Four pages biology hmw help.

This is a group hmw. My group member already finish the first two part. I need some one to help me with my part.

1. Requriment is in the note.

2.”Project” is the first part and “infection” is the second part. This is what my group member already done.

3. My part is called “control” and “effectiveness”

4. Each of the two part needs 500 word, So total will be 1000 words at least.It’s about 4 pages.

Thank u.

Report of the exercise:

1. Description of the scene:

2. Infection:

3. Control:

Physical

Chemical

Biological

Isolation

Physiological

Pathological

Medical

Four factor model for thrive of micro-organism:

Spore – temperature – water – nutrient.

Consider these two mottos:

· The most economical way to cure sickness is not to get sick.

· The most effective way to cure sickness is by one’s own immunity.

4. Effectiveness

Use Wells – Riley parameters

Compare alternatives to current situation.

Use the Well’s – Riley model to make an initial assessment of the base infection risk.

Consider all conditions which may affect the risk of infection and propose all conceivable ways to reduce the risk.

Use the Well’s – Riley model to re-evaluate the risk.

Discuss the cost effectiveness of each of the proposed enhancement.

Methodology:

1. Literature survey

2. Modeling

3. Photographs

4. Drawings

5. Illustrations

In this group project we take subway stations as the objective of modeling. We take Hung Hom station as the delegate of all the stations in our study through literature search and field investigation. The station is not only the end of (Mass Transit Railway) east and west rail line, but also the terminal of Intercity Through Train between Hong Kong and mainland China. Most of the subway stations can be treated as a relatively closed space which is lack of natural ventilation. The Hung Hom station is a ground station with 7 island or side platform(6 for passengers and 1 for

Figure 1. The layout of Hung Hom station

freight services), has 14 exits, 22 escalators and 7 elevators. Platform doors are not placed in the station of Hung Hom[http://en.wikipedia.org/wiki/Hung_Hom_

Station

]. So the open station can be easily contacted with the outside environment. What’s more, washrooms and uncovered dustbins are set up in the platform, this required the a higher cleaning level of the station.

Figure 2. The platform of the station(Left: Island platform Right: Side platform)

Central air-conditionings are used inside or outside the station. In order to supply a better environment to the passengers, more than 2 group of ventilations will be installed in the station to reduce the concentration of CO2 and produce the concentration of O2 for about 5L per second, which is the ten times as much as normal people needed. The fresh air drawn from outside by the ventilations are filtered by the strainer, then be transformed into cold wind in fumehood and transmitted to the whole station through the driving of the running of the trains[http://www.classroom.com.hk/classroommagazine/news_channel/content.aspx?id=080425&thelang=c]. So that the concentration of CO2 in all the stations can keep within the level below the standard concentration of HK environmental Protection Department.

Table 1. Concentration of CO2 in subway stations and other public place[http://gb.cri.cn/23204/2008/04/21/3365@2028408.htm]

And the level of rush particles can be keep in a relative low level.

Figure 4. RSP comparsion between EPD(Central roadside air centre) vs MTR central station ventshaft(Daily average from 15, Mar to 2 , Apr, 2008 )

Plasma air sterilization system are installed in the Lok Ma Chau and Lo Wu station in order to develop the air quality of the indoor environment.

Infection:

According to Philip ‘study[1] , 4.4% of the 2.6 million cumulative infections that compromise the simulated epidemic happened on the subway with the allocation from commuters (3.6%) to non-commuters (0.8%) shown the table .1 that the risk factor of 78.73 per 1,000 for infection, subway commuting poses a risk comparable to working. The activity column cataloged the most important circumstances that required recording, such as whether the participant was sitting, walking, or standing; whether the train was moving or stopped; and the position of the windows and vents[2].

Table.1 Baseline source of infection results. Source:[1]

The types of possible infection are epidemic, communicable disease, building related illness and sick building syndrome in subway

Epidemic

The epidemic spreading on subway networks are focused on the multi-scale mobility network consisting of short-scale commuting flows and long range line traffic. The epidemic of the subway will enhance the risk of a pandemic as evidenced by the spread of SARS (severe acute respiratory syndrome), avian influenza and H1N1 swine influenza in the past decade [3]. Severe acute respiratory syndrome (SARS) is predominantly spread by large-droplet ((>5 microns) transmission, and airborne transmission [4]. The other pandemic(avian influenza,H1N1 virus is via the alimentary canal and respiratory tract into the human body, moreover, it can also spread by human spray and secret of the respiratory tract.

