Questions
Antibiotics are used to treat a wide variety of bacterial infections and have saved millions of...

Antibiotics are used to treat a wide variety of bacterial infections and have saved millions of lives since they were first introduced in the 1940s and 1950s. However, due to both overuse and misuse, many are no longer effective and The World Health Organisation (WHO) considers the emergence of new antibiotic-resistant bacteria to be a serious threat to global public health.

According to their mechanism of action, antibiotics can be divided into three main groups, those inhibiting cell wall synthesis, those inhibiting protein synthesis and those that inhibit nucleic acid synthesis. For example, penicillin and its related compounds prevent susceptible bacteria from creating a cell wall. They do this by binding to and inactivating an enzyme (transpeptidase) necessary for the cross-linking of peptidoglycan in the wall, thus stopping its formation. Resistance to this antibiotic is due to the bacteria producing its own enzyme called beta-lactamase which breaks the ring structure of the penicillin and prevents its ability to bind to the bacterial transpeptidase.

As with all proteins, beta-lactamase is encoded by a section of DNA – but how does that DNA and the ability to produce a new protein transfer from one population of bacteria that have resistance to another population that don’t?

Other than direct transfer from parent to daughter cell, horizontal transmission of DNA between different genomes also occurs. Horizontal gene transfer is made possible by the existence of mobile genetic elements, such as plasmids (extrachromosomal genetic material), transposons (“jumping genes”) and bacteria-infecting viruses (bacteriophages). These elements are transferred between organisms through different mechanisms, which in prokaryotes include transformation, conjugation, and transduction.

  • Write a sentence for each of these mechanisms describing the manner in which the DNA can be transferred from one cell to another.
  • Choose a disease or an organism that has a well-documented mechanism of resistance (such as methicillin resistant Staphylococcus aureus - MRSA or tuberculosis) and see if you can identify the gene or genes that confer resistance and the method of DNA transfer thought to contribute to its spread. This may be from one organism to another or may simply be passed down from mother to daughter cell due to environmental pressure.
  • Finally, discuss the danger that antibiotic resistance poses in today’s society, consider how man has contributed to this and suggest any strategies that you think may be able to halt it or prevent its expansion

In: Biology

A proton is located at the origin, and a second proton is located on the x-axis...

A proton is located at the origin, and a second proton is located on the x-axis at x1 = 5.36 fm (1 fm = 10−15 m).

(a) Calculate the electric potential energy associated with this configuration. J
(b) An alpha particle (charge = 2e, mass = 6.64 ✕ 1027 kg) is now placed at (x2, y2) = (2.68, 2.68) fm. Calculate the electric potential energy associated with this configuration.  J
(c) Starting with the three particle system, find the change in electric potential energy if the alpha particle is allowed to escape to infinity while the two protons remain fixed in place. (Throughout, neglect any radiation effects.) J
(d) Use conservation of energy to calculate the speed of the alpha particle at infinity.
m/s
(e) If the two protons are released from rest and the alpha particle remains fixed, calculate the speed of the protons at infinity.
m/s

In: Physics

Bolster Foods' (BF) balance sheet shows a total of $25 million long-term debt with a coupon...

Bolster Foods' (BF) balance sheet shows a total of $25 million long-term debt with a coupon rate of 8.50%. The yield to maturity on this debt is 8.00%, and the debt has a total current market value of $27 million. The balance sheet also shows that the company has 10 million shares of stock, and the stock has a book value per share of $5.00. The current stock price is $20.00 per share, and stockholders' required rate of return, rs, is 12.25%. The company recently decided that its target capital structure should have 35% debt, with the balance being common equity. The tax rate is 25%. Calculate WACCs based on book, market, and target capital structures, and then find the sum of these three WACCs. Do not round your intermediate calculations.

a. 31.70%
b. 31.08%
c. 38.16%
d. 26.46%
e. 31.73%

In: Finance

19-28: Theoretical Probabilities. Use the theoretical method to determine the probability of the following outcomes and...

19-28: Theoretical Probabilities. Use the theoretical method to determine the probability of the following outcomes and events. State any assumptions that you make.

19. Tossing two coins and getting either no tails or one tail

20. Rolling a single die and getting an even number (2, 4, or 6)

21. Drawing a king from a standard deck of cards

22. Drawing a red card (heart or diamond) from a standard deck of cards

23. Randomly selecting a two-child family with two boys

24. Randomly selecting a three-child family with exactly two boys

25. A randomly selected person has a birthday in April.

26. A randomly selected person has a birthday in a month beginning with J.

27. Sharing a birthday with another person when you both have birthdays in December

In: Statistics and Probability

To study the effect of temperature on yield in a chemical process, five batches were produced...

To study the effect of temperature on yield in a chemical process, five batches were produced at each of three temperature levels. The results follow.

