bluuebunny/crossref_metadata_2025 huggingface dataset:
Polony DNA Sequencing
Authors: Porreca Gregory J. , Shendure Jay , Church George M.
Published: November 2006

Polony DNA sequencing provides an inexpensive, accurate, high‐throughput way to resequence genomes of interest by comparison to a reference genome. Mate‐paired in vitro shotgun genomic libraries are produced and clonally amplified on microbeads by emulsion PCR. These serve as templates for sequencing by fluorescent nonamer ligation reactions on a microscope slide. Each sequencing run results in millions of 26‐bp reads that can be aligned to the reference genome, allowing the identification of differences between sequences.
Detection of Protein‐Protein Interactions by Coprecipitation
Authors: Elion Elaine A.
Published: November 2006

Coprecipitation of proteins from whole‐cell extracts is a valuable approach to test for physical interactions between proteins of interest. This unit describes basic approaches to immunoprecipitating tagged proteins from whole‐cell extracts. The approaches described can be adapted for other systems. In a typical experiment, as described here, cells are lysed and a whole‐cell extract is prepared under nondenaturing conditions. The protein is precipitated from the lysate with a solid‐phase affinity matrix, and the precipitate is tested for the presence of a second specifically associated protein. The approach can be used for native or epitope‐tagged proteins for which antibodies are available, or for recombinant proteins that have been engineered to bind with high affinity to a molecule that can be coupled to a solid‐phase matrix.
Overview of Gene Targeting by Homologous Recombination
Authors: Mortensen Richard
Published: November 2006

Formerly UNIT 9.15, this unit has been moved to the opening spot of our new chapter on Embryonic Stem Cell technology. The unit has also been updated, and now includes information about the Cre‐lox and FlP/FRT recombinase systems.
Ex Vivo and In Vivo Gene Delivery to the Brain
Authors: Suhonen Jaana , Ray Jasodhara , Blömer Ulrike , Gage Fred H. , Kaspar Brian
Published: November 2006

This unit describes methods for grafting genetically modified cells for ex vivo delivery of specific genes into the rat brain and direct delivery of transgenes to brain cells in vivo using recombinant viral vectors. These methods assess the function of a gene in the brain. The ex vivo approach of gene transfer to the nervous system depends on genetic manipulation of cells in vitro prior to grafting of the cells into the brain to enable production of a transgene at physiologically significant levels for a long period of time. This unit also includes procedures for transcardial perfusion to fix the tissue prior to analysis of expression and for sectioning of brains by use of a freezing sledge microtome. Thionine staining of tissue sections is also described.
Analysis of a regularized, time‐staggered discretization applied to a vertical slice model
Authors: Dubal Mark , Staniforth Andrew , Wood Nigel , Reich Sebastian
Published: November 2006

A regularized and time‐staggered discretization of the two‐dimensional, vertical slice Euler equation set is described and analysed. A linear normal mode analysis of the time‐discrete system indicates that unconditional stability is obtained, for appropriate values of the regularization parameters, for both the hydrostatic and non‐hydrostatic cases. Furthermore, when these parameters take their optimal values, the stability behaviour of the normal modes is identical to that obtained from a semi‐implicit discretization of the unregularized equations. © Crown Copyright 2006. Reproduced with the permission of the Controller of HMSO. Published by John Wiley & Sons, Ltd.
Feasibility of future epidemiological studies on possible health effects of mobile phone base stations
Authors: Neubauer Georg , Feychting Maria , Hamnerius Yngve , Kheifets Leeka , Kuster Niels , Ruiz Ignacio , Schüz Joachim , Überbacher Richard , Wiart Joe , Röösli Martin
Published: November 2006

The increasing deployment of mobile communication base stations led to an increasing demand for epidemiological studies on possible health effects of radio frequency emissions. The methodological challenges of such studies have been critically evaluated by a panel of scientists in the fields of radiofrequency engineering/dosimetry and epidemiology. Strengths and weaknesses of previous studies have been identified. Dosimetric concepts and crucial aspects in exposure assessment were evaluated in terms of epidemiological studies on different types of outcomes. We conclude that in principle base station epidemiological studies are feasible. However, the exposure contributions from all relevant radio frequency sources have to be taken into account. The applied exposure assessment method should be piloted and validated. Short to medium term effects on physiology or health related quality of life are best investigated by cohort studies. For long term effects, groups with a potential for high exposure need to first be identified; for immediate effect, human laboratory studies are the preferred approach. Bioelectromagnetics 28:224–230, 2007. © 2006 Wiley‐Liss, Inc.
Effects of 50 Hz sinusoidal magnetic fields on Hsp27, Hsp70, Hsp90 expression in porcine aortic endothelial cells (PAEC)
Authors: Bernardini Chiara , Zannoni Augusta , Turba Maria Elena , Bacci Maria Laura , Forni Monica , Mesirca Pietro , Remondini Daniel , Castellani Gastone , Bersani Ferdinando
Published: November 2006

