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Urbanism in Hanoi

January 9th, 2010 by aft1

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.

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The mechanisms behind plant interactions

December 20th, 2009 by aft1

Plants cannot move.  This limitation causes plants to develop various mechanisms for adapting to their surroundings, attracting and repelling other organisms, absorbing and releasing nutrients and chemicals, and using these organisms and chemicals for their benefit and sustenance.

A plant’s interaction with the environment happens at the surface.  Substances enter and exit through diffusion or active transport by transport proteins embedded in the surface membrane of the plant.  The border control operation is mediated by the selective binding affinity of transport proteins and also by a membrane potential that exists across the membrane.  This membrane potential drives directional flow, providing a pulling force.

At the surface are other sensory receptors that activate a protein kinase chain reaction to produce a particular response in this part of the plant.  These chain reactions often multiply a signal to initiate a systematic response in other parts of the plant as well.

The mechanism for carrying substances or chemical signals to other parts of the plant is the vascular network of xylems and phloems.  Water and minerals enter into the root system and travel upwards through the xylem into other parts of the plant.  Sugars are produced in the leaves through photosynthesis and move from the point of sugar production to sugar storage via the phloem.

vascular network of a plant

vascular network of a plant

The xylem sap, which contains water and minerals, is pulled upward through the xylem by water escaping through the stomata located at the surface of the plant.  The water escapes when sunlight strikes the surface of the plant, causing the water to evaporate through the stomata.  As the water evaporates, the water curves around the mesophyll cells, increasing surface tension, which causes increased water loss from the mesophyll cells.  This water loss causes mesophyll cells to bring in more water from the xylem, which leads to the negative pressure pull of water into the roots.  When the water comes in through transport proteins embedded in the epidermis of the root system, it also brings in the nutrients and substances necessary for the plant to survive.

When sunlight strikes the surface of a leaf, it also activates an electron donated by a water molecule, which flows down an electron transport chain in the thylakoid membrane of chloroplasts found in mesophyll cells.  The electron transport chain ends with the the conversion of NADP into NADPH and the release of O2.  The Calvin Cycle then combines NADPH with CO2 and converts it to glyceraldehyde 3-phosphate, a 3-carbon sugar, that is recombined to form sucrose and starch.  Starch is stored as reserve energy for the plant, and sucrose is immediately transported to other parts of the plant for use and storage.

Sucrose is transported throughout the plant via phloem.  The phloem consists of sieve tubes and companion cells.  The sieve tubes are made up of sieve cells that have plasmodesmata at each end to allow substances through.  The companion cells regulate the substances that enter and exit the sieve tubes.  Substances move through the sieve tube by positive pressure flow, a push factor caused by density.  A high concentration of organic substances at the source creates a diffusion gradient that draws water into the cells.  This sugar-water sap moves by bulk flow through the sieve tube from the sugar source to the sugar sink.

In a living system, the architecture is found in the thickness of the wall, through the interactions between the elements that make up the thickness, and through the communication that happens in the void between the opposite walls.  Communication happens by channeling forces that already exist, and making these forces do all the work.  The intelligence is found not only in the complexity of the system, but in how little effort is required for the system to sustain itself over time.

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Cor-Ten

September 22nd, 2009 by aft1

A singular substance creates a visible dialogue between the past and the present.  It changes every day.  It flows onto the pavement like a river delta leaving behind striations cut in the color of orange.  Massive yet graceful, Cor-Ten speaks in echoes and pattering of rain drops.

Cor-Ten (or weathering steel) is a steel product that oxidizes very rapidly, then maintains a stable, dark-brown, rusted surface.  Alloyed with copper (Cu) and chromium (Cr), Cor-Ten resists atmospheric corrosion by developing and continuously regenerating a protective layer of rust on its surface that inhibits deeper penetration by atmospheric agents when subjected to the weather.  Made primarily of steel, or iron oxide (Fe2O3) with a little bit of carbon (C), Cor-Ten has high tensile strength and compressive strength, allowing it to be used as a structural component for buildings, sculptures, and bridges.  The addition of chromium increases hardness and melting temperature and prevents corrosion by forming a hard oxide layer on the surface.  Consequently, Cor-Ten exhibits much greater resistance to atmospheric corrosion than unalloyed steels.1

Richard Serra, Torqued Ellipse, UCLA

Richard Serra, Torqued Ellipse, UCLA

The surface texture of Cor-Ten depends largely on the nature of its surrounding atmosphere.  The macroclimate (industrial, urban, or maritime) drastically changes the effectiveness of the material against corrosion.  Although Cor-Ten resists weathering by rain, snow, fog, and ice, it cannot stand up to a constantly submerged environment or the presence of salt.  The readiness of salt to take up moisture maintains a constantly damp environment on the metal surface, causing it to rust beyond its ability to regenerate a protective layer.  As a result, Cor-Ten should not be used within 2km of the coast line.  In a marine environment, applying conventional coating and performing maintenance works on the Cor-Ten by removing salt buildup quickly gives it the chance to regenerate its protective rust layer.

