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Getting deconfined at the right pace

Resulting from the confinement of the last couple of months, some might feel that they pushed the sedentary lifestyle up to the point where they now feel the need to get back into shape as soon as possible. Whatever the privileged activity is, the golden rule requires to put back on track our “machine” at a progressive rate. Whether for the beginner or for those recovering from an injury, a progressive interval-based program, alternating walking and running will achieve the wildest goals while minimizing the risk of injuries. The book Prevention of running injuries (1) offers, among other things, an interval program which begins on “Day One” with an alternating outing between three minutes of walking and three minutes of running. This same program will lead the runner to run thirty continuous minutes after eight weeks of gradual and assiduous progress. We all have specific physical conditions and obviously certain situations could require the
consultation of a health professional.

All the best with your deconfinement!

Rémi Charbonneau, Engineer
Scientific Expert – Mechanical Engineering
Email: rcharbonneau@msei.ca
Cell: 514-475-7364

 

1 Prevention of running injuries: The running clinic, Blaise Dubois, 2010

Getting deconfined at the right pace2020-06-17T17:39:34+00:00

Polarized glasses: How do they work?

By David Rousseau, Chemist, M.Sc.

Visible light is a wave, just like microwaves, X-rays, UV rays and radio waves. They are called electromagnetic waves and are generally represented as a sinusoid, similar to a jumping rope that is waved. Contrary to the other kinds of electromagnetic waves, light can be very effectively processed by our brain. This little bandwidth is extremely well interpreted by our brain and produces a physical representation: sight.

For the other kinds of waves, material support or equipment are required to permit their visualization. The best examples are radiography and thermography.

Thermography
(infrared visualization)

Radiography
(X-ray visualization)

Sometimes, our brain’s capacity to treat light results in too much information. In some cases, less light is preferable for a more efficient information treatment. Therefore, in an effort to lower the amount of information entering our brain, we instinctively squint our eyes or wear sunglasses, for example. Today, we can even completely eliminate certain stray light information by wearing polarized glasses, which in turn greatly enhance our sight comfort.

Without polarized glasses

With polarized glasses

What is polarization?

What is parasitic light information?

Polarization

Natural sunlight is depolarized which means that the light rays that reach us do not have a specific orientation. Going back to our example of the waving skipping rope, we can represent the light waves as follows:

We see here four (4) light waves of the same amplitude and frequency, going in the same direction, but without any privileged orientation, just as if we were to wave the rope in different orientations (up to down, left to right or diagonally). This is called an unpolarized light wave.

“Unpolarized” is the term used to mean “without any privileged orientation.” If we position ourselves in the axis of these light waves, we see them point in different directions.

The above right drawing shows four (4) waves among the infinite number of waves reaching us from all possible orientations. Therefore, an unpolarized sunray is represented like this:

All these waves form an unpolarized light ray.

Parasitic Light Information

Parasitic light information can be defined as radiance reflecting on an object that doesn’t give any information such as colour, texture or shape about it. This light, which is entirely reflected by the surface, like a mirror, parasites the useful information about the objects.

When this light is reflected on a horizontal surface (such as water, roads or snow on ski slopes), it becomes naturally polarized within a privileged axis: the horizontal axis.

This therefore results in a huge quantity of information reflected in this axis, causing a bright glare.

At a precise angle (Brewster’s angle), which primarily depends on the surface the light is reflected on, the light is reflected at 100% on the horizontal axis, causing a maximum glare. This happens on the sea or the road when the sun is relatively low in the sky, because an angle of approximately 30° is needed to reach the maximum effect. But this phenomenon is more pronounced in the mountains and can happen at any time of the day, because the surfaces being reflected are abrupt, bearing variable angles.

Standard, unpolarized sunglasses will attenuate the amount of global light that reaches us, but without “targeting” the reflected parasitic rays. Therefore, parasitic light remains an important and significant proportion and continues to mask pertinent information needed by our brain.

Polarized sunglasses, on the other hand, are designed to allow only polarized light to pass through in the vertical direction (↨) and they will therefore completely block this parasitic information.

The polarized glasses are always polarized in the vertical direction (↨), because it is the parasitic reflections coming from horizontal surfaces which are the most disturbing in the vast majority of the cases (surface of the water in a boat or surface of the road in a car).

If you are an amateur photographer, you already know polarized filters mounted on cameras are rotative. The reason is that it is imperative that the filter angle be adjusted to keep the polarization in the desired axis (↨) in order to take pictures in different positions.

Or cut the reflection (parasitic light) of a non-horizontal surface, like a window for example, and making it possible to photograph through it.

