bluuebunny/crossref_metadata_2025 huggingface dataset:
Postoperative Hemorrhage From Racemose Hemangioma of the Bronchial Artery After Esophageal Cancer Surgery
Authors: Takebayashi Katsushi , Tsubosa Yasuhiro , Matsuda Satoru , Kawamorita Keisuke , Niihara Masahiro , Aramaki Takeshi , Sato Hiroshi
Published: January 2017

Racemose hemangioma of the bronchial artery is a rare disease. The diagnosis of racemose hemangioma is difficult when affected patients are asymptomatic and causes unexplained hemoptysis. Selective bronchial artery embolization has become the first-line treatment for this rare disease. However, feasibility and safety of bronchial artery embolization was not reported in the case with permanent tracheostomy. A 44-year-old woman underwent endoscopic screening during which a circular tumor was detected in the cervical esophagus, which was confirmed as squamous cell carcinoma on biopsy. She underwent cervical esophagectomy with pharyngolaryngectomy through a cervical incision. Reconstruction was performed by free jejunal transfer and permanent tracheostomy. Six weeks after surgery, hemoptysis from permanent tracheostomy was observed. Computed tomography (CT) scan revealed no bleeding around the tracheostomy, and bronchoscopy could not identify the origin of the bleeding due to a large amount of blood clots obscuring the visual field. Bronchial arteriography showed a bent, meandering and dilated bronchial artery, extending to the right bronchus with vascular hyperplasia. We diagnosed primary racemose hemangioma of the bronchial artery, which was successfully treated by transcatheter arterial embolization of the bronchial artery. After embolization, bronchoscopy revealed no bleeding. Findings from this case suggest that bronchial angiography is essential for diagnosis of this disease, and selective bronchial artery embolization appears to be effective in treating this disease in patients with permanent tracheostomy. Accumulation of similar cases will help to elucidate the optimal diagnosis and treatment strategy for this condition.
Anatomy of a late spring snowfall on sea ice
Authors: Perovich Donald , Polashenski Christopher , Arntsen Alexandra , Stwertka Carolyn
Published: January 2017

Spring melt initiation is a critical process for Arctic sea ice. Melting conditions decrease surface albedo at a time of high insolation, triggering powerful albedo feedback. Weather events during melt initiation, such as new snowfalls, can stop or reverse the albedo decline, however. Here we present field observations of such a snow event and demonstrate its enduring impact through summer. Snow fell 3–6 June 2014 in the Chukchi Sea, halting melt onset. The snow not only raised albedo but also provided a significant negative latent heat flux, averaging ‐51 W m−2 from 3 to 6 June. The snowfall delayed sustained melt by 11 days, creating cascading impacts on surface energy balance that totaled some 135 MJ/m2 by mid‐August. The findings highlight the sensitivity of sea ice conditions on seasonal time scales to melt initiation processes.
Improving synoptic and intraseasonal variability in CFSv2 via stochastic representation of organized convection
Authors: Goswami B. B. , Khouider B. , Phani R. , Mukhopadhyay P. , Majda A.
Published: January 2017

To better represent organized convection in the Climate Forecast System version 2 (CFSv2), a stochastic multicloud model (SMCM) parameterization is adopted and a 15 year climate run is made. The last 10 years of simulations are analyzed here. While retaining an equally good mean state (if not better) as the parent model, the CFS‐SMCM simulation shows significant improvement in the synoptic and intraseasonal variability. The CFS‐SMCM provides a better account of convectively coupled equatorial waves and the Madden‐Julian oscillation. The CFS‐SMCM exhibits improvements in northward and eastward propagation of intraseasonal oscillation of convection including the MJO propagation beyond the maritime continent barrier, which is the Achilles Heel for coarse‐resolution global climate models (GCMs). The distribution of precipitation events is better simulated in CFSsmcm and spreads naturally toward high‐precipitation events. Deterministic GCMs tend to simulate a narrow distribution with too much drizzling precipitation and too little high‐precipitation events.
Concentric traveling ionosphere disturbances triggered by Super Typhoon Meranti (2016)
Authors: Chou Min Yang , Lin Charles C. H. , Yue Jia , Tsai Ho Fang , Sun Yang Yi , Liu Jann Yenq , Chen Chia Hung
Published: January 2017

Concentric traveling ionosphere disturbances (CTIDs) in total electron content triggered by Super Typhoon Meranti on 13 September 2016 are detected by using the ground‐based Global Navigation Satellite Systems network in Taiwan. The CTIDs emanated outward before the typhoon landfall and lasted for more than 10 h. The characteristics of CTIDs agree with the gravity wave theory and exhibit spatial and temporal scales in wave periods of ~8–30 min, horizontal wavelengths of ~160–200 km, and horizontal phase velocities of ~106–220 m/s. We also observe the CTIDs showing the stationary wave character. Broad spectra of CTIDs are excited after the rainbands of typhoon impinged on Central Mountain Range of Taiwan. The ray‐tracing technique confirms that the CTIDs were excited by convective clouds, spiral rainbands, and the eyewall of Typhoon Meranti. This study provides new evidence of typhoon‐induced concentric gravity waves in the ionosphere.
Effect of orbital angular momentum on electron acoustic waves in double‐Kappa plasma
Authors: Rehman Aman‐ur , Shan S. Ali , Hamza M. Yousaf , Lee J. K.
Published: January 2017

