bluuebunny/crossref_metadata_2025 huggingface dataset:
Bentuk Sekuritisasi dan Kepentingan Nasional Indonesia terhadap Konflik Laut Tiongkok Selatan
Authors: Nauvalliado Muhammad Zahran
Published: April 2024

Indonesia adalah sebuah negara kepulauan yang mana berbatasan langsung dengan kawasan perairan internasional. Konflik-konflik serta persengketaan wilayah kedaulatan rawan terjadi atas klaim sepihak dari satu negara terhadap negara lain di sekitarnya. Artikel ini secara spesifik akan mengungkap bentuk sekuritisasi Indonesia terhadap konflik persengketaan kawasan Laut Tiongkok Selatan yang menggeret Indonesia masuk ke dalam permasalahan. Tiongkok secara sepihak mengklaim bahwa Laut Natuna Utara adalah bagian dari kebijakan Tiongkok mengenai sembilan garis putus-putus yang didasarkan kepada historis negara itu sendiri. Indonesia sudah sepantasnya dan wajib dalam penguatan kedaulatan teritorial kawasan perairan yang sudah ditentukan secara hukum internasional.
Dinamika Keamanan Manusia
Authors: Sausan Hana
Published: April 2024

Studi ini bertujuan untuk mendalami dimensi keamanan manusia dalam konteks krisis Rohingya, dengan mengaplikasikan metode penelitian kualitatif. Penelitian ini menggali sejarah, demografi, dan dinamika politik yang membentuk krisis kompleks di Myanmar dan dampaknya di tingkat regional. Pendekatan kualitatif melibatkan wawancara mendalam, analisis konten, dan pengamatan terhadap situasi lapangan untuk memahami dampak krisis secara holistik. Hasil penelitian menyoroti bahwa penolakan kewarganegaraan dan pelanggaran Hak Asasi Manusia (HAM) terhadap komunitas Rohingya telah menciptakan tantangan serius terkait keamanan manusia. Ketidakpastian status kewarganegaraan mengakibatkan ketidakstabilan sosial dan ekonomi, membatasi akses ke pendidikan dan layanan kesehatan, serta meningkatkan risiko konflik internal. Penggunaan metode kualitatif memungkinkan pemahaman yang mendalam tentang dampak psikologis dan sosial pada masyarakat Rohingya, serta menyoroti aspirasi dan harapan mereka terkait keamanan dan keadilan. Penelitian ini merumuskan rekomendasi kebijakan yang didasarkan pada temuan kualitatif, menekankan perlunya respons internasional yang lebih terkoordinasi, perlindungan HAM yang lebih kuat, dan upaya pembangunan yang berkelanjutan untuk mengatasi krisis ini. Pendekatan kualitatif membuka ruang untuk pemahaman yang lebih mendalam terhadap kompleksitas krisis Rohingya, memungkinkan implementasi kebijakan yang lebih efektif dan berkelanjutan.
Grade Point Average: The Relationship with Results of Entrance Assessment, Learning Motivation, Achievement Motivation, and Perception of Teacher Leadership
Authors: Sereda Nataliia , Reznik Svitlana , Solodovnyk Tetiana , Bogdan Zhanna , Romanovskyі Oleksandr
Published: April 2024

The purpose of this study is to determine the relationship between the Grade Point Average (GPA) of graduates of social majors of National Technical University «Kharkiv Polytechnic Institute» (Ukraine) with results of the entrance assessment, learning motivation (educational and cognitive, professional motives and motives for creative self-realization), achievement motivation, perception of teacher leadership. The research was conducted during 2018-2020, calculations were made for a total of 502 respondents with using the correlation and regression analysis. Results of the study demonstrate a significant correlation between the level of academic success and the level of educational and cognitive motivation of graduates (r=0,644, р<0,01). A less strong connection was found between GPA of graduates and results of the entrance examination (r= 0,502, р<0,01). The weakest, albeit statistically significant, relationship is between GPA variables and students’ perception of teacher leadership (r=0.160, p<0.01), as well as between GPA and motives for creative self-realization (r=0,139, р<0,01). The article also carried out a correlation analysis for groups of students by level of education, form of study, majors and gender of respondents. Obtained results are discussed from the point of view of improving the procedure for selecting applicants for admission to the University and improving the educational process.
Efficiency Assessment on Codified Knowledge Products: An SFA Approach
Authors: Ferro Gustavo , Gatti Nicolás
Published: April 2024

Knowledge applied to innovation is increasingly recognized as an explanatory factor of economic growth. Innovation derives from applying knowledge to generate new products or processes. National Innovation Systems (NIS) performs as the formal or informal network of people within institutions, interacting to produce and apply knowledge to innovation. NIS can be understood as two subsystems: one based on scientifical and technological work, producing codified products (publications and patents), and the other centered on practical actions to diffuse, apply, and use knowledge. Our objective is to assess cost efficiency in the production of codified knowledge outputs (CKO), being our unit of analysis NIS (countries). To attain our goal, we apply a Stochastic Frontier Analysis (SFA) to estimate a cost frontier of CKO. The sample is a panel that includes 1189 observations, for 23 years (1996-2019), and 82 countries. Our main results identify determinants and patterns of efficiency and productivity, tendencies, and specifics of countries and groups of them.
Tax and customs status of imported fish products manufactured in the Exclusive Economic Zone of Russia and the World Ocean
Authors: Sidorova Elena Yur'nevna , Artem'ev Aleksei Aleksandrovich
Published: April 2024

