Synthesis of new (Bi, La)(3)MSb(2)O(11) phases (M = Cr, Mn, Fe) with KSbO(3)-type structure and their magnetic and photocatalytic properties

Synthesis and structure of new (Bi, La)(3)MSb(2)O(11) phases (M = Cr, Mn, Fe) are reported in conjunction with their magnetic and photocatalytic properties. XRD refinements reflect that Bi(3)CrSb(2)O(11), Bi(2)LaCrSb(2)O(11), Bi(2)LaMnSb(2)O(11) and Bi(2)LaFeSb(2)O(11) adopt KSbO(3)-type structure (space group, Pn (3) over bar). The structure can be described through three interpenetrating networks where the first is the (M/Sb)O(6) octahedral network and other two are the identical networks having Bi(6)O(4) composition. The magnetic measurements on Bi(2)LaCrSb(2)O(11) and Bi(2)LaMnSb(2)O(11) show paramagnetic behaviour with magnetic moments close to the expected spin only magnetic moments of Cr(+3) and Mn(+3). The UV-Visible diffuse reflectance spectra are broad and indicate that these materials possess a bandgap of similar to 2 eV. The photocatalytic activity of these materials has been investigated by degrading Malachite Green (MG) under exposure to UV light.

Recovery of mutans streptococci on MSB, SB-20 and SB-20M agar media

Objective: The recovery of mutans streptococci in saliva and dental biofilm samples depends, in part, on the culture medium used. In this study, we compared (i) the culture media Sucrose-Bacitracin agar (SB-20), Modified SB-20 (SB-20M) and Mitis Salivarius Bacitracin agar (MSB) in the count of colony forming units (cfu) of mutans streptococci and (ii) in the morphological and biochemical differentiation between Streptococcus mutans and Streptococcus sobrinus. Design: Samples of non-stimulated saliva from 20 children were plated on SB-20, SB-20M and MSB, and incubated in microaerophilia at 37 °C for 72 h. Identification of microorganisms was based on analysis of colony morphology under stereomicroscopy. The biochemical identification of colonies was done by biochemical tests using sugar fermentation, resistance to bacitracin and hydrogen peroxide production. Results: There was no significant difference (p > 0.05) in the number of cfu of mutans streptococci recovered on SB-20 and SB-20M agar. Comparing the media, SB-20 and SB-20M yielded a larger number of mutans streptococci colonies (p < 0.05) and were more effective than MSB in the identification of S. sobrinus (p < 0.05), but not of S. mutans (p > 0.05). Conclusion: There was no significant difference between SB-20 and SB-20M culture media in the count of mutans streptococci, demonstrating that the replacement of sucrose by coarse granular cane sugar did not alter the efficacy of the medium. Compared with MSB, SB-20 and SB-20M allowed counting a larger number of mutans streptococci colonies and a more effective morphological identification of S. sobrinus. © 2012 Elsevier Ltd.

MSB: Una aplicacion WWW para generación de resúmenes de comportamiento

La disponibilidad en Internet de grandes volúmenes de información en los que se basan decisiones relacionadas con el funcionamiento de sistemas dinámicos hace que cada vez sean más necesarios métodos efectivos de generación automáti-ca de resumen de información de comportamiento. En este artículo se describe la aplicación MSB (Multimedia Summari-zer of Behavior) como una herramienta software que genera presentaciones multimedia de resumen de comportamiento de sistemas dinámicos para ser presentadas en la Web. MSB usa como entrada datos de comportamiento de fuentes remo-tas (medidos por sensores) que pueden estar disponibles en diferentes servidores Web. Estas fuentes de información se interpretan y resumen usando métodos del campo de la Inteligencia Artificial simulando formas de razonamiento que realizan las personas al resumir información de interés. En el artículo se describe la arquitectura basada en el conocimien-to del sistema MSB y la aplicación desarrollada en el dominio de hidrología sobre comportamiento de cuencas hidrográ-ficas.

