An objective analysis of quality and readability of online information on COVID-19

High quality, readable health information is vital to mitigate the impact of the COVID-19 pandemic. The aim of this study was to assess the quality and readability of online COVID-19 information using 6 validated tools. This is a cross-sectional study. "COVID-19" was searched across the three most popular English language search engines. Quality was evaluated using the DISCERN score, Journal of the American Medical Association benchmark criteria and Health On the Net Foundation Code of Conduct. Readability was assessed using the Flesch Reading Ease Score, Flesch-Kincaid Grade Level and Gunning-Fog Index. 41 websites were suitable for analysis. 9.8% fulfilled all JAMA criteria. Only one website was HONCode certified. Mean DISCERN score was 47.8/80 ("fair"). This was highest in websites published by a professional society/medical journal/healthcare provider. Readability varied from an 8th to 12th grade level. The overall quality of online COVID-19 information was "fair". Much of this information was above the recommended 5th to 6th grade level, impeding access for many.

Awareness and knowledge of Human papillomavirus (HPV) among ethnically diverse women varying in generation status

Although Human papillomavirus (HPV) is a common sexually transmitted infection, there is limited knowledge of HPV with ethnic/racial minorities experiencing the greatest disparities. This cross-sectional study used the most recent available data from the California Health Interview Survey to assess disparities in awareness and knowledge of HPV among ethnically/racially diverse women varying in generation status (N = 19,928). Generation status emerged as a significant predictor of HPV awareness across ethnic/racial groups, with 1st generation Asian-Americans and 1st and 2nd generation Latinas reporting the least awareness when compared to same-generation White counterparts. Also, generation status was a significant predictor of HPV knowledge, but only for Asian-Americans. Regardless of ethnicity/race, 1st generation women reported lowest HPV knowledge when compared to 2nd and 3rd generation women. These findings underscore the importance of looking at differences within and across ethnic/racial groups to identify sub-groups at greatest risk for poor health outcomes. In particular, we found generation status to be an important yet often overlooked factor in the identification of health disparities.

Continuous hyperfractionated accelerated radiotherapy - Escalated dose (CHART-ED): A phase I study

INTRODUCTION

Patients who present with locally advanced inoperable non-small cell lung cancer (NSCLC) may be suitable for radical radiotherapy. A randomised trial of 563 patients compared CHART and conventional radical radiotherapy (60 Gy/30f) given over 6 weeks and suggested that CHART resulted in a 9% improvement in 2-year survival (Saunders et al., 1999). RT dose escalation for both conventional and CHARTWEL (CHART-WeekEndLess) - fractionation schedules is feasible with modern 3-dimensional CT-based planning techniques and we initiated a phase I CHART dose escalation study in 2009.

METHODS

Patients with WHO performance status 0-2 histologically confirmed, inoperable, stage I-III non-small cell lung cancer were recruited into an open phase I dose escalation trial. Three cohorts of six patients were recruited sequentially. Total dose was escalated from standard CHART radiotherapy of 54 Gy/36f/12 days to 57.6G y (2 × 1.8 Gy fractions on day 15, Group 1), 61.2 Gy (4 × 1.8 Gy fractions on days 15-16, Group 2) and 64.8 Gy (6 × 1.8 Gy fractions on days 15-17, Group 3).

RESULTS

Between April 2010 and May 2012, 18 patients were enrolled from 5 UK centres and received escalated dose radiotherapy. 14 were male, 16 squamous cell histology and 12 were stage IIIA or IIIB. The median age was 70 years and baseline characteristics were similar across the three dose cohorts. One patient did not start escalated radiotherapy but all remaining patients completed their planned radiotherapy schedules. Of these 9 patients have died to date with a median survival of 2 years across the three cohorts. Grade 3 or 4 adverse events (fatigue, dysphagia, nausea and anorexia - classified according to the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 4.0) were reported in 6 patients but the pre-specified dose limiting toxicities (grade 4 early oesophagitis; grade 3 cardiac, spinal cord and pneumonitis) were not observed.