Subject – customs status of goods. The aim is to study the tax and customs status of fish import and of fish products made in the exclusive economic zone of the Russian Federation (hereinafter referred to as the EEZ of the Russian Federation) and the World Ocean. The authors of the study analyze the law enforcement practice, formed over the past few years, what allow them to draw attention to the methodological underdevelopment of a set of issues related to the determination of customs legal relations of fish and fish products imported (manufactured) by Russian fishing vessels (or production of fish products) (hereinafter - Goods) outside the state territory of Russia. Scientific contribution: Development of practical cases to determine the tax and customs consequences of importing fish (catches), produced (caught) in the EEZ of the Russian Federation. Results and conclusions: The results of the study show that the current regulation (norms of the Customs Code of the EAEU) does not allow to make an unambiguous conclusion as to whether such goods should be considered in customs legal relations as "goods of the Union" or as "foreign goods". In connection with the above, it seems relevant to solve the problem related to the development of methodological approaches to determining the status of imported Goods.
Seasonal fluctuations of litter and soil Collembola and their drivers in rainforest and plantation systems
Authors: Susanti Winda Ika , Krashevska Valentyna , Widyastuti Rahayu , Stiegler Christian , Gunawan Dodo , Scheu Stefan , Potapov Anton M.
Published: April 2024

Rainforest conversion and expansion of plantations in tropical regions change local microclimate and are associated with biodiversity decline. Tropical soils are a hotspot of animal biodiversity and may sensitively respond to microclimate changes, but these responses remain unexplored. To address this knowledge gap, here we investigated seasonal fluctuations in density and community composition of Collembola, a dominant group of soil invertebrates, in rainforest, and in rubber and oil palm plantations in Jambi province (Sumatra, Indonesia). Across land-use systems, the density of Collembola in the litter was at a maximum at the beginning of the wet season, whereas in soil it generally varied little. The community composition of Collembola changed with season and the differences between land-use systems were most pronounced at the beginning of the dry season. Water content, pH, fungal and bacterial biomarkers, C/N ratio and root biomass were identified as factors related to seasonal variations in species composition of Collembola across different land-use systems. We conclude that (1) conversion of rainforest into plantation systems aggravates detrimental effects of low moisture during the dry season on soil invertebrate communities; (2) Collembola communities are driven by common environmental factors across land-use systems, with water content, pH and food availability being most important; (3) Collembola in litter are more sensitive to climatic variations than those in soil. Overall, the results document the sensitivity of tropical soil invertebrate communities to seasonal climatic variations, which intensifies the effects of the conversion of rainforest into plantation systems on soil biodiversity.
Health and ecological risk of heavy metals in agricultural soils related to Tungsten mining in Southern Jiangxi Province, China
Authors: Lai Jinhu , Ni Yan , Xu Jinying , Wu Daishe
Published: April 2024

Background

Dayu County, a major tungsten producer in China, experiences severe heavy metal pollution. This study evaluated the pollution status, the accumulation characteristics in paddy rice, and the potential ecological risks of heavy metals in agricutural soils near tungsten mining areas of Dayu County. Furthermore, the impacts of soil properties on the accumulation of heavy metals in soil were explored.

Methods

The geo-accumulation index (Igeo), the contamination factor (CF), and the pollution load index (PLI) were used to evaluate the pollution status of metals (As, Cd, Cu, Cr, Pb, Mo, W, and Zn) in soils. The ecological risk factor (RI) was used to assess the potential ecological risks of heavy metals in soil. The health risks and accumulation of heavy metals in paddy rice were evaluated using the health risk index and the translocation factor (TF), respectively. Pearson’s correlation coefficient was used to discuss the influence of soil factors on heavy metal contents in soil.

Results

The concentrations of metals exceeded the respective average background values for soils (As: 10.4, Cd: 0.10, Cu: 20.8, Cr: 48.0, Pb: 32.1, Mo: 0.30, W: 4.93, Zn: 69.0, mg/kg). The levels of As, Cd, Mo, and tungsten(W) exceeded the risk screening values for Chinese agricultural soil contamination and the Dutch standard. The mean concentrations of the eight tested heavy metals followed the order FJ-S > QL > FJ-N > HL > CJ-E > CJ-W, with a significant distribution throughout the Zhangjiang River basin. Heavy metals, especially Cd, were enriched in paddy rice. The Igeo and CF assessment indicated that the soil was moderately to heavily polluted by Mo, W and Cd, and the PLI assessment indicated the the sites of FJ-S and QL were extremely severely polluted due to the contribution of Cd, Mo and W. The RI results indicated that Cd posed the highest risk near tungsten mining areas. The non-carcinogenic and total carcinogenic risks were above the threshold values (non-carcinogenic risk by HQ > 1, carcinogenic risks by CR > 1 × 10−4 a−1) for As and Cd. Correlation analysis indicated that K2O, Na2O, and CaO are main factors affecting the accumulation and migration of heavy metals in soils and plants. Our findings reveal significant contamination of soils and crops with heavy metals, especially Cd, Mo, and W, near mining areas, highlighting serious health risks. This emphasizes the need for immediate remedial actions and the implementation of stringent environmental policies to safeguard health and the environment.
Motivation Level of ODL Students Based on Keller’s ARCS Model: A Case of Dual Mode University in West Bengal, India
Authors: Dey Binayak , Panda Bhujendra Nath
Published: April 2024

Aims: This research seeks to explore higher education students’ motivation level under the ODL mode of study and compare the motivation level with respect to gender based on Keller’s ARCS model.