The aim of the present study was to investigate the influence of 50 Hz sinusoidal magnetic field on Hsp27, Hsp70, and Hsp90 expression in a model of primary culture of porcine aortic endothelial cells (PAEC). We took into consideration the Hsp profile in terms of mRNA expression, protein expression and protein localization inside the cells. The choice of the cell system was motivated by the involvement of the endothelial cells in the onset of many diseases; moreover, only few reports describe the effects of extremely low frequency magnetic fields (ELF‐MFs) on such cells. ELF‐MF exposure induced an increase in the mRNA levels of the three proteins, which was statistically significant for Hsp70. On the contrary, we did not observe any influence on Hsp27, Hsp70, and Hsp90 protein levels. Analysis in situ by immunofluorescence revealed that ELF‐MF exposure affected the cellular distribution of Hsp27; in particular a partial relocalization in the nucleus was observed. Bioelectromagnetics 28:231–237, 2007. © 2006 Wiley‐Liss, Inc.
Mechanisms of DNA binding determined in optical tweezers experiments
Authors: McCauley Micah J. , Williams Mark C.
Published: November 2006

The last decade has seen rapid development in single molecule manipulation of RNA and DNA. Measuring the response force for a particular manipulation has allowed the free energies of various nucleic acid structures and configurations to be determined. Optical tweezers represent a class of single molecule experiments that allows the energies and structural dynamics of DNA to be probed up to and beyond the transition from the double helix to its melted single strands. These experiments are capable of high force resolution over a wide dynamic range. Additionally, these investigations may be compared with results obtained when the nucleic acids are in the presence of proteins or other binding ligands. These ligands may bind into the major or minor groove of the double helix, intercalate between bases or associate with an already melted single strand of DNA. By varying solution conditions and the pulling dynamics, energetic and dynamic information may be deduced about the mechanisms of binding to nucleic acids, providing insight into the function of proteins and the utility of drug treatments. © 2006 Wiley Periodicals, Inc. Biopolymers 85:154–168, 2007.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Trends in percutaneous versus surgical revascularization of unprotected left main coronary stenosis in the drug‐eluting stent era—a report from the American College of Cardiology‐National Cardiovascular data registry (ACC‐NCDR)
Authors: Huang Henry W. , Brent Bruce N. , Shaw Richard E.
Published: November 2006

Objectives:

We sought to determine how practice patterns for unprotected left main stenosis have changed with the advent of drug‐eluting stents (DES).

Background:

Percutaneous coronary intervention (PCI) of unprotected left main coronary stenosis has been controversial.

Methods:

We analyzed data submitted to the American College of Cardiology‐National Cardiovascular Data Registry (ACC‐NCDR) between January 1, 2002 and December 31, 2004 from 1,276,582 cardiac catheterizations at 417 institutions. Of these, 53,548 (4.2%) had left main stenosis >50% and no prior CABG. After excluding the unrevascularized, the patient sample (N = 32,562) was analyzed for PCI vs. CABG. Data was stratified by year/quarter, bare metal stent vs. DES, elective vs. urgent/emergent situations, LVEF < or ≥40%, and %left main and RCA stenosis.

Results:

Of unprotected left main revascularizations from 2002 to 2004, PCI increased from 17.0% to 21.9%, while CABG decreased from 83.0% to 78.1% (P < 0.0001). In 2002, bare metal stents were used for all PCIs; in 2004, bare metal stent use was only 25.5%, while DES use was 74.5% (P < 0.0001). Of elective procedures, PCI rose from 19.1% to 27.5% while CABG fell from 80.9% to 72.5% (P < 0.0001). Similar trends, all significant, were seen in every clinical situation.

Conclusions:

In the era of DES, the rate of PCI for unprotected left main stenosis has risen, while CABG has declined. These findings are seen across varying clinical situations, including elective procedures. DES have rapidly and largely replaced bare metal stents for PCI of unprotected left mains. However, PCI is still chosen less frequently than CABG for unprotected left main revascularization. © 2006 Wiley‐Liss, Inc.
Mitral valve hemodynamic effects of percutaneous edge‐to‐edge repair with the MitraClip™ device for mitral regurgitation
Authors: Herrmann Howard C. , Rohatgi Sameer , Wasserman Hal S. , Block Peter , Gray William , Hamilton Andrew , Zunamon Alan , Homma Shunichi , Di Tullio Marco R. , Kraybill Kimberly , Merlino John , Martin Randy , Rodriguez Leonardo , Stewart William J. , Whitlow Patrick , Wiegers Susan E. , Silvestry Frank E. , Foster Elyse , Feldman Ted
Published: November 2006

Introduction: The Endovascular Valve Edge‐to‐Edge REpair STudies (EVEREST) are investigating a percutaneous technique for edge‐to‐edge mitral valve repair with a repositionable clip. The effects on the mitral valve gradient (MVG) and mitral valve area (MVA) are not known. Methods: Twenty seven patients with moderate to severe or severe mitral regurgitation (MR) were enrolled. Echocardiography was performed preprocedure, at discharge, and at 1, 6, and 12 months. Mean MVG was measured by Doppler and MVA by planimetry and pressure half‐time, and evaluated in a central core laboratory. Pre‐ and postclip deployment, simultaneous left atrial/pulmonary capillary wedge and left ventricular pressures were obtained in eight patients. Results: Three patients did not receive a clip, six patients had their clip(s) explanted by 6 months (none for mitral stenosis), and four were repaired with two clips. Results are notable for a slight increase in mean MVG by Doppler postclip deployment (1.79 ± 0.89 to 3.31 ± 2.09 mm Hg, P < 0.01) and an expected decrease in MVA by planimetry (6.49 ± 1.61 to 4.46 ± 2.14 cm2, P < 0.001) and by pressure half time (4.35 ± 0.98 to 3.01 ± 1.42 cm2, P < 0.05). There were no significant changes in hemodynamic parameters postclip deployment by direct pressure measurements. There was no change in MVA by planimetry from discharge to 12 months (3.90 ± 1.90 to 3.79 ± 1.54 cm2, P = 0.78). Conclusions: Echocardiographic and hemodynamic measurements after percutaneous mitral valve repair with the MitraClip show an expected decrease in mitral valve area with no evidence of clinically significant mitral stenosis either immediately after clip deployment or after 12 months of follow‐up. © 2006 Wiley‐Liss, Inc.
Radiation‐induced xerostomia in patients with head and neck cancer
Authors: Dirix Piet , Nuyts Sandra , Van den Bogaert Walter
Published: November 2006

