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“The unexamined life is not worth living.” – Socrates (469 BC – 399 BC)
 

Posts Tagged ‘Architecture and Urbanism’

Urbanism in Hanoi

Saturday, January 9th, 2010

Hanoi is a place of dichotomies. Where the average university graduate earns only $2.90 per day, the city also has some of the most expensive real estate in the world. Motorbikes that cost thousands of dollars can be found all over the streets, but sometimes four or five people sandwich themselves together on top of the driver’s seat. The smallest taxis tend to carry the greatest load – a Vietnamese family, and their extended family – while the largest taxis tend to carry only a few – the tourists who (unknowingly) pay the extra price for the bigger car.

The greatest dichotomy of all is the fact that Hanoi is the capitol of one of the purest Communist countries in the world – Vietnam – yet the urbanization of Hanoi is almost purely based on economic forces. In my observations and casual conversations with Hanoi people, I realize that economic forces generate multiple modes of urbanism characteristic of Hanoi: generational urbanism, informal urbanism, surface urbanism, copycat urbanism, and privatization.

Typical housing in Hanoi

Typical housing in Hanoi

Generational urbanism occurs when plots of land are commonly passed down from one generation to another. Because of the exorbitant home prices in the city, Hanoi residents simply do not have the means to buy a house or a flat, so many choose to move into their parents’ home along with their spouse and children. As a result, many former French colonial mansions are inhabited by multiple multi-generational families. The house is then subdivided until it is no longer possible to make any more changes, upon which the house is sold and the money is shared between the families. These families often move to the periphery of the city where home prices are less extreme, and then work their way back into the city.

Informal urbanism involves the illegal businesses that have become permanent fixtures in the city. The perimeters of highways and streets become places of exchange. Taxi drivers invite tourists to their cars. Shops spill out into the sidewalk to increase frontage, engage the street, and increase business. Bread vendors set up shop along the side of the highway to increase visibility for commuters who might want to buy bread for the following morning’s breakfast on their way home.

Surface urbanism is the treatment of façades to create an illusion of greater sophistication. Most sites in Hanoi are infill conditions, meaning that they have a front side and a back side. To create the illusion of greater sophistication, owners spend most of the construction costs on the front façade and save money on the side elevations by leaving them blank. Banks take it a step further and articulate their side elevations in addition to giving their facilities a grand staircase. Taxi drivers use the same approach to lure tourists into their cars. Usually newer, cleaner, and bigger, the scam taxis appeal to tourists who end up paying according to a marked-up meter.

Copycat urbanism runs rampant in the city center. The lots in the city are divided (generationally) into 20-foot-wide strips that vary in length anywhere from 40 feet to over 120 feet. These homes are often built to 6 stories high. Less than a mile from the Intercontinental Hanoi Hotel where I stayed was one of the typical 20-foot-wide lots with a peculiar-looking house built with a baby-blue façade accented by an orange plane. A few blocks away I found exactly the same baby-blue façade accented by an orange plane on another residence. In Hanoi, architects are one of the most respected professions, and architects are paid relatively high. Consequently, many Hanoi people cannot afford to hire an architect and most of the residences are not designed by architects; instead, the owner searches for an existing house that he likes the most and hires a construction firm to make a replica of it on his lot.

Privatization – ironically initiated by the Communist government – provides the government with a steady source of income. Taking advantage of the high real estate prices, the government actively sells off state-owned property to private investors and buyers. Current studies show an increasing trend in the demolition of existing French colonial buildings upon the purchase of a new lot to make way for taller buildings and denser inhabitation.

The economic forces that shape these modes of urbanism operating simultaneously create the current situation of hyper density and apparent chaos. A struggle to increase their personal wealth and personal space has simultaneously caused Hanoi to shrink. It has already shrunken quite significantly.

Membrane Structure and Function

Wednesday, September 2nd, 2009

The best architectural curtain walls are built to resist air and water infiltration, wind forces acting on a building and their own dead weight, while allowing daylight to penetrate into the space.  They are also very expensive, create an enormous amount of heat build-up, and function in binary.

A film of roughly 8nm in thickness (that is, 1/8000 the thickness of a sheet of computer paper), cell membranes have an amazing ability to regulate the substances that enter and exit a cell.

Fluid mosaic model for membranes, with phospholipid bilayer penetrated with proteins

Fluid mosaic model for membranes, with phospholipid bilayer penetrated with proteins and supported by cytoskeleton.

