YP_5O_(14):Er~(3+),Tm~(3+)晶体的合成

研究了水热法合成晶体,浓度配比、生长温度对晶体生长习性的影响.合成了一系列化学计量比的Y_(1-x-0.3)Er_(0.3)Tm_xP_5O_(14)(x=0.01～0.1)晶体,观察和分析了晶体的缺陷及成因,测定和讨论了晶体结构.

Trajectory Mapping ("TM''): A New Non-Metric Scaling Technique

Trajectory Mapping "TM'' is a new scaling technique designed to recover the parameterizations, axes, and paths used to traverse a feature space. Unlike Multidimensional Scaling (MDS), there is no assumption that the space is homogenous or metric. Although some metric ordering information is obtained with TM, the main output is the feature parameterizations that partition the given domain of object samples into different categories. Following an introductory example, the technique is further illustrated using first a set of colors and then a collection of textures taken from Brodatz (1966).

Keeping Secrets in Hardware: the Microsoft Xbox(TM) Case Study

This paper discusses the hardware foundations of the cryptosystem employed by the Xbox(TM) video game console from Microsoft. A secret boot block overlay is buried within a system ASIC. This secret boot block decrypts and verifies portions of an external FLASH-type ROM. The presence of the secret boot block is camouflaged by a decoy boot block in the external ROM. The code contained within the secret boot block is transferred to the CPU in the clear over a set of high-speed busses where it can be extracted using simple custom hardware. The paper concludes with recommendations for improving the Xbox security system. One lesson of this study is that the use of a high-performance bus alone is not a sufficient security measure, given the advent of inexpensive, fast rapid prototyping services and high-performance FPGAs.

Mapeamento e descrição do padráo de uso e cobertura da terra em municípios do sudoeste goiano a partir de imagens orbitais TM/Landsat-5.

A partir dos anos 1970, a ocupação pelo homem do espaço do centro-oeste brasileiro apresentou um elevado crescimento devido a políticas de expansão agrícola. Este fato ocorreu por meio do alto grau de mecanização agrícola e aplicação de fertilizantes, visando elevados níveis de produção em diversas localidades, como o sudoeste do Estado de Goiás. Tal predicado da alta produtividade mantém-se até os dias atuais, indicando a grande intensidade da dinâmica de uso e cobertura das terras nesta região. Desta forma, tornase necessário o conhecimento da dinâmica e distribuição espacial dos padrões de uso e cobertura da terra, podendo fornecer subsídios a ações de planejamento agrícola sobre o espaço em alguns municípios do sudoeste goiano. Para isto, imagens orbitais do satélite Landsat TM-5 foram adquiridas em diferentes períodos do ciclo agrícola ao longo de 2007. Informações complementares acerca do uso regional foram utilizadas para apoiar a interpretação e classificação, principalmente a partir dos dados obtidos em campo. Os mapas de uso e cobertura da terra para os municípios de Rio Verde, Acreúna, Santo Antônio da Barra, Santa Helena de Goiás, Montividiu e Paraúna foram obtidos utilizando ferramentas do programa Spring 4.3.3 como a segmentação de imagens, bem como o classificador semi-automático Bhattacharya Distance, sendo estabelecidas dez classes temáticas, com base na legenda proposta pelo IBGE e Corine. A análise multitemporal, assim como a segmentação mostraram-se eficientes na distinção das classes de uso e cobertura da terra da região. A classe de uso destinada ao plantio da soja apresentou o maior percentual da área, mudando para culturas safrinha, solo exposto ou pousio no inverno. Outras classes também merecem destaque como a Pastagem e a Cana-de-açúcar, que apresentaram distribuição espacial bastante concentrada. Este mapeamento fornece subsídios ao planejamento do uso e ocupação das terras na região, considerando os aspectos ambientais e sociais, assegurando maior produtividade agrícola, visando um manejo sustentável das terras e a qualidade de vida ao homem do campo.

Levantamento de reconhecimento de baixa intensidade dos solos da Reserva Extrativista do Alto Juruá, Marechal Thaumaturgo, Acre.

