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  • Myroslav Kozak added an answer in Refractive Index:
    Сan I use the Kramers Kronig relations for a nematic liquid crystal?


    Can I calculate the dispersion of nematic LC's refractive index if I have absorption spectrum in visible and UF region by Kramers-Kronig relation. How can I do it if it's possible?

    Thank you!)

    Myroslav Kozak · Uzhhorod National University

    And what is your goal? My opinion, the Kramers-Kronig relations have quite a contentious issue even for the canonical semiconductor such as silicon. Usually measured dielectric constant in the near infrared region and the visible region of the transition using here these relations СС. However, even on the red line 0.63 micron, and the imaginary part of DC index prelommleniya disputiruetsya. The problem is that the rCC model pretty thing. They are absolutely accurate for non-dissipative srredy where the imaginary part of the DP defines only the loss of the braking of the electron field. If there is absorption, the electron passes from the valence band to the conduction band, the energy of the light is distributed in the heat energy to the lattice vibrations. The law of conservation of energy in the photons, electrons are not stored. I would advise you to apply the technique of reflection, that is, ellipsometry. Russia has produced excellent ellipsometers spectrophotometers.
    I wish you success, Miroslav.

    А какая у Вас цель? Мое мнение, соотношения Крамерса-Кронига есть довольно спорным вопросом даже для канонического полупроводника, например кремния. Обычно измеряют диэлектрическую проницаемость в ближней ИК области, а в видимую область переходят при помощи вот этих соотношений КК. Однако, уже на красной линии 0.63 мкм мнимая часть ДП и показателя преломмления диспутируется. Проблема в том, что сКК довольно модельная вещь. Они абсолютно точны для недиссипативной срреды, где мнимая часть ДП определяет только потери на торможение электрона полем. Если же есть поглощение, электрон переходит из валентной зоны в зону проводимости, энергия из световой распределяется в энергию тепла на колебания решетки. Закон сохранения энергии в системе фотоны-электроны не сохраняется. Я бы вам советовал применять технику отражения, т.е. эллипсометрию. В России выпускаются отличные эллипсометры-спектрофотометры.
    Желаю успехов, Мирослав.

  • Hameed Shah asked a question in Ethyl Acetate:
    What may be the reason that a column separate flavonoid further confirmed by TLC, shows some impurities in 1H-NMR peaks?

    I have confirmed a single spotted compound (having brown colour, so we suggest it may be flavonoid) on TLC, then used column chromatography to separate it, and it was further confirmed by TLC as single spot using acetone:ethyl  acetate(1:2) as solvent system. Now the 1H-NMR is confirming some impurities, as the doublets, triplets etc are not of good standard.

  • Susantha Jayasundara added an answer in Agricultural Systems:
    How soil microorganisms are related with the greenhouse gases (CH4, N2O, CO2) emission under agroecosystems?

    Does detail knowledge of soil microorganism and its management can regulate the emission profile of the agricultural system. How this emission ratio will respond to the changing climate in future.

    Susantha Jayasundara · University of Guelph

    Dear Rama,

    Of the three greenhouse gases (CO2, CH4, and N2O), CO2 is the dominant gas contributing to the total soil GHG profile, followed by N2O.  In most agricultural soils (except flooded rice fields) contribution from CH4 to the total GHG profile is insignificant.  For example, proportional contribution of three gases to total soil GHG in a complete Maize growing season (May to October in Northern USA and Canada) is reported to be about 90% CO2, < 1% CH4 and about 10% N2O (note that CH4 and N2O is expressed in CO2 equivalents using global warming conversion factors of 23 for CH4 and 296 for N2O).

    However, we need to remember that almost all of this CO2 may be recently fixed C by photosynthesis in corn (originating from crop residue decomposition and root respiration).  Therefore, for a meaningful assessment of the net global warming potential of this cropping system, changes in soil C need to be examined over several years.

    Regarding the second part of your question: photosynthetic bacteria can capture CO2 from the atmosphere directly, but their contribution to C balance in crop lands is minor compared with photosynthetic C fixed by crops.  Some examples of potential industrial applications of photosynthetic bacteria can be seen in the links below:



    Best regards.


  • Paul C. Lyons asked a question in Field Works:
    In field work what is the best way to determine yoour map location?

    Map location is a critical part of doing geological field work.

  • Wasana Madushanka Ediri Arachchi asked a question in Testing:
    Can obtain electronic readings for x-ray field congruence?