Kinetic theory of electron acoustic waves (EAWs) in the presence of wave angular momentum has been derived to study the effect of wave angular momentum on the propagation of EAWs in a non‐Maxwellian plasma. Both types of electrons (hot and cool) are modeled as Kappa‐distributed velocity distribution functions. The theory is also applied to Saturn's magnetosphere where these kinds of distribution functions are commonly found. It is seen that the presence of wave angular momentum in the model has a significant effect on the existence of the regions where EAWs are weakly damped. The effect of wave angular momentum on EAWs is studied by defining a parameter η = k/(lqθ), which is the ratio of the planar wave number to the azimuthal wave number. The wave is purely planar if
. The weakly damped region of EAWs depends strongly on this parameter in addition to other parameters such as hot electron spectral index κh, cool electron spectral index κc, the fraction of hot electrons, and hot to cool electrons temperature ratio. The results also show the effect of η on the propagation of EAWs in various regions of Saturn's magnetosphere.
Ion density and temperature profiles along (XGSM) and across (ZGSM) the magnetotail as observed by THEMIS, Geotail, and ARTEMIS
Authors: Artemyev A. V. , Angelopoulos V. , Hietala H. , Runov A. , Shinohara I.
Published: January 2017

Characteristics of the two‐dimensional configuration of the magnetotail current sheet are important for modeling magnetotail motion/evolution and charged particle energization. Because of the magnetotail current sheet's dynamical nature, however, simultaneous plasma and magnetic field measurements at different radial distances are required to reveal this configuration. Simultaneous observations of the magnetotail current sheet from Time History of Events and Macroscale Interactions during Substorms (THEMIS) D (around 10RE downtail), Geotail (around 30RE downtail), and Acceleration, Reconnection, Turbulence and Electrodynamics of the Moons Interaction with the Sun (ARTEMIS) P1 (around 55RE downtail) are used to study distributions of plasma (ion) density and temperature along (Earth‐Sun direction) and across (north‐south direction) the magnetotail. Fourteen events (each including several current sheet crossings at different downtail distances) are studied. We demonstrate that the plasma temperature along and across the magnetotail varies more significantly than plasma density does. The temperature decrease from equatorial plane to current sheet boundaries is a major contributor to the cross‐tail pressure balance. The Alfven velocity VA,B calculated at the current sheet boundaries increases significantly toward the Earth from 700 km/s at lunar orbit ∼55RE to 2200 km/s around ∼10RE downtail. The corresponding energy
(mp is the proton mass) is 4 times larger than the plasma temperature T0 in the magnetotail's equatorial plane, whereas the ratio EA/T0 is constant along the magnetotail. The plasma temperature T0 measured around lunar orbit in the magnetotail agrees well with the simultaneously measured energy of solar wind protons
(VSW is the solar wind speed).
Post‐emplacement cooling and contraction of lava flows: InSAR observations and a thermal model for lava fields at Hekla volcano, Iceland
Authors: Wittmann Werner , Sigmundsson Freysteinn , Dumont Stéphanie , Lavallée Yan
Published: January 2017

Lava flows contract as they cool, causing progressive subsidence of the flow surface. Here we study this process by measuring and modeling the deformation of emplaced lava flows and the surrounding substrate. The temporal trend of vertical lava movements was investigated using interferometric analysis of synthetic aperture radar (InSAR) images from the 1991 and 2000 Hekla eruptions, covering periods of 23 and 12 years, respectively. Data from six tracks from three satellites, including both ascending and descending passes, were used to create 99 interferograms, from which trends of accumulated subsidence and subsidence velocities were derived. Subsidence rates are similar for both lava flows and decay approximately exponentially from about 20 mm/yr 5 years after emplacement to about 2 mm/yr 15 years after emplacement. A one‐dimensional, semi‐analytical model was fitted to the observed subsidence rates, with subsidence due to phase change calculated analytically and subsidence due to thermal contraction calculated numerically using dilatometric constraints obtained experimentally. The initial thicknesses of the 1991 and 2000 lava fields, D1991 and D2000, scaled thermal expansivity, γα, and thermal diffusivity, κ, are the crucial parameters influencing lava subsidence and subsidence rate. Inversion for these parameters reveal linear correlations between them. Best fitting results of inversions for D1991 range from 10 m to 27 m, for D2000 from 10 m to 30 m, γα= 9–24 ×10−6 K−1, and κ= 1–7 ×10−7 m2 s−1.
Improving Global Forecast System of extreme precipitation events with regional statistical model: Application of quantile‐based probabilistic forecasts
Authors: Shastri Hiteshri , Ghosh Subimal , Karmakar Subhankar
Published: January 2017

Forecasting of extreme precipitation events at a regional scale is of high importance due to their severe impacts on society. The impacts are stronger in urban regions due to high flood potential as well high population density leading to high vulnerability. Although significant scientific improvements took place in the global models for weather forecasting, they are still not adequate at a regional scale (e.g., for an urban region) with high false alarms and low detection. There has been a need to improve the weather forecast skill at a local scale with probabilistic outcome. Here we develop a methodology with quantile regression, where the reliably simulated variables from Global Forecast System are used as predictors and different quantiles of rainfall are generated corresponding to that set of predictors. We apply this method to a flood‐prone coastal city of India, Mumbai, which has experienced severe floods in recent years. We find significant improvements in the forecast with high detection and skill scores. We apply the methodology to 10 ensemble members of Global Ensemble Forecast System and find a reduction in ensemble uncertainty of precipitation across realizations with respect to that of original precipitation forecasts. We validate our model for the monsoon season of 2006 and 2007, which are independent of the training/calibration data set used in the study. We find promising results and emphasize to implement such data‐driven methods for a better probabilistic forecast at an urban scale primarily for an early flood warning.
Breakup modes of the drops suspended in a vertical wind tunnel in presence of the horizontal electric field
Authors: Bhalwankar Rohini , Deshpande C. G. , Kamra A. K.
Published: January 2017