Cor Ten

Cor Ten

The orientation of the Cor-Ten (exposed to or shaded from weathering, vertical or horizontal position) also affects how the material stands up to the climate. Cor-Ten surfaces facing south and west and those exposed to frequent wet and dry cycles develop a smoother fine-grained texture.   North and east facing surfaces and those that are shaded develop a coarser texture.2

Lastly, the connection points between panels of Cor-Ten must be detailed such that weld-points and bolts weather at the same rate as the Cor-Ten.  Using welded consumables matching the base material ensures that the welded joint also resists corrosion.  Threading bolts made of weathering steel into the Cor-Ten material prevents the formation of localized electrochemical cells.  (When a metal loses electrons, it becomes positively charged and quickly reacts with oxygen to create iron oxide, or rust.  If this process happens too rapidly, the Cor-Ten cannot regenerate its protective layer in time.)3  In addition, applying sealants around the joints stops capillary action from inflicting permanent moisture damage by corrosion.

Although a finicky material to deal with, Cor-Ten expresses every architect’s desire to design the building to express the passing of time, poetically, beautifully.

1. Thyssen Krupp.  COR-TEN.

2. Finishing.com.  “Marine environment effects on corten steel in relation to public art”

3. NASA. Corrosion Technology Laboratory.

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Weathering

September 15th, 2009 by aft1

“Finishing ends construction, weathering constructs finishes.” – Mohsen Mostafavi

Museum pieces exist in our minds as objects frozen in time.  Timelessness describes purpose, character, and memory.  The artist’s intention remains the same.  Like a character in a story, an artwork conveys the same message each time it is read, even if the response changes.  Images recorded in our memory show up again as time passes, but they are no different than the first recording.

However, everything exists in time.  Everything undergoes weathering.  A material undergoes weathering as a result of intrinsic and extrinsic characteristics including composition, climate, and human influence.  Over time the natural environment interacts with the chemical composition of a material.  Humans unknowingly wreck havoc to ancient treasures by exposing them to light, humidity, pests, inappropriate temperatures, mishandling, and chemicals in the environment, in the name of learning, earning, exhibiting, and conserving.  Driven by the forces of the environment in contact with the make-up of the material itself, weathering causes materials to deteriorate.

Left uninterrupted, the process of weathering degrades the artwork as well as the component materials.  But is degradation necessarily the outcome of weathering?  Can weathering augment the value, beauty, or effectiveness of a piece of artwork?  Humans express a special appreciation for aged wine, worn clothing, ivy-covered brick walls, and the remains of ancient temples.

The city of Petra lies in the southern desert of Jordan, deep in a valley surrounded by steep sandstone walls.  Built around 2000 years ago, the Roman-style Theater of Petra uses sandstone cut from the local cliffs.  Employing the techniques recorded by the great Roman engineer Marcus Pollio Vitruvius, the Romans built the theater with such precision that the level of the original surfaces can be estimated from the current receded surfaces.  Weathering of the sandstone surfaces by climatic influences like sunlight and moisture has caused erosion and cracking.  Foot tread has also sped up the rate of erosion in recent years, demonstrated by the increasing rate of erosion of surfaces.  However, the general rock composition has proven to be the greatest factor in the rate of weathering, followed by the concentration of iron oxide present in the sandstone.1

Petra Theater

Petra Theater today

Petra Theater

Plan of Petra Theater

The most obvious sign of the attractiveness of weathering in Petra is the presence of foot traffic that has resulted in the increasing rate of weathering.  In 1990, at least 15% to 20% of the sandstone in the Theater displayed the original stonemason dressing marks.  Ten years later, only 5% to 10% of the sandstone exhibited similar markings.  Neither the result of climatic change nor compositional change, the acceleration of erosion – especially at locations along the tourist route – points to increasing tourist fascination with these ancient ruins.  A thousand years of history flash before one’s eyes in passage through this ancient space.

Time continues to captivate humanity.  Perhaps the art of weathering has the potential to revolutionize the way that artists conceive of and create their masterpieces.

1     Turkington, Alice V.  Stone Decay in the Architectural Environment. “Petra revisited: An examination of sandstone weathering research in Petra, Jordan.”

