authors: Simpson Herbert D.
Published: June 2007

The second of three articles describing the inequalities of the present assessement methods in Chicago.
The Virginia reorganization program
Authors: Tucker Robert H.
Published: June 2007

A concise and interesting appraisal of Governor Byrd's reorganization program, by a member of the commission on simplification and economy of 1922‐24, and of the special citizens' committee of 1927.
Report on work of the National municipal league. For the year ending October 1, 1928
Authors: Forbes Russell
Published: June 2007

This report shows a steady growth in the League's work and accomplishment.
Compatative tax rates of 237 cities, 1928
Authors: Rightor C. E.
Published: June 2007

Mr. Rightor's annual compilation, which speaks for itself.
Wanted: A measuring stick for school systems
Authors: Gulick Lutber
Published: June 2007

Current methods of measuring schOOl performance do not really measure.
What P. R. has done for Cincinnati
Authors: Bentley Henry
Published: June 2007

Heralded as the friend of minorities, P. R. has given majority representation to the real majority group in Cincinnati.
Our American mayors XI. Murray Seasongood of Cincinnati
Authors: Wilson Russell
Published: June 2007

A leader of the shock troops in the fight for the city manager charter, Mayor Seasongood has become chief of staff. He is the ideal mayor in a city manager form of government.
Order for chaos in traffic signals
Authors: Powell William B.
Published: June 2007

The American Engineering Council Committee reports a standard pratice for traffic control.
Police court justice in England
Authors: Harley Herbert
Published: June 2007

Mr. Harley's article should be read in connection with Mr. Manning's “In‐justices of the Peace,” appearing in this issue.
Politics in New York city schools
Authors: Marsh H. W.
Published: June 2007

Since the days of Mayor Hylan politics has dominated the filling of the higher posts in New York Ciiy's public schools. Persistent efforts at reform have been frustrated.
Taxation in the proposed metropolitan government of Pittsburgh
Authors: Reed Thomas H.
Published: June 2007

Designing a new government for a metropolitan area raises fresh problems of taxation which, however, were sidestepped by the Pennsylvania legislature which permitted no change in the present system of assessment and taxation in Pittsburgh. With respect to these powers the metropolitan city of Pittsburgh is merely the successor of Allgheny Counly.
The Los Angeles municipal exhibit
Authors: Knox Roy A.
Published: June 2007

How the city's functions were pictured
Glasgow the practical
Authors: James Harlean
Published: June 2007

No American city approaches Glasgow in the number and range of municipal activities.
Consolidation of New York city hospitals
Authors: MCCombs Carl E.
Published: June 2007

The recent consolidation of three departments under a single commissioner is regarded by New York City's leaders in public health and welfare work as a long step toward more efficient care of the sick and more economical use of public funds.
St. Paul cleans up its welfare administration
Authors: Lefkovitz Herbert
Published: June 2007

After graft disclosures resulting in prison sentence of one official and the unexplained death of another, St. Paul decides to abandon the antiquated board of control, in charge Since 1872 of control, in charge since 1872 of the joint welfare activities of the city and county.
Voters turn thumbs down on Pittsburgh's metropolitan charter
Authors: Faust Martin L.
Published: June 2007

Although a majority of the voters of Allegheny County approved the charter after emasculation by the state legislature, it did not receive the necessary two‐thirds vote in a majority of the municipal units.
Movies socialized for town's benefit
Authors: Bayard C. C.
Published: June 2007

Hanover, New Hampshire, builds sidewalks, maintains shade trees, buys fire apparatus from profits of a motion picture monopoly.
Municipal government in soviet russia iii. municipal finance
Authors: Maxwell Bertram W.
Published: June 2007

This is the third and last of a series of article on the government o Russian cities, the previous articles having appeared in the December adn January issues of the REVIEW
Water power in new york state
Authors: Blair Knapp A.
Published: June 2007

Electric power is rapidly becoming the dominant force in our industrial civilization. Its importance in the factory and home in the city and in the country daily becomes greater adn greater. An important though admittedly not the most important portionof future power development valuable water power in its St. Lawrence and Niagara Rivers adn its inland streams

Despite the extent of this untapped wealth New York did not evolve a power policy until 1921. Even now it cannot be said to have settled upon a method of development adn exloitation

This is due to the fact that the two dominant paities hav been at logger heads with reference to this problem. Present indications point to a determination on the part o both to substitute action for words, and in such a situation a brief resume of hte fundamental positions of each may have some value. Space does not allow the description of the efforts of commissions prior to 1921. We lead you directly to the Water Power Act of 1921 which represents the Republican position, and which has been teh policy adopted by the legislature o he state, but which has been nullified by the attitude of Democratic commissions charged with its administration
Business administration: a weak spot in our ciyt schools
Authors: Smith Harry P.
Published: June 2007

