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Comment Single-experience people are arrogant... (Score 1) 823

It's for this reason that I don't hire people who have only done one thing in their life. They tend to believe that their way is the only way; that they know more about whatever I need them to do than I do; that they are a gift to me; that they are irreplaceable.

None of those are usually true.

They need to get out there and experience real people and real life.

I want someone who has tried various majors, someone who has taken philosophy and computer science and physics and photography and history of jazz and has hiked the Appalachian Trail (in reality and in euphemism) and has made their own kite and has attended a political rally and has volunteered at a homeless shelter and has babysat and has restored a classic muscle car and has participated in toastmasters and is training to run a marathon and watches soccer and plays cribbage and...

I don't want someone who spends their days sitting at a computer figuring out how to make ext4 work 0.1% more efficiently. They may know the details of that code, but they'll be useless as an employee.

Comment Re:Partially on the subject... (Score 1) 155

It's not incorrect. It's a simplification.

The Earth has what's called a tidal bulge that is caused by the moon (and the sun). This tidal bulge extends toward and away (180-degrees) from the Moon, though due to various strength and inertial effects and rotation of the Earth, the bulge doesn't actually point directly at the Moon.

What it amounts to is that the moon's gravitational effect on the Earth, averaged over the long term, would not have any significant differential effect on high-mass vs low-mass materials within the Earth's interior.

The sentence you're pointing at particularly was about the tidal flexing of the Earth, which would have some small effect on the Earth's interior energy, causing a slight heating and possibly allowing higher mass materials to move deeper into the Earth's interior.

Comment Re:Partially on the subject... (Score 1) 155

This is incorrect.

First, if the moon and Earth were both tidally locked, this might have some ever-so-tiny effect, but probably not enough to notice. There was a time when the fact that the Moon's center of mass is offset from its center of figure was thought to be due to being tidally locked with to the Earthâ"that has been shown not to be the case and the difference is thought to be due to volcanism and large impacts.

Note that the Earth-Moon's barycenter (center of mass) is located within the interior of the Earth, so whatever long-term, direct gravitational effect the Moon has on Earth's materials, it cannot cause those materials to move into the crust of the Earth.

The Moon orbits the Earth rather than being fully locked to it, so its differential gravitational effects on high- vs. low-mass materials would essentially average out over time (sometimes it would be pulling those high mass materials away from the center of the Earth and sometimes it would be pulling them toward the center of the Earth).

Finally, the fact that the Earth has a moon in a non-circular orbit means that it has the opposite effect from what you describe. Tides on the ocean are the most obvious effect from this non-circular orbit; the oceans are gravitationally pulled toward the moon (slightly lagging its passing). The solid earth experiences the same differential stresses due to the passing of the moon, though the strength of the solid earth greatly decreases the magnitude of its change in shape compared with the change in shape of the ocean. So, the Earth is constantly being flexed as the moon passes by (closer and then further away in its eccentric orbit of the Earth). Imagine (or do the experiment) flexing a paperclip very quickly. It heats up because of internal friction. The same is happening to the Earth. The gravitational energy expressed as tides is being dissipated as heat in the Earth's interior. This means that the Moon is (very, very, very slightly now, but a bit more so in the past) contributing to the melting of the interior of the Earth. Because massive materials (iron, etc.) will eventually sink toward the center of a fluid object, the Moon actually contributed to moving the heavier elements (iron, sulfur that binds to iron, and etc.) to the core, not to the crust as described in your post.

Comment Get your definitions straight first. (Score 1) 332

As usual, /.'s libertarians run their mouths without actually having a clue. They seek to impose their definitions of rights on others.

Instead of sitting by while they ruin another discussion, let's start with an actual, legal definition of human rights as determined by a legally-binding body instead of some knee-jerker who thinks his thoughts should extend to all humans. The Declaration of Independence actually doesn't count as a legal document (anymore), so let's dispose of that right away, even before we get to the point of dismissing the US Constitution as a whole because it only applies to one group of humans.

Let's go with the United Nations, the generally recognized body for international affairs.

Oh, Look! They went through this process already! In 1948, when the world was falling apart, they still came to an agreement on what are the basic human rights. I'm going to go with their work rather than some Randian who still thinks John Galt is a hero.

http://www.un.org/en/documents/udhr/index.shtml

The most relevant is Article 19:

Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers.