    Normally the field congruence test is carried out by conventional test tool which require more interventions for manual readings...

  • Ghulam Mustafa asked a question in PEAKS:
    How i calculate Peak Discharge, Hydrograph Volume and Duration from daily discharge data?

    Respected Friends

    Help me to find out these variables from daily discharge data.....

  • Alex Ignatov added an answer in Barley:
    Can we determine the resting spore population of Polymyxa graminis in plant roots by taking optical density?

    I want to determine the resting spore population present in Barley roots. if anybody can suggest how a single resting spore of Polymyxa graminis looks like, while resting spore suspension prepared by crushing the roots.

    Alex Ignatov · Russian Academy of Sciences

    There are many methods for Polymyxa graminis detection in plant roots, but you hardly will find large number of spores sufficient for evaluation by optical density. It is easier to stain them or link to specific antibodies and count by number.




  • Soumendra Saha added an answer in Cricket:
    Can anyone give links of research on "rise of national cricket team" or cricket related topics?

    I want to do a research on Bangladesh National Cricket team for my masters degree. 

    Soumendra Saha · Universiti Sains Malaysia, Kota Bharu, Kelantan, Malaysia

    Hi Shakib, You look like Shakib-Ul-Hasan though, but you are not the Legendary Cricketer, rather you are interested in Cricket research. Shakib and lot of others in Bangladesh National Team are closely known to us (myself and Dr. Srilekha Saha), since we took care of lots of them (Mushy; Razzak; Shubho; Naim; Naszmul...and so on) while they were training in BKSP, and obviously lot others while we were tasking care of them starting July 2010, before they handled a 4 - 0 victory over New Zealand and thereafter 3 - 1 to Zimbabwe....until their 2011 WORLD CUP performance. We can talk all about it in length (if you want to keep in touch), but before that you can find out our cricket researches with those boys. Take care and have nice Cricketing times  

  • Sanjay Rode added an answer in Economics:
    Do you have any good recent paper about Wagner's Law?

    I looking for recent works about the relationship between public spending and production in an economy. The idea is test the validity of Wagner's law. 

    Sanjay Rode · Somaiya Vidyavihar

    It is absolutely  a good research paper. Do you have any research paper related to India. I would like to see it for reference.

  • Harekrishna Misra added an answer in Agricultural Extension:
    What are the steps in analysing agricultural extension policy or any development policy?

    I am coming up with a module for teaching post graduate students on policy analysis related to agricultural extension or rural development.  What I find in literature is mostly about agricultural policy or food policy analysis using economic models.  Is there a framework that does not use these economic models?

    Harekrishna Misra · Institute of Rural Management Anand

    I agree, though not in its entirety, that economic dimensions are essential. One has to be careful, as to whose context we bring in!, is it for the intervening agencies or the farmers! I think bringing both to the context would be beneficial, since they are all supposed to be in supply chain. Not exactly in a extension!

  • Muhammad Rafique added an answer in Absorptive Capacity:
    What dimensions of Quality of workplace Life (QWL) directly impact Absorptive Capacity (Knowledge Acquisition and Assimilation)?

    what dimensions/ indicators of Quality of Workplace Life (QWL)  directly or indirectly impact two components of Absorptive capacity ( Knowledge acquisition and assimilation ) in context to work shop floor employees? Generally employees were observed as  least interested in gaining new knowledge.

    Absorptive capacity is the ability of organization to acquire, assimilate and use new knowledge in its processes.

    Thanks in advance

    Muhammad Rafique · NUST College of Electrical & Mechanical Engineering

     Dear Michael,

    Thanks for this valued input. 



  • Veena Vidyasagar asked a question in Abortion:
    Cases of medical abortion are usually followed up by USG to determine completeness of abortion. At what maximum ET it is assumed to be complete?

    At what endometrial thickness one should straightaway go in for evacuation? At what thickness one can wait and watch? Should one pay more importance to clinical presentation. What should be protocol in an asymptomatic woman following medical abortion? In India, cost factor also has to be taken into consideration.

  • David Bruce Conn added an answer in Dung Beetles:
    Has anyone characterized cooperative behavior in dung beetles?

    A couple of day ago I was driving on a dirt road near Albany, Texas when I came across ~50 dung beetles working together to carry a mouse across the road. I didn't have the idea to take a video unfortunately but I did snap a quick picture. Any insight into this would be great. 