The influence of strong horizontal electric field (EH) on different stages of deformation and eventual breakup of the large water drops of 6.6, 7.0, and 7.25 mm diameter has been observed in a vertical wind tunnel using high‐speed photography. Dumbbell, filament, and bag modes of drop breakup are observed when EH = 0. However, drops elongate in horizontal direction, mostly develop sharp curvature at their ends, eject a fine jet spray of tiny droplets, and ultimately break up into several droplets in EH = 500 kV m−1. Extreme elongation up to 29 mm is observed for a 7.0 mm diameter drop. Results show that the breakup time, i.e., the time from the drop's extreme prolate shape to its breakup in its final oscillation, ranges from 13 to 41 ms when EH = 0 and 57–105 ms when EH = 500 kV m−1. So although the lifetime of the drop since its suspension to breakup is reduced, its elongation and breakup time increase in EH. It suggests that the effect of EH in final oscillation before breakup overcomes the effect of hydrodynamic and aerodynamic forces in elongating the drop. Also, no breakup of bag type is observed in EH = 500 kV m−1. Moreover, the fragments formed after the drop breakup and tiny droplets ejected by their fragments carry electrical charges of polarity determined by the induced charge on the parent drop in EH. The significance of the results is discussed in modifying the drop growth and the radar echo‐precipitation relationships in thunderclouds.
Calibration [Air Monitoring Methods, 2016]
Authors: Hebisch R. , Ball M. , Breuer D. , Heckmann P. , Krämer W. , Maschmeier C.‐P. , Nitz G. , Riepe W. , Schuh C. , Brock T.H. , Hartwig A. ,   MAK Commission
Published: January 2017

Workplace measurements are intended to give information about kind and extent of workers' exposure during their activities with hazardous substances. For this purpose calibration is necessary to establish the relationship between a known concentration and the corresponding measuring signal resulting in reliable measuring results at a high level of quality. Therefore, calibration strongly influences accuracy and precision of the whole measuring procedure. Calibration is required for different tasks. During development of a measurement procedure the calibration range has to be determined, for which there must be a linear relationship between the concentration of the analyte and the response of the analytical procedure. Important analytical parameters such as limit of detection (LOD) and limit of quantification (LOQ) may also be determined using calibration procedures. Normally, calibration is needed for the quantification of hazardous substances from workplace measurements. In this case the composition of calibration solutions should be as near as possible to that of the collected samples. The calibrated concentration range should yield unambiguous analytical results. Traceability of the complete calibration procedure from the measuring result back to the typically used (certified) reference material must be ensured. This chapter describes how to perform calibration for different purposes and the possible sources of errors which have to be considered. Requirements for reference materials are also specified.

Joint Publication of the Analytical Subcommittee of the Chemistry Board of Experts of the Expert Committee Raw Materials and Chemical Industry of the German Social Accident Insurance and the Working Group “Air Monitoring Methods” of the Permanent Senate Commission of the DFG for the Investigation of Health Hazards of Chemical Compounds in the Work Area.
2‐Ethylhexyl acetate [MAK Value Documentation, 2014]
Authors: Hartwig A. ,   MAK Commission
Published: January 2017

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated 2‐ethylhexyl acetate to derive a maximum concentration at the workplace (MAK value), considering all toxicological endpoints examined. Available publications and unpublished study reports are described in detail. 2‐Ethylhexyl acetate is rapidly hydrolysed to 2‐ethylhexanol and acetic acid. Local irritation is the critical effect of 2‐ethylhexanol and acetic acid, and the same is assumed for 2‐ethylhexyl acetate. Studies with repeated inhalation exposure or oral administration to 2‐ethylhexyl acetate are not available. By analogy with its metabolites 2‐ethylhexanol and acetic acid, a MAK value of 10 ml/m3has therefore been established for 2‐ethylhexyl acetate. 2‐Ethylhexyl acetate has been classified by analogy with 2‐ethylhexanol in Peak Limitation Category I with an excursion factor of 1. 2‐Ethylhexyl acetate is not expected to have genotoxic effects. The metabolite 2‐ethylhexanol caused liver tumours in a long‐term study with oral administration only at clearly toxic doses of 750 mg/kg body weight and day and only in female mice. If the MAK value, which protects against liver toxicity, is observed, liver tumours are not expected. Skin absorption does not contribute to systemic toxicity. In studies with humans, 2‐ethylhexyl acetate did not cause sensitization of the skin; there are no studies with animals available. Damage to the embryo or foetus is unlikely when the MAK value is not exceeded.
Adipinsäure [MAK Value Documentation in German language, 2017]
Authors: Hartwig Andrea ,   MAK‐Kommission
Published: January 2017

Adipic acid [hexanedioic acid]

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has evaluated adipic acid to derive a maximum concentration at the workplace (MAK value), considering all toxicity endpoints.

The critical effect is moderate local irritation as shown with the Draize test in the rabbit eye. Available inhalation studies are limited and not suitable to derive a MAK value. Systemic toxicity only occurs at high doses. In a limited oral 2‐year study the body weight of rats was reduced at 2250 mg/kg body weight/day. The resulting systemic NOAEL is 750 mg/kg body weight/day.

