bluuebunny/crossref_metadata_2025 huggingface dataset:
La Divine Chanson : les musiques funambules ou Papa Legba aux carrefours des continents
Authors: Delmeule Jean-Christophe
Published: October 2018

Si le continent africain résonne en Amérique, c’est par la voix de Sammy Kamau-Williams, double du poète-musicien Gil Scott-Heron, qui a réellement existé. Le narrateur de La Divine Chanson, un chat nommé Paris, est un autre avatar de son maître. Ce félin roux dessine aussi en creux la silhouette d’Abdourahman A. Waberi, écrivain djiboutien, qui propose ainsi une biofiction inspirée des pratiques musicales noires américaines. Que reste-t-il en effet des empreintes du passé africain dans le présent afro-américain ? Et que peut-on reconstruire sur l’amnésie et la honte ? Des récits féériques, des tentatives de filiations, des projets de Révolution. Mais surtout une musique qui relie le Nord et le Sud, et longe les berges du Mississippi. Le blues envahit ainsi les espaces comme il accompagne les dérives funambules. Le texte, dès lors, politique, essentiellement esthétique, joue de superpositions plurielles, et il inscrit ses propres sillons poétiques dans l’ombre magique d’un dieu béninois devenu loa haïtien, Papa Legba, posté aux carrefours des existences, à la croisée du passé, du présent et de l’avenir.
« Le deuxième livre de l’ethnographe » africaniste : de Michel Leiris à Valentin Yves Mudimbe
Authors: Ndong Ndong Yannick-Martial
Published: October 2018

Pourquoi certains chercheurs africanistes éprouvent-ils lebesoin d’écrire un récit de vie ou un carnet devoyage avant ou après une monographie scientifique soldant uneenquête de terrain ? La première forme aurait-elletout simplement une dimension résiduelle, réduite ainsiau statut d’appendice de la seconde, ou au contraire les deuxseraient-elles complémentaires ? Ces problématiquescouvrent un champ et une période relativement vastes, allant dela pratique de la réflexivité chez les chercheurs ensciences humaines et sociales – Michel Leiris, Georges Balandier,Jean-Loup Amselle – aux continuités et recoupements quel’on observe dans les études littéraires etcritiques – Alain Ricard, Bernard Mouralis, Valentin-YvesMudimbe, Manthia Diawara, etc. C’est pour faire place auxcontinuités plutôt qu’aux ruptures que l’onrelativise la formule de « deuxième livre del’ethnographe », de Vincent Debaene, luipréférant celle du double livre, favorable auxrecoupements entre productions, par-delà les genres.
Mobilités de l’oeuvre : exils, errances et retours
Authors: Mazauric Catherine
Published: October 2018

Dans l’oeuvre d'Henri Lopes, partir, c’est se faire autre : les mobilités spatiales s'y conjuguent à une essentielle plasticité identitaire. À travers des êtres de plusieurs vies et de multiples appartenances en proie à l’« enracinerrance », figures ubiquitaires tout à la fois ancrées « au Pays » et désancrées, l’oeuvre lopésienne ne cesse ainsi de déplacer et fluidifier les catégories à travers lesquelles sont ordinairement inventoriés tant les formes et situations de déplacement (voyage, exil, migration, immigration, errance, retour, etc.) que les lieux entre lesquels elles se jouent, les tonalités affectives qui leur sont associées et les écritures qui en rendent compte. Le paysage intérieur sur fond duquel son oeuvre se déploie, formé des méandres du fleuve, de l’île et de la rive, étant lui-même mobile, elle conjoint le mouvement à une forme de stabilité, l’élan à une possibilité de réassurance constamment maintenue. La séduction qui en émane ne tiendrait-elle finalement pas à sa propension à solliciter les zones intermédiaires du psychisme, celles où s’élaborent les possibles de l’aventure humaine ?
L’histoire et son traitement dans l’oeuvre d’Henri Lopes
Authors: Mouralis Bernard
Published: October 2018

À la différence de Mongo Beti ou de Tchicaya U Tam’si, Henri Lopes, dans ses romans, n’a pas cherché à retracer une histoire avec la périodisation qu’un tel projet implique. Dans un premier temps, on examinera l’intérêt que Lopes porte à l’écriture d’une chronique sociale nettement insérée dans le contexte de l’Afrique des années 1960-1970, avec le recueil de nouvelles Tribaliques (1971), La Nouvelle Romance (1976) et Sans tam-tam (1977). Puis, avec Le Pleurer-rire (1982), il sort du cadre strict de la chronique en proposant, dans la lignée de Rabelais et M.A. Asturias, le portrait d’un dictateur, truculent, cruel, obscène. L’article s’interroge enfin sur la façon dont Lopes ne cesse d’entrelacer l’histoire et l’Histoire, en s’appuyant notamment sur le cas de Marie-Ève, l’héroïne peintre de Sur l’autre rive (1992), et sur des textes plus nettement autobiographiques (Ma grand-mère bantoue et mes ancêtres les Gaulois, 2003) ou relevant de l’autofiction (Le Méridional, 2015).
Henri Lopes, anti-« parrain » de la phratrie congolaise
Authors: Gahungu Céline
Published: October 2018

