bluuebunny/crossref_metadata_2025 huggingface dataset:
The genesis of Typhoon Nuri as observed during the Tropical Cyclone Structure 2008 (TCS-08) field experiment – Part 3: Dynamics of low-level spin-up during the genesis
Authors: Lussier III L. L. , Montgomery M. T. , Bell M. M.
Published: August 2014

Abstract. Aircraft reconnaissance data collected during the Tropical Cyclone Structure 2008 field campaign are used to examine further kinematical, dynamical, and thermodynamical aspects of the genesis of Typhoon Nuri. Data from the first two missions into the pre-Nuri disturbance document the transition from a tropical wave to a tropical depression. Dropwindsonde-derived tangential wind profiles at several radii from the low-level circulation center indicate that the magnitude of low-level circulation increases and that the corresponding tangential velocity maximum moves inward from the first to second reconnaissance mission. To compliment these findings, a three-dimensional variational analysis incorporating both dropwindsonde and aircraft Doppler radar data is conducted. These data are used to perform circulation tendency calculations at multiple distances from the low-level circulation center. The results demonstrate a net spin-up of the system-scale circulation in the low levels near the center and in the outer regions of the recirculating Kelvin cat's eye circulation. In these regions, the spin-up tendency due to the influx of cyclonic absolute vorticity exceeds the frictional spin-down tendency for both Nuri missions. The system-scale spin-up is found to be accompanied by areas of low-level vorticity concentration through vortex-tube stretching associated with cumulus convection. The areal coverage and intensity of these high-vorticity regions increase between the first and second Nuri missions. The findings of this study are consistent in some respects to the Nuri observational analysis carried out by Raymond and López-Carrillo (2011), but differ in their suggested key results and related scientific implications that the pre-Nuri disturbance was spinning down in the planetary boundary layer on the first day of observations. The findings herein strongly support a recent tropical cyclogenesis model positing that the Kelvin cat's eye circulation of the parent wave-like disturbance provides a favorable environment for convective vorticity organization and low-level spin-up on the mesoscale.
Sources and geographical origins of fine aerosols in Paris (France)
Authors: Bressi M. , Sciare J. , Ghersi V. , Mihalopoulos N. , Petit J.-E. , Nicolas J. B. , Moukhtar S. , Rosso A. , Féron A. , Bonnaire N. , Poulakis E. , Theodosi C.
Published: August 2014

Abstract. The present study aims at identifying and apportioning fine aerosols to their major sources in Paris (France) – the second most populated "larger urban zone" in Europe – and determining their geographical origins. It is based on the daily chemical composition of PM2.5 examined over 1 year at an urban background site of Paris (Bressi et al., 2013). Positive matrix factorization (EPA PMF3.0) was used to identify and apportion fine aerosols to their sources; bootstrapping was performed to determine the adequate number of PMF factors, and statistics (root mean square error, coefficient of determination, etc.) were examined to better model PM2.5 mass and chemical components. Potential source contribution function (PSCF) and conditional probability function (CPF) allowed the geographical origins of the sources to be assessed; special attention was paid to implement suitable weighting functions. Seven factors, namely ammonium sulfate (A.S.)-rich factor, ammonium nitrate (A.N.)-rich factor, heavy oil combustion, road traffic, biomass burning, marine aerosols and metal industry, were identified; a detailed discussion of their chemical characteristics is reported. They contribute 27, 24, 17, 14, 12, 6 and 1% of PM2.5 mass (14.7 μg m−3) respectively on the annual average; their seasonal variability is discussed. The A.S.- and A.N.-rich factors have undergone mid- or long-range transport from continental Europe; heavy oil combustion mainly stems from northern France and the English Channel, whereas road traffic and biomass burning are primarily locally emitted. Therefore, on average more than half of PM2.5 mass measured in the city of Paris is due to mid- or long-range transport of secondary aerosols stemming from continental Europe, whereas local sources only contribute a quarter of the annual averaged mass. These results imply that fine-aerosol abatement policies conducted at the local scale may not be sufficient to notably reduce PM2.5 levels at urban background sites in Paris, suggesting instead more coordinated strategies amongst neighbouring countries. Similar conclusions might be drawn in other continental urban background sites given the transboundary nature of PM2.5 pollution.
A negative feedback between anthropogenic ozone pollution and enhanced ocean emissions of iodine
Authors: Prados-Roman C. , Cuevas C. A. , Fernandez R. P. , Kinnison D. E. , Lamarque J.-F. , Saiz-Lopez A.
Published: August 2014

Abstract. Naturally emitted from the oceans, iodine compounds efficiently destroy atmospheric ozone and reduce its positive radiative forcing effects in the troposphere. Emissions of inorganic iodine have been experimentally shown to depend on the deposition to the oceans of tropospheric ozone, whose concentrations have significantly increased since 1850 as a result of human activities. A chemistry-climate model is used herein to quantify the current ocean emissions of inorganic iodine and assess the impact that the anthropogenic increase of tropospheric ozone has had on the natural cycle of iodine in the marine environment since pre-industrial times. Our results indicate that the human-driven enhancement of tropospheric ozone has doubled the oceanic inorganic iodine emissions following the reaction of ozone with iodide at the sea surface. The consequent build-up of atmospheric iodine, with maximum enhancements of up to 70% with respect to preindustrial times in continental pollution outflow regions, has in turn accelerated the ozone chemical loss over the oceans with strong spatial patterns. We suggest that this ocean–atmosphere interaction represents a negative geochemical feedback loop by which current ocean emissions of iodine act as a natural buffer for ozone pollution and its radiative forcing in the global marine environment.
Comparing the cloud vertical structure derived from several methods based on radiosonde profiles and ground-based remote sensing measurements
Authors: Costa-Surós M. , Calbó J. , González J. A. , Long C. N.
Published: August 2014