Place and Duration of Study: The study was conducted among the higher education students who enrolled in different ODL programs under the dual-mode University in West Bengal. Survey was administered for two weeks during Personal Contact Programme (PCP) for the academic session of 2023-2024.

Methodology: The present research used a quantitative research method. We used the IMMS questionnaire based on the Kellers ARCS model. There are 36 items and 4 dimensions in the IMMS. On the standardized Cronbach Alpha, the overall reliability of all the scales was 0.92. The level of motivation was then assessed using some basic statistics.

Results: The minimum and maximum overall motivation levels among the 77 ODL students were 2.83 and 4.97, respectively. The overall motivation levels mean score was 4.32, meaning it is very positive. Depending on independent t-test result, no significant difference was found in motivation levels among ODL students related to gender. ARCS model indicates that the motivation level of students under ODL mode of study is in a high category range (4.00-5.00) with an average value of 4.32.

Conclusion: The success and effectiveness of the ODL system largely depends on self-learning materials. The learning material in open and distance learning should promote autonomy, motivation, and self-regulated learning while fostering a sense of community and belonging despite physical separation. It is recommended that the ODL professionals should offer more engaging teaching-learning environment that increases ODL students’ competence, giving ODL students more opportunities to learn independently, and involve them in planning learning activities that might enhance their motivation level.
Acrocentric cryptic translocation associated with nondisjunction of chromosome 21
Authors: Ramos Sandra , Alcántara Miguel Angel , Molina Bertha , del Castillo Victoria , Sánchez Silvia , Frias Sara
Published: December 2007

Down syndrome is the most frequent autosome aneuploidy in live newborns. It was recently proposed that pericentromeric cryptic translocations might be a cause of chromosome nondisjunction. We describe here a phenotypically normal subject with a cryptic translocation involving the short arms of chromosomes 13 or 21 and 22, who had a son with Down syndrome. Fluorescent in situ hybridization (FISH) on paternal metaphase chromosomes showed a chromosome 22 centromere positive for both 13/21 and 14/22 centromeric probes. The same probes hybridized on different and contiguous sites of chromatin fibers, eliminating cross‐hybridization artifacts. This confirmed the presence of a cryptic translocation generating a dicentric chromosome 22: fib ish dic(21;22)(21pter → 21q10::22q10 → 22qter)(D13/21Z1+;D14/22Z1+). Microsatellite STR segregation analysis confirmed the paternal origin of the additional chromosome 21 in the Down syndrome patient. To determine whether the father showed a higher‐than‐normal frequency of chromosome 21 nondisjunction, FISH analysis of spermatozoa was performed using a sequence specific probe (21q22.13–q22.2). The frequency of disomy 21 spermatozoa was twofold higher in the cryptic translocation carrier as compared to normal subjects (P < 0.014), suggesting that the rearrangement favored the nondisjunction of chromosome 21. This is the first report associating a pericentromeric cryptic translocation of acrocentric chromosomes with the generation of aneuploidy, supporting the hypothesis that this type of rearrangement may contribute to abnormal chromosomal segregation. © 2007 Wiley‐Liss, Inc.
Synthesis and characterization of a novel proton‐exchange membrane for fuel cells operating at high temperatures and low humidities
Authors: Chuang Ching‐Nan , Chao Liang , Huang Ying‐Jie , Hsieh Tar‐Hwa , Chuang Hung‐Yi , Lin Shu‐Chi , Ho Ko‐Shan
Published: December 2007

The synthesis of a p‐toluidine/formaldehyde (PTF) resin was performed, and the effects of the molar ratio of the individual monomers and the polymerization conditions on the structure of the PTF resin were studied. Fourier transform infrared and 13C‐NMR spectra were used to characterize the PTF. Wide‐angle X‐ray diffraction patterns revealed the crystalline structures of various PTFs. Polarized optical microscopy revealed that the molar ratio of the monomers had a strong effect on the crystalline morphologies. A longer polymerization time turned out a polymer with a higher intrinsic viscosity and molecular weight, which led to differences in the proton conductivity. All of the PTFs showed a higher proton conductivity than a commercial Nafion membrane at 90–100°C and 0% relative humidity. The proton conductivity of the PTF series could be improved by sulfonation with sulfuric acid and could be maintained after blending with polyurethane. Pure methanol could be used as a fuel source because of the insolubility and nonwetting properties of PTF in methanol to increase the output current density for a PTF membrane electrode assembly. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008
Developmental expression of LC3α and β: Absence of fibronectin or autophagy phenotype in LC3β knockout mice
Authors: Cann Gordon M. , Guignabert Christophe , Ying Lihua , Deshpande Niru , Bekker Janine M. , Wang Lingli , Zhou Bin , Rabinovitch Marlene
Published: December 2007

Murine light chain 3 (LC3) exists as two isoforms, LC3α and β: LC3β is an RNA‐binding protein that enhances fibronectin (FN) mRNA translation, and is also a marker of autophagy. We report embryonic expression patterns for LC3α and LC3β, with some overlap but notable differences in the brain, and in tissues of non‐neuronal origin. LC3β knockout (−/−) mice develop normally without a compensatory increase in LC3α. LC3β−/− embryonic fibroblasts (MEFs) exhibit reduced FN synthesis but maintain wild type (WT) levels of FN protein. No significant changes in proteins associated with FN turnover, i.e., caveolin‐1, LRP‐1, or matrix metalloproteinases were identified. Autophagosomes form in amino acid–starved LC3β−/−MEFs, and Caesarean‐delivered pups survive as long as WT pups without an increase in LC3‐related proteins linked to autophagy. These results suggest novel compensatory mechanisms for loss of LC3β, ensuring proper FN accumulation and autophagy during fetal and neonatal life. Developmental Dynamics 237:187–195, 2008. © 2007 Wiley‐Liss, Inc.
Synthesis of a Naturally Occurring Diene‐Containing Amino Acid and Its Glutamyl Dipeptide via N‐Acyliminium Ion Chemistry
Authors: Berkheij Martin , Dijkink Jan , David Olivier R. P. , Sonke Theo , IJzendoorn Denis R. , Blaauw Richard H. , van Maarseveen Jan H. , Schoemaker Hans E. , Hiemstra Henk
Published: December 2007