Caracterización de la comunidad indígena Mayanhna Amak, zona de règimen especial alto Bocay (RBB) MSB 2010-2013

Este trabajo recoge información obtenida a lo largo de tres años de investigación por parte del equipo de voluntarios que forman el Proyecto de Extensión y Desarrollo Comunitario Amak, PEDCA. Esta iniciativa de jóvenes, surge en el año 2010 con el objetivo de brindar a la comunidad Amak, los conocimientos impartidos en las aulas de clase de forma autogestionaria, organizando, planificando y ejecutando actividades en la zona de manera interdisciplinar y sobre todo, desde los estudiantes de las diferentes carreras que ofrece la UNA. Las Variables contempladas en este estudio son: Marco histórico, Aspectos biofísicos, Morfología rural, Demografía, Población aspecto estático, población aspecto dinámico, Educación, Salud pública, Seguridad pública, Organización comunitaria, Instituciones Gubernamentales, ONGs, Economía y Apreciación comunitaria. Las Herramientas utilizadas fueron: Grupo focal, Entrevista a informantes clave, Censo, Observación Participante, Encuesta, Georreferenciación y Muestreo. La comunidad indígena Mayangna Amak está ubicada la Zona de Régimen Especial Alto Bocay, territorio Mayangna Sauni Bu, reserva de biosfera BOSAWAS. Se encuentra entre las márgenes del río Bocay y el río Amak. El núcleo habitacional consiste en agrupaciones de casas con habitantes de parentesco sanguíneo y en las afueras están ubicadas las zonas de cultivo. Está conformada por 210 familias y 1,213 personas las cuales viven en 130 viviendas. A nivel organizacional tienen su propio sistema de gobierno denominado Gobierno Territorial Indígena (GTI) conformado por un presidente, un secretario y responsables de áreas específicas quienes trabajan en conjunto con organismos e instituciones. Existe a nivel de infraestructura un centro de salud, una escuela primaria y secundaria. La actividad económica más importante es la agricultura, crianza de ganado, caza y pesca. Una de las características que convierten a esta zona en prioritaria es que a pesar de la riqueza cultural y la alta biodiversidad existente, se han desarrollado pocos estudios. Otro aspecto de importancia son las carencias y problemáticas que presenta la zona en cuanto al desarrollo en el acceso a la educación, salud y transporte representando un alto grado de vulnerabilidad en relación a fenómenos naturales, brotes epidemiológicos y seguridad alimentaria.

Analyzing busway station potential capacity under mixed stopping and non-stopping operation

Busway stations are the interface between passengers and services. The station is crucial to line operation as it is typically the only location where buses can pass each other. Congestion may occur here when buses manoeuvring into and out of the platform lane interfere with bus flow, or when a queue of buses forms upstream of the platform lane blocking the passing lane. Further, some systems include operation where express buses do not observe the station, resulting in a proportion of non-stopping buses. It is important to understand the operation of the station under this type of operation and its effect on busway capacity. This study uses microscopic simulation to treat the busway station operation and to analyse the relationship between station potential capacity where all buses stop, and Mixed Potential Capacity where there is a mixture of stopping and non-stopping buses. First, the micro simulation technique is used to analyze the All Stopping Buses (ASB) scenario and then statistical model is tuned and calibrated for a specified range of controlled scenarios of dwell time characteristics Subsequently, a mathematical model is developed for Mixed Stopping Buses (MSB) Potential Capacity by introducing different proportions of express (or non-stopping) buses. The proposed models for a busway station bus capacity provide a better understanding of operation and are useful to transit agencies in busway planning, design and operation.

Analysing busway station capacity under mixed stopping and non-stopping operation

Busway stations are the interface between passengers and services. The station is crucial to line operation as it is typically the only location where buses can pass each other. Congestion may occur here when buses manoeuvring into and out of the platform lane interfere with bus flow, or when a queue of buses forms upstream of the platform lane blocking the passing lane. Further, some systems include operation where express buses do not observe the station, resulting in a proportion of non-stopping buses. It is important to understand the operation of the station under this type of operation and its effect on busway capacity. This study uses microscopic simulation to treat the busway station operation and to analyse the relationship between station potential capacity where all buses stop, and Mixed Potential Capacity where there is a mixture of stopping and non-stopping buses. First, the micro simulation technique is used to analyze the All Stopping Buses (ASB) scenario and then statistical model is tuned and calibrated for a specified range of controlled scenarios of dwell time characteristics Subsequently, a mathematical model is developed for Mixed Stopping Buses (MSB) Potential Capacity by introducing different proportions of express (or non-stopping) buses. The proposed models for a busway station bus capacity provide a better understanding of operation and are useful to transit agencies in busway planning, design and operation.