CONCLUSIONS

CHART remains a radiotherapy schedule in routine use across the UK and in this dose escalation study no dose limiting toxicities were observed. We feel the dose of 64.8 Gy/42f/17 days should be taken forward into further clinical trials. The sample size used in this study was small so we plan a randomised phase II study that includes other radiotherapy schedules to confirm safety and select an accelerated sequential chemo-radiotherapy schedule to take into phase III studies.

The reaction of methyl sterculate and malvalate with silver nitrate-silica gel and its use as a basis for the estimation of cyclopropene fatty acids

When in contact with silver nitratesilica gel, methyl esters of cyclopropene fatty acids undergo ring opening to yield pairs of isomers with methylene, hydroxymethyl, or nitratomethyl side-chains at the original ring positions. Thus the main products from methyl sterculate were the methyl 9 (or 10)-methylene octadec-10 (or 8)-enoates, and, in lesser quantities, the methyl 9 (or 10)-(nitratomethyl)-octadec-9-enoates and the methyl 9 (or 10)-(hydroxymethyl)-octadec-9-enoates. Hydrogenation quantitatively converted this mixture of isomeric pairs to a mixture of methyl 9- and methyl 10-methyloctadecanoates.Chromatography on silver nitrate-silica gel, followed by gas chromatography of the hydrogenated products, has been used as the basis of a new method for estimating individual cyclopropene and cyclopropane acids in lipids.

Phenformin as prophylaxis and therapy in breast cancer xenografts

BACKGROUND

Observations that diabetics treated with biguanide drugs have a reduced risk of developing cancer have prompted an enthusiasm for these agents as anti-cancer therapies. We sought to determine the efficacy of the biguanide phenformin in the chemoprophylaxis and in the treatment of oestrogen receptor (ER)-positive MCF7 and receptor triple-negative MDAMB231 xenografts in immunocompromised mice. We also compared the efficacy of phenformin and metformin in the treatment of MDAMB231.

METHODS

Immunocompromised mice were divided into groups: (1) phenformin administered for 2 weeks prior to cell injection; (2) established tumours treated with phenformin; (3) established tumours treated with metformin (only for MDAMB231 tumours); (4) untreated controls. Post-treatment tumours, liver and spleen were harvested for further analysis.

RESULTS

Phenformin significantly inhibited both the development and growth of MCF7 and MDAMB231 tumours, and for MDAMB231 at greater efficacy than metformin without murine toxicity. The number of mitotic figures was significantly fewer in xenografts treated with phenformin compared with controls. Results suggested that the mechanism of action of phenformin in vivo is consistent with AMPK activation.

CONCLUSION

Phenformin has clinical potential as an antineoplastic agent and should be considered for clinical trials both in ER-positive and triple-negative breast cancer.

Abstract P1-03-07: Differential Effect of Specific p53 Mutations on Breast Cancer Growth and Response to Hsp90 Inhibition In Vivo

Background p53 mutation influences breast cancer cell growth and patient prognosis. However, different p53 mutations impart specific functions to the mutant protein, including dominant negative or gain of function effects. Mutant p53 molecules R273H and R175H are commonly found in primary breast cancers and are present in the MDA-MB-468 and SKBR3 cell lines, respectively. To compare the direct effects of these two mutations in vivo in an identical cellular background, H1299 (p53-null) cells were constructed to express R273H or R175H p53 mutants. Methods

Thirty female SCID mice were injected subcutaneously with 106 H1299 (p53-null), H1299/R273H or H1299/R175H cells in DMEM + Matrigel (50:50) suspension. Some mice were treated with an Hsp90 inhibitor, which is required for correct folding of many oncogenic proteins. Results

Xenografts bearing R175H showed a mean lag phase (time between cell injection and tumors at exponential growth) of 21 days and a doubling time of 5 days, whereas tumors bearing H1299 (p53-null) or R273H mutation had a lag phase of 31 days with a doubling time of 7 days. Immunohistochemical examination demonstrated a highly heterogeneous pattern of p53 protein expression in the more aggressive R175H expressing cells compared with R273H expressing cells. Hsp90 inhibitor treatment reduced the growth of H1299 and R273H cells, but not R175H cells. Conclusions

The specific p53 mutations directly influence the rate of tumor growth and the p53 protein staining pattern on immunohistochemistry. The differential effects of specific p53 mutations should be considered when interpreting clinical data involving p53 mutation such as in the EORTC 10994 trial, with implications for prognostic determination of individual breast cancer patients.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-03-07.

