bluuebunny/crossref_metadata_2025 huggingface dataset:
Shock-initiated exothermic reactions. I. The decomposition of nitrous oxide
Authors: Drummond LJ , Hiscock SW
Published: September 2006

Measurements of the speeds
of reflected shocks in mixtures of nitrous oxide- argon (6:94) were made using
thin film detectors for timing purposes. Initial temperatures behind the
reflected shocks were between 1670 and 1920�K and pressures were in the range
3-4 atm. The results indicate that at lower temperatures the initial
endothermic decomposition caused the shock to decelerate. At higher
temperatures, fast exothermic reactions rapidly accelerated the shock. Measured
shock speeds were thus average values. Consideration must be given, therefore,
to the degree of dilution by inert gas and the positions of timing stations and
windows relative to the end plate. This is illustrated by reference to previous
investigations of the rate constant for the decomposition of nitrous oxide.
Complexes of chromium(II) halides with triphenylphosphine oxide
Authors: Scaife DE
Published: September 2006

Complexes of divalent
chromium of the type CrX2,2Ph3PO,
with X = Cl, Br, I, have been prepared. With X = Br,
two forms exist. The spectra of CrCl2,2PhsPO and the
green form of CrBr2,2Ph3PO
indicate tetragonally distorted six-coordination of the chromium(II), with
bridging through the halogen atoms. The spectra of the yellow form of CrBr2,2Ph3PO and Cr12,2Ph8P0
suggest that these compounds have flattened tetrahedral coordination about the
chromium(II).

Spectra are reported for the
six-coordinate complexes CrI2,2Ph3PO,2THF,
CrBr2,2THF, and CrBr2,2CH3CN,
and X-ray powder data are reported for the last two compounds.

All the compounds reported have magnetic
susceptibilities following the Curie-Weiss law, with values of θ between 8
and 34� and values of μeff in the range 4.79-4.88 B.M.
Studies in the stereochemistry of zinc(II). VI. Zinc complexes with quadridentate Schiff bases
Authors: Batley GE , Graddon DP
Published: September 2006

Zinc complexes have been
prepared with Schiff bases formed from salicylaldehyde and
polymethylenediamines with chains of 2-9 carbon atoms. The anhydrous zinc
complexes of ligands with 2-3 carbon chains readily form 1 : 1 adducts with
water or bases such as pyridine; the ultraviolet and infrared spectra of these
anhydrous compounds indicate that they are polymeric with bridging oxygen
atoms, the zinc being 5-coordinate. The zinc complexes of ligands with carbon
chains of four or more atoms do not form adducts, even in pyridine solution,
and their spectra show that none of the oxygen atoms is bridging, the zinc
being 4-coordinate. The stereochemistry of the zinc appears to be determined
solely by steric effects: when the ligand is such that 4-coordination can produce
a tetrahedral environment, further coordination does not occur; when 4-coordination
cannot produce a tetrahedral environment, 5- coordination always occurs.
Radiation-induced reactions with cellulose. IV. Electron paramagnetic resonance studies of radical formation
Authors: Dilli S , Ernst IT , Garnett JL
Published: September 2006

The radiation-induced
formation of trapped radicals in cellulose, both in vacuum and air, has been
studied by e.p.r, spectroscopy. Factors affecting
radical concentration have been examined, including total dose, dose rate,
heat, cellulose pretreatment, and kinetics of radical decay. All spectra were
asymmetric in shape. Variables affecting line shape have been studied,
including oxygen, irradiation conditions such as the presence of water, acetic
acid, copper sulphate solution, methanol, ethanol, potassium iodide, and liquid
ammonia. The data indicate that the observed cellulose e.p.r,
spectrum is composed of an overlapping singlet with a triplet. Studies of
radical decay show that a significant concentration of e.p.r.
species still remains in irradiated cellulose after 4 years at ambient
temperature.
The chemistry of pyrrolic compounds. V. b-Methoxy- and b-hydroxyporphyrins
Authors: Chong R , Clezy PS
Published: September 2006

Making use of
dipyrrylmethane intermediates, the preparation of l- methoxy-2,3,4,5,6,8-hexamethylporphin
(V) is described. The attempted synthesis of the corresponding hydroxyporphyrin
has yielded a ketonic tetrapyrrole which is presumably a tautomer of the
desired compound. The structure of this material is discussed.
Thio derivatives of β-diketones and their metal chelates. VII. The visible-ultraviolet spectra of some monothio-b-diketones and their metal chelates
Authors: Chaston SHH , Livingstone SE
Published: September 2006

The electronic spectra of
3-mercapto-1,3-diphenylprop-2-en-1-one, PhC(SH)=CHCOPh, and its zinc(II), silver(I), cadmium(II),
mercury(II), and S-methyl derivatives are given and some provisional
assignments of the bands are made. The spectra indicate that the oxygen atom of
the ligand is weakly coordinated in the silver and cadmium complexes and that
in the mercury complex the ligand is coordinated through the sulphur atom only.
The spectra of two other monothio-β-diketones, R1C(SH)=CHCOR2
(R1 = R2 = Me, But), are also given.