Rsponsibility for city school administration is too often divided among coordinate heads, wiht the result that there is lack of correlation between the educational and the business phases of school operation
A message to city planners
Authors: Crane Jacob L.
Published: June 2007

Are we on he right track in city plannig?
The fight for reform in rockland county
Authors: Morse Perley
Published: June 2007

How one of those counties of New York which have made “less improvement in governmetnal matters than any other political aency” turned over a new leaf
Budget‐making in seven cities
Authors: Walker Mabel L.
Published: June 2007

The Author has made personal observation of budget practice in seven of our largestcities
A policeman's lot: An appraisal of grover whalen's tour de force as police commissioner of New York city
Authors: McGoldrick Joseph
Published: June 2007

Measured by column inches of publicity, Grover Whalen was a great success as police commissioner of New York.
Illinois legislature comes to aid of Chicago
Authors: Martin Edward M.
Published: June 2007

The Illinois legislature in special session has passed a series of bills to relieve the financial distress of Chicago and Cook County. Efforts to improve the assessment machinery failed but will be renewed when the legislature meets next year.
The city manager movement in St. Paul
Authors: Lefkovitz Herbert
Published: June 2007

St. Paul voters twice decide against manager charter within a period of eight months.
Gender and corruption: testing the new consensus
Authors: Alhassan‐Alolo Namawu
Published: June 2007

The search for a sustainable anti‐corruption strategy has seen a number of reform ideas introduced into the public sector of many African countries, by the development community. These reforms have met with modest results, at best, as evidenced by the fact that current data suggest entrenched corruption in many African countries. Failure of previous anti‐corruption strategies leads to the promotion of women in the public sector as a potential anti‐corruption remedy. This nascent idea is premised on presumptions that women are more ethical than men. However, failure of previous anti‐corruption strategies begs legitimate questions: would women prove less corrupt when exposed to environments characterised by corrupt opportunities and networks? Would women maintain high ethical standards in the public realm when social obligations require certain acts of corruption? This article uses primary data from Ghana to address these questions. The article concludes that women may not prove less corrupt in the public sector if corrupt opportunities and networks are not restrained. Also, the very gender system, which is used to justify women's proclivity to less corrupt behaviour and subsequent integration into the public sector, could itself be the source of corruption as women attempt to fulfil their gender roles. Copyright © 2007 John Wiley & Sons, Ltd.
Ethnic differences in determinants of participation and non‐participation in prenatal screening for Down syndrome: A theoretical framework
Authors: Fransen Mirjam P. , Essink‐Bot Marie‐Louise , Oenema Anke , Mackenbach Johan P. , Steegers Eric A. P. , Wildschut Hajo I. J.
Published: June 2007

Objective To develop a theoretical framework for analysing ethnic differences in determinants of participation and non‐participation in prenatal screening for Down syndrome.

Methods We applied Weinstein's Precaution Adoption Process (PAP) Model to the decision of whether or not to participate in prenatal screening for Down syndrome. The prenatal screening stage model was specified by reviewing the empirical literature and by data from seven focus group interviews with Dutch, Turkish and Surinamese pregnant women in the Netherlands.

Results We identified 11 empirical studies on ethnic differences in determinants of participation and non‐participation in prenatal screening for Down syndrome. The focus group interviews showed that almost all stages and determinants in the stage model were relevant in women's decision‐making process. However, there were ethnic variations in the relevance of determinants, such as beliefs about personal consequences of having a child with Down syndrome or cultural and religious norms.

Discussion The prenatal screening stage model can be applied as a framework to describe the decision‐making process of pregnant women from different ethnic backgrounds. It provides scope for developing culturally sensitive, tailored methods to guide pregnant women towards informed decision‐making on participation or non‐participation in prenatal screening for Down syndrome. Copyright © 2007 John Wiley & Sons, Ltd.
Ethenyl indoles as neutral hydrophobic fluorescence probes
Authors: Singh Anil K. , Hota Prasanta K.
Published: June 2007