Entre 1969 et 1980, protecteur politique et modèle littéraire, Henri Lopes se refuse à exercer une autorité charismatique sur les novices de la phratrie. Au fil des entretiens, revient une antienne : il n’est pas un mentor et renvoie volontiers les débutants qui le sollicitent aux Lettres à un jeune poète de Rilke. Susciter « l’envie » de prolonger son oeuvre « insolente », faire de la phratrie un laboratoire créatif destiné aux apprentis et les « aider » à se « sentir écrivains » – ce sont là les seules « leçons » dispensées par le romancier dont les textes réfléchissent, à l’infini, la dynamique exploratoire de son écriture.
Crystal structures of DNA polymerase I capture novel intermediates in the DNA synthesis pathway
Authors: Chim Nicholas , Jackson Lynnette N , Trinh Anh M , Chaput John C
Published: October 2018

High resolution crystal structures of DNA polymerase intermediates are needed to study the mechanism of DNA synthesis in cells. Here we report five crystal structures of DNA polymerase I that capture new conformations for the polymerase translocation and nucleotide pre-insertion steps in the DNA synthesis pathway. We suggest that these new structures, along with previously solved structures, highlight the dynamic nature of the finger subdomain in the enzyme active site.
Distributed Bayesian networks reconstruction on the whole genome scale
Authors: Frolova Alina , Wilczyński Bartek
Published: October 2018

Background

Bayesian networks are directed acyclic graphical models widely used to represent the probabilistic relationships between random variables. They have been applied in various biological contexts, including gene regulatory networks and protein–protein interactions inference. Generally, learning Bayesian networks from experimental data is NP-hard, leading to widespread use of heuristic search methods giving suboptimal results. However, in cases when the acyclicity of the graph can be externally ensured, it is possible to find the optimal network in polynomial time. While our previously developed tool BNFinder implements polynomial time algorithm, reconstructing networks with the large amount of experimental data still leads to computations on single CPU growing exceedingly.

Results

In the present paper we propose parallelized algorithm designed for multi-core and distributed systems and its implementation in the improved version of BNFinder—tool for learning optimal Bayesian networks. The new algorithm has been tested on different simulated and experimental datasets showing that it has much better efficiency of parallelization than the previous version. BNFinder gives comparable results in terms of accuracy with respect to current state-of-the-art inference methods, giving significant advantage in cases when external information such as regulators list or prior edge probability can be introduced, particularly for datasets with static gene expression observations.

Conclusions

We show that the new method can be used to reconstruct networks in the size range of thousands of genes making it practically applicable to whole genome datasets of prokaryotic systems and large components of eukaryotic genomes. Our benchmarking results on realistic datasets indicate that the tool should be useful to a wide audience of researchers interested in discovering dependencies in their large-scale transcriptomic datasets.
Benzylalkohol – Bestimmung von Benzylalkohol in der Luft am Arbeitsplatz mittels Gaschromatographie nach Thermodesorption [Air Monitoring Methods in German language, 2018]
Authors: Tschickardt M. , Krämer W. , Schmitt R. , Hebisch R. , Hartwig A. ,   MAK Commission
Published: October 2018

This analytical method is a validated measurement procedure for the determination of benzyl alcohol [100‐51‐6] in workplace air in a concentration range of one tenth up to twice the currently valid MAK value of 22 mg/m3. With this method simultaneously airborne benzyl alcohol in the gaseous state as well as particles are collected. Sampling is performed by drawing a defined volume of air through a quartz fibre filter located in the sampling head with an adsorption tube filled with Tenax TA connected downstream using a suitable pump. The flow rate is set to 0.066 L/min with a recommended air sample volume of approx. 4 litres. The collected benzyl alcohol is thermally desorbed and then analysed by means of gas chromatography using two detectors, a FID for quantification and a MSD to recognise potential interferences. The quantitative determination is based on a calibration function obtained by means of a multi‐point calibration. The limit of quantification is 0.24 mg/m3based on an air sample of approx. 4 litres.
2‐Phenoxyethanol – Bestimmung von 2‐Phenoxyethanol in der Luft am Arbeitsplatz mittels Gaschromatographie nach Thermodesorption [Air Monitoring Methods in German language, 2018]
Authors: Tschickardt M. , Krämer W. , Schmitt R. , Hebisch R. , Hartwig A. ,   MAK Commission
Published: October 2018

This analytical method is a validated measurement procedure for the determination of 2‐phenoxyethanol [122‐99‐6] in workplace air in a concentration range of one tenth up to twice the currently valid MAK value of 5,7 mg/m3. With this method simultaneously airborne 2‐phenoxyethanol in the gaseous state as well as particles are collected. Sampling is performed by drawing a defined volume of air through a quartz fibre filter located in the sampling head with an adsorption tube filled with Tenax TA connected downstream using a suitable pump. The flow rate is set to 0.066 L/min with a recommended air sample volume of approx. 4 litres. The collected 2‐phenoxyethanol alcohol is thermally desorbed and then analysed by means of gas chromatography using two detectors, a FID for quantification and a MSD to recognise potential interferences. The quantitative determination is based on a calibration function obtained by means of a multi‐point calibration. The limit of quantification is 0,095 mg/m3based on an air sample of approx. 4 litres.
Addendum zu Tetrachlorethen [BAT Value Documentation in German language, 2018]
Authors: Bolt H.M. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

In 2017, the German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated tetrachloroethylene [CAS No. 
127‐18‐4
] considering tetrachloroethylene in blood to characterize the internal exposure at the workplace. Available publications are described in detail.