A dry mouth or xerostomia is one of the most common complications during and after radiotherapy for head and neck cancer, because irreparable damage is caused to the salivary glands, which are included in the radiation fields. Xerostomia not only significantly impairs the quality of life of potentially cured cancer patients, it may also lead to severe and long‐term oral disorders. Because management of xerostomia is rarely effective, prevention is paramount. Several strategies have been developed to avoid radiation‐induced salivary dysfunction without compromising definitive oncologic treatment. These include salivary gland‐sparing radiation techniques, such as 3‐dimensional conformal or intensity‐modulated radiotherapy, concomitant cytoprotectants, and surgical salivary gland transfer. However, these preventive approaches are not applicable to all patients, and comprehensive scientific research that incorporates new biological insights is warranted to optimize the therapeutic index of radiotherapy for head and neck cancer. Cancer 2006. © 2006 American Cancer Society.
Markers of absorption and synthesis of cholesterol in men with type 1 diabetes
Authors: Gylling Helena , Laaksonen David E. , Atalay Mustafa , Hallikainen Maarit , Niskanen Leo , Miettinen Tatu A.
Published: November 2006

Background and methods

Serum cholestanol and plant sterol ratios to cholesterol, surrogate markers of cholesterol absorption, are assumed to be high in type 1 diabetes (T1D), and the ratios of cholesterol precursor sterols (markers of synthesis) are assumed to be low reflecting downregulated cholesterol synthesis. To this end, we measured serum sterols with gas‐liquid‐chromatography in 56 men with T1D and in 18 controls to evaluate cholesterol metabolism. Subjects were categorised into tertiles by the cholestanol to cholesterol ratio of controls indicating low to high absorption of cholesterol.

Results

The ratios of the synthesis markers were negatively related to the absorption markers in controls, but less consistently in T1D. The absorption markers were positively related to each other, but interrelation of the synthesis markers was less consistent in T1D. In the low absorbers the absorption markers were higher in T1D than in controls (e.g. sitosterol ratio 173 ± 9 in T1D vs 135 ± 11 102 × mmol/mol of cholesterol in controls, p < 0.05). In the high absorbers, the absorption markers were similar in T1D and controls, but the synthesis markers were higher in T1D than in controls (e.g. lathosterol ratio 154 ± 10 in T1D vs 120 ± 5 102 × mmol/mol of cholesterol in controls, p < 0.05).

Conclusions

Absorption and synthesis of cholesterol are less closely related to each other in T1D than in controls, but the markers of cholesterol absorption are interrelated also in T1D. Absorption of cholesterol is higher in T1D than in controls within the range of low absorption, but similar in those with relatively high cholesterol absorption. Copyright © 2006 John Wiley & Sons, Ltd.
Inverse drug screens: a rapid and inexpensive method for implicating molecular targets
Authors: Adams Dany S. , Levin Michael
Published: November 2006

Identification of gene products that function in some specific process of interest is a common goal in developmental biology. Although use of drug compounds to probe biological systems has a very long history in teratology and toxicology, systematic hierarchical drug screening has not been capitalized upon by the developmental biology community. This “chemical genetics” approach can greatly benefit the study of embryonic and regenerative systems, and we have formalized a strategy for using known pharmacological compounds to implicate specific molecular candidates in any chosen biological phenomenon. Taking advantage of a hierarchical structure that can be imposed on drug reagents in a number of fields such as ion transport, neurotransmitter function, metabolism, and cytoskeleton, any assay can be carried out as a binary search algorithm. This inverse drug screen methodology is much more efficient than exhaustive testing of large numbers of drugs, and reveals the identity of a manageable number of specific molecular candidates that can then be validated and targeted using more expensive and specific molecular reagents. Here, we describe the process of this loss‐of‐function screen and illustrate its use in uncovering novel bioelectrical and serotonergic mechanisms in embryonic patterning. This technique is an inexpensive and rapid complement to existing molecular screening strategies. Moreover, it is applicable to maternal proteins, and model species in which traditional genetic screens are not feasible, significantly extending the opportunities to identify key endogenous players in biological processes. genesis 44:530–540, 2006. Published 2006 Wiley‐Liss, Inc.
Influence of polymorphisms in xenobiotic‐metabolizing genes and DNA‐repair genes on diepoxybutane‐induced SCE frequency
Authors: Laczmanska Izabela , Gil Justyna , Karpinski Pawel , Stembalska Agnieszka , Kozlowska Joanna , Busza Halina , Trusewicz Alicja , Pesz Karolina , Ramsey David , Schlade‐Bartusiak Kamila , Blin Nikolaus , Sasiadek Maria Malgorzata
Published: November 2006