Este trabalho foi executado pela Universidade Federal do Acre (Ufac) em cooperação com a Fundação de Tecnologia do Estado do Acre (Funtac), Embrapa Acre e Universidade Estadual de Campinas (Unicamp). O levantamento de solos, em nível de reconhecimento de baixa intensidade, compreende a Reserva Extrativista do Alio Juruá, localizada entre as coordenadas geográficas de 08 0 45' e 09 0 45' 8, de latitude sul e 72 0 00' e 730 00' W, longitude a oeste. A metodologia utilizada é a mesma que a Embrapa Solos vem utilizando em estudos similares. Realizaram-se análises físicas e químicas no Laboratório de Solos da Embrapa Acre e as análises de ataque sulfúrico no laboratório da Embrapa Solos. No desenvolvimento da prospecção pedológica foram utilizadas imagens TM 345/Landsat - 5, 1992, tratadas no Laboratório de Processamento de Informações Georreferenciadas da Unicamp, na escala de 1:100.000 e 1:200.000. Os mapas finais de solos foram elaborados na escala de 1:250.000, com unidades de mapeamento em associações, dada a limitação da escala. Os principais solos encontrados na área são: Alissolos, Luvissolos, Cambissolos, Chemossolos, Gleissolos e Neossolos. Exduindo a alta fertilidade, os solos da Reserva Extrativista do Alto Juruá apresentam sérias restrições de uso quando se consideram as condições de relevo em que estão inseridos. A área apresenta relevo ondulado a forte ondulado e solos com alto gradiente textural, implicando em alta susceptibilidade à erosão. Observou-se, em algumas áreas de relevo forte ondulado e sobre a ocorrência de Cambissolo e floresta tropical aberta, erosão laminar ligeira. No caso de retirada da floresta natural, este processo erosivo irá se intensificar, causando danos irreversíveis ao solo e, conseqüentemente, ao ambiente.

Potencialidades da pimenta-de-macaco (Piper aduncum L.): características gerais e resultados de pesquisa.

A diversidade da flora brasileira, em especial a da Região Amazônica, apresenta um imenso potencial para a produção de compostos secundários de plantas, que têm sido demandados continuamente pela indústria nas últimas décadas, devido ao incremento da utilização de produtos naturais na agropecuária. Estima-se que existam 500 mil espécies de plantas no mundo, sendo .16% delas encontradas na florésta amazônica. No entanto, a pesquisa de substâncias ativas derivadas de plantas no Brasil ainda é muito incipiente. Mesmo considerando os incrementos significativos da pesquisa nas últimas duas décadas, há, evidentemente, uma grande lacuna de conhecimento da nossa flora a ser preenchida. A partir da década de 90 a Embrapa Acre vem intensificando atividades de pesquisa no sentido de viabilizar a utilização de recursos não-madeireiros das florestas do Acre. Destacam-se dentre eles, produtos promissores oriundos de piperáceas, como o óleo essencial rico em safrol, produzido a partir da biomassa da Piper hispidinervum e, mais recentemente, o óleo essencial de P. aduncum com altos teores de dilapiol. P. aduncum é uma espécie de planta que vem apresentando um crescente interesse, principalmente quanto à extração em escala industrial do seu óleo essencial. A elaboração deste documento tem como finalidade contribuir para o conhecimento da potencialidade do emprego dessa planta na elaboração de produtos para o controle de pragas de interesse agropecuário e utilização na medicina humana.

Fármacos que têm por alvo o epigenoma

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

Practice Links [Issue 53, June 2013]

Practice Links is a free e-publication for practitioners working in Irish social services, voluntary and nongovernmental sectors. Practice Links was created to enable practitioners to keep up-to-date with new publications, electronic resources and conference opportunities. Issue 53 includes reviews of research on medication for schizophrenia and the impact of housing improvements on health.

Invasive fungal infections among organ transplant recipients: results of the Transplant-Associated Infection Surveillance Network (TRANSNET).

BACKGROUND: Invasive fungal infections (IFIs) are a major cause of morbidity and mortality among organ transplant recipients. Multicenter prospective surveillance data to determine disease burden and secular trends are lacking. METHODS: The Transplant-Associated Infection Surveillance Network (TRANSNET) is a consortium of 23 US transplant centers, including 15 that contributed to the organ transplant recipient dataset. We prospectively identified IFIs among organ transplant recipients from March, 2001 through March, 2006 at these sites. To explore trends, we calculated the 12-month cumulative incidence among 9 sequential cohorts. RESULTS: During the surveillance period, 1208 IFIs were identified among 1063 organ transplant recipients. The most common IFIs were invasive candidiasis (53%), invasive aspergillosis (19%), cryptococcosis (8%), non-Aspergillus molds (8%), endemic fungi (5%), and zygomycosis (2%). Median time to onset of candidiasis, aspergillosis, and cryptococcosis was 103, 184, and 575 days, respectively. Among a cohort of 16,808 patients who underwent transplantation between March 2001 and September 2005 and were followed through March 2006, a total of 729 IFIs were reported among 633 persons. One-year cumulative incidences of the first IFI were 11.6%, 8.6%, 4.7%, 4.0%, 3.4%, and 1.3% for small bowel, lung, liver, heart, pancreas, and kidney transplant recipients, respectively. One-year incidence was highest for invasive candidiasis (1.95%) and aspergillosis (0.65%). Trend analysis showed a slight increase in cumulative incidence from 2002 to 2005. CONCLUSIONS: We detected a slight increase in IFIs during the surveillance period. These data provide important insights into the timing and incidence of IFIs among organ transplant recipients, which can help to focus effective prevention and treatment strategies.