3‐(4‐Nitrophenylethenyl‐E)‐NH‐indole (1), 3‐(4‐nitrophenyl ethenyl‐E)‐N‐acetylindole (2), and 3‐(4‐nitrophenylethenyl‐E)‐N‐benzenesulfonylindole (3) are relatively less fluorescent in organic solvents, with fluorescence quantum yield (Φf) in the range of 0.002 to 0.066 depending on the solvent polarity. However, in bovine serum albumin (BSA)‐phosphate buffer, the fluorescence of these compounds gets drastically enhanced with Φf in the range of 0.21 to 0.67, depending on the substituent on the indolic nitrogen atom. Additionally, linear increase in the fluorescence intensity of 2 and 3 occurs on increasing the BSA concentration. These fluorescence properties together with the neutral, hydrophobic nature of these compounds make these fluorophores good fluorescence probe for studying the micropolarity of proteins like BSA and in general the ligand–protein interactions. Copyright © 2007 John Wiley & Sons, Ltd.
Molecular dynamics study of polymer crystallization in the presence of a particle
Authors: Zhang Dongsheng , Meyer Hendrik
Published: June 2007

We have used molecular dynamics simulations with a coarse‐grained model to study the effect of a particle on the crystallization of polymer melt. We analyzed in particular a bond order parameter to characterize the nucleation and crystallization process. Our calculations show that the presence of a particle modifies the free energy landscape of polymer melts, locally induces the ordering of polymer melts near the particle surface, and thus enhances the polymer crystallization. Because the interaction between the particle and polymers is repulsive, our results suggest that the origin of the enhancement for polymer crystallization is entropic. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2161–2166, 2007
Pre‐analytical influence on the low molecular weight cerebrospinal fluid proteome
Authors: Berven Frode S. , Kroksveen Ann C. , Berle Magnus , Rajalahti Tarja , Flikka Kristian , Arneberg Reidar , Myhr Kjell‐Morten , Vedeler Christian , Kvalheim Olav M. , Ulvik Rune J.
Published: June 2007

Cerebrospinal fluid (CSF) is a perfect source to search for new biomarkers to improve early diagnosis of neurological diseases. Standardization of pre‐analytical handling of the sample is, however, important to obtain acceptable analytical quality. In the present study, MALDI‐TOF MS was used to examine the influence of pre‐analytical sample procedures on the low molecular weight (MW) CSF proteome. Different storage conditions like temperature and duration or the addition of as little as 0.2 µL blood/mL neat CSF caused significant changes in the mass spectra. The performance of different types of MW cut‐off spin cartridges from different suppliers used to enrich the low MW CSF proteome showed great variance in cut‐off accuracy, stability and reproducibility. The described analytical method achieved a polypeptide discriminating limit of approximately 800 pM, two to three orders of magnitude lower than reported for plasma. Based on this study, we recommend that CSF is centrifuged immediately after sampling, prior to storage at –80ºC without addition of protease inhibitors. Guanidinium hydrochloride is preferred to break protein‐protein interactions. A spin cartridge with cut‐off limit above the intended analytical mass range is recommended. Our study contributes to the important task of developing standardized pre‐analytical protocols for the proteomic study of CSF.
Simulated annealing exploration of an active‐site tyrosine in TEM‐1β‐lactamase suggests the existence of alternate conformations
Authors: Doucet Nicolas , Pelletier Joelle N.
Published: June 2007

TEM‐1 is a class A β‐lactamase that contributes to the primary defensive measure used by bacteria to hydrolyze the clinically‐relevant β‐lactam antibiotics. Several crystal structures of this enzyme complexed with inhibitors display the active‐site residue Tyr105 in an alternate orientation relative to that assigned in the free or in the substrate‐bound forms. Thus, the alternate conformation may not be favored in the free enzyme and may be adopted only in the presence of inhibitor. As the residue at position 105 is a determinant of substrate specificity, we sought a better understanding of the relation between its conformation and its function in ligand binding. Here, we perform a molecular dynamics simulated annealing protocol to identify stable orientations adopted by Tyr105 in free TEM‐1. Our results demonstrate that, in the absence of substrate, structurally validated conformers of Tyr105 predominantly adopt either of the two rotameric orientations observed in the crystal structures. This suggests that adoption of either conformation in the free enzyme is energetically favored and is not strictly promoted by ligand binding. We propose that free TEM‐1 alternates between these two conformations of Tyr105 and that a dynamically heterogeneous population of both rotamers exists in solution. The conformational change significantly reshapes the active‐site cavity and modifies the potential for forming specific ligand contacts. Our results add to the body of evidence suggesting that Tyr105 displays a dynamical behavior resulting in alternate ligand binding modes and are consistent with the lower affinity of TEM‐1 for cephalosporins relative to penicillins. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Electronic activity of SiC precipitates in multicrystalline solar silicon
Authors: Bauer Jan , Breitenstein Otwin , Rakotoniaina Jean‐Patrice
Published: June 2007