Sorption behavior of a synthetic antioxidant, polycyclic musk, and an organophosphate insecticide in wastewater sludge

Emerging contaminants (ECs) are chemicals that are currently unregulated due to limited understanding of health effects and limited data regarding occurrence. Wastewater treatment plants (WWTP) receive many ECs as components of influent waste and the removal of organic contaminants, such as ECs, occurs primarily by sorption to sludge. Therefore, it is important to develop measures of sorption behavior by ECs to sludge. This study evaluates sorption of three ECs: 3-tert-butyl-4-hydroxyanisole (BHA) a synthetic antioxidant, 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta(g)-2-benzopyrane (HHCB) a polycyclic musk, and chlorpyrifos a organophosphate insecticide. Twenty-four hour laboratory-scale sorption experiments were conducted for each compound individually and then in combination, which allowed the quantification of sorption onto wastewater sludge and the affects of multiple compounds. ECs in both the liquid and solid phases were analyzed using a gas chromatograph with flame ionization detector (GC/FID). Isotherms of individual sorption behavior followed a linear trend (R2 > 0.9) for individual ECs, while K(d) averaged 2,689 L kg(-1), 27,786 L kg(-1) and 31,402 L kg(-1) for BHA, chlorpyrifos and HHCB, respectively. Sorption behavior for BHA was linear during combined studies with K(d) of 1,766 L kg(-1) or a decrease of 34%, while HHCB and chlorpyrifos followed non-linear isotherm models. Synergistic effects were observed with spike concentrations > or =25 mg L(-1) for HHCB and > or =20 mg L(-1) for chlorpyrifos. K(d) values ranged from 16,984-6,000,000 L kg(-1) for HHCB and 19,536-3,000,000 L kg(-1) for chlorpyrifos. These distribution coefficients differed substantially from previously published values, mainly because few studies used sludge as the sorption media. Results suggest that HHCB and chlorpyrifos may be contained in the sludge unlike BHA, which is more available in the aqueous phase. Future investigations should evaluate WWTP processes for degrading ECs to harmless products and releases of ECs from sludge.

Poliovirus 5'-terminal cloverleaf RNA is required in cis for VPg uridylylation and the initiation of negative-strand RNA synthesis

Chimeric poliovirus RNAs, possessing the 5' nontranslated region (NTR) of hepatitis C virus in place of the 5' NTR of poliovirus, were used to examine the role of the poliovirus 5' NTR in viral replication. The chimeric viral RNAs were incubated in cell-free reaction mixtures capable of supporting the sequential translation and replication of poliovirus RNA. Using preinitiation RNA replication complexes formed in these reactions, we demonstrated that the 3' NTR of poliovirus RNA was insufficient, by itself, to recruit the viral replication proteins required for negative-strand RNA synthesis. The 5'-terminal cloverleaf of poliovirus RNA was required in cis to form functional preinitiation RNA replication complexes capable of uridylylating VPg and initiating the synthesis of negative-strand RNA. These results are consistent with a model in which the 5'-terminal cloverleaf and 3' NTRs of poliovirus RNA interact via temporally dynamic ribonucleoprotein complexes to coordinately mediate and regulate the sequential translation and replication of poliovirus RNA.