Abstract. The cloud vertical distribution and especially the cloud base height, which is linked to cloud type, are important characteristics in order to describe the impact of clouds on climate. In this work, several methods for estimating the cloud vertical structure (CVS) based on atmospheric sounding profiles are compared, considering the number and position of cloud layers, with a ground-based system that is taken as a reference: the Active Remote Sensing of Clouds (ARSCL). All methods establish some conditions on the relative humidity, and differ in the use of other variables, the thresholds applied, or the vertical resolution of the profile. In this study, these methods are applied to 193 radiosonde profiles acquired at the Atmospheric Radiation Measurement (ARM) Southern Great Plains site during all seasons of the year 2009 and endorsed by Geostationary Operational Environmental Satellite (GOES) images, to confirm that the cloudiness conditions are homogeneous enough across their trajectory. The perfect agreement (i.e., when the whole CVS is estimated correctly) for the methods ranges between 26 and 64%; the methods show additional approximate agreement (i.e., when at least one cloud layer is assessed correctly) from 15 to 41%. Further tests and improvements are applied to one of these methods. In addition, we attempt to make this method suitable for low-resolution vertical profiles, like those from the outputs of reanalysis methods or from the World Meteorological Organization's (WMO) Global Telecommunication System. The perfect agreement, even when using low-resolution profiles, can be improved by up to 67% (plus 25% of the approximate agreement) if the thresholds for a moist layer to become a cloud layer are modified to minimize false negatives with the current data set, thus improving overall agreement.
Hydrological drought forecasting and skill assessment for the Limpopo river basin, Southern Africa
Authors: Trambauer P. , Werner M. , Winsemius H. C. , Maskey S. , Dutra E. , Uhlenbrook S.
Published: August 2014

Abstract. Ensemble hydrological predictions are normally obtained by forcing hydrological models with ensembles of atmospheric forecasts produced by Numerical weather prediction models. To be of practical value to water users, such forecasts should not only be sufficiently skilful, they should also provide information that is relevant to the decisions end users make. The semi-arid Limpopo basin in Southern Africa has experienced severe droughts in the past, resulting in crop failures, high economic losses and the need for humanitarian aid. In this paper we address the seasonal prediction of hydrological drought for the Limpopo river basin by testing three proposed forecasting systems (FS) that can provide operational guidance to dam operators and water managers within the basin at the seasonal time scale. All three FS include a distributed hydrological model of the basin, and are forced with either (i) a global atmospheric model forecast (ECMWF seasonal forecast system – S4), (ii) the commonly applied Ensemble Streamflow Prediction approach (ESP) using resampled historical data, or (iii) a conditional ESP approach (ESPcond), which is conditional on the ENSO signal. We determine the skill of the three systems in predicting drought indices and streamflow. We also assess the skill of the model in predicting indicators that are meaningful to the local end users in the basin. FS_S4 shows moderate skill for all lead times (3, 4, and 5 months) and aggregation periods. FS_ESP also performs better than climatology for the shorter lead times, but with a lower skill than FS_S4. FS_ESPcond shows skill in between the other two FS, though its skill is shown to be more robust. The skills of FS_ESP and FS_ESPcond reduce rapidly with increasing lead time. Both FS_S4 and FS_ESPcond show good potential for seasonal hydrological drought forecasting in the Limpopo river basin, which is encouraging in the context of providing better operational guidance to water users.
Forest harvesting is associated with increased landslide activity during an extreme rainstorm on Vancouver Island, Canada
Authors: Goetz J. N. , Guthrie R. H. , Brenning A.
Published: August 2014

Abstract. Safe operations of forest practices in mountainous regions require effective development planning to mitigate hazards posed by landslides. British Columbia, Canada, has for the past two decades implemented landslide risk management policies aimed at reducing the impacts of the forest industry on landslides; it is required that timber harvesting sites are evaluated for their potential or existing impacts on terrain stability. Statistical landslide susceptibility modelling can enhance this evaluation by geographically highlighting potential hazardous areas. In addition, these statistical models can also improve our understanding of regional landslide controlling factors. The purpose of this research was to explore the regional effects of forest harvesting activities, topography, precipitation and geology on landslides initiated during an extreme rainfall event in November 2006 on Vancouver Island, British Columbia. These effects were analysed with a nonparametric statistical method, the generalized additive model (GAM). Although topography was the strongest predictor of landslide initiation, low density forest interpreted as regrowth areas and proximity to forest service roads were jointly associated with a six- to nine-fold increase in the odds of landslide initiation, while accounting for other environmental cofounders. This result highlights the importance of continuing proper landslide risk management to control the effects of forest practices on landslide initiation.
Soil physical quality changes under different management systems after 10 years in Argentinian Humid Pampa
Authors: Costa J. L. , Aparicio V. C. , Cerda A.
Published: August 2014