In the upper part of block‐cast multicrystalline silicon one often finds silicon carbide and silicon nitride precipitates and inclusions. These contaminants can cause severe ohmic shunts in solar cells and thus decrease the efficiency of the solar cells very strongly. It is well known that the silicon carbide precipitates cause the ohmic shunts. However, the electrical properties of the silicon carbide was unknown so far. To study the electrical properties of these silicon carbide particles we isolated them from the silicon bulk material and performed different electrical measurements on them. The measurements show that the silicon carbide precipitates are highly conductive. An investigation of the heterojunction silicon–silicon carbide was also performed and a simulation of this heterojunction leads to a new model of the ohmic shunt mechanism. It is concluded that the shunt current flows inside of the filaments. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High‐stress plasticity and the core structures of dislocations in silicon
Authors: Rabier J.
Published: June 2007

The recent observation of perfect dislocations at high stress and low temperature in silicon [J. Rabier, P. Cordier, J. L. Demenet, and H. Garem, Mater. Sci. Eng. A 309/310, 74 (2001)] in accordance with the calculations of Duesbery and Joos [M. S. Duesbery and B. Joos, Philos. Mag. A 74, 253 (1996)] has solved the apparent paradox regarding the nature of mobile dislocations in silicon under usual deformation conditions. However, although several experiments and calculations are consistent with those perfect dislocations being located in the shuffle set, little is known about the actual core structure of those dislocations which lie along unusual Peierls valleys: 〈112〉/30°, 〈123〉/41°. This paper aims to review and discuss recent results related to high‐stress plasticity and dislocation core structure in silicon. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Iberian thermal lows in a changed climate
Authors: Hoinka Klaus P. , Gaertner Miguel , de Castro Manuel
Published: June 2007

Recent results from enhanced greenhouse‐gas scenarios over southern Europe suggest that climate change implies a summertime mean surface warming of up to 4 K over the Iberian Peninsula. It is suggested that thermal lows, the most prominent Iberian summer weather, will undergo significant modifications in a changed climate. This is studied in the present paper by determining statistical features of the Iberian thermal low, at first for today's climate using data provided by ERA‐40 and by the regional climate model PROMES. In general the analysed and simulated climatic structures compare well. However, the ERA‐40 data provide conditions more favourable for thermal lows than simulated with the model. Statistics in a changed climate are obtained by performing two 30‐year model simulations for 1961–1990 and 2071–2100. It is found that thermal lows strengthen by decreasing the central Iberian surface pressure from 1012.2 to 1010.5 hPa and increasing its daily variation by about 7% in magnitude. Associated with this is an increase in the number of thermal low days by more than 60%. A second finding is an enhancement of the sea breezes over the Iberian westerly and easterly coasts and a particularly significant strengthening of the sea breeze between Cadiz and Huelva. The westerly flow over the Strait of Gibraltar, observed during thermal low events, decreases. The increase in occurrence of the thermal low is associated with a significant increase in the number of dry spells of longer period, and could involve considerable impact on desertification, water resources and wildfire hazards around the Mediterranean basin. The results suggest that there is some evidence that the subtropical character of the Mediterranean climate strengthens. Copyright © 2007 Royal Meteorological Society
Characterization and determination of six aristolochic acids and three aristololactams in medicinal plants and their preparations by high‐performance liquid chromatography‐photodiode array detection/electrospray ionization mass spectrometry
Authors: Yuan Jinbin , Liu Qian , Wei Guobing , Tang Fei , Ding Li , Yao Shouzhuo
Published: June 2007

Aristolochic acid derivatives (AAs) and aristolactam derivatives (ALs) have been characterized by electrospray ionization mass spectrometry, and their fragmentation pathways are proposed. ALs exhibit a single ionization product [M+H]+, whereas AAs show multiple ionization products. By optimizing the chromatographic separation and mass spectrometric parameters, the precursor ions of the derivatives with the best responses were found, and the sensitivities in the determination of the nine derivatives were improved. Based on the investigation of ionization behaviour, a HPLC‐DAD/ESI‐MS (high‐performance liquid chromatography‐photodiode array detection/electrospray ionization mass spectrometry) method has been developed for simultaneous analysis of nine derivatives, i.e., AA I, AA II, AA C, AA D, 7‐OH AA I, aristolic acid I, AL AII, AL IIIa and AL IVa, in nine medicinal herbs and two preparations. The method appears to be suitable for safety assurance and quality control of commercially available samples with good selectivity and suitable sensitivity. Copyright © 2007 John Wiley & Sons, Ltd.
Scanning and Transmission Electron Microscopy for Evaluation of Order/Disorder in Bone Structure
Authors: Suvorova Elena I. , Petrenko Pavel P. , Buffat Philippe A.
Published: June 2007

