Homework Help

I was wondering if anyone knows how to solve/approach this problem. A group of people from my class have been working on it and we all come to different conclusions. Thanks in advance for your responses. An E. coli F- strain has the following genotype: S-U-R-I-E-C-. Three different Hfr strains, all carrying S+U+R+I+E+ and C+ markers and all having lambda phages integrated at the same specific site in their chromosomes are mated with the F strain in separate matings. The interrupted-mating results are given below. The numbers indicate time (in minutes) when different donor markers appeared in F- cells after conjugation began. Assume that the E. coli map con…

Hi, So basically there are 3 parts to this one question: 1a) Suppose an attacker tries to find out your password with an on-line attack by repeatedly trying to log onto your account with guessed passwords. Further suppose that the system logon is set up in such a way that no more than consecutive unsuccessful logon can be attempted within a period of 10 minutes (before the account would be temporarily disabled and the system administrator notified). Hence, an attacker can try at most 2 password guessing logon attempts every 10 minutes. Suppose your password consists of 6 (case sensitive) alphanumeric characters randomly chosen. How long it would take, on the…

Hey everyone- This is basically just a curiosity question. We ran a column and an SDS page for protein separation. We separated Ferratin, BSA, and Cyt C (they eluted in that order). Here is a pic of my annotated SDS page: (the last 4 wells on the right are unknowns, so that is why they are out of order) Also, the scale is arbitrary, 0=start, 100=finish Does anyone know what the wells marked (21) could be? They appear to be 180ish kDa according to the ladder. However, ferratin subunits are 20kda, BSA is 66kda, and cyt c is 12kda. Any ideas? They appeared to have eluted at the same time as BSA. Thanks!

OK guys, so I'm doing some work on a movie and please bare in mind it's fictional (hey,it's the movies!). But I need a character to smoke an oxygen cigarette(please don't ask why). Now, I'm talking about one of those metallic contraptions, I'm talking about something that actually looks like a real cigarette and unless you pulled it apart and examined it's "anatomy" you wouldn't know the difference. So I've come up with this idea that the cigarette is comprised of briquetted sodium chlorate and the cigarette paper is lined with thermal insulation. Would this theoretically work? If not, why? And do you have any suggestions on how to devise an oxygen cigarette that might no…

Could someone help me , how to simplify this expression not c xor (not b or c) Please help me

hello, im paul j. im studying cellular and molecular physiology (graduate degree). i chose my thesis about the anticancer effect of micromeria barbata. the study havent been done here in my area and theres a a local species of the same family called micromeria libanotica. im starting to pannic because i need references in order to finish my bibliography. i cant get access to recent articles related to my topic. all i ask if someone could just send me some articles. it will be the biggest help i could ever ask for and i cant be more thankful for any kind of assistance.

i'm trying to work my way through this problem but i dont understand it. HCN is a weak acid and bromine is a good leaving group. so what i have here is a sn1 reaction. right? or is it an e1? the HCN is too weak to substitute the bromine so the bromine has to dissassociate in the first step before the CN- can attack. but what do i do then?

Chem: can someone tell what the structure is? I see from IR spectrum that I have OH, C-H sp2, C-H sp3, C=C aromatic, C-O groups. I see that I have 91, 134, and 149 fragments. I know that 91 is benzene-ch2+ fragment. I don't know what the 134 or 149 fragments are. I know that 149 is actually the whole structure. Looking at proton and C13 NMR i see that i have OH, benzene, CH3, CH2, CH groups, not sure if i got all of those groups right. I can't seem to get what the structure is. Here is spectra: http://i39.tinypic.com/zmjypd.png http://i44.tinypic.com/wkst91.jpg

.....CH3..............................................CH3 .....|....................................................| ..I-C-H................+ NaCN...->............CN-C-H.............+.......I- .....|....................................................| HO-C-H..........................................OH-C-H ......|...................................................| ....CH3................................................CH3 i have sneaky suspicion that after the CN takes the place of I it switches around to the back of the carbon chain, opposite the side of the OH, but thats as far as i can get.

i understand the halogen is substituted by the nucleophile (CH3O-) in most cases but how do i tell which is the exception? problem: R-X + CH3O- CH3OR + X- which haloalkane would not undergo the reaction above? CH2=CH-CH2-Br CH3Cl CH2=CH-I CH3CH2Br CH3CH2CH2Cl

Ok guys in my school we are on thesystem of IB curriculum, and over here we need to write this one 4000 wordessay on a particular area of knowledge (Mathematics in my case), its known asthe Extended Essay. Now i have a topic, i just dont know if its good enough,because no one in our school is that mathematically capable of overlooking atmy topic including the teachers, so i was thinking some more experienced peopleover here could help out. So here is my researchquestion: "Do all polygons with n number of sides associate with Φ ?, ifso, aspect the 3 dimensional polyhedron "dodecahedron" and"Hexahedron" in relation with the Golden ratio." How viable would this be to…

Well, I'm using catechin for my polyphenol oxidase assay to determine the substrate specificity. But the problem is when I try to use 50mM above, the concentration seems to be very high which the spectrophotometer shows more than 4.500. What should I do?? I couldn find any info from the website or journals. Should I dilute it? And I should dilute the substrate only or together with the enzyme? The total volume is 2.9ml, so if i dilute it using 1:2 ratio, means 2ml of buffer and 1ml of substrate? The total volume of blank is 3.0ml of buffer + substrate. Please help me ! Thanks a lot !!