Abstract. The Argentinian Humid Pampa extends over about 60 million ha, 90% of which are agricultural lands. The southeast of the Buenos Aires Province is part of the Humid Pampa (1 206 162 ha). The main crops are wheat, sunflower, corn and soybean. The management systems used in the area are: moldboard plow (MP), chisel plow (CP) and no-till (NT). Excessive soil cultivation under MP causes decreases in the soil organic carbon content (SOC). Adopting NT may reduce the effects of intensive agriculture, through the maintenance and accumulation of SOC. However, the soil compaction under NT causes degradation of the soil structure, reduces the soil water availability and reduces the soil hydraulic conductivity. We evaluated the evolution of the soil physical parameters in three management systems. After 10 years of experiments in four farmers' fields, we found that: soil bulk density was significantly higher under NT. The change in mean weight diameter (CMWD) of aggregates increased as the management system became more intensive. We did not find significant differences in time and management systems in hydraulic conductivity at tension (h)0 cm and h=20 cm. The reduction in total porosity under NT is mainly a product of a reduction in the percentage of mesopores in the soil. Time had no statistically significant effect on the SOC content. The management system did not affect the yields of crop. In this work, the results indicate a modification of some soil physical parameters (porosity, near-saturated hydraulic conductivity, soil structure) due to uninterrupted agricultural production.
Herziening Tabaksrichtlijn
Authors: Fröger R.A. , de Weers K.
Published: August 2014

Herziening Tabaksrichtlijn

Op 14 maart 2014 is de nieuwe Tabaksrichtlijn 2014/40/EU (hierna: de Richtlijn) vastgesteld. De nieuwe Tabaksrichtlijn brengt een ingrijpende wijziging op het gebied van de productie en distributie van tabaksproducten met zich mee. Op 20 mei 2016 moet de Richtlijn in de Nederlandse wetgeving zijn geïmplementeerd. In deze bijdrage worden de belangrijkste kenmerken van de Richtlijn besproken en wordt kort ingegaan op de gevolgen voor de Nederlandse rechtsorde.

Richtlijn 2014/40/EU van het Europees Parlement en de Raad van 3 april 2014 betreffende de onderlinge aanpassing van de wettelijke en bestuursrechtelijke bepalingen van de lidstaten inzake de productie, de presentatie en de verkoop van tabaks- en aanverwante producten en tot intrekking van Richtlijn 2001/37/EG, Pb. EU 2014, L 127/1.
Effect of seed pickling without pesticides on the growth of Penicillium expansum and patulin biosynthesis
Authors: Florianowicz Teresa
Published: August 2014

The effect of seed pickling without pesticides recommended by the Research Institute of Vegetable Crops in Skierniewice in the method of intensive environment-friendly cultivation on the growth and patulin biosynthesis of patulinogenous microfungus Penicillim expansum, was investigated. A complete inhibition of patulin biosynthesis at 6% and no growth at 8% concentration of the dressing in in vitro conditions was revealed.
The influence of Hypholoma fasciculare and Phlebiopsis gigantea on the growth of Heterobasidion annosum in vitro
Authors: Łakomy Piotr , Zieniewicz Joanna , Świdkiewicz Tomasz
Published: August 2014

The influence of two saprotrophes — isolates of Hypholoma fasciculare and Phlebiopsis gigantea on the growth of thirty three root pathogen strains — Heterobasidion annosum was analysed. Two methods were used. The different reaction in paired cultures among saprotrophe and pathogen isolates suggest, that one isolate of H. annosum is not enough to study the interaction between this pathogen and saprophytes in vitro irrespective of the method used.
Some zygomycetous fungi new to Poland
Authors: Wrzosek Marta , Gajowniczek Zygmunt
Published: August 2014

In the years 1996-1997 the authors studied soil and coprophilic fungi. During thc study the following species of zygomycetous fungi were recorded the first time from Poland: Absidia parricida, Dimargaris cristalligena, Mortierella gamsii, Mortierella sclerotiella and Spinalia radians. The present data are based on material collected by the authors from many regions of Poland, among others: in Słowiński National Park, Tatrzański National Park, Wielkopolski National Park, Wigierski National Park and Woliński National Park.
Mycelial culture of Xerocomus chrysenteron and its metabolites
Authors: Kohlmünzer Stanisław , Węgiel Janina , Grzybek Jan
Published: August 2014

Subject to analysis was mycelial culture of Xerocomus chrysenteron and its metabolites which night be of pharmaceutical on toxicological interest. Several groups of metabolites were analysed: steroids, fatty acids, indole desiratives, aminoacid, sugars - using chromatographic analytical methods. Amony others soma interesting idolic substances were detected.
Macromycetes of the Kręgi Kamienne nature-archaeological reserve in the Bory Tucholskie (NW Poland)
Authors: Ławrynowicz Maria , Szkodzik Jarosław
Published: August 2014

