I'd like to reproduce a couple of small excerpts from a chapter written by Barrie Gilbert in 'Analogue IC design: the current-mode approach' (edited by C. Toumazou, F.J.Lidgey, & D.G. Haigh). In paragraph 2.2., he writes 'At the outset, however, it must be stated that the term "current mode circuit" has no rigorous meaning. The behaviour of electrical networks is always the result of an interplay between voltage and current.'. In paragraph 2.2.1, he writes 'While we have stressed the importance of considering both the current and voltage levels in an optimal view of BJT circuits, there nevertheless exists an extensive class of BJT circuits whose function depends primarily on the use of CURRENTS as signals or functional variables, and which can be designed and understood, certainly at a basic level, using methods in which VOLTAGES ARE NOT CONSIDERED AT ALL. It is circuits of this sort that are often meant by the use of the term "current mode" '. From these excerpts, I would draw out the following interesting features: 1) Barrie Gilbert's use of the phrase 'an interplay between voltage and current'. Here, he avoids attributing roles of cause and effect to either voltage or current; he merely emphasises RELATIONSHIP between the two. 2) Barrie Gilbert writes of a 'class of BJT circuits whose function depends primarily on the use of currents as signals or functional variables'. To me, the word 'use' is key here: it corresponds with an engineer's decision or intention regarding the physical carrier of his signal. He could choose to use either voltage or current as the 'analogue' of the variable to be processed (or indeed both - for example in a transimpedance amplifier, the analogue at the input is current, at the output is voltage). 3) With regard to the design and understanding of current-mode circuits, Barrie Gilbert points to 'methods in which VOLTAGES ARE NOT CONSIDERED AT ALL'. This does not mean that voltages do not exist, or are not essential to the function of the circuit, but simply that in certain circumstances (particularly those circumstances arising in analogue IC design, where one can rely on temperature and process matching), one can find the transfer function without explicitly introducing voltage variables into the analysis. The voltages exist and are an essential part of the circuit action, even though the circuit is "current-mode"; but for the purpose of finding the transfer function, one does not need to know their magnitudes. Further, regarding the choice of current or voltage as the analogue of the signal, I believe it has largely been a pragmatic choice. I think Patrick Bisson's information on early telegraphy systems is illuminating. Another reason for the prevalence of voltage-mode circuits could be this: it is easier to measure the voltage between circuit nodes than to measure current in a conductor. For the latter measurement, one has to open the circuit to insert an ammeter, which is simply not so convenient to do....

Johann: "Why, the hell, we have no artificial intelligence in our house now?" Because of: 1. The inability to identify the central information process (induction, pattern recognition). Within the PR/machine learning field: 2. The inability to give up the conventional formal machinery, especially probabilistic framework. 3. This is a radical step in the history of science. To seek a fundamentally new---non-numeric, or structural---form of data representation that is supposed to reveal completely new side of reality (of objects).

The sludge generation can be calculated by determining total solid production in waste water treatment plant (Secondary treatment). you may find the detail in the link below or consult book by Matt calf & Eddy (4th Edition) or Eckenfelder. http://www.lenntech.com/wwtp/calculate-daily-sludge-production.htm

Dear All, Thank you very much for your valued comments / suggestions,. Before talking about complex waste water streams (especially Industrial), a survey may be carried out to highlight those industries having very simple stream of waste water or an other way is to separate the waste water stream. But actual problem we faced in Pakistan that Industrialist do not want any kind of treatment as they think a WWTP is waste of money....

There are some very interesting points made so far; firstly that the students are more likely to participate if it is in their self interests. Open questions that require discussion instead of an answer will assist in promoting participation but how the students gain from posting a response is still relies on the teacher providing some external motivation. secondly Andres mentions "controversy" and this is a good point because if there are a number of opposing beliefs about a topic there will tend to be more participation. This will increase further if the beliefs are very strong held by both sides, Unfortunately this can be restricted by the course materials that need to be taught at a particular point in the course. The benefits of English being the Lingua Franca and being taught in place of native languages may be more interesting and controversial than the benefits teaching morphemes to L2 students. Should the students be punished for not participating? I have used the carrot and the stick method of increasing participation but have seen that on occasion students will post bland declarative statements just to fulfil the requirements of the grading system and have not engaged with the topic. In the UK a popular buzz word is "Lifelong learning" the idea being that we should encourage students to learn for the pleasure of learning even after they leave formal education. Extrinsic motivation from grades should be replaced by intrinsic motivation from the satisfaction of knowledge. My own interest is in the level of interaction generated by a discussion and this is the focus of my question.

Thanks a lot Geir for your poster reply .I will be very pleased to have this article. I have one about Infantile zinc deficiency: Association with autism spectrum disorders. I will compare both. I am working on evaluation of health hazards lead water hardness in my country. I've known those ions: calcium, magnesium, iron, zinc,..., manganese contribute to water hardness. I am looking for their effect on human body particularly calcium and magnesium. If you have information or documents about my search can you share it with me please? Please receive this paper about Infantile zinc deficiency: Association with autism spectrum disorders.

Thanks for your respond. Is ELISA the only option? How about using SDS-PAGE?