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Evolution of the Museum

September 8th, 2009 by aft1

Museums serve as the barometer for the condition and values of the society.

Beginning in ancient Greece in the 5th century BC, the first museums are temples.  They housed collections of statues to individual gods or goddesses serving as protectors and sustainers of the community as well as monumental inscriptions and paintings depicting successes of the military.  The Greek museum also included collections of scholarly materials, such as the Library of Alexandria, built for the study of music, poetry, anatomy and philosophy.  The Romans took the idea of collecting prized treasures into private villas in Rome and in public places such as the Acropolis.

MuseumThe activity of collecting eventually evolved into conserving, restoring and protecting the artworks during the Dark Ages, when they were stored in churches, castles and caves so that they would not be destroyed.  Not only were these places considered important for the feudal kingdoms, but they were fortified, holy, and symbols of a kingdom’s power.  Many of these artworks were given to private collectors after the period of warfare, who usually had an appreciation for art and kept works of art as status symbols.

Collecting evolved into exhibiting during the 1800s when many second-hand collectors began showing them off in galleries and bequeathing them to larger museums.  The Age of Enlightenment and Industrial Revolution had also begun in the 1700s, creating major transformation in the fields of agriculture, manufacturing, mining and transportation, which profoundly affected the socioeconomic condition of many people.  Around this time, many countries began to amass large amounts of artwork to establish major royal museums – including the British Museum in England, Louvre Palace in France, and El Prado Museum in Spain – as symbols of national pride, to be exhibited to citizens and visitors.

A radical shift in politics and economics in the late 19th century and early 20th century led to an era known as the Museum Age.   With the rise of Nazism and Communism which sought to destroy art and the freedom of expression came many new museums focused on scientific discoveries and artistic developments.  The museum once again evolved, though this time its purpose went beyond exhibiting to researching, educating and interpreting.  Designed to attract specific demographics and to give each visitor a uniquely personal experience, some museums in the YouTube generation have even introduced interactive exhibits that engage the visitor in activities contributing to the art itself.

Beginning with the intention of collecting art, then showing art in an unbiased manner, museums are now retelling art, reinterpreting history, and engaging the viewer in critical dialogue.  As if a natural gradient has been set into motion, museums are becoming increasingly more personal.  The range of media is growing wider, yet the intensity of study is growing deeper.  As a barometer for the condition and values of society, contemporary museums demonstrate the voices of 6 billion people of this world calling for personal development and individual expression.

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The Science behind the Enjoyment of Food

September 7th, 2009 by aft1

I cannot control the sense of euphoria from eating a good meal.  In fact my condition is quite scientific.  We know since elementary school that we have taste buds.  Our taste buds have gustatory receptor cells that can detect taste qualities, namely saltiness (sodium ions), sourness (acidity, or amount of hydrogen ions), bitterness (some ligands), sweetness (sugar groups), and savoriness (glutamic acid), and the concentration of each.  The cells send signals with the taste information through cranial nerves to the gustatory cortex.  The gustatory information is then conveyed to the orbitofrontal cortex, which sends it to the hippocampus, nucleus accumbens, and the amygdala, which together make up the limbic system.

The limbic system is a set of brain structures that control emotion, behavior, long term memory, and the sense of smell.  It is responsible for turning our perception of taste into an experience of a lifetime.  My limbic system became especially excited one time when I was with a friend at the oldest restaurant in the world, Restaurante Botin in Madrid.  It had four floors, 2-feet-wide stairs that bypassed 6-foot-high openings, and multiple dining rooms, one of which was the old wine cellar, and the host took us to a table here.  But what made this dining adventure into an experience of a lifetime was the way that the menu choices engaged the senses.

Using unique methods of preparation and a refined list of ingredients, every choice looked and smelled like a slice of heaven.  I decided to try the house specialty, the cochinillo asado (roast suckling pig).  Prepared on a traditional oak wood fired stove from 1725, the cochinillo asado tasted incredibly moist and tender, complemented by a deliciously crispy layer of crackling skin.  An added texture of roasted potatoes and slightly sweet sangria made the meal explosively sensational.

Thanks to the hard-working limbic system, I was able to not only experience the emotions of happiness that began to overwhelm me and the smell of roasted meat that permeated throughout the space, but I also retained the taste quality titled “cochinillo asado” in my library of sensations and the recollection of this night in my long-term memory.

Like a good meal, good architecture is more than a list of ingredients.  From a combination of well-chosen ingredients and a creative method of preparation comes an experience to be felt, a recipe that stimulates response, and a moment to be remembered.

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Membrane Structure and Function

September 2nd, 2009 by aft1

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.

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The Origins of Life

August 31st, 2009 by aft1

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.

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