After comparing adipic acid with other solid acids, a MAK value of 2 mg adipic acid/m
3
I has been set in analogy to phosphoric acid, which is considered to be the worst‐case.

As the critical effect is local, adipic acid is assigned to Peak Limitation Category I. In analogy to phosphoric acid, a default excursion factor of 2 is set.

There is no reason to fear damage to the embryo or foetus when the MAK value is observed; thus, the substance is classified in Pregnancy Risk Group C.

Adipic acid is not genotoxic and not carcinogenic. No contact sensitizing effects have been observed. Skin contact is not expected to contribute significantly to systemic toxicity.
n‐Butylacrylat [MAK Value Documentation in German language, 2017]
Authors: Hartwig Andrea ,   MAK‐Kommission
Published: January 2017

n‐Butyl acrylate [butyl prop‐2‐enoate]

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 2 ml/m
3
for n‐butyl acrylate. The critical effect in a two‐year inhalation study with rats was reserve cell hyperplasia with loss of ciliated or olfactory cells at the lowest concentration of 15 ml/m
3
. The lower confidence limit of the benchmark dose for an extra risk of 5% increase of the critical effect incidence (BMDL
05
) of about 3 ml/m
3
, which had been calculated in the previous evaluations, was confirmed. 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. Based on this approach, the equivalent concentration at the workplace is 1.5 ml/m
3
. However, studies in humans to investigate the sensory irritation of n‐butyl acrylate are lacking. As the structurally related ethyl acrylate possesses a RD
50
value as well as subchronic and chronic NOAECs similar to those of n‐butyl acrylate, the NOAEC of 2.5 ml ethyl acrylate/m
3
for sensory irritation in volunteers was used as a read‐across. As the MAK value for ethyl acrylate has been set at 2 ml/m
3
, the MAK value of 2 ml/m
3
for n‐butyl acrylate could be confirmed. In analogy to ethyl acrylate, the assignment of n‐butyl acrylate to Peak Limitation Category I and the excursion factor of 2 were confirmed. The NOAECs for developmental toxicity in rats and mice are sufficiently high so that there is no reason to fear damage to the embryo or foetus when the MAK value is observed. Thus, n‐butyl acrylate continues to be classified in Pregnancy Risk Group C. The substance is marginally clastogenic in vitro but not in vivo after inhalative exposure and was not carcinogenic in a 2‐year inhalation study in rats. There are only a few cases of contact sensitization in humans but there are positive results in local lymph node assays. Data on airway sensitization are still not available. n‐Butyl acrylate continues to be designated with “Sh”. Skin absorption was calculated to contribute significantly to the systemic toxicity and n‐butyl acrylate is designated with an “H”.
Laurinsäure [MAK Value Documentation in German language, 2017]
Authors: Hartwig Andrea ,   MAK‐Kommission
Published: January 2017

Lauric acid [dodecanoic acid]

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated lauric acid, considering all toxicity endpoints.

In an oral 18‐week study no substance‐related effects were observed in rats up to 9000 mg/kg body weight and day. As lauric acid is an organic acid, the respiratory tract might be a target organ; however, inhalation studies are not available. A maximum concentration at the workplace (MAK value) was derived by read across to other solid acids. Lauric acid is irritating to the rabbit eye but less so than succinic and adipic acid. Also the acidity of saturated solutions of lauric acid is less than that of succinic and adipic acid. For the latter acids, a MAK value of 2 mg/m
3
for the inhalable fraction was set like that for phosphoric acid. Phosphoric acid is a stronger acid that is corrosive to the eyes of rabbits. Therefore, in analogy to phosphoric acid as a worst‐case, a MAK value of 2 mg/m
3
for the inhalable fraction is set for lauric acid.

As the MAK value has been derived in analogy to phosphoric acid, lauric acid is also classified in Peak Limitation Category I with an excursion factor of 2.

Lauric acid does not have genotoxic potential. There are no carcinogenicity studies available with lauric acid. Results of a dermal initiation‐promotion study with lauric acid alone were negative; promoting activity was seen only after application of an initiator. Lauric acid is no longer classified as carcinogenic to humans, based on the Commission's evaluation of this type of study.

No significant contribution to systemic toxicity was demonstrated in calculations of dermal absorption. Limited data in animals do not indicate a sensitizing potential for lauric acid.

Developmental toxicity studies are lacking; therefore, lauric acid is assigned to Pregnancy Risk Group D.
Bariumsulfat (alveolengängige Fraktion) [MAK Value Documentation in German language, 2017]
Authors: Hartwig Andrea ,   MAK‐Kommission
Published: January 2017

Barium sulfate [barium (2+); sulfate]

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated barium sulfate. Barium sulfate is a biopersistent granular dust. Therefore, the respirable fraction of barium sulfate dust has been classified in Carcinogen Category 4 and a MAK value of 0.3 mg/m
3
× material density was established for the respirable fraction in analogy to the other biopersistent granular dusts. This classification is based on animal data that showed increased tumor incidences in rats exposed to biopersistent granular dusts in the high dose range. These tumors are regarded to be a consequence of the inflammatory mechanism of action, for which thresholds can be defined. Direct genotoxic effects appear to be of subordinate relevance for the carcinogenicity of biopersistent granular dusts. In analogy to biopersistent granular dusts the Peak Limitation Category II was established for barium sulfate with an excursion factor of 8. Since barium sulfate is not systemically distributed and accumulates only locally in the lungs, no developmental effects due to this dust are expected to occur at the MAK value of 0.3 mg/m
3
× material density (respirable, R‐fraction). Barium sulfate has accordingly been classified in Pregnancy Risk Group C. Barium sulfate is not designated with either “Sa” or “Sh” or “H”.
Terpentinöl [MAK Value Documentation in German language, 2017]
Authors: Hartwig Andrea ,   MAK‐Kommission
Published: January 2017

Turpentine Oil

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has re‐evaluated turpentine oil, considering all toxicity endpoints.

