Saturday, March 21, 2020

10 Myths and Misconceptions About Bedbugs

10 Myths and Misconceptions About Bedbugs There are many misconceptions about the humble bedbug. Bedbugs (or cimicids) belong to a highly specialized family of insects that feed off the blood of humans, bats, and birds. The best-known members are the temperate-climate parasite Cimex lectularius (which means bedbug in Latin) and Cimex hemipterus, a tropical version. Bedbugs are the most widely recognized insect in the world. They are known to have fed on humans for more than 4,000 years- and probably much longer. Unfortunately, there are many myths about these tiny pests. If You Wake Up With Insect Bites, You Have Bedbugs Bedbugs tend to bite on locations that are exposed during sleep- the arms, legs, and back as well as the face and eyes. The insects prefer sites that lack hair, with a thin epidermis that provides access to plentiful blood. However, bedbugs are not the only nocturnal feeder on humans. Quite a few other arthropods could be the cause of bite marks, including fleas, mites, spiders, or even bat bugs. Also, many medical conditions cause rashes that look similar to bug bites. If the marks persist but you dont find signs of an infestation, consider a trip to the doctor. Are you the only one in your household waking up with bites? People react to bedbug bites differently, just as they do with mosquito and other insect bites. Two people can sleep on the same bedbug-infested mattress, and one will wake up without any signs of being bitten while the other will be covered in bite marks. Bedbugs Cannot Be Seen by the Naked Eye While bedbugs are pretty small insects, they arent microscopic. If you know where to look for them, you can definitely see them without the aid of a magnifier. The bedbug nymph is roughly the size of a poppy seed. Adults measure a bit larger than 1/8th of an inch, or about the size of an apple seed or a lentil. The eggs, which are just the size of a pinhead, are harder to see without magnification. Bedbug Infestations Are Rare Although bedbugs all but disappeared in developed countries in the 1930s and again in the 1980s, global bedbug infestations are increasing in the 21st century. Rises in bedbug activity have been seen on every continent except Antarctica. In the United States, bedbugs are reported in all 50 states, and an estimated one in five Americans either has had a bedbug infestation in their home or knows someone who has. Today, infestations are found in offices and retail environments, in health and transportation buildings, and even in movie houses: basically, anywhere people sleep or sit. Bedbugs Are a Sign of a Dirty House Although there is a great social stigma to having a bedbug infestation, bedbugs dont care how neat and tidy your house is, nor do they care if youre the best housekeeper on the block. As long as you have blood pumping through your veins, bedbugs will happily take up residence in your home. The same rule holds true for hotels and resorts. Whether a hotel has bedbugs has nothing to do with how clean or dirty the establishment is. Even a five-star resort can host bedbugs. One thing to keep in mind, however, is that clutter can make it much more difficult to get rid of bedbugs once theyre in your home- the mess gives the insects plenty of places to hide. Bedbugs Only Bite After Dark While bedbugs prefer to do their dirty work under cover of darkness, the light wont stop a hungry bedbug from biting you. In desperation, some people will try leaving all their lights on at night, hoping the bedbugs will stay hidden like cockroaches. All this will do is make you more sleep-deprived. Bedbugs spend most of their time hidden away. They only come out to feed once every three to seven days, usually from one to five a.m. They fully engorge themselves on your blood in 10 to 20 minutes, and then they go back to their hiding places to digest their food. After a meal, adult bedbugs may increase in length by 30 to 50 percent and in weight by 150 to 200 percent. Bedbugs Live in Mattresses Bedbugs do hide in the seams and crevices of your mattress. Since these nocturnal insects feed on your blood, it is to their advantage to live close to the place where you spend the night. But that doesnt mean bedbugs only live in mattresses. The insects also inhabit carpets and couches, dressers and closets, and even places where youd never think to look, such as inside picture frames and switch plate covers. Infestations can be extremely costly, resulting in multimillion-dollar damage in the hospitality industry, poultry industry, and private and communal households. Costs include payment for pest control, damage to social reputation, and replacement of infested clothing and furniture. You Can Feel a Bedbug Bite Bedbug saliva contains a substance that serves as a mild anesthetic, so when one bites you, it actually does you the favor of numbing your skin first. Its very unlikely that youd ever feel a bedbug bite when it happens. Reactions to bites vary from individual to individual. Some people have no reactions at all; often the bites start out as small indistinct lesions about two-tenths of an inch in diameter, which may develop into larger circular or ovoid welts. Some may grow as big as 2.5 inches in diameter. If there are a large number of bites, they can give the appearance of a generalized rash. They itch intensely, cause sleep deprivation, and can be associated with secondary bacterial infections as a consequence of scratching. Bedbugs Jump From the Floor to Your Bed Bedbugs arent built  for jumping. They simply dont have the legs for it as fleas and grasshoppers do. Bedbugs dont have wings, either, so they cant fly. They can only crawl for locomotion, so moving from the floor to the bed requires them to climb up a leg of the bed, or to scale belongings or furniture youve placed nearby. This can work to your advantage if youre battling bedbugs, as you can create barriers to keep them from climbing onto your bed. Cover the bed legs in double-sided tape, or place them in trays of water. Of course, if your bedspread touches the floor, the bedbugs will still be able to climb up, and the insects have also been known to crawl up the wall to the ceiling and then drop onto the bed. Bedbugs Transmit Diseases to People Although bedbugs can and do carry infectious diseases, there is little danger of the viruses being transmitted to humans. So far, scientists have found no evidence that bedbugs are capable of transmitting diseases to human hosts. For this reason, theyre considered a nuisance pest rather than a health threat. But even though they dont transmit diseases, bedbugs arent harmless. Some people experience severe allergic reactions to bedbug bites, and people who are bitten sometimes suffer from secondary infections. The emotional stress of dealing with a persistent bedbug infestation can also have a negative impact on your health. Bedbugs Can Survive a Year Without a Meal Technically, this is true. Under the right conditions, bedbugs have been known to survive as long as a year without a meal. Bedbugs, like all insects, are cold-blooded, so when temperatures drop, their body temperatures decrease. If it gets cold enough, bedbug metabolism will slow down, and theyll stop eating temporarily. However, it is highly unlikely that it would ever get cold enough in your home to trigger such a long period of inactivity. For practical purposes, then, this statement is false. At normal room temperature, a bedbug might go as long as two to three months without a meal, but thats about it.

