Automated High Throughput Screening of Fluorescent Imaging Plate Reader (FLIPR) Assays Using Assay Platform™ Integrated with Activity Base for ‘on the fly’ Compound Reconfirmation

Advances in the field of automation have meant hitherto complex manual cell-based assays can now be automated. These improvements have brought significant enhancements in throughput, data fidelity and consistency, and allowed a reallocation of constrained resources.Building upon these improvements, we have linked our automated cell-based screening system, Assay Platform™, to Activity Base (IDBS), a software package designed to automate the analysis of HTS data. Customisation of this package has resulted in software that can identify ‘active’ compounds and re-pick them ‘on the fly’ from the original compound plates for triplicate re-testing without operator intervention.Based on an operator initially defining ‘normal’ parameters for assay activity in Activity Base, combined with an automated quality control software module that checks data fidelity, wells containing ‘active’ compounds can be re-picked and re-tested at the end of an automated screening run. Automating cell-based assays has significantly improved productivity, and, with the synergism of Activity Base, has given us greater power to complete each screening run and report ‘active’ compounds to Chemistry more rapidly. This article presents our approach to the automation of cell-based Fluorescent Imaging Plate Reader (FLIPR) screening together with automated active re-test confirmation using Activity Base.     

Information-theoretic framework for unsupervised activity classification

This article presents a mathematical framework based on information theory to compare multivariate sensory streams. Central to this approach is the notion of configuration: a set of distances between information sources, statistically evaluated for a given time span. As information distances capture simultaneously effects of physical closeness, intermodality, functional relationship and external couplings, a configuration can be interpreted as a signature for specific patterns of activity. This provides ways for comparing activity sequences by viewing them as points in an activity space. Results of experiments with an autonomous robot illustrate how this framework can be used to perform unsupervised activity classification.     

Comparative study of antimicrobial and photocatalytic activity in titania encapsulated composite nanoparticles with different dopants

Abstract

The present study describes a relative comparison of antimicrobial and photocatalytic activity in titania encapsulated nickel ferrite nanoparticles with different dopants. The photocatalytic and antimicrobial activity in doped titania composite nanoparticles follows the sequence: W⁴⁺ doped > Nd³⁺ doped > Zn²⁺ doped > undoped titania. The maximum enhancement in tungsten doped titania is attributed to the greater inhibition of electron hole recombination process and decrease in band gap in titania. The ferrite magnetic nanoparticles encapsulated with the photocatalytic shell retain superparamagnetic characteristics and magnetic strength encouraging their potential application as removable antimicrobial photocatalytic composite nanoparticles. The combination of reverse micelle and hydrolysis method is recognised as a promising method for the synthesis of these composite nanoparticles.     

覆膜条件下氮磷肥对土壤理化性质、酶活性及烟草生长的影响

通过大田试验研究了覆膜条件下氮磷肥料互作对植烟土壤理化性质,土壤酶活性以及烟草生长的影响。结果表明,覆膜能提高植烟土壤温度及中性磷酸酶的活性,促进烟株对氮、磷的吸收;明显地促进烟株地上部的生长,使烟株早发育。但覆膜导致烟株的根冠比下降,且覆膜后土壤的氧化还原电位和pH值下降,可能造成土壤中硝化作用的减弱,使NH 4-N向NO-3-N转化减慢,从而降低了烟草对NO-3-N的吸收率。覆膜条件下土壤中脲酶的活性随尿素、磷肥用量的增加而有所降低,且覆膜本身也降低了脲酶的活性。     

Superplasticity and deformation mechanisms in NiAl(- Mo) alloy

Abstract

The mechanical behaviour and microstructural evolution in tension of NiAl - 9Mo eutectic alloy at 1100 ° C and strain rates from 10^-5 to 10^-3 s^-1 have been investigated. High values of strain rate sensitivity index, but relatively small elongations between 150 and 200%, have been observed. Tensile specimens with various strains were quenched in water to preserve the dislocation structures for TEM examination. The TEM results show that the dislocation configuration and density change significantly with an increase in strain rate, and therefore correspond to different deformation mechanisms. At a low strain rate (5.5 × 10^-5 s^-1), the dislocation density is relatively low and dislocation activity is regarded as an accommodation mechanism for grain boundary sliding. In contrast, the high density of dislocations as well as clear subboundaries observed in grains at a high strain rate (5.5 × 10^-4 s^-1) suggest that the dislocations are active directly in response to the applied stress as well as participating in the relaxation process of grain boundary sliding by subboundary formation. Thus, grain boundary sliding is mainly responsible for superplastic deformation at a low strain rate, while superlastic deformation at a high strain rate is controlled by the combined operation of both grain boundary sliding and dynamic recovery.     