Turpentine oil is a mixture of different terpenes, terpenoids and terpene hydrocarbons, mostly mono and bicyclic monoterpenes like pinene, camphene, dihydropinene, carene or dipentene (limonene) with the main component being alpha‐pinene with 60 to 86%. In 14‐week studies with alpha‐pinene in rats and mice, the critical effect was hyperplasia of the epithelium of the urinary bladder in mice at 100 ml/m3with a no observed adverse effect concentration (NOAEC) of 50 ml/m3. No irritation was observed up to the highest concentration of 400 ml/m3in rats and mice. Taking into account that the systemic NOAEC might be lower after chronic exposure and with the increased breathing volume of workers, a maximum concentration at the workplace (MAK value) of 5 ml/m3was derived for turpentine oil. This concentration is far below 80 ml/m3, at which changes in bronchoalveolar lavage fluid were observed in volunteers after short‐term exposure to a mixture of alpha and beta‐pinene and delta‐carene and which is below the NOAEC for alpha‐pinene of 40 ml/m3for sensory irritation in humans.

The MAK value was derived from a systemic effect; therefore, turpentine oil is classified in Peak Limitation Category II with an excursion factor of 2.

Turpentine oil and its major constituents do not have genotoxic potential. There are no carcinogenicity studies available with turpentine oil or its major components. Results of a dermal initiation‐promotion study with turpentine oil alone were negative; promoting activity was seen only after application of an initiator. Turpentine oil is no longer classified as carcinogenic to humans, based on the Commission's evaluation of this type of study.

A significant contribution to systemic toxicity was demonstrated in a model calculation of dermal absorption and turpentine oil is designated with an “H”. Due to the data described in the evaluation of 1996, turpentine oil continues to be designated with an “Sh”.

Valid developmental toxicity studies are lacking; therefore, turpentine oil is assigned to Pregnancy Risk Group D.
Peak limitation: Limitation of exposure peaks and short‐term exposures [MAK Value Documentation, 2011]
Authors: Hartwig A. ,   MAK Commission
Published: January 2017

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area sets maximum concentrations for chemicals in the work place air (MAK value). The MAK value is defined as a time‐weighted average concentration for 8 hours per day and assuming on average a 40‐hour work week. The Commission has defined criteria to limit exposure peaks which commonly occur at the work place to avoid possible adverse health effects. Peak exposures are limited by an excursion factor, which, when multiplied with the MAK value, gives the maximum permissible peak concentration as average of a sampling period of 15 minutes. Such excursions are restricted to 4 times per shift and should be spaced at least by a one‐hour interval. Compounds which act primarily locally, i.e. irritants of eyes or airways as well as respiratory sensitizers, are grouped into Peak Limitation Category I. For these chemicals, the concentration is decisive for the effects. The default excursion factor is 1, if human data on local irritation or suitable long‐term animal studies are available, a higher factor can be set. An excursion factor of 1 means, that at any time during the shift, the 15‐minute average must not exceed the MAK value. In specific cases, a momentary value can be set, i.e. a concentration that must not be exceeded at any time. When systemic effects are critical, the compound is assigned to Peak Limitation Category II. As default, it is assumed that the systemic maximum concentration is exposure limiting. The impact of an exposure peak on the maximum concentration is dependent on the half‐life of the chemical. The default excursion factor is 2, if data on the half‐life of the chemical or its critical metabolite are not available. When the half‐life is known, corresponding excursion factors have been estimated with a kinetic first‐order model to limit the increase of the maximum systemic concentration to less than 25%. For half‐lives ≥ 8 hours, 4–8 hours, 1–4 hour and < 1 hour the respective excursion factors are 8, 4, 2 and 1. When it is shown that the critical effect is not caused by the concentration (C
max
) but by the concentration‐time product (area under the curve), the excursion factor can be up to 8, which is the maximum possible excursion factor. However, the resulting short‐term concentration must not lead to irritation or narcotic effects. Regardless of the magnitude of the excursion factor, the MAK value, i.e. the average over 8 hours, must not be exceeded.
Chiral Titanium Coordination Assemblies: Robust Cooperative Self‐Supported Catalysts for Asymmetric Ring Opening of meso‐Epoxides with Aliphatic Amines
Authors: Sun Zheming , Chen Jiangbo , Liu Yaoqi , Tu Tao
Published: January 2017