The spectra of the nickel(II) chelates of
seven monothio-β- diketones are discussed and the bands are assigned as
metal d-d, metal- to-ligand, ligand-to-metal, and ligand-to-ligand transitions.
Cyclic phosphines and arsines. I. Reactions with metal carbonyls
Authors: Ang HG , West BO
Published: September 2006

A number of cyclic
phosphines (PR)n, where R = Ph, Me, Et, and n = 4 or 5, and
arsenobenzene (AsPh)6 has been found to
react with metal carbonyls to give coordination compounds such as (PPh)4Ni(CO)3,
(PR)5M(CO)n (where n = 5, 4, or 3, and M = Cr, Mo, or W),
(PR)4[Fe(CO)3]2, and (AsPh)6Mo(CO)4.
Reactions of free radicals with aromatic compounds in the gaseous phase. III. Kinetics of the reaction of methyl radicals with anisole (methoxybenzene)
Authors: Mulcahy MFR , Tucker BG , Williams DJ , Wilmshurst JR
Published: September 2006

The kinetics of the
reaction between methyl radicals and anisole have been studied at temperatures
between 453 and 539�K and total pressures between 10 and 30 torr.
The concentrations of methyl radicals ranged from 2 x 10-12 to 5 x
10-11 mole and those of anisole from 10-7 to mole cm-3.
The reaction proceeds mainly by the mechanism

������������������ C6H5OCH3+CH3·
→ C6H5OCH2·+CH4���������������� (1)����������������� C6H5OCH2·+CH3·
→ C6H5OC2H5�������������������� (2)���������������� ���������C6H5OCH2·
→ C6H5CHO+H·������������������ (3)

At 487�K attack on the
aromatic ring to yield methyl anisoles is about twelve times slower than
reaction (1). The Arrhenius parameters for reactions (1) and (8) are: log10(A1 cm3
mole-1 sec-1) = 11.7 � 0.3, and E1 = 10.5 �
0.8 kcal mole-1; log10(A8
sec-1) = 12.5, and E8 = 21 kcal mole-1. The
last two values are based on the assumption that the kinetics of reaction (2)
are similar to those of the recombination of methyl radicals. The rate of
reaction (1) is about half that of the corre- sponding reaction with toluene and about five times that of
the reaction with ethane in the above temperature range.
N.M.R. spectra and stereochemistry of the bipyridyls. I. Unsubstituted bridged biquaternary 2,2'-bipyridyls
Authors: Calder IC , Spotswood M , Tanzer CI
Published: September 2006

ABMX analysis of the N.M.R.
spectra of six bridged biquaternary salts of 2,2?-bipyridyl is reported. The
difference in chemical shift between H3(3?) and H5(5?) varies with the length
of the bridging group, and the results are discussed in relation to the probable
conformation of the salts. The several factors determining the difference in
chemical shift are discussed, and it is concluded that the diamagnetic
anisotropy of the neighbouring pyridinium ring is the major contributor, with
further significant contributions from the asymmetric distribution of positive
charge in the pyridinium ring. Interplanar angles are calculated and compared
with values estimated for the singly bridged biphenyls; evidence for mobile and
frozen conformations is presented.
N.M.R. spectra and stereochemistry of the bipyridyls. II. Dimethyl-substituted bridged biquaternary salts of 2,2'-bipyridyl
Authors: Spotswood TM , Tanzer CI
Published: September 2006

The analysis of the N.M.R.
spectra of nine dimethyl-substituted bridged biquaternary salts of 2,2?-bipyridyl
is reported, and the results are discussed in relation to the several factors
influencing the relative chemical shifts of heterocyclic ring protons and
methyl group protons. Interplanar angles are calculated for all compounds and
are shown to be in good agreement with angles estimated from molecular models
and in qualitative agreement with electronic spectral data. Compounds with 3,3?-dimethyl
substituents are shown to be in rigid dissymmetrically twisted conformations at
room temperature, and evidence is presented that conformational inversion in
the bipyridyl series is more difficult than in the corresponding singly bridged
biphenyl series. Six of the compounds reported here have not previously been
described.
Characterization of the cleavage products of human serum immunoglobulin disulphide bonds. I. S-Sulpho derivatives
Authors: Brackenridge CJ
Published: September 2006

An examination of
variables, including amount of catalyst, pH, sulphite concentration, specific
buffer salts, and time of reaction led to conditions for the quantitative
sulphitolysis of human serum immunoglobulin disulphide bonds. The cleavage was
carried out in the absence of dispersing agents, using air as oxidant and
cupric ions as catalyst. The treated protein was characterized by solubility,
exclusion chromatography, ultracentrifugation, and immunoelectrophoresis.

Separation into three fractions of
different molecular weight was achieved by passage through Sephadex G-200 gel.
Efforts to eliminate the proportion of aggregated material, which showed no
tendency to establish an equilibrium with the remaining two unaggregated
fractions, were largely unsuccessful. It was concluded that non-covalent forces
play a significant role in antibody interactions.

The isolated fractions were individually
characterized by sedimentation, heat precipitation, immunoelectrophoresis,
and quantitative analysis of amino-terminal residues. This led to the
demonstration of at least two polypeptide chains present in each fraction.
The mechanism of the oxidation of thiocyanate ion by peroxomonosulphate in aqueous solution. III. Interpretation of results
Authors: Smith RH , Wilson IR
Published: September 2006

The mechanistic implications of the results presented previously are
discussed. There is strong evidence that the reactants are in equilibrium with an
intermediate and some of the reactions of this intermediate have been observed;
thiooyanogen appears to be another intermediate. Schematically, the reaction
involves the pathways:
Diagram
The identity of X has not been established though suggestions are made.
The initial-rate procedure which was used to predict this scheme involves
some unusual assumptions and uses only a small portion of the available kinetic
data. Hence the proposed mechanism (and several alternatives) was tested by
numerical integration of the implied differential equations and comparison of
calculated and experimental kinetic curves. Such calculations avoided several of
the undesirable features of the analysis of initial rates and established the essential
adequacy of the above scheme; a detailed mechanism is proposed.
These calculations illustrate the usefulness of techniques of numerical
integration in evaluation of reaction mechanisms.
Chelate formation between lead(II) and 1,2,5,8-tetrahydroxyanthraquinone (quinalizarin): Spectrophotometric studies on the composition and stability
Authors: Srivastava KC , Banerji SK
Published: September 2006