    Photo attached 

    David Bruce Conn · Berry College

    A couple other thoughts.  Are you sure they are dung beetles?  I can't tell for sure from the photo.  I also wonder if all are the same species.  I notice flies are also present.  Were they truly cooperating or just scrambling for their share of the carcass, so that the whole mass moved?

  • Dr.Umar Fauzan added an answer in Language Teaching:
    Research about the effect of feedback in supporting learning by teaching?
    I want research about the effect of feedback in supporting learning by teaching in a teachable agent environment: This question suggests that learning benefits occur from preparing to teach. Its not clear what other hypothesis and aspect of learning helps to increase outcome to learning process?
    Dr.Umar Fauzan · institute for Islamic studies Samarinda, Indonesia

    Hi Rasthi,

    You might read a dissertation of Jeremie Seror (2008) entitled "Socialization in the margin: second language writer and feedback practice in university content course"

  • Lynn Shepler added an answer in Bacillary Angiomatosis:
    What investigations would you suggest to confirm a suspected case of cat Scratch disease (bacillary angiomatosis)?

    Cat scratch disease is a zoonotic febrile illness spread from a cat’s oral and pharyngeal flora by a scratch to humans, particularly to children. The disease is characterised by regional lymphadenopathy, fever and other systemic symptoms. A skin papule may be present at the inoculation site. The most common causative species of cat scratch fever is considered to be Bartonella henselae. Also called bacillary angiomatosis, cat scratch disease is associated with bacteraemia and endocarditis and may require prolonged therapy. What are the best investigations to confirm the diagnosis of a suspected case of cat scratch disease? angiomatosis)?

    Many thanks in anticipation.

    Beat reagards

    Dr Sayed S Bukhari MD, FRCPath

    Consultant in Infection



    Lynn Shepler · University of Chicago

    Dr. Buktari,

    As you know, cat scratch fever may present in humans in subtle ways, or not so subtle. In terms of laboratory investigations, I know that Galaxy Laboratories in North Carolina, founded by Ed Breitwschwerdt, DVM is considered to have cutting edge technology in conducting laboratory testing for Bartonella. Reportedly they have developed a genus PCR that can be used on blood or serum, and may also be used to identify Bartonella in tissue slides. They also have a new method of doing blood cultures for Bartonella based on a specially designed medium BAPGM. Thy keep cultures for up to eight weeks. Breitschwerdt also does more esoteric tests in his private research lab --- but he developed Galaxy for commercial use because his research lab was being inundated with testing requests. Note that there can be strain differences in test construction, so it is possible to test positive on one IFA, and negative on another. It is an organism that does not stay in the bloodstream very long, or it can be present intermittently. I would do multiple sets of blood cultures and PCRs, and also the IFA. Some patients will test negative on everything because of the immune suppression the organism is known to cause, Although not presently noted in the literature, many patients with Bartonella will experience a Jarisch-Herxheimer reaction when administered appropriate antibiotics. Hope this is helpful. If you have further questions, you might consider sending an email to Galaxy  --- contact@galaxydx.com. I have no commercial or management ties to this lab, but admire their work. For some people, it is a chronic relapsing disease that they can't clear despite antibiotics.

  • Uğur Canpolat asked a question in SEC:
    Where does the limit of 30 sec for the diagnosis of AF episode come from?

    What about patients with less than 30 seconds episodes of AF?

    A therapeutic difference is a should, may or must?

  • N. Sudarsono added an answer in RNA-Seq:
    What is the RNA type when I use CaMV 35S promoter to express a RNA sequence in vivo?

    I want to express a RNA sequence in plant cells, but i don't know what  type the RNA is when I use CaMV 35 promoter. Is it a mRNA type with a 5' cap and poly A or a ribosome type without 5'cap and poly A?

    N. Sudarsono · Bogor Agricultural University

    If you drive the expression of certain coding sequences with the CaMV promoter, the transcript will be the mRNA type. Under in vivo conditions, regular RNA processing steps will happen to those transcripts, such as there will be : (1) capping at the 5' end of transcripts; (2) Intron splicing (if any) and exon joining, (3) trimming at the 3' end and addition of poly-A tail.

    Good luck ...