A ministop band in a single-defect photonic crystal waveguide based on silicon on insulator

This paper reports that a two-dimensional single-defect photonic crystal waveguide in the F-K direction with triangular lattice on a silicon-on-insulator substrate is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. A ministop band (MSB) is observed by the measurement of transmission characteristics. It results from the coupling between the two modes with the same symmetry, which is analysed from the stimulated band diagram by the effective index and the two-dimensional plane wave expansion methods. The parameter working on the MSB is the ratio of the radius of air holes to the lattice constant, r/a. It is obtained that the critical r/a value determining the occurrence or disappearance of MSB is 0.36. When r/a is larger than or equal to 0.36, the MSB occurs. However, when r/a is smaller than 0.36, the MSB disappears.

功能菌强化应急处理苯胺突发污染事故研究

近年来各种环境污染事故频发，据统计仅2001~2003年间，发生的各类环境污染事故就高达5606次，其中水污染事故3235次，占全部的57.7%。这些事故不仅给人民生命财产造成巨大损失，也给生态环境造成严重的破坏。因此开发安全高效的应急处理技术迫在眉睫。本研究以筛选高效苯胺降解菌为基础，通过对高效菌降解性能的研究指导将高效菌作为功能郡主投加到已有生物处理系统强化应急处理苯胺突发污染事故废液，取得了良好的效果。 苯胺高效降解菌AN-P1为红球菌（Rhodococcus sp.），其通过间位途径降解苯胺，AN-P1利用苯胺生长和降解的最佳pH为6，最适浓度为2000 mg/L，最适温度为30 ℃，最佳接种量为0.3‰。AN-P1降解含500 mg/L、1000 mg/L、2000 mg/L苯胺的培养物分别经过28 h、24 h、32 h降解，出水苯胺含量能达到《污水综合排放标准》（GB8978-1996）一级标准。但由于苯胺降解过程中释放了大量氨氮，出水氨氮仍较高未能达标排放。而常规SBR系统应急处理效果较差，苯胺和COD去除率均低于10%，出水未能达标排放。活性碳吸附后的回收和后续处理也会带来操作不变和二次污染问题，且处理后出水往往难于达标排放，尚需进行进一步处理。 生物处理系统应急处理后恢复运行处理效果监测和PCR-DGGE图谱分析显示，用AN-P1菌强化应急处理系统后不仅能快速高效的去除苯胺，而且可以有效保障处理系统对污染物的净化性能，有效的保护系统中的功能微生物免受苯胺毒害。 研究结果表明，从实际处理效果、对原有生物系统性能保护及实际应用操作等多方面考虑，用AN-P1菌强化应急处理苯胺突发污染事故在技术上都是可行的。本研究为应急处理苯胺突然污染事故废液提供了新的方法。 Recent years, environment pollution accidents happened frequently, the data showed that there are 5606 accidents between 2001 and 2003, including 3235 water environment accidents, which is 57.7% of all. These accedents not only caused money lost and life lost but also caused serious damage to the ecologicl environment. So exploring highly-effective and secure methods to solve these accidents is an urgent mission. We screened a highly-effective aniline-degrading bacterium and did some researches on its ability to degrade aniline, in order to guide the emergency treatment of aniline containing wastewater that caused by sudden accident pollution with bioaugmentation. A highly-effective aniline-degrading bacterium AN-P1 was isolate and characterized as Rhodococcus sp. It degrades aniline through meta-cleavage pathway. The optimal pH and temperature for cell growth and aniline degradation were 6 and 30 ℃, respectively, and the opitimal concentration of aniline was 2000 mg/L, the optimal inoculation amount was 0.3‰.It took bacterium AN-P1 only 18 h, 24 h and 32 h, respectively, for the treatment of MSB containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. The bacterium AN-P1 can also remove some of the NH4+-N which caused by aniline degradation. It took bacterium AN-P1 only 10 h, 20 h and 32 h, respectively, for the treatment of wastewater containing 500 mg/L, 1000 mg/L, 2000 mg/L aniline to meet the first grade of national integrated wastewater discharge standard. By combing AN-P1 with regular SBR system, it took only 36 h for the emergency treatment of wastewater containing 2000 mg/L aniline under simulating engineering conditions to meet the discharge standard. While the NH4+-N of effluent can not meet the standard because of the high amount NH4+-N caused by aniline degradation. The regular SBR system was not good at aniline and COD removal. The removal efficiency of which are less than 10%. It cost 67.8 g activated carbon to absorbed 1000 mg aniline. It is inconvenient to transport and use it for the emergency treatment of aniline when the sudden pollution accident happened. Meanwhile, it was complex ad hard to recycle the activated carbon and treat the aniline wastewater get from activated carbon recycling too. Hard to meet the effluent standard was also a problem of activated carbon absorption method. According to the PCR-DGGE profile and removal efficiency of pollutants and COD when the systerm recover from emergency treatment, AN-P1 can efficiently protect the microbial community of regular activated sludge system against the aniline. It proved that combing AN-P1 with regular biological system is a feasible strategy for emergency treatment of aniline sudden pollution accident. The research offered a new way for emergency treatment of aniline sudden pollution accident.