By utilizing the oxygen bridge in dimeric μ‐oxo‐titanium‐salen complexes as an efficient cross‐linkage, a series of robust chiral titanium coordination assemblies has been successfully fabricated with the ditopic bridging ligands derived from BINOL and salen derivatives via coordination polymerization, which are fully characterized by IR, elemental analysis, XRD and microscopic studies. Because of their insolubility in most organic solvents and water, these metal‐organic assemblies can successfully function as robust self‐supported chiral catalysts, allowing an asymmetric ring opening (ARO) of meso‐epoxides with aliphatic amines. Remarkably, owing to the linkage effects and the cooperation of two kinds of chiral titanium moieties in the metal‐organic assemblies, the self‐supported chiral catalysts demonstrate extremely high stability. They not only show high tolerance towards various meso‐epoxides and nucleophilic aliphatic amines, but also can be reused in more than 20 runs without obvious metal leaching and loss in yields and enantioselectivities. Furthermore, the self‐supported catalyst accomplished a one‐pot tandem olefin epoxidation and ARO of an epoxide sequence starting from the olefin, 30% hydrogen peroxide and benzylamine. In marked contrast, the reaction failed to work when using the two corresponding homogeneous catalysts under identical reaction conditions. Good yields and enantioselectivities were obtained by the robust self‐supported catalyst, which clearly indicates the cooperative effects between two chiral moieties within the metal‐organic assemblies. The two catalytic centers can perform their own duties without interference and this further supports our strategy for the self‐supported catalyst design.

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One‐Pot Palladium‐Catalyzed Cross‐Coupling Treble of Borylation, the Suzuki Reaction and Amination
Authors: Jong Howard , Eey Stanley T.‐C. , Lim Yee Hwee , Pandey Sangeeta , Iqbal Nurul Azmah Bte , Yong Fui Fong , Robins Edward G. , Johannes Charles W.
Published: January 2017

A methodology for a sequential palladium‐catalyzed cross‐coupling procedure consisting of borylation, the Suzuki reaction and amination has been developed for the assembly of molecules with multi‐aryl backbones. The linchpin of this development is the meta‐terarylphosphine ligand, Cy*Phine, which has been employed as an air‐ and moisture‐stable precatalyst, Pd(Cy*Phine)2Cl2, to improve the efficiency of one‐pot borylation–Suzuki reactions. Additionally, the reactivity of the Pd‐Cy*Phine system could be tuned to furnish a one‐pot, borylation–Suzuki reaction–amination (BSA) cross‐coupling treble. The methodology successfully integrated complementary conditions for three distinctly different and modular reactions. Average yields of 74–94% could be achieved for each segment that cumulatively afforded 50–84% yield over the entire three‐step sequence in a single pot.

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Cooperative Electrocatalytic and Chemoselective Alcohol Oxidation by Shvo's Catalyst
Authors: Lybaert Jeroen , Trashin Stanislav , Maes Bert U. W. , De Wael Karolien , Abbaspour Tehrani Kourosch
Published: January 2017

A new electrocatalytic conversion of alcohols to ketones and aldehydes was developed based on an electrochemical study of Shvo's complex. The oxidation of secondary alcohols was efficiently performed under mild conditions using a catalytic amount of Shvo's catalyst, in combination with a sub‐stoichiometric amount of 2,6‐dimethoxy‐1,4‐benzoquinone in N,N‐dimethylformamide at 80 °C. The hydroquinone thus formed is continuously reoxidized with the aid of an electrochemical device. Excellent yields for different ketones, aromatic as well as aliphatic and α,β‐unsaturated ketones, are obtained. In addition, chemoselectivity towards oxidation of the secondary alcohol is achieved when converting vicinal diols such as 1,2‐octanediol and 1,2‐decanediol.

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Silver‐Catalyzed Carbon‐Phosphorus Functionalization for Polyheterocycle Formation
Authors: Liu Jianming , Zhao Shanshan , Song Weiwei , Li Rong , Guo Xinyu , Zhuo Kelei , Yue Yuanyuan
Published: January 2017

Polyheterocycle construction with high diastereoselectivity by utilizing a radical process is still problematic. In this communication, a silver‐catalyzed carbon‐phosphorus functionalization for polyheterocycle formation is described that furnishes good diastereoselectivity. Various substituted 1‐(1H‐indol‐1‐yl)‐3‐phenylprop‐2‐en‐1‐ones and phosphine oxides were suitable for this transformation. This work avoids the installation of direct functional groups and thus makes full use of shorter and more efficient synthetic processes. Preliminary mechanistic investigations indicate that phosphorus radicals are involved by attacking the α‐position of α,β‐unsaturated carbonyl compounds to generate the desired products.

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A predictive model for obstructive sleep apnea and Down syndrome
Authors: Skotko Brian G. , Macklin Eric A. , Muselli Marco , Voelz Lauren , McDonough Mary Ellen , Davidson Emily , Allareddy Veerasathpurush , Jayaratne Yasas S. N. , Bruun Richard , Ching Nicholas , Weintraub Gil , Gozal David , Rosen Dennis
Published: January 2017

Obstructive sleep apnea (OSA) occurs frequently in people with Down syndrome (DS) with reported prevalences ranging between 55% and 97%, compared to 1–4% in the neurotypical pediatric population. Sleep studies are often uncomfortable, costly, and poorly tolerated by individuals with DS. The objective of this study was to construct a tool to identify individuals with DS unlikely to have moderate or severe sleep OSA and in whom sleep studies might offer little benefit. An observational, prospective cohort study was performed in an outpatient clinic and overnight sleep study center with 130 DS patients, ages 3–24 years. Exclusion criteria included previous adenoid and/or tonsil removal, a sleep study within the past 6 months, or being treated for apnea with continuous positive airway pressure. This study involved a physical examination/medical history, lateral cephalogram, 3D photograph, validated sleep questionnaires, an overnight polysomnogram, and urine samples. The main outcome measure was the apnea‐hypopnea index. Using a Logic Learning Machine, the best model had a cross‐validated negative predictive value of 73% for mild obstructive sleep apnea and 90% for moderate or severe obstructive sleep apnea; positive predictive values were 55% and 25%, respectively. The model included variables from survey questions, medication history, anthropometric measurements, vital signs, patient's age, and physical examination findings. With simple procedures that can be collected at minimal cost, the proposed model could predict which patients with DS were unlikely to have moderate to severe obstructive sleep apnea and thus may not need a diagnostic sleep study.
Rhodium‐Catalyzed Decarbonylative Borylation of Aromatic Thioesters for Facile Diversification of Aromatic Carboxylic Acids
Authors: Ochiai Hidenori , Uetake Yuta , Niwa Takashi , Hosoya Takamitsu
Published: January 2017