This effect of natural reflection of light on the windows gives a certain intimacy at the residential level but poses problems at the commercial level. Polarized filters are also installed on certain store windows to avoid this type of reflection and thus allow passers-by to clearly see the displays inside the stores at any time of the day.

Science is everywhere!

You may also have noticed that some screens appear black when viewed with polarized glasses. This is because these screens emit polarized light that is exactly 90° from the polarization angle of your glasses. A mechanism occurs that is identical to that of polarized light reflected from the surface of the water, but this time the effect is undesirable.

Fortunately, the majority of screens, namely those found in cars, emit polarized light at an angle that permits them to be readable with sunglasses.
The next time that you are wearing your sunglasses in the car, simply turn your head to determine what is the polarization angle of your screen.
There it is! Polarization bears no more secrets for you … almost!

For any further questions, do not hesitate to contact your specialist:

David Rousseau, Chemist, M.Sc.
Scientific Expert – Senior Project Manager Email: drousseau@msei.ca
Phone: 514-679-2058

Polarized glasses: How do they work?2020-06-25T18:05:03+00:00

Coronavirus (COVID-19)

To all our customers,
Concerns in Quebec and in Canada regarding the Coronavirus (COVID-19) pandemic are evolving rapidly. MSEI MultiSciences Expertises Inc. (MSEI) wants to make sure, above all, that you and your families are healthy and that you currently benefit from adequate working and living conditions in order to prevent, by all possible means, contamination with COVID-19.
MSEI staff is aware of the processes to prevent the spread of COVID-19 which affects us all today. The offices of MSEI remain open and the continuity of our services is maintained, thanks to our technological choices implemented for the past several years.
To date, MSEI maintains these services and we are able to carry out all of the mandates entrusted to us. To carry out certain of our projects, special precautions will be taken. MSEI’s professionals will confirm with you whether the fulfillment of your mandate remains possible in the current context.
When specific mandates (particularly on-site investigations) call on external resources, MSEI will require that the latter adopt the same directives and protective measures as the ones we are promoting.
At all times, MSEI staff is able to answer your questions and assist you with your mandates.
We are constantly monitoring the situation and we defer to the directives of the competent authorities.

Jean René Dumont
President and General Manager

Coronavirus (COVID-19)2020-03-23T18:40:10+00:00

Why Does the Insurance Company Need a Scientific Expert?

Once in a while, in order to facilitate his work, his understanding as well as to save time, or else corroborate certain decisions during loss management, the insurer or his claims adjuster representative must call upon technical or scientific specialists in different fields of expertise.

The first goal is a better understanding of the dynamic and context of a loss, but also to render better service to the insured. The insurer cannot be an expert in all the fields. Each loss is different and must be managed the right way from the start.

When a loss is even remotely connected to scientific phenomena or in the presence of complex interactions such as found in engineering or environmental files, the expert can provide a scientific opinion regarding a precise question, scientifically demonstrate origins and causes, or still, offer an overall help to resolve the case.

The expert’s responsibility is, among others, to support the insurer in his process to fairly resolve the case and to advise him on ways to finalize it. These means aim to put the insured back to the position he had before the loss, or to answer a direct claim or in responsibility.

The expert’s mission is to provide to his client recommendations drawn from his experience and his scientific knowledge, based on a detailed diagnostic of the situation. Since he is independent from the insurer, his integrity and objectivity are essential. The expert must remain impartial in situations where it would be difficult for the insurer to remain so.

The establishment of the origins and causes on solid scientific bases by the expert is also crucial in subrogation cases, in order to recover the sums of money paid to the insured for a loss caused by the negligence of a third party.

Why Does the Insurance Company Need a Scientific Expert?2020-01-14T16:00:20+00:00

Origin and Causes of Materials Failure and Their Prevention

To be able to answer these questions, which may have legal implications, our team of scientific experts must be aware of engineering principles and knowledge.

The solution to a cause of failure often requires the intervention of several scientific disciplines that MSEI can offer to its clients through its multidisciplinary team. Scientific experts are often excellent generalists because the assessment of the failure must be done by evaluating several aspects, like the pieces of a puzzle. At the beginning of the investigation, only the loss (the outcome) is known. Then, each piece of the puzzle is sequentially analyzed. At first, individual pieces may seem to provide little information. Several points will therefore need to be investigated:

  • What were the conditions in service?
  • Was the maintenance performed adequately and was the inspection schedule followed?
  • When were the last works done and who did them?
  • Were there any problems during the assembly?
  • Were there errors during the production?
  • Was the design adequate?
  • Were the materials used within specifications?
  • Was the heat treatment appropriate?
  • Was the environment in which the part was used problematic?