Poly(rC) binding proteins mediate poliovirus mRNA stability

The 5'-terminal 88 nt of poliovirus RNA fold into a cloverleaf RNA structure and form ribonucleoprotein complexes with poly(rC) binding proteins (PCBPs; AV Gamarnik, R Andino, RNA, 1997, 3:882-892; TB Parsley, JS Towner, LB Blyn, E Ehrenfeld, BL Semler, RNA, 1997, 3:1124-1134). To determine the functional role of these ribonucleoprotein complexes in poliovirus replication, HeLa S10 translation-replication reactions were used to quantitatively assay poliovirus mRNA stability, poliovirus mRNA translation, and poliovirus negative-strand RNA synthesis. Ribohomopoly(C) RNA competitor rendered wild-type poliovirus mRNA unstable in these reactions. A 5'-terminal 7-methylguanosine cap prevented the degradation of wild-type poliovirus mRNA in the presence of ribohomopoly(C) competitor. Ribohomopoly(A), -(G), and -(U) did not adversely affect poliovirus mRNA stability. Ribohomopoly(C) competitor RNA inhibited the translation of poliovirus mRNA but did not inhibit poliovirus negative-strand RNA synthesis when poliovirus replication proteins were provided in trans using a chimeric helper mRNA possessing the hepatitis C virus IRES. A C24A mutation prevented UV crosslinking of PCBPs to 5' cloverleaf RNA and rendered poliovirus mRNA unstable. A 5'-terminal 7-methylguanosine cap blocked the degradation of C24A mutant poliovirus mRNA. The C24A mutation did not inhibit the translation of poliovirus mRNA nor diminish viral negative-strand RNA synthesis relative to wild-type RNA. These data support the conclusion that poly(rC) binding protein(s) mediate the stability of poliovirus mRNA by binding to the 5'-terminal cloverleaf structure of poliovirus mRNA. Because of the general conservation of 5' cloverleaf RNA sequences among picornaviruses, including C24 in loop b of the cloverleaf, we suggest that viral mRNA stability of polioviruses, coxsackieviruses, echoviruses, and rhinoviruses is mediated by interactions between PCBPs and 5' cloverleaf RNA.

TPO1, a member of a novel protein family, is developmentally regulated in cultured oligodendrocytes

Although the myelin membrane contains only a small set of major proteins, more sensitive assays indicate the presence of a plethora of uncharacterized proteins. We have used an antibody perturbation approach to reversibly block the differentiation of prooligodendroblasts into myelinating cells, and, in combination with a differential screening procedure, identified novel mRNAs that are activated during this period. One cDNA, TPO1, recognizes a 5.5-kb mRNA that is strongly up-regulated in oligodendrocytes after release of the differentiation block and that is expressed at high levels in brain tissue during active myelination. This cDNA represents at least two mRNAs differing from each other in their 5'-termini. The TPO1 cDNA contains an open reading frame of 1,380 bp, encoding a protein of 51.8 kDa with a predicted pI of 9.1 that contains two regions homologous to nonclassic zinc finger motifs. Subcellular localization studies suggest the enriched presence of TPO1 in spherical structures along the major cytoplasmic processes of oligodendrocytes. TPO1, along with homologues expressed in testis, placenta, and PC12 cells, form a novel family of proteins with multiple hydrophobic domains possibly serving as membrane spanning regions. We postulate that in oligodendrocytes, TPO1 encodes a protein factor involved in myelin biogenesis.

Flash-lamp-pumped Ho:Tm:Cr:YAG and Ho:Tm:Er:YLF lasers: modeling of a single, long pulse length comparison

Two methods of producing the long pulse lengths that promote efficient extraction of energy from low-gain, quasi-four-level lasers are analyzed. A long pulse length output can mitigate laser-induced damage effects and can be generated in quasi-four-level lasers by two disparate methods. One method utilizes Q-switching techniques in resonators designed to extend the pulse length and another utilizes the first pulse in a relaxation oscillation pulse train. Models for quasi-four-level lasers are derived here taking into account the nonnegligible thermal population of the lower laser level. Closed-form expressions are derived for both modes of operation of quasi-four-level laser systems so the parametric dependencies of both forms of operation become obvious, allowing facile comparison. In addition, a combined absorption and quantum efficiency, germane for flash-lamp pumping, is calculated for both Cr and Er sensitizers. Although the former has the advantage of broad absorption bands, the latter has the advantage of a quantum efficiency approaching 3.