  • Santosh Bhardwaj added an answer in Chromatography:
    Mass spectral interpretation
    Dear all,

    I would like to know the best book for interpretation of mass spectra, if any of u can sugeest then kindly suggest me atsbhardwaj81@yahoo.com
    Santosh Bhardwaj · Shimadzu Analytical India Pvt Ltd

    Thanks you both of you.....i am studying same book for interpretation of mass spectrum included in my research studies !!!

  • Sungkun Hwang asked a question in Feature Selection:
    What should I use either feature extraction or feature selection?

    Hi, I want to use either feature extraction or feature selection for a high dimensional data set (1000 by 100 matrix). If I have to use only one between both methods, what should I choose? Is there any criterion for deciding on feature extraction or feature selection?

  • Soumendra Saha added an answer in Research Publications:
    What is the difference between universal impact factor, global impact factor and impact factor?
    Some journals have global impact factor some have universal impact factor and some have only impact factors. I am totally confused, which one is acceptable? Most of our teachers and supervisor always blame the journals which have GIF or UIF. I am not understanding this phenomenon. If we publish a paper in that journal which have GIF or UIF will that publication have value?
    Soumendra Saha · Universiti Sains Malaysia, Kota Bharu, Kelantan, Malaysia

    Hi Everyone, It is more important to find out one journal that is Authentic, that means it is indexed ....either in ISI, or SCOPUS or PubMed ...and so on. Some of the researchers are considering some indexing systems as predatory...while truly enough JCR also takes care of the evaluation privately. InnoSpace SJIF would be another evaluation criterion, that takes care of the evaluation fairly enough. Scientific Domain International is coming out very fast, and they take care of their activities openly.....that gives more impetus, since that enriches authenticity. We'll keep on talking a lot about this never ending issues....let's focus onto work more.....following ethically sound and rigorous RCT methodology....and to disseminate the findings in preferably authentic platforms

  • Nader Aghakhani added an answer in Music Therapy:
    Is music therapy useful for every patients and all of diseases?

    Music Therapy is the clinical and evidence-based use of music interventions to accomplish individualized goals within a therapeutic relationship by a credentialed professional who has completed an approved music therapy program. Is it useful for every patients and all of diseases? How?

    Nader Aghakhani · Urmia University of Medical Sciences

    Dear Dr.Rayan.

    Do you have any experience about the effects of holy Qoran on the patients?

  • Natalia Kovalchuk added an answer in Biomass Conversion:
    Does anyone have Volume to Biomass conversion factors for Cladoceras groups?

    I'm searching for conversion factors to estimate carbon biomass of cladocera group (Mesozooplankton) from its measured biovolumes. I found many articles about the length - weight relationships, but not volume to mass. If anyone knows the factor values or related articles, please suggest me. Thanks.

    Natalia Kovalchuk · Uzhhorod National University

    In determining the biomass of small aquatic organisms, we measured and considered individuals in different size groups of each species and then used

    "Nomograms for determining the weight of aquatic organisms by size and form of body "

    L.L.Chislenko, Publishing house: Science. - Leningrad, 1968. – 108 p.

    The tables are for sea mezobenthos and plankton, but in size, top view and cross section, Cladocera biomass can be estimated also.

  • Rajagopal Appavu added an answer in Liposomes:
    Software for drawing the liposome chemical structure?

    I am looking for a software to draw the chemical structure of liposome from lipids to liposome for free. If you have any idea please let me know, i appreciate your help.



    Rajagopal Appavu ·

    Thanks Fernan Diaz..

  • Nader Aghakhani added an answer in Domestic Violence:
    What can a nurse or a physician can do to prevent domestic violence after female patient discharge?

     More than three quarters of domestic violence victims who report the incidents to police seek health care in emergency rooms, but most of them are never identified as being victims of abuse during their hospital visit. What can a nurse or a physician can do to prevent domestic after female patient discharge?

    Nader Aghakhani · Urmia University of Medical Sciences

    Dear Dr. Almeida,

    my mean is prevention.

  • Behzad Shahbazi added an answer in Ball Milling:
    What is the suitable particle size range for a good XRD analysis?

    I am working on rock mineral sample and reduced particle size by ball milling. I wish to know the range of the particle sizes suitable for getting clear XRD results.

    Behzad Shahbazi · Tarbiat Modares University

    pulverizing to -200 mesh is often suitable for mineral characterization.

  • Anshul Faye added an answer in Abaqus:
    Can anyone advice on an Abaqus example problem?


    I am trying to run .inp file and .f file from an example in Abaqus Manual. I have attached link to this question!