Sulphur partition between hot metal and high alumina blast furnace slag

Abstract

The sulphur partition ratio between hot metal and high alumina blast furnace slag (>18% alumina) has been examined on cast by cast basis for G blast furnace of Tata Steel. Equilibrium sulphur partition ratio was calculated from sulphide capacity with the help of oxygen activity in the melt. Oxygen activity was calculated from SiO₂/Si, MnO/Mn and CO/C equilibria. The equilibrium sulphur distribution calculated by considering the reaction [C]+[O]=(CO)_g in equilibrium for estimation of oxygen activity was very close to measured sulphur distribution ratio on cast by cast basis. Use of MnO/Mn pairs gives very high oxygen activity compared with SiO₂/Si and CO/C pairs.     

Electrocatalytic properties of electrodeposited Ni–Mn–S system in alkaline electrolytes

Abstract

Ni–Mn–S was electrodeposited on mild steel from sulphate–thiocyanate baths. The resultant materials were evaluated for electrocatalytic activity towards hydrogen evolution reaction in 30 wt-% KOH. Incorporation of sulphur in Ni–Mn improves the electrocatalytic activity giving a sizeable increase in exchange current density j ₀. In Ni–Mn the hydrogen evolution reaction is through a Volmer–Tafel mechanism whereas in the Ni–Mn–S system follows a Tafel mechanism. The influence of deposition current density (CD) was investigated. Electrocatalytic activity increased with increase in the deposition CD and was maximum in samples deposited at 80 mA cm^?2.     

Action and interaction in volunteered geographic information: a workshop review

This paper presents a summary of the Action and Interaction in Volunteered Geographic Information international workshop which was held as a one day pre-conference workshop to the 16th Annual Association of Geographic Information Laboratories in Europe conference in Leuven, Belgium in May 2013. This paper summarises the important outcomes of workshop presentations and key discussion statements from participant contributions to an open-floor discussion on the most pertinent issues in Volunteered Geographic Information (VGI) research. Participants engaged this discussion focused on what are the most likely problems which could form the basis for a research agenda in VGI composed of both short- and long-term research objectives. While the development of a VGI research agenda will require the involvement of the broadest possible spectrum of disciplines, this paper is, none-the-less, an important first step on this journey.     

Performance of a Dynamic TDMA System for Mobile Wireless Access

A dynamic TDMA system can utilize voice activityand allow the integration of voice and data traffic.This can be achieved by allocating frequency channelsand time slots on demand. In this approach, upon the arrival of a talkspurt or a data packet,the base station is requested to assign a time slot foreach transmission. Message requests and assignments ofmobile users are carried over a Control channel, while the voice and traffic are transmittedover a Traffic channel. Time slot assignments are madefrom a pool of Traffic channels. A numberof slots in the pool will be shared by voice and data, with voice having priority over data, andthe remaining will be used by data only. Voice slots arereserved for the duration of the talkspurt whereas datapackets are assigned on a per-slot basis. Data packets can be buffered whereas voicetraffic can only tolerate limited delay beyond whichtalkspurts will be clipped off. The Control channeluplink access is based on Slotted Aloha so that mobile users have autonomous access to base stations.This paper presents the performance of the dynamic TDMAsystem outlined here. The analysis aims at assessing thecapacity gained by using voice activity and voice/data integration, in terms of theimpairments introduced to voice quality (e.g., speechclipping and/or delay) and the delays to data packets.The analysis has been based on a discrete time Markov model operating on a frame-by-frame basis thatprovides the joint distribution of the number of activevoice and data users in the system. The analysis alsoevaluates the delays of message requests via the uplink control channel. In evaluating theclipping probability, we combine the impact of both theaccess delays at the control channel as well as theunavailability of time slots in the pool. Performance results indicate that the capacity gain mayexceed 80% and the speech clipping can be kept below 1%.Also, data packets may be transmitted with limiteddelays even when all capacity is allocated for voice users. The proposed approach may be used toenhance the capacity of the existing TDMA cellularsystems and to provide integration of voice and dataservices.     

Primitive-Based Action Representation and Recognition

In robotics, there has been a growing interest in expressing actions as a combination of meaningful subparts commonly called motion primitives. Primitives are analogous to words in a language. Similar to words put together according to the rules of language in a sentence, primitives arranged with certain rules make an action. In this paper we investigate modeling and recognition of arm manipulation actions at different levels of complexity using primitives. Primitives are detected automatically in a sequential manner. Here, we assume no prior knowledge on primitives, but look for correlating segments across various sequences. All actions are then modeled within a single hidden Markov models whose structure is learned incrementally as new data is observed. We also generate an action grammar based on these primitives and thus link signals to symbols.