The exposure equivalents for carcinogenic substances (EKA) of tetrachloroethylene uptake by inhalation and tetrachloroethylene in blood were confirmed and extended due to recent data.

The evaluation of the BAT value was based on the relationship between tetrachloroethylene uptake by inhalation at the MAK value and the corresponding concentration of tetrachloroethylene in blood. An eight‐hour exposure to the present MAK value of 10 ml tetrachloroethylene/m
3
correlates 16 hours after exposure with a mean tetrachloroethylene concentration in blood of approximately 200 µg/l. Therefore, a BAT value of 200 µg tetrachloroethylene/l blood was evaluated. Sampling time is 16 hours after exposure.
Addendum zu Ethylenglykoldinitrat [BAT Value Documentation in German language, 2018]
Authors: Klotz K. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the biological tolerance value (BAT value) for ethylene glycol dinitrate [CAS No. 
628‐96‐6
] in 2017.

Aim of this re‐evaluation was the lowering of the MAK value from 0.05 to 0.01 mL/m³ (for the sum of ethylene glycol dinitrate, nitroglycerin and propylene glycol dinitrate). The former BAT value of 0.3 µg ethylene glycol dinitrate/L blood was based on a correlation between external and internal exposure to the former MAK value of 0.05 ml/m³. The limit of detection of the applied analytical method was 0.2 µg ethylene glycol dinitrate/L blood. Correlating values of ethylene glycol dinitrate to the present MAK value would result in values below the limit of detection. Further studies and more sensitive analytical methods are missing. Therefore, the BAT value was withdrawn.
Addendum zu Aluminium [BAT Value Documentation in German language, 2018]
Authors: Klotz K. , Meyer‐Baron M. , van Thriel C. , Pallapies D. , Nasterlack M. , Letzel S. , Roßbach B. , Triebig G. , Weistenhöfer W. , Drexler H. , Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the biological tolerance value (BAT value) for aluminium [CAS No. 
7429‐90‐5
] in 2017. Available publications are described in detail.

The BAT value of 60 µg aluminium/g creatinine evaluated in 2009 was based on the linear correlation between external and internal exposure. Aim of this re‐evaluation was the derivation of a health‐based BAT value considering the most sensitive critical effect of aluminium, the neurotoxicity. For this purpose, the available studies of aluminium‐exposed workers were taken into account, when the internal aluminium exposure as well as the occurrence of subclinical neurotoxic effects were determined. The effects had been measured with standardised neuropsychological test procedures. From these studies, a no observed adverse effect level (NOAEL) of 50 µg/g creatinine for the occurrence of subtle neurotoxic effects of humans was estimated. Therefore, a BAT value of 50 µg aluminium/g creatinine was evaluated. Sampling time for long‐term exposures is at the end of the shift after several shifts.
Arsen und Arsenverbindungen – Bestimmung von Arsenspezies (As(III), As(V), Monomethylarsonsäure, Dimethylarsinsäure und Arsenobetain) in Urin mittels HPLC‐ICP‐MS [Biomonitoring Methods in German language, 2018]
Authors: Schramel P. , Michalke B. , Emons H. , Göen T. , Hartwig A. ,   MAK Commission
Published: October 2018

The working group “Analyses in Biological Materials” of the Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area verified the presented biomonitoring method.

The analytical method described hereinafter permits the simple and specific determination of the arsenic species arsenic (III) (As3+), arsenic (V) (As5+), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and arsenobetaine in urine. The limits of quantitation allow the quantification of the above‐mentioned arsenic species in both occupational and environmental medicine.

To this end, the arsenic species are separated by anion‐exchange high‐performance liquid chromatography (anion‐exchange HPLC) and detected by inductively coupled plasma mass spectrometry (ICP‐MS). Sample preparation is done by diluting the urine with water. Calibration is performed using either single or mixed standards of the different arsenic species or using the standard addition method.

The method was extensively validated and the reliability data were confirmed by an independent laboratory, which has established and cross‐checked the whole procedure.
Methyl vinyl ether [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of methyl vinyl ether [
107‐25‐5
].

There are no new data. Methyl vinyl ether was assessed in two 28 day inhalation studies, the first with 5 male and 5 female rats each and concentrations of 0, 500, 3500, 25 000 ml/m
3
and a second with 10 male rats each and concentrations of 0, 150, 500, 1500 ml/m
3
. In the first study 3500 ml/m
3
was the systemic NOAEC for females and local NOAEC for males and females. In male rats, changes in haematological and clinico‐chemical parameters were observed in all exposure groups independent of the concentration. These effects could not be reproduced in the second study. At 3500 ml/m
3
the body weight gains of male rats were reduced. This reduction was not seen in the second study with a higher number of animals. Therefore the commission now evaluates the effects at 3500 ml/m
3
as incidental, maybe due to the lower number of animals, and defined 3500 ml/m
3
as NOAEC. As the margin of the MAK value of 200 ml/m
3
to slight effects at 25 000 ml/m
3
is large enough it also accounts for the increased respiratory volume at the workplace (the blood:air partition coefficient of methyl vinyl ether is > 5; see List of MAK‐ and BAT Values, Sections I b and I c). Therefore the MAK value of 200 ml/m
3
is confirmed.

Since a systemic effect is critical, Peak Limitation Category II is retained. No data concerning half‐life are available; therefore the default excursion factor of 2 is confirmed.