Anti-AIDS agents 81. Design, synthesis, and structure-activity relationship study of betulinic acid and moronic acid derivatives as potent HIV maturation inhibitors.

In our continuing study of triterpene derivatives as potent anti-HIV agents, different C-3 conformationally restricted betulinic acid (BA, 1) derivatives were designed and synthesized in order to explore the conformational space of the C-3 pharmacophore. 3-O-Monomethylsuccinyl-betulinic acid (MSB) analogues were also designed to better understand the contribution of the C-3' dimethyl group of bevirimat (2), the first-in-class HIV maturation inhibitor, which is currently in phase IIb clinical trials. In addition, another triterpene skeleton, moronic acid (MA, 3), was also employed to study the influence of the backbone and the C-3 modification toward the anti-HIV activity of this compound class. This study enabled us to better understand the structure-activity relationships (SAR) of triterpene-derived anti-HIV agents and led to the design and synthesis of compound 12 (EC(50): 0.0006 microM), which displayed slightly better activity than 2 as a HIV-1 maturation inhibitor.

Programming stress-induced altruistic death in engineered bacteria.

Programmed death is often associated with a bacterial stress response. This behavior appears paradoxical, as it offers no benefit to the individual. This paradox can be explained if the death is 'altruistic': the killing of some cells can benefit the survivors through release of 'public goods'. However, the conditions where bacterial programmed death becomes advantageous have not been unambiguously demonstrated experimentally. Here, we determined such conditions by engineering tunable, stress-induced altruistic death in the bacterium Escherichia coli. Using a mathematical model, we predicted the existence of an optimal programmed death rate that maximizes population growth under stress. We further predicted that altruistic death could generate the 'Eagle effect', a counter-intuitive phenomenon where bacteria appear to grow better when treated with higher antibiotic concentrations. In support of these modeling insights, we experimentally demonstrated both the optimality in programmed death rate and the Eagle effect using our engineered system. Our findings fill a critical conceptual gap in the analysis of the evolution of bacterial programmed death, and have implications for a design of antibiotic treatment.

The inoculum effect and band-pass bacterial response to periodic antibiotic treatment.

The inoculum effect (IE) refers to the decreasing efficacy of an antibiotic with increasing bacterial density. It represents a unique strategy of antibiotic tolerance and it can complicate design of effective antibiotic treatment of bacterial infections. To gain insight into this phenomenon, we have analyzed responses of a lab strain of Escherichia coli to antibiotics that target the ribosome. We show that the IE can be explained by bistable inhibition of bacterial growth. A critical requirement for this bistability is sufficiently fast degradation of ribosomes, which can result from antibiotic-induced heat-shock response. Furthermore, antibiotics that elicit the IE can lead to 'band-pass' response of bacterial growth to periodic antibiotic treatment: the treatment efficacy drastically diminishes at intermediate frequencies of treatment. Our proposed mechanism for the IE may be generally applicable to other bacterial species treated with antibiotics targeting the ribosomes.