By analyzing each piece methodically, studying their interrelation with each other and assembling them, the cause of the failure will become clearer, and the ultimate question will be answered. Failure will have been reconstructed by the scientific experts, and the client’s file will move on.

MSEI scientific experts may, inter alia, be required to analyze the causes of failures occurring in industrial, institutional or residential environments as well as the causes of collapsed structures, car accidents, fires and explosions.

Origin and Causes of Materials Failure and Their Prevention2020-01-14T15:59:59+00:00

Summer Thunderstorms: Characteristics and Energy

Summer thunderstorms are often characterized by their intensity and the large quantities of water they produce over a short period of time on a territory. These events may generate floods and significant claims for insurers.

Figures 1 and 2 show typical thunderstorm cells observed in the summer, generally coinciding with hot and humid weather. Such storm cells are characterized by their relatively limited dimensions, and are roughly cylindrical. They comprise three identifiable zones illustrated on figure 3 (Chow et Als. 1988), which consist of an inflow region near the ground, where warm moist air is drawn into the cell (Zone A), an uplift region in the middle, where moisture condenses as the air rises, producing precipitation (Zone B), and an outflow region in the upper atmosphere where outflow of cooler, dryer air occurs (Zone C). Such drier air is circulated back down to the ground, where it contributes to the convective cell air circulation through the bottom of the cloud base.

Figure 1 

Figure 2 

Figure 3

Thicknesses in the order of 8 to 16 km are typical of storm cell cloud covers. Through the analysis of continuity for water vapour and related energy balance (see reference 1), it is possible to calculate that a thunderstorm cell of 5 km in diameter with a cloud cover beginning at an altitude of 1.5 km and terminating at 10 km, with conditions of ground air temperature of 30 oC and atmospheric pressure of 101.3 kPa, can produce a precipitation intensity of 9.8 cm/hour over the ground surface area of the 5 km diameter cell. This represents a volume of 535 m3/second of rainwater flowing onto that territory area.

The condensation of moisture allows the release of its latent heat which, for the volume of water involved in the above calculation, translates into a total energy of 1,335,000 MW. Comparatively, the powers of hydroelectric generating stations Manic 5 and LG2 in Quebec are 2,660 and 5,096 MW respectively. It is therefore obvious that even for a relatively limited sized storm cell, the quantity of the energy released through rain is enormous. One may appreciate the corresponding devastating effects, storm water collection networks often times not being able to manage over a short period of time the quantities of water involved.

It is also typical of flood generating thunderstorms that they occur between weather data stations on a given territory. Under such conditions, the data collected at such stations may not reveal the occurrence of these thunderstorms. Investigations conducted by the insurers following a loss must then resort to collecting data available through the manifestations of these thunderstorms in the field to characterize the event.

Summer Thunderstorms: Characteristics and Energy2020-01-14T15:57:40+00:00

Legionella: Origin and causes of the recent infections

Legionella spp. is a bacterial genre frequently found in aquatic environments such as lakes, rivers and drinking water systems. The Legionella pneumophila, which is the most commonly found species in cases of human infections, has first been involved in an outbreak of pulmonary infections in 1976, among legionnaires attending a convention in Philadelphia.

The Legionella genre comprises more than 50 species. These bacteria develop at temperatures between 25 and 42 degrees Celsius and are usually found in showers, spas, cooling towers and water heaters. They thrive in areas where the temperature is already ideal for other microbes to live and grow. The contamination propagates following the inhalation of contaminated droplets. The elderly, immune-deficient individuals and smokers are the people most at risk of being affected by these bacteria.

In the summer of 2012, the area of Québec City went through an important hatching of Legionella bacteria, to the point where more than thirteen people died. The cooling towers were targeted and disinfected. On the other hand, it is also possible that some water heaters or spas may have caused the sickness in certain individuals. Indeed, as early as the end of the 1990s, a study showed that the water heaters in this region were Legionella carriers in a proportion of about 30%. This fact is also well documented for spas and shower heads. In order to eradicate this problem, a minimum of 0.3 mg/L of free chlorine should be maintained. Maintaining this quantity of chlorine can be achieved, but it is difficult to control in cooling towers and water heaters. Moreover, the chlorine can oxidize the equipment, a drawback administrators tend to fear.

Legionella: Origin and causes of the recent infections2020-01-14T15:53:18+00:00

Agricultural Issues and Pesticides

Each year, MSEI receives numerous mandates pertaining agricultural losses, whether related to loss of crops in the fields or in storage, various animal productions, as well as dairy production.

Within those files, those concerning loss of crops in the fields that are related to pesticide applications are the most complex of them all.

