Monitoring Phase Transformations in Intact Tablets of Trehalose by FT-Raman Spectroscopy

The purpose of this study is to monitor phase transformations in intact trehalose tablets using FT-Raman spectroscopy. Tablets of trehalose dihydrate, amorphous trehalose (obtained by freeze-drying aqueous trehalose solutions), and anhydrous trehalose (β-trehalose) were prepared. The tablets were exposed to different conditions [11% and 0% RH (60°C); 75% RH (25°C)] and monitored periodically over 96 h using Raman spectroscopy. Within 96 h of storage, the following phase transformations were observed: (1) trehalose dihydrate → β-trehalose (11% RH, 60°C), (2) trehalose dihydrate → α-trehalose (0% RH, 60°C), (3) β-trehalose → trehalose dihydrate (75% RH, 25°C), and (4) amorphous trehalose → trehalose dihydrate (75% RH, 25°C). FT-Raman spectroscopy was a useful technique to identify the solid form and monitor multiple-phase transformations in intact trehalose tablets stored at different conditions.     

Phase Transformations in a Human Tooth Tissue at the Initial Stage of Caries

The aim of the paper is to study phase transformations in solid tissues of the human teeth during the development of fissure caries by Raman and fluorescence microspectroscopy. The study of the areas with fissure caries confirmed the assumption of the formation of a weak interaction between phosphate apatite enamel and organic acids (products of microorganisms). The experimental results obtained with by Raman microspectroscopy showed the formation of dicalcium phosphate dihydrate - CaHPO₄-2H₂O in the area of mural demineralization of carious fissure. A comparative analysis of structural and spectroscopic data for the intact and carious enamel shows that emergence of a more soluble phase - carbonate-substituted hydroxyapatite - is typical for the initial stage of caries. It is shown that microareas of dental hard tissues in the carious fissure due to an emerging misorientation of apatite crystals have a higher fluorescence yield than the area of the intact enamel. These areas can be easily detected even prior to a deep demineralization (white spot stage) for the case of irreversibly changed organomineral complex and intensive removal of the mineral component.     

Nonequilibrium Pathways during Electrochemical Phase Transformations in Single Crystals Revealed by Dynamic Chemical Imaging at Nanoscale Resolution

The energy density of current batteries is limited by the practical capacity of the positive electrode, which is determined by the properties of the active material and its concentration in the composite electrode architecture. The observation in dynamic conditions of electrochemical transformations creates the opportunity of identifying design rules toward reaching the theoretical limits of battery electrodes. But these observations must occur during operation and at multiple scales. They are particularly critical at the single‐particle level, where incomplete reactions and failure are prone to occur. Here, operando full‐field transmission X‐ray microscopy is coupled with X‐ray spectroscopy to follow the chemical and microstructural evolution at the nanoscale of single crystals of Li_1+xMn_2–xO₄, a technologically relevant Li‐ion battery electrode material. The onset and crystallographic directionality of a series of complex phase transitions are followed and correlated with particle fracture. The dynamic character of this study reveals the existence of nonequilibrium pathways where phases at substantially different potentials can coexist at short length scales. The results can be used to inform the engineering of particle morphologies and electrode architectures that bypass the issues observed here and lead to optimized battery electrode properties.     

Adjuvant Chemotherapy with Docetaxel,Cisplatin, and Continuous-Infusion 5-Fluorouracil for Gastric Cancer: A Phase II Study

PURPOSE: This study evaluated the efficacy and safety of adjuvant chemotherapy with the docetaxel plus cisplatin and 5-fluorouracil (5-FU) (DCF) regimen in patients with gastric cancer. PATIENTS AND METHODS: Thirty-two patients with gastric or gastroesophageal junction cancer were enrolled in this study after undergoing radical resection. The patients received the following chemotherapy: docetaxel (60 mg/m²) on day 1, cisplatin (12 mg/m² per day) on days 1 to 5, and 5-FU (2500 mg/m²) continuous infusion for 120 hours, repeated every 3 weeks for six cycles. The primary end point was disease-free survival (DFS). RESULTS: The median DFS was 17.0 months. The 1-year DFS was 72%, and the 2-year DFS was 37.5%. The median overall survival was 28.0 months. Using univariate analysis, the technique of lymph node dissection was a predictor for postoperative relapse. The median DFS was 15.0 months in the D1 group and 18.0 months in the D2 group (P = .043). The most frequent grade 3/4 adverse events were neutropenia (56.25%), diarrhea (9.38%), nausea (6.25%), and vomiting (6.25%); 12.5% of patients developed febrile neutropenia. There were no chemotherapy-related deaths. CONCLUSIONS: The modified DCF regimen is an effective adjuvant chemotherapy in gastric cancer. Hematologic toxicity was frequent but manageable. This regimen merits further investigation.     