Temperature

50°C 60°C 70°C
30 26 24
20 27 29
32 30 29
35 19 31
28 23 32

a. Construct an analysis of variance table (to 2 decimals but p-value to 4 decimals, if necessary).

Source of Variation Sum of Squares Degrees of Freedom Mean Square F p-value
Treatments
Error
Total

b. Use a .05 level of significance to test whether the temperature level has an effect on the mean yield of the process.

Calculate the value of the test statistic (to 2 decimals).

The -value is - Select your answer -less than .01between .01 and .025between .025 and .05between .05 and .10greater than .10Item 12

What is your conclusion?

In: Statistics and Probability

1. Safety Dentistry stock trades at $30 per share. The company is contemplating a 3 for...

1. Safety Dentistry stock trades at $30 per share. The company is contemplating a 3 for 2 split. Assuming that the split will have no effect on the market value of its equity, what will be the company's stock price following the stock split? (express answer in dollars)

_______________

2. Marie Company is considering three independent projects, each of which requires a $4 million investment. The WAC is 11%. The estimated internal rate of return (IRR) is presented below:

Project D IRR = 14%
Project E IRR = 12%
Project F IRR = 10%

The company's optimal capital structure calls for 40% debt and 60% equity. Net income is expected to be $7,500,000. If Marie establishes its dividends from the residual model, what will be its payout ratio?

a. 18%

b. 27%

c. 45%

d. 36%

Thank you in advance for your help with these two questions...!!

In: Finance

Three point charges are arranged as follows: Charge Q1 = + 5.00 nC is located at...

Three point charges are arranged as follows: Charge Q1 = + 5.00 nC is located at the origin. Charge Q2 = -3.00 nC is located at x = +4.00 cm, y = 0 cm. Charge Q3 = + 6.00 nC is at x = 0 cm, y = -3.00 cm. a. What is the net electric field at point P with coordinates x = 4.00 cm, y = -3.00 cm?

(i) Express your answer as a vector in i, j, k notation.

(ii) Express your answer as the total magnitude and direction θ from the +x-axis. b. What is the net electric force on an proton placed at point P? Express your answer only in terms of magnitude and direction.

c. What is the acceleration of this proton? Express your answer only in terms of magnitude and direction. Mass of the proton is 1.673∙10-27 kg.

In: Physics

Question 1. During 2016, Charley wants to take advantage of the annual exclusion and make gifts...

Question 1. During 2016, Charley wants to take advantage of the annual exclusion and make gifts to his 2 married children (including their spouses) and his 5 minor grandchildren. a. How much property can Charley give away without creating a taxable gift?b. How does your answer change if Charley’s wife, Coleen, elects to join in making the gifts?

Question 2.  

In 2016, Alejandro made a gift of $2,000,000 to each of his three sons in 2016. He has made no previous gifts. What is the amount of his taxable gifts and the gift tax?

Click to access Exhibit 27-1, Unified Tax Credit, Unified Transfer Tax (2011 - 2012) and Unified Transfer Tax (2012) rates to use for this problem.

The amount of Alejandro's taxable gifts is _________ and the gift tax is $_____________

In: Accounting

Q3. PLEASE SHOW ALL WORKING If any parts of the question use values from earlier parts,...

Q3. PLEASE SHOW ALL WORKING

If any parts of the question use values from earlier parts, use the EXACT values from earlier parts.

QUESTION START An investor buys 1 share of ABC Ltd at the price of $32 on December 1, 2019. The firm is not expected to pay any dividends. Consider the following three possible scenarios for the share price on December 1, 2020: $50 with a probability of 20% $34 with a probability of 50% $27 with a probability of 15% $20 with a probability of 15%

a) Calculate the expected return for holding the share for a year.

b) Calculate the variance of return and standard deviation of return.

c) Explain the concept of diversification. Explain the benefit of diversification and how it works.

d) “The standard deviation of a portfolio's return can be reduced to zero by holding all the securities in the market.” True or false? Explain.

In: Finance

24) In a ciriminal case, the plaintiff must prove the case by the preponderance of the...

24) In a ciriminal case, the plaintiff must prove the case by the preponderance of the evidence

True

False

25) The President of the United States

a.

creates federal common law

b.

oversees administrative agencies

c.

determines the constitutionality of statutes

d.

passes statutes

27) The President of the United States

a.

creates federal common law

b.

oversees administrative agencies

c.

determines the constitutionality of statutes

d.

passes statutes

28) Punitive damages are intended to:

a.

compensate the plaintiff for medical expenses

b.

compensate the plaintiff for lost earnings

c.

pay the plaintiff for pain and suffering

d.

punish the defendant

29) The three branches of government in the United States are the:

a.

executive, legislative and administrative

b.

executive, legislative and statutory

c.

executive, legislative, and judicial

d.

executive, legislative and international

30) Promissory estoppel can be a substitute for consideration.

True

False

In: Operations Management