Thursday, March 5, 2020

The Many Economic Applications of Shadow Price

The Many Economic Applications of Shadow Price In the strictest sense, a shadow price is any price that is not a market price. A price that is not based on actual market exchanges must then be calculated or mathematically derived from otherwise indirect data. Shadow prices can be derived for anything from a resource to a good or service. But this is just the tip of the iceberg. While economists tend to be committed to markets as a means of valuation, the lack of a market price is not necessarily a limitation of their research. In fact, economists recognize â€Å"goods† that carry societal value for which there are no markets to set a market price. Such goods might include the intangible like clean air. Conversely, economists also recognize that there exist goods that do have a market-traded value that is simply not a good representation of the good’s true societal value. For example, electricity produced from coal carries a market price that does not consider the impact or â€Å"social cost† of coal burning on the environment. It is in these scenarios that economists find it difficult to work, which is why the discipline relies on the calculation of shadow prices to give a â€Å"price-like† value to otherwise unpriced resources. The Many Definitions of Shadow Price While the most basic understanding of the term shadow price relates simply to the lack of a market price for some resource, good, or service, the meanings of the term as derived from its real-world uses relay a more complicated story. In the world of investments, shadow price can refer to the actual market values of a money market fund, which essentially refers to securities that are accounted for based on amortized cost rather than a value assigned by the market. This definition carries less weight in the world of economics. More relevant to the study of economics, another definition of shadow price denotes it as a proxy value of a good or intangible asset that is most often defined by what must be given up to gain an extra unit of the good or asset. Last, but not least, shadow prices can also be utilized to derive an inclusive value of the impact of a project, whether it be a benefit or costs, using stated preferences, making the process an extremely subjective one. In the study of economics, shadow prices are most often used in cost-benefit analyses in which some elements or variables cannot be otherwise quantified by a market price. In order to fully analyze the situation, each variable must be assigned a value, but it is important to note that the calculation of shadow prices in this context is an inexact science. Technical Explanations of Shadow Price in Economics In the context of a maximization problem with a constraint (or constrained optimization), the shadow price on the constraint is the amount that the objective function of the maximization would increase by if the constraint were relaxed by one unit. In other words, the shadow price is the marginal utility of relaxing the constant or conversely, the marginal cost of strengthening the constraint. In its most formal mathematical optimization setting, the shadow price is the value of a Lagrange multiplier at the optimal solution.