Communicable disease

The infections of the communicable disease for the subway are influenza, mumps and epidemic cerebrospinal meningitis. For the influenza, it is spreading via the air by coughs or sneezes, creating aerosols containing the virus. Furthermore, it can also be transmitted by direct nasal secretions or through contact with contaminated surfaces [5].Mumps is the contagious disease that is spreading from person to person via the get in touch with respiratory secretions, such as saliva from an infected person. If an infected person in the subway is getting the coughs or sneezes, the droplets aerosolize will enter the eyes, nose, or mouth of another person. Moreover, the virus is survived on surfaces and then be transmitted after contact in a similar manner [6].

Building related illness

Building related illness is defined illness that knowing causative agent resulting from exposure to the building air [7]. According to Zhang’s study [8], the carriage of subway in which has the number of 120 ~130 individuals that the concentration of formaldehyde is 0.13 mg/m3. The standard of indoor air quality (GB/T 18683-2002) is regulated the highest concentration of formaldehyde about 0.12mg/m3 for indoor. Moreover, the symptoms of building related illness may be specific or mimic symptoms commonly relate to the flu, including fever, chills, and coughs. Acute lung and respiratory conditions can occur. The most common symptoms observed were lethargy (57%), nasal obstruction (47%), pharyngeal irritation (46%) and chest tightness (9%) [9].

Sick building syndrome

Sick building syndrome (SBS) is defined health problems experienced by the occupants of a particular building [7]. Sick Building Syndrome can be caused by inadequate ventilation, chemical contaminants (carbon dioxide, formaldehyde and other aldehydes) from indoor or outdoor source. In the rush hours, the effect of subway’s ventilation will become badness that because it has larger passenger flow volume that make ventilation not enough to work. According to YANG’s study [10], the air quality of inside interval tunnel is worse than the platform. In interval tunnel, the concentration of CO2 in the rush hours is higher than non-rush hours (See. Figure.1). so the higher passenger flow can easy get the sick building syndromes.

Figure 1 CO2 concentration curve of interval tunnel. Source: [10]

Reference

1. Philip Cooley,Bernadette Chasteen,Et al. (2011). The Role of Subway Travel in an Influenza Epidemic: A New York City Simulation. The New York Academy of Medicine. 88 (3), 982-995.

2. Alfredo Morabia,Philippe N. Amstislavski,V, Et al,. (2009). Air Pollution and Activity During Transportation by Car, Subway, and Walking.American Journal of Preventive Medicine. 2009 (1), 37.

3.Zhongyuan Ruan,Pakming Hui, Et al.. (2013). Risks of an epidemic in a two-layered railway-local area traveling network. THE EUROPEAN PHYSICAL JOURNAL. 86 (2013), 13.

4.Hiroyuki FURUYA. (2007). Risk of Transmission of Airborne Infection during Train Commute Based on Mathematical Model. Environmental Health and Preventive Medicine. 12 (2007), 78–83.

5.Brankston G, Gitterman L, Hirji Z, Lemieux C, Gardam M (April 2007). “Transmission of influenza A in human beings”. Lancet Infect Dis 7 (4): 257–65.

6.Conly J, Johnston B (January 2007).

“Is mumps making a comeback?”

. Can J Infect Dis Med Microbiol 18 (1): 7–9

7.EPA. (2012). IAQ Building Education and Assessment Model (I-BEAM).Available: http://www.epa.gov/iaq/largebldgs/i-beam/text/fundamentals_of_iaq.html. Last accessed 04 May 2013.

8.Zhang Tianwei, Liu Shushen, Liu Fang. (2008). Tianjin subway air quality investigation and analysis. Available: http://cpfd.cnki.com.cn/Article/CPFDTOTAL-ZGZM200811003037.htm. Last accessed 04 May 2013.

9.Gustavo Silveira Graudenz. (2011). Chapter 18 Building Related Illnesses. In: Sabah A. Abdul-Wahab Sick building syndrome in public buildings and workplaces. USA: Springer. 341-352.

10.Yang Weichao, Peng Limin. (2009). Analysis of dynamic evolution characteristics on air quality inside subway. Journal of Railway Science and Engneer. 6 (6), 54-55.