Latest Contributions

Jun 232012
 

Fabian Bross and Philip Pfaller

Ludwig Maximilian-University, Munich, Germany

Journal of Unsolved Questions, 2, 2, Articles 19-24, 2012 (Received Feb 14th, accepted June 20th 2012, published online June 22nd, 2012)

The goal of this study was to test a weak form of the Sapir-Whorf Hypothesis dealing with one of the biggest unsolved questions in linguistics: Does language affect the way we think? Grammatical systems in the world’s languages differ in many aspects. Unlike English or German many languages group nouns on the basis of noun classifiers. Recently research has adressed the question if these linguistic categories built up by classifier systems influence non-linguistic thought. In this paper we studied Mandarin Chinese and Thai—two languages with classifier systems. Although both are classifier languages they categorize objects in different ways. We tested if these system differences lead to different similarity judgements of objects in a non-linguistic rating task (participants had to rate the similarity of picture pairs). In contrast to previous studies we suprisingly observed no difference in categorization. It seems that the so-called Whorf effect, i. e. that language affects the way we perceive and categorize the world, diminishes rapidly over the time speakers are exposed to a different language system such as, in this case, German.

Read more: The decreasing Whorf-effect: A study in the classifier systems of Mandarin and Thai

Jun 212012
 

Thorsten Kahl, Johann Wolfgang von Goethe-Universitaet, Frankfurt am Main, Germany

Journal of Unsolved Questions, 2, 2, Open Questions, 7, 2012 (Received 21.03.2012, accepted 07.05.2012, published online 21.06.2012)

This open question emerged from a footnote I wrote questioning the Spartan civil and political rights in archaic times. Plutarch’s biography of Lykurgos soon became my main source because he describes details about archaic Sparta which can barely be found in other authors’ works. This makes Plutarch indispensable for me. But it is also a problem in source of criticism because we cannot verify or falsify Plutarch’s Life of Lykurgos by comparing it to contemporary, archaic sources – there are none. …

Read more: Is Plutarch a Trustworthy Source for Archaic Sparta?

Mar 312012
 

Wolter Seuntjens, Dutch Academy of ‘Pataphysics, Amsterdam, Netherlands
Journal of Unsolved Questions, 2, 2, Open Questions, 4, 2012 (Received 05.02.2012, accepted 27.03.2012, published online 31.03.2012)

In the German language, when referring to an artistic representation of a naked human body, the noun ‘Akt’
is employed. This word was not always used to denote such an artistic representation. The combination of
questions – (1) when, (2) where, (3) by whom, and (4) why was the noun ‘Akt’ first used in this particular
meaning – was the starting point of my quest. This article chronicles the inception of the problem and the
vain attempts to solve it. In short, it is the story of the ‘null result’ of ‘Akt’ research, so far.

Read more: Why ‘Akt’ and Why Not ‘Nackt’?

Feb 182012
 

Anne Jaekel and Robert B. Sim

MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, UK

Department of Pharmacology, University of Oxford, UK

Journal of Unsolved Questions, 2, 2, Articles 12-18, 2012 (Received Nov. 21st 2011, accepted Jan. 19th 2012, published online Feb. 18th, 2012)

The lung surfactant collectin proteins SP-A and SP-D have been shown to interact with phagocytic cells, such as macrophages and dendritic cells to facilitate uptake of pathogens and apoptotic cells. However, the mechanism by which the collectins interact with the phagocytes and which surface molecules on the phagocytic cells are involved is not yet clear. In the present study, we demonstrate the interaction of SP-A and SP-D with phagocytic cells including human monocyte-derived macrophages and immature dendritic cells. Results show that both proteins bind in a similar manner to both cell types. A prominent 20-22 kDa doublet band was observed on SDS- PAGE analysis as the major Ca2+ -dependent ligand for SP-A and SP-D on both macrophages and dendritic cells. However, we were unable to identify the proteins involved.

Read more: The human lung surfactant proteins A (SP-A) and D (SP-D) share similar binding mechanisms and common ligands on macrophages and dendritic cells

Dec 282011
 

Sonja Landertshamer, Clemens Schwarzinger
Johannes Kepler University Linz, Austria

Journal of Unsolved Questions, 2, 1, Articles 5-8, 2012 (Received November 8th, accepted December 3rd, published online December 27th 2011)

2,4,6-triamino-1,3,5-triazine (melamine ) was first prepared in 1834 by Liebig. It has already been used for several decades for the production of melamine-formaldehyde resins and has therefore gained industrial importance. Particularly, during the last years new possibilities for the cross-linking of melamine have been developed to replace harmful formaldehyde. The synthesis of epoxy modified melamine derivatives is one possibility for this purpose. 2-Diallylamino-4,6-bis(dimethylamino)-1,3,5-triazine was chosen as difunctional starting material, whereat solubility in organic solvents is enhanced by the use of the N-alkylated product. Epoxidations of the allyl functionalities were carried out using several common epoxidation agents. Partially, conversion took place forming mainly by-products like substituted hydroxyl amines and hydroxy triazine derivatives. Nevertheless, epoxidation of double bonds took place forming different epoxy containing structures, which may be useful starting materials for further conversions.