Thanks a lot Kaveh. I am working on evaluation of health hazards lead to the water hardness. Do you have some documentations about my search please?

Please may we have languages with fewer features. The current ones with attendant libraries that do everything are turning us all into "configurators" rather than programmers. Simple is best. Bring back the joy in writing code. PS could we have a ban on any new languages? They are not needed. Besides I have only just got to grips with the ones that I regularly use! (ancient developer)

Well, in the movies there are always great solutions to motivate students... In the 1995 movie "Dangerous minds" Michelle Pfeiffer plays the teacher that starts by scratching the blackboard with her fingernails, then announces she's has a black belt in karate, later on she offers candy bars to enhance students' participation and finally she creates a contest with an exceptionally good prize: having dinner in a fancy restaurant. In fact most of the movies of the kind present suggestions to deal with high school or junior school students, but to deal with undermotivated college students is different. Along this discussion a number of good suggestions were made (Vivian Panes, Abd-elsattar Kaadan, Valentina Haas, Jose Lobo - both extended comments, and of course Michael Reeves). I also think that Dale Pietrzak made a good point: different cultures and students may require different strategies; also did Anthony Fung stating that we should understand the type of learners in front of us and what they know; and even if it sounds unpopular, Kathleen Fahy, also made a good point: assessment usually helps in motivating action by the students (though I 'm not sure that this strategy alone improves learning motivation). I would only add two notes: besides knowing students' motivations (in terms of professional career and interests, rather than hobbies) I would suggest knowing students' expectations about the course in question. After that, try to create an understanding, a compromise, coping students' expectations and your own expectations and plans as a teacher. Also, try to know and understand the reasons why they don't pay attention. If it has to do with physical conditions of the classroom (e.g. poor sound) probably it can be fixed; if it has to do with teaching strategies, try to change based upon the many good suggestions above; if it has to do with student's personal issues try to adopt with them the idea that the classroom is a neutral space where personal problems can't exist. This latter is the strategy used by the french teacher and writer Daniel Pennac, which he describes in his memories of the school entitled "Chagrin d'école" (french title). Good luck. Ana Teodoro

Why do people think that developers aren't already excellent researchers? The more you develop the more you have to extemporize. Then you refine your approach and become more efficient. Then some pundit (often with less experience) tells you to do it another way - frequently you are compelled by management to do it that other way and its no better than what you knew in the first place - you then run out of time ...and leaves you feeling a lot less charitable about researchers. If you can prove your solution before selling it then we'll buy it. Incidentally domain knowledge is often more significant than computing knowledge - I spend more time researching the domain for a job than researching software techniques - to do otherwise would lose me my job. (I am a developer and a researcher)

Hi Wifried, from you... " I think, there exists two independent data processing etc" There are two independent mechanisms. The look-up mechanism that simply responds rapidly to inputs in an appropriate way. This is an autonomic type of systems that is using what might be called "knowledge" . The other systems is goal-based mechanism capable of internalised feedback. This refines (to yield "knowledge") what might be called belief or even: solves open-loop control problems by modelling. We call this thought . It is that process that needs to converge and the emotions system could be seen as part of the system's test for convergence. The emotions system must be a component of evolutionary development so it somehow keeps us viable. Thus when we are not able to respond directly using knowledge we are still able to plan/model and derive viable responses - belief refinement using internal feelings to plan responses that are viable... perhaps emotions are generic tests for what is best for us..? The brain has no obvious data storage and I would suggest that memory is more akin to state-based recall - like a delay line. the states can be triggered and that creates apparent memory. Thus I do not see the brain as a data processing system but instead as a vast state-machine and the feelings (emotions) can be interpreted as states - highly generic expressions of viability that can be triggered whenever we model/plan/think. (The emotions system and the goal system are strongly related and both can be interpreted as generic actions - that also fits in with the concept of a state machine.)

Hi Mr. Masood Sir, Could you please tell me how to use CygWin software to download images from DDSM database o n windows 7, i have install it but it give error.

HI Bridget. Thanks for that. Yes, I have read that article and while its terms are similar the context is different. "passive mechanisms" in nest thermoregulation refer to things such as nest site choice to capture environmental heat, nest modifications to reduce heat loss and supplement brood warmth. My question was more to do with the heat produced by the colony's brood and massed workers, without them actually "actively" increasing the heat production by such behaviour as shivering or wing muscle vibration. I think i have managed to sort out the problem and am hoping to resubmit the MS soon. Just waiting on some statistical support...

@Cyril. I forgot to answer the part of your question that asks '"is it an active or passive device." We call it an active device, simply because it's operation exploits an external energy source. Roughly speaking, any device that has a semiconductor in it is going to be an active device.

Have a look in the pages 201-210 of Kabata-Pendias 2011 (attached): There you can see the form of Mn in soil, the absorption and transport by plants, and biochemical functions.

I think it is better to use a standard Linux distribution and add the resources you need for your work.

I will agree with the previous posters, but I will also point out that Open Access publishers often waive publication charges if there is a justification. Being a young researcher or lack of funds could be accepted as a reasonable justification. It's certainly worth asking the editors for a waiver in both PubMed (eg for BMC Bioniformatics) and PLOS (eg PLOS One, or PLOS Computational Biology), or other journals that have publication charges.