The formation of a bluish
violet chelate between bivalent lead and 1,2,5,8-tetrahydroxyanthraquinone
(quinalizarin) with maximum absorption at 520mμ has been studied. The
chelate is soluble in aqueous ethanol. The composition of the chelate has been
determined by three methods. The chelate has a composition of 1 : 1 and is
stable at pH 6.1-8.5. The values of log K determined in 50% ethanolic medium by
the method of Dey et al., the continuous variation method, and the mole ratio
method, using absorbance data, are 4.1 � 0.1, 4.0 � 0.0, and 4.1� � 0.1 respectively at 30�, pH 6.3. The free
energy change of formation, calculated from the three values of log K, is -5.7
� 0.1, -5.6 � 0.0, and -5.7 � 0.1 kcal respectively.
The infrared spectra of aryl azides
Authors: Dyall LK , Kemp JE
Published: September 2006

The fundamental and
first-overtone azido antisymmetric stretching frequencies of 19 aryl azides
have been measured. It is demonstrated that the splitting of the V(NS)as
band is not due to the presence of conformers in solution, and probably does
not involve ?hot? bands. Fermi resonance explanations of the splitting are
suggested.
The formation of aromatic hydrocarbons at high temperatures. XXIX. Pyrolysis of 2-methylstyrene and 2-[1-14C]methylstyrene
Authors: Badger GM , Jolad SD , Spotswood TM
Published: September 2006

Pyrolyses of inactive and
of 14C-labelled 2-methylstyrene at 700� are reported. Sixteen
compounds were identified in the tar obtained following pyrolysis of the
inactive compound, and nine of these were isolated in sufficient purity and
yield for radiochemical analysis following pyrolysis of the labelled compound.
Probable mechanisms of formation of these compounds are discussed.
Cassytha alkaloids. IV. The alkaloids of Cassytha racemosa Nees (family Lauraceae)
Authors: Johns SR , Lamberton JA , Sioumis AA
Published: September 2006

Two new alkaloids from Cassytha racemosa Nees, family Lauraceae, have been shown
to be 1,2-dimethoxy-9,10-methylenedioxynoraporphine
(nornantenine) and 1,2-dimethoxy-9,10-methylenedioxy-7- oxodibenzo[de,g]quinoline. The structure of the first alkaloid follows
from the formation of nantenine on N-methylation, and of the second from its
preparation by the oxidation of nantenine. The previously known alkaloids
nantenine, isoboldine, laurotetanine, N- methyllaurotetanine, and
(+)-coclaurine have also been isolated, and thin-layer chromatograms indicate
the probable presence of laurelliptine as a minor alkaloid.
The chemical constituents of Galbulimima species. IX. The structures of himbadine and alkaloid G.B. 13
Authors: Mander LN , Prager RH , Rasmussen M , Ritchie E , Taylor WC
Published: September 2006

The structures of himbadine
(I) and its de-N-methyl derivative (II), alkaloid G.B. 13, proposed on the
basis of chemical and spectroscopic characterization were confirmed by several
partial syntheses from the ester alkaloid, himandrine (III), of known structure.
Marine pigments. VII. 3-Acetyl-2,5,6,7-tetrahydroxy- 1,4-naphthoquinone, a new spinochrome from Salmacis sphaeroides (Lovén)
Authors: Gough JH , Sutherland MD
Published: September 2006

3-Acetyl-2,5,6,7-tetrahydroxy-1,4-naphthoquinone
has been isolated from the spines and test of the echinoid Salmacis
sphaeroides (Loven). Its
structure has been determined by mass and p.m.r.
spectral evidence and hydrolysis to 2,5,6,7-tetra-hydroxy-1,4-naphthoquinone.
Implications for Community Health from Exposure to Bushfire Air Toxics
Authors: Reisen Fabienne , Brown Stephen K.
Published: September 2006

Environmental Context. Significant bushfires have recently occurred in Indonesia (1997), Europe (2002), Australia (2000–2001) and the USA (2003), and burned large areas over extended periods of time. They cause widespread and serious air pollution through the release of respirable particles and other toxic air contaminants. These large fire events have shown clear impacts on community health and have caused increasing concern about the impact of bushfire smoke, whether from accidental or planned fires, on the health of surrounding communities. Abstract. Bushfires can cause widespread air pollution through the emission of high levels of toxic air contaminants that affect the health of surrounding communities. This review of studies that have evaluated the health impacts of bushfires in North America, Australia and South-East Asia shows that the primary pollutant consistently exceeding air quality guidelines is particulate matter. Elevated levels of respirable particles are likely to be the major cause of the higher number of hospital visits and admissions for respiratory and/or cardiovascular treatment, increased mortality, and elevated respiratory-related symptoms that were observed in communities after major bushfire events. Morbidity effects were found to be mostly short-lived and reversible after exposure ceased, and were more prevalent among susceptible groups such as asthmatics, children, the elderly, and people with pre-existing respiratory and/or cardiac illnesses. Implications of such exposures to the Australian population will be discussed in relation to existing (urban) air quality measures and options for community response to bushfire events.
Seasonal and Diurnal Cycles of Dimethylsulfide, Dimethylsulfoniopropionate and Dimethylsulfoxide at One Tree Reef Lagoon
Authors: Broadbent Andrew , Jones Graham
Published: September 2006