In the years 1994-1995 mycocoenological investigations in the Leucobryo-Pinetum and Calluno-Genistetum associations on permanent plots were carried out. The survey of macrofungal species and discussion of results arę given in the paper.
Micromyces bulbosus sp. nov
Authors: Kadłubowska Joanna Z.
Published: August 2014

A new species Micromyces bulbosus Kadłubowska is described and illustrated from a puddle in the forest reserve Wolbórka (near Łódź~). This species differs from the others by the dimensions of the prosorus, sorus and resting spore, as well as shape and length of spines, also reticulate outer surface of prosorus.
Exploring the Veterinary Literature: A Bibliometric Methodology for Identifying Interdisciplinary and Collaborative Publications
Authors: Page Jessica R. , Moberly Heather K. , Youngen Gregory K. , Hamel Barbara J.
Published: August 2014

Veterinary medical research traditionally focuses on animal health and wellness; however, research activities at veterinary colleges extend beyond these traditional areas. In this study, we analyzed eleven years of Web of Knowledge-indexed peer-reviewed articles from researchers at the twenty-eight United States American Veterinary Medical Association (AVMA) accredited veterinary colleges. We had three goals in assessing the published literature of veterinary college researchers. First, we identified a list of journals and research areas outside veterinary medicine in which veterinary researchers publish. This list of journals can be customized to identify those most essential at each institution. Second, we identified collaborative work by veterinary researchers across disciplines and institutions. Using textual analysis tools and visualizations helped us illustrate and clarify these data. Last, we developed a methodology for defining an interdisciplinary serials list outside a subject core that can be customized for specific institutions and subject areas.
How Motherhood Triumphs Over Trauma Among Mothers With Children From Genocidal Rape in Rwanda
Authors: Kantengwa Odeth
Published: August 2014

Rape is a common occurrence during genocide and the presence of children born as a result of rape poses a challenge to post-genocide recovery processes. This paper treats mothers of children born as a result of genocidal rape during the 1994 Genocide against the Tutsi as a separate category of survivors and explores the contribution of a positive embrace of motherhood in their recovery. It is based upon a study that included fourteen women from Kigali city, Karongi District in the Western Province and Huye District in the Southern Province. Qualitative analysis of individual interviews and focus groups provided a means to explore in-depth the perceptions of mothers and the value of motherhood. It was found that mothers of children of rape experienced challenges raising their children, especially in the early stages of parenting. Social stigma related to rape and children born of rape created challenges, as did the lack of psychosocial resources for the women, particularly when faced with disclosing paternity to the children. However, despite these and other difficulties, motherhood played a positive role for many women, often providing a reason to live again after the genocide. These findings show that positive experiences of motherhood can be key to the recovery of survivors of genocidal rape in Rwanda and points to future directions for research and health promotion among populations affected by conflict-related sexual violence.
Preparation and Performance of Catalytic Hollow Fibre Membranes for Hydrogenation Reduction of Nitrites in Water
Authors: Tong Gonghe , Song Jian , Wang Peng , Zhao Hongyong , Tan Xiaoyao
Published: August 2014

Porous Al2O3 hollow fiber membranes have been fabricated via a phase inversion – sintering technique. Pd-loaded carbon nanotubes (CNTs) are formed inside the hollow fibre wall by the catalytic decomposition of methane over Fe particles, followed by impregnation and reduction with hydrogen to form catalytic hollow fibre membranes. Hydrophobic modification of the hollow fibres is conducted by gas permeable polymeric coating. The resultant hollow fibre membranes exhibit highly catalytic activity to the hydrogenation reduction of nitrites in aqueous solution. Hollow fibre membrane reactors are assembled for nitrite hydrogenation by pumping nitrite solution into the tube side and introducing hydrogen countercurrently to the shell side of the reactor. The nitrite removal in the hollow fibre membrane reactors increases with the operation temperature and the hydrogen feed concentration at lower hydrogen partial pressures, but less influenced by the hydrogen feed concentration when it is higher than 50%. A higher nitrite concentration favors the nitrite hydrogenation reaction but lowers the nitrite removal efficiency.
Academic Probation: An Empirical Study of Private University Students
Authors: Ahmed Jashim Uddin , Chowdhury Md. Humayun Kabir , Rahman Sheehan , Talukder A K M Mominul Haque
Published: August 2014

This study examines the factors contributing to academic probation in university settings and highlights the problems that students encounter in higher education institutions in Bangladesh. The study focused on students facing academic probation on two private universities in Bangladesh and analyzed students' response with respect to nine different factors - difficulty in understanding language, weak communication skills, weak educational background, ‘grading is too difficult’, involvement with other activities, wrong course selection, lack of seriousness in studies, family problem and personal problem. In the survey, the sample consisted of 242 probation students: 80 per cent were male and 20 per cent were female. In this research, results suggest that probation students are more likely to experience academic difficulties, are more prone to drop out and, yet, are more willing to receive institutional assistance (how to return to good academic standing) as compared to other regular students. The authors conclude by discussing policy implications of the findings and defining avenues for further research. One of the shortcomings of this study is the use of private university student samples only. Consequently, the generalization of our results may be limited. The authors developed and instituted a probationary student support initiatives program to both assist these students and understand how their background characteristics and perceptions of the learning environment impacted on their academic standing.
The Voices of Teaching Assistants (Are We Value for Money?)
Authors: Roffey-Barentsen Jodi
Published: August 2014