A comparative characterization of the structure of normal and abnormal (osteoporotic) human lumbar and thoracic vertebrae samples was carried out to reveal the type of possible disorder. Samples from the bone fragments extracted during the surgery due to vertebra fractures were examined by scanning electron microscopy (SEM), conventional and high resolution transmission electron microscopy (TEM and HRTEM), and X‐ray energy dispersive spectroscopy (EDS). Contrary to what might be expected in accordance with possible processes of dissolution, formation and remineralization of hard tissues, no changes in phase composition of mineral part, crystal sizes (length, width, and thickness), and arrangement of crystals on collagen fibers were detected in abnormal bones compared to the normal ones. The following sizes were determined by HRTEM for all bone samples: ≤ 20 nm in length, 3–15 nm in width, and 0.8 nm in thickness (the height of hexagonal HAP unit cell along the [2110] direction. Significant overgrowth of organic fibers filled up the former paths for blood vessels and nerves together with organic films covering the mineral part was revealed by SEM only in osteoporotic bones. EDS showed that this organic tissue was not mineralized. Penetration of such organic fibers inside bones can result in bone dilatation and lower the mineral density, deteriorating the mechanical properties and finally terminating in fracture.SCANNING 29: 000–000, 2007. © 2007 Wiley Periodicals, Inc.
The stoichiometry of the T cell antigen receptor and its implications for the signal transduction mechanism
Authors: Schamel Wolfgang W. A.
Published: June 2007

The T cell antigen receptor (TCR·CD3) is a multi‐subunit complex mediating T cell development and activation. The molecular mechanism of how this receptor transmits information across the membrane is still an enigma. The stoichiometry and architecture of this receptor in the membrane are under intense investigation, since they are important in deciphering the signal transduction mechanism of the TCR·CD3. This review highlights the evidence that TCR·CD3 is found on unstimulated T cells in monovalent (one ligand‐binding site per receptor) as well as in multivalent forms. Distinct detergents affect the integrity of the multivalent receptor differently, explaining controversial findings of TCR·CD3 stoichiometries as determined by biochemical means. The existence of multivalent receptors is not compatible with current models of TCR·CD3 triggering. Therefore, I discuss the novel “permissive geometry model” that combines multivalent TCR·CD3s, the requirement for multimeric ligands for receptor triggering and conformational changes at CD3.
Caspase Inhibitor Z-VAD-FMK Enhances the Freeze-Thaw Survival Rate of Human Embryonic Stem Cells
Authors: Heng Boon Chin , Clement Marie Veronique , Cao Tong
Published: June 2007

Previous study demonstrated that the low survival of human embryonic stem cells (hESC) under conventional slow-cooling cryopreservation protocols is predominantly due to apoptosis rather than cellular necrosis. Hence, this study investigated whether a synthetic broad-spectrum irreversible inhibitor of caspase enzymes, Z-VAD-FMK can be used to enhance the post-thaw survival rate of hESC. About 100 mM Z-VAD-FMK was supplemented into either the freezing solution, the post-thaw culture media or both. Intact and adherent hESC colonies were cryopreserved so as to enable subsequent quantitation of the post-thaw cell survival rate through the MTT assay, which can only be performed with adherent cells. Exposure to 100 mM Z-VAD-FMK in the freezing solution alone did not significantly enhance the post-thaw survival rate (10.2% vs. 9.9%, p > 0.05). However, when 100 mM Z-VAD-FMK was added to the post-thaw culture media, there was a significant enhancement in the survival rate from 9.9% to 14.4% (p < 0.05), which was further increased to 18.7% when Z-VAD-FMK was also added to the freezing solution as well (p < 0.01). Spontaneous differentiation of hESC after cryopreservation was assessed by morphological observations under bright-field microscopy, and by immunocytochemical staining for the pluripotency markers SSEA-3 and TRA-1-81. The results demonstrated that exposure to Z-VAD-FMK did not significantly enhance the spontaneous differentiation of hESC within post-thaw culture.
Efficient Synthesis of α‐Monoglycerides via Solventless Condensation of Fatty Acids with Glycerol Carbonate
Authors: Ghandi Mehdi , Mostashari Abdoljalil , Karegar Mojgan , Barzegar Mina
Published: June 2007

Highly pure α‐monoglycerides (5a–e) were successfully prepared in high yields by the condensation of fatty acids such as lauric, myristic, palmitic, stearic and oleic (2a–e) with glycerol carbonate (4‐hydroxymethyl‐1,3‐dioxolan‐2‐one) (1) in the presence of triethylamine as catalyst. Reaction conditions and spectroscopic identification of products will be presented in this article.
Regulation of various proteolytic pathways by insulin and amino acids in human fibroblasts
Authors: Esteban Inmaculada , Aguado Carmen , Sánchez Maribel , Knecht Erwin
Published: June 2007

