In my class which inherited TreeViewItem  I used a field to store the parent TreeView object  TreeView _parentTreeView   Since TreeView will definitely have a reference to the TreeViewItem while the TreeViewItem holds a reference to the parent. Will this prevent both TreeView and TreeViewItem from being garbage collected?
I'm trying to run down a memory leak in a windows forms application.  I'm looking now at a form which contains several embedded forms.  What worries me is that the child forms, in their constructor, take a reference to the parent form, and keep it in a private member field.  So it seems to me that come garbage-collection time:  Parent has a reference to the child form, via the controls collection (child form is embedded there).  Child form is not GC'd.  Child form has a reference to the parent form, via the private member field.  Parent form is not GC'd.   Is this an accurate understanding of how the garbage collector will evaluate the situation?  Any way to 'prove' it for testing purposes?
Chat messages should use consistent icon in iOS app It'd be nice if the chat notifications in the feed used the default Stack Exchange icon like the ones in the inbox do*:     Since items in the feed are grouped so that multiple items from the same site , the site icon helps delimit grouped items a bit less subtlely than the grey divider lines, and chat replies' lack of one causes them to sort of blend in to the previous group.  *Ideally it'd use the icon of the site the room was associated with, but I don't think that information is readily available Does this recording sound like the pulses emitted by bats? Out of curiosity, I recorded sounds in an area with lots of bats, hoping to be able to &quot;hear&quot; the bats communicating by lowering the ultrasound to a level down to the frequency which can be heard by a human. After a bit of post-processing, I actually hear interesting sounds, but I'm not sure about the origin. It seems that the frequency of the pulses is too low compared to bats. . Are those actual sounds emitted by bats? If not, what other animal could be the source of those sounds? About the audio The sound was recorded at 10 p.m. at  near a river, with more of a dozen bats flying in this zone. There is a bridge nearby, and the sides of the river are flat concrete, which means that there are a lot of opportunity for sound reflection (although high frequency sounds don't reflect well). Zoom H5 with the default XY directional microphone was used. The bitrate was set to 24-bit. Unfortunately, I used the sampling frequency of 48 kHz instead of the maximum 96 kHz. The following transformations were made to the original audio:  The pitch was shifted by -12 semi-tones, which means that the 20 kHz sound becomes 10 kHz, and 15 kHz becomes 7.5 kHz.   All sounds below 6 kHz were removed.  The sound was amplified.  Severe noise reduction was applied to eliminate everything but the actual sounds emitted by the bats.   The empty parts of the audio were removed.  The sound was amplified once again.   Frequency The frequency analysis of the transformed audio a peak around 9 kHz (18 kHz in the original audio), slowly fading to suddenly drop at 16 kHz (32 kHz in the original audio).   contains many sources with different indications about the frequency range of the sounds emitted by bats, only a few referencing the frequencies low enough to be heard by a human:  Frequency Produced 10kHz-120kHz Ramsey, Gabriel, McGuirk, Phillips, Watenpaugh. Holt Physical Science. New York: Holt, Rinehart and Winston Publishers, 1986.  while most agreeing on the fact that bats use frequencies higher than 20 kHz.  Most bats use frequencies in the range 20-80 kHz, only a few bats use frequencies less than 20 kHz. Long, M.R. &amp; Savage, J.G. Mammal Evolution. New York: Harper, 1976: 108.  The observed range of 18..32 kHz seems too low compared to the sources, but I have an impression that the frequencies vary a lot between different species of bats. Pattern When viewing the audio track (see below), each cry consists of several pulses in two to three sub-groups which are in turn in two groups. Each peak is a bit less than 1 ms. The second group occurs from 40 to 200 ms. after the end of the first one. Each sub-group is separated by 5 to 10 ms. The frequency of every pulse doesn't vary, except the very first pulse. The first cry starts by a more quiet pulse at 6 kHz (12 kHz in the original audio). The second and third cries don't follow this pattern.  