Does this give people an entitlement to a specific conduit for exercising their freedom of expression? No. But it does give people the right to communicate through any conduit they choose (as long as they don't do something that infringes on other peoples' rights to use that conduit).

Below are a few of the relevant Articles.

Article 1.

All human beings are born free and equal in dignity and rights.They are endowed with reason and conscience and should act towards one another in a spirit of brotherhood.

Article 2.

Everyone is entitled to all the rights and freedoms set forth in this Declaration, without distinction of any kind, such as race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status. Furthermore, no distinction shall be made on the basis of the political, jurisdictional or international status of the country or territory to which a person belongs, whether it be independent, trust, non-self-governing or under any other limitation of sovereignty.

Article 3.

Everyone has the right to life, liberty and security of person.
.
.
.

Article 18.

Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief, and freedom, either alone or in community with others and in public or private, to manifest his religion or belief in teaching, practice, worship and observance.

Article 19.

Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers.

Article 20.

(1) Everyone has the right to freedom of peaceful assembly and association.
(2) No one may be compelled to belong to an association.

Article 21.

(1) Everyone has the right to take part in the government of his country, directly or through freely chosen representatives.
(2) Everyone has the right of equal access to public service in his country.
(3) The will of the people shall be the basis of the authority of government; this will shall be expressed in periodic and genuine elections which shall be by universal and equal suffrage and shall be held by secret vote or by equivalent free voting procedures.

Article 22.

Everyone, as a member of society, has the right to social security and is entitled to realization, through national effort and international co-operation and in accordance with the organization and resources of each State, of the economic, social and cultural rights indispensable for his dignity and the free development of his personality.

Article 23.

(1) Everyone has the right to work, to free choice of employment, to just and favourable conditions of work and to protection against unemployment.
(2) Everyone, without any discrimination, has the right to equal pay for equal work.
(3) Everyone who works has the right to just and favourable remuneration ensuring for himself and his family an existence worthy of human dignity, and supplemented, if necessary, by other means of social protection.
(4) Everyone has the right to form and to join trade unions for the protection of his interests.

Article 26.

(1) Everyone has the right to education. Education shall be free, at least in the elementary and fundamental stages. Elementary education shall be compulsory. Technical and professional education shall be made generally available and higher education shall be equally accessible to all on the basis of merit.
(2) Education shall be directed to the full development of the human personality and to the strengthening of respect for human rights and fundamental freedoms. It shall promote understanding, tolerance and friendship among all nations, racial or religious groups, and shall further the activities of the United Nations for the maintenance of peace.
(3) Parents have a prior right to choose the kind of education that shall be given to their children.

Article 27.

(1) Everyone has the right freely to participate in the cultural life of the community, to enjoy the arts and to share in scientific advancement and its benefits.
(2) Everyone has the right to the protection of the moral and material interests resulting from any scientific, literary or artistic production of which he is the author.

Article 28.

Everyone is entitled to a social and international order in which the rights and freedoms set forth in this Declaration can be fully realized.

Article 29.

(1) Everyone has duties to the community in which alone the free and full development of his personality is possible.
(2) In the exercise of his rights and freedoms, everyone shall be subject only to such limitations as are determined by law solely for the purpose of securing due recognition and respect for the rights and freedoms of others and of meeting the just requirements of morality, public order and the general welfare in a democratic society.
(3) These rights and freedoms may in no case be exercised contrary to the purposes and principles of the United Nations.

Article 30.

Nothing in this Declaration may be interpreted as implying for any State, group or person any right to engage in any activity or to perform any act aimed at the destruction of any of the rights and freedoms set forth herein.

Comment Re:And the unions are pissed... (Score 1) 575

So, your anecdote about "teachers you know" is science? And a poll is propaganda?

I point out 1st year and 22nd year salaries.

I'm comparing the salaries between a teacher in their 22nd year with 100+ credit hours of education beyond a BS/BA and a programmer in their 5th year with 0 credit hours beyond a BS.

From your inability to distinguish between reality and your own warped biases, your inability to read, and your ad hominem attacks, it's clear you aren't actually interested in a conversation, just in attacking teachers and their supporters.

