# Welcome HOW360°, Questions & Answer

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## What are some readily available, easy to test, bacteria?

I want to do a science fair experiment about how bacteria interact with 5-carbon vs. 6-carbon sugars, and I want a bacteria that is easy to test and is readily available. Any ideas?

biology

## Detecting coplanarity by given erroneous pairwise distances

This is the question I asked four months ago and took very satisfactory answers. However, I tackle a new problem now. Here, I summarize the original problem: We have points in 3D space. We do not

computer-science

## Using a step-counting function in a Turing Machine construction

I have an question relating to the elementary foundations of Turing Machine theory. I would like to have a clarification of the status of a function $\phi$ (a mapping between TM indexes) I shall

computer-science

## How to show that a "reversed" regular language is regular

I'm stuck on the following question: "Regular languages are precisely those accepted by finite automata. Given this fact, show that if the language $L$ is accepted by some finite automaton,

computer-science

## Is Karp Reduction identical to Levin Reduction

Definition: Karp Reduction A language $A$ is Karp reducible to a language $B$ if there is a polynomial-time computable function $f:\{0,1\}^*\rightarrow\{0,1\}^*$ such that for every $x$, $x\in A$ ...

computer-science

## Pdf for distance between two uniform random points in a circle

This is my first post in the group and I would be very thankful for any help. I am trying to develop a probability distribution for a performance analysis in my thesis. I am trying to look in to

mathematics

## Is this sentence of "mixed construction"?

In English class, we've discussed the following sentence and considered if it is of mixed construction: The increase in the number of times his name appeared on such lists after the poem was

english-language

## Is episome a plasmid or a virus?

A plasmid is a small DNA molecule that is physically separate from, and can replicate independently of, chromosomal DNA within a cell. In general, in eukaryotes, episomes are closed circular DNA

biology

## Why do cucurbits produce so much fluid when their stems are cut?

When carrying out some germination tests on species in the Cucurbitaceae, I notice that young plants of this family produce a lot of clear fluid when they are dissected. Most plants I dissect do not

biology

## What kind of arthropod/animal is this?

Can anyone identify this strange creature? I live in a very urban part of Montreal, Canada. It wasn't moving (seemed dead) and although the image is huge, it wasn't as big as it seems (a cou

biology

## Essential amino acid codons

Essential amino acids also have codons.Still they are needed by humans through diet?Will those codons do synthesize amino acids for some other purposes in humans or not?If so, what is the purpose?e...

biology

## How are bracket ellipsis [...] used in quotations?

I see this type of syntax often, but I do not know how, when or where they should be used. "It is the case that [...] the inconvenience is altogether imaginary." Is it okay to use if I

english-language

## A word which means the opposite of "something that works in parallel"

If I want to describe two things happening at the same time, I can use the words parallel or concurrently. In some cases, simultaneously would also work. More suggestions are available in the oppos...

english-language

## Fisher's Geometric Model for Dummies

Fisher's geometric model is still today one of the most important and fundamental model in evolutionary biology but it seems to me that most student in evolutionary biology don't really unders

biology

## How do I prove the arithmetic-geometric mean inequality?

I am following along with this bare-bones proof of the arithmetic-geometric mean inequality with two real numbers. I'm having difficulty understanding the logic behind this step: 

mathematics

## Solving a PDE wave equation with initial conditions and boundaries (from Strauss's PDE, exercise 3.2.6)

The problem is: Solve $u_{tt}=c^2u_{xx}$ in $0&lt;x&lt;\infty, 0\leq t&lt;\infty,u(x,0)=0,u_t(x,0)=V$, $u_t(0,t)+au_x(0,t)=0$. So I get how $u(x,t)=tV$ for $0&lt;ct&lt;x$. Howev

mathematics

## Reference request: the pronunciation of Law French?

Would anyone happen to know of a systematic account of the English pronunciation of legal and parliamentary terms and phrases of Anglo-Norman French origin, or more generally, of Law French? When it

english-language

## Natural examples of deformation retracts that are not strong deformation retracts

The question here asks for examples of deformation retracts which are not strong deformation retracts. A comment is given refering the asker to Exercise 0.6 in Hatcher. (The description of this space

mathematics

## Is climate chaotic?

The atmosphere is a highly dynamical system, and exhibits many chaotical features. An operational weather forecasting model tries to model an initial value problem, in fact one of the most famous

earth-science

## How Many Diphthongs Are There In English?

I was talking to a person who said that there were only two. I think she said that the "ou" in house is one of the two. I told her that the way the letter "i" is pronounced is a d

english-language

Often for the DNA glycosylase enzyme assay we can see that the DNA glycosylase is incubated with oligonucleotide in 37C and then reaction is stopped by addition of formamide gel loading buffer (80%

biology

## Should the abbreviated forms of Latin terms be placed in italics?

When writing English, one often uses Latin terms, such as exemplī grātiā, opere citātō, and id est, but in abbreviated forms, "e.g.", "op. cit.", and "i.e.". When wr

english-language

## Why does "ow" have two different sounds

Why is it that the "ow" in now makes the aʊ sound while "ow" in snow makes the oʊ sound? Has this always been, was it spelled differently and then changed, or was it spelled this

english-language

## Do Americans pronounce "Ellen" and "Alan" in the same way?

Do Americans pronounce "Ellen" and "Alan" in the same way? I am especially concerned with the first vowel. EDIT: Here is a quote that may be a case in point: Being a Brit als

english-language

## Is the pronunciation of the letters "Y" and "I" supposed to be identical?

My son and I were reciting the Spanish alphabet recently. "Y" is i griega, which means "Greek i." This got me thinking about the English letter Y and its function in our alphabet.

english-language