The syntheses of the naturally occurring unusual unsaturated amino acid (S)‐2‐amino‐3‐methylene‐4‐pentenoic acid and the corresponding γ‐glutamyl dipeptide are described. Key steps are an N‐acyliminium ion addition using allenylmethylsilane as nucleophile and an enzymatic resolution mediated by the L‐aminopeptidase from Pseudomonas putida. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Encapsulation and release of a fluorescent probe, khusimyl dansylate, obtained from vetiver oil by complex coacervation
Authors: Prata A. S. , Menut C. , Leydet A. , Trigo J. R. , Grosso C. R. F.
Published: December 2007

The essential oil of vetiver [Vetiveria zizanoides (L.) Nash ex. Small] is widely used in the perfume industry, owing to its pleasant, long‐lasting, woody aroma. If this substance can be encapsulated in microparticles so that its release can be controlled, the effective duration of its properties should be extended for a much longer period of time. The present study was thus designed to investigate the encapsulation of this vetiver essential oil in microparticles. Since the detection of the effective release of such a complex mixture from these microparticles into the receiving medium can be problematic, an identifiable probe can be released with it to facilitate evaluation of the progression of the release process. Zizanoic acid is one of the compounds found in vetiver oil which depreciates its sensorial quality. This acid was thus extracted and reduced to the corresponding alcohol, khusimol, which was combined with dansyl chloride to form a fluorescent ester, khusimyl dansylate (KD). The vetiver oil and the fluorescent probe were then encapsulated (100:1) in microparticles produced by the complex coacervation of gum Arabic and gelatin. The microparticles showed spherical shape, multinuclear distribution of the core material and high encapsulation efficiency (95%). Two versions of these microparticles, moist and freeze‐dried ones, were tested for the release of the KD into an ethanol medium. The moist particles released the whole KD after 5 h, although only 80% of the fluorescent probe was released with the freeze‐dried microparticles at that time, probably due to the constriction caused by freeze‐drying. The release of the components of vetiver oil, under the same experimental conditions, was followed, in parallel, by gas chromatography and the results obtained were compared and discussed. Copyright © 2007 John Wiley & Sons, Ltd.
On the relation between order of accuracy, convergence rate and spectral slope for linear numerical methods applied to multiscale problems
Authors: Holdaway D. , Thuburn J. , Wood N.
Published: December 2007

The relation between order of accuracy and convergence rate for simple linear finite difference schemes for differentiation and advection is examined theoretically and empirically. For sufficiently smooth functions, i.e. those with sufficiently steep spectral slope, the convergence rate is given by the order of accuracy. For less smooth functions, with shallower spectral slope, differentiation and advection behave slightly differently: the convergence rate of a finite difference derivative is determined entirely by the spectral slope, while the convergence rate of a finite difference advection scheme is determined by an interaction between the spectral slope and the order of accuracy. © Crown copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Parallel non‐iterative methods for evolutionary semilinear flow problems
Authors: Arrarás A. , Portero L. , Jorge J. C.
Published: December 2007

This paper deals with the efficient numerical solution of semilinear parabolic problems that describe flow phenomena through non‐isotropic porous media. For the time integration of such problems, we propose a linearly implicit fractional step method that considers function and operator splittings related to suitable decompositions of the flow domain. The resulting family of elliptic problems is discretized in space by means of the support‐operator technique, obtaining a nine‐cell finite difference scheme on a logically rectangular grid. Owing to the chosen splittings, the totally discrete scheme involves sets of uncoupled linear systems that can be solved in parallel. Finally, a numerical experiment is included in order to show the unconditionally convergent behaviour of the scheme. Copyright © 2007 John Wiley & Sons, Ltd.
High‐resolution finite volume computations using a novel weighted least‐squares formulation
Authors: Mandal J. C. , Rao S. , Subramanian J.
Published: December 2007

High‐resolution finite volume schemes based on a novel reconstruction technique, SDWLS (solution‐dependent weighted least squares) are considered. The SDWLS technique, originally developed for second‐order variable reconstruction by Mandal and Subramanian (Appl. Numer. Math., 2007; DOI: 10.1016/j.apnum.2007.02.003), is further extended to third‐order reconstruction with compact stencils involving only the nearest neighbors. The new schemes are applied to solve a few numerical test examples, involving scalar conservation laws and the system of non‐linear gas dynamics equations, in order to study their performance. Significant improvements in solution accuracy have been achieved with the second‐ and third‐order SDWLS reconstruction techniques. Copyright © 2007 John Wiley & Sons, Ltd.
Elimination of organic matter present in wastewaters from the cork industry by membrane filtration
Authors: Benítez F Javier , Leal Ana I , Real Francisco J , Acero Juan L , Roldán Gloria
Published: December 2007

BACKGROUND: The first stage of the cork industrial process generates great volumes of wastewater with moderate to high organic pollutant content that must be purified using different procedures, such as filtration by membranes.