Transformations in isolated polyhooks.

Polyhooks from certain non-flagellated mutants of Salmonella and Escheriohia coli are known to be helix-shaped under physiological conditions. However, two non-helical forms were found to occur in isolated polyhooks under appropriate conditions. One form is straight, and appeared when the pH was decreased to 3.2 or lower. The helical-to-straight transformation was reversible. The other form is a doughnut with a fairly constant diameter of above 0.1 μm, which was produced when polyhooks were heated at 75 °C in the absence of salts.     

在变化中延续—华盛顿开放空间系统的规划历程探析

通过研究华盛顿开放空间系统的历史规划,概述了建都伊始朗方制定的彰显帝国雄心的勒诺特式宏伟蓝图,工业化时期解决城市问题的麦克米兰计划,以及后工业化时期多元价值集于一体的开放空间系统优化三大规划阶段,展示了华盛顿开放空间系统不断生长、日趋完善的发展历程。并分析时代变化背景下各阶段开放空间系统规划的策略要点,阐释漫长规划历程中体现出的高度延续特征,总结出华盛顿开放空间系统的规划经验,为中国的城市建设提供借鉴和参考。     

Transformations of fertilizer nitrogen in soil

Summary Five crops of oats were grown over a 14-month period on a Chester silt loam soil fertilized with N¹⁵-labelled (NH₄)₂SO₄. All plant material from the first four crops was returned to the soil. Following a fifth crop, oat tops and roots were harvested, and the soil was subjected to repeated extractions by autoclaving in 0.01M CaCl₂. The distribution of N¹⁵ and of indigenous soil N among chemical fractions of the extracts, and in the acid-soluble and acid-soluble and acid-insoluble portions of the soil residues following 0.01M CaCl₂ extraction, was remarkably similar. Since appreciable equilibrations between added N¹⁵ and the more resistant forms of soil organic N is unlikely, it is postulated that fertilizer N became incorporated in newly-formed complexes, similar to those already present in the soil. This view is in harmony with the finding that percentage removals of total and N¹⁵-labelled N remained almost the same, even with recovery of approximately 55 per cent of the amounts originally present. N mineralization capacity of the soil was reduced appreciably as a result of extraction.     

Spontaneously Occurring Bacterial Transformations in Mice

In 1963, it was reported that deoxyribonucleic acid (DNA)-mediated transformations could take place spontaneously between genetically distinguishable pneumococci growing in a living host, the mouse. It was found in the present study that such transformations could be increased in frequency if infected animals were treated with a drug which kills only one of the two infecting strains. The frequency of in vivo transformations was also increased if the infection was prolonged. Interspecific transformation between pneumococci and streptococci without the addition of purified DNA was demonstrated both in vitro and in vivo. These results make it seem more likely that DNA-mediated transformations occur in nature.     

Fungal Transformations of Triparanol

Fungal transformations of triparanol, a hypercholesterolemic drug, were studied in Lagenidium giganteum and Lagenidium callinectes. The products were identified by combined gas chromatography-mass spectrometry. Two metabolites were observed from each organism; only one of the metabolites was found in both organisms.     

Microbial Transformations of Selenium

Resting cell suspensions of a strain of Corynebacterium isolated from soil formed dimethyl selenide from selenate, selenite, elemental selenium, selenomethionine, selenocystine, and methaneseleninate. Extracts of the bacterium catalyzed the production of dimethyl selenide from selenite, elemental selenium, and methaneseleninate, and methylation of the inorganic Se compounds was enhanced by S-adenosylmethionine. Neither trimethylselenonium nor methaneselenonate was metabolized by the Corynebacterium. Resting cell suspensions of a methionine-utilizing pseudomonad converted selenomethionine to dimethyl diselenide. Six of 10 microorganisms able to grow on cystine used selenocystine as a sole source of carbon and formed elemental selenium, and one of the isolates, a pseudomonad, was found also to produce selenide. Soil enrichments converted trimethylselenonium to dimethyl selenide. Bacteria capable of utilizing trimethylselenonium, dimethyl selenide, and dimethyl diselenide as carbon sources were isolated from soil.     