Hello everybody: Please, I need help interpreting what is being represented in an osmotic fragility curve of erythrocytes. I attached the pdf with the article. My questions are regarding the curve represented in Figure 1. I do not know what (C1-10, C1-50 ,C1-100 and C2-10, C2-50 and C2-100 represent). Also I don´t understand why (curcumin membrane-stabilized erythrocytes) need to be used as positive control. I would really appreciate your help. Looking forward to hear from you. 2886-22206-3-PB.pdf

Hi there, I am currently doing an assignment for my undergrad degree and I am really struggling to figure out what the control conditions are in the following two studies: 1) http://www.hfac.gmu.edu/people/mpeters2/Courses/Psy768-s10/Readings/Blotvinick1999.pdf 2) http://scan.oxfordjournals.org/content/early/2012/01/20/scan.nss010.abstract I know it's a big ask, but if anybody is good at interpreting fMRI, then your help would be massively appreciated. Many thanks, John Just to clarify, I understand the methodology used and what they did. I'm just struggling to figure out if it is one of the conditions (i.e. compatible trial in the Botvinick pa…

I'm sorry for this noob topic but I really need help. I'm not asking anyone to do the program for me but I need some guidance and my professor did not help me at all when I went to visit him. Assignment: This assignment is designed to help you get more familiar with basic assembly language instructions, the IO macros, and the bsvc system. For this assignment, you will write a program in Motorola M68000 assembler that takes as input a four digit year, and prints the day of the week for Christmas of that year. Here is the formula to solve the problem: Input: Month Hardcoded, month = 12 Day Hardcoded, day = 25 …

Hi I was wondering if someone could provide a link or post/attach the full reaction mechanism (including all steps) of the dehydration of a secondary alcohol, say 2-butanol including all the end products (is there a hydrogen ion left at the end?) My instructior showed the reaction with H2PO as the catalyst but I think I copied it wrong and I haven't been able to find it online. Thanks.

In the following problems, Θ = 20 + units digit of your day of birth. For example, if you were born on April 1st, then Θ = 20 + 1 = 21. If you were born on March 30th, then Θ = 20 + 0 = 20. 1. Alok and Bhanu play the following game on arithmetic expressions. Given the expression N = (Θ + A)/B + (Θ + C + D)/E where A, B, C, D and E are variables representing digits (0 to 9), Alok would like to maximize N while Bhanu would like to minimize it. Towards this end, they take turns in instantiating the variables. Alok starts and, at each move, proposes a value (digit 0-9) and Bhanu substitutes the value for a variable of her choice. Assuming both play to their opti…

We did an experiment to find out how much sulphate was in a sample of homemade fertiliser. This is the method: Å Finely grind a small quantity of fertiliser using a mortar and pestle. Weigh out accurately about 1.0 g of fertiliser into a 100 mL beaker. Record the mass of fertiliser to three decimal places. Ç Add about 50 mL of deionised water and stir to dissolve as much of the fertiliser as possible. Filter the mixture into an approx. 500 mL beaker, washing the residue (the solid trapped in the filter paper) several times with a small amount of deionised water. É Add about 3 mL of 2 M hydrochloric acid to the filtrate (the solution passes throug…

hello i am making a research and i need you to take this survey plz 2012 Survey i need it so much thank u any way

Hi, I'm having some problems with home work and i stuck. 1. How you would prepare 5 mL of a 75 ppm Cu solution from a 0.015 mol/L solution of copper (II) nitrate. Show full details of your working I know that 75 ppm Cu is equal to 75 mg of CU per litre of solution, so in 5ml we have: 0.075 g L(-1) x 5 x 10(-3) = 0.375 x 10(-3)g mollar mass of Cu(NO3)2 = 187,55 g/mol, it's really confused me the information of 0.015 mol/L solution. 2. A 400 µL sample of a water sample from a polluted river was added to a 25 mL volumetric flask and tested for phosphate using a colourimetric method by adding the required reagents and making to the mark with …

Given the network address as : 193.12.111.0 and subnet mask as: 255.255.255.224 . <br style="font-family: verdana, geneva, lucida, 'lucida grande', arial, helvetica, sans-serif; font-size: 14px; "><br style="font-family: verdana, geneva, lucida, 'lucida grande', arial, helvetica, sans-serif; font-size: 14px; "># how to calculate the Total Subnet ?<br style="font-family: verdana, geneva, lucida, 'lucida grande', arial, helvetica, sans-serif; font-size: 14px; ">#How many unusable host/Subnet?<br style="font-family: verdana, geneva, lucida, 'lucida grande', arial, helvetica, sans-serif; font-size: 14px; ">#What is the IP address of : 193.12.111.109 -u…

I have to write the background/introduction (part of my report) on this: How does salt effect the boiling point of water? Basically, my teacher only wants me to do the physics side of this experiment, not the chemical side. She also wants the background to be about 1+ page/s (purely on the background). Could anyone just give me some pointers on what to write in the paragraphs and what issues/topics I should address within the background...(also because if you wrote it for me it would be breaking the rules, and also copyright) Thanks in advance oh, and by the way, I'm new to SFN (as in today new) so please don't be hard on me and it's grade 11 work, but it…

Can anyone help me by a generalized equation for the time period of all types of pendulums?

could anyone tell me functions and mechanisms of P2Yreceptors in detail?

I have a small case study, nothing special but it kinda got me a bit. The main topic is pretty much on the Central Nervous System, Action Potentials, and so on. It asks what would happen if the extracellular potassium is ten times higher than normal in the brain tissue. I know it would cause some sort of seizure, the extra potassium would make it depolarize to make an action potential. But I don't know how it would cause a seizure effect. Would that skip the refractory period forcing it to depolarize at a faster rate giving you seizures?