RESULTS: The tangential filtration of these wastewaters was studied using two different laboratory equipments. In the first one, three ultrafiltration (UF) membranes were tested, with molecular weight cut‐off (MWCO) 100 kDa and 30 kDa, and two operating modes were used: total recycling of permeate and retentate streams, and in continuous mode, without recycling both streams. In the total recycling UF experiments, the influence of the operating variables on the permeate flux was first established. The effectiveness of the different membranes was determined by evaluating the rejection coefficients for several parameters that measure the global pollutant content of the effluent. The values found for these rejection coefficients were in the following order: ellagic acid and color > absorbance at 254 nm > tannic content > COD (chemical oxygen demand). In the continuous mode experiments, the fouling mechanism for each membrane was established by fitting the experimental data to various filtration fouling models given in the literature. The operating mode in the second equipment was batch concentration, and additional experiments were carried out with an UF membrane (2 kDa), and with a NF membrane (with MWCO in the range 150–300 Da).

CONCLUSIONS: The three operating modes tested provided different rejection levels of organic matter; among them, the most effective procedure tested was batch concentration mode using a NF membrane. Copyright © 2007 Society of Chemical Industry
Thermogravimetric characteristics of aerobic granules developed at different salinities
Authors: Li Zhihua , Wang Xiaochang
Published: December 2007

BACKGROUND: Aerobic granular sludge is a self‐immobilization biotechnology for wastewater treatment. The thermogravimetric characteristics of aerobic granules were investigated in this study.

RESULTS: The strongly physically bound water in granules that developed at a salinity of 1% (in reactor R1) and 5% (in reactor R2) were 5% and 3%, respectively. In addition, the extracellular polymer substances (EPS) affected the bound water more significantly at a low salinity than a higher one. Based on thermogravimetric analysis (TGA), granules that developed at low salinity (such as 1% in R1) exhibited a rich diversity of organic components, and higher total EPS concentrations, inferred from the ratios of volatile solids to total solids. Additionally, the maximum weight loss rates of the granules in all reactors occurred at a temperature of around 250 °C and the endothermic peaks shifted to a relatively low temperature with increasing salinity regardless of the existence of EPS.

CONCLUSION: Increasing the salinity in the substrates slightly decreased the bound water fraction in granules and reduced the richness of the granule components as well as the biodiversity. This study provides detailed information on the components of aerobic granule. Copyright © 2007 Society of Chemical Industry
Kinetic Studies of Polyethylene Terephthalate Synthesis with Titanium‐Based Catalyst
Authors: Ahmadnian Fatemeh , Reichert Karl‐Heinz
Published: December 2007

Summary: Thermogravimetric analysis and stirred tank reactor techiques were used to study the kinetic of polycondensation of bis‐hydroxy ethylene terephthalate catalyzed by titanium tetrabutylate. Polycondensation reaction can be modelled best with a second order reaction with respect to hydroxyl end groups concentration. Titanium tetrabutylate is a precursor and needs preactivation for polycondensation catalysis. Kinetic data depends on the mode of operation in thermogravimetric analysis. In nonisothermal mode, the overall activation energy was determined by model‐free method and the pre‐exponential factor was found to be affected by catalyst concentration. The kinetic study of isothermal reaction in thermogravimetric analysis is complex due to lack of a precise way to reach desired isothermal temperature and high activity of the catalyst. Titanium catalyst shows higher activity and lower selectivity than antimony catalyst but its activity is affected by the nature of ligands.
Comparing Methods for Calculating the Heat Flow Rate of Reactions in Different Bench‐Scale Calorimeters
Authors: Gaulke Arnd‐Lüder , Pauer Werner , Moritz Hans‐Ulrich
Published: December 2007

Summary: A transfer function of the RC1e™ (Mettler‐Toledo) calorimeter was obtained by calibration with a heating cartridge. With this function it was possible to determine the heat flow rate and total heat of different polymerization reactions. The calorimeter operates in isothermal as well as in isoperibolic mode. Additionally, 1‐vinyl‐2‐pyrrolidone and acrylic acid were polymerized in a three‐neck flask. In this common laboratory device the heat flow rate was obtained by using a transfer function calculated by calibration with a heating cartridge. Thus, the heat of polymerization can be obtained without using a calorimeter and without solving the heat balance equation.
Block copolymer preparation by atom transfer radical polymerization under emulsion conditions using a nanoprecipitation technique
Authors: Chan‐Seng Delphine , Rider David A. , Guérin Gérald , Georges Michael K.
Published: December 2007

Living‐radical polymerization of acrylates were performed under emulsion atom transfer radical polymerization (ATRP) conditions using latexes prepared by a nanoprecipitation technique previously employed and optimized for the polymerization of styrene. A macroinitiator of poly(n‐butyl acrylate) prepared under bulk ATRP was dissolved in acetone and precipitated in an aqueous solution of Brij 98 to preform latex particles, which were then swollen with monomer and heated. Various monomers (i.e. n‐butyl acrylate, styrene, and tert‐butyl acrylate) were used to swell the particles to prepare homo‐ and block copolymers from the poly(n‐butyl acrylate) macroinitiator. Under these conditions latexes with a relatively good colloidal stability were obtained. Furthermore, amphiphilic block copolymers were prepared by hydrolysis of the tert‐butyl groups and the resulting block copolymers were characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The bulk morphologies of the polystyrene‐b‐poly(n‐butyl acrylate) and poly(n‐butyl acrylate)‐b‐poly(acrylic acid) copolymers were investigated by atomic force microscopy (AFM) and small angle X‐ray scattering (SAXS). © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 625–635, 2008
Preparation of ε‐HNIW by a One‐Pot Method in Concentrated Nitric Acid from Tetraacetyldiformylhexaazaisowurtzitane
Authors: Jin Shaohua , Shu Qinghai , Chen Shusen , Shi Yanshan
Published: December 2007