For rats, the NOAEC for developmental toxicity after inhalation is 5000 ml methyl vinyl ether/m
3
, at 10 000 ml/m
3
variations and retarded ossification were observed. Even considering the increased respiratory volume at the workplace the difference of the NOAEC for developmental toxicity to the MAK value is sufficient so that methyl vinyl ether remains assigned to Pregnancy Risk Group C.
1‐Ethoxy‐2‐propanol [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value), the Pregnancy Risk Group and absorption through the skin of 1‐ethoxy‐2‐propanol [
1569‐02‐4
].

1‐Ethoxy‐2‐propanol is irritating to the eyes of rabbits and can damage the cornea. The critical systemic effects are pale foci in the lung and increased urine volume in rats after 13 weeks inhalation. The NAEC of these effects is estimated at 250 ml/m
3
, which results in a decreased MAK value of 20 ml/m
3
(88 mg/m
3
). This value also protects against possible irritation, as local effects are not observed up to 2000 ml/m
3
in the 13‐week rat inhalation study.

Since the critical effect of 1‐ethoxy‐2‐propanol is systemic, Peak Limitation Category II is retained. There is no specific toxicokinetic data available, so that the default excursion factor of 2 is confirmed.

New data on reproduction toxicity with 1‐ethoxy‐2‐propanol are not available. 1‐Ethoxy‐2‐propanol remains assigned to Pregnancy Risk Group C.

Skin contact is expected to contribute significantly to systemic toxicity and 1‐ethoxy‐2‐propanol remains designated with “H”.
Nitroglycerin [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value) and the Pregnancy Risk Group of nitroglycerin [55‐63‐0].

The critical effect in volunteers after a 25‐minute exposure to 0.05 ml/m3of a mixture of ethylene glycol dinitrate and nitroglycerin was vasodilation, as indicated by the development of headaches or decreases in blood pressure. In workers, headaches were reported at nitroglycerin concentrations of 0.03 to 0.11 ml/m3with a NOAEC below 0.01 ml/m3nitroglycerin. Based on this data, the MAK value for nitroglycerin was established at 0.01 ml/m3. As the MAK value is derived from experiences in workers, the increased respiratory volume at the work place is considered.

The MAK value also applies to the sum of the concentrations of the three nitrate esters nitroglycerin, ethylene glycol dinitrate and propylene glycol dinitrate in the air. As systemic effects are critical, the assignment to Peak Limitation Category II and the excursion factor of 1, due to the short half‐life, are retained.

In rats, the NOAEL for developmental toxicity after oral application is 86 mg/kg body weight and day. After toxicokinetic scaling this dose corresponds to a concentration of 16 ml/m3at the work place. The difference of this concentration to the MAK value is sufficient, therefore, nitroglycerin remains assigned to Pregnancy Risk Group C.

Skin contact may contribute significantly to systemic toxicity and nitroglycerin continues to be designated with an “H”. Sensitization is not expected from the limited data.
Ethylene glycol dinitrate [MAK Value Documentation, 2017]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) of ethylene glycol dinitrate [628‐96‐6] of 0.05 ml/m3, considering all toxicity endpoints. A detailed description of the underlying studies is given.

The critical effect in volunteers after a 25‐minute exposure to 0.05 ml/m3of a mixture of ethylene glycol dinitrate and nitroglycerin was vasodilation, as indicated by the development of headaches or decreases in blood pressure. The effects were very slight. In occupational situations it is very difficult to assess the levels of exposure to ethylene glycol dinitrate that induce symptoms and effects, not only because exposure is usually to mixtures of organic nitrate esters, but also because of both respiratory tract and skin absorption of ethylene glycol dinitrate vapours. In workers, headaches were reported at nitroglycerin concentrations of 0.03 to 0.11 ml/m3with a NOAEC below 0.01 ml/m3nitroglycerin. Based on this data, the MAK value for nitroglycerin was established at 0.01 ml/m3. Because of the same mode of action and the similar LOAEC of the two substances, the MAK value for ethylene glycol dinitrate has been lowered to 0.01 ml/m3. The MAK value also applies to the sum of the concentrations of the two substances in the air. As systemic effects are critical, the assignment to Peak Limitation Category I and the excursion factor of 1, due to the short half‐life, are retained. Although there are no studies on developmental toxicity, ethylene glycol dinitrate is assigned to Pregnancy Risk Group C in analogy to nitroglycerin. No data are available for genotoxicity or carcinogenicity. Skin contact may contribute significantly to systemic toxicity and ethylene glycol dinitrate continues to be designated with an “H”. Sensitization is not expected from the limited data.
Acetonitrile [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of acetonitrile [
75‐05‐8
].

Acetonitrile causes an increased incidence of liver adenomas and carcinomas in rats at 400 ml/m
3
with a statistically significant trend. The number of basophilic foci in the liver is positively correlated with the exposure concentration. At 100 ml/m
3
the elevation is not statistically significant, however, these foci are regarded as preneoplastic lesions. From this concentration the former MAK value of 20 ml/m
3
was derived. It is now lowered to 10 ml/m
3
taking into account the increased respiratory volume at the workplace because the blood:air partition coefficient of acetonitrile is > 5 (see List of MAK and BAT Values, Sections I b and I c). Since a systemic effect is critical, Peak Limitation Category II is retained. As the effects are probably due to the metabolites, the default excursion factor of 2 is confirmed despite the long half‐life of acetonitrile.