Transformation of aromatic thioesters into arylboronic esters was achieved efficiently using a rhodium catalyst. The broad functional‐group tolerance and mild conditions of the method have allowed for the two‐step decarboxylative borylation of a wide range of aromatic carboxylic acids, including commercially available drugs.
General Enantioselective C−H Activation with Efficiently Tunable Cyclopentadienyl Ligands
Authors: Jia Zhi‐Jun , Merten Christian , Gontla Rajesh , Daniliuc Constantin G. , Antonchick Andrey P. , Waldmann Herbert
Published: January 2017

Cyclopentadienyl (Cp) ligands enable efficient steering of various transition‐metal‐catalyzed transformations, in particular enantioselective C−H activation. Currently only few chiral Cp ligands are available. Therefore, a conceptually general approach to chiral Cp ligand discovery would be invaluable as it would enable the discovery of applicable Cp ligands and to efficiently and rapidly vary and tune their structures. Herein, we describe the three‐step gram‐scale synthesis of a structurally diverse and widely applicable chiral Cp ligand collection (JasCp ligands) with highly variable and adjustable structures. Their modular nature and their amenability to rapid structure variation enabled the efficient discovery of ligands for three enantioselective RhIII‐catalyzed C−H activation reactions, including one unprecedented transformation. This novel approach should enable the discovery of efficient chiral Cp ligands for various further enantioselective transformations.
Photoproduction of Hydrogen by Decamethylruthenocene Combined with Electrochemical Recycling
Authors: Rivier Lucie , Peljo Pekka , Vannay Laurent A. C. , Gschwend Grégoire C. , Méndez Manuel A. , Corminboeuf Clémence , Scanlon Micheál D. , Girault Hubert H.
Published: January 2017

The photoinduced hydrogen evolution reaction (HER) by decamethylruthenocene, Cp2*RuII (Cp*=C5Me5), is reported. The use of a metallocene to photoproduce hydrogen is presented as an alternative strategy to reduce protons without involving an additional photosensitizer. The mechanism was investigated by (spectro)electrochemical and spectroscopic (UV/Vis and 1H NMR) measurements. The photoactivated hydride involved was characterized spectroscopically and the resulting [Cp2*RuIII]+ species was electrochemically regenerated in situ on a fluorinated tin oxide electrode surface. A promising internal quantum yield of 25 % was obtained. Optimal experimental conditions— especially the use of weakly coordinating solvent and counterions—are discussed.
Dual Fluorescent‐ and Isotopic‐Labelled Self‐Assembling Vancomycin for in vivo Imaging of Bacterial Infections
Authors: Yang Cuihong , Ren Chunhua , Zhou Jie , Liu Jinjian , Zhang Yumin , Huang Fan , Ding Dan , Xu Bing , Liu Jianfeng
Published: January 2017

The increase of bacterial resistance demands rapid and accurate diagnosis of bacterial infections. Biosurface‐induced supramolecular assembly for diagnosis and therapy has received little attention in detecting bacterial infections. Herein we present a dual fluorescent‐nuclear probe based on self‐assembly of vancomycin (Van) on Gram‐positive bacteria for imaging bacterial infection. A Van‐ and rhodamine‐modified peptide derivative (Rho‐FF‐Van), as the imaging agent, binds to the terminal peptide of the methicillin‐resistant staphylococcus aureus (MRSA) and self‐assembles to form nanoaggregates on the surface of MRSA. In an in vivo myositis model, Rho‐FF‐Van results in a significant increased fluorescence signal at the MRSA infected site. Radiolabeled with iodine‐125, Rho‐FF‐Van shows strong radioactive signal in the MRSA‐infected lungs in a murine model. This novel dual fluorescent and nuclear probe promises a new way for in vivo imaging of bacterial infections.
High‐Performance Organic Solar Cells Based on a Non‐Fullerene Acceptor with a Spiro Core
Authors: Sun Hua , Sun Po , Zhang Cong , Yang Yingguo , Gao Xingyu , Chen Fei , Xu Zongxiang , Chen Zhi‐Kuan , Huang Wei
Published: January 2017

Derived from perylenediimide (PDI) building blocks, 3D PDI molecules are considered as a type of promising structure to overcome molecular aggregation, thus improving the performance of organic solar cells. Herein, we report a novel PDI‐based derivative, SCPDT‐PDI4, with four PDI units connected to a unique spiro core. Attributed to this novel molecular design, SCPDT‐PDI4 exhibits a rigid 3D structure, in which the aggregation tendency of PDI chromophores could be effectively attenuated. Additionally, strong intramolecular charge transfer and high charge mobility are achieved due to the well‐conjugated structure and electron‐rich property of SCPDT. Therefore, fullerene‐free organic solar cells based on SCPDT‐PDI4 and PTB7‐Th achieve a remarkable high efficiency of 7.11 %. Such an excellent result demonstrates the opportunity of SCPDT to be a promising building block for non‐fullerene acceptors.
Sustainable design of biorefinery processes: existing practices and new methodology
Authors: Julio Remi , Albet Joël , Vialle Claire , Vaca‐Garcia Carlos , Sablayrolles Caroline
Published: January 2017