Analysis of the combined effects of polymorphisms in genes encoding xenobiotic metabolizing enzymes (XMEs) and DNA repair proteins may be a key to understanding the role of these genes in the susceptibility of individuals to mutagens. In the present study, we performed an in vitro experiment on lymphocytes from 118 healthy donors that measured the frequency of diepoxybutane (DEB) induced sister chromatid exchanges (SCEs) in relation to genetic polymorphisms in genes coding for XMEs (CYP1A1, CYP2E1, GSTT1, EPHX, and NAT2), as well as DNA repair proteins (XRCC1, XRCC2, XRCC3, XPD, XPA, XPC, XPG, XPF, ERCC1, BRCA1, NBS1, and RAD51). We found that GSTT1(−) and CYP2E1 c1/c2 polymorphisms were associated with higher DEB‐induced SCE frequencies, and that NAT2 G590A was associated with lower SCE induction by DEB. Analysis of the effect of pairs of genes showed that for a fixed GSTT1 genotype, the SCE level increased with an increasing number of Tyr alleles in EPHX codon 113. We found that among GSTT1(+) individuals the DEB‐induced SCE level was significantly lower when the EPHX 139 codon was His/Arg rather than His/His. An interaction between polymorphisms in CYP2E1 and at EPHX codon 113 was also observed. The results of our study confirm observations in cancer patients and in people exposed to xenobiotics indicating that sensitivity to mutagens depends upon a combined effect of a variety of “minor impact” genes. Moreover, our results indicate that polymorphisms in genes coding for XMEs have a greater influence on the genotoxic activity of DEB, measured by DEB‐induced SCE frequency, than polymorphisms in genes encoding DNA repair proteins. Environ. Mol. Mutagen. 47:, 2006. © 2006 Wiley‐Liss, Inc.
Distribution of paraoxonase‐1 gene polymorphisms and enzyme activity in a Peruvian population
Authors: Cataño Héctor C. , Cueva Jayme L. , Cardenas Anthony M. , Izaguirre VÍctor , Zavaleta Amparo I. , Carranza Elizabeth , Hernández Antonio F.
Published: November 2006

Paraoxonase‐1 (PON1) is a serum esterase associated with high density lipoproteins and capable of detoxifying toxic metabolites of organophosphorus (OP) compounds. Two major polymorphisms have been described in the coding region of the PON1 gene at positions 192 and 55 and at least five in the 5′‐regulatory region, the most important at position −108. Depending on the substrate, PON1 192 Q/R polymorphism can affect PON1 enzymatic activity. In the present study, we have determined the distribution of the PON1 192 Q/R and −108 C/T polymorphisms in a Peruvian population and compared the distribution of these polymorphisms with those of other world populations. PON1 phenotype and enzyme activity also were measured as they can influence the population resistance to the toxicity of OP compounds. The genotype distribution at position 192 was: QQ = 0.236, QR = 0.607, and RR = 0.157; and distribution at position −108 was: CC = 0.315, CT = 0.596, and TT = 0.089. The frequencies of the high activity R and C alleles were 0.461 and 0.613, respectively. The frequency of the PON1 192 Q allele was significantly lower than that of American, Caucasian‐American, European‐Brazilian, and Costa Rican samples. Outside the American continent, the frequency of this allele was lower than for all European countries, Thais, and Indians, but higher than for Chinese or Japanese. Regarding the toxicological importance of these polymorphisms, it was inferred that PON1 phenotyping (assessment of the R alloform) and genotyping (determination of the PON1 –108TT genotype) could be helpful as individual markers of susceptibility. PON1 phenotyping may be useful in further epidemiological studies involving agriculture workers occupationally exposed to OP compounds in developing countries. Environ. Mol. Mutagen. 47:, 2006. © 2006 Wiley‐Liss, Inc.
Stilbazolium merocyanine dye determination in different solutions, concentrations and colloids using SERS
Authors: Pajchrowski Grzegorz , Abdali Salim , Norbygaard Thomas
Published: November 2006

Surface‐enhanced Raman scattering (SERS) measurements were carried out on stilbazolium merocyanine dye in methanol and pyridine solvents. Both solutions were measured in a series of concentrations covering a range of 5 × 10−5Mto 5 × 10−8M. In these measurements, Ag and Au colloids were used, and the results have shown that Ag colloids yield better enhancement in the Raman spectra of this dye. Moreover, the effect of adding NaCl solution to the SERS samples was also studied. All measurements were carried out using the state‐of‐the‐art ChiralRaman instrument, which utilizes a 532 nm laser source. We report here on the success of using SERS to obtain Raman spectra of merocyanine dye at very low concentrations in an attempt to find a new approach that can be used for further investigations of the dye. The SERS spectra are reported here, and the results from different solutions, colloids, concentrations and pH values are compared. Copyright © 2006 John Wiley & Sons, Ltd.
Interactions of lactoferricin B derivatives with model cell membrane studied by Raman spectroscopy
Authors: Ianoul A. , Westwick H. , Nowacka L. , Quan B.
Published: November 2006

