Changing the template of my blog

I have just received feedback from my students that my blog looked rather bland. Hence, I adjusted the background of my blog using a downloaded image of the Aurora Borealis (the Northern Lights), a beautiful and captivating natural phenomenon. Hopefully, it gives my blog a more colourful, albeit mystifying feel.

The eldest child is the smartest!

I found an interesting article in the International Herald Tribune, and it was found that the eldest child score on average three points higher than his/her other siblings in IQ tests. The reason is due to family dynamics rather than biological factors, e.g. changes in gestation processes. I guess the pressure is on the eldest to learn as much as possible about life in general, in order to guide his/her younger siblings. For those who are the eldest, do rejoice over the fact that you may be more intelligent. For those whom are not the eldest, you can always seek the counsel of your eldest sibling! Be comforted that you have your eldest sibling around to hold your hands and guide you through obstacles when you need him/her the most!


Citations

Benedict Carey. Family dynamics, not biology, behind higher IQ. International Herald Tribune accessible at http://www.iht.com/articles/2007/06/21/africa/siblings.php

Life Science queries

Students in my lessons, feel free to voice whatever queries, thoughts or views you may have during your course. I will try to respond ASAP. Remember no vulgarities, personal attacks, flaming or anything that is detrimental to the discussion.

Cancer, metastasis and the entire business of vesicle trafficking

Vesicle trafficking plays a part in cellular processes. Vesicles are formed, undergo expansion and completion, and finally participating in lysosomal degradation. Vesicles are involved in this process known as autophagy. Autophagosomes are double-membrane vesicles. In a paper published by Takahashi et al in Nature Cell Biology, it was found that Bif-1 interacts with Beclin-1, and together with ATG-5, is involved in the formation of autophagosomes. Loss of Bif-1 led to abrogation of autophagy, and the arising of spontaneous tumours in mice (Takahashi et al, 2007). It was also found that during the process of carcinogenesis in mice, there was reduced autophagic activity (Schwarze and Seglen, 1985). Indeed, it's interesting to note the part played by vesicle trafficking pathways in tumorigenesis. Vesicle trafficking pathways may play a part in metastasis. Jiang et al has found that the regulation of matrix metalloproteinase-1 activity was achieved by dynamin-mediated endocytosis (Jiang et al, 2001). The study of vesicle trafficking pathways in cancer and metastatic cells will gives us insights into how they actually assist in the latter's functions.


Citations

1) Yoshinori Takahashi, Domenico Coppola, Norimasa Matsushita, Hernani D. Cualing, Mei Sun, Yuya Sato, Chengyu Liang, Jae U. Jung, Jin Q. Cheng, James J. Mul, W. Jack Pledger & Hong-Gang Wang. Bif-1 interacts with Beclin 1 through UVRAG and regulates autophagy and tumorigenesis. Nature Cell Biology, 23 Septemter 2007

2) Schwarze, P. E. & Seglen, P. O. Reduced autophagic activity, improved protein balance and enhanced in vitro survival of hepatocytes isolated from carcinogen-treated rats. Exp. Cell Res. 157, 15–28 (1985)

3) Jiang A, Lehti K, Wang X, Weiss SJ, Keski-Oja J, Pei D. Regulation of membrane-type matrix metalloproteinase 1 activity by dynamin-mediated endocytosis. Proc Natl Acad Sci U S A. 2001 Nov 20;98(24):13693-8.

Really stranger than friction

Read an article in Times about the trial of Krystian Bala, a novelist of a macabre best seller, containing a story of a murder of which he was responsible for three years ago. He murdered a lover of his former wife. Apparently, the murder victim was tortured to death, presumably by asphyxiation and drowning, whereby a noose was tied around his neck and he was being thrown into a river. A similar account of the murder was written in a book published by Bala titled Amok.

Yet, this account of a crime involving a jealous lover was a poignant reminder to me. During my college days, I was mistaken by a jealous fellow as a boyfriend of a female friend who was my orientation group mate. Yes, I treated her as a friend, but no more than that. This guy actually claimed that I looked like a playboy and told a martial arts-trained friend of his to fix me. It happened that this martial arts trained friend of his was also my friend too. It was from the latter that I found out what happened.

Guess when one is in the deeper throes of passion does he lose his rationality.

Citations
Jail for author of ‘a perfect crime’
http://www.timesonline.co.uk/tol/news/world/europe/article2395523.ece

The driving force of morality

It has been put forth by Creationists that one of the driving force for the existence of a god is the existence and nature of morality. My first response to this line of arguement is to re-examine the driving force of morality, as in why the need for morality arises?

However, let's begin with this important question - What is morality? Referring to the Stanford Encyclopedia of Philosophy, it refers to a code of conduct put forth by a society or a religious group or normatively refer to a code of conduct would be put forward by rational persons under specific conditions.

The agglomeration of individuals in societies can be argued as the driving force for the need for morality. Simply put, in order for society to function and for its members to thrive, there is a need for the latter to abide by a certain code of conduct so that his/her fellow members will benefit or will be free from harm. Take for instance the traffic code of conduct whereby drivers are exhorted to drive safely by keeping within speed limits. Clearly, the safety of the other members of the society is likely to be preserved if such a code of conduct is in place.