ε‐HNIW was prepared by a one‐pot method in concentrated nitric acid from tetraacetyldiformylhexaazaisowurtzitane (TADFIW). γ‐HNIW was firstly obtained, then γ‐HNIW was directly transformed to ε‐HNIW in the solution in which nitration reaction occurred. The acid number of ε‐HNIW prepared by the method mentioned above is less than 0.2‰, yield of ε‐HNIW is up to 91%, and the purity of ε‐HNIW is up to 99.5%. Because steps of filtration and drying of γ‐HNIW were omitted, the process by which ε‐HNIW was prepared simplified greatly.
Detonation Measurements on Damaged LX‐04
Authors: Hsu Peter , Souers P. Clark , Chidester Steve , Alvarez John , De Haven Martin , Garza Raul , Harwood Pat , Maienschein Jon
Published: December 2007

We have applied thermal insults on LX‐04 at 185 °C and found that the material expanded significantly, resulting in a bulk density reduction of 12%. Subsequent detonation experiments (three cylinder tests) were conducted on the thermally damaged LX‐04 samples and pristine low‐density LX‐04 samples and the results showed that the fractions reacted were close to 1.0. The thermally damaged LX‐04 and pristine low‐density LX‐04 showed detonation velocities of 7.7–7.8 mm μs−1, significantly lower than that (8.5 mm μs−1) of pristine high‐density LX‐04. Detonation energy densities for the damaged LX‐04, low‐density pristine LX‐04, and hot cylinder shot of LX‐04 were 6.48, 6.62, and 6.58 kJ cm−3, respectively, lower than the detonation energy density of 8.11 kJ cm−3 for the high density pristine LX‐04. The break‐out curves for the detonation fronts showed that the damaged LX‐04 had longer edge lags than the high density pristine LX‐04, indicating that the damaged explosive is less ideal.
Evidence for a High‐Pressure Phase Transition of ε‐2,4,6,8,10,12‐Hexanitrohexaazaisowurtzitane (CL‐20) Using Vibrational Spectroscopy
Authors: Ciezak Jennifer A. , Jenkins Timothy A. , Liu Zhenxian
Published: December 2007

The high‐pressure response of ε‐2,4,6,8,10,12‐hexanitrohexaazaisowurtizane (CL‐20) has been examined to 27 GPa in diamond anvil cells using vibrational spectroscopy. The results reveal evidence of an ε→γ pressure‐induced phase transition between 4.1 and 6.4 GPa and suggest the existence of a γ→ζ transition near 18.7 GPa. Several Raman and infrared frequencies were found to decrease in intensity as the phase boundaries are approached. An anomalous intensity increase was noted in the CNC infrared mode that is believed to result from an increase in the Raman cross‐section due to a stronger interlayer coupling under pressure.
Comparative ecology of Ostracoda (Crustacea) in two rheocrene springs (Bolu, Turkey)
Authors: Karakaş Sarı Pınar , Külköylüoğlu Okan
Published: December 2007

A total of ten taxa belonging to the class Ostracoda of the Crustacea (Darwinula stevensoni, Candona neglecta, Cypria ophthalmica, Ilyocypris bradyi, Prionocypris zenkeri, Herpetocypris chevreuxi, Psychrodromus olivaceus, Heterocypris incongruens, Scottia pseudobrowniana, Eucypris sp.) were collected from two rheocrene Darwinula stevensoni springs (Çetin Bey and Çaygökpınar springs) on 15 separate occasions between November 2002 and November 2004. Almost all of the species identified exhibit cosmopolitan distributions – at least in the Holarctic region. The presence of Scottia pseudobrowniana represents the second recording of this species in the ostracod fauna of Turkey. The dominant taxa in both springs was Cy. ophthalmica, I. bradyi, Pr. zenkeri and Ca. neglecta. Correlation analyses suggested a significant positive relationship in relative abundance between I. bradyi, Pr. zenkeri and Cy. ophthalmica. Species composition differed significantly between the upper and lower study sites for each spring, but differences could not be detected between sites at the same elevation across sites. Environmental tolerance index (ETI) values suggest that species with high optima and tolerance ranges show cosmopolitan characteristics.
Food supply problem in Leyte, Philippines, during the Japanese Occupation (1942–44)
Authors: Ara Satoshi
Published: December 2007

This article analyses the problem of food supply in Leyte, Philippines, during the Japanese occupation, which has not been studied in depth so far. It focuses on the interaction that took place among the Japanese occupying forces, anti-Japanese guerrilla groups, the Filipino collaborators, and the local residents over the procurement of foodstuffs. It also aims at clarifying the factors contributing to the disruption of the policy formulated by the Japanese and the Filipinos on the island. It is apparent in this study that the political and social characteristics in the province as well as the agricultural depression inherited from the American colonisation period brought about an outcome, which was different from the policy implemented in Manila.
Sexual dimorphism in Patagonotothen sima (Richardson, 1844)
Authors: Gosztonyi A.E. , Lopez-Arbarello A.
Published: December 2007