In this work, we employed Raman spectroscopy to study the effect of the antimicrobial peptide lactoferricin B (LfB) on model cell membranes. We used two derivatives of LfB (RRWQWRMKKLG and RRWQWR) with broad‐spectrum activity against gram‐positive and gram‐negative bacteria, fungus, viruses and tumors. Raman spectra of the peptides showed no conformational change in the temperature range 4–60 °C. The positions of the amide I and amide III bands suggest that in an aqueous solution these peptides preferentially adopt a random coil‐like conformation. We also investigated the effect the peptides had on the melting behavior of model cell membranes composed of zwitterionic lipid dipalmitoylglycero‐phosphocholine (DPPC) and anionic lipid dipalmitoylglycero‐phosphoglycerol (DPPG). Raman CH stretching bands were used to follow the melting of the lipid vesicles. We found that the melting of DPPC lipid vesicles is not affected by the presence of the peptides, while the presence of the peptides reduced cooperativity of the phase transition for anionic DPPG vesicle, suggesting that both peptides interact strongly and specifically with this model cell membrane composed of anionic lipid. Copyright © 2006 John Wiley & Sons, Ltd.
The water relations of some dried fruits, vegetables and plant products
Authors: Gane R.
Published: November 2006

The water contents of some dehydrated plant products have been determined in atmospheres of known humidity within the range 0% to 80% saturation, usually at a temperature of 50° F. (10° C.) and also at 98–6° F. (37° C), 140° F. (60° C.) and 176° F. (80° C.) with dried potato and dried carrot.

The non‐diffusible colloids and soluble constituents each play a definite part in affecting the water content at any humidity; the colloids have a relatively high water content at low humidities and the soluble constituents have a low water content.

The humidity/water relations of mechanical mixtures, such as soup powders, can be calculated from the proportions and properties of the constituents.
The colorimetric determination of aluminium in silicate materials
Authors: Robertson George
Published: November 2006

Two methods are outlined for the colorimetric determination of aluminium in the presence of iron. They differ only in the reagent used to inhibit the iron colour, the final pu of the lake and the amount of iron that can be present. Thioglycollic acid and hydroxylamine hydrochloride are used to prevent the formation of the colour due to iron, thioglycollic acid being the more effective. As the solubility of the lake increases with increasing alkalinity the ph in the alkaline method is carefully controlled at 7.5 ± 0.2 by means of ammonium borate solution. Other factors influencing colour development are discussed. The limits of tolerance of elements that interfere in colour production are given, and the application of the methods to the determination of aluminium in soil extracts, soils and clays is described.
The component fatty acids of various sudan vegetable oils
Authors: Grindley D. N.
Published: November 2006

In this paper are recorded the composition of the fatty acids present in the fats from the following materials: Hyptis spicigera, Luffa cylindrica, Lagenaria vulgaris, Citrullus vulgaris (var. inedible melon), Courbonia virgata (Husks and kernels), Capparis tomentosa (kernels), and Parinarimn curatellifolia.

During the past two years, the component acids present in a number of vegetable fats from seeds grown in the Sudan have been determined in these Laboratories, but none of the results seemed of sufficient importance to demand separate publication. In order that our findings may be placed on record, therefore, a summary of these miscellaneous data is offered in this paper.
The use of ion‐exchange resins for the isolation of glutamine and other nitrogenous substances from beetroot
Authors: Westall R. G.
Published: November 2006

The method for the isolation of amino‐acids and organic bases by displacement chromatography using synthetic ion‐exchange resins1, 2 has been employed for fractionating the nitrogenous bases in a beetroot extract. Pure glutamine has been isolated from selected fractions and treatment of other fractions has led to the isolation of betaine and γ‐aminobutyric acid.
A method for separating the constituents of chestnut tannin
Authors: Clark L. M. , Levy W. J.
Published: November 2006

In the course of work in this laboratory it was desired to separate the constituents of a comercmial sample of chestnut tannin. A method of effecting at least a partial separation is described; it appears that this may be more generally useful in tannin fractionations as it is also applicable to oak and quebracho tannins.

When an aqueous solution of chestnut tannin is passed through an absorbing column of wood cellulose powder (Solka Floc), and the column is subsequently developed with a 4% solution of sodium chloride, at least six different bands show up; the fractions represented by these bands have been collected and show different properties. The fractions are not pure, but refractionation of one of the major bands demonstrates that further purification is easily achieved.
Fumigation of agricultural products. II.—Susceptibility of seed potatoes to the vapour of methyl bromide
Authors: Lubatti O. F. , Blackith R. E.
Published: November 2006

The susceptibility of potato tubers to methyl bromide vapour has been measured by two criteria of damage: the loss of tubers rejected before setting and the reduction of yield per viable tuber. Varietal differences are more clearly shown by the latter criterion, as expected, and less clearly by the former. The damage caused by raising the dosage above a critical level has on the contrary much less influence on the yield per viable tuber than on the loss by rotting in storage. This critical level fluctuates widely, probably seasonally. Tubers fumigated in the autumn are enabled to reverse much of the phytotoxic action of the fumigant and losses are much less severe than if the fumigation takes place in the spring immediately before planting.
Arsenical contamination of chicory during drying
Authors: Atkinson R. M. , Dickinson D. , Harris F. J. T.
Published: November 2006

The presence of arsenic in materials dried over coke fires is quite well known. It is shown that chicory dried in England is no exception to this and that arsenic is transferred from the coke to the chicory. Most of the arsenic appears to be present on dried chicory in the form of dust but it cannot be said definitely that this dust is entirely flue dust. Both the volatile and nonvolatile arsenic contents of coke must be taken into consideration. The fate of the arsenic on the dried chicory during subsequent processing has been investigated. It is concluded that the arsenical contamination of dried chicory does not present any considerable risk to the consumer of chicory.
Leather bates from fish‐viscera
Authors: Cunningham G. E. , Shuttleworth Ronald G.
Published: November 2006

Present economic trends suggest that hog‐ and cattle‐pancreas as a source of tryptic enzymes for the manufacture of leather bates may become scarce in the future. An investigation has therefore been conducted on the waste visceral residues' from certain suitable fish obtainable in South African waters (snoek, kingklip and stockfish) with the object of developing a cheap alternative source of bating enzymes. The preparation of a wood‐meal enzyme from the gut of such fish is described and shown to be practicable.