The mechanisms and causes of losses linked to pesticides vary and the scientific expert agronomist is best qualified to resolve these issues which usually involve multiple responsibilities. For instance, the principal causes linked to theses losses, as observed over the years are:

  • Drifts to unintended fields caused by winds during application
  • Poorly cleaned residues in the sprayer from a previous application (cross contamination)
  • Residual side effect due to a previous application
  • Cumulative effects of residues of several products in the soil
  • Wrong dosage or inadequate use of one or a combination of products
  • Cross-contamination transfer of containers or other products manipulations

The determination of the causes is performed by observations in the field, the expertise of data related to the damaged crop and the products concerned and also by targeted laboratory analyses on soil, plants or products used.

Another difficulty of these files is to establish a fair quantum of loss, especially in the case of partial loss. Some losses can sometimes be reduced by revenues of alternative markets for crops, where initial target market is no longer possible.

The experience and general knowledge of the scientific expert play a key role in this kind of file. Such expert will research the best solutions and, in particular, for the production of files necessary to better define the claim.

MSEI’s experts will assist you to achieve this type of case and defend it in court, if necessary.

Agricultural Issues and Pesticides2020-01-14T15:04:06+00:00

Mushrooms, Moulds and Wood Deterioration

It is not uncommon that wood structures deterioration in buildings is attributed to rot following water damages or watering caused by a partial fire. This attribution is usually false because moulds are not the real cause of deep rot in wood.

Moulds are “microcospic” mushrooms, in other words, mushrooms difficult to see with naked eyes. In the presence of favourable humidity and temperature conditions, they grow on the surface of materials and rapidly produce spores. These germs are used for their reproduction and can cause allergic reactions to sensitive persons. When they produce spores (or sporulate), we can see tiny moss of different colours on the materials. Depending on their genus and species, moulds usually grow and die rapidly, but they do not deeply affect the wood.

On the opposite side, mushrooms said to be “macroscopic”, can deeply deteriorate wood. These mushrooms have an easily observable development when they build their wide reproductive structures. However, when they grow in materials, they can stay hidden for months, even years. Edible mushrooms are examples of these, as well as dry rot the “house enemy,” which has already been a topic in one of our bulletins.

It would take lots of months, in the best of conditions, even years, for macroscopic mushrooms to develop, with the help of other microorganisms, and to deteriorate wood structures to the point of their loss of integrity. This is why, if we observe rotten wood structures or that moulds are present a few days or weeks following a loss involving water, these have nothing to do with the deep deterioration observed. They only took advantage of the new opportunity given by the loss.

It is thus important to consult an expert in microbiology, who will be able to distinguish the limits of the losses due to these kinds of cases, compared to the long-term deterioration of the building. For the expert, the deterioration profile will also indicate the possible causes of this deterioration.

Mushrooms, Moulds and Wood Deterioration2020-01-14T15:50:52+00:00

The Scientific Expert’s Impartiality (Part 2)

In our previous bulletin, we mentioned the importance of the independence of the scientific expert in his mandates and, ultimately, during his presence in court. The pertinence of this independence or impartiality is particularly reflected during the expert’s cross-examination by the prosecutor and/or by the judge himself simply because the expert must respond based on his/her own opinion and not with what his attorney wishes to hear.

This is particularly true when the tribunal consists of nine judges who can question the expert at any moment, or indeed, any of the six prosecutors, who are trying to find a “hole” in the testimony, during their cross-examination. It is exactly how the Iran-US claims tribunal in The Hague (Netherlands) is proceeding.

Recently, a MSEI representative had the opportunity and the privilege of being an expert witness before that court for a dispute dating back to 1979, between the Iranians and the Americans. This international tribunal was actually initiated in 1981 following the Algiers’s Accord, in order to resolve over 4,200 disputes originating directly or indirectly from the American-hostage crisis of 1979.

Most of the dispute, for which MSEI was called as an expert witness before the court, was linked to damages caused by weathering of over eight hundred (800) mobile home units (construction site trailers). Specifically, the damage was caused by microorganisms (mould and rot) on construction material and household goods that were packed inside these units.

When called before different courts of justice in North America, many of us have encountered, in one way or another, an expert witness who stretches themselves a little too far or attempts to rewrite science in their own way to the point of giving answers or arguments that others might find perplexing. Even during the Iran-US claims tribunal stated above, we met a few facts and experts witness which could be classified in that category.

Such a situation produces futile arguments between the experts, undermines our credibility and tarnishes this wonderful industry of expertise in which we operate.

MSEI’s experts have accumulated decades of experience as expert witnesses in different courts of justice. They have this credibility and their integrity is without fault. Our clients always know the whole truth regarding the scientific aspect of their case.

The Scientific Expert’s Impartiality (Part 2)2020-01-14T15:49:37+00:00
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