    I have made the necessary changes to be made in the .inp file as per the instructions provided. However when I run the two files using abaqus j=exa_hydfracture user=exa_hydfracture , there are several files generated but following error is seen in the text file generated. Please suggest!

    Abaqus JOB exa_hydfractureAbaqus 6.14-2Abaqus License Manager checked out the following licenses:Abaqus/Foundation checked out 3 tokens from Flexnet server license2.arsc.edu..Begin Compiling Abaqus/Standard User Subroutines6/28/2015 11:28:12 AMIntel(R) Visual Fortran Intel(R) 64 Compiler XE for applications running on Intel(R) 64, Version Build 20150407Copyright (C) 1985-2015 Intel Corporation. All rights reserved.

    ifort: NOTE: The evaluation period for this product ends on 27-jul-2015 UTC.End Compiling Abaqus/Standard User SubroutinesBegin Linking Abaqus/Standard User Subroutines Creating library standardU.lib and object standardU.expEnd Linking Abaqus/Standard User Subroutines6/28/2015 11:28:15 AMBegin Analysis Input File Processor6/28/2015 11:28:15 AMRun pre.exe6/28/2015 11:28:25 AM Abaqus Error: Analysis Input File Processor exited with an error.Abaqus/Analysis exited with errors



    Anshul Faye · Indian Institute of Technology Kanpur

    Dear Aditya,

    This file is already modified as per the instructions written after "MAKE CHANGES HERE". You need not to modify anything.



  • Christopher Hartzler added an answer in Aquatic Macroinvertebrates:
    For aquatic macroinvertebrates: should I do individual or sample-based rarefaction?

    I was wondering how others have compiled rarefaction to compare species richness and density between two study areas, specifically how they organized their collection of specimens. Techniques like kick netting and surber samplers can easily collect hundreds of individuals. I've read that when calculating rarefaction, it's best to have 20 or more samples/individuals. Getting 20 individuals in one collection is no problem, of course, but how do you assemble enough samples (for example, dividing an area into quadrats and taking N amount of samples) and still realistically sort/identify them? I've only just begun to calculate rarefaction (using EstimateS), starting with a sample (but individuals based) of macros that had 341 individuals and 24 different taxa identified. I think a sample-based rarefaction would allow for more accuracy in studies, especially since they are known for distribution in micro-habitats that can be overlooked when few sample sites are chosen. Although I hasten to think of identifying 150 samples of 300+ individuals to do so, as I'm often doing this by myself. Perhaps a more samples-based collection method should be developed? By that I mean collection methods that involve more samples that collect fewer individuals than you typically see in a kick-net or surber-sampler method? I haven't come across many studies of macroinvertebrates that calculated species richness/density using samples-based collections. 

    Christopher Hartzler · York College of PA

     Thank you, Declan, for your detailed response. I agree on the separation of samples, especially since my future study may involve using the EPA's bioassessment protocol for multiple habitat types (sampling different microhabitat types within a single study area in proportion to their coverage). In the past, I've been involved in sampling that was primarily 5-6 samples pooled into one, which made for tedious picking through lots of detritus material (I'd rather pick through several smaller samples). And also, I'm focusing on canopy coverage and will use Anne and Andrew Goodenough's program CanopyDigi to take canopy coverage measurements at each kick site, and can later pool both the macro samples and canopy coverage data. I plan on using sites that vary in canopy coverage, though having individual canopy coverage measurements for each kick sample will be useful.

  • Pablo G. Goicoechea added an answer in Genetic Data Mining:
    Is it possible that Nst is smaller than Gst based on the output from the program Permut, and why?

    like this:

    hS (se) 0.610 (0.0663)
    hT (se) 0.845 (0.0289)
    Gst(se) 0.278 (0.0805)

    vS (se) 0.540 (0.0676)
    vT (se) 0.636 (0.0601)
    Nst(se) 0.151 (0.0532)

    Nst was smaller than Gst , it was quite the puzzle for me.

    Thanks in advance.

    Pablo G. Goicoechea · Neiker-Tecnalia Basque Institute for Agricultural Research and Development

    Indeed, Caner is absolutely correct!! But you might wisht to find a biological meaning for such result. The oak example shows how the blending of maternal lineages maintained in different refugia can result in a population structure with Gst>Nst. However, your default hypothesis is that Nst is greater or equal than Gst. Have you thought whether your Gst estimate is significantly greater than your Nst estimate?