Comment Re:And the unions are pissed... (Score 3, Interesting) 575

Let's do that, then!

Teachers work about 200 days per year.

Teachers work about 11.5 hours/day (http://www.scholastic.com/primarysources/pdfs/Gates2012_full_noapp.pdf)

200 days * 11.5 hours/day = 2300 hours per year.
A typical job with a 40-hour/week nets 2088 hours/year.

So, already your myth is busted, but let's continue.

The pay schedule for teachers in my area ranges from:
$30,943 for a BA first year teacher
to
$60250 for a BA+100 and 22 years experience.
(or MA+60; A JD from George Mason requires a BA+89 hours)

$30,943/2300 = $13.45 per hour.
$60250/2300 = $25.56 per hour.
These include benefits, and is before taxes, so the take-home is significantly less than this.

So, let's talk about equal pay for equal work.

In my area, A Senior Software Engineer with a BS+5 can expect to make between $65k and $131k/year.
65,000/2088 = $31.13/hour
131,000/2088= $62.74/hour

And this software engineer isn't at a gaming company with 80-hour work weeks, this is a 9-5+occasional hours job.

Comment Re:And the unions are pissed... (Score 4, Informative) 575

And I think you have a skewed perception of a real teacher's work day and a skewed perception of actual pay rates.

11.5 hours/day is the norm.
(http://www.scholastic.com/primarysources/pdfs/Gates2012_full_noapp.pdf)

The school year for students is 180 days. Teachers must be there a week early and leave a week later. They also have work days throughout the year that the students are not there for. This gives about 200 days per year of work.
200 days * 11.5 hours/day = 2300 hours per year.
The 40-hour work week gives 2088 hours per year.

The pay schedule for teachers in my area ranges from $30,943 for a BA, first year to $60250 for a BA+100 (or MA+60; A JD from George Mason requires a BA+89 hours) and 22 years experience.

$30,943/2300 = $13.45 per hour.
$60250/2300 = $25.56 per hour.
These include benefits, so the take-home is significantly less than this.

Comment Re:16 Megapixles (Score 3, Interesting) 66

First, the submitter got the value wrong. The Large Monolithic Imager (LMI) has 36 MPixels (technically, it has 6144x6160 = 37,847,040 pixels), not 16 MPixels.

http://www.lowell.edu/dct_instruments.php

Second, being a scientific instrument, it has a rather lot of requirements that your Nikon doesn't; the number of pixels is only one of several parameters engineers trade against each other when building a camera for scientific use.

Comment Re:What percentage of cancers leverage that? (Score 2) 94

You can usually get past a paywall by going to your local public or university library and accessing the article there. Tedious, I know.
Conclusions from the article:

Here we have identified a selective cap-dependent translation initiation mechanism that operates independently of eIF4E and that targets mRNAs for protein synthesis during hypoxia. The results suggest that the HIF-2αâ"RBM4â"eIF4E2 complex is extensively involved in coordinating the translation response to low oxygen availability and is therefore essential in cellular oxygen homeostasis. This complex probably recruits functional homologues of the canonical eIF4E-dependent pathway, as well as distinct components, to initiate hypoxic protein synthesis. This process is regulated by the oxygen-sensing machinery first identified as the main regulator of the transcriptional response to hypoxia13, 14, 15, 16. A human population that recently migrated to the Tibetan highlands contains a point mutation in the gene encoding HIF-2α (EPAS1), further emphasizing the evolutionary role of HIF-2α in the adaptation to high altitude and low oxygen tension27. The target mRNAs code for proteins such as EGFR, PDGFRA and IGF1R that are implicated in the adaptive response to hypoxia as well as a wide variety of biological processes including development and cancer. The role of these receptor tyrosine kinases in human malignancy is particularly well documented and they are at the centre of targeted therapy11, 28. EGFR is often overproduced by tumours that harbour a wild-type EGFR gene, suggesting that cancer cells hijack the eIF4E2 pathway for their proliferative advantage29, 30. The results shown here provide the foundation for further investigation of the adaptive properties of the basic protein synthesis machinery in response to environmental conditions.

Comment Magma ocean != 100% melt (Score 2) 48

A magma ocean is not a 100% liquid rock layer beneath the surface.