Death on a road (Dem. 23.53)

Scholarly consensus holds that a law quoted in Demosthenes (23.53) permitted one to kill a highway robber who had lain in ambush and attacked one on a road. But the relevant phrase says nothing explicit about ambush. Modern interpretation derives from Harpocration and other ancient authorities. It is argued here that they were mistaken and that the phrase referred to those who inadvertently killed a fellow traveler while overtaking on a road.' The new interpretation may offer another way to think about the encounter between Oedipus and Laius.

Structure and denaturation of 4-chlorobenzoyl coenzyme A dehalogenase from Arthrobacter sp. strain TM-1

The secondary structure of the trimeric protein 4-chlorobenzoyl coenzyme A dehalogenase from Arthrobacter sp. strain TM-1, the second of three enzymes involved in the dechlorination of 4-chlorobenzoate to form 4-hydroxybenzoate, has been examined. E(mM) for the enzyme was 12.59. Analysis by circular dichroism spectrometry in the far uv indicated that 4-chlorobenzoyl coenzyme A dehalogenase was composed mostly of alpha-helix (56%) with lesser amounts of random coil (21%), beta-turn (13%) and beta-sheet (9%). These data are in close agreement with a computational prediction of secondary structure from the primary amino acid sequence, which indicated 55.8% alpha-helix, 33.7% random coil and 10.5% beta-sheet; the enzyme is, therefore, similar to the 4-chlorobenzoyl coenzyme A dehalogenase from Pseudomonas sp. CBS-3. The three-dimensional structure, including that of the presumed active site, predicted by computational analysis, is also closely similar to that of the Pseudomonas dehalogenase. Study of the stability and physicochemical properties revealed that at room temperature, the enzyme was stable for 24 h but was completely inactivated by heating to 60 degrees C for 5 min; thereafter by cooling at 1 degrees C min(-1) to 45 degrees C, 20.6% of the activity could be recovered. Mildly acidic (pH 5.2) or alkaline (pH 10.1) conditions caused complete inactivation, but activity was fully recovered on returning the enzyme to pH 7.4. Circular dichroism studies also indicated that secondary structure was little altered by heating to 60 degrees C, or by changing the pH from 7.4 to 6.0 or 9.2. Complete, irreversible destruction of, and maximal decrease in the fluorescence yield of the protein at 330-350 nm were brought about by 4.5 M urea or 1.1 M guanidinium chloride. Evidence was obtained to support the hypothetical three-dimensional model, that residues W140 and W167 are buried in a non-polar environment, whereas W182 appears at or close to the surface of the protein. At least one of the enzymes of the dehalogenase system (the combined 4-chlorobenzoate:CoA ligase, the dehalogenase and 4-hydroxybenzoyl coenzyme A thioesterase) appears to be capable of association with the cell membrane.

Spatial Demultiplexing in the sub-millimeter wave band using multlayer free-standing frequency selective surfaces

In this paper, we show that a multilayer freestanding slot array can be designed to give an insertion loss which is significantly lower than the value obtainable from a conventional dielectric backed printed frequency selective surface (FSS). This increase in filter efficiency is highlighted by comparing the performance of two structures designed to provide frequency selective beamsplitting in the quasioptical feed train of a submillimeter wave space borne radiometer. A two layer substrateless FSS providing more than 20 dB of isolation between the bands 316.5â??325.5 GHz and 349.5â??358.5 GHz, gives an insertion loss of 0.6 dB when the filter is orientated at 45 incidence in the TM plane, whereas the loss exhibited by a conventional printed FSS is in excess of 2 dB. A similar frequency response can be obtained in the TE plane, but here a triple screen structure is required and the conductor loss is shown to be comparable to the absorption loss of a dielectric backed FSS. Experimental devices have been fabricated using a precision micromachining technique. Transmission measurements performed in the range 250â??360 GHz are in good agreement with the simulated spectral performance of the individual periodic screens and the two multilayer freestanding FSS structures.

Numerical analysis of bodyworn UHF antenna systems

Bodyworn antennas are found in a wide range of medical, military and personal communication applications, yet reliable communication from the surface of the human body still presents a range of engineering challenges. At UHF and microwave frequencies, bodyworn antennas can suffer from reduced efficiency due to electromagnetic absorption in tissue, radiation pattern fragmentation and variations in feed-point impedance. The significance and nature of these effects are system specific and depend on the operating frequency, propagation environment and physical constraints on the antenna itself. This paper describes how numerical electromagnetic modelling techniques such as FDTD (finite-difference time-domain) can be used in the design of bodyworn antennas. Examples are presented for 418 MHz, 916 .5 MHz and 2 . 45 GHz, in the context of both biomedical signalling and wireless personal-area networking applications such as the Bluetooth(TM)* wireless technology.

Avandia (TM) - From molecule to market for type 2 diabetes.

Type 2 diabetes is a disease fast approaching epidemic proportions throughout the world. From insulin sensitizers to PPARg agonists, the lecture will outline the successful medicinal chem. and biol. strategy underpinning the discovery and selection of Avandia, an innovative new medicine for this disease.