Ubuntu wireless/WiFi connection does not work

Ubuntu is a very popular Linux operating system which has many functions that are equivalent to those provided by Windows, such as web browsing, playing music and videos, and support for office applications like writing letters and spreadsheets.  Ubuntu and several other Linux operating systems are free to use, so they can give new life to old computers.  Now that it is possible to get a new laptop for less than $300 dollars, it does not make economic sense to take for repair a laptop with a crashed hard drive and then spend about $200 dollars more to buy a Microsoft Windows operating system and Microsoft Office.  The cost of the repair plus the software will exceed the cost of a brand new computer, but it would be a shame to throw away such a piece of technology if it can be reconditioned cheaply.  The smart thing to do is to replace the hard drive by yourself and install a free Linux operating system that will perform all the functions of the old computer.

This is exactly what I did with a Sony VAIO computer with a crashed hard drive.  Ubuntu 14.04 installed without any problems and I was able to network the VAIO computer with a Windows computer using a wired Ethernet Local Area Network (LAN).  However, when I disconnected the Ethernet cable and tried to connect to the network wirelessly, Ubuntu could see the WiFi access point, but it could not connect.  I went through the Ubuntu Wireless Troubleshooting Guide, but none of the suggestions worked.

Finally, I came across a blog where one user said that he had solved this problem by using a USB wireless adapter.  I happened to have such an adapter that I had used on a Windows 95 computer a long time ago.  I plugged it into the USB port of the Ubuntu machine, and lo and behold, the connection worked, but only at 54Mbps which was the rate limit of the old wireless adapter.  I went back into the Ubuntu wireless configuration panel to see what the difference was between the USB wireless connection that worked and the one of the built-in wireless connection that did not work.  I copied the configuration, and everything worked fine, but at a higher speed.  Below is the configuration that worked for me.  The Ubuntu installation had originally set the WEP index to 2 and I had to change it to 1.   It was a simple change, but it was crucial.

Cuban Cigar Diplomacy

Cohiba Cuban Cigars

President Obama announced on December 17, 2014 that he would pursue full diplomatic relations with Cuba. The new policy is basically an admission that the attempt to isolate Cuba in the hope that the Cuban people would rise against Castro’s regime has failed. A new policy of engagement with the Cuban people will probably be much better for the U.S. and for Cuba, just like Nixon’s policy of engagement with China led to improved commerce, better international relations and the end of the cold war.

Cuba was a popular destination for U.S. tourists before Castro’s revolution. Ernest Hemingway wrote his Pulitzer Prize winning novel “The Old Man and the Sea” while living in Cuba. Cuban products, such as sugar, cigars and rum could be found in many American homes. The U.S. embargo changed all that and caused Cuba to seek economic relief and military aid from the Soviet Union. Following the failed Bay of Pigs invasion in 1961 by the U.S., Cuba requested nuclear arms from the Soviet Union that eventually resulted in the Cuban missile crisis in October 1962.

The renewal of diplomatic relations between the U.S. and Cuba will have many ramifications. Tourism and commerce will certainly flourish, but it will also be necessary to re-establish trademark protections that were not respected during the 54 years of enmity that started with the U.S. embargo of 19 October 1960. One of the tasks for improving diplomatic relations will be the restoration of the Cohiba brand name for marketing of Cuban cigars.

Could methane be stored as a clathrate on Mars?

The first definitive detection of methane gas on Mars was reported in 2009[1]. The atmosphere of Mars is highly oxidized, consisting mainly of carbon dioxide gas (95%). With a photochemical lifetime of only 400 years, methane should not be present unless it was released on an ongoing basis. On Earth, about 95% of the methane is produced by biological organisms and the rest is produced by geochemistry. The presence of methane on Mars demonstrates that Mars is an active planet which is actively releasing trace gases that provide a window into its internal processes.

The release of methane on Mars suggests that Mars might now harbor an active microbial life below the surface, but it is also possible that the release of methane is driven by chemical reactions of hot rock with water and carbon dioxide deep underground. The seasonal release of methane suggests thermal control of the release mechanism.

A possibility that thus far has not been considered is that methane can be trapped within the crystal structure of water to form methane clathrate which on the Earth is found in permafrost and at the bottom of the ocean. The phase diagram of methane clathrate[2] shows that it may be possible that methane clathrate would be stable in the Martian environment with an atmospheric pressure of 600 Pa and temperatures averaging 218 K at the surface. Underground, the pressure would be higher making the formation of methane clathrate more likely.