This research gave voice to teaching assistants, exploring their experiences and perceptions. A small-scale case study approach was adopted, which aimed to interpret and explain human actions and thought through descriptions, capturing first person accounts. Qualitative data was collected from two focus group interviews. Participants were employed by Primary, Secondary and Special Schools. The research found that the main entry route into the role of teaching assistant was that of parent-helper. Previous skills and experience were not drawn upon or utilised by the schools. Differences in job titles were not reflected by the roles performed by the participants. For teaching assistants to be considered to provide ‘value for money’ a different approach to their deployment is required. The message voiced by teaching assistants was that there needs to be a clear career and related pay structure, with relevant job descriptions, which takes experience and qualifications into account.
Quality of University Graduates and Human Resources Development in Nigeria
Authors: Uche Rachel D.
Published: August 2014

The quality of graduates from Nigerian universities is reported to be on the decline, especially in critical and valuable skills, to the extent that companies hardly recruit but rather adopt employment protection strategies because, to them, these graduates do not meet the demands of the industry. The study therefore sought to ascertain the factors influencing the quality of graduates, using final year undergraduates of the University of Calabar. The expo-post facto design was utilized, two hypothesis were generated and through simple random sampling techniques, 200 respondents were drawn. Data were collected using a structured questionnaire and the analysis was done using one-way ANOVA. Results indicated that selection criteria had significant influence on academic performance but a non-significant influence on students' conduct. The recommendation was that, for Nigeria to meet its millennium developmental goal, only competent, high quality candidates with the right ability, interest, aptitude and motivation should be selected for admission based purely on merit.
The impact of neogene grassland expansion and aridification on the isotopic composition of continental precipitation
Authors: Chamberlain C. P. , Winnick M. J. , Mix H. T. , Chamberlain S. D. , Maher K.
Published: August 2014

The late Cenozoic was a time of global cooling, increased aridity, and expansion of grasslands. In the last two decades numerous records of oxygen isotopes have been collected to assess plant ecological changes, understand terrestrial paleoclimate, and to determine the surface history of mountain belts. The δ18O values of these records, in general, increase from the mid‐Miocene to the Recent. We suggest that these records record an increase in aridity and expansion of grasslands in midlatitude continental regions. We use a nondimensional isotopic vapor transport model coupled with a soil water isotope model to evaluate the role of vapor recycling and transpiration by different plant functional types. This analysis shows that increased vapor recycling associated with grassland expansion along with biomechanistic changes in transpiration by grasses themselves conspires to lower the horizontal gradient in the δ18O of atmospheric vapor as an air mass moves into continental interiors. The resulting signal at a given inland site is an increase in δ18O of precipitation with the expansion of grasslands and increasing aridity, matching the general observed trend in terrestrial Cenozoic δ18O records. There are limits to the isotopic effect that are induced by vapor recycling, which we refer to here as a “hydrostat.” In the modern climate, this hydrostatic limit occurs at approximately the boundary between forest and grassland ecosystems.
Time‐lapse monitoring of velocity changes in Utah
Authors: Kanu Chinaemerem , Snieder Roel , Pankow Kristine
Published: August 2014

The Eastern part of the Basin and Range, extending to the Wasatch fault region, is an actively deforming region characterized by varieties of extensive features and prominent seismicity along the intermountain seismic belt. The present‐day deformation of the intermountain seismic belt and the eastern Basin and Range province motivates an interest in continuous monitoring of the region. In this study we monitor time‐lapse velocity changes within Utah and eastern Nevada using coda waves generated by repeatable explosions. This monitoring characterizes velocity changes within the region from June to September of 2007. We observe, both temporally and spatially, variable velocity changes within the monitored region, with a maximum path average velocity change of 0.2%. This suggests a significant change in the velocity within the region given the short monitoring duration. Correlation of the temporal variation of the average velocity change with strains derived from GPS‐detrended displacements suggests that the velocity change might be driven by the broad deformation within the monitored region.
Recent anthropogenic and climatic history of Nunatsiavut fjords (Labrador, Canada)
Authors: Richerol Thomas , Pienitz Reinhard , Rochon André
Published: August 2014

This study aimed at reconstructing past climatic and environmental conditions of a poorly known and documented subarctic region, the Nunatsiavut (northern Labrador). A multiproxy approach was chosen, using fossil dinoflagellate cysts, diatoms and pollen from sediment cores taken into three fjords (Nachvak 59°N, Saglek 58.5°N, and Anaktalak 56.5°N). It allowed estimating terrestrial and marine influences in each fjord and documenting the recent history of human activities of the southern fjords (Saglek and Anaktalak). Fossil pollen and dinoflagellate cyst assemblages allowed depicting the climate history of the region over the last ~200–300 years. In contrast to the general warming trend observed in the arctic and subarctic Canada since the beginning of the Industrial Era, the Nunatsiavut has experienced relative climate stability over this period. Fossil pollen data show a shift of the tree limit to the south illustrating the cooling of terrestrial conditions. Our reconstructions suggest that the Labrador region has remained climatically stable over the last ~150–300 years, with just a slight cooling trend of the reconstructed sea surface temperatures, only perceptible in Saglek and Anaktalak fjords.
Comparison of four methods for transionospheric scintillation evaluation
Authors: Strangeways Hal J. , Zernov Nikolay N. , Gherm Vadim E.
Published: August 2014