    Hope this helps.


  • Raj K Shankar added an answer in Mentor:
    Are there mentoring programs avaialble for young professional researchers?

    As a recent graduate with a passion for research, I am interested in finding either a mentor or mentoring program that supports individuals in my position to hone their skills and better prepare them to be successful in their field. Does anyone know of any programs or have an interest in mentoring?

    Raj K Shankar · Entrepreneurship Development Institute of India

    Dear Eliann,

    I believe all scholars (probably at all stages of their career) would require a mentor. In fact the power of mentoring has been more than adequately highlighted in literature. The latest proponent of this being Dr Marshal Goldsmith. My suggestions come from extensive fieldwork (mentoring/coaching) with entrepreneurs in India. There are two ways I think young scholars can take steps to gain mentoring:

    a) Find and read authors of interest. Explore their work from the view of reflecting deeper on their writings. For example: I am a big fan of Dr Peter Drucker. I use his writings (re reading many of them) to reflect on his approach to gaining insight. Going beyond the subject into the 'thinking' behind the subject. There is a famous story of Ekalavya (in Indian Mythology) a student who was refused discipleship by the greatest teacher of his time. He is said to have made the teacher his mentor by simply keeping a statue of him and practicing. A story worth reflecting on.

    b) Network/Seek individuals who you feel a connect with: Explore the work of specific senior scholars in your own field of research. Attempt reaching out to them with specific requests. I am sure if you reach out to ten, a few would respond and you may find your one mentor. Finding them has to be a careful process as you should ensure there is alignment in philosophy, approaches, beliefs, and values.

    Two books that come to my mind which may be of help to you:

    1. Mastery by Robert Greene

    2. Howard's Gift by Eric Sinoway

    In fact I have come to believe that mentors need not be from your field, they need not be senior to you, they need not be better than you - but they must be people who wish to see you blossom. I truly hope that you find that person soon in your life and blossom too.

    Best wishes


  • Gianrocco Tucci asked a question in Faculty:
    Intellect is able to universalize the singularity of intuition. Then, can there be relations with the Absolute? If any, which one and why?

    Intuition is defined as "the understanding by the mind of reality directly as it is, and not in the form of a perception or concept, nor as an idea or object of reason, all of which are instead learning intelligence".

    Intellect is recognized in the first place among the characteristics of the human being, while the intuition makes his presence felt in the sudden illuminations and insights of truth which are the gift of the greatest thinkers.

    Then, in the 'most general sense, intuition ready and acute is the perception of reality even as a premonition of future events or upcoming. The very ability to understand, especially as habitual disposition: to have, or to have no insight; it is fitted with great vision, a ready intuition.

    In other words, the intuition in philosophy is a way of knowledge or independent learning from experience or reason, generally conceived as innate ability of the intellect. The notion of intuition has taken different meanings, sometimes opposite, and can not be defined except in the context of the work of individual philosophers.

    Intuitive knowledge allows the individual understanding of a unified universe and allows the intellect to be part of the Infinite Being. Intellectual intuition is the organ of all transcendental thought. Indeed, the transcendental thought is striving to present itself, through freedom, as object what otherwise would be no object: it presupposes a faculty that is able to produce and perceive at the same time certain acts of the spirit, so that production and intuition of an object be absolutely one; precisely this faculty is the faculty of intellectual intuition.

    Transcendental philosophy must therefore be constantly accompanied by intellectual intuition: any supposed darkness of that philosophy has its reason not in its incomprehensibility, but in the absence of the organ in which it must be understood. Without this intuition the philosophizing itself has no substrate that can withstand and sustain the thought; is that intuition which in transcendental thinking replaces the objective world and rules the flight of speculation.

    Intuitionism is a philosophical orientation where priority is given to the intuition and spontaneous impressions and to implicit aspects of the reasoning than in the explicit reasoning and to arguments.

    In the intuitionistic logic steps epistemologically inadequate are refused in demonstrations. In classical logic, a statement A means that "A is true". In intuitionism, such a formula is considered true only in the case it is possible to show a demonstration. It is noted that in Plato (as in Parmenides) Being is not something that is derived from the senses, nor is demonstrable by reasoning: it is located above the logical-dialectical path, and is accessible only by intuition.

    Immanuel Kant uses the term apodictic to mean necessary, extending the value of the term not only to what is shown as true but also in what refers to the activity of  intuition from which the required certainty flows.