A new technique is described for assessing the relative bating power of commercial and experimental bates, based on changes in thickness and weight of the pelt pieces and practical assessment of the bated pelt. The use of statistical methods of experimental design permits of comparison between the experimental preparations and a typical commercial bating material as well as a control treatment involving no enzyme. It has been shown that under practical bating conditions there is no difference in bating action between the experimental material and the commercial sample when the initial concentrations are adjusted to give equivalent gelatin‐liquefying potency and the same relative proportion of ammonium salts is present.
The component acids of some authentic and commercial stillingia oils
Authors: Crossley A. , Hilditch T. P.
Published: November 2006

Stillingia oils from three specimens of seeds of Sapium sebiferum and from two specimens of seeds of S. discolor have been examined and the composition of their fatty acids determined. The component acids include about 5% of deca‐2 : 4‐dienoic acid, 8% of oleic and 12% of saturated acid, with about 75% of linoleic and linolenic acids as the major components. The proportions of the latter acids vary both with the species and, in the same species, with seasonal conditions : linolenic acid ranges from about 50% to 35%. and linoleic from about 25% to 40%. The oils from S. discolor also contain up to 1% of elaeostearic acid, which has not‐been found in any of the oils from S. sebiferum.

A further specirrlen of commercial stillingia oil has also been examined, and again found to contain about 1% of elaeostearic acid. Since the commercial oil is believed to originate from S. sebiferum, slight contamination with tung oil may be the source of the elaeostearic acid which has now been frequently observed in commercial stillingia oils.
The setting temperature of pectin jellies
Authors: Hinton C. L.
Published: November 2006

The setting temperature of a pectin jelly is shown to be a determinate physical property, whereas the setting time is a secondary property dependent on temperature conditions. A technique for measuring setting temperature is described. As ordinarily manifested the setting temperature is subject to undercooling effects. It is shown that, as with jelly strength, PH conditions are a primary factor in regard to setting temperature, increase of PH causing a rapid fall of the latter; and that soluble solids concentration, pectin concentration, nature of buffer cations and heating have subsidiary effects. The setting temperature does not appear to be related to the jelly strength in any direct way, as judged by a comparison of the effects of the factors studied on the two properties.
Use of Aspergillus niger for determining magnesium, copper, zinc and molybdenum in soils
Authors: Nicholas D. J. D.
Published: November 2006

The use of Aspergillus niger (Mulder's M strain) as a test organism for determining Mg, Cu, Zn and Mo in soils, and the last‐named in tissue extracts and the ash of plants, is described. Special chemical methods are used to remove the ‘test’ nutrient from the basal culture solution. A standard growth series is prepared for each element in turn by adding increasing amounts of the ‘test’ nutrient to 50 ml. portions of the purified basal culture solution containing all the other essential elements at adequate levels. After sterilization, the solution is inoculated with a spore suspension of Aspergillus niger and then incubated at 25° C. for 6 days. The material for test is put into a culture solution containing all the essential mineral elements other than the one to be determined, so that under condition of test, the growth of the fungus depends on the amount of ‘test’ nutrient it derives from the material added.

The bioassay results for soil samples have shown Mg deficiency in the presence of a shortage of K, a point not shown by the chemical analysis of the crops : Cu deficiency in certain alkaline fen soils and in sandy soils where fruit trees showed ‘dieback’ symptoms; Zn deficiency in soil where apple and pear trees showed ‘little leaf ’ symptoms; Mo deficiency in soils from areas where brassica crops showed ‘whiptail’ effects. Because of the extreme sensitivity of the biological method for Mo, it has been used to determine the element in tissue extracts and ash of normal plants and those deficient in molybdenum. Some aspects of the physiology of micronutrient elements in relation to nitrogen metabolism of the fungus are discussed.
Spontaneous heating and ignition in stored palm kernels. I.—A survey of occurrences of heating and fire
Authors: Bowes P. C. , Burgoyne J. H. , Hilditch T. P. , Thomas A.
Published: November 2006

Fifty‐seven occurrences of heating or fire in stored palm kernels have been recorded and analysed. With the exception of one incident in which the heating of kernels in a storage bin occurred, all cases were concerned with kernels in jute bags.