Read more: On the Oxidation of Allylmelamines

Dec 032011
 

Lorenz Adlung

BioQuant Insitute, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
Zentrum fuer Molekulare Biologie der Universitaet Heidelberg, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany

Journal of Unsolved Questions, 2, 1, Articles 1-4, 2012 (Received October 17th, accepted November 30th, published December 3rd 2011)

The protein CheB is an integral component of sensory adaptation in the chemotaxis system of Escherichia coli. It catalyzes demethylation of the chemoreceptors thereby opposing the effect of ligands on kinase activity. The kinase enhances the activity of the methylesterase via phosphotransfer, thus creating a negative feedback. Although CheB phosphorylation depends on the receptor state, it is not essential for precise adaptation. Therefore, the feedback mechanism is proposed through modeling to compensate for protein fluctuations in the chemotaxis network.
Swarm plate assays revealed that chemotaxis performance in general was even more robust against deviations of single protein concentrations than predicted. However, phosphorylation deficient mutants of CheB still enabled an appropriate chemotaxis response as compared to wild type CheB. Furthermore, when simulations were recoded to include CheB phosphorylation, there was no effect on swarming. Hence both, measured and calculated swarm efficiencies indicate that CheB phosphorylation does not improve robustness of chemotaxis against perturbations in protein levels.

Dependence of E. coli Chemotaxis on CheB Phosphorylation in Silico and in Vivo

Keywords: Bacteria, Chemotaxis, Feedback, Robustness

Dec 032011
 

Christof Troeltzsch, Bliesenrader Weg 5, Born/Darss, Germany

Journal of Unsolved Questions, 2, 1, Open Questions, 3, 2011 (Received November 3rd 2011, accepted November 25th 2011, published December 3rd 2012)

While working on the doctoral thesis about chelates of zirconium and hafnium – cf. [1] for preparation of the ligands and [2] for preparation of the chelates – we made an observation which could not be explained and therefore was only described in the doctoral thesis of Christof Troeltzsch, Leipzig, 1960, in the following way: ….

Read more: Which Intermediate Product Causes the Blue Colouring in a Grignard Reaction Involving Zirconium Chelates?

Oct 032011
 

Michael Kurz, Naturkundliche Gesellschaft, Hallein, Austria (e-mail: michael.kurz@gmx.at)

Journal of Unsolved Questions, 2, 1, Open Questions,1-2, 2011 (Received August 25th  2011, accepted September 4th 2011, published September 28th 2011)

If one looks at the stars, it seems astonishing that their velocities as well as those of galaxies are negligible compared to light velocity after almost 14 billion years of gravitation and expansion of the universe. In fact, it seems that there is a very fine tuning between these two cosmic phenomena….

Read more: Are Planck-particles the primordial particles of matter in the universe?

Jul 232011
 

Lan Cheng

Institute of Physical Chemistry, Johannes Gutenberg-University Mainz, Staudinger Weg 9, D-55128 Mainz, Germany
Journal of Unsolved Questions, 1, 2, Open Questions, 12-15, 2011 (Received July 18th  2011, accepted July 20th 2011, published July 23rd 2011)

Go (’weiqi’ in Chinese and ’igo’ in Japanese) [1] is an ancient board game originating from China that has been widely played in east Asia. Nowadays Go is being more and more popular throughout the world. In contrast to many other strategic games including chess that have been con- quered by modern computers many years ago, Go remains a formidable challenge to artificial intelligence [2] due to the enormous branching factors of the game tree and, perhaps more importantly, the lack of proper evaluation criteria…

Read more: Is Computer Go Solvable?

Keywords: Go, branching factors, artifical intelligence

Jul 232011
 

Wolter Seuntjens, Karolina Hansen

Dutch Academy of ’Pataphysics, Amsterdam, Netherlands
Friedrich Schiller University, Jena, Germany
Journal of Unsolved Questions, 1, 2, Open Questions, 15-16, 2011 (Received July 19th  2011, accepted July 21st 2011, published July 23rd 2011)

Theory of mind (ToM) is the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge, etc.—to oneself and others, and to understand that others have beliefs, desires, and intentions that are different from one’s own[1]. There is controversy over the question whether animals other than humans have a ToM. The question is important when assessing the status of humans within the animal kingdom. The social tool of faked orgasm seems to be unique to human beings and thus it is a strong test for the demarcation of human versus animal…

Read more: Do Female Bonobos Fake Orgasm?

Keywords: Theory of Mind, deception, orgasm, bonobo