There are a variety of methods employed for determination of phase and amplitude scintillation on satellite signals which generally employ different models and theory. The paper shows that in spite of this, very similar results can be found in most circumstances for four different methods for a very wide range of physical input parameters for weak scintillation conditions. Further comparison between results for different methods can help to determine their modeling errors and hence can also lead to more accurate determinations using improved models.
Climate trends and variability of rain rate derived from long‐term measurements in Norway
Authors: Tjelta Terje , Mamen Jostein
Published: August 2014

Radio systems are affected by rainfall, and the attenuation increases significantly with rain rate and frequency. Above about 10 GHz rainfall must generally be considered for estimating expected link availability with sufficient attenuation margin included. Rain rate is a key factor, and depending on climate, it will dictate the possible path length and other factors such as antenna size, for the planned performance of a system that operates at higher frequencies than about 10 GHz. This paper presents results from an analysis of Norwegian tipping bucket rain gauge data from 1967 to 2013. It is found that the rain rate currently used by the Radiocommunication Sector of the International Telecommunication Union recommendation for attenuation prediction, R0.01—the rate exceeded for 0.01% of an average year—has actually increased in all parts of the country from where long‐term data exist. Moreover, the year to year variability is significant. The increase may well be seen as a consequence of climate change. Such a change may cause higher attenuation effects than expected when radio links are designed following “normal” dimensioning procedures.
CFD modeling of LPG vessels under fire exposure conditions
Authors: D'Aulisa Arianna , Tugnoli Alessandro , Cozzani Valerio , Landucci Gabriele , Birk Albrecht Michael
Published: August 2014

Fire exposure of tanks used for the storage and transportation of liquefied gases under pressure may cause complex heat‐ and mass‐transfer phenomena that may contribute to compromise the integrity of the vessels in accident scenarios. Heat transfer through vessel lading results in the heat‐up of the internal fluid and the increase of vessel internal pressure. However, local temperature gradients in the liquid phase cause liquid stratification phenomena that result in a more rapid vaporization and pressure build‐up in the liquid phase. These fundamental phenomena were analyzed by a computational fluid dynamic model. The model was specifically focused on the early steps of vessel heat‐up, when liquid stratification plays a relevant role in determining the vessel internal pressure. A two‐dimensional transient simulation was set up using ANSYS FLUENT in order to predict the evolution of the liquid and vapor phases during the tank heat up. The model was validated against large scale experimental data available for liquefied petroleum gas vessels exposed to hydrocarbon fires, and was applied to case studies derived from recent accidental events in order to assess the expected time of pressure build‐up in different fire scenarios. © 2014 American Institute of Chemical Engineers AIChE J 60: 4292–4305, 2014
Cake properties of nanocolloid evaluated by variable pressure filtration associated with reduction in cake surface area
Authors: Iritani Eiji , Katagiri Nobuyuki , Nakajima Ryota , Hwang Kuo‐Jen , Cheng Tung‐Wen
Published: August 2014

A potential method has been developed for evaluating simultaneously both the average specific resistance and average porosity of the filter cake formed in unstirred dead‐end ultrafiltration of nanocolloids such as bovine serum albumin solution and silica sol. The method consists of variable pressure filtration followed by constant pressure filtration. The relation between the average specific cake resistance and the pressure drop across the cake was determined from the evolution of the filtration rate with time in the course of the variable pressure filtration period, based on the compressible cake filtration model. The average porosity was evaluated from the significant flux decline caused by a sudden reduction in the cake surface area in the middle of the constant pressure filtration period. The pressure dependences of both the average specific cake resistance and average cake porosity were obtained from only two runs which differed from each other in the pressure profiles. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3869–3877, 2014
A novel fluorinated polymeric product for photoreversibly switchable hydrophobic surface
Authors: Zhou Yin‐Ning , Li Jin‐Jin , Zhang Qing , Luo Zheng‐Hong
Published: August 2014

A new chemical product, that is, photoreversibly switchable hydrophobic surface coating, was synthesized by atom transfer radical polymerization and graft‐from method based on molecular design. Focusing on the strategy of new product development from the chemical product engineering perspective, the product characterization, switching mechanism analysis, performance evaluation, and model interpretation were carried out to confirm the new product manufacture and to ensure the product application with a following aging test. The results show that the product enables surfaces to have reversibly switchable wettability and excellent stability after a month‐long test with eight irradiation cycles. Additionally, the wetting behavior of silicon surface can be tuned between hydrophilicity and hydrophobicity based on blank sample using the surface engineering technique (decorated with functional film and surface roughening). The product presented here can be utilized for constructing a hydrophobic surface with photo‐induced controllable wettability in moisture‐resistance, and it also offers a new technique for the manipulation of liquids in microfluidic devices. © 2014 American Institute of Chemical Engineers AIChE J 60: 4211–4221, 2014
Numerical simulation of rapid expansion of supercritical carbon dioxide
Authors: Liu Jiewei , Do‐Quang Minh , Amberg Gustav
Published: August 2014