Although scientists are very eager to find some kind of life on Mars, the seasonal variation of atmospheric methane could just be due to the decomposition and regeneration of methane clathrate, or some other physical or chemical process. Let us not forget that Titan, one of Saturn’s moons, has lakes of liquid methane on its surface. Jumping to the conclusion that the presence of methane indicates life is not good science. Proof of life will have to come from biology, and not necessarily from chemistry.

Learn about Earth’s atmosphere

[1] Mumma, MJ; Villanueva, GL; Novak, RE; Hewagama, T; Bonev, BP; DiSanti, MA; Mandell, AM; Smith, MD, Strong release of methane on Mars in northern summer 2003, Science, Volume: 323, Issue: 5917, Page: 1041-1045, Year: FEB 20 2009

[2] Laura A. Stern, Stephen H. Kirby, William B. Durham, Peculiarities of Methane Clathrate Hydrate Formation and Solid-State Deformation, Including Possible Superheating of Water Ice, Science, 27 September 1996, Vol. 273 no. 5283 pp. 1843-1848
DOI: 10.1126/science.273.5283.1843

Neandertals among us

Neandertals lived in Europe and Asia from about 250,000 to 30,000 years ago.  They had bigger brains than modern humans, but they never advanced technically beyond the stone age.  Not too many years ago, archeologists and paleoanthropologists thought that modern humans had outcompeted the Neandertals and caused their demise.

Advances in analysis of ancient DNA and genetic testing have revealed that the Neandertals did not just disappear.  They mated with modern humans when they met in Europe thousands of years ago and produced offspring with genes from both species.  Modern humans of non-African origin have up to 3% Neandertal DNA.  The people with the greatest concentration of Neandertal DNA are found in the region of Tuscany, Italy.

The story of human evolution is becoming clearer with the use of genetic testing.  A tiny bone found in Denisova Cave in the Altai Mountains of Siberia provided DNA of previously unknown people which were different from Neandertals and modern humans.  It turned out that these Denisovan people actually contributed 3% to 5% of their DNA to modern Melanesians and Australian Aborigines.  The importance of the tiny bone would not have been recognized without genetic testing of its DNA.

Learn more about Human Evolution

Solitaire Game in JavaScript

Computer hacking has increased in recent years.  Criminals can profit from the personal and financial information stolen from the victims they have hacked.  In some cases, weaknesses in Java Applets have been exploited to infect computers with malware.  Web browsers now warn users of the potential risk.  The following discussion describes the differences between Java, Java Applets and JavaScript.

Java is a general programming language that can run on Windows, Linux or Mac computers regardless of computer architecture.  This versatility is accomplished by converting the Java computer programs into bytecodes that are interpreted by a virtual machine.  The Java Virtual Machine (JVM) is a computer program tailored for the specific hardware and operating-system platform.  When you download Java software, the package contains the JVM and Java Plug-in software that enables browsers to execute Java Applets.

A Java Applet is a small application written in the Java language and stored as bytecodes.  When a browser encounters a web page containing a Java Applet, the browser uses the Java Plug-in to decode the instructions indicated by the applet.  The result is usually an interactive web page that the user can use to play a game or perform calculations.  Weaknesses in the web browsers can be exploited by malicious Java applets, and for this reason some mobile browsers do not run Java applets at all, or they issue a security warning that asks for confirmation before allowing Java applets to be executed.  The warnings may discourage users from using particular web pages even when they pose no danger. It is possible that in the future, browsers will not run Java Applets at all.

JavaScript is an interpreted computer programming language that is used by web browsers to interact with the user and control the display of the web page. Except for a similarity in the name, JavaScript is not related to the Java programming language.  Although JavaScript can have some security problems, it does not have the vulnerabilities of Java Plug-ins.  The use of JavaScript is now ubiquitous in many web applications such as Gmail and Google Maps that use Ajax (Asynchronous JavaScript and XML).  The following links let you compare the implementation of a FreeCell Solitaire game implemented as a Java Applet and as a JavaScript application.

FreeCell Solitaire Java Applet

FreeCell Solitaire in JavaScript

Six foods that you should eat every week

Fast food and frozen dinners have become a large part of the modern diet, mostly because of convenience.  Poor food choices that include sugary drinks and greasy snacks contribute to the high incidence of obesity, particularly when combined with a sedentary life style.