Intracellular protein degradation is a regulated process with several proteolytic pathways. Although regulation of macroautophagy has been investigated in some detail in hepatocytes and in few other cells, less is known on this regulation in other cells and proteolytic pathways. We show that in human fibroblasts insulin and amino acids reduce protein degradation by different signalling pathways and that this inhibition proceeds in part via the mammalian target of rapamycin, especially with amino acids, which probably increase lysosomal pH. Moreover, the regulatory amino acids (Phe, Arg, Met, Tyr, Trp and Cys) are partially different from other cells. Finally, and in addition to macroautophagy, insulin and amino acids modify, to different extents and sometimes in opposite directions, the activities of other proteolytic pathways.
Metabolic stress in insulin's target cells leads to ROS accumulation – A hypothetical common pathway causing insulin resistance
Authors: Eriksson Jan W.
Published: June 2007

The metabolic syndrome is a cluster of cardiovascular risk factors, and visceral adiposity is a central component that is also strongly associated with insulin resistance. Both visceral obesity and insulin resistance are important risk factors for the development of type 2 diabetes. It is likely that adipose tissue, particularly in the intra‐abdominal depot, is part of a complex interplay involving several tissues and that dysregulated hormonal, metabolic and neural signalling within and between organs can trigger development of metabolic disease. One attractive hypothesis is that many factors leading to insulin resistance are mediated via the generation of abnormal amounts of reactive oxygen species (ROS). There is much evidence supporting that detrimental effects of glucose, fatty acids, hormones and cytokines leading to insulin resistance can be exerted via such a common pathway. This review paper mainly focuses on metabolic and other ‘stress’ factors that affect insulin's target cells, in particular adipocytes, and it will highlight oxidative stress as a potential unifying mechanism by which these stress factors promote insulin resistance and the development and progression of type 2 diabetes.
Thermodynamic determination of the binding constants of angiotensin‐converting enzyme inhibitors by a displacement method
Authors: Andújar-Sánchez Montserrat , Jara-Pérez Vicente , Cámara-Artigas Ana
Published: June 2007

Somatic angiotensin I‐converting enzyme (s‐ACE) plays a central role in blood pressure regulation and has been the target of most antihypertensive drugs. A displacement isothermal titration calorimetry method has been used to accurately determine the binding constant of three strong s‐ACE inhibitors. Under the experimental conditions studied in this work, the relative potency of the inhibitors was determined to be enalaprilat > lisinopril > captopril. We analyze the thermodynamic behaviour of the binding process using the new structural information provided by the ACE structures, as well as the conformational changes that occur upon binding.
Nonlinear magnetoacoustic waves in a cold plasma
Authors: ROWLANDS G. , ALLEN M. A.
Published: June 2007

The equations describing planar magnetoacoustic waves of permanent form in a cold plasma are rewritten so as to highlight the presence of a naturally small parameter equal to the ratio of the electron and ion masses. If the magnetic field is not nearly perpendicular to the direction of wave propagation, this allows us to use a multiple-scale expansion to demonstrate the existence and nature of nonlinear wave solutions. Such solutions are found to have a rapid oscillation of constant amplitude superimposed on the underlying large-scale variation. The approximate equations for the large-scale variation are obtained by making an adiabatic approximation and in one limit, new explicit solitary pulse solutions are found. In the case of a perpendicular magnetic field, conditions for the existence of solitary pulses are derived. Our results are consistent with earlier studies which were restricted to waves having a velocity close to that of long-wavelength linear magnetoacoustic waves.
Enhanced high‐altitude polar cap plasma and magnetic field values in response to the interplanetary magnetic cloud that caused the great storm of 31 March 2001: A case study for a new magnetospheric index
Authors: Osherovich Vladimir A. , Benson Robert F. , Fainberg Joseph , Green James L. , Garcia Leonard , Boardsen Scott , Tsyganenko Nikolai , Reinisch Bodo W.
Published: June 2007