Nowadays, eco‐designing products is increasingly practiced. The next challenge for sustainability is to optimize production processes. Biorefineries are particularly concerned with this improvement, because they use renewable resources. To identify the contribution of transformation processes to the overall environmental impacts, Life Cycle Assessment (LCA) appears as the adequate method. A literature review highlights that LCA is mainly performed on biorefineries to compare biomass feedstocks between them and to a fossil reference. Another part of environmental LCA compares the impacts of different processing routes. Nevertheless, these evaluations concern already designed processes. Generally, processes are considered as a unique operation in assessments. However, some criteria like operating can notably modify environmental burdens. The eco‐design of biorefinery processes can be guided by coupling process simulation to LCA. This method has been emerging in the chemical sector in recent years. Consequently, this paper proposes a new methodological approach to assessing the complete sustainability of biorefinery processes, since its first design stages. In addition to coupling process simulation and environmental LCA, the other pillars of sustainability will be assessed. Indeed, Life Cycle Costing and Social Life Cycle Assessment can be performed to obtain an integrated methodological framework. The simultaneous optimization of the environmental, economic, and social performances of the process can lead to antagonist ways of improving. Consequently, compromises should be realized. Thereby, the multi‐objective optimization can be accomplished by a metaheuristic method supported by a decision‐making tool. Finally, the main limits of this method and some perspectives and ways for improving are discussed. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd
Measurement analysis of two radials with a common‐origin point and its application
Authors: Liu Zhenyao , Yang Jidong , Zhu Weiwei , Zhou Shang , Tan Xuanping
Published: January 2017

In spectral analysis, a chemical component is usually identified by its characteristic spectra, especially the peaks. If two components have overlapping spectral peaks, they are generally considered to be indiscriminate in current analytical chemistry textbooks and related literature. However, if the intensities of the overlapping major spectral peaks are additive, and have different rates of change with respect to variations in the concentration of the individual components, a simple method, named the ‘common‐origin ray’, for the simultaneous determination of two components can be established. Several case studies highlighting its applications are presented.
Peptide Paratope Mimics of the Broadly Neutralizing HIV‐1 Antibody b12
Authors: Haußner Christina , Damm Dominik , Nirschl Sandra , Rohrhofer Anette , Schmidt Barbara , Eichler Jutta
Published: January 2017

The broadly neutralizing HIV‐1 antibody b12 recognizes the CD4 binding site of the HIV‐1 envelope glycoprotein gp120 and efficiently neutralizes HIV‐1 infections in vitro and in vivo. Based on the 3D structure of a b12⋅gp120 complex, we have designed an assembled peptide (b12‐M) that presents the parts of the three heavy‐chain complementarity‐determining regions (CDRs) of b12, which contain the contact sites of the antibody for gp120. This b12‐mimetic peptide, as well as a truncated peptide presenting only two of the three heavy‐chain CDRs of b12, were shown to recognize gp120 in a similar manner to b12, as well as to inhibit HIV‐1 infection, demonstrating functional mimicry of b12 by the paratope mimetic peptides.
Slowly progressive invasive rhino‐orbito‐cerebral aspergillosis: case report and literature review
Authors: de Martin Truzzi Giselle , Furlan Pauna Henrique , Moreira Hazboun Igor , Benedick Coimbra Igor , Sakuma Emerson Taro Inoue , Barreto Icléia Siqueira , Chone Carlos Takahiro , Sakano Eulalia
Published: January 2017

Key Clinical Message

This is a report of a patient with aspergillosis infection, which was thought to be a tumoral lesion during its investigation. This is not a common disease in Western countries, and this report should increase our awareness for differential diagnosis of nasal masses. Early diagnosis is desired in order to increase the survival rates.
Ring‐Opening Reaction of Furfural and Tetrahydrofurfuryl Alcohol on Hydrogen‐Predosed Iridium(1 1 1) and Cobalt/Iridium(1 1 1) Surfaces
Authors: Wan Weiming , Jenness Glen R. , Xiong Ke , Vlachos Dionisios G. , Chen Jingguang G.
Published: January 2017

The ring‐opening of furfural is crucial for its conversion into value‐added chemicals such as 1,5‐pentanediol (1,5‐PeD), an important polymer precursor. Ir‐based catalysts have shown activity in ring‐opening reactions, and the use of an oxophilic metal additive is reported to be beneficial. To better understand the effect of an oxophilic metal on Ir for the opening of the furan ring, a combination of DFT calculations and experimental surface science studies were performed to investigate the ring‐opening of furfural and tetrahydrofurfuryl alcohol. The experimental results suggest that Co/Ir(1 1 1) has a higher ring‐opening activity for an unsaturated furan ring, however, the difference in activities between Ir and Co/Ir(1 1 1) is insignificant for a saturated furan ring. The DFT results reveal that Co/Ir(1 1 1) has a stronger interaction with an unsaturated furan ring than Ir(1 1 1); both surfaces show a weaker interaction with the saturated furan ring, which causes the lower ring‐opening activity than that of furfural.