Environmental Context. Coral reefs have now been highlighted as significant sources of dimethylsulfide and other organic sulfur compounds, which may be important for the formation of clouds over the ocean and climate regulation. However, no studies have reported the seasonal and diurnal cycles of these organic sulfur substances in reef waters. This study describes the cycling of dimethylsulfide and related organic substances at One Tree Reef, in the southern part of the Great Barrier Reef, as well as their production from staghorn coral in chamber experiments. The results suggest that coral reefs are significant sources of dimethylsulfide to reef waters and possibly the reef atmosphere, but the effect of this substance on the radiative climate over the Great Barrier Reef is unknown.
Abstract. Seasonal and diurnal studies conducted at One Tree Reef lagoon in the Great Barrier Reef (GBR) highlight increased production of dissolved dimethylsulfide, atmospheric dimethylsulfide, dissolved and particulate dimethylsulfoniopropionate, and dimethylsulfoxide during the summer months, and when the lagoon is moated with inter-reefal water. This production is due to both the growth of phytoplankton populations within the lagoon, and benthic corals and algae in or on sediments and attached to solid substrates. The relative importance of these two processes was not determined in this study, although benthic production from corals was shown to be significant in chamber experiments. The diurnal cycles of the organic sulfur substances measured at One Tree Reef provide unequivocal evidence that coral reefs produce significant quantities of these organic sulfur substances during the day and suggest that coral reefs could be significant sources of atmospheric dimethylsulfide.
Airborne Measurements of Trace Organic Species in the Upper Troposphere Over Europe: the Impact of Deep Convection
Authors: Colomb Aurélie , Williams Jonathan , Crowley John , Gros Valérie , Hofmann Rolf , Salisbury Gavin , Klüpfel Thomas , Kormann R. , Stickler Alexander , Forster Caroline , Lelieveld Jos
Published: September 2006

Environmental Context. In the upper troposphere, sources of HOx such as acetone, peroxides, and aldehydes can play an important role in governing the production and destruction of ozone. Convection (over both land and sea) carries gases that can contribute to increased levels of HOx to the upper troposphere. The chemical impact of convection on the continental upper troposphere over Europe is studied by sampling the upper troposphere. Mass spectrometry techniques are used to analyze the collected samples. Such a study should aid in understanding the impact meteorological events have on atmospheric chemistry. Abstract. The volume mixing ratios of several organic trace gases and ozone (O3) were measured in the upper troposphere over Europe during the UTOPIHAN-ACT aircraft campaign in July 2003. The organic trace gases included alkanes, isoprene, aromatics, iodomethane, and trichloroethylene, oxygenates such as acetone, methanol, formaldehyde, carbon monoxide, and longer-lived tracer species such as chlorofluorocarbons and halochloroflurocarbons. The aim of the UTOPIHAN-ACT project was to study the chemical impact of deep convection on the continental upper troposphere. A Lear Jet aircraft, based in Germany, was flown at heights between 6 and 13 km in the region 59°N–42°N to 7°W–13°E during July 2003. Overall, the convectively influenced measurements presented here show a weaker variability lifetime dependence of trace gases than similar measurements collected over the Mediterranean region under more stable high-pressure conditions. Several cases of convective outflow are identified by the elevated mixing ratios of organic species relative to quiescent background conditions, with both biogenic and anthropogenic influences detectable in the upper troposphere. Enhancement at higher altitudes, notably of species with relatively short chemical lifetimes such as benzene, toluene, and even isoprene indicates deep convection over short timescales during summertime. The impact of deep convection on the local upper tropospheric formaldehyde and HOx budgets is assessed.
Recent fire regime in peninsular Spain in relation to forest potential productivity and population density
Authors: Vázquez de la Cueva Antonio , García del Barrio José Manuel , Quero Marta Ortega , Palomares Otilio Sánchez
Published: September 2006

The potential productivity of forests is an important parameter in the evaluation of vegetation as a carbon sink. At the same time, potential productivity can be considered as an indicator of growth conditions and also as a measure of available fuel loads, which, in Mediterranean-type ecosystems, are a main factor of regional fire incidence. The present work deals with the relationship between an estimation of forest potential productivity and the fire incidence registered in peninsular Spain. Fire incidence was characterized by means of several fire regime variables. In order to contrast the patterns obtained, a similar analysis of the relationship between fire regime and human population density was also carried out. The results show that higher fire incidence was registered in more productive areas. Potential productivity was correlated to variables related to the number of fires and to the area burned, whereas the population density was also correlated to the number of fire variables and to the area burned, but with lower correlation coefficients. Although it is difficult to establish cause-and-effect relationships between complex phenomena that depend on a large number of factors, finding statistically significant relationships between fire incidence and the estimation of potential forest productivity used over a long time period is considered very relevant. These relationships make it necessary to take into account the fire regime when evaluating both forests and other terrestrial ecosystems as carbon sinks so as to meet the demands of the Kyoto Protocol.
Remote sensing of fire regimes in semi-arid Nusa Tenggara Timur, eastern Indonesia: current patterns, future prospects
Authors: Fisher Rohan , Bobanuba Wilfrida E. , Rawambaku Agus , Hill Greg J. E. , Russell-Smith Jeremy
Published: September 2006