Eating small portions will help you maintain a healthy weight, but when you eat less your diet must include all the essential vitamins and minerals for proper nutrition.  Here are six foods that eaten every week can help you to stay healthy.

1. Nonfat yogurt is source of protein and calcium as well as probiotic bacteria that keep disease-causing bacteria from getting established in the digestive system.

2. Sardines contain protein and essential minerals, but they are also a source of omega-3 fatty acids which are essential for the health of the brain and the eyes.  These long-chain polyunsaturated fatty acids are particularly important nutrients during pregnancy and early childhood.  Unlike larger long-lived fish like tuna and swordfish, sardines have a lower content of heavy metals like mercury because they are lower in the food chain.

3. Oatmeal is a source of soluble fiber that lowers cholesterol and promotes regularity.  Fiber is not a nutrient, but it helps to attenuate blood glucose spikes by reducing the absorption in the intestines.  In addition, fiber promotes growth of intestinal bacteria that produce short-chain fatty acids and Vitamin K.

4. Salad greens contain a wide variety of vitamins, phytonutrients and fiber.  Leafy greens contain Vitamin E, Vitamin C, beta-carotene, lycopene, lutein-zeaxanthin and many other chemical compounds essential for good health.

5. Berries are a good source of anthocyanin antioxidants and vitamins.

6. Nuts contain omega-3 and omega-6 fatty acids, as well as protein and fiber.  Nuts are generally high in calories due to their oil content, but these are good fats.  If you eat peanut butter or other nut butters, make sure that they do not contain hydrogenated oils or saturated fats like coconut oil or palm oil because these increase cholesterol levels.  Read the labels.

These six nutritious foods can be combined into delicious meals.  A bowl of oatmeal can be garnished with berries and nuts topped with a spoonful of yogurt.  Sardines served on a bed of mixed salad greens will also make an excellent meal.

Use the Diet Calculator

Carolina Bays formed from slow-speed glacier ice impacts

According to a recent theory, during an ice age, 12,900 years ago, a meteorite or comet struck the massive glaciers that covered the Great Lakes region.  The catastrophe caused the extinction of the saber tooth tigers and other large animals that lived in North America at that time.  Thus far, no meteorite fragments from such an impact have been found.  The formation of the Carolina Bays has been claimed to be one consequence of the extraterrestrial impact.  A meteorite strike on the Laurentide ice sheet would have sent enormous ice boulders from the glaciers, many as big as two football fields, all the way from central Michigan to the Carolinas and Georgia.  The impacts of the huge chunks of ice formed shallow craters that became the Carolina Bays.

A new impact model solves the mystery of why almost all the Carolina Bays are perfect ellipses by interpreting them as conic sections.  The oblique impacts created tilted conical cavities which at the intersection with the level surface of the Earth are conic sections that appear as elliptical craters.  The ice boulders had velocities of 3 to 3.6 kilometers per second, which is much slower than the 17 kilometers per second for asteroids or 50 kilometers per second for comets.  Impacts at the slower speeds would create shallow oval craters. The craters would be deeper at the terminal end due to the inclined incidence of the impact. The craters would also have raised rims, particularly at the terminal end of the ellipse.  When the glacier ice impactors melted, the melt water created pools in the depressions.  Most of the oval pools eventually filled by silting and viscous relaxation of the ground to produce the Carolina Bays.

Geologists have refused to accept Carolina Bays as impact sites because the target zones do not exhibit signs of shock metamorphism created by high velocity impacts and no meteorite fragments or chemical elements from meteorites have been found.  The new impact model states that the slow speed of the glacier ice impacts would not produce shock metamorphism, and because the glacier ice is of terrestrial origin, there would be no traces of meteorites or sidereal chemical elements. However, the model predicts the location where it might be possible to find stones that were originally embedded in the glacier ice.

Read more about the Carolina Bays

The Rise of the Transgenic Queen

The Rise of the Transgenic Queen by Antonio Zamora is now available for Kindle devices.

The story depicts the evolution of mankind after a genetic experiment gets out of control. The directors of a new genetic engineering firm seek to make large profits from a new type of diet therapy. The brief escape of one of the laboratory animals causes Ludmila, one of the female scientists, to accidentally become infected with a virus vector carrying hymenoptera genetic material from a small gene therapy research project. The physical changes from the expression of the genetic modification have unforeseen consequences that transform Ludmila into the Transgenic Queen, thus altering the biological evolution of mankind.