The ignition of a palm‐kernel stack by a small source and the subsequent growth of the fire are discussed in the light of experiments and of the examination of stacks affected by fire. The majority of the fires occurred in one of two sets of circumstances: (i) shortly after discharge from the ship (transit fires); (ii) after storage of at least two months (storage fires). It is concluded that heating due to fermentation takes place in palm‐kernel stacks; but there is also evidence that spontaneous ignition is the cause of some storage fires. It remains to be determined whether spontaneous ignition is necessarily dependent on heating due to fermentation. The evidence as to transit fires is less clear but suggests that a spontaneous effect may be concerned here also. As a result of the survey certain indications can be given as to the experiments needed to decide the mechanism of spontaneous ignition of bagged palm kernels.
Photo‐decomposition of rotenone in spray deposits. I.—Colorimetric determination of rotenone in spray deposits and residues
Authors: Rao N. V. Subba , Pollard A. G.
Published: November 2006

The Goodhue method is adapted to estimate rotenone in concentrations varying between 0.01 and 0.10 mg./c.c. The influence of spray auxiliaries and of dehydrorotenone, the primary decomposition product of rotenone, has been investigated. A method for determination of rotenone in the presence of dehydrorotenone is developed for application to the examination of spray deposits and residues.
Starches and starch fractions. IV.—The hydrolysis of starch to dextrose by hydrochloric acid
Authors: Lampitt L. H. , Fuller C. H. F. , Goldenberg N. , Vine M.
Published: November 2006

The conditions usually employed for the determination of starch by hydrolysis to dextrose with hydrochloric acid all lead to a low recovery of starch, because (a) the hydrolysis of the starch is incomplete and (b) dextrose is destroyed by the acid.
The component fatty acids and glycerides of groundnut oils
Authors: Crawford R. V. , Hilditch T. P.
Published: November 2006

The component acids of four groundnut oils of differing iodine value (86 to 99) have been determined. The linoleic acid content of the mixed fatty acids varied from 20% to 38%, the oleic acid content correspondingly ranging from 60% to 39%. These variations are similar to those recorded by previous workers for groundnut oils, but their cause is not clear and varietal influences as well as conditions of growth of the fruit may play a part in the case of groundnuts.

The variable linoleic acid content has a marked influence on the component glycerides of the oils. Thus with only 20% of linoleic acid a groundnut oil contains linoleo groups in only about half of its glycerides and dilinoleo‐glycerides occur only in small proportions; but in oils of high linoleic content about 90% of the glycerides may contain linoleo groups (20% of the oil being made up of dilinoleo‐glycerides). Moreover, triunsaturated glycerides in the first case contain very little oleodilinolein, but the latter forms about half of the triunsaturated glycerides of groundnut oils with 35–40% of linoleic acid.

The probable bearing of these factors on liability to oxidative rancidity is considered. Attention to the composition of seed oils intended for specific technical uses, as a primary consideration in the selection of oilseeds for cultivation, is indicated.
The fiske‐subbarow method for determining phosphate with special reference to soil extracts
Authors: Yuen S. H. , Pollard A. G.
Published: November 2006

Modifications of the Fiske‐Subbarow method are described by which susceptibility to interference by silicate, arsenate, and certain acids and salts was reduced. In view of the possibility that some soils may contain considerable amounts of extractable arsenate and ferric iron, a method for eliminating interference by these two ions, by reduction with metabisulphite, is described. By this procedure, arsenate and ferric iron up to 20 p.p.m. As2O5 and 80 p.p.m. Fe had no effects on the determination.

The applicability of the modified technique to the determination of phosphate in soil extracts and in plant ashes is examined.
Spontaneous heating and ignition in stored palm kernels. IV.—Observations of temperature, humidity, and air composition in palm‐kernel stacks
Authors: Bowes P. C. , Thomas A.
Published: November 2006

Measurements of temperature and humidity have been made in a steel‐sheeted stack of bagged palm kernels during a period of one year and they have been correlated with the atmospheric temperature and humidity. The oxygen and carbon dioxide contents of the air in the stack have also been determined at intervals.

The results are consistent with the occurrence of ventilation in the stack. This ventilation is apparently sufficient to carry away heat produced by the slow absorption of oxygen which takes place.

Over long periods the mean relative humidity of the air in the stack is about equal to the mean atmospheric humidity for the period, when allowance is made for the difference in temperature that may exist between the interior of the stack and the atmosphere. Thus the overall moisture content of the stack approaches equilibrium with long‐period mean atmospheric humidities; but this is a slow process and the importance of including only dry bags of kernels in the stack is emphasized.

No heating was detected in the stacks under observation and, during those periods when humidity measurements were made, conditions in the stacks were not favourable to active mould‐growth.
The chrysanthemumcarboxylic acids I.—Preparation of the chrysanthemic acids
Authors: Harper S. H. , Reed H. W. B. , Thompson R. A.
Published: November 2006

The large‐scale laboratory preparation of (±)‐cis‐ and (±)‐trans‐chrysanthemic [2: 2‐dimethyl‐3‐isobutenylcyclopropane‐I‐carboxylic] acids is improved, in view of their importance as components of synthetic pyrethrins, e.g. allethrin.

A short series of esters from (±)‐cis‐ and (±)‐trans‐chrysanthemic acids containing either —[CH2]n.C6H4CI‐p, where n = o, 1, and 2, or —CH2.CO.C6H4C1‐p, or —CH2.CC13 groups as the alcoholic components is prepared, representing DDT‐pyrethrin hybrids. Insecticidal testing shows these esters to be substantially non‐toxic to houseflies.
Amino‐acids in the proteins of herbage
Authors: Armstrong R. H.
Published: November 2006

The tryptophan, tyrosine, methionine, cystine and lysine contents of the proteins of 15 herbage species, together with some histidine values, have been determined by microbiological assay, and the difficulties associated with the hydrolysis of protein in the presence of carbohydrate and lipoid materials are discussed.