Substantial areas of eastern Indonesia are semi-arid (with a pronounced dry season extending from April to November) with extensive areas of uncultivated vegetation dominated by savanna grasslands and woodlands. These are highly fire-prone, despite high population densities reliant on intensive subsistence agriculture and an official national fire policy that prohibits all burning. To date, no regional studies have been undertaken that reliably assess the seasonal extent and patterning of prescribed burning and wildfire. Focusing on two case studies in east Sumba (7000 km2) and central Flores (3000 km2) in the eastern Indonesian province of Nusa Tenggara Timur, the present paper addresses: (1) the efficacy of applying standard remote sensing and geographic information system tools as developed for monitoring fire patterns in savanna landscapes of adjacent northern Australia, for (2) describing the seasonal patterning of burning at village and broader regional scales in 2003 and 2004. Despite recurring cloudiness, which significantly affected daily fire detection of ‘hotspots’ from Advanced Very High Resolution Radiometer and Moderate Resolution Imaging Spectroradiometer sensors, fire mapping from Landsat imagery was undertaken successfully to reveal: (1) fires burnt an annual average of 29% of eastern Sumba (comprising mostly grassland savanna), and 11% of central Flores (with large forested areas); (2) most fire extent occurred in savanna grassland areas, and significantly also in cultivated lands and small remnant patches of forest; (3) most fire activity occurred under harsh, late dry season conditions; and (4) while the great majority of individual fires were less than 5 ha, some late dry season fires were hundreds of hectares in extent. The potential routine application of different image sensors for fire mapping and hotspot detection is considered in discussion.
Spatial patterns of forest fires in Canada, 1980 - 1999
Authors: Parisien Marc-André , Peters Vernon S. , Wang Yonghe , Little John M. , Bosch Erin M. , Stocks Brian J.
Published: September 2006

The present study characterized the spatial patterns of forest fires in 10 fire-dominated ecozones of Canada by using a database of mapped fires ≥200 ha from 1980 to 1999 (n = 5533 fires). Spatial metrics were used individually to compare measures of fire size, shape (eccentricity and complexity), clustering, and geographic orientation among ecozones and were used concurrently in a multivariate analysis. In addition, a set of factors that influence the fire regime at the ecozone level – topography, climate, fuels, and anthropogenic factors – was compared with the metric outputs. We found significant differences in all spatial metrics among ecozones. The multivariate analysis showed that the Montane Cordillera ecozone, which covers most of British Columbia, had the most distinctive fires: its fires were smaller, less complex, and had a more regular distribution. The fire regime descriptors of ecozones were useful to interpret the spatial variation of some spatial metrics, such as fire size, eccentricity, and clustering, but provided little insight into the mechanisms of patterns of fire complexity, which were shown to be sensitive to data quality. Our results provide additional information about the creation of spatially heterogeneous landscapes. Furthermore, they illustrate the potential use of spatial metrics for a more detailed characterization of fire regimes and provide novel information for ecosystems-based land management.
Ignition of mulch and grasses by firebrands in wildland - urban interface fires
Authors: Manzello Samuel L. , Cleary Thomas G. , Shields John R. , Yang Jiann C.
Published: September 2006

Firebrands or embers are produced as trees and structures burn in wildland–urban interface (WUI) fires. It is believed that firebrand showers created in WUI fires may ignite vegetation and mulch located near homes and structures. This, in turn, may lead to ignition of homes and structures due to burning vegetation and mulch. Understanding the ignition events that are due to firebrands is important to mitigate fire spread in communities. To assess the ignition propensity of such materials, simulated firebrands of uniform geometry, but in two different sizes, were allowed to impinge on fuel beds of shredded hardwood mulch, pine straw mulch, and cut grass. The moisture content of these materials was varied. Firebrands were suspended and ignited within the test cell of the Fire Emulator/Detector Evaluator (FE/DE) apparatus. The FE/DE was used to investigate the influence of an air flow on the ignition propensity of a fuel bed. Ignition regime maps were generated for each material tested as a function of impacting firebrand size, number of deposited firebrands, air flow, and material moisture content.
Fire histories in ponderosa pine forests of Grand Canyon are well supported: reply to Baker
Authors: Fulé Peter Z. , Heinlein Thomas A. , Covington W. Wallace
Published: September 2006

Fire scars and other paleoecological methods are imperfect proxies for detecting past patterns of fire events. However, calculations of long fire rotations in Grand Canyon ponderosa pine forests by Baker are not convincing in methodology or assumptions compared with fire-scar evidence of frequent surface fires. Patches of severe disturbance are a possible hypothesis to explain the relatively short age structure at the park, where ~12% fewer trees were older than 300 years compared with another unharvested northern Arizona site. However, mapped patterns of old trees as well as the evidence for frequent surface fire from fire scars, charcoal deposition studies, and evolutionary history are more consistent with the dominance of surface fire prior to c. 1880. The most relevant available evidence of fire recurrence at a given point, mean point fire intervals, had median values <16 years at all five study sites, close to filtered composite fire interval statistics (~6–10 years), but much lower than Baker’s calculated fire rotation values (55–110 years). The composite fire interval is not a uniquely important statistic or a numerical guideline for management, but one of many lines of evidence underscoring the ecological role of frequent surface fire in ponderosa pine forests.
CONSUMERS, CLIENTS OR CITIZENS? POLITICS, POLICY AND PRACTICE IN THE REFORM OF SOCIAL CARE
Authors: Clarke John
Published: September 2006

In the United Kingdom, New Labour articulated a consumerist view of the relationship between the public and public services. Its view of the citizen-as-consumer was the source of considerable political controversy and debate – both within and beyond public services. In this paper, I explore four aspects of consumerism in relation to social care in the United Kingdom: the political context of the rise of the ‘citizen-consumer’; the place of the citizen-consumer in social care policy; the responses of organisations providing social care to consumerist pressures and lastly the impact of consumerism on characteristic tensions in public services.
CARING FOR PEOPLE OR CARING FOR PROXY CONSUMERS?
Authors: Vabø Mia
Published: September 2006