For rabbits, the NOAEL for developmental toxicity after gavage is 15 mg/kg body weight and day. After toxicokinetic scaling this dose corresponds to a concentration of 34 ml/m
3
at the workplace. Rabbits are more sensitive to acetonitrile than rats and humans and the developmental toxicity of acetonitrile is higher after gavage than after inhalation exposure as shown with rats. Therefore, the rabbit gavage data are not used to assign a Pregnancy Risk Group. The NOAEC for developmental toxicity in rats is 1600 ml/m
3
and after considering the increased respiratory volume at the workplace the difference to the MAK value is sufficient. Therefore, damage to the embryo or foetus is unlikely when the MAK value is observed and acetonitrile remains assigned to Pregnancy Risk Group C.
Trimethylamine [MAK Value Documentation, 2016]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the work place (MAK value) of trimethylamine [
75‐50‐3
] of 2 ml/m
3
, considering the endpoints local and systemic toxicity as well as developmental toxicity. Available publications are described in detail. Daily exposure of rats to trimethylamine for 14 days resulted in inflammation of the respiratory epithelium at 74 ml/m
3
, the lowest concentration tested. Since 2014, the Commission uses an empirical approach to set MAK values for substances with critical effects on the upper respiratory tract or the eyes. According to this approach, the MAK value would have to be lowered to 1 ml/m
3
. However, several data show, that the previous MAK value can be retained. Workers reported no irritation at 5 ml trimethylamine/m
3
. In addition cyclohexylamine and dimethylamine with a MAK value of 2 ml/m
3
are used as a read‐across due to similar alkalinity and RD50 values, and in a recent volunteer study a NOAEC of 2 ml cyclohexylamine/m
3
is found. The MAK value will also protect from possible blue hazy vision which is caused by other tertiary amines since trimethylamine is assumed to be less effective than N,N‐dimethylethylamine with a MAK value of 2 ml/m
3
. The assignment is to Peak Limitation Category I, because local effects are critical, and the excursion factor of 2 is confirmed. Developmental toxicity studies with trimethylamine show that damage to the embryo or foetus is unlikely if the MAK value is observed, and the assignment to Pregnancy Risk Group C is retained.
Citric acid and its alkali metal salts [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated citric acid [77‐92‐9] and its alkali metal salts, considering all toxicological endpoints.

The critical effect of citric acid is the irritation of the respiratory tract with an acute LOAEC of 225 mg/m3in humans and 81 mg/m3in guinea pigs. At this concentration coughing is induced due to the lowering of the pH value. The NOAEC in guinea pigs is 31 mg/m3, the corresponding NOAEC in humans is not known. Studies with repeated inhalation are not available. Therefore, the maximum concentration at the workplace (MAK value) has been set by analogy with the MAK value for phosphoric acid of 2 mg/m3as inhalable fraction. Since a local effect is critical, Peak Limitation Category I is designated. The excursion factor of 2 is set by analogy with phosphoric acid.

The alkali metal salts of citric acid are not irritating, which precludes setting the same MAK value for the salts as for citric acid. However, a higher MAK value cannot be established because the systemic NOAEL is unclear. Therefore, no MAK value can be set for the alkali metal salts of citric acid.

The oral NOAEL for developmental toxicity in rats, mice, rabbits and hamsters is higher than 200 mg citric acid/kg body weight, which after toxicokinetic scaling corresponds to more than 200 mg/m3at the workplace. Therefore, damage to the embryo or foetus is unlikely when the MAK value is observed and citric acid is assigned to Pregnancy Risk Group C.

Citric acid does not possess a relevant genotoxic potential in vivo. The same is assumed for its alkali metal salts. There are no valid carcinogenicity studies with citric acid. A tumour promoting effect of sodium citrate but not citric acid in the rat urinary bladder is due to excessively high sodium concentration in the urine and is therefore not relevant for humans at the workplace.

According to skin absorption models, percutaneous absorption of citric acid does not contribute significantly to systemic toxicity. The same is assumed for its alkali metal salts. Citric acid and its alkali metal salts are not sensitizing to skin or airways.
N‐Vinyl‐2‐pyrrolidone [MAK Value Documentation, 2018]
Authors: Hartwig A. ,   MAK Commission
Published: October 2018

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated the maximum concentration at the workplace (MAK value) and the Pregnancy Risk Group of N‐vinyl‐2‐pyrrolidone [
88‐12‐0
].

N‐Vinyl‐2‐pyrrolidone is a non‐genotoxic carcinogen in liver, nose and larynx of rats. In 28‐day inhalation studies it was shown that cell proliferation in liver and hyperplasia in the nasal epithelia of rats is increased at 0.5 ml/m
3
with a NOAEC of 0.2 ml/m
3
. The former MAK value of 0.02 ml/m
3
was derived from this concentration, the MAK value is now lowered to 0.01 ml/m
3
. This takes into account the increased respiratory volume at the workplace, because the blood:air partition coefficient of N‐vinyl‐2‐pyrrolidone is > 5 (see List of MAK and BAT Values, Sections I b and I c). Since a systemic effect is critical, Peak Limitation Category II is retained. As the critical metabolite is not known, the default excursion factor of 2 for systemically acting compounds is confirmed.