Axisymmetric rapid expansion of supercritical carbon dioxide is investigated in this article. The extended generalized Bender equation of state is used to give a good description of the fluids over a wide range of pressure and temperature conditions. The locations of Mach disks are analyzed and compared with an experimental correlation for the case where there is no plate positioned in front of the nozzle exit. It is found that the disagreement between our numerical results and the experimental formula is very small when the pressure ratio is small, and increases as the pressure ratio increases. It is also found that with different equations of state, the predicted positions of Mach disks do not differ a lot, but the temperature profiles in the chamber differ a lot. The case where there is a plate positioned in front of the nozzle exit is also studied in this article. A universal similarity solution is obtained. © 2014 American Institute of Chemical Engineers AIChE J, 61: 317–332, 2015
Injury rates on new and old technology oil and gas rigs operated by the largest United States onshore drilling contractor
Authors: Blackley David J. , Retzer Kyla D. , Hubler Warren G. , Hill Ryan D. , Laney A. Scott
Published: August 2014

Background

Occupational fatality rates among oil and gas extraction industry and specifically among drilling contractor workers are high compared to the U.S. all‐industry average. There is scant literature focused on non‐fatal injuries among drilling contractors, some of which have introduced engineering controls to improve rig efficiency and reduce injury risk.

Methods

We compared injury rates on new and old technology rigs operated by the largest U.S. drilling contractor during 2003–2012, stratifying by job type and grouping outcomes by injury severity and body part affected.

Results

Six hundred seventy‐one injuries were recorded over 77.4 million person‐hours. The rate on new rigs was 66% of that on old rigs. Roughnecks had lower injury rates on new rigs, largely through reduced limb injury rates. New rigs had lower rates in each non‐fatal injury severity category.

Conclusions

For this company, new technology rigs appear to provide a safer environment for roughnecks. Future studies could include data from additional companies. Am. J. Ind. Med. 57:1188–1192, 2014. © 2014 Wiley Periodicals, Inc.
Reaktivität und Stabilität von Glucosinolaten und ihren Abbauprodukten in Lebensmitteln
Authors: Hanschen Franziska S. , Lamy Evelyn , Schreiner Monika , Rohn Sascha
Published: August 2014

Die Chemie von Glucosinolaten und ihre Reaktionen während der Lebensmittelverarbeitung sind sehr komplex. Aufgrund ihrer Instabilität entsteht eine ganze Reihe von Abbau‐ und Reaktionsprodukten, die häufig ebenfalls reaktiv sind. Obwohl der übermäßige Genuss von Kohlsorten lange Zeit mit nachteiligen, vor allem goitrogenen (kropfbildenden) Wirkungen in Verbindung gebracht wurde, weisen aktuelle Ergebnisse aus epidemiologischen Studien auch auf potenziell positive Gesundheitseffekte hin. Insbesondere Gemüse aus der Familie der Kreuzblütler (Brassicaceae) wie Broccoli, Rettich oder Kohl sind reich an diesen interessanten pflanzlichen Metaboliten. Informationen zur Bioaktivität von Glucosinolaten sind aber nur dann von Nutzen, wenn man weiß, welche Verbindungen bei der Verarbeitung gebildet und anschließend verzehrt werden. Dieser Aufsatz bietet eine umfassende und detaillierte Übersicht über die chemische Reaktivität verschiedener Glucosinolate und ihrer Abbauprodukte während der Lebensmittelzubereitung.
Multiple Stable Conformations Account for Reversible Concentration‐Dependent Oligomerization and Autoinhibition of a Metamorphic Metallopeptidase
Authors: López‐Pelegrín Mar , Cerdà‐Costa Núria , Cintas‐Pedrola Anna , Herranz‐Trillo Fátima , Bernadó Pau , Peinado Juan R. , Arolas Joan L. , Gomis‐Rüth F. Xavier
Published: August 2014

Molecular plasticity controls enzymatic activity: the native fold of a protein in a given environment is normally unique and at a global free‐energy minimum. Some proteins, however, spontaneously undergo substantial fold switching to reversibly transit between defined conformers, the “metamorphic” proteins. Here, we present a minimal metamorphic, selective, and specific caseinolytic metallopeptidase, selecase, which reversibly transits between several different states of defined three‐dimensional structure, which are associated with loss of enzymatic activity due to autoinhibition. The latter is triggered by sequestering the competent conformation in incompetent but structured dimers, tetramers, and octamers. This system, which is compatible with a discrete multifunnel energy landscape, affords a switch that provides a reversible mechanism of control of catalytic activity unique in nature.
Oxygenase‐Catalyzed Desymmetrization of N,N‐Dialkyl‐piperidine‐4‐carboxylic Acids
Authors: Rydzik Anna M. , Leung Ivanhoe K. H. , Kochan Grazyna T. , McDonough Michael A. , Claridge Timothy D. W. , Schofield Christopher J.
Published: August 2014