The magnetospheric electron number density and the magnetic field strength near 8 RE over the polar cap increased dramatically after the arrival of an interplanetary magnetic cloud on 31 March 2001. These parameters were determined with high accuracy from the plasma resonances stimulated by the Radio Plasma Imager (RPI) on Imager for Magnetopause‐to‐Aurora Global Exploration (IMAGE) near apogee during both quiet (30 March 2001) and disturbed (31 March 2001) days. The quiet day and disturbed day values were each compared with magnetospheric magnetic field and electron density models; good agreement was found with the former but not the latter. The magnetospheric response was also expressed in terms of the ratio of the electron plasma frequency fpe to the electron cyclotron frequency fce, which is proportional to the ratio of the electron gyroradius to the Debye radius. Simultaneous Wind measurements of the solar wind magnetic field strength, speed, and plasma density were used to calculate the solar wind quasi‐invariant QI. This index is equivalent to the ratio of the solar wind magnetic pressure to the solar wind ram pressure or to the inverse of the magnetic Mach number squared. These nondimensional quantities, QI and fpe/fce, have fundamental meanings in the solar wind MHD regime and in the relation between electric and magnetic forces on electrons in the magnetosphere, respectively. During the large 31 March 2001 storm, IMAGE was at the right place at the right time so as to enable comparisons between RPI fpe/fce and Wind QI determinations. Both QI and fpe/fce formed maxima during 6‐hour observing intervals during this storm that were found to be highly correlated (87%) with a magnetospheric time lag of about 3 hours for fpe/fce. These results, based on a detailed case study of this important event, suggest that the plasma parameter fpe/fce may serve as a useful magnetospheric index.
Auroral NO+ 4.3 μm emission observed from the Midcourse Space Experiment: Multiplatform observations of 9 February 1997
Authors: O'Neil R. R. , Winick J. R. , Picard R. H. , Kendra M.
Published: June 2007

The Spatial Infrared Imaging Telescope III (SPIRIT III) radiometer on the Midcourse Space Experiment satellite (MSX), observed enhanced 4.3 μm emission from a very well characterized aurora over the Barents Sea on 9 February 1997, in conjunction with observations by the POLAR and FAST satellites, the Loparskaya ground site, and ultraviolet and visible spectrometers aboard MSX. Measurements of the auroral location, form, spatial extent and dosing conditions were applied to specify the component of auroral 4.3 μm radiance due to the slowly produced and optically thick CO2ν3 (001‐000) transition. An analysis based on the Auroral Atmospheric Radiance Code (AARC) indicates: (1) the emission originates near and beyond the tangent point; (2) the optically thick CO2ν3 radiation is largely self absorbed by the intervening atmosphere; and (3) the auroral enhancement is predominantly due to NO+ Δv = 1 vibrational state transitions. In addition, the analysis indicates that the previously reported laboratory result for the NO+ v ≥ 1 vibrational yield from the reaction, N+ + O2, is insufficient to account for the observed 4.3 μm emission. In order to explain the current results, we propose that there is additional production from the reaction, N2+ + O, forming NO+ in vibrational levels 0, 1, and 2 with relative populations of approximately 0.25, 0.5, and 0.25, respectively. The combined production processes yield an energetic electron induced efficiency of 0.56 ± 0.18 photons per auroral ion pair for NO+ Δv = 1 emission at altitudes equal to or greater than 112 km.
Coseismic deformation of the 2002 Denali fault earthquake: Contributions from synthetic aperture radar range offsets
Authors: Elliott Julie L. , Freymueller Jeffrey T. , Rabus Bernhard
Published: June 2007

We investigate coseismic deformation from the 2002 Denali fault earthquake using synthetic aperture radar (SAR) range offsets. Through a cross‐correlation technique, we form a range offset map from two radar amplitude images. A profile across the fault at the Trans‐Alaska Pipeline shows right‐lateral strike‐slip and displacement values that agree with predictions from a GPS‐based slip model to within the uncertainty of the range offset data. Using a fixed strike‐slip/dip‐slip ratio taken from geologic measurements, we derive a lateral slip estimate from the range offsets. This slip estimate shows that the largest geologic offset measurement in a region most accurately represents the full slip value. We then invert a combination of the range offsets, GPS data, and geologic surface offset data to solve for the slip distribution on a three‐dimensional fault model in an elastic half‐space. The combined model displays highly variable slip, with values generally increasing from west to east along the Denali fault, as well as four major patches of high slip on that fault. As expected, the combined model is nearly identical to the GPS‐based model outside the SAR coverage area. Within the coverage area, however, the combined model has better constraints and predicts slip values much closer to the geologic measurements. The offset map displays asymmetrical displacements across the fault. We show that a combination of a bending fault, variable slip, and the SAR line‐of‐sight geometry can explain this asymmetry. We also discuss how fault geometry influences slip and moment release along the rupture.
How can rainfall‐runoff models handle intercatchment groundwater flows? Theoretical study based on 1040 French catchments
Authors: Le Moine Nicolas , Andréassian Vazken , Perrin Charles , Michel Claude
Published: June 2007