Reforms that aim at empowering recipients as ‘consumers’ are often seen as self-evidently favourable and unavoidable. Current narratives on public-sector change describe the previous service regimes as rigid, uniform and inhumane, whereas reforms are regarded as offering a flexible and responsive future. Accordingly, consumerism has become a major driving force behind Nordic welfare reforms. This paper presents a more nuanced analysis of the suppositions about the past systems for home care services and offers a critical view on current reforms and the assumptions underlying them. Empirical examples are drawn from field research and personal interviews undertaken before (1995) and after (2000) the Norwegian home care service was caught in the wave of New Public Management reforms. The paper demonstrates how contractual arrangements implemented in the name of the consumer run counter to established practices based on personal trust and continuous dialogue on needs.
CONSUMERS IN CHARGE OF CARE: THE DUTCH PERSONAL BUDGET AND ITS IMPACT ON THE MARKET, PROFESSIONALS AND THE FAMILY
Authors: Kremer Monique
Published: September 2006

One of the icons of the Dutch welfare state reforms is the Personal Budget. With the introduction of this budget, care patients now have become consumers. They can manage their own budget and employ a care worker who cares according to the cared-for's wishes. The Personal Budget intends to create a market of care, as well as a shift of balance of power from professionals to care receivers. In practice, the market has not come yet. Instead, the majority of budget holders employ a family member. This is important as it gives recognition to informal carers. On the other hand, this may hamper the employment career of people with care responsibilities as they are likely to be constrained in their care relationship. Another caveat is that the Personal Budget undermines the professionalisation process of care workers. When consumers are in charge, care workers are no longer the custodians of their professional development. This may have unwelcome consequences for the quality of care in the long term.
Subclinical Exocrine Pancreatic Dysfunction Resulting From Decreased Cholecystokinin Secretion in the Presence of Intestinal Villous Atrophy
Authors: Nousia‐Arvanitakis Sanda , Fotoulaki Maria , Tendzidou Kyriaki , Vassilaki Constantina , Agguridaki Christina , Karamouzis Michael
Published: September 2006

The aim of this study was to evaluate the concept that pancreatic dysfunction in patients having gluten sensitivity (celiac disease [CD]) or cow's milk protein enteropathy (CMPE) may result from the lack of pancreatic enzyme stimulation in the absence or decrease of cholecystokinin (CCK) secretion caused by villous atrophy.

Patients and Methods:

The following parameters were measured: plasma CCK in response to a fatty meal and human pancreatic fecal elastase in 24 patients with CD while on gluten‐free diet and after gluten provocation and in 12 patients with CMPE at diagnosis and after a 6‐month period of cow's milk‐free diet. Intestinal mucosa morphology was examined by small bowel biopsy. Sixty‐three controls having no organic gastrointestinal problems were investigated once at the time of diagnostic evaluation.

Results:

Fasting CCK, obtained at a time when patients with CD or CMPE had normal intestinal mucosa, was significantly different from postprandial and comparable to that of the control group. Fasting CCK obtained from patients with villous atrophy was also statistically different, but not significantly, from the postprandial. Fasting and postprandial plasma CCK and fecal pancreatic elastase values from patients having normal intestinal mucosa were significantly higher than those obtained from patients with villous atrophy. Significant correlation of intestinal mucosa morphology and CCK with fecal elastase concentration was documented.

Conclusion:

Exocrine pancreatic dysfunction in individuals having villous atrophy may be the consequence of decreased CCK secretion. Cholecystokinin and pancreatic secretion is restored to normal, with intestinal mucosa regeneration.
Adequacy and Safety of an Infant Formula With a Protein/Energy Ratio of 1.8 g/100 kcal and Enhanced Protein Efficiency for Term Infants During the First 4 Months of Life
Authors: Turck Dominique , Grillon Christophe , Lachambre Emmanuelle , Robiliard Patrick , Beck Laurence , Maurin Jean‐Luc , Kempf Christian , Bernet Jean‐Paul , Marx Jacques , Lebrun Françoise , Van Egroo Louis‐Dominique
Published: September 2006

Objective:

Excess protein in infant formula may lead to renal overload and play a role in later obesity. The objective of this controlled, prospective, randomized, double‐blind study was to assess the suitability and safety of a modified protein content infant formula and its noninferiority as compared to a conventional formula.

Patients and Methods:

Healthy term infants age <7 days were either breast‐fed or randomized to be fed exclusively with a conventional casein‐predominant formula (protein/energy ratio: 2.6 g/100 kcal) or the isocaloric whey‐predominant study formula (protein/energy ratio: 1.8 g/100 kcal) for 120 days. Primary outcome was daily weight gain between D0 and D120 (noninferiority criterion: difference in daily weight gain ≤4 g). Secondary outcomes were daily gain in weight, length, head circumference and body mass index at monthly intervals. Tolerance and safety were assessed at each visit.

Results:

162 infants were enrolled, 84% of the formula‐fed infants and 36% of the breast‐fed infants completing the study. Mean daily weight gain from D0 to D120 in the formula‐fed groups differed by 0.38 g/day [95% CI: −2.59; 1.83] signifying the noninferiority of the study formula. Secondary outcomes did not differ between the 2 groups at any time and were comparable to outcomes in the breast‐fed group. Tolerance was good and adverse events were not different between study groups.