γ‐Butyrobetaine hydroxylase (BBOX) is a 2‐oxoglutarate dependent oxygenase that catalyzes the final hydroxylation step in the biosynthesis of carnitine. BBOX was shown to catalyze the oxidative desymmetrization of achiral N,N‐dialkyl piperidine‐4‐carboxylates to give products with two or three stereogenic centers.
Total Synthesis of Myceliothermophins C, D, and E
Authors: Nicolaou K. C. , Shi Lei , Lu Min , Pattanayak Manas R. , Shah Akshay A. , Ioannidou Heraklidia A. , Lamani Manjunath
Published: August 2014

The total synthesis of cytotoxic polyketides myceliothermophins E (1), C (2), and D (3) through a cascade‐based cyclization to form the trans‐fused decalin system is described. The convergent synthesis delivered all three natural products through late‐stage divergence and facilitated unambiguous C21 structural assignments for 2 and 3 through X‐ray crystallographic analysis, which revealed an interesting dimeric structure between its enantiomeric forms.
Direct Catalytic Olefination of Alcohols with Sulfones
Authors: Srimani Dipankar , Leitus Gregory , Ben‐David Yehoshoa , Milstein David
Published: August 2014

The synthesis of terminal, as well as internal, olefins was achieved by the one‐step olefination of alcohols with sulfones catalyzed by a ruthenium pincer complex. Furthermore, performing the reaction with dimethyl sulfone under mild hydrogen pressure provides a direct route for the replacement of alcohol hydroxy groups by methyl groups in one step.
The Total Synthesis of Isodon Diterpenes
Authors: Lazarski Kiel E. , Moritz Benjamin J. , Thomson Regan J.
Published: August 2014

Families of structurally related molecules often provide stimulating targets for organic chemists that are engaged in the development of new methods and strategies for natural product synthesis. While typically focused on specific molecules, these synthetic investigations often lead to generalizable concepts and significant opportunities for learning in a greater sense. Historically well‐investigated families of natural products, such as the prostanoids, indole alkaloids, and macrolide antibiotics, provide ample evidence for the enduring value of these collective activities. In this Minireview, we turn our attention to the polycyclic family of diterpenes isolated from the Isodon genus of plants and provide an account of the recent methods and strategies utilized for their total synthesis.
Synthesis and Reaction of the First 1,2‐Oxaphosphetane Complexes
Authors: Kyri Andreas Wolfgang , Nesterov Vitaly , Schnakenburg Gregor , Streubel Rainer
Published: August 2014

While PV 1,2‐oxaphosphetanes are well known from the Wittig reaction, their PIII analogues are still unexplored. Herein, the synthesis and reactions of the first 1,2‐oxaphosphetane complexes are presented, which were achieved by reaction of the phosphinidenoid complex [Li(12‐crown‐4)(solv)][(OC)5W{(Me3Si)2HCPCl}] with different epoxides. The title compounds appeared to be stable in toluene up to 100 °C, before unselective decomposition started. Acid‐induced ring expansion with benzonitrile resulted in selective formation of the first complex bearing a 1,3,4‐oxazaphosphacyclohex‐2‐ene ligand.
Cobalt‐Catalyzed Formal [4+2] Cycloaddition of α,α′‐Dichloro‐ortho‐Xylenes with Alkynes
Authors: Komeyama Kimihiro , Okamoto Yuji , Takaki Ken
Published: August 2014

A formal [4+2] cycloaddition of α,α′‐dichloro‐ortho‐xylenes with various alkynes has been developed using a low‐valent cobalt catalyst. The transformation has a wide substrate scope and high functional‐group tolerance and led to 1,4‐dihydronaphthalenes. The formed cycloadducts were easily aromatized with MnO2 under air. A mechanistic investigation suggests that the transformation proceeds through a benzyl cobaltation of alkyne, not the classical Diels–Alder reaction of ortho‐quinodimethanes. This methodology provides a straightforward and streamlined access to linearly expanded π‐conjugated aromatics.
Crystallization, melting behavior, and crystal structure of reactive, intumescent, flame‐retardant polypropylene
Authors: Li Guixun , Cao Shaokui , Zheng Shijun , Wang Wanjie , Cao Yanxia , Wang Jingwu
Published: August 2014

Polypropylene (PP)/2‐({9‐[(4,6‐diamino‐1,3,5‐triazin‐2‐yl) amino]‐3,9‐dioxido‐2,4,8,10‐tetraoxa‐3,9‐diphosphaspiro [5.5] undecan‐3‐yl} oxy) ethyl methacrylate (EADP) composites were prepared by the blending of PP with EADP as a new flame‐retardant material. The nonisothermal crystallization and melting behaviors of composites were investigated with differential scanning calorimetry (DSC). Their crystal morphologies and structures were studied by polarized optical microscopy (POM) and X‐ray diffraction (XRD), respectively. The DSC results show that the addition of EADP increased the crystallization onset temperature, crystallization peak temperature, and degree of crystallinity of PP in the PP/EADP composites. The melting onset temperature and melting end temperature of the PP/EADP composites decreased slightly, whereas the melting peak temperature of the PP/EADP composites increased. The POM results show that the addition of EADP greatly reduced the crystal size of PP in the composites. When the content of EADP in the PP/EADP composites was increased, the crystal size of PP became smaller. The XRD results indicate that the addition of EADP changed the crystal structure of PP in the PP/EADP composites, which exhibited both α‐form and β‐form crystal structures. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41374.