This paper examines the possible solutions that may allow a rainfall‐runoff model to cope with the existence of unknown intercatchment groundwater flows over a given catchment. On the basis of a large catchment set we compare four versions of the GR4J and the SMAR rainfall‐runoff models that differ in the way they use one of their parameters to adjust catchment‐scale water balance. We show that from both the hydrological likelihood and the modeling efficiency point of view it is preferable to explicitly represent intercatchment groundwater transfers. The surrogate corrective solutions tested in this paper (correcting or scaling factors applied to the climatic input data or to the catchment area) that are sometimes used in practice could be used on the sole grounds of streamflow simulation efficiency, but we show that they should be avoided since they may lead to obviously unrealistic corrections and consequently yield a similarly unrealistic distribution between evaporation streamflow and underground fluxes.
Charged particle periodicities in Saturn's outer magnetosphere
Authors: Carbary J. F. , Mitchell D. G. , Krimigis S. M. , Hamilton D. C. , Krupp N.
Published: June 2007

A Lomb periodogram analysis is applied to charged particle data from the LEMMS/CHEMS instruments on the Cassini spacecraft. The data represent count rates, averaged within 30 min bins, from electrons (28–330 keV) and protons and oxygen ions (2.8–236 keV) during 350 days in 2005 and all 365 days in 2006. Sun effects, spacecraft maneuvers, and measurements within 20 RS of Saturn were removed from the data prior to analysis. The main peaks in the frequency periodograms (or power spectra) were found within a frequency window from 9.5 hours to 12.5 hours. For signal‐to‐noise ratios exceeding 8, the periodograms within this window reveal a consistent peak near 10.80 hours (10 hours 48 min 36 sec) for all the charged particles regardless of energy or species. Even for lower signal‐to‐noise ratios, a peak near this period is generally present. The Lomb analyses are consistent with an azimuthal anomaly that rotates with a period of 10.80 hours.
Anaerobic phenanthrene mineralization by a carboxylating sulfate-reducing bacterial enrichment
Authors: Davidova Irene A , Gieg Lisa M , Duncan Kathleen E , Suflita Joseph M
Published: June 2007

Information on the susceptibility of higher molecular weight polynuclear aromatic hydrocarbons to anaerobic biodegradation is relatively rare. We obtained a sulfate-reducing bacterial enrichment capable of phenanthrene metabolism from a hydrocarbon-contaminated marine sediment. Phenanthrene degradation was in stoichiometric agreement with the theoretically expected amount of sulfate reduction and inhibited by molybdate. Mineralization of 14C-phenanthrene by the enrichment was confirmed by the recovery of the expected amount of 14CO2. Stable isotope studies with protonated or deuterated phenanthrene resulted in the detection of the correspondingly labeled phenanthrene carboxylic acid by gas chromatography–mass spectrometry. Comparison of the metabolite profile with a synthesized standard confirmed that the parent molecule was carboxylated at the C-2 position. Incorporation of 13C-bicarbonate into the carboxyl group implicated a direct carboxylation of phenanthrene as a likely key initial reaction. Denaturing gradient gel electrophoresis analysis of the enrichment showed only two major bands and 16S rRNA sequences obtained by cloning clustered with known hydrocarbon-degrading sulfate-reducing δ-proteobacteria, indicating their possible involvement in the anaerobic oxidation of phenanthrene via carboxylation as the initial activation reaction.
Biological and chemical sulfide oxidation in a Beggiatoa inhabited marine sediment
Authors: Preisler André , de Beer Dirk , Lichtschlag Anna , Lavik Gaute , Boetius Antje , Jørgensen Bo Barker
Published: June 2007

The ecological niche of nitrate-storing Beggiatoa, and their contribution to the removal of sulfide were investigated in coastal sediment. With microsensors a clear suboxic zone of 2–10 cm thick was identified, where neither oxygen nor free sulfide was detectable. In this zone most of the Beggiatoa were found, where they oxidize sulfide with internally stored nitrate. The sulfide input into the suboxic zone was dominated by an upward sulfide flux from deeper sediment, whereas the local production in the suboxic zone was much smaller. Despite their abundance, the calculated sulfide-oxidizing capacity of the Beggiatoa could account for only a small fraction of the total sulfide removal in the sediment. Consequently, most of the sulfide flux into the suboxic layer must have been removed by chemical processes, mainly by precipitation with Fe2+ and oxidation by Fe(III), which was coupled with a pH increase. The free Fe2+ diffusing upwards was oxidized by Mn(IV), resulting in a strong pH decrease. The nitrate storage capacity allows Beggiatoa to migrate randomly up and down in anoxic sediments with an accumulated gliding distance of 4 m before running out of nitrate. We propose that the steep sulfide gradient and corresponding high sulfide flux, a typical characteristic of Beggiatoa habitats, is not needed for their metabolic performance, but rather used as a chemotactic cue by the highly motile filaments to avoid getting lost at depth in the sediment. Indeed sulfide is a repellant for Beggiatoa.