Flash-lamp-pumped Ho:Tm:Cr:YAG and Ho:Tm:Er:YLF lasers: experimental results of a single, long pulse length comparison

Flash-lamp-pumped, room-temperature Ho:Tm:Cr:YAG and Ho:Tm:Er:YLF are compared for single but long pulse operation, with pulse lengths of approximately 1.0 mus. Under similar operating conditions in normal-mode operation, a slope efficiency of 0.0331 was observed for Ho:Tm:Er:YLF compared with 0.0047 for Ho:Tm:Cr:YAG. For Q-switched operation, Ho:Tm:Er:YLF yielded a slope efficiency of 0.0075. In comparison, a slope efficiency of 0.0012 was obtained for Ho:Tm:Cr:YAG. Two methods of producing long pulse lengths are compared: pulse selection of normal-mode relaxation oscillations and Q-switching in a long resonator. Theoretical models developed in a companion paper for normal-mode relaxation oscillations and Q-switching in quasi-four-level solid-state lasers are in agreement with the experimental results.

Diode-pumped long-pulse-length Ho:Tm:YLiF(4) laser at 10 Hz

An optical efficiency of 0.052 under normal mode operation for diode-pumped Ho:Tm:YLiF(4) at a pulse repetition frequency of 10 Hz has been achieved. Laser output energy of 30 mJ in single Q-switched pulses with 600-ns pulse length were obtained for an input energy of 3 J. A diffusion-bonded birefringent laser rod consisting of Ho:Tm-doped and undoped pieces of YLF was utilized for 10-Hz operation.

Presence of N-acyl and acetoxy derivatives of putrescine and cadaverine in the human gut

N-acyl and acetoxy derivatives of putrescine and cadaverine have been found in the faeces of children and in cultures of isolates of gut bacteria. The evidence was accumulated from two dimensional, thin layer chromatography, field desorption mass spectrometry, and accurate mass measurement of the DANS derivatives of the amines. The acetoxy compounds of putrescine and cadaverine have not previously been reported.

Studies of the free faecal amines of infants with gastroenteritis and of healthy infants

The free primary amines present in the faeces of 44 infants (1-18 months) with gastroenteritis have been examined by field desorption mass spectrometry of the lactone form of their fluorescamine derivatives without their prior separation. p-Tyramine, 2-phenylethylamine, the diamines, putrescine and cadaverine and several of their acyl derivatives were common constituents, but a number of other amines were also characterised. Using thin layer chromatography and field desorption mass spectrometry of the amine dansyl derivatives a comparative study was made of the faecal amines of 13 selected infants with gastroenteritis (diarrhoea) and of 13 healthy infants. p-Tyramine, the most abundant amine, was significantly higher (p = 0.02) in the sick infants. The overall presence of p-tyramine was more significantly related to the diet of the infants. Faecal tyramine was low in breast fed infants but significantly higher (p = 0.01) in infants fed cow's milk.

Concentration of headspace, airborne and aqueous volatiles on Chromosorb 105 for examination by gas chromatography and gas chromatography-mass spectrometry

Techniques are described for the collection of volatile material from headspace vapours and the atmosphere and for the direct extraction of volatiles from aqueous solution by traps containing the porous polymer Chromosorb 105. The traps are inserted through a valve into a gas chromatograph which facilitates the desorption and transfer of the volatiles to high-resolution capillary columns. Selected applications of the technique are described.

The chemistry of food flavour. I. Volatile constituents of passionfruit, Passiflora edulis

The volatile constituents of the purple-skinned passionfruit (Passifora edulis Sims) have been investigated. The volatiles were concentrated, fractionated by gas chromatography and chromatography on silica gel, and the resulting fractions examined by combined gas chromatography-mass spectrometry. The majority of the components identified are esters derived largely from combinations of the alkan-1-ols (C1,2,4,6,8) the alkan-2-ols (C5,7),(Z)-and (E)-hex-3-en-1-ol,(2)-hex-4-en-1-ol,and benzyl alcohol, with acids of even carbon number (acetic, butanoic, hexanoic, octanoic, hex-3-enoic, oct-3-enoic, and 3-hydroxyhexanoic). The non-ester constituents include many of the above free alcohols, acetaldehyde, alkan-2-ones (C3,5,7,9,11), monoterpenes ((E)-β-ocimene, 1,8-cineole, linalool, α-terpineol, citronellol, geraniol, citronellyl acetate, (Z) and(E) five-membered ring linalool oxides), and 1,1,6-trimethyl- l,2-dihydronaphthalene, β-ionone, γ-hexanolac-tone, γ-octanolactone, and the lactone of 2-hydroxy-2,6,6-trimethylcyclohexylidene- acetic acid. Preliminary odour assessment of the constituents has indicated that volatile passionfruit flavour is complex. Many components, especially certain esters, are clearly important and one component, not yet completely characterized, may have particular significance.