From bit level systolic arrays to HDTV processor chips

The initial part of this paper reviews the early challenges (c 1980) in achieving real-time silicon implementations of DSP computations. In particular, it discusses research on application specific architectures, including bit level systolic circuits that led to important advances in achieving the DSP performance levels then required. These were many orders of magnitude greater than those achievable using programmable (including early DSP) processors, and were demonstrated through the design of commercial digital correlator and digital filter chips. As is discussed, an important challenge was the application of these concepts to recursive computations as occur, for example, in Infinite Impulse Response (IIR) filters. An important breakthrough was to show how fine grained pipelining can be used if arithmetic is performed most significant bit (msb) first. This can be achieved using redundant number systems, including carry-save arithmetic. This research and its practical benefits were again demonstrated through a number of novel IIR filter chip designs which at the time, exhibited performance much greater than previous solutions. The architectural insights gained coupled with the regular nature of many DSP and video processing computations also provided the foundation for new methods for the rapid design and synthesis of complex DSP System-on-Chip (SoC), Intellectual Property (IP) cores. This included the creation of a wide portfolio of commercial SoC video compression cores (MPEG2, MPEG4, H.264) for very high performance applications ranging from cell phones to High Definition TV (HDTV). The work provided the foundation for systematic methodologies, tools and design flows including high-level design optimizations based on "algorithmic engineering" and also led to the creation of the Abhainn tool environment for the design of complex heterogeneous DSP platforms comprising processors and multiple FPGAs. The paper concludes with a discussion of the problems faced by designers in developing complex DSP systems using current SoC technology. © 2007 Springer Science+Business Media, LLC.

High performance VLSI architecture for Wave Digital Filtering

The application of fine grain pipelining techniques in the design of high performance Wave Digital Filters (WDFs) is described. It is shown that significant increases in the sampling rate of bit parallel circuits can be achieved using most significant bit (msb) first arithmetic. A novel VLSI architecture for implementing two-port adaptor circuits is described which embodies these ideas. The circuit in question is highly regular, uses msb first arithmetic and is implemented using simple carry-save adders. © 1992 Kluwer Academic Publishers.

Optimized bit level architectures for IIR filtering

Optimized circuits for implementing high-performance bit-parallel IIR filters are presented. Circuits constructed mainly from simple carry save adders and based on most-significant-bit (MSB) first arithmetic are described. Two methods resulting in systems which are 100% efficient in that they are capable of sampling data every cycle are presented. In the first approach the basic circuit is modified so that the level of pipelining used is compatible with the small, but fixed, latency associated with the computation in question. This is achieved through insertion of pipeline delays (half latches) on every second row of cells. This produces an area-efficient solution in which the throughput rate is determined by a critical path of 76 gate delays. A second approach combines the MSB first arithmetic methods with the scattered look-ahead methods. Important design issues are addressed, including wordlength truncation, overflow detection, and saturation.

Systolic two-port adaptor for high performance wave digital filtering

The authors present a VLSI circuit for implementing wave digital filter (WDF) two-port adaptors. Considerable speedups over conventional designs have been obtained using fine grained pipelining. This has been achieved through the use of most significant bit (MSB) first carry-save arithmetic, which allows systems to be designed in which latency L is small and independent of either coefficient or input data wordlength. L is determined by the online delay associated with the computation required at each node in the circuit (in this case a multiply/add plus two separate additions). This in turn means that pipelining can be used to considerably enhance the sampling rate of a recursive digital filter. The level of pipelining which will offer enhancement is determined by L and is fine-grained rather than bit level. In the case of the circuit considered, L = 3. For this reason pipeline delays (half latches) have been introduced between every two rows of cells to produce a system with a once every cycle sample rate.