For rats, the NOAEC for developmental toxicity after inhalation is 5 ml N‐vinyl‐2‐pyrrolidone/m
3
, where reduced maternal body weight gain occurred. At 20 ml/m
3
reduced foetal bodyweight and an increase of variations were observed. Taking into account the increased respiratory volume at the work place the NOAEC for developmental toxicity is 250 times higher than the MAK‐value. Therefore, N‐vinyl‐2‐pyrrolidone remains assigned to Pregnancy Risk Group C.
Decision Analysis
Authors: Chan Yupo
Published: October 2018

This entry reviews how decision analysis contributes to the field of methods, models, and geographic information science. It focuses in particular on multicriteria decision‐making and offers a case study of airport location to illustrate how this approach captures the complex negotiation between airport authorities and the public in siting a new airport. Importantly, decision analysis can offer implicit representation of a multi‐attribute utility function without an explicit mathematical expression. Instead, the value of the airport is captured in a site‐specific setting, where the interests of the stakeholders are revealed through a town hall meeting. The process converges toward an agreed‐upon airport site. Going beyond the immediate case study, a broader look at the insightful role of decision analysis in viewing classic facility location problems is discussed, including medians and centers. The entry ends with a projection of where the art and science of decision analysis are heading in the future in the context of geographic information sciences.
Urban Elites
Authors: Gyuris Ferenc
Published: October 2018

Urban elites consist of the actors in the city who have a decisive influence on urban policies and programs. Urban elites are fragmented, but are kept together by a shared interest in advancing a particular political agenda. This desire is served by a multitude of institutional means aimed at keeping other social strata under control and indoctrinating them with views legitimizing prevailing conditions. Urban elites are highly genderized, racialized, and segregated in urban space. Since they are embedded in multiscalar power hierarchies, urban elites can be conflicted, or even justified, by actors at higher or lower scales while they themselves are increasingly becoming part of a transnational elite. The existence of urban elites is unavoidable and not necessarily undesirable, but the way they sustain themselves and promote their own aspirations may be at odds with the interests of other social groups and is often the focus of ongoing normative debates.
Interoperability of Representations
Authors: Brodaric Boyan
Published: October 2018

The rapid growth of distributed geographical data and software has fueled development of interoperability approaches that enable such resources to function together for specific purposes. The problem at the heart of these approaches involves overcoming heterogeneity in the digital representation of geographical entities and related computing processes. Solutions uniformly include conversion to a preferred representation through transformation at various levels, such as systems, syntax, structure, semantics, and pragmatics. Major milestones include spatial database interoperability, Spatial Data Infrastructures, and Linked Data, which are characterized by the adoption of unique strategies at each interoperability level and by distinct architectural styles.
An algorithm for automated modulation transfer function measurement using an edge of a PMMA phantom: Impact of field of view on spatial resolution of CT images
Authors: Anam Choirul , Fujibuchi Toshioh , Budi Wahyu Setia , Haryanto Freddy , Dougherty Geoff
Published: October 2018

Purpose

The purpose of this study was to introduce a new algorithm for automated measurement of the modulation transfer function (MTF) using an edge of a readily available phantom and to evaluate the effect of reconstruction filter and field of view (FOV) on the spatial resolution in the CT images.

Methods

Our automated MTF measurement consisted of several steps. The center of the image was established and an appropriate region of interest (ROI) designated. The edge spread function (ESF) was determined, and a suitably interpolated ESF curve was differentiated to obtain the line spread function (LSF). The LSF was Fourier transformed to obtain the MTF. All these steps were accomplished automatically without user intervention. The results of the automated MTF from the edge phantom were validated by comparing them with a point image, and the results of the automated calculation were validated by the standard fitting method. The automated MTF calculation was then applied to the images of two polymethyl methacrylate (PMMA) phantoms and a wire phantom which had been scanned by a Toshiba Alexion 4‐slice CT scanner and reconstructed with various filter types and FOVs.

Results

The difference in the 50% MTF values obtained from the edge and point phantoms were within ±4%. The values from the automated and fitted methods agreed to within ±2%, indicating that the automated MTF calculation was accurate. The automated MTF calculation was able to differentiate MTF curves for various filters. The spatial resolution values were 0.37 ± 0.00, 0.71 ± 0.01, and 0.78 ± 0.01 cycles/mm for FC13, FC30 and FC52 filters, respectively. The spatial resolution of the images decrease linearly (R2 > 0.98) with increasing FOVs.

Conclusion

An automated MTF method was successfully developed using an edge phantom, the PMMA phantom. The method is easy to implement in a clinical environment and is not influenced by user experience.
California Medicaid waiver pushes more providers to use buprenorphine
Authors: Knopf Alison
Published: October 2018

California has embarked on an ambitious project to get opioid treatment programs (called narcotic treatment programs, or NTPs, in the state) to expand the medications they use, from just methadone to buprenorphine, naloxone (the opioid overdose reversal drug) and disulfiram (a medication that causes severe unpleasant reactions if someone on it drinks alcohol). Last week, ADAW talked to officials at the county membership organization to find out how this is going.
Self‐Assembled Aptamer Nanoconstruct: A Highly Effective Molecule‐Capturing Platform Having Therapeutic Applications
Authors: Lee Jihyun , Lee Junseok , Ree Brian J. , Lee Yeong Mi , Park Hyeongmok , Lee Tae Geol , Kim Jeong Hun , Kim Won Jong
Published: October 2018