In Argentina, the Nototheniidae is represented by about 20 species, which mostly live in coastal waters of the continental shelf and slope. A few species inhabit inshore waters along the coasts of Patagonia and the Fueguian and Falkland (Malvinas) archipelagos and even reach rocky intertidal zones (Norman 1937, Hart 1946). Patagonotothen sima (Richardson 1844) is distributed in the Atlantic from the San Matías Gulf (around 42°S) to the Beagle Channel (54°50'S), inhabiting shallow waters including the intertidal zones. During faunal surveys in the rocky intertidal zone in Puerto Deseado, Santa Cruz (by A. Gosztonyi), it was noted that males of P. sima, one of the most common fish species in that habitat, appeared to have a higher second dorsal fin than the females.
Antarctic place-names
Authors: Hattersley-Smith G.
Published: December 2007

Throughout history ‘explorers’ from advanced countries have named place they have ‘discovered’ in lands occupied by native people from time immemorial, with the result that many local place-names have been disregarded and their history forgotten. Antarctica, however, is the one great land region on Earth that was truly ‘discovered’ when the South Shetland Islands were sighted in 1819, so that the place-names that gradually evolved in later exploration enshrine all the history of human endeavour on the continent.
Estimation of neutral lipid levels in Antarctic sea ice microalgae by nile red fluorescence
Authors: Priscu John C. , Priscu Linda R. , Palmisano Anna C. , Sullivan Cornelius W.
Published: December 2007

The fluorescent neutral lipid stain, nile red, was used to examine cell-specific neutral lipid levels in natural assemblages of Antarctic sea ice microalgae. Neutral lipid:chlorophyll, neutral lipid:particulate carbon (PC) and neutral lipid:particulate nitrogen (PN) ratios were highest in communities dominated by Nitzschia spp. and Navicula glaciei van Heurck. The lowest specific neutral lipid content was estimated in the congelation ice samples dominated by the diatom Amphiprora spp., and in surface assemblages dominated by Phaeocystis pouchetii Hariot and the dinoflagellate Gymnodinium sp. Scatter plots of neutral lipid on PC and PN, which included data from all assemblages, showed that assemblages dominated by P. pouchetii and Amphiprora spp. clustered near the origin reflecting their relatively lower specific neutral lipid levels, compared with assemblages dominated by N. glaciei and Nitzschia spp. Cellular PC:PN was significantly (P<0.001) lower in microalgae inhabiting surface melt pools or tide cracks compared to those associated with congelation or platelet ice.
First Polychelidae (Crustacea, Palinura) from the Jurassic of Antarctica
Authors: Aguirre-Urreta M.B. , Buatois L.A. , Chernoglasov G.Ch.B. , Medina F.A.
Published: December 2007

A new fossil genus of decapod Crustacea, belonging to the family Polychelidae is described from James Ross Island, Antarctic Peninsula. The specimen was obtained from a block of reworked Jurassic tuffaceous black shale belonging to the Ameghino (= Nordenskjöld) Formation in the Lower Cretaceous Kotick Point Formation. This is the first report of fossil Polychelidae in the Southern Hemisphere.
Population dynamics of Sterechinus antarcticus (Echinodermata: Echinoidea) on the Weddell Sea shelf and slope, Antarctica
Authors: Brey Thomas
Published: December 2007

Sterechinus antarcticus inhabits the shelf and the slope of the Weddell Sea and is the predominant echinoid between 450 and 1200 m. Growth lines visible in the half pyramids of the Aristotle's lantern were interpreted as annual growth marks. A Von Bertalanffy growth function was fitted to age-diameter data of 217 specimens (D∞ = 82.4 mm, K = 0.017 y−1, t0 = 1.633 y). Based on 92 trawl samples, a representative size-frequency distriution of S. antarcticus was established. From the growth curve, the size-frequency sample and diameter - weight regressions, mortality and somatic productivity of S. antarcticus were calculated by a size-converted catch curve and the weight specific growth rate method. Gonadal productivity was estimated by an average value for reproductive output of cold water echinoderms. Mortality rate Z as'well as somatic P/B ratio amounted to 0.07 y−1. Annual somatic production was estimated as 0.3 mg m−2y−1, and annual gonadal production as 0.25 mg m−2 y−1 between 100 and 1200 m (0.6 and 0.5 mg m−2 y−1 between 450 and 1200 m).
Soil nitrogen transformations on a subantarctic island
Authors: Smith V. R. , Steenkamp Marianna
Published: December 2007

The vascular vegetation of a mire-grassland community on Marion Island (47°S, 38°E) takes up c. 158 mg N m−2 d−1 in summer. Bryophytes take up c. 36 mg N m−2 d−1 during their peak growth period. Since inputs of N through precipitation and biological fixation are negligible, mineralization of organic N must have supplied the bulk of this N. From changes in peat inorganic N levels and rates of uptake by the vegetation we estimate mean mineralization rates of 178 mg N m−2 d−1 in summer and 55 mg N m−2d−1 in winter. In situ incubation
of peat give a maximum mineralization rate of 48 mg N m−2 d−1. At this rate the small (700 mg m−2) pool of available N in the upper 25 cm of peat would be depleted by the vascular vegetation in about seven days and bryophytes would deplete the available N pool in the top 25 mm in two days. Hence the rate of N mineralization measured by incubation is much too low to account for the fluctuations in concentrations of inorganic N in the peat and the amounts taken up by the vegetation. This may be due to losses through denitrification or to the fact that soil macroinvertebrates were excluded from the incubation.
Whither Whaling?
Authors: Gambell Ray
Published: December 2007

In 1972 the United Nations Conference on the Human Environment called for a ten year moratorium on commercial whaling. The International Whaling Commission (IWC, then made up of 14 member governments) did not accept this resolution, taking the view that regulation by species and stocks was the more practical method of whale conservation. In the following years it reduced catches, introduced a new management procedure, and embarked on an international decade of cetacean research.
James Ross Basin workshop
Authors: Feldmann Rodney M.
Published: December 2007