α-Farnesene: Isolation from the natural coating of apples

The isolation of a pure sesquiterpene hydrocarbon from the natural coating of Granny Smith apples is described. Evidence mainly from its ultraviolet, infrared, mass, and N.M.R. spectra establish it as an α- farnesene stereoisomer (I) with a trans configuration assigned to the 9,10 double bond and a likely trans configuration of the 6,7 bond. Its infrared, mass, and N.M.R. spectra and those of trans-β-farnesene (II) are reported.

Investigations of suint. II. The positive identification of some constituent organic acids

Chiefly by the use of gas chromatography and mass spectrometry the following acids have been positively identified as constituents of the suint from a crossbred Merino fleece: Acetic, propionic, butyric, valeric, hexanoic, isobutyric, 2-methylbutyric, 3-methylbutyric, 2-methylvaleric, succinic, glutaric, α-hydroxyglutaric, α-ketoglutaric, benzoic, and phenylacetic.

Studies in Waxes. XXI. The Branched-chain Acids of the Preen Gland Wax of the Goose

Largely by the use of gas chromatographic techniques the two main constituent acids of the preen gland wax of the goose have been isolated and shown to be 2,4,6,8-tetramethyldecanoic and 2,4,6,8-tetramethylundecanoic acids.

Investigations of Suint. I. The Composition of the Organic Acids from Fleeces of Different Origin

A major part of the organic acids of the suint from each of seven samples of wool fleece of different origin has been examined by gas chromatography of the methyl esters. Twenty-three acids have been identified in one or more of the samples by the retention times of the esters. The composition of all samples was complex and differed considerably both quantitatively and qualitatively.

Studies in Waxes. XVIII. Beeswax: A Spectroscopic and Gas Chromatographic Examination

A quantitative examination has been made of the components of hydrolysed beeswax. This was achieved by separation into hydrocarbons, monohydric alcohols, " diols ",acids, and hydroxyacids. The alcohol and acid fractions were reduced to the corresponding hydrocarbon mixtures and these together with the naturally occurring hydrocarbons were examined by gas chromatography, which demonstrated their straight-chain character and gave the chain lengths and percentage composition of the components.

Studies in Waxes. XX. The Quantitative Analysis of Hydrolysed Carnauba Wax by Gas Chromatography

The hydrolytic products of carnauba wax, previously shown to consist mainly of straight-chain alcohols, α,ω-diols, alkanoic acids, and ω-hydroxyalkanoic acids, have been reexamined by gas chromatographic methods to provide a qualitative and quantitative knowledge of the components. These components, shown to be almost entirely straight chain in character, are largely even carbon numbered compounds, but odd chain-lengths are present. The hydrocarbons are likewise of odd and even carbon number with the odd members (90%) predominating. An unidentified compound, possibly an unsaturated steroid diol, has been isolated from the unsaponifiable fraction.

Studies in Waxes. XIX. The Stem Wax of the Grass Leptochlona digitata

The stem wax of the grass Leptochloa digitata (R.Br.) Domin. has been examined mainly by gas chromatographic methods. The wax after hydrolysis has been shown to consist largely of straight-chain acids (54%) and n-paraffin hydrocarbons (21%). Straight-chain alcohols and ketones are also present, along with other alcohols and ketones which were not examined. A feature of the wax is the presence of small amounts of hydrocarbons with very long chains (2.5%) from which n-dohexacontane (C62H126) has been isolated and identified by its X-ray long spacing and melting point.