Although the aptamer is a promising tool for binding and controlling the activity of a specific target molecule, its relatively low stability and capturing efficiency are major obstacles for its direct use in therapeutic applications. Herein, a 3D molecular capture system named the “constructed aptamer (CA)” is reported, which is formulated by the self‐assembly of the human vascular endothelial growth factor (hVEGF) aptamer block and Y‐shaped DNA blocks. The serum stability and target capturing efficiency exhibited by the CA are greater than that observed with the oligomeric aptamer and randomly amplified aptamer. In addition, successful intracellular uptake is observed by confocal laser scanning microscopy using fluorescence labeled CA. Finally, an enhanced antitumor effect is demonstrated in vivo, owing to the efficient inhibition of angiogenesis. Overall, the designed CA has great potential as a therapeutic platform for capturing a specific disease‐related molecule such as VEGF.
Re‐emerging role of macroscopic appearance in treatment strategy for gastric cancer
Authors: Hosoda Kei , Watanabe Masahiko , Yamashita Keishi
Published: October 2018

Pathological outcomes are definitely the most important prognostic factors in gastric cancer, but they can be obtained only after surgical resection. Use of preoperative adjuvant chemotherapy is becoming widespread for aggressive human cancer, so clinical factors such as macroscopic features are important as they are highly predictive for patient prognosis. In gastric cancer, the macroscopic type represents a distinct prognosis; Type 0 represents early gastric cancer with excellent prognosis, but, among advanced tumors, giant Type III and Type IV tumors have a dismal prognosis. Japan Clinical Oncology Group (JCOG) Stomach Cancer Study Group adopted macroscopic features as high‐risk entities in clinical trials. It makes sense for risk classification to use macroscopic phenotypes because The Cancer Genome Atlas (TCGA) Network has lately subcategorized different histologies associated with specific macroscopic types by the molecular features of the whole genome. Dismal prognosis of Type IV gastric cancer is notorious, but similar prognosis was seen in giant Type III gastric cancer defined as 8 cm or beyond, both of which are unique for their propensity of peritoneal dissemination. In this review, clinical relevance including prognosis of such macroscopic high‐risk features will be separately debated in the context of precision medicine and updated prognostic outcomes will be presented under the present standard therapy of curative surgery followed by postoperative S‐1 chemotherapy. Moreover, promising emerging novel therapeutic strategies including trimodal potent regimens or intraperitoneal chemotherapy will be described for such aggressive gastric cancer.
Formation of Hypoxanthine Tetrad by Reaction with Sodium Chloride: From Planar to Stereo
Authors: Chen Chong , Ding Pengcheng , Mura Manuela , Chen Yanghan , Sun Ye , Kantorovich Lev N. , Gersen Henkjan , Besenbacher Flemming , Yu Miao
Published: October 2018

By reacting with NaCl on Au(111), the formation of hypoxanthine (HX) tetrads is demonstrated at the atomic scale in real space. These results directly demonstrate that alternative purine tetrads can be formed in both planar and non‐planar configuration, and that ionic bonding plays a crucial role for the formation and planar‐to‐stereo transformation of the tetrads, providing deeper insight for constructing artificial DNA/RNA quadruplexes. Moreover, both the tilted HXs and Na show strong charge transfer with the substrate in the non‐planar phase. The insights gained by this work also open up new routes to tune the electrostatic nature of metal–organic interfaces and design stereo‐nanostructures on surfaces.
Chemo‐Enzymatic Synthesis of Pyrazines and Pyrroles
Authors: Xu Jin , Green Anthony P. , Turner Nicholas J.
Published: October 2018

Herein we report the biocatalytic synthesis of substituted pyrazines and pyrroles using a transaminase (ATA) to mediate the key amination step of the ketone precursors. Treatment of α‐diketones with ATA‐113 in the presence of a suitable amine donor yielded the corresponding α‐amino ketones which underwent oxidative dimerization to the pyrazines. Selective amination of α‐diketones in the presence of β‐keto esters afforded substituted pyrroles in a biocatalytic equivalent of the classical Knorr pyrrole synthesis. Finally we have shown that pyrroles can be prepared by internal amine transfer catalyzed by a transaminase in which no external amine donor is required.
Flexible Films of Covalent Organic Frameworks with Ultralow Dielectric Constants under High Humidity
Authors: Shao Pengpeng , Li Jie , Chen Fan , Ma Li , Li Qingbin , Zhang Mengxi , Zhou Junwen , Yin Anxiang , Feng Xiao , Wang Bo
Published: October 2018

Covalent organic framework (COF) films combine the processability of polymers with the porosity and atomic precision of crystalline porous materials, properties that are long‐sought‐after in electronics yet hard to realize. Herein, we prepared four flexible COF films with different alkoxy side chains via interfacial polymerization. The COF films exhibit an ultralow dielectric constant (κ=1.19±0.04 at 105 Hz), small dielectric loss (<0.02, 103–106 Hz), high breakdown voltage (>63 kV cm−1) and low leakage current (10−10 A cm−2 at 1 kV cm−1). They have considerable mechanical strength, and ability to withstand high humidity (RH 70 % for 10 days) and repeated bending (1000 times) without losing their dielectric properties. Extension of the alkoxy chains reduces the film's κ and enhances its moisture resistance, while incorporation of guest molecules further increase the κ value up to 43 times.
Black Box Parenting Program for Substance‐Abusing Fathers: A Feasibility Study
Authors: Torres Marianne , Deane Frank P. , Sng Rebecca , Quinlan Elly
Published: October 2018