The rocks of the James Ross Basin consist of a 6 km-thick, relatively complete sequence of Early Cretaceous-Eocene marine sediments, which are remarkably well exposed over Seymour, Vega, James Ross, and Snow Hill islands. Throughout most of the sequence, macrofossils and microfossils are extremely abundant and diverse.
Maximum dive depths attained by South Georgia diving petrel Pelecanoides georgicus at Bird Island, South Georgia
Authors: Prince P. A. , Jones M.
Published: December 2007

Maximum dive depths have been recorded for a number of sea-bird species using simple lightweight capillary gauges (Burger & Wilson 1988). So far these studies have been confined to penguins (Montague 1985, Seddon & van Heezik 1990, Whitehead 1989, Wilson & Wilson 1990, Scolaro & Suburo 1991), alcids (Burger & Simpson 1986, Burger & Powell 1988, Harris et al. 1990, Burger 1991) and cormorants (Burger 1991, Wanless et al. 1991).
Late Quaternary glaciation and deglaciation of the Bunger Hills, Antarctica
Authors: Adamson Donald A. , Colhoun Eric A.
Published: December 2007

The Bunger Hills were covered by the Antarctic Ice Sheet during the last glaciation. During deglaciation the ice sheet margin collapsed into the marine inlets and the sea entered the oasis before 7.7 ka BP. Raised beaches occur widely below 8.5 m and indicate uplift at 1.4 m ka−1 during the middle and late Holocene. After the coastal inlets were formed, the Edisto Ice Tongue and Apfels Glacier still impinged on land margins in the west of the oasis. Two sets of marginal moraines were formed; the Older Edisto Moraines after 6.2 ka BP and the Younger Edisto Moraines during the last few centuries. The margins of the Antarctic Ice Sheet and Apfels Glacier in the south have maintained their present positions since at least 5.6 ka BP and probably 10 ka BP.
Otolith structural and chemical analyses: the key to resolving age and growth of the Antarctic silverfish, Pleuragramma antarcticum
Authors: Radtke Richard L. , Hubold Gerd , Folsom Scott D. , Lenz Petra H.
Published: December 2007

The various life history stages of the Weddell Sea population of Pleuragramma antarcticum were sampled to investigate life-history patterns of this ecologically important polar fish. Otoliths were examined for size, morphology and microstructure. Age determination of Antarctic fishes has proved to be difficult because of small ambient temperature fluctuations. External and internal examination of otoliths by scanning electron microscopy revealed internal increments (assumed to be daily) and hatching marks. Back calculation of hatching dates from otolith increments, suggested a hatching season from September-November, with recruitment to the adult population at three to five years of age. Growth data conformed well to the von Bertalanffy equation. Fish grew slowly, with the largest fish attaining ages of more than 30 years. A multivariate mathematical model relating age to otolith morphometrics and fish size proved reliable, making it possible to age large sample sizes of fish. Limited elemental microprobe data obtained from two otoliths demonstrated patterns which may be useful in indicating the environmental life history of individual fish. These collective data suggest that the ecological importance of populations of Pleuragramma antarcticum is most likely due to a long life span and high lifetime reproduction rate.
Taxonomy of six Antarctic anascan Bryozoa
Authors: Hayward P. J. , Ryland J. S.
Published: December 2007

Six species of anascan cheilostome Bryozoa are described from Antarctica. Apiophragma gen.nov. is introduced for Megapora hyalina Waters, 1904. Cellaria dennanti Waters, 1904 non MacGillivray, 1895 is redescribed as Swanomia belgica sp.nov. Paramawsonia Androsova, 1972 is restricted to its type species, Cellaria dennanti MacGillivray, 1985. Micropora notialis sp.nov. is distinguished from M. brevissima Waters, 1904. Two new species are described in the genus Cellaria.
Antarctic data management
Authors: Clarke Drew
Published: December 2007

Antarctic science is inter-disciplinary in character, multi-national in execution, and globally relevant. Data management in this environment must be examined from political, scientific and economic perspectives. The Antarctic Treaty calls on parties to exchange and make freely available scientific observations and results from Antarctica, so establishing the political context for addressing data management. The scientific context arises from the increasingly large and complex issues being addressed, including environmental monitoring and global change programmes, while the economic context considers data and information as the primary assets derived from Antarctic expenditure.
The phylogeny of bacteria from a modern Antarctic refuge
Authors: Franzmann P. D. , Dobson S. J.
Published: December 2007

The 16S rRNAs of nine new species of prokaryotes, that had been isolated from four lakes of the Vestfold Hills, have been sequenced. These sequences were compared with those of their closest taxonomic relatives available from publicly available databases. The Antarctic species were of wide diversity with representatives from the domains Archaea and Bacteria (sensu Woese). Generally, they were most closely related to organisms from marine environments. The sequence dissimilarity between the rRNA sequences of the Antarctic strains and their nearest known relatives suggest they diverged from each other much earlier than the establishment of their modern Antarctic habitat. The conserved nature of the 16S rRNA molecule suggests it may not be as useful for detecting evolutionary change in Antarctic prokaryotes as distinct from non-Antarctic prokaryotes. Although the optimal temperature for growth of each species is well above the temperature of its environment, each has a reduced optimal temperature for growth when compared with its taxonomic counterpart from non-Antarctic environments. The vast majority of Antarctic prokaryotes remains to be described.