The values found for tryptophan, tyrosine, methionine and lysine are slightly lower than those obtained by other workers for the analysis of leaf‐protein preparations. The low figures obtained for cystine are almost certainly due to its destruction during the preparation of the hydrolysates. It is suggested that there may be a wider variation in the amino‐acid make‐up of herbage species than has been previously observed.
Some biochemical aspects of bracken ‘POISONING’ in the ruminant animal. I.—Vitamin factors
Authors: Moon F. E. , Raafat M. A.
Published: November 2006

An examination has been made of the significance of several vitamin factors in the production of bracken ‘poisoning’ in ruminants. Bracken feeding led to a rapid cessation of urinary vitamin‐B1 excretion but this was not associated with any consistent increase in pyruvic acid excretion or in blood pyruvic acid concentration. Injections of vitamin B1 given to ruminants showing symptoms of bracken ‘poisoning’ did not produce any recovery. Although bracken‐fed ruminants probably have a subnormal vitamin‐B1 status, no evidence was obtained of any acute deficiency.

Measurements of blood prothrombin time suggested that no deficiency of vitamin K is involved in the production of this disease, but low body‐reserves of vitamins A and C were found in experimental sheep which had died with bracken ‘poisoning’.
The fatty acids and glycerides of an indian sesame oil
Authors: Chakrabarty M. M. , Hilditch T. P.
Published: November 2006

The component acids and glycerides in sesame oil (iodine value 114.1) extracted from seed grown in Eastern India have been investigated. The acids included palmitic 9.4, stearic 5.7, arachidic 1.2, oleic 35.0 and linoleic 48.4% (wt.). The glycerides follow the usual seed‐fat distribution: the chief members present are oleodilinoleins (40%), saturated‐oleo‐linoleins (37%) and dioleolinoleins (15%). 43% of the glycerides contain two linoleic groups and 53% contain one linoleic group per triglyceride molecule.

The glyceride structure of groundnut, cottonseed, sesame, sunflower seed and soya‐bean oils are compared, with special reference to their respective dilinoleo‐ and monolinoleo‐glycerides.
The availability of soil phosphate. III.—The phosphate‐fixing capacity of soil
Authors: Yuen S. H. , Pollard A. G.
Published: November 2006

A method for measuring the phosphate fixation of soil is described, in which the soil‐phosphate mixture is evaporated to dryness and the unfixed phosphate subsequently extracted, using the Morgan reagent.

In long‐term fertilizer experiments, ammonium sulphate decidedly increased the phosphate‐fixing capacity of soil. The effect of different forms of nitrogen on fixation was observed in laboratory experiments, those decreasing the pH causing increase in the fixing capacity of soil. Superphosphate reduced the fixing capacity of soil, probably through its partial saturation of the positive residual valencies of the clay complex. Potassium sulphate did not alter the phosphate‐fixing capacity of soil. Lime precipitated the added phosphate in less soluble forms and thus reduced the fixing capacity of the soil.

Dung caused a marked reduction in phosphate‐fixing capacity, this effect being enhanced by application of lime. The existence of an H2PO4−‐Ca‐humic acid‐micelle linkage would explain the phenomena.

Addition of iron oxide (hydrated) greatly increased the phosphate‐fixing capacity of soil. Addition of acid increased it and that of alkali reduced it, both in the absence and presence of added iron oxide. By removing free iron oxide, the fixing capacity of soil was not reduced and in some cases was further increased, suggesting that free iron oxide in soil was not the main constituent responsible for the fixation.

The relative effects of exchangeable bases on the fixation of phosphate were, in decreasing order, H, K, Na, Mg, Ca. The present work supported the theory of an H2PO4−‐Ca‐micelle in soil.
Soil sterilization. I.—Ammonia and nitrate production in some glasshouse soils following steam sterilization
Authors: Davies J. N. , Owen O.
Published: November 2006

Ammonia production and subsequent nitrate formation have been followed in several types of glasshouse soils after partial sterilization by steam. If soil is steamed in situ and left undisturbed ammonia production continues for a considerable time and nitrate formation is negligible, despite the fact that the soil is open to any aerial and other fortuitous infections. If the same soil is incubated in bulk after steaming and disturbed periodically by sampling, ammonia concentration falls comparatively quickly and nitrification proceeds rapidly. This method of sampling apparently stimulates nitrification and has the same effect as deliberate contamination of the steamed soil by unsteamed soil. Results are adduced to show that a second or subsequent steaming is not so effective as the first one in stimulating ammonia production. There is some evidence that increase in ammonia production is accompanied by a reduction in the nitrate concentration at the same time.
Oxidation in apple juice. II.—Some observations on deaeration
Authors: Marshall C. R.
Published: November 2006

Removal of dissolved oxygen from apple juice in a laboratory deaeration‐apparatus has been studied. The efficiency of the deaerator for removing dissolved oxygen from cold water was found to vary with the initial oxygen content and history of the sample, and did not exceed 76%. The efficiency was raised to well over 80% by multiple‐stage deaeration, and to over 96% by single‐stage deaeration at temperatures of 120° F. or over.

Oxygen removed from apple juice in the same apparatus was poor. Three‐stage deaeration at temperatures of 180° F. was required to attain 89% efficiency on fresh juice, whereas tank‐stored juice under similar conditions lost less than 40% of its oxygen. Oxygen dissolved in apple juice is believed to exist in both ‘free’ and ‘bound’ states, the proportion of ‘bound’ to ‘free’ increasing with length of storage. Only the ‘free’ oxygen is removed completely by deaeration.