    For Fichte it was illogical to admit, as Kant did, that intellectual intuition (philosophical tool par excellence with which to be able to deduct being from the idea) had no value.

    The activities of self-consciousness in Kant is ultimately limited in the data offered by the sensitive intuition, without which it is idling, resulting in a knowledge - that produced by the ideas of reason, examined in the third part of the Critique of Pure Reason: transcendental Dialectics - purely illusory.

    Transcendental philosophy is the story of self-consciousness that covers every stage of the process prior to conscience:

    A step in the process is that of productive intuition, the Ego begins its self-construction, perceiving itself as "polarity" with respect to  the '' object ', as sentient that feels, in fact, his " suffering the limit " and is prepared, as an activity, to overcome it (Kantism).

    Conventionalism reiterates that to privilege a geometry or a system of spatial references depends solely on agreements made by the scientific operator on the basis of criteria of opportunity and convenience. It rejects the problem of finding an objective and unique criterion as a false problem related to a way of thinking traditionally and metaphysically.

    Conventionalism serves as a substrate for many and disparate philosophical positions, such as, for example, the pragmatism of F. Schiller or spiritualism of E. Boutroux. It should however be noted that, for what concerns the foundations of mathematics and logic, conventionalism in the early decades of the XX century quickly lost ground in the face of greater wealth and articulation of other currents such as formalism, logicism and intuitionism.

    Therefore, philosophy that was born not as a simple intuition or subjective impression but as a rational deductive discipline which wanted to show with logical arguments what was assumed, is now being questioned by the philosophers themselves with a radical critique of reason: the absolute rationality of idealism is challenged by the same reason.

    The philosophical theme of the Absolute has a limited development but very quick and of exceptional importance in the history of European thought at the turn of the eighteenth and nineteenth centuries. In 1781 is released the first edition of the Critique of Pure Reason by Immanuel Kant. The intention of the philosopher is to enter the debate on science and on the foundations of knowledge, moving the investigation from the scope of the object (for example, nature) to the subject. With his "Copernican Revolution" he tries to establish a difference not more questionable between what is knowable (phenomenon) and what is not (noumenon).

    Kant brings out a second edition, revised and corrected of the Critique, precisely in order to clarify difficulties of interpretation arose around the noumenon and the hypothesis of pure intuition. In 1787 comes out also the Critique of Practical Reason, in which Kant clearly distinguishes practical philosophy from the theoretical one: while the first draws it out of the Absolute, because it obeys only the laws that reason discovers within itself; on the cognitive level the subject is bound by the phenomenal limits, that as having senses, he constructs on the object.

    The absolute spirit in Hegel is the time when the idea comes to full awareness of its infinity, and it is the result of a dialectical process represented by art, religion and philosophy. These activities do not differ because of their content but for the shape. Art knows the Absolute in the sensitive intuition.

    Reality is for Hegel movement, becoming, process, development. It is not static or abstraction but a living subject, real, current, which manifests itself in the world both natural and historical. The reality is the ‘Infinite spirit’, also called ‘Absolute’ or ‘Idea’ or ‘Reason’. For these reasons Hegel defines his philosophy a form of idealism in a double sense: on the one hand because the true reality is precisely the idea, that is, the Thought, the Spirit, the Absolute, the Reason; the other because it affirms the idealism that is not the reality of what we call "finished". For Hegel, in fact, the finite does not exist in itself (otherwise it would be the Absolute) but only in the context of relationships; in other words, if the reality is a unified whole, what exists is a part or event: the finite exists only in the infinite and by virtue of the infinite. His philosophy was defined as a sort of pantheistic monism in the sense that Hegel sees in the world (the finite) the manifestation of (the Infinite). And the Absolute is a spiritual subject in the evolving stage, of which all that exists is a phase or moment of realization.

    In Scholastica it was evident how philosophical knowledge of the Absolute were to pass for an act of faith or through the immediacy of  intuition: knowing means in fact connect, to relate something with other than itself; but since the Absolute has everything inside, it has no term of external reference with which can relate. The five ways proposed by Thomas Aquinas in order to rise to the intelligence of the revealed truths thus allow only coming to an intuitive knowledge of God's existence, without claiming to prove logically. They will instead be confused, in the era of the Enlightenment, with the ability to "prove" with reason the fundamentals of faith.