Studies in Waxes. XIV. An Investigation of the Aliphatic Constituents of Hydrolysed Wool Wax by Gas Chromatography

A quantitative analysis has been made of the composition of each of the classes of aliphatic constituents known to exist in hydrolysed wool wax. These classes consist of α-hydroxy acids, ω-hydroxy acids, alkanoic acids, monohydric alcohols, and α,β-diols. Each has been found to contain members of the normal, iso-, and anteiso-homologous series of compounds. The analysis was carried out by saponification of the wax and separation of the constituents into the above classes which were separately reduced to the corresponding hydrocarbon mixtures. The composition of these mixtures was determined by gas chromatographic separation.

Sugar-Cane Wax. II. An Examination of the Constituents of Sugar-Cane Cuticle Wax by Gas Chromatography

Sugar-cane cuticle wax previously found to consist of long-chain aldehydes, alcohols, acids, and hydrocarbons (Lamberton and Redcliffe 1960) has been re-examined by gas chromatography to identify and estimate the individual constituents. The aldehydes, alcohols, and acids, all straight chain, are principally of even carbon number in each instance with the C28 member predominant, but appreciable amounts of odd carbon homologues are also present. The hydrocarbons are also of odd and even carbon number but with the odd members in greater amounts and n-heptacosane as the major hydrocarbon constituent.

A Method for the Determination of the Structure of Saturated Branched-Chain Fatty Acids

A method is described for the determination of the structure of branched-chain fatty acids. It is found that the carbon chain of methyl-branched acids can be readily degraded by potassium permanganate in acetone, to give a series of acids of decreasing carbon number. Where a branch occurs the acid series is interrupted and a methyl ketone, of the same carbon number as a missing acid, is produced. Gas chromatographic examination of the ketone(s) and esterified acids gives clear evidence for the location of the branch(es). The method is illustrated by application to tuberculostearic acid (10-methyl-octadecanoic acid) and C27-phthianoic acid (2,4,6-trimethyltetracosanoic acid). It appears also able to decide the location of the ring in cyclopropane fatty acids.

Studies of waxes. X. The diols of carnauba wax

Four α-ω-diols have been isolated from the unsaponifiable fraction of carnauba wax and identified as n-docosane-1,22-diol, n-tetracosane-1,24-diol, n-hexacosane-1,26-diol, and n-octacosane-1,28-diol.

Studies of waxes. XI. The hydroxy acids of carnauba wax

Seven ω-hydroxy acids have been identified as constituents of carnauba wax. They are 18-hydroxyoctadecanoic, 20-hydroxyeicosanoic, 22-hydroxydooosanoic, 24-hydroxytetracosanoic, 26-hydroxyhexacosanoic, 28-hydroxyoctacosanoic, and 30-hydroxytriacontanoic acids.

Studies of Waxes. IX. The normal alcohols of wool wax

Seven normal alcohols have been isolated from the unsaponifiable part of wool wax and identified as n-octadecanol, n-eicosanol, n-docosanol, n-tetracosanol, n-hexacosanol, n-octacosanol, and n-triacontanol.

A Study of the Oxidation of Ethylene to Ethylene Oxide on a Silver Catalyst

A study has been made of the direct oxidation of ethylene to ethylene oxide in a flowing system under the catalytic action of silver. Various catalysts were prepared and one containing 10 per cent. barium carbonate, having a high and sustained activity, was selected for a detailed examination of the influence of reaction conditions on the yield of ethylene oxide. It has been found that the percentage ethylene in the reaction mixture can be varied widely without greatly changing the yield of ethylene oxide, but that the conversion is decreased by increasing the ethylene content. The yield increases with increasing oxygen content until the latter reaches 20 per cent. after which further enrichment with oxygen has little effect. The presence of water vapour slightly increases the yield, hut considerably decreases conversion. The yield is much decreased by diminishing the reaction pressure. Highest yields (73 per cent.) were obtained when small amounts of ethylene dichloride were added to the reactants but at the expense of low conversion. Propylene and isobutylene yielded only carbon dioxide and water when oxidized in the presence of a silver catalyst. The results are discussed in relation to the reaction mechanism suggested by Twigg(1).