Bacterial Transformations of Naphthothiophenes

Naphthothiophenes are minor components of fossil fuels, and they can enter the environment from oil spills. Naphtho[2,1-b]thiophene, naphtho[2,3-b]thiophene, and 1-methylnaphtho[2,1-b]thiophene were synthesized and used in biodegradation studies with 1-methylnaphthalene (1-MN)-degrading Pseudomonas strains W1, F, and BT1. Cultures were incubated with one of the naphthothiophenes with or without 1-MN, acidified, and extracted with CH(inf2)Cl(inf2). The extracts were analyzed by gas chromatography with flame photometric and mass detectors to characterize sulfur-containing metabolites and with an atomic emission detector for quantification. Only strain W1 was able to grow on naphtho[2,1-b]thiophene, but strains F and BT1 cometabolized this compound if 1-MN was present. 1-MN was required by all three strains to metabolize naphtho[2,3-b]thiophene, which was more resistant to biodegradation than the [2,1-b] isomer. Two metabolites of naphtho [2,1-b]thiophene were purified, analyzed by (sup1)H nuclear magnetic resonance spectroscopy, and found to be 4-hydroxybenzothiophene-5-carboxylic acid (metabolite I) and 5-hydroxybenzothiophene-4-carboxylic acid (metabolite II). In cultures of strain W1 grown for 7 days on 52 (mu)mol of naphtho[2,1-b]thiophene, >84% of the substrate was degraded and metabolites I and II accounted for 19 and 9%, respectively, of the original amount of naphtho[2,1-b]thiophene. When 1-MN was present, strain W1 degraded >97% of the naphtho[2,1-b]thiophene and similar amounts of metabolite II were produced, but metabolite I did not accumulate. 1-MN was shown to promote the further degradation of metabolite I, but not of metabolite II, by strain W1. Thus, 1-MN enhanced the biodegradation of naphtho[2,1-b]thiophene. Approximately 70% of the 1-methylnaphtho [2,1-b]thiophene added to cultures of strain W1 with 1-MN was recovered as 4-hydroxy-3-methylbenzothiophene-5-carboxylic acid, the 3-methyl analog of metabolite I. The methyl substitution hindered further metabolism of 3-methyl-metabolite I even in the presence of 1-MN. Cometabolism of naphtho[2,3-b]thiophene yielded two products that were tentatively identified as 5-hydroxybenzothiophene-6-carboxylic and 6-hydroxybenzothiophene-5-carboxylic acids.     

Sensorimotor Transformations in the Zebrafish Auditory System

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Evolutionary Transformations of Ontogenesis in Anuran Amphibians

A review of the recent published data on ontogenesis of direct developing and marsupial frogs. The development of these representatives of anuran amphibians seems to be evolutionary advanced and considerably differs from the development of species traditionally used in amphibian embryology.     

Plasmon-Assisted Transformations in Metal-Amorphous Chalcogenide Light-Sensitive Nanostructures

Laser irradiation induced changes of optical parameters in the layered structures which consist of gold nanoparticles and amorphous As₂S₃ were investigated and modelled in the framework of Bruggeman approximation for localised plasmons with aim to show the influence of plasmon fields on the optical recording process.     

Transformations of Progesterone by Basidiomycetes

A total of 254 basidiomycete cultures have been examined for their action on progesterone. Of these, 54 showed transformation products by thin-film and gas-liquid chromatography. The major product formed by eight of these organisms acting on progesterone has been isolated and identified.     

Melanesian Kastom and Its Transformations

Editorial Board Note: In 2006, the Discipline Group of Anthropology and Sociology at The University of Western Australia hosted a symposium, ‘Anthropology in the West: 1956–2006’, to celebrate the 50th anniversary of the founding of the then Department of Anthropology by the late Ronald Berndt and his wife, Catherine, whose contributions to anthropology were a major focus of the symposium. Symposium participants also documented contributions made by UWA staff and students from Anthropology and Sociology within and beyond Australian social science. A notable theoretical focus on kastom in the work of Robert Tonkinson, who in 1984 succeeded Professor Berndt in the Departmental Chair, was the topic of Lamont Lindstrom's paper, published here in a fuller, revised and fully refereed version. We intend to publish further papers from the symposium in later issues of Anthropological Forum.

If Ronald and Catherine Berndt are ancestral spirits haunting Anthropology and Sociology at The University of Western Australia some 50 years after the founding of the Department of Anthropology, their student, Bob Tonkinson, still happily with us, is their intellectual descendant and institutional heir. As in the case of the Berndts, issues relating to social change, religion and values, and, in particular, the politics of tradition have loomed large in Tonkinson's career. I trace, in this retrospective essay, the rise to prominence of an anthropology of Melanesian tradition and, more specifically, Tonkinson's contribution, notably his analyses of tradition's ‘symbiotic’ relations with Christianity, its identity functions, its local versus its national significance, and its relations with evolving anthropological theories of culture in a shrinking world. Tonkinson's Vanuatu research, which began among Ambrym Island emigrants, has spanned, over the past forty years or so, many notable transformations: from New Hebrides to Vanuatu; from modernisation theory to world systems and globalisation; and from tradition to kastom.