Substance‐abusing fathers have reported parenting difficulties and there is a need for interventions that address these concerns and support these men. The present study conducted a feasibility trial of the Black Box Parenting Program for fathers in residential substance abuse treatment settings. The study had a mixed methods design that assessed for demand, implementation, preliminary efficacy, and acceptability. Measures included pre‐ and post‐questionnaires on parenting self‐efficacy and satisfaction, perceived closeness in the parent–child relationship, feelings of guilt and engagement, and satisfaction with treatment. In addition, semi‐structured interviews were conducted with participants post‐treatment. Across four groups, the 19 fathers successfully completed the program. Following the intervention, there was a significant decrease in feelings of guilt and a strong motivation to continue to seek help with parenting. Parental self‐efficacy and perceived closeness in the parent–child relationship did not significantly improve from pre to post‐treatment. Qualitative data indicate that fathers were very satisfied with the program. Satisfaction with treatment was strongly related to parental self‐efficacy. Systemic barriers prevented delivery of the program at some treatment sites and parts of the program could not be implemented at multiple sites. Overall, the program shows promise in being able to reduce the barriers to help‐seeking such as guilt and poor retention. However, it requires the right service structure to achieve successful implementation.
Synthesis and characterization of superparamagnetic nanohybrid Fe3O4/NH2‐Ag as an effective carrier for the delivery of acyclovir
Authors: Hoseininasr Atefe S. , Tayebee Reza
Published: October 2018

In this work, superparamagnetic nanohybrid material Fe3O4/NH2‐Ag is uncovered as an attractive magnetic carrier for the controlled delivery of acyclovir (ACV). This magnetic nanoparticle was synthesized using the hydrothermal method. Then, the surface hydroxyl groups were extended by treating with tetraethyl orthosilicate (TEOS) and (3‐aminopropyl) trimethoxysilane (APTMS). Finally, Ag nanoparticles were created on the surface of Fe3O4@SiO2‐NH2 nanospheres via reduction of Ag+ ions. Decorated hybrid magnetite nanoparticles were then loaded with ACV as an active antiviral drug model. For this purpose, the amount of loading/release of the drug was investigated at different pH values. Structural characteristics of the functionalized nanomagnetic materials were investigated by Fourier transform‐infrared spectroscopy, transmission electron microscopy, X‐ray diffraction, thermogravimetric analysis and vibrating‐sample magnetometry. The findings indicated that Fe3O4/NH2‐Ag is highly efficient in loading and release of the selected model drug at pH 7.4.
Coordination behaviour and biological activity studies involving theoretical docking of bis‐Schiff base ligand and some of its transition metal complexes
Authors: Zayed Ehab M. , Zayed Mohamed A. , Hindy Ahmed M.M. , Mohamed Gehad G.
Published: October 2018

The Schiff base ligand 1,2‐bis(2‐vinylphenoxy)ethane‐4,6‐diaminopyrimidine‐2‐thiol derived from the condensation of 4,6‐diaminopyrimidine‐2‐thiol with bisaldehyde was synthesized and characterized. Coordination compounds of this Schiff base with transition metal cations Cd(II), Zn(II), Ni(II), Co(II), Mn(II), Cu(II) and Fe(III) were synthesized and characterized. Microanalytical data, magnetic moments, mass, 1H NMR and infrared spectra, molar conductance measurements and thermal analyses were used to confirm the structures of the obtained Schiff base ligand and its chelates. According to the data obtained, the 1:1 general stoichiometric formulae of chelates are given by [M(HL)(H2O)2]Cl2 (M = Cd(II), Zn(II), Ni(II), Co(II), Mn(II), Cu(II)) and [Fe(HL)(H2O)2]Cl3. The diffuse reflectance spectra and magnetic moment measurements suggest an octahedral geometry for the complexes. The bis‐Schiff base ligand and metal ions are coordinated in a tetradentate manner via OO and NN donor sites as confirmed by infrared spectra. These complexes were then subjected to antibacterial studies using Gram‐positive (Streptococcus pyogenes and Bacillus subtilis) and Gram‐negative (Proteus vulgaris and Escherichia coli) organisms. The ligand and metal complexes exhibited pronounced antimicrobial activity against both types of bacteria. A docking study was conducted to evaluate the nature of the binding of the ligand and the most biologically active complexes to protein active sites of these bacteria.
Catalytic asymmetric 1,2‐Addition/Lactonization tandem reactions for the syntheses of chiral 3‐Substituted phthalides using organozinc reagents
Authors: Huang Huayin , Wang Yabai , Zong Hua , Song Ling
Published: October 2018

Using chiral phosphoramide ligand 2d‐Zn (II) complex derived from (1R,2R)‐1,2‐diphenylethylenediamine as the catalyst, we have developed efficient catalytic asymmetric 1,2‐addition/lactonization tandem reactions of diverse organozinc reagents with varied methyl 2‐formylbenzoates for the construction of optically enriched 3‐aryl or alkyl substituted phthalides, which are significant building blocks of many important chiral pharmaceuticals and natural products. The corresponding products could be afforded with good to excellent yields (up to 95%) and moderate to good enantioselectivities (up to 89%).