Cell membranes are made up of two layers of phospholipids.  Phospholipids have hydrophilic (water-loving) heads and hydrophobic (water-repelling) tails.  Water exists on both the exterior and interior sides of the membrane.  The hydrophobic tails hide behind the hydrophilic heads on both sides of the membrane, forming a non-rigid boundary around the inside of the cell.  This non-rigid membrane is held in its shape by microfilaments of cytoskeleton.

However, not all membranes are the same; some are thicker than others, some have higher percentage of proteins, and others have different kinds of phospholipids.  After each protein is synthesized in the ribosome with the information coded in RNA translated from the DNA, the proteins are individually inserted into the phospholipid bilayer with their hydrophilic ends sticking out.

Proteins determine most of the membrane’s functions.  One protein can have several functions.  Integral proteins – those that penetrate through the phospholipid bilayer – regulate what comes in and out of a cell.  Peripheral proteins are like appendages bound to the surface of the membrane.  Integral proteins include:

1. Transport proteins (acting as a diffusion channel or as a pump to bring substances into and out of cells),

2. Enzymes (working individually or in teams to carry out sequential steps of a metabolic pathway through induced chemical reactions),

3. Signal transducers (reading the message from a chemical messenger to relay a message to the inside of the cell),

4. Cell-to-cell recognition (serving as ID tags recognized by membrane proteins of other cells, especially useful in producing cells for a specific tissue or organ),

5. Intercellular joints (allowing cells to hook up in various kinds of junctions), and

6. Attachments to extracellular matrix (maintaining cell shape).

Peripheral proteins can also act as enzymes and transporters, but they only interact with different parts within the same cell.  They help transport small hydrophobic molecules, toxins, and antimicrobial peptides.

A cell membrane is a fine example of a supramolecular structure, where many molecules are ordered into a higher level of organization with emergent properties beyond those of the individual molecules.  It is architecture.

The Origins of Life

Monday, August 31st, 2009

I must begin a blog about life with an examination of how life began.  Instead of beginning with a theory, whether Big Bang or creation, I would like to introduce the beginning of life at a point in which humans have the capacity to fully understand.  This beginning is molecular architecture.

Molecular architecture is based on carbon (C) bonding with the elements hydrogen (H), oxygen (O), sulphur (S), nitrogen (N), and phosphorus (P) in different organizational configurations to produce complexity.  These elements bonded together under heat, pressure and lightning in the early atmosphere to produce the fundamental molecules of methane (CH4), hydrogen gas (H2), ammonia (NH3), and water vapor (H2O) that were essential for generating the amino acids and hydrocarbons essential for life to begin.  Varying in length, single/double bonding, branching, rings, and positioning, molecules of many types could emerge out of these simple elements.

These molecules could not have emerged without carbon.  Its tetravalence allows carbon to bond covalently with four other molecules to form 3-dimensional polymers.  With the versatility of a spider joint used in curtain wall construction, carbon can even bond covalently with other carbons to form increasingly larger chains.

Seven functional groups have the ability to form every type of carbohydrate, lipid, protein, and nucleic acid.  They are hydroxyl (OH), carbonyl (CO), carboxyl (COOH), amino (NH2), sulfhydrl (SH), phosphate (PO4) and methyl (CH3).

When a carbon atom (C) bonds covalently with an amino (NH2), a carboxyl (COOH), and a sidechain (R, of which there are 20 types), an amino acid emerges which has properties that have not existed before in its base polymers.  Multiple amino acids bonded together form polypeptides, and polypeptides form proteins.

The sequence of the polypeptide is dictated by the DNA (deoxyribonucleic acid) within a cell’s nucleus.   DNA is formed by a nitrogenous base bonded to a sugar which is bonded to a phosphate.  The sugar and phosphate form the backbone for the nitrogenous bases.  The sequence of these nitrogenous bases transcribes directly into the amino acid sequence of the polypeptide.

Proteins have four degrees of structure, each of which is determined by the amino acids that make up its polypeptides, and each one occurring at a greater scale than the one before.  The first degree is the organization of their amino acid sequence.  The second degree, an increase in scale of one degree, is the formation of an alpha helix or a beta sheet via folding or coiling.  The third degree structure is the overall shape of the polypeptide, composed of many alpha helixes and beta sheets.  The fourth degree structure is the overall protein shape.  The protein shape determines its functionality.  Proteins are instrumental in almost everything that organisms do.  Some proteins known as enzymes speed up chemical reactions, others form structures in cells, and yet others aid in storage, transport, cellular communication, movement, and defense against foreign substances.

Thus from six basic elements found in the early natural system, we have the beginnings of life, the emergence of complex organisms, and the fundamental organization and structures from which we can become inspired.