Marijuana reduces Intelligence Quotient in adolescents

The opium poppy and marijuana have been used for millennia in traditional medicines for the relief of pain and serious illnesses. However, their potential for addiction and the social problems that they cause has led to government regulations that make the possession of these herbal products illegal.  Morphine, which is generally 8 to 14 percent of the dry weight of opium, is a powerful analgesic that is used in modern hospitals to control pain for dying patients and for patients with serious injuries.

Marijuana, a variety of hemp plant, has had a more difficult transition into the modern medicine chest because it is often abused as a recreational drug.  The active components of marijuana are called cannabinoids.  Hashish is produced from Cannabis indica plants that are traditionally cultivated in India, Afghanistan, Bangladesh and Pakistan.  Cannabidiol (CBD) is a main psychoactive component of hashish.  Marijuana is produced from Cannabis sativa and its main active component is tetrahydrocannabinol (THC).


Tetrahydrocannabinol

Medical cannabis has been documented as an effective treatment for nausea, vomiting, neurogenic pain, glaucoma, and many other conditions.  Cannabidiol has also been found effective at stopping breast cancer from spreading throughout the body.  Several states, like Colorado and Washington, have legalized the purchase and possession of marijuana, but it is still banned under the federal Controlled Substances Act.

Approximately 1100 metric tons of marijuana are smuggled each year from Mexico to supply the recreational drug market, and large quantities are also grown within the United States.  Young people often believe that regular marijuana use is not harmful, and many high school age students use cannabis on a daily basis.  A study at Duke University[1] followed 1037 individuals from age 13, before initiation of cannabis use, to age 38.  Neurophsychological testing found that persistent cannabis use was associated with a broad decline in cognitive function.  Impairment was concentrated among adolescent-onset cannabis users, with more persistent use associated with greater decline. The changes were permanent.  Cessation of cannabis use did not fully restore neuropsychological functioning among adolescent-onset cannabis users.

Learn more about drug addiction

[1] Madeline H. Meier, et al., Persistent cannabis users show neuropsychological decline from childhood to midlife, PNAS, October 2, 2012, (109) 40, E2657–E2664, doi: 10.1073/pnas.1206820109

 

Right arm hurts when coughing

I was recovering from the flu and the only remaining symptom was a stuffy and runny nose.  I thought that I was already on my way to recovery when I became aware of a combination of a dull pain and numbness in my right arm.  When I coughed, I could feel a shooting pain in my arm.  Over the next two days, the pain got worse and I could not find a comfortable position to sleep without feeling the pain in my arm.

I am not one to run to the doctor for every little pain.  With experience, I have learned that doctors will drug you so that you don’t feel the pain, but the real diagnosis could take a long time after many visits and tests.  For something that is not life-threatening, my first instinct is to search the Internet to find out what the problem could be.

My search found that the problem might be a herniated disk, a blood clot, lung cancer or other equally serious conditions.  Since my pain had just started recently, and I did not have any pain in my neck or neck movement, it was unlikely to be a problem related to the spine.  My arm was still strong but the muscle of my forearm felt a dull pain.  I decided to be though and wait at least one more day before going to the doctor.

I spent another night trying to find a comfortable position for sleeping.  At this time, I noticed that I had a muscular pain just below my right scapula.  I pressed my fingers on the spot and felt some tenderness.  Aha!  I suddenly remembered what I had done the day before the pain started.  I had helped my wife weigh her luggage on a bathroom scale.  Since the scale was not big enough to hold the luggage, I weighed myself holding the luggage and then subtracted my weight.  I remembered straining while trying to balance my weight as I held the luggage.  I did not have a blood clot or cancer after all.  It was a simple strain.

I decided not to go to the doctor.  Many years before, while walking my dog, I had suddenly felt a back pain that had sent me to the emergency room.  The doctor gave me a pain killer that made me giddy and then asked me if I knew what was wrong with me.  I said, “No,” and he replied, “I don’t know either.  Back pains are very common and they generally go away after a week or two.”  On that occasion, I spent a week in bed and the back pain was most severe when I had to use the bathroom.

The back has many muscle fibers that extend from the spine to the hips, ribs and scapula.  During your lifetime, some of these muscle fibers will tear and give you great pain, although not necessarily right away.  Seek medical attention, but be aware that even modern doctors cannot heal your back; they can only numb the pain.  My advice is: Don’t lift heavy luggage!

Exercise regularly and in moderation