The arising of civil societies is seen as the apex in evolution of a society. There is a paradigm shift away from a more individualistic outlook to a more socially conscious perspective in as far as members are concerned. Thus, going by the London School of Economics definition of civil societies, a civil society is one which revolves around shared interests and values, whereby collective action is taken.

In essence, the society is seen as the driving force of morality for the simple reason that morality is seen as the means to the society's end (good).

Citations
1) The Definition of Morality. Stanford Encyclopedia of Philosophy http://plato.stanford.edu/entries/morality-definition/

2) Definition of Civil Society. London School of Economics
http://www.lse.ac.uk/collections/CCS/what_is_civil_society.htm

Concepts in peer to peer computing: A hierarchical model of file distribution in peer to peer networks through designation of sub-hubs

Abstract

The use of an algorithm to designate sub-hubs within a peer to peer network will help to lessen some of the problems that networks face i.e. excessive traffic within the network leading to situations such as upstream congestion, which results in the deterioration in performance of other softwares that upload information into the Internet. Besides, the sub-hubs will ensure that the file is being distributed throughout the network as the latter will be relatively free from the constraints of congestion. The algorithm is as follows:

1) Status of user node is determined in terms of percentage of file downloaded;
2) Scan the network for other nodes whose download status is of a certain percentage e.g. 10% greater than the user;
3) Generate a distribution curve of the other nodes over this percentage range;
4) Determine the highest frequency of nodes over the range (if the frequency of nodes over the range is determined to be too low, steps 2 to 4 is repeated, but the network is scanned for nodes whose download status range is greater than the current one e.g. 20% > 10%);
5) Designate these nodes as sub-hubs;
6) User will download from these sub-hubs;
7) else (download from any user irregardless of download status with the part of the file in demand)

Introduction

Peer to peer networks are a popular way to transfer files, and is quite likely, they will be here to stay for quite a long time. They are different from the traditional client-server system, adopting a more decentralised mode of file distribution whereby peers act as equal, merging the roles of server and clients. A number of peer to peer software are in popular usage, e.g. Bittorrent, Emule and many others. This is not to say that peer to peer file transfer is free of any problems of its own. The growth in peer to peer traffic results in network congestion. Upstream traffic congestion can occur in circumstances when a particular user within the network is uploading the file to a large number of peers. This results in a large upstream to downstream ratio. This will likely result in congestion in the upstream link. Interestingly, it has also been shown that 60% of all Internet traffic is being driven by peer to peer traffic (Briere and Hurley, 2007).

A hypothetical scenario and the solution

Consider the network in Figure A. One seed (red node) with 100% of the file is being swarmed by downloaders. The seed is swarmed by 2 downloaders (green nodes) with 90% of the file, 3 downloaders with 70% of the file (blue nodes), 4 downloaders with 20% of the file (brown nodes) and 5 downloaders with 10% (magenta nodes) of the file. There is high likelihood that the seed will experience upstream congestion with dire consequences in their respective networks. The aforementioned algorithm serves to reduce the likelihood of congestion through designation of sub-hubs. In figure B, you can see the frequency distribution of the nodes in terms of percentage of file downloaded. In Figure C, you will be able to see what the algorithm does, i.e. to designate sub-hubs in a hierarchical fashion. You will notice that instead of the seed supplying the file to everyone, it will instead supply the file to the 90% completed downloaders, and the latter will supply the file to the 70% completed downloaders, who will supply the file to the 20% completed downloaders, who will lastly supply the file to the 10% completed downloaders. It can be seen in a hierarchical sense, nodes with a certain percentage of file downloaded that are at the lower echelons of the hierarchy will act as sub-hubs, which can relieve upload traffic from the main hub (the seed or those who have nearly completed downloading the file). It should be noted that the nodes can progress through the hierarchy as a greater percentage of file is being downloaded with time.

Discussion

This algorithm, which can be adopted in peer to peer softwares, is suggested as one of the possible solutions to ease some of the problems inherent in networks with heavy peer to peer traffic. However, it is not really known at this point of time the speed of file download relative to the current peer to peer softwares in use. However, prediction is that the speed of download should be comparable vis-a-vis current peer to peer softwares. Firstly, it will be relatively freer from congestion problems as which is the case with current peer to peer software. Secondly, at each step of progression of download, a source of sub-hubs will increase the speed of file download. It has also been pointed out that one of the main concerns on peer to peer networks is that the speed of download slows down towards the end. However, it's still not known whether this algorithm will be able to address this problem. Finally, it can be seen that this algorithm retains the essential features of the mainstream peer to peer software, i.e. users upload and download files simultaneously, whereby they function as downloaders from sub-hubs above them in the hierarchy (in terms of percentage of file completed), whilst they themselves act as uploaders to users below them in the hierarchy.

Citations
Briere, D and Hurley, P. The Bleeding Edge. Networkworld.com