The observations made by this team are consistent with a 50 km-thick layer about 50 km below the surface (that is, within the mantle) with >=20 volume% melt fraction. This work is based on how Io affects Jupiter's magnetic field.

Other research teams have demonstrated, since the 1990s that Io should have a mantle with a >= 20 volume% melt fraction at some depth in the mantle--it was never clear where this magma ocean was located. This work is based on observations of the surface eruptions and models for how quickly silicate lavas cool.

The fact that these agree is significant.

A substantial portion of Io at 100 volume% melt would actually not work because pure liquid does not dissipate enough of the energy from the tidal forces to maintain 100 volume% melt. That is there's a feedback loop between Io's interior and the tidal flexing:

* Too much liquid in the interior and the energy dissipation will decrease significantly, allowing the liquid to cool enough to solidify significantly.
* Too little liquid and the interior would quickly dissipate enough tidal energy (in the form of friction) to significantly melt the interior.

So, Io's orbital resonances keep a small part of its mantle molten at between 20 volume% and 50-70 volume.

That there's now a depth associated with this magma ocean is actually quite significant. We can start better understanding the role volatiles play in Io's volcanism now that we know where the molten rock is coming from.

Comment Re:Okay, hold on a minute. (Score 2, Interesting) 184

Venus is basically the same size as the Earth.
Earth's mean radius is 6,371 km. Venus' mean radius is 6052 km.
The masses are also similar, as are their compositions.

A more likely control on whether plate tectonics may be initiated is the existence of liquid water at the surface and within the lithosphere of the planet in question. Water greatly reduces the yield strength of plates (by as much as 62% when going from low to moderate temperatures compared with a drop of only 39% for dry olivine). So, while plate tectonics seems to be necessary for life, water (necessary for life) may be necessary for plate tectonics. Venus is just at the range from the Sun where it could have lost all of its water too quickly for plate tectonics to initiate (especially if it lost the water long before the planet was mostly still molten).

Comment So? (Score 5, Insightful) 463

So, someone represented a company that has different ideas than you do...and that's a problem because?
Do /.ers really believe that their employer is their sole identity defining characteristic?
Are all of you who work for asshole-bosses also assholes?
It sure seems that that's what you're all saying when you go on these witch-hunts.

Comment Re:'habitable zone' .. (Score 1) 97

I'm not sure what you mean when you talk about 10% of a planetary surface and AUs.

Earth's surface area is 5.1x10^8 km^2. 10% of that is, obviously, 5.1x10^7 km^2. The land area of the US is about 9.8x10^6 km^2, so we're talking about 5-times the land area of the US. None of this has anything to do with distance from the star, just to do with the radius of the planet.

But, as you say, the point of 10% isn't that it's a special number; it's a starting point. Notice that this definition explicitly excludes any gaseous planets from the get-go. That's not necessarily fair, of course, but we've got to start somewhere, and rocky planets are a LOT simpler to understand w.r.t. possibilities of life.

Earth's average albedo isn't really all that controversial or problematic. For example, we can say that the poles probably had such and such an albedo at such and such a time (based on climate models based on core samples), the clouds are difficult for a specific times (decades or so), but again the climate will dictate some average cloud cover that is relatively accurate over long periods over the entire Earth.

Going into more detail would require an actual climate model (such as the Hadley model), which doesn't make much sense for extrasolar planets since we know next to nothing about atmospheres (especially their composition) on most extrasolar planets. Of course, we can speculate and use places like Titan, Mars, Venus, Earth, and Triton as jumping-off points for planets that are certain distances from their parent star.

Milankovitch cycles are certainly included in long-term habitability or continuous habitability zone research, but we're really limited by not knowing anything about the obliquity/precession cycles of extra-solar planets, which are quite dependent on specific circumstances of those planets.

The T-tauri phase of the pre-main sequence stars would strip almost any magnetic field-protected atmosphere from most planets, so we're fairly confident that any planets found orbiting such stars are uninhabitable. In fact, there are a lot of stars that can be ruled out (of having any sort of habitable zone) just by looking at them.

Habitability zones are for "well-behaved" stars with well-behaved planets. Some researchers are looking at double or triple star systems, so we'll have a better understanding of the possibility of life in such systems as time goes on.

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