Conclusions:

The whey‐predominant study infant formula with a protein/energy ratio of 1.8 g/100 kcal and enhanced protein efficiency is safe and not inferior to a conventional formula in ensuring normal growth during the first four months of life.
Effect of Esophageal Ligation on Small Intestinal Development in Normal and Growth‐retarded Fetal Rabbits
Authors: Cellini Christina , Xu Jian , Buchmiller Terry L.
Published: September 2006

Objective:

The uninterrupted passage of amniotic fluid through the gastrointestinal tract is hypothesized to influence both intestinal and overall fetal somatic development. The effect of in utero esophageal ligation (EL) and therefore the exclusion of AF on somatic growth, small intestinal (SI) morphology and proliferation, and the expression of the glucose transporter sodium‐glucose cotransporter 1 (SGLT‐1) in both normal and intrauterine growth‐retarded (IUGR) fetal rabbits were evaluated.

Methods:

Thirteen pregnant New Zealand white rabbits underwent surgery on day 24 of their normal 31‐day gestation. Ipsilateral normal and IUGR fetuses underwent EL; the contralateral normal and IUGR fetuses underwent cervical exploration only forming 4 study groups (control‐normal, control‐IUGR, EL‐normal and EL‐IUGR). Rabbits were killed on day 31. Small intestinal villus height was measured, and epithelial cell proliferation was deter mined by proliferating cell nuclear antigen staining. Sodium‐glucose cotransporter 1 messenger RNA (mRNA) and protein expressions were analyzed. Statistical analysis was performed using 2‐way analysis of variance.

Results:

Esophageal ligation reduced fetal weight in IUGR by 15% and in normal by 10%. Villus height was significantly reduced in IUGR versus normal in both control and EL (control, P = 0.01; EL, P = 0.05). Intrauterine growth‐retarded fetuses had reduced SI proliferation versus normal in both control and EL. Sodium‐glucose cotransporter 1 mRNA production in EL fetuses was equal to control fetuses. Esophageal ligation‐normal and EL‐IUGR fetuses exhibited reduced protein levels and decreased staining for SGLT‐1 in villus enterocytes.

Conclusions:

Amniotic fluid exclusion by in utero EL reduced fetal weight. Small intestinal proliferation was not affected by EL. Although SGLT‐1 mRNA and protein were produced in all 4 groups, exposure of the fetal gastrointestinal tract to amniotic fluid appears necessary for proper brush border expression of nutrient transporter proteins.
Clinical Features of Celiac Disease in Indian Children
Authors: Poddar Ujjal , Thapa Babu Ram , Singh Kartar
Published: September 2006

Objective:

This study was designed to prospectively evaluate the clinical features of celiac disease (CD) in a large group of Indian children and to compare them with those from the West.

Patients and Methods:

Over a period of 5 years, a total of 549 children (≤14 years) with a clinical suspicion of CD were evaluated. Their detailed clinical features, investigations, and follow‐up data were recorded. Complete hemogram, endoscopic duodenal biopsy, and celiac serology were done in all of the cases. Celiac disease was diagnosed on the basis of modified European Society of Paediatric Gastroenterology, Hepatology and Nutrition criteria.

Results:

Celiac disease was diagnosed in 300 children; 39 were excluded because of lack of follow‐up or poor response to gluten‐free diet. The remaining 210 had normal villous architecture and served as controls. The mean (± standard deviation) age of children with CD was 6.7 ± 3 years, and the mean duration of symptoms was 3.5 ± 2.5 years. The majority (84%) presented with diarrhea; other features were failure to thrive in 91%, anemia in 84%, wasting in 87%, and stunting in 60% of cases. Among the serological tests, the best results were obtained with tissue transglutaminase. On follow‐up (19.4 ± 15.5 months), symptoms subsided in all cases of CD with a significant weight and height gain.

Conclusions:

Indian children with CD present late, with a significant delay in diagnosis. The majority presents with classic symptoms of diarrhea, failure to thrive, and anemia. There is a need for increasing awareness to pick up the atypical forms of the disease.
Pepsin, a Reliable Marker of Gastric Aspiration, Is Frequently Detected in Tracheal Aspirates From Premature Ventilated Neonates
Authors: Farhath Sabeena , Aghai Zubair H. , Nakhla Tarek , Saslow Judy , He Zhaoping , Soundar Sam , Mehta Devendra I.
Published: September 2006

Objectives:

To determine the frequency of pepsin detection in tracheal aspirate (TA) samples of mechanically ventilated premature neonates and its association with feedings and methylxanthine therapy.

Patients and Methods:

Serial TA samples (days 1, 3, 5, 7, 14, 21, 28 and >28vdays) were collected from premature neonates receiving ventilatory support. An enzymatic assay with a fluorescent substrate was used to detect pepsin. Pepsin was also measured in 10 serum samples collected in conjunction with the TA samples from 8 neonates.

Results:

A total of 239 TA samples was collected from 45 premature neonates (mean birth weight, 762 ± 166 g; mean gestational age, 25.5 ± 1.5 wk). Pepsin was detectable in 222 of 239 TA samples (92.8%) and in none of the serum samples. Pepsin was significantly lower on day 1 (mean, 170 ± 216 ng/mL) when compared with all other time points (P < 0.05). Mean concentration of pepsin was significantly lower when infants were unfed (265 ± 209 ng/mL) compared with levels during feeding (390 ± 260 ng/mL, P = 0.02). The mean level of pepsin was significantly higher in infants during xanthine therapy (419 ± 370 ng/mL) compared with no xanthine therapy (295 ± 231 ng/mL, P = 0.037).

