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{{Image|Muncprotein.jpg|right|175px|Inman M ( ) Shape of a common protein module suggests role as molecular switch.}}
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'''[[Macromolecular chemistry]]''' is the study of the physical, biological and chemical structure, properties, composition, and reaction mechanisms of [[macromolecules]]. A macromolecule is a molecule that consists of one or more types of repeated 'building blocks'. The building blocks are called  [[Monomer|monomeric unit]]s (monomers).
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==Footnotes==
Macromolecules (also known as polymer molecules) appear in daily life in the form of [[plastic]], [[styrofoam]], [[nylon]], etc. These [[polymer]]s, i.e., substances consisting of polymer molecules, are of great technological importance and are used in the manufacturing of all sorts of goods, from automobile parts to household appliances. The artificial polymer molecules usually exist of long repetitions of identical monomers, either in chains or networks. 
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In molecular biology macromolecules (biopolymers) play a very important role: the well-known molecules [[DNA]], [[RNA]], and [[polypeptides]] ([[proteins]]) are examples of macromolecules. In molecular biology one is mostly interested in  macromolecules in solution, usually dissolved in water.  The biological function  of macromolecules in living cells is  a highly relevant and widely studied topic of research. Although, strictly speaking, biopolymers belong to the class of polymer molecules, there is a tendency not to use the latter name in biological applications, but to speak of macromolecules. The term "polymer"  is usually reserved  for the substances  manufactured in bulk by the chemical industry. 
 
In industry, the value of synthetic macromolecules as plastics and nylon, has risen enormously over the last 60 years. They have made it possible to mould shapes that would have been impossible to create without them. When they were first developed, their resistance to rupture and degradation was seen as a profound advantage, but nowadays we seek more biologically degradable plastics such as polyethyleneglycol that pollute the environment less.
 
Biological macromolecules include, besides the molecules already mentioned, [[enzyme]]s, and [[polysaccharide]]s, such as cellulose and starch. The better understanding  of the basic behavior of polymer molecules has enhanced our knowledge of these biological molecules, and studies of partially charged [[polyelectrolytes]] have led to a deeper insight into their biological function. The investigations of the three-dimensional structure of macromolecules, (their [[configuration]] and [[conformation]]), have led to the identification of specific regions that perform specialized activities. A good example is the catalytic role of particular amino acid residues in polypeptide enzymes and the role of [[functional group]]s such as [[biotin]] or [[riboflavin]] in cellular metabolism. The folding of macromolecules is now a topic of much scientific investigation, since the correct folding of these polymers is a critical factor for normal function. Abnormal folding of particular proteins is the cause of several diseases, including [[Alzheimer disease|Alzheimer's]] and [[Creutzfeldt-Jakob disease]] (CJD) .

Latest revision as of 10:19, 11 September 2020

Categories of smart home devices shown on Amazon's website in April 2023.

The phrase smart home refers to home automation devices that have internet access. Home automation, a broader category, includes any device that can be monitored or controlled via wireless radio signals, not just those having internet access. Whether the device is powered by the electrical grid or by battery, if it uses the home Wi-Fi network and if an internet logon needs to be created to use it, then it is smart home technology.

Collectively, all the smart home devices on every home's Wi-Fi network helps to make up what is called the Internet of Things (IoT), a huge sea of sensors and control devices across the world that are capable of being accessed from afar via the internet. One of the key reasons such devices need internet access is so that the manufacturer can periodically download updated firmware to the device to keep it up-to-date. However, being available via the internet also means that such devices are, potentially, available for spying or hacking. Today, homes may contain dozens or even hundreds of such devices, and consumers may enjoy their benefits while knowing little about how they work, or even realizing that they are present.

Not all home automation is "smart"

Many remotely controllable devices do not require internet access. They may instead have physical control devices that use either RF (“Radio Frequency”) or IR (“Infrared”) beams, two different kinds of energy used in remote controls to communicate commands. Non-"smart" home automation may also present security risks, because the control signals can be hijacked by bad actors with the right signaling equipment. Garage door openers are of particular note in this regard. Modern automobiles, in fact, are full of automation similar to home automation, and cars are hackable by bad actors in a number of ways. See Wikipedia's Automotive hacking article for more information.

Incompatibility hassles

At present, consumers must make sure that the smart device they wish to use is specified to be compatible whichever phone/tablet operating system they use (Apple vs. Android). Since smart home products emerged in the absence of any standard, a morass of competing methods for networking, control and monitoring now exist. For some products, consumers may need to buy an expensive hub, or bridge, a device that is specific to one vendor. Products made by different manufacturers but performing the same function are typically not interoperable. Consumers often need to open a different app on their smartphone or tablet in order to control devices by each manufacturer. This may make it too expensive and awkward to try out competing devices, leaving consumers stuck with the product they bought originally or else having to add yet more apps to their phones.

Security concerns

Security for smart home products has been uneven and sometimes seriously inadequate. Smart thermostats which can monitor whether a home's occupants are present or not, entry-way locks, robotic vacuums that work with a map of the house, and other smart home devices can present very real dangers if hackers can access their data.

Matter, an emerging standard

Matter is emerging standard in 2023 intended to increase security, reliability and inter-operability of smart-home devices. About ten years ago, industry consortiums formed to work on standards for smart home device communications, and their underlying wireless communications, which would make it possible for products from all vendors to work together seamlessly and provide fast performance, privacy, and security and would work even if there is not connection to the outside internet (i.e., no connection to "the cloud" or to servers).

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