indicates that there are three categories of sounds emitted by the bats:  Short clicks,  Frequency-swept pulses,  Constant frequency pulses.   It looks like it's still the third category which we are observing here, and the overall pattern looks similar to the one described for the bats. The gap between the left and the right track is mostly irrelevant: at higher frequencies, microphones become more and more directional, and the sound is reflected less, which leads to such difference.     Note: this question was considered to be on-topic at Biology.SE on . Why is compactness in logic called compactness? In logic, a semantics is said to be compact iff if every finite subset of a set of sentences has a model, then so to does the entire set.   Most logic texts either don't explain the terminology, or allude to the topological property of compactness. I see an analogy as, given a topological space X and a subset of it S, S is compact iff for every open cover of S, there is a finite subcover of S. But, it doesn't seem strong enough to justify the terminology.   Is there more to the choice of the terminology in logic than this analogy? Possible Duplicate:          If I am using the word model in the context of financial models and the UK, then which of these words should I use? Also, are there any key difference in the meanings of the two? how to plot two graphs in a single sheet? I am new to Latex. Cann some one tell me how can I plot two graphs in a single page and How can resize the legend. I have attached the picture how the legend looks. I need it out from the plot and how can i have gridded lines in the plot. Please help me. My code is as follows: \documentclass[12pt, a4paper]{report} \usepackage{filecontents,pgfplots}  \begin{filecontents}{mydata.dat} m0_FEED, AT 773.15K, AT 823.15K, AT 873.15K, AT 923.15K, AT 973.15K 0.005, 1.30E+04, 12959.71536,12959.71536,12959.71536,12959.71536 0.007, 1.81E+04, 18145.78478,18145.78478,18145.78478,18145.784 0.009, 2.33E+04, 23333.9541,23333.9541,23333.9541,23333.9541 0.011, 2.85E+04, 28524.71381,28524.71381,28524.71381,28524.71381 0.013, 3.37E+04, 33718.48576,33718.48576,33718.48576,33718.48576 0.015, 3.89E+04, 38915.61947,38915.61947,38915.61947,38915.61947 0.017, 4.41E+04, 44116.39602,44116.39603,44116.39603,44116.39603 0.019, 4.93E+04, 49321.02848,49321.02848,49321.02878,49321.02849 0.021, 5.45E+04, 54529.67237,54529.67238,54529.67238,54529.67238 \end{filecontents}  \begin{document}   \pgfplotstableread[col sep=comma]{mydata.dat}{\mydata} \begin{tikzpicture}[scale=1.8] \begin{axis}[minor tick num=1, xlabel=Degrees, ylabel = temperature] \addplot [black,very thick] table [x={m0_FEED}, y={AT 773.15K}] {\mydata}; \addplot [red,very thick] table [x={m0_FEED}, y={AT 823.15K}] {\mydata}; \addplot [blue,very thick] table [x={m0_FEED}, y={AT 873.15K}] {\mydata}; \addplot [green,very thick] table [x={m0_FEED}, y={AT 923.15K}] {\mydata}; \addplot [dashed,yellow,very thick] table [x={m0_FEED}, y={AT 973.15K}] {\mydata}; \legend{AT773.15K, AT823.15K, AT873.15K, AT923.15K, AT973.15K} \end{axis} \end{tikzpicture}  \begin{filecontents}{mydatax.dat} m0_FEED AT 773.15K  AT 823.15K  AT 873.15K  AT 923.15K  AT 973.15K 0.005   4.06E+03    4601.511738 5147.966831 5703.120845 6267.035737 0.007   5.69E+03    6439.241858 7204.278989 7981.494608 8625.923 0.009   7.31E+03    8274.205759 9257.824928 10257.10215 11272.14896 0.011   8.92E+03    10105.75535 11307.95656 12529.29539 13769.90815 0.013   1.05E+04    11933.33165 13354.1149  14797.51533 16263.69405 0.015   1.21E+04    13756.46929 15395.83457 17061.29661 18753.04129 0.017   1.37E+04    15574.79159 17432.7389  19320.26254 21237.57317 0.019   1.53E+04    17388.009   19464.53834 21574.12348 23717.00014 0.021   1.69E+04    19195.90581 21491.01717 23822.664   26191.10653 \end{filecontents}  \pgfplotstableread{mydatax.dat}{\mydatax} \begin{tikzpicture}[scale=2] \begin{axis}[minor tick num=1, xlabel=Degrees, ylabel = temperature] \addplot [black,very thick] table [x={m0_FEED}, y={AT 773.15K}] {\mydatax}; \addplot [red,very thick] table [x={m0_FEED}, y={AT 823.15K}] {\mydatax}; \addplot [blue,very thick] table [x={m0_FEED}, y={AT 873.15K}] {\mydatax}; \addplot [green,very thick] table [x={m0_FEED}, y={AT 923.15K}] {\mydatax}; \addplot [dashed,yellow,very thick] table [x={m0_FEED}, y={AT 973.15K}] {\mydatax}; \legend{AT773.15K, AT823.15K, AT873.15K, AT923.15K, AT973.15K} \end{axis} \end{tikzpicture}   \end{document} Create an object with dynamic property names How to reconcile the cashless human/Federation society with human traders and merchants Distance between footnote and the line above it In WPF, what are the differences between the x:Name and Name attributes? Is transferring to another university an option for an unhappy PhD student? One of my Fellows asked me whether total induction is applicable to real numbers, too ( or at least all real numbers ≥ 0) . We only used that for natural numbers so far.  Of course you have to change some things in the inductive step, when you want to use it on real numbers.  I guess that using induction on real numbers isn't really possible, since $[r,r+\epsilon]$ with $\epsilon > 0$, $r \in \mathbb R$ is never empty.  Can you either give a good reason, why it isn't possible or provide an example where it is used? Can I get a rebate after using my HSA? Acquiring drive names (as opposed to drive letters) in Java On my Windows machine, my main hard drive has the letter C: and the name "Local disk".   To list the drive letters in Java on Windows, the File object has the static listRoots() method. But I can't find a way to acquire the drive names (as opposed to the drive letters) on Windows.  Has anyone tried this before? ,  and 1 still show the old bar. 1 See What white point temperature should I set my LCD monitor to? I've got the Xrite Eye One Display 2, and tried the advanced calibration today for the first time.  It asked what white point I wanted, and had a default of 6500K.  I didn't realize that was up for discussion!  I would have assumed the daylight temperature, around 5500K, would be desired.  What temperature do I want my whites to be? Why can't white just be white?! My document should be letterpaper and my attachments should be a4paper. I had high hopes for the \newgeometry command from the geometry package, but the documentation says      \newgeometry is almost similar to   \geometry except that \newgeometry   disables all the options specified in   the preamble and skips the   papersize-related options: landscape,   portrait and paper size options (such   as papersize, paper=a4paper and so   forth).   Any help is appreciated! Voting to Close after Accidentally Voting to Leave Open When reviewing on SO, I accidentally pushed the "Leave Open" button on a post that clearly should've been closed. I pushed the back button and saw that in the review panel my vote to keep open had been locked and it said:     PhpMyCoder voted to leave open 1 minute ago   So I clicked on the question heading to go to its page and I clicked the close link on the question page and voted to close for the relevant reason. However, when I returned to the review page (and did a hard refresh) it still said:     PhpMyCoder voted to leave open 2 minutes ago   Is it possible to vote to leave open and vote to close at the same time? I assume not. In which case, I'd say this is a bug because it should've updated to say:     OtherUser and PhpMyCoder voted to close 2 minutes ago I am looking for a way to output all page IDs from the following menu:   &lt;?php wp_list_pages('depth=1&amp;exclude='3,5,11')); ?&gt;   Only top level pages needed, therefore the 'depth=1'.  Any help appreciated. Detect whether Excel workbook is already open Points of a Measure Zero Sets Covered by Intervals Infinitely Many Times Given a measure zero set $E$, by definition we have forall $\varepsilon &gt; 0$, a covering of $E$ by intervals whose lengths sum to $&lt; \varepsilon$.  I want to prove that we can cover $E$ in intervals such that the sum of the lengths the intervals is $&lt; 1$ and each point in $E$ is contained in infinitely many of the intervals.  Do you know how to prove this? Thank you