Conclusion:

Pepsin, a marker of gastric contents, was detected in more than 92% of TA samples from premature infants on mechanical ventilation. The level of pepsin was higher in fed infants when compared with unfed infants. Xanthine therapy was also associated with increased pepsin in TA samples. Chronic aspiration of gastric contents may worsen lung disease in premature infants.
Zinc Supplementation for the Treatment of Diarrhea in Infants in Pakistan, India and Ethiopia
Authors: Fischer Walker Christa L. , Bhutta Zulfiqar A. , Bhandari Nita , Teka Telahun , Shahid Farhana , Taneja Sunita , Black Robert E. ,   Zinc Study Group
Published: September 2006

Objective:

This randomized, placebo controlled trial was designed to assess the safety and efficacy of 10‐mg zinc supplementation for the treatment of acute diarrhea in infants.

Methods:

A total of 1110 infants aged 28 days to 5 months with acute diarrhea were enrolled and randomized to receive either zinc (n = 554) or placebo (n = 556) for 14 days. Diarrhea history, anthropometric status, breast‐feeding status and socioeconomic indicators were assessed at baseline. The homes of all infants were visited every 3 days until the diarrhea episode was over. The number of stools, presence of blood and additional illnesses were recorded daily.

Results:

The geometric mean duration of the diarrhea episode was 0.21 days longer among infants receiving zinc versus those receiving placebo, but this was not statistically significant and no difference was observed after controlling for sex, exclusive breast‐feeding and length for age Z score. There were no differences in any subgroup (ie, sex, baseline length for age Z score, exclusive breast‐feeding or site after controlling for the remaining subgroup variables). There were no differences in reported stool frequency or among the proportion of episodes lasting longer than 7 days. Rates of vomiting were similar in the zinc and placebo groups.

Conclusions:

Young infants do not appear to benefit from zinc supplementation for the treatment of diarrhea.
Azathioprine Monotherapy for Maintenance of Remission in Pediatric Patients With Autoimmune Hepatitis
Authors: Banerjee Sanjoy , Rahhal Riad , Bishop Warren P.
Published: September 2006

Autoimmune hepatitis (AIH) is a chronic disorder characterized by unresolving liver inflammation and has a fluctuating clinical course. Standard therapy has been corticosteroids given daily, alone or in combination with azathioprine (AZA). The potential for significant side effects from prolonged corticosteroid use remains high. To date, no pediatric literature describes long‐term AZA monotherapy after induction of remission with corticosteroids. We conducted a retrospective chart review from 1990 to 2002, which revealed 8 patients with AIH. Three patients were excluded because of other diseases requiring continued or intermittent use of corticosteroids. The time to complete biochemical remission on corticosteroids and AZA was 230 days (range, 74‐288 days). Azathioprine was introduced early following the diagnosis (range, 1‐35 days). All 5 patients were successfully weaned off corticosteroids after a median of 378 days and were maintained on AZA monotherapy for a median of 37 months (range, 28‐82 months). One patient had a disease exacerbation on AZA monotherapy 75 months after the discontinuation of corticosteroids. She responded quickly to a corticosteroid burst and has been on AZA monotherapy for 7months. One patient relapsed after self‐discontinuing all medications. Long‐term remission of AIH was possible in our case series with the early introduction and maintenance treatment with AZA as monotherapy.
Acid and Nonacid Gastro‐oesophageal Reflux in Neurologically Impaired Children
Authors: Del Buono Raffaele , Wenzl Tobias G. , Rawat David , Thomson Mike
Published: September 2006

Objectives:

The diagnosis of gastro‐oesophageal reflux (GOR) is more difficult in children with neurological impairment because symptoms are often less interpretable and frequently go undetected. The use of combined pH and multiple intraluminal impedance allows for the detection of both acid (pH < 4) and nonacid (pH > 4) GOR episodes, in addition to the height of the refluxate and the total acid and bolus clearance time in this cohort.

Methods:

Sixteen neurologically impaired children (9 were fed nasogastrically, 7 were fed orally) underwent 12‐hour combined pH and multiple intraluminal impedance.

Results:

There were a total of 425 reflux episodes during the study period, of which 239 (56.2%) were nonacid. The median of reflux episodes per hour was 1.8 (range, 0.2‐6.3/h). The median height of the refluxate was 1.5 channels (range, 1.1‐2.9); and 71.3% of reflux episodes reached the upper oesophagus, of which 52.4% were nonacid reflux events. On average there were more GOR events (both acid and nonacid) in the children who were fed via a nasogastric tube, and the median height of refluxate was also higher in this group. However, the median acid clearance time was longer (both proximal and distal) in the children who were fed orally (28.6 s vs 16.2 s proximally; 67.9 s vs 38.3 s distally). The median acid clearance time (21.7 s proximally; 39.5 s distally) was longer when compared with bolus clearance (14.9 s).

Conclusions:

More than half of the reflux events in neurologically impaired children are nonacidic and would therefore go undetected by conventional pH metry. There are more reflux events in children fed nasogastrically than oral‐fed children.
Antiemetics for Children With Gastroenteritis
Authors: Albano Fabio , Bruzzese Eugenia , Spagnuolo Maria Immacolata , De Marco Giulio
Published: September 2006

Antiemetics are not included for treatment of vomiting associated with acute gastroenteritis (AGE) in children by standard guidelines. We performed a survey to determine antiemetic prescribing rates by Italian pediatricians. A structured questionnaire was distributed at a pediatric national conference. The majority of responders reported prescribing antiemetics for pediatric gastroenteritis. Although there is insufficient evidence to justify their use, the use of antiemetics is widely present among pediatricians.